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Sample records for merida yucatan state

  1. Science and stewardship to protect and sustain wilderness values: Ninth World Wilderness Congress symposium; November 6-13, 2009; Merida, Yucatan, Mexico

    Science.gov (United States)

    Alan Watson; Joaquin Murrieta-Saldivar; Brooke McBride

    2011-01-01

    The Ninth World Wilderness Congress (WILD9) met in Merida, Yucatan, Mexico in 2009. The symposium on science and stewardship to protect and sustain wilderness values was the largest of multiple symposia held in conjunction with the Congress. The papers contained in this proceedings were generated at this symposium or submitted by the author or authors for consideration...

  2. Superficial methane emissions from a landfill in Merida, Yucatan, Mexico; Emisiones superficiales de metano en un relleno sanitario en Merida, Yucatan, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Sauri-Riancho, Maria Rosa [Universidad Autonoma de Yucatan, Yucatan (Mexico)]. E-mail: sriancho@uady.mx; Stentiford, Edward I. [University of Leeds (UK)]. E-mail: e.i.stentiford@leeds.ac.uk; Gamboa-Marrufo, Mauricio; Reza-Bacelis, Gabriela; Cahuich-Poot, Nayla; Mendez-Novelo, Roger [Universidad Autonoma de Yucatan, Yucatan (Mexico)]. E-mails: gmarrufo@uady.mx; gabriela.reza@proactiva.com.mx; nayre63@hotmail.com; mnovelo@uady.mx

    2013-07-15

    On worldwide scale, one of the most important anthropogenic methane sources is landfill disposal for solid wastes. The main goal of this work was to quantify methane emissions at one landfill built in Merida, Mexico. This site had venting wells by which a passive control for biogas movement was exerted. At the venting wells, methane concentrations were measured monthly during a 6 months period. Methane surface emission rate was estimated with the close chamber technique. Obtained results indicated that there are both spatial and seasonal variations in biogas composition. The average methane value during the monitoring period was 21.9% (12.7 to 32.5 V/V) and the surface flow rate was in the range of 0 to 6,004 g CH{sub 4} m-2 d-1, with an average value of 1,480 g CH{sub 4} m-2 d-1, which is a high value in respect to these reported in publications. [Spanish] Entre las fuentes antropogenicas mas importantes de metano a escala mundial se encuentra la disposicion final de los residuos solidos. El objetivo de este trabajo fue cuantificar las emisiones de metano provenientes de un relleno sanitario en Merida, Mexico, en el que el movimiento del biogas se controlaba pasivamente utilizando pozos de venteo. Las concentraciones de metano se midieron mensualmente en los pozos de venteo del sitio a lo largo de un periodo de 6 meses. La tasa de emision superficial de metano se determino utilizando la tecnica de camara cerrada. Los resultados indicaron que existen variaciones considerables tanto espaciales como estacionales de la composicion del biogas proveniente de los pozos de venteo con un promedio de concentracion de metano en el sitio, durante todo el periodo de monitoreo, de 21.9% (12.7 a 32.5 V/V). Los flujos superficiales de gas medidos en diversos puntos a lo largo de la superficie del relleno sanitario tuvieron un promedio de 1,480 g CH{sub 4} m-2 d-1, lo que se considero un valor muy alto cuando se comparo con la informacion hallada en la literatura. El intervalo

  3. Body fatness in relation to physical activity and selected socioeconomic parameters of adolescents aged 15-17 years in Merida, Yucatan.

    Science.gov (United States)

    Datta Banik, Sudip; Castillo, Teresa; Rodriguez, Luis; Dickinson, Federico

    2014-01-01

    Increasing rates of overweight and obesity in adolescents are major concerns in many countries, including Mexico. To study anthropometric and body composition characteristics (BCC) and their relations with socioeconomic status (SES), biological history and physical activity (PA) of school-going adolescent boys and girls in the city of Merida, Yucatan, Mexico. In this cross-sectional study, a sample of 321 adolescents (156 boys and 165 girls) aged 15-17 years from public and private schools in Merida, was taken from a study carried out in 2008-2009. Body mass index had significant correlations to BCC (fat mass and fat-free mass). The rate of stunting was higher in girls (18.20%) than in boys (7.69%). Stunted adolescents had higher body fat (%) than normally growing peers. High rates of overweight (boys 26.28%, girls 24.24%) and obesity (boys 10.26%, girls 6.06%) were recorded. SES (parents' age, education and occupation; crowding index in the family; household food expenditure), participants' biological history and PA are related with height and BCC by age and sex. Adolescents with excess weight (overweight + obesity) reported being less physically active. SES and PA were strongly related to growth and body fatness in the studied adolescents.

  4. Blood Feeding Status, Gonotrophic Cycle and Survivorship of Aedes (Stegomyia) aegypti (L.) (Diptera: Culicidae) Caught in Churches from Merida, Yucatan, Mexico.

    Science.gov (United States)

    Baak-Baak, C M; Ulloa-Garcia, A; Cigarroa-Toledo, N; Tzuc Dzul, J C; Machain-Williams, C; Torres-Chable, O M; Navarro, J C; Garcia-Rejon, J E

    2017-12-01

    Blood-feeding status, gonotrophic cycle, and survival rates of Aedes (Stegmyia) aegypti (L.) was investigated in catholic churches from Merida, Yucatan. Female Ae. aegypti were caught using backpack aspirator during 25 consecutive days in rainy (2015) and dry season (2016). Blood-feeding status was determined by external examination of the abdomen and classified as unfed, fed, and gravid. Daily changes in the parous-nulliparous ratio were recorded, and the gonotrophic cycle length was estimated by a time series analysis. Also, was observed the vitellogenesis to monitoring egg maturity. In total, 408 females Ae. aegypti were caught, and there was a significant difference in the number of females collected per season (Z = -6.729, P ≤ 0.05). A great number was caught in the rainy season (n = 329). In the dry season, 79 females were caught, which the fed females were twice greatest than the unfed. The length of gonotrophic cycle was estimated on the base of a high correlation coefficient value appearing every 4 days in rainy at 26.7 ± 1.22°C, and 3 days in dry season at 29.8 ± 1.47°C. The daily survival rate of the Ae. aegypti population was higher in both seasons, 0.94 and 0.93 for the rainy and dry season, respectively. The minimum time estimated for developing mature eggs after blood feeding was similar in both seasons (3.5 days in rainy versus 3.25 days in dry). The measurement of the vectorial capacity of Ae. aegypti in catholic churches could help to understand the dynamics of transmission of arboviruses in sites with high human aggregation.

  5. Host-Feeding Preference of the Mosquito, Culex quinquefasciatus, in Yucatan State, Mexico

    Science.gov (United States)

    Garcia-Rejon, Julian E.; Blitvich, Bradley J.; Farfan-Ale, Jose A.; Loroño-Pino, Maria A.; Chi Chim, Wilberth A.; Flores-Flores, Luis F.; Rosado-Paredes, Elsy; Baak-Baak, Carlos; Perez-Mutul, Jose; Suarez-Solis, Victor; Fernandez-Salas, Ildefonso; Beaty, Barry J.

    2010-01-01

    Studies were conducted to determine the host-feeding preference of Culex quinquefasciatus Say (Diptera: Culicidae) in relation to the availability of human and domestic animals in the city of Merida, Yucatan State, Mexico. Mosquitoes were collected in the backyards of houses using resting wooden boxes. Collections were made five times per week from January to December 2005. DNA was extracted from engorged females and tested by PCR using universal avian- and mammalian-specific primers. DNA extracted from avian-derived blood was further analyzed by PCR using primers that differentiate among the birds of three avian orders: Passeriformes, Columbiformes and Galliformes. PCR products obtained from mammalian-derived blood were subjected to restriction enzyme digestion to differentiate between human-, dog-, cat-, pig-, and horse-derived blood meals. Overall, 82% of engorged mosquitoes had fed on birds, and 18% had fed on mammals. The most frequent vertebrate hosts were Galliformes (47.1%), Passeriformes (23.8%), Columbiformes (11.2%) birds, and dogs (8.8%). The overall human blood index was 6.7%. The overall forage ratio for humans was 0.1, indicating that humans were not a preferred host for Cx. quinquefasciatus in Merida. PMID:20578953

  6. INTERVENCIÓN ARQUEOMAGNÉTICA DEL HORNO DE LA HACIENDA SAN PEDRO CHOLUL (MÉRIDA, YUCATÁN (Archaeomagnetic Dating of a Kiln from the San Pedro Cholul Hacienda (Merida, Yucatan

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    Héctor Hernández Álvarez

    2017-12-01

    Full Text Available En el presente trabajo se reportan los resultados de un estudio arqueomagnético realizado en un horno para la quema de cal encontrado en la hacienda henequenera de San Pedro Cholul, localizada al noroeste de la ciudad de Mérida en el estado de Yucatán, México. La finalidad del estudio es establecer una cronología confiable y analizar las posibles consecuencias sociales, económicas y ambientales de este asentamiento, el cual existió posiblemente desde mediados del siglo XIX hasta los años sesenta del siglo pasado. Para la determinación de la cronología, se utilizó el método de datación arqueomagnética a estructuras pirotecnológicas de estas características. Las muestras estudiadas provienen de rocas y ladrillos del horno y arrojan una edad entre 1835 y 1896, la cual concuerda con la información histórica disponible y se interpreta como el periodo de producción más importante de la región. ENGLISH: This paper presents the results of an archaeomagnetic study carried out on a lime burning kiln at the henequen hacienda of San Pedro Cholul (northwest of the city of Merida in the state of Yucatan, Mexico. The purpose of the study is to establish a reliable chronology and to estimate the possible social, economic and environmental implications of this settlement, which may have existed from the middle of the nineteenth century until the 1960s. Archaeomagnetic dating was carried out on samples obtained from rocks and bricks from the kiln and give an age between 1835 and 1896. This date range agrees with available historical information and is interpreted as the most important production period of the region.

  7. Meat production perspective in Yucatan

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    Victor M. Toledo-Lopez

    2011-12-01

    Full Text Available The evolution of meat production in Mexico during the last decade is the result of the complex interaction between different areas of livestock production and consumers’ preferences, being the former widely influenced by new tendencies and purchasing capacity. In Yucatan, there are two meat product processing plants. Yucatan’s research projects are basically focused to production, handling and genetics. This research is developed in Research Centers like Universidad Autonoma Yucatan’s Ciencias Biologicas Agropecuarias Campus, INIFAP Mococha, Instituto Tecnologico Conkal and Instituto Tecnologoco Merida. Many projects are inter-institutional and others by Cuerpos Academicos inside the institutions. Grants are provided by state, national or international dependencies. In the Instituto Tecnologico Merida research projects are on different animals’ meat quality and novel meat products.

  8. Contributions to improve fallow system in Yucatan State Mexico

    Science.gov (United States)

    Gabriel Uribe Valle; Juan Jiménez-Osornio; Roberto Dzib Echeverría

    2006-01-01

    More than 25 percent of earth warming can be attributes to deforestation practices such as crop rotations performed in southeast part of Mexico. In the Yucatan peninsula 20 percent of staple foods such as maize and beans are produced under slash and burn system. It has been practiced for many centuries by native Mayans however population pressure and food scarcity made...

  9. REMOVAL EFFICIENCY OF ORGANIC MATTER OF PIG SLURRY WITH BIODIGESTERS IN YUCATAN STATE, MEXICO

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    W. Trejo-Lizama

    2014-08-01

    Full Text Available In the intensive pig production in the state of Yucatan, 62 biodigesters were installed in the last 10 years. However, the complexities of the anaerobic biodigestion enclose difficulties to reach the expected efficiency. The objective of the present study was to determine the removal efficiency of the organic matter in pig slurry using biodigesters in the state of Yucatan. There were visited 15 pig farms in the state of Yucatan to interview the farmer about the management of the farm and the waste disposal and to take samples of the influent of the collector of the pig slurry and the effluent of the biodigestor and evaluating the samples by laboratory analysis. The removal values found in the present study were 7 percentage points below the reference value of total volatile solids, which represent the organic matter fraction of the solids treated in the biodigestor. More than the 50 % of the farms evaluated were similar or higher than the parameters of reference. The removal efficiency of the organic matter in the pig slurry by biodigesters in the state of Yucatan is close to the reference values. However complementary treatments are necessary to continue the waste slurry treatment.

  10. Prefeasibility of the project for repowering the Nachi Cocom thermal station in Merida, Yucatan state; Prefactibilidad del proyecto de repotenciacion de la central termoelectrica de Nachi- Cocom, en Merida estado de Yucatan

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Perez, J.L. [Comision Federal de Electricidad (CFE) (Mexico)

    1995-12-31

    This paper presents an alternative to the solution of the more efficient use of energy and for the solution on environmental pollution at a reduced cost, satisfying the electric energy demand with additional capacity three times as much greater than the installed capacity and utilizing evaluation of projects techniques for the prefeasibility analysis of the project. The investment for this type of projects results are feasible and attractive because of the short amortization term. The summary of results is given in Table 4. [Espanol] El presenta trabajo da una alternativa de solucion al uso mas eficiente de la energia y solucion a los problemas de contaminacion ambiental a un costo reducido, satisfaciendo la demanda de energia electrica con capacidad adicional de tres veces mayor a la capacidad instalada. Empleando tecnicas de evaluacion de proyectos para analisis de la prefactibilidad del proyecto. La inversion para este tipo de proyectos resulta factible y atractiva por el corto tiempo de amortizacion. El resumen de los resultados se muestra en la tabla 4.

  11. Seasonal transmission of Leishmania (Leishmania mexicana in the state of Campeche, Yucatan Peninsula, Mexico

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    Andrade-Narvaez Fernando J

    2003-01-01

    Full Text Available In the Yucatan Peninsula, Mexico, localized cutaneous leishmaniasis (LCL caused by Leishmania (Leishmania mexicana is a typical wild zoonosis restricted to the forest, and humans are only accidentally involved. The transmission of L. (L. mexicana has been related to the patient's occupation: "chicleros"(gum collectors and agricultural workers. The objective of this study was to document L. (L. mexicana seasonally of transmission in endemic areas of LCL in the state of Campeche, Yucatan Peninsula, Mexico. The timing of incidence of LCL in humans during 1993-1994, as well as the rate and time of infection in rodents and sand flies between February 1993 and March 1995 were analyzed. Rodents and sand flies were found infected between November and March, when men carried out their field activities and are exposed. Based on results analyzed, it is concluded that L. (L. mexicana in the endemic area of LCL in the state of Campeche, Yucatan Peninsula, Mexico, presents a seasonal transmission restricted to the months of November to March. The knowledge of the timing of the transmission cycle in an endemic area of leishmaniasis is very important because intervention measures on the high-risk focus and population might be restricted.

  12. 1 Sunday November 30, 2008 Merida, Yucatan, Mexico Fiesta ...

    International Development Research Centre (IDRC) Digital Library (Canada)

    Jayne Bergeron

    2008-11-30

    Nov 30, 2008 ... use of agro-chemicals in different agro industries and cultivations, and discuss the challenges related to their regulation ... República, Uruguay) and worked as Chief of the Planning Department of the. Food National Institute in Uruguay ...... restrictions on access to loans. Child food and nutrient consumption.

  13. Intervention on housing of Meridas Historic Center

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    Juan Carlos Mansur

    2017-01-01

    Full Text Available This article deals about the importance of rethink and recover the principle of dwelling as an esential principle of Architecture and Urbanism, that allows to comprehend in a deeper meaning, that the sense and importance of Restauration and Intervention of Meridas Historic City Center implies the recover of habits and customs in dayly life of Merida that used to exist previous the economic and social Modernization that generated a transformation in the way of life and interest of citizens, and with that, the transformation of the shape of Merida and the abandon and deterioration of the Historic City Center.

  14. HYDROGEOLOGY AND CONCEPTUAL MODEL OF THE KARSTIC COASTAL AQUIFER IN NORTHERN YUCATAN STATE, MEXICO

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    Miguel J Villasuso-Pino

    2011-04-01

    Full Text Available The coastal zone of northern Yucatan Peninsula (YP is mainly constituted by Tertiary limestones, covered by Pleistocen limestones, where there exist swamps and estuary systems, locally called “rías”, with mouths connecting them to the sea and hence being a way for an important amount of groundwater to discharge, like in Ría Lagartos and Celestún. These limestones have karstic layers located at depths from 8 to 16 meters below terrain surface.  It is in these layers where groundwater mainly flows toward coast, passing below the sand dune and discharging in the sea in the form of submarine springs which in many cases manifest themselves on the marine surface depending on the hydraulic or piezometric fresh water head. The width of the superficial limestone within this coastal fringe, called “caliche”, varies from 5 to 10 kilometers in the study zone (Chuburna-Progreso-Chicxulub.  Its permeability is extremely low, so it constitutes a confining layer that impedes superficial waters to percolate toward groundwater.  The hydraulic head of the groundwater below this confining layer is over the mean sea level and also over the swamp water level, coastal lagoons and estuaries. There are two important hydrological phenomena that occur in this coastal fringe: 1 There is no recharge to the aquifer (groundwater due to limestone rock outcrops is impermeable or semipermeable; and 2 groundwater pressure is not lost, nor saline interfase is rised if the superficial layer is broken.  The groundwater pollution vulnerability within this coastal fringe is less than that for the superficial saline waters of swamps and estuaries, because of caliche’s low intrinsic permeability that impedes percolation.

  15. CALIDAD DEL SERVICIO DE COMIDA RÁPIDA A PARTIR DE LA PARTICIPACIÓN DEL EMPLEADO DE VANGUARDIA, MUNICIPIO LIBERTADOR, ESTADO MÉRIDA, VENEZUELA | QUALITY OF FAST FOOD SERVICE FROM VANGUARD EMPLOYEE PARTICIPATION, LIBERTADOR MUNICIPALITY, MERIDA STATE, VENEZUELA

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    Marysela Coromoto Morillo Moreno

    2015-11-01

    Full Text Available Currently, the service quality is the biggest distinguishing factor and the most powerful competitive advantage of service companies, where the performance of the human factor is fundamental. For the study of service quality two fundamental props exist: the internal and the external clients. The present investigation analyzes the service quality of fast food businesses from the participation of the avant-garde employee, in the specific case of businesses located in Libertador Municipality of Merida State, Venezuela. For this purpose, the integral model of quality breaches of the service and the scale of Dineserv were applied during the second semester of 2014. In this regards, a representative sample of the population of managers, employees and external customers of fast food businesses was selected, and a survey was applied to each of them. Compliance with the standards of the service employees was verified, as well as the positive correspondence between this performance and the levels of quality of service perceived by the user. To confront the low perception of the performance of the employee, rewards, recognition and multiple and varied stimulus should be implemented in order to motivate for a continuous improvement of the quality of service.

  16. Education, fish consumption, well water, chicken coops, and cooking fires: Using biogeochemistry and ethnography to study exposure of children from Yucatan, Mexico to metals and arsenic.

    Science.gov (United States)

    Arcega-Cabrera, Flor; Fargher, Lane F

    2016-10-15

    Around the world, the nocuous health effects of exposure to environmental contaminants, especially metals and Arsenic, are a growing health concern. This is especially the case in Mexico, where corruption and ineffective political administration are contributing to increasing deterioration in the environment. Importantly, shallow soils and the karstic nature of bedrock in Yucatan, Mexico make the subterranean aquifer especially susceptible to contamination because contaminates are carried to it with little resistance. Given these environmental conditions, we developed a multi/interdisciplinary project to evaluate the impact of metal and Arsenic pollution on a sample of 107 children, ages 6 to 9years, living in the urban areas of Progreso, Merida, and Ticul, in the State of Yucatan using urine and blood samples. In addition, ethnographic research was carried out in the homes of the children that participated in the study to identify potential exposure pathways. This research proved invaluable because the complexity of human social organization, lifestyles, and geographical patterning create an intricate array of exposure pathways that vary across social sectors and geographic space. In the following article, we use nonparametric univariate statistical analysis to reveal potential exposure pathways among sub-populations included in our sample. These analyses show that children from poor/marginal families tend to be exposed to Copper, Lead, and Nickel; whereas, children, from wealthier families, tend to be exposed to Cadmium, Arsenic, and inorganic Copper (Copper Sulfate). Copyright © 2016 Elsevier B.V. All rights reserved.

  17. Representación gráfica del riesgo de mortalidad neonatal en un centro perinatal regional en Mérida, Yucatán, México The graphical display of neonatal mortality risk at a regional perinatal center in Merida, Yucatan, Mexico: The joint effect of birth weight and gestational age

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    Lorenzo Osorno-Covarrubias

    2002-07-01

    Full Text Available Objetivo. Determinar el riesgo de mortalidad neonatal por edad gestacional y el peso al nacer. Material y métodos. Se estudió una cohorte de 19 668 neonatos que egresaron entre el 1 de enero de 1995 y el 31 de octubre de 1999 del Centro Médico Nacional Ignacio García Téllez, del tercer nivel de atención perinatal del Instituto Mexicano del Seguro Social de la Península de Yucatán. Se registraron el peso al nacer, edad gestacional y condición de egreso. Se calculó el riesgo absoluto (RA de mortalidad para cada semana de edad gestacional y grupo de peso. Resultados. El RA de mortalidad observado en neonatos de entre 34 a 44 semanas y peso mayor o igual a 2 250 g fue de 0.4%, de 15% para aquellos de entre 26 a 32 semanas con peso mayor o igual a 1000 g, y de 73% para los de entre las 26 a las 34 semanas, con peso al nacimiento de entre 750 y 1 000 g. Conclusione. El RA de mortalidad neonatal aumentó a menor. edad gestacional y peso. Los datos pueden ser utilizados como valores de referencia para nuestro hospital y para comparación con otros hospitales.Objective. To determine the neonatal mortality risk according to gestational age and birth weight. Material and Methods. The cohort consisted of 19 668 newborns of Centro Médico Nacional (National Medical Center Ignacio García Téllez, a tertiary level healthcare institution of the Instituto Mexicano del Seguro Social (Mexican Institute of Social Security, IMSS of the Yucatan Peninsula. All new-borns discharged from the hospital between January 1 st , 1995 and October 31 st , 1999 were included in the study. Birth weight, gestational age, and conditions upon discharge were recorded. Absolute risk (AR of mortality was calculated for each week-of-gestation- and birth group. Results. Observed AR in newborns 34 to 44 weeks of gestational age and weighing at least 2 250 g was 0.4, while that for those 26 to 32 weeks of gestational age and weighing between 1000 g was 15%. Conclusions. AR of

  18. Education, fish consumption, well water, chicken coops, and cooking fires: Using biogeochemistry and ethnography to study exposure of children from Yucatan, Mexico to metals and arsenic

    International Nuclear Information System (INIS)

    Arcega-Cabrera, Flor; Fargher, Lane F.

    2016-01-01

    Around the world, the nocuous health effects of exposure to environmental contaminants, especially metals and Arsenic, are a growing health concern. This is especially the case in Mexico, where corruption and ineffective political administration are contributing to increasing deterioration in the environment. Importantly, shallow soils and the karstic nature of bedrock in Yucatan, Mexico make the subterranean aquifer especially susceptible to contamination because contaminates are carried to it with little resistance. Given these environmental conditions, we developed a multi/interdisciplinary project to evaluate the impact of metal and Arsenic pollution on a sample of 107 children, ages 6 to 9 years, living in the urban areas of Progreso, Merida, and Ticul, in the State of Yucatan using urine and blood samples. In addition, ethnographic research was carried out in the homes of the children that participated in the study to identify potential exposure pathways. This research proved invaluable because the complexity of human social organization, lifestyles, and geographical patterning create an intricate array of exposure pathways that vary across social sectors and geographic space. In the following article, we use nonparametric univariate statistical analysis to reveal potential exposure pathways among sub-populations included in our sample. These analyses show that children from poor/marginal families tend to be exposed to Copper, Lead, and Nickel; whereas, children, from wealthier families, tend to be exposed to Cadmium, Arsenic, and inorganic Copper (Copper Sulfate). - Highlights: • Metals and Arsenic exposure in children (age 6–9) from Yucatan, Mexico • Quantification of As, Cd, Hg, Pb, Cr, Cu, Ni in Blood and Urine by AAS • Ethnographic research on sociocultural patterns and exposure pathways • Non-parametric statistical analysis • Variation in exposure based on geography, socioeconomic level, and lifestyles

  19. Education, fish consumption, well water, chicken coops, and cooking fires: Using biogeochemistry and ethnography to study exposure of children from Yucatan, Mexico to metals and arsenic

    Energy Technology Data Exchange (ETDEWEB)

    Arcega-Cabrera, Flor [Unidad de Química Sisal, Facultad de Química, Universidad Nacional Autónoma de México (Mexico); Fargher, Lane F., E-mail: fargher@mda.cinvestav.mx [Departamento de Ecología Humana, Centro de Investigación y de Estudios Avanzados del Instituto Politécnico Nacional — Unidad Mérida (Mexico)

    2016-10-15

    Around the world, the nocuous health effects of exposure to environmental contaminants, especially metals and Arsenic, are a growing health concern. This is especially the case in Mexico, where corruption and ineffective political administration are contributing to increasing deterioration in the environment. Importantly, shallow soils and the karstic nature of bedrock in Yucatan, Mexico make the subterranean aquifer especially susceptible to contamination because contaminates are carried to it with little resistance. Given these environmental conditions, we developed a multi/interdisciplinary project to evaluate the impact of metal and Arsenic pollution on a sample of 107 children, ages 6 to 9 years, living in the urban areas of Progreso, Merida, and Ticul, in the State of Yucatan using urine and blood samples. In addition, ethnographic research was carried out in the homes of the children that participated in the study to identify potential exposure pathways. This research proved invaluable because the complexity of human social organization, lifestyles, and geographical patterning create an intricate array of exposure pathways that vary across social sectors and geographic space. In the following article, we use nonparametric univariate statistical analysis to reveal potential exposure pathways among sub-populations included in our sample. These analyses show that children from poor/marginal families tend to be exposed to Copper, Lead, and Nickel; whereas, children, from wealthier families, tend to be exposed to Cadmium, Arsenic, and inorganic Copper (Copper Sulfate). - Highlights: • Metals and Arsenic exposure in children (age 6–9) from Yucatan, Mexico • Quantification of As, Cd, Hg, Pb, Cr, Cu, Ni in Blood and Urine by AAS • Ethnographic research on sociocultural patterns and exposure pathways • Non-parametric statistical analysis • Variation in exposure based on geography, socioeconomic level, and lifestyles.

  20. Genetic data of 15 autosomal STRs (Identifiler kit) of three Mexican Mestizo population samples from the States of Jalisco (West), Puebla (Center), and Yucatan (Southeast).

    Science.gov (United States)

    Rubi-Castellanos, R; Anaya-Palafox, M; Mena-Rojas, E; Bautista-España, D; Muñoz-Valle, J F; Rangel-Villalobos, H

    2009-06-01

    We report autosomal STR data (Identifiler PCR amplification kit) of a total sample of 884 unrelated Mestizos from three different regions of Mexico. The population sample included 309, 313 and 262 individuals from the states of Jalisco (West), Puebla (Center) and Yucatan (Southeast), respectively. Allele distribution and forensic statistical parameters are described. Genotype distribution by locus and two-loci combination was in agreement with Hardy-Weinberg expectations for all 15 STRs. Pairwise comparisons including Mexican populations reported in the literature demonstrated a significant differentiation, principally between North/West with regard to Center/Southeast Mexico. These results increase STR data from previously unreported regions of this country, and constitute a valuable guide in forensic casework for choosing an auxiliary STR database in states where it is not available.

  1. The Merida Initiative: Security-Surveillance Harmonization in Latin America

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    Nelson Arteaga Botello

    2009-10-01

    Full Text Available This work analyses the Merida Initiative, whose objective is to coordinate the information systems used against terrorism, organized crime, and drug and arms trafficking between the United States, Mexico and Central America. This implies the introduction of communication equipment, data bases and surveillance technology, which not only reinforces the security policies of the ‘western hemisphere’, but also consolidates and broadens the spaces of exception in Mexico and Central America, thus eroding their already weakened democratic institutions.  Resumen: La Iniciativa Mérida: la armonización de seguridad y vigilancia en América LatinaEl trabajo analiza la Iniciativa Mérida, que tiene por objetivo coordinar los sistemas de información contra el terrorismo, el crimen organizado, el tráfico de drogas y de armas entre Estados Unidos, México y Centroamérica. Esto implica la introducción de equipos de comunicación, bases de datos y tecnología de vigilancia, las que no sólo refuerzan las políticas de seguridad del ‘hemisferio occidental’, sino también consolidan los espacios de excepción en México y Centroamérica, erosionando las ya debilitadas instituciones democráticas.

  2. CLINICAL INCIDENCE AND FREQUENCY OF LESIONS ASSOCIATED TO PORCINE CIRCOVIRUS TYPE 2 IN PIGS OF A FARM IN THE STATE OF YUCATAN, MEXICO.

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    Jose Leonardo Guillermo Cordero

    2011-01-01

    Full Text Available The objectives of this study were to determine the incidence rate, the cumulative incidence of Postweaning multisystemic wasting syndrome (PMWS and porcine dermatitis nephropathy syndrome (PDNS, and the frequency of macroscopic and microscopic lesions of PMWS and PDNS in pigs in a farm in the state of Yucatan, Mexico. A group of production consisting of 235 pigs was observed from 4 to 22 weeks of life to determine the number of new cases compatible with the PMWS and PDNS. In addition pigs necropsied on the farm that were discarded and with signs consistent with syndromes studied. 80 pigs were studied, the organs inspected during the necropsy were the lungs, lymphonodes, spleen, liver, tonsils, ileum, kidneys and skin, samples of all organs were obtained for histopathological studies. The results were: 14 pigs with signs consistent with syndromes mentioned, 7 with the PMWS and 7 with the PDNS. The cumulate incidence and incidence rate for both syndromes was 0.06 and 0.0034 respectively. 5 pigs died, the lethality rate calculated for PMWS y PDNS was 0.4 and 0.3 respectively. The average time elapsed since the start of the observation period until the pigs sick with the PMWS and PDNS were 13.8 and 16.8 weeks respectively. The principal organ affected were the lymphonodes (100% where the main macroscopic injury was a lymphadenomegaly with diffuse edema (56% and the microscopic was a histiocytic lymphadenitis with lymphoid atrophy (64%

  3. New administrative center of the councils in Merida; Nuevo centro administrativo de las consejerias en Merida

    Energy Technology Data Exchange (ETDEWEB)

    Gamero, E.; Montero, E.

    2008-07-01

    The set of buildings of the new Administrative Center of the Consejerias of the Junta de Extremadura will be located in Merida. The design of the building has been realized bearing aspects of sustainability in mind, like cultural, environmental and the technical one; as well as it has looked for the fulfill diverse criteria of energetic efficiency guaranteeing suitable levels of thermal and visual comfort, acoustic quality and of the internal air. For what it has been necessary to developed strategies like the installation of an air-to-ground heat interchanges, conduits of the Sun, photovoltaic panels, control of the solar radiation and of the contribution of artificial light, air conditioning of high performance, domotics and monitoring. The incorporation of these systems supposes considerable reductions in the energetic consumption, cost of functioning and emissions of CO{sub 2} and greenhouse gases. (Author)

  4. Agent-based modeling of deforestation in southern Yucatan, Mexico, and reforestation in the Midwest United States.

    Science.gov (United States)

    Manson, Steven M; Evans, Tom

    2007-12-26

    We combine mixed-methods research with integrated agent-based modeling to understand land change and economic decision making in the United States and Mexico. This work demonstrates how sustainability science benefits from combining integrated agent-based modeling (which blends methods from the social, ecological, and information sciences) and mixed-methods research (which interleaves multiple approaches ranging from qualitative field research to quantitative laboratory experiments and interpretation of remotely sensed imagery). We test assumptions of utility-maximizing behavior in household-level landscape management in south-central Indiana, linking parcel data, land cover derived from aerial photography, and findings from laboratory experiments. We examine the role of uncertainty and limited information, preferences, differential demographic attributes, and past experience and future time horizons. We also use evolutionary programming to represent bounded rationality in agriculturalist households in the southern Yucatán of Mexico. This approach captures realistic rule of thumb strategies while identifying social and environmental factors in a manner similar to econometric models. These case studies highlight the role of computational models of decision making in land-change contexts and advance our understanding of decision making in general.

  5. Meat production perspective in Yucatan

    OpenAIRE

    Victor M. Toledo-Lopez

    2011-01-01

    The evolution of meat production in Mexico during the last decade is the result of the complex interaction between different areas of livestock production and consumers’ preferences, being the former widely influenced by new tendencies and purchasing capacity. In Yucatan, there are two meat product processing plants. Yucatan’s research projects are basically focused to production, handling and genetics. This research is developed in Research Centers like Universidad Autonoma Yucatan’s Ciencia...

  6. Regional reduction in paleogroundwater discharge and rainfall in the Late Holocene Yucatan Peninsula reconstructed from trace metals in benthic foraminifera

    Science.gov (United States)

    Broach, K. H.; Chapman, B. L.; Paytan, A.; Street, J.

    2017-12-01

    As climate change progresses, droughts are predicted to become more common in regions dominated by seasonal precipitation, a problem compounded where precipitation provides significant freshwater resources. The Yucatan Peninsula relies on rain-recharged groundwater for potable water, and regional development due to tourism will further strain supply. Historical and geochemical evidence suggest extensive droughts harmed Mayan Civilization and may again impact the Yucatan in the near future, but proxies around the Yucatan and Caribbean region are complicated by variability and even opposing interpretations. An integrated rainfall signal is needed to smooth variability and separate local aberrations from long-term regional trends that can be used for risk assessment. Here we present a 5,000 year record of rainfall sourced from a broad swath of the peninsula and recorded as trace metal ratios in the foram Ammonia parkinsoniana. Rainwater percolation across the western peninsula forms a groundwater lens that discharges as brackish springs in our field site Celestun Lagoon resulting in trace metal gradients (Li, B, Sr, Ba, Nd) along the lagoon that oscillate with discharge. Sr/Ca and Ba/Ca ratios in the forams suggest a long-term decrease in spring water discharge for the western Yucatan during the last 2,500 years with notable drops coinciding with known droughts (e.g. 800-950 CE) and more variability on a regional scale to 5,000 years. B/Ca ratios appear to depend on proximity to springs and may respond to low-pH discharge water while Nd/Ca ratios suggest sporadic incursions of seawater into the lagoon, possibly related to severely reduced spring water discharge or large hurricane events. We interpret these results to mean that periods of decreased rainfall broadly affect the western peninsula which may pose problems for large population centers like Merida. Future work will focus on periodicity of such rainfall changes and impact on the ecological environment of

  7. Food intake and nutrition in children 1-4 years of age in Yucatan, Mexico.

    Science.gov (United States)

    Cuanalo de la Cerda, Heriberto E; Ochoa Estrada, Ernesto; Tuz Poot, Felipe R; Datta Banik, Sudip

    2014-01-01

    The National Health and Nutrition Survey 2006 (ENSANUT in Spanish) reported high rates of under-nutrition in children of Yucatan. Is food intake the main cause of under-nutrition in children of the state of Yucatan, Mexico? Identify the primary causes of under-nutrition in pre-school children in Yucatan. A sample of 111 children (59 girls and 52 boys) aged 1-4 years representing Yucatan was taken from a database of ENSANUT 2006 and another national survey, a federal poverty mitigation programme for the state of Yucatan, Mexico entitled "Oportunidades". A human ecology approach together with life history theory was used to analyse anthropometric indices and food intake data from the ENSANUT 2006 and "Oportunidades". Height and weight were significantly correlated to age and total food intake. No correlations were found between age and anthropometric indices or food intake rates. The children in the sample had adequate protein intake but deficient energy intake. No correlation was identified between nutritional status and food intake rates. Pre-schoolers with higher weight-for-height values achieved greater height-for-age. These relationships can be explained by life history theory in that energy intake was used either for maintenance (combating and recovering from infections) or growth. The poor relationship between food intake rates and nutritional status is probably explained by the interaction between high disease incidence and insufficient energy intake. These conditions are endemic in Yucatan due to widespread poor housing, water and sanitation conditions.

  8. Merida Initiative: The Answer for Mexico?

    Science.gov (United States)

    2011-03-15

    St ra te gy R es ea rc h Pr oj ec t MÉRIDA INITIATIVE: THE ANSWER FOR MEXICO ? BY LIEUTENANT COLONEL NANCY M. BOZZER United States Air...DATES COVERED (From - To) 4. TITLE AND SUBTITLE Mérida Initiative: The Answer for Mexico ? 5a. CONTRACT NUMBER 5b. GRANT NUMBER...NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) Professor Daniel Coulter Department of National Security and Strategy Walter Bedell

  9. ISVEE 14 Yucatan 2015 14th Symposium of the International Society for Veterinary Epidemiology and Economics.

    Science.gov (United States)

    de Anda, Jorge Hernández

    2017-02-01

    The 14th Symposium of the International Society for Veterinary Epidemiology and Economics (ISVEE 14) was held in Merida, Yucatan, Mexico during 3-7 November. 2015. The purpose of ISVEE 14 Yucatan 2015 was to provide a global forum for graduate students, postdoctoral fellows, junior and senior investigators, as well as health policymakers to exchange information that can advance the fields of veterinary epidemiology and economics, and other disciplines in the health and social sciences. The main theme of ISVEE 14 was Planning Our Future. Human population growth is predicted to increase nearly 50% to 11 billion by 2050, and climate change and changing land use can have an impact on local and global food systems, interactions among humans, wildlife and domestic animals, as well as local, regional, and global public health alerts. How can we help our systems of education, research, and public policy adapt? Are new veterinary graduates and epidemiology practitioners prepared to become active protagonists in the solution of health issues that affect humans and animal populations in a changing environment? What innovative research is needed to understand and enhance the food systems of the future? What are the expected roles or contributions of veterinarians or epidemiology practitioners on future climate change, food systems, and health? Is our profession or discipline leading One Health initiatives? Are there current or new models that make national veterinary services more efficacious and efficient for disease control and eradication? To help us answer these questions, the organizing committee of ISVEE 14 invited five distinguished keynote speakers to share their vision and innovative ideas on education, technological developments, research, and public policy of our future with a concentration in the following five areas: (i) One Health (Jonna Mazet), (ii) climate change (Bernard Bett), (iii) animal health economics (Jonathan Rushton), (iv) national veterinary services

  10. Population geography of calamity: the sixteenth and seventeenth century Yucatan.

    Science.gov (United States)

    Whitmore, T M

    1996-12-01

    "This historical demography for Yucatan [Mexico] at the time of Spanish contact presents a number of problems. There were multiple Maya-Spaniard contacts before the Spaniards established a continuous presence after the protracted conquest of the Yucatan. The area of Yucatan that was controlled by the Spanish at any one time is not precisely known, and Yucatan offered ¿refuge' areas where the indigenous population could avoid Spanish control and counts. These issues are addressed here by considering different regions of the Yucatan and using a numerical computer simulation to generate new estimates of population that result from migration, warfare, agricultural calamity, and epidemics." excerpt

  11. Racism against the Mayan Population in Yucatan, Mexico: How Current Education Contradicts the Law

    Science.gov (United States)

    Mijangos-Noh, Juan Carlos

    2009-01-01

    The discriminatory situation suffered by the Maya population in the Mexican state of Yucatan is discussed using the concept of neo-racism. Statistical evidence about the school system is presented, along with testimonies of Mayan speakers which uncover a phenomena frequently denied or obliterated by politically correct speeches that actually serve…

  12. Molecular characterization of Yucatan tomato phytoplasma (Group ...

    African Journals Online (AJOL)

    Tomato (Lycopersicon esculentum) is an important vegetable crop in Mexico. Recently, a phytoplasma associated with leaf yellowing and curling, severe stunting and little leaf in tomato plant was identified as Yucatan tomato phytoplasma (16SrIII group). DNAs extracted from tomato leaves with symptoms were examined for ...

  13. Emissions from Biomass Burning in the Yucatan

    Science.gov (United States)

    Yokelson, R.; Crounse, J. D.; DeCarlo, P. F.; Karl, T.; Urbanski, S.; Atlas, E.; Campos, T.; Shinozuka, Y.; Kapustin, V.; Clarke, A. D.; hide

    2009-01-01

    In March 2006 two instrumented aircraft made the first detailed field measurements of biomass burning (BB) emissions in the Northern Hemisphere tropics as part of the MILAGRO project. The aircraft were the National Center for Atmospheric Research C-130 and a University of Montana/US Forest Service Twin Otter. The initial emissions of up to 49 trace gas or particle species were measured from 20 deforestation and crop residue fires on the Yucatan peninsula. This included two trace gases useful as indicaters of BB (HCN and acetonitrile) and several rarely, or never before, measured species: OH, peroxyacetic acid, propanoic acid, hydrogen peroxide, methane sulfonic acid, and sulfuric acid. Crop residue fires emitted more organic acids and ammonia than deforestation fires, but the emissions from the main fire types were otherwise fairly similar. The Yucatan fires emitted unusually amounts of SO2 and particle chloride, likely due to a strong marine influence on the peninsula.

  14. [Comparison of climacteric symptoms among women in Mexico City and women of a Mayan community of Yucatan].

    Science.gov (United States)

    Carranza-Lira, Sebastián; Quiroz González, Byanca Nerea; Alfaro Godinez, Hugo César; May Can, Ana María

    2012-10-01

    to compare the climacteric symptoms between women from Mexico City and those from a Mayan community of the state of Yucatan. In two groups of women, Group I) Spanish-speaking women from Mexico City and Group II) Maya speaking women from the state of Yucatan, 22 climacteric symptoms were evaluated using an analog visual scale (AVS) and the SUMEVA index. For statistical analysis t student test was used as well as Chi squared. 105 women, 50 of Mexico City and 55 of Maxcanu, Yucatan were studied. When comparing the groups no difference was found in age (52.5 +/- 6.5 vs 53.7 +/- 6.2, for group I and II respectively), the body mass index was significantly smaller in group I (29.7 +/- 5.0 vs 34.0 +/- 6.0, p Mexico City women, which allows suppose that western culture influence can be the responsible.

  15. Emissions from biomass burning in the Yucatan

    Directory of Open Access Journals (Sweden)

    R. J. Yokelson

    2009-08-01

    Full Text Available In March 2006 two instrumented aircraft made the first detailed field measurements of biomass burning (BB emissions in the Northern Hemisphere tropics as part of the MILAGRO project. The aircraft were the National Center for Atmospheric Research C-130 and a University of Montana/US Forest Service Twin Otter. The initial emissions of up to 49 trace gas or particle species were measured from 20 deforestation and crop residue fires on the Yucatan peninsula. This included two trace gases useful as indicators of BB (HCN and acetonitrile and several rarely, or never before, measured species: OH, peroxyacetic acid, propanoic acid, hydrogen peroxide, methane sulfonic acid, and sulfuric acid. Crop residue fires emitted more organic acids and ammonia than deforestation fires, but the emissions from the main fire types were otherwise fairly similar. The Yucatan fires emitted unusually high amounts of SO2 and particle chloride, likely due to a strong marine influence on this peninsula. As smoke from one fire aged, the ratio ΔO3/ΔCO increased to ~15% in <~1 h similar to the fast net production of O3 in BB plumes observed earlier in Africa. The rapid change in O3 occurs at a finer spatial scale than is employed in global models and is also faster than predicted by micro-scale models. Fast increases in PAN, H2O2, and two organic acids were also observed. The amount of secondary organic acid is larger than the amount of known precursors. Rapid secondary formation of organic and inorganic aerosol was observed with the ratio ΔPM2.5/ΔCO more than doubling in ~1.4±0.7 h. The OH measurements revealed high initial levels (>1×107 molecules/cm3 that were likely caused in part by high initial HONO (~10% of NOy. Thus, more research is needed to understand critical post emission processes for the second-largest trace gas source on Earth. It is estimated that

  16. [Obesity, body morphology, and blood pressure in urban and rural population groups of Yucatan].

    Science.gov (United States)

    Arroyo, Pedro; Fernández, Victoria; Loría, Alvar; Pardío, Jeannette; Laviada, Hugo; Vargas-Ancona, Lizardo; Ward, Ryk

    2007-01-01

    To characterize body morphology and blood pressure of adults of the Mexican state of Yucatan. Rural-urban differences in weight, height, waist, and hip circumferences, and blood pressure were analyzed in 313 urban and 271 rural subjects. No rural-urban differences in prevalence of obesity and overweight were found. Hypertension was marginally higher in urban subjects. Rural abnormal waist circumference was higher in young men and young women. Comparison with two national surveys and a survey in the aboriginal population (rural mixtecos) showed similar prevalence of obesity as ENSA-2000 and higher than mixtecos and ENEC-1993. Abnormal waist circumference was intermediate between ENSANUT-2006 and mixtecos and hypertension was intermediate between ENEC and mixtecos. The Maya and mestizo population of Yucatan showed a high prevalence of obesity and abnormal waist circumference not accompanied by a comparable higher hypertension frequency. This finding requires further confirmation.

  17. Nematodes parasitic in fishes of cenotes (= sinkholes) of the Peninsula of Yucatan, Mexico. Part 1. Adults.

    Science.gov (United States)

    Moravec, F; Vivas-Rodríguez, C; Scholz, T; Vargas-Vázquez, J; Mendoza-Franco, E; González-Solís, D

    1995-01-01

    The present paper comprises a systematic survey of adult nematodes collected from fishes from cenotes (= sinkholes) of the Peninsula of Yucatan, southeastern Mexico, in 1993-1994. Examinations of a total of 533 fishes (17 species) originating from 39 cenotes from the Mexican states of Yucatan and Quintana Roo revealed the presence of the following nine nematode species: Rhabdochona (Rhabdochona) kidderi, Procamallanus (Spirocamallanus) rebecae, P. (S.) neocaballeroi, Philometroides caudata, Hysterothylacium cenotue. Pseudocapillaria yucatanensis, Paracapillaria rhamdiae, P. teixerafreitasi and Capillostrongyloides sp. (only females). Four species (R. kidderi, P. rebecae, P. neocaballeroi and Capillostrongyloides sp.) are briefly described and illustrated and some problems concerning their morphology, taxonomy, hosts and geographical distribution are discussed. Taxonomic changes include Procamallanus (Spirocamallanus) neocaballeroi (Caballero-Deloya. 1977) comb. n. and Procamallanus (Spirocamallanus) rebecae (Andrade-Salas, Pineda-López et García-Magaña, 1994) comb. n. The nematode fauna of fishes in cenotes of the Yucatan Peninsula shows its appurtenance to the Neotropical fauna with close affinities with that of fish nematodes from South America, but with a considerable degree of endemism.

  18. Association between overweight and obesity with school performance in secondary students in Merida, Mexico.

    Science.gov (United States)

    Salazar-Rendón, Juan Carlos; Méndez, Nina; Azcorra, Hugo

    2018-01-01

    Some studies have found a negative relationship between obesity and school performance in scholars. However, this topic has not been studied in depth in Mexico. The aim of this study was to analyze the association between overweight and obesity with school performance in secondary school students from Merida. Weight and height were measured, and body mass index was calculated in a sample of 566 secondary students in Merida. Nutritional status was classified in normal weight (-2- + 2 SD) according to the World Health Organization criteria. The scores in language, mathematics and sciences were used as indicators of school performance. Good performance was considered when the scores were ≥8 points, and poor performance when scores were <8 points. Logistic regression models were used to analyse the association between the variables. The 44% of the sample met the criteria for overweight and obesity. After adjusting for school grade, type of school, number of absences, and Mayan surnames, we found that girls classified as obese had a significant risk of a poor performance in mathematics (odds ratio [OR]: 3.07; 95% confidence interval [CI]: 1.39-6.80) and language (OR: 2.55; 95% CI: 1.14-5.71) compared with those with healthy weight. Our results suggest that obesity represents a risk of having a lower school performance in girls but not in boys. Copyright: © 2018 Permanyer.

  19. Deltamethrin resistance in Aedes aegypti results in treatment failure in Merida, Mexico.

    Science.gov (United States)

    Vazquez-Prokopec, Gonzalo M; Medina-Barreiro, Anuar; Che-Mendoza, Azael; Dzul-Manzanilla, Felipe; Correa-Morales, Fabian; Guillermo-May, Guillermo; Bibiano-Marín, Wilbert; Uc-Puc, Valentín; Geded-Moreno, Eduardo; Vadillo-Sánchez, José; Palacio-Vargas, Jorge; Ritchie, Scott A; Lenhart, Audrey; Manrique-Saide, Pablo

    2017-06-01

    The operational impact of deltamethrin resistance on the efficacy of indoor insecticide applications to control Aedes aegypti was evaluated in Merida, Mexico. A randomized controlled trial quantified the efficacy of indoor residual spraying (IRS) against adult Ae. aegypti in houses treated with either deltamethrin (to which local Ae. aegypti expressed a high degree of resistance) or bendiocarb (to which local Ae. aegypti were fully susceptible) as compared to untreated control houses. All adult Ae. aegypti infestation indices during 3 months post-spraying were significantly lower in houses treated with bendiocarb compared to untreated houses (odds ratio houses. On average, bendiocarb spraying reduced Ae. aegypti abundance by 60% during a 3-month period. Results demonstrate that vector control efficacy can be significantly compromised when the insecticide resistance status of Ae. aegypti populations is not taken into consideration.

  20. Ticks collected from humans, domestic animals, and wildlife in Yucatan, Mexico.

    Science.gov (United States)

    Rodríguez-Vivas, R I; Apanaskevich, D A; Ojeda-Chi, M M; Trinidad-Martínez, I; Reyes-Novelo, E; Esteve-Gassent, M D; Pérez de León, A A

    2016-01-15

    Domestic animals and wildlife play important roles as reservoirs of zoonotic pathogens that are transmitted to humans by ticks. Besides their role as vectors of several classes of microorganisms of veterinary and public health relevance, ticks also burden human and animal populations through their obligate blood-feeding habit. It is estimated that in Mexico there are around 100 tick species belonging to the Ixodidae and Argasidae families. Information is lacking on tick species that affect humans, domestic animals, and wildlife through their life cycle. This study was conducted to bridge that knowledge gap by inventorying tick species that infest humans, domestic animals and wildlife in the State of Yucatan, Mexico. Amblyomma ticks were observed as euryxenous vertebrate parasites because they were found parasitizing 17 animal species and human. Amblyomma mixtum was the most eryxenous species found in 11 different animal species and humans. Both A. mixtum and A. parvum were found parasitizing humans. Ixodes near affinis was the second most abundant species parasitizing six animal species (dogs, cats, horses, white-nosed coati, white-tail deer and black vulture) and was found widely across the State of Yucatan. Ixodid tick populations may increase in the State of Yucatan with time due to animal production intensification, an increasing wildlife population near rural communities because of natural habitat reduction and fragmentation. The diversity of ticks across host taxa documented here highlights the relevance of ecological information to understand tick-host dynamics. This knowledge is critical to inform public health and veterinary programs for the sustainable control of ticks and tick-borne diseases. Copyright © 2015. Published by Elsevier B.V.

  1. Tidal currents in the Yucatan Channel

    Energy Technology Data Exchange (ETDEWEB)

    Carrillo Gonzalez, Fatima [Centro Universitario de la Costa, Universidad de Guadalajara, Guadalajara, Jalisco (Mexico); Ochoa, Jose; Candela, Julio; Badan, Antonio; Sheinbaum; Gonzalez Navarro, Juan Ignacio [Departamento de Oceanografia Fisica, Centro de Investigacion Cientifica y de Educacion Superior de Ensenada, Ensenada, Baja California (Mexico)

    2007-07-15

    Currents data from a ten-month period at 197 measuring points covering all Yucatan Channel were processed by harmonic analysis to estimate tidal parameters for the O{sub 1}, K{sub 1}, M{sub 2} and S{sub 2} components. The highly detailed coverage confirms the known dominance for the O{sub 1} and K{sub 1} diurnal components, but also showed, for the first time, their intensification in the deep eastern margin of the channel where maximum amplitudes in main axis are 17 and 19 cm.s{sup -}1. The data also confirms weak semi-diurnal components, of which the most intense, M{sub 2} and S{sub 2}, have amplitudes only up to 2 cm.s{sup -}1. The tidal ellipses were elongated (i.e. with eccentricities close to one) in the NNW direction. The O{sub 1}, K{sub 1}, M{sub 2} and S{sub 2} contributions in transport variability through the channel have amplitudes of 11.7, 12.5, 1.2 and 1.0 Sv, all well determined above noise. [Spanish] Se presentan, a detalle sin precedente, las caracteristicas de las corrientes de marea O{sub 1}, K{sub 1}, M{sub 2} y S{sub 2} en el canal de Yucatan. Mapas de los parametros que definen las elipses, como son las amplitudes en los ejes principales, la orientacion, la fase y la razon-senal-ruido se obtienen, por el clasico analisis armonico en mediciones de 10 meses en duracion, en 197 puntos que cubren ampliamente un plano vertical del canal. En acuerdo con reportes anteriores, las senales diurnas O{sub 1} y K{sub 1} dominan, demostrandose aqui que sus amplitudes alcanzan, en la parte profunda y Este, 17 y 19 cm.s{sup -}1. El analisis tambien revela senales semidiurnas M{sub 2} y S{sub 2} muy debiles con amplitudes maximas de 2 y 1cm.s{sup -}1. Las elipses son muy alargadas (i.e. con excentricidad cercana a uno) y orientadas al nornoroeste. Los valores de la razon senal a ruido indican que los parametros de las dos constituyentes diurnas se encuentran bien determinados, mientras que las semidiurnas quedan muy contaminadas por el ruido. El rasgo mas

  2. Tuluweckelia cernua, a new genus and species of stygobiont amphipod crustacean (Hadziidae) from anchialine caves on the Yucatan Peninsula in Mexico

    NARCIS (Netherlands)

    Holsinger, John R.

    1990-01-01

    Tuluweckelia cernua, a new genus and species of stygobiont amphipod is described from six anchialine caves near the northeastern coast of the state of Quintana Roo on the Yucatan Peninsula in Mexico. The new genus is closely allied morphologically with Mayaweckelia Holsinger, which is also recorded

  3. Performance and genetic variation of big-leaf mahogany (Swietenia macrophylla King) in provenance and progeny trials in the Yucatan Peninsula of Mexico.

    Science.gov (United States)

    Kevyn E. Wightman; Sheila E. Ward; Jeremy P. Haggar; Bartolo Rodriguez Santiago; Jonathan P. Cornelius

    2008-01-01

    Stocks of the valuable big-leaf mahogany (Swietenia macrophylla King) are declining, and trials for growth and pest resistance are needed to select material for plantations. Seeds were collected from 67 open-pollinated trees from five provenances in the Yucatan Peninsula of Mexico and planted in three provenance/progeny trials in the state of Quintana Roo, Mexico, in...

  4. Frequency of Varroa destructor, Nosema spp and Acarapis woodi in commercial colonies of bees (Apis mellifera in Yucatan, Mexico

    Directory of Open Access Journals (Sweden)

    Martínez-Puc Jesús Froylán

    2015-10-01

    Full Text Available Today it has been observed that diseases affecting bees (Apis mellifera have caused significant economic losses in the European continent and in parts of the United States due to high mortality in honey bee colonies without a cause apparent, which is known as the syndrome of depopulation of hives. It is noteworthy that this mortality is not yet presented in Yucatan. In order to determine the frequency and levels of infestation Acarapis woodi and Varroa destructor, and the frequency and levels of infection Nosema spp. commercial colonies of bees (A. mellifera in Yucatan, was collected from June to December 2006, a total of 165 samples distributed in 13 towns of Yucatan. V. destructor frequency was 63.6%, with an average level of infestation of 2.85 ± 0.79 (mites / 100 bees. The frequency of Nosema spp. was 81.8%, with an average infection level = 1'234000 ± 118000 (spores / bee, the presence of A. woodi in the samples analyzed was detected. The existence of an association between V. destructor and Nosema spp was observed. (X2 = 6.53, df = 1, p = 0.01.

  5. Deltamethrin resistance in Aedes aegypti results in treatment failure in Merida, Mexico.

    Directory of Open Access Journals (Sweden)

    Gonzalo M Vazquez-Prokopec

    2017-06-01

    Full Text Available The operational impact of deltamethrin resistance on the efficacy of indoor insecticide applications to control Aedes aegypti was evaluated in Merida, Mexico. A randomized controlled trial quantified the efficacy of indoor residual spraying (IRS against adult Ae. aegypti in houses treated with either deltamethrin (to which local Ae. aegypti expressed a high degree of resistance or bendiocarb (to which local Ae. aegypti were fully susceptible as compared to untreated control houses. All adult Ae. aegypti infestation indices during 3 months post-spraying were significantly lower in houses treated with bendiocarb compared to untreated houses (odds ratio <0.75; incidence rate ratio < 0.65 whereas no statistically significant difference was detected between the untreated and the deltamethrin-treated houses. On average, bendiocarb spraying reduced Ae. aegypti abundance by 60% during a 3-month period. Results demonstrate that vector control efficacy can be significantly compromised when the insecticide resistance status of Ae. aegypti populations is not taken into consideration.

  6. [Control of Aedes aegypti breeding sites with the program Recicla por tu bienestar in Merida, Mexico].

    Science.gov (United States)

    Barrera-Pérez, Mario A; Pavía-Ruz, Norma; Mendoza-Mezquita, Jorge Eduardo; Torres-Arcila, Nerio; Hernández-Hernández, Ramón; Castro-Gamboa, Francisco; Geded-Moreno, Eduardo; Cohuo-Rodríguez, Azael; Medina-Barreiro, Anuar; Koyoc-Cardeña, Edgar; Gómez-Dantés, Héctor; Kroeger, Axel; Vázquez-Prokopec, Gonzalo; Manrique-Saide, Pablo

    2015-01-01

    To determine the importance of Ae. aegypti breeding-sites in Merida;to evaluate the impact of Recicla por tu bienestar (RxB, a recycling program) on the reduction of breeding sites and the perception of participants. The relative importance for pupae production of the different types of breeding-sites was determined. Pre-and post-RxB entomological surveys were performed in participant neighborhoods to evaluate the impact on total containers and positive breeding-sites. A survey on the perception of participating people about dengue prevention and control and RxB was applied. Buckets/pots and "small diverse items" were the most important breeding-sites. RxB had a significant impact in the reduction of total containers (IRR = 0.74), positive containers (IRR = 0.33) and the risk of a house being positive for Ae. aegypti (OR = 0.41). All the interviewed participants referred RxB as needed and most consider it useful. RxB should be considered as a good practice for the dengue vector control.

  7. An innovative ecohealth intervention for Chagas disease vector control in Yucatan, Mexico.

    Science.gov (United States)

    Waleckx, Etienne; Camara-Mejia, Javier; Ramirez-Sierra, Maria Jesus; Cruz-Chan, Vladimir; Rosado-Vallado, Miguel; Vazquez-Narvaez, Santos; Najera-Vazquez, Rosario; Gourbière, Sébastien; Dumonteil, Eric

    2015-02-01

    Non-domiciliated (intrusive) triatomine vectors remain a challenge for the sustainability of Chagas disease vector control as these triatomines are able to transiently (re-)infest houses. One of the best-characterized examples is Triatoma dimidiata from the Yucatan peninsula, Mexico, where adult insects seasonally infest houses between March and July. We focused our study on three rural villages in the state of Yucatan, Mexico, in which we performed a situation analysis as a first step before the implementation of an ecohealth (ecosystem approach to health) vector control intervention. The identification of the key determinants affecting the transient invasion of human dwellings by T. dimidiata was performed by exploring associations between bug presence and qualitative and quantitative variables describing the ecological, biological and social context of the communities. We then used a participatory action research approach for implementation and evaluation of a control strategy based on window insect screens to reduce house infestation by T. dimidiata. This ecohealth approach may represent a valuable alternative to vertically-organized insecticide spraying. Further evaluation may confirm that it is sustainable and provides effective control (in the sense of limiting infestation of human dwellings and vector/human contacts) of intrusive triatomines in the region. © The author 2015. The World Health Organization has granted Oxford University Press permission for the reproduction of this article.

  8. CONTRIBUTION TO THE KNOWLEDGE OF THE ARACHNIDS IN THE YUCATAN PENINSULA, MEXICO (EXCLUDING ARANAE AND ACARI

    Directory of Open Access Journals (Sweden)

    Hugo Delfin Gonzalez

    2017-08-01

    Full Text Available The Chelicerata are the second group of arthropods with the highest diversity after insects and they can inhabit almost all types of environments. The most current classification recognizes 11 orders and estimates in the number of species vary from 52,000 to 100,000. We have made an extensive literature review on the diversity of arachnids in the Yucatan Peninsula (YP (excluding spiders and ticks. In Mexico there are 834 known species which represent 6% of the worldwide diversity. In the YP 63 records were found (58 species and 5 genera of arachnids, which represent 6.8% of the Mexican species. According to our research, 28 of the 58 species (48% in the YP were also record in other parts of Mexico, the continent and the world. Undoubtedly, the state of Yucatan is the best represented of the YP. In order to have a better understanding of the diversity of arachnid species is important to promote biological compendiums and sampling programs, which will improve the representation of this group and probably increasing the number of local species.

  9. Indication of a species in an extinction vortex: The ocellated turkey on the Yucatan peninsula, Mexico

    Science.gov (United States)

    Kampichler, Christian; Calmé, Sophie; Weissenberger, Holger; Arriaga-Weiss, Stefan Louis

    2010-11-01

    The ocellated turkey Meleagris ocellata (OT) is a large, unmistakable endemic bird of the Yucatan peninsula. The species has suffered a considerable loss of distributional area as well as local abundance between 1980 and 2000 and is classified as endangered according to Mexican norms. We applied Classification Trees and Random Forests in order to determine the factors that most closely explain the observed patterns of distribution and abundance loss, and to develop hypotheses that may guide measures for the protection of the OT. Among the most important predictors of change were variables corresponding to aspects of forest cover and variables on human population and small settlements. OT abundance in 1980, however, was by far the most important predictor for OT abundance change. This is an indication that the OT dynamics are governed by internal rather than by external factors. Medium and low abundances in 1980 inevitably led to a further decrease during the following years, which gives rise to the conclusion that the OT might find itself in an extinction vortex. We suggest the following hypothetical scenario for OT decline: migrant people from other Mexican states colonise forested regions in Yucatan; they establish small settlements; bushmeat hunting is important for their survival; the naïve OT is easy prey; hunting—together with beginning deforestation—reaches a certain level, and local OT abundance falls below a critical threshold; OT continues declining regardless of current social and environmental changes except where there is total protection of both the species and its habitat.

  10. Shaded Relief with Height as Color and Landsat, Yucatan Peninsula, Mexico

    Science.gov (United States)

    2003-01-01

    The top picture is a shaded relief image of the northwest corner of Mexico's Yucatan Peninsula generated from Shuttle Radar Topography Mission (SRTM) data, and shows a subtle, but unmistakable, indication of the Chicxulub impact crater. Most scientists now agree that this impact was the cause of the Cretatious-Tertiary Extinction, the event 65 million years ago that marked the sudden extinction of the dinosaurs as well as the majority of life on Earth. The pattern of the crater's rim is marked by a trough, the darker green semicircular line near the center of the picture. This trough is only about 3 to 5 meters (10 - 15 feet) deep and is about 5 km (3 miles) wide; so subtle that if you walked across it you probably would not notice it. It is the surface expression of the buried crater's outer boundary. Scientists believe the impact, which was centered just off the coast in the Caribbean, altered the subsurface rocks such that the overlying limestone sediments, which formed later and erode very easily, would preferentially erode along the crater rim. This formed the trough as well as numerous sinkholes (called cenotes) which are visible as small circular depressions.The bottom picture is the same area viewed by the Landsat satellite, and was made by displaying the Thematic Mapper's Band 7 (mid-infrared), Band 4 (near-infrared) and Band 2 (green) as red, green and blue. These colors were chosen to maximize the contrast between different vegetation and land cover types, with native vegetation and cultivated land showing as green, yellow and magenta, and urban areas as white. The circular white area near the center of the image is Merida, a city of about 720,000 population. Notice that in the SRTM image, which shows only topography, the city is not visible, while in the Landsat image, which does not show elevations, the trough is not visible.Two visualization methods were combined to produce the SRTM image: shading and color coding of topographic height. The shade

  11. Chemical constraints of groundwater management in the Yucatan peninsula, Mexico

    Science.gov (United States)

    Back, W.; Lesser, J. M.

    1981-05-01

    Two critical objectives of water management in the Yucatan are: (1) to develop regional groundwater supplies for an expanding population and tourism based on the Mayan archeological sites and excellent beaches; and (2) to control groundwater pollution in a chemically sensitive system made vulnerable by geologic conditions. The Yucatan peninsula is a coastal plain underlain by permeable limestone and has an annual rainfall of more than 1000 mm. Such a setting should provide abundant supplies of water; however, factors of climate and hydrogeology have combined to form a hydrologic system with chemical boundaries that decrease the amount of available fresh water. Management of water resources has long had a major influence on the cultural and economic development of the Yucatan. The Mayan culture of the northern Yucatan developed by extensive use of groundwater. The religion was water-oriented and the Mayan priests prayed to Chac, the water god, for assistance in water management primarily to decrease the severity of droughts. The Spaniards arrived in 1517 and augmented the supplies by digging wells, which remained the common practice for more than 300 years. Many wells now have been abandoned because of serious problems of pollution resulting from the use of a sewage disposal well adjacent to each supply well. The modern phase of water management began in 1959 when the Secretaría de Recursos Hidráulicos (S.R.H.) was charged with the responsibility for both scientific investigations and development programmes for water-supply and sewage-disposal systems for cities, villages and islands.

  12. Water management by early people in the Yucatan, Mexico

    Science.gov (United States)

    Back, W.

    1995-06-01

    The Yucatan Peninsula is a coastal plain underlain by permeable limestone and receives abundant rainfall. Such hydrogeologic conditions should provide major supplies of water; however, factors of climate and hydrogeology have combined to form a hydrologic system with chemical boundaries that limits the amount of fresh water available. Management of water resources has long had a major influence on the cultural and economic development of the Yucatan. The Mayan culture of the northern Yucatan developed on extensive use of groundwater. The religion was water oriented and the Mayan priests prayed to Chac, the water god, for assistance in water management, primarily to decrease the severity of droughts. The Spaniards arrived in 1517 and augmented the supply by digging wells, which remained the common practice for more than 300 years. Many wells now have been abandoned because of serious problems of pollution. A historical perspective of a paper such as this provides insight into the attitudes concerning water of early people and perhaps provides insight into current attitudes concerning water. Hydrogeologists possess the expertise to generate relevant information required by water managers to arrive at management programs to achieve sustainable development.

  13. Variability and Dynamics of the Yucatan Upwelling: High-Resolution Simulations

    Science.gov (United States)

    Jouanno, J.; Pallàs-Sanz, E.; Sheinbaum, J.

    2018-02-01

    The Yucatan shelf in the southern Gulf of Mexico is under the influence of an upwelling that uplifts cool and nutrient rich waters over the continental shelf. The analysis of a set of high-resolution (Δx = Δy ≈ 2.8 km) simulations of the Gulf of Mexico shows two dominant modes of variability of the Yucatan upwelling system: (1) a low-frequency mode related to variations in position and intensity of the Loop Current along the shelf, with upwelling intensified when the Loop Current is strong and approaches to the Yucatan shelf break and (2) a high-frequency mode with peak frequency in the 6-10 days band related to wind-forced coastal waves that force vertical velocities along the eastern Yucatan shelf break. To first order, the strength and position of the Loop Current are found to control the intensity of the upwelling, but we show that high-frequency winds also contribute (˜17%) to a net input of cool waters (<22.5°C) on the Yucatan shelf. Finally, although more observational studies are needed to corroborate the topographic character of the Yucatan upwelling system, this study reveals the key role played by a notch along the Yucatan shelf break: a sensitivity simulation without the notch shows a 55% reduction of the upwelling.

  14. The taxonomic status of the Yucatan brown brocket, Mazama pandora (Mammalia: Cervidae)

    Science.gov (United States)

    Medellin, R.A.; Gardner, A.L.; Aranda, J.M.

    1998-01-01

    The Yucatan brown brocket deer, described as Mazama pandora, is now treated as a subspecies of either the common brown brocket, Mazama gouazoubira, or of the red brocket, M. americana. Analysis of brocket deer from Mexico and Central and South America, reveals that the Yucatan brown brocket is sympatric with the red brocket in Mexico and, while similar to M. gouazoubira, warrents recognition as a separate species.

  15. Rickettsia lusitaniae associated with Ornithodoros yumatensis (Acari: Argasidae) from two caves in Yucatan, Mexico.

    Science.gov (United States)

    Sánchez-Montes, Sokani; Guzmán-Cornejo, Carmen; Martínez-Nájera, Yecenia; Becker, Ingeborg; Venzal, José M; Labruna, Marcelo B

    2016-10-01

    The genus Rickettsia includes obligate intracellular bacteria transmitted by several hematophagous arthropods such as ticks, fleas and sucking lice. In particular hard ticks (Ixodidae) have been cited as the main vectors of pathogenic rickettsiae in Mexico. However, there have been only two records of a single Rickettsia species associated with Mexican soft ticks (Argasidae). In this study, we searched for rickettsial DNA in argasid ticks (13 adults and eight nymphs of Ornithodoros yumatensis) from two bat caves in the state of Yucatan, Mexico. Additionally one larva collected in a cave from Chiapas, Mexico, and associated with Desmodus rotundus was used to corroborate the tick taxonomic determination. Of these, nine ticks (43%) yielded expected PCR products for the rickettsial gltA gene. These PCR-positive ticks were tested with additional PCR protocols targeting the rickettsial genes gltA, ompA and ompB. DNA partial sequences from these genes showed 99-100% identities with Rickettsia lusitaniae, an agent isolated from O. erraticus in Portugal, and closely related to R. felis and R. hoogstraalii. Based on the results from this study, the inventory of rickettsiae distributed in Mexico increases from six to seven species. Copyright © 2016 Elsevier GmbH. All rights reserved.

  16. Exploring the genetic signature of body size in Yucatan miniature pig.

    Science.gov (United States)

    Kim, Hyeongmin; Song, Ki Duk; Kim, Hyeon Jeong; Park, WonCheoul; Kim, Jaemin; Lee, Taeheon; Shin, Dong-Hyun; Kwak, Woori; Kwon, Young-jun; Sung, Samsun; Moon, Sunjin; Lee, Kyung-Tai; Kim, Namshin; Hong, Joon Ki; Eo, Kyung Yeon; Seo, Kang Seok; Kim, Girak; Park, Sungmoo; Yun, Cheol-Heui; Kim, Hyunil; Choi, Kimyung; Kim, Jiho; Lee, Woon Kyu; Kim, Duk-Kyung; Oh, Jae-Don; Kim, Eui-Soo; Cho, Seoae; Lee, Hak-Kyo; Kim, Tae-Hun; Kim, Heebal

    2015-01-01

    Since being domesticated about 10,000-12,000 years ago, domestic pigs (Sus scrofa domesticus) have been selected for traits of economic importance, in particular large body size. However, Yucatan miniature pigs have been selected for small body size to withstand high temperature environment and for laboratory use. This renders the Yucatan miniature pig a valuable model for understanding the evolution of body size. We investigate the genetic signature for selection of body size in the Yucatan miniature pig. Phylogenetic distance of Yucatan miniature pig was compared to other large swine breeds (Yorkshire, Landrace, Duroc and wild boar). By estimating the XP-EHH statistic using re-sequencing data derived from 70 pigs, we were able to unravel the signatures of selection of body size. We found that both selections at the level of organism, and at the cellular level have occurred. Selection at the higher levels include feed intake, regulation of body weight and increase in mass while selection at the molecular level includes cell cycle and cell proliferation. Positively selected genes probed by XP-EHH may provide insight into the docile character and innate immunity as well as body size of Yucatan miniature pig.

  17. Exploring the genetic signature of body size in Yucatan miniature pig.

    Directory of Open Access Journals (Sweden)

    Hyeongmin Kim

    Full Text Available Since being domesticated about 10,000-12,000 years ago, domestic pigs (Sus scrofa domesticus have been selected for traits of economic importance, in particular large body size. However, Yucatan miniature pigs have been selected for small body size to withstand high temperature environment and for laboratory use. This renders the Yucatan miniature pig a valuable model for understanding the evolution of body size. We investigate the genetic signature for selection of body size in the Yucatan miniature pig. Phylogenetic distance of Yucatan miniature pig was compared to other large swine breeds (Yorkshire, Landrace, Duroc and wild boar. By estimating the XP-EHH statistic using re-sequencing data derived from 70 pigs, we were able to unravel the signatures of selection of body size. We found that both selections at the level of organism, and at the cellular level have occurred. Selection at the higher levels include feed intake, regulation of body weight and increase in mass while selection at the molecular level includes cell cycle and cell proliferation. Positively selected genes probed by XP-EHH may provide insight into the docile character and innate immunity as well as body size of Yucatan miniature pig.

  18. Lower limb direct skeletal attachment. A Yucatan micropig pilot study.

    Science.gov (United States)

    Saunders, Marnie M; Brecht, J Stephen; Verstraete, Mary C; Kay, David B; Njus, Glen O

    2012-12-01

    Regardless of the type of prosthetic lower limb, successful ambulation requires proper prosthetic attachment. To help alleviate many of the problems associated with prosthetic attachment, direct skeletal attachment (DSA) has been proposed as an alternative to conventional sockets. The purpose of the current study was to evaluate the feasibility of lower limb DSA in a micropig model and to develop a systematic approach to the development and analysis of DSA systems. The DSA device consisted of two stages. The load-carrying stage embedded in the bone canal was designed using bone remodeling theory in conjunction with finite element analysis to approximate implant-induced remodeling and stabilization out to 36 months postimplantation. The skin-interfacing stage was designed to maintain an immutable infection barrier where the prosthesis exited the body. Following successful design, fabrication, and benchtop evaluation, the device was surgically implanted in a Yucatan micropig. The animal trial was successful out to 10 weeks and revealed potential flaws in the surgical protocol related to thermal necrosis. However, no signs of infection were present at the time of implant retrieval. While results of this pilot study support the feasibility of a DSA approach to prosthetic limb attachment, additional animal trials are necessary to prove long-term viability.

  19. Microbial deterioration of Mayan stone buildings at Uxmal, Yucatan, Mexico

    International Nuclear Information System (INIS)

    Ortega-Morales, O.; Guezennec, J.; Hernandez D, G.; Jozsa, P.; Sand, W.; Crassous, P.

    1998-01-01

    The microbial communities associated to Uxmal Mayan monuments (Yucatan, Mexico) and their role in stone deterioration were preliminary characterized by chemical, biochemical, microbiological, microscopical and surface analysis methods under two climatic seasons (1997). The organic matter and organic carbon and nitrogen were in the range of those reported for other stone buildings, indicating that oligo trophic conditions prevail at Uxmal. Quantitative differences in microbial biomass was higher at indoor section were the organic matter content was the highest and micro-environmental conditions (availability of water and protection to direct sunlight) are more suitable for microbial growth. The microbiological analysis underestimated the microbial biomass, as revealed by biochemical approaches. Nitrate and nitrite-oxidizing, metilotrophic and heterotrophic bacteria and fungi were detected in most surfaces. The heterotrophic bacteria were the most abundant microbial group (microbiological data). However, the chlorophyll profiles and Scanning Electron Microscopy showed that the microalgae are the most abundant colonizers in Uxmal stone buildings. EDAX analysis showed that the most surfaces were covered by an organic layer (cells and exo polymers). Gypsum was found in few samples. The large photo trophic biomass seems to play a role in stone bio deterioration by supporting growth of heterotrophic microorganisms (bacteria and fungi) which are known to produce organic acids leading to calcite dissolution and cations chelation. Further studies are being carried out in order to determine the role of exo polysaccharides which are thought to play a role in chemical degradation of limestone substrates in Uxmal. (Author)

  20. Chicxulub Impact Crater and Yucatan Carbonate Platform - PEMEX Oil Exploratory Wells Revisited

    Science.gov (United States)

    Pérez-Drago, G.; Gutierrez-Cirlos, A. G.; Pérez-Cruz, L.; Urrutia-Fucugauchi, J.

    2008-12-01

    Geophysical oil exploration surveys carried out by PEMEX in the 1940's revealed occurrence of an anomalous pattern of semi-circular concentric gravity anomalies. The Bouguer gravity anomalies covered an extensive area over the flat carbonate platform in the northwestern Yucatan Peninsula; strong density contrasts were suggestive of a buried igneous complex or basement uplift beneath the carbonates, which was referred as the Chicxulub structure. The exploration program carried out afterwards included a drilling program, starting with Chicxulub-1 well in 1952 and comprising eight deep boreholes through the 1970s. An aeromagnetic survey in late 1970's showed high amplitude anomalies in the gravity anomaly central sector. Thus, research showing Chicxulub as a large complex impact crater formed at the K/T boundary was built on the PEMEX decades-long exploration program. Despite frequent reference to PEMEX information and samples, original data and cores have not been openly available for detailed evaluation and integration with results from recent investigations. Core samples largely remain to be analyzed and interpreted in the context of recent marine, aerial and terrestrial geophysical surveys and the drilling/coring projects of UNAM and ICDP. In this presentation we report on the stratigraphy and paleontological data for PEMEX wells: Chicxulub- 1 (1582m), Sacapuc-1 (1530m), Yucatan-6 (1631m), Ticul-1 (3575m) Yucatan-4 (2398m), Yucatan-2 (3474m), Yucatan-5A (3003m) and Yucatan-1 (3221m). These wells remain the deepest drilled in Chicxulub, providing samples of impact lithologies, carbonate sequences and basement, which give information on post- and pre-impact stratigraphy and crystalline basement. We concentrate on stratigraphic columns, lateral correlations and integration with UNAM and ICDP borehole data. Current plans for deep drilling in Chicxulub crater target the peak ring and central sector, with offshore and onshore boreholes proposed to the IODP and ICDP

  1. Regional-scale airborne electromagnetic surveying of the Yucatan karst aquifer (Mexico): geological and hydrogeological interpretation

    DEFF Research Database (Denmark)

    Gondwe, Bibi Ruth Neuman; Ottowitz, David; Supper, Robert

    2012-01-01

    Geometry and connectivity of high-permeability zones determine groundwater flow in karst aquifers. Efficient management of karst aquifers requires regional mapping of preferential flow paths. Remote-sensing technology provides tools to efficiently map the subsurface at such scales. Multi......-spectral remote sensing imagery, shuttle radar topography data and frequency-domain airborne electromagnetic (AEM) survey data were used to map karst-aquifer structure on the Yucatan Peninsula, Mexico. Anomalous AEM responses correlated with topographic features and anomalous spectral reflectance of the terrain...... with remote-sensing data analysis provide a potentially powerful multi-scale methodology for structural mapping in karst aquifers on the Yucatan Peninsula and beyond....

  2. Shaded Relief with Height as Color, Yucatan Peninsula, Mexico

    Science.gov (United States)

    2003-01-01

    This shaded relief image of Mexico's Yucatan Peninsula show a subtle, but unmistakable, indication of the Chicxulub impact crater. Most scientists now agree that this impact was the cause of the Cretatious-Tertiary Extinction, the event 65 million years ago that marked the sudden extinction of the dinosaurs as well as the majority of life then on Earth.Most of the peninsula is visible here, along with the island of Cozumel off the east coast. The Yucatan is a plateau composed mostly of limestone and is an area of very low relief with elevations varying by less than a few hundred meters (about 500 feet.) In this computer-enhanced image the topography has been greatly exaggerated to highlight a semicircular trough, the darker green arcing line at the upper left corner of the peninsula. This trough is only about 3 to 5 meters (10 to 15 feet) deep and is about 5 km. wide (3 miles), so subtle that if you walked across it you probably would not notice it, and is a surface expression of the crater's outer boundary. Scientists believe the impact, which was centered just off the coast in the Caribbean, altered the subsurface rocks such that the overlying limestone sediments, which formed later and erode very easily, would preferentially erode on the vicinity of the crater rim. This formed the trough as well as numerous sinkholes (called cenotes) which are visible as small circular depressions.Two visualization methods were combined to produce the image: shading and color coding of topographic height. The shade image was derived by computing topographic slope in the northwest-southeast direction, so that northwestern slopes appear bright and southeastern slopes appear dark. Color coding is directly related to topographic height, with green at the lower elevations, rising through yellow and tan, to white at the highest elevations.For a smaller, annotated version of this image, please select Figure 1, below: [figure removed for brevity, see original site] (Large image: 1.5 m

  3. Groundwater-flow modeling in the Yucatan karstic aquifer, Mexico

    Science.gov (United States)

    González-Herrera, Roger; Sánchez-y-Pinto, Ismael; Gamboa-Vargas, José

    2002-09-01

    The current conceptual model of the unconfined karstic aquifer in the Yucatan Peninsula, Mexico, is that a fresh-water lens floats above denser saline water that penetrates more than 40 km inland. The transmissivity of the aquifer is very high so the hydraulic gradient is very low, ranging from 7-10 mm/km through most of the northern part of the peninsula. The computer modeling program AQUIFER was used to investigate the regional groundwater flow in the aquifer. The karstified zone was modeled using the assumption that it acts hydraulically similar to a granular, porous medium. As part of the calibration, the following hypotheses were tested: (1) karstic features play an important role in the groundwater-flow system; (2) a ring or belt of sinkholes in the area is a manifestation of a zone of high transmissivity that facilitates the channeling of groundwater toward the Gulf of Mexico; and (3) the geologic features in the southern part of Yucatan influence the groundwater-flow system. The model shows that the Sierrita de Ticul fault, in the southwestern part of the study area, acts as a flow barrier and head values decline toward the northeast. The modeling also shows that the regional flow-system dynamics have not been altered despite the large number of pumping wells because the volume of water pumped is small compared with the volume of recharge, and the well-developed karst system of the region has a very high hydraulic conductivity. Résumé. Le modèle conceptuel classique de l'aquifère karstique libre de la péninsule du Yucatan (Mexique) consiste en une lentille d'eau douce flottant sur une eau salée plus dense qui pénètre à plus de 40 km à l'intérieur des terres. La transmissivité de l'aquifère est très élevée, en sorte que le gradient hydraulique est très faible, compris entre 7 et 10 mm/km dans la plus grande partie du nord de la péninsule. Le modèle AQUIFER a été utilisé pour explorer les écoulements souterrains régionaux dans cet

  4. Prevalence of the metabolic syndrome, insulin resistance index, leptin and thyroid hormone levels in the general population of Merida (Venezuela).

    Science.gov (United States)

    Uzcátegui, Euderruh; Valery, Lenin; Uzcátegui, Lilia; Gómez Pérez, Roald; Marquina, David; Baptista, Trino

    2015-06-01

    The metabolic syndrome (MetSyn) is a significant risk factor for cardiovascular events, but scarce information exists about its frequency in Venezuela. In this cross-sectional study, we quantified the prevalence of the MetSyn in a probabilistic, stratified sample of 274 subjects aged > or =18 years from the Libertador district in Merida, Venezuela. Secondary outcomes were the measurement of thyroid hormones (free T4 and TSH), leptin levels, and insulin resistance index (HOMA2-IR). The frequency of MetSyn (percentage +/- 95% confidence interval) according to several diagnostic criteria was as follows: National Cholesterol Education Panel (NCEP, original): 27.4% (22.1-32.7); modified NCEP: 31.8% (26.3-37.3); International Diabetes Federation: 40.9% (35.1-46.7); Latin American Diabetes Association: 27% (21.7-32.3), and Venezuelan criteria: 31.8% (26.3-37.3). The MetSyn was more frequent in males than in females with most diagnostic criteria. The estimated prevalence of type 2 diabetes mellitus was 2.9% either according to the patients' self reports or to fasting glucose level found to be above 126 mg/dL. Abnormal HOMA2-IR index, free T4 and TSH (above the 95th percentile) were detected in 4.5%, 4.4% and 5.1% of the sample, respectively. Free T4 and TSH levels below the 5th percentile were detected in 4.4% and 4.7% of subjects respectively. These values are presented for comparisons with forthcoming studies in specific clinical populations. While studies are being conducted about the different definitions of the MetSyn in Venezuela, we recommend analyzing and publishing local research data with all the available criteria so as to allow comparisons with the results already reported in the literature.

  5. A preliminary study on the preparation of wood-plastic composites from urban wastes generated in Merida, Mexico with potential applications as building materials.

    Science.gov (United States)

    Cruz-Estrada, Ricardo H; Martínez-Tapia, Gustavo E; Canché-Escamilla, Gonzalo; González-Chí, Pedro I; Martín-Barrera, Cesar; Duarte-Aranda, Santiago; Guillén-Mallette, Javier; Cupul-Manzano, Carlos V; Martínez-Domínguez, Osvaldo; García-Gómez, Carmen

    2010-09-01

    A preliminary study on the use of wood and plastic wastes generated in Merida, Mexico to assess their potential for the development of building materials is reported. Composites based on recycled, high-density polyethylene (R-HDPE) loaded with wood particles were prepared. The R-HDPE was collected from Merida's Separation Plant, where it was sorted from other residues, either organic or inorganic. Composites based on virgin, high-density polyethylene (V-HDPE) were also prepared to assess the effect of the R-HDPE on the composite's mechanical properties. The wood came from the trims of different varieties of the city's trees that are periodically pruned as part of the cleaning and urbanising programmes implemented by the City Council. A batch of this material was selected at random to incorporate into both the R-HDPE and V-HDPE. Different wood particle sizes were experimented with to obtain extruded composites with contents of 50% and 60% by weight of wood that were characterized under tension and impact. Flat wood-plastic extrudates with reasonable good appearance were also produced at the laboratory level as a first step to find an adequate route to scale-up the process to a pilot level to evaluate the feasibility of producing alternative building materials.

  6. Modeling carbon stocks in a secondary tropical dry forest in the Yucatan Peninsula, Mexico

    Science.gov (United States)

    Zhaohua Dai; Richard A. Birdsey; Kristofer D. Johnson; Juan Manuel Dupuy; Jose Luis Hernandez-Stefanoni; Karen. Richardson

    2014-01-01

    The carbon balance of secondary dry tropical forests of Mexico’s Yucatan Peninsula is sensitive to human and natural disturbances and climate change. The spatially explicit process model Forest-DeNitrification-DeComposition (DNDC) was used to estimate forest carbon dynamics in this region, including the effects of disturbance on carbon stocks. Model evaluation using...

  7. SUBACTUTE HEMATOLOGICAL RESPONSES OF THE YUCATAN SAILFIN MOLLY (POECILIA VELIFERA) EXPOSED TO CADMIUM CHLORIDE

    Science.gov (United States)

    This study focuses on the subacute hematological responses of the Yucatan sailfin molly, Poecilia velifera, exposed to cadmium chloride. Previous studies in other teleosts and mammals have suggested that exposure to cadmium chloride results in a leucocytic response. Fish were exp...

  8. Mechanisms of the 40-70 Day Variability in the Yucatan Channel Volume Transport

    Science.gov (United States)

    van Westen, René M.; Dijkstra, Henk A.; Klees, Roland; Riva, Riccardo E. M.; Slobbe, D. Cornelis; van der Boog, Carine G.; Katsman, Caroline A.; Candy, Adam S.; Pietrzak, Julie D.; Zijlema, Marcel; James, Rebecca K.; Bouma, Tjeerd J.

    2018-02-01

    The Yucatan Channel connects the Caribbean Sea with the Gulf of Mexico and is the main outflow region of the Caribbean Sea. Moorings in the Yucatan Channel show high-frequent variability in kinetic energy (50-100 days) and transport (20-40 days), but the physical mechanisms controlling this variability are poorly understood. In this study, we show that the short-term variability in the Yucatan Channel transport has an upstream origin and arises from processes in the North Brazil Current. To establish this connection, we use data from altimetry and model output from several high resolution global models. A significant 40-70 day variability is found in the sea surface height in the North Brazil Current retroflection region with a propagation toward the Lesser Antilles. The frequency of variability is generated by intrinsic processes associated with the shedding of eddies, rather than by atmospheric forcing. This sea surface height variability is able to pass the Lesser Antilles, it propagates westward with the background ocean flow in the Caribbean Sea and finally affects the variability in the Yucatan Channel volume transport.

  9. Reverse polarity magnetized melt rocks from the Chicxulub impact structure, Yucatan Peninsula, Mexico

    Science.gov (United States)

    Urrutia-Fucugauchi, Jaime; Marin, Luis E.; Sharpton, Virgil L.; Quezada, Juan Manuel

    1993-03-01

    Further paleomagnetic data for core samples of melt rock recovered in the Petroleos Mexicanos (PEMEX) exploratory wells within the Chicxulub structure, northern Yucatan peninsula, Mexico are reported. A previous report by Sharpton showed that the rocks studied contain high iridium levels and shocked breccia clasts, and an Ar-40/Ar-39 age of 65.2 plus or minus 0.4 Ma. The geomagnetic polarity determined for two samples is reverse (R) and was correlated with chron 29R that includes the K/T boundary. Our present analysis is based on two samples from each of three clasts of the melt rock from PEMEX well Y6-N17 (1295 to 1299 m b.s.l.). This study concentrates on the vectorial nature and stability of the remanence (NRM), the magnetic mineralogy and remanence carriers (i.e., the reliability and origin of the record), and on the implications (correlation with expected paleolatitude and polarity). The relative orientation of the drill core samples with respect to the horizontal is known. Samples were stable under alternating field (AF) and thermal treatments, and after removal of a small component they exhibited single-vectorial behavior. The characteristic remanence inclinations show small dispersion and a mean value (-43 deg) in close agreement with the expected inclination and paleolatitude (derived from the North American apparent polar wander path). Isothermal remenence (IRM) acquisition experiments, Lowrie-Fuller tests, coercivity and unblocking temperature spectra of NRM and saturation IRM, susceptibility and Q-coefficient analyses, and the single-component nature indicate a dominant mineralogy of iron-rich titanomagnetites with single or pseduo-single domain states. The stable characteristic magnetization may be interpreted as a result of shock heating of the rock at the time of formation of the inpact structure and its polarity, age, and paleolatitude are consistent with a time about the K/T boundary.

  10. U.S.- Mexican Security Cooperation: The Merida Initiative and Beyond

    Science.gov (United States)

    2010-07-29

    police forces engaged in counterdrug efforts. Escalating drug trafficking -related violence in Mexico and the increasing control that Mexican drug ... trafficking organizations (DTOs) have over the illicit drug market in the United States have focused congressional attention on the efficacy of U.S

  11. Climate Change Scenarios in the Yucatan Peninsula to the year 2020

    Science.gov (United States)

    Orellana, R.; Espadas, C.; Conde, C.; Gay, C.

    2010-03-01

    A topic that has not been sufficiently analyzed is that the global warming is already affecting, and that it will have worst consequences in those regions with transitional climates, which have more sensibility to changes. This is the case of the Yucatan Peninsula which is semi-arid in their northern portion, and toward the south is subhumid, with a tendency to be more rainy toward the south. To have an estimation of what could happen in the future, the Intergovernmental Panel of Climatic Change (IPCC) has promoted the use of General Circulation Models (GCM), as well as the construction of possible emission scenarios that integrate different global and regional socioeconomic and demographic conditions, which project then a possible increase of emissions of greenhouse gases. These conditions are recognized as the decisive forces that will determine the variations of temperature and of precipitation. These projections are useful for the analysis of climatic change, and in particular for the assessments of the possible impacts and of the initiatives of adaptation and of mitigation that should be implemented in every country or region. In Mexico, most of those evaluations of climate change have been carried out generally at country level. For that reason, it is necessary to direct the research at regional level. In this work, we evaluated the potential climatic changes on the Yucatan Peninsula, considering the different changes of temperature and precipitation as a consequence for different emission scenarios and for the horizon 2020. To project the environmental responses of the region, we used as a base scenario the available temperature and precipitation information of the period 1961-1990, registered in 85 meteorological stations of the peninsula. With these data, we generated climate change scenarios using the outputs of four General Circulation Models: HADLEY, ECHAM, GFDL and CGCM, and the emission scenarios A1FI, A2, B1 and B2. The outputs of these models were

  12. Space Radar Image of the Yucatan Impact Crater Site

    Science.gov (United States)

    1999-01-01

    This is a radar image of the southwest portion of the buried Chicxulub impact crater in the Yucatan Peninsula, Mexico. The radar image was acquired on orbit 81 of space shuttle Endeavour on April 14, 1994 by the Spaceborne Imaging Radar C/X-Band Synthetic Aperture Radar (SIR-C/X-SAR). The image is centered at 20 degrees north latitude and 90 degrees west longitude. Scientists believe the crater was formed by an asteroid or comet which slammed into the Earth more than 65 million years ago. It is this impact crater that has been linked to a major biological catastrophe where more than 50 percent of the Earth's species, including the dinosaurs, became extinct. The 180-to 300-kilometer-diameter (110- to 180-mile)crater is buried by 300 to 1,000 meters (1,000 to 3,000 feet) of limestone. The exact size of the crater is currently being debated by scientists. This is a total power radar image with L-band in red, C-band in green, and the difference between C-band L-band in blue. The 10-kilometer-wide (6-mile) band of yellow and pink with blue patches along the top left (northwestern side) of the image is a mangrove swamp. The blue patches are islands of tropical forests created by freshwater springs that emerge through fractures in the limestone bedrock and are most abundant in the vicinity of the buried crater rim. The fracture patterns and wetland hydrology in this region are controlled by the structure of the buried crater. Scientists are using the SIR-C/X-SAR imagery to study wetland ecology and help determine the exact size of the impact crater. Spaceborne Imaging Radar-C and X-band Synthetic Aperture Radar (SIR-C/X-SAR) is part of NASA's Mission to Planet Earth. The radars illuminate Earth with microwaves allowing detailed observations at any time, regardless of weather or sunlight conditions. SIR-C/X-SAR uses three microwave wavelengths: L-band (24 cm), C-band (6 cm) and X-band (3 cm). The multi-frequency data will be used by the international scientific community

  13. Merida Initiative and Effectiveness: An Analysis of Supply-Side Policy

    Science.gov (United States)

    2013-06-01

    producers and shipping routes for illicit drugs, and the United States is the largest consumer in the world. According to the edict of supply-side counter...opiate-based drugs (commonly referred to as heroin), both of which are mainly produced in Latin America. It is worth noting that the use of cannabis ...4.97 (0.8–0.9%) Opiates 1.31–1.36 (0.4–0.5%) 1.29–1.38 (0.4–0.5%) 3.44–4.05 (0.6–0.7%) 3.29–3.8 (0.6–0.7%) Cannabis 31.26 (10.5%) 29.95

  14. EVIL, WITCHCRAFT AND LOSS OF GOODWILL RELATED TO SUICIDE AMONG THE MAYA YUCATAN

    Directory of Open Access Journals (Sweden)

    Mundo Alberto Ramírez-Camacho

    2017-01-01

    Full Text Available This article raises observe the importance that exists for people of two communities in the eastern of Yucatan, Cuncunul and Chemax, the concept of evil as well as one of its causes and consequences, witchcraft and loss of will in the Yucatecan individuals, this by information disclosed in the notes field diary. The analysis of this sketch of an uncertainty that originated in the ethnographic work, which focused on knowing what people meant when they talked of evil associated with suicide; I consider stopping to observe and reflect on this concept will allow to better understand social relations and reality go around in daily life in the communities of eastern Yucatan about suicide by hanging.

  15. First molecular evidence of Toxoplasma gondii in opossums (Didelphis virginiana) from Yucatan, Mexico

    OpenAIRE

    Torres-Castro, M.; Noh-Pech, H.; Puerto-Hern?ndez, R.; Reyes-Hern?ndez, B.; Panti-May, A.; Hern?ndez-Betancourt, S.; Yeh-Gorocica, A.; Gonz?lez-Herrera, L.; Zavala-Castro, J.; Puerto, F.I.

    2016-01-01

    Toxoplasma gondii is an obligate intracellular parasite recognized as a causal agent of toxoplasmosis; zoonotic disease endemic in many countries worldwide, including Mexico. Different species of animals participate in the wild cycle infection, including opossums of the species Didelphis virginiana. Thirteen D. virginiana were captured in Yucatan, Mexico. Detection of T. gondii was achieved by Polymerase Chain Reaction, which determined an infection of 76.9% (10/13) in brains. Positive amplic...

  16. Sedimentology and Community Structure of Reefs of the Yucatan Peninsula, Mexico

    OpenAIRE

    Novak, Matthew J.

    1992-01-01

    Holocene carbonate sediments from Mexican reefs in the Caribbean and Gulf of Mexico display variations in constituent composition, texture and mineralogy which are related to their locations on the reefs. Samples were collected at barrier reef environments at Akumal and Chemuyil, on the northeast coast of the Yucatan Peninsula; at the oceanic atoll of Chinchorro, off the southeast coast of the peninsula; and at the shelf atoll of Alacranes, in the Gulf of Mexico. Samples were collected throug...

  17. Leishmanicidal evaluation of extracts from native plants of the Yucatan peninsula.

    Science.gov (United States)

    Peraza-Sánchez, S R; Cen-Pacheco, F; Noh-Chimal, A; May-Pat, F; Simá-Polanco, P; Dumonteil, E; García-Miss, M R; Mut-Martín, M

    2007-06-01

    Methanol extracts were prepared from different parts of 18 plants collected in the Yucatan peninsula and evaluated in an in vitro bioassay for leishmanicidal activity against Leishmania mexicana promastigotes. The ten most potent plant extracts (IC(50)Byrsonima bucidaefolia bark, Byrsonima crassifolia bark, Clusia flava leaves, Cupania dentata bark, Diphysa carthagenensis leaves, Dorstenia contrajerva whole plant, Milleria quinqueflora roots, Tridax procumbens whole plant, and Vitex gaumeri bark.

  18. Targeted disruption of LDLR causes hypercholesterolemia and atherosclerosis in Yucatan miniature pigs.

    Directory of Open Access Journals (Sweden)

    Bryan T Davis

    Full Text Available Recent progress in engineering the genomes of large animals has spurred increased interest in developing better animal models for diseases where current options are inadequate. Here, we report the creation of Yucatan miniature pigs with targeted disruptions of the low-density lipoprotein receptor (LDLR gene in an effort to provide an improved large animal model of familial hypercholesterolemia and atherosclerosis. Yucatan miniature pigs are well established as translational research models because of similarities to humans in physiology, anatomy, genetics, and size. Using recombinant adeno-associated virus-mediated gene targeting and somatic cell nuclear transfer, male and female LDLR+/- pigs were generated. Subsequent breeding of heterozygotes produced LDLR-/- pigs. When fed a standard swine diet (low fat, no cholesterol, LDLR+/- pigs exhibited a moderate, but consistent increase in total and LDL cholesterol, while LDLR-/- pigs had considerably elevated levels. This severe hypercholesterolemia in homozygote animals resulted in atherosclerotic lesions in the coronary arteries and abdominal aorta that resemble human atherosclerosis. These phenotypes were more severe and developed over a shorter time when fed a diet containing natural sources of fat and cholesterol. LDLR-targeted Yucatan miniature pigs offer several advantages over existing large animal models including size, consistency, availability, and versatility. This new model of cardiovascular disease could be an important resource for developing and testing novel detection and treatment strategies for coronary and aortic atherosclerosis and its complications.

  19. Targeted disruption of LDLR causes hypercholesterolemia and atherosclerosis in Yucatan miniature pigs.

    Science.gov (United States)

    Davis, Bryan T; Wang, Xiao-Jun; Rohret, Judy A; Struzynski, Jason T; Merricks, Elizabeth P; Bellinger, Dwight A; Rohret, Frank A; Nichols, Timothy C; Rogers, Christopher S

    2014-01-01

    Recent progress in engineering the genomes of large animals has spurred increased interest in developing better animal models for diseases where current options are inadequate. Here, we report the creation of Yucatan miniature pigs with targeted disruptions of the low-density lipoprotein receptor (LDLR) gene in an effort to provide an improved large animal model of familial hypercholesterolemia and atherosclerosis. Yucatan miniature pigs are well established as translational research models because of similarities to humans in physiology, anatomy, genetics, and size. Using recombinant adeno-associated virus-mediated gene targeting and somatic cell nuclear transfer, male and female LDLR+/- pigs were generated. Subsequent breeding of heterozygotes produced LDLR-/- pigs. When fed a standard swine diet (low fat, no cholesterol), LDLR+/- pigs exhibited a moderate, but consistent increase in total and LDL cholesterol, while LDLR-/- pigs had considerably elevated levels. This severe hypercholesterolemia in homozygote animals resulted in atherosclerotic lesions in the coronary arteries and abdominal aorta that resemble human atherosclerosis. These phenotypes were more severe and developed over a shorter time when fed a diet containing natural sources of fat and cholesterol. LDLR-targeted Yucatan miniature pigs offer several advantages over existing large animal models including size, consistency, availability, and versatility. This new model of cardiovascular disease could be an important resource for developing and testing novel detection and treatment strategies for coronary and aortic atherosclerosis and its complications.

  20. Changes in stature, weight, and nutritional status with tourism-based economic development in the Yucatan.

    Science.gov (United States)

    Leatherman, Thomas L; Goodman, Alan H; Stillman, Tobias

    2010-07-01

    Over the past 40 years, tourism-based economic development has transformed social and economic conditions in the Yucatan Peninsula, Mexico. We address how these changes have influenced anthropometric indicators of growth and nutritional status in Yalcoba, a Mayan farming community involved in the circular migration of labor in the tourist economy. Data are presented on stature and weight for children measured in 1938 in the Yucatan Peninsula and from 1987 to 1998 in the Mayan community of Yalcoba. In addition, stature, weight and BMI are presented for adults in Yalcoba based on clinic records. Childhood stature varied little between 1938 and 1987. Between 1987 and 1998 average male child statures increased by 2.6cm and female child statures increased by 2.7cm. Yet, 65% of children were short for their ages. Between 1987 and 1998, average child weight increased by 1.8kg. Child BMIs were similar to US reference values and 13% were considered to be above average for weight. Forty percent of adult males and 64% of females were overweight or obese. The anthropometric data from Yalcoba suggest a pattern of stunted children growing into overweight adults. This pattern is found elsewhere in the Yucatan and in much of the developing world where populations have experienced a nutrition transition toward western diets and reduced physical activity levels. 2010 Elsevier B.V. All rights reserved.

  1. Restoring the environment, revitalizing the culture: cenote conservation in Yucatan, Mexico

    Directory of Open Access Journals (Sweden)

    Yolanda Lopez-Maldonado

    2017-12-01

    Full Text Available Cenotes are sinkholes through which groundwater may be accessed from the Yucatan Peninsula Aquifer. Historically and culturally, cenotes are also important cultural and spiritual natural sites for the Maya, but they have been contaminated and degraded. We ask the following: What are the present-day meanings, understanding, and values of cenotes for the Maya? Is it possible to adopt a cultural approach for conservation of cenotes in Yucatan? Participant observation, interviews with stakeholders, and underwater exploration in cenotes were used to obtain data. Results indicate that cenotes often retain some spiritual meaning for people but not as important cultural, spiritual, or sacred sites. Little consensus was found regarding the significance of cenotes and how best to protect them. Informants noted changes in water quality, and identified the threats to cenotes including tourism, poor solid waste management, contamination, and deficiency of interest in preservation. Lack of accurate knowledge was a problem: informants did not seem to understand that cenotes are interconnected through the groundwater system. The Yucatan case illustrates how loss of cultural values can be linked to environmental quality and resource degradation. Conversely, it can be argued that cultural revitalization in indigenous communities has the potential to bring back community-based conservation.

  2. Chicxulub Impact Crater and Yucatan Carbonate Platform - Stratigraphy and Petrography of PEMEX Borehole Cores

    Science.gov (United States)

    Gutierrez-Cirlos, A. G.; Perez-Drago, G.; Perez-Cruz, L.; Urrutia-Fucugauchi, J.

    2008-12-01

    Chicxulub impact crater is the best preserved of the three large multi-ring structures documented in the terrestrial record. Chicxulub, formed 65 Ma ago, is associated with the Cretaceous/Tertiary (K/T) boundary layer and the impact related to the organism extinctions and events marking the boundary. The crater is buried under Tertiary sediments in the Yucatan carbonate platform in the southern Gulf of Mexico. The structure was initially recognized from gravity and magnetic anomalies in the PEMEX exploration surveys of the northwestern Yucatan peninsula. The exploration program included eight deep boreholes completed from 1952 through the 1970s. The investigations showing Chicxulub as a large complex impact crater formed at the K/T boundary have relayed on the PEMEX decades-long exploration program. However, despite frequent use of PEMEX information and core samples, significant parts of the database and cores remain to be evaluated, analyzed and incorporated with results from recent efforts. Access to PEMEX Core Repository has permitted to study the cores and collect new samples from some of the boreholes. We analyzed cores from Yucatan-6, Chicxulub-1, Sacapuc-1, Ticul-1, Yucatan-1 and Yucatan-4 boreholes to make new detailed stratigraphic correlations and petrographic characterization, using information from PEMEX database and the recent studies. In C-1 cores, breccias show 4-8 cm clasts of fine grained altered melt dispersed in a medium to coarse grained matrix composed of pyroxene and feldspar with little macroscopic alteration. Clasts contain 0.2 to 0.1 cm fragments of silicate material (basement) that show variable degrees of digestion. Melt samples from C-1 N10 comes from interval 1,393-1,394 m, and show a fine-to-medium grained coherent microcrystalline groundmass. Melt and breccias in Y-6 extend from about 1,100 m to more than 1,400 m. Sequence is well sorted, with an apparent gradation in both the lithic and melt clasts. In this presentation we report on

  3. Design and validation of a scale to identify stereotypes against indigenous people

    OpenAIRE

    Rebelín Echeverría Echeverría; Mirta Margarita Flores Galaz

    2013-01-01

    The aim of this study was to design and validate a scale to identify prejudices against indigenous people as a socially stigmatised and culturally relevant group in Mexican samples, and establishing gender differences in undergraduate students. A sample of 563 undergraduate students was drawn from Merida, the capital city, and inner towns in the state of Yucatan, Mexico. From the sample, 272 were women and 292 were men with an average age of 23.06 years. To measure beliefs scale was developed...

  4. THE EMERGING WORLD SYSTEM AND COLONIAL YUCATAN:THE ARCHAEOLOGY OF CORE-PERIPHERY INTEGRATION, 1780-1847

    Directory of Open Access Journals (Sweden)

    Rani T. Alexander

    2015-08-01

    Full Text Available The conquest and colonization of Mesoamerica by Spain during the period AD 1519-1821 forms part of a macroregional interaction network known as the modern or capitalist world system. Regions incorporated within the world-system usually undergo economic change such that production and labor are increasingly commoditized, dramatically altering the productive strategies of households and communities. As Price (1986 observes, world systems theory is difficult to apply to prehistoric or precapitalist macroregional systems because the world systems analogy lacks referents to broader processes of state expansion, political-economic structure, and the corresponding archaeological record. This paper uses archaeological and historical data from the Parroquia de Yaxcaba, Yucatan, to explore the variable impact of political and economic change on the organization of production and labor of rural communities. Archaeological site structure and spatial organization are analyzed to assess the implications of world-system expansion for the archaeological record in a region where the market transitionultimately fails. Settlement patterns and site structure in Yaxcaba Parish suggest variation in production organization among communities that differs from historical reconstructions. Comparison of independent lines of evidence indicates that variation inthe processes of core-periphery integration are archaeologically recognizable.

  5. Contaminants in the coastal karst aquifer system along the Caribbean coast of the Yucatan Peninsula, Mexico

    International Nuclear Information System (INIS)

    Metcalfe, Chris D.; Beddows, Patricia A.; Bouchot, Gerardo Gold; Metcalfe, Tracy L.; Li Hongxia; Van Lavieren, Hanneke

    2011-01-01

    Intensive land development as a result of the rapidly growing tourism industry in the 'Riviera Maya' region of the Yucatan Peninsula, Mexico may result in contamination of groundwater resources that eventually discharge into Caribbean coastal ecosystems. We deployed two types of passive sampling devices into groundwater flowing through cave systems below two communities to evaluate concentrations of contaminants and to indicate the possible sources. Pharmaceuticals and personal care products accumulated in the samplers could only have originated from domestic sewage. PAHs indicated contamination by runoff from highways and other impermeable surfaces and chlorophenoxy herbicides accumulated in samplers deployed near a golf course indicated that pesticide applications to turf are a source of contamination. Prevention and mitigation measures are needed to ensure that expanding development does not impact the marine environment and human health, thus damaging the tourism-based economy of the region. - Research highlights: → Intensive land development as a result of the rapidly growing tourism industry in the 'Riviera Maya' region of the Yucatan Peninsula, Mexico is contaminating groundwater resources that discharge into Caribbean coastal ecosystems. → Passive sampling devices deployed in groundwater flowing through cave systems below two communities in the Riviera Maya accumulated: pharmaceuticals and personal care products originating from domestic sewage. → PAHs originating from runoff from highways and other impermeable surfaces; chlorophenoxy herbicides originating from pesticide applications to lawns and turf. → Prevention and mitigation measures are needed to ensure that expanding development does not impact the marine environment and human health in the region. - Contaminants accumulated in passive samplers deployed in flooded cave systems in the Yucatan Peninsula in Mexico indicate contamination by domestic sewage, runoff and applications of pesticides

  6. CONTRIBUTION TO THE KNOWLEDGE OF THE ARACHNIDS IN THE YUCATAN PENINSULA, MEXICO (EXCLUDING ARANAE AND ACARI)

    OpenAIRE

    Hugo Delfin Gonzalez; Virginia Meléndez-Ramírez; Pablo C. Manrique-Saide; Abdiel Martin-Park; Carlos Arisqueta-Chablé

    2017-01-01

    The Chelicerata are the second group of arthropods with the highest diversity after insects and they can inhabit almost all types of environments. The most current classification recognizes 11 orders and estimates in the number of species vary from 52,000 to 100,000. We have made an extensive literature review on the diversity of arachnids in the Yucatan Peninsula (YP) (excluding spiders and ticks). In Mexico there are 834 known species which represent 6% of the worldwide diversity. In the YP...

  7. Frecuencia de anticuerpos contra el virus C de la hepatitis en pacientes con cirrosis hepática en Yucatán, México Frequency of antibodies against the hepatitis C virus in patients with hepatic cirrhosis in Yucatan, Mexico

    Directory of Open Access Journals (Sweden)

    Renán A Góngora-Biachi

    2003-10-01

    Full Text Available OBJETIVO: En este estudio reportamos la prevalencia de anticuerpos contra el virus C de la hepatitis (Ac-VCH en un grupo de pacientes con cirrosis hepática (CH. MATERIAL Y MÉTODOS: Se hizo un estudio prospectivo, transversal y descriptivo, de marzo de 1998 a mayo de 1999. Se estudiaron a 153 pacientes (117 (76% hombres y 36 (24% mujeres con diagnóstico de CH, que eran atendidos en el Hospital General Agustín O' Horan y en el Centro de Investigaciones Regionales Doctor Hideyo Noguchi, en la ciudad de Mérida, Yucatán, México. Se aplicó un cuestionario con datos clínico-epidemiológicos y se determinó la presencia de Ac-VCH (ELISA de 2ª generación y RIBA-2 para confirmar el diagnóstico a cada paciente. Se determinó también el antígeno de superficie de la hepatitis B (AgsHB y anticuerpos contra el antígeno central de la hepatitis B (Anti-HBc mediante el método de ELISA. La presencia de Ac-VCH fue relacionada con las variables epidemiológicas de los sujetos. La prevalencia de anti-HCV y la frecuencia de características se compararon entre los pacientes positivos y negativos con las pruebas de c² y exacta de Fisher. RESULTADOS: El 32% de los pacientes con CH (35/117 (30% hombres y 14/36 (39% mujeres fueron positivos para los Ac-VCH. El alcoholismo estuvo presente en todos los hombres serorreactivos y en ninguna de las mujeres positivas (pOBJECTIVE: To report the prevalence of antibodies against the hepatitis C virus (anti-HCV in a group of patients with hepatic cirrhosis (HC. MATERIAL AND METHODS: A prospective transversal and descriptive study was carried out from March 1998 to May 1999. Study subjects were 153 patients; 117 (76% male and 36 (24% female, diagnosed with HC. They were attended at the General Hospital Agustín O' Horan and at Regional Research Center Doctor Hideyo Noguchi, in Merida, Yucatan, Mexico. A clinical-epidemiologic questionnaire completed by interview was used for data collection. Anti-HCV were detected

  8. Petroleum systems at the triple point between the Merida Andes, the eastern cordillera of Colombia and the Guayana shield: The petroleum geology of the Colombian-Venezuelan Border

    Energy Technology Data Exchange (ETDEWEB)

    Chigne, N.; Loureiro, D.; Rojas, L. [and others

    1996-08-01

    The sinistral Bramon-Bucaramanga shear zone, in conjunction with the southeastern vergent Falla Borde Llanero and the northwestern vergent frontal thrust of the Merida Andes, defines a complex area where tectonic transport shows crustal scale shift. Palinspastic restorations have been used as a base for the identification and reconstruction of the evolving petroleum systems, showing that several of the discontinuities within this collage served as barriers for major oil accumulations. The main oil generating unit of the region is a 200-m-thick sequence of Cenomanian-Turonian rocks representing a variety of facies, from siliciclastic mudstones to finely laminated limestones. Sequence stratigraphy at well-log scale combined with seismic profiles has helped to identify and map the most important reservoir-seal couples within Late Cretaceous and late Eocene-Early Miocene megasequences. One- and two-dimensional modelling of kerogen maturation suggest a major phase of oil expulsion during Early Miocene. Loading of the source rock below Upper Miocene to Holocene thrust and/or coeval foredeep sediments has developed a petroleum system that is active today. Oil migrated toward the local highs from active kitchens located to the west-southwest.

  9. Validation of an indirect ELISA for the diagnosis of Babesia bovis in cattle in Yucatan, Mexico

    International Nuclear Information System (INIS)

    Dominguez, A.J.L.; Rodriguez, V.R.I.; Oura, C.; Cob, G.L.A.

    1998-01-01

    The ELISA kit provided by the FAO/IAEA for the diagnosis of Babesia bovis was validated. In order to determine the appropriate ELISA cut-off point that would serve as the threshold between positive and negative samples, 119 serum samples from a Mexican Babesia-free zone were analyzed. The optimal cut-off point chosen was at 12% of the reactivity of the high positive control serum sample (PP) which resulted in a specificity of 97%. One hundred and ninety-six cattle from Wisconsin, USA, were introduced into Yucatan, Mexico, of which 181 were vaccinated with an attenuated live Babesia bovis vaccine; 15 animals remained as unvaccinated controls. Before and after vaccination all animals were bled and tested by enzyme linked immunosorbent assay (ELISA) and indirect fluorescence antibody test (IFAT). Both tests showed a high degree of correlation in their results. To evaluate an immune response to vaccination the optimal cut-off point chosen was 12% PP resulting in a sensitivity 99% and a specificity 95%. We concluded that the ELISA test has proved to be useful in Yucatan, Mexico for serological surveys and monitoring the efficiency o vaccination programmes. (author)

  10. Pigging the unpiggable: a total integrated maintenance approach of the Progreso Process Pipelines in Yucatan, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Sanchez Graciano, Luis [PEMEX Refinacion, Mexico, MX (Mexico); Gonzalez, Oscar L. [NDT Systems and Services, Stutensee (Germany)

    2009-07-01

    Pemex Refinacion and NDT Systems and Services, executed a Total Integrated Maintenance Program of the Process Pipeline System in the Yucatan Peninsula in Mexico, in order to modernize, enhance and bring the pipeline system up to the best industry standards and ensure the integrity, reliability and safe operation of the system. This approach consisted in using multi-diameter ultrasonic inspection technology to determine the current status of the pipelines, repair every 'integrity diminishing' feature present on the system and establish a Certified Maintenance Program to ensure the future reliability and safety of the pipelines. Due to the complex nature of the pipeline construction, dated from 1984, several special modifications, integrations and solutions were necessary to improve the in line inspection survey as for all traditionally unpiggable systems. The Progreso Pipeline System consists in 3 major pipelines which transport diesel, jet fuel and gasoline respectively. The outside diameter of two pipelines varies along its length between 12 inches - 14 inches - 16 inches, making the inspection survey more difficult and particularly demanding an Inspection Tool solution. It is located on the coast of the Yucatan Peninsula, at the Mexican Caribbean, and its main purpose is to transport the product from the docked tanker ships to the Pemex Storage and Distribution Terminal. (author)

  11. Low prevalence of HTLV-II in Mayan Indians in the Yucatan Peninsula, Mexico.

    Science.gov (United States)

    Gongora-Biachi, R A; Lal, R B; Rudolph, D L; Castro-Sansores, C; Gonzalez-Martinez, P; Pavia-Ruz, N

    1997-01-01

    Infection with HTLV-II is endemic in Amerindians, with prevalence ranging from 0.89% - 33%. To determine the prevalence of HTLV-II among indigenous Mayans in the Yucatan Peninsula of Mexico, 440 indigenous Mayans were recruited, all native to and residents of one of six Mayan communities in the Yucatan Peninsula, (Xohuayan n=144, Yaxachen n=101, Kanxoc n=84, Xocen n=40, Nabalan n=46 and X'calot n=25) between May, 1992 and June, 1993. All of the above are pre-Hispanic settlements located in tropical forest with no immigrations for over 50 years. Of the 440 indigenous Mayans, only one woman from the X'calot tribe (0.23%) was shown to be infected with HTLV-II. A high percentage of indeterminate results was found (22/439, 5%), three of which were accounted for by the husband and two children of the positive female case. PCR analysis followed by specific restriction digestion demonstrated the virus to be of the HTLV-IIb subtype, similar to that described in the Guaymi Indians from Panama. The presence of HTLV-II in the Mayan ethnos, and in other Amerindian populations supports the idea that HTLV-II is an ancestral virus in America and that it has been sustained in "closed" communities.

  12. Orthobunyaviruses, a Common Cause of Infection of Livestock in the Yucatan Peninsula of Mexico

    Science.gov (United States)

    Blitvich, Bradley J.; Saiyasombat, Rungrat; Travassos da Rosa, Amelia; Tesh, Robert B.; Calisher, Charles H.; Garcia-Rejon, Julian E.; Farfán-Ale, José A.; Loroño, Rubén E.; Bates, Arturo; Loroño-Pino, Maria A.

    2012-01-01

    To determine the seroprevalence of selected orthobunyaviruses in livestock in the Yucatan Peninsula of Mexico, a serologic investigation was performed using serum samples from 256 domestic animals (182 horses, 31 sheep, 1 dog, 37 chickens, and 5 turkeys). All serum samples were examined by plaque reduction neutralization test using Cache Valley virus (CVV), Cholul virus (CHLV), South River virus (SOURV), Kairi virus, Maguari virus, and Wyeomyia virus. Of the 182 horses, 60 (33.0%) were seropositive for CHLV, 48 (26.4%) were seropositive for CVV, 1 (0.5%) was seropositive for SOURV, 60 (33.0%) had antibodies to an undetermined orthobunyavirus, and 13 (7.1%) were negative for orthobunyavirus-specific antibody. Of the 31 sheep, 6 (19.3%) were seropositive for CHLV, 3 (9.7%) were seropositive for CVV, 4 (12.9%) were seropositive for SOURV, 16 (51.6%) had antibodies to an undetermined orthobunyavirus, and 2 (6.5%) were negative for orthobunyavirus-specific antibody. The single dog was seropositive for SOURV. Four (11%) chickens had antibodies to an undetermined orthobunyavirus, and 1 (20%) turkey was seropositive for CHLV. These data indicate that orthobunyaviruses commonly infect livestock in the Yucatan Peninsula. PMID:23045250

  13. Wildlife uses and hunting patterns in rural communities of the Yucatan Peninsula, Mexico

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    Santos-Fita Dídac

    2012-10-01

    Full Text Available Abstract Background Subsistence hunting is a traditional practice providing food and many other goods for households in the Yucatan Peninsula, southeast Mexico. Economic, demographic, and cultural change in this region drive wildlife habitat loss and local extinctions. Improving our understanding about current practices of wildlife use may support better management strategies for conserving game species and their habitat. We aimed to evaluate if wildlife use remained relevant for the subsistence of rural residents of the Yucatan Peninsula, as well as if local hunting practices were related to environmental, geographical, and cultural factors. Methods Fieldwork was done between March 2010 and March 2011. Information was obtained through conversations, interviews, and participant observation. Record forms allowed recording animals hunted, biomass extracted, distance intervals to hunting sites, habitat types and seasonality of wildlife harvests. Data were analyzed using one-way Analysis of Variance, and Generalized Linear Models. Results Forty-six terrestrial vertebrate species were used for obtaining food, medicine, tools, adornments, pets, ritual objects, and for sale and mitigating damage. We recorded 968 animals taken in 664 successful hunting events. The Great Curassow, Ocellated Turkey, paca, white-tailed deer, and collared peccary were the top harvested species, providing 80.7% of biomass (10,190 kg. The numbers of animals hunted and biomass extracted declined as hunting distances increased from villages. Average per capita consumption was 4.65 ± 2.7 kg/person/year. Hunting frequencies were similar in forested and agricultural areas. Discussion Wildlife use, hunting patterns, and technologies observed in our study sites were similar to those recorded in previous studies for rural Mayan and mestizo communities in the Yucatan Peninsula and other Neotropical sites. The most heavily hunted species were those providing more products and by

  14. U.S. Coast Guard Addendum to the United States National Search and Rescue Supplement (NSS) to the International Aeronautical and Maritime Search and Rescue Manual (IAMSAR)

    Science.gov (United States)

    2009-09-01

    SECTORS HEADQUARTERS (CITY, STATE) Gulf and Caribbean Coasts 1 Tampico, Tamaulipas Matamoros, Tamaulipas 3 Veracruz , Veracruz Tuxpan, Veracruz ...Coatacoalcos, Veracruz 5 Cuidad del Carmen, Campeche Frontera, Tabasco Champoton, Campeche Lerma, Campeche 7 Yukalpeten, Yucatan Progreso, Yucatan...from NOCD Asheville. For sale by the Supt. of the Docs. North Pacific Ocean (1985) NAVAIR 50-1C-539. S/N 0850 LP 014 2000. AD-A165 871. Shipping

  15. Yucatan Current transport derived from Satellite Altimetry observations from 1992-10-14 to 2016-11-30 (NCEI Accession 0159420)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This archive package contains estimates of the transport of the Yucatan Current generated by NOAA's Atlantic Oceanographic and Meteorological Laboratory (AOML). The...

  16. MaritimeMaya2011: The Costa Escondida Project: Exploring the Hidden World of the Maritime Maya on the Yucatan Peninsula between 20110509 and 20110531

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The northeast tip of the Yucatan Peninsula is a largely unexplored coastline where ancient Maya traders traveled in massive dugout canoes filled with goods from...

  17. Infection levels of intestinal helminths in two commensal rodent species from rural households in Yucatan, Mexico.

    Science.gov (United States)

    Panti-May, J A; Hernández-Betancourt, S F; Rodríguez-Vivas, R I; Robles, M R

    2015-01-01

    The aim of the present study was to calculate the prevalence and intensity of intestinal helminths in the house mouse (Mus musculus) and the black rat (Rattus rattus) trapped in rural households of Yucatan, Mexico. Sampling was conducted during the rainy season from October to December 2011 and the dry season from January to March 2012. A total of 154 M. musculus and 46 R. rattus were examined, with 84.2% of M. musculus being infected with helminths compared with a significantly lower prevalence of 52.2% in R. rattus (Pcommensal rodents present in households appears to constitute a low potential health risk to local inhabitants; however, it would be advisable to conduct further studies to better understand the public health risk posed by these rodent intestinal helminths.

  18. Prevalence of pediculosis capitis in children from a rural school in Yucatan, Mexico

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    Pablo Manrique-Saide

    2011-12-01

    Full Text Available We conducted an analytical cross-sectional survey to estimate the prevalence of and factors associated with active head lice infestation. In total 140 children, aged 6 to 16-years, from a public school in rural Yucatan, Mexico, were examined by wet-combing. A structured questionnaire was used to collect information on individuals and the conditions in the surrounding environment. Head lice infestation was found in 19 out of the 140 children tested (13.6% and this was associated with both lower income (OR 9.9, 95% CI 2.15-45.79, p = 0.003 and a higher frequency of hair washing (OR 8, 95% CI 1.58-50, p = 0.012. Intersectoral control programs that take into account the socioeconomic differences of children should be implemented.

  19. First molecular evidence of Toxoplasma gondii in opossums (Didelphis virginiana from Yucatan, Mexico

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    M. Torres-Castro

    2016-03-01

    Full Text Available Toxoplasma gondii is an obligate intracellular parasite recognized as a causal agent of toxoplasmosis; zoonotic disease endemic in many countries worldwide, including Mexico. Different species of animals participate in the wild cycle infection, including opossums of the species Didelphis virginiana. Thirteen D. virginiana were captured in Yucatan, Mexico. Detection of T. gondii was achieved by Polymerase Chain Reaction, which determined an infection of 76.9% (10/13 in brains. Positive amplicons were sequenced for analysis, this produced results similar to T. gondii with identity and coverage values of 98% and 96-100%, respectively. This study presents the first molecular evidence of the circulation of T. gondii in D. virginiana from Mexico.

  20. First molecular evidence of Toxoplasma gondii in opossums (Didelphis virginiana) from Yucatan, Mexico.

    Science.gov (United States)

    Torres-Castro, M; Noh-Pech, H; Puerto-Hernández, R; Reyes-Hernández, B; Panti-May, A; Hernández-Betancourt, S; Yeh-Gorocica, A; González-Herrera, L; Zavala-Castro, J; Puerto, F I

    2016-01-01

    Toxoplasma gondii is an obligate intracellular parasite recognized as a causal agent of toxoplasmosis; zoonotic disease endemic in many countries worldwide, including Mexico. Different species of animals participate in the wild cycle infection, including opossums of the species Didelphis virginiana. Thirteen D. virginiana were captured in Yucatan, Mexico. Detection of T. gondii was achieved by Polymerase Chain Reaction, which determined an infection of 76.9% (10/13) in brains. Positive amplicons were sequenced for analysis, this produced results similar to T. gondii with identity and coverage values of 98% and 96-100%, respectively. This study presents the first molecular evidence of the circulation of T. gondii in D. virginiana from Mexico.

  1. INFECTION BY Rickettsia felis IN OPOSSUMS (Didelphis sp.) FROM YUCATAN, MEXICO.

    Science.gov (United States)

    Peniche-Lara, Gaspar; Ruiz-Piña, Hugo A; Reyes-Novelo, Enrique; Dzul-Rosado, Karla; Zavala-Castro, Jorge

    2016-01-01

    Rickettsia felis is an emergent pathogen and the causative agent of a typhus-like rickettsiosis in the Americas. Its transmission cycle involves fleas as biological vectors (mainly Ctenocephalides felis) and multiple domestic and synanthropic mammal hosts. Nonetheless, the role of mammals in the cycle of R. felis is not well understood and many efforts are ongoing in different countries of America to clarify it. The present study describes for the first time in Mexico the infection of two species of opossum (Didelphis virginiana and D. marsupialis) by R. felis. A diagnosis was carried out from blood samples by molecular methods through the gltA and 17 kDa genes and sequence determination. Eighty-seven opossum samples were analyzed and 28 were found to be infected (32.1%) from five out of the six studied localities of Yucatan. These findings enable recognition of the potential epidemiological implications for public health of the presence of infected synanthropic Didelphis in households.

  2. Contaminants in the coastal karst aquifer system along the Caribbean coast of the Yucatan Peninsula, Mexico.

    Science.gov (United States)

    Metcalfe, Chris D; Beddows, Patricia A; Bouchot, Gerardo Gold; Metcalfe, Tracy L; Li, Hongxia; Van Lavieren, Hanneke

    2011-04-01

    Intensive land development as a result of the rapidly growing tourism industry in the "Riviera Maya" region of the Yucatan Peninsula, Mexico may result in contamination of groundwater resources that eventually discharge into Caribbean coastal ecosystems. We deployed two types of passive sampling devices into groundwater flowing through cave systems below two communities to evaluate concentrations of contaminants and to indicate the possible sources. Pharmaceuticals and personal care products accumulated in the samplers could only have originated from domestic sewage. PAHs indicated contamination by runoff from highways and other impermeable surfaces and chlorophenoxy herbicides accumulated in samplers deployed near a golf course indicated that pesticide applications to turf are a source of contamination. Prevention and mitigation measures are needed to ensure that expanding development does not impact the marine environment and human health, thus damaging the tourism-based economy of the region. Copyright © 2010 Elsevier Ltd. All rights reserved.

  3. Chemical and biological tracers to determine groundwater flow in karstic aquifer, Yucatan Peninsula

    Science.gov (United States)

    Lenczewski, M.; Leal-Bautista, R. M.; McLain, J. E.

    2013-05-01

    Little is known about the extent of pollution in groundwater in the Yucatan Peninsula; however current population growth, both from international tourism and Mexican nationals increases the potential for wastewater release of a vast array of contaminants including personal care products, pharmaceuticals (Rx), and pathogenic microorganisms. Pathogens and Rx in groundwater can persist and can be particularly acute in this region where high permeability of the karst bedrock and the lack of top soil permit the rapid transport of contaminants into groundwater aquifers. The objective of this research is to develop and utilize novel biological and chemical source tracking methods to distinguish between different sources of anthropogenic pollution in degraded groundwater. Although several methods have been used successfully to track fecal contamination sources in small scale studies, little is known about their spatial limitations, as source tracking studies rarely include sample collection over a wide geographical area and with different sources of water. In addition, although source tracking methods to distinguish human from animal fecal contamination are widely available, this work has developed source tracking distinguish between separate human populations is highly unique. To achieve this objective, we collected water samples from a series of drinking wells, cenotes (sinkholes), wastewater treatment plants, and injection wells across the Yucatan Peninsula and examine potential source tracers within the collected water samples. The result suggests that groundwater sources impacted by tourist vs. local populations contain different chemical stressors. This work has developed a more detailed understanding of the presence and persistence of personal care products, pharmaceuticals, and fecal indicators in a karstic system; such understanding will be a vital component for the protection Mexican groundwater and human health. Quantification of different pollution sources

  4. Extensive Gravity Sliding of Late Jurassic-Cretaceous Age along the Northern Yucatan Margin of the Gulf of Mexico

    Science.gov (United States)

    Steier, A.; Mann, P.

    2017-12-01

    Gravity slides on salt or shale detachment surfaces linking updip extension with down dip compression have been described from several margins of the Gulf of Mexico (GOM). In a region 250 km offshore from the southwestern coast of Florida, the late Jurassic section near Destin Dome and Desoto Canyon has undergone late Jurassic to Cretaceous gravity sliding and downdip dispersion of rigid blocks along the top of the underlying Louann salt. Yet there has been no previous study of similar structural styles on the slope and deep basin of its late Jurassic conjugate margin located 200 km offshore of the northern margin of the Yucatan Peninsula. This study describes an extensive area of Mesozoic gravity sliding from the northern Yucatan slope using a grid of 2D seismic data covering a 134,000 km2 area of the northern Yucatan margin tied to nine wells. These data allow the northern Yucatan margin to be divided into three slope and basinal provinces: 1) a 225 km length of the northeastern margin consisting of late Jurassic-Cretaceous section that is not underlain by salt, exhibits no gravity sliding features, and has sub-horizontal dips; 2) a 120 km length of the north-central Yucatan margin with gravity slide features characterized by an 80-km-wide updip zone of normal faults occupying the shelf edge and upper slope and a 50-km-wide downdip zone of folds and thrust faults at the base of the slope; the slide area exhibits multiple detached slide blocks composed of late Jurassic sandstones and marine mudstones separated by intervening salt rollers; growth wedges adjacent to listric, normal faults suggest a gradual and long-lived downdip motion of rigid fault blocks throughout much of the late Jurassic and Cretaceous rather than a catastrophic and instantaneous collapse of the shelf edge; the basal, normal detachment fault averages 3° in dip and is overlain by salt that varies from 0-500 ms in time thickness; by the end of the Cretaceous, most gravity sliding and vertical

  5. The malleability of infant motor development: cautions based on studies of child-rearing practices in Yucatan.

    Science.gov (United States)

    Solomons, H C

    1978-11-01

    Tests with the Bayley Motor Scale were given to 288 infants, equally divided by sex, in Yucatan, Mexico. These were 2 to 54 weeks in age and came from three sociocultural levels. In comparison to USA infants, early acceleration of motor development was followed by a marked downward trend. This phenomenon, if observed in a single child, may indicate progressive neurologic disease. Child-rearing practices would appear to account for the difference in pattern of test performance.

  6. PHENOLOGY AND FRUIT PRODUCTION OF SIRICOTE (Cordia dodecandra A. DC.) PLANTATIONS UNDER THREE KINDS OF MANAGEMENT AT XMATKUIL, YUCATAN, MEXICO

    OpenAIRE

    Simei M. Campos B.; Juan Jiménez-Osornio; Roberto Barrientos M.

    2016-01-01

    Phenology of a species allows us to understand and predict flowering and fructification times useful in the management of deciduous tropical trees. This study was performed in three plantations (P1, P2 and P3) of Cordia dodecandra with different kind of management (P1, pruning, irrigation, weeding; P2, weeding; P3, without management), established in 2002 at Xmatkuil, Yucatan. The evaluation covered the period of September (2011)-August (2012). The phenology was determinated once a month usin...

  7. Nature of the Yucatan Block Basement as Derived From Study of Granitic Clasts in the Impact Breccias of Chicxulub Crater

    Science.gov (United States)

    Vera-Sanchez, P.; Rebolledo-Vieyra, M.; Perez-Cruz, L.; Urrutia-Fucugauchi, J.

    2008-05-01

    The tectonic and petrologic nature of the basement of the Yucatan Block is studied from analyses of basement clasts present in the impact suevitic breccias of Chicxulub crater. The impact breccias have been sampled as part of the drilling projects conducted in the Yucatan peninsula by Petroleos Mexicanos, the National University of Mexico and the Chicxulub Scientific Drilling Project. Samples analyzed come mainly from the Yaxcopoil-1, Tekax, and Santa Elena boreholes, and partly from Pemex boreholes. In this study we concentrate on clasts of the granites, granodiorites and quartzmonzonites in the impact breccias. We report major and trace element geochemical and petrological data, which are compared with data from the granitic and volcanic rocks from the Maya Mountains in Belize and from the Swannee terrane in Florida. Basement granitic clasts analyzed present intermediate to acidic sub-alkaline compositions. Plots of major oxides (e.g., Al2O3, Fe2O3, TiO2 and CaO) and trace elements (e.g., Th, Y, Hf, Nb and Zr) versus silica allow separation of samples into two major groups, which can be compared to units in the Maya Mountains and in Florida basement. The impact suevitic breccia samples have been affected by alteration likely related to the hydrothermal processes associated with the crater melt sheet. Cloritization, seritization and fenitization alterations are recognized, due to the long term hydrothermalism. Krogh et al. (1993) reported U-Pb dates on zircons from the suevitic breccias, which gave dates of 545 +/- 5 Ma and 418 +/- 6 Ma, which were interpreted in terms of the deep granitic metamorphic Yucatan basement. The younger date correlates with the age for the Osceola Granite and the St. Lucie metamorphic complex of the Swannee terrane in the Florida peninsula. The intrusive rocks in the Yucatan basement may be related to approx. 418 Ma ago collisional event in the Late Silurian.

  8. Prevalencia y factores de riesgo en Yucatán, México, para litiasis urinaria Urolithiasis prevalence and risk factors in Yucatan, Mexico

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    Martha Medina-Escobedo

    2002-11-01

    Full Text Available Objetivo. Determinar la prevalencia de urolitiasis en el estado de Yucatán, México, y una posible asociación de ésta con antecedentes familiares de la enfermedad y la dureza del agua. Material y métodos. Durante 1996 se efectuó una encuesta transversal en población abierta mayor de un año de edad, del estado de Yucatán. Los sujetos se clasificaron como litiasis definitiva (LD, litiasis probable (LP y sin litiasis (SL. Se determinó dureza total, dureza de calcio y dureza de magnesio a las muestras de agua empleadas para el consumo humano. Se emplearon ji cuadrada y t de student para comparación de medias de muestras independientes en el análisis. Resultados. De un total de 5 832 encuestas, 323 sujetos (5.5% se catalogaron como LD, y 282 (4.8% como LP. La prevalencia de litiasis se incrementó con la edad, partiendo de 1% en población de 18 años o menor, hasta 11.3% en los mayores de 50. El 44% del grupo LD y 34% del LP tuvieron antecedente familiar de urolitiasis, comparado con 28% del grupo SL (pObjective. To measure the prevalence of urolithiasis in Yucatan, and to establish a possible association of the disease with family history and water hardness. Material and Methods. During 1996, a survey was conducted on the population over one year of age in the State of Yucatan. Subjects were classified as having definite lithiasis (DL, probable lithiasis (PL, or no lithiasis (NL. Total hardness, calcium hardness, and magnesium hardness, were determined in drinking water samples. Results. From a total of 5 832 questionnaires, 323 subjects (5.5% were found to have DL, and 282 (4.8% PL. The prevalence of lithiasis increased sharply with age, ranging from 1% in the population 18 years or younger, to 11.3% in those over 50 years. A family history of urolithiasis was positive in 44% of subjects with DL and in 34 % of those with PL, compared to 28% of those with NL (OR=2.8, 95% CI=2.2-3.4, p<0.0001, and OR=1.8, 95% CI=1.4-2.4, p<0

  9. Ancient shoreline reconstruction at a Maritime Maya Port in Yucatan, Mexico

    Science.gov (United States)

    Jaijel, Roy; Goodman, Beverly; Glover, Jeffrey; Rissolo, Dominique; Beddows, Patricia; Carter, Alice; Smith, Derek; Ben Avraham, Zvi

    2017-04-01

    Throughout history, worldwide, a major part of the human experience has been to adapt to changing landscapes, and environments. These adaptations can take many forms, sometimes as innovation, manipulation of the conditions, behavioral or technological changes; and in some cases the decision to abandon the area. The northeastern Yucatan peninsula, home of the Maritime maya port site Vista-Alegre, shows signs of such human changes, though little is known about the corresponding landscape and environment. Vista Alegre is located on the meeting point of the Caribbean Sea and the Gulf of Mexico, at the north-eastern tip of the Yucatan peninsula, in the back of the Holbox lagoon. The site was inhabited from the 9th century B.C until the mid 16th century A.D., with an apparent two century abandonment phase from the mid 7th to 9th century A.D. A multidisciplinary effort ("Costa Escondida project") has been investigating the life of past Mayan inhabitants and the broader connections of the site to the Maritime Maya trade network. One of the questions that has arisen is what were the mutual influences between the inhabitants to their surrounding environment. In order to answer that question the site's shoreline geomorphology and climate history is being reconstructed for the past 2-3000 years. The reconstruction is based on multiproxy analysis of marine sediment cores and surface samples, combined with archaeological data. The study presented focuses on the shoreline shifts at the site, revealing the complexity, and significant affect of sea level rise on the marine environment of Vista Alegre. This study contributes to our understanding of the site's possible functions, the environmental challenges the local inhabits contended with, and the identification of ancient harboring locations. The results show five depositional phases over the past 2-3000 years. The ancient shoreline maps show a general trend of sea level rise, though with varying rates over time that relates well

  10. Bioeconomic modeling for a small-scale sea cucumber fishery in Yucatan, Mexico.

    Science.gov (United States)

    Hernández-Flores, Alvaro; Cuevas-Jiménez, Alfonso; Poot-Salazar, Alicia; Condal, Alfonso; Espinoza-Méndez, Juan Carlos

    2018-01-01

    Due to the heavy exploitation of holothurians over the last few decades, it is necessary to implement fishing regulations aimed at reversing this situation. Holothurians require specific regulations that take into account their biology and ecology. Their behavior to group and form patches as a strategy for feeding, defense and reproduction, makes them vulnerable to overfishing. The higher the population density, the higher the catchability coefficient, and because they are sedentary organisms, the catchability does not change significantly until the density is very low. Hence, the stock assessment of holothurians can be improved by analyzing their spatial distribution. This paper proposes a stock assessment technique that considers the spatial distribution pattern of the sea cucumber Isostichopus badionotus from Yucatan, Mexico. A bioeconomic spatial model was developed to explain the interactions between fishing effort allocation, quasi-profits and the population in the short term. Because of the high price of the species and the low production costs, artisanal fishers preferred to maximize short-term quasi-profits, rather than the long-term benefits they could gain with low fishing mortality rates.

  11. INFECTION BY Rickettsia felis IN OPOSSUMS (Didelphis sp. FROM YUCATAN, MEXICO

    Directory of Open Access Journals (Sweden)

    Gaspar PENICHE-LARA

    2016-01-01

    Full Text Available Rickettsia felis is an emergent pathogen and the causative agent of a typhus-like rickettsiosis in the Americas. Its transmission cycle involves fleas as biological vectors (mainly Ctenocephalides felis and multiple domestic and synanthropic mammal hosts. Nonetheless, the role of mammals in the cycle of R. felis is not well understood and many efforts are ongoing in different countries of America to clarify it. The present study describes for the first time in Mexico the infection of two species of opossum (Didelphis virginiana and D. marsupialis by R. felis. A diagnosis was carried out from blood samples by molecular methods through the gltAand 17 kDa genes and sequence determination. Eighty-seven opossum samples were analyzed and 28 were found to be infected (32.1% from five out of the six studied localities of Yucatan. These findings enable recognition of the potential epidemiological implications for public health of the presence of infected synanthropic Didelphis in households.

  12. Fish community structure and dynamics in a coastal hypersaline lagoon: Rio Lagartos, Yucatan, Mexico

    Science.gov (United States)

    Vega-Cendejas, Ma. Eugenia; Hernández de Santillana, Mireya

    2004-06-01

    Rio Lagartos, a tropical coastal lagoon in northern Yucatan Peninsula of Mexico, is characterized by high salinity during most of the year (55 psu annual average). Even though the area has been designated as a wetland of international importance because of its great biodiversity, fish species composition and distribution are unknown. To determine whether the salinity gradient was influencing fish assemblages or not, fish populations were sampled seasonally by seine and trawl from 1992 to 1993 and bimonthly during 1997. We identified 81 fish species, eight of which accounted for 53.1% considering the Importance Value Index ( Floridichthys polyommus, Sphoeroides testudineus, Eucinostomus argenteus, Eucinostomus gula, Fundulus majalis, Strongylura notata, Cyprinodon artifrons and Elops saurus). Species richness and density declined from the mouth to the inner zone where extreme salinity conditions are prominent (>80) and competitive interactions decreased. However, in Coloradas basin (53 average sanity) and in the inlet of the lagoon, the highest fish density and number of species were observed. Greater habitat heterogeneity and fish immigration were considered as the best explanation. Multivariate analysis found three zones distinguished by fish occurrence, abundance and distribution. Ichthyofaunal spatial differences were attributed to selective recruitment from the Gulf of Mexico due to salinity gradient and to changing climatic periods. Estuarine and euryhaline marine species are abundant, with estuarine dependent ones entering the system according to environmental preferences. This knowledge will contribute to the management of the Special Biosphere Reserve through baseline data to evaluate environmental and anthropogenic changes.

  13. A survey of zoonotic pathogens carried by house mouse and black rat populations in Yucatan, Mexico.

    Science.gov (United States)

    Panti-May, J A; DE Andrade, R R C; Gurubel-González, Y; Palomo-Arjona, E; Sodá-Tamayo, L; Meza-Sulú, J; Ramírez-Sierra, M; Dumonteil, E; Vidal-Martínez, V M; Machaín-Williams, C; DE Oliveira, D; Reis, M G; Torres-Castro, M A; Robles, M R; Hernández-Betancourt, S F; Costa, F

    2017-08-01

    The house mouse (Mus musculus) and the black rat (Rattus rattus) are reservoir hosts for zoonotic pathogens, several of which cause neglected tropical diseases (NTDs). Studies of the prevalence of these NTD-causing zoonotic pathogens, in house mice and black rats from tropical residential areas are scarce. Three hundred and two house mice and 161 black rats were trapped in 2013 from two urban neighbourhoods and a rural village in Yucatan, Mexico, and subsequently tested for Trypanosoma cruzi, Hymenolepis diminuta and Leptospira interrogans. Using the polymerase chain reaction we detected T. cruzi DNA in the hearts of 4·9% (8/165) and 6·2% (7/113) of house mice and black rats, respectively. We applied the sedimentation technique to detect eggs of H. diminuta in 0·5% (1/182) and 14·2% (15/106) of house mice and black rats, respectively. Through the immunofluorescent imprint method, L. interrogans was identified in 0·9% (1/106) of rat kidney impressions. Our results suggest that the black rat could be an important reservoir for T. cruzi and H. diminuta in the studied sites. Further studies examining seasonal and geographical patterns could increase our knowledge on the epidemiology of these pathogens in Mexico and the risk to public health posed by rodents.

  14. Bioarchaeological investigation of ancient Maya violence and warfare in inland Northwest Yucatan, Mexico.

    Science.gov (United States)

    Serafin, Stanley; Lope, Carlos Peraza; Uc González, Eunice

    2014-05-01

    This study investigates evidence of changes and continuities in ancient Maya violence and warfare in inland northwest Yucatan, Mexico from the Middle Preclassic (600-300 BC) to the Postclassic (AD 1050-1542) through bioarchaeological analysis of cranial and projectile trauma. It is hypothesized that the frequency of violence increases before the Classic Maya collapse and remains high during the Postclassic period. It is also hypothesized that the flat, open terrain was conducive to warfare and resulted in higher trauma frequencies than in other parts of the Maya area. Results show that the frequency of cranial trauma decreases before the Classic collapse and increases in the Postclassic, partially matching the expected chronological trends. The frequency of cranial trauma does not differ significantly from other Maya regions but the pattern does: for all periods, males have more healed injuries than females and they are concentrated on the left side of the anterior of the skull. Some injuries appear to be from small points hafted in wooden clubs. In addition, projectile trauma is evident in a scapula with an embedded arrowhead tip, the first such case reported in a Maya skeleton. Overall, these results suggest greater reliance on open combat and less on raids in this region compared with other parts of the Maya area, possibly due to the flat, open terrain, though the identification of perimortem trauma in both women and men indicates surprise raids on settlements were also practiced. Copyright © 2014 Wiley Periodicals, Inc.

  15. Cytotoxic diterpenes from roots of Crossopetalum gaumeri, a Celastraceae species from Yucatan Peninsula.

    Science.gov (United States)

    Miron-Lopez, Gumersindo; Bazzocchi, Isabel L; Jimenez-Diaz, Ignacio A; Moujir, Laila M; Quijano-Quiñones, Ramiro; Quijano, Leovigildo; Mena-Rejon, Gonzalo J

    2014-05-01

    Four new diterpenes, crossogumerins A-D (1-4) along with six known ones (5-10) were isolated from the root bark of Crossopetalum gaumeri, an endemic medicinal plant from the Yucatan Peninsula. Their structures were elucidated on the basis of 1D and 2D NMR techniques, including HMQC, HMBC, and ROESY experiments. Compounds 1-5, 8-10 were evaluated for cytotoxicity against HeLa (carcinoma of the cervix) and Hep-2 (lung carcinoma) human tumor cells lines and against normal Vero cells (African green monkey kidney) in lag and log phase of growth. Podocarpane diterpenes, crossogumerin B (2) and nimbiol (10), exhibited the highest activity against HeLa cells (IC50 values of 3.1 and 8.1 μM, respectively), but also selectivity on Vero cells (SI 22.6 and 7.5, respectively). The preliminary SAR studies suggest that an epoxy moiety in ring B and a hydrogen bond-donor group strategically positioned in the diterpene core are important requirements for cytotoxicity and selectivity. Copyright © 2014. Published by Elsevier Ltd.

  16. School-based health education in Yucatan, Mexico about the Chikungunya virus and mosquito illness prevention

    Directory of Open Access Journals (Sweden)

    Monica Seungah Choo

    2017-05-01

    Full Text Available The Chikungunya virus (CHIKV has been rapidly spreading throughout Latin America, utilizing pre-existing vectors to infiltrate the immunologically naïve populations. With the current rise of the Zika Virus, there is an urgent need for more rigorous vector control efforts to prevent further Zika breakout. We designed a schoolbased education module on CHIKV and mosquito prevention and presented it to the local students of ages of 6-18 in a rural town called Sudzal in Yucatan, Mexico. We distributed questionnaires before and after education to test the students’ knowledge of CHIKV and mosquito prevention. Chisquared test was performed to determine the efficacy of the presentation in increasing their knowledge. The education presentation has proven to effectively educate the local residents in several critical methods of mosquito prevention, increasing the average test scores by 67% post-education. These include applying repellent, staying hydrated during recuperation, and cleaning indoor water containers to eliminate breeding sites (P<0.001. Furthermore, the questionnaire captured the residents’ behavioral patterns regarding CHIKV and mosquito prevention and identified cultural, ecological, and socioeconomic factors hindering effective implementation of vector control.

  17. Beyond the Colours: Discovering Hidden Diversity in the Nymphalidae of the Yucatan Peninsula in Mexico through DNA Barcoding

    Science.gov (United States)

    Prado, Blanca R.; Pozo, Carmen; Valdez-Moreno, Martha; Hebert, Paul D. N.

    2011-01-01

    Background Recent studies have demonstrated the utility of DNA barcoding in the discovery of overlooked species and in the connection of immature and adult stages. In this study, we use DNA barcoding to examine diversity patterns in 121 species of Nymphalidae from the Yucatan Peninsula in Mexico. Our results suggest the presence of cryptic species in 8 of these 121 taxa. As well, the reference database derived from the analysis of adult specimens allowed the identification of nymphalid caterpillars providing new details on host plant use. Methodology/Principal Findings We gathered DNA barcode sequences from 857 adult Nymphalidae representing 121 different species. This total includes four species (Adelpha iphiclus, Adelpha malea, Hamadryas iphtime and Taygetis laches) that were initially overlooked because of their close morphological similarity to other species. The barcode results showed that each of the 121 species possessed a diagnostic array of barcode sequences. In addition, there was evidence of cryptic taxa; seven species included two barcode clusters showing more than 2% sequence divergence while one species included three clusters. All 71 nymphalid caterpillars were identified to a species level by their sequence congruence to adult sequences. These caterpillars represented 16 species, and included Hamadryas julitta, an endemic species from the Yucatan Peninsula whose larval stages and host plant (Dalechampia schottii, also endemic to the Yucatan Peninsula) were previously unknown. Conclusions/Significance This investigation has revealed overlooked species in a well-studied museum collection of nymphalid butterflies and suggests that there is a substantial incidence of cryptic species that await full characterization. The utility of barcoding in the rapid identification of caterpillars also promises to accelerate the assembly of information on life histories, a particularly important advance for hyperdiverse tropical insect assemblages. PMID:22132140

  18. Beyond the colours: discovering hidden diversity in the Nymphalidae of the Yucatan Peninsula in Mexico through DNA barcoding.

    Directory of Open Access Journals (Sweden)

    Blanca R Prado

    Full Text Available BACKGROUND: Recent studies have demonstrated the utility of DNA barcoding in the discovery of overlooked species and in the connection of immature and adult stages. In this study, we use DNA barcoding to examine diversity patterns in 121 species of Nymphalidae from the Yucatan Peninsula in Mexico. Our results suggest the presence of cryptic species in 8 of these 121 taxa. As well, the reference database derived from the analysis of adult specimens allowed the identification of nymphalid caterpillars providing new details on host plant use. METHODOLOGY/PRINCIPAL FINDINGS: We gathered DNA barcode sequences from 857 adult Nymphalidae representing 121 different species. This total includes four species (Adelpha iphiclus, Adelpha malea, Hamadryas iphtime and Taygetis laches that were initially overlooked because of their close morphological similarity to other species. The barcode results showed that each of the 121 species possessed a diagnostic array of barcode sequences. In addition, there was evidence of cryptic taxa; seven species included two barcode clusters showing more than 2% sequence divergence while one species included three clusters. All 71 nymphalid caterpillars were identified to a species level by their sequence congruence to adult sequences. These caterpillars represented 16 species, and included Hamadryas julitta, an endemic species from the Yucatan Peninsula whose larval stages and host plant (Dalechampia schottii, also endemic to the Yucatan Peninsula were previously unknown. CONCLUSIONS/SIGNIFICANCE: This investigation has revealed overlooked species in a well-studied museum collection of nymphalid butterflies and suggests that there is a substantial incidence of cryptic species that await full characterization. The utility of barcoding in the rapid identification of caterpillars also promises to accelerate the assembly of information on life histories, a particularly important advance for hyperdiverse tropical insect

  19. An epidemiological study of intestinal parasites of dogs from Yucatan, Mexico, and their risk to public health.

    Science.gov (United States)

    Rodríguez-Vivas, Roger Ivan; Gutierrez-Ruiz, Edwin; Bolio-González, Manuel Emilio; Ruiz-Piña, Hugo; Ortega-Pacheco, Antonio; Reyes-Novelo, Enrique; Manrique-Saide, Pablo; Aranda-Cirerol, Francisco; Lugo-Perez, J A

    2011-08-01

    The prevalence of intestinal parasites in dogs and factors associated were studied in a rural community of Yucatan (southern Mexico), with special attention to those gastrointestinal parasites potentially transmitted to man. One hundred thirty dogs from 91 households were studied. Fecal samples were processed by the centrifugation-flotation and the McMaster techniques. To determine factors associated with zoonotic parasites in dogs, univariate analysis was performed, using sex, age, and body condition as independent variables. Variables with p Mexico, with poor body condition had a higher prevalence of intestinal zoonotic parasites as these factors were associated with a higher risk of becoming infected.

  20. A Three-Dimensional Sustainability Evaluation of Jatropha Plantations in Yucatan, Mexico

    Directory of Open Access Journals (Sweden)

    Julio C. Sacramento Rivero

    2016-12-01

    Full Text Available This paper presents a unique sustainability analysis of one of the first attempts to establish a biodiesel industry in Mexico. From 2008, several companies established medium to large-sized Jatropha curcas plantations in Yucatan, hiring local peasants to carry out the agricultural work. After five years, the plantations were abandoned due to poor seed yields and a lack of key knowledge for large-scale cultivation. Based on a multidisciplinary approach, we performed a three-dimensional sustainability evaluation of the potential biodiesel production chain, which included household interviews, a socioeconomic survey, and a life-cycle assessment (LCA. We identified both negative and positive effects in the three dimensions analyzed. Socially and culturally, the local peasant families understood sustainability as their ability to preserve their traditional lifestyle, and associated environmental services with their sense of identity. They therefore considered the jatropha plantations to be positive for sustainability, since they brought income, even though some perceived damage to the natural resources of the surrounding areas. Economically, peasants’ annual household income increased by approximately $1080 USD due to the increased salaries paid by the jatropha companies. The LCA predicted large savings of greenhouse gas emissions (>50% compared to fossil diesel, but also potential negative impacts in some categories (human/ecological toxicity and eutrophication potentials associated with the use of mineral fertilizers, insecticides, and pesticides applied during the cultivation stage. Biodiesel production would be potentially energetically self-sufficient, in addition to producing a 40% energy surplus. Finally, even though the sustainability indicators suggested a positive overall assessment, the reality was that the jatropha projects failed because they were predicated on unrealistically optimistic projections and poor agronomic knowledge of the

  1. Interaction of landscape varibles on the potential geographical distribution of parrots in the Yucatan Peninsula, Mexico

    Directory of Open Access Journals (Sweden)

    Plasencia–Vázquez, A. H.

    2014-12-01

    Full Text Available The loss, degradation, and fragmentation of forested areas are endangering parrot populations. In this study, we determined the influence of fragmentation in relation to vegetation cover, land use, and spatial configuration of fragments on the potential geographical distribution patterns of parrots in the Yucatan Peninsula, Mexico. We used the potential geographical distribution for eight parrot species, considering the recently published maps obtained with the maximum entropy algorithm, and we incorporated the probability distribution for each species. We calculated 71 metrics/variables that evaluate forest fragmentation, spatial configuration of fragments, the ratio occupied by vegetation, and the land use in 100 plots of approximately 29 km², randomly distributed within the presence and absence areas predicted for each species. We also considered the relationship between environmental variables and the distribution probability of species. We used a partial least squares regression to explore patterns between the variables used and the potential distribution models. None of the environmental variables analyzed alone determined the presence/absence or the probability distribution of parrots in the Peninsula. We found that for the eight species, either due to the presence/absence or the probability distribution, the most important explanatory variables were the interaction among three variables, particularly the interactions among the total forest area, the total edge, and the tropical semi–evergreen medium– height forest. Habitat fragmentation influenced the potential geographical distribution of these species in terms of the characteristics of other environmental factors that are expressed together with the geographical division, such as the different vegetation cover ratio and land uses in deforested areas.

  2. Merida and Integrated Strategic Solutions

    Science.gov (United States)

    2011-10-28

    dealt a severe blow to the La Familia Michoacana cartel killing one of its founders and leaders.xlv Several aspects of this successful operation...the leader of La Linea, the armed branch of the Juarez cartel who ordered the killing of a U.S. Consulate employee, was arrested in Mexico City.xci...l ix Mérida Part II. xc Ibid. xci “Report: Leader of La Linea gang arrested in Mexico - CNN”, July 30, 2011

  3. Sources and distribution of organic matter along the Ring of Cenotes, Yucatan, Mexico: sterol markers and statistical approaches.

    Science.gov (United States)

    Derrien, Morgane; Cabrera, Flor Arcega; Tavera, Nadia Libertad Velazquez; Kantún Manzano, Cristian A; Vizcaino, Santiago Capella

    2015-04-01

    The Yucatan Peninsula is a large low lying platform of limestone, dolomite and evaporite deposits, forming an extensive and mature karst aquifer with many sinkholes locally called cenotes. In Yucatan, the only source of drinking water is groundwater and its quality could be impaired by: (i) infiltration of contaminants and (ii) saltwater intrusion. To investigate the sources of organic matter in this aquifer, sediment samples (46) were collected from cenotes and analysed using gas chromatography-mass spectrometry. Sterol analysis, coupled with principal component analysis (PCA), allowed us to distinguish three sources of natural organic matter (e.g. marine, autotrophic and terrigenous) and to detect an anthropogenic input (e.g. fecal contamination). Good consistency was observed between the source assignment and the land use context (forest, agricultural, rural or urban areas) and the season, except for some of the samples where a direct correlation could not be made. The latter cases are most likely a result of the karstic character of the system. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Early results from genetic trials on the growth of Spanish cedar and itssusceptibility to the shoot borer moth in the Yucatan Peninsula, Mexico.

    Science.gov (United States)

    Sheila E. Ward; Kevyn E. Wightman; Bartolo. Rodriguez Santiago

    2008-01-01

    Cedrela odorata (Spanish cedar) is a neotropical broadleaf tree species that is in high demand for furniture and interior fittings. In 1998, seed collections were made from Spanish cedar in the Yucatan Peninsula, Mexico, for genetic conservation and tree improvement projects. Progeny from these collections were established in genetic trials at Bacalar, Noh Bec, and Zoh...

  5. In vitro culture and characterization of putative porcine embryonic germ cells derived from domestic breeds and yucatan mini pig embryos at days 20-24 of gestation

    DEFF Research Database (Denmark)

    Petkov, Stoyan Gueorguiev; Marks, Hendrik; Klein, Tino

    2011-01-01

    Embryonic germ cells (EGC) are cultured pluripotent cells derived from primordial germ cells (PGC). This study explored the possibility of establishing porcine EGC from domestic breeds and Yucatan mini pigs using embryos at Days 17-24 of gestation. In vitro culture of PGC from both pooled...

  6. Geochemical variability of the Yucatan basement: Constraints from crystalline clasts in Chicxulub impactites

    Science.gov (United States)

    Kettrup, B.; Deutsch, A.

    2003-07-01

    The 65 Ma old Chicxulub impact structure with a diameter of about 180 km is again in the focus of the geosciences because of the recently commenced drilling of the scientific well Yaxcopoil- 1. Chicxulub is buried beneath thick post-impact sediments, yet samples of basement lithologies in the drill cores provide a unique insight into age and composition of the crust beneath Yucatan. This study presents major element, Sr, and Nd isotope data for Chicxulub impact melt lithologies and clasts of basement lithologies in impact breccias from the PEMEX drill cores C-1 and Y-6, as well as data for ejecta material from the K/T boundaries at La Lajilla, Mexico, and Furlo, Italy. The impact melt lithologies have an andesitic composition with significantly varying contents of Al, Ca, and alkali elements. Their present day 87Sr/86Sr ratios cluster at about 0.7085, and 143Nd/144Nd ratios range from 0.5123 to 0.5125. Compared to the melt lithologies that stayed inside the crater, data for ejecta material show larger variations. The 87Sr/86Sr ratios range from 0.7081 for chloritized spherules from La Lajilla to 0.7151 for sanidine spherules from Furlo. The 143Nd/144Nd ratio is 0.5126 for La Lajilla and 0.5120 for the Furlo spherules. In an tCHUR(Nd)-tUR(Sr) diagram, the melt lithologies plot in a field delimited by Cretaceous platform sediments, various felsic lithic clasts and a newly found mafic fragment from a suevite. Granite, gneiss, and amphibolite have been identified among the fragments from crystalline basement gneiss. Their 87Sr/86Sr ratios range from 0.7084 to 0.7141, and their 143Nd/144Nd ratios range from 0.5121 to 0.5126. The TNdDM model ages vary from 0.7 to 1.4 Ga, pointing to different source terranes for these rocks. This leads us to believe that the geological evolution and the lithological composition of the Yucatàn basement is probably more complex than generally assumed, and Gondwanan as well as Laurentian crust may be present in the Yucatàn basement.

  7. Paleocene-Eocene Paleoclimatic Event Records in the Chicxulub Crater (Yucatan, Gulf of Mexico)

    Science.gov (United States)

    Perez-Cruz, L. L.; Fucugauchi, J. U.

    2013-05-01

    Chicxulub crater was formed by an asteroid impact on the Yucatan carbonate platform about 65.5 Ma ago at the Cretaceous/Paleogene (K/Pg) boundary. After crater formation, carbonate deposition gradually covered the structure, preserving a largely undisturbed sedimentary record for the Paleogene. As part of the studies, drilling programs with continuous core recovery have been conducted over the past years. The cores preserve a record of post-impact processes, life recovery in target area, platform evolution and emergence, sea-level changes and the paleoceanographic and paleoclimatic conditions in the region. To contribute to the knowledge of the Paleocene-Eocene warming and changes in oceanic hydrography, we carried out x-ray fluorescence and stable oxygen and carbon isotope studies of the carbonate sections on top of the impact breccias sampled in the Santa Elena and Yaxcopoil-1 boreholes. The Santa Elena borehole is located 110 km radial distance from crater center, outside the crater rim. Yaxcopoil-1 borehole is located 62 km away from crater center in the terrace zone inside the crater rim. The Cenozoic sequence is about 332 m and 796 m thick in the Santa Elena and Yaxcopoil-1 boreholes. The stable isotope records are correlated to data on marine sediment cores from the ocean drilling projects for the Paleocene and Eocene, which permit inferences on the paleoceanographic and paleoclimatic reconstruction as well as additional stratigraphic constraints for the sections. The positive bulk carbon isotope (δ13C) values in the basal Paleocene sediments reflect a return or enhancement of ocean productivity following plankton extinctions following the K/Pg impact. The Paleocene represents a time of global warmth temperatures with low vertical and latitudinal gradients in the oceans, likely resulting from elevated CO2 levels. δ13C values in the Santa Elena borehole show increases between 3 and 4 % by the late Paleocene that decrease to levels prevailing before the K

  8. Chicxulub Impact, Yucatan Carbonate Platform, Cretaceous-Paleogene Boundary and Paleocene-Eocene Thermal Maximum

    Science.gov (United States)

    Fucugauchi, J. U.; Perez-Cruz, L. L.

    2015-12-01

    Chicxulub formed 66 Ma ago by an asteroid impact on the Yucatan carbonate platform, southern Gulf of Mexico. Impact produced a 200 km diameter crater, platform fracturing, deformation and ejecta emplacement. Carbonate sedimentation restarted and crater was covered by up to 1 km of sediments. Drilling programs have sampled the Paleogene sediments, which record the changing sedimentation processes in the impact basin and platform. Here, results of a study of the Paleocene-Eocene sediments cored in the Santa Elena borehole are used to characterize the K/Pg and PETM. The borehole reached a depth of 504 m and was continuously cored, sampling the post-impact sediments and impact breccias, with contact at 332 m. For this study, we analyzed the section from ~230 to ~340 m, corresponding to the upper breccias and Paleocene-Eocene sediments. The lithological column, constructed from macroscopic and thin-section petrographic analyses, is composed of limestones and dolomitized limestones with several thin clay layers. Breccias are melt and basement clast rich, described as a suevitic unit. Section is further investigated using paleomagnetic, rock magnetic, X-ray fluorescence geochemical and stable isotope analyses. Magnetic polarities define a sequence of reverse to normal, which correlate to the geomagnetic polarity time scale from chrons 29r to 26r. The d13 C values in the first 20 m interval range from 1.2 to 3.5 %0 and d18 O values range from -1.4 to -4.8 %0. Isotope values show variation trends that correlate with the marine carbon and oxygen isotope patterns for the K-Pg boundary and early Paleocene. Positive carbon isotopes suggest relatively high productivity, with apparent recovery following the K-Pg extinction event. Geochemical data define characteristic trends, with Si decreasing gradually from high values in the suevites, low contents in Paleocene sediments with intervals of higher variability and then increased values likely marking the PETM. Variation trends are

  9. Never judge an iguana by its spines: Systematics of the Yucatan spiny tailed iguana, Ctenosaura defensor (Cope, 1866).

    Science.gov (United States)

    Malone, Catherine L; Reynoso, Víctor Hugo; Buckley, Larry

    2017-10-01

    Spiny tailed iguanas are highly diverse clade of lizards in Mesoamerica, ranging from northern Mexico through Panama. Utilizing 2 regions of mitochondrial DNA (1948bp) and 4 nuclear loci (2232bp) we explored the relationships between these species and the phylogeographic history of the major clades. We discovered that the lineage endemic to the Yucatan Peninsula renders the genus Ctenosaura paraphyletic. To resolve this non-monophyly, we resurrect the taxon Cachryx Cope, 1866, and provide a new diagnosis for the genus. We also find that small body-size and highly spinose tails in the species previously referred to the subgenus Enyaliosaurus, have evolved independently 3 times. Cachryx were recovered as sister to the lineage of iguanines endemic to the Galapagos Islands, and we discuss biogeographic scenarios to explain this relationship as well as those among the primary clades of Ctenosaura in Mesoamerica. Copyright © 2017 Elsevier Inc. All rights reserved.

  10. Water Consumption as Source of Arsenic, Chromium, and Mercury in Children Living in Rural Yucatan, Mexico: Blood and Urine Levels.

    Science.gov (United States)

    Arcega-Cabrera, F; Fargher, L F; Oceguera-Vargas, I; Noreña-Barroso, E; Yánez-Estrada, L; Alvarado, J; González, L; Moo-Puc, R; Pérez-Herrera, N; Quesadas-Rojas, M; Pérez-Medina, S

    2017-10-01

    Studies investigating the correlation between metal content in water and metal levels in children are scarce worldwide, but especially in developing nations. Therefore, this study investigates the correlation between arsenic, chromium, and mercury concentrations in drinking and cooking water and in blood and urine samples collected from healthy and supposedly non-exposed children from a rural area in Yucatan, Mexico. Mercury in water shows concentrations above the recommended World Health Organization (WHO) value for drinking and cooking water. Also, 25% of the children show mercury in urine above the WHO recommended value. Multivariate analyses show a significant role for drinking and cooking water as a vector of exposure in children. Also, the factor analysis shows chronic exposure in the case of arsenic, as well as an ongoing detoxification process through urine in the case of mercury. Further studies should be done in order to determine other potential metal exposure pathways among children.

  11. Copro-necrophagous beetle (Coleoptera: Scarabaeidae diversity in an agroecosystem in Yucatan, Mexico

    Directory of Open Access Journals (Sweden)

    Enrique Reyes Novelo

    2007-03-01

    Full Text Available Scarabaeinae are sensitive to structural habitat changes caused by disturbance. We compared copronecrophagous beetle (Scarabaeinae community structure in three differently managed zones within an agroecosystem of the northern Yucatan Peninsula, Mexico. We placed dung and carrion traps once a month from June 2004 through May 2005. The beetle community included 17 species from the genera Canthon, Canthidium, Deltochilum, Pseudocanthon, Malagoniella, Onthophagus, Phanaeus, Copris, Uroxys, Sisyphus and Ateuchus. The secondary vegetation had a higher beetle diversity than the other two zones. Species richness was highest in the Brosimum alicastrum plantation. The pasture had the lowest species diversity and richness, but exhibited the highest abundance of Scarabaeinae in the dry season. The two zones with extensive tree cover were the most diverse. Roller beetles were dominant over burrower species and small-sized species outnumbered large species. Our data show two important issues: beetle species in the pasture extended their activity to the beginning of the dry season, while abundances dropped in the other, unirrigated zones; and the possibility that the Scarabaeinae living in neotropical forests are opportunistic saprophages and have specialized habits for resources other than dung. The B. alicastrum plantation is beneficial to the entire ranch production system because it functions as a dispersion and development area for stenotopic species limited to tree cover. Rev. Biol. Trop. 55 (1: 83-99. Epub 2007 March. 31.Este estudio describe y compara la estructura de la comunidad de escarabajos copronecrófagos (Scarabaeinae en tres zonas con diferente manejo al interior de un agroecosistema localizado en el norte de la Península de Yucatán. A lo largo de un año de muestreo sistemático se encontraron 17 especies de los géneros Canthon, Canthidium, Deltochilum, Pseudocanthon, Malagoniella, Onthophagus, Phanaeus, Copris, Uroxys, Sisyphus y Ateuchus

  12. Reef demise and back-stepping during the last interglacial, northeast Yucatan

    Science.gov (United States)

    Blanchon, Paul

    2010-06-01

    The elevation of reefs and coastal deposits during the last Interglaciation (MIS-5e) indicates that sea level reached a highstand of as much as 6 m above the present, but it is uncertain how rapidly this level was attained and how it impacted reef development. To investigate this problem, I made a detailed sedimentological analysis of a well-dated reef from the northeast coast of the stable Yucatan Peninsula. Two linear reef tracts were delineated which are offset and at different elevations. The lower reef tract crops out along northern shore for 575 m and extends from below present mean sea level to +3 m. The reef crest facies consists of large Acropora palmata colonies dispersed within a coral boulder-gravel and is flanked by an A. cervicornis-dominated reef-front and a large area of lagoonal framework formed by coalesced patches of A. cervicornis and Montastraea spp. Constituents in the upper centimetre of the lower tract are heavily encrusted by a cap of crustose corallines and, in places, are levelled by a discontinuous marine-erosion surface. The upper reef tract crops out ~150 m inland up to an elevation of +5.8 m and parallels the southern section of shore for ~400 m. It also consist of an A. palmata-dominated crest facies flanked by reef-front, back-reef and lagoonal frameworks. In this case, however, lagoonal frameworks are dominated by a sediment-tolerant assemblage of branching coralline algae. Also different is the lack of encrustation by corallines, and the infiltration of upper tract facies by beach-derived shell-gravels from regressive shoreface deposits above. These results indicate that the lower reef tract and lagoonal patch-reefs formed at a sea level of +3 m. Final capping by crustose corallines and discontinuous marine erosion indicates that the lower tract was terminated by the complete demise of corals on the crest but only patchy demise in the lagoon. Areas of continuous framework accretion between the lagoonal patch reefs and the upper

  13. Diversity of users in banking agencies: An analysis of latent classes, Libertador municipality, Mérida state, Venezuela

    Directory of Open Access Journals (Sweden)

    Marysela Morillo Moreno

    2015-09-01

    Full Text Available To determine the existence of different groups of users of personal services of the banking agencies, based on demographic, psychographic and behavioral characteristics, field research was designed, based on random sampling, in the Libertador municipality of Merida state, Venezuela. As finding, a statistical analysis of latent classes highlights the existence of three classes of users; the kind that brings the largest number of users is characterized by a moderate frequency of use and perception over quality. The identification of such groups precedes the design of marketing practices for each segment, particulary for handling waiting times, service quality recovery.

  14. A maternal Western diet during gestation and lactation modifies offspring's microbiota activity, blood lipid levels, cognitive responses, and hippocampal neurogenesis in Yucatan pigs.

    Science.gov (United States)

    Val-Laillet, David; Besson, Marie; Guérin, Sylvie; Coquery, Nicolas; Randuineau, Gwénaëlle; Kanzari, Ameni; Quesnel, Hélène; Bonhomme, Nathalie; Bolhuis, J Elizabeth; Kemp, Bas; Blat, Sophie; Le Huërou-Luron, Isabelle; Clouard, Caroline

    2017-05-01

    A suboptimal early nutritional environment ( i.e., excess of energy, sugar, and fat intake) can increase susceptibility to diseases and neurocognitive disorders. The purpose of this study was to investigate in nonobese Yucatan minipigs ( Sus scrofa ) the impact of maternal diet [standard diet (SD) vs. Western diet (WD)] during gestation and 25 d of lactation on milk composition, blood metabolism, and microbiota activity of sows ( n = 17) and their piglets ( n = 65), and on spatial cognition ( n = 51), hippocampal plasticity ( n = 17), and food preferences/motivation ( n = 51) in the progeny. Milk dry matter and lipid content, as well as plasma total cholesterol and free fatty acid (FFA) concentrations ( P diet ( P Western diet during gestation and lactation modifies offspring's microbiota activity, blood lipid levels, cognitive responses, and hippocampal neurogenesis in Yucatan pigs. © FASEB.

  15. An optical laser device for mapping 3D geometry of underwater karst structures: first tests in the Ox BelHa system, Yucatan, Mexico; Un dispositivo laser optico para la cartografia 3D de la geometria de estructuras karsticas submarinas: primeros resultados en el sistema de Ox BelHa, Yucatan, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Schiller, A.; Renard, P.

    2016-07-01

    In the course of extended hydrological studies in the coastal Karst plain of Yucatan, near the town of Tulum amongst others, a novel laser scanning device was developed and applied for the acquisition of the 3d-geometry of ground water conduits. The method is derived from similar industrial systems and for the first time adapted to the specific measurement conditions in underwater cave systems. The device projects a laser line over the whole perimeter at a certain position. This line represents the intersection of a plane with the cave walls. The line is imaged with a wide angle camera system. Through proper design and calibration of the device it is possible to derive the true scale geometry of the perimeter via special image processing techniques. By acquiring regularly spaced images it is possible to reconstruct the true scale and 3 d-shape of a tunnel through the incorporation of location and attitude data. In a first test in the Ox Bel Ha under-water cave system, about 800 metres of tunnels have been scanned down to water depths of 20 metres. The raw data is further interpolated using the ODSIM-algorithm in order to delineate the 3D geometry of the cave system. The method provides easy, operable acquisition of the 3-D geometry of caves in clear water with superior resolution and speed and significantly facilitates the measurement in underwater tunnels as well as in dry tunnels. The data gathered represents crucial input to the study of the state, dynamics and genesis of the complex karst water regime. (Author)

  16. Exploration, modelling and management of groundwater-dependent ecosystems in karst – the Sian Ka'an case study, Yucatan, Mexico

    DEFF Research Database (Denmark)

    Gondwe, Bibi Ruth Neuman

    Dette PhD-projekt omhandler afgrænsning af områder, der bidrager med grundvand til grundvandsafhængige økosystemer på Yucatan-halvøen i Mexico. En sådan viden er nyttig, når økosystemerne ønskes beskyttet mod forurening. Yucatan-halvøen i Mexico består af kilometer-tykke kalkstensaflejringer...... på denne ressource, fordi en boomende turisme-industri og kraftigt stigende befolkningstilvækst truer vandkvaliteten. Størstedelen af spildevandet i området bliver ikke renset, og bliver udledt direkte ned i samme ferskvandsressource, som senere skal bruges af mennesker og natur. På Yucatan...... regionalt og internationalt. Sian Ka’an er bl.a. udnævnt til at være en UNESCO Verdensarv lokalitet. Vandet i vådområderne kommer fra grundvandet, men ingen kender udbredelsen af det område, der forsyner grundvand til Sian Ka’an. Det gør det vanskeligt at beskytte denne værdifulde ressource. Gennem...

  17. Is There any Relationship Between the Santa Elena Depression and Chicxulub Impact Crater, Northwestern Yucatan Peninsula, Mexico?

    Science.gov (United States)

    Lefticariu, L.

    2005-05-01

    The Terminal Cretaceous Chicxulub Impact Crater had a strong control on the depositional and diagenetic history of the northern Yucatan Platform during most of the Cenozoic Era. The Chicxulub Sedimentary Basin (henceforth Basin), which approximately coincides with the impact crater, is circumscribed by a concentration of karstic sinkholes known as the Ring of Cenotes. Santa Elena Depression (henceforth Depression) is the name proposed for the bowl-shaped buried feature, first contoured by geophysical studies, immediately south of the Basin, in the area where the Ticul 1 and UNAM 5 wells were drilled. Lithologic, petrographic, and biostratigraphic data on PEMEX, UNAM, and ICDP cores show that: 1) Cenozoic deposits are much thicker inside the Basin than inside the Depression, 2) in general, the Cenozoic formations from inside the Depression are the thickest among those outside the Basin, 3) variably dolomitized pelagic or outer-platform wackestone or mudstone occur both inside the Basin and Depression, 4) the age of the deeper-water sedimentary carbonate rocks is Paleocene-Eocene inside the Basin and Paleocene?-Early Eocene inside the Depression, 5) the oldest formations that crop out are of Middle Eocene age at the edge of the Basin and Early-Middle Eocene age inside the Depression, 6) saline lake deposits, that consist chiefly of anhydrite, gypsum, and fine carbonate, and also contain quartz, chert, clay, zeolite, potassium feldspar, pyrite, and fragments of wood, are present in the Cenozoic section of the UNAM 5 core between 282 and 198 m below the present land surface, 7) the dolomite, subaerial exposure features (subaerial crusts, vugs, karst, dedolomite), and vug-filling cement from the Eocene formations are more abundant inside the Depression than inside the Basin. The depositional environments that are proposed for explaining the Cenozoic facies succession within the Santa Elena Depression are: 1) deeper marine water (Paleocene?-Early Eocene), 2) relatively

  18. Obesidad, morfología corporal y presión arterial en grupos urbanos y rurales de Yucatán Obesity, body morphology, and blood pressure in urban and rural population groups of Yucatan

    Directory of Open Access Journals (Sweden)

    Pedro Arroyo

    2007-08-01

    Full Text Available OBJETIVO: Caracterizar la antropometría y presión arterial de adultos del estado de Yucatán, México. MATERIAL Y MÉTODOS: Se evaluaron diferencias rural-urbanas por grupos sexo-edad en peso, talla, circunferencias de cintura y cadera, y presión arterial en 313 adultos de origen urbano y 271 del rural, de Yucatán. RESULTADOS: No hubo diferencias rural-urbanas en prevalencias de obesidad y sobrepeso, y en hipertensión los urbanos tuvieron valores marginalmente mayores. Se encontró mayor prevalencia rural de cintura anormal sólo en mujeres y hombres jóvenes. La comparación con dos encuestas nacionales y una regional (mixtecos rurales mostró obesidad similar a la notificada en la Encuesta Nacional de Salud 2000 (ENSA y mayor que mixtecos y la informada en la Encuesta Nacional de Enfermedades Crónicas 1993 (ENEC. La prevalencia de cintura anormal fue intermedia entre la indicada en la Encuesta Nacional de Salud y Nutrición 2006 (ENSANUT y mixtecos, y la de hipertensión intermedia entre la notificada en la ENEC y mixtecos. CONCLUSIONES: Las poblaciones maya y mestiza de Yucatán presentaron alta prevalencia de obesidad y cintura anormal que no se acompañaron de prevalencia mayor de hipertensión. Esta observación requiere confirmación.OBJECTIVE: To characterize body morphology and blood pressure of adults of the Mexican state of Yucatan. MATERIAL AND METHODS: Rural-urban differences in weight, height, waist, and hip circumferences, and blood pressure were analyzed in 313 urban and 271 rural subjects. RESULTS: No rural-urban differences in prevalence of obesity and overweight were found. Hypertension was marginally higher in urban subjects. Rural abnormal waist circumference was higher in young men and young women. Comparison with two national surveys and a survey in the aboriginal population (rural mixtecos showed similar prevalence of obesity as ENSA-2000 and higher than mixtecos and ENEC-1993. Abnormal waist circumference was

  19. Hydrogeothermal Convective Circulation Model for the Formation of the Chicxulub Ring of Cenotes in the Yucatan Peninsula, Mexico.

    Science.gov (United States)

    Monroy-Rios, E.; Beddows, P. A.

    2015-12-01

    Despite being deeply buried, the topography and geophysical characteristics of the multi-ring Chicxulub impact structure are reflected on the now subaerial Yucatan Peninsula with aligned arcs of cenotes (sinkholes), forming the "Ring of Cenotes". A pending question is the determination of the geological, geochemical, structural features and associated processes that have led to void development, and the upwards propagation of the voids, cross cutting over 1000 m of super-deposited carbonate sequences. Drawing from the published literature on drill core and geophysical surveys undertaken by Pemex, UNAM, and IODP/ICDP, numerical modeling, and general carbonate platform hydrothermal reactive transport models, we provide a conceptual model for the genesis of the Ring of Cenotes. In horizontally bedded carbonate platforms, geothermal gradients will drive convective flow, with strong vertical components specifically in the platform center. In the Yucatan Platform, a high occurrence of anhydrite and dolomite at depth evokes early burial dolomitization and anhydritization, sourcing Mg from seawater. The Chicxulub impact near the center of the platform produced a low permeability and high thermal conductivity melt rock that arguably extends to the basement rock at 3.5 km below surface. Heat of impact enforced the pre-existing geothermal circulation pattern, and even with depletion of the heat of impact, the high thermal conductivity of the crystalline melt would lead to enhanced geothermal gradients in the center of the platform. The cenotes overlying the crater are deep (150+ m) vertical shafts with most (but not all) breaching the surface. The pit geomorphology suggests a bottom-up formation. Excess Si in the shallow groundwater points to a convective circulation with strong vertical components geochemically linking the granodioritic basement rock to the surface. Water temperature and conductivity profiles support ongoing vertical flux in some deep pit cenotes. Within

  20. High frequency of human blood in Triatoma dimidiata captured inside dwellings in a rural community in the Yucatan Peninsula, Mexico, but low antibody seroprevalence and electrocardiographic findings compatible with Chagas disease in humans.

    Science.gov (United States)

    Monteon, Victor; Alducin, César; Hernández, Jorge; Ramos-Ligonio, Angel; Lopez, Ruth

    2013-03-01

    We studied a small rural community of 411 inhabitants localized in the state of Campeche in the Yucatan Peninsula, Mexico. In 44 collected triatomines captured inside the houses, human feeding source was revealed in 23 of 44 (52%) samples, and chicken feeding source was revealed in 16 of 44 (36%) samples. In a set of 29 triatomines, mouse was the feeding source in 13 (44%) samples, and dog was the feeding source in 7 (24%) samples. Infection index with Trypanosoma cruzi in collected triatomines was 38%, and all parasites belonged to discrete type unit I. Inhabitants referred high contact with triatomine's bite in 60 of 128 (47%) samples, but seroprevalence was 2.3% (3/128). Evidence of electrocardiographic alteration compatible with Chagas disease was observed only in one asymptomatic seropositive subject. In conclusion, Triatoma dimidiata in this region are preferentially infected with T. cruzi I and feed on human beings with relative high frequency, but seroprevalence and Chagas disease in humans is relatively low.

  1. First report of the ectomycorrhizal status of boletes on the Northern Yucatan Peninsula, Mexico determined using isotopic methods.

    Science.gov (United States)

    Hasselquist, Niles J; Douhan, Greg W; Allen, Michael F

    2011-08-01

    Despite their prominent role for tree growth, few studies have examined the occurrence of ectomycorrhizal fungi in lowland, seasonally dry tropical forests (SDTF). Although fruiting bodies of boletes have been observed in a dry tropical forest on the Northern Yucatan Peninsula, Mexico, their occurrence is rare and their mycorrhizal status is uncertain. To determine the trophic status (mycorrhizal vs. saprotrophic) of these boletes, fruiting bodies were collected and isotopically compared to known saprotrophic fungi, foliage, and soil from the same site. Mean δ(15)N and δ(13)C values differed significantly between boletes and saprotrophic fungi, with boletes 8.0‰ enriched and 2.5‰ depleted in (15)N and (13)C, respectively relative to saprotrophic fungi. Foliage was depleted in (13)C relative to both boletes and saprotrophic fungi. Foliar δ(15)N values, on the other hand, were similar to saprotrophic fungi, yet were considerably lower relative to bolete fruiting bodies. Results from this study provide the first isotopic evidence of ectomycorrhizal fungi in lowland SDTF and emphasize the need for further research to better understand the diversity and ecological importance of ectomycorrhizal fungi in these forested ecosystems.

  2. CHICKEN COOPS, Triatoma dimidiata INFESTATION AND ITS INFECTION WITH Trypanosoma cruzi IN A RURAL VILLAGE OF YUCATAN, MEXICO

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    Edgar KOYOC-CARDEÑA

    2015-06-01

    Full Text Available This study longitudinally investigated the association between Triatoma dimidiata infestation, triatomine infection with Trypanosoma cruzi and household/backyard environmental characteristics in 101 homesteads in Molas and Yucatan, Mexico, between November 2009 (rainy season and May 2010 (dry season. Logistic regression models tested the associations between insect infestation/infection and potential household-level risk factors. A total of 200 T. dimidiata were collected from 35.6% of the homesteads, mostly (73% from the peridomicile. Of all the insects collected, 48% were infected with T. cruzi. Infected insects were collected in 31.6% of the homesteads (54.1% and 45.9% intra- and peridomiciliary, respectively. Approximately 30% of all triatomines collected were found in chicken coops. The presence of a chicken coop in the backyard of a homestead was significantly associated with both the odds of finding T. dimidiata (OR = 4.10, CI 95% = 1.61-10.43, p = 0.003 and the presence of triatomines infected with T. cruzi (OR = 3.37, CI 95% = 1.36-8.33, p = 0.006. The results of this study emphasize the relevance of chicken coops as a putative source of T. dimidiata populations and a potential risk for T. cruzi transmission.

  3. Development and Calibration of a Model for the Determination of Hurricane Wind Speed Field at the Peninsula of Yucatan

    Directory of Open Access Journals (Sweden)

    L.E. Fernández–Baqueiro

    2009-01-01

    Full Text Available In this work a model to calculate the wind speed field produced by hurricanes that hit the Yucatan Peninsula is developed. The model variables are calculated using equations recently developed, that include new advances in meteorology. The steps in the model are described and implemented in a computer program to systematize and facilitate the use of this model. The model and the program are calibrated using two data bases; the first one includes trajectories and maximum wind velocities of hurricanes; the second one includes records of wind velocities obtained from the Automatic Meteorology Stations of the National Meteorology Service. The hurricane wind velocity field is calculated using the model and information of the first data base. The model results are compared with field data from the second data base. The model is calibrated adjusting the Holland's pressure radial profile parameter B; this is carried out for three hurricane records: Isidore, Emily and Wilma. It is concluded that a value of B of 1.3 adjusts globally the three hurricane records and that the developed model is capable of reproducing satisfactorily the wind velocity records.

  4. Fishery of the Goliath grouper, Epinephelus itajara (Teleostei: Epinephelidae) based on local ecological knowledge and fishery records in Yucatan, Mexico.

    Science.gov (United States)

    Aguilar-Perera, Alfonso; González-Salas, Carlos; Tuz-Sulub, Armin; Villegas-Hernández, Harold

    2009-09-01

    The Goliath grouper, Epinephelus itajara, a large-bodied (approximately 2.5 m TL, > 400 kg) and critically endangered fish (Epinephelidae), is highly vulnerable to overfishing. Although protected from fishing in many countries, its exploitation in Mexico is unregulated; a situation that puts its populations at risk. Fishery records of E. itajara are scarce, which prevents determination of its fishery status. This work aimed to elucidate the E. itajara fishery in the northern Yucatan Peninsula by 1) analyzing available catch records and 2) interviewing veteran fishermen (local ecological knowledge) from two traditional landing sites: Dzilam de Bravo and Puerto Progreso. Historic fishery records from two fishing cooperatives were analyzed in order to elucidate the current situation and offer viable alternatives for conservation and management. Catches have decreased severely. Local knowledge obtained from fishermen represented a very important source of information for reconstructing the fisheries history of this species. Conservation measures that incorporate regional and international regulations on critically endangered fish species are suggested.

  5. Two new species of dicyemid mesozoans (Dicyemida: Dicyemidae) from Octopus maya Voss & Solis-Ramirez (Octopodidae) off Yucatan, Mexico.

    Science.gov (United States)

    Castellanos-Martinez, Sheila; Aguirre-Macedo, M Leopoldina; Furuya, Hidetaka

    2016-07-01

    Two new dicyemid species are described from the endemic cephalopod Octopus maya Voss & Solis-Ramirez collected off Yucatan, Mexico. The renal sacs of 40 juvenile and adult octopuses from four localities were examined. Dicyema hochbergi n. sp. is a medium-sized species that reaches 2,245 µm in length. The vermiform stages consist of 18-24 peripheral cells, a conical calotte and the extension of the axial cell between the base and middle of the metapolar cells. Infusoriform embryos consist of 39 cells with urn cell containing one germinal cell, two nuclei and solid refringent bodies. Dicyema mexcayae n. sp. is a relatively small species that reaches 1,114 µm in length. The vermiform stages are constituted by 14-16 peripheral cells, an elongate calotte and the axial cell extending forward to the middle of the metapolar cells. The infusoriform embryos consist of 37 cells, two solid refringent bodies and urn cells with two nuclei each. The present study represents the first description of a dicyemid species from O. maya and increases the number of described species from Mexican waters to 11.

  6. Effects of precipitation regime and soil nitrogen on leaf traits in seasonally dry tropical forests of the Yucatan Peninsula, Mexico.

    Science.gov (United States)

    Roa-Fuentes, Lilia L; Templer, Pamela H; Campo, Julio

    2015-10-01

    Leaf traits are closely associated with nutrient use by plants and can be utilized as a proxy for nutrient cycling processes. However, open questions remain, in particular regarding the variability of leaf traits within and across seasonally dry tropical forests. To address this, we considered six leaf traits (specific area, thickness, dry matter content, N content, P content and natural abundance (15)N) of four co-occurring tree species (two that are not associated with N2-fixing bacteria and two that are associated with N2-fixing bacteria) and net N mineralization rates and inorganic N concentrations along a precipitation gradient (537-1036 mm per year) in the Yucatan Peninsula, Mexico. Specifically we sought to test the hypothesis that leaf traits of dominant plant species shift along a precipitation gradient, but are affected by soil N cycling. Although variation among different species within each site explains some leaf trait variation, there is also a high level of variability across sites, suggesting that factors other than precipitation regime more strongly influence leaf traits. Principal component analyses indicated that across sites and tree species, covariation in leaf traits is an indicator of soil N availability. Patterns of natural abundance (15)N in foliage and foliage minus soil suggest that variation in precipitation regime drives a shift in plant N acquisition and the openness of the N cycle. Overall, our study shows that both plant species and site are important determinants of leaf traits, and that the leaf trait spectrum is correlated with soil N cycling.

  7. Eco-bio-social determinants for house infestation by non-domiciliated Triatoma dimidiata in the Yucatan Peninsula, Mexico.

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    Eric Dumonteil

    Full Text Available BACKGROUND: Chagas disease is a vector-borne disease of major importance in the Americas. Disease prevention is mostly limited to vector control. Integrated interventions targeting ecological, biological and social determinants of vector-borne diseases are increasingly used for improved control. METHODOLOGY/PRINCIPAL FINDINGS: We investigated key factors associated with transient house infestation by T. dimidiata in rural villages in Yucatan, Mexico, using a mixed modeling approach based on initial null-hypothesis testing followed by multimodel inference and averaging on data from 308 houses from three villages. We found that the presence of dogs, chickens and potential refuges, such as rock piles, in the peridomicile as well as the proximity of houses to vegetation at the periphery of the village and to public light sources are major risk factors for infestation. These factors explain most of the intra-village variations in infestation. CONCLUSIONS/SIGNIFICANCE: These results underline a process of infestation distinct from that of domiciliated triatomines and may be used for risk stratification of houses for both vector surveillance and control. Combined integrated vector interventions, informed by an Ecohealth perspective, should aim at targeting several of these factors to effectively reduce infestation and provide sustainable vector control.

  8. Eco-bio-social determinants for house infestation by non-domiciliated Triatoma dimidiata in the Yucatan Peninsula, Mexico.

    Science.gov (United States)

    Dumonteil, Eric; Nouvellet, Pierre; Rosecrans, Kathryn; Ramirez-Sierra, Maria Jesus; Gamboa-León, Rubi; Cruz-Chan, Vladimir; Rosado-Vallado, Miguel; Gourbière, Sébastien

    2013-01-01

    Chagas disease is a vector-borne disease of major importance in the Americas. Disease prevention is mostly limited to vector control. Integrated interventions targeting ecological, biological and social determinants of vector-borne diseases are increasingly used for improved control. We investigated key factors associated with transient house infestation by T. dimidiata in rural villages in Yucatan, Mexico, using a mixed modeling approach based on initial null-hypothesis testing followed by multimodel inference and averaging on data from 308 houses from three villages. We found that the presence of dogs, chickens and potential refuges, such as rock piles, in the peridomicile as well as the proximity of houses to vegetation at the periphery of the village and to public light sources are major risk factors for infestation. These factors explain most of the intra-village variations in infestation. These results underline a process of infestation distinct from that of domiciliated triatomines and may be used for risk stratification of houses for both vector surveillance and control. Combined integrated vector interventions, informed by an Ecohealth perspective, should aim at targeting several of these factors to effectively reduce infestation and provide sustainable vector control.

  9. Use of enzyme linked immunosorbent assay (ELISA) for the diagnosis of brucellosis in cattle in Yucatan, Mexico

    International Nuclear Information System (INIS)

    Dajer, A.; Gutierrez, E.; Zapata, D.

    1998-01-01

    Sera (247) from non-vaccinated brucellosis negative herds, 328 negative sera from Brucella abortus strain 19 vaccinated herds (brucellosis free), and 95 sera positive to the Rose Bengal test (RBT) and Complement Fixation test (CFT) from Brucella abortus-infected herds, were used to determine the relative sensitivity and specificity of a FAO/IAEA I-ELISA kit and the Rivanol Agglutination Test (RAT), using the CFT as a 'gold standard'. A threshold value for the I-ELISA was determined to be 37 PP using the mean plus 3 standard deviations of the negative sera from vaccinated animals. The I-ELISA showed a high relative sensitivity (100%) and a good relative specificity (92.5%), using the threshold determined for local conditions. The RAT gave a lower sensitivity value than the CFT (97.8%) and good specificity (99.3%). The I-ELISA could be used as a screening test under Yucatan conditions or as a confirmatory test in places where vaccination is not carried out. The RAT lacks sensitivity and is therefore not recommended for use in final stages of eradication programs but could be used in control programmes or early stages of eradication campaigns as a confirmatory test. (author)

  10. Eco-Bio-Social Determinants for House Infestation by Non-domiciliated Triatoma dimidiata in the Yucatan Peninsula, Mexico

    Science.gov (United States)

    Dumonteil, Eric; Nouvellet, Pierre; Rosecrans, Kathryn; Ramirez-Sierra, Maria Jesus; Gamboa-León, Rubi; Cruz-Chan, Vladimir; Rosado-Vallado, Miguel; Gourbière, Sébastien

    2013-01-01

    Background Chagas disease is a vector-borne disease of major importance in the Americas. Disease prevention is mostly limited to vector control. Integrated interventions targeting ecological, biological and social determinants of vector-borne diseases are increasingly used for improved control. Methodology/principal findings We investigated key factors associated with transient house infestation by T. dimidiata in rural villages in Yucatan, Mexico, using a mixed modeling approach based on initial null-hypothesis testing followed by multimodel inference and averaging on data from 308 houses from three villages. We found that the presence of dogs, chickens and potential refuges, such as rock piles, in the peridomicile as well as the proximity of houses to vegetation at the periphery of the village and to public light sources are major risk factors for infestation. These factors explain most of the intra-village variations in infestation. Conclusions/significance These results underline a process of infestation distinct from that of domiciliated triatomines and may be used for risk stratification of houses for both vector surveillance and control. Combined integrated vector interventions, informed by an Ecohealth perspective, should aim at targeting several of these factors to effectively reduce infestation and provide sustainable vector control. PMID:24086790

  11. Opportunities for improved chagas disease vector control based on knowledge, attitudes and practices of communities in the yucatan peninsula, Mexico.

    Directory of Open Access Journals (Sweden)

    Kathryn Rosecrans

    2014-03-01

    Full Text Available Chagas disease is a vector-borne parasitic disease of major public health importance. Current prevention efforts are based on triatomine vector control to reduce transmission to humans. Success of vector control interventions depends on their acceptability and value to affected communities. We aimed to identify opportunities for and barriers to improved vector control strategies in the Yucatan peninsula, Mexico.We employed a sequence of qualitative and quantitative research methods to investigate knowledge, attitudes and practices surrounding Chagas disease, triatomines and vector control in three rural communities. Our combined data show that community members are well aware of triatomines and are knowledgeable about their habits. However, most have a limited understanding of the transmission dynamics and clinical manifestations of Chagas disease. While triatomine control is not a priority for community members, they frequently use domestic insecticide products including insecticide spray, mosquito coils and plug-in repellents. Families spend about $32 US per year on these products. Alternative methods such as yard cleaning and window screens are perceived as desirable and potentially more effective. Screens are nonetheless described as unaffordable, in spite of a cost comparable to the average annual spending on insecticide products.Further education campaigns and possibly financing schemes may lead families to redirect their current vector control spending from insecticide products to window screens. Also, synergism with mosquito control efforts should be further explored to motivate community involvement and ensure sustainability of Chagas disease vector control.

  12. Can antibiotic resistance analysis be a useful tool for tracking population sources of contamination in Yucatan groundwater?

    Science.gov (United States)

    McLain, J. E.; Lenczewski, M.; Leal-Bautista, R. M.

    2013-05-01

    Antibiotic resistance patterns have been widely used in scientific studies conducted to identify sources of water contamination. However, the methods of resistance determination have not been standardized; therefore, the data on antibiotic resistance in the environment come from studies that have used a range of media types, antibiotic concentrations, and incubation periods, making it difficult to compare results between environments. Over two years, we assessed antibiotic sensitivity of Gram-positive and Gram-negative bacteria isolated from Yucatan water sources, to identify unique resistance patterns and assess the potential for antibiotic resistance analysis as a tool to discriminate between fecal pollution from two population sources (tourist and local). Though resistance to erythromycin, streptomycin, and ciprofloxacin showed some differences between populations, natural bacterial resistance (in isolates from pristine sources) was very high and confounded the research findings. This study highlights the need among the research community involved in tracking of environmental antibiotic resistance to develop a standardized and rigorously validated suite of methods that address background resistance and that can be used across environments, to accurately inform source tracking studies.

  13. Young Mexicans' hopes and fears about abortion and abortion law: a qualitative study in two cities.

    Science.gov (United States)

    Tatum, Carrie E; Garcia, Sandra G; Yam, Eileen A; Becker, Davida

    2006-01-01

    In Mexico, abortion is legal only in limited, specific circumstances and unsafe abortion complications are estimated to be the fourth leading cause of maternal mortality. Our study sought to understand the opinions Mexicans hold about abortion and sexuality and to learn about their fears and hopes about more liberalized abortion laws in Mexico. We carried out 12 focus groups with a total of 87 women and men, aged 18-24. Six focus groups took place in Mexico City and six in Merida, Yucatan. One reader thematically analyzed and coded discussion transcripts. Participants favoring highly restrictive abortion laws generally felt that pregnant women should "face the consequences" of having a baby, whereas those who favored less restrictive laws focused less on culpability and more on the woman's right to control her future. Mexico City participants generally had more liberal abortion opinions. Most Merida participants thought abortion was never legal, despite the fact that their state has the country's most liberal abortion laws. Many felt that, if abortion were legal, there would be more abortions but that it would likely be a safer procedure. Merida participants' more conservative attitudes may be a reflection of their lower educational levels and largerproportion of Catholic participants compared to the Mexico City groups. It is critical to introduce more balanced information that emphasizes the safety of abortions performed under legal conditions and address fears of greatly elevated abortion rates if abortion laws were liberalized. Mexican young adults need more scientific, balanced sources of information on abortion and abortion law.

  14. Modelling dengue fever risk in the State of Yucatan, Mexico using regional-scale satellite-derived sea surface temperature.

    Science.gov (United States)

    Laureano-Rosario, Abdiel E; Garcia-Rejon, Julian E; Gomez-Carro, Salvador; Farfan-Ale, Jose A; Muller-Karger, Frank E

    2017-08-01

    Accurately predicting vector-borne diseases, such as dengue fever, is essential for communities worldwide. Changes in environmental parameters such as precipitation, air temperature, and humidity are known to influence dengue fever dynamics. Furthermore, previous studies have shown how oceanographic variables, such as El Niño Southern Oscillation (ENSO)-related sea surface temperature from the Pacific Ocean, influences dengue fever in the Americas. However, literature is lacking on the use of regional-scale satellite-derived sea surface temperature (SST) to assess its relationship with dengue fever in coastal areas. Data on confirmed dengue cases, demographics, precipitation, and air temperature were collected. Incidence of weekly dengue cases was examined. Stepwise multiple regression analyses (AIC model selection) were used to assess which environmental variables best explained increased dengue incidence rates. SST, minimum air temperature, precipitation, and humidity substantially explained 42% of the observed variation (r 2 =0.42). Infectious diseases are characterized by the influence of past cases on current cases and results show that previous dengue cases alone explained 89% of the variation. Ordinary least-squares analyses showed a positive trend of 0.20±0.03°C in SST from 2006 to 2015. An important element of this study is to help develop strategic recommendations for public health officials in Mexico by providing a simple early warning capability for dengue incidence. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Hydrochemistry of waters from five cenotes and evaluation of their suitability for drinking-water supplies, northeastern Yucatan, Mexico

    Science.gov (United States)

    Alcocer, Javier; Lugo, Alfonso; Marín, Luis E.; Escobar, Elva

    Waters from five cenotes that are currently being used for aquatic recreational activities and that lie along the Cancun-Tulum touristic corridor, Mexico, were evaluated hydrochemically to determine whether the cenotes may be considered as potential drinking-water sources. Several parameters exceed the Mexican Drinking Water Standards (MDWS), but since they do not pose a significant health threat, four of the five cenotes may be used as drinking-water sources. The common contaminants in the Yucatan Peninsula, fecal coliforms and nitrate, are in most cases below the MDWS (0-460 MPN/100ml and 0.31-1.18mg/L, respectively). Although these four cenotes meet the MDWS, a careful groundwater management policy needs to be developed to avoid contamination (fecal and nitrates) and salt-water intrusion. Résumé Les eaux de cinq cénotés, qui sont normalement utilisées pour des activités de plein air, dans la région touristique de Cancun-Tulum (Mexique), ont été soumises à analyses chimiques pour savoir si les cénotés peuvent être considérés comme des sources d'eau potable. Plusieurs paramètres dépassent les normes mexicaines en matière d'eau potable; mais comme ceux-ci ne posent pas de problème réel de santé, quatre des cinq cénotés peuvent être captés pour l'eau potable. Les contaminants habituels dans les eaux de la presqu'île du Yucatan, coliformes fécaux et concentrations élevées en nitrate, sont la plupart du temps au-dessous des normes (respectivement 0 à 460 germes/100ml et 0,31 à 1,18mg/l). Bien que ces quatre cénotés satisfassent aux normes, il est nécessaire de mettre en place des règles précises de l'utilisation de l'eau souterraine, afin d'éviter la contamination par les germes fécaux et par les nitrates, ainsi que l'intrusion marine. Resumen Se analizó hidroquímica y bacteriológicamente el agua de algunos cenotes localizados a lo largo del corredor turístico Cancun-Tulum, que actualmente se utilizan para diversas actividades

  16. Comparison of changes over time in leukocyte counts in Yucatan minipigs irradiated with simulated solar particle event-like radiation

    Science.gov (United States)

    Sanzari, Jenine K.; Steven Wan, X.; Muehlmatt, Amy; Lin, Liyong; Kennedy, Ann R.

    2015-01-01

    During a major solar particle event (SPE), astronauts in space are at risk of exposure to an increased dose of proton radiation. The whole body distribution of the absorbed SPE proton dose is inhomogeneous, and such an inhomogeneous SPE proton dose can be simulated by electron radiation. Using Yucatan minipigs as an animal model, we compared the time courses of leukocyte count changes after exposure to proton simulated SPE (pSPE) radiation or electron simulated SPE (eSPE) radiation. The results demonstrated that the time required after irradiation to reach the lowest leukocyte counts was generally comparable between the pSPE and eSPE radiation exposures. However, the leukocyte count often recovered faster after electron irradiation compared to proton irradiation at the corresponding doses. In addition, the radiation dose required to achieve comparable magnitudes of leukocyte count decrease was higher in the eSPE animals than for the pSPE animals. In conclusion, based on the magnitude of the decrease and the time required to reach the lowest leukocyte counts after irradiation, the pSPE radiation was more effective than the eSPE radiation in reducing the peripheral leukocyte counts. Lymphocytes appeared to be the most sensitive type of leukocytes in response to either type of SPE radiation. It is particularly noteworthy that following exposure to pSPE radiation at the skin doses >5 Gy, the neutrophils do not recover from the radiation damage at times up to 30 days, and the neutrophils have not recovered to their baseline levels even at 90 days post-irradiation. These results suggest a marked difference in the ability of the neutrophils to recover from pSPE radiation compared with the results observed for eSPE radiation.

  17. PHENOLOGY AND FRUIT PRODUCTION OF SIRICOTE (Cordia dodecandra A. DC. PLANTATIONS UNDER THREE KINDS OF MANAGEMENT AT XMATKUIL, YUCATAN, MEXICO

    Directory of Open Access Journals (Sweden)

    Simei M. Campos B.

    2016-03-01

    Full Text Available Phenology of a species allows us to understand and predict flowering and fructification times useful in the management of deciduous tropical trees. This study was performed in three plantations (P1, P2 and P3 of Cordia dodecandra with different kind of management (P1, pruning, irrigation, weeding; P2, weeding; P3, without management, established in 2002 at Xmatkuil, Yucatan. The evaluation covered the period of September (2011-August (2012. The phenology was determinated once a month using Fournier method. Production was assessed by harvesting and counting all fruit of all trees from each orchard and fruit quality was weighed and measured the length and width of a sample (n = 20 and obtained the moisture content of the same putting them in a dryer at 60°C. Results showed that P1 presented 100% leaves in September 2011, and during the period November 2011- August 2012. The percentage of leaves decreased to 25% only in the month of October 2011. P2 y P3 lost all their leaves during the period December-March. Regarding flowering, P1 presented flowers in percentage of 25% most of the year except for the months of June and July when the presence of any floral structure was recorded. The peak was observed in March. The other two plantations, P2 and P3, bloomed during the dry season (December to May. P2 presented a peak in February and P3 in March. Fructification in P1 showed in the months of October, November and January but the maximum production was in May, P2 in the months of January to June, showing a peak in March and P3 from February to May with a maximum in the month of May. The highest production and fruit quality was recorded in P1.

  18. The Disruption of Subsistence Agricultural Systems in Rural Yucatan, Mexico may have Contributed to the Coexistence of Stunting in Children with Adult Overweight and Obesity.

    Science.gov (United States)

    Gurri, Francisco D

    2015-12-01

    This paper attempts to link last century's disruption of local agricultural systems to today's presence of childhood under nutrition and adult overweight and obesity in the Yucatan Peninsula. It first compares Height for Age (H/A), Weight for Age (W/A) and Body Mass Index (BMI) of children from three rural populations in Yucatan and Campeche, Mexico whose subsistence strategy had been altered to different degrees since 1970. It then compares BMI in adults, in the same regions, born before and after the alteration of their environment in the 1970's. Children in the least disrupted zone were taller and had lower BMI than children in the other two, but were not heavier than children from the richest disrupted zone. Children in the poorest disrupted zone were shorter and lighter than the rest. BMI in adult men was higher in the two most disrupted zones only in those cohorts that grew up after the traditional agricultural regime was altered. It is concluded that disruptions of staple-based subsistence agriculture promoted a stockier phenotype in children and a tendency to accumulate body fat. Persistence of these conditions in the twenty first century has favored the coexistence of stunting during childhood with adults who easily become overweight.

  19. Price, Virtues, Principles: How to Discern What Inspires Best Practices in Water Management? A Case Study about Small Farmers in the Yucatan Peninsula of Mexico

    Directory of Open Access Journals (Sweden)

    Rafael R. Ramírez

    2016-04-01

    Full Text Available Improving water practices among small farmers in a water scarce area like the Yucatan Peninsula in Mexico is a complex task. Despite government attempts to enforce regulations and question the possibility of adjusting prices, the misuse of this scarce resource continues. Most farmers are, at best, motivated to aim for a minimum level of compliance, with very few striving to engage in best practices. This article seeks to make a proposal about the best drivers for inspiring best practices in an effort to improve the use of water management in the area. It proposes that a virtue ethics approach that explicitly focuses on the cultivation of an attitude of respect for water founded on three key principles (participation, hydrosolidarity and proactive engagement is the best solution for Yucatan. This hypothesis is the result of developing a singular methodology based on Partial Least Squares (PLS, according to structural equation modeling (SEM, that could be replicated anywhere to ascertain which measures are best suited in a particular context. Using a small sample size, this research ascertains what is required to achieve best practices with regards to the management of water in that particular area.

  20. [Prevalence of high blood pressure and their association with body mass index in children between 5 and 11 years of Nahbalam, Yucatan].

    Science.gov (United States)

    Saury-Paredes, Leonel Alejandro

    To determine the prevalence of high blood pressure in children aged between 5-11 years in the community of Nahbalam, Yucatan, and its association with the body mass index. A transversal study with children of the primary school "Lazaro Cardenas del Rio" was performed, measuring blood pressure, height, and weight of 259 girls and boys; systolic and/or diastolic blood pressure equal or greater than percentile 95 for gender, age, and height at three measures was considered as hypertension; prehypertension was considered as blood pressure equal or greater than percentile 90 but lower than percentile 95. A prevalence of 11.9% prehypertension and 6.1% hypertension was found. There is an association between hypertension and overweight and obesity (p ≤ 0.001). The prevalence of high blood pressure in children of the community of Nahbalam, Yucatan, is 18%. The children with overweight and obesity have an almost tenfold greater risk of hypertension than the eutrophic children (OR: 9.896; 95% CI: 2.738-35.764).

  1. Planktonic cyanobacteria of the tropical karstic lake Lagartos from the Yucatan Peninsula, Mexico.

    Science.gov (United States)

    Valadez, Francisco; Rosiles-González, Gabriela; Almazán-Becerril, Antonio; Merino-Ibarra, Martin

    2013-06-01

    The tropical karstic lakes on the Mexican Caribbean Sea coast are numerous. However, there is an enormous gap of knowledge about their limnological conditions and micro-algae communities. In the present study, surface water samples were collected monthly from November 2007 to September 2008 to provide taxonomical composition and biovolume of planktonic cyanobacteria of the lake Lagartos from State of Quintana Roo, Mexico. Water temperature, pH, conductivity, salinity, soluble reactive phosphorus (SRP), dissolved inorganic nitrogen (DIN), and soluble reactive silica (SRSi) levels were also analyzed. A total of 22 species were identified. Chroococcales and Oscillatoriales dominated the phytoplankton assemblages during the study period. Chroococcus pulcherrimus, Coelosphaerium confertum, Cyanodyction iac, Phormidium pachydermaticum and Planktolyngbya contorta were recorded for the first time in Mexico. A surplus of DIN (mean value of 42.7 microM) and low concentrations of SRP (mean value of 1.0 microM) promoted the enhanced growth and bloom formation of cyanobacteria. The mean biovolume was 3.22 x 10(8) microm3/mL, and two biovolume peaks were observed; the first was dominated by Microcystis panniformis in November 2007 (7.40 x 10(8) microm3/mL), and the second was dominated by Oscillatoriaprinceps in April 2008 (6.55 x 10(8) microm3/mL). Water quality data, nitrates enrichment, and trophic state based on biovolume, indicated that Lagartos is a hyposaline, secondarily phosphorus-limited, and eutrophic lake, where the cyanobacteria flora was composed mainly by non-heterocystous groups.

  2. Planktonic Cyanobacteria of the tropical karstic lake Lagartos from the Yucatan Peninsula, Mexico

    Directory of Open Access Journals (Sweden)

    Francisco Valadez

    2013-06-01

    Full Text Available The tropical karstic lakes on the Mexican Caribbean Sea coast are numerous. However, there is an enormous gap of knowledge about their limnological conditions and micro-algae communities. In the present study, surface water samples were collected monthly from November 2007 to September 2008 to provide taxonomical composition and biovolume of planktonic cyanobacteria of the lake Lagartos from State of Quintana Roo, Mexico. Water temperature, pH, conductivity, salinity, soluble reactive phosphorus (SRP, dissolved inorganic nitrogen (DIN, and soluble reactive silica (SRSi levels were also analyzed. A total of 22 species were identified. Chroococcales and Oscillatoriales dominated the phytoplankton assemblages during the study period. Chroococcus pulcherrimus, Coelosphaerium confertum, Cyanodyction iac, Phormidium pachydermaticum and Planktolyngbya contorta were recorded for the first time in Mexico. A surplus of DIN (mean value of 42.7µM and low concentrations of SRP (mean value of 1.0µM promoted the enhanced growth and bloom formation of cyanobacteria. The mean biovolume was 3.22X10(8µm³/mL, and two biovolume peaks were observed; the first was dominated by Microcystis panniformis in November 2007 (7.40X10(8µm³/mL, and the second was dominated by Oscillatoria princeps in April 2008 (6.55X10(8µm³/mL. Water quality data, nitrates enrichment, and trophic state based on biovolume, indicated that Lagartos is a hyposaline, secondarily phosphorus-limited, and eutrophic lake, where the cyanobacteria flora was composed mainly by non-heterocystous groups.

  3. Elasmopus yucalpeten sp. n. (Crustacea, Amphipoda, Maeridae from the northern Yucatan coast, with a key for the genus in the Gulf of Mexico and biogeographic comments

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    Carlos Paz Ríos

    2014-10-01

    Full Text Available A new amphipod species of the genus Elasmopus Costa, 1853 is described and illustrated based on material collected in a harbor on the northern Yucatan coast, southern Gulf of Mexico. Elasmopus yucalpeten sp. n. is recognized from its congeners by a two-articulate accessory flagellum, a group of long robust setae on the anterodistal margin of the gnathopod 2 basis, a distomedial concave portion on palm of gnathopod 2 propodus, long setae on basis posterior margin of pereopods 5–7, and an entire telson. The differences among closely related species are pointed out and they are compared with the new species. An identification key to species of the genus Elasmopus in the Gulf of Mexico and biogeographic comments at the regional and global scales are also provided.

  4. Spatial and temporal characterization of fish assemblages in a tropical coastal system influenced by freshwater inputs: northwestern Yucatan peninsula

    Directory of Open Access Journals (Sweden)

    Daniel Arceo-Carranza

    2009-06-01

    Full Text Available Coastal lagoons are important systems for freshwater, estuarine and marine organisms; they are considered important zones of reproduction, nursery and feeding for many fish species. The present study investigates the fish assemblages of the natural reserve of Dzilam and their relationship with the hydrologic variables. A total of 6 474 individuals (81 species were collected, contributing with more than 50% considering the Importance Value Index (IVI, Sphoeroides testudineus, Fundulus persimilis, Anchoa mitchilli, Eucinostomus gula, Eucinostomus argenteus and Mugil trichodon. Differences in species composition were found between seasons the highest during the cold fronts. Spatially, differences were related with the presence of freshwater seeps, the highest in the ecological characterized eastern part and the lowest with higher difference in specific composition located in the western part of the internal zone, due to a higher abundance and dominance of L. rhomboides. Salinity and temperature were the variables that presented a higher influence in the distribution of some pelagic species such as A. mitchilli and A. hepsetus. Because of the abundant freshwater seeps characteristic of the coastal lagoons of Yucatan Peninsula their community structure and fish assemblage display spatial and temporal differences in specific composition. Rev. Biol. Trop. 57 (1-2: 89-103. Epub 2009 June 30.Las lagunas costeras son sistemas importantes para muchas especies de organismos dulceacuícolas, estuarinos y marinos, ya que son consideradas zonas de reproducción, refugio y alimentación de muchas especies de peces. El presente estudio analizó los ensamblajes de la comunidad íctica de la reserva de Dzilam y su relación con las variables hidrológicas. Se capturaron un total de 6 474 individuos (81 especies, en donde Sphoeroides testudineus, Fundulus persimilis, Anchoa mitchilli, Eucinostomus gula, Eucinostomus argenteus and Mugil trichodon contribuyeron con m

  5. Apicultura y organizaciones de apicultores entre los mayas de Yucatán Beekeeping and Apicultural Organizations Among the Mayas of Yucatan

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    Margarita Rosales González

    2010-01-01

    Full Text Available En las comunidades mayas la apicultura continúa siendo una actividad relevante pero complementaria, cuya lógica y condiciones de producción se contraponen a las nuevas normas del mercado internacional. La integración de organizaciones apícolas se considera una estrategia para la "modernización" de la apicultura y la comercialización de la miel en mejores condiciones. Este trabajo se refiere al sentido que tanto la apicultura como estas organizaciones tienen para sus integrantes, a sus expectativas, intereses, aprendizajes y a la forma en que se relacionan con instituciones y agentes externos. El escrito se basa en entrevistas y observaciones realizadas en 12 organizaciones apícolas durante 2005 y 2006 en el marco del proyecto de investigación del centro INAH Yucatán "Organizaciones indígenas y procesos de desarrollo en comunidades mayas del sur de Yucatán".In Mayan communities, beekeeping continues to be an important but complementary activity, whose logic and conditions of production are opposed to the new norms of the international market. The integration of apicultural organizations is considered as a strategy for the "modernization" of beekeeping and the commercialization of the honey in better quality. The present research deals with the meaning that beekeeping has for the members of such organizations, and it explores the expectations, interests and training processes of the members, analyzing finally how are the relationships between these organizations and external agents and institutions. The research is based on interviews and observations made in 12 apicultural organizations between 2005 and 2006, as part of the research project of the INAH Regional Center Yucatan, entitled "Indigenous Organizations and Processes of Development in Mayan Communities in Southern Yucatan".

  6. Cumplimiento de las promesas en el marco de la calidad del servicio de alojamiento turístico del estado Mérida, Venezuela. Compliance with the promises related to the quality of the Merida state tourist accommodation service, Venezuela.

    OpenAIRE

    Díaz Pérez, Flora María; Morillo Moreno, Marysela Coromoto

    2017-01-01

    ResumenLa actividad turística, pese a esfuerzos realizados, no es actualmente un sector relevante en Venezuela, sin embargo, constituye una alternativa para el desarrollo económico. El estudio de la competitividad del sector turístico venezolano es pertinente, donde la calidad y los servicios de alojamiento son componentes fundamentales. En este trabajo se determinó si se da el cumplimiento de las promesas sobre el servicio por parte de los proveedores de alojamiento turístico del estado Méri...

  7. Measuring the Wavelength of a Diode Laser and the Birefringence of Mica: The Experimental Examination of the IPHO 40 Held in Mexico

    Science.gov (United States)

    Moran-Lopez, J. L.; Ortiz, M. E.; Rodriguez, L. F.; Romero-Rochin, V.

    2010-01-01

    The experimental examination applied in the 40th International Physics Olympiad held in Merida, Yucatan, Mexico, is presented. The examination consisted of two parts: (1) based on the measurements of a diffraction pattern produced by a diode laser impinging on a sharp edge of a razor blade, the students were asked to estimate the wavelength of the…

  8. Design and validation of a scale to identify stereotypes against indigenous people

    Directory of Open Access Journals (Sweden)

    Rebelín Echeverría Echeverría

    2013-12-01

    Full Text Available The aim of this study was to design and validate a scale to identify prejudices against indigenous people as a socially stigmatised and culturally relevant group in Mexican samples, and establishing gender differences in undergraduate students. A sample of 563 undergraduate students was drawn from Merida, the capital city, and inner towns in the state of Yucatan, Mexico. From the sample, 272 were women and 292 were men with an average age of 23.06 years. To measure beliefs scale was developed consisted of 50 Likert reagents to assess stereotypical beliefs toward indigenous people. Factor analysis threw five main factors. Results show that the scale has adequate psychometric qualities, including reliability and validity.

  9. First Detection of the Kdr Mutation T929I in Head Lice (Phthiraptera: Pediculidae) in Schoolchildren of the Metropolitan Area of Nuevo Leon and Yucatan, Mexico.

    Science.gov (United States)

    Ponce-Garcia, Gustavo; Villanueva-Segura, Karina; Trujillo-Rodriguez, Gerardo; Rodriguez-Sanchez, Iram P; Lopez-Monroy, Beatriz; Flores, Adriana E

    2017-07-01

    The head louse Pediculus humanus capitis (De Geer) is a hematophagous ectoparasite that inhabits the human scalp. Infestations by this insect are commonly known as pediculosis, which is more common in younger groups. These infestations are asymptomatic; however, skin irritation from scratching occasionally may cause secondary bacterial infections. In recent years, the prevalence of pediculosis has increased in children; this increase has been attributed to louse resistance to the insecticides used as a control measure for infestation. The aim of the present study was to determine the presence and frequency of the knockdown resistance mutation (kdr) T929I in 468 head lice collected from 32 elementary schools in the metropolitan area of Nuevo Leon (24) and Yucatan (8), Mexico. This is the first report of a knockdown resistance (kdr) mechanism in head lice from Mexico. The T929I mutation was present in all of the sampled schools, with variability observed in its allelic and genotypic frequencies. © The Authors 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Detection of antibodies and risk factors for infection with bovine respiratory syncytial virus and parainfluenza virus-3 in beef cattle of Yucatan, Mexico.

    Science.gov (United States)

    Solís-Calderón, J J; Segura-Correa, J C; Aguilar-Romero, F; Segura-Correa, V M

    2007-11-15

    We collected blood samples from 756 > or =2-year-old cattle in 54 herds in Yucatan, Mexico, and used all of those to determine the antibody seroprevalences (in an indirect enzyme-linked inmunosorbance assay) to bovine respiratory syncytial virus (BRSV) and risk factors for animal-level seropositivity. We used 728 of the same samples (from 52 of the same herds) to do the same for parainfluenza virus-3 (PIV3). Cattle were selected by two-stage cluster sampling. Herd-level and animal-level risk factors were obtained through a personal interview. We analyzed the data by using a random-effects multivariable logistic regression model for clustered observations. All herds had at least 3 (BRSV) or 5 (PIV3) seropositive animals. The animal-level true seroprevalences were: 90.8% (86.5, 95.2%) and 85.6% (80.9, 90.4%) for BRSV and PIV3, respectively. Animals in large herds and old animals had the highest odds of being seropositives to BRSV, and those risk factors plus animals born on the farm for PIV3 infection.

  11. Characterization of constitutive materials and technology of the mural painting of the acropolis of the archaeological zone of Ek Balam, Yucatan, Mexico

    International Nuclear Information System (INIS)

    Alonso O, A.; Vazquez N, J.; Ruiz M, C.; Mendoza A, D.; Espinosa P, M.; Ruvalcaba, J.L.; Vandenabeele, P.

    2005-01-01

    The conservation project of Ek'Balam is one of the few experiences of systematic conservation applied in an archaeological Maya site at the Yucatan Peninsula in Mexico. The project started in the year 2001 when important stone, stucco and painting decorations were discovered during archaeological excavations. Being a recently discovered site, the conservation program includes a research program based on particular conservation issues detected as potential risk of archaeological data losses. One of the research topics is based on deter- mining the ancient painting technology used in mural and stucco decorations through the characterization of building and decorative composite materials. Archaeometric techniques have been used to fulfil the proposed goal. Raman, X-ray Fluorescence, Light and Electron Microscopy were practiced on a set of 35 wall painting samples. Preliminary results obtained on pigments characterization have partially revealed general features of wall painting technique at Ek'Balam during the late Classic period. Some particular pigments, not reported ever for mural paintings, have been identified in Ek'Balam samples. (Author)

  12. Begomovirus diversity in tomato crops and weeds in Ecuador and the detection of a recombinant isolate of rhynchosia golden mosaic Yucatan virus infecting tomato.

    Science.gov (United States)

    Paz-Carrasco, Lenin C; Castillo-Urquiza, Gloria P; Lima, Alison T M; Xavier, Cesar A D; Vivas-Vivas, Leticia M; Mizubuti, Eduardo S G; Zerbini, F Murilo

    2014-08-01

    Viral diseases caused by begomoviruses are of economic importance due to their adverse effects on the production of tropical and subtropical crops. In Ecuador, despite reports of significant infestations of Bemisia tabaci in the late 1990s, only very recently has a begomovirus, tomato leaf deformation virus (ToLDeV, also present in Peru), been reported in tomato. ToLDeV is the first monopartite begomovirus discovered that originated in the Americas, and its presence in Ecuador highlights the need for a wider survey of tomato-infecting begomoviruses in this country. Tomato and weed samples were collected in 2010 and 2011 in six provinces of Ecuador, and begomovirus genomes were cloned and sequenced using a rolling-circle-amplification-based approach. Most tomato samples from the provinces of Guayas, Loja, Manabi and Santa Elena were infected with tomato leaf deformation virus (ToLDeV). One sample from Manabi had a triple infection with ToLDeV, rhynchosia golden mosaic Yucatan virus (RhGMYuV) and an isolate that was a recombinant between the two. A new begomovirus was detected in another tomato sample from Manabi. Samples of Rhynchosia sp. from the provinces of Guayas and Manabi were infected by RhGMYuV. These results indicate not only the prevalence of ToLDeV in tomato in Ecuador but also the presence of other viruses, albeit at a much lower frequency.

  13. A method for the stochastic modeling of karstic systems accounting for geophysical data: an example of application in the region of Tulum, Yucatan Peninsula (Mexico)

    Science.gov (United States)

    Vuilleumier, C.; Borghi, A.; Renard, P.; Ottowitz, D.; Schiller, A.; Supper, R.; Cornaton, F.

    2013-05-01

    The eastern coast of the Yucatan Peninsula, Mexico, contains one of the most developed karst systems in the world. This natural wonder is undergoing increasing pollution threat due to rapid economic development in the region of Tulum, together with a lack of wastewater treatment facilities. A preliminary numerical model has been developed to assess the vulnerability of the resource. Maps of explored caves have been completed using data from two airborne geophysical campaigns. These electromagnetic measurements allow for the mapping of unexplored karstic conduits. The completion of the network map is achieved through a stochastic pseudo-genetic karst simulator, previously developed but adapted as part of this study to account for the geophysical data. Together with the cave mapping by speleologists, the simulated networks are integrated into the finite-element flow-model mesh as pipe networks where turbulent flow is modeled. The calibration of the karstic network parameters (density, radius of the conduits) is conducted through a comparison with measured piezometric levels. Although the proposed model shows great uncertainty, it reproduces realistically the heterogeneous flow of the aquifer. Simulated velocities in conduits are greater than 1 cm s-1, suggesting that the reinjection of Tulum wastewater constitutes a pollution risk for the nearby ecosystems.

  14. Bupivacaine mandibular nerve block affects intraoperative blood pressure and heart rate in a Yucatan miniature swine mandibular condylectomy model: a pilot study.

    Science.gov (United States)

    Bova, Jonathan F; da Cunha, Anderson F; Stout, Rhett W; Bhumiratana, Sarindr; Alfi, David M; Eisig, Sidney B; Vunjak-Novakovic, Gordana; Lopez, Mandi J

    2015-02-01

    The primary objective was to evaluate the effect of a bupivacaine mandibular nerve block on intraoperative blood pressure (BP) and heart rate (HR) in response to surgical stimulation and the need for systemic analgesics postoperatively. We hypothesized that a mandibular nerve block would decrease the need for systemic analgesics both intraoperatively and postoperatively. Fourteen adult male Yucatan pigs were purchased. Pigs were chemically restrained with ketamine, midazolam, and dexmedetomidine and anesthesia was maintained with isoflurane inhalant anesthesia. Pigs were randomized to receive a mandibular block with either bupivacaine (bupivacaine group) or saline (control group). A nerve stimulator was used for administration of the block with observation of masseter muscle twitch to indicate the injection site. Invasive BP and HR were measured with the aid of an arterial catheter in eight pigs. A rescue analgesic protocol consisting of fentanyl and lidocaine was administered if HR or BP values increased 20% from baseline. Postoperative pain was quantified with a customized ethogram. HR and BP were evaluated at base line, pre-rescue, 10 and 20 min post-rescue. Pre-rescue mean BP was significantly increased (p = .001) for the bupivacaine group. Mean intraoperative HR was significantly lower (p = .044) in the bupivacaine versus saline group. All other parameters were not significant. Addition of a mandibular nerve block to the anesthetic regimen in the miniature pig condylectomy model may improve variations in intraoperative BP and HR. This study establishes the foundation for future studies with larger animal numbers to confirm these preliminary findings.

  15. Effects of Trichoderma harzianum Rifai over Plasmodiophora brassicae Woronin in broccoli, in Escagüey, municipality of Rangel, Mérida State

    Directory of Open Access Journals (Sweden)

    Mirna Labrador Morales

    2016-03-01

    Full Text Available The effectiveness of Trichoderma harzianum in suppressing clubroot of brassicas, which is caused by Plasmodiophora brassicae, was tested on broccoli (Brassica oleracea var. italica Plenck, in field conditions, in Escagüey, municipality of Rangel, Merida State, Venezuela. The experiment showed that the applications of a biopesticide based on this antagonist had a significant effect on the percentage of health plants and the crop yields, in dependence of the dose used. In addition, the relation benefits/cost was also favorable. These results showed that, for these particular conditions, P. brassicae is an adequate biological alternative to control the clubroot of brassicas, no aggressive to environment and human beings, useful for the transition phase toward a sustainable agriculture, without chemical pesticides.

  16. Effects of Trichoderma harzianum Rifai over Plasmodiophora brassicae Woronin in broccoli, in Escagüey, municipality of Rangel, Mérida state

    Directory of Open Access Journals (Sweden)

    Mirna Labrador Morales

    2014-04-01

    Full Text Available The effectiveness of Trichoderma harzianum in suppressing clubroot of brassicas, which is caused by Plasmodiophora brassicae, was tested on broccoli (Brassica oleracea var. italica Plenck, in field conditions, in Escagüey, municipality of Rangel, Merida State, Venezuela. The experiment showed that the applications of a biopesticide based on this antagonist had a significant effect on the percentage of health plants and the crop yields, in dependence of the dose used. In addition, the relation benefits/cost was also favorable. These results showed that, for these particular conditions, P. brassicae is an adequate biological alternative to control the clubroot of brassicas, no aggressive to environment and human beings, useful for the transition phase toward a sustainable agriculture, without chemical pesticides.

  17. Reconstruction of precipitation variability in the Strait of Yucatan associated with latitudinal shifts in the position of the Intertropical Convergence Zone since the Last Glacial Maximum

    Science.gov (United States)

    Staines-Urías, Francisca; Seidenkrantz, Marit-Solveig; Fischel, Andrea; Kuijpers, Antoon

    2017-04-01

    The elemental composition of sediments from gravity core HOLOVAR11-03 provides a ca. 40 ka record of past climate variability in the Strait of Yucatan, between the Caribbean Sea and the Gulf of Mexico, a region where precipitation variability is determined by the seasonal position of the Intertropical Convergence Zone (ITCZ). Within this region, sea level pressure decreases and rainfall increases as the ITCZ moves north of the equator in response to increased solar insolation in the Northern Hemisphere during boreal summer. In contrast, as the ITCZ retracts southward towards the equator during boreal winter, rainfall diminishes and the regional sea level pressure gradient strengthens. On interannual, multidecadal and millennial timescales, fluctuations in the average latitudinal position of the ITCZ in response to insolation forcing modulate the intensity and duration of the seasonal regimens, determining average regional precipitation and, ultimately, the elemental composition of the marine sedimentary record. Regionally, higher titanium and iron content in marine sediments reflect greater terrigenous input from inland runoff, indicating greater precipitation, hence a more northerly position of the ITCZ. Correspondingly, Ti and Fe concentration data were used to reconstruct regional rainfall variability since the Last Glacial Maxima (LGM ˜24 cal ka BP). HOLOVAR11-03 age model (based on 4 AMS 14C dates obtained from multi-specific samples of planktic foraminifera) shows stable sedimentation rates in the area throughout the cored period. Nonetheless, higher terrestrial mineral input is observed since the LGM and all through the last glacial termination (24 to 12 cal ka BP), indicating a period of increased precipitation. In contrast, lower Ti and Fe values are typical for the period between 12 and 8 cal ka BP, indicating reduced precipitation. A positive trend characterizes the following interval, showing a return to wetter conditions lasting until 5 cal ka BP

  18. Palaeoenvironmental Evolution of Cenote Aktun Ha (Carwash) on the Yucatan Peninsula, Mexico and its Response to Holocene Sea-Level Rise

    Science.gov (United States)

    Gabriel, J. J.; Reinhardt, E. G.; Peros, M. C.; Davidson, D. E.; van Hengstum, P. J.; Beddows, P. A.

    2008-12-01

    A 61-cm core was obtained from 4 metres below the water table in Cenote Aktun Ha, on the Yucatan Peninsula, Mexico. The cenote is 8.6 km from the Caribbean coast and its formation and evolution have been largely affected by sea-level change. The base of the core dates to 6940 - 6740 cal yr BP and overlying sediments were deposited rapidly over the subsequent ~200 years. The pollen record shows that the cenote evolved from a marsh dominated by red mangrove (Rhizophora mangle) and fern (Polypodiaceae) to an open-water system. These vegetation changes were controlled by water level and salinity and are thus useful indicators of past sea level. At the base, the d13C isotopic ratios reveal the influence of terrestrial vegetation (-29‰), but shift to more negative values up-core (-33‰), indicating an influence from particulate matter in the flooded cenote pool. Although microfossil populations were nearly absent through most of the core, the microfossil assemblage in the upper 6 cm of the core is dominated by juvenile Ammonia tepida and the thecamoebian genus Centropyxis. These populations indicate open-water conditions in the cenote and a major environmental shift around 6600 cal yr BP, which is related to sea-level rise in the Caribbean basin. These data fit well with previously established sea-level curves for the Caribbean Sea. Our reconstruction of the environmental history of Cenote Aktun Ha helps elucidate the floral and hydrological history of the region, and highlights the utility of cenote sediments for studying the Holocene sea-level history of the Caribbean Sea.

  19. Yucatan Subsurface Stratigraphy from Geophysical Data, Well Logs and Core Analyses in the Chicxulub Impact Crater and Implications for Target Heterogeneities

    Science.gov (United States)

    Canales, I.; Fucugauchi, J. U.; Perez-Cruz, L. L.; Camargo, A. Z.; Perez-Cruz, G.

    2011-12-01

    Asymmetries in the geophysical signature of Chicxulub crater are being evaluated to investigate on effects of impact angle and trajectory and pre-existing target structural controls for final crater form. Early studies interpreted asymmetries in the gravity anomaly in the offshore sector to propose oblique either northwest- and northeast-directed trajectories. An oblique impact was correlated to the global ejecta distribution and enhanced environmental disturbance. In contrast, recent studies using marine seismic data and computer modeling have shown that crater asymmetries correlate with pre-existing undulations of the Cretaceous continental shelf, suggesting a structural control of target heterogeneities. Documentation of Yucatan subsurface stratigraphy has been limited by lack of outcrops of pre-Paleogene rocks. The extensive cover of platform carbonate rocks has not been affected by faulting or deformation and with no rivers cutting the carbonates, information comes mainly from the drilling programs and geophysical surveys. Here we revisit the subsurface stratigraphy in the crater area from the well log data and cores retrieved in the drilling projects and marine seismic reflection profiles. Other source of information being exploited comes from the impact breccias, which contain a sampling of disrupted target sequences, including crystalline basement and Mesozoic sediments. We analyze gravity and seismic data from the various exploration surveys, including multiple Pemex profiles in the platform and the Chicxulub experiments. Analyses of well log data and seismic profiles identify contacts for Lower Cretaceous, Cretaceous/Jurassic and K/Pg boundaries. Results show that the Cretaceous continental shelf was shallower on the south and southwest than on the east, with emerged areas in Quintana Roo and Belize. Mesozoic and upper Paleozoic sediments show variable thickness, possibly reflecting the crystalline basement regional structure. Paleozoic and Precambrian

  20. On the phylogenetic position of Pseudophilomedinae within Sarsielloidea (Ostracoda, Myodocopida), with a description of one new Harbansus from Ningaloo Reef and redescription of H. paucichelatus from Yucatan

    Science.gov (United States)

    Karanovic, Ivana; Orduña-Martínez, Lorena; Ardisson, Pedro-Luis

    2015-03-01

    Previous studies have suggested incongruence between current systematics and molecular phylogenies of Sarsielloidea, with a possible polyphyly of the family Philomedidae. Here, we provide molecular phylogenetic analyses based on 18S rDNA and 28S rDNA. The former includes five new sequences and 12 from the GenBank, and the latter two new and six sequences from the GenBank. We use three methods, maximum likelihood, maximum parsimony, and neighbor joining, and all reconstructed phylogenies support previously suggested polyphyly, indicating a closer relationship of the subfamily Pseudophilomedinae with one subfamily of Sarsiellidae than with the nominotypical subfamily of Philomedidae. Morphological characters that may be key indicators of the phylogenetic relationships between three Sarsielloidea families are discussed. We also describe the 21st representative of the Pseudophilomedinae genus, Harbansus Kornicker, (Smith Contrib Zool 260:75, 1978), Harbansus ningalooi n. sp., from the Ningaloo Reef, Western Australia. This is the first Harbansus reported from the Australian west coast and the second from the Australian coral reef systems. It differs from all other congeners by peculiar claw-like processes on the posterior infold. Most Harbansus species have relatively restricted distributions, except Harbansus paucichelatus (Kornicker, in Inst Mar Sci 5:195-300, 1958), which has also been postulated to represent a species complex. We present a detailed morphological redescription of this species, based on the freshly collected material from the Yucatan Peninsula, as well as four mitochondrial COI sequences. These become the first COI sequences of the entire superfamily Sarsielloidea available on the GenBank. To facilitate future identification, we include a key to species of Harbansus.

  1. PRESENCE OF PESTICIDES IN THE KARSTIC AQUIFER BETWEEN THE MUNICIPALITIES OF MÉRIDA TO PROGRESO, YUCATÁN, MÉXICO

    Directory of Open Access Journals (Sweden)

    Germán Giácoman Vallejos

    2017-07-01

    Full Text Available Pollution by pesticides has become relevant worldwide due to its serious effects on living organisms. Pesticides act as endocrine disrupters, affect the immune system, decrease the reproductive capacity and some are potentially carcinogenic for human beings. For the characteristicsmentioned, their high environmental persistence and bioacumulation potential in fat tissues,since 1970, some of the organochlorade pesticides have been restricted in many countries, and it is necessary their monitoring. In the Yucatan State, the predominant karstic nature of soil enables the infiltration of a wide range of substances to the underground hydric resources, polluting them. Particularly, it can be observed the north occidental state region, which is characterized by the presence of human settlements, agricultural activity and ground water flows oriented towards the north coast. The present study presents the results of a research carried outin the north occidental region of the Yucatan State (between the municipalities of Merida and Progreso about the groundwater pollution by the presence of4,4´-DDT, 4,4´-DDD, 4,4´-DDE, lindane, endosulphan I and endosulphansulfate. The DDT concentrations and its derivatives as well as the endosulphan found in the area represent a risk for human water consumption, according to the mexican regulatory NOM-127-SSA1-1994.

  2. Characterization of constitutive materials and technology of the mural painting of the acropolis of the archaeological zone of Ek Balam, Yucatan, Mexico; Caracterizacion de materiales constitutivos y tecnologia de la pintura mural de la acropolis de la zona arquelogica de Ek Balam, Yucatan, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Alonso O, A.; Vazquez N, J.; Ruiz M, C. [INAH, 11000 Mexico D.F. (Mexico); Mendoza A, D.; Espinosa P, M. [ININ, 52045 Ocoyoacac, Estado de Mexico (Mexico); Ruvalcaba, J.L. [IFUNAM, 04510 Mexico D.F. (Mexico); Vandenabeele, P. [Universidad de Ghent, Belgica (Belgium)]. e-mail: alealonsolvera@yahoo.com

    2005-07-01

    The conservation project of Ek'Balam is one of the few experiences of systematic conservation applied in an archaeological Maya site at the Yucatan Peninsula in Mexico. The project started in the year 2001 when important stone, stucco and painting decorations were discovered during archaeological excavations. Being a recently discovered site, the conservation program includes a research program based on particular conservation issues detected as potential risk of archaeological data losses. One of the research topics is based on deter- mining the ancient painting technology used in mural and stucco decorations through the characterization of building and decorative composite materials. Archaeometric techniques have been used to fulfil the proposed goal. Raman, X-ray Fluorescence, Light and Electron Microscopy were practiced on a set of 35 wall painting samples. Preliminary results obtained on pigments characterization have partially revealed general features of wall painting technique at Ek'Balam during the late Classic period. Some particular pigments, not reported ever for mural paintings, have been identified in Ek'Balam samples. (Author)

  3. Interannual variability in the extent and intensity of tropical dry forest deciduousness in the Mexican Yucatan (2000-2016): Drivers and Links to Regional Atmospheric Conditions

    Science.gov (United States)

    Cuba, Nicholas Joseph

    The dry topical forests of the southern Yucatan Peninsula experience multiple natural and anthropogenic disturbances, as well as substantial interannual climate variability that can result in stark interannual differences in vegetation phenology. Dry season deciduousness is a typical response to limit tree water loss during prolonged periods of hot and dry conditions, and this behavior has both direct implications for ecosystem functioning, and the potential to indicate climate conditions when observed using remotely-sensed data. The first research paper of this dissertation advances methods to assess the accuracy of remotely-sensed measurements of canopy conditions using in-situ observations. Linear regression models show the highest correlation (R2 = 0.751) between in-situ canopy gap fraction and Landsat NDWISWIR2. MODIS time series NDWISWIR2 are created for the period March 2000-February 2011, and exhibit stronger correlation with time series of TRMM precipitation data than do MODIS EVI time series (R2= 0.48 vs. R2 = 0.43 in deciduous forest areas). The second paper examines differences between the deciduous phenology of young forest stands and older forest stands. Land-cover maps are overlaid to determine whether forested areas are greater than or less than 22 years old in 2010, and metrics related to deciduous phenology are derived from MODIS EVI2 time series in three years, 2008 to 2011. Statistical tests that compare matched pairs of young (12-22 years) and older (>22 years) forest stand age class samples are used to detect significant differences in metrics related to the intensity and timing of deciduousness. In all three years, younger forests exhibit significantly more intense deciduousness, measured as total seasonal change of EVI2 normalized by annual maximum EVI2 (paccounted for in part by the comparatively low amount of early dry-season rainfall during these years, increasing the rate of desiccation of fuel load, and may arise from the large

  4. New records of caridean shrimps (Decapoda: Caridea from shallow water along the northern Yucatan peninsula coasts of México

    Directory of Open Access Journals (Sweden)

    Luis Daniel Santana-Moreno

    Full Text Available The northern coast of the Mexican state of Yucatán has only been cursorily sampled in the past, with most of this effort concentrated on the largest coral reef in the Gulf of México, Arrecife Alacranes. The present study reports on recent collections (June 2008 - September 2013 of caridean shrimp in Yucatán, including Arrecife Alacranes and other reefs, as well as coastal lagoons and beaches. Additionally, a number of species are reported based on older, unidentified museum material. Six species represent new records for the Gulf of México [Janicea antiguensis (Chace, 1972, Gnathophyllum modestum Hay, 1917, Lysmata jundalini Rhyne, Calado and dos Santos, 2012, Periclimenes sandyi De Grave, 2009, Rapipontonia platalea (Holthuis, 1951a, Typton tortugae, McClendon, 1911], and 11 species are confirmed new records for México [Lysmata ankeri Rhyne and Lin, 2006, L. pederseni Rhyne and Lin, 2006, L. rafa Rhyne and Anker, 2007, Ascidonia miserabilis (Holthuis, 1951b, A. quasipusilla (Chace, 1972, Neopontonides chacei Heard, 1986, Periclimenaeus maxillulidens (Schmitt, 1936, P. pearsei (Schmitt, 1932, P. schmitti Holthuis, 1951b, Typton prionurus Holthuis, 1951b, Processa manningi De Grave and Felder, 2012], adding up to a total of 17 newly reported species for the East coast of México. Further, the colour pattern of several species is documented for the first time.

  5. Assessment of intravenous pbi-shRNA PDX1 nanoparticle (OFHIRNA-PDX1) in yucatan swine.

    Science.gov (United States)

    Jay, C M; Ruoff, C; Kumar, P; Maass, H; Spanhel, B; Miller, M; Arrington, A; Montalvo, N; Gresham, V; Rao, D D; Evans, C; Wang, Z; Brunicardi, F C; Liu, S-H; Zhou, G; Senzer, N; Nemunaitis, J; King, L; Weeks, B; Clubb, F J; Fossum, T W; Maples, P B

    2013-12-01

    PDX1 (pancreatic and duodenal homeobox 1) is overexpressed in pancreatic cancer, and its reduction results in tumor regression. Bi-functional pbi-shRNA PDX1 nanoparticle (OFHIRNA-PDX1) utilizes the endogenous micro-RNA biogenesis pathway to effect cleavage- and non-cleavage-dependent degradation of PDX1 mRNA. We have shown that OFHIRNA-PDX1 reduces pancreatic tumor volume in xenograft models. Thus, we are now exploring biorelevant large animal safety of OFHIRNA-PDX1. Mini pigs were chosen as the biorelevant species based on the similarity of human and pig PDX1 target sequence. In the initial study, animals developed fever, lethargy, hyporexia and cutaneous hyperemia following administration of OFHIRNA-PDX1. Twenty-one days later, the same animals demonstrated less toxicity with a second OFHIRNA-PDX1 infusion in conjunction with a prophylactic regimen involving dexamethasone, diphenhydramine, Indocin and ranitidine. In a new group of animals, PDX1 protein (31 kDa) expression in the pancreas was significantly repressed at 48 and 72 h (85%, P=0.018 and 88%, P=0.013; respectively) following a single infusion of OFHIRNA-PDX1 but recovered to normal state within 7 days. In conclusion, a single intravenous infusion of OFHIRNA-PDX1 in conjunction with premedication in pigs was well tolerated and demonstrated significant PDX1 knockdown.

  6. [Anatomy and uses of the mature leaves of three species of Sabal (Arecaceae) of the Yucatan, México].

    Science.gov (United States)

    Pérez, Martha; Rebollar, Silvia

    2003-06-01

    This paper describes the leaf anatomy of Sabal mauritiiformis (Karst.) Griseb. & H. Wendl., Sabal mexicana Mart. and Sabal yapa Wright ex Becc., three of the four most representative species of the Yucatán Península, in Mexico. These species are locally used: in the roofing of traditional homes, as food (fruits and apical buds), and in the production of hats, brooms and handicrafts. Leaf samples were collected in secondary growth of lower montane rainforest in the state of Quintana Roo and in two home gardens in the state of Yucatán. Herbarium samples were obtained, and samples of blade and petiole were fixed in formaline-acetic acid-alcohol. Cross incisions were made on the blade and petiole, and were dyed with safranin and toluidine blue O. The results show that S. mauritiiformis and S. yapa are morphologically alike: both are tall, slim palm trees; the leaf in S. mauritiiformis is a shorter palm-like structure compared with the other two species. The shape of the main nerve, as seen in cross section, is rectangular in the three species. The hastula in the three species is acuminate and adaxial. The foliar anatomic structure is similar in the three species, although there are some differences. The adaxial an abaxial epidermis of the blade consist of one layer and, superficially, the anticlinal walls are straight; the stomata are intercostal, of the tetracytic type, present on both surfaces in S. mexicana and S. yapa and only on the abaxial surface on S. mauritiiformis. The hypodermis is one layer thick in S. yapa and in S. mexicana and two layers thick in S. mauritiiformis. In the three species the palisade parenchyma consists of several undefined strata as the cells are similar-in shape and size--to the cells in the spongy parenchyma, so there is no marked difference between these strata and the spongy parenchyma seems almost continuous. Both fibrous and vascular bundles are distributed between the hypodermis and the palisade parenchyma; the fiber bundles can

  7. ( Didelphis virginiana ) from Yucatan, Mexico

    African Journals Online (AJOL)

    Toxoplasma gondii is an obligate intracellular parasite recognized as a causal agent of toxoplasmosis; zoonotic disease endemic in many countries worldwide, including Mexico. Different species of animals participate in the wild cycle infection, including opossums of the species Didelphis virginiana. Thirteen D. virginiana ...

  8. El cuidado de enfermería en pacientes con ventilación mecánica asistida

    OpenAIRE

    Vega Morales, Elsy Guadalupe

    2013-01-01

    This qualitative study had as objectives to describe and analyze the styles of care / caring performed by nurses on the adult patient with mechanical ventilation. Maturana, Figueiredo and Boff were the authors who gave support to the theoretical and philosophical study. A total of ten nurses at the intensive care unit of Dr. Augustine O’Horán General Hospital in Merida, Yucatan, Mexico, participated in the study. Data were obtained through profound interviews and participant observation. The ...

  9. Merida Initiative: Insight Into U.S. Mexico Relations

    Science.gov (United States)

    2016-09-01

    accomplishment. I would like to thank my parents for their love and support in all of life’s endeavors and encouraging me to pursue a military...accessed May 7, 2016, https://www.stratfor.com/sites/default/files/ styles /stratforfull/public/main/images/ mexico_cartels_v7_1.jpg?itok=oPd1GY7E. 31...countries like Pakistan , Afghanistan, 128 Ibid., 171–172. 129 Liana Sun Wyler, Weak and Failing

  10. De miasmas a mosquitos: el pensamiento médico sobre la fiebre amarilla en Yucatán, 1890-1920 From miasmas to mosquitoes: medical thought on yellow fever in Yucatan, 1890-1920

    Directory of Open Access Journals (Sweden)

    Carlos Alcalá Ferráez

    2012-03-01

    Full Text Available La fiebre amarilla fue un problema de salud pública desde la época colonial debido a la frecuencia con que se presentaba en forma epidémica y a su alta letalidad. El objetivo de este trabajo es analizar el pensamiento médico y su evolución con respecto al vómito prieto entre 1890 y 1921 en Yucatán. Dos aspectos serán abordados: algunos antecedentes con respecto a la enfermedad y las ideas predominantes hasta 1881; y la propuesta de Carlos Finlay para vencer el escepticismo ante su teoría por parte de la comunidad médica. En segundo lugar se analizará la mezcla de las ideas miasmáticas y bacterianas. En tercer lugar, se mostrará cómo, a partir de la demostración de sus postulados, la mirada médica se dirigió al exterminio del mosquito transmisor de este padecimiento.Yellow fever has been a public health concern since colonial days because of its frequent epidemics and high mortality rate. This analysis of medical thought about "the black vomit" in the Yucatan and the evolution of this thinking from 1890 through 1921 first addresses some of the disease's antecedents and preponderant ideas prior to 1881 as well as Carlos Finlay's efforts to convince the medical community that his theory was right. The article goes on to analyze the co-existence of miasmatic and bacterial ideas and to show how medical initiatives began focusing on eradication of the mosquito transmitter once Finlay's postulates had been demonstrated.

  11. Comparison of small mammal prevalence of Leishmania (Leishmania) mexicana in five foci of cutaneous leishmaniasis in the State of Campeche, Mexico.

    Science.gov (United States)

    Van Wynsberghe, N R; Canto-Lara, S B; Sosa-Bibiano, E I; Rivero-Cárdenas, N A; Andrade-Narváez, F J

    2009-01-01

    In the Yucatan Peninsula of Mexico, 95% of the human cases of Cutaneous Leishmaniasis are caused by Leishmania (Leishmania) mexicana with an incidence rate of 5.08 per 100,000 inhabitants. Transmission is limited to the winter months (November to March). One study on wild rodents has incriminated Ototylomys phyllotis and Peromyscus yucatanicus as primary reservoirs of L. (L.) mexicana in the focus of La Libertad, Campeche. In the present study, the prevalence of both infection and disease caused by L. (L.) mexicana in small terrestrial mammals were documented during five transmission seasons (1994-2004) in five foci of Leishmaniasis in the state of Campeche. Foci separated by only 100 km, with similar relative abundances of small mammals, were found to differ significantly in their prevalence of both symptoms and infection. Transmission rates and reservoir species seemed to change in space as well as in time which limited the implementation of effective control measures of the disease even in a small endemic area such as the south of the Yucatan Peninsula.

  12. Susceptibilidad y mecanismos de resistencia a insecticidas en Anopheles albimanus del sur de la Península de Yucatán, México Susceptibility and inseticide resistance mechanisms in Anopheles albimanus from the southern Yucatan Peninsula, Mexico

    Directory of Open Access Journals (Sweden)

    Felipe A. Dzul

    2007-08-01

    Full Text Available OBJETIVOS: Diagnosticar la resistencia a insecticidas y sus mecanismos en Anopheles albimanus del sur de la Península de Yucatán (PY, México. MATERIAL Y MÉTODOS: La F1 de An. albimanus colectados durante noviembre-diciembre de 2005 en seis localidades de los municipios Othón P. Blanco en Quintana Roo y Calakmul en Campeche, fue sometida a pruebas de susceptibilidad con deltametrina, DDT, pirimifos metil y bendiocarb, y a pruebas bioquímicas para calcular los niveles de las enzimas involucradas en la resistencia. RESULTADOS: An. albimanus fue resistente al DDT y a deltametrina en las seis localidades con niveles elevados de glutatión S-transferasas (GSTs, monooxigenasas y esterasas, y a pirimifos metil en La Unión con una alta frecuencia de la acetilcolinesterasa (AChE alterada. CONCLUSIÓN: Las poblaciones de An. albimanus colectadas al sur de la PY son resistentes al DDT y deltametrina, y en La Unión además al pirimifos metil, con mecanismos basados en la AChE alterada para el pirimifos metil, GST para DDT, y monooxigenasas y esterasas para piretroides. Los resultados del presente estudio tienen importantes consecuencias prácticas para el control químico de An. albimanus en el sur de la PY.OBJECTIVE: To diagnose susceptibility levels and insecticide resistance mechanisms in Anopheles albimanus from the southern Yucatan Peninsula (YP, Mexico. MATERIAL AND METHODS: F1 generation of An. albimanus females, collected from November to December 2005 in six villages in the Othon P. Blanco municipality in Quintana Roo and the Calakmul municipality in Campeche, were exposed to deltamethrin, DDT, pirimiphos-methyl and bendiocarb in susceptibility tests, as well as to biochemical assays in order to calculate the enzyme levels related to insecticide resistance. RESULTS: High levels of DDT and deltamethrin resistance were found in An. albimanus collected from the six villages, and a high resistance to pirimiphos-methyl was found in those from La

  13. [Epidemiologic and molecular study of Entamoeba histolytica and Entamoeba dispar strains in pacients with diarrhea in Cumana, Sucre state, Venezuela].

    Science.gov (United States)

    Mora, Leonor; García, Ana; De Donato, Marcos; Urdaneta, Haideé

    2008-06-01

    An epidemiological and molecular study on E. histolytica and E. dispar was carried out in 428 patients with gastrointestinal symptomatology of diarrhea from different health centers in Cumana, Sucre state. The samples were processed through: direct examination with 0.85% physiological saline solution, temporal lugol staining, trichromic staining and the Ritchie method of concentration; a sucrose gradient was used for cyst isolation. The small subunit of the 16S RNA was amplified by nested, multiplex PCR for the molecular detection. The E. histolytica/E. dispar prevalences according to the direct, Ritchie and trichromic staining methods were 20.09, 13.79 and 12.15%, respectively; while prevalences according to PCR for E. histolytica and E. dispar were 6.31% and 4.44%, respectively, also detecting four cases of mixed infection. Sequencing of the amplified fragments of E. histolytica showed 100% homology with the sequences with strains from Merida (Venezuela), USA, Brazil, Mexico and GenBank. The infections by E. histolytica and E. dispar were statistically associated with age but not with sex. The presence of mucus, blood and abdominal pain were only associated to E. histolytica infection. The moderate prevalence of E. histolytica shows the endemic status of this population and warns about the potential problem as a morbidity and mortality in Sucre state. The frequency of E. dispar in this population suggests the existence of an overestimation problem in the diagnosis of amoebiasis with its clinical and epidemiological implications, and shows the poor knowledge about the true prevalences of this protozoan. The PCR allowed for the differential identification of E. histolytica and E. dispar, as well as the presence of mixed infections, making a great tool for epidemiological amoebiasis studies.

  14. Emissions from biomass burning in the Yucatan

    Science.gov (United States)

    R. J. Yokelson; J. D. Crounse; P. F. DeCarlo; T. Karl; S. Urbanski; E. Atlas; T. Campos; Y. Shinozuka; V. Kapustin; A. D. Clarke; A. Weinheimer; D. J. Knapp; D. D. Montzka; J. Holloway; P. Weibring; F. Flocke; W. Zheng; D. Toohey; P. O. Wennberg; C. Wiedinmyer; L. Mauldin; A. Fried; D. Richter; J. Walega; J. L. Jimenez; K. Adachi; P. R. Buseck; S. R. Hall; R. Shetter

    2009-01-01

    In March 2006 two instrumented aircraft made the first detailed field measurements of biomass burning (BB) emissions in the Northern Hemisphere tropics as part of the MILAGRO project. The aircraft were the National Center for Atmospheric Research C-130 and a University of Montana/ US Forest Service Twin Otter. The initial emissions of up to 49 trace gas or particle...

  15. NIVELES SÉRICOS DE MAGNESIO, HIERRO Y COBRE EN POBLACIÓN DE ADULTOS DE CIUDAD BOLÍVAR, ESTADO BOLÍVAR, VENEZUELA I SERUM LEVELS OF MAGNESIUM , IRON AND COPPER IN ADULT POPULATION FROM CIUDAD BOLIVAR, BOLIVAR STATE, VENEZUELA

    Directory of Open Access Journals (Sweden)

    María Caride

    2014-02-01

    Full Text Available Determination of bioelements concentrations in serum are considered very important, since they allow to establish reference levels that can be used to detect essential elements deficiency or poisoning by their excess. The aim of this study was to identify the serum levels of magnesium, iron and copper in a population of apparently healthy adults, residents of an urban area of Ciudad Bolivar, Bolivar State, The sample consisted of 57 individuals (28 men and 29 women that were not occupationally exposed residents in Ciudad Bolivar, aged between 25 and 60 years. Bioelements were determined by Inductively Coupled Plasma Optical Emission Spectrometry (ICP-OES after acid digestion of serum samples. The average concentration values (± SD of magnesium, iron and copper obtained were, respectively, 22 ± 3 mg.L-1, 1.1 ± 0.2 mg.L-1 y 1.0 ± 0.2 mg.L-1. Regarding the studied bioelement levels, only magnesium levels of men were significantly higher (p < 0.05 than the levels of women. The mean concentrations of bioelements were within ranges of reference values reported in the literature for healthy people, but significantly different (p < 0,05 to those from Merida, another region from Venezuela, and a possible consequence of changes in eating habits and environment conditions among these two Venezuelan regions.

  16. Military Support to Law Enforcement Agencies Along the United States Southwestern Border

    Science.gov (United States)

    2011-06-10

    the Military. There are numerous resources available discussing the Merida Initiative developed along the same lines as Plan Colombia was in previous...all US cocaine transits Mexico. Mexico is also the dominant source of methamphetamine production for the US market . The drug cartels have criminal...low wages makes the Mexican employees an easy target for cartels. A recent study of pharmaceutical shipment thefts found that 65 percent of the

  17. BOVINE RESPIRATORY SYNCYTIAL VIRUS EPIDEMIOLOGY AND RISK FACTORS ON CATTLE HERDS OF CAMPECHE STATE, MEXICO

    Directory of Open Access Journals (Sweden)

    Lisandro Alberto Encalada Mena

    2016-12-01

    Full Text Available High seroprevalence in Yucatan and proximity to the state of Campeche make it necessary to determine the seroprevalence and risk factors of bovine respiratory syncytial virus (VRSB in the state of Campeche, Mexico. Thus the objective of the present work was to determine the seroprevalence and risk factors bovine respiratory syncytial virus (BRSV of the state of Campeche, Mexico. The sampled of 36 cattle herds (842 sera were analyzed by indirect ELISA kit, in the 11 municipalities of Campeche. A survey to obtain risk factors (sex, age of animals, number of animals grazing density, management system, presence of sheep on the farm and access to the roadside was applied and calculated X2 for each variable considered. Of the total number of samples analyzed (842, 273 were positive (32.47%. The prevalence ranges found ranged from 0% to 84%, so in 9 of the herds there were no positive samples, indicating a 75% (27/36 of dispersion of this virus. X2 analysis indicated that all variables were significant and are risk factors regarding with respect to the variable seroprevalence of BRSV. The results indicate a wide circulation of BRSV and we suggest implement recommendations that will enable a lower spread of this virus in the cattle population.

  18. Student Travel to Pan-Am Congress of Plants & Biofuels in Merida, Mexico

    Energy Technology Data Exchange (ETDEWEB)

    Kimberly, Kimnach [American Society of Plant Biologists, Rockville, MD (United States)

    2014-04-01

    The Pan American Congress on Plants and BioEnergy convened in Mérida, Mexico, June 22 to 25, 2008. The program was organized by Steve Long (University of Illinois) and Nick Carpita (Purdue University), along with co-organizers Marcos Buckeridge (University of São Paulo, Brazil) and Federico Sánchez (Universidad Nacional Autónoma de México). More than 200 scientists from over a dozen nations around the world gathered to discuss key issues surrounding the development of biofuel feedstocks and to report on their research in this area. This three day conference had invited speakers surrounding developing renewable and sustainable energy resources which are typically propelled by three important drivers – security, cost and environmental impact.

  19. Rethinking Merida’s Priorities: The Time is Now to Invest in Homeland Security

    Science.gov (United States)

    2011-10-28

    reduction. Mark Kleiman , Professor of Public Policy at UCLA, articulates this viewpoint, noting, “the basic problem is not supply from Mexico but demand...Report to Congressional Requesters (Washington, DC: U.S. Government Accountability Office, July 2010), 36. 27 Mark Kleiman , “Surgical Strikes in the...Washington, DC: Congressional Research Service, 2008. Kleiman , Mark. “Surgical Strikes in the Drug Wars: Smarter Policies for Both Sides of the

  20. U.S.-Mexican Security Cooperation: the Merida Initiative and Beyond

    Science.gov (United States)

    2010-08-16

    Nueva Paradigma de Cooperación Entre México y Estados Unidos en Seguridad ? Mexico City : National Autonomous University of Mexico, 2009. 29 Ibid; see...press, particularly in parts of Mexico where attacks on journalists have led to virtual self-censorship.99 Still others, including U.S. officials...Trafficking Group, the Weapons Virtual Task Force, and the ICE Border Liaison Program. Operation Against Smugglers (and Traffickers) Initiative on Safety

  1. Expectations and Perceptions of the Educational Service at the Universidad Nacional Abierta (Local Center Merida, Venezuela

    Directory of Open Access Journals (Sweden)

    Teresa de Jesús Molina Gutiérrez

    2017-08-01

    Full Text Available The objective of this study was to interpret the relationship between the expectations and the perceptions that the staff has about the quality of the educational service offered at the Mérida Local Center (Universidad Nacional Abierta, then the conceptual model of quality of service SERVQUAL, complemented with the qualitative approach. The informants were 15 advisors, 20 students and 5 administrative staff, the data were collected through the semi-structured interview and interpreted with the content analysis. The results indicate that there is no satisfaction with the educational service or that satisfaction is very low, because the expectations that are generated before receiving it are not surpassed by the perceived value, which is an indicator of the absence of quality of service. On the other hand, achieving quality in the service provided is the responsibility of all involved since the complexity of the roles fulfilled in the educational dialectic means that the staff act simultaneously as clients and as service providers.

  2. Rapunzel Loves Merida: Melodramatic Expressions of Lesbian Girlhood and Teen Romance in Tangled, Brave, and Femslash.

    Science.gov (United States)

    Kapurch, Katie

    2015-01-01

    This article explores the melodramatic expression of lesbian girlhood and teen romance in Disney's Tangled (2010) and Disney Pixar's Brave (2012), as well as "Meripunzel" femslash, fan-authored romantic pairings of the animations' female protagonists. First, Anne Sexton's poem, "Rapunzel," offers a literary precedent for exploring lesbian themes in the fairy tale. The next section shows how Tangled and Brave invoke the narrative conventions of the family melodrama. This generic association reveals the films' uses of rhetoric familiar to youth coming-out narratives, as well as other visual and aural coding suggestive of queer styles. The last section shows how Meripunzel femslash taps into the films' existing melodramatic narrative forms and visual aesthetics, rehearsing their coming-out rhetoric while addressing the pleasures of and problems facing lesbian teen romance. I conclude by problematizing the often conventional expressions of lesbian girlhood in femslash, ultimately arguing for their empowering potential, especially as they indicate revised definitions of "princess."

  3. Crisis in Mexico: Assessing the Merida Initiative and its Impact on Us-Mexican Security

    Science.gov (United States)

    2009-04-01

    corruption within the police force. There are four main reasons for police corruption. First, they have no minimum education requirement so most...police officers are poorly educated with an elementary school education or less. The second major issue is training. Institutional support for...dominated by the Institutional Revolutionary Party (Partido Revolucionario Institucional , PRI) since 1938. The PRI was founded on a revolutionary

  4. Beyond Merida: A Cooperative Counternarcotics Strategy for the 21st Century

    Science.gov (United States)

    2011-10-28

    arrest, and prosecute offenders . To do otherwise would be un-American. Drug interdiction and crop eradication efforts also appeal to many because of...in education and infrastructure as well as corruption and drug- related crime organizations. Opponents of these ideas may point to the enormous...augment efforts to interdict narcotics trafficking. Hawaii’s Opportunity Probation with Enforcement Program (HOPE), which focuses on reducing drug

  5. Health and nutritional status in Mérida, México: A population-based study

    Directory of Open Access Journals (Sweden)

    Enrique Efraín Barbosa-Martín

    2016-09-01

    Full Text Available Introduction: The Health and Nutrition National Survey (ENSANUT reports the panorama of the national and state nutritional epidemiology in Mexico. However, there are no reports of the capital cities of the country. The objective of this report was to evaluate the health and nutritional condition in a sample of the population of Merida, Yucatan, Mexico. Material and Methods: Transversal, retrospective and descriptive study that used the methodological and diagnostic guidelines of ENSANUT, WHO and Official Mexican Standards. To know malnutrition, normal weight and overweight prevalence, hypertension probable cases (CPHA and diabetes mellitus probable cases (CPDM were determined and anthropometric measurements were performed. SPSS 20.0 and Excel 2013 were used to calculate proportions and the results were expressed in prevalence. Results: 4,324 subjects were evaluated (644 pre-school pupils, 1,881 school pupils, 133 adolescents and 1,666 adults. In adults the prevalence of CPHA and CPDM were 11.8% and 10.2%, respectively. For pre-school pupils the prevalence of low weight, emaciation and low height were 0.4%, 0.7% and 2.7%, respectively. For school pupils, adolescents and adults malnutrition prevalence was 3.3%, 2.2% and 1.2% respectively. The prevalence of normal weight and overweight in pre-school pupils, school pupils, adolescents and adults was 54.6%, 45.5%, 48.1%, 20.7% and 16.1%, 51%, 49.5% y 77.9%, respectively. Conclusions: High prevalence of diabetes mellitus probable cases in men and low prevalence of malnutrition in all ages were observed. The prevalence of overweight in pre-school pupils, school pupils and adolescents was higher than the national and estate average.

  6. State Fairgrounds

    Data.gov (United States)

    Department of Homeland Security — This shapefile is a point shapefile that displays the locations of the major state/regional agricultural fairs held throughout the United States. Some states (e.g.,...

  7. FAILED STATE

    African Journals Online (AJOL)

    Dr. Miles R. Cone

    the state, it is possible to extrapolate a core of characteristics usually included in definitions of the state. .... colonial history is the 'artificial nature' of Africa's state borders and the notion that statehood was imposed on .... increasingly work exclusively for their own benefit as the state's capacity gradually weakens. Key interest ...

  8. Payment - State

    Data.gov (United States)

    U.S. Department of Health & Human Services — Payment measures – state data. This data set includes state-level data for the payment measures associated with an episode of care for heart attack, heart failure,...

  9. Payment - State

    Data.gov (United States)

    U.S. Department of Health & Human Services — Payment measures – state data. This data set includes state-level data for the payment measures associated with an episode of care for heart attack, heart failure,...

  10. Supersqueezed states from squeezed states

    International Nuclear Information System (INIS)

    Nieto, M.M.

    1992-01-01

    Using super-Baker-Campbell-Hausdorff relations on the elements of the supergroup OSP(2/2), we derive the supersqueeze operator and the supersqueezed states, which are the supersymmetric generalization of the squeezed states of the harmonic oscillator

  11. Excited states

    CERN Document Server

    Lim, Edward C

    1974-01-01

    Excited States, Volume I reviews radiationless transitions, phosphorescence microwave double resonance through optical spectra in molecular solids, dipole moments in excited states, luminescence of polar molecules, and the problem of interstate interaction in aromatic carbonyl compounds. The book discusses the molecular electronic radiationless transitions; the double resonance techniques and the relaxation mechanisms involving the lowest triplet state of aromatic compounds; as well as the optical spectra and relaxation in molecular solids. The text also describes dipole moments and polarizab

  12. State Publications.

    Science.gov (United States)

    Jobe, Janita

    1992-01-01

    This annotated bibliography lists 100 state government documents from 45 states published in 1991 that address a wide range of topics, including historical and cultural issues; health and social issues, including education, crime, and homelessness; the environment; and the economy. A list of contributors is included. (two references) (MES)

  13. Population structure and sexual maturity of the calico box crab Hepatus epheliticus Linnaeus (Brachyura, Hepatidae from Yucatan Peninsula, Mexico Estructura poblacional y madurez sexual en el cangrejo caja moteado Hepatus epheliticus Linnaeus (Brachyura, Hepatidae procedente de la Península del Yucatán, México

    Directory of Open Access Journals (Sweden)

    Patricio Hernáez

    2012-07-01

    Full Text Available The calico box crab Hepatus epheliticus is an abundant species from shallow and continental shelf waters of the Atlantic coast of USA and Mexico. Information about population structure and sexual maturity is absent, even though this crab is caught to be used as bait for the octopus fishery in the Campeche Bank, Mexico. In order to achieve such information, a total of 768 individuals were collected from January to March 2010 through baited traps installed in the Yucatan Peninsula, Mexico. Our results showed that sex ratio is biased towards more males than females (1:0.55, contradicting to that reported in other brachyuran crabs. The absence of ovigerous females suggests that they did not enter into the traps during embryogenesis. Males reached a larger maximum size than females (64.0 ± 6.15 and 58.4 ± 5.60 mm carapace width, respectively. The general scheme of growth being positive allometric throughout ontogeny of both sexes. Males presented a transition phase from juveniles to adult corresponding to the puberty moult. The estimation of the onset of functional sexual maturity revealed a steady situation for the population, with 21.5 and 13.8% of males and females, respectively, morphologically immature at the time of catch. This study constitutes the first report on population structure and sexual maturity in a population of the calico box crab H. epheliticus.El cangrejo caja moteado Hepatus epheliticus es un abundante braquiuro perteneciente a la familia Hepatidae, distribuido desde aguas someras hasta la plataforma continental en la costa atlántica de Estados Unidos y México. La información sobre su demografía poblacional y madurez sexual es actualmente inexistente, aun cuando esta especie es intensamente capturada como carnada en la pesquería del pulpo del estado de Campeche, México. Entre enero y marzo de 2010, se colectaron 768 especímenes usando trampas instaladas en la Península de Yucatán, México. Los resultados mostraron una

  14. The histopathology of cutaneous leishmaniasis due to Leishmania (Leishmania mexicana in the Yucatan peninsula, Mexico Histopatologia de la leishmaniasis cutánea causada por Leishmania (Leishmania mexicana en la península de Yucatán, México

    Directory of Open Access Journals (Sweden)

    Fernando J. Andrade-Narvaez

    2005-08-01

    Full Text Available Localized Cutaneous Leishmaniasis (LCL known as "chiclero's ulcer" in southeast Mexico, was described by SEIDELIN in 1912. Since then the sylvatic region of the Yucatan peninsula has been documented as an endemic focus of LCL. This study of 73 biopsies from parasitological confirmed lesions of LCL cases of Leishmania (Leishmania mexicana infection was undertaken: 1 to examine host response at tissue level; and 2 to relate manifestations of this response to some characteristics of clinical presentation. Based on Magalhães' classification we found that the most common pattern in our LCL cases caused by L. (L. mexicana was predominantly characterized by the presence of unorganized granuloma without necrosis, (43.8%. Another important finding to be highlighted is the fact that in 50/73 (68.5% parasite identification was positive. There was direct relation between the size of the lesion and time of evolution (r s = 0.3079, p = 0.03, and inverse correlation between size of the lesion and abundance of amastigotes (r s = -0.2467, p = 0.03. In view of the complexity of clinical and histopathological findings, cell-mediated immune response of the disease related to clinical and histopathological features, as so genetic background should be studied.La Leishmaniosis Cutánea Localizada (LCL mejor conocida como "úlcera del chiclero" en el sureste de México fue descrita por SEIDELIN en 1912. Desde entonces la región selvática de la península de Yucatán ha sido identificada como un área endémica de LCL. En el presente estudio se analizaron 73 biopsias de lesiones de casos de LCL causados por Leishmania (Leishmania mexicana con el fin de: 1 examinar la respuesta a nivel tisular; y 2 relacionar las manifestaciones de esta respuesta con ciertas características de la presentación clínica. Con base en la clasificación histopatológica de Magalhães el patrón histopatológico más frecuente se caracterizó por la presencia de granuloma desorganizado y

  15. Chitons (Mollusca, Polyplacophora from Alacranes Reef, Yucatan, Mexico

    Directory of Open Access Journals (Sweden)

    Adriana Reyes-Gómez

    2017-04-01

    Full Text Available This study represents the first comprehensive chiton study from Alacranes Reef, the largest reef system in the Gulf of Mexico. Nine chiton species were found in seven localities within the area, in the intertidal and subtidal to 12 m depth. SEM examination of C. janeirensis, A. hemphilli, T. schrammi and C. floridanus, showed variations in the sculpture and radular teeth morphology when compared to specimens of the same species from Florida Keys, Bahamas and Puerto Rico. The distribution ranges of T. schrammi, L. liozonis and S. floridana are extended into the south-western area of the Gulf of Mexico. Altogether, combining previous literature and the present survey, reports eleven chiton species which have now been recorded within the Alacranes reef area.

  16. Beekeeping, environment and modernity in localities in Yucatan, Mexico

    Directory of Open Access Journals (Sweden)

    Enrique Rodríguez Balam

    2015-09-01

    Full Text Available In this paper, we reflect on the local knowledge about the European honey bee Apis mellifera scutellata, namely its biology, behavior, social structure, communication, and the relationships that these organisms maintain with the environment and their natural enemies. We also discuss the impacts that land use has on this economic activity. The empirical knowledge of beekeepers converges quite well with the scientific knowledge concerning this group of organisms.

  17. Recent Carbonate Sedimentation on Alacran Beef, Yucatan, Mexico.

    Science.gov (United States)

    Hard parts from marine organisms composed or aragonite and calcite, and a trace of siliceous particles from Recent surface sediments on Alacran Reef...grain-type composition. Nearly all sub merged sediments are poorly sorted, and most are coarse-skewed andkurtic. The averaged sand fraction of Alacran

  18. Chitons (Mollusca, Polyplacophora) from Alacranes Reef, Yucatan, Mexico

    Science.gov (United States)

    Reyes-Gómez, Adriana; Ortigosa, Deneb; Simões, Nuno

    2017-01-01

    Abstract This study represents the first comprehensive chiton study from Alacranes Reef, the largest reef system in the Gulf of Mexico. Nine chiton species were found in seven localities within the area, in the intertidal and subtidal to 12 m depth. SEM examination of C. janeirensis, A. hemphilli, T. schrammi and C. floridanus, showed variations in the sculpture and radular teeth morphology when compared to specimens of the same species from Florida Keys, Bahamas and Puerto Rico. The distribution ranges of T. schrammi, L. liozonis and S. floridana are extended into the south-western area of the Gulf of Mexico. Altogether, combining previous literature and the present survey, reports eleven chiton species which have now been recorded within the Alacranes reef area. PMID:28769624

  19. Emissions from biomass burning in the Yucatan [Discussions

    Science.gov (United States)

    R. Yokelson; J. D. Crounse; P. F. DeCarlo; T. Karl; S. Urbanski; E. Atlas; T. Campos; Y. Shinozuka; V. Kapustin; A. D. Clarke; A. Weinheimer; D. J. Knapp; D. D. Montzka; J. Holloway; P. Weibring; F. Flocke; W. Zheng; D. Toohey; P. O. Wennberg; C. Wiedinmyer; L. Mauldin; A. Fried; D. Richter; J. Walega; J. L. Jimenez; K. Adachi; P. R. Buseck; S. R. Hall; R. Shetter

    2009-01-01

    In March 2006 two instrumented aircraft made the first detailed field measurements of biomass burning (BB) emissions in the Northern Hemisphere tropics as part of the MILAGRO project. The aircraft were the National Center for Atmospheric Research C-130 and a University of Montana/US Forest Service Twin Otter. The initial emissions of up to 49 trace gas or particle...

  20. State Antifeminism

    Directory of Open Access Journals (Sweden)

    Francis Dupuis-Déri

    2016-06-01

    Full Text Available ‘State feminism’ is a concept that refers to the integration of feminists and feminist issues into the state apparatus. Yet, while the feminist movement must regularly contend with an antifeminist counter-movement, it is worth considering whether a ‘state antifeminism’ is also present or emerging, and how this presence or emergence is affecting efforts by feminist organizations to address the needs of women and advance women's equality. With this objective in mind, this article focuses chiefly on two Western countries and is based on more than twenty semi-structured interviews with feminists in Belgium and Quebec, Canada.

  1. State Climatologist

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Quarterly newsletter published by the American Association of State Climatologists. Library includes volumes 1 through 21, for the years 1977-1997.

  2. HCAHPS - State

    Data.gov (United States)

    U.S. Department of Health & Human Services — A list of the state averages for the HCAHPS survey responses. HCAHPS is a national, standardized survey of hospital patients about their experiences during a recent...

  3. State Averages

    Data.gov (United States)

    U.S. Department of Health & Human Services — A list of a variety of averages for each state or territory as well as the national average, including each quality measure, staffing, fine amount and number of...

  4. The United Nations Convention against Corruption. A Primer for Development Practitioners

    OpenAIRE

    Schultz, Jessica

    2007-01-01

    The United Nations Convention against Corruption (UNCAC), adopted in Merida, Mexico in 2003, represents a remarkable achievement for international anti-corruption efforts. With endorsements from more than 140 state signatories representing every region of the world, the UNCAC offers a comprehensive, global framework for combating corruption.

  5. Rydberg states

    International Nuclear Information System (INIS)

    Brouillard, F.

    1983-01-01

    This chapter considers the formation of Rydberg atoms; their radiative decay; their behavior in electric and electromagnetic fields; and their collisions with atoms and ions. Discusses electron capture into high excited states; laser excitation of Rydberg states; Stark shift and Stark mixing; field ionization; ionization in oscillating fields; thermal collisions of Rydberg atoms; fast collisions of Rydberg atoms; n-changing collisions; and charge exchange. Points out that a large amount of experimental work has been done on collisions of Rydberg atoms with neutral perturbers at thermal energies, and most of it concerns the destruction of Rydberg alkali atoms in collisions with rare gases

  6. RIVER STATE

    African Journals Online (AJOL)

    The aim of this study was to investigate the influence of gender on leadership styles and administrative effective~~ess of secondary school principals in selected sctiools in Cross River State. In pursuance of this study, two hypothesis were formulated. Two sets of questionnaires, Principal's Self-Evaluation. Questionnaire ...

  7. State Treasure

    Science.gov (United States)

    Olson, Cathy Applefeld

    2013-01-01

    When a music teacher is named Teacher of the Year for an entire state, one just know a special story awaits. The narrative of Heidi Welch, director of music at Hillsboro-Deering High School in New Hampshire, does not disappoint. Welch, who grew up in abject poverty and was often homeless, developed her love of music through memorizing and singing…

  8. Altered States

    International Development Research Centre (IDRC) Digital Library (Canada)

    (To raise a government's revenues, for example, or to propose a government expenditure, is first to judge the tolerance of the global bond market and the mood swings of currency traders.) Meanwhile, the transcending, supranational issues of peace, development, and the preservation of the planet defy resolution by states ...

  9. RIVER STATE

    African Journals Online (AJOL)

    The aim of this study was to investigate the influence of gender on leadership styles and administrative .... ranked significantly ahead of men as democratic leaders ... effectiveness and leadership styles of secondary school principals In Cross River. State. METHODOLOGY. Research Area: The study was conducte'd in c ~ m.

  10. Korean Studies in Mexico: A Survey and Recommendations

    Directory of Open Access Journals (Sweden)

    Won-Ho Kim

    2011-08-01

    Full Text Available Some 1,033 Koreans left Jemulpo (Today Inchon port for Mexico in April 4, 1905, and arrived about 40 days later in Merida, Yucatan. They were first Korean immigrants to Mexico, arranged by a Japanese colonial company but actually sold as slaves to work in twenty-four henequen farms in nearby Chench, Za-Chil, etc. Frustrated with the miserable life there and suffering from the tumultuous Mexican Revolution (1910-1917, many of them attempted to escape and ultimately moved to Cuba. It is estimated that more than two thousand Korean descendants from the first immigrants live in Mexico and about eight hundred in Cuba. The immigration was the first contact between Mexico and Korea.

  11. Low prevalence of high risk human papillomavirus in normal oral mucosa by hybrid capture 2 Baixa prevalência de papilomavírus humano de alto risco na mucosa oral normal através de Captura Híbrida 2

    Directory of Open Access Journals (Sweden)

    Maria del Refugio González-Losa

    2008-03-01

    Full Text Available High risk human papillomavirus (HR-HPV are recognized as a necessary factor to development cervical cancer. During the last decade many studies have found HR-HPV in oral squamous cell carcinoma (OSCC and normal oral mucosa, however the association between HR-HPV and OSCC is still uncertain. The aim of the study was to determine DNA HR-HPV in normal oral cavity of healthy adults. A cross-sectional study was performed; samples from 77 patients with normal oral cavity were collected at the Dentistry school, Autonomous University of Yucatan, Merida, Yucatan, México. HR-HPV was detected by hybrid capture 2. One sample out of 77(1.2% was positive for HR-PVH. It was from a man of 50 years old. HR-HPV is present in low rate among healthy oral mucosa. Hybrid capture 2 could be a good methodology for large epidemiology studies.Papilomavírus humano de alto risco (HR-HPV é um fator reconhecido como necessário para o desenvolvimento de câncer cervical. Na última década vários estudos encontraram HR-HPV em OSCC (oral squamous cell carcinoma e em mucosa oral normal, mas a associação entre HR-HPV e OSCC não é bem conhecida. O objetivo desse estudo foi determinar DNA de HR-HPV na cavidade oral normal de adultos saudáveis. Realizou-se um estudo cross-sectional com amostras da cavidade oral normal de 77 pacientes da Escola de Odontologia da Autonomous University of Yucatan, Merida, Yucatan, México. HR-HPV foi detectado através de Captura Híbrida 2. Uma amostra em 77 (1,2% foi positiva para HR-PVH e era proveniente de um homem de 50 anos de idade. Concluiu-se que HR-HPV tem baixa prevalência na mucosa oral normal e a Captura Híbrida 2 pode ser um método adequado para estudos epidemiológicos.

  12. State of the States 2016: Arts Education State Policy Summary

    Science.gov (United States)

    Aragon, Stephanie

    2016-01-01

    The "State of the States 2016" summarizes state policies for arts education identified in statute or administrative code for all 50 states and the District of Columbia. Information is based on a comprehensive search of state education statute and codes on each state's relevant websites. Complete results from this review are available in…

  13. Salinity proxy comparison in four tropical biogenic carbonates for suitability in paleohydrologic reconstruction

    Science.gov (United States)

    Broach, K.; Paytan, A.; Street, J. H.

    2014-12-01

    Climate change is expected to increasingly stress water resources in drought-prone areas such as the American Southwest or Central America. Understanding patterns in precipitation frequency and intensity in the recent past are critical to accurately modeling groundwater recharge potential and managing diminishing resources in conjunction with rapid urbanization (e.g. Yucatan, Mexico). Wet and dry seasons on the Yucatan Peninsula are affected by the Intertropical Convergence Zone (ITCZ) which can exacerbate drought as the climate warms. This study focuses on precipitation patterns during the late Holocene recorded in foraminifera (Ammonia beccarii, Elphidium sp., Quinqueloculina sp.) and ostracods (suspected Hemicyprideis nichuptensis) along a transect in Celestun Lagoon near Merida, Yucatan, Mexico. Submarine groundwater springs feed the north terminus of the lagoon resulting in δ18O and Mg gradients toward the ocean which oscillate in response to increased or decreased precipitation. Mg/Ca ratios from the north (4.59) and south (3.08) lagoon suggest warmer waters in the shallow northern end, resulting in evaporation and confounding the δ18O values there (upper lagoon = 2.1‰, middle lagoon = 0.3‰, lower lagoon = 1.5‰). B/Ca ratios remain fairly constant (average range 27.3-33.2) despite increasing B concentrations toward the southern mouth, suggesting a concurrent increase in dissolved calcium down the lagoon and thus a lower Ca signal in spite of the karst source of springs. Of the four species tested, A. beccarii and H. nichuptensis yielded the most similar results ([Ca] ~ 150 ppm). Replicate analyses are needed for Elphidium sp. and Quinqueloculina sp. due to their low sample size and signal variability which suggests they may not be ideal candidates for paleoenvironmental reconstruction in Celestun Lagoon and possible other marginal environments around the Yucatan Peninsula.

  14. United States

    Directory of Open Access Journals (Sweden)

    Stephen Bernow

    1998-12-01

    Full Text Available This paper presents and discusses an integrated set of policies designed to reduce U.S. carbon emissions over the next four decades. This innovation path also aims to promote environmental quality, particularly by reducing emissions of criteria air pollutants, to reduce U.S. dependence on imported oil, and to induce technological innovation and diffusion in energy production and consumption. The innovation path would reduce economy-wide carbon emissions by 26% below baseline projections for 2010 and by 62% below baseline projections for 2030; this translates into 10% below 1990 levels in 2010 and 45% below 1990 levels in 2030. Emissions of criteria pollutants also would be significantly reduced, as would petroleum imports by the United States. Moreover, the innovation path would yield cumulative net savings for the United States of $218 billion (1993 dollars through 2010, or $19 billion on a leveled annual basis, and would result in 800,000 additional jobs nationwide by 2010. Although the overall findings from the innovation path analysis are robust, the results should be taken as indicative, rather than precisely predictive, owing to uncertainties in future costs, prices, technology performance, and consumer behavior.

  15. State of the States, 2012: Arts Education State Policy Summary

    Science.gov (United States)

    Arts Education Partnership (NJ1), 2012

    2012-01-01

    The "State of the States 2012" summarizes state policies for arts education identified in statute or code for all 50 states and the District of Columbia. Information is based primarily on results from the AEP Arts Education State Policy Survey conducted in 2010-11, and updated in April 2012.

  16. At same leucine intake, a whey/plant protein blend is not as effective as whey to initiate a transient post prandial muscle anabolic response during a catabolic state in mini pigs.

    Science.gov (United States)

    Revel, Aurélia; Jarzaguet, Marianne; Peyron, Marie-Agnès; Papet, Isabelle; Hafnaoui, Noureddine; Migné, Carole; Mosoni, Laurent; Polakof, Sergio; Savary-Auzeloux, Isabelle; Rémond, Didier; Dardevet, Dominique

    2017-01-01

    Muscle atrophy has been explained by an anabolic resistance following food intake and an increase of dietary protein intake is recommended. To be optimal, a dietary protein has to be effective not only to initiate but also to prolong a muscle anabolic response in a catabolic state. To our knowledge, whether or not a dairy or a dairy/plant protein blend fulfills these criterions is unknown in a muscle wasting situation. Our aim was, in a control and a catabolic state, to measure continuously muscle anabolism in term of intensity and duration in response to a meal containing casein (CAS), whey (WHEY) or a whey/ plant protein blend (BLEND) and to evaluate the best protein source to elicit the best post prandial anabolism according to the physio-pathological state. Adult male Yucatan mini pigs were infused with U-13C-Phenylalanine and fed either CAS, WHEY or BLEND. A catabolic state was induced by a glucocorticoid treatment for 8 days (DEX). Muscle protein synthesis, proteolysis and balance were measured with the hind limb arterio-venous differences technique. Repeated time variance analysis were used to assess significant differences. In a catabolic situation, whey proteins were able to initiate muscle anabolism which remained transient in contrast to the stimulated muscle protein accretion with WHEY, CAS or BLEND in healthy conditions. Despite the same leucine intake compared to WHEY, BLEND did not restore a positive protein balance in DEX animals. Even with WHEY, the duration of the anabolic response was not optimal and has to be improved in a catabolic state. The use of BLEND remained of lower efficiency even at same leucine intake than whey.

  17. At same leucine intake, a whey/plant protein blend is not as effective as whey to initiate a transient post prandial muscle anabolic response during a catabolic state in mini pigs.

    Directory of Open Access Journals (Sweden)

    Aurélia Revel

    Full Text Available Muscle atrophy has been explained by an anabolic resistance following food intake and an increase of dietary protein intake is recommended. To be optimal, a dietary protein has to be effective not only to initiate but also to prolong a muscle anabolic response in a catabolic state. To our knowledge, whether or not a dairy or a dairy/plant protein blend fulfills these criterions is unknown in a muscle wasting situation.Our aim was, in a control and a catabolic state, to measure continuously muscle anabolism in term of intensity and duration in response to a meal containing casein (CAS, whey (WHEY or a whey/ plant protein blend (BLEND and to evaluate the best protein source to elicit the best post prandial anabolism according to the physio-pathological state.Adult male Yucatan mini pigs were infused with U-13C-Phenylalanine and fed either CAS, WHEY or BLEND. A catabolic state was induced by a glucocorticoid treatment for 8 days (DEX. Muscle protein synthesis, proteolysis and balance were measured with the hind limb arterio-venous differences technique. Repeated time variance analysis were used to assess significant differences.In a catabolic situation, whey proteins were able to initiate muscle anabolism which remained transient in contrast to the stimulated muscle protein accretion with WHEY, CAS or BLEND in healthy conditions. Despite the same leucine intake compared to WHEY, BLEND did not restore a positive protein balance in DEX animals.Even with WHEY, the duration of the anabolic response was not optimal and has to be improved in a catabolic state. The use of BLEND remained of lower efficiency even at same leucine intake than whey.

  18. Trip Generation by Transportation Mode of Private School, Semi-private and Public. Case Study in Merida-Venezuela

    Energy Technology Data Exchange (ETDEWEB)

    Quintero Petit, A.M.; Diaz Gallardo, M.I.; Moreno Gonzalez, E.G.

    2016-07-01

    The trip generation model (TGM) is the first step in transportation forecasting, this is useful for estimating travel demand because it can predict travel from or to a particular land use. Typically, the analysis focuses in residential trip generation as a function of the social and economic attributes of households, but nonresidential land use suggests others variables. Travel generator poles such as: Private school, Semi-private and Public, have not been studied in Venezuela. The TGMs that shows the Institute of Transportation Engineers (ITE), EE.UU, are used typically and could be not appropriate. By using stepwise regression and transformation of data, high correlation coefficients and substantial improvements in the variability of data from several schools they were found. The trip generation rates (TGRs) by transportation mode: walking, motorcycle, public transport and cars, can be compared and be included in the Ibero-American Network of travel attractors poles. (Author)

  19. Household energy use in urban Venezuela: Implications from surveys in Maracaibo, Valencia, Merida, and Barcelona-Puerto La Cruz

    Energy Technology Data Exchange (ETDEWEB)

    Figueroa, M.J.; Sathaye, J.

    1993-08-01

    This report identifies the most important results of a comparative analysis of household commercial energy use in Venezuelan urban cities. The use of modern fuels is widespread among all cities. Cooking consumes the largest share of urban household energy use. The survey documents no use of biomass and a negligible use of kerosene for cooking. LPG, natural gas, and kerosene are the main fuels available. LPG is the fuel choice of low-income households in all cities except Maracaibo, where 40% of all households use natural gas. Electricity consumption in Venezuela`s urban households is remarkably high compared with the levels used in households in comparable Latin American countries and in households of industrialized nations which confront harsher climatic conditions and, therefore, use electricity for water and space heating. The penetration of appliances in Venezuela`s urban households is very high. The appliances available on the market are inefficient, and there are inefficient patterns of energy use among the population. Climate conditions and the urban built form all play important roles in determining the high level of energy consumption in Venezuelan urban households. It is important to acknowledge the opportunities for introducing energy efficiency and conservation in Venezuela`s residential sector, particularly given current economic and financial constraints, which may hamper the future provision of energy services.

  20. State Health Facts

    Science.gov (United States)

    ... State Health Facts Home State Health Facts Search State Health Facts: Choose Category - or - Choose Location Demographics ... Health Care Health Professional Shortage Areas (HPSAs) Featured State Data Resources Custom State Reports Compile data from ...

  1. Treating leachate by Fenton oxidation

    Directory of Open Access Journals (Sweden)

    Roger Iván Méndez Novelo

    2010-01-01

    Full Text Available Leachates are formed from liquids, mainly rainwater, percolating through solid wastes during stabilisation. Their composition is variable and highly toxic; leachate treatment is therefore a complex task. Leachates represent a high risk to health due to the Yucatan Peninsula’s highly permeable soil. The results are presented from applying the Fenton process to treating leachate from the sanitary Merida landfill, Yucatan, Mexico. The Fenton process consists of treating the contaminant load with an H2O2 and FeSO4 combination in acidic conditions. Optimal reaction time, pH value, Fenton reagent dose, post treatment coagulation – flocculation doses and increased biodegradability index were all determined. Optimal oxidation conditions and doses were 202+ minute contact time, 4 pH, 600 mg/L H2O2 concentration and 1,000 mg/L Fe. Average organic matter removal rate, measured as CODS and TOC, were 78% and 87% respectively. The biodegradability index increased from 0.07 to 0.11 during the Fenton process and up to 0.13 when the Fenton process was followed by coagulation-flocculation.

  2. A new species of predaceous midge of the genus Monohelea Kieffer from Mexico (Diptera: Ceratopogonidae).

    Science.gov (United States)

    Felippe-Bauer, M L; Huerta, H; Bernal, S I

    2000-01-01

    A description and illustrations of Monohelea maya, new species, based on male and female characteristics are provided. The specimens were collected in the special biosphere Reserves of Ria Lagartos and Ria Celestun, Yucatan State, Mexico.

  3. Rickettsia rickettsii isolation from naturally infected Amblyomma ...

    African Journals Online (AJOL)

    . rickettsii) and is transmitted by the bite of ticks of the genera Dermacentor, Amblyomma and Rhipicephalus. The illness results in a high mortality rate and may be easily confused with other febrile syndromes. In Yucatan State, Mexico, ...

  4. A new species of predaceous midge of the genus Monohelea Kieffer from Mexico (Diptera: Ceratopogonidae

    Directory of Open Access Journals (Sweden)

    Maria Luiza Felippe-Bauer

    2000-12-01

    Full Text Available A description and illustrations of Monohelea maya, new species, based on male and female characteristics are provided. The specimens were collected in the special biosphere Reserves of Ria Lagartos and Ria Celestun, Yucatan State, Mexico.

  5. Optimal resource states for local state discrimination

    Science.gov (United States)

    Bandyopadhyay, Somshubhro; Halder, Saronath; Nathanson, Michael

    2018-02-01

    We study the problem of locally distinguishing pure quantum states using shared entanglement as a resource. For a given set of locally indistinguishable states, we define a resource state to be useful if it can enhance local distinguishability and optimal if it can distinguish the states as well as global measurements and is also minimal with respect to a partial ordering defined by entanglement and dimension. We present examples of useful resources and show that an entangled state need not be useful for distinguishing a given set of states. We obtain optimal resources with explicit local protocols to distinguish multipartite Greenberger-Horne-Zeilinger and graph states and also show that a maximally entangled state is an optimal resource under one-way local operations and classical communication to distinguish any bipartite orthonormal basis which contains at least one entangled state of full Schmidt rank.

  6. Sweeping the State Space

    DEFF Research Database (Denmark)

    Mailund, Thomas

    The thesis describes the sweep-line method, a newly developed reduction method for alleviating the state explosion problem inherent in explicit-state state space exploration. The basic idea underlying the sweep-line method is, when calculating the state space, to recognise and delete states...... that are not reachable from the currently unprocessed states. Intuitively we drag a sweep-line through the state space with the invariant that all states behind the sweep-line have been processed and are unreachable from the states in front of the sweep-line. When calculating the state space of a system we iteratively...

  7. Ticks of Medical Importance Occurring in the Western Hemisphere

    Science.gov (United States)

    1987-10-01

    Mexico in the states of Baja California, Chiapas, Guerrero, Morelos, Oaxaca,. Puebla , Sinaloa, Sonora, Veracruz, and Yucatan (5). This species has also...in Mexico from the following states: Chiapas, Guanlajuato, Hidalgjo, O2axaca, Puebla , San Luis Potosi, Sonora, ramaulipas. and Yucatan (4). p’ p...1959). 64. Bustamante, M.E., and G. Varela. Une nueva rickettslosis en Mexico. Existencia do a& fiebra manchada americana en los estados do Sinaloa

  8. United States Department of State Strategic Plan

    Science.gov (United States)

    1998-01-01

    directs State’s public affairs strategy. (EB, Regional Bureaus, H, PA) • Conclude further "Open Skies" Civil Aviation agreements. Lead Agencies...State and Transportation. State heads interagency teams negotiating "Open Skies" and other civil aviation agreements. (EB, L, Regional Bureaus...Agency: State. CA, in coordination with A/ FBO , FS1 and overseas Missions, is developing new techniques to streamline consular workload and visa issuance

  9. State of the States in Developmental Disabilities

    Science.gov (United States)

    Braddock, David; Hemp, Richard; Rizzolo, Mary Kay

    2008-01-01

    This is the latest edition of the "State of the States in Developmental Disabilities" study--a thorough and the only one of its kind investigation on public spending, revenues, and programmatic trends of intellectual and developmental programs and services within the United States since 1977. Directed by leading researcher, Dr. David…

  10. José Martí, Viajes y Apreciación del Pueblo Maya

    Directory of Open Access Journals (Sweden)

    Carlos Eduardo Bojórquez Urzaiz

    2015-09-01

    Full Text Available Este trabajo expone y examina los cambios de percepción que experimentó José Martí sobre el papel de los pueblos originarios de América, entre 1875 y 1878, años en los que vivió en México y Guatemala, con intensa escala en Yucatán, lugares donde conoció directamente la cultura y el pueblo maya. Martí resume una visión inicial de nuestra América en la figura lítica de Chacmool cuando después de ser expropiada por el gobierno yucateco, el Apóstol cubano la admira en la ciudad de Mérida y expresa que es la síntesis de las culturas americanas. Aspecto poco estudiado en la obra de Martí es este acercamiento etnográfico a la realidad maya de Yucatán y Guatemala.   This paper aims at presenting and examining the change of perception José Martí underwent in relation to the role of the native peoples of America between 1875 and 1878, the years he lived in Mexico and Guatemala, during which he spent a large amount of time in Yucatan, where he was able to get to know the Mayan culture and its people first hand. Martí summarized his initial vision of our America in the lithic figure of Chacmool, which he was able to admire in the city of Merida, after it had been expropriated by the government of Yucatan. The Cuban apostle described this as a synthesis of American cultures. This ethnographic insight into the Mayan reality in Yucatan and Guatemala represents a scarcely explored aspect of Martí's work.

  11. State Park Trails

    Data.gov (United States)

    Minnesota Department of Natural Resources — This data set is a collection of ArcView shapefiles (by park) of trails within statutory boundaries of individual MN State Parks, State Recreation Areas and State...

  12. State Park Statutory Boundaries

    Data.gov (United States)

    Minnesota Department of Natural Resources — Legislative statutory boundaries for sixty six state parks, six state recreation areas, and eight state waysides. These data are derived principally from DNR's...

  13. Minimally conscious state or cortically mediated state?

    Science.gov (United States)

    Naccache, Lionel

    2018-04-01

    Durable impairments of consciousness are currently classified in three main neurological categories: comatose state, vegetative state (also recently coined unresponsive wakefulness syndrome) and minimally conscious state. While the introduction of minimally conscious state, in 2002, was a major progress to help clinicians recognize complex non-reflexive behaviours in the absence of functional communication, it raises several problems. The most important issue related to minimally conscious state lies in its criteria: while behavioural definition of minimally conscious state lacks any direct evidence of patient's conscious content or conscious state, it includes the adjective 'conscious'. I discuss this major problem in this review and propose a novel interpretation of minimally conscious state: its criteria do not inform us about the potential residual consciousness of patients, but they do inform us with certainty about the presence of a cortically mediated state. Based on this constructive criticism review, I suggest three proposals aiming at improving the way we describe the subjective and cognitive state of non-communicating patients. In particular, I present a tentative new classification of impairments of consciousness that combines behavioural evidence with functional brain imaging data, in order to probe directly and univocally residual conscious processes.

  14. State nuclear initiatives in the United States

    International Nuclear Information System (INIS)

    Strauss, P.L.; Stoiber, C.R.

    1977-01-01

    The paper deals with State nuclear initiatives regarding the role of nuclear power in the energy future of the United States. The question of whether and under what circumstances nuclear facilities should be used to generate electricity was put to the popular vote in several States in 1976. Some general principles of Federal-State relations are discussed with specific reference to nuclear regulations. The initiative mechanism itself is described as well as its legal form and background. The parallel developments in the State and Federal legislative consideration of nuclear issues is reviewed and the suggested reasons for the defeat of the proposals in the seven States concerned are discussed. Finally, the author draws some conclusions on the effects of the 1976 initiatives on future decision-making in the US on energy policy in general and nuclear power in particular. (NEA) [fr

  15. Photon virtual bound state

    International Nuclear Information System (INIS)

    Inoue, J.; Ohtaka, K.

    2004-01-01

    We study virtual bound states in photonics, which are a vectorial extension of electron virtual bound states. The condition for these states is derived. It is found that the Mie resonant state which satisfies the condition that the size parameter is less than the angular momentum should be interpreted as a photon virtual bound state. In order to confirm the validity of the concept, we compare the photonic density of states, the width of which represents the lifetime of the photon virtual bound states, with numerical results

  16. Quantum-state discrimination

    International Nuclear Information System (INIS)

    Roa, Luis; Retamal, Juan Carlos; Saavedra, Carlos

    2002-01-01

    A proposal for a physical implementation of a quantum-state discrimination protocol using an ion in a linear trap is studied, where two nonorthogonal quantum states are codified using two electronic states of the ion. In addition, a protocol is given for discriminating superpositions of nonorthogonal entangled states between ions inside widely separated optical cavities. The discrimination protocol is extended to the case of N linearly independent nonorthogonal quantum states lying in a space of 2N-1 dimensions

  17. Solid state video cameras

    CERN Document Server

    Cristol, Y

    2013-01-01

    Solid State Video Cameras reviews the state of the art in the field of solid-state television cameras as compiled from patent literature. Organized into 10 chapters, the book begins with the basic array types of solid-state imagers and appropriate read-out circuits and methods. Documents relating to improvement of picture quality, such as spurious signal suppression, uniformity correction, or resolution enhancement, are also cited. The last part considerssolid-state color cameras.

  18. State of the Air 2015

    Science.gov (United States)

    ... Press Releases Web Banners Social Media What's the State of Your Air ? Home > 2015 > States States State ... Report Report Card: What's the Grade for Your State? Search by Zip Code: Search by State: Or ...

  19. Product-State Approximations to Quantum States

    Science.gov (United States)

    Brandão, Fernando G. S. L.; Harrow, Aram W.

    2016-02-01

    We show that for any many-body quantum state there exists an unentangled quantum state such that most of the two-body reduced density matrices are close to those of the original state. This is a statement about the monogamy of entanglement, which cannot be shared without limit in the same way as classical correlation. Our main application is to Hamiltonians that are sums of two-body terms. For such Hamiltonians we show that there exist product states with energy that is close to the ground-state energy whenever the interaction graph of the Hamiltonian has high degree. This proves the validity of mean-field theory and gives an explicitly bounded approximation error. If we allow states that are entangled within small clusters of systems but product across clusters then good approximations exist when the Hamiltonian satisfies one or more of the following properties: (1) high degree, (2) small expansion, or (3) a ground state where the blocks in the partition have sublinear entanglement. Previously this was known only in the case of small expansion or in the regime where the entanglement was close to zero. Our approximations allow an extensive error in energy, which is the scale considered by the quantum PCP (probabilistically checkable proof) and NLTS (no low-energy trivial-state) conjectures. Thus our results put restrictions on the possible Hamiltonians that could be used for a possible proof of the qPCP or NLTS conjectures. By contrast the classical PCP constructions are often based on constraint graphs with high degree. Likewise we show that the parallel repetition that is possible with classical constraint satisfaction problems cannot also be possible for quantum Hamiltonians, unless qPCP is false. The main technical tool behind our results is a collection of new classical and quantum de Finetti theorems which do not make any symmetry assumptions on the underlying states.

  20. Adapting, Transforming, and Modernizing Under Fire: The Mexican Military 2006-11

    Science.gov (United States)

    2011-09-01

    of National Defense, Cuarto Informe de Labores (Ministry of National Defense), Fourth Annual Report 2006 -2012, p. 116. 17. Ibid.; Directiva General...2007-2012 [experimental]). 18. Ministry of National Defense, Cuarto Informe de Labores (Ministry of National Defense), Fourth Annual Report 2006 -2012...group”), Reforma , August 29, 2009. 22. Only December 2006 . 23. U.S. Department of State, Mexico-Merida Initiative report on Human Rights, August 2009

  1. U.S. Global Defense Posture, 1783-2011

    Science.gov (United States)

    2012-01-01

    Bajadas ( Veracruz ), Carmen, Campo Juanes (Merida), Cozumel, Chetumal, and Tehuantepec fields, Mexico; Camaguey and San Julian (Guane) fields, Cuba...payment often takes the form of eco- nomic or security assistance, especially arms sales . For instance, while mutual security considerations were the...granted the basing rights to the United States. Rather, the presence of economic assistance and arms sales often derived from the existence of an external

  2. Excited states v.6

    CERN Document Server

    Lim, Edward C

    1982-01-01

    Excited States, Volume 6 is a collection of papers that discusses the excited states of molecules. The first paper discusses the linear polyene electronic structure and potential surfaces, considering both the theoretical and experimental approaches in such electronic states. This paper also reviews the theory of electronic structure and cites some experimental techniques on polyene excitations, polyene spectroscopic phenomenology, and those involving higher states of polyenes and their triplet states. Examples of these experimental studies of excited states involve the high-resolution one-pho

  3. Quantifying matrix product state

    Science.gov (United States)

    Bhatia, Amandeep Singh; Kumar, Ajay

    2018-03-01

    Motivated by the concept of quantum finite-state machines, we have investigated their relation with matrix product state of quantum spin systems. Matrix product states play a crucial role in the context of quantum information processing and are considered as a valuable asset for quantum information and communication purpose. It is an effective way to represent states of entangled systems. In this paper, we have designed quantum finite-state machines of one-dimensional matrix product state representations for quantum spin systems.

  4. Drug Poisoning Mortality by State: United States

    Data.gov (United States)

    U.S. Department of Health & Human Services — This dataset describes drug poisoning deaths at the U.S. and state level by selected demographic characteristics, and includes age-adjusted death rates for drug...

  5. Complications and Deaths - State

    Data.gov (United States)

    U.S. Department of Health & Human Services — Complications and deaths - state data. This data set includes state-level data for the hip/knee complication measure, the Agency for Healthcare Research and Quality...

  6. State Program Integrity Reviews

    Data.gov (United States)

    U.S. Department of Health & Human Services — State program integrity reviews play a critical role in how CMS provides effective support and assistance to states in their efforts to combat provider fraud and...

  7. State transportation statistics 2009

    Science.gov (United States)

    2009-01-01

    The Bureau of Transportation Statistics (BTS), a part of DOTs Research and Innovative Technology Administration (RITA), presents State Transportation Statistics 2009, a statistical profile of transportation in the 50 states and the District of Col...

  8. State Water Districts

    Data.gov (United States)

    California Natural Resource Agency — State Water Project District boundaries are areas where state contracts provide water to the district in California. This database is designed as a regions polygon...

  9. Unplanned Hospital Visits - State

    Data.gov (United States)

    U.S. Department of Health & Human Services — Unplanned Hospital Visits – state data. This data set includes state-level data for the hospital return days (or excess days in acute care) measures, the unplanned...

  10. State Water Districts

    Data.gov (United States)

    California Department of Resources — State Water Project District boundaries are areas where state contracts provide water to the district in California. This database is designed as a regions polygon...

  11. Heart Attack Payment - State

    Data.gov (United States)

    U.S. Department of Health & Human Services — Payment for heart attack patients measure – state data. This data set includes state-level data for payments associated with a 30-day episode of care for heart...

  12. State Capitalism in Eurasia

    NARCIS (Netherlands)

    C. Spechler, Martin; Ahrens, Joachim; Hoen, Herman W.

    2017-01-01

    The book specifies the type of economic system that has arisen in Central Asian. It presents three types of state-capitalism established in the former Soviet Union states in Eurasia - crony, dual sector, and predatory capitalism.

  13. United States Pharmacopeial Convention

    Science.gov (United States)

    ... crisis. Learn More Containing drug costs in the United States The FDA is currently exploring a variety of ... Notices Privacy Policy Terms of Use Sitemap © The United States Pharmacopeial Convention ×

  14. STATE_SYSTEM

    Data.gov (United States)

    Kansas Data Access and Support Center — This dataset is a single centerline highway network representation of the 10,000 miles Kansas State Highway System (Interstate, U.S., and Kansas routes). The state...

  15. 7 CFR 1220.615 - State and United States.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false State and United States. 1220.615 Section 1220.615... CONSUMER INFORMATION Procedures To Request a Referendum Definitions § 1220.615 State and United States. State and United States include the 50 States of the United States of America, the District of Columbia...

  16. 7 CFR 1220.129 - State and United States.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false State and United States. 1220.129 Section 1220.129... CONSUMER INFORMATION Soybean Promotion and Research Order Definitions § 1220.129 State and United States. The terms State and United States include the 50 States of the United States of America, the District...

  17. 7 CFR 1209.21 - State and United States.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 10 2010-01-01 2010-01-01 false State and United States. 1209.21 Section 1209.21... Definitions § 1209.21 State and United States. (a) State means any of the several States, the District of Columbia, and the Commonwealth of Puerto Rico. (b) United States means collectively the several States of...

  18. Decay of Hoyle state

    Indian Academy of Sciences (India)

    2014-11-02

    Nov 2, 2014 ... Hoyle state also, there is discrepancy between various model predictions [18]; whereas. FMD predicts a compact triangle shape and LEFT predicts a bent arm chain structure,. BEC model predicts the Hoyle state to be spherically symmetric. Moreover, the r.m.s. radii of the Hoyle state, predicted by the above ...

  19. Solid state radiation dosimetry

    International Nuclear Information System (INIS)

    Moran, P.R.

    1976-01-01

    Important recent developments provide accurate, sensitive, and reliable radiation measurements by using solid state radiation dosimetry methods. A review of the basic phenomena, devices, practical limitations, and categories of solid state methods is presented. The primary focus is upon the general physics underlying radiation measurements with solid state devices

  20. Physicochemical characterization of pigments and supports in mural paints: Mayapan, Yucatan case; Caracterizacion fisicoquimica de pigmentos y soportes en pinturas murales: caso Mayapan, Yucatan

    Energy Technology Data Exchange (ETDEWEB)

    Silva V, Y. [FIME-UANL, Pedro A. del Alba s/n, Ciudad Universitaria, San Nicolas de los Garza, Nuevo Leon (Mexico); Peraza L, C.A. [Centro INAH Yucatan (Mexico); Bautista M, J.P. [DRPMZA/INAH. Direccion de Registro Publico de Monumentos y Zonas Arqueologicas, Victoria 110, Copilco El Bajo, 04340 Mexico D.F. (Mexico); Arenas A, J. [IFUNAM, Circuito de la Investigacion Cientifica s/n, Ciudad Universitaria, 04510 Mexico D.F. (Mexico)

    2006-07-01

    The present work is focused in the study of pigments and supports located in mural paintings belonging to the archaeological site of Mayapan. The raw materials utilized by the pre hispanic are revealed by means of the use of different techniques of characterization such as Scanning and Transmission Electron Microscopy (SEM and TEM, respectively), Energy Dispersive X-Ray Spectroscopy (EDS), X-Ray Diffraction and Fourier Transform Infrared Spectroscopy (FTIR). The pigments analyzed cover the following colors: yellow, blue, white, orange, black, red, olive and aqua green. In general, the elements O, Ca and C were the main elements present, as well as quantities of Si and Fe were very significant in all the cases. The manufacture techniques for the production of pigments and supports coincided with all those reported in literature for the Maya culture; however, influence from the Central Altiplane could be appreciated. The results obtained by XRD show the phases of calcite (CaCO{sub 3}) and dolomite ferroan (Ca(Mg,Fe)(CO{sub 3}){sub 2}) in all the support. The analyses by FTIR indicated the presence of some agglutinating, but it has not been identified yet. (Author)

  1. Matrix product state description of Halperin states

    Science.gov (United States)

    Crépel, V.; Estienne, B.; Bernevig, B. A.; Lecheminant, P.; Regnault, N.

    2018-04-01

    Many fractional quantum Hall states can be expressed as a correlator of a given conformal field theory used to describe their edge physics. As a consequence, these states admit an economical representation as an exact matrix product state (MPS) that was extensively studied for the systems without any spin or any other internal degrees of freedom. In that case, the correlators are built from a single electronic operator, which is primary with respect to the underlying conformal field theory. We generalize this construction to the archetype of Abelian multicomponent fractional quantum Hall wave functions, the Halperin states. These can be written as conformal blocks involving multiple electronic operators and we explicitly derive their exact MPS representation. In particular, we deal with the caveat of the full wave-function symmetry and show that any additional SU(2) symmetry is preserved by the natural MPS truncation scheme provided by the conformal dimension. We use our method to characterize the topological order of the Halperin states by extracting the topological entanglement entropy. We also evaluate their bulk correlation lengths, which are compared to plasma analogy arguments.

  2. Remote state preparation through hyperentangled atomic states

    Science.gov (United States)

    Nawaz, Mehwish; ul-Islam, Rameez-; Ikram, Manzoor

    2018-04-01

    Hyperentangled states have enhanced channel capacity in quantum processing and have yielded` evident increased communication speed in quantum informatics as a consequence of excessively high information content coded over each quantum entity. In the present article, we intend to demonstrate this fact by utilizing atomic states simultaneously entangled both in internal as well as external degrees of freedom, i.e. the de Broglie motion for remote state preparation (RSP). The results clearly demonstrate that we can efficiently communicate two bit information while manipulating only a single quantum subsystem. The states are prepared and manipulated using atomic Bragg diffraction as well as Ramsey interferometry, both of which are now considered as standard, state of the art tools based on cavity quantum electrodynamics. Since atomic Bragg diffraction is a large interaction time regime and produces spatially well separated, decoherence resistant outputs, the schematics presented here for the RSP offer important perspectives on efficient detection as well as unambiguous information coding and readout. The article summarizes the experimental feasibility of the proposal, culminating with a brief discussion.

  3. Quantum states of light

    CERN Document Server

    Furusawa, Akira

    2015-01-01

    This book explains what quantum states of light look like. Of special interest, a single photon state is explained by using a wave picture, showing that it corresponds to the complementarity of a quantum. Also explained is how light waves are created by photons, again corresponding to the complementarity of a quantum. The author shows how an optical wave is created by superposition of a "vacuum" and a single photon as a typical example. Moreover, squeezed states of light are explained as "longitudinal" waves of light and Schrödinger's cat states as macroscopic superposition states.

  4. Generalized hypergeometric coherent states

    International Nuclear Information System (INIS)

    Appl, Thomas; Schiller, Diethard H

    2004-01-01

    We introduce a large class of holomorphic quantum states by choosing their normalization functions to be given by generalized hypergeometric functions. We call them generalized hypergeometric states in general, and generalized hypergeometric coherent states in particular, if they allow a resolution of unity. Depending on the domain of convergence of the generalized hypergeometric functions, we distinguish generalized hypergeometric states on the plane, the open unit disc and the unit circle. All states are eigenstates of suitably defined lowering operators. We then study their photon number statistics and phase properties as revealed by the Husimi and Pegg-Barnett phase distributions. On the basis of the generalized hypergeometric coherent states we introduce new analytic representations of arbitrary quantum states in Bargmann and Hardy spaces as well as generalized hypergeometric Husimi distributions and corresponding phase distributions

  5. Qutrit magic state distillation

    International Nuclear Information System (INIS)

    Anwar, Hussain; Browne, Dan E; Campbell, Earl T

    2012-01-01

    Magic state distillation (MSD) is a purification protocol that plays an important role in fault-tolerant quantum computation. Repeated iteration of the steps of an MSD protocol generates pure single non-stabilizer states, or magic states, from multiple copies of a mixed resource state using stabilizer operations only. Thus mixed resource states promote the stabilizer operations to full universality. MSD was introduced for qubit-based quantum computation, but little has been known concerning MSD in higher-dimensional qudit-based computation. Here, we describe a general approach for studying MSD in higher dimensions. We use it to investigate the features of a qutrit MSD protocol based on the five-qutrit stabilizer code. We show that this protocol distils non-stabilizer magic states, and identify two types of states that are attractors of this iteration map. Finally, we show how these states may be converted, via stabilizer circuits alone, into a state suitable for state-injected implementation of a non-Clifford phase gate, enabling non-Clifford unitary computation. (paper)

  6. State Technologies Advancement Collaborative

    Energy Technology Data Exchange (ETDEWEB)

    David S. Terry

    2012-01-30

    The U. S. Department of Energy (DOE), National Association of State Energy Officials (NASEO), and Association of State Energy Research and Technology Transfer Institutions (ASERTTI) signed an intergovernmental agreement on November 14, 2002, that allowed states and territories and the Federal Government to better collaborate on energy research, development, demonstration and deployment (RDD&D) projects. The agreement established the State Technologies Advancement Collaborative (STAC) which allowed the states and DOE to move RDD&D forward using an innovative competitive project selection and funding process. A cooperative agreement between DOE and NASEO served as the contracting instrument for this innovative federal-state partnership obligating funds from DOE's Office of Energy Efficiency and Renewable Energy and Office of Fossil Energy to plan, fund, and implement RDD&D projects that were consistent with the common priorities of the states and DOE. DOE's Golden Field Office provided Federal oversight and guidance for the STAC cooperative agreement. The STAC program was built on the foundation of prior Federal-State efforts to collaborate on and engage in joint planning for RDD&D. Although STAC builds on existing, successful programs, it is important to note that it was not intended to replace other successful joint DOE/State initiatives such as the State Energy Program or EERE Special Projects. Overall the STAC process was used to fund, through three competitive solicitations, 35 successful multi-state research, development, deployment, and demonstration projects with an overall average non-federal cost share of 43%. Twenty-two states were awarded at least one prime contract, and organizations in all 50 states and some territories were involved as subcontractors in at least one STAC project. Projects were funded in seven program areas: (1) Building Technologies, (2) Industrial Technologies, (3) Transportation Technologies, (4) Distributed Energy

  7. Quantum State Engineering Via Coherent-State Superpositions

    Science.gov (United States)

    Janszky, Jozsef; Adam, P.; Szabo, S.; Domokos, P.

    1996-01-01

    The quantum interference between the two parts of the optical Schrodinger-cat state makes possible to construct a wide class of quantum states via discrete superpositions of coherent states. Even a small number of coherent states can approximate the given quantum states at a high accuracy when the distance between the coherent states is optimized, e. g. nearly perfect Fock state can be constructed by discrete superpositions of n + 1 coherent states lying in the vicinity of the vacuum state.

  8. Quantum State Smoothing.

    Science.gov (United States)

    Guevara, Ivonne; Wiseman, Howard

    2015-10-30

    Smoothing is an estimation method whereby a classical state (probability distribution for classical variables) at a given time is conditioned on all-time (both earlier and later) observations. Here we define a smoothed quantum state for a partially monitored open quantum system, conditioned on an all-time monitoring-derived record. We calculate the smoothed distribution for a hypothetical unobserved record which, when added to the real record, would complete the monitoring, yielding a pure-state "quantum trajectory." Averaging the pure state over this smoothed distribution yields the (mixed) smoothed quantum state. We study how the choice of actual unraveling affects the purity increase over that of the conventional (filtered) state conditioned only on the past record.

  9. State summaries: Indiana

    Science.gov (United States)

    Shaffer, K.R.

    2006-01-01

    In 2005, the Indiana industrial minerals industry generated $789 million, a record high for the state and an increase of 2.2% from 2004. Among all states, Indiana ranked 24th. Mineral commodities produced in the state included crushed limestone and dolomite, construction sand and gravel, industrial sand, dimension limestone, dimension sandstone, gypsum, common clay and shale, freshwater pearls, peat, lime, and masonry and portland cement.

  10. Muonium states in semiconductors

    International Nuclear Information System (INIS)

    Patterson, B.D.

    1987-01-01

    There is a brief summary of what is known about the muonium states isotropic, anisotropic and diamagnetic in diamond and zincblende semiconductors. The report deals with muonium spectroscopy, including the formation probabilities, hyperfine parameters and electronic g-factors of the states. The dynamics of the states is treated including a discussion of the transition from isotropic Mu to anisotropic Mu in diamond, temperature-dependent linewidthes in silicon and germanium and effects of daping and radiation damage

  11. Planktonic Cyanobacteria of the tropical karstic lake Lagartos from the Yucatan Peninsula, Mexico Las cianobacterias planctónicas del lago tropical cárstico Lagartos de la Península de Yucatán, México

    Directory of Open Access Journals (Sweden)

    Francisco Valadez

    2013-06-01

    Full Text Available The tropical karstic lakes on the Mexican Caribbean Sea coast are numerous. However, there is an enormous gap of knowledge about their limnological conditions and micro-algae communities. In the present study, surface water samples were collected monthly from November 2007 to September 2008 to provide taxonomical composition and biovolume of planktonic cyanobacteria of the lake Lagartos from State of Quintana Roo, Mexico. Water temperature, pH, conductivity, salinity, soluble reactive phosphorus (SRP, dissolved inorganic nitrogen (DIN, and soluble reactive silica (SRSi levels were also analyzed. A total of 22 species were identified. Chroococcales and Oscillatoriales dominated the phytoplankton assemblages during the study period. Chroococcus pulcherrimus, Coelosphaerium confertum, Cyanodyction iac, Phormidium pachydermaticum and Planktolyngbya contorta were recorded for the first time in Mexico. A surplus of DIN (mean value of 42.7µM and low concentrations of SRP (mean value of 1.0µM promoted the enhanced growth and bloom formation of cyanobacteria. The mean biovolume was 3.22X10(8µm³/mL, and two biovolume peaks were observed; the first was dominated by Microcystis panniformis in November 2007 (7.40X10(8µm³/mL, and the second was dominated by Oscillatoria princeps in April 2008 (6.55X10(8µm³/mL. Water quality data, nitrates enrichment, and trophic state based on biovolume, indicated that Lagartos is a hyposaline, secondarily phosphorus-limited, and eutrophic lake, where the cyanobacteria flora was composed mainly by non-heterocystous groups.Los lagos cársticos tropicales en la costa del Caribe mexicano son numerosos. Sin embargo, existe un enorme desconocimiento acerca de sus condiciones limnológicas y de las comunidades de microalgas que se desarrollan en ellos. El objetivo del presente estudio fue estudiar las condiciones limnológicas en las que crecen las poblaciones de cianobacterias planctónicas del lago Lagartos, Quintana Roo

  12. Solid state physics

    CERN Document Server

    Burns, Gerald

    2013-01-01

    Solid State Physics, International Edition covers the fundamentals and the advanced concepts of solid state physics. The book is comprised of 18 chapters that tackle a specific aspect of solid state physics. Chapters 1 to 3 discuss the symmetry aspects of crystalline solids, while Chapter 4 covers the application of X-rays in solid state science. Chapter 5 deals with the anisotropic character of crystals. Chapters 6 to 8 talk about the five common types of bonding in solids, while Chapters 9 and 10 cover the free electron theory and band theory. Chapters 11 and 12 discuss the effects of moveme

  13. Theoretical solid state physics

    International Nuclear Information System (INIS)

    Anon.

    1977-01-01

    Research activities at ORNL in theoretical solid state physics are described. Topics covered include: surface studies; particle-solid interactions; electronic and magnetic properties; and lattice dynamics

  14. Excited states 2

    CERN Document Server

    Lim, Edward C

    2013-01-01

    Excited States, Volume 2 is a collection of papers that deals with molecules in the excited states. The book describes the geometries of molecules in the excited electronic states. One paper describes the geometries of a diatomic molecule and of polyatomic molecules; it also discusses the determination of the many excited state geometries of molecules with two, three, or four atoms by techniques similar to diatomic spectroscopy. Another paper introduces an ordered theory related to excitons in pure and mixed molecular crystals. This paper also presents some experimental data such as those invo

  15. Supersymmetric Displaced Number States

    Directory of Open Access Journals (Sweden)

    Fredy R. Zypman

    2015-06-01

    Full Text Available We introduce, generate and study a family of supersymmetric displaced number states (SDNS that can be considered generalized coherent states of the supersymmetric harmonic oscillator. The family is created from the seminal supersymmetric boson-fermion entangling annihilation operator introduced by Aragone and Zypman and later expanded by Kornbluth and Zypman. Using the momentum representation, the states are obtained analytically in compact form as displaced supersymmetric number states. We study their position-momentum uncertainties, and their bunchiness by classifying them according to their Mandel Q-parameter in phase space. We were also able to find closed form analytical representations in the space and number basis.

  16. The Scandinavian Welfare States

    DEFF Research Database (Denmark)

    Siim, Birte

    1987-01-01

    The paper studies the debate about the Scandinavian welfare states from a feminist persepctive, forcusing on the differences between a feminist perspective and the dominant liberal and critical marxist understanding of the welfare state. In particular it focuses on the argument that the Scandinav...

  17. (MNCHW) in Rivers State?

    African Journals Online (AJOL)

    DATONYE ALASIA

    Monitoring the Maternal, Newborn and Child Health Week — Ordinioha B. ... month . Rivers State has 23 Local Government councils that have an average annual budget that. 5 often exceeds one billion Naira . A substantial part of the State and Local Governments annual .... The nutritional status of 210, 300 children aged.

  18. Solid State Division

    International Nuclear Information System (INIS)

    Green, P.H.; Watson, D.M.

    1989-08-01

    This report contains brief discussions on work done in the Solid State Division of Oak Ridge National Laboratory. The topics covered are: Theoretical Solid State Physics; Neutron scattering; Physical properties of materials; The synthesis and characterization of materials; Ion beam and laser processing; and Structure of solids and surfaces

  19. Solid State Division

    Energy Technology Data Exchange (ETDEWEB)

    Green, P.H.; Watson, D.M. (eds.)

    1989-08-01

    This report contains brief discussions on work done in the Solid State Division of Oak Ridge National Laboratory. The topics covered are: Theoretical Solid State Physics; Neutron scattering; Physical properties of materials; The synthesis and characterization of materials; Ion beam and laser processing; and Structure of solids and surfaces. (LSP)

  20. Gender and the State

    DEFF Research Database (Denmark)

    Dahl, Hanne Marlene; Kantola, Johanna

    2005-01-01

    The article argues from a Nordic, feminist and post-structuralist position that feminism state theories need to be developed methodologically.......The article argues from a Nordic, feminist and post-structuralist position that feminism state theories need to be developed methodologically....

  1. The Danish welfare state

    DEFF Research Database (Denmark)

    Larsen, Jørgen Elm; Bengtsson, Tea Torbenfeldt; Frederiksen, Morten

    The Danish Welfare State analyzes a broad range of areas, such as globalization, labor marked, family life, health and social exclusion, the book demonstrates that life in a modern welfare state is changing rapidly, creating both challenges and possibilities for future management....

  2. Globalization and State Soverignty

    Science.gov (United States)

    2003-04-07

    computer technology have given new impetus to economy. Globalized capital is reorganizing business firms and undermining national politics. Globalization ...5 STATE VS NON-STATE ORGANIZATIONS IN GLOBALIZATION PROCESS................. 7 INFORMATION AND COMMUNICATION TECHNOLOGY (ICT...communications, transportation, and computer technology have given new impetus to globalizers . Around the world, globalizing capital is reorganizing

  3. Kurds, states and tribes

    NARCIS (Netherlands)

    Bruinessen, M.M. van

    2002-01-01

    At most times, Kurdish society has existed at the periphery of, and functioned as a buffer between, two or more neighbouring states. From c. 1500 until the First World War, the relevant states were the Ottoman Empire in the west and Safavid, later Qajar Iran in the east (with Russia and the

  4. DUBNA: Member States

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    The political upheaval in what was the Soviet Union was reflected in an Extraordinary Plenipotentiaries Committee of Joint Institute for Nuclear Research (JINR) Member States, held in Dubna, near Moscow, on 10-13 December, with representatives of eleven sovereign republics of the former Soviet State taking part

  5. Chiropractic. New York State.

    Science.gov (United States)

    New York State Education Dept., Albany. Office of the Professions.

    A reference guide to laws, rules, and regulations that govern the chiropractic practice in New York State is presented. After an overview of professional regulation in the state, licensing requirements/procedures for chiropractors are described. Provisions of Title VIII, Articles 130 and 132, of the Education Law are also covered, along with…

  6. Slippery Wenzel State.

    Science.gov (United States)

    Dai, Xianming; Stogin, Birgitt Boschitsch; Yang, Shikuan; Wong, Tak-Sing

    2015-09-22

    Enhancing the mobility of liquid droplets on rough surfaces is of great interest in industry, with applications ranging from condensation heat transfer to water harvesting to the prevention of icing and frosting. The mobility of a liquid droplet on a rough solid surface has long been associated with its wetting state. When liquid drops are sitting on the top of the solid textures and air is trapped underneath, they are in the Cassie state. When the drops impregnate the solid textures, they are in the Wenzel state. While the Cassie state has long been associated with high droplet mobility and the Wenzel state with droplet pinning, our work challenges this existing convention by showing that both Cassie and Wenzel state droplets can be highly mobile on nanotexture-enabled slippery rough surfaces. Our surfaces were developed by engineering hierachical nano- and microscale textures and infusing liquid lubricant into the nanotextures alone to create a highly slippery rough surface. We have shown that droplet mobility can be maintained even after the Cassie-to-Wenzel transition. Moreover, the discovery of the slippery Wenzel state allows us to assess the fundamental limits of the classical and recent Wenzel models at the highest experimental precision to date, which could not be achieved by any other conventional rough surface. Our results show that the classical Wenzel eq (1936) cannot predict the wetting behaviors of highly wetting liquids in the Wenzel state.

  7. The European State

    DEFF Research Database (Denmark)

    Dosenrode, Søren

    2003-01-01

    The article argues that the EU today shares so many common features with a 'state' that it is best analyzed as such.......The article argues that the EU today shares so many common features with a 'state' that it is best analyzed as such....

  8. State alternative route designations

    International Nuclear Information System (INIS)

    1989-07-01

    Pursuant to the Hazardous Materials Transportation Act (HMTA), the Department of Transportation (DOT) has promulgated a comprehensive set of regulations regarding the highway transportation of high-level radioactive materials. These regulations, under HM-164 and HM-164A, establish interstate highways as the preferred routes for the transportation of radioactive materials within and through the states. The regulations also provide a methodology by which a state may select alternative routes. First,the state must establish a ''state routing agency,'' defined as an entity authorized to use the state legal process to impose routing requirements on carriers of radioactive material (49 CFR 171.8). Once identified, the state routing agency must select routes in accordance with Large Quantity Shipments of Radioactive Materials or an equivalent routing analysis. Adjoining states and localities should be consulted on the impact of proposed alternative routes as a prerequisite of final route selection. Lastly, the states must provide written notice of DOT of any alternative route designation before the routes are deemed effective

  9. States in Process Calculi

    Directory of Open Access Journals (Sweden)

    Christoph Wagner

    2014-08-01

    Full Text Available Formal reasoning about distributed algorithms (like Consensus typically requires to analyze global states in a traditional state-based style. This is in contrast to the traditional action-based reasoning of process calculi. Nevertheless, we use domain-specific variants of the latter, as they are convenient modeling languages in which the local code of processes can be programmed explicitly, with the local state information usually managed via parameter lists of process constants. However, domain-specific process calculi are often equipped with (unlabeled reduction semantics, building upon a rich and convenient notion of structural congruence. Unfortunately, the price for this convenience is that the analysis is cumbersome: the set of reachable states is modulo structural congruence, and the processes' state information is very hard to identify. We extract from congruence classes of reachable states individual state-informative representatives that we supply with a proper formal semantics. As a result, we can now freely switch between the process calculus terms and their representatives, and we can use the stateful representatives to perform assertional reasoning on process calculus models.

  10. Dissociative State and Competence

    Directory of Open Access Journals (Sweden)

    Yu-Ju Lin

    2007-10-01

    Full Text Available This report presents the results of forensic evaluation of the civil competence of a case of alleged dissociative identity disorder (DID and discusses whether such dissociative states substantially jeopardize civil competence. A 40-year-old woman claimed that she had had many personalities since her college days. From the age of 37 to 40, she shopped excessively, which left her with millions of dollars of debt. She ascribed her shopping to a certain identity state, over which she had no control. (In this article, we use the term identity state to replace personality as an objective description of a mental state. She thus raised the petition of civil incompetence. During the forensic evaluation, it was found that the identity states were relatively stable and mutually aware of each other. The switch into another identity state was sometimes under voluntary control. The subject showed consistency and continuity in behavioral patterns across the different identity states, and no matter which identity state she was in, there was no evidence of impairment in her factual knowledge of social situations and her capacity for managing personal affairs. We hence concluded that she was civilly competent despite the claimed DID. Considering that the existence and diagnosis of DID are still under dispute and a diagnosis of DID alone is not sufficient to interdict a person's civil right, important clinical and forensic issues remain to be answered.

  11. Welfare State Transformation

    DEFF Research Database (Denmark)

    Obinger, Herbert; Starke, Peter

    2014-01-01

    This paper describes welfare state transformation in OECD countries since the 1970s against the background of the post-war settlement. Relying on quantitative macro-data and qualitative information from the literature, we show that welfare states have con-verged, especially regarding various...... spending measures, and also to a certain extent in some qualitative policy-making patterns. What has emerged can best be described as the ‘supply-side welfare state’ model, and this overall orientation is reflected in many wel-fare state areas. We differ from earlier prognoses of a race to the bottom...... by generous welfare states and disagree with the view that a supply-side orientation equals ‘lean government’ in terms of social expenditure. But convergence implies that the space to maneuver has shrunk for policy-makers. The consequences of the 2008 financial crisis for welfare states are difficult...

  12. Europeanization and Transnational States

    DEFF Research Database (Denmark)

    Pedersen, Ove Kaj; Jacobsson, Bengt; Lægreid, Per

    This work investigates what happens to an organized political unit when it becomes part of a larger entity and, in particular, how increased European integration and the tentative moves towards a transnational state will affect the European Union's nation state. Europeanization and the transforma...... in central government agencies. It concludes that the consequences of Europeanization can be described as the growth of a transnational administration where identities as well as loyalties are created in processes that transcend the borders of states.......This work investigates what happens to an organized political unit when it becomes part of a larger entity and, in particular, how increased European integration and the tentative moves towards a transnational state will affect the European Union's nation state. Europeanization...... and the transformation of states provides an extensive comparative survey of the central governments in four Scandinavian countries and analyses the ways in which the European Union has influenced the day-to-day work of their state administrations. It includes coverage of: Denmark, a long-standing member of the European...

  13. Europeanization and transnational states

    DEFF Research Database (Denmark)

    Jacobsson, Bengt; Lægreid, Per; Pedersen, Ove K.

    This work investigates what happens to an organized political unit when it becomes part of a larger entity and, in particular, how increased European integration and the tentative moves towards a transnational state will affect the European Union's nation state. Europeanization and the transforma...... in central government agencies. It concludes that the consequences of Europeanization can be described as the growth of a transnational administration where identities as well as loyalties are created in processes that transcend the borders of states.......This work investigates what happens to an organized political unit when it becomes part of a larger entity and, in particular, how increased European integration and the tentative moves towards a transnational state will affect the European Union's nation state. Europeanization...... and the transformation of states provides an extensive comparative survey of the central governments in four Scandinavian countries and analyses the ways in which the European Union has influenced the day-to-day work of their state administrations. It includes coverage of: Denmark, a long-standing member of the European...

  14. Variational Transition State Theory

    Energy Technology Data Exchange (ETDEWEB)

    Truhlar, Donald G. [Univ. of Minnesota, Minneapolis, MN (United States)

    2016-09-29

    This is the final report on a project involving the development and applications of variational transition state theory. This project involved the development of variational transition state theory for gas-phase reactions, including optimized multidimensional tunneling contributions and the application of this theory to gas-phase reactions with a special emphasis on developing reaction rate theory in directions that are important for applications to combustion. The development of variational transition state theory with optimized multidimensional tunneling as a useful computational tool for combustion kinetics involved eight objectives.

  15. The solid state maser

    CERN Document Server

    Orton, J W; Walling, J C; Ter Haar, D

    1970-01-01

    The Solid State Maser presents readings related to solid state maser amplifier from the first tentative theoretical proposals that appeared in the early 1950s to the successful realization of practical devices and their application to satellite communications and radio astronomy almost exactly 10 years later. The book discusses a historical account of the early developments (including that of the ammonia maser) of solid state maser; the properties of paramagnetic ions in crystals; the development of practical low noise amplifiers; and the characteristics of maser devices designed for communica

  16. Autonomy of State Agencies

    DEFF Research Database (Denmark)

    Hansen, Morten Balle; Niklasson, Birgitta; Roness, Paul

    NPM-doctrines states that ideal-type agencies should have a high level of managerial autonomy, while being controlled through result-based control instruments, like performance contracts. In this article, the authors present a first preliminary attempt to comparatively analyze the autonomy of state...... agencies in four Nordic countries: Denmark, Finland, Norway and Sweden. By using survey data from more than 500 state agencies in the four countries, the article analyses whether there is indeed a Scandinavian style of autonomy and result control and assesses which structural, cultural, and environmental...

  17. Varieties in State Capitalism

    DEFF Research Database (Denmark)

    Li, Ming Hua; Cui, Lin; Lu, Jiangyong

    2014-01-01

    Institutional diversity characterizing state-owned enterprises (SOEs) from emerging economies holds critical but under-examined implications for their internationalization activities. Different types of SOEs can exhibit distinct motivations, strategic resources, and adaptive capabilities for pene......Institutional diversity characterizing state-owned enterprises (SOEs) from emerging economies holds critical but under-examined implications for their internationalization activities. Different types of SOEs can exhibit distinct motivations, strategic resources, and adaptive capabilities...... preferences. Recognition of SOEs’ organizational diversity holds important implications for theories on state-owned multinationals....

  18. Theoretical solid state physics

    CERN Document Server

    Haug, Albert

    2013-01-01

    Theoretical Solid State Physics, Volume 1 focuses on the study of solid state physics. The volume first takes a look at the basic concepts and structures of solid state physics, including potential energies of solids, concept and classification of solids, and crystal structure. The book then explains single-electron approximation wherein the methods for calculating energy bands; electron in the field of crystal atoms; laws of motion of the electrons in solids; and electron statistics are discussed. The text describes general forms of solutions and relationships, including collective electron i

  19. Correlations in Werner States

    International Nuclear Information System (INIS)

    Luo Shunlong; Li Nan

    2008-01-01

    Werner states are paradigmatic examples of quantum states and play an innovative role in quantum information theory. In investigating the correlating capability of Werner states, we find the curious phenomenon that quantum correlations, as quantified by the entanglement of formation, may exceed the total correlations, as measured by the quantum mutual information. Consequently, though the entanglement of formation is so widely used in quantifying entanglement, it cannot be interpreted as a consistent measure of quantum correlations per se if we accept the folklore that total correlations are measured (or rather upper bounded) by the quantum mutual information.

  20. Excited states 4

    CERN Document Server

    Lim, Edward C

    2013-01-01

    Excited States, Volume 4 is a collection of papers that deals with the excited states of molecular activity. One paper investigates the resonance Raman spectroscopy as the key to vibrational-electronic coupling. This paper reviews the basic theory of Raman scattering; it also explains the derivation of the Raman spectra, excitation profiles, and depolarization ratios for simple resonance systems. Another paper reviews the magnetic properties of triplet states, including the zero-field resonance techniques, the high-field experiments, and the spin Hamiltonian. This paper focuses on the magnetic

  1. Understanding solid state physics

    CERN Document Server

    Holgate, Sharon Ann

    2009-01-01

    Where Sharon Ann Holgate has succeeded in this book is in packing it with examples of the application of solid state physics to technology. … All the basic elements of solid state physics are covered … . The range of materials is good, including as it does polymers and glasses as well as crystalline solids. In general, the style makes for easy reading. … Overall this book succeeds in showing the relevance of solid state physics to the modern world … .-Contemporary Physics, Vol. 52, No. 2, 2011I was indeed amused and inspired by the wonderful images throughout the book, carefully selected by th

  2. The State and Corporatism

    DEFF Research Database (Denmark)

    Kaspersen, Lars Bo; Schmidt-Hansen, Ulrich

    In the literature on the establishment and development of the Danish variant of corporatism, emphasis has most often been on the role of the social partners. Scholars rarely stress the crucial role which the state has played in the development of the system. We argue that several actors contributed......, we examine the role of the state in the corporatist system during the 1990s in the labour market and within immigration integration policy. We conclude that due to its autonomous power, the state is still a key player in the corporatist system....

  3. Giant resonances on excited states

    International Nuclear Information System (INIS)

    Besold, W.; Reinhard, P.G.; Toepffer, C.

    1984-01-01

    We derive modified RPA equations for small vibrations about excited states. The temperature dependence of collective excitations is examined. The formalism is applied to the ground state and the first excited state of 90 Zr in order to confirm a hypothesis which states that not only the ground state but every excited state of a nucleus has a giant resonance built upon it. (orig.)

  4. 78 FR 4439 - United States

    Science.gov (United States)

    2013-01-22

    ... DEPARTMENT OF JUSTICE Antitrust Division United States v. Oklahoma State Chiropractic Independent... States District Court for the Northern District of Oklahoma in United States of America v. Oklahoma State... January 10, 2013, the United States filed a Complaint alleging that the Defendants and other competing...

  5. State-set branching

    DEFF Research Database (Denmark)

    Jensen, Rune Møller; Veloso, Manuela M.; Bryant, Randal E.

    2008-01-01

    In this article, we present a framework called state-set branching that combines symbolic search based on reduced ordered Binary Decision Diagrams (BDDs) with best-first search, such as A* and greedy best-first search. The framework relies on an extension of these algorithms from expanding a single...... state in each iteration to expanding a set of states. We prove that it is generally sound and optimal for two A* implementations and show how a new BDD technique called branching partitioning can be used to efficiently expand sets of states. The framework is general. It applies to any heuristic function...... framework. The algorithms outperform the ordinary A* algorithm in almost all domains. In addition, they can improve the complexity of A* exponentially and often dominate both A* and blind BDD-based search by several orders of magnitude. Moreover, they have substantially better performance than BDDA...

  6. Solid State Grid Modulator

    National Research Council Canada - National Science Library

    Jones, Franklin

    2001-01-01

    This program was for the design, construction and test of two Solid State Grid Modulators to provide enhanced performance and improved reliability in existing S-band radar transmitters at the Rome Research Site...

  7. Healthcare Associated Infections - State

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Healthcare-Associated Infections (HAI) measures - state data. These measures are developed by Centers for Disease Control and Prevention (CDC) and collected...

  8. Engaging Future Failing States

    Science.gov (United States)

    2011-03-23

    military missions in the Middle East, the Balkans, Africa, Asia , and South America. There is an increasing proliferation of failed and failing states...disparity, overpopulation , food security, health services availability, migration pressures, environmental degradation, personal and 22 community

  9. MSIS State Summary Datamarts

    Data.gov (United States)

    U.S. Department of Health & Human Services — This page provides background needed to take advantage of the capabilities of the MSIS State Summary Datamart. This mart allows the user to develop high-level...

  10. Asking for more State

    DEFF Research Database (Denmark)

    Johansen, Mette-Louise

    2010-01-01

    This paper addresses a period of embedding, as Achille Mbembe puts it when discussing the novelty of the postcolony (Mbembe 2001: 242, 01/09/2008); in this paper the term applies to conceptualise particular social processes of state/citizen entanglement within the realm of western welfare...... of immigrant communities – as experience and structure – only relates to certain domains within the socioeconomic sphere of the modern state. Other domains, such as the bureaucratic welfare services or the juridico-legal structures position immigrants ghettos at the very centre of the state, by which...... the concept of welfare, moral order and legality is constantly negotiated and reconstituted. From this perspective, I explore everyday ghetto life as frontier practices within the community and with the state....

  11. State DOT mission evolution.

    Science.gov (United States)

    2013-04-01

    This paper highlights the challenges faced by six state departments of transportation (California, Colorado, Florida, Massachusetts, Missouri, Oregon) and the views of their respective chief executive officers within the context of national trends. E...

  12. New Mexico State Parks

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This dataset provides an initial version of the generalized physical boundaries of New Mexico State Parks, in polygonal form with limited attributes, compiled using...

  13. Outpatient Imaging Efficiency - State

    Data.gov (United States)

    U.S. Department of Health & Human Services — Use of medical imaging - state data. These measures give you information about hospitals' use of medical imaging tests for outpatients. Examples of medical imaging...

  14. Thermodynamics of Crystalline States

    CERN Document Server

    Fujimoto, Minoru

    2010-01-01

    Thermodynamics is a well-established discipline of physics for properties of matter in thermal equilibrium surroundings. Applying to crystals, however, the laws encounter undefined properties of crystal lattices, which therefore need to be determined for a clear and well-defined description of crystalline states. Thermodynamics of Crystalline States explores the roles played by order variables and dynamic lattices in crystals in a wholly new way. This book is divided into three parts. The book begins by clarifying basic concepts for stable crystals. Next, binary phase transitions are discussed to study collective motion of order variables, as described mostly as classical phenomena. In the third part, the multi-electron system is discussed theoretically, as a quantum-mechanical example, for the superconducting state in metallic crystals. Throughout the book, the role played by the lattice is emphasized and examined in-depth. Thermodynamics of Crystalline States is an introductory treatise and textbook on meso...

  15. State of Services Report

    Data.gov (United States)

    Social Security Administration — A comprehensive monthly report portraying customer experience with our various service options. The State of Services is shared with the ACOSS and is presented to...

  16. Periodically modulated dark states

    Science.gov (United States)

    Han, Yingying; Zhang, Jun; Zhang, Wenxian

    2018-04-01

    Phenomena of electromagnetically induced transparency (PEIT) may be interpreted by the Autler-Townes Splitting (ATS), where the coupled states are split by the coupling laser field, or by the quantum destructive interference (QDI), where the atomic phases caused by the coupling laser and the probe laser field cancel. We propose modulated experiments to explore the PEIT in an alternative way by periodically modulating the coupling and the probe fields in a Λ-type three-level system initially in a dark state. Our analytical and numerical results rule out the ATS interpretation and show that the QDI interpretation is more appropriate for the modulated experiments. Interestingly, dark state persists in the double-modulation situation where control and probe fields never occur simultaneously, which is significant difference from the traditional dark state condition. The proposed experiments are readily implemented in atomic gases, artificial atoms in superconducting quantum devices, or three-level meta-atoms in meta-materials.

  17. State Climatology Books

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Substation history publications by state. Includes station metadata such as station name and location changes, observer names and changes, alternate station names....

  18. Baryoniums and related states

    International Nuclear Information System (INIS)

    Hong-Mo, C.

    1978-01-01

    A brief introduction is given to current theoretical ideas on baryonium states with particular emphasis on their interpretation as 'colour molecules'. It is argued that baryonium spectroscopy provides a valuable test for colour as a new degree of freedom. (author)

  19. US State Submerged Lands

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — The Submerged Lands Act (43 U.S.C. Section 1301 et seq.) grants coastal states title to natural resources located within their coastal submerged lands and navigable...

  20. State Capitol Buildings

    Data.gov (United States)

    Department of Homeland Security — This shapefile will display the locations of the fifty state capitol buildings as well as the territorial capitol buildings for the US Virgin Islands, Guam, Northern...

  1. United States housing, 2012

    Science.gov (United States)

    Delton Alderman

    2013-01-01

    Provides current and historical information on housing market in the United States. Information includes trends for housing permits and starts, housing completions for single and multifamily units, and sales and construction. This report will be updated annually.

  2. State Agency Administrative Boundaries

    Data.gov (United States)

    Kansas Data Access and Support Center — This database comprises 28 State agency boundaries and point of contact. The Kansas Geological Survey collected legal descriptions of the boundaries for various...

  3. State Geodatabase for Indiana

    Data.gov (United States)

    US Census Bureau, Department of Commerce — The 2015 TIGER Geodatabases are extracts of selected nation based and state based geographic and cartographic information from the U.S. Census Bureau's Master...

  4. Political State Boundary (National)

    Data.gov (United States)

    Department of Transportation — State boundaries with political limit - boundaries extending into the ocean (NTAD). The TIGER/Line Files are shapefiles and related database files (.dbf) that are an...

  5. State Geodatabase for Connecticut

    Data.gov (United States)

    US Census Bureau, Department of Commerce — The 2015 TIGER Geodatabases are extracts of selected nation based and state based geographic and cartographic information from the U.S. Census Bureau's Master...

  6. Healthcare Associated Infections - State

    Data.gov (United States)

    U.S. Department of Health & Human Services — The Healthcare-Associated Infections (HAI) measures - state data. These measures are developed by Centers for Disease Control and Prevention (CDC) and collected...

  7. Asociación entre la incidencia de leishmaniosis cutánea y el índice de desarrollo humano y sus componentes en cuatro estados endémicos de Venezuela Association between cutaneous leishmaniasis incidence and the human development index and its components in four endemic states of Venezuela

    Directory of Open Access Journals (Sweden)

    Alfonso J. Rodríguez-Morales

    2010-03-01

    the linear regression models, it was observed that the relationship between epidemiological and social variables was different at States levels. For Mérida and Trujillo it was observed a significant decrease in the CL regard to the increase of literacy (p<0.05, of the gross combined enrollment (p<0.05, life expectancy (p<0.05, money income (p<0.05 and the HDI (p<0.05. Conclusion. This information reflects the significant influence of socioeconomical indicators on the CL incidence at Trujillo and Merida, being an inverse relationship between both types of variables; with an increase or improvement in the socioeconomical indicators, the disease incidence rate decreased.

  8. Appealing to the State

    DEFF Research Database (Denmark)

    Nielsen, Marie Vejrup

    2014-01-01

    This essay analyzes identity formation of majority religion in the context of intentional, political processes of change in state-church relations from a perspective that combines discursive institutionalism with the insights from governance research.......This essay analyzes identity formation of majority religion in the context of intentional, political processes of change in state-church relations from a perspective that combines discursive institutionalism with the insights from governance research....

  9. State responses to biotechnology.

    Science.gov (United States)

    Harris, Rebecca C

    2015-01-01

    This article reviews biotechnology legislation in the 50 states for 11 policy areas spanning 1990-2010, an era of immense growth in biotechnology, genetic knowledge, and significant policy development. Policies regarding health insurance, life insurance, long-term care insurance, DNA data bank collection, biotech research protection, biotech promotion and support, employment discrimination, genetic counselor licensing, human cloning, and genetic privacy each represent major policy responses arising from biotechnology and coinciding with key areas of state regulation (insurance, criminal justice, economic development, labor law, health and safety, privacy, and property rights). This analysis seeks to answer three questions regarding biotechnology legislation at the state level: who is acting (policy adoption), when is policy adopted (policy timing), and what is policy doing (policy content). Theoretical concerns examine state ideology (conservative or liberal), policy type (economic or moral), and the role of external events (federal law, news events, etc.) on state policy adoption. Findings suggest ideological patterns in adoption, timing, and content of biotech policy. Findings also suggest economic policies tend to be more uniform in content than moral policies, and findings also document a clear link between federal policy development, external events, and state policy response.

  10. Permutationally invariant state reconstruction

    DEFF Research Database (Denmark)

    Moroder, Tobias; Hyllus, Philipp; Tóth, Géza

    2012-01-01

    Feasible tomography schemes for large particle numbers must possess, besides an appropriate data acquisition protocol, an efficient way to reconstruct the density operator from the observed finite data set. Since state reconstruction typically requires the solution of a nonlinear large-scale opti......Feasible tomography schemes for large particle numbers must possess, besides an appropriate data acquisition protocol, an efficient way to reconstruct the density operator from the observed finite data set. Since state reconstruction typically requires the solution of a nonlinear large......-scale optimization problem, this is a major challenge in the design of scalable tomography schemes. Here we present an efficient state reconstruction scheme for permutationally invariant quantum state tomography. It works for all common state-of-the-art reconstruction principles, including, in particular, maximum...... likelihood and least squares methods, which are the preferred choices in today's experiments. This high efficiency is achieved by greatly reducing the dimensionality of the problem employing a particular representation of permutationally invariant states known from spin coupling combined with convex...

  11. Born Level Bound States

    Science.gov (United States)

    Hoyer, Paul

    2017-05-01

    Bound state poles in the S-matrix of perturbative QED are generated by the divergence of the expansion in α . The perturbative corrections are necessarily singular when expanding around free, {O}( α ^0 ) in and out states that have no overlap with finite-sized atomic wave functions. Nevertheless, measurables such as binding energies do have well-behaved expansions in powers of α (and log α ). It is desirable to formulate the concept of "lowest order" for gauge theory bound states such that higher order corrections vanish in the α → 0 limit. This may allow to determine a lowest order term for QCD hadrons which incorporates essential features such as confinement and chiral symmetry breaking, and thus can serve as the starting point of a useful perturbative expansion. I discuss a "Born" (no loop, lowest order in \\hbar ) approximation. Born level states are bound by gauge fields which satisfy the classical field equations. Gauss' law determines a distinct field A^0({\\varvec{x}}) for each instantaneous position of the charges. A Poincaré covariant boundary condition for the gluon field leads to a confining potential for q\\bar{q} and qqq states. In frames where the bound state is in motion the classical gauge field is obtained by a Lorentz boost of the rest frame field.

  12. Machine learning topological states

    Science.gov (United States)

    Deng, Dong-Ling; Li, Xiaopeng; Das Sarma, S.

    2017-11-01

    Artificial neural networks and machine learning have now reached a new era after several decades of improvement where applications are to explode in many fields of science, industry, and technology. Here, we use artificial neural networks to study an intriguing phenomenon in quantum physics—the topological phases of matter. We find that certain topological states, either symmetry-protected or with intrinsic topological order, can be represented with classical artificial neural networks. This is demonstrated by using three concrete spin systems, the one-dimensional (1D) symmetry-protected topological cluster state and the 2D and 3D toric code states with intrinsic topological orders. For all three cases, we show rigorously that the topological ground states can be represented by short-range neural networks in an exact and efficient fashion—the required number of hidden neurons is as small as the number of physical spins and the number of parameters scales only linearly with the system size. For the 2D toric-code model, we find that the proposed short-range neural networks can describe the excited states with Abelian anyons and their nontrivial mutual statistics as well. In addition, by using reinforcement learning we show that neural networks are capable of finding the topological ground states of nonintegrable Hamiltonians with strong interactions and studying their topological phase transitions. Our results demonstrate explicitly the exceptional power of neural networks in describing topological quantum states, and at the same time provide valuable guidance to machine learning of topological phases in generic lattice models.

  13. Intranets and Extranets at State Libraries in the United States.

    Science.gov (United States)

    Bolt, Nancy M.

    This paper is an analysis of Intranets and Extranets at selected state libraries in the United States. The paper does not review World Wide Web sites designed for use by the general public; rather, it focuses on Web sites designed and delivered by the state library to a targeted audience, typically state government employees, state library…

  14. 31 CFR 515.321 - United States; continental United States.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false United States; continental United... General Definitions § 515.321 United States; continental United States. The term United States means the United States and all areas under the jurisdiction or authority thereof, including the Trust Territory of...

  15. 31 CFR 500.321 - United States; continental United States.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false United States; continental United... General Definitions § 500.321 United States; continental United States. The term United States means the United States and all areas under the jurisdiction or authority thereof, including U.S. trust territories...

  16. 31 CFR 535.321 - United States; continental United States.

    Science.gov (United States)

    2010-07-01

    ... 31 Money and Finance: Treasury 3 2010-07-01 2010-07-01 false United States; continental United... General Definitions § 535.321 United States; continental United States. The term United States means the United States and all areas under the jurisdiction or authority thereof including the Trust Territory of...

  17. State Online College Job Market: Ranking the States

    Science.gov (United States)

    Carnevale, Anthony; Jayasundera, Tamara; Repnikov, Dmitri; Gulish, Artem

    2015-01-01

    "State Online College Job Market: Ranking the States" analyzes the online college labor market on a state-by-state basis. We examine the geographic distribution of online job ads for college graduates within industries and occupational clusters, and compare the relative strength of the online college labor market across states. We…

  18. Tectonic model of thrusts and imbricated thrusting wedge on the northwestern flank of the Merida Andes between Torondoy and Valera (Venezuela)

    OpenAIRE

    Castrillo, J.T.; Hervouet, Y.

    1996-01-01

    Ce travail, utilisant l'imagerie satellitaire (Landsat TM), des données de terrain, et la modélisation informatique des structures tectoniques, montre que le flanc nord-ouest des Andes de Mérida est constitué de chevauchements à pendage sud-est et de rétrochevauchements imbriqués à pendage nord-ouest fonctionnant du Miocène au Pléistocène. Les décollements dans la couverture se situent dans le Crétacé supérieur et le Néogène. Le chevauchement du socle sur le bassin de Maracaïbo atteint 35 km ...

  19. Metastability of transient states

    Science.gov (United States)

    Rafailov, Michael K.

    2017-05-01

    High intensity ultrashort pulse causes dramatic perturbations in electronic structure of condensed matter. In the same time energy in high intensity single pulse may not be sufficient to disrupt sample thermal equilibrium. Interesting experimental results in ultrashort pulse photo-excited solids have been reported recently on transient athermal phenomena induced by ultrashort high intensity low energy pulse - phenomena related to both athermal phase transitions and athermal state changes. Athermal non-equilibrium of electronic system - and induced changes in magnetic and optical states, may exist only for a period of time comparable to excited carriers' relaxation time. That time is not sufficient for emerging application ranging from light induced superconductivity to infrared countermeasures. While single pulse interaction with condensed matter leading to transit state appearance is well observed, documented, and, to some extends, explained, one of the major problem is to maintain meta-stability of such transient states. Metastability of athermal non-equilibrium that could last well beyond electronic system relaxation time. The objective of this paper is to discuss some issues and approaches to meta-stability of transient states induced by ultrashort pulses in condensed matter.

  20. The association between state attachment security and state Mindfulness.

    Directory of Open Access Journals (Sweden)

    Christopher A Pepping

    Full Text Available Recent research suggests that attachment and mindfulness are related, though the nature of this association is unclear. Here we present two studies examining whether there is a causal relationship between state attachment and state mindfulness. Study 1 investigated the effects of experimentally increasing state mindfulness on state attachment security. State mindfulness was successfully enhanced, but this led to no change in state attachment security. Study 2 investigated the effects of experimentally enhancing state attachment security on state mindfulness. State attachment security was successfully enhanced, but this did not lead to any change in state mindfulness. These findings suggest that there is not a direct, immediate causal relationship between state attachment and state mindfulness as a result of brief experimental manipulations. Future research should examine these associations in longer term interventions.

  1. Rapanos v. United States & Carabell v. United States

    Science.gov (United States)

    Documents associated with guidance for implementing the definition of waters of the United States under the Clean Water Act following the Rapanos v. United States, and Carabell v. United States Supreme Court decision.

  2. The state manager

    International Nuclear Information System (INIS)

    Defendini, A.; Jones, R.; Matheys, J.P.; Vyvre, P.V.; Vascotto, A.

    1992-01-01

    The State Manager system (SM) is a set of tools, developed at CERN, for the control of large data-acquisition systems. A dedicated object-based language is used to describe the various components of the data-acquisition system. Each component is declared in terms of finite state machines and sequences of parametrized actions to be performed for operations such as the start and end of a run. The description, written by the user, is translated into Ada to produce a run-control program capable of controlling processes in a distributed environment. A Motif-based graphical interface to the control program displays the current state of all the components and can be used to control the overall data-acquisition system. The SM has been used by several experiments both at CERN and other organizations. We present here the architecture of the SM, some design choices, and the experience acquired from its use. (author)

  3. State summaries: Colorado

    Science.gov (United States)

    Keller, J.; Carroll, C.; Widmann, B.

    2006-01-01

    According to the Colorado Geological Survey (CGS), Colorado's mining industry enjoyed a record-breaking year in 2005. For the whole year, the total value of nonfuel minerals, coal and uranium produced in the state in 2005 amounted to $2.4 billion. The production value of $1.52 billion in the nonfuel sector broke the previous record of $1.3 billion set in 1980, and is 60% higher than the revised 2004 CGS estimate of $950.5 million. The United States Geological Survey (USGS) ranked Colorado ninth among the states in nonfuel mineral value, up from 17th in 2004. About $1 billion of the nonfuel total is from metal mining. New record-high productions were achieved not only for molybdenum but also for coal and goal.

  4. State Controled Avantgarde?

    DEFF Research Database (Denmark)

    Kreutzfeldt, Jacob

    2016-01-01

    State controlled radio developed in the Nordic countries by the middle of the 1920es. Danish Radio was established for a trial period in April 1925, and was permanently founded in April 1926. Swedish radio was founded in 1925 and Norwegian radio in 1933. The new and unquestionably powerful medium...... had already given rise to avant-garde imagination in Europe (Kahn 1994), but proved in its state controlled institutionalisation less available for experimentation than hoped. Yet radio remained attractive for contemporary avant-garde oriented artists, but few succeeded in accessing the mechanical...... apparatus of state radio. One example of this is the Danish writer Emil Bønnelyckes collaboration with Danish radio on Vore Dages København i Radiofoniske Billeder (Contemporary Copenhagen in Radiophonic Images) – a 4 and a half hour show broadcast prime time on Sunday evening 7. December 1930. According...

  5. Combining programs and state machines

    NARCIS (Netherlands)

    Bergstra, J.A.; Ponse, A.

    2002-01-01

    State machines consume and process actions complementary to programs issuing actions. State machines maintain a state and reply with a boolean response to each action in their interface. As state machines offer a service to programs, their interface is also called a service interface. State

  6. Resonant state expansions

    International Nuclear Information System (INIS)

    Lind, P.

    1993-02-01

    The completeness properties of the discrete set of bound state, virtual states and resonances characterizing the system of a single nonrelativistic particle moving in a central cutoff potential is investigated. From a completeness relation in terms of these discrete states and complex scattering states one can derive several Resonant State Expansions (RSE). It is interesting to obtain purely discrete expansion which, if valid, would significantly simplify the treatment of the continuum. Such expansions can be derived using Mittag-Leffler (ML) theory for a cutoff potential and it would be nice to see if one can obtain the same expansions starting from an eigenfunction theory that is not restricted to a finite sphere. The RSE of Greens functions is especially important, e.g. in the continuum RPA (CRPA) method of treating giant resonances in nuclear physics. The convergence of RSE is studied in simple cases using square well wavefunctions in order to achieve high numerical accuracy. Several expansions can be derived from each other by using the theory of analytic functions and one can the see how to obtain a natural discretization of the continuum. Since the resonance wavefunctions are oscillating with an exponentially increasing amplitude, and therefore have to be interpreted through some regularization procedure, every statement made about quantities involving such states is checked by numerical calculations.Realistic nuclear wavefunctions, generated by a Wood-Saxon potential, are used to test also the usefulness of RSE in a realistic nuclear calculation. There are some fundamental differences between different symmetries of the integral contour that defines the continuum in RSE. One kind of symmetry is necessary to have an expansion of the unity operator that is idempotent. Another symmetry must be used if we want purely discrete expansions. These are found to be of the same form as given by ML. (29 refs.)

  7. The Association between State Attachment Security and State Mindfulness

    OpenAIRE

    Pepping, Christopher A.; Davis, Penelope J.; O?Donovan, Analise

    2015-01-01

    Recent research suggests that attachment and mindfulness are related, though the nature of this association is unclear. Here we present two studies examining whether there is a causal relationship between state attachment and state mindfulness. Study 1 investigated the effects of experimentally increasing state mindfulness on state attachment security. State mindfulness was successfully enhanced, but this led to no change in state attachment security. Study 2 investigated the effects of exper...

  8. Solid state physics

    CERN Document Server

    Grosso, Giuseppe

    2013-01-01

    Solid State Physics is a textbook for students of physics, material science, chemistry, and engineering. It is the state-of-the-art presentation of the theoretical foundations and application of the quantum structure of matter and materials. This second edition provides timely coverage of the most important scientific breakthroughs of the last decade (especially in low-dimensional systems and quantum transport). It helps build readers' understanding of the newest advances in condensed matter physics with rigorous yet clear mathematics. Examples are an integral part of the text, carefully de

  9. State Dependence in Unemployment

    DEFF Research Database (Denmark)

    Ahmad, Nisar

    2014-01-01

    This study examines the extent state dependence among unemployed immigrants in a dynamic discrete choice framework. Three alternative methodologies are employed to control for the problem of the initial condition. The empirical findings show that there is a considerable correlation between...... the unobserved individual heterogeneity and the initial condition and that the degree of state dependence is overstated if we do not address this problem. The results show that an individual who was unemployed at period “t-1” has 6.5 percentage points higher probability of being unemployed again at period t...

  10. State Housing Revival

    DEFF Research Database (Denmark)

    Donovan, Elizabeth

    2015-01-01

    Government funded housing for people in need is a challenge many countries face around the world. This research investigates how to sustainably regenerate post-war suburban state housing in New Zealand, in particular, the suburb of Glen Innes in Auckland. Reviving the community and regenerating...... affordable housing. Together the conclusions drawn from empirical and ethnographic research, informed a general design toolbox and guidelines. The established guidelines and toolbox were applied at a master plan level and in-depth to an existing state house within the specific neighbourhood in Glen Innes...

  11. Solid-state circuits

    CERN Document Server

    Pridham, G J

    2013-01-01

    Solid-State Circuits provides an introduction to the theory and practice underlying solid-state circuits, laying particular emphasis on field effect transistors and integrated circuits. Topics range from construction and characteristics of semiconductor devices to rectification and power supplies, low-frequency amplifiers, sine- and square-wave oscillators, and high-frequency effects and circuits. Black-box equivalent circuits of bipolar transistors, physical equivalent circuits of bipolar transistors, and equivalent circuits of field effect transistors are also covered. This volume is divided

  12. States of Liberation

    DEFF Research Database (Denmark)

    Sen, Somdeep

    When Hamas won the 2006 Palestinian Legislative Council elections it was a critical juncture in the life of a Palestinian faction that had, over the years, garnered the status of an iconic armed resistance. Was it viable, scholars asked, for the organization to maintain its position of resistance...... the existence of a Palestinian governing authority. This despite being cast in the image of the post-colonial state, with its attendant bureaucratic and state-like coercive practices experienced by Palestinians in their everyday lives. In this way, while many have struggled to explain Hamas’ dual status...

  13. Solid-State Nanopore

    Directory of Open Access Journals (Sweden)

    Zhishan Yuan

    2018-02-01

    Full Text Available Abstract Solid-state nanopore has captured the attention of many researchers due to its characteristic of nanoscale. Now, different fabrication methods have been reported, which can be summarized into two broad categories: “top-down” etching technology and “bottom-up” shrinkage technology. Ion track etching method, mask etching method chemical solution etching method, and high-energy particle etching and shrinkage method are exhibited in this report. Besides, we also discussed applications of solid-state nanopore fabrication technology in DNA sequencing, protein detection, and energy conversion.

  14. Solid state theory

    CERN Document Server

    Harrison, Walter A

    2011-01-01

    ""A well-written text . . . should find a wide readership, especially among graduate students."" - Dr. J. I. Pankove, RCA.The field of solid state theory, including crystallography, semi-conductor physics, and various applications in chemistry and electrical engineering, is highly relevant to many areas of modern science and industry. Professor Harrison's well-known text offers an excellent one-year graduate course in this active and important area of research. While presenting a broad overview of the fundamental concepts and methods of solid state physics, including the basic quantum theory o

  15. Methane and sulfate dynamics in sediments from mangrove-dominated tropical coastal lagoons, Yucatan, Mexico

    Science.gov (United States)

    Chuang, P. C.; Young, Megan B.; Dale, Andrew W.; Miller, Laurence G.; Herrera-Silveira, Jorge A.; Paytan, Adina

    2016-01-01

    Porewater profiles in sediment cores from mangrove-dominated coastal lagoons (Celestún and Chelem) on the Yucatán Peninsula, Mexico, reveal the widespread coexistence of dissolved methane and sulfate. This observation is interesting since dissolved methane in porewaters is typically oxidized anaerobically by sulfate. To explain the observations we used a numerical transport-reaction model that was constrained by the field observations. The model suggests that methane in the upper sediments is produced in the sulfate reduction zone at rates ranging between 0.012 and 31 mmol m−2 d−1, concurrent with sulfate reduction rates between 1.1 and 24 mmol SO42− m−2 d−1. These processes are supported by high organic matter content in the sediment and the use of non-competitive substrates by methanogenic microorganisms. Indeed sediment slurry incubation experiments show that non-competitive substrates such as trimethylamine (TMA) and methanol can be utilized for microbial methanogenesis at the study sites. The model also indicates that a significant fraction of methane is transported to the sulfate reduction zone from deeper zones within the sedimentary column by rising bubbles and gas dissolution. The shallow depths of methane production and the fast rising methane gas bubbles reduce the likelihood for oxidation, thereby allowing a large fraction of the methane formed in the sediments to escape to the overlying water column.

  16. [Infective endocarditis. 5-years experience in a third-level reference center in Yucatan, Mexico].

    Science.gov (United States)

    Vega-Sánchez, Angel Emmanuel; Santaularia-Tomas, Miguel; Pérez-Román, Diana Isabel; Cortés-Telles, Arturo

    2016-01-01

    Infective endocarditis is a disease with high morbidity and mortality. The clinical characteristics differ among populations. Therefore it is important to know the characteristics of the disease in our region. This is an observational study that included all patients diagnosed with infective endocarditis from 1 January 2009 until 31 December 2014. The data are showed as frequencies and percentages altogether with medians with interquartile range. 10 cases were included. The median age was 34 years (IQR 26-41). Several risk factors were identified and included: previous valvular heart disease, patients with chronic kidney disease who have had a vascular access and previous history of immunological disease. The native mitral valve was the most affected. The size of vegetations had a median length of 14 mm (IQR 9.3-16). Streptococcus alpha hemolytic was the most common organism. In-hospital mortality rate was 10 %. The behavior of the disease is similar to other national series. We identify risk factors that could be related to the type of morbidities in the region.

  17. Spatiotemporal variations of live coral cover in the northern Mesoamerican Reef System, Yucatan Peninsula, Mexico

    Directory of Open Access Journals (Sweden)

    Linda M. Barranco

    2016-06-01

    Full Text Available Evaluating the response of coral assemblages to different disturbances is important because variations in species composition may have consequences for ecosystem functioning due to their different functional roles in coral reefs. This study evaluates changes in diversity, structure and composition of coral assemblages of the coral reefs of two national parks in the northern sector of the Mesoamerican Barrier Reef System spanning the period from 2006 to 2012, just after the impact of two hurricanes in the area. Coral assemblages in the Cancún National Park included fewer species and lower live coral coverage ( < 15% than those recorded in Cozumel. In the Cancún National Park, the species with the highest coral cover was Porites astreoides (more than 40% relative cover, and no significant temporal changes were observed in live coral cover and species composition. On the other hand, in the Cozumel National Park the dominant species were Agaricia agaricites, Siderastrea siderea and Porites astreoides, and the coral reefs showed an increase in live coral cover from 16% in 2006 to 29% in 2012. The dynamics of coral assemblages differed between the two parks: while there is an apparent stability in the current composition of the Cancún reefs, the Cozumel reefs show an increase in the abundance of the aforementioned dominant species. However, it is possible that the population characteristics of the species that dominate the coral assemblages in both national parks, such as those of fast population growth and of small colony size, do not entirely fulfill the main function of accretion and habitat heterogeneity, and more research is therefore needed to test this hypothesis.

  18. An Index of Biotic Integrity for shallow streams of the Hondo River basin, Yucatan Peninsula

    International Nuclear Information System (INIS)

    Schmitter-Soto, Juan J.; Ruiz-Cauich, Lissie E.; Herrera, Roberto L.; Gonzalez-Solis, David

    2011-01-01

    An Index of Biotic Integrity (IBI) is proposed, based on the fish communities and populations in streams of the Hondo River basin, Mexico-Belize. Freshwater environments in this area are threatened by exotic fishes, eutrophication, and pesticide pollution, among other problems. This IBI should allow to identify the most vulnerable sites and eventually guide rehabilitation efforts. Data on composition, structure, and function of fish communities were evaluated. Twenty-three sites in the Mexican part of the basin were explored; a stratified sample of 13 sites was used to design the IBI, and the rest were used to test and refine the index. Thirty-four candidate indicator metrics were scanned for their correlation with an index of water and habitat quality (IWHQ), as well as for the possible influence of stream width and altitude or distance to the Hondo River mainstem. Twelve variables were selected to constitute the IBI: relative abundances of Astyanax aeneus, 'Cichlasoma' urophthalmus, Poecilia mexicana, Poecilia sp. (a new species, probably endemic to the upper Hondo River basin), Xiphophorus hellerii, and X. maculatus; relative abundances of bentholimnetic, herbivore, and sensitive species; percentage of native and tolerant species; and Pielou's evenness index. Most of the sites have a low-medium quality and integrity, showing impact due to partial channelization or to suboptimal water quality, reflected in scarcity or absence of sensitive species, frequent excess of tolerant species, occasional presence of exotics, dominance of herbivores (perhaps due to proliferation of filamentous algae), or dominance of the opportunistic species P. mexicana. The streams with better water and habitat quality are those farthest away from the river mainstem, probably because of lower human population and economical production. - Research Highlights: → An Index of Biotic Integrity based on fishes is proposed for streams of the Hondo River basin. → Twelve variables were included, mostly relative abundances of species and ecological guilds. → Most of the sampled sites have a low-medium quality and integrity. → The streams with better water and habitat quality are those farthest away from the river mainstem. [es

  19. Physicochemical characterization of pigments and supports in mural paints: Mayapan, Yucatan case

    International Nuclear Information System (INIS)

    Silva V, Y.; Peraza L, C.A.; Bautista M, J.P.; Arenas A, J.

    2006-01-01

    The present work is focused in the study of pigments and supports located in mural paintings belonging to the archaeological site of Mayapan. The raw materials utilized by the pre hispanic are revealed by means of the use of different techniques of characterization such as Scanning and Transmission Electron Microscopy (SEM and TEM, respectively), Energy Dispersive X-Ray Spectroscopy (EDS), X-Ray Diffraction and Fourier Transform Infrared Spectroscopy (FTIR). The pigments analyzed cover the following colors: yellow, blue, white, orange, black, red, olive and aqua green. In general, the elements O, Ca and C were the main elements present, as well as quantities of Si and Fe were very significant in all the cases. The manufacture techniques for the production of pigments and supports coincided with all those reported in literature for the Maya culture; however, influence from the Central Altiplane could be appreciated. The results obtained by XRD show the phases of calcite (CaCO 3 ) and dolomite ferroan (Ca(Mg,Fe)(CO 3 ) 2 ) in all the support. The analyses by FTIR indicated the presence of some agglutinating, but it has not been identified yet. (Author)

  20. An Index of Biotic Integrity for shallow streams of the Hondo River basin, Yucatan Peninsula

    Energy Technology Data Exchange (ETDEWEB)

    Schmitter-Soto, Juan J., E-mail: jschmitt@ecosur.mx; Ruiz-Cauich, Lissie E.; Herrera, Roberto L.; Gonzalez-Solis, David

    2011-01-15

    An Index of Biotic Integrity (IBI) is proposed, based on the fish communities and populations in streams of the Hondo River basin, Mexico-Belize. Freshwater environments in this area are threatened by exotic fishes, eutrophication, and pesticide pollution, among other problems. This IBI should allow to identify the most vulnerable sites and eventually guide rehabilitation efforts. Data on composition, structure, and function of fish communities were evaluated. Twenty-three sites in the Mexican part of the basin were explored; a stratified sample of 13 sites was used to design the IBI, and the rest were used to test and refine the index. Thirty-four candidate indicator metrics were scanned for their correlation with an index of water and habitat quality (IWHQ), as well as for the possible influence of stream width and altitude or distance to the Hondo River mainstem. Twelve variables were selected to constitute the IBI: relative abundances of Astyanax aeneus, 'Cichlasoma' urophthalmus, Poecilia mexicana, Poecilia sp. (a new species, probably endemic to the upper Hondo River basin), Xiphophorus hellerii, and X. maculatus; relative abundances of bentholimnetic, herbivore, and sensitive species; percentage of native and tolerant species; and Pielou's evenness index. Most of the sites have a low-medium quality and integrity, showing impact due to partial channelization or to suboptimal water quality, reflected in scarcity or absence of sensitive species, frequent excess of tolerant species, occasional presence of exotics, dominance of herbivores (perhaps due to proliferation of filamentous algae), or dominance of the opportunistic species P. mexicana. The streams with better water and habitat quality are those farthest away from the river mainstem, probably because of lower human population and economical production. - Research Highlights: {yields} An Index of Biotic Integrity based on fishes is proposed for streams of the Hondo River basin. {yields} Twelve variables were included, mostly relative abundances of species and ecological guilds. {yields} Most of the sampled sites have a low-medium quality and integrity. {yields} The streams with better water and habitat quality are those farthest away from the river mainstem. [Spanish] RESUMEN: Se propone un Indice Biotico de Integridad (IBI) con base en caracteristicas de las comunidades y poblaciones de peces en arroyos de la cuenca del rio Hondo, Mexico-Belice. Los ambientes dulceacuicolas de esta area estan bajo amenaza por peces exoticos, eutrofizacion y plaguicidas, entre otros problemas. Este IBI debe permitir identificar los sitios mas vulnerables y, eventualmente, guiar los esfuerzos de rehabilitacion. Se evaluaron datos de composicion, estructura y funcion de las comunidades de peces. Se exploraron 23 sitios en la parte mexicana de la cuenca; se uso una submuestra estratificada de 13 sitios para disenar el IBI y el resto para probarlo y refinarlo. Se busco la correlacion de 34 posibles metricos con un indice de calidad del agua y ambiente, asi como con la posible influencia de la anchura del arroyo y la altitud y distancia al cauce principal del rio Hondo. Se seleccionaron doce metricos para constituir el IBI: las abundancias relativas de Astyanax aeneus, 'Cichlasoma' urophthalmus, Poecilia mexicana, Poecilia sp. (una nueva especie, probablemente endemica de la cuenca alta), Xiphophorus hellerii y X. maculatus; las abundancias relativas de especies bentolimneticas, herbivoras y sensibles; el porcentaje de especies nativas y tolerantes; y el indice de equidad de Pielou. La mayoria de los sitios son de calidad e integridad media-baja, con impactos por canalizacion parcial o calidad suboptima del agua, reflejados en escasez o ausencia de especies sensibles, frecuente exceso de especies tolerantes, presencia ocasional de exoticos, dominancia de herbivoros (por proliferacion de algas filamentosas) o dominancia de la especie oportunista P. mexicana. Los arroyos de mejor calidad de agua y habitat son los mas lejanos al cauce principal del rio, probablemente por su menor poblacion humana y produccion economica.

  1. The Influence of Water Access in Subjective Well-Being: Some Evidence in Yucatan, Mexico

    Science.gov (United States)

    Guardiola, Jorge; Gonzalez-Gomez, Francisco; Grajales, Angel Lendechy

    2013-01-01

    The literature on happiness or subjective well-being has explored the determinants of happiness without taking into consideration the role that water plays. In this paper we attempt to draw attention to water in subjective well-being studies. Approximately one hundred million people do not have access to water. A lack of clean water causes…

  2. Fish functional groups in a tropical wetland of the Yucatan Peninsula, Mexico

    Directory of Open Access Journals (Sweden)

    Fernando Córdova-Tapia

    Full Text Available ABSTRACT The characterization of species' functional traits is a major step in the understanding and description of communities in natural habitats. The classification of species into functional groups is a useful tool to identify redundancy and uniqueness. We studied the fish community of a pristine freshwater wetland in the Sian Ka'an Biosphere Reserve by analysing two multidimensional functions: food acquisition and locomotion. We investigated changes in the functional group structure between habitats (permanent and temporary pools and seasons (dry and wet. Six functional groups with different ecological characteristics were detected, two of which had high functional redundancy and three of them were represented by single species with unique ecological functions. In permanent pools during the dry season, functional group richness and diversity were lower, while evenness was higher. During the wet season, all functional groups were detected and similar functional group structure was found between habitats. These results suggest an effect of environmental filtering during the dry season and niche complementarity during the wet season.

  3. In vitro and in vivo trypanocidal activity of native plants from the Yucatan Peninsula.

    Science.gov (United States)

    Polanco-Hernández, Glendy; Escalante-Erosa, Fabiola; García-Sosa, Karlina; Acosta-Viana, Karla; Chan-Bacab, Manuel J; Sagua-Franco, Hernán; González, Jorge; Osorio-Rodríguez, Luis; Moo-Puc, Rosa E; Peña-Rodríguez, Luis M

    2012-01-01

    Ethanol extracts of Senna villosa, Serjania yucatanensis, Byrsonima bucidaefolia, and Bourreria pulchra were evaluated for their in vitro activity against epimastigotes and trypomastigotes of Trypanosoma cruzi. Results showed that the leaf extracts of S. yucatanensis and B. pulchra were the most active against epimastigotes (IC(100) = 100 μg/mL) and trypomastigotes of T. cruzi (95% or more reduction in the number of parasites at 100 and 50 μg/mL). However, only the leaf extract of S. yucatanensis showed significant trypanocidal activity when tested in vivo, reducing 75% of the parasitemia in infected mice at 100 mg/kg. This same extract inhibited the egress of trypomastigotes from infected cells and proved not to be cytotoxic (IC(50) = 318.8 ± 2.3 μg/mL).

  4. Uranium exploration in Venezuela: Situation at the end of 1978

    International Nuclear Information System (INIS)

    Pasquali, J.

    1981-01-01

    Uranium exploration started in Venezuela in 1951. The activities began with enthusiasm but interest waned because of the unfavourable economic conditions of the uranium market. In 1975, with the establishment of the National Council for the Development of the Nuclear Industry, emphasis was once again placed on exploration for radioactive minerals. Systematic exploration began 18 months ago, and so far exploratory targets have been found in phosphate rocks in Tachira state and in Palaeozoic granites at El Baul (Cojedes state); very favourable occurrences have been encountered in the Precambrian in Merida and Bolivar states, and in continental Tertiary rocks in Trujillo state. (author)

  5. Administering Our State Library Agencies

    Science.gov (United States)

    DuFrane, Gerard

    1970-01-01

    A satire on the application of scientific management principles to a state library agency. Covers relationships of the state librarian to staff, the profession, and state and federal governments. (Author/JS)

  6. State Skill Standards: Photography

    Science.gov (United States)

    Howell, Frederick; Reed, Loretta; Jensen, Capra; Robison, Gary; Taylor, Susan; Pavesich, Christine

    2007-01-01

    The Department of Education has undertaken an ambitious effort to develop statewide skill standards for all content areas in career and technical education. The standards in this document are for photography programs and are designed to clearly state what the student should know and be able to do upon completion of an advanced high-school program.…

  7. The Islamic State Unfiltered

    NARCIS (Netherlands)

    Gloerich, I.; Kolopaking, C.; Cachia, R.; Rowson, R.; Clandillon, Susan

    Instagram has become an unsuspecting pulpit ­– seemingly caught off guard – for those determined to spread a militant message of Islamic State terror. Graphic, fanatical and oftentimes heavily photoshopped images weave through Instagram’s labyrinth of sunset snaps and gym selfies to advance a

  8. Unequal Welfare States

    NARCIS (Netherlands)

    A.J. Soede; J.C. Vrooman; P.M. Ferraresi; G. Segre

    2004-01-01

    The financial sustainability of the ageing welfare states in Europe has become a key policy issue recently. This study highlights a different aspect of the ageing process, namely its potential impact on income distributions. Since older people usually live on a lower income, their growing share

  9. Reforming the Welfare State

    NARCIS (Netherlands)

    Prinz, A; Steenge, A.E.; Schmidt, J.

    2005-01-01

    The welfare state in its traditional form seems no longer sustainable. At the Rothenberge Seminar 2004, a joint venture of the School of Business, Public Administration and Technology at the University of Twente, NL, and the Institute of Public Economics at the Westfaelische Wilhelms-University

  10. Mini mental state examination

    DEFF Research Database (Denmark)

    Kørner, Ejnar Alex; Lauritzen, Lise; Wang, August

    2008-01-01

    INTRODUCTION: The Mini Mental State Examination (MMSE) is widely used in Denmark, but often in non-validated versions. In 2000 a cross-sectional workgroup decided on a new common version of the MMSE with a corresponding manual, which is validated for the first time in the present study. MATERIALS...

  11. Penn State Worry Questionnaire

    DEFF Research Database (Denmark)

    Esbjørn, Barbara Hoff; Reinholdt-Dunne, Marie Louise; Caspersen, Ida Dyhr

    2013-01-01

    and valid assessment tools are essential to identify at-risk children. The present study investigates (i) the factor structure of the Penn State Worry Questionnaire for Children (PSWQ-C) using a large Danish community sample (N¿=¿933), and (ii) its treatment sensitivity in clinically anxious children (N...

  12. Present State Examination

    DEFF Research Database (Denmark)

    Pedersen, Kamilla; Bertelsen, Aksel

    Present State Examination (PSE) 5. udgave er en revideret version af speciallæge i psykiatri Aksel Bertelsens oprindelige materiale. Aksel Bertelsen er ophavsmand til PSE og til den danske udgave af ICD-10. Revisionen omfatter et forbedret layout, en modernisering af sproget, tilføjelse af...

  13. The Liquid State

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 6. The Liquid State - The Arrangement of Atoms. K R Rao. General Article Volume 2 Issue 6 June 1997 pp 54-59. Fulltext. Click here to view fulltext PDF. Permanent link: https://www.ias.ac.in/article/fulltext/reso/002/06/0054-0059 ...

  14. Decay of Hoyle state

    Indian Academy of Sciences (India)

    2014-11-02

    Nov 2, 2014 ... The prediction of Hoyle state was necessitated to explain the abundance of carbon, which is crucial for the existence of life on Earth and is the stepping stone for understanding the abundance of other heavier elements. After the experimental confirmation of its existence, soon it was realized that the Hoyle ...

  15. The State of Kuwait

    Science.gov (United States)

    1993-04-14

    Tornado strike fighters were in the region by the end of August. 1 6 The arrival of substantial numbers of ground attack aircrafts from the United States...Safat 13002, Safat, Telex: M146151 or 46152 KT. Mansfield, Peter. Kuwait Vanguard of the Gulf. Hutchinson, London, Sydney, Auckland , Johannsberg. Sawt Al

  16. State Dependence in Unemployment

    DEFF Research Database (Denmark)

    Ahmad, Nisar

    2014-01-01

    This study examines the extent state dependence among unemployed immigrants in a dynamic discrete choice framework. Three alternative methodologies are employed to control for the problem of the initial condition. The empirical findings show that there is a considerable correlation between the un...

  17. Control of Squeezed States

    OpenAIRE

    Bloch, Anthony M.; Rojo, Alberto G.

    2000-01-01

    In this paper we consider the classical and quantum control of squeezed states of harmonic oscillators. This provides a method for reducing noise below the quantum limit and provides an example of the control of under-actuated systems in the stochastic and quantum context. We consider also the interaction of a squeezed quantum oscillator with an external heat bath.

  18. Nuclear ground state

    International Nuclear Information System (INIS)

    Negele, J.W.

    1975-01-01

    The nuclear ground state is surveyed theoretically, and specific suggestions are given on how to critically test the theory experimentally. Detailed results on 208 Pb are discussed, isolating several features of the charge density distributions. Analyses of 208 Pb electron scattering and muonic data are also considered. 14 figures

  19. Create Your State

    Science.gov (United States)

    Dunham, Kris; Melvin, Samantha

    2011-01-01

    Students are often encouraged to work together with their classmates, sometimes with other classes, occasionally with kids at other schools, but rarely with kids across the country. In this article the authors describe the Create Your State project, a collaborative nationwide project inspired by the Texas Chair Project wherein the artist, Damien…

  20. BENZODIAZEPINES IN PSYCHOTIC STATES

    OpenAIRE

    Ananth, Jambur; Solano, Olusegun

    1993-01-01

    SUMMARY Benzodiazepines are primarily used for the treatment of generalized anxiety disorder, insomnia and status epilepticus. These drugs can also be useful in hyperaroused states, catatonic stupor, manic episodes, and akathisia. This paper will review indications for their use in various psychotic conditions.

  1. State Energy Resilience Framework

    Energy Technology Data Exchange (ETDEWEB)

    Phillips, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Finster, M. [Argonne National Lab. (ANL), Argonne, IL (United States); Pillon, J. [Argonne National Lab. (ANL), Argonne, IL (United States); Petit, F. [Argonne National Lab. (ANL), Argonne, IL (United States); Trail, J. [Argonne National Lab. (ANL), Argonne, IL (United States)

    2016-12-01

    The energy sector infrastructure’s high degree of interconnectedness with other critical infrastructure systems can lead to cascading and escalating failures that can strongly affect both economic and social activities.The operational goal is to maintain energy availability for customers and consumers. For this body of work, a State Energy Resilience Framework in five steps is proposed.

  2. Highways: Interstate, US & State

    Data.gov (United States)

    Earth Data Analysis Center, University of New Mexico — This dataset contains lines for all highways in the state of New Mexico. It is in a vector digital data structure digitized from a USGS 1:500,000 scale map of the...

  3. Church and State.

    Science.gov (United States)

    National Forum: Phi Kappa Phi Journal, 1988

    1988-01-01

    Church and state is discussed in four articles: "Religiously Inspired Censorship in Public Schools" (John H. Buchanan, 34-35); "Public Funding of Education in Religious Schools" (Eugene W. Hickok, Jr., 36-38); "Neutrality in Teaching Moral Principles in Public Schools: (Francis William O'Brien, 39-40); and "The Most…

  4. The Liquid State

    Indian Academy of Sciences (India)

    Home; Journals; Resonance – Journal of Science Education; Volume 2; Issue 6. The Liquid State - The Arrangement of Atoms. K R Rao. General Article Volume 2 Issue 6 June 1997 pp 54-59. Fulltext. Click here to view fulltext PDF. Permanent link: http://www.ias.ac.in/article/fulltext/reso/002/06/0054-0059. Author Affiliations.

  5. Afghanistan, state and society

    DEFF Research Database (Denmark)

    Kværnø, Ole

    of both governmental and nongovernmental institutions from more than 20 states. Its theme was to discuss the problems that Afghanistan faces in the wake of the U.S.-led attack on al Qaeda training camps and the Taliban government; examine the challenges confronting the NATO International Security...

  6. Variational transition state theory

    Energy Technology Data Exchange (ETDEWEB)

    Truhlar, D.G. [Univ. of Minnesota, Minneapolis (United States)

    1993-12-01

    This research program involves the development of variational transition state theory (VTST) and semiclassical tunneling methods for the calculation of gas-phase reaction rates and selected applications. The applications are selected for their fundamental interest and/or their relevance to combustion.

  7. Failing Failed States

    DEFF Research Database (Denmark)

    Holm, Hans-Henrik

    2002-01-01

    from inaction. Often, the media are blamed. Politicians complain about the media when they interfere (the CNN effect), and when they do not. This article looks at how the media do cover failing states. Sierra Leone and Congo are used as examples. The analysis shows that there is little independent...

  8. Paired Hall states

    International Nuclear Information System (INIS)

    Greiter, M.

    1992-01-01

    This dissertation contains a collection of individual articles on various topics. Their significance in the corresponding field as well as connections between them are emphasized in a general and comprehensive introduction. In the first article, the author explores the consequences for macroscopic effective Lagrangians of assuming that the momentum density is proportional to the flow of conserved current. The universal corrections obtained for the macroscopic Lagrangian of a superconductor describe the London Hall effect, and provide a fully consistent derivation of it. In the second article, a heuristic principle is proposed for quantized Hall states: the existence and incompressibility of fractionally quantized Hall states is explained by an argument based on an adiabatic localization of magnetic flux, the process of trading uniform flux for an equal amount of fictitious flux attached to the particles. This principle is exactly implemented in the third article. For a certain class of model Hamiltonians, the author obtains Laughlin's Jastrow type wave functions explicitly from a filled Landau level, by smooth extrapolation in quantum statistics. The generalization of this analysis to the torus geometry shows that theorems restricting the possibilities of quantum statistics on closed surfaces are circumvented in the presence of a magnetic field. In the last article, the existence is proposed of a novel incompressible quantum liquid, a paired Hall state, at a half filled Landau level. This state arises adiabatically from free fermions in zero magnetic field, and reduces to a state previously proposed by Halperin in the limit of tightly bound pairs. It supports unusual excitations, including neutral fermions and charge e/4 anyons with statistical parameter θ = π/8

  9. Coherent states and rational surfaces

    International Nuclear Information System (INIS)

    Brody, Dorje C; Graefe, Eva-Maria

    2010-01-01

    The state spaces of generalized coherent states associated with special unitary groups are shown to form rational curves and surfaces in the space of pure states. These curves and surfaces are generated by the various Veronese embeddings of the underlying state space into higher dimensional state spaces. This construction is applied to the parameterization of generalized coherent states, which is useful for practical calculations, and provides an elementary combinatorial approach to the geometry of the coherent state space. The results are extended to Hilbert spaces with indefinite inner products, leading to the introduction of a new kind of generalized coherent states.

  10. Coherent states and rational surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Brody, Dorje C; Graefe, Eva-Maria, E-mail: d.brody@imperial.ac.u [Department of Mathematics, Imperial College London, London SW7 2AZ (United Kingdom)

    2010-06-25

    The state spaces of generalized coherent states associated with special unitary groups are shown to form rational curves and surfaces in the space of pure states. These curves and surfaces are generated by the various Veronese embeddings of the underlying state space into higher dimensional state spaces. This construction is applied to the parameterization of generalized coherent states, which is useful for practical calculations, and provides an elementary combinatorial approach to the geometry of the coherent state space. The results are extended to Hilbert spaces with indefinite inner products, leading to the introduction of a new kind of generalized coherent states.

  11. Witnessing nonclassical multipartite states

    International Nuclear Information System (INIS)

    Saguia, A.; Rulli, C. C.; Oliveira, Thiago R. de; Sarandy, M. S.

    2011-01-01

    We investigate a witness for nonclassical multipartite states based on their disturbance under local measurements. The witness operator provides a sufficient condition for nonclassicality that coincides with a nonvanishing global quantum discord, but it does not demand an extremization procedure. Moreover, for the case of Z 2 -symmetric systems, we rewrite the witness in terms of correlation functions so that classicality is found to necessarily require either vanishing magnetization in the invariant axis or isotropy of the two-point function in the transverse spin plane. We illustrate our results in quantum spin chains, where a characterization of factorized ground states (with spontaneously broken Z 2 symmetry) is achieved. As a by-product, the witness is also shown to indicate a second-order quantum phase transitions, which is illustrated for both the XY and the Ashkin-Teller spin chains.

  12. Thermodynamics of Crystalline States

    CERN Document Server

    Fujimoto, Minoru

    2013-01-01

    Thermodynamics is a well-established discipline of physics for properties of matter in thermal equilibrium with the surroundings. Applying to crystals, however, the laws encounter undefined properties of crystal lattice, which therefore need to be determined for a clear and well-defined description of crystalline states. Thermodynamics of Crystalline States explores the roles played by order variables and dynamic lattices in crystals in a wholly new way. The book begins by clarifying basic concepts for stable crystals. Next, binary phase transitions are discussed to study collective motion of order variables, as described mostly as classical phenomena. New to this edition is the examination of magnetic crystals, where magnetic symmetry is essential for magnetic phase transitions. The multi-electron system is also discussed  theoretically, as a quantum-mechanical example, for superconductivity in metallic crystals. Throughout the book, the role played by the lattice is emphasized and studied in-depth. Thermod...

  13. Di - lambpha cluster states

    International Nuclear Information System (INIS)

    Motoba, Toshio

    1982-01-01

    The lightest (p, n, Λ) closed-shell hypernucleus sub(ΛΛ) sup(6)He can be considered as a most likely candidate for the unit of hypernuclear cluster structure. First the internal structure of lambpha, α sub(Λ) = sub(ΛΛ) sup(6)He, is investigated by solving the α + Λ + Λ three-body problem microscopically. The compact h. o. wave function (0 s) 6 is found to be a good description for α sub(Λ). Secondly, by using the fully microscopic GCM, we have demonstrated that di - α sub(Λ) cluster states constitute a characteristic rotational band of J = 0 + -- 6 + . The E2 transition rate from particle - stable 2 + to 0 + states is predicted to be 2 - order faster than the weak decay rate of this system. (author)

  14. Afghanistan, state and society

    DEFF Research Database (Denmark)

    Kværnø, Ole

    In June 2007, the RAND Corporation and the Royal Danish Defence College hosted a conference titled “Afghanistan: State and Society, Great Power Politics, and the Way Ahead”. The two-day event, held in Copenhagen, was attended by more than 100 politicians, scholars, academics, and representative...... of both governmental and nongovernmental institutions from more than 20 states. Its theme was to discuss the problems that Afghanistan faces in the wake of the U.S.-led attack on al Qaeda training camps and the Taliban government; examine the challenges confronting the NATO International Security...... Assistance Force as it coordinates nation-building activities in Afghanistan; and suggest ways to address these issues. This volume compiles 11 of the papers presented at the conference; themes include the importance of historical precedents, coordination among relevant parties, and the development of an all...

  15. Parallel Polarization State Generation.

    Science.gov (United States)

    She, Alan; Capasso, Federico

    2016-05-17

    The control of polarization, an essential property of light, is of wide scientific and technological interest. The general problem of generating arbitrary time-varying states of polarization (SOP) has always been mathematically formulated by a series of linear transformations, i.e. a product of matrices, imposing a serial architecture. Here we show a parallel architecture described by a sum of matrices. The theory is experimentally demonstrated by modulating spatially-separated polarization components of a laser using a digital micromirror device that are subsequently beam combined. This method greatly expands the parameter space for engineering devices that control polarization. Consequently, performance characteristics, such as speed, stability, and spectral range, are entirely dictated by the technologies of optical intensity modulation, including absorption, reflection, emission, and scattering. This opens up important prospects for polarization state generation (PSG) with unique performance characteristics with applications in spectroscopic ellipsometry, spectropolarimetry, communications, imaging, and security.

  16. Overlaps of partial Néel states and Bethe states

    International Nuclear Information System (INIS)

    Foda, O; Zarembo, K

    2016-01-01

    Partial Néel states are generalizations of the ordinary Néel (classical anti-ferromagnet) state that can have arbitrary integer spin. We study overlaps of these states with Bethe states. We first identify this overlap with a partial version of reflecting-boundary domain-wall partition function, and then derive various determinant representations for off-shell and on-shell Bethe states. (paper: quantum statistical physics, condensed matter, integrable systems)

  17. State Controled Avantgarde?

    DEFF Research Database (Denmark)

    Kreutzfeldt, Jacob

    2016-01-01

    State controlled radio developed in the Nordic countries by the middle of the 1920es. Danish Radio was established for a trial period in April 1925, and was permanently founded in April 1926. Swedish radio was founded in 1925 and Norwegian radio in 1933. The new and unquestionably powerful medium...... to the program sheet from Danish Broadcasting Corporation (DBC) the program included transmission of music from the Radio Orchestra, sound film and transmissions from theatres and dance restaurants in Copenhage...

  18. Corruption in State Administration

    OpenAIRE

    Søreide, Tina; Rose-Ackerman, Susan

    2017-01-01

    Corruption can arise in any bureaucracy that has the authority to allocate benefits and impose costs. Program designers need to acknowledge and control such risks, but “best practice solutions” are seldom obvious. International development institutions propose long lists of anticorruption initiatives for state bureaucracies, hoping that at least some will be effective. But effective solutions in one context may be entirely ineffective in another.

  19. Algebras of Information States

    Czech Academy of Sciences Publication Activity Database

    Punčochář, Vít

    2017-01-01

    Roč. 27, č. 5 (2017), s. 1643-1675 ISSN 0955-792X R&D Projects: GA ČR(CZ) GC16-07954J Institutional support: RVO:67985955 Keywords : information states * relational semantics * algebraic semantics * intuitionistic logic * inquisitive disjunction Subject RIV: AA - Philosophy ; Religion OBOR OECD: Philosophy, History and Philosophy of science and technology Impact factor: 0.909, year: 2016

  20. Portillo's State Secrets: Mysteries

    OpenAIRE

    Clarke, David

    2015-01-01

    Blog/article commissioned by The National Archives to accompany Episode 4 of the BBC 2 series 'Portillo's State Secrets' (BBC 2, 26 March 2015). The article discusses and places in historical context the contents of Metropolitan Police files on the Jack the Ripper murders; the investigation of the 'Kitchener Coffin Hoax' of WW1 and the Ministry of Defence file on the so-called Rendlesham Forest UFO incident at RAF Woodbridge in 1980.

  1. Nevada state revenues analysis

    International Nuclear Information System (INIS)

    1988-06-01

    This report analyzes the major sources of revenue to the Nevada State General Fund for purposes of estimating impacts associated with the siting of a nuclear waste repository at Yucca Mountain in Nye County, Nevada. Each major revenue source is analyzed to identify relationships among the economic or demographic base, the revenue base, and the revenues generated. Trends and changes in the rates and/or base are highlighted. A model is developed for each revenue source to allow impact estimation

  2. The nuclear state

    International Nuclear Information System (INIS)

    Jungk, R.

    1979-01-01

    A general picture is given of the technical and sociological problems which it is said arise in the 'nuclear state'. Separate chapters are entitled: radiation fodder; the gamblers; the atomic man; the intimidated; the proliferators; atomic terrorists; the supervised. The Foreword, entitled 'the hard path' (i.e. with nuclear power) is contrasted with a final chapter entitled 'Prospect: the soft path' (i.e. without nuclear power). (U.K.)

  3. Solid State Research.

    Science.gov (United States)

    1996-05-15

    15, 324 (1993). 3. L . Wallman , J. Drott, J. Nilsson, and T. Laurell, 8th International Conference on Solid-State Sensors and Actuators and...unlimited. BTIG QUA1ETY IHSESCTBH) l This report is based on studies performed at Lincoln Laboratory, a center for research operated by Massachusetts...analyzer. 34 7-1 Fully depleted transistor results for 50-nm silicon-on-insulator thickness and W/ L = 7/0.25 fjm: (a) n-channel characteristic curves, (b

  4. Entanglement of neutrino states

    OpenAIRE

    Khokhlov, D. L.

    2007-01-01

    Muon and muon antineutrino born in the decay of charged pion form the entangled spin state. The decay of muon with the left helicity triggers the left helicity for muon antineutrino to preserve the null total angular momentum of muon and muon antineutrino. This is forbidden for antineutrino hence one cannot detect the muon antineutrino after the decay of muon. This effect may explain the deficit of muon neutrino flux in the Super-Kamiokande, K2K, MINOS experiments.

  5. Commonwealth of (Independent States

    Directory of Open Access Journals (Sweden)

    Vrućinić Dušan

    2013-01-01

    Full Text Available Following the stages from the establishment itself to the present day of the functioning of such a specific regional organization as the Commonwealth of Independent States (CIS, the article seeks to further explain the meaning of its existence, efficiency and functioning. The CIS was created in order to make the dissolution of a major world super-power, which throughout the 20th century together with the USA defined the bipolar world, as painless as possible, especially for the new countries and its nationally and ethnically diverse population. During the early years after the dissolution of the USSR, the CIS played a major role in a more flexible and less severe dissolution of the Soviet empire, alleviating the consequences for its people. A more efficient functioning among the republics in all fields was also one of the tasks of the Commonwealth, to which it was devoted to the extent which was permitted by the then, not too favourable circumstances. Difficult years of economic crisis did not allow the CIS to mutually integrate its members as much as possible on the economy level. Thanks to the economic recovery of the post-Soviet states in the early 21st century, the Commonwealth has also been transformed, reformed, and renewed, and all this in order to achieve better and more fruitful cooperation between the members. The CIS may serve as a proper example of how the former Soviet Union states are inextricably linked by social, security-political, economic, cultural, communication-transport, and other ties, thanks to the centuries-long existence of the peoples of these states in this area, despite both internal and external factors which occasionally, but temporarily halt the post-Soviet integration. Mathematically expressed, the CIS members are naturally predisposed, to be reciprocally depended on each other, just as they also have the capacity for successful cooperation in the future times and epochs brought on by the modern world.

  6. Models of multiquark states

    International Nuclear Information System (INIS)

    Lipkin, H.J.

    1986-01-01

    The success of simple constituent quark models in single-hardon physics and their failure in multiquark physics is discussed, emphasizing the relation between meson and baryon spectra, hidden color and the color matrix, breakup decay modes, coupled channels, and hadron-hadron interactions via flipping and tunneling of flux tubes. Model-independent predictions for possible multiquark bound states are considered and the most promising candidates suggested. A quark approach to baryon-baryon interactions is discussed

  7. United States advanced technologies

    International Nuclear Information System (INIS)

    Longenecker, J.R.

    1985-01-01

    In the United States, the advanced technologies have been applied to uranium enrichment as a means by which it can be assured that nuclear fuel cost will remain competitive in the future. The United States is strongly committed to the development of advanced enrichment technology, and has brought both advanced gas centrifuge (AGC) and atomic vapor laser isotope separation (AVLIS) programs to a point of significant technical refinement. The ability to deploy advanced technologies is the basis for the confidence in competitive future price. Unfortunately, the development of advanced technologies is capital intensive. The year 1985 is the key year for advanced technology development in the United States, since the decision on the primary enrichment technology for the future, AGC or AVLIS, will be made shortly. The background on the technology selection process, the highlights of AGC and AVLIS programs and the way to proceed after the process selection are described. The key objective is to maximize the sales volume and minimize the operating cost. This will help the utilities in other countries supply low cost energy on a reliable, long term basis. (Kako, I.)

  8. United States rejoin ITER

    International Nuclear Information System (INIS)

    Roberts, M.

    2003-01-01

    Upon pressure from the United States Congress, the US Department of Energy had to withdraw from further American participation in the ITER Engineering Design Activities after the end of its commitment to the EDA in July 1998. In the years since that time, changes have taken place in both the ITER activity and the US fusion community's position on burning plasma physics. Reflecting the interest in the United States in pursuing burning plasma physics, the DOE's Office of Science commissioned three studies as part of its examination of the option of entering the Negotiations on the Agreement on the Establishment of the International Fusion Energy Organization for the Joint Implementation of the ITER Project. These were a National Academy Review Panel Report supporting the burning plasma mission; a Fusion Energy Sciences Advisory Committee (FESAC) report confirming the role of ITER in achieving fusion power production, and The Lehman Review of the ITER project costing and project management processes (for the latter one, see ITER CTA Newsletter, no. 15, December 2002). All three studies have endorsed the US return to the ITER activities. This historical decision was announced by DOE Secretary Abraham during his remarks to employees of the Department's Princeton Plasma Physics Laboratory. The United States will be working with the other Participants in the ITER Negotiations on the Agreement and is preparing to participate in the ITA

  9. JWL Equation of State

    Energy Technology Data Exchange (ETDEWEB)

    Menikoff, Ralph [Los Alamos National Laboratory

    2015-12-15

    The JWL equation of state (EOS) is frequently used for the products (and sometimes reactants) of a high explosive (HE). Here we review and systematically derive important properties. The JWL EOS is of the Mie-Grueneisen form with a constant Grueneisen coefficient and a constants specific heat. It is thermodynamically consistent to specify the temperature at a reference state. However, increasing the reference state temperature restricts the EOS domain in the (V, e)-plane of phase space. The restrictions are due to the conditions that P ≥ 0, T ≥ 0, and the isothermal bulk modulus is positive. Typically, this limits the low temperature regime in expansion. The domain restrictions can result in the P-T equilibrium EOS of a partly burned HE failing to have a solution in some cases. For application to HE, the heat of detonation is discussed. Example JWL parameters for an HE, both products and reactions, are used to illustrate the restrictions on the domain of the EOS.

  10. Fermionic coherent states

    Science.gov (United States)

    Combescure, Monique; Robert, Didier

    2012-06-01

    The aim of this paper is to give a self-contained and unified presentation of a fermionic coherent state theory with the necessary mathematical details, discussing their definition, properties and some applications. After defining Grassmann algebras, it is possible to get a classical analog for the fermionic degrees of freedom in a quantum system. Following the basic work of Berezin (1966 The Method of Second Quantization (New York: Academic); 1987 Introduction to Superanalysis (Dordrecht: Reidel Publishing Company)), we show that we can compute with Grassmann numbers as we do with complex numbers: derivation, integration, Fourier transform. After that we show that we have quantization formulas for fermionic observables. In particular, there exists a Moyal product formula. As an application, we consider explicit computations for propagators with quadratic Hamiltonians in annihilation and creation operators. We prove a Mehler formula for the propagator and Mehlig-Wilkinson-type formulas for the covariant and contravariant symbols of ‘metaplectic’ transformations for fermionic states. This article is part of a special issue of Journal of Physics A: Mathematical and Theoretical devoted to ‘Coherent states: mathematical and physical aspects’.

  11. Deep inelastic final states

    International Nuclear Information System (INIS)

    Girardi, G.

    1980-11-01

    In these lectures we attempt to describe the final states of deep inelastic scattering as given by QCD. In the first section we shall briefly comment on the parton model and give the main properties of decay functions which are of interest for the study of semi-inclusive leptoproduction. The second section is devoted to the QCD approach to single hadron leptoproduction. First we recall basic facts on QCD log's and derive after that the evolution equations for the fragmentation functions. For this purpose we make a short detour in e + e - annihilation. The rest of the section is a study of the factorization of long distance effects associated with the initial and final states. We then show how when one includes next to leading QCD corrections one induces factorization breaking and describe the double moments useful for testing such effects. The next section contains a review on the QCD jets in the hadronic final state. We begin by introducing the notion of infrared safe variable and defining a few useful examples. Distributions in these variables are studied to first order in QCD, with some comments on the resummation of logs encountered in higher orders. Finally the last section is a 'gaullimaufry' of jet studies

  12. Variational transition state theory

    International Nuclear Information System (INIS)

    Truhlar, D.G.

    1986-01-01

    This project is concerned with the development and applications of generalized transition state theory and multidimensional tunneling approximations to chemical reaction rates. They have developed and implemented several practical versions of variational transition state theory (VTST), namely canonical variational theory (CVT), improved canonical variational theory (ICVT), and microcanonical variational theory (μVT). They have also developed and implemented several accurate multidimensional semiclassical tunneling approximations, the most accurate of which are the small-curvature semiclassical adiabatic (SCSA), large-curvature version-3 (LC3), and least-action (LA) approximations. They have applied the methods to thermal rate constants, using transmission coefficients based on ground-state tunneling, and they have also presented and applied adiabatic and diabatic extensions to calculated rate constants for vibrationally excited reactants. Their general goal is to develop accurate methods for calculating chemical reaction rate constants that remain practical even for reasonably complicated molecules. The approximations mentioned above yield rate constants for systems whose potential energy surface is known or assumed. Thus a second, equally important aspect of their work is the determination or modeling, semi-empirically and/or from electronic structure calculations, of potential energy surfaces

  13. 76 FR 23839 - United States

    Science.gov (United States)

    2011-04-28

    ... DEPARTMENT OF JUSTICE Antitrust Division United States v. Lucasfilm Ltd.; Public Comments and...)-(h), the United States hereby publishes below the comments received on the proposed Final Judgment in United States v. Lucasfilm Ltd., Civil Action No. 1:10-CV-02220, which was filed in the United States...

  14. Metastable states in magnetic nanorings

    DEFF Research Database (Denmark)

    Castaño, F. J.; Ross, C. A.; Frandsen, Cathrine

    2003-01-01

    Magnetization states and hysteresis behavior of small ferromagnetic rings, of diameters 180-520 nm, have been investigated using magnetic force microscopy. In addition to the expected bi-domain ("onion") and flux-closed ("vortex") magnetization states, a metastable state has been found....... This "twisted" state contains a 360degrees domain wall which can exist over a wide range of applied fields. Four possible configurations of the twisted state are possible. Micromagnetic modeling shows that the twisted state is stabilised in small diameter, narrow rings. Additionally, more complex configurations...... such as double twisted states with two 360degrees walls have been observed....

  15. Functional State Modelling of Cultivation Processes: Dissolved Oxygen Limitation State

    Directory of Open Access Journals (Sweden)

    Olympia Roeva

    2015-04-01

    Full Text Available A new functional state, namely dissolved oxygen limitation state for both bacteria Escherichia coli and yeast Saccharomyces cerevisiae fed-batch cultivation processes is presented in this study. Functional state modelling approach is applied to cultivation processes in order to overcome the main disadvantages of using global process model, namely complex model structure and a big number of model parameters. Alongwith the newly introduced dissolved oxygen limitation state, second acetate production state and first acetate production state are recognized during the fed-batch cultivation of E. coli, while mixed oxidative state and first ethanol production state are recognized during the fed-batch cultivation of S. cerevisiae. For all mentioned above functional states both structural and parameter identification is here performed based on experimental data of E. coli and S. cerevisiae fed-batch cultivations.

  16. State Energy Program Operations Manual

    Energy Technology Data Exchange (ETDEWEB)

    Office of Building Technology, State and Community Programs

    1999-03-17

    The State Energy Program Operations Manual is a reference tool for the states and the program officials at the U.S. Department of Energy's Office of Building Technology, State and Community Programs and Regional Support Offices as well as State Energy Offices. The Manual contains information needed to apply for and administer the State Energy Program, including program history, application rules and requirements, and program administration and monitoring requirements.

  17. Coherent states in quantum mechanics

    CERN Document Server

    Rodrigues, R D L; Fernandes, D

    2001-01-01

    We present a review work on the coherent states is non-relativistic quantum mechanics analysing the quantum oscillators in the coherent states. The coherent states obtained via a displacement operator that act on the wave function of ground state of the oscillator and the connection with Quantum Optics which were implemented by Glauber have also been considered. A possible generalization to the construction of new coherent states it is point out.

  18. State Clean Energy Policies Analysis (SCEPA): State Tax Incentives

    Energy Technology Data Exchange (ETDEWEB)

    Lantz, E.; Doris, E.

    2009-10-01

    As a policy tool, state tax incentives can be structured to help states meet clean energy goals. Policymakers often use state tax incentives in concert with state and federal policies to support renewable energy deployment or reduce market barriers. This analysis used case studies of four states to assess the contributions of state tax incentives to the development of renewable energy markets. State tax incentives that are appropriately paired with complementary state and federal policies generally provide viable mechanisms to support renewable energy deployment. However, challenges to successful implementation of state tax incentives include serving project owners with limited state tax liability, assessing appropriate incentive levels, and differentiating levels of incentives for technologies with different costs. Additionally, state tax incentives may result in moderately higher federal tax burdens. These challenges notwithstanding, state tax incentives that consider certain policy design characteristics can support renewable energy markets and state clean energy goals.The scale of their impact though is directly related to the degree to which they support the renewable energy markets for targeted sectors and technologies. This report highlights important policy design considerations for policymakers using state tax incentives to meet clean energy goals.

  19. Evaluation of depressive symptoms and sleep alterations in college students.

    Science.gov (United States)

    Moo-Estrella, Jesús; Pérez-Benítez, Hugo; Solís-Rodríguez, Francisco; Arankowsky-Sandoval, Gloria

    2005-01-01

    Increasing evidence suggests that sleep alterations could favor subsequent depression development. In order to identify the simultaneous occurrence of these parameters in young people, in this work we evaluated the prevalence of depressive symptoms, sleep habits, and possible sleep disturbances in college students. Beck Depression Inventory (BDI), Epworth Sleepiness Scale (ESS), and a Sleep Habits Questionnaire were applied to students registered at the Autonomous University of Yucatan, Merida (mean age 20.2 +/- 2.6 years). The final sample was composed of 340 (53%) women and 298 (47%) men. Reliability of the BDI and ESS was assessed by Cronbach's alpha method. Taking 10 as ESS cut-off point, it was found that 31.6% of the students had a high level of sleepiness. Students with depressive symptoms had a greater number of days with somnolence during class (p students without symptoms. In comparison to subjects without depressive symptoms, students with those symptoms rated their sleep quality as poor (p sleep after going to bed (p sleep alterations in a large proportion of the studied subjects, which were more severe in those who showed depressive symptoms. Educating students for appropriate sleep hygiene and encouraging them to seek professional advice to treat sleep disturbances may be useful to prevent depression.

  20. Presence of Toxoplasma gondii in Drinking Water from an Endemic Region in Southern Mexico.

    Science.gov (United States)

    Hernandez-Cortazar, Ivonne B; Acosta-Viana, Karla Y; Guzman-Marin, Eugenia; Ortega-Pacheco, Antonio; Segura-Correa, Jose C; Jimenez-Coello, Matilde

    2017-05-01

    Toxoplasmosis can be acquired through the ingestion of contaminated drinking water with oocysts of Toxoplasma gondii, highly resistant to the routinely disinfection processes; based on chlorination commonly used in the water supply industry. The aim of this study was to determine the presence of T. gondii DNA in samples of public drinking water from an endemic region of southern Mexico. In total 74 samples of water (5 L each) were collected from the three well fields (I, II, and III) and 71 independent wells, distributing public drinking water to the city of Merida Yucatan, after passing through the chlorination process. Water samples were filtered and concentrated by a sucrose solution, then DNA was extracted and evaluated through a nested-PCR (nPCR) specific for T. gondii. Positive samples were detected in 5.4% (4/74) of the water samples. This is the first report of the presence of T. gondii DNA in public drinking water from a large city in southern Mexico, where their consumption without any postpurification treatment could pose a risk for acquiring the infection in the urban population.

  1. Legislative update: United States

    International Nuclear Information System (INIS)

    Anon.

    2007-01-01

    The US Senate consented to the ratification of the Convention on Supplementary Compensation for Nuclear Damage (CSC) on 4 August 2006. The entry into force of the Convention on Supplementary Compensation will substantially change the face of the international nuclear liability regime. The CSC is a free-standing instrument, open to all states. This means that countries can become party to a new global regime providing for liability and compensation for victims of a nuclear incident, without also having to become a contracting party to the Paris Convention or the Vienna Convention. This is certainly a major step forward given that at the present time, over half of the world's reactors in operation or under construction are not covered by any of the international nuclear third party liability conventions. The CSC creates an instrument by which states can ensure that more money will be made available to compensate more victims for a broader range of damage than ever before. The CSC provides for two tiers of compensation. The first tier, fixed at 300 million Special Drawing Rights, is to be provided by the liable operator. This tier is to be distributed on a non-discriminatory basis to victims both inside and outside of the Installation State. If 300 million SDRs are insufficient to compensate all damage, then contracting parties will be required to contribute to the second tier (the international fund). The amount of this second tier is not fixed, but rather will depend on the number of operating nuclear power plants in contracting parties, and is designed to increase as the number of such plants increases

  2. Parameter and State Estimator for State Space Models

    Directory of Open Access Journals (Sweden)

    Ruifeng Ding

    2014-01-01

    Full Text Available This paper proposes a parameter and state estimator for canonical state space systems from measured input-output data. The key is to solve the system state from the state equation and to substitute it into the output equation, eliminating the state variables, and the resulting equation contains only the system inputs and outputs, and to derive a least squares parameter identification algorithm. Furthermore, the system states are computed from the estimated parameters and the input-output data. Convergence analysis using the martingale convergence theorem indicates that the parameter estimates converge to their true values. Finally, an illustrative example is provided to show that the proposed algorithm is effective.

  3. Parameter and state estimator for state space models.

    Science.gov (United States)

    Ding, Ruifeng; Zhuang, Linfan

    2014-01-01

    This paper proposes a parameter and state estimator for canonical state space systems from measured input-output data. The key is to solve the system state from the state equation and to substitute it into the output equation, eliminating the state variables, and the resulting equation contains only the system inputs and outputs, and to derive a least squares parameter identification algorithm. Furthermore, the system states are computed from the estimated parameters and the input-output data. Convergence analysis using the martingale convergence theorem indicates that the parameter estimates converge to their true values. Finally, an illustrative example is provided to show that the proposed algorithm is effective.

  4. 77 FR 72742 - Approval and Promulgation of State Implementation Plans: State of Washington; Regional Haze State...

    Science.gov (United States)

    2012-12-06

    ... rule, to each House of the Congress and to the Comptroller General of the United States. EPA will... of Representatives, and the Comptroller General of the United States prior to publication of the rule... AGENCY 40 CFR Part 52 Approval and Promulgation of State Implementation Plans: State of Washington...

  5. The State of Play

    OpenAIRE

    O'Riada, Gearoid

    2007-01-01

    La indústria dels videojocs canvia constantment. Qui juga a videojocs; per què i on són els jugadors; què passarà en el futur amb aquesta indústria multimilionària tan complexa? La industria de los videojuegos cambia constantemente. ¿Quién juega a videojuegos? ¿Por qué? ¿Dónde están los jugadores? ¿Qué deparará el futuro a esta industria multimillonaria tan compleja? The videogames industry is in a constant state of change. Who are the main players, why are they where they are, and what...

  6. Singlet Ground State Magnetism:

    DEFF Research Database (Denmark)

    Loidl, A.; Knorr, K.; Kjems, Jørgen

    1979-01-01

    The magneticGamma 1 –Gamma 4 exciton of the singlet ground state system TbP has been studied by inelastic neutron scattering above the antiferromagnetic ordering temperature. Considerable dispersion and a pronounced splitting was found in the [100] and [110] directions. Both the band width...... and the splitting increased rapidly as the transition temperature was approached in accordance with the predictions of the RPA-theory. The dispersion is analysed in terms of a phenomenological model using interactions up to the fourth nearest neighbour....

  7. Solid state phenomena

    CERN Document Server

    Lawrance, R

    1972-01-01

    Solid State Phenomena explores the fundamentals of the structure and their influence on the properties of solids. This book is composed of five chapters that focus on the electrical and thermal conductivities of crystalline solids. Chapter 1 describes the nature of solids, particularly metals and crystalline materials. This chapter also presents a model to evaluate crystal structure, the forces between atom pairs, and the mechanism of plastic and elastic deformation. Chapter 2 demonstrates random vibrations of atoms in a solid using a one-dimensional array, while Chapter 3 examines the resista

  8. Solid state mechanics

    International Nuclear Information System (INIS)

    Habib, P.

    1988-01-01

    The 1988 progress report of the Solid State Mechanics laboratory (Polytechnic School, France) is presented. The research program domains are the following: investigations concerning the stability and bifurcation of the reversible or irreversible mechanical systems, the problems related to the theoretical and experimental determination of the materials rheological properties, the fatigue crack formation and propagation in multiple-axial stress conditions, the expert systems, and the software applied in the reinforced earth structures dimensioning. Moreover, the published papers, the books, the congress communications, the thesis, and the patents are listed [fr

  9. Solid state optical microscope

    Science.gov (United States)

    Young, Ian T.

    1983-01-01

    A solid state optical microscope wherein wide-field and high-resolution images of an object are produced at a rapid rate by utilizing conventional optics with a charge-coupled photodiode array. A galvanometer scanning mirror, for scanning in one of two orthogonal directions is provided, while the charge-coupled photodiode array scans in the other orthogonal direction. Illumination light from the object is incident upon the photodiodes, creating packets of electrons (signals) which are representative of the illuminated object. The signals are then processed, stored in a memory, and finally displayed as a video signal.

  10. Regularity of Bound States

    DEFF Research Database (Denmark)

    Faupin, Jeremy; Møller, Jacob Schach; Skibsted, Erik

    2011-01-01

    We study regularity of bound states pertaining to embedded eigenvalues of a self-adjoint operator H, with respect to an auxiliary operator A that is conjugate to H in the sense of Mourre. We work within the framework of singular Mourre theory which enables us to deal with confined massless Pauli–......–Fierz models, our primary example, and many-body AC-Stark Hamiltonians. In the simpler context of regular Mourre theory, our results boil down to an improvement of results obtained recently in [8, 9]....

  11. State, religion and toleration

    DEFF Research Database (Denmark)

    Huggler, Jørgen

    2009-01-01

    Contribution to Religion and State - From separation to cooperation? Legal-philosophical reflections for a de-secularized world. (IVR Cracow Special Workshop). Eds. Bart. C. Labuschagne & Ari M. Solon. Abstract: Toleration is indeed a complex phenomenon. A discussion of the concept will have...... to underline not only the broadmindedness and liberty of individuals or of groups, but also the relevant distinctions and arguments in political philosophy, epistemology, philosophy of religion and philosophical anthropology and their connection with educational issues. Through a discussion of these relations...

  12. Solid state physics

    CERN Document Server

    Burns, Gerald

    2013-01-01

    The objective of Solid State Physics is to introduce college seniors and first-year graduate students in physics, electrical engineering, materials science, chemistry, and related areas to this diverse and fascinating field. I have attempted to present this complex subject matter in a coherent, integrated manner, emphasizing fundamental scientific ideas to give the student a strong understanding and ""feel"" for the physics and the orders of magnitude involved. The subject is varied, covering many important, sophisticated, and practical areas, which, at first, may appear unrelated but which ar

  13. Polynomial intelligent states

    Energy Technology Data Exchange (ETDEWEB)

    Milks, Matthew M; Guise, Hubert de [Department of Physics, Lakehead University, Thunder Bay, ON, P7B 5E1 (Canada)

    2005-12-01

    The construction of su(2) intelligent states is simplified using a polynomial representation of su(2). The cornerstone of the new construction is the diagonalization of a 2 x 2 matrix. The method is sufficiently simple to be easily extended to su(3), where one is required to diagonalize a single 3 x 3 matrix. For two perfectly general su(3) operators, this diagonalization is technically possible but the procedure loses much of its simplicity owing to the algebraic form of the roots of a cubic equation. Simplified expressions can be obtained by specializing the choice of su(3) operators. This simpler construction will be discussed in detail.

  14. Nuclear molecular states

    International Nuclear Information System (INIS)

    Abe, Y.

    1975-01-01

    The effects of polarization on the stability of α-cluster structures in 8 Be and 12 C nuclei are studied in the intrinsic states. The extent of the polarization of α-clusters is investigated by employing a molecular-orbital model. Two α-cluster structure of 8 Be is shown to be extremely stable, and a triangular configuration of three α-clusters is also shown to be stable, but the polarizations of α-clusters are found rather large. Gruemmer--Faessler's method is discussed and their results are shown to be trivial

  15. ECO INDUSTRIAL STATE

    Directory of Open Access Journals (Sweden)

    Mariana López Pascual

    2015-06-01

    The facades will become aesthetically pleasing for the public space or such with the installation of a new technology of a photovoltaic-glass with transparency that can be used for windows or displays. A social program of artistic murals will accompany this with the aim for awareness on environmental protection. This is a project seeks to intervene in the public space, inviting the private sector for the economic investment and nurture to gives neighbours and all Barcelona's citizens a new and attractive image of this Industrial State

  16. Local cloning of CAT states

    International Nuclear Information System (INIS)

    Rahaman, Ramij

    2011-01-01

    In this Letter we analyze the (im)possibility of the exact cloning of orthogonal three-qubit CAT states under local operation and classical communication (LOCC) with the help of a restricted entangled state. We also classify the three-qubit CAT states that can (not) be cloned under LOCC restrictions and extend the results to the n-qubit case. -- Highlights: → We analyze the (im)possibility of exact cloning of orthogonal CAT states under LOCC. → We also classify the set of CAT states that can(not) be cloned by LOCC. → No set of orthogonal CAT states can be cloned by LOCC with help of similar CAT state. → Any two orthogonal n-qubit GHZ-states can be cloned by LOCC with help of a GHZ state.

  17. State space consistency and differentiability

    CERN Document Server

    Serakos, Demetrios

    2014-01-01

    By investigating the properties of the natural state, this book presents an analysis of input-output systems with regard to the mathematical concept of state. The state of a system condenses the effects of past inputs to the system in a useful manner. This monograph emphasizes two main properties of the natural state; the first has to do with the possibility of determining the input-output system from its natural state set and the second deals with differentiability properties involving the natural state inherited from the input-output system, including differentiability of the natural state and natural state trajectories. The results presented in this title aid in modeling physical systems since system identification from a state set holds in most models. Researchers and engineers working in electrical, aerospace, mechanical, and chemical fields along with applied mathematicians working in systems or differential equations will find this title useful due to its rigorous mathematics.  

  18. State of the art

    International Nuclear Information System (INIS)

    Lederman, L.M.

    1983-01-01

    There is a large body of experience in high luminosity data taking in fixed target research. We try to consider a wide variety of high rate experiments which were limited by the detector (not by available beam) to a preset number of collisions per second. We then attempt to translate these state-of-the-art experiments to effective collider experiments. To this end, we extend the chosen detector to a comparison 4π collider detector operating near 1 TeV. There are several issues: (1) effective solid angle must be translated to approx. = 4π, (2) environments may be quite different, e.g., beam dump near fixed target or beam halo muons vs. collider backgrounds, (3) the multiplicity varies over the experiments selected and (4) we have to treat open vs closed geometries. The large variety of experiments selected is designed to average over the causes for detector limitation. Finally we chose detectors which have produced physics in order to gauge the state of the art

  19. Solid state magnetism

    CERN Document Server

    Crangle, John

    1991-01-01

    Solid state magnetism is important and attempts to understand magnetic properties have led to an increasingly deep insight into the fundamental make up of solids. Both experimental and theoretical research into magnetism continue to be very active, yet there is still much ground to cover before there can be a full understanding. There is a strong interplay between the developments of materials science and of magnetism. Hundreds of new materials have been dis­ covered, often with previously unobserved and puzzling magnetic prop­ erties. A large and growing technology exists that is based on the magnetic properties of materials. Very many devices used in everyday life involve magnetism and new applications are being invented all the time. Under­ standing the fundamental background to the applications is vital to using and developing them. The aim of this book is to provide a simple, up-to-date introduction to the study of solid state magnetism, both intrinsic and technical. It is designed to meet the needs a...

  20. State of the States: Fuel Cells in America 2015

    Energy Technology Data Exchange (ETDEWEB)

    Sandra Curtin and Jennifer Gangi

    2015-12-17

    This December 2015 report, the sixth in a series, provides a comprehensive analysis of state activities supporting fuel cell and hydrogen technology, profiles of leading states, and a catalog of recent installations, policies, funding, and deployments around the country.

  1. Federation of State Medical Boards of the United States

    Science.gov (United States)

    ... would streamline physician licensing Learn More . FSMB and state medical boards working together to protect the public ... Center » Entity Connect » Residency Records The Federation of State Medical Boards Representing the 70 medical boards of ...

  2. Set discrimination of quantum states

    International Nuclear Information System (INIS)

    Zhang Shengyu; Ying Mingsheng

    2002-01-01

    We introduce a notion of set discrimination, which is an interesting extension of quantum state discrimination. A state is secretly chosen from a number of quantum states, which are partitioned into some disjoint sets. A set discrimination is required to identify which set the given state belongs to. Several essential problems are addressed in this paper, including the condition of perfect set discrimination, unambiguous set discrimination, and in the latter case, the efficiency of the discrimination. This generalizes some important results on quantum state discrimination in the literature. A combination of state and set discrimination and the efficiency are also studied

  3. State Phobia and Civil Society

    DEFF Research Database (Denmark)

    Dean, Mitchell; Villadsen, Kaspar

    State Phobia draws extensively upon the work of Michel Foucault to argue for the necessity of the concept of the state in political and social analysis. In so doing, it takes on not only the dominant view in the human sciences that the concept of the state is outmoded, but also the large interpre......State Phobia draws extensively upon the work of Michel Foucault to argue for the necessity of the concept of the state in political and social analysis. In so doing, it takes on not only the dominant view in the human sciences that the concept of the state is outmoded, but also the large...

  4. SwingStates: adding state machines to the swing toolkit

    OpenAIRE

    Appert , Caroline; Beaudouin-Lafon , Michel

    2006-01-01

    International audience; This article describes SwingStates, a library that adds state machines to the Java Swing user interface toolkit. Unlike traditional approaches, which use callbacks or listeners to define interaction, state machines provide a powerful control structure and localize all of the interaction code in one place. SwingStates takes advantage of Java's inner classes, providing programmers with a natural syntax and making it easier to follow and debug the resulting code. SwingSta...

  5. steady – state performance of induction and transfer state ...

    African Journals Online (AJOL)

    eobe

    This paper presents paper presents paper presents the steady the steady the steady–state performance state performance state performance comparison comparison comparison between polyphase induction motor and polyphase between polyphase induction motor and polyphase. TF motor operating in. TF motor ...

  6. State distribution and reliability of some multi- state systems with ...

    African Journals Online (AJOL)

    mn : G series systems and second, the multi-state consecutive kn-out-of-mn : G parallel systems (see denitions 1 and 2).We begin by giving a non recursive formula which calculates the state distribution and the reliability of multi-state ...

  7. States of Liberation

    DEFF Research Database (Denmark)

    Sen, Somdeep

    2015-01-01

    When Hamas won the 2006 Palestinian Legislative Council elections it was a critical juncture in the life of a Palestinian faction that had, over the years, garnered the status of an iconic armed resistance. Was it viable, scholars asked, for the organization to maintain its position of resistance...... to established authority while simultaneously fulfilling its electorally-mandated responsibilities as the established government? The past years have shown that Hamas has, indeed, maintained this dual role. States of Liberation focuses on the manner in which resistance as well as governance have found meaning...... in the context of the Palestinian quest for liberation. Based on ethnographic fieldwork in the Gaza Strip, the West Bank, Israel and Egypt, this dissertation argues that resistance and governance serve as means of emboldening the signature of Palestinian existence – as a cause and as a people. Hamas’ resistance...

  8. State of the VA

    Directory of Open Access Journals (Sweden)

    Robbins RA

    2016-01-01

    Full Text Available No abstract available. Article truncated at 150 words. Earlier this week, President Obama gave his last State of the Union Address. Although this usually is a speech giving the President the opportunity of flaunt his accomplishments, no mention was made of the VA (1. Given the troubles at the VA, there seems little to tout. Over 70% of the VA medical centers were discovered to have falsified wait times (2. Because of the wait scandal, VA Secretary Eric Shinseki resigned and VA undersecretary, Robert Petzel MD, retired under pressure. Ironically, Shinseki, a retired Army general and member of the Joint Chiefs of Staff, was viewed in a favorable light by the current administration because of a spat with the Bush administration's Secretary of Defense, Donald Rumsfeld, over the number of troops needed to secure Iran and Afghanistan (3. However, during Shinseki's tenure the number of VA "medical troops", doctors and nurses, was insufficient to care for the number …

  9. Holographic Quantum States

    International Nuclear Information System (INIS)

    Osborne, Tobias J.; Eisert, Jens; Verstraete, Frank

    2010-01-01

    We show how continuous matrix product states of quantum fields can be described in terms of the dissipative nonequilibrium dynamics of a lower-dimensional auxiliary boundary field by demonstrating that the spatial correlation functions of the bulk field correspond to the temporal statistics of the boundary field. This equivalence (1) illustrates an intimate connection between the theory of continuous quantum measurement and quantum field theory, (2) gives an explicit construction of the boundary field allowing the extension of real-space renormalization group methods to arbitrary dimensional quantum field theories without the introduction of a lattice parameter, and (3) yields a novel interpretation of recent cavity QED experiments in terms of quantum field theory, and hence paves the way toward observing genuine quantum phase transitions in such zero-dimensional driven quantum systems.

  10. Geometry of Quantum States

    Energy Technology Data Exchange (ETDEWEB)

    Hook, D W [Blackett Laboratory, Imperial College of Science Technology and Medicine, University of London, Prince Consort Road, London, SW7 2BW (United Kingdom)

    2008-01-11

    A geometric framework for quantum mechanics arose during the mid 1970s when authors such as Cantoni explored the notion of generalized transition probabilities, and Kibble promoted the idea that the space of pure quantum states provides a natural quantum mechanical analogue for classical phase space. This central idea can be seen easily since the projection of Schroedinger's equation from a Hilbert space into the space of pure spaces is a set of Hamilton's equations. Over the intervening years considerable work has been carried out by a variety of authors and a mature description of quantum mechanics in geometric terms has emerged with many applications. This current offering would seem ideally placed to review the last thirty years of progress and relate this to the most recent work in quantum entanglement. Bengtsson and Zyczkowski's beautifully illustrated volume, Geometry of Quantum States (referred to as GQS from now on) attempts to cover considerable ground in its 466 pages. Its topics range from colour theory in Chapter 1 to quantum entanglement in Chapter 15-to say that this is a whirlwind tour is, perhaps, no understatement. The use of the work 'introduction' in the subtitle of GQS, might suggest to the reader that this work be viewed as a textbook and I think that this interpretation would be incorrect. The authors have chosen to present a survey of different topics with the specific aim to introduce entanglement in geometric terms-the book is not intended as a pedagogical introduction to the geometric approach to quantum mechanics. Each of the fifteen chapters is a short, and mostly self-contained, essay on a particular aspect or application of geometry in the context of quantum mechanics with entanglement being addressed specifically in the final chapter. The chapters fall into three classifications: those concerned with the mathematical background, those which discuss quantum theory and the foundational aspects of the geometric

  11. Wind turbine state estimation

    DEFF Research Database (Denmark)

    Knudsen, Torben

    2014-01-01

    the results using full-scale wind turbine data. The previously developed methods were based on extended Kalman filtering. This method has several drawback compared to unscented Kalman filtering which has therefore been developed. The unscented Kalman filter was first tested on linear and non-linear test cases......Dynamic inflow is an effect which is normally not included in the models used for wind turbine control design. Therefore, potential improvement from including this effect exists. The objective in this project is to improve the methods previously developed for this and especially to verify...... which was successful. Then the estimation of a wind turbine state including dynamic inflow was tested on a simulated NREL 5MW turbine was performed. This worked perfectly with wind speeds from low to nominal wind speed as the output prediction errors where white. In high wind where the pitch actuator...

  12. FIPRED state of art

    International Nuclear Information System (INIS)

    Ohai, D.; Meleg, T.; Dumitrescu, I.; Benga, D.

    2009-01-01

    Full text: The paper presents the FIPRED (Fission Product Release from Debris Bed) Project state of art (UO 2 sintered pellets oxidation). The FIPRED Project is dedicated to the study of the fission products released from irradiated pellets present in debris bed. The fission product release is produced by oxidative self disintegration of sintered pellets at air ingress and it depends on temperature. The experimental program covered experiments of 300-1400 deg. C in air diluted with nitrogen at different concentrations of oxygen and different steam-air mixture. The experiments were performed using the SETARAM thermo-gravimetric equipment and the FIPRED EQ equipment designed and manufactured especially for this type of experiment. The powders (fragments), resulted from UO 2 pellets self disintegration, were characterized by sieving and SEM. The self disintegration mechanism was demonstrated using the experimental result obtained and thermodynamically data of uranium oxides. (authors)

  13. Activating Welfare States

    DEFF Research Database (Denmark)

    Kvist, Jon

    This paper investigates how welfare states may actively contribute to promote employment opportunities, i.e. participation in the labour market through various operations and policies. The principal operations concern in particular the de-familiarisation of caring tasks through social services...... for children and the elderly, which in turn allows in particular women to (re-)enter the labour market, de-commodification of labour through easy accessible and relative generous cash benefits providing a more flexible labour market, and re-commodification of labour through conditioning of benefits and active...... labour market policies giving long-term unemployed and people with low skills better opportunities to participate in the labour market, whether the ordinary or in special activities....

  14. Surface states and spectra

    International Nuclear Information System (INIS)

    Jaksic, V.; Last, Y.; California Inst. of Tech., Pasadena, CA

    2001-01-01

    Let Z + d+1 =Z d x Z + , let H 0 be the discrete Laplacian on the Hilbert space l 2 (Z + d+1 ) with a Dirichlet boundary condition, and let V be a potential supported on the boundary ∂Z + d+1 . We introduce the notions of surface states and surface spectrum of the operator H=H 0 +V and explore their properties. Our main result is that if the potential V is random and if the disorder is either large or small enough, then in dimension two H has no surface spectrum on σ(H 0 ) with probability one. To prove this result we combine Aizenman-Molchanov theory with techniques of scattering theory. (orig.)

  15. Multimuon final states

    International Nuclear Information System (INIS)

    Crespo, J.-M.

    1980-04-01

    Multimuon final states have been detected by 3 experiments in the interactions of the muon beams of CERN (280 GeV) and FNAL (210 GeV) with heavy targets. For the first time production of J/PSI (3100) by space-like photons has been observed and its dependence on ν, Q 2 and t compared to Vector Dominance and photon-gluon fusion models. Also a clear signal has been seen for 3μ above QED tridents (outside J/PSI mass range) and 2μ events which are well described by charm production. An upper limit for the production of the T by high energy muons has been set

  16. Perfect and imperfect states

    Directory of Open Access Journals (Sweden)

    Nikitović Aleksandar

    2013-01-01

    Full Text Available Early Greek ethics embodied in Cretan and Spartan mores, served as a model for Plato`s political theory. Plato theorized the contents of early Greek ethics, aspiring to justify and revitalize the fundamental principles of a traditional view of the world. However, according to Plato`s new insight, deed is further from the truth than a thought i.e. theory. The dorian model had to renounce its position to the perfect prototype of a righteous state, which is a result of the inner logic of philosophical theorizing in early Greek ethics. Prototype and model of philosophical reflection, in comparison to philosophical theory, becomes minor and deficient. Philosophical theorizing of early Greek ethics philosophically formatted Greek heritage, initiating substantial changes to the content of traditional ethics. Replacement of the myth with ontology, as a new foundation of politics, transformed early Greek ethics in various relevant ways. [Projekat Ministarstva nauke Republike Srbije, br. 179049

  17. Anxiety States In Childhood

    Science.gov (United States)

    Matthews, Peter C.

    1978-01-01

    The up-to-date prevention and management of anxiety states in childhood is discussed with particular reference to the different presentations of anxiety and the ways in which preventive measures may be used. Anxiety creating developmental lag, mimicking other conditions, and appearing in very specific forms is mentioned. Techniques for handling are introduced together with some suggestions on the responsibility of the family doctor in this whole area of psychological medicine. In this article, the child is seen as part of a family setting; the effect of disturbances in the family constellation resulting in anxiety for the child is described. Some suggestions for ways in which the physician may be involved in patient and parent education are put forward. PMID:21301539

  18. Weather and emotional state

    Science.gov (United States)

    Spasova, Z.

    2010-09-01

    Introduction Given the proven effects of weather on the human organism, an attempt to examine its effects on a psychic and emotional level has been made. Emotions affect the bio-tonus, working ability and concentration, hence their significance in various domains of economic life, such as health care, education, transportation, tourism, etc. Data and methods The research has been made in Sofia City within a period of 8 months, using 5 psychological methods (Eysenck Personality Questionnaire (EPQ), State-Trait Anxiety Inventory (STAI), Test for Self-assessment of the emotional state (developed by Wessman and Ricks), Test for evaluation of moods and Test "Self-confidence - Activity - Mood" (developed by the specialists from the Military Academy in Saint Petersburg). The Fiodorov-Chubukov's complex-climatic method was used to characterize meteorological conditions because of the purpose to include in the analysis a maximal number of meteorological elements. 16 weather types are defined in dependence of the meteorological elements values according to this method. Abrupt weather changes from one day to another, defined by the same method, were considered as well. Results and discussions The results obtained by t-test show that the different categories of weather lead to changes in the emotional status, which indicates a character either positive or negative for the organism. The abrupt weather changes, according to expectations, have negative effect on human emotions but only when a transition to the cloudy weather or weather type, classified as "unfavourable" has been realized. The relationship between weather and human emotions is rather complicated since it depends on individual characteristics of people. One of these individual psychological characteristics, marked by the dimension "neuroticism", has a strong effect on emotional reactions in different weather conditions. Emotionally stable individuals are more "protected" to the weather influence on their emotions

  19. Realizing Controllable Quantum States

    Science.gov (United States)

    Takayanagi, Hideaki; Nitta, Junsaku

    1. Entanglement in solid states. Orbital entanglement and violation of bell inequalities in mesoscopic conductors / M. Büttiker, P. Samuelsson and E. V. Sukhoruk. Teleportation of electron spins with normal and superconducting dots / O. Sauret, D. Feinberg and T. Martin. Entangled state analysis for one-dimensional quantum spin system: singularity at critical point / A. Kawaguchi and K. Shimizu. Detecting crossed Andreev reflection by cross-current correlations / G. Bignon et al. Current correlations and transmission probabilities for a Y-shaped diffusive conductor / S. K. Yip -- 2. Mesoscopic electronics. Quantum bistability, structural transformation, and spontaneous persistent currents in mesoscopic Aharonov-Bohm loops / I. O. Kulik. Many-body effects on tunneling of electrons in magnetic-field-induced quasi one-dimensional systems in quantum wells / T. Kubo and Y. Tokura. Electron transport in 2DEG narrow channel under gradient magnetic field / M. Hara et al. Transport properties of a quantum wire with a side-coupled quantum dot / M. Yamaguchi et al. Photoconductivity- and magneto-transport studies of single InAs quantum wires / A. Wirthmann et al. Thermoelectric transports in charge-density-wave systems / H. Yoshimoto and S. Kurihara -- 3. Mesoscopic superconductivity. Parity-restricted persistent currents in SNS nanorings / A. D. Zaikin and S. V. Sharov. Large energy dependence of current noise in superconductingh/normal metal junctions / F. Pistolesi and M. Houzet. Generation of photon number states and their superpositions using a superconducting qubit in a microcavity / Yu-Xi Liu, L. F. Wei and F. Nori. Andreev interferometry for pumped currents / F. Taddei, M. Governale and R. Fazio. Suppression of Cooper-pair breaking against high magnetic fields in carbon nanotubes / J. Haruyama et al. Impact of the transport supercurrent on the Josephson effect / S. N. Shevchenko. Josephson current through spin-polarized Luttinger liquid / N. Yokoshi and S. Kurihara

  20. Neural-Network Quantum States, String-Bond States, and Chiral Topological States

    Directory of Open Access Journals (Sweden)

    Ivan Glasser

    2018-01-01

    Full Text Available Neural-network quantum states have recently been introduced as an Ansatz for describing the wave function of quantum many-body systems. We show that there are strong connections between neural-network quantum states in the form of restricted Boltzmann machines and some classes of tensor-network states in arbitrary dimensions. In particular, we demonstrate that short-range restricted Boltzmann machines are entangled plaquette states, while fully connected restricted Boltzmann machines are string-bond states with a nonlocal geometry and low bond dimension. These results shed light on the underlying architecture of restricted Boltzmann machines and their efficiency at representing many-body quantum states. String-bond states also provide a generic way of enhancing the power of neural-network quantum states and a natural generalization to systems with larger local Hilbert space. We compare the advantages and drawbacks of these different classes of states and present a method to combine them together. This allows us to benefit from both the entanglement structure of tensor networks and the efficiency of neural-network quantum states into a single Ansatz capable of targeting the wave function of strongly correlated systems. While it remains a challenge to describe states with chiral topological order using traditional tensor networks, we show that, because of their nonlocal geometry, neural-network quantum states and their string-bond-state extension can describe a lattice fractional quantum Hall state exactly. In addition, we provide numerical evidence that neural-network quantum states can approximate a chiral spin liquid with better accuracy than entangled plaquette states and local string-bond states. Our results demonstrate the efficiency of neural networks to describe complex quantum wave functions and pave the way towards the use of string-bond states as a tool in more traditional machine-learning applications.

  1. Neural-Network Quantum States, String-Bond States, and Chiral Topological States

    Science.gov (United States)

    Glasser, Ivan; Pancotti, Nicola; August, Moritz; Rodriguez, Ivan D.; Cirac, J. Ignacio

    2018-01-01

    Neural-network quantum states have recently been introduced as an Ansatz for describing the wave function of quantum many-body systems. We show that there are strong connections between neural-network quantum states in the form of restricted Boltzmann machines and some classes of tensor-network states in arbitrary dimensions. In particular, we demonstrate that short-range restricted Boltzmann machines are entangled plaquette states, while fully connected restricted Boltzmann machines are string-bond states with a nonlocal geometry and low bond dimension. These results shed light on the underlying architecture of restricted Boltzmann machines and their efficiency at representing many-body quantum states. String-bond states also provide a generic way of enhancing the power of neural-network quantum states and a natural generalization to systems with larger local Hilbert space. We compare the advantages and drawbacks of these different classes of states and present a method to combine them together. This allows us to benefit from both the entanglement structure of tensor networks and the efficiency of neural-network quantum states into a single Ansatz capable of targeting the wave function of strongly correlated systems. While it remains a challenge to describe states with chiral topological order using traditional tensor networks, we show that, because of their nonlocal geometry, neural-network quantum states and their string-bond-state extension can describe a lattice fractional quantum Hall state exactly. In addition, we provide numerical evidence that neural-network quantum states can approximate a chiral spin liquid with better accuracy than entangled plaquette states and local string-bond states. Our results demonstrate the efficiency of neural networks to describe complex quantum wave functions and pave the way towards the use of string-bond states as a tool in more traditional machine-learning applications.

  2. State Drug Utilization Data 2013

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  3. State Drug Utilization Data 1996

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  4. State Drug Utilization Data 1993

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  5. State Drug Utilization Data 1995

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  6. State Drug Utilization Data 1997

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  7. State Drug Utilization Data 2015

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  8. State Drug Utilization Data 1998

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  9. State Drug Utilization Data 1991

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  10. State Drug Utilization Data 1992

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  11. State Drug Utilization Data 1994

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  12. State Drug Utilization Data 2001

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  13. State Drug Utilization Data 2005

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  14. State Drug Utilization Data 2011

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  15. State Drug Utilization Data 2006

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  16. State Drug Utilization Data 2014

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  17. State Drug Utilization Data 2012

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  18. State Drug Utilization Data 2009

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  19. State Drug Utilization Data 2004

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...

  20. State Drug Utilization Data 2008

    Data.gov (United States)

    U.S. Department of Health & Human Services — Drug utilization data are reported by states for covered outpatient drugs that are paid for by state Medicaid agencies since the start of the Medicaid Drug Rebate...