WorldWideScience

Sample records for kampong chnang agr

  1. Lessons learnt from and sustainability assessment of Indonesian urban kampong

    Science.gov (United States)

    Surjono, Antariksa; Ridhoni, M.

    2017-06-01

    The search of good (sustainable) model of development has been evolved from the era of City Beautiful to current era of uncertainty. Many urban planner and designers practice western modern concept and design, which are not entirely suitable for developing countries. It has been identified that local forms and characteristics in the urban context have wisdom and content that sustainable for local condition. This paper supports the argument that local characteristics have the qualities of sustainable development by evaluating sustainable development indicators and promoting method in generating aggregate indicator of sustainable development qualities of urban kampong in Indonesia. Fuzzy logic approach, which is widely used in system control design, is promoted in formulating the aggregate indicator of sustainable kampong in Indonesia. The result show that Indonesian kampongs are good in compactness, density, and access. Other indicators will also show sustainable development quality if the lacks are improved.

  2. Relationship between environmental management with quality of kampong space room (Case study: RW 3 of Sukun Sub District, Malang City)

    Science.gov (United States)

    Wardhani, D. K.; Azmi, D. S.; Purnamasari, W. D.

    2017-06-01

    RW 3 Sukun Malang was one of kampong that won the competition kampong environment and had managed to maintain the preservation of the kampong. Society of RW 3 Sukun undertake various activities to manage the environment by optimizing the use of kampong space. Despite RW 3 Sukun had conducted environmental management activities, there are several locations in the kampong space that less well maintained. The purpose of this research was to determine the relation of environmental management with the quality of kampong space in RW 3 Sukun. This research used qualitative and quantitative research approaches. Quantitative research conducted by using descriptive statistical analysis in assessing the quality of kampong space with weighting, scoring, and overlay maps. Quantitative research was also conducted on the relation analysis of environmental management with the quality of kampong space by using typology analysis and pearson correlation analysis. Qualitative research conducted on the analysis of environmental management and the relation analysis of environmental management with the quality of kampong space. Result of this research indicates that environmental management in RW 3 Sukun have relation with the quality of kampong space.

  3. Hydrogeochemistry Characteristics in Kampong Salang, Tioman Island, Pahang, Malaysia

    Science.gov (United States)

    Idris, A. N.; Aris, A. Z.; Praveena, S. M.; Suratman, S.; Tawnie, I.; Samsuddin, M. K. N.; Sefei, A.

    2016-07-01

    The constituents of major ions of groundwater samples has been used to identify the chemical characteristics and the type of groundwater in the low lying area in Kampong Salang located at north-west of Tioman Island in Pahang state. This study aimed to identify the groundwater quality with some geochemical process and to understand groundwater characteristics in the low-lying aquifer of the study area. From that, fourty two (42) groundwater samples were collected and analysed for various parameters. Physical and chemical parameters of groundwater such as pH, electrical conductivity (EC), total dissolved solids (TDS), Ca, Na, Mg, K, HCO3, Cl, SO4, NO3, CO3, were determined. TDS did not exceed 1,000 mg/l with a maximum of 359 mg/l for sampling activities. Generally, groundwater in the study area is fresh, based on the analytical results. Hydrochemical facies of groundwater in the study area are dominated by Ca-HCO3 and Ca-Mg-HCO3 water type. A software known as PHREEQC was used to calculate the saturation indices for the main mineral phases with respect to carbonate and sulphate minerals. Most of the minerals were saturated to undersaturated with respect to carbonate minerals and undersaturated with respect to sulphate minerals composition. Maximum ionic strength in the study area is 0.009 which was found 90 m from the sea. Mostly minerals from calcite and dolomite precipitation are from bedrock of pyroxene hornfel.

  4. Physical and Microbiological Qualities of Kampong-Broiler Crossbred Chickens Meat Raised in Different Stocking Densities

    Directory of Open Access Journals (Sweden)

    C. A. Patria

    2016-12-01

    Full Text Available The crossbreeding between broiler and kampong chickens has been performed to develop a kampong-broiler strain chicken. The chicken stocking condition needs more attention as a part of animal welfare. This study was performed to identify the relationship between the stocking density and the stress based on Temperature Humidity Index (THI and the effect of stocking density on meat quality, i.e., physical, microbiological, and organoleptic. Ninety DOCs of Kampong-Broiler (KB were assigned into a completely randomized design with 3 treatments of stocking density  i.e., 8, 10, and 12 birds m-2. Each treatment was replicated 3 times. The experimental chickens were housed in 9 blocks of housing each with 1 x 1 m2 size. Data on physical and microbiology of meat qualities were analyzed with analysis of variance and continued with Duncan’s multiple range test. The organoleptic data were analyzed by using Kruskal-Wallis test. The result showed that the stocking density did not significantly affect the physical and hedonic quality of KB chicken’s breast. The stocking densities significantly affected (P<0.05 the microbiological variables of breast meat. The average value of THI during maintenance reached 28.98±1.25–29.33±1.32oC. The higher the animal density the higher the THI value that correlated to the stress condition. However, high stocking density did not affect the physical and hedonic quality of breast meat,  thus it can be accepted by the consumers. The higher the stocking density the higher the total plate count, Escherichia coli, and Staphylococcus aureus, without the presence of Salmonella sp. The meat quality of KB chickens raised in the stocking density of 10 birds m-2 meets the requirement of SNI 01-3924-2009.

  5. Sustainable and participatory society for the realization of urban settlement (Case study: Green kampong, Malang City)

    Science.gov (United States)

    Purnamasari, W. D.; Kirana, V.; Wardhani, D. K.

    2017-06-01

    Green Kampong is one of the participatory development to conserve our environment. RW 03 Sukun, Malang City has chosen by researcher become case study because it has be successful to obtain a predicate as “Green Kampong” by following environmental management contests through the participatory society. There was some purpose of this study. The first aim was to find out the level of participation at every kind of the social activities such as waste separation for households, bio-pores project, stone massage therapy on the road, and other greening acts. The second aim was to evaluate the level for sustainable society which consists of: the leadership, the social capital, the internal controls activity, the use of technology, and also the finance of physical development in green kampong. The researcher has used the scoring and schema methods in this study. The result showed that the activity that has reached the maintenance phase are sorting waste and greening, whilst the activity that only reached the stage of control are bio-pores development and stone therapy. The social activities with highest participation was taken by greening act and the lowest was taken by bio-pores project. The sustainability of the community rw 03 Sukun known that of the five components aspects the sustainability of, three of whom were have achieved good progress toward the sustainability of the aspects leadership, social capital, and technology facilities and infrastructure while two aspects of whom were still achieved a good start toward sustainability of the aspects monitoring and evaluation and financing.

  6. Cambodian peasant's contribution to rural development: a perspective from Kampong Thom Province

    Directory of Open Access Journals (Sweden)

    Diepart, JC.

    2010-01-01

    Full Text Available The paper aims to identify the rationality of peasant communities and their contribution to rural development in Kampong Thom province. To do so, an interdisciplinary analytical framework addresses the dynamics of land use and land tenure, the strategies of labor force allocation as well as the determinants of land and labor agricultural productivities amongst peasant communities. It rests on details field surveys in two communes located in very distinct agro-ecological settings of Kampong Thom province. A land use change analysis based on time-series aerial photos is conducted with participatory inventories of natural resources. It shows that endogenous management of forest and fisheries resources generate significant incomes and, at the same time, contribute to maintaining biodiversity. The paper analyses how this contribution is challenged by the non-peasant actors involved in massive State land privatization. Aiming to full employment, peasant households enjoy a great flexibility in the way they allocate labor force, especially in line with the age of active labor and the fluctuation of labor opportunity costs. Principally due to an unequal land holding distribution, agricultural income is unfairly distributed but this inequality is actually balanced by the access to common-pool resources of crucial importance for the poorest and by the recourse to non farming activities, which is an important factor of socio-economic differentiation amongst households. The main economic indicators of rice production confirm that peasant households always try to maximize their income in step with the production factor they have in relatively less amount. A land market simulation stresses that, contrarily to theoretical assumptions, land access through sale (and purchase does not result in a fairer land distribution. Nevertheless, land leases amongst peasant households seem more promising to ensure equitable access to land as they are embedded in collective

  7. FEEDING EFFECT OF INULIN DERIVED FROM DAHLIA TUBER COMBINED WITH Lactobacillus sp. ON MEAT PROTEIN MASS OF CROSSBRED KAMPONG CHICKEN

    Directory of Open Access Journals (Sweden)

    Z. H. Abdurrahman

    2016-03-01

    Full Text Available The objective of the study was to determine the effects of feeding Lactobacillus species (Lactobacillus sp. and inulin derived from dahlia tuber powder on antioxidant activity, calcium mass, and protein mass of crossbred kampong chicken meat. A total of  168 birds of 21 days old crossbred kampong chickens were randomly allocated into 6 treatments with four replications per treatment. The present experiment was assigned in  a completely randomized design with 2 x 3 factorial scheme. The first factor was levels of dahlia tuber powder, namely 0.8% (A1 and 1.2% (A2, and the second factor was levels of Lactobacillus sp., namely none (B0, 1.2 mL (108 cfu/mL/B1 and 2.4 mL (108 cfu/mL/B2. The parameters measured were antioxidant activity, meat calcium and protein mass. Data were subjected to analysis of variance and followed by Duncan multiple range test (P<0.05 when the treatment indicated significant effect. The supplementation of dahlia tuber powder and Lactobacillus sp. significantly (P<0.05 increased antioxidant activity and protein mass of meat. However, calcium mass of meat was not significantly affected by treatments. In conclusion, feeding dahlia tuber powder at the level of 1.2% combined with Lactobacillus sp. at 1.2 mL (108 cfu/mL, can be categorized as the best combination based on the increase in antioxidant activity and meat protein mass.  

  8. AGR-1 Thermocouple Data Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jeff Einerson

    2012-05-01

    This report documents an effort to analyze measured and simulated data obtained in the Advanced Gas Reactor (AGR) fuel irradiation test program conducted in the INL's Advanced Test Reactor (ATR) to support the Next Generation Nuclear Plant (NGNP) R&D program. The work follows up on a previous study (Pham and Einerson, 2010), in which statistical analysis methods were applied for AGR-1 thermocouple data qualification. The present work exercises the idea that, while recognizing uncertainties inherent in physics and thermal simulations of the AGR-1 test, results of the numerical simulations can be used in combination with the statistical analysis methods to further improve qualification of measured data. Additionally, the combined analysis of measured and simulation data can generate insights about simulation model uncertainty that can be useful for model improvement. This report also describes an experimental control procedure to maintain fuel target temperature in the future AGR tests using regression relationships that include simulation results. The report is organized into four chapters. Chapter 1 introduces the AGR Fuel Development and Qualification program, AGR-1 test configuration and test procedure, overview of AGR-1 measured data, and overview of physics and thermal simulation, including modeling assumptions and uncertainties. A brief summary of statistical analysis methods developed in (Pham and Einerson 2010) for AGR-1 measured data qualification within NGNP Data Management and Analysis System (NDMAS) is also included for completeness. Chapters 2-3 describe and discuss cases, in which the combined use of experimental and simulation data is realized. A set of issues associated with measurement and modeling uncertainties resulted from the combined analysis are identified. This includes demonstration that such a combined analysis led to important insights for reducing uncertainty in presentation of AGR-1 measured data (Chapter 2) and interpretation of

  9. Effects of logging and recruitment on community phylogenetic structure in 32 permanent forest plots of Kampong Thom, Cambodia.

    Science.gov (United States)

    Toyama, Hironori; Kajisa, Tsuyoshi; Tagane, Shuichiro; Mase, Keiko; Chhang, Phourin; Samreth, Vanna; Ma, Vuthy; Sokh, Heng; Ichihashi, Ryuji; Onoda, Yusuke; Mizoue, Nobuya; Yahara, Tetsukazu

    2015-02-19

    Ecological communities including tropical rainforest are rapidly changing under various disturbances caused by increasing human activities. Recently in Cambodia, illegal logging and clear-felling for agriculture have been increasing. Here, we study the effects of logging, mortality and recruitment of plot trees on phylogenetic community structure in 32 plots in Kampong Thom, Cambodia. Each plot was 0.25 ha; 28 plots were established in primary evergreen forests and four were established in secondary dry deciduous forests. Measurements were made in 1998, 2000, 2004 and 2010, and logging, recruitment and mortality of each tree were recorded. We estimated phylogeny using rbcL and matK gene sequences and quantified phylogenetic α and β diversity. Within communities, logging decreased phylogenetic diversity, and increased overall phylogenetic clustering and terminal phylogenetic evenness. Between communities, logging increased phylogenetic similarity between evergreen and deciduous plots. On the other hand, recruitment had opposite effects both within and between communities. The observed patterns can be explained by environmental homogenization under logging. Logging is biased to particular species and larger diameter at breast height, and forest patrol has been effective in decreasing logging.

  10. AGR-1, AGR-2 and AGR-3/4 Dimensional Change Data Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Herberger, Sarah E. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-02-01

    A series of Advanced Gas Reactor (AGR) experiments have been completed in the Advanced Test Reactor at Idaho National Laboratory in support of qualification and development of tristructural isotropic fuel. Each AGR test consists of multiple independently controlled and monitored capsules containing fuel compacts placed in a graphite cylinder. These capsules are instrumented with thermocouples embedded in the graphite, enabling temperature control. The fuel compacts are composed of fuel particles surrounded by a graphitic A3 matrix material. Dimensional change in AGR fuel compacts is vital because the swelling or shrinkage affects the size of the gas gaps that are used to control temperatures. Analysis of dimensional change in the AGR fuel compacts is needed to establish the variables directly relating to compact shrinkage. The variables initially identified for consideration were matrix density, compact density, fuel packing fraction, uranium loading, fuel particle diameter, cumulative fast neutron fluence, and volume average time average fuel temperature. In addition to the data available from the AGR experiments, the analysis included specimens formed from the same A3 matrix material used in Advanced Graphite Creep (AGC) experiments, which provide graphite creep data during irradiation for design and licensing purposes. The primary purpose of including the AGC specimens was to encompass dimensional behavior at zero packing fraction, zero uranium loading, and zero particle diameter. All possible combinations of first-order variable regressions were considered in the analysis. The study focused on identifying the best regression models for percent change in diameter, length, and volume. Bootstrap analysis was used to ensure the resulting regression models were robust and well-performing. The variables identified as very significant in predicting change in one or more dimensions (diameter, length, and volume) are volume average time average temperature, fast fluence

  11. AGR-1 Data Qualification Report

    Energy Technology Data Exchange (ETDEWEB)

    Michael Abbott

    2010-03-01

    ABSTRACT Projects for the very high temperature reactor (VHTR) Technology Development Office (TDO) program provide data in support of Nuclear Regulatory Commission licensing of the VHTR. Fuel and materials to be used in the reactor are tested and characterized to quantify performance in high temperature and high fluence environments. The VHTR program has established the NGNP Data Management and Analysis System (NDMAS) to ensure that VHTR data are (1) qualified for use, (2) stored in a readily accessible electronic form, and (3) analyzed to extract useful results. This document focuses on the first NDMAS objective. It describes the data streams associated with the first Advanced Gas Reactor experiment (AGR-1), the processing of these data within NDMAS, and reports the qualification status of the data. Data qualification activities within NDMAS for specific types of data are determined by the data qualification category assigned by the data generator. They include: (1) capture testing, to confirm that the data stored within NDMAS are identical to the raw data supplied, (2) accuracy testing, to confirm that the data are an accurate representation of the system or object being measured, and (3) documentation that the data were collected under an NQA-1 or equivalent quality assurance program. The NDMAS database processing and qualification status of the following five data streams is reported in this document: 1. Fuel fabrication data. All data have been processed into the NDMAS database and qualified (1,819 records). 2. Fuel irradiation data. Data from all 13 AGR-1 reactor cycles have been processed into the NDMAS database and tested. Of these, 85% have been qualified and 15% have failed NDMAS accuracy testing. 3. FPMS data. Reprocessed (January 2010) data from all 13 AGR-1 reactor cycles have been processed into the database and capture tested. Final qualification of these data will be recorded after QA approval of an Engineering Calculations and Analysis Report

  12. ecotecnia agrícola

    Directory of Open Access Journals (Sweden)

    S. Orozco Cirilo

    2008-01-01

    Full Text Available Las Escuelas de Campo (EC son un método de extensión participativo que permite desarrollar capacidades analíticas, pensamiento crítico y, creatividad. La investigación se realizó en la región Mazateca de Oaxaca, la cual se caracteriza por su alto rezago tecnológico, porque resulta de relevancia científica, social y ecológica conocer, en este contexto, los alcances de metodologías alternativas de extensionismo sobre la adopción de ecotecniasagrícolas. Nuestro objetivo fue conocer la influencia del conocimiento otorgado en EC sobre el índice de adopción final de ecotecnia generada localmente, como alternativa a la enorme dependencia tecnológica. Las variables analizadas fueron: índice de adopción inicial, nivel inicial de conocimientos, número de cursos otorgados en EC, índice de adopción final y, nivel final de conocimientos. A una muestra de dos estratos participantes y un grupo testigo, fueron aplicados 135 cuestionarios. Para probar nuestras hipótesis los resultados de éstos se sometieron al análisis de varianza y correlación. Encontramos que solamente el índice de adopción final obtenido por los participantes experimentó incrementos estadísticamente significativos respecto a la condición inicial, debido a su participación en EC y al consecuente aumento en el conocimiento de la ecotecnia. Esto implica que la metodología propuesta incrementa la adopción de ecotecnias generadas localmente, consolidándose como un paradigmaalternativo en extensión agrícola.

  13. Power plant performance - resurrection of the AGR

    Energy Technology Data Exchange (ETDEWEB)

    Kovan, Dick

    1994-04-01

    When the rest of the electricity supply industry was privatized in 1990, Nuclear Electric became responsible for the running of nuclear plants in England and Wales. These included five AGR stations, the output and revenue from which have increased dramatically. The absence of a fully representative prototype reactor led to deficiencies in the design and problems in the construction and commissioning of the AGR stations, particularly the first, Dungeness B. Subsequent plant and design improvements have led to the achievement of good performance, however, and Nuclear Electric's better understanding of AGR safety has been translated into higher output because it has been possible to run nearer to the limits on power ratings, temperatures and pressures. Increased efficiency in refuelling and greater productivity of boilers, gas circulators and turbines, together with improved servicing and maintenance procedures have all contributed to a reduction in reactor downtime. These and other actions which have been employed by Nuclear Electric to turn round the fortunes of the AGR stations are discussed. (UK).

  14. Nave agrícola – Brasil

    Directory of Open Access Journals (Sweden)

    Levi, Rino

    1959-07-01

    Full Text Available Recientemente se ha realizado el proyecto de ejecución de una amplia nave dedicada a garaje, aparcamiento y conservación de maquinaria móvil agrícola en San José Dos Campos (Brasil.

  15. AGR-2 and AGR-3/4 Release-to-Birth Ratio Data Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Pham, Binh T. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Very High Temperature Reactor Technology Development Office; Einerson, Jeffrey J. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Very High Temperature Reactor Technology Development Office; Scates, Dawn M. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Very High Temperature Reactor Technology Development Office; Maki, John T. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Very High Temperature Reactor Technology Development Office; Petti, David A. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Very High Temperature Reactor Technology Development Office

    2014-09-01

    A series of Advanced Gas Reactor (AGR) irradiation tests is being conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) in support of development and qualification of tristructural isotropic (TRISO) low enriched fuel used in the High Temperature Gas-cooled Reactor (HTGR). Each AGR test consists of multiple independently controlled and monitored capsules containing fuel compacts placed in a graphite cylinder shrouded by a steel shell. These capsules are instrumented with thermocouples embedded in the graphite enabling temperature control. AGR configuration and irradiation conditions are based on prismatic HTGR technology that is distinguished primarily through use of helium coolant, a low-power-density ceramic core capable of withstanding very high temperatures, and TRISO coated particle fuel. Thus, these tests provide valuable irradiation performance data to support fuel process development, qualify fuel for normal operating conditions, and support development and validation of fuel performance and fission product transport models and codes.

  16. Gambaran Biokimia dan Leukosit Darah Ayam Kampung Umur 25 Hari yang Diberi Probiotik Fungi Rhizopus oryzae (BIOCHEMICAL AND BLOOD LEUKOCYTES DESCRIPTIONS OF 25 DAYS AGE OF KAMPONG CHICKEN FEEDWITH FUNGI Rhizopusoryzae

    Directory of Open Access Journals (Sweden)

    Isroli Isroli

    2017-04-01

    Full Text Available The aim of this present study was to investigate the effect of dietary supplementation of fungusprobiotic Rhizopus oryzae on the serum biochemical and leukocytes profile of 25 days old Kampong chicken.A total of 100 day-old chicks weight 39.65 ± 1.46 g were randomly allotted into 20 plots of enclosure. Allchickens received feed containing 20.54% crude protein, metabolism energi of 2913 kcal/kg ad libitum.Acompletely randomized experimental design with 4 treatments and five replicates, each replicate of 5chicken was applied. The treatments were: supplementation of fungus probiotic R.oryzae in thediets (atthe levels of 0% (T0, 0.2% (T1, 0.4% (T2 and 0.6% (T3, respectively. The treatment diets were givenatdays 1, 7, 14 and 21, respectively. Parameters measured includingblood biochemistry (uric acid, totalprotein, albumin and globulin and leukocyte profile (total leukocytes and its differentials. Results showedthat dietary supplementation of probiotics R. oryzae had no effect on the parameters observed, except forthe percentage of eosinophils. It can be concluded that the administration of R. oryzae in the ration ateveryseven days intervals failed to improve the physiological condition of the Kampong chickens.

  17. AGR-1 Data Qualification Interim Report

    Energy Technology Data Exchange (ETDEWEB)

    Machael Abbott

    2009-08-01

    Projects for the very-high-temperature reactor (VHTR) program provide data in support of Nuclear Regulatory Commission licensing of the VHTR. Fuel and materials to be used in the reactor are tested and characterized to quantify performance in high temperature and high fluence environments. The VHTR Program has established the NGNP Data Management and Analysis System (NDMAS) to ensure that VHTR data are (1) qualified for use, (2) stored in a readily accessible electronic form, and (3) analyzed to extract useful results. This document focuses on the first NDMAS objective. It describes the data streams associated with the first Advanced Gas Reactor (AGR-1) experiment, the processing of these data within NDMAS, and reports the interim FY09 qualification status of the AGR-1 data to date. Data qualification activities within NDMAS for specific types of data are determined by the data qualification category, which is assigned by the data generator, and include: (1) capture testing, to confirm that the data stored within NDMAS are identical to the raw data supplied, (2) accuracy testing, to confirm that the data are an accurate representation of the system or object being measured, and (3) documentation that the data were collected under an NQA-1 or equivalent QA program. The interim qualification status of the following four data streams is reported in this document: (1) fuel fabrication data, (2) fuel irradiation data, (3) fission product monitoring system (FPMS) data, and (4) Advanced Test Reactor (ATR) operating conditions data. A final report giving the NDMAS qualification status of all AGR-1 data (including cycle 145A) is planned for February 2010.

  18. AGR-1 Post Irradiation Examination Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Demkowicz, Paul Andrew [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-08-01

    The post-irradiation examination (PIE) of the Advanced Gas Reactor (AGR)-1 experiment was a multi-year, collaborative effort between Idaho National Laboratory (INL) and Oak Ridge National Laboratory (ORNL) to study the performance of UCO (uranium carbide, uranium oxide) tristructural isotropic (TRISO) coated particle fuel fabricated in the U.S. and irradiated at the Advanced Test Reactor at INL to a peak burnup of 19.6% fissions per initial metal atom. This work involved a broad array of experiments and analyses to evaluate the level of fission product retention by the fuel particles and compacts (both during irradiation and during post-irradiation heating tests to simulate reactor accident conditions), investigate the kernel and coating layer morphology evolution and the causes of coating failure, and explore the migration of fission products through the coating layers. The results have generally confirmed the excellent performance of the AGR-1 fuel, first indicated during the irradiation by the observation of zero TRISO coated particle failures out of 298,000 particles in the experiment. Overall release of fission products was determined by PIE to have been relatively low during the irradiation. A significant finding was the extremely low levels of cesium released through intact coatings. This was true both during the irradiation and during post-irradiation heating tests to temperatures as high as 1800°C. Post-irradiation safety test fuel performance was generally excellent. Silver release from the particles and compacts during irradiation was often very high. Extensive microanalysis of fuel particles was performed after irradiation and after high-temperature safety testing. The results of particle microanalysis indicate that the UCO fuel is effective at controlling the oxygen partial pressure within the particle and limiting kernel migration. Post-irradiation examination has provided the final body of data that speaks to the quality of the AGR-1 fuel, building

  19. AGR-1 Safety Test Predictions using the PARFUME code

    Energy Technology Data Exchange (ETDEWEB)

    Blaise Collin

    2012-05-01

    The PARFUME modeling code was used to predict failure probability of TRISO-coated fuel particles and diffusion of fission products through these particles during safety tests following the first irradiation test of the Advanced Gas Reactor program (AGR-1). These calculations support the AGR-1 Safety Testing Experiment, which is part of the PIE effort on AGR-1. Modeling of the AGR-1 Safety Test Predictions includes a 620-day irradiation followed by a 300-hour heat-up phase of selected AGR-1 compacts. Results include fuel failure probability, palladium penetration, and fractional release of fission products. Results show that no particle failure is predicted during irradiation or heat-up, and that fractional release of fission products is limited during irradiation but that it significantly increases during heat-up.

  20. Uncertainty Quantification of Calculated Temperatures for the AGR-1 Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Binh T. Pham; Jeffrey J. Einerson; Grant L. Hawkes

    2012-04-01

    This report documents an effort to quantify the uncertainty of the calculated temperature data for the first Advanced Gas Reactor (AGR-1) fuel irradiation experiment conducted in the INL's Advanced Test Reactor (ATR) in support of the Next Generation Nuclear Plant (NGNP) R&D program. Recognizing uncertainties inherent in physics and thermal simulations of the AGR-1 test, the results of the numerical simulations can be used in combination with the statistical analysis methods to improve qualification of measured data. Additionally, the temperature simulation data for AGR tests can be used for validation of the fuel transport and fuel performance simulation models. The crucial roles of the calculated fuel temperatures in ensuring achievement of the AGR experimental program objectives require accurate determination of the model temperature uncertainties. The report is organized into three chapters. Chapter 1 introduces the AGR Fuel Development and Qualification program and provides overviews of AGR-1 measured data, AGR-1 test configuration and test procedure, and thermal simulation. Chapters 2 describes the uncertainty quantification procedure for temperature simulation data of the AGR-1 experiment, namely, (i) identify and quantify uncertainty sources; (ii) perform sensitivity analysis for several thermal test conditions; (iii) use uncertainty propagation to quantify overall response temperature uncertainty. A set of issues associated with modeling uncertainties resulting from the expert assessments are identified. This also includes the experimental design to estimate the main effects and interactions of the important thermal model parameters. Chapter 3 presents the overall uncertainty results for the six AGR-1 capsules. This includes uncertainties for the daily volume-average and peak fuel temperatures, daily average temperatures at TC locations, and time-average volume-average and time-average peak fuel temperatures.

  1. Uncertainty Quantification of Calculated Temperatures for the AGR-1 Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Binh T. Pham; Jeffrey J. Einerson; Grant L. Hawkes

    2013-03-01

    This report documents an effort to quantify the uncertainty of the calculated temperature data for the first Advanced Gas Reactor (AGR-1) fuel irradiation experiment conducted in the INL’s Advanced Test Reactor (ATR) in support of the Next Generation Nuclear Plant (NGNP) R&D program. Recognizing uncertainties inherent in physics and thermal simulations of the AGR-1 test, the results of the numerical simulations can be used in combination with the statistical analysis methods to improve qualification of measured data. Additionally, the temperature simulation data for AGR tests can be used for validation of the fuel transport and fuel performance simulation models. The crucial roles of the calculated fuel temperatures in ensuring achievement of the AGR experimental program objectives require accurate determination of the model temperature uncertainties. The report is organized into three chapters. Chapter 1 introduces the AGR Fuel Development and Qualification program and provides overviews of AGR-1 measured data, AGR-1 test configuration and test procedure, and thermal simulation. Chapters 2 describes the uncertainty quantification procedure for temperature simulation data of the AGR-1 experiment, namely, (i) identify and quantify uncertainty sources; (ii) perform sensitivity analysis for several thermal test conditions; (iii) use uncertainty propagation to quantify overall response temperature uncertainty. A set of issues associated with modeling uncertainties resulting from the expert assessments are identified. This also includes the experimental design to estimate the main effects and interactions of the important thermal model parameters. Chapter 3 presents the overall uncertainty results for the six AGR-1 capsules. This includes uncertainties for the daily volume-average and peak fuel temperatures, daily average temperatures at TC locations, and time-average volume-average and time-average peak fuel temperatures.

  2. Cloning of an agr homologue of Staphylococcus saprophyticus.

    Science.gov (United States)

    Sakinc, Türkan; Kulczak, Pawel; Henne, Karsten; Gatermann, Sören G

    2004-08-01

    An agr homologue of Staphylococcus saprophyticus was identified, cloned and sequenced. The gene locus shows homologies to other staphylococcal agr systems, especially to those of S. epidermidis and S. lugdunensis. A putative RNAIII was identified and found to be differentially expressed during the growth phases. In contrast to the RNAIII molecules of S. epidermidis and S. aureus it does not contain an open reading frame that codes for a protein with homologies to the delta-toxin. Using PCR, the agr was found to be present in clinical isolates of S. saprophyticus.

  3. Zoning Districts, ag-res, Published in 2008, Duchesne County.

    Data.gov (United States)

    NSGIC GIS Inventory (aka Ramona) — This Zoning Districts dataset, was produced all or in part from Other information as of 2008. It is described as 'ag-res'. Data by this publisher are often provided...

  4. Safety Testing of AGR-2 UCO Compacts 6-4-2 and 2-3-1

    Energy Technology Data Exchange (ETDEWEB)

    Hunn, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Morris, Robert N. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Baldwin, Charles A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Burns, Zachary M. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Montgomery, Fred C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Skitt, Darren J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-08-01

    Post-irradiation examination (PIE) and elevated-temperature safety testing are being performed on tristructural-isotropic (TRISO) coated-particle fuel compacts from the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program second irradiation experiment (AGR-2). Details on this irradiation experiment have been previously reported [Collin 2014]. The AGR-2 PIE effort builds upon the understanding acquired throughout the AGR-1 PIE campaign [Demkowicz et al. 2015] and is establishing a database for the different AGR-2 fuel designs.

  5. Creating kampong as tourist attractions

    Science.gov (United States)

    Sari, N.; Utama, R.; Hidayat, A. R. T.; Zamrony, A. B.

    2017-06-01

    Tourism attractions become one of the main components and they drive the tourism activity in a region. The quality of tourism attractions would affect tourists’ visits. Tourism power can basically be built on any conditions which can attract people to visit. Towns is full of activities which include their economic, social, cultural and physical features, if they are presented properly, they can be a tourist attraction. Kampung City, as a form of urban settlement, has the potential to be developed as a tourism attraction. Kampung is not only a physical area of housing but it has also productive activities. Even the city’s economic activities are also influenced by the productive activities of its Kampung. The shape of Kampung which varies in physical, social, economic and cultural raises special characteristics of each Kampung. When it is linked with the city’s tourism activities, these special characteristics of course could be one of the attractions to attract tourists. This paper studies about one of Kampung in the Malang City. Administratively located in the Penanggungan Village Lowokwaru District, but the potential will just be focused on RW 4. Main productive activities of this village are pottery. In contrast to ceramics, pottery is made from clay and its uniqueness in color and shape. Based on the history of pottery in the Malang, it is concentrated in Penanggungan Village. But along with its development, pottery is decreasingly in demand and number of craftsmen is dwindling. Based on these circumstances, a concept is prepared to raise the image of the region as the Kampung of pottery and to repack it as a tourism attraction of the city.

  6. An agr quorum sensing system that regulates granulose formation and sporulation in Clostridium acetobutylicum.

    Science.gov (United States)

    Steiner, Elisabeth; Scott, Jamie; Minton, Nigel P; Winzer, Klaus

    2012-02-01

    The Gram-positive, anaerobic, endospore-forming bacterium Clostridium acetobutylicum has considerable biotechnological potential due to its ability to produce solvents as fermentation products, in particular the biofuel butanol. Its genome contains a putative agr locus, agrBDCA, known in staphylococci to constitute a cyclic peptide-based quorum sensing system. In staphylococci, agrBD is required for the generation of a peptide signal that, upon extracellular accumulation, is sensed by an agrCA-encoded two-component system. Using ClosTron technology, agrB, agrC, and agrA mutants of C. acetobutylicum ATCC 824 were generated and phenotypically characterized. Mutants and wild type displayed similar growth kinetics and no apparent differences in solvent formation under the conditions tested. However, the number of heat-resistant endospores formed by the mutants in liquid culture was reduced by about one order of magnitude. On agar-solidified medium, spore formation was more strongly affected, particularly in agrA and agrC mutants. Similarly, accumulation of the starch-like storage compound granulose was almost undetectable in colonies of agrB, agrA, and agrC mutants. Importantly, these defects could be genetically complemented, demonstrating that they were directly linked to agr inactivation. A diffusible factor produced by agrBD-expressing strains was found to restore granulose and spore formation in the agrB mutant. Furthermore, a synthetic cyclic peptide, designed on the basis of the C. acetobutylicum AgrD sequence, was also capable of complementing the defects of the agrB mutant when added exogenously to the culture. Together, these findings support the hypothesis that agr-dependent quorum sensing is involved in the regulation of sporulation and granulose formation in C. acetobutylicum.

  7. An agr Quorum Sensing System That Regulates Granulose Formation and Sporulation in Clostridium acetobutylicum

    Science.gov (United States)

    Steiner, Elisabeth; Scott, Jamie

    2012-01-01

    The Gram-positive, anaerobic, endospore-forming bacterium Clostridium acetobutylicum has considerable biotechnological potential due to its ability to produce solvents as fermentation products, in particular the biofuel butanol. Its genome contains a putative agr locus, agrBDCA, known in staphylococci to constitute a cyclic peptide-based quorum sensing system. In staphylococci, agrBD is required for the generation of a peptide signal that, upon extracellular accumulation, is sensed by an agrCA-encoded two-component system. Using ClosTron technology, agrB, agrC, and agrA mutants of C. acetobutylicum ATCC 824 were generated and phenotypically characterized. Mutants and wild type displayed similar growth kinetics and no apparent differences in solvent formation under the conditions tested. However, the number of heat-resistant endospores formed by the mutants in liquid culture was reduced by about one order of magnitude. On agar-solidified medium, spore formation was more strongly affected, particularly in agrA and agrC mutants. Similarly, accumulation of the starch-like storage compound granulose was almost undetectable in colonies of agrB, agrA, and agrC mutants. Importantly, these defects could be genetically complemented, demonstrating that they were directly linked to agr inactivation. A diffusible factor produced by agrBD-expressing strains was found to restore granulose and spore formation in the agrB mutant. Furthermore, a synthetic cyclic peptide, designed on the basis of the C. acetobutylicum AgrD sequence, was also capable of complementing the defects of the agrB mutant when added exogenously to the culture. Together, these findings support the hypothesis that agr-dependent quorum sensing is involved in the regulation of sporulation and granulose formation in C. acetobutylicum. PMID:22179241

  8. AGR-2 Data Qualification Report for ATR Cycle 154B

    Energy Technology Data Exchange (ETDEWEB)

    Binh Pham; Jeff Einerson

    2014-01-01

    This report provides the data qualification status of Advanced Gas Reactor-2 (AGR-2) fuel irradiation experimental data from Advanced Test Reactor (ATR) Cycle 154B as recorded in the Nuclear Data Management and Analysis System (NDMAS). This is the last cycle of AGR-2 irradiation, as the test train was pulled from the ATR core during the outage portion of ATR Cycle 155A. The AGR-2 data streams addressed in this report include thermocouple (TC) temperatures, sweep gas data (flow rates including new Fission Product Monitoring (FPM) downstream flows from Fission Product Monitoring System (FPMS) detectors, pressure, and moisture content), and FPMS data (release rates and release-to-birth rate ratios [R/Bs]) for each of the six capsules in the AGR-2 experiment. The final data qualification status for these data streams is determined by a Data Review Committee (DRC) comprised of AGR technical leads, Sitewide Quality Assurance (QA), and NDMAS analysts. The Data Review Committee reviewed the data acquisition process, considered whether the data met the requirements for data collection as specified in QA-approved Very High Temperature Reactor (VHTR) data collection plans, examined the results of NDMAS data testing and statistical analyses, and confirmed the qualification status of the data as given in this report.

  9. Trabajadores agrícolas y subjetividad en California

    OpenAIRE

    Florencio Posadas Segura

    2014-01-01

    En este trabajo se explora el problema de la subjetividad de los trabajadores agríco - las, partiendo de la hipótesis de que éstos consideran malas sus condiciones de vida y de trabajo. Mediante el trabajo de campo se demostraron sus conocimientos y opi - niones sobre su situación laboral y existencial en el Valle de San Joaquín California durante 2007 y 2008. Se descubrió que la visión del trabajador agrícola está basada en la subjetivación y reinterpretación de sus circunstancias objetivas ...

  10. La maquinaria agrícola en el siglo XX

    OpenAIRE

    Ruiz-Altisent, Margarita; Gil Sierra, Jacinto

    2000-01-01

    La evolución de la maquinaria agrícola en el siglo XX ha sido tan espectacular que, de los tres grandes avances habidos a lo largo de la historia de la maquinaria agrícola, dos de ellos podemos considerar que marcan el comienzo y el fin del siglo XX. El primer avance fundamental se dio el día en que el hombre que removía la tierra golpeándola con una herramienta tipo azada decidió avanzar con ella introducida en el suelo venciendo la fuerza de tiro. Nació así el arado en un tiempo indetermina...

  11. El Ingeniero Agrícola en la Agroindustria

    Directory of Open Access Journals (Sweden)

    Ramos Sarria Ramiro

    1985-12-01

    Full Text Available En este artículo se da a conocer la capacidad técnica y administrativa que posee el Ingeniero Agrícola, para organizar un sistema coherente que logre definir, planificar y promover una política de desarrollo científico y tecnológico en la agroindustria.

  12. AGR-2 Irradiation Test Final As-Run Report

    Energy Technology Data Exchange (ETDEWEB)

    Collin, Blaise P. [Idaho National Lab. (INL), Idaho Falls, ID (United States). VHTR Program

    2014-08-01

    This document presents the as-run analysis of the AGR-2 irradiation experiment. AGR-2 is the second of the planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the U.S. Department of Energy as part of the Very High Temperature Reactor (VHTR) Technical Development Office (TDO) program. The objectives of the AGR-2 experiment are to: (a) Irradiate UCO (uranium oxycarbide) and UO2 (uranium dioxide) fuel produced in a large coater. Fuel attributes are based on results obtained from the AGR-1 test and other project activities. (b) Provide irradiated fuel samples for post-irradiation experiment (PIE) and safety testing. (c) Support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. The primary objective of the test was to irradiate both UCO and UO2 TRISO (tri-structural isotropic) fuel produced from prototypic scale equipment to obtain normal operation and accident condition fuel performance data. The UCO compacts were subjected to a range of burnups and temperatures typical of anticipated prismatic reactor service conditions in three capsules. The test train also includes compacts containing UO2 particles produced independently by the United States, South Africa, and France in three separate capsules. The range of burnups and temperatures in these capsules were typical of anticipated pebble bed reactor service conditions. The results discussed in this report pertain only to U.S. produced fuel.

  13. AGR-2 Irradiation Test Final As-Run Report

    Energy Technology Data Exchange (ETDEWEB)

    Collin, Blaise P. [Idaho National Lab. (INL), Idaho Falls, ID (United States). VHTR Program

    2014-08-01

    This document presents the as-run analysis of the AGR-2 irradiation experiment. AGR-2 is the second of the planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the U.S. Department of Energy as part of the Very High Temperature Reactor (VHTR) Technology Development Office (TDO) program. The objectives of the AGR-2 experiment are to: 1. Irradiate UCO (uranium oxycarbide) and UO2 (uranium dioxide) fuel produced in a large coater. Fuel attributes are based on results obtained from the AGR-1 test and other project activities. 2. Provide irradiated fuel samples for post-irradiation experiment (PIE) and safety testing. 3. Support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. The primary objective of the test was to irradiate both UCO and UO2 TRISO (tristructural isotropic) fuel produced from prototypic scale equipment to obtain normal operation and accident condition fuel performance data. The UCO compacts were subjected to a range of burnups and temperatures typical of anticipated prismatic reactor service conditions in three capsules. The test train also includes compacts containing UO2 particles produced independently by the United States, South Africa, and France in three separate capsules. The range of burnups and temperatures in these capsules were typical of anticipated pebble bed reactor service conditions. The results discussed in this report pertain only to U.S.-produced fuel.

  14. Differential expression of anterior gradient gene AGR2 in prostate cancer

    Directory of Open Access Journals (Sweden)

    Knutzen Laura A

    2010-12-01

    Full Text Available Abstract Background The protein AGR2 is a putative member of the protein disulfide isomerase family and was first identified as a homolog of the Xenopus laevis gene XAG-2. AGR2 has been implicated in a number of human cancers. In particular, AGR2 has previously been found to be one of several genes that encode secreted proteins showing increased expression in prostate cancer cells compared to normal prostatic epithelium. Methods Gene expression levels of AGR2 were examined in prostate cancer cells by microarray analysis. We further examined the relationship of AGR2 protein expression to histopathology and prostate cancer outcome on a population basis using tissue microarray technology. Results At the RNA and protein level, there was an increase in AGR2 expression in adenocarcinoma of the prostate compared to morphologically normal prostatic glandular epithelium. Using a tissue microarray, this enhanced AGR2 expression was seen as early as premalignant PIN lesions. Interestingly, within adenocarcinoma samples, there was a slight trend toward lower levels of AGR2 with increasing Gleason score. Consistent with this, relatively lower levels of AGR2 were highly predictive of disease recurrence in patients who had originally presented with high-stage primary prostate cancer (P = 0.009. Conclusions We have shown for the first time that despite an increase in AGR2 expression in prostate cancer compared to non-malignant cells, relatively lower levels of AGR2 are highly predictive of disease recurrence following radical prostatectomy.

  15. AGR-2 safety test predictions using the PARFUME code

    Energy Technology Data Exchange (ETDEWEB)

    Collin, Blaise P. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    This report documents calculations performed to predict failure probability of TRISO-coated fuel particles and diffusion of fission products through these particles during safety tests following the second irradiation test of the Advanced Gas Reactor program (AGR-2). The calculations include the modeling of the AGR-2 irradiation that occurred from June 2010 to October 2013 in the Advanced Test Reactor (ATR) and the modeling of a safety testing phase to support safety tests planned at Oak Ridge National Laboratory and at Idaho National Laboratory (INL) for a selection of AGR-2 compacts. The heat-up of AGR-2 compacts is a critical component of the AGR-2 fuel performance evaluation, and its objectives are to identify the effect of accident test temperature, burnup, and irradiation temperature on the performance of the fuel at elevated temperature. Safety testing of compacts will be followed by detailed examinations of the fuel particles to further evaluate fission product retention and behavior of the kernel and coatings. The modeling was performed using the particle fuel model computer code PARFUME developed at INL. PARFUME is an advanced gas-cooled reactor fuel performance modeling and analysis code (Miller 2009). It has been developed as an integrated mechanistic code that evaluates the thermal, mechanical, and physico-chemical behavior of fuel particles during irradiation to determine the failure probability of a population of fuel particles given the particle-to-particle statistical variations in physical dimensions and material properties that arise from the fuel fabrication process, accounting for all viable mechanisms that can lead to particle failure. The code also determines the diffusion of fission products from the fuel through the particle coating layers, and through the fuel matrix to the coolant boundary. The subsequent release of fission products is calculated at the compact level (release of fission products from the compact). PARFUME calculates the

  16. AGR-2 Safety Test Predictions Using the PARFUME Code

    Energy Technology Data Exchange (ETDEWEB)

    Blaise Collin

    2014-09-01

    This report documents calculations performed to predict failure probability of TRISO-coated fuel particles and diffusion of fission products through these particles during safety tests following the second irradiation test of the Advanced Gas Reactor program (AGR-2). The calculations include the modeling of the AGR-2 irradiation that occurred from June 2010 to October 2013 in the Advanced Test Reactor (ATR) and the modeling of a safety testing phase to support safety tests planned at Oak Ridge National Laboratory and at Idaho National Laboratory (INL) for a selection of AGR-2 compacts. The heat-up of AGR-2 compacts is a critical component of the AGR-2 fuel performance evaluation, and its objectives are to identify the effect of accident test temperature, burnup, and irradiation temperature on the performance of the fuel at elevated temperature. Safety testing of compacts will be followed by detailed examinations of the fuel particles to further evaluate fission product retention and behavior of the kernel and coatings. The modeling was performed using the particle fuel model computer code PARFUME developed at INL. PARFUME is an advanced gas-cooled reactor fuel performance modeling and analysis code (Miller 2009). It has been developed as an integrated mechanistic code that evaluates the thermal, mechanical, and physico-chemical behavior of fuel particles during irradiation to determine the failure probability of a population of fuel particles given the particle-to-particle statistical variations in physical dimensions and material properties that arise from the fuel fabrication process, accounting for all viable mechanisms that can lead to particle failure. The code also determines the diffusion of fission products from the fuel through the particle coating layers, and through the fuel matrix to the coolant boundary. The subsequent release of fission products is calculated at the compact level (release of fission products from the compact). PARFUME calculates the

  17. Safety testing of AGR-2 UO2 compacts 3-3-2 and 3-4-2

    Energy Technology Data Exchange (ETDEWEB)

    Hunn, John D. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Morris, Robert Noel [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Baldwin, Charles A. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States); Montgomery, Fred C. [Oak Ridge National Laboratory (ORNL), Oak Ridge, TN (United States)

    2015-09-01

    Post-irradiation examination (PIE) is in progress on tristructural-isotropic (TRISO) coated-particle fuel compacts from the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program second irradiation experiment (AGR-2) [Collin 2014]. The AGR-2 PIE will build upon new information and understanding acquired throughout the recently-concluded six-year AGR-1 PIE campaign [Demkowicz et al. 2015] and establish a database for the different AGR-2 fuel designs.

  18. AGR-1 Irradiation Test Final As-Run Report

    Energy Technology Data Exchange (ETDEWEB)

    Blaise P. Collin

    2012-06-01

    This document presents the as-run analysis of the AGR-1 irradiation experiment. AGR-1 is the first of eight planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the US Department of Energy (DOE) as part of the Next-Generation Nuclear Plant (NGNP) project. The objectives of the AGR-1 experiment are: 1. To gain experience with multi-capsule test train design, fabrication, and operation with the intent to reduce the probability of capsule or test train failure in subsequent irradiation tests. 2. To irradiate fuel produced in conjunction with the AGR fuel process development effort. 3. To provide data that will support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. In order to achieve the test objectives, the AGR-1 experiment was irradiated in the B-10 position of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) for a total duration of 620 effective full power days of irradiation. Irradiation began on December 24, 2006 and ended on November 6, 2009 spanning 13 ATR cycles and approximately three calendar years. The test contained six independently controlled and monitored capsules. Each capsule contained 12 compacts of a single type, or variant, of the AGR coated fuel. No fuel particles failed during the AGR-1 irradiation. Final burnup values on a per compact basis ranged from 11.5 to 19.6 %FIMA, while fast fluence values ranged from 2.21 to 4.39 ?1025 n/m2 (E >0.18 MeV). We’ll say something here about temperatures once thermal recalc is done. Thermocouples performed well, failing at a lower rate than expected. At the end of the irradiation, nine of the originally-planned 19 TCs were considered functional. Fission product release-to-birth (R/B) ratios were quite low. In most capsules, R/B values at the end of the irradiation were at or below 10-7 with only one

  19. La Misión del Agrónomo

    Directory of Open Access Journals (Sweden)

    Caicedo A.

    1942-08-01

    Full Text Available La agronomía, como todas las profesiones que surgen en el plano de las necesidades sociales, estará sujeta en sus primeros años de existencia a un proceso riguroso de adaptación. La primera fuerza opositora que halla el agrónomo en su labor es la impreparación ciega y el empirismo secular del campesino, quien cree abarcar todos los conocimientos y dominar todos los aspectos de su oficio. Aparte de esta misión exclusivamente social y por demás larga y difícil, caracteriza al agrónomo su calidad de creador de riqueza nacional.

  20. AGR-2 IRRADIATION TEST FINAL AS-RUN REPORT

    Energy Technology Data Exchange (ETDEWEB)

    Blaise, Collin

    2014-07-01

    This document presents the as-run analysis of the AGR-2 irradiation experiment. AGR-2 is the second of the planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the U.S. Department of Energy as part of the Very High Temperature Reactor (VHTR) Technical Development Office (TDO) program. The objectives of the AGR-2 experiment are to: (a) Irradiate UCO (uranium oxycarbide) and UO2 (uranium dioxide) fuel produced in a large coater. Fuel attributes are based on results obtained from the AGR-1 test and other project activities. (b) Provide irradiated fuel samples for post-irradiation experiment (PIE) and safety testing. (c) Support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. The primary objective of the test was to irradiate both UCO and UO2 TRISO (tri-structural isotropic) fuel produced from prototypic scale equipment to obtain normal operation and accident condition fuel performance data. The UCO compacts were subjected to a range of burnups and temperatures typical of anticipated prismatic reactor service conditions in three capsules. The test train also includes compacts containing UO2 particles produced independently by the United States, South Africa, and France in three separate capsules. The range of burnups and temperatures in these capsules were typical of anticipated pebble bed reactor service conditions. The results discussed in this report pertain only to U.S. produced fuel. In order to achieve the test objectives, the AGR-2 experiment was irradiated in the B-12 position of the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) for a total irradiation duration of 559.2 effective full power days (EFPD). Irradiation began on June 22, 2010, and ended on October 16, 2013, spanning 12 ATR power cycles and approximately three and a half calendar years. The test

  1. Phenotypic characterization and virulence of a sae- agr- mutant of Staphylococcus aureus.

    Science.gov (United States)

    Giraudo, A T; Rampone, H; Calzolari, A; Nagel, R

    1996-02-01

    A sae::Tn551 agr::tetM double mutant was constructed and characterized. The production of several exoproteins (e.g., beta-hemolysin, DNase, and proteases) by this mutant was determined and found to be lower than the already diminished production of either isogenic single mutant sae- or agr-. The double mutant also showed, like the agr- mutant, null production of alpha- and delta-hemolysins and diminished levels of lipase. The reduced levels of many exoproteins in the double mutant as compared with their already diminished levels in either single mutant suggest that there is an additive or synergistic interaction between the two mutations involved, sae- and agr-. However, inactivation of both loci, sae and agr, had a different effect on the two exoproteins that are up regulated in the agr- mutant; thus, coagulase dropped to levels close to the null levels of the sae- parental strain, while extracellular protein A displayed the high levels characteristic of the agr- single mutant. The virulence of the sae- agr- double mutant, determined by intraperitoneal injection in mice, was found to be significantly diminished as compared with that of the sae+ agr+ parental strain or the sae- agr+ single mutant.

  2. AGR2 is induced in asthma and promotes allergen-induced mucin overproduction.

    Science.gov (United States)

    Schroeder, Bradley W; Verhaeghe, Catherine; Park, Sung-Woo; Nguyenvu, Louis T; Huang, Xiaozhu; Zhen, Guohua; Erle, David J

    2012-08-01

    Mucins are gel-forming proteins that are responsible for the characteristic viscoelastic properties of mucus. Mucin overproduction is a hallmark of asthma, but the cellular requirements for airway mucin production are poorly understood. The endoplasmic reticulum (ER) protein anterior gradient homolog 2 (AGR2) is required for production of the intestinal mucin MUC2, but its role in the production of the airway mucins MUC5AC and MUC5B is not established. Microarray data were analyzed to examine the relationship between AGR2 and MUC5AC expression in asthma. Immunofluorescence was used to localize AGR2 in airway cells. Coimmunoprecipitation was used to identify AGR2-immature MUC5AC complexes. Agr2(-/-) mice were used to determine the role of AGR2 in allergic airway disease. AGR2 localized to the ER of MUC5AC- and MUC5B-producing airway cells and formed a complex with immature MUC5AC. AGR2 expression increased together with MUC5AC expression in airway epithelium from "Th2-high" asthmatics. Allergen-challenged Agr2(-/-) mice had greater than 50% reductions in MUC5AC and MUC5B proteins compared with allergen-challenged wild-type mice. Impaired mucin production in Agr2(-/-) mice was accompanied by an increase in the proportion of mucins contained within the ER and by evidence of ER stress in airway epithelium. This study shows that AGR2 increases with mucin overproduction in individuals with asthma and in mouse models of allergic airway disease. AGR2 interacts with immature mucin in the ER and loss of AGR2 impairs allergen-induced MUC5AC and MUC5B overproduction.

  3. Trabajadores agrícolas y subjetividad en California

    Directory of Open Access Journals (Sweden)

    Florencio Posadas Segura

    2014-01-01

    Full Text Available En este trabajo se explora el problema de la subjetividad de los trabajadores agríco - las, partiendo de la hipótesis de que éstos consideran malas sus condiciones de vida y de trabajo. Mediante el trabajo de campo se demostraron sus conocimientos y opi - niones sobre su situación laboral y existencial en el Valle de San Joaquín California durante 2007 y 2008. Se descubrió que la visión del trabajador agrícola está basada en la subjetivación y reinterpretación de sus circunstancias objetivas de trabajo y de vida. Se concluyó que los trabajadores agrícolas opinan que sus condiciones son pé - simas porque sus derechos laborales, sociales y humanos no se reconocen o respetan, la crisis económica, social y política de Estados Unidos les perjudica y el Tratado de Libre Comercio entre México, Estados Unidos y Canadá ( TLCAN sólo podría beneficiarles con una reforma migratoria.

  4. XerC Contributes to Diverse Forms of Staphylococcus aureus Infection via agr-Dependent and agr-Independent Pathways.

    Science.gov (United States)

    Atwood, Danielle N; Beenken, Karen E; Loughran, Allister J; Meeker, Daniel G; Lantz, Tamara L; Graham, Justin W; Spencer, Horace J; Smeltzer, Mark S

    2016-04-01

    We demonstrate that mutation of xerC, which reportedly encodes a homologue of an Escherichia coli recombinase, limits biofilm formation in the methicillin-resistant Staphylococcus aureus strain LAC and the methicillin-sensitive strain UAMS-1. This was not due to the decreased production of the polysaccharide intracellular adhesin (PIA) in either strain because the amount of PIA was increased in a UAMS-1xerC mutant and undetectable in both LAC and its isogenic xerC mutant. Mutation of xerC also resulted in the increased production of extracellular proteases and nucleases in both LAC and UAMS-1, and limiting the production of either class of enzymes increased biofilm formation in the isogenic xerC mutants. More importantly, the limited capacity to form a biofilm was correlated with increased antibiotic susceptibility in both strains in the context of an established biofilm in vivo. Mutation of xerC also attenuated virulence in a murine bacteremia model, as assessed on the basis of the bacterial loads in internal organs and overall lethality. It also resulted in the decreased accumulation of alpha toxin and the increased accumulation of protein A. These findings suggest that xerC may impact the functional status of agr. This was confirmed by demonstrating the reduced accumulation of RNAIII and AgrA in LAC and UAMS-1xerC mutants. However, this cannot account for the biofilm-deficient phenotype of xerC mutants because mutation of agr did not limit biofilm formation in either strain. These results demonstrate that xerC contributes to biofilm-associated infections and acute bacteremia and that this is likely due to agr-independent and -dependent pathways, respectively.

  5. AGR 3/4 Irradiation Test Final As Run Report

    Energy Technology Data Exchange (ETDEWEB)

    Collin, Blaise P. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-06-01

    Several fuel and material irradiation experiments have been planned for the Idaho National Laboratory Advanced Reactor Technologies Technology Development Office Advanced Gas Reactor Fuel Development and Qualification Program (referred to as the INL ART TDO/AGR fuel program hereafter), which supports the development and qualification of tristructural-isotropic (TRISO) coated particle fuel for use in HTGRs. The goals of these experiments are to provide irradiation performance data to support fuel process development, qualify fuel for normal operating conditions, support development and validation of fuel performance and fission product transport models and codes, and provide irradiated fuel and materials for post irradiation examination and safety testing (INL 05/2015). AGR-3/4 combined the third and fourth in this series of planned experiments to test TRISO coated low enriched uranium (LEU) oxycarbide fuel. This combined experiment was intended to support the refinement of fission product transport models and to assess the effects of sweep gas impurities on fuel performance and fission product transport by irradiating designed-to-fail fuel particles and by measuring subsequent fission metal transport in fuel-compact matrix material and fuel-element graphite. The AGR 3/4 fuel test was successful in irradiating the fuel compacts to the burnup and fast fluence target ranges, considering the experiment was terminated short of its initial 400 EFPD target (Collin 2015). Out of the 48 AGR-3/4 compacts, 42 achieved the specified burnup of at least 6% fissions per initial heavy-metal atom (FIMA). Three capsules had a maximum fuel compact average burnup < 10% FIMA, one more than originally specified, and the maximum fuel compact average burnup was <19% FIMA for the remaining capsules, as specified. Fast neutron fluence fell in the expected range of 1.0 to 5.5×1025 n/m2 (E >0.18 MeV) for all compacts. In addition, the AGR-3/4 experiment was globally successful in keeping the

  6. AGR-5/6/7 Irradiation Test Predictions using PARFUME

    Energy Technology Data Exchange (ETDEWEB)

    Skerjanc, William F.

    2017-09-14

    PARFUME, (PARticle FUel ModEl) a fuel performance modeling code used for high temperature gas-cooled reactors (HTGRs), was used to model the Advanced Gas Reactor (AGR)-5/6/7 irradiation test using predicted physics and thermal hydraulics data. The AGR-5/6/7 test consists of the combined fifth, sixth, and seventh planned irradiations of the AGR Fuel Development and Qualification Program. The AGR-5/6/7 test train is a multi-capsule, instrumented experiment that is designed for irradiation in the 133.4-mm diameter north east flux trap (NEFT) position of Advanced Test Reactor (ATR). Each capsule contains compacts filled with uranium oxycarbide (UCO) unaltered fuel particles. This report documents the calculations performed to predict the failure probability of tristructural isotropic (TRISO)-coated fuel particles during the AGR-5/6/7 experiment. In addition, this report documents the calculated source term from the driver fuel. The calculations include modeling of the AGR-5/6/7 irradiation that is scheduled to occur from October 2017 to April 2021 over a total of 13 ATR cycles, including nine normal cycles and four Power Axial Locator Mechanism (PALM) cycle for a total between 500 – 550 effective full power days (EFPD). The irradiation conditions and material properties of the AGR-5/6/7 test predicted zero fuel particle failures in Capsules 1, 2, and 4. Fuel particle failures were predicted in Capsule 3 due to internal particle pressure. These failures were predicted in the highest temperature compacts. Capsule 5 fuel particle failures were due to inner pyrolytic carbon (IPyC) cracking causing localized stresses concentrations in the SiC layer. This capsule predicted the highest particle failures due to the lower irradiation temperature. In addition, shrinkage of the buffer and IPyC layer during irradiation resulted in formation of a buffer-IPyC gap. The two capsules at the two ends of the test train, Capsules 1 and 5 experienced the smallest buffer-IPyC gap

  7. Chitinase expression in Listeria monocytogenes is positively regulated by the Agr system.

    Directory of Open Access Journals (Sweden)

    Dafni Katerina Paspaliari

    Full Text Available The food-borne pathogen Listeria monocytogenes encodes two chitinases, ChiA and ChiB, which allow the bacterium to hydrolyze chitin, the second most abundant polysaccharide in nature. Intriguingly, despite the absence of chitin in human and mammalian hosts, both of the chitinases have been deemed important for infection, through a mechanism that, at least in the case of ChiA, involves modulation of host immune responses. In this study, we show that the expression of the two chitinases is subject to regulation by the listerial agr system, a homologue of the agr quorum-sensing system of Staphylococcus aureus, that has so far been implicated in virulence and biofilm formation. We demonstrate that in addition to these roles, the listerial agr system is required for efficient chitin hydrolysis, as deletion of agrD, encoding the putative precursor of the agr autoinducer, dramatically decreased chitinolytic activity on agar plates. Agr was specifically induced in response to chitin addition in stationary phase and agrD was found to regulate the amount of chiA, but not chiB, transcripts. Although the transcript levels of chiB did not depend on agrD, the extracellular protein levels of both chitinases were reduced in the ΔagrD mutant. The regulatory effect of agr on chiA is potentially mediated through the small RNA LhrA, which we show here to be negatively regulated by agr. LhrA is in turn known to repress chiA translation by binding to the chiA transcript and interfering with ribosome recruitment. Our results highlight a previously unrecognized role of the agr system and suggest that autoinducer-based regulation of chitinolytic systems may be more commonplace than previously thought.

  8. Produção territorial das reformas agrárias no Brasil

    OpenAIRE

    Rocha, Herivelto Fernandes [UNESP

    2013-01-01

    A Reforma Agrária no Brasil é um debate atual que necessita ser realizado. A diversidade dos territórios produzidos por esta política pública a partir das várias políticas de obtenção de terras, nos motivou a realizar este estudo. Nele vimos que a Reforma Agrária brasileira perpassa por ao menos três possibilidades, a saber: a Reforma Agrária Estrutural, que faz parte das reinvindicações dos movimentos socioterritoriais; a Reforma Agrária Marginal, implementada principalmente pelos governos m...

  9. Microscopic analysis of irradiated AGR-1 coated particle fuel compacts

    Energy Technology Data Exchange (ETDEWEB)

    Scott Ploger; Paul Demkowicz; John Hunn; Robert Morris

    2012-10-01

    The AGR-1 experiment involved irradiation of 72 TRISO-coated particle fuel compacts to a peak burnup of 19.5% FIMA with no in-pile failures observed out of 3×105 total particles. Irradiated AGR-1 fuel compacts have been cross-sectioned and analyzed with optical microscopy to characterize kernel, buffer, and coating behavior. Five compacts have been examined so far, spanning a range of irradiation conditions (burnup, fast fluence, and irradiation temperature) and including all four TRISO coating variations irradiated in the AGR-1 experiment. The cylindrical specimens were sectioned both transversely and longitudinally, then polished to expose between approximately 40-80 individual particles on each mount. The analysis focused primarily on kernel swelling and porosity, buffer densification and fracturing, buffer-IPyC debonding, and fractures in the IPyC and SiC layers. Characteristic morphologies have been identified, over 800 particles have been classified, and spatial distributions of particle types have been mapped. No significant spatial patterns were discovered in these cross sections. However, some trends were found between morphological types and certain behavioral aspects. Buffer fractures were found in approximately 23% of the particles, and these fractures often resulted in unconstrained kernel swelling into the open cavities. Fractured buffers and buffers that stayed bonded to IPyC layers appear related to larger pore size in kernels. Buffer-IPyC interface integrity evidently factored into initiation of rare IPyC fractures. Fractures through part of the SiC layer were found in only three particles, all in conjunction with IPyC-SiC debonding. Compiled results suggest that the deliberate coating fabrication variations influenced the frequencies of IPyC fractures, IPyC-SiC debonds, and SiC fractures.

  10. Ceramographic Examinations of Irradiated AGR-1 Fuel Compacts

    Energy Technology Data Exchange (ETDEWEB)

    Paul Demkowicz; Scott Ploger; John Hunn; Jay S. Kehn

    2012-09-01

    The AGR 1 experiment involved irradiating 72 cylindrical fuel compacts containing tri-structural isotropic (TRISO)-coated particles to a peak burnup of 19.5% fissions per initial metal atom with no in-pile failures observed out of almost 300,000 particles. Six irradiated AGR 1 fuel compacts were selected for microscopy that span a range of irradiation conditions (temperature, burnup, and fast fluence). These six compacts also included all four TRISO coating variations irradiated in the AGR experiment. The six compacts were cross-sectioned both transversely and longitudinally, mounted, ground, and polished after development of careful techniques for preserving particle structures against preparation damage. From 36 to 79 particles within each cross section were exposed near enough to midplane for optical microscopy of kernel, buffer, and coating behavior. The microstructural analysis focused on kernel swelling and porosity, buffer densification and fracture, debonding between the buffer and inner pyrolytic carbon (IPyC) layers, and fractures in the IPyC and SiC layers. Three basic particle morphologies were established according to the extent of bonding between the buffer and IPyC layers: complete debonding along the interface (Type A), no debonding along the interface (Type B), and partial debonding (Type AB). These basic morphologies were subdivided according to whether the buffer stayed intact or fractured. The resulting six characteristic morphologies were used to classify particles within each cross section, but no spatial patterns were clearly observed in any of the cross-sectional morphology maps. Although positions of particle types appeared random within compacts, examining a total of 931 classified particles allowed other relationships among morphological types to be established.

  11. Ceramographic Examinations of Irradiated AGR-1 Fuel Compacts

    Energy Technology Data Exchange (ETDEWEB)

    Paul Demkowicz; Scott Ploger; John Hunn

    2012-05-01

    The AGR 1 experiment involved irradiating 72 cylindrical fuel compacts containing tri-structural isotropic (TRISO)-coated particles to a peak burnup of 19.5% fissions per initial metal atom with no in-pile failures observed out of almost 300,000 particles. Five irradiated AGR 1 fuel compacts were selected for microscopy that span a range of irradiation conditions (temperature, burnup, and fast fluence). These five compacts also included all four TRISO coating variations irradiated in the AGR experiment. The five compacts were cross-sectioned both transversely and longitudinally, mounted, ground, and polished after development of careful techniques for preserving particle structures against preparation damage. Approximately 40 to 80 particles within each cross section were exposed near enough to mid-plane for optical microscopy of kernel, buffer, and coating behavior. The microstructural analysis focused on kernel swelling and porosity, buffer densification and fracture, debonding between the buffer and inner pyrolytic carbon (IPyC) layers, and fractures in the IPyC and SiC layers. Three basic particle morphologies were established according to the extent of bonding between the buffer and IPyC layers: complete debonding along the interface (Type A), no debonding along the interface (Type B), and partial debonding (Type AB). These basic morphologies were subdivided according to whether the buffer stayed intact or fractured. The resulting six characteristic morphologies were used to classify particles within each cross section, but no spatial patterns were clearly observed in any of the cross-sectional morphology maps. Although positions of particle types appeared random within compacts, examining a total of 830 classified particles allowed other relationships among morphological types to be established.

  12. Cancer-secreted AGR2 induces programmed cell death in normal cells

    Science.gov (United States)

    Vitello, Elizabeth A.; Quek, Sue-Ing; Kincaid, Heather; Fuchs, Thomas; Crichton, Daniel J.; Troisch, Pamela; Liu, Alvin Y.

    2016-01-01

    Anterior Gradient 2 (AGR2) is a protein expressed in many solid tumor types including prostate, pancreatic, breast and lung. AGR2 functions as a protein disulfide isomerase in the endoplasmic reticulum. However, AGR2 is secreted by cancer cells that overexpress this molecule. Secretion of AGR2 was also found in salamander limb regeneration. Due to its ubiquity, tumor secretion of AGR2 must serve an important role in cancer, yet its molecular function is largely unknown. This study examined the effect of cancer-secreted AGR2 on normal cells. Prostate stromal cells were cultured, and tissue digestion media containing AGR2 prepared from prostate primary cancer 10-076 CP and adenocarcinoma LuCaP 70CR xenograft were added. The control were tissue digestion media containing no AGR2 prepared from benign prostate 10-076 NP and small cell carcinoma LuCaP 145.1 xenograft. In the presence of tumor-secreted AGR2, the stromal cells were found to undergo programmed cell death (PCD) characterized by formation of cellular blebs, cell shrinkage, and DNA fragmentation as seen when the stromal cells were UV irradiated or treated by a pro-apoptotic drug. PCD could be prevented with the addition of the monoclonal AGR2-neutralizing antibody P3A5. DNA microarray analysis of LuCaP 70CR media-treated vs. LuCaP 145.1 media-treated cells showed downregulation of the gene SAT1 as a major change in cells exposed to AGR2. RT-PCR analysis confirmed the array result. SAT1 encodes spermidine/spermine N1-acetyltransferase, which maintains intracellular polyamine levels. Abnormal polyamine metabolism as a result of altered SAT1 activity has an adverse effect on cells through the induction of PCD. PMID:27283903

  13. de cultivos agrícolas, en la agricultura urbana

    Directory of Open Access Journals (Sweden)

    Marcial A. Méndez F.

    2006-01-01

    Full Text Available El uso de las aguas residuales se presenta como una de las fuentes alternativas para el riego en la agricultura urbana. Esto entraña un conjunto de interrogantes en cuanto a su manejo y las posibles afectaciones que ellas puedan ocasionar a los frutos cosechados, al suelo y al medio ambiente. Las informaciones que se presentan, son solo los primeros resultados de los estudios introductorios hasta ahora realizados. Las aguas residuales del afluente Luyanó en el municipio Arroyo Naranjo, de acuerdo con los análisis realizados, se clasifican como aguas de baja contaminación (según los valores DBO5 y DQO obtenidos. Estas aguas, además, toxicológicamente no constituyen un riesgo de contaminación ni para el suelo ni para el medio ambiente, aunque no deben utilizarse sin tratamiento previo en cultivos de consumo directo, dada la carga microbiana que presentan. Las parcelas experimentales que se establecieron con cultivos de zanahoria, rábano y flor del Marigold, mostraron en las primeras cosechas que es posible alcanzar en ellas altos rendimientos agrícolas, dado el valor fertilizante de estas aguas residuales. Los resultados de la cosecha del rábano, según análisis bacteriológicos realizados, no mostraron ningún tipo de contaminación. El suelo y el entorno agrícola, tampoco presentaron afectaciones.

  14. Quantity of 135I released from the AGR-1, AGR-2, and AGR-3/4 experiments and discovery of 131I at the FPMS traps during the AGR-3/4 experiment

    Energy Technology Data Exchange (ETDEWEB)

    Scates, Dawn M. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-09-01

    A series of three Advanced Gas Reactor (AGR) experiments have been conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). From 2006 through 2014, these experiments supported the development and qualification of the new U.S. tristructural isotropic (TRISO) particle fuel for Very High Temperature Reactors (VHTR). Each AGR experiment consisted of multiple fueled capsules, each plumbed for independent temperature control using a mix of helium and neon gases. The gas leaving a capsule was routed to individual Fission Product Monitor (FPM) detectors. For intact fuel particles, the TRISO particle coatings provide a substantial barrier to fission product release. However, particles with failed coatings, whether because of a minute percentage of initially defective particles, those which fail during irradiation, or those designed to fail (DTF) particles, can release fission products to the flowing gas stream. Because reactive fission product elements like iodine and cesium quickly deposit on cooler capsule components and piping structures as the effluent gas leaves the reactor core, only the noble fission gas isotopes of Kr and Xe tend to reach FPM detectors. The FPM system utilizes High Purity Germanium (HPGe) detectors coupled with a thallium activated sodium iodide NaI(Tl) scintillator. The HPGe detector provides individual isotopic information, while the NaI(Tl) scintillator is used as a gross count rate meter. During irradiation, the 135mXe concentration reaching the FPM detectors is from both direct fission and by decay of the accumulated 135I. About 2.5 hours after irradiation (ten 15.3 minute 135mXe half lives) the directly produced 135mXe has decayed and only the longer lived 135I remains as a source. Decay systematics dictate that 135mXe will be in secular equilibrium with its 135I parent, such that its production rate very nearly equals the decay rate of the

  15. Planificación de Maquinaria Agrícola

    Directory of Open Access Journals (Sweden)

    Alvarez Cardona Alberto

    1979-06-01

    Full Text Available Se entiende por planificación agrícola el conjunto de técnicas que permiten ver con anticipación suficiente la cantidad de maquinaria, tanto fuentes de potencia como implementos que serán requeridos para realizar un trabajo específico en un tiempo determinado; ó la cantidad de trabajo específico que podrá realizar un equipo con características ya definidas a través de un tiempo determinado; se analizan también bajo este concepto de planificación aquellos sistemas que permiten evaluar, controlar y ajustar la planificación propuesta a las circunstancias reales una vez iniciada ésta.

  16. AGR-5/6/7 LEUCO Kernel Fabrication Readiness Review

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, Douglas W. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Fuel Design and Development; Bailey, Kirk W. [Idaho National Lab. (INL), Idaho Falls, ID (United States). ART Quality Assurance Engineer

    2015-02-01

    In preparation for forming low-enriched uranium carbide/oxide (LEUCO) fuel kernels for the Advanced Gas Reactor (AGR) fuel development and qualification program, Idaho National Laboratory conducted an operational readiness review of the Babcock & Wilcox Nuclear Operations Group – Lynchburg (B&W NOG-L) procedures, processes, and equipment from January 14 – January 16, 2015. The readiness review focused on requirements taken from the American Society Mechanical Engineers (ASME) Nuclear Quality Assurance Standard (NQA-1-2008, 1a-2009), a recent occurrence at the B&W NOG-L facility related to preparation of acid-deficient uranyl nitrate solution (ADUN), and a relook at concerns noted in a previous review. Topic areas open for the review were communicated to B&W NOG-L in advance of the on-site visit to facilitate the collection of objective evidences attesting to the state of readiness.

  17. Acaros de importancia agrícola en Colombia.

    Directory of Open Access Journals (Sweden)

    Mesa Nora Cristina

    1999-06-01

    Full Text Available La acarología en Colombia ha contribuido de forma notoria al conocimiento de la diversidad de especies. Además los investigadores en este campo han desarrollado estudios sobre evaluación y manejo de los ácaros fitófagos. Los avances han sido importantes en los trabajos sobre aquellas especies depredadoras. Se puede afirmar que el país cuenta con información básica y aplicada sobre los ácaros, pero se necesita profundizar en algunos temas. Este documento adelanta el análisis de la retrospectiva de la acarología agrícola en el país y se detiene en consideraciones sobre las familias y especies de mayor importancia. Esta recopilación sobre los ácaros en Colombia, señala la trascendencia que tienen estos artrópodos.

  18. Nacionalismos e reforma agrária nos anos 50

    Directory of Open Access Journals (Sweden)

    Moreira Vânia Maria Losada

    1998-01-01

    Full Text Available O artigo visa recuperar os elementos fundamentais do ideário nacionalista durante a década de 1950, destacando a centralidade do conceito de desenvolvimento auto-sustentado. A diversidade política e ideológica do movimento nacionalista é problematizada através da análise de duas correntes preponderantes do período em foco: o nacional-desenvolvimentismo, de caráter liberal, e o nacionalismo econômico, isto é, a vertente defendida pelas esquerdas. Finalmente, é focalizado a importância da reforma agrária dentro do projeto social defendido sobretudo pelos nacionalistas econômicos, enquanto fator indispensável a uma industrialização com cidadania.

  19. The protein disulfide isomerase AGR2 is essential for production of intestinal mucus.

    Science.gov (United States)

    Park, Sung-Woo; Zhen, Guohua; Verhaeghe, Catherine; Nakagami, Yasuhiro; Nguyenvu, Louis T; Barczak, Andrea J; Killeen, Nigel; Erle, David J

    2009-04-28

    Protein disulfide isomerases (PDIs) aid protein folding and assembly by catalyzing formation and shuffling of cysteine disulfide bonds in the endoplasmic reticulum (ER). Many members of the PDI family are expressed in mammals, but the roles of specific PDIs in vivo are poorly understood. A recent homology-based search for additional PDI family members identified anterior gradient homolog 2 (AGR2), a protein originally presumed to be secreted by intestinal epithelial cells. Here, we show that AGR2 is present within the ER of intestinal secretory epithelial cells and is essential for in vivo production of the intestinal mucin MUC2, a large, cysteine-rich glycoprotein that forms the protective mucus gel lining the intestine. A cysteine residue within the AGR2 thioredoxin-like domain forms mixed disulfide bonds with MUC2, indicating a direct role for AGR2 in mucin processing. Mice lacking AGR2 were viable but were highly susceptible to colitis, indicating a critical role for AGR2 in protection from disease. We conclude that AGR2 is a unique member of the PDI family, with a specialized and nonredundant role in intestinal mucus production.

  20. Increasing AIP Macrocycle Size Reveals Key Features of agr Activation in Staphylococcus aureus.

    Science.gov (United States)

    Johnson, Jeffrey G; Wang, Boyuan; Debelouchina, Galia T; Novick, Richard P; Muir, Tom W

    2015-05-04

    The agr locus in the commensal human pathogen, Staphylococcus aureus, is a two-promoter regulon with allelic variability that produces a quorum-sensing circuit involved in regulating virulence within the bacterium. Secretion of unique autoinducing peptides (AIPs) and detection of their concentrations by AgrC, a transmembrane receptor histidine kinase, coordinates local bacterial population density with global changes in gene expression. The finding that staphylococcal virulence can be inhibited through antagonism of this quorum-sensing pathway has fueled tremendous interest in understanding the structure-activity relationships underlying the AIP-AgrC interaction. The defining structural feature of the AIP is a 16-membered, thiolactone-containing macrocycle. Surprisingly, the importance of ring size on agr activation or inhibition has not been explored. In this study, we address this deficiency through the synthesis and functional analysis of AIP analogues featuring enlarged and reduced macrocycles. Notably, this study is the first to interrogate AIP function by using both established cell-based reporter gene assays and newly developed in vitro AgrC-I binding and autophosphorylation activity assays. Based on our data, we present a model for robust agr activation involving a cooperative, three-points-of-contact interaction between the AIP macrocycle and AgrC.

  1. Organismo de Certificación de Implementos y Maquinaria Agrícola (OCIMA)

    OpenAIRE

    Alma Velia Ayala Garay; Marco A. Audelo Benítez; Rocío Cervantes Osornio; Dora Ma. Sangerman-Jarquín; Miguel Sánchez Hernández; Martha Garay Hernández

    2012-01-01

    La certificación resulta trascendental puesto que da seguridad al usuario final en el funcionamiento y calidad de los tractores, la creación del Organismo de Certificación de Implementos y Maquinaria Agrícola (OCIMA) dependiente del INIFAP como Organismo de Certificación de Producto en Tractores surgió como respuesta a esta necesidad; convirtiéndose en el único a nivel nacional con el propósito de autenticar a los productores agrícolas que la compra de maquinaria agrícola cumple con las espec...

  2. Los suelos agrícolas frente al sistema legislativo Mexicano

    OpenAIRE

    Maycotte Luna, Eliot

    2012-01-01

    El presente estudio sobre legislación de los suelos agrícolas en México, se basa en la técnica que define el Derecho Parlamentario jugando un papel importante para explicar el desarrollo legislativo [retrospectivo y prospectivo] sobre el uso y protección de los recursos naturales y en específico el suelo con uso agrícola frente al crecimiento urbano. Los efectos muestran que la frontera urbana sigue destruyendo cualquier tipo de suelo y más los agrícolas. Ocasionando en ...

  3. Association between the agr locus and the presence of virulence genes and pathogenesis in Staphylococcus aureus using a Caenorhabditis elegans model

    Directory of Open Access Journals (Sweden)

    Terissa A. Thompson

    2017-01-01

    Conclusions: There was a strong association between the carriage of virulence genes and the presence of the agr operon in clinical strains of S. aureus. Further, agr-positive strains were more pathogenic than agr-negative strains, suggesting a correlation between the presence of agr, carriage of virulence determinants, and pathogenicity.

  4. Cross-Talk between Staphylococcus aureus and Other Staphylococcal Species via the agr Quorum Sensing System

    DEFF Research Database (Denmark)

    Canovas de la Nuez, Jaime; Baldry, Mara; Bojer, Martin S;

    2016-01-01

    between staphylococci and S. aureus, and show that this interaction may eventually lead to the identification of new anti-virulence candidates to target S. aureus infections. Here we show that culture supernatants of 37 out of 52 staphylococcal isolates representing 17 different species inhibit S. aureus......-inducing peptides (AIPs) sensed by AgrC, a two component histidine kinase. agr loci are found also in other staphylococcal species and for Staphylococcus epidermidis, the encoded AIP represses expression of agr regulated virulence genes in S. aureus. In this study we aimed to better understand the interaction....... To assess impact on S. aureus virulence, we co-inoculated S. aureus and S. schleiferi in vivo in the Galleria mellonella wax moth larva, and found that expression of key S. aureus virulence factors was abrogated. Our data show that the S. aureus agr locus is highly responsive to other staphylococcal species...

  5. Crystal Structure of AGR_C_4470p from Agrobacterium tumefaciens

    Energy Technology Data Exchange (ETDEWEB)

    Vorobiev,S.; Neely, H.; Seetharaman, J.; Ma, L.; Xiao, R.; Acton, T.; Montelione, G.; Tong, L.

    2007-01-01

    We report here the crystal structure at 2.0 {angstrom} resolution of the AGR{_}C{_}4470p protein from the Gram-negative bacterium Agrobacterium tumefaciens. The protein is a tightly associated dimer, each subunit of which bears strong structural homology with the two domains of the heme utilization protein ChuS from Escherichia coli and HemS from Yersinia enterocolitica. Remarkably, the organization of the AGR{_}C{_}4470p dimer is the same as that of the two domains in ChuS and HemS, providing structural evidence that these two proteins evolved by gene duplication. However, the binding site for heme, while conserved in HemS and ChuS, is not conserved in AGR{_}C{_}4470p, suggesting that it probably has a different function. This is supported by the presence of two homologs of AGR{_}C{_}4470p in E. coli, in addition to the ChuS protein.

  6. Cross-talk between Staphylococcus aureus and other staphylococcal species via the agr quorum sensing system

    Directory of Open Access Journals (Sweden)

    Jaime Canovas de la Nuez

    2016-11-01

    Full Text Available Staphylococci are associated with both humans and animals. While most are non-pathogenic colonizers, Staphylococcus aureus is an opportunistic pathogen capable of causing severe infections. S. aureus virulence is controlled by the agr quorum sensing system responding to secreted auto-inducing peptides (AIPs sensed by AgrC, a two component histidine kinase. agr loci are found also in other staphylococcal species and for S. epidermidis, the encoded AIP represses expression of agr regulated virulence genes in S. aureus. In this study we aimed to determine how other staphylococci affect S. aureus agr, and if such interaction may point to new anti-virulence candidates to target S. aureus infections. Here we show that culture supernatants of 37 out of 52 staphylococcal isolates representing 17 different species inhibit S. aureus agr. The dog pathogen, S. schleiferi, expressed the most potent inhibitory activity and was active against all four agr classes found in S. aureus. By employing a S. aureus strain encoding a constitutively active AIP receptor we show that the activity is mediated via agr. Subsequent cloning and heterologous expression of the S. schleiferi AIP in S. aureus demonstrated that this molecule was likely responsible for the inhibitory activity, and further proof was provided when pure synthetic S. schleiferi AIP was able to completely abolish agr induction of an S. aureus reporter strain. To assess impact on S. aureus virulence, we co-inoculated S. aureus and S. schleiferi in vivo in the Galleria Mellonella wax moth larva, and found that expression of key S. aureus virulence factors was abrogated. Our data show that the S. aureus agr locus is highly responsive to other staphylococcal species suggesting that agr is an inter-species communication system. Based on these results we speculate that interactions between S. aureus and other colonizing staphylococci will significantly influence the ability of S. aureus to cause infection, and

  7. AGR-2 Irradiated Test Train Preliminary Inspection and Disassembly First Look

    Energy Technology Data Exchange (ETDEWEB)

    Ploger, Scott [Idaho National Lab. (INL), Idaho Falls, ID (United States); Demkowciz, Paul [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-05-01

    The AGR 2 irradiation experiment began in June 2010 and was completed in October 2013. The test train was shipped to the Materials and Fuels Complex in July 2014 for post-irradiation examination (PIE). The first PIE activities included nondestructive examination of the test train, followed by disassembly of the test train and individual capsules and detailed inspection of the capsule contents, including the fuel compacts and their graphite fuel holders. Dimensional metrology was then performed on the compacts, graphite holders, and steel capsule shells. AGR 2 disassembly and metrology were performed with the same equipment used successfully on AGR 1 test train components. Gamma spectrometry of the intact test train gave a preliminary look at the condition of the interior components. No evidence of damage to compacts or graphite components was evident from the isotopic and gross gamma scans. Disassembly of the AGR 2 test train and its capsules was conducted rapidly and efficiently by employing techniques refined during the AGR 1 disassembly campaign. Only one major difficulty was encountered while separating the test train into capsules when thermocouples (of larger diameter than used in AGR 1) and gas lines jammed inside the through tubes of the upper capsules, which required new tooling for extraction. Disassembly of individual capsules was straightforward with only a few minor complications. On the whole, AGR 2 capsule structural components appeared less embrittled than their AGR 1 counterparts. Compacts from AGR 2 Capsules 2, 3, 5, and 6 were in very good condition upon removal. Only relatively minor damage or markings were visible using high resolution photographic inspection. Compact dimensional measurements indicated radial shrinkage between 0.8 to 1.7%, with the greatest shrinkage observed on Capsule 2 compacts that were irradiated at higher temperature. Length shrinkage ranged from 0.1 to 0.9%, with by far the lowest axial shrinkage on Capsule 3 compacts

  8. High temperature and pressure effects on the elastic properties of B2 intermetallics AgRE

    OpenAIRE

    Liu Lili; Wu Xiaozhi; Li Weiguo; Wang Rui; Liu Qing

    2015-01-01

    The high temperature and pressure effects on the elastic properties of the AgRE (RE=Sc, Tm, Er, Dy, Tb) intermetallic compounds with B2 structure have been performed from first principle calculations. For the temperature range 0-1000 K, the second order elastic constants for all the AgRE intermetallic compounds follow a normal behavior: they decrease with increasing temperature. The pressure dependence of the second order elastic constants has been investigated on the ...

  9. Survival of Listeria monocytogenes in Soil Requires AgrA-Mediated Regulation.

    Science.gov (United States)

    Vivant, Anne-Laure; Garmyn, Dominique; Gal, Laurent; Hartmann, Alain; Piveteau, Pascal

    2015-08-01

    In a recent paper, we demonstrated that inactivation of the Agr system affects the patterns of survival of Listeria monocytogenes (A.-L. Vivant, D. Garmyn, L. Gal, and P. Piveteau, Front Cell Infect Microbiol 4:160, http://dx.doi.org/10.3389/fcimb.2014.00160). In this study, we investigated whether the Agr-mediated response is triggered during adaptation in soil, and we compared survival patterns in a set of 10 soils. The fate of the parental strain L. monocytogenes L9 (a rifampin-resistant mutant of L. monocytogenes EGD-e) and that of a ΔagrA deletion mutant were compared in a collection of 10 soil microcosms. The ΔagrA mutant displayed significantly reduced survival in these biotic soil microcosms, and differential transcriptome analyses showed large alterations of the transcriptome when AgrA was not functional, while the variations in the transcriptomes between the wild type and the ΔagrA deletion mutant were modest under abiotic conditions. Indeed, in biotic soil environments, 578 protein-coding genes and an extensive repertoire of noncoding RNAs (ncRNAs) were differentially transcribed. The transcription of genes coding for proteins involved in cell envelope and cellular processes, including the phosphotransferase system and ABC transporters, and proteins involved in resistance to antimicrobial peptides was affected. Under sterilized soil conditions, the differences were limited to 86 genes and 29 ncRNAs. These results suggest that the response regulator AgrA of the Agr communication system plays important roles during the saprophytic life of L. monocytogenes in soil.

  10. Data Compilation for AGR-1 Variant 3 Compact Lot LEU01-49T-Z

    Energy Technology Data Exchange (ETDEWEB)

    Hunn, John D [ORNL; Montgomery, Fred C [ORNL; Pappano, Peter J [ORNL

    2006-08-01

    This document is a compilation of characterization data for the AGR-1 vriant 3 fuel compact lot LEU01-49T-Z. The compacts were produced by ORNL for the Advanced Gas Reactor Fuel Development and Qualification (AGR) program for the first AGR irradiation test train (AGR-1). This compact lot was fabricated using particle composite LEU01-49T, which was a composite of three batches of TRISO-coated 350 {micro}m diameter 19.7% low enrichment uranium oxide/uranium carbide kernels (LEUCO). The AGR-1 TRISO-coated particles consist of a spherical kernel coated with an {approx} 50% dense carbon buffer layer (100 {micro}m nominal thickness), followed by a dense inner pyrocarbon layer (40 {micro}m nominal thickness), followed by a SiC layer (35 {micro}m nominal thickness), followed by another dense outer pyrocarbon layer (40 {micro}m nominal thickness). The kernels were obtained from BWXT and identified as composite G73D-20-69302. The BWXT kernel lot G73D-20-69302 was riffled into sublots for characterization and coating by ORNL and identified as LEU01-?? (where ?? is a series of integers beginning with 01). A data compilation for the AGR-1 variant 3 coated particle composite LEU01-49t CAN BE FOUND IN ornl/tm-2006/022.

  11. The Agr communication system provides a benefit to the populations of Listeria monocytogenes in soil.

    Science.gov (United States)

    Vivant, Anne-Laure; Garmyn, Dominique; Gal, Laurent; Piveteau, Pascal

    2014-01-01

    In this study, we investigated whether the Agr communication system of the pathogenic bacterium Listeria monocytogenes was involved in adaptation and competitiveness in soil. Alteration of the ability to communicate, either by deletion of the gene coding the response regulator AgrA (response-negative mutant) or the signal pro-peptide AgrD (signal-negative mutant), did not affect population dynamics in soil that had been sterilized but survival was altered in biotic soil suggesting that the Agr system of L. monocytogenes was involved to face the complex soil biotic environment. This was confirmed by a set of co-incubation experiments. The fitness of the response-negative mutant was lower either in the presence or absence of the parental strain but the fitness of the signal-negative mutant depended on the strain with which it was co-incubated. The survival of the signal-negative mutant was higher when co-cultured with the parental strain than when co-cultured with the response-negative mutant. These results showed that the ability to respond to Agr communication provided a benefit to listerial cells to compete. These results might also indicate that in soil, the Agr system controls private goods rather than public goods.

  12. Staphylococcus aureus interaction with phospholipid vesicles--a new method to accurately determine accessory gene regulator (agr activity.

    Directory of Open Access Journals (Sweden)

    Maisem Laabei

    Full Text Available The staphylococcal accessory gene regulatory (agr operon is a well-characterised global regulatory element that is important in the control of virulence gene expression for Staphylococcus aureus, a major human pathogen. Hence, accurate and sensitive measurement of Agr activity is central in understanding the virulence potential of Staphylococcus aureus, especially in the context of Agr dysfunction, which has been linked with persistent bacteraemia and reduced susceptibility to glycopeptide antibiotics. Agr function is typically measured using a synergistic haemolysis CAMP assay, which is believe to report on the level of expression of one of the translated products of the agr locus, delta toxin. In this study we develop a vesicle lysis test (VLT that is specific to small amphipathic peptides, most notably delta and Phenol Soluble Modulin (PSM toxins. To determine the accuracy of this VLT method in assaying Agr activity, we compared it to the CAMP assay using 89 clinical Staphylococcus aureus isolates. Of the 89 isolates, 16 were designated as having dysfunctional Agr systems by the CAMP assay, whereas only three were designated as such by VLT. Molecular analysis demonstrated that of these 16 isolates, the 13 designated as having a functional Agr system by VLT transcribed rnaIII and secreted delta toxin, demonstrating they have a functional Agr system despite the results of the CAMP assay. The agr locus of all 16 isolates was sequenced, and only the 3 designated as having a dysfunctional Agr system contained mutations, explaining their Agr dysfunction. Given the potentially important link between Agr dysfunction and clinical outcome, we have developed an assay that determines this more accurately than the conventional CAMP assay.

  13. Obreros agrícolas migrantes en Sinaloa

    Directory of Open Access Journals (Sweden)

    Florencio Posadas Segura

    2015-01-01

    Full Text Available el objetivo de este artículo es demostrar la presencia sig-nificativa de los obreros agrícolas migrantes, algunas carac-terísticas que la explican y la pauperización que experimen-tan. La causa principal de la migración es la desocupación;los empresarios controlan los métodos de contratación, tras-portación y explotación, y los jornaleros rurales migrantestrabajan más, ganan menos y su situación es mayormentemiserable. Esto se ilustra con el caso de Villa Benito Juárez,Sinaloa, que prueba la gran importancia de los asalariadosestacionales del campo, como auténticos productores de lariqueza, y la paradoja de su condición de pobreza aguda. Elpatrón migratorio interno y externo descubierto contradicelos estereotipos prevalecientes, en el marco de la reestruc-turación productiva y laboral de la agricultura mexicana yla incorporación de fuerza de trabajo asalariada pagada pordebajo de su valor, segmentada y dosificada conveniente-mente de acuerdo con la estrategia del capital, guiada por elespíritu de la ganancia máxima.

  14. Data Compilation for AGR-1 Baseline Compact Lot LEU01-46T-Z

    Energy Technology Data Exchange (ETDEWEB)

    Hunn, John D [ORNL; Montgomery, Fred C [ORNL; Pappano, Peter J [ORNL

    2006-08-01

    This document is a compilation of characterization data for the AGR-1 baseline compact lot LEU01-46T-Z. The compacts were produced by ORNL for the Advanced Gas Reactor Fuel Development and Qualification (AGR) program for the first AGR irradiation test train (AGR-1). This compact lot was fabricated using particle composite LEU01-46T, which was a composite of four batches of TRISO-coated 350 {micro}m diameter 19.7% low enrichment uranium oxide/uranium carbide kernels (LEUCO). The AGR-1 TRISO-coated particles consist of a spherical kernel coated with an {approx} 50% dense carbon buffer layer (100 {micro}m nominal thickness), followed by a dense inner pyrocarbon layer (40 {micro}m nominal thickness), followed by a SiC layer (35 {micro}m nominal thickness), followed by another dense outer pyrocarbon layer (40 {micro}m nominal thickness). The kernels were obtained from BWXT and identified as composite G73D-20-69302. The BWXT kernel lot G73D-20-69302 was riffled into sublots for characterization and coating by ORNL and identified as LEU01-?? (where ?? is a series of integers beginning with 01). A data compilation for the AGR-1 baseline coated particle composite LEU01-46T can be found in ORNL/TM-2006/019. The AGR-1 Fuel product Specification and Characterization Guidance (INL EDF-4380) provides the requirements necessary for acceptance of the fuel manufactured for the AGR-1 irradiation test. Section 6.2 of EDF-4380 provides the property requirements for the heat treated compacts. The Statistical Sampling Plan for AGR Fuel materials (INL EDF-4542) provides additional guidance regarding statistical methods for product acceptance and recommended sample sizes. The procedures for characterizing and qualifying the compacts are outlined in ORNL product inspection plan AGR-CHAR-PIP-05. the inspection report forms generated by this product inspection plan document the product acceptance for the property requirements listed in section 6.2 of EDF-4380.

  15. Data Compilation for AGR-1 Variant 2 Compact Lot LEU01-48T-Z

    Energy Technology Data Exchange (ETDEWEB)

    Hunn, John D [ORNL; Montgomery, Fred C [ORNL; Pappano, Peter J [ORNL

    2006-08-01

    This document is a compilation of characterization data for the AGR-1 variant 2 compact lot LEU01-48T-Z. The compacts were produced by ORNL for the Advanced Gas Reactor Fuel Development and Qualification (AGR) program for the first AGR irradiation test train (AGR-1). This compact lot was fabricated using particle composite LEU01-48T, which was a composite of three batches of TRISO-coated 350 {micro}m diameter 19.7% low enrichment uranium oxide/uranium carbide kernels (LEUCO). The AGR-1 TRISO-coated particles consist of a spherical kernel coated with an {approx} 50% dense carbon buffer layer (100 {micro}m nominal thickness), followed by a dense inner pyrocarbon layer (40 {micro}m nominal thickness), followed by a SiC layer (35 {micro}m nominal thickness), followed by another dense outer pyrocarbon layer (40 {micro}m nominal thickness). The kernels were obtained from BWXT and identified as composite G73D-20-69302. The BWXT kernel lot G73D-20-69302 was riffled into sublots for characterization and coating by ORNL and identified as LEU01-?? (where ?? is a series of integers beginning with 01). A data compilation for the AGR-1 variant 2 coated particle composite LEU01-48T can be found in ORNL/TM-2006/021. The AGR-1 Fuel Product Specification and Characterization Guidance (INL EDF-4380) provides the requirements necessary for acceptance of the fuel manufactured for the AGR-1 irradiation test. Section 6.2 of EDF-4380 provides the property requirements for the heat treated compacts. The Statistical Sampling Plan for AGR Fuel materials (INL EDF-4542) provides additional guidance regarding statistical methods for product acceptance and recommended sample sizes. The procedures for characterizing and qualifying the compacts are outlined in ORNL product inspection plan AGR-CHAR-PIP-05. The inspection report forms generated by this product inspection plan document the product acceptance for the property requirements listed in section 6.2 of EDF-4380.

  16. Data Compilation for AGR-1 Variant 1 Compact Lot LEU01-47T-Z

    Energy Technology Data Exchange (ETDEWEB)

    Hunn, John D [ORNL; Montgomery, Fred C [ORNL; Pappano, Peter J [ORNL

    2006-08-01

    This document is a compilation of characterization data for the AGR-1 variant 1 compact lot LEU01-47T-Z. The compacts were produced by ORNL for the ADvanced Gas Reactor Fuel Development and Qualification (AGR) program for the first AGR irradiation test train (AGR-1). This compact lot was fabricated using particle composite LEU01-47T, which was a composite of three batches of TRISO-coated 350 {micro}m diameter 19.7% low enrichment uranium oxide/uranium carbide kernels (LEUCO). The AGR-1 TRISO-coated particles consist of a spherical kernel coated with an {approx} 50% dense carbon buffer layer (100 {micro}m nominal thickness), followed by a dense inner pyrocarbon layer (40 {micro}m nominal thickness), followed by a SiC layer (35 {micro}m nominal thickness), followed by another dense outer pyrcoarbon layer (40 {micro}m nominal thickness). The kernels were obtained from BWXT and identified as composite G73D-20-69302. The BWXT kernel lot G73D-20-69302 was riffled into sublots for characterization and coating by ORNL and identified at LEU01-?? (where ?? is a series of integers beginning with 01). A data compilation for the AGR-1 variant 1 coated particle composite LEU01-47T can be found in ORNL/TM-2006/020. The AGR-1 Fuel Product Specification and Characterization Guidance (INL EDF-4380) provides the requirements necessary for acceptance of the fuel manufactured for the AGR-1 irradiation test. Section 6.2 of EDF-4380 provides the property requirements for the heat treated compacts. The Statistical Sampling Plan for AGR Fuel Materials (INL EDF-4542) provides additional guidance regarding statistical methods for product acceptance and recommended sample sizes. The procedures for characterizing and qualifying the compacts are outlined in ORNL product inspection plan AGR-CHAR-PIP-05. The inspection report forms generated by this product inspection plan document the product acceptance for the property requirements listed in section 6.2 of EDF-4380.

  17. The cefazolin inoculum effect in methicillin-susceptible Staphylococcus aureus blood isolates: their association with dysfunctional accessory gene regulator (agr).

    Science.gov (United States)

    Wi, Yu Mi; Park, Young Kyoung; Moon, Chisook; Ryu, Seong Yeol; Lee, Hyuck; Ki, Hyun Kyun; Cheong, Hae Suk; Son, Jun Seong; Lee, Jin Seo; Kwon, Ki Tae; Kim, June Myong; Ha, Young Eun; Kang, Cheol In; Ko, Kwan Soo; Chung, Doo Ryeon; Peck, Kyong Ran; Song, Jae-Hoon

    2015-11-01

    We evaluated the clinical significance of the cefazolin inoculum effect (CIE) in methicillin-susceptible Staphylococcus aureus (MSSA) isolates. In total, 146 isolates were recovered from patients with MSSA bacteremia at 9 hospitals in Korea. The CIE was observed in 16 MSSA isolates, and while type A was the only detected β-lactamase in MSSA isolates exhibiting the CIE, no strains expressing type B, C, or D β-lactamases exhibited this effect. The CIE was only observed in agr group III and I isolates and was significantly more common in isolates with agr dysfunction than in those with functional agr (P<0.001). Even among isolates producing type A β-lactamase, the CIE was also prevalent in isolates with dysfunctional agr than in isolates with functional agr (P=0.025). This study demonstrates an association between the CIE of MSSA isolates and agr dysfunction, in addition to those between the CIE and type A β-lactamase.

  18. SiC layer microstructure in AGR-1 and AGR-2 TRISO fuel particles and the influence of its variation on the effective diffusion of key fission products

    Science.gov (United States)

    Gerczak, Tyler J.; Hunn, John D.; Lowden, Richard A.; Allen, Todd R.

    2016-11-01

    Tristructural isotropic (TRISO) coated particle fuel is a promising fuel form for advanced reactor concepts such as high temperature gas-cooled reactors (HTGR) and is being developed domestically under the US Department of Energy's Nuclear Reactor Technologies Initiative in support of Advanced Reactor Technologies. The fuel development and qualification plan includes a series of fuel irradiations to demonstrate fuel performance from the laboratory to commercial scale. The first irradiation campaign, AGR-1, included four separate TRISO fuel variants composed of multiple, laboratory-scale coater batches. The second irradiation campaign, AGR-2, included TRISO fuel particles fabricated by BWX Technologies with a larger coater representative of an industrial-scale system. The SiC layers of as-fabricated particles from the AGR-1 and AGR-2 irradiation campaigns have been investigated by electron backscatter diffraction (EBSD) to provide key information about the microstructural features relevant to fuel performance. The results of a comprehensive study of multiple particles from all constituent batches are reported. The observations indicate that there were microstructural differences between variants and among constituent batches in a single variant. Insights on the influence of microstructure on the effective diffusivity of key fission products in the SiC layer are also discussed.

  19. Population studies of methicillin-resistant and -sensitive Staphylococcus aureus strains reveal a lack of variability in the agrD gene, encoding a staphylococcal autoinducer peptide.

    Science.gov (United States)

    van Leeuwen, W; van Nieuwenhuizen, W; Gijzen, C; Verbrugh, H; van Belkum, A

    2000-10-01

    The virulence of Staphylococcus aureus is controlled by the accessory gene regulator (agr) system, including an extracellular inducer encoded by agrD. Variable agr PCR restriction fragment length polymorphism (RFLP) patterns of unique S. aureus strains (n = 192) were determined for a region comprising agrD and parts of the neighboring agrC and agrB genes. Twelve unique RFLP patterns were identified among S. aureus strains in general; these patterns were further specified by sequencing. All sequences could be catalogued in the three current agr groups. A major proportion of the S. aureus strains belong to agr group 1, whereas only 6% of the methicillin-susceptible S. aureus strains and 5% of the methicillin-resistant S. aureus strains belong to agr groups 2 and 3, respectively. The homology between groups varied from 75 to 80%, and within groups it varied from 96 to 100%. Different levels of sequence variability were observed in the different agr genes. agr-related bacterial interference among colonizing S. aureus strains in the noses of persistent and intermittent human carriers was studied. S. aureus strains belonging to different agr groups were encountered in the same individual. This may suggest that the activity of the agrD gene product does not define colonization dynamics, which is further substantiated by the rarity of agr group 2 and 3 strains.

  20. Safety Testing of AGR-2 UCO Compacts 5-2-2, 2-2-2, and 5-4-1

    Energy Technology Data Exchange (ETDEWEB)

    Hunn, John D [ORNL; Morris, Robert Noel [ORNL; Baldwin, Charles A [ORNL; Montgomery, Fred C [ORNL

    2016-10-01

    Post-irradiation examination (PIE) is being performed on tristructural-isotropic (TRISO) coated-particle fuel compacts from the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program second irradiation experiment (AGR-2) [Collin 2014]. This effort builds upon the understanding acquired throughout the AGR-1 PIE campaign [Demkowicz et al. 2015a] and is establishing a database for the different AGR-2 fuel designs. The AGR-2 irradiation experiment included TRISO fuel particles coated at BWX Technologies (BWXT) with a 150-mm-diameter engineering-scale coater. Two coating batches were tested in the AGR-2 irradiation experiment. Batch 93085 had 508-μm-diameter uranium dioxide (UO2) kernels. Batch 93073 had 427-μm-diameter UCO kernels, which is a kernel design where some of the uranium oxide is converted to uranium carbide during fabrication to provide a getter for oxygen liberated during fission and limit CO production. Fabrication and property data for the AGR-2 coating batches have been compiled [Barnes and Marshall 2009] and compared to AGR-1 [Phillips, Barnes, and Hunn 2010]. The AGR-2 TRISO coatings were most like the AGR-1 Variant 3 TRISO deposited in the 50-mm-diameter ORNL lab-scale coater [Hunn and Lowden 2006]. In both cases argon-dilution of the hydrogen and methyltrichlorosilane coating gas mixture employed to deposit the SiC was used to produce a finer-grain, more equiaxed SiC microstructure [Lowden 2006; Gerczak et al. 2016]. In addition to the fact that AGR-1 fuel had smaller, 350-μm-diameter UCO kernels, notable differences in the TRISO particle properties included the pyrocarbon anisotropy, which was slightly higher in the particles coated in the engineeringscale coater, and the exposed kernel defect fraction, which was higher for AGR-2 fuel due to the detected presence of particles with impact damage introduced during TRISO particle handling [Hunn 2010].

  1. Safety Testing of AGR-2 UCO Compacts 5-2-2, 2-2-2, and 5-4-1

    Energy Technology Data Exchange (ETDEWEB)

    Hunn, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Fusion and Materials for Nuclear Systems Division; Morris, Robert Noel [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Fusion and Materials for Nuclear Systems Division; Baldwin, Charles A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Fusion and Materials for Nuclear Systems Division; Montgomery, Fred C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States). Fusion and Materials for Nuclear Systems Division

    2016-08-01

    Post-irradiation examination (PIE) is being performed on tristructural-isotropic (TRISO) coated-particle fuel compacts from the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program second irradiation experiment (AGR-2). This effort builds upon the understanding acquired throughout the AGR-1 PIE campaign, and is establishing a database for the different AGR-2 fuel designs. The AGR-2 irradiation experiment included TRISO fuel particles coated at BWX Technologies (BWXT) with a 150-mm-diameter engineering-scale coater. Two coating batches were tested in the AGR-2 irradiation experiment. Batch 93085 had 508-μm-diameter uranium dioxide (UO2) kernels. Batch 93073 had 427-μm-diameter UCO kernels, which is a kernel design where some of the uranium oxide is converted to uranium carbide during fabrication to provide a getter for oxygen liberated during fission and limit CO production. Fabrication and property data for the AGR-2 coating batches have been compiled and compared to those for AGR-1. The AGR-2 TRISO coatings were most like the AGR-1 Variant 3 TRISO deposited in the 50-mm-diameter ORNL lab-scale coater. In both cases argon-dilution of the hydrogen and methyltrichlorosilane coating gas mixture employed to deposit the SiC was used to produce a finer-grain, more equiaxed SiC microstructure. In addition to the fact that AGR-1 fuel had smaller, 350-μm-diameter UCO kernels, notable differences in the TRISO particle properties included the pyrocarbon anisotropy, which was slightly higher in the particles coated in the engineering-scale coater, and the exposed kernel defect fraction, which was higher for AGR-2 fuel due to the detected presence of particles with impact damage introduced during TRISO particle handling.

  2. Selective Chemical Inhibition of agr Quorum Sensing in Staphylococcus aureus Promotes Host Defense with Minimal Impact on Resistance

    Science.gov (United States)

    Sully, Erin K.; Malachowa, Natalia; Elmore, Bradley O.; Alexander, Susan M.; Femling, Jon K.; Gray, Brian M.; DeLeo, Frank R.; Otto, Michael; Cheung, Ambrose L.; Edwards, Bruce S.; Sklar, Larry A.; Horswill, Alexander R.; Hall, Pamela R.; Gresham, Hattie D.

    2014-01-01

    Bacterial signaling systems are prime drug targets for combating the global health threat of antibiotic resistant bacterial infections including those caused by Staphylococcus aureus. S. aureus is the primary cause of acute bacterial skin and soft tissue infections (SSTIs) and the quorum sensing operon agr is causally associated with these. Whether efficacious chemical inhibitors of agr signaling can be developed that promote host defense against SSTIs while sparing the normal microbiota of the skin is unknown. In a high throughput screen, we identified a small molecule inhibitor (SMI), savirin (S. aureus virulence inhibitor) that disrupted agr-mediated quorum sensing in this pathogen but not in the important skin commensal Staphylococcus epidermidis. Mechanistic studies employing electrophoretic mobility shift assays and a novel AgrA activation reporter strain revealed the transcriptional regulator AgrA as the target of inhibition within the pathogen, preventing virulence gene upregulation. Consistent with its minimal impact on exponential phase growth, including skin microbiota members, savirin did not provoke stress responses or membrane dysfunction induced by conventional antibiotics as determined by transcriptional profiling and membrane potential and integrity studies. Importantly, savirin was efficacious in two murine skin infection models, abating tissue injury and selectively promoting clearance of agr+ but not Δagr bacteria when administered at the time of infection or delayed until maximal abscess development. The mechanism of enhanced host defense involved in part enhanced intracellular killing of agr+ but not Δagr in macrophages and by low pH. Notably, resistance or tolerance to savirin inhibition of agr was not observed after multiple passages either in vivo or in vitro where under the same conditions resistance to growth inhibition was induced after passage with conventional antibiotics. Therefore, chemical inhibitors can selectively target AgrA in

  3. La normalización y certificación de tractores agrícolas en México

    OpenAIRE

    Alma Velia Ayala Garay; Rocío Cervantes Osornio; Marco Antonio Audelo Benítez; Noé Velázquez López; José Manuel Vargas Sállago

    2013-01-01

    El tractor agrícola es la principal fuente de potencia dentro de una unidad de producción. Por lo tanto para los usuarios de maquinaria agrícola, resulta una prioridad contar con mecanismos que permitan dar seguridad al usuario final o productor agrícola en el funcionamiento y calidad de los tractores, para esto el objetivo del presente es dar a conocer la evolución de la normalización y certificación de la maquinaria agrícola en México, sus impactos y tendencias, por medio de una descripción...

  4. Ceramography of Irradiated tristructural isotropic (TRISO) Fuel from the AGR-2 Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Rice, Francine Joyce [Idaho National Lab. (INL), Idaho Falls, ID (United States); Stempien, John Dennis [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    Ceramography was performed on cross sections from four tristructural isotropic (TRISO) coated particle fuel compacts taken from the AGR-2 experiment, which was irradiated between June 2010 and October 2013 in the Advanced Test Reactor (ATR). The fuel compacts examined in this study contained TRISO-coated particles with either uranium oxide (UO2) kernels or uranium oxide/uranium carbide (UCO) kernels that were irradiated to final burnup values between 9.0 and 11.1% FIMA. These examinations are intended to explore kernel and coating morphology evolution during irradiation. This includes kernel porosity, swelling, and migration, and irradiation-induced coating fracture and separation. Variations in behavior within a specific cross section, which could be related to temperature or burnup gradients within the fuel compact, are also explored. The criteria for categorizing post-irradiation particle morphologies developed for AGR-1 ceramographic exams, was applied to the particles in the AGR-2 compacts particles examined. Results are compared with similar investigations performed as part of the earlier AGR-1 irradiation experiment. This paper presents the results of the AGR-2 examinations and discusses the key implications for fuel irradiation performance.

  5. Saúde e mercado de trabalho no Brasil: diferenciais entre ocupados agrícolas e não agrícolas

    Directory of Open Access Journals (Sweden)

    Alexandre Gori Maia

    2010-12-01

    Full Text Available Este trabalho analisa as diferenças no estado de saúde entre e dentro dos grupos de ocupados agrícolas e não agrícolas no Brasil, utilizando medidas de autoavaliação do estado de saúde captadas no suplemento da PNAD (Pesquisa Nacional por Amostra de Domicílios de 2008. As análises baseiam-se na composição socioeconômica dos ocupados agrícolas e não agrícolas e nas estimativas de equações simultâneas para captar as relações não lineares entre saúde, renda e jornada de trabalho. Um dos pressupostos do trabalho é que a baixa prevalência de saudáveis entre os ocupados agrícolas estaria associada, sobretudo, à composição socioeconômica desse grupo, e não à maior insalubridade a que os ocupados das atividades agrícolas estariam submetidos em condições socioeconômicas semelhantes às dos não agrícolas. Analogamente, a desigualdade no estado de saúde seria menor entre os ocupados agrícolas devido aos hábitos mais homogêneos, não só no que se refere ao tipo de atividade, mas também em relação à qualidade de vida e ao acesso a uma série de itens de consumo, típico das localidades menos desenvolvidas onde as atividades agrícolas prevalecem.This paper analyzes differences of health conditions between and within agricultural and non-agricultural workers in Brazil. Self-reported health measures of the Health Supplement of Pesquisa Nacional por Amostra de Domicílios (PNAD, from 2008, are used. Results are based on the description of the socioeconomic characteristics of each group of employees and on estimates of a simultaneous equation to measure non-linear relations between health conditions, income and work hours. The main hypothesis is that the lower prevalence of workers with good health among agricultural workers is mainly due to socioeconomic characteristics of this group and not necessarily to higher insalubrious conditions that such workers would be submitted to in equivalent socioeconomic conditions

  6. Competencias Profesionales del Ingeniero Agrónomo de la Universidad de Guanajuato Competencias Profesionales del Ingeniero Agrónomo de la Universidad de Guanajuato

    Directory of Open Access Journals (Sweden)

    Gabriel Córdova Duarte

    2012-02-01

    Full Text Available Buscando determinar las competencias profesionales del Ingeniero Agrónomo, se realizó una revisión bibliográfi ca de la problemática agrícola del estado de Guanajuato, sobre las características y tipos de competencias, requeridas en éste contexto. Las mismas se identificaron y clasificaron de la siguiente manera: técnicas, establecer, implementar y evaluar las diversas técnicas de producción de cultivos; realizar un uso eficiente del agua; conservar, recuperar y optimizar el suelo; seleccionar y manejar maquinaria y equipo agropecuario; diagnosticar, controlar y prevenir las plagas, malezas y enfermedades de los cultivos; las metodológicas: analizar, implementar y evaluar diversas estrategias de venta y comercialización de productos y subproductos agrícolas; administrar empresas y proyectos agrícolas; y, establecer, implementar y evaluar alternativas energéticas agrícolas; la social participativa: diseñar, implementar y evaluar diversas estrategias para el desarrollo rural. Por tanto, la formación del agrónomo debe brindar estas competencias, a fin de contribuir al mejoramiento de la problemática estatal. In order to determine the professional competencies needed by Agricultural Engineers, a bibliographic review of agricultural problems in the state of Guanajuato was performed, focused on the types and characteristics of competencies needed, which were identified and classified as follows: Techniques for the establishment, implementation, and evaluation of various methods of crop production; the efficient use of water; the conservation, recuperation, and optimization of soil; the selection and use of machinery and farming equipment; and the diagnosing, control, and prevention of weeds, vermin, and crop diseases; Methodologies for the analysis, implementation, and evaluation of various sales strategies and the commercialization of agricultural products and sub-products; the administration of companies and agricultural

  7. Biotecnología agrícola

    Directory of Open Access Journals (Sweden)

    Melgarejo, Paloma

    2014-08-01

    Full Text Available The domestication of plants can be considered as the first genetic manipulation of living organisms and it is associated with the origin of agriculture, and represents the major contribution of biotechnology to the development of mankind. The challenges the agricultural sector faces in the coming decades are population growth and the increasing demand for raw materials for food, feed, as well as the consumer preferences, environmental and legal aspects, and the overall globalisation of the economy. The agricultural biotechnology applications will undoubtedly play a role in meeting these challenges. Spain has competent scientific groups devoted to basic and applied research, with a wide knowledge on agricultural biotechnology. The transfer of the business sector needs to the scientific field, coordinating the R&D companies and research groups from universities and public research organisms is an objective to be attained in the future.La domesticación de plantas, primera manipulación genética de los organismos vivos y origen de la Agricultura, representa la mayor contribución de la biotecnología al desarrollo de la humanidad. Los retos a superar en las próximas décadas para el sector agrario están determinados por el aumento demográfico y la demanda de materias primas para alimentación humana y animal, por las preferencias en el consumo, por aspectos medioambientales y legales, y por la globalización de la economía. Las aplicaciones de la biotecnología agrícola van a jugar un papel incuestionable en el logro de estos retos. Nuestro país posee unos buenos grupos en investigación básica y aplicada, con amplios conocimientos de la agrobiotecnología. El traslado de las necesidades del sector empresarial a la investigación, coordinando los departamentos de I+D+I de las empresas y los grupos de investigación de las universidades y organismos públicos de investigación es una finalidad a conseguir en el futuro.

  8. Analysis of Fission Products on the AGR-1 Capsule Components

    Energy Technology Data Exchange (ETDEWEB)

    Paul A. Demkowicz; Jason M. Harp; Philip L. Winston; Scott A. Ploger

    2013-03-01

    The components of the AGR-1 irradiation capsules were analyzed to determine the retained inventory of fission products in order to determine the extent of in-pile fission product release from the fuel compacts. This includes analysis of (i) the metal capsule components, (ii) the graphite fuel holders, (iii) the graphite spacers, and (iv) the gas exit lines. The fission products most prevalent in the components were Ag-110m, Cs 134, Cs 137, Eu-154, and Sr 90, and the most common location was the metal capsule components and the graphite fuel holders. Gamma scanning of the graphite fuel holders was also performed to determine spatial distribution of Ag-110m and radiocesium. Silver was released from the fuel components in significant fractions. The total Ag-110m inventory found in the capsules ranged from 1.2×10 2 (Capsule 3) to 3.8×10 1 (Capsule 6). Ag-110m was not distributed evenly in the graphite fuel holders, but tended to concentrate at the axial ends of the graphite holders in Capsules 1 and 6 (located at the top and bottom of the test train) and near the axial center in Capsules 2, 3, and 5 (in the center of the test train). The Ag-110m further tended to be concentrated around fuel stacks 1 and 3, the two stacks facing the ATR reactor core and location of higher burnup, neutron fluence, and temperatures compared with Stack 2. Detailed correlation of silver release with fuel type and irradiation temperatures is problematic at the capsule level due to the large range of temperatures experienced by individual fuel compacts in each capsule. A comprehensive Ag 110m mass balance for the capsules was performed using measured inventories of individual compacts and the inventory on the capsule components. For most capsules, the mass balance was within 11% of the predicted inventory. The Ag-110m release from individual compacts often exhibited a very large range within a particular capsule.

  9. Analysis of Fission Products on the AGR-1 Capsule Components

    Energy Technology Data Exchange (ETDEWEB)

    Paul A. Demkowicz; Jason M. Harp; Philip L. Winston; Scott A. Ploger

    2013-03-01

    The components of the AGR-1 irradiation capsules were analyzed to determine the retained inventory of fission products in order to determine the extent of in-pile fission product release from the fuel compacts. This includes analysis of (i) the metal capsule components, (ii) the graphite fuel holders, (iii) the graphite spacers, and (iv) the gas exit lines. The fission products most prevalent in the components were Ag-110m, Cs 134, Cs 137, Eu-154, and Sr 90, and the most common location was the metal capsule components and the graphite fuel holders. Gamma scanning of the graphite fuel holders was also performed to determine spatial distribution of Ag-110m and radiocesium. Silver was released from the fuel components in significant fractions. The total Ag-110m inventory found in the capsules ranged from 1.2×10 2 (Capsule 3) to 3.8×10 1 (Capsule 6). Ag-110m was not distributed evenly in the graphite fuel holders, but tended to concentrate at the axial ends of the graphite holders in Capsules 1 and 6 (located at the top and bottom of the test train) and near the axial center in Capsules 2, 3, and 5 (in the center of the test train). The Ag-110m further tended to be concentrated around fuel stacks 1 and 3, the two stacks facing the ATR reactor core and location of higher burnup, neutron fluence, and temperatures compared with Stack 2. Detailed correlation of silver release with fuel type and irradiation temperatures is problematic at the capsule level due to the large range of temperatures experienced by individual fuel compacts in each capsule. A comprehensive Ag 110m mass balance for the capsules was performed using measured inventories of individual compacts and the inventory on the capsule components. For most capsules, the mass balance was within 11% of the predicted inventory. The Ag-110m release from individual compacts often exhibited a very large range within a particular capsule.

  10. Irradiation performance of AGR-1 high temperature reactor fuel

    Energy Technology Data Exchange (ETDEWEB)

    Paul A. Demkowicz; John D. Hunn; Robert N. Morris; Charles A. Baldwin; Philip L. Winston; Jason M. Harp; Scott A. Ploger; Tyler Gerczak; Isabella J. van Rooyen; Fred C. Montgomery; Chinthaka M. Silva

    2014-10-01

    The AGR-1 experiment contained 72 low-enriched uranium oxide/uranium carbide TRISO-coated particle fuel compacts in six capsules irradiated to burnups of 11.2 to 19.5% FIMA, with zero TRISO coating failures detected during the irradiation. The irradiation performance of the fuel–including the extent of fission product release and the evolution of kernel and coating microstructures–was evaluated based on detailed examination of the irradiation capsules, the fuel compacts, and individual particles. Fractional release of 110mAg from the fuel compacts was often significant, with capsule-average values ranging from 0.01 to 0.38. Analysis of silver release from individual compacts indicated that it was primarily dependent on fuel temperature history. Europium and strontium were released in small amounts through intact coatings, but were found to be significantly retained in the outer pyrocrabon and compact matrix. The capsule-average fractional release from the compacts was 1×10 4 to 5×10 4 for 154Eu and 8×10 7 to 3×10 5 for 90Sr. The average 134Cs release from compacts was <3×10 6 when all particles maintained intact SiC. An estimated four particles out of 2.98×105 experienced partial cesium release due to SiC failure during the irradiation, driving 134Cs release in two capsules to approximately 10 5. Identification and characterization of these particles has provided unprecedented insight into the nature and causes of SiC coating failure in high-quality TRISO fuel. In general, changes in coating morphology were found to be dominated by the behavior of the buffer and inner pyrolytic carbon (IPyC), and infrequently observed SiC layer damage was usually related to cracks in the IPyC. Palladium attack of the SiC layer was relatively minor, except for the particles that released cesium during irradiation, where SiC corrosion was found adjacent to IPyC cracks. Palladium, silver, and uranium were found in the SiC layer of irradiated particles, and characterization

  11. Política Agrícola Canadiense. Algunas lecciones para Argentina

    Directory of Open Access Journals (Sweden)

    Rinaldo Antonio Colomé

    2010-09-01

    Full Text Available El objetivo general de este trabajo es analizar el diseño de la política agrícola canadiense, comparándola con las de los otros países altamente desarrollados y con la de Argentina.  Los objetivos específicos son: aAnalizar la política agrícola de Canadá referida a la producción y al comercio de granos y su efecto en los mercados internacionales; bAnalizar la política agrícola y comercial de Canadá referida al sector de oferta dirigida o regulada y sus efectos en el mercado doméstico y en los internacionales; c Realizar una comparación con Argentina. 

  12. Modelos de vulnerabilidad agrícola ante los efectos del cambio climático

    Directory of Open Access Journals (Sweden)

    Claudia Hernández Ramírez

    2014-12-01

    Full Text Available La Vulnerabilidad Agrícola (VA es el resultado de la medición de la variabilidad climática dentro de un contexto de vulnerabilidad social y sectorial, que ha ido agregando conceptos e indicadores que enriquecen y complementan el análisis de la seguridad alimentaria, en el entendido que la disponibilidad de un pronóstico corresponde no solo al derecho primordial de cualquier ser humano, sino a la supervivencia del mismo. La metodología de medición de esta variable depende estrictamente del alcance de la investigación y de la disponibilidad de datos de la región y del producto agrícola seleccionado. Los modelos utilizados hasta la fecha son tres: el modelo Estructural, el modelo Espacial y la Vulnerabilidad Agrícola.

  13. DETERMINATION OF THE AGR-1 CAPSULE TO FPMS SPECTROMETER TRANSPORT VOLUMES FROM LEADOUT FLOW TEST DATA

    Energy Technology Data Exchange (ETDEWEB)

    J. K. Hartwell; J. B. Walter; D. M. Scates; M. W. Drigert

    2007-05-01

    The AGR-1 experiment is a fueled multiple-capsule irradiation experiment being conducted in the Advanced Test Reactor (ATR) in support of the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. A flow experiment conducted during the AGR-1 irradiation provided data that included the effect of flow rate changes on the decay of a short-lived radionuclide (23Ne). This data has been analyzed to determine the capsule-specific downstream transport volume through which the capsule effluents must pass before arrival at the fission product monitoring system spectrometers. These resultant transport volumes when coupled with capsule outlet flow rates determine the transport times from capsule-to-detector. In this work an analysis protocol is developed and applied in order to determine capsule-specific transport volumes to precisions of better than +/- 7%.

  14. Saberes agrícolas tradicionales como programa académico

    Directory of Open Access Journals (Sweden)

    J. Antonio Gómez Espinoza

    2008-01-01

    Full Text Available En el marco de las crisis social y ambiental del tercer milenio, se hace necesario repensar la universidad, sus paradigmas, el concepto de educación y su modelo educativo para impactar en la construcción de la nueva sociedad. Los Saberes Agrícolas Tradicionales (SAT aportan elementos conceptuales básicos para la implementación y desarrollo de una sociedad sustentable. A partir del rescate, la sistematización de los SAT y el diálogo intercultural SAT-ciencia, se propone incorporar los Saberes Agrícolas Tradicionales como programa académico en las Instituciones de Enseñanza y Aprendizaje Agrícola del nivel Superior (IEAS.

  15. Histórico e os limites da reforma agrária na contemporaneidade brasileira

    OpenAIRE

    Paulo Nakatani; Rogério Naques Faleiros; Neide César Vargas

    2012-01-01

    Objetiva-se reconstituir a trajetória da questão fundiária (e agrária) na experiência de maior concentração de riqueza e recursos vivenciada no âmbito do sistema capitalista, partindo-se da premissa de que a crescente desigualdade do modelo brasileiro passa necessariamente pela questão agrária. Num segundo momento, procede-se à análise dos limites atualmente colocados a qualquer possibilidade de uma Reforma Agrária ampla e estrutural, dados pelo avanço do agronegócio nos últimos dez anos, pel...

  16. Uncertainty Quantification of Calculated Temperatures for the AGR 3/4 Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Pham, Binh Thi-Cam [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-09-01

    A series of Advanced Gas Reactor (AGR) irradiation experiments are being conducted within the Advanced Reactor Technology (ART) Fuel Development and Qualification Program. The main objectives of the fuel experimental campaign are to provide the necessary data on fuel performance to support fuel process development, qualify a fuel design and fabrication process for normal operation and accident conditions, and support development and validation of fuel performance and fission product transport models and codes (PLN 3636, “Technical Program Plan for INL Advanced Reactor Technologies Technology Development Office/Advanced Gas Reactor Fuel Development and Qualification Program”). The AGR 3/4 test was inserted in the Northeast Flux Trap position in the Advanced Test Reactor (ATR) core at Idaho National Laboratory (INL) in December 2011 and successfully completed irradiation in mid-April 2014, resulting in irradiation of the tristructural isotropic (TRISO) fuel for 369.1 effective full-power days (EFPDs) during approximately 2.4 calendar years. The AGR 3/4 data, including the irradiation data and calculated results, were qualified and stored in the Nuclear Data Management and Analysis System (NDMAS). To support the U.S. TRISO fuel performance assessment and to provide data for validation of fuel performance and fission product transport models and codes, the daily as run thermal analysis has been performed separately on each of twelve AGR 3/4 capsules for the entire irradiation as discussed in ECAR-2807, “AGR 3/4 Daily As Run Thermal Analyses”. The ABAQUS code’s finite element-based thermal model predicts the daily average volume average (VA) fuel temperature (FT), peak FT, and graphite matrix, sleeve, and sink temperature in each capsule. The JMOCUP simulation codes were also created to perform depletion calculations for the AGR 3/4 experiment (ECAR-2753, “JMOCUP As-Run Daily Physics Depletion Calculation for the AGR 3/4 TRISO Particle Experiment in ATR

  17. La oferta agrícola, a corto y largo plazo

    OpenAIRE

    de Pablo, Juan Carlos

    2012-01-01

    Los productores agrícolas, y particularmente su dirigencia, cuentan con mi fraterna simpatía, a raíz de los sistemáticos ataques que sufren por parte de las autoridades nacionales, y la indiferencia que exhibe el resto de los dirigentes empresarios. Lo cual no implica compartir cualquier afirmación referida a lo que podría ocurrir con la producción agrícola de Argentina, en ausencia de trabas a las exportaciones e intervención directa en el mercado interno de dichos productos, tanto de índole...

  18. Readiness Review of BWXT for Fabrication of AGR 5/6/7 Compacts

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, Douglas William [Idaho National Lab. (INL), Idaho Falls, ID (United States); Sharp, Michelle Tracy [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-02-01

    In support of preparations for fabricating compacts for the Advanced Gas Reactor (AGR) fuel qualification irradiation experiments (AGR-5/6/7), Idaho National Laboratory (INL) conducted a readiness review of the BWX Technology (BWXT) procedures, processes, and equipment associated with compact fabrication activities at the BWXT Nuclear Operations Group (BWXT-NOG) facility outside Lynchburg, VirginiaVA. The readiness review used quality assurance requirements taken from the American Society of Mechanical Engineers (ASME) Nuclear Quality Assurance Standard (NQA-1-2008/1a-2009) as a basis to assess readiness to start compact fabrication.

  19. Conceptos sobre Adecuación de Tierras Agrícolas

    Directory of Open Access Journals (Sweden)

    Bustamante Muñoz Hellodoro

    1986-06-01

    Full Text Available En este artículo se pretende de una manera muy resumida mostrar algunos conceptos y principios generales sobre la adecuación de tierras agrícolas Adecuación en términos simples significa acción o efecto de proporcionar o acomodar una cosa a otra; por extensión y a manera de ensayo de definición, adecuación de tierras agrícolas consiste en crear o proporcionar las condiciones necesarias para la eficiente explotación del campo.

  20. High temperature and pressure effects on the elastic properties of B2 intermetallics AgRE

    Science.gov (United States)

    Liu, Lili; Wu, Xiaozhi; Li, Weiguo; Wang, Rui; Liu, Qing

    2015-02-01

    The high temperature and pressure effects on the elastic properties of the AgRE (RE=Sc, Tm, Er, Dy, Tb) intermetallic compounds with B2 structure have been performed from first principle calculations. For the temperature range 0-1000 K, the second order elastic constants for all the AgRE intermetallic compounds follow a normal behavior: they decrease with increasing temperature. The pressure dependence of the second order elastic constants has been investigated on the basis of the third order elastic constants. Temperature and pressure dependent elastic anisotropic parameters A have been calculated based on the temperature and pressure dependent elastic constants.

  1. A eficiência nas caixas de Crédito Agrícola Mútuo

    OpenAIRE

    Pina, Licínio Manuel Prata

    2012-01-01

    Mestrado em Economia Portuguesa e Integração Internacional O Crédito Agrícola é o único banco cooperativo em actividade no mercado português. Constituído actualmente por oitenta e cinco caixas agrícolas e a caixa central, que sustentam a base do grupo com presença em quase todo o território nacional, caracteriza-se pela prática de banca de proximidade e de grande envolvimento com as comunidades locais, tentando contrariar a tendência para a centralidade territorial. O grupo ...

  2. Diseño de un registrador de esfuerzos para maquinaria agrícola

    OpenAIRE

    2016-01-01

    La agricultura de precisión requiere de herramientas tecnológicas para la adquisición, registro y procesamiento de la información. La incorporación de los sistemas embebidos a la maquinaria agrícola permite realizar el control y monitoreo de forma constante y precisa de las variables que influyen en el rendimiento y afectan a la correcta utilización de la maquinaria. La eficiencia del tractor agrícola puede determinarse como la relación entre el consumo de combustible y la energía mecánica...

  3. CD147 and AGR2 expression promote cellular proliferation and metastasis of head and neck squamous cell carcinoma

    Energy Technology Data Exchange (ETDEWEB)

    Sweeny, Larissa, E-mail: larissasweeny@gmail.com [Department of Surgery, University of Alabama, Division of Otolaryngology-Head and Neck Surgery, 1670 University Boulevard, Volker Hall G082, Birmingham, Alabama (United States); Liu, Zhiyong; Bush, Benjamin D.; Hartman, Yolanda [Department of Surgery, University of Alabama, Division of Otolaryngology-Head and Neck Surgery, 1670 University Boulevard, Volker Hall G082, Birmingham, Alabama (United States); Zhou, Tong [Department of Medicine, Division of Immunology and Rheumatology, 1825 University Boulevard, Shelby Biomedical Research Building 302, Birmingham, Alabama (United States); Rosenthal, Eben L., E-mail: oto@uab.edu [Department of Surgery, University of Alabama, Division of Otolaryngology-Head and Neck Surgery, 1670 University Boulevard, Volker Hall G082, Birmingham, Alabama (United States)

    2012-08-15

    The signaling pathways facilitating metastasis of head and neck squamous cell carcinoma (HNSCC) cells are not fully understood. CD147 is a transmembrane glycoprotein known to induce cell migration and invasion. AGR2 is a secreted peptide also known to promote cell metastasis. Here we describe their importance in the migration and invasion of HNSCC cells (FADU and OSC-19) in vitro and in vivo. In vitro, knockdown of CD147 or AGR2 decreased cellular proliferation, migration and invasion. In vivo, knockdown of CD147 or AGR2 expression decreased primary tumor growth as well as regional and distant metastasis. -- Highlights: Black-Right-Pointing-Pointer We investigated AGR2 in head and neck squamous cell carcinoma for the first time. Black-Right-Pointing-Pointer We explored the relationship between AGR2 and CD147 for the first time. Black-Right-Pointing-Pointer AGR2 and CD147 appear to co-localize in head and squamous cell carcinoma samples. Black-Right-Pointing-Pointer Knockdown of both AGR2 and CD147 reduced migration and invasion in vitro. Black-Right-Pointing-Pointer Knockdown of both AGR2 and CD147 decreased metastasis in vivo.

  4. Association between the agr locus and the presence of virulence genes and pathogenesis in Staphylococcus aureus using a Caenorhabditis elegans model.

    Science.gov (United States)

    Thompson, Terissa A; Brown, Paul D

    2017-01-01

    Staphylococcus aureus is a commensal pathogen with a virulon that is under agr control. agr dysfunction has been seen in clinical strains that do not respond positively to treatment. This study aimed to establish the association between the genes in the virulon and the presence of agr and to determine the relationship between the presence or absence of agr and pathogenicity. PCR was used to identify the presence of the agr operon in 101 clinical S. aureus strains. δ-Haemolysin screening was conducted on all agr-positive strains using the blood agar assay. Singleplex and/or multiplex PCR was used to determine the presence of 31 virulence genes in the strains. Caenorhabditis elegans infectivity and lifespan assays were conducted using 30 CF512 nematodes per strain in triplicate. Significance associated with the carriage of virulence and agr genes was determined using the Chi-square test. Nematode survival was measured using Kaplan-Meier survival estimates and differences in survival were assessed using the log-rank test. The frequency of agr-negative strains was 20%. All groups of virulence genes were significantly associated with agr-positive strains: enterotoxin (paureus. Further, agr-positive strains were more pathogenic than agr-negative strains, suggesting a correlation between the presence of agr, carriage of virulence determinants, and pathogenicity. Copyright © 2016 The Author(s). Published by Elsevier Ltd.. All rights reserved.

  5. Cross-Talk between Staphylococcus aureus and Other Staphylococcal Species via the agr Quorum Sensing System

    DEFF Research Database (Denmark)

    Canovas de la Nuez, Jaime; Baldry, Mara; Bojer, Martin S;

    2016-01-01

    Staphylococci are associated with both humans and animals. While most are non-pathogenic colonizers, Staphylococcus aureus is an opportunistic pathogen capable of causing severe infections. S. aureus virulence is controlled by the agr quorum sensing system responding to secreted auto-inducing pep...

  6. PIE on Safety-Tested AGR-1 Compact 5-1-1

    Energy Technology Data Exchange (ETDEWEB)

    Hunn, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Morris, Robert Noel [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Baldwin, Charles A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Montgomery, Fred C. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Gerczak, Tyler J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-08-01

    Post-irradiation examination (PIE) is being performed in support of tristructural isotropic (TRISO) coated particle fuel development and qualification for High-Temperature Gas-cooled Reactors (HTGRs). AGR-1 was the first in a series of TRISO fuel irradiation experiments initiated in 2006 under the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program; this work continues to be funded by the Department of Energy's Office of Nuclear Energy as part of the Advanced Reactor Technologies (ART) initiative. AGR-1 fuel compacts were fabricated at Oak Ridge National Laboratory (ORNL) in 2006 and irradiated for three years in the Idaho National Laboratory (INL) Advanced Test Reactor (ATR) to demonstrate and evaluate fuel performance under HTGR irradiation conditions. PIE is being performed at INL and ORNL to study how the fuel behaved during irradiation, and to examine fuel performance during exposure to elevated temperatures at or above temperatures that could occur during a depressurized conduction cooldown event. This report summarizes safety testing of irradiated AGR-1 Compact 5-1-1 in the ORNL Core Conduction Cooldown Test Facility (CCCTF) and post-safety testing PIE.

  7. Colorado's AgrAbility Project's Effects on KASA and Practice Changes with Agricultural Producers and Professionals

    Science.gov (United States)

    Fetsch, Robert J.; Jackman, Danielle M.

    2015-01-01

    Disability rates resulting from work-related injuries remain steadily high among farmers and ranchers. To address the gap in services within this population, USDA implemented AgrAbility nationally. Using part of Bennett's hierarchical model, the current study evaluated the KASA and practice change levels of 401 farmers and ranchers and compared…

  8. Nuevos neumáticos para tractores agrícolas

    OpenAIRE

    Arnó i Pujol, Judit; Masip Vilalta, Joan

    1997-01-01

    El neumático agrícola condiciona de forma determinante el rendimiento del tractor. Es necesario, por tanto, que el agricultar conozca las prestaciones de los neumáticos actuales. Ello le permitirá elegir el equipamiento más adecuado a sus necesidades.

  9. Advanced Gas Reactor (AGR)-5/6/7 Fuel Irradiation Experiments in the Advanced Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    A. Joseph Palmer; David A. Petti; S. Blaine Grover

    2014-04-01

    The United States Department of Energy’s Very High Temperature Reactor (VHTR) Advanced Gas Reactor (AGR) Fuel Development and Qualification Program will be irradiating up to seven separate low enriched uranium (LEU) tri-isotopic (TRISO) particle fuel (in compact form) experiments in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). These irradiations and fuel development are being accomplished to support development of the next generation reactors in the United States. The goals of the irradiation experiments are to provide irradiation performance data to support fuel process development, to qualify fuel for normal operating conditions, to support development and validation of fuel performance and fission product transport models and codes, and to provide irradiated fuel and materials for post irradiation examination (PIE) and safety testing. The experiments, which each consist of at least five separate capsules, are being irradiated in an inert sweep gas atmosphere with individual on-line temperature monitoring and control of each capsule. The sweep gases also have on-line fission product monitoring the effluent from each capsule to track performance of the fuel during irradiation. The first two experiments (designated AGR-1 and AGR-2), have been completed. The third and fourth experiments have been combined into a single experiment designated AGR-3/4, which started its irradiation in December 2011 and is currently scheduled to be completed in April 2014. The design of the fuel qualification experiment, designated AGR-5/6/7, is well underway and incorporates lessons learned from the three previous experiments. Various design issues will be discussed with particular details related to selection of thermometry.

  10. AGR3 in breast cancer: prognostic impact and suitable serum-based biomarker for early cancer detection.

    Science.gov (United States)

    Garczyk, Stefan; von Stillfried, Saskia; Antonopoulos, Wiebke; Hartmann, Arndt; Schrauder, Michael G; Fasching, Peter A; Anzeneder, Tobias; Tannapfel, Andrea; Ergönenc, Yavuz; Knüchel, Ruth; Rose, Michael; Dahl, Edgar

    2015-01-01

    Blood-based early detection of breast cancer has recently gained novel momentum, as liquid biopsy diagnostics is a fast emerging field. In this study, we aimed to identify secreted proteins which are up-regulated both in tumour tissue and serum samples of breast cancer patients compared to normal tissue and sera. Based on two independent tissue cohorts (n = 75 and n = 229) and one serum cohort (n = 80) of human breast cancer and healthy serum samples, we characterised AGR3 as a novel potential biomarker both for breast cancer prognosis and early breast cancer detection from blood. AGR3 expression in breast tumours is significantly associated with oestrogen receptor α (Pbreast tumours (multivariate hazard ratio: 2.186, 95% CI: 1.008-4.740, Pbreast cancer patients (n = 40, mainly low stage tumours) compared to healthy controls (n = 40). To develop a suitable biomarker panel for early breast cancer detection, we measured AGR2 protein in human serum samples in parallel. The combined AGR3/AGR2 biomarker panel achieved a sensitivity of 64.5% and a specificity of 89.5% as shown by receiver operating characteristic (ROC) curve statistics. Thus our data clearly show the potential usability of AGR3 and AGR2 as biomarkers for blood-based early detection of human breast cancer.

  11. Aptidão agrícola e algoritmos genéticos na organização espacial em projetos de reforma agrária

    Directory of Open Access Journals (Sweden)

    Jose Ambrósio Ferreira Neto

    2011-02-01

    Full Text Available A definição das parcelas familiares em projetos de reforma agrária envolve questões técnicas e sociais. Essas questões estão associadas principalmente às diferentes aptidões agrícolas do solo nestes projetos. O objetivo deste trabalho foi apresentar método para realizar o processo de ordenamento territorial em assentamentos de reforma agrária empregando Algoritmo Genético (AG. O AG foi testado no Projeto de Assentamento Veredas, em Minas Gerais, e implementado com base no sistema de aptidão agrícola das terras.

  12. Mecanização Agrícola. Bases de óleo-dinâmica. Transmissões hidráulicas em máquinas agrícolas

    OpenAIRE

    Peça, José

    2013-01-01

    Este trabalho destina-se a apoiar a aprendizagem de estudantes do ramo das ciências agrárias sobre aspectos relevantes das transmissões hidráulicas em máquinas agrícolas. A transmissão hidráulica efectua a transmissão de potência desde uma fonte (exemplo: o Serviço Externo do Sistema Hidráulico do tractor) para diversos actuadores hidráulicos nos equipamentos agrícolas. São apresentadas as transmissões hidráulicas de equipamentos agrícolas, com a preocupação focada na identificação dos co...

  13. Advanced Electron Microscopy and Micro analytical technique development and application for Irradiated TRISO Coated Particles from the AGR-1 Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Van Rooyen, Isabella Johanna [Idaho National Lab. (INL), Idaho Falls, ID (United States); Lillo, Thomas Martin [Idaho National Lab. (INL), Idaho Falls, ID (United States); Wen, Haiming [Idaho National Lab. (INL), Idaho Falls, ID (United States); Wright, Karen Elizabeth [Idaho National Lab. (INL), Idaho Falls, ID (United States); Madden, James Wayne [Idaho National Lab. (INL), Idaho Falls, ID (United States); Aguiar, Jeffery Andrew [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2017-01-01

    A series of up to seven irradiation experiments are planned for the Advanced Gas Reactor (AGR) Fuel Development and Quantification Program, with irradiation completed at the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) for the first experiment (i.e., AGR-1) in November 2009 for an effective 620 full power days. The objective of the AGR-1 experiment was primarily to provide lessons learned on the multi-capsule test train design and to provide early data on fuel performance for use in fuel fabrication process development and post-irradiation safety testing data at high temperatures. This report describes the advanced microscopy and micro-analysis results on selected AGR-1 coated particles.

  14. Desempleo entre los jornaleros agrícolas, un fenómeno emergente

    Directory of Open Access Journals (Sweden)

    Antonieta Barrón

    2013-01-01

    Full Text Available Este artículo tiene como propósito presentar un fenómeno no planteado en el estudio de mercados de trabajo agrícolas y empleo rural, se cuestiona la definición de desem- pleo, y se plantea cómo esta definición, asumida por el inegi, se aplica en los mercados de trabajo formales pero no en los no formales, los agrícolas. Se hacen comparaciones entre los niveles nacional y rural para concluir con los estudios de caso que refuerzan la tesis inicial, el aumento del desempleo en los mercados de trabajo rurales. A lo largo del trabajo se resaltan las diferencias por sexo y se conlcuye que el desempleo rural afecta más a las mujeres que los hombres, fenómeno contrario al de nivel nacional.

  15. AN EVENT DRIVEN SIMULATION FOR ADAPTIVE GENTLE RANDOM EARLY DETECTION (AGRED ALGORITHM

    Directory of Open Access Journals (Sweden)

    Omid Seifaddini

    2014-01-01

    Full Text Available Simulations are used to find optimum answers for problems in wide areas. Active queue management algorithms such as RED, GRED, typically use simulators like ns2 which is an open source simulator or OPNET, OMNET which are commercial simulators. However, beside the benefits of using simulators like having defined modules, parameters. There are problems such as complexity, large integrated components and licensing cost. To have an ideal balance in mentioned benefits and problems and to further complement the repository of simulators, this study presents the description of a general-purpose programming language based discrete event simulation for active queue management. This research has focused at developing a discrete event simulator to implement one of active queue management algorithms which is called AGRED. The results showed that the developed simulator has successfully produced the same results with an average deviation of 1.5% as previous simulator in AGRED.

  16. AGR-2 Irradiation Test Final As-Run Report, Rev 2

    Energy Technology Data Exchange (ETDEWEB)

    Collin, Blaise P. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2014-08-01

    This document presents the as-run analysis of the AGR-2 irradiation experiment. AGR-2 is the second of the planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the U.S. Department of Energy as part of the Very High Temperature Reactor (VHTR) Technical Development Office (TDO) program. The objectives of the AGR-2 experiment are to: (a) Irradiate UCO (uranium oxycarbide) and UO2 (uranium dioxide) fuel produced in a large coater. Fuel attributes are based on results obtained from the AGR-1 test and other project activities. (b) Provide irradiated fuel samples for post-irradiation experiment (PIE) and safety testing. (c) Support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. The primary objective of the test was to irradiate both UCO and UO2 TRISO (tri-structural isotropic) fuel produced from prototypic scale equipment to obtain normal operation and accident condition fuel performance data. The UCO compacts were subjected to a range of burnups and temperatures typical of anticipated prismatic reactor service conditions in three capsules. The test train also includes compacts containing UO2 particles produced independently by the United States, South Africa, and France in three separate capsules. The range of burnups and temperatures in these capsules were typical of anticipated pebble bed reactor service conditions. The results discussed in this report pertain only to U.S. produced fuel. In order to achieve the test objectives, the AGR-2 experiment was irradiated in the B-12 position of the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) for a total irradiation duration of 559.2 effective full power days (EFPD). Irradiation began on June 22, 2010, and ended on October 16, 2013, spanning 12 ATR power cycles and approximately three and a

  17. AGR-1 Irradiation Test Final As-Run Report, Rev. 3

    Energy Technology Data Exchange (ETDEWEB)

    Collin, Blaise P. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-01-01

    This document presents the as-run analysis of the AGR-1 irradiation experiment. AGR-1 is the first of eight planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the US Department of Energy (DOE) as part of the Next-Generation Nuclear Plant (NGNP) project. The objectives of the AGR-1 experiment are: 1. To gain experience with multi-capsule test train design, fabrication, and operation with the intent to reduce the probability of capsule or test train failure in subsequent irradiation tests. 2. To irradiate fuel produced in conjunction with the AGR fuel process development effort. 3. To provide data that will support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. In order to achieve the test objectives, the AGR-1 experiment was irradiated in the B-10 position of the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) for a total duration of 620 effective full power days of irradiation. Irradiation began on December 24, 2006 and ended on November 6, 2009 spanning 13 ATR cycles and approximately three calendar years. The test contained six independently controlled and monitored capsules. Each capsule contained 12 compacts of a single type, or variant, of the AGR coated fuel. No fuel particles failed during the AGR-1 irradiation. Final burnup values on a per compact basis ranged from 11.5 to 19.6 %FIMA, while fast fluence values ranged from 2.21 to 4.39 x 1025 n/m2 (E >0.18 MeV). We’ll say something here about temperatures once thermal recalc is done. Thermocouples performed well, failing at a lower rate than expected. At the end of the irradiation, nine of the originally-planned 19 TCs were considered functional. Fission product release-to-birth (R/B) ratios were quite low. In most capsules, R/B values at the end of the irradiation were at or below

  18. Analysis of fission gas release-to-birth ratio data from the AGR irradiations

    Energy Technology Data Exchange (ETDEWEB)

    Einerson, Jeffrey J., E-mail: jeffrey.einerson@inl.gov; Pham, Binh T.; Scates, Dawn M.; Maki, John T.; Petti, David A.

    2016-09-15

    A series of advanced gas reactor (AGR) irradiation tests is being conducted in the advanced test reactor (ATR) at Idaho National Laboratory (INL) in support of development and qualification of tristructural isotropic (TRISO) fuel used in the High temperature gas-cooled reactor (HTGR). Each AGR test consists of multiple independent capsules containing fuel compacts placed in a graphite cylinder shrouded by a steel shell. These capsules are instrumented with thermocouples (TC) embedded in the graphite enabling temperature control. For AGR-1, the first US irradiation of modern TRISO fuel completed in 2009, there were no particle failures detected. For AGR-2, a few exposed kernels existed in the fuel compacts based upon quality control data. For the AGR-3/4 experiment, particle failures in all capsules were expected because of the use of designed-to-fail (DTF) fuel particles whose kernels are identical to the driver fuel kernels and whose coatings are designed to fail under irradiation. The release-rate-to-birth-rate ratio (R/B) for each of krypton and xenon isotopes is calculated from release rates measured by the germanium detectors used in the AGR fission product monitoring (FPM) system installed downstream from each irradiated capsule. Birth rates are calculated based on the fission power in the experiment and fission product generation models. Thus, this R/B is a measure of the ability of fuel particle coating layers and compact matrix to retain fission gas atoms preventing their release into the sweep gas flow. The major factors that govern gaseous diffusion and release processes are found to be fuel material diffusion coefficient, temperature, and isotopic decay constant. To compare the release behavior among the AGR capsules and historic experiments, the R/B per failed particle is used. HTGR designers use this parameter in their fission product behavior models. For the U.S. TRISO fuel, a regression analysis is performed to establish functional relationships

  19. Desarrollo y perspectiva de la ingeniería agrícola

    OpenAIRE

    Ospina Mejía, Julio E.; Carlos A. González M.

    2011-01-01

    La Ingeniería Agrícola es la rama de la ingeniería orientada a dar respuesta a los problemas que plantea la agricultura moderna, mediante la aplicación de principios de las ciencias naturales y las matemáticas, procurando la conservación y el aumento del potencial del suelo, la producción de alimentos de calidad, el mantenimiento del medio ambiente y la dignificación del hombre rural. El objetivo de la ingeniería agrícola es la generación y aplicación de conocimientos científicos y tecnológic...

  20. A “questão agrária” em Mariátegui

    Directory of Open Access Journals (Sweden)

    Frederico Daia Firmiano

    2012-05-01

    Full Text Available Neste breve artigo temos como objetivo refletir sobre a “questão agrária” no pensamento de José Carlos Mariátegui, sobretudo a partir de sua principal obra, os “Sete ensaios de interpretação da realidade peruana”. Nosso argumento é que o socialista peruano não tratou os problemas da formação social peruana a partir da chave teórica dada pela “questão agrária”, mas a encontrou no curso de uma interpretação marxista, profundamente original e inventiva, sobre esta formação social (desenvolvida ao lado da intensa militância política, identificando o problema indígena ao problema da terra, aos que Amauta conferiu uma alternativa socialista.

  1. La Ingeniería Agrícola en el País

    Directory of Open Access Journals (Sweden)

    Bustamante M. Hellodoro

    1985-12-01

    Full Text Available Es sumamente difícil situar en la historia, el origen de la Ingeniería Agrícola, aunque podría remontarse al propio origen de la tierra, de las plantas y de las aguas. La Ingeniería Agrícola está ocupando un campo de acción que se ha desarrollado a pesar de las limitaciones que le ofrece el mismo desarrollo del país y al escepticismo sin fundamento de algunos pregoneros del pesimismo nacional; le corresponde enfrentar además hoy al cáncer del desempleo y a la falta de oportunidad para demostrar al país que la inversión hecha por el estado en la formación de estos profesionales es productiva.

  2. Sector agrícola y política de competencia

    Directory of Open Access Journals (Sweden)

    Argüello C., Ricardo

    2006-12-01

    Full Text Available Los procesos de integración económica indican que la separación entre políticas comercial y de competencia no sólo es ficticia sino que contradice la realidad de la economía internacional. Este ensayo se discute la relación entre el sector agrícola y la política de competencia en un contexto de liberalización comercial. Sostiene que es necesario aplicar la política de competencia en este sector para incentivar los procesos de cambio tecnológico que requiere el desarrollo agrícola. Y muestra que es indispensable una aplicación rigurosa de la política de competencia que tenga en cuenta las particularidades de la estructura de mercado

  3. AGR-2 Irradiation Test Final As-Run Report, Rev 2

    Energy Technology Data Exchange (ETDEWEB)

    Blaise Collin

    2014-08-01

    This document presents the as-run analysis of the AGR-2 irradiation experiment. AGR-2 is the second of the planned irradiations for the Advanced Gas Reactor (AGR) Fuel Development and Qualification Program. Funding for this program is provided by the U.S. Department of Energy as part of the Very High Temperature Reactor (VHTR) Technical Development Office (TDO) program. The objectives of the AGR-2 experiment are to: (a) Irradiate UCO (uranium oxycarbide) and UO2 (uranium dioxide) fuel produced in a large coater. Fuel attributes are based on results obtained from the AGR-1 test and other project activities. (b) Provide irradiated fuel samples for post-irradiation experiment (PIE) and safety testing. (c) Support the development of an understanding of the relationship between fuel fabrication processes, fuel product properties, and irradiation performance. The primary objective of the test was to irradiate both UCO and UO2 TRISO (tri-structural isotropic) fuel produced from prototypic scale equipment to obtain normal operation and accident condition fuel performance data. The UCO compacts were subjected to a range of burnups and temperatures typical of anticipated prismatic reactor service conditions in three capsules. The test train also includes compacts containing UO2 particles produced independently by the United States, South Africa, and France in three separate capsules. The range of burnups and temperatures in these capsules were typical of anticipated pebble bed reactor service conditions. The results discussed in this report pertain only to U.S. produced fuel. In order to achieve the test objectives, the AGR-2 experiment was irradiated in the B-12 position of the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) for a total irradiation duration of 559.2 effective full power days (EFPD). Irradiation began on June 22, 2010, and ended on October 16, 2013, spanning 12 ATR power cycles and approximately three and a half calendar years. The test

  4. Vancomycin modifies the expression of the agr system in multidrug-resistant Staphylococcus aureus clinical isolates

    Directory of Open Access Journals (Sweden)

    Vicenta eCázares-Domínguez

    2015-05-01

    Full Text Available Staphylococcus aureus is an opportunistic pathogen that colonizes human hosts and causes a wide variety of diseases. Two interacting regulatory systems called agr (accessory gene regulator and sar (staphylococcal accessory regulator are involved in the regulation of virulence factors. The aim of this study was to evaluate the effect of vancomycin on hld and spa gene expression during the exponential and post-exponential growth phases in multidrug resistant (MDR S. aureus. Methods. Antibiotic susceptibility was evaluated by the standard microdilution method. The phylogenetic profile was obtained by pulsed-field gel electrophoresis. Polymorphisms of agr and SCCmec were analyzed by multiplex polymerase chain reaction. The expression levels of hld and spa were analyzed by reverse transcription-PCR. An enzyme-linked immunosorbent assay assay was performed to detect protein A, and biofilm formation was analyzed via crystal violet staining. Results. In total, 60.60% (20/33 of S. aureus clinical isolates were MDR. Half (10/20 of the MDR S. aureus isolates were distributed in subcluster 10, with > 90% similarity among them. In the isolates of this subcluster, a high prevalence (100% for the agrII and the cassette SCCmec II polymorphisms was found. Our data showed significant increases in hld expression during the post-exponential phase in the presence and absence of vancomycin. Significant increases in spa expression, protein A production and biofilm formation were observed during the post-exponential phase when the MDR S. aureus isolates were challenged with vancomycin. Conclusion. The polymorphism agrII, which is associated with nosocomial isolates, was the most prevalent polymorphism in MDR S. aureus. Additionally, under our study conditions, vancomycin modified hld and spa expression in these clinical isolates. Therefore, vancomycin may regulate alternative systems that jointly participate in the regulation of these virulence factors.

  5. Redescubriendo El suelo: Su importancia ecológica y agrícola

    Directory of Open Access Journals (Sweden)

    Noé Manuel Montaño

    2016-10-01

    Full Text Available Redescubriendo el suelo: su importancia ecológica y agrícola es un libro muy completo, actualizado y sin duda será de consulta obligada para quienes hacen investigación edafológica y como material elemental para los cursos de pre- y posgrado de suelo y materias afines, tanto en México como en América Latina.

  6. Status of the NGNP Fuel Experiment AGR-2 Irradiated in the Advanced Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Blaine Grover

    2012-10-01

    The United States Department of Energy’s Next Generation Nuclear Plant (NGNP) Advanced Gas Reactor (AGR) Fuel Development and Qualification Program will be irradiating up to seven separate low enriched uranium (LEU) tri-isotopic (TRISO) particle fuel (in compact form) experiments in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). These irradiations and fuel development are being accomplished to support development of the next generation reactors in the United States, and will be irradiated over the next several years to demonstrate and qualify new TRISO coated particle fuel for use in high temperature gas reactors. The goals of the irradiation experiments are to provide irradiation performance data to support fuel process development, to qualify fuel for normal operating conditions, to support development and validation of fuel performance and fission product transport models and codes, and to provide irradiated fuel and materials for post irradiation examination (PIE) and safety testing. The experiments, which will each consist of at least six separate capsules, will be irradiated in an inert sweep gas atmosphere with individual on-line temperature monitoring and control of each capsule. The sweep gas will also have on-line fission product monitoring on its effluent to track performance of the fuel in each individual capsule during irradiation. The first experiment (designated AGR-1) started irradiation in December 2006 and was completed in November 2009. The second experiment (AGR-2), which utilized the same experiment design as well as control and monitoring systems as AGR-1, started irradiation in June 2010 and is currently scheduled to be completed in April 2013. The design of this experiment and support systems will be briefly discussed, followed by the progress and status of the experiment to date.

  7. Identification of Four New agr Quorum Sensing-Interfering Cyclodepsipeptides from a Marine Photobacterium

    DEFF Research Database (Denmark)

    Kjærulff, Louise; Nielsen, Anita; Månsson, Maria

    2013-01-01

    , including the known pyrrothine antibiotic holomycin and a wide range of peptides, from diketopiperazines to cyclodepsipeptides of 500–900 Da. Purification of components from the pellet fraction led to the isolation and structure elucidation of four new cyclodepsipeptides, ngercheumicin F, G, H, and I....... The ngercheumicins interfered with expression of virulence genes known to be controlled by the agr quorum sensing system of Staphylococcus aureus, although to a lesser extent than the previously described solonamides from the same strain of Photobacterium....

  8. A cidade, um foco de diversidade agrícola no Rio Negro (Amazonas, Brasil?

    Directory of Open Access Journals (Sweden)

    Laure Emperaire

    Full Text Available As regiões do Médio e Alto Rio Negro, apesar de serem isoladas da malha de comunicação terrestre e das frentes de colonização, caracterizam-se por uma articulação cada vez mais forte entre a área florestal, a das comunidades, e a urbana, ou seja, as pequenas cidades ribeirinhas. Esta complementaridade, temporária ou definitiva, se traduz por uma expansão da agricultura periurbana. Propomos uma abordagem comparativa da diversidade agrícola entre o urbano e o florestal. Analisamos as relações entre formas de manejo dos espaços cultivados (superfícies, ciclo de uso e práticas, plantas cultivadas e redes sociais envolvidas no acesso aos recursos fitogenéticos. A análise mostra uma recomposição dos sistemas agrícolas com a permanência de uma alta diversidade agrícola, porém marcada por uma maior vulnerabilidade do sistema em decorrência da diminuição do tempo de pousio e da diminuição da força de trabalho disponível. No contexto urbano, as estratégias tradicionais de manejo dos recursos agrícolas se combinam a um outro objetivo, o do acesso à terra. A análise aponta para a necessidade de uma reflexão sistémica sobre as possíveis formas de conservação deste patrimônio biocultural.

  9. Anterior Gradient 2 (AGR2) Induced Epidermal Growth Factor Receptor (EGFR) Signaling Is Essential for Murine Pancreatitis-Associated Tissue Regeneration

    Science.gov (United States)

    Wodziak, Dariusz; Dong, Aiwen; Basin, Michael F.; Lowe, Anson W.

    2016-01-01

    A recently published study identified Anterior Gradient 2 (AGR2) as a regulator of EGFR signaling by promoting receptor presentation from the endoplasmic reticulum to the cell surface. AGR2 also promotes tissue regeneration in amphibians and fish. Whether AGR2-induced EGFR signaling is essential for tissue regeneration in higher vertebrates was evaluated using a well-characterized murine model for pancreatitis. The impact of AGR2 expression and EGFR signaling on tissue regeneration was evaluated using the caerulein-induced pancreatitis mouse model. EGFR signaling and cell proliferation were examined in the context of the AGR2-/- null mouse or with the EGFR-specific tyrosine kinase inhibitor, AG1478. In addition, the Hippo signaling coactivator YAP1 was evaluated in the context of AGR2 expression during pancreatitis. Pancreatitis-induced AGR2 expression enabled EGFR translocation to the plasma membrane, the initiation of cell signaling, and cell proliferation. EGFR signaling and tissue regeneration were partially inhibited by the tyrosine kinase inhibitor AG1478, but absent in the AGR2-/- null mouse. AG1478-treated and AGR2-/- null mice with pancreatitis died whereas all wild-type controls recovered. YAP1 activation was also dependent on pancreatitis-induced AGR2 expression. AGR2-induced EGFR signaling was essential for tissue regeneration and recovery from pancreatitis. The results establish tissue regeneration as a major function of AGR2-induced EGFR signaling in adult higher vertebrates. Enhanced AGR2 expression and EGFR signaling are also universally present in human pancreatic cancer, which support a linkage between tissue injury, regeneration, and cancer pathogenesis. PMID:27764193

  10. Human oral isolate Lactobacillus fermentum AGR1487 reduces intestinal barrier integrity by increasing the turnover of microtubules in Caco-2 cells.

    Directory of Open Access Journals (Sweden)

    Rachel C Anderson

    Full Text Available Lactobacillus fermentum is found in fermented foods and thought to be harmless. In vivo and clinical studies indicate that some L. fermentum strains have beneficial properties, particularly for gastrointestinal health. However, L. fermentum AGR1487 decreases trans-epithelial electrical resistance (TEER, a measure of intestinal barrier integrity. The hypothesis was that L. fermentum AGR1487 decreases the expression of intestinal cell tight junction genes and proteins, thereby reducing barrier integrity. Transcriptomic and proteomic analyses of Caco-2 cells (model of human intestinal epithelial cells treated with L. fermentum AGR1487 were used to obtain a global view of the effect of the bacterium on intestinal epithelial cells. Specific functional characteristics by which L. fermentum AGR1487 reduces intestinal barrier integrity were examined using confocal microscopy, cell cycle progression and adherence bioassays. The effects of TEER-enhancing L. fermentum AGR1485 were investigated for comparison. L. fermentum AGR1487 did not alter the expression of Caco-2 cell tight junction genes (compared to L. fermentum AGR1485 and tight junction proteins were not able to be detected. However, L. fermentum AGR1487 increased the expression levels of seven tubulin genes and the abundance of three microtubule-associated proteins, which have been linked to tight junction disassembly. Additionally, Caco-2 cells treated with L. fermentum AGR1487 did not have defined and uniform borders of zona occludens 2 around each cell, unlike control or AGR1485 treated cells. L. fermentum AGR1487 cells were required for the negative effect on barrier integrity (bacterial supernatant did not cause a decrease in TEER, suggesting that a physical interaction may be necessary. Increased adherence of L. fermentum AGR1487 to Caco-2 cells (compared to L. fermentum AGR1485 was likely to facilitate this cell-to-cell interaction. These findings illustrate that bacterial strains of the

  11. Desarrollo y perspectiva de la Ingeniería Agrícola

    Directory of Open Access Journals (Sweden)

    Julio E. Ospina Mejía

    2011-02-01

    Full Text Available La Ingeniería Agrícola es la rama de la ingeniería orientada a dar respuesta a los problemas que plantea la agricultura moderna, mediante la aplicación de principios de las ciencias naturales y las matemáticas, procurando la conservación y el aumento del potencial del suelo, la producción de alimentos de calidad, el mantenimiento del medio ambiente y la dignificación del hombre rural. El objetivo de la ingeniería agrícola es la generación y aplicación de conocimientos científicos y tecnológicos de la ingeniería a la producción agropecuaria y otros biosistemas orientados a las áreas de adecuación de tierras, maquinaria agrícola, manejo de recursos hídricos, construcciones rurales, manejo poscosecha y procesamiento de producto agropecuarios, con criterios de sostenibilidad y competitividad.

  12. AGR-1 Compact 5-3-1 Post-Irradiation Examination Results

    Energy Technology Data Exchange (ETDEWEB)

    Paul Demkowicz; Jason Harp; Phil Winston; Scott A. Ploger

    2016-12-01

    The Advanced Gas Reactor (AGR) Fuel Development and Qualification Program was established to perform the requisite research and development on tristructural isotropic (TRISO) coated particle fuel to support deployment of a high-temperature gas-cooled reactor (HTGR). The work continues as part of the Advanced Reactor Technologies (ART) TRISO Fuel program. The overarching program goal is to provide a baseline fuel qualification data set to support licensing and operation of an HTGR. To achieve these goals, the program includes the elements of fuel fabrication, irradiation, post-irradiation examination (PIE) and safety testing, fuel performance, and fission product transport (INL 2015). A series of fuel irradiation experiments is being planned and conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). These experiments will provide data on fuel performance under irradiation, support fuel process development, qualify the fuel for normal operating conditions, provide irradiated fuel for safety testing, and support the development of fuel performance and fission product transport models. The first of these irradiation tests, designated AGR-1, began in the ATR in December 2006 and ended in November 2009. This experiment was conducted primarily to act as a shakedown test of the multicapsule test train design and provide early data on fuel performance for use in fuel fabrication process development. It also provided samples for post-irradiation safety testing, where fission product retention of the fuel at high temperatures will be experimentally measured. The capsule design and details of the AGR-1 experiment have been presented previously.

  13. Perfil profesional del ingeniero agrícola en Costa Rica

    Directory of Open Access Journals (Sweden)

    Herminia Casanueva López

    2005-01-01

    Full Text Available La Ingeniería Agrícola, como carrera y como profesión, existe en Costa Rica desde 1974, por lo que se le considera una profesión joven, sin embargo existe un número ya significativo de profesionales que han ido ubicándose en las distintas áreas propias de su quehacer, por lo que el momento es propicio para realizar una sistematización explícita de las áreas de desempeño profesional, las actividades que se desarrollan en cada área y la proyección de nuevas áreas y actividades para los próximos años. Para la realización de este trabajo, se aplicó una metodología diseñada para “sistemas suaves” y que se caracteriza por ser participativa y flexible por lo que responde metodológicamente a la naturaleza del proyecto. Como producto de la investigación se identificaron siete grandes áreas del quehacer profesional y diez actividades, que se intersecan con las áreas, de esta matriz se genera el perfil profesional actual del Ingeniero Agrícola en Costra Rica y que permite que futuros proyectos lo tomen como base conforme la Ingeniería Agrícola y su práctica profesional evolucionen

  14. Uncertainty Quantification of Calculated Temperatures for the U.S. Capsules in the AGR-2 Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Lybeck, Nancy [Idaho National Lab. (INL), Idaho Falls, ID (United States); Einerson, Jeffrey J. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Pham, Binh T. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hawkes, Grant L. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-03-01

    A series of Advanced Gas Reactor (AGR) irradiation experiments are being conducted within the Advanced Reactor Technology (ART) Fuel Development and Qualification Program. The main objectives of the fuel experimental campaign are to provide the necessary data on fuel performance to support fuel process development, qualify a fuel design and fabrication process for normal operation and accident conditions, and support development and validation of fuel performance and fission product transport models and codes (PLN-3636). The AGR-2 test was inserted in the B-12 position in the Advanced Test Reactor (ATR) core at Idaho National Laboratory (INL) in June 2010 and successfully completed irradiation in October 2013, resulting in irradiation of the TRISO fuel for 559.2 effective full power days (EFPDs) during approximately 3.3 calendar years. The AGR-2 data, including the irradiation data and calculated results, were qualified and stored in the Nuclear Data Management and Analysis System (NDMAS) (Pham and Einerson 2014). To support the U.S. TRISO fuel performance assessment and to provide data for validation of fuel performance and fission product transport models and codes, the daily as-run thermal analysis has been performed separately on each of four AGR-2 U.S. capsules for the entire irradiation as discussed in (Hawkes 2014). The ABAQUS code’s finite element-based thermal model predicts the daily average volume-average fuel temperature and peak fuel temperature in each capsule. This thermal model involves complex physical mechanisms (e.g., graphite holder and fuel compact shrinkage) and properties (e.g., conductivity and density). Therefore, the thermal model predictions are affected by uncertainty in input parameters and by incomplete knowledge of the underlying physics leading to modeling assumptions. Therefore, alongside with the deterministic predictions from a set of input thermal conditions, information about prediction uncertainty is instrumental for the ART

  15. AGR-3/4 Final Data Qualification Report for ATR Cycles 151A through 155B-1

    Energy Technology Data Exchange (ETDEWEB)

    Pham, Binh T. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-03-01

    This report provides the qualification status of experimental data for the entire Advanced Gas Reactor 3/4 (AGR 3/4) fuel irradiation. AGR-3/4 is the third in a series of planned irradiation experiments conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL) for the AGR Fuel Development and Qualification Program, which supports development of the advanced reactor technology under the INL ART Technology Development Office (TDO). The main objective of AGR-3/4 irradiation is to provide a known source of fission products for subsequent transport through compact matrix and structural graphite materials due to the presence of designed-to-fail fuel particles. Full power irradiation of the AGR 3/4 test began on December 14, 2011 (ATR Cycle 151A), and was completed on April 12, 2014 (end of ATR Cycle 155B) after 369.1 effective full power days of irradiation. The AGR-3/4 test was in the reactor core for eight of the ten ATR cycles between 151A and 155B. During the unplanned outage cycle, 153A, the experiment was removed from the ATR northeast flux trap (NEFT) location and stored in the ATR canal. This was to prevent overheating of fuel compacts due to higher than normal ATR power during the subsequent Powered Axial Locator Mechanism cycle, 153B. The AGR 3/4 test was inserted back into the ATR NEFT location during the outage of ATR Cycle 154A on April 26, 2013. Therefore, the AGR-3/4 irradiation data received during these 2 cycles (153A and 153B) are irrelevant and their qualification status isnot included in this report. Additionally, during ATR Cycle 152A the ATR core ran at low power for a short enough duration that the irradiation data are not used for physics and thermal calculations. However, the qualification status of irradiation data for this cycle is still covered in this report. As a result, this report includes data from 8 ATR Cycles: 151A, 151B, 152A, 152B, 154A, 154B, 155A, and 155B, as recorded in the Nuclear Data Management and

  16. Comércio agrícola: o Brasil e a OMC

    Directory of Open Access Journals (Sweden)

    Danielle Annoni

    2004-03-01

    Full Text Available The agricultural and textile sectors, have been the greaters targets of the developed countries protectionism, that possess in common the fact that the amount of man-power used is sufficiently great, it means variation of the products final cost. Therefore, it is not difficult to understand why the most underdeveloped countries are more competitive in the dispute of the world-wide market’s control in these sectors. Thus the importance of the OMC elapses, in the search for the effectiveness of international trade regulation of agricultural goods is an activity that interests the developing countries, what is particularly applicable to Brazil, where the agricultural products answers almost for one third of the exportations.Los sectores agrícolas y textil, han sido los mayores objetivos del proteccionismo de los países desarrollados, que poseen en común la cantidad de mano-de-obra usado y esta energía es suficientemente grande y significa variación del costo final del producto. Por tanto, no es difícil comprender porque cuanto más subdesarrollados los países, más serán competitivos y amenazadores para el conflicto sobre el control del mercado mundial en estos sectores. Así la importancia del OMC transcurre, en la búsqueda para la eficacia de la regulación del comercio internacional de mercancías agrícolas es una, actividad que interesa a los países en vías de desarrollo en su totalidad, lo que es particularmente aplicable al Brasil, donde los productos agrícolas casi contestan para un tercio de las exportaciones.Os setores agrícola e têxtil, têm sido os maiores alvos do protecionismo dos países desenvolvidos, que possuem em comum o fato de que a quantidade de mão-de-obra utilizada é bastante grande o que significa margem de variação do custo final do produto. Portanto, não é difícil entender porque os países quão mais subdesenvolvidos forem mais competitivos e ameaçadores são na disputa pelo controle do mercado

  17. A Revolução Agrária Cubana: conquistas e desafios

    Directory of Open Access Journals (Sweden)

    Juan Valdés Paz

    2011-01-01

    Full Text Available Após o triunfo da Revolução em 1959, iniciou-se uma profunda transformação da sociedade cubana, primeiro política, depois social e, desde muito cedo, agrária. A Revolução Cubana foi a superação da questão agrária originada na etapa republicana e uma opção socialista para o desenvolvimento socioeconômico do país, do qual o desenvolvimento agrário tem sido um eixo fundamental. A superação dessa "questão agrária" do socialismo cubano determina as estratégias em curso e suas metas imediatas. Como parte desse processo, examinamos seis aspectos que caracterizaram seu desenvolvimento; são eles: a estrutura da pose de terra; o uso do solo; a organização agrária; o modelo tecnológico; a economia agrária; e o desenvolvimento da sociedade rural.Con el triunfo de la Revolución en 1959, se inició una profunda transformación de la sociedad cubana, primero política, después social y desde muy tempranamente, agraria. La Revolución Cubana fue la superación de la cuestión agraria originada en la etapa republicana y una opción socialista para el desarrollo socioeconómico del país, del cual el desarrollo agrario ha sido un eje fundamental. La superación de esta "cuestión agraria" del socialismo cubano, determina las estrategias en curso y sus metas inmediatas. Como parte de ese proceso, se examinan seis de los aspectos que caracterizaron su desarrollo, a saber: la estructura de tenencia de la tierra; el uso del suelo; la organización agraria; el modelo tecnológico; la economía agraria; y el desarrollo de la sociedad rural.After the triumph of the revolution in 1959, a profound transformation of Cuban society began - first political, then social and, very early on, agrarian. The Cuban Revolution surmounted the agrarian issue that had originated during the republican phase and embodied a socialist option for socioeconomic development (of which agricultural development was a fundamental part. Cuban socialism's efforts to

  18. AGR-2 Data Qualification Report for ATR Cycles 147A, 148A, 148B, and 149A

    Energy Technology Data Exchange (ETDEWEB)

    Michael L. Abbott; Keith A. Daum

    2011-08-01

    This report presents the data qualification status of fuel irradiation data from the first four reactor cycles (147A, 148A, 148B, and 149A) of the on-going second Advanced Gas Reactor (AGR-2) experiment as recorded in the NGNP Data Management and Analysis System (NDMAS). This includes data received by NDMAS from the period June 22, 2010 through May 21, 2011. AGR-2 is the second in a series of eight planned irradiation experiments for the AGR Fuel Development and Qualification Program, which supports development of the very high temperature gas-cooled reactor (VHTR) under the Next Generation Nuclear Plant (NGNP) Project. Irradiation of the AGR-2 test train is being performed at the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) and is planned for 600 effective full power days (approximately 2.75 calendar years) (PLN-3798). The experiment is intended to demonstrate the performance of UCO (uranium oxycarbide) and UO2 (uranium dioxide) fuel produced in a large coater. Data qualification status of the AGR-1 experiment was reported in INL/EXT-10-17943 (Abbott et al. 2010).

  19. Loss of Anterior Gradient 2 (Agr2) Expression Results in Hyperplasia and Defective Lineage Maturation in the Murine Stomach*

    Science.gov (United States)

    Gupta, Aparna; Wodziak, Dariusz; Tun, May; Bouley, Donna M.; Lowe, Anson W.

    2013-01-01

    Recent studies of epithelial tissues have revealed the presence of tissue-specific stem cells that are able to establish multiple cell lineages within an organ. The stem cells give rise to progenitors that replicate before differentiating into specific cell lineages. The mechanism by which homeostasis is established between proliferating stem or progenitor cells and terminally differentiated cells is unclear. This study demonstrates that Agr2 expression by mucous neck cells in the stomach promotes the differentiation of multiple cell lineages while also inhibiting the proliferation of stem or progenitor cells. When Agr2 expression is absent, gastric mucous neck cells increased in number as does the number of proliferating cells. Agr2 expression loss also resulted in the decline of terminally differentiated cells, which was supplanted by cells that exhibited nuclear SOX9 labeling. Sox9 expression has been associated with progenitor and stem cells. Similar effects of the Agr2 null on cell proliferation in the intestine were also observed. Agr2 consequently serves to maintain the balance between proliferating and differentiated epithelial cells. PMID:23209296

  20. Listeria monocytogenes differential transcriptome analysis reveals temperature-dependent Agr regulation and suggests overlaps with other regulons.

    Science.gov (United States)

    Garmyn, Dominique; Augagneur, Yoann; Gal, Laurent; Vivant, Anne-Laure; Piveteau, Pascal

    2012-01-01

    Listeria monocytogenes is a ubiquitous, opportunistic pathogenic organism. Environmental adaptation requires constant regulation of gene expression. Among transcriptional regulators, AgrA is part of an auto-induction system. Temperature is an environmental cue critical for in vivo adaptation. In order to investigate how temperature may affect AgrA-dependent transcription, we compared the transcriptomes of the parental strain L. monocytogenes EGD-e and its ΔagrA mutant at the saprophytic temperature of 25°C and in vivo temperature of 37°C. Variations of transcriptome were higher at 37°C than at 25°C. Results suggested that AgrA may be involved in the regulation of nitrogen transport, amino acids, purine and pyrimidine biosynthetic pathways and phage-related functions. Deregulations resulted in a growth advantage at 37°C, but affected salt tolerance. Finally, our results suggest overlaps with PrfA, σB, σH and CodY regulons. These overlaps may suggest that through AgrA, Listeria monocytogenes integrates information on its biotic environment.

  1. Programa computacional para calcular a potência requerida de máquinas e implementos agrícolas

    Directory of Open Access Journals (Sweden)

    Pablo Pereira Corrêa Klaver

    2013-12-01

    Full Text Available O uso de programas computacionais no setor agrícola permite atingir objetivos específicos na área. Dentre esses, um dos mais complexos é a seleção adequada de máquinas e implementos agrícolas visando à otimização de operações agrícolas, devido, principalmente, à grande variedade de equipamentos existentes no mercado e a gama de tarefas e situações de trabalho que estas são submetidas no campo. O objetivo deste trabalho foi desenvolver um programa computacional para calcular a potência requerida de máquinas e implementos agrícolas normalmente utilizados na condução de operações de campo, desde o preparo do solo até as operações de implantação de culturas. Desenvolvido em linguagem PHP, o programa computacional baseia-se na norma ASAE D497.4 - Agricultural Machinery Management Data como referência para desenvolvimento de cálculos. A partir do programa desenvolvido, tornou-se possível a execução de tarefas para cálculos de avaliação da demanda de potência de máquinas e implementos agrícolas de forma simplificada pela internet.

  2. Sistemas de producción agrícola sostenible

    Directory of Open Access Journals (Sweden)

    Róger Martínez Castillo

    2009-01-01

    Full Text Available El desarrollo sostenible se fundamenta en principios éticos, como el respeto y armonía con la naturaleza; valores políticos, como la democracia participativa y equidad social; y normas morales, como racionalidad ambiental. El desarrollo sostenible es igualitario, descentralizado y autogestionario, capaz de satisfacer las necesidades básicas de la población, respetando la diversidad cultural y mejorando la calidad de vida. La agricultura y el desarrollo sostenible se refieren a la necesidad de minimizar la degradación de la tierra agrícola, maximizando a su vez la producción. Este considera el conjunto de las actividades agrícolas, como el manejo de suelos y aguas,el manejo de cultivos y la conservación de la biodiversidad; considerando a su vez el suministro de alimentos y materias primas. La sostenibilidad de los sistemas de producción agrícola se refiere a la capacidad del sistema para mantener su productividad a pesar de las perturbaciones económicas y naturales, externas o internas. La sostenibilidad es función de las características naturales del sistema y las presiones e intervenciones que sufre, así como aquellas intervenciones sociales, económicas y técnicas que se hacen para contrarrestar presiones negativas; destacándose la resiliencia del sistema.

  3. AGR-1 Compact 1-3-1 Post-Irradiation Examination Results

    Energy Technology Data Exchange (ETDEWEB)

    Demkowicz, Paul Andrew [Idaho National Laboratory

    2016-12-01

    The Advanced Gas Reactor (AGR) Fuel Development and Qualification Program was established to perform the requisite research and development on tristructural isotropic (TRISO) coated particle fuel to support deployment of a high-temperature gas-cooled reactor (HTGR). The work continues as part of the Advanced Reactor Technologies (ART) TRISO Fuel program. The overarching program goal is to provide a baseline fuel qualification data set to support licensing and operation of an HTGR. To achieve these goals, the program includes the elements of fuel fabrication, irradiation, post-irradiation examination (PIE) and safety testing, fuel performance modeling, and fission product transport (INL 2015). A series of fuel irradiation experiments is being planned and conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). These experiments will provide data on fuel performance under irradiation, support fuel process development, qualify the fuel for normal operating conditions, provide irradiated fuel for safety testing, and support the development of fuel performance and fission product transport models. The first of these irradiation tests, designated AGR-1, began in the ATR in December 2006 and ended in November 2009. This experiment was conducted primarily to act as a shakedown test of the multicapsule test train design and provide early data on fuel performance for use in fuel fabrication process development. It also provided samples for post-irradiation safety testing, where fission product retention of the fuel at high temperatures will be experimentally measured. The capsule design and details of the AGR-1 experiment have been presented previously (Grover, Petti, and Maki 2010, Maki 2009).

  4. Sostenibilidad de sistemas agrícolas Sustainability of farming systems

    Directory of Open Access Journals (Sweden)

    Leiva Fabio R.

    1998-12-01

    Full Text Available Las actividades agrícolas pueden tener impactos negativos sobre el ambiente, con efectos dentro y fuera de los predios. El presente artículo pretende contribuir al avance de la agricultura sostenible con énfasis en países en vías de desarrollo. Se revisan y analizan los conceptos de sostenibilidad y agricultura sostenible, incluyendo los diferentes puntos de vista en el debate sobre sostenibilidad'. El artículo examina los impactos ambientales debidos a las actividades agrícolas, destacando la importancia de fortalecer la investigación, con publicación de resultados, sobre la relación agricultura y medio ambiente. La complejidad de los factores que determinan la sostenibilidad agrícola exige una concepción de sistemas, integradora, participativa y holística. El uso de indicadores tiene un gran potencial en la evaluación de la sostenibilidad de sistemas productivos. La práctica de agricultura sostenible requiere tener en cuenta las condiciones ambientales, sociales y económicas en las cuales
    se desenvuelve la agricultura.Farming activities have the potential to affect the farming system itself and the offfarm environment. This paper attempts to contribute to the development of sustainable agriculture with emphasis in developing countries. The concepts of sustainability and sustainable agriculture are reviewed and discussed, including the different viewpoints in the sustainability debate. Environmental impacts due to farming activities are examined emphasising the need of promoting further research and publication of findings on the links between environment and agriculture. The complexity of the factors that determine farming sustainability requires
    a systematic, holistic, participative and integrated approach. Indicators are likely to contribute to the development of sustainable farming systems. Understanding environmental, social and economic circumstances is required to promote sustainability.

  5. Unidades integrales de servicios técnicos de maquinaria agrícola

    OpenAIRE

    José Suárez; Arcadio Ríos; Evelio Linares

    2011-01-01

    En cada municipio cubano se inició la creación de centros encargados de prestar servicios de mecanización agrícola y asistencia técnica a los productores. Para esto deben disponer de tractores, cosechadoras y otras máquinas e implementos propios, así como de talleres para la reparación y mantenimiento. Cada uno de estos centros será una Unidad Integral de Servicios Técnicos (UIST) con el carácter de Unidad Empresarial de Base (UEB) subordinada a la Empresa Agropecuaria Municipal. Para constit...

  6. Escuelas de campo y adopción de ecotecnia agrícola

    OpenAIRE

    2008-01-01

    Las Escuelas de Campo (EC) son un método de extensión participativo que permite desarrollar capacidades analíticas, pensamiento crítico y, creatividad. La investigación se realizó en la región Mazateca de Oaxaca, la cual se caracteriza por su alto rezago tecnológico, porque resulta de relevancia científica, social y ecológica conocer, en este contexto, los alcances de metodologías alternativas de extensionismo sobre la adopción de ecotecnias agrícolas. Nuestro objetivo fue conocer la...

  7. A crise de identidade das cooperativas agrárias na França

    OpenAIRE

    Vargas-Prieto, Amanda

    2014-01-01

    El contexto evolutivo del sector agrícola en Francia llevó a las cooperativas agrarias a crear grupos de empresas que combinan las cooperativas tradicionales —encargadas del proceso de producción— y las filiales, encargadas de agregar valor a la producción. En este artículo se presenta la especificidad de los grupos cooperativos agrarios en Francia. La nueva estructura cooperativa lleva a asociar el modo de gobernanza asociativo de la estructura tradicional y el modo de gobernanza accionarial...

  8. Manejo y uso de biosólidos en suelos agrícolas

    OpenAIRE

    Robledo Santoyo, Edmundo

    2012-01-01

    Como subproducto del tratamiento de las aguas residuales de la ciudad de Aguascalientes, Ags., en la Planta de Tratamiento “El Niágara”, se generan diariamente de 150 a 170 m3 de biosólidos. Estos materiales son aplicados a suelos agrícolas de áreas cercanas a la planta, sin regulación alguna, por lo que se han obtenido buenos resultados o causado quemaduras en plántulas o endurecimiento de suelos. El objetivo de este proyecto fue generar estrategias para la disposición y aprovechamiento de l...

  9. Biorremediación de un suelo agrícola impactado con aceite residual automotriz

    OpenAIRE

    Pasaye Anaya, Lizbeth

    2011-01-01

    El aceite residual automotriz (ARA) derivado del uso de automotores es una mezcla de hidrocarburos (HC) alifáticos, aromáticos y otros que en el suelo impide la actividad microbiana para el reciclaje de elementos esenciales para la vida. El objetivo de este trabajo fue analizar la biorremediación (BR) por bioestimulación (BS) de un suelo agrícola impactado con ARA. Para ello, el suelo contaminado con la mezcla de HC se biorremedió por BS con una solución mineral (SM), lombricomposta (LC) y ab...

  10. Comportamiento adsortivo-desortivo del lindano en un suelo agrícola

    OpenAIRE

    Ireri V. Robles-González; Elvira Ríos-Leal; Juvencio Galíndez-Mayer; Sergio Caffarel-Méndez; Josefina Barrera-Cortés; Fernando J. Esparza-García; Poggi-Varaldo, Héctor M

    2006-01-01

    El objetivo de este trabajo fue estudiar el comportamiento adsortivo-desortivo del pesticida lindano en un suelo agrícola con importante contenido de materia orgánica, utilizando el coeficiente de histéresis diferencial (CHPoggi). Además se obtuvo una expresión analítica simple del CHPoggi para el caso mixto, cuando la isoterma de adsorción sigue el modelo lineal y la isoterma de desorción sigue el modelo de Langmuir. Se obtuvo una isoterma de adsorción lineal, q= 3,91·C y una isoterma de des...

  11. Readiness Review of BWXT for Fabrication of AGR-5/6/7 TRISO Particles

    Energy Technology Data Exchange (ETDEWEB)

    Marshall, Douglas William [Idaho National Lab. (INL), Idaho Falls, ID (United States); Sharp, Michelle Tracy [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-02-01

    INL readiness review assessment of BWXT readiness to commence fabrication of low-enriched TRISO coated fuel particles for the AGR-5/6/7 irradiation experiments. BWXT self-identified equipment issues preventing operation. INL identified two findings. The first was that disposition codes had not been assigned and documented on BWXT forms to ensure that off-specification materials could not be used in the fabrication of TRISO particles. The second was that chemical purity specifications were not reliably passed on to chemical suppliers, which resulted in the receipt of one acetylene cylinder with suspect impurity levels.

  12. X-ray Analysis of Defects and Anomalies in AGR-5/6/7 TRISO Particles

    Energy Technology Data Exchange (ETDEWEB)

    Helmreich, Grant W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hunn, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Skitt, Darren J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dyer, John A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Schumacher, Austin T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-06-01

    Coated particle fuel batches J52O-16-93164, 93165, 93166, 93168, 93169, 93170, and 93172 were produced by Babcock and Wilcox Technologies (BWXT) for possible selection as fuel for the Advanced Gas Reactor Fuel Development and Qualification (AGR) Program’s AGR-5/6/7 irradiation test in the Idaho National Laboratory (INL) Advanced Test Reactor (ATR), or may be used for other tests. Each batch was coated in a 150-mm-diameter production-scale fluidized-bed chemical vapor deposition (CVD) furnace. Tristructural isotropic (TRISO) coatings were deposited on 425-μm-nominal-diameter spherical kernels from BWXT lot J52R-16-69317 containing a mixture of 15.4%-enriched uranium carbide and uranium oxide (UCO), with the exception of Batch 93164, which used similar kernels from BWXT lot J52L-16-69316. The TRISO-coatings consisted of a ~50% dense carbon buffer layer with 100-μmnominal thickness, a dense inner pyrolytic carbon (IPyC) layer with 40-μm-nominal thickness, a silicon carbide (SiC) layer with 35-μm-nominal thickness, and a dense outer pyrolytic carbon (OPyC) layer with 40-μm-nominal thickness. Each coated particle batch was sieved to upgrade the particles by removing over-sized and under-sized material, and the upgraded batch was designated by appending the letter A to the end of the batch number (e.g., 93164A). Secondary upgrading by sieving was performed on the upgraded batches to remove specific anomalies identified during analysis for Defective IPyC, and the upgraded batches were designated by appending the letter B to the end of the batch number (e.g., 93165B). Following this secondary upgrading, coated particle composite J52R-16-98005 was produced by BWXT as fuel for the AGR Program’s AGR-5/6/7 irradiation test in the INL ATR. This composite was comprised of coated particle fuel batches J52O-16-93165B, 93168B, 93169B, and 93170B.

  13. Nox2 modification of LDL is essential for optimal apolipoprotein B-mediated control of agr type III Staphylococcus aureus quorum-sensing.

    Directory of Open Access Journals (Sweden)

    Pamela R Hall

    2013-02-01

    Full Text Available Staphylococcus aureus contains an autoinducing quorum-sensing system encoded within the agr operon that coordinates expression of virulence genes required for invasive infection. Allelic variation within agr has generated four agr specific groups, agr I-IV, each of which secretes a distinct autoinducing peptide pheromone (AIP1-4 that drives agr signaling. Because agr signaling mediates a phenotypic change in this pathogen from an adherent colonizing phenotype to one associated with considerable tissue injury and invasiveness, we postulated that a significant contribution to host defense against tissue damaging and invasive infections could be provided by innate immune mechanisms that antagonize agr signaling. We determined whether two host defense factors that inhibit AIP1-induced agrI signaling, Nox2 and apolipoprotein B (apoB, also contribute to innate control of AIP3-induced agrIII signaling. We hypothesized that apoB and Nox2 would function differently against AIP3, which differs from AIP1 in amino acid sequence and length. Here we show that unlike AIP1, AIP3 is resistant to direct oxidant inactivation by Nox2 characteristic ROS. Rather, the contribution of Nox2 to defense against agrIII signaling is through oxidation of LDL. ApoB in the context of oxLDL, and not LDL, provides optimal host defense against S. aureus agrIII infection by binding the secreted signaling peptide, AIP3, and preventing expression of the agr-driven virulence factors which mediate invasive infection. ApoB within the context of oxLDL also binds AIP 1-4 and oxLDL antagonizes agr signaling by all four agr alleles. Our results suggest that Nox2-mediated oxidation of LDL facilitates a conformational change in apoB to one sufficient for binding and sequestration of all four AIPs, demonstrating the interdependence of apoB and Nox2 in host defense against agr signaling. These data reveal a novel role for oxLDL in host defense against S. aureus quorum-sensing signaling.

  14. The Relationship Between Antibiotic Resistance and Agr Type in Methicillin-Resistant Staphylococcus aureus (MRSA Isolated From Burn Wound of Hospitalized Patient in Tehran

    Directory of Open Access Journals (Sweden)

    Mohammad Sadegh Vaziri

    2015-12-01

    Full Text Available Introduction: Staphylococcus aureus is the major cause of hospital and community-acquired infections. This bacterium possesses an accessory gene regulator (agr that plays role in colonization, expression of virulence factors and antibiotic resistance. It’s four major polypeptide with variable sequences lead to at least four agr type in S. aureus.The aim of this study was to determine the relationship between the antibiogram patterns with agr type of clinical S. aureus.Methods: Detection of methicillin-resistant Staphylococcus aureus (MRSA from burn wounds was performed by phenotypic and genotypic profiles. The antibiotics resistance pattern was determined by disk agar diffusion (Tigecycline (TGC, Ciprofloxacin(CIP, Erythromycin(E, Cloxacillin(CX, Clindamycin(CD, Imipenem(IMI, Co-trimoxazole(SXT, Kanamycin(K, Teicoplanin(TEC, Gentamicin(GM, Mupirocin(MUP, Ceftriaxone (CTR. The agr typing by PCR-RFLP method using the Restriction endonuclease ScaI was performed and spss19 was used for data analysis.Results: The total of 76 MRSA isolates was studied. The agr type distribution was 75.6% Type I, 8.2% Type II, 5.4% Type III, 10.8% type IV. The most antibiotics resistant agr type belongs to the type I. There was no significance relationship between every agr type and antibiotics but only a statistically significant association exist between CX, E, CTR, SXT, GM, CIP antibiotics and all agr types (P<0.05.Conclusion: There was no significance relationship between every agr type and antibiotics but significant relationship observed between resistance to some antibiotics with all agr types could be related to the number and source of isolated bacteria or extra use of these antibiotics. By considering that agr locus belongs to upstream genes so it may use the Quorum Sensing (QS system to induce the most drug resistance.

  15. ELECTRON PROBE MICROANALYSIS OF IRRADIATED AND 1600°C SAFETY-TESTED AGR-1 TRISO FUEL PARTICLES WITH LOW AND HIGH RETAINED 110MAG

    Energy Technology Data Exchange (ETDEWEB)

    Wright, Karen E.; van Rooyen, Isabella J.

    2016-11-01

    AGR-1 fuel Compact 4-3-3 achieved 18.63% FIMA and was exposed subsequently to a safety test at 1600°C. Two particles, AGR1-433-003 and AGR1-433-007, with measured-to-calculated 110mAg inventories of <22% and 100%, respectively, were selected for comparative electron microprobe analysis to determine whether the distribution or abundance of fission products differed proximally and distally from the deformed kernel in AGR1-433-003, and how this compared to fission product distribution in AGR1-433-007. On the deformed side of AGR1-433-003, Xe, Cs, I, Eu, Sr, and Te concentrations in the kernel buffer interface near the protruded kernel were up to six times higher than on the opposite, non-deformed side. At the SiC-inner pyrolytic carbon (IPyC) interface proximal to the deformed kernel, Pd and Ag concentrations were 1.2 wt% and 0.04 wt% respectively, whereas on the SiC-IPyC interface distal from the kernel deformation those elements measured 0.4 and 0.01 wt%, respectively. Palladium and Ag concentrations at the SiC-IPyC interface of AGR1-433-007 were 2.05 and 0.05 wt.%, respectively. Rare earth element concentrations at the SiC-IPyC interface of AGR1-433-007 were a factor of ten higher than at the SiC-IPyC interfaces measured in particle AGR1-433-003. Palladium permeated the SiC layer of AGR1-433-007 and the non-deformed SiC layer of AGR1-433-003.

  16. Trabajadores agrícolas migrantes en Baja California. Vinculación con la migración internacional

    Directory of Open Access Journals (Sweden)

    Ma. Eugenia Anguiano Téllez

    1989-09-01

    Full Text Available En este ensayo los jornaleros agrícolas migrantes son clasificados en dos estratos: el primero, considera la migración internacional, es decir, aquéllos que se internan en Estados Unidos con el propósito de conseguir empleo; y el segundo, corresponde a la migración interna de los trabajadores agrícolas que permanecen en Baja California para laborar en los valles de Mexicali y San Quintín.En este trabajo se señalan las diferencias entre estos dos estratos, tanto de carácter económico como en los niveles de educación; asimismo, se comparan las características de los jornaleros agrícolas migrantes que cruzan a Estados Unidos por Mexicali y por Tijuana, según su actividad económica de procedencia y su expectativa de empleo en los Estados Unidos.

  17. Unidades integrales de servicios técnicos de maquinaria agrícola

    Directory of Open Access Journals (Sweden)

    José Suárez

    2011-01-01

    Full Text Available En cada municipio cubano se inició la creación de centros encargados de prestar servicios de mecanización agrícola y asistencia técnica a los productores. Para esto deben disponer de tractores, cosechadoras y otras máquinas e implementos propios, así como de talleres para la reparación y mantenimiento. Cada uno de estos centros será una Unidad Integral de Servicios Técnicos (UIST con el carácter de Unidad Empresarial de Base (UEB subordinada a la Empresa Agropecuaria Municipal. Para constituir estas Unidades fue necesario realizar un estudio de la disponibilidad de talleres, equipamiento, maquinaria y personal de mecanización en las empresas agrícolas y otras entidades productivas de todos los municipios del país, pues ellos constituirán el núcleo fundamental del nuevo sistema. Se ha conformado la propuesta del esquema de funcionamiento de las Unidades, especialmente en lo que respecta a áreas, funciones, equipamiento, modelo de gestión, contratación de servicios, planificación, organización, control, relaciones con otras entidades productivas y de dirección, etc. Estas Unidades se están creando en municipios seleccionados, con vistas a evaluar los resultados, y, teniendo en cuenta las experiencias obtenidas, conformar el programa para extender el sistema a todo el país.

  18. Post-irradiation Examination of the AGR-1 Experiment: Plans and Preliminary Results

    Energy Technology Data Exchange (ETDEWEB)

    Paul Demkowicz

    2001-10-01

    Abstract – The AGR-1 irradiation experiment contains seventy-two individual cylindrical fuel compacts (25 mm long x 12.5 mm diameter) each containing approximately 4100 TRISO-coated uranium oxycarbide fuel particles. The experiment accumulated 620 effective full power days in the Advanced Test Reactor at the Idaho National Laboratory with peak burnups exceeding 19% FIMA. An extensive post-irradiation examination campaign will be performed on the AGR-1 fuel in order to characterize the irradiated fuel properties, assess the in-pile fuel performance in terms of coating integrity and fission metals release, and determine the fission product retention behavior during high temperature accident testing. PIE experiments will include dimensional measurements of fuel and irradiated graphite, burnup measurements, assessment of fission metals release during irradiation, evaluation of coating integrity using the leach-burn-leach technique, microscopic examination of kernel and coating microstructures, and accident testing of the fuel in helium at temperatures up to 1800°C. Activities completed to date include opening of the irradiated capsules, measurement of fuel dimensions, and gamma spectrometry of selected fuel compacts.

  19. Existe convergência espacial da produtividade agrícola no Brasil?

    Directory of Open Access Journals (Sweden)

    Eduardo Simões de Almeida

    2008-03-01

    Full Text Available Este trabalho analisa a convergência espacial da produtividade agrícola da terra para as microrregiões brasileiras entre o período de 1991 a 2003. Tal análise avalia se há evidências para a existência de convergência beta da produtividade agrícola, controlando-se explicitamente para efeitos espaciais. Para tanto, conduziu-se preliminarmente uma análise exploratória de dados espaciais, que detectou a presença de autocorrelação espacial para a produtividade da terra. Numa etapa posterior, desenvolveram-se modelos econométricos espaciais para a análise da convergência.This work analyzes the convergence of land productivity for Brazilian regions from 1991 to 2003. It evaluates if there is or not beta convergence of the agricultural productivity, controlling explicitly for spatial effects. To do so, an exploratory spatial data analysis was previously implemented and the presence of spatial autocorrelation for the land productivity was detected. In addition, spatial econometric models were developed for the convergence analysis.

  20. Validation of the Physics Analysis used to Characterize the AGR-1 TRISO Fuel Irradiation Test

    Energy Technology Data Exchange (ETDEWEB)

    Sterbentz, James W.; Harp, Jason M.; Demkowicz, Paul A.; Hawkes, Grant L.; Chang, Gray S.

    2015-05-01

    The results of a detailed physics depletion calculation used to characterize the AGR-1 TRISO-coated particle fuel test irradiated in the Advanced Test Reactor (ATR) at the Idaho National Laboratory are compared to measured data for the purpose of validation. The particle fuel was irradiated for 13 ATR power cycles over three calendar years. The physics analysis predicts compact burnups ranging from 11.30-19.56% FIMA and cumulative neutron fast fluence from 2.21?4.39E+25 n/m2 under simulated high-temperature gas-cooled reactor conditions in the ATR. The physics depletion calculation can provide a full characterization of all 72 irradiated TRISO-coated particle compacts during and post-irradiation, so validation of this physics calculation was a top priority. The validation of the physics analysis was done through comparisons with available measured experimental data which included: 1) high-resolution gamma scans for compact activity and burnup, 2) mass spectrometry for compact burnup, 3) flux wires for cumulative fast fluence, and 4) mass spectrometry for individual actinide and fission product concentrations. The measured data are generally in very good agreement with the calculated results, and therefore provide an adequate validation of the physics analysis and the results used to characterize the irradiated AGR-1 TRISO fuel.

  1. Mercado de derechos de agua para uso agrícola en el noroeste de México

    OpenAIRE

    Lorenzo Fidel Cota-Verdugo; Alfredo Beltrán-Morales; Enrique Troyo-Diéguez; José Luís García-Hernández; Luis Felipe Beltrán-Morales; Víctor Ángel Hernández-Trejo; Alfredo Ortega-Rubio; Agustín Navarro Bravo

    2013-01-01

    El estado de Baja California sur, es una zona árida y la provisión de agua para la agricultura y demás usos, se sustenta en acuíferos subterráneos. La legislación en materia de agua se ha modificado acorde al problema evidente del crecimiento en el consumo, especialmente para uso agrícola, incluyendo la figura de mercados de derechos de agua. El objetivo de este trabajo, es buscar mecanismos de mercado que legalicen las transacciones de agua entre usuarios agrícolas, proponer la implementaci...

  2. Estructura económica nacional: breve análisis del sector agrícola ecuatoriano

    OpenAIRE

    Jorge González-Sarango; Darwin Ordóñez-Iturralde

    2015-01-01

    La estructura económica del Ecuador se ha basado, tradicionalmente, en el sector agrícola, el cual enfrenta un panorama económico mundial desalentador. El actual, pero bajo, precio del petróleo, podría incentivar a los importadores de materias primas, pero a la vez complicaría la situación de los exportadores de productos agrícolas, especialmente en economías, como la ecuatoriana, que no cuentan con estrategias de mejora de los niveles de productividad ante el régimen de tipo de cambio flexib...

  3. Evaluación de residuos agrícolas para la producción del hongo Pleurotus ostreatus

    OpenAIRE

    María Bernarda Ruilova Cueva; Aldo Hernández Monzón

    2014-01-01

    Se caracterizaron los residuos agrícolas de la provincia de Bolívar, Ecuador, desde el punto de vista de su composición físico-química para su empleo en el cultivo del hongo Pleurotus ostreatus. Los residuos agrícolas utilizados fueron: maíz, trigo, cebada, lenteja, bagazo de caña de azúcar y cascarilla de arroz. Se realizaron análisis de: humedad, cenizas, extracto etéreo, proteína, fibra, extracto libre de nitrógeno, fibra detergente neutra, fibra detergente ácida, lignina, celulosa, hemice...

  4. Green fluorescent protein (GFP)-based overexpression screening and characterization of AgrC, a Receptor protein of quorum sensing in Staphylococcus aureus.

    Science.gov (United States)

    Wang, Lina; Quan, Chunshan; Liu, Baoquan; Xu, Yongbin; Zhao, Pengchao; Xiong, Wen; Fan, Shengdi

    2013-09-06

    Staphylococcus aureus AgrC is an important component of the agr quorum-sensing system. AgrC is a membrane-embedded histidine kinase that is thought to act as a sensor for the recognition of environmental signals and the transduction of signals into the cytoplasm. However, the difficulty of expressing and purifying functional membrane proteins has drastically hindered in-depth understanding of the molecular structures and physiological functions of these proteins. Here, we describe the high-yield expression and purification of AgrC, and analyze its kinase activity. A C-terminal green fluorescent protein (GFP) fusion to AgrC served as a reporter for monitoring protein expression levels in real time. Protein expression levels were analyzed by the microscopic assessment of the whole-cell fluorescence. The expressed AgrC-GFP protein with a C-terminal His-tagged was purified using immobilized metal affinity chromatography (IMAC) and size exclusion chromatography (SEC) at yields of ≥ 10 mg/L, following optimization. We also assessed the effects of different detergents on membrane solubilization and AgrC kinase activity, and polyoxyethylene-(23)-lauryl-ether (Brij-35) was identified as the most suitable detergent. Furthermore, the secondary structural stability of purified AgrC was analyzed using circular dichroism (CD) spectroscopy. This study may serve as a general guide for improving the yields of other membrane protein preparations and selecting the appropriate detergent to stabilize membrane proteins for biophysical and biochemical analyses.

  5. Staphylococcal superantigen-like genes, ssl5 and ssl8, are positively regulated by Sae and negatively by Agr in the Newman strain.

    Science.gov (United States)

    Pantrangi, Madhulatha; Singh, Vineet K; Wolz, Christiane; Shukla, Sanjay K

    2010-07-01

    Some of the staphylococcal superantigen-like (SSL) proteins SSL5, SSL7, SSL9, and SSL11 act as immunomodulatory proteins in Staphylococcus aureus. However, little is known about their regulatory mechanisms. We determined the expression levels of ssl5 and ssl8 in seven clinically important S. aureus strains and their regulatory mechanisms in the Newman strain, which had the highest ssl5 and ssl8 expression. Independent comparisons of ssl5 or ssl8 coding and upstream sequences in these strains identified multiple haplotypes that did not correlate with the differential expression of ssl5 and ssl8, suggesting the role of additional regulatory elements. Using knockout mutant strains of known S. aureus global regulators such as Agr, Sae, and SigB in the Newman strain, we showed that both ssl5 and ssl8 were induced by Sae and repressed by Agr, suggesting that Sae and Agr are the positive and the negative regulators, respectively, of these two ssl genes. Moreover, we observed upregulation of sae in the agr mutant and upregulation of agr in the sae mutant compared with the isogenic Newman strain, suggesting that the Agr and Sae may be inhibiting each other. The SigB mutation did not affect ssl5 and ssl8 expression, but they were downregulated in the agr/sigB double mutant, indicating that SigB probably acts synergistically with Agr in their upregulation.

  6. Green Fluorescent Protein (GFP-Based Overexpression Screening and Characterization of AgrC, a Receptor Protein of Quorum Sensing in Staphylococcus aureus

    Directory of Open Access Journals (Sweden)

    Shengdi Fan

    2013-09-01

    Full Text Available Staphylococcus aureus AgrC is an important component of the agr quorum-sensing system. AgrC is a membrane-embedded histidine kinase that is thought to act as a sensor for the recognition of environmental signals and the transduction of signals into the cytoplasm. However, the difficulty of expressing and purifying functional membrane proteins has drastically hindered in-depth understanding of the molecular structures and physiological functions of these proteins. Here, we describe the high-yield expression and purification of AgrC, and analyze its kinase activity. A C-terminal green fluorescent protein (GFP fusion to AgrC served as a reporter for monitoring protein expression levels in real time. Protein expression levels were analyzed by the microscopic assessment of the whole-cell fluorescence. The expressed AgrC-GFP protein with a C-terminal His-tagged was purified using immobilized metal affinity chromatography (IMAC and size exclusion chromatography (SEC at yields of ≥10 mg/L, following optimization. We also assessed the effects of different detergents on membrane solubilization and AgrC kinase activity, and polyoxyethylene-(23-lauryl-ether (Brij-35 was identified as the most suitable detergent. Furthermore, the secondary structural stability of purified AgrC was analyzed using circular dichroism (CD spectroscopy. This study may serve as a general guide for improving the yields of other membrane protein preparations and selecting the appropriate detergent to stabilize membrane proteins for biophysical and biochemical analyses.

  7. An agr-like two-component regulatory system in Lactobacillus plantarum is involved in production of a novel cyclic peptide and regulation of adherence

    NARCIS (Netherlands)

    Sturme, M.H.J.; Nakayama, J.; Molenaar, D.; Murakami, Y.; Kunugi, R.; Fujii, T.; Vaughan, E.E.; Kleerebezem, M.; Vos, de W.M.

    2005-01-01

    We have analyzed a locus on the annotated Lactobacillus plantarum WCFS1 genome that showed homology to the staphylococcal agr quorum-sensing system and designated it lam for Lactobacillus agr-like module. Production of the lamBDCA transcript was shown to be growth phase dependent. Analysis of a resp

  8. CO{sub 2} direct cycles suitable for AGR type reactors; Cycles directs de gaz carbonique applicables aux reacteurs du genre AGR

    Energy Technology Data Exchange (ETDEWEB)

    Maillet, E. [Commissariat a l' Energie Atomique. Centre d' Etudes Nucleaires de Saclay, 91 - Gif-sur-Yvette (France)

    1967-10-01

    The perspectives given by the gas turbines under pressure, to build simple nuclear power plants and acieving significantly high yield, are specified. The CO{sub 2} is characterised by by good efficiency under moderate temperature (500 to 750 Celsius degrees), compactness and the simpleness of machines and the safe exploitation (supply, storage, relief cooling, thermosyphon). The revision of thermal properties of the CO{sub 2} and loss elements show that several direct cycles would fit in particular to the AGR type reactors. Cycles that would diverge a little from classical models and able to lead to power and heat generation can lead by simple means to the best results. Several satisfying solutions present for the starting up, the power regulation and the stopping. The nuclear power plant components and the functioning safety are equally considered in the present report. The conclusions stimulate the studies and realizations of carbon dioxide gas turbines in when approprite. [French] Les perspectives offertes par la turbine a gaz sous pression, pour construire des centrales nucleaires simples et de rendement progressivement eleve, se precisent actuellement. le CO{sub 2} se distingue par sa bonne efficacite a temperature moderee (500 a 750 degres celsius), la compacite et la simplicite des machines, et la surete qu'il apporte a l'exploitation ( approvisionnement, stockage, refroidissement de secours, thermosiphon). La revision des proprietes thermophysiques du CO{sub 2} et des elements de pertes montre que divers cycles directs conviendraient en particulier aux reacteurs agr ou derives. Des cycles s'ecartant peu des modeles classiques, et se pretant ulterieurement a la production simultanee d'electricite et de chaleur, peuvent conduire par des moyens simples aux meilleurs resultats d'ensemble. Plusieurs solutions satisfaisantes se presentent pour le demarrage, le reglage de la puissance et l'arret. Les composants de la centrale et la

  9. Una aproximación a las características actuales de la mano de obra agrícola en el valle de Mexicali

    Directory of Open Access Journals (Sweden)

    José Ascención Moreno Mena

    1994-07-01

    Full Text Available Este trabajo aborda, de manera sintética, algunas características de la estructura agraria, así como de productores agrícolas del valle de Mexicali. Se presenta un acercamiento a las condiciones en que se desarrolla la mano de obra actual en el sector agrícola del municipio de Mexicali. Para ello se toma como base información primaria obtenida de dos encuestas realizadas durante el periodo 1991-1994; laprimera producto de un muestreo no aleatorio por cuotas aplicada a 150 trabajadores agrícolas del algodón; y la segunda de carácter aleatoria aplicada en 499 viviendas de trabajadores agrícolas en el valle de Mexicali por el Instituto de investigaciones Sociales de la Universidad Autónoma de Baja California y el Programa Nacional de Solidaridad con Jornaleros Agrícolas.

  10. Determination of the Quantity of I-135 Released from the AGR Experiment Series

    Energy Technology Data Exchange (ETDEWEB)

    Scates, Dawn Marie [Idaho National Laboratory; Walter, John Bradley [Idaho National Laboratory; Reber, Edward Lawrence [Idaho National Laboratory; Sterbentz, James William [Idaho National Laboratory; Petti, David Andrew [Idaho National Laboratory

    2014-10-01

    A series of three Advanced Gas Reactor (AGR) experiments have been conducted in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). From 2006 through 2014, these experiments supported the development and qualification of the new U.S. tri structural isotropic (TRISO) particle fuel for Very High Temperature Reactors (VHTR). Each AGR experiment consisted of multiple fueled capsules, each plumbed for independent temperature control using a mix of helium and neon gases. The gas leaving a capsule was routed to individual Fission Product Monitor (FPM) detectors. For intact fuel particles, the TRISO particle coatings provide a substantial barrier to fission product release. However, particles with failed coatings, whether because of a minute percentage of initially defective particles, those which fail during irradiation, or those designed to fail (DTF) particles, can release fission products to the flowing gas stream. Because reactive fission product elements like iodine and cesium quickly deposit on cooler capsule components and piping structures as the effluent gas leaves the reactor core, only the noble fission gas isotopes of Kr and Xe tend to reach FPM detectors. The FPM system utilizes High Purity Germanium (HPGe) detectors coupled with a thallium activated sodium iodide NaI(Tl) scintillator. The germanium detector provides individual isotopic information, while the NaI(Tl) scintillator is used as a gross count rate meter. During irradiation, the 135mXe concentration reaching the FPM detectors is from both direct fission and by decay of the accumulated 135I. About ~2.5 hours after irradiation (ten 15.3 minute 135mXe half lives) the directly produced 135mXe has decayed and only the longer lived 135I remains as a source. Decay systematics dictate that 135mXe will be in secular equilibrium with its 135I parent, such that it’s production rate very nearly equals the decay rate of the parent, and its concentration in the flowing gas stream will appear to

  11. HIGH-TEMPERATURE SAFETY TESTING OF IRRADIATED AGR-1 TRISO FUEL

    Energy Technology Data Exchange (ETDEWEB)

    Stempien, John D.; Demkowicz, Paul A.; Reber, Edward L.; Chrisensen, Cad L.

    2016-11-01

    High-Temperature Safety Testing of Irradiated AGR-1 TRISO Fuel John D. Stempien, Paul A. Demkowicz, Edward L. Reber, and Cad L. Christensen Idaho National Laboratory, P.O. Box 1625 Idaho Falls, ID 83415, USA Corresponding Author: john.stempien@inl.gov, +1-208-526-8410 Two new safety tests of irradiated tristructural isotropic (TRISO) coated particle fuel have been completed in the Fuel Accident Condition Simulator (FACS) furnace at the Idaho National Laboratory (INL). In the first test, three fuel compacts from the first Advanced Gas Reactor irradiation experiment (AGR-1) were simultaneously heated in the FACS furnace. Prior to safety testing, each compact was irradiated in the Advanced Test Reactor to a burnup of approximately 15 % fissions per initial metal atom (FIMA), a fast fluence of 3×1025 n/m2 (E > 0.18 MeV), and a time-average volume-average (TAVA) irradiation temperature of about 1020 °C. In order to simulate a core-conduction cool-down event, a temperature-versus-time profile having a peak temperature of 1700 °C was programmed into the FACS furnace controllers. Gaseous fission products (i.e., Kr-85) were carried to the Fission Gas Monitoring System (FGMS) by a helium sweep gas and captured in cold traps featuring online gamma counting. By the end of the test, a total of 3.9% of an average particle’s inventory of Kr-85 was detected in the FGMS traps. Such a low Kr-85 activity indicates that no TRISO failures (failure of all three TRISO layers) occurred during the test. If released from the compacts, condensable fission products (e.g., Ag-110m, Cs-134, Cs-137, Eu-154, Eu-155, and Sr-90) were collected on condensation plates fitted to the end of the cold finger in the FACS furnace. These condensation plates were then analyzed for fission products. In the second test, five loose UCO fuel kernels, obtained from deconsolidated particles from an irradiated AGR-1 compact, were heated in the FACS furnace to a peak temperature of 1600 °C. This test had two

  12. The Anterior Gradient Homolog 3 (AGR3) Gene Is Associated with Differentiation and Survival in Ovarian Cancer

    Science.gov (United States)

    King, Erin R.; Tung, Celestine S.; Tsang, Yvonne T.M.; Zu, Zhifei; Lok, Gabriel T.M.; Deavers, Michael T.; Malpica, Anais; Wolf, Judith K.; Lu, Karen H.; Birrer, Michael J.; Mok, Samuel C.; Gershenson, David M.; Wong, Kwong-Kwok

    2011-01-01

    Low-grade serous ovarian carcinoma is believed to arise from serous borderline ovarian tumors, yet the progression from serous borderline tumors to low-grade serous ovarian carcinoma remains poorly understood. The purpose of this study was to identify differentially expressed genes between the two groups. Expression profiles were generated from 6 human ovarian surface epithelia (HOSE), 8 serous borderline ovarian tumors (SBOT), 13 low-grade serous ovarian carcinomas (LG), and 24 high-grade serous ovarian carcinomas (HG). The anterior gradient homolog 3 (AGR3) gene was found to be highly upregulated in serous borderline ovarian tumors; this finding was validated by real-time quantitative RT-PCR, Western blotting, and immunohistochemistry. Anti-AGR3 immunohistochemistry was performed on an additional 56 LG and 103 HG tissues and the results were correlated with clinical data. Expression profiling determined that 1254 genes were differentially expressed (P 10%) of AGR3 positively stained tumor cells were associated with improved longer median survival in both the LG (P = 0.013) and HG (P = 0.008) serous ovarian carcinoma groups. The progression of serous borderline ovarian tumors to low-grade serous ovarian carcinoma may involve the de-differentiation of ciliated cells. AGR3 could serve as a prognostic marker for survival in patients with low-grade and high-grade serous ovarian carcinomas. PMID:21451362

  13. The Effect of Birthrate Granularity on the Release- to- Birth Ratio for the AGR-1 In-core Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Dawn Scates; John Walter

    2012-10-01

    The AGR-1 Advanced Gas Reactor (AGR) tristructural-isotropic-particle fuel experiment underwent 13 irradiation intervals from December 2006 until November 2009 within the Idaho National Laboratory Advanced Test Reactor in support of the Next Generation Nuclear Power Plant program. During this multi-year experiment, release-to-birth rate ratios were computed at the end of each operating interval to provide information about fuel performance. Fission products released during irradiation were tracked daily by the Fission Product Monitoring System using 8-hour measurements. Birth rates calculated by MCNP with ORIGEN for as-run conditions were computed at the end of each irradiation interval. Each time step in MCNP provided neutron flux, reaction rates and AGR-1 compact composition, which were used to determine birth rates using ORIGEN. The initial birth-rate data, consisting of four values for each irradiation interval at the beginning, end, and two intermediate times, were interpolated to obtain values for each 8-hour activity. The problem with this method is that any daily changes in heat rates or perturbations, such as shim control movement or core/lobe power fluctuations, would not be reflected in the interpolated data and a true picture of the system would not be presented. At the conclusion of the AGR-1 experiment, great efforts were put forth to compute daily birthrates, which were reprocessed with the 8-hour release activity. The results of this study are presented in this paper.

  14. Human oral isolate Lactobacillus fermentum AGR1487 induces a pro-inflammatory response in germ-free rat colons

    NARCIS (Netherlands)

    Anderson, R.C.; Ulluwishewa, Dulantha; Young, Wayne; Ryan, L.J.; Henderson, Gemma; Meijerink, Marjolein; Maier, Eva; Wells, J.M.; Roy, N.C.

    2016-01-01

    Lactobacilli are thought to be beneficial for human health, with lactobacilli-associated infections being confined to immune-compromised individuals. However, Lactobacillus fermentum AGR1487 negatively affects barrier integrity in vitro so we hypothesized that it caused a pro-inflammatory

  15. Modelo de Precificação de Capital: Segmento de Commodities Agrícola

    Directory of Open Access Journals (Sweden)

    TÁCITO AUGUSTO FARIAS

    2014-12-01

    Full Text Available O objetivo do artigo é a aplicação do modelo de precificação de ativos conhecido na literatura de economia financeira como CAPITAL ASSET PRICING MODEL – MODELO DE PRECIFICAÇÃO DE ATIVOS DE CAPITAL, utilizando como ferramentas os balanços patrimoniais das empresas selecionadas. Brasil Ecodiesel indústria e comercio de biocombustíveis e óleos vegetais s.a. (v-agro e SLC Agrícola s.a. no período relativo ao ano de 2009 e 2010. Resultado fundamental: ambas as empresas no período em estudo apresentaram um beta inferior a 1, ou seja, risco menor que o risco do mercado. Descrevemos alguns resultados estatísticos que mostram o comportamento de ambas as empresas do setor de frigorifico. 

  16. AGR-1 Compact 4-1-1 Post-Irradiation Examination Results

    Energy Technology Data Exchange (ETDEWEB)

    Demkowicz, Paul Andrew [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason M. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Winston, Philip L. [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ploger, Scott A. [Idaho National Lab. (INL), Idaho Falls, ID (United States); van Rooyen, Isabella J. [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-02-01

    Destructive post-irradiation examination was performed on AGR-1 fuel Compact 4-1-1, which was irradiated to a final compact-average burnup of 19.4% FIMA (fissions per initial metal atom) and a time-average, volume-average temperature of 1072°C. The analysis of this compact focused on characterizing the extent of fission product release from the particles and examining particles to determine the condition of the kernels and coating layers. The work included deconsolidation of the compact and leach-burn-leach analysis, visual inspection and gamma counting of individual particles, metallurgical preparation of selected particles, and examination of particle cross-sections with optical microscopy, electron microscopy, and elemental analysis. Deconsolidation-leach-burn-leach (DLBL) analysis revealed no particles with failed TRISO or failed SiC layers (as indicated by very low uranium inventory in all of the leach solutions). The total fractions of the predicted compact inventories of fission products Ce-144, Cs-134, Cs-137, and Sr-90 that were present in the compact outside of the SiC layers were <2×10-6, based on DLBL data. The Ag-110m fraction in the compact outside the SiC layers was 3.3×10-2, indicating appreciable release of silver through the intact coatings and subsequent retention in the OPyC layers or matrix. The Eu-154 fraction was 2.4×10-4, which is equivalent to the inventory in one average particle, and indicates a small but measurable level of release from the intact coatings. Gamma counting of 61 individual particles indicated no particles with anomalously low fission product retention. The average ratio of measured inventory to calculated inventory was close to a value of 1.0 for several fission product isotopes (Ce-144, Cs-134, and Cs-137), indicating good retention and reasonably good agreement with the predicted inventories. Measured-to-calculated (M/C) activity ratios for fission products Eu-154, Eu-155, Ru-106, Sb

  17. Modelo organizacional da Caixa Agrícola do Litoral Centro

    OpenAIRE

    Trindade, Tiago João Pereira Cachulo da

    2009-01-01

    Relatório de Projecto / Mestrado em Gestão Este projecto estuda a implementação de um novo Modelo Organizacional para a Caixa Agrícola do Litoral Centro que deverá constituir um referencial organizacional que permita o crescimento da Instituição, que contribua para a focalização na vertente do negócio, que cumpra as exigências da Supervisão e que potencie a descentralização da tomada de decisões da Direcção para as estruturas funcionais. Como enquadramento teórico deste trab...

  18. América Latina y las exportaciones de recursos naturales agrícolas

    OpenAIRE

    Piñeiro, Martín; Bianchi, Eduardo

    2012-01-01

    La discusión sobre las estrategias de desarrollo en América Latina ha estado fuertemente influida por dos conceptos desarrollados en la literatura económica: (a) la hipótesis de que una buena dotación de recursos naturales puede tener un efecto negativo sobre el desarrollo o "la maldición de los recursos naturales'' y (b) la evidencia empírica que sugería que los términos de intercambio de la producción agrícola sufren un permanente deterioro. Una revisión de la literatura indica que la hipót...

  19. Agrícola del Instituto Tecnológico de Costa Rica

    Directory of Open Access Journals (Sweden)

    Andrei Fëdorov Fëdorov

    2007-01-01

    Full Text Available El presente artículo describe el panorama general del recién concluido proceso de rediseño curricular del plan de estudios de la licenciatura en Ingeniería Agrícola del Instituto Tecnológico de Costa Rica. A sus treinta años de existencia, este programa ha alcanzado su madurez; no obstante, ante las nuevas exigencias del desarrollo de la disciplina, del entorno productivo nacional e internacional y del contexto universitario y social, es necesario realizar su replanteamiento. El principal objetivo del proceso consiste en actualizar el programa de una manera integral y así procurar una mayor calidad formativa en esta área. Se describen los antecedentes, la metodología y los logros más destacados del rediseño.

  20. Ingeniería agrícola, una alternativa para las necesidades del agro

    OpenAIRE

    2011-01-01

    La ingeniería agrícola como profesión que articula los conceptos de la ingeniería y los procesos biológicos, está llamada a desempeñar un papel protagónico en el desarrollo del campo colombiano. Por ello requerimos espacio político para poder hacer parte de los estamentos de decisión y difundir estrategias en: - Control de erosión. - Desarrollo de tecnología apropiada a través de la investigación en las universidades colombianas. - Racionalización de las pérdidas en frutas, hortalizas y cerea...

  1. Plano de negócios Monsaluz, Sociedade Agrícola Lda.

    OpenAIRE

    Rente, José Eduardo Lopes

    2014-01-01

    Este trabalho de projeto tem como finalidade a elaboração de um plano de negócios, para reconversão de uma empresa agrícola no Alentejo, com um investimento na produção de ovinos de aptidão leiteira. O presente trabalho de projeto é apresentado metodologicamente através de um plano de negócio, que se pretende constitua um guia de apoio á tomada de decisão na implantação e controlo desse projeto. Com base na caracterização e análise da situação atual da empresa, na análise do...

  2. Modelo organizacional da Caixa Agrícola do Litoral Centro

    OpenAIRE

    Trindade, Tiago João Pereira Cachulo da

    2009-01-01

    Relatório de Projecto / Mestrado em Gestão Este projecto estuda a implementação de um novo Modelo Organizacional para a Caixa Agrícola do Litoral Centro que deverá constituir um referencial organizacional que permita o crescimento da Instituição, que contribua para a focalização na vertente do negócio, que cumpra as exigências da Supervisão e que potencie a descentralização da tomada de decisões da Direcção para as estruturas funcionais. Como enquadramento teórico deste trab...

  3. Ingeniería agrícola, una alternativa para las necesidades del agro

    Directory of Open Access Journals (Sweden)

    Julio E. Ospina M.

    2011-02-01

    Full Text Available La ingeniería agrícola como profesión que articula los conceptos de la ingeniería y los procesos biológicos, está llamada a desempeñar un papel protagónico en el desarrollo del campo colombiano. Por ello requerimos espacio político para poder hacer parte de los estamentos de decisión y difundir estrategias en: - Control de erosión. - Desarrollo de tecnología apropiada a través de la investigación en las universidades colombianas. - Racionalización de las pérdidas en frutas, hortalizas y cereales, entre otros".

  4. Importance of the global regulators Agr and SaeRS in the pathogenesis of CA-MRSA USA300 infection.

    Directory of Open Access Journals (Sweden)

    Christopher P Montgomery

    Full Text Available CA-MRSA infection, driven by the emergence of the USA300 genetic background, has become epidemic in the United States. USA300 isolates are hypervirulent, compared with other CA- and HA-MRSA strains, in experimental models of necrotizing pneumonia and skin infection. Interestingly, USA300 isolates also have increased expression of core genomic global regulatory and virulence factor genes, including agr and saeRS. To test the hypothesis that agr and saeRS promote the observed hypervirulent phenotype of USA300, isogenic deletion mutants of each were constructed in USA300. The effects of gene deletion on expression and protein abundance of selected downstream virulence genes were assessed by semiquantitative real-time reverse-transcriptase PCR (qRT-PCR and western blot, respectively. The effects of gene deletion were also assessed in mouse models of necrotizing pneumonia and skin infection. Deletion of saeRS, and, to a lesser extent, agr, resulted in attenuated expression of the genes encoding α-hemolysin (hla and the Panton-Valentine leukocidin (lukSF-PV. Despite the differences in hla transcription, the toxin was undetectable in culture supernatants of either of the deletion mutants. Deletion of agr, but not saeRS, markedly increased the expression of the gene encoding protein A (spa, which correlated with increased protein abundance. Each deletion mutant demonstrated significant attenuation of virulence, compared with wild-type USA300, in mouse models of necrotizing pneumonia and skin infection. We conclude that agr and saeRS each independently contribute to the remarkable virulence of USA300, likely by means of their effects on expression of secreted toxins.

  5. Data Compilation for AGR-3/4 Designed-to-Fail (DTF) Fuel Particle Batch LEU04-02DTF

    Energy Technology Data Exchange (ETDEWEB)

    Hunn, John D [ORNL; Miller, James Henry [ORNL

    2008-10-01

    This document is a compilation of coating and characterization data for the AGR-3/4 designed-to-fail (DTF) particles. The DTF coating is a high density, high anisotropy pyrocarbon coating of nominal 20 {micro}m thickness that is deposited directly on the kernel. The purpose of this coating is to fail early in the irradiation, resulting in a controlled release of fission products which can be analyzed to provide data on fission product transport. A small number of DTF particles will be included with standard TRISO driver fuel particles in the AGR-3 and AGR-4 compacts. The ORNL Coated Particle Fuel Development Laboratory 50-mm diameter fluidized bed coater was used to coat the DTF particles. The coatings were produced using procedures and process parameters that were developed in an earlier phase of the project as documented in 'Summary Report on the Development of Procedures for the Fabrication of AGR-3/4 Design-to-Fail Particles', ORNL/TM-2008/161. Two coating runs were conducted using the approved coating parameters. NUCO425-06DTF was a final process qualification batch using natural enrichment uranium carbide/uranium oxide (UCO) kernels. After the qualification run, LEU04-02DTF was produced using low enriched UCO kernels. Both runs were inspected and determined to meet the specifications for DTF particles in section 5 of the AGR-3 & 4 Fuel Product Specification (EDF-6638, Rev.1). Table 1 provides a summary of key properties of the DTF layer. For comparison purposes, an archive sample of DTF particles produced by General Atomics was characterized using identical methods. This data is also summarized in Table 1.

  6. La normalización y certificación de tractores agrícolas en México

    Directory of Open Access Journals (Sweden)

    Alma Velia Ayala Garay

    2013-01-01

    Full Text Available El tractor agrícola es la principal fuente de potencia dentro de una unidad de producción. Por lo tanto para los usuarios de maquinaria agrícola, resulta una prioridad contar con mecanismos que permitan dar seguridad al usuario final o productor agrícola en el funcionamiento y calidad de los tractores, para esto el objetivo del presente es dar a conocer la evolución de la normalización y certificación de la maquinaria agrícola en México, sus impactos y tendencias, por medio de una descripción de conceptos y organismos internacionales que han sido referencia para México, así como la descripción de las actividades del CENEMA y OCIMA. Para esto se tomaron definiciones y datos estadísticos de cantidad de modelos de tractores certificados, cantidad de certificados otorgados sobre estructuras de protección por OCIMA, cantidad de motocultores e implementos certificados, dictaminaciones de tractores no favorables, de múltiples sectores. Como resultado de la certificación de la ma- quinaria agrícola se obtuvo hasta junio de 2013, existen 76 tractores certificados con una potencia a la “toma de fuerza” que varía de los 18,3 a los 130 hp. Por ultimo cabe destacar que la finalidad de OCIMA es respaldar al agricultor y avalar que se cumple con las normas mexicanas (NMX y las especificaciones necesarias para garantizar el buen desempeño de su equipo.

  7. AGR-2 Final Data Qualification Report for U.S. Capsules - ATR Cycles 147A Through 154B

    Energy Technology Data Exchange (ETDEWEB)

    Pham, Binh T. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Very High-Temperature Reactor Technology Development Office; Einerson, Jeffrey J. [Idaho National Lab. (INL), Idaho Falls, ID (United States). Very High-Temperature Reactor Technology Development Office

    2014-07-01

    This report provides the data qualification status of AGR-2 fuel irradiation experimental data in four U.S. capsules from all 15 Advanced Test Reactor (ATR) Cycles 147A, 148A, 148B, 149A, 149B, 150A, 150B, 151A, 151B, 152A, 152B, 153A, 153B, 154A, and 154B, as recorded in the Nuclear Data Management and Analysis System (NDMAS). Thus, this report covers data qualification status for the entire AGR-2 irradiation and will replace four previously issued AGR-2 data qualification reports (e.g., INL/EXT-11-22798, INL/EXT-12-26184, INL/EXT-13-29701, and INL/EXT-13-30750). During AGR-2 irradiation, two cycles, 152A and 153A, occurred when the ATR core was briefly at low power, so AGR-2 irradiation data are not used for physics and thermal calculations. Also, two cycles, 150A and 153B, are Power Axial Locator Mechanism (PALM) cycles when the ATR power is higher than during normal cycles. During the first PALM cycle, 150A, the experiment was temporarily moved from the B-12 location to the ATR water canal and during the second PALM cycle, 153B, the experiment was temporarily moved from the B-12 location to the I-24 location to avoid being overheated. During the “Outage” cycle, 153A, seven flow meters were installed downstream from seven Fission Product Monitoring System (FPMS) monitors to measure flows from the monitors and these data are included in the NDMAS database.

  8. Productividad del agua en algunos cultivos agrícolas en Cuba

    Directory of Open Access Journals (Sweden)

    Felicita González Robaina

    2014-01-01

    Full Text Available Para el mejor uso económico y social del agua se requieren de métodos para evaluar su productividad, a fin de tomar mejores decisiones en cuanto a políticas y estrategias de utilización de manera sostenible. Los administradores del agua para el riego necesitan iden- tificar tendencias en los patrones de uso y niveles de eficiencia con vistas a fijar metas y mejorar la productividad por unidad de volumen utilizado y/o consumido. El objetivo de este trabajo fue presentar los indicadores de productividad agronómica del agua de 17 cultivos a partir de la información obtenida en más de 100 experimentos de campo disponibles en la base de datos sobre necesidades hídricas del Instituto de Investigaciones de Ingeniería Agrícola. Se determinaron los rendimientos máximo y mínimo y sus respectivos valores de consumo, agua aplicada por riego y la productividad agronómica del agua aplicada para los 17 cultivos estudiados. Cultivos como los frijoles, maíz, boniato y los plátanos obtienen incrementos de rendimiento superiores al 100% cuando se aplica el agua necesaria para satisfacer su demanda hídrica, mientras que la yuca obtuvo valores menores del 50%. Los altos valores obtenidos de productividad en base al agua utilizada como riego no son un buen indicador del uso eficiente del agua por las plantas para las condiciones de la zona de estudio, donde se informan para los años analizados, porcentajes de lluvia aprovechable de hasta el 41%, supliendo ésta una parte importante de las necesidades de los cultivos agrícolas.

  9. Combining models of behaviour with operational data to provide enhanced condition monitoring of AGR cores

    Energy Technology Data Exchange (ETDEWEB)

    West, Graeme M., E-mail: graeme.west@strath.ac.uk; Wallace, Christopher J.; McArthur, Stephen D.J.

    2014-06-01

    Highlights: • Combining laboratory model outputs with operational data. • Isolation of single component from noisy data. • Better understanding of the health of graphite cores. • Extended plant operation through leveraging existing data sources. - Abstract: Installation of new monitoring equipment in Nuclear Power Plants (NPPs) is often difficult and expensive and therefore maximizing the information that can be extracted from existing monitoring equipment is highly desirable. This paper describes the process of combining models derived from laboratory experimentation with current operational plant data to infer an underlying measure of health. A demonstration of this process is provided where the fuel channel bore profile, a measure of core health, is inferred from data gathered during the refuelling process of an Advanced Gas-cooled Reactor (AGR) nuclear power plant core. Laboratory simulation was used to generate a model of an interaction between the fuel assembly and the core. This model is used to isolate a single frictional component from a noisy input signal and use this friction component as a measure of health to assess the current condition of the graphite bricks that comprise the core. In addition, the model is used to generate an expected refuelling response (the noisy input signal) for a given set of channel bore diameter measurements for either insertion of new fuel or removal of spent fuel, providing validation of the model. This benefit of this work is that it provides a greater understanding of the health of the graphite core, which is important for continued and extended operation of the AGR plants in the UK.

  10. An Assessment of ORNL PIE Capabilities for the AGR Program Capsule Post Irradiation Examination

    Energy Technology Data Exchange (ETDEWEB)

    Morris, Robert Noel [ORNL

    2006-09-01

    ORNL has facilities and experienced staff that can execute +the Advanced Gas Reactor (AGR) Post Irradiation Examination (PIE) task. While the specific PIE breakdown needs to be more formally defined, the basic outline is clear and the existing capabilities can be assessed within the needs of the tasks defined in the program plan. A one-to-one correspondence between the program plan tasks and the current ORNL PIE status was conducted and while some shortcomings were identified, the general capability is available. Specific upgrade needs were identified and reviewed. A path forward was formulated. Building 3525 is available for this work and this building is currently receiving renewed attention from management so that it will be in good working order prior to the expected PIE start date. This building is equipped with the tools necessary for PIEs of this nature, but the long hiatus in coated particle fuel work has left it with aging analysis tools. This report identified several of these tools and rough estimates of what would be required to update and replace them. In addition, other ORNL buildings are available to support Building 3525 in specialized tasks along with the normal laboratory infrastructure. Before the AGR management embarks on any equipment development effort, the PIE tasks should be updated against current program (modeling and data) needs and better defined so that the items to be measured, their measurement uncertainties, and thru-put needs can be reviewed. A Data Task Matrix (DTM) should be prepared so that the program data needs can be compared against the identified PIE tasks and what is practical in the hot cell environment to make sure nothing is overlooked. Finally, thought should be given to the development of standardized equipment designs between sites to avoid redundant design efforts and different measurement techniques. This is a potentially cost saving effort that can also avoid data inconsistencies.

  11. A New Type of Deaggregators, the Bolaamphiphilic DeAgrs.Observations of the Dependence of Deaggregating Ability on Aggregator Concentration and Solvent Aggregating Power

    Institute of Scientific and Technical Information of China (English)

    ZHOU,Qi-Zhong(周其忠); SHI,Ji-Liang(史济良); JIANG,Xi-Kui(蒋锡夔); LI,Zhan-Ting(黎占亭)

    2002-01-01

    Four new amphiphilic molecules, i. e., the bolaamphipiles ω-trimethylamino n-hexadecanoate( deAgr 16 ), n-dodecanoate (deAgr 12), n-undecanoate(deAgr 11), and n-octanoate (deAgr 8)were synthesized. Their ability as deaggregators to break up the aggregating systems of hexadecyl β-naphthoate (A16) and dodecyl β-naphthoate (A12) in dioxanewater binary solvent systems was investigated in a mumber of solvent systems and at different A16 and A12 concentrations.The results reveal that this new type of bolaamphiphilic molecules appears to be one of the most efficient deaggregators reported, which, at very low concentrations, can effectively break up the aggregating systems of highly concentrated A16and A12. It is also found that bolaamphiphiles with longer aliphatic chains possess greater deaggregatibg ability. However, when the overall overall concentrations of A16 and A12 are very low but still above their critiical aggregating concentration,thee bolaamphiphilic molecules lose their deaggregating power and tend to coaggregate with the aggregated A16 or A12molecules. The quite efficient deaggregating ability of the longchain bolaamphiphiles (deAgr 16 and deAgr 12), as compared to the short-chain deAgr 8, has been ascribed to their dynamic switch-on/switch-off behavior involving coiled-up and uncoiled conformations of their long aliphatic chains.

  12. Structural Characterization of Native Autoinducing Peptides and Abiotic Analogs Reveals Key Features Essential for Activation and Inhibition of an AgrC Quorum Sensing Receptor in Staphylococcus aureus

    OpenAIRE

    Tal-Gan, Yftah; Ivancic, Monika; Cornilescu, Gabriel; Cornilescu, Claudia C.; Blackwell, Helen E.

    2013-01-01

    Staphylococcus aureus is a major human pathogen that uses quorum sensing (QS) to control virulence. Its QS system is regulated by macrocyclic peptide signals (or autoinducing peptides (AIPs)) and their cognate transmembrane receptors (AgrCs). Four different specificity groups of S. aureus have been identified to date (groups I–IV), each of which uses a different AIP:AgrC pair. Non-native ligands capable of intercepting AIP:AgrC binding, and thereby QS, in S. aureus have attracted considerable...

  13. Necesidades educacionales sobre riesgo de plaguicidas en el contexto socio-ambiental de las comunidades agrícolas de Sonora

    OpenAIRE

    M.I. Silveira Gramont; L. Aldana Madrid; A.I. Valenzuela Quintanar; C.B. Ochoa Nogales; G. Jasa-Silveira; Beatriz Camarena Gómez

    2016-01-01

    Para proponer estrategias de educación y comunicación sobre plaguicidas en las comunidades agrícolas de Sonora, se requiere situar la problemática de la exposición a plaguicidas en el contexto socio-cultural y ambiental de las comunidades afectadas, tomando en cuenta los factores que contribuyen al mayor riesgo de exposición de los trabajadores agrícolas y de sus familias. Este estudio examina los factores poblacionales, educacionales, culturales y de trabajo de habitantes y trabajadores agrí...

  14. Metodología para evaluar el impacto de la maquinaria agrícola sobre los recursos naturales del medio ambiente

    Directory of Open Access Journals (Sweden)

    Norge Díaz Rodríguez

    2007-01-01

    Full Text Available Se realizó una propuesta de metodología para evaluar el impacto que ejerce la maquinaria agrícola sobre algunos de los recursos naturales del medio ambiente. Durante su explotación la maquinaria agrícola, como unidad energética para el trabajo agrícola, produce un conjunto de impactos negativos sobre el medio en tres direcciones fundamentales: suelo, aire, y agua. A pesar de existir conciencia sobre este problema, no se disponen de herramientas apropiadas para hacer una evaluación certera de la magnitud de estos impactos, lo cual no es una simple tarea.

  15. A competitividade do regadio em Portugal no contexto da Nova Política Agrícola Comum: o caso de uma exploração agrícola no Alentejo

    Directory of Open Access Journals (Sweden)

    Rui Manuel Sousa Fragoso

    2007-03-01

    Full Text Available A Nova Reforma da Política Agrícola Comum (PAC aprovada em 2003 constitui um reforço dos principais objectivos das reformas anteriores de 1992 e de 2000, como a promoção da competitividade do sector agrícola, da multifuncionalidade dos espaços rurais e agrícolas e da exploração sustentável dos recursos. No essencial, substituem-se as ajudas diretas à produção previstas na maioria dos regulamentos das Organizações Comuns de Mercado, por um regime de pagamento único por exploração sujeito a normas de eco-condicionalidade e a limitações na reconversão dos sistemas de produção agrícola. Este artigo avalia os impactos da nova PAC na competitividade do regadio em Portugal nas explorações agrícolas do Alentejo, nomeadamente, dos efeitos do pagamento único na afetação e na retribuição dos recursos agrícolas, de modo a identificar as principais alterações nas orientações produtivas e nos rendimentos agrícolas. Também são avaliados alguns dos principais impactos sócio-econômicos e ambientais diretos decorrentes dos ajustamentos produzidos com a Nova PAC. A metodologia utilizada baseia-se no desenvolvimento de um modelo micro-econômico de programação matemática estocástica discreta de maximização do valor esperado e de minimização do risco, adaptado às características de uma empresa agrícola do Alentejo. O modelo é utilizado para avaliar prospectivamente o plano de produção e o rendimento no curto e no longo prazo, mediante os cenários da reforma da PAC de 2000 e da Nova Reforma da PAC de 2003.The 2003 Common Agricultural Policy (CAP reform constitutes a reinforcement of the main objectives of the previous reforms of 1992 and of 2000, namely the promotion of the agricultural competitiveness, the multiple functions of the rural and agricultural areas and the sustainable resource exploitation. The direct production aids in the most Common Market Organizations are replaced by an only payment for each

  16. Aspectos constitucionais do direito agrário emenda constitucional N° 10/64

    Directory of Open Access Journals (Sweden)

    José Carlos Vieira

    1988-07-01

    Full Text Available This paper, presents a brief history of the constitutional work applied to property rights in Brazil, mainly to those regarding land property. lt also shows the development of agrarian rights as an independent branch of the juridical prescription up to its effective recognition. It slightly shows the important role of the social function of property in constitutional texts as to support governmental actions aiming at an agrarian reform, and any other tendency to alter the rural profile of the country. This work is aimed to show that, despite a set of laws related to the agrarian reality of this country, the facts and data make it clear that nothing has been done about it up to today. The research Our constitutional texts shows that some advances towards the effectiveness of the social function of property principles have been made; nevertheless, the constitution to be promulgated by the year 1988, surprisingly takes a step backwards as to this chapter for it decreases the scope that it had in former constitutions and even in the original ones by authoritarian governments.O presente trabalho contém um resumo histórico do tratamento constitucional reservado ao direito de propriedade no Brasil, especialmente à propriedade da terra, bem assim a evolução do direito agrário como ramo autônomo do ordenamento jurídico, até o seu efetivo reconhecimento como tal. Registra, mesmo que rapidamente, a importância que teve a adotação do princípio da "função social da propriedade" nos textos constitucionais, de forma a respaldar ações governamentais objetivando a realização da reforma agrária e outras medidas tendentes a alterar o perfil rural do país. O trabalho procura mostrar, também, que, malgrado dispor o pais de um rol de leis capazes de dar suporte a propostas destinadas a promover uma efetiva mudança na realidade agrária, os fatos demonstram claramente que isto não ocorreu até hoje. A pesquisa nos textos constitucionais mostra

  17. AGR-3/4 Irradiation Test Train Disassembly and Component Metrology First Look Report

    Energy Technology Data Exchange (ETDEWEB)

    Stempien, John Dennis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rice, Francine Joyce [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Winston, Philip Lon [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-03-01

    The AGR-3/4 experiment was designed to study fission product transport within graphitic matrix material and nuclear-grade graphite. To this end, this experiment consisted of 12 capsules, each fueled with 4 compacts containing UCO TRISO particles as driver fuel and 20 UCO designed-to-fail (DTF) fuel particles in each compact. The DTF fuel was fabricated with a thin pyrocarbon layer which was intended to fail during irradiation and provide a source of fission products. These fission products could then migrate through the compact and into the surrounding concentric rings of graphitic matrix material and/or nuclear graphite. Through post-irradiation examination (PIE) of the rings (including physical sampling and gamma scanning) fission product concentration profiles within the rings can be determined. These data can be used to elucidate fission product transport parameters (e.g. diffusion coefficients within the test materials) which will be used to inform and refine models of fission product transport. After irradiation in the Advanced Test Reactor (ATR) had been completed in April 2014, the AGR-3/4 experiment was shipped to the Hot Fuel Examination Facility (HFEF) at the Materials and Fuels Complex (MFC) for inspection, disassembly, and metrology. The AGR-3/4 test train was received at MFC in two separate shipments between February and April 2015. Visual examinations of the test train exterior did not indicate dimensional distortion, and only two small discolored areas were observed at the bottom of Capsules 8 and 9. No corresponding discoloration was found on the inside of these capsules, however. Prior to disassembly, the two test train sections were subject to analysis via the Precision Gamma Scanner (PGS), which did not indicate that any gross fuel relocation had occurred. A series of specialized tools (including clamps, cutters, and drills) had been designed and fabricated in order to carry out test train disassembly and recovery of capsule components (graphite

  18. AGR-3/4 Irradiation Test Train Disassembly and Component Metrology First Look Report

    Energy Technology Data Exchange (ETDEWEB)

    Stempien, John Dennis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rice, Francine Joyce [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Winston, Philip Lon [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    The AGR-3/4 experiment was designed to study fission product transport within graphitic matrix material and nuclear-grade graphite. To this end, this experiment consisted of 12 capsules, each fueled with 4 compacts containing UCO TRISO particles as driver fuel and 20 UCO designed-to-fail (DTF) fuel particles in each compact. The DTF fuel was fabricated with a thin pyrocarbon layer which was intended to fail during irradiation and provide a source of fission products. These fission products could then migrate through the compact and into the surrounding concentric rings of graphitic matrix material and/or nuclear graphite. Through post-irradiation examination (PIE) of the rings (including physical sampling and gamma scanning) fission product concentration profiles within the rings can be determined. These data can be used to elucidate fission product transport parameters (e.g. diffusion coefficients within the test materials) which will be used to inform and refine models of fission product transport. After irradiation in the Advanced Test Reactor (ATR) had been completed in April 2014, the AGR-3/4 experiment was shipped to the Hot Fuel Examination Facility (HFEF) at the Materials and Fuels Complex (MFC) for inspection, disassembly, and metrology. The AGR-3/4 test train was received at MFC in two separate shipments between February and April 2015. Visual examinations of the test train exterior did not indicate dimensional distortion, and only two small discolored areas were observed at the bottom of Capsules 8 and 9. No corresponding discoloration was found on the inside of these capsules, however. Prior to disassembly, the two test train sections were subject to analysis via the Precision Gamma Scanner (PGS), which did not indicate that any gross fuel relocation had occurred. A series of specialized tools (including clamps, cutters, and drills) had been designed and fabricated in order to carry out test train disassembly and recovery of capsule components (graphite

  19. Reforma agrária: o impossível diálogo sobre a História possível

    OpenAIRE

    José de Souza Martins

    1999-01-01

    Os desencontros entre o governo, de um lado, e o MST, a Igreja e as oposições, de outro, quanto à política de reforma agrária, só podem ser compreendidos se tivermos em conta o que vem a ser a questão agrária no Brasil. Num país em que o grande capital se tornou proprietário de terras, a concepção clássica da questão agrária, e das reformas que ela pede, fica substancialmente alterada. São essas alterações que propõem as condições e os limites da reforma agrária no país. São elas, também que ...

  20. Emisiones de gases de efecto invernadero en sistemas agrícolas de México

    Directory of Open Access Journals (Sweden)

    Vinisa Saynes Santillán

    2016-03-01

    Full Text Available La agricultura es el sustento para la alimentación de una población mundial creciente. La agricultura es la cuarta causa de emisiones de GEI, y emite grandes cantidades de los llamados “gases que no son CO2” incluyendo al N2O y el CH4 con un poder de calentamiento 265 y 28 veces, respectivamente, mayor en comparación con el CO2. En México la información de las emisiones de GEI se reporta en diversos foros y desde diferentes perspectivas. En este trabajo se recopiló información de las emisiones de GEI de las Comunicaciones Nacionales y el Primer Informe Bienal, de publicaciones arbitradas por pares y de la literatura gris. Las emisiones del sector agrícola reportadas en las diferentes Comunicaciones presentan inconsistencias debido a factores como falta de información y de acceso a esta en las primeras dos Comunicaciones y a cuestiones de tipo metodológico en las Comunicaciones subsecuentes. De acuerdo con las estimaciones más actuales (Informe Bienal, las actividades agropecuarias son la tercera causa de generación de emisiones de GEI con una contribución del 12% a las emisiones nacionales. Dentro de esta categoría la mayor parte de las emisiones se generan por la fermentación entérica, el manejo del estiércol y por el uso de fertilizantes en los suelos agrícolas. Los principales retos para mejorar las estimaciones y reducir su incertidumbre es la generación de factores de emisión nacionales para lo cual es esencial contar con mayor información de las fuentes clave. En este trabajo se encontró que existe información relevante que sería de utilidad pero se encuentra dispersa por lo que falta síntesis y organización de la información sobre todo de la que se encuentra en la literatura gris.

  1. AGR-1 Fuel Compact 6-3-2 Post-Irradiation Examination Results

    Energy Technology Data Exchange (ETDEWEB)

    Paul demkowicz; jason Harp; Scott Ploger

    2012-12-01

    Destructive post-irradiation examination was performed on fuel Compact 6-3-2, which was irradiated in the AGR-1 experiment to a final compact average burnup of 11.3% FIMA and a time-average, volume-average temperature of 1070°C. The analysis of this compact was focused on characterizing the extent of fission product release from the particles and examining particles to determine the condition of the kernels and coating layers. The work included deconsolidation of the compact and leach-burn-leach analysis, visual inspection and gamma counting of individual particles, measurement of fuel burnup by several methods, metallurgical preparation of selected particles, and examination of particle cross-sections with optical microscopy. A single particle with a defective SiC layer was identified during deconsolidation-leach-burn-leach analysis, which is in agreement with previous measurements showing elevated cesium in the Capsule 6 graphite fuel holder associated with this fuel compact. The fraction of the compact europium inventory released from the particles and retained in the matrix was relatively high (approximately 6E-3), indicating release from intact particle coatings. The Ag-110m inventory in individual particles exhibited a very broad distribution, with some particles retaining =80% of the predicted inventory and others retaining less than 25%. The average degree of Ag-110m retention in 60 gamma counted particles was approximately 50%. This elevated silver release is in agreement with analysis of silver on the Capsule 6 components, which indicated an average release of 38% of the Capsule 6 inventory from the fuel compacts. In spite of the relatively high degree of silver release from the particles, virtually none of the Ag-110m released was found in the compact matrix, and presumably migrated out of the compact and was deposited on the irradiation capsule components. Release of all other fission products from the particles appears to be less than a single

  2. KEY RESULTS FROM IRRADIATION AND POST-IRRADIATION EXAMINATION OF AGR-1 UCO TRISO FUEL

    Energy Technology Data Exchange (ETDEWEB)

    Demkowicz, Paul A.; Hunn, John D.; Petti, David A.; Morris, Robert N.

    2016-11-01

    The AGR-1 irradiation experiment was performed as the first test of tristructural isotropic (TRISO) fuel in the US Advanced Gas Reactor Fuel Development and Qualification Program. The experiment consisted of 72 right cylinder fuel compacts containing approximately 3×105 coated fuel particles with uranium oxide/uranium carbide (UCO) fuel kernels. The fuel was irradiated in the Advanced Test Reactor for a total of 620 effective full power days. Fuel burnup ranged from 11.3 to 19.6% fissions per initial metal atom and time average, volume average irradiation temperatures of the individual compacts ranged from 955 to 1136°C. This paper focuses on key results from the irradiation and post-irradiation examination, which revealed a robust fuel with excellent performance characteristics under the conditions tested and have significantly improved the understanding of UCO coated particle fuel irradiation behavior within the US program. The fuel exhibited a very low incidence of TRISO coating failure during irradiation and post-irradiation safety testing at temperatures up to 1800°C. Advanced PIE methods have allowed particles with SiC coating failure to be isolated and meticulously examined, which has elucidated the specific causes of SiC failure in these specimens. The level of fission product release from the fuel during irradiation and post-irradiation safety testing has been studied in detail. Results indicated very low release of krypton and cesium through intact SiC and modest release of europium and strontium, while also confirming the potential for significant silver release through the coatings depending on irradiation conditions. Focused study of fission products within the coating layers of irradiated particles down to nanometer length scales has provided new insights into fission product transport through the coating layers and the role various fission products may have on coating integrity. The broader implications of these results and the application of

  3. Materials and boiler rig testing to support chemical cleaning of once-through AGR boilers

    Energy Technology Data Exchange (ETDEWEB)

    Tice, D.R.; Platts, N.; Raffel, A.S. [Serco Assurance (United Kingdom); Rudge, A. [British Energy Generation Ltd. (United Kingdom)

    2002-07-01

    An extensive programme of work has been carried out to evaluate two candidate inhibited cleaning solutions for possible implementation on plant, which would be the first chemical clean of an AGR boiler. The two candidate cleaning solutions considered were a Stannine-inhibited citric acid/formic acid mixture (GOM106) and inhibited hydrofluoric acid. Citric acid-based cleaning processes are widely used within the UK Power Industry. The GOM106 solution, comprising a mixture of 3% citric acid, 0.5% formic acid and 0.05% Stannine LTP inhibitor, buffered with ammonia to pH 3.5, was developed specifically for the AGR boilers during the 1970's. Although a considerable amount of materials testing work was carried out by British Energy's predecessor companies to produce a recommended cleaning procedure there were some remaining concerns with the use of GOM106, from these earlier studies, for example, an increased risk of pitting attack associated with the removal of thick 9Cr oxide deposits and a risk of unacceptable damage in critical locations such as the upper transition joints and other weld locations. Hence, additional testing was still required to validate the solution for use on plant. Inhibited hydrofluoric acid (HFA) was also evaluated as an alternative reagent to GOM106. HFA has been used extensively for cleaning mild and low'alloy steel boiler tubes in fossil-fired plant in the UK and elsewhere in Europe and is known to remove oxide quickly. Waste treatment is also easier than for the GOM106 process and some protection against damage to the boiler tube materials is provided by complexing of fluoride with ferric ion. Validation of the potential reagents and inhibitors was achieved by assessing the rate and effectiveness of oxide removal from specimens of helical boiler tubing and welds, together with establishing the extent of any metal loss or localised damage. The initial materials testing resulted in the inhibited ammoniated citric / formic acid

  4. Convergencia espacial y concentración regional agrícola en México 1970-2003

    OpenAIRE

    Normand Eduardo Asuad Sanén; Luis Quintana Romero; Roberto Ramírez Hernández

    2007-01-01

    El propósito de este trabajo es analizar la relación entre convergencia tradicional y espacial del ingreso según la concentración regional de la producción agrícola de México, destacando los efectos propiciados por el cambio del modelo de desarrollo y gestión, mediante la liberalización y privatización de la economía con su incorporación al TLCAN y su comparación con el periodo 1970-2004. Se identifican y delimitan las regiones agrícolas a las que se aplica la medición econométrica de las hip...

  5. Convergencia espacial y concentración regional agrícola en México 1970-2003

    OpenAIRE

    Normand Eduardo Asuad Sanén; Luis Quintana Romero; Roberto Ramírez Hernández

    2007-01-01

    El propósito de este trabajo es analizar la relación entre convergencia tradicional y espacial del ingreso según la concentración regional de la producción agrícola de México, destacando los efectos propiciados por el cambio del modelo de desarrollo y gestión, mediante la liberalización y privatización de la economía con su incorporación al TLCAN y su comparación con el periodo 1970-2004. Se identifican y delimitan las regiones agrícolas a las que se aplica la medición econométrica de las hip...

  6. La prensa agrícola del porfiriato como Fuente para la historia económica. (Ensayo de Fuentes

    Directory of Open Access Journals (Sweden)

    Ma. Cecilia Zuleta

    1999-01-01

    Full Text Available Al llegar al poder el presidente de MCxico Porfirio DSaz, la &te política del país consideró que el principal problema de MCxico era el atraso económico, por lo que era indispensable impulsar.el "desarrollo económico", cuya actividad primordial, era la agricultura comercial. Por tanto, comenzó a producirse entre los sectores intelectuales, políticos y de negocios una revalorización de la importancia de la actividad agrícola y con ello, el surgimiento de publicaciones especializadas en asuntos agrícolas que son, en la actualidad, una fuente importante para reconstruir la historia econ6- mica del periodo.

  7. Prospectiva tecnológica y consideraciones curriculares en Ingeniería Agrícola

    Directory of Open Access Journals (Sweden)

    Jaime Salazar Contreras

    2011-01-01

    Full Text Available Los nuevos modelos económicos centrados en un mayor número de productos de exportación con un alto valor agregado hace necesario que se generen grandes desarrollos tecnológicos, en los cuales el papel de la Ingeniería es trascendental; para el caso de Ingeniería Agrícola se debe lograr importantes tecnificaciones del Sector Agropecuario para poder atender las demandas de productos alimenticios, para consumo interno y excedentes para otros países. Con el presente escrito se mostrará una visión prospectiva a nivel nacional e internacional de la Ingeniería Agrícola y fmalrnente algunas consideraciones sobre su currículo, con el propósito de reflexionar, cómo sería una formación competitiva, en los albores del siglo XXI.

  8. Electron Microscopic Examination of Irradiated TRISO Coated Particles of Compact 6-3-2 of AGR-1 Experiment

    Energy Technology Data Exchange (ETDEWEB)

    Van Rooyen, Isabella Johanna [Idaho National Lab. (INL), Idaho Falls, ID (United States); Demkowicz, Paul Andrew [Idaho National Lab. (INL), Idaho Falls, ID (United States); Riesterer, Jessica Lori [Idaho National Lab. (INL), Idaho Falls, ID (United States); Miller, Brandon Douglas [Idaho National Lab. (INL), Idaho Falls, ID (United States); Janney, Dawn Elizabeth [Idaho National Lab. (INL), Idaho Falls, ID (United States); Harp, Jason Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Ploger, Scott Arden [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2012-12-01

    The electron microscopic examination of selected irradiated TRISO coated particles of the AGR-1 experiment of fuel compact 6-3-2 are presented in this report. Compact 6-3-2 refers to the compact in Capsule 6 at level 3 of Stack 2. The fuel used in capsule 6 compacts, are called the “baseline” fuel as it is fabricated with refined coating process conditions used to fabricate historic German fuel, because of its excellent irradiation performance with UO2 kernels. The AGR-1 fuel is however made of low-enriched uranium oxycarbide (UCO). Kernel diameters are approximately 350 µm with a U-235 enrichment of approximately 19.7%. Compact 6-3-2 has been irradiated to 11.3% FIMA compact average burn-up with a time average, volume average temperature of 1070.2°C and with a compact average fast fluence of 2.38E21 n/cm

  9. Ensino agrícola e influência norte-americana no Brasil (1945-1961

    Directory of Open Access Journals (Sweden)

    Sonia Regina de Mendonça

    2010-12-01

    Full Text Available O artigo trata das redefinições sofridas pelo Ensino Agrícola no Brasil, a partir da conjuntura marcada pelo fim da II Guerra Mundial/Guerra Fria, quando inúmeros acordos de "cooperação técnica" seriam firmados entre os governos brasileiro e estadunidense, objetivando "recuperar" seu novo público-alvo: o trabalhador rural adulto e analfabeto.

  10. Mobile genetic element SCCmec-encoded psm-mec RNA suppresses translation of agrA and attenuates MRSA virulence.

    Science.gov (United States)

    Kaito, Chikara; Saito, Yuki; Ikuo, Mariko; Omae, Yosuke; Mao, Han; Nagano, Gentaro; Fujiyuki, Tomoko; Numata, Shunsuke; Han, Xiao; Obata, Kazuaki; Hasegawa, Setsuo; Yamaguchi, Hiroki; Inokuchi, Koiti; Ito, Teruyo; Hiramatsu, Keiichi; Sekimizu, Kazuhisa

    2013-01-01

    Community acquired-methicillin resistant Staphylococcus aureus (CA-MRSA) is a socially problematic pathogen that infects healthy individuals, causing severe disease. CA-MRSA is more virulent than hospital associated-MRSA (HA-MRSA). The underlying mechanism for the high virulence of CA-MRSA is not known. The transcription product of the psm-mec gene, located in the mobile genetic element SCCmec of HA-MRSA, but not CA-MRSA, suppresses the expression of phenol-soluble modulin α (PSMα), a cytolytic toxin of S. aureus. Here we report that psm-mec RNA inhibits translation of the agrA gene encoding a positive transcription factor for the PSMα gene via specific binding to agrA mRNA. Furthermore, 25% of 325 clinical MRSA isolates had a mutation in the psm-mec promoter that attenuated transcription, and 9% of the strains had no psm-mec. In most of these psm-mec-mutated or psm-mec-deleted HA-MRSAs, PSMα expression was increased compared with strains carrying intact psm-mec, and some mutated strains produced high amounts of PSMα comparable with that of CA-MRSA. Deletion of psm-mec from HA-MRSA strains carrying intact psm-mec increased the expression of AgrA protein and PSMα, and virulence in mice. Thus, psm-mec RNA suppresses MRSA virulence via inhibition of agrA translation and the absence of psm-mec function in CA-MRSA causes its high virulence property.

  11. Jornaleros agrícolas internacionales: Purépechas contratados H2-A en Estados Unidos

    OpenAIRE

    Casimiro Leco Tomás

    2014-01-01

    Se hace un análisis sobre el programa de trabajadores temporales que se contratan mediante el tipo de visas H2-A, para jornaleros agrícolas, quienes salen del medio rural del estado de Michoacán, México, particularmente de las comunidades indígenas Purépechas y cual su participación en las contrataciones, conexiones transfronterizas e impacto en México y Estados Unidos.

  12. Complex regulation of Arabidopsis AGR1/PIN2-mediated root gravitropic response and basipetal auxin transport by cantharidin-sensitive protein phosphatases

    Science.gov (United States)

    Shin, Heungsop; Shin, Hwa-Soo; Guo, Zibiao; Blancaflor, Elison B.; Masson, Patrick H.; Chen, Rujin

    2005-01-01

    Polar auxin transport, mediated by two distinct plasma membrane-localized auxin influx and efflux carrier proteins/complexes, plays an important role in many plant growth and developmental processes including tropic responses to gravity and light, development of lateral roots and patterning in embryogenesis. We have previously shown that the Arabidopsis AGRAVITROPIC 1/PIN2 gene encodes an auxin efflux component regulating root gravitropism and basipetal auxin transport. However, the regulatory mechanism underlying the function of AGR1/PIN2 is largely unknown. Recently, protein phosphorylation and dephosphorylation mediated by protein kinases and phosphatases, respectively, have been implicated in regulating polar auxin transport and root gravitropism. Here, we examined the effects of chemical inhibitors of protein phosphatases on root gravitropism and basipetal auxin transport, as well as the expression pattern of AGR1/PIN2 gene and the localization of AGR1/PIN2 protein. We also examined the effects of inhibitors of vesicle trafficking and protein kinases. Our data suggest that protein phosphatases, sensitive to cantharidin and okadaic acid, are likely involved in regulating AGR1/PIN2-mediated root basipetal auxin transport and gravitropism, as well as auxin response in the root central elongation zone (CEZ). BFA-sensitive vesicle trafficking may be required for the cycling of AGR1/PIN2 between plasma membrane and the BFA compartment, but not for the AGR1/PIN2-mediated root basipetal auxin transport and auxin response in CEZ cells.

  13. Copper stress induces a global stress response in Staphylococcus aureus and represses sae and agr expression and biofilm formation.

    Science.gov (United States)

    Baker, Jonathan; Sitthisak, Sutthirat; Sengupta, Mrittika; Johnson, Miranda; Jayaswal, R K; Morrissey, Julie A

    2010-01-01

    Copper is an important cofactor for many enzymes; however, high levels of copper are toxic. Therefore, bacteria must ensure there is sufficient copper for use as a cofactor but, more importantly, must limit free intracellular levels to prevent toxicity. In this study, we have used DNA microarray to identify Staphylococcus aureus copper-responsive genes. Transcriptional profiling of S. aureus SH1000 grown in excess copper identified a number of genes which fall into four groups, suggesting that S. aureus has four main mechanisms for adapting to high levels of environmental copper, as follows: (i) induction of direct copper homeostasis mechanisms; (ii) increased oxidative stress resistance; (iii) expression of the misfolded protein response; and (iv) repression of a number of transporters and global regulators such as Agr and Sae. Our experimental data confirm that resistance to oxidative stress and particularly to H2O2 scavenging is an important S. aureus copper resistance mechanism. Our previous studies have demonstrated that Eap and Emp proteins, which are positively regulated by Agr and Sae, are required for biofilm formation under low-iron growth conditions. Our transcriptional analysis has confirmed that sae, agr, and eap are repressed under high-copper conditions and that biofilm formation is indeed repressed under high-copper conditions. Therefore, our results may provide an explanation for how copper films can prevent biofilm formation on catheters.

  14. Influence of Sae-regulated and Agr-regulated factors on the escape of Staphylococcus aureus from human macrophages.

    Science.gov (United States)

    Münzenmayer, Lisa; Geiger, Tobias; Daiber, Ellen; Schulte, Berit; Autenrieth, Stella E; Fraunholz, Martin; Wolz, Christiane

    2016-08-01

    Although Staphylococcus aureus is not a classical intracellular pathogen, it can survive within phagocytes and many other cell types. However, the pathogen is also able to escape from cells by mechanisms that are only partially understood. We analysed a series of isogenic S. aureus mutants of the USA300 derivative JE2 for their capacity to destroy human macrophages from within. Intracellular S. aureus JE2 caused severe cell damage in human macrophages and could efficiently escape from within the cells. To obtain this full escape phenotype including an intermittent residency in the cytoplasm, the combined action of the regulatory systems Sae and Agr is required. Mutants in Sae or mutants deficient in the Sae target genes lukAB and pvl remained in high numbers within the macrophages causing reduced cell damage. Mutants in the regulatory system Agr or in the Agr target gene psmα were largely similar to wild-type bacteria concerning cell damage and escape efficiency. However, these strains were rarely detectable in the cytoplasm, emphasizing the role of phenol-soluble modulins (PSMs) for phagosomal escape. Thus, Sae-regulated toxins largely determine damage and escape from within macrophages, whereas PSMs are mainly responsible for the escape from the phagosome into the cytoplasm. Damage of macrophages induced by intracellular bacteria was linked neither to activation of apoptosis-related caspase 3, 7 or 8 nor to NLRP3-dependent inflammasome activation.

  15. La industria de maquinaria agrícola en Argentina frente a la estructura sectorial del mercado internacional

    Directory of Open Access Journals (Sweden)

    Federico Langard

    2011-01-01

    Full Text Available En el marco de una continua reestructuración de las empresas trasnacionales productoras de maquinaria agrícola a nivel mundial, se observa una, significativa tendencia a la concentración de las mismas y a la oligopolización de la oferta mundial, situación que sin lugar a dudas impacta en nuestro país. El trabajo analiza la dinámica del comercio mundial de maquinaria agrícola, vinculada al desempeño del sector en Argentina. Para ello, se examina el comportamiento de las firmas nacionales y extranjeras [radicadas y no radicadas en el país] a partir de su inserción internacional. Para mejorar el nivel de las observaciones, el amplio espectro del sector de maquinaria agrícola es dividido en diferentes subsectores según producto. Este diseño de investigación pone en evidencia las estrategias seguidas por el entramado de empresas locales y multinacionales, en el territorio local y regional, y se observan, de acuerdo a ello, variadas ventajas en los diferentes subsectores

  16. Use of an Immobilized Monoclonal Antibody to Examine Integrin &agr;5&bgr;1 Signaling Independent of Cell Spreading

    Directory of Open Access Journals (Sweden)

    Bao Wenjie

    2002-01-01

    Full Text Available Cell attachment to the extracellular matrix (ECM engages integrin signaling into the cell, but part of the signaling response also stem from cell spreading (3. To analyze specific integrin signaling-mediated responses independent of cell spreading, we developed a method engaging integrin signaling by use of an immobilized anti-integrin monoclonal antibody (mab directed against the fibronectin (FN receptor integrin &agr;5&bgr;1. ECV 304 cells were plated onto FN or immobilized mab JBS5 (anti-integrin &agr;5&bgr;1 or onto poly-L-lysin (P-L-L, which mediates integrin-independent attachment. Cells attached and spread on FN, while cells on JBS5 or P-L-L attached but did not spread. Importantly, plating onto FN or mab JBS5 gave rise to identical integrin-induced responses, including a down-regulation of the cyclin-dependent kinase (Cdk2 inhibitors p21CIP1 and p27KIP1, while attachment to P-L-L did not. We conclude that engagement of the FN-receptor integrin &agr;5&bgr;1 induces integrin signaling regulating the Cdk2-inhibitors independent of cell spreading and present a method for how integrin signaling can be analyzed separate from the effects of cell spreading.

  17. Daily Thermal Predictions of the AGR-1 Experiment with Gas Gaps Varying with Time

    Energy Technology Data Exchange (ETDEWEB)

    Grant Hawkes; James Sterbentz; John Maki; Binh Pham

    2012-06-01

    A new daily as-run thermal analysis was performed at the Idaho National Laboratory on the Advanced Gas Reactor (AGR) test experiment number one at the Advanced Test Reactor (ATR). This thermal analysis incorporates gas gaps changing with time during the irradiation experiment. The purpose of this analysis was to calculate the daily average temperatures of each compact to compare with experimental results. Post irradiation examination (PIE) measurements of the graphite holder and fuel compacts showed the gas gaps varying from the beginning of life. The control temperature gas gap and the fuel compact – graphite holder gas gaps were linearly changed from the original fabrication dimensions, to the end of irradiation measurements. A steady-state thermal analysis was performed for each daily calculation. These new thermal predictions more closely match the experimental data taken during the experiment than previous analyses. Results are presented comparing normalized compact average temperatures to normalized log(R/B) Kr-85m. The R/B term is the measured release rate divided by the predicted birth rate for the isotope Kr-85m. Correlations between these two normalized values are presented.

  18. Las actividades complementarias de las explotaciones agrícolas peruanas

    Directory of Open Access Journals (Sweden)

    2002-01-01

    Full Text Available La diversification des sources de revenu des exploitations agricoles est une question cruciale pour le bien être des populations rurales. En effet, toute utilisation supplémentaire du travail en milieu rural pour des activités autres que celles directement liées à l’exploitation agricole peut contribuer à augmenter les revenus, même modestement. Cet article montre que malgré le potentiel que représentent les activités complémentaires des exploitations agricoles tant en termes de création d’emplois que de revenus, elles sont encore un domaine peu compris de l’économie rurale. Cette faiblesse provient à la fois de l’hétérogénéité de ces activités qui est à la source de nombreuses confusions conceptuelles et des lacunes des statistiques nationales disponibles qui n’enregistrent pas ces activités de manière adéquate. En dépit de ces difficultés, cet article tente de donner un aperçu de l’importance et des caractéristiques des activités complémentaires des exploitations agricoles péruviennes. Quatre conclusions principales émergent de l’ensemble des résultats présentés : la sous-estimation indubitable de ces activités donc des revenus qui en découlent la part significative qu’occupe l’agriculture dans l’ensemble des activités complémentaires, la concentration de ces activités dans deux ou trois secteurs, la relative stabilité de leur distribution selon les secteurs dans le temps et dans l’espace, une division du travail assez marquée entre les hommes et les femmes. La diversificación de las fuentes de ingresos de las explotaciones agrícolas es un asunto crucial para el bienestar de las poblaciones rurales. De hecho, en el medio rural, todo trabajo adicional en actividades distintas a las directamente relacionadas con la explotación agrícola puede contribuir al aumento de los ingresos, aun en forma modesta. Este trabajo muestra que, pese a su potencial en términos de generación de empleos e

  19. Preliminary results of post-irradiation examination of the AGR-1 TRISO fuel compacts

    Energy Technology Data Exchange (ETDEWEB)

    Paul Demkowicz; John Hunn; Robert Morris; Jason Harp; Philip Winston; Charles Baldwin; Fred Montgomery; Scott Ploger; Isabella van Rooyen

    2012-10-01

    Five irradiated fuel compacts from the AGR-1 experiment have been examined in detail in order to assess in-pile fission product release behavior. Compacts were electrolytically deconsolidated and analyzed using the leach-burn-leach technique to measure fission product inventory in the compact matrix and identify any particles with a defective SiC layer. Loose particles were then gamma counted to measure the fission product inventory. One particle with a defective SiC layer was found in the five compacts examined. The fractional release of Ag 110m from the particles was significant. The total fraction of silver released from all the particles within a compact ranged from 0-0.63 and individual particles within a single compact often exhibited a very wide range of silver release. The average fractional release of Eu-154 from all particles in a compact was 2.4×10-4—1.3×10-2, which is indicative of release through intact coatings. The fractional Cs-134 inventory in the compact matrix was <2×10-5 when all coatings remained intact, indicating good cesium retention. Approximately 1% of the palladium inventory was found in the compact matrix for two of the compacts, indicating significant release through intact coatings.

  20. de la Ingeniería Agrícola en el mundo

    Directory of Open Access Journals (Sweden)

    Armando Eloy García de la Figal Costales

    2007-01-01

    Full Text Available A partir de las experiencias y tendencias modernas en el desarrollo de la enseñanza universitaria del Ingeniero Agrícola en el mundo, mediante los documentos emitidos por la American Society of Agricultural and Biological Engineers (ASABE del 2004 y la International Commission of Agricultural Engineering (CIGR de 1994 y del 2000, se analizan y precisan los principios e invariantes para la confección de los planes de estudio correspondientes, así como las limitaciones que representan para el proceso de enseñanza aprendizaje en las condiciones de Cuba. Se concluye que existen múltiples «perfiles terminales», los cuales, por la diversidad posible de asignaturas a cursar, tienen diferencias significativas y carreras diferentes, no quedando esclarecido sobre la base de qué principios pedagógicos y científicos se dividen y estructuran las asignaturas en grupos y «perfiles terminales», así como sus secuencias

  1. Centro Agrícola de la Institución Lauterhoten Alemania Federal

    Directory of Open Access Journals (Sweden)

    Haindl, Friedrich F.

    1974-06-01

    Full Text Available This article describes the installations of a farm to be used for the mentally retarded that are being treated in the Institution Lauterhofen in the vicinity. They consist of: a a block for garages for trucks, tractors and trailers; a slaughterhouse and a sausage factory; b another block with sheds for cows, calves and pigs, storeroom for potatoes and fodder; c a third building consisting of a complete flat and bedrooms for the staff. The three buildings described above occupy three and a half sides of a central working courtyard. The construction style and system are traditional and fulfill the intended function perfectly.En este artículo se describen las instalaciones de una granja agrícola para emplear a los retrasados mentales que son tratados en la Institución Lauterhofen, próxima a aquéllas. Se componen de: a un bloque destinado a garajes de camiones, tractores y remolques; matadero y chacinería; b otro con establos para vacas, terneras y cerdos; almacén de patatas y forraje; c un tercer edificio ocupado por una vivienda completa y dormitorios para empleados. Las tres construcciones reseñadas cierran tres lados y medio de un patio central de operaciones. El estilo y el sistema constructivo son tradicionales y definen perfectamente la función a realizar.

  2. Diversidad de especies alimenticias en tres mercados agrícolas de la Habana, Cuba

    Directory of Open Access Journals (Sweden)

    Tom\\u00E1s Shagarodsky

    2003-01-01

    Full Text Available Se realizó el inventario de la diversidad de especies vegetales presentes en el mercado de la Habana, Cuba, para mostrar el comportamiento de tres especies modelo: el mamey colorado o sapote (Pouteria sapota (Jacq. H. E. Moore et Stearn, especies del género Capsicum y el frijol caballero (Phaseolus lunatus L., en mercados de diferentes dimensiones, los cuales reciben productos agrícolas de localidades de todo el país. En las especies modelos se evaluaron su frecuencia de aparición, precio, procedencia, y otras características. Hubo hasta 74 especies ofertadas en un mismo día, de las cuales se aprecian numerosos cultivares tradicionales de granos, frutas y hortalizas entre otros usos. La cuantía de lo inventariado permite detectar en el transcurso de 12 meses de evaluación unas 276 especies comprendidas dentro de 84 familias. Se incluyen en el estudio las viandas, los vegetales, medicinales, granos, frutales y ornamentales. Se aprecia al comparar con los productos observados en estudios realizados en huertos caseros de todo el país, que sólo una pequeña parte de la diversidad apreciada en ellos llega al mercado.

  3. Structural characterization of native autoinducing peptides and abiotic analogues reveals key features essential for activation and inhibition of an AgrC quorum sensing receptor in Staphylococcus aureus.

    Science.gov (United States)

    Tal-Gan, Yftah; Ivancic, Monika; Cornilescu, Gabriel; Cornilescu, Claudia C; Blackwell, Helen E

    2013-12-11

    Staphylococcus aureus is a major human pathogen that uses quorum sensing (QS) to control virulence. Its QS system is regulated by macrocyclic peptide signals (or autoinducing peptides (AIPs)) and their cognate transmembrane receptors (AgrCs). Four different specificity groups of S. aureus have been identified to date (groups I-IV), each of which uses a different AIP:AgrC pair. Non-native ligands capable of intercepting AIP:AgrC binding, and thereby QS, in S. aureus have attracted considerable interest as chemical tools to study QS pathways and as possible antivirulence strategies for the treatment of infection. We recently reported a set of analogues of the group-III AIP that are capable of strongly modulating the activity of all four AgrC receptors. Critical to the further development of such ligands is a detailed understanding of the structural features of both native AIPs and non-native analogues that are essential for activity. Herein, we report the first three-dimensional structural analysis of the known native AIP signals (AIPs-I-IV) and several AIP-III analogues with varied biological activities using NMR spectroscopy. Integration of these NMR studies with the known agonism and antagonism profiles of these peptides in AgrC-III revealed two key structural elements that control AIP-III (and non-native peptide) activity: (1) a tri-residue hydrophobic "knob" essential for both activation and inhibition and (2) a fourth anchor point on the exocyclic tail needed for receptor activation. These results provide strong structural support for a mechanism of AIP-mediated AgrC activation and inhibition in S. aureus , and should facilitate the design of new AgrC ligands with enhanced activities (as agonists or antagonists) and simplified chemical structures.

  4. Comparison of fission product release predictions using PARFUME with results from the AGR-1 safety tests

    Energy Technology Data Exchange (ETDEWEB)

    Blaise Collin

    2014-09-01

    Safety tests were conducted on fourteen fuel compacts from AGR-1, the first irradiation experiment of the Advanced Gas Reactor (AGR) Fuel Development and Qualification program, at temperatures ranging from 1600 to 1800°C to determine fission product release at temperatures that bound reactor accident conditions. The PARFUME (PARticle FUel ModEl) code was used to predict the release of fission products silver, cesium, strontium, and krypton from fuel compacts containing tristructural isotropic (TRISO) coated particles during the safety tests, and the predicted values were compared with experimental results. Preliminary comparisons between PARFUME predictions and post-irradiation examination (PIE) results of the safety tests show different trends in the prediction of the fractional release depending on the species, and it leads to different conclusions regarding the diffusivities used in the modeling of fission product transport in TRISO-coated particles: • For silver, the diffusivity in silicon carbide (SiC) might be over-estimated by a factor of at least 102 to 103 at 1600°C and 1700°C, and at least 10 to 102 at 1800°C. The diffusivity of silver in uranium oxy-carbide (UCO) might also be over-estimated, but the available data are insufficient to allow definitive conclusions to be drawn. • For cesium, the diffusivity in UCO might be over-estimated by a factor of at least 102 to 103 at 1600°C, 105 at 1700°C, and 103 at 1800°C. The diffusivity of cesium in SiC might also over-estimated, by a factor of 10 at 1600°C and 103 at 1700°C, based upon the comparisons between calculated and measured release fractions from intact particles. There is no available estimate at 1800°C since all the compacts heated up at 1800°C contain particles with failed SiC layers whose release dominates the release from intact particles. • For strontium, the diffusivity in SiC might be over-estimated by a factor of 10 to 102 at 1600 and 1700°C, and 102 to 103 at 1800°C. These

  5. Mudanças na pauta das exportações agrícolas brasileiras

    Directory of Open Access Journals (Sweden)

    Maria Auxiliadora de Carvalho

    2008-03-01

    Full Text Available O trabalho visa contribuir para o debate sobre desindustrialização no Brasil, atribuída à apreciação cambial que, para vários autores, decorre do aumento das exportações agrícolas. Do emprego do método constant market share sobre informações de comércio exterior da FAO, para o período 1991-2003, chegou-se à conclusão que a exportação agrícola brasileira cresceu mais que o potencial, resultado de aumento expressivo da competitividade. Depois da mudança cambial, em 1999, parte da competitividade foi neutralizada pelo aumento da participação na pauta de produtos com demanda mundial em declínio. Da decomposição do valor exportado prevaleceu o efeito do aumento da quantidade, fato mais evidente depois da mudança cambial, porque o efeito preço foi negativo. Mesmo descontando o efeito da depreciação real do câmbio, a mudança nos preços internacionais foi desfavorável à agricultura brasileira. O efeito flexibilidade da pauta, negativo em todo o período, indica grande participação de produtos em desacordo com a lei geral da oferta, fato mais grave no período recente, quando a maior parte dos produtos com aumento do volume exportado estava com preço em baixa no mercado internacional. O declínio da exportação de manufaturados e o maior crescimento do comércio de produtos básicos indicam tendência à desindustrialização da agricultura.This paper aims to contribute to the Brazilian deindustrialization debate, attributed to exchange appreciation that, for several authors, is the agricultural export increase effect. Constant market share method applied on FAO export data, for the 1991 to 2003 period, indicates that Brazilian agricultural export increased more than the potential rate, due to expressive competitiveness gains. After the exchange regime change, in 1999, the competitiveness increase was partly neutralized by growth share of products whose world demand was in decline. Exports value decomposition showed

  6. Centro de investigaciones agrícolas en Saint-Aubin - Fribourg – Suiza

    Directory of Open Access Journals (Sweden)

    Zweifel, J.

    1974-03-01

    Full Text Available This Centre is made up of different installations, such as: management building, plant protection station, research centre, veterinary station, fodder centre and auxiliary exploitation, farm area, insulation station, entrance and dwellings, mill, slaughterhouse, etc. All the buildings, except the fodder tower, have only one floor —of differing heights— so that all communications are horizontal. The prefabricated reinforced concrete pillars rest on pile foundations and act as a support for the roof parts, which are U-shaped, and achieve cenital lighting and the due stability, as well as providing a characteristic physionomy and distinctive appearance of the whole.Este complejo está constituido por diversas instalaciones, tales como: edificio de administración, estación de protección de plantas, centro de investigación, estación veterinaria, centro de forrajes y explotación auxiliar, zona agrícola, estación de aislamiento, entrada y viviendas, molino, matadero, etcétera. Todos los edificios, salvo la torre de forraje, tienen una sola planta —de diferentes alturas—, a fin de que todas las comunicaciones sean horizontales. Los pilares prefabricados de hormigón armado se apoyan sobre cimentación de pilotes y sirven de soporte a las piezas de cubierta, en forma de U, que procuran iluminación cenital y la debida estabilidad, además de ofrecer una fisonomía característica y distintiva al conjunto.

  7. Fission Product Inventory and Burnup Evaluation of the AGR-2 Irradiation by Gamma Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Harp, Jason Michael [Idaho National Lab. (INL), Idaho Falls, ID (United States); Stempien, John Dennis [Idaho National Lab. (INL), Idaho Falls, ID (United States); Demkowicz, Paul Andrew [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2016-09-01

    Gamma spectrometry has been used to evaluate the burnup and fission product inventory of different components from the US Advanced Gas Reactor Fuel Development and Qualification Program's second TRISO-coated particle fuel irradiation test (AGR-2). TRISO fuel in this irradiation included both uranium carbide / uranium oxide (UCO) kernels and uranium oxide (UO2) kernels. Four of the 6 capsules contained fuel from the US Advanced Gas Reactor program, and only those capsules will be discussed in this work. The inventories of gamma-emitting fission products from the fuel compacts, graphite compact holders, graphite spacers and test capsule shell were evaluated. These data were used to measure the fractional release of fission products such as Cs-137, Cs-134, Eu-154, Ce-144, and Ag-110m from the compacts. The fraction of Ag-110m retained in the compacts ranged from 1.8% to full retention. Additionally, the activities of the radioactive cesium isotopes (Cs-134 and Cs-137) have been used to evaluate the burnup of all US TRISO fuel compacts in the irradiation. The experimental burnup evaluations compare favorably with burnups predicted from physics simulations. Predicted burnups for UCO compacts range from 7.26 to 13.15 % fission per initial metal atom (FIMA) and 9.01 to 10.69 % FIMA for UO2 compacts. Measured burnup ranged from 7.3 to 13.1 % FIMA for UCO compacts and 8.5 to 10.6 % FIMA for UO2 compacts. Results from gamma emission computed tomography performed on compacts and graphite holders that reveal the distribution of different fission products in a component will also be discussed. Gamma tomography of graphite holders was also used to locate the position of TRISO fuel particles suspected of having silicon carbide layer failures that lead to in-pile cesium release.

  8. Fission Product Inventory and Burnup Evaluation of the AGR-2 Irradiation by Gamma Spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Harp, Jason M.; Demkowicz, Paul A.; Stempien, John D.

    2016-11-01

    Gamma spectrometry has been used to evaluate the burnup and fission product inventory of different components from the US Advanced Gas Reactor Fuel Development and Qualification Program's second TRISO-coated particle fuel irradiation test (AGR-2). TRISO fuel in this irradiation included both uranium carbide / uranium oxide (UCO) kernels and uranium oxide (UO2) kernels. Four of the 6 capsules contained fuel from the US Advanced Gas Reactor program, and only those capsules will be discussed in this work. The inventories of gamma-emitting fission products from the fuel compacts, graphite compact holders, graphite spacers and test capsule shell were evaluated. These data were used to measure the fractional release of fission products such as Cs-137, Cs-134, Eu-154, Ce-144, and Ag-110m from the compacts. The fraction of Ag-110m retained in the compacts ranged from 1.8% to full retention. Additionally, the activities of the radioactive cesium isotopes (Cs-134 and Cs-137) have been used to evaluate the burnup of all US TRISO fuel compacts in the irradiation. The experimental burnup evaluations compare favorably with burnups predicted from physics simulations. Predicted burnups for UCO compacts range from 7.26 to 13.15 % fission per initial metal atom (FIMA) and 9.01 to 10.69 % FIMA for UO2 compacts. Measured burnup ranged from 7.3 to 13.1 % FIMA for UCO compacts and 8.5 to 10.6 % FIMA for UO2 compacts. Results from gamma emission computed tomography performed on compacts and graphite holders that reveal the distribution of different fission products in a component will also be discussed. Gamma tomography of graphite holders was also used to locate the position of TRISO fuel particles suspected of having silicon carbide layer failures that lead to in-pile cesium release.

  9. Examining the Quality of Life of Farmers with Disabilities: The Ohio AgrAbility Study.

    Science.gov (United States)

    Windon, S R; Jepsen, S D; Scheer, S D

    2016-01-01

    Quality of life is a broad concept that presents a challenge to measure as a scientific category. Quality of life encompasses a broad range of variables based on an individual's expression of life satisfaction, perceptions, values, feelings of subjective well-being, and happiness. This study identified and examined factors that influenced the quality of life of Ohio farmers with disabilities who were enrolled in the Ohio AgrAbility Program (OAP) (n = 55) and participated in this study (60% response rate). A 34-item questionnaire was created. The sample of OAP farmers reported stress many days a week, had a negative outlook on life, and were less satisfied with their overall quality of life because of their health. The OAP participants reported external factors, such as cost of equipment, financial pressures, and input costs, as having a negative effect on their quality of life. The participants also reported that they were not satisfied with the amount of vacation time (60.6%), managing farm work and family life (54.6%), overall health (55%), and quality of life (27%). The results showed a significant difference between the OAP participants' overall quality of life and the following variables: gender, net cash income, outlook on life, health, stress, farm work, managing farm and family, social activities, and emotional support for farmers with disabilities. The findings of this exploratory study allowed farmers to identify factors that they perceived as important to their quality of life. Moreover, the results may be helpful for stakeholders to better understand the needs of farmers with disabilities and provide appropriate educational and other services to enhance their quality of life.

  10. Evidence that the Agr-like quorum sensing system regulates the toxin production, cytotoxicity and pathogenicity of Clostridium perfringens type C isolate CN3685.

    Science.gov (United States)

    Vidal, Jorge E; Ma, Menglin; Saputo, Julian; Garcia, Jorge; Uzal, Francisco A; McClane, Bruce A

    2012-01-01

    Clostridium perfringens possesses at least two functional quorum sensing (QS) systems, i.e. an Agr-like system and a LuxS-dependent AI-2 system. Both of those QS systems can reportedly control in vitro toxin production by C. perfringens but their importance for virulence has not been evaluated. Therefore, the current study assessed whether these QS systems might regulate the pathogenicity of CN3685, a C. perfringens type C strain. Since type C isolates cause both haemorrhagic necrotic enteritis and fatal enterotoxemias (where toxins produced in the intestines are absorbed into the circulation to target other internal organs), the ability of isogenic agrB or luxS mutants to cause necrotizing enteritis in rabbit small intestinal loops or enterotoxemic lethality in mice was evaluated. Results obtained strongly suggest that the Agr-like QS system, but not the LuxS-dependent AI-2 QS system, is required for CN3685 to cause haemorrhagic necrotizing enteritis, apparently because the Agr-like system regulates the production of beta toxin, which is essential for causing this pathology. The Agr-like system, but not the LuxS-mediated AI-2 system, was also important for CN3685 to cause fatal enterotoxemia. These results provide the first direct evidence supporting a role for any QS system in clostridial infections.

  11. A point mutation in AgrC determines cytotoxic or colonizing properties associated with phenotypic variants of ST22 MRSA strains

    Science.gov (United States)

    Mairpady Shambat, Srikanth; Siemens, Nikolai; Monk, Ian R.; Mohan, Disha B.; Mukundan, Santhosh; Krishnan, Karthickeyan Chella; Prabhakara, Sushma; Snäll, Johanna; Kearns, Angela; Vandenesch, Francois; Svensson, Mattias; Kotb, Malak; Gopal, Balasubramanian; Arakere, Gayathri; Norrby-Teglund, Anna

    2016-01-01

    Methicillin-resistant Staphylococcus aureus (MRSA) is a major cause of skin and soft tissue infections. One of the highly successful and rapidly disseminating clones is MRSA ST22 commonly associated with skin tropism. Here we show that a naturally occurring single amino acid substitution (tyrosine to cysteine) at position 223 of AgrC determines starkly different ST22 S. aureus virulence phenotypes, e.g. cytotoxic or colonizing, as evident in both in vitro and in vivo skin infections. Y223C amino acid substitution destabilizes AgrC-AgrA interaction leading to a colonizing phenotype characterized by upregulation of bacterial surface proteins. The colonizing phenotype strains cause less severe skin tissue damage, show decreased susceptibility towards the antimicrobial LL-37 and induce autophagy. In contrast, cytotoxic strains with tyrosine at position 223 of AgrC cause infections characterized by inflammasome activation and severe skin tissue pathology. Taken together, the study demonstrates how a single amino acid substitution in the histidine kinase receptor AgrC of ST22 strains determines virulence properties and infection outcome. PMID:27511873

  12. Existence of two groups of Staphylococcus aureus strains isolated from bovine mastitis based on biofilm formation, intracellular survival, capsular profile and agr-typing.

    Science.gov (United States)

    Bardiau, Marjorie; Caplin, Jonathan; Detilleux, Johann; Graber, Hans; Moroni, Paolo; Taminiau, Bernard; Mainil, Jacques G

    2016-03-15

    Staphylococcus (S.) aureus is recognised worldwide as an important pathogen causing contagious acute and chronic bovine mastitis. Chronic mastitis account for a significant part of all bovine cases and represent an important economic problem for dairy producers. Several properties (biofilm formation, intracellular survival, capsular expression and group agr) are thought to be associated with this chronic status. In a previous study, we found the existence of two groups of strains based on the association of these features. The aim of the present work was to confirm on a large international and non-related collection of strains the existence of these clusters and to associate them with case history records. In addition, the genomes of eight strains were sequenced to study the genomic differences between strains of each cluster. The results confirmed the existence of both groups based on capsular typing, intracellular survival and agr-typing: strains cap8-positive, belonging to agr group II, showing a low invasion rate and strains cap5-positive, belonging to agr group I, showing a high invasion rate. None of the two clusters were associated with the chronic status of the cow. When comparing the genomes of strains belonging to both clusters, the genes specific to the group "cap5-agrI" would suggest that these strains are better adapted to live in hostile environment. The existence of these two groups is highly important as they may represent two clusters that are adapted differently to the host and/or the surrounding environment.

  13. Difference in agr dysfunction and reduced vancomycin susceptibility between MRSA bacteremia involving SCCmec types IV/IVa and I-III.

    Science.gov (United States)

    Jang, Hee-Chang; Kang, Seung-Ji; Choi, Su-Mi; Park, Kyung-Hwa; Shin, Jong-Hee; Choy, Hyon E; Jung, Sook-In; Kim, Hong Bin

    2012-01-01

    Dysfunction of agr, with reduced susceptibility or hetero-resistance to vancomycin, is thought to be associated with a worse outcome of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia (MRSAB). However, the difference in agr dysfunction according to the SCCmec type in MRSA infection is undetermined. We compared the prevalence of agr dysfunction, reduced vancomycin susceptibility and the outcomes of SCCmec IV/IVa and I-III MRSAB. The study included 307 cases of MRSAB. SCCmec types were determined by multiplex PCR. The clinical and microbiological features and outcomes of 58 SCCmec IV/IVa MRSAB were compared with those of 249 SCCmec I-III MRSAB. Compared with SCCmec I-III MRSAB, SCCmec IV/IVa MRSAB was associated with lower rates of agr dysfunction (3% vs. 43%), vancomycin minimum inhibitory concentration (MIC) = 2 µg/mL (3% vs. 15%), and hetero-resistance to vancomycin (0% vs. 8%) (all PIVa MRSAB were not different from those in patients with SCCmec I-III MRSAB in multivariate analyses (HR 1.168, 95% CI 0.705-1.938; HR 1.025, 95% CI 0.556-1.889). SCCmec IV/IVa MRSAB was associated with lower rates of agr dysfunction and hetero-resistance to vancomycin and a lower vancomycin MIC, compared with SCCmec I-III MRSAB. However, the outcomes of SCCmec IV/IVa MRSAB did not differ from those of SCCmec I-III MRSAB.

  14. La intervención en red para catalizar la innovación agrícola

    Directory of Open Access Journals (Sweden)

    Norman Aguilar Gallegos

    2017-05-01

    Full Text Available Se reconoce que los procesos de innovación suceden entre un conjunto heterogéneo de actores, donde el Análisis de Redes Sociales (ARS es una herramienta prometedora para su análisis y comprensión y, así, diseñar intervenciones basadas en red para catalizarla. Las intervenciones en red describen el proceso a través del cual se usan datos relacionales para acelerar el flujo de información entre los actores que la conforman. Este artículo contribuye en dos vertientes: primero, proporcionar conocimiento y evidencia sobre la aplicación y utilidad del ARS en el contexto de una intervención basada en red para catalizar la innovación agrícola; segundo, añadir a la literatura del ARS el estudio de una red al inicio y al final de la intervención de un programa de extensión, mostrando los cambios en la estructura e indicadores de forma longitudinal. Se utilizaron datos de productores caprinos para generar indicadores de línea base y después se analizó la intervención con una línea final. Los resultados sustentan la utilidad del ARS para catalizar la innovación agrícola, resaltando la importancia de la selección de agricultores y actores clave para dinamizar estos procesos. Se concluye con algunas implicaciones metodológicas y de política pública para mejorar e impulsar la innovación agrícola.

  15. Informe sobre Cuestiones Agrícolas de un Viaje a California y a Méjico

    Directory of Open Access Journals (Sweden)

    Navarro Ospina Francisco

    1939-12-01

    Full Text Available La magnitud de la industria agrícola, del Estado de California, es imposible de abarcarla y apreciarla. El éxito de la industria frutera de California se debe, a demás de las condiciones excepcionales de la región, a los cuidados que se tienen con los cultivos y en gran parte a la ayuda y protección dados por el Gobierno, valiéndose del Departamento de Agricultura y de las Estaciones Experimentales, las cuales le prestan toda dase de facilidades al agricultor; no sólo en aquello que se relaciona directamente con el cultivo, control de plagas y enfermedades, sino también fomentando la creación de cooperativas y asociaciones para la venta de los frutos. Entre las industrias agrícolas de Méjico, merecen mencionarse, por su adaptabilidad en nuestro medio, la de la cabuya y la fabricación de almidones. Estas industrias han dado sorprendentes resultados en aquel país y entre nosotros seguramente se obtendrán iguales resultados si para ello se pone un conato decidido y se presta eficaz ayuda. Es hora ya, de que nuestro gobierno y en especial el Ministerio de Agricultura, tome alguna iniciativa para impulsar una industria agrícola que indudablemente puede llegar a ser de grande importancia para el país, como lo ha sido en el Brasil y en otras regiones del globo, regiones cuyas condiciones ni son mejores ni ofrecen las perspectivas de clima y situación geográfica de Colombia.

  16. Huella hídrica de productos agrícolas producidos en la sierra central y comercializados en Lima

    Directory of Open Access Journals (Sweden)

    Tito Mallma Capcha

    2015-06-01

    Full Text Available El objetivo ha sido determinar un modelo para obtener la huella hídrica de los principales productos agrícolas de la sierra central del Perú que son comercializados en los mercados de la ciudad de Lima, para ello se desarrolló un modelo conceptual que determine el requerimiento de agua de los cultivos que junto a los respectivos rendimientos han permitido establecer el contenido de agua virtual de cada producto agrícola expresado en l/kg; con este resultado y la cantidad de producto comercializado, se han determinado el agua virtual (AV transferida hacia el mercado de Lima, correspondiente a los catorce productos agrícolas considerados. Se obtuvieron valores que indican que los volúmenes de agua virtual entre los productos varían por las cantidades comercializadas y están en función de la producción que a su vez depende de factores como el clima, la demanda del consumidor y de la tecnología empleada en la producción. Así, el consumo de un kg de papa en la ciudad de Lima implica la transferencia de 300,71 litros de “agua virtual” desde la región Junín, donde se produce el producto. El producto que transfiere la mayor cantidad de agua virtual es la papa con 78 069 926,37 m3, seguido de la arveja verde con 16 889 273,96 m3, y el producto que transfiere la menor cantidad es la cebolla con 10 336,59 m3, en tanto que el volumen total de agua virtual transferida es de 165 595 592,28 m3.

  17. Del hogar agrícola a los maestros queseros. La escuela granja de Tandil (Argentina, 1915-1960

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    Talía Violeta Gutiérrez

    2015-01-01

    Full Text Available La formación de recursos humanos y la generación de conocimientos adaptados a las condiciones de explotación de las diversas produccio-nes regionales en la Argentina ocuparon la atención de los técnicos del Ministerio de Agricultura de la Nación, de las entidades agraristas y de sectores políticos y educativos diversos desde inicios del siglo XX. No escapó a ese interés la preocupación por la mujer y el “hogar agrícola”. En el presente artículo fueron analizadas, en ese contexto, las primeras décadas de la Escuela Granja “Ramón Santamarina” de Tandil, un esta-blecimiento con una rica historia institucional que albergó la primera es-cuela del hogar agrícola del país, transformada pronto en granja-escuela y especializada en industria láctea. El tránsito del “hogar agrícola” a la preparación de maestros queseros -en el marco de la orientación productivista de las escuelas en la pro-puesta educativa del Ministerio-, los sujetos sociales involucrados, la es-pecialización en quesería y sus resultados, son algunas de las cuestiones analizadas. Esto se inserta en el contexto de un proyecto educativo agra-rio pensado no solo como fuente de mano de obra, vinculado a determi-nadas industrias agrarias, sino también –y tal vez más que nada– como irradiador de ese tipo de enseñanzas hacia la comunidad.

  18. Retrospectiva agroecológica a la interacción entre sistemas agrícolas tradicionales y modernos.

    Directory of Open Access Journals (Sweden)

    René Montalva

    2003-05-01

    Full Text Available En este trabajo se realiza un acercamiento desde la agroecología crítica a los orígenes y la expansión de la "agricultura moderna" y a su extensión hacia los sistemas agrícolas  tradicionales del tercer mundo. Asítambién, se analizan los efectos de esta transformación y de la adopción de las prácticas genéricas de la agricultura modema en los sistemas agrícolas familiares, principalmente campesinos e indígenas. Los antecedentes históricos recopilados ponen de manifisto que este proceso ha sido ampliamente desfavorable para los sistemas familiares, particulamente en aspectos económico -productivos, ambientales y sociales; encontrando el origen de gran parte de sus problemas actuales en la expansión de la "nueva agricultura" y en el modelo de desarrollo que hay tras ella. Con el respaldo de argumentos de tipo empírico y teóricos actuales, en este trabajo se concluye que, al igual que lo que ha ocurrido en otros lugares del planeta, la "rnodemización" de los sistemas agrícola familiares, con base tradicional, no dará solución al estado de pobreza material en la cual se encuentran campesinos e indígenas de los países del tercer mundo, sino que por el contrario producirá otros tipos de pobreza y problemas de diversa índole, muchos de ellos con efectos inciertos.

  19. Clusters agrícolas: un estado del arte para los estudios de competitividad en el campo

    Directory of Open Access Journals (Sweden)

    Lina Tapia

    2015-12-01

    Full Text Available En el siguiente trabajo se revisó cómo se ha abordado el fenómeno del cluster en la agricultura debido a que el encadenamiento entre eslabones de la producción y los modelos de gestión de sistemas agrícolas son cada vez más importantes para el equilibrio de mercado de los productos agroalimentarios, principalmente en un entorno que impulsa el crecimiento acelerado en la demanda de alimentos, bienes industriales y biocombustibles. Para tal propósito se discutió la relación entre agricultura, desarrollo rural, cadenas agroalimentarias y clusters agrícolas. Luego se seleccionaron trabajos de investigación internacionales y latinoamericanos que se ocuparon de caracterizar, medir o diseñar estos sistemas, con el fin de identificar variables, tipos de enfoques, métodos de estudio y principales aportes a la mejora de su productividad y competitividad. Al final, se encontró que los estudios de caso ad hoc han sido los métodos más aplicados, seguidos de los análisis multivariados y las tablas inputs-outputs. Además, se pudo ver que el enfoque cuantitativo a través de la simulación matemática, apenas comienza a incluirse en el problema de diseño de clusters agrícolas y que la preocupación por este tema en Latinoamérica también es reciente.

  20. Estructura económica nacional: breve análisis del sector agrícola ecuatoriano

    Directory of Open Access Journals (Sweden)

    Jorge González-Sarango

    2015-12-01

    Full Text Available La estructura económica del Ecuador se ha basado, tradicionalmente, en el sector agrícola, el cual enfrenta un panorama económico mundial desalentador. El actual, pero bajo, precio del petróleo, podría incentivar a los importadores de materias primas, pero a la vez complicaría la situación de los exportadores de productos agrícolas, especialmente en economías, como la ecuatoriana, que no cuentan con estrategias de mejora de los niveles de productividad ante el régimen de tipo de cambio flexible de las economías vecinas y de aquellas que demandan bienes nacionales, es decir, que no pueden devaluar la moneda, para compensar el impacto de las pérdidas en los términos de intercambio de la demanda, que genera el abaratamiento del petróleo. Por otra parte, la tasa de crecimiento de la economía ecuatoriana ha tenido que ser replanteada ante los cambios en el contexto mundial, lo cual puede significar, un retroceso en cuanto a la planeación estatal y la determinación del Presupuesto General del Estado para el 2016. En este escenario, el sector agrícola de Ecuador, se ve abocado a contribuir con un porcentaje –cada vez mayor– a la composición del Producto Interno Bruto, sin contar con incentivos ni mejoras dirigidas precisamente a impulsar este sector.

  1. Need for USA high level waste (HLW) alternate geological repository (AGR) and for a different methodology to enhance its acceptance

    Energy Technology Data Exchange (ETDEWEB)

    Levy, Salomon, E-mail: slevy112@aol.co [3425 South Bascom Avenue, Suite 225, Campbell, CA 95008 (United States)

    2010-10-15

    In early February 2010, the administration stopped work and withdrew the Department of Energy (DOE) application for a construction permit for the Yucca Mountain geological repository from the Nuclear Regulatory Commission (NRC). Also, a 'blue ribbon' Commission was appointed to explore alternatives for storage, processing, and disposal, including evaluation of advanced fuel cycles and to provide a final report in 24 months. That decision, however, failed to recognize that: (1) the U.S. will need an early alternate geological repository (AGR) for its HLW irrespective of the findings of the 'blue ribbon' Commission; (2) the once-through spent fuel inventory from commercial nuclear power reactors will continue to rise and so will the damages against the government for its failure to remove spent fuel from reactors sites, as specified in contracts; (3) there are prepackaged DOE and nuclear weapons HLW ready for shipment to a repository which must be taken into account because of government penalties for failure to do so; (4) the current Nuclear Waste Policy Act (NWPA) needs to be modified to allow the early search and approval of Alternate Geological Repository (AGR) and for an interim centralized HLW storage facility to reduce government liabilities; and (5) the methodology used to license Yucca Mountain needs to undergo serious modifications, including a different non-politicized management and siting credo. This paper reviews and discusses all the preceding shortcomings and proposes significant changes to pursue AGR as soon as possible and to get site approval by the NRC first under a formal, stepwise, well-structured risk-informed decision approach as recommended.

  2. Producción de Trichoderma viride en diferentes sustratos agrícolas

    OpenAIRE

    Amaro Leal, Luis; Romero Arenas, Omar; Rivera, T. A.; Huerta, L. M.

    2015-01-01

    Uno de los sustratos mayormente utilizados para reproducir a Trichoderma spp., es el grano entero de arroz, el cual tiene un costo relativamente alto en la producción de biofungicidas. Con el propósito de encontrar un sustrato económico y de fácil adquisición en la región de Tetela de Ocampo Puebla-México, en el cual la cepa nativa pueda presentar un buen desarrollo y una alta producción de esporas viables, se estableció esta investigación, que tuvo como objetivo evaluar 3 sustratos agríco...

  3. Proteomic and transcriptomic profiling of Staphylococcus aureus surface LPXTG-proteins: correlation with agr genotypes and adherence phenotypes.

    Science.gov (United States)

    Ythier, Mathilde; Resch, Grégory; Waridel, Patrice; Panchaud, Alexandre; Gfeller, Aurélie; Majcherczyk, Paul; Quadroni, Manfredo; Moreillon, Philippe

    2012-11-01

    Staphylococcus aureus infections involve numerous adhesins and toxins, which expression depends on complex regulatory networks. Adhesins include a family of surface proteins covalently attached to the peptidoglycan via a conserved LPXTG motif. Here we determined the protein and mRNA expression of LPXTG-proteins of S. aureus Newman in time-course experiments, and their relation to fibrinogen adherence in vitro. Experiments were performed with mutants in the global accessory-gene regulator (agr), surface protein A (Spa), and fibrinogen-binding protein A (ClfA), as well as during growth in iron-rich or iron-poor media. Surface proteins were recovered by trypsin-shaving of live bacteria. Released peptides were analyzed by liquid chromatography coupled to tandem mass-spectrometry. To unambiguously identify peptides unique to LPXTG-proteins, the analytical conditions were refined using a reference library of S. aureus LPXTG-proteins heterogeneously expressed in surrogate Lactococcus lactis. Transcriptomes were determined by microarrays. Sixteen of the 18 LPXTG-proteins present in S. aureus Newman were detected by proteomics. Nine LPXTG-proteins showed a bell-shape agr-like expression that was abrogated in agr-negative mutants including Spa, fibronectin-binding protein A (FnBPA), ClfA, iron-binding IsdA, and IsdB, immunomodulator SasH, functionally uncharacterized SasD, biofilm-related SasG and methicillin resistance-related FmtB. However, only Spa and SasH modified their proteomic and mRNA profiles in parallel in the parent and its agr- mutant, whereas all other LPXTG-proteins modified their proteomic profiles independently of their mRNA. Moreover, ClfA became highly transcribed and active in fibrinogen-adherence tests during late growth (24 h), whereas it remained poorly detected by proteomics. On the other hand, iron-regulated IsdA-B-C increased their protein expression by >10-times in iron-poor conditions. Thus, proteomic, transcriptomic, and adherence

  4. Certificación de eficiencia energética del edificio de Agrónomos

    OpenAIRE

    Rodríguez Vera, Cristina

    2015-01-01

    El trabajo pretende la expedición del certificado de eficiencia energética del edificio de la Escuela Técnica Superior de Ingeniería Agronómica, en adelante edificio de agrónomos, edificio existente de gran terciario. El certificado recogerá la documentación que contenga la información sobre las características energéticas y la calificación de eficiencia energética del citado. Se adjunta también un documento de recomendaciones para la mejora de los niveles óptimos de la eficien...

  5. Conversión y perspectivas del sector agrícola mexicano en el periodo 1980-2004.

    OpenAIRE

    Madrid Pérez, María Isabel

    2012-01-01

    En México se están dando cambios en la demanda de productos alimenticios con características específicas de acuerdo a la condición y circunstancia de los consumidores, lo cual, genera una reestructuración en la producción del sector agropecuario, si no hay restricciones o limitantes se espera que se produzca más de lo que más vale. En este trabajo se cuantifica el grado de conversión productiva para el sector agrícola mexicano en el periodo 1980-2004. El estudio abarca 110...

  6. Design and Status of the NGNP Fuel Experiment AGR-3/4 Irradiated in the Advanced Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Blaine Grover

    2012-10-01

    The United States Department of Energy’s Next Generation Nuclear Plant (NGNP) Advanced Gas Reactor (AGR) Fuel Development and Qualification Program will be irradiating up to seven separate low enriched uranium (LEU) tri-isotopic (TRISO) particle fuel (in compact form) experiments in the Advanced Test Reactor (ATR) located at the Idaho National Laboratory (INL). These irradiations and fuel development are being accomplished to support development of the next generation reactors in the United States, and will be irradiated over the next several years to demonstrate and qualify new TRISO coated particle fuel for use in high temperature gas reactors. The goals of the irradiation experiments are to provide irradiation performance data to support fuel process development, to qualify fuel for normal operating conditions, to support development and validation of fuel performance and fission product transport models and codes, and to provide irradiated fuel and materials for post irradiation examination (PIE) and safety testing. The experiments, which will each consist of at least six separate capsules, will be irradiated in an inert sweep gas atmosphere with individual on-line temperature monitoring and control of each capsule. The sweep gas will also have on-line fission product monitoring on its effluent to track performance of the fuel in each individual capsule during irradiation. The first experiment (designated AGR-1) started irradiation in December 2006 and was completed in November 2009. The second experiment (AGR-2) started irradiation in June 2010 and is currently scheduled to be completed in April 2013. The third and fourth experiments have been combined into a single experiment designated AGR-3/4, which started its irradiation in December 2011 and is currently scheduled to be completed in November 2013. Since the purpose of this experiment is to provide data on fission product migration and retention in the NGNP reactor, the design of this experiment is

  7. Estudi econòmic de l'oli de colza com a biocarburant en explotacions agrícoles

    OpenAIRE

    Baquero Armans, Grau; Esteban Dalmau, Bernat; Puig Vidal, Rita; Riba Ruiz, Jordi-Roger; Rius Carrasco, Antoni

    2010-01-01

    Actualment els biocarburants ocupen una important àrea d’estudi, essent el biodièsel i el bioetanol els més utilitzats en el nostre territori. La major part d’aquests biocarburants són de primera generació i la seva fabricació a gran escala presenta seriosos problemes ambientals i socials a causa de la gran demanda de terres agrícoles [1-2]. Tot i això, la necessitat de reduir l’emissió de gasos d’efecte hivernacle n’incrementa la seva demanda. Actualment, és interessant pensar en implemen...

  8. Prospectiva tecnológica y consideraciones curriculares en Ingeniería Agrícola

    OpenAIRE

    2011-01-01

    Los nuevos modelos económicos centrados en un mayor número de productos de exportación con un alto valor agregado hace necesario que se generen grandes desarrollos tecnológicos, en los cuales el papel de la Ingeniería es trascendental; para el caso de Ingeniería Agrícola se debe lograr importantes tecnificaciones del Sector Agropecuario para poder atender las demandas de productos alimenticios, para consumo interno y excedentes para otros países. Con el presente escrito se mostrará una visión...

  9. Funciones agua rendimiento para 14 cultivos agrícolas en condiciones del sur de La Habana

    OpenAIRE

    Felicita González Robaina; Julián Herrera Puebla; Teresa López Seijas; Greco Cid Lazo

    2013-01-01

    El estudio de las funciones agua rendimiento y su uso dentro de la planificación del uso del agua es una vía importante para trazar estrategias de manejo que contribuyan al incremento en la producción agrícola. Utilizando los datos de consumo de agua, agua aplicada por riego, precipitaciones y los rendimientos obtenidos en más de 100 experimentos de campo realizados fundamentalmente en suelo Ferralítico Rojo de la zona sur de La Habana y con ayuda de herramientas de análisis de regresión en e...

  10. Improving the AGR Fuel Testing Power Density Profile Versus Irradiation-Time in the Advanced Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Gray S. Chang; David A. Petti; John T. Maki; Misti A. Lillo

    2009-05-01

    The Very High Temperature gas-cooled Reactor (VHTR), which is currently being developed, achieves simplification of safety through reliance on ceramic-coated fuel particles. Each TRISO-coated fuel particle has its own containment which serves as the principal barrier against radionuclide release under normal operating and accident conditions. These fuel particles, in the form of graphite fuel compacts, are currently undergoing a series of irradiation tests in the Advanced Test Reactor (ATR) at the Idaho National Laboratory (INL) to support the Advanced Gas-Cooled Reactor (AGR) fuel qualification program. A representive coated fuel particle with an 235U enrichment of 19.8 wt% was used in this analysis. The fuel burnup analysis tool used to perform the neutronics study reported herein, couples the Monte Carlo transport code MCNP, with the radioactive decay and burnup code ORIGEN2. The fuel burnup methodology known as Monte-Carlo with ORIGEN2 (MCWO) was used to evaluate the AGR experiment assembly and demonstrate compliance with ATR safety requirements. For the AGR graphite fuel compacts, the MCWO-calculated fission power density (FPD) due to neutron fission in 235U is an important design parameter. One of the more important AGR fuel testing requirements is to maintain the peak fuel compact temperature close to 1250°C throughout the proposed irradiation campaign of 550 effective full power days (EFPDs). Based on the MCWO-calculated FPD, a fixed gas gap size was designed to allow regulation of the fuel compact temperatures throughout the entire fuel irradiation campaign by filling the gap with a mixture of helium and neon gases. The chosen fixed gas gap can only regulate the peak fuel compact temperature in the desired range during the irradiation test if the ratio of the peak power density to the time-dependent low power density (P/T) at 550 EFPDs is less than 2.5. However, given the near constant neutron flux within the ATR driver core and the depletion of 235U in

  11. Xi congreso nacional de ingeniería agrícola y áreas afines- conferencias magistrales

    OpenAIRE

    Facultad Nacional de Agronomía, Universidad Nacional de Colombia

    2013-01-01

    En este artículo podemos encontrar las conferencias magistrales de XI Congreso Nacional de Ingeniería Agrícola y Áreas Afines en el que se pueden encontrar las siguientes: Automatización en la industria azucarera de Brasil. Este texto presenta una historia resumida del desarrollo de la industria azucarera en Brasil, con énfasis en la producción de alcohol. Se muestra también, la composición de la matriz energética brasilera y la contribución de la energía proveniente de la biomasa, en especia...

  12. El Indice normalizado de vegetación como indicador de la sustentabilidad de un territorio agrícola

    OpenAIRE

    Zamar, José Luis

    2004-01-01

    Tesis (Magíster en Gestión Ambiental Agropecuaria)--UNC- Facultad de Ciencias Agropecuarias; U.N. de Río Cuarto- Facultad de Agronomía y Veterinaria, 2004. Se propuso evaluar de manera comparativa la sustentabilidad de diferentes ambientes agrícolas, utilizando la vegetación como un indicador dinámico de tal condición. Para ello se estudiaron los cambios temporales y la heterogeneidad espacial de un territorio a través de información satelital y se ensayaron d...

  13. Xi congreso nacional de ingeniería agrícola y áreas afines- conferencias magistrales

    OpenAIRE

    Facultad Nacional de Agronomía, Universidad Nacional de Colombia

    2013-01-01

    En este artículo podemos encontrar las conferencias magistrales de XI Congreso Nacional de Ingeniería Agrícola y Áreas Afines en el que se pueden encontrar las siguientes: Automatización en la industria azucarera de Brasil. Este texto presenta una historia resumida del desarrollo de la industria azucarera en Brasil, con énfasis en la producción de alcohol. Se muestra también, la composición de la matriz energética brasilera y la contribución de la energía proveniente de la biomasa, en especia...

  14. Caracterización de productores agrícolas de seis distritos de desarrollo rural de Zacatecas

    OpenAIRE

    Guillermo Galindo González; Wilfrido César Tabares Rodríguez; Guillermo Gómez Aguirre

    2000-01-01

    Con el propósito de caracterizar a los productores agrícolas de seis distritos de desarrollo rural de Zacatecas, en el segundo semestre de 1998 se realizó un estudio, en el cual se consideraron 10 variables relativas al productor y cinco a la unidad de producción. Para recopilar la información se aplicó un cuestionario integrado de 59 preguntas de tipo abierto y cerrado, a una muestra compuesta de 594 unidades muestrales, las cuales fueron seleccionadas aleatoriamente. Los resultados mostraro...

  15. Complexo teníase-cisticercose em assentamentos da Reforma Agrária do estado de Minas Gerais, Brasil

    OpenAIRE

    Acevedo Nieto, Emilio Campos

    2015-01-01

    Este é o primeiro estudo objetivando investigar a epidemiologia do complexo teníase- cisticercose, causado pelos parasitas Taenia solium e Taenia saginata, em assentamentos rurais da Reforma Agrária no Brasil. Para isto, 497 unidades de produção familiar foram selecionadas e amostradas aleatoriamente em 52 assentamentos do Estado de Minas Gerais. As amostras biológicas de 855 seres humanos, 1.533 bovinos e 518 suínos provenientes das referidas unidades foram coletadas e processadas. Além dest...

  16. AGR-1 Irradiated Test Train Preliminary Inspection and Disassembly First Look

    Energy Technology Data Exchange (ETDEWEB)

    Paul Demkowicz; Lance Cole; Scott Ploger; Philip Winston; Binh Pham; Michael Abbott

    2011-01-01

    The AGR-1 irradiation experiment ended on November 6, 2009, after 620 effective full power days in the Advanced Test Reactor, achieving a peak burnup of 19.6% FIMA. The test train was shipped to the Materials and Fuels Complex in March 2010 for post-irradiation examination. The first PIE activities included non-destructive examination of the test train, followed by disassembly of the test train and individual capsules and detailed inspection of the capsule contents, including the fuel compacts and the graphite fuel holders. Dimensional measurements of the compacts, graphite holders, and steel capsules shells were performed using a custom vision measurement system (for outer diameters and lengths) and conventional bore gauges (for inner diameters). Gamma spectrometry of the intact test train gave a preliminary look at the condition of the interior components. No evidence of damage to compacts or graphite components was evident from the isotopic and gross gamma scans. Neutron radiography of the intact Capsule 2 showed a high degree of detail of interior components and confirmed the observation that there was no major damage to the capsule. Disassembly of the capsules was initiated using procedures qualified during out-of-cell mockup testing. Difficulties were encountered during capsule disassembly due to irradiation-induced changes in some of the capsule components’ properties, including embrittled niobium and molybdenum parts that were susceptible to fracture and swelling of the graphite fuel holders that affected their removal from the capsule shells. This required various improvised modifications to the disassembly procedure to avoid damage to the fuel compacts. Ultimately the capsule disassembly was successful and only one compact from Capsule 4 (out of 72 total in the test train) sustained damage during the disassembly process, along with the associated graphite holder. The compacts were generally in very good condition upon removal. Only relatively minor

  17. Comparison of fission product release predictions using PARFUME with results from the AGR-1 irradiation experiment

    Energy Technology Data Exchange (ETDEWEB)

    Blaise Collin

    2014-09-01

    This report documents comparisons between post-irradiation examination measurements and model predictions of silver (Ag), cesium (Cs), and strontium (Sr) release from selected tristructural isotropic (TRISO) fuel particles and compacts during the first irradiation test of the Advanced Gas Reactor program that occurred from December 2006 to November 2009 in the Advanced Test Reactor (ATR) at Idaho National Laboratory (INL). The modeling was performed using the particle fuel model computer code PARFUME (PARticle FUel ModEl) developed at INL. PARFUME is an advanced gas-cooled reactor fuel performance modeling and analysis code (Miller 2009). It has been developed as an integrated mechanistic code that evaluates the thermal, mechanical, and physico-chemical behavior of fuel particles during irradiation to determine the failure probability of a population of fuel particles given the particle-to-particle statistical variations in physical dimensions and material properties that arise from the fuel fabrication process, accounting for all viable mechanisms that can lead to particle failure. The code also determines the diffusion of fission products from the fuel through the particle coating layers, and through the fuel matrix to the coolant boundary. The subsequent release of fission products is calculated at the compact level (release of fission products from the compact) but it can be assessed at the particle level by adjusting the diffusivity in the fuel matrix to very high values. Furthermore, the diffusivity of each layer can be individually set to a high value (typically 10-6 m2/s) to simulate a failed layer with no capability of fission product retention. In this study, the comparison to PIE focused on fission product release and because of the lack of failure in the irradiation, the probability of particle failure was not calculated. During the AGR-1 irradiation campaign, the fuel kernel produced and released fission products, which migrated through the successive

  18. Performance of AGR-1 high-temperature reactor fuel during post-irradiation heating tests

    Energy Technology Data Exchange (ETDEWEB)

    Morris, Robert N., E-mail: morrisrn@ornl.gov [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6093 (United States); Baldwin, Charles A. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6093 (United States); Demkowicz, Paul A. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415 (United States); Hunn, John D. [Oak Ridge National Laboratory, P.O. Box 2008, Oak Ridge, TN 37831-6093 (United States); Reber, Edward L. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83415 (United States)

    2016-09-15

    Highlights: • High-temperature safety tests were performed on 14 irradiated HTGR fuel compacts. • Significant krypton release was detected in only one of the safety tests. • Cesium retention by intact SiC was excellent, even up to 1800 °C. • Release of Ag, Eu, and Sr was dominated by previous release during irradiation. • Silver exhibited the highest fractional release. - Abstract: The fission product retention of irradiated low-enriched uranium oxide/uranium carbide tri-structural isotropic (TRISO) fuel compacts from the Advanced Gas-Cooled Reactor 1 (AGR-1) experiment has been evaluated at temperatures of 1600–1800 °C during post-irradiation safety tests. Fourteen compacts (a total of ∼58,000 particles) with a burnup ranging from 13.4% to 19.1% fissions per initial metal atom (FIMA) have been tested using dedicated furnace systems at Idaho National Laboratory and Oak Ridge National Laboratory. The release of fission products {sup 110m}Ag, {sup 134}Cs, {sup 137}Cs, {sup 154}Eu, {sup 155}Eu, {sup 90}Sr, and {sup 85}Kr was monitored while heating the fuel specimens in flowing helium. The behavior of silver, europium, and strontium appears to be dominated by inventory that was originally released through intact SiC coating layers during irradiation, but was retained in the compact at the end of irradiation and subsequently released during the safety tests. However, at a test temperature of 1800 °C, the data suggest that release of these elements through intact coatings may become significant after ∼100 h. Cesium was very well retained by intact SiC layers, with a fractional release <5 × 10{sup −6} after 300 h at 1600 °C or 100 h at 1800 °C. However, it was rapidly released from individual particles if the SiC layer failed, and therefore the overall cesium release fraction was dominated by the SiC defect and failure fractions in the fuel compacts. No complete TRISO coating layer failures were observed after 300 h at 1600 or 1700 °C, and {sup

  19. Performance of AGR-1 High-Temperature Reactor Fuel During Post-Irradiation Heating Tests

    Energy Technology Data Exchange (ETDEWEB)

    Morris, Robert Noel [ORNL; Baldwin, Charles A [ORNL; Hunn, John D [ORNL; Demkowicz, Paul [Idaho National Laboratory (INL); Reber, Edward [Idaho National Laboratory (INL)

    2014-01-01

    The fission product retention of irradiated low-enriched uranium oxide/uranium carbide TRISO fuel compacts from the AGR-1 experiment has been evaluated at temperatures of 1600 1800 C during post-irradiation safety tests. Fourteen compacts (a total of ~58,000 particles) with a burnup ranging from 13.4 to 19.1% FIMA have been tested using dedicated furnace systems at Idaho National Laboratory and Oak Ridge National Laboratory. The release of fission products 110mAg, 134Cs, 137Cs, 154Eu, 155Eu, 90Sr, and 85Kr was monitored while heating the fuel specimens in flowing helium. The behavior of silver, europium, and strontium appears to be dominated by inventory that was originally released through intact SiC coating layers during irradiation, but was retained in the compact at the end of irradiation and subsequently released during the safety tests. However, at a test temperature of 1800 C, the data suggest that release of these elements through intact coatings may become significant after ~100 h. Cesium was very well retained by intact SiC layers, with a fractional release <5 10-6 after 300 h at 1600 C or 100 h at 1800 C. However, it was rapidly released from individual particles if the SiC layer failed, and therefore the overall cesium release fraction was dominated by the SiC defect and failure fractions in the fuel compacts. No complete TRISO coating layer failures were observed after 300 h at 1600 or 1700 C, and 85Kr release was very low during the tests (particles with breached SiC, but intact outer pyrocarbon, retained most of their krypton). Krypton release from TRISO failures was only observed after ~210 h at 1800 C in one compact. Post-safety-test examination of fuel compacts and particles has focused on identifying specific particles from each compact with notable fission product release and detailed analysis of the coating layers to understand particle behavior.

  20. Regadíos agrícolas, territorio y desarrollo rural

    Directory of Open Access Journals (Sweden)

    Moyano Estrada, Eduardo

    2008-02-01

    Full Text Available This article analyses how the topics linked to water management have changed in social perception and political agenda in Spain. From a hydraulic and agricultural-oriented logic it has shifted toward other more integral and multifunctional one, where the Ministry of Environment is the most relevant player. In such a social and political context, the new orientations of rural development policies are analysed, particularly in relation to the sustainable management of water resources in farming sector and their implications on territory. The authors propose a typology of irrigable areas in Spain, and analyse the process of implementation of the new European Regulation on Rural Development (Reg. 1690/2005. The conclusion is that this new policy could be a useful tool to promote the environmental sustainability of these areas only if there was a good coordination between agricultural and environmental departments at the regional level.En este artículo se analiza la percepción social y política de los temas relacionados con la gestión del agua en España, mostrando cómo se ha pasado de una lógica hidráulica y sectorial (agraria, canalizada a través de los ministerios de Obras Públicas y Agricultura, a otra integral y multifuncional, en la que se valoran sus implicaciones territoriales y en la que asume protagonismo el ministerio de Medio Ambiente. En ese contexto, se analizan las nuevas orientaciones de las políticas de desarrollo rural, especialmente en lo relacionado con la gestión sostenible de los recursos hídricos en la agricultura y sus efectos sobre el territorio. La diversidad del regadío agrícola en España es analizada por los autores, proponiendo una tipología de zonas regables con problemas de eficiencia, y valorando en qué medida las acciones contempladas en el nuevo Reglamento europeo de Desarrollo Rural (FEADER pueden ser un instrumento útil para avanzar en la sostenibilidad ambiental de dichas áreas. La conclusi

  1. Solo agrícola e agricultura em espaço urbano: dinâmicas. O exemplo de Évora

    Directory of Open Access Journals (Sweden)

    Maria Freire

    2014-12-01

    Full Text Available O objetivo do artigo é melhorar o entendimento sobre o significado da componente agrícola em espaço urbano para as sociedades e perspetivar estratégias no sentido de promover o património solo agrícola e a permanência e sustentabilidade do uso agrícola em espaço urbano. A metodologia de trabalho seguida compreende a análise da dinâmica de evolução urbana, associada à presença da agricultura em espaço urbano em Évora, numa perspetiva que inclui o seu significado nos domínios históricos, sociais, económicos, ecológicos e estéticos.

  2. Eficiência de produção segundo diferentes mecanismos de acesso à terra na reforma agrária brasileira

    OpenAIRE

    Magalhães, Marcelo Marques de [UNESP

    2011-01-01

    A reforma agrária permanece um tema atual em função das tensões provocadas pela concentração de terras e pela falta de alternativas de ocupação para parte da população que ainda vive no meio rural. Ao transferir terras improdutivas para famílias com potencial produtivo, a reforma agrária pode aumentar a eficiência econômica. O modelo de reforma agrária brasileiro, baseia-se no assentamento de famílias sem terra, em terras devolutas ou desapropriadas de imóveis improdutivos. Os programas de ac...

  3. Reestructuración agrícola de las familias productoras de maíz: estudio en San Mateo Ayecac, Tlaxcala, 2000-2008.

    Directory of Open Access Journals (Sweden)

    Ma. Concepción Alvarado Méndez

    2011-01-01

    Full Text Available La investigación tiene por objetivo analizar el mecanismo de transformación agrícola expresado en los cambios de la fuerza de trabajo agrícola en términos de su estructura económica así como las principales consecuencias económicas en la comunidad de San Mateo Ayecac, municipio de Tepetitla en el estado de Tlaxcala. Los resultados muestran una transformación de las familias productoras de granos básicos, expresados en el proceso productivo, específicamente en la disminución de labores, fertilización, disminución del trabajo familiar y en el rendimiento. A pesar de ello no existe abandono de la actividad agrícola y sigue siendo la base de la alimentación familiar y un importante abastecedor de alimentos de los mercados locales.

  4. Optimização da Gestão do Parque de Máquinas da Sociedade Agrícola do Rabaço

    OpenAIRE

    Abelho, Simão Manuel de Ascenção

    2009-01-01

    Foi realizada a caracterização do parque de máquinas e a sua utilização no plano cultural, no ano agrícola de 2008/2009, na Sociedade Agrícola do Rabaço, Lda., cuja exploração agrícola se situa no concelho de Avis (Alto Alentejo). Verificou-se que face ao plano cultural de 2008/2009, e que se perspectiva que venha a ser o mesmo nos próximos anos, o parque de máquinas está sobredimensionado, contando com uma frota de 3 tractores de grande potência (150 cv, 130 cv e 105 cv) que, no conjunto,...

  5. Mecanización agrícola, empleo y migración en el norte de Tamaulipas

    Directory of Open Access Journals (Sweden)

    José Luis Contreras Valenzuela

    1986-05-01

    Full Text Available El objetivo del presente trabajo es analizar el modelo de desarrollo agrícola recientemente adoptado en los distritos de riego del norte de Tamaulipas, y los efectos sobre el empleo y la migración de la población rural. Dicho análisis se efectuará a partir de dos premisas fundamentales: una de ellas es la internacionalización del proceso productivo que se manifiesta con la presencia de una nueva división internacional del trabajo y lo que en este ensayo es llamada economía campesina, que fue la fuente primaria de la acumulación de capital de la agricultura mexicana, la cual jugará un papel importante para la acumulación de capital de la agricultura de los Estados Unidos de América, mediante la oferta de fuerza de trabajo agrícola barata, permitiendo el desarrollo de la agricultura comercial, modelo que ahora se ha volcado sobre la economía campesina condenándola a su desaparición como forma de subsistencia de la población rural, a quien expulsa de sus unidades de producción mediante el acaparamiento y el rentismo.

  6. Contaminación y control de las quemas agrícolas en Imperial, California, y Mexicali, Baja California

    Directory of Open Access Journals (Sweden)

    Margarito Quintero Núñez

    2008-01-01

    Full Text Available La quema de residuos agrícolas en los valles de Mexicali e Imperial, separados por una línea divisoria, constituye una fuente importante de emisión de contaminantes al aire, de compuestos como el metano (CH4, monóxido de carbono (CO, bióxido de nitrógeno (NO2, hidrocarburos (NMHC y partículas menores a 10 micras (PM10. Para abordar el problema de los humos agrícolas se debe considerar la cuenca atmosférica común, formada por ambos valles, que comparten un clima extremoso cálido y seco, con menos de 80 mm anuales de lluvia, y basan su economía en la agricultura, y el de Mexicali además en la industria manufacturera y otras actividades. En Mexicali, lo que se quema es sobre todo residuos de trigo y en menor proporción de cebada, cártamo y maíz. Los daños a la salud ocasionados por las emisiones de PM10 son significativos en ambos valles

  7. Potencial de biodegradación de DDT y sus metabolitos en suelos agrícolas de Chinandega

    Directory of Open Access Journals (Sweden)

    Carlos E. Noguera Solís

    2008-04-01

    Full Text Available LA PRESENTE INVESTIGACIÓN EVALUÓ EL POTENCIAL DE BIODEGRADACIÓN DEL 1,1,1-Tricloro- 2,2-bis(4-clorofeniletano (DDT y sus metabolitos en suelos agrícolas pertenecientes a fincas del municipio de El Viejo, Chinandega, a través de dos ensayos: ensayo de biodegradación ex situ y ensayo de búsqueda e identificación de microorganismos capaces de biodegradar DDT. En el primer ensayo se determinó el porcentajede biodegradación, bajo condiciones idóneas, durante un período de 100 días en diferentes lotes de suelo con diferentes aditivos (cachaza y estiércol a través de la aplicación de cepas microbianas comerciales Environoc 201®. De ello se obtuvo como resultado un porcentaje de biodegradación mayor para el lote que no presentaba aditivos orgánicos, siendo éste de 23,92%. En el ensayo de búsqueda eidentificación de bacterias se lograron aislar e identificar cepas microbianas nativas de los suelos agrícolas objeto de estudio utilizando medios de cultivo con DDT como única fuente de carbono y energía. Como resultado se lograron identificar los siguientes microorganismos: Pseudomonas sp., Streptomyces sp., Phanerochaetechrysosporium y levaduras.

  8. Modernização da Agricultura em Moçambique: determinantes da renda agrícola

    Directory of Open Access Journals (Sweden)

    Carlos E. Guanziroli

    2015-03-01

    Full Text Available O objetivo deste trabalho é verificar até que ponto as tecnologias oriundas da revolução verde foram efetivamente adotadas na África Subsaariana e, nos casos em que foram adotadas, se tiveram sucesso em melhorar a renda e a produtividade da agricultura. Para este fim, o trabalho faz primeiramente um breve resumo do estado das artes da revolução verde na África, mostrando quais países avançaram mais e como se correlaciona a utilização de fertilizantes químicos com os aumentos de produtividade. Faz-se também uma discussão sobre as características do processo de intensificação num caso em particular, o de Moçambique. Finalmente, com base nos microdados do Tratado de Inquérito Agrícola (TIA, se testa um modelo econométrico de MQO que visa avaliar os determinantes da renda agrícola e, em particular, do uso de fertilizantes químicos.

  9. Convergencia espacial y concentración regional agrícola en México 1970-2003

    Directory of Open Access Journals (Sweden)

    Normand Eduardo Asuad Sanén

    2007-01-01

    Full Text Available El propósito de este trabajo es analizar la relación entre convergencia tradicional y espacial del ingreso según la concentración regional de la producción agrícola de México, destacando los efectos propiciados por el cambio del modelo de desarrollo y gestión, mediante la liberalización y privatización de la economía con su incorporación al TLCAN y su comparación con el periodo 1970-2004. Se identifican y delimitan las regiones agrícolas a las que se aplica la medición econométrica de las hipótesis de convergencia tradicional, espacial y de la concentración económica. Los resultados confirman la tendencia a la disparidad del ingreso de esas regiones y el papel de la concentración económica como determinante de su comportamiento, asociado a la política de apertura de la economía mexicana.

  10. La sucesión "mortis causa" en la explotación agrícola familiar

    Directory of Open Access Journals (Sweden)

    José Luis De Los Mozos

    2015-01-01

    Full Text Available Llevo nada menos que cuarenta años dando vueltas al tema de la sucesión mortis causa en el Derecho agrario y más concretamente, al de la sucesión en la explotación agrícola. Esto no constituye ningún mérito, naturalmente, no es más que una mera circunstancia que acredita, cuando mucho, la firmeza de una convicción. Durante este tiempo, con mayor o menor contacto con la realidad social, he seguido y sigo fiel a mis puntos de vista originarios; no es que nada haya cambiado en todos estos años, sino que ha cambiado casi todo.Pero es que las soluciones que me parecían entonces muy dudosas, ahora me parecen inadmisibles.La evolución económica y social, ha puesto de relieve que las ideas que se utilizaban hace medio siglo en la materia, actualmente han quedado obsoletas (...Contenido: Una distinción obligada y un recuerdo inevitable. El recurso a la atribución preferente. Las condicionantes de la atribución preferente. El concepto de explotación agrícola. La reforma del derecho sucesorio como recapitulación

  11. Ablation de ZnO par laser UV (193 nm) : nano-agrégats en phase gazeuse

    Science.gov (United States)

    Ozerov, I.; Bulgakov, A.; Nelson, D.; Castell, R.; Sentis, M.; Marine, W.

    2003-06-01

    La condensation de nano-agrégats d'oxyde de zinc en phase gazeuse est mise en évidence lors de l'ablation de ZnO massif par laser ArF pulsé. Nous comparons l'évolution spatio-temporelle de la forme du panache d'ablation (plume) de ZnO sous vide et sous atmosphère de gaz de couverture (oxygène et/ou hélium) à partir des images CCD et des résultats issus d'analyses spectroscopiques. L'expansion du plasma et la croissance des nano-clusters sont influencées par l'effet du confinement de la plume dû aux collisions entre les particules ablatées et les molécules de gaz ambiant ainsi que par les réactions chimiques dans le cas de l'oxygène. Le spectre de rayonnement du plasma est constitué principalement par l'émission d'atomes excités de Zn neutre. Nous avons observé la photoluminescence des nano-agrégats en suspension dans le gaz ainsi que leur décomposition par laser ArF.

  12. Mecanización agrícola ¿Deterioro o conservación del suelo?

    Directory of Open Access Journals (Sweden)

    Armando Alvarado Chaves

    2006-05-01

    Full Text Available “Mecanización agrícola; ¿Deterioro o conservación del suelo?” trata sobre el mito de que la mecanización o preparación de los suelos, en forma mecánica, es el detonante del deterioro de los suelos por erosión sobre todo por erosión hídrica y en menor grado por erosión eólica. La erosión de los suelos puede ser de poca o de gran magnitud, dependiendo de cuatro factores, los cuales se analizan como errores que se cometen en el momento de preparar los suelos. Estos errores son, en realidad, los causantes del deterioro de los suelos por erosión y no la mecanización, ya que esta, bien planificada y aplicada, puede incluso servir para la conservaciónde los suelos y el medio ambiente. También se describen los implementos agrícolas que pueden usarse para reducir la erosión de los suelos, citando su forma de trabajo y algunas de las ventajas del uso de esos implementos.

  13. Pentose sugars inhibit metabolism and increase expression of an AgrD-type cyclic pentapeptide in Clostridium thermocellum

    Science.gov (United States)

    Verbeke, Tobin J.; Giannone, Richard J.; Klingeman, Dawn M.; Engle, Nancy L.; Rydzak, Thomas; Guss, Adam M.; Tschaplinski, Timothy J.; Brown, Steven D.; Hettich, Robert L.; Elkins, James G.

    2017-01-01

    Clostridium thermocellum could potentially be used as a microbial biocatalyst to produce renewable fuels directly from lignocellulosic biomass due to its ability to rapidly solubilize plant cell walls. While the organism readily ferments sugars derived from cellulose, pentose sugars from xylan are not metabolized. Here, we show that non-fermentable pentoses inhibit growth and end-product formation during fermentation of cellulose-derived sugars. Metabolomic experiments confirmed that xylose is transported intracellularly and reduced to the dead-end metabolite xylitol. Comparative RNA-seq analysis of xylose-inhibited cultures revealed several up-regulated genes potentially involved in pentose transport and metabolism, which were targeted for disruption. Deletion of the ATP-dependent transporter, CbpD partially alleviated xylose inhibition. A putative xylitol dehydrogenase, encoded by Clo1313_0076, was also deleted resulting in decreased total xylitol production and yield by 41% and 46%, respectively. Finally, xylose-induced inhibition corresponds with the up-regulation and biogenesis of a cyclical AgrD-type, pentapeptide. Medium supplementation with the mature cyclical pentapeptide also inhibits bacterial growth. Together, these findings provide new foundational insights needed for engineering improved pentose utilizing strains of C. thermocellum and reveal the first functional Agr-type cyclic peptide to be produced by a thermophilic member of the Firmicutes. PMID:28230109

  14. Determinación de la adsorción de cadmio mediante isotermas de adsorción en suelos agrícolas venezolanos

    OpenAIRE

    2012-01-01

    El cadmio es un metal pesado que tiende a acumularse en la superficie del suelo. En los últimos años, las actividades antropogénicas han ocasionado un incremento en los niveles de este metal en suelos agrícolas generando gran preocupación ambiental debido a su movilidad y lixiviación en el perfil del suelo y a la facilidad con que es absorbido por las plantas. El objetivo de este trabajo fue determinar la capacidad de adsorción de cadmio, de cuatro suelos venezolanos de uso agrícola con difer...

  15. O impacto da crise fiscal brasileira dos anos 80 no crédito rural: mecanismos e instrumentos alternativos de financiamento agrícola

    OpenAIRE

    Oliveira, Jader José de

    2010-01-01

    O corpus desta pesquisa consiste em detectar as transformações que teriam ocorrrido no financiamento agrícola a partir dos anos 80, tomando-se como fundamental o pressuposto de que o agravamento da crise fiscal brasileira a partir da década passada contribuiu, não apenas para diminuir o montante dos recursos para os financiamentos agrícolas, como também para estimular a criação de um novo modelo de crédito rural.

  16. Morbilidad laboral en el sector agrícola en trabajadores afiliados a una administradora de riesgos laborales (ARL) de Colombia, durante el periodo 2011-2012.

    OpenAIRE

    Velásquez Bueno, Diana Marcela

    2013-01-01

    Este estudio muestra la prevalencia por enfermedad laboral de un grupo de trabajadores afiliados a una ARL en Colombia. Compara la morbilidad laboral entre dos grupo de trabajadores expuestos y no expuestos al trabajo agrícola y al interior del grupo de trabajadores agrícolas agrupados en las actividades de corte de caña, cultivo de banano y flores. Se realizó un estudio descriptivo de tipo transversal durante el periodo 2011-2012, mediante la revisión de una base de datos de morbilidad la...

  17. Determinación de la adsorción de cadmio mediante isotermas de adsorción en suelos agrícolas venezolanos

    OpenAIRE

    Nereida Sánchez; Neudis Subero; Carmen Rivero

    2011-01-01

    El cadmio es un metal pesado que tiende a acumularse en la superficie del suelo. En los últimos años, las actividades antropogénicas han ocasionado un incremento en los niveles de este metal en suelos agrícolas generando gran preocupación ambiental debido a su movilidad y lixiviación en el perfil del suelo y a la facilidad con que es absorbido por las plantas. El objetivo de este trabajo fue determinar la capacidad de adsorción de cadmio, de cuatro suelos venezolanos de uso agrícola con difer...

  18. Migración internacional, actividades agrícolas y distribución del ingreso en una comunidad oaxaqueña, México

    OpenAIRE

    2012-01-01

    Este trabajo explora el efecto que tiene la migración internacional y las remesas sobre las actividades agrícolas y la distribución del ingreso en una comunidad indígena que recientemente ha masificado su migración internacional. Se emplearon modelos para relacionar variables agrícolas contra factores productivos, socio demográficos y de financiamiento a la migración en el hogar, asimismo, la descomposición del coeficiente de Gini se utilizó para determinar el efecto que tienen las fuentes de...

  19. Ús de l'oli vegetal cru com a biocarburant per autoconsum agrícola: avaluacio de la sostenibilitat del sistema a Catalunya

    OpenAIRE

    Baquero Armans, Grau

    2011-01-01

    La introducció de la colza en la rotació de conreus i la producció i ús d’oli vegetal cru (OVC) com a biocarburant per autoconsum agrícola presenten alguns avantatges respecte al sistema tradicional de conreu de la Catalunya central, com una major productivitat i la capacitat d’autoabastament de combustible. El principal objectiu d’aquesta tesi és estudiar la viabilitat ambiental i econòmica de l’autoconsum d’oli vegetal cru en una explotació agrícola. També es planteja l’avalu...

  20. Efectos del TLCAN sobre el empleo de mano de obra en el sector agrícola de México.

    OpenAIRE

    Lechuga Jardínez, Yuliana

    2013-01-01

    En 1994 el TLCAN se implementó como una solución al desempleo de mano de obra en el campo mexicano, sin embargo, actualmente las zonas rurales del país enfrentan el mismo problema. Con la finalidad de determinar el impacto del TLCAN sobre el empleo de mano de obra en el sector agrícola de México, se calcularon sus fuentes de crecimiento de 1994 a 2010. Los resultados indican que de 1994 a 2010 el cambio en la estructura productiva fue desfavorable al empleo, no obstante, el empleo agrícola na...

  1. Elementos de diseño de maquinaria agrícola: informe de año sabático

    OpenAIRE

    2007-01-01

    El texto que aquí se presenta se adapta al programa de la asignatura Mecanismos que actualmente viene impartiéndose en la formación de los Ingenieros Agrícolas y servirá de guía al estudio de las máquinas agrícolas para profesiones afines al sector agropecuario. Los estudiantes deberán haber adquirido un conjunto de herramientas de ingeniería que consisten esencialmente de matemáticas, geometría, física y varias de las ciencias básicas como la resistencia de los materiales. Estas herramientas...

  2. Antropometria aplicada aos operadores de tratores agrícolas Anthropometrics applied to the agricultural tractors operators

    Directory of Open Access Journals (Sweden)

    José Fernando Schlosser

    2002-12-01

    Full Text Available O objetivo deste trabalho foi determinar o padrão antropométrico dos operadores de tratores agrícolas da Depressão Central do Rio Grande do Sul. Os operadores de tratores agrícolas foram medidos por meio de um painel constituído por duas chapas metálicas, permanecendo durante as medições em pé, eretos, com o mínimo de roupa possível e em contato com o painel. As variáveis medidas foram as seguintes: altura do corpo; altura ao nível dos olhos; altura ao nível dos olhos sentado; altura do cotovelo; alcance do braço; alcance da mão; distância pé-patela; apoio do assento. Os dados obtidos demonstram que há diferenças entre o biótipo do operador utilizado pela indústria de tratores agrícolas e o do operador da região, de forma que este último apresentou, para todas as medidas, à exceção do apoio do assento, uma média maior. Observa-se também que, para cada medida, os limites inferior e superior do intervalo onde se encontram 90% dos operadores avaliados foram, respectivamente, menores e maiores que o padrão utilizado pela indústria, caracterizando uma maior variação. Levando-se em consideração as diferenças existentes entre o perfil antropométrico dos operadores de tratores agrícolas da Depressão Central do Rio Grande do Sul e os parâmetros utilizados pela indústria, pode-se confirmar a hipótese de que os tratores agrícolas que se encontram atualmente em comercialização no Brasil podem não oferecer o conforto necessário ao operador desta região .The objective of this work was to evaluate the anthropometric measures of the agricultural tractor operators of the Central Region of Rio Grande do Sul State. The agricultural tractor operators were measured through a panel that was made of two metallic plates. During the measurement, they were standing, wearing the minimum amount clothes possible, and touching the panel. The measures body height, eyes level height (standing, eyes level height (sitting, elbow

  3. State, Bank and Agricultural Credit in Sinaloa and Sonora: The Banco de Sinaloa and Banco Agrícola Sonorense, 1933-1976 Estado, banca y crédito agrícola en Sinaloa y Sonora: El Banco de Sinaloa y el Banco Agrícola Sonorense, 1933-1976

    Directory of Open Access Journals (Sweden)

    Gustavo Aguilar Aguilar

    2011-01-01

    Full Text Available In the Northwest of México the increase in the agricultural productivity in the years between 1940 and 1970, was due to the expansion of the farming lands, the use of improved seeds and fertilizer, mechanization, the greater availability of credit, the irrigation system and road improvement. The important intervention from the Mexican state to implement policies of investment with the support of internationally development agencies, and grant credit facilities for the development of agriculture trough the creation of official agricultural banks and the facilities to the constitution of private commercial banks. After the disarticulation of the bank in México due to the revolution, is advanced with steady steps in restructuring the banking system with the creation of a new banking law, the foundation of Banco de México and the Comision Nacional Bancaria in 1924; Banco Nacional de Credito Agricola (1926, the Banco Nacional de Credito Ejidal (1935, Banco Nacional de Comercio Exterior (1937 and the Banco Nacional Agropecuario (1965, which gave financial support to small farmers and ejidatarios (members of a cooperative. The main farmers of Sinaloa and Sonora in collaboration with the federal government through the Comision Monetaria and the Banco de México founded the Banco de Sinaloa and Banco Agricola Sonorense in 1933. Explain the impact these financial institutions had in the agricultural credit of Sinaloa and Sonora will be the central objective of this work.En el Noroeste de México el incremento en la productividad agrícola entre los años de 1940 y 1970, fue debido a la expansión de las tierras de cultivo, el uso de fertilizantes y semillas mejoradas, la mecanización, la mayor disponibilidad de créditos, a los sistemas de irrigación y el mejoramiento de las carreteras. Así como la importante intervención del Estado mexicano al implementar políticas de inversión con el apoyo de agencias internacionales de desarrollo, y otorgar

  4. HTR-2014 Paper Comparison of fission product release predictions using PARFUME with results from the AGR-1 irradiation experiment

    Energy Technology Data Exchange (ETDEWEB)

    Blaise Collin

    2001-10-01

    The PARFUME (PARticle FUel ModEl) code was used to predict fission product release from tristructural isotropic (TRISO) coated fuel particles and compacts during the first irradiation experiment (AGR-1) of the Advanced Gas Reactor Fuel Development and Qualification program. The PARFUME model for the AGR-1 experiment used the fuel compact volume average temperature for each of the 620 days of irradiation to calculate the release of fission products silver, cesium, and strontium from a representative particle for a select number of AGR-1 compacts. Post-irradiation examination (PIE) measurements provided data on release of fission products from fuel compacts and fuel particles, and retention of fission products in the compacts outside of the SiC layer. PARFUME-predicted fractional release of these fission products was determined and compared to the PIE measurements. Results show an overall over-prediction of the fractional release of cesium by PARFUME. For particles with failed silicon carbide (SiC) layers, the over-prediction is by a factor of about two, corresponding to an over-estimation of the diffusivity in uranium oxycarbide (UCO) by a factor of about 100. For intact particles, whose release is much lower, the over-prediction is by an average of about an order of magnitude, which could additionally be attributed to an over-estimated diffusivity in SiC by about 30%. The release of strontium from intact particles is also over-estimated by PARFUME, which also points towards an over-estimated diffusivity of strontium in either SiC or UCO, or possibly both. The measured strontium fractional release from intact particles varied considerably from compact to compact, making it difficult to assess the effective over-estimation of the diffusivities. Furthermore, the release of strontium from particles with failed SiC is difficult to observe experimentally due to the release from intact particles, preventing any conclusions to be made on the accuracy or validity of the

  5. First elevated-temperature performance testing of coated particle fuel compacts from the AGR-1 irradiation experiment

    Energy Technology Data Exchange (ETDEWEB)

    Charles A. Baldwin; John D. Hunn; Robert N. Morris; Fred C. Montgomery; Chinthaka M. Silva; Paul A. Demkowicz

    2014-05-01

    In the AGR-1 irradiation experiment, 72 coated-particle fuel compacts were taken to a peak burnup of 19.5% fissions per initial metal atom with no in-pile failures. This paper discusses the first post-irradiation test of these mixed uranium oxide/uranium carbide fuel compacts at elevated temperature to examine the fuel performance under a simulated depressurized conduction cooldown event. A compact was heated for 400 h at 1600 degrees C. Release of 85Kr was monitored throughout the furnace test as an indicator of coating failure, while other fission product releases from the compact were periodically measured by capturing them on exchangeable, water-cooled deposition cups. No coating failure was detected during the furnace test, and this result was verified by subsequent electrolytic deconsolidation and acid leaching of the compact, which showed that all SiC layers were still intact. However, the deposition cups recovered significant quantities of silver, europium, and strontium. Based on comparison of calculated compact inventories at the end of irradiation versus analysis of these fission products released to the deposition cups and furnace internals, the minimum estimated fractional losses from the compact during the furnace test were 1.9 x 10-2 for silver, 1.4 x 10-3 for europium, and 1.1 x 10-5 for strontium. Other post-irradiation examination of AGR-1 compacts indicates that similar fractions of europium and silver may have already been released by the intact coated particles during irradiation, and it is therefore likely that the detected fission products released from the compact in this 1600 degrees C furnace test were from residual fission products in the matrix. Gamma analysis of coated particles deconsolidated from the compact after the heating test revealed that silver content within each particle varied considerably; a result that is probably not related to the furnace test, because it has also been observed in other as-irradiated AGR-1 compacts. X

  6. First elevated-temperature performance testing of coated particle fuel compacts from the AGR-1 irradiation experiment

    Energy Technology Data Exchange (ETDEWEB)

    Baldwin, Charles A., E-mail: baldwinca@ornl.gov [Oak Ridge National Laboratory (ORNL), P.O. Box 2008, Oak Ridge, TN 37831-6295 (United States); Hunn, John D.; Morris, Robert N.; Montgomery, Fred C.; Silva, Chinthaka M. [Oak Ridge National Laboratory (ORNL), P.O. Box 2008, Oak Ridge, TN 37831-6295 (United States); Demkowicz, Paul A. [Idaho National Laboratory (INL), P.O. Box 1625, Idaho Falls, ID 83414 (United States)

    2014-05-01

    In the AGR-1 irradiation experiment, 72 coated-particle fuel compacts were taken to a peak burnup of 19.5% fissions per initial metal atom with no in-pile failures. This paper discusses the first post-irradiation test of these mixed uranium oxide/uranium carbide fuel compacts at elevated temperature to examine the fuel performance under a simulated depressurized conduction cooldown event. A compact was heated for 400 h at 1600 °C. Release of {sup 85}Kr was monitored throughout the furnace test as an indicator of coating failure, while other fission product releases from the compact were periodically measured by capturing them on exchangeable, water-cooled deposition cups. No coating failure was detected during the furnace test, and this result was verified by subsequent electrolytic deconsolidation and acid leaching of the compact, which showed that all SiC layers were still intact. However, the deposition cups recovered significant quantities of silver, europium, and strontium. Based on comparison of calculated compact inventories at the end of irradiation versus analysis of these fission products released to the deposition cups and furnace internals, the minimum estimated fractional losses from the compact during the furnace test were 1.9 × 10{sup −2} for silver, 1.4 × 10{sup −3} for europium, and 1.1 × 10{sup −5} for strontium. Other post-irradiation examination of AGR-1 compacts indicates that similar fractions of europium and silver may have already been released by the intact coated particles during irradiation, and it is therefore likely that the detected fission products released from the compact in this 1600 °C furnace test were from residual fission products in the matrix. Gamma analysis of coated particles deconsolidated from the compact after the heating test revealed that silver content within each particle varied considerably; a result that is probably not related to the furnace test, because it has also been observed in other as

  7. Treball pràctic d'edafologia i química agrícola. Curs 2005-2006

    OpenAIRE

    Universitat de Barcelona. Facultat de Farmàcia

    2005-01-01

    Pla docent de l'assignatura Treball pràctic d'edafologia i química agrícola de l'Ensenyament de Ciència i Tecnologia dels Aliments. Curs acadèmic 2005-2006. Departament de Productes Naturals, Biologia Vegetal i Edafologia.

  8. Structure of the Staphylococcus aureus AgrA LytTR Domain Bound to DNA Reveals a Beta Fold with an Unusual Mode of Binding

    Energy Technology Data Exchange (ETDEWEB)

    Sidote,D.; Barbieri, C.; Wu, T.; Stock, A.

    2008-01-01

    The LytTR domain is a DNA-binding motif found within the AlgR/AgrA/LytR family of transcription factors that regulate virulence factor and toxin gene expression in pathogenic bacteria. This previously uncharacterized domain lacks sequence similarity with proteins of known structure. The crystal structure of the DNA-binding domain of Staphylococcus aureus AgrA complexed with a DNA pentadecamer duplex has been determined at 1.6 Angstroms resolution. The structure establishes a 10-stranded {beta} fold for the LytTR domain and reveals its mode of interaction with DNA. Residues within loop regions of AgrA contact two successive major grooves and the intervening minor groove on one face of the oligonucleotide duplex, inducing a substantial bend in the DNA. Loss of DNA binding upon substitution of key interacting residues in AgrA supports the observed binding mode. This mode of protein-DNA interaction provides a potential target for future antimicrobial drug design.

  9. Structure of the Staphylococcus aureus AgrA LytTR Domain Bound to DNA Reveals a Beta Fold with a Novel Mode of Binding

    Science.gov (United States)

    Sidote, David J.; Barbieri, Christopher M.; Wu, Ti; Stock, Ann M.

    2008-01-01

    SUMMARY The LytTR domain is a DNA-binding motif found within the AlgR/AgrA/LytR family of transcription factors that regulate virulence factor and toxin gene expression in pathogenic bacteria. This previously uncharacterized domain lacks sequence similarity with proteins of known structure. The crystal structure of the DNA-binding domain of Staphylococcus aureus AgrA complexed with a DNA pentadecamer duplex has been determined at 1.6 Å resolution. The structure establishes a 10-stranded β fold for the LytTR domain and reveals a novel mode of interaction with DNA. Residues within loop regions of AgrA contact two successive major grooves and the intervening minor groove on one face of the oligonucleotide duplex, inducing a substantial bend in the DNA. Loss of DNA-binding upon substitution of key interacting residues in AgrA supports the observed binding mode. This novel mode of protein-DNA interacton provides a potential target for future antimicrobial drug design. PMID:18462677

  10. Structure of the Staphylococcus aureus AgrA LytTR domain bound to DNA reveals a beta fold with an unusual mode of binding.

    Science.gov (United States)

    Sidote, David J; Barbieri, Christopher M; Wu, Ti; Stock, Ann M

    2008-05-01

    The LytTR domain is a DNA-binding motif found within the AlgR/AgrA/LytR family of transcription factors that regulate virulence factor and toxin gene expression in pathogenic bacteria. This previously uncharacterized domain lacks sequence similarity with proteins of known structure. The crystal structure of the DNA-binding domain of Staphylococcus aureus AgrA complexed with a DNA pentadecamer duplex has been determined at 1.6 A resolution. The structure establishes a 10-stranded beta fold for the LytTR domain and reveals its mode of interaction with DNA. Residues within loop regions of AgrA contact two successive major grooves and the intervening minor groove on one face of the oligonucleotide duplex, inducing a substantial bend in the DNA. Loss of DNA binding upon substitution of key interacting residues in AgrA supports the observed binding mode. This mode of protein-DNA interaction provides a potential target for future antimicrobial drug design.

  11. Los productos agrícolas Evaluación cualitativa y clasificación. Métodos no destructivos

    OpenAIRE

    Ruiz-Altisent, Margarita; Chen, Pictiaw

    1990-01-01

    Este trabajo presenta una descripción de los diferentes métodos no destructivos utilizables para la tría, la clasificación y la evaluación cualitativa de productos agrícolas, desarrollados por diversos investigadores en las tres últimas décadas.

  12. Treball pràctic d'edafologia i química agrícola. Curs 2008-2009

    OpenAIRE

    Universitat de Barcelona. Facultat de Farmàcia

    2008-01-01

    Pla docent de l'assignatura Treball pràctic d'edafologia i química agrícola de l'Ensenyament de Ciència i Tecnologia dels Aliments. Curs acadèmic 2008-2009. Departament Productes Naturals, Biologia Vegetal i Edafologia.

  13. Eficiência energética de um trator agrícola utilizando duas configurações de tomada de potência

    Directory of Open Access Journals (Sweden)

    Ulisses Giacomini Frantz

    2014-07-01

    Full Text Available A tomada de potência (TDP de um trator agrícola tem por principal finalidade transmitir a potência gerada no motor, para acionamento de órgãos ativos das máquinas agrícolas. Tendo em vista a necessidade de se aumentar a eficiência energética na agricultura, alguns fabricantes disponibilizam para os agricultores uma configuração de TDP que proporciona o acionamento dessas máquinas a um regime de rotação menor do motor do trator. Assim, a rotação da TDP é mantida podendo-se obter uma redução do consumo de combustível. Este trabalho objetivou quantificar o consumo de combustível de um trator agrícola, operando com duas configurações de TDP (normal e econômica em duas áreas agrícolas de relevo distinto. Como resultado, evidencia-se que, com a utilização da TDP econômica, tanto o consumo horário quanto o consumo operacional de combustível, em ambas as áreas trabalhadas, foi menor quando comparado à TDP normal.

  14. Entorno de Aprendizaje Personalizado (PLE) para la asignatura de Investigación de Operaciones en Ingeniería Agrícola

    National Research Council Canada - National Science Library

    Yosleidy Roque Alayón; Alexander Sánchez Díaz; Alexander López Padrón; Astrid Fernández de Castro Fabre; Daniella Moura de Sousa

    2016-01-01

    ... de impartición de la asignatura Investigación de Operaciones (IO) en la carrera Ingeniería Agrícola en la UNAH. La propuesta se basa en el uso de diferentes estrategias de aprendizajes centradas...

  15. Comparative analysis of agr groups and virulence genes among subclinical and clinical mastitis Staphylococcus aureus isolates from sheep flocks of the Northeast of Brazil.

    Science.gov (United States)

    de Almeida, Lara M; de Almeida, Mayra Zilta P R B; de Mendonça, Carla L; Mamizuka, Elsa M

    2013-01-01

    Staphylococcus aureus is one of the most frequent mastitis causative agents in small ruminants. The expression of most virulence genes of S. aureus is controlled by an accessory gene regulator (agr) locus. This study aimed to ascertain the prevalence of the different agr groups and to evaluate the occurrence of encoding genes for cytotoxin, adhesins and toxins with superantigen activity in S. aureus isolates from milk of ewes with clinical and subclinical mastitis in sheep flocks raised for meat production The agr groups I and II were identified in both cases of clinical and subclinical mastitis. Neither the arg groups III and IV nor negative agr were found. The presence of cflA gene was identified in 100% of the isolates. The frequency of hla and lukE-D genes was high - 77.3 and 82.8%, respectively and all isolates from clinical mastitis presented these genes. The sec gene, either associated to tst gene or not, was identified only in isolates from subclinical mastitis. None of the following genes were identified: bbp, ebpS, cna, fnbB, icaA, icaD, bap, hlg, lukM-lukF-PV and se-a-b-d-e.

  16. Medida do ângulo horizontal de ataque dos discos de grades agrícolas de dupla ação e aplicação a uma propriedade agrícola

    Directory of Open Access Journals (Sweden)

    Rubismar Stolf

    2010-01-01

    Full Text Available O conhecimento do ângulo de ataque de grades agrícolas é importante, pois o mesmo influencia a exigência em força de tração, a profundidade e a qualidade da gradagem. O objetivo deste trabalho foi desenvolver um método de medida do ângulo horizontal, de ataque, dos discos de grades de dupla ação com as seguintes características: rápido, de fácil medida e preciso, para aplicação no local de trabalho das grades. O princípio do método proposto baseia-se no fato de que é possível circunscrever grades de dupla ação em um trapézio isósceles e no teorema da trigonometria no qual ângulos com lados perpendiculares entre si formam ângulos iguais. Assim, o método desenvolvido pode ser enunciado como segue: "o seno do ângulo de ataque de uma grade de dupla ação é igual à diferença entre a base maior e a base menor dividida por duas vezes o lado do trapézio". Dessa forma, três medidas de comprimento realizadas com uma trena, ou seja, base maior, base menor e o lado do trapézio, permitem determinar o valor do seno e, consequentemente, o próprio ângulo de ataque da grade. Foram levantados os ângulos de ataque de onze grades agrícolas de propriedade da Destilaria Londra, de Itaí, estado de São Paulo, comprovando a rapidez e facilidade de utilização do método.

  17. AGR-3/4 Data Qualification Report for ATR Cycles 151A, 151B, 152A, 152B, 154A, and 154B

    Energy Technology Data Exchange (ETDEWEB)

    Binh T. Pham

    2014-02-01

    This data report provides the qualification status of Advanced Gas Reactor-3/4 (AGR-3/4) fuel irradiation experimental data from Advanced Test Reactor (ATR) Cycles 151A, 151B, 152A, 152B, 154A, and 154B, as recorded in the Nuclear Data Management and Analysis System (NDMAS). Of these cycles, ATR Cycle 152A is a low power cycle that occurred when the ATR core was briefly at low power. The irradiation data are not used for physics and thermal calculation, but the qualification status of these cycle data is still covered in this report. On the other hand, during ATR Cycles 153A (unplanned Outage cycle) and 153B (Power Axial Locator Mechanism [PALM] cycle), the AGR-3/4 was pulled out from the ATR core and stored in the canal to avoid being overheated. Therefore, qualification of the AGR-3/4 irradiation data from these 2 cycles was excluded in this report. By the end of ATR Cycle 154B, AGR-3/4 was irradiated for a total of 264.1 effective full power days. The AGR-3/4 data streams addressed in this report include thermocouple (TC) temperatures, sweep gas data (flow rates, pressure, and moisture content), and Fission Product Monitoring System (FPMS) data (release rates and release-to-birth rate ratios [R/Bs]) for each of the twelve capsules in the AGR-3/4 experiment. The final data qualification status for these data streams is determined by a Data Review Committee (DRC) composed of AGR technical leads, Sitewide Quality Assurance (QA), and NDMAS analysts. The DRC convened on February 12, 2014, reviewed the data acquisition process, and considered whether the data met the requirements for data collection as specified in QA-approved Very High Temperature Reactor (VHTR) Technology Development Office (TDO) data collection plans. The DRC also examined the results of NDMAS data testing and statistical analyses, and confirmed the qualification status of the data as given in this report.

  18. A eficácia organizacional das instituições portuguesas de ensino superior agrário

    OpenAIRE

    Fernandes, António

    2006-01-01

    A avaliação da eficácia organizacional das instituições portuguesas de ensino superior agrário é o tema central desta comunicação. O enquadramento teórico do tema revela a inexistência de consensos relativamente ao conceito estudado. Por essa razão, para fazer a construção teórica acerca da eficácia organizacional foi necessário recorrer ao uso de bases teóricas já existentes que permitissem pôr alguma ordem na confusão existente. Assim, às quatro dimensões de eficácia organizacional que pode...

  19. Sensitivity Evaluation of the Daily Thermal Predictions of the AGR-1 Experiment in the Advanced Test Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Grant Hawkes; James Sterbentz; John Maki

    2011-05-01

    A temperature sensitivity evaluation has been performed for the AGR-1 fuel experiment on an individual capsule. A series of cases were compared to a base case by varying different input parameters into the ABAQUS finite element thermal model. These input parameters were varied by ±10% to show the temperature sensitivity to each parameter. The most sensitive parameters are the outer control gap distance, heat rate in the fuel compacts, and neon gas fraction. Thermal conductivity of the compacts and graphite holder were in the middle of the list for sensitivity. The smallest effects were for the emissivities of the stainless steel, graphite, and thru tubes. Sensitivity calculations were also performed varying with fluence. These calculations showed a general temperature rise with an increase in fluence. This is a result of the thermal conductivity of the fuel compacts and graphite holder decreasing with fluence.

  20. Fuentes de crecimiento del empleo en el sector agrícola del norte de México

    Directory of Open Access Journals (Sweden)

    José Alberto Salazar García

    2001-01-01

    Full Text Available El desempleo de mano de obra es uno de los problemas más agudos que actualmente enfrentan las zonas rurales de México. Con la finalidad de determinar cómo el cambio en la estructura productiva del sector agrícola del norte de México ha afectado el empleo rural de la región, se calculan las fuentes de crecimiento del empleo de mano de obra de 1991 a 1998. Los resultados indican que en Baja California, Chihuahua y Sonora el cambio en la estructura productiva fue positivo al empleo, mientras que en Coahuila, Sinaloa y Tamaulipas fue negativo. A nivel regional el cambio en la estructura productiva fue desfavorable al empleo; sin embargo, de 1991 a 1998 éste creció en 7.5 millones de jornadas a causa de un aumento en la superficie cosechada en 382 mil hectáreas.

  1. La otra Cuba, colonización blanca y diversificación agrícola

    OpenAIRE

    Naranjo Orovio, Consuelo

    2003-01-01

    [ES] Estudio del proyecto político y social de José Antonio Saco, basado en un proyecto económico en el que la organización de la agricultura cubana era el punto central. Éste, alejado de los planteamientos dominantes de la sacarocracia, mantenía una posición antiesclavista y apostó por la introducción de una población campesina blanca, y la diversificación agrícola con cultivos como naranja, añil y arroz, entre otros. Este proyecto reformista suponía una serie de cambios en cuanto al increme...

  2. Agronomía, agrónomos y estado en Brasil: organizaciones y disputas (1930-1961

    Directory of Open Access Journals (Sweden)

    Sonia Regina De Mendonça

    2004-01-01

    Full Text Available This paper objective a compared analysis of the projects for the Brazilian agriculture transmitted by two entities of agronomy professionals in Brazil between 1930 and 1961: the Brazilian Society of Agronomy (SBA and the Society from São Paulo of Agronomy (SPA. The research supported by the newspapers of these entities supply data on the main practical take for each one of them, as well as it allows reconstituting its directing staff instrument capable to give intelligibility to the different projects. Therefore, while the leaders of SBA - simultaneously graduates for the National School of Agronomy, employees of the Ministry of the Agriculture and directors of the National Society of Agriculture - they defended the state incentive to the productive diversification and the standardization of new agricultural products returned to the export, the agronomists from SPA, more directly articulated to the great industrial bourgeoisie from São Paulo, independently of its school origin, they proposed clearly, already in the decade of 1940, the industrialization of the Brazilian agriculture, by means of the propaganda of agricultural industrial input and of the implementation of the industry of tractors in the country.El trabajo estudia, de modo comparado, dos proyectos para la agricultura brasileña, elaborados por dos de las sociedades que representaron a los agrónomos entre 1930 y 1961: la Sociedad Brasileña de Agronomía (SBA y la Sociedad Paulista de Agronomía (SPA. El análisis de los periódicos de estas agremiaciones ofrece información sobre las principales gestiones, reivindicaciones y prácticas emprendidas por cada una de ellas. También brinda elementos para reconstruir la acción de sus cuadros dirigentes, la cual se considera aquí como instrumento y vehículo representativo de los distintos proyectos. Mientras los dirigentes de la SBA - simultáneamente diplomados por la Escuela Nacional de Agronomía, funcionarios del Ministerio de

  3. El cabotaje marítimo en la cadena de suministros agrícola de Puerto Rico

    Directory of Open Access Journals (Sweden)

    William Suárez-Gómez

    2016-07-01

    Full Text Available El presente estudio examina el efecto multidimensional del cabotaje marítimo que regula el transporte marítimo entre los mercados de Estados Unidos de Norteamérica y Puerto Rico. El objetivo del estudio fue analizar los efectos que esta medida no tarifaria tiene sobre el sector agroindustrial en Puerto Rico. La metodología de investigación consistió de entrevistas semiestructuradas y análisis de datos secundarios de los rubros agrícolas de mayor importación. Los resultados obtenidos concluyen que es la interacción de medidas no tarifarias inherentes a la relación comercial entre ambos países que incide en la eficiencia y competitividad del sector agroindustrial en Puerto Rico.

  4. Utilització de l'oli de colza com a biocarburant en explotacions agrícoles

    OpenAIRE

    Esteban Dalmau, Bernat; Baquero Armans, Grau; Puig Vidal, Rita; Riba Ruiz, Jordi-Roger; Rius Carrasco, Antoni

    2010-01-01

    La utilització de l’oli de colza com a carburant és una tecnologia que ja s’utilitza a altres països europeus com Alemanya i Dinamarca, degut principalment a dos factors: el gasoil agrícola està menys subvencionat i el grau de conscienciació mediambiental és major en aquest països. L’oli de colza és un biocarburant que s’obté del premsat de llavors de plantes oleaginoses i que, realitzant una petita modificació al sistema d’alimentació dels motors dièsel, pot ser utilitzat com a comb...

  5. Dinámicas heterogéneas en la industria de maquinaria agrícola argentina

    Directory of Open Access Journals (Sweden)

    Pablo José Lavarello

    2011-01-01

    Full Text Available El objeto de este artículo es el análisis de la dinámica tecnológica y productiva de las industrias de maquinaria agrícola en Argentina. Se plantea como hipótesis que a pesar de que ciertos subsectores de la industria han logrado insertarse como exportadores en segmentos específicos del mercado internacional, la industria presenta un déficit comercial persistente. Los procesos de racionalización de las empresas multinacionales del sector y las respuestas de las empresas locales frente a la difusión de nuevos paquetes agronómicos explican estas dinámicas diferenciadas. En este contexto, surge como interrogante si el actual esquema de políticas industriales horizontales permiten superar la mencionada heterogeneidad.

  6. El cabotaje marítimo en la cadena de suministros agrícola de Puerto Rico

    Directory of Open Access Journals (Sweden)

    William Suárez-Gómez

    2016-01-01

    Full Text Available El presente estudio examina el efecto multidimensional del cabotaje marítimo que regula el transporte marítimo entre los mercados de Estados Unidos de Norteamérica y Puerto Rico. El objetivo del estudio fue analizar los efectos que esta medida no tarifaria tiene sobre el sector agroindustrial en Puerto Rico. La metodología de investigación consistió de entrevistas semiestructuradas y análisis de datos secundarios de los rubros agrícolas de mayor importación. Los resultados obtenidos concluyen que es la interacción de medidas no tarifarias inherentes a la relación comercial entre ambos países que incide en la eficiencia y competitividad del sector agroindustrial en Puerto Rico.

  7. Staphylococcus epidermidis recovered from indwelling catheters exhibit enhanced biofilm dispersal and "self-renewal" through downregulation of agr

    DEFF Research Database (Denmark)

    Dai, Lu; Yang, Liang; Parsons, Chris

    2012-01-01

    Background: In recent years, Staphylococcus epidermidis (Se) has become a major nosocomial pathogen and the most common cause of infections of implanted prostheses and other indwelling devices. This is due in part to avid biofilm formation by Se on device surfaces. However, it still remains unknown...... that how the process of Se biofilm development is associated with relapsed infection in such patients.Results: We have identified clinical Se isolates displaying enhanced biofilm dispersal and self-renewal relative to reference strain. These isolates also exhibit enhanced initial cell attachment......, extracellular DNA release, cell autolysis and thicker microcolonies during biofilm development relative to reference strain. Our genetic analyses suggest that these clinical isolates exhibit significant downregulation of RNAIII, the effector molecule of the agr quorum sensing system, and upregulation...

  8. Levels of alpha-toxin correlate with distinct phenotypic response profiles of blood mononuclear cells and with agr background of community-associated Staphylococcus aureus isolates.

    Science.gov (United States)

    Mairpady Shambat, Srikanth; Haggar, Axana; Vandenesch, Francois; Lina, Gerard; van Wamel, Willem J B; Arakere, Gayathri; Svensson, Mattias; Norrby-Teglund, Anna

    2014-01-01

    Epidemiological studies of Staphylococcus aureus have shown a relation between certain clones and the presence of specific virulence genes, but how this translates into virulence-associated functional responses is not fully elucidated. Here we addressed this issue by analyses of community-acquired S. aureus strains characterized with respect to antibiotic resistance, ST types, agr types, and virulence gene profiles. Supernatants containing exotoxins were prepared from overnight bacterial cultures, and tested in proliferation assays using human peripheral blood mononuclear cells (PBMC). The strains displayed stable phenotypic response profiles, defined by either a proliferative or cytotoxic response. Although, virtually all strains elicited superantigen-mediated proliferative responses, the strains with a cytotoxic profile induced proliferation only in cultures with the most diluted supernatants. This indicated that the superantigen-response was masked by a cytotoxic effect which was also confirmed by flow cytometry analysis. The cytotoxic supernatants contained significantly higher levels of α-toxin than did the proliferative supernatants. Addition of α-toxin to supernatants characterized as proliferative switched the response into cytotoxic profiles. In contrast, no effect of Panton Valentine Leukocidin, δ-toxin or phenol soluble modulin α-3 was noted in the proliferative assay. Furthermore, a significant association between agr type and phenotypic profile was found, where agrII and agrIII strains had predominantly a proliferative profile whereas agrI and IV strains had a predominantly cytotoxic profile. The differential response profiles associated with specific S. aureus strains with varying toxin production could possibly have an impact on disease manifestations, and as such may reflect specific pathotypes.

  9. Metodologías para establecer valores de referencia de metales pesados en suelos agrícolas: perspectivas para Colombia

    Directory of Open Access Journals (Sweden)

    Germán Rueda Saa

    2011-07-01

    Full Text Available Los impactos ambientales de los metales pesados en los suelos están relacionados con su carácter tóxico cuando se acumulan o interactúan con algunas propiedades específicas, se movilizan a través del perfil a la cadena trófica mediante los cuerpos de agua o los cultivos y pueden llegar a afectar la salud humana. En países desarrollados el establecimiento de valores de referencia de estos metales ha permitido el mejoramiento de la planeación y la gestión ambiental del recurso suelo, y se ha convertido en un instrumento de control para las entidades ambientales que ha permitido evaluar el impacto en diferentes actividades agrícolas. En este artículo se analizan diversos conceptos relacionados con los niveles de metales pesados en suelos agrícolas y la incidencia de las características edafológicas en su concentración. Se revisan, igualmente, algunas metodologías para derivar valores de referencia específicos aplicables a suelos agrícolas colombianos, y se plantean algunas perspectivas orientadas a la protección y recuperación de suelos en el país. En Colombia en la actualidad no se cuenta con criterios y estándares de calidad para medir la contaminación por metales pesados en suelos agrícolas; por esto se hace necesario gestionar el apoyo de entidades gubernamentales con el fin de iniciar y desarrollar investigaciones en diferentes sectores agrícolas primarios, contribuyendo de esta forma a garantizar una producción más limpia y la sostenibilidad ambiental del recurso suelo.

  10. Metodologías para establecer valores de referencia de metales pesados en suelos agrícolas: Perspectivas para Colombia

    Directory of Open Access Journals (Sweden)

    Rueda Saa Germán

    2011-09-01

    Full Text Available

    Los problemas ambientales de los metales pesados en los suelos están relacionados con su carácter tóxico cuando se acumulan o cuando interactüan con algunas propiedades especificas, se movilizan a  través del perfil a la cadena trófica mediante los cuerpos de agua o los cultivos y pueden llegar a afectar la salud humana. En países desarrollados el establecimiento de valores de referencia de estos metales ha permitido el mejoramiento de la planeación y la gestión ambiental del recurso suelo, y se ha convertido en un instrumento de control para las entidades ambientales que ha permitido evaluar el impacto en diferentes actividades agrícolas.

    En este artículo se analizan diferentes conceptos relacionados con los niveles de metales pesados en suelos agrícolas y la incidencia de las características edafológicas en su concentración. Se revisan, igualmente, algunas metodologias para derivar valores de referencia especificos aplicables a suelos agrícolas colombianos, y se plantean algunas perspectivas orientadas a la protección y recuperación de suelos en el país. En Colombia en la actualidad no se cuenta con criterios y estándares de calidad para metales pesados en suelos agrícolas; por esto se hace necesario gestionar el apoyo de entidades gubernamentales con el fin de iniciar y desarrollar investigaciones en diferentes sectores agricolas primarios, contribuyendo de esta forma a garantizar la producción agrícola y la sostenibilidad ambiental del recurso suelo.

  11. Difference in agr Dysfunction and Reduced Vancomycin Susceptibility between MRSA Bacteremia Involving SCCmec Types IV/IVa and I–III

    Science.gov (United States)

    Choi, Su-Mi; Park, Kyung-Hwa; Shin, Jong-Hee; Choy, Hyon E.; Jung, Sook-In; Kim, Hong Bin

    2012-01-01

    Background Dysfunction of agr, with reduced susceptibility or hetero-resistance to vancomycin, is thought to be associated with a worse outcome of methicillin-resistant Staphylococcus aureus (MRSA) bacteremia (MRSAB). However, the difference in agr dysfunction according to the SCCmec type in MRSA infection is undetermined. We compared the prevalence of agr dysfunction, reduced vancomycin susceptibility and the outcomes of SCCmec IV/IVa and I–III MRSAB. Methods The study included 307 cases of MRSAB. SCCmec types were determined by multiplex PCR. The clinical and microbiological features and outcomes of 58 SCCmec IV/IVa MRSAB were compared with those of 249 SCCmec I–III MRSAB. Results Compared with SCCmec I–III MRSAB, SCCmec IV/IVa MRSAB was associated with lower rates of agr dysfunction (3% vs. 43%), vancomycin minimum inhibitory concentration (MIC) = 2 µg/mL (3% vs. 15%), and hetero-resistance to vancomycin (0% vs. 8%) (all PIVa MRSAB were not different from those in patients with SCCmec I–III MRSAB in multivariate analyses (HR 1.168, 95% CI 0.705–1.938; HR 1.025, 95% CI 0.556–1.889). Conclusions SCCmec IV/IVa MRSAB was associated with lower rates of agr dysfunction and hetero-resistance to vancomycin and a lower vancomycin MIC, compared with SCCmec I–III MRSAB. However, the outcomes of SCCmec IV/IVa MRSAB did not differ from those of SCCmec I–III MRSAB. PMID:23152862

  12. Evaluación de residuos agrícolas para la producción del hongo Pleurotus ostreatus

    Directory of Open Access Journals (Sweden)

    María Bernarda Ruilova Cueva

    2014-01-01

    Full Text Available Se caracterizaron los residuos agrícolas de la provincia de Bolívar, Ecuador, desde el punto de vista de su composición físico-química para su empleo en el cultivo del hongo Pleurotus ostreatus. Los residuos agrícolas utilizados fueron: maíz, trigo, cebada, lenteja, bagazo de caña de azúcar y cascarilla de arroz. Se realizaron análisis de: humedad, cenizas, extracto etéreo, proteína, fibra, extracto libre de nitrógeno, fibra detergente neutra, fibra detergente ácida, lignina, celulosa, hemicelulosa y minerales. Los residuos presentaron valores de humedad entre 9,12 y 13,91 %, después de dos meses de almacenamiento. Por su naturaleza leñosa son ricos en fibra, celulosa, lignina y hemicelulosa. El contenido de carbono fluctuó entre 50,12 y 56,55 %, y es la fuente directa de energía para su metabolismo. El contenido de nitrógeno fue variable 0,38-1,29 %. Se cultivó el hongo en los sustratos analizados y en la producción obtenida se valoró la eficiencia biológica y proteína. Se obtuvo en la mayoría de los casos una relación directa entre el contenido de nitrógeno con la eficiencia biológica y la proteína en el hongo.

  13. Análisis conceptual del uso agrícola del suelo: Su incidencia en la sostenibilidad

    Directory of Open Access Journals (Sweden)

    Maldané Cuello Espinosa

    2013-05-01

    Full Text Available El tema del desarrollo sostenible ha sido muy discutido y analizado en las últimas décadas; no obstante, aún no se ha desarrollado satisfactoriamente; se inició en el año de 1987 con el informe Brundtland denominado Nuestro futuro común, de la Comisión Mundial para el Medio Ambiente. En el informe se puntualiza y se define concretamente al desarrollo sostenible como: “Satisfacer las necesidades del presente sin comprometer la capacidad de satisfacer las futuras generaciones”. En la actualidad, casi todas las personas coinciden con tan importante definición; sin embargo, no se ha plasmado a los niveles que se requiere para deshacer los trances que se exhiben en ese sentido a escala mundial, fruto de los ambiciosos intereses particulares.  El suelo es uno de los recursos que, en condiciones ambientalmente normales, bien puede llenar las expectativas de poder llevar a la praxis tan anhelada descripción, integrando con perspectiva de sistema agrícola los tres elementos claves que la componen: el elemento social, el económico y el ambiental.  El desarrollo de los sistemas agrícolas y sus aplicaciones e implicaciones en el proceso de la sostenibilidad, trae consigo cambios considerables en términos social, económico y ambiental, que, indudablemente, contribuye a tan anhelado proceso, en el sentido de poder lograr un cambio en el entorno común, alcanzando a armonizar la naturaleza, los beneficios económicos y las necesidades de la población.

  14. Funciones agua rendimiento para 14 cultivos agrícolas en condiciones del sur de La Habana

    Directory of Open Access Journals (Sweden)

    Felicita González Robaina

    2013-01-01

    Full Text Available El estudio de las funciones agua rendimiento y su uso dentro de la planificación del uso del agua es una vía importante para trazar estrategias de manejo que contribuyan al incremento en la producción agrícola. Utilizando los datos de consumo de agua, agua aplicada por riego, precipitaciones y los rendimientos obtenidos en más de 100 experimentos de campo realizados fundamentalmente en suelo Ferralítico Rojo de la zona sur de La Habana y con ayuda de herramientas de análisis de regresión en este trabajo se estiman las funciones rendimientos versus agua aplicada para 14 cultivos agrícolas. Respuestas de tipo lineal fueron encontradas para los cultivos de frijol, sorgo, ajo, cebolla, boniato, malanga y piña al relacionar el rendimiento con el agua aplicada por riego. Para los cultivos soya, pimiento, tomate, papa, plátano y banano esta relación se explica mejor a través de funciones cuadráticas. Para el caso particular del maíz, se propone la función por partes con un punto de ruptura alrededor de los 185 mm como mejor opción para explicar la respuesta al riego. Las funciones obtenidas pueden servir como herramientas para alcanzar los rendimientos potenciales de los cultivos estudiados y en la toma de decisiones cuando el recurso agua está limitado.

  15. Cooperativa-escola nas Escolas Técnicas Agrícolas Cooperative-school at the Agricultural Technical Schools

    Directory of Open Access Journals (Sweden)

    P.V. Marques

    1993-12-01

    Full Text Available A dificuldade de gerenciar recursos e proporcionar melhores condições de ensino para os estudantes são algumas das deficiência das Escolas Técnicas Agrícolas (ETAs brasileiras, problemas parcialmente superados por algumas escolas que adotaram a chamada Cooperativa-Escola. Neste trabalho, procura-se discutir alguns aspectos filosóficos referentes às ETAs e como a Cooperativa-Escola pode ajudar a solucionar seus principais problemas educativos e administrativos; um estudo de caso utilizando-se a técnica de auditoria administrativa foi desenvolvido numa ETA cuja Cooperativa-Escola é considerada um modelo de bom funcionamento e alguns procedimentos foram descritos, objetivando-se estender a prática de Cooperativa-Escola para outras escolas técnicas agrícolas brasileiras.Some of the problems with the Brazilian public Agricultural Technical School systems (ETAs are related to resource management and the need to improve teaching and learning conditions. Those deficiencies were partially corrected after setting up Cooperative-Schools that allow the ETAs to raise and to administrate funds. Administrative procedures of the ETAs and how the Cooperative-School could help solving their main educational and adminsitrative problems are discussed in this research. A case study using the management audit technique was developed in one ETA with a well known Cooperative-School. Some observed procedures are described with the intention of extending the practice of Cooperative-Schools to other Brazilian Agricultural Technical Schools.

  16. Detecção de áreas agrícolas em tempo quase real com imagens Modis

    Directory of Open Access Journals (Sweden)

    Isaque Daniel Rocha Eberhardt

    2015-07-01

    Full Text Available Resumo: O objetivo deste trabalho foi desenvolver um método para identificação e monitoramento, em tempo quase real, de áreas agrícolas cultivadas com lavouras temporárias de verão, com uso de imagens orbitais Modis, no Estado do Rio Grande do Sul. A metodologia foi denominada detecção de áreas agrícolas em tempo quase real (DATQuaR e utiliza imagens do sensor Modis referentes aos índices de vegetação (IVs EVI e NDVI, disponibilizadas em composições de 16 dias. Foram utilizadas quatro métricas para agregar os valores de IVs por pixel, dentro dos períodos bimensais avaliados: média, máximo, mínimo e mediana. Para gerar as imagens (ImDATQuaR, a imagem agregada para o período imediatamente anterior foi subtraída da imagem agregada para o período em monitoramento. Essas imagens foram classificadas por meio de fatiamento e comparadas às classes de referência obtidas pela interpretação visual de pixels aleatorizados em imagens Landsat. Cada ImDATQuaR gerou dois mapas DATQuaR: um com filtragem de moda com janela 3x3 pixels e outro sem filtragem. O melhor mapa DATQuaR é produzido com uso de imagens EVI e filtragem - ao se subtrair a imagem de mínimo valor para o período anterior da imagem de máximo valor para o período monitorado - e atinge concordâncias com a referência superiores a 81%.

  17. Influencia de cuatro distancias de trasplante sobre el rendimiento agrícola del cultivar de arroz Amistad-82.

    Directory of Open Access Journals (Sweden)

    Alexander Calero Hurtado

    2012-04-01

    Full Text Available El trabajo consistió en comparar cuatro distancias de trasplante sobre el rendimiento agrícola del cultivar de arroz Amistad-82, durante la siembra de primavera de 2012, el trasplante se realizó de forma manual, sobre un suelo pardo sialítico carbonatado en la finca “La Rosita” perteneciente a la CCS “Heriberto Orellane”, en la provincia de Sancti Spíritus, se utilizó un diseño de bloques al azar, se tomaron posturas jóvenes de 18 días de germinadas, cuatro distancias de plantación 10x15, 15x15, 20x15 y 20x20 cm y una postura por sitio. Se evaluaron los indicadores productivos como el número de tallos, panículas por metro cuadrado, longitud de la panícula, granos por panículas, granos llenos y vanos por panículas, peso de 1000 granos, el rendimiento, así como las ganancias y los costos de producción. Los mejores resultados sobre el rendimiento agrícola del cultivar de arroz Amistad-82 lo alcanzaron las distancias de trasplante 10x15 y 20x15 cm, porque lograron rendimientos superiores a las distancias 15x15 y 20x20 cm, mayor cantidad de granos por panículas y mayores porcentajes de granos llenos por panículas y superaron también el peso en 1000 granos y las ganancias.

  18. El uso de buenas prácticas agrícolas ¿Un problema de economías de escala? Estudio de caso de los productores de la Subcuenca III, Nicaragua

    OpenAIRE

    Alder Miguel Contreras Hernández

    2015-01-01

    Los riesgos del cambio climático y las debilidades productivas que presentan los pequeños y medianos productores suponen un enorme reto en la agenda de crecimiento y desarrollo del sector agrícola nicaragüense. En este sentido, la incorporación de buenas prácticas agrícolas (GAP) a los sistemas de producción vigentes supone una posible estrategia de desarrollo para los grupos de productores más vulnerables, pues permite el acceso a mercados agrícolas más dinámicos y estables y la mejora de lo...

  19. Caracterización parcial de los contratistas de servicios de maquinaria agrícola en la micro región 2 –provincia de La Pampa, Argentina

    OpenAIRE

    Stadler, Soledad; Botta, Guido Fernando

    2015-01-01

    La introducción de nuevas tecnologías como la siembra directa y las semillas transgénicas, han ocasionado notables cambios en los aspectos productivos, económicos, sociales y ambientales. En este contexto, la figura del contratista de servicios de maquinaria agrícola, aumentó notablemente su participación en las actividades agrícolas, no solo en la región pampeana, sino también en las regiones extrapampeanas como consecuencia del corrimiento de la frontera agrícola. En la provincia de La Pamp...

  20. Diseño de un plan de negocios para la creación de una Cooperativa Agrícola de Producción de Granadilla tipo exportación - Grancoop

    OpenAIRE

    2012-01-01

    Grancoop nace de la idea de crear una Cooperativa Agrícola de producción de Granadilla tipo exportación, con el objetivo de asociar a los productores de granadilla, brindándoles educación agrícola profesional en la pre y pos cosecha de la fruta, que impacte en lograr modelos más eficientes y sostenibles en términos ambientales y económicos, aplicando la Norma Técnica Colombiana 5400 de Buenas Prácticas Agrícolas para producir a gran escala y trascender a mercados extranjeros como Europa en do...

  1. Necesidades educacionales sobre riesgo de plaguicidas en el contexto socio-ambiental de las comunidades agrícolas de Sonora

    Directory of Open Access Journals (Sweden)

    M.I. Silveira Gramont

    2016-01-01

    Full Text Available Para proponer estrategias de educación y comunicación sobre plaguicidas en las comunidades agrícolas de Sonora, se requiere situar la problemática de la exposición a plaguicidas en el contexto socio-cultural y ambiental de las comunidades afectadas, tomando en cuenta los factores que contribuyen al mayor riesgo de exposición de los trabajadores agrícolas y de sus familias. Este estudio examina los factores poblacionales, educacionales, culturales y de trabajo de habitantes y trabajadores agrícolas de dichas comunidades, así como las limitaciones de infraestructura comunitaria y de condiciones de vivienda en relación al riesgo de contaminación por plaguicidas. Sobre la base de este análisis se proponen posibles alternativas educacionales orientadas a mitigar tal riesgo en el contexto socio-cultural de dichas comunidades. Método De los estudios reportados sobre la presencia de residuos de plaguicidas en productos agrícolas y acuícolas, en suelos, agua, medio ambiente y en líquidos corporales de niños y adultos de Sonora, se puede concluir que tanto los trabajadores agrícolas como la población que reside cerca de las zonas agrícolas, están sujetos a un mayor riesgo de contaminación por plaguicidas. Para la realización del presente estudio se seleccionaron cinco comunidades localizadas en los valles agrícolas más productivos de Sonora, en las cuales se han llevado a cabo investigaciones relacionadas con plaguicidas. Básicamente, se analizó la información obtenida de encuestas aplicadas a residentes y trabajadores agrícolas de dichas comunidades, para explorar su conocimiento sobre uso y manejo de plaguicidas, percepción del riesgo que tales sustancias representan y las prácticas de protección personal que llevan a cabo para la prevención de dichos riesgos (en el hogar y trabajo. También se describe la infraestructura de los poblados y las viviendas de sus habitantes en relación al potencial de riesgo de contaminaci

  2. Histórico e os limites da reforma agrária na contemporaneidade brasileira History and limits of the agrarian reform in the Brazilian contemporary time

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    Paulo Nakatani

    2012-06-01

    Full Text Available Objetiva-se reconstituir a trajetória da questão fundiária (e agrária na experiência de maior concentração de riqueza e recursos vivenciada no âmbito do sistema capitalista, partindo-se da premissa de que a crescente desigualdade do modelo brasileiro passa necessariamente pela questão agrária. Num segundo momento, procede-se à análise dos limites atualmente colocados a qualquer possibilidade de uma Reforma Agrária ampla e estrutural, dados pelo avanço do agronegócio nos últimos dez anos, pela desmobilização política de parcela significativa da sociedade no que se refere a esta questão e pelos próprios limites estruturais da economia brasileira nos quadros da globalização financeira. O texto será dividido em seis sessões: a colonização e origens do latifúndio; b O modelo agroexportador e a ruptura incompleta; c a questão agrária e a industrialização brasileira; d a questão agrária e o agronegócio; e os limites da reforma agrária na contemporaneidade; f considerações finais.This paper aims at reconstructing the history of the land (agrarian issue considering the greatest concentration of wealth and resources in the capitalist system. The standpoint is that the growing inequality of the Brazilian model is related to the agrarian issue. Secondly, we analyze the limits ­currently placed on any possibility of a comprehensive and structural agrarian reform, due to the advancement of the agribusiness over the last ten years, the political demobilization of a significant portion of society that put this issue aside, and the limits of the Brazilian economy in the context of the financial globalization. The paper is divided into six parts: a colonization and origins of the large landed estates; b the agro-export model and the incomplete rupture; c the agrarian issue and the Brazilian industrialization; d the agrarian issue and the agribusiness; e the limits of the agrarian reform in the contemporary time; f final

  3. Evaluación de riesgo del tratamiento de semillas con plaguicidas para las aves silvestres de ecosistemas agrícolas:el caso de la perdíz roja

    OpenAIRE

    López Antia, Ana

    2015-01-01

    La conservación de las aves agrícolas es uno de los mayores retos de conservación en Europa. El declive de estas aves está claramente ligado a la transformación del sistema de producción agrícola que se viene dando desde mediados del pasado siglo. Uno de los puntos de partida de esta tesis es que la intensificación agrícola ha llevado a una reducción en el alimento natural disponible para las aves agrícolas, viéndose éstas obligadas a buscar fuentes alternativas de alimento como la semilla de...

  4. The discovery by Gh. Benga of the first water channel protein in 1985 in Cluj-Napoca, Romania, A few years before P. Agre (2003 Nobel Prize in Chemistry).

    Science.gov (United States)

    Cucuianu, M

    2006-01-01

    The first water channel protein, now called aquaporin 1, was identified or "seen" in situ in the human red blood cell membrane by Benga's group in 1985. It was again "seen" when it was by chance purified by Agre'group in 1988 and was again identified when its main feature, the water transport property, was found by Agre's group in 1992. Consequently, the omission of Gh. Benga from the 2003 Nobel Prize in Chemistry (half of which was awarded to P. Agre "for the discovery of the water channels") is a new mistake in the award of Nobel Prizes. The growing recognition of the priority of Gh. Benga over P. Agre in the discovery of water channels is documented in this paper.

  5. The agr inhibitors solonamide B and analogues alter immune responses to Staphylococccus aureus but do not exhibit adverse effects on immune cell functions

    DEFF Research Database (Denmark)

    Baldry, Mara; Kitir, Betül; Frøkiær, Hanne;

    2016-01-01

    Staphylococcus aureus infections are becoming increasingly difficult to treat due to antibiotic resistance with the community-associated methicillin-resistant S. aureus (CA-MRSA) strains such as USA300 being of particular concern. The inhibition of bacterial virulence has been proposed as an alte......Staphylococcus aureus infections are becoming increasingly difficult to treat due to antibiotic resistance with the community-associated methicillin-resistant S. aureus (CA-MRSA) strains such as USA300 being of particular concern. The inhibition of bacterial virulence has been proposed...... as an alternative approach to treat multi-drug resistant pathogens. One interesting anti-virulence target is the agr quorum-sensing system, which regulates virulence of CA-MRSA in response to agr-encoded autoinducing peptides. Agr regulation confines exotoxin production to the stationary growth phase...... an agr-negative state may have adverse interactions with host factors in favor of host colonization....

  6. Transmissões presentes em tratores agrícolas no Brasil Transmissions present in agricultural tractors in Brazil

    Directory of Open Access Journals (Sweden)

    Rodrigo Lampert Ribas

    2010-10-01

    Full Text Available O sistema de transmissão de um trator agrícola tem por principal finalidade transmitir a potência gerada no motor ao sistema hidráulico, à tomada de potência e às rodas motrizes. A caixa de câmbio é formada por uma série de engrenagens que permitem a correta seleção da velocidade e do torque mais adequados a uma determinada operação. Assim, as transmissões podem ser classificadas, basicamente, em três categorias: mecânicas, hidrostáticas e hidrodinâmicas, sendo as transmissões mecânicas subdivididas em engrenagens deslizantes e sincronizadas. Este trabalho objetivou analisar os diferentes tipos de transmissões disponibilizados em 169 modelos de tratores fabricados no Brasil, com a finalidade de avaliar a real distribuição nas diferentes faixas de potência e estabelecer possíveis relações entre esses parâmetros. Como resultado, evidencia-se uma forte tendência de tratores agrícolas com potência menor que 111,8kW possuírem transmissão do tipo mecânica, e tratores acima de 111,8kW, do tipo hidrostática.The transmission system of an agricultural tractor has a main purpose to transmit the power generated in the hydraulic motor, the power take off and the drive wheels. The gearshift consists of a series of gears that allows the correct selection of speed and torque more appropriate to a particular operation. Then, the transmissions can be classified, basically, in three categories: mechanical, hydrostatic and hydrodynamic, being the mechanical transmissions subdivided in sliding gear and synchronized. Then, the objective of this research was to analyze the different types of transmissions available in 169 models of tractors made in Brazil in order to evaluate the real distribution of them in different power ranges and establish possible correlations. As a result, it was shown a strong tendency for agricultural tractors with power less than 111.8kW possessing mechanical transmission and tractors above 111.8k

  7. O Comportamento do Preço da Terra Agrícola: um modelo de painel de dados espaciais

    Directory of Open Access Journals (Sweden)

    Regina Lúcia Sanches Malassise

    2015-12-01

    Full Text Available Resumo: O presente artigo analisou o comportamento do preço da terra agrícola nos municípios do Paraná no período de 1999-2011. Partindo da revisão bibliográfica dos principais estudos nacionais sobre o tema, foi possível identificar os determinantes do preço da terra e os métodos utilizados. Neste sentido, optou­-se por estimar um modelo para o preço da terra via painel de dados espaciais. As estimativas indicaram que o valor bruto da produção agropecuária, a valorização patrimonial, o financiamento total à agropecuária, a relação investimento-receita municipal, o percentual da área plantada do município com soja e a incorporação da dependência espacial do preço da terra são variáveis que explicam o preço da terra no estado do Paraná. Estas explicariam 84% dos preços e indicaram que há maior ajuste intrapainel, sendo os efeitos espaciais mais intensos no próprio município e em relação ao todo. Em especial, o modelo proposto avançou em termos estruturais, com a incorporação de variáveis coletadas para todos os 399 municípios do Paraná, e em termos metodológicos, ao estimar via painéis de dados a influência dos efeitos de espacialidade sobre o preço da terra agrícola, destacando a importância da localização e da vizinhança na determinação de tal preço.

  8. Tratamiento térmico con láser de cuchillas de acero para uso agrícola

    Directory of Open Access Journals (Sweden)

    Muñiz, G.

    2003-12-01

    Full Text Available The present paper focuses on the laser surface treatment of mild steels with different %wt of carbon to be used as cutting blades in agricultural applications. The results are discussed in function of the metallographic study, hardness profiles, wear resistance and corrosion testing. Special attention is paid to the results of the results obtained with the experimental steel with carbon 0.33 %wt because it is a new promising material specifically developed to be applied in such agricultural uses. Metallographic studies showed three well defined regions: the laser treated zone, where solid state phase transformation occurs, the heat affected zone (HAZ with partial transformations and finally the bulk metal with the original microstructure. Surface hardness was in all cases higher than the base steel in a depth range 600 μm. Wear resistance is notably improved with laser heat treatment while no detrimental effects were induced in their specific corrosion resistance.

    En el presente trabajo se muestran los resultados obtenidos en el temple superficial mediante láser, sobre aceros con distintos contenidos en carbono susceptibles de empleo en la producción de cuchillas de corte para aplicaciones agrícolas. Se comparan los resultados de los distintos aceros en función de su estudio metalográfico, perfiles de dureza y ensayos de resistencia al desgaste y a la corrosión. Destacan los resultados obtenidos con el acero de 0,33 % de carbono, por tratarse de un acero experimental de producción reciente para su empleo en cuchillas de uso agrícola. Tras el estudio metalográfico, se aprecia, en la capa superficial del metal tratado, la existencia de tres zonas bien definidas: la zona tratada en la que ocurren las transformaciones de fase típicas del temple, una zona de transición, que podemos considerar como la zona afectada térmicamente (ZAT, con transformaciones parciales y, por último, el metal base con su microestructura de origen. Las

  9. Caracterização e dinâmica da modernização agrícola no Paraná em 1995 e 2006

    OpenAIRE

    Edson Ramos de Medeiros

    2014-01-01

    O objetivo da pesquisa é analisar o grau de intensidade da modernização do setor agrícola do Paraná para os anos censitários de 1995 e 2006. A fonte de dados utilizada foi o Censo Agropecuário do Brasil/Instituto Brasileiro de Geografia e Estatística (IBGE) para os anos de 1995 e 2006. Foram utilizados dois métodos para o tratamento e análise de dados: análise fatorial e análise espacial e dados. A Análise Fatorial permitiu construir o Índice de Modernização Agrícola (IMA), e posteriormente a...

  10. Los trabajadores agrícolas mexicanos en los campos de California: migración, empleo y formación de clase en una agricultura intensiva

    Directory of Open Access Journals (Sweden)

    Manuel Adrián Hernández Romero

    2015-12-01

    Full Text Available En este artículo se presenta una aproximación antropológica al proceso de formación de clase, motivado por el asentamiento y estabilización de la fuerza de trabajo migrante mexicana empleada en la agricultura de California. A partir de observación directa de las dinámicas productivas de una mercancía ilustrativa, las uvas para mesa, se describen las pautas de participación laboral en un contexto de capitalismo agrícola avanzado para explorar las formas de proletarización vinculadas al uso de mano de obra externa, analizando tanto los factores que propician proletarización como las condiciones que impiden que el empleo agrícola se iguale a otros sectores de la economía.

  11. Análisis económico de la “bio-carbonización” como práctica de manejo agrícola

    OpenAIRE

    Ramirez, Juan Andres; Rosales Alvarez, Ramon

    2009-01-01

    Las altas concentraciones de gases de efecto invernadero, específicamente CO2, han sido señaladas como la principal causa del cambio climático. La adopción de prácticas agrícolas capaces de incrementar el contenido de carbono en el suelo, ha sido propuesta como una estrategia de bajo costo y disponibilidad inmediata para enfrentar este fenómeno. La Bio-carbonización es una de estas prácticas agrícolas, la cual implica la aplicación de carbón vegetal al suelo, de modo que el carbono queda capt...

  12. Zonificación del Municipio Gibara, útil de trabajo para el comienzo de las actividades extensión agrícola.

    OpenAIRE

    Raciel Ojeda Fernández; Severo Aranda Aranda; Daimarelis Rodríguez Leyva

    2003-01-01

    Se expone la zonificación del municipio Gibara fundamentado en un análisis sistémico del medio donde se desarrolla la producción agropecuaria. Para conseguir este resultado se comenzó con la búsqueda de informaciones del medio físico, socioeconómico y agrícola del municipio. Posteriormente se confeccionaron mapas de hidrología, suelos, temperatura, vías de comunicación terrestres, pluviometría y prácticas agrícolas; a continuación se analizó la información contenida en cada mapa superponiéndo...

  13. Análise da quantidade de azoto em excesso em solos agrícolas na zona vulnerável n.º 1

    OpenAIRE

    Silva, Pedro F. S.; Haie, Naim

    2006-01-01

    O conceito de Zona Vulnerável com vista a proteger as águas contra a poluição difusa causada por nitratos de origem agrícola, foi definido na Directiva 91/676/CEE, publicada no Jornal Oficial das Comunidades de 31 de Dezembro de 1997, a qual foi transposta para a ordem jurídica interna pelo Dec-Lei 235/97 de 3 de Setembro. Os objectivos deste diploma são: a redução da poluição das águas contra a poluição causada por nitratos de origem agrícola, bem como impedir a propagação desta poluição (ar...

  14. Economía de Producción Agrícola en Colombia: Capitulo 1. Regiones Geográficas y Agrícolas de Colombia

    Directory of Open Access Journals (Sweden)

    Beltrán G. Gregorio

    1953-09-01

    y en su parte sur vuelve a ser plana. La cría del ganado parece ser la ocupación principal; se concentra en los alrededores de Villavicencio. Se han hecho varios intentos espontáneos para colonizar parte de esta región pero sin resultados definitivos. Al tratar sobre la agricultura de un país se hace necesario tomar en cuenta la distribución de sus recursos humanos. La población de Colombia es de unos 10 habitantes por kilometro cuadrado, pero esta cifra global no da ni siquiera una idea aproximada de cómo está poblado el país, ya que más del 98 por ciento de su población vive en el tercio occidental de la nación aun dentro de esta zona la fluctuación por departamentos es bastante grande. Por otro lado están las zonas agrícolas pues hemos visto distintas clasificaciones del país en zonas fitogeográficas y de elevación. Sin embargo éstas no tienen un valor económico inmediato. Dentro de ellas existen regiones más pequeñas pero más homogéneas en cuanto al clima, régimen de lluvias, suelos y organización que se especializan en la producción de uno o más agrícolas. Estas regiones deberán servir en el futuro como núcleo de los estudios de economía de producción agrícola, por tener todas ellas sistemas de agricultura más o menos conocidos pero cuya verdadera organización económica se desconoce. Como en el país no se han hecho todavía estudios serios de geografía económica y las publicaciones de la Contraloría General de la República en este campo se han limitado a una recopilación de los pocos datos estadísticos que se disponen los departamentos, se dan las siguientes descripciones de las zonas agrícolas para que se tenga una idea aproximada de sus principales características.

  15. Estratégias de marketing da indústria de tratores agrícolas no Brasil : o caso da Massey-Fergusson e da Valmet

    OpenAIRE

    Bussab, Murilo de Oliveira

    2010-01-01

    Avalia o ambiente de marketing em que os dois maiores fabricantes de tratores agrícolas do país estavam inseridos, entre 1970 e 1996. Levanta o referencial teórico existente a respeito das principais opções estratégicas das empresas. Identifica e avalia as estratégias adotadas pela Massey-Fergusson e pela Valmet

  16. Logística reversa de defensivos agrícolas: fatores que influenciam na consciência ambiental de agricultores gaúchos e mineiros

    Directory of Open Access Journals (Sweden)

    Wagner Junior Ladeira

    2012-03-01

    Full Text Available Nos últimos anos, observa-se um aumento das pressões legais e sociais em favor de uma maior preocupação com o meio ambiente em vários países, incluindo o Brasil. Se antes o foco era indústrias poluidoras, agora, também o setor agrícola sofre essas pressões. Considerando este cenário, o presente estudo tem como objetivo verificar quais são os principais fatores que levam produtores rurais a realizarem a logística reversa de embalagens de defensivos agrícolas. Para isso, foram aplicados questionários a 398 agricultores (residentes no Rio Grande do Sul e em Minas Gerais, produtores de soja, café, fumo, feijão e morango. Analisaram-se tanto as questões ambientais quanto as questões legais incluídas nesse processo. A fim de se atingir o objetivo proposto, foi adotada uma abordagem quantitativa, através da análise de regressão múltipla. No modelo de regressão estimado, observou-se que, dentro do processo de recolhimento de embalagens, três questões foram relacionadas à consciência ambiental: i manuseio de defensivos agrícolas e a legislação atual; ii adoção de tecnologia e de novas práticas e iii riscos a saúde humana. Nos achados empíricos a consciência ambiental recebe fortes interferências de fatores relacionados ao manuseio de defensivos agrícolas e da legislação atual.

  17. Metodologia para estimar o número de dias trabalháveis com máquinas agrícolas

    Directory of Open Access Journals (Sweden)

    Javier Solis Estrada

    2015-08-01

    Full Text Available No atual modelo de agricultura, é indispensável que o produtor conheça a real disponibilidade de tempo para a execução das operações agrícolas ao longo do ciclo das culturas. Este é o primeiro passo para se planejar e se obter maior eficiência na execução dessas operações, que estão sujeitas às variações do clima. As variáveis meteorológicas de uma determinada região influenciam diretamente no número de dias disponíveis para trabalhar com máquinas agrícolas. O objetivo deste trabalho foi estimar as probabilidades de ocorrência de dias favoráveis para o trabalho mecanizado, utilizando-se informações meteorológicas do município de Santa Maria, RS, Brasil. As condições para se considerar o dia como favorável para o trabalho com máquinas foram a precipitação < 5 mm e o armazenamento de água no solo (ARM entre 40 e 90% da capacidade de água disponível (CAD. O método da cadeia de Markov de primeira ordem foi utilizado para estimar as probabilidades condicionais de dias favoráveis ao trabalho com máquinas. Os resultados indicam que a metodologia aplicada para estimar as probabilidades de dias favoráveis ao uso de máquinas agrícolas foi viável, evidenciando as épocas mais apropriadas à execução de operações agrícolas mecanizadas no campo, para o município de Santa Maria, RS.

  18. Relações contratuais de crédito agrícola e o papel dos agentes financeiros privados: teoria e evidências dos EUA

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    Fabio R Chaddad

    2003-01-01

    Full Text Available Este trabalho analisa a questão do financiamento da produção agrícola sob uma ótica sistêmica, considerando o papel dos agentes privados no fornecimento de crédito rural. Desenvolve-se a idéia de que o volume e o custo de recursos financeiros disponibilizados para a produção agrícola são afetados por "fricções" em diversas transações sequenciais interligando emprestadores e tomadores de crédito. O objetivo do trabalho é analisar as vantagens comparativas dos diversos agentes que atuam no mercado de crédito, enfocando o potencial de cada agente em reduzir as tais fricções. Esta análise comparativa baseia-se na leitura do funcionamento do mercado de crédito agrícola dos Estados Unidos e pode ser aplicada nara o desenvolvimento de novos arranjos contratuais no mercado brasileiro.

  19. Formação para o ensino agrícola nos Centros de treinamento de Professores e de auxiliares rurais (1952-1963

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    Iraíde Marques de Freitas Barreiro

    2013-01-01

    Full Text Available Este artículo analiza la enseñanza agrícola propuesta y desarrollada por la Campaña Nacional de Educación Rural (1952-1963 en los Centros de Entrenamientos de Profesores y Auxiliares Rurales. Se analizan los programas de enseñanza de esos cursos publicados en el volumen espacial, número 10, editado por la Campaña en 1961/1962. La enseñanza agrícola componía la educación rural y tenía como objetivo formar profesoras rurales y ampliar conocimientos del hombre del campo para estabilizarlo en su medio. Esa formación buscó suplir la falta de profesores rurales, de conocimientos agrícolas, higiene rural, fuertemente orientada por la “educación de las costumbres”, de como portarse a la mesa y la valoración del ocio racional, así como campañas de registro civil y casamientos, campaña de los árboles, incentivo para elegir representantes de los directorios como forma de educación para la ciudadanía. La ausencia de profesoras rurales y los bajos sueldos denunciados desnudan las prácticas de desvalorización docente de nuestros gobernantes.

  20. Retos del crédito agrícola: estudio de caso de la intermediación financiera en el sur de Sonora, México

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    Mario Alberto Camiro Pérez

    2009-01-01

    Full Text Available En años recientes, la política agrícola oficial ha orientado sus esfuerzos para construir el sistema financiero rural sustentado en un arreglo institucional nuevo. En consecuencia, el Estado mexicano impulsó la creación de la Financiera Rural como banca de desarrollo, y así encaminar sus actividades en torno al crédito agrícola como servicio fundamental del sistema. Asimismo, con el fin de facilitar su transición como banca de segundo piso, se estableció un programa de apoyo a los intermediarios financieros rurales, para mejorar el servicio del crédito agrícola a los productores nacionales. En este contexto, el presente estudio analiza el papel de la Financiera Rural y los retos de la intermediación financiera, con base en un estudio de caso en el valle del Yaqui, Sonora, donde, a pesar de su potencial, las organizaciones de agricultores enfrentan restricciones importantes para acceder a servicios financieros e integrarlos a sus estrategias de desarrollo.

  1. La producción agrícola fronteriza 1977-1981: un análisis estructural

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    Arturo Ranfla González

    1986-01-01

    Full Text Available Este trabajo constituye un intento por estudiar la estructura de la producción agrícola regional y un ensayo por medir la sensibilidad de los estados fronterizos con respecto al mercado externo e interno utilizando modelos del análisis regional, tratando de ir más allá de la pura descripción, buscando inferir a través de un estudio descriptivo, una explicación más general sobre los mecanismos intervinientes. De acuerdo a los resultados de este análisis en el Estado de Baja California, se sugiere un alto grado de integración con respecto al exterior, lo cual se manifiesta en menor proporción en la agricultura de riego de las entidades de Tamaulipas y Nuevo León, lo que nos lleva a sugerir la importancia que tiene analizar en una secuencia similar los distritos de riego fronterizos.

  2. Impactos Ambientais das Atividades Agrícolas em Roraima. = Environmental Impacts of Agriculture Activity in Roraima State.

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    Valdinar Ferreira Melo

    2008-07-01

    Full Text Available A agricultura foi a grande responsável pelo processo de colonização do Brasil. No entanto, estas atividades se desenvolveram ás expensas de ações negativamente impactantes ao meio ambiente. Este trabalho tem com objetivo abordar os impactos ambientais causados pela atividade agrícola no estado de Roraima, despertando o interesse da comunidade para o uso de uma agricultura fundamentada no conceito de sustentabilidade. A prática agropecuária no Brasil, inicialmente de forma empírica, sem muito conhecimento e preocupação com seus efeitos no ambiente, causou a dizimação de grande parte das florestas e a biodiversidade, mas, também, possibilitou a ocupação da terra e a definição dos limites territoriais brasileiros, definindo-se como de grande importância para a sustentação da economia, imprimindo ao Brasil sua vocação agrícola. A atividade nos anos 60 foi concebida para a validação de pacotes tecnológicos importados, contribuiu para a execução de práticas socialmente excludentes e ambientalmente danosas, com reflexos positivos na produção agrícola e comércio de insumos, à custa da implantação de sistemas monoculturais, com motomecanização, irrigação e emprego intensivo de fertilizantes químicos e pesticidas. A impropriedade ambiental deste modelo originou movimentos que culminaram com a conscientização para estas questões, tendo como respostas a elaboração de instrumentos técnicos e jurídicos, e formulação de propostas para avaliar e mitigar os impactos ambientais e modificar as ações humanas, tornando-as mais condizentes com novos paradigmas da sociedade. Em Roraima, esta atividade sofre uma nova mudança, onde as técnicas primitivas de exploração agrícola começam a ser substituídas por atividades tecnificadas com o uso intensivo de tecnologias, com risco de improbidade ambiental que pode culminar com a degradação do meio, caso não haja uma perícia profunda das caracter

  3. Biodegradación de diesel mexicano por un consorcio de bacterias de un suelo agrícola

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    Santiago Cardona

    2003-01-01

    Full Text Available Se realiza la biodegradación de diesel presente en agua por medio de microorganismos de un suelo agrícola. Se determina la cinética de biotransformación y adsorción del diesel para su aplicación en los proyectos de saneamiento de suelos y acuíferos contaminados con diesel. Se presenta la metodología y los resultados de la biodegradación y la adsorción del diesel contenido en agua sintética así como la caracterización del suelo de cultivo seleccionado para el estudio. La degradación se realiza utilizando los microorganismos nativos del suelo de cultivo seleccionado, al cual se le suministra nitrógeno como nutriente y sin él. El peróxido de hidrógeno se suministra como fuente de oxígeno. Por último se presentan los análisis de las cinéticas que determinan la volatilización del diesel. Con los resultados obtenidos se determinan las ecuaciones cinéticas de degradación, adsorción y se calcularon las constantes de velocidad.

  4. Hongos de importancia agrícola presentes en moscas de la fruta del valle de Ica, Perú

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    Carlos E. Tipismana

    2013-05-01

    Full Text Available El objetivo del presente trabajo fue aislar e identificar hongos de especímenes de moscas de la fruta de los géneros Ceratitis (Macleay y Anastrepha (Schiner, del valle de Ica, Perú. Se aislaron hongos pertenecientes a los géneros Alternaria, Aspergillus, Cladosporium, Mucor, Penicillium, Rhizoctonia, Rhizopus y Trichoderma;así como levaduras y micelios estériles. Los recuentos de hongos presentaron rangos entre 8x103 a 8x104 UFC/g para el género Ceratitis; y 7x103 a 7x104 UFC/g para el género Anastrepha. El IVI% (Índice de Valor de Importancia demostró que Cladosporium es el género con mayor valor ecológico con un 78,05%. El Índice de Similitud de especies de hongos entre ambos géneros de mosca de la fruta analizados fue 0,5. Los resultados obtenidos confirman la presencia de hongos en moscas de la fruta; y se deduce el posible impacto de estos dípteros en el área agrícola como potenciales agentes vectores de enfermedades fúngicas para los cultivos locales de importancia económica.

  5. Produção e manejo agrícola: impactos e desafios para sustentabilidade ambiental

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    João Fernando Zamberlan

    2014-01-01

    Full Text Available O desenvolvimento econômico e social de uma região deve estar baseado nos princípios da sustentabilidade ambiental, pois, não sendo assim, corre-se o risco de se deixar para as gerações futuras uma herança de escassez e miséria. Portanto, este trabalho procurou identificar os tipos de produção e manejos dados às áreas agrícolas. Foi realizado com produtores de hortifrutigranjeiros dos municípios de Silveira Martins, Nova Palma e Ivorá, no Rio Grande do Sul, selecionados por sua área territorial encontrar-se inserida nas encostas da Serra Geral, cuja fragilidade ambiental é maior. Foram aplicados questionários do tipo fechado a todos os produtores de hortifrutigranjeiros dos referidos municípios com base em listas fornecidas pelas secretarias de agricultura municipais e Condesus. Concluiu-se que a maioria dos cultivos se dá nas encostas pela própria topografia regional. A maioria dos produtores conduz suas atividades para produção e comércio e são majoritariamente conscientes dos riscos e interessados em projetos que viabilizem a unidade de produção de forma sustentável.

  6. Ordem privada e reforma agrária em Nestor Duarte Nestor Duarte on private order and agrarian reform

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    Osmir Dombrowski

    2000-01-01

    Full Text Available A proposta pioneira de uma lei de reforma agrária apresentada no Congresso em 1947 por Nestor Duarte é submetida a uma análise que permite trazer à tona traços fundamentais do pensamento de um dos precursores da sociologia política no Brasil. Argumenta-se que para Nestor Duarte a intervenção na vida nacional para superar a ordem privada é necessária, mas não pode ser realizada por via autoritária.The pioneering proposal of a agrarian reform law put forward in the Brazilian Congress in 1947 by Nestor Duarte is studied through an analysis that brings to the fore primary features of the thought of one of the founders of political sociology in Brazil. It is argued that for Nestor Duarte the intervention in the national life aiming at surpassing the private order is necessary but can not be made in an authoritarian way.

  7. Uso de plaguicidas en cultivos agrícolas como herramienta para el monitoreo de peligros en salud

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    Virya Bravo Durán

    2013-03-01

    Full Text Available Costa Rica ha incrementado el uso de plaguicidas de mayor toxicidad, debido entre otras cosas al desarrollo de plagas más resistentes y la necesidad que tienen algunos productos agrícolas de exportación de mantener su posición en el mercado internacional. El ser humano al entrar en contacto con los plaguicidas puede experimentar efectos adversos en su salud desde agudos hasta crónicos que se manifiestan en diferentes grados. Para generar indicadores de peligro en salud en algunos cultivos por el uso de estas sustancias, se utilizaron la cantidad de plaguicidas aplicada y su toxicidad. Los datos de uso se recopilan directamente de los productores, a través de un cuestionario, los ingredientes activos identificados se caracterizaron por su toxicidad y se clasificaron por la manifestación de los efectos. Se calculó como indicador la cantidad de plaguicidas aplicada (kg ia/ha/año por las clases de toxicidad consideradas más peligrosas: 1. Efectos de toxicidad aguda en grado de alto a extremo y 2. Tres o más efectos crónicos positivos. Se recomienda vigilar el uso de bromuro de metilo, metam sodio, terbufos, etoprofos, endosulfan, MCPA y carbofuran por toxicidad aguda de alta a extrema y mancozeb, paraquat, diazinon, 2,4-D y carbofuran por efectos crónicos.  

  8. SILICON CARBIDE GRAIN BOUNDARY DISTRIBUTIONS, IRRADIATION CONDITIONS, AND SILVER RETENTION IN IRRADIATED AGR-1 TRISO FUEL PARTICLES

    Energy Technology Data Exchange (ETDEWEB)

    Lillo, T. M.; Rooyen, I. J.; Aguiar, J. A.

    2016-11-01

    Precession electron diffraction in the transmission electron microscope was used to map grain orientation and ultimately determine grain boundary misorientation angle distributions, relative fractions of grain boundary types (random high angle, low angle or coincident site lattice (CSL)-related boundaries) and the distributions of CSL-related grain boundaries in the SiC layer of irradiated TRISO-coated fuel particles. Two particles from the AGR-1 experiment exhibiting high Ag-110m retention (>80%) were compared to a particle exhibiting low Ag-110m retention (<19%). Irradiated particles with high Ag-110m retention exhibited a lower fraction of random, high angle grain boundaries compared to the low Ag-110m retention particle. An inverse relationship between the random, high angle grain boundary fraction and Ag-110m retention is found and is consistent with grain boundary percolation theory. Also, comparison of the grain boundary distributions with previously reported unirradiated grain boundary distributions, based on SEM-based EBSD for similarly fabricated particles, showed only small differences, i.e. a greater low angle grain boundary fraction in unirradiated SiC. It was, thus, concluded that SiC layers with grain boundary distributions susceptible to Ag-110m release were present prior to irradiation. Finally, irradiation parameters were found to have little effect on the association of fission product precipitates with specific grain boundary types.

  9. Aerodinámica de la corriente de aire de un pulverizador agrícola con ventilador centrifugo

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    Mario Ignacio Herrera Prat

    2009-01-01

    Full Text Available Las contaminaciones medioambientales debido a que las gotas del pesticida no alcanzan el blanco y el creciente aumento en las aplicaciones se han vuelto un problema de salud medioambiental. En la aplicación de defensivos agrícolas a los frutales los pulverizadores más utilizados son los que se auxilian de corriente de aire para el traslado de la gota al árbol. Los ventiladores axiales con salida radial es el esquema más extendido, aunque con éxito también se emplean los ventiladores centrífugos en la construcción de los pulverizadores. La aerodinámica de la corriente de aire es la que decide en la calidad de la aplicación y el régimen de trabajo en este equipo. En el trabajo se estudia la aerodinámica de la corriente de aire del pulverizador "MARTIGNANI"5 que utiliza el ventilador centrífugo "MAJOR"5 que distribuye el aire en cuatro salidas. En el estudio se determinara la velocidad del aire, su uniformidad, caudal en las salidas y se analiza la corriente de aire aplicando modelos matemáticos. Se caracteriza la aerodinámica del pulverizador para fundamentar regimenes de trabajo racionales.

  10. Análisis de investigaciones realizadas para modelar la compactación del suelo agrícola

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    Omar González Cueto

    2011-01-01

    Full Text Available La compactación del suelo provocada por el tránsito de la maquinaria, es un problema que afecta las áreas de producción agrícola. Su modelación permite implementar estrategias de manejo del suelo y la maquinaria. Este trabajo tiene como objetivo analizar las principales características que presentan los métodos empleados para modelar la compactación del suelo. Los resultados muestran que el método más preciso para la modelación de la compactación del suelo es el Método de Elementos Finitos. Los modelos para la simulación de la compactación del suelo difieren de los desarrollados para simular el desempeño de neumáticos o del vehículo debido a que en la modelación del contacto, generalmente el neumático no se representa, sólo se simula el efecto de la presión sobre un área del suelo con forma preestablecida.

  11. Capacidad dispersiva de Ceratitis capitata (Diptera: Tephritidae entre valles agrícolas en San Juan, Argentina

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    Leonardo M. DÍAZ

    2008-01-01

    Full Text Available Ceratitis capitata (Wiedemann, díptero tefrítido cosmopolita originario del norte de África, es la principal plaga de los frutales en muchos países de América. El objetivo de este trabajo fue conocer las características de la capacidad de dispersión de Ceratitis capitata , mediante la liberación de moscas estériles en condiciones de campo, con el propósito de predecir las posibles invasiones de valles agrícolas vecinos. Se liberaron 54.000 moscas estériles marcadas de ambos sexos, en localidades del valle de Tulum, cercanas a los ingresos de los valles de Ullum y Zonda. Para el monitoreo del vuelo dispersivo se instalaron trampas Jackson y Mc Phail. Se capturaron 1.213 adultos durante el periodo de muestreo. No hubo propagación de los adultos liberados desde el valle de Tulum a los valles de Ullum y Zonda. La presencia de hospederos, posición geográfica de cada Quebrada y la orientación respecto al viento predominante, podrían explicar la diferencia de difusión entre ambas Quebradas. La dispersión duró cinco semanas. La distancia media de los adultos liberados fue de 3.764 m (S= 2.897 m sin encontrar diferencias entre ambos sexos.

  12. Masculinidad, riesgos y padecimientos laborales. Jornaleros agrícolas del poblado Miguel Alemán, Sonora

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    José Eduardo Calvario Parra

    2007-01-01

    Full Text Available Los varones tienden a omitir o minimizar los daños causados por el trabajo, pues, como hombres, los consideran una naturalización de su desempeño laboral, y, por tanto, asocian la manera masculina de conducirse con ideas de mayor fortaleza e invulnerabilidad ante los riesgos y padecimientos laborales. El presente artículo explora las vivencias de los jornaleros agrícolas del poblado Miguel Alemán (PMA, en Sonora, en los procesos de salud-enfermedad y la construcción social de la masculinidad dominante. El objetivo principal es documentar las prácticas de autoatención y autocuidado de los varones de la región y los costos para la salud en un contexto de orden de género. Después de revisar los postulados teóricos utilizados, se analizan casos de accidentes de trabajo (como la intoxicación por el agroquímico cianamida hidrogenada, las hemorroides y el efecto de la relación entre la idea de una inmunidad subjetiva (IS y la identidad masculina, frente a la enfermedad y el peligro. El artículo permite acercarse a los procesos microsociales con enlaces empírico-metodológicos de los ámbitos laboral y doméstico, y describe etnográficamente prácticas y discursos de los actores y actrices.

  13. Violencia laboral contra jornaleras agrícolas en tres comunidades del noroeste de México

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    Ma. del Carmen Arellano Gálvez

    2014-01-01

    Full Text Available El objetivo de este artículo es analizar las formas de violencia laboral contra mujeres jornaleras agrícolas en tres comunidades de Sinaloa, Sonora y Baja California, para lo que se utilizó una metodología cualitativa, a través de entrevistas grupales que se les hicieron a ellas. Los resultados señalan que las trabajadoras reconocen la violación a sus derechos laborales, como no contar con servicios médicos para ellas y sus hijos, ni ingresos por faltar al trabajo cuando éstos enferman y menos opciones laborales durante el embarazo. A diario viven el acoso y el hostigamiento ejercido por hombres posicionados en distintas jerarquías laborales, pero no son pasivas ante la violencia, ya que diseñan estrategias de autocuidado. Otras se organizan para brindar asesoría a mujeres sobre sus derechos laborales y las acompañan en los procesos de denuncia y búsqueda de justicia.

  14. Intermediarios laborales en Morelos: abasto de jornaleros agrícolas en el centro y noroeste de México

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    Adriana Saldaña Ramírez

    2014-01-01

    Full Text Available La localidad de Tenextepango, en el esta- do de Morelos, se constituyó como centro de contratación de jornaleros agrícolas pa- ra labores en parcelas de pequeños pro- ductores de la zona desde los años sesenta. Sin embargo, en la primera década del si- glo XXI es también fuente de abasteci- miento de trabajadores para agroexporta- doras en Sinaloa y Sonora. Se analiza aquí la operación de los distintos tipos de inter- mediarios laborales que ahí se concentran y que vinculan a empleados y empleadores geográfi camente dislocados. Se compara a los “capitanes” que movilizan jornaleros para Morelos, Hidalgo, Puebla y Michoa- cán; y a los “mayordomos” que abastecen a productores en el noroeste del país. El es- cenario se complejiza más con la presencia de Estado que facilita el traslado de jorna- leros a ciertos mercados de trabajo.

  15. Precaución, riesgo y sostenibilidad en los organismos agrícolas modificados genéticamente Precaución, riesgo y sostenibilidad en los organismos agrícolas modificados genéticamente

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    J. David Tábara

    2003-01-01

    Full Text Available El cultivo y la comercialización de Organismos Agrícolas Modificados Genéticamente (0MG es origen de multitud de importantes polémicas sociales, económicos y ecológicas, en cuya resolución a menudo se reclama la incorporación del principio y de prácticas de precaución. Este artículo introduce y analiza algunas de estas discusiones a partir de la perspectiva aportada por el proyecto europeo Precautionary Expertise for GM Crops (PEG sobre la aplicación de la precaución en el desarrollo y la comercialización de OMG agrícolas. A partir del material recogido en el caso español, los autores argumentan que gran parte de los desacuerdos que surgen de en la interpretación y aplicación de la precaución con relación a los OMG derivan de la adopción de una perspectiva más o menos reduccionista, o más o menos sistémica, tanto en la evaluación y regulación de los riesgos como en la bondad, los costes o los beneficios de su utilización. Por ello es posible detectar analíticamente, paro el caso español, una clara oposición entre aquellas interpretaciones de la precaución caso por caso, de aquellas que sostienen la necesidad de aplicar prácticas de evaluación y de gestión basadas en una precaución sistémica, más cercano a los principios y los postulados políticos de la sostenibilidad.The debate over GMO crops and their commercialisation becomes the source of a large number of conflicts with important social, economic and ecologic consequences the resolution of which often calls for the application of a precautionary approach and of the precautionary principle. This article introduces and analyses such discussions, and does so within the framework provided by the EU project Precautionary Expertise for GM (PEG. Based on first material gathered for the Spanish case study, the authors argue that a large majority of the disagreements around practical application of precaution over agricultural GMO in Spain come from a conception

  16. Transformaciones agrícolas y despoblamiento en las comunidades rurales de la Región Pampeana Argentina

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    Stratta Fernández, Ricardo

    2010-07-01

    Full Text Available The aim of this work is to characterise the historical process of agricultural development in the Pampas and to examine —at the same time— the main features of the rural depopulation process. This characterization is accomplished by defining four historical stages, according to four criteria that point out particular aspects in them: 1 external economic conditions; 2 domestic economic policy framework.; 3 the behaviour of the factors of production and innovation; 4 the urban-rural demographic changes. It is proved that one of the most important changes of this historical process has been the loss of rural population. The historical characterization reveals the agricultural change and analyses the effects of rural depopulation and urban concentration. The reflection on these effects will be useful to understand the region better and to raise appropriate local developing policies that will enable the rural communities sustainability.

    El objetivo de este trabajo, es realizar una caracterización del proceso histórico del desarrollo agrícola en la Región Pampeana, examinando al mismo tiempo, los rasgos principales del proceso de despoblamiento rural. La caracterización se realiza definiendo cuatro etapas históricas, de acuerdo a cuatro criterios que marcan las particularidades de cada una de ellas: 1 las condiciones económicas externas; 2 el marco político y económico interno; 3 el comportamiento de los factores de la producción e innovación y 4 las variaciones demográficas urbano-rurales. Se demuestra que una de las alteraciones más importantes de este proceso histórico, ha sido la pérdida de población rural. Desde esta caracterización histórica se ponen de manifiesto las transformaciones agrícolas ocurridas y se analizan los efectos del despoblamiento y la concentración urbana. La reflexión sobre los cambios y efectos ocurridos servirán para entender mejor la región y plantear políticas de desarrollo local

  17. Las técnicas geomáticas aplicadas en la agricultura: El catastro agrícola

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    Dámaso R. Ponvert Delisles

    2012-01-01

    Full Text Available Las técnicas Geomáticas, Geoinformáticas o de Geoinformación, como se prefiera nombrarlas, son un conjunto de tecnologías geoespaciales así como programas informáticos especializados para el análisis de los datos y su representación espacial. Entre las más importantes, destacan la Teledetección, los Sistemas de Información Geográfica (SIG, los Sistemas de Posicionamiento Global (GPS y la Cartografía, así como software para el procesamiento digital y representación CAD entre otros. Hoy en día sería casi imposible gestionar los procesos agrarios sin recurrir al empleo de alguna de estas técnicas. Una de las herramientas cartográficas temáticas fundamentales son los mapas catastrales, definidos como documentos cartográficos que representan los bienes inmuebles de un área agrícola con suficiente detalle espacial para facilitar la gestión a nivel de parcelas, sub-parcelas e incluso a escala intraparcelaria. Precisamente el trabajo tiene como objetivo demostrar la necesidad e importancia del empleo de las herramientas catastrales para lograr una gestión agraria y territorial eficiente. Para ello se hace analiza el avance del catastro como sistema en Cuba, llegando a la concepción contemporánea y se particulariza en los catastros especializados para el sector, mostrando un ejemplo concreto que permite a los directivos y especialistas de las PyMES apreciar sus bondades.

  18. Incertidumbres en el espacio agrícola y proceso urbanizador > en la región de Murcia

    Directory of Open Access Journals (Sweden)

    José Luis Andrés Sarasa

    2004-01-01

    Full Text Available Esta investigación muestra como la adaptación de las estructuras agrarias a los nuevos parámetros socioeconómicos de la vida moderna, pero también de la PAC, propicia la aparición de un proceso urbanizador, por su planificación lo denominamos «resort», que no sólo cambia el uso del suelo agrícola condenado al yermo, sino que impulsa un desarrollo endógeno apoyado en un sistema de empresas caracterizadas por su fuerte especialización, capacidad de atracción, sistemas de información eficaces y amplia división del trabajo para la producción de espacios de ocio con servicios de alta calidad. El trabajo se organiza en dos partes, la primera tiene por objetivo analizar las vicisitudes por las que atraviesa el espacio agrario de la Región de Murcia para llegar a la conclusión de que los «demonios» están tanto dentro como fuera de sus propias estructuras: el desánimo, la atracción de la vida urbana y la especulación del suelo. La aparición de un proceso urbanizador ligado al golf se ve como la acertada salida a la situación. La segunda parte se centra en el proceso urbanizador que surge a modo de una periurbanización que se presenta bajo tres tipologías, periurbanización en sentido literal, periurbanización litoral y periurbanización turística aislada. Aunque toda la atención se centra en la última con frecuencia se recurre a la comparación con las otras dos para destacar los impactos territoriales, sociales, financieros y medioambientales.

  19. Electron microscopic evaluation and fission product identification of irradiated TRISO coated particles from the AGR-1 experiment: A preliminary Study

    Energy Technology Data Exchange (ETDEWEB)

    I J van Rooyen; D E Janney; B D Miller; J L Riesterer; P A Demkowicz

    2012-10-01

    ABSTRACT Post-irradiation examination of coated particle fuel from the AGR-1 experiment is in progress at Idaho National Laboratory and Oak Ridge National Laboratory. In this presentation a brief summary of results from characterization of microstructures in the coating layers of selected irradiated fuel particles with burnup of 11.3% and 19.3% FIMA will be given. The main objective of the characterization were to study irradiation effects, fuel kernel porosity, layer debonding, layer degradation or corrosion, fission-product precipitation, grain sizes, and transport of fission products from the kernels across the TRISO layers. Characterization techniques such as scanning electron microscopy, transmission electron microscopy, energy dispersive spectroscopy, and wavelength dispersive spectroscopy were used. A new approach to microscopic quantification of fission-product precipitates is also briefly demonstrated. The characterization emphasized fission-product precipitates in the SiC-IPyC interface, SiC layer and the fuel-buffer interlayer, and provided significant new insights into mechanisms of fission-product transport. Although Pd-rich precipitates were identified at the SiC-IPyC interlayer, no significant SiC-layer thinning was observed for the particles investigated. Characterization of these precipitates highlighted the difficulty of measuring low concentration Ag in precipitates with significantly higher concentrations of contain Pd and U. Different approaches to resolving this problem are discussed. Possible microstructural differences between particles with high and low releases of Ag particles are also briefly discussed, and an initial hypothesis is provided to explain fission-product precipitate compositions and locations. No SiC phase transformations or debonding of the SiC-IPyC interlayer as a result of irradiation were observed. Lessons learned from the post-irradiation examination are described and future actions are recommended.

  20. Capítulo 5. Instituciones que Podrían Cooperar en los Programas de Investigación de Economía de Producción Agrícola.

    Directory of Open Access Journals (Sweden)

    Beltrán G. Gregorio

    1953-09-01

    Full Text Available Los distintos gobernantes del país siempre han demostrado interés por la agricultura y buena prueba de ello es la copiosa legislación existente, gran parte de la cual nunca se ha llevado a efecto. Poco antes de 1930 se le dio un impulso a la política agrícola al comenzar a fomentar la agricultura por medio de instituciones oficiales y semi-oficiales. Hoy día hay tal vez una excesiva proliferación de instituciones, a tiempo que la estructura agrícola está desorganizada por cuanto hay una confusión de funciones entre ellas. Esto está en desacuerdo con las tendencias modernas de fomento agrícola. Se mencionan las instituciones más importantes dedicadas al fomento de la agricultura que se catalogan en seis diferentes grupos: Institutos Oficiales, Institutos Semi-oficiales, Instituciones Departamentales y Municipales, Cooperativas Agrícolas, Instituciones privadas, Monopolios de Productos Agrícolas, entre otros.

  1. Estudo da sustentabilidade agrícola em município amazônico com análise envoltória de dados

    Directory of Open Access Journals (Sweden)

    Eliane Gonçalves Gomes

    2009-04-01

    Full Text Available O conceito de sustentabilidade agrícola considera diferentes dimensões. Entretanto, tem como base a valorização dos recursos internos dos sistemas agrícolas produtivos, que se traduz pela manutenção desses sistemas de produção e, consequentemente, de sua produtividade, ao longo do tempo. Este artigo tem como objetivo medir a sustentabilidade de produtores agrícolas a partir de modelos Análise de Envoltória de Dados (Data Envelopment Analysis - DEA com restrições aos pesos. Nesta abordagem, além de considerar várias dimensões, a medida de eficiência resultante é calculada de forma relativa. Foi usado um modelo no qual se explora o desempenho econômico-ambiental (variáveis: área total, mão-de-obra, custo, receita bruta, área com mata, para dois períodos de tempo, 1986 e 2002.The definition of agriculture sustainability considers different aspects. Their main values are the productive systems' internal resources, as they are the way to maintain these systems and, consequently, its productivity through time. In this paper we measure rural producers' sustainability with Data Envelopment Analysis models (DEA with weights restrictions. This approach considers multiple dimensions and is a relative measure of efficiency. We used a model in which we explore the economic-environmental performance (variables: total area, employment, costs, net income, forested area, in two periods of time, the years of 1986 and 2002.

  2. PRAPRAG: software para planejamento racional de máquinas agrícolas PRAPRAG: software for rational planning of agricultural machines

    Directory of Open Access Journals (Sweden)

    Erivelto Mercante

    2010-04-01

    Full Text Available O software PRAPRAG é uma ferramenta de escolha de máquinas e implementos agrícolas que apresentam o menor custo por área ou por quantidade produzida, bem como, faz o planejamento de aquisição das máquinas para a propriedade agrícola, do ponto de vista técnico e econômico. Foi utilizada a linguagem de programação Borland Delphi 3.0 e, a partir de prospectos das máquinas e implementos, criou-se um banco de dados onde o usuário pode cadastrar e modificar suas características de uso. O software mostrou-se uma ferramenta útil e uso amigável. O software proporciona maior rapidez, segurança e confiabilidade ao processo produtivo e econômico das propriedades, na seleção e aquisição de conjuntos mecanizados agrícolas, e na determinação de custos com a mão de obra utilizada.The software PRAPRAG is a tool used for choosing agricultural machines and implements that present the lowest cost per area or produced amount, as well as, to it makes the machines acquisition planning for the agricultural property, from both technical and economical points of view. It was used the programming language Borland Delphi 3.0. From the machine and implement handouts, it was created a database where the user can register and modify their characteristics of use. The software showed to be a useful and friendly tool. The software provides high speed, safety and reliability for the productive and economical process of the properties, at the selection and acquisition of agricultural systems, as well as for the determination of costs with the used labor.

  3. Produtividade agrícola e segurança alimentar dos domicílios das regiões metropolitanas brasileiras

    Directory of Open Access Journals (Sweden)

    Lorena Vieira Costa

    2013-12-01

    Full Text Available O crescimento agrícola pode afetar o nível de bem-estar de uma população mediante a possibilidade de elevação da oferta de alimentos, com reflexo em menores preços e na qualidade da dieta das pessoas. Assim, buscou-se, neste trabalho, verificar a relação entre a produtividade agrícola brasileira dos principais itens constituintes da dieta da população e a segurança alimentar dos domicílios das regiões metropolitanas brasileiras. Utilizou-se um modelo de escolha qualitativa, o probit, e dados das Pesquisas de Orçamentos Familiares (POF de 1995-1996, 2002-2003 e 2008-2009 e da pesquisa de Produção Agrícola Municipal (PAM. Foram verificadas importantes relações entre a escolaridade do chefe do domicílio, a presença de pessoas menores de 18 anos na família e o fato de o domicílio obter renda per capita inferior a um salário mínimo e a segurança alimentar. Além disso, o crescimento da produtividade dos grãos, das verduras e legumes e das frutas associou-se à maior probabilidade de segurança alimentar em pelo menos um dos períodos analisados. Conclui-se que os ganhos de produtividade associam-se à maior segurança alimentar domiciliar, porém, em baixas proporções, devido à alta influência de fatores particulares aos domicílios, como escolaridade e renda.

  4. Coccinellidos detectados en trampas de vigilancia agrícola y forestal, temporada 2014-2015, en la región Metropolitana, Servicio Agrícola y Ganadero (SAG.

    Directory of Open Access Journals (Sweden)

    Daniela Rojas

    2016-06-01

    Full Text Available Dentro del Orden Coleópteros, se encuentra la Familia de los Coccinélidos, comúnmente llamadas chinitas o mariquitas. En Chile existen 5 sub-familias, con alrededor de 115 especies (González 2014, las cuales se encuentran distribuidas a lo largo de todo el país. Resulta interesante entonces, dar cuenta de la diversidad de Coccinélidos colectados en trampas de Lobesia botrana, Mosca de la fruta y Vigilancia Agrícola y Forestal, es por ello que en el presente trabajo se entrega un listado y descripción de Coccinélidos colectados en dichas trampas y diferentes morfos por especie. La colecta de coccinélidos se realizó en el Laboratorio Regional de Entomología, R.M. durante la revisión de las trampas, desde agosto del 2014 hasta mayo del 2015. Las chinitas fueron removidas cuidadosamente de los pisos pegajosos de las trampas con la ayuda de herramientas de disección y disolvente histológico Histo-Clear. Fueron montadas en etiquetas de 0,5 por 1,2 cm y fijadas en alfileres entomológicos número 1. La identificación de los Coccinélidos se realizó a nivel de morfoespecie, utilizando las descripciones e ilustraciones de González, 2014. En el caso de ejemplares dudosos, de difícil identificación a nivel de morfoespecie, se realizó genitalia. Este trabajo espera ser un aporte significativo, respecto a mejorar el conocimiento taxonómico, distribución de especies en la región y presencia de morfos de coccinélidos. Los ejemplares colectados son incorporados a la colección de referencia del Laboratorio Regional de Entomología R.M. y se encuentra a disposición de quien lo solicite.

  5. Factores que condicionan la aplicación de buenas prácticas agrícolas: un enfoque cualitativo

    OpenAIRE

    González, Julia; Rodríguez, Elsa Mirta M.

    2010-01-01

    Con el propósito de indagar el potencial desarrollo de Buenas Prácticas Agrícolas en la producción de papa en el sudeste de la provincia de Buenos Aires, se evaluaron las percepciones de los agentes que participan en la producción, comercialización y consumo de este producto mediante técnicas cualitativas. Los resultados permiten concluir que las principales limitaciones son: ciertas características de los productores, la falta de conocimiento de estas prácticas entre los actores estratégicos...

  6. Uso de las imágenes de satélites y los SIG en el campo de la Ingeniería Agrícola

    OpenAIRE

    Dámaso Ponvert Delisles; Andés Lau Quan

    2013-01-01

    Los sistemas de ingeniería agrícola constituyen conjuntos de técnicas y tecnologías que garantizan la producción agropecuaria. Por lo general, ellos producen determinados impactos al medio ambiente, que tienen consecuencias negativas sobre los recursos naturales produciendo huellas en el territorio. En la actualidad se aplican con éxito tecnologías muy eficaces como la Teledetección y, los SIG para identificar la huella espacial de estos impactos y apoyar las decisiones que ayuden a los direc...

  7. Efectos del tlcan sobre el empleo de mano de obra en el sector agrícola de México, 1994-2010

    OpenAIRE

    Yuliana Lechuga Jardínez; José Alberto García Salazar; Marcos Portillo Vázquez; Roberto Carlos García Sánchez

    2014-01-01

    el Tratado de Libre Comercio de América del Norte se implementó en 1994 para solucionar el desempleo de mano de obra en el campo mexicano, sin embargo, actual - mente las zonas rurales del país enfrentan el mismo pro - blema. Se calcularon las fuentes de crecimiento del em - pleo de mano de obra, de 1994 a 2010, con la finalidad de determinar su impacto sobre el sector agrícola de Méxi - co. Los resultados indican que el cambio en la estructura productiva fue desfavorable para el empleo en ge...

  8. Factores que condicionan la aplicación de buenas prácticas agrícolas: un enfoque cualitativo

    OpenAIRE

    González, Julia; Rodríguez, Elsa Mirta M.

    2010-01-01

    Con el propósito de indagar el potencial desarrollo de Buenas Prácticas Agrícolas en la producción de papa en el sudeste de la provincia de Buenos Aires, se evaluaron las percepciones de los agentes que participan en la producción, comercialización y consumo de este producto mediante técnicas cualitativas. Los resultados permiten concluir que las principales limitaciones son: ciertas características de los productores, la falta de conocimiento de estas prácticas entre los actores estratégicos...

  9. Implementación de buenas prácticas agrícolas en el sector papero del sudeste de la provincia de Buenos Aires

    OpenAIRE

    González, Julia

    2009-01-01

    El objetivo general de esta investigación es indagar acerca del potencial desarrollo de Buenas Prácticas Agrícolas en la producción de papa del sudeste de la provincia de Buenos Aires. El estudio utiliza técnicas cuantitativas para describir el comportamiento de las principales variables económicas del mercado papero, y técnicas cualitativas para conocer las percepciones y opiniones de representantes del sector acerca de la temática abordada. Los resultados indican que las principales limitac...

  10. Desempenho agrônomico de soja em função da sucessão de culturas em sistema de plantio direto

    OpenAIRE

    Brandt,Eduardo André; Souza,Luiz Carlos Ferreira de; Vitorino,Antonio Carlos Tadeu; Marchetti,Marlene Estevão

    2006-01-01

    Com o objetivo de avaliar o efeito da rotação ou sucessão de culturas sobre o desempenho agronômico de soja em semeadura direta, foi desenvolvido um experimento em Latossolo Vermelho distroférrico, no Núcleo Experimental de Ciências Agrárias da Universidade Federal de Mato Grosso do Sul, em Dourados MS. O delineamento experimental foi em blocos casualizados com nove tratamentos e quatro repetições. As parcelas mediram 36 m de comprimento por 11 m de largura (396 m²),onde foram semeadas mecani...

  11. Comparación subsector agroindustrial colombiano versus el argentino y potencial de exportación de productos agrícolas a Brasil y Argentina

    OpenAIRE

    Arias Fierro, Rocio del Pilar

    2016-01-01

    Este artículo contiene información sobre la evolución de las exportaciones colombianas a los países miembros del Mercosur. En él se presenta el potencial exportador de productos agrícolas colombianos, profundizando especialmente en los beneficios generados por el acuerdo que en la actualidad se encuentra vigente. Como parte fundamental, se analizan las variaciones que han venido teniendo los mercados, las cuales han generado el déficit de la balanza comercial de Colombia con respecto a B...

  12. Análisis por elementos finitos de cargas de impacto. Estudio de caso de viga de tren de rodaje de remolque agrícola

    OpenAIRE

    Raudel Flores Moreno; Arturo Martínez Rodríguez; Jorge Samá Montes

    2009-01-01

    Las circunstancias que dan lugar a sobrecargas en las máquinas e implementos agrícolas se ven acrecentadas en Cuba debido a exigentes condiciones de los terrenos y características pesadas de los suelos, siendo habituales en la agricultura cubana los ejemplos de máquinas e implementos, tanto de fabricación nacional como de importación, que sufren deformaciones en su estructura o roturas frecuentes en sus órganos de trabajo. La determinación de coeficientes de cargas dinámicas que posibiliten o...

  13. Análisis por elementos finitos de cargas de impacto en elementos estructurales de máquinas agrícolas

    OpenAIRE

    Raudel Flores Moreno; Arturo Martínez Rodríguez; Jorge Samá Montes

    2009-01-01

    Las circunstancias que dan lugar a sobrecargas en las máquinas e implementos agrícolas se ven acrecentadas en Cuba debido a exigentes condiciones de los terrenos y características pesadas de los suelos, siendo habituales en la agricultura cubana los ejemplos de máquinas e implementos, tanto de fabricación nacional como de importación, que sufren deformaciones en su estructura o roturas frecuentes en sus órganos de trabajo. La determinación de coeficientes de cargas dinámicas que posibiliten o...

  14. Producción de plántulas de pimiento morrón (Capsicum annuum L.) en sustratos derivados de residuos agrícolas.

    OpenAIRE

    Pérez López, Hermelindo

    2014-01-01

    Con el propósito de encontrar alternativas y tratar de reducir el impacto ambiental que ocasiona el uso de la turba y otros materiales convencionales, se evaluaron subproductos orgánicos agroindustriales (bagazo de la caña de azúcar, cachaza y cascarilla de café) en combinación con material inorgánicos (tezontle). El objetivo fue caracterizar las propiedades físicas y químicas de mezclas de sustratos basados en residuos agrícolas y evaluar su uso en la producción de plántulas de cinco varied...

  15. El futuro del desarrollo agrícola del Ecuador en el Área de Libre Comercio de las Américas (ALCA)

    OpenAIRE

    Burgos Vera, Bruno, Ing.

    2002-01-01

    De la crisis a la modernización integral, puede ser para el país, uno de los trayectos alternativos hacia el desarrollo integral; pero para el proceso de integración comercial continental (Area de Libre Comercio para las Américas ALCA), a través de la cual se atenderán los requerimientos de nuevos mercados para la producción nacional es por ahora una ruta insustituible. Es evidente la poca productividad, competitividad y calidad del sector agrícola del país; evidencia reflejada en los ba...

  16. Aplicación de la energía renovable en el secado. Estado del arte y su potencial en las producciones agrícolas

    Directory of Open Access Journals (Sweden)

    Raúl Costales

    2010-01-01

    Full Text Available Se introduce el tema del secado solar como una gestión de ingeniería, encaminada en la actualidad a resolver dos grandes problemas; la disminución de los costos de producción de los productos agrícolas y la reducción de emisiones de CO2 a la atmósfera lo que contribuye a disminuir el efecto invernadero que nos afecta globalmente. Se analiza un cúmulo de informaciones que se derivan de diferentes proyectos y sus resultados así como su sensible influencia en las inversiones y procesos tecnológicos.

  17. Obtención de Celulosa a Partir de los Desechos Agrícolas del Banano Production of Cellulose from Banana Plant Agricultural Waste

    OpenAIRE

    G. Canché-Escamilla; J.M. De los Santos-Hernández; S. Andrade-Canto; R. Gómez-Cruz

    2005-01-01

    En este trabajo, se presenta un estudio sobre la factibilidad de obtención de celulosa a partir de residuos agrícolas del banano (pseudotallo y pinzote), usando un procedimiento desarrollado en el Centro de Investigación Científica de Yucatán-México. El proceso consiste en cuatro etapas: hidrólisis ácida, cloración, extracción alcalina y blanqueo. La celulosa se caracterizó mediante termogravimetría, espectroscopía de FTIR y determinación de peso molecular. Se obtuvieron mejores rendimientos ...

  18. Las contradicciones de un mundo globalizado: grandes políticas agrícolas y derecho a la soberanía alimentaria

    OpenAIRE

    Milla Bordera, Pedro José

    2014-01-01

    En un mundo que presume de ser globalizado, el impulso de determinadas políticas agroalimentarias puede generar graves impactos económicos, sociales y ambientales tanto en los países desarrollados como en los subdesarrollados. Estrategias como la liberalización del comercio de productos agrícolas o el productivismo son impulsadas desde los países ricos con el objetivo de hacer pagar a los pequeños la sobreproducción de los grandes. En este sentido, no son pocas las voces que reclaman una glob...

  19. Un proyecto agrícola-industrial en el Río Atoyac: el obispo Gillow y la hacienda de Chautla, Puebla (1877-1914)

    OpenAIRE

    Cecilia Adriana Bautista García

    2003-01-01

    El presente texto analiza la actividad empresarial de Eulogio Gillow, obispo de Oaxaca, amigo personal de Porfirio Díaz, y miembro destacado de la jerarquía eclesial mexicana. Los proyectos hidráulicos, agrícolas e industriales llevados a cabo por el sacerdote en su hacienda de Chautla, tuvieron una connotación social que concilió los intereses económicos del obispo con la problemática de sus trabajadores. En la finca no sólo se hicieron obras hidráulicas relevantes, también se probó maquinar...

  20. Distribución espacial del contenido de materia orgánica de los suelos agrícolas de Zapopan, Jalisco

    OpenAIRE

    Daniel Ibarra Castillo; José Ariel Ruiz Corral; José Germán Flores Garnica; Diego R. González Eguiarte

    2007-01-01

    El objetivo de la presente investigación fue determinar la distribución espacial del contenido de materia orgánica (MO), variable asociada con la fertilidad en los suelos agrícolas, del municipio de Zapopan, Jalisco, México. Se realizaron muestreos georreferenciados de suelo, para su posterior análisis en laboratorio y determinación del contenido de MO. Los resultados del análisis se capturaron en una hoja de cálculo electrónica (Microsoft Excel) para integrar una base de datos georreferenc...

  1. Impactos Socioeconômicos de Reduções nas Perdas Pós-colheita de Produtos Agrícolas no Brasil

    Directory of Open Access Journals (Sweden)

    Cinthia Cabral da Costa

    2015-09-01

    Full Text Available Resumo: Países da América Latina, incluindo o Brasil, apresentam níveis de perdas pós-colheita de produtos agrícolas superiores aos observados em países mais desenvolvidos. O presente estudo teve como objetivo estimar os impactos que a economia brasileira poderia obter caso os níveis destas perdas no País fossem reduzidas para os níveis observados em países de alta renda. Para isto, calculou­-se a redução nas perdas pós-colheita de produtos agrícolas no País e, utilizando a matriz insumo-produto do Brasil, foram estimados os impactos que esta redução poderia causar na economia brasileira, resultante do aumento dos serviços de processamento, transporte e comércio, que seriam incluídos naqueles produtos recuperados. Observou-se que, a preços de 2012, esta redução nas perdas pós­-colheita implicaria em aumento de R$ 9,8 bilhões no valor da produção agrícola. Considerando os impactos diretos, indiretos e de efeito renda, identificou­-se que um aumento na demanda por serviços de processamento, transporte e comércio originado pelo aumento desta oferta, pode elevar o valor da produção da economia em R$ 18 bilhões, o PIB do País em R$ 9,7 bilhões e gerar mais de 300 mil empregos. Tais resultados ilustram que, face à grande importância dos produtos agrícolas para a economia brasileira, a redução nas perdas pós-colheita pode gerar benefícios econômicos substanciais para o País.

  2. Acceptance Test Data for the AGR-5/6/7 Irradiation Test Fuel Composite Defective IPyC Fraction and Pyrocarbon Anisotropy

    Energy Technology Data Exchange (ETDEWEB)

    Helmreich, Grant W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hunn, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Skitt, Darren J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dyer, John A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Schumacher, Austin T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-05-01

    Coated particle composite J52R-16-98005 was produced by Babcock and Wilcox Technologies (BWXT) as fuel for the Advanced Gas Reactor Fuel Development and Qualification (AGR) Program’s AGR-5/6/7 irradiation test in the Idaho National Laboratory (INL) Advanced Test Reactor (ATR). This composite was comprised of four coated particle fuel batches J52O-16-93165B (26%), 93168B (26%), 93169B (24%), and 93170B (24%), chosen based on the Quality Control (QC) data acquired for each individual candidate AGR-5/6/7 batch. Each batch was coated in a 150-mm-diameter production-scale fluidized-bed chemical vapor deposition (CVD) furnace. Tristructural isotropic (TRISO) coatings were deposited on 425-μm-nominal-diameter spherical kernels from BWXT Lot J52R-16-69317 containing a mixture of 15.5%-enriched uranium carbide and uranium oxide (UCO). The TRISO coatings consisted of four consecutive CVD layers: a ~50% dense carbon buffer layer with 100-μm-nominal thickness, a dense inner pyrolytic carbon (IPyC) layer with 40-μm-nominal thickness, a silicon carbide (SiC) layer with 35-μm-nominal thickness, and a dense outer pyrolytic carbon (OPyC) layer with 40-μm-nominal thickness. The TRISO-coated particle batches were sieved to upgrade the particles by removing over-sized and under-sized material, and the upgraded batches were designated by appending the letter A to the end of the batch number (e.g., 93165A). Secondary upgrading by sieving was performed on the A-designated batches to remove particles with missing or very-thin buffer layers that were identified during previous analysis of the individual batches for defective IPyC, as reported in the acceptance test data report for the AGR-5/6/7 production batches [Hunn et al. 2017]. The additionally-upgraded batches were designated by appending the letter B to the end of the batch number (e.g., 93165B).

  3. A "infância desamparada" no asilo agrícola de Santa Isabel: instrução rural e infantil (1880 - 1886

    Directory of Open Access Journals (Sweden)

    Schueler Alessandra Frota Martinez de

    2000-01-01

    Full Text Available O presente trabalho trata da criação da Associação Protetora da Infância Desamparada, na Província do Rio de Janeiro, nos anos 1880, e as suas propostas de promover a instrução primária e a educação agrícola destinadas às chamadas crianças pobres do Império. Para tanto, levou-se em consideração os debates sobre a difusão da instrução elementar, o trabalho e a reatualização das políticas de controle social. Estas políticas estiveram presentes entre as preocupações e os objetivos dos sócios fundadores e políticos do Império e sinalizaram para um projeto de educação asilar, no qual a economia agrícola surgia como base da construção nacional. Para compreender essas questões, o artigo detém-se na análise do Asylo Agrícola de Santa Isabel, criado pela Associação e inaugurado em 1886. Busca-se caracterizar: sua arquitetura, os espaços construídos e áreas externas; as crianças para lá enviadas, sua naturalidade, sexo e condição social; e o ensino ministrado, os saberes difundidos, disciplina de caráter religioso, recursos a prêmios como emulação e trabalho no campo. Conclui-se com a afirmação de que a tentativa de estabelecer uma política de educação moral e religiosa, aliada à instrução elementar e ao ensino voltado ao trabalho rural, com o intuito de conservação de uma mão-de-obra dependente nas fazendas agrícolas, consistiu nos fundamentos e objetivos principais da Associação Protetora da Infância Desamparada.

  4. A Economia agrária do Algarve, na transição do Antigo Regime para o Liberalismo (1750-1836)

    OpenAIRE

    Mesquita, José Carlos Vilhena

    2009-01-01

    Artigo científico sobre a economia agrária do Algarve, desde o Pombalismo a Setembrismo, publicado na revista «ESTUDOS III», editada pela Universidade do Algarve, em 2009. A situação económica da agricultura algarvia foi sempre deficitária, mercê dos baixos índices de produtividade e de rendimento, suscitados pela desigual distribuição social da propriedade, pelo baixo investimento financeiro e pelo atraso científico-tecnológico, que – desde o período de reestruturação político...

  5. Incentivos a la innovación de la biotecnología agrícola-alimentaria en México

    OpenAIRE

    Marcela Amaro-Rosales; Daniel Hugo Villavicencio-Carbajal

    2015-01-01

    En el artículo analizamos la innovación biotecnológica relacionada con los sectores agrícola y alimentario en México. Tomamos en cuenta las políticas públicas, las leyes y las reglamentaciones; la dinámica del sector y del merado. Asimismo, analizamos la forma en la que las empresas agro-alimentarias pueden aprovechar los insumos de conocimiento científico y tecnológico que ofrece la biotecnología. La principal conclusión es que actualmente el marco institucional regulatorio y la dinámica del...

  6. Manutenção de tratores agrícolas e condição técnica dos operadores

    OpenAIRE

    Reis, Gustavo N. dos [UNESP; LOPES, Afonso; Furlani,Carlos E. A.; Silva, Rouverson P. da [UNESP; Danilo C.C. Grotta; Câmara,Felipe T. da

    2005-01-01

    A manutenção dos tratores agrícolas pode ser considerada um conjunto de procedimentos que visa a manter o equipamento nas melhores condições de funcionamento, propiciando aumento da vida útil, evitando danos prematuros, eliminando os já observados e concorrendo para maior segurança no trabalho. Essa conduta, apesar de simples, exige atenção e cuidado semelhante ou até maior quando comparado a outro veículo automotor. O presente trabalho teve por objetivo analisar a regularidade e a qualidade ...

  7. Efecto ambiental de agroquímicos y maquinaria agrícola en cultivos transgénicos y convencionales de algodón

    OpenAIRE

    Giovanni Reyes; Alejandro Chaparro-Giraldo; Kelly Ávila

    2010-01-01

    Título en inglés: Environmental effects of agrochemicals and agricultural machinery in transgenic and conventional crops cotton Resumen La producción de alimentos se basa en el uso de diferentes tecnologías agrícolas, que pueden derivar en conflictos entre medioambiente y agricultura. Es significativo estudiar el impacto ambiental de las nuevas tecnologías aplicadas a la agricultura, la más importante de las cuales es la transgénesis. Este trabajo se realizó en la zona algodonera del ...

  8. Análisis de la sustentabilidad en sistemas agrícolas con pequeña irrigación en el municipio de Tepeaca, Puebla

    OpenAIRE

    Neri Noriega, René

    2012-01-01

    En méxico los sistemas agricolas con riego a pequeña escala resultan ser de gran importancia para las familias rurales. De estos se obtienen productos alimenticios, ingresos, empleos y servicios. Sin embargo, el mal manejo del recurso agua esta provocando cambios en el sistema que afectan su funcionalidad. Con el objeto de analizar el estado de sustentabilidad, se estudiaron dos agrosistemas que usan agua del subsuelo en San Pablo, Actipan, Tepeaca en el estado de Puebla. Estos sistemas agríc...

  9. Primer registro de Allomyces neomoniliformis (Chytridiomycota y Dictyuchus missouriensis (Oomycota aislados de un suelo agrícola (Buenos Aires, Argentina

    Directory of Open Access Journals (Sweden)

    Mónica M. Steciow

    2001-01-01

    Full Text Available Allomyces neomoniliformis y Dictyuchus missouriensis fueron aislados de un suelo agrícola conteniendo materia orgánica (hojas, raíces y tallos en Argentina. Ambas especies son citadas por primera vez para la Argentina y por segunda vez para Sudamérica, siendo el hallazgo más austral para el hemisferio occidental. Constituye el segundo aislamiento en Argentina de especies del género Allomyces y Dictyuchus. Se realizan consideraciones acerca de la distribucion de ambas especies

  10. "De regreso al futuro” Arte Vitivinícola, Religión y Ciencia en Nuevas Sociedades Agrícolas.

    Directory of Open Access Journals (Sweden)

    Fabio Aldemar Gómez Sierra

    2009-10-01

    Full Text Available La vitivinicultura posee un patrimonio mitológico que el arte y lareligión han expresado profundamente y que la ciencia moderna complementa. Esta riqueza simbólica surgió en un contexto agrícola y por ende sagrado. Explorar esta iconografía antigua y nueva en Boyacá, implica valorar cimientos sociales enmarcados por una mezcla y una complementariedad religiosa, cuyagenuina expresión es la agricultura; indicador simbiótico de la vida en altitud. El proyecto vitivinícola del Valle del Sol, guía estapercepción.

  11. Uso de las imágenes de satélites y los SIG en el campo de la Ingeniería Agrícola

    OpenAIRE

    Dámaso Ponvert Delisles; Andés Lau Quan

    2013-01-01

    Los sistemas de ingeniería agrícola constituyen conjuntos de técnicas y tecnologías que garantizan la producción agropecuaria. Por lo general, ellos producen determinados impactos al medio ambiente, que tienen consecuencias negativas sobre los recursos naturales produciendo huellas en el territorio. En la actualidad se aplican con éxito tecnologías muy eficaces como la Teledetección y, los SIG para identificar la huella espacial de estos impactos y apoyar las decisiones que ayuden a los direc...

  12. 中越婚姻制度比较研究%A Comparison Study on China and Vietnam's Marriage SystemsWANG Chnang-hai,ZHANG Jing

    Institute of Scientific and Technical Information of China (English)

    汪传海; 张静

    2009-01-01

    As the establishment of China-ASEAN Free Trade Area, China and Vietnam's economic and trade intercourse, as well as personnel exchanges become closer, the number of transnafional marriage grows sharply. Against this background, and according to a systematic comparison study on China and Vietnam's marriage laws, I here summarizes the similarities and differences of two country's marriage laws, learns the successful experience of legislation, and puts emphasis on assessment of differences in this paper, and help to exchange between the two peoples more convenient.%随着中国一东盟自由贸易区的建立,两国的经贸、人员交往日益密切,跨国婚姻迅猛增长.在此背景下,对中越两国婚姻法进行系统的比较研究,概括两国婚姻法异同及借鉴成功的立法经验,着重对不同之处进行析评,以期方便两国人民的交往.

  13. A disputa político-ideológica entre a reforma agrária redistributiva e o modelo de reforma agrária de mercado do Banco Mundial (1994-2005 The political-ideological dispute between redistributive agrarian reform and the market land reform model of the World Bank (1994-2005

    Directory of Open Access Journals (Sweden)

    João Márcio Mendes Pereira

    2005-12-01

    Full Text Available O trabalho analisa a disputa político-ideológica entre o modelo de reforma agrária de mercado (MRAM do Banco Mundial (BM e a reforma agrária redistributiva. Argumenta-se que o cerne dessa disputa reside no fato de que esse modelo foi criado para substituir o papel desapropriatório e redistributivo do Estado. Mostra-se que, em todos os países onde foi implementado (África do Sul, Colômbia, Guatemala e Brasil, as supostas vantagens atribuídas ao MRAM sobre a reforma agrária não se materializaram.The work analyses the political-ideological dispute between the market land reform model (MLRM of the World Bank (WB and redistributive agrarian reform. We argue that the core of this dispute lies in the fact that the MLRM was created to substitute the expropriative and redistributive role of the State. We show that in all countries where it was implemented (South Africa, Colombia, Guatemala and Brazil, the alleged advantages attributed to the MLRM over agrarian reform did not materialize.

  14. “proyecto de inversión para la creación de una consultora agrícola técnica financiera en el cantón Daule”

    OpenAIRE

    Abad Barzola, Mary; Bonifaz Vicuña, Gabriela; Ludeña Moreira, María; Valdiviezo Valenzuela, Patricia

    2013-01-01

    El desarrollo que ha mostrado el sector agrícola en nuestro país hace que cada vez sean más importantes los servicios que se brindan en torno a esta área. Por otro lado los continuos cambios en la agricultura como es la aparición de nuevas tendencias de manejo de suelo y cultivo, a demás de la tecnificación de estudios y herramientas para mejorar la producción agrícola. Mediante la creación de una consultora agrícola técnica financiera en el cantón Daule se pretende satisfacer la demanda de s...

  15. Estudio comparativo de un indicador de desertificación para zonas agrícolas semi-áridas, Cuenca del Guadalentín, Sureste de España

    Directory of Open Access Journals (Sweden)

    E. Hernández Laguna

    2000-01-01

    Full Text Available El trabajo calcula un indicador de desertificación para zonas agrícolas, determinado por la ratio entre producción agrícola total y el consumo de fertilizantes inorgánicos (N, P y K, para la agricultura española, para la Región de Murcia y dentro de ésta para el Valle del río Guadalentín. Los resultados muestran como este indicador es válido para determinar procesos de desertificación provocados por prácticas agrícolas insostenibles e inducir estudios más profundos de degradación del suelo.

  16. The Agr-like quorum-sensing system regulates sporulation and production of enterotoxin and beta2 toxin by Clostridium perfringens type A non-food-borne human gastrointestinal disease strain F5603.

    Science.gov (United States)

    Li, Jihong; Chen, Jianming; Vidal, Jorge E; McClane, Bruce A

    2011-06-01

    Clostridium perfringens type A strains producing enterotoxin (CPE) cause one of the most common bacterial food-borne illnesses, as well as many cases of non-food-borne human gastrointestinal disease. Recent studies have shown that an Agr-like quorum-sensing system controls production of chromosomally encoded alpha-toxin and perfringolysin O by C. perfringens, as well as sporulation by Clostridium botulinum and Clostridium sporogenes. The current study explored whether the Agr-like quorum-sensing system also regulates sporulation and production of two plasmid-encoded toxins (CPE and beta2 toxin) that may contribute to the pathogenesis of non-food-borne human gastrointestinal disease strain F5603. An isogenic agrB null mutant was inhibited for production of beta2 toxin during vegetative growth and in sporulating culture, providing the first evidence that, in C. perfringens, this system can control production of plasmid-encoded toxins as well as chromosomally encoded toxins. This mutant also showed reduced production of alpha-toxin and perfringolysin O during vegetative growth. Importantly, when cultured in sporulation medium, the mutant failed to efficiently form spores and was blocked for CPE production. Complementation partially or fully reversed all phenotypic changes in the mutant, confirming that they were specifically due to inactivation of the agr locus. Western blots suggest that this loss of sporulation and sporulation-specific CPE production for the agrB null mutant involves, at least in part, Agr-mediated regulation of production of Spo0A and alternative sigma factors, which are essential for C. perfringens sporulation.

  17. Impacto de las pruebas de tractores agrícolas en México: determinación de potencia a la toma de fuerza, levante hidráulico, cabinas y marcos de seguridad

    Directory of Open Access Journals (Sweden)

    Alma Velia Ayala Garay

    2013-01-01

    Full Text Available El tractor agrícola está diseñado para transportar o transmitir potencia a herramientas cuando sea necesario operarlos. Con el fin de determinar las características básicas de los equipos, se han desarrollado estándares internacionales y nacionales. En México los ensayos de tractores toman como referencia los métodos de prueba establecidos en las normas NMX-O-169-SCFI-2002 “Tractor agrícola - potencia a la toma de fuerza” y “Tractor - Potencia y fuerza de levante hidráulico al enganche a los tres puntos en la capacidad de levante a los 610 mm.” NMX-O-207-SCFI-2004 y la norma NMX-O-181-SCFI-2003 “Tractor agrícola – cabinas y marcos de protección de tractores agrícolas y forestales–especificaciones y método de prueba (prueba estática”, estas forman parte del proceso de certificación de maquinaria que realiza el OCIMA-INIFAP, el objetivo del presente es realizar un análisis de los resultados obtenidos de la evaluación de los tractores agrícolas a través de la potencia a la toma de fuerza, fuerza de levante hidráulico al enganche a los tres puntos en la capacidad de levante a los 610 mm y cabinas y marcos de protección de tractores agrícolas en el laboratorio de pruebas del CENEMA como parte del proceso de certificación.

  18. Department of Agr

    African Journals Online (AJOL)

    USER

    2017-04-03

    Apr 3, 2017 ... The study examined the Agricultural Information and communication networks among poultry farmers in ... examine the communication sources and networking available to poultry farmers. Descriptive ..... Elsevier Sci. Publ.,.

  19. Plan de Organización de los Servicios de Fomento Agrícola en Colombia-Organización General

    Directory of Open Access Journals (Sweden)

    Chavarriaga Misas Eduardo

    1941-02-01

    Full Text Available Relativamente nueva es la orientación agrícola de nuestro país, y más nuevo aún el interés por encauzar esa agricultura por senderos que la conduzcan a la prosperidad y bienestar económico. Y por eso el problema que se nos presenta al querer organizar ese ramo en Colombia, que no podemos copiar íntegramente los métodos seguidos en otros países de mejores recursos y mayor adelanto, ni echar mano de sistemas empolvados por décadas de años. Indudablemente la organización agrícola de Colombia ha sido influenciada en su mayor parte por los sistemas seguidos en Estados Unidos. Sin demorarme a exponer razones, no creo que sea un error y se identifica con mi modo de pensar: métodos modernos organizados bajo un plan modesto y acomodado a la realidad.

  20. Monotonía, aislamiento y atraso agrícola. Descripciones de viajeros del siglo XIX e historia agraria de la Sabana de Bogotá (Colombia

    Directory of Open Access Journals (Sweden)

    Katherinne Giselle Mora Pacheco

    2015-01-01

    Full Text Available Diferentes obras de Historia Agraria reproducen una descripción similar de la Sabana de Bogotá (Colombia durante el siglo XIX: vocación agrícola desde la Colonia; extensos campos cubiertos de trigo y cebada; reemplazo abrupto de cultivos por ganadería; crisis de la agricultura vinculada con las bonanzas agroexportadoras y la demanda de productos tropicales que no podían obtenerse en altitudes superiores a 2000 metros. Este artículo analiza cómo esta perspectiva ha perpetuado las descripciones de viajeros que visitaron la región durante el siglo XIX, basadas en sus orígenes, objetivos, intereses políticos y económicos, o en las afirmaciones de sus guías e informantes. Reconstruye un perfil de los viajeros que son citados con mayor frecuencia por los historiadores, sus apreciaciones sobre el paisaje sabanero y la actividad agrícola y ganadera y su influencia en las reconstrucciones que en la actualidad se hacen de la historia agraria de la Sabana de Bogotá durante el siglo XIX. Invita a contrastar los relatos de viajeros entre sí y con otras fuentes e ncorporar en los análisis los resultados de investigaciones sobre el periodo colonial y las condiciones biofísicas de las regiones objeto de estudio.

  1. Concentración de la propiedad de la tierra y producto agrícola en Antioquia. 1995-2004

    Directory of Open Access Journals (Sweden)

    Juan Carlos Muñoz

    2008-04-01

    Full Text Available El presente trabajo analiza la relación entre la concentración de la propiedad rural y el producto agrícola para el departamento de Antioquia y se plantea una metodología para la validación de esta relación a nivel estadístico. Además, se desarrolla una descripción por subregiones de la estructura productiva y de la propiedad rural y se hace una reflexión, a partir de la relación planteada, sobre las políticas adecuadas para promover en la región una estructura de propiedad equitativa. Se encontró que la situación de la producción agrícola es precaria, lo cual pone en peligro la sostenibilidad ambiental y productiva de la región y motiva niveles de desigualdad entre las subregiones. Este deterioro de la producción va aparejado a altos niveles de concentración de la propiedad, provocando con ello un deterioro de la mediana propiedad y el aumento de los minifundios.

  2. La investigación agrícola en América Latina y el Caribe desde una perspectiva bibliométrica

    Directory of Open Access Journals (Sweden)

    Miguel Arenas Vargas

    2004-01-01

    Full Text Available Es sabido que los países desarrollados realizan la mayor parte de la investigación agropecuaria, sin embargo, es necesario, identificar en qué grado se practica la investigación en los países de América Latina y El Caribe, motivo por el cual se emprendió un estudio bibliométrico que permitiera identificar sus fortalezas y debilidades. Se recurrió al Science Citation Index Expanded, periodo 1995-2002 y se obtuvieron los registros de artículos publicados en revistas indizadas en el men-cionado índice así como los artículos citados y las citas recibidas. Se utilizaron 6 categorías del Journal Citation Reports: Economía y Política Agrícola; Ingeniería Agrícola, Buiatría y Ciencia Animal; Agricultura (multidisciplinas; Ciencia del Suelo; y Agronomía. Se encontró que el mayor número de artículos correspondió a las revistas clasificadas en Buiatría y Ciencia Animal.

  3. El alojamiento previsto para temporeros gestionado por el sindicato agrícola Unió de Pagesos. Infraestructura para la disciplina y el suministro de trabajadores

    Directory of Open Access Journals (Sweden)

    Olga Achón Rodríguez

    2012-07-01

    Full Text Available El éxito de implantación del sistema de importación y suministro de trabajadores contratados en origen –implementado por el sindicato agrícola Unió de Pagesos- ha precisado la instauración de una red de alojamientos prevista a la concentración de mano de obra. Su descripción, y el establecimiento de tipologías, que sirven al análisis de estos lugares, se han realizado con el ánimo de mostrar una realidad velada por el discurso filantrópico del sindicato. Dispositivo de poder dispuesto a la doma del sujeto –merced la normativización del espacio y la presencia de personal encargado- por el mismo se pretende la creación de una corriente de fuerza de trabajo por la que la gestión fordiana de los hombres se efectúa. Su estudio manifiesta la tradicional forma de alojar al temporero agrícola, únicamente superada en cuanto configurado un nuevo estatuto jurídico, el del trabajador contratado en origen para la realización de faenas de recolección. 

  4. La organización de sindicatos de jornaleros agrícolas en el valle de Mexicali, 1920-1990

    Directory of Open Access Journals (Sweden)

    Leticia Figueroa Ramírez

    1992-01-01

    Full Text Available En este artículo se propone que la organización de sindicatos de jornaleros agrícolas en el valle de Mexicali entre 1920 y 1990, tuvo una relación directa con situaciones coyunturales y político-ideológicas, y no como producto de concentración de fuerza de trabajo o de crecimiento de la actividad agrícola. Para constatar lo anterior, el análisis se divide en tres periodos en los que se van señalando modificaciones tanto en la composición y número de la fuerza de trabajo como en relación con la tenencia de la tierra en el valle citado. Asimismo para cada uno de los periodos se realizó la búsqueda de las situaciones arriba mencionadas, que pudieron haber impulsado a los trabajadores a organizarse. Las fluctuaciones que manifiesta la organización durante el periodo que comprende el estudio se demuestran con referencias de fuentes históricas y con los registros de esas asociaciones provenientes de la Junta Local de Conciliación y Arbitraje de Mexicali

  5. Desarrollo de un proyecto agrícola en la región marginal de la Patagonia Meridional Argentina. El caso de Gobernador Gregores

    Directory of Open Access Journals (Sweden)

    María Eugenia Cepparo de Grosso

    2012-02-01

    Full Text Available Santa Cruz, provincia ubicada en el extremo sur del territorio continental argentino, posee un ambiente fuertemente condicionado por la fragilidad de sus características naturales y una situación socioeconómica tradicionalmente orientada a la monoactividad ganadera en el área rural y a los servicios públicos en los centros urbanos. En ese marco, y durante la década de 1990, surgió una iniciativa apoyada por organismos del Estado y financiada por bancos provinciales para estimular un proyecto agrícola adaptado a las limitadas aptitudes agrícolas de la región. Un reducido número de agricultores, inquietos por generar actividades que diversificaran el tradicional modelo pastoril, experimentaron los dilemas de los comienzos y las crisis de un proyecto de estímulo económico en un territorio marginal. Este trabajo contribuye con una serie de reflexiones acerca de las motivaciones que justifican el estudio de pequeñas sociedades en áreas marginales; de la confrontación entre el marco conceptual de la marginalidad según los países centrales y los periféricos; y del accionar y el compromiso de los actores sociales motivados por una alternativa de desarrollo local en una localidad ubicada en el centro de la Patagonia Meridional Argentina.

  6. Programa de Ingeniería Agrícola Bases para su Creación y Desarrollo Histórico

    Directory of Open Access Journals (Sweden)

    Bustamante B. Fabio

    1975-06-01

    Full Text Available La historia de la Faculta Nacional de Agronomía de la Universidad Nacional de Colombia en Medellín es rica en actividades y en cambios, todos estrechamente ligados con el desarrollo de la industria agropecuaria del país en sus diferentes campos. El dinamismo que ha mostrado durante más de cincuenta años de existencia le ha servido para ajustarse a los adelantos de la ciencia, con lo cual ha podido proyectarse eficazmente a la vida agrícola nacional por medio de sus diferentes programas. Dentro de este breve esbozo histórico no puede dejar de mencionar los nombres de varios meritorios profesores que han dictado cátedras relacionadas con la Ingeniería Agrícola en algunas de sus ��pocas, con cuyos valiosos conocimientos y visión del futuro contribuyeron a trazar el derrotero definitivo que ha servido para que, en el transcurso de 25 años, se conformara la ingeniería como una profesión fundamental para el progreso del país, dada su decidida contribución al aumento y mejoramiento de la producción del sector agropecuario.

  7. Seroprevalencia de brucelosis en trabajadores agrícolas de las comarcas costeras de Castellón, España

    Directory of Open Access Journals (Sweden)

    Villamarín-Vázquez José Luis

    2002-01-01

    Full Text Available Objetivo. Determinar la seroprevalencia de brucelosis en trabajadores agrícolas. Material y métodos. Estudio transversal efectuado durante 1996 y 1997 en la Unidad de Salud Laboral del Centro de Salud Pública (CSP de Castellón, España, con 482 aspirantes a su acreditación como manipulador de plaguicidas para aplicación agrícola y a quienes se les hicieron las pruebas serológicas de rosa de Bengala, seroaglutinación de Wright y Coombs antibrucela. En el análisis estadístico se estimó la prevalencia y se usó regresión logística. Resultados. 15 personas (3.1%, IC 95% 1.8%-5.1% presentaron títulos de 1/40 o mayores a las pruebas de Wright o Coombs, y todas negativas al rosa de Bengala. No se apreció riesgo profesional elevado. Conclusiones. La prevalencia estimada fue baja.

  8. Programa de Ingeniería Agrícola en la Facultad de Agronomía de Medellín

    Directory of Open Access Journals (Sweden)

    Gómez Jorge Mario

    1975-06-01

    Full Text Available El Ingeniero Agrícola nació respuesta a una doble necesidad:  1.       En el abanico de las profesiones agropecuarias, de la necesidad de un profesional con una mentalidad diferente. Con un énfasis en ciencias físicas y matemáticas, exigidas por áreas que tradicionalmente venían cubriendo en forma deficiente otras profesiones, y que le permitieran además, cubrir otras áreas que exigían igualmente dicha preparación. 2.       En el aspecto de las ingenierías como la necesidad de un profesional  con un conocimiento de las limitaciones y características especiales de la cuantificación biológica. En consecuencia el programa curricular de la carrera Ingeniería Agrícola, tiende a dar respuesta a la necesidad de un profesional que contribuya al desarrollo racional del país, en lo relacionado con la aplicación de las ciencias físicas, matemáticas, biológicas y de ingeniería para el aumento y conservación del potencial de la tierra, el aumento de la productividad de la tierra, el trabajo y la industrialización agropecuaria.

  9. Acceptance Test Data for Candidate AGR-5/6/7 TRISO Particle Batches BWXT Coater Batches 93165 93172 Defective IPyC Fraction and Pyrocarbon Anisotropy

    Energy Technology Data Exchange (ETDEWEB)

    Helmreich, Grant W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Hunn, John D. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Skitt, Darren J. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dyer, John A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Schumacher, Austin T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-03-01

    Coated particle fuel batches J52O-16-93165, 93166, 93168, 93169, 93170, and 93172 were produced by Babcock and Wilcox Technologies (BWXT) for possible selection as fuel for the Advanced Gas Reactor Fuel Development and Qualification (AGR) Program’s AGR-5/6/7 irradiation test in the Idaho National Laboratory (INL) Advanced Test Reactor (ATR). Some of these batches may alternately be used as demonstration coated particle fuel for other experiments. Each batch was coated in a 150-mm-diameter production-scale fluidized-bed chemical vapor deposition (CVD) furnace. Tristructural isotropic (TRISO) coatings were deposited on 425-μm-nominal-diameter spherical kernels from BWXT lot J52R-16-69317 containing a mixture of 15.5%-enriched uranium carbide and uranium oxide (UCO). The TRISO coatings consisted of four consecutive CVD layers: a ~50% dense carbon buffer layer with 100-μm-nominal thickness, a dense inner pyrolytic carbon (IPyC) layer with 40-μm-nominal thickness, a silicon carbide (SiC) layer with 35-μm-nominal thickness, and a dense outer pyrolytic carbon (OPyC) layer with 40-μmnominal thickness. The TRISO-coated particle batches were sieved to upgrade the particles by removing over-sized and under-sized material, and the upgraded batches were designated by appending the letter A to the end of the batch number (e.g., 93165A).

  10. Incentivos a la innovación de la biotecnología agrícola-alimentaria en México

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    Marcela Amaro-Rosales

    2015-01-01

    Full Text Available En el artículo analizamos la innovación biotecnológica relacionada con los sectores agrícola y alimentario en México. Tomamos en cuenta las políticas públicas, las leyes y las reglamentaciones; la dinámica del sector y del merado. Asimismo, analizamos la forma en la que las empresas agro-alimentarias pueden aprovechar los insumos de conocimiento científico y tecnológico que ofrece la biotecnología. La principal conclusión es que actualmente el marco institucional regulatorio y la dinámica del mercado establecen más barreras que incentivos para el desarrollo y aplicación de innovaciones biotecnológicas y con ello lograr una mejora en la cali - dad de los alimentos y un incremento en la competitividad de las empresas y del sector agrícola en el país.

  11. Efectos del tlcan sobre el empleo de mano de obra en el sector agrícola de México, 1994-2010

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    Yuliana Lechuga Jardínez

    2014-01-01

    Full Text Available el Tratado de Libre Comercio de América del Norte se implementó en 1994 para solucionar el desempleo de mano de obra en el campo mexicano, sin embargo, actual - mente las zonas rurales del país enfrentan el mismo pro - blema. Se calcularon las fuentes de crecimiento del em - pleo de mano de obra, de 1994 a 2010, con la finalidad de determinar su impacto sobre el sector agrícola de Méxi - co. Los resultados indican que el cambio en la estructura productiva fue desfavorable para el empleo en general, no obstante, el agrícola creció en diez millones de jornadas debido a un incremento en la superficie cosechada y a un aumento en los requerimientos de mano de obra. En Sinaloa, el cambio en la estructura productiva y una ma - yor mecanización perjudicaron al empleo, a diferencia de lo ocurrido en Estado de México y Chiapas, en donde lo beneficiaron.

  12. ExploMaq, software para la evaluación energética y económica de la maquinaria agrícola

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    Carlos A. Pereira Marín

    2015-01-01

    Full Text Available El presente trabajo se realizó con el objetivo de desarrollar un software para viabilizar la evaluación energética y económica del conjunto tractor-implemento, con un diseño de aplicación sobre ventanas y sistema portable. El software ExploMaq, determina la evaluación energética del conjunto tractor-máquina agrícola a partir del cálculo de las fuerzas que actúan en una única labor, también evalúa el balance de potencia, calculado a partir de las pérdidas de diferentes tipos de potencia y otros factores de resistencia. Es posible además, la evaluación de los gastos directos de explotación. El software, en su primera versión de prueba y puesta a punto, está a disposición de usuarios con objetivos académicos e investigativos sobre la evaluación energética de máquinas agrícolas.

  13. Estatuto da Terra: debates políticos e as disputas pela forma da reforma agrária no primeiro governo militar

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    Carmem Lúcia Gomes De Salis

    2014-07-01

    Full Text Available Em plena vigência da ditadura, em 30 de novembro de 1964, foi promulgado pelo governo militar de Humberto Alencar Castello Branco, o Estatuto da Terra, caracterizado enquanto um conjunto de dispositivos legais que definiam, entre outros fatores, o que era propriedade da terra no Brasil, bem como, os instrumentos necessários para se realizar a Reforma Agrária. Embora tenha sido aprovado pelo Congresso ainda no primeiro ano do governo, seu processo de elaboração e tramitação constituiu-se em um período de intensas discussões políticas acerca do alcance e da natureza que esta proposta deveria assumir.  Neste sentido, o presente artigo objetiva compreender as disputas políticas que ocorreram, mesmo sobre o regime de exceção, pela forma da Reforma Agrária. Para essa análise utilizamos, especialmente os discursos parlamentares proferidos nos meses que antecederam a aprovação da lei e as colunas publicadas na grande imprensa, pois essas fontes possibilitam refletir sobre os posicionamentos de diversos agentes envolvidos, como: políticos, associações patronais e o governo.

  14. A Lei de Sementes brasileira e os seus impactos sobre a agrobiodiversidade e os sistemas agrícolas locais e tradicionais

    Directory of Open Access Journals (Sweden)

    Juliana Santilli

    Full Text Available O artigo faz uma análise crítica dos impactos da Lei de Sementes brasileira (10.711/2003 sobre a biodiversidade agrícola e sobre a agricultura tradicional e local. A referida lei atende, principalmente, aos interesses e necessidades do sistema 'formal' de sementes e desconsidera o importante papel dos sistemas de sementes locais e tradicionais (chamados frequentemente de 'informais', nos quais as atividades de produção, intercâmbio, melhoramento e conservação de sementes são realizadas pelos próprios agricultores por meio de suas redes sociais e segundo as normas locais. Os sistemas 'formais' de sementes estão voltados, principalmente, para as espécies agrícolas de grande valor comercial e de ampla utilização em ambientes homogêneos. Assim, não são capazes de oferecer sementes adaptadas a usos e condições locais específicas e de atender às necessidades dos agricultores tradicionais e locais, que dispõem de poucos recursos e vivem em regiões heterogêneas, ambiental e culturalmente.

  15. Análisis de neumático por elementos finitos con vistas a la determinación de coeficientes de cargas dinámicas en estructuras de máquinas agrícolas

    OpenAIRE

    Raudel Flores Moreno; Arturo Martínez Rodríguez; Gelasio Valerio Pacheco Sánchez; Vladimir Lenin Reyes de la Cruz; Alberto Iraldo Dávila García

    2010-01-01

    Las complejidades asociadas al cálculo con exactitud de coeficientes de cargas dinámicas en estructuras de máquinas agrícolas sometidas a cargas de impacto, traen aparejadas otras dificultades relacionadas con el sobredimensionado de las piezas, lo cual da lugar a exceso de peso y gastos adicionales. En el caso de las máquinas agrícolas es de vital importancia el estudio de los sistemas de amortiguación, ya que éstos son capaces de absorber parte de las cargas de impacto disminuyendo las afec...

  16. Evaluación de la capacidad productiva de Pleurotus ostreatus con el uso de hoja de plátano (Musa paradisiaca l., cv . roatan) deshidratada, en relación con otros sustratos agrícolas

    OpenAIRE

    Romero, Omar; Huerta, Manuel; Damián Huato, Miguel Angel; Macías, Antonio; Tapia, Ana María; Parraguirre Lezama, José F.C.; Juárez, Jaime

    2010-01-01

    El objetivo de este estudio fue evaluar la producción de la cepa CP-50 de P. ostreatus en residuos de hoja de plátano deshidratada en contraste con otros sustratos agrícolas de desecho del Municipio de Tetela de Ocampo-Puebla. Las hojas de plátano (M. paradisiaca) fueron colectadas en la zona de Martínez de la Torre, Veracruz- México y los demás sustratos agrícolas como paja de trigo (T. aestivum), paja de cebada (H. vulgare), pajilla de frijol (P. vulgaris) y rastrojo de maíz (Z. mays) se ad...

  17. Evaluación de la capacidad productiva de Pleurotus ostreatus utilizando hoja de plátano deshidratada (Musa paradisiaca L.), en relación con otros sustratos agrícolas

    OpenAIRE

    Omar Romero; Manuel Huerta; Miguel Angel Damián; Antonio Macías; Ana María Tapia; José F.C. Parraguirre; Jaime Juárez

    2010-01-01

    El objetivo de este estudio fue evaluar la producción de la cepa CP-50 de P. ostreatus en residuos de hoja de plátano deshidratada en contraste con otros sustratos agrícolas de desecho del Municipio de Tetela de Ocampo-Puebla. Las hojas de plátano (M. paradisiaca) fueron colectadas en la zona de Martínez de la Torre, Veracruz- México y los demás sustratos agrícolas como paja de trigo (T. aestivum), paja de cebada (H. vulgare), pajilla de frijol (P. vulgaris) y rastrojo de maíz (Z. mays) se ad...

  18. Desenvolvimento do coeficiente parcial de ergonomia e segurança em tratores agrícolas Development of partial ergonomic and safety coefficient of agricultural tractors

    Directory of Open Access Journals (Sweden)

    Henrique Debiasi

    2004-12-01

    Full Text Available O presente trabalho teve como objetivo criar e aplicar o coeficiente parcial de ergonomia e segurança em tratores agrícolas (COPES. O COPES corresponde a um valor numérico variável de 0 a 100, que expressa a qualidade em termos de ergonomia e segurança dos tratores agrícolas. O referido coeficiente foi desenvolvido e avaliado por meio da verificação da presença e estado de conservação de itens relacionados à ergonomia e segurança, em 175 tratores agrícolas usados, presentes em 114 propriedades amostradas junto às microrregiões gaúchas de Santa Maria, Restinga Seca e Cachoeira do Sul. Os resultados mostraram que o COPES apresentou grande variação entre os tratores amostrados (7,64 a 84,80, sendo a média geral inferior a 35. Isso demonstra que os tratores agrícolas, atualmente em uso na região abrangida por esta pesquisa, se caracterizam por más condições relacionadas à ergonomia e segurança. Além disso, o valor do COPES mostrou que diminui em escala logarítmica conforme aumenta o tempo de uso dos tratores (r² = 0,8018. Assim, pode-se concluir que o COPES é uma importante ferramenta para a avaliação quantitativa das condições de ergonomia e segurança em tratores agrícolas, demonstrando sensibilidade às variações apresentadas no que se refere a essas características.The objective of this work was to create and apply the partial ergonomic and safety coefficient of agricultural tractors (COPES. The COPES is a numeric value variable from 0 to 100, showing ergonomic and safety conditions of agricultural tractors. This coefficient was developed and tested through checking the presence and conservation condition of ergonomic and safety items in 175 used agricultural tractors belonging to 114 farms localized in the regions of Santa Maria, Restinga Seca and Cachoeira do Sul, Brazil. The results showed that the COPES presented a considerable variation between the agricultural tractors sampled (7.64 to 84.80. The

  19. Políticas trabalhista, fundiária e de crédito agrícola no Brasil

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    Gervásio Castro de Rezende

    2006-03-01

    Full Text Available Este artigo discute as causas do padrão concentrador do desenvolvimento agrícola brasileiro recente, expresso no predomínio da produção em grande escala, elevado índice de mecanização e baixa absorção de mão de obra não qualificada. Cita, inicialmente, a existência de duas posições antagônicas que procuram explicar esse fato: uma, que culpa a herança latifundiária de nossa agricultura, e a outra, que vê nisso um determinismo tecnológico, não havendo, assim, possibilidade de atuar sobre esse problema sem incorrer numa perda em termos de eficiência econômica. Este trabalho, contudo, atribui às políticas trabalhista agrícola, fundiária e de crédito agrícola, instituídas na década de 1960, a responsabilidade maior por esse problema. Conforme a análise apresentada, essas políticas inviabilizaram o mercado de trabalho agrícola temporário e a agricultura familiar, ao mesmo tempo em que fomentaram a mecanização agrícola e o predomínio da produção em grande escala. O trabalho termina propondo uma desregulamentação dos mercados de trabalho e de terra na agricultura brasileira, assim como uma redução drástica do subsídio ao crédito rural.This paper discusses the question of the concentrated pattern of agricultural development in Brazil, as expressed in the predominance of large-scale production, high level of mechanization and low absorption of non-qualified labor. It is proposed, initially, the existence of two conflicting explanations for this fact: the first, that blames our historical heritage, characterized by the predominance of the latifundio, and the second, that sees in this fact a technological determinism, with the implication that lesser concentration in agriculture would involve a loss of economic efficiency. This paper, however, attributes to the labor, land and credit policies directed to agriculture, instituted in the decade of 1960, the major responsibility for this problem. As the analysis

  20. Efecto ambiental de agroquímicos y maquinaria agrícola en cultivos transgénicos y convencionales de algodón

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    Giovanni Reyes

    2010-10-01

    Full Text Available Título en inglés: Environmental effects of agrochemicals and agricultural machinery in transgenic and conventional crops cotton Resumen La producción de alimentos se basa en el uso de diferentes tecnologías agrícolas, que pueden derivar en conflictos entre medioambiente y agricultura. Es significativo estudiar el impacto ambiental de las nuevas tecnologías aplicadas a la agricultura, la más importante de las cuales es la transgénesis. Este trabajo se realizó en la zona algodonera del municipio del Espinal, departamento del Tolima, para la cosecha de algodón del primer semestre de 2009, usando las metodologías de Brookes y Barfoot (2006 y Kovach y colaboradores (1992. Se estudió el efecto ambiental de la aplicación de agroquímicos y el uso de maquinaria agrícola en cultivos de algodón transgénico y convencional. Se recogió información mediante encuestas en veinte fincas productoras de algodón. El análisis de las encuestas se realizó de forma descriptiva, determinando diferencias de tipo cuantitativo y cualitativo para los predios que utilizan la tecnología convencional o la tecnología transgénicas (doble gen, Bt/RR, para luego realizar una correlación con el “Enviromental Index Quotient” (EIQ. No se encontraron diferencias entre el EIQ de campo de las dos tecnologías, aunque la tecnología transgénica tiene ventajas ambientales en el control de algunas plagas de lepidópteros. En relación con el uso de maquinaria agrícola, se encontró que la tecnología convencional genera menor liberación de CO2, gas de efecto invernadero. La metodología de Brookes y Barfoot puede adaptarse para estudios comparativos de tecnologías agrícolas en países tropicales. Palabras clave: algodón; cultivos transgénicos; efectos ambientales; maquinaria agrícola; emisiones CO2; EIQ. Abstract Food production is based on the use of various agricultural technologies, which can lead to conflicts between environment and agriculture. It

  1. Agricultural Labor Demand in Chile: A Cointegration Approach Demanda por Trabajo Agrícola en Chile: Un Enfoque de Cointegración

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    Rodrigo Saens N

    2008-12-01

    Full Text Available International evidence shows that the positive relationship between product and agricultural labor has weakened during the last 30 years, especially in emergent economies. Chilean agriculture has not been left out of this phenomenon The main purpose of this reseach was to estimate the causality relationships that govern the product, employment and salaries in the Chilean silviculture-agricultural-livestock sector, using a cointegration approach. Quarterly data from the 1996-2005 period were employed to estimate agricultural labor demand. A Cobb-Douglas agricultural production function was employed and from it were derived the minimum cost function and the labor demand as bases of this study; the latter was approximated log-linearly to find different measures of elasticity. The main results shows that the estimated demand for agricultural labor has long-run employment-product and employment-salary elasticities of 0.38 and -0.88, respectively. An important conclusion suggests that, compared with the employment-product and employment-salary elasticities of labor demand on the aggregated level, agricultural employment in the long run results less sensitive to changes in the product, but more sensitive to changes in salaries.La evidencia internacional muestra que la relación positiva entre producto y empleo agrícola se ha debilitado en los últimos 30 años, especialmente en economías emergentes. La agricultura en Chile no ha estado al margen de este fenómeno. El objetivo principal de esta investigación fue estimar las relaciones de causalidad que rigen al producto, el empleo y los salarios en el sector silvoagropecuario chileno, utilizando un enfoque de cointegración. Para la estimación de la demanda por trabajo agrícola se utilizaron datos trimestrales del período 1996 a 2005. Se utilizó una función de producción agrícola tipo Cobb-Douglas, a partir de la cual se derivó la función de costo mínimo y la demanda por trabajo base de

  2. Capítulo 4. Investigaciones que Deben Iniciarse en Colombia en Economía de Producción Agrícola

    Directory of Open Access Journals (Sweden)

    Beltrán G. Gregorio

    1953-09-01

    Full Text Available Podría decirse, sin temor a pecar de exagerados, que en Colombia todo está por hacer en cuestiones de economía agrícola. Esto, como es natural, nos plantea un problema económico básico: Decidir qué estudios deben iniciarse primero, a fin de obtener una mejor utilización de nuestros limitados recursos. En nuestra opinión los estudios que tienen más importancia son aquellos de tipo básico que nos pueden dar la información necesaria para continuar de una manera progresiva las investigaciones en ciencias sociales. Dadas las condiciones del país, creemos que los tres tipos de estudios básicos más urgentes son los de: Geografía Económica, Sociología Rural y Estadística Agrícola. Geografía económica: En realidad se desconoce al país; sólo tenemos una idea aproximada de lo que son las distintas regiones naturales, pero no sabemos nada acerca de sus interrelaciones económicas. La prueba más diciente de que en Colombia los estudios de geografía económica están atrasados, es que en el país no existe todavía una Facultad de Geografía dependiente de ninguna Universidad. Y los pocos estudios iniciados, al igual que los reconocimientos de suelos, han marchado con un paso extremadamente lento, y muchos de ellos se han basado en datos fundamentalmente errados. Es por esto por lo que se necesitan estudios básicos de geografía económica en el país a fin de acabar con una serie de conceptos falsos y poder así iniciar estudios verdaderamente científicos. Sociología Rural: No solo deben hacerse estudios de geografía económica sino también estudios de sociología rural. Es decir, debe estudiarse la ecología social o geografía humana, que según la define Taylor es: El estudio de las maneras como los pueblos se distribuyen por sí mismos sobre la tierra al desarrollar y utilizar los recursos naturales en respuesta a las fuerzas culturales y sociales. Va más allá que la geografía o económica y es más importante que

  3. Software para estimativa do custo operacional de máquinas agrícolas - MAQCONTROL Development of software to compute operational costs of farm machinery - MAQCONTROL

    Directory of Open Access Journals (Sweden)

    Liane Piacentini

    2012-06-01

    Full Text Available A seleção e a otimização de sistemas mecanizados são os principais objetivos da mecanização racional. Não é suficiente uma compra adequada do maquinário agrícola se sua utilização não for controlada em aspectos operacionais e financeiros. Neste trabalho, é descrito o desenvolvimento de software para estimativa do custo operacional de máquinas agrícolas (MAQCONTROL, utilizando o ambiente de desenvolvimento Borland Delphi e o banco de dados Firebird. Os custos operacionais foram divididos em fixos e variáveis. Nos custos fixos, foram estimadas as despesas com depreciação, juros, alojamento e seguros. Nos custos variáveis, foi dada ênfase aos custos de manutenção como: óleos lubrificantes, filtros, pneus, graxa, combustível, pequenos reparos e troca de peças. Os resultados demonstraram a eficiência do software para os objetivos propostos. Assim, o MAQCONTROL pode ser uma importante ferramenta no processo de administração rural, pois reduz os custos da informação e agiliza a determinação precisa dos custos operacionais de máquinas agrícolas.The rational mechanization has as main objectives the selection and optimization of mechanized systems. An adequate purchase of agricultural machinery is not sufficient if its use is not controlled in operational and financial aspects. This work describes the development of software to estimate operational costs of agricultural machinery (MAQCONTROL, using Borland Delphi's development environment and Firebird database. The operational costs were divided in fixed and variable. In fixed costs, the expenses with depreciation, interest, storage and insurance were estimated. In variable costs, the emphasis was given to the expenses on maintenance, lubricating oils, filters, tires, grease, fuel, small repairs, and parts replacement. Results have shown the software efficiency for the proposed objectives. Therefore, the MAQCONTROL software proved to be an important tool in the rural

  4. Indicadores para estimar la sostenibilidad agrícola de la cuenca media del río Reventado, Cartago, Costa Rica

    Directory of Open Access Journals (Sweden)

    Laura Ram\\u00EDrez

    2008-01-01

    Full Text Available El objetivo de este trabajo fue identificar indicadores para evaluar la sostenibilidad agrícola en la cuenca media del río Reventado. Se encontró una acumulación Ca, Mg y K en los terrenos y una disminución del porcentaje de saturación de acidez con los años de uso del suelo en agricultura, los suelos han mejorado su fertilidad con el tiempo por efecto antrópico. Se encontró una tendencia similar con el P disponible, cuyos niveles aumentaron en ≈2,3 mg.l-1.año-1, eventualmente podría reducirse la aplicación de este elemento, lo que haría más sostenible el sistema de producción. Los niveles de erosión, en la mayoría de las fincas, fueron moderados; el grosor del horizonte A y el P disponible disminuyeron al pasar de erosión leve, a moderada y a severa. El índice estructural y la capacidad de uso de las tierras indicaron en las Clases II y III, suelos moderadamente susceptibles a ser degradados, y en las clases mayores alta susceptibilidad a ser degradados. No se encontró diferencias significativas entre las clases de capacidad de uso de la tierra y la producción de los cultivos. La producción de papa y cebolla fue mayor en zonas con riego, donde la relación B/C mayor se encontró en Tierra Blanca, debido al manejo del sistema productivo. Los indicadores económicos y sociales evaluados fueron positivos para ambas regiones, no así los indicadores ambientales. La actividad agrícola aún se mantiene como una actividad rentable para los productores de la cuenca media del río Reventadoactividad agrícola aún se mantiene como una actividad rentable para los productores de la cuenca media del río Reventado

  5. Molecular characteristics of methicillin-resistant Staphylococcus aureus (MRSA) strains isolated from patients with bacteremia based on MLST, SCCmec, spa, and agr locus types analysis.

    Science.gov (United States)

    Goudarzi, Mehdi; Seyedjavadi, Sima Sadat; Nasiri, Mohammad Javad; Goudarzi, Hossein; Sajadi Nia, Raheleh; Dabiri, Hossein

    2017-03-01

    The widespread emergence of methicillin resistant Staphylococcus aureus, as a common cause of nosocomial infections, is becoming a serious concern in global public health. The objective of the present study was to investigate antimicrobial susceptibility pattern, frequency of virulence genes and molecular characteristics of methicillin-resistant Staphylococcus aureus strains isolated from patients with bacteremia. A total of 128 methicillin-resistant Staphylococcus aureus isolates were collected during February 2015 to January 2016. In vitro antimicrobial susceptibility of the isolates was assessed using the disk diffusion method. Conventional PCR was performed for the detection of adhesion (can, bbp, ebp, fnbB, fnbA, clfB, clfA) and toxin (etb, eta, pvl, tst) encoding genes, determining the agr type, SCCmec, MLST and spa typing of the isolates. All the methicillin-resistant Staphylococcus aureus isolates were found to be sensitive to linezolid, teicoplanin, and vancomycin. Resistance to the tested antibiotics varied from 97.7% for penicillin to 24.2% for mupirocin. The rate of multi drug resistance (MDR) in the present study was 97.7%. The most commonly detected toxin and adhesion genes were tst (58.6%), and clfB (100%), respectively. The majority of SCCmec III isolates were found in agr group I while SCCmec IV and II isolates were distributed among agr group III. Multilocus Sequence Typing (MLST) of the MRSA isolates showed five different sequence types: ST239 (43%), ST22 (39.8%), ST585 (10.9%), ST45 (3.9%) and ST240 (2.3%). All of the pvl positive strains belonged to ST22-SCCmec IV/t790 clone and were MDR. Among different 7 spa types, the most common were t790 (27.3%), t037 (21.9%), and t030 (14.1%). spa types t016, t924 and spa type t383 were reported for the first time from Asia and Iran, respectively. It was shown that spa types circulating in the studied hospitals varied which support the need to perform future surveillance studies in order to understand

  6. Calidad de Andosols en sistemas forestal, agroforestal y agrícola con diferentes manejos en Zacatlán, Puebla

    Directory of Open Access Journals (Sweden)

    Jonathan Omar Hernández Ordoñez

    2017-04-01

    Full Text Available Los estudios de suelos en sistemas agroforestales relacionados con bosques mesófilos de montaña han sido poco abordados en nuestro país, especialmente los desarrollados en Andosols, los cuales son susceptibles a los procesos de degradación por el cambio de uso del suelo. El presente estudio se realizó en el municipio de Zacatlán, Puebla con el objetivo de caracterizar la calidad de los Andosols bajo diferentes sistemas de manejo. Los métodos que se emplearon fueron: entrevistas a productores para identificar los sistemas, descripción de perfiles de suelos, análisis de laboratorio y análisis de similaridad de los diferentes manejos. Los resultados indicaron que la zona de estudio está integrada por tres sistemas: bosque mesófilo de Montaña (BMM, agroforestal (asociaciones manzana-maíz-calabaza-arándanos y agrícola, con adición de abonos orgánicos (FO o fertilización inorgánica (FI. En los Andosols con BMM, la estructura biológica domina (agregados migajosos y granulares hasta los 55 cm de profundidad, presentan alto contenido de materia orgánica del suelo (MOS (31%, alta retención de humedad (194.5% y baja densidad aparente (Da (0.49 g cm-3. Con el cambio de uso de suelo (de bosque a agroforestal o agrícola, la estructura biológica se reduce en espesor o desaparece y dominan los bloques sub-angulares, debido a la disminución drástica del contenido de MOS (a 16.3 o a 6.3%, y retención de humedad (de 97 o a 47%. Además, la Da aumentó hasta 1 g cm-3 en el sistema agrícola. Por el contrario, en tierras degradadas, el sistema agroforestal con manejo orgánico ha mejorado la calidad del horizonte superficial en menos de seis años y con la FO o FI algunos sistemas agroforestales aumentaron los contenidos de Ntot y P. Los índices que mejor caracterizaron la calidad de los Andosols bajo diferentes sistemas fueron: estructura del suelo, MOS, Ntot, P y retención de humedad.

  7. Impact of the regulatory loci agr, sarA and sae of Staphylococcus aureus on the induction of alpha-toxin during device-related infection resolved by direct quantitative transcript analysis.

    Science.gov (United States)

    Goerke, C; Fluckiger, U; Steinhuber, A; Zimmerli, W; Wolz, C

    2001-06-01

    The cytotoxic alpha-toxin (encoded by hla) of Staphylococcus aureus is regulated by three loci, agr, sarA and sae, in vitro. Here, we assess the regulation of hla in a guinea pig model of device-related infection by quantifying RNAIII (the effector molecule of agr) and hla directly in exudates accumulating in infected devices without subculturing of the bacteria. LightCycler reverse transcription-polymerase chain reaction (RT-PCR) was used to quantify the transcripts. Strains RN6390 and Newman expressed considerably smaller amounts of RNAIII in the guinea pig than during in vitro growth. The residual RNAIII expression decreased during the course of infection and was negatively correlated with bacterial densities. As with RNAIII, the highest hla expression was detected in both strains early in infection. Even in strain Newman, a weak hla producer in vitro, a pronounced expression of hla was observed during infection. Likewise, four S. aureus isolates from cystic fibrosis (CF) patients expressed Q1hla despite an inactive agr during device-related infection as in the CF lung. Mutation of agr and sarA in strain Newman and RN6390 had no consequence for hla expression in vivo. In contrast, the mutation in sae resulted in severe downregulation of hla in vitro as well as in vivo. In conclusion, S. aureus seems to be provided with regulatory circuits different from those characterized in vitro to ensure alpha-toxin synthesis during infections.

  8. Marketing in the pre-development process of agricultural machines: a reference model Marketing no pré-desenvolvimento de máquinas agrícolas: um modelo de referência

    Directory of Open Access Journals (Sweden)

    Alexandre S. de Oliveira

    2012-08-01

    Full Text Available The theme of the research is the development of the domain of marketing knowledge in the design of agricultural machinery. It is developed throughout the design of agricultural machinery in order to identify the corporate and customers needs and to develop strategies to satisfy these needs. The central problem of the research questions which marketing tools to apply on pre-development process of farm machinery, in order to increase the market value of the products and of the company and, consequently, generate competitive advantage to the manufacturers of agricultural machinery. As methodology, it was developed bibliographical research and multicase study of the development process of agricultural machinery developed by small, medium and large companies and the academy. As a result, a marketing reference model was elaborated for the pre-development stage of agricultural machinery, which outlines the activities, tasks, mechanisms and controls that can be used in strategic planning and in products planning of agricultural machinery manufacturers, contributing to explain the explicit knowledge in the marketing field.O tema de pesquisa é o desenvolvimento do domínio de conhecimento de marketing no projeto de máquinas agrícolas. Este é desenvolvido ao longo do projeto de máquinas agrícolas a fim de identificar as necessidades dos clientes e da corporação e criar estratégias para que sejam satisfeitas. O problema central de pesquisa questiona quais mecanismos de marketing utilizar no processo de pré-desenvolvimento de máquinas agrícolas, para aumentar o valor de mercado dos produtos e da empresa e, conseqüentemente, gerar um diferencial competitivo às fabricantes de máquinas agrícolas. Como metodologia desenvolveu-se pesquisas bibliográficas e estudo de multicasos do processo de desenvolvimento de máquinas agrícolas desenvolvido pelas pequenas, médias e grandes empresas e pela academia. Como resultado elaborou-se um modelo

  9. Riesgo de precio en commodities : ¿profundización en la sensibilidad de precios agrícolas ante shocks de tasa de interés?

    Directory of Open Access Journals (Sweden)

    Gonzalo Rondinone

    2016-01-01

    Full Text Available El objetivo de este trabajo es someter a prueba el nivel de sensibilidad del precio de commodities agrícolas frente a shocks en la tasa de interés. El estudio se centrará específicamente en el caso del poroto de soja y del maíz, y mediante un sistema de vectores autorregresivos se evaluará la reacción de los precios ante alteraciones en la tasa de interés. En función de los resultados alcanzados, se esbozan algunas implicaciones que puede tener el proceso, sobre todo en relación con el impacto en países dependientes de la exportación de materias primas.

  10. Metodología para determinar la fuerza de arrastre de productos agrícolas a partir de la Dinámica de Fluidos Computacional (CFD)

    OpenAIRE

    2014-01-01

    El objetivo del trabajo consiste en obtener una metodología para la determinación, con el apoyo de herramientas de la Dinámica de Fluidos Computacional (CFD), de la fuerza de arrastre en productos agrícolas u otro tipo de sólido sometidos a una corriente de aire. Co- nociendo la distribución de presiones en la superficie y las coordenadas de posición de los nodos de la malla de elementos finitos generada, se elabora una metodología matemática, sobre la base de la geometría analítica y vectori...

  11. Priorización de factores críticos para implantar buenas prácticas agrícolas en pequeños productores

    OpenAIRE

    Gutiérrez-Guzmán, Nelson; Serra-B, Juan Antonio; Dussan-Sarria, Saúl

    2013-01-01

    Este artículo presenta la jerarquización de los factores y subfactores críticos que afectan la implantación de un programa de buenas prácticas agrícolas (BPA) para pequeños productores de café y frutas que realizan su labor productiva en el departamento del Huila en Colombia; se utilizó la metodología del Proceso Analítico Jerárquico con dos grupos decisores; se encontró que la mayor barrera para implantar un programa de BPA es la necesidad de inversión en infraestructura con una importancia ...

  12. La Ingeniería Agrícola: profesión básica en el desarrollo agroindustrial del país

    Directory of Open Access Journals (Sweden)

    Julio E. Ospina M.

    2011-02-01

    Full Text Available Se presentan aspectos fundamentales de una carrera que ha logrado alcanzar posición destacada no solo dentro de las profesiones del sector agropecuario, sino de otras afines o similares en su plan curricular. Dentro de este contexto se presentan las características generales de la profesión, historia y desarrollo que ha tenido en el ámbito colombiano y latinoamericano, las normas que le han dado la estructuración jurídica y académica dentro de la Universidad Nacional. Igualmente se presenta una serie de trabajos de investigación realizados en los diferentes campos de acción de la Ingeniería Agrícola, por los profesionales adscritos al cuerpo docente del Departamento, como un aporte al desarrollo del sector primario de la economía nacional.

  13. Xi congreso nacional de ingeniería agrícola y áreas afines- resúmenes de presentaciones orales y pósters

    OpenAIRE

    Facultad Nacional de Agronomía, Universidad Nacional de Colombia

    2013-01-01

    En este artículo tenemos los resúmenes de las presentaciones orales y posters del XI Congreso Nacional de Ingeniería Agrícola y Áreas Afines donde se pueden encontrar estos artículos:Dispositivo de bajo costo para la medición de la velocidad del viento.Diseño construcción y calibración de un pluviómetro de cazoletas de bajo costo usando interruptores magnéticos. Diseño, construcción y calibración de un lisímetro usando el efecto moiré.Dispositivo de bajo costo para la medición de radiación.De...

  14. Nivel de adecuación del territorio para el desarrollo de especies agrícolas y forestales en el Parque Nacional Nevado de Toluca

    Directory of Open Access Journals (Sweden)

    HÉCTOR HUGO REGIL-GARCÍA

    2009-01-01

    Full Text Available El Parque Nacional Nevado de Toluca es una importante reserva de recursos naturales del Estado de México. En la recuperación de los ecosistemas forestales se planteó como objetivo determinar el grado de adecuación para el desarrollo de especies forestales nativas y cultivos en la zona. En este trabajo se presenta una metodología basada en la aplicación de sistemas de información geográfica (SIG para evaluar algunos requerimientos de las especies (climáticos, fisiográficos y edáficos y generar mapas criterios de adecuación. El análisis permitió obtener la ocupación óptima del suelo de cuatro especies forestales y dos especies agrícolas.

  15. Xi congreso nacional de ingeniería agrícola y áreas afines- resúmenes de presentaciones orales y pósters

    OpenAIRE

    Facultad Nacional de Agronomía, Universidad Nacional de Colombia

    2013-01-01

    En este artículo tenemos los resúmenes de las presentaciones orales y posters del XI Congreso Nacional de Ingeniería Agrícola y Áreas Afines donde se pueden encontrar estos artículos:Dispositivo de bajo costo para la medición de la velocidad del viento.Diseño construcción y calibración de un pluviómetro de cazoletas de bajo costo usando interruptores magnéticos. Diseño, construcción y calibración de un lisímetro usando el efecto moiré.Dispositivo de bajo costo para la medición de radiación.De...

  16. Eiropas Savienības agrārpolitikas ietekme uz lauku ainavas attīstību paugurotā reljefā

    OpenAIRE

    Rasiņa, Kristīne

    2011-01-01

    Eiropas Savienības (ES) dalībvalstīs liela nozīme ir ES Kopējai lauksaimniecības politikai (KLP), kas ietekmē gan tautsaimniecības attīstību, gan arī zemes izmantošanu un lauku ainavu. Pēc 2013.gada ir paredzēta KLP reforma, kas mainīs atbalsta saņemšanas kritērijus, tāpēc pētījuma mērķis bija noskaidrot ES agrārpolitikas nozīmi lauku ainavas attīstībā Taurenes pagastā. Pētījuma ietvaros tika veikts Taurenes pagasta lauksaimniecības zemju apsekojums, VPM un MLA atbalsta telpiskā sadalījuma a...

  17. Repercusiones en la cubierta vegetal de la política de colonización agrícola en la Sierra de Salinas (Alicante)

    OpenAIRE

    Padilla Blanco, Asunción

    2000-01-01

    La política de colonización agrícola plasmada en la ley de Colonización y Repoblación Interior (1907) supuso una nueva organización del espacio en varios puntos del territorio español. Dentro de la provincia de Alicante, uno de los ejemplos aún vigentes es el de la Sierra de Salinas (Villena). La aplicación de dicha ley en este sector conllevó la puesta en cultivo de un área dedicada tradicionalmente al monte y dehesa que, por las características físicas de este medio y por razones estructura...

  18. Metodología para determinar la fuerza de arrastre de productos agrícolas a partir de la Dinámica de Fluidos Computacional (CFD)

    OpenAIRE

    Alexander Laffita Leyva; Arturo Martínez Rodríguez; Vilma Toledo Dieppa; Yolanda Sabín Rendón; Pedro A. Valdés Hernández

    2014-01-01

    El objetivo del trabajo consiste en obtener una metodología para la determinación, con el apoyo de herramientas de la Dinámica de Fluidos Computacional (CFD), de la fuerza de arrastre en productos agrícolas u otro tipo de sólido sometidos a una corriente de aire. Co- nociendo la distribución de presiones en la superficie y las coordenadas de posición de los nodos de la malla de elementos finitos generada, se elabora una metodología matemática, sobre la base de la geometría analítica y vectori...

  19. Antibacterial Activity of Cold Atmospheric Pressure Argon Plasma against 78 Genetically Different (mecA, luk-P, agr or Capsular Polysaccharide Type) Staphylococcus aureus Strains.

    Science.gov (United States)

    Matthes, Rutger; Lührman, Anne; Holtfreter, Silva; Kolata, Julia; Radke, Dörte; Hübner, Nils-Olaf; Assadian, Ojan; Kramer, Axel

    2016-01-01

    Previous studies on the antimicrobial activity of cold atmospheric pressure argon plasma showed varying effects against mecA+ or mecA-Staphylococcus aureus strains. This observation may have important clinical and epidemiological implications. Here, the antibacterial activity of argon plasma was investigated against 78 genetically different S. aureus strains, stratified by mecA, luk-P, agr1-4, or the cell wall capsule polysaccharide types 5 and 8. kINPen09® served as the plasma source for all experiments. On agar plates, mecA+luk-P-S. aureus strains showed a decreased susceptibility against plasma compared to other S. aureus strains. This study underlines the high complexity of microbial defence against antimicrobial treatment and confirms a previously reported strain-dependent susceptibility of S. aureus to plasma treatment.

  20. Transformaciones agrícolas en el contexto periurbano de la ciudad de San Cristóbal de Las Casas, Chiapas

    Directory of Open Access Journals (Sweden)

    Araceli Calderón Cisneros

    2014-01-01

    Full Text Available San Cristóbal de Las Casas ha crecido en las últimas décadas abarcando las zonas rurales circundantes. El objetivo del presente trabajo consistió en identificar las transformaciones que la interacción urbano-rural imprime sobre la actividad agrícola de un área periurbana: el cerro Huitepec. Se revisó información documental y se levantaron 100 entrevistas abiertas y estructuradas entre población de las localidades rurales e informantes clave. Aunque ha perdido relevancia como fuente de ingresos económicos familiares, la agricultura y la cría de animales de traspatio aún tienen un papel significativo para el autoconsumo familiar.

  1. Modelos de Índice de Difusão para prever a taxa de crescimento do PIB agrícola brasileiro

    Directory of Open Access Journals (Sweden)

    Roberto Tatiwa Ferreira

    2012-07-01

    Full Text Available Este artigo usa modelos lineares e não lineares de Índice de Difusão para prever, um período à frente, a taxa de crescimento trimestral do PIB agrícola brasileiro. Esses modelos são compostos de fatores comuns que permitem redução significativa do número de variáveis explicativas originais. Os resultados de eficiência preditiva apontam para uma superioridade das previsões geradas pelos modelos de Índice de Difusão sobre os modelos ARMA. Entre os modelos de Índice de Difusão, o modelo não linear com efeito threshold superou os resultados do modelo linear e do modelo AR.

  2. La comercialización de maquinaria agrícola en España durante la primera mitad del siglo XX: el ejemplo de Ajuria

    OpenAIRE

    Ojeda San Miguel, Ramón

    2002-01-01

    Este artículo trata de profundízar en la trayectoria de una importante empresa española especializada en la fabricación de maquinaria agrícola durante la primera mitad del siglo XX En el mismo se hace especial referencia a la política de comercialización de las máquinas producidas por las fábricas de la Sociedad. Sin olvidar que también la Empresa se dedicó a la importación de maquinaria de gran volumen. Por lo tanto. se presentan las principales lineas de acción de una Sociedad que intentó, ...

  3. Economía agrícola y circuitos comerciales en el Estado Soberano de Bolívar, 1857- 1886

    Directory of Open Access Journals (Sweden)

    Roicer Alberto Flórez Bolívar

    2012-01-01

    Full Text Available Este artículo estudia la agricultura en el Estado soberano de Bolívar y los circuitos comerciales que se construyeron alrededor de la economía agrícola. La idea central que se defiende es que a pesar de las limitaciones que presentaba la agricultura en cuanto a su nivel de exportación fue capaz de satisfacer las necesidades del mercado interno al ofrecerle a los habitantes del Estado los productos que necesitaban para su sustento y alimentación, permitiendo la creación y consolidación de circuitos comerciales a nivel provincial y comarcano, en los que algunos distritos desempeñaban un papel primordial como centros articuladores.

  4. Estudio y caracterización de la magnetita para su aplicación a la fertilización de suelos agrícolas

    OpenAIRE

    2013-01-01

    En los últimos años hay una preocupación creciente respecto al impacto de las actividades agrícolas en el medio ambiente. Algunos de los principales problemas asociados al uso de fertilizantes son la eutrofización (aumento de la concentración de fósforo y nitrógeno en el agua) y la contaminación por nitratos de las aguas, así como la acumulación de metales pesados en los suelos y su paso a las aguas subterráneas. Por lo tanto, es necesario evitar la entrada de metales tóxicos en los medios ac...

  5. Métodos y usos agrícolas de la ingeniería genética aplicada al cultivo de arroz

    OpenAIRE

    Cristina DiazGranados D.; Alejandro Chaparro-Giraldo

    2012-01-01

    Methods and agricultural uses of genetic engineering applied to rice crop Resumen: En biotecnología de arroz se han logrado avances en transformación genética, con importantes resultados en el mejoramiento genético de variedades elite de las subespecies japónica e índica. Con el propósito de revisar los métodos y los usos agrícolas de la ingeniería genética aplicada al cultivo del arroz, se usaron varias palabras claves en idioma inglés en algunas de las bases de datos de revistas científicas...

  6. Estudio experimental del sistema Hematita/Fosfato para su aplicación a la fertilización de suelos agrícolas

    OpenAIRE

    Ayora Salvo, Victor

    2013-01-01

    En los últimos años la preocupación respecto al impacto de las actividades agrícolas en el medio ambiente se ha visto incrementada. Algunos de los principales problemas derivados del uso de fertilizantes son la eutrofización (aumento de la concentración de fósforo y nitrógeno en el agua) y la contaminación por nitratos de las aguas, así como la acumulación de metales pesados, con su posible bioacumulación en la cadena trófica. Por este motivo es necesario evitar la entrada de los metales pesa...

  7. Estudiar la migración indígena. Itinerarios de vida de trabajadores agrícolas en el noroeste mexicano

    Directory of Open Access Journals (Sweden)

    Laura Velasco-Ortiz

    2014-01-01

    Full Text Available La presente investigación es un ejercicio metodológico en el cual se analizan las múltiples lógicas que definen la movilidad y la migración de poblaciones indígenas, cuyas vidas se interrelacionan con el desarrollo de los mercados de trabajo agrícola de exportación y la creación de nuevas regiones en la frontera norte de México. El análisis de dicha movilidad parte de entrevistas biográficas, lo cual nos permite observar a partir de qué condiciones se suscita el desplazamiento de los jornaleros y la migración, así como el proceso de asentamiento en nuevos lugares.

  8. La intensificación agrícola y la diversidad vegetal en los sistemas cerealistas de secano mediterráneos: implicaciones para la conservación

    Directory of Open Access Journals (Sweden)

    F.X. Sans

    2013-01-01

    Full Text Available El trabajo analiza la importancia de la diversidad vegetal en los agroecosistemas y los efectos de la intensificación de las prácticas agrícolas y del paisaje sobre la diversidad vegetal. La revisión de diversos estudios llevados a cabo por el equipo de investigación permite destacar que la intensificación agrícola, tanto a escala de campo como de paisaje, afecta negativamente la abundancia y la riqueza específica de la flora. La comparación de la flora arvense de los cultivos cerealistas de secano mediterráneos entre los años 50 y la actualidad refleja la reducción de la flora arvense, especialmente de la flora propia de las mieses y la disminución de la abundancia de grupos funcionales como las leguminosas y las plantas entomófilas. El efecto de las prácticas agrícolas y de la complejidad del paisaje varía en función de la flora estudiada. Así, la complejidad del paisaje es el principal factor que afecta la configuración de la vegetación de los márgenes, mientras que la intensidad de las prácticas agrícolas es el principal factor para explicar las diferencias en la flora arvense en el centro de los campos. Por último, el artículo analiza diversas propuestas para la gestión de los agrosistemas con el objetivo de conciliar la producción agrícola y la conservación de la biodiversidad en la región mediterránea.

  9. Análisis de neumático por elementos finitos con vistas a la determinación de coeficientes de cargas dinámicas en estructuras de máquinas agrícolas

    Directory of Open Access Journals (Sweden)

    Raudel Flores Moreno

    2010-01-01

    Full Text Available Las complejidades asociadas al cálculo con exactitud de coeficientes de cargas dinámicas en estructuras de máquinas agrícolas sometidas a cargas de impacto, traen aparejadas otras dificultades relacionadas con el sobredimensionado de las piezas, lo cual da lugar a exceso de peso y gastos adicionales. En el caso de las máquinas agrícolas es de vital importancia el estudio de los sistemas de amortiguación, ya que éstos son capaces de absorber parte de las cargas de impacto disminuyendo las afectaciones que éstas provocan en las estructuras. En el presente trabajo se abordan métodos de cálculo mediante modelación con herramientas de diseño asistido por computadora y análisis por elementos finitos con vistas a conocer la influencia de la presencia de neumáticos en la disminución de los coeficientes de cargas dinámicas que se introducen durante el cálculo de estructuras de máquinas agrícolas sometidas a cargas de impacto. Como resultado de la simulación y evaluación del modelo para un caso concreto, se obtuvo que un neumático típico de maquinas agrícolas (7.50-20-6 con una presión de inflado de 3,10 kg/cm2 fue capaz de reducir en un 17,54 % los coeficientes de cargas dinámicas a aplicar durante el cálculo de resistencia del puente trasero de un remolque agrícola típico de 4 t, suponiendo un impacto provocado por una altura de caída de solo 5 cm.

  10. La sequía meteorológica y la variación de la superficie agrícola en la Isla de Margarita, estado Nueva Esparta, Venezuela período 1972-2004

    Directory of Open Access Journals (Sweden)

    Eva Colotti

    2013-01-01

    Full Text Available El fenómeno de la sequía se relaciona con la disminución de la precipitación pluvial que afecta al ecosistema y la economía. Para conocer su comportamiento se caracterizó espacial y temporalmente la sequía meteorológica en la isla de Margarita, para el periodo 1972–2004, determinando su magnitud mediante el Índice de Precipitación Estandarizada. La Variación de la superficie agrícola fue analizada con el Índice de Dinámica Agrícola, para determinar el aumento o disminución. En Margarita los meses secos son abril y mayo y los húmedos junio y diciembre, donde la sequía meteorológica se categorizó de ligeramente seco a sequía extrema, con secuencias secas más largas en duración trimestral; y a 12 y 24 meses, las secuencias se categorizaron de normal a ligeramente húmedo. Aun cuando la agricultura no es una actividad relevante, la superficie agrícola aumentó 74% para el periodo 1993-2004, rechazando la hipótesis sobre su disminución. En conclusión, la sequia se incrementó, llegando a valores SPI inferiores a 1.5 categorizados como sequia extrema, al igual que la superficie agrícola; sin embargo, la relación de aumento o disminución entre ambas variables, no es directamente proporcional; siendo más favorable la ubicación de áreas agrícolas en zonas donde la sequía tiene menor influencia.

  11. Análisis multivariado de propiedades químicas en Oxisoles con diferentes niveles de intervención agrícola

    Directory of Open Access Journals (Sweden)

    Camacho-Tamayo Jesús H.

    2010-09-01

    Full Text Available La intervención humana en la producción agrícola influye directamente en la calidad del suelo, promoviendo alteraciones en las propiedades físicas y químicas, mediante el uso de fertilizantes, correctivos y prácticas de labranza. El objetivo del presente trabajo fue evaluar los cambios en las propiedades químicas de dos Oxisoles (Typic Hapludox y Typic Haplustox, con diferentes niveles de intervención (cultivos de pasto Brachiaria y rotaciones de maíz y soya, en el municipio de Puerto López (Meta-Colombia. Las muestras fueron tomadas en 42 puntos, distanciados 25 m perpendicularmente, entre 0 y 0.10 m y 0.10 y 0.20 m de profundidad, para un total de 168 muestras en los dos lotes. Los datos fueron analizados mediante análisis de varianza y técnicas de análisis multivariado, a través de componentes principales y agrupamiento jerárquico. Las propiedades estudiadas fueron carbono orgánico, pH, acidez intercambiable, aluminio intercambiable, P, Ca, Mg, P, Na, capacidad de intercambio catiónica efectiva (CICE, suma de bases y saturación de bases. La intervención agrícola se ve reflejada principalmente en la capa superficial del suelo, donde se presentaron los mayores valores de CO, Ca, Mg, K, P, SB y CICE, debido a la presencia de residuos de cosecha, así como a la aplicación de fertilizantes y correctivos.

  12. Aptidão agrícola de terras com estimativa de risco climático para a cultura do milho utilizando geoprocessamento

    Directory of Open Access Journals (Sweden)

    M. J. S. Godoy

    2002-09-01

    Full Text Available O objetivo deste trabalho foi determinar a aptidão agrícola das terras para cultura do milho em sistema de produção tecnificado, a partir de dados extraídos de levantamento de solos em escala 1:50.000 e da estimativa do risco climático, usando um sistema de informações geográficas. A área de estudo foi a bacia hidrográfica do rio Jardim, no Distrito Federal. Utilizou-se um modelo de balanço hídrico para simular o risco climático para a cultura do milho (Zea mays L., considerando nove datas de plantio. Foram definidos valores quantitativos para cada um das propriedades condicionadoras da produtividade do milho em áreas de cerrado e, por meio de algoritmos de lógica booleana estabelecidos com base em critérios definidos em tabelas-guia previamente elaboradas, foram realizados cruzamentos consecutivos que permitiram a elaboração de mapas de aptidão agrícola das terras para a cultura do milho, com cinco classes, que evidenciaram a variação temporal da aptidão. Constatou-se que 66,5 % da área total não apresentou limitações físicas, 96% das terras foram restritas em fertilidade e o período de menor risco climático foi de 11 a 20/10.

  13. Determinación de la adsorción de cadmio mediante isotermas de adsorción en suelos agrícolas venezolanos

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    Nereida Sánchez

    2011-04-01

    Full Text Available El cadmio es un metal pesado que tiende a acumularse en la superficie del suelo. En los últimos años, las actividades antropogénicas han ocasionado un incremento en los niveles de este metal en suelos agrícolas generando gran preocupación ambiental debido a su movilidad y lixiviación en el perfil del suelo y a la facilidad con que es absorbido por las plantas. El objetivo de este trabajo fue determinar la capacidad de adsorción de cadmio, de cuatro suelos venezolanos de uso agrícola con diferencias texturales. Para determinar la capacidad de adsorción del metal en cada suelo, inicialmente se determinó el tiempo óptimo de agitación; el cual fue de 2 horas y la relación suelo-solución enriquecedora de Cd; la cual fue de 1:50. Con estos parámetros se elaboraron las isotermas de adsorción para los suelos y se compararon los modelos de Freundlich y Langmuir. Los resultados mostraron que el modelo matemático de Freundlich es el que mejor describe la cinética de la reacción y la capacidad de adsorción de Cd por los suelos, siendo los que poseen mayores contenidos de arcilla, MO y pH ácidos los de mayor capacidad de adsorción.

  14. Uso de las imágenes de satélites y los SIG en el campo de la Ingeniería Agrícola

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    Dámaso Ponvert Delisles

    2013-01-01

    Full Text Available Los sistemas de ingeniería agrícola constituyen conjuntos de técnicas y tecnologías que garantizan la producción agropecuaria. Por lo general, ellos producen determinados impactos al medio ambiente, que tienen consecuencias negativas sobre los recursos naturales produciendo huellas en el territorio. En la actualidad se aplican con éxito tecnologías muy eficaces como la Teledetección y, los SIG para identificar la huella espacial de estos impactos y apoyar las decisiones que ayuden a los directivos a tomar medidas correctivas y prospectivas. El objetivo de este trabajo es identificar las tareas más susceptibles de aplicar las tecnologías de Teledetección y los SIG en la evaluación de impactos provocados por el empleo de equipamiento y tecnologías del campo de la Ingeniería Agrícola. Para cumplimentarlo, se caracterizan los impactos asociados con el laboreo del suelo, con reade las imágenes de satélites y los SIG y se demuestra su uso en el caso concreto del mal manejo de métodos y sistemas de riego. Se explica la obtención de un cartograma de salinidad de un bloque cultivado con caña de azúcar usando técnicas de teledetección y redes neuronales artificiales. Como conclusión se reafirma la necesidad e importancia de la capacitación en el empleo de estas tecnologías para alcanzar mayor eficiencia en la sostenibilidad medioambiental.

  15. A unified theory of autism revisited: linkage evidence points to chromosome X using a high-risk subset of AGRE families.

    Science.gov (United States)

    Allen-Brady, Kristina; Cannon, Dale; Robison, Reid; McMahon, William M; Coon, Hilary

    2010-04-01

    Zhao et al. [2007] in their "Unified Theory of Autism" hypothesized that incidence of autism in males could be explained by essentially two types of family structures: majority of autism cases are from low-risk autism families with de novo mutations, and a minority of cases are from high-risk multiplex families, where risk to male offspring approximates 50% consistent with a dominant model and high penetrance. Using the Autism Genetic Resource Exchange (AGRE) data set, Zhao et al. identified 86 high-risk families with likely dominant transmission. As genotype data are now available for many members of the AGRE resource, the objective of this manuscript was to determine if dominant linkage evidence for an autism predisposition gene exists in these 86 high-risk families. HumanHap550K Illumina SNP data were available for 92% of 455 total family members in these 86 high-risk families. We performed a linkage analysis using a pruned subset of markers where markers in high linkage disequilibrium were removed. We observed a single suggestive peak (maximum LOD 2.01, maximum HLOD 2.08) under a dominant model on chromosome Xp22.11-p21.2 that encompasses the IL1RAPL1 gene. Mutations or deletions in IL1RAPL1 have been previously reported in three families with autism. In our study, 11 families contributed nominally (P0.588) to the chromosome X peak. These results demonstrate that identification of a more homogeneous subset of autism cases, which was based on family structure in this study, may help to identify, localize and further our understanding of autism predisposition genes.

  16. Paisaje agrario y prácticas agrícolas en la Ribeira Sacra (Galicia durante los siglos XIV y XV

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    López Sabatel, José Antonio

    2008-06-01

    Full Text Available The aim of this article is to approach what appears to be the physical contour and extent of the land recovered for agricultural use at the heart of the area falling under the influence of five monasteries situated on both banks of the River Sil in the stretch immediately preceding its flowing into the mouth of the Miño during the 14th and 15th centuries. It will also focus on the various agrarian practices used in chestnut and vine cultivation as well as work on the lands growing cereal crops. These are practices which in the relative system of cultivation will have an effect on the physiognomy of the agrarian lands throughout this period.

    Este artículo pretende un acercamiento a lo que debió ser el semblante físico y extensión de los terrenos ganados en beneficio de la actividad agrícola en el seno del área de influencia de cinco cenobios situados a ambos márgenes del río Sil en el tramo precedente a su desembocadura en el Miño durante los siglos XIV y XV. También se centrará en las diversas prácticas agrícolas destinadas al cuidado de la castaña y la vid así como al trabajo en las tierras de cereal. Prácticas éstas que en lo relativo al sistema de cultivos tendrán incidencia en la fisonomía del espacio agrario a lo largo de este periodo.

  17. Análise e Diagnóstico de uma Unidade de Produção Agrícola Familiar

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    Emerson Juliano Lucca

    2012-09-01

    Full Text Available Os produtores em geral necessitam de um assessoramento administrativo, visando uma maior geração de renda na unidade de produção. As inúmeras experiências de trabalho, realizadas na área da administração rural, baseiam-se praticamente no método contábil. Porém este método exige procedimentos demorados e complexos, o que requer maior disponibilidade de tempo do produtor para a obtenção dos dados. Em contrapartida, o método de enquete, que será estudado, é mais ágil e sucinto, pois é baseado em uma entrevista com o produtor, onde o técnico recolhe informações sobre a estrutura e o funcionamento da unidade produtiva e propõem alternativas que visam melhorar os sistemas de produção. Sobre este método faltam ainda estudos para avaliar sua pertinência e eficácia. O estudo tem como objetivo principal analisar uma unidade de produção agrícola familiar, localizada na região noroeste do Estado Rio Grande do Sul, onde se concretizou uma entrevista com o proprietário para a caracterização da unidade de produção agrícola. Os dados obtidos foram através do método de entrevista com o produtor além de uma visita ao produtor para diagnosticar melhor a estrutura desta unidade de produção. A análise e o diagnóstico levaram em conta a prática administrativa do produtor, completando os aspectos técnicos e econômicos do sistema de produção. 

  18. Surface coatings that promote rapid release of peptide-based AgrC inhibitors for attenuation of quorum sensing in Staphylococcus aureus.

    Science.gov (United States)

    Broderick, Adam H; Stacy, Danielle M; Tal-Gan, Yftah; Kratochvil, Michael J; Blackwell, Helen E; Lynn, David M

    2014-01-01

    Staphylococcus aureus is a major human pathogen responsible for a variety of life-threatening infections. The pathogenicity of this organism is attributed to its ability to produce a range of virulence factors and toxins, including the superantigen toxic shock syndrome toxin-1 (TSST-1). While many S. aureus infections can be treated using conventional antibiotics, strains resistant to these bactericidal agents have emerged. Approaches that suppress pathogenicity through mechanisms that are nonbactericidal (i.e., antivirulence approaches) could provide new options for treating infections, including those caused by resistant strains. Here, we report a nonbactericidal approach to suppressing pathogenicity based on the release of macrocyclic peptides (1 and 2) that inhibit the agr quorum sensing (QS) circuit in group-III S. aureus. It is demonstrated that these peptides can be immobilized on planar and complex objects (on glass slides, nonwoven meshes, or within absorbent tampons) using the rapidly dissolving polymer carboxymethylcellulose (CMC). Peptide-loaded CMC films released peptide rapidly (95%) inhibition of the agr QS circuit without inducing cell death when incubated in the presence of a group-III S. aureus gfp-reporter strain. Peptide 1 is among the most potent inhibitors of QS in S. aureus reported to date, and the group-III QS circuit regulates production of TSST-1, the primary cause of toxic shock syndrome (TSS). These results thus suggest approaches to treat the outer covers of tampons, wound dressings, or other objects to suppress toxin production and reduce the severity of TSS in clinical and personal care contexts. Because peptide 1 also inhibits QS in S. aureus groups-I, -II, and -IV, this approach could also provide a pathway for attenuation of QS and associated virulence phenotypes in a broader range of contexts.

  19. A "reforma agrária assistida pelo mercado" do Banco Mundial no Brasil: dimensões políticas, implantação e resultados

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    João Márcio Mendes Pereira

    2011-12-01

    Full Text Available O artigo analisa a implementação e os resultados do projeto piloto Cédula da Terra (1997-2002 e a sua continuidade, a partir de 2003, por meio do Programa Nacional de Crédito Fundiário. Tais iniciativas foram inspiradas na proposta de "reforma agrária assistida pelo mercado", impulsionada pelo Banco Mundial em diversos países, em particular na América Latina, a partir de 1994, como alternativa à reforma agrária, a qual está em curso, nos dias atuais, apenas no Brasil. Com base em pesquisas empíricas, argumenta-se que o Cédula da Terra, ao contrário do que afirma o Banco Mundial, não foi bem sucedido em prover um modelo de acesso à terra a ser reproduzido em maior escala. Este artigo faz ainda um balanço dos desdobramentos desse modelo na política fundiária do governo Luis Inácio Lula da Silva (2003-2010.This article surveys the implementation and results of a pilot project called Cédula da Terra (1997-2002 and its continuity through the National Credit for Land, after 2003, in Brazil. These programs were inspired in a model called "market-assisted land reform", financed by the World Bank and implemented in several countries, particularly in Latin America, starting in 1994 as an alternative to agrarian reform, which is basically active in Brazil today. Based on data of empirical researches it is argued that the Cédula da Terra was not well-succeeded in providing a model of access to land replicable on a larger scale, as the World Bank has been arguing. Furthermore, the article evaluates the developments of this model in the land policies of Luis Inácio Lula da Silva's Government (2003-2010.

  20. Modelo de desenvolvimento, agrotóxicos e saúde: um panorama da realidade agrícola brasileira e propostas para uma agenda de pesquisa inovadora

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    Marcelo Firpo Porto

    Full Text Available O modelo agrário hegemônico no Brasil está baseado em monocultivos para exportação que são intensivos em tecnologias mecanizadas e no uso de agrotóxicos. O país tornou-se o principal consumidor mundial de agrotóxicos e é avaliado como o mercado que mais crescerá num futuro próximo. Este trabalho teve como propósito fazer uma avaliação geral da relação entre o modelo agrário brasileiro e os impactos à saúde e ao ambiente decorrentes do uso de agrotóxicos e propor uma agenda de pesquisa para subsidiar o enfrentamento dos problemas apontados que integre os setores comprometidos com a defesa da saúde, do meio ambiente e da segurança e soberania alimentar. Constatou-se e discutiu-se a necessidade de: dar maior visibilidade aos efeitos e aos custos socioambientais e de saúde do modelo predominante; utilizar instrumentos econômicos para incentivar o uso de tecnologias mais limpas e modelos de produção mais saudáveis, compatíveis com a agricultura familiar, e para desestimular os modelos que oferecem mais riscos à saúde e ao ambiente; desenvolver e implementar políticas públicas baseadas em referenciais da economia ecológica e da agroecologia, com a participação de movimentos sociais, das instituições reguladoras e de grupos de pesquisa.

  1. Análisis multivariado de propiedades químicas en Oxisoles con diferentes niveles de intervención agrícola

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    Jesús H Camacho-Tamayo

    2010-07-01

    Full Text Available La intervención humana en la producción agrícola influye directamente en la calidad del suelo, promoviendo alteraciones en las propiedades físicas y químicas, mediante el uso de fertilizantes, correctivos y prácticas de labranza. El objetivo del presente trabajo fue evaluar los cambios en las propiedades químicas de dos Oxisoles (Typic Hapludox y Typic Haplustox, con diferentes niveles de intervención (cultivos de pasto Brachiaria y rotaciones de maíz y soya, en el municipio de Puerto López (Meta-Colombia. Las muestras fueron tomadas en 42 puntos, distanciados 25 m perpendicularmente, entre 0 y 0.10 m y 0.10 y 0.20 m de profundidad, para un total de 168 muestras en los dos lotes. Los datos fueron analizados mediante análisis de varianza y técnicas de análisis multivariado, a través de componentes principales y agrupamiento jerárquico. Las propiedades estudiadas fueron carbono orgánico, pH, acidez intercambiable, aluminio intercambiable, P, Ca, Mg, P, Na, capacidad de intercambio catiónica efectiva (CICE, suma de bases y saturación de bases. La intervención agrícola se ve reflejada principalmente en la capa superficial del suelo, donde se presentaron los mayores valores de CO, Ca, Mg, K, P, SB y CICE, debido a la presencia de residuos de cosecha, así como a la aplicación de fertilizantes y correctivos.

  2. A Comparative Study of Dihydroartemisinin Compounds in Treatment of Uncomplicated Falciparum Malaria in Kampong of Cambodia

    Institute of Scientific and Technical Information of China (English)

    SONGJian-ping; DuongSocheattffu

    2003-01-01

    Objective:To compare the safety and efficacy of two compounds of dihydroartemisinin (DHA)-Artekin and Artekin(T)in the treatement of uncomplicated falciparum malaria.Methods:The regiment of 8-tablet for 2 days of Artekin and Artekin(T) were applied to 100 patients with uncompli-cated falciparum malaria,who were radomly divided into two groups.Each group contained 50 cases.The cure rate ,the mean parasites clearance time,the mean fever clearance and side-effects were observed to assess the safety and efficacy of the compunds used.Results:The mean parasites clearance time was 31.7±9.0 hours in the Artekin group and 32.8±8.8 hours in Artekin(T) group respectively; the mean fever clearance time was 12.7±7.2 hours in Artekin group and 16.5±7.9 hours in Artekin(T) group; there were no recrudescence case in both groups within the 28 days of follow-up ,the cure rates in Artekin group and Artekin(T)groups were 100%.It indicated that the tolerability of both compunds were very good,the side-effects such as nausea,abdominal pain were mild and self-limited.Conclusion:The study preliminarily indicated that the DHA and PQ compounds were of high efficacy,rapid acting and low toxici-ty.Artekin is very promising as a cheap,simple,effective treatment for multi-resistance malaria in Cam-bodia.

  3. A Comparative Study of Dihydroartemisinin Compounds in Treatment of Uncomplicated Falciparum Malaria in Kampong of Cambodia

    Institute of Scientific and Technical Information of China (English)

    SONG Jian-ping(宋建平); Duong Socheat; Suou Seila

    2003-01-01

    Objective: To compare the safety and efficacy of two compounds of dihydroartemisinin (DHA) Artekin and Artekin (T) in the treatment of uncomplicated falciparum malaria. Methods: The regimen of 8-tablet for 2 days of Artekin and Artekin (T) were applied to 100 patients with uncomplicated falciparum malaria, who were randomly divided into two groups. Each group contained 50 cases. The cure rate, the mean parasites clearance time, the mean fever clearance and side-effects were observed to assess the safety and efficacy of the compounds used. Results: The mean parasites clearance time was 31.7±9.0 hours in the Artekin group and 32.8±8.8 hours in Artekin (T) group respectively;the mean fever clearance time was 12.7±7.2 hours in Artekin group and 16.5±7.9 hours in Artekin (T) group; there were no recrudescence case in both groups within the 28 days of follow-up,the cure rates in Artekin group and Artekin (T) groups were 100%. It indicated that the tolerability of both compounds were very good, the side-effects such as nausea, abdominal pain were mild and self-limited. Conclusion: The study preliminarily indicated that the DHA and PQ compounds were of high efficacy, rapid acting and low toxicity. Artekin is very promising as a cheap, simple, effective treatment for multi-resistance malaria in Cambodia.

  4. Ethnography-Architecture in Kampong Kauman Semarang: A Comprehension of Cultural Toward Space

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    B. A. Suprapti

    2010-01-01

    Full Text Available Problem statement: During the last fifty years, there have been significant changes on the perspectives of space. Space definition not only involves physical features but also deals with social capital for human development. Regarding this matter, the research puts the perspective of space as a subject or as a work of art that needs better comprehension rather than considering it as merely an object or fact. Kampung Kauman is a traditional Moslem village located around the Grand Mosque in some cities of Java. In the city of Semarang, Kauman area is an expression of human culture built up over times and experiences for three centuries. Approach: The study applies investigative-method on the transcendental aspects of space by using ethnography-architecture. The classification of ethnography-architecture concentrates on single case. The method applies approaches on culture and design and also participant observation as research tools which will be concluded with open themes. Results: After observing Kauman Pompa Semarang, the research discovers local concepts of ‘the charity space’ and ‘the social intensive space’. Conclusion: The research is a unique knowledge for architecture since the approach on culture reveals the role of Islamic culture in establishing kampung Kauman (Kauman village. Ethnography-architecture is applicable to other researches in investigating the original space concept.

  5. El Perfil de Egreso del Ingeniero Agrónomo. Una Experiencia de Grupos de Discusión con Egresados El Perfil de Egreso del Ingeniero Agrónomo. Una Experiencia de Grupos de Discusión con Egresados

    Directory of Open Access Journals (Sweden)

    Gabriel Córdova Duarte

    2012-02-01

    Full Text Available Se presenta un estudio de grupos de discusión en panel con ingenieros agrónomos de la Universidad de Guanajuato para determinar el perfil de salida de dicha licenciatura. Los egresados sugieren: mantener las prácticas en unidades agropecuarias, mejorar las habilidades de manejo de maquinaria y equipo agrícola, fortalecer el área básica agronómica, fomentar la visión empresarial, de comercialización, de calidad de procesos y productos, formular y evaluar proyectos productivos, formar líderes y emprendedores, desarrollar la creatividad, puntualidad, constancia, disciplina, relaciones humanas, profundizar la formación humanista y, formar con el ejemplo; vincular dependencia con egresados y universidades, al profesor y la investigación con empresas agropecuarias.This work presents a study of discussion groups in a panel with agronomist of the Universidad of Guanajuato to determine the bachelors degree graduate profile. The graduates suggested: to keep the practices in agricultural units, to improve the operating skills on agricultural and machinery equipment, to strengthen the basic agronomic area, to foment the management vision of commercialization, of products and of quality processes, formulate and evaluate productive projects, upbringing leaders and entrepreneurs; to develop creativity, punctuality, perseverance, discipline and humane relationship, to strengthen the humanist education and education by example; to create bonds between the school, the graduates, the universities, the teacher and the research with agricultural enterprises.

  6. Integração vertical como estratégia de apropriação de valor: um estudo exploratório no canal de distribuição de produtos agrícolas Alternative marketing channels in order to attenuate the power of retail chains: agrícola Pedra Branca case study

    Directory of Open Access Journals (Sweden)

    Vivian Lara dos Santos Silva

    2009-03-01

    Full Text Available Neste artigo, investiga-se a adoção de canais alternativos para a comercialização de produtos agrícolas como forma de atenuar o poder, cada vez maior, exercido pelas grandes redes varejistas. O artigo investiga a decisão - e os efeitos daí decorrentes - de uma determinada empresa sediada no interior paulista, agrícola Pedra Branca, quanto à operacionalização verticalizada de uma butique de frutas, legumes e verduras (FLVs. Consciente dos novos padrões demandados pelo consumidor, a estratégia da empresa alvo do estudo foi combinar a oferta regular de produtos frescos, de qualidade intrínseca padronizada e preços atrativos, a um serviço diferenciado, baseado em um alto valor na experiência de compra. Esta estratégia fundamenta-se no anseio dos consumidores de, mais do que simplesmente adquirir produtos, experimentar sensações, as quais vividas em momentos de lazer exerceriam um grande poder de diferenciação. Realizou-se um estudo de caso baseado em entrevistas em profundidade semiestruturadas com diretores e gerentes da empresa. Como resultado, as evidências empíricas sugerem: 1 a verticalização (integração vertical da atividade de comercialização como uma alternativa para a apropriação de valor da produção ao longo do canal de distribuição; e 2 o desafio da gestão do suprimento como requisito-chave para a adequada gestão do valor de uma marca. Considera-se oportuno lembrar, porém, que, em decorrência das limitações próprias da metodologia de estudos de caso, estas tais evidências devem ser entendidas como proposição a ser testada em trabalhos quantitativos futuros, ou mesmo melhor embasada via condução de estudos multicaso.This paper aims to analyze the search for alternative marketing channels of industry and rural producers in order to attenuate the power of retail chains over the sale of products and services. In special, we focus on the rural producers' perspective investigating the decision of

  7. Erosión y pérdida de nutrientes en diferentes sistemas agrícolas de una microcuenca en la zona periurbana de la ciudad de Puebla, México

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    Rosalía Castelán Vega

    2017-07-01

    Full Text Available El suelo es un componente natural de gran importancia en la sostenibilidad de los ecosistemas, su degradación se debe, en la mayoría de los casos, al mal manejo bajo condiciones de ladera, lo que disminuye su productividad y su capacidad para sostener la vida humana. Se evaluó la producción de sedimentos y la pérdida de nutrientes durante el año 2013 en sistemas agrícolas representativos de la zona periurbana de la ciudad de Puebla, México; con el objetivo de ponderar el coeficiente de enriquecimiento de dichos sedimentos, y así identificar el sistema agrícola que menor perdida de fertilidad genera. Se instalaron parcelas delimitadas con dimensiones de 3 m de ancho y 9 m de largo con pendiente homogénea de 9% de inclinación, en los sistemas: maíz, maíz-calabaza y maíz-avena. Se recolectaron los sedimentos, a los cuales se les determinó la concentración de materia orgánica, nitrógeno y fósforo, según lo marca la NOM-021-SEMARNAT-2000. La producción de sedimentos y escorrentía fue significativamente mayor en el sistema agrícola de maíz (54.6 mm y 37.9 Mg ha‑1, respectivamente y menor en maíz-calabaza. Los coeficientes de enriquecimiento de los sedimentos erosionados fueron en su mayoría, superiores a la unidad, destacando la materia orgánica con los coeficientes más altos. Se observó una fuerte correlación entre la producción de sedimentos y las pérdidas de materia orgánica, nitrógeno y fósforo, en los sistemas agrícolas. Los resultados obtenidos demuestran que el actual manejo de los cultivos agrícolas en la zona de estudio, favorecen la degradación de los suelos. De igual forma, los resultados generados son una base importante para establecer estrategias agrícolas y disminuir áreas degradadas en los espacios rurales de la zona periurbana de la ciudad de Puebla, México.

  8. Uso de imagens orbitais como base de dados para projetos de reforma agrária The use of orbital images as subsidies to agrarian reform projects

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    Marina de Fátima Vilela

    2005-08-01

    Full Text Available Análises técnica e econômica foram realizadas em imagens dos sensores IKONOS, TM/Landsat 5, ETM+/Landsat 7 e CCD/CBERS, objetivando a verificação da viabilidade destas como base de dados em projetos de reforma agrária. Essas análises efetuadas e a situação de mercado indicaram que a imagem IKONOS apresenta excelente desempenho técnico, mas o custo de aquisição inviabiliza sua utilização como base de dados para a reforma agrária. A imagem do Landsat 7, com baixo custo de aquisição, apresentou grande viabilidade técnica para fins de reforma agrária. No entanto, a perda do contato com a plataforma Landsat 7 inviabilizou a compra de novas imagens do sensor ETM+. A imagem CCD/CBERS apresentou a segunda maior similaridade com a verdade de campo e o menor índice Kappa para a classificação. Apesar do baixo índice de exatidão para a classificação, as análises de custo, o lançamento do CBERS-2 e a possibilidade de correção dos problemas de radiometria podem tornar as imagens da plataforma CBERS-2 concorrentes de peso no mercado e, ainda, preencher a lacuna deixada pela perda do Landsat 7. A imagem do Landsat 5 apresentou o mais baixo desempenho técnico nas análises efetuadas. Entretanto, seu potencial como base de dados é amplamente reconhecido pelo INCRA, que ainda utiliza tais imagens. O declínio da vida útil do Landsat-5 atribui mais importância ao lançamento do CBERS-2.Technical and economical analyses were performed on IKONOS, Landsat TM 5 and Landsat ETM+ 7 and CCD/CBERS data in order to verify their feasibilities to subsidy agrarian reform projects. Results showed that IKONOS data presented excellent technical viability but its high cost prevents its use. Landsat ETM+ 7 data, with low cost, presented good technical viability, however due to the problems occurring in the satellite operation, its use was also prevented . CCD/CBERS data presented the second best similarity with the ground truth data, although it

  9. As atitudes dos agricultores face à política agrícola comum e ao projecto de regadio de alquev

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    Maria José Palma Lampreia dos Santos

    2011-03-01

    Full Text Available O principal objectivo deste artigo é conhecer as atitudes dos agricultores face à produção agrícola, ao apoio político e ao projecto de rega de Alqueva numa micro-região mediterrânica do Sul de Portugal, no contexto da Política Agrícola Comum (PAC de 2003 e do Health-Check. Simultaneamente, pretende-se conhecer as intenções comportamentais destes agricultores frente à inovação tecnológica e ao futuro regadio público neste contexto político. Os resultados destacam que a grande maioria destes agricultores constituem um grupo relativamente homogéneo face às suas atitudes. Este cluster mantém uma mentalidade muito produtivista, um forte desejo de manter um foco agrícola, rejeitando veementemente noções de liberalização política. Apesar de possuírem elevada capacidade inovadora e de estarem conscientes da importância do seu contributo na defesa do mundo rural, reconhecem que as futuras condições institucionais da PAC, do fornecimento da água do regadio de Alqueva e das condições de acesso ao crédito, lhes poderá comprometer os seus planos inovadores no futuro. Por isso, conclui-se que é necessário compreender as especificidades da agricultura regional nos diversos países da União Europeia para que as políticas tenham êxito local. No caso português, são necessários estudos mais abrangentes de forma a encontrar resultados mais consistentes.The main purpose of this paper is to know farmer' attitudes face to the agricultural production, the political support and the irrigation project of Alqueva in the context of the 2003 Common Agricultural Policy (CAP reform and the Health-Check, in a micro-region located near the Mediterranean Sea, in the Southern region of Portugal. At the same time, this paper also aims to understand the behavioural intentions of farmers face to the technological innovation and the future of the irrigation project in this political context. Results show that the majority of farmers are a

  10. Respuesta de Leucaena leucocephala cv. Perú a la aplicación de diferentes dosis de MicoFert agrícola

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    L Ojeda

    Full Text Available Se realizó una investigación en la Empresa Pecuaria El Tablón (Cumanayagua, provincia Cienfuegos, Cuba, con el objetivo de evaluar el efecto que ejerce la aplicación de diferentes dosis de MicoFert agrícola sobre la producción de materia seca (MS y el contenido de fósforo foliar en Leucaena leucocephala cv. Perú. El diseño fue de bloques al azar, con seis tratamientos y tres réplicas. Los tratamientos estuvieron constituidos por cuatro dosis de MicoFert (250, 500, 750 y 1 000 g/m-1, una variante a razón de 25 kg de N ha-1, y el control. El experimento tuvo una duración de dos años; se realizaron cuatro cortes por año, con una frecuencia de 90 días, a una altura de 25 cm sobre el suelo. La aplicación de MicoFert agrícola incrementó el rendimiento de MS entre 13 y 40 %, de forma proporcional a las dosis aplicadas, respecto al control. El rendimiento más alto de MS (18,44 t ha-1 se obtuvo con la aplicación de nitrógeno, y difirió significativamente del resto de los tratamientos. Fue evidente el efecto que ejerció la inoculación con el biofertilizante en el contenido de fósforo foliar, el cual mostró diferencias significativas entre las variantes con MicoFert y el control. La colonización de raicillas por los hongos micorrízicos arbusculares (HMA fue proporcional al incremento de las dosis de biofertilizante, con valores de 34, 38, 44 y 49 %, respectivamente. La fertilización con nitrógeno y el control presentaron 28 y 26 % de colonización micorrízica, lo que indicó la presencia de HMA nativos.

  11. Uma perspectiva evolucionária da economia agrícola: o caso da produção ovina no Brasil e Uruguai

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    João Garibaldi Almeida Viana

    2014-09-01

    Full Text Available O objetivo do artigo é desenvolver conceitos institucionais e evolucionários a fim de subsidiar a análise de mercados agrícolas. A construção teórica e analítica foi aplicada no caso da evolução da ovinocultura para responder à questão: variáveis institucionais e evolucionárias são determinantes para o aumento da produção de ovinos no Brasil e no Uruguai? A hipótese da pesquisa reside na importância das variáveis institucionais e evolucionárias no processo produtivo, sendo decisivo o papel das regras informais e da dinâmica econômica para o desenvolvimento futuro da atividade. Os dados do caso empírico foram analisados por meio de testes de hipóteses paramétricos e análise de regressão logística. Os resultados encontrados demonstram que fatores institucionais foram determinantes, tanto na manutenção de ovinocultores após um processo de mudança estrutural, como na pretensão futura de aumento da produção ovina nas duas regiões estudadas, apontando um papel decisivo para as regras informais da sociedade (costumes, tradições etc. e modos não econômicos de pensar na dinâmica econômica da atividade após períodos de desequilíbrios. A pesquisa demonstrou a possibilidade da aplicação de pressupostos econômicos evolucionários, buscando, além de compreender o fenômeno, estimular o fortalecimento desta aproximação teórico-empírica em diversos temas da área da economia agrícola.

  12. Impactos dos subsídios agrícolas dos Estados Unidos na expansão do agronegócio brasileiro

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    Adelson Martins Figueiredo

    2010-06-01

    Full Text Available Nos fóruns de negociações multilaterais da Organização Mundial de Comércio subsiste veemente debate com intuito de eliminar as subvenções agrícolas nos países desenvolvidos. Contudo, os Estados Unidos têm aumentado o volume desses subsídios, causando distorções no comércio agrícola mundial. Assim, o objetivo desta pesquisa foi avaliar os impactos desses subsídios norte-americanos (Loan Deficiency Payments, concedidos no período de 2002 a 2007, sobre o crescimento do agronegócio brasileiro. Os resultados permitem inferir que a redução dos subsídios nos EUA propiciaria o crescimento da produção agroindustrial brasileira e ampliaria o superávit na balança comercial desse setor, com crescimento conjunto das exportações e importações. Portanto, cortes nesses subsídios contribuiriam para maior competitividade das exportações brasileiras e gerariam oportunidades para o crescimento do agronegócio.In the forums of multilateral negotiations of the World Trade Organization (WTO there has been a strong debate which tries to eliminate the agricultural subventions in the developed countries. However, the United States has increased the amount of these subsidies causing distortions in the world agricultural trade. Therefore, the purpose of this research has been to evaluate these American subsidies impacts (Loan Deficiency Payments given between 2002 and 2007 upon the Brazilian agribusiness growth. The findings allow to deduce that the reduction of the subsidies in the United States might promote the growth of the Brazilian agribusiness production and might produce trade surplus in the trade balance in this sector as well as the growth of both exports and imports. Hence the cuts in these subsidies would contribute to a bigger competitiveness of the Brazilian exports and would generate opportunities to the agribusiness growth.

  13. Inferências sobre o calendário agrícola a partir de perfis temporais de NDVI/MODIS

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    Denise Cybis Fontana

    2015-01-01

    Full Text Available Um dos maiores desafios para a modelagem de rendimentos de grãos, no contexto das estimativas de safras feitas de forma operacional para grandes áreas, está relacionado à identificação no tempo dos períodos em que as culturas anuais apresentam maior suscetibilidade a estresses ambientais. Para a cultura da soja, cultivada no período de primavera-verão no sul do Brasil, o principal fator de risco é a ocorrência de estresse hídrico no florescimento e enchimento de grãos. Esses subperíodos ocorrem em períodos distintos ao longo da região de produção como consequência de práticas de manejo diferenciadas dos produtores. Este trabalho teve como objetivo relacionar o calendário agrícola da cultura da soja a perfis temporais do índice de vegetação por diferença normalizada (NDVI/MODIS, com intuito de apresentar/validar uma tecnologia de baixo custo e adequada acurácia para fins de monitoramento e previsão de safras. Para tanto, foram analisados os dados de calendário agrícola (subperíodos de floração, enchimento de grãos e maturação da cultura da soja em regionais da EMATER (RS e imagens NDVI do sensor MODIS. Os resultados mostraram que os perfis temporais de NDVI permitem acompanhar a evolução temporal da biomassa da cultura da soja e determinar a ocorrência dos subperíodos do ciclo. As diferenças no valor do NDVI entre safras, regionais e subperíodos do ciclo da cultura demonstram a sensibilidade deste índice em detectar as respostas das plantas de soja às condições ambientais. Como consequência dos dados de NDVI serem gerados a partir das imagens MODIS, é possível a espacialização da informação acerca dos subperíodos para todas as safras e em todo o Estado, o que permite maior detalhamento temporal e espacial comparativamente à atual disponibilidade dos dados.

  14. The scientific production of Italian agricultural engineers: a bibliometric network analysis concerning the scientific sector AGR/10 Rural buildings and agro-forestry territory

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    Andrea De Montis

    2017-03-01

    Full Text Available According to a worldwide well-known attitude, also in Italy, the assessment of scientific production in the last decades has been progressively based on the analysis of the impact through bibliometric variables. Various data sets, such as Scopus by Elsevier and Web of Science by Thomson Reuters, are designed and maintained to index a steadily increasing range of essays: mostly journal articles, book chapters, and conference proceedings. The indexing relays on the capacity to evaluate and update specific impact measures by keeping track of the citations representing the relations between the essays. The related opportunity to interpret bibliographic systems as research and development (R&D networks attracted the interest of scientists operating, beyond the field of bibliometric analysis, in the realm of social networking. Network analysis belongs to mechanical statistics and is able to make sense of interconnected systems including very large sets of nodes and links. In this paper, we present a network approach to the review of the scientific production in the time period January, 2003-June, 2016 of Italian agricultural engineers, namely scientists belonging to the Italian ministerial scientific disciplinary sector AGR/10 - rural buildings and agro-forestry territory. Starting from 238 articles indexed in the Web of Knowledge database and published by 87 AGR/10 scholars, we apply four network analysis approaches to the study of the citations among articles, the most influential journals and topics, the co-authorship, the most favourite keywords with their evolution in time, and the communities’ pattern. We discover that Italian agricultural engineers are interlaced in a sparse network with a still limited tendency toward citing each other and are inclined to team up in established research groups based on a single university. As for the dualism between rural buildings and territory, we document on a relevant expansion of the issues related to

  15. Efecto de la temperatura sobre coloides de suelos agrícolas mediante dispersión dinámica de la luz

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    Túlio Armando Lerma

    2015-12-01

    Full Text Available La materia orgánica y la fracción coloidal son los principales componentes edafológicos que se ven afectados por la quema indiscriminada de los matorrales. En consecuencia, por acción de las altas temperaturas se produce un deterioro de la estructura, pérdida de la capacidad de intercambio catiónico (CIC y disminución de la fertilidad de los suelos. Por otro lado, se ha planteado el uso de tratamiento térmico in situ como estrategia de cimentación de suelos arcillosos en la construcción de obras civiles. Sin embargo, el efecto de la temperatura sobre la fracción coloidal sólo se ha evaluado frente a propiedades mecánicas; pocos estudios en relación a propiedades de importancia agrícola como la CIC, la estructura y la susceptibilidad a la erosión han sido realizados. El objetivo del presente trabajo fue estudiar mediante dispersión dinámica de la luz (DLS el efecto de la temperatura sobre la fracción coloidal de suelos agrícolas. Para ello se recolectaron y caracterizaron dos muestras de suelos procedentes de los departamentos de Córdoba y Valle del Cauca. La fracción coloidal fue extraída mediante una variante del método de Bouyoucos y sometida a diferentes tratamientos térmicos (desde 150 a 550 °C. Las muestras se caracterizaron por análisis elemental, FT-IR, DLS y se evaluó su CIC. Se concluyó que las propiedades de la fracción coloidal son fuertemente alteradas por efecto de la temperatura, además de evidenciarse una disminución de la CIC (desde 76 a 35 y desde 103 a 26 cmol(+/kg de suelo, el incremento del tamaño de partícula (desde 639 ± 165 a 1250 ± 435 y 606 ± 102 a 1540 ± 320 para S-Córdoba y S-Valle, respectivamente así como la eliminación de la materia orgánica.

  16. Uso do solo na zona ripária de bacias agrícolas de pequeno a médio porte

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    Adilson Pinheiro

    2011-12-01

    Full Text Available As zonas ripárias situam-se às margens dos sistemas de drenagens de águas superficiais, afetando processos hidrológicos. O Código Florestal Brasileiro estabelece um afastamento mínimo ao longo dos cursos de águas, considerado como área de preservação permanente. Este trabalho objetivou determinar a distribuição do uso do solo em bacias agrícolas com várias dimensões para diferentes afastamentos em relação ao sistema de drenagem de águas superficiais. A metodologia utilizada compreendeu o uso de imagens do satélite SPOT-5, para classificação do uso de solo em seis bacias com áreas variando de 14 a 600 km². A precisão da classificação foi determinada pela acuracidade e o nível de acerto, determinado pelo coeficiente Kappa. A partir do sistema de drenagem foram traçadas linhas paralelas aos cursos de águas, denominados buffers, com afastamento das margens de 20, 30, 50, 100 e 200 m. Em cada buffer foi determinada a distribuição da ocupação do uso do solo. Os valores obtidos com a classificação indicaram acerto com coeficiente Kappa médio de 0,96. Os temas classificados em todas as imagens apresentaram boa acuracidade, com valores maiores que 96%. Os resultados apontaram que o uso da terra predominante em todas as bacias é a mata nativa com valores médios de 46,8%, seguida de culturas agrícolas com 24,7% e pastagens com 21,7%. As áreas de matas nativas apresentavam tendência de redução à medida que se afastavam dos cursos de água, enquanto os reflorestamentos tendiam a aumentar o percentual da área ocupada com o afastamento das margens dos rios.

  17. Mitigación de daños provocados por fauna silvestre en cultivos agrícolas en un bosque montano de Bolivia

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    Eddy Pérez L.

    2014-12-01

    Full Text Available El daño causado por fauna silvestre en cultivos agrícolas es una de las causas principales de conflicto dentro y fuera de áreas protegidas. Para un adecuado manejo del conflicto se requieren evaluaciones del daño y de la aplicación de distintos métodos de mitigación. El objetivo del trabajo fue evaluar la efectividad de prácticas agroculturales y cacería de control, para reducir daños por vertebrados silvestres en cultivos agrícolas anuales en el PN ANMI Cotapata. Se trabajó en siete parcelas con prácticas agroculturales, cuatro parcelas con cacería de control y cinco parcelas control, registrándose el tipo y densidad de cultivo, frecuencia de visitas de especies dañinas a huelleros, plantación perdida, especies responsables y biomasa de cosecha. Los resultados muestran que las especies más frecuentes fueron: Dasyprocta sp. y Dasypus novemcinctus, siendo estas 1.6 veces más frecuentes en parcelas con prácticas agroculturales. En promedio se perdió 7.3% de la plantación en parcelas agroculturales, 4.6% en parcelas sujetas a cacería de control, y 27.6% en parcelas control. Las principales especies responsables de las pérdidas fueron: P. tajacu, seguido por Dasyprocta sp. y S. apella. A través de estas estrategias de manejo, redujo las pérdidas en >50%, con lo cual se considera que los métodos puestos a prueba son útiles y se recomienda utilizarlos a gran escala con la consideración de que podría ser necesario innovar cada cierto tiempo, pues los animales silvestres tienden a acostumbrarse a los métodos de ahuyentamiento en ejecución.

  18. Levantamento pedológico da estação experimental de Pindamonhangaba A soil survey of the Pindamonhangaba agr. Exp. Sta

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    Alfredo Küpper

    1960-01-01

    Full Text Available No presente trabalho são estudados, classificados e delimitados os solos da Estação Experimental de Pindamonhangaba. Êsse campo experimental possui uma área de 226 hectares, ou 93,9 alqueires paulistas, dedicando-se a pesquisas agrícolas. Os solos estão classificados em séries monotípicas ou tipos de solo, grande grupo, subordem e ordem, segundo a classificação climática. Acompanham cada série descrições morfológica e genética, bem como principais propriedades físicas e químicas. A fertilidade foi analisada somente pelas propriedades químicas de amostras compostas, colhidas em locais diversos dentro da Estação Os solos zonais, da subordem Latossolo, de boa drenagem, compreendem as séries Pinhão, Pinda, Polêmica e Ponte Alta, e os moderadamente drenados estão definidos pelas séries Guatemala e Gleba. Na categoria de intrazonais são encontrados os grandes grupos Glei Pouco Húmico (série Mosqueada e o Glei Húmico (série Estação. A eerie Dourada é a única que se enquadra no grande grupo Aluvião, da ordem azonal.A detailed soil survey of lhe Paraíba Valley (Taubaté basin is being carried on as a cooperative project between the Instituto Agronômico, Campinas, and the Serviço do Vale do Paraíba. As a part of this project, a soil survey of the Pindamonhangaba Agr, Exp. Sta. (226 hectares was made, the results of which are reported in this paper. The soils were classified in monotype series or soil types, Great Soil Group, sub-order, and order, according to the climatic classification. The fertility problems were studied on the basis of composile soil samples several site of the slatian. The zonal soils belong to the sub-order Latosol and were defined in soil types Pinhão, Pinda. Polêmica, and Ponte Alta, as well drained soils, and Guatemala and Gleba as moderately drained ones. As intraional soils was the Mosqueada series present, defined as Low Humíc Gley and Estação Series as Humic Gley. The Dourada

  19. Caracterização do mercado de fretes rodoviários para produtos agrícolas Characterization of the highway freight market for agricultural products

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    Marcelo Gimenes Soares

    1997-08-01

    Full Text Available O mercado de frete rodoviário no Brasil não sofre nenhum tipo de controle governamental, significando que os preços são formados a partir da negociação direta entre a oferta e a procura pelo serviço. Os transportadores não estão, necessariamente, atualizados sobre todas as variáveis de seu custo para estarem aptos a negociar com os demandantes. Tais demandantes, por outro lado, podem desempenhar maior poder de negociação para obter descontos no valor do frete. Tendo em vista o aprimoramento da qualidade das informações sobre fretes, tanto para ofertantes quanto demandantes pelo serviço de transporte, foi realizado levantamento de valores para produtos agrícolas selecionados, assim como identificadas as principais características do escoamento rodoviário de cargas agrícolas. Dessa forma, ficou evidenciada a diferenciação do valor do frete de acordo com o tipo de produto e verificou-se que a estrutura do mercado de frete para granéis sólidos (açúcar, milho, soja e farelo de soja é bastante distinta, mais pulverizada e talvez menos profissional que a estrutura observada para os granéis líquidos estudados (suco de laranja e óleo de soja.The Brazilian highway freight market is subject to no sort of government control, meaning that the prices are formed through free negotiation between supply and demand of the transport service. Carriers have to be updated on every variable incorporated in costs to be fit for negotiating with demanders. These demanders, except under certain very specific circumstances, have performed higher negotiation power and exerted quite strong pressure to obtain freight discounts. Taking into consideration the accomplishment of the quality of freight information, for both supply and demand sides of the transportation service, data for selected agricultural commodities were collected, as well as the identification of the main characteristics of the road haulage. The difference in the freight values

  20. AGR-2 Data Qualification Report for ATR Cycles 151B-2, 152A, 152B, 153A, 153B and 154A

    Energy Technology Data Exchange (ETDEWEB)

    Binh T. Pham; Jeffrey J. Einerson

    2013-09-01

    This report documents the data qualification status of AGR-2 fuel irradiation experimental data from Advanced Test Reactor (ATR) Cycles 152A, 152B, 153A, 153B, and 154A, as recorded in the Nuclear Data Management and Analysis System (NDMAS). The AGR-2 data streams addressed include thermocouple (TC) temperatures, sweep gas data (flow rate, pressure, and moisture content), and fission product monitoring system (FPMS) data for each of the six capsules in the experiment. A total of 13,400,520 every minute instantaneous TC and sweep gas data records were received and processed by NDMAS for this period. Of these data, 8,911,791 records (66.5% of the total) were determined to be Qualified based on NDMAS accuracy testing and data validity assessment. For temperature, there were 4,266,081 records (74% of the total TC data) that were Failed due to TC instrument failures. For sweep gas flows, there were 222,648 gas flow records (2.91% of the flow data) that were Failed. The inlet gas flow failures due to gas flow cross-talk and leakage problems that occurred after Cycle 150A were corrected by using the same gas mixture in all six capsules and the Leadout. For FPMS data, NDMAS received and processed preliminary release rate and release-to-birth rate ratio (R/B) data for three reactor cycles (Cycles 149B, 150B, and 151A) . This data consists of 45,983 release rate records and 45,235 R/B records for the 12 radionuclides reported. The qualification status of these FPMS data has been set to In Process until receipt of Quality Assurance-approved data generator reports. All of the above data have been processed and tested using a SAS®-based enterprise application software system, stored in a secure Structured Query Language database, made available on the NDMAS Web portal (http://ndmas.inl.gov), and approved by the INL STIM for release to both internal and appropriate external Very High Temperature Reactor Program participants.

  1. Economic analysis of agricultural enterprises in Turkey according to their level of success Análise econômica de empresas agrícolas na Turquia de acordo com seu nível de sucesso

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    Halil Kizilaslan

    2009-04-01

    Full Text Available In this study, agricultural enterprises in Turhal, Tokat were grouped based on their degree of success, their structural characteristics have been identified and their outcomes of activities discussed. The objective of the study was to determine the aspects that render successful agricultural enterprises different from other agricultural enterprises. The point to be achieved through the study is to assist agricultural enterprises with a more effective utilization of existing means in order to help them to develop. Data has been collected from 71 agricultural enterprises, which have been determined by Neyman's Method that is a stratified sampling method, via questionnaires. The Criterion of Agricultural Income Per Enterprise Land Decar has been applied for the classification of the enterprises according to their level of success. When the agricultural income was sufficiently examined in the enterprises, moderate successful and unsuccessful enterprises cannot obtain agricultural income to meet family labor force cost. Their agricultural level is quite below the sum of the family labour wage equivalent and the real interest of the equivalent capital. Therefore, the agricultural income of the examined enterprises is considered insufficient. The rate of the net product to the active capital is 3.45% in successful enterprises, 0.57% in those with moderate success, and for the unsuccessful ones, it has a negative value of -2.22%. This ratio for successful enterprises is close to 5%. Accordingly, the successful enterprises work more efficiently in comparison to the other enterprise groups.Neste estudo, empresas agrícolas de Turhal, Tokat foram agrupadas com base em seu grau de sucesso, suas características foram identificadas e seus resultados de atividades discutidos. O objetivo do estudo é determinar os aspectos que diferenciam empresas agrícolas de sucesso das demais. O ponto a ser alcançado pelo estudo é assistir as empresas agrícolas com um

  2. A participação do poder legislativo na elaboração de políticas públicas para o setor agrícola (2003-2010)

    OpenAIRE

    Lopes, Fábio Luiz Duarte

    2013-01-01

    Resumo: Esta dissertação pretende discutir as ações do Poder Legislativo brasileiro na definição das políticas do setor agrícola/agrário. A pesquisa foi realizada mediante a análise de 330 proposições de lei de autoria do Poder Executivo e do Poder Legislativo, apresentadas entre 2003 e 2010. Por meio de método quantitativo e com ênfase no Legislativo procurou-se analisar a participação dos partidos e dos poderes na autoria das proposições e durante a tramitação dos projetos de lei no Congres...

  3. Diversificação agrícola em localidade rural do Sul do Brasil: reflexões e alternativas de cumprimento da Convenção-Quadro para o controle do tabaco

    OpenAIRE

    Riquinho,Deise Lisboa; Hennington,Élida Azevedo

    2014-01-01

    A diversificação agrícola em áreas de cultivo do tabaco é uma das propostas da Convenção-Quadro, considerada o primeiro tratado internacional de saúde pública da Organização Mundial da Saúde. O objetivo deste estudo é evidenciar e discutir as dificuldades e potencialidades referentes à diversificação agrícola e substituição ao cultivo do tabaco entre representantes do Estado, de organizações da sociedade civil e da própria indústria, em região produtora do Sul do Br...

  4. El CITA y la empresa SONEA Ingeniería y Medio Ambiente colaboran para mejorar la gestión agrícola mediante el uso de drones

    OpenAIRE

    Area de Información, Documentación y Cultura Científica. Centro de Investigación y Tecnología Agroalimentaria de Aragón

    2015-01-01

    El Centro de Investigación y Tecnología Agroalimentaria de Aragón (CITA), organismo adscrito al Departamento de Industria e Innovación ha firmado un convenio con la empresa SONEA Ingeniería y Medio Ambiente, para desarrollar productos y servicios derivados de la teledetección aérea para mejorar la gestión agrícola

  5. Análise em laboratório da redução da evaporação de gotículas para pulverizações agrícolas

    OpenAIRE

    Corrêa, Hermes Geraldo; Maziero,José Valdemar Gonzalez

    1980-01-01

    Estudou-se a evaporação utilizando produtos químicos recomendados para controle do fenômeno, sendo apresentadas técnicas que permitem acompanhar a evaporação das misturas com base aquosa. Os resultados interessam às pulverizações terrestres de defensivos na agricultura, com aparelhos do tipo canhão, e especialmente aquelas realizadas com aviões agrícolas.

  6. Metodología de cálculo y factores que afectan el coeficiente de fricción externa en los pares tribológicos de la maquinaria agrícola

    Directory of Open Access Journals (Sweden)

    Alberto Rodríguez Leyva

    2007-01-01

    por las propiedades mecánicas de los elementos rozantes y de la selección del proceso de maquinado para obtener la rugosidad superficial requerida, lo cual incide significativamente en la eficiencia y la fiabilidad de las máquinas agrícolas así como en el consumo de combustible y en el grado de contaminación del medio ambiente.

  7. Energy and economic evaluation of the cotton agr o-ecosystem: a boarding between family systems of Paraguay and Brazil productions; Avaliacao energetica e economica do agroecossistema algodao: uma abordagem entre sistemas familiares de producao do Paraguai e Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Romero, Maria Gloria Cabrera [Pos-graduacao em Agronomia - Energia na Agricultura, FCA/UNESP, Botucatu, SP (Brazil)], e-mails: gloriac@fca.unesp.br, ayacabrera@hotmail.com; Bueno, Osmar de Carvalho; Esperancini, Maura Seiko Sutsui [Dept. de Gestao e Tecnologia Agroindustrial, FCA/UNESP, Botucatu, SP (Brazil)], e-mail: osmar@fca.unesp.br

    2011-07-01

    The objective of this work was to evaluate the energy and economic efficiency indexes per unit of cotton agr o-ecosystem area in family production systems of Paraguay and Brazil; and, to establish a relationship between the energy and economic. Typologies presented by the Program to Support Small Cotton Holdings (Paraguay), and by the National Program for Strengthening Family Agriculture (Brazil). Family systems of the two countries were identified; these are located from Paraguay (San Juan-Ca) and from Brazil (Le me-Sp). To construct the energy expenditure structure of the cotton agr o-ecosystem, as well as to assess the economic efficiency, the mean values obtained were considered, when they presented similarities in production systems and they were within the typology proposed in this study. From the technical itinerary observed the Paraguayan agr o-ecosystem depended (fossil fuel 56.76%) and industrial source (35.99%). Thus, the energy balance of the agricultural stage was established, which attained a value of 17,740.69 MJ ha{sup -1}; an energy efficiency of 5.28, and a cultural efficiency of 3.04. The Brazilian agr o-ecosystem depended on energy from industrial source (insecticides 39.82%) and from fossil fuel (33.59%); it reached an energy balance of 19,547.88 MJ ha{sup -1}; an energy efficiency of 2.12, and a cultural efficiency index of 0.71. In the economic and energy indicator ratio, with regard to the months referring to the harvest time, that is to say, March, April, and May, the maximum economic efficiency indicator of paraguay was attained in the month of May (1,00), and from Brazil in the month of May (1,71). Both production systems analyzed were presented efficient, however, dependent of external circumstances and non-renewable energy sources. (author)

  8. Avaliação económica de tarifas de água no uso agrícola: um estudo de caso no Sul de Portugal

    Directory of Open Access Journals (Sweden)

    Rui Fragoso

    2009-09-01

    Full Text Available Este artigo avalia os efeitos de políticas de tarifas da água no uso agrícola, em termos do consumo de água, do aproveitamento das áreas beneficiadas com regadio, do rendimento do produtor agrícola, da recuperação dos custos com a água e do desenvolvimento agrícola. A metodologia utilizada baseia-se na elaboração de um modelo de programação matemática multiperíodo, adaptado às características específicas de uma empresa agrícola do Sul de Portugal. Foram analisadas a tarifa fixa por área beneficiada, a tarifa volumétrica por metro cúbico de água consumida, a tarifa binómica e a tarifa progressiva. Para as simulações, foram considerados um cenário produtivo tradicional e um cenário produtivo alternativo, em que são introduzidas culturas de valor acrescentado.This paper evaluates the effects of water tariffs in irrigation, in terms of water consumption, land irrigated, farm income, water cost recovery and agricultural investment. The methodology is based on a multiperiod mathematical programming model, which was applied to the specific characteristics of a representative farm in southern Portugal. The main aspects analyzed were: the fix tariff per area benefited, the volumetric tariff per cubic meter of water consumed, the mix tariff and the increasing block tariff. For the simulations, it was considered a traditional productive scenario and an alternative scenario, which include value added crops.

  9. Tecnologias da Web Semântica para a recuperação de dados agrícolas: um estudo sobre o International Information System of the Agricultural Science and Technology (AGRIS)

    National Research Council Canada - National Science Library

    Fábio Mosso Moreira; Ricardo César Gonçalves Sant'Ana; José Eduardo Santarem Segundo; Silvana Aparecida Borsetti Gregorio Vidotti

    2015-01-01

    ... as tecnologias semânticas utilizadas no International Information System of the Agricultural Science and Technology - AGRIS, e apontar o papel destas no processo de recuperação de dados e informações agrícolas. Por meio de uma pesquisa bibliográfica e uma análise exploratória no portal web do AGRIS, foram descritas as tecnologias utili...

  10. Aislamiento e identificación de diez cepas bacterianas desnitrificantes a partir de un suelo agrícola contaminado con abonos nitrogenados proveniente de una finca productora de cebolla en la Laguna de Tota, Boyacá, Colombia

    OpenAIRE

    ostos ortiz, olga lucia; Benavides López de Mesa, Joaquín; Quintero, Gladys

    2006-01-01

    Este articulo presenta los resultados de la versatilidad adaptativa y tolerancia de una consorcio bacteriano constituido por 10 cepas bacterianas endémicas de un suelo agrícola contaminado, proveniente de una finca productora de cebolla ubicada en la laguna de Tota en Aquitania, Boyacá, Colombia, expuesto al uso incontrolado de fertilizantes nitrogenados. La consorcio bacteriano aislado del suelo está conformado por: Bacillus megaterium, Bacillus licheniformis, Pseudomonas stutzeri, Acinetoba...

  11. El espacio rural portugués en el marco de la política agrícola común europea: algunas implicaciones para la agricultura familiar

    Directory of Open Access Journals (Sweden)

    Diosey Ramón Lugo-Morín

    2012-01-01

    Full Text Available La política agrícola europea ha estado enfocada a la estabilización de los precios y la intervención de los mercados con una fuerte protección traducida en incentivos y subvenciones al sector agropecuario, así como introducir medidas con lógica territorial y multisectorial. Esta política ha originado una reconfiguración y recomposición social en el espacio rural portugués, que ha afectado particularmente a la agricultura familiar. En este estudio se examina el acompañamiento institucional en el marco de la política agrícola común europea y su efecto en las estrategias de reproducción de las pequeñas explotaciones portuguesas. Se concluye que la instrumentación de la política agrícola europea en el espacio rural portugués ha tenido efectos negativos en las pequeñas explotaciones originando a su interior una reformulación de sus estrategias de reproducción.

  12. Análisis de redes sociales para catalizar la innovación agrícola: de los vínculos directos a la integración y radialidad

    Directory of Open Access Journals (Sweden)

    Norman Aguilar-Gallegos

    2016-07-01

    Full Text Available Se analizan los efectos de las interacciones, directas e indirectas, entre agricultores y otros actores relevantes en el intercambio de información y conocimiento para la innovación agrícola. Los datos se obtuvieron al preguntar a 120 agricultores «¿de quién aprende y/o a quién recurre para obtener información o conocimiento de cuestiones técnicas y productivas en torno a su unidad de producción?». Se emplean indicadores del análisis de redes sociales para proponer lineamientos que permitan catalizar la innovación agrícola. Los resultados confirman la importancia de los vínculos indirectos, pues estos permiten que los agricultores alcancen mejor información de fuentes externas. Se recomienda que los programas encaminados a promover la innovación agrícola consideren la interacción preexistente en las redes de los agricultores.

  13. Desmatamento Recente nos Estados da Amazônia Legal: uma análise da contribuição dos preços agrícolas e das políticas governamentais

    Directory of Open Access Journals (Sweden)

    Marcelo Dias Paes Ferreira

    2015-03-01

    Full Text Available O objetivo desse trabalho foi analisar como os preços agrícolas e as políticas públicas afetaram o desmatamento nos estados da Amazônia Legal brasileira no período de 1999 a 2011. Para esse fim, foram utilizados dados estaduais em um modelo de dados em painel e uma metodologia de análise de efeitos líquidos de políticas sobre o desmatamento. Os resultados indicam que o desmatamento está mais relacionado aos preços agrícolas do que às variáveis de políticas associados ao crédito rural e gastos com transporte e agricultura. Entretanto, os resultados parecem indicar que políticas recentes de fiscalização mais focadas, como embargos de comercialização de áreas desmatadas ilegalmente e restrição de crédito para áreas irregulares ou que não cumprem a legislação ambiental, podem ter sido mais efetivas para a redução do desmatamento no estado de Mato Grosso. Sendo assim, concluiu-se que o desmatamento na Amazônia Legal é influenciado tanto pela variação dos preços agrícolas quanto pelas políticas governamentais.

  14. Verificação de requisitos de segurança de tratores agrícolas em alguns municípios do estado de São Paulo

    Directory of Open Access Journals (Sweden)

    Ila Maria Corrêa

    Full Text Available Um levantamento de informações foi realizado com o objetivo de avaliar as condições de segurança de tratores agrícolas novos e usados em alguns municípios do estado de São Paulo. Foram avaliados 487 tratores em uso em 270 propriedades agrícolas do estado de São Paulo e 31 tratores novos disponíveis em revendas e em exposição em feiras agrícolas, sendo inspecionados alguns requisitos de segurança relativos a posto de operação, acesso, comandos, proteção de partes móveis, disponibilização de avisos contra riscos de acidentes e requisitos necessários para tráfego em rodovias, previstos em documentos normativos nacionais e/ou internacionais. Verificou-se que os tratores em uso no campo não favorecem a segurança e o conforto do operador, enquanto que os tratores novos mostram tendência de atendimento aos requisitos de segurança e conforto, principalmente aqueles relacionados ao posto de operação e à proteção de partes ativas.

  15. Análisis de redes sociales para catalizar la innovación agrícola: de los vínculos directos a la integración y radialidad

    Directory of Open Access Journals (Sweden)

    Norman Aguilar-Gallegos

    2016-01-01

    Full Text Available Se analizan los efectos de las interacciones, directas e indirectas, entre agricultores y otros actores relevan- tes en el intercambio de información y conocimiento para la innovación agrícola. Los datos se obtuvieron al preguntar a 120 agricultores « ¿de quién aprende y/o a quién recurre para obtener información o conocimiento de cuestiones técnicas y productivas en torno a su unidad de producción? » . Se emplean indicadores del análisis de redes sociales para proponer lineamientos que permitan catalizar la innova- ción agrícola. Los resultados confirman la importancia de los vínculos indirectos, pues estos permiten que los agricultores alcancen mejor información de fuentes externas. Se recomienda que los programas encaminados a promover la innovación agrícola consideren la interacción preexistente en las redes de los agricultores.

  16. Evaluación de riesgos en sistemas agrícolas asociados a la utilización de plaguicidas en el Municipio de Kukra Hill, Nicaragua, Centroamérica

    Directory of Open Access Journals (Sweden)

    Juan Asdrúbal Flores-Pacheco

    2013-06-01

    Full Text Available La presente investigación pretende identificar y tipificar los riesgos humanos y ambientales asociados a la utilización de plaguicidas en las actividades agrícolas en el municipio de Kukra Hill, Región Autónoma del Atlántico Sur (RAAS, Nicaragua. Se trabajó desde la evaluación de sus concentraciones en suelos y escorrentías superficiales en áreas de uso agrícola, lo que es complementado con una investigación de las condiciones de seguridad laboral, tanto preventiva como correctiva, que los agro-aplicadores realizan en sus labores diarias. Se logró determinar que existen presencia y concentración de moléculas de plaguicida en concentraciones por debajo de los niveles de detección permisibles según valores guías canadienses de calidad de suelo de uso agrícola para la protección ambiental y salud humana. Se han incluido los testimonios de técnicos extensionistas privados y de instituciones gubernamentales. Los resultados muestran un escaso uso de protecciones personales y una importante exposición laboral y extra-laboral a pesticidas.

  17. Evaluación del funcionamiento las estructuras de protección contra volcaduras (ROPS montadas en tractores agrícolas que se comercializan en México

    Directory of Open Access Journals (Sweden)

    Marco Antonio Audelo Benítez

    2013-01-01

    Full Text Available El aplastamiento de los operadores de tractores es el principal riesgo de accidente cuando se utilizan máquinas agrícolas. Las estructuras de protección son una alternativa para prevenir que el operador sufra un daño al momento de que se presente una volcadura. El objetivo de este trabajo es evaluar el funcionamiento de éstas estructuras montadas en tractores agrícolas que se comercializan en México. La metodología utilizada se basa en la norma mexicana NMX-O-181-SCFI-2003 que a su vez es el código 4 de la OECD. Las pruebas se realizaron en el Labo- ratorio de Pruebas del Centro Nacional de Estandarización de Maquinara Agrícola (CENEMA perteneciente al INIFAP. En total se probaron 50 estructuras de protección, montadas en 107 modelos de tractores. De las estructuras probadas 13 han sido rechazadas porque no cumplen con el objetivo de proteger la zona de seguridad al momento que se presenta una volcadura. La principal causa del rechazo es la invasión de la zona de seguridad antes de iniciar con la aplicación de las cargas. Esto quiere decir que en la mayoría de los casos no hay un problema de resistencia en las estructuras, el problema es la configuración del tractor probado.

  18. La Migración como Factor de Cambio en el Espacio Agrícola de Localidades Rurales Ubicadas en el Valle de Ixtlán, Michoacán

    Directory of Open Access Journals (Sweden)

    Jesús Gil Méndez

    2008-12-01

    Full Text Available Este artículo describe como es que la migración internacional a Estados Unidos, particularmente de agricultores y gente ligada a la actividad agrícola, se ha convertido en un factor central que está incidiendo de diversos modos en la forma en que los habitantes de las localidades rurales organizan el aprovechamiento de sus recursos agrícolas. A su vez, se pondrá énfasis en los programas de ajuste estructural y de reconversión económica que, sobre todo, desde la década de los ochenta del siglo pasado han impulsado los gobiernos mexicanos, motivando con ello que se intensifique más la migración de origen rural. Así, se abordaran los vínculos que se generan entre la actividad agrícola y migratoria en un contexto de migración intensa y de una agricultura tecnificada. El periodo que se tomó en cuenta para el análisis va desde el inicio de los programas braceros hasta los primeros años del presente siglo en localidades pertenecientes al Municipio de Ixtlán, al noroeste de Michoacán.

  19. La combinación de sistemas agrícolas tradicionales y comerciales, el proceso de conversión en Cruz de Piedra, Estado de México

    Directory of Open Access Journals (Sweden)

    Leonardo Ernesto Márquez Mireles

    2007-01-01

    Full Text Available La comprensión de las relaciones establecidas entre la cultura y la agricultura de una población dedicada al cultivo, ubicada en el ecotono, al sur del volcán Nevado de Toluca, en el Estado de México; genera varias preguntas, entre ellas: ¿Cuáles son las transformaciones que han sufrido la organización social y el trabajo agrícola que permiten combinar un sistema agrícola convencional con un sistema agrícola tradicional? La respuesta a la pregunta se deriva en dos rubros: (1 Para que los campesinos dentro del proceso de conversión tengan dinero para la compra de insumos agroindustriales, este debe ingresar a través de actividades asalariadas o de la migración; (2 La conversión implica desarrollar una agricultura de monocultivos y dejar a un lado la diversidad de cultivos de la agricultura tradicional. Los resultados que se presentan a lo largo de este artículo muestran cómo se realizó esta combinación y cuáles fueron los mecanismos de ajuste social y cultural a su ambiente y al mercado.

  20. Análisis de la situación actual y aplicación de buenas prácticas agrícolas en la producción de cacao ccn 51 de la asociación de trabajadores agrícolas campamento

    OpenAIRE

    Gavilanes Garofalo, Elson Anival

    2016-01-01

    La actual Asociación de trabajadores Agrícolas Autónomos Campamento creada con acuerdo ministerial número 9343 en el año 2008 y en el año 2012 de manos del Sr. Presidente de la República del Ecuador se entregó la respectiva escritura de la tierra a sus socios conjuntamente con otras asociaciones más. Los miembros de esta asociación vienen trabajando las tierras en forma individual el cultivo que mayor área ocupa es el cacao CCN-51, su producción promedio no alcanza los 15 qq/ha./año, la b...