1,066 research outputs found

    Seasonal Variation of Ectosymbiotic Ciliates on Farmed and Wild Shrimps from Coastal Yucatan, Mexico

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    High levels of ciliate infestation can affect respiration, feed intake, and locomotion in farmed shrimps in the tropics. Information on seasonal variation of the infestation parameters of ciliates is scarce, but it would be useful for determining the suitability of preventive measures or therapeutic treatment if necessary. This study aimed to describe the prevalence and mean intensity of infestation (MII) of ciliates on wild native shrimps Penaeus (Farfantepenaeus) brasiliensis and P. (Farfantepenaeus) duorarum and farm-cultured juvenile shrimp Penaeus (Litopenaeus) vannamei over an annual cycle and to determine whether an association existed among physicochemical factors and infestation on cultured shrimp. The ectosymbiotic ciliates Acineta tuberosa, Epistylis sp., and Zoothamnium sp. infested both farmed and wild shrimps. Based on examination of 360 farmed specimens of P. vannamei (30 examined each month), the species with highest infestation were Epistylis sp., (prevalence range = 22 –100%; MII range = 13 ± 28 – 126 ± 124) and Zoothamnium sp. (0–87%; 0 – 144 ± 132). For both species, the highest values occurred during the rainy season. A total of 288 wild specimens of P. brasiliensis plus 120 of P. duorarum obtained during three recognized seasons—dry (February to May), rainy (June to September), and north-wind (October to January)—had ciliate infestations that were significantly lower than those from farmed shrimp. For P. brasiliensis, the ciliate species with the highest infestation values were Zoothamnium sp. (0–66%; 0.03 ± 0.2 – 66 ± 92), while on P. duorarum, were for Epistylis sp. (0–46%; 0 – 8 ± 16). Using multiple linear regression, we found significant relationships between stocking density, survival, temperature, turbidity, and intensity of infestation of the ciliates. However, the regression accounted for only 11–26% of the variance (R2), meaning that there are still other environmental and biological variables that should be included to increase the reliability of the model. Thus, the physicochemical conditions of the farm increase the probability of ciliate transmission, especially during the rainy season

    Acute stress assessment using infrared thermography in fattening rabbits reacting to handling under winter and summer conditions

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    Aim of study: This study assesses acute stress by measuring, through infrared thermography in summer and winter, the temperature of the eye, outer ear, inner ear and nose in 40 fattening rabbits before and after handling.Area of study: Seville (Spain).Material and methods: Body thermographic temperatures were recorded during a 38-day fattening period twice weekly and twice a day, before and after the handler held the rabbits in their arms for one minute. Ambient temperature and relative humidity were also recorded, and their influence on body temperatures was assessed. For each anatomical part, the variation of the temperature between the handled and undisturbed rabbit, and the differential temperature between the anatomical part in the undisturbed rabbit and the ambient temperature were calculated.Main results: The variation in temperatures between handled and undisturbed rabbits ranged from 0.25±0.041 ÂșC for eye to 3.09±0.221 ÂșC for outer ear in summer and -0.41±0.182 ÂșC for nose to 2.09±0.178 ÂșC for outer ear in winter. The day of the fattening period influenced all the temperature traits during summer and winter, except for the inner ear in winter. In summer, unlike winter, the temperature variation at the end of fattening period between handled and undisturbed rabbits was lower than at weaning (-0.04 to 1.94 ÂșC vs. 0.54 to 5.52 ÂșC, respectively). The temperatures in undisturbed rabbits were correlated with ambient temperature.Research highlights: Measuring body temperature with infrared thermography is a useful tool to evaluate acute stress in handled rabbits, with the inner ear and eye the most reliable body parts for measuring it

    Evidencias empĂ­ricas de regularidades estadĂ­sticas y leyes de potencia en los genomas de arabidopsis thaliana, oriza sativa y mus musculus

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    La masiva cantidad de datos biolĂłgicos provenientes de las disciplinas “ómicas” y su aprovechamiento en el mejoramiento genĂ©tico vegetal requiere de nuevos abordajes teĂłricos y estadĂ­sticos que describan de forma satisfactoria principios generales en los genomas. El total de secuencias de los genes de los genomas vegetales de Arabidopsis thaliana y Oriza sativa y del genoma animal Mus musculus fueron extraĂ­das y depuradas de la base de datos pĂșblica del Genebank mediante el diseño de algoritmos en lenguaje de programaciĂłn Python. Se analizaron las distribuciones de las variables frecuencia de uso y tamaño de los genes, exones e intrones por cromosoma y entre genomas. Los resultados señalaron que las variables presentan patrones de comportamiento no lineales en forma de ley de potencia que difieren estadĂ­sticamente entre los genomas pero no entre los cromosomas de un mismo genoma. AdemĂĄs, el anĂĄlisis aportĂł evidencias respecto al tamaño promedio constante de las secuencias de exones y de los genes simples por cromosoma y entre genomas. Los hallazgos sugieren: primero, que el genoma se auto-organiza de la misma manera en los cromosomas independientemente del tamaño o nĂșmero de genes que estos contengan, y, segundo, que tanto los cromosomas como sus elementos constituyentes: genes, exones e intrones han evolucionado conjuntamente. El estudio señala que las leyes de potencia cumplen un papel amortiguador en las leyes de variaciĂłn biolĂłgica y proporcionan medidas cuantitativas de la organizaciĂłn de las secuencias de ADN que definen la identidad de un genoma. La regularidad estadĂ­stica de estas medidas genĂ©ticas tiene potenciales aplicaciones en el incremento del valor predictivo de los actuales modelos de mejoramiento genĂ©tico vegetal.The huge quantity of biological data arising from the omics disciplines and their benefit in plant breeding require of new theoretical and statistical approaches in order to get a satisfactory description of the genomes general principles. The total number of sequences in the genes of A. thaliana and O. sativa plant genomes and in M. musculus animal genome was obtained from the public data base of the Genebank through algoritms designed in Python programming language. The variables distribution use frequency and gene size, exons and intrones per chromosome and among genomes were analyzed. The results indicated that variable distribution show non lineal patterns of behavior in a power law form, which are statistically different among genomes but no among the chromosomes of the same genome. In the same manner the analysis gave evidences about the constant mean size of the exons sequences and the single genes per chromosome and among genomes. These findings suggest that, first, the genome is self-organized in the same way in the chromosomes independently of the size or the number of genes being contained; second, so the chromosomes as their constituent elements: genes, exones and intrones, have evolved all together. The study points out that the power laws have a buffer roll in the biological variation laws and provide DNA sequences organization quantitative measurements which are defining the identity of the genome. The statistical regularity of these genetic measurements has potential applications in the predicted value increase of the actual models of genetic plant breeding

    Kinetic investigations of quaternization reactions of poly[2‐(dimethylamino)ethyl methacrylate] with diverse alkyl halides

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    Abstract Kinetic investigations of the quaternization reactions of poly[2‐(dimethylamino)ethyl methacrylate] (PDMAEMA) with alkyl halides (1‐iodobutane, 1‐iodoheptane, and 1‐iododecane) are carried out at different temperatures. For this purpose, a PDMAEMA ( M n = 17.8 kDa, Ð = 1.35) synthesized via reversible addition fragmentation chain transfer polymerization is utilized. The progress of the quaternization reactions is followed by proton nuclear magnetic resonance. As expected, the rate of quaternization is higher with increasing temperature. The experimental data are used to determine the following kinetic parameters: order of the reaction, Arrhenius' pre‐exponential factor, and activation energy. To the best of knowledge, this is the first contribution that provides detailed kinetic data of the quaternization reactions on PDMAEMA

    Personality in patients with migraine evaluated with the "Temperament and Character Inventory"

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    The objective of this study was to assess the personality profile of a sample of Mexican patients with migraine using the Temperament and Character Inventory (TCI). A cross-sectional study was performed including adult migraine patients identified from the outpatient neurology clinics of two large teaching hospitals in Mexico City. Patients were asked to voluntarily participate in the study. A physician conducted a standardised diagnostic interview adhering to the criteria of the International Headache Society (IHS). Patients were interviewed and administered the TCI. We used two healthy controls groups and a third group of non-migraine pain controls. One hundred and fortytwo subjects with migraine, 108 healthy blood donors, 269 young healthy controls and 30 patients with non-migraine pain (NMP) were included in the study. Patients with migraine had higher scores in the dimension harm avoidance (HA) and all its sub-dimensions (p<0.05) than healthy patients. Patients with non-migraine pain had high scores in HA and low scores in novelty seeking, self-directedness and cooperativeness. Blood donors had high scores in the following subdimensions: HA1, HA4 and C3 (Cooperativeness). Personality features consistent with migraine are avoidance, rigidity, reserve and obsessivity. Our study shows that patients with chronic pain share some of the personality features of patients with migraine but their TCI profile could be indicative of cluster C avoidant personality. Blood donors were shown to have more energy, with a tendency to help other people and be more optimistic. The results support serotoninergic involvement as explaining the physiopathology of migraine

    Chicken litter: A waste or a source of chemicals? Fast pyrolysis and hydrothermal conversion as alternatives in the valorisation of poultry waste

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    Poultry production is one of the main and fastest developing branches of the agri-food industry in the world. Chicken litter (ChL) is the most abundant waste from this industry and requires alternative treatments to help mitigate the environmental impacts of improper disposal. Fast pyrolysis and hydrothermal conversion are two recognized thermochemical approaches for the transformation of different types of biomasses, including agro-industrial waste. Fast pyrolysis takes place at atmospheric pressure or under vacuum at moderate to high temperatures (400–800 °C) in the absence of oxygen and requires drying of the feedstock, whereas hydrothermal conversion is a low temperature (180–300 °C) and high pressure (up to 30 MPa) process that takes place in liquid water and particularly suited for moist materials. In this work, we present experimental results that provide a comparison of bio-oils produced by fast pyrolysis and hydrothermal conversion of ChL. In addition, the composition of the pyrolytic oils from ChL is compared with the data obtained from rice husk (the main component of ChL), studied previously. Fast pyrolysis experiments were carried out in a bed reactor at temperatures ranging from 400° to 700°C and at two reaction times of 20- and 40-min. Phenols and other oxygenated compounds were the main families of chemicals present in the bio-oils. Among oxygenated derivatives, fatty acids were predominant. Hydrothermal conversion experiments were performed between 220 and 240 °C for 20- and 40- min and the oil fraction was obtained by evaporation of water from the reaction mixture followed by freeze-drying. These bioliquids were found to be concentrated in fatty acids, especially palmitic acid.EEA ConcepciĂłn del UruguayFil: PachĂłn GĂłmez, Erica M. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂ­micas. Departamento de QuĂ­mica OrgĂĄnica. Instituto de Investigaciones en FisicoquĂ­mica de CĂłrdoba; ArgentinaFil: PachĂłn GĂłmez, Erica M. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Instituto de Investigaciones en FisicoquĂ­mica de CĂłrdoba; ArgentinaFil: DomĂ­nguez, Rodrigo E. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂ­micas. Departamento de QuĂ­mica OrgĂĄnica. Instituto de Investigaciones en FisicoquĂ­mica de CĂłrdoba; ArgentinaFil: DomĂ­nguez, Rodrigo E. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Instituto de Investigaciones en FisicoquĂ­mica de CĂłrdoba; ArgentinaFil: LĂłpez, DĂ©bora A. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂ­micas. Departamento de QuĂ­mica OrgĂĄnica. Instituto de Investigaciones en FisicoquĂ­mica de CĂłrdoba; ArgentinaFil: LĂłpez, DĂ©bora A. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Instituto de Investigaciones en FisicoquĂ­mica de CĂłrdoba; ArgentinaFil: TĂ©llez, Jhoan F. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂ­micas. Departamento de QuĂ­mica OrgĂĄnica. Instituto de Investigaciones en FisicoquĂ­mica de CĂłrdoba; ArgentinaFil: TĂ©llez, Jhoan F. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂ­micas. Departamento de FisicoquĂ­mica. Instituto de Investigaciones en FisicoquĂ­mica de CĂłrdoba; ArgentinaFil: TĂ©llez, Jhoan F. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Instituto de Investigaciones en FisicoquĂ­mica de CĂłrdoba; ArgentinaFil: Marino, Marcos D. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂ­micas. Departamento de QuĂ­mica OrgĂĄnica. Instituto de Investigaciones en FisicoquĂ­mica de CĂłrdoba; ArgentinaFil: Marino, Marcos D. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Instituto de Investigaciones en FisicoquĂ­mica de CĂłrdoba; ArgentinaFil: Almada, Natalia Soledad. Instituto Nacional de TecnologĂ­a Agropecuaria (INTA). EstaciĂłn Experimental Agropecuaria ConcepciĂłn del Uruguay; Argentina.Fil: Gange, Juan Martí­n. Instituto Nacional de TecnologĂ­a Agropecuaria (INTA). EstaciĂłn Experimental Agropecuaria ConcepciĂłn del Uruguay; ArgentinaFil: Moyano, E. Laura. Universidad Nacional de CĂłrdoba. Facultad de Ciencias QuĂ­micas. Departamento de QuĂ­mica OrgĂĄnica. Instituto de Investigaciones en FisicoquĂ­mica de CĂłrdoba; ArgentinaFil: Moyano, E. Laura. Consejo Nacional de Investigaciones CientĂ­ficas y TĂ©cnicas. Instituto de Investigaciones en FisicoquĂ­mica de CĂłrdoba; Argentin
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