Sample records for nam ghi ch

  1. Gross CO2 and CH4 emissions from the Nam Ngum and Nam Leuk sub-tropical reservoirs in Lao PDR.

    PubMed

    Chanudet, Vincent; Descloux, Stéphane; Harby, Atle; Sundt, Håkon; Hansen, Bjørn Henrik; Brakstad, Odd; Serça, Dominique; Guerin, Frédéric

    2011-11-15

    Gross CO2 and CH4 emissions (degassing and diffusion from the reservoir) and the carbon balance were assessed in 2009-2010 in two Southeast Asian sub-tropical reservoirs: the Nam Ngum and Nam Leuk Reservoirs (Lao PDR). These two reservoirs are within the same climatic area but differ mainly in age, size, residence time and initial biomass stock. The Nam Leuk Reservoir was impounded in 1999 after partial vegetation clearance and burning. However, GHG emissions are still significant 10 years after impoundment. CH4 diffusive flux ranged from 0.8 (January 2010) to 11.9 mmol m(-2) d(-1) (April 2009) and CO2 diffusive flux ranged from -10.6 (October 2009) to 38.2 mmol m(-2) d(-1) (April 2009). These values are comparable to other tropical reservoirs. Moreover, degassing fluxes at the outlet of the powerhouse downstream of the turbines were very low. The tentative annual carbon balance calculation indicates that this reservoir was a carbon source with an annual carbon export (atmosphere+downstream river) of about 2.2±1.0 GgC yr(-1). The Nam Ngum Reservoir was impounded in 1971 without any significant biomass removal. Diffusive and degassing CO2 and CH4 fluxes were lower than for other tropical reservoirs. Particularly, CO2 diffusive fluxes were always negative with values ranging from -21.2 (April 2009) to -2.7 mmol m(-2) d(-1) (January 2010). CH4 diffusive flux ranged from 0.1 (October 2009) to 0.6 mmol m(-2) d(-1) (April 2009) and no degassing downstream of the turbines was measured. As a consequence of these low values, the reservoir was a carbon sink with an estimated annual uptake of - 53±35 GgC yr(-1). Copyright © 2011 Elsevier B.V. All rights reserved.

  2. Genotoxicity-Related Chemistry of Human Metabolites of Benzo[ghi]perylene (B[ghi]P) Investigated using Electro-optical Arrays and DNA/Microsome Biocolloid Reactors with LC-MS/MS

    PubMed Central

    Pan, Shenmin; Li, Dandan; Zhao, Linlin; Schenkman, John B.; Rusling, James F.

    2013-01-01

    There is limited and sometimes contradictory information about the genotoxicity of polycyclic aromatic hydrocarbon benzo[ghi]perylene (B[ghi]P). Using recently developed metabolic toxicity screening arrays and a biocolloid reactor-LC-MS/MS approach, both featuring films of DNA and human metabolic enzymes, we demonstrated relatively low reactivity of metabolically activated B[ghi]P towards DNA. Electro-optical toxicity screening arrays showed that B[ghi]P metabolites damage DNA at a 3-fold lower rate than benzo[a]pyrene (B[a]P), whose metabolites have a strong and well-understood propensity for DNA damage. Metabolic studies using magnetic bead biocolloid reactors coated with microsomal enzymes in 96-well plates showed that cyt P450s 1A1 and 1B1 provide high activity for B[ghi]P and B[a]P conversion. Consistent with published results, the major metabolism of B[ghi]P involved oxidations at 3,4 and 11,12 positions, leading to formation of B[ghi]P 3,4-oxide and B[ghi]P 3,4,11,12-bisoxide. B[ghi]P 3,4-oxide was synthesized and reacted with deoxyadenosine at N6 and N7 positions and with deoxyguanosine at the N2 position. B[ghi]P 3,4-oxide is hydrolytically unstable and transforms into the 3,4-diol or converts to 3- or 4-hydroxy B[ghi]P. LC-MS/MS of reaction products from the magnetic biocolloid reactor particles coated with DNA and human enzymes revealed for the first time that a major DNA adduct results from reaction between B[ghi]P 3,4,11,12-bisoxide and deoxyguanosine. Results also demonstrated 5-fold lower formation rates of the major DNA adduct for B[ghi]P metabolites compared to B[a]P. Overall, results from both ECL array and biocolloid reactor-LC-MS/MS consistently suggest a lower human genotoxicity profile of B[ghi]P than B[a]P. PMID:23879290

  3. HỖ TRỢ CỦA GIA ĐÌNH ĐỐI VỚI NAM TIÊM CHÍCH MA TÚY NHIỄM HIV TẠI HÀ NỘI

    PubMed Central

    Ngọc, Lùng Bích; Ly, An Thanh; Hòa, Trần Thị; Giang, Lê Minh

    2016-01-01

    Nghiên cứu định tính nhằm mô tả hỗ trợ của gia đình trong chăm sóc sức khỏe, đặc biệt trong điều trị HIV và nghiện chắt của nam tiêm chích ma túy nhiễm HIV tại Hà Nội. Kết quả phân tích cho thấy gia đình chủ yếu hỗ trợ tài chính, tinh thần và chăm sóc sức khỏe trong khi các hỗ trợ thông tin liên quan đến điều trị HIV và nghiện chất cho nam tiêm chích ma túy nhiễm HIV của gia đình còn khá hạn chế. Hỗ trợ của gia đình cho nam tiêm chích ma túy nhiễm HIV khác nhau giữa các giai đoạn sử dụng ma túy, nhiễm HIV, điều trị HIV và điều trị nghiện chất. Đáng chú ý là việc tiết lộ tình trạng nhiễm HIV đã giúp các nam tiêm chích ma túy nhận được nhiều hơn sự hỗ trợ từ gia đình. Các can thiệp nhằm nâng cao hiệu quả điều trị HIV và điều trị nghiện chất cho nam tiêm chích ma túy nhiễm HIV cần tính đến sự tham gia hỗ trợ của gia đình. PMID:28393100

  4. Trầm Cảm Ở Thành Viên Gia Đình Của Nam Tiêm Chích Ma Túy Nhiễm HIV Tại Hà Nội Năm 2016

    PubMed Central

    Thúy, Đào Thị Diệu; Hoàng, Trần Minh; Thúy, Đinh Thanh; Mai, Phạm Phương; Giang, Lê Minh

    2018-01-01

    Đa số người tiêm chích ma túy ở Việt Nam đang sống cùng gia đình và điều này tạo ra gánh nặng không nhỏ trong việc chăm sóc. Mục tiêu nghiên cứu là mô tả đặc điểm trầm cảm ở thành viên gia đình của nam tiêm chích ma túy nhiễm HIV và một số yếu tố liên quan. Số liệu nghiên cứu cắt ngang thu thập từ 138 người là thành viên gia đình của nam tiêm chích ma túy nhiễm HIV tại Hà Nội. Kết quả nghiên cứu cho thấy có xấp xỉ 20% mẫu nghiên cứu có dấu hiệu trầm cảm ở mức độ từ nhẹ đến rất nặng. Gánh nặng chăm sóc và mối quan hệ gia đình có liên quan với trầm cảm ở thành viên gia đình. Nghiên cứu cho thấy nhu cầu can thiệp để cải thiện mối quan hệ gia đình, giảm bớt gánh nặng chăm sóc nhằm nâng cao sức khỏe tinh thần ở thành viên gia đình người tiêm chích ma túy nhiễm HIV. PMID:29367942

  5. Statistical analysis of global horizontal solar irradiation GHI in Fez city, Morocco

    NASA Astrophysics Data System (ADS)

    Bounoua, Z.; Mechaqrane, A.

    2018-05-01

    An accurate knowledge of the solar energy reaching the ground is necessary for sizing and optimizing the performances of solar installations. This paper describes a statistical analysis of the global horizontal solar irradiation (GHI) at Fez city, Morocco. For better reliability, we have first applied a set of check procedures to test the quality of hourly GHI measurements. We then eliminate the erroneous values which are generally due to measurement or the cosine effect errors. Statistical analysis show that the annual mean daily values of GHI is of approximately 5 kWh/m²/day. Daily monthly mean values and other parameter are also calculated.

  6. Identification of periods of clear sky irradiance in time series of GHI measurements

    DOE PAGES

    Reno, Matthew J.; Hansen, Clifford W.

    2016-01-18

    In this study, we present a simple algorithm for identifying periods of time with broadband global horizontal irradiance (GHI) similar to that occurring during clear sky conditions from a time series of GHI measurements. Other available methods to identify these periods do so by identifying periods with clear sky conditions using additional measurements, such as direct or diffuse irradiance. Our algorithm compares characteristics of the time series of measured GHI with the output of a clear sky model without requiring additional measurements. We validate our algorithm using data from several locations by comparing our results with those obtained from amore » clear sky detection algorithm, and with satellite and ground-based sky imagery.« less

  7. Identification of periods of clear sky irradiance in time series of GHI measurements

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

    Reno, Matthew J.; Hansen, Clifford W.

    In this study, we present a simple algorithm for identifying periods of time with broadband global horizontal irradiance (GHI) similar to that occurring during clear sky conditions from a time series of GHI measurements. Other available methods to identify these periods do so by identifying periods with clear sky conditions using additional measurements, such as direct or diffuse irradiance. Our algorithm compares characteristics of the time series of measured GHI with the output of a clear sky model without requiring additional measurements. We validate our algorithm using data from several locations by comparing our results with those obtained from amore » clear sky detection algorithm, and with satellite and ground-based sky imagery.« less

  8. GHI calculation sensitivity on microphysics, land- and cumulus parameterization in WRF over the Reunion Island

    NASA Astrophysics Data System (ADS)

    De Meij, A.; Vinuesa, J.-F.; Maupas, V.

    2018-05-01

    The sensitivity of different microphysics and dynamics schemes on calculated global horizontal irradiation (GHI) values in the Weather Research Forecasting (WRF) model is studied. 13 sensitivity simulations were performed for which the microphysics, cumulus parameterization schemes and land surface models were changed. Firstly we evaluated the model's performance by comparing calculated GHI values for the Base Case with observations for the Reunion Island for 2014. In general, the model calculates the largest bias during the austral summer. This indicates that the model is less accurate in timing the formation and dissipation of clouds during the summer, when higher water vapor quantities are present in the atmosphere than during the austral winter. Secondly, the model sensitivity on changing the microphysics, cumulus parameterization and land surface models on calculated GHI values is evaluated. The sensitivity simulations showed that changing the microphysics from the Thompson scheme (or Single-Moment 6-class scheme) to the Morrison double-moment scheme, the relative bias improves from 45% to 10%. The underlying reason for this improvement is that the Morrison double-moment scheme predicts the mass and number concentrations of five hydrometeors, which help to improve the calculation of the densities, size and lifetime of the cloud droplets. While the single moment schemes only predicts the mass for less hydrometeors. Changing the cumulus parameterization schemes and land surface models does not have a large impact on GHI calculations.

  9. DOCKING OF STRUCTURALLY RELATED DIOLEPOXIDES OF BENZO(GHI)FLUORANTHENE WITH DNA

    EPA Science Inventory

    Docking of structurally-related diolepoxides of benzo{ghi}fluoranthene and benzo{c}phenanthrene with DNA
    Polycyclic aromatic hydrocarbons are a class of chemicals found in the environment. Some class members are potent carcinogens while others with similar structures show litt...

  10. NAM Products

    Science.gov Websites

    Available NAM 218 AWIPS Grid - CONUS (12-km Resolution; full complement of pressure level fields and some ; full complement of surface-based fields) Filename Inventory nam.tccz.awip12fh.tm00.grib2 FH00 FH01 fh.xxxx_tl.press_gr.grbgrd NAM 242 AWIPS Grid - Over Alaska (11.25 KM Resolution; full complement of pressure level fields

  11. Index of /data/nccf/com/nam/prod

    Science.gov Websites

    -2018 21:04 - nam.20180521/ 21-May-2018 21:03 - nam.20180522/ 22-May-2018 21:02 - nam.20180523/ 23-May -2018 21:04 - nam.20180524/ 24-May-2018 21:02 - nam.20180525/ 25-May-2018 21:04 - nam.20180526/ 26-May -2018 21:03 - nam.20180527/ 27-May-2018 11:51 - nam_mos.20180526/ 26-May-2018 14:55 - nam_mos.20180527

  12. Researching the Viet Nam War inside Viet Nam: U.S. Student Teachers Explore War Myths

    ERIC Educational Resources Information Center

    Vadas, Robert E.

    2007-01-01

    The author asserts that it is time for social studies teachers to engage students in a review of the rift between historical reality and mythology about Viet Nam, especially in light of recent comparisons that many have made between the Viet Nam War and the current situation in Iraq. Few teachers dealt with Viet Nam at the time of the war, and…

  13. Neutrophil activator of matrix metalloproteinase-2 (NAM).

    PubMed

    Rollo, Ellen E; Hymowitz, Michelle; Schmidt, Cathleen E; Montana, Steve; Foda, Hussein; Zucker, Stanley

    2006-01-01

    We have isolated a novel soluble factor(s), neutrophil activator of matrix metalloproteinases (NAM), secreted by unstimulated normal human peripheral blood neutrophils that causes the activation of cell secreted promatrix metalloproteinase-2 (proMMP-2). Partially purified preparations of NAM have been isolated from the conditioned media of neutrophils employing gelatin-Sepharose chromatography and differential membrane filter centrifugation. NAM activity, as assessed by exposing primary human umbilical vein endothelial cells (HUVEC) or HT1080 cells to NAM followed by gelatin zymography, was seen within one hour. Tissue inhibitor of metalloproteinase-2 (TIMP-2) and hydroxamic acid derived inhibitors of MMPs (CT1746 and BB94) abrogated the activation of proMMP-2 by NAM, while inhibitors of serine and cysteine proteases showed no effect. NAM also produced an increase in TIMP-2 binding to HUVEC and HT1080 cell surfaces that was inhibited by TIMP-2, CT1746, and BB94. Time-dependent increases in MT1-MMP protein and mRNA were seen following the addition of NAM to cells. These data support a role for NAM in cancer dissemination.

  14. Inventory of NAM Files on NOMADS

    Science.gov Websites

    Inventory of NAM Files on NOMADS GRIB Filter options Description Filename Cycles Available 12km nam.tCCz.priconest.hiresfFF.tm00.grib2 00,06,12,18 UTC OPeNDAP options Description Filename Cycles Available Hourly nam1hr_CCz

  15. The Pseudomonas aeruginosa efflux pump MexGHI-OpmD transports a natural phenazine that controls gene expression and biofilm development

    PubMed Central

    Sakhtah, Hassan; Koyama, Leslie; Zhang, Yihan; Morales, Diana K.; Fields, Blanche L.; Price-Whelan, Alexa; Hogan, Deborah A.; Shepard, Kenneth; Dietrich, Lars E. P.

    2016-01-01

    Redox-cycling compounds, including endogenously produced phenazine antibiotics, induce expression of the efflux pump MexGHI-OpmD in the opportunistic pathogen Pseudomonas aeruginosa. Previous studies of P. aeruginosa virulence, physiology, and biofilm development have focused on the blue phenazine pyocyanin and the yellow phenazine-1-carboxylic acid (PCA). In P. aeruginosa phenazine biosynthesis, conversion of PCA to pyocyanin is presumed to proceed through the intermediate 5-methylphenazine-1-carboxylate (5-Me-PCA), a reactive compound that has eluded detection in most laboratory samples. Here, we apply electrochemical methods to directly detect 5-Me-PCA and find that it is transported by MexGHI-OpmD in P. aeruginosa strain PA14 planktonic and biofilm cells. We also show that 5-Me-PCA is sufficient to fully induce MexGHI-OpmD expression and that it is required for wild-type colony biofilm morphogenesis. These physiological effects are consistent with the high redox potential of 5-Me-PCA, which distinguishes it from other well-studied P. aeruginosa phenazines. Our observations highlight the importance of this compound, which was previously overlooked due to the challenges associated with its detection, in the context of P. aeruginosa gene expression and multicellular behavior. This study constitutes a unique demonstration of efflux-based self-resistance, controlled by a simple circuit, in a Gram-negative pathogen. PMID:27274079

  16. NAM - Eta to NMM conversion 20060613

    Science.gov Websites

    North American Mesoscale (NAM) time slot. Currently the the Eta forecast model is used for the NAM, but Eta and its output will be available at the same time. There will be some minor addition of products MB per file (time step). - The following fields will be added: - omega @ 10, 20, & 30 mb - height

  17. Viet Nam -- attractive plays in a new geological province

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

    Canh, T.; Ha, D.V.; Carstens, H.

    1994-03-14

    Vietnam Oil and Gas Corp. (Petrovietnam) has, through 1993 and since the Vietnamese government first declared its new open door policy more than 6 years ago, issued 27 production sharing contracts to Asian, Australian, European, and North American companies. The most prospective part of Viet Nam's shallow water acreage is now being explored intensely. This acreage is concentrated in the Nam Con Son basin, the Cuu Long basin (previously known as the Mekong basin), the Malay-Thochusia basin (all off southern Viet Nam) and the Quang Ngai graben, the Song Hong basin, and the Red River delta (all off northern Vietmore » Nam). With 6.3 million metric tons of crude oil pumped in 1993 from White Tiger (Bach Ho) field, and with Dragon (Rong) and Big Bear (Dai Hung) fields soon to be brought on stream, offshore Viet Nam is considered to be very attractive by the international oil industry, and the country's potential is still far from being fully appraised. The paper describes the exploration history of Viet Nam, sedimentary basins, play types, source rocks, and terms and conditions of licensing.« less

  18. British firms mark progress off Viet Nam

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

    Not Available

    1992-11-23

    British companies are making more inroads in exploring for oil and gas off Viet Nam. British Gas plc won a 25 year production sharing contract for a license off southern Viet Nam in the South China Sea. Meantime, London independent Lasmo plc started seismic surveys on the block adjoining the British Gas block. Separately, Thailand and Viet Nam have reached agreement to jointly explore for and develop oil and gas found in waters claimed by both countries. Plans call for the two countries to draw up joint development plans covering oil and gas resources in the southeastern fringe of themore » Gulf of Thailand. Bangkok officials say they would have preferred to delineate maritime boundaries with Hanoi, but opted for the joint development accord, noting that Thailand and Malaysia had taken 12 years to resolve a similar dispute.« less

  19. Verify MesoNAM Performance

    NASA Technical Reports Server (NTRS)

    Bauman, William H., III

    2010-01-01

    The AMU conducted an objective analysis of the MesoNAM forecasts compared to observed values from sensors at specified KSC/CCAFS wind towers by calculating the following statistics to verify the performance of the model: 1) Bias (mean difference), 2) Standard deviation of Bias, 3) Root Mean Square Error (RMSE), and 4) Hypothesis test for Bias = O. The 45 WS LWOs use the MesoNAM to support launch weather operations. However, the actual performance of the model at KSC and CCAFS had not been measured objectively. The analysis compared the MesoNAM forecast winds, temperature and dew point to the observed values from the sensors on wind towers. The data were stratified by tower sensor, month and onshore/offshore wind direction based on the orientation of the coastline to each tower's location. The model's performance statistics were then calculated for each wind tower based on sensor height and model initialization time. The period of record for the data used in this task was based on the operational start of the current MesoNAM in mid-August 2006 and so the task began with the first full month of data, September 2006, through May 2010. The analysis of model performance indicated: a) The accuracy decreased as the forecast valid time from the model initialization increased, b) There was a diurnal signal in T with a cool bias during the late night and a warm bias during the afternoon, c) There was a diurnal signal in Td with a low bias during the afternoon and a high bias during the late night, and d) The model parameters at each vertical level most closely matched the observed parameters at heights closest to those vertical levels. The AMU developed a GUI that consists of a multi-level drop-down menu written in JavaScript embedded within the HTML code. This tool allows the LWO to easily and efficiently navigate among the charts and spreadsheet files containing the model performance statistics. The objective statistics give the LWOs knowledge of the model's strengths and

  20. Enterovirus D68 in Viet Nam (2009-2015).

    PubMed

    Ny, Nguyen Thi Han; Anh, Nguyen To; Hang, Vu Thi Ty; Nguyet, Lam Anh; Thanh, Tran Tan; Ha, Do Quang; Minh, Ngo Ngoc Quang; Ha, Do Lien Anh; McBride, Angela; Tuan, Ha Manh; Baker, Stephen; Tam, Pham Thi Thanh; Phuc, Tran My; Huong, Dang Thao; Loi, Tran Quoc; Vu, Nguyen Tran Anh; Hung, Nguyen Van; Minh, Tran Thi Thuy; Xang, Nguyen Van; Dong, Nguyen; Nghia, Ho Dang Trung; Chau, Nguyen Van Vinh; Thwaites, Guy; van Doorn, H Rogier; Anscombe, Catherine; Le Van, Tan

    2017-01-01

    Since 1962, enterovirus D68 (EV-D68) has been implicated in multiple outbreaks and sporadic cases of respiratory infection worldwide, but especially in the USA and Europe with an increasing frequency between 2010 and 2014. We describe the detection, associated clinical features and molecular characterization of EV-D68 in central and southern Viet Nam between 2009 and 2015. Enterovirus/rhinovirus PCR positive respiratory or CSF samples taken from children and adults with respiratory/central nervous system infections in Viet Nam were tested by an EV-D68 specific PCR. The included samples were derived from 3 different observational studies conducted at referral hospitals across central and southern Viet Nam between 2009 and 2015. Whole-genome sequencing was carried out using a MiSeq based approach. Phylogenetic reconstruction and estimation of evolutionary rate and recombination were carried out in BEAST and Recombination Detection Program, respectively. EV-D68 was detected in 21/625 (3.4%) enterovirus/rhinovirus PCR positive respiratory samples but in none of the 15 CSF. All the EV-D68 patients were young children (age range: 11.8 - 24.5 months) and had moderate respiratory infections. Phylogenetic analysis suggested that the Vietnamese sequences clustered with those from Asian countries, of which 9 fell in the B1 clade, and the remaining sequence was identified within the A2 clade. One intra sub-clade recombination event was detected, representing the second reported recombination within EV-D68. The evolutionary rate of EV-D68 was estimated to be 5.12E -3 substitutions/site/year. Phylogenetic analysis indicated that the virus was imported into Viet Nam in 2008. We have demonstrated for the first time EV-D68 has been circulating at low levels in Viet Nam since 2008, associated with moderate acute respiratory infection in children. EV-D68 in Viet Nam is most closely related to Asian viruses, and clusters separately from recent US and European viruses that were

  1. Evaluation of NOAA's High Resolution Rapid Refresh (HRRR), 12 km North America Model (NAM12) and 4km North America Model (NAM 4) hub-height wind speed forecasts

    NASA Astrophysics Data System (ADS)

    Pendergrass, W.; Vogel, C. A.

    2013-12-01

    As an outcome of discussions between Duke Energy Generation and NOAA/ARL following the 2009 AMS Summer Community Meeting, in Norman Oklahoma, ARL and Duke Energy Generation (Duke) signed a Cooperative Research and Development Agreement (CRADA) which allows NOAA to conduct atmospheric boundary layer (ABL) research using Duke renewable energy sites as research testbeds. One aspect of this research has been the evaluation of forecast hub-height winds from three NOAA atmospheric models. Forecasts of 10m (surface) and 80m (hub-height) wind speeds from (1) NOAA/GSD's High Resolution Rapid Refresh (HRRR) model, (2) NOAA/NCEP's 12 km North America Model (NAM12) and (3) NOAA/NCEP's 4k high resolution North America Model (NAM4) were evaluated against 18 months of surface-layer wind observations collected at the joint NOAA/Duke Energy research station located at Duke Energy's West Texas Ocotillo wind farm over the period April 2011 through October 2012. HRRR, NAM12 and NAM4 10m wind speed forecasts were compared with 10m level wind speed observations measured on the NOAA/ATDD flux-tower. Hub-height (80m) HRRR , NAM12 and NAM4 forecast wind speeds were evaluated against the 80m operational PMM27-28 meteorological tower supporting the Ocotillo wind farm. For each HRRR update, eight forecast hours (hour 01, 02, 03, 05, 07, 10, 12, 15) plus the initialization hour (hour 00), evaluated. For the NAM12 and NAM4 models forecast hours 00-24 from the 06z initialization were evaluated. Performance measures or skill score based on absolute error 50% cumulative probability were calculated for each forecast hour. HRRR forecast hour 01 provided the best skill score with an absolute wind speed error within 0.8 m/s of observed 10m wind speed and 1.25 m/s for hub-height wind speed at the designated 50% cumulative probability. For both NAM4 and NAM12 models, skill scores were diurnal with comparable best scores observed during the day of 0.7 m/s of observed 10m wind speed and 1.1 m/s for hub

  2. Viet Nam steps up offshore E and D push

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

    Not Available

    1992-06-22

    This paper reports on Viet Nam's offshore exploration and development. Hanoi tentatively awarded three of five remaining blocks of prime offshore South China Sea acreage to companies from Europe and the Far East, with a fourth such award reported imminent. And state owned Petrovietnam signed a production sharing contract (PSC) covering acreage in the same area to a combine of British Petroleum Co. plc and Norway's Den norske stats oljeselskap AS. Retention of one block in the area covered by Viet Nam's second bidding round fueled speculation Hanoi is holding it in reserve for U.S. companies to enter bidding, pendingmore » easing of U.S. trade sanctions against Viet Nam, Agence France France (AFP) reported. Second round blocks have been carved from a concession held by Vietsovpetro, a joint venture of Petrovietnam and the former Soviet Union. All are in the southern Con Sun basin of the South China Sea off the port of Vung Tao and on trend with Viet Nam's only producing oil fields.« less

  3. Genetic characterization of the soybean Nested Association Mapping (NAM) population

    USDA-ARS?s Scientific Manuscript database

    A population of nested association mapping (NAM) families can be a valuable resource to a research community. A set of NAM families were developed by crossing 40 diverse soybean genotypes to the common hub cultivar IA 3023. The 41 parents were sequenced with next generation sequencing for single nuc...

  4. Brain MR image segmentation using NAMS in pseudo-color.

    PubMed

    Li, Hua; Chen, Chuanbo; Fang, Shaohong; Zhao, Shengrong

    2017-12-01

    Image segmentation plays a crucial role in various biomedical applications. In general, the segmentation of brain Magnetic Resonance (MR) images is mainly used to represent the image with several homogeneous regions instead of pixels for surgical analyzing and planning. This paper proposes a new approach for segmenting MR brain images by using pseudo-color based segmentation with Non-symmetry and Anti-packing Model with Squares (NAMS). First of all, the NAMS model is presented. The model can represent the image with sub-patterns to keep the image content and largely reduce the data redundancy. Second, the key idea is proposed that convert the original gray-scale brain MR image into a pseudo-colored image and then segment the pseudo-colored image with NAMS model. The pseudo-colored image can enhance the color contrast in different tissues in brain MR images, which can improve the precision of segmentation as well as directly visual perceptional distinction. Experimental results indicate that compared with other brain MR image segmentation methods, the proposed NAMS based pseudo-color segmentation method performs more excellent in not only segmenting precisely but also saving storage.

  5. Viet Nam, once isolated, poised for significant role in oil and gas

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

    Not Available

    1991-07-15

    This paper reports that Viet Nam is on its way up in the petroleum world. After years of international isolation, the country is poised for a flurry of exploration by international oil companies in the early 1990s. Viet Nam has joined the Soviet Union as the only members of the now dissolved, formerly Moscow dominated, 10 nation Council for Mutual Economic Assistance (CMEA) that are self-sufficient in oil production. Moreover, Viet Nam has far outstripped neighboring China, which was not a CMEA member, in offshore oil flow even though China has a much larger Outer Continental Shelf. Prospects are thatmore » Viet Nam will continue to lead China in offshore oil production until 1995 at least.« less

  6. Combiner L'Education Et Le Travail; Experiences en Asie et en Oceanie: Viet Nam (Combining Education and Work; Experiences in Asia and Oceania: Viet Nam).

    ERIC Educational Resources Information Center

    Vien, Hguyen Khac

    Educational policy in Viet Nam has closely followed the revolutionary movement. In the essentially democratic period from 1945 to 1960, Viet Nam created a nationwide 10-grade school system and fought illiteracy on a large scale. By 1960, as socialism began to predominate, especially in the North, traditional educational methods and values began to…

  7. Costs of providing tuberculosis diagnosis and treatment services in Viet Nam.

    PubMed

    Minh, H V; Mai, V Q; Nhung, N V; Hoi, L V; Giang, K B; Chung, L H; Kien, V D; Duyen, N T; Ngoc, N B; Anh, T T; Phuong, T B; Ngan, T T; Khanh, P H

    2017-09-01

    To estimate the cost of providing tuberculosis (TB) diagnosis and treatment packages at different levels of health facilities in Viet Nam. This was a retrospective costing study from the providers' perspective using a standard costing approach. We included typical services for TB diagnosis and treatment based on standard protocols. The least expensive TB service was the 6-month isoniazid preventive therapy regimen for latent tuberculous infection provided by district health centres (US$7.20-14.30, accounting for 0.3-0.7% of Viet Nam's per capita gross domestic product [GDP] of US$2052.30 in 2014). The cost of diagnosing and treating a patient with drug-susceptible TB (the most common type of TB) ranged between US$51.20 and US$180.70, and represented 2.5-8.8% of Viet Nam's per capita GDP in 2014. The most expensive TB service was the diagnosis and treatment of a multidrug-resistant TB case (US$1568.20-2391.20), accounting for 76.4-116.5% of Viet Nam's per capita GDP in 2014). The cost of TB diagnosis and treatment services in Viet Nam varied according to level of health facility, type of TB, different costing options, and different staff cost scenarios.

  8. Characterisation of Mycobacterium tuberculosis isolates lacking IS6110 in Viet Nam.

    PubMed

    Huyen, M N T; Tiemersma, E W; Kremer, K; de Haas, P; Lan, N T N; Buu, T N; Sola, C; Cobelens, F G J; van Soolingen, D

    2013-11-01

    The molecular diagnosis of tuberculosis (TB) in Viet Nam is often based on the detection of insertion sequence (IS) 6110 in Mycobacterium tuberculosis. However, 8-11% of M. tuberculosis strains in South-East Asia do not contain this target and this undermines the validity of these molecular tests. We quantified the frequency of M. tuberculosis strains lacking IS6110 in rural Viet Nam and studied their epidemiological and clinical characteristics. Consecutively diagnosed adult TB patients in rural Southern Viet Nam submitted two sputum samples for culture, IS6110 restriction fragment length polymorphism (RFLP) spoligotyping and 15-loci variable number tandem repeat typing. Polymerase chain reaction (PCR) was performed to confirm the absence of IS6110 elements in strains lacking IS6110 hybridisation in RFLP. Among 2664 TB patient isolates examined, 109 (4.1%) had no IS6110 element. Compared to other strains, these no-copy strains were less often resistant to anti-tuberculosis drugs, particularly to streptomycin (adjusted OR 0.2, 95%CI 0.1-0.5), and showed significant geographic variation. No associations with TB history or demographic factors were found. Strains without the IS6110 target pose a problem in Viet Nam as regards false-negative molecular TB diagnosis in PCR. Compared to other strains circulating in Viet Nam, no-copy strains are more susceptible to anti-tuberculosis drugs.

  9. Benzo[ghi]perylene activates the AHR pathway to exert biological effects on the NL-20 human bronchial cell line.

    PubMed

    Zaragoza-Ojeda, Montserrat; Eguía-Aguilar, Pilar; Perezpeña-Díazconti, Mario; Arenas-Huertero, Francisco

    2016-08-10

    Polycyclic aromatic hydrocarbons (PAH) are produced by incomplete combustion of organic material. In the Mexico City atmosphere, the most abundant PAH is benzo[ghi]perylene (BghiP), a gasoline combustion marker. At present, there are no reports of the effects of BghiP on human bronchial cells, so the aim of the study was to evaluate the effects in vitro of BghiP on the NL-20 cell line. Results showed that BghiP induced the formation of small vesicles throughout the cytoplasm, with absence of nuclear fragmentation. At 48h exposition, damage in cell membrane increased significantly at 1.24μg/mL of BghiP (p<0.05). Immunocytochemistry revealed that BghiP provokes nuclear translocation of AhR receptor, which indicates that this compound can induce transcription of genes via receptor binding (AhR pathway activation). BghiP induced a two-fold increase (p<0.05) in the expression of AhR and CYP4B1 (a lung-specific pathway effector). In the presence of the receptor antagonist CH-223191, the loss of viability, the nuclear translocation and the overexpression of genes decreased, though this did not prevent the formation of vesicles. BghiP induced oxidative stress and in presence of the receptor antagonist this increased significantly. In conclusion, BghiP can activate the overexpression of AhR and CYP4B1, and the effects are abated by the AhR receptor antagonist. This is the first report to prove that BghiP utilizes the AhR pathway to exert its toxic effects on the NL-20 human bronchial cell line . Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  10. 31 CFR 500.560 - Bank accounts of official representatives of foreign governments in North Korea, North Viet-Nam...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... representatives of foreign governments in North Korea, North Viet-Nam, Cambodia, or South Viet-Nam. 500.560... governments in North Korea, North Viet-Nam, Cambodia, or South Viet-Nam. Specific licenses are issued authorizing payments from accounts of official representatives of foreign governments in North Korea, North...

  11. Educating the educators at Hue Medical College, Hue, Viet Nam.

    PubMed

    Pron, A L; Zygmont, D; Bender, P; Black, K

    2008-06-01

    In June 2005, four faculty members from Temple University, Philadelphia, USA, conducted a nursing educator workshop in Hue, Viet Nam. Didactic and clinical instruction addressed paediatric, maternity, psychiatric and surgical nursing content as well as instructional methods and student evaluation techniques. This educator workshop was requested as means of increasing the professionalization of nursing in Viet Nam. Student nurses in Viet Nam are taught by physician-faculty. Between the cultural and economic factors that contribute to the current status and practice of nursing in Viet Nam and the lack of nurse educator role models, the nursing profession has many obstacles to overcome in their quest for increased autonomy. During the workshop, in addition to modelling interactive teaching methods as they taught the classroom and clinical content, these authors also demonstrated the level of knowledge expected of nurses in the USA. Despite much advance planning for this workshop, there were many challenges for the USA faculty. Some of the lessons learned which might help others included having a sense of humour, maintaining flexibility in teaching styles and content, being prepared for the cultural and religious influences on health care, and utilizing all of one's nursing skills to find creative solutions when teaching nursing in another country.

  12. Time to unsuccessful tuberculosis treatment outcome, Cambodia, China, and Viet Nam.

    PubMed

    Hoa, N B; Sokun, C; Wei, C; Lauritsen, J M; Rieder, H L

    2012-03-21

    To determine the frequency and characteristics of patients with unsuccessful tuberculosis (TB) treatment. Random selection of TB case registers among all treatment units in Cambodia, two provinces in China, and Viet Nam. The data of two calendar years were analyzed to assess unsuccessful outcomes and their time of occurrence. Among the 33 309 TB patients, treatment was unsuccessful in respectively 10.1%, 3.0% and 9.1% of patients in Cambodia, China and Viet Nam. The risk of death was highest in Cambodia, higher among males than females, increased with age, and was more common among retreatment cases than new cases, and among patients with a high than a low sputum smear microscopy grade. Half of all deaths occurred in the first 2 months in Cambodia and within 11 weeks in China and Viet Nam. Median time to default was 3 months in Cambodia and Viet Nam, and about 2 months in China. Treatment was highly successful in the three study countries, with a low proportion of death and default. As the majority of defaulting occurs at the beginning of treatment, all countries should critically review their current policy of treatment support in this period.

  13. Recent increase in sex ratio at birth in Viet Nam.

    PubMed

    Guilmoto, Christophe Z; Hoàng, Xuyên; Van, Toan Ngo

    2009-01-01

    Since the 1980s, sex ratio at birth (male births per 100 female births) has increased in many Asian countries as a result of selective abortions, but to date there has been no such evidence for Viet Nam. Our aim in this paper is to ascertain the situation with respect to sex ratio at birth in Viet Nam over the past five years. Original data were obtained from sample population surveys in Viet Nam recording annual birth rates since 2000 of about 450,000 women, as well as from two successive birth surveys conducted for the first time in 2007 (1.1 million births). The annual population surveys include specific information on birth history and mothers' characteristics to be used for the analysis of trends and differentials in sex ratio at birth. Birth history statistics indicate that the SRB in Viet Nam has recorded a steady growth since 2001. Starting from a level probably close to the biological standard of 105, the SRB reached 108 in 2005 and 112 in 2006, a value significantly above the normal level. An independent confirmation of these results comes from the surveys of births in health facilities which yielded a SRB of 110 in 2006-07. High SRB is linked to various factors such as access to modern health care, number of prenatal visits, level of higher education and employment status, young age, province of residence and prenatal sex determination. These results suggest that prenatal sex determination followed by selective abortion has recently become more common in Viet Nam. This recent trend is a consequence of various factors such as preference for sons, declining fertility, easy access to abortion, economic development as well as the increased availability of ultrasonography facilities.

  14. Tuberculosis case notification data in Viet Nam, 2007 to 2012.

    PubMed

    Nhung, Nguyen Viet; Hoa, Nguyen Binh; Khanh, Pham Huyen; Hennig, Cornelia

    2015-01-01

    Tuberculosis (TB) remains a major cause of morbidity and mortality, and Viet Nam ranks 12 among the 22 high-TB burden countries. This study analyses surveillance data of the National Tuberculosis Control Programme in Viet Nam for the six-year period 2007 to 2012. During the study period, 598,877 TB cases (all forms) were notified, and 313,225 (52.3%) were new smear-positive cases. The case notification rate of new smear-positive cases was decreased, from 65 per 100,000 population in 2007 to 57 per 100,000 population in 2012; this decrease was observed for males and females in all age groups except males aged 0-14 and females aged 15-24 years. The male-to-female ratio of new smear-positive TB cases increased from 2.85 in 2007 to 3.02 in 2012. The average annual cure rate of new smear-positive cases was 90.3%. The high male-to-female ratio for new smear-positive TB cases in this notification data was lower than that from the 2007 TB prevalence survey in Viet Nam, suggesting a lower case detection for males. The decrease in new smear-positive case notification rates may reflect a decline in TB incidence in Viet Nam as several programmatic improvements have been made, although further research is required to increase case detection among young males and children.

  15. MesoNAM Verification Phase II

    NASA Technical Reports Server (NTRS)

    Watson, Leela R.

    2011-01-01

    The 45th Weather Squadron Launch Weather Officers use the 12-km resolution North American Mesoscale model (MesoNAM) forecasts to support launch weather operations. In Phase I, the performance of the model at KSC/CCAFS was measured objectively by conducting a detailed statistical analysis of model output compared to observed values. The objective analysis compared the MesoNAM forecast winds, temperature, and dew point to the observed values from the sensors in the KSC/CCAFS wind tower network. In Phase II, the AMU modified the current tool by adding an additional 15 months of model output to the database and recalculating the verification statistics. The bias, standard deviation of bias, Root Mean Square Error, and Hypothesis test for bias were calculated to verify the performance of the model. The results indicated that the accuracy decreased as the forecast progressed, there was a diurnal signal in temperature with a cool bias during the late night and a warm bias during the afternoon, and there was a diurnal signal in dewpoint temperature with a low bias during the afternoon and a high bias during the late night.

  16. Time to unsuccessful tuberculosis treatment outcome, Cambodia, China, and Viet Nam

    PubMed Central

    Sokun, C.; Wei, C.; Lauritsen, J. M.; Rieder, H. L.

    2012-01-01

    Objective: To determine the frequency and characteristics of patients with unsuccessful tuberculosis (TB) treatment. Methods: Random selection of TB case registers among all treatment units in Cambodia, two provinces in China, and Viet Nam. The data of two calendar years were analyzed to assess unsuccessful outcomes and their time of occurrence. Results: Among the 33 309 TB patients, treatment was unsuccessful in respectively 10.1%, 3.0% and 9.1% of patients in Cambodia, China and Viet Nam. The risk of death was highest in Cambodia, higher among males than females, increased with age, and was more common among retreatment cases than new cases, and among patients with a high than a low sputum smear microscopy grade. Half of all deaths occurred in the first 2 months in Cambodia and within 11 weeks in China and Viet Nam. Median time to default was 3 months in Cambodia and Viet Nam, and about 2 months in China. Conclusions: Treatment was highly successful in the three study countries, with a low proportion of death and default. As the majority of defaulting occurs at the beginning of treatment, all countries should critically review their current policy of treatment support in this period. PMID:26392939

  17. Tuberculosis case notification data in Viet Nam, 2007 to 2012

    PubMed Central

    Nhung, Nguyen Viet; Khanh, Pham Huyen; Hennig, Cornelia

    2015-01-01

    Tuberculosis (TB) remains a major cause of morbidity and mortality, and Viet Nam ranks 12 among the 22 high-TB burden countries. This study analyses surveillance data of the National Tuberculosis Control Programme in Viet Nam for the six-year period 2007 to 2012. During the study period, 598 877 TB cases (all forms) were notified, and 313 225 (52.3%) were new smear-positive cases. The case notification rate of new smear-positive cases was decreased, from 65 per 100 000 population in 2007 to 57 per 100 000 population in 2012; this decrease was observed for males and females in all age groups except males aged 0–14 and females aged 15–24 years. The male-to-female ratio of new smear-positive TB cases increased from 2.85 in 2007 to 3.02 in 2012. The average annual cure rate of new smear-positive cases was 90.3%. The high male-to-female ratio for new smear-positive TB cases in this notification data was lower than that from the 2007 TB prevalence survey in Viet Nam, suggesting a lower case detection for males. The decrease in new smear-positive case notification rates may reflect a decline in TB incidence in Viet Nam as several programmatic improvements have been made, although further research is required to increase case detection among young males and children. PMID:25960918

  18. Pesticide regulations and farm worker safety: the need to improve pesticide regulations in Viet Nam.

    PubMed

    Phung, Dung Tri; Connell, Des; Miller, Greg; Rutherford, Shannon; Chu, Cordia

    2012-06-01

    Agricultural pesticide use in Viet Nam has more than tripled since 1990. However, pesticide legislation and regulations have not been developed in response to this large increase in usage, as a result of which pesticides pose a serious threat to human health and the environment. This paper identifies the need to improve pesticide regulations in Viet Nam through a comparative analysis of pesticide regulations in Viet Nam and the United States of America, where the rate of acute poisoning among agricultural workers is much lower than in Viet Nam and where information pertaining to pesticide regulations is made accessible to the public. The analysis identified several measures that would help to improve Viet Nam's pesticide regulations. These include enhancing pesticide legislation, clarifying the specific roles and active involvement of both the environmental and health sectors; performing a comprehensive risk-benefit evaluation of pesticide registration and management practices; improving regulations on pesticide suspension and cancellation, transport, storage and disposal; developing import and export policies and enhancing pesticide-related occupational safety programmes.

  19. Walking the Line: Quality Assurance Policy Development and Implementation in Vi?t Nam

    ERIC Educational Resources Information Center

    Madden, Meggan

    2014-01-01

    Although Vi?t Nam's experiences with quality assurance (QA) policy development have been influenced by its relationships with, and funding from, the World Bank and regional organizations, the state-centric values of the Socialist Republic of Vi?t Nam still navigate the implementation process. The development of QA in Vietnamese higher education…

  20. Home From the War: A Study of Psychiatric Problems in Viet Nam Returnees.

    ERIC Educational Resources Information Center

    Strange, Robert E.; Brown, Dudley E., Jr.

    1970-01-01

    Fifty patients who developed psychiatric problems after return from tours of Viet Nam combat duty were compared with a group of patients who had not had such duty. The Viet Nam returnees reported more conflicts in intimate relationships and had a higher incidence of depression and somatization than did the noncombat group. A study was made of…

  1. Phylogeography of Recently Emerged DENV-2 in Southern Viet Nam

    PubMed Central

    Rabaa, Maia A.; Ty Hang, Vu Thi; Wills, Bridget; Farrar, Jeremy; Simmons, Cameron P.; Holmes, Edward C.

    2010-01-01

    Revealing the dispersal of dengue viruses (DENV) in time and space is central to understanding their epidemiology. However, the processes that shape DENV transmission patterns at the scale of local populations are not well understood, particularly the impact of such factors as human population movement and urbanization. Herein, we investigated trends in the spatial dynamics of DENV-2 transmission in the highly endemic setting of southern Viet Nam. Through a phylogeographic analysis of 168 full-length DENV-2 genome sequences obtained from hospitalized dengue cases from 10 provinces in southern Viet Nam, we reveal substantial genetic diversity in both urban and rural areas, with multiple lineages identified in individual provinces within a single season, and indicative of frequent viral migration among communities. Focusing on the recently introduced Asian I genotype, we observed particularly high rates of viral exchange between adjacent geographic areas, and between Ho Chi Minh City, the primary urban center of this region, and populations across southern Viet Nam. Within Ho Chi Minh City, patterns of DENV movement appear consistent with a gravity model of virus dispersal, with viruses traveling across a gradient of population density. Overall, our analysis suggests that Ho Chi Minh City may act as a source population for the dispersal of DENV across southern Viet Nam, and provides further evidence that urban areas of Southeast Asia play a primary role in DENV transmission. However, these data also indicate that more rural areas are also capable of maintaining virus populations and hence fueling DENV evolution over multiple seasons. PMID:20668540

  2. Phylogeography of recently emerged DENV-2 in southern Viet Nam.

    PubMed

    Rabaa, Maia A; Ty Hang, Vu Thi; Wills, Bridget; Farrar, Jeremy; Simmons, Cameron P; Holmes, Edward C

    2010-07-27

    Revealing the dispersal of dengue viruses (DENV) in time and space is central to understanding their epidemiology. However, the processes that shape DENV transmission patterns at the scale of local populations are not well understood, particularly the impact of such factors as human population movement and urbanization. Herein, we investigated trends in the spatial dynamics of DENV-2 transmission in the highly endemic setting of southern Viet Nam. Through a phylogeographic analysis of 168 full-length DENV-2 genome sequences obtained from hospitalized dengue cases from 10 provinces in southern Viet Nam, we reveal substantial genetic diversity in both urban and rural areas, with multiple lineages identified in individual provinces within a single season, and indicative of frequent viral migration among communities. Focusing on the recently introduced Asian I genotype, we observed particularly high rates of viral exchange between adjacent geographic areas, and between Ho Chi Minh City, the primary urban center of this region, and populations across southern Viet Nam. Within Ho Chi Minh City, patterns of DENV movement appear consistent with a gravity model of virus dispersal, with viruses traveling across a gradient of population density. Overall, our analysis suggests that Ho Chi Minh City may act as a source population for the dispersal of DENV across southern Viet Nam, and provides further evidence that urban areas of Southeast Asia play a primary role in DENV transmission. However, these data also indicate that more rural areas are also capable of maintaining virus populations and hence fueling DENV evolution over multiple seasons.

  3. Gastric and colo-rectal cancer mortality in Viet Nam in the years 2005-2006.

    PubMed

    Ngoan, Le Tran; Anh, Nguyen Thi Diep; Huong, Nguyen Thi Thanh; Thu, Nguyen Thi; Lua, Nguyen Thi; Hang, Lai Thi Minh; Bich, Nguyen Ngoc; Hieu, Nguyen Van; Quyet, Ha Van; Tai, Le Thi; Van, Do Duc; Khan, Nguyen Cong; Mai, Le Bach; Tokudome, Shinkan; Yoshimura, Takesumi

    2008-01-01

    The International Collaborative Epidemiological Study of Host and Environmental Factors for Stomach and Colorectal Cancers in Southeast Asian Countries (SEACs) has been conducted in Viet Nam from 2003 to 2008 on a case-control basis. For further effective primary prevention, we examined gastric and colorectal cancer mortality nationwide in eight regions of Viet Nam in 2005-06. Both demographic data and lists of all deaths in 2005-06 were obtained from all 10,769 commune health stations in Viet Nam. Five indicators included name, age, sex, date of death and cause of death was collected for each case. We selected only communes having the list of deaths with clear cause for each case and crude mortality rate for all causes from 300-600/100,000 as published by the Ministry of Health for a reasonable accuracy and completeness. Obtained data for all causes, all cancers, stomach and colorectal cancer deaths as well as demographic information were processed using Excel software and exported to STATA 8.0 for estimation of world age-standardized cancer mortality rates per 100,000. Data were available for 1,246 gastric cases, (819 male and 427 female) with age-standardized mortality rates from 12.7 to 31.3 per 100,000 in males and from 5.9 to 10.3 per 100,000 in females in the 8 regions of the country. For colorectal cancers, 542 cases (268 male and 274 female) gave mortality rates from 4.0 to 11.3 per 100,000 in males and from 3.0 to 7.8 per 100,000 in females. Stomach cancer mortality in males in the region of North East in the North Viet Nam (2005-06) was higher than that in Japan (2002) (31.3 versus 28.7 per 100,000) while colorectal cancer in Viet Nam was lower. While prevalence of Helicobacter pyloris infection in Viet Nam was from 70-75% in both males and females, the stomach cancer rate in males was significantly higher than in females, 31.3 versus 6.8 per 100,000, suggesting an influence of other environmental risk factors. Whether protective factors are operating

  4. Characteristics of tuberculosis patients at intake in Cambodia, two provinces in China, and Viet Nam.

    PubMed

    Hoa, Nguyen B; Wei, Chen; Sokun, Chay; Lauritsen, Jens M; Rieder, Hans L

    2011-05-23

    The tuberculosis register is a critical data source for the information system of national tuberculosis control programs. From the information in the tuberculosis case register, it is possible to extend the standard analysis of age and sex characteristics among sputum smear-positive cases to all tuberculosis case categories. National tuberculosis programs might utilize such information to identify problems related to referral and access to diagnosis and treatment. Based on the electronic database we created, our objectives were to provide a detailed description of age and sex characteristics of tuberculosis patients at registration and to provide a comparison of age-specific sex characteristics among incident and prevalent sputum smear-positive cases. A representative sample of tuberculosis case registers from 1 January 2003 to 31 December 2005 was selected in Cambodia, two provinces in China and Viet Nam. Age and sex characteristics of cases in the three separate prevalence surveys in the three jurisdictions (Cambodia: year 2002; China: year 2000; and Viet Nam: year 2006-2007) were obtained for comparison. A total 37,635 patients had been registered during the period in the selected units in the three countries. Cases were more frequently male in all three countries with 53%, 71%, and 69% in Cambodia, China, and Viet Nam, respectively.The ratios of the female-to-male odds in the notification system to that in the prevalence survey in smear-positive cases in Cambodia, China and Viet Nam were 2.1, 0.9, and 1.8, respectively. Because of the small proportion of extrapulmonary tuberculosis registered in China, we limited the analysis on age and sex distribution for extrapulmonary cases to Cambodia and Viet Nam. The proportion with extrapulmonary tuberculosis among all cases was 18.5% in Cambodia and 15.7% in Viet Nam, decreasing in frequency with increasing age. Characteristics of patients greatly differed between countries and between patient categories. In Cambodia

  5. Characteristics of tuberculosis patients at intake in Cambodia, two provinces in China, and Viet Nam

    PubMed Central

    2011-01-01

    Background The tuberculosis register is a critical data source for the information system of national tuberculosis control programs. From the information in the tuberculosis case register, it is possible to extend the standard analysis of age and sex characteristics among sputum smear-positive cases to all tuberculosis case categories. National tuberculosis programs might utilize such information to identify problems related to referral and access to diagnosis and treatment. Objectives Based on the electronic database we created, our objectives were to provide a detailed description of age and sex characteristics of tuberculosis patients at registration and to provide a comparison of age-specific sex characteristics among incident and prevalent sputum smear-positive cases. Methods A representative sample of tuberculosis case registers from 1 January 2003 to 31 December 2005 was selected in Cambodia, two provinces in China and Viet Nam. Age and sex characteristics of cases in the three separate prevalence surveys in the three jurisdictions (Cambodia: year 2002; China: year 2000; and Viet Nam: year 2006-2007) were obtained for comparison. Results A total 37,635 patients had been registered during the period in the selected units in the three countries. Cases were more frequently male in all three countries with 53%, 71%, and 69% in Cambodia, China, and Viet Nam, respectively. The ratios of the female-to-male odds in the notification system to that in the prevalence survey in smear-positive cases in Cambodia, China and Viet Nam were 2.1, 0.9, and 1.8, respectively. Because of the small proportion of extrapulmonary tuberculosis registered in China, we limited the analysis on age and sex distribution for extrapulmonary cases to Cambodia and Viet Nam. The proportion with extrapulmonary tuberculosis among all cases was 18.5% in Cambodia and 15.7% in Viet Nam, decreasing in frequency with increasing age. Conclusions Characteristics of patients greatly differed between

  6. Potent L-lactic acid assimilation of the fermentative and heterothallic haploid yeast Saccharomyces cerevisiae NAM34-4C.

    PubMed

    Tomitaka, Masataka; Taguchi, Hisataka; Matsuoka, Masayoshi; Morimura, Shigeru; Kida, Kenji; Akamatsu, Takashi

    2014-01-01

    We screened an industrial thermotolerant Saccharomyces cerevisiae strain, KF7, as a potent lactic-acid-assimilating yeast. Heterothallic haploid strains KF7-5C and KF7-4B were obtained from the tetrads of the homothallic yeast strain KF7. The inefficient sporulation and poor spore viability of the haploid strains were improved by two strategies. The first strategy was as follows: (i) the KF7-5C was crossed with the laboratory strain SH6710; (ii) the progenies were backcrossed with KF7-5C three times; and (iii) the progenies were inbred three times to maintain a genetic background close to that of KF7. The NAM12 diploid between the cross of the resultant two strains, NAM11-9C and NAM11-13A, showed efficient sporulation and exhibited excellent growth in YPD medium (pH 3.5) at 35°C with 1.4-h generation time, indicating thermotolerance and acid tolerance. The second strategy was successive intrastrain crosses. The resultant two strains, KFG4-6B and KFG4-4B, showed excellent mating capacity. A spontaneous mutant of KFG4-6B, KFG4-6BD, showed a high growth rate with a generation time of 1.1 h in YPD medium (pH 3.0) at 35°C. The KFG4-6BD strain produced ascospores, which were crossed with NAM11-2C and its progeny to produce tetrads. These tetrads were crossed with KFG4-4B to produce NAM26-14A and NAM26-15A. The latter strain had a generation time of 1.6 h at 35°C in pH 2.5, thus exhibiting further thermotolerance and acid tolerance. A progeny from a cross of NAM26-14A and NAM26-15A yielded the strain NAM34-4C, which showed potent lactic acid assimilation and high transformation efficiency, better than those of a standard laboratory strain. Copyright © 2013 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

  7. RapidNAM: generative manufacturing approach of nasoalveolar molding devices for presurgical cleft lip and palate treatment.

    PubMed

    Bauer, Franz Xaver; Schönberger, Markus; Gattinger, Johannes; Eblenkamp, Markus; Wintermantel, Erich; Rau, Andrea; Güll, Florian Dieter; Wolff, Klaus-Dietrich; Loeffelbein, Denys J

    2017-08-28

    Nasoalveolar molding (NAM) is an accepted treatment strategy in presurgical cleft therapy. The major drawbacks of the treatment listed in the literature relate to the time of the treatment and the coordination of the required interdisciplinary team of therapists, parents, and patients. To overcome these limitations, we present the automated RapidNAM concept that facilitates the design and manufacturing process of NAM devices, and that allows the virtual modification and subsequent manufacture of the devices in advance, with a growth prediction factor adapted to the patient's natural growth. The RapidNAM concept involves (i) the prediction of three trajectories that envelope the fragmented alveolar segments with the goal to mimic a harmonic arch, (ii) the extrusion from the larger toward the smaller alveolar segment along the envelope curves toward the harmonic upper alveolar arch, and (iii) the generation of the NAM device with a ventilation hole, fixation pin, and fixation points for the nasal stents. A feasibility study for a vector-based approach was successfully conducted for unilateral and bilateral cleft lip and palate (CLP) patients. A comparison of the modified target models with the reference target models showed similar results. For further improvement, the number of landmarks used to modify the models was increased by a curve-based approach.

  8. H partitioning between NAMs in garnet-bearing peridotite at subsolidus conditions

    NASA Astrophysics Data System (ADS)

    Demouchy, S. A.; Shcheka, S.; Denis, C. M. M.; Thoraval, C.

    2017-12-01

    Hydrogen distribution between nominally anhydrous minerals (NAMs) of a garnet-lherzolite under subsolidus conditions has been investigated. Separated NAMs from a garnet-peridotite from Patagonia (Chile) are annealed together (olivine, orthopyroxene, clinopyroxene and garnet) using a piston-cylinder at 3 GPa and 1100 °C using talc-Pyrex cell assembly for 10, 25 and 100 hours. The talc-pyrex assembly provides enough hydrogen in the system to re-equilibrate the hydrogen concentrations at high pressure. The three co-existing nominally anhydrous minerals (NAMs, i.e., olivine, orthopyroxene and clinopyroxene) were successfully analyzed using FTIR. The resulting hydrogen concentrations exceed significantly the initial hydrogen concentration by a factor of 13 for olivine and a factor of 3 for both pyroxenes. Once mineral-specific infrared calibrations are applied, the average concentrations in NAMs are 115±12 ppm wt H2O for olivine, 635±75 ppm wt H2O for orthopyroxene and 1214±137 ppm wt H2O for clinopyroxene, garnet grains are dry. Since local equilibrium seems achieved over time (for 100 hours), the calculated concentration ratios are interpreted as mineral-to-mineral hydrogen partition coefficients (i.e., Nernst `s law) for a garnet-peridotite assemblage. It yields, based on mineral-specific infrared calibrations, Dopx/ol=5±1, Dcpx/ol= 10±2, and Dcpx/opx=1.9±0.4. While Dcpx/opx is in agreement (within error) with previous results from experimental studies and concentration ratios observed in mantle-derived peridotites, the Dpx/ol from this study are significantly lower than the values reported from mantle-derived xenoliths and also at odd with several previous experimental studies where melt and/or hydrous minerals co-exists with NAMs. The results confirm the sensitivity of hydrogen incorporation in olivine regarding the amount of water-derived species (H) in the system and/or the amount of water in the co-existing silicate melt. The results are in agreement with

  9. Actin polymerization drives septation of Listeria monocytogenes namA hydrolase mutants, demonstrating host correction of a bacterial defect.

    PubMed

    Alonzo, Francis; McMullen, P David; Freitag, Nancy E

    2011-04-01

    The Gram-positive bacterial cell wall presents a structural barrier that requires modification for protein secretion and large-molecule transport as well as for bacterial growth and cell division. The Gram-positive bacterium Listeria monocytogenes adjusts cell wall architecture to promote its survival in diverse environments that include soil and the cytosol of mammalian cells. Here we provide evidence for the enzymatic flexibility of the murein hydrolase NamA and demonstrate that bacterial septation defects associated with a loss of NamA are functionally complemented by physical forces associated with actin polymerization within the host cell cytosol. L. monocytogenes ΔnamA mutants formed long bacterial chains during exponential growth in broth culture; however, normal septation could be restored if mutant cells were cocultured with wild-type L. monocytogenes bacteria or by the addition of exogenous NamA. Surprisingly, ΔnamA mutants were not significantly attenuated for virulence in mice despite the pronounced exponential growth septation defect. The physical force of L. monocytogenes-mediated actin polymerization within the cytosol was sufficient to sever ΔnamA mutant intracellular chains and thereby enable the process of bacterial cell-to-cell spread so critical for L. monocytogenes virulence. The inhibition of actin polymerization by cytochalasin D resulted in extended intracellular bacterial chains for which septation was restored following drug removal. Thus, despite the requirement for NamA for the normal septation of exponentially growing L. monocytogenes cells, the hydrolase is essentially dispensable once L. monocytogenes gains access to the host cell cytosol. This phenomenon represents a notable example of eukaryotic host cell complementation of a bacterial defect.

  10. Oseltamivir resistance among influenza viruses: surveillance in northern Viet Nam, 2009-2012.

    PubMed

    Hoang Vu, Mai-Phuong; Nguyen, Co Thach; Nguyen, Le Khanh Hang; Nguyen, Thi Kim Phuong; Le, Quynh Mai

    2013-01-01

    Antiviral resistance has been reported in seasonal influenza A viruses and avian influenza A(H5N1) viruses in Viet Nam, raising concerns about the efficacy of treatment. We analysed specimens from two sources during the period 2009-2012: influenza-positive samples from influenza-like illness patients at sentinel clinics in northern Viet Nam and isolates from patients with confirmed A(H5N1) infections. Pyrosequencing was used to detect mutations: H275Y [for A(H1N1) and A(H5N1)], E119V [for A(H3N2)] and I117V [for A(H5N1)]. A neuraminidase inhibition assay was used to determine the Inhibitory Concentration 50 (IC₅₀) values for all influenza A and B isolates. There were 341 influenza A positive samples identified; influenza A(H1N1)pdm09 was identified most frequently (n = 215). In 2009, oseltamivir resistance was observed in 100% (19 of 19) of seasonal A(H1N1) isolates and 1.4% (3/215) of A(H1N1)pdm09 isolates. This H275Y mutation was not found in influenza subtypes A(H5N1) or A(H3N2) isolates. In Viet Nam, seasonal and A(H5N1) influenza vaccines are not currently available; thus, effective treatment is required. The presence of oseltamivir-resistant viruses is therefore a concern. Active surveillance for oseltamivir resistance among influenza viruses circulating in Viet Nam should be continued.

  11. Atmospheric behaviors of polycyclic aromatic hydrocarbons at a Japanese remote background site, Noto peninsula, from 2004 to 2014

    NASA Astrophysics Data System (ADS)

    Tang, Ning; Hakamata, Mariko; Sato, Kousuke; Okada, Yumi; Yang, Xiaoyang; Tatematsu, Michiya; Toriba, Akira; Kameda, Takayuki; Hayakawa, Kazuichi

    2015-11-01

    Total suspended particulates were collected at a Japanese remote background site (Noto Air Monitoring Station; NAMS) on the Noto Peninsula from September 2004 to June 2014. Nine polycyclic aromatic hydrocarbons (PAHs) in the particulates (fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, benzo[ghi]perylene and indeno[1,2,3-cd]pyrene) were determined by HPLC with fluorescence detection. The mean total concentrations of the nine PAHs in the cold season (November to May for the years 2004-2014) was 670 pg m-3 (range 37-4100 pg m-3). The mean total concentration in the warm season (June to October for the same period) was 170 pg m-3 (range 31-960 pg m-3). The atmospheric PAH level at NAMS decreased in recent years, although no significant change was found in the warm season. An analysis of meteorological conditions showed that the atmospheric PAHs at NAMS were long range transported from Northeast China in the cold seasons and were contributed to by Japanese domestic sources in the warm seasons. Lower concentration ratios of reactive PAHs to their isomers at NAMS also supported these results. Activities associated with the Beijing Olympic and Paralympic Games in 2008 and reconstruction after the 2007 Noto Hanto earthquake may have contributed to the yearly variations of atmospheric PAH levels at NAMS during the period 2007-2009. Source control measures implemented by the Chinese and Japanese governments appear to have been effective in decreasing the atmospheric PAH levels at NAMS in recent years.

  12. Analysing Key Debates in Education and Sustainable Development in Relation to ESD Practice in Viet Nam

    ERIC Educational Resources Information Center

    Balls, Emily

    2016-01-01

    This article is based on qualitative field research carried out in Ha Noi, Viet Nam, in 2013 for an MA dissertation in Education and International Development at the UCL Institute of Education. It analyses interpretations of education for sustainable development (ESD) in Viet Nam, relating these to key debates around instrumental and democratic…

  13. Translations on North Korea No. 495

    DTIC Science & Technology

    1976-12-02

    Yun Ch’i-ho Hwang Ch’ol-san Kim Yong -yon comrade, KPA general, political committee member, and DPRK minister of peoples armed forces colonel...t’ae " So Kwan-hi functionary of the sector concerned Chong Song-nam Kim Sok-chin So Nam-sin Han Pyong- yong Wang Kyong-hak Ch’oe Sang-muk...Chin-t’ae Kim Sok-ki Yi Chong-mok Ch’oe Tu-kwang Han Su-kil Yi Yong -ch’ang [Pyongyang NODONG SINMUN in Korean 8 Oct 76 p 3] LOYALTY OATH

  14. Highly Soluble Benzo[ghi]perylenetriimide Derivatives: Stable and Air-Insensitive Electron Acceptors for Artificial Photosynthesis.

    PubMed

    Chen, Hung-Cheng; Hsu, Chao-Ping; Reek, Joost N H; Williams, René M; Brouwer, Albert M

    2015-11-01

    A series of new benzo[ghi]perylenetriimide (BPTI) derivatives has been synthesized and characterized. These remarkably soluble BPTI derivatives show strong optical absorption in the range of λ=300-500 nm and have a high triplet-state energy of 1.67 eV. A cyanophenyl substituent renders BPTI such a strong electron acceptor (Ered =-0.11 V vs. the normal hydrogen electrode) that electron-trapping reactions with O2 and H2 O do not occur. The BPTI radical anion on a fluorine-doped tin oxide|TiO2 electrode is persistent up to tens of seconds (t1/2 =39 s) in air-saturated buffer solution. As a result of favorable packing, theoretical electron mobilities (10(-2) ∼10(-1) cm(2) V(-1) s(-1)) are high and similar to the experimental values observed for perylene diimide and C60 derivatives. Our studies show the potential of the cyanophenyl-modified BPTI compounds as electron acceptors in devices for artificial photosynthesis in water splitting that are also very promising nonfullerene electron-transport materials for organic solar cells. © 2015 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  15. A situational review of infant and young child feeding practices and interventions in Viet Nam.

    PubMed

    Nguyen, Phuong Hong; Menon, Purnima; Ruel, Mariel; Hajeebhoy, Nemat

    2011-01-01

    Sub-optimal infant and young child feeding (IYCF) practices are likely a significant contributor to high undernutrition rates in Viet Nam. To date, however, there has been no comprehensive review of IYCF practices in Viet Nam. The objectives of this paper were to review: 1) patterns/trends in IYCF in Viet Nam; 2) the barriers and facilitators to IYCF practices; and 3) interventions and policies and their effectiveness. Methods used include reviewing and analyzing existing data, summarizing and organizing the evidence into broad themes based on a pre-defined conceptual framework. Findings show that the proportion of children ever breastfed is almost universal and the median duration of breastfeeding is 13-18 months. However, exclusive breastfeeding for the first six months is low (8-17%) and appears to be declining over time. Information on complementary feeding is limited, but two key challenges are: early introduction, and low nutrient quality of complementary foods. Facilitators of optimal IYCF were support from 1) government progressive policies, 2) non-profit organizations and 3) family members. Barriers to optimal IYCF included 1) the lack of enforcement of, and compliance with the code of marketing breast milk substitutes, 2) inadequate knowledge among health care providers; and 3) maternal poor knowledge. These findings indicate that the evidence base on complementary feeding is weak in Viet Nam and needs to be strengthened. The review also reinforces that program and policy actions to improve IYCF in Viet Nam must target multiple stakeholders at different levels: the family, the health system and the private sector.

  16. Pesticide regulations and farm worker safety: the need to improve pesticide regulations in Viet Nam

    PubMed Central

    Connell, Des; Miller, Greg; Rutherford, Shannon; Chu, Cordia

    2012-01-01

    Abstract Agricultural pesticide use in Viet Nam has more than tripled since 1990. However, pesticide legislation and regulations have not been developed in response to this large increase in usage, as a result of which pesticides pose a serious threat to human health and the environment. This paper identifies the need to improve pesticide regulations in Viet Nam through a comparative analysis of pesticide regulations in Viet Nam and the United States of America, where the rate of acute poisoning among agricultural workers is much lower than in Viet Nam and where information pertaining to pesticide regulations is made accessible to the public. The analysis identified several measures that would help to improve Viet Nam’s pesticide regulations. These include enhancing pesticide legislation, clarifying the specific roles and active involvement of both the environmental and health sectors; performing a comprehensive risk–benefit evaluation of pesticide registration and management practices; improving regulations on pesticide suspension and cancellation, transport, storage and disposal; developing import and export policies and enhancing pesticide-related occupational safety programmes. PMID:22690037

  17. Factors Associated With Adherence to Nasoalveolar Molding (NAM) by Caregivers of Infants Born With Cleft Lip and Palate.

    PubMed

    Esmonde, Nick O; Garfinkle, Judah S; Chen, Yiyi; Lambert, William E; Kuang, Anna A

    2018-02-01

    Identify factors associated with adherence to nasoalveolar molding (NAM) therapy. Retrospective case-control study. Tertiary referral center. Infants with cleft lip, with or without cleft palate, referred for NAM. One hundred thirty-five patients met criteria. Adherence to NAM therapy, defined as continuous use of the appliance and attendance of NAM adjustment visits. Female sex (OR = 2.85, 95% CI 1.21-6.74), bilateral cleft (OR = 2.88, 95% CI 1.29-6.46), and travel distance (OR = 1.01, 95% CI 1.00-1.01) were independent predictors of nonadherence. Bilateral clefts (OR = 8.35, 95% CI 2.72-25.64) and public-payer insurance (OR = 3.67, 95% CI 1.13-11.91) for male patients were significantly associated with nonadherence, in our sex-stratified multivariate model. The majority of the families (58%) had public health insurance. Males comprised 77.0% of the cohort. NAM treatment adherence is impaired by bilateral clefts, female sex, increased travel distance, and public insurance. Further studies are warranted to investigate how these factors affect adherence, and to develop interventions to improve adherence in families at risk due to economic or psychosocial barriers.

  18. Phenotypic assessments of peanut nested association mapping (NAM) populations

    USDA-ARS?s Scientific Manuscript database

    Nested association mapping (NAM) is a valuable innovation and multi-parental mapping population strategy in peanut genetics which increases the power to map quantitative trait loci and assists in extending the gene pool of elite peanut lines. In the peanut research community, two structured mapping ...

  19. Stimulating the development of national Streptococcus suis guidelines in Viet Nam through a strategic research partnership.

    PubMed

    Horby, Peter; Wertheim, Heiman; Ha, Nguyen Hong; Trung, Nguyen Vu; Trinh, Dao Tuyet; Taylor, Walter; Ha, Nguyen Minh; Lien, Trinh Thi Minh; Farrar, Jeremy; Van Kinh, Nguyen

    2010-06-01

    Streptococcus suis is a common cause of adult bacterial meningitis in Viet Nam, and possibly other parts of Asia, yet this disabling infection has been largely neglected. Prevention, diagnosis and treatment are relatively straightforward and affordable but, in early 2007, no national diagnostic, case management or prevention guidelines existed in Viet Nam. Enhanced detection of S. suis infections was established in 2007 as part of a collaborative research programme between the National Hospital for Tropical Diseases, a key national hospital with very close links to the Ministry of Health, and a research group affiliated with Oxford University based in Viet Nam. The results were reported directly to policy-makers at the Ministry of Health. Viet Nam is a low-income country with a health-care system that has seen considerable improvements and increased autonomy. However, parts of the system remain fairly centralized the Ministry of Health. Following the improved detection and reporting of S. suis cases, the Ministry of Health issued guidance to all hospitals in Viet Nam on the clinical and laboratory diagnosis, treatment and prevention of S. suis. A public health laboratory diagnostic service was established at the National Institute of Hygiene and Epidemiology and training courses were conducted for clinicians and microbiologists. Ministry of Health guidance on surveillance and control of communicable diseases was updated to include a section on S. suis. Research collaborations can efficiently inform and influence national responses if they are well positioned to reach policy-makers.

  20. Across the Board: Nam-Gyu Park.

    PubMed

    Park, Nam-Gyu

    2016-09-22

    In this series of articles, the board members of ChemSusChem discuss recent research articles that they consider of exceptional quality and importance for sustainability. This entry features Prof. Nam-Gyu Park, who highlights the recent work on mixed-cation mixed-anion perovskite materials toward high efficiency perovskite solar cells. He summarizes the work that has brought us to the current stage of research and suggests possible future paths for further advancement. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  1. Analysis of socio-political and health practices influencing sex ratio at birth in Viet Nam.

    PubMed

    Pham, Bang Nguyen; Hall, Wayne; Hill, Peter S; Rao, Chalapati

    2008-11-01

    Viet Nam has experienced rapid social change over the last decade, with a remarkable decline in fertility to just below replacement level. The combination of fertility decline, son preference, antenatal sex determination using ultrasound and sex selective abortion are key factors driving increased sex ratios at birth in favour of boys in some Asian countries. Whether or not this is taking place in Viet Nam as well is the subject of heightened debate. In this paper, we analyse the nature and determinants of sex ratio at birth in Viet Nam, including a small family size norm, recent reinforcement by the Government of the "one-to-two child" family policy, traditional son preference, easy access to antenatal ultrasound screening and legal abortion, and an increase in the proportion of one-child families. In order to prevent an increased sex ratio at birth in Viet Nam, we argue for the relaxation of the one-to-two child family policy and a return to the policy of "small family size" as determined by families, in tandem with a comprehensive approach to promoting the value of women and girls in society, countering traditional gender roles, and raising public awareness of the negative social consequences of a high sex ratio at birth.

  2. Globalization and the Governance of Education in Viet Nam

    ERIC Educational Resources Information Center

    London, Jonathan D.

    2010-01-01

    In a globalizing world, local and global governance arrangements are increasingly interdependent, which produces harmonization in some instances and new tensions and contradictions in others. Analysis shows that successive waves of globalization have affected the governance of education in Viet Nam differently. It shows that the globalization of…

  3. Delivery cost of human papillomavirus vaccination of young adolescent girls in Peru, Uganda and Viet Nam.

    PubMed

    Levin, Carol E; Van Minh, Hoang; Odaga, John; Rout, Swampa Sarit; Ngoc, Diep Nguyen Thi; Menezes, Lysander; Araujo, Maria Ana Mendoza; LaMontagne, D Scott

    2013-08-01

    To estimate the incremental delivery cost of human papillomavirus (HPV) vaccination of young adolescent girls in Peru, Uganda and Viet Nam. Data were collected from a sample of facilities that participated in five demonstration projects for hpv vaccine delivery: school-based delivery was used in Peru, Uganda and Viet Nam; health-centre-based delivery was also used in Viet Nam; and integrated delivery, which involved existing health services, was also used in Uganda. Microcosting methods were used to guide data collection on the use of resources (i.e. staff, supplies and equipment) and data were obtained from government, demonstration project and health centre administrative records. Delivery costs were expressed in 2009 United States dollars (US$). Exclusively project-related expenses and the cost of the vaccine were excluded. The economic delivery cost per vaccine dose ranged from US$ 1.44 for integrated outreach in Uganda to US$ 3.88 for school-based delivery in Peru. In Viet Nam, the lowest cost per dose was US$ 1.92 for health-centre-based delivery. Cost profiles revealed that, in general, the largest contributing factors were project start-up costs and recurrent personnel costs. The delivery cost of HPV vaccine was higher than published costs for traditional vaccines recommended by the Expanded Programme on Immunization (EPI). The cost of delivering HPV vaccine to young adolescent girls in Peru, Uganda and Viet Nam was higher than that for vaccines currently in the EPI schedule. The cost per vaccine dose was lower when delivery was integrated into existing health services.

  4. Circulation of influenza B lineages in northern Viet Nam, 2007-2014.

    PubMed

    Le, Thi Thanh; Pham, Thu Hang; Pham, Thi Hien; Nguyen, Le Khanh Hang; Nguyen, Co Thach; Hoang, Vu Mai Phuong; Tran, Thu Huong; Nguyen, Vu Son; Ngo, Huong Giang; Le, Quynh Mai

    2015-01-01

    Influenza B viruses circulate throughout Viet Nam, and their activities vary by region. There have been two antigenically distinct lineages of influenza B viruses co-circulating in the past 20 years; however, only one lineage is selected as a component of contemporary trivalent seasonal influenza vaccines. To improve the understanding of circulating influenza B lineages and influenza vaccine mismatches, we report the virus lineages circulating in northern Viet Nam over an eight-year period (2007-2014). Lineages of 331 influenza B viruses were characterized by haemagglutination inhibition assay against standard reference ferret (Yamagata) and sheep (Victoria) antisera. Sequence analysis of the haemagglutinin gene was performed in 64 selected influenza B isolates. The proportion of influenza B lineages changed by year. The Yamagata lineage predominated in 2007, 2008 and 2012; the Victoria lineage predominated in 2009-2014 except 2012. The two lineages showed continuous evolution over time. The Northern Hemisphere's influenza vaccine components were mismatched with the predominant circulating viruses in 2007, 2009 and 2014. The seasonality of influenza B activity is more variable in tropical and subtropical regions than in temperate zones. Our data showed a common co-circulation of both influenza B lineages in northern Viet Nam, and it was difficult to predict which one was the predominant lineage. Quadrivalent influenza vaccines containing both lineages may improve the effectiveness of influenza vaccine programmes in the future.

  5. The fourth national anti-tuberculosis drug resistance survey in Viet Nam.

    PubMed

    Nhung, N V; Hoa, N B; Sy, D N; Hennig, C M; Dean, A S

    2015-06-01

    Viet Nam's Fourth National Anti-Tuberculosis Drug Resistance Survey was conducted in 2011. To determine the prevalence of resistance to the four main first-line anti-tuberculosis drugs in Viet Nam. Eighty clusters were selected using a probability proportion to size approach. Drug susceptibility testing (DST) against the four main first-line anti-tuberculosis drugs was performed. A total of 1629 smear-positive tuberculosis (TB) patients were eligible for culture. Of these, DST results were available for 1312 patients, including 1105 new TB cases, 195 previously treated TB cases and 12 cases with an unknown treatment history. The proportion of cases with resistance to any drug was 32.7% (95%CI 29.1-36.5) among new cases and 54.2% (95%CI 44.3-63.7) among previously treated cases. The proportion of multidrug-resistant TB (MDR-TB) cases was 4.0% (95%CI 2.5-5.4) in new cases and 23.3 (95%CI 16.7-29.9) in previously treated cases. The fourth drug resistance survey in Viet Nam found that the proportion of MDR-TB among new and previously treated cases was not significantly different from that in the 2005 survey. The National TB Programme should prioritise the detection and treatment of MDR-TB to reduce transmission of MDR-TB in the community.

  6. News and Views: YAM@NAM 2007

    NASA Astrophysics Data System (ADS)

    2007-06-01

    The Young Astronomers' Meeting (YAM) sessions at NAM focused on extragalactic astrophysics and cosmology, with six invited up-and-coming speakers who showcased their work - and signed the YAM banner in true celebrity style! Organizers Mark Westmoquette, Anaïs Rassat and Joe Zuntz (pictured with the RAS President Michael Rowan-Robinson), believe that encouraging the nation's younger generation of astronomers is of primary importance for developing and sustaining the health of the UK astronomy community, and look forward to seeing YAM playing an increasingly central role in the future.

  7. Antibiotic use and resistance in emerging economies: a situation analysis for Viet Nam

    PubMed Central

    2013-01-01

    Background Antimicrobial resistance is a major contemporary public health threat. Strategies to contain antimicrobial resistance have been comprehensively set forth, however in developing countries where the need for effective antimicrobials is greatest implementation has proved problematic. A better understanding of patterns and determinants of antibiotic use and resistance in emerging economies may permit more appropriately targeted interventions. Viet Nam, with a large population, high burden of infectious disease and relatively unrestricted access to medication, is an excellent case study of the difficulties faced by emerging economies in controlling antimicrobial resistance. Methods Our working group conducted a situation analysis of the current patterns and determinants of antibiotic use and resistance in Viet Nam. International publications and local reports published between 1-1-1990 and 31-8-2012 were reviewed. All stakeholders analyzed the findings at a policy workshop and feasible recommendations were suggested to improve antibiotic use in Viet Nam. Here we report the results of our situation analysis focusing on: the healthcare system, drug regulation and supply; antibiotic resistance and infection control; and agricultural antibiotic use. Results Market reforms have improved healthcare access in Viet Nam and contributed to better health outcomes. However, increased accessibility has been accompanied by injudicious antibiotic use in hospitals and the community, with predictable escalation in bacterial resistance. Prescribing practices are poor and self-medication is common – often being the most affordable way to access healthcare. Many policies exist to regulate antibiotic use but enforcement is insufficient or lacking. Pneumococcal penicillin-resistance rates are the highest in Asia and carbapenem-resistant bacteria (notably NDM-1) have recently emerged. Hospital acquired infections, predominantly with multi-drug resistant Gram-negative organisms

  8. Antibiotic use and resistance in emerging economies: a situation analysis for Viet Nam.

    PubMed

    Nguyen, Kinh Van; Thi Do, Nga Thuy; Chandna, Arjun; Nguyen, Trung Vu; Pham, Ca Van; Doan, Phuong Mai; Nguyen, An Quoc; Thi Nguyen, Chuc Kim; Larsson, Mattias; Escalante, Socorro; Olowokure, Babatunde; Laxminarayan, Ramanan; Gelband, Hellen; Horby, Peter; Thi Ngo, Ha Bich; Hoang, Mai Thanh; Farrar, Jeremy; Hien, Tran Tinh; Wertheim, Heiman F L

    2013-12-10

    Antimicrobial resistance is a major contemporary public health threat. Strategies to contain antimicrobial resistance have been comprehensively set forth, however in developing countries where the need for effective antimicrobials is greatest implementation has proved problematic. A better understanding of patterns and determinants of antibiotic use and resistance in emerging economies may permit more appropriately targeted interventions.Viet Nam, with a large population, high burden of infectious disease and relatively unrestricted access to medication, is an excellent case study of the difficulties faced by emerging economies in controlling antimicrobial resistance. Our working group conducted a situation analysis of the current patterns and determinants of antibiotic use and resistance in Viet Nam. International publications and local reports published between 1-1-1990 and 31-8-2012 were reviewed. All stakeholders analyzed the findings at a policy workshop and feasible recommendations were suggested to improve antibiotic use in Viet Nam.Here we report the results of our situation analysis focusing on: the healthcare system, drug regulation and supply; antibiotic resistance and infection control; and agricultural antibiotic use. Market reforms have improved healthcare access in Viet Nam and contributed to better health outcomes. However, increased accessibility has been accompanied by injudicious antibiotic use in hospitals and the community, with predictable escalation in bacterial resistance. Prescribing practices are poor and self-medication is common - often being the most affordable way to access healthcare. Many policies exist to regulate antibiotic use but enforcement is insufficient or lacking.Pneumococcal penicillin-resistance rates are the highest in Asia and carbapenem-resistant bacteria (notably NDM-1) have recently emerged. Hospital acquired infections, predominantly with multi-drug resistant Gram-negative organisms, place additional strain on

  9. River Basin Water Assessment and Balance in fast developing areas in Viet Nam

    NASA Astrophysics Data System (ADS)

    Le, Van Chin; Ranzi, Roberto

    2010-05-01

    Uneven precipitation in space and time together with mismanagement and lack of knowledge about quantity and quality of water resources, have caused water shortages for water supply to large cities and irrigation areas in many regions of Viet Nam in the dry season. The rainy season (from June to October) counts for 80% of the total annual rainfall, while the water volume of dry season (from November to May of the following year) accounts for 20% only. Lack of sufficient water volumes occurs in some areas where the pressure of a fast increasing population (1.3% per year on average in the last decade in Viet Nam), intensive agricultural and industrial uses is one of the major problems facing sustainable development. For those areas an accurate water assessment and balance at the riverbasin scale is needed to manage the exploitation and appropriate use of water resources and plan future development. The paper describes the preliminary phase of the pilot development of the river basin water balance for the Day River Basin in the Red River delta in Viet Nam. The Day river basin includes a 7,897 km² area in the south-western part of the Red River in Viet Nam. The total population in the Day river basin exceeds 8 millions inhabitants, including the Hanoi capital, Nam Dinh and other large towns. Agricultural land covered 390,294 ha in 2000 and this area is going to be increased by 14,000 ha in 2010 due to land reclamation and expansion toward the sea. Agricultural uses exploit about 90% of surface water resources in the Day river basin but have to compete with industrial and civil needs in the recent years. At the background of the brief characterization of the Day River Basin, we concentrate on the application of a water balance model integrated by an assessment of water quality after consumptive uses for civil, agricultural and industrial needs to assist water management in the basin. In addition, future development scenarios are taken into account, considering less

  10. Delivery cost of human papillomavirus vaccination of young adolescent girls in Peru, Uganda and Viet Nam

    PubMed Central

    Van Minh, Hoang; Odaga, John; Rout, Swampa Sarit; Ngoc, Diep Nguyen Thi; Menezes, Lysander; Araujo, Maria Ana Mendoza; LaMontagne, D Scott

    2013-01-01

    Abstract Objective To estimate the incremental delivery cost of human papillomavirus (HPV) vaccination of young adolescent girls in Peru, Uganda and Viet Nam. Methods Data were collected from a sample of facilities that participated in five demonstration projects for HPV vaccine delivery: school-based delivery was used in Peru, Uganda and Viet Nam; health-centre-based delivery was also used in Viet Nam; and integrated delivery, which involved existing health services, was also used in Uganda. Microcosting methods were used to guide data collection on the use of resources (i.e. staff, supplies and equipment) and data were obtained from government, demonstration project and health centre administrative records. Delivery costs were expressed in 2009 United States dollars (US$). Exclusively project-related expenses and the cost of the vaccine were excluded. Findings The economic delivery cost per vaccine dose ranged from US$ 1.44 for integrated outreach in Uganda to US$ 3.88 for school-based delivery in Peru. In Viet Nam, the lowest cost per dose was US$ 1.92 for health-centre-based delivery. Cost profiles revealed that, in general, the largest contributing factors were project start-up costs and recurrent personnel costs. The delivery cost of HPV vaccine was higher than published costs for traditional vaccines recommended by the Expanded Programme on Immunization (EPI). Conclusion The cost of delivering HPV vaccine to young adolescent girls in Peru, Uganda and Viet Nam was higher than that for vaccines currently in the EPI schedule. The cost per vaccine dose was lower when delivery was integrated into existing health services. PMID:23940406

  11. Towards a lifelong learning society through reading promotion: Opportunities and challenges for libraries and community learning centres in Viet Nam

    NASA Astrophysics Data System (ADS)

    Hossain, Zakir

    2016-04-01

    The government of Viet Nam has made a commitment to build a Lifelong Learning Society by 2020. A range of related initiatives have been launched, including the Southeast Asian Ministers of Education Organization Centre for Lifelong Learning (SEAMEO CELLL) and "Book Day" - a day aimed at encouraging reading and raising awareness of its importance for the development of knowledge and skills. Viet Nam also aims to implement lifelong learning (LLL) activities in libraries, museums, cultural centres and clubs. The government of Viet Nam currently operates more than 11,900 Community Learning Centres (CLCs) and is in the process of both renovating and innovating public libraries and museums throughout the country. In addition to the work undertaken by the Viet Nam government, a number of enterprises have been initiated by non-governmental organisations and non-profit organisations to promote literacy and lifelong learning. This paper investigates some government initiatives focused on libraries and CLCs and their impact on reading promotion. Proposing a way forward, the paper confirms that Viet Nam's libraries and CLCs play an essential role in promoting reading and building a LLL Society.

  12. Innovative data tools: a suite for managing peer outreach to key affected populations in Viet Nam

    PubMed Central

    Jacka, David; Van Hai, Nguyen; Trinh, Nguyen Kieu; Boisen, Neil; Neukom, Josselyn

    2012-01-01

    Problem The paper tools used to monitor outreach work in all major cities in Viet Nam had substantial writing requirements for each contact with difficulty maintaining confidentiality. Action This paper describes the development of a Unique Identifier Code (UIC), a field data collection notebook (databook) and a computer data entry system in Viet Nam. The databook can document 40 individual clients and has space for commodity distribution, group contacts and needles/syringe collection for each month. Outcome Field implementation trials of the UIC and databook have been undertaken by more than 160 peer outreach workers to document their work with people who inject drugs (PWID) and sex workers (SW). Following an expanded trial in Hai Phong province, there have been requests for national circulation of the databook to be used by peer educators documenting outreach to PWID, SW and men who have sex with men. The standardized UIC and databook, in a variety of locally adapted formats, have now been introduced in more than 40 of the 63 provinces in Viet Nam. Discussion This development in Viet Nam is, to our knowledge, the first example of the combination of a confidential UIC and an innovative, simple pocket-sized paper instrument with associated customized data-entry software for documenting outreach. PMID:23908919

  13. Innovative data tools: a suite for managing peer outreach to key affected populations in Viet Nam.

    PubMed

    Nga, Nguyen Thien; Jacka, David; Van Hai, Nguyen; Trinh, Nguyen Kieu; Boisen, Neil; Neukom, Josselyn

    2012-07-01

    The paper tools used to monitor outreach work in all major cities in Viet Nam had substantial writing requirements for each contact with difficulty maintaining confidentiality. This paper describes the development of a Unique Identifier Code (UIC), a field data collection notebook (databook) and a computer data entry system in Viet Nam. The databook can document 40 individual clients and has space for commodity distribution, group contacts and needles/syringe collection for each month. Field implementation trials of the UIC and databook have been undertaken by more than 160 peer outreach workers to document their work with people who inject drugs (PWID) and sex workers (SW). Following an expanded trial in Hai Phong province, there have been requests for national circulation of the databook to be used by peer educators documenting outreach to PWID, SW and men who have sex with men. The standardized UIC and databook, in a variety of locally adapted formats, have now been introduced in more than 40 of the 63 provinces in Viet Nam. This development in Viet Nam is, to our knowledge, the first example of the combination of a confidential UIC and an innovative, simple pocket-sized paper instrument with associated customized data-entry software for documenting outreach.

  14. Completeness and consistency in recording information in the tuberculosis case register, Cambodia, China and Viet Nam.

    PubMed

    Hoa, N B; Wei, C; Sokun, C; Lauritsen, J M; Rieder, H L

    2010-10-01

    Tuberculosis (TB) case registers in Cambodia, two provinces in China and in Viet Nam. To determine completeness and consistency of information for quarterly reports on case finding and treatment outcome. A representative sample of TB case registers was selected in Cambodia, in two provinces in China and in Viet Nam. Quarterly reports were reproduced from double-entered, validated data to determine completeness and consistency. The dataset comprised 37,635 patient records in 2 calendar years. Only 0.2%, 3.6% and 1.1% of cases, respectively, in Cambodia, the two China provinces, and Viet Nam did not allow classification for the quarterly report on case finding. If the treatment outcome was reported as cured, it was correct in 99.9%, 85.7%, and 98.5% of the respective three jurisdictions: errors were mostly due to misclassification of completion as cure. Under-reporting of failures was more frequent than over-reporting in Cambodia and Viet Nam, while in the two provinces in China 84% of reported failures did not actually meet the bacteriological criterion. This evaluation demonstrates that recording essential information is exemplary in all three countries. It will be essential to carefully supervise the ability of staff to correctly define TB treatment outcome results in all three countries.

  15. The promises and perils of hospital autonomy: reform by decree in Viet Nam.

    PubMed

    London, Jonathan D

    2013-11-01

    This article investigates impacts of hospital autonomization in Viet Nam employing a "decision-space" framework that examines how hospitals have used their increased discretion and to what effect. Analysis suggests autonomization is associated with increased revenue, increasing staff pay, and greater investment in infrastructure and equipment. But autonomization is also associated with more costly and intensive treatment methods of uncertain contribution to the Vietnamese government's stated goal of quality healthcare for all. Impacts of autonomization in district hospitals are less striking. Despite certain limitations, the analysis generates key insights into early stages of hospital autonomization in Viet Nam. Copyright © 2013 The Author. Published by Elsevier Ltd.. All rights reserved.

  16. Evaporation variability of Nam Co Lake in the Tibetan Plateau and its role in recent rapid lake expansion

    NASA Astrophysics Data System (ADS)

    Ma, Ning; Szilagyi, Jozsef; Niu, Guo-Yue; Zhang, Yinsheng; Zhang, Teng; Wang, Binbin; Wu, Yanhong

    2016-06-01

    Previous studies have shown that the majority of the lakes in the Tibetan Plateau (TP) started to expand rapidly since the late 1990s. However, the causes are still not well known. For Nam Co, being a closed lake with no outflow, evaporation (EL) over the lake surface is the only way water may leave the lake. Therefore, quantifying EL is key for investigating the mechanism of lake expansion in the TP. EL can be quantified by Penman- and/or bulk-transfer-type models, requiring only net radiation, temperature, humidity and wind speed for inputs. However, interpolation of wind speed data may be laden with great uncertainty due to extremely sparse ground meteorological observations, the highly heterogeneous landscape and lake-land breeze effects. Here, evaporation of Nam Co Lake was investigated within the 1979-2012 period at a monthly time-scale using the complementary relationship lake evaporation (CRLE) model which does not require wind speed data. Validations by in-situ observations of E601B pan evaporation rates at the shore of Nam Co Lake as well as measured EL over an adjacent small lake using eddy covariance technique suggest that CRLE is capable of simulating EL well since it implicitly considers wind effects on evaporation via its vapor transfer coefficient. The multi-year average of annual evaporation of Nam Co Lake is 635 mm. From 1979 to 2012, annual evaporation of Nam Co Lake expressed a very slight decreasing trend. However, a more significant decrease in EL occurred during 1998-2008 at a rate of -12 mm yr-1. Based on water-level readings, this significant decrease in lake evaporation was found to be responsible for approximately 4% of the reported rapid water level increase and areal expansion of Nam Co Lake during the same period.

  17. OptoGluNAM4.1, a Photoswitchable Allosteric Antagonist for Real-Time Control of mGlu4 Receptor Activity.

    PubMed

    Rovira, Xavier; Trapero, Ana; Pittolo, Silvia; Zussy, Charleine; Faucherre, Adèle; Jopling, Chris; Giraldo, Jesús; Pin, Jean-Philippe; Gorostiza, Pau; Goudet, Cyril; Llebaria, Amadeu

    2016-08-18

    OptoGluNAM4.1, a negative allosteric modulator (NAM) of metabotropic glutamate receptor 4 (mGlu4) contains a reactive group that covalently binds to the receptor and a blue-light-activated, fast-relaxing azobenzene group that allows reversible receptor activity photocontrol in vitro and in vivo. OptoGluNAM4.1 induces light-dependent behavior in zebrafish and reverses the activity of the mGlu4 agonist LSP4-2022 in a mice model of chronic pain, defining a photopharmacological tool to better elucidate the physiological roles of the mGlu4 receptor in the nervous system. Copyright © 2016 Elsevier Ltd. All rights reserved.

  18. Maternal health care utilization in Viet Nam: increasing ethnic inequity.

    PubMed

    Målqvist, Mats; Lincetto, Ornella; Du, Nguyen Huy; Burgess, Craig; Hoa, Dinh Thi Phuong

    2013-04-01

    To investigate changes that took place between 2006 and 2010 in the inequity gap for antenatal care attendance and delivery at health facilities among women in Viet Nam. Demographic, socioeconomic and obstetric data for women aged 15-49 years were extracted from Viet Nam's Multiple Indicator Cluster Survey for 2006 (MICS3) and 2010-2011 (MICS4). Multivariate logistic regression was performed to determine if antenatal care attendance and place of delivery were significantly associated with maternal education, maternal ethnicity (Kinh/Hoa versus other), household wealth and place of residence (urban versus rural). These independent variables correspond to the analytical framework of the Commission on Social Determinants of Health. Large discrepancies between urban and rural populations were found in both MICS3 and MICS4. Although antenatal care attendance and health facility delivery rates improved substantially between surveys (from 86.3 to 92.1% and from 76.2 to 89.7%, respectively), inequities increased, especially along ethnic lines. The risk of not giving birth in a health facility increased significantly among ethnic minority women living in rural areas. In 2006 this risk was nearly five times higher than among women of Kinh/Hoa (majority) ethnicity (odds ratio, OR: 4.67; 95% confidence interval, CI: 2.94-7.43); in 2010-2011 it had become nearly 20 times higher (OR: 18.8; 95% CI: 8.96-39.2). Inequity in maternal health care utilization has increased progressively in Viet Nam, primarily along ethnic lines, and vulnerable groups in the country are at risk of being left behind. Health-care decision-makers should target these groups through affirmative action and culturally sensitive interventions.

  19. Criteria for prioritization of HIV programs in Viet Nam: a discrete choice experiment.

    PubMed

    Safarnejad, Ali; Pavlova, Milena; Son, Vo Hai; Phuong, Huynh Lan; Groot, Wim

    2017-11-13

    With the decline in funding for Viet Nam's response to the HIV epidemic, there is a need for evidence on the criteria to guide the prioritization of HIV programs. There is a gap in the research on the relative importance of multiple criteria for prioritizing a package of interventions. This study elicits preferences and the trade-offs made between different HIV programs by relevant stakeholders and decision-makers in Viet Nam. It also pays attention to how differences in social and professional characteristics of stakeholders and their agency affiliations shape preferences for HIV program criteria in Viet Nam. This study uses self-explicated ranking and discrete choice experiments to determine the relative importance of five criteria - effectiveness, feasibility, cost-effectiveness, rate of investment and prevention/treatment investment ratio - to stakeholders when they evaluate and select hypothetical HIV programs. The study includes 69 participants from government, civil society, and international development partners. Results of the discrete choice experiment show that overall the feasibility criterion is ranked highest in importance to the participants when choosing a hypothetical HIV program, followed by sustainability, treatment to prevention spending ratio, and effectiveness. The participant's work in management, programming, or decision-making has a significant effect on the importance of some criteria to the participant. In the self-explicated ranking effectiveness is the most important criterion and the cost-effectiveness criterion ranks low in importance across all groups. This study has shown that the preferred HIV program in Viet Nam is feasible, front-loaded for sustainability, has a higher proportion of investment on prevention, saves more lives and prevents more infections. Similarities in government and civil society rankings of criteria can create common grounds for future policy dialogues between stakeholders. Innovative models of planning should

  20. Some Aspects of the Teaching of English in Viet Nam.

    ERIC Educational Resources Information Center

    Le Van Diem

    In regard to the teaching of English, which is replacing French as a foreign language, Viet Nam presents some unique aspects and some individual problems. More secondary school students are selecting English as their foreign language choice; English departments in the universities are expanding rapidly; the teacher shortage is increasing. One…

  1. Evolutionary history of the NAM-B1 gene in wild and domesticated tetraploid wheat.

    PubMed

    Lundström, Maria; Leino, Matti W; Hagenblad, Jenny

    2017-12-20

    The NAM-B1 gene in wheat has for almost three decades been extensively studied and utilized in breeding programs because of its significant impact on grain protein and mineral content and pleiotropic effects on senescence rate and grain size. First detected in wild emmer wheat, the wild-type allele of the gene has been introgressed into durum and bread wheat. Later studies have, however, also found the presence of the wild-type allele in some domesticated subspecies. In this study we trace the evolutionary history of the NAM-B1 in tetraploid wheat species and evaluate it as a putative domestication gene. Genotyping of wild and landrace tetraploid accessions showed presence of only null alleles in durum. Domesticated emmer wheats contained both null alleles and the wild-type allele while wild emmers, with one exception, only carried the wild-type allele. One of the null alleles consists of a deletion that covers several 100 kb. The other null-allele, a one-basepair frame-shift insertion, likely arose among wild emmer. This allele was the target of a selective sweep, extending over several 100 kb. The NAM-B1 gene fulfils some criteria for being a domestication gene by encoding a trait of domestication relevance (seed size) and is here shown to have been under positive selection. The presence of both wild-type and null alleles in domesticated emmer does, however, suggest the gene to be a diversification gene in this species. Further studies of genotype-environment interactions are needed to find out under what conditions selection on different NAM-B1 alleles have been beneficial.

  2. Implementation of GINA guidelines in Ho Chi Minh City: a model for Viet Nam.

    PubMed

    Tho, N V; Loan, H T H; Thao, N T P; Dung, N T T; Lan, L T T

    2012-12-21

    The Global Initiative for Asthma (GINA) guidelines have not been implemented effectively in primary care settings in Viet Nam. To estimate the proportion of patients with controlled asthma and the direct health care costs of managing asthma according to GINA guidelines at four out-patient clinics in Ho Chi Minh City (HCMC), Viet Nam. One hundred and six patients with asthma were treated and followed up according to GINA guidelines for 12 months. Clinical and pulmonary function responses and direct health care costs were evaluated every 3 months during the study. The proportion of patients with controlled asthma rose from 1.0% at the start of the study to 36.8% by the end of the study (P < 0.0001). The proportion of patients who had at least one hospitalisation per year decreased significantly, from 32.1% to 5.7% (P < 0.0001). The annual per patient median direct health care cost was US$169. Using asthma controllers continuously gave better asthma control than using them intermittently (OR 12.9, 95%CI 4.7-35.7). The implementation of GINA guidelines at out-patient clinics in HCMC, Viet Nam, improved asthma control with modest direct health care costs.

  3. The Scientific and Technical Revolution in the Socialist Republic of Viet Nam.

    ERIC Educational Resources Information Center

    Vien, Nguyen Khac

    1979-01-01

    Discussed are the reasons for the Socialist Republic of Viet Nam's scientific backwardness. A development project which will enable this country to become a modern, economically self-sufficient country by the year 2000 is outlined. (BT)

  4. The formulation and implementation of a national helmet law: a case study from Viet Nam.

    PubMed

    Passmore, Jonathon W; Nguyen, Lan Huong; Nguyen, Nam Phuong; Olivé, Jean-Marc

    2010-10-01

    Road traffic injuries are a leading cause of death and disability in Viet Nam. In 2008, official data reported 11 243 deaths and 7771 serious injuries on the roads, of which an estimated 60% of fatalities occur in motorcycle riders and passengers. In recognition of this problem, Viet Nam has had partial motorcycle helmet legislation since 1995. However, for a variety of reasons, implementation and enforcement have been limited. On 15 December 2007, Viet Nam's first comprehensive mandatory helmet law came into effect, covering all riders and passengers on all roads nationwide. Penalties increased ten-fold and cohorts of police were mobilized for enforcement. The Viet Nam national helmet legislation was developed and implemented by the National Traffic Safety Committee. Despite past barriers to enforcement, increased policing in 2008 led to 680 000 infringements being issued for non-helmet wearing. While changes in helmet wearing were not nationally observed, significant increases were documented in selected provinces in the first six months of the law's introduction. In Da Nang, helmet wearing increased from 27 to 99%. In the first three months after the law took effect, surveillance data from 20 urban and rural hospitals, found the risk of road traffic head injuries and deaths decreased by 16% and 18% respectively. Political leadership, intensive advanced public education and stringent enforcement have contributed to the successful implementation of the new law. Through continual monitoring of the legislation, loopholes detrimental to the effectiveness of the law have been identified and addressed.

  5. The formulation and implementation of a national helmet law: a case study from Viet Nam

    PubMed Central

    Nguyen, Lan Huong; Nguyen, Nam Phuong; Olivé, Jean-Marc

    2010-01-01

    Abstract Problem Road traffic injuries are a leading cause of death and disability in Viet Nam. In 2008, official data reported 11 243 deaths and 7771 serious injuries on the roads, of which an estimated 60% of fatalities occur in motorcycle riders and passengers. In recognition of this problem, Viet Nam has had partial motorcycle helmet legislation since 1995. However, for a variety of reasons, implementation and enforcement have been limited. Approach On 15 December 2007, Viet Nam's first comprehensive mandatory helmet law came into effect, covering all riders and passengers on all roads nationwide. Penalties increased ten-fold and cohorts of police were mobilized for enforcement. Local setting The Viet Nam national helmet legislation was developed and implemented by the National Traffic Safety Committee. Relevant changes Despite past barriers to enforcement, increased policing in 2008 led to 680 000 infringements being issued for non-helmet wearing. While changes in helmet wearing were not nationally observed, significant increases were documented in selected provinces in the first six months of the law’s introduction. In Da Nang, helmet wearing increased from 27 to 99%. In the first three months after the law took effect, surveillance data from 20 urban and rural hospitals, found the risk of road traffic head injuries and deaths decreased by 16% and 18% respectively. Lessons learnt Political leadership, intensive advanced public education and stringent enforcement have contributed to the successful implementation of the new law. Through continual monitoring of the legislation, loopholes detrimental to the effectiveness of the law have been identified and addressed. PMID:20931064

  6. Inclusion in Viet Nam: More than a Decade of Implementation.

    ERIC Educational Resources Information Center

    Villa, Richard A.; Tac, Le Van; Muc, Pham Minh; Ryan, Susan; Thuy, Nguyen Thi Minh; Weill, Cindy; Thousand, Jacqueline S.

    2003-01-01

    This article traces the evolution of special education policies and services and the introduction of inclusive education as a service delivery model in Viet Nam. The impact of a series of inclusion projects and resultant goals of the Ministry of Education and Training to expand inclusive education are described. (Contains 8 references.) (Author/CR)

  7. Financial burden of household out-of pocket health expenditure in Viet Nam: findings from the National Living Standard Survey 2002-2010.

    PubMed

    Van Minh, Hoang; Kim Phuong, Nguyen Thi; Saksena, Priyanka; James, Chris D; Xu, Ke

    2013-11-01

    In Viet Nam, household direct out-of-pocket (OOP) health expenditure as a share of the total health expenditure has been always high, ranging from 50% to 70%. The high share of OOP expenditure has been linked to different inequity problems such as catastrophic health expenditure (households must reduce their expenditure on other necessities) and impoverishment. This paper aims to examine catastrophic and poverty impacts of household out-of-pocket health expenditure in Viet Nam over time and identify socio-economic indicators associated with them. Data used in this research were obtained from a nationally representative household survey, Viet Nam Living Standard Survey 2002, 2004, 2006, 2008 and 2010. The findings revealed that there were problems in health care financing in Viet Nam - many households encountered catastrophic health expenditure and/or were pushed into poverty due to health care payments. The issues were pervasive over time. Catastrophic expenditure and impoverishment problems were more common among the households who had more elderly people and those located in rural areas. Importantly, the financial protection aspect of the national health insurance schemes was still modest. Given these findings, more attention is needed on developing methods of financial protection in Viet Nam. Copyright © 2012 Elsevier Ltd. All rights reserved.

  8. Circulation of influenza B lineages in northern Viet Nam, 2007–2014

    PubMed Central

    Le, Thi Thanh; Pham, Thu Hang; Pham, Thi Hien; Nguyen, Le Khanh Hang; Hoang, Vu Mai Phuong; Tran, Thu Huong; Nguyen, Vu Son; Ngo, Huong Giang

    2015-01-01

    Introduction Influenza B viruses circulate throughout Viet Nam, and their activities vary by region. There have been two antigenically distinct lineages of influenza B viruses co-circulating in the past 20 years; however, only one lineage is selected as a component of contemporary trivalent seasonal influenza vaccines. To improve the understanding of circulating influenza B lineages and influenza vaccine mismatches, we report the virus lineages circulating in northern Viet Nam over an eight-year period (2007–2014). Methods Lineages of 331 influenza B viruses were characterized by haemagglutination inhibition assay against standard reference ferret (Yamagata) and sheep (Victoria) antisera. Sequence analysis of the haemagglutinin gene was performed in 64 selected influenza B isolates. Results The proportion of influenza B lineages changed by year. The Yamagata lineage predominated in 2007, 2008 and 2012; the Victoria lineage predominated in 2009–2014 except 2012. The two lineages showed continuous evolution over time. The Northern Hemisphere’s influenza vaccine components were mismatched with the predominant circulating viruses in 2007, 2009 and 2014. Discussion The seasonality of influenza B activity is more variable in tropical and subtropical regions than in temperate zones. Our data showed a common co-circulation of both influenza B lineages in northern Viet Nam, and it was difficult to predict which one was the predominant lineage. Quadrivalent influenza vaccines containing both lineages may improve the effectiveness of influenza vaccine programmes in the future. PMID:26798557

  9. Surface ozone at Nam Co in the inland Tibetan Plateau: variation, synthesis comparison and regional representativeness

    NASA Astrophysics Data System (ADS)

    Yin, Xiufeng; Kang, Shichang; de Foy, Benjamin; Cong, Zhiyuan; Luo, Jiali; Zhang, Lang; Ma, Yaoming; Zhang, Guoshuai; Rupakheti, Dipesh; Zhang, Qianggong

    2017-09-01

    Ozone is an important pollutant and greenhouse gas, and tropospheric ozone variations are generally associated with both natural and anthropogenic processes. As one of the most pristine and inaccessible regions in the world, the Tibetan Plateau has been considered as an ideal region for studying processes of the background atmosphere. Due to the vast area of the Tibetan Plateau, sites in the southern, northern and central regions exhibit different patterns of variation in surface ozone. Here, we present continuous measurements of surface ozone mixing ratios at Nam Co Station over a period of ˜ 5 years (January 2011 to October 2015), which is a background site in the inland Tibetan Plateau. An average surface ozone mixing ratio of 47.6 ± 11.6 ppb (mean ± standard deviation) was recorded, and a large annual cycle was observed with maximum ozone mixing ratios in the spring and minimum ratios during the winter. The diurnal cycle is characterized by a minimum in the early morning and a maximum in the late afternoon. Nam Co Station represents a background region where surface ozone receives negligible local anthropogenic emissions inputs, and the anthropogenic contribution from South Asia in spring and China in summer may affect Nam Co Station occasionally. Surface ozone at Nam Co Station is mainly dominated by natural processes involving photochemical reactions, vertical mixing and downward transport of stratospheric air mass. Model results indicate that the study site is affected differently by the surrounding areas in different seasons: air masses from the southern Tibetan Plateau contribute to the high ozone levels in the spring, and enhanced ozone levels in the summer are associated with air masses from the northern Tibetan Plateau. By comparing measurements at Nam Co Station with those from other sites on the Tibetan Plateau, we aim to expand the understanding of ozone cycles and transport processes over the Tibetan

  10. Childhood Tuberculosis in Northern Viet Nam: A Review of 103 Cases

    PubMed Central

    Blount, Robert J.; Tran, Bao; Jarlsberg, Leah G.; Phan, Ha; Thanh Hoang, Van; Nguyen, Nhung Viet; Lewinsohn, Deborah A.; Nahid, Payam

    2014-01-01

    Background Childhood tuberculosis causes significant morbidity and mortality in Southeast Asia, yet little is known about the epidemiology and clinical characteristics of this disease in Viet Nam. Objectives To determine the demographics, clinical presentations, radiographic and microbiologic findings, treatment regimens, and outcomes of children admitted with tuberculosis (TB) to a national referral hospital in Viet Nam. Methods We conducted a retrospective case series study of children ≤ 15 years old with bacteriologically confirmed or clinically diagnosed TB admitted to a national referral hospital in Ha Noi, Viet Nam from January through December 2007. Results One hundred three children were identified: median age 5 years (IQR 2-10), 44% female, 99% Kinh ethnicity, 27% residing in Ha Noi, 88% with BCG vaccination, 27% with known TB contact, and 38% malnourished. Intrathoracic TB was present in 62%, extrathoracic in 52%, both intra and extrathoracic in 19%, and undetermined site in 5%. The most common extrathoracic manifestation was peripheral lymphadenitis, and children under 5 were more likely to have miliary TB or both intra and extrathoracic TB. Fever and failure to thrive were common presenting symptoms among all participants (65% and 56%, respectively), 66% of those with intrathoracic TB presented with cough, and 92% of those with TB meningitis presented with severe neurologic impairment. Acid-fast bacilli smears and mycobacterial cultures were positive in 18% and 21% of children tested, and histopathology was positive in 88% of those biopsied. There were no adverse drug reactions necessitating change in therapy, and no inpatient mortality. Conclusions Extrathoracic TB was common, treatment well tolerated and clinical outcomes excellent. Culture confirmation rates were low and emphasize the need for improved diagnostics. PMID:24818967

  11. Childhood tuberculosis in northern Viet Nam: a review of 103 cases.

    PubMed

    Blount, Robert J; Tran, Bao; Jarlsberg, Leah G; Phan, Ha; Thanh Hoang, Van; Nguyen, Nhung Viet; Lewinsohn, Deborah A; Nahid, Payam

    2014-01-01

    Childhood tuberculosis causes significant morbidity and mortality in Southeast Asia, yet little is known about the epidemiology and clinical characteristics of this disease in Viet Nam. To determine the demographics, clinical presentations, radiographic and microbiologic findings, treatment regimens, and outcomes of children admitted with tuberculosis (TB) to a national referral hospital in Viet Nam. We conducted a retrospective case series study of children ≤ 15 years old with bacteriologically confirmed or clinically diagnosed TB admitted to a national referral hospital in Ha Noi, Viet Nam from January through December 2007. One hundred three children were identified: median age 5 years (IQR 2-10), 44% female, 99% Kinh ethnicity, 27% residing in Ha Noi, 88% with BCG vaccination, 27% with known TB contact, and 38% malnourished. Intrathoracic TB was present in 62%, extrathoracic in 52%, both intra and extrathoracic in 19%, and undetermined site in 5%. The most common extrathoracic manifestation was peripheral lymphadenitis, and children under 5 were more likely to have miliary TB or both intra and extrathoracic TB. Fever and failure to thrive were common presenting symptoms among all participants (65% and 56%, respectively), 66% of those with intrathoracic TB presented with cough, and 92% of those with TB meningitis presented with severe neurologic impairment. Acid-fast bacilli smears and mycobacterial cultures were positive in 18% and 21% of children tested, and histopathology was positive in 88% of those biopsied. There were no adverse drug reactions necessitating change in therapy, and no inpatient mortality. Extrathoracic TB was common, treatment well tolerated and clinical outcomes excellent. Culture confirmation rates were low and emphasize the need for improved diagnostics.

  12. News and Views: Bottom-up boost at NAM; Spreading the word from the NAM; S3 gets together at the NAM; YAM@NAM 2007

    NASA Astrophysics Data System (ADS)

    2007-06-01

    Delegates at the simultaneous National Astronomy Meeting, UK Solar Physics meeting and Spring MIST meeting were impressed by the warm welcome and efficient organization from the hosts, the University of Central Lancaster in Preston. The meetings were successful in terms of the number of participants and the breadth and depth of science discussed, but also in terms of the spread of that science across the media. The newly formed Solar System Science (S3) group (see A&G 47 4.39) met at the National Astronomy Meeting hosted by the University of Central Lancaster at Preston in April. The meeting was well attended and many pressing issues were discussed, reflecting a productive first year. The Young Astronomers' Meeting (YAM) sessions at NAM focused on extragalactic astrophysics and cosmology, with six invited up-and-coming speakers who showcased their work - and signed the YAM banner in true celebrity style! Organizers Mark Westmoquette, Anaïs Rassat and Joe Zuntz (pictured with the RAS President Michael Rowan-Robinson), believe that encouraging the nation's younger generation of astronomers is of primary importance for developing and sustaining the health of the UK astronomy community, and look forward to seeing YAM playing an increasingly central role in the future.

  13. Phylodynamics of Enterovirus A71-Associated Hand, Foot, and Mouth Disease in Viet Nam.

    PubMed

    Geoghegan, Jemma L; Tan, Le Van; Kühnert, Denise; Halpin, Rebecca A; Lin, Xudong; Simenauer, Ari; Akopov, Asmik; Das, Suman R; Stockwell, Timothy B; Shrivastava, Susmita; Ngoc, Nghiem My; Uyen, Le Thi Tam; Tuyen, Nguyen Thi Kim; Thanh, Tran Tan; Hang, Vu Thi Ty; Qui, Phan Tu; Hung, Nguyen Thanh; Khanh, Truong Huu; Thinh, Le Quoc; Nhan, Le Nguyen Thanh; Van, Hoang Minh Tu; Viet, Do Chau; Tuan, Ha Manh; Viet, Ho Lu; Hien, Tran Tinh; Chau, Nguyen Van Vinh; Thwaites, Guy; Grenfell, Bryan T; Stadler, Tanja; Wentworth, David E; Holmes, Edward C; Van Doorn, H Rogier

    2015-09-01

    Enterovirus A71 (EV-A71) is a major cause of hand, foot, and mouth disease (HFMD) and is particularly prevalent in parts of Southeast Asia, affecting thousands of children and infants each year. Revealing the evolutionary and epidemiological dynamics of EV-A71 through time and space is central to understanding its outbreak potential. We generated the full genome sequences of 200 EV-A71 strains sampled from various locations in Viet Nam between 2011 and 2013 and used these sequence data to determine the evolutionary history and phylodynamics of EV-A71 in Viet Nam, providing estimates of the effective reproduction number (Re) of the infection through time. In addition, we described the phylogeography of EV-A71 throughout Southeast Asia, documenting patterns of viral gene flow. Accordingly, our analysis reveals that a rapid genogroup switch from C4 to B5 likely took place during 2012 in Viet Nam. We show that the Re of subgenogroup C4 decreased during the time frame of sampling, whereas that of B5 increased and remained >1 at the end of 2013, corresponding to a rise in B5 prevalence. Our study reveals that the subgenogroup B5 virus that emerged into Viet Nam is closely related to variants that were responsible for large epidemics in Malaysia and Taiwan and therefore extends our knowledge regarding its associated area of endemicity. Subgenogroup B5 evidently has the potential to cause more widespread outbreaks across Southeast Asia. EV-A71 is one of many viruses that cause HFMD, a common syndrome that largely affects infants and children. HFMD usually causes only mild illness with no long-term consequences. Occasionally, however, severe infection may arise, especially in very young children, causing neurological complications and even death. EV-A71 is highly contagious and is associated with the most severe HFMD cases, with large and frequent epidemics of the virus recorded worldwide. Although major advances have been made in the development of a potential EV-A71

  14. Phylodynamics of Enterovirus A71-Associated Hand, Foot, and Mouth Disease in Viet Nam

    PubMed Central

    Kühnert, Denise; Halpin, Rebecca A.; Lin, Xudong; Simenauer, Ari; Akopov, Asmik; Das, Suman R.; Stockwell, Timothy B.; Shrivastava, Susmita; Ngoc, Nghiem My; Uyen, Le Thi Tam; Tuyen, Nguyen Thi Kim; Thanh, Tran Tan; Hang, Vu Thi Ty; Qui, Phan Tu; Hung, Nguyen Thanh; Khanh, Truong Huu; Thinh, Le Quoc; Nhan, Le Nguyen Thanh; Van, Hoang Minh Tu; Viet, Do Chau; Tuan, Ha Manh; Viet, Ho Lu; Hien, Tran Tinh; Chau, Nguyen Van Vinh; Thwaites, Guy; Grenfell, Bryan T.; Stadler, Tanja; Wentworth, David E.; Holmes, Edward C.; Van Doorn, H. Rogier

    2015-01-01

    ABSTRACT Enterovirus A71 (EV-A71) is a major cause of hand, foot, and mouth disease (HFMD) and is particularly prevalent in parts of Southeast Asia, affecting thousands of children and infants each year. Revealing the evolutionary and epidemiological dynamics of EV-A71 through time and space is central to understanding its outbreak potential. We generated the full genome sequences of 200 EV-A71 strains sampled from various locations in Viet Nam between 2011 and 2013 and used these sequence data to determine the evolutionary history and phylodynamics of EV-A71 in Viet Nam, providing estimates of the effective reproduction number (Re) of the infection through time. In addition, we described the phylogeography of EV-A71 throughout Southeast Asia, documenting patterns of viral gene flow. Accordingly, our analysis reveals that a rapid genogroup switch from C4 to B5 likely took place during 2012 in Viet Nam. We show that the Re of subgenogroup C4 decreased during the time frame of sampling, whereas that of B5 increased and remained >1 at the end of 2013, corresponding to a rise in B5 prevalence. Our study reveals that the subgenogroup B5 virus that emerged into Viet Nam is closely related to variants that were responsible for large epidemics in Malaysia and Taiwan and therefore extends our knowledge regarding its associated area of endemicity. Subgenogroup B5 evidently has the potential to cause more widespread outbreaks across Southeast Asia. IMPORTANCE EV-A71 is one of many viruses that cause HFMD, a common syndrome that largely affects infants and children. HFMD usually causes only mild illness with no long-term consequences. Occasionally, however, severe infection may arise, especially in very young children, causing neurological complications and even death. EV-A71 is highly contagious and is associated with the most severe HFMD cases, with large and frequent epidemics of the virus recorded worldwide. Although major advances have been made in the development of a

  15. The effects of placing an operational research fellow within the Viet Nam National Tuberculosis Programme.

    PubMed

    Hoa, N B; Nhung, N V; Kumar, A M V; Harries, A D

    2016-12-21

    In April 2009, an operational research fellow was placed within the Viet Nam National Tuberculosis Control Programme (NTP). Over the 6 years from 2010 to 2015, the OR fellow co-authored 21 tuberculosis research papers (as principal author in 15 [71%]). This constituted 23% of the 91 tuberculosis papers published in Viet Nam during this period. Of the 21 published papers, 16 (76%) contributed to changes in policy ( n = 8) and practice ( n = 8), and these in turn improved programme performance. Many papers also contributed important evidence for better programme planning. Highly motivated OR fellows embedded within NTPs can facilitate high-quality research and research uptake.

  16. Disease spectrum and management of children admitted with acute respiratory infection in Viet Nam.

    PubMed

    Nguyen, T K P; Nguyen, D V; Truong, T N H; Tran, M D; Graham, S M; Marais, B J

    2017-06-01

    To assess the acute respiratory infection (ARI) disease spectrum, duration of hospitalisation and outcome in children hospitalised with an ARI in Viet Nam. We conducted a retrospective descriptive study of ARI admissions to primary (Hoa Vang District Hospital), secondary (Da Nang Hospital for Women and Children) and tertiary (National Hospital of Paediatrics in Ha Noi) level hospitals in Viet Nam over 12 months (01/09/2015 to 31/08/2016). Acute respiratory infections accounted for 27.9% (37 436/134 061) of all paediatric admissions; nearly half (47.6%) of all children admitted to Hoa Vang District Hospital. Most (64.6%) of children hospitalised with an ARI were <2 years of age. Influenza/pneumonia accounted for 69.4% of admissions; tuberculosis for only 0.3%. Overall 284 (0.8%) children died; most deaths (269/284; 94.7%) occurred at the tertiary referral hospital. The average duration of hospitalisation was 7.6 days (median 7 days). The average direct hospitalisation cost per ARI admission was 157.5 USD in Da Nang Provincial Hospital. In total, 62.6% of admissions were covered by health insurance. Acute respiratory infection is a major cause of paediatric hospitalisation in Viet Nam, characterised by prolonged hospitalisation for relatively mild disease. There is huge potential to reduce unnecessary hospital admission and cost. © 2017 John Wiley & Sons Ltd.

  17. Clinical and Molecular Epidemiology of Human Parainfluenza Viruses 1-4 in Children from Viet Nam.

    PubMed

    Linster, Martin; Do, Lien Anh Ha; Minh, Ngo Ngoc Quang; Chen, Yihui; Zhe, Zhu; Tuan, Tran Anh; Tuan, Ha Manh; Su, Yvonne C F; van Doorn, H Rogier; Moorthy, Mahesh; Smith, Gavin J D

    2018-05-01

    HPIVs are serologically and genetically grouped into four species that account for up to 10% of all hospitalizations due to acute respiratory infection in children under the age of five. Genetic and epidemiological data for the four HPIVs derived from two pediatric cohorts in Viet Nam are presented. Respiratory samples were screened for HPIV1-4 by real-time PCR. Demographic and clinical data of patients infected with different HPIV were compared. We used a hemi-nested PCR approach to generate viral genome sequences from HPIV-positive samples and conducted a comprehensive phylogenetic analysis. In total, 170 samples tested positive for HPIV. HPIV3 was most commonly detected in our cohort and 80 co-detections of HPIV with other respiratory viruses were found. Phylogenetic analyses suggest local endemic circulation as well as punctuated introductions of new HPIV lineages. Viral gene flow analysis revealed that Viet Nam is a net importer of viral genetic diversity. Epidemiological analyses imply similar disease severity for all HPIV species. HPIV sequences from Viet Nam formed local clusters and were interspersed with sequences from diverse geographic regions. Combined, this new knowledge will help to investigate global HPIV circulation patterns in more detail and ultimately define more suitable vaccine strains.

  18. Participatory support to farmers in improving safety and health at work: building WIND farmer volunteer networks in Viet Nam.

    PubMed

    Kawakami, Tsuyoshi; Van, Vhu Nhu; Theu, Nguyen Van; Khai, Ton That; Kogi, Kazutaka

    2008-10-01

    The government of Viet Nam places a high priority on upgrading the quality of farmers' lives. Providing adequate occupational safety and health (OSH) protection for all farmers is an important challenge. The Ministry of Labour, Invalids and Social Affairs (MOLISA) of Viet Nam trained WIND (Work Improvement in Neighbourhood Development) farmer volunteers. From 2004-2007, MOLISA in cooperation with ministries of health and agriculture trained 480 WIND farmer volunteers in selected 14 provinces. Trained farmer volunteers trained their neighbouring farmers and expanded their networks. The WIND training programme produced in Cantho, Viet Nam in 1996, was used as the core training methodology. The WIND action-checklist, good example photo-sheets, and other participatory training materials were designed for WIND farmer volunteers as practical training tools. The volunteers trained 7,922 farmers. The trained farmers implemented 28,508 improvements in materials handling, work posture, machine and electrical safety, working environments and control of hazardous chemicals, and welfare facilities. The provincial support committees organized follow-up workshops and strengthen the WIND farmer volunteer networks. The system of WIND farmer volunteers proved effective in extending practical OSH protection measures to farmers at grassroots level. The system of WIND farmer volunteers was adopted in the First National Programme on Labour Protection and OSH of Viet Nam as a practical means in OSH and is now further expanding within the framework of the National Programme.

  19. Distance Education Policy and Public Awareness in Cambodia, Laos, and Viet Nam

    ERIC Educational Resources Information Center

    Vuth, Doung; Than, Chhuon Chan; Phanousith, Somphone; Phissamay, Phonpasit; Tai, Tran Thi

    2007-01-01

    The current project brings together academic and governmental specialists from Cambodia, Laos, and Viet Nam (CLV), in a collaborative study of the prospects for distance education (DE) in those countries. The study's overall objectives are to: (1) survey and take stock of existing educational scenarios and problems in CLV; (2) document the…

  20. Player or referee? Aid effectiveness and the governance of health policy development: Lessons from Viet Nam.

    PubMed

    Dodd, Rebecca; Olivé, Jean-Marc

    2011-01-01

    Viet Nam is one of the brightest stars in the constellation of developing countries. Its remarkable achievements in reducing poverty and improving health and education outcomes are well known, and as a result it has enjoyed generous aid programmes. Viet Nam also has a reputation for taking a strong lead in disciplining its donors and pushing for more efficient and effective forms of aid delivery, both at home and internationally. This article discusses how efforts to improve the effectiveness of aid intersect with policy-making processes in the health sector. It presents a quantitative review of health aid flows in Viet Nam and a qualitative analysis of the aid environment using event analysis, participant observation and key informant interviews. The analysis reveals a complex and dynamic web of incentives influencing the implementation of the aid effectiveness agenda in the health sector. There are contradictory forces within the Ministry of Health, within government as a whole, within the donor community and between donors and government. Analytical frameworks drawn from the study of policy networks and governance can help explain these tensions. They suggest that governance of health aid in Viet Nam is characterised by multiple, overlapping 'policy networks' which cut across the traditional donor-government divide. The principles of aid effectiveness make sense for some of these communities, but for others they are irrational and may lead to a loss of influence and resources. However, sustained engagement combined with the building of strategic coalitions can overcome individual and institutional incentives. This article suggests that aid reform efforts should be understood not as a technocratic agenda but as a political process with all the associated tensions, perverse incentives and challenges. Partners thus need to recognise - and find new ways of making sense of - the complexity of forces affecting aid delivery.

  1. Dengue Virus in Sub-tropical Northern and Central Viet Nam: Population Immunity and Climate Shape Patterns of Viral Invasion and Maintenance

    DTIC Science & Technology

    2013-12-05

    or the U.S. Government. * E-mail: j.aaskov@qut.edu.au Introduction Dengue viruses (DENV) are single-stranded, positive-sense, mosquito -borne RNA...transmission intensities, as cool winter temperatures in northern Viet Nam may reduce mosquito breeding and survival and increase extrinsic incubation times...Nam may reduce mosquito populations and virus replica- tion to levels that are not conducive to year-round DENV transmission. Finally, we found that

  2. Co-existence of Paragonimus harinasutai and Paragonimus bangkokensis metacercariae in fresh water crab hosts in central Viet Nam with special emphasis on their close phylogenetic relationship.

    PubMed

    Doanh, Pham Ngoc; Hien, Hoang Van; Nonaka, Nariaki; Horii, Yoichiro; Nawa, Yukifumi

    2012-09-01

    During our epidemiological surveys for Paragonimus species in central Viet Nam, we found four morphologically different Paragonimus metacercariae in mountainous crabs. They were identified as metacercariae of Paragonimus westermani, P. bangkokensis, P. proliferus, and P. harinasutai in the order of their prevalence in crab hosts. This is the first discovery of P. harinasutai in Viet Nam, co-inhabiting with P. bangkokensis and other species. Metacercariae of P. harinasutai were given orally to a cat to obtain adult worms. Then, ITS2 and CO1 sequences of metacercariae and adults of P. harinasutai, and metacercariae of P. bangkokensis collected from the same place were determined for analyses of phylogenetic relationships to other P. harinasutai and P. bangkokensis populations as well as related species. The results of molecular analyses showed that P. harinasutai from Quang Binh province of central Viet Nam was almost completely identical with those from Vientiane, Lao PDR; P. bangkokensis from Quang Binh, Viet Nam was also almost completely identical with those from Lao PDR and from Quang Ninh province, Viet Nam. Except for one P. harinasutai isolate from China, all populations of P. harinasutai and P. bangkokensis from Thailand, Lao and Viet Nam make a single clade in both ITS2 and CO1 trees. In ITS2 sequences, AT deletion and ATC insertion were observed in some isolates of both species, indicating recent gene flow between P. harinasutai and P. bangkokensis. Moreover, because of their extremely high genetic similarities and their co-inhabitation in the same crab hosts found in Thailand, Lao PDR and Viet Nam, they should be considered as the sister species at the early stage of divergence. In addition, P. microrchis previously described from Yunnan, China should be placed as the synonym of P. harinasutai, because of their morphological and molecular similarities. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  3. Validation and norming of the Intelligibility in Context Scale in Northern Viet Nam.

    PubMed

    Phạm, Ben; McLeod, Sharynne; Harrison, Linda J

    2017-01-01

    Vietnamese is one of the 20 most commonly spoken languages in the world; however, there are no standardised tools to assess Vietnamese children's speech. This study aimed to validate and norm the Vietnamese version of the Intelligibility in Context Scale (ICS-VN). Data were collected from parents of 181 children (aged 2;0-5;11) living in Ha Noi, Northern Viet Nam. The mean ICS-VN score was 4.43 (out of a maximum of 5), indicating that children were 'usually' to 'always' intelligible; however, item-level scores demonstrated significant differences between communication partners. Children with parental concerns about speech and language had significantly lower mean scores than children without parental concerns. Scores also differed by children's age, parents' occupation and mothers' education level but not by sex of child or fathers' education level. The ICS-VN had good psychometric properties indicating it to be a valid tool for use with Vietnamese-speaking children in Northern Viet Nam.

  4. Prevalence of latent tuberculous infection among adults in the general population of Ca Mau, Viet Nam.

    PubMed

    Marks, G B; Nhung, N V; Nguyen, T A; Hoa, N B; Khoa, T H; Son, N V; Phuong, N T B; Tin, D M; Ho, J; Fox, G J

    2018-03-01

    The study was conducted in a randomly selected sample of persons aged 15 years living in Ca Mau Province, southern Viet Nam. To estimate the prevalence of latent tuberculous infection (LTBI) in the general adult population of this province of Viet Nam. The secondary objective was to examine age and sex differences in prevalence. A cross-sectional survey was conducted in a cluster-random sample of the population. Clusters were subcommunes. The presence of LTBI was assessed using the QuantiFERON®-TB Gold In-Tube test system. QuantiFERON tests were performed among 1319 persons aged 15 years (77.7% of those selected). The overall prevalence of positive tests was 36.8% (95%CI 33.4-40.3). The prevalence of a positive test was lower in females than in males (31.0% vs. 44.7%, OR 0.57, 95%CI 0.45-0.72, P < 0.0001). The prevalence of positive tests increased with increasing age quintile (P < 0.0001). More than one third of the general adult population in a province in southern Viet Nam have evidence of LTBI. Although LTBI prevalence is higher in males, the sex difference is not as great as that for TB notification rates.

  5. Matrix Effects in SIMS Analysis of Hydrogen in Nominally Anhydrous Minerals (NAMs)

    NASA Astrophysics Data System (ADS)

    Mosenfelder, J. L.; Rossman, G. R.

    2014-12-01

    Accurate analysis of trace H in NAMs has become important with recognition that even small amounts of H influence geochemical and geophysical processes. FTIR and SIMS can measure concentrations down to ~1 ppmw H2O. However, a major limitation is that they rely on standards calibrated with other methods. SIMS matrix effects for H in NAMs are poorly constrained, but are likely dominated by differences in mean atomic mass. Here we use volatile-free molar weight (VFMW) normalized to one O/mol as a proxy for this parameter [cf. 1]. Our goal is to constrain SIMS matrix effects by combining our work on olivine [2], pyroxene [3], and feldspar [4] with new data on kyanite, zircon, and 37 garnets (pyropes, grossulars, spessartines, and andradites), while critically evaluating absolute calibrations of IR absorption coefficients (ɛi) for H in NAMs. All of these NAMs taken together span a wider range in VFMW (~32-45) than in previous comparisons [5, 6] concentrating only on olivine, pyroxene, and pyrope-rich garnet (VFMW ~ 34-37). Our results and conclusions include the following: 1) SIMS-FTIR comparisons demonstrate that ɛi is wavenumber dependent for feldspar, zircon, grossular, and clinopyroxene, in accord with theory and empirical calibrations on hydrous materials. On the other hand, a factor of 3 difference in ɛi for H defects in olivine [7] is unsupported by our data [2]. 2) Calibration slopes (for plots of ppmw H2O vs. 16OH/30Si × SiO2) correlate positively with VFMW, an effect not discerned in previous work [6]. This result is also opposite to a study demonstrating a negative correlation for hydrous phases and glasses [1]. This discrepancy may be related to differences in analytical methods (e.g., Cs+ vs. O- primary beam, collection of OH- versus H+). 3) Scatter in the trend of calibration slopes vs. VFMW is likely due to uncertainties in ɛi. Another possible factor is the structure of the matrix, which can affect the kinetic energy of cascade collisions leading to

  6. Infrared spectroscopy of matrix-isolated polycyclic aromatic hydrocarbon cations. 2. The members of the thermodynamically most favorable series through coronene

    NASA Technical Reports Server (NTRS)

    Hudgins, D. M.; Allamandola, L. J.

    1995-01-01

    Gaseous, ionized polycyclic aromatic hydrocarbons (PAHs) are thought to be responsible for a very common family of interstellar infrared emission bands. Here the near- and mid-infrared spectra of the cations of the five most thermodynamically favored PAHs up to coronene:phenanthrene, pyrene, benzo[e]pyrene, benzo[ghi]perylene, and coronene, are presented to test this hypothesis. For those molecules that have been studied previously (pyrene, pyrene-d10, and coronene), band positions and relative intensities are in agreement. In all of these cases we report additional features. Absolute integrated absorbance values are given for the phenanthrene, perdeuteriophenanthrene, pyrene, benzo[ghi]perylene, and coronene cations. With the exception of coronene, the cation bands corresponding to the CC modes are typically 2-5 times more intense than those of the CH out-of-plane bending vibrations. For the cations, the CC stretching and CH in-plane bending modes give rise to bands that are an order of magnitude stronger than those of the neutral species, and the CH out-of-plane bends produce bands that are 5-20 times weaker than those of the neutral species. This behavior is similar to that found in most other PAH cations studied to date. The astronomical implications of these PAH cation spectra are also discussed.

  7. Infrared Spectroscopy of Matrix-Isolated Polycyclic Aromatic Hydrocarbon Cations. Part 2; The Members of the Thermodynamically Most Favorable Series through Coronene

    NASA Technical Reports Server (NTRS)

    Hudgins, D. M.; Allamandola, L. J.

    1995-01-01

    Gaseous, ionized polycyclic aromatic hydrocarbons (PAHS) are thought to be responsible for a very common family of interstellar infrared emission bands. Here the near- and mid-infrared spectra of the cations of the five most thermodynamically favored PAHs up to coronene: phenanthrene, pyrene, benzo[e]pyrene, benzo-[ghi]perylene, and coronene, are presented to test this hypothesis. For those molecules that have been studied previously (pyrene, pyrene-d(sub 10), and coronene), band positions and relative intensities are in agreement. In all of these cases we report additional features. Absolute integrated absorbance values are given for the phenanthrene, perdeuteriophenanthrene, pyrene, benzo[ghi]perylene, and coronene cations. With the exception of coronene, the cation bands corresponding to the CC modes are typically 2-5 times more intense than those of the CH out-of-plane bending vibrations. For the cations, the CC stretching and CH in-plane bending modes give rise to bands that are an order of magnitude stronger than those of the neutral species, and the CH out-of-plane bends produce bands that are 5-20 times weaker than those of the neutral species. This behavior is similar to that found in most other PAH cations studied to date. The astronomical implications of these PAH cation spectra are also discussed.

  8. Infrared Spectroscopy of Matrix-Isolated Polycyclic Aromatic Hydrocarbon Cations

    NASA Technical Reports Server (NTRS)

    Hudgins, D. M.; Allamandola, L. J.

    1995-01-01

    Gaseous, ionized polycyclic aromatic hydrocarbons (PAHs) are thought to be responsible for a very common family of interstellar infrared emission bands. Here the near- and mid-infrared spectra of the cations of the five most thermodynamically favored PAHs up to coronene: phenanthrene, pyrene, benzo(e)pyrene, benzo-(ghi)perylene, and coronene, are presented to test this hypothesis. For those molecules that have been studied previously (pyrene, pyrene-d(sub 10), and coronene), band positions and relative intensities are in agreement. In all of these cases we report additional features. Absolute integrated absorbance values are given for the phenanthrene, perdeuteriophenanthrene, pyrene, benzo(ghi]perylene, and coronene cations. With the exception of coronene, the cation bands corresponding to the CC modes are typically 2-5 times more intense than those of the CH out-of-plane bending vibrations. For the cations, the CC stretching and CH in-plane bending modes give rise to bands that are an order of magnitude stronger than those of the neutral species, and the CH out-of-plane bends produce bands that are 5-20 times weaker than those of the neutral species. This behavior is similar to that found in most other PAH cations studied to date. The astronomical implications of these PAH cation spectra are also discussed.

  9. Compiling mortality statistics from civil registration systems in Viet Nam: the long road ahead.

    PubMed

    Rao, Chalapati; Osterberger, Brigitta; Anh, Tran Dam; MacDonald, Malcolm; Chúc, Nguyen Thi Kim; Hill, Peter S

    2010-01-01

    Accurate mortality statistics, needed for population health assessment, health policy and research, are best derived from data in vital registration systems. However, mortality statistics from vital registration systems are not available for several countries including Viet Nam. We used a mixed methods case study approach to assess vital registration operations in 2006 in three provinces in Viet Nam (Hòa Bình, Thùa Thiên-Hué and Bình Duong), and provide recommendations to strengthen vital registration systems in the country. For each province we developed life tables from population and mortality data compiled by sex and age group. Demographic methods were used to estimate completeness of death registration as an indicator of vital registration performance. Qualitative methods (document review, key informant interviews and focus group discussions) were used to assess administrative, technical and societal aspects of vital registration systems. Completeness of death registration was low in all three provinces. Problems were identified with the legal framework for registration of early neonatal deaths and deaths of temporary residents or migrants. The system does not conform to international standards for reporting cause of death or for recording detailed statistics by age, sex and cause of death. Capacity-building along with an intersectoral coordination committee involving the Ministries of Justice and Health and the General Statistics Office would improve the vital registration system, especially with regard to procedures for death registration. There appears to be strong political support for sentinel surveillance systems to generate reliable mortality statistics in Viet Nam.

  10. A rapid assessment and response approach for socially marketed nutrition commodities in Viet Nam.

    PubMed

    Turk, Tahir; Quang, Nguyen Dinh; Nga, Tran Thuy; Phuong, Huynh; Tung, Le Van Anh; Trang, Vu Hoang

    2017-01-01

    The leading cause of death in children in developing countries is protein-energy malnutrition. In Viet Nam, 25.9% of children under 5 experience stunted growth and 6.6% are moderately wasted. Iron deficiency anaemia and vitamin A deficiency contribute to these and other malnutrition conditions. Given these factors, more evidence based approaches are required to improve understanding of current attitudes, opinions and behaviours of mothers with young children, in order to operationalise social marketing of nutrition commodities in Viet Nam. A literature review supported a rapid assessment and response method involving semi-structured interviews with 77 stakeholders and focus group discussions with 80 program beneficiaries from four geographic locations in the north and south of Viet Nam. Discussion agendas were developed to address key program issues with grounded theory utilized for data analysis. Data analysis highlighted challenges and opportunities within the six Ps of social marketing: Supply and demand side issues included: cost and the quality of products, the limited scale of interventions and promotional activities. Policy issues identified related to current policies that inhibited the broader promotion and distribution of micronutrient products, and opportunities for improved dialogue with policy partners. Partnerships further emphasized the need for public private partnerships to support the social change process. Implications for theory, policy, and practice indicates that rapid assessment and response is a cost-effective, pragmatic method of public health research, in resource constrained settings, to explore policies and behaviours amenable to change and build stakeholder engagement in the program.

  11. Seismic while drilling: Operational experiences in Viet Nam

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

    Jackson, M.; Einchcomb, C.

    1997-03-01

    The BP/Statoil alliance in Viet Nam has used seismic while drilling on four wells during the last two years. Three wells employed the Western Atlas Tomex system, and the last well, Schlumberger`s SWD system. Perceived value of seismic while drilling (SWD) lies in being able to supply real-time data linking drill bit position to a seismic picture of the well. However, once confidence in equipment and methodology is attained, SWD can influence well design and planning associated with drilling wells. More important, SWD can remove uncertainty when actually drilling wells, allowing risk assessment to be carried out more accurately andmore » confidently.« less

  12. Symptoms and risk factors for stroke in a community-based observational sample in Viet Nam.

    PubMed

    Fitzpatrick, Annette L; Ngo, Quang Van; Ly, Kiet A; Ton, Thanh G N; Longstreth, W T; Vo, Tung T; Heitzinger, Kristen; Pham, Chien H; Tirschwell, David L

    2012-09-01

    Viet Nam is experiencing a health transition from infectious to chronic disease. Data on cardiovascular diseases, including strokes, are limited. Data were randomly collected from six communities in Da Nang, Viet Nam, on participant demographics, medical history, blood pressure, anthropometrics and health behavior using World Health Organization (WHO) guidelines. Stroke symptoms were collected by self-report with the standardized Questionnaire for Verifying Stroke Free Status. Multivariate logistic regression was used to identify factors associated with the presence of stroke symptoms. One thousand six hundred and twenty one adults were examined with a mean age of 52.0 years (± 12.5 years), of which 56.1% were women. 27.3% of the participants were found to have hypertension, 26.2% used tobacco, and 16.1% were overweight. More than two-thirds of the participants with hypertension were unaware of their condition. Almost one fourth of the participants were identified by the questionnaire as previously experiencing at least one stroke symptom. Age, rural residence, and education were associated with the presence of stroke symptoms. Models adjusted for demographics found hypertension, high cholesterol, reported severe chest pain, former smoking, and being overweight to be associated with a higher prevalence of stroke symptoms. The high frequency of stroke symptoms in Da Nang calls for further evaluation and interventions to reduce hypertension and other risk factors for chronic disease in Viet Nam and other health transition countries.

  13. Structure, stratigraphy and petroleum geology of the south east Nam Con Son Basin, offshore Vietnam

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

    Fraser, A.J.; Matthews, S.J.; Lowe, S.

    1996-12-31

    Recent exploration of the south east Nam Con Son Basin, offshore Vietnam, by BP in alliance with Statoil has involved acquisition of new seismic and well data. These new data have allowed re-evaluation of the tectono-stratigraphic development and petroleum geology, and have provided additional constraints on the regional tectonic evolution. The offshore Vietnamese basins have evolved in response to the complex relative motions of Indochina, Peninsular Malaysia, Borneo and the South China Sea during the Cenozoic. On the regional scale these motions have been accommodated by strike-slip fault development, rifting and contraction. In the Nam Con Son Basin these motionsmore » have interacted in different ways from the Palaeogene to recent. Two rifting episodes are recognized; a Palaeogene phase dominated by E-W trending extensional faults, and a Miocene phase dominated by N-S to NE-SW trending faults. The structural evolution is complicated by a pulse of mild contraction during the Middle Miocene. The sedimentary fill of the basin evolves from continental fluvio-lacustrine in the Palaeogene through to fully marine following the second phase of rifting in the Miocene. This pulsed structural and stratigraphic evolution has resulted in basinwide deposition of source, reservoir and seal facies, and produced a variety of potential trapping styles. This paper describes the hydrocarbon habitat of the south east Nam Con Son Basin within the context of the regional tectono-stratigraphic model.« less

  14. Structure, stratigraphy and petroleum geology of the south east Nam Con Son Basin, offshore Vietnam

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

    Fraser, A.J.; Matthews, S.J.; Lowe, S.

    1996-01-01

    Recent exploration of the south east Nam Con Son Basin, offshore Vietnam, by BP in alliance with Statoil has involved acquisition of new seismic and well data. These new data have allowed re-evaluation of the tectono-stratigraphic development and petroleum geology, and have provided additional constraints on the regional tectonic evolution. The offshore Vietnamese basins have evolved in response to the complex relative motions of Indochina, Peninsular Malaysia, Borneo and the South China Sea during the Cenozoic. On the regional scale these motions have been accommodated by strike-slip fault development, rifting and contraction. In the Nam Con Son Basin these motionsmore » have interacted in different ways from the Palaeogene to recent. Two rifting episodes are recognized; a Palaeogene phase dominated by E-W trending extensional faults, and a Miocene phase dominated by N-S to NE-SW trending faults. The structural evolution is complicated by a pulse of mild contraction during the Middle Miocene. The sedimentary fill of the basin evolves from continental fluvio-lacustrine in the Palaeogene through to fully marine following the second phase of rifting in the Miocene. This pulsed structural and stratigraphic evolution has resulted in basinwide deposition of source, reservoir and seal facies, and produced a variety of potential trapping styles. This paper describes the hydrocarbon habitat of the south east Nam Con Son Basin within the context of the regional tectono-stratigraphic model.« less

  15. Using lot quality-assurance sampling and area sampling to identify priority areas for trachoma control: Viet Nam.

    PubMed

    Myatt, Mark; Mai, Nguyen Phuong; Quynh, Nguyen Quang; Nga, Nguyen Huy; Tai, Ha Huy; Long, Nguyen Hung; Minh, Tran Hung; Limburg, Hans

    2005-10-01

    To report on the use of lot quality-assurance sampling (LQAS) surveys undertaken within an area-sampling framework to identify priority areas for intervention with trachoma control activities in Viet Nam. The LQAS survey method for the rapid assessment of the prevalence of active trachoma was adapted for use in Viet Nam with the aim of classifying individual communes by the prevalence of active trachoma among children in primary school. School-based sampling was used; school sites to be sampled were selected using an area-sampling approach. A total of 719 communes in 41 districts in 18 provinces were surveyed. Survey staff found the LQAS survey method both simple and rapid to use after initial problems with area-sampling methods were identified and remedied. The method yielded a finer spatial resolution of prevalence than had been previously achieved in Viet Nam using semiquantitative rapid assessment surveys and multistage cluster-sampled surveys. When used with area-sampling techniques, the LQAS survey method has the potential to form the basis of survey instruments that can be used to efficiently target resources for interventions against active trachoma. With additional work, such methods could provide a generally applicable tool for effective programme planning and for the certification of the elimination of trachoma as a blinding disease.

  16. Positive and negative metacognitions about alcohol use among university students: Psychometric properties of the PAMS and NAMS French versions.

    PubMed

    Gierski, Fabien; Spada, Marcantonio M; Fois, Eveline; Picard, Aurélie; Naassila, Mickaël; Van der Linden, Martial

    2015-08-01

    Metacognitions about the positive and negative effects of alcohol use have been associated with various patterns of drinking. The aim of the present study was to validate French versions of the Positive Alcohol Metacognitions Scale (PAMS) and the Negative Alcohol Metacognitions Scale (NAMS) developed by Spada and Wells (2008, Addict. Behav. 33, 515) and to investigate the relationship between metacognitions and patterns of alcohol use among university students. Responses of 1600 university students who participated in an internet survey-based study on alcohol use were submitted to confirmatory (N=800, mean age 20.40 years, 45.50% male) and exploratory (N=800, mean age 20.34 years, 45.38% male) factor analyses in two separate samples. Alcohol use, binge drinking and mood were also assessed. In line with the original versions of the scales, results provided support for a two-factor structure of the French PAMS and NAMS. Both scales revealed adequate internal reliability. Good temporal stability was found for the two factors of the NAMS, whereas one factor of the PAMS showed weakness across time. Predictive validity revealed that negative alcohol metacognitions about the uncontrollability of alcohol use were found to be consistently associated with alcohol use and binge drinking, whereas positive metacognitions about alcohol use were found to be differentially associated with alcohol use and binge drinking. The French versions of the PAMS and NAMS exhibited suitable psychometric properties. This study also emphasized the role of metacognitions about alcohol use in drinking behaviour among university students. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  17. Survey of Food-hygiene Practices at Home and Childhood Diarrhoea in Hanoi, Viet Nam

    PubMed Central

    Takanashi, Kumiko; Chonan, Yuko; Quyen, Dao To; Khan, Nguyen Cong; Poudel, Krishna C.

    2009-01-01

    A cross-sectional study was conducted to investigate the potential factors of food-hygiene practices of mothers on the prevalence of diarrhoea among their children. Mothers who had children aged 6 months–5 years were recruited in a hamlet in Viet Nam. The food-hygiene practices included hand-washing, method of washing utensils, separation of utensils for raw and cooked food, and the location where foods were prepared for cooking. A face-to-face interview was conducted, and data on 206 mothers were analyzed. The risk of diarrhoea was significantly higher among children whose mothers prepared food for cooking somewhere other than the table (typically on the ground) compared to children whose mothers prepared food on the table (adjusted odds ratio=2.85, 95% confidence interval 1.11–7.28). The results indicate that food-hygiene practices of mothers, such as avoiding preparing food for cooking on the ground, has a potential impact in preventing diarrhoea among children in Viet Nam. PMID:19902795

  18. Design and analysis of piston by Al-GHS 1300, Al-GHY 1250, Al-Si-C, A6061 and A4032 composite material: A review

    NASA Astrophysics Data System (ADS)

    Misra, Sheelam; Agrawal, Ankush

    2018-05-01

    Over the past decades the piston is designed to transfer force to the crank shaft through a piston rod by the expansion of gases in the cylinder. During working piston has to tolerate the cyclic gas pressure and the inertial forces, due to which the piston experiences fatigue damages such as piston side wear, piston head cracks and so on. Earlier pistons were made up of cast iron or aluminium due to their lightweight and high heat transfer rate. After some experiments it was noted that on heating cast iron expands due to which it covers the clearance level that comes to seize the engine. This paper aims to design a piston using composite material such as Al-GHS 1300, Al-GHY 1250, Al-Si-C, A6061 and A4032 that will differ the material and the characteristics of the traditional engine piston. This paper describes the thermal and mechanical properties of the piston when the study is done by taking five different materials.

  19. Origin of worldwide cultivated barley revealed by NAM-1 gene and grain protein content

    PubMed Central

    Wang, Yonggang; Ren, Xifeng; Sun, Dongfa; Sun, Genlou

    2015-01-01

    The origin, evolution, and distribution of cultivated barley provides powerful insights into the historic origin and early spread of agrarian culture. Here, population-based genetic diversity and phylogenetic analyses were performed to determine the evolution and origin of barley and how domestication and subsequent introgression have affected the genetic diversity and changes in cultivated barley on a worldwide scale. A set of worldwide cultivated and wild barleys from Asia and Tibet of China were analyzed using the sequences for NAM-1 gene and gene-associated traits-grain protein content (GPC). Our results showed Tibetan wild barley distinctly diverged from Near Eastern barley, and confirmed that Tibet is one of the origin and domestication centers for cultivated barley, and in turn supported a polyphyletic origin of domesticated barley. Comparison of haplotype composition among geographic regions revealed gene flow between Eastern and Western barley populations, suggesting that the Silk Road might have played a crucial role in the spread of genes. The GPC in the 118 cultivated and 93 wild barley accessions ranged from 6.73 to 12.35% with a mean of 9.43%. Overall, wild barley had higher averaged GPC (10.44%) than cultivated barley. Two unique haplotypes (Hap2 and Hap7) caused by a base mutations (at position 544) in the coding region of the NAM-1 gene might have a significant impact on the GPC. Single nucleotide polymorphisms and haplotypes of NAM-1 associated with GPC in barley could provide a useful method for screening GPC in barley germplasm. The Tibetan wild accessions with lower GPC could be useful for malt barley breeding. PMID:26483818

  20. Role of alcohol in hospitalized road trauma in Viet nam.

    PubMed

    Nguyen, Nam Phuong; Passmore, Jonathon; Tran, Lan Thi Ngoc; Luong, Anh Mai

    2013-01-01

    To assess the blood alcohol concentration (BAC; dependent variable) of patients with road traffic injuries (RTIs) presenting at 3 provincial and central hospitals in the Socialist Republic of Viet Nam by age, sex, and road user type (independent variables). This survey formed part of the Viet Nam Road Traffic Injury Prevention Project, funded by Bloomberg Philanthropies. RTIs are a leading cause of death and disability in Viet Nam, with 14,690 deaths and 143,940 injuries reported by the Ministry of Health (MOH) in 2010. Research estimates suggest that motorcycle riders and passengers account for 60 percent of fatalities. Alcohol has long been suspected of being a leading cause of road traffic collisions and injuries. However, until now data on this relationship have been limited. A descriptive cross-sectional study measuring BAC in all consenting patients with RTIs presenting at 3 provincial or central hospitals between July 2009 and September 2010. All results were anonymous and summary information on key variables was sent to MOH and the World Health Organization (WHO) on a monthly basis. Of the 36,418 patients with RTIs presenting to these 3 hospitals between July 2009 and September 2010, BAC analysis was completed on 14,990 patients (41.2%), representing all patients with RTIs 15 years of age and above who consented to anonymous testing. BAC results ranged from 0 to 0.589 g/dL blood, with a mean of 0.0441 g/dL being the average concentration among all tested patients. Of all patients tested, 56.8 percent had no detectable alcohol in their system. Motorcycle riders were most commonly represented in the tested sample (70.7%), with 27.8 percent having a BAC above the legal limit (0.05 g/dL). Car or other vehicle drivers represented 2.7 percent of the sample, with 63.4 percent tested having a BAC above 0 g/dL, the legal limit for these road users. The results of this preliminary study indicate that 29.1 percent of all car drivers and motorcycle riders presenting at

  1. High-risk and multiple human papillomavirus infections among married women in Can Tho, Viet Nam.

    PubMed

    Vu, Lan Thi Hoang

    2012-07-01

    The two currently licensed human papillomavirus (HPV) vaccines are highly efficacious in preventing cervical pre-cancers related to HPV 6, 11, 16 and 18. Before implementing a large-scale HPV vaccine campaign in Viet Nam, information about the prevalence of infection with the HPV vaccine types is required. This study was done in Can Tho, the province with the highest prevalence of cervical cancer in the south of Viet Nam, to explore the distribution of other high-risk types of HPV among married women in this province. The study employed a cross-sectional design with multistage sampling. A total of 1000 participants were randomly selected, interviewed and given gynaecological examinations. HPV infection status and HPV genotyping test were completed for all participants. A broad spectrum of HPV types was reported in this study. The prevalence of cases infected with HPV 16 and/or 18 was 7%; the prevalence of cases infected with other high-risk HPV types was 6%. The highest prevalence for single and multiple infections, as well as for high-risk infections, was reported for the youngest age group (less than 30 years). While it is relevant to implement an HPV vaccine campaign in Viet Nam due to the high prevalence of infection with HPV 16 and/or 18, it is important to note that one can be infected with multiple types of HPV. Vaccination does not protect against all types of high-risk HPV. Future vaccine campaigns should openly disclose this information to women receiving vaccines.

  2. Using lot quality-assurance sampling and area sampling to identify priority areas for trachoma control: Viet Nam.

    PubMed Central

    Myatt, Mark; Mai, Nguyen Phuong; Quynh, Nguyen Quang; Nga, Nguyen Huy; Tai, Ha Huy; Long, Nguyen Hung; Minh, Tran Hung; Limburg, Hans

    2005-01-01

    OBJECTIVE: To report on the use of lot quality-assurance sampling (LQAS) surveys undertaken within an area-sampling framework to identify priority areas for intervention with trachoma control activities in Viet Nam. METHODS: The LQAS survey method for the rapid assessment of the prevalence of active trachoma was adapted for use in Viet Nam with the aim of classifying individual communes by the prevalence of active trachoma among children in primary school. School-based sampling was used; school sites to be sampled were selected using an area-sampling approach. A total of 719 communes in 41 districts in 18 provinces were surveyed. FINDINGS: Survey staff found the LQAS survey method both simple and rapid to use after initial problems with area-sampling methods were identified and remedied. The method yielded a finer spatial resolution of prevalence than had been previously achieved in Viet Nam using semiquantitative rapid assessment surveys and multistage cluster-sampled surveys. CONCLUSION: When used with area-sampling techniques, the LQAS survey method has the potential to form the basis of survey instruments that can be used to efficiently target resources for interventions against active trachoma. With additional work, such methods could provide a generally applicable tool for effective programme planning and for the certification of the elimination of trachoma as a blinding disease. PMID:16283052

  3. Improving the diagnosis of pulmonary tuberculosis in HIV-infected individuals in Ho Chi Minh City, Viet Nam.

    PubMed

    Nguyen, D T M; Hung, N Q; Giang, L T; Dung, N H; Lan, N T N; Lan, N N; Yen, N T B; Bang, N D; Ngoc, D V; Trinh, L T T; Beasley, R P; Ford, C E; Hwang, L-Y; Graviss, E A

    2011-11-01

    District 6, An Hoa Clinic in Ho Chi Minh City (HCMC), Viet Nam. To evaluate the performance of various algorithms in tuberculosis (TB) screening and diagnosis in a human immunodeficiency virus (HIV) infected population in HCMC, Viet Nam. A cross-sectional study of 397 consecutive HIV-infected patients seeking care at the An Hoa Clinic from August 2009 to June 2010. Data on participant demographics, clinical status, chest radiography (CXR) and laboratory results were collected. A multiple logistic regression model was developed to assess the association of covariates and pulmonary TB (PTB). The prevalence of sputum culture-confirmed PTB, acid-fast bacilli (AFB) positive TB, and multidrugresistant TB among the 397 HIV-infected patients was respectively 7%, 2%, and 0.3%. Adjusted odds ratios for low CD4+ cell count, positive sputum smear, and CXR to positive sputum culture were respectively 3.17, 32.04 and 4.28. Clinical findings alone had poor sensitivity, but combining CD4+ cell count, AFB sputum smear and CXR had a more accurate diagnostic performance. Results suggest that symptom screening had poor clinical performance, and support the routine use of sputum culture to improve the detection of TB disease in HIV-infected individuals in Viet Nam. However, when routine sputum culture is not available, an algorithm combining CD4+ cell count, AFB sputum smear and CXR is recommended for diagnosing PTB.

  4. CH-TRU Waste Content Codes (CH-TRUCON)

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

    Washington TRU Solutions LLC

    2007-08-15

    The CH-TRU Waste Content Codes (CH-TRUCON) document describes the inventory of the U.S. Department of Energy (DOE) CH-TRU waste within the transportation parameters specified by the Contact-Handled Transuranic Waste Authorized Methods for Payload Control (CH-TRAMPAC). The CH-TRAMPAC defines the allowable payload for the Transuranic Package Transporter-II (TRUPACT-II) and HalfPACT packagings. This document is a catalog of TRUPACT-II and HalfPACT authorized contents and a description of the methods utilized to demonstrate compliance with the CH-TRAMPAC. A summary of currently approved content codes by site is presented in Table 1. The CH-TRAMPAC describes "shipping categories" that are assigned to each payload container.more » Multiple shipping categories may be assigned to a single content code. A summary of approved content codes and corresponding shipping categories is provided in Table 2, which consists of Tables 2A, 2B, and 2C. Table 2A provides a summary of approved content codes and corresponding shipping categories for the "General Case," which reflects the assumption of a 60-day shipping period as described in the CH-TRAMPAC and Appendix 3.4 of the CH-TRU Payload Appendices. For shipments to be completed within an approximately 1,000-mile radius, a shorter shipping period of 20 days is applicable as described in the CH-TRAMPAC and Appendix 3.5 of the CH-TRU Payload Appendices. For shipments to WIPP from Los Alamos National Laboratory (LANL), Nevada Test Site, and Rocky Flats Environmental Technology Site, a 20-day shipping period is applicable. Table 2B provides a summary of approved content codes and corresponding shipping categories for "Close-Proximity Shipments" (20-day shipping period). For shipments implementing the controls specified in the CH-TRAMPAC and Appendix 3.6 of the CH-TRU Payload Appendices, a 10-day shipping period is applicable. Table 2C provides a summary of approved content codes and corresponding shipping categories for "Controlled

  5. CH-TRU Waste Content Codes (CH-TRUCON)

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

    Washington TRU Solutions LLC

    2007-06-15

    The CH-TRU Waste Content Codes (CH-TRUCON) document describes the inventory of the U.S. Department of Energy (DOE) CH-TRU waste within the transportation parameters specified by the Contact-Handled Transuranic Waste Authorized Methods for Payload Control (CH-TRAMPAC). The CH-TRAMPAC defines the allowable payload for the Transuranic Package Transporter-II (TRUPACT-II) and HalfPACT packagings. This document is a catalog of TRUPACT-II and HalfPACT authorized contents and a description of the methods utilized to demonstrate compliance with the CH-TRAMPAC. A summary of currently approved content codes by site is presented in Table 1. The CH-TRAMPAC describes "shipping categories" that are assigned to each payload container.more » Multiple shipping categories may be assigned to a single content code. A summary of approved content codes and corresponding shipping categories is provided in Table 2, which consists of Tables 2A, 2B, and 2C. Table 2A provides a summary of approved content codes and corresponding shipping categories for the "General Case," which reflects the assumption of a 60-day shipping period as described in the CH-TRAMPAC and Appendix 3.4 of the CH-TRU Payload Appendices. For shipments to be completed within an approximately 1,000-mile radius, a shorter shipping period of 20 days is applicable as described in the CH-TRAMPAC and Appendix 3.5 of the CH-TRU Payload Appendices. For shipments to WIPP from Los Alamos National Laboratory (LANL), Nevada Test Site, and Rocky Flats Environmental Technology Site, a 20-day shipping period is applicable. Table 2B provides a summary of approved content codes and corresponding shipping categories for "Close-Proximity Shipments" (20-day shipping period). For shipments implementing the controls specified in the CH-TRAMPAC and Appendix 3.6 of the CH-TRU Payload Appendices, a 10-day shipping period is applicable. Table 2C provides a summary of approved content codes and corresponding shipping categories for "Controlled

  6. CH-TRU Waste Content Codes (CH-TRUCON)

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

    Washington TRU Solutions LLC

    2007-09-20

    The CH-TRU Waste Content Codes (CH-TRUCON) document describes the inventory of the U.S. Department of Energy (DOE) CH-TRU waste within the transportation parameters specified by the Contact-Handled Transuranic Waste Authorized Methods for Payload Control (CH-TRAMPAC). The CH-TRAMPAC defines the allowable payload for the Transuranic Package Transporter-II (TRUPACT-II) and HalfPACT packagings. This document is a catalog of TRUPACT-II and HalfPACT authorized contents and a description of the methods utilized to demonstrate compliance with the CH-TRAMPAC. A summary of currently approved content codes by site is presented in Table 1. The CH-TRAMPAC describes "shipping categories" that are assigned to each payload container.more » Multiple shipping categories may be assigned to a single content code. A summary of approved content codes and corresponding shipping categories is provided in Table 2, which consists of Tables 2A, 2B, and 2C. Table 2A provides a summary of approved content codes and corresponding shipping categories for the "General Case," which reflects the assumption of a 60-day shipping period as described in the CH-TRAMPAC and Appendix 3.4 of the CH-TRU Payload Appendices. For shipments to be completed within an approximately 1,000-mile radius, a shorter shipping period of 20 days is applicable as described in the CH-TRAMPAC and Appendix 3.5 of the CH-TRU Payload Appendices. For shipments to WIPP from Los Alamos National Laboratory (LANL), Nevada Test Site, and Rocky Flats Environmental Technology Site, a 20-day shipping period is applicable. Table 2B provides a summary of approved content codes and corresponding shipping categories for "Close-Proximity Shipments" (20-day shipping period). For shipments implementing the controls specified in the CH-TRAMPAC and Appendix 3.6 of the CH-TRU Payload Appendices, a 10-day shipping period is applicable. Table 2C provides a summary of approved content codes and corresponding shipping categories for "Controlled

  7. CH-TRU Waste Content Codes (CH-TRUCON)

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

    Washington TRU Solutions LLC

    2006-06-20

    The CH-TRU Waste Content Codes (CH-TRUCON) document describes the inventory of the U.S. Department of Energy (DOE) CH-TRU waste within the transportation parameters specified by the Contact-Handled Transuranic Waste Authorized Methods for Payload Control (CH-TRAMPAC). The CH-TRAMPAC defines the allowable payload for the Transuranic Package Transporter-II (TRUPACT-II) and HalfPACT packagings. This document is a catalog of TRUPACT-II and HalfPACT authorized contents and a description of the methods utilized to demonstrate compliance with the CH-TRAMPAC. A summary of currently approved content codes by site is presented in Table 1. The CH-TRAMPAC describes "shipping categories" that are assigned to each payload container.more » Multiple shipping categories may be assigned to a single content code. A summary of approved content codes and corresponding shipping categories is provided in Table 2, which consists of Tables 2A, 2B, and 2C. Table 2A provides a summary of approved content codes and corresponding shipping categories for the "General Case," which reflects the assumption of a 60-day shipping period as described in the CH-TRAMPAC and Appendix 3.4 of the CH-TRU Payload Appendices. For shipments to be completed within an approximately 1,000-mile radius, a shorter shipping period of 20 days is applicable as described in the CH-TRAMPAC and Appendix 3.5 of the CH-TRU Payload Appendices. For shipments to WIPP from Los Alamos National Laboratory (LANL), Nevada Test Site, and Rocky Flats Environmental Technology Site, a 20-day shipping period is applicable. Table 2B provides a summary of approved content codes and corresponding shipping categories for "Close-Proximity Shipments" (20-day shipping period). For shipments implementing the controls specified in the CH-TRAMPAC and Appendix 3.6 of the CH-TRU Payload Appendices, a 10-day shipping period is applicable. Table 2C provides a summary of approved content codes and corresponding shipping categories for "Controlled

  8. CH-TRU Waste Content Codes (CH-TRUCON)

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

    Washington TRU Solutions LLC

    2006-01-18

    The CH-TRU Waste Content Codes (CH-TRUCON) document describes the inventory of the U.S. Department of Energy (DOE) CH-TRU waste within the transportation parameters specified by the Contact-Handled Transuranic Waste Authorized Methods for Payload Control (CH-TRAMPAC). The CH-TRAMPAC defines the allowable payload for the Transuranic Package Transporter-II (TRUPACT-II) and HalfPACT packagings. This document is a catalog of TRUPACT-II and HalfPACT authorized contents and a description of the methods utilized to demonstrate compliance with the CH-TRAMPAC. A summary of currently approved content codes by site is presented in Table 1. The CH-TRAMPAC describes "shipping categories" that are assigned to each payload container.more » Multiple shipping categories may be assigned to a single content code. A summary of approved content codes and corresponding shipping categories is provided in Table 2, which consists of Tables 2A, 2B, and 2C. Table 2A provides a summary of approved content codes and corresponding shipping categories for the "General Case," which reflects the assumption of a 60-day shipping period as described in the CH-TRAMPAC and Appendix 3.4 of the CH-TRU Payload Appendices. For shipments to be completed within an approximately 1,000-mile radius, a shorter shipping period of 20 days is applicable as described in the CH-TRAMPAC and Appendix 3.5 of the CH-TRU Payload Appendices. For shipments to WIPP from Los Alamos National Laboratory (LANL), Nevada Test Site, and Rocky Flats Environmental Technology Site, a 20-day shipping period is applicable. Table 2B provides a summary of approved content codes and corresponding shipping categories for "Close-Proximity Shipments" (20-day shipping period). For shipments implementing the controls specified in the CH-TRAMPAC and Appendix 3.6 of the CH-TRU Payload Appendices, a 10-day shipping period is applicable. Table 2C provides a summary of approved content codes and corresponding shipping categories for "Controlled

  9. CH-TRU Waste Content Codes (CH-TRUCON)

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

    Washington TRU Solutions LLC

    2006-08-15

    The CH-TRU Waste Content Codes (CH-TRUCON) document describes the inventory of the U.S. Department of Energy (DOE) CH-TRU waste within the transportation parameters specified by the Contact-Handled Transuranic Waste Authorized Methods for Payload Control (CH-TRAMPAC). The CH-TRAMPAC defines the allowable payload for the Transuranic Package Transporter-II (TRUPACT-II) and HalfPACT packagings. This document is a catalog of TRUPACT-II and HalfPACT authorized contents and a description of the methods utilized to demonstrate compliance with the CH-TRAMPAC. A summary of currently approved content codes by site is presented in Table 1. The CH-TRAMPAC describes "shipping categories" that are assigned to each payload container.more » Multiple shipping categories may be assigned to a single content code. A summary of approved content codes and corresponding shipping categories is provided in Table 2, which consists of Tables 2A, 2B, and 2C. Table 2A provides a summary of approved content codes and corresponding shipping categories for the "General Case," which reflects the assumption of a 60-day shipping period as described in the CH-TRAMPAC and Appendix 3.4 of the CH-TRU Payload Appendices. For shipments to be completed within an approximately 1,000-mile radius, a shorter shipping period of 20 days is applicable as described in the CH-TRAMPAC and Appendix 3.5 of the CH-TRU Payload Appendices. For shipments to WIPP from Los Alamos National Laboratory (LANL), Nevada Test Site, and Rocky Flats Environmental Technology Site, a 20-day shipping period is applicable. Table 2B provides a summary of approved content codes and corresponding shipping categories for "Close-Proximity Shipments" (20-day shipping period). For shipments implementing the controls specified in the CH-TRAMPAC and Appendix 3.6 of the CH-TRU Payload Appendices, a 10-day shipping period is applicable. Table 2C provides a summary of approved content codes and corresponding shipping categories for "Controlled

  10. CH-TRU Waste Content Codes (CH-TRUCON)

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

    Washington TRU Solutions LLC

    2006-12-20

    The CH-TRU Waste Content Codes (CH-TRUCON) document describes the inventory of the U.S. Department of Energy (DOE) CH-TRU waste within the transportation parameters specified by the Contact-Handled Transuranic Waste Authorized Methods for Payload Control (CH-TRAMPAC). The CH-TRAMPAC defines the allowable payload for the Transuranic Package Transporter-II (TRUPACT-II) and HalfPACT packagings. This document is a catalog of TRUPACT-II and HalfPACT authorized contents and a description of the methods utilized to demonstrate compliance with the CH-TRAMPAC. A summary of currently approved content codes by site is presented in Table 1. The CH-TRAMPAC describes "shipping categories" that are assigned to each payload container.more » Multiple shipping categories may be assigned to a single content code. A summary of approved content codes and corresponding shipping categories is provided in Table 2, which consists of Tables 2A, 2B, and 2C. Table 2A provides a summary of approved content codes and corresponding shipping categories for the "General Case," which reflects the assumption of a 60-day shipping period as described in the CH-TRAMPAC and Appendix 3.4 of the CH-TRU Payload Appendices. For shipments to be completed within an approximately 1,000-mile radius, a shorter shipping period of 20 days is applicable as described in the CH-TRAMPAC and Appendix 3.5 of the CH-TRU Payload Appendices. For shipments to WIPP from Los Alamos National Laboratory (LANL), Nevada Test Site, and Rocky Flats Environmental Technology Site, a 20-day shipping period is applicable. Table 2B provides a summary of approved content codes and corresponding shipping categories for "Close-Proximity Shipments" (20-day shipping period). For shipments implementing the controls specified in the CH-TRAMPAC and Appendix 3.6 of the CH-TRU Payload Appendices, a 10-day shipping period is applicable. Table 2C provides a summary of approved content codes and corresponding shipping categories for "Controlled

  11. CH-TRU Waste Content Codes (CH-TRUCON)

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

    Washington TRU Solutions LLC

    2007-02-15

    The CH-TRU Waste Content Codes (CH-TRUCON) document describes the inventory of the U.S. Department of Energy (DOE) CH-TRU waste within the transportation parameters specified by the Contact-Handled Transuranic Waste Authorized Methods for Payload Control (CH-TRAMPAC). The CH-TRAMPAC defines the allowable payload for the Transuranic Package Transporter-II (TRUPACT-II) and HalfPACT packagings. This document is a catalog of TRUPACT-II and HalfPACT authorized contents and a description of the methods utilized to demonstrate compliance with the CH-TRAMPAC. A summary of currently approved content codes by site is presented in Table 1. The CH-TRAMPAC describes "shipping categories" that are assigned to each payload container.more » Multiple shipping categories may be assigned to a single content code. A summary of approved content codes and corresponding shipping categories is provided in Table 2, which consists of Tables 2A, 2B, and 2C. Table 2A provides a summary of approved content codes and corresponding shipping categories for the "General Case," which reflects the assumption of a 60-day shipping period as described in the CH-TRAMPAC and Appendix 3.4 of the CH-TRU Payload Appendices. For shipments to be completed within an approximately 1,000-mile radius, a shorter shipping period of 20 days is applicable as described in the CH-TRAMPAC and Appendix 3.5 of the CH-TRU Payload Appendices. For shipments to WIPP from Los Alamos National Laboratory (LANL), Nevada Test Site, and Rocky Flats Environmental Technology Site, a 20-day shipping period is applicable. Table 2B provides a summary of approved content codes and corresponding shipping categories for "Close-Proximity Shipments" (20-day shipping period). For shipments implementing the controls specified in the CH-TRAMPAC and Appendix 3.6 of the CH-TRU Payload Appendices, a 10-day shipping period is applicable. Table 2C provides a summary of approved content codes and corresponding shipping categories for "Controlled

  12. CH-TRU Waste Content Codes (CH-TRUCON)

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

    Washington TRU Solutions LLC

    2006-09-15

    The CH-TRU Waste Content Codes (CH-TRUCON) document describes the inventory of the U.S. Department of Energy (DOE) CH-TRU waste within the transportation parameters specified by the Contact-Handled Transuranic Waste Authorized Methods for Payload Control (CH-TRAMPAC). The CH-TRAMPAC defines the allowable payload for the Transuranic Package Transporter-II (TRUPACT-II) and HalfPACT packagings. This document is a catalog of TRUPACT-II and HalfPACT authorized contents and a description of the methods utilized to demonstrate compliance with the CH-TRAMPAC. A summary of currently approved content codes by site is presented in Table 1. The CH-TRAMPAC describes "shipping categories" that are assigned to each payload container.more » Multiple shipping categories may be assigned to a single content code. A summary of approved content codes and corresponding shipping categories is provided in Table 2, which consists of Tables 2A, 2B, and 2C. Table 2A provides a summary of approved content codes and corresponding shipping categories for the "General Case," which reflects the assumption of a 60-day shipping period as described in the CH-TRAMPAC and Appendix 3.4 of the CH-TRU Payload Appendices. For shipments to be completed within an approximately 1,000-mile radius, a shorter shipping period of 20 days is applicable as described in the CH-TRAMPAC and Appendix 3.5 of the CH-TRU Payload Appendices. For shipments to WIPP from Los Alamos National Laboratory (LANL), Nevada Test Site, and Rocky Flats Environmental Technology Site, a 20-day shipping period is applicable. Table 2B provides a summary of approved content codes and corresponding shipping categories for "Close-Proximity Shipments" (20-day shipping period). For shipments implementing the controls specified in the CH-TRAMPAC and Appendix 3.6 of the CH-TRU Payload Appendices, a 10-day shipping period is applicable. Table 2C provides a summary of approved content codes and corresponding shipping categories for "Controlled

  13. Neogene sequence stratigraphy, Nam Con Son Basin, offshore Vietnam

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

    McMillen, K.J.; Do Van Luu; Lee, E.K.

    1996-12-31

    An integrated well log, biostratigraphic, and seismic stratigraphic study of Miocene to Recent deltaic sediments deposited in the Nam Con Son Basin offshore from southern Vietnam shows the influence of eustacy and tectonics on sequence development. Sediments consist of Oligocene non-marine rift-basin fill (Cau Formation), early to middle Miocene tide-dominated delta plain to delta front sediments (TB 1.5 to TB 2.5, Due and Thong Formations), and late Miocene to Recent marine shelf sediments (TB. 2.6 to TB 3.1 0, Mang Cau, Nam Con Son, and Bien Dong Formations). Eustacy controlled the timing of key surfaces and sand distribution in themore » tectonically-quiet early Miocene. Tectonic effects on middle to late Miocene sequence development consist of thick transgressive systems tracts due to basin-wide subsidence and transgression, sand distribution in the basin center, and carbonate sedimentation on isolated fault blocks within the basin. Third-order sequence boundaries (SB) are identified by spore peaks, sand stacking patterns, and channel incision. In the basin center, widespread shale beds with coal occur above sequence boundaries followed by transgressive sandstone units. These TST sandstones merge toward the basin margin where they lie on older HST sandstones. Maximum flooding surfaces (MFS) have abundant marine microfossils and mangrove pollen, a change in sand stacking pattern, and often a strong seismic reflection with downlap. Fourth-order genetic-type sequences are also interpreted. The MFS is the easiest marker to identify and correlate on well logs. Fourth-order SB occur within these genetic units but are harder to identify and correlate.« less

  14. Neogene sequence stratigraphy, Nam Con Son Basin, offshore Vietnam

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

    McMillen, K.J.; Do Van Luu; Lee, E.K.

    1996-01-01

    An integrated well log, biostratigraphic, and seismic stratigraphic study of Miocene to Recent deltaic sediments deposited in the Nam Con Son Basin offshore from southern Vietnam shows the influence of eustacy and tectonics on sequence development. Sediments consist of Oligocene non-marine rift-basin fill (Cau Formation), early to middle Miocene tide-dominated delta plain to delta front sediments (TB 1.5 to TB 2.5, Due and Thong Formations), and late Miocene to Recent marine shelf sediments (TB. 2.6 to TB 3.1 0, Mang Cau, Nam Con Son, and Bien Dong Formations). Eustacy controlled the timing of key surfaces and sand distribution in themore » tectonically-quiet early Miocene. Tectonic effects on middle to late Miocene sequence development consist of thick transgressive systems tracts due to basin-wide subsidence and transgression, sand distribution in the basin center, and carbonate sedimentation on isolated fault blocks within the basin. Third-order sequence boundaries (SB) are identified by spore peaks, sand stacking patterns, and channel incision. In the basin center, widespread shale beds with coal occur above sequence boundaries followed by transgressive sandstone units. These TST sandstones merge toward the basin margin where they lie on older HST sandstones. Maximum flooding surfaces (MFS) have abundant marine microfossils and mangrove pollen, a change in sand stacking pattern, and often a strong seismic reflection with downlap. Fourth-order genetic-type sequences are also interpreted. The MFS is the easiest marker to identify and correlate on well logs. Fourth-order SB occur within these genetic units but are harder to identify and correlate.« less

  15. Swedish spring wheat varieties with the rare high grain protein allele of NAM-B1 differ in leaf senescence and grain mineral content.

    PubMed

    Asplund, Linnéa; Bergkvist, Göran; Leino, Matti W; Westerbergh, Anna; Weih, Martin

    2013-01-01

    Some Swedish spring wheat varieties have recently been shown to carry a rare wildtype (wt) allele of the gene NAM-B1, known to affect leaf senescence and nutrient retranslocation to the grain. The wt allele is believed to increase grain protein concentration and has attracted interest from breeders since it could contribute to higher grain quality and more nitrogen-efficient varieties. This study investigated whether Swedish varieties with the wt allele differ from varieties with one of the more common, non-functional alleles in order to examine the effect of the gene in a wide genetic background, and possibly explain why the allele has been retained in Swedish varieties. Forty varieties of spring wheat differing in NAM-B1 allele type were cultivated under controlled conditions. Senescence was monitored and grains were harvested and analyzed for mineral nutrient concentration. Varieties with the wt allele reached anthesis earlier and completed senescence faster than varieties with the non-functional allele. The wt varieties also had more ears, lighter grains and higher yields of P and K. Contrary to previous information on effects of the wt allele, our wt varieties did not have increased grain N concentration or grain N yield. In addition, temporal studies showed that straw length has decreased but grain N yield has remained unaffected over a century of Swedish spring wheat breeding. The faster development of wt varieties supports the hypothesis of NAM-B1 being preserved in Fennoscandia, with its short growing season, because of accelerated development conferred by the NAM-B1 wt allele. Although the possible effects of other gene actions were impossible to distinguish, the genetic resource of Fennoscandian spring wheats with the wt NAM-B1 allele is interesting to investigate further for breeding purposes.

  16. Swedish Spring Wheat Varieties with the Rare High Grain Protein Allele of NAM-B1 Differ in Leaf Senescence and Grain Mineral Content

    PubMed Central

    Asplund, Linnéa; Bergkvist, Göran; Leino, Matti W.; Westerbergh, Anna; Weih, Martin

    2013-01-01

    Some Swedish spring wheat varieties have recently been shown to carry a rare wildtype (wt) allele of the gene NAM-B1, known to affect leaf senescence and nutrient retranslocation to the grain. The wt allele is believed to increase grain protein concentration and has attracted interest from breeders since it could contribute to higher grain quality and more nitrogen-efficient varieties. This study investigated whether Swedish varieties with the wt allele differ from varieties with one of the more common, non-functional alleles in order to examine the effect of the gene in a wide genetic background, and possibly explain why the allele has been retained in Swedish varieties. Forty varieties of spring wheat differing in NAM-B1 allele type were cultivated under controlled conditions. Senescence was monitored and grains were harvested and analyzed for mineral nutrient concentration. Varieties with the wt allele reached anthesis earlier and completed senescence faster than varieties with the non-functional allele. The wt varieties also had more ears, lighter grains and higher yields of P and K. Contrary to previous information on effects of the wt allele, our wt varieties did not have increased grain N concentration or grain N yield. In addition, temporal studies showed that straw length has decreased but grain N yield has remained unaffected over a century of Swedish spring wheat breeding. The faster development of wt varieties supports the hypothesis of NAM-B1 being preserved in Fennoscandia, with its short growing season, because of accelerated development conferred by the NAM-B1 wt allele. Although the possible effects of other gene actions were impossible to distinguish, the genetic resource of Fennoscandian spring wheats with the wt NAM-B1 allele is interesting to investigate further for breeding purposes. PMID:23555754

  17. The association of estimated salt intake with blood pressure in a Viet Nam national survey.

    PubMed

    Jensen, Paul N; Bao, Tran Quoc; Huong, Tran Thi Thanh; Heckbert, Susan R; Fitzpatrick, Annette L; LoGerfo, James P; Ngoc, Truong Le Van; Mokdad, Ali H

    2018-01-01

    To evaluate the association of salt consumption with blood pressure in Viet Nam, a developing country with a high level of salt consumption. Analysis of a nationally representative sample of Vietnamese adults 25-65 years of age who were surveyed using the World Health Organization STEPwise approach to Surveillance protocol. Participants who reported acute illness, pregnancy, or current use of antihypertensive medications were excluded. Daily salt consumption was estimated from fasting mid-morning spot urine samples. Associations of salt consumption with systolic blood pressure and prevalent hypertension were assessed using adjusted linear and generalized linear models. Interaction terms were tested to assess differences by age, smoking, alcohol consumption, and rural/urban status. The analysis included 2,333 participants (mean age: 37 years, 46% male, 33% urban). The average estimated salt consumption was 10g/day. No associations of salt consumption with blood pressure or prevalent hypertension were observed at a national scale in men or women. The associations did not differ in subgroups defined by age, smoking, or alcohol consumption; however, associations differed between urban and rural participants (p-value for interaction of urban/rural status with salt consumption, p = 0.02), suggesting that higher salt consumption may be associated with higher systolic blood pressure in urban residents but lower systolic blood pressure in rural residents. Although there was no evidence of an association at a national level, associations of salt consumption with blood pressure differed between urban and rural residents in Viet Nam. The reasons for this differential association are not clear, and given the large rate of rural to urban migration experienced in Viet Nam, this topic warrants further investigation.

  18. 'Never testing for HIV' among men who have sex with men in Viet Nam: results from an Internet-based cross-sectional survey.

    PubMed

    García, Macarena Cecilia; Duong, Quyen Le; Mercer, Licelot Eralte; Meyer, Samantha Beth; Ward, Paul Russell

    2013-12-28

    Men who have sex with men in Viet Nam have been under-studied as a high-risk group for HIV infection, and this population's percentage and determinants of HIV testing have not been comprehensively investigated. A national Internet-based survey of self-reported sexual and health seeking behaviours was conducted between August and October 2011 with 2077 Vietnamese men who had sex with men in the last twelve months to identify the frequency of 'never testing for HIV' among Internet-using MSM living in Viet Nam, as well as the factors associated with this HIV-related high-rish behavior. Logistic regression analyses were conducted to assess the demographic characteristics and behaviours predicting never testing for HIV. A total of 76.5% of men who have sex with men who were surveyed reported never having been voluntarily tested for HIV. Predictors of never being tested included having a monthly income less than VND 5 Million, being a student, using the Internet less than 15 hour per week, and not participating in a behavioural HIV intervention. Never testing for HIV is common among Internet-using men who have sex with men in Viet Nam. Given the dangerously high prevalence of this high-risk behaviour, our findings underscore the urgent need for segmented and targeted HIV prevention, care and treatment strategies, focusing on drastically reducing the number of men who have sex with men never testing for HIV in Viet Nam.

  19. Land use changes assessment using spatial data: Case study in Cong river basin - Thai Nguyen City - Viet Nam

    NASA Astrophysics Data System (ADS)

    Nguyen, Hieu

    Land use changes are being interested in most countries, especially in developing countries. Because land use changes always impacts on sustainable development not only in a region or a country but also in whole the world. Viet Nam is a developing country, in the last 10 years, land uses have rapidly changed in most provinces. Many of agriculture areas, forest areas have changed for various purposes as urban sprawl, establishing new industrial parks, public areas, mining and other land uses relate to human activities or economic function associated with a specific piece of land. Beside efficiencies of economic and society, then environment issues have been threatening serious pollution, are from land use changes. Remote sensing images application on studying land use changes, has been done in many countries around the world, and has brought high efficiencies. However, this application is still very new and limited in Viet Nam due to lacking of materials, tools, experts of remote sensing. This study used spatial data as Landsat TM images, SPOT5 images and land use planning maps to rapidly assess on happenings of land uses in the period 2000 -2010 in Cong river basin (Thai Nguyen City, Viet Nam), and to forecast the changes of land uses in the period 2010 - 2020. The results had a good accuracy and to be important references for authorities, policy makers in local land use.

  20. Diagnosis of the influence of the solar cycle in the annular character of the NAM using RAM.

    NASA Astrophysics Data System (ADS)

    de La Torre, L.; Gimeno, L.; Tesouro, M.; Nieto, R.; Añel, J. A.; Ribera, P.; García, R.; Hernández, E.

    2003-04-01

    It has been suggested that the North Atlantic Oscillation is a regional expression of the so called Northern Hemisphere Annular Mode (NAM), although some evidences have been found against this hypothesis. However, recent studies conect the spatial structure of the NAM with the phase of solar cycle, being annular-like only for the periods of high solar activity. With this work we try to make a contribution to the debate by using atmospheric relative angular momentum (RAM) to diagnose the annular character of the mode. Correlations of RAM vs. temperature and geopotential height at different levels for high activity years show a more zonally extended pattern than those for low activity years. Moreover, the Atlantic pattern is always shown, even when using RAM computed by 60º longitude sectors. On the other hand, the Pacific pattern almost dissapear.

  1. Control of malaria: a successful experience from Viet Nam.

    PubMed Central

    Hung, Le Q.; Vries, Peter J. de; Giao, Phan T.; Nam, Nguyen V.; Binh, Tran Q.; Chong, M. T.; Quoc, N. T. T. A.; Thanh, T. N.; Hung, L. N.; Kager, P. A.

    2002-01-01

    OBJECTIVE: To follow malaria prospectively in an ethnic minority commune in the south of Viet Nam with high malaria transmission and seasonal fluctuation, during malaria control interventions using insecticide-treated bednets (ITBNs) and early diagnosis and treatment (EDT) of symptomatic patients. METHODS: From 1994 onwards the following interventions were used: distribution of ITBNs to all households with biannual reimpregnation; construction of a health post and appointment of staff trained in microscopic diagnosis and treatment of malaria; regular supply of materials and drugs; annual cross-sectional malaria surveys with treatment of all parasitaemic subjects, and a programme of community involvement and health education. Surveys were held yearly at the end of the rainy season. During the surveys, demographic data were updated. Diagnosis and treatment of malaria were free of charge. Plasmodium falciparum infection was treated with artesunate and P. vivax infection with chloroquine plus primaquine. FINDINGS: The baseline survey in 1994 recorded 716 inhabitants. Of the children under 2 years of age, 37% were parasitaemic; 56% of children aged 2-10 years, and 35% of the remaining population were parasitaemic. P. falciparum accounted for 73-79% of these infections. The respective splenomegaly rates for the above-mentioned age groups were 20%, 56%, and 32%. In 1999, the proportion of parasitaemic subjects was 4%, 7% and 1%, respectively, of which P.falciparum contributed 56%. The splenomegaly rate was 0%, 5% and 2%, respectively. CONCLUSIONS: A combination of ITBNs and EDT, provided free of charge, complemented by annual diagnosis and treatment during malaria surveys and community involvement with health education successfully brought malaria under control. This approach could be applied to other regions in the south of Viet Nam and provides a sound basis for further studies in other areas with different epidemiological patterns of malaria. PMID:12219158

  2. Kinetics of OH- and Cl-initiated oxidation of CH2dbnd CHC(O)O(CH2)2CH3 and CH2dbnd CHCH2C(O)O(CH2)2CH3 and fate of the alkoxy radicals formed

    NASA Astrophysics Data System (ADS)

    Rivela, Cynthia; Blanco, María B.; Teruel, Mariano A.

    2016-05-01

    Rate coefficients of the reactions of OH and Cl radicals with vinyl and allyl butyrate were determined for the first time at 298 K and 1 atm using the relative method to be (in cm3 molecule-1 s-1): k1(OH + CH2dbnd CHC(O)O(CH2)2CH3) = (2.61 ± 0.31) × 10-11, k2(Cl + CH2dbnd CHC(O)O(CH2)2CH3) = (2.48 ± 0.89) × 10-10, k3(OH + CH2dbnd CHCH2C(O)O(CH2)2CH3) = (2.89 ± 0.31) × 10-11, and k4(Cl + CH2dbnd CHCH2C(O)O(CH2)2CH3) = (2.25 ± 0.96) × 10-10. Reactivity trends and atmospheric lifetimes of esters are presented. Additionally, a product study shown butyric acid and polifunctional products for the reactions of vinyl and allyl butyrate, respectively and general mechanism is proposed.

  3. ‘Never testing for HIV’ among Men who have Sex with Men in Viet Nam: results from an internet-based cross-sectional survey

    PubMed Central

    2013-01-01

    Background Men who have sex with men in Viet Nam have been under-studied as a high-risk group for HIV infection, and this population’s percentage and determinants of HIV testing have not been comprehensively investigated. Methods A national Internet-based survey of self-reported sexual and health seeking behaviours was conducted between August and October 2011 with 2077 Vietnamese men who had sex with men in the last twelve months to identify the frequency of ‘never testing for HIV’ among Internet-using MSM living in Viet Nam, as well as the factors associated with this HIV-related high-rish behavior. Logistic regression analyses were conducted to assess the demographic characteristics and behaviours predicting never testing for HIV. Results A total of 76.5% of men who have sex with men who were surveyed reported never having been voluntarily tested for HIV. Predictors of never being tested included having a monthly income less than VND 5 Million, being a student, using the Internet less than 15 hour per week, and not participating in a behavioural HIV intervention. Conclusions Never testing for HIV is common among Internet-using men who have sex with men in Viet Nam. Given the dangerously high prevalence of this high-risk behaviour, our findings underscore the urgent need for segmented and targeted HIV prevention, care and treatment strategies, focusing on drastically reducing the number of men who have sex with men never testing for HIV in Viet Nam. PMID:24373483

  4. The association of estimated salt intake with blood pressure in a Viet Nam national survey

    PubMed Central

    Bao, Tran Quoc; Huong, Tran Thi Thanh; Heckbert, Susan R.; Fitzpatrick, Annette L.; LoGerfo, James P.; Ngoc, Truong Le Van; Mokdad, Ali H.

    2018-01-01

    Objective To evaluate the association of salt consumption with blood pressure in Viet Nam, a developing country with a high level of salt consumption. Design and setting Analysis of a nationally representative sample of Vietnamese adults 25–65 years of age who were surveyed using the World Health Organization STEPwise approach to Surveillance protocol. Participants who reported acute illness, pregnancy, or current use of antihypertensive medications were excluded. Daily salt consumption was estimated from fasting mid-morning spot urine samples. Associations of salt consumption with systolic blood pressure and prevalent hypertension were assessed using adjusted linear and generalized linear models. Interaction terms were tested to assess differences by age, smoking, alcohol consumption, and rural/urban status. Results The analysis included 2,333 participants (mean age: 37 years, 46% male, 33% urban). The average estimated salt consumption was 10g/day. No associations of salt consumption with blood pressure or prevalent hypertension were observed at a national scale in men or women. The associations did not differ in subgroups defined by age, smoking, or alcohol consumption; however, associations differed between urban and rural participants (p-value for interaction of urban/rural status with salt consumption, p = 0.02), suggesting that higher salt consumption may be associated with higher systolic blood pressure in urban residents but lower systolic blood pressure in rural residents. Conclusions Although there was no evidence of an association at a national level, associations of salt consumption with blood pressure differed between urban and rural residents in Viet Nam. The reasons for this differential association are not clear, and given the large rate of rural to urban migration experienced in Viet Nam, this topic warrants further investigation. PMID:29346423

  5. Factors associated with breastfeeding intent among mothers of newborn babies in Da Nang, Viet Nam.

    PubMed

    Nguyen, Phuong Thi Kim; Tran, Hoang Thi; Thai, Thuy Thi Thanh; Foster, Kirsty; Roberts, Christine L; Marais, Ben J

    2018-01-01

    Breastfeeding is recognized as the single most cost-effective intervention to reduce child morbidity and mortality. However, few studies have explored perceived barriers to breastfeeding and factors associated with breastfeeding intent among mothers of newborn babies in Viet Nam. We conducted a study to assess breastfeeding initiation rates, intent to breastfeed exclusively for 6 months or more and perceived barriers to breastfeed among mothers of newborn babies in Da Nang, Viet Nam. We conducted a cross-sectional questionnaire survey of mothers in the postnatal wards of Da Nang Hospital for Women and Children in central Viet Nam from 10 February 2017 to 24 February 2017, following implementation of the World Health Organization (WHO) Essential Newborn Care (ENC) package. Of 286 mothers surveyed, 259 (90.6%) initiated breastfeeding; 203/258 (78.7%) within 1 hour (h) of birth. Most (207, 72.4%) mothers indicated intent to breastfeed exclusively for 6 months or more, but this was lower among mothers of preterm babies (82.2% versus 20.0%, p  < 0.001) and those without post-secondary school education (74.8% versus 55.6%, p  = 0.02). Amongst mothers struggling to establish breastfeeding, 18/27 (66.7%) had a Cesarean section. Planned non-exclusive breastfeeding was mostly (39, 60.9%) motivated by mothers' concern that their milk supply would be insufficient for their baby's growth requirements. Most mothers had good knowledge about the benefits of breastfeeding and indicated strong decision autonomy. We documented high rates of early breastfeeding establishment and intent to breastfeed exclusively for 6 months or more. This probably reflects high levels of maternal education and successful implementation of the WHO ENC package. Mothers of premature babies may benefit from additional support.

  6. Detection of potentially novel paramyxovirus and coronavirus viral RNA in bats and rats in the Mekong Delta region of southern Viet Nam.

    PubMed

    Berto, A; Anh, P H; Carrique-Mas, J J; Simmonds, P; Van Cuong, N; Tue, N T; Van Dung, N; Woolhouse, M E; Smith, I; Marsh, G A; Bryant, J E; Thwaites, G E; Baker, S; Rabaa, M A

    2018-02-01

    Bats and rodents are being increasingly recognized as reservoirs of emerging zoonotic viruses. Various studies have investigated bat viruses in tropical regions, but to date there are no data regarding viruses with zoonotic potential that circulate in bat and rat populations in Viet Nam. To address this paucity of data, we sampled three bat farms and three wet markets trading in rat meat in the Mekong Delta region of southern Viet Nam. Faecal and urine samples were screened for the presence of RNA from paramyxoviruses, coronaviruses and filoviruses. Paramyxovirus RNA was detected in 4 of 248 (1%) and 11 of 222 (4.9%) bat faecal and urine samples, respectively. Coronavirus RNA was detected in 55 of 248 (22%) of bat faecal samples; filovirus RNA was not detected in any of the bat samples. Further, coronavirus RNA was detected in 12 of 270 (4.4%) of rat faecal samples; all samples tested negative for paramyxovirus. Phylogenetic analysis revealed that the bat paramyxoviruses and bat and rat coronaviruses were related to viruses circulating in bat and rodent populations globally, but showed no cross-species mixing of viruses between bat and rat populations within Viet Nam. Our study shows that potentially novel variants of paramyxoviruses and coronaviruses commonly circulate in bat and rat populations in Viet Nam. Further characterization of the viruses and additional human and animal surveillance is required to evaluate the likelihood of viral spillover and to assess whether these viruses pose a risk to human health. © 2017 The Authors. Zoonoses and Public Health Published by Blackwell Verlag GmbH.

  7. Unimolecular reactivity of organotrifluoroborate anions, RBF3- , and their alkali metal cluster ions, M(RBF3 )2- (M = Na, K; R = CH3 , CH3 CH2 , CH3 (CH2 )3 , CH3 (CH2 )5 , c-C3 H5 , C6 H5 , C6 H5 CH2 , CH2 CHCH2 , CH2 CH, C6 H5 CO).

    PubMed

    Bathie, Fiona L B; Bowen, Chris J; Hutton, Craig A; O'Hair, Richard A J

    2018-07-15

    Potassium organotrifluoroborates (RBF 3 K) are important reagents used in organic synthesis. Although mass spectrometry is commonly used to confirm their molecular formulae, the gas-phase fragmentation reactions of organotrifluoroborates and their alkali metal cluster ions have not been previously reported. Negative-ion mode electrospray ionization (ESI) together with collision-induced dissociation (CID) using a triple quadrupole mass spectrometer were used to examine the fragmentation pathways for RBF 3 - (where R = CH 3 , CH 3 CH 2 , CH 3 (CH 2 ) 3 , CH 3 (CH 2 ) 5 , c-C 3 H 5 , C 6 H 5 , C 6 H 5 CH 2 , CH 2 CHCH 2 , CH 2 CH, C 6 H 5 CO) and M(RBF 3 ) 2 - (M = Na, K), while density functional theory (DFT) calculations at the M06/def2-TZVP level were used to examine the structures and energies associated with fragmentation reactions for R = Me and Ph. Upon CID, preferentially elimination of HF occurs for RBF 3 - ions for systems where R = an alkyl anion, whereas R - formation is favoured when R = a stabilized anion. At higher collision energies loss of F - and additional HF losses are sometimes observed. Upon CID of M(RBF 3 ) 2 - , formation of RBF 3 - is the preferred pathway with some fluoride transfer observed only when M = Na. The DFT-calculated relative thermochemistry for competing fragmentation pathways is consistent with the experiments. The main fragmentation pathways of RBF 3 - are HF elimination and/or R - loss. This contrasts with the fragmentation reactions of other organometallate anions, where reductive elimination, beta hydride transfer and bond homolysis are often observed. The presence of fluoride transfer upon CID of Na(RBF 3 ) 2 - but not K(RBF 3 ) 2 - is in agreement with the known fluoride affinities of Na + and K + and can be rationalized by Pearson's HSAB theory. Copyright © 2018 John Wiley & Sons, Ltd.

  8. Identification of QTL conferring resistance to stripe rust (Puccinia striiformis f. sp. hordei) and leaf rust (Puccinia hordei) in barley using nested association mapping (NAM).

    PubMed

    Vatter, Thomas; Maurer, Andreas; Perovic, Dragan; Kopahnke, Doris; Pillen, Klaus; Ordon, Frank

    2018-01-01

    The biotrophic rust fungi Puccinia hordei and Puccinia striiformis are important barley pathogens with the potential to cause high yield losses through an epidemic spread. The identification of QTL conferring resistance to these pathogens is the basis for targeted breeding approaches aiming to improve stripe rust and leaf rust resistance of modern cultivars. Exploiting the allelic richness of wild barley accessions proved to be a valuable tool to broaden the genetic base of resistance of barley cultivars. In this study, SNP-based nested association mapping (NAM) was performed to map stripe rust and leaf rust resistance QTL in the barley NAM population HEB-25, comprising 1,420 lines derived from BC1S3 generation. By scoring the percentage of infected leaf area, followed by calculation of the area under the disease progress curve and the average ordinate during a two-year field trial, a large variability of resistance across and within HEB-25 families was observed. NAM based on 5,715 informative SNPs resulted in the identification of twelve and eleven robust QTL for resistance against stripe rust and leaf rust, respectively. Out of these, eight QTL for stripe rust and two QTL for leaf rust are considered novel showing no overlap with previously reported resistance QTL. Overall, resistance to both pathogens in HEB-25 is most likely due to the accumulation of numerous small effect loci. In addition, the NAM results indicate that the 25 wild donor QTL alleles present in HEB-25 strongly differ in regard to their individual effect on rust resistance. In future, the NAM concept will allow to select and combine individual wild barley alleles from different HEB parents to increase rust resistance in barley. The HEB-25 results will support to unravel the genetic basis of rust resistance in barley, and to improve resistance against stripe rust and leaf rust of modern barley cultivars.

  9. Seasonal variability of faecal indicator bacteria numbers and die-off rates in the Red River basin, North Viet Nam

    NASA Astrophysics Data System (ADS)

    Nguyen, Huong Thi Mai; Le, Quynh Thi Phuong; Garnier, J.; Janeau, J.-L.; Rochelle-Newall, E.

    2016-02-01

    The Red River is the second largest river in Viet Nam and constitutes the main water source for a large percentage of the population of North Viet Nam. Here we present the results of an annual survey of Escherichia coli (EC) and Total Coliforms (TC) in the Red River basin, North Viet Nam. The objective of this work was to obtain information on faecal indicator bacteria (FIB) numbers over an annual cycle and, secondly, to determine the die-off rates of these bacterial indicators. Monthly observations at 10 stations from July 2013-June 2014 showed that TC and EC reached as high as 39100 cfu (colony forming units) 100 ml-1 and 15300 colonies 100 ml-1, respectively. We observed a significant seasonal difference for TC (p < 0.05) with numbers being higher during the wet season. In contrast, no significant seasonal difference was found for EC. The FIB die-off rates ranged from 0.01 d-1 to a maximum of 1.13 d-1 for EC and from 0.17 d-1 to 1.33 d-1 for TC. Die-off rates were significantly higher for free bacteria than for total (free + particle attached) bacteria, suggesting that particle attachment provided a certain level of protection to FIB in this system.

  10. Seasonal variability of faecal indicator bacteria numbers and die-off rates in the Red River basin, North Viet Nam.

    PubMed

    Nguyen, Huong Thi Mai; Le, Quynh Thi Phuong; Garnier, J; Janeau, J-L; Rochelle-Newall, E

    2016-02-12

    The Red River is the second largest river in Viet Nam and constitutes the main water source for a large percentage of the population of North Viet Nam. Here we present the results of an annual survey of Escherichia coli (EC) and Total Coliforms (TC) in the Red River basin, North Viet Nam. The objective of this work was to obtain information on faecal indicator bacteria (FIB) numbers over an annual cycle and, secondly, to determine the die-off rates of these bacterial indicators. Monthly observations at 10 stations from July 2013-June 2014 showed that TC and EC reached as high as 39100 cfu (colony forming units) 100 ml(-1) and 15300 colonies 100 ml(-1), respectively. We observed a significant seasonal difference for TC (p < 0.05) with numbers being higher during the wet season. In contrast, no significant seasonal difference was found for EC. The FIB die-off rates ranged from 0.01 d(-1) to a maximum of 1.13 d(-1) for EC and from 0.17 d(-1) to 1.33 d(-1) for TC. Die-off rates were significantly higher for free bacteria than for total (free + particle attached) bacteria, suggesting that particle attachment provided a certain level of protection to FIB in this system.

  11. ChIP-seq.

    PubMed

    Kim, Tae Hoon; Dekker, Job

    2018-05-01

    Owing to its digital nature, ChIP-seq has become the standard method for genome-wide ChIP analysis. Using next-generation sequencing platforms (notably the Illumina Genome Analyzer), millions of short sequence reads can be obtained. The densities of recovered ChIP sequence reads along the genome are used to determine the binding sites of the protein. Although a relatively small amount of ChIP DNA is required for ChIP-seq, the current sequencing platforms still require amplification of the ChIP DNA by ligation-mediated PCR (LM-PCR). This protocol, which involves linker ligation followed by size selection, is the standard ChIP-seq protocol using an Illumina Genome Analyzer. The size-selected ChIP DNA is amplified by LM-PCR and size-selected for the second time. The purified ChIP DNA is then loaded into the Genome Analyzer. The ChIP DNA can also be processed in parallel for ChIP-chip results. © 2018 Cold Spring Harbor Laboratory Press.

  12. ChIP and ChIP-Related Techniques: Expanding the Fields of Application and Improving ChIP Performance.

    PubMed

    Visa, Neus; Jordán-Pla, Antonio

    2018-01-01

    Protein-DNA interactions in vivo can be detected and quantified by chromatin immunoprecipitation (ChIP). ChIP has been instrumental for the advancement of epigenetics and has set the groundwork for the development of a number of ChIP-related techniques that have provided valuable information about the organization and function of genomes. Here, we provide an introduction to ChIP and discuss the applications of ChIP in different research areas. We also review some of the strategies that have been devised to improve ChIP performance.

  13. Dioxin reservoirs in southern Viet Nam--a legacy of Agent Orange.

    PubMed

    Dwernychuk, L Wayne; Cau, Hoang Dinh; Hatfield, Christopher T; Boivin, Thomas G; Hung, Tran Manh; Dung, Phung Tri; Thai, Nguyen Dinh

    2002-04-01

    In the isolated Aluoi Valley of central Viet Nam, very high levels of 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) were measured in soil, fish fat, duck fat, pooled human blood and breast milk samples collected from A So village between 1996 and 1999. The village was situated on a former military base occupied by US Special Forces between 1963 and 1966. TCDD was a contaminant of the herbicide "Agent Orange", aerially sprayed in the valley between 1965 and 1970, and stored at the A So base. Measured levels were lower near the sites of two other former US bases in the valley which had been occupied for shorter periods of time. In areas where Agent Orange had been applied by low-flying aircraft, levels of TCDD in soil, food and human samples were elevated, but lower than those near the three former US bases. We confirm the apparent food chain transfer of TCDD from contaminated soil to cultured fish pond sediments to fish and duck tissues, then to humans as measured in whole blood and breast milk. We theorize that the Aluoi Valley is a microcosm of southern Viet Nam, where numerous reservoirs of TCDD exist in the soil of former military installations south of the former demilitarized zone. Large quantities of Agent Orange were stored at many sites, used in ground and aerial applications, and spilled. TCDD, through various forms of soil disturbance, can be mobilized from these reservoirs after decades below the surface, and subsequently, introduced into the human food chain.

  14. ChIPpeakAnno: a Bioconductor package to annotate ChIP-seq and ChIP-chip data

    PubMed Central

    2010-01-01

    Background Chromatin immunoprecipitation (ChIP) followed by high-throughput sequencing (ChIP-seq) or ChIP followed by genome tiling array analysis (ChIP-chip) have become standard technologies for genome-wide identification of DNA-binding protein target sites. A number of algorithms have been developed in parallel that allow identification of binding sites from ChIP-seq or ChIP-chip datasets and subsequent visualization in the University of California Santa Cruz (UCSC) Genome Browser as custom annotation tracks. However, summarizing these tracks can be a daunting task, particularly if there are a large number of binding sites or the binding sites are distributed widely across the genome. Results We have developed ChIPpeakAnno as a Bioconductor package within the statistical programming environment R to facilitate batch annotation of enriched peaks identified from ChIP-seq, ChIP-chip, cap analysis of gene expression (CAGE) or any experiments resulting in a large number of enriched genomic regions. The binding sites annotated with ChIPpeakAnno can be viewed easily as a table, a pie chart or plotted in histogram form, i.e., the distribution of distances to the nearest genes for each set of peaks. In addition, we have implemented functionalities for determining the significance of overlap between replicates or binding sites among transcription factors within a complex, and for drawing Venn diagrams to visualize the extent of the overlap between replicates. Furthermore, the package includes functionalities to retrieve sequences flanking putative binding sites for PCR amplification, cloning, or motif discovery, and to identify Gene Ontology (GO) terms associated with adjacent genes. Conclusions ChIPpeakAnno enables batch annotation of the binding sites identified from ChIP-seq, ChIP-chip, CAGE or any technology that results in a large number of enriched genomic regions within the statistical programming environment R. Allowing users to pass their own annotation data such

  15. Selenium carboxylic acids betaine; 3,3‧,3″-selenotris(propanoic acid) betaine, Se(CH2CH2COOH)2(CH2CH2COO)

    NASA Astrophysics Data System (ADS)

    Doudin, Khalid; Törnroos, Karl W.

    2017-06-01

    Attempts to prepare [Se(CH2CH2COOH)3]+Cl- from Se(CH2CH2COOH)2 and H2Cdbnd CHCOOH in concentrated hydrochloric acid, for the corresponding sulfonium salt, led exclusively to the Se-betaine, Se(CH2CH2COOH)2(CH2CH2COO). The Se-betaine crystallises in the space group P2l/c with the cell dimensions at 223 K, a = 5.5717(1), b = 24.6358(4), c = 8.4361(1) Å, β = 104.762(1)°, V = 1119.74(3) Å3, Z = 4, Dcalc = 1.763 Mgm- 3, μ = 3.364 Mm-1. The structure refined to RI = 0.0223 for 2801 reflections with Fo > 4σ(Fo). In the crystalline state the molecule is intermolecularly linked to neighbouring molecules by a number of hydrogen bonds; a very strong carboxylic-carboxylate bond with an O⋯O distance of 2.4435(16) Å, a medium strong carboxylic-carboxylate bond with an O⋯O distance of 2.6431(16) Å and several weak O⋯H(CH2) with O⋯C distances between 3.2 and 3.3 Å. In the carboxylic group involved in the very strong hydrogen bond the O⋯H bond is antiperiplanar to the Cdbnd O bond while the Osbnd H bond is periplanar to the Cdbnd O bond in the second carboxylic group. Based upon the Csbnd O bond lengths and the elongation of the Osbnd H bond involved in the strong hydrogen bond one may describe the compound as strongly linked units of Se(CH2CH2COOH)(CH2CH2COO)2 rather than Se(CH2CH2COOH)2(CH2CH2COO). The selenium atom forms two strong intramolecular 1,5-Se⋯O contacts, with a carboxylate oxygen atom, 2.9385(12) Å, and with a carboxylic oxygen atom, 2.8979(11) Å. To allow for these contacts the two organic fragments have been forced into the periplanar conformation. The molecule is only slightly asymmetric with regard to the Csbnd Sesbnd C bond angles but is very asymmetric with regard to the torsion angles.

  16. Drinking & driving in Viet Nam: prevalence, knowledge, attitudes, and practices in two provinces.

    PubMed

    Bachani, Abdulgafoor M; Jessani, Nasreen S; Pham, V Cuong; Quang, La Ngoc; Nguyen, Phuong N; Passmore, Jonathon; Hyder, Adnan A

    2013-12-01

    Viet Nam is experiencing a shift in its burden of disease profile with injuries becoming more prominent. A history of high alcohol involvement in road traffic crashes despite stringent laws led to increased enforcement by police, enhanced public education messaging and targeted social marketing campaigns in Ha Nam and Ninh Binh provinces in Viet Nam. This study aims to illustrate the changes in prevalence (November 2010 to December 2011) and knowledge, attitudes and practices (KAP) around alcohol use and drink-driving for the year 2011. Breath Alcohol Concentration (BrAC) was collected through police enforcement checkpoints in the two provinces. The proportion of drivers with BrAC above the legal limit was plotted over time for both provinces. The trend in prevalence of drink-driving over time was further assessed using Poisson regression models. Prevailing KAPs were determined through surveying randomly selected road users over the age of 17 years at gas stations at quarterly intervals. Cross tabulations of key variables as well Chi-Square statistic were used to assess associations. A total of 8,404 drivers were tested for BrAC levels of which less than 0.25% were female. Of 1,639 drivers displaying BrAC levels in excess of the legal limit, 87.3% were car drivers, 7.9% motorcyclists and 86% were between the ages of 25 and 44 years. KAP surveys captured 1,661 drivers over the study period. The prevalence of self-reported drink-driving increased 6 percentage points among respondents aged 27-36. Between 44% (January 2011) and 49% (December 2011) of respondents indicated awareness of a drinking and driving Blood Alcohol Concentration (BAC) or BrAC limit and only 25% of all study participants recalled being penalized for a traffic violation - none of which were for drink-driving. While there has been some reduction in drink-driving prevalence, inadequate or incorrect knowledge on drink-driving legislation appears to be an impediment to greater gains. Increased

  17. The World Report on Disability in relation to the development of speech-language pathology in Viet Nam.

    PubMed

    Atherton, Marie; Dung, Nguyễn Thị Ngọc; Nhân, Võ Hoàng

    2013-02-01

    Wylie, McAllister, Davidson, and Marshall (2013) argue that recommendations made within the World Report on Disability provide an opportunity for speech-language pathologists to consider new ways of developing services for people with communication and swallowing disorders. They propose that current approaches to the delivery of speech-language pathology services are largely embedded within the medical model of impairment, thereby limiting the ability of services to meet the needs of people in a holistic manner. In this paper, the criticality of selecting an appropriate service delivery model is discussed within the context of a recently established post-graduate speech therapy education programme in Viet Nam. Driving forces for the implementation of the program will be explored, as will the factors that determined the choice of service delivery. Opportunities and challenges to the long-term viability of the program and the program's potential to meet the needs of persons with communication and swallowing disorders in Viet Nam will be considered.

  18. Multiple and concurrent sexual partnerships among men who have sex with men in Viet Nam: results from a National Internet-based Cross-sectional Survey.

    PubMed

    García, M C; Duong, Q L; Meyer, S B; Ward, P R

    2016-03-01

    Men who have sex with men (MSM) are one of the largest HIV risk groups in Viet Nam and have been understudied. Sexual concurrency and multiple sex partnerships may contribute to high HIV incidence among MSM in Viet Nam. Limited information is available on concurrency and multiple sexual partnerships among MSM in Viet Nam or on the extent to which this population engages in concurrent and multiple unprotected anal intercourse. Data are from a self-administered Internet-based survey of Vietnamese MSM aged 18 years or older, having sex with male partner(s) in the last 12 months and recruited from social networking MSM-specific websites in Viet Nam. Multiple partnerships and concurrency were measured using the UNAIDS-recommended sexual partner matrix, a key component in the questionnaire. Concurrent and multiple sexual partnerships were analyzed at the individual level. Logistic regression analyses were conducted to assess the demographic characteristics and behaviors associated with multiple sexual partnerships. A total of 1695 MSM reported on multiple sexual partnerships; 69.5% indicated multiple sexual partnerships in the last 6 months. A total of 257 MSM reported on concurrent sexual partnerships, with 51.0% reporting penetrative sex with concurrent partners in the last 6 months. Respondents were more likely to engage in multiple sexual partnerships if they were no longer a student, consumed alcohol before and/or during sex, used the Internet to meet casual sex partners and had never participated in a behavioral HIV intervention. Multiple sexual partnerships in the previous 6 months were common among MSM surveyed, as was sexual concurrency. High levels of multiple and concurrent sexual partnerships may be catalyzing the transmission of HIV among MSM in Viet Nam. Given the high prevalence of this high-risk sexual behavior, our findings underscore the urgent need for targeted prevention efforts, focusing on the reduction of multiple and concurrent sexual partners

  19. Laboratory Spectroscopy of CH(+) and Isotopic CH

    NASA Technical Reports Server (NTRS)

    Pearson, John C.; Drouin, Brian J.

    2006-01-01

    The A1II - X1(Epsilon) electronic band of the CH(+) ion has been used as a probe of the physical and dynamical conditions of the ISM for 65 years. In spite of being one of the first molecular species observed in the ISM and the very large number of subsequent observations with large derived column densities, the pure rotational spectra of CH+ has remained elusive in both the laboratory and in the ISM as well. We report the first laboratory measurement of the pure rotation of the CH(+) ion and discuss the detection of CH-13(+) in the ISM. Also reported are the somewhat unexpected chemical conditions that resulted in laboratory production.

  20. libChEBI: an API for accessing the ChEBI database.

    PubMed

    Swainston, Neil; Hastings, Janna; Dekker, Adriano; Muthukrishnan, Venkatesh; May, John; Steinbeck, Christoph; Mendes, Pedro

    2016-01-01

    ChEBI is a database and ontology of chemical entities of biological interest. It is widely used as a source of identifiers to facilitate unambiguous reference to chemical entities within biological models, databases, ontologies and literature. ChEBI contains a wealth of chemical data, covering over 46,500 distinct chemical entities, and related data such as chemical formula, charge, molecular mass, structure, synonyms and links to external databases. Furthermore, ChEBI is an ontology, and thus provides meaningful links between chemical entities. Unlike many other resources, ChEBI is fully human-curated, providing a reliable, non-redundant collection of chemical entities and related data. While ChEBI is supported by a web service for programmatic access and a number of download files, it does not have an API library to facilitate the use of ChEBI and its data in cheminformatics software. To provide this missing functionality, libChEBI, a comprehensive API library for accessing ChEBI data, is introduced. libChEBI is available in Java, Python and MATLAB versions from http://github.com/libChEBI, and provides full programmatic access to all data held within the ChEBI database through a simple and documented API. libChEBI is reliant upon the (automated) download and regular update of flat files that are held locally. As such, libChEBI can be embedded in both on- and off-line software applications. libChEBI allows better support of ChEBI and its data in the development of new cheminformatics software. Covering three key programming languages, it allows for the entirety of the ChEBI database to be accessed easily and quickly through a simple API. All code is open access and freely available.

  1. Maternal health care utilization in Viet Nam: increasing ethnic inequity

    PubMed Central

    Lincetto, Ornella; Du, Nguyen Huy; Burgess, Craig; Hoa, Dinh Thi Phuong

    2013-01-01

    Abstract Objective To investigate changes that took place between 2006 and 2010 in the inequity gap for antenatal care attendance and delivery at health facilities among women in Viet Nam. Methods Demographic, socioeconomic and obstetric data for women aged 15–49 years were extracted from Viet Nam’s Multiple Indicator Cluster Survey for 2006 (MICS3) and 2010–2011 (MICS4). Multivariate logistic regression was performed to determine if antenatal care attendance and place of delivery were significantly associated with maternal education, maternal ethnicity (Kinh/Hoa versus other), household wealth and place of residence (urban versus rural). These independent variables correspond to the analytical framework of the Commission on Social Determinants of Health. Findings Large discrepancies between urban and rural populations were found in both MICS3 and MICS4. Although antenatal care attendance and health facility delivery rates improved substantially between surveys (from 86.3 to 92.1% and from 76.2 to 89.7%, respectively), inequities increased, especially along ethnic lines. The risk of not giving birth in a health facility increased significantly among ethnic minority women living in rural areas. In 2006 this risk was nearly five times higher than among women of Kinh/Hoa (majority) ethnicity (odds ratio, OR: 4.67; 95% confidence interval, CI: 2.94–7.43); in 2010–2011 it had become nearly 20 times higher (OR: 18.8; 95% CI: 8.96–39.2). Conclusion Inequity in maternal health care utilization has increased progressively in Viet Nam, primarily along ethnic lines, and vulnerable groups in the country are at risk of being left behind. Health-care decision-makers should target these groups through affirmative action and culturally sensitive interventions. PMID:23599548

  2. Impact of Adverse Events Following Immunization in Viet Nam in 2013 on chronic hepatitis B infection.

    PubMed

    Li, Xi; Wiesen, Eric; Diorditsa, Sergey; Toda, Kohei; Duong, Thi Hong; Nguyen, Lien Huong; Nguyen, Van Cuong; Nguyen, Tran Hien

    2016-02-03

    Adverse Events Following Immunization in Viet Nam in 2013 led to substantial reductions in hepatitis B vaccination coverage (both the birth dose and the three-dose series). In order to estimate the impact of the reduction in vaccination coverage on hepatitis B transmission and future mortality, a widely-used mathematical model was applied to the data from Viet Nam. Using the model, we estimated the number of chronic infections and deaths that are expected to occur in the birth cohort in 2013 and the number of excessive infections and deaths attributable to the drop in immunization coverage in 2013. An excess of 90,137 chronic infections and 17,456 future deaths were estimated to occur in the 2013 birth cohort due to the drop in vaccination coverage. This analysis highlights the importance of maintaining high vaccination coverage and swiftly responding to reported Adverse Events Following Immunization in order to regain consumer confidence in the hepatitis B vaccine. Copyright © 2015 World Health Organization; licensee Elsevier. Published by Elsevier Ltd.. All rights reserved.

  3. Seroprevalence survey of avian influenza A(H5N1) among live poultry market workers in northern Viet Nam, 2011.

    PubMed

    Dung, Tham Chi; Dinh, Pham Ngoc; Nam, Vu Sinh; Tan, Luong Minh; Hang, Nguyen Le Khanh; Thanh, Le Thi; Mai, Le Quynh

    2014-01-01

    Highly pathogenic avian influenza A(H5N1) is endemic in poultry in Viet Nam. The country has experienced the third highest number of human infections with influenza A(H5N1) in the world. A study in Hanoi in 2001, before the epizootic that was identified in 2003, found influenza A(H5N1) specific antibodies in 4% of poultry market workers (PMWs). We conducted a seroprevalence survey to determine the seroprevalence of antibodies to influenza A(H5N1) among PMWs in Hanoi, Thaibinh and Thanhhoa provinces. We selected PMWs from five markets, interviewed them and collected blood samples. These were then tested using a horse haemagglutination inhibition assay and a microneutralization assay with all three clades of influenza A(H5N1) viruses that have circulated in Viet Nam since 2004. The overall seroprevalence was 6.1% (95% confidence interval: 4.6-8.3). The highest proportion (7.2%) was found in PMWs in Hanoi, and the majority of seropositive subjects (70.3%) were slaughterers or sellers of poultry. The continued circulation and evolution of influenza A(H5N1) requires comprehensive surveillance of both human and animal sites throughout the country with follow-up studies on PMWs to estimate the risk of avian-human transmission of influenza A(H5N1) in Viet Nam.

  4. Geometric and electronic structures of silicon-sodium binary clusters. I. Ionization energy of SinNam

    NASA Astrophysics Data System (ADS)

    Kishi, Reiko; Iwata, Suehiro; Nakajima, Atsushi; Kaya, Koji

    1997-08-01

    Sodium doped silicon clusters (SinNam; 1⩽n⩽14, 1⩽m⩽5) produced by two types of laser vaporization were studied. The adsorption of Na atoms on the Sin clusters leads the substantial lowering of the ionization energy, Ei, of SinNam clusters. Their reactivity toward NO molecules was measured with a fast flow reactor, and the anticorrelation between the Eis and the reactivity was clearly observed; species having low Ei exhibit high reactivity and vice versa. Moreover, the clear parallelism between the Eis of SinNa and the EAs of Sin is found. This is consistent with the fact that the structure of SinNa clusters keeps the frame of the corresponding Sin cluster unchanged and that the electronic structure of SinNa is similar to that of the corresponding negative ion Sin-. In addition to the experimental studies, the geometries, adsorption energies, and vertical ionization energies of SinNa (n=1-7) were investigated with ab initio MO calculations including electron correlation; The Møller-Plesset perturbation theory was used and the configuration interaction (CI) calculation was carried out, particularly for a diatomic molecule, SiNa.

  5. Determining aspects of ethnicity amongst persons of South Asian origin: the use of a surname-classification programme (Nam Pehchan).

    PubMed

    Macfarlane, Gary J; Lunt, Mark; Palmer, Benedict; Afzal, Cara; Silman, Alan J; Esmail, Aneez

    2007-03-01

    Name-based classification systems are potentially useful in identifying study samples based on probable ethnic minority group. The aim of the current study was to assess the validity of the Nam Pehchan name classification programme of religion and language against subject self-report. A population-based cross-sectional survey conducted in areas of the North-West and West Midland regions of England with a relatively high density of South Asian ethnic minority groups. The sampling frame was age-sex registers of selected general practices and subjects were classified according to language and religion using the Nam Pehchan programme. These were compared with responses by subjects on a self-complete postal questionnaire. One thousand nine hundred and forty-nine subjects who participated, classified themselves as South Asian. Sensitivity in identifying religion was high amongst Muslims (92%) and Sikhs (86%), and somewhat lower in Hindus (62%). Specificity exceeded 95% for all ethnic groups. The vast majority of subjects assigned Punjabi or Gujarati as their main South Asian language indicated that they did in fact speak these languages (97% and 94%, respectively). Subjects assigned Urdu or Bengali, however, were less likely to do so (61% and 35%, respectively). The name-based classification system Nam Pehchan has demonstrated high levels of accuracy in some sub-groups of the South Asian population in determining subjects likely language spoken and religion-and is likely to be a useful additional tool when information on ethnicity is not already available.

  6. Second trimester abortion in Viet Nam: changing to recommended methods and improving service delivery.

    PubMed

    Tuyet, Hoang T D; Thuy, Phan; Trang, Huynh N K

    2008-05-01

    In Viet Nam, abortion has been legal up to 22 weeks of pregnancy since the 1960s. There are about one million induced abortions every year. First trimester abortion is provided at central, provincial, district and commune level, while second trimester abortion is provided only at central and provincial level. For second trimester abortion, dilatation and evacuation (D&E) has been introduced at some central and provincial hospitals, and medical abortion protocols have been included in the draft National Standards and Guidelines currently being updated. However, Kovac's, an unsafe method, is still often used at many provincial hospitals. While access to first trimester abortion services is not difficult, there are still many barriers to second trimester abortion, especially for young, unmarried women. In order to prevent unwanted pregnancies, increase access to safe abortion and improve quality of care, the Vietnamese Ministry of Health is working with others to establish national policies and developing effective models for women-friendly comprehensive abortion care, including post-abortion family planning. This paper, based on published information, interviews and observations by the second author of service delivery in 2006-2008, provides an overview of second trimester abortion services in Viet Nam and ongoing plans for improving them.

  7. Management and treatment outcomes of patients enrolled in MDR-TB treatment in Viet Nam.

    PubMed

    Phuong, N T M; Nhung, N V; Hoa, N B; Thuy, H T; Takarinda, K C; Tayler-Smith, K; Harries, A D

    2016-03-21

    The programmatic management of drug-resistant tuberculosis (TB) in Viet Nam has been rapidly scaled up since 2009. To document the annual numbers of patients enrolled for multidrug-resistant tuberculosis (MDR-TB) treatment during 2010-2014 and to determine characteristics and treatment outcomes of patients initiating treatment during 2010-2012. A retrospective cohort study using national reports and data from the national electronic data system for drug-resistant TB. The number of patients enrolled annually for MDR-TB treatment increased from 97 in 2010 to 1522 in 2014. The majority of patients were middle-aged men who had pulmonary disease and had failed a retreatment regimen; 77% had received ⩾2 courses of TB treatment. Favourable outcomes (cured and treatment completed) were attained in 73% of patients. Unfavourable outcomes included loss to follow-up (12.5%), death (8%) and failure (6.3%). Having had ⩾2 previous treatment courses and being human immunodeficiency virus-positive were associated with unfavourable outcomes. Increasing numbers of patients are being treated for MDR-TB each year with good treatment outcomes under national programme management in Viet Nam. However, there is a need to increase case detection-currently at 30% of the estimated 5100 MDR-TB cases per year, reduce adverse outcomes and improve monitoring and evaluation.

  8. Collaborative activities and treatment outcomes in patients with HIV-associated tuberculosis in Viet Nam.

    PubMed

    Huyen, T T T; Nhung, N V; Shewade, H D; Hoa, N B; Harries, A D

    2016-03-21

    The National Tuberculosis (TB) Programme in Viet Nam and Ho Chi Minh City (HCMC). To determine 1) at national level between 2011 and 2013, the relationship between human immunodeficiency virus (HIV) testing, uptake of TB-HIV interventions and adverse treatment outcomes among TB-HIV patients; and 2) in HCMC in 2013, patient characteristics associated with adverse outcomes. An ecological study reviewing aggregate nationwide data and a retrospective cohort review in HCMC. Nationwide, from 2011 to 2013, HIV testing increased in TB patients from 58% to 68% and antiretroviral therapy (ART) increased in TB-HIV patients from 54% to 63%. Adverse treatment outcomes in TB-HIV patients increased from 24% to 27%, largely due to transfer out (5-9% increase) and death. The Northern and Highland regions showed poor uptake of TB-HIV interventions. In HCMC, 303 (27%) of 1110 TB-HIV patients had adverse outcomes, with higher risks observed in those with previously treated TB, those diagnosed as HIV-positive before TB onset and those never placed on cotrimoxazole or ART. Despite improving HIV testing rates and TB-HIV interventions, adverse outcomes in TB-HIV patients remain at about 26%. Characteristics predicting higher risk of adverse outcomes must be addressed if Viet Nam wishes to end the TB epidemic by 2030.

  9. Impact of artifact removal on ChIP quality metrics in ChIP-seq and ChIP-exo data

    PubMed Central

    Carroll, Thomas S.; Liang, Ziwei; Salama, Rafik; Stark, Rory; de Santiago, Ines

    2014-01-01

    With the advent of ChIP-seq multiplexing technologies and the subsequent increase in ChIP-seq throughput, the development of working standards for the quality assessment of ChIP-seq studies has received significant attention. The ENCODE consortium's large scale analysis of transcription factor binding and epigenetic marks as well as concordant work on ChIP-seq by other laboratories has established a new generation of ChIP-seq quality control measures. The use of these metrics alongside common processing steps has however not been evaluated. In this study, we investigate the effects of blacklisting and removal of duplicated reads on established metrics of ChIP-seq quality and show that the interpretation of these metrics is highly dependent on the ChIP-seq preprocessing steps applied. Further to this we perform the first investigation of the use of these metrics for ChIP-exo data and make recommendations for the adaptation of the NSC statistic to allow for the assessment of ChIP-exo efficiency. PMID:24782889

  10. A world-class target for ICDP drilling at Lake Nam Co, Tibetan Plateau, China: progresses and perspectives

    NASA Astrophysics Data System (ADS)

    Zhu, L.; Wang, J.; Daut, G.; Spiess, V.; Haberzettl, T.; Schulze, N.; Ju, J.; Lü, X.; Bergmann, F.; Haberkern, J.; Schwalb, A.; Mäusbacher, R.

    2017-12-01

    Lake Nam Co (ca. 2000 km2, 4718 m a.s.l., maximum depth: 100 m) is located at the interaction zone of the Westerlies and the Indian monsoon on the central Tibetan Plateau. It was part of a mega-lake during Marine Isotope Stage (MIS) 3 before the Last Glacial Maximum. A long term sedimentary record from Nam Co could therefore provide an excellent paleo-environmental sequence for regional and global comparative studies. This will to deepen our understanding of large scale atmospheric circulation shifts and the environmental links between the Tibetan Plateau at low latitudes and the North Atlantic region at high latitudes. A Nam Co deep drilling will fill the gap in two large scale ICDP/IODP drilling transects (N-S: Lake Baikal, Lake Qinghai, Bay of Bengal; W-E: Lake Van, Lake Issyk-Kul, South China Sea, Lake Towuti), which will show the great significance of monsoon dynamics on a long-term scale. Multidisciplinary researches have been conducted since 2005 by a Sino-German cooperative team. The progresses during the last decade are: 1) Detailed bathymetric surveying, including a shallow sediment profiler investigation (Innomar SES 2000 light, ca. 30 m sediment penetration); 2) Paleo-environmental reconstructions covering the past 24 ka; 3) Modern sediment distribution covering the entire lake; 4) Monitoring including water temperature profiles, sediment traps, seasonal airborne pollen collection; 5) Deep seismic survey penetrating up to 800 meters of lake sediments. Based on sediment rates from reference core NC08/01, seismic results show that an age of 500 ka may be reached at 500 m, and >1 Ma at the observed base. Faulting can be clearly detected in the seismic profiles, especially from MIS 5 to early Holocene, and shows the characteristics of normal faults or strike-slip faults. Both rotation of the layers and the close spacing, along with negative and positive offsets of the faults make a transtensional origin of the basin likely. An ICDP workshop proposal was

  11. The Elimination of Illiteracy and the Use of Complementary Education in the Socialist Republic of Viet Nam.

    ERIC Educational Resources Information Center

    United Nations Educational, Scientific, and Cultural Organization, Bangkok (Thailand). Regional Office for Education in Asia and Oceania.

    To counteract the legacy of 80 years of colonial rule in North Viet Nam, President Ho Chi Minh outlined government objectives in the Declaration of Independence in 1945. Major objectives included combatting ignorance and illiteracy. To work toward these objectives, the government established a Department of Popular Education and encouraged…

  12. Examining the Seven-Flag "Chieu Hoi" Pass: A Primary Document from the American War in Viet Nam

    ERIC Educational Resources Information Center

    Engelmann, Ted

    2006-01-01

    During the Viet Nam war, U.S. military helicopters dropped "Chieu Hoi" (safe conduct) passes over suspected enemy locations to encourage enemy soldiers to surrender. This article presents a classroom activity that encourages students to examine a "Chieu Hoi" pass as a primary historical document, identify its various elements,…

  13. Identification of QTL conferring resistance to stripe rust (Puccinia striiformis f. sp. hordei) and leaf rust (Puccinia hordei) in barley using nested association mapping (NAM)

    PubMed Central

    Vatter, Thomas; Maurer, Andreas; Perovic, Dragan; Kopahnke, Doris; Pillen, Klaus

    2018-01-01

    The biotrophic rust fungi Puccinia hordei and Puccinia striiformis are important barley pathogens with the potential to cause high yield losses through an epidemic spread. The identification of QTL conferring resistance to these pathogens is the basis for targeted breeding approaches aiming to improve stripe rust and leaf rust resistance of modern cultivars. Exploiting the allelic richness of wild barley accessions proved to be a valuable tool to broaden the genetic base of resistance of barley cultivars. In this study, SNP-based nested association mapping (NAM) was performed to map stripe rust and leaf rust resistance QTL in the barley NAM population HEB-25, comprising 1,420 lines derived from BC1S3 generation. By scoring the percentage of infected leaf area, followed by calculation of the area under the disease progress curve and the average ordinate during a two-year field trial, a large variability of resistance across and within HEB-25 families was observed. NAM based on 5,715 informative SNPs resulted in the identification of twelve and eleven robust QTL for resistance against stripe rust and leaf rust, respectively. Out of these, eight QTL for stripe rust and two QTL for leaf rust are considered novel showing no overlap with previously reported resistance QTL. Overall, resistance to both pathogens in HEB-25 is most likely due to the accumulation of numerous small effect loci. In addition, the NAM results indicate that the 25 wild donor QTL alleles present in HEB-25 strongly differ in regard to their individual effect on rust resistance. In future, the NAM concept will allow to select and combine individual wild barley alleles from different HEB parents to increase rust resistance in barley. The HEB-25 results will support to unravel the genetic basis of rust resistance in barley, and to improve resistance against stripe rust and leaf rust of modern barley cultivars. PMID:29370232

  14. Accreditation of Viet Nam's Higher Education: Achievements and Challenges after a Dozen Years of Development

    ERIC Educational Resources Information Center

    Nguyen, Huu Cuong; Evers, Colin; Marshall, Stephen

    2017-01-01

    Purpose: The purpose of this paper is to investigate the development of Viet Nam's approach to higher education quality assurance during the past dozen years since its establishment, focusing on the achievements and challenges. Design/methodology/approach: This is a desktop analysis study. The paper analyses the policies and practices related to…

  15. On the Jupiter's ephemeris in the Ch'i-Yao Jang-Tsai-Chüch.

    NASA Astrophysics Data System (ADS)

    Niu, Weixing; Jiang, Xiaoyuan

    Jupiter's ephemeris preserved in the Ch'i-Yao Jang-Tsai-Chüch is interpreted. Then the time and position coordinates of Jupiter's first stationary point, second stationary point, first visibility in the east and last visibility in the west, which recorded in the ephemeris are analysed. The accuracy of the ephemeris is also discussed. Finally, it is identified that the ephemeris has been used as an astrological handbook by Japanese astrologers in 973 - 1132.

  16. Development and genetic characterization of an Advanced Backcross-Nested Association Mapping (AB-NAM) population of wild × cultivated barley

    USDA-ARS?s Scientific Manuscript database

    The ability to access alleles from unadapted germplasm collections is a long-standing problem for geneticists and breeders. Here we developed, characterized, and demonstrated the utility of a wild barley advanced backcross-nested association mapping (AB-NAM) population. We developed this population ...

  17. Iodine status in late pregnancy and psychosocial determinants of iodized salt use in rural northern Viet Nam

    PubMed Central

    Tran, Thach; Biggs, Beverley; Tran, Tuan; Dwyer, Terry; Casey, Gerard; Tho, Dang Hai; Hetzel, Basil

    2011-01-01

    Abstract Objective To establish iodine status among pregnant women in rural northern Viet Nam and explore psychosocial predictors of the use of iodized salt in their households. Methods This prospective study included pregnant women registered in health stations in randomly-selected communes in Ha Nam province. At recruitment (< 20 weeks of gestation), sociodemographic factors, reproductive health, intimate partner relationship, family violence, symptoms of common mental disorders and use of micronutrient supplements were assessed. During a second assessment (> 28 weeks of gestation) a urine specimen was collected to measure urinary iodine concentration (UIC) and iodized salt use was assessed. Predictors were explored through univariable analyses and multivariable linear and logistic regression. Findings The 413 pregnant women who provided data for this study had a median UIC of 70 µg/l; nearly 83% had a UIC lower than the 150 µg/l recommended by the World Health Organization; only 73.6% reported using iodized salt in any form in their households. Iodized salt use was lower among nulliparous women (odds ratio, OR: 0.56; 95% confidence interval, CI: 0.32–0.96); less educated women (OR: 0.34; 95% CI: 0.16–0.71); factory workers or small-scale traders (OR: 0.52; 95% CI: 0.31–0.86), government workers (OR: 0.35; 95% CI: 0.13–0.89) and women with common mental disorders at recruitment (OR: 0.61; 95% CI: 0.38–0.98). Conclusion The decline in the use of iodized salt in Viet Nam since the National Iodine Deficiency Disorders Control Programme was suspended in 2005 has placed pregnant women and their infants in rural areas at risk of iodine deficiency disorders. PMID:22084527

  18. Seroprevalence survey of avian influenza A(H5N1) among live poultry market workers in northern Viet Nam, 2011

    PubMed Central

    Dung, Tham Chi; Dinh, Pham Ngoc; Nam, Vu Sinh; Tan, Luong Minh; Hang, Nguyen Le Khanh; Thanh, Le Thi

    2014-01-01

    Objective Highly pathogenic avian influenza A(H5N1) is endemic in poultry in Viet Nam. The country has experienced the third highest number of human infections with influenza A(H5N1) in the world. A study in Hanoi in 2001, before the epizootic that was identified in 2003, found influenza A(H5N1) specific antibodies in 4% of poultry market workers (PMWs). We conducted a seroprevalence survey to determine the seroprevalence of antibodies to influenza A(H5N1) among PMWs in Hanoi, Thaibinh and Thanhhoa provinces. Methods We selected PMWs from five markets, interviewed them and collected blood samples. These were then tested using a horse haemagglutination inhibition assay and a microneutralization assay with all three clades of influenza A(H5N1) viruses that have circulated in Viet Nam since 2004. Results The overall seroprevalence was 6.1% (95% confidence interval: 4.6–8.3). The highest proportion (7.2%) was found in PMWs in Hanoi, and the majority of seropositive subjects (70.3%) were slaughterers or sellers of poultry. Discussion The continued circulation and evolution of influenza A(H5N1) requires comprehensive surveillance of both human and animal sites throughout the country with follow-up studies on PMWs to estimate the risk of avian–human transmission of influenza A(H5N1) in Viet Nam. PMID:25685601

  19. Rate constants for the reactions of OH with CH3Cl, CH2Cl2, CHCl3, and CH3Br

    NASA Technical Reports Server (NTRS)

    Hsu, K.-J.; Demore, W. B.

    1994-01-01

    Rate constants for the reactions of OH with CH3Cl, CH2Cl2, CHCl3, and CH3Br have been measured by a relative rate technique in which the reaction rate of each compound was compared to that of HFC-152a (CH3CHF2) and (for CH2Cl2) HFC-161 (CH3CH2F). Using absolute rate constants for HFC-152a and HFC-161, which we have determined relative to those for CH4, CH3CCl3, and C2H6, temperature dependent rate constants of both compounds were derived. The derived rate constant for CH3Br is in good agreement with recent absolute measurements. However, for the chloromethanes all the rate constants are lower at atmospheric temperatures than previously reported, especially for CH2Cl2 where the present rate constant is about a factor of 1.6 below the JPL 92-20 value. The new rate constant appears to resolve a discrepancy between the observed atmospheric concentrations and those calculated from the previous rate constant and estimated release rates.

  20. Early marriage and intimate partner violence among adolescents and young adults in Viet Nam.

    PubMed

    Hong Le, Minh Thi; Tran, Thach Duc; Nguyen, Huong Thanh; Fisher, Jane

    2014-03-01

    Research about the association between early marriage and intimate partner violence (IPV) in low-income countries has yielded conflicting evidence. The aim of this study was to describe the prevalence of and associations between early marriage, and IPV among adolescents and young adults in Viet Nam. Secondary analysis of data from the national Survey Assessment of Viet Namese Youth-Round II (SAVY-II) conducted in 2009-2010, which assessed a representative cohort of people aged 14 to 25 years recruited via a systematic household survey was undertaken. Prevalence was established using descriptive statistics. The association between early marriage and IPV was examined using multiple logistic regressions, adjusting for potential risk factors. Of 10,044 participants, 1,701 had ever married and were included in analyses. Early marriage (before age 18), and experiences of verbal, physical, or sexual IPV were more common among females than males. More young married men than women reported experiences of controlling behaviors by their partners. Early marriage, being illiterate, and exposure to sexual abuse were associated with experience of IPV among young females, but not among young males. Poverty and exposure to family violence was associated with IPV in both sexes. Addressing early marriage, low educational opportunities for girls, childhood sexual abuse, family violence, and poverty should be considered in strategies to reduce IPV in Viet Nam.

  1. Collaborative activities and treatment outcomes in patients with HIV-associated tuberculosis in Viet Nam

    PubMed Central

    Nhung, N. V.; Shewade, H. D.; Hoa, N. B.; Harries, A. D.

    2016-01-01

    Setting: The National Tuberculosis (TB) Programme in Viet Nam and Ho Chi Minh City (HCMC). Objectives: To determine 1) at national level between 2011 and 2013, the relationship between human immunodeficiency virus (HIV) testing, uptake of TB-HIV interventions and adverse treatment outcomes among TB-HIV patients; and 2) in HCMC in 2013, patient characteristics associated with adverse outcomes. Design: An ecological study reviewing aggregate nationwide data and a retrospective cohort review in HCMC. Results: Nationwide, from 2011 to 2013, HIV testing increased in TB patients from 58% to 68% and antiretroviral therapy (ART) increased in TB-HIV patients from 54% to 63%. Adverse treatment outcomes in TB-HIV patients increased from 24% to 27%, largely due to transfer out (5–9% increase) and death. The Northern and Highland regions showed poor uptake of TB-HIV interventions. In HCMC, 303 (27%) of 1110 TB-HIV patients had adverse outcomes, with higher risks observed in those with previously treated TB, those diagnosed as HIV-positive before TB onset and those never placed on cotrimoxazole or ART. Conclusion: Despite improving HIV testing rates and TB-HIV interventions, adverse outcomes in TB-HIV patients remain at about 26%. Characteristics predicting higher risk of adverse outcomes must be addressed if Viet Nam wishes to end the TB epidemic by 2030. PMID:27051604

  2. Management and treatment outcomes of patients enrolled in MDR-TB treatment in Viet Nam

    PubMed Central

    Nhung, N. V.; Hoa, N. B.; Thuy, H. T.; Takarinda, K. C.; Tayler-Smith, K.; Harries, A. D.

    2016-01-01

    Setting: The programmatic management of drug-resistant tuberculosis (TB) in Viet Nam has been rapidly scaled up since 2009. Objectives: To document the annual numbers of patients enrolled for multidrug-resistant tuberculosis (MDR-TB) treatment during 2010–2014 and to determine characteristics and treatment outcomes of patients initiating treatment during 2010–2012. Design: A retrospective cohort study using national reports and data from the national electronic data system for drug-resistant TB. Results: The number of patients enrolled annually for MDR-TB treatment increased from 97 in 2010 to 1522 in 2014. The majority of patients were middle-aged men who had pulmonary disease and had failed a retreatment regimen; 77% had received ⩾2 courses of TB treatment. Favourable outcomes (cured and treatment completed) were attained in 73% of patients. Unfavourable outcomes included loss to follow-up (12.5%), death (8%) and failure (6.3%). Having had ⩾2 previous treatment courses and being human immunodeficiency virus-positive were associated with unfavourable outcomes. Conclusion: Increasing numbers of patients are being treated for MDR-TB each year with good treatment outcomes under national programme management in Viet Nam. However, there is a need to increase case detection—currently at 30% of the estimated 5100 MDR-TB cases per year, reduce adverse outcomes and improve monitoring and evaluation. PMID:27051608

  3. Impacts on Breastfeeding Practices of At-Scale Strategies That Combine Intensive Interpersonal Counseling, Mass Media, and Community Mobilization: Results of Cluster-Randomized Program Evaluations in Bangladesh and Viet Nam

    PubMed Central

    Menon, Purnima; Nguyen, Phuong Hong; Saha, Kuntal Kumar; Tran, Lan Mai; Sanghvi, Tina; Hajeebhoy, Nemat; Afsana, Kaosar; Haque, Raisul; Frongillo, Edward A.; Ruel, Marie T.; Rawat, Rahul

    2016-01-01

    Background Despite recommendations supporting optimal breastfeeding, the number of women practicing exclusive breastfeeding (EBF) remains low, and few interventions have demonstrated implementation and impact at scale. Alive & Thrive was implemented over a period of 6 y (2009–2014) and aimed to improve breastfeeding practices through intensified interpersonal counseling (IPC), mass media (MM), and community mobilization (CM) intervention components delivered at scale in the context of policy advocacy (PA) in Bangladesh and Viet Nam. In Bangladesh, IPC was delivered through a large non-governmental health program; in Viet Nam, it was integrated into government health facilities. This study evaluated the population-level impact of intensified IPC, MM, CM, and PA (intensive) compared to standard nutrition counseling and less intensive MM, CM, and PA (non-intensive) on breastfeeding practices in these two countries. Methods and Findings A cluster-randomized evaluation design was employed in each country. For the evaluation sample, 20 sub-districts in Bangladesh and 40 communes in Viet Nam were randomized to either the intensive or the non-intensive group. Cross-sectional surveys (n ~ 500 children 0–5.9 mo old per group per country) were implemented at baseline (June 7–August 29, 2010, in Viet Nam; April 28–June 26, 2010, in Bangladesh) and endline (June 16–August 30, 2014, in Viet Nam; April 20–June 23, 2014, in Bangladesh). Difference-in-differences estimates (DDEs) of impact were calculated, adjusting for clustering. In Bangladesh, improvements were significantly greater in the intensive compared to the non-intensive group for the proportion of women who reported practicing EBF in the previous 24 h (DDE 36.2 percentage points [pp], 95% CI 21.0–51.5, p < 0.001; prevalence in intensive group rose from 48.5% to 87.6%) and engaging in early initiation of breastfeeding (EIBF) (16.7 pp, 95% CI 2.8–30.6, p = 0.021; 63.7% to 94.2%). In Viet Nam, EBF increases

  4. Impacts on Breastfeeding Practices of At-Scale Strategies That Combine Intensive Interpersonal Counseling, Mass Media, and Community Mobilization: Results of Cluster-Randomized Program Evaluations in Bangladesh and Viet Nam.

    PubMed

    Menon, Purnima; Nguyen, Phuong Hong; Saha, Kuntal Kumar; Khaled, Adiba; Kennedy, Andrew; Tran, Lan Mai; Sanghvi, Tina; Hajeebhoy, Nemat; Baker, Jean; Alayon, Silvia; Afsana, Kaosar; Haque, Raisul; Frongillo, Edward A; Ruel, Marie T; Rawat, Rahul

    2016-10-01

    Despite recommendations supporting optimal breastfeeding, the number of women practicing exclusive breastfeeding (EBF) remains low, and few interventions have demonstrated implementation and impact at scale. Alive & Thrive was implemented over a period of 6 y (2009-2014) and aimed to improve breastfeeding practices through intensified interpersonal counseling (IPC), mass media (MM), and community mobilization (CM) intervention components delivered at scale in the context of policy advocacy (PA) in Bangladesh and Viet Nam. In Bangladesh, IPC was delivered through a large non-governmental health program; in Viet Nam, it was integrated into government health facilities. This study evaluated the population-level impact of intensified IPC, MM, CM, and PA (intensive) compared to standard nutrition counseling and less intensive MM, CM, and PA (non-intensive) on breastfeeding practices in these two countries. A cluster-randomized evaluation design was employed in each country. For the evaluation sample, 20 sub-districts in Bangladesh and 40 communes in Viet Nam were randomized to either the intensive or the non-intensive group. Cross-sectional surveys (n ~ 500 children 0-5.9 mo old per group per country) were implemented at baseline (June 7-August 29, 2010, in Viet Nam; April 28-June 26, 2010, in Bangladesh) and endline (June 16-August 30, 2014, in Viet Nam; April 20-June 23, 2014, in Bangladesh). Difference-in-differences estimates (DDEs) of impact were calculated, adjusting for clustering. In Bangladesh, improvements were significantly greater in the intensive compared to the non-intensive group for the proportion of women who reported practicing EBF in the previous 24 h (DDE 36.2 percentage points [pp], 95% CI 21.0-51.5, p < 0.001; prevalence in intensive group rose from 48.5% to 87.6%) and engaging in early initiation of breastfeeding (EIBF) (16.7 pp, 95% CI 2.8-30.6, p = 0.021; 63.7% to 94.2%). In Viet Nam, EBF increases were greater in the intensive group (27.9 pp

  5. Harm reduction and “Clean” community: can Viet Nam have both?

    PubMed Central

    2012-01-01

    The findings of our research show that while police play multiple roles in the fight against drug-related crime, they often perceived their tasks – especially preventing and controlling drug use on the one hand, and supporting harm reduction on the other – as contradictory, and this creates tensions in their work and relations with their communities. Although they are leaders and implementers of harm reduction, not all police know about it, and some remain skeptical or perceive it as contradictory to their main task of fighting drugs. Methadone treatment is seen by some as in competition with their main task of coordinating conventional drug treatment in the rehabilitation center. The history of drug use and the evolution of discourses on drug use in Viet Nam have created these conflicting pressures on police, and thus created contradictory expectations and led to different views and attitudes of police regarding various harm reduction measures. This might aid understanding why, despite the comprehensive and progressive policies on HIV/AIDS and harm reduction in Viet Nam, it is not easy for police to actively and effectively support and be involved in harm reduction at the ground level. To promote the wider acceptance of harm reduction the concept of community safety must be expanded to include community health; harm reduction must be integrated into the “new society” movement; and laws and policies need further revision to reduce contradiction between current drug laws and HIV laws. Harm reduction guidelines for police and other actors need to be disseminated and supported, embodying better ways of working between sectors, and all sectors in the partnership require support for building capacity to contribute to the overall goal. PMID:22769430

  6. Cholinesterase (ChE) response and related mortality among birds fed ChE inhibitors

    USGS Publications Warehouse

    Ludke, J.L.; Hill, E.F.; Dieter, M.P.

    1975-01-01

    Patterns of mortality and inhibition of brain and plasma ChE in birds treated with ChE inhibitors were studied in an attempt to determine the validity of using ChE activity as a monitoring and diagnostic technique. Analysis of brain ChE activity proved to be reliable for diagnosing and monitoring effects of selected ChE inhibitors in birds. Brain ChE inhibition exceeding 20% indicated exposure, and inhibition greater than 50% was sufficient for diagnosing cause of death. Individuals that died from dietary exposure to parathion or carbofuran had brain ChE activities below 55% of normal; although individuals could survive with brain ChE activity lower than 50%. Problems associated with collection, storage, and analysis of tissues for ChE activity are discussed.

  7. Ice chemistry of acetaldehyde reveals competitive reactions in the first step of the Strecker synthesis of alanine: formation of HO-CH(CH3)-NH2 vs. HO-CH(CH3)-CN

    NASA Astrophysics Data System (ADS)

    Fresneau, Aurélien; Danger, Grégoire; Rimola, Albert; Duvernay, Fabrice; Theulé, Patrice; Chiavassa, Thierry

    2015-08-01

    The understanding of compound formation in laboratory simulated astrophysical environments is an important challenge in obtaining information on the chemistry occurring in these environments. We here investigate by means of both laboratory experiments and quantum chemical calculations the ice-based reactivity of acetaldehyde (CH3CHO) with ammonia (NH3) and hydrogen cyanide (HCN) in excess of water (H2O) promoted by temperature. A priori, this study should give information on alanine (2HN-CH(CH3)-COOH) formation (the simplest chiral amino acid detected in meteorites), since these reactions concern the first steps of its formation through the Strecker synthesis. However, infrared spectroscopy, mass spectrometry with HC14N or HC15N isotopologues and B3LYP-D3 results converge to indicate that an H2O-dominated ice containing CH3CHO, NH3 and HCN not only leads to the formation of α-aminoethanol (2HN-CH(CH3)-OH, the product compound of the first step of the Strecker mechanism) and its related polymers (2HN-(CH(CH3)-O)n-H) due to reaction between CH3CHO and NH3, but also to the 2-hydroxypropionitrile (HO­-CH(CH3)-CN) and its related polymers (H-(O-CH(CH3))n-CN) from direct reaction between CH3CHO and HCN. The ratio between these two species depends on the initial NH3/HCN ratio in the ice. Formation of α-aminoethanol is favoured when the NH3 concentration is larger than HCN. We also show that the presence of water is essential for the formation of HO­-CH(CH3)-CN, contrarily to 2HN-CH(CH3)-OH whose formation also takes place in absence of H2O ice. As in astrophysical ices NH3 is more abundant than HCN, formation of α-aminoethanol should consequently be favoured compared to 2-hydroxypropionitrile, thus pointing out α-aminoethanol as a plausible intermediate species for alanine synthesis through the Strecker mechanism in astrophysical ices.

  8. Water incorporation in NAMs after antigorite and chlorite dehydration reactions

    NASA Astrophysics Data System (ADS)

    Padrón-Navarta, José Alberto; Hermann, Jörg

    2014-05-01

    Subduction zones play a fundamental role in the deep water cycle making the Earth unique among other terrestrial planets. Water is incorporated into hydrous minerals during seafloor alteration of the oceanic lithosphere. During subduction of the oceanic lithosphere, dehydration of these hydrous minerals produces a fluid phase. A part of this fluid phase will be recycled back to the Earth's surface through hydrothermal aqueous fluids or through hydrous arc magmas, whereas another part of the water will be transported to the deep mantle by Nominally Anhydrous Minerals (NAMs) such as olivine, pyroxene and garnet. The partitioning of water between these two processes is crucial for our understanding of the mantle-scale water recycling in the Earth. This can be investigated experimentally under water-saturated conditions because this situation is met during dehydration reactions. However relatively low temperature conditions for such reactions make challenging these experiments. An alternative can be found in the natural record. The Alpine Betic-Rif orogen together with Central and Western Alps offer an invaluable diversity of ultramafic lenses that record a significant range of pressure-temperature and cooling rates. Hence these samples portray an excellent data set of 24 samples to survey the transfer of fluids from hydrous phases (brucite, antigorite and chlorite) to NAMs (olivine, orthopyroxene, clinopyroxene and garnet). Well-studied samples from these localities have been selected for water measurement using FTIR spectroscopy. The selected suite comprises the following high-pressure peridotite outcrops: Malenco serpentinite, Cerro del Almirez (1.6-1.9 GPa and 680-710ºC), Alpe Arami (3.2 GPa and 840ºC), Cima di Gagnone (3.0 GPa and 750-800ºC) and Alpe Albion (0.6 GPa and 730ºC). The infrared signature of olivine in all localities contains water (hydroxyl groups) associated to intrinsic defects (mostly point defects related to Ti4+) and extrinsic submicroscopic

  9. Improving hospital death certification in Viet Nam: results of a pilot study implementing an adapted WHO hospital death report form in two national hospitals.

    PubMed

    Walton, Merrilyn; Harrison, Reema; Chevalier, Anna; Esguerra, Esmond; Van Duong, Dang; Chinh, Nguyen Duc; Giang, Huong

    2016-01-01

    Viet Nam does not have a system for the national collection of death data that meets international requirements for mortality reporting. It is identified as a 'no-report' country by the WHO. Verbal autopsy reports are used in the community but exclude deaths in hospitals. This project was undertaken in Bach Mai National General Hospital and Viet Duc Surgical and Trauma Hospital in Viet Nam from 1 March 2013 to 31 March 2015. In phase 1, a modified hospital death report form, consistent with the International Statistical Classification of Diseases and Related Health Problems, 10th Revision, was developed. Small group training in use of the report form was delivered to 427 doctors. In phase two, death data were collected, collated and analysed. In phase three, a random sample (7%) of all report forms was checked for accuracy and completeness against medical records. During the 23 months of the study, 3956 deaths were recorded. Across both hospitals, 222 distinct causes of deaths were recorded. Traumatic cerebral oedema was the immediate cause of death (15% of cases, 575/3956 patients), followed by septic shock (13%, 528/3956), brain compression (11%, 416/3956), intracerebral haemorrhage (8%, 336/3956) and pneumonia (5%, 186/3956); 67% (2639/3956) of patients were discharged home to die and 33% (1314/3956) of deaths were due to a road traffic accident, or injury at home or at work. This study confirms the viability of implementing a death report form system compliant with international standards in hospitals in Viet Nam and provides the foundation for introducing a national death report form scheme. These data are critical to comprehensive knowledge of causes of death in Viet Nam. Death data about patients discharged home to die is presented for the first time, with implications for countries where this is a cultural preference.

  10. New superhindered polydentate polyphosphine ligands P(CH2CH2P(t)Bu2)3, PhP(CH2CH2P(t)Bu2)2, P(CH2CH2CH2P(t)Bu2)3, and their ruthenium(II) chloride complexes.

    PubMed

    Gilbert-Wilson, Ryan; Field, Leslie D; Bhadbhade, Mohan M

    2012-03-05

    The synthesis and characterization of the extremely hindered phosphine ligands, P(CH(2)CH(2)P(t)Bu(2))(3) (P(2)P(3)(tBu), 1), PhP(CH(2)CH(2)P(t)Bu(2))(2) (PhP(2)P(2)(tBu), 2), and P(CH(2)CH(2)CH(2)P(t)Bu(2))(3) (P(3)P(3)(tBu), 3) are reported, along with the synthesis and characterization of ruthenium chloro complexes RuCl(2)(P(2)P(3)(tBu)) (4), RuCl(2)(PhP(2)P(2)(tBu)) (5), and RuCl(2)(P(3)P(3)(tBu)) (6). The bulky P(2)P(3)(tBu) (1) and P(3)P(3)(tBu) (3) ligands are the most sterically encumbered PP(3)-type ligands so far synthesized, and in all cases, only three phosphorus donors are able to bind to the metal center. Complexes RuCl(2)(PhP(2)P(2)(tBu)) (5) and RuCl(2)(P(3)P(3)(tBu)) (6) were characterized by crystallography. Low temperature solution and solid state (31)P{(1)H} NMR were used to demonstrate that the structure of RuCl(2)(P(2)P(3)(tBu)) (4) is probably analogous to that of RuCl(2)(PhP(2)P(2)(tBu)) (5) which had been structurally characterized.

  11. Development and Genetic Characterization of an Advanced Backcross-Nested Association Mapping (AB-NAM) Population of Wild × Cultivated Barley

    PubMed Central

    Nice, Liana M.; Steffenson, Brian J.; Brown-Guedira, Gina L.; Akhunov, Eduard D.; Liu, Chaochih; Kono, Thomas J. Y.; Morrell, Peter L.; Blake, Thomas K.; Horsley, Richard D.; Smith, Kevin P.; Muehlbauer, Gary J.

    2016-01-01

    The ability to access alleles from unadapted germplasm collections is a long-standing problem for geneticists and breeders. Here we developed, characterized, and demonstrated the utility of a wild barley advanced backcross-nested association mapping (AB-NAM) population. We developed this population by backcrossing 25 wild barley accessions to the six-rowed malting barley cultivar Rasmusson. The 25 wild barley parents were selected from the 318 accession Wild Barley Diversity Collection (WBDC) to maximize allelic diversity. The resulting 796 BC2F4:6 lines were genotyped with 384 SNP markers, and an additional 4022 SNPs and 263,531 sequence variants were imputed onto the population using 9K iSelect SNP genotypes and exome capture sequence of the parents, respectively. On average, 96% of each wild parent was introgressed into the Rasmusson background, and the population exhibited low population structure. While linkage disequilibrium (LD) decay (r2 = 0.2) was lowest in the WBDC (0.36 cM), the AB-NAM (9.2 cM) exhibited more rapid LD decay than comparable advanced backcross (28.6 cM) and recombinant inbred line (32.3 cM) populations. Three qualitative traits: glossy spike, glossy sheath, and black hull color were mapped with high resolution to loci corresponding to known barley mutants for these traits. Additionally, a total of 10 QTL were identified for grain protein content. The combination of low LD, negligible population structure, and high diversity in an adapted background make the AB-NAM an important tool for high-resolution gene mapping and discovery of novel allelic variation using wild barley germplasm. PMID:27182953

  12. A multicentre molecular analysis of hepatitis B and blood-borne virus coinfections in Viet Nam.

    PubMed

    Dunford, Linda; Carr, Michael J; Dean, Jonathan; Nguyen, Linh Thuy; Ta Thi, Thu Hong; Nguyen, Binh Thanh; Connell, Jeff; Coughlan, Suzie; Nguyen, Hien Tran; Hall, William W; Thi, Lan Anh Nguyen

    2012-01-01

    Hepatitis B (HBV) infection is endemic in Viet Nam, with up to 8.4 million individuals estimated to be chronically infected. We describe results of a large, multicentre seroepidemiological and molecular study of the prevalence of HBV infection and blood-borne viral coinfections in Viet Nam. Individuals with varying risk factors for infection (n = 8654) were recruited from five centres; Ha Noi, Hai Phong, Da Nang, Khanh Hoa and Can Tho. A mean prevalence rate of 10.7% was observed and levels of HBsAg were significantly higher in injecting drug users (IDUs) (17.4%, n = 174/1000) and dialysis patients (14.3%, n = 82/575) than in lower-risk groups (9.4%; p<0.001). Coinfection with HIV was seen in 28% of HBV-infected IDUs (n = 49/174) and 15.2% of commercial sex workers (CSWs; n = 15/99). HCV infection was present in 89.8% of the HBV-HIV coinfected IDUs (n = 44/49) and 40% of HBV-HIV coinfected CSWs (n = 16/40). Anti-HDV was detected in 10.7% (n = 34/318) of HBsAg positive individuals. Phylogenetic analysis of HBV S gene (n = 187) showed a predominance of genotype B4 (82.6%); genotypes C1 (14.6%), B2 (2.7%) and C5 (0.5%) were also identified. The precore mutation G1896A was identified in 35% of all specimens, and was more frequently observed in genotype B (41%) than genotype C (3%; p<0.0001). In the immunodominant 'a' region of the surface gene, point mutations were identified in 31% (n = 58/187) of sequences, and 2.2% (n = 4/187) and 5.3% (n = 10/187) specimens contained the major vaccine escape mutations G145A/R and P120L/Q/S/T, respectively. 368 HBsAg positive individuals were genotyped for the IL28B SNP rs12979860 and no significant association between the IL28B SNP and clearance of HBsAg, HBV viral load or HBeAg was observed. This study confirms the high prevalence of HBV infection in Viet Nam and also highlights the significant levels of blood-borne virus coinfections, which have important implications for hepatitis-related morbidity and development of effective

  13. The use of a computerized database to monitor vaccine safety in Viet Nam.

    PubMed Central

    Ali, Mohammad; Canh, Gia Do; Clemens, John D.; Park, Jin-Kyung; von Seidlein, Lorenz; Minh, Tan Truong; Thiem, Dinh Vu; Tho, Huu Le; Trach, Duc Dang

    2005-01-01

    Health information systems to monitor vaccine safety are used in industrialized countries to detect adverse medical events related to vaccinations or to prove the safety of vaccines. There are no such information systems in the developing world, but they are urgently needed. A large linked database for the monitoring of vaccine-related adverse events has been established in Khanh Hoa province, Viet Nam. Data collected during the first 2 years of surveillance, a period which included a mass measles vaccination campaign, were used to evaluate the system. For this purpose the discharge diagnoses of individuals admitted to polyclinics and hospitals were coded according to the International Classification of Diseases (ICD)-10 guidelines and linked in a dynamic population database with vaccination histories. A case-series analysis was applied to the cohort of children vaccinated during the mass measles vaccination campaign. The study recorded 107,022 immunizations in a catchment area with a population of 357,458 and confirmed vaccine coverage of 87% or higher for completed routine childhood vaccinations. The measles vaccination campaign immunized at least 86% of the targeted children aged 9 months to 10 years. No medical event was detected significantly more frequently during the 14 days after measles vaccination than before it. The experience in Viet Nam confirmed the safety of a measles vaccination campaign and shows that it is feasible to establish health information systems such as a large linked database which can provide reliable data in a developing country for a modest increase in use of resources. PMID:16193545

  14. ChIA-PET2: a versatile and flexible pipeline for ChIA-PET data analysis

    PubMed Central

    Li, Guipeng; Chen, Yang; Snyder, Michael P.; Zhang, Michael Q.

    2017-01-01

    ChIA-PET2 is a versatile and flexible pipeline for analyzing different types of ChIA-PET data from raw sequencing reads to chromatin loops. ChIA-PET2 integrates all steps required for ChIA-PET data analysis, including linker trimming, read alignment, duplicate removal, peak calling and chromatin loop calling. It supports different kinds of ChIA-PET data generated from different ChIA-PET protocols and also provides quality controls for different steps of ChIA-PET analysis. In addition, ChIA-PET2 can use phased genotype data to call allele-specific chromatin interactions. We applied ChIA-PET2 to different ChIA-PET datasets, demonstrating its significantly improved performance as well as its ability to easily process ChIA-PET raw data. ChIA-PET2 is available at https://github.com/GuipengLi/ChIA-PET2. PMID:27625391

  15. Co-processing CH4 and oxygenates on Mo/H-ZSM-5: 2. CH4-CO2 and CH4-HCOOH mixtures.

    PubMed

    Bedard, Jeremy; Hong, Do-Young; Bhan, Aditya

    2013-08-07

    Co-processing of formic acid or carbon dioxide with CH4 (FA/CH4 = 0.01-0.03 and CO2/CH4 = 0.01-0.03) on Mo/H-ZSM-5 catalysts at 950 K with the prospect of kinetically coupling dehydrogenation and deoxygenation cycles results instead in a two-zone, staged bed reactor configuration consisting of upstream oxygenate/CH4 reforming and downstream CH4 dehydroaromatization. The addition of an oxygenate co-feed (oxygenate/CH4 = 0.01-0.03) causes oxidation of the active molybdenum carbide catalyst while producing CO and H2 until completely converted. Forward rates of C6H6 synthesis are unaffected by the introduction of an oxygenate co-feed after rigorously accounting for the thermodynamic reversibility caused by the H2 produced in oxygenate reforming reactions and the fraction of the active catalyst deemed unavailable for CH4 DHA. All effects of co-processing oxygenates with CH4 can be construed in terms of an approach to equilibrium.

  16. A Self-Sustained Education System for a Developing Country: The Case of the Socialist Republic of Viet Nam.

    ERIC Educational Resources Information Center

    Tran, Dien Ngoc

    Viet Nam's average annual population growth rate is 2.6%, which accounts for a large youth population: 37.7% of the total population is under age 15, compared with an average of 20% in developed or newly industrialized countries. A free basic education for all children is almost impossible to provide. With consideration of the Vietnamese people's…

  17. Prevalence of and risk factors for violent disciplinary practices at home in Viet Nam.

    PubMed

    Cappa, Claudia; Dam, Hang

    2014-02-01

    Data on parenting practices and the use of violence in child rearing remain scarce worldwide, hindering prevention efforts. This study examines disciplinary methods used on children at home in Viet Nam. It is based on data collected from 2010 to 2011 through the fourth round of the Multiple Indicator Cluster Survey (MICS4)-a household survey program supported by the United Nations Children's Fund (UNICEF) that focuses on women and children in low- and middle-income countries. Respondents in the survey were asked 11 questions relating to disciplinary measures used in the preceding month on one randomly selected child (2-14 years old) in each household. A final question about attitudes probed adults' views on the need for physical punishment in child rearing. Univariate and multivariate analyses were conducted to estimate the prevalence of violent and nonviolent forms of discipline, and to identify risk factors associated with violent punishment. Results showed that three in four children in Viet Nam are disciplined through violent means. The exposure of Vietnamese children to violent forms of discipline was significantly associated with varied characteristics of both children and their caregivers. Moreover, the use of violent disciplinary practices on children was strongly associated with positive attitudes toward corporal punishment. Risk factors for violent child discipline identified in this study can inform future interventions to promote positive practices and to protect Vietnamese children against violence in the home.

  18. Effects of Social Class and School Conditions on Educational Enrollment and Achievement of Boys and Girls in Rural Viet Nam

    ERIC Educational Resources Information Center

    Nguyen, Phuong L.

    2006-01-01

    This study examines the effects of parental SES, school quality, and community factors on children's enrollment and achievement in rural areas in Viet Nam, using logistic regression and ordered logistic regression. Multivariate analysis reveals significant differences in educational enrollment and outcomes by level of household expenditures and…

  19. Symptoms and Risk Factors for Stroke in a Community-Based Observational Sample in Viet Nam

    PubMed Central

    Fitzpatrick, Annette L.; Van Ngo, Quang; Ly, Kiet A.; Ton, Thanh G.N.; Longstreth, W.T.; Vo, Tung T; Heitzinger, Kristen; Pham, Chien H.; Tirschwell, David L.

    2013-01-01

    Background Viet Nam is experiencing a health transition from infectious to chronic disease. Data on cardiovascular diseases, including strokes, are limited. Methods Data were randomly collected from six communities in Da Nang, Viet Nam, on participant demographics, medical history, blood pressure, anthropometrics and health behavior using World Health Organization (WHO) guidelines. Stroke symptoms were collected by self-report with the standardized Questionnaire for Verifying Stroke Free Status. Multivariate logistic regression was used to identify factors associated with the presence of stroke symptoms. Results 1,621 adults were examined with a mean age of 52.0 years (± 12.5 years), of which 56.1% were women. 27.3% of the participants were found to have hypertension, 26.2% used tobacco, and 16.1% were overweight. More than two-thirds of the participants with hypertension were unaware of their condition. Almost one fourth of the participants were identified by the questionnaire as previously experiencing at least one stroke symptom. Age, rural residence, and education were associated with the presence of stroke symptoms. Models adjusted for demographics found hypertension, high cholesterol, reported severe chest pain, former smoking, and being overweight to be associated with a higher prevalence of stroke symptoms. Conclusions The high frequency of stroke symptoms in Da Nang calls for further evaluation and interventions to reduce hypertension and other risk factors for chronic disease. PMID:23538875

  20. ChIP-re-ChIP: Co-occupancy Analysis by Sequential Chromatin Immunoprecipitation.

    PubMed

    Beischlag, Timothy V; Prefontaine, Gratien G; Hankinson, Oliver

    2018-01-01

    Chromatin immunoprecipitation (ChIP) exploits the specific interactions between DNA and DNA-associated proteins. It can be used to examine a wide range of experimental parameters. A number of proteins bound at the same genomic location can identify a multi-protein chromatin complex where several proteins work together to regulate gene transcription or chromatin configuration. In many instances, this can be achieved using sequential ChIP; or simply, ChIP-re-ChIP. Whether it is for the examination of specific transcriptional or epigenetic regulators, or for the identification of cistromes, the ability to perform a sequential ChIP adds a higher level of power and definition to these analyses. In this chapter, we describe a simple and reliable method for the sequential ChIP assay.

  1. Anharmonic Effect in CH3CH2C(=O)OCH2CH3 Decomposition

    NASA Astrophysics Data System (ADS)

    Ding, Yang; Song, Liguo; Yao, Li; Xia, Wenwen

    2017-12-01

    In this paper, using the B3LYP functional and CCSD(T) method with 6-311++G** basis set, the harmonic and anharmonic rate constants in the unimolecular dissociation of ethyl propanoate have been calculated using Rice-Ramsperger-Kassel-Marcus theory. The anharmonic rate constants of the title reaction have also been examined, the comparison shows that, the anharmonic effect especially in the case of high total energies and temperature for channels 3 to 6 is significant, so that the anharmonic effect cannot be neglected for unimolecular dissociation reaction of CH3CH2C(=O)OCH2CH3 both in microcanonical and canonical systems.

  2. ChIP-chip.

    PubMed

    Kim, Tae Hoon; Dekker, Job

    2018-05-01

    ChIP-chip can be used to analyze protein-DNA interactions in a region-wide and genome-wide manner. DNA microarrays contain PCR products or oligonucleotide probes that are designed to represent genomic sequences. Identification of genomic sites that interact with a specific protein is based on competitive hybridization of the ChIP-enriched DNA and the input DNA to DNA microarrays. The ChIP-chip protocol can be divided into two main sections: Amplification of ChIP DNA and hybridization of ChIP DNA to arrays. A large amount of DNA is required to hybridize to DNA arrays, and hybridization to a set of multiple commercial arrays that represent the entire human genome requires two rounds of PCR amplifications. The relative hybridization intensity of ChIP DNA and that of the input DNA is used to determine whether the probe sequence is a potential site of protein-DNA interaction. Resolution of actual genomic sites bound by the protein is dependent on the size of the chromatin and on the genomic distance between the probes on the array. As with expression profiling using gene chips, ChIP-chip experiments require multiple replicates for reliable statistical measure of protein-DNA interactions. © 2018 Cold Spring Harbor Laboratory Press.

  3. Violation of Bans on Tobacco Advertising and Promotion at Points of Sale in Viet Nam: Trend from 2009 - 2015.

    PubMed

    Huong, Le Thi Thanh; Long, Tran Khanh; Son, Phung Xuan; Huyen, Do Phuc; Linh, Phan Thuy; Bich, Nguyen Ngoc; Lam, Nguyen Xuan; Anh, Le Vu; Tuyet-Hanh, Tran Thi

    2016-01-01

    Comprehensive bans on tobacco advertising and promotion were introduced through tobacco control legislation in Viet Nam, but it has been established that violations of the bans are very common. This study was conducted to explore the trend in violations of bans on tobacco advertising and promotion at points of sale in Viet Nam in the past six years and to explore any differences in the violation situations before and after the Law on Tobacco Control came into effect on 1st May 2013. Quantitative data were collected through observation of violations of the bans on tobacco advertising and promotion at points of sale in 10 provinces throughout Viet Nam in four survey rounds (2009, 2010, 2011, and 2015). Variation in violation prevalence over time was examined by chi-square test using a Bonferini method. Binary logistic regression was employed to identify the factors that may have influences on different types of violation. A level of significance of p<0.05 was used for all tests in this article. The most common form of violation was the display of more than one pack/one carton of a cigarette brand. Violation of bans on tobacco advertising increased while violations on promotion ban and on displaying tobacco decreased through time. Some factors associated with the tobacco advertising and promotion bans included surveyed years, types of points of sale, regions and areas where the points of sale were located. The enforcement of the bans did not improve even after the issuance and the enactment of the Law on Tobacco Control. This suggests that the monitoring and enforcement of bans on tobacco advertising and promotion at points of sale should be strengthened. Penalties should be strictly applied for violators as indicated in the current tobacco control legislation.

  4. Luminescent Copper(I) Halide Butterfly Dimers Coordinated to [Au(CH3imCH2py)2]BF4 and [Au(CH3imCH2quin)2]BF4

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

    Catalano, V.; Moore, A; Shearer, J

    2009-01-01

    The coordination chemistry of copper(I) halides to the homoleptic, N-heterocyclic carbene Au(I) complexes [Au(CH{sub 3}imCH{sub 2}quin){sub 2}]BF{sub 4} and [Au(CH{sub 3}imCH{sub 2}py){sub 2}]BF{sub 4} was explored. The reaction of CuX (X = Cl, Br, I) with either [Au(CH{sub 3}imCH{sub 2}quin){sub 2}]BF{sub 4} or [Au(CH{sub 3}imCH{sub 2}py){sub 2}]BF{sub 4} produces trimetallic complexes containing Cu{sub 2}X{sub 2}-butterfly copper clusters coordinated to the two imine moieties. The triangular arrangement of the metals places the gold(I) center in close proximity ({approx}2.5-2.6 {angstrom}) to the centroid of the Cu-Cu vector. The Cu-Cu separations vary as a function of bridging halide with the shortest Cu-Cu separationsmore » of {approx}2.5 {angstrom} found in the iodo-complexes and the longest separations of 2.9 {angstrom} found in the bridging chloride complexes. In all six complexes the Au-Cu separations range from {approx}2.8 to 3.0 {angstrom}. In the absence of halides, the dimetallic complex [AuCu(CH{sub 3}imCH{sub 2}py){sub 2}(NCCH{sub 3}){sub 2}](BF{sub 4}){sub 2}, containing a long Au-Cu distance of {approx}4.72 {angstrom} is formed. Additionally, as the byproduct of the reaction of CuBr with [Au(CH{sub 3}imCH{sub 2}quin){sub 2}]BF{sub 4} the deep-red, dimetallic compound, AuCuBr{sub 2}(CH{sub 3}imCH{sub 2}quin){sub 2}, was isolated in very low yield. All of these complexes were studied by NMR spectroscopy, mass spectrometry, and the copper containing species were additionally characterized by X-ray crystallography. In solution the copper centers dissociate from the gold complexes, but as shown by XANES and EXAFS spectroscopy, at low temperature the Cu-Cu linkage is broken, and the individual copper(I) halides reposition themselves to opposite sides of the gold complex while remaining coordinated to one imine moiety. In the solid state all of the complexes are photoluminescent, though the nature of the excited state was not determined.« less

  5. Comparison of hourly surface downwelling solar radiation estimated from MSG-SEVIRI and forecast by the RAMS model with pyranometers over Italy

    NASA Astrophysics Data System (ADS)

    Federico, Stefano; Torcasio, Rosa Claudia; Sanò, Paolo; Casella, Daniele; Campanelli, Monica; Fokke Meirink, Jan; Wang, Ping; Vergari, Stefania; Diémoz, Henri; Dietrich, Stefano

    2017-06-01

    In this paper, we evaluate the performance of two global horizontal solar irradiance (GHI) estimates, one derived from Meteosat Second Generation (MSG) and another from the 1-day forecast of the Regional Atmospheric Modeling System (RAMS) mesoscale model. The horizontal resolution of the MSG-GHI is 3 × 5 km2 over Italy, which is the focus area of this study. For this paper, RAMS has the horizontal resolution of 4 km.The performances of the MSG-GHI estimate and RAMS-GHI 1-day forecast are evaluated for 1 year (1 June 2013-31 May 2014) against data of 12 ground-based pyranometers over Italy spanning a range of climatic conditions, i.e. from maritime Mediterranean to Alpine climate.Statistics for hourly GHI and daily integrated GHI are presented for the four seasons and the whole year for all the measurement sites. Different sky conditions are considered in the analysisResults for hourly data show an evident dependence on the sky conditions, with the root mean square error (RMSE) increasing from clear to cloudy conditions. The RMSE is substantially higher for Alpine stations in all the seasons, mainly because of the increase of the cloud coverage for these stations, which is not well represented at the satellite and model resolutions. Considering the yearly statistics computed from hourly data for the RAMS model, the RMSE ranges from 152 W m-2 (31 %) obtained for Cozzo Spadaro, a maritime station, to 287 W m-2 (82 %) for Aosta, an Alpine site. Considering the yearly statistics computed from hourly data for MSG-GHI, the minimum RMSE is for Cozzo Spadaro (71 W m-2, 14 %), while the maximum is for Aosta (181 W m-2, 51 %). The mean bias error (MBE) shows the tendency of RAMS to over-forecast the GHI, while no specific behaviour is found for MSG-GHI.Results for daily integrated GHI show a lower RMSE compared to hourly GHI evaluation for both RAMS-GHI 1-day forecast and MSG-GHI estimate. Considering the yearly evaluation, the RMSE of daily integrated GHI is at least 9

  6. Decreasing In-home Smoking of Adults—Results from a School-based Intervention Program in Viet Nam

    PubMed Central

    Huong, Le Thi Thanh; Long, Tran Khanh; Anh, Le Vu; Cook, Margaret; Capra, Mike

    2016-01-01

    It is indicated that children are involuntarily exposed to secondhand smoke from adults, mainly at their home environment. This study aimed at describing the effectiveness of the school-based intervention to decrease the in-home smoking situation of adults so as to decrease children's exposure to secondhand smoke at home during the year 2011–2012 in a rural district in Hanoi, Viet Nam. This school-based intervention program (intervention and control group) involved 804 children aged 8 to 11 years from August 2011 to May 2012 in a rural district of Hanoi, Viet Nam. Children were taught in class about the harmful effects of secondhand smoke and about how to negotiate with fathers not to smoke in-home. Then children applied what they learnt, including staying away from secondhand smoke and persuading fathers not to smoke in-home in order to decrease children's exposure to secondhand smoke. Chi square test, t-test and multinominal logistic regression were applied in data analysis. The results showed that children's reported their father's in-home smoking decreased from 83.0% pre-intervention to 59.8% post-intervention (p < 0.001) in the intervention school while no change happened in the control school. The study found that the better changed smoking location of adult smokers as reported by children associated with the school who received intervention activities (adjusted OR = 2.04; 95% CI: 1.28–3.24). Poorer changed attitudes towards secondhand smoke of children associated with a lower percentage of better change in smoking location of their fathers/other adult smokers (aOR = 0.51, 95% CI: 0.28–0.96). Children's poorer changed knowledge towards secondhand smoke also associated with poorer changed smoking location of adult smokers (aOR = 2.88, 95% CI: 1.07–7.76). It is recommended by this study that similar school based intervention approaches should be applied in primary schools in Viet Nam to increase children's awareness on the adverse health effects of

  7. Decreasing In-home Smoking of Adults-Results from a School-based Intervention Program in Viet Nam.

    PubMed

    Huong, Le Thi Thanh; Long, Tran Khanh; Anh, Le Vu; Cook, Margaret; Capra, Mike

    2016-01-01

    It is indicated that children are involuntarily exposed to secondhand smoke from adults, mainly at their home environment. This study aimed at describing the effectiveness of the school-based intervention to decrease the in-home smoking situation of adults so as to decrease children's exposure to secondhand smoke at home during the year 2011-2012 in a rural district in Hanoi, Viet Nam. This school-based intervention program (intervention and control group) involved 804 children aged 8 to 11 years from August 2011 to May 2012 in a rural district of Hanoi, Viet Nam. Children were taught in class about the harmful effects of secondhand smoke and about how to negotiate with fathers not to smoke in-home. Then children applied what they learnt, including staying away from secondhand smoke and persuading fathers not to smoke in-home in order to decrease children's exposure to secondhand smoke. Chi square test, t-test and multinominal logistic regression were applied in data analysis. The results showed that children's reported their father's in-home smoking decreased from 83.0% pre-intervention to 59.8% post-intervention ( p < 0.001) in the intervention school while no change happened in the control school. The study found that the better changed smoking location of adult smokers as reported by children associated with the school who received intervention activities (adjusted OR = 2.04; 95% CI: 1.28-3.24). Poorer changed attitudes towards secondhand smoke of children associated with a lower percentage of better change in smoking location of their fathers/other adult smokers (aOR = 0.51, 95% CI: 0.28-0.96). Children's poorer changed knowledge towards secondhand smoke also associated with poorer changed smoking location of adult smokers (aOR = 2.88, 95% CI: 1.07-7.76). It is recommended by this study that similar school based intervention approaches should be applied in primary schools in Viet Nam to increase children's awareness on the adverse health effects of secondhand

  8. CH-53K Heavy Lift Replacement Helicopter (CH-53K)

    DTIC Science & Technology

    2015-12-01

    Selected Acquisition Report (SAR) RCS: DD-A&T(Q&A)823-390 CH-53K Heavy Lift Replacement Helicopter (CH-53K) As of FY 2017 President’s Budget...December 2015 SAR March 4, 2016 10:04:18 UNCLASSIFIED 4 Col Henry Vanderborght PMA-261 Heavy Lift Helicopters Program Executive Office - Air, Anti...Replacement Helicopter (CH-53K) DoD Component Navy Responsible Office References SAR Baseline (Development Estimate) Defense Acquisition Executive (DAE

  9. Risk Factors for Chronic Disease in Viet Nam: A Review of the Literature

    PubMed Central

    Rao, Chalapati; Nhung, Nguyen Thi Trang; Marks, Geoffrey; Hoa, Nguyen Phuong

    2013-01-01

    Introduction Chronic diseases account for most of the disease burden in low- and middle-income countries, particularly those in Asia. We reviewed literature on chronic disease risk factors in Viet Nam to identify patterns and data gaps. Methods All population-based studies published from 2000 to 2012 that reported chronic disease risk factors were considered. We used standard chronic disease terminology to search PubMed and assessed titles, abstracts, and articles for eligibility for inclusion. We summarized relevant study information in tables listing available studies, risk factors measured, and the prevalence of these risk factors. Results We identified 23 studies conducted before 2010. The most common age range studied was 25 to 64 years. Sample sizes varied, and sample frames were national in 5 studies. A combination of behavioral, physical, and biological risk factors was studied. Being overweight or obese was the most common risk factor studied (n = 14), followed by high blood pressure (n = 11) and tobacco use (n = 10). Tobacco and alcohol use were high among men, and tobacco use may be increasing among Vietnamese women. High blood pressure is common; however, people’s knowledge that they have high blood pressure may be low. A high proportion of diets do not meet international criteria for fruit and vegetable consumption. Prevalence of overweight and obesity is increasing. None of the studies evaluated measured dietary patterns or total caloric intake, and only 1 study measured dietary salt intake. Conclusion Risk factors for chronic diseases are common in Viet Nam; however, more recent and context-specific information is required for planning and monitoring interventions to reduce risk factors and chronic disease in this country. PMID:23306076

  10. First record of a cave species of Euscorpiops Vachon from Viet Nam (Scorpiones, Euscorpiidae, Scorpiopinae).

    PubMed

    Lourenço, Wilson R; Pham, Dinh-Sac

    2013-07-01

    Euscorpiops cavernicola sp. n., belonging to the family Euscorpiidae Laurie, is described on the basis of two male and two female specimens collected in the Hua Ma cave located in the Quang Khe commune, Ba Be district of Bac Kan province in Viet Nam. The new species presents most features exhibited by scorpions within the genus Euscorpiops, however it may represent the first discovered Scorpiopinae species exhibiting certain adaptations to cave life. Copyright © 2013 Académie des sciences. Published by Elsevier SAS. All rights reserved.

  11. Dynamics of the F(-) + CH3I → HF + CH2I(-) Proton Transfer Reaction.

    PubMed

    Zhang, Jiaxu; Xie, Jing; Hase, William L

    2015-12-17

    Direct chemical dynamics simulations, at collision energies Erel of 0.32 and 1.53 eV, were performed to obtain an atomistic understanding of the F(-) + CH3I reaction dynamics. There is only the F(-) + CH3I → CH3F + I(-) bimolecular nucleophilic substitution SN2 product channel at 0.32 eV. Increasing Erel to 1.53 eV opens the endothermic F(-) + CH3I → HF + CH2I(-) proton transfer reaction, which is less competitive than the SN2 reaction. The simulations reveal proton transfer occurs by two direct atomic-level mechanisms, rebound and stripping, and indirect mechanisms, involving formation of the F(-)···HCH2I complex and the roundabout. For the indirect trajectories all of the CH2I(-) is formed with zero-point energy (ZPE), while for the direct trajectories 50% form CH2I(-) without ZPE. Without a ZPE constraint for CH2I(-), the reaction cross sections for the rebound, stripping, and indirect mechanisms are 0.2 ± 0.1, 1.2 ± 0.4, and 0.7 ± 0.2 Å(2), respectively. Discarding trajectories that do not form CH2I(-) with ZPE reduces the rebound and stripping cross sections to 0.1 ± 0.1 and 0.7 ± 0.5 Å(2). The HF product is formed rotationally and vibrationally unexcited. The average value of J is 2.6 and with histogram binning n = 0. CH2I(-) is formed rotationally excited. The partitioning between CH2I(-) vibration and HF + CH2I(-) relative translation energy depends on the treatment of CH2I(-) ZPE. Without a CH2I(-) ZPE constraint the energy partitioning is primarily to relative translation with little CH2I(-) vibration. With a ZPE constraint, energy partitioning to CH2I(-) rotation, CH2I(-) vibration, and relative translation are statistically the same. The overall F(-) + CH3I rate constant at Erel of both 0.32 and 1.53 eV is in good agreement with experiment and negligibly affected by the treatment of CH2I(-) ZPE, since the SN2 reaction is the major contributor to the total reaction rate constant. The potential energy surface and reaction dynamics for F

  12. Capture and dissociation in the complex-forming CH + H2 → CH2 + H, CH + H2 reactions.

    PubMed

    González, Miguel; Saracibar, Amaia; Garcia, Ernesto

    2011-02-28

    The rate coefficients for the capture process CH + H(2)→ CH(3) and the reactions CH + H(2)→ CH(2) + H (abstraction), CH + H(2) (exchange) have been calculated in the 200-800 K temperature range, using the quasiclassical trajectory (QCT) method and the most recent global potential energy surface. The reactions, which are of interest in combustion and in astrochemistry, proceed via the formation of long-lived CH(3) collision complexes, and the three H atoms become equivalent. QCT rate coefficients for capture are in quite good agreement with experiments. However, an important zero point energy (ZPE) leakage problem occurs in the QCT calculations for the abstraction, exchange and inelastic exit channels. To account for this issue, a pragmatic but accurate approach has been applied, leading to a good agreement with experimental abstraction rate coefficients. Exchange rate coefficients have also been calculated using this approach. Finally, calculations employing QCT capture/phase space theory (PST) models have been carried out, leading to similar values for the abstraction rate coefficients as the QCT and previous quantum mechanical capture/PST methods. This suggests that QCT capture/PST models are a good alternative to the QCT method for this and similar systems.

  13. Towards a Lifelong Learning Society through Reading Promotion: Opportunities and Challenges for Libraries and Community Learning Centres in Viet Nam

    ERIC Educational Resources Information Center

    Hossain, Zakir

    2016-01-01

    The government of Viet Nam has made a commitment to build a Lifelong Learning Society by 2020. A range of related initiatives have been launched, including the Southeast Asian Ministers of Education Organization Centre for Lifelong Learning (SEAMEO CELLL) and "Book Day"--a day aimed at encouraging reading and raising awareness of its…

  14. A Multicentre Molecular Analysis of Hepatitis B and Blood-Borne Virus Coinfections in Viet Nam

    PubMed Central

    Dunford, Linda; Carr, Michael J.; Dean, Jonathan; Nguyen, Linh Thuy; Ta Thi, Thu Hong; Nguyen, Binh Thanh; Connell, Jeff; Coughlan, Suzie; Nguyen, Hien Tran; Hall, William W.; Thi, Lan Anh Nguyen

    2012-01-01

    Hepatitis B (HBV) infection is endemic in Viet Nam, with up to 8.4 million individuals estimated to be chronically infected. We describe results of a large, multicentre seroepidemiological and molecular study of the prevalence of HBV infection and blood-borne viral coinfections in Viet Nam. Individuals with varying risk factors for infection (n = 8654) were recruited from five centres; Ha Noi, Hai Phong, Da Nang, Khanh Hoa and Can Tho. A mean prevalence rate of 10.7% was observed and levels of HBsAg were significantly higher in injecting drug users (IDUs) (17.4%, n = 174/1000) and dialysis patients (14.3%, n = 82/575) than in lower-risk groups (9.4%; p<0.001). Coinfection with HIV was seen in 28% of HBV-infected IDUs (n = 49/174) and 15.2% of commercial sex workers (CSWs; n = 15/99). HCV infection was present in 89.8% of the HBV-HIV coinfected IDUs (n = 44/49) and 40% of HBV-HIV coinfected CSWs (n = 16/40). Anti-HDV was detected in 10.7% (n = 34/318) of HBsAg positive individuals. Phylogenetic analysis of HBV S gene (n = 187) showed a predominance of genotype B4 (82.6%); genotypes C1 (14.6%), B2 (2.7%) and C5 (0.5%) were also identified. The precore mutation G1896A was identified in 35% of all specimens, and was more frequently observed in genotype B (41%) than genotype C (3%; p<0.0001). In the immunodominant ‘a’ region of the surface gene, point mutations were identified in 31% (n = 58/187) of sequences, and 2.2% (n = 4/187) and 5.3% (n = 10/187) specimens contained the major vaccine escape mutations G145A/R and P120L/Q/S/T, respectively. 368 HBsAg positive individuals were genotyped for the IL28B SNP rs12979860 and no significant association between the IL28B SNP and clearance of HBsAg, HBV viral load or HBeAg was observed. This study confirms the high prevalence of HBV infection in Viet Nam and also highlights the significant levels of blood-borne virus coinfections, which have important implications for

  15. Consequences of gestational diabetes in an urban hospital in Viet Nam: a prospective cohort study.

    PubMed

    Hirst, Jane E; Tran, Thach S; Do, My An T; Morris, Jonathan M; Jeffery, Heather E

    2012-01-01

    Gestational diabetes mellitus (GDM) is increasing and is a risk for type 2 diabetes. Evidence supporting screening comes mostly from high-income countries. We aimed to determine prevalence and outcomes in urban Viet Nam. We compared the proposed International Association of the Diabetes and Pregnancy Study Groups (IADPSG) criterion, requiring one positive value on the 75-g glucose tolerance test, to the 2010 American Diabetes Association (ADA) criterion, requiring two positive values. We conducted a prospective cohort study in Ho Chi Minh City, Viet Nam. Study participants were 2,772 women undergoing routine prenatal care who underwent a 75-g glucose tolerance test and interview around 28 (range 24-32) wk. GDM diagnosed by the ADA criterion was treated by local protocol. Women with GDM by the IADPSG criterion but not the ADA criterion were termed "borderline" and received standard care. 2,702 women (97.5% of cohort) were followed until discharge after delivery. GDM was diagnosed in 164 participants (6.1%) by the ADA criterion, 550 (20.3%) by the IADPSG criterion. Mean body mass index was 20.45 kg/m(2) in women with out GDM, 21.10 in women with borderline GDM, and 21.81 in women with GDM, p<0.001. Women with GDM and borderline GDM were more likely to deliver preterm, with adjusted odds ratios (aORs) of 1.49 (95% CI 1.16-1.91) and 1.52 (1.03-2.24), respectively. They were more likely to have clinical neonatal hypoglycaemia, aORs of 4.94 (3.41-7.14) and 3.34 (1.41-7.89), respectively. For large for gestational age, the aORs were 1.16 (0.93-1.45) and 1.31 (0.96-1.79), respectively. There was no significant difference in large for gestational age, death, severe birth trauma, or maternal morbidity between the groups. Women with GDM underwent more labour inductions, aOR 1.51 (1.08-2.11). Choice of criterion greatly affects GDM prevalence in Viet Nam. Women with GDM by the IADPSG criterion were at risk of preterm delivery and neonatal hypoglycaemia, although this criterion

  16. Sensitivity, completeness and agreement of the tuberculosis electronic system in Ho Chi Minh City, Viet Nam.

    PubMed

    Thai, L H; Nhat, L M; Shah, N; Lyss, S; Ackers, M

    2017-12-21

    Setting: Since 2011, tuberculosis (TB) clinics in Ho Chi Minh City (HCMC), Viet Nam, have been entering data from a paper-based TB treatment register into an electronic database known as VITIMES (Viet Nam TB Information Management Electronic System), which is currently used in parallel with the paper system. Objective: To evaluate the sensitivity, completeness and agreement of data in VITIMES with that of paper-based registers among TB patients co-infected with the human immunodeficiency virus (HIV) being treated for TB in HCMC. Design: This was a retrospective data review of all TB-HIV patients receiving anti-tuberculosis treatment in each of the 24 district TB clinics in HCMC in 2013. Data were abstracted from the paper-based TB treatment registers at district level and extracted electronically at the provincial level. Records were matched based on name, age and address. The sensitivity, completeness and agreement of the electronic data were compared with data from the paper system. Results: The findings showed that the electronic system had high sensitivity (99.2%), high completeness (87-99%) and high agreement (κ 0.78-0.97) for all variables. Conclusion: The results of this study suggest that data are being correctly entered into VITIMES and that patient data can be directly entered into VITIMES instead of having a parallel, paper-based system.

  17. Sensitivity, completeness and agreement of the tuberculosis electronic system in Ho Chi Minh City, Viet Nam

    PubMed Central

    Nhat, L. M.; Shah, N.; Lyss, S.; Ackers, M.

    2017-01-01

    Setting: Since 2011, tuberculosis (TB) clinics in Ho Chi Minh City (HCMC), Viet Nam, have been entering data from a paper-based TB treatment register into an electronic database known as VITIMES (Viet Nam TB Information Management Electronic System), which is currently used in parallel with the paper system. Objective: To evaluate the sensitivity, completeness and agreement of data in VITIMES with that of paper-based registers among TB patients co-infected with the human immunodeficiency virus (HIV) being treated for TB in HCMC. Design: This was a retrospective data review of all TB-HIV patients receiving anti-tuberculosis treatment in each of the 24 district TB clinics in HCMC in 2013. Data were abstracted from the paper-based TB treatment registers at district level and extracted electronically at the provincial level. Records were matched based on name, age and address. The sensitivity, completeness and agreement of the electronic data were compared with data from the paper system. Results: The findings showed that the electronic system had high sensitivity (99.2%), high completeness (87–99%) and high agreement (κ 0.78–0.97) for all variables. Conclusion: The results of this study suggest that data are being correctly entered into VITIMES and that patient data can be directly entered into VITIMES instead of having a parallel, paper-based system. PMID:29584795

  18. Can health systems be enhanced for optimal health services through disease-specific programs? Results of field studies in Viet Nam and Cambodia.

    PubMed

    Egami, Y; Fujita, N; Akashi, H; Matsumoto, Y; Ohara, H; Takeuchi, M

    2012-02-01

    Developing better health systems is the key to delivering optimal health services, although more evidence of effective strategies to do so is needed. Field surveys were conducted in Viet Nam and Cambodia to identify best practices in addressing health system bottlenecks to scale up disease control programs. The two countries were compared over time using a framework for analysis developed by the authors. In Viet Nam, a health system was in place for decades at the central to municipal levels, although it was fragile until the 1990s, when the government started taking measures. In Cambodia, the previous health system had been destroyed during previous internal conflict. In the post-conflict period, the health system was rebuilt with support for programs followed by centralization of health services. In different settings, different measures were taken to deal with similar bottlenecks. In Cambodia, vertical programs were dominant, so the government sought to centralize drug management to deal with shortages of essential drugs, while Viet Nam sought to mobilize resources to ensure drug distribution at all levels. This study shows there is no single successful approach to health systems, and a systemic approach needs to be taken because elimination of one bottleneck may reveal another. Efforts to enhance disease-specific programs may not always contribute to overall enhancement of the health system, and the best possible approach may not be the same in different countries. Further study is needed to explore common issues and principles for effective strategies to enhance health systems in different contexts.

  19. Conformational and spectroscopic study of xanthogen ethyl formates, ROC(S)SC(O)OCH2CH3. Isolation of CH3CH2OC(O)SH

    NASA Astrophysics Data System (ADS)

    Juncal, Luciana C.; Cozzarín, Melina V.; Romano, Rosana M.

    2015-03-01

    ROC(S)SC(O)OCH2CH3, with R = CH3sbnd , (CH3)2CHsbnd and CH3(CH2)2sbnd , were obtained through the reaction between potassium xanthate salts, ROC(S)SK, and ethyl chloroformate, ClC(O)OCH2CH3. The liquid compounds were identified and characterized by 1H and 13C NMR and mass spectrometry. The conformations adopted by the molecules were studied by DFT methods. 6 conformers were theoretically predicted for R = CH3sbnd and (CH3)2CHsbnd , while the conformational flexibility of the n-propyl substituent increases the total number of feasible rotamers to 21. For the three molecules, the conformers can be associated in 3 groups, being the most stable the AS forms - the Cdbnd S double bond anti (A) with respect to the Csbnd S single bond and the Ssbnd C single bond syn (S) with respect to the Cdbnd O double bond - followed by AA and SS conformers. The vibrational spectra were interpreted in terms of the predicted conformational equilibrium, presenting the ν(Cdbnd O) spectral region signals corresponding to the three groups of conformers. A moderated pre-resonance Raman enhancement of the ν(Cdbnd S) vibrational mode of CH3(CH2)2OC(S)SC(O)OCH2CH3 was detected, when the excitation radiation approaches the energy of a n → π∗ electronic transition associated with the Cdbnd S chromophore. UV-visible spectra in different solvents were measured and interpreted in terms of TD-DFT calculations. The unknown molecule CH3CH2OC(O)SH was isolated by the UV-visible photolysis of CH3OC(S)SC(O)OCH2CH3 isolated in Ar matrix, and also obtained as a side-product of the reaction between potassium xanthate salts, ROC(S)SK, and ethyl chloroformate, ClC(O)OCH2CH3.

  20. Thermal decomposition of ethanol. 4. Ab initio chemical kinetics for reactions of H atoms with CH3CH2O and CH3CHOH radicals.

    PubMed

    Xu, Z F; Xu, Kun; Lin, M C

    2011-04-21

    The potential energy surfaces of H-atom reactions with CH(3)CH(2)O and CH(3)CHOH, two major radicals in the decomposition and oxidation of ethanol, have been studied at the CCSD(T)/6-311+G(3df,2p) level of theory with geometric optimization carried out at the BH&HLYP/6-311+G(3df,2p) level. The direct hydrogen abstraction channels and the indirect association/decomposition channels from the chemically activated ethanol molecule have been considered for both reactions. The rate constants for both reactions have been calculated at 100-3000 K and 10(-4) Torr to 10(3) atm Ar pressure by microcanonical VTST/RRKM theory with master equation solution for all accessible product channels. The results show that the major product channel of the CH(3)CH(2)O + H reaction is CH(3) + CH(2)OH under atmospheric pressure conditions. Only at high pressure and low temperature, the rate constant for CH(3)CH(2)OH formation by collisonal deactivation becomes dominant. For CH(3)CHOH + H, there are three major product channels; at high temperatures, CH(3)+CH(2)OH production predominates at low pressures (P < 100 Torr), while the formation of CH(3)CH(2)OH by collisional deactivation becomes competitive at high pressures and low temperatures (T < 500 K). At high temperatures, the direct hydrogen abstraction reaction producing CH(2)CHOH + H(2) becomes dominant. Rate constants for all accessible product channels in both systems have been predicted and tabulated for modeling applications. The predicted value for CH(3)CHOH + H at 295 K and 1 Torr pressure agrees closely with available experimental data. For practical modeling applications, the rate constants for the thermal unimolecular decomposition of ethanol giving key accessible products have been predicted; those for the two major product channels taking place by dehydration and C-C breaking agree closely with available literature data.

  1. Patterns of the utilization of prenatal diagnosis services among pregnant women, their satisfaction and its associated factors in Viet Nam.

    PubMed

    Doan, Duong Thi Thuy; Nguyen, Huong Thi Thu; Bui, Ha Thi Thu

    2017-02-01

    This study aimed at understanding the patterns of the utilization of prenatal diagnostic (PND) services among pregnant women, their satisfaction and its associated factors at three regional prenatal diagnostic centres in Viet Nam. A cross-sectional design was used, with a consecutive sampling method to recruit pregnant women who used PND services at the three biggest regional PND services centres in Viet Nam between January and June, 2014. A total of 298 participants, about 100 participants per centre were interviewed and included in data analysis. Descriptive analyses and logistic regression methods were applied to identify association between satisfaction of women and their socio-economic characteristics. 80% of pregnant women received counselling on PND services, whilst 90% received ultrasonography services; 65.4% were satisfied with the PND services they used. Pregnant women, who were in a lower income group and received counselling but did not receive ultrasonography, were more likely to have higher satisfaction levels of PND services. A process to ensure that every pregnant woman receives sufficient PND counselling before and after receiving PND testing must be given careful and thorough consideration.

  2. Ab Initio Chemical Kinetics for the CH3 + O((3)P) Reaction and Related Isomerization-Decomposition of CH3O and CH2OH Radicals.

    PubMed

    Xu, Z F; Raghunath, P; Lin, M C

    2015-07-16

    The kinetics and mechanism of the CH3 + O reaction and related isomerization-decomposition of CH3O and CH2OH radicals have been studied by ab initio molecular orbital theory based on the CCSD(T)/aug-cc-pVTZ//CCSD/aug-cc-pVTZ, CCSD/aug-cc-pVDZ, and G2M//B3LYP/6-311+G(3df,2p) levels of theory. The predicted potential energy surface of the CH3 + O reaction shows that the CHO + H2 products can be directly generated from CH3O by the TS3 → LM1 → TS7 → LM2 → TS4 path, in which both LM1 and LM2 are very loose and TS7 is roaming-like. The result for the CH2O + H reaction shows that there are three low-energy barrier processes including CH2O + H → CHO + H2 via H-abstraction and CH2O + H → CH2OH and CH2O + H → CH3O by addition reactions. The predicted enthalpies of formation of the CH2OH and CH3O radicals at 0 K are in good agreement with available experimental data. Furthermore, the rate constants for the forward and some key reverse reactions have been predicted at 200-3000 K under various pressures. Based on the new reaction pathway for CH3 + O, the rate constants for the CH2O + H and CHO + H2 reactions were predicted with the microcanonical variational transition-state/Rice-Ramsperger-Kassel-Marcus (VTST/RRKM) theory. The predicted total and individual product branching ratios (i.e., CO versus CH2O) are in good agreement with experimental data. The rate constant for the hydrogen abstraction reaction of CH2O + H has been calculated by the canonical variational transition-state theory with quantum tunneling and small-curvature corrections to be k(CH2O + H → CHO + H2) = 2.28 × 10(-19) T(2.65) exp(-766.5/T) cm(3) molecule(-1) s(-1) for the 200-3000 K temperature range. The rate constants for the addition giving CH3O and CH2OH and the decomposition of the two radicals have been calculated by the microcanonical RRKM theory with the time-dependent master equation solution of the multiple quantum well system in the 200-3000 K temperature range at 1 Torr to

  3. Electron spin resonance of (CO 2 H)CH 2 CH 2 CH(CO 2 H) in irradiated glutaric acid

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

    Horsfield, A.; Morton, J. R.; Whiffen, D. H.

    It is concluded from electron spin resonance spectra that the radical (CO 2 H)CH 2 CH 2 CH(CO 2 H) remains trapped in a glutaric acid crystal after gamma -irradiation. This radical is found in two different conformations. Approximate hyperfine coupling constants are given for each, although exact interpretation is hindered by the overlapping of spectra. Reasons for the formation of the two forms of the radical are discussed.

  4. On the formation of the ·CH 2CH 2CH=NH 2+ distonic radical cation upon ionization of cyclopropylamine and allylamine

    NASA Astrophysics Data System (ADS)

    Nguyen, Minh Tho; Creve, Steven; Ha, Tae-Kyu

    1998-08-01

    Ab initio molecular orbital and density functional theory calculations have been applied to determine the relative stability of the cyclopropylamine 1 and allylamine (CH 2=CHCH 2NH 2+·2) radical cations and their isomers. It is confirmed that, upon ionization, 1 undergoes barrier-free ring-opening giving the distonic species ·CH 2CH 2CH=NH 2+3. 2 also rearranges by a 1,2-H-shift to the more stable 3 (by 70 kJ/mol) which is, however, less stable than the 1-aminopropene ion (CH 3-CH=CH-NH 2+·4) by 60 kJ/mol. The transition structure TS 2/3 lies 40 kJ/mol higher in energy than TS 3/4. Although QCISD and B3LYP calculations of isotropic hyperfine coupling constants agree reasonably with observed values, supporting the presence of the distonic 3 in ESR matrix experiments, the exclusive observation of 3, but not 4, is intriguing. This emphasizes the role of the matrix in stabilizing 3.

  5. Rate Constants for the Reactions of OH with CH(sub 3)Cl, CH(sub 2) C1(sub 2), CHC1(sub 3)and CH(sub 3)Br

    NASA Technical Reports Server (NTRS)

    Hsu, H-J.; DeMore, W.

    1994-01-01

    Rate constants for the reactions of OH with CH3C1, CH2Cl2, CHCl3 and CH3Br have been measured by a relative rate technique in which the reaction rate of each compound was compared to that of HFC-152a (CH3CHF2)and for CH2Cl2, HFC-161 (CH3CH2F).

  6. Low-Temperature Hydrocarbon Photochemistry: CH3 + CH3 Recombination in Giant Planet Atmospheres

    NASA Technical Reports Server (NTRS)

    Smith, Gregory P.; Huestis, David L.

    2002-01-01

    Planetary emissions of the methyl radical CH3 were observed for the first time in 1998 on Saturn and Neptune by the ISO (Infrared Space Observatory) mission satellite. CH3 is produced by VUV photolysis of CH4 and is the key photochemical intermediate leading complex organic molecules on the giant planets and moons. The CH3 emissions from Saturn were unexpectedly weak. A suggested remedy is to increase the rate of the recombination reaction CH3 + CH3 + H2 --> C2H6 + H2 at 140 K to a value at least 10 times that measured at room temperature in rare gases, but within the range of disagreeing theoretical expressions at low temperature. We are performing laboratory experiments at low temperature and very low pressure. The experiments are supported by RRKM theoretical modeling that is calibrated using the extensive combustion literature.

  7. Unusual reaction paths of SN2 nucleophile substitution reactions CH4 + H- → CH4 + H- and CH4 + F- → CH3F + H-: Quantum chemical calculations

    NASA Astrophysics Data System (ADS)

    Minyaev, Ruslan M.; Quapp, Wolfgang; Schmidt, Benjamin; Getmanskii, Ilya V.; Koval, Vitaliy V.

    2013-11-01

    Quantum chemical (CCSD(full)/6-311++G(3df,3pd), CCSD(T)(full)/6-311++G(3df,3pd)) and density function theory (B3LYP/6-311++G(3df,3pd)) calculations were performed for the SN2 nucleophile substitution reactions CH4 + H- → CH4 + H- and CH4 + F- → CH3F + H-. The calculated gradient reaction pathways for both reactions have an unusual behavior. An unusual stationary point of index 2 lies on the gradient reaction path. Using Newton trajectories for the reaction path, we can detect VRI point at which the reaction path branches.

  8. Reflected shock tube studies of high-temperature rate constants for OH + CH4 --> CH3 + H2O and CH3 + NO2 --> CH3O + NO.

    PubMed

    Srinivasan, N K; Su, M-C; Sutherland, J W; Michael, J V

    2005-03-10

    The reflected shock tube technique with multipass absorption spectrometric detection of OH radicals at 308 nm has been used to study the reactions OH + CH(4) --> CH(3) + H(2)O and CH(3) + NO(2) --> CH(3)O + NO. Over the temperature range 840-2025 K, the rate constants for the first reaction can be represented by the Arrhenius expression k = (9.52 +/- 1.62) x 10(-11) exp[(-4134 +/- 222 K)/T] cm(3) molecule(-1) s(-1). Since this reaction is important in both combustion and atmospheric chemistry, there have been many prior investigations with a variety of techniques. The present results extend the temperature range by 500 K and have been combined with the most accurate earlier studies to derive an evaluation over the extended temperature range 195-2025 K. A three-parameter expression describes the rate behavior over this temperature range, k = (1.66 x 10(-18))T(2.182) exp[(-1231 K)/T] cm(3) molecule(-1) s(-1). Previous theoretical studies are discussed, and the present evaluation is compared to earlier theoretical estimates. Since CH(3) radicals are a product of the reaction and could cause secondary perturbations in rate constant determinations, the second reaction was studied by OH radical production from the fast reactions CH(3)O --> CH(2)O + H and H + NO(2) --> OH + NO. The measured rate constant is 2.26 x 10(-11) cm(3) molecule(-1) s(-1) and is not dependent on temperature from 233 to 1700 K within experimental error.

  9. Total cross sections of electron scattering by molecules NF3, PF3, N(CH3)3, P(CH3)3, NH(CH3)2, PH(CH3)2, NH2CH3 and PH2CH3 at 30-5000 eV

    NASA Astrophysics Data System (ADS)

    Shi, D. H.; Sun, J. F.; Zhu, Z. L.; Liu, Y. F.

    2010-04-01

    Total cross sections of electron scattering by eight molecules NF3, PF3, N(CH3)3, P(CH3)3, NH(CH3)2, PH(CH3)2, NH2CH3 and PH2CH3, which have some structural similarities, are calculated at the Hartree-Fork level by the modified additivity rule approach [D.H. Shi, J.F. Sun, Z.L. Zhu, H. Ma, Y.F. Liu, Eur. Phys. J. D 45, 253 (2007); D.H. Shi, J.F. Sun, Y.F. Liu, Z.L. Zhu, X.D. Yang, Chin. Opt. Lett. 4, 192 (2006)]. The modified additivity rule approach takes into considerations that the contributions of the geometric shielding effect vary as the energy of incident electrons, the dimension of target molecule, the number of electrons in the molecule and the number of atoms constituting the molecule. The present investigations cover the impact energy range from 30 to 5000 eV. The quantitative total cross sections are compared with those obtained by experiments and other theories. Excellent agreement is observed even at energies of several tens of eV. It shows that the modified additivity rule approach is applicable to carry out the total cross section calculations of electron scattering by these molecules at intermediate and high energies, in particular over the energy range above 80 eV or so. It proves that the microscopic molecular properties, such as the geometrical size of the target and the number of atoms constituting the molecule, are of crucial importance in the TCS calculations. The new results for PH(CH3)2 and PH2CH3 are also presented at energies from 30 to 5000 eV, although no experimental and theoretical data are available for comparison. In the present calculations, the atoms are still represented by the spherical complex optical potential, which is composed of static, exchange, polarization and absorption terms.

  10. Two-wavelength single laser CH and CH(4) imaging in a lifted turbulent diffusion flame.

    PubMed

    Namazian, M; Schmitt, R L; Long, M B

    1988-09-01

    A new technique has been developed which allows simultaneous 2-D mapping of CH and CH 4 in a turbulent methane flame. A flashlamp-pumped dye laser using two back mirrors produces output at 431.5 and 444 nm simultaneously. The 431.5-nm line is used to excite the (0, 0) band of the A(2)Delta-X(2)Pi system of CH, and the fluorescence of the (0, 1) transition is observed at 489 nm. Coincidentally, the spontaneous Raman scattering from CH(4) also occurs near 489 nm for a 431.5-nm excitation. To separate the CH(4) and CH contributions, the 444-nm line is used to produce a spontaneous Raman signal from CH(4) that is spectrally separated from the CH fluorescence. Subtraction of the signals generated by the 431.5- and 444-nm wavelength beams yields separate measurements of CH(4) and CH. Raman-scattered light records the instantaneous distribution of the fuel, and simultaneously the CH fluorescence indicates the location of the flame zone. The resulting composite images provide important insight on the interrelationship between fuel-air mixing and subsequent combustion.M. Namazian is with Altex Technologies Corporation, 109 Via De Tesoros, Los Gatos, California 95030; R. L. Schmitt is with Sandia National Laboratories, Combustion Research Facility, Livermore, California 94550; and M. B. Long is with Yale University, Department of Mechanical Engineering, New Haven, Connecticut 06520.

  11. Electron driven processes in sulphur containing compounds CH3SCH3 and CH3SSCH3

    NASA Astrophysics Data System (ADS)

    Kopyra, Janina; Władziński, Jakub

    2015-06-01

    Dissociative electron attachment to gas phase dimethyl sulphide (CH3SCH3) and dimethyl disulphide (CH3SSCH3) has been studied by means of a crossed beams apparatus. Cleavage of the C-S bond within CH3SCH3 and the S-S bond within CH3SSCH3 is observed within a resonance in the energy range below 2 eV and visible preferentially via the appearance of the fragment CH2S-. The striking finding is that the intensity of CH2S- generated from CH3SSCH3 is more than two orders of magnitude higher than the intensity of the respective anionic fragment generated from CH3SCH3. Our results clearly demonstrate that the CH3SSCH3 molecule, which contains disulphide bridge is substantially more sensitive towards electron attachment resulting mainly in dissociation along the S-S bridge.

  12. Scaled Hartree-Fock force field calculations for organothallium compounds: Normal-mode analysis for TlCH sub 3 Tl(CH sub 3 ) sub 2 sup + , Tl(CH sub 3 ) sub 3 , Tl(CH sub 3 ) sub 2 Br, and Tl(CH sub 3 ) sub 4 sup minus

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

    Schwerdtfeger, P.; Bowmaker, G.A.; Boyd, P.D.W.

    1990-02-01

    In a recent paper we presented Hartree-Fock (HF) calculations for aliphatic organothallium compounds. The diagonal HF force constants obtained from a Fletcher-Powell geometry optimization are now used for a normal-mode analysis of TlCH{sub 3}, Tl(CH{sub 3}){sub 2}{sup +}, Tl(CH{sub 3}){sub 3}, Tl(CH{sub 3}){sub 2}Br, and Tl(CH{sub 3}){sub 4}{sup {minus}}. In order to calculate frequencies comparable to experimental values, the HF force field has been scaled by using scaling factors obtained from experimental infrared and Raman measurements on Tl(CH{sub 3}){sub 2}{sup +} and TlBr. The vibrational spectra of Tl(CH{sub 3}){sub 2}{sup +} were remeasured (infrared and Raman) in order to obtainmore » an accurate force field. Predictions are made for the vibrational spectrum of the as yet undetected TlCH{sub 3} molecule. Experimental infrared and Raman results for Tl(CH{sub 3}){sub 3} compare reasonably well with our calculated frequencies. Relativistic and correlation effects are analyzed for the vibrational frequencies of Tl(CH{sub 3}){sub 2}{sup +}.« less

  13. Isolation and Selection of Microalgal Strains from Natural Water Sources in Viet Nam with Potential for Edible Oil Production.

    PubMed

    Thao, Tran Yen; Linh, Dinh Thi Nhat; Si, Vo Chi; Carter, Taylor W; Hill, Russell T

    2017-06-23

    Industrial vegetable oil production in Viet Nam depends on oil seeds and crude plant oils that are currently more than 90% imported. As the first step in investigating the feasibility of using microalgae to provide Viet Nam with a domestic source of oil for food and edible oil industries, fifty lipid-producing microalgae were isolated and characterized. The microalgae were isolated from water sources ranging from freshwater to brackish and marine waters from a wide geographic distribution in Viet Nam. Initial analyses showed that 20 of the 50 strains had good growth rates, produced high biomass and had high lipid content, ranging up to 50% of dry weight biomass. 18S rRNA gene sequence analyses of the 50 strains showed a great diversity in this assemblage of microalgae, comprising at least 38 species and representatives of 25 genera : Chlamydomonas , Poterioochromonas , Scenedesmus , Desmodesmus , Chlorella , Bracteacoccus , Monoraphidium , Selenastrum , Acutodesmus , Mychonastes , Ankistrodesmus , Kirchneriella , Raphidocelis , Dictyosphaerium , Coelastrella , Schizochlamydella , Oocystidium , Nannochloris , Auxenochlorella , Chlorosarcinopsis , Stichococcus , Picochlorum , Prasinoderma , Chlorococcum , and Marvania. Some of the species are closely related to well-known lipid producers such as Chlorella sorokiniana , but some other strains are not closely related to the strains found in public sequence databases and likely represent new species. Analysis of oil quality showed that fatty acid profiles of the microalgal strains were very diverse and strain-dependent. Fatty acids in the microalgal oils comprised saturated fatty acids (SFAs), poly-unsaturated fatty acids (PUFAs), and mono-unsaturated fatty acids (MUFAs). The main SFA was palmitic acid. MUFAs and PUFAs were dominated by oleic acid, and linoleic and linolenic acids, respectively. Some strains were especially rich in the essential fatty acid α-linolenic acid (ALA), which comprised more than 20% of the

  14. Isolation and Selection of Microalgal Strains from Natural Water Sources in Viet Nam with Potential for Edible Oil Production

    PubMed Central

    Thao, Tran Yen; Linh, Dinh Thi Nhat; Si, Vo Chi; Carter, Taylor W.; Hill, Russell T.

    2017-01-01

    Industrial vegetable oil production in Viet Nam depends on oil seeds and crude plant oils that are currently more than 90% imported. As the first step in investigating the feasibility of using microalgae to provide Viet Nam with a domestic source of oil for food and edible oil industries, fifty lipid-producing microalgae were isolated and characterized. The microalgae were isolated from water sources ranging from freshwater to brackish and marine waters from a wide geographic distribution in Viet Nam. Initial analyses showed that 20 of the 50 strains had good growth rates, produced high biomass and had high lipid content, ranging up to 50% of dry weight biomass. 18S rRNA gene sequence analyses of the 50 strains showed a great diversity in this assemblage of microalgae, comprising at least 38 species and representatives of 25 genera: Chlamydomonas, Poterioochromonas, Scenedesmus, Desmodesmus, Chlorella, Bracteacoccus, Monoraphidium, Selenastrum, Acutodesmus, Mychonastes, Ankistrodesmus, Kirchneriella, Raphidocelis, Dictyosphaerium, Coelastrella, Schizochlamydella, Oocystidium, Nannochloris, Auxenochlorella, Chlorosarcinopsis, Stichococcus, Picochlorum, Prasinoderma, Chlorococcum, and Marvania. Some of the species are closely related to well-known lipid producers such as Chlorella sorokiniana, but some other strains are not closely related to the strains found in public sequence databases and likely represent new species. Analysis of oil quality showed that fatty acid profiles of the microalgal strains were very diverse and strain-dependent. Fatty acids in the microalgal oils comprised saturated fatty acids (SFAs), poly-unsaturated fatty acids (PUFAs), and mono-unsaturated fatty acids (MUFAs). The main SFA was palmitic acid. MUFAs and PUFAs were dominated by oleic acid, and linoleic and linolenic acids, respectively. Some strains were especially rich in the essential fatty acid α-linolenic acid (ALA), which comprised more than 20% of the fatty acids in these strains

  15. CH-TRU Waste Content Codes

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

    Washington TRU Solutions LLC

    2008-01-16

    The CH-TRU Waste Content Codes (CH-TRUCON) document describes the inventory of the U.S. Department of Energy (DOE) CH-TRU waste within the transportation parameters specified by the Contact-Handled Transuranic Waste Authorized Methods for Payload Control (CH-TRAMPAC). The CH-TRAMPAC defines the allowable payload for the Transuranic Package Transporter-II (TRUPACT-II) and HalfPACT packagings. This document is a catalog of TRUPACT-II and HalfPACT authorized contents and a description of the methods utilized to demonstrate compliance with the CH-TRAMPAC. A summary of currently approved content codes by site is presented in Table 1. The CH-TRAMPAC describes "shipping categories" that are assigned to each payload container.more » Multiple shipping categories may be assigned to a single content code. A summary of approved content codes and corresponding shipping categories is provided in Table 2, which consists of Tables 2A, 2B, and 2C. Table 2A provides a summary of approved content codes and corresponding shipping categories for the "General Case," which reflects the assumption of a 60-day shipping period as described in the CH-TRAMPAC and Appendix 3.4 of the CH-TRU Payload Appendices. For shipments to be completed within an approximately 1,000-mile radius, a shorter shipping period of 20 days is applicable as described in the CH-TRAMPAC and Appendix 3.5 of the CH-TRU Payload Appendices. For shipments to WIPP from Los Alamos National Laboratory (LANL), Nevada Test Site, and Rocky Flats Environmental Technology Site, a 20-day shipping period is applicable. Table 2B provides a summary of approved content codes and corresponding shipping categories for "Close-Proximity Shipments" (20-day shipping period). For shipments implementing the controls specified in the CH-TRAMPAC and Appendix 3.6 of the CH-TRU Payload Appendices, a 10-day shipping period is applicable. Table 2C provides a summary of approved content codes and corresponding shipping categories for "Controlled

  16. Art as a Political Act: Expression of Cultural Identity, Self-Identity, and Gender by Suk Nam Yun and Yong Soon Min

    ERIC Educational Resources Information Center

    Caruso, Hwa Young Choi

    2005-01-01

    This cross-cultural study explored the lives of two contemporary Korean/Korean American women artists--Suk Nam Yun and Yong Soon Min--who live in Seoul, South Korea, and Los Angeles, California. The author's research focused on the artists' identity formation, artistic expression, professional achievements, and the role of art as a political act.…

  17. Trends in Second-Hand Tobacco Smoke Exposure Levels at Home among Viet Nam School Children Aged 13-15 and Associated Factors.

    PubMed

    Lam, Nguyen Tuan; Nga, Pham Thi Quynh; Minh, Hoang Van; Giang, Kim Bao; Hai, Phan Thi; Huyen, Doan Thu; Linh, Nguyen Thuy; Van, Duong Khanh; Khue, Luong Ngoc

    2016-01-01

    Second-hand tobacco smoke (SHS) exposure at home, especially among children, is a serious issue in Viet Nam. During the past decade, much effort has been taken for tobacco control in the country, including various prgorammes aiming to reduce SHS exposure among adults and children. This article analysed trends and factors associated with SHS exposure at home among school children aged 13-15 in Viet Nam, using the Global Youth Tobacco Surveys conducted in 2007 and 2014. Descriptive and inferential statistical methods with logistic regression were applied. Overall, there was a significant reduction in the level of exposure, from 58.5% (95%CI: 57.6-59.3) in 2007 to 47.1% (95%CI: 45.4-48.8) in 2014. Of the associated factors, having one or both parents smoking was significantly associated with the highest odds of SHS exposure at home (OR=5.0; 95%CI: 4.2-6.1). Conversely, having a mother with a college or higher education level was found to be a protective factor (OR=0.5; 95%CI: 0.3-0.8).

  18. Formation of unexpected silicon- and disiloxane-bridged multiferrocenyl derivatives bearing Si-O-CH[double bond, length as m-dash]CH2 and Si-(CH2)2C(CH3)3 substituents via cleavage of tetrahydrofuran and trapping of its ring fragments.

    PubMed

    Bruña, Sonia; González-Vadillo, Ana Mª; Ferrández, Marta; Perles, Josefina; Montero-Campillo, M Merced; Mó, Otilia; Cuadrado, Isabel

    2017-09-12

    The formation of a family of silicon- and siloxane-bridged multiferrocenyl derivatives carrying different functional groups attached to silicon, including Fc 2 (CH 3 ) 3 C(CH 2 ) 2 SiCH[double bond, length as m-dash]CH 2 (5), Fc 2 (CH 2 [double bond, length as m-dash]CH-O)SiCH[double bond, length as m-dash]CH 2 (6), Fc 2 (OH)SiCH[double bond, length as m-dash]CH 2 (7), Fc 2 (CH 2 [double bond, length as m-dash]CH-O)Si-O-Si(O-CH[double bond, length as m-dash]CH 2 )Fc 2 (8) and Fc 2 (CH 2 [double bond, length as m-dash]CH-O)Si-O-SiFc 3 (9) is described. Silyl vinyl ether molecules 6, 8 and 9 and the heteroleptic vinylsilane 5 resulted from the competing metathesis reaction of lithioferrocene (FcLi), CH 2 [double bond, length as m-dash]CH-OLi or (CH 3 ) 3 C(CH 2 ) 2 Li with the corresponding multifunctional chlorosilane, Cl 3 SiCH[double bond, length as m-dash]CH 2 or Cl 3 Si-O-SiCl 3 . The last two organolithium species have been likely formed in situ by fragmentation of the tetrahydrofuran solvent. Diferrocenylvinyloxyvinylsilane 6 is noteworthy since it represents a rare example of a redox-active silyl mononomer in which two different C[double bond, length as m-dash]C polymerisable groups are directly connected to silicon. The molecular structures of the silicon-containing multiferrocenyl species 5, 6, 8 and 9 have been investigated by single-crystal X-ray diffraction studies, demonstrating the capture and storage processes of two ring fragments resulting from the cleavage of cyclic THF in redox-active and stable crystalline organometallic compounds. From electrochemical studies we found that by changing the anion of the supporting electrolyte from [PF 6 ] - to [B(C 6 F 5 ) 4 ] - , the redox behaviour of tetrametallic disiloxane 8 can be switched from a poorly resolved multistep redox process to four consecutive well-separated one-electron oxidations, corresponding to the sequential oxidation of the four ferrocenyl moieties.

  19. Analysis of Global Horizontal Irradiance in Version 3 of the National Solar Radiation Database.

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

    Hansen, Clifford; Martin, Curtis E.; Guay, Nathan Gene

    We report an analysis that compares global horizontal irradiance (GHI) estimates from version 3 of the National Solar Radiation Database (NSRDB v3) with surface measurements of GHI at a wide variety of locations over the period spanning from 2005 to 2012. The NSRDB v3 estimate of GHI are derived from the Physical Solar Model (PSM) which employs physics-based models to estimate GHI from measurements of reflected visible and infrared irradiance collected by Geostationary Operational Environment Satellites (GOES) and several other data sources. Because the ground measurements themselves are uncertain our analysis does not establish the absolute accuracy for PSM GHI.more » However by examining the comparison for trends and for consistency across a large number of sites, we may establish a level of confidence in PSM GHI and identify conditions which indicate opportunities to improve PSM. We focus our evaluation on annual and monthly insolation because these quantities directly relate to prediction of energy production from solar power systems. We find that generally, PSM GHI exhibits a bias towards overestimating insolation, on the order of 5% when all sky conditions are considered, and somewhat less (-3%) when only clear sky conditions are considered. The biases persist across multiple years and are evident at many locations. In our opinion the bias originates with PSM and we view as less credible that the bias stems from calibration drift or soiling of ground instruments. We observe that PSM GHI may significantly underestimate monthly insolation in locations subject to broad snow cover. We found examples of days where PSM GHI apparently misidentified snow cover as clouds, resulting in significant underestimates of GHI during these days and hence leading to substantial understatement of monthly insolation. Analysis of PSM GHI in adjacent pixels shows that the level of agreement between PSM GHI and ground data can vary substantially over distances on the order of 2 km

  20. Genesis of economic relevant fresh groundwater resources in Pleistocene/ Neogene aquifers in Nam Dinh (Red River Delta, Vietnam).

    NASA Astrophysics Data System (ADS)

    Wagner, F.; Ludwig, R. R.; Noell, U.; Hoang, H. V.; Pham, N. Q.; Larsen, F.; Lindenmaier, F.

    2012-04-01

    In the Southern Red River Delta (Nam Dinh Province, Vietnam), a local lens of low saline pore water of high quality has been identified in unconsolidated Pleistocene and Neogene aquifers, which are regionally known to contain brackish and saline pore waters. Since the 1990ies, ongoing overexploitation of the fresh groundwater results in decreasing GW heads up to 0.6 m/a and the development of a regional abstraction cone. The presented study focuses on distribution and genesis of fresh and saline pore waters and reflects the results in frame of the regional hydrogeological context. Observations of the geological structure and groundwater dynamics combined with hydrochemical and isotopic studies suggest adjacent Triassic hard rock aquifers as the major source for fresh Pleistocene and Neogene groundwater. Salinization status in the economically most relevant Pleistocene aquifer has been studied based on archive and new hydrochemical and geophysical data. Own hydrochemical field studies as well as laboratory measurements of the specific resistivity of dry sediment samples allow the translation of induction logging data from existing monitoring wells into vertical pore water salinity profiles. This approach suggests the regional occurrence of saline pore water in shallow Holocene sediments in the working area, as confirmed by pore water studies in Hoan et al. (2010). Interpretation of induction logging and stable isotope data suggest vertical diffusion of saline pore water in shallow Holocene sediments as a source for high saline pore water in deeper aquifers. Analytical diffusion modeling for a period of 3000 years confirms that vertical diffusion of Holocene paleo-sea water can explain saline pore water in Pleistocene and Neogene aquifers in a stagnant environment. The constant influx of fresh groundwater from adjacent Triassic hard rocks results in flushing of the primary Pleistocene and Neogene pore water and inhibits the infiltration of saline water from marine

  1. Gauging the Acceptability of HIV Vaccines: An Exploratory Study Examining Knowledge, Attitudes, and Beliefs among Injecting Drug Users in Viet Nam

    ERIC Educational Resources Information Center

    Nguyen, France

    2007-01-01

    In contrast to other countries in Southeast Asia, the HIV/ AIDS epidemic is in the initial stages in Viet Nam, although the rates have increased notably since 1997. This study examined attitudes towards the use of an HIV vaccine (when one becomes available) as a means for preventing the disease. Since injecting drug users are the great majority of…

  2. Direct observation of unimolecular decay of CH 3 CH 2 CHOO Criegee intermediates to OH radical products

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

    Fang, Yi; Liu, Fang; Klippenstein, Stephen J.

    2016-07-28

    The unimolecular decay of carbonyl oxide intermediates, known as Criegee intermediates, produced in alkene ozonolysis is a significant source of OH radicals in the troposphere. Here, the rate of appearance of OH radical products is examined directly in the time-domain for a prototypical alkyl-substituted Criegee intermediate, CH3CH2CHOO, following vibrational activation under collision-free conditions. Complementary statistical Rice-Ramsperger-Kassel-Marcus calculations of the microcanonical unimolecular decay rate for CH3CH2CHOO are also carried out at energies in the vicinity of the barrier for 1,4 hydrogen atom transfer that leads to OH products. Tunneling through the barrier, derived from high level electronic structure calculations, contributes significantlymore » to the decay rate. Infrared transitions of CH3CH2CHOO are identified in the CH stretch overtone region, which are detected by ultraviolet laser-induced fluorescence of the resultant OH products. The features observed are attributed to CH vibrational excitations and conformational forms utilizing insights from theory. Both experiment and theory yield unimolecular decay rates for CH3CH2CHOO of ca. 10(7) s(-1), which are slower than those obtained for syn-CH3CHOO or (CH3)(2)COO reported previously [Fang et al., J. Chem. Phys. 144, 061102 (2016)] at similar energies. Master equation modeling is also utilized to predict the thermal decay rate of CH3CH2CHOO under atmospheric conditions, giving a rate of 279 s(-1) at 298 K.« less

  3. Completeness and reliability of mortality data in Viet Nam: Implications for the national routine health management information system

    PubMed Central

    Phuong Hoa, Nguyen; Walker, Sue M.; Hill, Peter S.; Rao, Chalapati

    2018-01-01

    Background Mortality statistics form a crucial component of national Health Management Information Systems (HMIS). However, there are limitations in the availability and quality of mortality data at national level in Viet Nam. This study assessed the completeness of recorded deaths and the reliability of recorded causes of death (COD) in the A6 death registers in the national routine HMIS in Viet Nam. Methodology and findings 1477 identified deaths in 2014 were reviewed in two provinces. A capture-recapture method was applied to assess the completeness of the A6 death registers. 1365 household verbal autopsy (VA) interviews were successfully conducted, and these were reviewed by physicians who assigned multiple and underlying cause of death (UCOD). These UCODs from VA were then compared with the CODs recorded in the A6 death registers, using kappa scores to assess the reliability of the A6 death register diagnoses. The overall completeness of the A6 death registers in the two provinces was 89.3% (95%CI: 87.8–90.8). No COD recorded in the A6 death registers demonstrated good reliability. There is very low reliability in recording of cardiovascular deaths (kappa for stroke = 0.47 and kappa for ischaemic heart diseases = 0.42) and diabetes (kappa = 0.33). The reporting of deaths due to road traffic accidents, HIV and some cancers are at a moderate level of reliability with kappa scores ranging between 0.57–0.69 (p<0.01). VA methods identify more specific COD than the A6 death registers, and also allow identification of multiple CODs. Conclusions The study results suggest that data completeness in HMIS A6 death registers in the study sample of communes was relatively high (nearly 90%), but triangulation with death records from other sources would improve the completeness of this system. Further, there is an urgent need to enhance the reliability of COD recorded in the A6 death registers, for which VA methods could be effective. Focussed consultation among

  4. Completeness and reliability of mortality data in Viet Nam: Implications for the national routine health management information system.

    PubMed

    Hong, Tran Thi; Phuong Hoa, Nguyen; Walker, Sue M; Hill, Peter S; Rao, Chalapati

    2018-01-01

    Mortality statistics form a crucial component of national Health Management Information Systems (HMIS). However, there are limitations in the availability and quality of mortality data at national level in Viet Nam. This study assessed the completeness of recorded deaths and the reliability of recorded causes of death (COD) in the A6 death registers in the national routine HMIS in Viet Nam. 1477 identified deaths in 2014 were reviewed in two provinces. A capture-recapture method was applied to assess the completeness of the A6 death registers. 1365 household verbal autopsy (VA) interviews were successfully conducted, and these were reviewed by physicians who assigned multiple and underlying cause of death (UCOD). These UCODs from VA were then compared with the CODs recorded in the A6 death registers, using kappa scores to assess the reliability of the A6 death register diagnoses. The overall completeness of the A6 death registers in the two provinces was 89.3% (95%CI: 87.8-90.8). No COD recorded in the A6 death registers demonstrated good reliability. There is very low reliability in recording of cardiovascular deaths (kappa for stroke = 0.47 and kappa for ischaemic heart diseases = 0.42) and diabetes (kappa = 0.33). The reporting of deaths due to road traffic accidents, HIV and some cancers are at a moderate level of reliability with kappa scores ranging between 0.57-0.69 (p<0.01). VA methods identify more specific COD than the A6 death registers, and also allow identification of multiple CODs. The study results suggest that data completeness in HMIS A6 death registers in the study sample of communes was relatively high (nearly 90%), but triangulation with death records from other sources would improve the completeness of this system. Further, there is an urgent need to enhance the reliability of COD recorded in the A6 death registers, for which VA methods could be effective. Focussed consultation among stakeholders is needed to develop a suitable mechanism and

  5. Nuclear Hyperfine Structure in the Donor – Acceptor Complexes (CH3)3N-BF3 and (CH)33N-B(CH3)3

    EPA Science Inventory

    The donor-acceptor complexes (CH3)3N-BF3 and (CH3)3N-B(CH3)3 have been reinvestigated at high resolution by rotational spectroscopy in a supersonic jet. Nuclear hyperfine structure resulting from both nitrogen and boron has been resolved and quadrupole coupling constants have bee...

  6. Prevalence and Risk Factors for Tuberculosis Infection among Hospital Workers in Hanoi, Viet Nam

    PubMed Central

    Kobayashi, Nobuyuki; Yanai, Hideki; Toyota, Emiko; Sakurada, Shinsaku; Huu Thuong, Pham; Cuong, Vu Cao; Nanri, Akiko; Mizoue, Tetsuya; Matsushita, Ikumi; Harada, Nobuyuki; Higuchi, Kazue; Tuan, Le Anh; Keicho, Naoto

    2009-01-01

    Background Transmission of tuberculosis (TB) to health care workers (HCWs) is a global issue. Although effective infection control measures are expected to reduce nosocomial TB, HCWs' infection has not been assessed enough in TB high burden countries. We conducted a cross-sectional study to determine the prevalence of TB infection and its risk factors among HCWs in Hanoi, Viet Nam. Methodology/Principal Findings A total of 300 HCWs including all staff members in a municipal TB referral hospital received an interferon-gamma release assay (IGRA), QuantiFERON-TB Gold In-TubeTM, followed by one- and two-step tuberculin skin test (TST) and a questionnaire-based interview. Agreement between the tests was evaluated by kappa statistics. Risk factors for TB infection were analyzed using a logistic regression model. Among the participants aged from 20 to 58 years (median = 40), prevalence of TB infection estimated by IGRA, one- and two-step TST was 47.3%, 61.1% and 66.3% respectively. Although the levels of overall agreement between IGRA and TST were moderate, the degree of agreement was low in the group with BCG history (kappa = 0.29). Working in TB hospital was associated with twofold increase in odds of TB infection estimated by IGRA. Increased age, low educational level and the high body mass index also demonstrated high odds ratios of IGRA positivity. Conclusions/Significance Prevalence of TB infection estimated by either IGRA or TST is high among HCWs in the hospital environment for TB care in Viet Nam and an infection control program should be reinforced. In communities with heterogeneous history of BCG vaccination, IGRA seems to estimate TB infection more accurately than any other criteria using TST. PMID:19710920

  7. Psychological and Social Factors Associated with Late Pregnancy Iron Deficiency Anaemia in Rural Viet Nam: A Population-Based Prospective Study

    PubMed Central

    Tran, Thach Duc; Biggs, Beverley-Ann; Tran, Tuan; Casey, Gerard J.; Hanieh, Sarah; Simpson, Julie Anne; Dwyer, Terence; Fisher, Jane

    2013-01-01

    Objectives The aim of this study was to examine the relationships between psychological and social factors and late pregnancy IDA among pregnant women in rural Viet Nam. Methods Pregnant women from 50 randomly-selected communes within Ha Nam province were recruited and assessed at 12 - 20 weeks gestation (Wave 1, W1). They were followed up in the last trimester (Wave 2, W2). IDA was defined as Haemoglobin < 11 g/dL and serum ferritin < 15 ng/mL. Symptoms of Common Mental Disorders (CMD) were assessed by the Edinburgh Postnatal Depression Scale-Vietnam (EPDS-V). Persistent antenatal CMD was defined as having an EPDS-V score ≥ 4 in both W1 and W2. Hypothesis models were tested by Structural Equation Modeling analyses. Results A total of 378 women provided complete data at both W1 and W2. The incidence risk of IDA in the third trimester was 13.2% (95% confidence interval (CI): 9.8-16.7). Persistent CMD was found in 16.9% (95% CI: 13.1-20.7) pregnant women and predicted by intimate partner violence, fear of other family members, experience of childhood abuse, coincidental life adversity, and having a preference for the sex of the baby. There was a significant pathway from persistent CMD to IDA in late pregnancy via the length of time that iron supplements had been taken. Receiving advice to take iron supplements and higher household wealth index were indirectly related to lower risk of late pregnancy IDA. Early pregnancy IDA and being multi-parous also contributed to late pregnancy IDA. Conclusions Antenatal IDA and CMD are prevalent public health problems among women in Viet Nam. The link between them suggests that while direct recommendations to use iron supplements are important, the social factors associated with common mental disorders should be addressed in antenatal care in order to improve the health of pregnant women and their infants. PMID:24167605

  8. Psychological and social factors associated with late pregnancy iron deficiency anaemia in rural Viet Nam: a population-based prospective study.

    PubMed

    Tran, Thach Duc; Biggs, Beverley-Ann; Tran, Tuan; Casey, Gerard J; Hanieh, Sarah; Simpson, Julie Anne; Dwyer, Terence; Fisher, Jane

    2013-01-01

    The aim of this study was to examine the relationships between psychological and social factors and late pregnancy IDA among pregnant women in rural Viet Nam. Pregnant women from 50 randomly-selected communes within Ha Nam province were recruited and assessed at 12 - 20 weeks gestation (Wave 1, W1). They were followed up in the last trimester (Wave 2, W2). IDA was defined as Haemoglobin < 11 g/dL and serum ferritin < 15 ng/mL. Symptoms of Common Mental Disorders (CMD) were assessed by the Edinburgh Postnatal Depression Scale-Vietnam (EPDS-V). Persistent antenatal CMD was defined as having an EPDS-V score ≥ 4 in both W1 and W2. Hypothesis models were tested by Structural Equation Modeling analyses. A total of 378 women provided complete data at both W1 and W2. The incidence risk of IDA in the third trimester was 13.2% (95% confidence interval (CI): 9.8-16.7). Persistent CMD was found in 16.9% (95% CI: 13.1-20.7) pregnant women and predicted by intimate partner violence, fear of other family members, experience of childhood abuse, coincidental life adversity, and having a preference for the sex of the baby. There was a significant pathway from persistent CMD to IDA in late pregnancy via the length of time that iron supplements had been taken. Receiving advice to take iron supplements and higher household wealth index were indirectly related to lower risk of late pregnancy IDA. Early pregnancy IDA and being multi-parous also contributed to late pregnancy IDA. Antenatal IDA and CMD are prevalent public health problems among women in Viet Nam. The link between them suggests that while direct recommendations to use iron supplements are important, the social factors associated with common mental disorders should be addressed in antenatal care in order to improve the health of pregnant women and their infants.

  9. The online measured black carbon aerosol and source orientations in the Nam Co region, Tibet.

    PubMed

    Zhang, Xin; Ming, Jing; Li, Zhongqin; Wang, Feiteng; Zhang, Guoshuai

    2017-11-01

    Equivalent black carbon (eBC) mass concentrations were measured by an aethalometer (AE-31) in the Nam Co, central Tibet from 2010 to 2014. Different from previous filter-sampling studies (Ming et al., J Environ Sci 22(11):1748-1756, 2010; Zhao et al., Environ Sci Pollut Res 20:5827-5838, 2013), the first high-resolution online eBC measurement conducted in central Tibet is reported here, allowing to discuss the diurnal variations as well as seasonal variabilities of eBC. Average daily eBC concentration was 74 ± 50 ng/m 3 , reflecting a global background level. Meteorological conditions influenced eBC concentrations largely at seasonal scale, which are higher in February-May but lower in June-January. The highest eBC concentrations (greater than 210 ng/m 3 ) were more associated with the W and WSW winds smaller than 6 m/s. The diurnal variations of eBC showed plateaus from 10:00 to 15:00 with seasonal variations, associated with local anthropogenic activities, such as indigenous Tibetan burning animal waste and tourism traffic. The PBLHs showed a co-variance with eBC concentrations, implicating close sources. The aerosol optical depths derived from the MODIS data over the Nam Co Observatory Station (NCOS)-included sub-area (30° N-40° N, 90° E-100° E) showed significant relationship with eBC concentrations. This suggests that nearby or short-distance sources other than long-distance transported pollutants could be important contributors to eBC concentrations at the NCOS, different from the conclusions suggested by previous studies.

  10. Impact of mandatory motorcycle helmet wearing legislation on head injuries in Viet Nam: results of a preliminary analysis.

    PubMed

    Passmore, Jonathon; Tu, Nguyen Thi Hong; Luong, Mai Anh; Chinh, Nguyen Duc; Nam, Nguyen Phuong

    2010-04-01

    To compare estimated prevalence of head injuries among road traffic injury patients admitted to hospitals, before and after the introduction of a mandatory helmet law in the Socialist Republic of Viet Nam. Before and after study of all road traffic injury patients with head injuries admitted to 20 provincial and central hospitals 3 months before and after the new law came into effect on 15 December 2007. Relative risk was computed and comparison made for the periods of 3 months before and after the new law. The study found a 16 percent reduction in the risk of road traffic head injuries (4683 to 3522; relative risk [RR] 0.84; 95% confidence interval [CI] 0.81-0.87) and an 18 percent reduction in the risk of road traffic death (deaths in hospital plus injured patients discharged to die at home; 566 to 417; RR 0.82; 95% CI 0.73-0.93). Over the first 3 months of the comprehensive mandatory helmet legislation there has been a significant reduction in the risk of road traffic head injuries among patients admitted to 20 hospitals. The Viet Nam Government's decision to require all motorcycle riders and passengers to wear helmets is suspected of leading to positive road safety benefits and should be seen as a policy example for other low- and middle-income countries with a high utilization of motorcycles for transport.

  11. Allergen sensitisation among chronic respiratory diseases in urban and rural areas of the south of Viet Nam.

    PubMed

    Chu, H T; Godin, I; Phuong, N T; Nguyen, L H; Hiep, T T M; Michel, O

    2018-02-01

    To evaluate the prevalence of and risk factors for allergen sensitisation among patients with chronic respiratory disease (CRD) in southern Viet Nam. An environmental questionnaire and skin prick tests for airborne and food allergens were administered to patients with CRD, defined as individuals with respiratory symptoms and lung function defects. Of 610 CRD patients, 56% had chronic obstructive pulmonary disease and 31% were asthma patients; 80% were males. The most frequent sensitisers were dust mites (Dermatophagoides farinae 22%, Blomia tropicalis 19%, D. pteronyssinus 18%) and cockroach droppings (13%). Among study participants, 37% were from rural settings and 36% from urban areas, whereas 27% had migrated from rural to urban areas. Compared with people from rural areas, being born in an urban area was a risk factor for sensitisation to mites (OR 1.56, 95%CI 1.11-2.20, P < 0.02). In multivariate analysis, place of birth remained a risk factor for mite sensitisation. Compared with the native urban population, the risk of mite sensitisation was not significantly different among patients born in rural areas and those migrating to urban areas. Dust mites and cockroach droppings were the most frequent allergens among people with CRD in the south of Viet Nam. Compared with the urban population, being native to a rural area was protective against mite sensitisation, but this effect ceased to be significant after migration from rural to urban areas.

  12. ChIP-chip versus ChIP-seq: Lessons for experimental design and data analysis

    PubMed Central

    2011-01-01

    Background Chromatin immunoprecipitation (ChIP) followed by microarray hybridization (ChIP-chip) or high-throughput sequencing (ChIP-seq) allows genome-wide discovery of protein-DNA interactions such as transcription factor bindings and histone modifications. Previous reports only compared a small number of profiles, and little has been done to compare histone modification profiles generated by the two technologies or to assess the impact of input DNA libraries in ChIP-seq analysis. Here, we performed a systematic analysis of a modENCODE dataset consisting of 31 pairs of ChIP-chip/ChIP-seq profiles of the coactivator CBP, RNA polymerase II (RNA PolII), and six histone modifications across four developmental stages of Drosophila melanogaster. Results Both technologies produce highly reproducible profiles within each platform, ChIP-seq generally produces profiles with a better signal-to-noise ratio, and allows detection of more peaks and narrower peaks. The set of peaks identified by the two technologies can be significantly different, but the extent to which they differ varies depending on the factor and the analysis algorithm. Importantly, we found that there is a significant variation among multiple sequencing profiles of input DNA libraries and that this variation most likely arises from both differences in experimental condition and sequencing depth. We further show that using an inappropriate input DNA profile can impact the average signal profiles around genomic features and peak calling results, highlighting the importance of having high quality input DNA data for normalization in ChIP-seq analysis. Conclusions Our findings highlight the biases present in each of the platforms, show the variability that can arise from both technology and analysis methods, and emphasize the importance of obtaining high quality and deeply sequenced input DNA libraries for ChIP-seq analysis. PMID:21356108

  13. Resolved 12CH2D2 and 13CH3D in CH4 as Sensitive Indicators of Disequilibrium and Equilibrium during Microbial Methane Cycling

    NASA Astrophysics Data System (ADS)

    Ash, J. L.; Egger, M.; Slomp, C. P.; Kohl, I. E.; Treude, T.; Rumble, D.; Young, E. D.

    2016-12-01

    The ability to measure the relative concentrations of at least two doubly-substituted rare isotopologues of gases with biogeochemical relevance provides new constraints on sources and sinks of these gases. In particular, as shown recently for O2, the use of two independent, rare isotopologues allows for detection of thermodynamic intra-species equilibrium and disequilibrium. Here, we report the first measurements of fully resolved 13CH3D and 12CH2D2 from natural samples of microbial methane gas. A suite of sedimentary methane samples from the Bornholm Basin in the Baltic Sea was collected during IODP Exp. 347. Sample depths range from 2-20 meters below seafloor (mbsf). Methane concentrations decrease with depth, and mcrA (a marker for methanogenesis and methanotropy) is present throughout. See Figure. Both Δ13CH3D and Δ12CH2D2 increase with depth as methane concentrations decrease with the shallowest samples exhibiting disequilibrium by up to 2‰ in Δ13CH3D and 13‰ in Δ12CH2D2 while the deepest samples approach isotopic thermodynamic equilibrium (marked by grey bars in Figure). The Fe-mediated anaerobic oxidation of methane (Fe-AOM) has been inferred in these sediments by geochemical modeling . Slow methane cycling by methanogensis and methanotrophy is likely responsible for the approach to isotopic bond order equilibrium in CH4 with depth, consistent with Fe-AOM. While axenic culturing experiments generate methane with large deficits in 12CH2D2 (reported at this meeting), these data from the Baltic Sea demonstrate that isotopic equilibrium can be achieved during microbial recycling of methane. In the absence of Δ12CH2D2, the Δ13CH3D values alone could be misinterpreted as representing gradients in temperature due perhaps to exothermic organic matter degradation. The combination of both mass-18 rare isotopologues of methane provides the means to distinguish equilibrium from disequilibrium and probe microbial methane cycling even where Δ13CH3D suggests

  14. Diminished CAGE Effect in {p}-H2: Infrared Spectra of CH3S Observed from Photolysis of CH3SH, CH3SCH3, and CH3SSCH3 Isolated in {p}-H2

    NASA Astrophysics Data System (ADS)

    Lee, Yuan-Pern; Bahou, Mohammed

    2010-06-01

    We report infrared absorption spectrum of the methylthio (or thiomethoxy) radical, CH3S, isolated in solid {p}-H2. CH3S was produced by in situ UV photodissociation of three precursors: CH3SH, CH3SH3, and CH3SSCH3 isolated in solid {p}-H2. New absorption features commonly observed with similar intensity ratios in experiments using these precursors are assigned as absorption of CH3S. In Addition to the previously assigned transitions of ν 3 (a1) at 727.1 cm-1, fundamental transitions ν 6 (a1) at 771.1, ν 6 (e) at 1056.6, ν 5 (a1) at 1400.0, and &nu 4 (a1) at 2898.0 cm-1 were observed. The wavenumbers of these features agree satisfactorily with those predicted with a spin-vibronic Hamiltonian accounting for the anharmonic effects and the Jahn-Teller effects to the qu rtic term; the corresponding wavenumbers predicted from theory are ν 6 (a1) at 793, ν 6 (e) at 1105, ν 5 (a1) at 1436, and ν 4 (a1) at 2938 cm-1, with deviations of 14-4.6 % from experiments. Previous attempts of UV photolysis of CH3SCH3 and CH3SSCH3 isolated in an Ar matrix failed to produce CH3S. These results serve as an excellent example that the diminished cae effect of solid {p}-H2 makes production of free radicals via photolysis in situ feasible. If time permits, other examples will be discussed. A. V. Marenich and J. E. Boggs, J. Chem. Theory Comput., 1, 1162 (2005).

  15. Effects of Boreal Lake Wetlands on Atmospheric 13CH3D and 12CH2D2

    NASA Astrophysics Data System (ADS)

    Haghnegahdar, M. A.; Kohl, I. E.; Schauble, E. A.; Walter Anthony, K. M.; Young, E. D.

    2017-12-01

    Recently, we developed a theoretical model to investigate the potential use of 13CH3D and 12CH2D2 as tools for tracking atmospheric methane budget. We used electronic structure methods to estimate kinetic isotope fractionations associated with the major sink reactions of CH4 in air (reactions with •OH and Cl•), and literature data with reconnaissance measurements of the relative abundances of 13CH3D and 12CH2D2 to estimate the compositions of the largest atmospheric sources. Here we present new methane rare isotopologue data from boreal wetlands, comprising one of the most important sources, in order to evaluate the robustness of the model. Boreal wetlands (>55° N) account for more than half of the wetland area in the Northern hemisphere. We analyzed methane samples from high latitude lakes representing different geographical regions, geological and ecological contexts, methane fluxes, and isotopic signatures. Using clumped isotopes of CH4 we are able to determine the likely production mechanism for natural CH4 samples. So far, all of our analyzed samples except one plot in the microbial pure-culture methanogenesis field (Young et al. 2017) with ranges of -0.2‰ to +1.2‰ for Δ13CH3D, and -29.6‰ to -18.2‰ for Δ12CH2D2. These compositions are far from equilibrium. The one exception, from Lake Doughnut, Alaska, exhibits Δ13CH3D and Δ12CH2D2 values of +5.2‰ and +18.7‰, respectively, which fall near ambient thermodynamic equilibrium values. This may be an effect of methanotrophy. Mean Δ13CH3D and Δ12CH2D2 for all lake samples are +1.7‰ and -15.4‰ respectively, compared to our original estimate of +6.1‰ and +21.2‰ for the wetland methane source based on an assumption of equilibrium. If we assume that these samples are representative of the overall wetland source, Δ13CH3D decreases by 0.8‰ and Δ12CH2D2 decreases by 0.6‰ in our model of bulk atmospheric methane. Δ13CH3D and Δ12CH2D2 values of air (including •OH and Cl• sink

  16. ChIPWig: a random access-enabling lossless and lossy compression method for ChIP-seq data.

    PubMed

    Ravanmehr, Vida; Kim, Minji; Wang, Zhiying; Milenkovic, Olgica

    2018-03-15

    Chromatin immunoprecipitation sequencing (ChIP-seq) experiments are inexpensive and time-efficient, and result in massive datasets that introduce significant storage and maintenance challenges. To address the resulting Big Data problems, we propose a lossless and lossy compression framework specifically designed for ChIP-seq Wig data, termed ChIPWig. ChIPWig enables random access, summary statistics lookups and it is based on the asymptotic theory of optimal point density design for nonuniform quantizers. We tested the ChIPWig compressor on 10 ChIP-seq datasets generated by the ENCODE consortium. On average, lossless ChIPWig reduced the file sizes to merely 6% of the original, and offered 6-fold compression rate improvement compared to bigWig. The lossy feature further reduced file sizes 2-fold compared to the lossless mode, with little or no effects on peak calling and motif discovery using specialized NarrowPeaks methods. The compression and decompression speed rates are of the order of 0.2 sec/MB using general purpose computers. The source code and binaries are freely available for download at https://github.com/vidarmehr/ChIPWig-v2, implemented in C ++. milenkov@illinois.edu. Supplementary data are available at Bioinformatics online.

  17. Brief behavioural surveys in routine HIV sentinel surveillance: a new tool for monitoring the HIV epidemic in Viet Nam.

    PubMed

    Thanh, Duong Cong; Hien, Nguyen Tran; Tuan, Nguyen Anh; Ha, Hoang Thi Thanh; Thang, Pham Hong; Ha, Nguyen Thi Thanh; Tuan, Le Anh; Quang, Tran Dai; Tram, Tran Hong; Le Hai, Nguyen; Huong, Phan Thi Thu; Son, Vo Hai; Duc, Bui Hoang; Nga, Nguyen Thien; Jacka, David; Sabin, Keith

    2015-01-01

    In this report we describe a new approach in HIV sentinel surveillance that was piloted in Viet Nam in 2009 and is currently being rolled out in all provinces. It comprises a brief behavioural questionnaire added to the HIV sentinel surveillance surveys conducted routinely among people who inject drugs, female sex workers and men who have sex with men. Timely reporting of data from this system has resulted in improvements to HIV prevention efforts for most at-risk populations.

  18. Spatial estimation of sub-hour Global Horizontal Irradiance based on official observations and remote sensors.

    PubMed

    Gutierrez-Corea, Federico-Vladimir; Manso-Callejo, Miguel-Angel; Moreno-Regidor, María-Pilar; Velasco-Gómez, Jesús

    2014-04-11

    This study was motivated by the need to improve densification of Global Horizontal Irradiance (GHI) observations, increasing the number of surface weather stations that observe it, using sensors with a sub-hour periodicity and examining the methods of spatial GHI estimation (by interpolation) with that periodicity in other locations. The aim of the present research project is to analyze the goodness of 15-minute GHI spatial estimations for five methods in the territory of Spain (three geo-statistical interpolation methods, one deterministic method and the HelioSat2 method, which is based on satellite images). The research concludes that, when the work area has adequate station density, the best method for estimating GHI every 15 min is Regression Kriging interpolation using GHI estimated from satellite images as one of the input variables. On the contrary, when station density is low, the best method is estimating GHI directly from satellite images. A comparison between the GHI observed by volunteer stations and the estimation model applied concludes that 67% of the volunteer stations analyzed present values within the margin of error (average of ±2 standard deviations).

  19. Spatial Estimation of Sub-Hour Global Horizontal Irradiance Based on Official Observations and Remote Sensors

    PubMed Central

    Gutierrez-Corea, Federico-Vladimir; Manso-Callejo, Miguel-Angel; Moreno-Regidor, María-Pilar; Velasco-Gómez, Jesús

    2014-01-01

    This study was motivated by the need to improve densification of Global Horizontal Irradiance (GHI) observations, increasing the number of surface weather stations that observe it, using sensors with a sub-hour periodicity and examining the methods of spatial GHI estimation (by interpolation) with that periodicity in other locations. The aim of the present research project is to analyze the goodness of 15-minute GHI spatial estimations for five methods in the territory of Spain (three geo-statistical interpolation methods, one deterministic method and the HelioSat2 method, which is based on satellite images). The research concludes that, when the work area has adequate station density, the best method for estimating GHI every 15 min is Regression Kriging interpolation using GHI estimated from satellite images as one of the input variables. On the contrary, when station density is low, the best method is estimating GHI directly from satellite images. A comparison between the GHI observed by volunteer stations and the estimation model applied concludes that 67% of the volunteer stations analyzed present values within the margin of error (average of ±2 standard deviations). PMID:24732102

  20. Martian CH(4): sources, flux, and detection.

    PubMed

    Onstott, T C; McGown, D; Kessler, J; Lollar, B Sherwood; Lehmann, K K; Clifford, S M

    2006-04-01

    Recent observations have detected trace amounts of CH(4) heterogeneously distributed in the martian atmosphere, which indicated a subsurface CH(4) flux of ~2 x 10(5) to 2 x 10(9) cm(2) s(1). Four different origins for this CH(4) were considered: (1) volcanogenic; (2) sublimation of hydrate- rich ice; (3) diffusive transport through hydrate-saturated cryosphere; and (4) microbial CH(4) generation above the cryosphere. A diffusive flux model of the martian crust for He, H(2), and CH(4) was developed based upon measurements of deep fracture water samples from South Africa. This model distinguishes between abiogenic and microbial CH(4) sources based upon their isotopic composition, and couples microbial CH(4) production to H(2) generation by H(2)O radiolysis. For a He flux of approximately 10(5) cm(2) s(1) this model yields an abiogenic CH(4) flux and a microbial CH(4) flux of approximately 10(6) and approximately 10(9) cm(2) s(1), respectively. This flux will only reach the martian surface if CH(4) hydrate is saturated in the cryosphere; otherwise it will be captured within the cryosphere. The sublimation of a hydrate-rich cryosphere could generate the observed CH(4) flux, whereas microbial CH(4) production in a hypersaline environment above the hydrate stability zone only seems capable of supplying approximately 10(5) cm(2) s(1) of CH(4). The model predicts that He/H(2)/CH(4)/C(2)H(6) abundances and the C and H isotopic values of CH(4) and the C isotopic composition of C(2)H(6) could reveal the different sources. Cavity ring-down spectrometers represent the instrument type that would be most capable of performing the C and H measurements of CH(4) on near future rover missions and pinpointing the cause and source of the CH(4) emissions.

  1. Synthesis, microsome-mediated metabolism, and identification of major metabolites of environmental pollutant naphtho[8,1,2-ghi]chrysene.

    PubMed

    Sharma, Arun K; Gowdahalli, Krishnegowda; Gimbor, Melissa; Amin, Shantu

    2008-05-01

    Naphtho[8,1,2- ghi]chrysene, commonly known as naphtho[1,2- e]pyrene (N[1,2- e]P) is a widespread environmental pollutant, identified in coal tar extract, air borne particulate matter, marine sediment, cigarette smoke condensate, and vehicle exhaust. Herein, we determined the ability of rat liver microsomes to metabolize N[1,2- e]P and an unequivocal assignment of the metabolites by comparing them with independently synthesized standards. We developed the synthesis of both the fjord region and the K-region dihydrodiols and various phenolic derivatives for metabolite identification. The 12-OH-N[1,2- e]P, fjord region dihydrodiol 14 and diol epoxide 15 were synthesized using a Suzuki cross-coupling reaction followed by the appropriate manipulation of the functional groups. The K-region trans-4,5-dihydrodiol ( 18) was prepared by the treatment of N[1,2- e]P with OsO 4 to give cis-dihydrodiol 16, followed by pyridinium chlorochromate oxidation to quinone 17, and finally reduction with NaBH 4 to afford the dihydrodiol 18 with the desired trans stereochemistry. The 9-OH-N[1,2- e]P ( 30) and N[1,2- e]P trans-9,10-dihydrodiol ( 32) were also synthesized following a Suzuki cross-coupling approach starting from 1,2,3,6,7,8-hexahydropyrene-4-boronic acid. The metabolism of N[1,2- e]P with rat liver microsomes led to several dihydrodiol and phenolic metabolites as assessed by the HPLC trace. The 11,12-dihydrodiol and 4,5-dihydrodiol were identified as major dihydrodiol metabolites. The synthesized 9,10-dihydrodiol, on the other hand, did not match with any of the peaks in the metabolism trace. Among the phenols, only 12-OH-N[1,2- e]P was identified in the metabolism. The other phenolic derivatives synthesized, that is, the 4-/5-, 9-, 10-, and 11-hydroxy derivatives, were not detected in the metabolism trace. In summary, N[1,2- e]P trans-11,12-dihydrodiol was the major metabolite formed along with N[1,2- e]P 4,5- trans-dihydrodiol and 12-OH-N[1,2- e]P on exposure of rat liver

  2. Contrast between the mechanisms for dissociative electron attachment to CH3SCN and CH3NCS.

    PubMed

    Miller, Thomas M; Viggiano, Albert A; Shuman, Nicholas S

    2018-05-14

    The kinetics of thermal electron attachment to methyl thiocyanate (CH 3 SCN), methyl isothiocyanate (CH 3 NCS), and ethyl thiocyanate (C 2 H 5 SCN) were measured using flowing afterglow-Langmuir probe apparatuses at temperatures between 300 and 1000 K. CH 3 SCN and C 2 H 5 SCN undergo inefficient dissociative attachment to yield primarily SCN - at 300 K (k = 2 × 10 -10 cm 3 s -1 ), with increasing efficiency as temperature increases. The increase is well described by activation energies of 0.17 eV (CH 3 SCN) and 0.14 eV (C 2 H 5 SCN). CN - product is formed at <1% branching at 300 K, increasing to ∼30% branching at 1000 K. Attachment to CH 3 NCS yields exclusively SCN - ionic product but at a rate at 300 K that is below our detection threshold (k < 10 -12 cm 3 s -1 ). The rate coefficient increases rapidly with increasing temperature (k = 6 × 10 -11 cm 3 s -1 at 600 K), in a manner well described by an activation energy of 0.51 eV. Calculations at the B3LYP/def2-TZVPPD level suggest that attachment to CH 3 SCN proceeds through a dissociative state of CH 3 SCN - , while attachment to CH 3 NCS initially forms a weakly bound transient anion CH 3 NCS -* that isomerizes over an energetic barrier to yield SCN - . Kinetic modeling of the two systems is performed in an attempt to identify a kinetic signature differentiating the two mechanisms. The kinetic modeling reproduces the CH 3 NCS data only if dissociation through the transient anion is considered.

  3. Contrast between the mechanisms for dissociative electron attachment to CH3SCN and CH3NCS

    NASA Astrophysics Data System (ADS)

    Miller, Thomas M.; Viggiano, Albert A.; Shuman, Nicholas S.

    2018-05-01

    The kinetics of thermal electron attachment to methyl thiocyanate (CH3SCN), methyl isothiocyanate (CH3NCS), and ethyl thiocyanate (C2H5SCN) were measured using flowing afterglow-Langmuir probe apparatuses at temperatures between 300 and 1000 K. CH3SCN and C2H5SCN undergo inefficient dissociative attachment to yield primarily SCN- at 300 K (k = 2 × 10-10 cm3 s-1), with increasing efficiency as temperature increases. The increase is well described by activation energies of 0.17 eV (CH3SCN) and 0.14 eV (C2H5SCN). CN- product is formed at <1% branching at 300 K, increasing to ˜30% branching at 1000 K. Attachment to CH3NCS yields exclusively SCN- ionic product but at a rate at 300 K that is below our detection threshold (k < 10-12 cm3 s-1). The rate coefficient increases rapidly with increasing temperature (k = 6 × 10-11 cm3 s-1 at 600 K), in a manner well described by an activation energy of 0.51 eV. Calculations at the B3LYP/def2-TZVPPD level suggest that attachment to CH3SCN proceeds through a dissociative state of CH3SCN-, while attachment to CH3NCS initially forms a weakly bound transient anion CH3NCS-* that isomerizes over an energetic barrier to yield SCN-. Kinetic modeling of the two systems is performed in an attempt to identify a kinetic signature differentiating the two mechanisms. The kinetic modeling reproduces the CH3NCS data only if dissociation through the transient anion is considered.

  4. Flora of Nam Kading National Protected Area I: a new species of yellow-flowered Strobilanthes (Acanthaceae), S. namkadingensis.

    PubMed

    Souladeth, Phetlasy; Tagane, Shuichiro; Zhang, Meng; Okabe, Norikazu; Yahara, Tetsukazu

    2017-01-01

    A new species of Acanthaceae, Strobilanthes namkadingensis Soulad. & Tagane from Nam Kading National Protected Area, Bolikhamxay Province, central Laos, is described and illustrated. It is characterized by long spicate inflorescences consisting of 6-32 flowers, yellow corolla, the absence of long white hairs on the bracts and 4-6 seeds per capsule. Three DNA barcode regions of the partial genes for the large sub-unit ribulose-1,5-bisphosphate carboxylase oxygenase ( rbcL ) and maturase K ( matK ) and internal transcribed spacers (ITS) are also provided.

  5. Spatio-temporal variability of modern sedimentation rates in Lake Nam Co, central Tibetan Plateau, China -- the first results from sediment traps

    NASA Astrophysics Data System (ADS)

    Wang, J.; Ju, J.; Daut, G.; Wang, Y.; Maeusbacher, R.; Zhu, L.

    2013-12-01

    As a big and deep lake in high altitude environment, Nam Co has played an important role in the past decade concerning paleoenvironmental change study. However, the modern process monitoring research is still insufficient in this lake to understand the variations in the modern sedimentation patterns. Sediment traps are widely used in lakes monitoring and research, providing the modern sedimentation rates (SR) and flux information as well as the materials for multidisciplinary studies. Here we present the first and preliminary result of spatio-temporal variability of SR in Nam Co based on one-year sediment traps data. Three integrated self-made traps mooring were deployed in different areas in Nam Co, which were eastern area (T1, ~57m depth), middle area (T2, ~93m depth) and western area (T3, ~62m depth). There were three layers traps in T1 and T3 station while four layers in T2 station. Additionally, a time-series automatic samples changing trap (Technicap PPS 3/3, France) was set up in the bottom (~90m depth) of T2 station with a sampling interval of two weeks. All traps were established in late May, 2012 and collected in Mid-September, 2012 for the first time. Then after winter time, samples were again collected in late May, 2013. Therefore, we got results for two periods, namely summer half year (May-September) and winter half year (September-next May). The results showed remarkable variation of SR vertically in all three stations, the bottom layers received much more materials than the up and middle layers. This fact could be attributed to the distinct influence of high density flows occurring at the lake bottom. This is also supported by multiprobe measurements showing high turbidity in the water body close to the bottom. In shallow areas (T1 and T3) the SR were higher than that of deep area (T2), which could probably reflect the different distance from the terrestrial source to the sites where the traps were deployed. In T1 and T2 stations, SR of winter half

  6. Sequential ChIP Protocol for Profiling Bivalent Epigenetic Modifications (ReChIP).

    PubMed

    Desvoyes, Bénédicte; Sequeira-Mendes, Joana; Vergara, Zaida; Madeira, Sofia; Gutierrez, Crisanto

    2018-01-01

    Identification of chromatin modifications, e.g., histone acetylation and methylation, among others, is widely carried out by using a chromatin immunoprecipitation (ChIP) strategy. The information obtained with these procedures is useful to gain an overall picture of modifications present in all cells of the population under study. It also serves as a basis to figure out the mechanisms of chromatin organization and gene regulation at the population level. However, the ultimate goal is to understand gene regulation at the level of single chromatin fibers. This requires the identification of chromatin modifications that occur at a given genomic location and within the same chromatin fiber. This is achieved by following a sequential ChIP strategy using two antibodies to distinguish different chromatin modifications. Here, we describe a sequential ChIP protocol (Re-ChIP), paying special attention to the controls needed and the required steps to obtain meaningful and reproducible results. The protocol is developed for young Arabidopsis seedlings but could be adapted to other plant materials.

  7. Adequacy of anti-tuberculosis drug prescriptions in Viet Nam

    PubMed Central

    Lauritsen, J. M.; Rieder, H. L.

    2012-01-01

    Setting: National Tuberculosis Program, Viet Nam, 2008. Objectives: To determine drug prescription adherence to national guidelines, to examine factors associated with an erroneous dosage of rifampin (RMP) and to evaluate the impact of an insufficient RMP dosage on treatment outcome. Methods: A representative sample of 30 treatment units was randomly selected. All patient treatment cards enrolled in these units were obtained, and data were double-entered and validated before calculating the adequacy of the individual drug prescriptions. Results: Of 3412 tuberculosis treatment cards, 3225 (94.5%) had information on treatment regimen and the patient’s weight. Treatment was successful in 89.4%. Prescriptions of tablets/vials conforming to recommendations were found for respectively 91.2%, 89.9%, 92.3% and 94.6% of the patients for RMP/isoniazid, pyrazinamide, ethambutol and streptomycin. Patients in the 25–39 kg weight bracket received insufficient dosages. This was almost entirely attributable to patients at the end of the weight bracket. Nevertheless, no significant association was found between treatment failure and death, body weight and insufficient RMP dosage. Conclusions: Adherence to national recommendations was high. RMP was given in insufficient dosage for patients at the end of a weight range bracket, but the under-dosage was small and did not measurably affect treatment outcome. PMID:26392937

  8. Adequacy of anti-tuberculosis drug prescriptions in Viet Nam.

    PubMed

    Hoa, N B; Lauritsen, J M; Rieder, H L

    2012-03-21

    National Tuberculosis Program, Viet Nam, 2008. To determine drug prescription adherence to national guidelines, to examine factors associated with an erroneous dosage of rifampin (RMP) and to evaluate the impact of an insufficient RMP dosage on treatment outcome. A representative sample of 30 treatment units was randomly selected. All patient treatment cards enrolled in these units were obtained, and data were double-entered and validated before calculating the adequacy of the individual drug prescriptions. Of 3412 tuberculosis treatment cards, 3225 (94.5%) had information on treatment regimen and the patient's weight. Treatment was successful in 89.4%. Prescriptions of tablets/vials conforming to recommendations were found for respectively 91.2%, 89.9%, 92.3% and 94.6% of the patients for RMP/isoniazid, pyrazinamide, ethambutol and streptomycin. Patients in the 25-39 kg weight bracket received insufficient dosages. This was almost entirely attributable to patients at the end of the weight bracket. Nevertheless, no significant association was found between treatment failure and death, body weight and insufficient RMP dosage. Adherence to national recommendations was high. RMP was given in insufficient dosage for patients at the end of a weight range bracket, but the under-dosage was small and did not measurably affect treatment outcome.

  9. Enterovirus serotypes in patients with central nervous system and respiratory infections in Viet Nam 1997-2010.

    PubMed

    B'Krong, Nguyen Thi Thuy Chinh; Minh, Ngo Ngoc Quang; Qui, Phan Tu; Chau, Tran Thi Hong; Nghia, Ho Dang Trung; Do, Lien Anh Ha; Nhung, Nguyen Ngoc; Van Vinh Chau, Nguyen; Thwaites, Guy; Van Tan, Le; van Doorn, H Rogier; Thanh, Tran Tan

    2018-04-12

    Enteroviruses are the most common causative agents of human illness. Enteroviruses have been associated with regional and global epidemics, recently, including with severe disease (Enterovirus A71 and D68), and are of interest as emerging viruses. Here, we typed Enterovirus A-D (EV) from central nervous system (CNS) and respiratory infections in Viet Nam. Data and specimens from prospective observational clinical studies conducted between 1997 and 2010 were used. Species and serotypes were determined using type-specific RT-PCR and viral protein 1 or 4 (VP1, VP4) sequencing. Samples from patients with CNS infection (51 children - 10 CSF and 41 respiratory/rectal swabs) and 28 adults (28 CSF) and respiratory infection (124 children - 124 respiratory swabs) were analysed. Twenty-six different serotypes of the four Enterovirus species (A-D) were identified, including EV-A71 and EV-D68. Enterovirus B was associated with viral meningitis in children and adults. Hand, foot and mouth disease associated Enteroviruses A (EV-A71 and Coxsackievirus [CV] A10) were detected in children with encephalitis. Diverse serotypes of all four Enterovirus species were found in respiratory samples, including 2 polio-vaccine viruses, but also 8 CV-A24 and 8 EV-D68. With the exception of EV-D68, the relevance of these viruses in respiratory infection remains unknown. We describe the diverse spectrum of enteroviruses from patients with CNS and respiratory infections in Viet Nam between 1997 and 2010. These data confirm the global circulation of Enterovirus genera and their associations and are important for clinical diagnostics, patient management, and outbreak response.

  10. In-plane chemical pressure essential for superconductivity in BiCh2-based (Ch: S, Se) layered structure

    PubMed Central

    Mizuguchi, Yoshikazu; Miura, Akira; Kajitani, Joe; Hiroi, Takafumi; Miura, Osuke; Tadanaga, Kiyoharu; Kumada, Nobuhiro; Magome, Eisuke; Moriyoshi, Chikako; Kuroiwa, Yoshihiro

    2015-01-01

    BiCh2-based compounds (Ch: S, Se) are a new series of layered superconductors, and the mechanisms for the emergence of superconductivity in these materials have not yet been elucidated. In this study, we investigate the relationship between crystal structure and superconducting properties of the BiCh2-based superconductor family, specifically, optimally doped Ce1−xNdxO0.5F0.5BiS2 and LaO0.5F0.5Bi(S1−ySey)2. We use powder synchrotron X-ray diffraction to determine the crystal structures. We show that the structure parameter essential for the emergence of bulk superconductivity in both systems is the in-plane chemical pressure, rather than Bi-Ch bond lengths or in-plane Ch-Bi-Ch bond angle. Furthermore, we show that the superconducting transition temperature for all REO0.5F0.5BiCh2 superconductors can be determined from the in-plane chemical pressure. PMID:26447333

  11. Direct observation of unimolecular decay of CH{sub 3}CH{sub 2}CHOO Criegee intermediates to OH radical products

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

    Fang, Yi; Liu, Fang; Lester, Marsha I., E-mail: milester@sas.upenn.edu

    2016-07-28

    The unimolecular decay of carbonyl oxide intermediates, known as Criegee intermediates, produced in alkene ozonolysis is a significant source of OH radicals in the troposphere. Here, the rate of appearance of OH radical products is examined directly in the time-domain for a prototypical alkyl-substituted Criegee intermediate, CH{sub 3}CH{sub 2}CHOO, following vibrational activation under collision-free conditions. Complementary statistical Rice–Ramsperger–Kassel–Marcus calculations of the microcanonical unimolecular decay rate for CH{sub 3}CH{sub 2}CHOO are also carried out at energies in the vicinity of the barrier for 1,4 hydrogen atom transfer that leads to OH products. Tunneling through the barrier, derived from high level electronicmore » structure calculations, contributes significantly to the decay rate. Infrared transitions of CH{sub 3}CH{sub 2}CHOO are identified in the CH stretch overtone region, which are detected by ultraviolet laser-induced fluorescence of the resultant OH products. The features observed are attributed to CH vibrational excitations and conformational forms utilizing insights from theory. Both experiment and theory yield unimolecular decay rates for CH{sub 3}CH{sub 2}CHOO of ca. 10{sup 7} s{sup −1}, which are slower than those obtained for syn-CH{sub 3}CHOO or (CH{sub 3}){sub 2}COO reported previously [Fang et al., J. Chem. Phys. 144, 061102 (2016)] at similar energies. Master equation modeling is also utilized to predict the thermal decay rate of CH{sub 3}CH{sub 2}CHOO under atmospheric conditions, giving a rate of 279 s{sup −1} at 298 K.« less

  12. Brief behavioural surveys in routine HIV sentinel surveillance: a new tool for monitoring the HIV epidemic in Viet Nam

    PubMed Central

    Hien, Nguyen Tran; Tuan, Nguyen Anh; Ha, Hoang Thi Thanh; Thang, Pham Hong; Ha, Nguyen Thi Thanh; Tuan, Le Anh; Quang, Tran Dai; Tram, Tran Hong; Le Hai, Nguyen; Huong, Phan Thi Thu; Son, Vo Hai; Duc, Bui Hoang; Nga, Nguyen Thien; Jacka, David; Sabin, Keith

    2015-01-01

    In this report we describe a new approach in HIV sentinel surveillance that was piloted in Viet Nam in 2009 and is currently being rolled out in all provinces. It comprises a brief behavioural questionnaire added to the HIV sentinel surveillance surveys conducted routinely among people who inject drugs, female sex workers and men who have sex with men. Timely reporting of data from this system has resulted in improvements to HIV prevention efforts for most at-risk populations. PMID:25960922

  13. Thermochemistry and kinetics for 2-butanone-1-yl radical (CH2·C(═O)CH2CH3) reactions with O2.

    PubMed

    Sebbar, N; Bozzelli, J W; Bockhorn, H

    2014-01-09

    Thermochemistry of reactants, intermediates, transition state structures, and products along with kinetics on the association of CH2·C(═O)CH2CH3 (2-butanone-1-yl) with O2 and dissociation of the peroxy adduct isomers are studied. Thermochemical properties are determined using ab initio (G3MP2B3 and G3) composite methods along with density functional theory (B3LYP/6-311g(d,p)). Entropy and heat capacity contributions versus temperature are determined from structures, vibration frequencies, and internal rotor potentials. The CH2·C(═O)CH2CH3 radical + O2 association results in a chemically activated peroxy radical with 27 kcal mol(-1) excess of energy. The chemically activated adduct can react to stabilized peroxy or hydroperoxide alkyl radical adducts, further react to lactones plus hydroxyl radical, or form olefinic ketones and a hydroperoxy radical. Kinetic parameters are determined from the G3 composite methods derived thermochemical parameters, and quantum Rice-Ramsperger-Kassel (QRRK) analysis to calculate k(E) with master equation analysis to evaluate falloff in the chemically activated and dissociation reactions. One new, not previously reported, peroxy chemistry reaction is presented. It has a low barrier path and involves a concerted reaction resulting in olefin formation, H2O elimination, and an alkoxy radical.

  14. Spatial And Temporal Patterns As Well As Major Influencing Factors Of Global And Diffuse Horizontal Irradiance Over China: 1960-2014

    NASA Astrophysics Data System (ADS)

    Wang, H.; Sun, F.

    2017-12-01

    Global Horizontal Irradiance (GHI) on Earth is a central element of climate systems. With changes in the climate and regional development, the patterns and influencing factors of GHI, in addition to presenting global consistency, are increasingly showing regional particularities. Based on data for GHI, Diffuse Horizontal Irradiance (DHI) and potential impact factors (geographical position, elevation, cloud cover, water vapor, and ground atmospheric transparency related variables) from 1960 to 2014 in China, we analyzed the pattern and major influencing factors of GHI and DHI. The results showed that the major influencing factors of the GHI spatial pattern were the total cloud cover (TCC) and relative humidity (RH) in China. Dividing all of China into two regions, the major factors were the water vapor pressure (WVP) in the northern region and TCC in the southern region. And we divided the GHI and DHI data into two periods (1960-1987 and 1988-2014) due to global dimming and brightening observed in China in the late 1980's. The temporal GHI showed that 31 of 58 decreased significantly with an average decreasing rate of 95 MJ.10yr-1 during the periods of 1960-2014 and 49 of 76 stations decreased significantly with an rate of 342 MJ.10yr-1 during 1960-1987, whereas 57 of 88 stations did not change and 24 stations increased significantly with an rate of 201 MJ.10yr-1 during the period of 1988-2014. The temporal DHI showed that 40 of 61sites did not change significantly from 1960 to 1987. The major influencing factors for temporal changes of GHI in nine typical cities from 1960 to 2013 were as follows: air quality-related variables in super cities, sandstorms and wind in desert oasis cities, clouds in cities with good air quality and a low cloud amount (LCA) and annual fog days (FD) in Chengdu. Overall, we identified characteristics of GHI and DHI based on global climate change and regional urban development and found that the spatial characteristics of GHI results for

  15. Computing energy levels of CH4, CHD3, CH3D, and CH3F with a direct product basis and coordinates based on the methyl subsystem.

    PubMed

    Zhao, Zhiqiang; Chen, Jun; Zhang, Zhaojun; Zhang, Dong H; Wang, Xiao-Gang; Carrington, Tucker; Gatti, Fabien

    2018-02-21

    Quantum mechanical calculations of ro-vibrational energies of CH 4 , CHD 3 , CH 3 D, and CH 3 F were made with two different numerical approaches. Both use polyspherical coordinates. The computed energy levels agree, confirming the accuracy of the methods. In the first approach, for all the molecules, the coordinates are defined using three Radau vectors for the CH 3 subsystem and a Jacobi vector between the remaining atom and the centre of mass of CH 3 . Euler angles specifying the orientation of a frame attached to CH 3 with respect to a frame attached to the Jacobi vector are used as vibrational coordinates. A direct product potential-optimized discrete variable vibrational basis is used to build a Hamiltonian matrix. Ro-vibrational energies are computed using a re-started Arnoldi eigensolver. In the second approach, the coordinates are the spherical coordinates associated with four Radau vectors or three Radau vectors and a Jacobi vector, and the frame is an Eckart frame. Vibrational basis functions are products of contracted stretch and bend functions, and eigenvalues are computed with the Lanczos algorithm. For CH 4 , CHD 3 , and CH 3 D, we report the first J > 0 energy levels computed on the Wang-Carrington potential energy surface [X.-G. Wang and T. Carrington, J. Chem. Phys. 141(15), 154106 (2014)]. For CH 3 F, the potential energy surface of Zhao et al. [J. Chem. Phys. 144, 204302 (2016)] was used. All the results are in good agreement with experimental data.

  16. Computing energy levels of CH4, CHD3, CH3D, and CH3F with a direct product basis and coordinates based on the methyl subsystem

    NASA Astrophysics Data System (ADS)

    Zhao, Zhiqiang; Chen, Jun; Zhang, Zhaojun; Zhang, Dong H.; Wang, Xiao-Gang; Carrington, Tucker; Gatti, Fabien

    2018-02-01

    Quantum mechanical calculations of ro-vibrational energies of CH4, CHD3, CH3D, and CH3F were made with two different numerical approaches. Both use polyspherical coordinates. The computed energy levels agree, confirming the accuracy of the methods. In the first approach, for all the molecules, the coordinates are defined using three Radau vectors for the CH3 subsystem and a Jacobi vector between the remaining atom and the centre of mass of CH3. Euler angles specifying the orientation of a frame attached to CH3 with respect to a frame attached to the Jacobi vector are used as vibrational coordinates. A direct product potential-optimized discrete variable vibrational basis is used to build a Hamiltonian matrix. Ro-vibrational energies are computed using a re-started Arnoldi eigensolver. In the second approach, the coordinates are the spherical coordinates associated with four Radau vectors or three Radau vectors and a Jacobi vector, and the frame is an Eckart frame. Vibrational basis functions are products of contracted stretch and bend functions, and eigenvalues are computed with the Lanczos algorithm. For CH4, CHD3, and CH3D, we report the first J > 0 energy levels computed on the Wang-Carrington potential energy surface [X.-G. Wang and T. Carrington, J. Chem. Phys. 141(15), 154106 (2014)]. For CH3F, the potential energy surface of Zhao et al. [J. Chem. Phys. 144, 204302 (2016)] was used. All the results are in good agreement with experimental data.

  17. The Effect of Intermittent Antenatal Iron Supplementation on Maternal and Infant Outcomes in Rural Viet Nam: A Cluster Randomised Trial

    PubMed Central

    Hanieh, Sarah; Ha, Tran T.; Simpson, Julie A.; Casey, Gerard J.; Khuong, Nguyen C.; Thoang, Dang D.; Thuy, Tran T.; Pasricha, Sant-Rayn; Tran, Thach D.; Tuan, Tran; Dwyer, Terence; Fisher, Jane; Biggs, Beverley-Ann

    2013-01-01

    Background Anemia affects over 500 million women, and in pregnancy is associated with impaired maternal and infant outcomes. Intermittent antenatal iron supplementation is an attractive alternative to daily dosing; however, the impact of this strategy on infant outcomes remains unclear. We compared the effect of intermittent antenatal iron supplementation with daily iron supplementation on maternal and infant outcomes in rural Viet Nam. Methods and Findings This cluster randomised trial was conducted in Ha Nam province, Viet Nam. 1,258 pregnant women (<16 wk gestation) in 104 communes were assigned to daily iron–folic acid (IFA), twice weekly IFA, or twice weekly multiple micronutrient (MMN) supplementation. Primary outcome was birth weight. Mean birth weight was 3,148 g (standard deviation 416). There was no difference in the birth weights of infants of women receiving twice weekly IFA compared to daily IFA (mean difference [MD] 28 g; 95% CI −22 to 78), or twice weekly MMN compared to daily IFA (MD −36.8 g; 95% CI −82 to 8.2). At 32 wk gestation, maternal ferritin was lower in women receiving twice weekly IFA compared to daily IFA (geometric mean ratio 0.73; 95% CI 0.67 to 0.80), and in women receiving twice weekly MMN compared to daily IFA (geometric mean ratio 0.62; 95% CI 0.57 to 0.68), but there was no difference in hemoglobin levels. Infants of mothers who received twice weekly IFA had higher cognitive scores at 6 mo of age compared to those who received daily IFA (MD 1.89; 95% CI 0.23 to 3.56). Conclusions Twice weekly antenatal IFA or MMN did not produce a clinically important difference in birth weight, when compared to daily IFA supplementation. The significant improvement in infant cognitive outcomes at 6 mo of age following twice weekly antenatal IFA requires further exploration, and provides additional support for the use of intermittent, rather than daily, antenatal IFA in populations with low rates of iron deficiency. Trial registration

  18. Patterns and risk factors of inconsistent condom use among men who have sex with men in Viet Nam: Results from an Internet-based cross-sectional survey.

    PubMed

    García, Macarena C; Duong, Quyen L; Mercer, Licelot C Eralte; Meyer, Samantha B; Koppenhaver, Todd; Ward, Paul R

    2014-01-01

    Survey data from men who have sex with men (MSM) in Asian cities indicate drastic increases in HIV prevalence. It is unknown which factors are most important in driving these epidemics. The objective of this study was to identify patterns of condom use among MSM Internet users living in Viet Nam, as well as risk factors associated with inconsistent condom use and non-condom use. A national Internet-based survey of sexual behaviours was administered in 2011. Results showed that 44.9% of MSM reported not using a condom during their last anal sex encounter with a male partner. MSM were less likely to report condom use during anal sex with long-term partners than with casual partners. Twenty-three and a half per cent of MSM surveyed had ever taken an HIV test and received the results. Study findings highlight the urgent need for targeted strategies focused on increasing the rate of consistent condom use during anal sex with male partners among MSM in Viet Nam.

  19. Common perinatal mental disorders in northern Viet Nam: community prevalence and health care use

    PubMed Central

    Tran, Thach; La, Buoi thi; Kriitmaa, Kelsi; Rosenthal, Doreen; Tran, Tuan

    2010-01-01

    Abstract Objective To establish the prevalence of common perinatal mental disorders their determinants, and their association with preventive health care use among women in one rural and one urban province in northern Viet Nam. Methods We conducted a cross-sectional survey of cohorts of pregnant women and mothers of infants recruited systematically in 10 randomly-selected communes. The women participated in psychiatrist-administered structured clinical interviews and separate structured interviews to assess sociodemographic factors, reproductive health, the intimate partner relationship, family violence and the use of preventive and psychiatric health care. Associations between these variables and perinatal mental disorders were explored through univariate analyses and multivariable logistic regression. Findings Among women eligible for the study (392), 364 (93%) were recruited. Of these, 29.9% (95% confidence interval, CI: 25.20–34.70) were diagnosed with a common perinatal mental disorder (CPMD). The frequency of such disorders during pregnancy and in the postpartum period was the same. Their prevalence was higher among women in rural provinces (odds ratio, OR: 2.17; 95% CI: 1.19–3.93); exposed to intimate partner violence (OR: 2.11; 95% CI: 1.12–3.96); fearful of other family members (OR: 3.36; 95% CI: 1.05–10.71) or exposed to coincidental life adversity (OR: 4.40; 95% CI: 2.44–7.93). Fewer women with a CPMD used iron supplements than women without a CPMD, but the results were not statistically significant (P = 0.05). None of the women studied had ever received mental health care. Conclusion Perinatal depression and anxiety are prevalent in women in northern Viet Nam. These conditions are predominantly determined by social factors, including rural residence, poverty and exposure to family violence. At present the needs of women with common perinatal mental disorders are unrecognized and not attended to and their participation in essential

  20. CH_{4} production in the deep soil as a source of stem CH_{4} emission in Fagus sylvatica}

    NASA Astrophysics Data System (ADS)

    Maier, Martin; Machacova, Katerina; Urban, Otmar; Lang, Friederike

    2017-04-01

    Predicting greenhouse gas (GHG) fluxes on a global scale requires understanding fluxes on the local scale. Understanding GHG processes in soil-plant-atmosphere systems is essential to understand and mitigate GHG fluxes on the local scale. Forests are known to act as carbon sink. Yet, trees at waterlogged sites are known to emit large amounts of CH4, what can offset the positive GHG balance due the CO2 that is sequestered as wood. Generally, upland trees like European beech (Fagus sylvatica L.) are assumed not to emit CH4, and the upland forest soils are regarded as CH4 sinks. Soil-atmosphere fluxes and stem-atmosphere fluxes of CH4 were studied together with soil gas profiles at two upland beech forest sites in Germany and Czech Republic. Soil was a net CH4 sink at both sites. While most trees showed no or low emissions, one beech tree had exorbitant CH4 emissions that were higher than the CH4 sink capacity of the soil. A soil survey showed strong redoximorphic color patterns in the soil adjacent to this tree. Although the soil around the tree was taking up CH4, the soil gas profiles around this tree showed CH4 production at a soil depth >0.3 m. We interpret the coincidence of the production of CH4 in the deep soil below the beech with the large stem emissions as strong hint that there is a transport link between the soil and stem. We think that the root system represents a preferential transport system for CH4 despite the fact that beech roots usually do not have a special gas transport tissue. The observed CH4 stem emissions represent an important CH4 flux in this ecosystem, and, thus, should be considered in future research. Acknowledgement This research was supported by the Czech Academy of Sciences and the German Academic Exchange Service within the project "Methane (CH4) and nitrous oxide (N2O) emissions from Fagus sylvatica trees" (DAAD-15-03), the Czech Science Foundation (17-18112Y), National Programme for Sustainability I (LO1415) and project DFG (MA 5826

  1. Experimental and Computational Study fo CH, CH*, and OH* in an Axisymmetric Laminar Diffusion Flame

    NASA Technical Reports Server (NTRS)

    Walsh, K. T.

    1998-01-01

    In this study, we extend the results of previous combined numerical and experimental investigations of an axisymmetric laminar diffusion flame in which difference Raman spectroscopy, laser-induced fluorescence (LIF), and a multidimensional flame model were used to generate profiles of the temperature and major and minor species. A procedure is outlined by which the number densities of ground-state CH (X(sup 2)II) excited-state CH (A(sup 2)Delta, denoted CH*), and excited-state OH (A(sup 2)Sigma, denoted OH*) are measured and modeled. CH* and OH* number densities are deconvoluted from line-of-sight flame-emission measurements. Ground-state CH is measured using linear LIF. The computations are done with GRI Mech 2.11 as well as an alternate hydrocarbon mechanism. In both cases, additional reactions for the production and consumption of CH* and OH* are added from recent kinetic studies. Collisional quenching and spontaneous emission are responsible for the de-excitation of the excited-state radicals. As with our previous investigations, GRI Mech 2.11 continues to produce very good agreement with the overall flame length observed in the experiments, while significantly under predicting the flame lift-off height. The alternate kinetic scheme is much more accurate in predicting lift-off height but overpredicts the over-all flame length. Ground-state CH profiles predicted with GRI Mech 2.11 are in excellent agreement with the corresponding measurements, regarding both spatial distribution and absolute concentration (measured at 4 ppm) of the CH radical. Calculations of the excited-state species show reasonable agreement with the measurements as far as spatial distribution and overall characteristics are concerned. For OH*, the measured peak mole fraction, 1.3 x 10(exp -8), compared well with computed peaks, while the measured peak level for CH*, 2 x 10(exp -9), was severely underpredicted by both kinetic schemes, indicating that the formation and destruction kinetics

  2. Infrared-Terahertz Double-Resonance Spectroscopy of CH3F and CH3Cl at Atmospheric Pressure

    DTIC Science & Technology

    2012-05-16

    coincidence with the RQ3(6) rovibrational transition in CH3 35Cl [Fig. 4(b)]. At atmospheric pressure, nine more P -, Q-, and R-branch rovibrational...the double-resonance signatures of all IR-THz pump-probe coincidences at atmospheric pressure for 12CH3F and CH3 35Cl 052507-11050-2947/2012/85(5...were calculated using the rotational constants listed in Tables I and II. For CH3F, the standard P - type (J = − 1), Q-type (J = 0), and R-type (J

  3. Do Zero-Cost Workers’ Compensation Medical Claims Really Have Zero Costs?

    PubMed Central

    Asfaw, Abay; Rosa, Roger; Mao, Rebecca

    2015-01-01

    Objective Previous research suggests that non–workers’ compensation (WC) insurance systems, such as group health insurance (GHI), Medicare, or Medicaid, at least partially cover work-related injury and illness costs. This study further examined GHI utilization and costs. Methods Using two-part model, we compared those outcomes immediately after injuries for which accepted WC medical claims made zero or positive medical payments. Results Controlling for pre-injury GHI utilization and costs and other covariates, our results indicated that post-injury GHI utilization and costs increased regardless of whether a WC medical claim was zero or positive. The increases were highest for zero-cost WC medical claims. Conclusion Our national estimates showed that zero-cost WC medical claims alone could cost the GHI $212 million per year. PMID:24316724

  4. ChIP-PIT: Enhancing the Analysis of ChIP-Seq Data Using Convex-Relaxed Pair-Wise Interaction Tensor Decomposition.

    PubMed

    Zhu, Lin; Guo, Wei-Li; Deng, Su-Ping; Huang, De-Shuang

    2016-01-01

    In recent years, thanks to the efforts of individual scientists and research consortiums, a huge amount of chromatin immunoprecipitation followed by high-throughput sequencing (ChIP-seq) experimental data have been accumulated. Instead of investigating them independently, several recent studies have convincingly demonstrated that a wealth of scientific insights can be gained by integrative analysis of these ChIP-seq data. However, when used for the purpose of integrative analysis, a serious drawback of current ChIP-seq technique is that it is still expensive and time-consuming to generate ChIP-seq datasets of high standard. Most researchers are therefore unable to obtain complete ChIP-seq data for several TFs in a wide variety of cell lines, which considerably limits the understanding of transcriptional regulation pattern. In this paper, we propose a novel method called ChIP-PIT to overcome the aforementioned limitation. In ChIP-PIT, ChIP-seq data corresponding to a diverse collection of cell types, TFs and genes are fused together using the three-mode pair-wise interaction tensor (PIT) model, and the prediction of unperformed ChIP-seq experimental results is formulated as a tensor completion problem. Computationally, we propose efficient first-order method based on extensions of coordinate descent method to learn the optimal solution of ChIP-PIT, which makes it particularly suitable for the analysis of massive scale ChIP-seq data. Experimental evaluation the ENCODE data illustrate the usefulness of the proposed model.

  5. The photolysis of CH3ONO

    NASA Technical Reports Server (NTRS)

    Wiebe, H. A.; Heicklen, J.

    1972-01-01

    The photolysis of CH3ONO, alone and in the presence of NO, NO-N2 mixtures, and NO-CO mixtures was studied between 25 and 150 C. The major products are CH2O, N2O, and H2O. The quantum yields of N2O were measured. The N2O yield is large at low pressures but approaches a high-pressure limiting value of 0.055 at all temperatures as the excited CH3O produced in the primary step is stabilized by collision. In the presence of excess CO, and N2O yield drops, and CO2 is produced (though not in sufficient amounts to account for the drop in N2O). When pure CH2ONO is photolyzed, CO is produced and NO accumulates in the system. Both products are formed in related processes and result from CH3O attack on CH2O.

  6. Work outside the home is the primary barrier to exclusive breastfeeding in rural Viet Nam: insights from mothers who exclusively breastfed and worked.

    PubMed

    Dearden, Kirk A; Quan, Le Nga; Do, Mai; Marsh, David R; Pachón, Helena; Schroeder, Dirk G; Lang, Tran Thi

    2002-12-01

    This study assessed barriers to exclusive breastfeeding in rural Viet Nam and identified how a few mothers were able to exclusively breastfeed despite barriers. A cross-sectional quantitative and qualitative assessment was carried out among 120 mothers of infants less than six months old in northern Viet Nam. Only 24% of the mothers exclusively breastfed. Adjusting for infant's age and who attended delivery, the risk of not exclusively breastfeeding was 14.0 times greater for women who had returned to work than for women who had not. Exclusively breastfeeding mothers (n = 4) who worked differed from other mothers in important ways. They all felt they had enough milk, all knew the appropriate time to introduce foods and liquids, and most were supported in their breastfeeding decisions by commune health workers and family members. This research suggests strategies that can be implemented now to increase exclusive breastfeeding in rural work environments. These include improving knowledge about the introduction of water and semi-solids, addressing perceptions of milk insufficiency, securing support from others, and presenting mothers with options for exclusively breastfeeding, even when they work outside the home.

  7. Using exceedance probabilities to detect anomalies in routinely recorded animal health data, with particular reference to foot-and-mouth disease in Viet Nam.

    PubMed

    Richards, K K; Hazelton, M L; Stevenson, M A; Lockhart, C Y; Pinto, J; Nguyen, L

    2014-10-01

    The widespread availability of computer hardware and software for recording and storing disease event information means that, in theory, we have the necessary information to carry out detailed analyses of factors influencing the spatial distribution of disease in animal populations. However, the reliability of such analyses depends on data quality, with anomalous records having the potential to introduce significant bias and lead to inappropriate decision making. In this paper we promote the use of exceedance probabilities as a tool for detecting anomalies when applying hierarchical spatio-temporal models to animal health data. We illustrate this methodology through a case study data on outbreaks of foot-and-mouth disease (FMD) in Viet Nam for the period 2006-2008. A flexible binomial logistic regression was employed to model the number of FMD infected communes within each province of the country. Standard analyses of the residuals from this model failed to identify problems, but exceedance probabilities identified provinces in which the number of reported FMD outbreaks was unexpectedly low. This finding is interesting given that these provinces are on major cattle movement pathways through Viet Nam. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Spatial distribution of CH3 and CH2 radicals in a methane rf discharge

    NASA Astrophysics Data System (ADS)

    Sugai, H.; Kojima, H.; Ishida, A.; Toyoda, H.

    1990-06-01

    Spatial distributions of neutral radicals CH3 and CH2 in a capacitively coupled rf glow discharge of methane were measured by threshold ionization mass spectrometry. A strong asymmetry of the density profile was found for the CH2 radical in the high-pressure (˜100 mTorr) discharge. In addition, comprehensive measurements of electron energy distribution, ionic composition, and radical sticking coefficient were made to use as inputs to theoretical modeling of radicals in the methane plasma. The model predictions agree substantially with the measured radical distributions.

  9. Thz Spectroscopy of 12CH^+, 13CH^+, and 12CD^+

    NASA Astrophysics Data System (ADS)

    Yu, Shanshan; Drouin, Brian; Pearson, John; Amano, Takayoshi

    2015-06-01

    In 1937, Dunham detected a couple of unidentified lines in near-UV, and later Douglas and Herzberg identified them based on their laboratory observations to be low-J electronic transitions of CH^+. The electronic spectra, in particular the A^1Π-X^1σ^+ band, have been investigated extensively. On the other hand, the pure rotational transitions have not been studied so extensively. Only the lowest rotational transition, J=1-0, was observed in the laboratory for the normal species, 13CH^+, and CD^+. Based on the laboratory frequency, CH^+ was detected in star forming regions with the Hershel space observatory. Cernicharo et al identified pure rotational transitions from J=2-1 to J=6-5 in the far-infrared region in the ISO spectrum of the planetary nebula NGC 7027. The ISO spectra, however, were of low-resolution, so high-resolution spectroscopic observation is highly desirable. In this presentation, we have extended the measurements to higher-J lines up to 2 THz. For production of CH^+, an extended negative glow discharge in a gas mixture of CH_4 (˜ 0.5 mTorr) diluted in He (˜ 60 mTorr) was used. The optimum discharge current was about 15 mA and the axial magnetic filed to 160 Gauss was applied up. The discharge cell was cooled down to liquid nitrogen temperature. Several frequency multiplier chains, developed at JPL and purchased from Virginia Diodes, were used as THz radiation sources. New THz measurements are not only useful for providing better characterization of spectroscopic properties but also will serve as starting point for astronomical observations. T. Dunham, Publ. Astron. Soc. Pac., 49,~26 (1937) A. E. Douglas and G. Herzberg, Ap. J. 94,~381 (1941) T. Amano, Ap.J.Lett., 716, L1 (2010) T. Amano, J. Chem. Phys., 133, 244305 (2010) J. Cernicharo et al., Ap. J. Lett., 483, L65 (1997)

  10. Shared epitopes of glycoprotein A and protein 4.1 defined by antibody NaM10-3C10.

    PubMed

    Rasamoelisolo, M; Czerwinski, M; Willem, C; Blanchard, D

    1998-06-01

    We have produced the murine monoclonal antibody (MAb) NaM70-3C10 (IgM) from splenocytes of mice immunized with human red blood cells (RBCs). The MAb agglutinated untreated as well as trypsin, chymotrypsin, neuraminidase, or ficin-treated RBCs from controls. In contrast, control RBCs treated with papaine or bromelaine were not agglutinated. On immunoblots, the MAb bound to glycophorin A (GPA) and to a 80 kDa protein identified as protein 4.1. Analysis by agglutination of variant RBCs carrying hybrid glycophorins made of the N-terminus (amino acids 1-58) of GPA and of the C-terminus (amino acids 27-72) of glycophorin B (GPB) and competition-inhibition test using purified GPA and a synthetic peptide corresponding to the amino acid sequence 48-58 of GPA demonstrated that the epitope is located within residues 48-58 of GPA. Epitope analysis with immobilized peptides showed that the MAb recognizes the sequence 53Pro-Pro-Glu-Glu-GIu58 of GPA. A homologous sequence is also present within amino acids 395 to 405 of protein 4.1. Finally, the MAb bound to 16 kDa chymotryptic peptide of protein 4.1, which carries the above amino acid sequence. In conclusion, it may be assumed that NaM70-3C10 specifically recognizes a common epitope on the extracellular domain of GPA and on the intracellular protein 4.1; this specificity explains the persistence of the 80 kDa band on blots when RBCs are treated with papain.

  11. Prevalence of resistance to second-line tuberculosis drug among multidrug-resistant tuberculosis patients in Viet Nam, 2011

    PubMed Central

    Tran, Huong Thi Giang; Bui, Quyen Thi Tu

    2016-01-01

    Introduction Extensively drug-resistant tuberculosis (XDR-TB) represents an emerging public health problem worldwide. According to the World Health Organization, an estimated 9.7% of multidrug-resistant TB (MDR-TB) cases are defined as XDR-TB globally. The objective of this study was to determine the prevalence of drug resistance to second-line TB drugs among MDR-TB cases detected in the Fourth National Anti-Tuberculosis Drug Resistance Survey in Viet Nam. Methods Eighty clusters of TB cases were selected using a probability-proportion-to-size approach. To identify MDR-TB cases, drug susceptibility testing (DST) was performed for the four major first-line TB drugs. DST of second-line drugs (ofloxacin, amikacin, kanamycin, capreomycin) was performed on isolates from MDR-TB cases to identify pre-XDR and XDR cases. Results A total of 1629 smear-positive TB cases were eligible for culture and DST. Of those, DST results for first-line drugs were available for 1312 cases, and 91 (6.9%) had MDR-TB. Second-line DST results were available for 84 of these cases. Of those, 15 cases (17.9%) had ofloxacin resistance and 6.0% were resistant to kanamycin and capreomycin. Five MDR-TB cases (6.0%) met the criteria of XDR-TB. Conclusion This survey provides the first estimates of the proportion of XDR-TB among MDR-TB cases in Viet Nam and provides important information for local policies regarding second-line DST. Local policies and programmes that are geared towards TB prevention, early diagnosis and treatment with effective regimens are of high importance. PMID:27508089

  12. Prevalence of resistance to second-line tuberculosis drug among multidrug-resistant tuberculosis patients in Viet Nam, 2011.

    PubMed

    Nguyen, Hoa Binh; Nguyen, Nhung Viet; Tran, Huong Thi Giang; Nguyen, Hai Viet; Bui, Quyen Thi Tu

    2016-01-01

    Extensively drug-resistant tuberculosis (XDR-TB) represents an emerging public health problem worldwide. According to the World Health Organization, an estimated 9.7% of multidrug-resistant TB (MDR-TB) cases are defined as XDR-TB globally. The objective of this study was to determine the prevalence of drug resistance to second-line TB drugs among MDR-TB cases detected in the Fourth National Anti-Tuberculosis Drug Resistance Survey in Viet Nam. Eighty clusters of TB cases were selected using a probability-proportion-to-size approach. To identify MDR-TB cases, drug susceptibility testing (DST) was performed for the four major first-line TB drugs. DST of second-line drugs (ofloxacin, amikacin, kanamycin, capreomycin) was performed on isolates from MDR-TB cases to identify pre-XDR and XDR cases. A total of 1629 smear-positive TB cases were eligible for culture and DST. Of those, DST results for first-line drugs were available for 1312 cases, and 91 (6.9%) had MDR-TB. Second-line DST results were available for 84 of these cases. Of those, 15 cases (17.9%) had ofloxacin resistance and 6.0% were resistant to kanamycin and capreomycin. Five MDR-TB cases (6.0%) met the criteria of XDR-TB. This survey provides the first estimates of the proportion of XDR-TB among MDR-TB cases in Viet Nam and provides important information for local policies regarding second-line DST. Local policies and programmes that are geared towards TB prevention, early diagnosis and treatment with effective regimens are of high importance.

  13. MALACOLOGICAL INVESTIGATION OF THE FULLY OPERATIONAL NAM THEUN 2 HYDROELECTRIC DAM PROJECT IN KHAMMOUANE PROVINCE, CENTRAL LAO PDR.

    PubMed

    Sri-aroon, Pusadee; Chusongsang, Phiraphol; Chusongsang, Yupa; Limpanont, Yanin; Surinthwong, Pornpimol; Vongphayloth, Khamsing; Brey, Paul T

    2015-09-01

    We conducted a malacological investigation in four districts of the Nam Theun 2 (NT2) hydroelectric dam project area, Khammouane Province, central Lao PDR (Nakai, Gnommalath, Mahaxai and Xe Bang Fai), after the first and second years of full operation in March 2010 and November 2011 to determine health risks for humans. A total 10,863 snail specimens (10 families/23 species) from 57 sampling stations and 12,902 snail specimens (eight families/21 species) from 66 sampling stations were collected in 2010 and 2011, respectively. Neotricula aperta (gamma race), the intermediate host for Schistosoma mekongi, was found in large numbers (5,853 specimens) in 2010 in Nam Gnom (downstream) at Station 25 (Mueang Gnommalath: Gnommalath District) and in fewer numbers (170 specimens) at Station 26 (Ban Thathod: Gnommalath District). In 2011, significantly fewer numbers (434 specimens) of N. aperta were found at Station 25. No snails were found to be infected with S. mekongi; however, 3.6% and 0.45% of Bithynia (D.). s. goniomphalos specimens collected were found to be infected with Opisthorchis viverrini (human liver fluke) during 2010 and 2011, respectively. Pomacea canaliculata, the rice crop pest, the intermediate host of Angiostrongylus (Parastrongylus) cantonensis, was found in the greatest numbers during 2010 and 2011; the prevalence increased significantly from 1.3% in 2010 to 53.3% in 2011. We also found seasonal variation in snail populations in terms of abundance and diversity. The snail fauna and risk for transmission of parasitic diseases need to be monitored continuously to evaluate the long-term impact of the dam project.

  14. BariumCopperChFluorine (Ch = Sulfur, Selenium, Tellurium) p-type transparent conductors

    NASA Astrophysics Data System (ADS)

    Zakutayev, Andriy

    BaCuChF (Ch = S, Se, Te) materials are chalcogen-based transparent conductors with wide optical band gaps (2.9 -- 3.5 eV) and a high concentration of free holes (1018 -- 1020 cm-3 ) caused by the presence of copper vacancies. Chalcogen vacancies compensate copper vacancies in these materials, setting the Fermi level close to the valence band maximum. BaCuChF thin film solid solutions prepared by pulsed laser deposition (PLD) have tunable properties, such as lattice constants, conductivity and optical band gaps. BaCuSF and BaCuSeF materials also feature room-temperature stable 3D excitons with spin-orbit-split levels. BaCuTeF has forbidden lowest-energy optical transitions which extends its transparency range. BaCuChF surfaces oxidize when exposed to air, but can be protected using Ch capping layers. Polycrystalline BaCuSeF thin films have a 4.85 eV work function, a 0.11 eV hole injection barrier into ZnPc, and 0.00 eV valence band offset with ZnTe. BaCuSeF should have s similar band offset and similar interfacial properties with CdTe and Cu(InGa)Se2, and BaCuSF should have no valence band offset with Cu2ZnSnS4, according to the transitivity rule. Therefore, BaCuSeF is suitable for applications as a p-layer in organic light-emitting diodes, p-i-n double-heterojunction and tandem chalcogenide solar cells.

  15. Carbon-Hydrogen (C-H) Bond Activation at PdIV: A Frontier in C-H Functionalization Catalysis.

    PubMed

    Topczewski, Joseph J; Sanford, Melanie S

    2015-01-01

    The direct functionalization of carbon-hydrogen (C-H) bonds has emerged as a versatile strategy for the synthesis and derivatization of organic molecules. Among the methods for C-H bond activation, catalytic processes that utilize a Pd II /Pd IV redox cycle are increasingly common. The C-H activation step in most of these catalytic cycles is thought to occur at a Pd II centre. However, a number of recent reports have suggested the feasibility of C-H cleavage occurring at Pd IV complexes. Importantly, these latter processes often result in complementary reactivity and selectivity relative to analogous transformations at Pd II . This Mini Review highlights proposed examples of C-H activation at Pd IV centres. Applications of this transformation in catalysis as well as mechanistic details obtained from stoichiometric model studies are discussed. Furthermore, challenges and future perspectives for the field are reviewed.

  16. Methane Provenance Determined by CH2D2 and 13CH3D Abundances

    NASA Astrophysics Data System (ADS)

    Kohl, I. E.; Giunta, T.; Warr, O.; Ash, J. L.; Ruffine, L.; Sherwood Lollar, B.; Young, E. D.

    2017-12-01

    Determining the provenance of naturally occurring methane gases is of major interest to energy companies and atmospheric climate modelers, among others. Bulk isotopic compositions and other geochemical tracers sometimes fail to provide definitive determinations of sources of methane due to complications from mixing and complicated chemical pathways of origin. Recent measurements of doubly-substituted isotopologues of methane, CH2D2 (UCLA) and 13CH3D (UCLA, CalTech, and MIT) have allowed for major improvements in sourcing natural methane gases. Early work has focused on formation temperatures obtained when the relative abundances of both doubly-substituted mass-18 species are consistent with internal equilibrium. When methane gases do not plot on the thermodynamic equilibrium curve in D12CH2D2 vs D13CH3D space, temperatures determined from D13CH3D values alone are usually spurious, even when appearing reasonable. We find that the equilibrium case is actually rare and almost exclusive to thermogenic gases produced at temperatures exceeding 100°C. All other relevant methane production processes appear to generate gases that are not in isotopologue-temperature equilibrium. When gases show departures from equilibrium as determined by the relationship between CH2D2 and 13CH3D abundances, data fall within empirically defined fields representing formation pathways. These fields are thus far consistent between different geological settings and and between lab experiments and natural samples. We have now defined fields for thermogenic gas production, microbial methanogenesis, low temperature abiotic (Sabatier) synthesis and higher temperature FTT synthesis. The majority of our natural methane data can be explained by mixing between end members originating within these production fields. Mixing can appear complex, resulting in both hyper-clumped and anti-clumped isotopologue abundances. In systems where mixtures dominate and end-members are difficult to sample, mixing models

  17. Translations on North Korea, Number 537

    DTIC Science & Technology

    1977-07-05

    Kim Yong -chu, then director of the party’s agitprop department. In the second half of the 1960’s he was named director of the culture and...that he became widely known. At the 7th plenum of the Central Committee, Ch’oe Yong -kin and Kim II proposed Kim Chong-il as the successor to Kim Il...visit of the NCNA delegation were the following: Kim Yong -nam Kim Song-köl Kim Si-hak Kim Yong -sun Ch’ae Chun-pyong Chong

  18. The catalytic effects of H2CO3, CH3COOH, HCOOH and H2O on the addition reaction of CH2OO + H2O → CH2(OH)OOH

    NASA Astrophysics Data System (ADS)

    Zhang, Tianlei; Lan, Xinguang; Wang, Rui; Roy, Soumendra; Qiao, Zhangyu; Lu, Yousong; Wang, Zhuqing

    2018-07-01

    The addition reaction of CH2OO + H2O → CH2(OH)OOH without and with X (X = H2CO3, CH3COOH and HCOOH) and H2O was studied at CCSD(T)/6-311+ G(3df,2dp)//B3LYP/6-311+G(2d,2p) level of theory. Our results show that X can catalyse CH2OO + H2O → CH2(OH)OOH reaction both by increasing the number of rings, and by adding the size of the ring in which ring enlargement by COOH moiety of X inserting into CH2OO...H2O is favourable one. Water-assisted CH2OO + H2O → CH2(OH)OOH can occur by H2O moiety of (H2O)2 or the whole (H2O)2 forming cyclic structure with CH2OO, where the latter form is more favourable. Because the concentration of H2CO3 is unknown, the influence of CH3COOH, HCOOH and H2O were calculated within 0-30 km altitude of the Earth's atmosphere. The results calculated within 0-5 km altitude show that H2O and HCOOH have obvious effect on enhancing the rate with the enhancement factors are, respectively, 62.47%-77.26% and 0.04%-1.76%. Within 5-30 km altitude, HCOOH has obvious effect on enhancing the title rate with the enhancement factor of 2.69%-98.28%. However, compared with the reaction of CH2OO + HCOOH, the rate of CH2OO...H2O + HCOOH is much slower.

  19. Training Management in the CH-46E Community After MAWTS-1 Stands Down Its CH-46E Division

    DTIC Science & Technology

    2012-04-23

    SHOULD INCLUDE THE FOREGOING STATEMENT. QUOTATION FROM, ABSTRACTION FROM, OR REPRODUCTION OF ALL OR ANY PART OF THIS DOCUMENT IS PERMITTED...HMH) currently fly either the CH-53D Sea Stallion or the CH-53E Super Stallion helicopters. Those units that fly the CH-53D Sea Stallion are in the...process of converting to the CH-53E Super Stallion or will transition the squadrons to medium lift assault support platforms.5 The HMHs currently

  20. Degraded Land Restoration in Reinstating CH4 Sink

    PubMed Central

    Singh, Jay Shankar; Gupta, Vijai K.

    2016-01-01

    Methane (CH4), a potent greenhouse gas, contributes about one third to the global green house gas emissions. CH4-assimilating microbes (mostly methanotrophs) in upland soils play very crucial role in mitigating the CH4 release into the atmosphere. Agricultural, environmental, and climatic shifts can alter CH4 sink profiles of soils, likely through shifts in CH4-assimilating microbial community structure and function. Landuse change, as forest and grassland ecosystems altered to agro-ecosystems, has already attenuated the soil CH4 sink potential, and are expected to be continued in the future. We hypothesized that variations in CH4 uptake rates in soils under different landuse practices could be an indicative of alterations in the abundance and/or type of methanotrophic communities in such soils. However, only a few studies have addressed to number and methanotrophs diversity and their correlation with the CH4 sink potential in soils of rehabilitated/restored lands. We focus on landuse practices that can potentially mitigate CH4 gas emissions, the most prominent of which are improved cropland, grazing land management, use of bio-fertilizers, and restoration of degraded lands. In this perspective paper, it is proposed that restoration of degraded lands can contribute considerably to improved soil CH4 sink strength by retrieving/conserving abundance and assortment of efficient methanotrophic communities. We believe that this report can assist in identifying future experimental directions to the relationships between landuse changes, methane-assimilating microbial communities and soil CH4 sinks. The exploitation of microbial communities other than methanotrophs can contribute significantly to the global CH4 sink potential and can add value in mitigating the CH4 problems. PMID:27379053

  1. Degraded Land Restoration in Reinstating CH4 Sink.

    PubMed

    Singh, Jay Shankar; Gupta, Vijai K

    2016-01-01

    Methane (CH4), a potent greenhouse gas, contributes about one third to the global green house gas emissions. CH4-assimilating microbes (mostly methanotrophs) in upland soils play very crucial role in mitigating the CH4 release into the atmosphere. Agricultural, environmental, and climatic shifts can alter CH4 sink profiles of soils, likely through shifts in CH4-assimilating microbial community structure and function. Landuse change, as forest and grassland ecosystems altered to agro-ecosystems, has already attenuated the soil CH4 sink potential, and are expected to be continued in the future. We hypothesized that variations in CH4 uptake rates in soils under different landuse practices could be an indicative of alterations in the abundance and/or type of methanotrophic communities in such soils. However, only a few studies have addressed to number and methanotrophs diversity and their correlation with the CH4 sink potential in soils of rehabilitated/restored lands. We focus on landuse practices that can potentially mitigate CH4 gas emissions, the most prominent of which are improved cropland, grazing land management, use of bio-fertilizers, and restoration of degraded lands. In this perspective paper, it is proposed that restoration of degraded lands can contribute considerably to improved soil CH4 sink strength by retrieving/conserving abundance and assortment of efficient methanotrophic communities. We believe that this report can assist in identifying future experimental directions to the relationships between landuse changes, methane-assimilating microbial communities and soil CH4 sinks. The exploitation of microbial communities other than methanotrophs can contribute significantly to the global CH4 sink potential and can add value in mitigating the CH4 problems.

  2. Constraining the sources of CH4 emissions during past abrupt climate change using CH4 triple isotopes mass balance from the ice core records

    NASA Astrophysics Data System (ADS)

    Dyonisius, M.; Petrenko, V. V.; Smith, A. W.; Hmiel, B.; Beck, J.; Seth, B.; Bock, M.; Hua, Q.; Yang, B.; Harth, C. M.; Beaudette, R.; Lee, J.; Erhardt, T.; Schmitt, J.; Brook, E.; Weiss, R. F.; Fischer, H.; Severinghaus, J. P.

    2017-12-01

    Methane (CH4) is the third most important greenhouse gas in the atmosphere after water vapor and CO2. Understanding how the natural CH4 budget has changed in response to changing climate in the past can provide insights on the sensitivity of the natural CH4 emissions to the current anthropogenic warming. CH4 isotopes (Δ14CH4, δ13C-CH4, and δD-CH4) from ice cores can be used to fingerprint the sources of CH4 increases in the past. We have successfully extracted 6 large volume (>1000kg) ice core samples from Taylor Glacier, Antarctica spanning the Oldest Dryas-Bølling transition ( 14.7ka) - the first abrupt warming and CH4 rise since the Last Glacial Maximum. Among the CH4 isotopes, our Δ 14CH4 data are unique in their ability to unambiguously distinguish between "old" CH4 sources (e.g. marine clathrate, geologic sources, old permafrost) and "modern" CH4 sources (e.g. tropical and boreal wetlands). Our Δ14CH4 data unambiguously rule out marine clathrate and old permafrost as the sources of the abrupt CH4 rise. Preliminary CH4 stable isotopes box modeling combined with interpolar CH4 concentration gradient from existing ice core records suggest that tropical wetlands were the dominant driver for the Oldest Dryas-Bølling CH4 rise.

  3. Deployment and early results from the CanSIM (Canadian Solar Spectral Irradiance Meter) network

    NASA Astrophysics Data System (ADS)

    Tatsiankou, Viktar; Hinzer, Karin; Schriemer, Henry; McVey-White, Patrick; Beal, Richard

    2017-09-01

    Three of seven stations have been deployed as part of the Canadian Solar Spectral Irradiance (CanSIM) network situated in Ottawa, Varennes and Egbert to measure long term spectral variation of the direct normal (DNI) and global horizontal irradiances (GHI) across the country. Every station is equipped with a solar tracker, SolarSIM-D2+, SolarSIM-G+, and SR20 pyranometer, reporting the spectral DNI, GHI, diffuse horizontal irradiance (DHI) and aerosol optical depth in the 280-4000 nm range, broadband DNI, GHI, and DHI, atmospheric total column ozone and water vapour amounts. The spectral GHI as measured by the SolarSIM-G+ was within 5% as compared to EKO MS-700 spectroradiometer in 350-1050 nm range on 17 March 2017. The difference in the GHI as reported by SolarSIM-G+ and SR20 pyranometer from all stations was within 2% on 14 April 2017. Furthermore, on this day, the daily GHI sum for the Ottawa, Varennes, and Egbert stations was 7.01, 6.95, and 7.11 kWh/m2, respectively, while the daily DNI sum was 10.65, 10.86, 10.04 kWh/m2, respectively.

  4. A Mechanistical Study on the Formation of Dimethyl Ether (CH3OCH3) and Ethanol (CH3CH2OH) in Methanol-containing Ices and Implications for the Chemistry of Star-forming Regions

    NASA Astrophysics Data System (ADS)

    Bergantini, Alexandre; Góbi, Sándor; Abplanalp, Matthew J.; Kaiser, Ralf I.

    2018-01-01

    The underlying formation mechanisms of complex organic molecules (COMs)—in particular, structural isomers—in the interstellar medium (ISM) are largely elusive. Here, we report new experimental findings on the role of methanol (CH3OH) and methane (CH4) ices in the synthesis of two C2H6O isomers upon interaction with ionizing radiation: ethanol (CH3CH2OH) and dimethyl ether (CH3OCH3). The present study reproduces the interstellar abundance ratios of both species with ethanol to dimethyl ether branching ratios of (2.33 ± 0.14):1 suggesting that methanol and methane represents the key precursor to both isomers within interstellar ices. Exploiting isotopic labeling combined with reflectron time-of-flight mass spectrometry (Re-TOF-MS) after isomer selective vacuum ultra-violet (VUV) photoionization of the neutral molecules, we also determine the formation mechanisms of both isomers via radical–radical recombination versus carbene (CH2) insertion with the former pathway being predominant. Formation routes to higher molecular weight reaction products such as ethylene glycol (HOCH2CH2OH), dimethyl peroxide (CH3OOCH3), and methoxymethanol (CH3OCH2OH) are discussed briefly as well.

  5. Key role of amino acid residues in the dimerization and catalytic activation of the autolysin LytA, an important virulence factor in Streptococcus pneumoniae.

    PubMed

    Romero, Patricia; López, Rubens; García, Ernesto

    2007-06-15

    LytA, the main autolysin of Streptococcus pneumoniae, was the first member of the bacterial N-acetylmuramoyl-l-alanine amidase (NAM-amidase) family of proteins to be well characterized. This autolysin degrades the peptidoglycan bonds of pneumococcal cell walls after anchoring to the choline residues of the cell wall teichoic acids via its choline-binding module (ChBM). The latter is composed of seven repeats (ChBRs) of approximately 20 amino acid residues. The translation product of the lytA gene is the low-activity E-form of LytA (a monomer), which can be "converted" (activated) in vitro by choline into the fully active C-form at low temperature. The C-form is a homodimer with a boomerang-like shape. To study the structural requirements for the monomer-to-dimer modification and to clarify whether "conversion" is synonymous with dimerization, the biochemical consequences of replacing four key amino acid residues of ChBR6 and ChBR7 (the repeats involved in dimer formation) were determined. The results obtained with a collection of 21 mutated NAM-amidases indicate that Ile-315 is a key amino acid residue in both LytA activity and folding. Amino acids with a marginal position in the solenoid structure of the ChBM were of minor influence in dimer stability; neither the size, polarity, nor aromatic nature of the replacement amino acids affected LytA activity. In contrast, truncated proteins were drastically impaired in their activity and conversion capacity. The results indicate that dimerization and conversion are different processes, but they do not answer the questions of whether conversion can only be achieved after a dimer formation step.

  6. A model immunization programme to control Japanese encephalitis in Viet Nam.

    PubMed

    Yen, Nguyen Thu; Liu, Wei; Hanh, Hoang Duc; Chang, Na Yoon; Duong, Tran Nhu; Gibbons, Robert V; Marks, Florian; Thu, Nghiem Anh; Hong, Nguyen Minh; Park, Jin Kyung; Tuan, Pham Anh; Nisalak, Ananda; Clemens, John D; Xu, Zhi-Yi

    2015-03-01

    In Viet Nam, an inactivated, mouse brain-derived vaccine for Japanese encephalitis (JE) has been given exclusively to ≤ 5 years old children in 3 paediatric doses since 1997. However, JE incidence remained high, especially among children aged 5-9 years. We conducted a model JE immunization programme to assess the feasibility and impact of JE vaccine administered to 1-9 year(s) children in 3 standard-dose regimen: paediatric doses for children aged <3 years and adult doses for those aged ≥ 3 years. Of the targeted children, 96.2% were immunized with ≥ 2 doses of the vaccine. Compared to the national immunization programme, JE incidence rate declined sharply in districts with the model programme (11.32 to 0.87 per 100,000 in pre-versus post-vaccination period). The rate of reduction was most significant in the 5-9 years age-group. We recommend a policy change to include 5-9 years old children in the catch-up immunization campaign and administer a 4th dose to those aged 5-9 years, who had received 3 doses of the vaccine during the first 2-3 years of life.

  7. A Model Immunization Programme to Control Japanese Encephalitis in Viet Nam

    PubMed Central

    Yen, Nguyen Thu; Hanh, Hoang Duc; Chang, Na Yoon; Duong, Tran Nhu; Gibbons, Robert V.; Marks, Florian; Thu, Nghiem Anh; Hong, Nguyen Minh; Park, Jin Kyung; Tuan, Pham Anh; Nisalak, Ananda; Clemens, John D.; Xu, Zhi-yi

    2015-01-01

    ABSTRACT In Viet Nam, an inactivated, mouse brain-derived vaccine for Japanese encephalitis (JE) has been given exclusively to ≤5 years old children in 3 paediatric doses since 1997. However, JE incidence remained high, especially among children aged 5-9 years. We conducted a model JE immunization programme to assess the feasibility and impact of JE vaccine administered to 1-9 year(s) children in 3 standard-dose regimen: paediatric doses for children aged <3 years and adult doses for those aged ≥3 years. Of the targeted children, 96.2% were immunized with ≥2 doses of the vaccine. Compared to the national immunization programme, JE incidence rate declined sharply in districts with the model programme (11.32 to 0.87 per 100,000 in pre-versus post-vaccination period). The rate of reduction was most significant in the 5-9 years age-group. We recommend a policy change to include 5-9 years old children in the catch-up immunization campaign and administer a 4th dose to those aged 5-9 years, who had received 3 doses of the vaccine during the first 2-3 years of life. PMID:25995736

  8. Interannual Variability and Trends of CH4, CO and OH Using the Computationally-Efficient CH4-CO-OH (ECCOH) Module

    NASA Technical Reports Server (NTRS)

    Elshorbany, Yasin F.; Duncan, Bryan N.; Strode, Sarah A.; Wang, James S.; Kouatchou, Jules

    2015-01-01

    Methane (CH4) is the second most important anthropogenic greenhouse gas (GHG). Its 100-year global warming potential (GWP) is 34 times larger than that for carbon dioxide. The 100-year integrated GWPof CH4 is sensitive to changes in hydroxyl radical (OH) levels.Oxidation of CH4 and carbon monoxide (CO) by OH is the main loss process, thus affecting the oxidizing capacity of the atmosphere and contributing to the global ozone background. Limitations of using archived, monthly OH fields for studies of methane's and COs evolution are that feedbacks of the CH4-CO-OH system on methane, CO and OH are not captured. In this study, we employ the computationally Efficient CH4-CO-OH (ECCOH) module (Elshorbany et al., 2015) to investigate the nonlinear feedbacks of the CH4-CO-OH system on the interannual variability and trends of the CH4, CO, OH system.

  9. Inverse Modeling of Surface CH4 and δ13C-CH4 Measurements to Understand Recent Trends in Global Methane Emissions

    NASA Astrophysics Data System (ADS)

    Karmakar, S.; Butenhoff, C. L.; Rice, A. L.; Lofdahl, D. B.; Khalil, A. K.

    2016-12-01

    Methane (CH4) is the second most important greenhouse gas with a radiative forcing of 0.97 W/m2 including both direct and indirect effects and a global warming potential of 28 over a 100-year time horizon. Unlike CO2 whose rate of growth in the atmosphere has remained positive and increased in recent decades, the behavior of atmospheric methane is considerably more complex and is much less understood on account of the spatiotemporal variability of its emissions which include biogenic (e.g. wetlands, ruminants, rice agriculture), thermogenic (fossil fuels), and pyrogenic (i.e. biomass burning) sources. After sustained growth during most of the 20th century, the CH4 growth rate declined falling from 15 ppbv/yr during the 1980s to 6 ppbv/yr in the 1990s to near-zero and even negative values in the early 2000s. With some surprise however, the growth rate rebounded in 2007 and has been on average 6 ppbv/yr during the past 10 years. During this same period the 13CH4/12CH4 ratio of atmospheric CH4 also declined suggesting the recent CH4 growth was caused by an increase in 13CH4-depleted biogenic emissions. Here, we provide additional insight into the recent behavior of atmospheric methane by performing a global three-dimensional Bayesian inversion of surface CH4 and 13CH4/12CH4 ratios over the period 1985-2015 using NOAA Global Monitoring Division (GMD) CH4 measurements and the GEOS-Chem chemical-transport model (CTM) at a horizontal grid resolution of 2ox2.5o. The use of the 3-D model allows us to exploit spatial patterns in the global CH4 and 13CH4/12CH4 fields that provide additional constraints on the retrieval of the time-dependent CH4 fluxes. This work follows up on our previous CH4 inversion where we used a 4ox5o horizontal grid for GEOS-Chem to retrieve fluxes from 1985 to 2009. At higher resolution more information is extracted from the observations due to improved model skill and a smaller number of stations aggregated within model grid cells. This increases the

  10. Thermal decomposition and oxidation of CH3OH.

    PubMed

    Lee, Pei-Fang; Matsui, Hiroyuki; Xu, Ding-Wei; Wang, Niann-Shiah

    2013-01-24

    Thermal decomposition of CH(3)OH diluted in Ar has been studied by monitoring H atoms behind reflected shock waves of 100 ppm CH(3)OH + Ar. The total decomposition rate k(1) for CH(3)OH + M → products obtained in this study is expressed as, ln(k(1)/cm(3) molecule(-1) s(-1)) = -(14.81 ± 1.22) - (38.86 ± 1.82) × 10(3)/T, over 1359-1644 K. The present result on k(1) is indicated to be substantially smaller than the extrapolation of the most of the previous experimental data but consistent with the published theoretical results [Faraday Discuss. 2002, 119, 191-205 and J. Phys. Chem. A 2007, 111, 3932-3950]. Oxidation of CH(3)OH has been studied also by monitoring H atoms behind shock waves of (0.35-100) ppm CH(3)OH + (100-400) ppm O(2) + Ar. For the low concentration CH(3)OH (below 10 ppm) + O(2) mixtures, the initial concentration of CH(3)OH is evaluated by comparing evolutions of H atoms in the same concentration of CH(3)OH with addition of 300 ppm H(2) diluted in Ar. The branching fraction for CH(3)OH + Ar → (1)CH(2) + H(2)O + Ar has been quantitatively evaluated from this comparative measurements with using recent experimental result on the yield of H atoms in the reaction of (1,3)CH(2) + O(2) [J. Phys. Chem. A 2012, 116, 9245-9254]; i.e., the branching fraction for the above reaction is evaluated as, φ(1a) = 0.20 ± 0.04 at T = 1880-2050 K, in the 1.3 and 3.5 ppm CH(3)OH + 100 ppm O(2) samples. An extended reaction mechanism for the pyrolysis and oxidation of CH(3)OH is constructed based on the results of the present study combined with the oxidation mechanism of natural gas [GRI-Mech 3.0]; evolution of H atoms can be predicted very well with this new reaction scheme over a wide concentration range for the pyrolysis (0.36-100 ppm CH(3)OH), and oxidation (0.36-100 ppm CH(3)OH + 100/400 ppm O(2)) of methanol.

  11. Liver disease in Viet Nam: screening, surveillance, management and education: a 5-year plan and call to action.

    PubMed

    Gish, Robert G; Bui, Tam D; Nguyen, Chuc T K; Nguyen, Duc T; Tran, Huy V; Tran, Diem M T; Trinh, Huy N

    2012-02-01

    Despite a high prevalence of liver disease in Viet Nam, there has been no nationwide approach to the disease and no systematic screening of at-risk individuals. Risk factors include chronic hepatitis B (estimated prevalence of 12%), chronic hepatitis C (at least 2% prevalence), and heavy consumption of alcohol among men. This combination of factors has resulted in liver cancer being the most common cause of cancer death in Viet Nam. There is a general lack of understanding by both the general public and health-care providers about the major risk to health that liver disease represents. We report here the initial steps taken as part of a comprehensive approach to liver disease that will ultimately include nationwide education for health-care providers, health educators, and the public; expansion of nationwide screening for hepatitis B and C followed by hepatitis B virus vaccination or treatment of chronic hepatitis B and/or hepatitis C; education about alcoholic liver disease; long-term surveillance for liver cancer; reduction of infection transmission related to medical, commercial, and personal re-use of contaminated needles, syringes, sharp instruments, razors, and inadequately sterilized medical equipment; and ongoing collection and analysis of data about the prevalence of all forms of liver disease and the results of the expanded screening, vaccination, and treatment programs. We report the beginning results of our pilot hepatitis B screening program. We believe that this comprehensive nationwide approach could substantially reduce the morbidity and mortality from liver disease and greatly lessen the burden in terms of both lives lost and health-care costs. © 2011 Journal of Gastroenterology and Hepatology Foundation and Blackwell Publishing Asia Pty Ltd.

  12. Subsoil methanogenesis as source of stem CH4 emission in upland forest trees: preferential CH4 transport via the root system?

    NASA Astrophysics Data System (ADS)

    Maier, M.; Machacova, K.; Urban, O.; Friederike, L.

    2016-12-01

    Quantifying and understanding green house gas fluxes in natural soil-plant-atmosphere systems are crucial to predicting global climate change. Wetland species or trees at waterlogged sites are known to emit large amounts of CH4. Yet upland forest soils are regarded as CH4 sinks and tree species like upland European beech (Fagus sylvatica, L.) are assumed not to emit CH4. We studied the soil-atmosphere and stem-atmosphere fluxes of CH4, and soil gas profiles at two upland beech forest sites in Central Europe. Soil was a net CH4 sink at both. Unusually there was one beech tree with substantial CH4 emissions that were higher than the CH4 sink of the soil. The soil gas profile at this tree indicated CH4 production at a soil depth >0.3 m, despite the net uptake of CH4 observed at the soil surface adjacent to the tree. Field soil assessment showed strong redoximorphic color patterns in the adjacent soil. We think that there is a transport link between the soil and stem via the root system representing a preferential transport mechanism for CH4 despite the fact that beech roots usually do not bear aerenchyma. The gas transport process , either via dissolved CH4 in the xylem water or in the root gas phase, is not yet clear. The observed CH4 stem emissions represent an important CH4flux in this ecosystem, und thus should be considered in future research. AcknowledgementThis research was financially supported by the Czech Academy of Sciences and the German Academic Exchange Service within the project "Methane (CH4) and nitrous oxide (N2O) emissions from Fagus sylvatica trees" (DAAD-15-03), National Programme for Sustainability I (LO1415) and project DFG (MA 5826/2-1). We would like to thank Marek Jakubik, Katerina Svobodova, Sinikka Paulus, Ellen Halaburt and Sally Haddad for technical support.

  13. Direct formation of (CH sub 3 ) sub 2 HSiCl from silicon and CH sub 3 Cl

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

    Magrini, K.A.; Falconer, J.L.; Koel, B.E.

    1989-07-13

    A Cu-catalyzed reaction procedure was found for the selective formation of dimethylchlorosilane ((CH{sub 3}){sub 2}HSiCl) from the direct reaction of CH{sub 3}Cl with solid Si. The new procedure is a two-step process. A Cu/Si sample is prepared by evaporating Cu onto clean polycrystalline Si under ultrahigh vacuum, and the Cu/Si surface is first activated by exposure to 10% HSiCl{sub 3}/CH{sub 3}Cl at 598 K. After the HSiCl{sub 3}CH{sub 3}Cl mixture is evacuated from the reactor, the activated Cu/Si surface is reacted in fresh CH{sub 3}Cl. For low surface concentrations of Cu, the partially hydrogenated silane, (CH{sub 3}){sub 2}HSiCl, is selectivelymore » produced. Trichlorosilane was also found to activate polycrystalline Si (in the absence of Cu) for production of highly chlorinated methylchlorosilanes at a much higher rate than on the Cu/Si surface but with poor selectively to (CH{sub 3}){sub 2}HSiCl. All reactions are carried out at atmospheric pressure in a reactor that is attached to an ultrahigh-vacuum chamber. This allows surface analysis of Auger electron spectroscopy, which detected SiCl{sub x} on reacted surfaces. These SiCl{sub x} sites, which appear necessary for methylchlorosilane formation, are apparently formed during activation by HSiCl{sub 3}.« less

  14. Photodissociation of the CH3O and CH3S radical molecules: An ab initio electronic structure study

    PubMed Central

    Bouallagui, A.; Zanchet, A.; Yazidi, O.; Jaïdane, N.; Bañares, L.; Senent, M.L.; García-Vela, A.

    2018-01-01

    The electronic states and the spin-orbit couplings between them involved in the photodissociation process of the radical molecules CH3X, CH3X → CH3 + X(X = O, S), taking place after the Ā(2A1) ← X̄(2E) transition, have been investigated using highly correlated ab initio techniques. A two-dimensional representation of both the potential-energy surfaces (PESs) and the couplings is generated. This description includes the C-X dissociative mode and the CH3 umbrella mode. Spin-orbit effects are found to play a relevant role on the shape of the excited state potential-energy surfaces, particularly in the CH3S case where the spin-orbit couplings are more than twice more intense than in CH3O. The potential surfaces and couplings reported here for the present set of electronic states allow for the first complete description of the above photodissociation process. The different photodissociation mechanisms are analyzed and discussed in the light of the results obtained. PMID:29143005

  15. A DFT-Elucidated Comparison of the Solution-Phase and SAM Electrochemical Properties of Short-Chain Mercaptoalkylferrocenes: Synthetic and Spectroscopic Aspects, and the Structure of Fc-CH2CH2-S-S-CH2CH2-Fc.

    PubMed

    Lewtak, Jan P; Landman, Marilé; Fernández, Israel; Swarts, Jannie C

    2016-03-07

    Facile synthetic procedures to synthesize a series of difficult-to-obtain mercaptoalkylferrocenes, namely, Fc(CH2)nSH, where n = 1 (1), 2 (2), 3 (3), or 4 (4) and Fc = Fe(η(5)-C5H5)(η(5)-C5H4), are reported. Dimerization of 1-4 to the corresponding disulfides 19-22 was observed in air. Dimer 20 (Z = 2) crystallized in the triclinic space group P1̅. Dimers 20-22 could be reduced back to the original Fc(CH2)nSH derivatives with LiAlH4 in refluxing tetrahydrofuran. Density functional theory (DFT) calculations showed that the highest occupied molecular orbital of 1-4 lies exclusively on the ferrocenyl group implying that the electrochemical oxidation observed at ca. -15 < Epa < 76 mV versus FcH/FcH(+) involves exclusively an Fe(II) to Fe(III) process. Further DFT calculations showed this one-electron oxidation is followed by proton loss on the thiol group to generate a radical, Fc(CH2)nS(•), with spin density mainly located on the sulfur. Rapid exothermic dimerization leads to the observed dimers, Fc(CH2)n-S-S-(CH 2)nFc. Reduction of the ferrocenium groups on the dimer occurs at potentials that still showed the ferrocenyl group ΔE = Epa,monomer - Epc,dimer ≤ 78 mV, indicating that the redox properties of the ferrocenyl group on the mercaptans are very similar to those of the dimer. (1)H NMR measurements showed that, like ferrocenyl oxidation, the resonance position of the sulfhydryl proton, SH, and others, are dependent on -(CH2)n- chain length. Self-assembled monolayers (SAMs) on gold were generated to investigate the electrochemical behavior of 1-4 in the absence of diffusion. Under these conditions, ΔE approached 0 mV for the longer chain derivatives at slow scan rates. The surface-bound ferrocenyl group of the metal-thioether, Fc(CH2)n -S-Au, is oxidized at approximately equal potentials as the equivalent CH2Cl2-dissolved ferrocenyl species 1-4. Surface coverage by the SAMs is dependent on alkyl chain length with the largest coverage obtained for 4, while

  16. Infrared spectroscopy of solid normal hydrogen doped with CH3F and O2 at 4.2 K: CH3F:O2 complex and CH3F migration

    NASA Astrophysics Data System (ADS)

    Abouaf-Marguin, L.; Vasserot, A.-M.

    2011-04-01

    Double doping of solid normal hydrogen with CH3F and O2 at about 4.2 K gives evidence of (ortho-H2)n:CH3F clusters and of O2:CH3F complex formation. FTIR analysis of the time evolution of the spectra in the region of the v3 C-F stretching mode indicates that these clusters behave very differently from (ortho-H2)n:H2O clusters. The main point is the observed migration of CH3F molecules in solid para-H2 at 4.2 K which differs from that of H2O under identical experimental conditions. This is confirmed by an increase over time of the integrated intensity of the CH3F:O2 complex with a rate constant K = 2.7(2) . 10-4 s-1.

  17. InChIKey collision resistance: an experimental testing

    PubMed Central

    2012-01-01

    InChIKey is a 27-character compacted (hashed) version of InChI which is intended for Internet and database searching/indexing and is based on an SHA-256 hash of the InChI character string. The first block of InChIKey encodes molecular skeleton while the second block represents various kinds of isomerism (stereo, tautomeric, etc.). InChIKey is designed to be a nearly unique substitute for the parent InChI. However, a single InChIKey may occasionally map to two or more InChI strings (collision). The appearance of collision itself does not compromise the signature as collision-free hashing is impossible; the only viable approach is to set and keep a reasonable level of collision resistance which is sufficient for typical applications. We tested, in computational experiments, how well the real-life InChIKey collision resistance corresponds to the theoretical estimates expected by design. For this purpose, we analyzed the statistical characteristics of InChIKey for datasets of variable size in comparison to the theoretical statistical frequencies. For the relatively short second block, an exhaustive direct testing was performed. We computed and compared to theory the numbers of collisions for the stereoisomers of Spongistatin I (using the whole set of 67,108,864 isomers and its subsets). For the longer first block, we generated, using custom-made software, InChIKeys for more than 3 × 1010 chemical structures. The statistical behavior of this block was tested by comparison of experimental and theoretical frequencies for the various four-letter sequences which may appear in the first block body. From the results of our computational experiments we conclude that the observed characteristics of InChIKey collision resistance are in good agreement with theoretical expectations. PMID:23256896

  18. InChIKey collision resistance: an experimental testing.

    PubMed

    Pletnev, Igor; Erin, Andrey; McNaught, Alan; Blinov, Kirill; Tchekhovskoi, Dmitrii; Heller, Steve

    2012-12-20

    InChIKey is a 27-character compacted (hashed) version of InChI which is intended for Internet and database searching/indexing and is based on an SHA-256 hash of the InChI character string. The first block of InChIKey encodes molecular skeleton while the second block represents various kinds of isomerism (stereo, tautomeric, etc.). InChIKey is designed to be a nearly unique substitute for the parent InChI. However, a single InChIKey may occasionally map to two or more InChI strings (collision). The appearance of collision itself does not compromise the signature as collision-free hashing is impossible; the only viable approach is to set and keep a reasonable level of collision resistance which is sufficient for typical applications.We tested, in computational experiments, how well the real-life InChIKey collision resistance corresponds to the theoretical estimates expected by design. For this purpose, we analyzed the statistical characteristics of InChIKey for datasets of variable size in comparison to the theoretical statistical frequencies. For the relatively short second block, an exhaustive direct testing was performed. We computed and compared to theory the numbers of collisions for the stereoisomers of Spongistatin I (using the whole set of 67,108,864 isomers and its subsets). For the longer first block, we generated, using custom-made software, InChIKeys for more than 3 × 1010 chemical structures. The statistical behavior of this block was tested by comparison of experimental and theoretical frequencies for the various four-letter sequences which may appear in the first block body.From the results of our computational experiments we conclude that the observed characteristics of InChIKey collision resistance are in good agreement with theoretical expectations.

  19. High Resolution CH4 Emissions and Dissolved CH4 Measurements Elucidate Surface Gas Exchange Processes in Toolik Lake, Arctic Alaska

    NASA Astrophysics Data System (ADS)

    Del Sontro, T.; Sollberger, S.; Kling, G. W.; Shaver, G. R.; Eugster, W.

    2013-12-01

    Approximately 14% of the Alaskan North Slope is covered in lakes of various sizes and depths. Diffusive carbon emissions (CH4 and CO2) from these lakes offset the tundra sink by ~20 %, but the offset would substantially increase if ebullitive CH4 emissions were also considered. Ultimately, arctic lake CH4 emissions are not insignificant in the global CH4 budget and their contribution is bound to increase due to impacts from climate change. Here we present high resolution CH4 emission data as measured via eddy covariance and a Los Gatos gas analyzer during the ice free period from Toolik Lake, a deep (20 m) Arctic lake located on the Alaskan North Slope, over the last few summers. Emissions are relatively low (< 25 mg CH4 m-2 d-1) with little variation over the summer. Diurnal variations regularly occur, however, with up to 3 times higher fluxes at night. Gas exchange is a relatively difficult process to estimate, but is normally done so as the product of the CH4 gradient across the air-water interface and the gas transfer velocity, k. Typically, k is determined based on the turbulence on the water side of the interface, which is most commonly approximated by wind speed; however, it has become increasingly apparent that this assumption does not remain valid across all water bodies. Dissolved CH4 profiles in Toolik revealed a subsurface peak in CH4 at the thermocline of up to 3 times as much CH4 as in the surface water. We hypothesize that convective mixing at night due to cooling surface waters brings the subsurface CH4 to the surface and causes the higher night fluxes. In addition to high resolution flux emission estimates, we also acquired high resolution data for dissolved CH4 in surface waters of Toolik Lake during the last two summers using a CH4 equilibrator system connected to a Los Gatos gas analyzer. Thus, having both the flux and the CH4 gradient across the air-water interface measured directly, we can calculate k and investigate the processes influencing

  20. Atmospheric nitrogen deposition budget in a subtropical hydroelectric reservoir (Nam Theun II case study, Lao PDR)

    NASA Astrophysics Data System (ADS)

    Adon, Marcellin; Galy-Lacaux, Corinne; Serça, Dominique; Guerin, Frederic; Guedant, Pierre; Vonghamsao, Axay; Rode, Wanidaporn

    2016-04-01

    With 490 km² at full level of operation, Nam Theun 2 (NT2) is one of the largest hydro-reservoir in South East Asia. NT2 is a trans-basin hydropower project that diverts water from the Nam Theun river (a Mekong tributary) to the Xe Ban Fai river (another Mekong tributary). Atmospheric deposition is an important source of nitrogen (N), and it has been shown that excessive fluxes of N from the atmosphere has resulted in eutrophication of many coastal waters. A large fraction of atmospheric N input is in the form of inorganic N. This study presents an estimation of the atmospheric inorganic nitrogen budget into the NT2 hydroelectric reservoir based on a two-year monitoring (July 2010 to July 2012) including gas concentrations and precipitation. Dry deposition fluxes are calculated from monthly mean surface measurements of NH3, HNO3 and NO2 concentrations (passive samplers) together with simulated deposition velocities, and wet deposition fluxes from NH4+ and NO3- concentrations in single event rain samples (automated rain sampler). Annual rainfall amount was 2500 and 3160 mm for the two years. The average nitrogen deposition flux is estimated at 1.13 kgN.ha-1.yr-1 from dry processes and 5.52 kgN.ha-1.yr-1 from wet ones, i.e., an average annual total nitrogen flux of 6.6 kgN.ha-1.yr-1 deposited into the NT2 reservoir. The wet deposition contributes to 83% of the total N deposition. The nitrogen deposition budget has been also calculated over the rain tropical forest surrounding the reservoir. Due to higher dry deposition velocities above forested ecosystems, gaseous dry deposition flux is estimated at 4.0 kgN.ha-1.yr-1 leading to a total nitrogen deposition about 9.5 kgN.ha-1.yr-1. This result will be compared to nitrogen deposition in the African equatorial forested ecosystems in the framework of the IDAF program (IGAC-DEBITS-AFrica).

  1. Global Inverse Modeling of CH4 and δ13C-CH4 Measurements to Understand Recent Trends in Methane Emissions

    NASA Astrophysics Data System (ADS)

    Karmakar, S.; Butenhoff, C. L.; Rice, A. L.; Khalil, A. K.

    2017-12-01

    Methane (CH4) is the second most important greenhouse gas with a radiative forcing of 0.97 W/m2 including both direct and indirect effects and a global warming potential of 28 over a 100-year time horizon. After a decades-long period of decline beginning in the 1980s, the methane growth rate rebounded in 2007 for reasons that are of current debate. During this same growth period atmospheric methane became less enriched in the 13CH4 isotope suggesting the recent CH4 growth was caused by an increase in 13CH4-depleted biogenic emissions. Recent papers have attributed this growth to increasing emissions from wetlands, rice agriculture, and ruminants. In this work we provide additional insight into the recent behavior of atmospheric methane and global wetland emissions by performing a three-dimensional Bayesian inversion of surface CH4 and 13CH4/12CH4 ratios using NOAA Global Monitoring Division (GMD) "event-level" CH4 measurements and the GEOS-Chem chemical-transport model (CTM) at a horizontal grid resolution of 2ox2.5o. The spatial pattern of wetland emissions was prescribed using soil moisture and temperature from GEOS-5 meteorology fields and soil carbon pools from the Lund-Potsdam-Jena global vegetation model. In order to reduce the aggregation error caused by a potentially flawed distribution and to account for isotopic measurements that indicate northern high latitude wetlands are isotopically depleted in 13CH4 relative to tropical wetlands we separated our pattern into three latitudinal bands (90-30°N, 30°N-0, 0-90°S). Our preliminary results support previous claims that the recent increase in atmospheric methane is driven by increases in biogenic CH4 emissions. We find that while wetland emissions from northern high latitudes (90-30°N) remained relatively constant during this time, southern hemisphere wetland emissions rebounded from a decade-long decline and began to rise again in 2007 and have remained elevated to the present. Emissions from rice

  2. ChIP-nexus: a novel ChIP-exo protocol for improved detection of in vivo transcription factor binding footprints

    PubMed Central

    He, Qiye; Johnston, Jeff; Zeitlinger, Julia

    2014-01-01

    Understanding how eukaryotic enhancers are bound and regulated by specific combinations of transcription factors is still a major challenge. To better map transcription factor binding genome-wide at nucleotide resolution in vivo, we have developed a robust ChIP-exo protocol called ChIP experiments with nucleotide resolution through exonuclease, unique barcode and single ligation (ChIP-nexus), which utilizes an efficient DNA self-circularization step during library preparation. Application of ChIP-nexus to four proteins—human TBP and Drosophila NFkB, Twist and Max— demonstrates that it outperforms existing ChIP protocols in resolution and specificity, pinpoints relevant binding sites within enhancers containing multiple binding motifs and allows the analysis of in vivo binding specificities. Notably, we show that Max frequently interacts with DNA sequences next to its motif, and that this binding pattern correlates with local DNA sequence features such as DNA shape. ChIP-nexus will be broadly applicable to studying in vivo transcription factor binding specificity and its relationship to cis-regulatory changes in humans and model organisms. PMID:25751057

  3. Abundance and prevalence of Aedes aegypti immatures and relationships with household water storage in rural areas in southern Viet Nam.

    PubMed

    Nguyen, Le Anh P; Clements, Archie C A; Jeffery, Jason A L; Yen, Nguyen Thi; Nam, Vu Sinh; Vaughan, Gregory; Shinkfield, Ramon; Kutcher, Simon C; Gatton, Michelle L; Kay, Brian H; Ryan, Peter A

    2011-06-01

    Since 2000, the Government of Viet Nam has committed to provide rural communities with increased access to safe water through a variety of household water supply schemes (wells, ferrocement tanks and jars) and piped water schemes. One possible, unintended consequence of these schemes is the concomitant increase in water containers that may serve as habitats for dengue mosquito immatures, principally Aedes aegypti. To assess these possible impacts we undertook detailed household surveys of Ae. aegypti immatures, water storage containers and various socioeconomic factors in three rural communes in southern Viet Nam. Positive relationships between the numbers of household water storage containers and the prevalence and abundance of Ae. aegypti immatures were found. Overall, water storage containers accounted for 92-97% and 93-96% of the standing crops of III/IV instars and pupae, respectively. Interestingly, households with higher socioeconomic levels had significantly higher numbers of water storage containers and therefore greater risk of Ae. aegypti infestation. Even after provision of piped water to houses, householders continued to store water in containers and there was no observed decrease in water storage container abundance in these houses, compared to those that relied entirely on stored water. These findings highlight the householders' concerns about the limited availability of water and their strong behavoural patterns associated with storage of water. We conclude that household water storage container availability is a major risk factor for infestation with Ae. aegypti immatures, and that recent investment in rural water supply infrastructure are unlikely to mitigate this risk, at least in the short term.

  4. Where "Sign Language Studies" Has Led Us in Forty Years: Opening High School and University Education for Deaf People in Viet Nam through Sign Language Analysis, Teaching, and Interpretation

    ERIC Educational Resources Information Center

    Woodward, James; Hoa, Nguyen Thi

    2012-01-01

    This paper discusses how the Nippon Foundation-funded project "Opening University Education to Deaf People in Viet Nam through Sign Language Analysis, Teaching, and Interpretation," also known as the Dong Nai Deaf Education Project, has been implemented through sign language studies from 2000 through 2012. This project has provided deaf…

  5. Additional Value of CH4 Measurement in a Combined 13C/H2 Lactose Malabsorption Breath Test: A Retrospective Analysis

    PubMed Central

    Houben, Els; De Preter, Vicky; Billen, Jaak; Van Ranst, Marc; Verbeke, Kristin

    2015-01-01

    The lactose hydrogen breath test is a commonly used, non-invasive method for the detection of lactose malabsorption and is based on an abnormal increase in breath hydrogen (H2) excretion after an oral dose of lactose. We use a combined 13C/H2 lactose breath test that measures breath 13CO2 as a measure of lactose digestion in addition to H2 and that has a better sensitivity and specificity than the standard test. The present retrospective study evaluated the results of 1051 13C/H2 lactose breath tests to assess the impact on the diagnostic accuracy of measuring breath CH4 in addition to H2 and 13CO2. Based on the 13C/H2 breath test, 314 patients were diagnosed with lactase deficiency, 138 with lactose malabsorption or small bowel bacterial overgrowth (SIBO), and 599 with normal lactose digestion. Additional measurement of CH4 further improved the accuracy of the test as 16% subjects with normal lactose digestion and no H2-excretion were found to excrete CH4. These subjects should have been classified as subjects with lactose malabsorption or SIBO. In conclusion, measuring CH4-concentrations has an added value to the 13C/H2 breath test to identify methanogenic subjects with lactose malabsorption or SIBO. PMID:26371034

  6. Electron-spin-resonance studies of 12CH3F + , 13CH3F + , and 12CH2DF + in neon matrices at 4 K: Comparison with theoretical calculations

    NASA Astrophysics Data System (ADS)

    Knight, Lon B., Jr.; Gregory, Brian W.; Hill, Devon W.; Arrington, C. A.; Momose, Takamasa; Shida, Tadamasa

    1991-01-01

    Various isotopic forms of the methyl fluoride cation 12CH3F+, 13CH3F+, and 12CH2DF+ have been generated by photoionization at 16.8 eV and separately by electron bombardment at 50 eV. The first electron-spin-resonance (ESR) results are reported for this radical cation which was isolated in neon matrices at 4 K. The measured A tensors or nuclear hyperfine parameters were compared with the results obtained from various computational approaches. Surprising observations were the large amounts of spin density on the methyl group, especially the hydrogen atoms, and the extreme differences in the deuterated spectra compared to the nondeuterated case. The presence of a single D atom apparently acts to prevent dynamic Jahn-Teller averaging which makes the methyl hydrogens equivalent on the ESR time scale. Such a dramatic Jahn-Teller effect has been previously observed for the similar methane cations CH+4 and CH2D+2. The magnetic parameters for CH2DF+ in neon at 4 K are gX=2.0032(5), gY=2.0106(8), and gZ=2.0120(5); for H: AX = 483(1), AY=476(1), and AZ=483(1) MHz; for D: ‖AX‖=5.0(3), ‖AY‖<3, and ‖AZ‖=7.1(3) MHz; for 19F : AX=965(1), AY=-130(2), and AZ=-166(1) MHz. For CH3F+, the g tensor and 19F A tensor were similar to those above but the H atoms were equivalent with values of AX=317(1), AY=323(2), and AZ=312 MHz.

  7. Recent Developments in C-H Activation for Materials Science in the Center for Selective C-H Activation.

    PubMed

    Zhang, Junxiang; Kang, Lauren J; Parker, Timothy C; Blakey, Simon B; Luscombe, Christine K; Marder, Seth R

    2018-04-16

    Abstract : Organic electronics is a rapidly growing field driven in large part by the synthesis of ∏-conjugated molecules and polymers. Traditional aryl cross-coupling reactions such as the Stille and Suzuki have been used extensively in the synthesis of ∏-conjugated molecules and polymers, but the synthesis of intermediates necessary for traditional cross-couplings can include multiple steps with toxic and hazardous reagents. Direct arylation through C-H bond activation has the potential to reduce the number of steps and hazards while being more atom-economical. Within the Center for Selective C-H Functionalization (CCHF), we have been developing C-H activation methodology for the synthesis of ∏-conjugated materials of interest, including direct arylation of difficult-to-functionalize electron acceptor intermediates and living polymerization of ∏-conjugated polymers through C-H activation.

  8. Calculations on the orientation of the CH fragment in Co 3(CO) 9(μ 3-CH): Implications for metal surfaces

    NASA Astrophysics Data System (ADS)

    DeKock, Roger L.; Fehlner, Thomas P.

    1982-07-01

    A series of molecular orbital calculations using the Fenske-Hall method have been carried out on Co 3(CO) 9(μ 3-CH), in which the orientation of the CH fragment is varied with respect to the triangular plane of the three Co atoms. The calculations show that the energy differences between the orbitals that are predominantly CH in character are affected very little by the orientation of the CH fragment. These calculated differences are Δ(2 σ-1 σ)≅7 eV and Δ(1 π-1 σ)≅ 10.5 eV. The calculated splitting of the degenerate 1π orbitals for geometries with tilted CH fragments never amounted to more than 0.46 eV. Mixing of CH orbitals into the predominantly Co 3d manifold was extensive in all of the calculations. These calculations provide no support for the interpretation of energy loss and photoemission electron spectroscopy experiments in terms of CH fragments that are tilted with respect to the metal surface, but such an interpretation cannot be eliminated due to the diffuse nature of the spectral bands in the photoemission experiments.

  9. Study design and the estimation of the size of key populations at risk of HIV: lessons from Viet Nam.

    PubMed

    Safarnejad, Ali; Groot, Wim; Pavlova, Milena

    2018-01-30

    Estimation of the size of populations at risk of HIV is a key activity in the surveillance of the HIV epidemic. The existing framework for considering future research needs may provide decision-makers with a basis for a fair process of deciding on the methods of the estimation of the size of key populations at risk of HIV. This study explores the extent to which stakeholders involved with population size estimation agree with this framework, and thus, the study updates the framework. We conducted 16 in-depth interviews with key informants from city and provincial governments, NGOs, research institutes, and the community of people at risk of HIV. Transcripts were analyzed and reviewed for significant statements pertaining to criteria. Variations and agreement around criteria were analyzed, and emerging criteria were validated against the existing framework. Eleven themes emerged which are relevant to the estimation of the size of populations at risk of HIV in Viet Nam. Findings on missing criteria, inclusive participation, community perspectives and conflicting weight and direction of criteria provide insights for an improved framework for the prioritization of population size estimation methods. The findings suggest that the exclusion of community members from decision-making on population size estimation methods in Viet Nam may affect the validity, use, and efficiency of the evidence generated. However, a wider group of decision-makers, including community members among others, may introduce diverse definitions, weight and direction of criteria. Although findings here may not apply to every country with a transitioning economy or to every emerging epidemic, the principles of fair decision-making, value of community participation in decision-making and the expected challenges faced, merit consideration in every situation.

  10. Episiotomy rate in Vietnamese-born women in Australia: support for a change in obstetric practice in Viet Nam.

    PubMed

    Trinh, Anh T; Khambalia, Amina; Ampt, Amanda; Morris, Jonathan M; Roberts, Christine L

    2013-05-01

    To describe the use of episiotomy among Vietnamese-born women in Australia, including risk factors for, and pregnancy outcomes associated with, episiotomy. This population-based, retrospective cohort study included data on 598 305 singleton, term (i.e. ≥ 37 weeks' gestation) and vertex-presenting vaginal births between 2001 and 2010. Data were obtained from linked, validated, population-level birth and hospitalization data sets. Contingency tables and multivariate analysis were used to compare risk factors and pregnancy outcomes in women who did or did not have an episiotomy. The episiotomy rate in 12 208 Vietnamese-born women was 29.9%, compared with 15.1% in Australian-born women. Among Vietnamese-born women, those who had an episiotomy were significantly more likely than those who did not to be primiparous, give birth in a private hospital, have induced labour or undergo instrumental delivery. In these women, having an episiotomy was associated with postpartum haemorrhage (adjusted odds ratio, aOR: 1.26; 95% confidence interval, CI: 1.08-1.46) and postnatal hospitalization for more than 4 days (aOR: 1.14; 95% CI: 1.00-1.29). Among multiparous women only, episiotomy was positively associated with a third- or fourth-degree perineal tear (aOR: 2.00; 95% CI: 1.31-3.06); in contrast, among primiparous women the association was negative (aOR: 0.47; 95% CI: 0.37-0.60). Episiotomy was performed in far fewer Vietnamese-born women giving birth in Australia than in Viet Nam, where more than 85% undergo the procedure, and was not associated with adverse outcomes. A lower episiotomy rate should be achievable in Viet Nam.

  11. EIA models and capacity building in Viet Nam: an analysis of development aid programs

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

    Doberstein, Brent

    2004-04-01

    There has been a decided lack of empirical research examining development aid agencies as 'agents of change' in environmental impact assessment (EIA) systems in developing countries, particularly research examining the model of environmental planning practice promoted by aid agencies as part of capacity building. This paper briefly traces a conceptual framework of EIA, then introduces the concept of 'EIA capacity building'. Using Viet Nam as a case study, the paper then outlines the empirical results of the research, focusing on the extent to which aid agency capacity-building programs promoted a Technical vs. Planning Model of EIA and on the coherencemore » of capacity-building efforts across all aid programs. A discussion follows, where research results are interpreted within the Vietnamese context, and implications of research results are identified for three main groups of actors. The paper concludes by calling for development aid agencies to reconceptualise EIA capacity building as an opportunity to transform developing countries' development planning processes.« less

  12. ChIP-PaM: an algorithm to identify protein-DNA interaction using ChIP-Seq data.

    PubMed

    Wu, Song; Wang, Jianmin; Zhao, Wei; Pounds, Stanley; Cheng, Cheng

    2010-06-03

    ChIP-Seq is a powerful tool for identifying the interaction between genomic regulators and their bound DNAs, especially for locating transcription factor binding sites. However, high cost and high rate of false discovery of transcription factor binding sites identified from ChIP-Seq data significantly limit its application. Here we report a new algorithm, ChIP-PaM, for identifying transcription factor target regions in ChIP-Seq datasets. This algorithm makes full use of a protein-DNA binding pattern by capitalizing on three lines of evidence: 1) the tag count modelling at the peak position, 2) pattern matching of a specific tag count distribution, and 3) motif searching along the genome. A novel data-based two-step eFDR procedure is proposed to integrate the three lines of evidence to determine significantly enriched regions. Our algorithm requires no technical controls and efficiently discriminates falsely enriched regions from regions enriched by true transcription factor (TF) binding on the basis of ChIP-Seq data only. An analysis of real genomic data is presented to demonstrate our method. In a comparison with other existing methods, we found that our algorithm provides more accurate binding site discovery while maintaining comparable statistical power.

  13. The ChArMEx database

    NASA Astrophysics Data System (ADS)

    Ferré, Hélène; Belmahfoud, Nizar; Boichard, Jean-Luc; Brissebrat, Guillaume; Cloché, Sophie; Descloitres, Jacques; Fleury, Laurence; Focsa, Loredana; Henriot, Nicolas; Mière, Arnaud; Ramage, Karim; Vermeulen, Anne; Boulanger, Damien

    2015-04-01

    The Chemistry-Aerosol Mediterranean Experiment (ChArMEx, http://charmex.lsce.ipsl.fr/) aims at a scientific assessment of the present and future state of the atmospheric environment in the Mediterranean Basin, and of its impacts on the regional climate, air quality, and marine biogeochemistry. The project includes long term monitoring of environmental parameters , intensive field campaigns, use of satellite data and modelling studies. Therefore ChARMEx scientists produce and need to access a wide diversity of data. In this context, the objective of the database task is to organize data management, distribution system and services, such as facilitating the exchange of information and stimulating the collaboration between researchers within the ChArMEx community, and beyond. The database relies on a strong collaboration between ICARE, IPSL and OMP data centers and has been set up in the framework of the Mediterranean Integrated Studies at Regional And Locals Scales (MISTRALS) program data portal. ChArMEx data, either produced or used by the project, are documented and accessible through the database website: http://mistrals.sedoo.fr/ChArMEx. The website offers the usual but user-friendly functionalities: data catalog, user registration procedure, search tool to select and access data... The metadata (data description) are standardized, and comply with international standards (ISO 19115-19139; INSPIRE European Directive; Global Change Master Directory Thesaurus). A Digital Object Identifier (DOI) assignement procedure allows to automatically register the datasets, in order to make them easier to access, cite, reuse and verify. At present, the ChArMEx database contains about 120 datasets, including more than 80 in situ datasets (2012, 2013 and 2014 summer campaigns, background monitoring station of Ersa...), 25 model output sets (dust model intercomparison, MEDCORDEX scenarios...), a high resolution emission inventory over the Mediterranean... Many in situ datasets

  14. The CH/π hydrogen bond: Implication in chemistry

    NASA Astrophysics Data System (ADS)

    Nishio, M.

    2012-06-01

    The CH/π hydrogen bond is the weakest extreme of hydrogen bonds that occurs between a soft acid CH and a soft base π-system. Implication in chemistry of the CH/π hydrogen bond includes issues of conformation, crystal packing, and specificity in host/guest complexes. The result obtained by analyzing the Cambridge Structural Database is reviewed. The peculiar axial preference of isopropyl group in α-phellandrene and folded conformation of levopimaric acid have been explained in terms of the CH/π hydrogen bond, by high-level ab initio MO calculations. Implication of the CH/π hydrogen bond in structural biology is also discussed, briefly.

  15. The products of the thermal decomposition of CH{sub 3}CHO

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

    Vasiliou, AnGayle; National Renewable Energy Laboratory, 1617 Cole Blvd., Golden, Colorado 80401; Piech, Krzysztof M.

    2011-07-07

    We have used a heated 2 cm x 1 mm SiC microtubular ({mu}tubular) reactor to decompose acetaldehyde: CH{sub 3}CHO +{Delta}{yields} products. Thermal decomposition is followed at pressures of 75-150 Torr and at temperatures up to 1675 K, conditions that correspond to residence times of roughly 50-100 {mu}s in the {mu}tubular reactor. The acetaldehyde decomposition products are identified by two independent techniques: vacuum ultraviolet photoionization mass spectroscopy (PIMS) and infrared (IR) absorption spectroscopy after isolation in a cryogenic matrix. Besides CH{sub 3}CHO, we have studied three isotopologues, CH{sub 3}CDO, CD{sub 3}CHO, and CD{sub 3}CDO. We have identified the thermal decomposition productsmore » CH{sub 3} (PIMS), CO (IR, PIMS), H (PIMS), H{sub 2} (PIMS), CH{sub 2}CO (IR, PIMS), CH{sub 2}=CHOH (IR, PIMS), H{sub 2}O (IR, PIMS), and HC{identical_to}CH (IR, PIMS). Plausible evidence has been found to support the idea that there are at least three different thermal decomposition pathways for CH{sub 3}CHO; namely, radical decomposition: CH{sub 3}CHO +{Delta}{yields} CH{sub 3}+[HCO]{yields} CH{sub 3}+ H + CO; elimination: CH{sub 3}CHO +{Delta}{yields} H{sub 2}+ CH{sub 2}=C=O; isomerization/elimination: CH{sub 3}CHO +{Delta}{yields}[CH{sub 2}=CH-OH]{yields} HC{identical_to}CH + H{sub 2}O. An interesting result is that both PIMS and IR spectroscopy show compelling evidence for the participation of vinylidene, CH{sub 2}=C:, as an intermediate in the decomposition of vinyl alcohol: CH{sub 2}=CH-OH +{Delta}{yields}[CH{sub 2}=C:]+ H{sub 2}O {yields} HC{identical_to}CH + H{sub 2}O.« less

  16. Electrochemical Cobalt-Catalyzed C-H Activation.

    PubMed

    Sauermann, Nicolas; Meyer, Tjark H; Ackermann, Lutz

    2018-06-19

    Carbon-heteroatom bonds represent omnipresent structural motifs of the vast majority of functionalized materials and bioactive compounds. C-H activation has emerged as arguably the most efficient strategy to construct C-Het bonds. Despite of major advances, these C-H transformations were largely dominated by precious transition metal catalysts, in combination with stoichiometric, toxic metal oxidants. Herein, we discuss the recent evolution of cobalt-catalyzed C-H activations that enable C-Het formations with electricity as the sole sustainable oxidant until May 2018. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Ice core δD(CH4) record precludes marine hydrate CH4 emissions at the onset of Dansgaard-Oeschger events

    NASA Astrophysics Data System (ADS)

    Bock, M.; Schmitt, J.; Möller, L.; Spahni, R.; Blunier, T.; Fischer, H.

    2010-12-01

    Air enclosures in polar ice cores represent the only direct paleoatmospheric archive (besides firn air) and show that atmospheric CH4 concentrations changed in concert with northern hemisphere temperature during both glacial/interglacial transitions as well as rapid climate changes (Dansgaard-Oeschger events). For stadials and interstadials during Marine Isotope Stage 3 concentration jumps of 100 - 200 ppbv within a few decades are observed. A concentration gradient with higher values in the northern versus the southern hemisphere during warm stages was reconstructed from ice core methane data from Greenland and Antarctica. This gradient indicates additional methane emissions during warm periods located in the northern hemisphere. However, the underlying processes for these changes are still not well understood. With tropical and boreal wetlands, biomass burning, thermokarst lakes, ruminants, termites, UV-induced emissions from organic matter and marine gas hydrates all contributing to the natural atmospheric CH4 level, an unambiguous source attribution remains difficult. Also changes in the methane sinks can modify the tropospheric CH4 budget, as trace gases like volatile organic compounds are competing for the major reactant - the OH radical. Additionally, the changing global atmospheric methane concentration itself feeds back on its lifetime. Together with the CH4 interhemispheric gradient, stable hydrogen and carbon isotopic studies on methane (δD(CH4) and δ13CH4) in ice cores allow to constrain individual CH4 source/sink changes. Here we present clear evidence from the North Greenland Ice Core Project ice core based on the hydrogen isotopic composition of methane δD(CH4) that clathrates did not cause atmospheric methane concentration to rise at the onset of Dansgaard-Oeschger (DO) events 7 and 8 (34 - 41 kilo years before present), however, we can not exclude that they played a minor role during and at the end of an interstadial. Box modeling supports

  18. l48_ghi_10km

    Science.gov Websites

    information on the solar resource potential for the 48 Contiguous United States. This data provides monthly latitude and longitude, or about 10 km in size. This data was developed using the State University of New images from geostationary weather satellites, daily snow cover data, and monthly averages of atmospheric

  19. Rate Coefficient Measurements of the Reaction CH3 + O2 = CH3O + O

    NASA Technical Reports Server (NTRS)

    Hwang, S. M.; Ryu, Si-Ok; DeWitt, K. J.; Rabinowitz, M. J.

    1999-01-01

    Rate coefficients for the reaction CH3 + O2 = CH3O + O were measured behind reflected shock waves in a series of lean CH4-O2-Ar mixtures using hydroxyl and methyl radical diagnostics. The rate coefficients are well represented by an Arrhenius expression given as k = (1.60(sup +0.67, sub -0.47 ) x 10(exp 13) e(-15813 +/- 587 K/T)/cubic cm.mol.s. This expression, which is valid in the temperature range 1575-1822 K, supports the downward trend in the rate coefficients that has been reported in recent determinations. All measurements to date, including the present study, have been to some extent affected by secondary reactions. The complications due to secondary reactions, choice of thermochemical data, and shock-boundary layer interactions that affect the determination of the rate coefficients are examined.

  20. Rate Coefficient Measurements of the Reaction CH3+O2+CH3O+O

    NASA Technical Reports Server (NTRS)

    Hwang, S. M.; Ryu, Si-Ok; DeWitt, K. J.; Rabinowitz, M. J.

    1999-01-01

    Rate coefficients for the reaction CH3 + O2 = CH3O + O were measured behind reflected shock waves in a series of lean CH4-O2-Ar mixtures using hydroxyl and methyl radical diagnostics. The rate coefficients are well represented by an Arrhenius expression given as k = (1.60(sup +0.67, -0.47)) X 10(exp 13) exp(- 15813 +/- 587 K/T)cc/mol s. This expression, which is valid in the temperature range 1575-1822 K, supports the downward trend in the rate coefficients that has been reported in recent determinations. All measurements to date, including the present study, have been to some extent affected by secondary reactions. The complications due to secondary reactions, choice of thermochemical data, and shock-boundary layer interactions that affect the determination of the rate coefficients are examined.

  1. Tropospheric photooxidation of CF3CH2CHO and CF3(CH2)2CHO initiated by Cl atoms and OH radicals

    NASA Astrophysics Data System (ADS)

    Antiñolo, M.; Jiménez, E.; Notario, A.; Martínez, E.; Albaladejo, J.

    2009-11-01

    The absolute rate coefficients for the tropospheric reactions of chlorine (Cl) atoms and hydroxyl (OH) radicals with CF3CH2CHO and CF3(CH2)2CHO were measured as a function of temperature (263-371 K) and pressure (50-215 Torr of He) by pulsed UV laser photolysis techniques. Vacuum UV resonance fluorescence was employed to detect and monitor the time evolution of Cl atoms. Laser induced fluorescence was used in this work as a detection of OH radicals as a function of reaction time. No pressure dependence of the bimolecular rate coefficients, kCl and kOH, was found at all temperatures. At room temperature kCl and kOH were (in 10-11 cm3 molecule-1 s-1): kCl(CF3CH2CHO) = (1.55±0.53); kCl(CF3(CH2)2CHO) = (3.39±1.38); kOH(CF3CH2CHO) = (0.259±0.050); kOH(CF3(CH2)2CHO) = (1.28±0.24). A slightly negative temperature dependence of kCl was observed for CF3CH2CHO and CF3(CH2)2CHO, and kOH(CF3CH2CHO). In contrast, kOH(CF3(CH2)2CHO) did not exhibit a temperature dependence in the studied ranged. Arrhenius expressions for these reactions were: kCl(CF3CH2CHO) =(4.4±1.0) × 10-11 exp{-(316±68)/T} cm3 molecule-1 s-1, kCl(CF3(CH2)2CHO) = (2.9±0.7) × 10-10 exp{-625±80)/T} cm3 molecule-1 s-1, kOH(CF3CH2CHO) = (7.8±2.2) × 10-12 exp{-(314±90)/T} cm3 molecule-1 s-1. The atmospheric impact of the homogeneous removal by OH radicals and Cl atoms of these fluorinated aldehydes is discussed in terms of the global atmospheric lifetimes, taking into account different degradation pathways. The calculated lifetimes show that atmospheric oxidation of CF3(CH2)xCHO are globally dominated by OH radicals, however reactions initiated by Cl atoms can act as a source of free radicals at dawn in the troposphere.

  2. Tropospheric photooxidation of CF3CH2CHO and CF3(CH2)2CHO initiated by Cl atoms and OH radicals

    NASA Astrophysics Data System (ADS)

    Antiñolo, M.; Jiménez, E.; Notario, A.; Martínez, E.; Albaladejo, J.

    2010-02-01

    The absolute rate coefficients for the tropospheric reactions of chlorine (Cl) atoms and hydroxyl (OH) radicals with CF3CH2CHO and CF3(CH2)2CHO were measured as a function of temperature (263-371 K) and pressure (50-215 Torr of He) by pulsed UV laser photolysis techniques. Vacuum UV resonance fluorescence was employed to detect and monitor the time evolution of Cl atoms. Laser induced fluorescence was used in this work for the detection of OH radicals as a function of reaction time. No pressure dependence of the bimolecular rate coefficients, kCl and kOH, was found at all temperatures. At room temperature kCl and kOH were (in 10-11 cm3 molecule-1 s-1): kCl(CF3CH2CHO) = (1.55±0.53); kCl(CF3(CH2)2CHO) = (3.39±1.38); kCl(CF3CH2CHO) = (0.259±0.050); kCl(CF3(CH2)2CHO) = (1.28±0.24). A slightly positive temperature dependence of kCl was observed for CF3CH2CHO and CF3(CH2)2CHO, and kOH(CF3CH2CHO). In contrast, kOH(CF3(CH2)2CHO) did not exhibit a temperature dependence over the range investigated. Arrhenius expressions for these reactions were: kCl(CF3CH2CHO) = (4.4±1.0)×10-11 exp{-(316±68)/T} cm3 molecule-1 s-1 kCl(CF3(CH2)2CHO) = (2.9±0.7)×10-10 exp{-(625±80)/T} cm3 molecule-1 s-1 kOH(CF3CH2CHO) = (7.8±2.2)×10-12 exp{-(314±90)/T} cm3 molecule-1 s-1 The atmospheric impact of the homogeneous removal by OH radicals and Cl atoms of these fluorinated aldehydes is discussed in terms of the global atmospheric lifetimes, taking into account different degradation pathways. The calculated lifetimes show that atmospheric oxidation of CF3(CH2)x CHO are globally dominated by OH radicals, however reactions initiated by Cl atoms can act as a source of free radicals at dawn in the troposphere.

  3. Shipboard measurements and modeling of the distribution of CH4 and 13CH4 in the western Pacific

    NASA Astrophysics Data System (ADS)

    Bromley, T.; Allan, W.; Martin, R.; Mikaloff Fletcher, S. E.; Lowe, D. C.; Struthers, H.; Moss, R.

    2012-02-01

    We present observations of methane (CH4) mixing ratio and 13C/12C isotopic ratios in CH4 (δ13C) data from a collaborative shipboard project using bulk carrier ships sailing between Nelson, New Zealand, and Osaka, Japan, in the western Pacific Ocean. Measurements of the CH4 mixing ratio and δ13C in CH4were obtained from large clean-air samples collected in each 2.5° to 5° of latitude between 30°S and 30°N on eight voyages from 2004 to 2007. The data show large variations in CH4 mixing ratio in the tropical western Pacific, and data analysis suggests that these large variations are related to the positions and strengths of the South Pacific Convergence Zone and the Intertropical Convergence Zone, with variability in the sources playing a much smaller role. These measurements are compared with results from a modified version of the Unified Model (UMeth) general circulation model along two transects, one similar to the ship transects and another 18.75° to the east. Although UMeth was run to a steady state with the same sources and sinks each year, the gradient structures varied considerably from year to year, supporting our conclusion that variability in transport is a major driver for the observed variations in CH4. Simulations forced with an idealized representation of the El Niño-Southern Oscillation (ENSO) suggest that a large component of the observed variability in latitudinal gradients of CH4 and its δ13C arises from intrinsic variability in the climate system that does not occur on ENSO time scales.

  4. The ChIP-Seq tools and web server: a resource for analyzing ChIP-seq and other types of genomic data.

    PubMed

    Ambrosini, Giovanna; Dreos, René; Kumar, Sunil; Bucher, Philipp

    2016-11-18

    ChIP-seq and related high-throughput chromatin profilig assays generate ever increasing volumes of highly valuable biological data. To make sense out of it, biologists need versatile, efficient and user-friendly tools for access, visualization and itegrative analysis of such data. Here we present the ChIP-Seq command line tools and web server, implementing basic algorithms for ChIP-seq data analysis starting with a read alignment file. The tools are optimized for memory-efficiency and speed thus allowing for processing of large data volumes on inexpensive hardware. The web interface provides access to a large database of public data. The ChIP-Seq tools have a modular and interoperable design in that the output from one application can serve as input to another one. Complex and innovative tasks can thus be achieved by running several tools in a cascade. The various ChIP-Seq command line tools and web services either complement or compare favorably to related bioinformatics resources in terms of computational efficiency, ease of access to public data and interoperability with other web-based tools. The ChIP-Seq server is accessible at http://ccg.vital-it.ch/chipseq/ .

  5. Anomalous torsional tripling in the ν9 and ν10 CH3-deformation modes of ethane 12CH313CH3

    NASA Astrophysics Data System (ADS)

    Lattanzi, F.; di Lauro, C.

    2017-12-01

    We have investigated the anomalous torsional behavior in the coupled ν9 and ν10 vibrational fundamentals of 12CH313CH3, both states exhibiting a splitting into three components, instead of two, only in those rotational levels which are very close to resonance. We conclude that the intrinsic additional splitting, which occurs in the E-torsional components, for these two vibrational states is too small to be detected in the high resolution infrared spectrum, but it is substantively enhanced by their coupling. It is shown that this effect requires the simultaneous action of torsion independent operators, such as Fermi-type and z-Coriolis, not allowed in the more symmetric isotopologue 12CH312CH3, and torsion dependent operators, such as torsional-Coriolis, connecting the two vibrational states. Our conclusions lead to a simple model for the coupling of ν9 and ν10, with effective Fermi-type matrix elements W for the A-torsional components, and W ± w for the two pairs of E-torsional components. This causes the additional splitting in the E-pairs. This model is consistent with the mechanism causing the Coriolis-dependent decrease of the A-E torsional splitting in degenerate vibrational states. Exploratory calculations were performed making use of results from a normal mode analysis, showing that the effects predictable by the proposed model are of the correct order of magnitude compared to the observed features, with coupling parameter values reasonably consistent with those determined by the least squares fit of the observed transition wavenumbers.

  6. Isotopic signatures of anthropogenic CH4 sources in Alberta, Canada

    NASA Astrophysics Data System (ADS)

    Lopez, M.; Sherwood, O. A.; Dlugokencky, E. J.; Kessler, R.; Giroux, L.; Worthy, D. E. J.

    2017-09-01

    A mobile system was used for continuous ambient measurements of stable CH4 isotopes (12CH4 and 13CH4) and ethane (C2H6). This system was used during a winter mobile campaign to investigate the CH4 isotopic signatures and the C2H6/CH4 ratios of the main anthropogenic sources of CH4 in the Canadian province of Alberta. Individual signatures were derived from δ13CH4 and C2H6 measurements in plumes arriving from identifiable single sources. Methane emissions from beef cattle feedlots (n = 2) and landfill (n = 1) had δ13CH4 signatures of -66.7 ± 2.4‰ and -55.3 ± 0.2‰, respectively. The CH4 emissions associated with the oil or gas industry had distinct δ13CH4 signatures, depending on the formation process. Emissions from oil storage tanks (n = 5) had δ13CH4 signatures ranging from -54.9 ± 2.9‰ to -60.6 ± 0.6‰ and non-detectable C2H6, characteristic of secondary microbial methanogenesis in oil-bearing reservoirs. In contrast, CH4 emissions associated with natural gas facilities (n = 8) had δ13CH4 signatures ranging from -41.7 ± 0.7‰ to -49.7 ± 0.7‰ and C2H6/CH4 molar ratios of 0.10 for raw natural gas to 0.04 for processed/refined natural gas, consistent with thermogenic origins. These isotopic signatures and C2H6/CH4 ratios have been used for source discrimination in the weekly atmospheric measurements of stable CH4 isotopes over a two-month winter period at the Lac La Biche (LLB) measurement station, located in Alberta, approximately 200 km northeast of Edmonton. The average signature of -59.5 ± 1.4‰ observed at LLB is likely associated with transport of air after passing over oil industry sources located south of the station.

  7. A Comparison Between Heliosat-2 and Artificial Neural Network Methods for Global Horizontal Irradiance Retrievals over Desert Environments

    NASA Astrophysics Data System (ADS)

    Ghedira, H.; Eissa, Y.

    2012-12-01

    Global horizontal irradiance (GHI) retrievals at the surface of any given location could be used for preliminary solar resource assessments. More accurately, the direct normal irradiance (DNI) and diffuse horizontal irradiance (DHI) are also required to estimate the global tilt irradiance, mainly used for fixed flat plate collectors. Two different satellite-based models for solar irradiance retrievals have been applied over the desert environment of the United Arab Emirates (UAE). Both models employ channels of the SEVIRI instrument, onboard the geostationary satellite Meteosat Second Generation, as their main inputs. The satellite images used in this study have a temporal resolution of 15-min and a spatial resolution of 3-km. The objective of this study is to compare between the GHI retrieved using the Heliosat-2 method and an artificial neural network (ANN) ensemble method over the UAE. The high-resolution visible channel of SEVIRI is used in the Heliosat-2 method to derive the cloud index. The cloud index is then used to compute the cloud transmission, while the cloud-free GHI is computed from the Linke turbidity factor. The product of the cloud transmission and the cloud-free GHI denotes the estimated GHI. A constant underestimation is observed in the estimated GHI over the dataset available in the UAE. Therefore, the cloud-free DHI equation in the model was recalibrated to fix the bias. After recalibration, results over the UAE show a root mean square error (RMSE) value of 10.1% and a mean bias error (MBE) of -0.5%. As for the ANN approach, six thermal channels of SEVIRI were used to estimate the DHI and the total optical depth of the atmosphere (δ). An ensemble approach is employed to obtain a better generalizability of the results, as opposed to using one single weak network. The DNI is then computed from the estimated δ using the Beer-Bouguer-Lambert law. The GHI is computed from the DNI and DHI estimates. The RMSE for the estimated GHI obtained over an

  8. ChAT-ChR2-EYFP mice have enhanced motor endurance but show deficits in attention and several additional cognitive domains.

    PubMed

    Kolisnyk, Benjamin; Guzman, Monica S; Raulic, Sanda; Fan, Jue; Magalhães, Ana C; Feng, Guoping; Gros, Robert; Prado, Vania F; Prado, Marco A M

    2013-06-19

    Acetylcholine (ACh) is an important neuromodulator in the nervous system implicated in many forms of cognitive and motor processing. Recent studies have used bacterial artificial chromosome (BAC) transgenic mice expressing channelrhodopsin-2 (ChR2) protein under the control of the choline acetyltransferase (ChAT) promoter (ChAT-ChR2-EYFP) to dissect cholinergic circuit connectivity and function using optogenetic approaches. We report that a mouse line used for this purpose also carries several copies of the vesicular acetylcholine transporter gene (VAChT), which leads to overexpression of functional VAChT and consequently increased cholinergic tone. We demonstrate that these mice have marked improvement in motor endurance. However, they also present severe cognitive deficits, including attention deficits and dysfunction in working memory and spatial memory. These results suggest that increased VAChT expression may disrupt critical steps in information processing. Our studies demonstrate that ChAT-ChR2-EYFP mice show altered cholinergic tone that fundamentally differentiates them from wild-type mice.

  9. CH4 production via CO2 reduction in a temperate bog - A source of (C-13)-depleted CH4

    NASA Technical Reports Server (NTRS)

    Lansdown, J. M.; Quay, P. D.; King, S. L.

    1992-01-01

    The paper reports measurements, taken over two annual cycles, of the flux and delta(C-13) of CH4 released from an acidic peat bog located in the foothills of the Cascade Range in Washington state, U.S. Measurements of the rate of aceticlastic methanogenesis and CO2 reduction in peat soil, using (C-14)-labeled acetate and sodium bicarbonate, show that acetate was not an important CH4 precursor and that CO2 reduction could account for all of the CH4 production. The in situ kinetic isotope effect for CO2 reduction, calculated using the delta-(C-13) of soil water CO2 and CH4 flux, was 0.932 +/- 0.007.

  10. ChLae1 and ChVel1 Regulate T-toxin Production, Virulence, Oxidative Stress Response, and Development of the Maize Pathogen Cochliobolus heterostrophus

    PubMed Central

    Wu, Dongliang; Oide, Shinichi; Zhang, Ning; Choi, May Yee; Turgeon, B. Gillian

    2012-01-01

    LaeA and VeA coordinate secondary metabolism and differentiation in response to light signals in Aspergillus spp. Their orthologs, ChLae1 and ChVel1, were identified in the maize pathogen Cochliobolus heterostrophus, known to produce a wealth of secondary metabolites, including the host selective toxin, T-toxin. Produced by race T, T-toxin promotes high virulence to maize carrying Texas male sterile cytoplasm (T-cms). T-toxin production is significantly increased in the dark in wild type (WT), whereas Chvel1 and Chlae1 mutant toxin levels are much reduced in the dark compared to WT. Correspondingly, expression of T-toxin biosynthetic genes (Tox1) is up-regulated in the dark in WT, while dark-induced expression is much reduced/minimal in Chvel1 and Chlae1 mutants. Toxin production and Tox1 gene expression are increased in ChVEL1 overexpression (OE) strains grown in the dark and in ChLAE1 strains grown in either light or dark, compared to WT. These observations establish ChLae1 and ChVel1 as the first factors known to regulate host selective toxin production. Virulence of Chlae1 and Chvel1 mutants and OE strains is altered on both T-cms and normal cytoplasm maize, indicating that both T-toxin mediated super virulence and basic pathogenic ability are affected. Deletion of ChLAE1 or ChVEL1 reduces tolerance to H2O2. Expression of CAT3, one of the three catalase genes, is reduced in the Chvel1 mutant. Chlae1 and Chvel1 mutants also show decreased aerial hyphal growth, increased asexual sporulation and female sterility. ChLAE1 OE strains are female sterile, while ChVEL1 OE strains are more fertile than WT. ChLae1 and ChVel1 repress expression of 1,8-dihydroxynaphthalene (DHN) melanin biosynthesis genes, and, accordingly, melanization is enhanced in Chlae1 and Chvel1 mutants, and reduced in OE strains. Thus, ChLae1 and ChVel1 positively regulate T-toxin biosynthesis, pathogenicity and super virulence, oxidative stress responses, sexual development, and aerial hyphal

  11. Catastrophic flood and forest cover change in the Huong river basin, central Viet Nam: a gap between common perceptions and facts.

    PubMed

    Tran, Phong; Marincioni, Fausto; Shaw, Rajib

    2010-11-01

    Recent catastrophic floods in Viet Nam have been increasingly linked to land use and forest cover change in the uplands. Despite the doubts that many scientists have expressed on such nexus, this common view prompted both positive forest protection/reforestation programs and often-unwarranted blame on upland communities for their forest management practices. This study discusses the disparity between public perceptions and scientific evidences relating the causes of catastrophic floods. The former was drawn on the results of a questionnaire and focus groups discussions with key informants of different mountainous communities, whereas the latter was based on GIS and remote sensing analysis of land cover change, including a statistical analysis of hydro-meteorological data of the Huong river basin in Viet Nam. Results indicate that there is a gap between the common beliefs and the actual relationship between the forest cover change and catastrophic floods. Undeniably, the studied areas showed significant changes in land cover over the period 1989-2008, yet, 71% of the variance of catastrophic flood level in the downstream areas appeared related to variance in rainfall. Evidences from this study showed that the overall increasing trends of catastrophic flooding in the Huong river basin was mainly due to climate variability and to the development of main roads and dyke infrastructures in the lowlands. Forest management policies and programs, shaped on the common assumption that forest degradation in the upland is the main cause of catastrophic flood in the downstream areas, should be reassessed to avoid unnecessary strain on upland people. Copyright 2010 Elsevier Ltd. All rights reserved.

  12. Use of eschar swabbing for the molecular diagnosis and genotyping of Orientia tsutsugamushi causing scrub typhus in Quang Nam province, Vietnam.

    PubMed

    Le Viet, Nhiem; Laroche, Maureen; Thi Pham, Hoa L; Viet, Nho L; Mediannikov, Oleg; Raoult, Didier; Parola, Philippe

    2017-02-01

    Scrub typhus is a rickettsiosis which is caused by Orientia tsutsugamushi and occurs throughout the Asia-Pacific region. Molecular diagnosis of rickettsioses using eschar swabs has recently emerged, and may be very useful for the diagnosis of these diseases in tropical settings. Quantitative polymerase chain reaction (qPCR) was used to detect O. tsutsugamushi DNA in whole blood and eschar swab specimens of 67 patients who were clinically suspected of scrub typhus in Quang Nam province, Vietnam. Among the 20 patients for whom both eschar and whole blood were obtained, 17 (85%) of the eschar specimens and 5 (25%) of the whole blood specimens tested positive for O. tsutsugamushi. Genetic analysis of the 56-kDa TSA gene sequences demonstrated that the 14 sequences obtained in this study, including 12 eschar swabs and 2 whole blood specimens, were related to 4 groups: Karp, Kawasaki, Gilliam (JG-v and TG-v) and TA716. The majority (9/14; 64.4%) of contemporary O. tsutsugamushi genotypes in Quang Nam province were related to the Karp group. These results suggest that polyclonal antigen pools used for serological testing in the future should contain at least Karp, Kawasaki, Gilliam and TA716 antigens for Vietnamese patients, as well as patients who have traveled to Vietnam. qPCR after eschar swabbing should be considered for molecular diagnosis of scrub typhus in endemic patients as well as in travelers, since it is easy to perform and appears very useful for the rapid detection of Orientia tsutsugamushi in the early phase of infection.

  13. Use of eschar swabbing for the molecular diagnosis and genotyping of Orientia tsutsugamushi causing scrub typhus in Quang Nam province, Vietnam

    PubMed Central

    Le Viet, Nhiem; Laroche, Maureen; Thi Pham, Hoa L.; Viet, Nho L.; Mediannikov, Oleg; Raoult, Didier; Parola, Philippe

    2017-01-01

    Background Scrub typhus is a rickettsiosis which is caused by Orientia tsutsugamushi and occurs throughout the Asia-Pacific region. Molecular diagnosis of rickettsioses using eschar swabs has recently emerged, and may be very useful for the diagnosis of these diseases in tropical settings. Methodology/Principal findings Quantitative polymerase chain reaction (qPCR) was used to detect O. tsutsugamushi DNA in whole blood and eschar swab specimens of 67 patients who were clinically suspected of scrub typhus in Quang Nam province, Vietnam. Among the 20 patients for whom both eschar and whole blood were obtained, 17 (85%) of the eschar specimens and 5 (25%) of the whole blood specimens tested positive for O. tsutsugamushi. Genetic analysis of the 56-kDa TSA gene sequences demonstrated that the 14 sequences obtained in this study, including 12 eschar swabs and 2 whole blood specimens, were related to 4 groups: Karp, Kawasaki, Gilliam (JG-v and TG-v) and TA716. The majority (9/14; 64.4%) of contemporary O. tsutsugamushi genotypes in Quang Nam province were related to the Karp group. Conclusions These results suggest that polyclonal antigen pools used for serological testing in the future should contain at least Karp, Kawasaki, Gilliam and TA716 antigens for Vietnamese patients, as well as patients who have traveled to Vietnam. qPCR after eschar swabbing should be considered for molecular diagnosis of scrub typhus in endemic patients as well as in travelers, since it is easy to perform and appears very useful for the rapid detection of Orientia tsutsugamushi in the early phase of infection. PMID:28241043

  14. Infrared absorption of 1-chloro-2-methyl-2-propyl [⋅C(CH3)2CH2Cl] and 2-chloro-2-methylpropyl [⋅CH2C(CH3)2Cl] radicals produced in the addition reactions of Cl with isobutene (i-C4H8) in solid para-hydrogen.

    PubMed

    Chou, Ching-Yin; Lee, Yuan-Pern

    2016-10-07

    The addition reactions of chlorine atom with isobutene (i-C 4 H 8 ) in solid para-hydrogen (p-H 2 ) were investigated with infrared (IR) absorption spectra. When a p-H 2 matrix containing Cl 2 and isobutene was irradiated with ultraviolet light at 365 nm, intense lines in a set at 534.5, 1001.0, 1212.9, 1366.0, 2961.6, and 2934.7 cm -1 , and several weaker others due to the 1-chloro-2-methyl-2-propyl radical, ⋅ C(CH 3 ) 2 CH 2 Cl, and those in a second set including intense ones at 642.7, 799.2, 1098.2, 1371.8, and 3027.3 cm -1 due to the 2-chloro-2-methylpropyl radical, ⋅ CH 2 C(CH 3 ) 2 Cl, appeared; the ratio of ⋅ C(CH 3 ) 2 CH 2 Cl to ⋅ CH 2 C(CH 3 ) 2 Cl was approximately (3 ± 1):1. The observed wavenumbers and relative intensities agree with the vibrational wavenumbers and IR intensities predicted with the B3PW91/aug-cc-pVTZ method. That the Cl atom adds to both carbons of the C=C bond of isobutene with the terminal site slightly favored is consistent with the energies of products predicted theoretically, but is in contrast to the reaction of Cl + propene in solid p-H 2 in which the addition of Cl to mainly the central C atom was previously reported. The role of the p-H 2 matrix in affecting the reaction paths is discussed. Absorption lines of the complex i-C 4 H 8 ⋅Cl 2 and the dichloro-product anti-1,2-dichloro-2-methylpropane, a-CH 2 ClCCl(CH 3 ) 2 , are also characterized.

  15. Landscape patterns of CH4 fluxes in an alpine tundra ecosystem

    USGS Publications Warehouse

    West, A.E.; Brooks, P.D.; Fisk, M.C.; Smith, Lesley K.; Holland, E.A.; Jaeger, C. H.; Babcock, S.; Lai, R.S.; Schmidt, S.K.

    1999-01-01

    We measured CH4 fluxes from three major plant communities characteristic of alpine tundra in the Colorado Front Range. Plant communities in this ecosystem are determined by soil moisture regimes induced by winter snowpack distribution. Spatial patterns of CH4 flux during the snow-free season corresponded roughly with these plant communities. In Carex-dominated meadows, which receive the most moisture from snowmelt, net CH4 production occurred. However, CH4 production in one Carex site (seasonal mean = +8.45 mg CH4 m-2 d-1) was significantly larger than in the other Carex sites (seasonal means = -0.06 and +0.05 mg CH4 m-2 d-1). This high CH4 flux may have resulted from shallower snowpack during the winter. In Acomastylis meadows, which have an intermediate moisture regime, CH4 oxidation dominated (seasonal mean = -0.43 mg CH4 m-2 d-1). In the windswept Kobresia meadow plant community, which receive the least amount of moisture from snowmelt, only CH4 oxidation was observed (seasonal mean = -0.77 mg CH4 m-2 d-1). Methane fluxes correlated with a different set of environmental factors within each plant community. In the Carex plant community, CH4 emission was limited by soil temperature. In the Acomastylis meadows, CH4 oxidation rates correlated positively with soil temperature and negatively with soil moisture. In the Kobresia community, CH4 oxidation was stimulated by precipitation. Thus, both snow-free season CH4 fluxes and the controls on those CH4 fluxes were related to the plant communities determined by winter snowpack.

  16. Parallel factor ChIP provides essential internal control for quantitative differential ChIP-seq.

    PubMed

    Guertin, Michael J; Cullen, Amy E; Markowetz, Florian; Holding, Andrew N

    2018-04-17

    A key challenge in quantitative ChIP combined with high-throughput sequencing (ChIP-seq) is the normalization of data in the presence of genome-wide changes in occupancy. Analysis-based normalization methods were developed for transcriptomic data and these are dependent on the underlying assumption that total transcription does not change between conditions. For genome-wide changes in transcription factor (TF) binding, these assumptions do not hold true. The challenges in normalization are confounded by experimental variability during sample preparation, processing and recovery. We present a novel normalization strategy utilizing an internal standard of unchanged peaks for reference. Our method can be readily applied to monitor genome-wide changes by ChIP-seq that are otherwise lost or misrepresented through analytical normalization. We compare our approach to normalization by total read depth and two alternative methods that utilize external experimental controls to study TF binding. We successfully resolve the key challenges in quantitative ChIP-seq analysis and demonstrate its application by monitoring the loss of Estrogen Receptor-alpha (ER) binding upon fulvestrant treatment, ER binding in response to estrodiol, ER mediated change in H4K12 acetylation and profiling ER binding in patient-derived xenographs. This is supported by an adaptable pipeline to normalize and quantify differential TF binding genome-wide and generate metrics for differential binding at individual sites.

  17. ChIPnorm: a statistical method for normalizing and identifying differential regions in histone modification ChIP-seq libraries.

    PubMed

    Nair, Nishanth Ulhas; Sahu, Avinash Das; Bucher, Philipp; Moret, Bernard M E

    2012-01-01

    The advent of high-throughput technologies such as ChIP-seq has made possible the study of histone modifications. A problem of particular interest is the identification of regions of the genome where different cell types from the same organism exhibit different patterns of histone enrichment. This problem turns out to be surprisingly difficult, even in simple pairwise comparisons, because of the significant level of noise in ChIP-seq data. In this paper we propose a two-stage statistical method, called ChIPnorm, to normalize ChIP-seq data, and to find differential regions in the genome, given two libraries of histone modifications of different cell types. We show that the ChIPnorm method removes most of the noise and bias in the data and outperforms other normalization methods. We correlate the histone marks with gene expression data and confirm that histone modifications H3K27me3 and H3K4me3 act as respectively a repressor and an activator of genes. Compared to what was previously reported in the literature, we find that a substantially higher fraction of bivalent marks in ES cells for H3K27me3 and H3K4me3 move into a K27-only state. We find that most of the promoter regions in protein-coding genes have differential histone-modification sites. The software for this work can be downloaded from http://lcbb.epfl.ch/software.html.

  18. Room-temperature enantioselective C-H iodination via kinetic resolution.

    PubMed

    Chu, Ling; Xiao, Kai-Jiong; Yu, Jin-Quan

    2014-10-24

    Asymmetric carbon-hydrogen (C-H) activation reactions often rely on desymmetrization of prochiral C-H bonds on the same achiral molecule, using a chiral catalyst. Here, we report a kinetic resolution via palladium-catalyzed enantioselective C-H iodination in which one of the enantiomers of a racemic benzylic amine substrates undergoes faster aryl C-H insertion with the chiral catalysts than the other. The resulting enantioenriched C-H functionalization products would not be accessible through desymmetrization of prochiral C-H bonds. The exceedingly high relative rate ratio (k(fast)/k(slow) up to 244), coupled with the subsequent iodination of the remaining enantiomerically enriched starting material using a chiral ligand with the opposite configuration, enables conversion of both substrate enantiomers into enantiomerically pure iodinated products. Copyright © 2014, American Association for the Advancement of Science.

  19. Direct dynamics simulation of dioxetane formation and decomposition via the singlet .O-O-CH2-CH2. biradical: Non-RRKM dynamics

    NASA Astrophysics Data System (ADS)

    Sun, Rui; Park, Kyoyeon; de Jong, Wibe A.; Lischka, Hans; Windus, Theresa L.; Hase, William L.

    2012-07-01

    Electronic structure calculations and direct chemical dynamics simulations are used to study the formation and decomposition of dioxetane on its ground state singlet potential energy surface. The stationary points for 1O2 + C2H4, the singlet .O-O-CH2-CH2. biradical, the transition state (TS) connecting this biradical with dioxetane, and the two transition states and gauche .O-CH2-CH2-O. biradical connecting dioxetane with the formaldehyde product molecules are investigated at different levels of electronic structure theory including UB3LYP, UMP2, MRMP2, and CASSCF and a range of basis sets. The UB3LYP/6-31G* method was found to give representative energies for the reactive system and was used as a model for the simulations. UB3LYP/6-31G* direct dynamics trajectories were initiated at the TS connecting the .O-O-CH2-CH2. biradical and dioxetane by sampling the TS's vibrational energy levels, and rotational and reaction coordinate energies, with Boltzmann distributions at 300, 1000, and 1500 K. This corresponds to the transition state theory model for trajectories that pass the TS. The trajectories were directed randomly towards both the biradical and dioxetane. A small fraction of the trajectories directed towards the biradical recrossed the TS and formed dioxetane. The remainder formed 1O2 + C2H4 and of these ˜ 40% went directly from the TS to 1O2 + C2H4 without getting trapped and forming an intermediate in the .O-O-CH2-CH2. biradical potential energy minimum, a non-statistical result. The dioxetane molecules which are formed dissociate to two formaldehyde molecules with a rate constant two orders of magnitude smaller than that predicted by Rice-Ramsperger-Kassel-Marcus theory. The reaction dynamics from dioxetane to the formaldehyde molecules do not follow the intrinsic reaction coordinate or involve trapping in the gauche .O-CH2-CH2-O. biradical potential energy minimum. Important non-statistical dynamics are exhibited for this reactive system.

  20. C-H bond activation of hydrocarbons by an imidozirconocene complex.

    PubMed

    Hoyt, Helen M; Michael, Forrest E; Bergman, Robert G

    2004-02-04

    Monomeric imidozirconocene complexes of the type Cp2(L)Zr=NCMe3 (Cp = cyclopentadienyl, L = Lewis base) have been shown to activate the carbon-hydrogen bonds of benzene, but not the C-H bonds of saturated hydrocarbons. To our knowledge, this singularly important class of C-H activation reactions has heretofore not been observed in imidometallocene systems. The M=NR bond formed on heating the racemic ethylenebis(tetrahydro)indenyl methyl tert-butyl amide complex, however, cleanly and quantitatively activates a wide range of n-alkane, alkene, and arene C-H bonds. Mechanistic experiments support the proposal of intramolecular elimination of methane followed by a concerted addition of the hydrocarbon C-H bond. Products formed by activation of sp2 C-H bonds are generally more thermodynamically stable than those formed by activation of sp3 C-H bonds, and those resulting from reaction at primary C-H bonds are preferred over secondary sp3 C-H activation products. There is also evidence that thermodynamic selectivity among C-H bonds is sterically rather than electronically controlled.

  1. Mapping pan-Arctic CH4 emissions using an adjoint method by integrating process-based wetland and lake biogeochemical models and atmospheric CH4 concentrations

    NASA Astrophysics Data System (ADS)

    Tan, Z.; Zhuang, Q.; Henze, D. K.; Frankenberg, C.; Dlugokencky, E. J.; Sweeney, C.; Turner, A. J.

    2015-12-01

    Understanding CH4 emissions from wetlands and lakes are critical for the estimation of Arctic carbon balance under fast warming climatic conditions. To date, our knowledge about these two CH4 sources is almost solely built on the upscaling of discontinuous measurements in limited areas to the whole region. Many studies indicated that, the controls of CH4 emissions from wetlands and lakes including soil moisture, lake morphology and substrate content and quality are notoriously heterogeneous, thus the accuracy of those simple estimates could be questionable. Here we apply a high spatial resolution atmospheric inverse model (nested-grid GEOS-Chem Adjoint) over the Arctic by integrating SCIAMACHY and NOAA/ESRL CH4 measurements to constrain the CH4 emissions estimated with process-based wetland and lake biogeochemical models. Our modeling experiments using different wetland CH4 emission schemes and satellite and surface measurements show that the total amount of CH4 emitted from the Arctic wetlands is well constrained, but the spatial distribution of CH4 emissions is sensitive to priors. For CH4 emissions from lakes, our high-resolution inversion shows that the models overestimate CH4 emissions in Alaskan costal lowlands and East Siberian lowlands. Our study also indicates that the precision and coverage of measurements need to be improved to achieve more accurate high-resolution estimates.

  2. Thermodynamic and hydrochemical controls on CH4 in a coal seam gas and overlying alluvial aquifer: new insights into CH4 origins

    PubMed Central

    Owen, D. Des. R.; Shouakar-Stash, O.; Morgenstern, U.; Aravena, R.

    2016-01-01

    Using a comprehensive data set (dissolved CH4, δ13C-CH4, δ2H-CH4, δ13C-DIC, δ37Cl, δ2H-H2O, δ18O-H2O, Na, K, Ca, Mg, HCO3, Cl, Br, SO4, NO3 and DO), in combination with a novel application of isometric log ratios, this study describes hydrochemical and thermodynamic controls on dissolved CH4 from a coal seam gas reservoir and an alluvial aquifer in the Condamine catchment, eastern Surat/north-western Clarence-Moreton basins, Australia. δ13C-CH4 data in the gas reservoir (−58‰ to −49‰) and shallow coal measures underlying the alluvium (−80‰ to −65‰) are distinct. CO2 reduction is the dominant methanogenic pathway in all aquifers, and it is controlled by SO4 concentrations and competition for reactants such as H2. At isolated, brackish sites in the shallow coal measures and alluvium, highly depleted δ2H-CH4 (<310‰) indicate acetoclastic methanogenesis where SO4 concentrations inhibit CO2 reduction. Evidence of CH4 migration from the deep gas reservoir (200–500 m) to the shallow coal measures (<200 m) or the alluvium was not observed. The study demonstrates the importance of understanding CH4 at different depth profiles within and between aquifers. Further research, including culturing studies of microbial consortia, will improve our understanding of the occurrence of CH4 within and between aquifers in these basins. PMID:27578542

  3. A vacuum ultraviolet laser pulsed field ionization-photoion study of methane (CH 4): Determination of the appearance energy of methylium from methane with unprecedented precision and the resulting impact on the bond dissociation energies of CH 4 and CH 4 +

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

    Chang, Yih -Chung; Xiong, Bo; Bross, David H.

    Here, we report on the successful implementation of a high-resolution vacuum ultraviolet (VUV) laser pulsed field ionization-photoion (PFI-PI) detection method for the study of unimolecular dissociation of quantum-state- or energy-selected molecular ions. As a test case, we have determined the 0 K appearance energy (AE 0) for the formation of methylium, CH 3 +, from methane, CH 4, as AE 0 (CH 3 +/CH 4) = 14.32271 ± 0.00013 eV. This value has a significantly smaller error limit, but is otherwise consistent with previous laboratory and/or synchrotron-based studies of this dissociative photoionization onset. Furthermore, the sum of the VUV lasermore » PFI-PI spectra obtained for the parent CH 4 + ion and the fragment CH 3 + ions of methane is found to agree with the earlier VUV pulsed field ionization-photoelectron (VUV-PFI-PE) spectrum of methane, providing unambiguous validation of the previous interpretation that the sharp VUV-PFI-PE step observed at the AE 0 (CH 3 +/CH 4) threshold ensues because of higher PFI detection efficiency for fragment CH 3 + than for parent CH 4 +. This, in turn, is a consequence of the underlying high- n Rydberg dissociation mechanism for the dissociative photoionization of CH 4, which was proposed in previous synchrotron-based VUV-PFI-PE and VUV-PFI-PEPICO studies of CH 4. The present highly accurate 0 K dissociative ionization threshold for CH 4 can be utilized to derive accurate values for the bond dissociation energies of methane and methane cation. For methane, the straightforward application of sequential thermochemistry via the positive ion cycle leads to some ambiguity because of two competing VUV-PFI-PE literature values for the ionization energy of methyl radical. The ambiguity is successfully resolved by applying the Active Thermochemical Tables (ATcT) approach, resulting in D 0 (H-CH 3) = 432.463 ± 0.027 kJ/mol and D 0(H-CH 3 +) = 164.701 ± 0.038 kJ/mol.« less

  4. A vacuum ultraviolet laser pulsed field ionization-photoion study of methane (CH 4): Determination of the appearance energy of methylium from methane with unprecedented precision and the resulting impact on the bond dissociation energies of CH 4 and CH 4 +

    DOE PAGES

    Chang, Yih -Chung; Xiong, Bo; Bross, David H.; ...

    2017-03-27

    Here, we report on the successful implementation of a high-resolution vacuum ultraviolet (VUV) laser pulsed field ionization-photoion (PFI-PI) detection method for the study of unimolecular dissociation of quantum-state- or energy-selected molecular ions. As a test case, we have determined the 0 K appearance energy (AE 0) for the formation of methylium, CH 3 +, from methane, CH 4, as AE 0 (CH 3 +/CH 4) = 14.32271 ± 0.00013 eV. This value has a significantly smaller error limit, but is otherwise consistent with previous laboratory and/or synchrotron-based studies of this dissociative photoionization onset. Furthermore, the sum of the VUV lasermore » PFI-PI spectra obtained for the parent CH 4 + ion and the fragment CH 3 + ions of methane is found to agree with the earlier VUV pulsed field ionization-photoelectron (VUV-PFI-PE) spectrum of methane, providing unambiguous validation of the previous interpretation that the sharp VUV-PFI-PE step observed at the AE 0 (CH 3 +/CH 4) threshold ensues because of higher PFI detection efficiency for fragment CH 3 + than for parent CH 4 +. This, in turn, is a consequence of the underlying high- n Rydberg dissociation mechanism for the dissociative photoionization of CH 4, which was proposed in previous synchrotron-based VUV-PFI-PE and VUV-PFI-PEPICO studies of CH 4. The present highly accurate 0 K dissociative ionization threshold for CH 4 can be utilized to derive accurate values for the bond dissociation energies of methane and methane cation. For methane, the straightforward application of sequential thermochemistry via the positive ion cycle leads to some ambiguity because of two competing VUV-PFI-PE literature values for the ionization energy of methyl radical. The ambiguity is successfully resolved by applying the Active Thermochemical Tables (ATcT) approach, resulting in D 0 (H-CH 3) = 432.463 ± 0.027 kJ/mol and D 0(H-CH 3 +) = 164.701 ± 0.038 kJ/mol.« less

  5. Supervisors and accomplices: extra-marital sex among migrant construction workers in Ha Noi, Viet Nam.

    PubMed

    Thuy, Bui Thi Thanh; Kretchmar, Joshua

    2008-06-01

    This study examines the influence of social networks on the sexual relations of migrant construction workers in Ha Noi, Viet Nam. Research included observation and interviews with members of two different groups of workers. The first group, together with their employer (cai), came from the same village; the second group came from different villages. Of interest in the present study was how social relationships among workers and their employers influence extra-marital sexual activity. In the group where workers and their cai came from the same village of origin, fear of acquiring a bad reputation made these workers reluctant to seek sex services, since accounts of their behaviour were transmitted quickly home. In contrast, workers from the group who came from different villages often went out together to purchase sex. The absence of direct links to their villages of origin made it easier for these latter workers to conceal their activity. The implication of these findings for sexual safety and risk are discussed.

  6. FunChIP: an R/Bioconductor package for functional classification of ChIP-seq shapes.

    PubMed

    Parodi, Alice C L; Sangalli, Laura M; Vantini, Simone; Amati, Bruno; Secchi, Piercesare; Morelli, Marco J

    2017-08-15

    Chromatin Immunoprecipitation followed by sequencing (ChIP-seq) generates local accumulations of sequencing reads on the genome ("peaks"), which correspond to specific protein-DNA interactions or chromatin modifications. Peaks are detected by considering their total area above a background signal, usually neglecting their shapes, which instead may convey additional biological information. We present FunChIP, an R/Bioconductor package for clustering peaks according to a functional representation of their shapes: after approximating their profiles with cubic B-splines, FunChIP minimizes their functional distance and classifies the peaks applying a k-mean alignment and clustering algorithm. The whole pipeline is user-friendly and provides visualization functions for a quick inspection of the results. An application to the transcription factor Myc in 3T9 murine fibroblasts shows that clusters of peaks with different shapes are associated with different genomic locations and different transcriptional regulatory activity. The package is implemented in R and is available under Artistic Licence 2.0 from the Bioconductor website (http://bioconductor.org/packages/FunChIP). marco.morelli@iit.it. Supplementary data are available at Bioinformatics online. © The Author (2017). Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com

  7. A laser flash photolysis-resonance fluorescence kinetics study of the reaction Cl/2P/ + CH4 yields CH3 + HCl

    NASA Technical Reports Server (NTRS)

    Ravishankara, A. R.; Wine, P. H.

    1980-01-01

    The technique of laser flash photolysis-resonance fluorescence is employed to study the kinetics of the reaction Cl(2P) + CH4 yields CH3 + HCl over the temperature range 221-375 K. At temperatures less than or equal to 241 K the apparent bimolecular rate constant is found to be dependent upon the identity of the chemically inert gases in the reaction mixture. For Cl2/CH4/He reaction mixtures (total pressure = 50 torr) different bimolecular rate constants are measured at low and high methane concentrations. For Cl2/CH4/CCl/He and Cl2/CH4/Ar reaction mixtures, the bimolecular rate constant is independent of methane concentration, being approximately equal to the rate constant measured at low methane concentrations for Cl2/CH4/He mixtures. These rate constants are in good agreement with previous results obtained using the discharge flow-resonance fluorescence and competitive chlorination techniques. At 298 K the measured bimolecular rate constant is independent of the identity of the chemically inert gases in the reaction mixture and in good agreement with all previous investigations. The low-temperature results obtained in this investigation and all previous investigations can be rationalized in terms of a model which assumes that the Cl(2P 1/2) state reacts with CH4 much faster than the Cl(2P 3/2) state. Extrapolation of this model to higher temperatures, however, is not straightforward.

  8. The ChArMEx database

    NASA Astrophysics Data System (ADS)

    Ferré, Hélène; Descloitres, Jacques; Fleury, Laurence; Boichard, Jean-Luc; Brissebrat, Guillaume; Focsa, Loredana; Henriot, Nicolas; Mastrorillo, Laurence; Mière, Arnaud; Vermeulen, Anne

    2013-04-01

    The Chemistry-Aerosol Mediterranean Experiment (ChArMEx, http://charmex.lsce.ipsl.fr/) aims at a scientific assessment of the present and future state of the atmospheric environment in the Mediterranean Basin, and of its impacts on the regional climate, air quality, and marine biogeochemistry. The project includes long term monitoring of environmental parameters, intensive field campaigns, use of satellite data and modelling studies. Therefore ChARMEx scientists produce and need to access a wide diversity of data. In this context, the objective of the database task is to organize data management, distribution system and services such as facilitating the exchange of information and stimulating the collaboration between researchers within the ChArMEx community, and beyond. The database relies on a strong collaboration between OMP and ICARE data centres and falls within the scope of the Mediterranean Integrated Studies at Regional And Locals Scales (MISTRALS) program data portal. All the data produced by or of interest for the ChArMEx community will be documented in the data catalogue and accessible through the database website: http://mistrals.sedoo.fr/ChArMEx. The database website offers different tools: - A registration procedure which enables any scientist to accept the data policy and apply for a user database account. - Forms to document observations or products that will be provided to the database in compliance with metadata international standards (ISO 19115-19139; INSPIRE; Global Change Master Directory Thesaurus). - A search tool to browse the catalogue using thematic, geographic and/or temporal criteria. - Sorted lists of the datasets by thematic keywords, by measured parameters, by instruments or by platform type. - A shopping-cart web interface to order in situ data files. At present datasets from the background monitoring station of Ersa, Cape Corsica and from the 2012 ChArMEx pre-campaign are available. - A user-friendly access to satellite products

  9. Neurobehavioral and quality of life changes associated with growth hormone insufficiency after complicated mild, moderate, or severe traumatic brain injury.

    PubMed

    Kelly, Daniel F; McArthur, David L; Levin, Harvey; Swimmer, Shana; Dusick, Joshua R; Cohan, Pejman; Wang, Christina; Swerdloff, Ronald

    2006-06-01

    Adult-onset growth hormone deficiency (GHD) has been associated with reduced quality of life (QOL) and neurobehavioral (NB) deficits. This prospective study tested the hypothesis that traumatic brain injury (TBI) patients with GHD or GH insufficiency (GHI) would exhibit greater NB/QOL impairment than patients without GHD/GHI. Complicated mild, moderate, and severe adult TBI patients (GCS score 3-14) had pituitary function and NB/QOL testing performed 6-9 months postinjury. GH-secretory capacity was assessed with a GHRH-arginine stimulation test and GHD and GHI were defined as peak GH<6 or GHI, and 36 (82%) were GH-sufficient at 6-9 months post-injury. Mean peak GH was 8.2+/-2.1 ng/mL in the GHD/GHI group versus 45.7+/-29 ng/mL in the GHsufficient group. The two groups were well-matched in injury characteristics, except that one patient with GHD had central hypogonadism treated with testosterone prior to NB/QOL testing. At 6-9 months postinjury, patients with GHD/GHI had higher rates of at least one marker of depression (p<0.01), and reduced QOL (by SF-36 Health Survey) in the domains of limitations due to physical health (p=0.02), energy and fatigue (p=0.05), emotional well-being (p=0.02), pain (p=0.01), and general health (p=0.05). Chronic GHI develops in approximately 18% of patients with complicated mild, moderate, or severe TBI, and is associated with depression and diminished QOL. The impact of GH replacement therapy on NB function and QOL in these TBI patients is being tested in a randomized placebo-controlled trial.

  10. Photolysis of CH{sub 3}CHO at 248 nm: Evidence of triple fragmentation from primary quantum yield of CH{sub 3} and HCO radicals and H atoms

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

    Morajkar, Pranay; Schoemaecker, Coralie; Fittschen, Christa, E-mail: christa.fittschen@univ-lille1.fr

    2014-06-07

    Radical quantum yields have been measured following the 248 nm photolysis of acetaldehyde, CH{sub 3}CHO. HCO radical and H atom yields have been quantified by time resolved continuous wave Cavity Ring Down Spectroscopy in the near infrared following their conversion to HO{sub 2} radicals by reaction with O{sub 2}. The CH{sub 3} radical yield has been determined using the same technique following their conversion into CH{sub 3}O{sub 2}. Absolute yields have been deduced for HCO radicals and H atoms through fitting of time resolved HO{sub 2} profiles, obtained under various O{sub 2} concentrations, to a complex model, while the CH{submore » 3} yield has been determined relative to the CH{sub 3} yield from 248 nm photolysis of CH{sub 3}I. Time resolved HO{sub 2} profiles under very low O{sub 2} concentrations suggest that another unknown HO{sub 2} forming reaction path exists in this reaction system besides the conversion of HCO radicals and H atoms by reaction with O{sub 2}. HO{sub 2} profiles can be well reproduced under a large range of experimental conditions with the following quantum yields: CH{sub 3}CHO + hν{sub 248nm} → CH{sub 3}CHO{sup *}, CH{sub 3}CHO{sup *} → CH{sub 3} + HCO ϕ{sub 1a} = 0.125 ± 0.03, CH{sub 3}CHO{sup *} → CH{sub 3} + H + CO ϕ{sub 1e} = 0.205 ± 0.04, CH{sub 3}CHO{sup *}→{sup o{sub 2}}CH{sub 3}CO + HO{sub 2} ϕ{sub 1f} = 0.07 ± 0.01. The CH{sub 3}O{sub 2} quantum yield has been determined in separate experiments as ϕ{sub CH{sub 3}} = 0.33 ± 0.03 and is in excellent agreement with the CH{sub 3} yields derived from the HO{sub 2} measurements considering that the triple fragmentation (R1e) is an important reaction path in the 248 nm photolysis of CH{sub 3}CHO. From arithmetic considerations taking into account the HO{sub 2} and CH{sub 3} measurements we deduce a remaining quantum yield for the molecular pathway: CH{sub 3}CHO{sup *} → CH{sub 4} + CO ϕ{sub 1b} = 0.6. All experiments

  11. Atmospheric lifetimes and ozone depletion potentials of methyl bromide (CH3Br) and dibromomethane (CH2Br2)

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

    Mellouki, A.; Talukdar, R.K.; Schmoltner, A.

    The rate coefficients for the reactions of OH radical with CH3Br and CH2Br2 were measured as functions of temperature using the laser photolysis - laser induced fluorescence method. This data was incorporated into a semiempirical model (Solomon et al., 1992) and a 2D model to calculate the steady-state ozone depletion potentials (ODP) and atmospheri lifetimes, tau, with greatly improved accuracy as compared to earlier studies. The calculated ODPs and tau are 0.65 and 1.7 years and 0.17 and 0.41 years for CH3Br and CH2Br2, respectively, using the semiempirical model. These lifetimes agree well with those calculated using a 2D model.more » This study better quantifies the ODPs and tau of these species which are needed inputs for discussion of possible regulation of human emissions currently under international considerations. 29 refs.« less

  12. Methanesulfonates of high-valent metals: syntheses and structural features of MoO2(CH3SO3)2, UO2(CH3SO3)2, ReO3(CH3SO3), VO(CH3SO3)2, and V2O3(CH3SO3)4 and their thermal decomposition under N2 and O2 atmosphere.

    PubMed

    Betke, Ulf; Neuschulz, Kai; Wickleder, Mathias S

    2011-11-04

    Oxide methanesulfonates of Mo, U, Re, and V have been prepared by reaction of MoO(3), UO(2)(CH(3)COO)(2)·2H(2)O, Re(2)O(7)(H(2)O)(2), and V(2)O(5) with CH(3)SO(3)H or mixtures thereof with its anhydride. These compounds are the first examples of solvent-free oxide methanesulfonates of these elements. MoO(2)(CH(3)SO(3))(2) (Pbca, a=1487.05(4), b=752.55(2), c=1549.61(5) pm, V=1.73414(9) nm(3), Z=8) contains [MoO(2)] moieties connected by [CH(3)SO(3)] ions to form layers parallel to (100). UO(2)(CH(3)SO(3))(2) (P2(1)/c, a=1320.4(1), b=1014.41(6), c=1533.7(1) pm, β=112.80(1)°, V=1.8937(3) nm(3), Z=8) consists of linear UO(2)(2+) ions coordinated by five [CH(3)SO(3)] ions, forming a layer structure. VO(CH(3)SO(3))(2) (P2(1)/c, a=1136.5(1), b=869.87(7), c=915.5(1) pm, β=113.66(1)°, V=0.8290(2) nm(3), Z=4) contains [VO] units connected by methanesulfonate anions to form corrugated layers parallel to (100). In ReO(3)(CH(3)SO(3)) (P1, a=574.0(1), b=1279.6(3), c=1641.9(3) pm, α=102.08(2), β=96.11(2), γ=99.04(2)°, V=1.1523(4) nm(3), Z=8) a chain structure exhibiting infinite O-[ReO(2)]-O-[ReO(2)]-O chains is formed. Each [ReO(2)]-O-[ReO(2)] unit is coordinated by two bidentate [CH(3)SO(3)] ions. V(2)O(3)(CH(3)SO(3))(4) (I2/a, a=1645.2(3), b=583.1(1), c=1670.2(3) pm, β=102.58(3), V=1.5637(5) pm(3), Z=4) adopts a chain structure, too, but contains discrete [VO]-O-[VO] moieties, each coordinated by two bidentate [CH(3)SO(3)] ligands. Additional methanesulfonate ions connect the [V(2)O(3)] groups along [001]. Thermal decomposition of the compounds was monitored under N(2) and O(2) atmosphere by thermogravimetric/differential thermal analysis and XRD measurements. Under N(2) the decomposition proceeds with reduction of the metal leading to the oxides MoO(2), U(3)O(7), V(4)O(7), and VO(2); for MoO(2)(CH(3)SO(3))(2), a small amount of MoS(2) is formed. If the thermal decomposition is carried out in a atmosphere of O(2) the oxides MoO(3) and V(2)O(5) are formed. Copyright

  13. Analysis of the heat capacity for pure CH4 and CH4/CCl4 on graphite near the melting point and calculation of the T-X phase diagram for (CH3)CCl3 + CCl4

    NASA Astrophysics Data System (ADS)

    Yurtseven, Hamit; Yılmaz, Aygül

    2016-06-01

    We study the temperature dependence of the heat capacity Cp for the pure CH4 and the coadsorbed CH4/CCl4 on graphite near the melting point. The heat capacity peaks are analyzed using the experimental data from the literature by means of the power-law formula. The critical exponents for the heat capacity are deduced below and above the melting point for CH4 (Tm = 104.8 K) and CH4/CCl4 (Tm = 99.2 K). Our exponent values are larger as compared with the predicted values of some theoretical models exhibiting second order transition. Our analyses indicate that the pure methane shows a nearly second order (weak discontinuity in the heat capacity peak), whereas the transition in coadsorbed CH4/CCl4 is of first order (apparent discontinuity in Cp). We also study the T - X phase diagram of a two-component system of CH3CCl3+CCl4 using the Landau phenomenological model. Phase lines of the R+L (rhombohedral+liquid) and FCC+L (face-centred cubic + liquid) are calculated using the observed T - X phase diagram of this binary mixture. Our results show that the Landau mean field theory describes the observed behavior of CH3CCl3+CCl4 adequately. From the calculated T - X phase diagram, critical behavior of some thermodynamic quantities can be predicted at various temperatures and concentrations (CCl4) for a binary mixture of CH3CCl3+CCl4.

  14. Southeast Asia Report.

    DTIC Science & Technology

    1984-03-21

    Political, Economic Development, Hospital (Dao Don Khong; PASASON, 18 Jan 84) . 30 Planned Nam Ngum Hydropower Production, Expansion (Ch...Participation in Economic Construction (Editorial; QUAN DOI NHAN DAN, 11 Jan 84) 99 Thanh Tri District Military Commander Interviewed (Vuong Si Dinh...specifically you young people who must go on fighting. I am 75 already—what more do you want," he asked firmly. His life history, as written in the

  15. Computational Studies Of Chemical Reactions: The Hnc-Hcn And Ch[subscript3]Nc-Ch[subscript3]Cn Isomerizations

    ERIC Educational Resources Information Center

    Halpern, Arthur M.

    2006-01-01

    The application of computational methods to the isomerization of hydrogen isocyanide to hydrogen cyanide, HNC-HCN is described. The logical extension to the exercise is presented to the isomerization of the methyl-substituted compounds, methylisocyanide and methylcyanide, Ch[subscript 3]NC-CH[subscript3]CN.

  16. Synthesis, characterization, structural and biological aspects of copper(II) dithiocarbamate complexes - Part II, [Cu{S2CN(Me)(R1)}2], [Cu{S2CN(Me)(R2)}2] and [Cu{S2CN(R3)(R4)}2] {R1 = CH2CH(OMe)2, R2 = 2-methyl-1,3-dioxolane, R3 = CH2(CH2)2NCHPhOCH2Ph and R4 = CH2CH2OH}

    NASA Astrophysics Data System (ADS)

    Ferreira, Isabella P.; de Lima, Geraldo M.; Paniago, Eucler B.; Takahashi, Jacqueline A.; Krambrock, Klaus; Pinheiro, Carlos B.; Wardell, James L.; Visentin, Lorenzo C.

    2013-09-01

    Three new copper(II) dithiocarbamates (DTC), [Cu{S2CN(Me)(R1)}2] (1), [Cu{S2CN(Me)(R2)}2] (2) and [Cu{S2CN(R3)(R4)}2] (3) with R1 = CH2CH(OMe)2, R2 = 2-methyl-1,3-dioxolane, R3 = CH2(CH2)2NCHPhOCH2Ph and R4 = CH2CH2OH, have been synthesized and characterized by different spectroscopic techniques. Complexes (1) and (2) display typical EPR spectra for separated Cu(II) centers, and the spectrum of (3) is characteristic of two magnetically coupled Cu(II) ions with S = 1. The X-ray crystallographic determination has shown that complexes (1) and (2) crystallise in the triclinic and monoclinic systems. In addition both complexes are monomers in which the geometry at each Cu(II) is square planar. The in vitro antimicrobial activity of the sodium salts of ligands, and of the Cu(II)-DTC complexes have been screened against Aspergillus flavus, Aspergillus niger, Aspergillus parasiticus, Penicillium citrinum and Curvularia senegalensis, as well as Gram positive and Gram negative bacteria. Finally, the toxic effects of complexes (1)-(3) were performed using Chlorella vulgaris.

  17. The Relative Abundances of Resolved 12CH2D2 and 13CH3D and Mechanisms Controlling Isotopic Bond Ordering in Abiotic and Biotic Methane Gases

    NASA Astrophysics Data System (ADS)

    Young, E. D.; Kohl, I. E.; Sherwood Lollar, B.; Etiope, G.; Rumble, D.; Li, S.; Haghnegahdar, M. A.; Schauble, E. A.; McCain, K.; Foustoukos, D.; Sutcliffe, C. N.; Warr, O.; Ballentine, C. J.; Onstott, T. C.; Hosgormez, H.; Neubeck, A.; Marques, J. M.; Perez-Rodriguez, I. M.; Rowe, A. R.; LaRowe, D.; Magnabosco, C.; Bryndzia, T.

    2016-12-01

    We report measurements of resolved 12CH2D2 and 13CH3D at natural abundances in a variety of methane gases produced naturally and in the laboratory. The ability to resolve 12CH2D2 from 13CH3D provides unprecedented insights into the origin and evolution of CH4. The results identify conditions under which either isotopic bond order disequilibrium or equilibrium are expected. Where equilibrium obtains, concordant Δ12CH2D2 and Δ13CH3D temperatures can be used reliably for thermometry. We find that concordant temperatures do not always match previous hypotheses based on indirect estimates of temperature of formation nor temperatures derived from CH4/H2 D/H exchange, underscoring the importance of reliable thermometry based on the CH4 molecules themselves. Where Δ12CH2D2 and Δ13CH3D values are inconsistent with thermodynamic equilibrium, temperatures of formation derived from these species are spurious. In such situations, while formation temperatures are unavailable, disequilibrium isotopologue ratios nonetheless provide important information about the formation mechanism of the gas and the presence or absence of multiple sources or sinks. In particular, disequilibrium isotopologue ratios may provide the means for differentiating between methane produced by abiotic synthesis versus biological processes. Deficits in 12CH2D2 compared with equilibrium values in CH4 gas made by surface-catalyzed abiotic reactions are so large as to point towards a quantum tunneling origin. Tunneling also accounts for the more moderate depletions in 13CH3D that accompany the low 12CH2D2 abundances produced by abiotic reactions. The tunneling signature of abiotic CH4 formation may prove to be an important tracer of abiotic methane formation, especially where it is preserved by dissolution of gas in cool hydrothermal systems (e.g., Mars). Isotopologue signatures of abiotic methane production can be erased by infiltration of microbial communities, and Δ12CH2D2 values are a key tracer of

  18. iTAR: a web server for identifying target genes of transcription factors using ChIP-seq or ChIP-chip data.

    PubMed

    Yang, Chia-Chun; Andrews, Erik H; Chen, Min-Hsuan; Wang, Wan-Yu; Chen, Jeremy J W; Gerstein, Mark; Liu, Chun-Chi; Cheng, Chao

    2016-08-12

    Chromatin immunoprecipitation followed by massively parallel DNA sequencing (ChIP-seq) or microarray hybridization (ChIP-chip) has been widely used to determine the genomic occupation of transcription factors (TFs). We have previously developed a probabilistic method, called TIP (Target Identification from Profiles), to identify TF target genes using ChIP-seq/ChIP-chip data. To achieve high specificity, TIP applies a conservative method to estimate significance of target genes, with the trade-off being a relatively low sensitivity of target gene identification compared to other methods. Additionally, TIP's output does not render binding-peak locations or intensity, information highly useful for visualization and general experimental biological use, while the variability of ChIP-seq/ChIP-chip file formats has made input into TIP more difficult than desired. To improve upon these facets, here we present are fined TIP with key extensions. First, it implements a Gaussian mixture model for p-value estimation, increasing target gene identification sensitivity and more accurately capturing the shape of TF binding profile distributions. Second, it enables the incorporation of TF binding-peak data by identifying their locations in significant target gene promoter regions and quantifies their strengths. Finally, for full ease of implementation we have incorporated it into a web server ( http://syslab3.nchu.edu.tw/iTAR/ ) that enables flexibility of input file format, can be used across multiple species and genome assembly versions, and is freely available for public use. The web server additionally performs GO enrichment analysis for the identified target genes to reveal the potential function of the corresponding TF. The iTAR web server provides a user-friendly interface and supports target gene identification in seven species, ranging from yeast to human. To facilitate investigating the quality of ChIP-seq/ChIP-chip data, the web server generates the chart of the

  19. a Theoretical Characterization of Electronic States of CH2IOO and CH2OO Radicals Relevant to the Near IR Region

    NASA Astrophysics Data System (ADS)

    Dawes, Richard; Lolur, Phalgun; Huang, Meng; Kline, Neal; Miller, Terry A.

    2015-06-01

    Criegee intermediates (R1R2COO or CIs) arise from ozonolysis of biogenic and anthropogenic alkenes, which is an important process in the atmosphere. Recent breakthroughs in producing them in the gas phase have resulted in a flurry of experimental and theoretical studies. Producing the simplest CI (CH2OO) in the lab via photolysis of CH2I2 in the presence of O2 yields both CH2OO and CH2IOO with pressure dependent branching. As discussed in the preceding talk, both species might be expected to have electronic transitions in the near IR (NIR). Here we discuss electronic structure calculations used to characterize the electronic states of both systems in the relevant energy range. Using explicitly-correlated multireference configuration interaction (MRCI-F12) and coupled-cluster (UCCSD(T)-F12b) calculations we were first able to exclude CH2OO as the carrier of the observed NIR spectrum. Next, by computing frequencies and relaxed full torsional scans for the ~A and ~X states, we were able to aid in analysis and assignment of the NIR spectrum attributed to CH2IOO.

  20. Theoretical study on the reaction mechanism of CH 4 with CaO

    NASA Astrophysics Data System (ADS)

    Yang, Hua-Qing; Hu, Chang-Wei; Qin, Song

    2006-11-01

    The reaction pathways and energetics for the reaction of methane with CaO are discussed on the singlet spin state potential energy surface at the B3LYP/6-311+G(2df,2p) and QCISD/6-311++G(3df,3pd)//B3LYP/6-311+G(2df,2p) levels of theory. The reaction of methane with CaO is proposed to proceed in the following reaction pathways: CaO + CH 4 → CaOCH 4 → [TS] → CaOH + CH 3, CaO + CH 4 → OCaCH 4 → [TS] → HOCaCH 3 → CaOH + CH 3 or [TS] → CaCH 3OH → Ca + CH 3OH, and OCaCH 4 → [TS] → HCaOCH 3 → CaOCH 3 + H or [TS] → CaCH 3OH → Ca + CH 3OH. The gas-phase methane-methanol conversion by CaO is suggested to proceed via two kinds of important reaction intermediates, HOCaCH 3 and HCaOCH 3, and the reaction pathway via the hydroxy intermediate (HOCaCH 3) is energetically more favorable than the other one via the methoxy intermediate (HCaOCH 3). The hydroxy intermediate HOCaCH 3 is predicted to be the energetically most preferred configuration in the reaction of CaO + CH 4. Meanwhile, these three product channels (CaOH + CH 3, CaOCH 3 + H and Ca + CH 3OH) are expected to compete with each other, and the formation of methyl radical is the most preferable pathway energetically. On the other hand, the intermediates HCaOCH 3 and HOCaCH 3 are predicted to be the energetically preferred configuration in the reaction of Ca + CH 3OH, which is precisely the reverse reaction of methane hydroxylation.

  1. Tree CH4 fluxes in forestry drained peatland in southern Finland

    NASA Astrophysics Data System (ADS)

    Haikarainen, Iikka; Putkinen, Anuliina; Pyykkö, Petteri; Halmeenmäki, Elisa; Pihlatie, Mari

    2017-04-01

    Methane (CH4) is among the most important greenhouse gases and its atmospheric concentration is increasing. Boreal forests are commonly considered a net sink of atmospheric CH4 due to CH4 consuming bacteria in aerated soil layers. Recent studies have, however, demonstrated that trees are capable of emitting CH4 from their stems and shoots by transporting anaerobically produced CH4 from deeper soil layers to the atmosphere. Furthermore, trees may act as independent sources of CH4. We have measured tree stem CH4 exchange of boreal tree species at Lettosuo, a nutrient rich peatland forest in Tammela, southern Finland (60˚ 38' N, 23˚ 57' E), using the static chamber technique. Three species, downy birch (Betula pubescens), Norway spruce (Picea abies) and Scots pine (Pinus sylvestris), were selected under investigation as they represent common boreal tree species. Fluxes of CH4 were measured during 7.6.2016 - 17.10.2016 from in total 25 sample trees growing on two different plots: a treatment plot where all the pines were removed to raise the water table level (WTL) and a control plot. Three birches from the treatment plot were selected to measure CH4 flux variation within vertical profile of the trees. Characterization of microbial communities, quantification of methanogenic and methanotrophic functional genes, and measurements of potential CH4 production and consumption from peat profile and forest floor moss samples were also carried out to obtain insight to the CH4 flux dynamics at the studied sites. The pine removal treatment did not markedly change the average WTL, but it made the WTL more variable with frequently 10-15 cm closer to soil surface compared to the WTL on the control plot. We found small and variable CH4 emissions from the stems of trees on both of the plots, while occasional consumption of CH4 was also present. Generally the CH4 emissions were higher and more dominant at the treatment plot compared to the control plot, and the fluxes were

  2. Cigarette Smoking among Adolescents aged 13-15 in Viet Nam and Correlates of Current Cigarette Smoking: Results from GYTS 2014 Data.

    PubMed

    Huong, Le Thi; Vu, Nga Thi Thu; Dung, Nguyen Ngoc; Xuan, Le Thi Thanh; Giang, Kim Bao; Hai, Phan Thi; Huyen, Doan Thu; Khue, Luong Ngoc; Lam, Nguyen Tuan; Minh, Hoang Van; Nga, Pham Thi Quynh

    2016-01-01

    The aim of this paper is to report the rate of current and ever cigarette smoking and explore correlates of current cigarette smoking among adolescents aged 13-15 in Viet Nam. This analysis was derived from GYTS survey, which comprised of 3,430 adolescents aged 13-15, conducted in 2014 in 13 cities and provinces of Viet Nam. We calculated the weighted rates of current and ever cigarette smoking and reported patterns of smoking behavior. We also performed logistic regression to explore correlates of current cigarette smoking behavior. The weighted rate of ever cigarette smoking was 9.5% (95% confidence interval (CI): 8.5 %-10.5%), in which the weighted rate among males (15.4%; 95% CI: 13.6%-17.0%) was higher than that among females (4.2%; 95% CI: 3.3%-5.1%). The weighted rate of current cigarette smoking was relatively low at 2.5% (95%CI: 2.0%- 3.0%) with higher weighted rate among males (4.9%; 95% CI: 3.8%-5.9%) compared to the corresponding figure among females (0.2%; 95% CI: 0.0 %-0.5%). Current cigarette smoking was significantly higher among males than females, in students aged 15 versus 13 years old, and in students who had several or all close friends smoking and students with daily observation of smoking at school. For greater smoking reduction outcomes, we recommend that tobacco interventions for adolescents should consider targeting more male students at older ages, establish stricter adherence to school-based banning of cigarette smoking, engage both smoking and nonsmoking adolescents and empower adolescents to resist peer smoking influence as well as changing their norms or beliefs towards smoking benefits.

  3. Raman spectroscopy measurement of CH4 gas and CH4 dissolved in water for laser remote sensing in water

    NASA Astrophysics Data System (ADS)

    Somekawa, Toshihiro; Fujita, Masayuki

    2018-04-01

    We examined the applicability of Raman spectroscopy as a laser remote sensing tool for monitoring CH4 in water. The Raman technique has already been used successfully for measurements of CO2 gas in water. In this paper, considering the spectral transmittance of water, third harmonics of Q-switched Nd:YAG laser at 355 nm (UV region) was used for detection of CH4 Raman signals. The Raman signal at 2892 cm-1 from CH4 dissolved in water was detected at a tail of water Raman signal.

  4. Changing concentrations of CO, CH(4), C(5)H(8), CH(3)Br, CH(3)I, and dimethyl sulfide during the Southern Ocean Iron Enrichment Experiments.

    PubMed

    Wingenter, Oliver W; Haase, Karl B; Strutton, Peter; Friederich, Gernot; Meinardi, Simone; Blake, Donald R; Rowland, F Sherwood

    2004-06-08

    Oceanic iron (Fe) fertilization experiments have advanced the understanding of how Fe regulates biological productivity and air-sea carbon dioxide (CO(2)) exchange. However, little is known about the production and consumption of halocarbons and other gases as a result of Fe addition. Besides metabolizing inorganic carbon, marine microorganisms produce and consume many other trace gases. Several of these gases, which individually impact global climate, stratospheric ozone concentration, or local photochemistry, have not been previously quantified during an Fe-enrichment experiment. We describe results for selected dissolved trace gases including methane (CH(4)), isoprene (C(5)H(8)), methyl bromide (CH(3)Br), dimethyl sulfide, and oxygen (O(2)), which increased subsequent to Fe fertilization, and the associated decreases in concentrations of carbon monoxide (CO), methyl iodide (CH(3)I), and CO(2) observed during the Southern Ocean Iron Enrichment Experiments.

  5. The Drivers of the CH4 Seasonal Cycle in the Arctic and What Long-Term Observations of CH4 Imply About Trends in Arctic CH4 Fluxes

    NASA Astrophysics Data System (ADS)

    Sweeney, C.; Karion, A.; Bruhwiler, L.; Miller, J. B.; Wofsy, S. C.; Miller, C. E.; Chang, R. Y.; Dlugokencky, E. J.; Daube, B.; Pittman, J. V.; Dinardo, S. J.

    2012-12-01

    The large seasonal change in the atmospheric column for CH4 in the Arctic is driven by two dominant processes: transport of CH4 from low latitudes and surface emissions throughout the Arctic region. The NOAA ESRL Carbon Cycle Group Aircraft Program along with the NASA funded Carbon in Arctic Reservoirs Vulnerability Experiment (CARVE) have initiated an effort to better understand the factors controlling the seasonal changes in the mole fraction of CH4 in the Arctic with a multi-scale aircraft observing network in Alaska. The backbone of this network is multi-species flask sampling from 500 to 8000 masl that has been conducted every two weeks for the last 10 years over Poker Flat, AK. In addition regular profiles at the interior Alaska site at Poker Flat, NOAA has teamed up with the United States Coast Guard to make profiling flights with continuous observations of CO2, CO, CH4 and Ozone between Kodiak and Barrow every 2 weeks. More recently, CARVE has significantly added to this observational network with targeted flights focused on exploring the variability of CO2, CH4 and CO in the boundary layer both in the interior and the North Slope regions of Alaska. Taken together with the profiling of HIAPER Pole-to-Pole Observations (HIPPO), ground sites at Barrow and a new CARVE interior Alaska surface site just north of Fairbanks, AK, we now have the ability to investigate the full evolution of the seasonal cycle in the Arctic using both the multi-scale sampling offered by the different aircraft platforms as well as the multi-species sampling offered by in-situ and flask sampling. The flasks also provide a valuable tie-point between different platforms so that spatial and temporal gradients can be properly interpreted. In the context of the seasonal cycle observed by the aircraft platforms we will look at long term ground observations over the last 20 years to assess changes in Arctic CH4 emissions which have occurred as a result of 0.6C/decade changes in mean surface

  6. How to Combine ChIP with qPCR.

    PubMed

    Asp, Patrik

    2018-01-01

    Chromatin immunoprecipitation (ChIP) coupled with quantitative PCR (qPCR) has in the last 15 years become a basic mainstream tool in genomic research. Numerous commercially available ChIP kits, qPCR kits, and real-time PCR systems allow for quick and easy analysis of virtually anything chromatin-related as long as there is an available antibody. However, the highly accurate quantitative dimension added by using qPCR to analyze ChIP samples significantly raises the bar in terms of experimental accuracy, appropriate controls, data analysis, and data presentation. This chapter will address these potential pitfalls by providing protocols and procedures that address the difficulties inherent in ChIP-qPCR assays.

  7. The ChArMEx database

    NASA Astrophysics Data System (ADS)

    Ferré, Helene; Belmahfoud, Nizar; Boichard, Jean-Luc; Brissebrat, Guillaume; Descloitres, Jacques; Fleury, Laurence; Focsa, Loredana; Henriot, Nicolas; Mastrorillo, Laurence; Mière, Arnaud; Vermeulen, Anne

    2014-05-01

    The Chemistry-Aerosol Mediterranean Experiment (ChArMEx, http://charmex.lsce.ipsl.fr/) aims at a scientific assessment of the present and future state of the atmospheric environment in the Mediterranean Basin, and of its impacts on the regional climate, air quality, and marine biogeochemistry. The project includes long term monitoring of environmental parameters, intensive field campaigns, use of satellite data and modelling studies. Therefore ChARMEx scientists produce and need to access a wide diversity of data. In this context, the objective of the database task is to organize data management, distribution system and services, such as facilitating the exchange of information and stimulating the collaboration between researchers within the ChArMEx community, and beyond. The database relies on a strong collaboration between OMP and ICARE data centres and has been set up in the framework of the Mediterranean Integrated Studies at Regional And Locals Scales (MISTRALS) program data portal. All the data produced by or of interest for the ChArMEx community will be documented in the data catalogue and accessible through the database website: http://mistrals.sedoo.fr/ChArMEx. At present, the ChArMEx database contains about 75 datasets, including 50 in situ datasets (2012 and 2013 campaigns, Ersa background monitoring station), 25 model outputs (dust model intercomparison, MEDCORDEX scenarios), and a high resolution emission inventory over the Mediterranean. Many in situ datasets have been inserted in a relational database, in order to enable more accurate data selection and download of different datasets in a shared format. The database website offers different tools: - A registration procedure which enables any scientist to accept the data policy and apply for a user database account. - A data catalogue that complies with metadata international standards (ISO 19115-19139; INSPIRE European Directive; Global Change Master Directory Thesaurus). - Metadata forms to document

  8. VU6010608, a Novel mGlu7 NAM from a Series of N-(2-(1H-1,2,4-Triazol-1-yl)-5-(trifluoromethoxy)phenyl)benzamides.

    PubMed

    Reed, Carson W; McGowan, Kevin M; Spearing, Paul K; Stansley, Branden J; Roenfanz, Hanna F; Engers, Darren W; Rodriguez, Alice L; Engelberg, Eileen M; Luscombe, Vincent B; Loch, Matthew T; Remke, Daniel H; Rook, Jerri M; Blobaum, Anna L; Conn, P Jeffrey; Niswender, Colleen M; Lindsley, Craig W

    2017-12-14

    Herein, we report the structure-activity relationships within a series of mGlu 7 NAMs based on an N -(2-(1 H -1,2,4-triazol-1-yl)-5-(trifluoromethoxy)phenyl)benzamide core with excellent CNS penetration ( K p 1.9-5.8 and K p,uu 0.4-1.4). Analogues in this series displayed steep SAR. Of these, VU6010608 ( 11a ) emerged with robust efficacy in blocking high frequency stimulated long-term potentiation in electrophysiology studies.

  9. Rate coefficients for the gas-phase reaction of the hydroxyl radical with CH2=CHF and CH2=CF2.

    PubMed

    Baasandorj, Munkhbayar; Knight, Gary; Papadimitriou, Vassileios C; Talukdar, Ranajit K; Ravishankara, A R; Burkholder, James B

    2010-04-08

    Rate coefficients, k, for the gas-phase reaction of the OH radical with CH(2)=CHF (k(1)) and CH(2)=CF(2) (k(2)) were measured under pseudo-first-order conditions in OH using pulsed laser photolysis to produce OH and laser-induced fluorescence (PLP-LIF) to detect it. Rate coefficients were measured over a range of temperature (220-373 K) and bath gas pressure (20-600 Torr; He, N(2)). The rate coefficients were found to be independent of pressure. The measured rate coefficient for reaction 1 at room temperature was k(1)(296 K) = (5.18 +/- 0.50) x 10(-12) cm(3) molecule(-1) s(-1), independent of pressure, and the temperature dependence is given by the Arrhenius expression k(1)(T) = (1.75 +/- 0.20) x 10(-12) exp[(316 +/- 25)/T] cm(3) molecule(-1) s(-1); the rate coefficients for reaction 2 were k(2)(296 K) = (2.79 +/- 0.25) x 10(-12) cm(3) molecule(-1) s(-1) and k(2)(T) = (1.75 +/- 0.20) x 10(-12) exp[(140 +/- 20)/T] cm(3) molecule(-1) s(-1). The quoted uncertainties are 2sigma (95% confidence level) and include estimated systematic errors. The fall-off parameters for reaction 2 of k(infinity) = 3 x 10(-12) cm(3) molecule(-1) s(-1) and k(0)(296 K) = 1.8 x 10(-28) cm(6) molecule(-2) s(-1) with F(c) = 0.6 reproduce the room temperature data obtained in this study combined with the low pressure rate coefficient data from Howard (J. Chem. Phys. 1976, 65, 4771). OH radical formation was observed for reactions 1 and 2 in the presence of O(2), and the mechanism was investigated using (18)OH and OD rate coefficient measurements with CH(2)=CHF and CH(2)=CF(2) over a range of temperature (260-373 K) and pressure (20-100 Torr, He). Quantum chemical calculations using density functional theory (DFT) were used to determine the geometries and energies of the reactants and adducts formed in reactions 1 and 2 and the peroxy radicals formed following the addition of O(2). The atmospheric lifetimes of CH(2)=CHF and CH(2)=CF(2) due to loss by reaction with OH are approximately 2 and 4

  10. Chemical and isotopic equilibrium between CO 2 and CH 4 in fumarolic gas discharges: Generation of CH 4 in arc magmatic-hydrothermal systems

    NASA Astrophysics Data System (ADS)

    Fiebig, Jens; Chiodini, Giovanni; Caliro, Stefano; Rizzo, Andrea; Spangenberg, Jorge; Hunziker, Johannes C.

    2004-05-01

    The chemical and isotopic composition of fumarolic gases emitted from Nisyros Volcano, Greece, and of a single gas sample from Vesuvio, Italy, was investigated in order to determine the origin of methane (CH 4) within two subduction-related magmatic-hydrothermal environments. Apparent temperatures derived from carbon isotope partitioning between CH 4 and CO 2 of around 340°C for Nisyros and 470°C for Vesuvio correlate well with aquifer temperatures as measured directly and/or inferred from compositional data using the H 2O-H 2-CO 2-CO-CH 4 geothermometer. Thermodynamic modeling reveals chemical equilibrium between CH 4, CO 2 and H 2O implying that carbon isotope partitioning between CO 2 and CH 4 in both systems is controlled by aquifer temperature. N 2/ 3He and CH 4/ 3He ratios of Nisyros fumarolic gases are unusually low for subduction zone gases and correspond to those of midoceanic ridge environments. Accordingly, CH 4 may have been primarily generated through the reduction of CO 2 by H 2 in the absence of any organic matter following a Fischer-Tropsch-type reaction. However, primary occurrence of minor amounts of thermogenic CH 4 and subsequent re-equilibration with co-existing CO 2 cannot be ruled out entirely. CO 2/ 3He ratios and δ 13C CO 2 values imply that the evolved CO 2 either derives from a metasomatized mantle or is a mixture between two components, one outgassing from an unaltered mantle and the other released by thermal breakdown of marine carbonates. The latter may contain traces of organic matter possibly decomposing to CH 4 during thermometamorphism.

  11. The First Laboratory Detection of Vibration-rotation Transitions of 12CH+ and 13CH+ and Improved Measurement of Their Rotational Transition Frequencies

    NASA Astrophysics Data System (ADS)

    Doménech, José L.; Jusko, Pavol; Schlemmer, Stephan; Asvany, Oskar

    2018-04-01

    C–H stretches of the fundamental ions CH+ and 13CH+, which have long been searched for, have been observed for the first time in the laboratory. The state-dependent attachment of He atoms to these ions at cryogenic temperatures has been exploited to obtain high-resolution rovibrational data. In addition, the lowest rotational transitions of CH+, 13CH+ and CD+ have been revisited and their rest frequency values have improved substantially.

  12. G331.512–0.103: An Interstellar Laboratory for Molecular Synthesis. I. The Ortho-to-para Ratios for CH3OH and CH3CN

    NASA Astrophysics Data System (ADS)

    Mendoza, Edgar; Bronfman, Leonardo; Duronea, Nicolas U.; Lépine, Jacques R. D.; Finger, Ricardo; Merello, Manuel; Hervías-Caimapo, Carlos; Gama, Diana R. G.; Reyes, Nicolas; Åke-Nyman, Lars

    2018-02-01

    Spectral line surveys reveal rich molecular reservoirs in G331.512–0.103, a compact radio source in the center of an energetic molecular outflow. In this first work, we analyze the physical conditions of the source by means of CH3OH and CH3CN. The observations were performed with the APEX Telescope. Six different system configurations were defined to cover most of the band within (292–356) GHz as a consequence, we detected a forest of lines toward the central core. A total of 70 lines of A/E–CH3OH and A/E–CH3CN were analyzed, including torsionally excited transitions of CH3OH ({ν }t=1). In a search for all the isotopologues, we identified transitions of 13CH3OH. The physical conditions were derived considering collisional and radiative processes. We found common temperatures for each A and E symmetry of CH3OH and CH3CN; the derived column densities indicate an A/E equilibrated ratio for both tracers. The results reveal that CH3CN and CH3OH trace a hot and cold component with {T}k∼ 141 K and {T}k∼ 74 K, respectively. In agreement with previous ALMA observations, the models show that the emission region is compact (≲ 5\\buildrel{\\prime\\prime}\\over{.} 5) with gas density n(H2) = (0.7–1)×107 cm‑3. The CH3OH/CH3CN abundance ratio and the evidences for prebiotic and complex organic molecules suggest a rich and active chemistry toward G331.512–0.103.

  13. A new method for speciated CH3O2 radical detection and HIRAC (Highly Instrumented Reactor for Atmospheric Chemistry) studies of the CH3O2 self-reaction

    NASA Astrophysics Data System (ADS)

    Onel, Lavinia; Brennan, Alexander; Seakins, Paul W.; Whalley, Lisa; Heard, Dwayne

    2016-04-01

    A new method has been developed for the speciated detection of CH3O2 radicals by FAGE (Fluorescence Assay by Gas Expansion) by titrating CH3O2 to CH3O by reaction with added NO and then detecting the resultant CH3O by LIF (laser induced fluorescence). The limit of detection of the technique is ˜108 cm-3 CH3O2 for a unity signal-to-noise ratio and 5 min averaging time. The method has been used for time monitoring of CH3O2 during its self-reaction within HIRAC at 1 bar and room temperature to determine a preliminary value of the rate coefficient of 4.2 × 10-13 cm3 s-1, which lies in the range of the previous results, (2.7 - 5.2) × 10-13 cm3 s-1.1 In addition to detection of CH3O2, products of the CH3O2 self-reaction were also observed for the two reaction channels over a range of temperatures from 260 - 320 K: (a) 2CH3O2 → CH2O + CH3OH; (b) 2CH3O2 → 2CH3O + O2, namely HO2 radicals (from reaction of CH3O + O2) and formaldehyde monitored by FAGE and formaldehyde and methanol observed by FTIR. A good agreement has been obtained between the FTIR and FAGE measurements of CH2O which increased to ˜ 2 ppmv over the experiments. Using the concentrations of CH3OH and CH2O, the branching ratio for channel (a) at room temperature has been determined as ra = 0.66 ± 0.06. The result is in very good agreement with the value recommended in the review of Tyndall et al.2 of ra = 0.63 ± 0.06. No temperature dependence of ra has been observed from 296 K to 321 K. 1. http://iupac.pole-ether.fr/ 2. G. S. Tyndall et al., J. Geophys. Res. 106, 12157 (2001).

  14. Crystal and molecular structure of the first dibino non-geminal macrocyclic dicyclophosphazene, & {;N 3P 3Cl 4[HN(CH 2) 3O(CH 2) 2O(CH 2) 3NH]&}; 2

    NASA Astrophysics Data System (ADS)

    Enjalbert, Renée; Galy, Jean; Sournies, François; Labarre, Jean-François

    1990-04-01

    Reaction of N 3P 3Cl 6 with the 4,7-dioxadecane-1,10-diamine (coded as 3O2O3) using an Et 2O/Na 2CO 3 water interface process leads to the DIBINO non-geminal 30-membered macrocyclic dicyclophosphazene &{;N 3P 3Cl 4[HN(CH 2) 3O(CH 2) 2O(CH 2) 3NH]&}; 2. This 30-crown-ether-like architecture crystallizes in the triclinic system, P1, a=9.019(6), b=9.224(5), c=11.542(8) Å, α=94.87(4), β=95.97(4), γ=99.68(3)°, V=936(1) Å 3, Dx=1.599 Mg m -3, R=0.049 for 2862 unique reflections and 199 variable parameters. The structure exhibits a spatial arrangement of two N 3P 3Cl 4 with two [HN(CH 2) 3O(CH 2) 3O(CH 2) 3NH] as bridges on different P atoms of N 3P 3 rings. Moreover, the two N 3P 3 rings are trans to the average plane of the 30-membered macrocycle ("chair" conformation).

  15. Coupled potential energy surface for the F(2P)+CH4→HF+CH3 entrance channel and quantum dynamics of the CH4·F- photodetachment.

    PubMed

    Westermann, Till; Eisfeld, Wolfgang; Manthe, Uwe

    2013-07-07

    An approach to construct vibronically and spin-orbit coupled diabatic potential energy surfaces (PESs) which describe all three relevant electronic states in the entrance channels of the X(P) + CH4 →HX + CH3 reactions (with X=F((2)P), Cl((2)P), or O((3)P)) is introduced. The diabatization relies on the permutational symmetry present in the methane molecule and results in diabatic states which transform as the three p orbitals of the X atom. Spin-orbit coupling is easily and accurately included using the atomic spin-orbit coupling matrix of the isolated X atom. The method is applied to the F + CH4 system obtaining an accurate PES for the entrance channel based on ab initio multi-reference configuration interaction (MRCI) calculations. Comparing the resulting PESs with spin-orbit MRCI calculations, excellent agreement is found for the excited electronic states at all relevant geometries. The photodetachment spectrum of CH4·F(-) is investigated via full-dimensional (12D) quantum dynamics calculations on the coupled PESs using the multi-layer multi-configurational time-dependent Hartree approach. Extending previous work [J. Palma and U. Manthe, J. Chem. Phys. 137, 044306 (2012)], which was restricted to the dynamics on a single adiabatic PES, the contributions of the electronically excited states to the photodetachment spectrum are calculated and compared to experiment. Considering different experimental setups, good agreement between experiment and theory is found. Addressing questions raised in the previous work, the present dynamical calculations show that the main contribution to the second peak in the photodetachment spectrum results from electron detachment into the electronically excited states of the CH4F complex.

  16. Forty women parliamentarians gather to reaffirm commitment to the ICPD, Ho Chi Minh City, Viet Nam.

    PubMed

    1995-01-01

    Over 40 delegates attended the Indo-China Female Parliamentarians Conference on the Status of Women and Reproductive Health held in Viet Nam in June 1995. The conference was organized by the Vietnamese Association of Parliamentarians on Population and Development. Participants noted that, in Indochina, the participation of women in local politics has been blocked by the absence of laws and policies on gender equality. Recommended, to remedy this situation, were the following measures: 1) implementation of programs on women's status outlined at the 1994 International Conference on Population and Development; 2) allocation of sufficient resources for programs in the areas of maternal-child health, family planning, and acquired immunodeficiency syndrome (AIDS) prevention; 3) enactment of laws banning child prostitution and violence against women; 4) promotion of changes in men's sexual behaviors that spread AIDS; 5) encouragement of women to increase their knowledge of and participation in political action; and 6) appeals to international agencies and nongovernmental organizations to develop programs for Indochinese women.

  17. Reactivity of OH and CH3OH Between 22 and 64 K: Modelling the Gas Phase Production of CH3O in Barnard 1B

    PubMed Central

    Antiñolo, M.; Agúndez, M.; Jiménez, E.; Ballesteros, B.; Canosa, A.; Dib, G. El; Albaladejo, J.; Cernicharo, J.

    2016-01-01

    In the last years, ultra-low temperature chemical kinetic experiments have demonstrated that some gas-phase reactions are much faster than previously thought. One example is the reaction between OH and CH3OH, which has been recently found to be accelerated at low temperatures yielding CH3O as main product. This finding opened the question of whether the CH3O observed in the dense core Barnard 1b could be formed by the gas-phase reaction of CH3OH and OH. Several chemical models including this reaction and grain-surface processes have been developed to explain the observed abundance of CH3O with little success. Here we report for the first time rate coefficients for the gas-phase reaction of OH and CH3OH down to a temperature of 22 K, very close to those in cold interstellar clouds. Two independent experimental set-ups based on the supersonic gas expansion technique coupled to the pulsed laser photolysis-laser induced fluorescence technique were used to determine rate coefficients in the temperature range 22-64 K. The temperature dependence obtained in this work can be expressed as k(22-64 K) = (3.6 ± 0.1) × 10−12(T/300 K)−(1.0±0.2) cm3 molecule−1 s−1. Implementing this expression in a chemical model of a cold dense cloud results in CH3O/CH3OH abundance ratios similar or slightly lower than the value of ∼ 3 × 10−3 observed in Barnard 1b. This finding confirms that the gas-phase reaction between OH and CH3OH is an important contributor to the formation of interstellar CH3O. The role of grain-surface processes in the formation of CH3O, although it cannot be fully neglected, remains controversial. PMID:27279655

  18. Reactivity of OH and CH3OH Between 22 and 64 K: Modelling the Gas Phase Production of CH3O in Barnard 1B.

    PubMed

    Antiñolo, M; Agúndez, M; Jiménez, E; Ballesteros, B; Canosa, A; Dib, G El; Albaladejo, J; Cernicharo, J

    2016-05-20

    In the last years, ultra-low temperature chemical kinetic experiments have demonstrated that some gas-phase reactions are much faster than previously thought. One example is the reaction between OH and CH 3 OH, which has been recently found to be accelerated at low temperatures yielding CH 3 O as main product. This finding opened the question of whether the CH 3 O observed in the dense core Barnard 1b could be formed by the gas-phase reaction of CH 3 OH and OH. Several chemical models including this reaction and grain-surface processes have been developed to explain the observed abundance of CH 3 O with little success. Here we report for the first time rate coefficients for the gas-phase reaction of OH and CH 3 OH down to a temperature of 22 K, very close to those in cold interstellar clouds. Two independent experimental set-ups based on the supersonic gas expansion technique coupled to the pulsed laser photolysis-laser induced fluorescence technique were used to determine rate coefficients in the temperature range 22-64 K. The temperature dependence obtained in this work can be expressed as k (22-64 K) = (3.6 ± 0.1) × 10 -12 ( T/ 300 K) -(1.0±0.2) cm 3 molecule -1 s -1 . Implementing this expression in a chemical model of a cold dense cloud results in CH 3 O/CH 3 OH abundance ratios similar or slightly lower than the value of ∼ 3 × 10 -3 observed in Barnard 1b. This finding confirms that the gas-phase reaction between OH and CH 3 OH is an important contributor to the formation of interstellar CH 3 O. The role of grain-surface processes in the formation of CH 3 O, although it cannot be fully neglected, remains controversial.

  19. The Structure of Titan’s N2 and CH4 Coronae

    NASA Astrophysics Data System (ADS)

    Jiang, Fayu; Cui, Jun; Xu, Jiyao

    2017-12-01

    In this study, we analyze the structures of Titan’s N2 and CH4 coronae using a large data set acquired by the Ion Neutral Mass Spectrometer (INMS) instrument on board Cassini. The N2 and CH4 densities measured from the exobase up to 2000 km imply a mean exobase temperature of 146 K and 143 K, respectively, which is lower than the mean upper atmospheric temperature by 4 and 7 K. This indicates that on average, Titan possesses a subthermal rather than suprathermal corona. A careful examination reveals that the variability in corona structure is not very likely to be solar driven. Within the framework of the collisionless kinetic model, we investigate how the CH4 energy distribution near the exobase could be constrained if strong CH4 escape occurs on Titan. Several functional forms for the CH4 energy distribution are attempted, assuming two representative CH4 escape rates of 1.2× {10}25 s-1 and 2.2× {10}27 s-1. We find that the double Maxwellian and power-law distributions can reproduce the shape of the CH4 corona structure as well as the imposed CH4 escape rate. In both cases, the escape rate is contributed by a suprathermal CH4 population on the high-energy tail, with a number fraction below 5% and a characteristic energy of 0.1-0.6 eV per suprathermal CH4 molecule. The coexistence of the subthermal CH4 corona revealed by the INMS data and substantial CH4 escape suggested by some previous works could be reconciled by a significant departure in the exobase CH4 energy distribution from ideal Maxwellian that enhances escape and causes a noticeable redistribution of the corona structure.

  20. The relative abundances of resolved l2CH2D2 and 13CH3D and mechanisms controlling isotopic bond ordering in abiotic and biotic methane gases

    NASA Astrophysics Data System (ADS)

    Young, E. D.; Kohl, I. E.; Lollar, B. Sherwood; Etiope, G.; Rumble, D.; Li, S.; Haghnegahdar, M. A.; Schauble, E. A.; McCain, K. A.; Foustoukos, D. I.; Sutclife, C.; Warr, O.; Ballentine, C. J.; Onstott, T. C.; Hosgormez, H.; Neubeck, A.; Marques, J. M.; Pérez-Rodríguez, I.; Rowe, A. R.; LaRowe, D. E.; Magnabosco, C.; Yeung, L. Y.; Ash, J. L.; Bryndzia, L. T.

    2017-04-01

    We report measurements of resolved 12CH2D2 and 13CH3D at natural abundances in a variety of methane gases produced naturally and in the laboratory. The ability to resolve 12CH2D2 from 13CH3D provides unprecedented insights into the origin and evolution of CH4. The results identify conditions under which either isotopic bond order disequilibrium or equilibrium are expected. Where equilibrium obtains, concordant Δ12CH2D2 and Δ13CH3D temperatures can be used reliably for thermometry. We find that concordant temperatures do not always match previous hypotheses based on indirect estimates of temperature of formation nor temperatures derived from CH4/H2 D/H exchange, underscoring the importance of reliable thermometry based on the CH4 molecules themselves. Where Δ12CH2D2 and Δ13CH3D values are inconsistent with thermodynamic equilibrium, temperatures of formation derived from these species are spurious. In such situations, while formation temperatures are unavailable, disequilibrium isotopologue ratios nonetheless provide novel information about the formation mechanism of the gas and the presence or absence of multiple sources or sinks. In particular, disequilibrium isotopologue ratios may provide the means for differentiating between methane produced by abiotic synthesis vs. biological processes. Deficits in 12CH2D2 compared with equilibrium values in CH4 gas made by surface-catalyzed abiotic reactions are so large as to point towards a quantum tunneling origin. Tunneling also accounts for the more moderate depletions in 13CH3D that accompany the low 12CH2D2 abundances produced by abiotic reactions. The tunneling signature may prove to be an important tracer of abiotic methane formation, especially where it is preserved by dissolution of gas in cool hydrothermal systems (e.g., Mars). Isotopologue signatures of abiotic methane production can be erased by infiltration of microbial communities, and Δ12CH2D2 values are a key tracer of microbial recycling.

  1. Chromatin Immunoprecipitation (ChIP) Protocol for Low-abundance Embryonic Samples.

    PubMed

    Rehimi, Rizwan; Bartusel, Michaela; Solinas, Francesca; Altmüller, Janine; Rada-Iglesias, Alvaro

    2017-08-29

    Chromatin immunoprecipitation (ChIP) is a widely-used technique for mapping the localization of post-translationally modified histones, histone variants, transcription factors, or chromatin-modifying enzymes at a given locus or on a genome-wide scale. The combination of ChIP assays with next-generation sequencing (i.e., ChIP-Seq) is a powerful approach to globally uncover gene regulatory networks and to improve the functional annotation of genomes, especially of non-coding regulatory sequences. ChIP protocols normally require large amounts of cellular material, thus precluding the applicability of this method to investigating rare cell types or small tissue biopsies. In order to make the ChIP assay compatible with the amount of biological material that can typically be obtained in vivo during early vertebrate embryogenesis, we describe here a simplified ChIP protocol in which the number of steps required to complete the assay were reduced to minimize sample loss. This ChIP protocol has been successfully used to investigate different histone modifications in various embryonic chicken and adult mouse tissues using low to medium cell numbers (5 x 10 4 - 5 x 10 5 cells). Importantly, this protocol is compatible with ChIP-seq technology using standard library preparation methods, thus providing global epigenomic maps in highly relevant embryonic tissues.

  2. Temperature-Dependent Kinetics Studies of the Reactions Br((sup 2)P(sub 3/2)) + CH3SCH3 reversible reaction CH3SCH2 + HBr. Heat of Formation of the CH3SCH2 Radical

    NASA Technical Reports Server (NTRS)

    Jefferson, A.; Nicovich, J. M.; Wine, P. H.

    1997-01-01

    Time-resolved resonance fluorescence detection of Br((sup 2)P(sub 3/2)) atom disappearance or appearance 266 nm laser flash photolysis of CF2Br2/CH3SCH3/H2/N2 and Cl2CO/CH2SCH3/HBr/H2/N2 mixtures has been employed to study the kinetics of the reactions Br((sup 2)P(sub 3/2)) + CH3SCH3 reversible reaction HBr + CH3SCH2 (1,-1) as a function of temperature over the range 386-604 K. Arrhenius expressions in units of cu cm/molecule which describe the results are k3= (9.0 +/- 2.9) x 10 (exp -11) exp[(-2386 +/- 151)/T]; errors are 2 sigma and represent precision only. To our knowledge, these are the first kinetic data reported for each of the two reactions studied. Second and third law analyses of the equilibrium data for reactions 1 and -1 have been employed to obtain the following enthalpies of reaction in units of kcal/mol: Delta-H(298) = 6.11 +/- 1.37 and Delta-H(0) = 5.37 +/- 1.38. Combining the above enthalpies of reaction with the well-known heats of formation of Br, HBr, CH3SCH3 gives the following heats of formation of the CH3SCH2 radical in units of kcal/mol: Delta-H(sub(f,298)) = 32.7 +/- 1.4 and Delta-H(sub (f,0)) = 35.3 +/- 1.4; errors are 2 sigma and represent estimates of absolute accuracy. The C-H bond dissociation energy in CH3SCH3 obtained from our data, 93.7 +/- 1.4 kcal/mol at 298 K and 92.0 +/- 1.4 kcal at 0 k, agrees well with a recent molecular beam photofragmentaion study but is 3 kcal/mol lower than the value obtained from an iodination kinetics study.

  3. GIS and local knowledge in disaster management: a case study of flood risk mapping in Viet Nam.

    PubMed

    Tran, Phong; Shaw, Rajib; Chantry, Guillaume; Norton, John

    2009-03-01

    Linking community knowledge with modern techniques to record and analyse risk related data is one way of engaging and mobilising community capacity. This paper discusses the use of the Geographic Information System (GIS) at the local level and the need for integrating modern technology and indigenous knowledge into disaster management. It suggests a way to mobilise available human and technical resources in order to strengthen a good partnership between local communities and local and national institutions. The paper also analyses the current vulnerability of two communes by correlating hazard risk and loss/damage caused by disasters and the contribution that domestic risk maps in the community can make to reduce this risk. The disadvantages, advantages and lessons learned from the GIS flood risk mapping project are presented through the case study of the Quang Tho Commune in Thua Thien Hue province, central Viet Nam.

  4. Enhanced Performance of Perovskite CH3NH3PbI3 Solar Cell by Using CH3NH3I as Additive in Sequential Deposition.

    PubMed

    Xie, Yian; Shao, Feng; Wang, Yaoming; Xu, Tao; Wang, Deliang; Huang, Fuqiang

    2015-06-17

    Sequential deposition is a widely adopted method to prepare CH3NH3PbI3 on mesostructured TiO2 electrode for organic lead halide perovskite solar cells. However, this method often suffers from the uncontrollable crystal size, surface morphology, and residual PbI2 in the resulting CH3NH3PbI3, which are all detrimental to the device performance. We herein present an optimized sequential solution deposition method by introducing different amount of CH3NH3I in PbI2 precursor solution in the first step to prepare CH3NH3PbI3 absorber on mesoporous TiO2 substrates. The addition of CH3NH3I in PbI2 precursor solution can affect the crystallization and composition of PbI2 raw films, resulting in the variation of UV-vis absorption and surface morphology. Proper addition of CH3NH3I not only enhances the absorption but also improves the efficiency of CH3NH3PbI3 solar cells from 11.13% to 13.37%. Photoluminescence spectra suggest that the improvement of device performance is attributed to the decrease of recombination rate of carriers in CH3NH3PbI3 absorber. This current method provides a highly repeatable route for enhancing the efficiency of CH3NH3PbI3 solar cell in the sequential solution deposition method.

  5. Evaluation of global horizontal irradiance to plane-of-array irradiance models at locations across the United States

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

    Lave, Matthew; Hayes, William; Pohl, Andrew

    2015-02-02

    We report an evaluation of the accuracy of combinations of models that estimate plane-of-array (POA) irradiance from measured global horizontal irradiance (GHI). This estimation involves two steps: 1) decomposition of GHI into direct and diffuse horizontal components and 2) transposition of direct and diffuse horizontal irradiance (DHI) to POA irradiance. Measured GHI and coincident measured POA irradiance from a variety of climates within the United States were used to evaluate combinations of decomposition and transposition models. A few locations also had DHI measurements, allowing for decoupled analysis of either the decomposition or the transposition models alone. Results suggest that decompositionmore » models had mean bias differences (modeled versus measured) that vary with climate. Transposition model mean bias differences depended more on the model than the location. Lastly, when only GHI measurements were available and combinations of decomposition and transposition models were considered, the smallest mean bias differences were typically found for combinations which included the Hay/Davies transposition model.« less

  6. Relative Importance of Different Attributes of Graphic Health Warnings on Tobacco Packages in Viet Nam.

    PubMed

    Giang, Kim Bao; Chung, Le Hong; Minh, Hoang Van; Kien, Vu Duy; Giap, Vu Van; Hinh, Nguyen Duc; Cuong, Nguyen Manh; Manh, Pham Duc; Duc, Ha Anh; Yang, Jui-Chen

    2016-01-01

    Graphic health warnings (GHW) on tobacco packages have proven to be effective in increasing quit attempts among smokers and reducing initial smoking among adolescents. This research aimed to examine the relative importance of different attributes of graphic health warnings on tobacco packages in Viet Nam. A discrete choice experimental (DCE) design was applied with a conditional logit model. In addition, a ranking method was used to list from the least to the most dreadful GHW labels. With the results from DCE model, graphic type was shown to be the most important attribute, followed by cost and coverage area of GHW. The least important attribute was position of the GHW. Among 5 graphic types (internal lung cancer image, external damaged teeth, abstract image, human suffering image and text), the image of lung cancer was found to have the strongest influence on both smokers and non-smokers. With ranking method, the image of throat cancer and heart diseases were considered the most dreadful images. GHWs should be designed with these attributes in mind, to maximise influence on purchase among both smokers and non-smokers.

  7. A comparative DFT study of interactions of Au and small gold clusters Aun (n = 2-4) with CH3S and CH2 radicals

    NASA Astrophysics Data System (ADS)

    Blaško, Martin; Rajský, Tomáš; Urban, Miroslav

    2017-03-01

    We compare DFT binding energies (BEs) of Au and small gold clusters interacting with CH3S and CH2 ligands (Aun-L complexes, n = 1-4). The spin state and the binding mechanism in Aun-L varies with the participation of singly occupied non-bonding orbitals or doubly occupied lone-pair orbitals of a ligand and on the number of atoms (even or odd) of Aun. The highest BE, 354 kJ/mol, exhibits the Au3-CH2 complex with the covalent bond in which participate two singly occupied orbitals of the triplet state of CH2. With CH3S the highest BE (277 kJ/mol) is calculated for Au3-SCH3 with the single Au-S bond.

  8. Relativistic GW calculations on CH3NH3PbI3 and CH3NH3SnI3 perovskites for solar cell applications.

    PubMed

    Umari, Paolo; Mosconi, Edoardo; De Angelis, Filippo

    2014-03-26

    Hybrid AMX3 perovskites (A = Cs, CH3NH3; M = Sn, Pb; X = halide) have revolutionized the scenario of emerging photovoltaic technologies, with very recent results demonstrating 15% efficient solar cells. The CH3NH3PbI3/MAPb(I(1-x)Cl(x))3 perovskites have dominated the field, while the similar CH3NH3SnI3 has not been exploited for photovoltaic applications. Replacement of Pb by Sn would facilitate the large uptake of perovskite-based photovoltaics. Despite the extremely fast progress, the materials electronic properties which are key to the photovoltaic performance are relatively little understood. Density Functional Theory electronic structure methods have so far delivered an unbalanced description of Pb- and Sn-based perovskites. Here we develop an effective GW method incorporating spin-orbit coupling which allows us to accurately model the electronic, optical and transport properties of CH3NH3SnI3 and CH3NH3PbI3, opening the way to new materials design. The different CH3NH3SnI3 and CH3NH3PbI3 electronic properties are discussed in light of their exploitation for solar cells, and found to be dominantly due to relativistic effects. These effects stabilize the CH3NH3PbI3 material towards oxidation, by inducing a deeper valence band edge. Relativistic effects, however, also increase the material band-gap compared to CH3NH3SnI3, due to the valence band energy downshift (~0.7 eV) being only partly compensated by the conduction band downshift (~0.2 eV).

  9. Relativistic GW calculations on CH3NH3PbI3 and CH3NH3SnI3 Perovskites for Solar Cell Applications

    PubMed Central

    Umari, Paolo; Mosconi, Edoardo; De Angelis, Filippo

    2014-01-01

    Hybrid AMX3 perovskites (A = Cs, CH3NH3; M = Sn, Pb; X = halide) have revolutionized the scenario of emerging photovoltaic technologies, with very recent results demonstrating 15% efficient solar cells. The CH3NH3PbI3/MAPb(I1−xClx)3 perovskites have dominated the field, while the similar CH3NH3SnI3 has not been exploited for photovoltaic applications. Replacement of Pb by Sn would facilitate the large uptake of perovskite-based photovoltaics. Despite the extremely fast progress, the materials electronic properties which are key to the photovoltaic performance are relatively little understood. Density Functional Theory electronic structure methods have so far delivered an unbalanced description of Pb- and Sn-based perovskites. Here we develop an effective GW method incorporating spin-orbit coupling which allows us to accurately model the electronic, optical and transport properties of CH3NH3SnI3 and CH3NH3PbI3, opening the way to new materials design. The different CH3NH3SnI3 and CH3NH3PbI3 electronic properties are discussed in light of their exploitation for solar cells, and found to be dominantly due to relativistic effects. These effects stabilize the CH3NH3PbI3 material towards oxidation, by inducing a deeper valence band edge. Relativistic effects, however, also increase the material band-gap compared to CH3NH3SnI3, due to the valence band energy downshift (~0.7 eV) being only partly compensated by the conduction band downshift (~0.2 eV). PMID:24667758

  10. Exploring the Reactivity Trends in the E2 and SN2 Reactions of X(-) + CH3CH2Cl (X = F, Cl, Br, HO, HS, HSe, NH2 PH2, AsH2, CH3, SiH3, and GeH3).

    PubMed

    Wu, Xiao-Peng; Sun, Xiao-Ming; Wei, Xi-Guang; Ren, Yi; Wong, Ning-Bew; Li, Wai-Kee

    2009-06-09

    The reactivity order of 12 anions toward ethyl chloride has been investigated by using the G2(+) method, and the competitive E2 and SN2 reactions are discussed and compared. The reactions studied are X(-) + CH3CH2Cl → HX + CH2═CH2 + Cl(-) and X(-) + CH3CH2Cl → CH3CH2X + Cl(-), with X = F, Cl, Br, HO, HS, HSe, NH2 PH2, AsH2, CH3, SiH3, and GeH3. Our results indicate that there is no general and straightforward relationship between the overall barriers and the proton affinity (PA) of X(-); instead, discernible linear correlations only exist for the X's within the same group of the periodic table. Similar correlations are also found with the electronegativity of central atoms in X, deformation energy of the E2 transition state (TS), and the overall enthalpy of reaction. It is revealed that the electronegativity will significantly affect the barrier height, and a more electronegative X will stabilize the E2 and SN2 transition states. Multiple linear regression analysis shows that there is a reasonable linear correlation between E2 (or SN2) overall barriers and the linear combination of PA of X(-) and electronegativity of the central atom.

  11. Genetic characterisation of a cohort of children clinically labelled as GH or IGF1 insensitive: diagnostic value of serum IGF1 and height at presentation.

    PubMed

    Storr, Helen L; Dunkel, Leo; Kowalczyk, Julia; Savage, Martin O; Metherell, Louise A

    2015-02-01

    GH insensitivity (GHI) encompasses growth failure, low serum IGF1 and normal/elevated serum GH. By contrast, IGF1 insensitivity results in pre- and postnatal growth failure associated with relatively high IGF1 levels. From 2008 to 2013, 72 patients from 68 families (45M), mean age 7.1 years (0.4-17.0) with short stature (mean height SDS -3.9; range -9.4 to -1.5), were referred for sequencing. As a genetics referral centre, we have sequenced appropriate candidate genes (GHR, including its pseudoexon (6Ψ), STAT5B, IGFALS, IGF1, IGF1R, OBSL1, CUL7 and CCDC8) in subjects referred with suspected GHI (n=69) or IGF1 insensitivity (n=3). Mean serum IGF1 SDS was -2.7 (range -0.9 to -8.2) in GHI patients and 2.0, 3.7 and 4.4 in patients with suspected IGF1 insensitivity. Out of 69 GHI patients, 16 (23%) (19% families) had mutations in GH-IGF1 axis genes: homozygous GHR (n=13; 6 6Ψ, two novel IVS5ds+1 G to A) and homozygous IGFALS (n=3; one novel c.1291delT). In the GHI groups, two homozygous OBSL1 mutations were also identified (height SDS -4.9 and -5.7) and two patients had hypomethylation in imprinting control region 1 in 11p15 or mUPD7 consistent with Silver-Russell syndrome (SRS) (height SDS -3.7 and -4.3). A novel heterozygous IGF1R (c.112G>A) mutation was identified in one out of three (33%) IGF1-insensitive subjects. Genotyping contributed to the diagnosis of children with suspected GHI and IGF1 insensitivity, particularly in the GHI subjects with low serum IGF1 SDS (<-2.0) and height SDS (<-2.5). Diagnoses with similar phenotypes included SRS and 3-M syndrome. In 71% patients, no diagnosis was defined justifying further genetic investigation. © 2015 European Society of Endocrinology.

  12. Polymeric Binders which Reversibly Dissociate at Elevated Temperatures

    DTIC Science & Technology

    1978-05-01

    C0O(CH2)xOC-C- N . ~Nk \\ N . N + H0(CH2)x OH HC. , , tH \\\\ N - N -C. HC-N1-- H H H ~0 ~+ 0CNRNC0 Polymer 14 S. Kasina and J. Nematollahi . "A New and Simple...NUMIIA& i* GOVT ACC9Ir.Q~ N NO. I CIIIIINT’S CATZALOG NUMOIR NWC-TP-591951 OLYUC INDERS WHICH.REVERSIBLY ! Rasear pr.. Ř 7.: , CISS-CIATSEAT ELEV...342M7RA""" El7cadUgee /nary.i TC. Aiea N - 3 F5335431. P ERMFORMING ORGANIZATION NAM E A NlO A OR SS 1 . P O R M CLM l T T S , ~ ~~~Naval Weapons

  13. ALMA Detection of Interstellar Methoxymethanol (CH3OCH2OH)

    NASA Astrophysics Data System (ADS)

    McGuire, Brett A.; Shingledecker, Christopher N.; Willis, Eric R.; Burkhardt, Andrew M.; El-Abd, Samer; Motiyenko, Roman A.; Brogan, Crystal L.; Hunter, Todd R.; Margulès, Laurent; Guillemin, Jean-Claude; Garrod, Robin T.; Herbst, Eric; Remijan, Anthony J.

    2017-12-01

    We report the detection of interstellar methoxymethanol (CH3OCH2OH) in Atacama Large Millimeter/submillimeter Array (ALMA) Bands 6 and 7 toward the MM1 core in the high-mass star-forming region NGC 6334I at ∼0.″1–1″ spatial resolution. A column density of 4(2) × 1018 cm‑2 at T ex = 200 K is derived toward MM1, ∼34 times less abundant than methanol (CH3OH), and significantly higher than predicted by astrochemical models. Probable formation and destruction pathways are discussed, primarily through the reaction of the CH3OH photodissociation products, the methoxy (CH3O) and hydroxymethyl (CH2OH) radicals. Finally, we comment on the implications of these mechanisms on gas-phase versus grain-surface routes operative in the region, and the possibility of electron-induced dissociation of CH3OH rather than photodissociation.

  14. Epidemiology, Seasonality, and Predictors of Outcome of AIDS-Associated Penicillium marneffei Infection in Ho Chi Minh City, Viet Nam

    PubMed Central

    Wolbers, Marcel; Quang, Vo Minh; Chinh, Nguyen Tran; Huong Lan, Nguyen Phu; Lam, Pham Si; Kozal, Michael J.; Shikuma, Cecilia M.; Day, Jeremy N.; Farrar, Jeremy

    2011-01-01

    Background. Penicillium marneffei is an important human immunodeficiency virus (HIV)–associated opportunistic pathogen in Southeast Asia. The epidemiology and the predictors of penicilliosis outcome are poorly understood. Methods. We performed a retrospective study of culture-confirmed incident penicilliosis admissions during 1996–2009 at the Hospital for Tropical Diseases in Ho Chi Minh City, Viet Nam. Seasonality of penicilliosis was assessed using cosinor models. Logistic regression was used to assess predictors of death or worsening disease based on 10 predefined covariates, and Cox regression was performed to model time-to-antifungal initiation. Results. A total of 795 patients were identified; hospital charts were obtainable for 513 patients (65%). Cases increased exponentially and peaked in 2007 (156 cases), mirroring the trends in AIDS admissions during the study period. A highly significant seasonality for penicilliosis (P < .001) but not for cryptococcosis (P = .63) or AIDS admissions (P = .83) was observed, with a 27% (95% confidence interval, 14%–41%) increase in incidence during rainy months. All patients were HIV infected; the median CD4 cell count (62 patients) was 7 cells/μL (interquartile range, 4–24 cells/μL). Hospital outcome was an improvement in 347 (68%), death in 101 (20%), worsening in 42 (8%), and nonassessable in 23 (5%) cases. Injection drug use, shorter history, absence of fever or skin lesions, elevated respiratory rates, higher lymphocyte count, and lower platelet count independently predicted poor outcome in both complete-case and multiple-imputation analyses. Time-to-treatment initiation was shorter for patients with skin lesions (hazard ratio, 3.78; 95% confidence interval, 2.96–4.84; P < .001). Conclusions. Penicilliosis incidence correlates with the HIV/AIDS epidemic in Viet nam. The number of cases increases during rainy months. Injection drug use, shorter history, absence of fever or skin

  15. ChIP-seq: advantages and challenges of a maturing technology.

    PubMed

    Park, Peter J

    2009-10-01

    Chromatin immunoprecipitation followed by sequencing (ChIP-seq) is a technique for genome-wide profiling of DNA-binding proteins, histone modifications or nucleosomes. Owing to the tremendous progress in next-generation sequencing technology, ChIP-seq offers higher resolution, less noise and greater coverage than its array-based predecessor ChIP-chip. With the decreasing cost of sequencing, ChIP-seq has become an indispensable tool for studying gene regulation and epigenetic mechanisms. In this Review, I describe the benefits and challenges in harnessing this technique with an emphasis on issues related to experimental design and data analysis. ChIP-seq experiments generate large quantities of data, and effective computational analysis will be crucial for uncovering biological mechanisms.

  16. ChIPBase v2.0: decoding transcriptional regulatory networks of non-coding RNAs and protein-coding genes from ChIP-seq data.

    PubMed

    Zhou, Ke-Ren; Liu, Shun; Sun, Wen-Ju; Zheng, Ling-Ling; Zhou, Hui; Yang, Jian-Hua; Qu, Liang-Hu

    2017-01-04

    The abnormal transcriptional regulation of non-coding RNAs (ncRNAs) and protein-coding genes (PCGs) is contributed to various biological processes and linked with human diseases, but the underlying mechanisms remain elusive. In this study, we developed ChIPBase v2.0 (http://rna.sysu.edu.cn/chipbase/) to explore the transcriptional regulatory networks of ncRNAs and PCGs. ChIPBase v2.0 has been expanded with ∼10 200 curated ChIP-seq datasets, which represent about 20 times expansion when comparing to the previous released version. We identified thousands of binding motif matrices and their binding sites from ChIP-seq data of DNA-binding proteins and predicted millions of transcriptional regulatory relationships between transcription factors (TFs) and genes. We constructed 'Regulator' module to predict hundreds of TFs and histone modifications that were involved in or affected transcription of ncRNAs and PCGs. Moreover, we built a web-based tool, Co-Expression, to explore the co-expression patterns between DNA-binding proteins and various types of genes by integrating the gene expression profiles of ∼10 000 tumor samples and ∼9100 normal tissues and cell lines. ChIPBase also provides a ChIP-Function tool and a genome browser to predict functions of diverse genes and visualize various ChIP-seq data. This study will greatly expand our understanding of the transcriptional regulations of ncRNAs and PCGs. © The Author(s) 2016. Published by Oxford University Press on behalf of Nucleic Acids Research.

  17. Photosynthates as dominant source of CH4 and CO2 in soil water and CH4 emitted to the atmosphere from paddy fields

    NASA Astrophysics Data System (ADS)

    Minoda, Tomomi; Kimura, Mamoto; Wada, Eitaro

    1996-09-01

    Emission rates of CH4 from paddy soil with and without rice straw applications were measured with pot experiments to estimate the contribution of rice straw to the total CH4 emission during the growth period of rice plants. The CH4 derived from rice straw was calculated to be 44% of the total emission. 13CO2 uptake experiments were also carried out four times from June 30 to September 13, 1994, to estimate the contribution of photosynthesized carbon to CH4 emission. The contribution percentages of photosynthesized carbon to the total CH4 emitted to the atmosphere were 3.8% around June 30, 31% around July 25, 30% around August 19, and 14% around September 13 in the treatment with rice straw applications, and 52% around July 25, 28% around August 19, and 15% around September 13 in the treatment without rice straw applications. They were calculated to be 22% and 29% for the entire growth period in the treatments with and without rice straw applications, respectively. The contribution percentages of photosynthesized carbon to the total CH4 and inorganic carbon (Σ CO2) dissolved in soil water were 1.3%, 30%, 29%, and 34% for dissolved CH4 and 3.0%, 36%, 30% and 28% for dissolved inorganic carbon around June 30, July 25, August l9, and September 13, respectively, in the treatment with rice straw applications. They were 70%, 23%, and 32% for dissolved CH4 and 31%, 16%, and 19% for dissolved inorganic carbon around July 25, August 19, and September 13, respectively, in the treatment without rice straw applications.

  18. Contribution of Anthropogenic and Natural Emissions to Global CH4 Balances by Utilizing δ13C-CH4 Observations in CarbonTracker Data Assimilation System (CTDAS)

    NASA Astrophysics Data System (ADS)

    Kangasaho, V. E.; Tsuruta, A.; Aalto, T.; Backman, L. B.; Houweling, S.; Krol, M. C.; Peters, W.; van der Laan-Luijkx, I. T.; Lienert, S.; Joos, F.; Dlugokencky, E. J.; Michael, S.; White, J. W. C.

    2017-12-01

    The atmospheric burden of CH4 has more than doubled since preindustrial time. Evaluating the contribution from anthropogenic and natural emissions to the global methane budget is of great importance to better understand the significance of different sources at the global scale, and their contribution to changes in growth rate of atmospheric CH4 before and after 2006. In addition, observations of δ13C-CH4 suggest an increase in natural sources after 2006, which matches the observed increase and variation of CH4 abudance. Methane emission sources can be identified using δ13C-CH4, because different sources produce methane with process-specific isotopic signatures. This study focuses on inversion model based estimates of global anthropogenic and natural methane emission rates to evaluate the existing methane emission estimates with a new δ13C-CH4 inversion system. In situ measurements of atmospheric methane and δ13C-CH4 isotopic signature, provided by the NOAA Global Monitoring Division and the Institute of Arctic and Alpine Research, will be assimilated into the CTDAS-13C-CH4. The system uses the TM5 atmospheric transport model as an observation operator, constrained by ECMWF ERA Interim meteorological fields, and off-line TM5 chemistry fields to account for the atmospheric methane sink. LPX-Bern DYPTOP ecosystem model is used for prior natural methane emissions from wetlands, peatlands and mineral soils, GFED v4 for prior fire emissions and EDGAR v4.2 FT2010 inventory for prior anthropogenic emissions. The EDGAR antropogenic emissions are re-divided into enteric fermentation and manure management, landfills and waste water, rice, coal, oil and gas, and residential emissions, and the trend of total emissions is scaled to match optimized anthropogenic emissions from CTE-CH4. In addition to these categories, emissions from termites and oceans are included. Process specific δ13C-CH4 isotopic signatures are assigned to each emission source to estimate 13CH4 fraction

  19. The Grammar of Ch'orti' Maya Folktales

    ERIC Educational Resources Information Center

    Dugan, James Timothy

    2014-01-01

    This study describes the grammar of the Ch'orti' Maya language as it appears in a collection of oral literature. I collected the stories that form the basis of this study in and around Jocotan, Guatemala, during 2004 and 2005. I worked with bilingual story-tellers to make audio recordings of the original Ch'orti'-language tales, produce textual…

  20. How Many Ch-Class NEOs Do We Expect?

    NASA Astrophysics Data System (ADS)

    Rivkin, A. S.; DeMeo, F. E.

    2017-09-01

    The Ch spectral class is thought to contain objects that have water in their minerals, and they are of great interest to scientists and the nascent asteroid mining industry. We use models of asteroid delivery to near-Earth space and measurements of the different compositions of asteroids to estimate there should be at least 20 Ch asteroids larger than 100 m that are more accessible than the Moon, though we note that there are some untested assumptions that lead to that number. Further work must be done to identify the specific Ch asteroids.

  1. Characterization of the Minimum Energy Paths for the Reactions of CH(X(sup 2 Pi) and (1)CH2 with C2H2

    NASA Technical Reports Server (NTRS)

    Walch, Stephen P.; Langhoff, S. R. (Technical Monitor)

    1994-01-01

    The reactions of CH(sup 2 Pi) and singlet methylene (1)CH2 with acetylene lead to intermediates which may be important in soot formation. CH(sup 2 Pi) + acetylene leads to CHCHCH (C3H3), CHCCH (C3H2), and propargyl (CH2CCH). (1)CH2 + acetylene leads to cyclopropene and propargyl. All of these reaction products are formed with no barrier. Miller and Melius have previously discussed the dimerization of propargyl to give benzene. C3H3 and C3H2 can dimerize with no barrier to give benzene and para-benzyne, respectively. C3H3 and C3H2 can also add to smaller polynuclear aromatic hydrocarbons (PAH), and may be important species in forming larger PAH or fullerenes.

  2. Microwave Spectroscopic Investigations of the C-H\\cdotsπ Containing Complexes CH_2F_2\\cdotsPROPYNE and CH_2ClF\\cdotsPROPYNE

    NASA Astrophysics Data System (ADS)

    Peebles, Rebecca A.; Peebles, Sean A.; Christenholz, Cori L.; Ernst, Anthony A.; Dhahir, Yasser J.

    2013-06-01

    The spectra of the CH_2F_2\\cdotspropyne and CH_2ClF\\cdotspropyne complexes have been studied by chirped-pulse and resonant cavity Fourier-transform microwave spectroscopy and by ab initio calculations at the MP2/6-311++G(2d,2p) level. Both complexes contain C-H\\cdotsπ contacts, with the halogen atoms angled towards the methyl group end of the propyne. While CH_2F_2\\cdotspropyne has C_s symmetry, CH_2ClF\\cdotspropyne has C_1 symmetry, with the fluorine and chlorine atoms straddling the propyne. Investigation of four single ^{13}C and the DC≡CCH_3 isotopologues in CH_2F_2\\cdotspropyne has allowed a detailed structural determination, while only the ^{35}Cl and ^{37}Cl isotopologues have so far been assigned for CH_2ClF\\cdotspropyne. Experimental data will be compared with ab initio results and with the analogous acetylene complexes, both of which have C_s symmetry structures, with double C-H\\cdotsπ interactions.

  3. Height velocity and IGF-I assessment in the diagnosis of childhood onset GH insufficiency: do we still need a second GH stimulation test?

    PubMed

    Cianfarani, Stefano; Tondinelli, Tiziana; Spadoni, Gian Luigi; Scirè, Giuseppe; Boemi, Sergio; Boscherini, Brunetto

    2002-08-01

    The diagnosis of GH insufficiency (GHI) in childhood is not straightforward. Our aim was to test the sensitivity and specificity of height velocity (HV), IGF-I, IGFBP-3 and GH stimulation tests alone or in combination in the diagnosis of GHI. A retrospective review of patients with GHI and idiopathic short stature (ISS) diagnosed in our centre and followed up to the completion of linear growth. Thirty-three GHI children and 56 children with ISS were evaluated. GHI diagnosis was based on fulfilment of anthropometric, endocrine and neuroradiological criteria: stature < or = -2 z-score, delayed bone age (at least 1 year), GH peak response to at least two different provocative tests < 10 micro g/l (20 mU/l), brain MRI positive for hypothalamus-pituitary abnormalities, catch-up growth during the first year of GH replacement therapy > or = 75th centile, peak GH response to a third provocative test after growth completion < 10 micro g/l (20 mU/l). Children with anthropometry resembling that of GHI but with peak GH responses > 10 micro g/l (20 mU/l) were diagnosed as ISS. All subjects underwent standard anthropometry. GH secretory status was assessed by clonidine, arginine and GHRH plus arginine stimulation tests. IGF-I and IGFBP-3 circulating levels were measured by immunoradiometric assay (IRMA). The following cut-off values were chosen to discriminate between GHI and nonGHI short children: HV < 25th centile over the 6-12 months prior to the initiation of GH therapy, peak GH responses < 10 or < 7 micro g/l (< 20 or < 14 mU/l) and IGF-I and IGFBP-3-values < -1.9 z-score. Sensitivity (true positive ratio) and specificity (true negative ratio) were evaluated. Taking 10 micro g/l (20 mU/l) as the cut-off value, sensitivity was 100% and specificity 57% for GH provocative tests, whereas taking 7 as the cut-off value, sensitivity was 66% and specificity rose to 78%. Sensitivity was 73% for IGF-I and 30% for IGFBP-3 measurement, whilst specificity was 95% for IGF-I and 98% for

  4. (Phosphinoalkyl)silanes. 4.(1) Hydrozirconation as a Non-Photochemical Route to (Phosphinopropyl)silanes: Facile Assembly of the Bis(3-(diphenylphosphino)propyl)silyl ("biPSi") Ligand Framework. Access to the Related Poly(3-(dimethylsilyl)propyl)phosphines R(n)()P(CH(2)CH(2)CH(2)SiMe(2)H)(3)(-)(n)() (n = 1, R = Ph; n = 0).

    PubMed

    Zhou, Xiaobing; Stobart, Stephen R.; Gossage, Robert A.

    1997-08-13

    Treatment of SiEt(3)(CH=CH(2)) with ZrCp(2)HCl (Schwartz's reagent) followed by reaction with PPh(2)Cl provides a high-yield (75%) route to Ph(2)PCH(2)CH(2)SiEt(3), and accordingly hydrozirconation of CH(2)=CHCH(2)SiHMe(2) affords the intermediate ZrCp(2)(CH(2)CH(2)CH(2)SiHMe(2))Cl (2). The latter, which is very sensitive to hydrolysis and reacts with HCl forming SiHMe(2)Pr(n)() and with NBS or I(2) affording SiHMe(2)CH(2)CH(2)CH(2)X (X = Br (3), I (4)), behaves similarly with PPh(2)Cl, PPhCl(2), or PBr(3) undergoing cleavage to the known Ph(2)PCH(2)CH(2)CH(2)SiMe(2)H (i.e. chelH, A) and the novel bis- and tris(silylpropyl)phosphines PhP(CH(2)CH(2)CH(2)SiMe(2)H)(2) (5) and P(CH(2)CH(2)CH(2)SiMe(2)H)(3) (6), respectively, with concomitant formation of ZrCp(2)Cl(2). Corresponding hydroboration of allylsilanes is facile, but subsequent phosphine halide cleavage yields (phosphinoalkyl)silanes only as constituents of intractable mixtures. Hydrozirconation followed by phosphination with PPh(2)Cl also converts SiHMe(CH(2)CH=CH(2))(2) to SiHMe(CH(2)CH(2)CH(2)PPh(2))(2) (i.e. biPSiH, B) together with a propyl analogue Ph(2)PCH(2)CH(2)CH(2)SiMe(Pr(n)())H (7) of A (ca. 2:1 ratio), as well as SiH(CH(2)CH=CH(2))(3) to a mixture (ca. 5:2:1 ratio) of SiH(CH(2)CH(2)CH(2)PPh(2))(3) (i.e. triPSiH, C), a new analogue SiH(Pr(n)())(CH(2)CH(2)CH(2)PPh(2))(2) (8) of B, and a further analogue Ph(2)PCH(2)CH(2)CH(2)SiHPr(n)()(2) (9) of A. A further analogue SiH(2)(CH(2)CH(2)CH(2)PPh(2))(2) (10) of biPSiH (B) is obtained similarly starting from SiH(2)(CH(2)CH=CH(2))(2). Steric control of silylalkyl cleavage from 2 is indicated by the fact that, like PPh(2)Cl (which forms B), two further biPSiH analogues SiH(Me)[CH(2)CH(2)CH(2)P(n-hex)(2)](2) (11) and SiH(Me)(CH(2)CH(2)CH(2)PPhBz)(2) (12) were obtained using P(n-hex)(2)Cl (i.e. n-hex = CH(3)(CH(2))(4)CH(2)-) or PPhBzCl (i.e. Bz = -CH(2)C(6)H(5)), respectively, whereas neither PPr(i)(2)Cl nor PBu(t)(2)Cl led to (phosphinoalkyl)silane formation

  5. 40 CFR 1065.660 - THC, NMHC, and CH4 determination.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 33 2014-07-01 2014-07-01 false THC, NMHC, and CH4 determination. 1065... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.660 THC, NMHC, and CH4 determination. (a) THC determination and initial THC/CH 4 contamination corrections. (1) If we...

  6. 40 CFR 1065.660 - THC, NMHC, and CH4 determination.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 34 2012-07-01 2012-07-01 false THC, NMHC, and CH4 determination. 1065... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.660 THC, NMHC, and CH4 determination. (a) THC determination and initial THC/CH 4 contamination corrections. (1) If we...

  7. 40 CFR 1065.660 - THC, NMHC, and CH4 determination.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 34 2013-07-01 2013-07-01 false THC, NMHC, and CH4 determination. 1065... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.660 THC, NMHC, and CH4 determination. (a) THC determination and initial THC/CH 4 contamination corrections. (1) If we...

  8. 40 CFR 1065.660 - THC, NMHC, and CH4 determination.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 33 2011-07-01 2011-07-01 false THC, NMHC, and CH4 determination. 1065... POLLUTION CONTROLS ENGINE-TESTING PROCEDURES Calculations and Data Requirements § 1065.660 THC, NMHC, and CH4 determination. (a) THC determination and THC/CH 4 initial contamination corrections. (1) If we...

  9. Gas-Phase Synthesis and Characterization of CH4-Loaded Hydroquinone Clathrates

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

    Lee, J.; Lee, Y; Takeya, S

    2010-01-01

    A CH{sub 4}-loaded hydroquinone (HQ) clathrate was synthesized via a gas-phase reaction using the {alpha}-form of crystalline HQ and CH{sub 4} gas at 12 MPa and room temperature. Solid-state {sup 13}C cross-polarization/magic angle spinning (CP/MAS) NMR and Raman spectroscopic measurements confirm the incorporation of CH{sub 4} molecules into the cages of the HQ clathrate framework. The chemical analysis indicates that about 69% of the cages are filled by CH{sub 4} molecules, that is, 0.69 CH{sub 4} per three HQ molecules. Rietveld refinement using synchrotron X-ray powder diffraction (XRD) data shows that the CH{sub 4}-loaded HQ clathrate adopts the {beta}-form ofmore » HQ clathrate in a hexagonal space group R3 with lattice parameters of a = 16.6191 {angstrom} and c = 5.5038 {angstrom}. Time-resolved synchrotron XRD and quadrupole mass spectroscopic measurements show that the CH{sub 4}-loaded HQ clathrate is stable up to 368 K and gradually transforms to the {alpha}-form by releasing the confined CH{sub 4} gases between 368-378 K. Using solid-state {sup 13}C CP/MAS NMR, the reaction kinetics between the {alpha}-form HQ and CH{sub 4} gas is qualitatively described in terms of the particle size of the crystalline HQ.« less

  10. Arctic tundra and mountain landscapes are persistent sinks of atmospheric CH4

    NASA Astrophysics Data System (ADS)

    Christiansen, Jesper; Winkler, Renato; Juncher Jørgensen, Christian

    2017-04-01

    Recent studies have shown significant rates of net uptake of atmospheric methane (CH4) in Arctic tundra soils. Oxidation of CH4 in these cold, dry soils in the Arctic region can counteract CH4 emissions from wetlands and play a potential important role for the net Arctic CH4 budget. However, significant knowledge gaps exist on the overall magnitude of the net CH4 sink in these cold, dry systems as the spatial and environmental limits for CH4 oxidation has not been determined. In particular, the extent, magnitude and drivers of CH4 oxidation in mountains and alpine landforms, which occupy large land areas in the Arctic and High Arctic has not yet been investigated leaving a potential vast CH4 sink unquantified with major potential implications for our conceptual view of Arctic CH4 budget in a changing climate. Here we present the results from two expeditions in the summers of 2015 and 2016 from Disko Bay and in the pro-glacial landscape in vicinity of the Russell Glacier, Kangerlussuaq, Greenland, respectively. The aim of our work is to determine the magnitude and extent of net uptake of atmospheric CH4 across a variety of previously unexplored dry tundra and post-glacial landforms in the Arctic, i.e. marginal moraines and other glacial features at the Greenland ice sheet as well as mountain tops and outwash plains. We used high-precision, mobile cavity-ring-down spectrometers (e.g. model G4301 GasScouter, Picarro Inc.) to achieve reliable flux estimates in sub-ambient CH4 concentration levels with a 4-minute enclosure time per chamber measurement. Our results show a persistent net uptake of CH4 uptake in these dry, extreme environments that rival the sink strength observed in temperate forest soils, otherwise considered the primary global terrestrial sink of atmospheric CH4. In this dynamic glacial landscape the magnitude of the net CH4 uptake is mainly constrained by recent landscape evolution along glacier margins and meltwater systems. Utilizing the high

  11. Coupled-cluster sum-frequency generation nonlinear susceptibilities of methyl (CH3) and methylene (CH2) groups.

    PubMed

    Tetsassi Feugmo, Conrard Giresse; Liégeois, Vincent; Champagne, Benoît

    2017-11-15

    The first vibrational sum frequency generation (SFG) spectra based on molecular properties calculated at the coupled cluster singles and doubles (CCSD) level of approximation have been simulated for interfacial model alkyl chains, providing benchmark data for comparisons with approximate methods, including density functional theory (DFT). The approach proceeds in three steps. In the first two steps, the molecular spectral properties are determined: the vibrational normal modes and frequencies and then the derivatives of the dipole moment and of the polarizability with respect to the normal coordinates. These derivatives are evaluated with a numerical differentiation approach, of which the accuracy was monitored using Romberg's procedure. Then, in the last step, a three-layer model is employed to evaluate the macroscopic second-order nonlinear optical responses and thereby the simulated SFG spectra of the alkyl interface. Results emphasize the following facts: (i) the dipole and polarizability derivatives calculated at the DFT level with the B3LYP exchange-correlation functional can differ, with respect to CCSD, by as much as ±10 to 20% and ±20 to 50% for the CH 3 and CH 2 vibrations, respectively; (ii) these differences are enhanced when considering the SFG intensities as well as their variations as a function of the experimental configuration (ppp versus ssp) and as a function of the tilt and rotation angles, defining the orientation of the alkyl chain at the interface; (iii) these differences originate from both the vibrational normal coordinates and the Cartesian derivatives of the dipole moment and polarizability; (iv) freezing the successive fragments of the alkyl chain strongly modifies the SFG spectrum and enables highlighting the delocalization effects between the terminal CH 3 group and its neighboring CH 2 units; and finally (v) going from the free chain to the free methyl model, and further to C 3v constraints on leads to large variations of two ratios

  12. Photochemical Modeling of CH3 Abundances in the Outer Solar System

    NASA Technical Reports Server (NTRS)

    Lee, Anthony Y. T.; Yung, Yuk L.; Moses, Julianne

    2000-01-01

    Recent measurements of methyl radicals (CH3) in the upper atmospheres of Saturn and Neptune by the Infrared Space Observatory (ISO) provide new constraints to photochemical models of hydrocarbon chemistry in the outer solar system. The derived column abundances of CH3 on Saturn above 10 mbar and Neptune above the 0.2 mbar pressure level are (2.5 - 6.0) x 10(exp 13) / sq cm and (0.7 - 2.8) x 10(exp 13) / sq cm, respectively. We use the updated Caltech/Jet Propulsion Laboratory photochemical model, which incorporates hydrocarbon photochemistry, vertical molecular and bulk atmospheric eddy diffusion, and realistic radiative transfer modeling, to study the CH3 abundances in the upper atmosphere of the giant planets and Titan. We identify the key reactions that control the concentrations of CH3 in the model, such as the three-body recombination reaction, CH3 + CH3 + M yields C2H6 + M. We evaluate and extrapolate the three-body rate constant of this reaction to the low-temperature limit (1.8 x 10(exp -16) T(sup -3.75) e(sup -300/T), T < 300 K) and compare methyl radical abundances in five atmospheres: Jupiter, Saturn, Uranus, Neptune, and Titan. The sensitivity of our models to the rate coefficients for the reactions H + CH3 + M yields CH4 + M, H + C2H3 yields C2H2 + H2, (sup 1)CH2 + H2 yields CH3 + H, and H + C2H5 yields 2CH3, the branching ratios of CH4 photolysis, vertical mixing in the five atmospheres, and Lyman alpha photon enhancement at the orbit of Neptune have all been tested. The results of our model CH3 abundances for both Saturn (5.1 x 10(exp 13) / sq cm) and Neptune (2.2 x 10(exp 13) / sq cm) show good agreement with ISO Short Wavelength Spectrometer measurements. Using the same chemical reaction set, our calculations also successfully generate vertical profiles of stable hydrocarbons consistent with Voyager and ground-based measurements in these outer solar system atmospheres. Predictions of CH3 column concentrations (for p <= 0.2 mbar) in the atmospheres

  13. Megafauna and frozen soil: the drivers of atmospheric CH4 dynamics

    NASA Astrophysics Data System (ADS)

    Zimov, N.; Zimov, S. A.

    2010-12-01

    During the last deglaciation (LD) a strong increase in atmospheric methane (CH4) concentrations occurred simultaneously with a rise in Greenland temperatures indicating that in the north, during this time period, strong CH4 sources “awakened”, as additionally documented by the appearance of a strong gradient between northern (Greenland) and southern (Antarctica) hemisphere atmospheric CH4 concentrations. This rise could not be caused by wetland expansion. A reconstruction of peatland formation dynamics has indicated that wetlands on Earth were few in LD and only actively expanded 10,000 yr BP, after atmospheric CH4 concentrations began to decline. Destabilization of methane clathrates also could not be the source for atmospheric CH4 increase. Geological CH4 (including methane clathrates) has the highest deuterium content (δD) among all of the known sources of CH4 while atmospheric CH4 δD values determined for the LD were record low. To explain recorded atmospheric CH4 and its isotopic dynamics required a strong northern source, which was active only during the LD and that provided very low δD CH4 values. Such a source is permafrost thawing under anaerobic conditions (or better stated soils of mammoth steppe-tundra ecosystems). Permafrost thawing is the strongest, among known, wetland sources (usually over 100g CH4/m2yr) and has a unique isotopic signature (δD = -400 per mil (-338 to -479 per mil), δ13C = -73 per mil (-58 to -99 per mil)). The main sources of atmospheric CH4 have different isotopic signatures (δ13C, δD). The isotopic content of atmospheric CH4 is a simple function of the weight average for all of the sources. Inclusion of permafrost source into a budget model of the atmospheric methane and its isotopes allowed us to reconstruct the dynamics of methane’s main sources. Model indicated geological source to be negligible as in LGM so and in LD and Holocene. During the glaciation, the largest methane source was megafauna, whose 1

  14. Supply- and Demand-Side Factors Influencing Utilization of Infant and Young Child Feeding Counselling Services in Viet Nam.

    PubMed

    Nguyen, Phuong H; Kim, Sunny S; Nguyen, Tuan T; Tran, Lan M; Hajeebhoy, Nemat; Frongillo, Edward A; Ruel, Marie T; Rawat, Rahul; Menon, Purnima

    2016-01-01

    Adequate utilization of services is critical to maximize the impact of counselling on infant and young child feeding (IYCF), but little is known about factors affecting utilization. Our study examined supply- and demand-side factors associated with the utilization of IYCF counselling services in Viet Nam. We used survey data from mothers with children <2y (n = 1,008) and health staff (n = 60) from the evaluation of a program that embedded IYCF counseling into the existing government health system. The frequency of never users, one-time users, repeat users, and achievers of the recommended minimum number of visits at health facilities were 45.1%, 13.0%, 28.4% and 13.5%, respectively. Poisson regression showed that demand-generation strategies, especially invitation cards, were the key factors determining one-time use (Prevalence ratio, PR 3.0, 95% CI: 2.2-4.2), repeated use (PR 3.2, 95% CI: 2.4-4.2), and achievement of minimum visits (PR 5.5, 95% CI: 3.6-8.4). Higher maternal education was associated with higher utilization both for one-time and repeated use. Being a farmer, belonging to an ethnic minority, and having a wasted child were associated with greater likelihood of achieving the minimum recommended number of visits, whereas child stunting or illness were not. Distance to health center was a barrier to repeated visits. Among supply-side factors, good counselling skills (PR: 1.3-1.8) was the most important factor associated with any service use, whereas longer employment duration and greater work pressure of health center staff were associated with lower utilization. Population attributable risk estimations showed that an additional 25% of the population would have achieved the minimum number of visits if exposed to three demand-generation strategies, and further increased to 49% if the health staff had good counseling skills and low work pressure. Our study provides evidence that demand-generation strategies are essential to increase utilization of facility

  15. Supply- and Demand-Side Factors Influencing Utilization of Infant and Young Child Feeding Counselling Services in Viet Nam

    PubMed Central

    Nguyen, Phuong H.; Kim, Sunny S.; Nguyen, Tuan T.; Tran, Lan M.; Hajeebhoy, Nemat; Frongillo, Edward A.; Ruel, Marie T.; Rawat, Rahul; Menon, Purnima

    2016-01-01

    Adequate utilization of services is critical to maximize the impact of counselling on infant and young child feeding (IYCF), but little is known about factors affecting utilization. Our study examined supply- and demand-side factors associated with the utilization of IYCF counselling services in Viet Nam. We used survey data from mothers with children <2y (n = 1,008) and health staff (n = 60) from the evaluation of a program that embedded IYCF counseling into the existing government health system. The frequency of never users, one-time users, repeat users, and achievers of the recommended minimum number of visits at health facilities were 45.1%, 13.0%, 28.4% and 13.5%, respectively. Poisson regression showed that demand-generation strategies, especially invitation cards, were the key factors determining one-time use (Prevalence ratio, PR 3.0, 95% CI: 2.2–4.2), repeated use (PR 3.2, 95% CI: 2.4–4.2), and achievement of minimum visits (PR 5.5, 95% CI: 3.6–8.4). Higher maternal education was associated with higher utilization both for one-time and repeated use. Being a farmer, belonging to an ethnic minority, and having a wasted child were associated with greater likelihood of achieving the minimum recommended number of visits, whereas child stunting or illness were not. Distance to health center was a barrier to repeated visits. Among supply-side factors, good counselling skills (PR: 1.3–1.8) was the most important factor associated with any service use, whereas longer employment duration and greater work pressure of health center staff were associated with lower utilization. Population attributable risk estimations showed that an additional 25% of the population would have achieved the minimum number of visits if exposed to three demand-generation strategies, and further increased to 49% if the health staff had good counseling skills and low work pressure. Our study provides evidence that demand-generation strategies are essential to increase utilization of

  16. Spectroscopic properties of morin in various CH3OH-H2O and CH3CN-H2O mixed solvents.

    PubMed

    Park, Hyoung-Ryun; Im, Seo-Eun; Seo, Jung-Ja; Kim, Bong-Gon; Yoon, Jin Ah; Bark, Ki-Min

    2015-01-01

    The specific fluorescence properties of morin (3,2',4',5,7-pentahydroxyflavone) were studied in various CH3OH-H2O and CH3CN-H2O mixed solvents. Although the dihedral angle is large in the S0 state, morin has an almost planar molecular structure in the S1 state owing to the very low rotational energy barrier around the interring bond between B and the A, C ring. The excited state intramolecular proton transfer (ESIPT) at the S1 state cannot occur immediately after excitation, S1 → S0 fluorescence can be observed. Two conformers, Morin A and B have been known. At the CH3OH-H2O, Morin B will be the principal species but at the CH3CN-H2O, Morin A is the principal species. At the CH3OH-H2O, owing to the large Franck-Condon (FC) factor for S2 → S1 internal convernal (IC) and flexible molecular structure, only S1 → S0 fluorescence was exhibited. At the CH3CN-H2O, as the FC factor for S2 → S1 IC is small and molecular structure is rigid, S2 → S0 and S1 → S0 dual fluorescence was observed. This abnormal fluorescence property was further supported by the small pK1 value, effective delocalization of the lone pair electrons of C(2')-OH to the A, C ring, and a theoretical calculation. © 2014 The American Society of Photobiology.

  17. Hot filament-dissociation of (CH3)3SiH and (CH3)4Si, probed by vacuum ultra violet laser time of flight mass spectroscopy.

    PubMed

    Sharma, Ramesh C; Koshi, Mitsuo

    2006-11-01

    The decomposition of trimethylsilane and tetramethylsilane has been investigated for the first time, using hot wire (catalytic) at various temperatures. Trimethylsilane is catalytic-dissociated in these species SiH(2), CH(3)SiH, CH(3), CH(2)Si. Time of flight mass spectroscopy signal of these species are linearly increasing with increasing catalytic-temperature. Time of flight mass spectroscopy (TOFMS) signals of (CH(3))(3)SiH and photodissociated into (CH(3))(2)SiH are decreasing with increasing hot filament temperature. TOFMS signal of (CH(3))(4)Si is decreasing with increasing hot wire temperature, but (CH(3))(3)Si signal is almost constant with increasing the temperature. We calculated activation energies of dissociated species of the parental molecules for fundamental information of reaction kinetics for the first time. Catalytic-dissociation of trimethylsilane, and tetramethylsilane single source time of flight coupled single photon VUV (118 nm) photoionization collisionless radicals at temperature range of tungsten filament 800-2360 K. The study is focused to understand the fundamental information on reaction kinetics of these molecules at hot wire temperature, and processes of catalytic-chemical vapour deposition (Cat-CVD) technique which could be implemented in amorphous and crystalline SiC semiconductors thin films.

  18. Le Châtelier reciprocal relations and the mechanical analog

    NASA Astrophysics Data System (ADS)

    Gilmore, Robert

    1983-08-01

    Le Châtelier's principle is discussed carefully in terms of two sets of simple thermodynamic examples. The principle is then formulated quantitatively for general thermodynamic systems. The formulation is in terms of a perturbation-response matrix, the Le Châtelier matrix [L]. Le Châtelier's principle is contained in the diagonal elements of this matrix, all of which exceed one. These matrix elements describe the response of a system to a perturbation of either its extensive or intensive variables. These response ratios are inverses of each other. The Le Châtelier matrix is symmetric, so that a new set of thermodynamic reciprocal relations is derived. This quantitative formulation is illustrated by a single simple example which includes the original examples and shows the reciprocities among them. The assumptions underlying this new quantitative formulation of Le Châtelier's principle are general and applicable to a wide variety of nonthermodynamic systems. Le Châtelier's principle is formulated quantitatively for mechanical systems in static equilibrium, and mechanical examples of this formulation are given.

  19. A brief overview of the Chemistry-Aerosol Mediterranean Experiment (ChArMEx) database and campaign operation centre (ChOC)

    NASA Astrophysics Data System (ADS)

    Ferré, Hélène; Dulac, François; Belmahfoud, Nizar; Brissebrat, Guillaume; Cloché, Sophie; Descloitres, Jacques; Fleury, Laurence; Focsa, Loredana; Henriot, Nicolas; Ramage, Karim; Vermeulen, Anne

    2016-04-01

    Initiated in 2010 in the framework of the multidisciplinary research programme MISTRALS (Mediterranean Integrated Studies at Regional and Local Scales; http:www.mistrals-home.org), the Chemistry-Aerosol Mediterranean Experiment (ChArMEx, http://charmex.lsce.ipsl.fr/) aims at federating the scientific community for an updated assessment of the present and future state of the atmospheric environment in the Mediterranean Basin, and of its impacts on the regional climate, air quality, and marine biogeochemistry. The project combines mid- and long-term monitoring, intensive field campaigns, use of satellite data, and modelling studies. In this presentation we provide an overview of the campaign operation centre (http://choc.sedoo.fr/) and project database (http://mistrals.sedoo.fr/ChArMEx), at the end of the first experimental phase of the project that included a series of large campaigns based on airborne means (including balloons and various aircraft) and a network of surface stations. Those campaigns were performed mainly in the western Mediterranean basin in the summer of 2012, 2013 and 2014 with the help of the ChArMEx Operation Centre (ChOC), an open web site that has the objective to gather and display daily quick-looks from model forecasts and near-real time in situ and remote sensing observations of physical and chemical weather conditions relevant for the everyday campaign operation decisions. The ChOC is also useful for post campaign analyses and can be completed with a number of quick-looks of campaign results obtained later in order to offer an easy access to, and comprehensive view of all available data during the campaign period. The items included are selected according to the objectives and location of the given campaigns. The second experimental phase of ChArMEx from 2015 on is more focused on the eastern basin. In addition, the project operation centre is planned to be adapted for a joint MERMEX-ChArMEx oceanographic cruise (PEACETIME) for a study at

  20. Ozone Depletion Potential of CH3Br

    NASA Technical Reports Server (NTRS)

    Sander, Stanley P.; Ko, Malcolm K. W.; Sze, Nien Dak; Scott, Courtney; Rodriquez, Jose M.; Weisenstein, Debra K.

    1998-01-01

    The ozone depletion potential (ODP) of methyl bromide (CH3Br) can be determined by combining the model-calculated bromine efficiency factor (BEF) for CH3Br and its atmospheric lifetime. This paper examines how changes in several key kinetic data affect BEF. The key reactions highlighted in this study include the reaction of BrO + H02, the absorption cross section of HOBr, the absorption cross section and the photolysis products of BrON02, and the heterogeneous conversion of BrON02 to HOBR and HN03 on aerosol particles. By combining the calculated BEF with the latest estimate of 0.7 year for the atmospheric lifetime of CH3Br, the likely value of ODP for CH3Br is 0.39. The model-calculated concentration of HBr (approximately 0.3 pptv) in the lower stratosphere is substantially smaller than the reported measured value of about I pptv. Recent publications suggested models can reproduce the measured value if one assumes a yield for HBr from the reaction of BrO + OH or from the reaction of BrO + H02. Although the DeAlore et al. evaluation concluded any substantial yield of HBr from BrO + HO2 is unlikely, for completeness, we calculate the effects of these assumed yields on BEF for CH3Br. Our calculations show that the effects are minimal: practically no impact for an assumed 1.3% yield of HBr from BrO + OH and 10% smaller for an assumed 0.6% yield from BrO + H02.

  1. Two-Photon Holographic Stimulation of ReaChR

    PubMed Central

    Chaigneau, Emmanuelle; Ronzitti, Emiliano; Gajowa, Marta A.; Soler-Llavina, Gilberto J.; Tanese, Dimitrii; Brureau, Anthony Y. B.; Papagiakoumou, Eirini; Zeng, Hongkui; Emiliani, Valentina

    2016-01-01

    Optogenetics provides a unique approach to remotely manipulate brain activity with light. Reaching the degree of spatiotemporal control necessary to dissect the role of individual cells in neuronal networks, some of which reside deep in the brain, requires joint progress in opsin engineering and light sculpting methods. Here we investigate for the first time two-photon stimulation of the red-shifted opsin ReaChR. We use two-photon (2P) holographic illumination to control the activation of individually chosen neurons expressing ReaChR in acute brain slices. We demonstrated reliable action potential generation in ReaChR-expressing neurons and studied holographic 2P-evoked spiking performances depending on illumination power and pulse width using an amplified laser and a standard femtosecond Ti:Sapphire oscillator laser. These findings provide detailed knowledge of ReaChR's behavior under 2P illumination paving the way for achieving in depth remote control of multiple cells with high spatiotemporal resolution deep within scattering tissue. PMID:27803649

  2. Mobilization of Selenite by Ralstonia metallidurans CH34

    PubMed Central

    Roux, Murielle; Sarret, Géraldine; Pignot-Paintrand, Isabelle; Fontecave, Marc; Coves, Jacques

    2001-01-01

    Ralstonia metallidurans CH34 (formerly Alcaligenes eutrophus CH34) is a soil bacterium characteristic of metal-contaminated biotopes, as it is able to grow in the presence of a variety of heavy metals. R. metallidurans CH34 is reported now to resist up to 6 mM selenite and to reduce selenite to elemental red selenium as shown by extended X-ray absorption fine-structure analysis. Growth kinetics analysis suggests an adaptation of the cells to the selenite stress during the lag-phase period. Depending on the culture conditions, the medium can be completely depleted of selenite. Selenium accumulates essentially in the cytoplasm as judged from electron microscopy and energy-dispersive X-ray analysis. Elemental selenium, highly insoluble, represents a nontoxic storage form for the bacterium. The ability of R. metallidurans CH34 to reduce large amounts of selenite may be of interest for bioremediation processes targeting selenite-polluted sites. PMID:11157242

  3. Data exploration, quality control and statistical analysis of ChIP-exo/nexus experiments

    PubMed Central

    Welch, Rene; Chung, Dongjun; Grass, Jeffrey; Landick, Robert

    2017-01-01

    Abstract ChIP-exo/nexus experiments rely on innovative modifications of the commonly used ChIP-seq protocol for high resolution mapping of transcription factor binding sites. Although many aspects of the ChIP-exo data analysis are similar to those of ChIP-seq, these high throughput experiments pose a number of unique quality control and analysis challenges. We develop a novel statistical quality control pipeline and accompanying R/Bioconductor package, ChIPexoQual, to enable exploration and analysis of ChIP-exo and related experiments. ChIPexoQual evaluates a number of key issues including strand imbalance, library complexity, and signal enrichment of data. Assessment of these features are facilitated through diagnostic plots and summary statistics computed over regions of the genome with varying levels of coverage. We evaluated our QC pipeline with both large collections of public ChIP-exo/nexus data and multiple, new ChIP-exo datasets from Escherichia coli. ChIPexoQual analysis of these datasets resulted in guidelines for using these QC metrics across a wide range of sequencing depths and provided further insights for modelling ChIP-exo data. PMID:28911122

  4. Kinetics of the Br2-CH3CHO Photochemical Chain Reaction

    NASA Technical Reports Server (NTRS)

    Nicovich, J. M.; Shackelford, C. J.; Wine, P. H.

    1997-01-01

    Time-resolved resonance fluorescence spectroscopy was employed in conjunction with laser flash photolysis of Br2 to study the kinetics of the two elementary steps in the photochemical chain reaction nBr2 + nCH3CHO + hv yields nCH3CBrO + nHBr. In the temperature range 255-400 K, the rate coefficient for the reaction Br((sup 2)P(sub 3/2)) + CH3CHO yields CH3CO + HBr is given by the Arrhenius expression k(sub 6)(T) = (1.51 +/- 0.20) x 10(exp -11) exp(-(364 +/- 41)/T)cu cm/(molecule.s). At 298 K, the reaction CH3CO + Br2 yields CH3CBrO + Br proceeds at a near gas kinetic rate, k(sub 7)(298 K) = (1.08 +/- 0.38) x 10(exp -10)cu cm/(molecule.s).

  5. Hyperfine excitation of CH in collisions with atomic and molecular hydrogen

    NASA Astrophysics Data System (ADS)

    Dagdigian, Paul J.

    2018-04-01

    We investigate here the excitation of methylidene (CH) induced by collisions with atomic and molecular hydrogen (H and H2). The hyperfine-resolved rate coefficients were obtained from close coupling nuclear-spin-free scattering calculations. The calculations are based upon recent, high-accuracy calculations of the CH(X2Π)-H(2S) and CH(X2Π)-H2 potential energy surfaces. Cross-sections and rate coefficients for collisions with atomic H, para-H2, and ortho-H2 were computed for all transitions between the 32 hyperfine levels for CH(X2Π) involving the n ≤ 4 rotational levels for temperatures between 10 and 300 K. These rate coefficients should significantly aid in the interpretation of astronomical observations of CH spectra. As a first application, the excitation of CH is simulated for conditions in typical molecular clouds.

  6. Communication: Photodissociation of CH3CHO at 308 nm: Observation of H-roaming, CH3-roaming, and transition state pathways together along the ground state surface

    NASA Astrophysics Data System (ADS)

    Li, Hou-Kuan; Tsai, Po-Yu; Hung, Kai-Chan; Kasai, Toshio; Lin, King-Chuen

    2015-01-01

    Following photodissociation of acetaldehyde (CH3CHO) at 308 nm, the CO(v = 1-4) fragment is acquired using time-resolved Fourier-transform infrared emission spectroscopy. The CO(v = 1) rotational distribution shows a bimodal feature; the low- and high-J components result from H-roaming around CH3CO core and CH3-roaming around CHO radical, respectively, in consistency with a recent assignment by Kable and co-workers (Lee et al., Chem. Sci. 5, 4633 (2014)). The H-roaming pathway disappears at the CO(v ≥ 2) states, because of insufficient available energy following bond-breaking of H + CH3CO. By analyzing the CH4 emission spectrum, we obtained a bimodal vibrational distribution; the low-energy component is ascribed to the transition state (TS) pathway, consistent with prediction by quasiclassical trajectory calculations, while the high-energy component results from H- and CH3-roamings. A branching fraction of H-roaming/CH3-roaming/TS contribution is evaluated to be (8% ± 3%)/(68% ± 10%)/(25% ± 5%), in which the TS pathway was observed for the first time. The three pathways proceed concomitantly along the electronic ground state surface.

  7. Radical routes to interstellar glycolaldehyde. The possibility of stereoselectivity in gas-phase polymerization reactions involving CH(2)O and ˙CH(2)OH.

    PubMed

    Wang, Tianfang; Bowie, John H

    2010-10-21

    A previous report that the interstellar molecule glycolaldehyde (HOCH(2)CHO) can be made from hydroxymethylene (HOCH:) and formaldehyde has been revisited at the CCSD(T)/6-311++G(3df,2p)//MP2/6-311++G(3df,2p) level of theory. This reaction competes with the formation of acetic acid and methylformate, molecules which have also been detected in interstellar clouds. Other possible modes of formation of glycolaldehyde by radical/radical reactions have been shown to be viable theoretically as follows: HO˙+˙CH2CHO -->HOCH2CHO [ΔG(Γ)(298K)=-303kJ mol⁻¹] HOCH2˙+˙CHO-->HOCH2CHO (-259kJ mol⁻¹). The species in these two processes are known interstellar molecules. Key radicals ˙CH(2)CHO and ˙CH(2)OH in these sequences have been shown to be stable for the microsecond duration of neutralization/reionization experiments in the dual collision cells of a VG ZAB 2HF mass spectrometer. The polymerization reaction HOCH(2)CH˙OH + nCH(2)O → HOCH(2)[CH(OH)](n)˙CHOH (n = 1 to 3) has been studied theoretically and shown to be energetically feasible, as is the cyclization reaction of HOCH(2)[(CH(2)OH)(4)]˙CHOH (in the presence of one molecule of water at the reacting centre) to form glucose. The probability of such a reaction sequence is small even if polymerization were to occur in interstellar ice containing a significant concentration of CH(2)O. The large number of stereoisomers produced by such a reaction sequence makes the formation of a particular sugar, again for example glucose, an inefficient synthesis. The possibility of stereoselectivity occurring during the polymerization was investigated for two diastereoisomers of HOCH(2)[(CHOH)](2)˙CHOH. No significant difference was found in the transition state energies for addition of CH(2)O to these two diastereoisomers, but a barrier difference of 12 kJ mol(-1) was found for the H transfer reactions ˙OCH(2)[(CHOH)](2)CH(2)OH → HOCH(2)[(CHOH)(2)˙CHOH of the two diastereoisomers.

  8. Energetics of the O-H bond and of intramolecular hydrogen bonding in HOC6H4C(O)Y (Y = H, CH3, CH2CH=CH2, C[triple bond]CH, CH2F, NH2, NHCH3, NO2, OH, OCH3, OCN, CN, F, Cl, SH, and SCH3) compounds.

    PubMed

    Bernardes, Carlos E S; Minas da Piedade, Manuel E

    2008-10-09

    The energetics of the phenolic O-H bond in a series of 2- and 4-HOC 6H 4C(O)Y (Y = H, CH3, CH 2CH=CH2, C[triple bond]CH, CH2F, NH2, NHCH 3, NO2, OH, OCH3, OCN, CN, F, Cl, SH, and SCH3) compounds and of the intramolecular O...H hydrogen bond in 2-HOC 6H 4C(O)Y, was investigated by using a combination of experimental and theoretical methods. The standard molar enthalpies of formation of 2-hydroxybenzaldehyde (2HBA), 4-hydroxybenzaldehyde (4HBA), 2'-hydroxyacetophenone (2HAP), 2-hydroxybenzamide (2HBM), and 4-hydroxybenzamide (4HBM), at 298.15 K, were determined by micro- or macrocombustion calorimetry. The corresponding enthalpies of vaporization or sublimation were also measured by Calvet drop-calorimetry and Knudsen effusion measurements. The combination of the obtained experimental data led to Delta f H m (o)(2HBA, g) = -238.3 +/- 2.5 kJ.mol (-1), DeltafHm(o)(4HBA, g) = -220.3 +/- 2.0 kJ.mol(-1), Delta f H m (o)(2HAP, g) = -291.8 +/- 2.1 kJ.mol(-1), DeltafHm(o)(2HBM, g) = -304.8 +/- 1.5 kJ.mol (-1), and DeltafHm(o) (4HBM, g) = -278.4 +/- 2.4 kJ.mol (-1). These values, were used to assess the predictions of the B3LYP/6-31G(d,p), B3LYP/6-311+G(d,p), B3LYP/aug-cc-pVDZ, B3P86/6-31G(d,p), B3P86/6-311+G(d,p), B3P86/aug-cc-pVDZ, and CBS-QB3 methods, for the enthalpies of a series of isodesmic gas phase reactions. In general, the CBS-QB3 method was able to reproduce the experimental enthalpies of reaction within their uncertainties. The B3LYP/6-311+G(d,p) method, with a slightly poorer accuracy than the CBS-QB3 approach, achieved the best performance of the tested DFT models. It was further used to analyze the trends of the intramolecular O...H hydrogen bond in 2-HOC 6H 4C(O)Y evaluated by the ortho-para method and to compare the energetics of the phenolic O-H bond in 2- and 4-HOC 6H 4C(O)Y compounds. It was concluded that the O-H bond "strength" is systematically larger for 2-hydroxybenzoyl than for the corresponding 4-hydroxybenzoyl isomers mainly due to the presence of

  9. RKR Franck-Condon factors for blue and ultraviolet transitions of some molecules of astrophysical interest and some comments on the interstellar abundance of CH, CH+ and SiH+.

    NASA Technical Reports Server (NTRS)

    Liszt, H. S.; Hayden Smith, W.

    1972-01-01

    RKR Franck-Condon factors for thirteen of the blue and ultraviolet transitions of AlF, AlO, BH, BD, CH, CD, CH(+), SiO and SiH(+) have been calculated. The interstellar abundances of CH, CH(+) and SiH(+) are discussed with regard to recent laboratory measurements, our Franck-Condon factors, and observations of the sun and the interstellar medium.

  10. Father's involvement and its effect on early breastfeeding practices in Viet Nam.

    PubMed

    Bich, Tran Huu; Hoa, Dinh Thi Phuong; Ha, Nguyen Thanh; Vui, Le Thi; Nghia, Dang Thi; Målqvist, Mats

    2016-10-01

    Fathers have an important but often neglected role in the promotion of healthy breastfeeding practices in developing countries. A community-based education intervention was designed to mobilize fathers' support for early breastfeeding. This study aimed to evaluate an education intervention targeting fathers to increase the proportion of early breastfeeding initiation and to reduce prelacteal feeding. Quasi-experimental study design was used to compare intervention and control areas located in two non-adjacent rural districts that shared similar demographic and health service characteristics in northern Viet Nam. Fathers and expectant fathers with pregnant wives from 7 to 30 weeks gestational age were recruited. Fathers in the intervention area received breastfeeding education materials, counselling services at a commune health centre and household visits. They were also invited to participate in a breastfeeding promotion social event. After intervention, early breastfeeding initiation rate was 81.2% in the intervention area and 39.6% in the control area (P < 0.001). Babies in the intervention area were more likely to be breastfed within the first hour after birth [odds ratio (OR) 7.64, 95% confidence interval (CI) 4.81-12.12] and not to receive any prelacteal feeding (OR 4.43, 95% CI 2.88-6.82) compared with those in the control area. Fathers may positively influence the breastfeeding practices of mothers, and as a resource for early childcare, they can be mobilized in programmes aimed at improving the early initiation of breastfeeding. © 2015 John Wiley & Sons Ltd.

  11. CH functionalization of heteroaromatic compounds by transition metal catalysis

    NASA Astrophysics Data System (ADS)

    Tanba, Shunsuke; Fujiwara, Taiki; Monguchi, Daiki; Mori, Atsunori

    2010-06-01

    Transition metal-catalyzed CH functioanlization of thiazoles and thiophenes are carried out. The reaction of thiophene with aryl halide in the presence of a palladium catalyst underwent the CC bond forming reaction at the CH bond of thiophene. By employing the reaction head-to-tail-type oligothiophene is synthesized in a stepwise manner. When several azoles are treated with secondary amines and amides in the presence of a copper catalyst, oxidative CH-NH coupling took place to form the carbon-nitrogen bond.

  12. Towards the new CH2018 climate scenarios for Switzerland

    NASA Astrophysics Data System (ADS)

    Fischer, Andreas; Schär, Christoph; Croci-Maspoli, Mischa; Knutti, Reto; Liniger, Mark; Strassmann, Kuno

    2017-04-01

    There is a growing demand for regional assessments of future climate change and its impacts on society and ecosystems to inform and facilitate appropriate adaptation strategies. The basis for such assessments are consistent and up-to-date climate change scenarios on the local to regional scale. In Switzerland, an important step has been accomplished by the release of the climate scenarios in 2011 ("CH2011"). Since then, new climate model simulations have become available and the scientific understanding has improved. It is hence desirable to update these national scenarios. The new CH2018 scenarios are developed in the framework of the recently founded National Center for Climate Services (NCCS), a network consisting of several federal offices and academic partners. The CH2018 scenarios will build primarily upon the latest Euro-CORDEX regional climate model simulations assuming different pathways of future greenhouse gas concentrations. Compared to CH2011, more emphasis will be put on changes in extremes and in putting the projected changes in the context of observed variability. Results of a recently conducted survey on end-user needs in Switzerland will guide the development process toward the CH2018 scenarios. It ensures that the scenarios are presented and communicated in a user-oriented format and find a wide applicability across different sectors in Switzerland. In the presentation we will show the full methodological setup to generate the CH2018 scenarios and how consistency across the methods and products is maximized. First results on mean changes and selected indices will be presented. In terms of dissemination, the results of the user survey show the necessity to address all different user types of climate scenarios, especially the non-experts. Compared to CH2011, this implies a stronger focus on consulting, condensing complex information and providing tutorials. In the presentation, we will outline our plans on dissemination in order to adequately

  13. CH/π Interactions in Carbohydrate Recognition.

    PubMed

    Spiwok, Vojtěch

    2017-06-23

    Many carbohydrate-binding proteins contain aromatic amino acid residues in their binding sites. These residues interact with carbohydrates in a stacking geometry via CH/π interactions. These interactions can be found in carbohydrate-binding proteins, including lectins, enzymes and carbohydrate transporters. Besides this, many non-protein aromatic molecules (natural as well as artificial) can bind saccharides using these interactions. Recent computational and experimental studies have shown that carbohydrate-aromatic CH/π interactions are dispersion interactions, tuned by electrostatics and partially stabilized by a hydrophobic effect in solvated systems.

  14. What’s Past is Prologue: A Scoping Review of Recent Public Health and Global Health Informatics Literature

    PubMed Central

    Dixon, Brian E.; Pina, Jamie; Kharrazi, Hadi; Gharghabi, Fardad; Richards, Janise

    2015-01-01

    Objective: To categorize and describe the public health informatics (PHI) and global health informatics (GHI) literature between 2012 and 2014. Methods: We conducted a semi-systematic review of articles published between January 2012 and September 2014 where information and communications technologies (ICT) was a primary subject of the study or a main component of the study methodology. Additional inclusion and exclusion criteria were used to filter PHI and GHI articles from the larger biomedical informatics domain. Articles were identified using MEDLINE as well as personal bibliographies from members of the American Medical Informatics Association PHI and GHI working groups. Results: A total of 85 PHI articles and 282 GHI articles were identified. While systems in PHI continue to support surveillance activities, we identified a shift towards support for prevention, environmental health, and public health care services. Furthermore, articles from the U.S. reveal a shift towards PHI applications at state and local levels. GHI articles focused on telemedicine, mHealth and eHealth applications. The development of adequate infrastructure to support ICT remains a challenge, although we identified a small but growing set of articles that measure the impact of ICT on clinical outcomes. Discussion: There is evidence of growth with respect to both implementation of information systems within the public health enterprise as well as a widening of scope within each informatics discipline. Yet the articles also illuminate the need for more primary research studies on what works and what does not as both searches yielded small numbers of primary, empirical articles. Conclusion: While the body of knowledge around PHI and GHI continues to mature, additional studies of higher quality are needed to generate the robust evidence base needed to support continued investment in ICT by governmental health agencies. PMID:26392846

  15. Development and Reliability Testing of the FEDS System for Classifying Glenohumeral Instability

    PubMed Central

    Kuhn, John E.; Helmer, Tara T.; Dunn, Warren R.; Throckmorton V, Thomas W.

    2010-01-01

    Background Classification systems for glenohumeral instability (GHI) are opinion based, not validated, and poorly defined. This study is designed to methodologically develop and test a GHI classification system. Methods: Classification System Development A systematic literature review identified 18 systems for classifying GHI. The frequency characteristics used was recorded. Additionally 31 members of the American Shoulder and Elbow Surgeons responded to a survey to identify features important to characterize GHI. Frequency, Etiology, Direction, and Severity (FEDS), were found to be most important. Frequency was defined as solitary (one episode), occasional (2–5x/year), or frequent (>5x/year). Etiology was defined as traumatic or atraumatic. Direction referred to the primary direction of instability (anterior, posterior, or inferior). Severity was defined as either subluxation or dislocation. Methods: Reliability Testing Fifty GHI patients completed a questionnaire at their initial visit. One of six sports medicine fellowship trained physicians completed a similar questionnaire after examining the patient. Patients returned after two weeks and were examined by the original physician and two other physicians. Inter- and intra-rater agreement for the FEDS classification system was calculated. Results Agreement between patients and physicians was lowest for frequency (39%; k=0.130) and highest for direction (82%; k=0.636). Physician intra-rater agreement was 84– 97% for the individual FEDS characteristics (k=0.69 to 0.87)). Physician inter-rater agreement ranged from 82–90% (k=0.44 to 0.76). Conclusions The FEDS system has content validity and is highly reliable for classifying GHI. Physical examination using provocative testing to determine the primary direction of instability produces very high levels of inter- and intra-rater agreement. Level of evidence Level II, Development of Diagnostic Criteria with Consecutive Series of Patients, Diagnosis Study. PMID

  16. Purification of nanogram-range immunoprecipitated DNA in ChIP-seq application.

    PubMed

    Zhong, Jian; Ye, Zhenqing; Lenz, Samuel W; Clark, Chad R; Bharucha, Adil; Farrugia, Gianrico; Robertson, Keith D; Zhang, Zhiguo; Ordog, Tamas; Lee, Jeong-Heon

    2017-12-21

    Chromatin immunoprecipitation-sequencing (ChIP-seq) is a widely used epigenetic approach for investigating genome-wide protein-DNA interactions in cells and tissues. The approach has been relatively well established but several key steps still require further improvement. As a part of the procedure, immnoprecipitated DNA must undergo purification and library preparation for subsequent high-throughput sequencing. Current ChIP protocols typically yield nanogram quantities of immunoprecipitated DNA mainly depending on the target of interest and starting chromatin input amount. However, little information exists on the performance of reagents used for the purification of such minute amounts of immunoprecipitated DNA in ChIP elution buffer and their effects on ChIP-seq data. Here, we compared DNA recovery, library preparation efficiency, and ChIP-seq results obtained with several commercial DNA purification reagents applied to 1 ng ChIP DNA and also investigated the impact of conditions under which ChIP DNA is stored. We compared DNA recovery of ten commercial DNA purification reagents and phenol/chloroform extraction from 1 to 50 ng of immunopreciptated DNA in ChIP elution buffer. The recovery yield was significantly different with 1 ng of DNA while similar in higher DNA amounts. We also observed that the low nanogram range of purified DNA is prone to loss during storage depending on the type of polypropylene tube used. The immunoprecipitated DNA equivalent to 1 ng of purified DNA was subject to DNA purification and library preparation to evaluate the performance of four better performing purification reagents in ChIP-seq applications. Quantification of library DNAs indicated the selected purification kits have a negligible impact on the efficiency of library preparation. The resulting ChIP-seq data were comparable with the dataset generated by ENCODE consortium and were highly correlated between the data from different purification reagents. This study provides

  17. Data exploration, quality control and statistical analysis of ChIP-exo/nexus experiments.

    PubMed

    Welch, Rene; Chung, Dongjun; Grass, Jeffrey; Landick, Robert; Keles, Sündüz

    2017-09-06

    ChIP-exo/nexus experiments rely on innovative modifications of the commonly used ChIP-seq protocol for high resolution mapping of transcription factor binding sites. Although many aspects of the ChIP-exo data analysis are similar to those of ChIP-seq, these high throughput experiments pose a number of unique quality control and analysis challenges. We develop a novel statistical quality control pipeline and accompanying R/Bioconductor package, ChIPexoQual, to enable exploration and analysis of ChIP-exo and related experiments. ChIPexoQual evaluates a number of key issues including strand imbalance, library complexity, and signal enrichment of data. Assessment of these features are facilitated through diagnostic plots and summary statistics computed over regions of the genome with varying levels of coverage. We evaluated our QC pipeline with both large collections of public ChIP-exo/nexus data and multiple, new ChIP-exo datasets from Escherichia coli. ChIPexoQual analysis of these datasets resulted in guidelines for using these QC metrics across a wide range of sequencing depths and provided further insights for modelling ChIP-exo data. © The Author(s) 2017. Published by Oxford University Press on behalf of Nucleic Acids Research.

  18. Direct Dynamics Simulation of Dissociation of the [CH3--I--OH]- Ion-Molecule Complex

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

    Xie, Jing; McClellan, Miranda; Sun, Rui

    Direct dynamics simulations were used to study dissociation of the [CH3--I--OH]- complex ion, which was observed in a previous study of the OH- + CH3I gas phase reaction (J. Phys. Chem. A 2013, 117, 7162). Restricted B97-1 simulations were performed to study dissociation at 65, 75 and 100 kcal/mol and the [CH3--I--OH]- ion dissociated exponentially, in accord with RRKM theory. For these energies the major dissociation products are CH3I + OH-, CH2I- + H2O, and CH3OH + I-. Unrestricted B97-1 and restricted and unrestricted CAM-B3LYP simulations were also performed at 100 kcal/mol to compare with the restricted B97-1 results. Themore » {CH3I + OH-}:{CH2I- + H2O}:{CH3OH + I-} product ratio is 0.72 : 0.15 : 0.13, 0.81 : 0.05 : 0.14, 0.71 : 0.19 : 0.10 , and 0.83 : 0.13 : 0.04 for the restricted B97-1, unrestricted B97-1, restricted CAM-B3LYP, and unrestricted CAM-B3LYP simulations, respectively. Other product channels found are CH2 + I- + H2O, CH2 + I-(H2O), CH4 + IO-, CH3 - + IOH, and CH3 + IOH-. The CH3 - + IOH singlet products are only given by the restricted B97-1 simulation and the lower energy CH3 + IOH- doublet products are only formed by the unrestricted B97-1 simulation. Also studied were the direct and indirect atomic-level mechanisms for forming CH3I + OH-, CH2I- + H2O, and CH3OH + I-. The majority of CH3I + OH- were formed through a direct mechanism. For both CH2I- + H2O and CH3OH + I-, the direct mechanism is overall more important than the indirect mechanisms, with the round-about like mechanism the most important indirect mechanism at high excitation energies. Mechanism comparisons between the B97-1 and CAM-B3LYP simulations showed that formation of the CH3OH---I- complex is favored for the B97-1 simulations, while formation of the HO----HCH2I complex is favored for the CAM-B3LYP simulations. The unrestricted simulations give a higher percentage of indirect mechanisms than the restricted simulations. The possible role of the self-interaction error in

  19. Short-Term Global Horizontal Irradiance Forecasting Based on Sky Imaging and Pattern Recognition

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

    Hodge, Brian S; Feng, Cong; Cui, Mingjian

    Accurate short-term forecasting is crucial for solar integration in the power grid. In this paper, a classification forecasting framework based on pattern recognition is developed for 1-hour-ahead global horizontal irradiance (GHI) forecasting. Three sets of models in the forecasting framework are trained by the data partitioned from the preprocessing analysis. The first two sets of models forecast GHI for the first four daylight hours of each day. Then the GHI values in the remaining hours are forecasted by an optimal machine learning model determined based on a weather pattern classification model in the third model set. The weather pattern ismore » determined by a support vector machine (SVM) classifier. The developed framework is validated by the GHI and sky imaging data from the National Renewable Energy Laboratory (NREL). Results show that the developed short-term forecasting framework outperforms the persistence benchmark by 16% in terms of the normalized mean absolute error and 25% in terms of the normalized root mean square error.« less

  20. Scalable and sustainable electrochemical allylic C-H oxidation

    NASA Astrophysics Data System (ADS)

    Horn, Evan J.; Rosen, Brandon R.; Chen, Yong; Tang, Jiaze; Chen, Ke; Eastgate, Martin D.; Baran, Phil S.

    2016-05-01

    New methods and strategies for the direct functionalization of C-H bonds are beginning to reshape the field of retrosynthetic analysis, affecting the synthesis of natural products, medicines and materials. The oxidation of allylic systems has played a prominent role in this context as possibly the most widely applied C-H functionalization, owing to the utility of enones and allylic alcohols as versatile intermediates, and their prevalence in natural and unnatural materials. Allylic oxidations have featured in hundreds of syntheses, including some natural product syntheses regarded as “classics”. Despite many attempts to improve the efficiency and practicality of this transformation, the majority of conditions still use highly toxic reagents (based around toxic elements such as chromium or selenium) or expensive catalysts (such as palladium or rhodium). These requirements are problematic in industrial settings; currently, no scalable and sustainable solution to allylic oxidation exists. This oxidation strategy is therefore rarely used for large-scale synthetic applications, limiting the adoption of this retrosynthetic strategy by industrial scientists. Here we describe an electrochemical C-H oxidation strategy that exhibits broad substrate scope, operational simplicity and high chemoselectivity. It uses inexpensive and readily available materials, and represents a scalable allylic C-H oxidation (demonstrated on 100 grams), enabling the adoption of this C-H oxidation strategy in large-scale industrial settings without substantial environmental impact.

  1. Valorization of CH4 emissions into high-added-value products: Assessing the production of ectoine coupled with CH4 abatement.

    PubMed

    Cantera, Sara; Lebrero, Raquel; Sadornil, Lidia; García-Encina, Pedro A; Muñoz, Raúl

    2016-11-01

    This study assessed an innovative strategy for the valorization of dilute methane emissions based on the bio-conversion of CH4 (the second most important greenhouse gas (GHG)) into ectoine by the methanotrophic ectoine-producing strain Methylomicrobium alcaliphilum 20 Z. The influence of CH4 (2-20%), Cu(2+) (0.05-50 μM) and NaCl (0-9%) concentration as well as temperature (25-35 °C) on ectoine synthesis and specific CH4 biodegradation rate was evaluated for the first time. Concentrations of 20% CH4 (at 3% NaCl, 0.05 μM Cu(2+), 25 °C) and 6% NaCl (at 4% CH4, 0.05 μM Cu(2+), 25 °C) supported the maximum intra-cellular ectoine production yield (31.0 ±1.7 and 66.9 ±4.2 mg g biomass(-1), respectively). On the other hand, extra-cellular ectoine concentrations of up to 4.7 ± 0.1 mg L(-1) were detected at high Cu(2+)concentrations (50 μM), despite this methanotroph has not been previously classified as an ectoine-excreting strain. This research demonstrated the feasibility of the bio-conversion of dilute emissions of methane into high-added value products in an attempt to develop a sustainable GHG bioeconomy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Satellite Boreal Measurements over Alaska and Canada During June-July 2004: Simultaneous Measurements of Upper Tropospheric CO, C2H6, HCN, CH3Cl, CH4, C2H2, CH2OH, HCOOH, OCS, and SF6 Mixing Ratios

    NASA Technical Reports Server (NTRS)

    Rinsland, Curtis P.; Dufour, Gaelle; Boone, Chris D.; Bernath, Peter F.; Chiou, Linda; Coheur, Pierre-Francois; Turquety, Solene; Clerbaux, Cathy

    2007-01-01

    Simultaneous ACE (Atmospheric Chemistry Experiment) upper tropospheric CO, C2H6, HCN, CH3Cl, CH4 , C2H2 , CH30H, HCOOH, and OCS measurements show plumes up to 185 ppbv (10 (exp -9) per unit volume) for CO, 1.36 ppbv for C2H6, 755 pptv (10(exp -12) per unit volume) for HCN, 1.12 ppbv for CH3C1, 1.82 ppmv, (10(exp -6) per unit volume) for CH4, 0.178 ppbv for C2H2, 3.89 ppbv for CH30H, 0.843 ppbv for HCOOH, and 0.48 ppbv for OCS in western Canada and Alaska at 50 deg N-68 deg N latitude between 29 June and 23 July 2004. Enhancement ratios and emission factors for HCOOH, CH30H, HCN, C2H6, and OCS relative to CO at 250-350 hPa are inferred from measurements of young plumes compared with lower mixing ratios assumed to represent background conditions based on a CO emission factor derived from boreal measurements. Results are generally consistent with the limited data reported for various vegetative types and emission phases measured in extratropical forests including boreal forests. The low correlation between fire product emission mixing ratios and the S176 mixing ratio is consistent with no significant SF6 emissions from the biomass fires.

  3. Hydrothermal plumes in the Gulf of Aden, as characterized by light transmission, Mn, Fe, CH4 and δ13C-CH4 anomalies

    NASA Astrophysics Data System (ADS)

    Gamo, Toshitaka; Okamura, Kei; Hatanaka, Hiroshi; Hasumoto, Hiroshi; Komatsu, Daisuke; Chinen, Masakazu; Mori, Mutsumi; Tanaka, Junya; Hirota, Akinari; Tsunogai, Urumu; Tamaki, Kensaku

    2015-11-01

    We conducted water column surveys to search for hydrothermal plumes over the spreading axes in the Gulf of Aden between 45°35‧E and 52°42‧E. We measured light transmission and chemical tracers Mn, Fe, CH4 and δ13C of CH4 in seawater taken using a CTD-Carrousel multi-sampling system at 12 locations including a control station in the Arabian Sea. We recognized three types of hydrothermal plumes at depths of 650 to 900 m (shallow plumes), 1000 to 1200 m (intermediate plumes), and >1500 m (deep plumes). The shallow plumes were apparently originated from newly discovered twin seamounts (12°03-06‧N and 45°35-41‧E) at the westernmost survey area, where two-dimensional distributions of light transmission and Mn were mapped by tow-yo observations of the CTD-sampling system with an in situ auto-analyzer GAMOS. The maximum concentrations of Mn, Fe, and CH4 of 46 nM, 251 nM, and 15 nM, respectively, were observed for collected seawater within the shallow plumes. The intermediate plumes were characterized by anomalies of light transmission, Mn, Fe, and δ13C of CH4, but by little CH4 anomalies, suggesting that CH4 had been consumed down to the background level during the aging of the plumes. Anomalies of δ3He already reported by the World Ocean Circulation Experiment (WOCE) program exhibited a hydrothermal plume-like peak at 2000 m depth in the Gulf of Aden, which seems to coincide with the deep plumes observed in this study. The endmember δ13C-CH4 values for the shallow and the deep plumes were estimated to be in a range between -10‰ and -15‰, demonstrating that the sources of CH4 are not biogenic but magmatic as similarly observed at sediment-starved mid-oceanic ridges.

  4. Hospital clinical trial: Homeopathy (Agraphis nutans 5CH, Thuya occidentalis 5CH, Kalium muriaticum 9CH and Arsenicum iodatum 9CH) as adjuvant, in children with otitis media with effusion.

    PubMed

    Pedrero-Escalas, M F; Jimenez-Antolin, J; Lassaletta, L; Diaz-Saez, G; Gavilán, J

    2016-09-01

    Otitis media with effusion (OME) is the most common cause of paediatric hearing loss. No single treatment has proved its effectiveness. There is a lack of evidence-based medicine studies in the area of homeopathy. A prospective randomized, double blinded interventional placebo control study was conducted. Patients, from 2 months to 12 years, with OME diagnosed by pneumatic otoscopy (PNO) and tympanometry, were randomized into two groups. Both groups received aerosol therapy (mucolytics and corticosteroids). In addition, the experimental group (EG) received homeopathy (Agraphis nutans 5CH, Thuya Occidentalis 5CH, Kalium muriaticum 9CH and Arsenicum iodatum), and the placebo group (PG) placebo, both of them for 3 months. Patients were evaluated by PNO examination and tympanometry at baseline, at 45 and 90 days. 97 patients were enrolled. In the EG, 61.9% of individuals were cured (PNO went from negative in the 1st visit to positive in the 3rd visit) compared with 56.8% of patients treated with placebo. 4.8% of patients in the EG suffered a recurrence (positive PNO in the 2nd visit changed to negative in the 3rd visit) while 11.4% did in the PG. No significant difference was found. Adverse events were distributed similarly, except in the case of upper respiratory tract infections, which were less frequent in EG (3 vs. 13, p: 0.009). The homeopathic scheme used as adjuvant treatment cannot be claimed to be an effective treatment in children with OME. EUDRACT number: 2011-006086-17, PROTOCOL code: 55005646. Copyright © 2016 Elsevier Ireland Ltd. All rights reserved.

  5. Electronic structure, transport, and phonons of SrAg ChF ( Ch = S,Se,Te): Bulk superlattice thermoelectrics

    DOE PAGES

    Gudelli, Vijay Kumar; Kanchana, V.; Vaitheeswaran, G.; ...

    2015-07-15

    Here, we report calculations of the electronic structure, vibrational properties, and transport for the p-type semiconductors, SrAg ChF ( Ch = S, Se, and Te). We find soft phonons with low frequency optical branches intersecting the acoustic modes below 50 cm –1, indicative of a material with low thermal conductivity. The bands at and near the valence-band maxima are highly two-dimensional, which leads to high thermopowers even at high carrier concentrations, which is a combination that suggests good thermoelectric performance. These materials may be regarded as bulk realizations of superlattice thermoelectrics.

  6. [CH(3)(CH(2))(11)NH(3)]SnI(3): a hybrid semiconductor with MoO(3)-type tin(II) iodide layers.

    PubMed

    Xu, Zhengtao; Mitzi, David B

    2003-10-20

    The organic-inorganic hybrid [CH(3)(CH(2))(11)NH(3)]SnI(3) presents a lamellar structure with a Sn-I framework isotypic to that of MoO(3). The SnI(3)(-) layer consists of edge and corner-sharing SnI(6) octahedra in which one of the six Sn-I bonds is distinctly elongated (e.g., 3.62 A), indicating lone-pair stereoactivity for the Sn(II) atom. The overall electronic character remains comparable with that of the well-studied SnI(4)(2)(-)-based perovskite semiconductors, such as [CH(3)(CH(2))(11)NH(3)](2)SnI(4), with a red-shifted and broadened exciton peak associated with the band gap, apparently due to the increased dimensionality of the Sn-I framework. The title compound offers, aside from the hybrid perovskites, a new type of solution-processable Sn-I network for potential applications in semiconductive devices.

  7. Biologic properties of a CH2 domain-deleted recombinant immunoglobulin.

    PubMed

    Slavin-Chiorini, D C; Horan Hand, P H; Kashmiri, S V; Calvo, B; Zaremba, S; Schlom, J

    1993-01-02

    Monoclonal antibody (MAb) B72.3 reacts with TAG-72, a high-molecular-weight mucin expressed on several types of human carcinoma, and is currently being used in clinical trials for the diagnosis and therapy of human carcinoma. An expression construct containing cDNA encoding an immunoglobulin (Ig) heavy chain, with the variable region of murine MAb B72.3 and a human Ig constant region with a deletion of the CH2 domain, was generated. Immunoglobulin from the transfectoma with the highest expression of the TAG-72 immunoreactive antibody was designated MAb chimeric (c) B72.3 delta CH2. The pharmacokinetics of serum clearance of iodine-labeled MAbs cB72.3 delta CH2 and the intact cB72.3 were compared in athymic mice. By 24 hr, less than 1% of the cB72.3 delta CH2 was left in the plasma, while 36% of the cB72.3 still remained. The T1/2 alpha values of the cB72.3 delta CH2 and cB72.3 MAbs were 1.7 and 2.4 hr, respectively. The T1/2 beta values were 7.8 hr for the domain-deleted cMAb and 48.9 hr for cB72.3. Biodistribution studies in athymic mice bearing LS-174T xenografts showed a reduction in the percentage of injected dose per gram in tumor with 131I-cB72.3 delta CH2; however, the 131I-cB72.3 delta CH2 both localized to tumors faster and cleared from the blood faster than the 125I-cB72.3 MAb. Only trace amounts of the 131I-cB72.3 delta CH2 were detected in normal tissues, including kidney. The faster clearance rate, more rapid tumor targeting and lack of metabolic uptake in normal tissues demonstrated with the iodine-labeled CH2 domain-deleted cMAb may be an advantage for certain clinical protocols.

  8. CH-47F Improved Cargo Helicopter (CH-47F)

    DTIC Science & Technology

    2015-12-01

    Confidence Level Confidence Level of cost estimate for current APB: 50% The Confidence Level of the CH-47F APB cost estimate, which was approved on April...M) Initial PAUC Development Estimate Changes PAUC Production Estimate Econ Qty Sch Eng Est Oth Spt Total 10.316 -0.491 3.003 -0.164 2.273 7.378...SAR Baseline to Current SAR Baseline (TY $M) Initial APUC Development Estimate Changes APUC Production Estimate Econ Qty Sch Eng Est Oth Spt Total

  9. Glycosides derived from Hemidesmus indicus R. Br. root inhibit adherence of Salmonella typhimurium to host cells: receptor mimicry.

    PubMed

    Das, Sarita; Devaraj, S Niranjali

    2006-09-01

    For centuries, indigenous plants have been used against enteritis but their molecular targets and mode of action remain obscure. The present study was carried out to elucidate the protective and therapeutic role, if any, of glycosides from Hemidesmus indicus against S. typhimurium-induced pathogenesis. Studies were carried out in a human intestinal cell line (Int 407) and a murine macrophage cell line (P388D1) in order to evaluate its potency in local as well as systemic infections. The inhibitory role of the glycosides present in Hemidesmus indicus root extract (GHI) were tested by pre-coating the cells (both Int 407 and P388D1) with GHI prior to infection, and by neutralizing the wild-type bacteria with GHI before cell infection. In both cases, GHI protected the host cells from the cytotoxic effects of the wild S. typhimurium. This suggests that the biologically significant sugars (hexose, hexosamine, fucose and sialic acid etc) present in GHI might be mimicking host cell receptor saccharides and thereby blocking the bacterial ligands from binding to the host cells. Int 407 cells infected with wild-type bacteria had a diffused adherence pattern after 4 h incubation, but this typical character was not observed in cells infected with GHI-treated bacteria and the cells were normal in appearance at 4 h. After 18 h cells infected with wild-type bacteria were hypertrophoid with a disintegrated membrane and wrapped in a bacterial coat, whereas cells infected with treated bacteria had comparatively less morphological changes and few defective shrunken rods adhered locally. This suggests that the glycosides can change the adherence pattern of S. typhimurium from diffused to local. Treated bacteria had less adherence and invasion capability in Int 407 as well as P388D1 cells. The results show the decreased ability of adherence of GHI-treated S. typhimurium was due to a loss of surface hydrophobicity. A nonspecific binding between S. typhimurium and the glycosides was

  10. Microheterogeneity in CH3OH/CD3OH mixture

    NASA Astrophysics Data System (ADS)

    Wrzeszcz, Władysław; Mazurek, Sylwester; Szostak, Roman; Tomza, Paweł; Czarnecki, Mirosław A.

    2018-01-01

    Recently, we demonstrated the presence of microheterogeneity in binary mixtures of unlike alcohols. [RSC Adv. 2016, 6, 37195-37202] The aim of this work was examination if this phenomenon occurs also in the mixture of very similar alcohols like CH3OH and CD3OH. Theoretical calculations suggest that the isotopic substitution in methyl group influences properties of the OH group. Hence, one can expect that this effect may lead to partial separation of CH3OH and CD3OH at a molecular level and it contributes to deviation from the ideal mixture. This work evidences that CH3OH/CD3OH mixture also deviates from the ideal one, but the extent of this deviation is much smaller as compared with the mixtures of other alcohols. It is of particular note that this deviation results mainly from the difference between the CH3 and CD3 groups, while the contribution from the OH groups is small. The structure of CH3OH/CD3OH mixture at a molecular level is similar to the structure of binary mixtures of other alcohols. The mixture is composed of the homoclusters of both alcohols and the mixed clusters. The homoclusters existing in the mixture are similar to those present in bulk alcohols. The highest population of the heteroclusters and the largest deviation from the ideal mixture were observed at equimolar mixture. Both the experimental and theoretical results reveal that in CH3OH/CD3OH mixture dominate the cyclic tetramers and larger clusters, while the population of the linear clusters is negligible. Though the extent and strength of hydrogen bonding in both alcohols are the same, the position and intensity of the 2ν(OH) band for CH3OH and CD3OH are different. We propose possible explanation of this observation.

  11. ChIP-seq and ChIP-exo profiling of Pol II, H2A.Z, and H3K4me3 in human K562 cells.

    PubMed

    Mchaourab, Zenab F; Perreault, Andrea A; Venters, Bryan J

    2018-03-06

    The human K562 chronic myeloid leukemia cell line has long served as an experimental paradigm for functional genomic studies. To systematically and functionally annotate the human genome, the ENCODE consortium generated hundreds of functional genomic data sets, such as chromatin immunoprecipitation coupled to sequencing (ChIP-seq). While ChIP-seq analyses have provided tremendous insights into gene regulation, spatiotemporal insights were limited by a resolution of several hundred base pairs. ChIP-exonuclease (ChIP-exo) is a refined version of ChIP-seq that overcomes this limitation by providing higher precision mapping of protein-DNA interactions. To study the interplay of transcription initiation and chromatin, we profiled the genome-wide locations for RNA polymerase II (Pol II), the histone variant H2A.Z, and the histone modification H3K4me3 using ChIP-seq and ChIP-exo. In this Data Descriptor, we present detailed information on parallel experimental design, data generation, quality control analysis, and data validation. We discuss how these data lay the foundation for future analysis to understand the relationship between the occupancy of Pol II and nucleosome positions at near base pair resolution.

  12. Experimental binding energies for the metal complexes [Mg(CH3OH)n](2+), [Ca(CH3OH)n](2+), and [Sr(CH3OH)n](2+) for n in the range 4-20.

    PubMed

    Bruzzi, E; Stace, A J

    2014-10-09

    A supersonic source of clusters has been used to prepare neutral complexes of methanol in association with an alkaline earth metal atom. From these complexes the following metal-containing dications have been generated through electron ionization: [Mg(CH3OH)n](2+), [Ca(CH3OH)n](2+), and [Sr(CH3OH)n](2+), and for n in the range 4-20, kinetic energy release measurements following the evaporation of a single molecule have been undertaken using a high resolution mass spectrometer. Using finite heat bath theory, these data have been transformed into binding energies for individual methanol molecules attached to each of the three cluster systems. In the larger complexes (n > 6) the results exhibit a consistent trend, whereby the experimental binding energy data for all three metal ions are similar, suggesting that the magnitude of the charge rather than charge density influences the strength of the interaction. From a comparison with data recorded previously for (CH3OH)nH(+) it is found that the 2+ charge on a metal ion has an effect on the binding energy of molecules in complexes containing up to 20 solvent molecules. The results recorded for [Ca(CH3OH)n](2+) show evidence of a very marked transition between n = 6 and 7, which is thought to coincide with the completion of a primary solvation shell and the onset of molecules starting to occupy a second and most probably a third shell.

  13. Chætognath transcriptome reveals ancestral and unique features among bilaterians

    PubMed Central

    Marlétaz, Ferdinand; Gilles, André; Caubit, Xavier; Perez, Yvan; Dossat, Carole; Samain, Sylvie; Gyapay, Gabor; Wincker, Patrick; Le Parco, Yannick

    2008-01-01

    Background The chætognaths (arrow worms) have puzzled zoologists for years because of their astonishing morphological and developmental characteristics. Despite their deuterostome-like development, phylogenomic studies recently positioned the chætognath phylum in protostomes, most likely in an early branching. This key phylogenetic position and the peculiar characteristics of chætognaths prompted further investigation of their genomic features. Results Transcriptomic and genomic data were collected from the chætognath Spadella cephaloptera through the sequencing of expressed sequence tags and genomic bacterial artificial chromosome clones. Transcript comparisons at various taxonomic scales emphasized the conservation of a core gene set and phylogenomic analysis confirmed the basal position of chætognaths among protostomes. A detailed survey of transcript diversity and individual genotyping revealed a past genome duplication event in the chætognath lineage, which was, surprisingly, followed by a high retention rate of duplicated genes. Moreover, striking genetic heterogeneity was detected within the sampled population at the nuclear and mitochondrial levels but cannot be explained by cryptic speciation. Finally, we found evidence for trans-splicing maturation of transcripts through splice-leader addition in the chætognath phylum and we further report that this processing is associated with operonic transcription. Conclusion These findings reveal both shared ancestral and unique derived characteristics of the chætognath genome, which suggests that this genome is likely the product of a very original evolutionary history. These features promote chætognaths as a pivotal model for comparative genomics, which could provide new clues for the investigation of the evolution of animal genomes. PMID:18533022

  14. High-resolution sub-Doppler infrared spectroscopy of atmospherically relevant Criegee precursor CH2I radicals: CH2 stretch vibrations and "charge-sloshing" dynamics

    NASA Astrophysics Data System (ADS)

    Kortyna, A.; Lesko, D. M. B.; Nesbitt, D. J.

    2018-05-01

    The combination of a pulsed supersonic slit-discharge source and single-mode difference frequency direct absorption infrared spectroscopy permit first high resolution infrared study of the iodomethyl (CH2I) radical, with the CH2I radical species generated in a slit jet Ne/He discharge and cooled to 16 K in the supersonic expansion. Dual laser beam detection and collisional collimation in the slit expansion yield sub-Doppler linewidths (60 MHz), an absolute frequency calibration of 13 MHz, and absorbance sensitivities within a factor of two of the shot-noise limit. Fully rovibrationally resolved direct absorption spectra of the CH2 symmetric stretch mode (ν2) are obtained and fitted to a Watson asymmetric top Hamiltonian with electron spin-rotation coupling, providing precision rotational constants and spin-rotation tensor elements for the vibrationally excited state. Analysis of the asymmetric top rotational constants confirms a vibrationally averaged planar geometry in both the ground- and first-excited vibrational levels. Sub-Doppler resolution permits additional nuclear spin hyperfine structures to be observed, with splittings in excellent agreement with microwave measurements on the ground state. Spectroscopic data on CH2I facilitate systematic comparison with previous studies of halogen-substituted methyl radicals, with the periodic trends strongly correlated with the electronegativity of the halogen atom. Interestingly, we do not observe any asymmetric CH2 stretch transitions, despite S/N ≈ 25:1 on strongest lines in the corresponding symmetric CH2 stretch manifold. This dramatic reversal of the more typical 3:1 antisymmetric/symmetric CH2 stretch intensity ratio signals a vibrational transition moment poorly described by simple "bond-dipole" models. Instead, the data suggest that this anomalous intensity ratio arises from "charge sloshing" dynamics in the highly polar carbon-iodine bond, as supported by ab initio electron differential density plots and

  15. Limitations and possibilities of low cell number ChIP-seq

    PubMed Central

    2012-01-01

    Background Chromatin immunoprecipitation coupled with high-throughput DNA sequencing (ChIP-seq) offers high resolution, genome-wide analysis of DNA-protein interactions. However, current standard methods require abundant starting material in the range of 1–20 million cells per immunoprecipitation, and remain a bottleneck to the acquisition of biologically relevant epigenetic data. Using a ChIP-seq protocol optimised for low cell numbers (down to 100,000 cells / IP), we examined the performance of the ChIP-seq technique on a series of decreasing cell numbers. Results We present an enhanced native ChIP-seq method tailored to low cell numbers that represents a 200-fold reduction in input requirements over existing protocols. The protocol was tested over a range of starting cell numbers covering three orders of magnitude, enabling determination of the lower limit of the technique. At low input cell numbers, increased levels of unmapped and duplicate reads reduce the number of unique reads generated, and can drive up sequencing costs and affect sensitivity if ChIP is attempted from too few cells. Conclusions The optimised method presented here considerably reduces the input requirements for performing native ChIP-seq. It extends the applicability of the technique to isolated primary cells and rare cell populations (e.g. biobank samples, stem cells), and in many cases will alleviate the need for cell culture and any associated alteration of epigenetic marks. However, this study highlights a challenge inherent to ChIP-seq from low cell numbers: as cell input numbers fall, levels of unmapped sequence reads and PCR-generated duplicate reads rise. We discuss a number of solutions to overcome the effects of reducing cell number that may aid further improvements to ChIP performance. PMID:23171294

  16. An eight-dimensional quantum dynamics study of the Cl + CH{sub 4}→ HCl + CH{sub 3} reaction

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

    Liu, Na; Yang, Minghui, E-mail: yangmh@wipm.ac.cn

    2015-10-07

    In this work, the later-barrier reaction Cl + CH{sub 4} → HCl + CH{sub 3} is investigated with an eight-dimensional quantum dynamics method [R. Liu et al., J. Chem. Phys. 137, 174113 (2012)] on the ab initio potential energy surface of Czakó and Bowman [J. Chem. Phys. 136, 044307 (2012)]. The reaction probabilities with CH{sub 4} initially in its ground and vibrationally excited states are calculated with a time-dependent wavepacket method. The theoretical integral cross sections (ICSs) are extensively compared with the available experimental measurements. For the ground state reaction, the theoretical ICSs excellently agree with the experimental ones. Themore » good agreements are also achieved for ratios between ICSs of excited reactions. For ICS ratios between various states, the theoretical values are also consistent with the experimental observations. The rate constants over 200-2000 K are calculated and the non-Arrhenius effect has been observed which is coincident with the previous experimental observations and theoretical calculations.« less

  17. ChIPBase: a database for decoding the transcriptional regulation of long non-coding RNA and microRNA genes from ChIP-Seq data.

    PubMed

    Yang, Jian-Hua; Li, Jun-Hao; Jiang, Shan; Zhou, Hui; Qu, Liang-Hu

    2013-01-01

    Long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) represent two classes of important non-coding RNAs in eukaryotes. Although these non-coding RNAs have been implicated in organismal development and in various human diseases, surprisingly little is known about their transcriptional regulation. Recent advances in chromatin immunoprecipitation with next-generation DNA sequencing (ChIP-Seq) have provided methods of detecting transcription factor binding sites (TFBSs) with unprecedented sensitivity. In this study, we describe ChIPBase (http://deepbase.sysu.edu.cn/chipbase/), a novel database that we have developed to facilitate the comprehensive annotation and discovery of transcription factor binding maps and transcriptional regulatory relationships of lncRNAs and miRNAs from ChIP-Seq data. The current release of ChIPBase includes high-throughput sequencing data that were generated by 543 ChIP-Seq experiments in diverse tissues and cell lines from six organisms. By analysing millions of TFBSs, we identified tens of thousands of TF-lncRNA and TF-miRNA regulatory relationships. Furthermore, two web-based servers were developed to annotate and discover transcriptional regulatory relationships of lncRNAs and miRNAs from ChIP-Seq data. In addition, we developed two genome browsers, deepView and genomeView, to provide integrated views of multidimensional data. Moreover, our web implementation supports diverse query types and the exploration of TFs, lncRNAs, miRNAs, gene ontologies and pathways.

  18. Large CH4 production fueled by autochthonous OC in an anoxic sediment

    NASA Astrophysics Data System (ADS)

    Grasset, Charlotte; Mendonça, Raquel; Villamor Saucedo, Gabriella; Sobek, Sebastian

    2017-04-01

    River damming and human-induced eutrophication both affect river and lake functioning, increase organic carbon (OC) sedimentation rates and generate anoxic conditions in bottom waters. Under these conditions, OC in sediments is decomposed into CO2 and CH4, a high potential greenhouse gas. It has been shown that the decomposition of land-derived (allochthonous) OC is inhibited at anoxic conditions, compared to OC internally produced (autochthonous). However, the overall extent and end products (CO2 or CH4) of anoxic decomposition remain poorly known for different types of OC, making it difficult to judge the effect of river damming and eutrophication on greenhouse gas emissions from inland waters. We incubated different types of allochthonous OC (terrestrial plants) and autochthonous OC (phytoplankton and aquatic vascular plants) in an anoxic sediment during 130 days. We aimed to test 1) if this addition of relatively fresh OC resulted in an increase of CH4 production and 2) if autochthonous OC would produce more CH4 than allochthonous OC. We assessed the contribution to CH4 production of the different OC sources (i.e. sediment or added OC) with stable isotope measurements. We found that the addition of relatively fresh OC greatly increased CH4 production. Autochthonous OC generally produced more CH4 than allochthonous OC, but the overall extent of CH4 production was highly variable between the different autochthonous OC types. The d13C-CH4 measurements indicated that CH4 originated exclusively from the added OC. We conclude that the production of CH4 is likely to to be high in eutrophic as well as in artificial lakes, especially when these systems have anoxic bottom waters and high internal primary productivity and thus a high supply of autochthonous OC to the sediment. The current expansion of reservoir construction in concert with almost globally prevalent anthropogenic eutrophication are therefore likely to increase CH4 production in inland waters.

  19. Warming Early Mars With CH4

    NASA Astrophysics Data System (ADS)

    Justh, H. L.; Kasting, J. F.

    2002-12-01

    The nature of the ancient climate of Mars remains one of the fundamental unresolved problems in martian research. While the present environment is hostile to life, images from the Mariner, Viking and Mars Global Surveyor missions, have shown geologic features on the martian surface that seem to indicate an earlier period of hydrologic activity. The fact that ancient valley networks and degraded craters have been seen on the martian surface indicates that the early martian climate may have been more Earth-like, with a warmer surface temperature. The presence of liquid water would require a greenhouse effect much larger than needed at present, as the solar constant, S0, was 25% lower 3.8 billion years ago when the channels are thought to have formed (1,2). Previous calculations have shown that gaseous CO2 and H2O alone could not have warmed the martian surface to the temperature needed to account for the presence of liquid water (3). It has been hypothesized that a CO2-H2O atmosphere could keep early Mars warm if it was filled with CO2 ice clouds in the upper martian troposphere (4). Obtaining mean martian surface temperatures above 273 K would require nearly 100% cloud cover, a condition that is unrealistic for condensation clouds on early Mars. Any reduction in cloud cover makes it difficult to achieve warm martian surface temperatures except at high pressures and CO2 clouds could cool the martian surface if they were low and optically thick (5). CO2 and CH4 have been suggested as important greenhouse gases on the early Earth. Our research focuses on the effects of increased concentrations of atmospheric greenhouse gases on the surface temperature of early Mars, with emphasis on the reduced greenhouse gas, CH4. To investigate the possible warming effect of CH4, we modified a one-dimensional, radiative-convective climate model used in previous studies of the early martian climate (5). New cloud-free temperature profiles for various surface pressures and CH4 mixing

  20. Was Early Mars Warmed by CH4?

    NASA Astrophysics Data System (ADS)

    Justh, H. L.; Kasting, J. F.

    2001-12-01

    Images from the Mariner, Viking and Mars Global Surveyor missions have shown geologic features on the Martian surface that seem to indicate an earlier period of hydrologic activity. Many researchers have suggested that the early Martian climate was more Earth-like with a Ts of 273 K or higher. The presence of liquid water would require a greenhouse effect much larger than needed at present since S0 is 25% lower 3.8 billion years ago when the channels are thought to have formed. Research into the effects of CO2 clouds upon the climate of early Mars have yielded results that would not effectively warm the surface to the temperature needed to account for the presence of liquid water. Forget and Pierrehumbert (Science, 1997) showed that large crystals of CO2 ice in clouds that form in the upper troposphere would produce a strong warming effect. Obtaining mean surface temperatures above 273 K would require 100% cloud cover, a condition that is unrealistic for early Mars. It has also been shown that any reduction in cloud cover makes it difficult to achieve warm Martian surface temperatures except at high pressures. CO2 clouds could also cool the Martian surface if they were low and optically thick. CO2 ice may be hard to nucleate, leading to the formation of very large particles (Glandorf, private communication). CH4 has been suggested as an important greenhouse gas on the early Earth. This has led us to look at CH4 as a potential solution to the early Mars climate issue. To investigate the possible warming effect of CH4, we utilized a modified, one-dimensional, radiative-convective climate model that has been used in previous studies of the early Martian climate. New calculations of the effects of CH4 upon the early Martian climate will be presented. The use of CH4 to warm the surface of early Mars does not necessarily imply the presence of life on Mars. Abiotic sources of CH4, such as serpentinization of ultramafic rocks, could supply the concentrations needed to warm

  1. Food residue recycling by swine breeders in a developing economy: a case study in Da Nang, Viet Nam.

    PubMed

    Kato, Takaaki; Pham, Dung Thi Xuan; Hoang, Hai; Xue, Yonghai; Tran, Quang Van

    2012-12-01

    This study provides a detailed description of food residue collection by swine breeders in Da Nang, Viet Nam. In January 2011, the study surveyed 30 swine breeders in two villages with respect to locations, methods, prices, quantities, and prospects for food residue collection. The sampled swine breeders regularly visited 55 locations in central Da Nang to collect raw food residue. They then transferred the food residue to their piggeries, boiled it, and fed it to their swine. A regression analysis revealed that the total amount of food residue collected by a farm depends on the number of swine in the farm and the number of collections made per day. Swine breeders in Da Nang were estimated to collect 26.3 metric tons of organic waste per day, which amounted to 4.1% of domestic waste collected by the local government. Among the sampled swine breeders, 93% answered that they would continue using food residue for the next five years. Copyright © 2012 Elsevier Ltd. All rights reserved.

  2. Risk Behaviors for HIV and HCV Infection Among People Who Inject Drugs in Hai Phong, Viet Nam, 2014.

    PubMed

    Duong, Huong Thi; Jarlais, Don Des; Khuat, Oanh Hai Thi; Arasteh, Kamyar; Feelemyer, Jonathan; Khue, Pham Minh; Giang, Hoang Thi; Laureillard, Didier; Hai, Vinh Vu; Vallo, Roselyne; Michel, Laurent; Moles, Jean Pierre; Nagot, Nicolas

    2017-06-13

    We examined the potential for HIV and hepatitis C (HCV) transmission across persons who inject drugs (PWID), men-who-have-sex-with-men (MSM) and female commercial sex workers (CSW) PWID and the potential for sexual transmission of HIV from PWID to the general population in Hai Phong, Viet Nam. Using respondent driven and convenience sampling we recruited 603 participants in 2014. All participants used heroin; 24% used non-injected methamphetamine. HIV prevalence was 25%; HCV prevalence was 67%. HIV infection was associated with HCV prevalence and both infections were associated with length of injecting career. Reported injecting risk behaviors were low; unsafe sexual behavior was high among MSM-PWID and CSW-PWID. There is strong possibility of sexual transmission to primary partners facilitated by methamphetamine use. We would suggest future HIV prevention programs utilize multiple interventions including "treatment as prevention" to potential sexual transmission of HIV among MSM and CSW-PWID and from PWID to the general population.

  3. The mangrove's contribution to people: Interdisciplinary pilot study of the Can Gio Mangrove Biosphere Reserve in Viet Nam

    NASA Astrophysics Data System (ADS)

    Cormier-Salem, Marie-Christine; Van Trai, Nguyen; Burgos, Ariadna; Durand, Jean-Dominique; Bettarel, Yvan; Klein, Judith; Duc Huy, Hoang; Panfili, Jacques

    2017-10-01

    The main objective of this pilot study, conducted in June 2015 in the Can Gio Mangrove Biosphere Reserve (Can Gio MBR, Viet Nam), was to develop an interdisciplinary approach to assess some key services provided by reforested mangroves subject to external pressures and varying management policies. We focused on the abundance of viruses, bacteria, endo- and epi- and macrofauna and the diversity of crabs in the mangrove and the exploitation of its resources. The main social finding was that the local inhabitants are aware of the levels of protection of the different zones within the Can Gio MBR and respect them. The core and the buffer zones seem to present a similar ecological status. Genotyping showed a low level of crab diversity although there were many different morphotypes. In the future, we need to understand the stakeholders' general perception of the biodiversity and environment changes by developing an integrated, multi-scale approach.

  4. Cationic and Neutral Cp*M(NO)(κ2-Ph2PCH2CH2PPh2) Complexes of Molybdenum and Tungsten: Lewis-Acid-Induced Intramolecular C-H Activation.

    PubMed

    Handford, Rex C; Wakeham, Russell J; Patrick, Brian O; Legzdins, Peter

    2017-03-20

    Treatment of CH 2 Cl 2 solutions of Cp*M(NO)Cl 2 (Cp* = η 5 -C 5 (CH 3 ) 5 ; M = Mo, W) first with 2 equiv of AgSbF 6 in the presence of PhCN and then with 1 equiv of Ph 2 PCH 2 CH 2 PPh 2 affords the yellow-orange salts [Cp*M(NO)(PhCN)(κ 2 -Ph 2 PCH 2 CH 2 PPh 2 )](SbF 6 ) 2 in good yields (M = Mo, W). Reduction of [Cp*M(NO)(PhCN)(κ 2 -Ph 2 PCH 2 CH 2 PPh 2 )](SbF 6 ) 2 with 2 equiv of Cp 2 Co in C 6 H 6 at 80 °C produces the corresponding 18e neutral compounds, Cp*M(NO)(κ 2 -Ph 2 PCH 2 CH 2 PPh 2 ) which have been isolated as analytically pure orange-red solids. The addition of 1 equiv of the Lewis acid, Sc(OTf) 3 , to solutions of Cp*M(NO)(κ 2 -Ph 2 PCH 2 CH 2 PPh 2 ) at room temperature results in the immediate formation of thermally stable Cp*M(NO→Sc(OTf) 3 )(H)(κ 3 -(C 6 H 4 )PhPCH 2 CH 2 PPh 2 ) complexes in which one of the phenyl substituents of the Ph 2 PCH 2 CH 2 PPh 2 ligands has undergone intramolecular orthometalation. In a similar manner, addition of BF 3 produces the analogous Cp*M(NO→BF 3 )(H)(κ 3 -(C 6 H 4 )PhPCH 2 CH 2 PPh 2 ) complexes. In contrast, B(C 6 F 5 ) 3 forms the 1:1 Lewis acid-base adducts, Cp*M(NO→B(C 6 F 5 ) 3 )(κ 2 -Ph 2 PCH 2 CH 2 PPh 2 ) in CH 2 Cl 2 at room temperature. Upon warming to 80 °C, Cp*Mo(NO→B(C 6 F 5 ) 3 )(κ 2 -Ph 2 PCH 2 CH 2 PPh 2 ) converts cleanly to the orthometalated product Cp*Mo(NO→B(C 6 F 5 ) 3 )(H)(κ 3 -(C 6 H 4 )PhPCH 2 CH 2 PPh 2 ), but Cp*W(NO→B(C 6 F 5 ) 3 )(κ 2 -Ph 2 PCH 2 CH 2 PPh 2 ) generates a mixture of products whose identities remain to be ascertained. Attempts to extend this chemistry to include related Ph 2 PCH 2 PPh 2 compounds have had only limited success. All new complexes have been characterized by conventional spectroscopic and analytical methods, and the solid-state molecular structures of most of them have been established by single-crystal X-ray crystallographic analyses.

  5. Uncovering the CH-53E Doppler Myth

    DTIC Science & Technology

    2008-01-01

    The Corps’ Changing Super Stallion 8 Helicopter Night Vision System 9 Heads-Up Display (BUD) 9 The Infamous Doppler 12 )FUTURE SOLUTIONS 14 Universal...ABSTRACTION FROM, OR REPRODUCTION OF ALL OR ANY PART OF THIS DOCUMENT IS PERMITTED PROVIDED PROPER ACKNOWLEDGEMENT IT MADE. List ofIllustrations Page...remains intimately familiar to those flying the Marine Corps’ CH-53E "Super Stallion " today. Fortunately, the CH.-53Es flown throughout the world today

  6. Collisional excitation of CH2 rotational/fine-structure levels by helium

    NASA Astrophysics Data System (ADS)

    Dagdigian, P. J.; Lique, F.

    2018-02-01

    Accurate determination of the abundance of CH2 in interstellar media relies on both radiative and collisional rate coefficients. We investigate here the rotational/fine-structure excitation of CH2 induced by collisions with He. We employ a recoupling technique to generate fine-structure-resolved cross-sections and rate coefficients from close coupling spin-free scattering calculations. The calculations are based on a recent, high-accuracy CH2-He potential energy surface computed at the coupled clusters level of theory. The collisional cross-section calculations are performed for all fine-structure transitions among the first 22 and 24 energy levels of ortho- and para-CH2, respectively, and for temperatures up to 300 K. As a first application, we simulate the excitation of CH2 in typical molecular clouds. The excitation temperatures of the CH2 lines are found to be small at typical densities of molecular clouds, showing that the non-local thermodynamic equilibrium approach has to be used to analyse interstellar spectra. We also found that the fine-structure lines connected with the 404 - 313 and 505 - 414 rotational transitions show possible maser emissions so that they can be easily seen in emission. These calculations show that CH2 may have to be detected mainly through absorption spectra.

  7. WETTING STIMULATES ATMOSPHERIC CH4 OXIDATION BY ALPINE SOIL (R823442)

    EPA Science Inventory

    Studies were done to assess the effects of soil moisture manipulations on CH4 oxidation in soils from a dry alpine tundra site. When water was added to these soils there was a stimulation of CH4 oxidation. This stimulation of CH4 oxidation took ti...

  8. Above- and belowground fluxes of CH4 from boreal shrubs and Scots pine

    NASA Astrophysics Data System (ADS)

    Halmeenmäki, Elisa; Heinonsalo, Jussi; Santalahti, Minna; Putkinen, Anuliina; Fritze, Hannu; Pihlatie, Mari

    2016-04-01

    Boreal upland forests are considered as an important sink for the greenhouse gas methane (CH4) due to CH4 oxidizing microbes in the soil. However, recent evidence suggests that vegetation can act as a significant source of CH4. Also, preliminary measurements indicate occasional emissions of CH4 above the tree canopies of a boreal forest. Nevertheless, the sources and the mechanisms of the observed CH4 emissions are still mostly unknown. Furthermore, the majority of CH4 flux studies have been conducted with the soil chamber method, thus not considering the role of the vegetation itself. We conducted a laboratory experiment to study separately the above- and belowground CH4 fluxes of bilberry (Vaccinium myrtillus), lingonberry (Vaccinium vitis-idaea), heather (Calluna vulgaris), and Scots pine (Pinus sylvestris), which were grown in microcosms. The above- and belowground fluxes of the plants were measured separately, and these fluxes were compared to fluxes of microcosms containing only humus soil. In addition to the flux measurements, we analysed the CH4 producing archaea (methanogens) and the CH4 consuming bacteria (methanotrophs) with the qPCR method to discover whether these microbes contribute to the CH4 exchange from the plant material and the soil. The results of the flux measurements indicate that the humus soil with roots of lingonberry, heather, and Scots pine consume CH4 compared to bare humus soil. Simultaneously, the shoots of heather and Scots pine emit small amounts of CH4. We did not find detectable amounts of methanogens from any of the samples, suggesting the produced CH4 could be of non-microbial origin, or produced by very small population of methanogens. Based on the first preliminary results, methanotrophs were present in all the studied plant species, and especially in high amounts in the rooted soils, thus implying that the methanotrophs could be responsible of the CH4 uptake in the root-soil systems.

  9. A Time-Dependent Quantum Dynamics Study of the H2 + CH3 yields H + CH4 Reaction

    NASA Technical Reports Server (NTRS)

    Wang, Dunyou; Kwak, Dochan (Technical Monitor)

    2002-01-01

    We present a time-dependent wave-packet propagation calculation for the H2 + CH3 yields H + CH4 reaction in six degrees of freedom and for zero total angular momentum. Initial state selected reaction probability for different initial rotational-vibrational states are presented in this study. The cumulative reaction probability (CRP) is obtained by summing over initial-state-selected reaction probability. The energy-shift approximation to account for the contribution of degrees of freedom missing in the 6D calculation is employed to obtain an approximate full-dimensional CRP. Thermal rate constant is compared with different experiment results.

  10. High Resolution Direct Frequency Comb Spectroscopy of Vinyl Bromide (C_2H_3Br) and Nitromethane (CH_3NO_2) in the CH Stretch Region

    NASA Astrophysics Data System (ADS)

    Changala, Bryan; Spaun, Ben; Patterson, David; Ye, Jun

    2016-06-01

    We present high resolution rovibrational spectra of buffer gas cooled vinyl bromide (C_2H_3Br) and nitromethane (CH_3NO_2) in the 3 μm CH stretch region, acquired via cavity-enhanced direct frequency comb absorption spectroscopy. The ˜10 K translational and rotational temperatures of the molecular gas, as well as the narrow linewidth of the frequency comb, yield well resolved rotational structure, isotope shifts, and nuclear hyperfine splittings. Given the wide bandwidth of the light source and the long path length of the enhancement cavity, we measure entire vibrational bands in a single shot with high signal-to-noise ratios. We discuss spectra of the entire fundamental CH stretch manifolds of both C_2H_3Br and CH_3NO_2, which provide contrasting examples of rovibrational structure of rigid and non-rigid systems. C_2H_3Br is a relatively normal asymmetric top, exhibiting local perturbations to its rotational structure. Conversely, CH_3NO_2 contains an essentially unhindered methyl rotor. Of particular interest are its quasi-degenerate asymmetric CH stretch modes. Here, one must consider multiple couplings between torsional, rotational, and vibrational angular momentum, leading to qualitatively new level patterns and structure.

  11. Selective Generation of the Radical Cation Isomers [CH3CN](•+) and [CH2CNH](•+) via VUV Photoionization of Different Neutral Precursors and Their Reactivity with C2H4.

    PubMed

    Polášek, Miroslav; Zins, Emilie-Laure; Alcaraz, Christian; Žabka, Ján; Křížová, Věra; Giacomozzi, Linda; Tosi, Paolo; Ascenzi, Daniela

    2016-07-14

    Experimental and theoretical studies have been carried out to demonstrate the selective generation of two different C2H3N(+) isomers, namely, the acetonitrile [CH3CN](•+) and the ketenimine [CH2CNH](•+) radical cations. Photoionization and dissociative photoionization experiments from different neutral precursors (acetonitrile and butanenitrile) have been performed using vacuum ultraviolet (VUV) synchrotron radiation in the 10-15 eV energy range, delivered by the DESIRS beamline at the SOLEIL storage ring. For butanenitrile (CH3CH2CH2CN) an experimental ionization threshold of 11.29 ± 0.05 eV is obtained, whereas the appearance energy for the formation of [CH2CNH](•+) fragments is 11.52 ± 0.05 eV. Experimental findings are fully supported by theoretical calculations at the G4 level of theory (ZPVE corrected energies at 0 K), giving a value of 11.33 eV for the adiabatic ionization energy of butanenitrile and an exothermicity of 0.49 for fragmentation into [CH2CNH](•+) plus C2H4, hampered by an energy barrier of 0.29 eV. The energy difference between [CH3CN](•+) and [CH2CNH](•+) is 2.28 eV (with the latter being the lowest energy isomer), and the isomerization barrier is 0.84 eV. Reactive monitoring experiments of the [CH3CN](•+) and [CH2CNH](•+) isomers with C2H4 have been performed using the CERISES guided ion beam tandem mass spectrometer and exploiting the selectivity of ethylene that gives exothermic charge exchange and proton transfer reactions with [CH3CN](•+) but not with [CH2CNH](•+) isomers. In addition, minor reactive channels are observed leading to the formation of new C-C bonds upon reaction of [CH3CN](•+) with C2H4, and their astrochemical implications are briefly discussed.

  12. Interaction of antitumor drug Sn(CH 3) 2Cl 2 with DNA and RNA

    NASA Astrophysics Data System (ADS)

    Nafisi, Shohreh; Sobhanmanesh, Amir; Esm-Hosseini, Majid; Alimoghaddam, Kamran; Tajmir-Riahi, Heidar Ali

    2005-08-01

    Sn(CH3)2Cl2 exerts its antitumor activity in a specific way. Unlike anticancer cis-Pt(NH3)2Cl2 drug which binds strongly to the nitrogen atoms of DNA bases, Sn(CH3)2Cl2 shows no major affinity towards base binding. Thus, the mechanism of action by which tinorganometallic compounds exert antitumor activity would be different from that of the cisplatin drug. The aim of this study was to examine the binding of Sn(CH3)2Cl2 with calf thymus DNA and yeast RNA in aqueous solutions at pH 7.1-6.6 with constant concentrations of DNA and RNA and various molar ratios of Sn(CH3)2Cl2/DNA (phosphate) and Sn(CH3)2Cl2/RNA of 1/40, 1/20, 1/10, 1/5. Fourier transform infrared (FTIR) and UV-visible difference spectroscopic methods were used to determine the Sn(CH3)2Cl2 binding mode, binding constant, sequence selectivity and structural variations of Sn(CH3)2Cl2/DNA and Sn(CH3)2Cl2/RNA complexes in aqueous solution. Sn(CH3)2Cl2 hydrolyzes in water to give Sn(CH3)2(OH)2 and [Sn(CH3)2(OH)(H2O)n]+ species. Spectroscopic evidence showed that interaction occurred mainly through (CH3)2Sn(IV) hydroxide and polynucleotide backbone phosphate group with overall binding constant of K(Sn(CH3)2Cl2-DNA)=1.47×105 M-1 and K(Sn(CH3)2Cl2-RNA)=7.33×105 M-1. Sn(CH3)2Cl2 induced no biopolymer conformational changes with DNA remaining in the B-family structure and RNA in A-conformation upon drug complexation.

  13. Palladium-catalysed electrophilic aromatic C-H fluorination

    NASA Astrophysics Data System (ADS)

    Yamamoto, Kumiko; Li, Jiakun; Garber, Jeffrey A. O.; Rolfes, Julian D.; Boursalian, Gregory B.; Borghs, Jannik C.; Genicot, Christophe; Jacq, Jérôme; van Gastel, Maurice; Neese, Frank; Ritter, Tobias

    2018-02-01

    Aryl fluorides are widely used in the pharmaceutical and agrochemical industries, and recent advances have enabled their synthesis through the conversion of various functional groups. However, there is a lack of general methods for direct aromatic carbon-hydrogen (C-H) fluorination. Conventional methods require the use of either strong fluorinating reagents, which are often unselective and difficult to handle, such as elemental fluorine, or less reactive reagents that attack only the most activated arenes, which reduces the substrate scope. A method for the direct fluorination of aromatic C-H bonds could facilitate access to fluorinated derivatives of functional molecules that would otherwise be difficult to produce. For example, drug candidates with improved properties, such as increased metabolic stability or better blood-brain-barrier penetration, may become available. Here we describe an approach to catalysis and the resulting development of an undirected, palladium-catalysed method for aromatic C-H fluorination using mild electrophilic fluorinating reagents. The reaction involves a mode of catalysis that is unusual in aromatic C-H functionalization because no organometallic intermediate is formed; instead, a reactive transition-metal-fluoride electrophile is generated catalytically for the fluorination of arenes that do not otherwise react with mild fluorinating reagents. The scope and functional-group tolerance of this reaction could provide access to functional fluorinated molecules in pharmaceutical and agrochemical development that would otherwise not be readily accessible.

  14. E2 and SN2 Reactions of X(-) + CH3CH2X (X = F, Cl); an ab Initio and DFT Benchmark Study.

    PubMed

    Bento, A Patrícia; Solà, Miquel; Bickelhaupt, F Matthias

    2008-06-01

    We have computed consistent benchmark potential energy surfaces (PESs) for the anti-E2, syn-E2, and SN2 pathways of X(-) + CH3CH2X with X = F and Cl. This benchmark has been used to evaluate the performance of 31 popular density functionals, covering local-density approximation, generalized gradient approximation (GGA), meta-GGA, and hybrid density-functional theory (DFT). The ab initio benchmark has been obtained by exploring the PESs using a hierarchical series of ab initio methods [up to CCSD(T)] in combination with a hierarchical series of Gaussian-type basis sets (up to aug-cc-pVQZ). Our best CCSD(T) estimates show that the overall barriers for the various pathways increase in the order anti-E2 (X = F) < SN2 (X = F) < SN2 (X = Cl) ∼ syn-E2 (X = F) < anti-E2 (X = Cl) < syn-E2 (X = Cl). Thus, anti-E2 dominates for F(-) + CH3CH2F, and SN2 dominates for Cl(-) + CH3CH2Cl, while syn-E2 is in all cases the least favorable pathway. Best overall agreement with our ab initio benchmark is obtained by representatives from each of the three categories of functionals, GGA, meta-GGA, and hybrid DFT, with mean absolute errors in, for example, central barriers of 4.3 (OPBE), 2.2 (M06-L), and 2.0 kcal/mol (M06), respectively. Importantly, the hybrid functional BHandH and the meta-GGA M06-L yield incorrect trends and qualitative features of the PESs (in particular, an erroneous preference for SN2 over the anti-E2 in the case of F(-) + CH3CH2F) even though they are among the best functionals as measured by their small mean absolute errors of 3.3 and 2.2 kcal/mol in reaction barriers. OLYP and B3LYP have somewhat higher mean absolute errors in central barriers (5.6 and 4.8 kcal/mol, respectively), but the error distribution is somewhat more uniform, and as a consequence, the correct trends are reproduced.

  15. Rhodium-catalyzed C-H functionalization with N-acylsaccharins.

    PubMed

    Wu, Hongxiang; Liu, Tingting; Cui, Ming; Li, Yue; Jian, Junsheng; Wang, Hui; Zeng, Zhuo

    2017-01-18

    A rhodium-catalyzed C-H functionalization with activated amides by decarbonylation has been developed. Notably, this is the first C-H arylation employing N-acylsaccharins as coupling partners to give biaryls in good to excellent yields. The highlight of the work is the high tolerance of functional groups such as formyl, ester, and vinyl and the use of a removable directing group.

  16. Direct production of OH radicals upon CH overtone activation of (CH{sub 3}){sub 2}COO Criegee intermediates

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

    Liu, Fang; Beames, Joseph M.; Lester, Marsha I., E-mail: milester@sas.upenn.edu

    2014-12-21

    Ozonolysis of alkenes, a principle non-photolytic source of atmospheric OH radicals, proceeds through unimolecular decay of energized carbonyl oxide intermediates, known as Criegee intermediates. In this work, cold dimethyl-substituted Criegee intermediates are vibrationally activated in the CH stretch overtone region to drive the 1,4 hydrogen transfer reaction that leads to OH radical products. IR excitation of (CH{sub 3}){sub 2}COO reveals the vibrational states with sufficient oscillator strength, coupling to the reaction coordinate, and energy to surmount the effective barrier (≤ 16.0 kcal mol{sup −1}) to reaction. Insight on the dissociation dynamics is gleaned from homogeneous broadening of the spectral features,more » indicative of rapid intramolecular vibrational energy redistribution and/or reaction, as well as the quantum state distribution of the OH X{sup 2}Π (v = 0) products. The experimental results are compared with complementary electronic structure calculations, which provide the IR absorption spectrum and geometric changes along the intrinsic reaction coordinate. Additional theoretical analysis reveals the vibrational modes and couplings that permit (CH{sub 3}){sub 2}COO to access to the transition state region for reaction. The experimental and theoretical results are compared with an analogous recent study of the IR activation of syn-CH{sub 3}CHOO and its unimolecular decay to OH products [F. Liu, J. M. Beames, A. S. Petit, A. B. McCoy, and M. I. Lester, Science 345, 1596 (2014)].« less

  17. Towards mild metal-catalyzed C-H bond activation.

    PubMed

    Wencel-Delord, Joanna; Dröge, Thomas; Liu, Fan; Glorius, Frank

    2011-09-01

    Functionalizing traditionally inert carbon-hydrogen bonds represents a powerful transformation in organic synthesis, providing new entries to valuable structural motifs and improving the overall synthetic efficiency. C-H bond activation, however, often necessitates harsh reaction conditions that result in functional group incompatibilities and limited substrate scope. An understanding of the reaction mechanism and rational design of experimental conditions have led to significant improvement in both selectivity and applicability. This critical review summarizes and discusses endeavours towards the development of mild C-H activation methods and wishes to trigger more research towards this goal. In addition, we examine select examples in complex natural product synthesis to demonstrate the synthetic utility of mild C-H functionalization (84 references). This journal is © The Royal Society of Chemistry 2011

  18. ChEVAS: Combining Suprarenal EVAS with Chimney Technique

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

    Torella, Francesco, E-mail: f.torella@liverpool.ac.uk; Chan, Tze Y., E-mail: tze.chan@rlbuht.nhs.uk; Shaikh, Usman, E-mail: usman.shaikh@rlbuht.nhs.uk

    2015-10-15

    Endovascular sealing with the Nellix{sup ®} endoprosthesis (EVAS) is a new technique to treat infrarenal abdominal aortic aneurysms. We describe the use of endovascular sealing in conjunction with chimney stents for the renal arteries (chEVAS) in two patients, one with a refractory type Ia endoleak and an expanding aneurysm, and one with a large juxtarenal aneurysm unsuitable for fenestrated endovascular repair (EVAR). Both aneurysms were successfully excluded. Our report confirms the utility of chEVAS in challenging cases, where suprarenal seal is necessary. We suggest that, due to lack of knowledge on its durability, chEVAS should only been considered when moremore » conventional treatment modalities (open repair and fenestrated EVAR) are deemed difficult or unfeasible.« less

  19. Estudio del CH interestelar

    NASA Astrophysics Data System (ADS)

    Olano, C.; Lemarchand, G.; Sanz, A. J.; Bava, J. A.

    El objetivo principal de este proyecto consiste en el estudio de la distribución y abundancia del CH en nubes interestelares a través de la observación de las líneas hiperfinas del CH en 3,3 GHz. El CH es una molécula de amplia distribución en el espacio interestelar y una de las pocas especies que han sido observadas tanto con técnicas de radio como ópticas. Desde el punto de vista tecnológico se ha desarrollado un cabezal de receptor que permitirá la realización de observaciones polarimétricas en la frecuencia de 3,3 GHz, con una temperatura del sistema de 60 K y un ancho de banda de 140 MHz, y que será instalado en el foco primario de la antena parabólica del IAR. El cabezal del receptor es capaz de detectar señales polarizadas, separando las componentes de polarización circular derecha e izquierda. Para tal fin el cabezal consta de dos ramas receptoras que amplificarán la señal y la trasladarán a una frecuencia más baja (frecuencia intermedia), permitiendo de esa forma un mejor transporte de la señal a la sala de control para su posterior procesamiento. El receptor además de tener características polarimétricas, podrá ser usado en el continuo y en la línea, utilizando las ventajas observacionales y de procesamiento de señal que actualmente posee el IAR.

  20. Infrared absorption of CH3OSO and CD3OSO radicals produced upon photolysis of CH3OS(O)Cl and CD3OS(O)Cl in p-H2 matrices.

    PubMed

    Lee, Yu-Fang; Kong, Lin-Jun; Lee, Yuan-Pern

    2012-03-28

    Irradiation at 239 ± 20 nm of a p-H(2) matrix containing methoxysulfinyl chloride, CH(3)OS(O)Cl, at 3.2 K with filtered light from a medium-pressure mercury lamp produced infrared (IR) absorption lines at 3028.4 (attributable to ν(1), CH(2) antisymmetric stretching), 2999.5 (ν(2), CH(3) antisymmetric stretching), 2950.4 (ν(3), CH(3) symmetric stretching), 1465.2 (ν(4), CH(2) scissoring), 1452.0 (ν(5), CH(3) deformation), 1417.8 (ν(6), CH(3) umbrella), 1165.2 (ν(7), CH(3) wagging), 1152.1 (ν(8), S=O stretching mixed with CH(3) rocking), 1147.8 (ν(9), S=O stretching mixed with CH(3) wagging), 989.7 (ν(10), C-O stretching), and 714.5 cm(-1) (ν(11), S-O stretching) modes of syn-CH(3)OSO. When CD(3)OS(O)Cl in a p-H(2) matrix was used, lines at 2275.9 (ν(1)), 2251.9 (ν(2)), 2083.3 (ν(3)), 1070.3 (ν(4)), 1056.0 (ν(5)), 1085.5 (ν(6)), 1159.7 (ν(7)), 920.1 (ν(8)), 889.0 (ν(9)), 976.9 (ν(10)), and 688.9 (ν(11)) cm(-1) appeared and are assigned to syn-CD(3)OSO; the mode numbers correspond to those used for syn-CH(3)OSO. The assignments are based on the photolytic behavior and a comparison of observed vibrational wavenumbers, infrared intensities, and deuterium isotopic shifts with those predicted with the B3P86∕aug-cc-pVTZ method. Our results extend the previously reported four transient IR absorption bands of gaseous syn-CH(3)OSO near 2991, 2956, 1152, and 994 cm(-1) to 11 lines, including those associated with C-O, O-S, and S=O stretching modes. Vibrational wavenumbers of syn-CD(3)OSO are new. These results demonstrate the advantage of a diminished cage effect of solid p-H(2) such that the Cl atom, produced via UV photodissociation of CH(3)OS(O)Cl in situ, might escape from the original cage to yield isolated CH(3)OSO radicals.