Growth aspects of the marine microalga Nannochloropsis gaditana

Nannochloropsis is well appreciated in aquaculture due to its nutritional value and the ability to produce valuable chemical compounds, such as pigments (zeaxanthin, astaxanthin...) and polyunsaturated fatty acids (EPA). Commercial exploitation needs high cell densities but the low growth rate and the small size of cells are practical difficulties. To increase biomass concentration the positive effect of several factors was evident: (i) pH[approximate]8 control (with dilute Tris-HCl buffer); (ii) the continuous illumination (no evidence of photo-inhibition was observed); (iii) a quite large temperature range (25±5 °C); (iv) the presence of organic carbon source (with the danger of contamination); (v) the presence of urea as an additional nitrogen source (10 mM); (vi) a small air flow rate with large bubbles can be more efficient for CO2 mass transfer (associated to reduced shearing).http://www.sciencedirect.com/science/article/B6VRM-492W13D-4/1/d65b11cf23c3d0795406c391c335446

Caracterización genética de ovinos criollos colombianos

ABSTRACT: indigenous breeds are important for poor farmers because of their natural selection against harsh environments and adaptation to regional conditions. However, inbreeding of indigenous sheep populations has increased in Colombia due to indiscriminate cross-breeding with foreign animals and lack of reproductive controls, with subsequent loss in productivity, which poses a great risk for the conservation of valuable genes. Objective: to determine the genetic diversity in Colombian indigenous sheep by using a panel of 10 microsatellite molecular markers. Methods: blood samples from 362 individuals from 43 farms in 11 Colombian provinces were genotyped and analyzed for a panel of 10 microsatellite markers. Results: a total of 134 alleles were found (13.4 alleles/locus on average) with a range of observed and expected heterozygosity of 0.428 to 0.831 and 0.615 to 0.855, respectively, and 0.742 polymorphic information content (PIC). The average Wright F-statistics (FIS ) of the breeds was 0.107, suggesting moderate levels of inbreeding. Colombian sheep showed a low level of genetic differentiation among breeds (FST = 0.054) and STRUCTURE analysis showed complex patterns of admixture in the breeds. Conclusion: overall, Colombian sheep have high genetic variability, which is very important for future conservation programs and genetic improvement.RESUMEN: las razas animales autóctonas son importantes para los agricultores de escasos recursos a causa de su selección natural contra el duro ambiente y su adaptación a condiciones regionales. Sin embargo en Colombia, debido al cruce indiscriminado con razas foráneas y a la falta de control de la reproducción, ha aumentado la consanguinidad en las poblaciones de ovinos criollos y por lo tanto la pérdida en la productividad, lo que supone un gran riesgo para la conservación de genes valiosos. Objetivo: determinar la diversidad genética en razas criollas de ovinos colombianos utilizando análisis por microsatélites. Métodos: se visitaron 43 granjas localizadas en 11 departamentos del país, en las cuales se tomaron muestras de sangre a 362 individuos. Las muestras fueron genotipadas y analizadas para un panel de 10 marcadores microsatélites. Resultados: un total de 134 alelos fueron encontrados (13,4 alelos/locus en promedio), con un rango de heterocigocidad observada y esperada de 0,428 a 0,831 y 0,615 a 0,855, respectivamente, y un contenido de información polimórfica (PIC) promedio de 0,742. El Wright F-statistics (FIS) promedio de las razas evaluadas fue 0,107, lo cual sugiere que las razas tienen niveles moderados de consanguinidad. Las ovejas colombianas presentaron un bajo grado de diferenciación genética entre las distintas razas (FST = 0,054) y el análisis de STRUCTURE mostro complejos patrones de mezcla en las razas estudiadas. Conclusión: en términos generales, las ovejas colombianas presentan una alta variabilidad genética lo cual es muy importante para futuros programas de conservacion y mejoramiento genetico

NO/H2S "crosstalk" Reactions. The Role of Thionitrites (SNO-) and Perthionitrites (SSNO-)

The redox chemistry of H2S with NO and other oxidants containing the NO group is discussed on a mechanistic basis because of the expanding interest in their biological relevance, with an eye open to the chemical differences of H2S and thiols RSH. We focus on the properties of two "crosstalk" intermediates, SNO- (thionitrite) and SSNO- (perthionitrite, nitrosodisulfide) based in the largely controversial status on their identity and chemistry in aqueous/nonaqueous media, en route to the final products N2O, NO2 -, NH2OH/NH3, and S8. Thionitrous acid, generated either in the direct reaction of NO + H2S or through the transnitrosation of RSNO's (nitrosothiols) with H2S at pH 7.4, is best described as a mixture of rapidly interconverting isomers, {(H)SNO}. It is reactive in different competitive modes, with a half-life of a few seconds at pH 7.4 for homolytic cleavage of the N-S bond, and could be deprotonated at pH values of up to ca. 10, giving SNO-, a less reactive species than {(H)SNO}. The latter mixture can also react with HS-, giving HNO and HS2 - (hydrogen disulfide), a S0(sulfane)-transfer reagent toward {(H)SNO}, leading to SSNO-, a moderately stable species that slowly decomposes in aqueous sulfide-containing solutions in the minute-hour time scale, depending on [O2]. The previous characterization of HSNO/SNO- and SSNO- is critically discussed based on the available chemical and spectroscopic evidence (mass spectrometry, UV-vis, 15N NMR, Fourier transform infrared), together with computational studies including quantum mechanics/molecular mechanics molecular dynamics simulations that provide a structural and UV-vis description of the solvatochromic properties of cis-SSNO- acting as an electron donor in water, alcohols, and aprotic acceptor solvents. In this way, SSNO- is confirmed as the elusive "yellow intermediate" (I412) emerging in the aqueous crosstalk reactions, in contrast with its assignment to polysulfides, HSn -. The analysis extends to the coordination abilities of {(H)SNO}, SNO-, and SSNO- into heme and nonheme iron centers, providing a basis for best unraveling their putative specific signaling roles.Fil: Marcolongo, Juan Pablo. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Venâncio, Mateus F.. Universidade Federal de Minas Gerais; BrasilFil: Rocha, Willian R.. Universidade Federal de Minas Gerais; BrasilFil: Doctorovich, Fabio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; ArgentinaFil: Olabe Iparraguirre, Jose Antonio. Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Ciudad Universitaria. Instituto de Química, Física de los Materiales, Medioambiente y Energía. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Química, Física de los Materiales, Medioambiente y Energía; Argentin

Estudio de tráfico sobre una plataforma de virtualización

Copy topologies characteristics of real net-works in virtual scenario, it is a recent tech-nology and in constant development. This virtualization, get “machines”, scenarios, hardware and other factors size the ser vice of ser vices of networks. In this investigation, there is examined the implementation of a virtualization platform of users ser vices in a company which principal head offi ce in Co-lombia, It is in the Bogota city. The platform suffering from a direct way the bandwidth of the company’s branches channels, affecting the user s productivity and the company it-self. This article describes the study of the virtualization impact, from the traffi c pers-pective, with the purpose of demonstrating that company’s branches are capable to en-largement in the channel capacity and which ones might support the virtualization with the current capacity, so that unnecessar y expenses are not generated, transported on having extended the channels of indiscrimi-nate form.La reproducción de características topológicas de redes reales en escenariosvirtuales, es una tecnología reciente y en constante desarrollo.Esta virtualización, comprende “máquinas”, escenarios, herramientasy demás factores que dimensionan la prestación de servicios de redes.En este trabajo, se examina la implementación de una plataforma devirtualización de los servicios de los usuarios en una empresa cuyasede principal en Colombia, se encuentra en la ciudad de Bogotá. Dichaplataforma afecta de manera directa el ancho de banda de los canalesde las sucursales de la empresa, afectando la productividad delos usuarios y de la empresa misma. Este artículo describe el estudiodel impacto de la virtualización, desde la perspectiva del tráfi co, con lafi nalidad de evidenciar qué sucursales son susceptibles a ampliaciónen la capacidad del canal y cuales podrían soportar la virtualización conla capacidad actual, de modo que no se generen gastos innecesarios,acarreados al ampliar los canales de forma indiscriminada

Estudio de tráfico sobre una plataforma de virtualización

La reproducción de características topológicas de redes reales en escenariosvirtuales, es una tecnología reciente y en constante desarrollo.Esta virtualización, comprende “máquinas”, escenarios, herramientasy demás factores que dimensionan la prestación de servicios de redes.En este trabajo, se examina la implementación de una plataforma devirtualización de los servicios de los usuarios en una empresa cuyasede principal en Colombia, se encuentra en la ciudad de Bogotá. Dichaplataforma afecta de manera directa el ancho de banda de los canalesde las sucursales de la empresa, afectando la productividad delos usuarios y de la empresa misma. Este artículo describe el estudiodel impacto de la virtualización, desde la perspectiva del tráfi co, con lafi nalidad de evidenciar qué sucursales son susceptibles a ampliaciónen la capacidad del canal y cuales podrían soportar la virtualización conla capacidad actual, de modo que no se generen gastos innecesarios,acarreados al ampliar los canales de forma indiscriminada

Genetic characterization of Colombian indigenous sheep

Background: indigenous breeds are important for poor farmers because of their natural selection against harsh environments and adaptation to regional conditions. However, inbreeding of indigenous sheep populations has increased in Colombia due to indiscriminate cross-breeding with foreign animals and lack of reproductive controls, with subsequent loss in productivity, which poses a great risk for the conservation of valuable genes. Objective: to determine the genetic diversity in Colombian indigenous sheep by using a panel of 10 microsatellite molecular markers. Methods: blood samples from 362 individuals from 43 farms in 11 Colombian provinces were genotyped and analyzed for a panel of 10 microsatellite markers. Results: a total of 134 alleles were found (13.4 alleles/locus on average) with a range of observed and expected heterozygosity of 0.428 to 0.831 and 0.615 to 0.855, respectively, and 0.742 polymorphic information content (PIC). The average Wright F-statistics (FIS) of the breeds was 0.107, suggesting moderate levels of inbreeding. Colombian sheep showed a low level of genetic differentiation among breeds (FST = 0.054) and STRUCTURE analysis showed complex patterns of admixture in the breeds. Conclusion: overall, Colombian sheep have high genetic variability, which is very important for future conservation programs and genetic improvement

In search of international quality: The library experience with WASC

This research is based on the experience, changes and processes that the library system of CETYS Universidad has undergone from 2004 to 2014. In this period, CETYS has achieved international certification by the American organization named Western Association of Schools and Colleges (WASC), making it the first university in Mexico to receive this accreditation. This work highlights the preparations, plans and changes that the library system was required to develop, in order to support the achievement of the accreditation in 2011 and the programmed adjustments that need to be taken into account to maintain such accreditation in 2016. The evidence and data collection method used was a survey; its preliminary results, may be of interest to similar universities working toward accreditations of the same kind

Gamma Irradiation Effect of

In order to know the influence of 60Co gamma radiation, on the germination of two semitropical species, roselle seeds and sunflower were irradiated at the Transelektro LGI-01 of the InstitutoNacional de InvestigacionesNucleares, At doses 0, 5, 10, 15, 20, 25, 30 and 35 Gy, to determine the radiosensitivity curve and to determine the LD50 of both species, under a randomized complete block design with factorial arrangement, Where the study factors were: radiation doses and species. The results indicate that sunflower is more sensitive to gamma radiation than roselle, so the LD50 for sunflower and roselle was not reached, because the doses of radiation used, did not achieve 0% germination. Thus, the radiosensitivity curves were fitted to a linear model, with a high coefficient of determination. From the present investigation, It can be concluded that to determine the LD50 in the species in question, It is necessary to increase the dose of irradiation, perhaps up to 1000 Gy

In vitro dissolution characteristics of patent, generic and similar brands of naproxen in various dissolution media

Purpose: To investigate the dissolution properties of various brands of naproxen in four dissolution media in order to forecast their biological availability. Methods: Dissolution tests were carried out in a dissolution tester with 48 tablets of different naproxen brands in 900 mL of 0.1 M phosphate buffer, pH 7.4. Subsequently, the medium was modified with 600 mL of buffer plus 300 mL of cola drink, grapefruit or milk. Each sample was taken and brought to a concentration approximating that of a reference solution. Absorbance at 332 nm was determined and the dissolution, Q, was calculated (Q values ≥ 80.0 ± 5 % were acceptable). Results: Dissolution in buffer was > 85 %. In cola drink, it was < 80 %, while in grapefruit juice, it was in the range of 7 - 68 %. Using 2-way ANOVA, these media and the three naproxen brands showed significant differences (F = 68.90, p = 0.0000; F = 23.18, p = 0.0000). With Fisher's LSD test, two of these media contributed consistently to dissolution, and the three drug brands showed statistically different dissolution profiles (p ≤ 0.05). Conclusion: Caution must be exercised cola drink, grapefruit juice and milk are used to administered naproxen as the biological availability of the drug may be altered

Effect of Nitrogen on Agronomic Yield, Spad Units and Nitrate Content in Roselle (Hibiscus Sabdariffal.) in Dry Weather

This study was conducted in polyethylene bags of 4 kg capacity with plants of Jamaica from seeds collected from an accession on the coast of Oaxaca, which were planted under the ecological conditions of Teotitlán de Flores Magón, and evaluated under completely randomized design, where treatments were four levels of nitrogen: 0, 50, 100 and 150 kg ha-1 and four repetitions (4x4) = 16 experimental units. The variables evaluated were: both agronomic yields: chalice and seed, harvest index, SPAD units and nitrate content in leaf. The results indicate that higher yields ofseed and chalice, biomass, nitrate content in leaf and SPAD units were achieved with the application of 100 kg ha-1 of nitrogen with 50.39, 196.80, 620.4 g plant-1, 85.00 mg kg-1 and 29.10 units, respectively. The content of nitrates and its relationship with SPAD units, adjusted to an increasing linear model for the four levels of nitrogen studied. From this study it can be concluded that the application of 100 kg N ha-1, positively affect the culture of Jamaica under dry weather conditions way