Wireless Optical Communications for Intra-Spacecraft Networks Based on OCDMA with Random Optical Codes

In recent years, spacial agencies have shown a growing interest in optical wireless as an alternative to wired and radio-frequency communications. The use of these techniques for intra-spacecraft communications reduces the effect of take-off acceleration and vibrations on the systems by avoiding the need for rugged connectors and provides a significant mass reduction. Diffuse transmission also eases the design process as terminals can be placed almost anywhere without a tight planification to ensure the proper system behaviour. Previous studies have compared the performance of radio-frequency and infrared optical communications. In an intra-satellite environment optical techniques help reduce EMI related problems, and their main disadvantages - multipath dispersion and the need for line-of-sight - can be neglected due to the reduced cavity size. Channel studies demonstrate that the effect of the channel can be neglected in small environments if data bandwidth is lower than some hundreds of MHz

Evaluación de filtración y efectividad de dos selladores endodónticos ante la inoculación de enterococcus faecalis.

El éxito del tratamiento de conductos depende de: asepsia, preparación biomecánica y sellado apical. El cemento biocerámico de silicato tricálcico BioRoot™ RCS “forma una unión química con la dentina y provoca menos filtración”; el AHPlus®, a base de resina epóxica, tiene estabilidad y adecuado sellado

Clustering and beamforming for efficient communication in wireless sensor networks

Energy efficiency is a critical issue for wireless sensor networks (WSNs) as sensor nodes have limited power availability. In order to address this issue, this paper tries to maximize the power efficiency in WSNs by means of the evaluation of WSN node networks and their performance when both clustering and antenna beamforming techniques are applied. In this work, four different scenarios are defined, each one considering different numbers of sensors: 50, 20, 10, five, and two nodes per scenario, and each scenario is randomly generated thirty times in order to statistically validate the results. For each experiment, two different target directions for transmission are taken into consideration in the optimization process (ɸ = 0º and Ɵ = 45º; ɸ = 45º, and Ɵ = 45º). Each scenario is evaluated for two different types of antennas, an ideal isotropic antenna and a conventional dipole one. In this set of experiments two types of WSN are evaluated: in the first one, all of the sensors have the same amount of power for communications purposes; in the second one, each sensor has a different amount of power for its communications purposes. The analyzed cases in this document are focused on 2D surface and 3D space for the node location. To the authors’ knowledge, this is the first time that beamforming and clustering are simultaneously applied to increase the network lifetime in WSNs.Gobierno de Extremadura y Fondos FEDER: Proyecto IB13113peerReviewe

Análisis histológico de un tratamiento de conductos realizado hace 40 años: reporte de un caso

El éxito del tratamiento se logra cumpliendo múltiples factores: el diagnóstico pulpar y periapical, adecuado aislamiento que permita trabajar en un campo operatorio desinfectado evitando contaminación externa, adecuada instrumentación, desinfección y obturación de los conductos radiculares.Además de estos factores, existe la gran controversia de la importancia que la restauración coronaria postendodóntica tiene en el pronóstico del tratamiento de conductos a largo plazo.Este trabajo muestra los resultados de un estudio histológico de un tratamiento de conductos realizado de forma aséptica, hace 40 años, donde el organismo fue capaz de mantener el tejido pulpar apical vivo y libre de inflamación, a pesar de la fractura de la restauración coronaria que fue la principal causa de fracaso

DISEÑO E IMPLEMENTACIÓN DE UN INVERSOR ACÚSTICO COMO APOYO DIDÁCTICO EN LA ENSEÑANZA DE LA ELECTRÓNICA DE POTENCIA (DESIGN AND IMPLEMENTATION OF AN ACOUSTIC INVERTER AS DIDACTIC SUPPORT IN THE TEACHING OF POWER ELECTRONICS)

Resumen   Actualmente los sistemas de conversión de corriente directa a corriente alternan, (denominados comúnmente inversores u onduladores) han tenido una relevancia importante, esto debido a las aplicaciones que se le está dando en sistemas eólicos, fotovoltaicos y automóviles eléctricos, por mencionar solo algunos. Debido a lo anterior, resulta indispensable que los alumnos de las ingenierías mecatrónica y electrónica comprendan cada una de las etapas que conforman un inversor.Este artículo muestra el diseño e implementación de un inversor que sirva de apoyo en las materias de “electrónica de potencia aplicada” y de “electrónica de potencia” que se imparten a los alumnos de las ingenierías mecatrónica y electrónica respectivamente; cabe resaltar que, con el fin de hacerlo llamativo para el estudiante, el inversor es acústico, siendo capaz de generar tres notas del sistema temperado (C, D y E en la cuarta octava), las cuales se pueden escuchar por medio de una bocina en la salida de dicho inversor.Palabra(s) Clave: Electrónica de potencia, Inversor, sistema de conversión. Abstract   Currently, the direct to alternate current conversion systems, (commonly called inverters) have had an important relevance due to the applications that it is being given in wind systems, photovoltaic and electric cars, to mention just a few. Due to the above, it is essential that the students of the mechatronics and electronics engineering understand each of the stages that conform an inverter.This paper shows the design and implementation of an inverter that serves as educational support in the subjects of “applied power electronics” and “power electronics” that are taught to students of mechatronics and electronics engineering respectively; It should be noted that, in order to make it attractive for the student, the inverter is acoustic, being able to generate three notes of tempered system (C, D, and E in the fourth octave), which can be heard through a speaker in the output of the inverter.Keywords: Conversion system,inverter, power electronics

CURSO SOBRE EXPLICACIÓN LINGÜÍSTICA VINCULADA A ESTEREOTIPOS METODOLÓGICOS EN LA REDACCIÓN CIENTÍFICA DE PROFESIONALES UNIVERSITARIOS

There is acceptance and establishment of methodological stereotypes by professionals at the University of Medical Sciences of Villa Clara, Cuba. This is due to theoretical ignorance about the interrelation of linguistics with the methodology of research in the conscious expression of scientifi c language. Th e situation has served as a motivation to these authors to reverse it through the design and development of a course aimed at these university students. The essence of the course lies in the linguistic explanation –applied linguistics–, linked to methodological stereotypes in scientifi c writing. However, in parallel with the teaching process, a study was conducted to perceive possible conceptual changes in students. Hence, the objective of: is research is to expose the experience and educational-research results inherent to the referred course. Methodologically, the heuristic proceedings of language teaching, as well as the literary analysis in the study of the language fi gured in diff erent styles were used for teaching. In the investigative process, the theoretical methods- synthesis and induction-deduction were used to obtain, process, and analyze the information. Empirical methods of observation and documentary review were also used, in order to obtain the primary data of the diagnosis, as well as the final data derived from the evaluation and of a survey applied when completing the course. The mathematical method of percentage analysis served to tabulate and process the information obtained. As for the results, a conceptual change in students may be found from the diagnosis; phase where these did not notice the relationship between methodological patterns and linguistic science. By completing the course, the students proved to be aware of that interrelation. Finally, the authors consider that the greatest significance of the course lies in the reflection, discussion, and analysis of facts sometimes unnoticed by the professionals of science; evidently, a marked purpose is to move static and dogmatic thought through reasons argued and shared, in this case, by the generality of the group.Existe aceptación y establecimiento de estereotipos metodológicos por parte de los profesionales de la Universidad de Ciencias Médicas de Villa Clara, Cuba. Ello se debe al desconocimiento teórico acerca de la interrelación de la lingüística con la metodología de la investigación en la expresión consciente del lenguaje científico. La situación ha servido como motivación a estos autores para revertirla mediante el diseño y desarrollo de un posgrado dirigido a dichos universitarios. La esencia del curso radica en la explicación lingüística –lingüística aplicada–, vinculada a estereotipos metodológicos en la redacción científica. No obstante, paralelamente al proceso docente, se realizó un estudio para percibir los posibles cambios conceptuales en los cursistas. De ahí, el objetivo: exponer la experiencia y resultados docente-investigativos inherentes al curso referido. Metodológicamente, se emplearon para la docencia los procedimientos heurísticos propios de la enseñanza de la lengua, así como el análisis literario en el estudio del lenguaje figurado en diferentes estilos. En el proceso investigativo se utilizaron fundamentalmente los métodos teóricos análisis-síntesis e inducción-deducción para obtener, procesar y analizar la información. También se emplearon los métodos empíricos de observación y revisión documental, con el fin de obtener los datos primarios del diagnóstico, así como los datos finales derivados de la evaluación y de una encuesta aplicada al culminar el curso. El método matemático de análisis porcentual sirvió para tabular y procesar la información obtenida. En cuanto a los resultados, se pudo constatar un cambio conceptual en los cursistas a partir del diagnóstico; fase donde estos no se percataban de la relación entre los patrones metodológicos y la ciencia lingüística. Al culminar el posgrado, los alumnos demostraron estar conscientes de dicha interrelación. Finalmente, los autores consideran que la mayor significación del curso radica en la reflexión, la discusión y el análisis de hechos a veces inadvertidos por los profesionales de la ciencia; evidentemente, un propósito marcado es mover el pensamiento estático y dogmático mediante razones argumentadas y compartidas, en este caso, por la generalidad del grupo

Comprehensive establishment and characterization of orthoxenograft mouse models of malignant peripheral nerve sheath tumors for personalized medicine

Malignant peripheral nerve sheath tumors (MPNSTs) are soft-tissue sarcomas that can arise either sporadically or in association with neurofibromatosis type 1 (NF1). These aggressive malignancies confer poor survival, with no effective therapy available. We present the generation and characterization of five distinct MPNST orthoxenograft models for preclinical testing and personalized medicine. Four of the models are patient-derived tumor xenografts (PDTX), two independent MPNSTs from the same NF1 patient and two from different sporadic patients. The fifth model is an orthoxenograft derived from an NF1-related MPNST cell line. All MPNST orthoxenografts were generated by tumor implantation, or cell line injection, next to the sciatic nerve of nude mice, and were perpetuated by 7-10 mouse-to-mouse passages. The models reliably recapitulate the histopathological properties of their parental primary tumors. They also mimic distal dissemination properties in mice. Human stroma was rapidly lost after MPNST engraftment and replaced by murine stroma, which facilitated genomic tumor characterization. Compatible with an origin in a catastrophic event and subsequent genome stabilization, MPNST contained highly altered genomes that remained remarkably stable in orthoxenograft establishment and along passages. Mutational frequency and type of somatic point mutations were highly variable among the different MPNSTs modeled, but very consistent when comparing primary tumors with matched orthoxenografts generated. Unsupervised cluster analysis and principal component analysis (PCA) using an MPNST expression signature of ~1,000 genes grouped together all primary tumor-orthoxenograft pairs. Our work points to differences in the engraftment process of primary tumors compared with the engraftment of established cell lines. Following standardization and extensive characterization and validation, the orthoxenograft models were used for initial preclinical drug testing. Sorafenib (a BRAF inhibitor), in combination with doxorubicin or rapamycin, was found to be the most effective treatment for reducing MPNST growth. The development of genomically well-characterized preclinical models for MPNST allowed the evaluation of novel therapeutic strategies for personalized medicine

Comprehensive establishment and characterization of orthoxenograft mouse models of malignant peripheral nerve sheath tumors for personalized medicine

Malignant peripheral nerve sheath tumors (MPNSTs) are soft-tissue sarcomas that can arise either sporadically or in association with neurofibromatosis type 1 (NF1). These aggressive malignancies confer poor survival, with no effective therapy available. We present the generation and characterization of five distinct MPNST orthoxenograft models for preclinical testing and personalized medicine. Four of the models are patient-derived tumor xenografts (PDTX), two independent MPNSTs from the same NF1 patient and two from different sporadic patients. The fifth model is an orthoxenograft derived from an NF1-related MPNST cell line. All MPNST orthoxenografts were generated by tumor implantation, or cell line injection, next to the sciatic nerve of nude mice, and were perpetuated by 7-10 mouse-to-mouse passages. The models reliably recapitulate the histopathological properties of their parental primary tumors. They also mimic distal dissemination properties in mice. Human stroma was rapidly lost after MPNST engraftment and replaced by murine stroma, which facilitated genomic tumor characterization. Compatible with an origin in a catastrophic event and subsequent genome stabilization, MPNST contained highly altered genomes that remained remarkably stable in orthoxenograft establishment and along passages. Mutational frequency and type of somatic point mutations were highly variable among the different MPNSTs modeled, but very consistent when comparing primary tumors with matched orthoxenografts generated. Unsupervised cluster analysis and principal component analysis (PCA) using an MPNST expression signature of ~1,000 genes grouped together all primary tumor-orthoxenograft pairs. Our work points to differences in the engraftment process of primary tumors compared with the engraftment of established cell lines. Following standardization and extensive characterization and validation, the orthoxenograft models were used for initial preclinical drug testing. Sorafenib (a BRAF inhibitor), in combination with doxorubicin or rapamycin, was found to be the most effective treatment for reducing MPNST growth. The development of genomically well-characterized preclinical models for MPNST allowed the evaluation of novel therapeutic strategies for personalized medicine

High-throughput sequencing of the 16S rRNA gene to analyze the gut microbiome in juvenile and adult tropical gar (Atractosteus tropicus)

Tropical gar (Atractosteus tropicus) is freshwater and estuarine fish, inhabiting the Earth since the Mesozoic era and undergoing limited physiological variation ever since. Besides its recognized cultural and scientific relevance, the species has seen remarkable growth in its economic impact due to pisciculture. In this study, we present the first report of the whole taxonomic composition of microbial communities in gut contents in juveniles and adults of A. tropicus, by sex and origin (wild and cultivated). For this study, 508 genera were identified, with the most and least abundant being Cetobacterium and Paludibacter, respectively. Fusobacteria, Proteobacteria, Firmicutes, and Bacteroidetes phyla are the core gut microbiome of A. tropicus juvenile and adult by sex and origin. Deinococcus-Thermus phylum sequence was only identified in wild-type males. In the phylogenetic trees reconstruction Lactococcus lactis strains CAU929 and CAU6600, Cp6 and CAU9951, Cetobacterium strain H69, Aeromonas hydrophila strain P5 and WR-5-3-2, Aeromonas sobria strain CP DC28 and Aeromonas hydrophila were identified, some of them with probiotic potential within the three dominant phyla in core gut microbiome in A. tropicus adults, especially in wild-type organisms. Myroides genus was recognized in microbiota gut of the cultivated juvenile A. tropicus. Nevertheless, Alpha diversity indicated that the highest gut microbiota abundance and richness is found in cultivated juvenile and wild-type adult A. tropicus female, rather than adult wild-type males and the least gut microbiota abundance and richness is found in a cultivated adult of A. tropicus for both sexes.The authors thank the Mexican National Council of Science and Technology for the postgraduate studies thesis scholarship and the mixed scholarship granted to carry out the research internship at the University of Valencia (Spain). This research received external funding from the Mexican National Council of Science and Technology "Strengthening of the Master's Degree in Environmental Sciences for its Permanence in the National Register of Quality Graduates of CONACYT" Reg. No. TAB-2014-C29-245836 and the Project "Estudio de la fisiología digestiva en larvas y juveniles de pejelagarto (Atractosteus tropicus) con base en técnicas histológicas, bioquímicas y moleculares" Reg. No. CB-2016-01-282765.Peer reviewe

Evidence for association between structural variants in lissencephaly-related genes and executive deficits in schizophrenia or bipolar patients from a Spanish isolate population

There is evidence for an association between structural variants in genes for lissencephaly, which are involved in neuronal migration, and prefrontal cognitive deficits in schizophrenia and bipolar patients. On the basis of these intriguing findings, we analyzed 16 markers located in the lissencephaly critical region (LCR in chromosome 17p13.3) in 124 schizophrenic, 56 bipolar, and 141 healthy individuals. All recruits were from a Spanish population isolate of Basque origin that is characterized by low genetic heterogeneity. In addition, we examined whether structural genomic variations in the LCR were associated with executive cognition. Twenty-three patients (12.8%), but none of the controls, showed structural variants (deletions and insertions) in either of two markers related with lissencephaly (D17S1566 on tumor suppressor gene TP53: tumor protein p53 and D17S22 on SMG6 gene: Smg-6 homolog, nonsense mediated mRNA decay factor- Caenorhabditis elegans). These patients performed significantly worse in the Wisconsin Card Sorting Test-Categories in comparison with patients without such variations in lissencephaly-related genes. The presence of structural variants was related to completed categories, and accounted for 10.7% of the variance (P= 0.001). Finally, logistic regression showed that poor Wisconsin Card Sorting Test-Categories performance was the only predictor of belonging to the positive LCR variations group. These new findings provide further evidence for the association between some lissencephaly-related genes and both schizophrenia and bipolar disorder, and influence on frontal executive functioning. © 2008 Wolters Kluwer Health|Lippincott Williams & Wilkins.FIS-MSC PI051293, AstraZeneca, Spanish Ministry of Health, Instituto de Salud Carlos III, Ciber en Salud Mental (CIBER-SAM) GV2005-303.Peer Reviewe