DISEÑO Y CONTROL DE ORIENTACIÓN PARA UN SISTEMA ESTABILIZADOR DE TRES GRADOS DE LIBERTAD (DESIGN AND ORIENTATION CONTROL FOR A THREE DEGREE FREEDOM STABILIZING SYSTEM)

Resumen  En este artículo se presenta el diseño y control de un robot gimbal de tres grados de libertad. Se muestra el desarrollo del robot, desde la representación geométrica de los movimientos que afectan al sistema con apoyo de los cambios que hay en el marco coordenado, hasta su modelado 3D y el proceso de construcción del ensamble físico. Se diseñaron varios experimentos para aplicar el sistema de control PID. En lo que se refiere a la ejecución en tiempo real, el gimbal presenta limitaciones en cuanto a los grados de movimiento y el peso máximo que puede mover. Los resultados obtenidos son satisfactorios para la aplicación de estabilizar una cámara de grabación de video.Palabra(s) Clave: control PID, ejes de rotación, estabilización, gimbal, simulación. Abstract  This article presents the design and control of a gimbal robot that moves freely throughout three axes. It shows the development of the robot fully from a geometric representation of the movements that affect the system with backup from the changes made over the reference frames, to the 3D modeling and the construction process of the physical assembly. Various experiments were designed to apply PID system controller. In terms of real time execution, the robot presents a limit on movement degrees and the maximum weight it can withstand, although the results were satisfying regarding the application of the stabilization of a video camera.  Keywords:  gimbal, PID control, rotation axes, simulation, stabilization

Association between convalescent plasma treatment and mortality in COVID-19: a collaborative systematic review and meta-analysis of randomized clinical trials.

Funder: laura and john arnold foundationBACKGROUND: Convalescent plasma has been widely used to treat COVID-19 and is under investigation in numerous randomized clinical trials, but results are publicly available only for a small number of trials. The objective of this study was to assess the benefits of convalescent plasma treatment compared to placebo or no treatment and all-cause mortality in patients with COVID-19, using data from all available randomized clinical trials, including unpublished and ongoing trials (Open Science Framework, https://doi.org/10.17605/OSF.IO/GEHFX ). METHODS: In this collaborative systematic review and meta-analysis, clinical trial registries (ClinicalTrials.gov, WHO International Clinical Trials Registry Platform), the Cochrane COVID-19 register, the LOVE database, and PubMed were searched until April 8, 2021. Investigators of trials registered by March 1, 2021, without published results were contacted via email. Eligible were ongoing, discontinued and completed randomized clinical trials that compared convalescent plasma with placebo or no treatment in COVID-19 patients, regardless of setting or treatment schedule. Aggregated mortality data were extracted from publications or provided by investigators of unpublished trials and combined using the Hartung-Knapp-Sidik-Jonkman random effects model. We investigated the contribution of unpublished trials to the overall evidence. RESULTS: A total of 16,477 patients were included in 33 trials (20 unpublished with 3190 patients, 13 published with 13,287 patients). 32 trials enrolled only hospitalized patients (including 3 with only intensive care unit patients). Risk of bias was low for 29/33 trials. Of 8495 patients who received convalescent plasma, 1997 died (23%), and of 7982 control patients, 1952 died (24%). The combined risk ratio for all-cause mortality was 0.97 (95% confidence interval: 0.92; 1.02) with between-study heterogeneity not beyond chance (I2 = 0%). The RECOVERY trial had 69.8% and the unpublished evidence 25.3% of the weight in the meta-analysis. CONCLUSIONS: Convalescent plasma treatment of patients with COVID-19 did not reduce all-cause mortality. These results provide strong evidence that convalescent plasma treatment for patients with COVID-19 should not be used outside of randomized trials. Evidence synthesis from collaborations among trial investigators can inform both evidence generation and evidence application in patient care

Cápsulas de polvo de arándano (Vaccinium corymbosum L.) como propuesta nutracéutica para mejorar la estabilidad gastrointestinal in vitro de compuestos fenólicos

El arándano (Vaccinium corymbosum L.) posee un alto contenido de compuestos fenólicos los cuales han sido estudiados principalmente por su actividad antioxidante, antiobesogénica, antiinflamatoria, entre otras. Objetivo. Evaluar el efecto de la digestión gastrointestinal in vitro sobre la bioaccesibilidad de compuestos fenólicos y actividad antioxidante de una formulación nutracéutica de arándano (cápsula), comparado con arándano fresco y polvo. Materiales y métodos. Se obtuvieron extractos metanólicos de muestras de arándano fresco y liofilizado y se determinó su contenido de fenoles, flavonoides y antocianinas totales, así como también actividad antioxidante. Se llevó a cabo un ensayo de simulación de digestión gastrointestinal para evaluar la bioaccesibilidad de los compuestos fenólicos presentes en las muestras. Resultados. Los resultados mostraron que la digestión gástrica de arándano en polvo y en cápsula promovió una mayor bioaccesibilidad de fenoles (42% y 40%), flavonoides (52% y 33%) y antocianinas (45% y 40%) comparado con digestos de arándano fresco. Posterior a la digestión intestinal, la bioaccesibilidad de fenoles (63%) y flavonoides (67%) fue mayor en la cápsula de arándano comparada con su contraparte arándano en polvo. Las condiciones de digestión intestinal afectaron negativamente la bioaccesibilidad de las antocianinas independientemente del tipo de muestra evaluada. Conclusión. Las condiciones de digestión gástrica promueven una mayor estabilidad de los compuestos fenólicos en arándano en polvo y en cápsula lo que pudiera ser relevante para el mantenimiento de un ambiente antioxidante a este nivel. Las condiciones de digestión intestinal afectaron de manera particular a los compuestos fenólicos de arándano fresco y polvo, pero no a la cápsula, lo que puede sugerir que el encapsulamiento protegió de las condiciones alcalinas a los fenoles presentes. Se sugieren estudios posteriores sobre absorción in vitro de los componentes remanentes en intestino y sus posibles efectos sobre biomarcadores de estrés oxidativo en modelos in viv

Diseño y Control de Orientación para un Sistema Estabilizador de Tres Grados de Libertad

This article presents the design and control of a gimbal robot that moves freely throughout three axes. It shows the development of the robot fully from a geometric representation of the movements that affect the system with backup from the changes made over the reference frames, to the 3D modeling and the construction process of the physical assembly. Various experiments were designed to apply PID system controller. In terms of real time execution, the robot presents a limit on movement degrees and the maximum weight it can withstand, although the results were satisfying regarding the application of the stabilization of a video camera

Average topological features of the seven families within the Anoctamin Superfamily.

<p>Plots for all families were generated with the AveHAS [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0192851#pone.0192851.ref106" target="_blank">106</a>] program. Each plot is composed of two curves. Top dark red lines represent average hydropathy. Bottom gray dotted lines represent average similarity. Predicted TMSs are shown as vertical gray lines. Numbered bars above the hydropathy curves indicate the positions of peaks of hydrophobicity, usually predicted to be TMSs using the HMMTOP [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0192851#pone.0192851.ref096" target="_blank">96</a>] and WHAT [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0192851#pone.0192851.ref095" target="_blank">95</a>] programs. This figure shows that there are 8 to 10 hydrophobicity peaks in all seven families, which likely correspond to 9 or 10 TMS, since, in this superfamily, some hydrophobicity peaks (such as peak 7 in <b>A</b>) are composed of 2 TMSs. The similarity curves indicate that the regions containing TMSs have the highest levels of conservation, and the corresponding multiple alignments shows that they have fewer gaps.</p

MAST output containing the top 3 motifs identified by MEME.

<p>The figure shows sequences with motif E-values < 10⁻³⁹. Motif 1 (red boxes) maps to TMSs 7 and 8, where 4 of the 6 Ca²⁺-binding residues in nhTMEM16 are located. Motif 2 (cyan boxes) maps to TMSs 4 and 5 in nhTMEM16, which form part of the subunit cavity for phospholipid translocation. Motif 3 (green boxes) maps to TMS 1, but this TMS does not interact with Ca²⁺ or the substrate. Our results show that 94% (65/69) of the sequences in the superfamily map Motif 1 to the region that contains 4 of the 6 functional residues that bind Ca²⁺, and 98.5% (68/69) of the sequences map Motif 2 to TMSs 4 and 5.</p

Average protein sizes, numbers of predicted TMSs (based on average hydropathy plots) and source phyla for each of the seven major families in the Anoctamin Superfamily.

<p>Average protein sizes, numbers of predicted TMSs (based on average hydropathy plots) and source phyla for each of the seven major families in the Anoctamin Superfamily.</p

Phylogenetic tree of protein members of the Anoctamin Superfamily.

<p>The tree was generated with MrBayes [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0192851#pone.0192851.ref098" target="_blank">98</a>]. The multiple alignment used to build this tree was generated with MAFFT [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0192851#pone.0192851.ref104" target="_blank">104</a>] and trimmed with trimAL [<a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0192851#pone.0192851.ref105" target="_blank">105</a>] to ensure that each residue position in the alignment contained less than 15% gaps. The seven families are labeled as indicated in the text. The labels of the leaves correspond to the last 2 components of their TC identifier. Complete TC identifiers result from inserting “1.A.17.” to the left of each leaf label.</p