A simplified analytical model for radiation dominated ignition of solid fuels exposed to multiple non-steady heat fluxes

Heat fluxes from fires are strongly time-dependent. Historically, the thermal ignition theory in its classical form has neglected this time dependency until recent years, where theories have been developed to include time-varying incident heat fluxes. This article proposes a simplified general model formulation for the heating of solid fuels exposed to four different heat flux behaviors, considering the penetration of radiation into the medium. The incident heat flux cases developed where: Constant, Linear, Exponential and Polynomial, which represent different situations related to structural and wildland fires. The analytical models consider a spatially averaged medium temperature and exact and approximate solutions are presented, based on the critical ignition temperature criterion, which are valid for solids of any optical thickness. The results were validated by comparison with various models presented in the literature, where the model granted in this work was capable to adjust to all of them, especially when high heat fluxes are involved. Therefore, the proposed model acquires a significant engineering utility since it provides a single model to be used as a general and versatile tool to predict the ignition delay time in a manageable way for solid fuels exposed to different fire conditions

Harvesting Electricity with Geobacter bremensis Isolated from Compost

Electrochemically active (EA) biofilms were formed on metallic dimensionally stable anode-type electrode (DSA), embedded in garden compost and polarized at +0.50 V/SCE. Analysis of 16S rRNA gene libraries revealed that biofilms were heavily enriched in Deltaproteobacteria in comparison to control biofilms formed on non-polarized electrodes, which were preferentially composed of Gammaproteobacteria and Firmicutes. Among Deltaproteobacteria, sequences affiliated with Pelobacter and Geobacter genera were identified. A bacterial consortium was cultivated, in which 25 isolates were identified as Geobacter bremensis. Pure cultures of 4 different G. bremensis isolates gave higher current densities (1400 mA/m2 on DSA, 2490 mA/m2 on graphite) than the original multi-species biofilms (in average 300 mA/m2 on DSA) and the G. bremensis DSM type strain (100–300 A/m2 on DSA; 2485 mA/m2 on graphite). FISH analysis confirmed that G. bremensis represented a minor fraction in the original EA biofilm, in which species related to Pelobacter genus were predominant. The Pelobacter type strain did not show EA capacity, which can explain the lower performance of the multi-species biofilms. These results stressed the great interest of extracting and culturing pure EA strains from wild EA biofilms to improve the current density provided by microbial anodes

The Mars Microphone onboard SuperCam

The Mars Microphone is one of the five measurement techniques of SuperCam, an improved version of the ChemCam instrument that has been functioning aboard the Curiosity rover for several years. SuperCam is located on the Rover's Mast Unit, to take advantage of the unique pointing capabilities of the rover's head. In addition to being the first instrument to record sounds on Mars, the SuperCam Microphone can address several original scientific objectives: the study of sound associated with laser impacts on Martian rocks to better understand their mechanical properties, the improvement of our knowledge of atmospheric phenomena at the surface of Mars: atmospheric turbulence, convective vortices, dust lifting processes and wind interactions with the rover itself. The microphone will also help our understanding of the sound signature of the different movements of the rover: operations of the robotic arm and the mast, driving on the rough floor of Mars, monitoring of the pumps, etc ... The SuperCam Microphone was delivered to the SuperCam team in early 2019 and integrated at the Jet Propulsion Laboratory (JPL, Pasadena, CA) with the complete SuperCam instrument. The Mars 2020 Mission launched in July 2020 and landed on Mars on February 18th 2021. The mission operations are expected to last until at least August 2023. The microphone is operating perfectly.Comment: 40 page

Desarrollo de lista corta para la evaluación del desempeño en alimentación-deglución en niños entre 1 y 5 años de edad con parálisis cerebral

Tesis (Fonoaudiólogo)La alimentación dentro de nuestra sociedad cumple un rol importante, ya sea, dentro de la dinámica familiar así como en las relaciones sociales, ya que, la comida genera momentos de diálogo y encuentro, es por esta razón, que es fundamental buscar la integración y un manejo adecuado durante el proceso de alimentación. Sin embargo, los niños con parálisis cerebral presentan numerosas dificultades frente a este proceso, por lo tanto, lo principal es no aislar al menor durante estas situaciones, sino que se debe manejar el contexto de manera óptima donde sea placentero para el niño, el cuidador y su entorno y de esta forma mejorar su calidad de vida. La investigación expuesta a continuación tiene dos propósitos, el primero es contar con un instrumento que permita valorar el desempeño de alimentación - deglución en niños con Parálisis Cerebral entre 1 y 5 años y el segundo, es lograr crear perfiles cualitativos, basándose en la Clasificación Internacional del Funcionamiento y la Discapacidad (CIF), esta permite integrar los componentes de actividad y participación, los cuales son fundamentales para los terapeutas que se desenvuelve en el área de la rehabilitación, esperando que los niños con Parálisis Cerebral obtengan mayor funcionalidad e integración en la sociedad. Es necesario tener en cuenta que en este estudio, los menores no presentan autonomía durante el acto de alimentación y esto genera un grado de dependencia de un tercero, es por esto que el fonoaudiólogo cumple un rol importante en la rehabilitación de la alimentación- deglución, siendo necesario conocer los factores en función de la CIF que influyen durante la alimentación, para así encasillar el rendimiento del menor durante la alimentación y conocer sus fortalezas, potenciandolas al máximo y compensando las debilidades. Por lo tanto, el objetivo de esta tesis es diseñar una lista corta para la evaluación del desempeño en la alimentación en el rango etario mencionado anteriormente, para caracterizar el desempeño del evaluado y crear perfiles cualitativos que guíen la futura intervención. Además, de poder comparar cuantitativamente el desempeño según las siguientes variables: tipo de parálisis cerebral, vía de alimentación y consistencias de los alimentos. Sin embargo, debido al corto tiempo asignado para esta investigación, la tesis abordará el primer propósito que consiste en la creación del instrumento. Por lo tanto, la base de este estudio es dar a conocer los procedimientos y análisis de la creación de este. Por consiguiente, se deja abierta la posibilidad de continuar con esta investigación para finalizar el segundo propósito. Los dejamos invitados a revisar esta investigación, ya que como terapeutas es de vital importancia conocer anticipadamente el desarrollo de la evolución de la alimentación en los niños con distintos tipos de PC y así poder abordar la intervención de manera más integral

Design, development, and scientific performance of the Raman Laser Spectrometer EQM on the 2020 ExoMars (ESA) Mission

The Raman Laser Spectrometer (RLS) is one of the three Pasteur Payload instruments located within the rover analytical laboratory drawer (ALD), for ESA’s Aurora exploration programme, ExoMars 2020 mission. The instrument will analyse the crushed surface and subsurface samples that are positioned below the Raman optical head by the ALD carousel. The RLS engineering and qualification model (EQM) was delivered to ESA at the end of 2017, after a wide technical and scientific test characterization campaign. The scientific campaign comprised instrument calibration and detailed evaluation of the scientific requirements and overall performance. For spectral calibration, continuous emission standard lamps (such as Hg-Ar, Ne, and Xe) were utilized, as well as Raman spectra of pure liquids typically used as standards (cyclohexane and carbon tetrachloride (CCl4)). In addition, Raman spectra of the RLS calibration target (CT), a small disc of polyethylene terephthalate (PET) were obtained at various temperatures. This target, placed inside the rover, will be used for both Instrument health checks and calibration activities throughout Mars operations. For the scientific requirements and performance evaluations, several liquid and solid samples were analysed under a wide range of ambient conditions. The obtained spectral band parameters (peak position, relative peak intensity, peak width, and peak profile) were evaluated. Also, the instrument response (in terms of SNR) was characterized at different integration times and detector operating temperatures. In this paper, we provide a description of the development, verification, functional test, and overall scientific performance of the RLS instrument developed for ExoMars. Particular attention is placed on the performance of the EQM, which is the most representative instrument, in terms of engineering and functionality, of the flight model (FM) and in addition is used for performing all the mechanical, thermal, and radiation tests necessary for space qualification (for planetary applications). The data presented and analysed here, comprise part of the overall dataset obtained during the full instrument characterization campaign conducted at INTA before and during delivery and integration of the EQM in the rover ALD at TAS-I facilities (Torino, Italy). The results obtained confirm that the full functionality and scientific performance of the RLS instrument was maintained after integration.Proyecto MINECO Retos de la Sociedad. Ref. ESP2017-87690-C3-1-

Physicochemical characterization and quantification of nanoplastics: applicability, limitations and complementarity of batch and fractionation methods

A comprehensive physicochemical characterization of heterogeneous nanoplastic (NPL) samples remains an analytical challenge requiring a combination of orthogonal measurement techniques to improve the accuracy and robustness of the results. Here, batch methods, including dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), tunable resistive pulse sensing (TRPS), transmission electron microscopy (TEM), and scanning electron microscopy (SEM), as well as separation/fractionation methods such as centrifugal liquid sedimentation (CLS) and field-flow fractionation (FFF)–multi-angle light scattering (MALS) combined with pyrolysis gas chromatography mass spectrometry (pyGC–MS) or Raman microspectroscopy (RM) were evaluated for NPL size, shape, and chemical composition measurements and for quantification. A set of representative/test particles of different chemical natures, including (i) polydisperse polyethylene (PE), (ii) (doped) polystyrene (PS) NPLs, (iii) titanium dioxide, and (iv) iron oxide nanoparticles (spherical and elongated), was used to assess the applicability and limitations of the selected methodologies. Particle sizes and number-based concentrations obtained by orthogonal batch methods (DLS, NTA, TRPS) were comparable for monodisperse spherical samples, while higher deviations were observed for polydisperse, agglomerated samples and for non-spherical particles, especially for light scattering methods. CLS and TRPS offer further insight with increased size resolution, while detailed morphological information can be derived by electron microscopy (EM)–based approaches. Combined techniques such as FFF coupled to MALS and RM can provide complementary information on physical and chemical properties by online measurements, while pyGC–MS analysis of FFF fractions can be used for the identification of polymer particles (vs. inorganic particles) and for their offline (semi)quantification. However, NPL analysis in complex samples will continue to present a serious challenge for the evaluated techniques without significant improvements in sample preparation.publishedVersio

Conociendo y comprendiendo interacciones entre pares que generan dinámicas agresivas entre estudiantes de primero a quinto de básica primaria del instituto Rafael Núñez de la sede del barrio porfía, 2012

En la vida moderna se vive a un ritmo en el cual las relaciones afectivas se deterioran cada vez más, y la comunidad escolar por supuesto no escapa de ella; por ello el propósito de esta propuesta se efectúo con el fin de comprender las dinámicas que se presentan entre los estudiantes del plantel educativo Rafael Núñez, en el cual se observó mediante algunas visitas que los niño(a)s interactúan agresivamente. Para esta propuesta, se eligió como muestra un grupo de 60 estudiantes de básica primaria con edades entre los 6 a 13 años de la comunidad estudiantil Rafael Núñez, donde se evidenció que éste establecimiento, no es ajeno al fenómeno de las interacciones agresivas en el momento de realizar algunas acciones comunicativas entre pares; algunas de ellas se encuentran frente al entorno educativo de forma verbal o física y otras no, manteniendo así un bajo perfil no por esto menos impactantes; en muchas ocasiones estas presiones se presentan de manera grupal y acaban por coaccionar al más débil de la relación, generando un conflicto e imposibilitando de este modo establecer relaciones adecuadas entre los estudiantes. Este estudio se efectúa ya que los problemas de manifestaciones agresivas en niños, han sido motivo de estudio desde diversos contextos (legal, social, educativo y médico), y en distintas partes del mundo, por sus graves consecuencias en la formación integral del niño y en su personalidad futura como adulto. Con el propósito de acompañar a la comunidad educativa mediante el desarrollo de estrategias psicosociales, para estimular relaciones solidarias, pacificas y afectuosas, surgieron alternativas de desarrollo de habilidades individuales e inter-grupales en las aulas escolares, logrando mejorar con esto prácticas de comunicación humana, las relaciones consigo mismo, con los demás, con el entorno, en donde se da un abordaje de conflictos a fin de mejorar el clima escolar y transformar la cultura institucional, para lo cual se usó el desarrollo de las temáticas: habilidades sociales, relaciones humanas, comunicación humana y abordaje de conflictos.In modern life is lived at a pace which affective relations deteriorate more and more, and the school community of course not escape from it, hence the purpose of this proposal was made to understand the dynamics present among students of campus Rafael Nunez, which was observed by several visits to the child’s interact aggressively. For this proposal, was chosen as a sample group of 60 primary school students aged 6 to 13 years of the student community Rafael Nunez, where it was shown that this facility is no stranger to the phenomenon of aggressive interactions at the time to perform some communicative actions between pairs, some of them are facing the educational environment of verbal or physical and not others, thus maintaining a low profile is no less impressive, in many cases, these pressures are presented in groups and eventually coerce the weaker the relationship, creating a conflict and thus impossible to establish appropriate relationships with students. This study was done because the problems of aggressive manifestations in children, have been studied from different contexts (legal, social, educational and medical), and in different parts of the world for its serious consequences in the integral formation of children and in its future as an adult personality. In order to accompany the educational community through the development of psychosocial strategies to encourage supportive relationships, peaceful and loving, there were alternatives to develop individual skills and inter-group in the classroom, getting better with this practice of human communication, relationships with self, others, with the environment, where there is a conflict management to improve school climate and transform the institutional culture, which was used for the development of themes: social skills, human relations , human communication and conflict management

High-Fidelity Simulation Nurse Training Reduces Unplanned Interruption of Continuous Renal Replacement Therapy Sessions in Critically Ill Patients: The SimHeR Randomized Controlled Trial

BACKGROUND: Although continuous renal replacement therapy (CRRT) is common, unplanned interruptions (UI) often limit its usefulness. In many units, nurses are responsible for CRRT management. We hypothesized that a nurse training program based on high-fidelity simulation would reduce the rate of interrupted sessions. METHODS: We performed a 2-phase (training and evaluation), randomized, single-center, open study: During the training phase, intensive care unit nurses underwent a 6-hour training program and were randomized to receive (intervention) or not (control) an additional high-fidelity simulation training (6 hours). During the evaluation phase, management of CRRT sessions was randomized to either intervention or control nurses. Sessions were defined as UI if they were interrupted and the interruption was not prescribed in writing more than 3 hours before. RESULTS: Study nurses had experience with hemodialysis, but no experience with CRRT before training. Intervention nurses had higher scores than control nurses on the knowledge tests (grade, median [Q1-Q3], 14 [10.5-15] vs 11 [10-12]/20; P = .044). During a 13-month period, 106 sessions were randomized (n = 53/group) among 50 patients (mean age 70 ± 13 years, mean simplified acute physiology II score 69 [54-96]). Twenty-one sessions were not analyzed (4 were not performed and 17 patients died during sessions). Among the 42 intervention and 43 control sessions analyzed, 25 (59%) and 38 (88%) were labeled as UI (relative risk [95% CI], 0.67 [0.51-0.88]; P = .002). Intervention nurses required help significantly less frequently (0 [0-1] vs 3 [1-4] times/session; P < .0001). The 2 factors associated with UI in multilevel mixed-effects logistic regression were Sequential Organ Failure Assessment score (odds ratio [95% CI], 0.81 [0.65-99]; P = .047) and the intervention group (odds ratio, 0.19 [0.05-0.73]; P = .015). CONCLUSIONS: High-fidelity simulation nurse training reduced the rate of UI of CRRT sessions and the need for nurses to request assistance. This intervention may be particularly useful in the context of frequent nursing staff turnover

Impact of 18F-fluoro-deoxy-glucose positron emission tomography (FDG-PET) in recurrent colorectal cancer

Purpose: The aim of the study was to evaluate the diagnostic performance, the prognosis factors and the therapeutic impact of 18F-FDG positron emission tomography (FDG-PET) in the detection of recurrent colorectal cancers. Methods: Sixty PET/CT with 18F-FDG and CT were performed in 52 patients, at the Paul Papin cancer center between 2003 and 2005, following suspicion of colorectal cancer relapse. The FDG-PET impact on the clinical management was studied by examination of multidisciplinary concertations results. Survival analysis were realized with a mean follow up of 2.2 years. Results: Recurrence was confirmed for 50 explorations by histologic (n = 32), radiologic (n = 14) or clinical (n = 4) findings. Twenty patients died during the time of the study. On a patient based analysis, FDG-PET sensitivity, specificity and overall accuracy were 90, 90, 90% respectively compared with 74, 50 and 70% for CT. FDG-PET changed the clinical management in 18 cases (30%). A positive FDG-PET signal, more than one hepatic lesion, more than two lymph node lesions detected on FDG-PET and more than two hepatic lesions on CT were characterized as bad prognostic factors for survival. Multivariate analysis showed that the only independent bad prognostic factor was the FDG-PET detection of more than two liver lesions. Conclusion: These results confirmed the important impact of FDG-PET in the clinical management of patients with a suspected recurrence of colorectal cancer

Membrane Surface Nanostructures and Adhesion Property of T Lymphocytes Exploited by AFM

The activation of T lymphocytes plays a very important role in T-cell-mediated immune response. Though there are many related literatures, the changes of membrane surface nanostructures and adhesion property of T lymphocytes at different activation stages have not been reported yet. However, these investigations will help us further understand the biophysical and immunologic function of T lymphocytes in the context of activation. In the present study, the membrane architectures of peripheral blood T lymphocytes were obtained by AFM, and adhesion force of the cell membrane were measured by acquiring force–distance curves. The results indicated that the cell volume increased with the increases of activation time, whereas membrane surface adhesion force decreased, even though the local stiffness for resting and activated cells is similar. The results provided complementary and important data to further understand the variation of biophysical properties of T lymphocytes in the context of in vitro activation