Background: There is no previous evidence in the literature that documents the presence of extraf... more Background: There is no previous evidence in the literature that documents the presence of extrafloral nectaries (EFNs) or the exomorphology of domatia in Nephelium lappaceum (rambutan), a fruit tree native to Malaysia introduced in various American countries. Question: It is the presence of EFNs responsible for the frequent visit of ants to young leaves of Nephelium lappaceum? Study site and dates: This study was conducted in a commercial rambutan orchard in the town of Francisco I. Madero, municipality of Frontera Hidalgo (Chiapas, Mexico) during the period September 2020-February 2021. Methods: External morphology of EFNs and domatia were studied using scanning electron microscopy. Nectar sugar concentration produced by EFNs was determined by refractometry. EFNs location on the plant and the frequency of visiting ants were quantified by visual counting. Results: A description of the external morphology of EFNs and domatia, as well as their location on rambutan leaflets are presen...
Abstract. Parasitism by Cirrhencyrtus spp. on Ferrisia virgata Cock and Dysmicoccus brevipes Cock... more Abstract. Parasitism by Cirrhencyrtus spp. on Ferrisia virgata Cock and Dysmicoccus brevipes Cockerell associated with rambutan (Nephelium lappaceum L.) crops in Mexico was reported. Parasitoids were randomly sampled in six commercial orchards where synthetic insecticide was not applied. Parasitism by Cirrhencyrtus aeoles (Noyes), Cirrhencyrtus silvia (Noyes), and Cirrhencyrtus pertius (Noyes) was recorded in 15 samples at four localities from 504 samples collected at six localities. This is the first record of these parasitoids in Mexico and new host associations.
Background Insecticide use continues as the main strategy to control Aedes aegypti, the vector of... more Background Insecticide use continues as the main strategy to control Aedes aegypti, the vector of dengue, Zika, chikungunya, and yellow fever. In the city of Tapachula, Mexico, mosquito control programs switched from pyrethroids to organophosphates for outdoor spatial spraying in 2013. Additionally, the spraying scheme switched from total coverage to focused control, prioritizing areas with higher entomological-virological risk. Five years after this strategy had been implemented, we evaluated the status and variability of insecticide resistance among Ae. aegypti collected at 26 sites in Tapachula. Methodology/Principal findings We determined the lethal concentrations at 50% of the tested populations (LC50) using a bottle bioassay, and then, we calculated the resistance ratio (RR) relative to the susceptible New Orleans strain. Permethrin and deltamethrin (pyrethroids), chlorpyrifos and malathion (organophosphates), and bendiocarb (carbamate) were tested. The frequencies of the subs...
Objetivo. Determinar la resistencia a insecticidas en Ae. aegypti y Ae. albopictus de Tapachula,... more Objetivo. Determinar la resistencia a insecticidas en Ae. aegypti y Ae. albopictus de Tapachula, Chiapas, México. Material y métodos. Se utilizaron ovitrampas para obtener huevos de mosquitos Aedes y se realizaron pruebas de susceptibilidad (CDC) y ensayos enzimáticos con la primera generación. Resultados. Aedes aegypti mostró resistencia a deltametrina, permetrina, malatión, clorpirifos, temefos y a bendiocarb (CARB), mientras que Aedes albopictus a malatión y en menor grado a cloripirifos, temefos, permetrina y deltametrina. Ambas especies mostraron altos niveles de enzimas como citocomo P450 y glutatión S-tranferasa, mientras que los niveles de esterasas variaron por especie y sitio muestreado. Se detectó acetilcolinesterasa insensible a insecticidas en ambas especies. Conclusión. En un hábitat urbano de Tapachula, Chiapas, México donde se aplica control con insecticidas Ae. aegypti y Ae. albopictus sólo son susceptibles al propoxur.
Se muestran los resultados de la búsqueda de Leishmania y Wolbachia mediante PCR, en flebotominos... more Se muestran los resultados de la búsqueda de Leishmania y Wolbachia mediante PCR, en flebotominos recolectados durante 2011 (febrero-marzo) en cafetales de cuatro localidades ubicadas dentro de un transecto altitudinal en la región del Soconusco, Chiapas, México. Las especies Lutzomyia texana y Lu. carpenteri son documentadas por primera vez para el estado de Chiapas. Wolbachia fue detectada en una hembra de Lutzomyia cruciata capturada en la Finca Guadalupe Sajú. Todas las muestras fueron negativas a Leishmania.
Fundamento y objetivos Las verrugas son uno de los principales problemas en dermatologia. En part... more Fundamento y objetivos Las verrugas son uno de los principales problemas en dermatologia. En particular, la eliminacion de las verrugas de la cara. De los multiples tratamientos, la inmunoterapia ha demostrado ser un metodo efectivo, y la candidina es un importante inmunoestimulador. Se evalua la eficiencia de la candidina intralesional en el tratamiento de verrugas virales planas en la cara. Pacientes y metodo Se realizo un estudio experimental con 30 pacientes de cualquier sexo, mayores de 5 anos de edad, provenientes de la consulta externa de dermatologia con el diagnostico de verrugas virales planas en la cara. Se excluyo a los pacientes con algun grado de inmunodepresion o que estuvieran con inmunoterapia. Se aplico 0,1 ml de candidina en la primera lesion y, cada 4 semanas, una segunda y una tercera dosis. Se evaluo el indice de curacion. Resultados Se evaluaron los resultados en 20 varones y 10 mujeres de entre 5 y 46 anos de edad. La evolucion de las lesiones fue de entre 1 y 60 meses. Las verrugas de 10 pacientes desaparecieron y 20 no respondieron al tratamiento. Conclusiones La candidina intralesional es una buena alternativa para el tratamiento de verrugas virales planas en la cara. El mecanismo inmunitario es primeramente local y luego, sistemico.
... As a result of this quality control, we believe that the DST temperature profiles in all ... ... more ... As a result of this quality control, we believe that the DST temperature profiles in all ... Correction factor f S (see Equation (2)) for individual wireline temperatures plotted versus time since ... DST measurements and the corrected value of a temperature measured during a logging run. ...
A method for correcting log-derived temperatures in deep wells (3500-6500 m) has been developed b... more A method for correcting log-derived temperatures in deep wells (3500-6500 m) has been developed by comparing log temperatures from the Gulf of Campeche (Mexican Gulf of Mexico) with DST temperatures in the same wells. The equations developed in this study are modified slightly from those of Waples & Mahadir Ramly (2001), which were calibrated using data from depths <3500 m in Malaysia. The correction depends strongly on time since end of mud circulation (TSC) and, to a much lesser degree, on depth. In this study the true subsurface temperature (Celsius) is given by T true =T surf +f•(T meas T surf) 0.001391(Z 4498) where f=1.32866 0.005289TSC , T surf is the seafloor or land-surface temperature (C), T meas is the measured log temperature (C), TSC is in hours and Z is depth below seafloor in metres. If TSC is unknown, it can be estimated from the trend of TSC with depth. An estimate of the uncertainty in the corrected temperature is obtained from the equation: =0.10842 0.029TSC where is the standard deviation of the correction factor f. The uncertainty in the correction factor f can be expressed as 2 .
Background: There is no previous evidence in the literature that documents the presence of extraf... more Background: There is no previous evidence in the literature that documents the presence of extrafloral nectaries (EFNs) or the exomorphology of domatia in Nephelium lappaceum (rambutan), a fruit tree native to Malaysia introduced in various American countries. Question: It is the presence of EFNs responsible for the frequent visit of ants to young leaves of Nephelium lappaceum? Study site and dates: This study was conducted in a commercial rambutan orchard in the town of Francisco I. Madero, municipality of Frontera Hidalgo (Chiapas, Mexico) during the period September 2020-February 2021. Methods: External morphology of EFNs and domatia were studied using scanning electron microscopy. Nectar sugar concentration produced by EFNs was determined by refractometry. EFNs location on the plant and the frequency of visiting ants were quantified by visual counting. Results: A description of the external morphology of EFNs and domatia, as well as their location on rambutan leaflets are presen...
Abstract. Parasitism by Cirrhencyrtus spp. on Ferrisia virgata Cock and Dysmicoccus brevipes Cock... more Abstract. Parasitism by Cirrhencyrtus spp. on Ferrisia virgata Cock and Dysmicoccus brevipes Cockerell associated with rambutan (Nephelium lappaceum L.) crops in Mexico was reported. Parasitoids were randomly sampled in six commercial orchards where synthetic insecticide was not applied. Parasitism by Cirrhencyrtus aeoles (Noyes), Cirrhencyrtus silvia (Noyes), and Cirrhencyrtus pertius (Noyes) was recorded in 15 samples at four localities from 504 samples collected at six localities. This is the first record of these parasitoids in Mexico and new host associations.
Background Insecticide use continues as the main strategy to control Aedes aegypti, the vector of... more Background Insecticide use continues as the main strategy to control Aedes aegypti, the vector of dengue, Zika, chikungunya, and yellow fever. In the city of Tapachula, Mexico, mosquito control programs switched from pyrethroids to organophosphates for outdoor spatial spraying in 2013. Additionally, the spraying scheme switched from total coverage to focused control, prioritizing areas with higher entomological-virological risk. Five years after this strategy had been implemented, we evaluated the status and variability of insecticide resistance among Ae. aegypti collected at 26 sites in Tapachula. Methodology/Principal findings We determined the lethal concentrations at 50% of the tested populations (LC50) using a bottle bioassay, and then, we calculated the resistance ratio (RR) relative to the susceptible New Orleans strain. Permethrin and deltamethrin (pyrethroids), chlorpyrifos and malathion (organophosphates), and bendiocarb (carbamate) were tested. The frequencies of the subs...
Objetivo. Determinar la resistencia a insecticidas en Ae. aegypti y Ae. albopictus de Tapachula,... more Objetivo. Determinar la resistencia a insecticidas en Ae. aegypti y Ae. albopictus de Tapachula, Chiapas, México. Material y métodos. Se utilizaron ovitrampas para obtener huevos de mosquitos Aedes y se realizaron pruebas de susceptibilidad (CDC) y ensayos enzimáticos con la primera generación. Resultados. Aedes aegypti mostró resistencia a deltametrina, permetrina, malatión, clorpirifos, temefos y a bendiocarb (CARB), mientras que Aedes albopictus a malatión y en menor grado a cloripirifos, temefos, permetrina y deltametrina. Ambas especies mostraron altos niveles de enzimas como citocomo P450 y glutatión S-tranferasa, mientras que los niveles de esterasas variaron por especie y sitio muestreado. Se detectó acetilcolinesterasa insensible a insecticidas en ambas especies. Conclusión. En un hábitat urbano de Tapachula, Chiapas, México donde se aplica control con insecticidas Ae. aegypti y Ae. albopictus sólo son susceptibles al propoxur.
Se muestran los resultados de la búsqueda de Leishmania y Wolbachia mediante PCR, en flebotominos... more Se muestran los resultados de la búsqueda de Leishmania y Wolbachia mediante PCR, en flebotominos recolectados durante 2011 (febrero-marzo) en cafetales de cuatro localidades ubicadas dentro de un transecto altitudinal en la región del Soconusco, Chiapas, México. Las especies Lutzomyia texana y Lu. carpenteri son documentadas por primera vez para el estado de Chiapas. Wolbachia fue detectada en una hembra de Lutzomyia cruciata capturada en la Finca Guadalupe Sajú. Todas las muestras fueron negativas a Leishmania.
Fundamento y objetivos Las verrugas son uno de los principales problemas en dermatologia. En part... more Fundamento y objetivos Las verrugas son uno de los principales problemas en dermatologia. En particular, la eliminacion de las verrugas de la cara. De los multiples tratamientos, la inmunoterapia ha demostrado ser un metodo efectivo, y la candidina es un importante inmunoestimulador. Se evalua la eficiencia de la candidina intralesional en el tratamiento de verrugas virales planas en la cara. Pacientes y metodo Se realizo un estudio experimental con 30 pacientes de cualquier sexo, mayores de 5 anos de edad, provenientes de la consulta externa de dermatologia con el diagnostico de verrugas virales planas en la cara. Se excluyo a los pacientes con algun grado de inmunodepresion o que estuvieran con inmunoterapia. Se aplico 0,1 ml de candidina en la primera lesion y, cada 4 semanas, una segunda y una tercera dosis. Se evaluo el indice de curacion. Resultados Se evaluaron los resultados en 20 varones y 10 mujeres de entre 5 y 46 anos de edad. La evolucion de las lesiones fue de entre 1 y 60 meses. Las verrugas de 10 pacientes desaparecieron y 20 no respondieron al tratamiento. Conclusiones La candidina intralesional es una buena alternativa para el tratamiento de verrugas virales planas en la cara. El mecanismo inmunitario es primeramente local y luego, sistemico.
... As a result of this quality control, we believe that the DST temperature profiles in all ... ... more ... As a result of this quality control, we believe that the DST temperature profiles in all ... Correction factor f S (see Equation (2)) for individual wireline temperatures plotted versus time since ... DST measurements and the corrected value of a temperature measured during a logging run. ...
A method for correcting log-derived temperatures in deep wells (3500-6500 m) has been developed b... more A method for correcting log-derived temperatures in deep wells (3500-6500 m) has been developed by comparing log temperatures from the Gulf of Campeche (Mexican Gulf of Mexico) with DST temperatures in the same wells. The equations developed in this study are modified slightly from those of Waples & Mahadir Ramly (2001), which were calibrated using data from depths <3500 m in Malaysia. The correction depends strongly on time since end of mud circulation (TSC) and, to a much lesser degree, on depth. In this study the true subsurface temperature (Celsius) is given by T true =T surf +f•(T meas T surf) 0.001391(Z 4498) where f=1.32866 0.005289TSC , T surf is the seafloor or land-surface temperature (C), T meas is the measured log temperature (C), TSC is in hours and Z is depth below seafloor in metres. If TSC is unknown, it can be estimated from the trend of TSC with depth. An estimate of the uncertainty in the corrected temperature is obtained from the equation: =0.10842 0.029TSC where is the standard deviation of the correction factor f. The uncertainty in the correction factor f can be expressed as 2 .
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