180 research outputs found
Challenges of Navigational Queries: Finding Best Paths in Graphs
Life science sources are characterized by a complex graph of overlapping sources, and multiple alternate links between sources.
A (navigational) query may be answered by traversing multiple alternate paths between an origin and target source. Paths may be characterized by several metrics, including the cardinality of objects of the target source(TOC), the cost of query evaluation of a plan for the path, and the user's preference for specific paths. Our challenge is finding the best paths among the set of
all solutions, AllPaths, that meet some user specified ranking criteria. If the user ranking criteria is strict, then the problem
is to find the Top K paths. If the user wants a trade-off of several metrics, then the problem is to find the Skyline paths that are not dominated by other paths. {\em NSearch} is a naive solution. {\em BFSrchOpt} is a heuristic best-first search strategy. It uses a metric to rank partial solutions (subpaths) and (local) metrics to guide graph traversal, and produces BFPaths. We compare the precision and recall of BFPaths compared to the Top K\% or Skyline of AllPaths.
We study the impact of graph properties on the behavior of {\em BFSrchOpt}. {\em BFSrchOpt} can be orders of magnitude faster than {\em NSearch}
Molecular identification of six species of Calliphoridae (Diptera) with forensic interest in Bogotá, Colombia
Taxonomic identification of the species involved in the processes of cadaveric decomposition is a fundamental procedure in forensic entomological analysis. Among the species involved in the processes of decay, those of the Calliphoridae family are particularly important because they come to the body in the early stages of decomposition. The aim of this research is to identify six species of Calliphoridae (Calliphora nigribasis, Calliphora vicina, Compsomyopsis verena, Sarconesiopsis magellanica, Chrysomia albiceps and Roraimomusca roraima) with forensic interest found in Bogotá. For that, sequences of 599 bp from mitochondrial gene COII wereas obtained. The identification was made by analysis of genetic distances under Jukes-Cantor model. The results showed levels of interspecific distances greater than 3.7%, while intraspecifics levels does not exceed 2.3%. The genetic distances obtained were used to construct a phenogram under the Maximum Likelihood model and the topology of that tree agrees with the current taxonomic organization for the family Calliphoridae family
Prevalencia de enteroparasitosis en ninos que asisten a colegios basicos municipalizados en la Ciudad de Talca.
38 p.Con la finalidad de educar e informar y de alguna manera como futuros profesionales del área de la salud, contribuir de cierta modo en el diario vivir de las familias en estudio a mejorar las condiciones higiénicas, por supuesto de salud , conducta y rendimiento escolar en los establecimientos de educación básica de escasos recursos de la Ciudad de Talca, se planteo este estudio de prevalencia de enteroparasitosis enmarcado en el aporte a la ciudadanía y al
proyecto de tesis para la obtención del grado de Licenciado en Tecnología Médica de la Universidad de Talca. Se trazó inicialmente una etapa informativa y educativa a los apoderados y cuerpo docente de los establecimientos donde
se realizaría el estudio, esto con el fin de informar sobre los efectos adversos que presentan estas infecciones en los alumnos e hijos. Con este estudio se espera disminuir las tasas de prevalencia de parasitismo en los centros educacionales donde la transmisión de estas infecciones es mayor debido a las
condiciones de hacinamiento y contacto entre los alumnos. Además este estudio se realiza con el fin de ser un aporte a las pocas investigaciones
realizados en la región del Maule y por supuesto a ayudar a sectores donde el desconocimiento de este tipo de infecciones y 1a posibilidad de diagnostico y tratamiento es limitado. El control de las enteroparasitosis debe formar parte de las políticas de control sanitario y ambiental del entorno educacional y familiar del alumno
New kinematic models for Pacific‐North America Motion from 3 Ma to Present, II: Evidence for a “Baja California Shear Zone”
We use new models for present‐day Pacific‐North America motion to evaluate the tectonics of offshore regions west of the Californias. Vandenburg in coastal Alta California moves at the Pacific plate velocity within uncertainties (∼1 mm/yr) after correcting for strain accumulation on the San Andreas and San Gregorio‐Hosgri faults with a model that includes a viscoelastic lower crust. Modeled and measured velocities at coastal sites in Baja California south of the Agua Blanca fault, a region that most previous models consider Pacific plate, differ by 3–8 mm/yr, with coastal sites moving slower that the Pacific plate. We interpret these discrepancies in terms of strain accumulation on known on‐shore faults, combined with right lateral slip at a rate of 3–4 mm/yr on additional faults offshore peninsular Baja California in the Pacific. Offshore seismicity, offset Quaternary features along the west coast of Baja California, and a discrepancy between the magnetically determined spreading rate in the Gulf Rise and the total plate rate from a geological model provide independent evidence for a “Baja California shear zone.
Adipose tissue transcriptome reflects variations between subjects with continued weight loss and subjects regaining weight 6 mo after caloric restriction independent of energy intake
BACKGROUND:
The mechanisms underlying body weight evolution after diet-induced weight loss are poorly understood.
OBJECTIVE:
We aimed to identify and characterize differences in the subcutaneous adipose tissue (SAT) transcriptome of subjects with different weight changes after energy restriction-induced weight loss during 6 mo on 4 different diets.
DESIGN:
After an 8-wk low-calorie diet (800 kcal/d), we randomly assigned weight-reduced obese subjects from 8 European countries to receive 4 diets that differed in protein and glycemic index content. In addition to anthropometric and plasma markers, SAT biopsies were taken at the beginning [clinical investigation day (CID) 2] and end (CID3) of the weight follow-up period. Microarray analysis was used to define SAT gene expression profiles at CID2 and CID3 in 22 women with continued weight loss (successful group) and in 22 women with weight regain (unsuccessful group) across the 4 dietary arms.
RESULTS:
Differences in SAT gene expression patterns between successful and unsuccessful groups were mainly due to weight variations rather than to differences in dietary macronutrient content. An analysis of covariance with total energy intake as a covariate identified 1338 differentially expressed genes. Cellular growth and proliferation, cell death, cellular function, and maintenance were the main biological processes represented in SAT from subjects who regained weight. Mitochondrial oxidative phosphorylation was the major pattern associated with continued weight loss.
CONCLUSIONS:
The ability to control body weight loss independent of energy intake or diet composition is reflected in the SAT transcriptome. Although cell proliferation may be detrimental, a greater mitochondrial energy gene expression is suggested as being beneficial for weight control
MicroRNA: an Emerging Therapeutic Target and Intervention Tool
MicroRNAs (miRNAs) are a class of short non-coding RNAs with posttranscriptional regulatory functions. To date, more than 600 human miRNAs have been experimentally identified, and estimated to regulate more than one third of cellular messenger RNAs. Accumulating evidence has linked the dysregulated expression patterns of miRNAs to a variety of diseases, such as cancer, neurodegenerative diseases, cardiovascular diseases and viral infections. MiRNAs provide its particular layer of network for gene regulation, thus possessing the great potential both as a novel class of therapeutic targets and as a powerful intervention tool. In this regard, synthetic RNAs that contain the binding sites of miRNA have been shown to work as a “decoy” or “miRNA sponge” to inhibit the function of specific miRNAs. On the other hand, miRNA expression vectors have been used to restore or overexpress specific miRNAs to achieve a long-term effect. Further, double-stranded miRNA mimetics for transient replacement have been experimentally validated. Endogenous precursor miRNAs have also been used as scaffolds for the induction of RNA interference. This article reviews the recent progress on this emerging technology as a powerful tool for gene regulation studies and particularly as a rationale strategy for design of therapeutics
Herramienta integral y de bajo coste para el desarrollo de prácticas remotas para las asignaturas de Ciencias e Ingeniería
Los laboratorios remotos, en los que los alumnos interactúan con los dispositivos reales a través de Internet, incrementa el tiempo de uso de dichos dispositivos por parte de los alumnos y el número de pruebas que pueden realizar durante las experiencias. Sin embargo, para implementarlos, los docentes habitualmente tienen que saber utilizar una serie de tecnologías diferentes, que dificultan su puesta en marcha y mantenimiento.
Para paliar estos problemas, en este Proyecto de Innovación y Mejora de la Calidad Docente (PIMCD) se ha desarrollado una nueva metodología desde la que se centraliza la puesta en marcha de todo el laboratorio desde una única herramienta (Easy JavaScript Simulations, EJsS), que sirve tanto para gestionar el código mediante el que se interactúa con los dispositivos, el servidor que da acceso remoto a la práctica, y la interfaz gráfica con la que los alumnos interactúan con los dispositivos. Además, es importante resaltar que es una metodología de bajo coste, ya que desde el punto de vista del proceso de conversión de un laboratorio presencial ya existente en uno remoto, solo necesita una Raspberry PI para desplegar todo el software del laboratorio.
Además, en este proyecto también se presentan un conjunto de experiencias desarrolladas con las mismas, que ya están siendo utilizadas por los alumnos en diferentes asignaturas de Ingeniería Electrónica de Comunicaciones y un nuevo laboratorio remoto de Robótica que se pondrá en marcha el curso que viene
Regulation of connexin- and pannexin-based channels by post-translational modifications
Connexin (Cx) and pannexin (Panx) proteins form large conductance channels, which function as regulators of communication between neighbouring cells via gap junctions and/or hemichannels. Intercellular communication is essential to coordinate cellular responses in tissues and organs, thereby fulfilling an essential role in the spreading of signalling, survival and death processes. The functional properties of gap junctions and hemichannels are modulated by different physiological and pathophysiological stimuli. At the molecular level, Cxs and Panxs function as multi-protein channel complexes, regulating their channel localisation and activity. In addition to this, gap junctional channels and hemichannels are modulated by different post-translational modifications (PTMs), including phosphorylation, glycosylation, proteolysis, N-acetylation, S-nitrosylation, ubiquitination, lipidation, hydroxylation, methylation and deamidation. These PTMs influence almost all aspects of communicating junctional channels in normal cell biology and pathophysiology. In this review, we will provide a systematic overview of PTMs of communicating junction proteins and discuss their effects on Cx and Panx-channel activity and localisation
X chromosome inactivation does not necessarily determine the severity of the phenotype in Rett syndrome patients
Rett syndrome (RTT) is a severe neurological disorder usually caused by mutations in the MECP2 gene. Since the MECP2 gene is located on the X chromosome, X chromosome inactivation (XCI) could play a role in the wide range of phenotypic variation of RTT patients; however, classical methylation-based protocols to evaluate XCI could not determine whether the preferentially inactivated X chromosome carried the mutant or the wild-type allele. Therefore, we developed an allele-specific methylation-based assay to evaluate methylation at the loci of several recurrent MECP2 mutations. We analyzed the XCI patterns in the blood of 174 RTT patients, but we did not find a clear correlation between XCI and the clinical presentation. We also compared XCI in blood and brain cortex samples of two patients and found differences between XCI patterns in these tissues. However, RTT mainly being a neurological disease complicates the establishment of a correlation between the XCI in blood and the clinical presentation of the patients. Furthermore, we analyzed MECP2 transcript levels and found differences from the expected levels according to XCI. Many factors other than XCI could affect the RTT phenotype, which in combination could influence the clinical presentation of RTT patients to a greater extent than slight variations in the XCI pattern
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