173 research outputs found

    Phylogenetic studies of newly isolated freshwater Magnetospirilla using cbb and mam genes

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    The phylogeny and general relatedness of prokaryotes is determined by comparisons of the sequences of rRNA genes, most commonly the 16S rRNA gene. Comparisons between other gene sequences have been used for this purpose and some have supported conclusions from 16S rRNA genes while others have not. In this study, 13 new magnetospirilla were phylogenetically characterized using the sequences of the 16S rRNA gene as well as the genes for forms I and II ribulose-1,5-bisphosphate carboxylase/oxygenase (RubisCO) (cbbL and cbbM, respectively) and for two magnetosome membrane proteins unique to magnetotactic bacteria, mamJ and mamK. Polymerase chain reaction (PCR) with degenerate primers designed for the specific genes under study was used to amplify a large portion of the genes. PCR products were cloned and sequenced and used for the construction of phylogenetic trees. Based on 16S rRNA gene sequences, the magnetospirilla phylogenetically span, more as a continuum rather than as clearly delineated groups, over two genera based on the current accepted sequence divergence between organisms for genera (\u3e5%). While almost all strains appear to fit into the genus Magnetospirillum, strain LM-1 appears to represent a new genus. Phylogeny of these strains based on cbbM sequences was reasonably consistent with that from 16S rRNA genes. The cbbL gene was not a good choice for this study as most strains did not possess this gene. Relatedness and phylogeny of the strains based on mamJ and mamK sequences was more complex. Although our data set is not complete, some specific strains shown to be closely related by 16S rRNA gene sequence, also appeared to be closely related based on one or both of the mam gene sequences (e.g., strains UT-1, LM-2 and M. gryphiswaldense strain MSR-1). Other strains did not show this type of relationship. Because of these somewhat inconsistent results, those from mam gene sequences might reflect evolution of the magnetosome gene island (MAI) in magnetospirilla rather than relatedness between strains

    Parasitism of Corn Earworm, Helicoverpa zea (Boddie) (Lepidoptera: Noctuidae), by Tachinid Flies in Cultivated Hemp

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    In a survey on hemp grown in western Kentucky we found an average of 27.8 CEW larvae per plant. We recorded 45% parasitism of CEW in these fields by two species of tachinid flies, Winthemia rufopicta and Lespesia aletiae. Most parasitized larvae were third to sixth instars at the time of collection. We found up to 22 tachinid eggs per host larva, 89% of which typically bore between 1 and 5 eggs on the thorax. 45.9% of CEW bearing eggs died. The number of tachinid eggs per host was unrelated to host body mass, but both the number of tachinid eggs and caterpillar body mass influenced CEW survival. Larger CEW often survived parasitism and the number of fly eggs was negatively related to survival rate. The emergence of adult flies was positively correlated with the number of eggs, but no influence of the host size was found. High mortality of CEW larvae and the parasitoids developing within them in this system suggests that secondary chemicals (or poor nutrition) of the hemp diet may be negatively affecting host and parasitoid development and influencing their interactions

    Comparison of bioinspired algorithms applied to the timetabling problem

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    The problem of timetabling events is present in various organizations such as schools, hospitals, transportation centers. The purpose of timetabling activities at a university is to ensure that all students attend their required subjects in accordance with the available resources. The set of constraints that must be considered in the design of timetables involves students, teachers and infrastructure. This study shows that acceptable solutions are generated through the application of genetic, memetic and immune system algorithms for the problem of timetabling. The algorithms are applied to real instances of the University of Mumbai in India and their results are comparable with those of a human expert

    Frecuencia de lesiones macroscópicas en pulmones de bovinos tipo exportación faenados en el frigorífico del municipio de Montería, Colombia

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    Durante el presente estudio se evaluaron los pulmones de 582 bovinos machos tipo exportación, de razas cebuinas  y diferentes procedencias, faenados en el frigorífico del municipio de  Montería – Córdoba (FRIGOSINU), con la finalidad de identificar las lesiones encontradas en este órgano. El muestreo se hizo en forma sistemática durante 10 días, evaluando animales escogidos al azar. Durante el tiempo de estudio se decomisaron los pulmones de 190 animales con algún tipo de alteración pulmonar, lo cual corresponde al 32,6%. El 67,4% de los animales muestreados resultaron sin alteración macroscópica evidente. Estos resultados se analizaron mediante estadística descriptiva, encontrándose que el enfisema intersticial fue la causa principal de decomiso, siendo observado en el 64,7% de los animales, seguido de hemorragias (15,8%), neumonía lobar (10,5%), congestión pulmonar (8,9%) y broncoaspiración de contenido ruminal (9,0%). Al analizar las evidencias macroscópicas de los pulmones decomisados, se concluye que la mayoría de las alteraciones encontradas en los pulmones decomisados obedece a fallas en el proceso de insensibilización y sacrificio de los animales, no se pueden descartar problemas infecciosos, sin embargo el diagnóstico de laboratoriao  no fue contemplado en este estudio, por lo tanto se establece diagnóstico presuntivo de acuerdo a las lesiones macroscópicas

    Approach for the classification of polliniferous vegetation using multispectral imaging and neural networks

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    Beekeeping has suffered a serious deterioration in the regions of the world. The possibility of nectar-polliniferous resources has decreased and, therefore, the feeding of bees, with the consequent decrease in production. There is, therefore, a need to improve marketing and diversification systems and to update production techniques and the management of the production process by beekeepers to obtain the quality of honey required by the market [1]. This work proposes the use of spectral information to identify the different pollen-producing plants using remote vision, image processing, and artificial neural networks

    Information consumption patterns from big data

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    Virtual social networks imply an important opportunity to generate friendlier communication bridges between students, teachers and other actors related to the educational field. In this sense, our study presents an approximation to the connection habits between university students in these networks, which in the future will allow to take advantage of these platforms to achieve a successful communication between actors. Thus, the characterization of uses, habits and consumption of virtual social networks becomes very relevant

    Management system for optimizing public transport networks: GPS record

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    As cities continue to grow in size and population, the design of public transport networks becomes complicated, given the wide diversity in the origins and destinations of users [1], as well as the saturation of vehicle infrastructure in large cities despite their attempts to adapt it according to population distribution. This indicates that, in order to reduce users’ travel time, it is necessary to implement alternative road solutions to the use of cars, increasing investment in public transportation [2, 3] by conducting a comprehensive analysis of the state of transportation. This situation has made appear the solutions and development oriented to transportation based on Internet of Things (IoT) which allows, in a first stage, monitoring of public transport systems, in order to optimize the deployment of transport units and thus reduce the time of transfer of users through the cities [4]. These solution proposals are focused on information collected from user resources (data collected through smart phones) to create a common database [5]. The present study proposes the development of an intelligent monitoring and management system for public transportation networks using a hybrid communication architecture based on wireless node networks using IPv6 and cellular networks (LTE, LTE-M)

    The Modernization of the Autopsy: Application of Ultrastructural and Biochemical Methods to Human Disease

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    The autopsy has provided, and still provides, the stimulus for many attempts to reproduce disease in experimental animal models. This approach has become increasingly difficult, however, in the case of human disease, principally shock. The study of some pathological states in animal models requires testing in several species and final confirmation in man before this knowledge can be applied to living patients. In our studies the application of cell biology techniques at autopsy has permitted the generation of new hypotheses which are more amenable to further exploration in experimental models and can be more precisely related to human disease

    Mechanical and durability properties of recycled aggregate concrete with ternary binder system and optimized mix proportion

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    tThis study aimed to investigate the mechanical and durability properties of recycled aggre-gate concrete with a ternary binder system and optimized mix proportion. Two concretebatches were developed using a densified mix design approach (DMDA) to evaluate therequired mix proportions. Batch I have GGBS content varied at 0%, 10%, 20%, 30%, 40% and50% at constant w/b ratio of 0.45, while batch II concrete mix have varied water/binder ratios:0.3, 0.35, 0.4, 0.45 and 0.5 at constant GGBS replacement level of 30%. The fine aggregate(river sand) of the two batches was blended with fly ash at optimum loose packing density(FA + Sand) and superplasticizer (SP) was incorporated in the mix at a constant level of 1.4%.A control mix comprising of natural aggregate was also developed. The results obtainedshowcased the feasibility of producing structural concrete with recycled aggregates usingGGBS and fly ash. The mechanical and durability properties were best at 30% GGBS content and 0.35 water/binder ratio. The DMDA for mix proportion adopted for RAC contributed sig-nificantly to improving its properties when compared to NAC, especially at the optimumobserved RAC mix with compressive strength of 52 MPa. Also, the mix demonstrated goodpermeability resistance in terms of chloride-ion ingress and capillary water absorption
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