75 research outputs found

    Hábitos alimenticios y percepción de las personas hacia la Lechuza blanca (Tyto alba tuidara, J.E.Gray 1829) en un barrio urbano del sur de Chile: Implicancias para la conservación

    Get PDF
    People’s perception on birds of prey is heavily infl uenced by its intrinsic value, utility, myths and superstitions. In particular, negative perceptions may encourage poaching and persecution of these birds, affecting their conservation status. One nocturnal raptor species widely distributed across the world is the Barn Owl (Tyto alba, Tytonidae). In Chile, this species has been recorded and studied exclusively in rural and sub-urban areas. However, in the city of Valdivia Barn owls exist within the city boundaries. In this study we documented the feeding habits of Barn owls nesting in urban settings of Valdivia, and we analyze the opinions of local neighbors toward the owls. To characterize the diet of owls, we collected all pellets found around their nesting tree on a monthly basis between August 2010 and August 2011. We interviewed the neighbors using a questionnaire that included questions about the utility, ethical or aesthetic value of the owl and the tree where they nested. Our results indicate that the main prey of the Barn Owl was the Long-tailed Colilargo (Oligoryzomys longicaudatus).The neighbors’ perception was favorable to the Barn Owl primarily for aesthetic and ethical reasons, and not utilitarian reasons. Our results suggest that people perception in urban areas is different than in rural areas, where previous studies showed the prevalence of utilitarian values. This positive perception represents a great potential to promote conservation and environmental education in the city, creating a link between people and the natural elements they have in their environment.La percepción que tienen las personas frente a las rapaces está fuertemente infl uenciada por su valor intrínseco, por su utilidad, y por mitos y supersticiones. En particular, las percepciones negativas pueden fomentar la caza furtiva y la persecución de estas aves, afectando su estado de conservación. Una rapaz nocturna distribuida a nivel mundial es la lechuza blanca (Tyto alba, Tytonidae). En Chile, esta especie ha sido registrada y estudiada exclusivamente en zonasrurales y sub-urbanas. Sin embargo, en la ciudad de Valdivia existen lechuzas habitando dentro del perímetro urbano. En este trabajo documentamos la composición de especies de roedores consumidos por las lechuzas blancas dentro de un barrio urbano, y evaluamos la percepción de los vecinos sobre la presencia de lechuza blanca en su barrio. Para caracterizar la dieta de las lechuzas, recolectamos egagrópilas mensualmente entre agosto de 2010 y agosto de 2011. Para conocer la percepción de los vecinos, se elaboró un cuestionario que incluyó preguntas sobre el valor utilitario, ético o estético de la lechuza y del árbol donde nidifi caba. Nuestros resultados indican que la presa más consumida por la lechuza blanca fue el ratón colilarga (Oligoryzomys longicaudatus). La percepción de las personas resultó favorable hacia la lechuza blanca principalmente por razones estéticas y éticas, y no utilitarias. Nuestros resultados sugieren que la percepción de las personas en áreas urbanas es distinta de las zonas rurales, donde trabajos previos han mostrado que prevalecen los valores utilitarios. Esta percepción positiva podría representar un gran potencial para favorecer la conservación y la educación ambiental en la ciudad, generando un vínculo entre las personas y los elementos naturales que poseen en su entorno.&nbsp

    Transgenerational inheritance of environmental information in Caenorhabditis elegans

    Get PDF
    Motivation: In 1906 Luther Burbank, an American botanist, said “Heridity is only the sum of all past environment” (Burbank, 1906). This idea has always been present in spite of being left behind after sustaining that the germline was isolated of the rest of the organism and, therefore, of the environment. With the rediscovery of epigenetics as a regulatory system which controls gene expression without affecting the composition of genes themselves, this idea has regained importance. Not only a great number of cases of environmental changes that influenced the epigenetics in a great variety of species began to be observed; but also the effects of these changes could last for three or more generations. This phenomenon was known as transgenerational epigenetic inheritance (Heard and Martienssen, 2014). This project aims to study the phenomenon of transgenerational epigenetic inheritance in the Caenorhabditis elegans model animal. The idea is to set the parameters where we can identify the phenomenon and reveal the molecular mechanism involved in the process.Methods: We set two different experiments, resistance to pathogen and behavioral respond to the pathogen. For the resistance experiment, plates with Escherichia coli (OP50, main source of nematode's food) and plates with Pseudomonas aeruginosa (PA14, a pathogen) were used to grow mothers and then the percentage of descendants that reach adulthood were scored. For the behavioral experiment, plates with OP50 and plates with both bacteria (PA14 and OP50) were used to grow mothers. Then their eggs were placed on plates containing OP50 and PA14. We counted the percent of worms that went to OP50 and to PA14.Results: It has been observed that individuals whose mothers have been exposed to Pseudomonas aeruginosa are more resistant to it than those whose mothers have never been in contact with the pathogen. On the other hand, it has been observed that this inheritance not only affects the defense mechanisms of the organism, but also influences its behavior. At this time we are studying the genetic pathways involved in this process by using mutants affected in epigenetic and in other candidate pathways.Conclusions: Our results suggest that there is not only an inheritance to stress resistance but also an acquired behavioral inheritance. Genes involved in epigenetic seem to be involved in the process

    Influence of Environmental and Productive Factors on the Biodiversity of Lactic Acid Bacteria Population from Sheep Milk

    Get PDF
    Milk is a typical and satisfactory medium for the growth of lactic acid bacteria (LAB). These microorganisms are of vital importance in the quality of the milk since they contribute to its preservation and give differential organoleptic properties to the final product. Furthermore, LABs can act as biocontrol agents in the dairy industry by inhibiting the growth of undesirable bacteria present in milk and by improving the quality of dairy products such as cheese. In this context, knowing the transfer routes used by LABs from the livestock environment to the milk is of great importance within the dairy industry. Therefore, the objectives of the present study were to expand the knowledge of the LAB population present in the milk of Manchego ewe by means of DNA sequencing techniques and to evaluate the possible transfers of LAB species based on the management of each dairy farm. Samples of bulk tank milk, air (from the milking parlour and from the livestock housing), animal feed and teat surface (taken from 10 sheep per farm) were collected in 12 traditional livestock farms in Castilla-La Mancha (Spain), where each farm presented differences regarding their farming practices. A mixed-effects model was used to evaluate the effects of livestock practices on the distribution of LAB species. Results showed that the vast majority of species identified in the milk had an isolate that was also found in other matrices, which could indicate a microbial transference via the livestock environment to the milk. In addition, the mixed model showed that the factors that positively influence the LAB count were the low-line milking system and the daily use of acid detergent in cleaning the milking machine

    Bodegas, un sitio de pescadores durante el periodo Tardío en el norte del Alto Magdalena - Colombia

    Get PDF
    The results presented below are part of the project entitled “Archaeological study of the impact of pre-Columbian fishing in the area of rapids of the Magdalena River, during the later period (vii to xvi century AD)” Colciencias - Universidad National de Colombia (Bogotá), carriedout by the research group in Archeology and Environment of the Institute of Natural Sciences. This project aimed to approach archaeological issues in the area of influence the Magdalena River rapids. Here, we studied archaeozoological and archaeoichthyological remains, particularly those associated with analysis of landscape units and the cultural contexts provided by the study of ceramics and stone industries. In this study, we present results of our research conducted at the site of Bodegas 1, dated in the xi century ad. The analyzes suggest that the settlement established some houses and orchards on the edge of a mean alluvial terrace located next to the river, where favorable fishing locations exist, particularly of fish species that carry out intense migrations during two annual periods. The changes in the frequencies and the decrease in size of some fish species could be related to the beginning of drier periods that affected their vulnerability.Los resultados que se presentan a continuación forman parte del proyecto titulado “Estudio arqueológico del impacto de la pesca precolombina en la zona de raudales del río Magdalena, durante el periodo Tardío (siglos xi al xii d. C.)” Colciencias - Universidad Nacional de Colombia (Sede Bogotá), desarrollado por el grupo de investigación Arqueología y Ambiente del Instituto de Ciencias Naturales. Este proyecto se propuso abordar la problemática arqueológica del área de influencia de la zona de los raudales del río Magdalena, mediante el estudio de los restos de fauna y, particularmente, de peces migratorios, asociados al análisis de las unidades de paisaje y los contextos culturales que proporcionan el estudio de los materiales cerámicos y de las industrias líticas. Los resultados obtenidos en el sitio de Bodegas 1 indican que fue ocupado por grupos humanos del periodo Tardío en el siglo xi d. C. Los análisis arqueológicos y los estudios de los suelos sugieren que establecieron algunas viviendas y pequeñas huertas sobre el borde de una terraza aluvial media próxima al río, donde se localizan lugares favorables para la pesca, en particular de especies que realizan migraciones intensas durante dos épocas anuales. Los cambios en las frecuencias y la disminución en las tallas de algunas especies de peces podrían estar relacionados con el inicio de periodos más secos que incidieron en su vulnerabilidad

    Understanding ozone generation in electrochemical cells at mild pHs

    Get PDF
    In this work, the production of ozone at mild pH conditions using a commercial electrochemical PEM cell CONDIAPURE Ⓡ is evaluated, at once a phenomenological model is proposed to understand the basis of the processes that occur inside the cell. At these pH conditions, the production of ozone can be explained from the oxidation of water, while the decomposition of ozone is found to be extremely important to explain the global experimental behavior observed. Not only is this decomposition a chemical but also an electrochemically assisted process which, in turn, can be related to the production of other oxidants in the cell which interact with ozone behaving as predators. The model formulated explains and satisfactorily reproduces the influence of the operation mode, the current intensity applied and presence and destruction of organics, with regression coefficients (r2) ranging from 0.88 to 0.99, helping to understand how the production of ozone should be promoted during electrochemical processes

    Is ozone production able to explain the good performance of CabECO® technology in wastewater treatment?

    Get PDF
    This work intends to go a step further in the application of electrochemical technology to produce ozone, by evaluating the production of ozone with a commercial cell registered as CabECO®, which has been previously used to disinfect heavily polluted water in a successful manner, with a view to ascertaining whether this success may be related to the production of ozone. The CabECO® cell is a PEM electrolyzer; that is to say, one in which anode and cathode are connected through a PEM membrane. Since ozone production on the electrolyte is important and depends on the composition of the liquid, attention must be paid to the electrochemical production of scavengers. Dosing of oxygen as microbubbles has a very positive effect on the production of ozone, while temperature regulation is as well considerably important, as the increase in temperature generated by ohmic losses can lead to important decreases in the efficiency of ozone electrogeneration. Rates within the range 0.06–0.60 mg O3 min−1 are observed; this means that the maximum current efficiency reached is as high as 6.11% (considering oxygen as raw matter). These results are extremely promising as compared with other references in the literature, at once they also indicate there is room for further improvements and a long way to prevent the effect of scavengers and increase the efficiency of the process

    Análisis de los servicios de test del VIH de cinco centros comunitarios españoles para la mejora de nuevas estrategias de promoción del diagnóstico precoz

    Get PDF
    Background: In recent years, the number of people tested for HIV has experienced a significant increase. The purpose of this study is to analyze data obtained in Spain in the HIV testing services of five Community Centres members of Agrupación Prueba de VIHda throughout 2014 and 2015,to determine its effectiveness and to characterize the subpopulation with a HIV reactive result. Study design and methods: agrupación Prueba de VIHda performed free, anonymous and confidential HIV tests according to the Consolidated guidelines on HIV testing services of WHO (2015). Data were collected using the questionnaire of the COBATEST network, developed by the COBATEST Project, and its significance was determined statistically. Results: 3061 HIV tests were performed during 2014 and 2015, with a prevalence of reactive results of 2.5%. Heterosexual and bisexual men got tested at older ages than homosexual men and women. Non-Spanish origin seems to be a risk factor for HIV infection within the sample. Bisexual men showed as high prevalence of reactive test as homosexual men, as well as they reported less previous HIV tests. Finally, index testing performed by HIV positive peer educators to the sexual partners of newly diagnosed patients showed higher prevalence than that of the classical Voluntary Counselling and Testing approach outreach most at risk populations. Conclusion:The analysis of the data shows higher prevalence of reactive results in people of non-Spanish origin compared to that of the Spanish subgroup, the former still facing barriers to access the public health system in Spain. It also demonstrates the need of new and adapted approaches for promoting early diagnosis specifically in bisexual men. Index testing by peer HIV positive educators is a highly effective method for testing people at high risk of acquiring HIV infection.Antecedentes: En los últimos años, el número de personas sometidas a pruebas frente al VIH ha experimentado un aumento significativo. El propósito de este estudio es analizar los datos de prevalencia de la infección por VIH obtenidos por cinco centros comunitarios en España pertenecientes a la Agrupación Prueba de VIHda entre 2014 y 2015, determinar su efectividad y caracterizar la subpoblación con un resultado preliminar reactivo. Diseño experimental y métodos: La Agrupación Prueba de VIHda realizó pruebas de VIH gratuitas, anónimas y confidenciales de acuerdo con las directrices consolidadas por la OMS (2015). Los datos fueron recogidos mediante el cuestionario desarrollado por el Proyecto COBATEST y su significación se determinó estadísticamente. Resultados: Durante 2014 y 2015 se realizaron un total de 3061 pruebas frente al VIH, obteniendo una prevalencia de resultados preliminares positivos del 2,5%. Los hombres heterosexuales y bisexuales se realizaron la prueba a edades más avanzadas que los hombres homosexuales y las mujeres. Las personas de origen no español parecieron mostrar un mayor riesgo de infección frente al VIH. Hombres bisexuales mostraron una prevalencia elevada similar a la de hombres homosexuales, así como declararon menos pruebas anteriores frente al VIH. Finalmente, las pruebas realizadas a través de indextesting por los educadores pares de VIH a parejas sexuales de pacientes recién diagnosticados mostraron una prevalencia superior a la obtenida por el modelo tradicional de counselling y testado voluntario ofrecido desde los centros comunitarios a poblaciones de mayor riesgo. Conclusión: El análisis de los datos muestra mayores prevalencias de resultados preliminares reactivos en personas de origen no español comparadas con aquellas del subgrupo de personas españolas, el primero de ellos todavía enfrentando barreras de acceso al sistema sanitario público en España, El análisis también demuestra la necesidad de nuevos enfoques adaptados para promover el diagnóstico precoz especialmente entre hombres bisexuales. Las pruebas realizadas a través de indextesting por educadores pares VIH positivos es un método muy eficaz para el testado de las personas con alto riesgo de contraer la infección por VIH

    Point mutations affecting yeast prion propagation change the structure of its amyloid fibrils

    Get PDF
    We investigated the effect of the point substitutions in the N-terminal domain of the yeast prion protein Sup35 (Sup35NMp) on the structure of its amyloid fibrils. As the objects of the study, proteins with mutations that have different influence on the [PSI+] prion propagation, but do not prevent the aggregation of Sup35NMp in vitro were chosen. The use of the wide range of physico-chemical methods allowed us to show significant differences in the structure of these aggregates, their physical size, clumping tendency. Also we demonstrated that the fluorescent probe thioflavin T (ThT) can be successfully used for investigation of subtle changes in the structural organization of fibrils formed from various Sup35NMp. The obtained results and our theoretical predictions allowed us to conclude that some of selected amino acid substitutions delimit the region of the protein that forms the core of amyloid fibrils, and change the fibrils structure. The relationship of structural features of in vitro Sup35NMp amyloid aggregates with the stability of the [PSI+] prion in vivo allowed us to suggest that oligopeptide repeats (R) of the amyloidogenic N-terminal domain of Sup35NMp from R0 to R2 play a key role in protein aggregation. Their arrangement rather than just presence is critical for propagation of the strong [PSI+] prion variants. The results confirm the suitability of the proposed combination of theoretical and empirical approaches for identifying changes in the amyloid fibrils structure, which, in turn, can significantly affect both the functional stability of amyloid fibrils and their pathogenicity.Laboratorio de Investigación y Desarrollo de Bioactivo

    A 3-Biomarker 2-Point-Based Risk Stratification Strategy in Acute Heart Failure

    Get PDF
    Altres ajuts: ISCIII/RD06-0003-0000Altres ajuts: ISCIII/RD12/0042/0002Introduction and Objectives: Most multi-biomarker strategies in acute heart failure (HF) have only measured biomarkers in a single-point time. This study aimed to evaluate the prognostic yielding of NT-proBNP, hsTnT, Cys-C, hs-CRP, GDF15, and GAL-3 in HF patients both at admission and discharge. Methods: We included 830 patients enrolled consecutively in a prospective multicenter registry. Primary outcome was 12-month mortality. The gain in the C-index, calibration, net reclassification improvement (NRI), and integrated discrimination improvement (IDI) was calculated after adding each individual biomarker value or their combination on top of the best clinical model developed in this study (C-index 0.752, 0.715-0.789) and also on top of 4 currently used scores (MAGGIC, GWTG-HF, Redin-SCORE, BCN-bioHF). Results: After 12-month, death occurred in 154 (18.5%) cases. On top of the best clinical model, the addition of NT-proBNP, hs-CRP, and GDF-15 above the respective cutoff point at admission and discharge and their delta during compensation improved the C-index to 0.782 (0.747-0.817), IDI by 5% (p < 0.001), and NRI by 57% (p < 0.001) for 12-month mortality. A 4-risk grading categories for 12-month mortality (11.7, 19.2, 26.7, and 39.4%, respectively; p < 0.001) were obtained using combination of these biomarkers. Conclusion: A model including NT-proBNP, hs-CRP, and GDF-15 measured at admission and discharge afforded a mortality risk prediction greater than our clinical model and also better than the most currently used scores. In addition, this 3-biomarker panel defined 4-risk categories for 12-month mortality
    corecore