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Sample records for analogue site chihuahua

  1. Heterogeneous seepage at the Nopal I natural analogue site, Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Dobson, Patrick F.; Cook, Paul J.; Ghezzehei, Teamrat A.; Rodriguez, J. Alfredo; Villalba, Lourdes; de la Garza, Rodrigo

    2008-10-25

    An integrated field, laboratory, and modeling study of the Pena Blanca (Chihuahua, Mexico) natural analogue site is being conducted to evaluate processes that control the mobilization and transport of radionuclides from a uranium ore deposit. One component of this study is an evaluation of the potential for radionuclide transport through the unsaturated zone (UZ) via a seepage study in an adit at the Nopal I uranium mine, excavated 10 m below a mined level surface. Seasonal rainfall on the exposed level surface infiltrates into the fractured rhyolitic ash-flow tuff and seeps into the adit. An instrumented seepage collection system and local automated weather station permit direct correlation between local precipitation events and seepage within the Nopal I +00 adit. Monitoring of seepage within the adit between April 2005 and December 2006 indicates that seepage is highly heterogeneous with respect to time, location, and quantity. Within the back adit area, a few zones where large volumes of water have been collected are linked to fast flow path fractures (0-4 h transit times) presumably associated with focused flow. In most locations, however, there is a 1-6 month time lag between major precipitation events and seepage within the adit, with longer residence times observed for the front adit area. Seepage data obtained from this study will be used to provide input to flow and transport models being developed for the Nopal I hydrogeologic system.

  2. Heterogeneous seepage at the Nopal I natural analogue site, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Dobson, Patrick F.; Cook, Paul J.; Ghezzehei, Teamrat A.; Rodriguez, J. Alfredo; Villalba, Lourdes; de la Garza, Rodrigo

    2008-01-01

    An integrated field, laboratory, and modeling study of the Pena Blanca (Chihuahua, Mexico) natural analogue site is being conducted to evaluate processes that control the mobilization and transport of radionuclides from a uranium ore deposit. One component of this study is an evaluation of the potential for radionuclide transport through the unsaturated zone (UZ) via a seepage study in an adit at the Nopal I uranium mine, excavated 10 m below a mined level surface. Seasonal rainfall on the exposed level surface infiltrates into the fractured rhyolitic ash-flow tuff and seeps into the adit. An instrumented seepage collection system and local automated weather station permit direct correlation between local precipitation events and seepage within the Nopal I +00 adit. Monitoring of seepage within the adit between April 2005 and December 2006 indicates that seepage is highly heterogeneous with respect to time, location, and quantity. Within the back adit area, a few zones where large volumes of water have been collected are linked to fast flow path fractures (0-4 h transit times) presumably associated with focused flow. In most locations, however, there is a 1-6 month time lag between major precipitation events and seepage within the adit, with longer residence times observed for the front adit area. Seepage data obtained from this study will be used to provide input to flow and transport models being developed for the Nopal I hydrogeologic system.

  3. Heterogeneous seepage at the Nopal I natural analogue site, Chihuahua, Mexico

    Science.gov (United States)

    Dobson, Patrick F.; Ghezzehei, Teamrat A.; Cook, Paul J.; Rodríguez-Pineda, J. Alfredo; Villalba, Lourdes; de La Garza, Rodrigo

    2012-02-01

    A study of seepage occurring in an adit at the Nopal I uranium mine in Chihuahua, Mexico, was conducted as part of an integrated natural analogue study to evaluate the effects of infiltration and seepage on the mobilization and transport of radionuclides. An instrumented seepage collection system and local automated weather station permit direct correlation between local precipitation events and seepage. Field observations recorded between April 2005 and December 2006 indicate that seepage is highly heterogeneous with respect to time, location, and quantity. Seepage, precipitation, and fracture data were used to test two hypotheses: (1) that fast flow seepage is triggered by large precipitation events, and (2) that an increased abundance of fractures and/or fracture intersections leads to higher seepage volumes. A few zones in the back adit recorded elevated seepage volumes immediately following large (>20 mm/day) precipitation events, with transit times of less than 4 h through the 8-m thick rock mass. In most locations, there is a 1-6 month time lag between the onset of the rainy season and seepage, with longer times observed for the front adit. There is a less clear-cut relation between fracture abundance and seepage volume; processes such as evaporation and surface flow along the ceiling may also influence seepage.

  4. REGIONAL HYDROLOGY OF THE NOPAL I SITE, SIERRA DE PENA BLANCA, CHIHUAHUA, MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    J.A. Rodriguez-Pineda; P. Goodell; P.F. Dobson; J. Walton; R. Oliver; De La Garza; S. Harder

    2005-07-11

    The U.S. Department of Energy sponsored the drilling of three wells in 2003 near the Nopal I uranium deposit at the Sierra Pena Blanca, Chihuahua, Mexico. Piezometric information is being collected to understand groundwater flow at local and regional levels as part of an ongoing natural analogue study of radionuclide migration. Water level monitoring reported at these and other wells in the region is combined with archival data to provide a better understanding of the hydrology at Nopal I. Initial results suggest that the local hydrology is dependent on the regional hydrologic setting and that this groundwater system behaves as an unconfined aquifer. The region is dominated by an alternating sequence of highlands and basins that step down from west to east. The Sierra de Pena Blanca was downdropped from the cratonic block to the west during Cenozoic extension. The Nopal I area is near the intersection of two large listric faults, and the questa of ash flow tuffs that hosts the deposit has been subjected to complex structural events. The Pena Blanca Uranium District was originally characterized by 105 airborne radiometric anomalies, indicating widespread uranium mineralization. The Nopal I uranium deposit is located in the Sierra del Pena Blanca between the Encinillas Basin to the west, with a mean elevation of 1560 m, and the El Cuervo Basin to the east, with a mean elevation of 1230 m. The Nopal I + 10 level is at an intermediate elevation of 1463 m, with a corresponding groundwater elevation of approximately 1240 m. The regional potentiometric surface indicates flow from west to east, with the El Cuervo Basin being the discharge zone for the regional flow system. However, it appears that the local groundwater potential beneath the Nopal I site is more in accordance with the water table of the El Cuervo Basin than with that of the Encinillas Basin. This might indicate that there is limited groundwater flow between the Encinillas Basin and the Nopal I area.

  5. REGIONAL HYDROLOGY OF THE NOPAL I SITE, SIERRA DE PENA BLANCA, CHIHUAHUA, MEXICO

    International Nuclear Information System (INIS)

    Rodriguez-Pineda, J.A.; Goodell, P.; Dobson, P.F.; Walton, J.; Oliver, R.; De La Garza; Harder, S.

    2005-01-01

    The U.S. Department of Energy sponsored the drilling of three wells in 2003 near the Nopal I uranium deposit at the Sierra Pena Blanca, Chihuahua, Mexico. Piezometric information is being collected to understand groundwater flow at local and regional levels as part of an ongoing natural analogue study of radionuclide migration. Water level monitoring reported at these and other wells in the region is combined with archival data to provide a better understanding of the hydrology at Nopal I. Initial results suggest that the local hydrology is dependent on the regional hydrologic setting and that this groundwater system behaves as an unconfined aquifer. The region is dominated by an alternating sequence of highlands and basins that step down from west to east. The Sierra de Pena Blanca was downdropped from the cratonic block to the west during Cenozoic extension. The Nopal I area is near the intersection of two large listric faults, and the questa of ash flow tuffs that hosts the deposit has been subjected to complex structural events. The Pena Blanca Uranium District was originally characterized by 105 airborne radiometric anomalies, indicating widespread uranium mineralization. The Nopal I uranium deposit is located in the Sierra del Pena Blanca between the Encinillas Basin to the west, with a mean elevation of 1560 m, and the El Cuervo Basin to the east, with a mean elevation of 1230 m. The Nopal I + 10 level is at an intermediate elevation of 1463 m, with a corresponding groundwater elevation of approximately 1240 m. The regional potentiometric surface indicates flow from west to east, with the El Cuervo Basin being the discharge zone for the regional flow system. However, it appears that the local groundwater potential beneath the Nopal I site is more in accordance with the water table of the El Cuervo Basin than with that of the Encinillas Basin. This might indicate that there is limited groundwater flow between the Encinillas Basin and the Nopal I area

  6. Pena Blanca Natural Analogue Project: Summary of activities

    Energy Technology Data Exchange (ETDEWEB)

    Levy, S.; Goldstein, S.; Dobson, P.F.; Goodell, P.; Ku, T.-L.; Abdel-Fattah, A.; Saulnier, G.; Fayek, M.; de la Garza, R.

    2011-02-01

    The inactive Nopal I uranium mine in silicic tuff north of Chihuahua City, Chihuahua, Mexico, was studied as a natural analogue for an underground nuclear-waste repository in the unsaturated zone. Site stratigraphy was confirmed from new drill cores. Data from site studies include chemical and isotopic compositions of saturated- and unsaturated-zone waters. A partial geochronology of uranium enrichment and mineralization was established. Evidence pertinent to uranium-series transport in the soil zone and changing redox conditions was collected. The investigations contributed to preliminary, scoping-level performance assessment modeling.

  7. Pena blanca natural analogue project: summary of activities

    International Nuclear Information System (INIS)

    Levy, Schon S.; Goldstein, Steven J.; Abdel-Fattah, Amr I.

    2010-01-01

    The inactive Nopal I uranium mine in silicic tuff north of Chihuahua City, Chihuahua, Mexico, was studied as a natural analogue for an underground nuclear-waste repository in the unsaturated zone. Site stratigraphy was confirmed from new drill core. Datafrom site studies include chemical and isotopic compositions of saturated- and unsaturated-zone waters. A partial geochronology of uranium enrichment and mineralization was established. Evidence pertinent to uranium-series transport in the soil zone and changing redox conditions was collected. The investigations contributed to preliminary, scoping-level performance assessment modeling.

  8. Pena blanca natural analogue project: summary of activities

    Energy Technology Data Exchange (ETDEWEB)

    Levy, Schon S [Los Alamos National Laboratory; Goldstein, Steven J [Los Alamos National Laboratory; Abdel - Fattah, Amr I [Los Alamos National Laboratory

    2010-12-08

    The inactive Nopal I uranium mine in silicic tuff north of Chihuahua City, Chihuahua, Mexico, was studied as a natural analogue for an underground nuclear-waste repository in the unsaturated zone. Site stratigraphy was confirmed from new drill core. Datafrom site studies include chemical and isotopic compositions of saturated- and unsaturated-zone waters. A partial geochronology of uranium enrichment and mineralization was established. Evidence pertinent to uranium-series transport in the soil zone and changing redox conditions was collected. The investigations contributed to preliminary, scoping-level performance assessment modeling.

  9. Pena Blanca Natural Analogue Project: Summary of activities

    International Nuclear Information System (INIS)

    Levy, S.; Goldstein, S.; Dobson, P.F.; Goodell, P.; Ku, T.-L.; Abdel-Fattah, A.; Saulnier, G.; Fayek, M.; de la Garza, R.

    2011-01-01

    The inactive Nopal I uranium mine in silicic tuff north of Chihuahua City, Chihuahua, Mexico, was studied as a natural analogue for an underground nuclear-waste repository in the unsaturated zone. Site stratigraphy was confirmed from new drill cores. Data from site studies include chemical and isotopic compositions of saturated- and unsaturated-zone waters. A partial geochronology of uranium enrichment and mineralization was established. Evidence pertinent to uranium-series transport in the soil zone and changing redox conditions was collected. The investigations contributed to preliminary, scoping-level performance assessment modeling.

  10. Uranium series disequilibrium studies at the Broubster analogue site

    International Nuclear Information System (INIS)

    Longworth, G.; Ivanovich, M.; Wilkins, M.A.

    1990-11-01

    Uranium series measurements at a natural analogue site at Broubster, Caithness have been used to investigate radionuclide migration over periods ranging from several hundred to 10 6 years. The measured values for the uranium concentration and activity values 234 U/ 238 U and 230 Th/ 234 U indicate that the geochemical system is more complicated than that originally proposed of uranium dispersion and water transport into a peat bog. There appears to be little thorium mobility although there is evidence for an appreciable fraction of thorium on the colloidal phase. (author)

  11. Uranium series disequilibrium studies at the Broubster analogue site

    International Nuclear Information System (INIS)

    Longworth, G.; Ivanovich, M.; Wilkins, M.A.

    1989-09-01

    Uranium series measurements at a natural analogue site at Broubster, Caithness have been used to investigate radionuclide migration over a period of several hundred to 10 6 years. The measured values for the uranium concentration and activity ratios 234 U/ 238 U and 230 Th/ 234 U indicate that the geochemical system is more complicated than that originally proposed of uranium dispersion and water transport into a peat bog. There appears to be little thorium mobility although there is evidence for an appreciable fraction of thorium on the colloidal phases. (author)

  12. Mutnovsky and Gorely Volcanoes, Kamchatka as Planetary Analogue Sites

    Science.gov (United States)

    Evdokimova, N.; Izbekov, P. E.; Krupskaya, V.; Muratov, A.

    2016-12-01

    Recent advances in Mars studies suggest that volcanic rocks, which dominated Martian surface in the past, have been exposed to alteration processes in a water-bearing environment during Noachian, before 3.7 Gy. Active volcanoes on Earth are natural laboratories, where volcanic processes and their associated products can be studied directly. This is particularly important for studying of alteration of juvenile volcanic products in aqueous environment because of the transient nature of some of the alteration products, as well as the environment itself. Terrestrial analogues help us to better understand processes on Mars; they are particularly useful as a test sites for preparation to future Mars missions. In this presentation we describe planetary analogue sites at Mutnovsky and Gorely Volcanoes in Kamchatka, which might be helpful for comparative studies and preparation to future Mars missions. Mutnovsky and Gorely Volcanoes are located 75 km south of Petropavlovsk-Kamchatsky, in the southern part of the Kamchatka Peninsula, Russia. The modern volcanic landscape in the area was shaped in Holocene (recent 10,000 years) through intermittent eruption of magmas ranging in composition from basalts to dacites and rhyodacites, with basaltic andesite lavas dominating in the modern relief. Two localities could be of a particular interest: (1) Mutnovsky NW thermal field featuring processes of active hydrothermal alteration of lavas of basaltic andesite and (2) dry lake at the bottom of Gorely caldera featuring products of mechanical disintegration of basaltic andesite lavas by eolian processes with short seasonal sedimentation in aqueous environment.

  13. Martian analogue test site - pilbara craton, western Australia

    Science.gov (United States)

    Brown, A.; Allwood, A.; Walter, M. R.; van Kranendonk, M.

    All exploration for life elsewhere depends on extrapolation from our knowledge of Earth. If the target is former microbial life, for example on Mars, there is no better analogue on Earth than the 3.5 billion year old rocks of the Pilbara region, Western Australia. This area is home to signs of the earliest life on Earth in the form of microbe, many famous stromatolitic horizons and carbon isotope biosignatures. These occur in a volcanic terrain, with weathering and hydrothermal alteration, which also has some similarity to Mars. The geology of this region is known in detail after decades of mapping and other studies. Current work includes studies to resolve disputes about the biogenicity of the microfossils and stromatolites. On balance, biological origins are most likely. In any event, problems of demonstrating biogenicity on other planets will be far more severe, and the work on the Pilbara materials will illuminate those problems. Also underway is mineral mapping of the volcanic, hydrothermal and fossiliferous units using both airborne and hand-held short-wave infrared spectrometers, We are able to map the fossiliferous units using this technique and contend that it would be a powerful exploration technique on Mars and elsewhere. Using the Pilbara as an analogue for other bodies in the Solar System can extend to using it as a place to test instrument packages under realistic conditions. The region has good air and road access, and good supporting infrastructure.

  14. A case of factor X deficiency in a Chihuahua dog.

    Science.gov (United States)

    Heuss, Jessica; Weatherton, Linda

    2016-08-01

    A juvenile Chihuahua dog developed hemoperitoneum after routine ovariohysterectomy. She was managed with packed red blood cell and fresh frozen plasma transfusions as well as an exploratory laparotomy to verify ligature sites. No recurrence of hemorrhage occurred. Factor X deficiency was diagnosed and confirmed with repeat analysis including during times of health.

  15. Chemical speciation modelling of the South Terras and Madeira Abyssal Plain natural analogue sites

    International Nuclear Information System (INIS)

    Duffield, J.R.; Xu Langqui; Williams, D.R.

    1988-11-01

    The chemical speciation of uranium has been modelled using field data from the South Terras and Madeira Abyssal Plain natural analogue sites. In general, validation is good, particularly for the Abyssal Plain model. Problems regarding uranium redox couples have been highlighted as have other areas requiring further consideration for building into the thermodynamic models. (author)

  16. The uranium source-term mineralogy and geochemistry at the Broubster natural analogue site, Caithness

    International Nuclear Information System (INIS)

    Milodowski, A.E.; Pearce, J.M.; Basham, I.R.; Hyslop, E.K.

    1991-01-01

    The British Geological Survey (BGS) has been conducting a coordinated research programme at the Broubster natural analogue site in Caithness, north Scotland. This work on a natural radioactive geochemical system has been carried out with the aim of improving our confidence in using predictive models of radionuclide migration in the geosphere. This report is one of a series being produced and it concentrates on the mineralogical characterization of the uranium distribution in the limestone unit considered as the 'source-term' in the natural analogue model

  17. Guarijio de Arechuyvo, Chihuahua (Guarijio of Arechuyvo, Chihuahua).

    Science.gov (United States)

    Miller, Wick R.

    This document is one of 17 volumes on indigenous Mexican languages and is the result of a project undertaken by the Archivo de Lenguas Indigenas de Mexico. This volume contains information on Guarijio, an indigenous language of Mexico spoken in Arechuyvo, Chihuahua. The objective of collecting such a representative sampling of the linguistic…

  18. Federalization of Education in Chihuahua

    Science.gov (United States)

    Marak, Andrae M.

    2005-01-01

    This article examines the politics behind the initial centralization of primary education in Chihuahua, Mexico during the 1920s and 1930s. The article argues that the centralization of primary education was one of many tools used by the federal government to consolidate its power in the wake of the Mexican Revolution (1910-1917) and create a…

  19. Natural analogues of radionuclide migration: reconnaissance study of sites (May 1985-March 1986)

    International Nuclear Information System (INIS)

    Hooker, P.J.; Ball, T.K.; Basham, I.R.; Bloodworth, A.J.; Roberts, P.D.; Ivanovich, M.

    1986-01-01

    Research into natural analogues of radionuclide migration provide data for supporting computer codes that describe the processes of transport and retardation. Such models are appropriate to the far-fields of shallow and deep radioactive waste repositories. The objective of this research project was to define locations within the UK and abroad worthy of detailed investigation. Site investigations and evaluations were carried out at a number of UK localities. The main focus of this survey has been on uraniferous veins in places at near surface where transport of uranium into sediments has occurred. Several uranium rich mineralisations associated with granite margins were visited in Cornwall, Devon and along the Solway Firth coast in Scotland; the disused U mine at South Terras in Cornwall and the coastal site at Needle's Eye near Dalbeattie are confirmed as future study sites. Results to hand from the sediments of Loch Lomand warrant further measurements of iodine and bromine in fresh cores. (author)

  20. Natural decay series radionuclide studies at the Needle's Eye Natural Analogue Site, II, 1989-1991

    International Nuclear Information System (INIS)

    MacKenzie, A.B.; Whitton, A.M.; Shimmield, T.M.; Jemielita, R.A.; Scott, R.D.; Hooker, P.J.

    1991-12-01

    HMIP has a research programme investigating some naturally radioactive sites as geochemical analogues of radionuclide migration. The objective is to test thermodynamic databases and computer codes used for modelling radionuclide migration under environmental conditions. This report describes the study of transport and retardation processes affecting natural radionuclides, mainly uranium (U), in the vicinity of pitchblende veins in the cliff at Needle's Eye on the Solway Coast, SW Scotland. The natural decay series results from this study have been used to develop a well constrained geochemical model within which the codes can be tested. A conceptual geochemical model for the behaviour of U at the site was developed in stage I of the study; work in stage II is concerned with improving the information available on the U source term, groundwater chemistry, U aqueous phase specification, U retardation by fracture-lining minerals during fissure flow of groundwater, U-organic associations and loss of U from the site by stream drainage. (author)

  1. Uranium mineral - groundwater equilibrium at the Palmottu natural analogue study site, Finland

    International Nuclear Information System (INIS)

    Ahonen, L.; Ruskeeniemi, T.; Blomqvist, R.; Ervanne, H.; Jaakkola, T.

    1993-01-01

    The redox-potential, pH, chemical composition of fracture waters, and uraninite alteration associated with the Palmottu uranium mineralization (a natural analogue study site for radioactive waste disposal in southwestern Finland), have been studied. The data have been interpreted by means of thermodynamic calculations. The results indicate equilibrium between uraninite, ferric hydroxide and groundwater in the bedrock of the study site. Partially oxidized uraninite (UO 2 .33) and ferric hydroxide are in equilibrium with fresh, slightly acidic and oxidized water type, while primary uraninite is stable with deeper waters that have a higher pH and lower Eh. Measured Eh-pH values of groundwater cluster within a relatively narrow range indicating buffering by heterogenous redox-processes. A good consistency between measured Eh and analyzed uranium oxidation states was observed

  2. The geological, geochemical, topographical and hydrogeological characteristics of the Broubster natural analogue site, Caithness

    International Nuclear Information System (INIS)

    Ball, T.K.; Milodowski, A.E.

    1991-01-01

    One of the four analogue sites chosen for investigation by the British Geological Survey is the uranium mineralization at Broubster, Caithness, Scotland. Naturally occurring uranium has been leached from a thin mineralized limestone horizon and has been carried by groundwater flow into a peat bog about 100 m away. This process has probably been going on for at least 5 000 years. Standard surveying, hydrogeological and geochemical methods have been applied in the investigation and analysis of the area. Selected samples of the mineralization, peat soils and associated groundwaters have been examined in detail. This report summarizes the main findings accumulated since 1968 when the site was first discovered, and provides a useful information base for further modelling work. 27 refs.; 12 plates; 40 figs.; 17 tabs

  3. The geological, geochemical, topographical and hydrogeological characteristics of the Broubster natural analogue site, Caithness

    International Nuclear Information System (INIS)

    Ball, T.K.; Milodowski, A.E.

    1989-06-01

    One of the four natural analogue sites chosen for investigation by the British Geological Survey is the uranium mineralisation at Broubster, Caithness, Scotland. Naturally occurring uranium has been leached from a thin mineralised limestone horizon and has been carried by groundwater flow into a peat bog about 100m away. This process has probably been going on for at least 5000 years. Standard surveying, hydrogeological and geochemical methods have been applied in the investigation and analysis of the area. Selected samples of the mineralisation, peat soils and associated groundwaters have been examined in detail. This report summarises the main findings accumulated since 1968 when the site was first discovered, and provides a useful information base for further modelling work. (author)

  4. Gallbladder agenesis in a Chihuahua.

    Science.gov (United States)

    Kamishina, Hiroaki; Katayama, Masaaki; Okamura, Yasuhiko; Sasaki, Jun; Chiba, Satoshi; Goryo, Masanobu; Sato, Reeko; Yasuda, Jun

    2010-07-01

    A 4-year-old neutered male Chihuahua was presented with a history of anorexia and vomiting. Continuous elevation of liver enzymes was found on repeated blood examinations and the dog was referred to us for further evaluation. The absence of gallbladder was suspected on ultrasonography. Exploratory laparotomy and retrograde cholangiography confirmed gallbladder agenesis and a possible hypoplasia of the right medial and lateral liver lobes. Histologically, proliferation of bile ductules associated with portal fibrosis and pseudolobular formation were apparent in the liver lobes.

  5. Syringomyelia and Craniocervical Junction Abnormalities in Chihuahuas

    OpenAIRE

    Kiviranta, A.‐M.; Rusbridge, C.; Laitinen‐Vapaavuori, O.; Hielm‐Björkman, A.; Lappalainen, A.K.; Knowler, S.P.; Jokinen, T.S.

    2017-01-01

    Background: Chiari-like malformation (CM) and syringomyelia (SM) are widely reported in Cavalier King Charles Spaniels and Griffon Bruxellois dogs. Increasing evidence indicates that CM and SM also occur in other small and toy breed dogs, such as Chihuahuas. Objectives: To describe the presence of SM and craniocervical junction (CCJ) abnormalities in Chihuahuas and to evaluate the possible association of CCJ abnormalities with SM. To describe CM/SM-related clinical signs and neuro...

  6. FIGIFIGO as a tool to characterize and identify planetary analogue sites

    Science.gov (United States)

    Gritsevich, M.; Peltoniemi, J.; Hakala, T.; Muinonen, K.

    2014-07-01

    We present an overview of the Finnish Geodetic Institute's field goniospectrometer (FIGIFIGO) and highlight its usability to study extraterrestrial analogues on the Earth. The design concept of this custom-made instrument has been proved to have a number of advantages, such as a well-adopted user-friendly interface, a high level of automation, and excellent suitability for field measurements within a wide range of weather conditions. It is perfect for collection of reference data on a given target in natural undisturbed (and well-recorded for further data interpretation) conditions. The instrument communicates via a controlled computer with an implemented simple and user-friendly interface. This allows users to easily set up optional parameters at the beginning of the measurement series. Thus a number of details may be modified, such as the initial position of the sensor, the range and speed of further automated zenith turns, and length of the turnable arm holding the selected optics (including an option for a computer-turned linear polarizer) above the target. The assembly and operation of the instrument are fast and efficient in both laboratory and field conditions. It is battery powered and easily portable, including possible transportation by plane, car, boat, or sledge. The system includes a sky camera to detect the goniometer orientation and a pyranometer to monitor the actual illumination conditions. A fine-tune mirror is used for spatial correction of the optics footprint. Recent calibration of the system has significantly increased the measurement robustness and data reliability, and has provided the operators with information on how to operate the instrument in the most efficient and accurate way. Measurement campaigns are organized frequently and significant amount of reference data has been already collected. The identification of new planetary analogue sites and characterization of known ones using FIGIFIGO could offer new possibilities and provide

  7. THE PENA BLANCA NATURAL ANALOGUE PERFORMANCE ASSESSMENT MODEL

    Energy Technology Data Exchange (ETDEWEB)

    G. Saulnier and W. Statham

    2006-04-16

    The Nopal I uranium mine in the Sierra Pena Blanca, Chihuahua, Mexico serves as a natural analogue to the Yucca Mountain repository. The Pena Blanca Natural Analogue Performance Assessment Model simulates the mobilization and transport of radionuclides that are released from the mine and transported to the saturated zone. The Pena Blanca Natural Analogue Performance Assessment Model uses probabilistic simulations of hydrogeologic processes that are analogous to the processes that occur at the Yucca Mountain site. The Nopal I uranium deposit lies in fractured, welded, and altered rhyolitic ash-flow tuffs that overlie carbonate rocks, a setting analogous to the geologic formations at the Yucca Mountain site. The Nopal I mine site has the following analogous characteristics as compared to the Yucca Mountain repository site: (1) Analogous source--UO{sub 2} uranium ore deposit = spent nuclear fuel in the repository; (2) Analogous geology--(i.e. fractured, welded, and altered rhyolitic ash-flow tuffs); (3) Analogous climate--Semiarid to arid; (4) Analogous setting--Volcanic tuffs overlie carbonate rocks; and (5) Analogous geochemistry--Oxidizing conditions Analogous hydrogeology: The ore deposit lies in the unsaturated zone above the water table.

  8. THE PENA BLANCA NATURAL ANALOGUE PERFORMANCE ASSESSMENT MODEL

    International Nuclear Information System (INIS)

    G. Saulnier; W. Statham

    2006-01-01

    The Nopal I uranium mine in the Sierra Pena Blanca, Chihuahua, Mexico serves as a natural analogue to the Yucca Mountain repository. The Pena Blanca Natural Analogue Performance Assessment Model simulates the mobilization and transport of radionuclides that are released from the mine and transported to the saturated zone. The Pena Blanca Natural Analogue Performance Assessment Model uses probabilistic simulations of hydrogeologic processes that are analogous to the processes that occur at the Yucca Mountain site. The Nopal I uranium deposit lies in fractured, welded, and altered rhyolitic ash-flow tuffs that overlie carbonate rocks, a setting analogous to the geologic formations at the Yucca Mountain site. The Nopal I mine site has the following analogous characteristics as compared to the Yucca Mountain repository site: (1) Analogous source--UO 2 uranium ore deposit = spent nuclear fuel in the repository; (2) Analogous geology--(i.e. fractured, welded, and altered rhyolitic ash-flow tuffs); (3) Analogous climate--Semiarid to arid; (4) Analogous setting--Volcanic tuffs overlie carbonate rocks; and (5) Analogous geochemistry--Oxidizing conditions Analogous hydrogeology: The ore deposit lies in the unsaturated zone above the water table

  9. Final report of the Peña Blanca natural analogue project

    Energy Technology Data Exchange (ETDEWEB)

    Levy, Schön S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Goldstein, Steven Joel [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Abdel-Fattah, Amr I. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Amato, Ronald S. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Anthony, Elizabeth [Univ. of Texas, El Paso, TX (United States); Cook, Paul [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Dobson, Patrick F. [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Fayek, Mostafa [Univ. of Manitoba, Winnipeg (Canada); French, Diana [Univ. of Texas, El Paso, TX (United States); Garza, Rodrigo de [Univ. Autonoma de Chihuahua (Mexico); Ghezzehei, Teamrat [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Goodell, Philip C. [Univ. of Texas, El Paso, TX (United States); Harder, Steven H. [Univ. of Texas, El Paso, TX (United States); Ku, Teh-Lung [Univ. of Southern California, Los Angeles, CA (United States); Luo, Shangde [Univ. of Southern California, Los Angeles, CA (United States); Murrell, Michael Tildon [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Norman, Deborah E. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Nunn, Andrew J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Oliver, Ronald [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Pekar-Carpenter, Katrina [Univ. of Texas, El Paso, TX (United States); Rearick, Michael Sean [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ren, Minghua [Univ. of Texas, El Paso, TX (United States); Reyes-Cortes, Ignacio [Univ. Autonoma de Chihuahua (Mexico); Pineda, Jose Alfredo [El Instituto de Ecologia (INECOL) (Mexico); Saulnier, George [AREVA Federal Services LLC, Charlotte, NC (United States); Tarimala, Sowmitri [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Walton, John [Univ. of Texas, El Paso, TX (United States)

    2016-10-04

    The Peña Blanca region, 50 km north of Chihuahua City, Chihuahua, México, was a target of uranium exploration and mining by the Mexican government. After mining ceased in 1981, researchers became interested in this region as a study area for subsurface uranium migration with relevance to geologic disposal of nuclear waste. Many studies related to this concept were conducted at the Nopal I mine site located on a cuesta (hill) of the Sierra Peña Blanca. This site has geologic, tectonic, hydrologic, and geochemical similarities to Yucca Mountain, Nevada, a formerly proposed site for a high-level nuclear-waste repository in the unsaturated zone. The U.S. Department of Energy (U.S. DOE), Office of Civilian Radioactive Waste Management (OCRWM), sponsored studies at Nopal I in the 1990s and supported the drilling of three research wells – PB1, PB2, and PB3 – at the site in 2003. Beginning in 2004, the Peña Blanca Natural Analogue Project was undertaken by U.S. DOE, OCRWM to develop a three-dimensional conceptual model of the transport of uranium and its radiogenic daughter products at the Nopal I site.

  10. Simulation and preparation of surface EVA in reduced gravity at the Marseilles Bay subsea analogue sites

    Science.gov (United States)

    Weiss, P.; Gardette, B.; Chirié, B.; Collina-Girard, J.; Delauze, H. G.

    2012-12-01

    submarines). COMEX is currently preparing a space mission simulation in the Marseilles Bay (foreseen in June 2012), and the paper will give an overview of the different underwater analogue sites that are available to the scientific community for the simulation of surface EVA or the test of scientific instruments and devices.

  11. A mini-library of TBA analogues containing 3'-3' and 5'-5' inversion of polarity sites.

    Science.gov (United States)

    Esposito, V; Galeone, A; Mayol, L; Randazzo, A; Virgilio, A; Virno, A

    2007-01-01

    Several researches have been devoted to structure-activity relationship and to post-SELEX modifications of the thrombin binding aptamer (TBA), one of the first aptamers discovered by the SELEX methodology. However, no studies on TBA dealing with the effects of introduction of inversion of polarity sites have been reported yet. In this frame, we have undertaken the synthesis and the study of a mini-library composed of several TBA analogues containing a 3'-3' or a 5'-5' inversion of polarity site at different positions into the sequence. Particularly, in this article, we present preliminary results about their structural and biological properties.

  12. Syringomyelia and Craniocervical Junction Abnormalities in Chihuahuas.

    Science.gov (United States)

    Kiviranta, A-M; Rusbridge, C; Laitinen-Vapaavuori, O; Hielm-Björkman, A; Lappalainen, A K; Knowler, S P; Jokinen, T S

    2017-11-01

    Chiari-like malformation (CM) and syringomyelia (SM) are widely reported in Cavalier King Charles Spaniels and Griffon Bruxellois dogs. Increasing evidence indicates that CM and SM also occur in other small and toy breed dogs, such as Chihuahuas. To describe the presence of SM and craniocervical junction (CCJ) abnormalities in Chihuahuas and to evaluate the possible association of CCJ abnormalities with SM. To describe CM/SM-related clinical signs and neurologic deficits and to investigate the association of CM/SM-related clinical signs with signalment, SM, or CCJ abnormalities. Fifty-three client-owned Chihuahuas. Prospective study. Questionnaire analyses and physical and neurologic examinations were obtained before magnetic resonance and computed tomography imaging. Images were evaluated for the presence of SM, CM, and atlantooccipital overlapping. Additionally, medullary kinking, dorsal spinal cord compression, and their sum indices were calculated. Scratching was the most common CM/SM-related clinical sign and decreased postural reaction the most common neurologic deficit in 73 and 87% of dogs, respectively. Chiari-like malformation and SM were present in 100 and 38% of dogs, respectively. Syringomyelia was associated with the presence of CM/SM-related clinical signs (P = 0.034), and medullary kinking and sum indices were higher in dogs with clinical signs (P = 0.016 and P = 0.007, respectively). Syringomyelia and CCJ abnormalities are prevalent in Chihuahuas. Syringomyelia was an important factor for the presence of CM/SM-related clinical signs, but many dogs suffered from similar clinical signs without being affected by SM, highlighting the clinical importance of CCJ abnormalities in Chihuahuas. Copyright © 2017 The Authors. Journal of Veterinary Internal Medicine published by Wiley Periodicals, Inc. on behalf of the American College of Veterinary Internal Medicine.

  13. Geologic studies in the Sierra de Pena Blanca, Chihuahua, Mexico

    Science.gov (United States)

    Reyes-Cortes, Ignacio Alfonso

    The Sierra del Cuervo has been endowed with uranium mineralization, which has attracted many geological studies, and recently the author was part of a team with the goal of selecting a site of a radioactive waste repository. The first part of the work adds to the regional framework of stratigraphy and tectonics of the area. It includes the idea of a pull apart basin development, which justifies the local great thickness of the Cuervo Formation. It includes the regional structural frame work and the composite stratigraphic column of the Chihuahua Trough and the equivalent Cretaceous Mexican Sea. The general geologic features of the NE part of the Sierra del Cuervo are described, which include the folded ignimbrites and limestones in that area; the irregular large thicknesses of the Cuervo Formation; and the western vergence of the main folding within the area. Sanidine phenocrystals gave ages of 54.2 Ma and 51.8 Ma ± 2.3 Ma. This is the first time these dates have been reported in print. This age indicates a time before the folded structures which outcrop in the area, and 44 Ma is a date after the Cuervo Formation was folded. The Hidalgoan orogeny cycle affected the rocks between this lapse of time. Since then the area has been partially affected by three tensional overlapped stages, which resulted in the actual Basin and Range physiography. The jarosite related to the tectonic activity mineralization has been dated by the Ar-Ar method and yields an age of 9.8 Ma. This is the first report of a date of mineralization timing at Pena Blanca Uranium District in the Sierra del Cuervo. These are some of the frame work features that justify the allocation of a radioactive waste repository in the Sierra del Cuervo. An alluvial fan system within the Boquilla Colorada microbasin was selected as the best target for more detailed site assessment. The study also included the measurement of the alluvium thicknesses by geoelectric soundings; studies of petrography and weathered

  14. Photoaffinity labeling with cholesterol analogues precisely maps a cholesterol-binding site in voltage-dependent anion channel-1.

    Science.gov (United States)

    Budelier, Melissa M; Cheng, Wayland W L; Bergdoll, Lucie; Chen, Zi-Wei; Janetka, James W; Abramson, Jeff; Krishnan, Kathiresan; Mydock-McGrane, Laurel; Covey, Douglas F; Whitelegge, Julian P; Evers, Alex S

    2017-06-02

    Voltage-dependent anion channel-1 (VDAC1) is a highly regulated β-barrel membrane protein that mediates transport of ions and metabolites between the mitochondria and cytosol of the cell. VDAC1 co-purifies with cholesterol and is functionally regulated by cholesterol, among other endogenous lipids. Molecular modeling studies based on NMR observations have suggested five cholesterol-binding sites in VDAC1, but direct experimental evidence for these sites is lacking. Here, to determine the sites of cholesterol binding, we photolabeled purified mouse VDAC1 (mVDAC1) with photoactivatable cholesterol analogues and analyzed the photolabeled sites with both top-down mass spectrometry (MS), and bottom-up MS paired with a clickable, stable isotope-labeled tag, FLI -tag. Using cholesterol analogues with a diazirine in either the 7 position of the steroid ring (LKM38) or the aliphatic tail (KK174), we mapped a binding pocket in mVDAC1 localized to Thr 83 and Glu 73 , respectively. When Glu 73 was mutated to a glutamine, KK174 no longer photolabeled this residue, but instead labeled the nearby Tyr 62 within this same binding pocket. The combination of analytical strategies employed in this work permits detailed molecular mapping of a cholesterol-binding site in a protein, including an orientation of the sterol within the site. Our work raises the interesting possibility that cholesterol-mediated regulation of VDAC1 may be facilitated through a specific binding site at the functionally important Glu 73 residue. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  15. Isolation of nucleotide binding site-leucine rich repeat and kinase resistance gene analogues from sugarcane (Saccharum spp.).

    Science.gov (United States)

    Glynn, Neil C; Comstock, Jack C; Sood, Sushma G; Dang, Phat M; Chaparro, Jose X

    2008-01-01

    Resistance gene analogues (RGAs) have been isolated from many crops and offer potential in breeding for disease resistance through marker-assisted selection, either as closely linked or as perfect markers. Many R-gene sequences contain kinase domains, and indeed kinase genes have been reported as being proximal to R-genes, making kinase analogues an additionally promising target. The first step towards utilizing RGAs as markers for disease resistance is isolation and characterization of the sequences. Sugarcane clone US01-1158 was identified as resistant to yellow leaf caused by the sugarcane yellow leaf virus (SCYLV) and moderately resistant to rust caused by Puccinia melanocephala Sydow & Sydow. Degenerate primers that had previously proved useful for isolating RGAs and kinase analogues in wheat and soybean were used to amplify DNA from sugarcane (Saccharum spp.) clone US-01-1158. Sequences generated from 1512 positive clones were assembled into 134 contigs of between two and 105 sequences. Comparison of the contig consensuses with the NCBI sequence database using BLASTx showed that 20 had sequence homology to nuclear binding site and leucine rich repeat (NBS-LRR) RGAs, and eight to kinase genes. Alignment of the deduced amino acid sequences with similar sequences from the NCBI database allowed the identification of several conserved domains. The alignment and resulting phenetic tree showed that many of the sequences had greater similarity to sequences from other species than to one another. The use of degenerate primers is a useful method for isolating novel sugarcane RGA and kinase gene analogues. Further studies are needed to evaluate the role of these genes in disease resistance.

  16. Scientific results and lessons learned from an integrated crewed Mars exploration simulation at the Rio Tinto Mars analogue site

    Science.gov (United States)

    Orgel, Csilla; Kereszturi, Ákos; Váczi, Tamás; Groemer, Gernot; Sattler, Birgit

    2014-02-01

    Between 15 and 25 April 2011 in the framework of the PolAres programme of the Austrian Space Forum, a five-day field test of the Aouda.X spacesuit simulator was conducted at the Rio Tinto Mars-analogue site in southern Spain. The field crew was supported by a full-scale Mission Control Center (MCC) in Innsbruck, Austria. The field telemetry data were relayed to the MCC, enabling a Remote Science Support (RSS) team to study field data in near-real-time and adjust the flight planning in a flexible manner. We report on the experiences in the field of robotics, geophysics (Ground Penetrating Radar) and geology as well as life sciences in a simulated spaceflight operational environment. Extravehicular Activity (EVA) maps had been prepared using Google Earth and aerial images. The Rio Tinto mining area offers an excellent location for Mars analogue simulations. It is recognised as a terrestrial Mars analogue site because of the presence of jarosite and related sulphates, which have been identified by the NASA Mars Exploration Rover "Opportunity" in the El Capitan region of Meridiani Planum on Mars. The acidic, high ferric-sulphate content water of Rio Tinto is also considered as a possible analogue in astrobiology regarding the analysis of ferric sulphate related biochemical pathways and produced biomarkers. During our Mars simulation, 18 different types of soil and rock samples were collected by the spacesuit tester. The Raman results confirm the presence of minerals expected, such as jarosite, different Fe oxides and oxi-hydroxides, pyrite and complex Mg and Ca sulphates. Eight science experiments were conducted in the field. In this contribution first we list the important findings during the management and realisation of tests, and also a first summary of the scientific results. Based on these experiences suggestions for future analogue work are also summarised. We finish with recommendations for future field missions, including the preparation of the experiments

  17. A natural analogue for high-level waste in tuff: Chemical analysis and modeling of the Valles site

    International Nuclear Information System (INIS)

    Stockman, H.W.; Krumhansl, J.L.; Ho, C.K.; Kovach, L.; McConnell, V.S.

    1995-01-01

    The contact between an obsidian flow and a steep-walled tuff canyon was examined as an analogue for a high-level waste repository. The analogue site is located in the Valles Caldera in New Mexico, where a massive obsidian flow filled a paleocanyon in the Battleship Rock Tuff. The obsidian flow provided a heat source, analogous to waste panels or an igneous intrusion in a repository, and caused evaporation and migration of water. The tuff and obsidian samples were analyzed for major and trace elements and mineralogy by INAA, XRF, x-ray diffraction, and scanning electron microscopy and electron microprobe. Samples were also analyzed for D/H and 39 Ar/ 40 Ar isotopic composition. Overall, the effects of the heating event seem to have been slight and limited to the tuff nearest the contact. There is some evidence of devitrification and migration of volatiles in the tuff within 10 m of the contact, but variations in major and trace element chemistry are small and difficult to distinguish from the natural (pre-heating) variability of the rocks

  18. THE PENA BLANCA NATURAL ANALOGUE PERFORMANCE ASSESSMENT MODEL

    Energy Technology Data Exchange (ETDEWEB)

    G.J. Saulnier Jr; W. Statham

    2006-03-10

    The Nopal I uranium mine in the Sierra Pena Blanca, Chihuahua, Mexico serves as a natural analogue to the Yucca Mountain repository. The Pena Blanca Natural Analogue Performance Assessment Model simulates the mobilization and transport of radionuclides that are released from the mine and transported to the saturated zone. the Pena Blanca Natural Analogue Model uses probabilistic simulations of hydrogeologic processes that are analogous to the processes that occur at the Yucca Mountain site. The Nopal I uranium deposit lies in fractured, welded, and altered rhyolitic ash flow tuffs that overlie carbonate rocks, a setting analogous to the geologic formations at the Yucca Mountain site. The Nopal I mine site has the following characteristics as compared to the Yucca Mountain repository site. (1) Analogous source: UO{sub 2} uranium ore deposit = spent nuclear fuel in the repository; (2) Analogous geologic setting: fractured, welded, and altered rhyolitic ash flow tuffs overlying carbonate rocks; (3) Analogous climate: Semiarid to arid; (4) Analogous geochemistry: Oxidizing conditions; and (5) Analogous hydrogeology: The ore deposit lies in the unsaturated zone above the water table. The Nopal I deposit is approximately 8 {+-} 0.5 million years old and has been exposed to oxidizing conditions during the last 3.2 to 3.4 million years. The Pena Blanca Natural Analogue Model considers that the uranium oxide and uranium silicates in the ore deposit were originally analogous to uranium-oxide spent nuclear fuel. The Pena Blanca site has been characterized using field and laboratory investigations of its fault and fracture distribution, mineralogy, fracture fillings, seepage into the mine adits, regional hydrology, and mineralization that shows the extent of radionuclide migration. Three boreholes were drilled at the Nopal I mine site in 2003 and these boreholes have provided samples for lithologic characterization, water-level measurements, and water samples for laboratory

  19. THE PENA BLANCA NATURAL ANALOGUE PERFORMANCE ASSESSMENT MODEL

    International Nuclear Information System (INIS)

    G.J. Saulnier Jr; W. Statham

    2006-01-01

    The Nopal I uranium mine in the Sierra Pena Blanca, Chihuahua, Mexico serves as a natural analogue to the Yucca Mountain repository. The Pena Blanca Natural Analogue Performance Assessment Model simulates the mobilization and transport of radionuclides that are released from the mine and transported to the saturated zone. the Pena Blanca Natural Analogue Model uses probabilistic simulations of hydrogeologic processes that are analogous to the processes that occur at the Yucca Mountain site. The Nopal I uranium deposit lies in fractured, welded, and altered rhyolitic ash flow tuffs that overlie carbonate rocks, a setting analogous to the geologic formations at the Yucca Mountain site. The Nopal I mine site has the following characteristics as compared to the Yucca Mountain repository site. (1) Analogous source: UO 2 uranium ore deposit = spent nuclear fuel in the repository; (2) Analogous geologic setting: fractured, welded, and altered rhyolitic ash flow tuffs overlying carbonate rocks; (3) Analogous climate: Semiarid to arid; (4) Analogous geochemistry: Oxidizing conditions; and (5) Analogous hydrogeology: The ore deposit lies in the unsaturated zone above the water table. The Nopal I deposit is approximately 8 ± 0.5 million years old and has been exposed to oxidizing conditions during the last 3.2 to 3.4 million years. The Pena Blanca Natural Analogue Model considers that the uranium oxide and uranium silicates in the ore deposit were originally analogous to uranium-oxide spent nuclear fuel. The Pena Blanca site has been characterized using field and laboratory investigations of its fault and fracture distribution, mineralogy, fracture fillings, seepage into the mine adits, regional hydrology, and mineralization that shows the extent of radionuclide migration. Three boreholes were drilled at the Nopal I mine site in 2003 and these boreholes have provided samples for lithologic characterization, water-level measurements, and water samples for laboratory analysis

  20. Committed dose assessment based on background outdoor gamma exposure in Chihuahua City, Mexico

    International Nuclear Information System (INIS)

    Luevano G, S.; Perez T, A.; Pinedo A, C.; Renteria V, M.; Carrillo F, J.; Montero C, M. E.

    2015-10-01

    Full text: Determining ionizing radiation in a geographic area serves to assess its effects on populations health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the committed dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, annual effective dose, and the lifetime cancer risk, 48 sampling points were randomly selected along the Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Muller counter. At the same sites, 48 soil samples were taken to obtain the activity concentrations of 226 Ra, 232 Th, 40 K and their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Outdoor gamma dose rates ranged from 56 to 193 n Gy h -1 . Results indicated that lifetime effective dose to inhabitants of Chihuahua City is in average of 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of activity concentrations in soil were 51.8, 73.1, and 1096.5 Bq kg -1 , of 226 Ra, 232 Th and 40 K, respectively. From the analysis of the spatial distribution of 232 Th, 226 Ra, and 40 K is to north, to north-center, and to south of city, respectively. In conclusion, natural background gamma dose received by inhabitants of Chihuahua City is high and mainly due to geological characteristics of the zone. (Author)

  1. Committed dose assessment based on background outdoor gamma exposure in Chihuahua City, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Luevano G, S.; Perez T, A.; Pinedo A, C.; Renteria V, M. [Universidad Autonoma de Chihuahua, Facultad de Zootecnia y Ecologia, Perif. Francisco R. Almada Km 1, 31415 Chihuahua, Chih. (Mexico); Carrillo F, J.; Montero C, M. E., E-mail: mrenteria@uach.mx [Centro de Investigacion en Materiales Avanzados, Miguel de Cervantes 120, 31136 Chihuahua, Chih. (Mexico)

    2015-10-15

    Full text: Determining ionizing radiation in a geographic area serves to assess its effects on populations health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the committed dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, annual effective dose, and the lifetime cancer risk, 48 sampling points were randomly selected along the Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Muller counter. At the same sites, 48 soil samples were taken to obtain the activity concentrations of {sup 226}Ra, {sup 232}Th, {sup 40}K and their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Outdoor gamma dose rates ranged from 56 to 193 n Gy h{sup -1}. Results indicated that lifetime effective dose to inhabitants of Chihuahua City is in average of 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of activity concentrations in soil were 51.8, 73.1, and 1096.5 Bq kg{sup -1}, of {sup 226}Ra, {sup 232}Th and {sup 40}K, respectively. From the analysis of the spatial distribution of {sup 232}Th, {sup 226}Ra, and {sup 40}K is to north, to north-center, and to south of city, respectively. In conclusion, natural background gamma dose received by inhabitants of Chihuahua City is high and mainly due to geological characteristics of the zone. (Author)

  2. Lifetime Effective Dose Assessment Based on Background Outdoor Gamma Exposure in Chihuahua City, Mexico

    Directory of Open Access Journals (Sweden)

    Sergio Luevano-Gurrola

    2015-09-01

    Full Text Available Determining ionizing radiation in a geographic area serves to assess its effects on a population’s health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the annual effective dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, the annual effective dose and the lifetime cancer risk, 48 sampling points were randomly selected in Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Müller counter. Outdoor gamma dose rates ranged from 113 to 310 nGy·h−1. At the same sites, 48 soil samples were taken to obtain the activity concentrations of 226Ra, 232Th and 40K and to calculate their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Calculated gamma dose rates ranged from 56 to 193 nGy·h−1. Results indicated that the lifetime effective dose of the inhabitants of Chihuahua City is on average 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of the activity concentrations in soil were 52, 73 and 1097 Bq·kg−1, for 226Ra, 232Th and 40K, respectively. From the analysis, the spatial distribution of 232Th, 226Ra and 40K is to the north, to the north-center and to the south of city, respectively. In conclusion, the natural background gamma dose received by the inhabitants of Chihuahua City is high and mainly due to the geological characteristics of the zone. From the radiological point of view, this kind of study allows us to identify the importance of manmade environments, which are often highly variable and difficult to characterize.

  3. Lifetime Effective Dose Assessment Based on Background Outdoor Gamma Exposure in Chihuahua City, Mexico.

    Science.gov (United States)

    Luevano-Gurrola, Sergio; Perez-Tapia, Angelica; Pinedo-Alvarez, Carmelo; Carrillo-Flores, Jorge; Montero-Cabrera, Maria Elena; Renteria-Villalobos, Marusia

    2015-09-30

    Determining ionizing radiation in a geographic area serves to assess its effects on a population's health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the annual effective dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, the annual effective dose and the lifetime cancer risk, 48 sampling points were randomly selected in Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Müller counter. Outdoor gamma dose rates ranged from 113 to 310 nGy·h(-1). At the same sites, 48 soil samples were taken to obtain the activity concentrations of (226)Ra, (232)Th and (40)K and to calculate their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Calculated gamma dose rates ranged from 56 to 193 nGy·h(-1). Results indicated that the lifetime effective dose of the inhabitants of Chihuahua City is on average 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of the activity concentrations in soil were 52, 73 and 1097 Bq·kg(-1), for (226)Ra, (232)Th and (40)K, respectively. From the analysis, the spatial distribution of (232)Th, (226)Ra and (40)K is to the north, to the north-center and to the south of city, respectively. In conclusion, the natural background gamma dose received by the inhabitants of Chihuahua City is high and mainly due to the geological characteristics of the zone. From the radiological point of view, this kind of study allows us to identify the importance of manmade environments, which are often highly variable and difficult to characterize.

  4. Lifetime Effective Dose Assessment Based on Background Outdoor Gamma Exposure in Chihuahua City, Mexico

    Science.gov (United States)

    Luevano-Gurrola, Sergio; Perez-Tapia, Angelica; Pinedo-Alvarez, Carmelo; Carrillo-Flores, Jorge; Montero-Cabrera, Maria Elena; Renteria-Villalobos, Marusia

    2015-01-01

    Determining ionizing radiation in a geographic area serves to assess its effects on a population’s health. The aim of this study was to evaluate the spatial distribution of the background environmental outdoor gamma dose rates in Chihuahua City. This study also estimated the annual effective dose and the lifetime cancer risks of the population of this city. To determine the outdoor gamma dose rate in air, the annual effective dose and the lifetime cancer risk, 48 sampling points were randomly selected in Chihuahua City. Outdoor gamma dose rate measurements were carried out by using a Geiger-Müller counter. Outdoor gamma dose rates ranged from 113 to 310 nGy·h−1. At the same sites, 48 soil samples were taken to obtain the activity concentrations of 226Ra, 232Th and 40K and to calculate their terrestrial gamma dose rates. Radioisotope activity concentrations were determined by gamma spectrometry. Calculated gamma dose rates ranged from 56 to 193 nGy·h−1. Results indicated that the lifetime effective dose of the inhabitants of Chihuahua City is on average 19.8 mSv, resulting in a lifetime cancer risk of 0.001. In addition, the mean of the activity concentrations in soil were 52, 73 and 1097 Bq·kg−1, for 226Ra, 232Th and 40K, respectively. From the analysis, the spatial distribution of 232Th, 226Ra and 40K is to the north, to the north-center and to the south of city, respectively. In conclusion, the natural background gamma dose received by the inhabitants of Chihuahua City is high and mainly due to the geological characteristics of the zone. From the radiological point of view, this kind of study allows us to identify the importance of manmade environments, which are often highly variable and difficult to characterize. PMID:26437425

  5. The location of uranium in source rocks and sites of secondary deposition at the Needle's Eye natural analogue site, Dumfries and Galloway

    International Nuclear Information System (INIS)

    Basham, I.R.; Hyslop, E.K.; Milodowski, A.E.; Pearce, J.M.

    1989-08-01

    The British Geological Survey has been conducting a co-ordinated research programme at the natural analogue site of Needle's Eye at Southwick on the Solway coast in SW Scotland. This study of a naturally radioactive geochemical system has been carried out with the aim of improving our confidence in using predictive models of radionuclide migration in the geosphere. This report describes results of integrated mineralogical techniques which have been applied to the study of both the 'source-term' and sites of secondary accumulation of uranium. Pitchblende in a polymetallic-carbonate breccia vein exposed in ancient sea-cliffs is the main source of labile uranium although other uranium-bearing minerals present in the granodiorite and hornfelsed siltstone host-rocks present probable ancillary leachable sites. In keeping with the complex chemistry of the primary sulphide-rich mineralization, a large variety of secondary U minerals has been recorded among which arsenates and hydrous silicates appear to predominate. Uranium transported in groundwaters draining the cliffs has accumulated in organic-rich estuarine/intertidal mudflat sediments of Quaternary age. Charged particle track registration techniques have demonstrated convincingly the effectiveness of humidified organic matter in retarding uranium transport and, coupled with scanning electron microscopy, have indicated an important role of living plants and bacteria in uranium uptake and concentration. (author)

  6. The location of uranium in source rocks and sites of secondary deposition at the Needle's Eye natural analogue site, Dumfries and Galloway

    International Nuclear Information System (INIS)

    Basham, I.R.; Hyslop, E.K.; Milodowski, A.E.; Pearce, J.M.

    1991-01-01

    The British Geological Survey has been conducting a coordinated research programme at the natural analogue site of Needle's Eye at Southwick on the Solway coast in south-west Scotland. This study of a naturally radioactive geochemical system has been carried out with the aim of improving our confidence in using predictive models of radionuclide migration in the geosphere. This report describes results of integrated mineralogical techniques which have been applied to the study of both the source-term and sites of secondary accumulation of uranium. Pitchblende in a polymetallic-carbonate breccia vein exposed in ancient sea-cliffs is the main source of labile uranium although other uranium-bearing minerals present in the granodiorite and hornfelsed siltstone host-rocks present probable ancillary leachable sites. In keeping with the complex chemistry of the primary sulphide-rich mineralization, a large variety of secondary U minerals has been recorded among which arsenates and hydrous silicates appear to predominate. Uranium transported in groundwaters draining the cliffs has accumulated in organic-rich estuarine/intertidal mudflat sediments of Quaternary age. Charged particle track registration techniques have demonstrated convincingly the effectiveness of humified organic matter in retarding uranium transport and, coupled with scanning electron microscopy, have indicated the important role of living plants and bacteria in uranium uptake and concentration. Computer codes used: CHEMVAL; CHEMTARD 5 figs.; 64 plates; 37 refs

  7. Rapid on-site detection of ephedrine and its analogues used as adulterants in slimming dietary supplements by TLC-SERS.

    Science.gov (United States)

    Lv, Diya; Cao, Yan; Lou, Ziyang; Li, Shujin; Chen, Xiaofei; Chai, Yifeng; Lu, Feng

    2015-02-01

    Ephedrine and its analogues are in the list of prohibited substance in adulteration to botanical dietary supplements (BDS) for their uncontrollable stimulating side effects. However, they were always adulterated illegally in BDS to promote losing weight. In order to avoid detection, various kinds of ephedrine analogues were added rather than ephedrine itself. This has brought about great difficulties in authentication of BDS. In this study, we put forward for the first time a method which combined thin-layer chromatography (TLC) and surface-enhanced Raman scattering (SERS) to directly identify trace adulterant. Ephedrine, pseudoephedrine, methylephedrine, and norephedrine were mixed and used in this method to develop an analytical model. As a result, the four analogues were separated efficiently in TLC analysis, and trace-components and low-background SERS detection was realized. The limit of detection (LOD) of the four analogues was 0.01 mg/mL. Eight common Raman peaks (△υ = 620, 1003, 1030, 1159, 1181, 1205, 1454, 1603 cm(-1)) were extracted experimentally and statistically to characterize the common feature of ephedrine analogues. A TLC-SERS method coupled with common-peak model was adopted to examine nine practical samples, two of which were found to be adulterated with ephedrine analogues. Identification results were then confirmed by UPLC-QTOF/MS analysis. The proposed method was simple, rapid, and accurate and can also be employed to trace adulterant identification even when there are no available reference derivatives on-site or unknown types of ephedrine analogues are adulterated.

  8. The Ruprechtov natural analogue site (Cz) study: mobile natural organic matter identification, characterisation and link to PA relevant processes - 16341

    International Nuclear Information System (INIS)

    Havlova, Vaclava; Cervinka, Radek; Noseck, Ulrich; Brasser, Thomas; Havel, Josef

    2009-01-01

    The Ruprechtov Natural Analogue (CZ) Programme has been focused on studying real system processes, relevant to performance assessment (PA) of sediment formations that can form the overburden of geological repository host rocks. The site has been extensively studied due to its geological constitution (granite - kaolin - clay - U mineralisation - organic matter). The presented study used Ruprechtov unique but well-described geological conditions in order to identify and characterise mobile organic matter (MOM) that can be easily released into groundwater and can influence PA relevant specie migration due to complexation/sorption reaction. The modem analytical method MALDI-TOF MS was used for characterisation. It was found that only a small fraction of sedimentary natural organic matter (NOM) from the site was easily releasable (max. 5%) as MOM, resulting in low organic substance concentration in natural groundwater. MOM amount released was decreasing with increasing NOM content. MALDI-TOF MS proved to be a useful tool to characterize organic substances, either natural ones or artificially released from natural organic matter samples. A noticeable fingerprint for all the MOM compounds analysed was found at MALDITOF MS spectra. This showed that MOM from the Ruprechtov site was in all cases composed of molecules with low molecular weight (under 1000 Da). As determined by the consequent geochemical analyses, despite groundwater reducing conditions MOM compounds would be mainly interacting with U(VI) in the groundwater, being present as more abundant U specie. Good correspondence of results enabled to consider the extracted humic acid HA 12/3 as a mobile organic matter fraction representative. (authors)

  9. The geology, hydrogeology and geochemistry of the Needle's Eye natural analogue site

    International Nuclear Information System (INIS)

    Hooker, P.J.

    1991-01-01

    The British Geological Survey has been carrying out a research investigation of the Needle's Eye site at Southwick on the Solway coast in south-western Scotland. This study of a naturally radioactive geochemical system has the aim of improving our confidence in using predictive models of radionuclide migration in the geosphere. This summary report describes results from the integrated use of hydrogeological, mineralogical and geochemical techniques applied to the study of the transport and distribution of uranium. Pitchblende veins exposed in the cliffs are a major source of soluble uranium in ground-waters flowing into organic-rich post-glacial flood plain and intertidal mudflat deposits. Organic matter both living and dead has played a key role in the retardation of uranium in these sediments. Chemical transport modelling of the uranium dispersion/retardation is described and the implications for performance assessment work are discussed. Computer codes used: CHEMVAL (thermodynamic data base constants). CHIMERE (chemical equilibrium code). METIS (flow code). PHREEQE (chemical equilibrium code). STELE (coupled chemical transport code)

  10. y Ciudad Juárez, Chihuahua

    Directory of Open Access Journals (Sweden)

    Socorro Arzaluz Solano

    2006-01-01

    Full Text Available El artículo aborda la aplicación del Programa Hábitat, diseñado por el Gobierno de Vicente Fox en 2002, en dos ciudades fronterizas: Nogales, Sonora, y Ciudad Juárez, Chihuahua. Se analiza la implantación del programa atendiendo sus particularidades, entre otros aspectos, se señalan los diferentes agentes que intervinieron en la ejecución de Hábitat, que pese a la claridad de las reglas, fueron diferentes en cada caso. También, las forma s de participación ciudadana promovidas por los gobiernos locales en ambos casos. Se presentan una reflexión final sobre el desarrollo de Hábitat en la frontera norte, y algunas recomendaciones.

  11. Chihuahua: a water reuse case in the desert.

    Science.gov (United States)

    Espino, M S; Navarro, C J; Pérez, J M

    2004-01-01

    Water supply for all kind of uses in Chihuahua is mainly groundwater. During the last decade this city has been damaged with a heavy hydrologic crisis because of a persistent drought. This came up with the overexploitation of groundwater aquifers; therefore a deficit between demand and offer was done. To minimize this problem the government authorities have started an integral plan of optimizing hydrologic resources which considers the treatment of wastewater and the use of reclaimed water. The secondary wastewater treatment facility of the city treats about 30,000 m3/d of a wastewater with high organic contents, and produces an effluent with low concentration of suspended solids, organic matter, fats, detergents, and metals. Reclaimed water is conveyed toward strategic sites for the irrigation of great green areas in sport clubs, educational institutions and industrial zones, besides of its utilization on some manufacturing processes, road service, and also over construction industry. The potential reuse of this water goes farther from those activities; the treatment of the secondary effluent until the required levels of the water-bearing recharge criteria are met for drinking water supply is considered as the next step to achieve through a suitable planning strategy for the best integral resource advantage.

  12. "The State of Chihuahua", Lesson Plan for "Cultural Unit: Focus on Mexico."

    Science.gov (United States)

    Llewellyn, Marianne

    This lesson plan was designed for students in Montana schools. The objectives for this culture unit are having: (1) students recognize the similarities between their home stat of Montana and the Mexican state of Chihuahua; (2) students learn about features unique to Chihuahua; and (3) students create an advertising brochure marketing Chihuahua to…

  13. Evaluation of meteorites as habitats for terrestrial microorganisms: Results from the Nullarbor Plain, Australia, a Mars analogue site

    Science.gov (United States)

    Tait, Alastair W.; Wilson, Siobhan A.; Tomkins, Andrew G.; Gagen, Emma J.; Fallon, Stewart J.; Southam, Gordon

    2017-10-01

    Unambiguous identification of biosignatures on Mars requires access to well-characterized, long-lasting geochemical standards at the planet's surface that can be modified by theoretical martian life. Ordinary chondrites, which are ancient meteorites that commonly fall to the surface of Mars and Earth, have well-characterized, narrow ranges in trace element and isotope geochemistry compared to martian rocks. Given that their mineralogy is more attractive to known chemolithotrophic life than the basaltic rocks that dominate the martian surface, exogenic rocks (e.g., chondritic meteorites) may be good places to look for signs of prior life endemic to Mars. In this study, we show that ordinary chondrites, collected from the arid Australian Nullarbor Plain, are commonly colonized and inhabited by terrestrial microorganisms that are endemic to this Mars analogue site. These terrestrial endolithic and chasmolithic microbial contaminants are commonly found in close association with hygroscopic veins of gypsum and Mg-calcite, which have formed within cracks penetrating deep into the meteorites. Terrestrial bacteria are observed within corrosion cavities, where troilite (FeS) oxidation has produced jarosite [KFe3(SO4)2(OH)6]. Where terrestrial microorganisms have colonized primary silicate minerals and secondary calcite, these mineral surfaces are heavily etched. Our results show that inhabitation of meteorites by terrestrial microorganisms in arid environments relies upon humidity and pH regulation by minerals. Furthermore, microbial colonization affects the weathering of meteorites and production of sulfate, carbonate, Fe-oxide and smectite minerals that can preserve chemical and isotopic biosignatures for thousands to millions of years on Earth. Meteorites are thus habitable by terrestrial microorganisms, even under highly desiccating environmental conditions of relevance to Mars. They may therefore be useful as chemical and isotopic ;standards; that preserve evidence of

  14. Characterization of urban solid waste in Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Gomez, Guadalupe; Meneses, Montserrat; Ballinas, Lourdes; Castells, Francesc

    2008-01-01

    The characterization of urban solid waste generation is fundamental for adequate decision making in the management strategy of urban solid waste in a city. The objective of this study is to characterize the waste generated in the households of Chihuahua city, and to compare the results obtained in areas of the city with three different socioeconomic levels. In order to identify the different socioeconomic trends in waste generation and characterization, 560 samples of solid waste were collected during 1 week from 80 households in Chihuahua and were hand sorted and classified into 15 weighted fractions. The average waste generation in Chihuahua calculated in this study was 0.676 kg per capita per day in April 2006. The main fractions were: organic (48%), paper (16%) and plastic (12%). Results show an increased waste generation associated with the socioeconomic level. The characterization in amount and composition of urban waste is the first step needed for the successful implementation of an integral waste management system

  15. Characterization of urban solid waste in Chihuahua, Mexico.

    Science.gov (United States)

    Gomez, Guadalupe; Meneses, Montserrat; Ballinas, Lourdes; Castells, Francesc

    2008-12-01

    The characterization of urban solid waste generation is fundamental for adequate decision making in the management strategy of urban solid waste in a city. The objective of this study is to characterize the waste generated in the households of Chihuahua city, and to compare the results obtained in areas of the city with three different socioeconomic levels. In order to identify the different socioeconomic trends in waste generation and characterization, 560 samples of solid waste were collected during 1 week from 80 households in Chihuahua and were hand sorted and classified into 15 weighted fractions. The average waste generation in Chihuahua calculated in this study was 0.676 kg per capita per day in April 2006. The main fractions were: organic (48%), paper (16%) and plastic (12%). Results show an increased waste generation associated with the socioeconomic level. The characterization in amount and composition of urban waste is the first step needed for the successful implementation of an integral waste management system.

  16. [3H]naloxone as an opioid receptor label: Analysis of binding site heterogeneity and use for determination of opioid affinities of casomorphin analogues

    International Nuclear Information System (INIS)

    Schnittler, M.; Repke, H.; Liebmann, C.; Schrader, U.; Schulze, H.P.; Neubert, K.

    1990-01-01

    The nonselective antagonist [ 3 H]naloxone was used to identify opioid receptors in rat brain membranes. The multiple naloxone binding sites were related to different opioid receptors by means of selective opiod ligands as well as various β-casomorphin analogues. Analysis of binding site heterogeneity was performed using several computer curve fitting methods. The results indicate that structurally modified casomorphin peptides are able to discriminate between μ 1 and μ 2 binding sites. The affinities to the μ sites obtained with [ 3 H]naloxone as label are in a good agreement with those from experiments with the μ selective radioligand [ 3 H]DAGO. The μ 1 site affinities of these casomorphin derivatives are well correlated with their antinociceptive potencies. This finding suggests the mediation of the analgesic activity via the high-affinity μ 1 subtype. (author)

  17. Amphibians and reptiles of the state of Chihuahua, Mexico, with comparisons with adjoining states

    Directory of Open Access Journals (Sweden)

    Julio A. Lemos-Espinal

    2017-02-01

    Full Text Available Chihuahua is Mexico’s largest state, and its physiographic complexity affects the distribution of its herpetofauna. We list amphibians and reptiles for the state of Chihuahua, with their conservation status. We also compare this list to those of six adjoining states in the United States and Mexico (New Mexico, Texas, Coahuila, Durango, Sinaloa, and Sonora. A total of 175 species of amphibians and reptiles is found in Chihuahua. Thirty-eight are amphibians, and 137 reptiles. Chihuahuan amphibians and reptiles represent just over 37% of such species from Chihuahua and neighboring states. Chihuahua shares the highest proportion of its herpetofauna with Sonora and Durango. Most of the herpetofauna of Chihuahua falls in IUCNs least concern category and is not listed by SEMARNAT. However, turtles in Chihuahua are a group of particular conservation concern.

  18. Amphibians and reptiles of the state of Chihuahua, Mexico, with comparisons with adjoining states.

    Science.gov (United States)

    Lemos-Espinal, Julio A; Smith, Geoffrey R; Woolrich-Piña, Guillermo A; Cruz, Alexander

    2017-01-01

    Chihuahua is Mexico's largest state, and its physiographic complexity affects the distribution of its herpetofauna. We list amphibians and reptiles for the state of Chihuahua, with their conservation status. We also compare this list to those of six adjoining states in the United States and Mexico (New Mexico, Texas, Coahuila, Durango, Sinaloa, and Sonora). A total of 175 species of amphibians and reptiles is found in Chihuahua. Thirty-eight are amphibians, and 137 reptiles. Chihuahuan amphibians and reptiles represent just over 37% of such species from Chihuahua and neighboring states. Chihuahua shares the highest proportion of its herpetofauna with Sonora and Durango. Most of the herpetofauna of Chihuahua falls in IUCNs least concern category and is not listed by SEMARNAT. However, turtles in Chihuahua are a group of particular conservation concern.

  19. Analogue Gravity

    Directory of Open Access Journals (Sweden)

    Barceló Carlos

    2005-12-01

    Full Text Available Analogue models of (and for gravity have a long and distinguished history dating back to the earliest years of general relativity. In this review article we will discuss the history, aims, results, and future prospects for the various analogue models. We start the discussion by presenting a particularly simple example of an analogue model, before exploring the rich history and complex tapestry of models discussed in the literature. The last decade in particular has seen a remarkable and sustained development of analogue gravity ideas, leading to some hundreds of published articles, a workshop, two books, and this review article. Future prospects for the analogue gravity programme also look promising, both on the experimental front (where technology is rapidly advancing and on the theoretical front (where variants of analogue models can be used as a springboard for radical attacks on the problem of quantum gravity.

  20. Affinity of vitamin E analogues for the ubiquinone complex II site correlates with their toxicity to cancer cells

    Czech Academy of Sciences Publication Activity Database

    Neužil, Jiří; Černý, Jiří; Dyason, J.C.; Dong, L.-F.; Ralph, S.J.

    2011-01-01

    Roč. 55, č. 10 (2011), s. 1543-1551 ISSN 1613-4125 Institutional research plan: CEZ:AV0Z50520701 Keywords : Vitamin E analogues * mitochondrial complex II * modelling Subject RIV: CE - Biochemistry Impact factor: 4.301, year: 2011

  1. Analogue Gravity

    Directory of Open Access Journals (Sweden)

    Carlos Barceló

    2011-05-01

    Full Text Available Analogue gravity is a research programme which investigates analogues of general relativistic gravitational fields within other physical systems, typically but not exclusively condensed matter systems, with the aim of gaining new insights into their corresponding problems. Analogue models of (and for gravity have a long and distinguished history dating back to the earliest years of general relativity. In this review article we will discuss the history, aims, results, and future prospects for the various analogue models. We start the discussion by presenting a particularly simple example of an analogue model, before exploring the rich history and complex tapestry of models discussed in the literature. The last decade in particular has seen a remarkable and sustained development of analogue gravity ideas, leading to some hundreds of published articles, a workshop, two books, and this review article. Future prospects for the analogue gravity programme also look promising, both on the experimental front (where technology is rapidly advancing and on the theoretical front (where variants of analogue models can be used as a springboard for radical attacks on the problem of quantum gravity.

  2. Characterization of uranium minerals from Chihuahua using synchrotron radiation

    International Nuclear Information System (INIS)

    Burciaga V, D. C.; Reyes C, M.; Reyes R, A.; Renteria V, M.; Esparza P, H.; Fuentes C, L.; Fuentes M, L; Silva S, M.; Herrera P, E.; Munoz, A.; Montero C, M. E.

    2010-01-01

    Uranium mineral deposits in the vicinity of Chihuahua City (northern Mexico) have motivated a multidisciplinary investigation due to their tech no-environmental importance. It provides a broad scope study of representative mineral samples extracted from the San Marcos deposit, located northwest of Chihuahua City. The zone of interest is the source of the Sacramento River, which runs at Chihuahua City. The high uranium content of the San Marcos deposit, which was formed by hydrothermal mineralization, has resulted in elevated levels of uranium in surface and ground water, fish, plants and sediments in this region. Mineral identification of the uranium-bearing phases was accomplished with a suite of techniques. Among these phases are those called meta tyuyamunite (Ca(UO 2 ) 2 (VO 4 ) 2 ·3-5 H 2 O) and becquerelite [Ca(UO 2 ) 6 O 4 (OH) 6 ·8(H 2 O)]. It was decided to study an almost pure meta tyuyamunite sample extracted from Pena Blanca, Chihuahua uranium ore and to synthesize the becquerelite, using a modified procedure from a published one. In the current work the crystal structure of meta tyuyamunite is presented, resolved by the Rietveld refinement. Both samples were studied by X-ray absorption fine structure at beamline 2-3, Stanford Synchrotron Radiation Light source. In the present work both the spectra and extended X-ray absorption fine structure parameters are presented. (Author)

  3. Characterization of uranium minerals from Chihuahua using synchrotron radiation

    Energy Technology Data Exchange (ETDEWEB)

    Burciaga V, D. C.; Reyes C, M.; Reyes R, A.; Renteria V, M.; Esparza P, H.; Fuentes C, L.; Fuentes M, L; Silva S, M.; Herrera P, E.; Munoz, A.; Montero C, M. E. [Centro de Investigacion en Materiales Avanzados, S. C., Miguel de Cervantes 120, Complejo Industrial Chihuahua, Chihuahua (Mexico)

    2010-02-15

    Uranium mineral deposits in the vicinity of Chihuahua City (northern Mexico) have motivated a multidisciplinary investigation due to their tech no-environmental importance. It provides a broad scope study of representative mineral samples extracted from the San Marcos deposit, located northwest of Chihuahua City. The zone of interest is the source of the Sacramento River, which runs at Chihuahua City. The high uranium content of the San Marcos deposit, which was formed by hydrothermal mineralization, has resulted in elevated levels of uranium in surface and ground water, fish, plants and sediments in this region. Mineral identification of the uranium-bearing phases was accomplished with a suite of techniques. Among these phases are those called meta tyuyamunite (Ca(UO{sub 2}){sub 2}(VO{sub 4}){sub 2{center_dot}}3-5 H{sub 2}O) and becquerelite [Ca(UO{sub 2}){sub 6}O{sub 4}(OH){sub 6{center_dot}}8(H{sub 2}O)]. It was decided to study an almost pure meta tyuyamunite sample extracted from Pena Blanca, Chihuahua uranium ore and to synthesize the becquerelite, using a modified procedure from a published one. In the current work the crystal structure of meta tyuyamunite is presented, resolved by the Rietveld refinement. Both samples were studied by X-ray absorption fine structure at beamline 2-3, Stanford Synchrotron Radiation Light source. In the present work both the spectra and extended X-ray absorption fine structure parameters are presented. (Author)

  4. Radioactive hydrogeochemical processes in the Chihuahua-Sacramento Basin, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Burillo, J. C.; Reyes C, M.; Montero C, M. E.; Renteria V, M.; Herrera P, E. F. [Centro de Investigacion en Materiales Avanzados, S. C., Miguel de Cervantes No. 120, Complejo Industrial Chihuahua, 31109 Chihuahua (Mexico); Reyes, I.; Espino, M. S., E-mail: elena.montero@cimav.edu.mx [Universidad Autonoma de Chihuahua, Facultad de Ingenieria, Nuevo Campus Universitario, Chihuahua (Mexico)

    2012-06-15

    The Chihuahua Basin is divided by its morphology into three main sub basins: Chihuahua-Sacramento sub basin, Chihuahua Dam sub basin and Chuviscar River sub basin. In the aquifers at the Sacramento sub basin, specific concentrations of uranium in groundwater range from 460 to 1260 Bq / m{sup 3}. The presence of strata and sandy clay lenses with radiometric anomalies in the N W of Chihuahua Valley was confirmed by a litostatigraphic study and gamma spectrometry measurements of drill cuttings. High uranium activity values found in the water of some deep wells may correspond to the presence of fine material bodies of carbonaceous material, possible forming pa leo-sediment of flooding or pa leo-soils. It is suggested that these clay horizons are uranyl ion collectors. Uranyl may suffer a reduction process by organic material. Furthermore the groundwater, depending on its ph and Eh, oxidizes and re-dissolves uranium. The hydrogeochemical behavior of San Marcos dam and the N W Valley area is the subject of studies that should help to clarify the origin of the radioactive elements and their relationships with other pollutants in the watershed. (Author)

  5. PROTEIN & SENSORY ANALYSIS TO CHARACTERIZE MEXICAN CHIHUAHUA CHEESES

    Science.gov (United States)

    It has been established that native microflora in raw milk cheeses, including Queso Chihuahua, a Mexican cheese variety, contributes to the development of unique flavors through degradation of milk proteins resulting in the release of free amino acids and short peptides that influence the taste and ...

  6. Radioactive hydrogeochemical processes in the Chihuahua-Sacramento Basin, Mexico

    International Nuclear Information System (INIS)

    Burillo, J. C.; Reyes C, M.; Montero C, M. E.; Renteria V, M.; Herrera P, E. F.; Reyes, I.; Espino, M. S.

    2012-01-01

    The Chihuahua Basin is divided by its morphology into three main sub basins: Chihuahua-Sacramento sub basin, Chihuahua Dam sub basin and Chuviscar River sub basin. In the aquifers at the Sacramento sub basin, specific concentrations of uranium in groundwater range from 460 to 1260 Bq / m 3 . The presence of strata and sandy clay lenses with radiometric anomalies in the N W of Chihuahua Valley was confirmed by a litostatigraphic study and gamma spectrometry measurements of drill cuttings. High uranium activity values found in the water of some deep wells may correspond to the presence of fine material bodies of carbonaceous material, possible forming pa leo-sediment of flooding or pa leo-soils. It is suggested that these clay horizons are uranyl ion collectors. Uranyl may suffer a reduction process by organic material. Furthermore the groundwater, depending on its ph and Eh, oxidizes and re-dissolves uranium. The hydrogeochemical behavior of San Marcos dam and the N W Valley area is the subject of studies that should help to clarify the origin of the radioactive elements and their relationships with other pollutants in the watershed. (Author)

  7. Structure of Bacillus subtilis γ-glutamyltranspeptidase in complex with acivicin: diversity of the binding mode of a classical and electrophilic active-site-directed glutamate analogue

    International Nuclear Information System (INIS)

    Ida, Tomoyo; Suzuki, Hideyuki; Fukuyama, Keiichi; Hiratake, Jun; Wada, Kei

    2014-01-01

    The binding modes of acivicin, a classical and an electrophilic active-site-directed glutamate analogue, to bacterial γ-glutamyltranspeptidases were found to be diverse. γ-Glutamyltranspeptidase (GGT) is an enzyme that plays a central role in glutathione metabolism, and acivicin is a classical inhibitor of GGT. Here, the structure of acivicin bound to Bacillus subtilis GGT determined by X-ray crystallography to 1.8 Å resolution is presented, in which it binds to the active site in a similar manner to that in Helicobacter pylori GGT, but in a different binding mode to that in Escherichia coli GGT. In B. subtilis GGT, acivicin is bound covalently through its C3 atom with sp 2 hybridization to Thr403 O γ , the catalytic nucleophile of the enzyme. The results show that acivicin-binding sites are common, but the binding manners and orientations of its five-membered dihydroisoxazole ring are diverse in the binding pockets of GGTs

  8. Mauna Kea, Hawaii as an Analogue Site for Future Planetary Resource Exploration: Results from the 2010 ILSO-ISRU Field-Testing Campaign

    Science.gov (United States)

    ten Kate, I. L.; Armstrong, R.; Bernhardt, B.; Blummers, M.; Boucher, D.; Caillibot, E.; Captain, J.; Deleuterio, G.; Farmer, J. D.; Glavin, D. P.; hide

    2010-01-01

    Within the framework of the International Lunar Surface Operation - In-Situ Resource Utilization Analogue Test held on January 27 - February 11, 2010 on the Mauna Kea volcano in Hawaii, a number of scientific instrument teams collaborated to characterize the field site and test instrument capabilities outside laboratory environments. In this paper, we provide a geological setting for this new field-test site, a description of the instruments that were tested during the 2010 ILSO-ISRU field campaign, and a short discussion for each instrument about the validity and use of the results obtained during the test. These results will form a catalogue that may serve as reference for future test campaigns. In this paper we provide a description and regional geological setting for a new field analogue test site for lunar resource exploration, and discuss results obtained from the 2010 ILSO-ISRU field campaign as a reference for future field-testing at this site. The following instruments were tested: a multispectral microscopic imager, MMI, a Mossbauer spectrometer, an evolved gas analyzer, VAPoR, and an oxygen and volatile extractor called RESOLVE. Preliminary results show that the sediments change from dry, organic-poor, poorly-sorted volcaniclastic sand on the surface, containing basalt, iron oxides and clays, to more water- and organic-rich, fine grained, well-sorted volcaniclastic sand, primarily consisting of iron oxides and depleted of basalt and clays. Furthermore, drilling experiments showed a very close correlation between drilling on the Moon and drilling at the test site. The ILSO-ISRU test site was an ideal location for testing strategies for in situ resource exploration at the lunar or martian surface.

  9. 1H nuclear magnetic resonance studies of the conformation of an ATP analogue at the active site of Na,K-ATPase from kidney medulla

    International Nuclear Information System (INIS)

    Stewart, J.M.M.; Grisham, C.M.

    1988-01-01

    1 H nuclear magnetic relaxation measurements have been used to determine the three-dimensional conformation of an ATP analogue, Co(NH 3 ) 4 ATP, at the active site of sheep kidney Na,K-ATPase. Previous studies have shown that Co(NH 4 ) 4 ATP is a competitive inhibitor with respect to MnATP for the Na,K-ATPase and that Mn 2+ bound to a single, high-affinity site on the ATPase can be an effective paramagnetic probe for nuclear relaxation studies of the Na-K-ATPase. From the paramagnetic effect of Mn 2+ bound to the APTase on the longitudinal relaxation rates of the protons of Co(NH 3 ) 4 ATP at the substrate site (at 300 and 361 MHz), Mn-H distances to seven protons on the bound nucleotide were determined. Taken together with previous 31 P nuclear relaxation data, these measurements are consistent with a single nucleotide conformation at the active site. The nucleotide adopts a bent configuration, in which the triphosphate chain lies nearly parallel to the adenine moiety. The glycosidic torsion angle is 35 0 , and the conformation of the ribose ring is slightly N-type. The bound Mn 2+ lies above and in the plane of the adenine ring. The distances from Mn 2+ to N 6 and N 7 are too large for first coordination sphere complexes but are appropriate for second-sphere complexes involving, for example, intervening hydrogen-bonded water molecules. The NMR data also indicate that the structure of the bound ATP analogue is independent of the conformational state of the enzyme

  10. /sup 1/H nuclear magnetic resonance studies of the conformation of an ATP analogue at the active site of Na,K-ATPase from kidney medulla

    Energy Technology Data Exchange (ETDEWEB)

    MacD. Stewart, J.M.; Grisham, C.M.

    1988-06-28

    /sup 1/H nuclear magnetic relaxation measurements have been used to determine the three-dimensional conformation of an ATP analogue, Co(NH/sub 3/)/sub 4/ATP, at the active site of sheep kidney Na,K-ATPase. Previous studies have shown that Co(NH/sub 4/)/sub 4/ATP is a competitive inhibitor with respect to MnATP for the Na,K-ATPase and that Mn/sup 2 +/ bound to a single, high-affinity site on the ATPase can be an effective paramagnetic probe for nuclear relaxation studies of the Na-K-ATPase. From the paramagnetic effect of Mn/sup 2 +/ bound to the APTase on the longitudinal relaxation rates of the protons of Co(NH/sub 3/)/sub 4/ATP at the substrate site (at 300 and 361 MHz), Mn-H distances to seven protons on the bound nucleotide were determined. Taken together with previous /sup 31/P nuclear relaxation data, these measurements are consistent with a single nucleotide conformation at the active site. The nucleotide adopts a bent configuration, in which the triphosphate chain lies nearly parallel to the adenine moiety. The glycosidic torsion angle is 35/sup 0/, and the conformation of the ribose ring is slightly N-type. The bound Mn/sup 2 +/ lies above and in the plane of the adenine ring. The distances from Mn/sup 2 +/ to N/sub 6/ and N/sub 7/ are too large for first coordination sphere complexes but are appropriate for second-sphere complexes involving, for example, intervening hydrogen-bonded water molecules. The NMR data also indicate that the structure of the bound ATP analogue is independent of the conformational state of the enzyme.

  11. Sorption studies of uranium in sediment-groundwater systems from the natural analogue sites of Needle's Eye and Broubster

    International Nuclear Information System (INIS)

    Higgo, J.J.; Falck, W.E.; Hooker, P.J.

    1990-01-01

    This report describes the results of sorption experiments designed to provide essential data for migration modelling. Sorption of 233 U from natural ground-water onto peat from Broubster and silt from Needle's Eye was studied under atmospheric conditions and different pH regimes. The temperature was maintained at 10 0 C and, in the case of Needle's Eye silt, the kinetics of sorption were followed. The results were analyzed in conjunction with speciation modelling in an attempt to understand the sorption mechanisms and to extrapolate the findings to cover the range of conditions likely to be met in the field. This work is part of the CEC project Mirage - Second phase, research area 'Natural analogues'

  12. Neuroaxonal Dystrophy and Cavitating Leukoencephalopathy of Chihuahua Dogs.

    Science.gov (United States)

    Degl'Innocenti, Sara; Asiag, Nimrod; Zeira, Offer; Falzone, Cristian; Cantile, Carlo

    2017-09-01

    A novel form of neuroaxonal dystrophy is described in 3 Chihuahua pups, 2 of which were from the same litter. It was characterized not only by accumulation of numerous and widely distributed axonal swellings (spheroids) but also by a severe cavitating leukoencephalopathy. The dogs presented with progressive neurological signs, including gait abnormalities and postural reaction deficits. Magnetic resonance images and gross examination at necropsy revealed dilation of lateral ventricles and cerebral atrophy, accompanied by cavitation of the subcortical white matter. Histopathologically, severe axonal degeneration with formation of large spheroids was found in the cerebral and cerebellar white matter, thalamus, and brainstem nuclei. Small-caliber spheroids were observed in the cerebral and cerebellar gray matter. The telencephalic white matter had severe myelin loss and cavitation with relative sparing of the U-fibers. Different from previously reported cases of canine neuroaxonal dystrophy, in these Chihuahuas the spheroid distribution predominantly involved the white matter with secondary severe leukoencephalopathy.

  13. Dose by 222 Rn in houses of the Chihuahua city

    International Nuclear Information System (INIS)

    Colmenero S, L.H.; Talamantes F, C.; Villalba, M.L.; Dobson, P.F.; Ortalejo M, B.

    2007-01-01

    Full text: The dose equivalent that the population of the Chihuahua city receives due to the radon in air that joined to values of uranium, thorium and potassium due to the floor and radon in water was determined, they give values very above the international and national norms. The state of Chihuahua contains near 56 locations distributed by the whole state. The city of Chihuahua, capital of the state, is surrounded of rocks with great content of uranium, for what their floor also contains to the 226 Ra that generates to the 222 Rn. The construction of the housings of the city of Chihuahua is mainly of brick, block and adobe; the material to elaborate them is take from the rocks and floor of the surroundings, this makes that the radon is presented in a great quantity of houses of this city. As the floor and water they also contain those natural radionuclides, the total dose equivalent that the inhabitants receive is bigger to other cities of the country. Diverse international organizations dedicated to the radioactivity, indicate that the level of the 222 Rn should not surpass the 148 Bq/m 3 , since this gas produces lung cancer. The state of Chihuahua has an index of deaths on the average by lung cancer of double the national average, the capital of the state also has a high index. The radon concentration in a house depends on the construction material with which was made, as well as of the existent climatic conditions. During the day, this concentration depends mainly on the interior temperature, so during the night and dawn increases the radon concentration. The radon is the biggest source of radioactive dose received by the human being and it can generate a problem of public health if the concentration is high during enough time, for what the city of Chihuahua has the geologic and climatic characteristics to have it. This study was carried out in 50 house-room of the city of Chihuahua. Built houses with brick, block and adobe were selected. The quantification

  14. Wind Transport of Radionuclide- Bearing Dust, Peña Blanca, Chihuahua, Mexico

    Science.gov (United States)

    Velarde, R.; Goodell, P. C.; Gill, T. E.; Arimoto, R.

    2007-05-01

    This investigation evaluates radionuclide fractionation during wind erosion of high-grade uranium ore storage piles at Peña Blanca (50km north of Chihuahua City), Chihuahua, Mexico. The aridity of the local environment promotes dust resuspension by high winds. Although active operations ceased in 1983, the Peña Blanca mining district is one of Mexico`s most important uranium ore reserves. The study site contains piles of high grade ore, left loose on the surface, and separated by the specific deposits from which they were derived (Margaritas, Nopal I, and Puerto I). Similar locations do not exist in the United States, since uranium mining sites in the USA have been reclaimed. The Peña Blanca site serves as an analog for the Yucca Mountain project. Dust deposition is collected at Peña Blanca with BSNE sediment catchers (Fryrear, 1986) and marble dust traps (Reheis, 1999). These devices capture windblown sediment; subsequently, the sample data will help quantify potentially radioactive short term field sediment loss from the repository surface and determine sediment flux. Aerosols and surface materials will be analyzed and radioactivity levels established utilizing techniques such as gamma spectroscopy. As a result, we will be able to estimate how much radionuclide contaminated dust is being transported or attached geochemically to fine grain soils or minerals (e.g., clays or iron oxides). The high-grade uranium-bearing material is at secular equilibrium, thus the entire decay series is present. Of resulting interest is not only the aeolian transport of uranium, but also of the other daughter products. These studies will improve our understanding of geochemical cycling of radionuclides with respect to sources, transport, and deposition. The results may also have important implications for the geosciences and homeland security, and potential applications to public health. Funding for this project is provided in part via a NSF grant to Arimoto.

  15. Alternative perspectives of quality of prenatal care in Chihuahua, Mexico

    OpenAIRE

    Lourdes Camarena O; Christine von Glascoe

    2007-01-01

    Objective: this article describes the process and results of a research on the quality of prenatal care from the perspective of pregnant women who use the principal subsystems of the Mexican healthcare system in the city of Chihuahua, Mexico. Methodology: the field of cognitive anthropology was adopted using techniques that reveal the organization of concepts of quality in prenatal care based on pregnant women’s knowledge and experience, in terms of where they decided to seek care. Results: a...

  16. Evaluation of host rocks and background lithologies as secondary contributors to the uranium and rare-earth element source-term at the Needle's Eye natural analogue site

    International Nuclear Information System (INIS)

    Hyslop, E.K.

    1993-01-01

    HMIP has a research programme investigating some naturally radioactive sites in the UK as geochemical analogues of radionuclide migration. The objective is to test thermodynamic database and computer codes used for modelling radionuclide migration under environmental conditions. This report describes a study of the distributions of uranium (U) and the rare-earth elements (REE) in the vicinity of pitchblende veins outcropping in the cliff at Needle's Eye on the Solway Coats, SW Scotland. This report improves the information available on the secondary source-terms of U and REE. The minerals in the country rocks are thought to be supplying only minor amounts of these elements to the groundwaters flowing into the Merse silts within the detailed study area close to the mineralisation in the cliff. The pitchblende veins are the principal source-term for U migrating into the Merse silts at the foot of the cliff. (author)

  17. BALANOL ANALOGUES

    DEFF Research Database (Denmark)

    1997-01-01

    The present invention relates to a solid phase methodology for the preparation of a combinatorial library of structural analogues of the natural product balanol (ophiocordin, azepinostatin), which is a protein kinase C (PKC) and protein kinase A (PKA) inhibitor. The method comprises solid...

  18. Microbiological analysis at the Osamu Utsumi mine and Morro do Ferro analogue study sites, Pocos de Caldas, Brazil

    International Nuclear Information System (INIS)

    West, J.M.; Vialta, A.; McKinley, I.G.

    1990-01-01

    The Pocos de Caldas project is a wide-ranging natural analogue study focussed on a number of areas of concern in the performance assessment of the disposal of radioactive waste. Part of the work has involved characterising microbial populations and their influence in various processes. Core material and groundwaters have been sampled for microbiological content at various depths form boreholes at the Osamu Utsumi open pit uranium mine and Morro do Ferro Th/REE ore body. Microbes were found in all samples but numbers do not appear to be related to depth. Analyses of groundwaters gave higher numbers than with solid material and demonstrated the presence of sulphur cycle bacteria. These observations have been compared with predictions of a model used in performance assessment to calculate the maximum biomass/microbial activity based on constraints set by available nutrients and energy. The main conclusions of this analysis are: 1. Low microbial activities can be supported by the energy and nutrients supplied by alteration processes at or around the redox front. The maximum annual production of approximately equal to 0.01 - 0.1 g biomass (dry)/m 2 of redox front is in reasonable agreement with observed standing populations. 2. The presence of high concentrations of sulphate reducing bacteria around the redox front indicate a complex sulphur geochemistry which may be predominantly microbially catalysed and could explain the nodular form of pitchblende concretions and the presence of secondary pyrite. 3. There is little trace element mobilisation by organic byproducts and the main role of microbes in this system is to catalyse specific redox reactions. (au)

  19. Structure of Bacillus subtilis γ-glutamyltranspeptidase in complex with acivicin: diversity of the binding mode of a classical and electrophilic active-site-directed glutamate analogue

    Energy Technology Data Exchange (ETDEWEB)

    Ida, Tomoyo [Osaka University, Toyonaka, Osaka 560-0043 (Japan); Suzuki, Hideyuki [Kyoto Institute of Technology, Goshokaido-cho, Matsugasaki, Sakyo-ku, Kyoto 606-8585 (Japan); Fukuyama, Keiichi [Osaka University, Toyonaka, Osaka 560-0043 (Japan); Hiratake, Jun [Kyoto University, Uji, Kyoto 611-0011 (Japan); Wada, Kei, E-mail: keiwada@med.miyazaki-u.ac.jp [University of Miyazaki, Miyazaki 889-1692 (Japan); Osaka University, Toyonaka, Osaka 560-0043 (Japan)

    2014-02-01

    The binding modes of acivicin, a classical and an electrophilic active-site-directed glutamate analogue, to bacterial γ-glutamyltranspeptidases were found to be diverse. γ-Glutamyltranspeptidase (GGT) is an enzyme that plays a central role in glutathione metabolism, and acivicin is a classical inhibitor of GGT. Here, the structure of acivicin bound to Bacillus subtilis GGT determined by X-ray crystallography to 1.8 Å resolution is presented, in which it binds to the active site in a similar manner to that in Helicobacter pylori GGT, but in a different binding mode to that in Escherichia coli GGT. In B. subtilis GGT, acivicin is bound covalently through its C3 atom with sp{sup 2} hybridization to Thr403 O{sup γ}, the catalytic nucleophile of the enzyme. The results show that acivicin-binding sites are common, but the binding manners and orientations of its five-membered dihydroisoxazole ring are diverse in the binding pockets of GGTs.

  20. Study of the sorption of actinide analogues on calcite and smectite as a model to predict the evolution of radioactive waste disposal in geological sites

    International Nuclear Information System (INIS)

    Budiman Sastrowardoyo, Pratomo

    1991-01-01

    In the framework of the problem of the radioactive waste disposal in deep geological sites, the purpose of this study is to predict the sorption of radionuclides on minerals within the geological barrier, after the rupture of the containers and the release of the radionuclides into underground water. Neodymium labelled by 147 Nd was used as an analogue of trivalent actinides. Calcite and smectite were used as examples of altered minerals of granitic sites. In simple media, neodymium is retained with a high affinity on both minerals. Fast kinetics of fixation, high distribution coefficients and sorption capacities are favorable factors for the slowing down of radionuclide migration in underground water. Fixation on calcite is quasi irreversible. A second kinetic step was observed, leading to an increase of the retention capacity. In the first step, this is probably a superficial sorption, but with a non-homogeneous affinity for sorption sites. An exchange mechanism of Nd 3+ with Na + et Ca 2+ ions of smectite occurs. The Freundlich isotherm observed for both minerals can be used for predicting the retention of radioelements as a function of their concentration and introducing these data in a migration model after comparison with the results of dynamic and field experiments. (author) [fr

  1. Natural Analogue Synthesis Report

    Energy Technology Data Exchange (ETDEWEB)

    A. M. Simmons

    2002-05-01

    The purpose of this report is to present analogue studies and literature reviews designed to provide qualitative and quantitative information to test and provide added confidence in process models abstracted for performance assessment (PA) and model predictions pertinent to PA. This report provides updates to studies presented in the ''Yucca Mountain Site Description'' (CRWMS M and O 2000 [151945], Section 13) and new examples gleaned from the literature, along with results of quantitative studies conducted specifically for the Yucca Mountain Site Characterization Project (YMP). The intent of the natural analogue studies was to collect corroborative evidence from analogues to demonstrate additional understanding of processes expected to occur during postclosure at a potential Yucca Mountain repository. The report focuses on key processes by providing observations and analyses of natural and anthropogenic (human-induced) systems to improve understanding and confidence in the operation of these processes under conditions similar to those that could occur in a nuclear waste repository. The process models include those that represent both engineered and natural barrier processes. A second purpose of this report is to document the various applications of natural analogues to geologic repository programs, focusing primarily on the way analogues have been used by the YMP. This report is limited to providing support for PA in a confirmatory manner and to providing corroborative inputs for process modeling activities. Section 1.7 discusses additional limitations of this report. Key topics for this report are analogues to emplacement drift degradation, waste form degradation, waste package degradation, degradation of other materials proposed for the engineered barrier, seepage into drifts, radionuclide flow and transport in the unsaturated zone (UZ), analogues to coupled thermal-hydrologic-mechanical-chemical processes, saturated zone (SZ) transport

  2. Energy saving programs and renewable energies in Chihuahua, Mexico; Programas de ahorro de energia y energias renovables en Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ibarra Noris, Jose Luis [Gobierno del Estado de Chihuahua (Mexico)

    2005-07-01

    The high index of economic and technological growth registered in the border zone of northern Mexico in the last years, has simultaneously caused an annual growth in the electrical energy demand in a percentage higher than 6%. In this document are included the economic and environmental impacts caused by the projects developed in the Chihuahua State on energy efficiency and on the available potential of renewable energies. In order to evaluate the environmental impact that is caused when saving electrical energy in the diverse projects in process, the emission of CO{sub 2} is the only emission taken into account (even though also emissions of SO{sub 2}, NO{sub 2} and Hg exist) for being this polluting agent the one that contributes in greater amount to the global warming and the greenhouse effect. The emission index of CO{sub 2} that we considered in this presentation is of 600 kg/mwh, on the basis of the type of fuel and volume of generation of the plants in operation of the Comision Federal de Electricidad (CFE) in the Chihuahua State. [Spanish] El alto indice de crecimiento economico y tecnologico registrado en la zona fronteriza del norte de Mexico en los ultimos anos, ha ocasionado paralelamente un crecimiento en la demanda de energia electrica superior al 6% anual. En este documento se incluyen los impactos economicos y ambientales de los proyectos que se desarrollan en el estado de Chihuahua en eficiencia energetica y en el potencial que se tiene de energias renovables. Para evaluar el impacto ambiental que se obtiene al ahorrar energia electrica en los diversos proyectos en proceso, se toma en cuenta unicamente emisiones de CO{sub 2} (aun cuando tambien existen emisiones de SO{sub 2}, NO{sub 2} y Hg) por ser este el contaminante que en mayor cantidad afecta al calentamiento global y al efecto invernadero. El indice de emisiones de CO{sub 2} que consideramos en esta presentacion es de 600 kg/mwh, en base al tipo de combustible y volumen de generacion de las

  3. Analogues of neuroactive polyamine wasp toxins that lack inner basic sites exhibit enhanced antagonism toward a muscle-type mammalian nicotinic acetylcholine receptor

    DEFF Research Database (Denmark)

    Stromgaard, K; Brierley, M J; Andersen, K

    1999-01-01

    noncompetitively antagonized the nicotinic acetylcholine receptor (nAChR) in a concentration-, time-, and voltage-dependent manner. The amplitudes of acetylcholine-induced currents were compared at their peaks and at the end of a 1 s application in the presence or absence of the analogues. Most of the analogues...

  4. NATURAL ANALOGUE SYNTHESIS REPORT

    International Nuclear Information System (INIS)

    Simmons, A.M.

    2004-01-01

    The purpose of this report is to present analogue studies and literature reviews designed to provide qualitative and quantitative information to test and provide added confidence in process models abstracted for performance assessment (PA) and model predictions pertinent to PA. This report provides updates to studies presented in the Yucca Mountain Site Description (CRWMS M and O 2000 [151945], Section 13) and new examples gleaned from the literature along with results of quantitative studies conducted specifically for the Yucca Mountain Project (YMP). The intent of the natural analogue studies was to collect corroborative evidence from analogues to demonstrate additional understanding of processes expected to occur during postclosure at a potential Yucca Mountain repository. The report focuses on key processes by providing observations and analyses of natural and anthropogenic (human-induced) systems to improve understanding and confidence in the operation of these processes under conditions similar to those that could occur in a nuclear waste repository. The process models include those that represent both engineered and natural barrier processes. A second purpose of this report is to document the various applications of natural analogues to geologic repository programs, focusing primarily on the way analogues have been used by the YMP. This report is limited to providing support for PA in a confirmatory manner and to providing corroborative inputs for process modeling activities. Section 1.7 discusses additional limitations of this report. Key topics for this report are analogues to emplacement-drift degradation, waste-form degradation, waste-package degradation, degradation of other materials proposed for the engineered barrier, seepage into drifts, radionuclide flow and transport in the unsaturated zone (UZ), analogues to coupled thermal-hydrologic-mechanical-chemical processes, saturated-zone (SZ) transport, impact of radionuclide release on the biosphere

  5. Compartmental HBV evolution and replication in liver and extrahepatic sites after nucleos/tide analogue therapy in chronic hepatitis B carriers.

    Science.gov (United States)

    Gao, Shan; Duan, Zhong-Ping; Chen, Yu; van der Meer, Frank; Lee, Samuel S; Osiowy, Carla; van Marle, Guido; Coffin, Carla S

    2017-09-01

    Hepatitis B virus (HBV) variants are associated with nucleos/tide analogue (NA) response and liver disease but it is unknown whether NA influences extrahepatic HBV persistence. To investigate HBV replication and genetic evolution in hepatic and extrahepatic sites of chronic hepatitis B (CHB) before and after NA therapy. A total of 13 paired plasma, peripheral blood mononuclear cells (PBMC), were collected from chronic HBV carriers at baseline and after a median 53 weeks NA therapy as well as liver biopsy (N=7 baseline, N=5 follow-up). HBV covalently closed circular DNA (cccDNA) and messenger (m) RNA in liver and PBMC were analyzed. HBV polymerase (P)/surface (S), basal core promoter (BCP)/pre-core (PC)/C gene clonal sequencing was done in plasma, peripheral blood mononuclear cells (PBMC), and liver. Compare to baseline, at ∼53 weeks follow-up, there was no significant change in HBV cccDNA levels in liver (0.2-0.08 copies/hepatocyte, p>0.05) or in PBMC 0.003-0.02 copies/PBMC, p>0.05), and HBV mRNA remained detectable in both sites. At baseline, BCP variants were higher in PBMC vs. liver and plasma. After therapy, drug resistant (DR) and immune escape (IE) variants increased in liver but IE and PC variants were more frequent in PBMC. HBV P/S diversity was significantly higher in PBMC compared to plasma. Continuous HBV replication occurs in liver and PBMC and shows compartmentalized evolution under selective pressure of potent NA therapy. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. Geochemical modelling of water-rock interactions at the Osamu Utsumi mine and Morro do Ferro analogue study sites, Pocos de Caldas, Brazil

    International Nuclear Information System (INIS)

    Nordstrom, D.K.; Puigdomenech, I.; McNutt, R.H.

    1990-01-01

    Geochemical processes involving water-rock interactions have been modelled using groundwater composition, mineralogical data, ion plots and computations of speciation, non-thermodynamic mass balance and thermodynamic mass transfer for two natural analogue sites near Pocos de Caldas, Brazil: the Osamu Utsumi mine and Morro do Ferro. The main rock type is an alkaline igneous complex composed of volcanic and sub-volcanic phonolites that have been hydrothermally altered and highly weathered. This altered rock mass grades from a laterite at the surface to a saprolite and finally to unweathered, hydrothermally altered bedrock at depth. The mine site contains high concentrations of uranium and Morro do Ferro contains high concentrations of thorium and rare-earths. The reaction models can reproduce the water chemistry and mineral occurences and they were validated by predicting the masses of minerals precipitated and the pH of the final water. The model computations can also reproduce the pH and iron concentrations of the water samples during CO 2 degassing and iron(II) oxidation from exposure to air. The results from the geochemical reaction models reveal that the dominant processes are production of CO 2 in the soil zone through aerobic decay of organic matter, dissolution of fluorite, calcite, K-feldspar, albite and manganese oxides, oxidation of pyrite and sphalerite and precipitation of ferric oxides, silica and kaolinite. Recharge waters are undersaturated with respect to barite and discharging waters and deeper groundwaters are saturated to supersaturated with respect to barite, demonstrating a strong equilibrium solubility control. Strontium isotope data demonstrate that sources other than calcium-bearing minerals are required to account for the dissolved strontium in the ground. These may include K-feldspar, smectite-chlorite mixed-layer clays and goyazite. (author) 24 figs., 4 tabs., 18 refs

  7. Primer registro de la cotorra argentina (Myiopsitta monachus en Chihuahua, México

    Directory of Open Access Journals (Sweden)

    Ricardo Abel Soto-Cruz

    2015-06-01

    Full Text Available Reportamos el primer registro de la cotorra argentina (Myiopsitta monachus en las ciudades de Chihuahua y Delicias en Chihuahua, México. Observamos cinco individuos de esta especie de junio a diciembre de 2011 en las instalaciones de la Facultad de Zootecnia y Ecología de la Universidad Autónoma de Chihuahua; grupos de 2 a 12 individuos en el área urbana de la ciudad de Chihuahua durante 2012, y cuatro individuos en ciudad Delicias, a 80 km al sureste de la ciudad de Chihuahua, en el 2013. Previamente, en enero de 2011, se reportó, en el portal electrónico de aVerAves, el avistamiento de un individuo en el noroeste del estado. Dada la presencia de nidos activos en las ciudades de Chihuahua y Delicias, la especie podría estar ya establecida en esta parte del país. Recomendamos dar seguimiento a las poblaciones existentes de esta especie a fin de documentar los posibles riesgos a los ecosistemas en la región.

  8. Immigrant children and school interculturality in northern Chihuahua

    Directory of Open Access Journals (Sweden)

    Tamara Segura Herrera

    2018-09-01

    Full Text Available In the Mexican context, interculturality represents a discourse of recognition and respect for cultural diversity, in particular of indigenous peoples. The purpose of this article is to explore how interculturality among immigrant children of indigenous and mixed-race origins is constructed. The starting premise is that interculturality is also an interactive process of communication between individuals of different cultures. The methodology is based on the results of an anthropological study carried out at the Center for Comprehensive Attention to Migrant Children, in Ascension, Chihuahua. Based on observations and interviews, it was found that immigrant children construct interculturality in the classrooms, in the recreation areas, and during the journey to school. Therefore, the conclusion is that they do so in these school spaces, through relationships and meanings, sometimes in dispute, which they establish among themselves and with the teaching staff.

  9. The fuel consumption increase in Ciudad Juarez, Chihuahua

    Directory of Open Access Journals (Sweden)

    Thomas M. Fullerton Jr

    2012-07-01

    Full Text Available This research analyzes short–run gasoline consumption dynamics in Ciudad Juárez, Chihuahua, México. Parameter estimation is carried out using linear transfer function arima analysis. This market is of interest because it is influenced by regional, national, and international economic conditions due to its location on the border with the United States. Explanatory variables that satisfy the significance criterion include the real price of gasoline in Ciudad Juárez, the price of gasoline in Ciudad Juárez relative to that charged across the border in el Paso, Texas, USA, and formal sector employment in Ciudad Juárez. Out–of–sample simulations indicate that the model is relatively accurate for forecasts of to 1 to 24 months into the future.

  10. The Palmottu analogue project

    International Nuclear Information System (INIS)

    Ahonen, L.; Blomqvist, R.; Suksi, J.

    1993-01-01

    The report gives a summary of the results of investigations carried out in 1992 at the Palmottu natural analogue study site, which is a small U-Th mineralization in Nummi-Pusula, southwestern Finland. Additionally, the report includes several separate articles dealing with various aspects of the Palmottu Analogue Project: (1) deep groundwater flow, (2) interpretation of hydraulic connections, (3) characterization of groundwater colloids, (4) uranium mineral-groundwater equilibrium, (5) water-rock interaction and (6) modelling of in situ matrix diffusion. The Palmottu Analogue Project aims at a more profound understanding of radionuclide transport processes in fractured crystalline bedrock. The essential factors controlling transport are groundwater flow and interaction between water and rock. Accordingly, the study includes (1) structural interpretations partly based on geophysical measurements, (2) hydrological studies including hydraulic drill-hole measurements, (3) flow modelling, (4) hydrogeochemical characterization of groundwater, uranium chemistry and colloid chemistry, (5) mineralogical studies, (6) geochemical interpretation and modelling, (7) studies of radionuclide mobilization and retardation including matrix diffusion, and (8) modelling of uranium series data. Palaeohydrogeological aspects, due to the anticipated future glaciation of the Fennoscandian Shield, are of special interest. Quaternary sediments are studied to gain information on post-glacial migration in the overburden. (orig.)

  11. Ground water chemistry and geochemical modeling of water-rock interactions at the Osamu Utsumi mine and the Morro do Ferro analogue study sites, Poços de Caldas, Minas Gerais, Brazil

    Science.gov (United States)

    Nordstrom, D. Kirk; McNutt, R.H.; Puigdomenech, I.; Smellie, John A.T.; Wolf, M.

    1992-01-01

    Surface and ground waters, collected over a period of three years from the Osamu Utsumi uranium mine and the Morro do Ferro thorium/rare-earth element (Th/REE) deposits, were analyzed and interpreted to identify the major hydrogeochemical processes. These results provided information on the current geochemical evolution of ground waters for two study sites within the Poços de Caldas Natural Analogue Project.

  12. Diversity of amphibians and reptiles associated with grasslands of Janos-Casas Grandes, Chihuahua, Mexico (La diversidad de anfibios y reptiles asociada a los pastizales de Janos-Casas Grandes, Chihuahua, Mexico)

    Science.gov (United States)

    Georgina Santos-Barrera; Jesus Pacheco-Rodriguez

    2006-01-01

    Prairie-dog (Cynomys ludovicianus) colonies in northwest Chihuahua, Mexico, have been of great significance not only in initiating protection programs for the species but also in learning about the biological diversity (flora and fauna) of the natural grasslands of Janos-Casas Grandes, Chihuahua. Therefore a study of the herpetological fauna within the prairie-dog...

  13. Comparison of 3D quantitative structure-activity relationship methods: Analysis of the in vitro antimalarial activity of 154 artemisinin analogues by hypothetical active-site lattice and comparative molecular field analysis

    Science.gov (United States)

    Woolfrey, John R.; Avery, Mitchell A.; Doweyko, Arthur M.

    1998-03-01

    Two three-dimensional quantitative structure-activity relationship (3D-QSAR) methods, comparative molecular field analysis (CoMFA) and hypothetical active site lattice (HASL), were compared with respect to the analysis of a training set of 154 artemisinin analogues. Five models were created, including a complete HASL and two trimmed versions, as well as two CoMFA models (leave-one-out standard CoMFA and the guided-region selection protocol). Similar r2 and q2 values were obtained by each method, although some striking differences existed between CoMFA contour maps and the HASL output. Each of the four predictive models exhibited a similar ability to predict the activity of a test set of 23 artemisinin analogues, although some differences were noted as to which compounds were described well by either model.

  14. Mineralogical, chemical, organic and microbial properties of subsurface soil cores from Mars Desert Research Station (Utah, USA): Phyllosilicate and sulfate analogues to Mars mission landing sites

    NARCIS (Netherlands)

    Stoker, C.R.; Clarke, J.; Oliveira Lebre Direito, M.S.; Martin, K.; Zavaleta, J.; Blake, D.; Foing, B.H.

    2011-01-01

    We collected and analysed soil cores from four geologic units surrounding Mars Desert Research Station (MDRS) Utah, USA, including Mancos Shale, Dakota Sandstone, Morrison formation (Brushy Basin member) and Summerville formation. The area is an important geochemical and morphological analogue to

  15. The T wave in the V10 precordial electrocardiographic lead is negative in healthy Chihuahua dogs.

    Science.gov (United States)

    Dijkstra, Marieke; Szatmári, Viktor

    2009-12-01

    The T wave polarity in the V10 precordial electrocardiographic (ECG) lead in Chihuahuas is described as positive in the veterinary literature. The aim of this study was to investigate the polarity of the T wave in the V10 precordial ECG lead in clinically healthy Chihuahuas. Our null hypothesis was that healthy Chihuahuas have a negative T wave in V10. In this prospective study, 67 healthy breeder-owned Chihuahuas were used. A physical examination, 10-lead ECG and an echocardiogram were performed on each dog. No cardio-respiratory abnormalities were revealed in any of the otherwise healthy dogs. Three out of 67 ECGs were of insufficient quality because of baseline artifacts due to movement of the animal. Two other ECGs showed a nearly iso-electric T wave in the V10 lead. The remaining 62 ECGs showed negative T waves in the V10 lead. Right ventricular hypertrophy was excluded with echocardiography in all dogs. In contrast to previous reports, we found that healthy Chihuahuas have negative T wave in the V10 precordial ECG lead.

  16. Patent ductus arteriosus in a family of Chihuahuas.

    Science.gov (United States)

    Bomassi, E; Libermann, S; Bille, C; Rattez, E

    2011-04-01

    This report describes a patent ductus arteriosus (PDA) in four puppies from the same family of Chihuahuas, bred from the same mother and from two different litters. Identification of this congenital anomaly relies on clinical examination, radiography and ultrasonography. Three of these puppies were female, and had a type-1 PDA. A conventional surgical ligation was performed on one of them, whilst the others underwent no treatment. One puppy was male, and presented with a type-4 PDA, requiring euthanasia. Post-mortem examination and histopathological examination of the PDA allowed characterisation of the histological anomalies, which were identical to those described in other breeds. The mother and the two stud dogs were not affected. Even though the mode of transmission has not been fully identified, it is evident that this PDA is hereditary in nature. To the authors' knowledge this is the first description of this congenital cardiopathy in a family of this breed, and in a significant number of first-generation individuals. © 2011 British Small Animal Veterinary Association.

  17. Radioactive mineral samples from the northwest of Chihuahua City, Mexico

    International Nuclear Information System (INIS)

    Reyes C, M.; Montero C, M.E.; Renteria V, M.; Fuentes M, L.; Fuentes C, L.; Herrera P, E.F.; Esparza P, H.; Rodriguez P, A.

    2007-01-01

    The Chihuahua-Sacramento valley is an area of 6 km wide by about 32 km in length, it is located from north to south. In the area, at least two zones exist that may have rocks with radioactive minerals: The Pastorias zone at the SW and the Majalca-San Marcos zone to the NW. The latter, was the object of the present investigation. By studying the geologic conditions and the processes of alteration in the San Marcos deposits, its hydrothermal origin and the different (at least two) alteration stages that has transformed the alkaline rhyolitic rock into per-alkaline were determined, to do more favorable the conditions for the hexavalent uranium minerals deposits. In the mineralogical characterization the following radioactive species were identified: uranofane, meta tyuyamunite and uraninite. These minerals were found also with secondary quartz-feldspar mineralization, with abundant hematization and an advanced process of argillization. The XRD, SEM and optical microscopy analyses of samples were very important for the accomplishment of the present investigation. (Author)

  18. Radioactive mineral samples from the northwest of Chihuahua City, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Reyes C, M.; Montero C, M.E.; Renteria V, M.; Fuentes M, L.; Fuentes C, L.; Herrera P, E.F.; Esparza P, H. [Facultad de Ingenieria, Universidad Autonoma de Chihuahua, Nuevo Campus Universitario s/n, Chihuahua, Mexico y Centro de Investigacion en Materiales Avanzados, Miguel de Cervantes 120, 31109 Chihuahua (Mexico); Rodriguez P, A. [World Wildlife Fund (WWF), Chihuahuan Desert Program, Coronado 1005, 31000 Chihuahua (Mexico)]. e-mail: elena.montero@cimav.edu.mx

    2007-07-01

    The Chihuahua-Sacramento valley is an area of 6 km wide by about 32 km in length, it is located from north to south. In the area, at least two zones exist that may have rocks with radioactive minerals: The Pastorias zone at the SW and the Majalca-San Marcos zone to the NW. The latter, was the object of the present investigation. By studying the geologic conditions and the processes of alteration in the San Marcos deposits, its hydrothermal origin and the different (at least two) alteration stages that has transformed the alkaline rhyolitic rock into per-alkaline were determined, to do more favorable the conditions for the hexavalent uranium minerals deposits. In the mineralogical characterization the following radioactive species were identified: uranofane, meta tyuyamunite and uraninite. These minerals were found also with secondary quartz-feldspar mineralization, with abundant hematization and an advanced process of argillization. The XRD, SEM and optical microscopy analyses of samples were very important for the accomplishment of the present investigation. (Author)

  19. Sails: a new gypsum speleothem from Naica, Chihuahua, Mexico

    Directory of Open Access Journals (Sweden)

    Forti Paolo

    2007-01-01

    Full Text Available The caves of Naica (Chihuahua, Mexico are perhaps the most famous mine caves of the world due to the presence of giganticgypsum crystals. Nevertheless, very little research has been carried out on this karst area until now. A multidisciplinary investigationstarted in 2006 with the aim not only to define the genesis and the age of the Naica gypsum crystals, but also on other scientificaspects of these caves.This paper describes a completely new type of gypsum speleothem: the “sails”, observed only inside the Cueva de las Velas, one ofthe caves of the Naica system. This speleothem consists of extremely thin, elongated skeleton crystals that have grown epitaxiallyonly on the tips of the gypsum crystals pointing upward. The genesis of sails is strictly related to the environmental conditions setup inside the cave just after the artificial lowering of the groundwater by mine dewatering (less than 20 yr ago. In a few years sail speleothems will disappear entirely and therefore this study is fundamental to preserve at least the memory of them.

  20. Experience in the transport and disposal of uranium mill tailings from Aldama City to Sierra Pena Blanca in Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Ruiz, M.; Molina, G.; Angeles C, A.; Cruz G, S.; Lizacano C, D.; Reyes, J.; Rojas, V.

    1996-01-01

    In the process of decontamination, transport and disposal of uranium mill tailings, in the state of Chihuahua, Mexico, was necessary the multidisciplinary and multi institutional task to select mainly the site for the final disposal. The uranium mill tailings content Ra-226 which half live time is 1600 years, therefore the site should be adequately stable, a remote place of population, and which containment will survive for thousand of years. The decontamination of site where the uranium mill tailings were 25 years ago, required the application of norms from regulator organism. For the transport of uranium mill tailings was necessary that the vehicles had devices to reduce the dispersion of material in the road. The selection of the site was product of balance between the cost of transport and the final disposal. To typify the site, studies of hydrology, meteorology, ecology, geology and seismology were performed. On the other hand, the decision to locate the deposit in the site was due to dispersion of material by the rain, wind and bowls. (authors). 3 refs., 1 fig., 1 tab

  1. Four centuries of reconstructed hydroclimatic variability for Northwestern Chihuahua, Mexico, based on tree rings

    Directory of Open Access Journals (Sweden)

    José Villanueva Díaz

    2015-03-01

    Full Text Available A Douglas-fir chronology with a length of 409 years (1600-2008 was developed for northwestern Chihuahua in Mesa de las Guacamayas, a “Natural Protected Area” known as an important nesting habitat for the thickbilled parrot (Rhynchopsitta pachyrhyncha an endangered neotropical bird. Increment cores and cross-sections from selected Douglas-fir trees (Pseudotsuga menziesii in a mixed conifer forest were obtained with an increment borer and a chain-saw. Standard dendrochronological techniques were used to process and date each one of the rings to their exact year of formation. The quality of dating of the measured series was analyzed with the COFECHA program, while biological trends not related to climate (age differences, stem-size increases, and disturbances were removed by standardization procedures in the ARSTAN program. Tree ring series of earlywood, latewood and total ring width were developed for the last four centuries. The total ring-width chronology was significantly associated (r>0.40, p=0.000 with nearby chronologies, particularly those located <200 km apart along the western slopes of the Sierra Madre Occidental (SMO observing correlations as high as 0.69 (p<0.001. Association between chronologies decreased for those sites in the state of Durango along the SMO but separated more than 200 km in straight line and also for sites in nearby borderline in the USA side. The similar climatic response among distant chronologies implies the influence of common atmospheric circulatory patterns affecting a large portion of land simultaneously. ENSO is one of the most important factors in determining inter-annual and multiannual hydroclimatic variability in northern Mexico, increasing winter-spring precipitation in its warm phase and causing extreme droughts in its cold phase.

  2. Neuronal ceroid lipofuscinosis associated with an MFSD8 mutation in Chihuahuas.

    Science.gov (United States)

    Ashwini, Akanksha; D'Angelo, Antonio; Yamato, Osamu; Giordano, Cristina; Cagnotti, Giulia; Harcourt-Brown, Tom; Mhlanga-Mutangadura, Tendai; Guo, Juyuan; Johnson, Gary S; Katz, Martin L

    2016-08-01

    The neuronal ceroid lipofuscinoses (NCLs) are hereditary neurodegenerative disorders characterized by progressive declines in neurological functions, seizures, and premature death. NCLs result from mutations in at least 13 different genes. Canine versions of the NCLs can serve as important models in developing effective therapeutic interventions for these diseases. NCLs have been described in a number of dog breeds, including Chihuahuas. Studies were undertaken to further characterize the pathology of Chihuahua NCL and to verify its molecular genetic basis. Four unrelated client owned Chihuahuas from Japan, Italy and England that exhibited progressive neurological signs consistent with a diagnosis of NCL underwent neurological examinations. Brain and in some cases also retinal and heart tissues were examined postmortem for the presence of lysosomal storage bodies characteristic of NCL. The affected dogs exhibited massive accumulation of autofluorescent lysosomal storage bodies in the brain, retina and heart accompanied by brain atrophy and retinal degeneration. The dogs were screened for known canine NCL mutations previously reported in a variety of dog breeds. All 4 dogs were homozygous for the MFSD8 single base pair deletion (MFSD8:c.843delT) previously associated with NCL in a Chinese Crested dog and in 2 affected littermate Chihuahuas from Scotland. The dogs were all homozygous for the normal alleles at the other genetic loci known to cause different forms of canine NCL. The MFSD8:c.843delT mutation was not present in 57 Chihuahuas that were either clinically normal or suffered from unrelated diseases or in 1761 unaffected dogs representing 186 other breeds. Based on these data it is almost certain that the MFSD8:c.843delT mutation is the cause of NCL in Chihuahuas. Because the disorder occurred in widely separated geographic locations or in unrelated dogs from the same country, it is likely that the mutant allele is widespread among Chihuahuas. Genetic testing

  3. Boer Colonization in Chihuahua and the American Southwest, 1903-1917

    Directory of Open Access Journals (Sweden)

    Lawrence Douglas Taylor Hansen

    2002-10-01

    Full Text Available The colonizing efforts of some groups of Boer exiled from Southafrica in Chihuahua and the American  southwest, a few years after the second anglo-boer war from 1899 to 1902, are analysed in this article. The study focuses, mainly, on the circumstances that originated this proyect  and the reasons  for the nonefulfillment of the colony settled in Chihuahua, which provoked the dissemination of most of the settlers into other regions.  On a comparative basis, two more  proyects  are analysed: the establishment of foreign Mormon and Mennonite settlers, who shared some of the Boer migrant characteristics, in Mexico.

  4. y gestión de la política regional. El caso de Chihuahua

    Directory of Open Access Journals (Sweden)

    Luis Enrique Gutiérrez Casas

    2007-01-01

    Full Text Available This essay describes the regional development potential model and proposes a reviewed version of Biehl approach. Based on this model it is introduced a classification system capable of characterizing different regional contexts and anticipate public policies for specific territorial problems. The case of study is the mexican northern state of Chihuahua. The findings of this study validates the model as an analytical tool—non-substitute but complementary to the set of models and instruments used by regional economics—, and gives practical information in order to planning development policies for the municipalities of Chihuahua.

  5. Design, Synthesis, and in Vitro Pharmacology of New Radiolabeled γ-Hydroxybutyric Acid Analogues Including Photolabile Analogues with Irreversible Binding to the High-Affinity γ-Hydroxybutyric Acid Binding Sites

    DEFF Research Database (Denmark)

    Sabbatini, Paola; Wellendorph, Petrine; Høg, Signe

    2010-01-01

    γ-Hydroxybutyric acid (GHB) is a psychotropic compound endogenous to the brain. Despite its potential physiological significance, the complete molecular mechanisms of action remain unexplained. To facilitate the isolation and identification of the high-affinity GHB binding site, we herein report ...

  6. Analogue MIMO Detection

    Directory of Open Access Journals (Sweden)

    McNamara Darren

    2006-01-01

    Full Text Available In this contribution we propose an analogue receiver that can perform turbo detection in MIMO systems. We present the case for a receiver that is built from nonlinear analogue devices, which perform detection in a "free-flow" network (no notion of iterations. This contribution can be viewed as an extension of analogue turbo decoder concepts to include MIMO detection. These first analogue implementations report reductions of few orders of magnitude in the number of required transistors and in consumed energy, and the same order of improvement in processing speed. It is anticipated that such analogue MIMO decoder could bring about the same advantages, when compared to traditional digital implementations.

  7. Dose by {sup 222} Rn in houses of the Chihuahua city; Dosis por {sup 222} Rn en casas-habitacion de la ciudad de Chihuahua

    Energy Technology Data Exchange (ETDEWEB)

    Colmenero S, L.H.; Talamantes F, C. [ITCH II, Ave. de las Industrias 11101, Chihuahua (Mexico); Villalba, M.L. [UACH, Facultad de Ingenieria, Chihuahua (Mexico); Dobson, P.F. [Laboratorio Nacional Lawrence Berkeley, California (United States); Ortalejo M, B. [UACH, Facultad de Enfermeria y Nutriologia, Chihuahua (Mexico)]. e-mail: luis.colmenero@cimav.edu.mx

    2007-07-01

    Full text: The dose equivalent that the population of the Chihuahua city receives due to the radon in air that joined to values of uranium, thorium and potassium due to the floor and radon in water was determined, they give values very above the international and national norms. The state of Chihuahua contains near 56 locations distributed by the whole state. The city of Chihuahua, capital of the state, is surrounded of rocks with great content of uranium, for what their floor also contains to the {sup 226} Ra that generates to the {sup 222} Rn. The construction of the housings of the city of Chihuahua is mainly of brick, block and adobe; the material to elaborate them is take from the rocks and floor of the surroundings, this makes that the radon is presented in a great quantity of houses of this city. As the floor and water they also contain those natural radionuclides, the total dose equivalent that the inhabitants receive is bigger to other cities of the country. Diverse international organizations dedicated to the radioactivity, indicate that the level of the {sup 222} Rn should not surpass the 148 Bq/m{sup 3}, since this gas produces lung cancer. The state of Chihuahua has an index of deaths on the average by lung cancer of double the national average, the capital of the state also has a high index. The radon concentration in a house depends on the construction material with which was made, as well as of the existent climatic conditions. During the day, this concentration depends mainly on the interior temperature, so during the night and dawn increases the radon concentration. The radon is the biggest source of radioactive dose received by the human being and it can generate a problem of public health if the concentration is high during enough time, for what the city of Chihuahua has the geologic and climatic characteristics to have it. This study was carried out in 50 house-room of the city of Chihuahua. Built houses with brick, block and adobe were

  8. Natural radioactivity in soils of the main cities of the State of Chihuahua; Radiactividad natural en suelos de las principales ciudades del Estado de Chihuahua

    Energy Technology Data Exchange (ETDEWEB)

    Colmenero S, L.; Montero C, M.E.; Villalba, L. [CIMAV, Av. Miguel de Cervantes Saavedra 120, 31109 Chihuahua (Mexico)]. e-mail: luis.colmenero@cimav.edu.mx

    2003-07-01

    The state of Chihuahua counts with at least 56 uranium zones or of minerals associated to this, being Pena Blanca the greatest and more important deposit of the country. Some of the main cities of the state are near to these deposits, as Aldama and Chihuahua. Its were took samples of soil of 11 cities of the state to determine the natural activity of radionuclides. It was determined the specific activity attributable to the parents of the series of {sup 238} U, {sup 232} Th, and of the {sup 40} K isotopes, as well as effective dose rate H{sub E} in the soil samples. It was used the high resolution gamma spectrometry of a high purity Ge detector in the laboratory of Environmental Radiological Surveillance of the CIMAV. The measure of the activity of the uranium series carries out by means of the lines of 351 KeV of the {sup 214} Pb and of 609 keV of the {sup 214} Bi, while the thorium series it was deduced of the lines of 238 keV of the {sup 212} Pb and of 912 keV of the {sup 228} Ac. Its were carried out copies and replies for the quality control. Its were found high values of specific activity of some radionuclides, in the near cities to uranium deposits like Aldama and Chihuahua. For the cities that are not near to deposits, as Ciudad Juarez and Ojinaga, the found values were normal. Also the effective dose rate was high for the near cities to deposits like Aldama, Bocoyna, Chihuahua, Jimenez and Nuevo Casas Grandes, it is also necessary to determine, the radon in air levels and of radionuclides in consumption water to obtain the dose that the population of those populations receives. (Author)

  9. Heterogeneous Seepage at the Nopal I Uranium Mine, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Dobson, Patrick; Dobson, Patrick F.; Cook, Paul J.; Ghezzehei, Teamrat; Rodriguez, J. Alfredo; Garza, Rodrigo de la

    2008-01-01

    The primary objective of this analogue study is to evaluate flow and transport processes of relevance to the proposed Yucca Mountain repository. Seepage data obtained from this study will be used to constrain flow and transport models being developed for the Nopal I system

  10. Uranium series isotopes concentration in sediments at San Marcos and Luis L. Leon reservoirs, Chihuahua, Mexico

    Science.gov (United States)

    Méndez-García, C.; Renteria-Villalobos, M.; García-Tenorio, R.; Montero-Cabrera, M. E.

    2014-07-01

    Spatial and temporal distribution of the radioisotopes concentrations were determined in sediments near the surface and core samples extracted from two reservoirs located in an arid region close to Chihuahua City, Mexico. At San Marcos reservoir one core was studied, while from Luis L. Leon reservoir one core from the entrance and another one close to the wall were investigated. 232Th-series, 238U-series, 40K and 137Cs activity concentrations (AC, Bq kg-1) were determined by gamma spectrometry with a high purity Ge detector. 238U and 234U ACs were obtained by liquid scintillation and alpha spectrometry with a surface barrier detector. Dating of core sediments was performed applying CRS method to 210Pb activities. Results were verified by 137Cs AC. Resulting activity concentrations were compared among corresponding surface and core sediments. High 238U-series AC values were found in sediments from San Marcos reservoir, because this site is located close to the Victorino uranium deposit. Low AC values found in Luis L. Leon reservoir suggest that the uranium present in the source of the Sacramento - Chuviscar Rivers is not transported up to the Conchos River. Activity ratios (AR) 234U/overflow="scroll">238U and 238U/overflow="scroll">226Ra in sediments have values between 0.9-1.2, showing a behavior close to radioactive equilibrium in the entire basin. 232Th/overflow="scroll">238U, 228Ra/overflow="scroll">226Ra ARs are witnesses of the different geological origin of sediments from San Marcos and Luis L. Leon reservoirs.

  11. Uranium series isotopes concentration in sediments at San Marcos and Luis L. Leon reservoirs, Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Méndez-García, C.; Montero-Cabrera, M. E., E-mail: elena.montero@cimav.edu.mx [Centro de Investigación en Materiales Avanzados, CIMAV, Miguel de Cervantes 120, 31109, Chihuahua, Chihuahua (Mexico); Renteria-Villalobos, M. [Facultad de Zootecnia y Ecología Universidad Autónoma de Chihuahua, Periferico Francisco R. Almada Km 1, 31410, Chihuahua (Mexico); García-Tenorio, R. [Applied Nuclear Physics Group, University of Seville, ETS Arquitectura, Avda. Reina Mercedes s/n, 41012 Seville (Spain)

    2008-01-01

    Spatial and temporal distribution of the radioisotopes concentrations were determined in sediments near the surface and core samples extracted from two reservoirs located in an arid region close to Chihuahua City, Mexico. At San Marcos reservoir one core was studied, while from Luis L. Leon reservoir one core from the entrance and another one close to the wall were investigated. ²³²Th-series, ²³⁸U-series, ⁴⁰K and ¹³⁷Cs activity concentrations (AC, Bq kg⁻¹) were determined by gamma spectrometry with a high purity Ge detector. ²³⁸U and ²³⁴U ACs were obtained by liquid scintillation and alpha spectrometry with a surface barrier detector. Dating of core sediments was performed applying CRS method to ²¹⁰Pb activities. Results were verified by ¹³⁷Cs AC. Resulting activity concentrations were compared among corresponding surface and core sediments. High ²³⁸U-series AC values were found in sediments from San Marcos reservoir, because this site is located close to the Victorino uranium deposit. Low AC values found in Luis L. Leon reservoir suggest that the uranium present in the source of the Sacramento – Chuviscar Rivers is not transported up to the Conchos River. Activity ratios (AR) ²³⁴U/²³⁸U and ²³⁸U/²²⁶Ra in sediments have values between 0.9–1.2, showing a behavior close to radioactive equilibrium in the entire basin. ²³²Th/²³⁸U, ²²⁸Ra/²²⁶Ra ARs are witnesses of the different geological origin of sediments from San Marcos and Luis L. Leon reservoirs.

  12. Uranium series isotopes concentration in sediments at San Marcos and Luis L. Leon reservoirs, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Méndez-García, C.; Montero-Cabrera, M. E.; Renteria-Villalobos, M.; García-Tenorio, R.

    2014-01-01

    Spatial and temporal distribution of the radioisotopes concentrations were determined in sediments near the surface and core samples extracted from two reservoirs located in an arid region close to Chihuahua City, Mexico. At San Marcos reservoir one core was studied, while from Luis L. Leon reservoir one core from the entrance and another one close to the wall were investigated. 232 Th-series, 238 U-series, 40 K and 137 Cs activity concentrations (AC, Bq kg −1 ) were determined by gamma spectrometry with a high purity Ge detector. 238 U and 234 U ACs were obtained by liquid scintillation and alpha spectrometry with a surface barrier detector. Dating of core sediments was performed applying CRS method to 210 Pb activities. Results were verified by 137 Cs AC. Resulting activity concentrations were compared among corresponding surface and core sediments. High 238 U-series AC values were found in sediments from San Marcos reservoir, because this site is located close to the Victorino uranium deposit. Low AC values found in Luis L. Leon reservoir suggest that the uranium present in the source of the Sacramento – Chuviscar Rivers is not transported up to the Conchos River. Activity ratios (AR) 234 U/ 238 U and 238 U/ 226 Ra in sediments have values between 0.9–1.2, showing a behavior close to radioactive equilibrium in the entire basin. 232 Th/ 238 U, 228 Ra/ 226 Ra ARs are witnesses of the different geological origin of sediments from San Marcos and Luis L. Leon reservoirs

  13. Characterization of source rocks and groundwater radioactivity at the Chihuahua valley

    Energy Technology Data Exchange (ETDEWEB)

    Renteria V, M.; Montero C, M.E.; Reyes C, M.; Herrera P, E.F.; Valenzuela H, M. [Centro de lnvestigacion en Materiales Avanzados, Miguel de Cervantes 120, 31109 Chihuahua, (Mexico); Rodriguez P, A. [World Wildlife Fund (WWF), Chihuahuan Desert Program, Coronado 1005, 31000 Chihuahua (Mexico); Manjon C, G.; Garcia T, R. [Universidad de Sevilla, Departamento de Fisica Aplicada 11, ETS Arquitectura, Av. Reina Mercedes 2, 41012 Sevilla, (Spain); Crespo, T. [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas (CIEMAT), Av. Complutense 22, 28040 Madrid, (Spain)]. e-mail: elena.montero@cimav.edu.mx

    2007-07-01

    As part of a scientific research project about alpha radioactivity in groundwater for human consumption at the Chihuahua City, the characterization of rock sources of radioactivity around de Chihuahua valley was developed. The radioactivity of groundwater and sediments was determined, too. The radioactivity of uranium- and thorium- series isotopes contained in rocks was obtained by high resolution gamma-ray spectroscopy. Some representative values are 50 Bq/kg for the mean value of Bi-214 activity, and 121.5 Bq/kg for the highest value at West of the city. The activity of sediments, extracted during wells perforation, was determined using a Nal(TI) detector. A non-reported before uranium ore was localized at the San Marcos range formation. Its outcrops are inside the Chihuahua-Sacramento valley basin and its activity characterization was performed. Unusually high specific uranium activities, determined by alpha spectrometry, were obtained in water, plants, sediments and fish extracted at locations close to outcrops of uranium minerals. The activity of water of the San Marcos dam reached 7.7 Bq/L. The activity of fish, trapped at San Marcos dam, is 0.99 Bq/kg. Conclusions about the contamination of groundwater at North of Chihuahua City were obtained. (Author)

  14. Characterization of source rocks and groundwater radioactivity at the Chihuahua valley

    International Nuclear Information System (INIS)

    Renteria V, M.; Montero C, M.E.; Reyes C, M.; Herrera P, E.F.; Valenzuela H, M.; Rodriguez P, A.; Manjon C, G.; Garcia T, R.; Crespo, T.

    2007-01-01

    As part of a scientific research project about alpha radioactivity in groundwater for human consumption at the Chihuahua City, the characterization of rock sources of radioactivity around de Chihuahua valley was developed. The radioactivity of groundwater and sediments was determined, too. The radioactivity of uranium- and thorium- series isotopes contained in rocks was obtained by high resolution gamma-ray spectroscopy. Some representative values are 50 Bq/kg for the mean value of Bi-214 activity, and 121.5 Bq/kg for the highest value at West of the city. The activity of sediments, extracted during wells perforation, was determined using a Nal(TI) detector. A non-reported before uranium ore was localized at the San Marcos range formation. Its outcrops are inside the Chihuahua-Sacramento valley basin and its activity characterization was performed. Unusually high specific uranium activities, determined by alpha spectrometry, were obtained in water, plants, sediments and fish extracted at locations close to outcrops of uranium minerals. The activity of water of the San Marcos dam reached 7.7 Bq/L. The activity of fish, trapped at San Marcos dam, is 0.99 Bq/kg. Conclusions about the contamination of groundwater at North of Chihuahua City were obtained. (Author)

  15. Democratic Leadership in Middle Schools of Chihuahua Mexico: Improving Middle Schools through Democracy

    Science.gov (United States)

    Delgado, Manuel Lopez

    2014-01-01

    The purpose of this study was to analyse the effects of the implementation of a democratic approach to lead and manage middle schools in Chihuahua, Mexico. This research was based on a Likert questionnaire and semistructured interviews to explore the level of involvement of students, teachers, and parents in schools participating in a programme…

  16. Use of deuterium and oxygen-18 in hydrological problems at Delicias Valley, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Castillo C, R.; Morales, P.; Cortes, A.

    1983-01-01

    An initial study using stable isotopes at Delicias Valley, Chihuahua, is presented, where we found an aquifer with two kinds of waters, one of recent infiltration (highly fractionated) and another of more depleted isotope concentration representing precipitation before the construction of the dam and distribution channels. (author)

  17. Identification of ischemia-regulated phosphorylation sites in connexin43: A possible target for the antiarrhythmic peptide analogue rotigaptide (ZP123)

    DEFF Research Database (Denmark)

    Axelsen, Lene Nygaard; Stahlhut, Martin; Mohammed, Shabaz

    2006-01-01

    Previous studies suggest that dephosphorylation of connexin43 (Cx43) is related to uncoupling of gap junction communication, which plays an important role in the genesis of ischemia-induced ventricular tachycardia. We studied changes in Cx43 phosphorylation during global ischemia in the absence...... and presence of the antiarrhythmic peptide analogue rotigaptide (formerly known as ZP123). Phosphorylation analysis was performed on Cx43 purified from isolated perfused rat hearts using matrix-assisted laser desorption/ionization mass spectrometry and liquid chromatography electrospray ionization tandem mass...... of ischemia, the critical time interval where gap junction uncoupling occurs, Ser297 and Ser368 also became fully dephosphorylated. During the same time period, all untreated hearts developed asystole. Treatment with rotigaptide significantly increased the time to ischemia-induced asystole and suppressed...

  18. Mineralogical, chemical, organic and microbial properties of subsurface soil cores from Mars Desert Research Station (Utah, USA): Phyllosilicate and sulfate analogues to Mars mission landing sites

    Science.gov (United States)

    Stoker, Carol R.; Clarke, Jonathan; Direito, Susana O. L.; Blake, David; Martin, Kevin R.; Zavaleta, Jhony; Foing, Bernard

    2011-07-01

    We collected and analysed soil cores from four geologic units surrounding Mars Desert Research Station (MDRS) Utah, USA, including Mancos Shale, Dakota Sandstone, Morrison formation (Brushy Basin member) and Summerville formation. The area is an important geochemical and morphological analogue to terrains on Mars. Soils were analysed for mineralogy by a Terra X-ray diffractometer (XRD), a field version of the CheMin instrument on the Mars Science Laboratory (MSL) mission (2012 landing). Soluble ion chemistry, total organic content and identity and distribution of microbial populations were also determined. The Terra data reveal that Mancos and Morrison soils are rich in phyllosilicates similar to those observed on Mars from orbital measurements (montmorillonite, nontronite and illite). Evaporite minerals observed include gypsum, thenardite, polyhalite and calcite. Soil chemical analysis shows sulfate the dominant anion in all soils and SO4>>CO3, as on Mars. The cation pattern Na>Ca>Mg is seen in all soils except for the Summerville where Ca>Na. In all soils, SO4 correlates with Na, suggesting sodium sulfates are the dominant phase. Oxidizable organics are low in all soils and range from a high of 0.7% in the Mancos samples to undetectable at a detection limit of 0.1% in the Morrison soils. Minerals rich in chromium and vanadium were identified in Morrison soils that result from diagenetic replacement of organic compounds. Depositional environment, geologic history and mineralogy all affect the ability to preserve and detect organic compounds. Subsurface biosphere populations were revealed to contain organisms from all three domains (Archaea, Bacteria and Eukarya) with cell density between 3.0×106 and 1.8×107 cells ml-1 at the deepest depth. These measurements are analogous to data that could be obtained on future robotic or human Mars missions and results are relevant to the MSL mission that will investigate phyllosilicates on Mars.

  19. Persistent environmental pollutants in eggs of aplomado falcons from Northern Chihuahua, Mexico, and South Texas, USA

    Science.gov (United States)

    Mora, M.A.; Montoya, A.B.; Lee, M.C.; Macias-Duarte, Alberto; Rodriguez-Salazar, R.; Juergens, P.W.; Lafon-Terrazas, A.

    2008-01-01

    The northern aplomado falcon (Falco femoralis septentrionalis) disappeared from south Texas in the 1940s. Due to great success in the release of captive-reared aplomado falcons in south Texas, there are currently more than 40 established nesting pairs in the region. Addled eggs from aplomado falcons nesting in northern Chihuahua and south Texas were analyzed to determine organochlorine (OC) and inorganic element contaminant burdens and their potential association with egg failures and effects on reproduction. Among the OCs, DDE [1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene] was present at the highest concentrations (range 262-21487??ng/g wet weight) followed by polychlorinated biphenyls (PCBs, range 88-3274??ng/g ww). DDE was greater (P = 0.03) in eggs from El Sueco (Chihuahua, Mexico) than in those from Matagorda Island (Texas, USA). DDE concentrations in eggs of aplomado falcons from El Sueco were elevated; however, reproductive success in the two Chihuahuan populations did not seem to be affected by DDE. DDE and metals in potential avian prey of the aplomado falcon from Matagorda Island were very low and below levels in the diet at which some negative effects might be expected. Except for mercury (Hg), metal concentrations in eggs were fairly low and were not different among locations in Chihuahua and south Texas. Hg was somewhat elevated and was greater (P Chihuahua locations. Periodic monitoring of Hg concentrations in addled eggs of aplomado falcons in south Texas is recommended to continue evaluating potential negative effects on their recovery. ?? 2007 Elsevier Ltd. All rights reserved.

  20. Natural radioactivity in soils of the main cities of the State of Chihuahua

    International Nuclear Information System (INIS)

    Colmenero S, L.; Montero C, M.E.; Villalba, L.

    2003-01-01

    The state of Chihuahua counts with at least 56 uranium zones or of minerals associated to this, being Pena Blanca the greatest and more important deposit of the country. Some of the main cities of the state are near to these deposits, as Aldama and Chihuahua. Its were took samples of soil of 11 cities of the state to determine the natural activity of radionuclides. It was determined the specific activity attributable to the parents of the series of 238 U, 232 Th, and of the 40 K isotopes, as well as effective dose rate H E in the soil samples. It was used the high resolution gamma spectrometry of a high purity Ge detector in the laboratory of Environmental Radiological Surveillance of the CIMAV. The measure of the activity of the uranium series carries out by means of the lines of 351 KeV of the 214 Pb and of 609 keV of the 214 Bi, while the thorium series it was deduced of the lines of 238 keV of the 212 Pb and of 912 keV of the 228 Ac. Its were carried out copies and replies for the quality control. Its were found high values of specific activity of some radionuclides, in the near cities to uranium deposits like Aldama and Chihuahua. For the cities that are not near to deposits, as Ciudad Juarez and Ojinaga, the found values were normal. Also the effective dose rate was high for the near cities to deposits like Aldama, Bocoyna, Chihuahua, Jimenez and Nuevo Casas Grandes, it is also necessary to determine, the radon in air levels and of radionuclides in consumption water to obtain the dose that the population of those populations receives. (Author)

  1. Seasonal characterization of municipal solid waste (MSW) in the city of Chihuahua, Mexico.

    Science.gov (United States)

    Gómez, Guadalupe; Meneses, Montserrat; Ballinas, Lourdes; Castells, Francesc

    2009-07-01

    Management of municipal solid waste (MSW) has become a significant environmental problem, especially in fast-growing cities. The amount of waste generated increases each year and this makes it difficult to create solutions which due to the increase in waste generation year after year and having to identify a solution that will have minimum impact on the environment. To determine the most sustainable waste management strategy for Chihuahua, it is first necessary to identify the nature and composition of the city's urban waste. The MSW composition varied considerably depending on many factors, the time of year is one of them. Therefore, as part of our attempt to implement an integral waste management system in the city of Chihuahua, we conducted a study of the characteristics of MSW composition for the different seasons. This paper analyzes and compares the findings of the study of the characterization and the generation of solid waste from households at three different socio-economic levels in the city over three periods (April and August, 2006 and January, 2007). The average weight of waste generated in Chihuahua, taking into account all three seasons, was 0.592 kg capita(-1) day(-1). Our results show that the lowest income groups generated the least amount of waste. We also found that less waste was generated during the winter season. The breakdown for the composition of the waste shows that organic waste accounts for the largest proportion (45%), followed by paper (17%) and others (16%).

  2. Seasonal characterization of municipal solid waste (MSW) in the city of Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Gomez, Guadalupe; Meneses, Montserrat; Ballinas, Lourdes; Castells, Francesc

    2009-01-01

    Management of municipal solid waste (MSW) has become a significant environmental problem, especially in fast-growing cities. The amount of waste generated increases each year and this makes it difficult to create solutions which due to the increase in waste generation year after year and having to identify a solution that will have minimum impact on the environment. To determine the most sustainable waste management strategy for Chihuahua, it is first necessary to identify the nature and composition of the city's urban waste. The MSW composition varied considerably depending on many factors, the time of year is one of them. Therefore, as part of our attempt to implement an integral waste management system in the city of Chihuahua, we conducted a study of the characteristics of MSW composition for the different seasons. This paper analyzes and compares the findings of the study of the characterization and the generation of solid waste from households at three different socio-economic levels in the city over three periods (April and August, 2006 and January, 2007). The average weight of waste generated in Chihuahua, taking into account all three seasons, was 0.592 kg capita -1 day -1 . Our results show that the lowest income groups generated the least amount of waste. We also found that less waste was generated during the winter season. The breakdown for the composition of the waste shows that organic waste accounts for the largest proportion (45%), followed by paper (17%) and others (16%).

  3. Analogue circuits simulation

    Energy Technology Data Exchange (ETDEWEB)

    Mendo, C

    1988-09-01

    Most analogue simulators have evolved from SPICE. The history and description of SPICE-like simulators are given. From a mathematical formulation of the electronic circuit the following analysis are possible: DC, AC, transient, noise, distortion, Worst Case and Statistical.

  4. Aqueous extracts of a Mars analogue regolith that mimics the Phoenix landing site do not inhibit spore germination or growth of model spacecraft contaminants Bacillus subtilis 168 and Bacillus pumilus SAFR-032

    Science.gov (United States)

    Nicholson, Wayne L.; McCoy, Lashelle E.; Kerney, Krystal R.; Ming, Douglas W.; Golden, D. C.; Schuerger, Andrew C.

    2012-08-01

    Because Mars is a primary target for life detection and habitability assessment missions, its exploration is also by necessity a Planetary Protection issue. The recent finding of significant levels of perchlorate (ClO4-) in regolith sampled from the Phoenix landing site raises the question of its potential biotoxicity to putative indigenous martian life, microbial forward contaminants from Earth, or future human visitors. To address this issue, an analogue regolith was constructed based on regolith chemistry data from the Phoenix landing site. A Mars Aqueous Regolith Extract (MARE) was prepared from the Phoenix analogue regolith and analyzed by ion chromatography. The MARE contained (mg/L) the cations Na+ (1411 ± 181), Mg2+ (1051 ± 160), Ca2+ (832 ± 125), and K+ (261 ± 29), and the anions SO42-(5911±993), ClO4-(5316±1767), Cl(171±25) and F- (2.0 ± 0.4). Nitrogen-containing species NO3-(773±113) and NO2-(6.9±2.3) were also present as a result of regolith preparation procedures, but their relevance to Mars is at present unknown. The MARE was tested for potential toxic effects on two model spacecraft contaminants, the spore-forming bacteria Bacillus subtilis strain 168 and Bacillus pumilus strain SAFR-032. In B. subtilis, spore germination and initial vegetative growth (up to ˜5 h) was not inhibited in a rich complex medium prepared with the MARE, but growth after 5 h was significantly suppressed in medium prepared using the MARE. Both B. subtilis and B. pumilus exhibited significantly higher rates of spore germination and growth in the MARE vs. DW with no additions (likely due to endogenous spore nutrients), but germination and growth was further stimulated by addition of glucose and a combination of buffered inorganic salts (K2HPO4, KH2PO4, (NH4)2SO4, and MgSO4). The data indicate that the aqueous environment in the regolith from the Phoenix landing site containing high levels of perchlorate does not pose a significant barrier to growth of putative

  5. Geomorphological and hydrogeological features of the Pocos de Caldas caldera and the Osamu Utsumi mine and Morro do Ferro analogue study sites, Brazil

    International Nuclear Information System (INIS)

    Holmes, D.S.; Noy, D.J.; Pitty, A.E.

    1990-01-01

    The Osamu Utsumi mine and Morro do Ferro study sites lie within the Pocos de Caldas plateau which is roughly circular in outline with a diameter of 35 km and an area of approximately 800 km 2 . Its general altitude lies between 1300 and 1600 m. The plateau is the eroded form of a caldera which initially intruded some 80 million years ago. Geomorphologically, both sites occupy watershed areas adjacent to small streams in the centre of the plateau. The climate of the area has a marked wet season from November to April and is dry the rest of the year. The streams are ephemeral in their upper reaches, tending to dry up in the dry season as they are fed by a declining base flow. In the wet season they exhibit flash floods fed by high-intensity rainfall causing overland flow. The wet season also provides recharge to the groundwater. Natural slopes are steep and the original vegetaion was thin forest cover which is now restricted to the valley bottoms; usable slopes have poor quality grass cover used for cattle grazing. The plateau is a stable feature and its surface has been eroding at an average rate of 12 m per million years over a period of 50 million years. (author) 21 figs., 47 refs

  6. The Palmottu analogue project: overview for 1993

    International Nuclear Information System (INIS)

    Ruskeeniemi, T.; Blomqvist, R.; Suksi, J.; Niini, H.

    1994-01-01

    This article gives a summary of the activities carried out within the Palmottu analogue project in 1993. It consists of (1) an introductory part, followed by (2) a geological description of the site, and (3)an up-to-date summary of the results of the project. (orig.) (33 refs., 6 figs.)

  7. Geomorphological and hydrogeological features of the Pocos de Caldas caldera and the Osamu Utsumi mine and Morro do Ferro analogue study sites, Brazil

    International Nuclear Information System (INIS)

    Holmes, D.C.; Pitty, A.E.; Noy, D.J.

    1990-01-01

    The Osamu Utsumi mine and Morro do Ferro study sites lie within the Pocos de Caldas plateau which is roughly circular in outline with a diameter of 35 km and an area of approximately 800 km 2 . Its general altitude lies between 1300 and 1600 m. The plateau is the eroded form of a caldera which was initially intruded some 80 million years ago. Geomorphologically, both sites occupy watershed areas adjacent to small streams in the centre of the plateau. The climate of the area has a market wet season from November to April and is dry the rest of the year. The streams are ephemeral in their upper reaches, tending to dry up in the dry season as they are fed by a declining base flow. In the wet season they exhibit flash flood fed by high-intensity rainfall causing overland flow. The wet season also provides recharge to the groundwater. Natural slopes are steep and the original vegetation was thin forest cover which is now restricted to the valley bottoms; usable slopes have poor quality grass cover used for cattle grazing. The plateau is a stable feature and its surface has been eroding at an average rate of 12 m per million years over a period of 50 million years. The mine geology is dominantly volcanic to subvolcanic phonolites that have been hydrothermally altered. Fracturing of the rock is extensive. Downward diffusion of oxygen in groundwaters during deep weathering has produced a distinct redox zone seen as a colour change from green/grey to brown/yellow. Morro do Ferro has a more weathered version (laterite/clay) of the same geology penetrated by magnetite breccia dykes. Whilst the area surrounding Morro do Ferro remains untouched, that around the mine has been seriously disturbed by mining activity which has penetrated the water-table. The existing mine has modified groundwater flow patterns and disturbed the movement of oxidising and reducing waters. (au) (47 refs.)

  8. Natural radioactivity in groundwater and estimates of committed effective dose due to water ingestion in the state of Chihuahua (Mexico)

    International Nuclear Information System (INIS)

    Villalba, L.; Montero-Cabrera, M. E.; Manjon-Collado, G.; Colmenero-Sujo, L.; Renteria-Villalobos, M.; Cano-Jimenez, A.; Rodriguez-Pineda, A.; Davila-Rangel, I.; Quirino-Torres, L.; Herrera-Peraza, E. F.

    2006-01-01

    The activity concentration of 222 Rn, 226 Ra and total uranium in groundwater samples collected from wells distributed throughout the state of Chihuahua has been measured. The values obtained of total uranium activity concentration in groundwater throughout the state run from -1 . Generally, radium activity concentration was -1 , with some exceptions; in spring water of San Diego de Alcala, in contrast, the value reached ∼5.3 Bq l -1 . Radon activity concentration obtained throughout the state was from 1.0 to 39.8 Bq l -1 . A linear correlation between uranium and radon dissolved in groundwater of individual wells was observed near Chihuahua City. Committed effective dose estimates for reference individuals were performed, with results as high as 134 μSv for infants in Aldama city. In Aldama and Chihuahua cities the average and many individual wells showed activity concentration values of uranium exceeding the Mexican norm of drinking water quality. (authors)

  9. Determination of Rn222 in samples of well water and domicile of the cities of Chihuahua and Aldama, Mexico

    International Nuclear Information System (INIS)

    Villalba, L.; Colmenero S, L.; Montero C, M.E.

    2004-01-01

    The study of the content of dissolved Rn 222 is presented in underground water and of domicile of the cities of Chihuahua and Aldama of the State of Chihuahua. The existence of the Rn 222 in the underground waters comes from its constant production in the rocks of the terrestrial bark. It has been determined that the radon is a noble gas of more solubility in the water, this solubility induces high concentrations in underground water, as well as bigger risk to the health in the human body once ingested or inhaled. Of the 32 wells studied in the cities of Chihuahua and Aldama, the content of dissolved Rn 222 in the water of 22 of them is bigger than 11 Bq/l and of 73 studied samples of water of domiciles 47 show bigger values that 11 Bq/l. These radon contents are attributable to the uraniferous rocks present in the aquifers. (Author)

  10. Confocal μ-XRF, μ-XAFS, and μ-XRD Studies of Sediment from a Nuclear Waste Disposal Natural Analogue Site and Fractured Granite Following a Radiotracer Migration Experiment

    International Nuclear Information System (INIS)

    Denecke, Melissa A.; Brendebach, Boris; Rothe, Joerg; Simon, Rolf; Janssens, Koen; Nolf, Wout de; Vekemans, Bart; Falkenberg, Gerald; Somogyi, Andrea; Noseck, Ulrich

    2007-01-01

    Combined μ-XRF, μ-XAFS, and μ-XRD investigations of a uranium-rich tertiary sediment, from a nuclear repository natural analogue site, and a fractured granite bore core section after a column tracer experiment using a Np(V) containing cocktail have been performed. Most μ-XRF/μ-XAFS measurements are recorded in a confocal geometry to provide added depth information. The U-rich sediment results show uranium to be present as a tetravalent phosphate and that U(IV) is associated with As(V). Arsenic present is either As(V) or As(0). The As(0) forms thin coatings on the surface of pyrite nodules. A hypothesis for the mechanism of uranium immobilization is proposed, where arsenopyrite acted as reductant of ground water dissolved U(VI) leading to precipitation of less soluble U(IV) and thereby forming As(V). Results for the granite sample show the immobilized Np to be tetravalent and associated with facture material

  11. Study of the total uranium in underground water in the city of Jimenez, Chihuahua; Estudio del uranio total en agua subterranea en la Ciudad de Jimenez, Chihuahua

    Energy Technology Data Exchange (ETDEWEB)

    Renteria V, M. [Centro de Investigacion de Materiales Avanzados (CIMAV), Av. Miguel de Cervantes Saavedra 120, 31109 Chihuahua (Mexico)]. e-mail: marusia.renteria@cimav.edu.mx

    2004-07-01

    Samples of water of wells in the city of Jimenez, Chihuahua were analyzed, and its were determined the content of total uranium. It was used the technique of extraction of uranium from water adding Bis ( 2- ethylexyl) phosphate and scintillating Beta plate Hi safe, and the measures of the activities were carried out in the portable scintillation detector Thiathler- O Y HIDEX. The obtained interval of concentrations was 0.12 to 0.26 Bq/l that it is finds below the maximum permissible limits that it manages the Mexican regulation. It was found a significant correlation among the concentration of uranium and those total solid dissolved present in the samples. (Author)

  12. Prevalence of rheumatic diseases in Raramuri people in Chihuahua, Mexico: a community-based study.

    Science.gov (United States)

    Del Río Nájera, Danyella; Santana, Natalia; Peláez-Ballestas, Ingris; González-Chávez, Susana A; Quiñonez-Flores, Celia M; Pacheco-Tena, César

    2016-07-01

    This study aimed to determine the prevalence of musculoskeletal (MSK) pain and rheumatic diseases in the Raramuri population (also known as Tarahumaras) who are an indigenous group in the northern state of Chihuahua in Mexico. We used the Community-Oriented Program for Control of Rheumatic Diseases (COPCORD) methodology. An analytical cross-sectional study was conducted including indigenous Raramuri aged ≥18 years from communities settled in Chihuahua City. Subjects with positive MSK pain were evaluated by primary care physicians and rheumatologists. Demographic and occupational factors such as gender and job type associated with rheumatic disease were investigated. A total of 380 indigenous Raramuri (mean age 33.6 ± 13.1 years; 37.9 % male) were interviewed. Seventy-six individuals (20 %) reported MSK pain in the last 7 days. Pain intensity was reported as "severe" and "the most severe" in 30 % of the cases. Fifty-six individuals (14.7 %) reported pain in the past and 86 (22.6 %) had either past or current pain. The prevalence of rheumatic diseases was 10.5 %. Diagnosed diseases were osteoarthritis (6.6 %), low back pain (1.6 %), spondyloarthritis (0.8 %), rheumatoid arthritis (0.5 %), non-specific arthritis (0.5 %), rheumatic regional pain syndromes (0.3 %), and fibromyalgia (0.3 %). Rheumatic disease was associated with the following variables: age (odds ratio (OR) 1.04, 95 % confidence interval (CI) 1.02-1.08; p = 0.006), family history of rheumatic symptoms (OR 6.9; 95 % CI 2.6-18.7; p rheumatic disease prevention program in the Raramuri people in Chihuahua, Mexico.

  13. A concurrent exposure to arsenic and fluoride from drinking water in Chihuahua, Mexico.

    Science.gov (United States)

    González-Horta, Carmen; Ballinas-Casarrubias, Lourdes; Sánchez-Ramírez, Blanca; Ishida, María C; Barrera-Hernández, Angel; Gutiérrez-Torres, Daniela; Zacarias, Olga L; Saunders, R Jesse; Drobná, Zuzana; Mendez, Michelle A; García-Vargas, Gonzalo; Loomis, Dana; Stýblo, Miroslav; Del Razo, Luz M

    2015-04-24

    Inorganic arsenic (iAs) and fluoride (F-) are naturally occurring drinking water contaminants. However, co-exposure to these contaminants and its effects on human health are understudied. The goal of this study was examined exposures to iAs and F- in Chihuahua, Mexico, where exposure to iAs in drinking water has been associated with adverse health effects. All 1119 eligible Chihuahua residents (>18 years) provided a sample of drinking water and spot urine samples. iAs and F- concentrations in water samples ranged from 0.1 to 419.8 µg As/L and from 0.05 to 11.8 mg F-/L. Urinary arsenic (U-tAs) and urinary F- (U-F-) levels ranged from 0.5 to 467.9 ng As/mL and from 0.1 to 14.4 µg F-/mL. A strong positive correlation was found between iAs and F- concentrations in drinking water (rs = 0.741). Similarly, U-tAs levels correlated positively with U-F- concentrations (rs = 0.633). These results show that Chihuahua residents exposed to high iAs concentrations in drinking water are also exposed to high levels of F-, raising questions about possible contribution of F- exposure to the adverse effects that have so far been attributed only to iAs exposure. Thus, investigation of possible interactions between iAs and F- exposures and its related health risks deserves immediate attention.

  14. [Depression in older adults with extreme poverty belonging to Social Program in City Juarez, Chihuahua, Mexico].

    Science.gov (United States)

    Flores-Padilla, Luis; Ramírez-Martínez, Flor Rocío; Trueba-Gómez, Rocío

    2016-01-01

    To identify depression in older adults living in extreme poverty beneficiaries of social program in City Juarez, Chihuahua. Analytical study in 941 adults > 60 years, studied variables: age, sex, marital status, education and work, extreme poverty, place of residence, asylum. Yesavage Geriatric scale was used. X², IC poverty depression is greater than that reported in the literature. The support granted by the Mexican Government to social programs that benefit older adults should be planned strategically with aims on improving the long-term health.

  15. Clinical and neuropathological findings of acute carbon monoxide toxicity in chihuahuas following smoke inhalation.

    Science.gov (United States)

    Kent, Marc; Creevy, Kate E; Delahunta, Alexander

    2010-01-01

    Three adult Chihuahuas were presented for evaluation after smoke inhalation during a house fire. All three dogs received supportive care and supplemental oxygen. After initial improvement, the dogs developed seizures. Despite anticonvulsant therapy and supportive care, the dogs died. The brains of two dogs were examined. Lesions were identified that were compatible with acute carbon monoxide (CO) toxicity. Lesions were confined to the caudate nucleus, the globus pallidus, and the substantia nigra bilaterally, as well as the cerebellum, cerebral cortex, and dorsal thalamus. This case report describes the clinicopathological sequelae in acute CO toxicity.

  16. Radon concentrations in ground and drinking water in the state of Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Villalba, L.; Colmenero Sujo, L.; Montero Cabrera, M.E.; Cano Jimenez, A.; Renteria Villalobos, M.; Delgado Mendoza, C.J.; Jurado Tenorio, L.A.; Davila Rangel, I.; Herrera Peraza, E.F.

    2005-01-01

    This paper reports 222 Rn concentrations in ground and drinking water of nine cities of Chihuahua State, Mexico. Fifty percent of the 114 sampled wells exhibited 222 Rn concentrations exceeding 11 Bq/L, the maximum contaminant level (MCL) recommended by the USEPA. Furthermore, around 48% (123 samples) of the tap-water samples taken from 255 dwellings showed radon concentrations over the MCL. There is an apparent correlation between total dissolved solids and radon concentration in ground-water. The high levels of 222 Rn found may be entirely attributed to the nature of aquifer rocks

  17. Radon concentrations in ground and drinking water in the state of Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Villalba, L. [Centro de Investigacion en Materiales Avanzados, S.C., Miguel de Cervantes 120, Complejo Industrial Chihuahua, CP 31109 Chihuahua, Chih. (Mexico); Colmenero Sujo, L. [Centro de Investigacion en Materiales Avanzados, S.C., Miguel de Cervantes 120, Complejo Industrial Chihuahua, CP 31109 Chihuahua, Chih. (Mexico); Instituto Tecnologico de Chihuahua II, Ave. de las Industrias 11101, Chihuahua, Chih. (Mexico); Montero Cabrera, M.E. [Centro de Investigacion en Materiales Avanzados, S.C., Miguel de Cervantes 120, Complejo Industrial Chihuahua, CP 31109 Chihuahua, Chih. (Mexico)]. E-mail: elena.montero@cimav.edu.mx; Cano Jimenez, A. [Centro de Investigacion en Materiales Avanzados, S.C., Miguel de Cervantes 120, Complejo Industrial Chihuahua, CP 31109 Chihuahua, Chih. (Mexico); Renteria Villalobos, M. [Centro de Investigacion en Materiales Avanzados, S.C., Miguel de Cervantes 120, Complejo Industrial Chihuahua, CP 31109 Chihuahua, Chih. (Mexico); Delgado Mendoza, C.J. [Facultad de Ciencias Quimicas, Universidad Autonoma de Chihuahua, Ciudad Universitaria S/N, Chihuahua, Chih. (Mexico); Jurado Tenorio, L.A. [Facultad de Ciencias Quimicas, Universidad Autonoma de Chihuahua, Ciudad Universitaria S/N, Chihuahua, Chih. (Mexico); Davila Rangel, I. [Centro Regional de Estudios Nucleares, Universidad Autonoma de Zacatecas, Cipres 20, Zacatecas, Zac. (Mexico); Herrera Peraza, E.F. [Centro de Investigacion en Materiales Avanzados, S.C., Miguel de Cervantes 120, Complejo Industrial Chihuahua, CP 31109 Chihuahua, Chih. (Mexico)

    2005-07-01

    This paper reports {sup 222}Rn concentrations in ground and drinking water of nine cities of Chihuahua State, Mexico. Fifty percent of the 114 sampled wells exhibited {sup 222}Rn concentrations exceeding 11 Bq/L, the maximum contaminant level (MCL) recommended by the USEPA. Furthermore, around 48% (123 samples) of the tap-water samples taken from 255 dwellings showed radon concentrations over the MCL. There is an apparent correlation between total dissolved solids and radon concentration in ground-water. The high levels of {sup 222}Rn found may be entirely attributed to the nature of aquifer rocks.

  18. Radon concentrations in ground and drinking water in the state of Chihuahua, Mexico.

    Science.gov (United States)

    Villalba, L; Colmenero Sujo, L; Montero Cabrera, M E; Cano Jiménez, A; Rentería Villalobos, M; Delgado Mendoza, C J; Jurado Tenorio, L A; Dávila Rangel, I; Herrera Peraza, E F

    2005-01-01

    This paper reports (222)Rn concentrations in ground and drinking water of nine cities of Chihuahua State, Mexico. Fifty percent of the 114 sampled wells exhibited (222)Rn concentrations exceeding 11Bq/L, the maximum contaminant level (MCL) recommended by the USEPA. Furthermore, around 48% (123 samples) of the tap-water samples taken from 255 dwellings showed radon concentrations over the MCL. There is an apparent correlation between total dissolved solids and radon concentration in ground-water. The high levels of (222)Rn found may be entirely attributed to the nature of aquifer rocks.

  19. ACTINOMYCIN D ANALOGUES

    DEFF Research Database (Denmark)

    1997-01-01

    The present invention relates to new compounds being structurally and functionally similar to Actinomycin D and to combinatorial libraries of such compounds. The Actinomycin D analogues according to the present invention comprise two linear or cyclic peptide moieties constituted by $g...

  20. Cobalamin analogues in humans

    DEFF Research Database (Denmark)

    Hardlei, Tore Forsingdal; Obeid, Rima; Herrmann, Wolfgang

    2013-01-01

    BACKGROUND: Haptocorrin (HC) carries cobalamin analogues (CorA), but whether CorA are produced in the body is unknown. All cobalamins (Cbl) to the foetus are delivered by the Cbl-specific protein transcobalamin (TC), and therefore analysis of cord serum for CorA may help to clarify the origin...

  1. UK Natural Analogue Coordinating Group: fourth annual report

    International Nuclear Information System (INIS)

    Read, D.; Hooker, P.J.

    1992-01-01

    HMIP has a research programme investigating some naturally radioactive sites as geochemical analogues of radionuclide migration. All of the analogue sites under investigation, both in the U.K. and overseas, are located where elevated uranium concentrations occur naturally. Coordination of the programme is achieved through the UK Natural Analogue Co-ordinating Group (NACG) which has met three times in this reporting period. The NACG is steered by the British Geological Survey. Its purpose is to ensure that the different research projects have an integrated function aimed at increasing our understanding of natural geochemical processes. Effort is also being expended in testing research models which may be used in such assessments. (author)

  2. The Valles natural analogue project

    International Nuclear Information System (INIS)

    Stockman, H.; Krumhansl, J.; Ho, C.; McConnell, V.

    1994-12-01

    The contact between an obsidian flow and a steep-walled tuff canyon was examined as an analogue for a highlevel waste repository. The analogue site is located in the Valles Caldera in New Mexico, where a massive obsidian flow filled a paleocanyon in the Battleship Rock tuff. The obsidian flow provided a heat source, analogous to waste panels or an igneous intrusion in a repository, and caused evaporation and migration of water. The tuff and obsidian samples were analyzed for major and trace elements and mineralogy by INAA, XRF, X-ray diffraction; and scanning electron microscopy and electron microprobe. Samples were also analyzed for D/H and 39 Ar/ 4O isotopic composition. Overall,the effects of the heating event seem to have been slight and limited to the tuff nearest the contact. There is some evidence of devitrification and migration of volatiles in the tuff within 10 meters of the contact, but variations in major and trace element chemistry are small and difficult to distinguish from the natural (pre-heating) variability of the rocks

  3. CEC natural analogue working group

    International Nuclear Information System (INIS)

    Come, B.; Chapman, N.A.

    1986-01-01

    The second meeting of the CEC Natural Analogue Working Group took place on June 17-19, 1986, hosted by the Swiss NAGRA in Interlaken (CH). A review of recent progress in natural analogue programmes was carried out, and complemented by detailed discussions about geomicrobiology, archaeological analogues, natural colloids, and use of analogues to increase confidence in safety assessments for radioactive waste disposal. A statement drafted by the Group, and the presentations made, are put together in this report

  4. CEC Natural Analogue Working Group

    International Nuclear Information System (INIS)

    Come, B.; Chapman, N.A.

    1989-01-01

    The central theme for the third meeting of the CEC analogue working group was ''How can analogue data be used for performance assessments, both in support of the results and for presentation to the public''. This report puts together the most recent achievements in this field, together with a review of on-going natural analogue programmes

  5. Radiation-Induced Defects in Kaolinite as Tracers of Past Occurrence of Radionuclides in a Natural Analogue of High Level Nuclear Waste Repository

    Science.gov (United States)

    Allard, T.; Fourdrin, C.; Calas, G.

    2007-05-01

    Understanding the processes controlling migrations of radioelements at the Earth's surface is an important issue for the long-term safety assessment of high level nuclear waste repositories (HLNWR). Evidence of past occurrence and transfer of radionuclides can be found using radiation-induced defects in minerals. Clay minerals are particularly relevant because of their widespread occurrence at the Earth's surface and their finely divided nature which provides high contact area with radioactive fluids. Owing to its sensitivity to radiations, kaolinite can be used as natural, in situ dosimeter. Kaolinite is known to contain radiation-induced defects which are detected by Electron Paramagnetic Resonance. They are differentiated by their nature, their production kinetics and their thermal stability. One of these defects is stable at the scale of geological periods and provides a record of past radionuclide occurrence. Based on artificial irradiations, a methodology has been subsequently proposed to determine paleodose cumulated by kaolinite since its formation. The paleodose can be used to derive equivalent radioelement concentrations, provided that the age of kaolinite formation can be constrained. This allows quantitative reconstruction of past transfers of radioelements in natural systems. An example is given for the Nopal I U-deposit (Chihuahua, Mexico), hosted in hydrothermally altered volcanic tufs and considered as analogue of the Yucca Mountain site. The paleodoses experienced by kaolinites were determined from the concentration of defects and dosimetry parameters of experimental irradiations. Using few geochemical assumption, a equivalent U-content responsible for defects in kaolinite was calculated from the paleodose, a dose rate balance and model ages of kaolinites constrained by tectonic phases. In a former study, the ages were assumptions derived from regional tectonic events. In thepresent study, ages of mineralization events are measured from U

  6. Prevalencia de displasia y cáncer cervicouterino y factores asociados en el Hospital Central de Chihuahua, México

    OpenAIRE

    Ivonne Salas-Urrutia; Eyra Alejandra Villalobos; Brenda Lizeth Ramírez-Vega

    2006-01-01

    Objetivos: Los objetivos del presente estudio fueron determinar la prevalencia y los factores de riesgo asociados a cáncer cervicouterino en; las mujeres que acuden al Hospital Central de Chihuahua en el 2004 ya que no se cuenta registros de esta entidad en la ciudad de Chihuahua.; Material y Métodos: Se realizó un estudio observacional, transversal, donde se incluyó a mujeres que demandaron realizarse la citología; cervical en el Hospital Central del Estado de Chihuahua, en el año 2...

  7. Bioluminescence of beetle luciferases with 6'-amino-D-luciferin analogues reveals excited keto-oxyluciferin as the emitter and phenolate/luciferin binding site interactions modulate bioluminescence colors.

    Science.gov (United States)

    Viviani, Vadim R; Neves, Deimison Rodrigues; Amaral, Danilo Trabuco; Prado, Rogilene A; Matsuhashi, Takuto; Hirano, Takashi

    2014-08-19

    Beetle luciferases produce different bioluminescence colors from green to red using the same d-luciferin substrate. Despite many studies of the mechanisms and structural determinants of bioluminescence colors with firefly luciferases, the identity of the emitters and the specific active site interactions responsible for bioluminescence color modulation remain elusive. To address these questions, we analyzed the bioluminescence spectra with 6'-amino-D-luciferin (aminoluciferin) and its 5,5-dimethyl analogue using a set of recombinant beetle luciferases that naturally elicit different colors and different pH sensitivities (pH-sensitive, Amydetes vivianii λmax=538 nm, Macrolampis sp2 λmax=564 nm; pH-insensitive, Phrixotrix hirtus λmax=623 nm, Phrixotrix vivianii λmax=546 nm, and Pyrearinus termitilluminans λmax=534 nm), a luciferase-like enzyme (Tenebrionidae, Zophobas morio λmax=613 nm), and mutants of C311 (S314). The green-yellow-emitting luciferases display red-shifted bioluminescence spectra with aminoluciferin in relation to those with D-luciferin, whereas the red-emitting luciferases displayed blue-shifted spectra. Bioluminescence spectra with 5,5-dimethylaminoluciferin, in which enolization is blocked, were almost identical to those of aminoluciferin. Fluorescence probing using 2-(4-toluidino)naphthalene-6-sulfonate and inference with aminoluciferin confirm that the luciferin binding site of the red-shifted luciferases is more polar than in the case of the green-yellow-emitting luciferases. Altogether, the results show that the keto form of excited oxyluciferin is the emitter in beetle bioluminescence and that bioluminescence colors are essentially modulated by interactions of the 6'-hydroxy group of oxyluciferin and basic moieties under the influence of the microenvironment polarity of the active site: a strong interaction between a base moiety and oxyluciferin phenol in a hydrophobic microenvironment promotes green-yellow emission, whereas a more polar

  8. Spatial analysis techniques applied to uranium prospecting in Chihuahua State, Mexico

    Science.gov (United States)

    Hinojosa de la Garza, Octavio R.; Montero Cabrera, María Elena; Sanín, Luz H.; Reyes Cortés, Manuel; Martínez Meyer, Enrique

    2014-07-01

    To estimate the distribution of uranium minerals in Chihuahua, the advanced statistical model "Maximun Entropy Method" (MaxEnt) was applied. A distinguishing feature of this method is that it can fit more complex models in case of small datasets (x and y data), as is the location of uranium ores in the State of Chihuahua. For georeferencing uranium ores, a database from the United States Geological Survey and workgroup of experts in Mexico was used. The main contribution of this paper is the proposal of maximum entropy techniques to obtain the mineral's potential distribution. For this model were used 24 environmental layers like topography, gravimetry, climate (worldclim), soil properties and others that were useful to project the uranium's distribution across the study area. For the validation of the places predicted by the model, comparisons were done with other research of the Mexican Service of Geological Survey, with direct exploration of specific areas and by talks with former exploration workers of the enterprise "Uranio de Mexico". Results. New uranium areas predicted by the model were validated, finding some relationship between the model predictions and geological faults. Conclusions. Modeling by spatial analysis provides additional information to the energy and mineral resources sectors.

  9. Arsenic in freshwater fish in the Chihuahua County water reservoirs (Mexico).

    Science.gov (United States)

    Nevárez, Myrna; Moreno, Myriam Verónica; Sosa, Manuel; Bundschuh, Jochen

    2011-01-01

    Water reservoirs in Chihuahua County, Mexico, are affected by some punctual and non-punctual geogenic and anthropogenic pollution sources; fish are located at the top of the food chain and are good indicators for the ecosystems pollution. The study goal was to: (i) determine arsenic concentration in fish collected from the Chuviscar, Chihuahua, San Marcos and El Rejon water reservoirs; (ii) to assess if the fishes are suitable for human consumption and (iii) link the arsenic contents in fish with those in sediment and water reported in studies made the same year for these water reservoirs. Sampling was done in summer, fall and winter. The highest arsenic concentration in the species varied through the sampling periods: Channel catfish (Ictalurus punctatus) with 0.22 ± 0.15 mg/kg dw in winter and Green sunfish (Lepomis cyanellus) with 2.00 ± 0.15 mg/kg dw in summer in El Rejon water reservoir. A positive correlation of arsenic contents was found through all sampling seasons in fish samples and the samples of sediment and water. The contribution of the weekly intake of inorganic arsenic, based on the consumption of 0.245 kg fish muscles/body weight/week was found lower than the acceptable weekly intake of 0.015 mg/kg/body weight for inorganic arsenic suggested by FAO/WHO.

  10. La vivienda nueva en la ciudad de Chihuahua: oferta y demanda

    Directory of Open Access Journals (Sweden)

    María de Lourdes Romo-Aguilar

    2012-01-01

    Full Text Available El objetivo del presente artículo es analizar el papel del gobierno y del mercado inmobiliario en relación con la disponibilidad de vivienda nueva en la ciudad de Chihuahua en el periodo 2000-2005, no sólo en términos cuantitativos sino también en calidad en cuanto a que tenga las características que le permitan satisfacer las necesidades básicas de las familias, como lo define la agenda internacional denominada Habitat, éstas son: espacio suficiente, seguridad y disponibilidad de servicios, entre otros. Para ello, este trabajo se divide en seis apartados: 1 apuntes teórico-conceptuales sobre la vivienda; 2 desarrollo institucional de atención a la vivienda en México; 3 dinámica de crecimiento de la ciudad de Chihuahua; 4 características de la vivienda tradicional y nueva; 5 oferta de vivienda nueva para el caso particular, y 6 demanda de vivienda. Finalmente se presentan las conclusiones sobre el tema.

  11. Survival and sprouting responses of Chihuahua Pine after the Rodeo-Chediski Fire on the Mogollon Rim, Arizona

    Science.gov (United States)

    Kenneth H. Baumgartner; Peter Z. Fule

    2007-01-01

    Chihuahua pines (Pinus leiophylla Schiede and Deppe var. chihuahuana Engelmann) were surveyed on 11 study plots on the Mogollon Rim in east central Arizona to compare characteristics of trees that sprouted from the base or root collar after the Rodeo-Chediski fire with those of trees that did not sprout. The differences in trees...

  12. Recent evolution and divergence among populations of a rare Mexican endemic, Chihuahua spruce, following holocene climatic warming

    Science.gov (United States)

    F. Thomas Ledig; Virginia Jacob-Cervantes; Paul D. Hodgskiss

    1997-01-01

    Fragmentation and reduction in population size are expected to reduce genetic diversity. However, examples from natural populations of forest trees are scarce. The range of Chihuahua spruce retreated northward and fragmented coincident with the warming climate that marked the early Holocene. The isolated populations vary from 15 to 2441 trees, which provided an...

  13. REGIONAL HYDROLOGY OF THE NOPAL 1 SITE, SIERRA PENA BLANCA, CHIHUAHUA, MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    J.A. Rodriguez-Pineda; P. Goodell; P. Dobson; J. Walton; R. Olver; R. de la Garza; S. Harder

    2005-10-01

    The objectives of this report are: (1) Determine the main source of the groundwater (GW) found within the DOE wells (PB-1, PB-2, and PB-3); and (2) Determine whether the Nopal I GW has any relationship to the connectivity between the regional Encinillas Aquifer to the west and the El Cuervo Aquifer to the east.

  14. Natural analogue working group

    International Nuclear Information System (INIS)

    Come, B.; Chapman, N.

    1986-01-01

    A Natural Analogue Working Group was established by the Commission of the European Communities in 1985. The purpose of this group is to bring together modellers with earth scientists and others, so that maximum benefit can be obtained from natural analogue studies with a view to safe geological disposal of radioactive waste. The first meeting of this group was held in Brussels from November 5 to 7, 1985. The discussions mainly concerned the identification of the modellers' needs and of the earth scientists' capacity to provide for them. Following the debates, a written statement was produced by the Group; this document forms the core of the present Report. Notes and outlines of many of the presentations made are grouped in four appendixes. The valuable contribution of all those involved in the meeting is gratefully acknowledged

  15. Aspartame and Its Analogues

    Science.gov (United States)

    Pavlova, L. A.; Komarova, T. V.; Davidovich, Yurii A.; Rogozhin, S. V.

    1981-04-01

    The results of studies on the biochemistry of the sweet taste are briefly reviewed. The methods of synthesis of "aspartame" — a sweet dipeptide — are considered, its structural analogues are described, and quantitative estimates are made of the degree of sweetness relative to sucrose. Attention is concentrated mainly on problems of the relation between the structure of the substance and its taste in the series of aspartyl derivatives. The bibliography includes 118 references.

  16. Quantum analogue computing.

    Science.gov (United States)

    Kendon, Vivien M; Nemoto, Kae; Munro, William J

    2010-08-13

    We briefly review what a quantum computer is, what it promises to do for us and why it is so hard to build one. Among the first applications anticipated to bear fruit is the quantum simulation of quantum systems. While most quantum computation is an extension of classical digital computation, quantum simulation differs fundamentally in how the data are encoded in the quantum computer. To perform a quantum simulation, the Hilbert space of the system to be simulated is mapped directly onto the Hilbert space of the (logical) qubits in the quantum computer. This type of direct correspondence is how data are encoded in a classical analogue computer. There is no binary encoding, and increasing precision becomes exponentially costly: an extra bit of precision doubles the size of the computer. This has important consequences for both the precision and error-correction requirements of quantum simulation, and significant open questions remain about its practicality. It also means that the quantum version of analogue computers, continuous-variable quantum computers, becomes an equally efficient architecture for quantum simulation. Lessons from past use of classical analogue computers can help us to build better quantum simulators in future.

  17. Uncertainties and credibility building of safety analyses. Natural analogues

    International Nuclear Information System (INIS)

    Laciok, A.

    2001-07-01

    The substance of natural analogues and their studies is defined as a complementary method to laboratory and in-situ experiments and modelling. The role of natural analogues in the processes of development of repositories is defined, mainly in performance assessment of repository system and communication with public. The criteria for identification of natural analogues which should be evaluated in the phase of initiation of new studies are specified. Review part of this report is divided to study of natural analogues and study of anthropogenic and industrial analogues. The main natural analogue studies performed in various countries, in different geological setting, with various aims are characterized. New results acquired in recently finished studies are included: Palmottu (2nd phase of project financed by European Commission), Oklo (results of research financed also by European Commission), Maqarin (3rd phase) and other information obtained from last meetings and workshops of NAWG. In view of the fact that programmes of development of deep repositories in Czech and Slovak Republics are interconnected, the natural analogues studies carried out in the Czech republic are incorporated in separate chapter - study of uranium accumulation in Tertiary clays at Ruprechtov site and study of degradation of natural glasses. In final part the areas of natural analogue studies as an integral part of development of deep geological repository are proposed along with characterization of broader context and aspects of realization of these studies (international cooperation, preparation and evaluation of procedures, communication with public). (author)

  18. Investigation of the radioactivity in air, water and soil in the Estado de Chihuahua; Investigacion de la radiactividad en aire, agua y suelo en el Estado de Chihuahua

    Energy Technology Data Exchange (ETDEWEB)

    Montero C, M.E.; Renteria V, M.; Herrera P, E.F.; Villalba, M.L. [Centro de Investigacion en Materiales Avanzados, S. C., Miguel de Cervantes 120, Complejo Industrial Chihuahua, C.P. 31109, Chihuahua (Mexico); Colmenero S, L.H. [CIMAV e Instituto Tecnologico de Chihuahua, Av. de las Industrias 11101, Chihuahua (Mexico)]. e-mail: elena.montero@cimav.edu.mx

    2004-07-01

    The results of the determinations of activities of the series of U-238, Th-232 and the K-40 in soils, of the Rn-222 in the air of the domiciles, and in underground water are presented, as well as the total uranium activity in underground water, product of an extensive sampling in the state of Chihuahua. In two of the aquifers a positive correlation was obtained among the concentration of total uranium and the Rn-222 dissolved in the water of each well. Also it was finds a positive tendency among the averages of the concentration of U-238 in the soil and of the concentration of Rn-222 in the air of the domiciles in different towns, and among the averages of the concentration of U-238 in the floor and of the concentration of the Rn-222 dissolved in the well water in different aquifer. It is suggested that the constitution for rocks more or less uraniferous of the alluvial valleys gives explanation to the observed correlations. (Author)

  19. Revealing Television's Analogue Heroes

    Directory of Open Access Journals (Sweden)

    Vanessa Jackson

    2013-12-01

    Full Text Available In this article I will argue that we need to create new archival models in order to preserve and share knowledge of historical, ‘hidden’ television professions and production cultures. Oral history traditions of recording life stories give us a useful starting point. Engineering ‘encounters’ between skilled television technicians, and the now obsolete equipment they operated in the 1970s and 80s, is challenging for a myriad of reasons, but videoing the interaction of man and machine provides us with a rich insight into how analogue television was produced and broadcast. Social media enables us to disseminate these histories in new and innovative ways..

  20. Uranium in the Surrounding of San Marcos-Sacramento River Environment (Chihuahua, Mexico)

    Science.gov (United States)

    Rentería-Villalobos, Marusia; Cortés, Manuel Reyes; Mantero, Juan; Manjón, Guillermo; García-Tenorio, Rafael; Herrera, Eduardo; Montero-Cabrera, Maria Elena

    2012-01-01

    The main interest of this study is to assess whether uranium deposits located in the San Marcos outcrops (NW of Chihuahua City, Mexico) could be considered as a source of U-isotopes in its surrounding environment. Uranium activity concentrations were determined in biota, ground, and surface water by either alpha or liquid scintillation spectrometries. Major ions were analyzed by ICP-OES in surface water and its suspended matter. For determining uranium activity in biota, samples were divided in parts. The results have shown a possible lixiviation and infiltration of uranium from geological substrate into the ground and surface water, and consequently, a transfer to biota. Calculated annual effective doses by ingestion suggest that U-isotopes in biota could not negligibly contribute to the neighboring population dose. By all these considerations, it is concluded that in this zone there is natural enhancement of uranium in all environmental samples analyzed in the present work. PMID:22536148

  1. Social acceptability urban form and sustainability in urban neighborhoods in Ciudad Juárez, Chihuahua

    Directory of Open Access Journals (Sweden)

    Claudia Gabriela Vargas Fernández

    2016-11-01

    Full Text Available In the field of urban planning, questioning around sustainability and the possibility of sustainable urban planning has led to a new set of approaches and discussions that impact studies on urban form and sustainable livelihoods. This approach characterized the work presented by Mike Jenks and Colin Jones (2010, Dimensions of the Sustainable City, where a set of variables are presented about urban sustainability from the neighbourhood level of analysis. In that sense, this article proposes the analysis of three social housing neighborhoods in Ciudad Juárez, Chihuahua, México, integrating aspects of urban form and social acceptability, in order to understand the relationship between the physical and sociocultural dimensions of the concept of urban sustainability.

  2. La investigación educativa en Chihuahua, campo de oportunidades

    Directory of Open Access Journals (Sweden)

    Jesús Adolfo Trujillo Holguín

    2016-10-01

    Full Text Available El crecimiento que experimenta el campo de la investigación educativa en el estado de Chihuahua, durante los últimos años, es notorio. Las y los investigadores locales ocupan espacios académicos en redes y grupos de investigación nacionales e internacionales, se incorporan al Sistema Nacional de Investigadores (SNI, compiten por recursos en programas públicos de apoyo a la investigación científica, participan en congresos y encuentros de investigación más allá de las fronteras estatales, organizan y promueven congresos para atraer investigadores de distintas latitudes, publican libros y artículos y –en suma– son protagonistas del quehacer investigativo del país.

  3. Study of the total uranium in underground water in the city of Jimenez, Chihuahua

    International Nuclear Information System (INIS)

    Renteria V, M.

    2004-01-01

    Samples of water of wells in the city of Jimenez, Chihuahua were analyzed, and its were determined the content of total uranium. It was used the technique of extraction of uranium from water adding Bis ( 2- ethylexyl) phosphate and scintillating Beta plate Hi safe, and the measures of the activities were carried out in the portable scintillation detector Thiathler- O Y HIDEX. The obtained interval of concentrations was 0.12 to 0.26 Bq/l that it is finds below the maximum permissible limits that it manages the Mexican regulation. It was found a significant correlation among the concentration of uranium and those total solid dissolved present in the samples. (Author)

  4. DEL NEOCORPORATIVISMO A NIVEL FABRIL MAQUILADORAS Y SINDICATOS EN LA CIUDAD DE CHIHUAHUA, MÉXICO

    Directory of Open Access Journals (Sweden)

    Patricia Ravelo

    2000-01-01

    Full Text Available En este ensayo buscamos responder una pregunta: ¿Existe en las maquiladoras de exportación de la ciudad de Chihuahua, en el norte industrializado de México, una nueva relación entre el trabajo y el capital, un vínculo neocorporativo? Para dilucidar esta cuestión abordamos varias dimensiones de tal relación entre trabajo y capital: organización del trabajo y empleo; proceso de trabajo; salario; prestaciones sindicales y regresión de derechos. Es una visión pesimista sobre estas relaciones en los "nuevos" contextos de industrialización, pero que, con todo, alcanza a ver un futuro más promisorio para el trabajo.

  5. Exposure Assessment to Environmental Chemicals in Children from Ciudad Juarez, Chihuahua, Mexico.

    Science.gov (United States)

    Ochoa-Martinez, Angeles C; Orta-Garcia, Sandra T; Rico-Escobar, Edna M; Carrizales-Yañez, Leticia; Del Campo, Jorge D Martin; Pruneda-Alvarez, Lucia G; Ruiz-Vera, Tania; Gonzalez-Palomo, Ana K; Piña-Lopez, Iris G; Torres-Dosal, Arturo; Pérez-Maldonado, Ivan N

    2016-05-01

    It has been demonstrated that the human biomonitoring of susceptible populations is a valuable method for the identification of critical contaminants. Therefore, the purpose of this study was to assess the exposure profile for arsenic (As), lead (Pb), mercury (Hg), 1-hydroxypyrene (1-OHP), 1,1-bis(p-chlorophenyl)-2,2,2-trichloroethane (DDT), 1,1-dichloro-2,2-bis(p-chlorophenyl) ethylene (DDE), polybrominated diphenyl ethers (PBDEs), and polychlorinated biphenyls (PCBs) in children living in Ciudad Juarez, Chihuahua, Mexico (a major manufacturing center in Mexico). In 2012, we evaluated a total of 135 healthy children living in Ciudad Juarez since birth. The total PBDEs levels ranged from nondetectable (exposure levels to chemicals analyzed in the children living in the study community. Therefore, a biomonitoring program for the surveillance of the child population in Ciudad Juarez is necessary.

  6. Del neocorporativismo a nivel fabril maquiladoras y sindicatos en la ciudad de chihuahua, México

    Directory of Open Access Journals (Sweden)

    Sergio Sánchez

    2000-04-01

    Full Text Available En este ensayo buscamos responder una pregunta: ¿Existe en las maquiladoras de exportación de la ciudad de Chihuahua, en el norte industrializado de México, una nueva relación entre el trabajo y el capital, un vínculo neocorporativo? Para dilucidar esta cuestión abordamos varias dimensiones de tal relación entre trabajo y capital: organización del trabajo y empleo; proceso de trabajo; salario; prestaciones sindicales y regresión de derechos. Es una visión pesimista sobre estas relaciones en los “nuevos” contextos de industrialización, pero que, con todo, alcanza a ver un futuro más promisorio para el trabajo.

  7. Investigación educativa: la experiencia en el estado de Chihuahua

    Directory of Open Access Journals (Sweden)

    Evangelina Cervantes Holguín

    2016-04-01

    Full Text Available Este ensayo tiene como propósito recuperar las experiencias de investigación de los académicos e instituciones superiores establecidas en la región. Asimismo, permite conocer el estado que guarda esta actividad intelectual y el desarrollo que ha tenido el campo de la educación en el estado de Chihuahua. De manera concreta se establecen cuatro etapas: antecedentes, primeras experiencias de investigación (1984 a 1990; cambios y desafíos (1990 al 2000; crecimiento (2000 al 2009 y apertura y expansión (2009. En esta última fase, se destaca la pertinencia de la Rediech como espacio para generar, desarrollar, fortalecer y difundir la actividad investigativa en esta entidad.

  8. Coliform and Metal Contamination in Lago de Colina, a Recreational Water Body in Chihuahua State, Mexico

    Science.gov (United States)

    Rubio-Arias, Hector; Rey, Nora I.; Quintana, Rey M.; Nevarez, G. Virginia; Palacios, Oskar

    2011-01-01

    Lago de Colina (Colina Lake) is located about 180 km south of the city of Chihuahua (Mexico), and during the Semana Santa (Holy Week) vacation period its recreational use is high. The objective of this study was to quantify coliform and heavy metal levels in this water body before and after the Holy Week vacation period in 2010. Twenty sampling points were randomly selected and two water samples were collected at each point near the surface (0.30 m) and at 1 m depth. After the Holy Week vacation the same twenty points were sampled at the same depths. Therefore, a total 80 water samples were analyzed for fecal and total coliforms and levels of the following metals: Al, As, B, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Se, Si and Zn. It was hypothesized that domestic tourism contaminated this water body, and as a consequence, could have a negative impact on visitor health. An analysis of variance (ANOVA) study was performed for each element and its interactions considering a factorial design where factor A was sample date and factor B was sample depth. Fecal coliforms were only detected at eight sampling points in the first week, but after Holy Week, both fecal and total coliforms were detected at most sampling points. The concentrations of Al, B, Na, Ni and Se were only statistically different for factor A. The levels of Cr, Cu, K and Mg was different for both date and depth, but the dual factor interaction was not significant. The amount of Ca and Zn was statistically different due to date, depth and their interaction. No significant differences were found for any factor or the interaction for the elements As, Fe and Mn. Because of the consistent results, it is concluded that local tourism is contaminating the recreational area of Colina Lake, Chihuahua, Mexico. PMID:21776236

  9. Coliform and Metal Contamination in Lago de Colina, a Recreational Water Body in Chihuahua State, Mexico

    Directory of Open Access Journals (Sweden)

    Hector Rubio-Arias

    2011-06-01

    Full Text Available Lago de Colina (Colina Lake is located about 180 km south of the city of Chihuahua (Mexico, and during the Semana Santa (Holy Week vacation period its recreational use is high. The objective of this study was to quantify coliform and heavy metal levels in this water body before and after the Holy Week vacation period in 2010. Twenty sampling points were randomly selected and two water samples were collected at each point near the surface (0.30 m and at 1 m depth. After the Holy Week vacation the same twenty points were sampled at the same depths. Therefore, a total 80 water samples were analyzed for fecal and total coliforms and levels of the following metals: Al, As, B, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Se, Si and Zn. It was hypothesized that domestic tourism contaminated this water body, and as a consequence, could have a negative impact on visitor health. An analysis of variance (ANOVA study was performed for each element and its interactions considering a factorial design where factor A was sample date and factor B was sample depth. Fecal coliforms were only detected at eight sampling points in the first week, but after Holy Week, both fecal and total coliforms were detected at most sampling points. The concentrations of Al, B, Na, Ni and Se were only statistically different for factor A. The levels of Cr, Cu, K and Mg was different for both date and depth, but the dual factor interaction was not significant. The amount of Ca and Zn was statistically different due to date, depth and their interaction. No significant differences were found for any factor or the interaction for the elements As, Fe and Mn. Because of the consistent results, it is concluded that local tourism is contaminating the recreational area of Colina Lake, Chihuahua, Mexico.

  10. Coliform and metal contamination in Lago de Colina, a recreational water body in Chihuahua State, Mexico.

    Science.gov (United States)

    Rubio-Arias, Hector; Rey, Nora I; Quintana, Rey M; Nevarez, G Virginia; Palacios, Oskar

    2011-06-01

    Lago de Colina (Colina Lake) is located about 180 km south of the city of Chihuahua (Mexico), and during the Semana Santa (Holy Week) vacation period its recreational use is high. The objective of this study was to quantify coliform and heavy metal levels in this water body before and after the Holy Week vacation period in 2010. Twenty sampling points were randomly selected and two water samples were collected at each point near the surface (0.30 m) and at 1 m depth. After the Holy Week vacation the same twenty points were sampled at the same depths. Therefore, a total 80 water samples were analyzed for fecal and total coliforms and levels of the following metals: Al, As, B, Ca, Cr, Cu, Fe, K, Mg, Mn, Na, Ni, Pb, Se, Si and Zn. It was hypothesized that domestic tourism contaminated this water body, and as a consequence, could have a negative impact on visitor health. An analysis of variance (ANOVA) study was performed for each element and its interactions considering a factorial design where factor A was sample date and factor B was sample depth. Fecal coliforms were only detected at eight sampling points in the first week, but after Holy Week, both fecal and total coliforms were detected at most sampling points. The concentrations of Al, B, Na, Ni and Se were only statistically different for factor A. The levels of Cr, Cu, K and Mg was different for both date and depth, but the dual factor interaction was not significant. The amount of Ca and Zn was statistically different due to date, depth and their interaction. No significant differences were found for any factor or the interaction for the elements As, Fe and Mn. Because of the consistent results, it is concluded that local tourism is contaminating the recreational area of Colina Lake, Chihuahua, Mexico.

  11. Studies of natural analogues and geological systems

    International Nuclear Information System (INIS)

    Brandberg, F.; Grundfelt, B.; Hoeglund, L.; Skagius K.; Karlsson, F.; Smellie, J.

    1993-04-01

    This review has involved studies of natural analogues and natural geological systems leading to the identification and quantification of processes and features of importance to the performance and safety of repositories for radioactive waste. The features and processes selected for the study comprise general geochemical issues related to the performance of the near- and far-field, the performance and durability of construction materials and the effects of glaciation. For each of these areas a number of potentially important processes for repository performance have been described, and evidence for their existence, as well as quantification of parameters of models describing the processes have been sought from major natural analogue studies and site investigations. The review has aimed at covering a relatively broad range of issues at the expense of in-depth analysis. The quantitative data presented are in most cases compilations of data from the literature; in a few cases results of evaluations made within the current project are included

  12. PBDEs, PCBs, and DDE in eggs and their impacts on aplomado falcons (Falco femoralis) from Chihuahua and Veracruz, Mexico.

    Science.gov (United States)

    Mora, M A; Baxter, C; Sericano, J L; Montoya, A B; Gallardo, J C; Rodríguez-Salazar, J R

    2011-12-01

    Eggs from aplomado falcons (Falco femoralis septentrionalis) nesting in Chihuahua and Veracruz, Mexico, were analyzed for organochlorine pesticides, PCBs, and PBDEs. p,p'-DDE was the only organochlorine found in all eggs at concentrations ranging from 0.13 to 7.85 μg/g wet weight. PCBs ranged from 0.04 to 2.80 μg/g wet weight and PBDEs from 62 to 798 ng/g lipid weight. DDE concentrations in eggs were not significantly different among regions; however, PCBs were significantly greater (P = 0.015) in Tinaja Verde, Chihuahua than in the other three regions. Also, PBDEs were significantly higher (P Mexico. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Alligator Rivers analogue project

    International Nuclear Information System (INIS)

    Duerden, P.

    1990-01-01

    Australian Nuclear Science and Technology Organization has extensively evaluated uranium ore bodies in the Alligator Rivers Uranium Province in Australia as analogues of radioactive waste repositories. The work was extended for a three-year program as an international project based on the Koongarra uranium deposit and sponsored by the OECD Nuclear Energy Agency. The technical program comprises six major sub-projects involving modelling and experimental work: modelling of radionuclide migration; hydrogeology of the Koongarra uranium deposit; uranium/thorium series disequilibria studies; groundwater and colloid studies; fission product studies; transuranic nuclide studies; an outline of the technical programs and a summary of progress in the technical sub-projects is given. This is followed by a series of technical reports which briefly describe current research tasks, and which have been separately indexed

  14. Climate Analogues for agricultural impact projection and adaptation – a reliability test

    Directory of Open Access Journals (Sweden)

    Swen P.M. Bos

    2015-10-01

    Full Text Available The climate analogue approach is often considered a valuable tool for climate change impact projection and adaptation planning, especially for complex systems that cannot be modelled reliably. Important examples are smallholder farming systems using agroforestry or other mixed-cropping approaches. For the projected climate at a particular site of interest, the analogue approach identifies locations where the current climate is similar to these projected conditions. By comparing baseline-analogue site pairs, information on climate impacts and opportunities for adaptation can be obtained. However, the climate analogue approach is only meaningful, if climate is a dominant driver of differences between baseline and analogue site pairs. For a smallholder farming setting on Mt. Elgon in Kenya, we tested this requirement by comparing yield potentials of maize and coffee (obtained from the IIASA Global Agro-ecological Zones dataset among 50 close analogue sites for different future climate scenarios and models, and by comparing local ecological knowledge and farm characteristics for one baseline-analogue pair.Yield potentials among the 50 closest analogue locations varied strongly within all climate scenarios, hinting at factors other than climate as major drivers of what the analogue approach might interpret as climate effects. However, on average future climatic conditions seemed more favourable to maize and coffee cultivation than current conditions. The detailed site comparison revealed substantial differences between farms in important characteristics, such as farm size and presence of cash crops, casting doubt on the usefulness of the comparison for climate change analysis. Climatic constraints were similar between sites, so that no apparent lessons for adaptation could be derived. Pests and diseases were also similar, indicating that climate change may not lead to strong changes in biotic constraints at the baseline site in the near future. From

  15. A Short Term Analogue Memory

    DEFF Research Database (Denmark)

    Shah, Peter Jivan

    1992-01-01

    A short term analogue memory is described. It is based on a well-known sample-hold topology in which leakage currents have been minimized partly by circuit design and partly by layout techniques. Measurements on a test chip implemented in a standard 2.4 micron analogue CMOS process show a droop...

  16. Geochemistry of the thermal springs from Piedras de Lumbre Zone, Chihuahua, Mexico; Geoquimica de los manantiales termales de la zona de Piedras de Lumbre, Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Tello Hinojosa, Enrique [Gerencia de Proyectos Geotermoelectricos de la Comision Federal de Electricidad, Morelia (Mexico)

    1996-01-01

    Chemical analysis of water produced by 12 hot springs in the geothermal areas of Recubichi and Piedras de Lumbre, Chihuahua, Mexico were carried out in order to establish the geochemical characteristic of the groundwater and to know their interaction with deeper geothermal fluids. We made two sampling of water and gases in 1984 and 1995. The chemical composition of waters produced by the springs is of sulfate alkaline type. It was found, according to the Na:K:Mg relative content that most hot springs are located in the partial equilibrium zone, whereas the lowest temperature hot springs shift toward the groundwaters domain. The temperature estimated from gas geothermometry was 187 degrees celsius. It was found that the He has a deep origin, whereas the N{sub 2} is of atmospheric origin. Methane was not detected, suggesting that equilibria between gases and the liquid phase was reached at temperatures over 150 degrees celsius. The chemical compositions for the springs at Recubichi and Piedras de Lumbre zones are similar, so, it suggests that they have the same origin. The water quality of the springs for agricultural use, is classified between C2-S2 and C2-S3 types, that suggest that this water can be used for irrigation. The arsenic element was not detected and the concentration for the boron element is lower that 0.175 ppm. [Espanol] Los analisis quimicos de agua de 12 manantiales y 4 fumarolas de las zonas de Recubichi y Piedras de Lumbre, Chihuahua, Mexico fueron estudiados con el fin de conocer las caracteristicas geoquimicas del acuifero somero y su interaccion con fluidos geotermicos. Se realizaron 2 muestreos tanto de agua como de gases en 1984 y 1995. En ambos muestreos se encontro que la composicioon quimica del agua de todos los manantiales es del tipo sulfatado-sodico. De acuerdo con el contenido relativo de Na:K:Mg el agua de los manantiales mas calientes (93 grados celsius), se ubica en la zona de equilibrio parcial, mientras que en los de menor

  17. Geochemistry of the thermal springs from San Antonio El Bravo zone, Chihuahua, Mexico; Geoquimica de manantiales termales de la zona de San Antonio El Bravo, Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Tello Hinojosa, Enrique [Gerencia de Proyectos Geotermoelectricos de la Comision Federal de Electricidad, Morelia (Mexico)

    1996-05-01

    Isotopic and chemical analysis o water produced by 14 springs in the San Antonio El Bravo, Chihuahua, Mexico geothermal area, were carried out in order to establish the geochemical characteristics of the groundwater and to know their interaction with deeper geothermal fluids. We made two samplings of water and gases in 1984 and 1995. The chemical composition of waters produced by the springs in of sodium-bicarbonate-chloride type. It was found, according to the Na:K:Mg relative content, that most hot springs are located in the partial equilibrium zone, whereas the lowest temperature hot springs shift toward the groundwaters domain. The temperature estimated from gas geothermometry was 129 degrees celsius. The isotopic composition at Ojo Caliente and Infiernito springs presents enrichment in {delta}{sup 18}O, product rock-water interaction at high temperature. The Agua Roque spring is located in the line of meteoric waters. Analysis of metals was carried out too, the concentration of gold element is 0.09 mg/l in Ojo Caliente and Infiernito springs, whereas silver, aluminum and iron elements were not detected. The water quality of the springs for agricultural use, is classified between C2-S1, C3-S1, C3- S2, C4-S3 and C4-S4 types, that suggests that only the water from Agua Roque can be used for irrigation. The arsenic element was not detected but the concentration of the boron element is high for irrigation use (2.39 ppm). [Espanol] Los analisis quimicos e isotopicos de agua de 14 manantiales de la zona de San Antonio El Bravo. Chihuahua, Mexico, fueron realizados con el fin de conocer las caracteristicas geoquimicas del acuifero somero y su interaccion con fluidos geotermicos. Se realizaron 2 muestreos tanto de agua como de gases en 1984 y 1995. En ambos muestreos se encontro que la composicion quimica del agua de todos los manantiales es del tipo bicarbonatado-clorurado-sodico. De acuerdo con el contenido relativo de Na:K:Mg el agua de los manantiales mas calientes

  18. Crustal deformation and seismic measurements in the region of McDonald Observatory, West Texas. [Texas and Northern Chihuahua, Mexico

    Science.gov (United States)

    Dorman, H. J.

    1981-01-01

    The arrival times of regional and local earthquakes and located earthquakes in the Basin and Range province of Texas and in the adjacent areas of Chihuahua, Mexico from January 1976 to August 1980 at the UT'NASA seismic array are summarized. The August 1931 Texas earthquake is reevaluated and the seismicity and crustal structure of West Texas is examined. A table of seismic stations is included.

  19. Examiner's finger-mounted near-infrared spectroscopy is feasible to analyze cerebral and skeletal muscle oxygenation in conscious Chihuahuas

    Science.gov (United States)

    Hiwatashi, Keisuke; Doi, Kimiaki; Mizuno, Risuke; Yokosuka, Makoto

    2017-02-01

    To measure regional saturation of oxygen (rSO2) of hemoglobin and total hemoglobin index (HbI) in the brain (through the molera of the head) and skeletal muscle (musculus gracilis) of conscious Chihuahua dogs using an examiner's finger-mounted near-infrared spectroscopy (NIRS) device, Toccare, we investigated brain and skeletal muscle NIRS in 48 Chihuahuas without severe disease. To measure rSO2 and total HbI, a Toccare probe was placed on the molera of the head and musculus gracilis of each dog for real-time recording. Stable NIRS values were obtained within 10 s. We also examined the effect of anesthesia on rSO2 and total HbI of a Chihuahua. Cerebral rSO2 values (59%±7%) were significantly lower than those obtained at femoral regions (67%±6%), whereas total HbI values in the brain (0.38±0.09) were significantly higher than those of the musculus gracilis (0.20±0.05). Sedation with a combination of medetomidine and ketamine decreased cerebral rSO2 along with a corresponding reduction in heart rate. Sevoflurane anesthesia with 100% O2 maintained rSO2 in the brain with an even lower heart rate. In conclusions, we measured brain and skeletal muscle rSO2 of hemoglobin in conscious Chihuahuas using a newly developed NIRS device, Toccare, and found that changes in cerebral oxygenation levels were associated with administration of anesthetics.

  20. Comparison of Oil Content and Fatty Acids Profile of Western Schley, Wichita, and Native Pecan Nuts Cultured in Chihuahua, Mexico

    Directory of Open Access Journals (Sweden)

    L. R. Rivera-Rangel

    2018-01-01

    Full Text Available Two different extraction processes, Soxhlet and ultrasound, were used to obtain the oil extracts of Western Schley, Wichita, and Native pecan nuts cultured in Chihuahua, Mexico. The aspects evaluated in this study were the extraction yield of the processes and fatty acids’ profile of the resulting extracts. Gas chromatography coupled with mass spectrometry (GC-MS was used to identify and determine the composition percentage of fatty acids present in pecan nuts oils extracted. The results obtained show that higher oil extraction yields were obtained by Soxhlet method with hexane (69.90% in Wichita varieties. Wichita, Western Schley, and Native pecan nuts from Chihuahua are rich in PUFA (polyunsaturated fatty acids and MUFA (monounsaturated fatty acids and have low levels of SFA (saturated fatty acids. The predominant fatty acid present in all pecan nuts oils was linoleic acid followed by oleic acid. Myristic acid, palmitic acid, and linolenic acid were also identified in representative quantities. The results from this study suggest that there are statistically significant differences in the chemical composition of the pecan nuts oils extracted from the varieties cultured in Chihuahua, Mexico, and those cultivated in other regions of the world.

  1. Comparison of Oil Content and Fatty Acids Profile of Western Schley, Wichita, and Native Pecan Nuts Cultured in Chihuahua, Mexico

    Science.gov (United States)

    Rivera-Rangel, L. R.; Aguilera-Campos, K. I.; García-Triana, A.; Ayala-Soto, J. G.; Chavez-Flores, D.

    2018-01-01

    Two different extraction processes, Soxhlet and ultrasound, were used to obtain the oil extracts of Western Schley, Wichita, and Native pecan nuts cultured in Chihuahua, Mexico. The aspects evaluated in this study were the extraction yield of the processes and fatty acids' profile of the resulting extracts. Gas chromatography coupled with mass spectrometry (GC-MS) was used to identify and determine the composition percentage of fatty acids present in pecan nuts oils extracted. The results obtained show that higher oil extraction yields were obtained by Soxhlet method with hexane (69.90%) in Wichita varieties. Wichita, Western Schley, and Native pecan nuts from Chihuahua are rich in PUFA (polyunsaturated fatty acids) and MUFA (monounsaturated fatty acids) and have low levels of SFA (saturated fatty acids). The predominant fatty acid present in all pecan nuts oils was linoleic acid followed by oleic acid. Myristic acid, palmitic acid, and linolenic acid were also identified in representative quantities. The results from this study suggest that there are statistically significant differences in the chemical composition of the pecan nuts oils extracted from the varieties cultured in Chihuahua, Mexico, and those cultivated in other regions of the world. PMID:29610686

  2. Comparison of Oil Content and Fatty Acids Profile of Western Schley, Wichita, and Native Pecan Nuts Cultured in Chihuahua, Mexico.

    Science.gov (United States)

    Rivera-Rangel, L R; Aguilera-Campos, K I; García-Triana, A; Ayala-Soto, J G; Chavez-Flores, D; Hernández-Ochoa, L

    2018-01-01

    Two different extraction processes, Soxhlet and ultrasound, were used to obtain the oil extracts of Western Schley, Wichita, and Native pecan nuts cultured in Chihuahua, Mexico. The aspects evaluated in this study were the extraction yield of the processes and fatty acids' profile of the resulting extracts. Gas chromatography coupled with mass spectrometry (GC-MS) was used to identify and determine the composition percentage of fatty acids present in pecan nuts oils extracted. The results obtained show that higher oil extraction yields were obtained by Soxhlet method with hexane (69.90%) in Wichita varieties. Wichita, Western Schley, and Native pecan nuts from Chihuahua are rich in PUFA (polyunsaturated fatty acids) and MUFA (monounsaturated fatty acids) and have low levels of SFA (saturated fatty acids). The predominant fatty acid present in all pecan nuts oils was linoleic acid followed by oleic acid. Myristic acid, palmitic acid, and linolenic acid were also identified in representative quantities. The results from this study suggest that there are statistically significant differences in the chemical composition of the pecan nuts oils extracted from the varieties cultured in Chihuahua, Mexico, and those cultivated in other regions of the world.

  3. Aspects of radiological safety and protection in the decontamination of the Benefit plant of uranium in Ciudad Aldama and in the storage of its residues in Pena Blanca, Chihuahua, Mexico; Aspectos de seguridad y proteccion radiologica en la descontaminacion de la planta de beneficio de uranio en Ciudad Aldama y en el almacenamiento de sus residuos en Pena Blanca, Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Ruiz C, M A [Facultad de Quimica, UNAM (Mexico)

    1998-07-01

    Between 1969 and 1971 the National Commission of Nuclear Energy and the Mining Fostering Commission operated coordinately a production plant of uranium and molybdenum concentrates (Benefit plant) at Ciudad Aldama, Chihuahua, Mexico. During two years of operation some 45 tonnes of uranium concentrate and approximately 35,000 tonnes of uranium wetlands were produced. These last were stored in a dam to 120 m. toward West of the plant. Due to the nearness of the population with respect to what was the Benefit plant and over all to the wetland dam, the objective of this work had two main aspects: On the one hand, to carry out the works of radiological decontamination of the benefit plant of uranium, according to the established normative by the Regulatory organization in matter of radiological safety and protection (CNSNS) for the population and the hard workers. After that the works mentioned were realized it was considered that the estate which comprises what was the Benefit plant did not reach the established criteria by the CNSNS for being considered of unrestricted use such estate and it was not allowed any type of construction in the zone which could be showed the residual contamination which remains there. On the other hand, to determine the site where could be stored the radioactive wastes generated by the radiological decontamination and the wetland mobilization for its definitive storage in benefit of the present population and of the future generations due to the radionuclides which are in a such material. The site more adequate technical and economically to storage the wastes generated by this activity was evaluated. Whereby studies about demography, use of soil and water, meteorology, hydrology and ecology were realized. The site selected being in the Pena Blanca mountains, Chihuahua, place where is located one of the uranium zones and the most important of the country. In this work, specific objectives also were treated such as: knowing the radiological

  4. Application of natural analogues in the Yucca Mountain project - overview

    International Nuclear Information System (INIS)

    Simmons, Ardyth M.

    2003-01-01

    The Natural Analogue Synthesis Report (NASR) [1] provides a compilation of information from analogues that test, corroborate, and add confidence to process models and model predictions pertinent to total system performance assessment (TSPA). The report updated previous work [2] with new literature examples and results of quantitative studies conducted by the Yucca Mountain Project (YMP). The intent of the natural analogue studies was to collect corroborative evidence from analogues to demonstrate greater understanding of processes expected to occur during postclosure of a proposed Yucca Mountain repository. Natural analogues, as used here, refer to either natural or anthropogenic systems in which processes similar to those expected to occur in a nuclear waste repository are thought to have occurred over long time periods (decades to millenia) and large spatial scales (up to tens of kilometers). In the past, the YMP has used analogues for testing and building confidence in conceptual and numerical process models in a number of ways. Yucca Mountain mineral alteration phases provided a self-analogue for postclosure alteration [3]. Thermodynamic parameters for silica minerals of the Wairakai, New Zealand geothermal field were added to databases used in geochemical modeling [4]. Scoping calculations of radionuclide transport using the Yucca Mountain TSPA numerical model were conducted for the Peqa Blanca site [5]. Eruption parameters from the Cerro Negro volcano, Nicaragua, were used to verify codes that model ash plume dispersion [6]. Analogues have also been used in supplemental science and performance analyses to provide multiple lines of evidence in support of both analyses and model reports (AMRs) [7]; in screening arguments for inclusion or exclusion of features, events, and processes (FEP)s in TSPAs; in the quantification of uncertainties [7]; in expert elicitations of volcanic and seismic hazards [8, 9] and in peer reviews [10]. Natural analogues may be applied

  5. Stratigraphy of the PB-1 well, Nopal I uranium deposit, Sierra Pena Blanca, Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Dobson, P.; Fayek, M.; Goodell, P.; Ghezzehei, T.; Melchor, F.; Murrell, M.; Oliver, R.; Reyes-Cortes, I.A.; de la Garza, R.; Simmons, A.

    2008-08-01

    The Nopal I site in the Pena Blanca uranium district has a number of geologic and hydrologic similarities to the proposed high-level radioactive waste repository at Yucca Mountain, making it a useful analogue to evaluate process models for radionuclide transport. The PB-1 well was drilled in 2003 at the Nopal I uranium deposit as part of a DOE-sponsored natural analogue study to constrain processes affecting radionuclide transport. The well penetrates through the Tertiary volcanic section down to Cretaceous limestone and intersects the regional aquifer system. The well, drilled along the margin of the Nopal I ore body, was continuously cored to a depth of 250 m, thus providing an opportunity to document the local stratigraphy. Detailed observations of these units were afforded through petrographic description and rock-property measurements of the core, together with geophysical logs of the well. The uppermost unit encountered in the PB-1 well is the Nopal Formation, a densely welded, crystal-rich, rhyolitic ash-flow tuff. This cored section is highly altered and devitrified, with kaolinite, quartz, chlorite, and montmorillonite replacing feldspars and much of the groundmass. Breccia zones within the tuff contain fracture fillings of hematite, limonite, goethite, jarosite, and opal. A zone of intense clay alteration encountered in the depth interval 17.45-22.30 m was interpreted to represent the basal vitrophyre of this unit. Underlying the Nopal Formation is the Coloradas Formation, which consists of a welded lithic-rich rhyolitic ash-flow tuff. The cored section of this unit has undergone devitrification and oxidation, and has a similar alteration mineralogy to that observed in the Nopal tuff. A sharp contact between the Coloradas tuff and the underlying Pozos Formation was observed at a depth of 136.38 m. The Pozos Formation consists of poorly sorted conglomerate containing clasts of subangular to subrounded fragments of volcanic rocks, limestone, and chert

  6. Stratigraphy of the PB-1 well, Nopal I uranium deposit, Sierra Pena Blanca, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Dobson, P.; Fayek, M.; Goodell, P.; Ghezzehei, T.; Melchor, F.; Murrell, M.; Oliver, R.; Reyes-Cortes, I.A.; de la Garza, R.; Simmons, A.

    2008-01-01

    The Nopal I site in the Pena Blanca uranium district has a number of geologic and hydrologic similarities to the proposed high-level radioactive waste repository at Yucca Mountain, making it a useful analogue to evaluate process models for radionuclide transport. The PB-1 well was drilled in 2003 at the Nopal I uranium deposit as part of a DOE-sponsored natural analogue study to constrain processes affecting radionuclide transport. The well penetrates through the Tertiary volcanic section down to Cretaceous limestone and intersects the regional aquifer system. The well, drilled along the margin of the Nopal I ore body, was continuously cored to a depth of 250 m, thus providing an opportunity to document the local stratigraphy. Detailed observations of these units were afforded through petrographic description and rock-property measurements of the core, together with geophysical logs of the well. The uppermost unit encountered in the PB-1 well is the Nopal Formation, a densely welded, crystal-rich, rhyolitic ash-flow tuff. This cored section is highly altered and devitrified, with kaolinite, quartz, chlorite, and montmorillonite replacing feldspars and much of the groundmass. Breccia zones within the tuff contain fracture fillings of hematite, limonite, goethite, jarosite, and opal. A zone of intense clay alteration encountered in the depth interval 17.45-22.30 m was interpreted to represent the basal vitrophyre of this unit. Underlying the Nopal Formation is the Coloradas Formation, which consists of a welded lithic-rich rhyolitic ash-flow tuff. The cored section of this unit has undergone devitrification and oxidation, and has a similar alteration mineralogy to that observed in the Nopal tuff. A sharp contact between the Coloradas tuff and the underlying Pozos Formation was observed at a depth of 136.38 m. The Pozos Formation consists of poorly sorted conglomerate containing clasts of subangular to subrounded fragments of volcanic rocks, limestone, and chert

  7. Knowledge and use of edible mushrooms in two municipalities of the Sierra Tarahumara, Chihuahua, Mexico.

    Science.gov (United States)

    Quiñónez-Martínez, Miroslava; Ruan-Soto, Felipe; Aguilar-Moreno, Ivonne Estela; Garza-Ocañas, Fortunato; Lebgue-Keleng, Toutcha; Lavín-Murcio, Pablo Antonio; Enríquez-Anchondo, Irma Delia

    2014-09-17

    The Sierra Madre Occidental of Chihuahua in Northern Mexico is inhabited by indigenous Raramuris, mestizos, and other ethnic groups. The territory consists of canyons and ravines with pine, oak and pine-oak forests in the higher plateaus. A great diversity of potentially edible mushrooms is found in forests of the Municipalities of Bocoyna and Urique. Their residents are the only consumers of wild mushrooms in the Northern Mexico; they have a long tradition of collecting and eating these during the "rainy season." However, despite the wide diversity of edible mushrooms that grow in these areas, residents have a selective preference. This paper aims to record evidence of the knowledge and use of wild potentially edible mushroom species by inhabitants of towns in the Sierra Tarahumara of Chihuahua, Mexico. Using a semi-structured technique, we surveyed 197 habitants from seven locations in Urique, Bocoyna, and the Cusarare area from 2010 to 2012. Known fungi, local nomenclature, species consumed, preparation methods, appreciation of taste, forms of preservation, criteria for differentiating toxic and edible fungi, other uses, economic aspects, and traditional teaching were recorded. To identify the recognized species, photographic stimuli of 22 local edible species and two toxic species were used. The respondents reported preference for five species: Amanita rubescens, Agaricus campestris, Ustilago maydis, Hypomyces lactifluorum, and the Amanita caesarea complex. No apparent differences were found between ethnic groups in terms of preference, although mestizos used other species in Bocoyna (Boletus edulis and B. pinophilus). Some different uses of fungi are recognized by respondents, i.e. home decorations, medicine, as food in breeding rams, etc. The studied population shows a great appreciation towards five species, mainly the A. caesarea complex, and an apparent lack of knowledge of nearly 20 species which are used as food in other areas of Mexico. There are no

  8. [Epidemiology of gunshot wounds at Ciudad Juárez, Chihuahua General Hospital].

    Science.gov (United States)

    Moye-Elizalde, G A; Ruiz-Martínez, F; Suarez-Santamaría, J J; Ruiz-Ramírez, M; Reyes-Gallardo, A; Díaz-Apodaca, B A

    2013-01-01

    Since 2007, Ciudad Juárez, Chihuahua has been considered as one of the most violent cities in the world. The General Hospital in this city is the main facility where patients with gunshot wounds are taken. The increased number of admissions of patients with these injuries to many hospitals in the country deserves special attention, as it has an impact on hospital resources and management protocols. To disseminate the epidemiology of fractures caused by gunshot wounds and the hospital care of these patients. A retrospective, observational cohort study was conducted of patients admitted to the Traumatology and Orthopedics Service, Cd. Juárez General Hospital, in Chihuahua, Mexico, from January 2008 to December 2010. All of them sustained fractures resulting from gunshot wounds. A total of 1281 patients with a diagnosis of gunshot wounds were admitted to the hospital; 402 of them were included in this study with 559 fractures; 329 were males and 73 females. Of the 559 fractures, 257 involved the upper limb, 294 the lower limb, and 8 the pelvis. Gunshot wounds-related fractures were classified according to the Gustilo classification. Seventy-nine patients had grade I fractures, 302 grade III, and 21 patients had both grades. Conservative treatment was used in 44.3% of fractures and osteosynthesis in 55%. One patient underwent amputation upon admission. The most widely used osteosynthesis methods were external fixator (37%), straight plates (21%) and intramedullary nail (17%). Five patients (1.3%) underwent amputation: two with femur fracture and 3 with humeral fracture. There were 27 deep infections (6%); one of them resulted in late amputation of the pelvic limb. The most common associated injuries included: chest injuries in 20 patients and abdominal injuries in 17. The range of hospital stay was 1-18 days, with a mean stay of 11 days. The overall mortality rate considering the total number of patients admitted (1,281) was 99 patients (7.72%). From 2006 to 2010 the

  9. Chemopreventive properties of curcumin analogues ...

    African Journals Online (AJOL)

    Chemopreventive properties of curcumin analogues, ... These compounds .... using microscope with 400 × magnification. APC ... Figure 3: Microscopic images of rat colorectal tissue stained with APC rabbit polyclonal antibody with different.

  10. GAMMA-RAY CHARACTERIZATION OF THE U-SERIES INTERMEDIATE DAUGHTERS FROM SOIL SAMPLES AT THE PENA BLANCA NATURAL ANALOG, CHIHUAHUA, MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    D.C. French; E.Y. Anthony; P.C. Goodell

    2005-07-18

    The Pena Blanca natural analog is located in the Sierra Pena Blanca, approximately 50 miles north of Chihuahua City, Mexico. The Sierra Pena Blanca is composed mainly of ash-flow tuffs, and the uranium in the region is contained in the brecciated zones of these tuffs. The Pena Blanca site is considered a natural analog to the proposed Yucca Mountain Nuclear Waste Repository because they share similar characteristics of structure, volcanic lithology, tectonic activity, and hydrologic regime. One of the mineralized zones, the Nopal I deposit, was mined in the early 1980s and the ore was stockpiled close to the mine. This stockpile area has subsequently been cleared and is referred to as the prior high-grade stockpile (PHGS) site. Soil surrounding boulders of high-grade ore associated with the PHGS site have been sampled. The purpose of this study is to characterize the transport of uranium series radioisotopes from the boulder to the soil during the past 25 years. Transport is characterized by determining the activities of individual radionuclides and daughter to parent ratios. The daughter to parent ratios are used to establish whether the samples are in secular equilibrium. Activities are determined using gamma-ray spectroscopy. Isotopes of the uranium series decay chain detected by gamma-ray spectroscopy include {sup 210}Pb, {sup 234}U, {sup 234}Th, {sup 230}Th, {sup 226}Ra, {sup 214}Pb, {sup 214}Bi, and {sup 234}Pa. Preliminary results indicate that some daughter to parent pairs appear to be in secular disequilibrium. Thorium is in excess relative to uranium, and radium is in excess relative to thorium. A deficiency appears to exist for {sup 210}Pb relative to {sup 214}Bi and {sup 214}Pb. If these results are borne out by further analysis, they would suggest transport of nuclides from the high-grade boulder into its surroundings, followed by continued leaching of uranium and lead from the environment.

  11. GAMMA-RAY CHARACTERIZATION OF THE U-SERIES INTERMEDIATE DAUGHTERS FROM SOIL SAMPLES AT THE PENA BLANCA NATURAL ANALOG, CHIHUAHUA, MEXICO

    International Nuclear Information System (INIS)

    French, D.C.; Anthony, E.Y.; Goodell, P.C.

    2005-01-01

    The Pena Blanca natural analog is located in the Sierra Pena Blanca, approximately 50 miles north of Chihuahua City, Mexico. The Sierra Pena Blanca is composed mainly of ash-flow tuffs, and the uranium in the region is contained in the brecciated zones of these tuffs. The Pena Blanca site is considered a natural analog to the proposed Yucca Mountain Nuclear Waste Repository because they share similar characteristics of structure, volcanic lithology, tectonic activity, and hydrologic regime. One of the mineralized zones, the Nopal I deposit, was mined in the early 1980s and the ore was stockpiled close to the mine. This stockpile area has subsequently been cleared and is referred to as the prior high-grade stockpile (PHGS) site. Soil surrounding boulders of high-grade ore associated with the PHGS site have been sampled. The purpose of this study is to characterize the transport of uranium series radioisotopes from the boulder to the soil during the past 25 years. Transport is characterized by determining the activities of individual radionuclides and daughter to parent ratios. The daughter to parent ratios are used to establish whether the samples are in secular equilibrium. Activities are determined using gamma-ray spectroscopy. Isotopes of the uranium series decay chain detected by gamma-ray spectroscopy include 210 Pb, 234 U, 234 Th, 230 Th, 226 Ra, 214 Pb, 214 Bi, and 234 Pa. Preliminary results indicate that some daughter to parent pairs appear to be in secular disequilibrium. Thorium is in excess relative to uranium, and radium is in excess relative to thorium. A deficiency appears to exist for 210 Pb relative to 214 Bi and 214 Pb. If these results are borne out by further analysis, they would suggest transport of nuclides from the high-grade boulder into its surroundings, followed by continued leaching of uranium and lead from the environment

  12. Investigation of the radioactivity in air, water and soil in the Estado de Chihuahua

    International Nuclear Information System (INIS)

    Montero C, M.E.; Renteria V, M.; Herrera P, E.F.; Villalba, M.L.; Colmenero S, L.H.

    2004-01-01

    The results of the determinations of activities of the series of U-238, Th-232 and the K-40 in soils, of the Rn-222 in the air of the domiciles, and in underground water are presented, as well as the total uranium activity in underground water, product of an extensive sampling in the state of Chihuahua. In two of the aquifers a positive correlation was obtained among the concentration of total uranium and the Rn-222 dissolved in the water of each well. Also it was finds a positive tendency among the averages of the concentration of U-238 in the soil and of the concentration of Rn-222 in the air of the domiciles in different towns, and among the averages of the concentration of U-238 in the floor and of the concentration of the Rn-222 dissolved in the well water in different aquifer. It is suggested that the constitution for rocks more or less uraniferous of the alluvial valleys gives explanation to the observed correlations. (Author)

  13. Establishment of Native Grasses with Biosolids on Abandoned Croplands in Chihuahua, Mexico

    Directory of Open Access Journals (Sweden)

    Pedro Jurado-Guerra

    2013-01-01

    Full Text Available The objective of the work was to evaluate establishment and forage production of native grasses with application of biosolids, a byproduct of waste-water treatment, at an abandoned field, in Ejido Nuevo Delicias, Chihuahua, Mexico. Four biosolids rates from 0 (control to 30 dry Mg ha−1 and two methods of application, surface applied (BioSur and soil incorporated (BioInc, were evaluated. Seedbed preparation included plowing and harrowing before rainfall. Field plots of 5 × 5 m were manually sown with a mix of blue grama (Bouteloua gracilis (50% and green sprangletop (Leptochloa dubia (50% in early August 2005. Experimental design was a randomized block with a split plot arrangement. Grass density, height, and forage production were estimated for three years. Data were analyzed with mixed linear models and repeated measures. Green sprangletop density increased under all biosolids rates regardless of method of application, while blue grama density slightly decreased. Biosolids were more beneficial for green sprangletop height than for blue grama height. Blue grama forage production slightly increased, while green sprangletop forage production increased the most at 10 Mg ha−1 biosolids rate under BioSur method. It was concluded that BioSur application at 10 and 20 Mg ha−1 rates had positive effects on the establishment and forage production of native grasses, especially green sprangletop.

  14. Migration behavior of naturally occurring radionuclides at the Nopal I uranium deposit, Chihuahua, Mexico

    Science.gov (United States)

    Prikryl, James D.; Pickett, David A.; Murphy, William M.; Pearcy, English C.

    1997-04-01

    Oxidation of pyrite at the Nopal I uranium deposit, Peña Blanca district, Chihuahua, Mexico has resulted in the formation of Fe-oxides/hydroxides. Anomalous U concentrations (i.e. several hundred to several thousand ppm) measured in goethite, hematite, and amorphous Fe-oxyhydroxides in a major fracture that crosscuts the deposit and the absence of U minerals in the fracture suggest that U was retained during secondary mineral growth or sorbed on mineral surfaces. Mobilization and transport of U away from the deposit is suggested by decreasing U concentrations in fracture-infilling materials and in goethite and hematite with distance from the deposit. Greater than unity {234U}/{238U} activity ratios measured in fracture-infilling materials indicate relatively recent ( < 1 Ma) U uptake from fluids that carried excess 234U. Systematic decreases in {234U}/{238U} activity ratios of fracture materials with distance from the deposit suggest a multistage mobilization process, such as remobilization of U from 234U-enriched infill minerals or differential or diminished transport of U-bearing solutions containing excess 234U.

  15. Uranium deposits associated to tertiary acid volcanism of the Pena Blanca Sierra (Chihuahua, Mexico)

    International Nuclear Information System (INIS)

    Aniel, B.

    1986-12-01

    The uraniferous deposits located in the Sierra de Pena Blanca (Chihuahua, Mexico) are the consequence of successive events that modified acid volcanic rocks. The devitrification of the Nopal Formation, vitroclastic tuffs, is esential in the cooling history because it releases uranium that becomes available. The uranium present in fluids as uranylcarbonate complexes, precipitate along the lamellea of hematite (exsolutions of the ilmenites). The presence of sulfur causes the destabilization of the ilmenites with uranium oxide (pitchblende - titanium oxide - pyrite), the pseudomorph of magnetites (pitchblende - pyrite) and the transformation of hematite into pyrite. The silice coming from the kaolinization of feldspars recristallizes as microcristalline quartz so that the rock appears compact. Fractures cause the uplifting of the lower unit of Nopal formation. It has been altered to montmorillonite. A carbonatation of this tuff has been observed and these two types of alteration occur after kaolinization. The Escuadra formation overlies the Nopal formation. The deposition takes place on an eroded basement where a soil developed. The two formations will together undergo transformations due to the saturation level and the primary ore will be only oxidized or oxidized, transported and reconcentrated. Late and localized thermal activities have been observed and may be the result of tectonic movements occurring after the supergene modification [fr

  16. Neuronal ceroid-lipofuscinosis in longhaired Chihuahuas: clinical, pathologic, and MRI findings.

    Science.gov (United States)

    Nakamoto, Yuya; Yamato, Osamu; Uchida, Kazuyuki; Nibe, Kazumi; Tamura, Shinji; Ozawa, Tsuyoshi; Ueoka, Naotami; Nukaya, Aya; Yabuki, Akira; Nakaichi, Munekazu

    2011-01-01

    Neuronal ceroid-lipofuscinosis (NCL) is a rare group of inherited neurodegenerative lysosomal storage diseases characterized histopathologically by the abnormal accumulation of ceroid- or lipofuscin-like lipopigments in neurons and other cells throughout the body. The present article describes the clinical, pathologic, and magnetic resonance imaging (MRI) findings of the NCL in three longhaired Chihuahuas between 16 mo and 24 mo of age. Clinical signs, including visual defects and behavioral abnormalities, started between 16 mo and 18 mo of age. Cranial MRI findings in all the dogs were characterized by diffuse severe dilation of the cerebral sulci, dilated fissures of diencephalons, midbrain, and cerebellum, and lateral ventricular enlargement, suggesting atrophy of the forebrain. As the most unusual feature, diffuse meningeal thickening was observed over the entire cerebrum, which was strongly enhanced on contrast T1-weighted images. The dogs' conditions progressed until they each died subsequent to continued neurologic deterioration between 23 mo and 24 mo of age. Histopathologically, there was severe to moderate neuronal cell loss with diffuse astrogliosis throughout the brain. The remaining neuronal cells showed intracytoplasmic accumulation of pale to slightly yellow lipopigments mimicking ceroid or lipofuscin. The thickened meninges consisted of the proliferation of connective tissues with abundant collagen fibers and mild infiltration of inflammatory cells suggesting neuroimmune hyperactivity. Although the etiology of this neuroimmune hyperactivity is not currently known, MRI findings such as meningeal thickening may be a useful diagnostic marker of this variant form of canine NCL.

  17. Desarrollo forestal sustentable en Chihuahua, México: una estrategia multidimensional

    Directory of Open Access Journals (Sweden)

    Concepción Luján Álvarez

    2008-01-01

    Full Text Available Establecer una estrategia multidimensional para lograr el desarrollo forestal sustentable en la región de clima templado frío en Chihuahua, México, fue el objetivo del presente estudio, que se obtuvo con la aplicación del modelo Multiconferencia de Búsqueda (MCB, basado en el sistema de organización por asociaciones de productores forestales (ejidatarios, comuneros y pequeños propietarios, incluidos indígenas y mestizos. La metodología participativa aplicada consideró el carácter social de la propiedad de los recursos forestales en México, y se apoyó en la colaboración activa de ejidos y comunidades y demás actores relacionados. La estrategia multidimensional establecida está integrada por las dimensiones ecológicas ambientales, socioculturales, económicas, político-institucionales y científico-tecnológicas, que incluye objetivos y acciones estratégicas que consideran las necesidades e intereses comunes de los involucrados en la búsqueda del desarrollo forestal regional, con visión de sustentabilidad.

  18. The Social Construction of Transgenic Corn: Relevant Social Actors in Chihuahua

    Directory of Open Access Journals (Sweden)

    Marco Antonio Fernández Nava

    2016-01-01

    Full Text Available According to the socio-technical perspective, the meaning of a technological artefact does not lie within the artefact itself. Analyzing transgenic corn from a socio-technical perspective means taking one’s research beyond the artefact itself. To do this, it is necessary to overcome and avoid determinist positions, be they social or technological. This work takes as it point of departure the Social Construction of Technology Focus (SCOT. In this sense, transgenic corn is an unfinished object that is affected by an onslaught of struggles, opinions, agreements, disagreements, designs and redefinitions of the relevant social actors. These groups, the Democratic Campesino Front, El Barzón, National Agro-dynamic and Regional Agricultural Union of Yellow Corn Producers (UNIPRO, demonstrate how technological development is a social process. The deconstruction of transgenic corn according to the perspectives of these different social actors is key to the process of constructivist analysis: to take the artefacts just as each social actor views them. The objective of this study then is to describe how the different social groups, through their actions, construct and deconstruct the meaning of transgenic corn in Chihuahua, Mexico.

  19. Uranium and radium activities in samples of aquifers of the main cities of the Estado de Chihuahua; Actividades de uranio y radio en muestras de agua subterranea de las principales ciudades del Estado de Chihuahua

    Energy Technology Data Exchange (ETDEWEB)

    Villalba, L.; Colmenero S, L.; Montero C, M.E. [CIMAV, Av. Miguel de Cervantes Saavedra 120, 31109 Chihuahua (Mexico)]. e-mail: lourdes.villalba@cimav.edu.mx

    2003-07-01

    The natural uranium is in four valence states +3, +4, +5 and +6 being the hexavalent state the more soluble, which plays an important role in the transport of the uranium in the environment. The high concentrations of uranium in water not only in near waters to uranium mines, but also are in some mineral waters or in waters that are extracted of deep wells as it happens in the State of Chihuahua, where the underground waters are the fundamental source of consumption. The radium is a disintegration product of the uranium, the radio content in water is considered the second source of natural radioactivity. The distribution of radium in water is in function of the uranium content present in the aquifer. It was determined the uranium and radium content in samples of underground water of the main cities of the State of Chihuahua according to their number of inhabitants. The extraction methods for uranium and sulfates precipitation of Ba-Ra by means of the addition of barium carriers for the radium were used. The measures of the activities of uranium and radium were carried out by means of a portable liquid scintillation detector trade mark Thiathler-OY HIDEX. The obtained results have demonstrated that the content of uranium and radium in dissolution are in most of the sampling wells above the permissible maximum levels that manage the Mexican regulations. The high contents of uranium and radio can be attributed since to the influence of the geologic substrate characteristic of the zone in the State of Chihuahua they exist but of 50 uranium deposits. (Author)

  20. Oral folic acid supplementation decreases palate and/or lip cleft occurrence in Pug and Chihuahua puppies and elevates folic acid blood levels in pregnant bitches.

    Science.gov (United States)

    Domosławska, A; Jurczak, A; Janowski, T

    2013-01-01

    The aim of this study was to compare the frequency of the occurrence of lip and/or palate cleft (CL/CP) in new-borns of two breeds, Pugs and Chihuahuas, and to measure the folic acid blood levels in bitches during gestations both with and without folic acid oral supplementation. Bitches of 13 Pugs and 17 Chihuahuas with CL/CP cases were used in the study. In trial 1, the animals of the experimental group (n=25) were given additional folic acid from the onset of heat till the 40th day of gestation. The females of the control group (n=12) were fed a traditional diet. From all the animals blood was collected at the onset of heat, 14 days later and on the 30th day of the gestation to estimate folic acid concentration. In trial 2, the prevalence of CP/CL cases in litters from pregnancies before and after supplementation was compared. The percentage of puppies with CL/CP after supplementation decreased in both Pugs and Chihuahua puppies (10.86% and 15.78% vs. 4.76% and 4.8% respectively). On Day 0, the concentrations of folic acid were at a low physiological level (around 8 ng/ml) in all the animals. In bitches of the experimental group the blood level of folic acid on day 14th and 30th of the treatment showed an increase in both breeds (13.65 +/- 4.27 ng/ml in Pugs, 10.79 +/- 2.84 ng/ml in Chihuahuas, and 14.94 +/- 3.22 ng/ml in Pugs, 12.95 +/- 3.58 in Chihuahuas, respectively) while in the control group, this level decreased with time of gestation both in Pugs and in Chihuahuas (around 6 ng/ml). Folic acid supplementation seems to be a simple, effective preventive method to reduce the risk of CL/CP, especially in the predisposed breeds.

  1. Applications of natural analogue studies to Yucca Mountain as a potential high level radioactive waste repository

    International Nuclear Information System (INIS)

    1995-02-01

    The 5-member group convened in Las Vegas, Nov. 11-13, 1991, to clarify the extent to which studies of natural analogues can assist the Yucca Mountain site characterization (SC) project. This document is to provide guidance and recommendations to DOE for the implementation of natural analogue studies in the SC program. Performance assessment, integrity of engineered barriers, and communication to the public and the scientific community are stressed. The reference design being developed by Babcock ampersand Wilcox Fuel Company are reviewed. Guidelines for selecting natural analogues are given. Quality assurance is discussed. Recommendations are given for developing an effective natural analogue program within the SC program

  2. PBDEs, PCBs, and DDE in eggs and their impacts on aplomado falcons (Falco femoralis) from Chihuahua and Veracruz, Mexico

    International Nuclear Information System (INIS)

    Mora, M.A.; Baxter, C.; Sericano, J.L.; Montoya, A.B.; Gallardo, J.C.; Rodriguez-Salazar, J.R.

    2011-01-01

    Eggs from aplomado falcons (Falco femoralis septentrionalis) nesting in Chihuahua and Veracruz, Mexico, were analyzed for organochlorine pesticides, PCBs, and PBDEs. p,p'-DDE was the only organochlorine found in all eggs at concentrations ranging from 0.13 to 7.85 μg/g wet weight. PCBs ranged from 0.04 to 2.80 μg/g wet weight and PBDEs from 62 to 798 ng/g lipid weight. DDE concentrations in eggs were not significantly different among regions; however, PCBs were significantly greater (P = 0.015) in Tinaja Verde, Chihuahua than in the other three regions. Also, PBDEs were significantly higher (P < 0.0001) in eggs from Veracruz than in those from Chihuahua. DDE concentrations in eggs were much lower than those associated with eggshell thinning. PBDEs and PCBs were lower than those reported in raptors from industrialized countries. Overall, contaminant concentrations observed suggest no likely impact on hatching success. The PBDE concentrations are among the first to be reported in raptor species in Mexico. - Highlights: → We analyzed environmental contaminants in eggs of aplomado falcons from Mexico. → Of all the organochlorine pesticides, only p,p'-DDE was detected in all the eggs. → Eggshell thickness was 20% thicker than the reported in eggshells from the 1970s. → Total PCBs and PBDEs were lower than those reported in industrialized countries. → Aplomado falcons in Mexico are currently not affected by DDE, PCBs, or PBDEs. - PBDEs, PCBs, and p,p'-DDE were not elevated in eggs and not likely to impact aplomado falcons in eastern and northern Mexico.

  3. Uranium and radium activities in samples of aquifers of the main cities of the Estado de Chihuahua

    International Nuclear Information System (INIS)

    Villalba, L.; Colmenero S, L.; Montero C, M.E.

    2003-01-01

    The natural uranium is in four valence states +3, +4, +5 and +6 being the hexavalent state the more soluble, which plays an important role in the transport of the uranium in the environment. The high concentrations of uranium in water not only in near waters to uranium mines, but also are in some mineral waters or in waters that are extracted of deep wells as it happens in the State of Chihuahua, where the underground waters are the fundamental source of consumption. The radium is a disintegration product of the uranium, the radio content in water is considered the second source of natural radioactivity. The distribution of radium in water is in function of the uranium content present in the aquifer. It was determined the uranium and radium content in samples of underground water of the main cities of the State of Chihuahua according to their number of inhabitants. The extraction methods for uranium and sulfates precipitation of Ba-Ra by means of the addition of barium carriers for the radium were used. The measures of the activities of uranium and radium were carried out by means of a portable liquid scintillation detector trade mark Thiathler-OY HIDEX. The obtained results have demonstrated that the content of uranium and radium in dissolution are in most of the sampling wells above the permissible maximum levels that manage the Mexican regulations. The high contents of uranium and radio can be attributed since to the influence of the geologic substrate characteristic of the zone in the State of Chihuahua they exist but of 50 uranium deposits. (Author)

  4. PBDEs, PCBs, and DDE in eggs and their impacts on aplomado falcons (Falco femoralis) from Chihuahua and Veracruz, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Mora, M.A., E-mail: mmora@tamu.edu [Department of Wildlife and Fisheries Sciences, Texas A and M University, College Station, TX 77843-2258 (United States); Baxter, C. [Department of Wildlife and Fisheries Sciences, Texas A and M University, College Station, TX 77843-2258 (United States); Sericano, J.L. [Geochemical and Environmental Research Group, Texas A and M University, College Station, TX 77845 (United States); Montoya, A.B. [The Peregrine Fund, Inc, Boise, ID 83709 (United States); Gallardo, J.C. [Instituto de Neuroetologia, Universidad Veracruzana, Xalapa, Veracruz 91190 (Mexico); Rodriguez-Salazar, J.R. [The Peregrine Fund, Inc, Boise, ID 83709 (United States)

    2011-12-15

    Eggs from aplomado falcons (Falco femoralis septentrionalis) nesting in Chihuahua and Veracruz, Mexico, were analyzed for organochlorine pesticides, PCBs, and PBDEs. p,p'-DDE was the only organochlorine found in all eggs at concentrations ranging from 0.13 to 7.85 {mu}g/g wet weight. PCBs ranged from 0.04 to 2.80 {mu}g/g wet weight and PBDEs from 62 to 798 ng/g lipid weight. DDE concentrations in eggs were not significantly different among regions; however, PCBs were significantly greater (P = 0.015) in Tinaja Verde, Chihuahua than in the other three regions. Also, PBDEs were significantly higher (P < 0.0001) in eggs from Veracruz than in those from Chihuahua. DDE concentrations in eggs were much lower than those associated with eggshell thinning. PBDEs and PCBs were lower than those reported in raptors from industrialized countries. Overall, contaminant concentrations observed suggest no likely impact on hatching success. The PBDE concentrations are among the first to be reported in raptor species in Mexico. - Highlights: > We analyzed environmental contaminants in eggs of aplomado falcons from Mexico. > Of all the organochlorine pesticides, only p,p'-DDE was detected in all the eggs. > Eggshell thickness was 20% thicker than the reported in eggshells from the 1970s. > Total PCBs and PBDEs were lower than those reported in industrialized countries. > Aplomado falcons in Mexico are currently not affected by DDE, PCBs, or PBDEs. - PBDEs, PCBs, and p,p'-DDE were not elevated in eggs and not likely to impact aplomado falcons in eastern and northern Mexico.

  5. La violencia en la región noroeste de Chihuahua. Experiencias e impactos desde la comunidad educativa

    OpenAIRE

    Marcos J. Estrada Ruiz; Adán Cano Aguilar

    2013-01-01

    La violencia escolar ha sido un tema explorado de manera importante en los últimos años desde la investigación educativa en México, sin embargo, en contextos de alta violencia no se han mostrado los impactos de la violencia extraescolar y estructural, en la escuela y en otros espacios comunitarios. El artículo presenta resultados de una investigación que tuvo por objetivo reconstruir el impacto de la violencia en la región noroeste de Chihuahua, desde la comunidad educativa (docentes, padres,...

  6. Introduction to electronic analogue computers

    CERN Document Server

    Wass, C A A

    1965-01-01

    Introduction to Electronic Analogue Computers, Second Revised Edition is based on the ideas and experience of a group of workers at the Royal Aircraft Establishment, Farnborough, Hants. This edition is almost entirely the work of Mr. K. C. Garner, of the College of Aeronautics, Cranfield. As various advances have been made in the technology involving electronic analogue computers, this book presents discussions on the said progress, including some acquaintance with the capabilities of electronic circuits and equipment. This text also provides a mathematical background including simple differen

  7. Severely impaired bone material quality in Chihuahua zebrafish resembles classical dominant human osteogenesis imperfecta.

    Science.gov (United States)

    Fiedler, Imke A K; Schmidt, Felix N; Wölfel, Eva M; Plumeyer, Christine; Milovanovic, Petar; Gioia, Roberta; Tonelli, Francesca; Bale, Hrishikesh A; Jähn, Katharina; Besio, Roberta; Forlino, Antonella; Busse, Björn

    2018-04-17

    Excessive skeletal deformations and brittle fractures in the vast majority of patients suffering from osteogenesis imperfecta (OI) are a result of substantially reduced bone quality. Since the mechanical competence of bone is dependent on the tissue characteristics at small length scales, it is of crucial importance to assess how osteogenesis imperfecta manifests at the micro- and nanoscale of bone. In this context, the Chihuahua (Chi/ +) zebrafish, carrying a heterozygous glycine substitution in the α1 chain of collagen type I, has recently been proposed as suitable animal model of classical dominant OI, showing skeletal deformities, altered mineralization patterns and a smaller body size. This study assessed the bone quality properties of Chi/+ at multiple length scales using micro-computed tomography (micro-CT), histomorphometry, quantitative back-scattered electron imaging, Fourier transform infrared spectroscopy, nanoindentation and X-ray microscopy. At the skeletal level, Chi/+ display smaller body size, deformities and fracture calli in the ribs. Morphological changes at the whole bone level showed that the vertebrae in Chi/+ had a smaller size, smaller thickness and distorted shape. At the tissue level, Chi/+ displayed a higher degree of mineralization, lower collagen maturity, lower mineral maturity, altered osteoblast morphology, and lower osteocyte lacunar density compared to WT. The alterations in the cellular, compositional and structural properties of Chi/+ bones bear an explanation for the impaired local mechanical properties, which promote an increase in overall bone fragility in Chi/ +. The quantitative assessment of bone quality in Chi/+ thus further validates this mutant as an important model reflecting osseous characteristics associated with human classical dominant osteogenesis imperfecta. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  8. The Greenland analogue project. Yearly report 2010

    Energy Technology Data Exchange (ETDEWEB)

    Harper, J; Brinkerhoff, D; Johnson, J [University of Montana, Missoula (United States); Ruskeeniemi, T; Engstroem, J; Kukkonen, I [Geological Survey of Finland (Finland); and others

    2012-04-15

    A four-year field and modelling study of the Greenland ice sheet and subsurface conditions, Greenland Analogue Project (GAP), has been initiated collaboratively by SKB, Posiva and NWMO to advance the understanding of processes associated with glaciation and their impact on the long-term performance of a deep geological repository. The study site encompasses a land terminus portion of the Greenland ice sheet, east of Kangerlussuaq, and is in many ways considered to be an appropriate analogue of the conditions that are expected to prevail in much of Canada and Fennoscandia during future glacial cycles. The project begins in 2009 and is scheduled for completion in 2012. Our current understanding of the hydrological, hydrogeological and hydrogeochemical processes associated with cold climate conditions and glacial cycles, and their impact on the long-term performance of deep geological repositories for spent nuclear fuel, will be significantly improved by studying a modern analogue. The GAP will conduct the first in situ investigations of some of the parameters and processes needed to achieve a better understanding of how an ice sheet may impact a deep repository, and will provide measurements, observations and data that may significantly improve our safety assessments and risk analyses of glaciation scenarios. This report was produced by the GAP team members and presents an overview of the activities within the GAP during the interval January 1 to December 31, 2010, as well as research results obtained during this time frame. Research for the GAP is ongoing, and additional results related to the data presented here may become available in the future and will be presented in subsequent annual reports. (orig.)

  9. The Greenland analogue project. Yearly report 2010

    International Nuclear Information System (INIS)

    Harper, J.; Brinkerhoff, D.; Johnson, J.; Ruskeeniemi, T.; Engstroem, J.; Kukkonen, I.

    2012-04-01

    A four-year field and modelling study of the Greenland ice sheet and subsurface conditions, Greenland Analogue Project (GAP), has been initiated collaboratively by SKB, Posiva and NWMO to advance the understanding of processes associated with glaciation and their impact on the long-term performance of a deep geological repository. The study site encompasses a land terminus portion of the Greenland ice sheet, east of Kangerlussuaq, and is in many ways considered to be an appropriate analogue of the conditions that are expected to prevail in much of Canada and Fennoscandia during future glacial cycles. The project begins in 2009 and is scheduled for completion in 2012. Our current understanding of the hydrological, hydrogeological and hydrogeochemical processes associated with cold climate conditions and glacial cycles, and their impact on the long-term performance of deep geological repositories for spent nuclear fuel, will be significantly improved by studying a modern analogue. The GAP will conduct the first in situ investigations of some of the parameters and processes needed to achieve a better understanding of how an ice sheet may impact a deep repository, and will provide measurements, observations and data that may significantly improve our safety assessments and risk analyses of glaciation scenarios. This report was produced by the GAP team members and presents an overview of the activities within the GAP during the interval January 1 to December 31, 2010, as well as research results obtained during this time frame. Research for the GAP is ongoing, and additional results related to the data presented here may become available in the future and will be presented in subsequent annual reports. (orig.)

  10. A preliminary feasibility study on natural analogue in Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Chun Soo; Bae, Dae Seok; Kim, Kyung Su; Koh, Yong Kwon; Park, Byung Yun

    2000-03-01

    Preliminary study on the assessment of natural analogue study in Korea for the deep geological disposal of high-level radioactive waste was carried out. The project on natural analogue study in other countries are introduced. The uranium-bearing deposit in Okcheon belt are summarized, which reported to be uranium-bearing minerals in order to assess to feasibility for natural analogue study in Korea. Among the uranium-bearing deposits, the Deokpyeong area, reported to be the highest reservoir and grade, are selected as the study site, and the elementary investigation, including survey of radioactivity and geochemistry are carried out. According to the investigation of surface environment, the radioactivity and uranium content in the surface water and shallow groundwater does not show any anormal values. However, the radioactivity is expected to be increased in depth and the groundwater reacted with uranium-bearing graphite formation shows high unanium content, indicating the potential possibility for natural analogue study in Korea. In future, if more detail study are performed, the assessment of natural analogue study in Korea are expected.

  11. Diferencias en la recaudación del impuesto predial en la zona fronteriza: evidencia en los municipios de Chihuahua

    Directory of Open Access Journals (Sweden)

    Jorge Ibarra Salazar

    2014-01-01

    Full Text Available Basándonos en el estudio de Ibarra y Sotres (2009, en este artículo aportamos evidencia adicional que relaciona las características de la región frontera norte y el marco institucional con la recaudación del impuesto predial. Estimamos una serie de especificaciones econométricas usando una base de datos de panel para los 67 municipios de Chihuahua correspondiente a 2002-2006. Nuestra hipótesis central es que la dinámica económica y demográfica en la zona fronteriza de Chihuahua ha originado una mayor demanda de servicios e infraestructura en los municipios fronterizos de ese estado, lo que los ha motivado a diferenciar su marco institucional para obtener mayores recursos por concepto de impuesto predial en comparación con los municipios no fronterizos. Esto es posible dado que la reforma constitucional de 1999 al Artículo 115 posibilita a los municipios modificar el marco institucional fiscal para enfrentar sus propias peculiaridades.

  12. Effects of thinnings on growth and yield in natural Pinus arizonica and Pinus durangensis stands in the El Largo-Madera region in Chihuahua State

    Science.gov (United States)

    Oscar Estrada Murrieta; Luis A. Dominguez Pereda; Marcelo Zepeda Bautista

    1995-01-01

    This paper presents the result of the first dasometric analysis made with the data of some permanent thinning plots established at different times since 1964 in the Unit of Conservation and Forest Development #2 in Chihuahua State, Mexico. The results show the benefits of thinnings on the growth rates of residual stands, the increment's redistribution, and the...

  13. Superconductive analogue of spin glasses

    International Nuclear Information System (INIS)

    Feigel'man, M.; Ioffe, L.; Vinokur, V.; Larkin, A.

    1987-07-01

    The properties of granular superconductors in magnetic fields, namely the existence of a new superconductive state analogue of the low-temperature superconductive state in spin glasses are discussed in the frame of the infinite-range model and the finite-range models. Experiments for elucidation of spin-glass superconductive state in real systems are suggested. 30 refs

  14. Causal structure of analogue spacetimes

    International Nuclear Information System (INIS)

    Barcelo, Carlos; Liberati, Stefano; Sonego, Sebastiano; Visser, Matt

    2004-01-01

    The so-called 'analogue models of general relativity' provide a number of specific physical systems, well outside the traditional realm of general relativity, that nevertheless are well-described by the differential geometry of curved spacetime. Specifically, the propagation of perturbations in these condensed matter systems is described by 'effective metrics' that carry with them notions of 'causal structure' as determined by an exchange of quasi-particles. These quasi-particle-induced causal structures serve as specific examples of what can be done in the presence of a Lorentzian metric without having recourse to the Einstein equations of general relativity. (After all, the underlying analogue model is governed by its own specific physics, not necessarily by the Einstein equations.) In this paper we take a careful look at what can be said about the causal structure of analogue spacetimes, focusing on those containing quasi-particle horizons, both with a view to seeing what is different from standard general relativity, and what the similarities might be. For definiteness, and because the physics is particularly simple to understand, we will phrase much of the discussion in terms of acoustic disturbances in moving fluids, where the underlying physics is ordinary fluid mechanics, governed by the equations of traditional hydrodynamics, and the relevant quasi-particles are the phonons. It must however be emphasized that this choice of example is only for the sake of pedagogical simplicity and that our considerations apply generically to wide classes of analogue spacetimes

  15. Design and synthesis of 1-(3-(dimethylamino)propyl)-1-(4-fluorophenyl)-1,3-dihydroisobenzofuran-5-carbonitrile (citalopram) analogues as novel probes for the serotonin transporter S1 and S2 binding sites

    DEFF Research Database (Denmark)

    Banala, Ashwini K; Zhang, Peng; Plenge, Per

    2013-01-01

    The serotonin transporter (SERT) is the primary target for antidepressant drugs. The existence of a high affinity primary orthosteric binding site (S1) and a low affinity secondary site (S2) has been described, and their relation to antidepressant pharmacology has been debated. Herein, structural...

  16. Nucleic Acid Analogue Induced Transcription of Double Stranded DNA

    DEFF Research Database (Denmark)

    1998-01-01

    RNA is transcribed from a double stranded DNA template by forming a complex by hybridizing to the template at a desired transcription initiation site one or more oligonucleic acid analogues of the PNA type capable of forming a transcription initiation site with the DNA and exposing the complex...... to the action of a DNA dependant RNA polymerase in the presence of nucleoside triphosphates. Equal length transcripts may be obtained by placing a block to transcription downstream from the initiation site or by cutting the template at such a selected location. The initiation site is formed by displacement...... of one strand of the DNA locally by the PNA hybridization....

  17. Microenvironmental air and soil monitoring of contaminants: An evaluation of indoor and outdoor levels in Chihuahua City

    Science.gov (United States)

    Delgado-Rios, Marcos

    Like most of the cities around the world Chihuahua City suffers atmospheric and soil pollution. This is a problem that requires immediate attention from both public authorities and the scientific community. Although it is known that high levels of heavy metals are present in the airborne particulate matter, soil and dust in many urban regions, the information about personal exposure to these pollutants in Chihuahua City is nonexistent. This study focuses on the analysis and characterization of lead and arsenic in the airborne and soil particulate matter present in the interiors of households and their surrounding outdoor environments in the southern part of Chihuahua City. The sampling area chosen for this study was located in the southern part of Chihuahua City. An atmospheric sampling point selected by the Centro de Investigacion en Materiales Avanzados (CIMAV) was selected as a geographical center, with a 2 km radius forming the sampling area. The households selected for analyses were located on Lombardo Toledano Street, a high-traffic street. The main objectives of this study were to establish the maximum exposure level in outdoor and indoor environments for particulate matter less than 10 mum (PM 10), Pb, and As, to determine the background level of Chihuahua City for these same elements, to determine the isotopic ratios of Pb206 and Pb207 in the indoor and outdoor atmospheric samples, and to verify if the source of the pollution is from anthropogenic and/or natural sources. Additionally, a comparison of the analytical data from X-ray fluorescence (XRF) versus the analytical data from inductively coupled plasma with optical emission spectroscopy (ICP-OES) was conducted. The comparison of these techniques was based on sample preparation, speed of analysis, and accuracy of results. In the case of sample preparation, two extraction techniques were performed for a comparison of the extraction/leaching of Pb and As from the samples. These microwave

  18. Determination of Rn{sup 222} in samples of well water and domicile of the cities of Chihuahua and Aldama, Mexico; Determinacion de Rn{sup 222} en muestras de agua de pozos y domicilio de las ciudades de Chihuahua y Aldama, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Villalba, L.; Colmenero S, L.; Montero C, M.E. [Centro de Investigacion en Materiales Avanzados (CIMAV), Av. Miguel de Cervantes Saavedra 120, 31109 Chihuahua (Mexico)]. e-mail: lourdes.villalba@cimav. edu. mx

    2004-07-01

    The study of the content of dissolved Rn{sup 222} is presented in underground water and of domicile of the cities of Chihuahua and Aldama of the State of Chihuahua. The existence of the Rn{sup 222} in the underground waters comes from its constant production in the rocks of the terrestrial bark. It has been determined that the radon is a noble gas of more solubility in the water, this solubility induces high concentrations in underground water, as well as bigger risk to the health in the human body once ingested or inhaled. Of the 32 wells studied in the cities of Chihuahua and Aldama, the content of dissolved Rn{sup 222} in the water of 22 of them is bigger than 11 Bq/l and of 73 studied samples of water of domiciles 47 show bigger values that 11 Bq/l. These radon contents are attributable to the uraniferous rocks present in the aquifers. (Author)

  19. Natural analogues, paradigm for manmade repositories for radioactive wastes

    International Nuclear Information System (INIS)

    Pavelescu, M.; Pavelescu, A.

    2004-01-01

    Natural analogues are given by nature. They show the results of natural processes which have lasted thousands or millions of years. They provide an excellent example of what could happen in an underground site, offering in the same time the opportunity to test by observation and measurement, many of the geochemical processes that are expected to influence in a realistic and appropriate way, the predicted reliability of the radioactive waste repository over long periods of geological time. The natural analogue studies attempt to understand the multiprocessing complexity of the natural system, which contrasts with the limitations of the laboratory experiments and bring arguments to overcome the difficult time scale issue. By this the natural analogues are a useful paradigm for manmade repository for radioactive wastes. The paper discusses the implicit link in the public mind between natural analogues and manmade waste repository with an accent of the positive impact on public acceptance. It is also discussed the decisive qualities of the natural analogues concerning providing valid long term data and increasing the confidence of the public for manmade repositories. The debate is conducting in terms of sustainable development, having at base high-level principles in order to protect humans and their environment, both now and in the future, from potential hazards arising from such wastes. Safe radwaste management involves the application of technology and resources in a regulated manner so that the public, workers and the environment are protected in accordance with the accepted national and international standards. There are at least seven high-level principles which are mentioned in the paper. It is presented the general concept of the deep geological repository, very important for an acceptable solution for the management of nuclear waste, what is a prerequisite for a renewal of nuclear power. Further are introduced natural and archaeological (manufactured) analogue

  20. Aspects of radiological safety and protection in the decontamination of the Benefit plant of uranium in Ciudad Aldama and in the storage of its residues in Pena Blanca, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Ruiz C, M.A.

    1998-01-01

    Between 1969 and 1971 the National Commission of Nuclear Energy and the Mining Fostering Commission operated coordinately a production plant of uranium and molybdenum concentrates (Benefit plant) at Ciudad Aldama, Chihuahua, Mexico. During two years of operation some 45 tonnes of uranium concentrate and approximately 35,000 tonnes of uranium wetlands were produced. These last were stored in a dam to 120 m. toward West of the plant. Due to the nearness of the population with respect to what was the Benefit plant and over all to the wetland dam, the objective of this work had two main aspects: On the one hand, to carry out the works of radiological decontamination of the benefit plant of uranium, according to the established normative by the Regulatory organization in matter of radiological safety and protection (CNSNS) for the population and the hard workers. After that the works mentioned were realized it was considered that the estate which comprises what was the Benefit plant did not reach the established criteria by the CNSNS for being considered of unrestricted use such estate and it was not allowed any type of construction in the zone which could be showed the residual contamination which remains there. On the other hand, to determine the site where could be stored the radioactive wastes generated by the radiological decontamination and the wetland mobilization for its definitive storage in benefit of the present population and of the future generations due to the radionuclides which are in a such material. The site more adequate technical and economically to storage the wastes generated by this activity was evaluated. Whereby studies about demography, use of soil and water, meteorology, hydrology and ecology were realized. The site selected being in the Pena Blanca mountains, Chihuahua, place where is located one of the uranium zones and the most important of the country. In this work, specific objectives also were treated such as: knowing the radiological

  1. MAQARIN natural analogue study: phase III

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, W R; Mazurek, M; Waber, H N [Univ. of Berne (Switzerland). Institutes of Geology, Mineralogy and Petrology, Rock-Water Interaction Group (GGWW); Arlinger, J; Erlandson, A C; Hallbeck, L; Pedersen, K [Goeteborg University (Sweden). Dept. of General and Marine Microbiology; Boehlmann, W; Fritz, P; Geyer, S; Geyer, W; Hanschman, G; Kopinke, F D; Poerschmann, J [Umweltforschungszentrum Leipzig-Halle (Germany); Chambers, A V; Haworth, A; Ilett, D; Linklater, C M; Tweed, C J [AEA Technology plc, Harwell (United Kingdom); Chenery, S R.N.; Kemp, S J; Milodowski, A E; Pearce, J M; Reeder, S; Rochelle, C A; Smith, B; Wetton, P D; Wragg, J [British Geological Survey, Keyworth (United Kingdom); Clark, I D [Univ. of Ottawa (Canada). Dept. of Geology; Hodginson, E; Hughes, C R [Univ. of Manchester (United Kingdom). Dept. of Earth Sciences; Hyslop, E K [British Geological Survey, Edinburgh (United Kingdom); Karlsson, F [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Khoury, H N; Salameh, E [Univ. of Jordan, Amman (Jordan); Lagerblad, B [Cement Institute, Stockholm (Sweden); Longworth, G [Univ. of Manchester (United Kingdom). Dept. of Geology; Pitty, A F [Private consultant, Norwich (United Kingdom); Savage, D [QuantiSci Ltd, Melton Mowbray (United Kingdom); Smellie, J A.T. [ed.; Conterra AB, Uppsala (Sweden)

    1998-12-01

    This report represents the conclusion to Phase III of the Maqarin Natural Analogue Study. The main thrust was to establish the origin and chemistry of the Western Springs hyper alkaline groundwaters (Na/K enriched Ca(OH){sub 2} type) and to study their interaction with rocks of different compositions, as natural analogues to key processes that might occur at an early stage within the `alkali disturbed zone` of cementitious repositories in different host rocks. Whilst earlier studies at Maqarin were very much site-specific and process-oriented, Phase III provided a regional perspective to the geological evolution of the Maqarin region. This was made possible by greater field access which allowed a more systematic structural and geomorphological study of the area. This has resulted in a greater understanding of the age and spatial relationships concerning formation of the cement zones through spontaneous combustion of the Bituminous Marls, and the subsequent formation of high pH groundwaters at the Eastern and Western Springs locations. At the Western Springs locality, hydrochemical and hydrogeological evaluation of new and published data (plus access to unpublished data), together with detailed mineralogical and geochemical studies, helped to clarify the very earliest stage of cement leachate/host rock interaction. The data were used also to test coupled flow/transport codes developed to assess the long-term evolution of a cementitious repository. Additional objectives addressed include: a) rock matrix diffusion, b) the occurrence and chemical controls on zeolite composition, e) the occurrence and chemical controls on clay stability, and d) the role of microbes, organics and colloids in trace element transport. The Maqarin site now provides a consistent picture explaining the origin of the hyperalkaline groundwaters, and is therefore a unique location for the examination of the mechanisms and processes associated with cementitious repositories. Application of these

  2. MAQARIN natural analogue study: phase III

    International Nuclear Information System (INIS)

    Alexander, W.R.; Mazurek, M.; Waber, H.N.; Arlinger, J.; Erlandson, A.C.; Hallbeck, L.; Pedersen, K.; Chambers, A.V.; Haworth, A.; Ilett, D.; Linklater, C.M.; Tweed, C.J.; Chenery, S.R.N.; Kemp, S.J.; Milodowski, A.E.; Pearce, J.M.; Reeder, S.; Rochelle, C.A.; Smith, B.; Wetton, P.D.; Wragg, J.; Clark, I.D.; Karlsson, F.; Khoury, H.N.; Salameh, E.; Lagerblad, B.; Longworth, G.; Savage, D.; Smellie, J.A.T.

    1998-12-01

    This report represents the conclusion to Phase III of the Maqarin Natural Analogue Study. The main thrust was to establish the origin and chemistry of the Western Springs hyper alkaline groundwaters (Na/K enriched Ca(OH) 2 type) and to study their interaction with rocks of different compositions, as natural analogues to key processes that might occur at an early stage within the 'alkali disturbed zone' of cementitious repositories in different host rocks. Whilst earlier studies at Maqarin were very much site-specific and process-oriented, Phase III provided a regional perspective to the geological evolution of the Maqarin region. This was made possible by greater field access which allowed a more systematic structural and geomorphological study of the area. This has resulted in a greater understanding of the age and spatial relationships concerning formation of the cement zones through spontaneous combustion of the Bituminous Marls, and the subsequent formation of high pH groundwaters at the Eastern and Western Springs locations. At the Western Springs locality, hydrochemical and hydrogeological evaluation of new and published data (plus access to unpublished data), together with detailed mineralogical and geochemical studies, helped to clarify the very earliest stage of cement leachate/host rock interaction. The data were used also to test coupled flow/transport codes developed to assess the long-term evolution of a cementitious repository. Additional objectives addressed include: a) rock matrix diffusion, b) the occurrence and chemical controls on zeolite composition, e) the occurrence and chemical controls on clay stability, and d) the role of microbes, organics and colloids in trace element transport. The Maqarin site now provides a consistent picture explaining the origin of the hyperalkaline groundwaters, and is therefore a unique location for the examination of the mechanisms and processes associated with cementitious repositories. Application of these

  3. Natural analogues in Posiva's Safety Case

    International Nuclear Information System (INIS)

    Marcos, Nuria; Seppaelae, T.

    2008-01-01

    The Safety Case is a broader concept than Performance Assessment that allows better the use of natural analogues and observations from nature to understand the behaviour of the system and the processes at the site. Natural analogues are mostly use to add confidence to the safety of geological disposal with respect to: Design (depth and multi-barrier system), Materials (long-term durability), and Processes (understanding the long-term behaviour/evolution of the system). Ice ages and erosion: largest boulders released and transported by ice during the most recent ice age are well below 20 m. 25 glacial cycles would be necessary to erode in this fashion 500 m of bedrock. During the last million years only about 8-9 glacial cycles are known to have occurred. Geosphere stability: Minor possibility of damaging earthquakes due to the geological position of the Olkiluoto site in the Fennoscandian Shield. Magnitudes of earthquakes historically and over the last 40 years have been less than 3 in the area next to Olkiluoto. Stability, U, and flow rates at Olkiluoto: Shallow ground-waters: Assuming a discharge flow rate (DFR) of about 200000 m"3/km"2/year, the average concentration of U in gw was 3.7 μg/L. At depth 375 m: Assuming a discharge flow rate of about 1680 m"3/km"2/year, the average concentration of U in gw was 0.21 μg/L. At depth 475 m: Discharge flow rate of about 730 m"3/km"2/year, the average concentration of U in gw was 0.04 μg/L

  4. MAQARIN natural analogue study: phase III

    Energy Technology Data Exchange (ETDEWEB)

    Alexander, W R; Mazurek, M; Waber, H N [Univ. of Berne (Switzerland). Institutes of Geology, Mineralogy and Petrology, Rock-Water Interaction Group (GGWW); Arlinger, J; Erlandson, A C; Hallbeck, L; Pedersen, K [Goeteborg Univ. (Sweden). Dept. of General and Marine Microbiology; Boehlmann, W; Fritz, P; Geyer, S; Geyer, W; Hanschman, G; Kopinke, F D; Poerschmann, J [Umweltforschungszentrum Leipzig-Halle (Germany); Chambers, A V; Haworth, A; Ilett, D; Linklater, C M; Tweed, C J [AEA Technology plc, Harwell (United Kingdom); Chenery, S R.N.; Kemp, S J; Milodowski, A E; Pearce, J M; Reeder, S; Rochelle, C A; Smith, B; Wetton, P D; Wragg, J [British Geological Survey, Keyworth (United Kingdom); Clark, I D [Univ. of Ottawa (Canada). Dept. of Geology; Hodginson, E; Hughes, C R [Univ. of Manchester (United Kingdom). Dept. of Earth Sciences; Hyslop, E K [British Geological Survey, Edinburgh (United Kingdom); Karlsson, F [Swedish Nuclear Fuel and Waste Management Co., Stockholm (Sweden); Khoury, H N; Salameh, E [Univ. of Jordan, Amman (Jordan); Lagerblad, B [Cement Inst., Stockholm (Sweden); Longworth, G [Univ. of Manchester (United Kingdom). Dept. of Geology; Pitty, A F [Private consultant, Norwich (United Kingdom); Savage, D [QuantiSci Ltd, Melton Mowbray (United Kingdom); Smellie, J A.T. [ed.; Conterra AB, Uppsala (Sweden)

    1998-12-01

    This report represents the conclusion to Phase III of the Maqarin Natural Analogue Study. The main thrust was to establish the origin and chemistry of the Western Springs hyper alkaline groundwaters (Na/K enriched Ca(OH){sub 2} type) and to study their interaction with rocks of different compositions, as natural analogues to key processes that might occur at an early stage within the `alkali disturbed zone` of cementitious repositories in different host rocks. Whilst earlier studies at Maqarin were very much site-specific and process-oriented, Phase III provided a regional perspective to the geological evolution of the Maqarin region. This was made possible by greater field access which allowed a more systematic structural and geomorphological study of the area. This has resulted in a greater understanding of the age and spatial relationships concerning formation of the cement zones through spontaneous combustion of the Bituminous Marls, and the subsequent formation of high pH groundwaters at the Eastern and Western Springs locations. At the Western Springs locality, hydrochemical and hydrogeological evaluation of new and published data (plus access to unpublished data), together with detailed mineralogical and geochemical studies, helped to clarify the very earliest stage of cement leachate/host rock interaction. The data were used also to test coupled flow/transport codes developed to assess the long-term evolution of a cementitious repository. Additional objectives addressed include: a) rock matrix diffusion, b) the occurrence and chemical controls on zeolite composition, e) the occurrence and chemical controls on clay stability, and d) the role of microbes, organics and colloids in trace element transport. The Maqarin site now provides a consistent picture explaining the origin of the hyperalkaline groundwaters, and is therefore a unique location for the examination of the mechanisms and processes associated with cementitious repositories. Application of these

  5. Status of natural analogue studies

    International Nuclear Information System (INIS)

    Sekine, Keiichi

    1994-03-01

    This report is based on the materials for the meeting at the Nuclear Safety Commission of Japan held on September 1993. Details are as follows: Alteration of glass as the study of alteration of natural minerals; alteration of uranium minerals, migration of uranium and thorium series radionuclides, alteration of chlorite, fixation of uranium alteration of minerals and migration of uranium as the study of alligator rivers analogue project held at Koongarra uranium deposit, Australia. (author)

  6. Ribosome-catalyzed formation of an abnormal peptide analogue

    International Nuclear Information System (INIS)

    Roesser, J.R.; Chorghade, M.S.; Hecht, S.M.

    1986-01-01

    The peptidyl-tRNA analogue N-(chloracetyl) phenylalanyl-tRNA/sup Phe/ was prepared by chemical aminoacylation and prebound to the P site of Escherichia coli ribosomes in response to poly(uridylic acid). Admixture of phenylalanyl-tRNA/sup Phe/ to the A site resulted in the formation of two dipeptides, one of which was found by displacement of chloride ion from the peptidyl-tRNA. This constitutes the first example of ribosome-mediated formation of a peptide of altered connectivity and suggests a need for revision of the current model of peptide bond formation. Also suggested by the present finding is the feasibility of utilizing tRNAs to prepare polypeptides of altered connectivity in an in vitro protein biosynthesizing system. [ 32 P]-oligo(rA), [ 3 H]- and [ 14 C] phenylalanines were used in the assay of the peptidye-tRNA analogue

  7. EL PROCESO DE TRABAJO PARTICIPATIVO EN LA EVALUACIÓN DE BIBLIOTECAS UNIVERSITARIAS: CASO UNIVERSIDAD AUTÓNOMA DE CHIHUAHUA

    Directory of Open Access Journals (Sweden)

    Javier Tarango Ortiz

    2009-01-01

    Full Text Available Se describe la experiencia obtenida en el sistema de bibliotecas de la Universidad Autónoma de Chihuahua durante el diseño y validación de un plan de evaluación a partir del empleo de un modelo de trabajo participativo. El modelo propuesto es sustentado en una revisión de la literatura de los trabajos relacionados al tema de la evaluación de las bibliotecas universitarias en México, así como los principios generales de la metaevaluación y evaluación. El trabajo concluye analizando las condiciones que propician desarrollar evaluaciones bibliotecarias a través de la participación e identifica los retos que debe enfrentar el profesional de la in-formación al desarrollar procesos evaluatorios no convencionales.

  8. Spatial Analysis of the National Evaluation of Scholastic Achievement (ENLACE in Schools of the Municipality of Juarez, Chihuahua

    Directory of Open Access Journals (Sweden)

    Luis Ernesto Cervera Gómez

    2008-05-01

    Full Text Available This research was focused on analyzing the results of the first National Assessment of Academic Achievement for Scholar Centers (ENLACE; acronym in Spanish applied during the year 2006 in the Municipality of Juarez (State of Chihuahua, Mexico. In order to conduct the spatial analysis a geographical information system (GIS was used to make a georeferenced database were all variables were connected to a point representing a school. Results of the examinations expressed as deficient, elemental, good en excellent were spatially distributed over the urban area of Ciudad Juárez. Apparently there is a high spatial correlation between ENLACE’s results with the socioeconomic level of people. In this way results going from good to excellent were spatially located over the sectors more developed of the city. Poor results going from Insufficient to Elemental were spatially located at places with higher deficits of infrastructure and low socioeconomic levels.

  9. First-year performance of the Chorreras pv-hybrid ice-making system in Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Estrada, Luis; Foster, Robert; Cota, Alma D [Southwest Technology Development Institute, Las Cruces, New Mexico (United States)

    2000-07-01

    This paper describes the reliability and performance of the Chorreras photovoltaic (PV) hybrid ice-making system. The system is a first of its kind in the world and is located near the fishing village of Chorreras, which is located along a man-made lake in a remote desert area of the State of Chihuahua in northern Mexico. The information gathered from technical field visits and a GOES satellite-based data collection system are reviewed to discuss system design and operation. The system has been working well in producing ice on a daily basis with only some minor control problems and water line calcification that reduced ice production until the line was cleaned. The hybrid system provides a daily average of 8.9 kWh at 240 volts to the ice-maker. The system Coefficient of Performance (COP) is about 0.65 and a total of 97 percent of the energy has been supplied by the PV array, while only 3 percent has been supplied by the back-up propane-fueled generator. Production of ice varies slightly each month due to changes in insolation and ambient temperatures. Overall ice production averages about 85 kg of ice per day. This project and this paper are dedicated to the memory of Ing. Juan Jose Onate Rodriguez from the Direccion General de Desarrollo Rural, who was the original project developer for the State of Chihuahua. [Spanish] Este articulo describe la confiabilidad y el rendimiento del sistema hibrido fotovoltaico (PV) de Chorreras para produccion de hielo. El sistema es el primero en su tipo en el mundo y esta localizado cerca del pueblo de pescadores de Chorreras, a la orilla de un lago artificial en un area desertica remota en el estado de Chihuahua, al norte de Mexico. Se esta revisando la informacion recopilada por las visitas tecnicas de campo y por el sistema de recoleccion de datos satelital GOES para analizar el diseno y operacion del sistema, que ha estado funcionando con buenos resultados en la produccion diaria de hielo, teniendo solo problemas menores de

  10. Uranium-series isotopes transport in surface, vadose and ground waters at San Marcos uranium bearing basin, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Burillo Montúfar, Juan Carlos; Reyes Cortés, Manuel; Reyes Cortés, Ignacio Alfonso; Espino Valdez, Ma. Socorro; Hinojosa de la Garza, Octavio Raúl; Nevárez Ronquillo, Diana Pamela; Herrera Peraza, Eduardo; Rentería Villalobos, Marusia; Montero Cabrera, María Elena

    2012-01-01

    In the U deposit area at San Marcos in Chihuahua, Mexico, hydrogeological and climatic conditions are very similar to the Nopal I, Peña Blanca U deposit, 50 km away. The physicochemical parameters and activity concentrations of several 238 U-series isotopes have been determined in surface, vadose and ground waters at San Marcos. The application of some published models to activity ratios of these isotopes has allowed assessing the order of magnitude of transport parameters in the area. Resulting retardation factors in San Marcos area are R f238 ≈ 250–14,000 for the unsaturated zone and ≈110–1100 for the saturated zone. The results confirm that the mobility of U in San Marcos is also similar to that of the Nopal I U deposit and this area can be considered as a natural analog of areas suitable for geologic repositories of high-level nuclear waste.

  11. Lung Cancer Mortality and Radon Concentration in a Chronically Exposed Neighborhood in Chihuahua, Mexico: A Geospatial Analysis

    Science.gov (United States)

    Hinojosa de la Garza, Octavio R.; Sanín, Luz H.; Montero Cabrera, María Elena; Serrano Ramirez, Korina Ivette; Martínez Meyer, Enrique; Reyes Cortés, Manuel

    2014-01-01

    This study correlated lung cancer (LC) mortality with statistical data obtained from government public databases. In order to asses a relationship between LC deaths and radon accumulation in dwellings, indoor radon concentrations were measured with passive detectors randomly distributed in Chihuahua City. Kriging (K) and Inverse-Distance Weighting (IDW) spatial interpolations were carried out. Deaths were georeferenced and Moran's I correlation coefficients were calculated. The mean values (over n = 171) of the interpolation of radon concentrations of deceased's dwellings were 247.8 and 217.1 Bq/m3, for K and IDW, respectively. Through the Moran's I values obtained, correspondingly equal to 0.56 and 0.61, it was evident that LC mortality was directly associated with locations with high levels of radon, considering a stable population for more than 25 years, suggesting spatial clustering of LC deaths due to indoor radon concentrations. PMID:25165752

  12. Participación ciudadana en las colonias sin agua potable y alcantarillado de Ciudad Juárez, Chihuahua

    Directory of Open Access Journals (Sweden)

    Gustavo Córdova Bojórquez

    2007-01-01

    Full Text Available En este artículo se presenta un análisis de la participación ciudadana en la gestión del agua en 14 colonias que carecen del servicio de agua potable y alcantarillado en Ciudad Juárez, Chihuahua. La metodología consistió en analizar y relacionar las influencias externas e internas de los ciudadanos resultando una participación ciudadana muy baja en la gestión del agua determinada en gran medida por el poco conocimiento sobre el tema, la poca confianza en las instituciones públicas, la mínima disposición de participar en proyectos comunitarios y por la gran influencia que tiene el sistema político en la gestión del servicio.

  13. The involvement of citizens and water management: Neighborhood committees leaders in Ciudad Juárez, Chihuahua

    Directory of Open Access Journals (Sweden)

    Gustavo Córdova Bojórquez

    2005-07-01

    Full Text Available This paper seeks to analyze public participation in water management through a survey applied to the leaders of neighborhood committees in Ciudad Juarez, Chihuahua. As part of the methodology, two variables —external and internal influences— and fourteen indicators were utilized. Results show that neighborhood committees, as a public participation structure, are in crisis. The structure shows both internal and external signs of breaking up: there are no clear mechanisms of summons or participation, nor are there any adecuate mechanisms capable of articulating demands and government authority, insofar as external political agents have been allowed to participate in internal management and committee issues. For this reason, the capacity of local neighborhood committees to make decisions regarding city water management is placed in doubt.

  14. U-series in Fe(III)-U(VI) rich fracture infill-materials from the oxidised cap of the U-ore deposit of Mina Fe (Salamanca, Spain): Implications for water/rock interaction processes affecting and analogue site (Matrix II project)

    International Nuclear Information System (INIS)

    Perez del Villar, L.; Grespo, M. T.; Quejido, A. J.

    2002-01-01

    In the frame of the ENRESA natural analogue programme. The U-ore deposit of Mina Fe being studied as a natural analogue of radioactive spent fuel behaviour. In this context the knowledge of the role played by fracture minerals as scavengers of certain analogue elements. Mainly U, and the establishment of the time scale of the rock-water interaction processes controlling the uptakes or losses of U in the system are two relevant objectives

  15. Evaluación de la propuesta de intervención para estudiantes sobresalientes: caso Chihuahua, México

    Directory of Open Access Journals (Sweden)

    Covarrubias Pizarro, Pedro

    2015-09-01

    Full Text Available Este artículo tiene como propósito exponer los resultados de un trabajo de investigación evaluativa realizado para valorar la implementación de la Propuesta de Intervención Educativa para alumnos y alumnas con Aptitudes Sobresalientes, puesta en marcha por la Secretaría de Educación Pública de México durante el ciclo escolar 2007-2008. Para evaluar dicha propuesta, se diseñó y aplicó un modelo conformado por cuatro componentes, cuatro criterios y trece descriptores. Para la recuperación de los datos y su análisis correspondiente, se empleó una metodología de corte mixto que consideró diferentes momentos, actores e instrumentos. En este documento se presenta el trabajo realizado mediante el enfoque cualitativo, destacando los resultados obtenidos en los grupos de discusión y las entrevistas semiestructuradas. El estudio se llevó a cabo en el estado de Chihuahua, México y participaron como informantes significativos el personal de educación especial del subsistema estatal del estado de Chihuahua, padres y madres de familia de estudiantes sobresalientes, maestras de grupo regular, alumnado identificado como sobresaliente y personas expertas en el tema de las altas capacidades. Los resultados apuntan que la propuesta de intervención valorada cuenta con cualidades relacionadas con su fundamento teórico y metodológico, sin embargo, la mayor debilidad se ubica en la operatividad, aspecto que puede ser sujeto a mejorar para la obtención de mayores resultados en la intervención.

  16. EVALUACIÓN DE LA PROPUESTA DE INTERVENCIÓN PARA ESTUDIANTES SOBRESALIENTES: CASO CHIHUAHUA, MÉXICO

    Directory of Open Access Journals (Sweden)

    Pedro Covarrubias Pizarro

    2015-01-01

    Full Text Available Este artículo tiene como propósito exponer los resultados de un trabajo de investigación evaluativa realizado para valorar la implementación de la Propuesta de Intervención Educativa para alumnos y alumnas con Aptitudes Sobresalientes, puesta en marcha por la Secretaría de Educación Pública de México durante el ciclo escolar 2007-2008. Para evaluar dicha propuesta, se diseñó y aplicó un modelo conformado por cuatro componentes, cuatro criterios y trece descriptores. Para la recuperación de los datos y su análisis correspondiente, se empleó una metodología de corte mixto que consideró diferentes momentos, actores e instrumentos. En este documento se presenta el trabajo realizado mediante el enfoque cualitativo, destacando los resultados obtenidos en los grupos de discusión y las entrevistas semiestructuradas. El estudio se llevó a cabo en el estado de Chihuahua, México y participaron como informantes significativos el personal de educación especial del subsistema estatal del estado de Chihuahua, padres y madres de familia de estudiantes sobresalientes, maestras de grupo regular, alumnado identificado como sobresaliente y personas expertas en el tema de las altas capacidades. Los resultados apuntan que la propuesta de intervención valorada cuenta con cualidades relacionadas con su fundamento teórico y metodológico, sin embargo, la mayor debilidad se ubica en la operatividad, aspecto que puede ser sujeto a mejorar para la obtención de mayores resultados en la intervención.

  17. La organización de las escuelas secundarias del estado de Chihuahua, en el marco de la reforma educativa

    Directory of Open Access Journals (Sweden)

    David Manuel Arzola Franco

    2010-10-01

    Full Text Available El presente artículo se deriva de un proyecto de investigación apoyado por el Fondo Mixto CONACYT-Gobierno del Estado de Chihuahua, cuyo propósito consiste en indagar sobre la visión que tienen los actores involucrados en la Reforma de la Educación Secundaria (RS, con respecto a los procesos de transformación que se pretenden operar en el ámbito organizativo. El trabajo se llevó a cabo a través de la aplicación de una encuesta, a una muestra representativa de docentes, directivos, alumnos y padres/madres de familia, de escuelas secundarias, generales y técnicas, del estado de Chihuahua. El análisis está centrado en algunos aspectos relacionados con la organización de los 43 centros educativos: el funcionamiento institucional, los procesos comunicativos, las acciones de orientación y tutoría, el trabajo colaborativo; la información sobre la dinámica para la implementación de la Reforma de la Educación Secundaria (RS, y las perspectivas de los sujetos con respecto al manejo de los indicadores educativos a nivel institucional. Los datos recabados ponen de relieve que la RS se limita al cambio del plan y los programas de estudio; no se advierten transformaciones en la estructura organizativa de las escuelas de este nivel: formas de gobierno, aspectos normativos, procesos de comunicación y participación, toma de decisiones, etc.

  18. Mujeres indígenas, gobierno y comunidad: El caso de mujeres tarahumaras en Ciudad Juárez, Chihuahua

    Directory of Open Access Journals (Sweden)

    Martha Estela Pérez García

    2016-01-01

    Full Text Available La situación de las mujeres indígenas en Chihuahua se caracteriza por la marginación, pobreza y desigualdad. Por esta razón, algunos(as miembros de la etnia rarámuri obligados por las necesidades más elementales, emigran con sus familias a las principales ciudades de la entidad. En el caso específico de la comunidad indígena asentada en Ciudad Juárez, Chihuahua, encontramos que son mujeres quienes dirigen las tareas de gobierno, rol tradicionalmente asignados a los hombres. El objetivo de este artículo es realizar un acercamiento de la participación femenina en el gobierno de la colonia tarahumara, con el propósito de conocer cómo se genera esta participación, sus liderazgos y las formas de resolución de sus problemas al interior de la comunidad. Para este propósito se realizaron entrevista con representantes de la comunidad y sus dos gobernadoras, además de un grupo focal con la presidenta y un grupo de mujeres. Los resultados de esta investigación mostraron dos cuestiones significativas: la situación de extrema vulnerabilidad en que viven las indígenas en el entorno urbano y que el gobierno femenino usa estrategias apegadas al rol de género para mantener el orden, el liderazgo y mejorar la calidad de vida de su comunidad.

  19. Defining reference conditions for acidified waters using a modern analogue approach

    International Nuclear Information System (INIS)

    Simpson, Gavin L.; Shilland, Ewan M.; Winterbottom, Julie M.; Keay, Janey

    2005-01-01

    Analogue matching is a palaeolimnological technique that aims to find matches for fossil sediment samples from a set of modern surface sediment samples. Modern analogues were identified that closely matched the pre-disturbance conditions of eight of the UK Acid Waters Monitoring Network (AWMN) lakes using diatom- and cladoceran-based analogue matching. These analogue sites were assessed in terms of hydrochemistry, aquatic macrophytes and macro-invertebrates as to their suitability for defining wider hydrochemical and biological reference conditions for acidified sites within the AWMN. The analogues identified for individual AWMN sites show a close degree of similarity in terms of their hydrochemical characteristics, aquatic macrophytes and, to a lesser extent, macro-invertebrate fauna. The reference conditions of acidified AWMN sites are inferred to be less acidic than today and to support a wider range of acid-sensitive aquatic macrophyte and macro-invertebrate taxa than that recorded in the AWMN lakes over the period of monitoring since 1988. - The use of a palaeolimnological technique to identify modern ecological reference analogues for acidified lakes is demonstrated

  20. Modeling of U-series Radionuclide Transport Through Soil at Pena Blanca, Chihuahua, Mexico

    Science.gov (United States)

    Pekar, K. E.; Goodell, P. C.; Walton, J. C.; Anthony, E. Y.; Ren, M.

    2007-05-01

    The Nopal I uranium deposit is located at Pena Blanca in Chihuahua, Mexico. Mining of high-grade uranium ore occurred in the early 1980s, with the ore stockpiled nearby. The stockpile was mostly cleared in the 1990s; however, some of the high-grade boulders have remained there, creating localized sources of radioactivity for a period of 25-30 years. This provides a unique opportunity to study radionuclide transport, because the study area did not have any uranium contamination predating the stockpile in the 1980s. One high-grade boulder was selected for study based upon its shape, location, and high activity. The presumed drip-line off of the boulder was marked, samples from the boulder surface were taken, and then the boulder was moved several feet away. Soil samples were taken from directly beneath the boulder, around the drip-line, and down slope. Eight of these samples were collected in a vertical profile directly beneath the boulder. Visible flakes of boulder material were removed from the surficial soil samples, because they would have higher concentrations of U-series radionuclides and cause the activities in the soil samples to be excessively high. The vertical sampling profile used 2-inch thicknesses for each sample. The soil samples were packaged into thin plastic containers to minimize the attenuation and to standardize sample geometry, and then they were analyzed by gamma-ray spectroscopy with a Ge(Li) detector for Th-234, Pa-234, U-234, Th-230, Ra-226, Pb-214, Bi-214, and Pb-210. The raw counts were corrected for self-attenuation and normalized using BL-5, a uranium standard from Beaverlodge, Saskatchewan. BL-5 allowed the counts obtained on the Ge(Li) to be referenced to a known concentration or activity, which was then applied to the soil unknowns for a reliable calculation of their concentrations. Gamma ray spectra of five soil samples from the vertical profile exhibit decreasing activities with increasing depth for the selected radionuclides

  1. Evolving a polymerase for hydrophobic base analogues.

    Science.gov (United States)

    Loakes, David; Gallego, José; Pinheiro, Vitor B; Kool, Eric T; Holliger, Philipp

    2009-10-21

    Hydrophobic base analogues (HBAs) have shown great promise for the expansion of the chemical and coding potential of nucleic acids but are generally poor polymerase substrates. While extensive synthetic efforts have yielded examples of HBAs with favorable substrate properties, their discovery has remained challenging. Here we describe a complementary strategy for improving HBA substrate properties by directed evolution of a dedicated polymerase using compartmentalized self-replication (CSR) with the archetypal HBA 5-nitroindole (d5NI) and its derivative 5-nitroindole-3-carboxamide (d5NIC) as selection substrates. Starting from a repertoire of chimeric polymerases generated by molecular breeding of DNA polymerase genes from the genus Thermus, we isolated a polymerase (5D4) with a generically enhanced ability to utilize HBAs. The selected polymerase. 5D4 was able to form and extend d5NI and d5NIC (d5NI(C)) self-pairs as well as d5NI(C) heteropairs with all four bases with efficiencies approaching, or exceeding, those of the cognate Watson-Crick pairs, despite significant distortions caused by the intercalation of the d5NI(C) heterocycles into the opposing strand base stack, as shown by nuclear magnetic resonance spectroscopy (NMR). Unlike Taq polymerase, 5D4 was also able to extend HBA pairs such as Pyrene: varphi (abasic site), d5NI: varphi, and isocarbostyril (ICS): 7-azaindole (7AI), allowed bypass of a chemically diverse spectrum of HBAs, and enabled PCR amplification with primers comprising multiple d5NI(C)-substitutions, while maintaining high levels of catalytic activity and fidelity. The selected polymerase 5D4 promises to expand the range of nucleobase analogues amenable to replication and should find numerous applications, including the synthesis and replication of nucleic acid polymers with expanded chemical and functional diversity.

  2. Variation effect on the insecticide activity of DDT analogues. A chemometric approach

    Science.gov (United States)

    Itoh, S.; Nagashima, U.

    2002-08-01

    We investigated a variation effect on the insecticide activity of DDT analogues by using the first principles electronic structure calculations and the neural network analysis. It has been found that the charge distribution at the specific atomic sites in the DDT molecule is related to their toxicity. This approach can contribute to designing a new insecticide and a new harmlessness process of the DDT analogues.

  3. Conmemoraciones históricas, activación y posicionamiento turístico: Centenario, Bicentenario y Tricentenario en Chihuahua

    Directory of Open Access Journals (Sweden)

    Anna María Fernández Poncela

    2011-01-01

    Full Text Available Este texto es una revisión y reflexión sobre algunos conceptos y fenómenos sociales con relación al patrimonio cultural, las conmemoraciones históricas y el turismo cultural. El estudio de caso es la triple celebración en Chihuahua, Centenario de la Revolución Mexicana, Bicentenario de la Independencia de México y Tricentenario de la fundación de la ciudad capital del estado de Chihuahua. Con este ejemplo, se observa cómo se reproduce y consume la identidad nacional, el patrimonio histórico y cultural -tangible e intangible- y cómo el turismo consume identidad y patrimonio. Desde el presente exaltamos el pasado y proyectamos expectativas hacia el futuro.

  4. Natural and archaeological analogues: a review

    International Nuclear Information System (INIS)

    Brookins, D.G.

    1987-01-01

    In this chapter natural analogues in the geomedia for various aspects of radioactive waste disposal are discussed. Particular reference is made to the Okla Natural Reactor in Gabon. Igneous contact zones are discussed and natural analogues of waste-form materials. The importance of archaeological remains and anthropogenic materials left by man, in assessing weathering conditions and serving as radioactive waste analogues, is also emphasised. (UK)

  5. Bentonite analogue research related to geological disposal of radioactive waste: current status and future outlook

    Energy Technology Data Exchange (ETDEWEB)

    Reijonen, H.M. [Saanio and Rickkola Oy, Helsinki (Finland); Russel, A.W. [Bedrock Geosciences, Auenstein (Switzerland)

    2015-06-15

    The practice of utilising natural analogues in assessing the long-term behaviour of various components of geological repositories for radioactive waste is already well established in most disposal programmes. Numerous studies on bentonites, focussing on bentonite interaction with other components of the engineered barrier system and a range of host rock environments, are present in the literature. In this article, recent bentonite natural analogue studies are briefly reviewed, and gaps in the current literature identified, with the aim of (1) suggesting where relevant new information could be obtained by data mining published bentonite natural analogue studies with a new focus on current safety case requirements, (2) collecting relevant information by revisiting known bentonite analogue sites and conducting investigations with more appropriate analytical techniques, and (3) identifying novel study sites where, for example, bentonite longevity in very dilute to highly saline groundwater conditions can be studied. It must be noted that the use of natural analogues in safety case development is likely to be site and repository design-specific in nature and thus emphasis is placed on the appropriate use of relevant natural analogue data on bentonite longevity. (authors)

  6. Bentonite analogue research related to geological disposal of radioactive waste: current status and future outlook

    International Nuclear Information System (INIS)

    Reijonen, H.M.; Russel, A.W.

    2015-01-01

    The practice of utilising natural analogues in assessing the long-term behaviour of various components of geological repositories for radioactive waste is already well established in most disposal programmes. Numerous studies on bentonites, focussing on bentonite interaction with other components of the engineered barrier system and a range of host rock environments, are present in the literature. In this article, recent bentonite natural analogue studies are briefly reviewed, and gaps in the current literature identified, with the aim of (1) suggesting where relevant new information could be obtained by data mining published bentonite natural analogue studies with a new focus on current safety case requirements, (2) collecting relevant information by revisiting known bentonite analogue sites and conducting investigations with more appropriate analytical techniques, and (3) identifying novel study sites where, for example, bentonite longevity in very dilute to highly saline groundwater conditions can be studied. It must be noted that the use of natural analogues in safety case development is likely to be site and repository design-specific in nature and thus emphasis is placed on the appropriate use of relevant natural analogue data on bentonite longevity. (authors)

  7. Homozygosity of single nucleotide polymorphisms in the 3' region of the canine estrogen receptor 1 gene is greater in Toy Poodles than in Miniature Dachshunds and Chihuahuas.

    Science.gov (United States)

    Pathirana, Indunil N; Tanaka, Kakeru; Kawate, Noritoshi; Tsuji, Makoto; Hatoya, Shingo; Inaba, Toshio; Tamada, Hiromichi

    2011-06-01

    Differences in the distribution of single nucleotide polymorphisms (SNPs) and haplotypes in the estrogen receptor α gene (ESR1) were examined in Miniature Dachshunds (n = 48), Chihuahuas (n = 20) and Toy Poodles (n = 18). Five DNA fragments located in the 40-kb region at the 3' end of ESR1 were amplified by polymerase chain reaction and were directly sequenced. We compared allele, genotype and estimated haplotype frequencies at each SNP in the 3' end of ESR1 for these three breeds of small dog. The frequency of the major allele and the genotype frequency of the major allele homozygotes, were significantly higher in Toy Poodles for five SNPs (SNP #5, #14-17) than in Miniature Dachshunds, and significantly higher in Toy Poodles than Chihuahuas for three SNPs (SNP #15-17). A common haplotype block was identified in an approximately 20-kb region encompassing four SNPs (SNPs # 14-17). The frequencies of the most abundant estimated haplotype (GTTG) and GTTG homozygotes were significantly higher in Toy Poodles than in the other two breeds. These results imply that homozygosity for the allele, genotype and haplotype distribution within the block at the 3' end of ESR1 is greater in Toy Poodles than in Miniature Dachshunds and Chihuahuas. © 2011 The Authors; Animal Science Journal © 2011 Japanese Society of Animal Science.

  8. A Comparison of Angular Values of the Pelvic Limb with Normal and Medial Patellar Luxation Stifles in Chihuahua Dogs Using Radiography and Computed Tomography.

    Science.gov (United States)

    Phetkaew, Thitaporn; Kalpravidh, Marissak; Penchome, Rampaipat; Wangdee, Chalika

    2018-02-01

     This article aimed to determine and compare the angular values of the pelvic limb in normal and medial patellar luxation (MPL) stifles in Chihuahuas using radiography and computed tomographic (CT) scan, to identify the relationship between pelvic limb angles and severity of MPL. In addition, radiographic and CT images were compared to determine the more suitable method of limb deformity assessment.  Sixty hindlimbs of Chihuahuas were divided into normal and grade 1, 2, 3 and 4 MPL groups. The pelvic limb angles in frontal and sagittal planes were evaluated on radiography and CT scan. Femoral and tibial torsion angles (FTA and TTA) were evaluated only by CT scan. All angles were compared among normal and MPL stifles and between radiography and CT scan.  Based on the CT scan, the mechanical lateral distal femoral angle (mLDFA), anatomical caudal proximal femoral angle (aCdPFA), and TTA were related to the severity of MPL. The mLDFA and TTA were significantly increased ( p  Chihuahuas are aLDFA, mLDFA, aCdPFA and TTA. Radiography had some limitations for evaluating pelvic limb angles. The caudocranial radiograph is recommended for the assessment of the distal femoral angles, while the craniocaudal radiograph is for the tibial angles. Schattauer GmbH Stuttgart.

  9. Real-time PCR genotyping assay for canine progressive rod-cone degeneration and mutant allele frequency in Toy Poodles, Chihuahuas and Miniature Dachshunds in Japan.

    Science.gov (United States)

    Kohyama, Moeko; Tada, Naomi; Mitsui, Hiroko; Tomioka, Hitomi; Tsutsui, Toshihiko; Yabuki, Akira; Rahman, Mohammad Mahbubur; Kushida, Kazuya; Mizukami, Keijiro; Yamato, Osamu

    2016-03-01

    Canine progressive rod-cone degeneration (PRCD) is a middle- to late-onset, autosomal recessive, inherited retinal disorder caused by a substitution (c.5G>A) in the canine PRCD gene that has been identified in 29 or more purebred dogs. In the present study, a TaqMan probe-based real-time PCR assay was developed and evaluated for rapid genotyping and large-scale screening of the mutation. Furthermore, a genotyping survey was carried out in a population of the three most popular breeds in Japan (Toy Poodles, Chihuahuas and Miniature Dachshunds) to determine the current mutant allele frequency. The assay separated all the genotypes of canine PRCD rapidly, indicating its suitability for large-scale surveys. The results of the survey showed that the mutant allele frequency in Toy Poodles was high enough (approximately 0.09) to allow the establishment of measures for the prevention and control of this disorder in breeding kennels. The mutant allele was detected in Chihuahuas for the first time, but the frequency was lower (approximately 0.02) than that in Toy Poodles. The mutant allele was not detected in Miniature Dachshunds. This assay will allow the selective breeding of dogs from the two most popular breeds (Toy Poodle and Chihuahua) in Japan and effective prevention or control of the disorder.

  10. Alligator Rivers Analogue project. Application of scenario development method in evaluation of the Koongarra Analogue. Final Report - Volume 16

    Energy Technology Data Exchange (ETDEWEB)

    Skagius, K. [Kemakta Consultants co., Stockholm (Sweden); Wingefors, S. [Swedish Nuclear Power Inspectorate, Stockholm (Sweden)

    1992-12-31

    The study of natural analogues has been established as one of the most important methods for validation of concepts and models applied for the assessment of long-term performance of repositories for nuclear waste. The objectives of such studies range from detailed investigations of processes and features on a small scale to attempts of explaining the evolution of whole sites. For studies of specific processes it may well be as important to consider the larger scale settings as boundary conditions. This appreciation of context and an integrated view may be as important for evaluation of most natural analogues as for performance assessments. This is more evident the more the evaluation depends on a knowledge about the evolution of the natural analogue. The attempted formulation of scenarios of the Koongarra Analogue has been based on the external conditions and external features. A rapid weathering of the host rock, i.e. the chlorite schist, is assumed to have started around the onset of the Pleistocene Ice Age (ca 1.6 Ma BP). The eventual oxidation and mobilization of the uranium ore could then have occurred under unsaturated or saturated conditions. This leads to the following major scenarios: (1) Uranyl Phosphates formed under unsaturated conditions, with a periodical evolution of the dispersion fan in conjunction with alternating dry (glacial) and wet (interglacial) periods during the Pleistocene Ice Age; (2) Uranyl Phosphates formed under unsaturated conditions as a single event, taking place either early or late during the Pleistocene Ice Age; (3)Uranyl Phosphates formed under saturated conditions, in conjunction with periods of higher and lower flow due to the climatic cycling. Although the original objectives may not have been fully achieved, this work is believed to contribute to a better understanding of the Koongarra Analogue as well as to give a basis for further scenario work

  11. Alligator Rivers Analogue project. Application of scenario development method in evaluation of the Koongarra Analogue. Final Report - Volume 16

    International Nuclear Information System (INIS)

    Skagius, K.; Wingefors, S.

    1992-01-01

    The study of natural analogues has been established as one of the most important methods for validation of concepts and models applied for the assessment of long-term performance of repositories for nuclear waste. The objectives of such studies range from detailed investigations of processes and features on a small scale to attempts of explaining the evolution of whole sites. For studies of specific processes it may well be as important to consider the larger scale settings as boundary conditions. This appreciation of context and an integrated view may be as important for evaluation of most natural analogues as for performance assessments. This is more evident the more the evaluation depends on a knowledge about the evolution of the natural analogue. The attempted formulation of scenarios of the Koongarra Analogue has been based on the external conditions and external features. A rapid weathering of the host rock, i.e. the chlorite schist, is assumed to have started around the onset of the Pleistocene Ice Age (ca 1.6 Ma BP). The eventual oxidation and mobilization of the uranium ore could then have occurred under unsaturated or saturated conditions. This leads to the following major scenarios: (1) Uranyl Phosphates formed under unsaturated conditions, with a periodical evolution of the dispersion fan in conjunction with alternating dry (glacial) and wet (interglacial) periods during the Pleistocene Ice Age; (2) Uranyl Phosphates formed under unsaturated conditions as a single event, taking place either early or late during the Pleistocene Ice Age; (3)Uranyl Phosphates formed under saturated conditions, in conjunction with periods of higher and lower flow due to the climatic cycling. Although the original objectives may not have been fully achieved, this work is believed to contribute to a better understanding of the Koongarra Analogue as well as to give a basis for further scenario work

  12. Alligator Rivers Analogue project. Application of scenario development method in evaluation of the Koongarra Analogue. Final Report - Volume 16

    Energy Technology Data Exchange (ETDEWEB)

    Skagius, K [Kemakta Consultants co., Stockholm (Sweden); Wingefors, S [Swedish Nuclear Power Inspectorate, Stockholm (Sweden)

    1993-12-31

    The study of natural analogues has been established as one of the most important methods for validation of concepts and models applied for the assessment of long-term performance of repositories for nuclear waste. The objectives of such studies range from detailed investigations of processes and features on a small scale to attempts of explaining the evolution of whole sites. For studies of specific processes it may well be as important to consider the larger scale settings as boundary conditions. This appreciation of context and an integrated view may be as important for evaluation of most natural analogues as for performance assessments. This is more evident the more the evaluation depends on a knowledge about the evolution of the natural analogue. The attempted formulation of scenarios of the Koongarra Analogue has been based on the external conditions and external features. A rapid weathering of the host rock, i.e. the chlorite schist, is assumed to have started around the onset of the Pleistocene Ice Age (ca 1.6 Ma BP). The eventual oxidation and mobilization of the uranium ore could then have occurred under unsaturated or saturated conditions. This leads to the following major scenarios: (1) Uranyl Phosphates formed under unsaturated conditions, with a periodical evolution of the dispersion fan in conjunction with alternating dry (glacial) and wet (interglacial) periods during the Pleistocene Ice Age; (2) Uranyl Phosphates formed under unsaturated conditions as a single event, taking place either early or late during the Pleistocene Ice Age; (3)Uranyl Phosphates formed under saturated conditions, in conjunction with periods of higher and lower flow due to the climatic cycling. Although the original objectives may not have been fully achieved, this work is believed to contribute to a better understanding of the Koongarra Analogue as well as to give a basis for further scenario work

  13. Field studies about radionuclide migration natural analogues and faults in clays

    International Nuclear Information System (INIS)

    Williams, G.M.; Hooker, P.J.; Brightman, M.A.

    1990-01-01

    This report puts together final reports of CEC contracts about the following topics: in situ determination of the effects of organics on the mobility of radionuclides in controlled conditions of groundwater flow (Drigg site); natural analogue studies of radionuclide migration (Loch Lomond, Broubster, Needle's Eye); faults in clays: their detection and characterization (Down Ampney site)

  14. PTAL Database and Website: Developing a Novel Information System for the Scientific Exploitation of the Planetary Terrestrial Analogues Library

    Science.gov (United States)

    Veneranda, M.; Negro, J. I.; Medina, J.; Rull, F.; Lantz, C.; Poulet, F.; Cousin, A.; Dypvik, H.; Hellevang, H.; Werner, S. C.

    2018-04-01

    The PTAL website will store multispectral analysis of samples collected from several terrestrial analogue sites and pretend to become a cornerstone tool for the scientific community interested in deepening the knowledge on Mars geological processes.

  15. The ketamine analogue methoxetamine and 3- and 4-methoxy analogues of phencyclidine are high affinity and selective ligands for the glutamate NMDA receptor.

    Directory of Open Access Journals (Sweden)

    Bryan L Roth

    Full Text Available In this paper we determined the pharmacological profiles of novel ketamine and phencyclidine analogues currently used as 'designer drugs' and compared them to the parent substances via the resources of the National Institute of Mental Health Psychoactive Drug Screening Program. The ketamine analogues methoxetamine ((RS-2-(ethylamino-2-(3-methoxyphenylcyclohexanone and 3-MeO-PCE (N-ethyl-1-(3-methoxyphenylcyclohexanamine and the 3- and 4-methoxy analogues of phencyclidine, (1-[1-(3-methoxyphenylcyclohexyl]piperidine and 1-[1-(4-methoxyphenylcyclohexyl]piperidine, were all high affinity ligands for the PCP-site on the glutamate NMDA receptor. In addition methoxetamine and PCP and its analogues displayed appreciable affinities for the serotonin transporter, whilst the PCP analogues exhibited high affinities for sigma receptors. Antagonism of the NMDA receptor is thought to be the key pharmacological feature underlying the actions of dissociative anaesthetics. The novel ketamine and PCP analogues had significant affinities for the NMDA receptor in radioligand binding assays, which may explain their psychotomimetic effects in human users. Additional actions on other targets could be important for delineating side-effects.

  16. Chemistry of fluids from a natural analogue for a geological CO{sub 2} storage site (Montmiral, France): Lessons for CO{sub 2}-water-rock interaction assessment and monitoring

    Energy Technology Data Exchange (ETDEWEB)

    Pauwels, Helene [BRGM - Water Division, 3, av Claude Guillemin, 45060 Orleans Cedex (France)], E-mail: h.pauwels@brgm.fr; Gaus, Irina; Le Nindre, Yves Michel [BRGM - Water Division, 3, av Claude Guillemin, 45060 Orleans Cedex (France); Pearce, Jonathan [British Geological Survey, Kingsley Dunham Centre, Keyworth, Nottingham NG125GG (United Kingdom); Czernichowski-Lauriol, Isabelle [BRGM - Water Division, 3, av Claude Guillemin, 45060 Orleans Cedex (France)

    2007-12-15

    these elements in the brine, which are attributed to CO{sub 2} interactions, illustrate the relevance of monitoring the water quality at future industrial CO{sub 2} storage sites.

  17. CO2 Capture with Enzyme Synthetic Analogue

    Energy Technology Data Exchange (ETDEWEB)

    Cordatos, Harry

    2010-11-08

    Overview of an ongoing, 2 year research project partially funded by APRA-E to create a novel, synthetic analogue of carbonic anhydrase and incorporate it into a membrane for removal of CO2 from flue gas in coal power plants. Mechanism background, preliminary feasibility study results, molecular modeling of analogue-CO2 interaction, and program timeline are provided.

  18. Synthesis and anticancer evaluation of spermatinamine analogues

    KAUST Repository

    Moosa, Basem; Sagar, Sunil; Li, Song; Esau, Luke; Kaur, Mandeep; Khashab, Niveen M.

    2016-01-01

    analogues and their cytotoxic evaluation against three human cancer cell lines i.e. cervix adenocarcinoma (HeLa), breast adenocarcinoma (MCF-7), and prostate carcinoma (DU145). Analogues 12, 14 and 15 were found to be the most potent against one or more cell

  19. Cyprus natural analogue project (CNAP). Phase II Final Report

    International Nuclear Information System (INIS)

    Alexander, W.R.; Milodowski, A.E.

    2011-02-01

    Due to the extremely slow kinetics of bentonite reaction in low alkali cement leachates, natural analogues would appear to be the only viable method of studying bentonite reaction. As a result of a review of the available literature, several sites in Cyprus were selected as particularly promising for this purpose. This report presents the results of two short field campaigns in Cyprus in November/December, 2008 and February, 2009. The main aim of these campaigns was to establish if appropriate sites existed for a natural analogue study of bentonite-low alkali cement leachate reaction. Focus is on mineralogical changes and not changes in physical properties (such as porosity and permeability) of bentonite as the industrially-processed bentonite used in a repository will be completely different in terms of its engineering and hydrogeological properties to the unprocessed natural bentonite or analogue smectite-rich materials. The first campaign was in the form of a reconnaissance study to identify sites of likely interest and the second, follow-up, campaign focussed on obtaining preliminary groundwater and solid phase (bentonites/clay-rich sediments/altered igneous rocks/soils) samples which would allow a more detailed assessment of several of the potential sites. A large amount of information was collected during these short field campaigns and subsequent laboratory analysis of the collected samples so, to keep the main report down to a digestible size, much of the supporting information has been collated in seven appendices. These include full details of all 30 sites visited during both campaigns along with sample details, information on the analytical techniques, the analytical raw data and numerous photographs of the sites. The intention is that this report will provide full supporting information for a potential Phase III and a detailed database for our colleagues at the Geological Survey Department (GSD) in Cyprus. Consequently, all the information acquired

  20. The Greenland Analogue Project. Yearly Report 2009

    Energy Technology Data Exchange (ETDEWEB)

    2010-12-15

    A deep geological repository for spent nuclear fuel needs to be designed to keep used nuclear fuel isolated from mankind and the environment for a million years. Within this time frame glacial conditions are expected in regions that have been glaciated in the past two to ten million years. Climate induced changes such as the growth of ice sheets and permafrost will influence and alter the ground surface and subsurface environment, including its hydrology, which may impact repository safety. Glaciation impact assessments have to-date used over-simplified models and conservative assumptions, for example in the representation of ice sheet hydrology, that do not reflect the complexity of natural systems and processes. This is largely due to lack of direct observations of such processes from existing ice sheets, which if more readily available could help reduce uncertainties and provide a strong scientific basis for the treatment of glacial impacts in safety assessments. Our current understanding of the hydrological, hydrogeological and hydrogeochemical processes associated with glacial cycles and their impact on the long-term performance of deep geological repositories for spent nuclear fuel will be significantly improved by studying a modern analogue. To advance the understanding of processes associated with glaciation and their impact on the long-term performance of a deep geological repository, the Greenland Analogue Project (GAP), a four-year field and modelling study of the Greenland ice sheet and sub-surface conditions, has been initiated collaboratively by SKB, Posiva and NWMO. The study site encompasses a land terminus portion of the Greenland ice sheet east of Kangerlussuaq and is in many ways considered to be an appropriate analogue of the conditions that are expected to prevail in much of Canada and Fennoscandia during future glacial cycles. The project is planned to run from 2009 until 2012. The GAP will conduct the first in situ investigations of some of

  1. The Greenland Analogue Project. Yearly Report 2009

    International Nuclear Information System (INIS)

    2010-12-01

    A deep geological repository for spent nuclear fuel needs to be designed to keep used nuclear fuel isolated from mankind and the environment for a million years. Within this time frame glacial conditions are expected in regions that have been glaciated in the past two to ten million years. Climate induced changes such as the growth of ice sheets and permafrost will influence and alter the ground surface and subsurface environment, including its hydrology, which may impact repository safety. Glaciation impact assessments have to-date used over-simplified models and conservative assumptions, for example in the representation of ice sheet hydrology, that do not reflect the complexity of natural systems and processes. This is largely due to lack of direct observations of such processes from existing ice sheets, which if more readily available could help reduce uncertainties and provide a strong scientific basis for the treatment of glacial impacts in safety assessments. Our current understanding of the hydrological, hydrogeological and hydrogeochemical processes associated with glacial cycles and their impact on the long-term performance of deep geological repositories for spent nuclear fuel will be significantly improved by studying a modern analogue. To advance the understanding of processes associated with glaciation and their impact on the long-term performance of a deep geological repository, the Greenland Analogue Project (GAP), a four-year field and modelling study of the Greenland ice sheet and sub-surface conditions, has been initiated collaboratively by SKB, Posiva and NWMO. The study site encompasses a land terminus portion of the Greenland ice sheet east of Kangerlussuaq and is in many ways considered to be an appropriate analogue of the conditions that are expected to prevail in much of Canada and Fennoscandia during future glacial cycles. The project is planned to run from 2009 until 2012. The GAP will conduct the first in situ investigations of some of

  2. La violencia en la región noroeste de Chihuahua. Experiencias e impactos desde la comunidad educativa

    Directory of Open Access Journals (Sweden)

    Marcos J. Estrada Ruiz

    2013-01-01

    Full Text Available La violencia escolar ha sido un tema explorado de manera importante en los últimos años desde la investigación educativa en México, sin embargo, en contextos de alta violencia no se han mostrado los impactos de la violencia extraescolar y estructural, en la escuela y en otros espacios comunitarios. El artículo presenta resultados de una investigación que tuvo por objetivo reconstruir el impacto de la violencia en la región noroeste de Chihuahua, desde la comunidad educativa (docentes, padres, estudiantes de dos municipios en particular. A la manera de estudios en caso y recurriendo al análisis de contenido, se analizanlos impactos en la percepción del incremento de la violencia a partir de la experiencia directa; la modificación de la dinámica de las escuelas; el abandono de los espacios públicos y el señalamiento de “nuevos” actores, aparentemente ajenos a la comunidad, que aparecen a priori por su condición social, como los responsables de la violencia.

  3. Baccharis Salicifolia development in the presence of high concentrations of uranium in the arid environment of San Marcos, Chihuahua

    Energy Technology Data Exchange (ETDEWEB)

    Luna P, M. Y.; Alarcon H, M. T.; Silva S, M.; Renteria V, M; Rodriguez V, M. A.; Herrera P, E.; Reyes C, M.; Montero C, M. E., E-mail: elena.montero@cimav.edu.m [Centro de Investigacion en Materiales Avanzados, S. C., Miguel de Cervantes 120, Complejo Industrial Chihuahua, 31109 Chihuahua (Mexico)

    2011-02-15

    In humid zones and marine environments the bio indicator contaminants by trace elements are well established. However, in arid zones it is more difficult to find these tools because there is less biodiversity. The objective of this paper was to analyze the behavior of the Baccharis salicifolia plant in areas with high uranium concentration in arid zones, to determine the characteristics of tolerance and possible use as a bio monitor for the presence of such contaminants. For this project a uraniferous zone was selected in San Marcos, located northwest of the City of Chihuahua. A total of 8 sampling points of the plant and soil were located here. Each sample was divided into the root and the stem and leaves to determine the specific activity of the uranium in both parts of the plant and its sediments. The determination of the specific activities of the total uranium in the samples was obtained by liquid scintillation with alpha-beta separation. The results indicate a tendency for the plant to accumulate the uranium in its different parts, and to trans locate it to its stem and leaves. The plant is resistant to high concentrations of uranium, not showing any specific changes in relation to non contaminated areas that might indicate the presence of the contaminant. Therefore, its use as a bio monitor species is limited. (Author)

  4. Baccharis Salicifolia development in the presence of high concentrations of uranium in the arid environment of San Marcos, Chihuahua

    International Nuclear Information System (INIS)

    Luna P, M. Y.; Alarcon H, M. T.; Silva S, M.; Renteria V, M; Rodriguez V, M. A.; Herrera P, E.; Reyes C, M.; Montero C, M. E.

    2011-01-01

    In humid zones and marine environments the bio indicator contaminants by trace elements are well established. However, in arid zones it is more difficult to find these tools because there is less biodiversity. The objective of this paper was to analyze the behavior of the Baccharis salicifolia plant in areas with high uranium concentration in arid zones, to determine the characteristics of tolerance and possible use as a bio monitor for the presence of such contaminants. For this project a uraniferous zone was selected in San Marcos, located northwest of the City of Chihuahua. A total of 8 sampling points of the plant and soil were located here. Each sample was divided into the root and the stem and leaves to determine the specific activity of the uranium in both parts of the plant and its sediments. The determination of the specific activities of the total uranium in the samples was obtained by liquid scintillation with alpha-beta separation. The results indicate a tendency for the plant to accumulate the uranium in its different parts, and to trans locate it to its stem and leaves. The plant is resistant to high concentrations of uranium, not showing any specific changes in relation to non contaminated areas that might indicate the presence of the contaminant. Therefore, its use as a bio monitor species is limited. (Author)

  5. Synthesis and biological evaluation of febrifugine analogues.

    Science.gov (United States)

    Mai, Huong Doan Thi; Thanh, Giang Vo; Tran, Van Hieu; Vu, Van Nam; Vu, Van Loi; Le, Cong Vinh; Nguyen, Thuy Linh; Phi, Thi Dao; Truong, Bich Ngan; Chau, Van Minh; Pham, Van Cuong

    2014-12-01

    A series of febrifugine analogues were designed and synthesized. Antimalarial activity evaluation of the synthetic compounds indicated that these derivatives had a strong inhibition against both chloroquine-sensitive and -resistant Plasmodium falciparum parasites. Many of them were found to be more active than febrifugine hydrochloride. The tested analogues had also a significant cytotoxicity against four cancer cell lines (KB, MCF7, LU1 and HepG2). Among the synthetic analogues, two compounds 17b and 17h displayed a moderate cytotoxicity while they exhibited a remarkable antimalarial activity.

  6. Antimicrobial Activity of Resveratrol Analogues

    Directory of Open Access Journals (Sweden)

    Malik Chalal

    2014-06-01

    Full Text Available Stilbenes, especially resveratrol and its derivatives, have become famous for their positive effects on a wide range of medical disorders, as indicated by a huge number of published studies. A less investigated area of research is their antimicrobial properties. A series of 13 trans-resveratrol analogues was synthesized via Wittig or Heck reactions, and their antimicrobial activity assessed on two different grapevine pathogens responsible for severe diseases in the vineyard. The entire series, together with resveratrol, was first evaluated on the zoospore mobility and sporulation level of Plasmopara viticola (the oomycete responsible for downy mildew. Stilbenes displayed a spectrum of activity ranging from low to high. Six of them, including the most active ones, were subsequently tested on the development of Botrytis cinerea (fungus responsible for grey mold. The results obtained allowed us to identify the most active stilbenes against both grapevine pathogens, to compare the antimicrobial activity of the evaluated series of stilbenes, and to discuss the relationship between their chemical structure (number and position of methoxy and hydroxy groups and antimicrobial activity.

  7. Condensed matter analogues of cosmology

    Science.gov (United States)

    Kibble, Tom; Srivastava, Ajit

    2013-10-01

    It is always exciting when developments in one branch of physics turn out to have relevance in a quite different branch. It would be hard to find two branches farther apart in terms of energy scales than early-universe cosmology and low-temperature condensed matter physics. Nevertheless ideas about the formation of topological defects during rapid phase transitions that originated in the context of the very early universe have proved remarkably fruitful when applied to a variety of condensed matter systems. The mathematical frameworks for describing these systems can be very similar. This interconnection has led to a deeper understanding of the phenomena in condensed matter systems utilizing ideas from cosmology. At the same time, one can view these condensed matter analogues as providing, at least in a limited sense, experimental access to the phenomena of the early universe for which no direct probe is possible. As this special issue well illustrates, this remains a dynamic and exciting field. The basic idea is that when a system goes through a rapid symmetry-breaking phase transition from a symmetric phase into one with spontaneously broken symmetry, the order parameter may make different choices in different regions, creating domains that when they meet can trap defects. The scale of those domains, and hence the density of defects, is constrained by the rate at which the system goes through the transition and the speed with which order parameter information propagates. This is what has come to be known as the Kibble-Zurek mechanism. The resultant scaling laws have now been tested in a considerable variety of different systems. The earliest experiments illustrating the analogy between cosmology and condensed matter were in liquid crystals, in particular on the isotropic-to-nematic transition, primarily because it is very easy to induce the phase transition (typically at room temperature) and to image precisely what is going on. This field remains one of the

  8. Field Exploration and Life Detection Sampling for Planetary Analogue Research (FELDSPAR): Variability and Correlation in Biomarker and Mineralogy Measurements from Icelandic Mars Analogues

    Science.gov (United States)

    Gentry, D.; Amador, E.; Cable, M. L.; Cantrell, T.; Chaudry, N.; Cullen, T.; Duca, Z.; Jacobsen, M.; Kirby, J.; McCaig, H.; hide

    2018-01-01

    In situ exploration of planetary environments allows biochemical analysis of sub-centimeter-scale samples; however, landing sites are selected a priori based on measurable meter- to kilometer-scale geological features. Optimizing life detection mission science return requires both understanding the expected biomarker distributions across sample sites at different scales and efficiently using first-stage in situ geochemical instruments to justify later-stage biological or chemical analysis. Icelandic volcanic regions have an extensive history as Mars analogue sites due to desiccation, low nutrient availability, and temperature extremes, in addition to the advantages of geological youth and isolation from anthropogenic contamination. Many Icelandic analogue sites are also rugged and remote enough to create the same type of instrumentation and sampling constraints typically faced by robotic exploration.

  9. Rethinking of the criteria for natural analogue study. A case of Tono natural analogue study

    International Nuclear Information System (INIS)

    Yoshida, Hidekazu

    1996-01-01

    Natural analogue regarding long-term performance of the geological disposal system for radioactive waste isolation is essentially the study of geochemical process which has been evolved in geological environment. All geochemical studies, however, will not be nominated as natural analogue studies. It is, therefore, important to be clear the criteria for natural analogue study with the view of analogy by following three categories, (1) Conceptual model development, (2) Data provision and (3) Model testing, for the concept of geological disposal and safety assessment model. Rethinking of the criteria for natural analogue study through the case of Tono Natural Analogue Study, and the usefulness of natural analogue study for the safety assessment of geological disposal system in Japan have been presented in this paper. (author)

  10. STRATIGRAPHY OF THE PB-1 WELL, NOPAL I URANIUM DEPOSIT, SIERRA PENA BLANCA, CHIHUAHUA, MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    NA

    2005-06-25

    Three wells, PB-1, PB-2, and PB-3, were drilled in 2003 at the Nopal I uranium deposit as part of a natural analogue study to evaluate radionuclide transport processes. The wells penetrate through the Tertiary volcanic section down to the Cretaceous limestone basement, and intersect the top of the regional aquifer system. The PB-1 well, drilled immediately adjacent to the Nopal I ore body, was cored to a depth of 250 m, thus providing an opportunity to document the local stratigraphy. The uppermost unit encountered in the PB-1 well is the Nopal Formation, a densely welded, crystal-rich rhyolitic ash-flow tuff. The cored section is highly altered and devitrified, with kaolinite, quartz, chlorite, and montmorillonite replacing feldspars and much of the groundmass. Breccia zones within the tuff contain fracture fillings of hematite, limonite, and goethite. A zone of intense clay alteration encountered in the depth interval 17.45-22.30 m was interpreted to represent the basal vitrophyre of this unit. Underlying the basal vitrophyre is the Coloradas Formation, which consists of a welded, lithic-rich rhyolitic ash-flow tuff. The cored section of this unit has undergone devitrification and oxidation, and has a similar alteration mineralogy to that observed in the Nopal tuff. The Nopal I ore body is restricted to a brecciated zone that intersects these two volcanic units. A sharp contact between the Coloradas tuff and the underlying Pozos Formation was observed at a depth of 136.38 m. The Pozos Formation in the PB-1 core consists of interbedded, poorly sorted sandstone and conglomerate layers. The conglomeratic clasts consist of subangular to subrounded fragments of volcanic rocks, limestone, and chert. Thin (2-6 m) intervals of intercalated pumiceous tuffs were observed within this unit. The contact between the Pozos Formation and the underlying Cretaceous limestone basement was observed at a depth of 244.4 m.

  11. STRATIGRAPHY OF THE PB-1 WELL, NOPAL I URANIUM DEPOSIT, SIERRA PENA BLANCA, CHIHUAHUA, MEXICO

    International Nuclear Information System (INIS)

    2005-01-01

    Three wells, PB-1, PB-2, and PB-3, were drilled in 2003 at the Nopal I uranium deposit as part of a natural analogue study to evaluate radionuclide transport processes. The wells penetrate through the Tertiary volcanic section down to the Cretaceous limestone basement, and intersect the top of the regional aquifer system. The PB-1 well, drilled immediately adjacent to the Nopal I ore body, was cored to a depth of 250 m, thus providing an opportunity to document the local stratigraphy. The uppermost unit encountered in the PB-1 well is the Nopal Formation, a densely welded, crystal-rich rhyolitic ash-flow tuff. The cored section is highly altered and devitrified, with kaolinite, quartz, chlorite, and montmorillonite replacing feldspars and much of the groundmass. Breccia zones within the tuff contain fracture fillings of hematite, limonite, and goethite. A zone of intense clay alteration encountered in the depth interval 17.45-22.30 m was interpreted to represent the basal vitrophyre of this unit. Underlying the basal vitrophyre is the Coloradas Formation, which consists of a welded, lithic-rich rhyolitic ash-flow tuff. The cored section of this unit has undergone devitrification and oxidation, and has a similar alteration mineralogy to that observed in the Nopal tuff. The Nopal I ore body is restricted to a brecciated zone that intersects these two volcanic units. A sharp contact between the Coloradas tuff and the underlying Pozos Formation was observed at a depth of 136.38 m. The Pozos Formation in the PB-1 core consists of interbedded, poorly sorted sandstone and conglomerate layers. The conglomeratic clasts consist of subangular to subrounded fragments of volcanic rocks, limestone, and chert. Thin (2-6 m) intervals of intercalated pumiceous tuffs were observed within this unit. The contact between the Pozos Formation and the underlying Cretaceous limestone basement was observed at a depth of 244.4 m

  12. International video project on natural analogues

    International Nuclear Information System (INIS)

    Guentensperger, Marcel

    1993-01-01

    A natural analogue can be defined as a natural process which has occurred in the past and is studied in order to test predictions about the future evolution of similar processes. In recent years, natural analogues have been used increasingly to test the mathematical models required for repository performance assessment. Analogues are, however, also of considerable use in public relations as they allow many of the principles involved in demonstrating repository safety to be illustrated in a clear manner using natural systems with which man is familiar. The international Natural Analogue Working Group (NAWG), organised under the auspices of the CEC, has recognised that such PR applications are of considerable importance and should be supported from a technical level. At the NAWG meeting in Pitlochry, Scotland (June 1990), it was recommended that the possibilities for making a video film on this topic be investigated and Nagra was requested to take the lead role in setting up such a project

  13. Natural analogues and radionuclide transport model validation

    International Nuclear Information System (INIS)

    Lever, D.A.

    1987-08-01

    In this paper, some possible roles for natural analogues are discussed from the point of view of those involved with the development of mathematical models for radionuclide transport and with the use of these models in repository safety assessments. The characteristic features of a safety assessment are outlined in order to address the questions of where natural analogues can be used to improve our understanding of the processes involved and where they can assist in validating the models that are used. Natural analogues have the potential to provide useful information about some critical processes, especially long-term chemical processes and migration rates. There is likely to be considerable uncertainty and ambiguity associated with the interpretation of natural analogues, and thus it is their general features which should be emphasized, and models with appropriate levels of sophistication should be used. Experience gained in modelling the Koongarra uranium deposit in northern Australia is drawn upon. (author)

  14. The Planetary Terrestrial Analogues Library (PTAL)

    Science.gov (United States)

    Werner, S. C.; Dypvik, H.; Poulet, F.; Rull Perez, F.; Bibring, J.-P.; Bultel, B.; Casanova Roque, C.; Carter, J.; Cousin, A.; Guzman, A.; Hamm, V.; Hellevang, H.; Lantz, C.; Lopez-Reyes, G.; Manrique, J. A.; Maurice, S.; Medina Garcia, J.; Navarro, R.; Negro, J. I.; Neumann, E. R.; Pilorget, C.; Riu, L.; Sætre, C.; Sansano Caramazana, A.; Sanz Arranz, A.; Sobron Grañón, F.; Veneranda, M.; Viennet, J.-C.; PTAL Team

    2018-04-01

    The Planetary Terrestrial Analogues Library project aims to build and exploit a spectral data base for the characterisation of the mineralogical and geological evolution of terrestrial planets and small solar system bodies.

  15. Tidal regimes and salt marshes - the River Hamble analogue

    International Nuclear Information System (INIS)

    Gray, A.J.; Moy, I.L.; Warman, E.A.; Dawson, F.H.; Henville, P.

    1993-01-01

    Construction of estuarine tidal-energy barrages has a potentially major effect on the tidal regime of the estuary, particularly upstream of a barrage. Because tidal regime largely controls the distribution and species composition of intertidal plant and animal communities, it is important to understand how barrages may affect such communities. The main objectives of the research described in this report were to relate recent changes in tidal regime within an embanked area of salt marsh and mudflat to changes in the distribution of plant species. This was to test predictions about tidal control of species' range and to assess the site's suitability as an analogue of post-barrage conditions. (author)

  16. Astrobiology Field Research in Moon/Mars Analogue Environments: Preface

    Science.gov (United States)

    Foing, B. H.; Stoker, C.; Ehrenfreund, P.

    2011-01-01

    Extreme environments on Earth often provide similar terrain conditions to landing/operation sites on Moon and Mars. Several field campaigns (EuroGeoMars2009 and DOMMEX/ILEWG EuroMoonMars from November 2009 to March 2010) were conducted at the Mars Desert Research Station (MDRS) in Utah. Some of the key astrobiology results are presented in this special issue on Astrobiology field research in Moon/Mars analogue environments relevant to investigate the link between geology, minerals, organics and biota. Preliminary results from a multidisciplinary field campaign at Rio Tinto in Spain are presented.

  17. Craniometric Analysis of the Hindbrain and Craniocervical Junction of Chihuahua, Affenpinscher and Cavalier King Charles Spaniel Dogs With and Without Syringomyelia Secondary to Chiari-Like Malformation.

    Science.gov (United States)

    Knowler, Susan P; Kiviranta, Anna-Mariam; McFadyen, Angus K; Jokinen, Tarja S; La Ragione, Roberto M; Rusbridge, Clare

    2017-01-01

    To characterize and compare the phenotypic variables of the hindbrain and craniocervical junction associated with syringomyelia (SM) in the Chihuahua, Affenpinscher and Cavalier King Charles Spaniel (CKCS). Analysis of 273 T1-weighted mid-sagittal DICOM sequences of the hindbrain and craniocervical junction from 99 Chihuahuas, 42 Affenpinschers and 132 CKCSs. The study compared 22 morphometric features (11 lines, eight angles and three ratios) of dogs with and without SM using refined techniques based on previous studies of the Griffon Bruxellois (GB) using Discriminant Function Analysis and ANOVA with post-hoc corrections. The analysis identified 14/22 significant traits for SM in the three dog breeds, five of which were identical to those reported for the GB and suggest inclusion of a common aetiology. One ratio, caudal fossa height to the length of the skull base extended to an imaginary point of alignment between the atlas and supraoccipital bones, was common to all three breeds (p values 0.029 to Chihuahua had a smaller angle between the dens, atlas and basioccipital bone (p value < 0.001); Affenpinschers had a smaller distance from atlas to dens (p value 0.009); CKCS had a shorter distance between the spheno-occipital synchondrosis and atlas (p value 0.007). The selected morphometries successfully characterised conformational changes in the brain and craniocervical junction that might form the basis of a diagnostic tool for all breeds. The severity of SM involved a spectrum of abnormalities, incurred by changes in both angulation and size that could alter neural parenchyma compliance and/or impede cerebrospinal fluid channels.

  18. Craniometric Analysis of the Hindbrain and Craniocervical Junction of Chihuahua, Affenpinscher and Cavalier King Charles Spaniel Dogs With and Without Syringomyelia Secondary to Chiari-Like Malformation.

    Directory of Open Access Journals (Sweden)

    Susan P Knowler

    Full Text Available To characterize and compare the phenotypic variables of the hindbrain and craniocervical junction associated with syringomyelia (SM in the Chihuahua, Affenpinscher and Cavalier King Charles Spaniel (CKCS.Analysis of 273 T1-weighted mid-sagittal DICOM sequences of the hindbrain and craniocervical junction from 99 Chihuahuas, 42 Affenpinschers and 132 CKCSs. The study compared 22 morphometric features (11 lines, eight angles and three ratios of dogs with and without SM using refined techniques based on previous studies of the Griffon Bruxellois (GB using Discriminant Function Analysis and ANOVA with post-hoc corrections.The analysis identified 14/22 significant traits for SM in the three dog breeds, five of which were identical to those reported for the GB and suggest inclusion of a common aetiology. One ratio, caudal fossa height to the length of the skull base extended to an imaginary point of alignment between the atlas and supraoccipital bones, was common to all three breeds (p values 0.029 to <0.001. Associated with SM were a reduced occipital crest and two acute changes in angulation i 'sphenoid flexure' at the spheno-occipital synchondrosis ii 'cervical flexure' at the foramen magnum allied with medulla oblongata elevation. Comparing dogs with and without SM, each breed had a unique trait: Chihuahua had a smaller angle between the dens, atlas and basioccipital bone (p value < 0.001; Affenpinschers had a smaller distance from atlas to dens (p value 0.009; CKCS had a shorter distance between the spheno-occipital synchondrosis and atlas (p value 0.007.The selected morphometries successfully characterised conformational changes in the brain and craniocervical junction that might form the basis of a diagnostic tool for all breeds. The severity of SM involved a spectrum of abnormalities, incurred by changes in both angulation and size that could alter neural parenchyma compliance and/or impede cerebrospinal fluid channels.

  19. Development of a natural analogue database to support the safety case of the Korean radioactive waste disposal program

    Energy Technology Data Exchange (ETDEWEB)

    Baik, M.H.; Park, T.J.; Kim, I.Y.; Jeong, J. [Korea Atomic Research Institute, Yuseong-Gu, Daejeon (Korea, Republic of); Choi, K.W. [Korea Institute of Nuclear Safety, Yuseong-Gu, Daejeon (Korea, Republic of)

    2015-06-15

    In this study, the status of natural analogue studies in Korea is briefly summarized and applicability of existing natural analogue information to the Korean safety case has been evaluated. To enable effective application of natural analogue information to the overall evaluation of long-term safety (the 'safety case') for the geological disposal of radioactive wastes, a natural analogue database has been developed by collecting, classifying, and evaluating relevant data. The natural analogue data collected were classified into categories based on site information, components/processes of the disposal system, properties/phenomena, reference, safety case application, application method, and suitability to a safety case. Suitability of the natural analogue data to a specific safety case was evaluated based upon the importance and the applicability to the Korean safety case. As a result, 75 natural analogue datasets were selected as important for the Korean safety case. The database developed can now be utilized in the RD and D (Research, Development, and Demonstration) program development for natural analogue studies. In addition, the methodology developed and the database compiled in this study may assist in the development of safety case including safety assessment for high-level radioactive waste disposal in Korea as well as in other countries. (authors)

  20. Development of a natural analogue database to support the safety case of the Korean radioactive waste disposal program

    International Nuclear Information System (INIS)

    Baik, M.H.; Park, T.J.; Kim, I.Y.; Jeong, J.; Choi, K.W.

    2015-01-01

    In this study, the status of natural analogue studies in Korea is briefly summarized and applicability of existing natural analogue information to the Korean safety case has been evaluated. To enable effective application of natural analogue information to the overall evaluation of long-term safety (the 'safety case') for the geological disposal of radioactive wastes, a natural analogue database has been developed by collecting, classifying, and evaluating relevant data. The natural analogue data collected were classified into categories based on site information, components/processes of the disposal system, properties/phenomena, reference, safety case application, application method, and suitability to a safety case. Suitability of the natural analogue data to a specific safety case was evaluated based upon the importance and the applicability to the Korean safety case. As a result, 75 natural analogue datasets were selected as important for the Korean safety case. The database developed can now be utilized in the RD and D (Research, Development, and Demonstration) program development for natural analogue studies. In addition, the methodology developed and the database compiled in this study may assist in the development of safety case including safety assessment for high-level radioactive waste disposal in Korea as well as in other countries. (authors)

  1. Effect of the temperature on the sorption of cadmium in natural clinoptilolite from the State of Chihuahua; Efecto de la temperatura sobre la sorcion de cadmio en clinoptilolita natural del Estado de Chihuahua

    Energy Technology Data Exchange (ETDEWEB)

    Arambula V, V

    2004-07-01

    The investigation works related with the removal of cadmium of aqueous solutions, they make emphasis in a great number of materials that were used for this end, as well as in the parameters that influence, such as the temperature and the pH. In this work it was investigated the effect of the temperature on the removal of cadmium, using a zeolitic mineral native of the State of Chihuahua for they were determined it kinetic parameters, those diffusivity coefficients and the retention mechanisms (adsorption or ion exchange) involved. The clinoptilolite samples were characterized by means of scanning electron microscopy in high vacuum (MEB), elementary microanalysis (EDS) and X-ray diffraction (XRD). The experimental part consisted on putting in contact solutions of cadmium with the mineral, varying the temperature, the time of contact or the concentration; the quantification of sodium and cadmium in the liquid phase was carried out by means of atomic absorption spectroscopy (EAA). It was determined the time of equilibrium for the removal process. The temperature and the concentration influence on the process of sorption of cadmium in the zeolitic mineral (kinetics and isotherms). The kinetic model that describes better the sorption process of cadmium in the clinoptilolite was the pseudo-2 order. The apparent coefficient of diffusivity presented a greater value conforms to increment the temperature. The results of the isotherm of adsorption of cadmium presented a better adjustment to the Freundlich model. The quantity of cadmium retained by the mineral it was greater than the quantity of sodium found in the solution after the contact between the solution of cadmium and the zeolitic mineral and in accordance with the obtained separation factors, the natural zeolite shows a greater affinity for the cadmium that for the sodium ({alpha} > 1). (Author)

  2. The Greenland Analogue Project, Yearly Report 2009

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2011-08-15

    To advance the understanding of processes associated with glaciation and their impact on the long-term performance of a deep geological repository, the Greenland Analogue Project (GAP), a four-year field and modelling study of the Greenland ice sheet and sub-surface conditions, has been initiated collaboratively by SKB, Posiva and NWMO. The study site encompasses a land terminus portion of the Greenland ice sheet east of Kangerlussuaq and is in many ways considered to be an appropriate analogue of the conditions that are expected to prevail in much of Canada and Fennoscandia during future glacial cycles. The project is planned to run from 2009 until 2012. The GAP will conduct the first in situ investigations of some of the parameters and processes needed to achieve a realistic understanding of how an ice sheet may impact a deep repository, and will provide measurements, observations and data that may significantly improve our safety assessments and risk analyses of glaciation scenarios. The project includes three sub-projects (A-C) with specific individual objectives, which collectively aim at contributing knowledge and input to the overall project aim. Three field campaigns were carried out in SPA during 2009. These campaigns focused on: (1) deployment and maintenance of AWS and GPS stations and to test the deep-look radar equipment; (2) investigating the hydrological processes and feedbacks and testing of passive seismic equipment; (3) downloading of weather station data and GPS data and winterizing the equipment. An extensive archive of real-time satellite remote sensing datasets has been obtained to be able to better constraint the surface elevation and dynamics of basal hydrological mechanisms. From this archive it has been possible to obtain Russell Glacier Cachment (RGC)-wide constraints on annual, seasonal and specific temporal snapshots of surface speed, initial lake and moulin distribution, drainage and network connections along with the temporal

  3. The Greenland Analogue Project, Yearly Report 2009

    International Nuclear Information System (INIS)

    2011-08-01

    To advance the understanding of processes associated with glaciation and their impact on the long-term performance of a deep geological repository, the Greenland Analogue Project (GAP), a four-year field and modelling study of the Greenland ice sheet and sub-surface conditions, has been initiated collaboratively by SKB, Posiva and NWMO. The study site encompasses a land terminus portion of the Greenland ice sheet east of Kangerlussuaq and is in many ways considered to be an appropriate analogue of the conditions that are expected to prevail in much of Canada and Fennoscandia during future glacial cycles. The project is planned to run from 2009 until 2012. The GAP will conduct the first in situ investigations of some of the parameters and processes needed to achieve a realistic understanding of how an ice sheet may impact a deep repository, and will provide measurements, observations and data that may significantly improve our safety assessments and risk analyses of glaciation scenarios. The project includes three sub-projects (A-C) with specific individual objectives, which collectively aim at contributing knowledge and input to the overall project aim. Three field campaigns were carried out in SPA during 2009. These campaigns focused on: (1) deployment and maintenance of AWS and GPS stations and to test the deep-look radar equipment; (2) investigating the hydrological processes and feedbacks and testing of passive seismic equipment; (3) downloading of weather station data and GPS data and winterizing the equipment. An extensive archive of real-time satellite remote sensing datasets has been obtained to be able to better constraint the surface elevation and dynamics of basal hydrological mechanisms. From this archive it has been possible to obtain Russell Glacier Cachment (RGC)-wide constraints on annual, seasonal and specific temporal snapshots of surface speed, initial lake and moulin distribution, drainage and network connections along with the temporal

  4. La tecnificación del riego ante la escasez del agua para la generación de alimentos. Estudio de caso en Chihuahua, México

    OpenAIRE

    Olvera-Salgado, Maria Dolores; Investigadora del Instituto Mexicano de Tecnología del Agua, México.; Bahena-Delgado, Gregorio; Profesor de la Universidad Autónoma del Estado de Morelos-ipro. México.; Alpuche Garcés, Óscar; Profesor investigador de la Universidad Autónoma del Estado de Morelos; García Matías, Francisco; Profesor de la Universidad Autónoma del Estado de Morelos

    2014-01-01

    La investigación tuvo como objetivo analizar la productividad del agua y el impactode la tecnificación del riego sobre ella y el rendimiento de los cultivos comoprincipales aportadores de alimentos. Se realizó en el Distrito de Riego 005, Delicias,Chihuahua. Se usó el método comparativo para dos escenarios: el antes, como lacondición previa a la tecnificación del riego en el año 2003, caracterizada por unasuperficie con riego por gravedad, y el después en 2012-2013, en la superficie conriego ...

  5. INITIAL TEST WELL CONDITIONING AT NOPAL I URANIUM DEPOSIT, SIERRA PENA BLANCA, CHIHUAHUA, MEXICO

    Energy Technology Data Exchange (ETDEWEB)

    R.D. Oliver; J.C. Dinsmoor; S.J. Goldstein; I. Reyes; R. De La Garza

    2005-07-11

    Three test wells, PB-1, PB-2, and PB-3, were drilled at the Nopal I uranium deposit as part of a natural analogue study to evaluate radionuclide transport processes during March-April 2003. The initial pumping to condition the wells was completed during December 2003. The PB-1 well, drilled immediately adjacent to the Nopal I ore body, was continuously cored to a depth of 250 m, terminating 20 m below the top of the measured water level. The PB-2 and PB-3 wells, which were drilled on opposite sides of PB-1 at a radial distance of approximately 40 to 50 m outside of the remaining projected ore body, were also drilled to about 20 m below the top of the measured water level. Each test well was completed with 4-inch (10.2-cm) diameter PVC casing with a slotted liner below the water table. Initial conditioning of all three wells using a submersible pump at low pump rates [less than 1 gallon (3.8 1) per minute] resulted in measurable draw down and recoveries. The greatest drawdown ({approx}15 m) was observed in PB-2, whereas only minor (<1 m) drawdown occurred in PB-3. For PB-1 and PB-2, the water turbidity decreased as the wells were pumped and the pH values decreased, indicating that the contamination from the drilling fluid was reduced as the wells were conditioned. Test wells PB-1 and PB-2 showed increased inflow after several borehole volumes of fluid were removed, but their inflow rates remained less that the pumping rate. Test well PB-3 showed the smallest drawdown and least change in pH and conductivity during initial pumping and quickest recovery with a rise in measured water level after conditioning. The 195 gallons (750 l) of water pumped from PB-3 during conditioning was discharged through a household sponge. That sponge showed measurable gamma radiation, which decayed to background values in less than 12 hours. Preliminary interpretations include filtration of a radioisotope source with a short half-life or of a radioisotope that volatized as the sponge

  6. INITIAL TEST WELL CONDITIONING AT NOPAL I URANIUM DEPOSIT, SIERRA PENA BLANCA, CHIHUAHUA, MEXICO

    International Nuclear Information System (INIS)

    Oliver, R.D.; Dinsmoor, J.C.; Goldstein, S.J.; Reyes, I.; De La Garza, R.

    2005-01-01

    Three test wells, PB-1, PB-2, and PB-3, were drilled at the Nopal I uranium deposit as part of a natural analogue study to evaluate radionuclide transport processes during March-April 2003. The initial pumping to condition the wells was completed during December 2003. The PB-1 well, drilled immediately adjacent to the Nopal I ore body, was continuously cored to a depth of 250 m, terminating 20 m below the top of the measured water level. The PB-2 and PB-3 wells, which were drilled on opposite sides of PB-1 at a radial distance of approximately 40 to 50 m outside of the remaining projected ore body, were also drilled to about 20 m below the top of the measured water level. Each test well was completed with 4-inch (10.2-cm) diameter PVC casing with a slotted liner below the water table. Initial conditioning of all three wells using a submersible pump at low pump rates [less than 1 gallon (3.8 1) per minute] resulted in measurable draw down and recoveries. The greatest drawdown (∼15 m) was observed in PB-2, whereas only minor (<1 m) drawdown occurred in PB-3. For PB-1 and PB-2, the water turbidity decreased as the wells were pumped and the pH values decreased, indicating that the contamination from the drilling fluid was reduced as the wells were conditioned. Test wells PB-1 and PB-2 showed increased inflow after several borehole volumes of fluid were removed, but their inflow rates remained less that the pumping rate. Test well PB-3 showed the smallest drawdown and least change in pH and conductivity during initial pumping and quickest recovery with a rise in measured water level after conditioning. The 195 gallons (750 l) of water pumped from PB-3 during conditioning was discharged through a household sponge. That sponge showed measurable gamma radiation, which decayed to background values in less than 12 hours. Preliminary interpretations include filtration of a radioisotope source with a short half-life or of a radioisotope that volatized as the sponge dried

  7. Recombinant DNA derived monomeric insulin analogue: comparison with soluble human insulin in normal subjects.

    Science.gov (United States)

    Vora, J P; Owens, D R; Dolben, J; Atiea, J A; Dean, J D; Kang, S; Burch, A; Brange, J

    1988-11-12

    To compare the rate of absorption from subcutaneous tissue and the resulting hypoglycaemic effect of iodine-125 labelled soluble human insulin and a monomeric insulin analogue derived by recombinant DNA technology. Single blind randomised comparison of equimolar doses of 125I labelled soluble human insulin and insulin analogue. Study in normal people at a diabetes research unit and a university department of medical physics. Seven healthy male volunteers aged 20-39 not receiving any other drugs. After an overnight fast and a basal period of one hour two doses (0.05 and 0.1 U/kg) of 125I labelled soluble human insulin and insulin analogue were injected subcutaneously into the anterior abdominal wall on four separate days. To find a fast acting insulin for meal related requirements in insulin dependent diabetics. MEASUREMENTS and main results--Residual radioactivity at the injection site was measured continuously for the first two hours after injection of the 125I labelled preparations and thereafter for five minutes simultaneously with blood sampling. Frequent venous blood samples were obtained over six hours for determination of plasma immunoreactive insulin, insulin analogue, glucose, and glucagon values. Time to 50% of initial radioactivity at the injection site for the insulin analogue compared with soluble insulin was 61 v 135 minutes (p less than 0.05) with 0.05 U/kg and 67 v 145 minutes (p less than 0.001) with 0.1 U/kg. Concentrations in plasma increased faster after the insulin analogue compared with soluble insulin, resulting in higher plasma concentrations between 10 and 150 minutes (0.001 less than p less than 0.05) after 0.05 U/kg and between 40 and 360 minutes (0.001 less than p less than 0.05) after 0.1 U/kg. The hypoglycaemic response to insulin analogue was a plasma glucose nadir at 60 minutes with both doses compared with 90 and 120 minutes with soluble insulin at 0.5 and 0.1 U/kg respectively. The response of glucagon substantiated the earlier and

  8. Between Analogue and Digital Diagrams

    Directory of Open Access Journals (Sweden)

    Zoltan Bun

    2012-10-01

    Full Text Available This essay is about the interstitial. About how the diagram, as a method of design, has lead fromthe analogue deconstruction of the eighties to the digital processes of the turn of the millennium.Specifically, the main topic of the text is the interpretation and the critique of folding (as a diagramin the beginning of the nineties. It is necessary then to unfold its relationship with immediatelypreceding and following architectural trends, that is to say we have to look both backwards andforwards by about a decade. The question is the context of folding, the exchange of the analogueworld for the digital. To understand the process it is easier to investigate from the fields of artand culture, rather than from the intentionally perplicated1 thoughts of Gilles Deleuze. Both fieldsare relevant here because they can similarly be used as the yardstick against which the era itselfit measured. The cultural scene of the eighties and nineties, including performing arts, movies,literature and philosophy, is a wide milieu of architecture. Architecture responds parallel to itsera; it reacts to it, and changes with it and within it. Architecture is a medium, it has always beena medium, yet the relations are transformed. That’s not to say that technical progress, for exampleusing CAD-software and CNC-s, has led to the digital thinking of certain movements ofarchitecture, (it is at most an indirect tool. But the ‘up-to-dateness’ of the discipline, however,a kind of non-servile reading of an ‘applied culture’ or ‘used philosophy’2 could be the key.(We might recall here, parenthetically, the fortunes of the artistic in contemporary mass society.The proliferation of museums, the magnification of the figure of the artist, the existence of amassive consumption of printed and televised artistic images, the widespread appetite for informationabout the arts, all reflect, of course, an increasingly leisured society, but also relateprecisely to the fact

  9. Management Proposals of the Sabinas Reynosa Aquifer in Northeast Mexico, and Implications in the Development of Main Towns in Chihuahua

    Science.gov (United States)

    Sanchez, E. E.

    2008-12-01

    The Sabinas Reynosa water table aquifer is located in northeast Mexico in the state of Chihuahua, where this hydrologic unit is controlled by Laramide structures. The hydrostratigraphy consists of three units. At the base is a slightly compacted conglomerate HU1. The middle unit HU2 consists of clay materials packed with a carbonate cement. The upper unit is constituted by a sandy caliche with a calcareous matrix with secondary porosity, which allows it to store and transmit large volumes of water. The three units are of Paleogene age. Recently, the towns near the Sabinas Reynosa aquifer have presented supply problems, thus, this project will determine the hydrologic characterization using the groundwater budget method in order to establish the volume of water that the aquifer will yield per unit of time. The first phase consisted of defining the balance equation, by establishing the terms involved in the budget and calculating their respective values. Two different factors were defined: the inflows and outflows. In the first case, underground inflow with 225.68 Mm3 in the last five years, recharge by irrigation with 32.08 Mm3 and anthropogenic recharge with 270.50 Mm3 were considered. In the second case, the factors include underground outflow with 359.55 Mm3, pumping with 561.43 Mm3 and evapotranspiration from the water table with 130.61 Mm3. Although this last variable was calculated on a preliminary basis, a more accurate estimate requires additional studies (in process), with the aim of obtaining a more representative value. In this work is considered that evapotranspiration takes a decisive role in the analysis of the budget and hence, in the decisions that have to be taken for the proper management of the hydrological system.

  10. Effect of the temperature on the sorption of cadmium in natural clinoptilolite from the State of Chihuahua

    International Nuclear Information System (INIS)

    Arambula V, V.

    2004-01-01

    The investigation works related with the removal of cadmium of aqueous solutions, they make emphasis in a great number of materials that were used for this end, as well as in the parameters that influence, such as the temperature and the pH. In this work it was investigated the effect of the temperature on the removal of cadmium, using a zeolitic mineral native of the State of Chihuahua for they were determined it kinetic parameters, those diffusivity coefficients and the retention mechanisms (adsorption or ion exchange) involved. The clinoptilolite samples were characterized by means of scanning electron microscopy in high vacuum (MEB), elementary microanalysis (EDS) and X-ray diffraction (XRD). The experimental part consisted on putting in contact solutions of cadmium with the mineral, varying the temperature, the time of contact or the concentration; the quantification of sodium and cadmium in the liquid phase was carried out by means of atomic absorption spectroscopy (EAA). It was determined the time of equilibrium for the removal process. The temperature and the concentration influence on the process of sorption of cadmium in the zeolitic mineral (kinetics and isotherms). The kinetic model that describes better the sorption process of cadmium in the clinoptilolite was the pseudo-2 order. The apparent coefficient of diffusivity presented a greater value conforms to increment the temperature. The results of the isotherm of adsorption of cadmium presented a better adjustment to the Freundlich model. The quantity of cadmium retained by the mineral it was greater than the quantity of sodium found in the solution after the contact between the solution of cadmium and the zeolitic mineral and in accordance with the obtained separation factors, the natural zeolite shows a greater affinity for the cadmium that for the sodium (α > 1). (Author)

  11. Heavy metals in water of the San Pedro River in Chihuahua, Mexico and its potential health risk

    Directory of Open Access Journals (Sweden)

    Melida Gutierrez

    2008-06-01

    Full Text Available The objective of this study was to determine the seasonal and downstream water quality variations of the San Pedro River in Chihuahua, Mexico. Water samples were collected monthly from October 2005 to August 2006 in triplicate, totaling 165 water samples. The five sampling locations were: below the Francisco I. Madero dam (LP; between Rosales and Delicias (RD; Meoqui (M; El Torreon (ET, and Julimes (LJ. The levels of As, Be, Ca, Cd, Co, Cu, Cr, Fe, Li, Mg, Mn, Mo, Ni, Pb, Sb, Se, Sr, Ti, Ta, V and Zn were measured using an Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES Perkin Elmer 2100. In addition, temperature, pH, electrical conductivity and total and fecal coliformes were determined. The statistical analysis considered a factorial treatment design; where factor A was the location point and factor B was sampling date. In addition, a multivariate technique looking for principal components was performed. The results indicated that some samples exceeded Mexican standards for As, Be, Ca, Cd, Co, Cr, Fe, Mn, Ni, Pb, Sb, Se, Sr and Zn. The As level must be considered for a red flag to the communities along the Rio San Pedro because both the monthly average level (0.10 mg L-1 and location (0.10 mg L-1 exceeded the Mexican and International norms. The multivariate analysis showed a predominant aggregation at the LP location, meaning that there was a predominance of As, Sr, Fe and Li. At the rest of the locations the elements did not present a tendency for aggregation. Statistics applied to sampling month showed that December, January, March and April were aggregated in a negative quadrant of component 1 indicating a predominance of V, Ni, Be, Fe and As. Overall, the results confirmed that this stretch of the San Pedro River is contaminated with heavy metals and other contaminants that might affect human health as well as the health of the ecosystem.

  12. La estructura espacial urbana y accesibilidad diferenciada a centros de empleo en Ciudad Juárez, Chihuahua

    Directory of Open Access Journals (Sweden)

    César M. Fuentes Flores

    2009-01-01

    Full Text Available Existen disparidades intraurbanas en los tiempos de traslado del viaje al trabajo en transporte público y privado, producto de una accesibilidad diferenciada a los centros de empleo en Ciudad Juárez, Chihuahua; el objetivo del artículo es explicarlas. La metodología empleada es el análisis espacial, además se elaboraron cuatro modelos de regresión simple estimados mediante la técnica de mínimos cuadrados ordinarios (MCO. Las variables se construyeron con información de la Encuesta de origen-destino de 1997, el XII Censo general de población y vivienda de 2000 y el XIII Censo económico de 1999, a nivel del área geográfica básica (AGEB. Los resultados de los modelos de regresión indican que el índice de accesibilidad, el balance entre empleos y viviendas, el valor del suelo y las variables aproximadas de uso del suelo (proporción de trabajadores en el sector secundario y terciario muestran efectos estadísticamente significativos al explicar diferencias en los tiempos de traslado al trabajo en transporte público. Así mismo, el índice de accesibilidad, valor del suelo y la proporción de trabajadores en el sector secundario incrementan dichos tiempos en transporte privado. Los resultados tienen implicaciones en términos de políticas de usos del suelo y planeación del transporte.

  13. Gestión de conocimiento en PyME del sector servicios en la ciudad de Chihuahua

    Directory of Open Access Journals (Sweden)

    María del Carmen Gutiérrez-Diez

    2015-01-01

    Full Text Available La gestión de conocimiento es fundamental en la sobrevivencia de las PyME. Este trabajo describe los resultados, obtenidos hasta mayo del 2013, donde en particular se estudian los procesos de gestión de conocimiento, en treinta PyME del sector de servicios, ubicadas en la ciudad de Chihuahua. Se usó como marco de referencia el modelo de espiral de creación de conocimiento organizacional de Nonaka y Takeuchi., a partir del cual de evaluaron las dimensiones de Socialización, Interiorización, Exteriorización y Combinación. Se desarrolló y aplicó un instrumento, dirigido a los empleadores. Los resultados fueron analizados a través de una estadistica descriptiva, correlacional y regresión lineal. En los resultados obtenidos, se describen los valores asignados por los empleadores a estas diferentes categorías. Se obtuvo que las categorías de Socialización y Combinación muestran aportaciones más bajas, mientras que Exteriorización, Interiorización y Combinación aportan más al proceso de gestión de conocimiento. Lo anterior permite concluir una clara falta de estrategias y procesos que favorezcan la generación del conocimiento organizacional para estas PyME, en particular en las actividades de Socialización y Combinación.

  14. Heavy metals in water of the San Pedro River in Chihuahua, Mexico and its potential health risk

    Science.gov (United States)

    Gutiérrez, Roberto L.; Rubio-Arias, Hector; Quintana, Ray; Ortega, Juan Angel; Gutierrez, Melida

    2008-01-01

    The objective of this study was to determine the seasonal and downstream water quality variations of the San Pedro River in Chihuahua, Mexico. Water samples were collected monthly from October 2005 to August 2006 in triplicate, totaling 165 water samples. The five sampling locations were: below the Francisco I. Madero dam (LP); between Rosales and Delicias (RD); Meoqui (M); El Torreon (ET), and Julimes (LJ). The levels of As, Be, Ca, Cd, Co, Cu, Cr, Fe, Li, Mg, Mn, Mo, Ni, Pb, Sb, Se, Sr, Ti, Ta, V and Zn were measured using an Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) Perkin Elmer 2100. In addition, temperature, pH, electrical conductivity and total and fecal coliformes were determined. The statistical analysis considered a factorial treatment design; where factor A was the location point and factor B was sampling date. In addition, a multivariate technique looking for principal components was performed. The results indicated that some samples exceeded Mexican standards for As, Be, Ca, Cd, Co, Cr, Fe, Mn, Ni, Pb, Sb, Se, Sr and Zn. The As level must be considered for a red flag to the communities along the Rio San Pedro because both the monthly average level (0.10 mg L−1) and location (0.10 mg L−1) exceeded the Mexican and International norms. The multivariate analysis showed a predominant aggregation at the LP location, meaning that there was a predominance of As, Sr, Fe and Li. At the rest of the locations the elements did not present a tendency for aggregation. Statistics applied to sampling month showed that December, January, March and April were aggregated in a negative quadrant of component 1 indicating a predominance of V, Ni, Be, Fe and As. Overall, the results confirmed that this stretch of the San Pedro River is contaminated with heavy metals and other contaminants that might affect human health as well as the health of the ecosystem. PMID:18678922

  15. Backbone modified TBA analogues endowed with antiproliferative activity.

    Science.gov (United States)

    Esposito, Veronica; Russo, Annapina; Amato, Teresa; Varra, Michela; Vellecco, Valentina; Bucci, Mariarosaria; Russo, Giulia; Virgilio, Antonella; Galeone, Aldo

    2017-05-01

    The thrombin binding aptamer (TBA) is endowed with antiproliferative properties but its potential development is counteracted by the concomitant anticoagulant activity. Five oligonucleotides (ODNs) based on TBA sequence (GGTTGGTGTGGTTGG) and containing l-residues or both l-residues and inversion of polarity sites have been investigated by NMR and CD techniques for their ability to form G-quadruplex structures. Furthermore, their anticoagulant (PT assay) and antiproliferative properties (MTT assay), and their resistance in fetal bovine serum have been tested. CD and NMR data suggest that the investigated ODNs are able to form right- and left-handed G-quadruplex structures. All ODNs do not retain the anticoagulant activity characteristic of TBA but are endowed with a significant antiproliferative activity against two cancerous cell lines. Their resistance in biological environment after six days is variable, depending on the ODN. A comparison between results and literature data suggests that the antiproliferative activity of the TBA analogues investigated could depends on two factors: a) biological pathways and targets different from those already identified or proposed for other antiproliferative G-quadruplex aptamers, and b) the contribution of the guanine-based degradation products. Modified TBA analogues containing l-residues and inversion of polarity sites lose the anticoagulant activity but gain antiproliferative properties against two cancer cell lines. This article is part of a Special Issue entitled "G-quadruplex" Guest Editor: Dr. Concetta Giancola and Dr. Daniela Montesarchio. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Cyclic cholecystokinin analogues with high selectivity for central receptors

    International Nuclear Information System (INIS)

    Charpentier, B.; Pelaprat, D.; Durieux, C.; Dor, A.; Roques, B.P.; Reibaud, M.; Blanchard, J.C.

    1988-01-01

    Taking as a model the N-terminal folding of the cholecystokinin tyrosine-sulfated octapeptide deduced from conformational studies, two cyclic cholecystokinin (CCK) analogues were synthesized by conventional peptide synthesis. The binding characteristics of these peptides were investigated on brain cortex membranes and pancreatic acini of guinea pig. Compounds I and II were competitive inhibitors of [ 3 H]Boc[Ahx 28,31 ]CCK-(27-33) binding to central CCK receptors and showed a high degree of selectivity for these binding sites. This high selectivity was associated with a high affinity for central CCK receptors. Similar affinities and selectivities were found when 125 I Bolton-Hunter-labeled CCK-8 was used as a ligand. Moreover, these compounds were only weakly active in the stimulation of amylase release from guinea pig pancreatic acini and were unable to induce contractions in the guinea pig ileum. The two cyclic CCK analogues, therefore, appear to be synthetic ligands exhibiting both high affinity and high selectivity for central CCK binding sites. These compounds could help clarify the respective role of central and peripheral receptors for various CCK-8-induced pharmacological effects

  17. Morphostructural characterization of the Charco basin and its surrounding areas in the Chihuahua segment of north Mexican Basin and Range Province

    Science.gov (United States)

    Troiani, Francesco; Menichetti, Marco

    2014-05-01

    The Chihuahua Basin and Range (CBR) is the eastern branch of the northern Mexican Basin and Range Province that, from a morphostructural point of view, presently is one amongst the lesser-known zones of the southern portion of the North America Basin and Range Province. The study area covers an approximately 800 km2-wide portion of the CBR and encompasses the fault-bounded Charco basin and its surrounding areas. The bedrock of the area pertains to the large siliceous-igneous province of the Sierra Madre Occidental and consists of volcanoclastic rocks including Oligocene dacite, rhyolite, rhyolitic tuffs, and polimitic conglomerates. The region is characterized by a series of NW-SE oriented valleys delimited by tilted monoclinal blocks bounded by high angle, SW-dipping, normal faults. Abrupt changes in elevation, alternating between narrow faulted mountain chains and flat arid valleys or basins are the main morphological elements of the area. The valleys correspond to structural grabens filled with Plio-Pleistocene continental sediments. These grabens are about 10 km wide, while the extensional fault system extend over a distance of more than 15 km. The mountain ranges are in most cases continuous over distances that range from 10 to 70 km including different branches of the extensional and transfer faults. The morphogenesis is mainly erosive in character: erosional landforms (such as rocky scarps, ridges, strath-terraces, erosional pediment, reverse slopes, landslide scar zones, litho-structural flat surfaces) dominate the landscape. In contrast, Quaternary depositional landforms are mainly concentrated within the flat valleys or basins. The Quaternary deposits consist of wide alluvial fans extending to the foot of the main ridges, fluvial and debris-slope deposits. The morphostructural characterization of the area integrated different methodologies, including: i) geomorphological and structural field analyses; ii) remote sensing and geo-morphometric investigations

  18. Habitability & Astrobiology Research in Mars Terrestrial Analogues

    Science.gov (United States)

    Foing, Bernard

    2014-05-01

    Journal of Astrobiology , IJA 2011, 10, vol. 3. 137-305 [1] Foing B. et al. (2011) Field astrobiology research at Moon-Mars analogue site: Instruments and methods, IJA 2011, 10 (3), 141;[2] Clarke, J., Stoker, C. Concretions in exhumed & inverted channels near Hanksville Utah: implications for Mars, (IJA 2011, 10 (3), 162;[3] Thiel et al., (2011) PCR-based analysis of microbial communities during the EuroGeoMars campaign at Mars Desert Research Station, Utah. (IJA 2011, 10 (3), 177;[4] Direito et al. (2011). A wide variety of putative extremophiles and large beta-diversity at the Mars Desert Research Station (Utah). (IJA 2011, 10 (3), 191;[5] Orzechowska, G. et al (20110 analysis of Mars Analog soils using solid Phase Microextraction, Organics solvent extraction and GCMS, (IJA 2011, 10 (3), 209; [6] Kotler et al. (2011). Analysis of mineral matrices of planetary soils analogs from the Utah Desert. (IJA 2011, 10 (3), 221; [7] Martins et al. (2011). Extraction of amino acids from soils close to the Mars Desert Research Station (MDRS), Utah. (IJA 2011, 10 (3), 231; [8] Ehrenfreund et al. (2011) Astrobiology and habitability studies in preparation for future Mars missions: trends from investigating minerals, organics and biota. (IJA 2011, 10 (3), 239; [9] Stoker C. et al (2011) Mineralogical, Chemical, Organic & Microbial Properties of Subsurface Soil Cores from Mars Desert Research Station, a Phyllosilicate and Sulfate Rich Mars Analog Site, IJA 2011, 10 (3), 269; [10] Rodrigues L. et al (2014, in preparation) Preventing biocontamination during sterile sampling; [11] Rodrigues L. et al (2014, in preparation) Microbial diversity in MDRS rocks and soils; [12] ILEWG EuroMoonMars Team, (2014, special issue in preparation) Results from ILEWG EuroMoonMars campaign 2013 **Acknowledgements: B.H.Foing (1, 2, 6), C. Stoker (3), P. Ehrenfreund (4, 5), I. Rammos (2), L. Rodrigues (2), A. Svendsen (2), D. Oltheten (2), K. Nebergall (6), M. Battler (6, 7), H. v't Houd (8), A. Bruneau (6

  19. Soft-sediment deformation structures interpreted as seismites in the uppermost Aptian to lowermost Albian transgressive deposits of the Chihuahua basin (Mexico)

    Science.gov (United States)

    Blanc, E.J.-P.; Blanc-Aletru, M. -C.; Mojon, P.-O.

    1998-01-01

    Several levels of soft-sediment deformation structures (s.-s.d.s.) cut by synsedimentary normal faults have been observed in the transition beds between the "Las Vigas" and "La Virgen" formations (Cretaceous) in the northeastern part of the Chihuahua basin in Mexico. These structures consisted of four kinds of motifs (floating breccias, flame-like structures, large pillow structures, and wavy structures). They are restricted to five "stratigraphie" levels (Z1-Z5) and surrounded by undeformed beds in fluvio-lacustrine and tidal deposits and can be traced over a distance of several hundred meters. This deformation is interpreted to have resulted from the combined effects of liquidization and shear stress in soft-sediments due to local earthquakes in the area which could have been generated during the rifting stage of the Chihuahua basin. New constraints placed on the age of the "Las Vigas" Formation (bracketed by Late Aptian charophytes at the bottom and colomiellids of late Aptian to earliest Albian age at the top) suggest that this synrift tectonism lasted at least until the end of the Aptian. ?? Springer-Verlag 1998.

  20. Correlation of the activity of the 238 U in soil and 222 Rn in domiciles, with the rocks of cities of the Estado de Chihuahua

    International Nuclear Information System (INIS)

    Colmenero S, L.; Villalba, L.; Montero C, M.E.

    2004-01-01

    The state of Chihuahua has numerous locations of uranium, being Pena Blanca the great and more important location of the country. Diverse rock types with important quantities of uranium are distributed by the whole state. The igneous extrusive acid rocks are those that have bigger quantity of uranium, like they are the rhyolites and dacites and these rocks are located in enough proportion by the whole state. Some of the main cities of the state are near to locations or uraniferous rocks, as Aldama, Nuevo Casas Grandes, Chihuahua, Jimenez and Bocoyna, other important cities are not near important locations. It was determined specific activity by gamma spectroscopy of the series of the 238 U in soils and determination of the radon concentration in domiciles of the main cities of the state. They were found high specific activity values in soil in eight of the thirteen analyzed cities and important radon concentrations in three cities. It was found relationship among the specific activity in soil in near cities to uraniferous locations. (Author)

  1. Insulin analogues with improved absorption characteristics.

    Science.gov (United States)

    Brange, J; Hansen, J F; Langkjaer, L; Markussen, J; Ribel, U; Sørensen, A R

    1992-01-01

    The insulin preparations available today are not ideal for therapy as s.c. injection does not provide a physiological insulin profile. With the aim to improve the absorption properties recombinant DNA technology has been utilized to design novel insulin molecules with changed physico-chemical characteristics and hence altered subcutaneous absorption kinetics. Soluble, long-acting human insulin analogues in which the isoelectric point has been increased from 5.4 to approx. 7 are absorbed very slowly, providing a more constant basal insulin delivery with lower day-to-day variation than present protracted preparations. In addition they have better storage stability. Rapid-acting human insulin analogues with largely reduced self-association are absorbed substantially faster from subcutaneous tissue than current regular insulin and thus are better suited for bolus injection. The absorption kinetics of these analogues have been able to explain the mechanism behind the dose effect on insulin absorption rate.

  2. Synthesis and anticancer evaluation of spermatinamine analogues

    KAUST Repository

    Moosa, Basem

    2016-02-04

    Spermatinamine was isolated from an Australian marine sponge, Pseudoceratina sp. as an inhibitor of isoprenylcystiene carboxyl methyltransferase (Icmt), an attractive and novel anticancer target. Herein, we report the synthesis of spermatinamine analogues and their cytotoxic evaluation against three human cancer cell lines i.e. cervix adenocarcinoma (HeLa), breast adenocarcinoma (MCF-7), and prostate carcinoma (DU145). Analogues 12, 14 and 15 were found to be the most potent against one or more cell lines with the IC50 values in the range of 5 - 10 μM. The obtained results suggested that longer polyamine linker along with aromatic oxime substitution provided the most potent analogue compounds against cancer cell lines.

  3. Alligator Rivers Analogue Project. Final Report - Volume 1

    Energy Technology Data Exchange (ETDEWEB)

    Duerden, P [Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, NSW (Australia); Lever, D A [AEA Technology, Harwell (United Kingdom); Sverjensky, D A [Johns Hopkins Univ., Baltimore, MD (United States); Townley, L R [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Wembley, WA (Australia). Div. of Water Resources

    1992-07-01

    This summary report, which highlights the work and findings of the Alligator Rivers Analogue Project (ARAP) is one of a series of 16 volumes, listed below. Detailed descriptions and results are provided in Volumes 2 to 16. Full acknowledgment to individual contributions is provided in the individual reports, and in Appendix I of this report. The findings from the technical studies are discussed in the context of assessments of the long-term performance of geological repositories for radioactive wastes, which are being undertaken in many countries. They are also considered in an integrated 'Scenario Development' approach, aimed to understand the formation of the ore deposit. Despite their inherent uncertainties, the findings provide a basis for assessing the way in which radionuclides will migrate in environments with a variety of geologic settings and over a range of different geologic timescales. Thus, section 2 of this report discusses the concept of using uranium deposits as natural analogues and refers to a number of such studies, including those at the Koongarra deposit in the Alligator Rivers Region of the Northern Territory of Australia. Section 3 reviews early scientific work in the Alligator Rivers Region and summarises the results of the analogue studies undertaken between 1981 and 1987 that were funded by the US Nuclear Regulatory Commission (USNRC) and the UK Department of the Environment (UKDoE). Section 4 describes the objectives of ARAP and the manner in which the study was conducted and provides a general outline of the project and a summary of the findings. A general description of the Koongarra ore deposit, the focus of ARAP, is provided in Section 5, with Sections 6-13 providing summaries of the work carried out to characterise the site in detail and provide data for modelling. Sections 14-18 discuss how this data was used in modelling and how the results may be applied for performance assessment studies. Finally, Section 19 considers the

  4. Alligator Rivers Analogue Project. Final Report - Volume 1

    International Nuclear Information System (INIS)

    Duerden, P.; Lever, D.A.; Sverjensky, D.A.; Townley, L.R.

    1992-01-01

    This summary report, which highlights the work and findings of the Alligator Rivers Analogue Project (ARAP) is one of a series of 16 volumes, listed below. Detailed descriptions and results are provided in Volumes 2 to 16. Full acknowledgment to individual contributions is provided in the individual reports, and in Appendix I of this report. The findings from the technical studies are discussed in the context of assessments of the long-term performance of geological repositories for radioactive wastes, which are being undertaken in many countries. They are also considered in an integrated 'Scenario Development' approach, aimed to understand the formation of the ore deposit. Despite their inherent uncertainties, the findings provide a basis for assessing the way in which radionuclides will migrate in environments with a variety of geologic settings and over a range of different geologic timescales. Thus, section 2 of this report discusses the concept of using uranium deposits as natural analogues and refers to a number of such studies, including those at the Koongarra deposit in the Alligator Rivers Region of the Northern Territory of Australia. Section 3 reviews early scientific work in the Alligator Rivers Region and summarises the results of the analogue studies undertaken between 1981 and 1987 that were funded by the US Nuclear Regulatory Commission (USNRC) and the UK Department of the Environment (UKDoE). Section 4 describes the objectives of ARAP and the manner in which the study was conducted and provides a general outline of the project and a summary of the findings. A general description of the Koongarra ore deposit, the focus of ARAP, is provided in Section 5, with Sections 6-13 providing summaries of the work carried out to characterise the site in detail and provide data for modelling. Sections 14-18 discuss how this data was used in modelling and how the results may be applied for performance assessment studies. Finally, Section 19 considers the

  5. Design of insulin analogues for meal-related therapy.

    Science.gov (United States)

    Brange, J

    1993-01-01

    The human insulin in replacement therapy has a hexameric structure. Hexamerization of the insulin molecule facilitates biosynthesis and beta-cell storage of insulin, but is unnecessary for biologic activity and appears to contribute to delayed absorption of exogenous insulin from the subcutis. Insulin analogues with reduced self-association that are produced through recombinant DNA techniques have been shown to have in vivo activity comparable to that of human insulin and absorption kinetics characterized by higher and more constant rates of disappearance from the subcutaneous injection site. In preliminary studies in patients receiving insulin therapy, monomeric insulin analogues have been found to provide glycemic control in the postprandial period that is at least equivalent to that of human insulin. Findings in these studies suggest that the use of such analogues may provide meal-related insulin effects closer to those observed in the physiologic state by limiting excessive postprandial glucose excursions and decreasing the risk of late hypoglycemia. Banting and Best revolutionized diabetes therapy 70 years ago with the extraction of insulin from animal pancreas glands (J Lab Clin Med 7:464-472, 1922). Since that time, many refinements of the therapeutic properties of pharmaceutical preparations of the hormone have been introduced. Until recently, however, such advances have been limited to improvements in insulin purity, insulin species, and adjustment of the composition of the vehicle with respect to auxiliary substances and other additives. With the advent of recombinant DNA techniques, it has become possible to optimize the insulin molecule itself for purposes of replacement therapy.(ABSTRACT TRUNCATED AT 250 WORDS)

  6. Pharmacological characterisation of strychnine and brucine analogues at glycine and alpha7 nicotinic acetylcholine receptors

    DEFF Research Database (Denmark)

    Jensen, Anders A.; Gharagozloo, Parviz; Birdsall, Nigel J M

    2006-01-01

    of tertiary and quaternary analogues as well as bisquaternary dimers of strychnine and brucine at human alpha1 and alpha1beta glycine receptors and at a chimera consisting of the amino-terminal domain of the alpha7 nicotinic receptor (containing the orthosteric ligand binding site) and the ion channel domain...... of strychnine and brucine, none of the analogues displayed significant selectivity between the alpha1 and alpha1beta subtypes. The structure-activity relationships for the compounds at the alpha7/5-HT3 chimera were significantly different from those at the glycine receptors. Most strikingly, quaternization...... of strychnine and brucine with substituents possessing different steric and electronic properties completely eliminated the activity at the glycine receptors, whereas binding affinity to the alpha7/5-HT3 chimera was retained for the majority of the quaternary analogues. This study provides an insight...

  7. Analogue alternative the electronic analogue computer in Britain and the USA, 1930-1975

    CERN Document Server

    Small, James S

    2013-01-01

    We are in the midst of a digital revolution - until recently, the majority of appliances used in everyday life have been developed with analogue technology. Now, either at home or out and about, we are surrounded by digital technology such as digital 'film', audio systems, computers and telephones. From the late 1940s until the 1970s, analogue technology was a genuine alternative to digital, and the two competing technologies ran parallel with each other. During this period, a community of engineers, scientists, academics and businessmen continued to develop and promote the analogue computer.

  8. Leaching Behavior of Slags from AN Old Lead Smelter in Chihuahua, Mexico: Metals, Chlorides, Nitrates, Sulfates and Tds Analyses

    Science.gov (United States)

    Espejel-Garcia, D.; Wenglas-Lara, G.; Villalobos-Aragon, A.; Espejel-Garcia, V. V.

    2013-05-01

    Waste materials (such as, smelter slags, waste glass, tires, plastics, rubbish, ashes, etc.), have a large potential to substitute natural materials, reducing costs, especially for the construction industry. Smelter slags are resistant and have better compression strength values in comparison to natural aggregates, and generally are far beyond of what the standard ratios need to qualify a material as a good one for construction. But this material has a big problem within it: the existence of toxic elements and compounds in high concentrations, which means that water and soil contamination can be present after water infiltrates through this material; so we perform leaching experiments to characterize and measure the possible contamination under controlled conditions. To perform the slags-leaching experiments, we used an EA-NEN-7375-2004 tank test standard from Netherlands. This test was selected because to our knowledge it is the only one which allows the use of coarse material, as the one utilized in construction. The leaching experiments sampling was performed at different times: 6, 24, 168 and 360 hours, to compare the leachate concentration at the two different pH's values (5 and 8) selected to simulate real conditions. For the leaching experiments, the slags were mixed with natural road base material (gravel-sands from volcanic rocks) at different proportions of 30% and 50%. In order to understand the slags' leaching behavior, other experiments were carried out with the pure material, for both (slags and natural aggregates). After analyses by ICP-OES , the slags from this smelter in Chihuahua contain Pb (0.5 - 4 wt.%), Zn (15-35 wt.%) and As (0.6 wt.%), as well such as: bicarbonates, chlorides, nitrates, sulfates, Mg, K, Na, Ca and TDS. Based on the results of the leaching analyses, via atomic absorption technique, we conclude that Pb and As concentrations are provided by the slags, meanwhile, the bicarbonates, chlorides, Na and Ca are contributed by the road

  9. Prussian Blue Analogues of Reduced Dimensionality

    NARCIS (Netherlands)

    Gengler, Regis Y. N.; Toma, Luminita M.; Pardo, Emilio; Lloret, Francesc; Ke, Xiaoxing; Van Tendeloo, Gustaaf; Gournis, Dimitrios; Rudolf, Petra

    2012-01-01

    Mixed-valence polycyanides (Prussian Blue analogues) possess a rich palette of properties spanning from room-temperature ferromagnetism to zero thermal expansion, which can be tuned by chemical modifications or the application of external stimuli (temperature, pressure, light irradiation). While

  10. Somatostatin analogue scintigraphy and tuberculosis: case report

    International Nuclear Information System (INIS)

    Biancheri, I.; Rudenko, B.; Vautrin, P.; Raddoul, J.; Lamfichek, N.; Kantelip, B.; Mantion, G.

    2005-01-01

    Scintigraphy using a radiolabelled somatostatin analogue (111 In-pentetreotide) is useful in the detection of neuroendocrine tumors. But this radiopharmaceutical accumulates also in solid tumours or in inflammatory diseases such as granulomatosis. We present a case of 111 In-pentetreotide uptake in a tuberculous adenopathy. (author)

  11. Analogue computer display of accelerator beam optics

    International Nuclear Information System (INIS)

    Brand, K.

    1984-01-01

    Analogue computers have been used years ago by several authors for the design of magnetic beam handling systems. At Bochum a small analogue/hybrid computer was combined with a particular analogue expansion and logic control unit for beam transport work. This apparatus was very successful in the design and setup of the beam handling system of the tandem accelerator. The center of the stripper canal was the object point for the calculations, instead of the high energy acceleration tube a drift length was inserted into the program neglecting the weak focusing action of the tube. In the course of the installation of a second injector for heavy ions it became necessary to do better calculations. A simple method was found to represent accelerating sections on the computer and a particular way to simulate thin lenses was adopted. The analogue computer system proved its usefulness in the design and in studies of the characteristics of different accelerator installations over many years. The results of the calculations are in very good agreement with real accelerator data. The apparatus is the ideal tool to demonstrate beam optics to students and accelerator operators since the effect of a change of any of the parameters is immediately visible on the oscilloscope

  12. Scintigraphy with labelled analogues of the somatostatin

    International Nuclear Information System (INIS)

    Duet, M.; Ajzenberg, C.; Warnet, A.; Mundler, O.

    1998-01-01

    The receptors of the somatostatin have been localized in a big number of tumors, whom a great number are neuro-endocrine tumors. However, some tumors that have not this differentiation (breast cancer, lymphomas, cerebral tumors) possess them as well. Analogues of somatostatin, labelled with isotopes having a gamma emission, allow from now their detection in vivo. (N.C.)

  13. Ultrasound exfoliation of inorganic analogues of graphene

    Czech Academy of Sciences Publication Activity Database

    Štengl, Václav; Henych, Jiří; Slušná, Michaela; Ecorchard, Petra

    2014-01-01

    Roč. 9, APR (2014), s. 1-14 ISSN 1556-276X R&D Projects: GA ČR(CZ) GA14-05146S Institutional support: RVO:61388980 Keywords : Ultrasound * Exfoliation * Graphene inorganic analogues Subject RIV: CA - Inorganic Chemistry Impact factor: 2.779, year: 2014

  14. MARSI: metabolite analogues for rational strain improvement

    DEFF Research Database (Denmark)

    Cardoso, João G. R.; Zeidan, Ahmad A; Jensen, Kristian

    2018-01-01

    reactions in an organism can be used to predict effects of MAs on cellular phenotypes. Here, we present the Metabolite Analogues for Rational Strain Improvement (MARSI) framework. MARSI provides a rational approach to strain improvement by searching for metabolites as targets instead of genes or reactions...

  15. Natural analogues of bitumen and bituminized radioactive waste

    International Nuclear Information System (INIS)

    Hellmuth, K.-H.

    1989-07-01

    Occurrences of natural bitumen provide possibilities to identify and assess materials, processes, phenomena and conditions in nature which can serve as model cases valid also with respect to a final repository. Natural bitumens meet the basic requirements for use as natural analogues. In natural sites, processes of bitumen formation and degradation often work simultaneously. The major processes are thermal alteration, evaporation, reaction with water, biodegradation, oxidation, weathering and radiation degradation. Progress in analytical organic geochemistry made during recent years has enabled a deeper understanding of the structural and compositional effects of these processes on bitumen. This is necessary in natural analogue applications. The time scales involved in degradation processes, as observed in natural occurrences, exceed the time scales dictated by the half-lives of most important fission products in low and medium level waste by orders of magnitude. Only exposure to the weather at the surface leads to a more rapid destruction of bitumen. Trace metals in bitumen arenot released until the matrix is completely destroyed. Products of radiation degradation and weathering of bitumen are able, to a certain degree, to delay migration of the metal ions released. Impregnation with bitumen may effectively reduce the microbial decomposition of easily destructable organic waste components, as can be deduced on the basis of the excellent preservation of fossils observed in bitumen. The complexity of all the natural sites described requires extensive understanding of the origin and kind of organic material in bitumen, its maturation, migration, alteration and degradation and of the geological and tectonic evolution of the site. The latter is used for establishing the time scale

  16. A novel lunar bed rest analogue.

    Science.gov (United States)

    Cavanagh, Peter R; Rice, Andrea J; Licata, Angelo A; Kuklis, Matthew M; Novotny, Sara C; Genc, Kerim O; Englehaupt, Ricki K; Hanson, Andrea M

    2013-11-01

    Humans will eventually return to the Moon and thus there is a need for a ground-based analogue to enable the study of physiological adaptations to lunar gravity. An important unanswered question is whether or not living on the lunar surface will provide adequate loading of the musculoskeletal system to prevent or attenuate the bone loss that is seen in microgravity. Previous simulations have involved tilting subjects to an approximately 9.5 degrees angle to achieve a lunar gravity component parallel to the long-axis of the body. However, subjects in these earlier simulations were not weight-bearing, and thus these protocols did not provide an analogue for load on the musculoskeletal system. We present a novel analogue which includes the capability to simulate standing and sitting in a lunar loading environment. A bed oriented at a 9.5 degrees angle was mounted on six linear bearings and was free to travel with one degree of freedom along rails. This allowed approximately 1/6 body weight loading of the feet during standing. "Lunar" sitting was also successfully simulated. A feasibility study demonstrated that the analogue was tolerated by subjects for 6 d of continuous bed rest and that the reaction forces at the feet during periods of standing were a reasonable simulation of lunar standing. During the 6 d, mean change in the volume of the quadriceps muscles was -1.6% +/- 1.7%. The proposed analogue would appear to be an acceptable simulation of lunar gravity and deserves further exploration in studies of longer duration.

  17. Cephalostatin analogues--synthesis and biological activity.

    Science.gov (United States)

    Flessner, Timo; Jautelat, Rolf; Scholz, Ulrich; Winterfeldt, Ekkehard

    2004-01-01

    Starting off in the early 90's the field of cephalostatin analogues has continually expanded over the last 10 years. First syntheses prepared symmetric analogues like 14b (119) and 26 (65), which were subsequently desymmetrized to provide analogues like beta-hydroxy ketone 31 (19). Importantly the straightforward approach provided already compounds with mu-molar potency and the same pattern of activity as cephalostatin 1 (1) (see Chapter 2.1). Chemically more demanding, two new methods for the directed synthesis of (bissteroidal) pyrazines were devised and subsequently applied to a wide variety of differently functionalized coupling partners. These new methods allowed for the synthesis of various analogues (Chapter 2.2.; and, last but not least, for the totals synthesis of several cephalostatin natural products; Chapter 1.). Functionalization and derivatization of the 12-position was performed (Chapter 2.1 and 3) and synthetic approaches to establish the D-ring double bond were successfully investigated (Chapter 3). [figure: see text] Dealing synthetically with the spiroketal moiety, novel oxidative opening procedures on monomeric delta 14, 15-steroids were devised as well as intensive studies regarding spiroketal synthesis and spiroketal rearrangements were conducted (Chapter 3.2. and 4.). Last but not least direct chemical modification of ritterazines and cephalostatins were studied, which provided a limited number of ritterazine analogues (Chapter 4.). All these synthetic activities towards analogues are summarized in Fig. 18. During this period of time the growing number of cephalostatins and ritterazines on the one hand and of analogues on the other hand provided several SAR trends, which can guide future analogue synthesis. The combined SAR findings are displayed in Fig. 19. So far it is apparent that: Additional methoxylations or hydroxylations in the steroidal A ring core structure (1-position) are slightly decreasing activity (compare cephalostatin 1 1 to

  18. Thorium deposit of Morro do Ferro in Pocos de Caldas, Brazil: an analogue of a radioactive waste repository

    International Nuclear Information System (INIS)

    Franca, E.P.; Carlos, M.T.; Sachett, I.A.; Campos, M.J.M.T. de; Lei, W.; Eisenbud, M.; New York Univ., NY

    1986-01-01

    A highly weathered deposit of thorium and rare earth elements located near the summit of a hill (Morro do Ferro) in Pocos de Caldas M.G., is being studied as an analogue for a radioactive waste repository that, sometime in the distant future, may be eroded to the surface or intruded by groundwater. Th - serves as an analogue for Pu 4+ and La 3+ as an analogue for Cm 3+ and Am 3+ . The mobilization rates of the analogue elements by groundwater are so slow (10 -7 to 10 -9 per year), as to suggest that essentially complete radioactive decay of transuranic actinides would occur in place, even under the unfavorable conditions that exist at a site such as this. (Author) [pt

  19. U-Series Disequilibria in Soils, Pena Blanca Natural Analog, Chihuahua, Mexico

    International Nuclear Information System (INIS)

    D. French; E. Anthony; P. Goodell

    2006-01-01

    The Nopal I uranium deposit located in the Sierra Pena Blanca, Mexico. The deposit was mined in the early 1980s, and ore was stockpiled close by. This stockpile area was cleared and is now referred to as the Prior High Grade Stockpile (PHGS). Some of the high-grade boulders from the site rolled downhill when it was cleared in the 1990s. For this study soil samples were collected from the alluvium surrounding and underlying one of these boulders. A bulk sample of the boulder was also collected. Because the Prior High Grade Stockpile had no ore prior to the 1980s a maximum residence time for the boulder is about 25 years, this also means that the soil was at background as well. The purpose of this study is to characterize the transport of uranium series radionuclides from ore to the soil. Transport is characterized by determining the activities of individual radionuclides and daughter to parent ratios. Isotopes of the uranium series decay chain detected include 210 Pb, 234 U, 230 Th, 226 Ra, 214 Pb, and 214 Bi. Peak areas for each isotope are determined using gamma-ray spectroscopy with a Canberra Ge (Li) detector and GENIE 2000 software. The boulder sample is close to secular equilibrium when compared to the standard BL-5 (Beaver Lodge Uraninite from Canada). Results for the soils, however, indicate that some daughter/parent pairs are in secular disequilibrium. These daughter/parent (D/P) ratios include 230 Th/ 234 U, which is greater than unity, 226 Ra/ 230 Th, which is also greater than unity, and 210 Pb/ 214 Bi, which is less than unity. The gamma-ray spectrum for organic material lacks 230 Th peaks, but contains 234 U and 226 Ra, indicating that plants preferentially incorporate 226 Ra. Our results, combined with previous studies require multistage history of mobilization of the uranium series radionuclides. Earlier studies at the ore zone could limit the time span for mobilization only to a few thousand years. The contribution of this study is that the short

  20. U-Sries Disequilibra in Soils, Pena Blanca Natural Analog, Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    D. French; E. Anthony; P. Goodell

    2006-03-16

    The Nopal I uranium deposit located in the Sierra Pena Blanca, Mexico. The deposit was mined in the early 1980s, and ore was stockpiled close by. This stockpile area was cleared and is now referred to as the Prior High Grade Stockpile (PHGS). Some of the high-grade boulders from the site rolled downhill when it was cleared in the 1990s. For this study soil samples were collected from the alluvium surrounding and underlying one of these boulders. A bulk sample of the boulder was also collected. Because the Prior High Grade Stockpile had no ore prior to the 1980s a maximum residence time for the boulder is about 25 years, this also means that the soil was at background as well. The purpose of this study is to characterize the transport of uranium series radionuclides from ore to the soil. Transport is characterized by determining the activities of individual radionuclides and daughter to parent ratios. Isotopes of the uranium series decay chain detected include {sup 210}Pb, {sup 234}U, {sup 230}Th, {sup 226}Ra, {sup 214}Pb, and {sup 214}Bi. Peak areas for each isotope are determined using gamma-ray spectroscopy with a Canberra Ge (Li) detector and GENIE 2000 software. The boulder sample is close to secular equilibrium when compared to the standard BL-5 (Beaver Lodge Uraninite from Canada). Results for the soils, however, indicate that some daughter/parent pairs are in secular disequilibrium. These daughter/parent (D/P) ratios include {sup 230}Th/{sup 234}U, which is greater than unity, {sup 226}Ra/{sup 230}Th, which is also greater than unity, and {sup 210}Pb/{sup 214}Bi, which is less than unity. The gamma-ray spectrum for organic material lacks {sup 230}Th peaks, but contains {sup 234}U and {sup 226}Ra, indicating that plants preferentially incorporate {sup 226}Ra. Our results, combined with previous studies require multistage history of mobilization of the uranium series radionuclides. Earlier studies at the ore zone could limit the time span for mobilization only

  1. Exploration of charge states of balanol analogues acting as ATP-competitive inhibitors in kinases.

    Science.gov (United States)

    Hardianto, Ari; Yusuf, Muhammad; Liu, Fei; Ranganathan, Shoba

    2017-12-28

    (-)-Balanol is an ATP mimic that inhibits protein kinase C (PKC) isozymes and cAMP-dependent protein kinase (PKA) with limited selectivity. While PKA is a tumour promoter, PKC isozymes act as tumour promoters or suppressors, depending on the cancer type. In particular, PKCε is frequently implicated in cancer promotion, making it a potential target for anticancer drugs. To improve isozyme selectivity of balanol, exhaustive structural and activity relationship (SAR) studies have been performed in the last two decades, but with limited success. More recently, fluorination on balanol has shown improved selectivity for PKCε, although the fluorine effect is not yet clearly understood. Understanding the origin to this fluorine-based selectivity will be valuable for designing better balanol-based ATP mimicking inhibitors. Computational approaches such as molecular dynamics (MD) simulations can decipher the fluorine effect, provided that correct charges have been assigned to a ligand. Balanol analogues have multiple ionisable functional groups and the effect of fluorine substitutions on the exact charge state of each analogue bound to PKA and to PKCε needs to be thoroughly investigated in order to design highly selective inhibitors for therapeutic applications. We explored the charge states of novel fluorinated balanol analogues using MD simulations. For different potential charge states of these analogues, Molecular Mechanics Generalized Born Surface Area (MMGBSA) binding energy values were computed. This study suggests that balanol and the most potent fluorinated analogue (5S fluorine substitution on the azepane ring), have charges on the azepane ring (N1), and the phenolic (C6''OH) and the carboxylate (C15''O 2 H) groups on the benzophenone moiety, when bound to PKCε as well as PKA. To the best our knowledge, this is the first study showing that the phenolate group is charged in balanol and its analogues binding to the ATP site of PKCε. Correct charge

  2. Synthesis and Biological Evaluation of 7-Deoxy-Epothilone Analogues

    Directory of Open Access Journals (Sweden)

    Laura M. Woods

    2017-03-01

    Full Text Available The synthesis of two deoxygenated analogues of potent epothilones is reported in an effort to analyze the relative importance of molecular conformation and ligand–target interactions to biological activity. 7-deoxy-epothilone D and 7-deoxy-(S-14-methoxy-epothilone D were prepared through total synthesis and shown to maintain the conformational preferences of their biologically active parent congeners through computer modeling and nuclear magnetic resonance (NMR studies. The significant decrease in observed potency for each compound suggests that a hydrogen bond between the C7-hydroxyl group and the tubulin binding site plays a critical role in the energetics of binding in the epothilone class of polyketides.

  3. Un acercamiento al concepto de representación: el caso de las mujeres políticas en el estado de Chihuahua

    Directory of Open Access Journals (Sweden)

    Martha Estela Pérez

    2013-01-01

    Full Text Available En este documento se reflexiona sobre el fenómeno de la representación simbólica y política de las mujeres en el estado de Chihuahua. Este caso se centra en la escasa representación del sexo femenino en la política institucional y, de igual forma, se hace un acercamiento a los esquemas culturales que siguen vigentes en la esfera pública, los cuales no sólo inciden en el quehacer político femenino y masculino, sino que también conllevan a generar espacios de discriminación e inequidad y obstaculizan el empoderamiento femenino.

  4. Medición de la vulnerabilidad: el caso de la adicción a drogas ilícitas en Chihuahua, México

    Directory of Open Access Journals (Sweden)

    Roberto J. Córdova-Contreras

    2010-01-01

    Full Text Available En el presente estudio se explora el modelo de Rogers para cuantificar la vulnerabilidad, pero sin pruebas empíricas de su utilidad. Éste usa un triángulo equilátero cuyos lados representan los recursos personales y el apoyo ambiental, y la base el grado de vulnerabilidad. Se comparan los datos de la Encuesta estatal de adicciones del estado de Chihuahua, del año 2000, con los resultados obtenidos con la visión tradicional de la epidemiología. El enfoque de la vulnerabilidad identificó a la población analizada como muy sensible. La comparación entre los métodos mostró diferencias importantes, pero no permiten inferir cuál es mejor. Estudios futuros podrán examinar la utilidad del modelo abordado aquí, en diversos contextos.

  5. SITUACIÓN ECONÓMICA DE LA PRODUCCIÓN DE BOVINOS DE CARNE EN EL ESTADO DE CHIHUAHUA, MÉXICO

    Directory of Open Access Journals (Sweden)

    Nicol\\u00E1s Callejas-Ju\\u00E1rez

    2014-01-01

    Full Text Available El objetivo del presente estudio fue analizar la situación microeconómica de Unidades Representativas de Producción (URP del sistema de producción vaca-becerro en el estado de Chihuahua, Mé - xico. Se analizaron cuatro escalas de producción (20, 40, 200 y 500 vientres en edad productiva en cuatro regiones del es - tado de Chihuahua, México. Con la metodología de panel se obtuvieron costos e ingresos en 2009, con la participación de cinco a diez productores por panel. Se utiliz ó el modelo de simulación económica MEXSIM de la Universidad de Texas A&M, adaptado para México por la Red Nacional de Inves - tigación en Política Pública. La viabilidad económica medi - da a través de la probabilidad de obtener reservas finales de efectivo negativas y perder capital, fue buena para CHBC20, CHBC200 y CHBC500 y moderada para CHBC40. La uti - lidad neta más baja por vientre fue para CHBC40 ($ 27,76 dólares y la más alta para CHBC20 ($ 403,42 dólares. La relación beneficio-costo fue de 2,16 y 1,78 para CHBC500 y CHBC200, respectivamente. Todas las URP obtuvieron el ingreso neto suficiente para cubrir sus gastos familiares, ex - cepto CHBC20 que generó 70%. Las URP con mayor escala fueron más rentables que las pequeñas y todas trabajaron so - bre su punto de equilibrio. El margen de ganancia fue mayor cuanto más grande fue la escala de producción, con lo que se mostró evidencia de economía de escala.

  6. Analysis of single nucleotide polymorphisms in the 3' region of the estrogen receptor 1 gene in normal and cryptorchid Miniature Dachshunds and Chihuahuas.

    Science.gov (United States)

    Pathirana, Indunil Nishantha; Tanaka, Kakeru; Kawate, Noritoshi; Tsuji, Makoto; Kida, Kayoko; Hatoya, Shingo; Inaba, Toshio; Tamada, Hiromichi

    2010-08-01

    This study was performed to examine the distribution of single nucleotide polymorphisms (SNPs) and estimated haplotypes in the canine estrogen receptor (ER) alpha gene (ESR1) and the association of them with different phenotypes of cryptorchidism (CO) in Miniature Dachshunds and Chihuahuas. Forty CO and 68 normal dogs were used, and CO was classified into unilateral (UCO; n=33) and bilateral CO (BCO; n=5) or into abdominal (ACO; n=16) and inguinal CO (ICO; n=22). Thirteen DNA fragments located in the 70-kb region at the 3' end of ESR1 were amplified by PCR and sequenced to examine 13 SNPs (#1-#13) reported in a canine SNP database. Ten SNPs (#1-#4, #7, #8, #10-#13) were not polymorphic, and 5 new SNPs (#14-#18) were discovered. A common haplotype block in normal, CO and CO phenotypes was identified for an approximately 20-kb region encompassing 4 SNPs (#14-#17). Allele, genotype and haplotype frequencies in CO without classification by phenotype and also in UCO, ACO and ICO phenotypes were not statistically different from the normal group. Significant differences in genotype frequencies and homozygosity for the estimated GTTG haplotype within the block were observed in BCO compared with the normal group, although the number of BCO animals was small. Our results demonstrate that the examined SNPs and haplotypes in the 3' end of canine ESR1 are not associated with unilateral, abdominal and inguinal CO phenotypes and CO per se in Miniature Dachshunds and Chihuahuas. Further studies are necessary to suggest a clear association between the ESR1 SNPs and bilateral CO in dogs.

  7. La vegetación como sistema de control para las Islas de Calor Urbano en Ciudad Juárez, Chihuahua

    Directory of Open Access Journals (Sweden)

    Maria Goretti Salas Esparza

    2017-06-01

    Full Text Available A nivel mundial, el territorio ha experimentado un proceso de urbanización, el cual ha modificado las condiciones físicas y climatológicas como consecuencia de la densificación y construcción de las zonas urbanas, sobre todo a partir de la utilización de materiales que retienen el calor y que propician el fenómeno de isla de calor urbano (ICU, término establecido por Gordon Manley en 1958 (Fernández, 1996. Este trabajo evalúa el impacto que tienen las áreas verdes para actuar como sistema de control de isla de calor sobre Ciudad Juárez, Chihuahua, durante el verano del 2016. La metodología consistió en analizar cuatro áreas verdes para determinar la diferencia de temperatura que existe entre las zonas arboladas y las no arboladas, registrando temperaturas con sensores Hobo®, cada 15 minutos. Los resultados obtenidos demostraron que existe una diferencia de temperatura de 3,82 °C entre los lugares arbolados y no arbolados en el área verde con mayor nivel de vegetación, mientras que el área verde con menor nivel de vegetación se encontró una diferencia de 0,53 °C. Sin embargo, el impacto que tendrán sobre la zona urbana dependerá de la configuración y características de la misma área verde.   Documeto fianciado bajo el marco Tesis de Maestría en Planificación y Desarrollo Urbano " Áreas verdes como sistema de control para las Islas de Calor Urbano en Ciudad Juárez, Chihuahua".Universidad Autónoma de Ciudad Juárez

  8. Boron hydride analogues of the fullerenes

    International Nuclear Information System (INIS)

    Quong, A.A.; Pederson, M.R.; Broughton, J.Q.

    1994-01-01

    The BH moiety is isoelectronic with C. We have studied the stability of the (BH) 60 analogue of the C 60 fullerene as well as the dual-structure (BH) 32 icosahedron, both of them being putative structures, by performing local-density-functional electronic calculations. To aid in our analysis, we have also studied other homologues of these systems. We find that the latter, i.e., the dual structure, is the more stable although the former is as stable as one of the latter's lower homologues. Boron hydrides, it seems, naturally form the dual structures used in algorithmic optimization of complex fullerene systems. Fully relaxed geometries are reported as well as electron affinities and effective Hubbard U parameters. These systems form very stable anions and we conclude that a search for BH analogues of the C 60 alkali-metal supeconductors might prove very fruitful

  9. Lead optimization of antimalarial propafenone analogues.

    Science.gov (United States)

    Lowes, David; Pradhan, Anupam; Iyer, Lalitha V; Parman, Toufan; Gow, Jason; Zhu, Fangyi; Furimsky, Anna; Lemoff, Andrew; Guiguemde, W Armand; Sigal, Martina; Clark, Julie A; Wilson, Emily; Tang, Liang; Connelly, Michele C; Derisi, Joseph L; Kyle, Dennis E; Mirsalis, Jon; Guy, R Kiplin

    2012-07-12

    Previously reported studies identified analogues of propafenone that had potent antimalarial activity, reduced cardiac ion channel activity, and properties that suggested the potential for clinical development for malaria. Careful examination of the bioavailability, pharmacokinetics, toxicology, and efficacy of this series of compounds using rodent models revealed orally bioavailable compounds that are nontoxic and suppress parasitemia in vivo. Although these compounds possess potential for further preclinical development, they also carry some significant challenges.

  10. The Brookhaven electron analogue, 1953--1957

    Energy Technology Data Exchange (ETDEWEB)

    Plotkin, M.

    1991-12-18

    The following topics are discussed on the Brookhaven electron analogue: L.J. Haworth and E.L. VanHorn letters; Original G.K. Green outline for report; General description; Parameter list; Mechanical Assembly; Alignment; Degaussing; Vacuum System; Injection System; The pulsed inflector; RF System; Ferrite Cavity; Pick-up electrodes and preamplifiers; Radio Frequency power amplifier; Lens supply; Controls and Power; and RF acceleration summary.

  11. Electromagnetic wave analogue of electronic diode

    OpenAIRE

    Shadrivov, Ilya V.; Powell, David A.; Kivshar, Yuri S.; Fedotov, Vassili A.; Zheludev, Nikolay I.

    2010-01-01

    An electronic diode is a nonlinear semiconductor circuit component that allows conduction of electrical current in one direction only. A component with similar functionality for electromagnetic waves, an electromagnetic isolator, is based on the Faraday effect of the polarization state rotation and is also a key component of optical and microwave systems. Here we demonstrate a chiral electromagnetic diode, which is a direct analogue of an electronic diode: its functionality is underpinned by ...

  12. The Brookhaven electron analogue, 1953--1957

    International Nuclear Information System (INIS)

    Plotkin, M.

    1991-01-01

    The following topics are discussed on the Brookhaven electron analogue: L.J. Haworth and E.L. VanHorn letters; Original G.K. Green outline for report; General description; Parameter list; Mechanical Assembly; Alignment; Degaussing; Vacuum System; Injection System; The pulsed inflector; RF System; Ferrite Cavity; Pick-up electrodes and preamplifiers; Radio Frequency power amplifier; Lens supply; Controls and Power; and RF acceleration summary

  13. Correlation of the activity of the {sup 238} U in soil and {sup 222} Rn in domiciles, with the rocks of cities of the Estado de Chihuahua; Correlacion de la actividad del {sup 238} U en suelo y {sup 222} Rn en domicilios, con las rocas de ciudades del Estado de Chihuahua

    Energy Technology Data Exchange (ETDEWEB)

    Colmenero S, L.; Villalba, L.; Montero C, M.E. [Centro de Investigacion en Materiales Avanzados (CIMAV), Av. Miguel de Cervantes 120 C.P. 31109 Chihuahua (Mexico)]. e-mail: luis.colmenero@cimav.edu.mx

    2004-07-01

    The state of Chihuahua has numerous locations of uranium, being Pena Blanca the great and more important location of the country. Diverse rock types with important quantities of uranium are distributed by the whole state. The igneous extrusive acid rocks are those that have bigger quantity of uranium, like they are the rhyolites and dacites and these rocks are located in enough proportion by the whole state. Some of the main cities of the state are near to locations or uraniferous rocks, as Aldama, Nuevo Casas Grandes, Chihuahua, Jimenez and Bocoyna, other important cities are not near important locations. It was determined specific activity by gamma spectroscopy of the series of the {sup 238} U in soils and determination of the radon concentration in domiciles of the main cities of the state. They were found high specific activity values in soil in eight of the thirteen analyzed cities and important radon concentrations in three cities. It was found relationship among the specific activity in soil in near cities to uraniferous locations. (Author)

  14. The Palmottu natural analogue project. Progress report 1996. The behaviour of natural radionuclides in and around uranium deposits, Nr. 10

    International Nuclear Information System (INIS)

    Lampinen, P.; Ruskeeniemi, T.; Blomqvist, R.

    1997-01-01

    The report summarises the activities carried out in the Palmottu Natural Analogue project in 1996. Efforts has mainly been directed toward the hydrogeological and hydrogeochemical studies of the site. Other activities in 1996 have included up-dating the structural model of the site and radionuclide migration studies. The topical summaries documented are: (1) Hydrogeological studies, (2) Up-dating the structural model of the site, (3) Hydrogeochemical studies at Palmottu, and (4) Radionuclide migration studies. (41 refs.)

  15. Four Generations of Transition State Analogues for Human Purine Nucleoside Phosphorylase

    Energy Technology Data Exchange (ETDEWEB)

    Ho, M.; Shi, W; Rinaldo-Mathis, A; Tyler, P; Evans, G; Almo, S; Schramm, V

    2010-01-01

    Inhibition of human purine nucleoside phosphorylase (PNP) stops growth of activated T-cells and the formation of 6-oxypurine bases, making it a target for leukemia, autoimmune disorders, and gout. Four generations of ribocation transition-state mimics bound to PNP are structurally characterized. Immucillin-H (K*{sub i} = 58 pM, first-generation) contains an iminoribitol cation with four asymmetric carbons. DADMe-Immucillin-H (K*{sub i} = 9 pM, second-generation), uses a methylene-bridged dihydroxypyrrolidine cation with two asymmetric centers. DATMe-Immucillin-H (K*{sub i} = 9 pM, third-generation) contains an open-chain amino alcohol cation with two asymmetric carbons. SerMe-ImmH (K*{sub i} = 5 pM, fourth-generation) uses achiral dihydroxyaminoalcohol seramide as the ribocation mimic. Crystal structures of PNPs establish features of tight binding to be; (1) ion-pair formation between bound phosphate (or its mimic) and inhibitor cation, (2) leaving-group interactions to N1, O6, and N7 of 9-deazahypoxanthine, (3) interaction between phosphate and inhibitor hydroxyl groups, and (4) His257 interacting with the 5{prime}-hydroxyl group. The first generation analogue is an imperfect fit to the catalytic site with a long ion pair distance between the iminoribitol and bound phosphate and weaker interactions to the leaving group. Increasing the ribocation to leaving-group distance in the second- to fourth-generation analogues provides powerful binding interactions and a facile synthetic route to powerful inhibitors. Despite chemical diversity in the four generations of transition-state analogues, the catalytic site geometry is almost the same for all analogues. Multiple solutions in transition-state analogue design are available to convert the energy of catalytic rate enhancement to binding energy in human PNP.

  16. Analogue to Digital and Digital to Analogue Converters (ADCs and DACs): A Review Update

    CERN Document Server

    Pickering, J.

    2015-06-15

    This is a review paper updated from that presented for CAS 2004. Essentially, since then, commercial components have continued to extend their performance boundaries but the basic building blocks and the techniques for choosing the best device and implementing it in a design have not changed. Analogue to digital and digital to analogue converters are crucial components in the continued drive to replace analogue circuitry with more controllable and less costly digital processing. This paper discusses the technologies available to perform in the likely measurement and control applications that arise within accelerators. It covers much of the terminology and 'specmanship' together with an application-oriented analysis of the realisable performance of the various types. Finally, some hints and warnings on system integration problems are given.

  17. Natural analogue synthesis report, TDR-NBS-GS-000027 REV00 ICN02

    International Nuclear Information System (INIS)

    Simmons, A.; Nieder-Westermann, G.; Stuckless, J.; Dobson, P.; Unger, A.J.A.; Kwicklis, E.; Lichtner, P.; Carey, B.; Wolde, G.; Murrel, M.; Kneafsey, T.J.; Meijer, A.; Faybishenko, B.

    2002-01-01

    The purpose of this report is to present analogue studies and literature reviews designed to provide qualitative and quantitative information to test and provide added confidence in process models abstracted for performance assessment (PA) and model predictions pertinent to PA. This report provides updates to studies presented in the Yucca Mountain Site Description (CRWMS M and O 2000 [151945], Section 13) and new examples gleaned from the literature, along with results of quantitative studies conducted specifically for the Yucca Mountain Site Characterization Project (YMP). The intent of the natural analogue studies was to collect corroborative evidence from analogues to demonstrate additional understanding of processes expected to occur during postclosure at a potential Yucca Mountain repository. The report focuses on key processes by providing observations and analyses of natural and anthropogenic (human-induced) systems to improve understanding and confidence in the operation of these processes under conditions similar to those that could occur in a nuclear waste repository. The process models include those that represent both engineered and natural barrier processes. A second purpose of this report is to document the various applications of natural analogues to geologic repository programs, focusing primarily on the way analogues have been used by the YMP. This report is limited to providing support for PA in a confirmatory manner and to providing corroborative inputs for process modeling activities. Section 1.7 discusses additional limitations of this report. Key topics for this report are analogues to emplacement drift degradation, waste form degradation, waste package degradation, degradation of other materials proposed for the engineered barrier, seepage into drifts, radionuclide flow and transport in the unsaturated zone (UZ), analogues to coupled thermal-hydrologic-mechanical-chemical processes, saturated zone (SZ) transport, impact of radionuclide

  18. Natural analogue synthesis report, TDR-NBS-GS-000027 rev00 icn02

    Energy Technology Data Exchange (ETDEWEB)

    Simmons, A.; Nieder-Westermann, G.; Stuckless, J.; Dobson, P.; Unger, A.J.A.; Kwicklis, E.; Lichtner, P.; Carey, B.; Wolde, G.; Murrel,M.; Kneafsey, T.J.; Meijer, A.; Faybishenko, B.

    2002-04-01

    The purpose of this report is to present analogue studies and literature reviews designed to provide qualitative and quantitative information to test and provide added confidence in process models abstracted for performance assessment (PA) and model predictions pertinent to PA. This report provides updates to studies presented in the Yucca Mountain Site Description (CRWMS M&O 2000 [151945], Section 13) and new examples gleaned from the literature, along with results of quantitative studies conducted specifically for the Yucca Mountain Site Characterization Project (YMP). The intent of the natural analogue studies was to collect corroborative evidence from analogues to demonstrate additional understanding of processes expected to occur during postclosure at a potential Yucca Mountain repository. The report focuses on key processes by providing observations and analyses of natural and anthropogenic (human-induced) systems to improve understanding and confidence in the operation of these processes under conditions similar to those that could occur in a nuclear waste repository. The process models include those that represent both engineered and natural barrier processes. A second purpose of this report is to document the various applications of natural analogues to geologic repository programs, focusing primarily on the way analogues have been used by the YMP. This report is limited to providing support for PA in a confirmatory manner and to providing corroborative inputs for process modeling activities. Section 1.7 discusses additional limitations of this report. Key topics for this report are analogues to emplacement drift degradation, waste form degradation, waste package degradation, degradation of other materials proposed for the engineered barrier, seepage into drifts, radionuclide flow and transport in the unsaturated zone (UZ), analogues to coupled thermal-hydrologic-mechanical-chemical processes, saturated zone (SZ) transport, impact of radionuclide release

  19. Design of Thymidine Analogues Targeting Thymidilate Kinase of Mycobacterium tuberculosis

    Directory of Open Access Journals (Sweden)

    Luc Calvin Owono Owono

    2013-01-01

    Full Text Available We design here new nanomolar antituberculotics, inhibitors of Mycobacterium tuberculosis thymidine monophosphate kinase (TMPKmt, by means of structure-based molecular design. 3D models of TMPKmt-inhibitor complexes have been prepared from the crystal structure of TMPKmt cocrystallized with the natural substrate deoxythymidine monophosphate (dTMP (1GSI for a training set of 15 thymidine analogues (TMDs with known activity to prepare a QSAR model of interaction establishing a correlation between the free energy of complexation and the biological activity. Subsequent validation of the predictability of the model has been performed with a 3D QSAR pharmacophore generation. The structural information derived from the model served to design new subnanomolar thymidine analogues. From molecular modeling investigations, the agreement between free energy of complexation (ΔΔGcom and Ki values explains 94% of the TMPKmt inhibition (pKi=-0.2924ΔΔGcom+3.234;R2=0.94 by variation of the computed ΔΔGcom and 92% for the pharmacophore (PH4 model (pKi=1.0206×pKipred-0.0832,  R2=0.92. The analysis of contributions from active site residues suggested substitution at the 5-position of pyrimidine ring and various groups at the 5′-position of the ribose. The best inhibitor reached a predicted Ki of 0.155 nM. The computational approach through the combined use of molecular modeling and PH4 pharmacophore is helpful in targeted drug design, providing valuable information for the synthesis and prediction of activity of novel antituberculotic agents.

  20. Breast cancer imaging using radiolabelled somatostatin analogues

    International Nuclear Information System (INIS)

    Dalm, Simone U.; Melis, Marleen; Emmering, Jasper; Kwekkeboom, Dik J.; Jong, Marion de

    2016-01-01

    Imaging and therapy using radiolabelled somatostatin analogues are methods successfully used in patients with somatostatin receptor (SSTR)-expressing neuroendocrine tumours. Since these techniques were first introduced, many improvements have been made. SSTR expression has also been reported on breast cancer (BC). Currently mammography, magnetic resonance imaging and ultrasound are the most frequent methods used for BC imaging. Since SSTR expression on BC was demonstrated, clinical studies examining the feasibility of visualizing primary BC using SSTR radioligands have been performed. However, to date SSTR-mediated nuclear imaging is not used clinically in BC patients. The aim of this review is to assess whether recent improvements made within nuclear medicine may enable SSTR-mediated imaging to play a role in BC management. For this we critically analysed results of past studies and discussed the potential of the improvements made within nuclear medicine on SSTR-mediated nuclear imaging of BC. Seven databases were searched for publications on BC imaging with SSTR radioligands. The papers found were analysed by 3 individual observers to identify whether the studies met the pre-set inclusion criteria defined as studies in which nuclear imaging using radiolabelled SST analogues was performed in patients with breast lesions. Twenty-four papers were selected for this review including studies on SSTR-mediated nuclear imaging in BC, neuroendocrine BC and other breast lesions. The analysed studies were heterogeneous with respect to the imaging method, imaging protocol, patient groups and the radiolabelled SST analogues used. Despite the fact that the analysed studies were heterogeneous, sensitivity for primary BC ranged from 36–100%. In a subset of the studies LN lesions were visualized, but sensitivity was lower compared to that for primary tumours. A part of the studies included benign lesions and specificity ranged from 22–100%. Furthermore, false negatives and

  1. Long term corrosion of iron at the water logged site Nydam in Denmark

    DEFF Research Database (Denmark)

    Matthiesen, Henning; Hilbert, Lisbeth Rischel; Gregory, David

    2005-01-01

    Long term corrosion of iron at the water logged site Nydam in Denmark; studies of enviroment, archaeological artefacts, and modern analogues, Prediction of long term corrosion behaviour in nuclear waste systems.......Long term corrosion of iron at the water logged site Nydam in Denmark; studies of enviroment, archaeological artefacts, and modern analogues, Prediction of long term corrosion behaviour in nuclear waste systems....

  2. The Lehmer Matrix and Its Recursive Analogue

    Science.gov (United States)

    2010-01-01

    LU factorization of matrix A by considering det A = det U = ∏n i=1 2i−1 i2 . The nth Catalan number is given in terms of binomial coefficients by Cn...for failing to comply with a collection of information if it does not display a currently valid OMB control number . 1. REPORT DATE 2010 2. REPORT...TYPE 3. DATES COVERED 00-00-2010 to 00-00-2010 4. TITLE AND SUBTITLE The Lehmer matrix and its recursive analogue 5a. CONTRACT NUMBER 5b

  3. Nuclear waste geochemistry: natural and anthropic analogues

    International Nuclear Information System (INIS)

    Petit, J.C.

    1997-01-01

    The geochemical evolution of nuclear waste storage is difficult to describe, due to the long time scales involved, the radioactivity confinement complexity and the un-natural radionuclides which evolution is not known. In order to carry out a long term prediction, a special approach is used, based on a combination of experiments conducted in laboratories and in situ, modelizations and comparisons with process and material analogues (natural or man-made, such as basaltic and rhyolitic volcanic glasses, plutonium, historical and archaeological artefacts)

  4. Electronic analogue simulator of radio cardiograms

    International Nuclear Information System (INIS)

    Roux, G.; Lansiart, A.; Vernejoul, P. de; Kellershohn, C.

    1967-01-01

    The various parameters of the heart pump and of the blood circulation can be determined by radio-cardio-graphical techniques. The curves thus obtained can be more easily used in radiocardiography if the electronic analogue simulator described here is employed. The experimental and simulated radio-cardiograms are made to coincide by varying the electrical parameters of the simulator. Using simple charts it is possible to obtain directly the actual original physiological parameters from these electrical parameters. Some examples are given showing the excellent accuracy obtained in the determination of ejection indices by the simulator. (authors) [fr

  5. Natural Analogues of CO2 Geological Storage

    International Nuclear Information System (INIS)

    Perez del Villar, L.; Pelayo, M.; Recreo, F.

    2007-01-01

    Geological storage of carbon dioxide is nowadays, internationally considered as the most effective method for greenhouse gas emission mitigation, in order to minimize the global climate change universally accepted. Nevertheless, the possible risks derived of this long-term storage have a direct influence on its public acceptance. Among the favourable geological formations to store CO2, depleted oil and gas fields, deep saline reservoirs, and unamiable coal seams are highlighted. One of the most important objectives of the R and D projects related to the CO2 geological storage is the evaluation of the CO2 leakage rate through the above mentioned geological formations. Therefore, it is absolutely necessary to increase our knowledge on the interaction among CO2, storage and sealing formations, as well as on the flow paths and the physical resistance of the sealing formation. The quantification of the CO2 leakage rate is essential to evaluate the effects on the human and animal health, as well as for the ecosystem and water quality. To achieve these objectives, the study of the natural analogues is very useful in order to know the natural leakage rate to the atmosphere, its flow paths, the physical, chemical and mineralogical modifications due to the long term interaction processes among the CO2 and the storage and sealing formations, as well as the effects on the groundwaters and ecosystems. In this report, we have tried to summarise the main characteristics of the natural reservoirs and surficial sources of CO2, which are both natural analogues of the geological storage and CO2 leakage, studied in EEUU, Europe and Australia. The main objective of this summary is to find the possible applications for long-term risk prediction and for the performance assessment by means of conceptual and numerical modelling, which will allow to validate the predictive models of the CO2 storage behaviour, to design and develop suitable monitoring techniques to control the CO2 behaviour

  6. Digital and analogue industrial radiography, application fields

    International Nuclear Information System (INIS)

    Willems, Peter; Millord, Erik Yardin

    2000-01-01

    Full text: Reusable phosphor screens for computer radiography (CR), amorphous selenium screens for direct radiography (DR), film digitalisation (FD) constitute imaging methods accepted by industry and are used for non-destructive radiographic testing (RT). Economic pressures are involving and affecting digital RT technology. Standards and codes for film radiography and radioscopy qualification do no longer cover the wide range of digital RT applications. It will be our task to optimise the performance of digital RT characterisation and to create appropriate examination methods to use all these new and existent technologies. In the meantime, an increasing automation and control of manual methods of analogue radiography can as well be expected. (author)

  7. Activities of Native and Tyrosine-69 Mutant Phospholipases A2 on Phospholipid Analogues. A Reevaluation of the Minimal Substrate Requirements

    NARCIS (Netherlands)

    Kuipers, Oscar P.; Dekker, Nicolaas; Verheij, Hubertus M.; Haas, Gerard H. de

    1990-01-01

    The role of Tyr-69 of porcine pancreatic phospholipase A2 in substrate binding was studied with the help of proteins modified by site-directed mutagenesis and phospholipid analogues with a changed head-group geometry. Two mutants were used containing Phe and Lys, respectively, at position 69.

  8. U.S. Nuclear Regulatory Commission natural analogue research program

    International Nuclear Information System (INIS)

    Kovach, L.A.; Ott, W.R.

    1995-01-01

    This article describes the natural analogue research program of the U.S. Nuclear Regulatory Commission (US NRC). It contains information on the regulatory context and organizational structure of the high-level radioactive waste research program plan. It also includes information on the conditions and processes constraining selection of natural analogues, describes initiatives of the US NRC, and describes the role of analogues in the licensing process

  9. Conformationally restrained aromatic analogues of fosmidomycin and FR900098.

    Science.gov (United States)

    Kurz, Thomas; Schlüter, Katrin; Pein, Miriam; Behrendt, Christoph; Bergmann, Bärbel; Walter, Rolf D

    2007-07-01

    The synthesis and in-vitro antimalarial activity of conformationally restrained bis(pivaloyloxymethyl) ester analogues of the natural product fosmidomycin is presented. In contrast to alpha-aryl-substituted analogues, conformationally restrained aromatic analogues exhibit only moderate in-vitro antimalarial activity against the chloroquine-sensitive strain 3D7 of Plasmodium falciparum. The most active derivative displays an IC(50) value of 47 microM.

  10. Andrographolide and analogues in cancer prevention.

    Science.gov (United States)

    Mishra, Siddhartha Kumar; Tripathi, Swati; Shukla, Archana; Oh, Seung Hyun; Kim, Hwan Mook

    2015-01-01

    Andrographis paniculata is a medicinal plant traditionally used for treatment of cough and cold, fever, laryngitis, and several infectious diseases. Extracts of A. paniculata have shown versatile potency against various diseases including cancer. The active biomolecules of A. paniculata mainly are lactone and diterpene. Andrographolide and analogues have been widely used for prevention of different diseases. Andrographolides have shown potent antiinflammatory and anticancer activities. It showed potentials as chemopreventive agents by suppressing growth of cancer cells by inhibiting NF-kappaB, PI3K/AKT and other kinase pathways and by inducing apoptosis. Andrographolide induced both intrinsic and extrinsic apoptosis pathway in different cancer cells via expression of different anti-apoptotic protein like Bax, p53, and activated caspases. Andrographolide was successfully used as an antineoplastic drug in cancer chemotherapy. Andrographolide inhibited the growth of human breast, prostate, and hepatoma tumors. Andrographolide and analogues need to be subjected to further clinical and biomedical studies in cancer chemoprevention. Andrographolide could be potent anticancer agent when used in combination with other chemotherapeutic agents.

  11. Statistical analogues of thermodynamic extremum principles

    Science.gov (United States)

    Ramshaw, John D.

    2018-05-01

    As shown by Jaynes, the canonical and grand canonical probability distributions of equilibrium statistical mechanics can be simply derived from the principle of maximum entropy, in which the statistical entropy S=- {k}{{B}}{\\sum }i{p}i{log}{p}i is maximised subject to constraints on the mean values of the energy E and/or number of particles N in a system of fixed volume V. The Lagrange multipliers associated with those constraints are then found to be simply related to the temperature T and chemical potential μ. Here we show that the constrained maximisation of S is equivalent to, and can therefore be replaced by, the essentially unconstrained minimisation of the obvious statistical analogues of the Helmholtz free energy F = E ‑ TS and the grand potential J = F ‑ μN. Those minimisations are more easily performed than the maximisation of S because they formally eliminate the constraints on the mean values of E and N and their associated Lagrange multipliers. This procedure significantly simplifies the derivation of the canonical and grand canonical probability distributions, and shows that the well known extremum principles for the various thermodynamic potentials possess natural statistical analogues which are equivalent to the constrained maximisation of S.

  12. Studies of natural analogues and geological systems. Their importance to performance assessment

    International Nuclear Information System (INIS)

    Brandberg, F.; Grundfelt, B.; Hoeglund, L.O.; Skagius, K.; Karlsson, Fred; Smellie, J.

    1992-04-01

    This review has involved studies of natural analogues and natural geological systems leading to the identification and quantification of processes and features of importance to the performance and safety of repositories for radioactive waste. The features and processes selected for the study comprise general geochemical issues related to the performance of the near- and of the far-field, the performance and durability of construction materials and the effects of glaciation. For each of these areas a number of potentially important processes for repository performance have been described, and evidence for their existence, as well as quantification of parameters of models describing the processes, have been sought from major natural analogue studies and site investigations. The review has aimed at covering a relatively broad range of issues at the expense of in-depth analysis. The quantitative data presented are in most cases compilations of data from the literature; in a few cases results of evaluations made within the current project are included. The results of the study show that studies of natural analogues and natural geological systems have provided significant information regarding many issues of importance to repository performance. In several cases the evidence from natural analogues has demonstrated that processes assumed to take place in repositories actually occur in natural systems or under conditions similar to those predicted to prevail in a future repository. One example of such a process is coprecipitation of fission products and ferric oxyhydroxides as an analogue to corrosion products from a steel canister. In addition, the study of concentration gradients of uranium and other trace substances in the rock surrounding groundwater conduits confirm that matrix diffusion occurs in nature and that the diffusivities in the rock matrix measured in the laboratory are consistent with the observations in nature

  13. Maqarin natural analogue project: Phase IV. Reconnaissance mission report (April 28 to May 7, 1999)

    Energy Technology Data Exchange (ETDEWEB)

    Smellie, J.A.T. [ed.] [Conterra AB, Uppsala (Sweden)

    2000-08-01

    Final planning of the Technical Proposal for Phase IV of the Maqarin Natural Analogue Project was preceded by a ten day Reconnaissance Mission to the Jordan sites. The main objective of this mission was to: i) allow new organisations within the project to become familiar with the geological context of the Maqarin and Central Jordan sites and also to appreciate the prevailing technical and logistical limitations, ii) carry out limited field investigations, and iii) based on the experience from these two points, provide the opportunity to finalise the Maqarin Phase IV Technical Proposal. This report details the results of the mission.

  14. Maqarin natural analogue project: Phase IV. Reconnaissance mission report (April 28 to May 7, 1999)

    International Nuclear Information System (INIS)

    Smellie, J.A.T.

    2000-08-01

    Final planning of the Technical Proposal for Phase IV of the Maqarin Natural Analogue Project was preceded by a ten day Reconnaissance Mission to the Jordan sites. The main objective of this mission was to: i) allow new organisations within the project to become familiar with the geological context of the Maqarin and Central Jordan sites and also to appreciate the prevailing technical and logistical limitations, ii) carry out limited field investigations, and iii) based on the experience from these two points, provide the opportunity to finalise the Maqarin Phase IV Technical Proposal. This report details the results of the mission

  15. Protolytic properties of polyamine wasp toxin analogues studied by 13C NMR spectroscopy

    DEFF Research Database (Denmark)

    Strømgaard, Kristian; Piazzi, Lorna; Olsen, Christian A

    2006-01-01

    Acid-base properties of the natural polyamine wasp toxin PhTX-433 (1) and seven synthetic analogues [PhTX-343 (2), PhTX-334 (3), PhTX-443 (4), PhTX-434 (5), PhTX-344 (6), PhTX-444 (7), and PhTX-333 (8)], each having four protolytic sites, were characterized by 13C NMR spectroscopy. Nonlinear......, multiparameter, simultaneous fit of all chemical shift data obtained from the NMR titration curves yielded macroscopic pKa values as well as intrinsic chemical shift data of all differently protonated macrospecies. Analyses of the chemical shift data demonstrated strong interactions between all four sites...

  16. Space Analogue Environments: Are the Populations Comparable?

    Science.gov (United States)

    Sandal, G. M.

    Background: Much of our present understanding about psychology in space is based on studies of groups operating in so-called analogue environments where personnel are exposed to many of the same stressors as those experienced by astronauts in space. One possible problem with extrapolating results is that personnel operating in various hazardous and confined environments might differ in characteristics influencing coping, interaction, and performance. The object of this study was to compare the psychological similarity of these populations in order to get a better understanding of whether this extrapolation is justifiable. The samples investigated include polar crossings (N= 22), personnel on Antarctic research stations (N= 183), several military occupations (N= 187), and participants in space simulation studies (N=20). Methods: Personnel in each of these environments were assessed using the Personality Characteristic Inventory (PCI) and Utrecht Coping List (UCL). The PCI is a multidimensional trait assessment battery that measures various aspects of achievement orientation and social competence. The UCL is a questionnaire designed to assess habitual coping strategies when encountering stressful or demanding situations. Results: Only minor differences in use of habitual coping strategies were evident across the different samples. In relation to personality scores, the military subjects and participants in space simulation studies indicated higher competitiveness and negative instrumentality compared to both the personnel on Antarctic research stations and participants in polar expedition. Among the personnel on Antarctic research stations, significant gender differences were found with women scoring lower on competitiveness, negative instrumentality and impatience/irritability. Compared to the other samples, the participants in polar expeditions were found to be more homogeneous in personality and no significant gender differences were evident on the traits that

  17. Glaciation and geosphere evolution - Greenland Analogue Project

    International Nuclear Information System (INIS)

    Hirschorn, S.; Vorauer, A.; Belfadhel, M.B.; Jensen, M.

    2011-01-01

    The deep geological repository concept for the long-term management of used nuclear fuel involves the containment and isolation of used nuclear fuel in a suitable geological formation. A key objective of the Canadian Nuclear Waste Management Organization (NWMO) geoscience technical research program is to advance the understanding of geosphere stability and its resilience to perturbations over time frames of relevance to a deep geological repository. Glaciation has been identified as the most probable and intense perturbation relevant to a deep geological repository associated with long-term climate change in northern latitudes. Given that the North American continent has been re-glaciated nine times over the past million years, it is strongly expected that a deep geological repository within a suitable crystalline or sedimentary rock formation in Canada will be subject to glaciation events associated with long-term climate change. As such, NWMO's geoscience research program has placed particular emphasis on investigations of the response of the geosphere to glaciations. As surface conditions change from present day conditions to periglacial, followed by ice-sheet cover of variable thickness and rapid glacial retreat, transient geochemical, hydraulic, mechanical and temperature conditions will be simultaneously imposed on groundwater systems. NWMO research activities related to glaciation events and their impacts on groundwater system evolution are being undertaken using a multi-disciplinary approach aimed at collecting multiple lines of evidence. These investigations include assessment of the: Impact of an ice sheet on groundwater composition at repository depth using the Greenland Ice Sheet as an analogue to future glaciations in North America; Expected physical and temporal surface boundary conditions related to potential future glaciation events by estimating the magnitude and time rate of change of ice sheet thickness, ground surface temperature and

  18. Structural, Biochemical, and Computational Studies Reveal the Mechanism of Selective Aldehyde Dehydrogenase 1A1 Inhibition by Cytotoxic Duocarmycin Analogues.

    Science.gov (United States)

    Koch, Maximilian F; Harteis, Sabrina; Blank, Iris D; Pestel, Galina; Tietze, Lutz F; Ochsenfeld, Christian; Schneider, Sabine; Sieber, Stephan A

    2015-11-09

    Analogues of the natural product duocarmycin bearing an indole moiety were shown to bind aldehyde dehydrogenase 1A1 (ALDH1A1) in addition to DNA, while derivatives without the indole solely addressed the ALDH1A1 protein. The molecular mechanism of selective ALDH1A1 inhibition by duocarmycin analogues was unraveled through cocrystallization, mutational studies, and molecular dynamics simulations. The structure of the complex shows the compound embedded in a hydrophobic pocket, where it is stabilized by several crucial π-stacking and van der Waals interactions. This binding mode positions the cyclopropyl electrophile for nucleophilic attack by the noncatalytic residue Cys302, thereby resulting in covalent attachment, steric occlusion of the active site, and inhibition of catalysis. The selectivity of duocarmycin analogues for ALDH1A1 is unique, since only minor alterations in the sequence of closely related protein isoforms restrict compound accessibility. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Analogues of Cucurbita maxima trypsin inhibitor III (CMTI-III) with elastase inhibitory activity.

    Science.gov (United States)

    Rózycki, J; Kupryszewski, G; Rolka, K; Ragnarsson, U; Zbyryt, T; Krokoszyńska, I; Wilusz, T

    1994-04-01

    Three new CMTI-III analogues containing the Val residue in the reactive site (position 5) were synthesized by the solid-phase method. The analogues displayed an elastase inhibitory activity. It is shown that the removal of the N-terminal Arg residue and the introduction of the Gly-Pro-Gln tripeptide in the region 23-25 decreases the antielastase activity by two orders of magnitude. The removal of the disulfide bridge in positions 16-28 and the substitution of Ala for Cys16 and Gly for Cys28 decreases the activity (measured as Ka with HLE) by five orders of magnitude as compared with [Val5]CMTI-III.

  20. UK Natural Analogue Co-Ordinating Group: first annual progress report

    International Nuclear Information System (INIS)

    Hooker, P.J.; Chapman, N.A.

    1987-11-01

    The British Geological Survey is reponsible for co-ordinating the Department of the Environment's programme of natural analogue studies of radionuclide migration, a research programme that involved both UK and overseas sites. Co-ordination is achieved through the UK Natural Analogue Co-ordinating Group (NACG) which was established in October 1986. It has met three times to date and its function is to ensure that the different research projects have an integrated purpose aimed at improving and applying our understanding of natural geochemical processes in a way that will increase our confidence in long-term modelling predictions. Improved modelling prediction of radionuclide transport in the geosphere will directly benefit the performance and safety assessments of proposed radioactive waste repositories. (author)

  1. Electromagnetic wave analogue of an electronic diode

    International Nuclear Information System (INIS)

    Shadrivov, Ilya V; Powell, David A; Kivshar, Yuri S; Fedotov, Vassili A; Zheludev, Nikolay I

    2011-01-01

    An electronic diode is a nonlinear semiconductor circuit component that allows conduction of electrical current in one direction only. A component with similar functionality for electromagnetic waves, an electromagnetic isolator, is based on the Faraday effect of rotation of the polarization state and is also a key component in optical and microwave systems. Here we demonstrate a chiral electromagnetic diode, which is a direct analogue of an electronic diode: its functionality is underpinned by an extraordinarily strong nonlinear wave propagation effect in the same way as the electronic diode function is provided by the nonlinear current characteristic of a semiconductor junction. The effect exploited in this new electromagnetic diode is an intensity-dependent polarization change in an artificial chiral metamolecule. This microwave effect exceeds a similar optical effect previously observed in natural crystals by more than 12 orders of magnitude and a direction-dependent transmission that differs by a factor of 65.

  2. Reflective analogue optical link operating issues

    CERN Document Server

    Batten, Jeremy

    1996-01-01

    The proposed readout of analogue data from CMS tracker will use an optical fibre link. The choice of transmitter/receiver technology, however, has been the subject of intense research and development by the RD23 collaboration. One solution uses passive devices, multi-quantum well modulators, at the detector front end, and continuous wave driving lasers at the readout back end. This system has been tested at Imperial College. We report on the following: problems of noise associated with multimoded behaviour of a degraded laser; measurements of laser wavelength dependence on both drive current and temperature; and modulator reflectance dependence on laser wavelength. We extrapolate the findings to system issues, highlighting the degree of temperature control required of the driving laser.

  3. The gravitational analogue of the Witten effect

    International Nuclear Information System (INIS)

    Foda, O.

    1984-06-01

    In the presence of massive fermions, and assuming a non-vanishing theta-parameter as the only source of CP-violation, the Witten effect [a shift in the electric charge of a magnetic monopole due to CP-non-conservation] is shown to follow from an anomalous chiral commutator. Next, given the gravitational contribution to the chiral anomaly, the corresponding anomalous commutator for Dirac fermion currents in a gravitational background is derived. From that, we infer the equivalence of a theta R-tilde R term in the Lagrangian to a shift in the mass parameter of the NUT metric, in proportion to theta. This is interpreted as the gravitational analogue of the Witten effect. Its relevance to certain Kaluza-Klein monopoles is briefly discussed. (author)

  4. Gravitational analogue of the Witten effect

    Energy Technology Data Exchange (ETDEWEB)

    Foda, O. (International Centre for Theoretical Physics, Trieste (Italy))

    1985-07-22

    In the presence of massive fermions, and assuming a non-vanishing theta-parameter as the only source of CP violation, the Witten effect (a shift in the electric charge of a magnetic monopole due to CP non-conservation) is shown to follow from an anomalous chiral commutator. Next, given the gravitational contribution to the chiral anomaly, the corresponding anomalous commutator for Dirac fermion currents in a gravitational background is derived. From that, we infer the equivalence of a thetaR tildeR term in the lagrangian to a shift in the mass parameter of the NUT metric, in proportion to theta. This is interpreted as the gravitational analogue of the Witten effect. Its relevance to certain Kaluza-Klein monopoles is briefly discussed.

  5. The gravitational analogue of the Witten effect

    International Nuclear Information System (INIS)

    Foda, O.

    1985-01-01

    In the presence of massive fermions, and assuming a non-vanishing theta-parameter as the only source of CP violation, the Witten effect (a shift in the electric charge of a magnetic monopole due to CP non-conservation) is shown to follow from an anomalous chiral commutator. Next, given the gravitational contribution to the chiral anomaly, the corresponding anomalous commutator for Dirac fermion currents in a gravitational background is derived. From that, we infer the equivalence of a thetaR tildeR term in the lagrangian to a shift in the mass parameter of the NUT metric, in proportion to theta. This is interpreted as the gravitational analogue of the Witten effect. Its relevance to certain Kaluza-Klein monopoles is briefly discussed. (orig.)

  6. Solution Processed PEDOT Analogues in Electrochemical Supercapacitors.

    Science.gov (United States)

    Österholm, Anna M; Ponder, James F; Kerszulis, Justin A; Reynolds, John R

    2016-06-01

    We have designed fully soluble ProDOTx-EDOTy copolymers that are electrochemically equivalent to electropolymerized PEDOT without using any surfactants or dispersants. We show that these copolymers can be incorporated as active layers in solution processed thin film supercapacitors to demonstrate capacitance, stability, and voltage similar to the values of those that use electrodeposited PEDOT as the active material with the added advantage of the possibility for large scale, high-throughput processing. These Type I supercapacitors provide exceptional cell voltages (up to 1.6 V), highly symmetrical charge/discharge behavior, promising long-term stability exceeding 50 000 charge/discharge cycles, as well as energy (4-18 Wh/kg) and power densities (0.8-3.3 kW/kg) that are comparable to those of electrochemically synthesized analogues.

  7. Synthesis of an Orthogonal Topological Analogue of Helicene

    DEFF Research Database (Denmark)

    Wixe, Torbjörn; Wallentin, Carl‐Johan; Johnson, Magnus T.

    2013-01-01

    The synthesis of an orthogonal topological pentamer analogue of helicene is presented. This analogue forms a tubular structure with its aromatic systems directed parallel to the axis of propagation, which creates a cavity with the potential to function as a host molecule. The synthetic strategy r...

  8. Insulin analogues and severe hypoglycaemia in type 1 diabetes

    DEFF Research Database (Denmark)

    Kristensen, P L; Hansen, L S; Jespersen, M J

    2012-01-01

    The effect of insulin analogues on glycaemic control is well-documented, whereas the effect on avoidance of severe hypoglycaemia remains tentative. We studied the frequency of severe hypoglycaemia in unselected patients with type 1 diabetes treated with insulin analogues, human insulin, or mixed...

  9. Magnetic properties of Proxima Centauri b analogues

    Science.gov (United States)

    Zuluaga, Jorge I.; Bustamante, Sebastian

    2018-03-01

    The discovery of a planet around the closest star to our Sun, Proxima Centauri, represents a quantum leap in the testability of exoplanetary models. Unlike any other discovered exoplanet, models of Proxima b could be contrasted against near future telescopic observations and far future in-situ measurements. In this paper we aim at predicting the planetary radius and the magnetic properties (dynamo lifetime and magnetic dipole moment) of Proxima b analogues (solid planets with masses of ∼ 1 - 3M⊕ , rotation periods of several days and habitable conditions). For this purpose we build a grid of planetary models with a wide range of compositions and masses. For each point in the grid we run the planetary evolution model developed in Zuluaga et al. (2013). Our model assumes small orbital eccentricity, negligible tidal heating and earth-like radiogenic mantle elements abundances. We devise a statistical methodology to estimate the posterior distribution of the desired planetary properties assuming simple lprior distributions for the orbital inclination and bulk composition. Our model predicts that Proxima b would have a mass 1.3 ≤Mp ≤ 2.3M⊕ and a radius Rp =1.4-0.2+0.3R⊕ . In our simulations, most Proxima b analogues develop intrinsic dynamos that last for ≥4 Gyr (the estimated age of the host star). If alive, the dynamo of Proxima b have a dipole moment ℳdip >0.32÷2.9×2.3ℳdip , ⊕ . These results are not restricted to Proxima b but they also apply to earth-like planets having similar observed properties.

  10. Natural analogues of nuclear waste glass corrosion

    International Nuclear Information System (INIS)

    Abrajano, T.A. Jr.; Ebert, W.L.; Luo, J.S.

    1999-01-01

    This report reviews and summarizes studies performed to characterize the products and processes involved in the corrosion of natural glasses. Studies are also reviewed and evaluated on how well the corrosion of natural glasses in natural environments serves as an analogue for the corrosion of high-level radioactive waste glasses in an engineered geologic disposal system. A wide range of natural and experimental corrosion studies has been performed on three major groups of natural glasses: tektite, obsidian, and basalt. Studies of the corrosion of natural glass attempt to characterize both the nature of alteration products and the reaction kinetics. Information available on natural glass was then compared to corresponding information on the corrosion of nuclear waste glasses, specifically to resolve two key questions: (1) whether one or more natural glasses behave similarly to nuclear waste glasses in laboratory tests, and (2) how these similarities can be used to support projections of the long-term corrosion of nuclear waste glasses. The corrosion behavior of basaltic glasses was most similar to that of nuclear waste glasses, but the corrosion of tektite and obsidian glasses involves certain processes that also occur during the corrosion of nuclear waste glasses. The reactions and processes that control basalt glass dissolution are similar to those that are important in nuclear waste glass dissolution. The key reaction of the overall corrosion mechanism is network hydrolysis, which eventually breaks down the glass network structure that remains after the initial ion-exchange and diffusion processes. This review also highlights some unresolved issues related to the application of an analogue approach to predicting long-term behavior of nuclear waste glass corrosion, such as discrepancies between experimental and field-based estimates of kinetic parameters for basaltic glasses

  11. Natural analogues of nuclear waste glass corrosion.

    Energy Technology Data Exchange (ETDEWEB)

    Abrajano, T.A. Jr.; Ebert, W.L.; Luo, J.S.

    1999-01-06

    This report reviews and summarizes studies performed to characterize the products and processes involved in the corrosion of natural glasses. Studies are also reviewed and evaluated on how well the corrosion of natural glasses in natural environments serves as an analogue for the corrosion of high-level radioactive waste glasses in an engineered geologic disposal system. A wide range of natural and experimental corrosion studies has been performed on three major groups of natural glasses: tektite, obsidian, and basalt. Studies of the corrosion of natural glass attempt to characterize both the nature of alteration products and the reaction kinetics. Information available on natural glass was then compared to corresponding information on the corrosion of nuclear waste glasses, specifically to resolve two key questions: (1) whether one or more natural glasses behave similarly to nuclear waste glasses in laboratory tests, and (2) how these similarities can be used to support projections of the long-term corrosion of nuclear waste glasses. The corrosion behavior of basaltic glasses was most similar to that of nuclear waste glasses, but the corrosion of tektite and obsidian glasses involves certain processes that also occur during the corrosion of nuclear waste glasses. The reactions and processes that control basalt glass dissolution are similar to those that are important in nuclear waste glass dissolution. The key reaction of the overall corrosion mechanism is network hydrolysis, which eventually breaks down the glass network structure that remains after the initial ion-exchange and diffusion processes. This review also highlights some unresolved issues related to the application of an analogue approach to predicting long-term behavior of nuclear waste glass corrosion, such as discrepancies between experimental and field-based estimates of kinetic parameters for basaltic glasses.

  12. Elaboración del duelo de una madre cuyo hijo trabajaba como sicario en Ciudad Juárez, Chihuahua

    Directory of Open Access Journals (Sweden)

    Rosalía Delgado Durán

    2014-01-01

    Full Text Available El presente trabajo es parte de una investigación cualitativa sobre el proceso de ela - boración de duelo de la madre de un sicario en el contexto de una terapia Gestalt. Se utilizó para su análisis la perspectiva de las etapas del duelo de Kübler-Ross (2006:59- 119. La exacerbación de la violencia generada en buena medida por pugnas entre gru - pos del crimen organizado en Ciudad Juárez, Chihuahua (Martínez, 2008, ha dado como resultado una gran cantidad de muertes, una de ellas es el caso que nos ocupa. Si bien uno de los objetivos iniciales de la investigación era documentar y analizar las etapas en el desarrollo del duelo de una madre a partir del fallecimiento de su hijo, este se replanteó durante el transcurso de la misma, ya que una de las características del duelo de esta madre es que inició justo cuando se enteró del trabajo que él realizaba.

  13. ANÁLISIS DE LA CALIDAD DEL AGUA EN LAS LAGUNAS DE BUSTILLOS Y DE LOS MEXICANOS (CHIHUAHUA, MÉXICO

    Directory of Open Access Journals (Sweden)

    Jesús Pilar Amado Álvarez

    2016-01-01

    Full Text Available En la parte central del estado de Chihuahua (México se encuentra la cuenca de drenaje que alimenta las lagunas endorreicas de Bustillos, y de los Mexicanos. Estos humedales de especial interés ambiental, se encuentran amenazados por una fuerte presión de actividades humanas. Para este trabajo se han planteado una serie de análisis químicos, físicos y microbiológicos, que determinan unos elevados índices de contaminación en estos hábitats acuáticos. Los resultados han mostrado bajos índices de oxígeno disuelto y elevadas concentraciones en nitratos y bacterias coliformes en el agua. Se ha detectado que las principales fuentes de contaminación de estos recursos hídricos son las actividades agropecuarias, los vertidos de aguas residuales de las áreas urbanas y, en mayor medida, por los desechos de los tratamientos industriales.

  14. Propuesta de Rehabilitación Urbana para la Colonia Tarahumara en Ciudad Cuauhtémoc, Chihuahua, México.

    Directory of Open Access Journals (Sweden)

    Leticia Peña Barrera

    2014-12-01

    El gobierno del Estado de Chihuahua, interesado en apoyar a comunidades tarahumaras o rarámuris, promueve la creación de la Colonia Tarahumara en la ciudad de Cuauhtémoc, donando en 2001 el terreno y el financiamiento para las primeras 50 viviendas en propiedad común, y así lograr su arraigo. En este trabajo se presenta la propuesta de reequipamiento urbano-ecológico de la Colonia Tarahumara, la cual fue presentada a la Fundación Tarahumara para la construcción de otras 50 unidades de vivienda, teniendo en cuenta factores determinantes de localización e identificación de las costumbres de la comunidad rarámuri, como también soluciones urbano-bioclimáticas, con el fin de que ésta pueda tener acceso a la financiación federal de la Sedesol y, por último, de contribuir al desarrollo sostenible de la comunidad tarahumara.

  15. Integrated petrographic and geochemical study of coal and gas shales from the Sabinas and Chihuahua basins, North of Mexico: estimation of methane gas resources

    International Nuclear Information System (INIS)

    De La O Burrola, Francisco

    2013-01-01

    This comprehensive characterization study was performed using organic petrology and geochemistry conducted in the Sabinas basin and Chihuahua in northern Mexico. This information allowed a numerical modeling of gas formation, considering the thermal subsidence of coal and carbonaceous shales. The objectives of this thesis are: - Establish a characterization methodology for the studied rocks - Estimate potential gas generator and its regional distribution - Estimate the methane gas resources For the development of this project, we conducted an intensive campaign representative sampling of coal, carbonaceous shales and coal gas 'in situ'. For the Sabinas basin were studied 97 samples and 114 samples in the basin of Chihuahua. The analyses carried out that were used on the samples analyzed allowed to characterize the kerogen and gas. The methodology used to cross petrographic and geochemical information to analyze the petroleum system by numerical modeling. Analyses were: Petrographic, reflectance %Ro, elemental analysis and immediate, Rock Eval6 R (Bulk rock), isotopic analysis, δ 13 C, δD, (coal gas), scanning electron microscopy, image analysis and analysis of macerals fluid inclusions. The analyzes that were used on the samples allowed to characterize the sample, the kerogen and gas. The methodology used to cross petrographic and geochemical information for analyze the oil system by numerical modeling. Analyses were: Petrographic, reflectance %Ro, elemental analysis and immediate, Rock Eval6 R (Bulk rock), isotopic analysis, δ 13 C, δD, (coal gas), scanning electron microscopy, image analysis and analysis of macerals fluid inclusions A computer program was constructed to cross the information with the analysis of samples of artificial maturation experiments in the laboratory. This approach allowed estimation of methane gas resources generated by coal and carbonaceous shales. The main results obtained for Sabinas Basin were: - The kerogen of the

  16. Uranium-238 and thorium-232 series concentrations in soil, radon-222 indoor and drinking water concentrations and dose assessment in the city of Alameda, Chihuahua, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Colmenero Sujo, L.; Montero Cabrera, M.E. E-mail: elena.montero@cimav.edu.mx; Villalba, L.; Renteria Villalobos, M.; Torres Moye, E.; Garcia Leon, M.; Garcia-Tenorio, R.; Mireles Garcia, F.; Herrera Peraza, E.F.; Sanchez Aroche, D

    2004-07-01

    High-resolution gamma spectrometry was used to determine the concentration of {sup 40}K, {sup 238}U and {sup 232}Th series in soil samples taken from areas surrounding the city of Aldama, in Chihuahua. Results of indoor air short-time sampling, with diffusion barrier charcoal detectors, revealed relatively high indoor radon levels, ranging from 29 to 422 Bq/m{sup 3}; the radon concentrations detected exceeded 148 Bq/m{sup 3} in 76% of the homes tested. Additionally, liquid scintillation counting showed concentrations of radon in drinking water ranging from 4.3 to 42 kBq/m{sup 3}. The high activity of {sup 238}U in soil found in some places may be a result of the uranium milling process performed 20 years ago in the area. High radon concentrations indoor and in water may be explained by assuming the presence of uranium-bearing rocks underneath of the city, similar to a felsic dike located near Aldama. The estimated annual effective dose of gamma radiation from the soil and radon inhalation was 3.83 mSv.

  17. Los cambios en la estructura intraurbana de Ciudad Juárez, Chihuahua, de monocéntrica a multicéntrica

    Directory of Open Access Journals (Sweden)

    César M. Flores Fuentes

    2001-01-01

    Full Text Available El artículo tiene como objetivo analizar los cambios en la estructura intraurbana de Ciudad Juárez, Chihuahua, durante el periodo 1989-1993. Para ello se usaron los censos económicos de comercio y servicios de 1989 y 1994, el censo de población de 1990 y el conteo de población de1995, ambos a nivel de AGEB. Lo anterior fue posible mediante la construcción del índice de centralidad. En 1989 la estructura intraurbana de Ciudad Juárez mostró la presencia de dos centros principales. Dichos centros, aunque con la misma jerarquía urbana, tienen distintas funciones, como resultado de contar con ramas económicas que tienen diferentes áreas de mercado, desigual densidad poblacional y distinta capacidad de compra de sus principales consumidores. Para 1994 la ciudad siguió teniendo esos dos centros principales, aunque se crearon tres nuevos subcentros que se localizan fuera de las tradicionales áreas centrales, en zonas de fácil acceso y buena infraestructura. En este contexto, la estructura intraurbana se encuentra en proceso de convertirse de monocéntrica en multicéntrica

  18. Uranium-238 and thorium-232 series concentrations in soil, radon-222 indoor and drinking water concentrations and dose assessment in the city of Aldama, Chihuahua, Mexico.

    Science.gov (United States)

    Colmenero Sujo, L; Montero Cabrera, M E; Villalba, L; Rentería Villalobos, M; Torres Moye, E; García León, M; García-Tenorio, R; Mireles García, F; Herrera Peraza, E F; Sánchez Aroche, D

    2004-01-01

    High-resolution gamma spectrometry was used to determine the concentration of 40K, 238U and 232Th series in soil samples taken from areas surrounding the city of Aldama, in Chihuahua. Results of indoor air short-time sampling, with diffusion barrier charcoal detectors, revealed relatively high indoor radon levels, ranging from 29 to 422 Bq/m3; the radon concentrations detected exceeded 148 Bq/m3 in 76% of the homes tested. Additionally, liquid scintillation counting showed concentrations of radon in drinking water ranging from 4.3 to 42 kBq/m3. The high activity of 238U in soil found in some places may be a result of the uranium milling process performed 20 years ago in the area. High radon concentrations indoor and in water may be explained by assuming the presence of uranium-bearing rocks underneath of the city, similar to a felsic dike located near Aldama. The estimated annual effective dose of gamma radiation from the soil and radon inhalation was 3.83 mSv.

  19. Three-dimensional hydrogeologic framework model of the Rio Grande transboundary region of New Mexico and Texas, USA, and northern Chihuahua, Mexico

    Science.gov (United States)

    Sweetkind, Donald S.

    2017-09-08

    As part of a U.S. Geological Survey study in cooperation with the Bureau of Reclamation, a digital three-dimensional hydrogeologic framework model was constructed for the Rio Grande transboundary region of New Mexico and Texas, USA, and northern Chihuahua, Mexico. This model was constructed to define the aquifer system geometry and subsurface lithologic characteristics and distribution for use in a regional numerical hydrologic model. The model includes five hydrostratigraphic units: river channel alluvium, three informal subdivisions of Santa Fe Group basin fill, and an undivided pre-Santa Fe Group bedrock unit. Model input data were compiled from published cross sections, well data, structure contour maps, selected geophysical data, and contiguous compilations of surficial geology and structural features in the study area. These data were used to construct faulted surfaces that represent the upper and lower subsurface hydrostratigraphic unit boundaries. The digital three-dimensional hydrogeologic framework model is constructed through combining faults, the elevation of the tops of each hydrostratigraphic unit, and boundary lines depicting the subsurface extent of each hydrostratigraphic unit. The framework also compiles a digital representation of the distribution of sedimentary facies within each hydrostratigraphic unit. The digital three-dimensional hydrogeologic model reproduces with reasonable accuracy the previously published subsurface hydrogeologic conceptualization of the aquifer system and represents the large-scale geometry of the subsurface aquifers. The model is at a scale and resolution appropriate for use as the foundation for a numerical hydrologic model of the study area.

  20. Analogue Hawking radiation from astrophysical black-hole accretion

    International Nuclear Information System (INIS)

    Das, Tapas K

    2004-01-01

    We show that spherical accretion onto astrophysical black holes can be considered as a natural example of an analogue system. We provide, for the first time, an exact analytical scheme for calculating the analogue Hawking temperature and surface gravity for general relativistic accretion onto astrophysical black holes. Our calculation may bridge the gap between the theory of transonic astrophysical accretion and the theory of analogue Hawking radiation. We show that the domination of the analogue Hawking temperature over the actual Hawking temperature may be a real astrophysical phenomenon, though observational tests of this fact will at best be difficult and at worst might prove to be impossible. We also discuss the possibilities of the emergence of analogue white holes around astrophysical black holes. Our calculation is general enough to accommodate accreting black holes with any mass

  1. Analogues of uracil nucleosides with intrinsic fluorescence (NIF-analogues): synthesis and photophysical properties.

    Science.gov (United States)

    Segal, Meirav; Fischer, Bilha

    2012-02-28

    Uridine cannot be utilized as fluorescent probe due to its extremely low quantum yield. For improving the uracil fluorescence characteristics we extended the natural chromophore at the C5 position by coupling substituted aromatic rings directly or via an alkenyl or alkynyl linker to create fluorophores. Extension of the uracil base was achieved by treating 5-I-uridine with the appropriate boronic acid under the Suzuki coupling conditions. Analogues containing an alkynyl linker were obtained from 5-I-uridine and the suitable boronic acid in a Sonogashira coupling reaction. The uracil fluorescent analogues proposed here were designed to satisfy the following requirements: a minimal chemical modification at a position not involved in base-pairing, resulting in relatively long absorption and emission wavelengths and high quantum yield. 5-((4-Methoxy-phenyl)-trans-vinyl)-2'-deoxy-uridine, 6b, was found to be a promising fluorescent probe. Probe 6b exhibits a quantum yield that is 3000-fold larger than that of the natural chromophore (Φ 0.12), maximum emission (478 nm) which is 170 nm red shifted as compared to uridine, and a Stokes shift of 143 nm. In addition, since probe 6b adopts the anti conformation and S sugar puckering favored by B-DNA, it makes a promising nucleoside analogue to be incorporated in an oligonucleotide probe for detection of genetic material.

  2. Analogue to Digital and Digital to Analogue (AD/DA) Conversion Techniques: An Overview

    CERN Multimedia

    CERN. Geneva

    2002-01-01

    The basic ideas behind modern Analogue to Digital and Digital to Analogue (AD/DA) conversion methods will be introduced: a general view of the importance of these devices will be given, along with the digital representation of time-varying, real-world analogue signals. Some CERN applications will be outlined. The variety of conversion methods, their limitations, error sources and measurement methods will form the major part of this presentation. A review of the technological progress in this field over the last 30 years will be presented, concluding with the present 'state of the art' and a quick look at what is just around the corner. This Technical Training Seminar is in the framework of the FEED-2002 Lecture Series, and it is a prerequisite to attending to any of the FEED-2002 Terms. FEED-2002 is a two-term course that will review the techniques dealing with closed loop systems, focussing on time-invariant linear systems. (free attendance, no registration required) More information on the FEED-2002 ...

  3. The Greenland Analogue Project (GAP). Literature review of hydrogeology/ hydrogeochemistry

    International Nuclear Information System (INIS)

    Wallroth, Thomas; Lokrantz, Hanna; Rimsa, Andrius

    2010-09-01

    This report is produced as part of the Greenland Analogue Project (GAP), carried out as a collaboration project with the Canadian Nuclear Waste Management Organization (NWMO), Posiva Oy and the Swedish Nuclear Fuel and Waste Management Co (SKB). The overall aim of the project is to improve the current understanding of hydrogeological and hydrogeochemical processes associated with continental-scale glacial periods including with the presence of permafrost and the advance/retreat of ice sheets. The project will focus on studying how an ice sheet affects groundwater flow and water chemistry around a deep geological repository in crystalline bedrock. The Greenland Analogue Project consists of three active sub-projects (A-C) with individual objectives. Field studies are conducted in the Kangerlussuaq region, in central Western Greenland. Sub-projects A and B collectively aim at improving the understanding of ice sheet hydrology by combining investigations on surface water processes with ice sheet drilling and instrumentation. In sub-project C, the penetration of glacial melt water into the bedrock, groundwater flow and the chemical composition of water will be studied. Main planned activities in sub-project C include drilling of a deep borehole in front of the ice sheet, in which different downhole surveys, sampling and monitoring will be carried out. The primary aim of this report is to review available information about hydrogeology and hydrogeochemistry in central Western Greenland, with special emphasis on the area around Kangerlussuaq. The relevant information about this area is however very limited, and it was decided to extend the review to briefly include studies made in other regions with similar conditions in terms of geology, climate and glaciology. The number of published studies made in other areas with glaciers, ice sheets or permafrost is very large, and the review and list of references in this report is far from complete. It is also obvious that both

  4. The Greenland Analogue Project (GAP). Literature review of hydrogeology/ hydrogeochemistry

    Energy Technology Data Exchange (ETDEWEB)

    Wallroth, Thomas; Lokrantz, Hanna; Rimsa, Andrius (Bergab Consulting Geologists, Goeteborg (Sweden))

    2010-09-15

    This report is produced as part of the Greenland Analogue Project (GAP), carried out as a collaboration project with the Canadian Nuclear Waste Management Organization (NWMO), Posiva Oy and the Swedish Nuclear Fuel and Waste Management Co (SKB). The overall aim of the project is to improve the current understanding of hydrogeological and hydrogeochemical processes associated with continental-scale glacial periods including with the presence of permafrost and the advance/retreat of ice sheets. The project will focus on studying how an ice sheet affects groundwater flow and water chemistry around a deep geological repository in crystalline bedrock. The Greenland Analogue Project consists of three active sub-projects (A-C) with individual objectives. Field studies are conducted in the Kangerlussuaq region, in central Western Greenland. Sub-projects A and B collectively aim at improving the understanding of ice sheet hydrology by combining investigations on surface water processes with ice sheet drilling and instrumentation. In sub-project C, the penetration of glacial melt water into the bedrock, groundwater flow and the chemical composition of water will be studied. Main planned activities in sub-project C include drilling of a deep borehole in front of the ice sheet, in which different downhole surveys, sampling and monitoring will be carried out. The primary aim of this report is to review available information about hydrogeology and hydrogeochemistry in central Western Greenland, with special emphasis on the area around Kangerlussuaq. The relevant information about this area is however very limited, and it was decided to extend the review to briefly include studies made in other regions with similar conditions in terms of geology, climate and glaciology. The number of published studies made in other areas with glaciers, ice sheets or permafrost is very large, and the review and list of references in this report is far from complete. It is also obvious that both

  5. Use of analogues to build technologists' confidence: NAnet

    International Nuclear Information System (INIS)

    Noseck, Ulrich

    2008-01-01

    The relevance of analogues to radioactive waste management stems from the long timescales that have to be considered. Periods up to a million or more years into the future need to be considered and these are beyond experimental investigation and human experience. Within the last years the term 'Natural Analogue' has got a much wider meaning and includes man-made analogues as well. The role of natural analogues in the safety case depends amongst others on the time scale to be covered. Therefore, it is useful to classify them by the time period addressed in the study. Here it is referred to: industrial analogues which started earliest 150 years ago, archaeological analogues, which cover time frames between the past 10 000 and 150 years, and geological analogues, which usually cover time frames of more than 10 000 years and in most cases more than million years. The current interest in analogues in different countries is reflected by several recent review projects with emphasis on the application of natural analogue study results in performance assessment. The most recent international review was performed within the 5. EURATOM Framework of the EC by the NAnet project, a network on the review of natural analogue studies with emphasis on the application of analogues in long-term safety assessment and communication. The overall aim of the NAnet project was to review the past and present use and understanding of natural analogues, and to make recommendations for their future use. The project covered 'traditional' natural analogue studies, such as large-scale investigations of radionuclide transport around uranium ore bodies, and process or mechanistic analogue studies such as those examining natural glass and bentonite clay stability. To complete the picture, a restricted range of other studies of natural systems which employ a similar philosophy to analogues was also included in the scope. These included studies which have examined radionuclide transport and retardation

  6. Synthesis and biological evaluation of enantiomerically pure cyclopropyl analogues of combretastatin A4.

    Science.gov (United States)

    Ty, Nancy; Pontikis, Renée; Chabot, Guy G; Devillers, Emmanuelle; Quentin, Lionel; Bourg, Stéphane; Florent, Jean-Claude

    2013-03-01

    To evaluate the influence of stereochemistry on biological activities of cis-cyclopropyl combretastatin A4 (CA4) analogues, we have prepared several cyclopropyl compounds in their pure enantiomeric forms. The key reactions in our synthesis are the cyclopropanation of a (Z)-alkenylboron compound bearing a chiral auxiliary, and the cross-coupling of both enantiomeric cyclopropyl trifluoroborate salts with aryl and olefinic halides. Three pairs of cis-cyclopropyl CA4 analogues were evaluated for their potential antivascular activities. The diarylcyclopropyl compounds with SR-configuration (-)-1b, (-)-2b and the cyclopropylvinyl enantiomer (+)-3a with RR-configuration were the most potent tubulin polymerization inhibitors. A correlation was noted between anti-tubulin activity and rounding up activity of endothelial cells. The cytotoxic activity on B16 melanoma cells was in the submicromolar range for most compounds, but unlike the anti-tubulin activity, there was no difference in cytotoxic activity between racemic and enantiomerically pure forms for the three series of compounds. Molecular docking studies within the colchicine binding site of tubulin were in good agreement with the tubulin polymerization inhibitory data and confirmed the importance of the configuration of the synthesized cis-cyclopropyl CA4 analogues for potential antivascular activities. Copyright © 2013. Published by Elsevier Ltd.

  7. A chemoselective and continuous synthesis of m-sulfamoylbenzamide analogues

    Directory of Open Access Journals (Sweden)

    Arno Verlee

    2017-02-01

    Full Text Available For the synthesis of m-sulfamoylbenzamide analogues, small molecules which are known for their bioactivity, a chemoselective procedure has been developed starting from m-(chlorosulfonylbenzoyl chloride. Although a chemoselective process in batch was already reported, a continuous-flow process reveals an increased selectivity at higher temperatures and without catalysts. In total, 15 analogues were synthesized, using similar conditions, with yields ranging between 65 and 99%. This is the first automated and chemoselective synthesis of m-sulfamoylbenzamide analogues.

  8. A Low-cost Multi-channel Analogue Signal Generator

    CERN Document Server

    Müller, F; The ATLAS collaboration; Shen, W; Stamen, R

    2009-01-01

    A scalable multi-channel analogue signal generator is presented. It uses a commercial low-cost graphics card with multiple outputs in a standard PC as signal source. Each color signal serves as independent channel to generate an analogue signal. A custom-built external PCB was developed to adjust the graphics card output voltage levels for a specific task, which needed differential signals. The system furthermore comprises a software package to program the signal shape. The signal generator was successfully used as independent test bed for the ATLAS Level-1 Trigger Pre-Processor, providing up to 16 analogue signals.

  9. Conjugate dynamical systems: classical analogue of the quantum energy translation

    International Nuclear Information System (INIS)

    Torres-Vega, Gabino

    2012-01-01

    An aspect of quantum mechanics that has not been fully understood is the energy shift generated by the time operator. In this study, we introduce the use of the eigensurfaces of dynamical variables and commutators in classical mechanics to study the classical analogue of the quantum translation of energy. We determine that there is a conjugate dynamical system that is conjugate to Hamilton's equations of motion, and then we generate the analogue of the time operator and use it in the translation of points along the energy direction, i.e. the classical analogue of the Pauli theorem. The theory is illustrated with a nonlinear oscillator model. (paper)

  10. Desarrollo de un destino de turismo médico en el contexto de la frontera México-Estados Unidos: el caso de Ciudad Juárez, Chihuahua, México

    OpenAIRE

    Martínez Almanza, María Teresa

    2016-01-01

    La asistencia sanitaria es uno de los temas primordiales del siglo XXI. Los problemas relacionados con la atención médica contemporánea han generado una creciente demanda de servicios de pacientes extranjeros. En el marco de la teoría fundamentada, mediante 69 entrevistas en profundidad, realizadas de 2013 a 2015, se analiza el proceso de desarrollo de Ciudad Juárez, Chihuahua, México como un destino turístico médico de frontera. Se presenta una narrativa de la génesis y evolución del caso d...

  11. Long-term predictions using natural analogues

    International Nuclear Information System (INIS)

    Ewing, R.C.

    1995-01-01

    One of the unique and scientifically most challenging aspects of nuclear waste isolation is the extrapolation of short-term laboratory data (hours to years) to the long time periods (10 3 -10 5 years) required by regulatory agencies for performance assessment. The direct validation of these extrapolations is not possible, but methods must be developed to demonstrate compliance with government regulations and to satisfy the lay public that there is a demonstrable and reasonable basis for accepting the long-term extrapolations. Natural systems (e.g., open-quotes natural analoguesclose quotes) provide perhaps the only means of partial open-quotes validation,close quotes as well as data that may be used directly in the models that are used in the extrapolation. Natural systems provide data on very large spatial (nm to km) and temporal (10 3 -10 8 years) scales and in highly complex terranes in which unknown synergisms may affect radionuclide migration. This paper reviews the application (and most importantly, the limitations) of data from natural analogue systems to the open-quotes validationclose quotes of performance assessments

  12. Can stroke patients use visual analogue scales?

    Science.gov (United States)

    Price, C I; Curless, R H; Rodgers, H

    1999-07-01

    Visual analogue scales (VAS) have been used for the subjective measurement of mood, pain, and health status after stroke. In this study we investigated how stroke-related impairments could alter the ability of subjects to answer accurately. Consent was obtained from 96 subjects with a clinical stroke (mean age, 72.5 years; 50 men) and 48 control subjects without cerebrovascular disease (mean age, 71.5 years; 29 men). Patients with reduced conscious level or severe dysphasia were excluded. Subjects were asked to rate the tightness that they could feel on the (unaffected) upper arm after 3 low-pressure inflations with a standard sphygmomanometer cuff, which followed a predetermined sequence (20 mm Hg, 40 mm Hg, 0 mm Hg). Immediately after each change, they rated the perceived tightness on 5 scales presented in a random order: 4-point rating scale (none, mild, moderate, severe), 0 to 10 numerical rating scale, mechanical VAS, horizontal VAS, and vertical VAS. Standard tests recorded deficits in language, cognition, and visuospatial awareness. Inability to complete scales with the correct pattern was associated with any stroke (P<0.001). There was a significant association between success using scales and milder clinical stroke subtype (P<0.01). Within the stroke group, logistic regression analysis identified significant associations (P<0.05) between impairments (cognitive and visuospatial) and inability to complete individual scales correctly. Many patients after a stroke are unable to successfully complete self-report measurement scales, including VAS.

  13. Identification and applicability of analogues for a safety case for a HLW repository in evaporites: results from a NEA workshop

    Energy Technology Data Exchange (ETDEWEB)

    Noseck, U.; Wolf, J. [Gesellschaft für Anlagen und Reaktorsicherheit (GRS) mbH, Brunswick (Germany); Steininger, W. [Project Management Agency Karslruhe Water Technology and Waste Management, PTKA-WTE, Karlsruhe Institute of Technology, KIT, Eggenstein-Leopoldshafen (Germany); Miller, B. [AMEC, The Renaissance Center, Warrington (United Kingdom)

    2015-06-15

    A workshop was held in September 2012 in Braunschweig, Germany, to discuss the potential for natural and anthropogenic analogue studies to contribute to safety cases for radioactive waste repositories constructed in salt formations. Presentations were given on many analogue sites and systems from different countries. Discussions at the workshop then addressed the following aspects that are particularly relevant to the safety concept for radioactive waste disposal in salt: (1) the long-term integrity of rock salt formations, (2) the integrity of technical barriers, and (3) microbial, chemical and transport processes. A diverse range of natural systems were discussed as potential analogues for the integrity of rock salt. These included the deformation of anhydrite layers in rock salt; the response of rock salt to mechanical and thermal loads; and the isotopic signatures of syngenetic waters contained in fluid inclusions. Some anthropogenic examples drawn from the oil and gas industries, and from hazardous waste disposal, were proposed as analogues for the integrity of (geo)technical barriers. A broad range of studies on natural and anthropogenic salt-brine systems were identified as potential analogues for the radionuclide sorption and (co)precipitation process that may take place in the repository near and far fields, as well as for understanding the significance of hydrocarbons and microbial processes. It was evident from discussions at the workshop that there are some specific technical issues that may benefit from further analogue study, particularly the compaction of crushed salt backfill, the viability of microbes in the near-field, the stability of plugs and seals, the deformation of anhydrite, and isotope signatures in fluid inclusions. (authors)

  14. Relación entre consultas a urgencias por enfermedad respiratoria y contaminación atmosférica en Ciudad Juárez, Chihuahua

    Directory of Open Access Journals (Sweden)

    Hernández-Cadena Leticia

    2000-01-01

    Full Text Available OBJETIVO: Analizar la relación entre las concentraciones ambientales de partículas de diámetro <=10 µm (PM10 y de ozono con el número diario de consultas al servicio de urgencias por enfermedades respiratorias agudas y asma en niños menores de 15 años, residentes de Ciudad Juárez, Chihuahua, México. MATERIAL Y MÉTODOS: Este estudio se realizó durante los años de 1998 y 1999, utilizando un diseño de tipo ecológico. Los datos atmosféricos se obtuvieron de la base de datos de la Agencia de Protección al Ambiente (EPA, provenientes de ocho estaciones de monitoreo ubicadas en Ciudad Juárez y en El Paso, Texas. Los datos de consultas al servicio de urgencias por causas respiratorias se obtuvieron de los registros médicos de dos hospitales del Instituto Mexicano del Seguro Social (IMSS, en Ciudad Juárez, Chihuahua, de julio de 1997 a diciembre de 1998. Los diagnósticos se clasificaron en dos grupos: a asma, y b infecciones respiratorias altas, conforme a la Clasificación Internacional de Enfermedades (CIE-9 o CIE-10. El análisis se realizó con la utilización de la metodología de series de tiempo que emplea regresión Poisson. RESULTADOS: Durante el periodo de estudio la media de 24 horas de PM10 fue de 34.46 µg/m³ (DE=17.99 y la media de los niveles de ozono fue de 51.60 partes por billón (ppb (DE=20.70. El modelo propuesto estima que un incremento de 20 µg/m³ en el promedio de 24 horas, en la exposición a PM10, se relaciona con un incremento de 4.97% (IC 95% 0.97-9.13 en las consultas por asma con un retraso de cinco días y con un incremento de 9% (IC 95% 1.8-16.8 cuando se considera a la exposición acumulada de cinco días anteriores. Respecto a enfermedades respiratorias altas se encontró un aumento de 2.95% en las consultas a urgencias por cada 20 µm/m³ de incremento en el promedio de 24 horas en la exposición a PM10. Se observó que el impacto de PM10 sobre las visitas de urgencia por asma fue más severo en

  15. Prevalencia de asma y otras enfermedades alérgicas en niños escolares de Ciudad Juárez, Chihuahua

    Directory of Open Access Journals (Sweden)

    Barraza-Villarreal Albino

    2001-01-01

    Full Text Available Objetivo. Determinar la prevalencia y severidad del asma, de la rinitis y del eczema en escolares. Material y métodos. Estudio transversal efectuado entre abril de 1998 y mayo de 1999 en Ciudad Juárez, Chihuahua, México, a una muestra aleatoria de 6 174 niños de 53 escuelas. Se aplicó la metodología propuesta por el International Study of Asthma and Allergies in Childhood (ISAAC (etapas 1 y 2 para determinar la prevalencia y severidad del asma, rinitis y eczema. La información de prevalencia, tanto actual como acumulada para dichos padecimientos, se obtuvo mediante un cuestionario ya estandarizado y contestado por los padres de los niños. El diseño de la muestra se hizo por un muestreo mixto, en el cual se estratificó por nivel de contaminación ambiental. Se estimaron prevalencias actual y acumulada estratificando por grupo de edad, sexo, área e historia familiar de asma. Resultados. La prevalencia acumulada de asma por diagnóstico médico y sibilancia (silbidos fue de 6.8% (IC95% 6.2-7.4 y 20.% (IC95% 19.7-21.8, respectivamente; la prevalencia de sibilancia en los últimos 12 meses fue mayor en el grupo de 6-8 años que en el de 11-14 años(9.7% contra 5.8% (phttp://www.insp.mx/salud/index.html

  16. Pronóstico productivo de la avena forrajera de temporal por efecto del cambio climático en el noroeste de Chihuahua, México

    Directory of Open Access Journals (Sweden)

    Daniel Villazón Bustillos

    2017-01-01

    Full Text Available El cambio climático puede afectar la productividad de los cultivos en una región determinada. El objetivo fue identificar la variabilidad en la producción de avena forrajera ( Avena sativa L. de temporal utilizando una función estocástica y analizar sus relaciones con la temperatura y precipitación, ante escenarios de cambio climático en la región noroeste de Chihuahua, México. Se obtuvo información estadística de 13 años (2001 - 2013 en las estaciones meteorológicas de los municipios de Bachíniva y Namiquipa utilizando la información de julio, agosto y septiembre, en cuyo periodo se concentra alrededor del 80% de la precipitación anual. Se tomó información del modelo HadCM3 (Modelo acoplado del Centro Hadley versión 3, 2001 que describe el comportamiento de variables climáticas bajo escenarios de emisión de contaminantes A2 y B2 para los años 2050 y 2080. Los cambios en las variables climáticas en el corto plazo (2050 se esperan con un aumento tanto en la temperatur a como en la precipitación, lo que permite en el caso de Bachíniva mejorar la producción de avena de 3.57 t/ha a 8.11 t/ha bajo en escenario de emisión de contaminantes A2. A largo plazo (2080 se espera un incremento permanente en la temperatura y sin imp ortar que tanto mejore la precipitación, esto provocara que en las actuales regiones productoras de avena no se logren desarrollar los cultivos para su cosecha.

  17. La estructura urbana y las diferencias espaciales en el tiempo de traslado del viaje al trabajo en Ciudad Juárez, Chihuahua

    Directory of Open Access Journals (Sweden)

    César M. Fuentes Flores

    2008-01-01

    Full Text Available Este artículo tiene como objetivo analizar las diferencias intraurbanas en los tiempos de traslado del viaje al trabajo en transporte público y privado, asociado a variables de uso del suelo (razón empleo/viviendas, densidad de población, valor del suelo, a características socioeconómicas (proporción de población con ingreso bajo y alto, y a la tenencia de la vivienda (proporción de viviendas propias y rentadas en Ciudad Juárez, Chihuahua. Las variables fueron construidas con información de la Encuesta de Origen-Destino 1997 (IMIP, el XII Censo de Ppoblación y Vivienda 2000 (INEEGI y el XIII Censo Económico 1999 (INEEGI a nivel de AGEB. El análisis se realizó mediante la construcción de cuatro modelos de regresión que se estimaron mediante la técnica de mínimos cuadrados ordinarios. Los resultados muestran que las variables razón empleo/viviendas, valor del suelo, y proporción de viviendas rentadas son estadísticamente significativas para explicar menores tiempos de traslado en transporte público. En contraste, la densidad de población y la proporción de viviendas propias son estadísticamente significativas para explicar menores tiempos de traslado en transporte público. La proporción de población de bajos ingresos es estadísticamente significativa para explicar los cambios en los tiempos de traslado en transporte privado.

  18. Glucagon-like peptide-1 analogues: An overview

    Directory of Open Access Journals (Sweden)

    Vishal Gupta

    2013-01-01

    Full Text Available Abnormalities of the incretin axis have been implicated in the pathogenesis of type 2 diabetes mellitus. Glucagon-like peptide-1 (GLP-1 and gastroinhibitory intestinal peptide constitutes >90% of all the incretin function. Augmentation of GLP-1 results in improvement of beta cell health in a glucose-dependant manner (post-prandial hyperglycemia and suppression of glucagon (fasting hyperglycemia, amongst other beneficial pleiotropic effects. Native GLP-1 has a very short plasma half-life and novel methods have been developed to augment its half life, such that its anti-hyperglycemic effects can be exploited. They can be broadly classified as exendin-based therapies (exenatide, exenatide once weekly, DPP-4-resistant analogues (lixisenatide, albiglutide, and analogues of human GLP-1 (liraglutide, taspoglutide. Currently, commercially available analogues are exenatide, exenatide once weekly, and liraglutide. This review aims to provide an overview of most GLP-1 analogues.

  19. an assessment of billing electricity consumers via analogue meters

    African Journals Online (AJOL)

    DR. AMINU

    ABSTRACT. This paper assesses the perception of billing consumers via analogue meter in Kano Electricity ... the successor companies of Power Holding Company ... Nassarawa computer center was established in 1991. .... The value 7.2 is.

  20. Solistatinol, a novel phenolic compactin analogue from Penicillium solitum

    DEFF Research Database (Denmark)

    Larsen, Thomas Ostenfeld; Lange, Lene; Schnorr, Kirk

    2007-01-01

    Solistatinol, a novel phenolic compactin analogue, has been isolated from Penicillium solitum using a UV-guided strategy. The structure and relative stereochemistry were determined by NMR spectroscopy and mass spectrometry. The absolute stereochemistry was determined by chemical degradation...

  1. From BPA to its analogues: Is it a safe journey?

    Science.gov (United States)

    Usman, Afia; Ahmad, Masood

    2016-09-01

    Bisphenol-A (BPA) is one of the most abundant synthetic chemicals in the world due to its uses in plastics. Its widespread exposure vis-a-vis low dose effects led to a reduction in its safety dose and imposition of ban on its use in infant feeding bottles. This restriction paved the way for the gradual market entry of its analogues. However, their structural similarity to BPA has put them under surveillance for endocrine disrupting potential. The application of these analogues is increasing and so are the studies reporting their toxicity. This review highlights the reasons which led to the ban of BPA and also reports the exposure and toxicological data available on its analogues. Hence, this compilation is expected to answer in a better way whether the replacement of BPA by these analogues is safer or more harmful? Copyright © 2016. Published by Elsevier Ltd.

  2. Synthesis and antiplatelet activity of thioaryloxyacids analogues of clofibric acid.

    Science.gov (United States)

    Ammazzalorso, Alessandra; Amoroso, Rosa; Baraldi, Mario; Bettoni, Giancarlo; Braghiroli, Daniela; De Filippis, Barbara; Giampietro, Letizia; Tricca, Maria L; Vezzalini, Francesca

    2005-09-01

    The thiophene-, benzothiazole- and pyridine-thioaryloxyacids analogues of clofibric acid were synthesized and their antiplatelet activity was screened. Some compounds exhibited antiaggregating properties. The platelet-related haemostasis was measured on a PFA-100 analyzer using bull blood.

  3. Modeling of NAD+ analogues in horse liver alcohol dehydrogenase

    NARCIS (Netherlands)

    Beijer, N.A.; Buck, H.M.; Sluyterman, L.A.A.E.; Meijer, E.M.

    1990-01-01

    So far, the interactions of nicotinamide adenine dinucleotide (NAD+) derivatives with dehydrogenases are not very well understood. This hampers the introduction of NAD+ analogues with improved characteristics concerning industrial application. We have developed an AMBER molecular mechanics model in

  4. Algorithmic fundamentals of computerized tomography and of transverse analogue tomography

    International Nuclear Information System (INIS)

    Heckmann, K.

    1981-01-01

    Computerized tomography and transverse analogue tomography are two different approaches to the same goal, namely, transverse tomography. The algorithm is discussed and compared. Transverse tomography appears capable of further development, judging by this comparison. (orig.) [de

  5. Analogue and Mixed-Signal Integrated Circuits for Space Applications

    CERN Document Server

    2014-01-01

    The purpose of AMICSA 2014 (organised in collaboration of ESA and CERN) is to provide an international forum for the presentation and discussion of recent advances in analogue and mixed-signal VLSI design techniques and technologies for space applications.

  6. Kidney protection during peptide receptor radionuclide therapy with somatostatin analogues.

    NARCIS (Netherlands)

    Rolleman, E.J.; Melis, M.; Valkema, R.; Boerman, O.C.; Krenning, E.P.; Jong, M. de

    2010-01-01

    This review focuses on the present status of kidney protection during peptide receptor radionuclide therapy (PRRT) using radiolabelled somatostatin analogues. This treatment modality for somatostatin receptor-positive tumours is limited by renal reabsorption and retention of radiolabelled peptides

  7. an assessment of billing electricity consumers via analogue meters

    African Journals Online (AJOL)

    DR. AMINU

    Keywords: Electricity Distribution, Consumers, Analogue Meter, Billing, Nigeria. INTRODUCTION. Electricity ... the energy usage of a typical electricity consumer in one month is several ..... improve on distribution network. In addition it should.

  8. Insulin analogues in pregnancy and specific congenital anomalies

    DEFF Research Database (Denmark)

    de Jong, Josta; Garne, Ester; Wender-Ozegowska, Ewa

    2016-01-01

    Insulin analogues are commonly used in pregnant women with diabetes. It is not known if the use of insulin analogues in pregnancy is associated with any higher risk of congenital anomalies in the offspring compared with use of human insulin. We performed a literature search for studies of pregnant...... women with pregestational diabetes using insulin analogues in the first trimester and information on congenital anomalies. The studies were analysed to compare the congenital anomaly rate among foetuses of mothers using insulin analogues with foetuses of mothers using human insulin. Of 29 studies, we...... samples in the included studies provided insufficient statistical power to identify a moderate increased risk of specific congenital anomalies. Copyright © 2015 John Wiley & Sons, Ltd....

  9. 3-alkyl fentanyl analogues: Structure-activity-relationship study

    OpenAIRE

    Vučković, Sonja; Savić-Vujović, Katarina; Srebro, Dragana; Ivanović, Milovan; Došen-Mićović, Ljiljana; Stojanović, Radan; Prostran, Milica

    2012-01-01

    Introduction. Fentanyl belongs to 4-anilidopiperidine class of synthetic opioid analgesics. It is characterized by high potency, rapid onset and short duration of action. A large number of fentanyl analogues have been synthesized so far, both to establish the structure-activity-relationship (SAR) and to find novel, clinically useful analgesic drugs. Objective. In this study, newly synthesized 3-alkyl fentanyl analogues were examined for analgesic activity and compared with fentanyl. Methods. ...

  10. Analogue Signal Processing: Collected Papers 1994-95

    DEFF Research Database (Denmark)

    1996-01-01

    This document is a collection of the papers presented at international conferences and in international journals by the analogue signal processing group of Electronics Institute, Technical University of Denmark, in 1994 and 1995.......This document is a collection of the papers presented at international conferences and in international journals by the analogue signal processing group of Electronics Institute, Technical University of Denmark, in 1994 and 1995....

  11. Analogue Signal Processing: Collected Papers 1996-97

    DEFF Research Database (Denmark)

    1997-01-01

    This document is a collection of the papers presented at international conferences and in international journals by the analogue signal processing group of the Department of Information Technology, Technical University of Denmark, in 1996 and 1997.......This document is a collection of the papers presented at international conferences and in international journals by the analogue signal processing group of the Department of Information Technology, Technical University of Denmark, in 1996 and 1997....

  12. Synthesis of tritium labelled phosphonate analogues of sphinganine-1-phosphate

    International Nuclear Information System (INIS)

    Schick, Andreas; Schwarzmann, Guenter; Kolter, Thomas; Sandhoff, Konrad

    1997-01-01

    Tritiated phosphonate analogues 9 and 10 are prepared as analogues of sphinganine-1-phosphate 4. The key step in this synthesis is the catalytic tritiation of the triple bond in reduction of the protected diethyl-3-(S)-tert.-butoxycarbonylamino -4-hydroxy-5-tridecinyl-1-phosphonate by means of sodium boro[ 3 H]hydride as tritium source. These compounds are synthesized to study their metabolic stability and to evaluate their biological properties. (author)

  13. A Record of Uranium-Series Transport in Fractured, Unsaturated Tuff at Nopal I, Sierra Peña Blanca, Chihuahua, Mexico

    Science.gov (United States)

    Denton, J.; Goldstein, S. J.; Paviet, P.; Nunn, A. J.; Amato, R. S.; Hinrichs, K. A.

    2015-12-01

    In this study we utilize U-series disequilibria measurements to investigate mineral fluid interactions and the role fractures play in the geochemical evolution of an analogue for a high level nuclear waste repository, the Nopal I uranium ore deposit. Samples of fracture-fill materials have been collected from a vertical drill core and surface fractures. High uranium concentrations in these materials (12-7700 ppm) indicate U mobility and transport from the deposit in the past. U concentrations generally decrease with horizontal distance away from the ore deposit but show no trend with depth. Isotopic activity ratios indicate a complicated geochemical evolution in terms of the timing and extent of actinide mobility, possibly due to changing environmental (redox) conditions over the history of the deposit. 234U/238U activity ratios are generally distinct from secular equilibrium and indicate some degree of open system U behavior during the past 1.2 Ma. However, calculated closed system 238U-234U-230Th model ages are generally >313 ka and >183 ka for the surface fracture and drill core samples respectively, suggesting closed system behavior for U and Th over this most recent time period. Whole rock isochrons drawn for the drill core samples show that at two of three depths fractures have remained closed with respect to U and Th mobility for >200 ka. However, open system behavior for U in the last 350 ka is suggested at 67 m depth. 231Pa/235U activity ratios within error of unity suggest closed system behavior for U and Pa for at least the past 185 ka. 226Ra/230Th activity ratios are typically <1 (0.7-1.2), suggesting recent (<8 ka) radium loss and mobility due to ongoing fluid flow in the fractures. Overall, the mainly closed system behavior of U-Th-Pa over the past ~200 ka provides one indicator of the geochemical immobility of these actinides over long time-scales for potential nuclear waste repositories sited in fractured, unsaturated tuff.

  14. Relación entre consultas a urgencias por enfermedad respiratoria y contaminación atmosférica en Ciudad Juárez, Chihuahua Relationship between emergency room visits for respiratory disease and atmospheric pollution in Ciudad Juárez, Chihuahua

    Directory of Open Access Journals (Sweden)

    Leticia Hernández-Cadena

    2000-08-01

    Full Text Available OBJETIVO: Analizar la relación entre las concentraciones ambientales de partículas de diámetro OBJECTIVE: To assess the relationship of <=10 µm particles (PM10 and atmospheric ozone concentrations, with the daily number of emergency visits due to asthma and acute respiratory diseases, among children aged under 15, living in Ciudad Juarez, Chihuahua, Mexico. MATERIAL AND METHODS: Between 1998 and 1999, an ecologic study was conducted. Atmospheric data were obtained from the Environmental Protection Agency (EPA, from eight monitoring stations located in Ciudad Juarez, Chihuahua, and El Paso, Texas. From July 1997 to December 1998, data from emergency room visits for respiratory illness were abstracted from existing medical records of two Mexican Institute of Social Security (IMSS hospitals in Ciudad Juarez. Diagnoses were classified into two groups: a asthma, and b upper respiratory infections (URI, according to the International Classification of Diseases (ICD-9 and/or IDC-10. Statistical analysis was carried out using the Poisson regression time series method. RESULTS: During the study period, the mean 24-hour PM10 level was 34.46 µg/m³ (SD=17.99 and the mean ozone level was 51.60 ppb (SD=20.70. The model shows that an increase of 20 µg/m³ in the mean 24-hour exposure to PM10 was related to an increase of 4.97% (95% CI 0.97-9.13 in emergency visits for asthma, with a 5-day lag, as well as to an increase of 9% (95% CI 1.8-16.8 when a cumulative 5-day exposure was considered. URI increased 2.95% as a cause of emergency room visits, for each 20 µg/m³ increase in the mean 24-hour exposure to PM10. The impact of PM10 on emergency visits for asthma was greater on days with ozone ambient levels exceeded 49 ppb (median value. CONCLUSIONS: A positive association was found between environmental PM10 and ozone concentrations and the daily number of emergency room visits due to asthma and acute respiratory diseases, even with levels lower than the

  15. Unsaturated zone waters from the Nopal I natural analog, Chihuahua, Mexico -- Implications for radionuclide mobility at Yucca Mountain

    Energy Technology Data Exchange (ETDEWEB)

    Pickett, D.A.; Murphy, W.M.

    1999-07-01

    Chemical and U-Th isotopic data on unsaturated zone waters from the Nopal I natural analog reveal effects of water-rock interaction and help constrain models of radionuclide release and transport at the site and, by analogy, at the proposed nuclear waste repository at Yucca Mountain. Geochemical reaction-path modeling indicates that, under oxidizing conditions, dissolution of uraninite (spent fuel analog) by these waters will lead to eventual schoepite precipitation regardless of initial silica concentration provided that groundwater is not continuously replenished. Thus, less soluble uranyl silicates may not dominate the initial alteration assemblage and keep dissolved U concentrations low. Uranium-series activity ratios are consistent with models of U transport at the site and display varying degrees of leaching versus recoil mobilization. Thorium concentrations may reflect the importance of colloidal transport of low-solubility radionuclides in the unsaturated zone.

  16. Unsaturated zone waters from the Nopal I natural analog, Chihuahua, Mexico -- Implications for radionuclide mobility at Yucca Mountain

    International Nuclear Information System (INIS)

    Pickett, D.A.; Murphy, W.M.

    1999-01-01

    Chemical and U-Th isotopic data on unsaturated zone waters from the Nopal I natural analog reveal effects of water-rock interaction and help constrain models of radionuclide release and transport at the site and, by analogy, at the proposed nuclear waste repository at Yucca Mountain. Geochemical reaction-path modeling indicates that, under oxidizing conditions, dissolution of uraninite (spent fuel analog) by these waters will lead to eventual schoepite precipitation regardless of initial silica concentration provided that groundwater is not continuously replenished. Thus, less soluble uranyl silicates may not dominate the initial alteration assemblage and keep dissolved U concentrations low. Uranium-series activity ratios are consistent with models of U transport at the site and display varying degrees of leaching versus recoil mobilization. Thorium concentrations may reflect the importance of colloidal transport of low-solubility radionuclides in the unsaturated zone

  17. Characterisation of insulin analogues therapeutically available to patients

    KAUST Repository

    Adams, Gary G.

    2018-03-29

    The structure and function of clinical dosage insulin and its analogues were assessed. This included \\'native insulins\\' (human recombinant, bovine, porcine), \\'fast-acting analogues\\' (aspart, glulisine, lispro) and \\'slow-acting analogues\\' (glargine, detemir, degludec). Analytical ultracentrifugation, both sedimentation velocity and equilibrium experiments, were employed to yield distributions of both molar mass and sedimentation coefficient of all nine insulins. Size exclusion chromatography, coupled to multi-angle light scattering, was also used to explore the function of these analogues. On ultracentrifugation analysis, the insulins under investigation were found to be in numerous conformational states, however the majority of insulins were present in a primarily hexameric conformation. This was true for all native insulins and two fast-acting analogues. However, glargine was present as a dimer, detemir was a multi-hexameric system, degludec was a dodecamer (di-hexamer) and glulisine was present as a dimer-hexamer-dihexamer system. However, size-exclusion chromatography showed that the two hexameric fast-acting analogues (aspart and lispro) dissociated into monomers and dimers due to the lack of zinc in the mobile phase. This comprehensive study is the first time all nine insulins have been characterised in this way, the first time that insulin detemir have been studied using analytical ultracentrifugation and the first time that insulins aspart and glulisine have been studied using sedimentation equilibrium. The structure and function of these clinically administered insulins is of critical importance and this research adds novel data to an otherwise complex functional physiological protein.

  18. Quantitative structure-activity analysis of acetylcholinesterase inhibition by oxono and thiono analogues of organophosphorus compounds. (Reannouncement with new availability information)

    Energy Technology Data Exchange (ETDEWEB)

    Maxwell, D.M.; Brecht, K.M.

    1992-02-01

    A comparison of the bimolecular rate constants (ki) for inhibition of electric eel acetylcholinesterase (AChE) by the oxono (i.e., P=O) and thiono (i.e., P=S) analogues of parathion, methylparathion, leptophos, fonofos, sarin, and soman revealed that the oxono/thiono ratios of ki values varied from 14 for soman to 1240 for parathion. Analysis of the relative importance of the dissociation equilibrium constant and the phosphorylation rate constant in producing this variation in ki values indicated that the oxono analogues had phosphorylation rate constant values that varied in a narrow range from 8- to 14-fold greater than their thiono counterparts, while the oxono/thiono ratios for dissociation constants varied widely from 1 for soman to 82 for fonofos. The lower affinities of thiono analogues for AChE probably resulted from differences in the hydrophobic binding of oxono and thiono analogues to the active site of AChE, inasmuch as the hydrophobicities (i.e., octanol/water partition coefficients) of thiono organophosphorus compounds were much greater than the hydrophobicities of their oxono analogues. Quantitative structure-activity analysis indicated that the hydrophobic effects of oxono and thiono moieties correlated with log ki for AChE inhibition to a greater extent (r2 = 0.79) than their electronic effects (r2 equal to or less than 0.48). These observations suggest that the differences in hydrophobicity of oxono and thiono analogues of organophosphorus compounds may be as important as their electronic differences in determining their effectiveness as AChE inhibitors. Acetylcholinesterase, soman (GD), structure-activity analysis inhibition, oxono analogues, thiono analogues.

  19. Percepción de estudiantes de educación superior sobre sus competencias en las TIC en las universidades Autónoma de Chihuahua y Veracruzana

    Directory of Open Access Journals (Sweden)

    Carlos Arturo Torres Gastelú

    2011-10-01

    Full Text Available Las universidades públicas mexicanas están enfrentando el reto de incorporar las TIC como un recurso valioso en el proceso integral de desarrollo de habilidades, conocimientos y competencias en el alumnado. En este sentido, se presentan los resultados de un estudio cuyo objetivo fue contrastar los niveles de competencias en TIC del alumnado entre la Universidad Autónoma de Chihuahua y la Universidad Veracruzana. El criterio de selección de la muestra fue tomar una licenciatura afín sobre sistemas computacionales. El estudio fue cuantitativo y de carácter exploratorio. Se alcanzó una muestra de 240 alumnos en ambas universidades, de los cuales 134 pertenecen a la Universidad Veracruzana y 106 a la Universidad Autónoma de Chihuahua. En ambas universidades se aplicó el mismo instrumento cuantitativo. El análisis de los resultados se hizo por frecuencia y se empleó un procesamiento cuantitativo (porcentajes, frecuencias, medias, Chi cuadrado. Los resultados muestran confianza de los estudiantes en sus competencias en TIC para interactuar en ambientes de enseñanza mediados por tecnología. Además, no se encontraron diferencias significativas por género entre los niveles de competencias estudiados en ambas universidades.

  20. Activities of Native and Tyrosine-69 Mutant Phospholipases A2 on Phospholipid Analogues. A Reevaluation of the Minimal Substrate Requirements

    OpenAIRE

    Kuipers, Oscar P.; Dekker, Nicolaas; Verheij, Hubertus M.; Haas, Gerard H. de

    1990-01-01

    The role of Tyr-69 of porcine pancreatic phospholipase A2 in substrate binding was studied with the help of proteins modified by site-directed mutagenesis and phospholipid analogues with a changed head-group geometry. Two mutants were used containing Phe and Lys, respectively, at position 69. Modifications in the phospholipids included introduction of a sulfur at the phosphorus (thionophospholipids), removal of the negative charge at phosphorus (phosphatidic acid dimethyl ester), and reductio...

  1. Intracellular accumulation of potent amiloride analogues by human neutrophils

    International Nuclear Information System (INIS)

    Simchowitz, L.; Woltersdorf, O.W. Jr.; Cragoe, E.J. Jr.

    1987-01-01

    The mechanism of uptake of a series of amiloride derivatives by human neutrophils was investigated using [ 14 C]amiloride and the 14 C-labeled 5-(1-hexahydroazepinyl)-6-bromo analogue (BrMM) which is approximately 500-fold more potent than the parent compound at inhibiting Na+/H+ exchange. At an external concentration of 2 microM, the influx of BrMM at 37 degrees C was rapid, reaching a steady state by approximately 20 min. The rate of BrMM uptake (approximately 25 mumol/liter.min) was approximately 90-fold faster than for the same concentration of amiloride, a finding which correlates with differences in lipid partitioning of the two compounds. Uptake was unrelated to specific binding to Na+/H+ exchange transport sites: influx of either drug was nonsaturable whereas amiloride- and BrMM-mediated inhibition of Na+/H+ countertransport obeyed Michaelis-Menten kinetics with apparent Ki values of approximately 75 and approximately 0.2 microM. Entry occurred exclusively via the neutral (uncharged) forms (pK'a 8.40-8.55). Influx was markedly pH-dependent: it was enhanced by extracellular alkalinization and reduced by acidification. Influx was, however, insensitive to large changes in membrane voltage, thereby implying the protonated (charged) species to be impermeant. About 75% of the total intracellular pool of amiloride, but only approximately 25% of BrMM, is contained within the lysosomes, an expected consequence of the partitioning and subsequent trapping of a weak base within this strongly acidic subcellular compartment. With BrMM, there was a relative approximately 60-fold enrichment in the internal/external water concentration ratio of the drug; the value for amiloride was much less, approximately 4. This disparity is consistent with substantial binding of BrMM to internal constituents, presumably to proteins and/or nucleic acids

  2. Assessment of six dissimilarity metrics for climate analogues

    Science.gov (United States)

    Grenier, Patrick; Parent, Annie-Claude; Huard, David; Anctil, François; Chaumont, Diane

    2013-04-01

    Spatial analogue techniques consist in identifying locations whose recent-past climate is similar in some aspects to the future climate anticipated at a reference location. When identifying analogues, one key step is the quantification of the dissimilarity between two climates separated in time and space, which involves the choice of a metric. In this communication, spatial analogues and their usefulness are briefly discussed. Next, six metrics are presented (the standardized Euclidean distance, the Kolmogorov-Smirnov statistic, the nearest-neighbor distance, the Zech-Aslan energy statistic, the Friedman-Rafsky runs statistic and the Kullback-Leibler divergence), along with a set of criteria used for their assessment. The related case study involves the use of numerical simulations performed with the Canadian Regional Climate Model (CRCM-v4.2.3), from which three annual indicators (total precipitation, heating degree-days and cooling degree-days) are calculated over 30-year periods (1971-2000 and 2041-2070). Results indicate that the six metrics identify comparable analogue regions at a relatively large scale, but best analogues may differ substantially. For best analogues, it is also shown that the uncertainty stemming from the metric choice does generally not exceed that stemming from the simulation or model choice. A synthesis of the advantages and drawbacks of each metric is finally presented, in which the Zech-Aslan energy statistic stands out as the most recommended metric for analogue studies, whereas the Friedman-Rafsky runs statistic is the least recommended, based on this case study.

  3. Insulin analogues and cancer: a note of caution

    Directory of Open Access Journals (Sweden)

    Joseph A.M.J.L. eJanssen

    2014-05-01

    Full Text Available Abstract In view of the lifelong exposure and large patient populations involved, insulin analogues with an increased mitogenic effect in comparison to human insulin may potentially constitute a major health problem, since these analogues may possibly induce the growth of pre-existing neoplasms. At present, the available data suggest that insulin analogues are safe. In line with these findings, we observed that serum of diabetic patients treated with insulin analogues, compared to that of diabetic patients treated with human insulin, did not induce an increased phosphorylation of tyrosine residues of the insulin-like growth factor-I receptor (IGF-IR. However, the classical model of the IGF-IR signaling may be insufficient to explain (all mitogenic effects of insulin analogues since also non-canonical signaling pathways of the IGF-IR may play a major role in this respect. Although phosphorylation of tyrosine residues of the IGF-IR is generally considered to be the initial activation step within the intracellular IGF-IR signaling pathway, it has been found that cells undergo a signaling switch under hyperglycemic conditions. After this switch, a completely different mechanism is utilized to activate the mitogenic (mitogen-activated protein kinase (MAPK pathways of the IGF-IR that is independent from tyrosine phosphorylation of the IGF-IR. At present it is unknown whether activation of this alternative intracellular pathway of the IGF-IR occurs during hyperglycemia in vivo and whether it is stronger in patients treated with (some insulin analogues than in patients treated with human insulin. In addition, it is unknown whether the insulin receptors (IRs also undergo a signaling switch during hyperglycemia. This should be investigated in future studies. Finally, relative overexpression of IR isoform A (IR-A in (pre cancer tissues may play a key role in the development and progression of human cancers during treatment with insulin (analogues. Further

  4. MARKOV GRAPHS OF ONE–DIMENSIONAL DYNAMICAL SYSTEMS AND THEIR DISCRETE ANALOGUES AND THEIR DISCRETE ANALOGUES

    Directory of Open Access Journals (Sweden)

    SERGIY KOZERENKO

    2016-04-01

    Full Text Available One feature of the famous Sharkovsky’s theorem is that it can be proved using digraphs of a special type (the so–called Markov graphs. The most general definition assigns a Markov graph to every continuous map from the topological graph to itself. We show that this definition is too broad, i.e. every finite digraph can be viewed as a Markov graph of some one–dimensional dynamical system on a tree. We therefore consider discrete analogues of Markov graphs for vertex maps on combinatorial trees and characterize all maps on trees whose discrete Markov graphs are of the following types: complete, complete bipartite, the disjoint union of cycles, with every arc being a loop.

  5. Natural analogue studies of the role of colloids, natural organics and microorganisms on radionuclide transport

    International Nuclear Information System (INIS)

    McCarthy, J.F.

    1994-01-01

    Colloids may be important as a geochemical transport mechanism for radionuclides at geological repositories if they are (1) present in the groundwater, (2) stable with respect to both colloidal and chemical stabilities, (3) capable of adsorbing radionuclides, especially if the sorption is irreversible, and (4) mobile in the subsurface. The available evidence from natural analogue and other field studies relevant to these issues is reviewed, as is the potential role of mobile microorganisms (open-quotes biocolloidsclose quotes) on radionuclide migration. Studies have demonstrated that colloids are ubiquitous in groundwater, although colloid concentrations in deep, geochemically stable systems may be too low to affect radionuclide transport. However, even low colloid populations cannot be dismissed as a potential concern because colloids appear to be stable, and many radionuclides that adsorb to colloids are not readily desorbed over long periods. Field studies offer somewhat equivocal evidence concerning colloid mobility and cannot prove or disprove the significance of colloid transport in the far-field environment. Additional research is needed at new sites to properly represent a repository far-field. Performance assessment would benefit from natural analogue studies to examine colloid behavior at sites encompassing a suite of probable groundwater chemistries and that mimic the types of formations selected for radioactive waste repositories

  6. Fungal growth inhibitory properties of new phytosphingolipid analogues.

    Science.gov (United States)

    Mormeneo, D; Manresa, A; Casas, J; Llebaria, A; Delgado, A

    2008-04-01

    To study the growth inhibitory properties of a series of phytosphingosine (PHS) and phytoceramide (PHC) analogues. A panel of two yeast (Candida albicans and Saccharomyces cerevisiae) and six moulds (Aspergillus repens, Aspergillus niger, Penicillium chrysogenum, Cladosporium cladosporioides, Arthroderma uncinatum and Penicillium funiculosum) has been used in this study. A series of new PHS and PHC analogues differing at the sphingoid backbone and the functional group at C1 position were synthesized. Among PHS analogues, 1-azido derivative 1c, bearing the natural D-ribo stereochemistry, showed a promising growth inhibitory profile. Among PHC analogues, compound 12, with a bulky N-pivaloyl group and a Z double bond at C3 position of the sphingoid chain, was the most active growth inhibitor. Minimal inhibitory concentration values were in the range of 23-48 micromol l(-1) for 1c and 44-87 micromol l(-1) for 12. Only scattered data on the antifungal activity of phytosphingolipids have been reported in the literature. This is the first time that a series of analogues of this kind are tested and compared to discern their structural requirements for antifungal activity.

  7. On the robustness of entanglement in analogue gravity systems

    International Nuclear Information System (INIS)

    Bruschi, D E; Friis, N; Fuentes, I; Weinfurtner, S

    2013-01-01

    We investigate the possibility of generating quantum-correlated quasi-particles utilizing analogue gravity systems. The quantumness of these correlations is a key aspect of analogue gravity effects and their presence allows for a clear separation between classical and quantum analogue gravity effects. However, experiments in analogue systems, such as Bose–Einstein condensates (BECs) and shallow water waves, are always conducted at non-ideal conditions, in particular, one is dealing with dispersive media at non-zero temperatures. We analyse the influence of the initial temperature on the entanglement generation in analogue gravity phenomena. We lay out all the necessary steps to calculate the entanglement generated between quasi-particle modes and we analytically derive an upper bound on the maximal temperature at which given modes can still be entangled. We further investigate a mechanism to enhance the quantum correlations. As a particular example, we analyse the robustness of the entanglement creation against thermal noise in a sudden quench of an ideally homogeneous BEC, taking into account the super-sonic dispersion relations. (paper)

  8. Field Exploration and Life Detection Sampling for Planetary Analogue Research (FELDSPAR)

    Science.gov (United States)

    Gentry, D.; Stockton, A. M.; Amador, E. S.; Cable, M. L.; Cantrell, T.; Chaudry, N.; Cullen, T.; Duca, Z. A.; Jacobsen, M. B.; Kirby, J.; McCaig, H. C.; Murukesan, G.; Rennie, V.; Rader, E.; Schwieterman, E. W.; Stevens, A. H.; Sutton, S. A.; Tan, G.; Yin, C.; Cullen, D.; Geppert, W.

    2017-12-01

    Extraterrestrial studies are typically conducted on mg samples from cm-scale features, while landing sites are selected based on m to km-scale features. It is therefore critical to understand spatial distribution of organic molecules over scales from cm to the km, particularly in geological features that appear homogenous at m to km scales. This is addressed by FELDSPAR, a NASA-funded project that conducts field operations analogous to Mars sample return in its science, operations, and technology [1]. Here, we present recent findings from a 2016 and a 2017 campaign to multiple Martian analogue sites in Iceland. Icelandic volcanic regions are Mars analogues due to desiccation, low nutrient availability, temperature extremes [2], and are relatively young and isolated from anthropogenic contamination [3]. Operationally, many Icelandic analogue sites are remote enough to require that field expeditions address several sampling constraints that are also faced by robotic exploration [1, 2]. Four field sites were evaluated in this study. The Fimmvörðuháls lava field was formed by a basaltic effusive eruption associated with the 2010 Eyjafjallajökull eruption. Mælifellssandur is a recently deglaciated plain to the north of the Myrdalsjökull glacier. Holuhraun is a basaltic spatter and cinder cone formed by 2014 fissure eruptions just north of the Vatnajökull glacier. Dyngjusandur is a plain kept barren by repeated aeolian mechanical weathering. Samples were collected in nested triangular grids from 10 cm to the 1 km scale. We obtained overhead imagery at 1 m to 200 m elevation to create digital elevation models. In-field reflectance spectroscopy was obtained with an ASD spectrometer and chemical composition was measured by a Bruker handheld XRF. All sites chosen were homogeneous in apparent color, morphology, moisture, grain size, and reflectance spectra at all scales greater than 10 cm. Field lab ATP assays were conducted to monitor microbial habitation, and home

  9. Numerical analysis of a proposed percolation experiment at the Pena Blanca natural analog site

    International Nuclear Information System (INIS)

    Green, R.T.; Rice, G.

    1995-01-01

    A field-scale percolation test is proposed for the Pena Blanca natural analog site near Chihuahua, MX. To aid in design of the field test, the V-TOUGH two-phase flow simulator was applied to model percolation of water through 8 to 10 m of partially saturated fractured tuff. The rock was characterized as a composite medium using measured hydraulic properties for the rock matrix and estimated values for the fractures. Measured matrix permeability varied over four orders of magnitude and fracture apertures were estimated to range from 10 to 1,000 μm. Water arrival times were predicted to vary between one day to 10,000 yr. The utility of the composite model and other representations of flow through fractured porous media can be tested using results from the field scale infiltration test data

  10. Paired Magmatic-Metallogenic Belts in Myanmar - an Andean Analogue?

    Science.gov (United States)

    Gardiner, Nicholas; Robb, Laurence; Searle, Michael; Morley, Christopher

    2015-04-01

    contrasting minerals endowment. The Mogok-Mandalay-Mergui (MMM) Belt hosts crustal-melt S-type granites with significant tin-tungsten mineralization, and contains the historically major tungsten deposit of Mawchi. The Wuntho-Popa Arc comprises I-type granites and granodiorites with porphyry-type copper-gold and epithermal gold mineralization, and includes the world-class Monywa copper mine. Recent U-Pb radiometric age dating has shown the potential for the two belts to be both active from the Late Cretaceous to Eocene. The spatial juxtaposition of these two sub-parallel belts, the implication of contemporary magmatism, and their distinct but consistent metallogenic endowment bears strong similarities to the metallogenic belts of the South American Cordillera. Here we investigate whether they together represent the magmatic and metallogenic expression of an Andean-type setting in Myanmar during the subduction of Neo-Tethys. In this analogue the Wuntho-Popa Arc represents a proximal I-type magmatic belt sited immediately above the eastwards-verging Neo-Tethys subduction zone. Exhibiting porphyry-type copper-gold and epithermal gold mineralization, this would therefore be the Myanmar equivalent of the Andean coastal copper belts. Conversely, the parallel MMM Belt, comprised of more distal crustal-melt S-type tin granites, would have an analogue in the Bolivian tin belt.

  11. Calculation of the structural shielding of the radiotherapy treatment room equipped with a linear accelerator type Tomo therapy Hi-Art in the Oncology Center of Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Caballero G, C. A.; Plascencia, J. C.; Vargas V, M. X.; Toledo J, P.

    2010-09-01

    . In this work these specific methodologies are used for the structural shielding calculations of the tomo therapy equipment installed in the Oncology Center of Chihuahua. These calculation methodologies consider the primary radiation, of leakage, disperse, second dispersion and leakage dispersion. The obtained results indicate that due to the lead barrier of the primary beam, the main component that contributes to the shielding requirements of the installation is the leakage radiation. On the other hand, the component that more affects of the door shielding is the dispersion component in the patient. (Author)

  12. A geologic and geophysic study of the Sierra de Pena Blanca, in the state of Chihuahua, Mexico

    International Nuclear Information System (INIS)

    Lopez S, F.A.

    1976-01-01

    Within the sistematic aerial exploration program realized by the Instituto Nacional de Energia Nuclear, an aeroradiometric study was carried out in the zone which includes Sierra de Pena Blanca. This study took into consideration the former and present geological investigations and compromised the sierra together with the bordering valleys. The main objective consists in the localization of areas presenting favorable conditions for the existence of uranium isotopes minerlization, in order to determine a mineralized body or ore deposit. For that purpose the area was explored with an airplane to which a differential gamma rays spectrometer was adapted, this spectrometer will show us clearly the integration of the number of radiations which fall into the detectors obtaining this way a valuable information about the radiometric anomalous sites of the studied zone and also about the existence of bismuth, thallium and the abundant potassium of the igneous rocks. These anomalies are under the stage of ground verification, this stage includes a superficial study and the study of the underlying rocks through drilling, radiometric logs and chemical analysis of the samples. In fact, through this method we can obtain very truthful data. (author)

  13. Radiation-Driven Formation of Reactive Oxygen Species in Oxychlorine-Containing Mars Surface Analogues

    Science.gov (United States)

    Georgiou, Christos D.; Zisimopoulos, Dimitrios; Kalaitzopoulou, Electra; Quinn, Richard C.

    2017-04-01

    The present study demonstrates that γ-radiolyzed perchlorate-containing Mars soil salt analogues (in a CO2 atmosphere) generate upon H2O wetting the reactive oxygen species (ROS) superoxide radical (O2•-), hydrogen peroxide (H2O2), and hydroxyl radicals (•OH). This study also validates that analogue radiolysis forms oxychlorine species that, in turn, can UV-photolyze to •OH upon UV photolysis. This investigation was made possible by the development of a new assay for inorganic-origin O2•- and H2O2 determination and by the modification of a previous assay for soil •OH. Results show that radiolyzed Mg(ClO4)2 generates H2O2 and •OH; and when included as part of a mixture analogous to the salt composition of samples analyzed at the Mars Phoenix site, the analogue generated O2•-, H2O2, and •OH, with •OH levels 150-fold higher than in the radiolyzed Mg(ClO4)2 samples. Radiolyzed Mars Phoenix site salt analogue that did not contain Mg(ClO4)2 generated only •OH also at 150-fold higher concentration than Mg(ClO4)2 alone. Additionally, UV photolysis of the perchlorate γ radiolysis product chlorite (ClO2-) generated the oxychlorine products trihalide (Cl3-), chlorine dioxide (ClO2•), and hypochlorite (ClO-), with the formation of •OH by UV photolysis of ClO-. While the generation of ROS may have contributed in part to 14CO2 production in the Viking Labeled Release (LR) experiment and O2 (g) release in the Viking Gas Exchange (GEx) experiment, our results indicate that they are not likely to be the major contributor to the LR and GEx results. However, due to their highly reactive nature, they are expected to play a significant role in the alteration of organics on Mars. Additionally, experiments with hypochlorite show that the thermal stability of NaClO is in the range of the thermal stability observed for thermally liable oxidant responsible for the Viking LR results.

  14. Analogues to features and processes of a high-level radioactive waste repository proposed for Yucca Mountain, Nevada

    Science.gov (United States)

    Simmons, Ardyth M.; Stuckless, John S.; with a Foreword by Abraham Van Luik, U.S. Department of Energy

    2010-01-01

    Natural analogues are defined for this report as naturally occurring or anthropogenic systems in which processes similar to those expected to occur in a nuclear waste repository are thought to have taken place over time periods of decades to millennia and on spatial scales as much as tens of kilometers. Analogues provide an important temporal and spatial dimension that cannot be tested by laboratory or field-scale experiments. Analogues provide one of the multiple lines of evidence intended to increase confidence in the safe geologic disposal of high-level radioactive waste. Although the work in this report was completed specifically for Yucca Mountain, Nevada, as the proposed geologic repository for high-level radioactive waste under the U.S. Nuclear Waste Policy Act, the applicability of the science, analyses, and interpretations is not limited to a specific site. Natural and anthropogenic analogues have provided and can continue to provide value in understanding features and processes of importance across a wide variety of topics in addressing the challenges of geologic isolation of radioactive waste and also as a contribution to scientific investigations unrelated to waste disposal. Isolation of radioactive waste at a mined geologic repository would be through a combination of natural features and engineered barriers. In this report we examine analogues to many of the various components of the Yucca Mountain system, including the preservation of materials in unsaturated environments, flow of water through unsaturated volcanic tuff, seepage into repository drifts, repository drift stability, stability and alteration of waste forms and components of the engineered barrier system, and transport of radionuclides through unsaturated and saturated rock zones.

  15. Martian Feeling: An Analogue Study to Simulate a Round-Trip to Mars using the International Space Station

    Science.gov (United States)

    Felix, C. V.; Gini, A.

    When talking about human space exploration, Mars missions are always present. It is clear that sooner or later, humanity will take this adventure. Arguably the most important aspect to consider for the success of such an endeavour is the human element. The safety of the crew throughout a Martian mission is a top priority for all space agencies. Therefore, such a mission should not take place until all the risks have been fully understood and mitigated. A mission to Mars presents unique human and technological challenges in terms of isolation, confinement, autonomy, reliance on mission control, communication delays and adaptation to different gravity levels. Analogue environments provide the safest way to simulate these conditions, mitigate the risks and evaluate the effects of long-term space travel on the crew. Martian Feeling is one of nine analogue studies, from the Mars Analogue Path (MAP) report [1], proposed by the TP Analogue group of ISU Masters class 2010. It is an integrated analogue study which simulates the psychological, physiological and operational conditions that an international, six-person, mixed gender crew would experience on a mission to Mars. Set both onboard the International Space Station (ISS) and on Earth, the Martian Feeling study will perform a ``dress rehearsal'' of a mission to Mars. The study proposes to test both human performance and operational procedures in a cost-effective manner. Since Low Earth Orbit (LEO) is more accessible than other space-based locations, an analogue studies in LEO would provide the required level of realism to a simulated transit mission to Mars. The sustained presence of microgravity and other elements of true spaceflight are features of LEO that are neither currently feasible nor possible to study in terrestrial analogue sites. International collaboration, economics, legal and ethical issues were considered when the study was proposed. As an example of international collaboration, the ISS would

  16. Alligator Rivers Analogue project. Geochemical Data Bases

    International Nuclear Information System (INIS)

    Bennett, D.G.; Read, D.

    1992-01-01

    The Koongarra uranium deposit in the Northern Territory of Australia is being studied to evaluate the processes involved in the geochemical alteration of the ore body and the formation of the uranium dispersion fan. A broad range of research is being undertaken into the geochemistry and hydrology of the site with the aim of understanding the transport of radionuclides through the system. During the project a range of geochemical and hydrogeochemical models have been developed to account for measured data from the site and with which to predict site evolution. The majority of these models are based on the premise of thermodynamic chemical equilibrium and employ fundamental thermodynamic data to characterise the chemistry of the system. From the differences which exist between the thermodynamic data bases (Appendices I and II) it is possible to gain a view of the level of uncertainty associated with thermodynamic data in each set of calculations. This report gives a brief introduction to the geochemical processes underlying the models, and details the equations used to quantify the more common of these processes (e.g. aqueous speciation and mineral solubility). A description is given of the computer codes (EQ3/6, PHREEQE, MINTEQ) most commonly used during the project for geochemical modelling. Their key features are highlighted and comparisons made. It is concluded that the degree of uncertainty in geochemical modelling studies arising as a result of using one code rather than another is relatively insignificant when compared to that related to differences in the underlying data bases. 73 refs., 3 figs

  17. Concise synthesis of new bridged-nicotine analogues

    DEFF Research Database (Denmark)

    Crestey, François; Hooyberghs, Geert; Kristensen, Jesper Langgaard

    2012-01-01

    This study describes a very efficient strategy for the synthesis of two new bridged-nicotine analogues. Starting from either 4- or 3-chloropyridine the desired tricyclic ring systems are accessed in just three steps in 23% and 40% overall yield, respectively.......This study describes a very efficient strategy for the synthesis of two new bridged-nicotine analogues. Starting from either 4- or 3-chloropyridine the desired tricyclic ring systems are accessed in just three steps in 23% and 40% overall yield, respectively....

  18. Naturally occurring crystalline phases: analogues for radioactive waste forms

    International Nuclear Information System (INIS)

    Haaker, R.F.; Ewing, R.C.

    1981-01-01

    Naturally occurring mineral analogues to crystalline phases that are constituents of crystalline radioactive waste forms provide a basis for comparison by which the long-term stability of these phases may be estimated. The crystal structures and the crystal chemistry of the following natural analogues are presented: baddeleyite, hematite, nepheline; pollucite, scheelite;sodalite, spinel, apatite, monazite, uraninite, hollandite-priderite, perovskite, and zirconolite. For each phase in geochemistry, occurrence, alteration and radiation effects are described. A selected bibliography for each phase is included

  19. Analogues of luteinizing hormone-releasing hormone containing cytotoxic groups.

    Science.gov (United States)

    Janáky, T; Juhász, A; Bajusz, S; Csernus, V; Srkalovic, G; Bokser, L; Milovanovic, S; Redding, T W; Rékási, Z; Nagy, A

    1992-02-01

    In an attempt to produce better cytotoxic analogues, chemotherapeutic antineoplastic radicals including an alkylating nitrogen mustard derivative of D-phenylalanine (D-melphalan), reactive cyclopropane, anthraquinone derivatives [2-(hydroxymethyl)anthraquinone and the anticancer antibiotic doxorubicin], and an antimetabolite (methotrexate) were coupled to suitably modified agonists and antagonists of luteinizing hormone-releasing hormone (LH-RH). Analogues with D-lysine6 and D-ornithine6 or N epsilon-(2,3-diaminopropionyl)-D-lysine and N delta-(2,3-diaminopropionyl)-D-ornithine were used as carriers for one or two cytotoxic moieties. The enhanced biological activities produced by the incorporation of D amino acids into position 6 of the agonistic analogues were further increased by the attachment of hydrophobic cytotoxic groups, resulting in compounds with 10-50 times higher activity than LH-RH. Most of the monosubstituted agonistic analogues showed high affinities for the membrane receptors of human breast cancer cells, while the receptor binding affinities of peptides containing two cytotoxic side chains were lower. Antagonistic carriers [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Trp3,Arg5,D-Lys6,D-Ala10] LH-RH [where Nal(2) is 3-(2-naphthyl)alanine], [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Trp3,Arg5,N epsilon-(2,3-diaminopropionyl)-D-Lys6,D-Ala10]LH-RH, and their D-Pal(3)3 homologs [Pal(3) is 3-(3-pyridyl)alanine] as well as [Ac-D-Nal(2)1,D-Phe(4Cl)2,D-Pal(3)3,Tyr5,N epsilon-(2,3-diamino-propionyl)-D-Lys6,D-Ala10]LH-RH were linked to cytotoxic compounds. The hybrid molecules inhibited ovulation in rats at doses of 10 micrograms and suppressed LH release in vitro. The receptor binding of cytotoxic analogues was decreased compared to the precursor peptides, although analogues with 2-(hydroxymethyl)anthraquinone hemiglutarate had high affinities. All of the cytotoxic analogues tested inhibited [3H]thymidine incorporation into DNA in cultures of human breast and prostate cancer cell lines

  20. A Low-cost Multi-channel Analogue Signal Generator

    CERN Document Server

    Muller, F; Shen, W; Stamen, R

    2009-01-01

    A scalable multi-channel analogue signal generator is presented. It uses a commercial low-cost graphics card with multiple outputs in a standard PC as signal source. Each color signal serves as independent channel to generate an analogue signal. A custom-built external PCB was developed to adjust the graphics card output voltage levels for a specific task, which needed differential signals. The system furthermore comprises a software package to program the signal shape. The implementation of the signal generator is presented as well as an application where it was successfully utilized.

  1. Design of a saturated analogue and digital current transducer

    International Nuclear Information System (INIS)

    Pross, Alexander

    2002-01-01

    This project describes the development of a new analogue and digital current transducer, providing a range of new theoretical design methods for these novel devices. The main control feature is the limit cycling operation, and the novel use of the embedded sigma-delta modulator sensor structure to derive a low component count digital sensor. The research programme was initiated into the design, development and evaluation of a novel non-Hall sensing analogue and digital current transducer. These transducers are used for measurement of high currents in power systems applications. The investigation is concerned with a new design which uses a magnetic ferrite core without an air gap for current measurement. The motivation for this work was to design a new control circuit which provides a low component count, and utilises the non-linear properties of the magnetic ferrite core to transmit direct current. The use of a limit cycle control circuit was believed to be particularly suitable for the analogue and digital transducers, for two main reasons: the low component count, and the output signal is directly digital. In line with the motivations outlined above, the outcome of the research has witnessed the design, development and evaluation of a practically realisable analogue and digital current transducer. The design procedure, which is documented in this thesis, is considered to be a major contribution to the field of transducers design and development using a control systems approach. Mathematical models for both analogue and digital transducers were developed and the resulting model based predictions were found to be in good agreement with measured results. Simplification of the new model sensing device was achieved by approximating the non-linear ferrite core using FFT analysis. This is also considered to be a significant contribution. The development analogue and digital current censors employed a sampled data control systems design and utilised limit cycling

  2. Naturally occurring crystalline phases: analogues for radioactive waste forms

    Energy Technology Data Exchange (ETDEWEB)

    Haaker, R.F.; Ewing, R.C.

    1981-01-01

    Naturally occurring mineral analogues to crystalline phases that are constituents of crystalline radioactive waste forms provide a basis for comparison by which the long-term stability of these phases may be estimated. The crystal structures and the crystal chemistry of the following natural analogues are presented: baddeleyite, hematite, nepheline; pollucite, scheelite;sodalite, spinel, apatite, monazite, uraninite, hollandite-priderite, perovskite, and zirconolite. For each phase in geochemistry, occurrence, alteration and radiation effects are described. A selected bibliography for each phase is included.

  3. Neurochemical binding profiles of novel indole and benzofuran MDMA analogues.

    OpenAIRE

    Shimshoni, JA; Winkler, I; Golan, E; Nutt, D

    2016-01-01

    3,4-Methylenedioxy-N-methylamphetamine (MDMA) has been shown to be effective in the treatment of post-traumatic stress disorder (PTSD) in numerous clinical trials. In the present study, we have characterized the neurochemical binding profiles of three MDMA-benzofuran analogues (1-(benzofuran-5-yl)-propan-2-amine, 5-APB; 1-(benzofuran-6-yl)-N-methylpropan-2-amine, 6-MAPB; 1-(benzofuran-5-yl)-N-methylpropan-2-amine, 5-MAPB) and one MDMA-indole analogue (1-(1H-indol-5-yl)-2-methylamino-propan-1-...

  4. Optimization of gefitinib analogues with potent anticancer activity.

    Science.gov (United States)

    Yin, Kai-Hao; Hsieh, Yi-Han; Sulake, Rohidas S; Wang, Su-Pei; Chao, Jui-I; Chen, Chinpiao

    2014-11-15

    The interactions of gefitinib (Iressa) in EGFR are hydrogen bonding and van der Waals forces through quinazoline and aniline rings. However the morpholino group of gefitinib is poorly ordered due to its weak electron density. A series of novel piperazino analogues of gefitinib where morpholino group substituted with various piperazino groups were designed and synthesized. Most of them indicated significant anti-cancer activities against human cancer cell lines. In particular, compounds 52-54 showed excellent potency against cancer cells. Convergent synthetic approach has been developed for the synthesis of gefitinib intermediate which can lead to gefitinib as well as numerous analogues. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Analogue studies at the french atomic commission (CEA)

    International Nuclear Information System (INIS)

    Petit, J.C.

    1986-06-01

    The different research activities of the French Atomic Energy Commission in the analogue study field are presented. Most of them are conducted in collaboration with major research organisations, both french and international. In fact, the scientific community has been associated to these programmes at different steps of their realisation. The brief description presented illustrates the great diversity and complementarity of actions conducted by CEA for better understanding, through the study of natural analogues, the basic processes that will rule the long term behaviour of high level radwaste materials in a repository and hence contributing to hopefully guaranty disposal safety

  6. Niveles de contaminación del agua potable en la cabecera municipal de Ascención, Chihuahua, México

    Directory of Open Access Journals (Sweden)

    Héctor Osbaldo Rubio Arias

    2015-01-01

    Full Text Available Introducción: El agua es una sustancia indispensable para la vida por lo que se considera como el recurso natural más apreciado en el planeta. En el norte de México existe el “Programa ambiental México-Estados Unidos: Frontera 2020”; en el cual participan instituciones mexicanas como la Junta Municipal de Aguas y Saneamiento (JMAS mientras que por parte de los Estados Unidos de Norteamérica participan el Taskforce U.S., la Agencia Ambiental (USEPA y la Universidad Estatal de Nuevo Mexico, entre otras (PAMEUF, 2013. En dicho programa ambiental el municipio de Ascensión está contemplado dentro de los planes de acción, por ser una región fronteriza, en especial en lo relacionado a la meta 2, la cual especifica el suministro de agua limpia y segura. Es importante mencionar que, a la fecha, no se conoce información que permita evaluar el nivel de calidad que aportan los cinco pozos que surten de agua a la cabecera municipal de Ascención, Chihuahua. El objetivo fue evaluar la calidad del agua potable que utiliza la comunidad de Ascensión, Chihuahua, mediante análisis físico-químico-metales y microbiológicos. Método: Las muestras de agua se obtuvieron de cinco pozos y de cinco hogares seleccionados al azar en cuatro temporadas. Se realizaron cuatro muestreos; julio de 2011, septiembre de 2011, diciembre de 2011 y mayo de 2012. Por lo tanto, se analizaron un total de 40 muestras a las que se les cuantificó el potencial de hidrógeno (pH, conductividad eléctrica (CE, temperatura (T, oxígeno disuelto (OD, turbidez (Tur, sólidos totales (SDT, coliformes totales (CT, coliformes fecales (CF y los siguientes metales; Al, As, B, Cd, Ca, Cu, Cr, Fe, Mg, Mn, Ni, Ag, Pb, K, Na, Se, Si y Zn. Se aplicó un ANOVA para buscar diferencias por estación (Factor A, por fuente (Factor B y su interacción (AxB. Para la variable de coliformes se aplicó la prueba noparamétrica de Kruskal-Wallis. En todos los casos se consideró un nivel de

  7. Climatic Forecasting of Net Infiltration at Yucca Mountain Using Analogue Meteorological Data

    International Nuclear Information System (INIS)

    B. Faybishenko

    2006-01-01

    At Yucca Mountain, Nevada, future changes in climatic conditions will most likely alter net infiltration, or the drainage below the bottom of the evapotranspiration zone within the soil profile or flow across the interface between soil and the densely welded part of the Tiva Canyon Tuff. The objectives of this paper are to: (a) develop a semi-empirical model and forecast average net infiltration rates, using the limited meteorological data from analogue meteorological stations, for interglacial (present day), and future monsoon, glacial transition, and glacial climates over the Yucca Mountain region, and (b) corroborate the computed net-infiltration rates by comparing them with the empirically and numerically determined groundwater recharge and percolation rates through the unsaturated zone from published data. In this paper, the author presents an approach for calculations of net infiltration, aridity, and precipitation-effectiveness indices, using a modified Budyko's water-balance model, with reference-surface potential evapotranspiration determined from the radiation-based Penman (1948) formula. Results of calculations show that net infiltration rates are expected to generally increase from the present-day climate to monsoon climate, to glacial transition climate, and then to the glacial climate. The forecasting results indicate the overlap between the ranges of net infiltration for different climates. For example, the mean glacial net-infiltration rate corresponds to the upper-bound glacial transition net infiltration, and the lower-bound glacial net infiltration corresponds to the glacial transition mean net infiltration. Forecasting of net infiltration for different climate states is subject to numerous uncertainties-associated with selecting climate analogue sites, using relatively short analogue meteorological records, neglecting the effects of vegetation and surface runoff and runon on a local scale, as well as possible anthropogenic climate changes

  8. A differential scanning calorimetric study of the effects of metal ions, substrate/product, substrate analogues and chaotropic anions on the thermal denaturation of yeast enolase 1.

    Science.gov (United States)

    Brewer, J M; Wampler, J E

    2001-03-14

    The thermal denaturation of yeast enolase 1 was studied by differential scanning calorimetry (DSC) under conditions of subunit association/dissociation, enzymatic activity or substrate binding without turnover and substrate analogue binding. Subunit association stabilizes the enzyme, that is, the enzyme dissociates before denaturing. The conformational change produced by conformational metal ion binding increases thermal stability by reducing subunit dissociation. 'Substrate' or analogue binding additionally stabilizes the enzyme, irrespective of whether turnover is occurring, perhaps in part by the same mechanism. More strongly bound metal ions also stabilize the enzyme more, which we interpret as consistent with metal ion loss before denaturation, though possibly the denaturation pathway is different in the absence of metal ion. We suggest that some of the stabilization by 'substrate' and analogue binding is owing to the closure of moveable polypeptide loops about the active site, producing a more 'closed' and hence thermostable conformation.

  9. Alligator Rivers Analogue project. Hydrogeological modelling. Final Report - Volume 6

    International Nuclear Information System (INIS)

    Townley, L.R.; Trefry, M.G.; Barr, A.D.; Braumiller, S.

    1992-01-01

    This volume describes hydrogeological modelling carried out as part of the Alligator Rivers Analogue Project. Hydrogeology has played a key integrating role in the Project, largely because water movement is believed to have controlled the evolution of the Koongarra uranium Orebody and therefore affects field observations of all types at all scales. Aquifer testing described uses the concept of transmissivity in its interpretation of aquifer response to pumping. The concept of an aquifer, a layer transmitting significant quantities of water in a mainly horizontal direction, seems hard to accept in an environment as heterogeneous as that at Koongarra. But modelling of aquifers both in one dimension and two dimensionally in plan has contributed significantly to our understanding of the site. A one-dimensional model with three layers (often described as a quasi two dimensional model) was applied to flow between the Fault and Koongarra Creek. Being a transient model, this model was able to show that reverse flows can indeed occur back towards the Fault, but only if there is distributed recharge over the orebody as well as a mechanism for the Fault, or a region near the Fault, to remove water from the simulated cross-section. The model also showed clearly that the response of the three-layered system, consisting of a highly weathered zone, a fractured transmissive zone and a less conductive lower schist zone, is governed mainly by the transmissivity and storage coefficient of the middle layer. The storage coefficient of the higher layer has little effect. A two-dimensional model in plan used a description of anisotropy to show that reverse flows can also occur even without a conducting Fault. Modelling of a three-dimensional region using discrete fractures showed that it is certainly possible to simulate systems like that observed at Koongarra, but that large amounts of data are probably needed to obtain realistic descriptions of the fracture networks. Inverse modelling

  10. Alligator Rivers Analogue project. Hydrogeological modelling. Final Report - Volume 6

    Energy Technology Data Exchange (ETDEWEB)

    Townley, L R; Trefry, M G; Barr, A D [CSIRO Div of Water Resources, PO Wembley, WA (Australia); Braumiller, S [Univ of Arizona, Tucson, AZ (United States). Dept of Hydrology and Water Resources; Kawanishi, M [Central Research Institute of Electric Power Industry, Abiko-Shi, Chiba-Ken (Japan); and others

    1993-12-31

    This volume describes hydrogeological modelling carried out as part of the Alligator Rivers Analogue Project. Hydrogeology has played a key integrating role in the Project, largely because water movement is believed to have controlled the evolution of the Koongarra uranium Orebody and therefore affects field observations of all types at all scales. Aquifer testing described uses the concept of transmissivity in its interpretation of aquifer response to pumping. The concept of an aquifer, a layer transmitting significant quantities of water in a mainly horizontal direction, seems hard to accept in an environment as heterogeneous as that at Koongarra. But modelling of aquifers both in one dimension and two dimensionally in plan has contributed significantly to our understanding of the site. A one-dimensional model with three layers (often described as a quasi two dimensional model) was applied to flow between the Fault and Koongarra Creek. Being a transient model, this model was able to show that reverse flows can indeed occur back towards the Fault, but only if there is distributed recharge over the orebody as well as a mechanism for the Fault, or a region near the Fault, to remove water from the simulated cross-section. The model also showed clearly that the response of the three-layered system, consisting of a highly weathered zone, a fractured transmissive zone and a less conductive lower schist zone, is governed mainly by the transmissivity and storage coefficient of the middle layer. The storage coefficient of the higher layer has little effect. A two-dimensional model in plan used a description of anisotropy to show that reverse flows can also occur even without a conducting Fault. Modelling of a three-dimensional region using discrete fractures showed that it is certainly possible to simulate systems like that observed at Koongarra, but that large amounts of data are probably needed to obtain realistic descriptions of the fracture networks. Inverse modelling

  11. Evaluation of the antibacterial spectrum of drosocin analogues

    NARCIS (Netherlands)

    Bikker, F.J.; Kaman-van Zanten, W.E.; Vries-van de Ruit, A.M.B.C. de; Voskamp-Visser, I.; Hooft, P.A.V. van; Mars-Groenendijk, R.H.; Visser, P.C. de; Noort, D.

    2006-01-01

    Drosocin is a 19-mer, cationic antimicrobial peptide from Drosophila melanogaster. The aim of the study was to examine the antibacterial spectrum of unglycosylated drosocin analogues. Furthermore, the amino acid sequence of DnaK, drosocin's intracellular target, from susceptible species was aligned

  12. Trehalose Analogues: Latest Insights in Properties and Biocatalytic Production

    Directory of Open Access Journals (Sweden)

    Maarten Walmagh

    2015-06-01

    Full Text Available Trehalose (α-d-glucopyranosyl α-d-glucopyranoside is a non-reducing sugar with unique stabilizing properties due to its symmetrical, low energy structure consisting of two 1,1-anomerically bound glucose moieties. Many applications of this beneficial sugar have been reported in the novel food (nutricals, medical, pharmaceutical and cosmetic industries. Trehalose analogues, like lactotrehalose (α-d-glucopyranosyl α-d-galactopyranoside or galactotrehalose (α-d-galactopyranosyl α-d-galactopyranoside, offer similar benefits as trehalose, but show additional features such as prebiotic or low-calorie sweetener due to their resistance against hydrolysis during digestion. Unfortunately, large-scale chemical production processes for trehalose analogues are not readily available at the moment due to the lack of efficient synthesis methods. Most of the procedures reported in literature suffer from low yields, elevated costs and are far from environmentally friendly. “Greener” alternatives found in the biocatalysis field, including galactosidases, trehalose phosphorylases and TreT-type trehalose synthases are suggested as primary candidates for trehalose analogue production instead. Significant progress has been made in the last decade to turn these into highly efficient biocatalysts and to broaden the variety of useful donor and acceptor sugars. In this review, we aim to provide an overview of the latest insights and future perspectives in trehalose analogue chemistry, applications and production pathways with emphasis on biocatalysis.

  13. Combinatorial Solid-Phase Synthesis of Balanol Analogues

    DEFF Research Database (Denmark)

    Nielsen, John; Lyngsø, Lars Ole

    1996-01-01

    The natural product balanol has served as a template for the design and synthesis of a combinatorial library using solid-phase chemistry. Using a retrosynthetic analysis, the structural analogues have been assembled from three relatively accessible building blocks. The solid-phase chemistry inclu...

  14. A Short Review on Cardiotonic Steroids and Their Aminoguanidine Analogues

    Directory of Open Access Journals (Sweden)

    Arturo San Feliciano

    2000-01-01

    Full Text Available A short review on cardiotonic steroids and their analogues is presented. The natural, semisynthetic and synthetic derivatives, as well as their mechanism of action and structure-activity relationships are shown, with a special reference to aminoguanidine derivatives.

  15. Synthesis and biological evaluation of novel gramicidin s analogues

    NARCIS (Netherlands)

    Tuin, A.W.; Palachanis, D.K.; Buizert, A.; Grotenbreg, G.M.; Spalburg, E.; Neeling, A.J. de; Mars-Groenendijk, R.H.; Noort, D.; Marel, G.A. van der; Overkleeft, H.S.; Overhand, M.

    2009-01-01

    The synthesis of three new analogues of the cyclic cationic antimicrobial peptide Gramicidin S is described. These derivatives contain a modified turn region in which the DPhe-Pro motif has been replaced by a constrained furanoid sugar amino acid or a flexible linear aminoethoxy acetic acid moiety.

  16. A new analogue of fatty alcohol from Tamarix hampeana L.

    Science.gov (United States)

    Aykac, Ahmet; Akgül, Yurdanur

    2010-01-01

    New analogues of a long-chain secondary alcohol (1) and laserine (2) were isolated from the flowers of Tamarix hampeana L. The isolated compounds were identified using 1D and 2D NMR, LCMS/APCI, and chemical methods. Laserine was isolated for the first time from T. hampeana L.

  17. An Analysis of an Autoclitic Analogue in Pigeons

    Science.gov (United States)

    Kuroda, Toshikazu; Lattal, Kennon A.; García-Penagos, Andrés

    2014-01-01

    Using a conditional discrimination procedure, pigeons were exposed to a nonverbal analogue of qualifying autoclitics such as "definitely" and "maybe." It has been suggested that these autoclitics are similar to tacts except that they are under the control of private discriminative stimuli. Instead of the conventional assumption…

  18. Difference in brain activations during appreciating paintings and photographic analogues

    Directory of Open Access Journals (Sweden)

    Yoshinori eMizokami

    2014-07-01

    Full Text Available Several studies have investigated neural correlates of aesthetic appreciation for paintings but to date the findings have been heterogeneous. This heterogeneity may be attributed to previous studies’ measurement of aesthetic appreciation of not only the beauty of paintings but also the beauty of motifs of the paintings. In order to better elucidate the beauty of paintings, it seems necessary to compare aesthetic appreciation of paintings and photographic analogues which included corresponding real images. We prepared for famous painters’ pictures and their photographic analogues which were set up to resemble each painting in order to investigate the hypothesis that there exist specific neural correlates associated with the aesthetic appreciation for paintings. Forty-four subjects participated in functional magnetic resonance study which required comparisons of aesthetic appreciation of paintings of still life and landscape versus photographic analogues including corresponding real images of still life and landscape. Bilateral cuneus and the left lingual gyrus were activated in the comparison of aesthetic appreciation of paintings versus photographic analogues. In conclusion, the present findings suggest a possibility of the existence of specific neural correlates associated with the aesthetic appreciation for paintings and that bilateral cuneus and the left lingual gyrus may be involved.

  19. BlockLevel Bayesian Diagnosis of Analogue Electronic Circuits

    NARCIS (Netherlands)

    Krishnan, Shaji; Krishnan, Shaji; Kerkhoff, Hans G.; Doornbosch, Klaas D.; Brand, Rudi

    2010-01-01

    Daily experience with product designers, test and diagnosis engineers it is realized that the depth of interaction among them, ought to be high for successful diagnosis of analogue circuits. With this knowledge in mind, a responsibility was undertaken to choose a popular diagnostic method and define

  20. An azumamide C analogue without the zinc-binding functionality

    DEFF Research Database (Denmark)

    Villadsen, Jesper; Kitir, Betül; Wich, Kathrine

    2014-01-01

    + - coordinating moiety. Herein, we describe the synthesis of an azumamide analogue lacking its native Zn 2+ -binding group and evaluation of its inhibitory activity against recombinant human HDAC1 – 11. Furthermore, kinetic investigation of the inhibitory mechanism of both parent natural product and synthetic...

  1. Reasoning by analogy: rational foundation of natural analogue studies

    International Nuclear Information System (INIS)

    Petit, J.-C.

    1992-01-01

    Long-term extrapolations concerning the safety of a nuclear waste repository cannot be satisfactorily made on the sole basis of short-term laboratory investigations. Most nuclear countries have hence developed an approach relying on the following research directions: 1. laboratory experiments; 2. in situ testing; 3. modeling; and 4. natural analogues, which are the only means by which very slow mechanisms can be identified and by which long-term predictions of models can be tested for pertinence (if not truly validated). Although the field of natural analogues has grown very rapidly in recent years, receiving support from varied specialists and institutions involved in radioactive waste disposal, there is not yet a full consensus on their actual usefulness. More problematic is the criticism sometimes made that analogical reasoning is not ''true science'' and that information retrieved from the study of natural analogues will always remain questionable. The present paper gives some clues about the exact status of reasoning by analogy, compared to more ''scientific'' ways of deriving information from investigated systems. It is not a thorough discussion of this very complex, and by far too philosophical issue but we hope, at least, to present to readers of papers devoted to natural analogue studies arguments showing that this approach has some sound foundation. (author)

  2. Analogues of estradiol as potential breast tumor imaging agents

    International Nuclear Information System (INIS)

    Gibson, R.E.; Rzeszotarski, W.J.; Ferriera, N.L.; Jagoda, E.M.; Reba, R.C.; Eckelman, W.C.

    1984-01-01

    The radioiodinated analogue of estradiol, 11β-methoxy-17α-[/sup 125/I]iodovinylestradiol (MIVE/sub 2/), has been shown to be a good candidate for the imaging of estrogen dependent breast tumors. Although there has been no extensive study on the sensitivity of radiotracers of this type, the authors have not observed localization of the radiotracer in metastatic lesions containing less than 20 fmole estrogen receptor/mg protein or in bone metasteses. In order to improve the sensitivity, they have examined several structural analogues of moxestrol (the parent structure for MIVE/sub 2/) for affinity to the ER isolated from immature rat uterus. The 11β-ethyl analogue (EEE/sub 2/) of ethynyl estradiol (EE/sub 2/) exhibits the highest affinity with the 11β-methyl analogue second best. Although the lipophilicity is also very high this compound should not be much more lipophilic than 16-iodoestradiol or MIVE/sub 2/ since the introduction of iodine increases the log P by greater than 1. The distribution of the tritiated derivative of EEE/sub 2/ is under study

  3. Block-level Bayesian diagnosis of analogue electronic circuits

    NARCIS (Netherlands)

    Krishnan, S.; Doornbos, K.D.; Brand, R.; Kerkhoff, H.G.

    2010-01-01

    Daily experience with product designers, test and diagnosis engineers it is realized that the depth of interaction among them, ought be high for sucessfull diagnosis of analogue circuits. With this knowledge in mind, a responsibility was undertaken to choose a popular diagnostic method and define a

  4. Vitamin E analogues and immune response in cancer treatment

    Czech Academy of Sciences Publication Activity Database

    Tomasetti, M.; Neužil, Jiří

    2007-01-01

    Roč. 76, - (2007), s. 463-491 ISSN 0083-6729 Institutional research plan: CEZ:AV0Z50520514; CEZ:AV0Z50520701 Keywords : vitamin E analogues * inducers of apoptosis * immune surveillance Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 3.889, year: 2007

  5. Influence of Bakuchiol, a JH analogue from Bemchi ( Psoralea ...

    African Journals Online (AJOL)

    The influence of a juvenile hormone analogue (JHA), bakuchiol on the silk yield of silkworm, Bombyx mori L. was studied involving two popular commercial hybrids, KA x NB4D2 (bivoltine x bivoltine) and PM x NB4D2 (multivoltine x bivoltine). The compound was administered topically to 5th instars at 24, 48, 72 and 96 h as ...

  6. Thymidine analogues to assess microperfusion in human tumors

    International Nuclear Information System (INIS)

    Janssen, Hilde L.; Ljungkvist, Anna S.; Rijken, Paul F.; Sprong, Debbie; Bussink, Jan; Kogel, Albert J. van der; Haustermans, Karin M.; Begg, Adrian C.

    2005-01-01

    Purpose: To validate the use of the thymidine analogues as local perfusion markers in human tumors (no labeling indicates no perfusion) by comparison with the well-characterized perfusion marker Hoechst 33342. Methods and Materials: Human tumor xenografts from gliomas and head-and-neck cancers were injected with iododeoxyuridine (IdUrd) or bromodeoxyuridine (BrdUrd) and the fluorescent dye Hoechst 33342. In frozen sections, each blood vessel was scored for the presence of IdUrd/BrdUrd labeling and Hoechst in surrounding cells. The percentage of analogue-negative vessels was compared with the fraction of Hoechst-negative vessels. Collocalization of the two markers was also scored. Results: We found considerable intertumor variation in the fraction of perfused vessels, measured by analogue labeling, both in the human tumor xenografts and in a series of tumor biopsies from head-and-neck cancer patients. There was a significant correlation between the Hoechst-negative and IdUrd/BrdUrd-negative vessels in the xenografts (r 85, p = 0.0004), despite some mismatches on a per-vessel basis. Conclusions: Thymidine analogues can be successfully used to rank tumors according to their fraction of perfused vessels. Whether this fraction correlates with the extent of acute hypoxia needs further confirmation

  7. Mutasynthesis of fluorinated pactamycin analogues and their antimalarial activity.

    Science.gov (United States)

    Almabruk, Khaled H; Lu, Wanli; Li, Yuexin; Abugreen, Mostafa; Kelly, Jane X; Mahmud, Taifo

    2013-04-05

    A mutasynthetic strategy has been used to generate fluorinated TM-025 and TM-026, two biosynthetically engineered pactamycin analogues produced by Streptomyces pactum ATCC 27456. The fluorinated compounds maintain excellent activity and selectivity toward chloroquine-sensitive and multidrug-resistant strains of malarial parasites as the parent compounds. The results also provide insights into the biosynthesis of 3-aminobenzoic acid in S. pactum.

  8. Synthesis of ribavirin 2’-Me-C-nucleoside analogues

    Directory of Open Access Journals (Sweden)

    Fanny Cosson

    2017-04-01

    Full Text Available An efficient synthetic pathway leading to two carbonated analogues of ribavirin is described. The key-steps in the synthesis of these ribosyltriazoles bearing a quaternary carbon atom in the 2’-position are an indium-mediated alkynylation and a 1,3-dipolar cyclization.

  9. Using natural analogue studies in the secondary science curriculum

    International Nuclear Information System (INIS)

    Ebert, E.K.

    1995-01-01

    This paper discusses an atomic theory unit of a high school chemistry course taught in Nevada. The unit is based on the application of natural analogues to nuclear waste issues. The paper focuses on the students' reactions to the subject material

  10. Analogue Building Blocks Based on Digital CMOS Gates

    DEFF Research Database (Denmark)

    Mucha, Igor

    1996-01-01

    Low-performance analogue circuits built of digital MOS gates are presented. Depending on the threshold voltages of the technology used the final circuits can be operated using low supply voltages. The main advantage using the proposed circuits is the simplicity and ultimate compatibility...... with the design of digital circuits....

  11. Rubrene analogues with the aggregation-induced emission enhancement behaviour

    DEFF Research Database (Denmark)

    Zhang, Xiaoxu; Sørensen, Jakob Kryger; Fu, Xiaowei

    2014-01-01

    In the light of the principle of aggregation-induced emission enhancement (AIEE), the rubrene analogue with orange light-emitting properties is designed and synthesized by substituting the phenyl side groups of rubrene with thienyl groups. To the best of our knowledge, this is the first report on...

  12. Mammary analogue secretory carcinoma: A rare salivary gland tumour

    African Journals Online (AJOL)

    Salivary gland malignancy is rare, with a global annual incidence of. 3 per 100 000 people.[1,2] A rare salivary gland tumour, mammary analogue secretory carcinoma (MASC), has only recently been described.[3] The few reports and studies concerning MASC have been published in several pathology journals. We report ...

  13. Charged Analogues of Henning Knutsen Type Solutions in General Relativity

    Science.gov (United States)

    Gupta, Y. K.; Kumar, Sachin; Pratibha

    2011-11-01

    In the present article, we have found charged analogues of Henning Knutsen's interior solutions which join smoothly to the Reissner-Nordstrom metric at the pressure free interface. The solutions are singularity free and analyzed numerically with respect to pressure, energy-density and charge-density in details. The solutions so obtained also present the generalization of A.L. Mehra's solutions.

  14. Lysine-vasopressin analogues with glycoconjugates in position 8

    Czech Academy of Sciences Publication Activity Database

    Marcinkowska, A.; Borovičková, Lenka; Slaninová, Jiřina; Grzonka, Z.

    2006-01-01

    Roč. 80, č. 5 (2006), s. 759-766 ISSN 0137- 5083 Institutional research plan: CEZ:AV0Z40550506 Keywords : glycoconjugates * glycopeptides * lysine-vasopressin analogues Subject RIV: CC - Organic Chemistry Impact factor: 0.491, year: 2006

  15. Variation of Geochemical Signatures and Correlation of Biomarkers in Icelandic Mars Analogue Environments

    Science.gov (United States)

    Gentry, D.; Amador, E. S.; Cable, M. L.; Cantrell, T.; Chaudry, N.; Cullen, T.; Duca, Z. A.; Jacobsen, M. B.; McCaig, H. C.; Murukesan, G.; Rennie, V.; Schwieterman, E. W.; Stevens, A. H.; Tan, G.; Yin, C.; Stockton, A.; Cullen, D.; Geppert, W.

    2015-12-01

    Exploration missions to Mars rely on rovers to perform deep analyses over small sampling areas; however, landing site selection is done using large-scale but low-resolution remote sensing data. Using Earth analogue environments to estimate the small-scale spatial and temporal distributions of key geochemical signatures and (for habitability studies) biomarkers helps ensure that the chosen sampling strategies meet mission science goals. We conducted two rounds of analogue expeditions to recent Icelandic lava fields. In July 2013, we tested correlation between three common biomarker assays: cell quantification via fluorescence microscopy, ATP quantification via bioluminescence, and quantitative PCR with universal primer sets. Sample sites were nested at four spatial scales (1 m, 10 m, 100 m, and > 1 km) and homogeneous at 'remote imaging' resolution (overall temperature, apparent moisture content, and regolith grain size). All spatial scales were highly diverse in ATP, bacterial 16S, and archaeal 16S DNA content; nearly half of sites were statistically different in ATP content at α = 0.05. Cell counts showed significant variation at the 10 m and 100 m scale; at the > 1 km scale, the mean counts were not distinguishable, but the median counts were, indicating differences in underlying distribution. Fungal 18S DNA content similarly varied at 1 m, 10 m, and 100 m scales only. Cell counts were not correlated with ATP or DNA content at any scale. ATP concentration and DNA content for all three primer sets were positively correlated. Bacterial DNA content was positively correlated with archaeal and fungal DNA content, though archaeal correlation was weak. Fungal and archaeal correlation was borderline. In July 2015, we repeated the sampling strategy, with the addition of a smaller-scale sampling grid of 10 cm and a third > 1 km location. This expedition also measured reflectance of the tephra cover and preserved mineral samples for future Raman spectroscopy in order to

  16. Análogos de insulina Insulin analogues

    Directory of Open Access Journals (Sweden)

    Manuel E. Licea Puig

    2006-12-01

    diabetes mellitus (DM. The recombinant technology of deoxyribonucleic acid (DNA has allowed the development of human insulin; however, this has not totally solved the problems related to immunogenecity, among other problems. Therefore, the new technologies are applied to create insulin analogues. It is our purpose to review relevant pharmacological and clinical aspects related to the insulin analogues, as well as their usefulness in the treatment of DM. The insulin analogues result from biochemical modifications of human insulin. These modifications of the insulin molecule alter not only the absorption, but also the beginning and duration of the action, which offer advantages over the conventional insulins. At present, there are three rapid acting insulin analogues: insulin lispro, insulin aspart and glulisine; and three long acting analogues; glargine, detemir and albulin. Albulin is the latest long acting analogue reported. At present, it is being subjected to various in vitro and in vivo studies. Besides, there have been developed diverse formulations where the rapid acting insulin analogues are premixed with the long acting analogues. The rapid acting insulin analogues have showed a modest global benefit against the conventional insulins in type 1 diabetics. The long acting analogues focus their attention in those persons with DM with nocturnal hypoglycemic episodes. Longer term studies are necessary to confirm the safety and benefits of these preparations, as well as to determine their effect on the micro- and macroangiopathic complications of DM.

  17. Truncation studies of alpha-melanotropin peptides identify tripeptide analogues exhibiting prolonged agonist bioactivity.

    Science.gov (United States)

    Haskell-Luevano, C; Sawyer, T K; Hendrata, S; North, C; Panahinia, L; Stum, M; Staples, D J; Castrucci, A M; Hadley, M F; Hruby, V J

    1996-01-01

    Truncation studies of alpha-melanotropin peptides identify tripeptide analogues exhibiting prolonged agonist bioactivity: PEPTIDES 17(6) 995-1002, 1996.-Systematic analysis of fragment derivatives of the superpotent alpha-MSH analogue. Ac-Ser.Tyr-Ser-Nle4-Glu- His-DPhe7-Arg-Trp-Gly-Lys-Pro-Val-NH2(NDP-MSH), led to the discovery of tripeptide agonists possessing prolonged bioactivity in the frog skin assay. Of particular significance to this discovery was Ac-DPhe-Arg-DTrp-NH2, which was the most potent tripeptide in this series exhibiting sustained melanotropic activity. Different pharmacophore models appear to exist that are dependent on the substructure and stereochemistry of the MSH(6-9) "active site." The tripeptides Ac-DPhe-Arg-Trp-NH2, Ac-DPhe-Arg-DTrp-NH2, and Ac-DPhe-DArg-Trp-NH2 stereo-chemical combinations require only Phe7-Xaa8-Trp9, whereas Ac-DPhe-DArg-DTrp-NH2, Ac-Phe-Arg-DTrp-NH2, and Ac-Phe-Arg-Trp-NH2 additionally require His4 for minimal biological activity. Ac-DPhe-Arg-DTrp-NH2 represents a novel prototype lead for the development of MSH-based peptidomimetic agonists.

  18. Climate change impacts on the disposal environment: a climate analogue approach - 59274

    International Nuclear Information System (INIS)

    Leterme, Bertrand; Mallants, Dirk

    2012-01-01

    Document available in abstract form only. Full text of publication follows: The Belgian Agency for Radioactive Waste and Enriched Fissile Materials (ONDRAF/NIRAS) aims to develop a surface disposal facility for L/ILW in Dessel (North-East of Belgium). The objective of this study is to provide estimates for the next few millennia of both infiltration through the planned earth cover and groundwater recharge in the vicinity of the Dessel site. Available predictions of future temperature and precipitation often extend until AD 2100 only (e.g. IPCC). To circumvent this data limitation, we use existing records of climatic analogue stations deemed representative of future climates in Belgium. The following climate states are considered: DO (maritime temperate, present-day climate in Dessel), Cs/Cr (subtropical with dry summers/no rainfall seasonality), EO (cold without permafrost) and FT (cold with permafrost). Climate data is then used in 1-D modelling of the soil-plant-atmosphere system to quantify infiltration through the earth cover and recharge to groundwater for a sequence of probable future climate states. Using criteria including altitude, distance to moisture source, and atmospheric circulation system, several analogue stations were selected for each climate state Cs/Cr and EO/FT. They provided time series (30 years) of meteorological observations that allowed calculating potential evapotranspiration and water balance components for soils overlying the repository

  19. Sulphamoylated 2-methoxyestradiol analogues induce apoptosis in adenocarcinoma cell lines.

    Directory of Open Access Journals (Sweden)

    Michelle Visagie

    Full Text Available 2-Methoxyestradiol (2ME2 is a naturally occurring estradiol metabolite which possesses antiproliferative, antiangiogenic and antitumor properties. However, due to its limited biological accessibility, synthetic analogues have been synthesized and tested in attempt to develop drugs with improved oral bioavailability and efficacy. The aim of this study was to evaluate the antiproliferative effects of three novel in silico-designed sulphamoylated 2ME2 analogues on the HeLa cervical adenocarcinoma cell line and estrogen receptor-negative breast adenocarcinoma MDA-MB-231 cells. A dose-dependent study (0.1-25 μM was conducted with an exposure time of 24 hours. Results obtained from crystal violet staining indicated that 0.5 μM of all 3 compounds reduced the number of cells to 50%. Lactate dehydrogenase assay was used to assess cytotoxicity, while the mitotracker mitochondrial assay and caspase-6 and -8 activity assays were used to investigate the possible occurrence of apoptosis. Tubulin polymerization assays were conducted to evaluate the influence of these sulphamoylated 2ME2 analogues on tubulin dynamics. Double immunofluorescence microscopy using labeled antibodies specific to tyrosinate and detyrosinated tubulin was conducted to assess the effect of the 2ME2 analogues on tubulin dynamics. An insignificant increase in the level of lactate dehydrogenase release was observed in the compounds-treated cells. These sulphamoylated compounds caused a reduction in mitochondrial membrane potential, cytochrome c release and caspase 3 activation indicating apoptosis induction by means of the intrinsic pathway in HeLa and MDA-MB-231 cells. Microtubule depolymerization was observed after exposure to these three sulphamoylated analogues.

  20. Neurochemical binding profiles of novel indole and benzofuran MDMA analogues.

    Science.gov (United States)

    Shimshoni, Jakob A; Winkler, Ilan; Golan, Ezekiel; Nutt, David

    2017-01-01

    3,4-Methylenedioxy-N-methylamphetamine (MDMA) has been shown to be effective in the treatment of post-traumatic stress disorder (PTSD) in numerous clinical trials. In the present study, we have characterized the neurochemical binding profiles of three MDMA-benzofuran analogues (1-(benzofuran-5-yl)-propan-2-amine, 5-APB; 1-(benzofuran-6-yl)-N-methylpropan-2-amine, 6-MAPB; 1-(benzofuran-5-yl)-N-methylpropan-2-amine, 5-MAPB) and one MDMA-indole analogue (1-(1H-indol-5-yl)-2-methylamino-propan-1-ol, 5-IT). These compounds were screened as potential second-generation anti-PTSD drugs, against a battery of human and non-human receptors, transporters, and enzymes, and their potencies as 5-HT 2 receptor agonist and monoamine uptake inhibitors determined. All MDMA analogues displayed high binding affinities for 5-HT 2a,b,c and NE α2 receptors, as well as significant 5-HT, DA, and NE uptake inhibition. 5-APB revealed significant agonist activity at the 5-HT 2a,b,c receptors, while 6-MAPB, 5-MAPB, and 5-IT exhibited significant agonist activity at the 5-HT 2c receptor. There was a lack of correlation between the results of functional uptake and the monoamine transporter binding assay. MDMA analogues emerged as potent and selective monoamine oxidase A inhibitors. Based on 6-MAPB favorable pharmacological profile, it was further subjected to IC 50 determination for monoamine transporters. Overall, all MDMA analogues displayed higher monoamine receptor/transporter binding affinities and agonist activity at the 5-HT 2a,c receptors as compared to MDMA.

  1. Analogue Electrical Circuit for Simulation of the Duffing-Holmes Equation

    DEFF Research Database (Denmark)

    Tamaseviciute, E.; Tamasevicius, A.; Mykolaitis, G.

    2008-01-01

    An extremely simple second order analogue electrical circuit for simulating the two-well Duffing-Holmes mathematical oscillator is described. Numerical results and analogue electrical simulations are illustrated with the snapshots of chaotic waveforms, phase portraits (Lissajous figures...

  2. Field Comparisons of Three Biomarker Detection Methods in Icelandic Mars Analogue Environments

    Science.gov (United States)

    Gentry, D.; Amador, E. S.; Cable, M. L.; Chaudry, N.; Cullen, T.; Jacobsen, M.; Murusekan, G.; Schwieterman, E.; Stevens, A.; Stockton, A.; Yin, C.; Cullen, D.; Geppert, W.

    2014-12-01

    The ability to estimate the spatial and temporal distributions of biomarkers has been identified as a key need for planning life detection strategies. In a typical planetary exploration scenario, sampling site selection will be informed only by remote sensing data; however, if a difference of a few tens of meters, or centimeters, makes a significant difference in the results, science objectives may not be met. We conducted an analogue planetary expedition to test the correlation of three common biomarker detection methods -- cell counts through fluorescence microscopy, ATP quantification, and quantitative PCR with universal primer sets (bacteria, archaea, and fungi) -- and their spatial scale representativeness. Sampling sites in recent Icelandic lava fields (Fimmvörđuháls and Eldfell) spanned four nested spatial scales: 1 m, 10 m, 100 m, and > 1 km. Each site was homogeneous at typical 'remote sampling' resolution (overall temperature, apparent moisture content, and regolith grain size). No correlation between cell counts and either ATP or qPCR data was significant at any distance scale; ATP quantification and the archaeal and fungal qPCR data showed a marginal negative correlation at the 1 m level. Visible cell count data was statistically site-dependent for sites 10 m and 100 m apart, but not for sites > 1 km apart, whereas ATP results and qPCR data showed site dependence at all four scales. Distance had no significant effect on variability in cell counts and qPCR data, but was positively correlated with ATP variability. These results highlight the difficulty of choosing a 'good' biomarker: not only may different methods yield conflicting results, but they may also be differentially representative of the overall area. We intend to expand on this work with a follow-up campaign using comprehensive assays of physicochemical site properties to better distinguish between effects of environmental variability and intrinsic biomarker variability.

  3. The Tournemire industrial analogue: reactive-transport modelling of cement-clay interfaces

    International Nuclear Information System (INIS)

    Watson, C.; Wilson, J.; Benbow, S.; Savage, D.; Walker, C.; Norris, S.

    2012-01-01

    Document available in extended abstract form only. In a number of concepts for geological disposal facilities (GDFs) for radioactive waste, cement-based materials are used for a variety of purposes including mechanical support, backfilling of cavities, grouting of fractures in the host rock, and immobilisation of radionuclides in waste-forms. Such facilities will ultimately re-saturate with encroaching groundwater, at which point leaching of the cement components is likely to give rise to an alkaline pore fluid, regardless of cement type. This pore fluid will be in disequilibrium with both the host rock and other engineered barrier system (EBS) materials used in the construction of the facility, such as bentonite. The interaction of the pore fluid could lead, for example, to the reduction in the swelling capacity of the clay, alteration of porosity and permeability both in the host rock and in EBS materials, and reduction of sorption capacities. Analogue systems can provide information about hyper-alkaline alteration that it is not possible to obtain from short-term experimental studies alone, because they have evolved in situ over many tens, hundreds or thousands of years. These systems can be used to improve scientific understanding and consequently mathematical models, which in turn can be used to simulate the performance of the engineered and natural materials over the lifetime of the GDF. Industrial analogues provide a kind of 'halfway house' between natural analogues and laboratory experimental studies; the initial and boundary conditions are often better understood than natural analogues, and the timescales involved, whilst much shorter than natural analogues, are generally of much greater duration than laboratory studies. One such analogue can be found at Tournemire, southern France, where a tunnel excavated in the 1880's had several exploration boreholes drilled into its basement in the 1990's. These boreholes were then filled with concrete and cement

  4. Identificación de asentamientos irregulares y diagnóstico de sus necesidades de infraestructura en Ciudad Juárez, Chihuahua, México

    Directory of Open Access Journals (Sweden)

    Ivan Elias Ruiz Hernandez

    2015-01-01

    ón remota, análisis espacial e información censal. Los atributos físicos incluyen las condiciones del terreno, disección vertical y zonas de riesgo geológico y de inundación. Los atributos socioeconómicos incluyen, polígonos de pobreza, cobertura de agua potable y drenaje, nivel de hacinamiento, relación centro-periferia y valor del suelo. Los atributos de organización espacial y tipo de materiales de construcción, fueron recabados de imágenes satelitales de alta resolución y métricas de paisaje. Estos tres grupos de variables fueron integrados en un modelo multicriterio para la identificación de AI en Ciudad Juárez, Chihuahua, México. El modelo permite no solo la identificación de dichos AI sino también la realización de un diagnóstico de sus necesidades de infraestructura y servicios urbanos contando con un nivel de exactitud del 97.66%. Esta investigación presenta un método nuevo y confiable para la identificación de AI y a su vez los resultados obtenidos proveen una importante herramienta para los responsables del desarrollo urbano en la toma de decisiones.

  5. Deficiencies in fat-soluble vitamins in long-term users of somatostatin analogue

    NARCIS (Netherlands)

    Fiebrich, H. -B.; van den Berg, G.; Kema, I. P.; Links, T. P.; Kleibeuker, J. H.; van Beek, A. P.; Walenkamp, A. M. E.; Sluiter, W. J.; de Vries, E. G. E.

    2010-01-01

    P>Background Somatostatin analogues are administered to control hormone hypersecretion in acromegaly and carcinoid patients. Somatostatin analogues can increase fat in the stools, which can lead to loss of fat-soluble vitamins. The effect of long-term somatostatin analogue use on vitamin levels

  6. Nucleoside analogues are activated by bacterial deoxyribonucleoside kinases in a species-specific manner

    DEFF Research Database (Denmark)

    Sandrini, Michael; Clausen, Anders; On, Stephen L. W.

    2007-01-01

    To investigate the bactericidal activity of antiviral and anticancer nucleoside analogues against a variety of pathogenic bacteria and characterize the activating enzymes, deoxyribonucleoside kinases (dNKs). Several FDA-approved nucleoside analogue drugs were screened for their potential bacteric......-specific manner. Therefore, nucleoside analogues have a potential to be employed as antibiotics in the fight against emerging multiresistant bacteria....

  7. On Using Current Steering Logic in Mixed Analogue-digital Circuits

    DEFF Research Database (Denmark)

    Lehmann, Torsten

    1998-01-01

    The authors investigate power supply noise in mixed analogue-digital circuits, arising from communication between the analogue and digital parts of the circuit. Current steering techniques and proper buffering are used to show which noise currents can be reduced and which cannot. In addition......, a high-swing current steering buffer for driving analogue switches or external digital signals is proposed....

  8. Synthesis and antioxidant activity of peptide-based ebselen analogues.

    Science.gov (United States)

    Satheeshkumar, Kandhan; Mugesh, Govindasamy

    2011-04-18

    A series of di- and tripeptide-based ebselen analogues has been synthesized. The compounds were characterized by (1)H, (13)C, and (77)Se NMR spectroscopy and mass spectral techniques. The glutathione peroxidase (GPx)-like antioxidant activity has been studied by using H(2)O(2) , tert-butyl hydroperoxide (tBuOOH), and cumene hydroperoxide (Cum-OOH) as substrates, and glutathione (GSH) as a cosubstrate. Although all the peptide-based compounds have a selenazole ring similar to that of ebselen, the GPx activity of these compounds highly depends on the nature of the peptide moiety attached to the nitrogen atom of the selenazole ring. It was observed that the introduction of a phenylalanine (Phe) amino acid residue in the N-terminal reduces the activity in all three peroxide systems. On the other hand, the introduction of aliphatic amino acid residues such as valine (Val) significantly enhances the GPx activity of the ebselen analogues. The difference in the catalytic activity of dipeptide-based ebselen derivatives can be ascribed mainly to the change in the reactivity of these compounds toward GSH and peroxide. Although the presence of the Val-Ala-CO(2) Me moiety facilitates the formation of a catalytically active selenol species, the reaction of ebselen analogues that has a Phe-Ile-CO(2) Me residue with GSH does not generate the corresponding selenol. To understand the antioxidant activity of the peptide-based ebselen analogues in the absence of GSH, these compounds were studied for their ability to inhibit peroxynitrite (PN)-mediated nitration of bovine serum albumin (BSA) and oxidation of dihydrorhodamine 123. In contrast to the GPx activity, the PN-scavenging activity of the Phe-based peptide analogues was found to be comparable to that of the Val-based compounds. However, the introduction of an additional Phe residue to the ebselen analogue that had a Val-Ala dipeptide significantly reduced the potency of the parent compound in PN-mediated nitration. Copyright

  9. Phosphorylation of inositol 1,4,5-trisphosphate analogues by 3-kinase and dephosphorylation of inositol 1,3,4,5-tetrakisphosphate analogues by 5-phosphatase

    NARCIS (Netherlands)

    Dijken, Peter van; Lammers, Aleida A.; Ozaki, Shoichiro; Potter, Barry V.L.; Erneux, Christophe; Haastert, Peter J.M. van

    1994-01-01

    A series of P-32-labeled D-myo-inositol 1,3,4,5-tetrakisphosphate [Ins(1,3,4,5)P-4] analogues was enzymically prepared from the corresponding D-myo-inositol 1,4,5-trisphosphate [Ins(1,4,5)P-3] analogues using recombinant rat brain Ins(1,4,5)P-3 3-kinase and [gamma-P-32]ATP. Ins(1,4,5)P-3 analogues

  10. Radionuclide migration in the geosphere: modelling of the natural analogue of needle's eye

    International Nuclear Information System (INIS)

    Doublet, R.; Jamet, P.; Lachassagne, P.; Ledoux, E.

    1990-01-01

    The study of the natural analogue of Needle's Eye (Scotland) has covered a three years period. It involved an important field and laboratory work, though delicate considering the peculiar site constraints (which is a natural reserve). The collaboration between BGS and SURRC geologists and geochemists on the one hand, and the modelling team of CIG on the other hand made it possible to collate an adequate and consistent database prior to a fruiful modelling work. In conclusion, the work that has been carried out enlights the applicability of a coupled model to a real case. This approach could be extended to other case studies. However, an important work remains to be done in order to strenghten the first encouraging results of the Needle's Eye model. This work is part of the community programme Mirage

  11. The Palmottu Analogue Project, Progress Report 1993. The behaviour of natural radionuclides in and around uranium deposits, Nr. 7

    International Nuclear Information System (INIS)

    Ruskeeniemi, T.; Blomqvist, R.; Suksi, J.; Niini, H.

    1994-01-01

    The report gives a summary of the results of investigations carried out in 1993 at the Palmottu natural analogue study site, which comprises a small U-Th mineralization in Nummi-Pusula, southwestern Finland. Additionally, the report includes several separate articles dealing with various aspects of the Palmottu Analogue Project: (1) 3-dimensional model of fracture zones, (2) redox chemistry of uranium in groundwater, (3) humic substances in groundwater, (4) uranium mineralogy, (5) importance of selective extractions in uranium migration studies, (6) modelling of matrix diffusion, and (7) uranium in surficial deposits. The Palmottu Analogue Project aims at a more profound understanding of radionuclide transport processes in fractured crystalline bedrock. The essential factors controlling transport are groundwater flow and interaction between water and rock. Accordingly, the study includes (1) structural interpretations partly based on geophysical measurements, (2) hydrological studies including hydraulic drill-hole measurements, (3) flow modelling, (4) hydrogeochemical characterization of groundwater, uranium chemistry and colloid chemistry, (5) mineralogical studies, (6) geochemical interpretation and modelling, (7) studies on mobilization and retardation of uranium, and (8) modelling of uranium series data. Paleohydrogeological aspects are of special interest, due to the anticipated future glaciation of the Fennoscandian Shield. Surficial sediments and waters are studied to gain information on postglacial migration in the overburden. (orig.)

  12. The Palmottu natural analogue project. The behaviour of natural radionuclides in and around uranium deposits. Summary report 1992-1994

    Energy Technology Data Exchange (ETDEWEB)

    Blomqvist, R; Ruskeeniemi, T; Ahonen, L [Geological Survey of Finland, Espoo (Finland); Suksi, J [Helsinki Univ. (Finland). Lab. of Radiochemistry; Niini, H [Helsinki Univ. of Technology, Otaniemi (Finland). Lab. of Engineering Geology and Geophysics; Vuorinen, U [VTT Chemical Technology, Espoo (Finland); Jakobsson, K [Finnish Centre for Radiation and Nuclear Safety, Helsinki (Finland)

    1995-06-01

    The Palmottu U-Th mineralization at Nummi-Pusula, southwestern Finland, has been studied as a natural analogue to deep disposal of radioactive wastes since 1988. The report gives a summary of the results of investigations carried out during the years 1992-1994. The Palmottu Analogue Project aims at a more profound understanding of radionuclide transport processes in fractured crystalline bedrock. The essential factors controlling transport are groundwater flow and interaction between water and rock. Accordingly, the study includes structural interpretations based in part on geophysical measurements, hydrological studies including hydraulic downhole measurements, flow modelling, hydrogeochemical characterization of groundwater, uranium chemistry and colloid chemistry, mineralogical studies, geochemical interpretation and modelling, including paleohydrogeological aspects, and studies of radionuclide mobilization and migration processes including numerical simulations. The project has produced a large amount of data related to natural analogue aspects. The data obtained have already been utilized in developing logical conceptual ideas of the time frames and processes operating in the bedrock of the site. (61 refs., 24 figs., 8 tabs.).

  13. The Palmottu natural analogue project. The behaviour of natural radionuclides in and around uranium deposits. Summary report 1992-1994

    International Nuclear Information System (INIS)

    Blomqvist, R.; Ruskeeniemi, T.; Ahonen, L.; Suksi, J.; Jakobsson, K.

    1995-06-01

    The Palmottu U-Th mineralization at Nummi-Pusula, southwestern Finland, has been studied as a natural analogue to deep disposal of radioactive wastes since 1988. The report gives a summary of the results of investigations carried out during the years 1992-1994. The Palmottu Analogue Project aims at a more profound understanding of radionuclide transport processes in fractured crystalline bedrock. The essential factors controlling transport are groundwater flow and interaction between water and rock. Accordingly, the study includes structural interpretations based in part on geophysical measurements, hydrological studies including hydraulic downhole measurements, flow modelling, hydrogeochemical characterization of groundwater, uranium chemistry and colloid chemistry, mineralogical studies, geochemical interpretation and modelling, including paleohydrogeological aspects, and studies of radionuclide mobilization and migration processes including numerical simulations. The project has produced a large amount of data related to natural analogue aspects. The data obtained have already been utilized in developing logical conceptual ideas of the time frames and processes operating in the bedrock of the site. (61 refs., 24 figs., 8 tabs.)

  14. Binding interactions between yeast tRNA ligase and a precursor transfer ribonucleic acid containing two photoreactive uridine analogues

    International Nuclear Information System (INIS)

    Tanner, N.K.; Hanna, M.M.; Abelson, J.

    1988-01-01

    Yeast tRNA ligase, from Saccharomyces cerevisiae, is one of the protein components that is involved in the splicing reaction of intron-containing yeast precursor tRNAs. It is an unusual protein because it has three distinct catalytic activities. It functions as a polynucleotide kinase, as a cyclic phosphodiesterase, and as an RNA ligase. We have studied the binding interactions between ligase and precursor tRNAs containing two photoreactive uridine analogues, 4-thiouridine and 5-bromouridine. When irradiated with long ultraviolet light, RNA containing these analogues can form specific covalent bonds with associated proteins. In this paper, we show that 4-thiouridine triphosphate and 5-bromouridine triphosphate were readily incorporated into a precursor tRNA(Phe) that was synthesized, in vitro, with bacteriophage T7 RNA polymerase. The analogue-containing precursor tRNAs were authentic substrates for the two splicing enzymes that were tested (endonuclease and ligase), and they formed specific covalent bonds with ligase when they were irradiated with long-wavelength ultraviolet light. We have determined the position of three major cross-links and one minor cross-link on precursor tRNA(Phe) that were located within the intron and near the 3' splice site. On the basis of these data, we present a model for the in vivo splicing reaction of yeast precursor tRNAs

  15. Peramivir analogues bearing hydrophilic side chains exhibit higher activities against H275Y mutant than wild-type influenza virus.

    Science.gov (United States)

    Chiu, Din-Chi; Lin, Tzu-Chen; Huang, Wen-I; Cheng, Ting-Jen; Tsai, Keng-Chang; Fang, Jim-Min

    2017-11-29

    Peramivir is an effective anti-influenza drug in the clinical treatment of influenza, but its efficacy toward the H275Y mutant is reduced. The previously reported cocrystal structures of inhibitors in the mutant neuraminidase (NA) suggest that the hydrophobic side chain should be at the origin of reduced binding affinity. In contrast, zanamivir having a hydrophilic glycerol side chain still possesses high affinity toward the H275Y NA. We thus designed five peramivir analogues (5-9) carrying hydrophilic glycol or glycerol side chains, and evaluated their roles in anti-influenza activity, especially for the H275Y mutant. The synthetic sequence involves a key step of (3 + 2) cycloaddition reactions between alkenes and nitrile oxides to construct the scaffold of peramivir carrying the desired hydrophilic side chains and other appropriate functional groups. The molecular docking experiments reveal that the hydrophilic side chain can provide extra hydrogen bonding with the translocated Glu-276 residue in the H275Y NA active site. Thus, the H275Y mutant may be even more sensitive than wild-type virus toward the peramivir analogues bearing hydrophilic side chains. Notably, the peramivir analogue bearing a glycerol side chain inhibits the H275Y mutant with an IC 50 value of 35 nM, which is better than the WSN virus by 9 fold.

  16. Production of New Cladosporin Analogues by Reconstitution of the Polyketide Synthases Responsible for the Biosynthesis of this Antimalarial Agent.

    Science.gov (United States)

    Cochrane, Rachel V K; Sanichar, Randy; Lambkin, Gareth R; Reiz, Béla; Xu, Wei; Tang, Yi; Vederas, John C

    2016-01-11

    The antimalarial agent cladosporin is a nanomolar inhibitor of the Plasmodium falciparum lysyl-tRNA synthetase, and exhibits activity against both blood- and liver-stage infection. Cladosporin can be isolated from the fungus Cladosporium cladosporioides, where it is biosynthesized by a highly reducing (HR) and a non-reducing (NR) iterative type I polyketide synthase (PKS) pair. Genome sequencing of the host organism and subsequent heterologous expression of these enzymes in Saccharomyces cerevisiae produced cladosporin, confirming the identity of the putative gene cluster. Incorporation of a pentaketide intermediate analogue indicated a 5+3 assembly by the HR PKS Cla2 and the NR PKS Cla3 during cladosporin biosynthesis. Advanced-intermediate analogues were synthesized and incorporated by Cla3 to furnish new cladosporin analogues. A putative lysyl-tRNA synthetase resistance gene was identified in the cladosporin gene cluster. Analysis of the active site emphasizes key structural features thought to be important in resistance to cladosporin. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. The Greenland Analogue Project. Yearly Report 2010

    International Nuclear Information System (INIS)

    Harper, J.; Hubbard, A.; Ruskeeniemi, T.

    2011-12-01

    the larger ice sheet hydrology and groundwater formation project (i.e. SPA and SPB combined) and will provide pioneering measurements of subglacial water pressures on a full ice sheet scale. This information will provide important input to the conceptualization of hydraulic gradients during glacial conditions for groundwater models applicable in Fennoscandia and Canada, including their spatial and temporal variation. Results from SPA are necessary for the selection of suitable drilling locations. Sub-project C, (SPC), Bedrock drilling, hydrogeochemistry and hydrogeology. SPC aims at studying the penetration of glacial meltwater into the bedrock, groundwater flow dynamics, and the chemical composition of water when, and if, it reaches repository depth (around 500 m down in the bedrock). Main activities for SPC involve deep bedrock drilling in front of the ice sheet for subsequent down hole surveys and hydrogeological/hydrogeochemical instrumentation, sampling and monitoring. The deep drilling requires a detailed understanding of the geology of the area, including fracture frequencies and composition of rock types and hydrogeochemical information (i.e. chemistry of different water end-members). Before selecting a site for the deep drilling, test drilling of two shallow holes (100-300 meters) were carried out. In addition to providing important information on geology and hydrology, the test drilling has also given useful information on the permafrost extent. In order to study if taliks may act as discharge points for deep groundwater formed under the ice sheet, one of the test holes has been drilled into a presumed talik. Data from SPA, and understanding of the ice sheet hydrology, are necessary for proper selection of the drilling location of the deep borehole. Data on water formation and chemistry at the base of the ice sheet, collected as part of SPB, will be important when analyzing the results of SPC

  18. The Greenland Analogue Project. Yearly Report 2010

    Energy Technology Data Exchange (ETDEWEB)

    Harper, J [Univ. of Montana (United States); Hubbard, A [Aberystwyth Univ. (United Kingdom); Ruskeeniemi, T [Geological Survey of Finland (Finland); and others

    2011-12-15

    the larger ice sheet hydrology and groundwater formation project (i.e. SPA and SPB combined) and will provide pioneering measurements of subglacial water pressures on a full ice sheet scale. This information will provide important input to the conceptualization of hydraulic gradients during glacial conditions for groundwater models applicable in Fennoscandia and Canada, including their spatial and temporal variation. Results from SPA are necessary for the selection of suitable drilling locations. Sub-project C, (SPC), Bedrock drilling, hydrogeochemistry and hydrogeology. SPC aims at studying the penetration of glacial meltwater into the bedrock, groundwater flow dynamics, and the chemical composition of water when, and if, it reaches repository depth (around 500 m down in the bedrock). Main activities for SPC involve deep bedrock drilling in front of the ice sheet for subsequent down hole surveys and hydrogeological/hydrogeochemical instrumentation, sampling and monitoring. The deep drilling requires a detailed understanding of the geology of the area, including fracture frequencies and composition of rock types and hydrogeochemical information (i.e. chemistry of different water end-members). Before selecting a site for the deep drilling, test drilling of two shallow holes (100-300 meters) were carried out. In addition to providing important information on geology and hydrology, the test drilling has also given useful information on the permafrost extent. In order to study if taliks may act as discharge points for deep groundwater formed under the ice sheet, one of the test holes has been drilled into a presumed talik. Data from SPA, and understanding of the ice sheet hydrology, are necessary for proper selection of the drilling location of the deep borehole. Data on water formation and chemistry at the base of the ice sheet, collected as part of SPB, will be important when analyzing the results of SPC

  19. 5-Iodo-2-aminoindan, a nonneurotoxic analogue of p-iodoamphetamine

    International Nuclear Information System (INIS)

    Nichols, D.E.; Johnson, M.P.; Oberlender, R.

    1991-01-01

    A rigid analogue, 5-iodo-2-aminoindan (5-IAI), of the serotonin neurotoxic halogenated amphetamine p-iodoamphetamine (PIA) was pharmacologically evaluated for production of serotonin neurotoxicity. A comparison was also made between 5-IAI and PIA in the two-lever drug discrimination paradigm in rats trained to discriminate saline from 3,4-methylenedioxymethamphetamine (MDMA) or saline from the alpha-ethyl homologue of MDMA, MBDB. PIA and 5-IAI were both behaviorally active, and fully substituted in both groups of animals, but were considerably less potent than p-chloroamphetamine (PCA). PIA had about twice the potency of PCA as an inhibitor of 3 H-5-HT uptake in rat brain cortical synaptosomes, while 5-IAI was only about 75% as potent as PCA in this assay. A single 40 mg/kg dose of PIA resulted in a 40% reduction of 5-HT and 5-HIAA levels and in the number of 5-HT uptake sites in rat cortex at one week sacrifice. The same dose of 5-IAI with one week sacrifice led to about a 15% decrease in 5-HIAA levels and number of 5-HT uptake sites, but only the latter was statistically significant. In rat hippocampus, PIA gave significant decreases in all serotonin markers examined, while 5-IAI slightly but significantly decreased only 5-HT levels. Neither compound produced any change in catecholamine or catecholamine metabolite levels. The results confirm earlier reports of the selective serotonin neurotoxicity of PIA, which is less severe than that of PCA, and also demonstrate that its rigid analogue 5-IAI does not appear to cause significant serotonin deficits in the rat

  20. Cold, Gas-Phase UV and IR Spectroscopy of Protonated Leucine Enkephalin and its Analogues

    Science.gov (United States)

    Burke, Nicole L.; Redwine, James; Dean, Jacob C.; McLuckey, Scott A.; Zwier, Timothy S.

    2014-06-01

    The conformational preferences of peptide backbones and the resulting hydrogen bonding patterns provide critical biochemical information regarding the structure-function relationship of peptides and proteins. The spectroscopic study of cryogenically-cooled peptide ions in a mass spectrometer probes these H-bonding arrangements and provides information regarding the influence of a charge site. Leucine enkephalin, a biologically active endogenous opiod peptide, has been extensively studied as a model peptide in mass spectrometry. This talk will present a study of the UV and IR spectroscopy of protonated leucine enkephalin [YGGFL+H]+ and two of its analogues: the sodiated [YGGFL+Na]+ and C-terminally methyl esterified [YGGFL-OMe+H]+ forms. All experiments were performed in a recently completed multi-stage mass spectrometer outfitted with a cryocooled ion trap. Ions are generated via nano-electrospray ionization and the analyte of interest is isolated in a linear ion trap. The analyte ions are trapped in a 22-pole ion trap held at 5 K by a closed cycle helium cryostat and interrogated via UV and IR lasers. Photofragments are trapped and isolated in a second LIT and mass analyzed. Double-resonance UV and IR methods were used to assign the conformation of [YGGFL+H]+, using the NH/OH stretch, Amide I, and Amide II regions of the infrared spectrum. The assigned structure contains a single backbone conformation at vibrational/rotational temperatures of 10 K held together with multiple H-bonds that self-solvate the NH3+ site. A "proton wire" between the N and C termini reinforces the H-bonding activity of the COO-H group to the F-L peptide bond, whose cleavage results in formation of the b4 ion, which is a prevalent, low-energy fragmentation pathway for [YGGFL+H]+. The reinforced H-bonding network in conjunction with the mobile proton theory may help explain the prevalence of the b4 pathway. In order to elucidate structural changes caused by modifying this H-bonding activity