Respuesta dinámica de los muros de la envolvente edilicia a variaciones diurnas de la temperatura exterior

Se presentan resultados de la simulación numérica que resuelve la ecuación del calor dependiente del tiempo, que permiten evaluar el comportamiento térmico de muros multi-capas de construcciones típicas del centro bonaerense ante las variaciones diurnas de la temperatura exterior. Se cuantifica el intercambio energético por conducción y se encuentran los respectivos factores de decremento y tiempos de retraso, los que son comparados con los valores obtenidos aplicando el método de la admitancia, encontrándose un buen acuerdo. La simulación numérica permite describir detalladamente la evolución del flujo de energía en el interior de las paredes, contribuyendo a mejorar la comprensión de situaciones físicas complejas asociadas con envolventes multi-capas (y por ende, con la introducción de interfaces térmicas) y a determinar la influencia de las condiciones de contorno elegidas sobre los resultados. Así es posible mostrar los efectos generados en cada capa de material que suelen quedar encubiertos cuando se aplican métodos analíticos generales, destacándose la importancia de la selección de los materiales y su disposición en el interior del muro.In this paper results of numerical simulations that solve the non-steady heat equation are presented, thus providing the thermal assessment of typical walls composed of multiple layers of homogeneous materials and subjected to a diurnal variation of the outdoor temperature. The heat flux by conduction is quantified while the decrement factor and the time lag are estimated and compared to the admittance method results, finding a good agreement. Numerical results provide detailed information on the heat flux evolution within the walls, which helps to improve the understanding of complex physical situations associated with multilayer envelopes (and hence, with the insertion of thermal interfaces), and to determine the boundary conditions effects on the results. The effects on layers, which use to remain undercover when general analytical methods are applied, are now showed thus highlighting the importance of the proper choice of material and its localization inside the wall

Design of Lactococcus lactis Strains Producing Garvicin A and/or Garvicin Q, Either Alone or Together with Nisin A or Nisin Z and High Antimicrobial Activity against Lactococcus garvieae

Lactococcus garvieae is a main ichthyopathogen in rainbow trout (Oncorhynchus mykiss, Walbaum) farming, although bacteriocinogenic L. garvieae with antimicrobial activity against virulent strains of this species have also been identified. Some of the bacteriocins characterized, such as garvicin A (GarA) and garvicin Q (GarQ), may show potential for the control of the virulent L. garvieae in food, feed and other biotechnological applications. In this study, we report on the design of Lactococcus lactis strains that produce the bacteriocins GarA and/or GarQ, either alone or together with nisin A (NisA) or nisin Z (NisZ). Synthetic genes encoding the signal peptide of the lactococcal protein Usp45 (SPusp45), fused to mature GarA (lgnA) and/or mature GarQ (garQ) and their associated immunity genes (lgnI and garI, respectively), were cloned into the protein expression vectors pMG36c, which contains the P32 constitutive promoter, and pNZ8048c, which contains the inducible PnisA promoter. The transformation of recombinant vectors into lactococcal cells allowed for the production of GarA and/or GarQ by L. lactis subsp. cremoris NZ9000 and their co-production with NisA by Lactococcus lactis subsp. lactis DPC5598 and L. lactis subsp. lactis BB24. The strains L. lactis subsp. cremoris WA2-67 (pJFQI), a producer of GarQ and NisZ, and L. lactis subsp. cremoris WA2-67 (pJFQIAI), a producer of GarA, GarQ and NisZ, demonstrated the highest antimicrobial activity (5.1- to 10.7-fold and 17.3- to 68.2-fold, respectively) against virulent L. garvieae strains.Sección Dptal. de Nutrición y Ciencia de los Alimentos (Veterinaria)Fac. de VeterinariaTRUEMinisterio de Ciencia, Innovación y Universidades (MCIU)Universidad Complutense de Madrid and Banco de SantanderUniversidad Complutense de Madridpu

Diseño y prueba de un robot móvil con tres niveles de complejidad para la experimentación en robótica

Un robot móvil (llamado UV-BOT), fue diseñado en la Universidad del Valle para la experimentación en robótica y puede ser usado por personas con o sin conocimiento en robótica. UV-BOT es un robot diferencial y para uso en interiores; cuenta con sensores de proximidad, detección de luz, localización y comunicaciones, y su velocidad es controlada mediante dos controladores PI, uno en cada rueda. El firmware del robot fue diseñado usando un micro-núcleo de tiempo real conocido como FreeRTOS, que soporta tres niveles de complejidad, los cuales poseen un conjunto de funcionalidades desde el punto de vista de percepción, movilidad, comuno en la Universidad del Valle para la experimentación en robótica y puede ser usado por personas con o sin conocimiento en robótica. UV-BOT es un robot diferencial y para uso en interiores; cuenta con sensores de proximidad, detección de luz, localización y comunicaciones, y su velocidad es controlada mediante dos controladores PI, uno en cada rueda. El firmware del robot fue diseñado usando un micro-núcleo de tiempo real conocido como FreeRTOS, que soporta tres niveles de complejidad, los cuales poseen un conjunto de funcionalidades desde el punto de vista de percepción, movilidad, comunicación, programación y disponibilidad de demos. Estas funcionalidades son empleadas por la interfaz de usuario para programar el robot gráficamente (nivel básico), usando XML (nivel intermedio) o C (nivel avanzado). En su nivel avanzado, el robot soporta la programación orientada a comportamientos. Estos comportamientos fueron utilizados para realizar las pruebas de desempeño del robot móvil. Como resultado de estas pruebas, se encontró que el sistema de localización de UVBOT muestra una incertidumbre promedio de 17 cm. Los comportamientos de retorno (por posición y luz) y evasión de obstáculos muestran errores promedio de 15 y 12 cm, respectivamente. De este modo, con UV-BOT se pueden implementar exitosamente tareas básicas en robótica cooperativa

Primary care randomized clinical trial: manual therapy effectiveness in comparison with TENS in patients with neck pain

This study investigated effectiveness of manual therapy (MT) with transcutaneous electrical nerve stimulation (TENS) to reduce pain intensity in patients with mechanical neck disorder (MND). A randomized multi-centered controlled clinical trial was performed in 12 Primary Care Physiotherapy Units in Madrid Region. Ninety patients were included with diagnoses of subacute or chronic MND without neurological damage, 47 patients received MT and 43 TENS. The primary outcome was pain intensity measured in millimeters using the Visual Analogue Scale (VAS). Also disability, quality of life, adverse effects and sociodemographic and prognosis variables were measured. Three evaluations were performed (before, when the procedure ?nished and six months after). Seventy-one patients (79%) completed the follow-up measurement at six months. In more than half of the treated patients the procedure had a clinically relevant ?short term? result after having ended the intervention, when either MT or TENS was used. The success rate decreased to one-third of the patients 6 months after the intervention. No differences can be found in the reduction of pain, in the decrease of disability nor in the quality of life between both therapies. Both analyzed physiotherapy techniques produce a short-term pain reduction that is clinically relevant.Ministerio de SanidadInstituto de Salud Carlos II

Chromosome-Level Genome Assembly of the Blue Mussel Mytilus chilensis Reveals Molecular Signatures Facing the Marine Environment

The blue mussel Mytilus chilensis is an endemic and key socioeconomic species inhabiting the southern coast of Chile. This bivalve species supports a booming aquaculture industry, which entirely relies on artificially collected seeds from natural beds that are translocated to diverse physical–chemical ocean farming conditions. Furthermore, mussel production is threatened by a broad range of microorganisms, pollution, and environmental stressors that eventually impact its survival and growth. Herein, understanding the genomic basis of the local adaption is pivotal to developing sustainable shellfish aquaculture. We present a high-quality reference genome of M. chilensis, which is the first chromosome-level genome for a Mytilidae member in South America. The assembled genome size was 1.93 Gb, with a contig N50 of 134 Mb. Through Hi-C proximity ligation, 11,868 contigs were clustered, ordered, and assembled into 14 chromosomes in congruence with the karyological evidence. The M. chilensis genome comprises 34,530 genes and 4795 non-coding RNAs. A total of 57% of the genome contains repetitive sequences with predominancy of LTR-retrotransposons and unknown elements. Comparative genome analysis of M. chilensis and M. coruscus was conducted, revealing genic rearrangements distributed into the whole genome. Notably, transposable Steamer-like elements associated with horizontal transmissible cancer were explored in reference genomes, suggesting putative relationships at the chromosome level in Bivalvia. Genome expression analysis was also conducted, showing putative genomic differences between two ecologically different mussel populations. The evidence suggests that local genome adaptation and physiological plasticity can be analyzed to develop sustainable mussel production. The genome of M. chilensis provides pivotal molecular knowledge for the Mytilus complex

Self-assembled three-dimensional hydrogels based on graphene derivatives and cerium oxide nanoparticles: scaffolds for co-culture of oligodendrocytes and neurons derived from neural stem cells

Stem cell-based therapies have shown promising results for the regeneration of the nervous system. However, the survival and integration of the stem cells in the neural circuitry is suboptimal and might compromise the therapeutic outcomes of this approach. The development of functional scaffolds capable of actively interacting with stem cells may overcome the current limitations of stem cell-based therapies. In this study, three-dimensional hydrogels based on graphene derivatives and cerium oxide (CeO2) nanoparticles are presented as prospective supports allowing neural stem cell adhesion, migration and differentiation. The morphological, mechanical and electrical properties of the resulting hydrogels can be finely tuned by controlling several parameters of the self-assembly of graphene oxide sheets, namely the amount of incorporated reducing agent (ascorbic acid) and CeO2 nanoparticles. The intrinsic properties of the hydrogels, as well as the presence of CeO2 nanoparticles, clearly influence the cell fate. Thus, stiffer adhesion substrates promote differentiation to glial cell lineages, while softer substrates enhance mature neuronal differentiation. Remarkably, CeO2 nanoparticle-containing hydrogels support the differentiation of neural stem cells to neuronal, astroglial and oligodendroglial lineage cells, promoting the in vitro generation of nerve tissue grafts that might be employed in neuroregenerative cell therapies

Experiencias de estudiantes voluntarios en PROCOPIN (Programa de Control de las Parasitosis Intestinales y Nutrición)

En Argentina, la frecuencia de parasitosis intestinales en asentamientos precarios varía entre 60–70%. Los parásitos producen anemia, desnutrición proteica-energética y diarreas graves, entre otras. Estas patologías suelen ser de evolución crónica, y van deteriorando lentamente al individuo parasitado, de tal manera que no percibe la afectación de su organismo hasta que se llega a un estado irreversible. Como estudiantes voluntarios integrantes de PROCOPIN, este proyecto nos forma y nos entrena para lograr un reconocimiento “en terreno” de las enfermedades parasitarias que conocemos por los libros. El programa es sistemático y secuenciado, orientado a un diagnóstico situacional y a una posterior intervención que revierta la realidad desfavorable de diversas comunidades.Facultad de Ciencias Médica

Clinical and Epidemiologic Research Measuring Trachomatous Inflammation-Intense (TI) When Prevalence Is Low Provides Data on Infection With Chlamydia trachomatis

PURPOSE. Clinical trachoma is the current measure of effectiveness of antibiotic and environmental improvements in trachoma endemic communities. Impact assessments measure only trachomatous inflammation-follicular (TF). Trachomatous inflammation-intense (TI) is not used for decisions on stopping mass drug administration (MDA) or achieving intervention goals. We tested the supposition that TI was not associated with Chlamydia trachomatis when disease prevalence is low. METHODS. In 35 communities undergoing MDA as part of a larger project, 110 children ages 1 to 9 years were randomly selected in each community for surveys at baseline, 6, and 12 months. Both eyelids were graded for TF and TI, and a swab for detection of C. trachomatis infection was taken. RESULTS. Overall TF prevalence was 5% at baseline. Cases of TI alone constituted 15% of trachoma; 37% of TI cases had infection. At 6 and 12 months, the proportion of trachoma cases that had TI only was 13% and 20%; infection rates were similar to the rates in cases with TF alone. CONCLUSIONS. Despite low prevalence of trachoma, infection rates for TF alone and TI alone were similar at each time point. The exclusion of cases of TI alone when reporting trachoma prevalence discards additional information on infection. Trachomatous inflammation-intense could be considered as part of impact surveys

Antimicrobial activity, antibiotic susceptibility and virulence factors of Lactic Acid Bacteria of aquatic origin intended for use as probiotics in aquaculture

BACKGROUND: The microorganisms intended for use as probiotics in aquaculture should exert antimicrobial activity and be regarded as safe not only for the aquatic hosts but also for their surrounding environments and humans. The objective of this work was to investigate the antimicrobial/bacteriocin activity against fish pathogens, the antibiotic susceptibility, and the prevalence of virulence factors and detrimental enzymatic activities in 99 Lactic Acid Bacteria (LAB) (59 enterococci and 40 non-enterococci) isolated from aquatic animals regarded as human food. RESULTS: These LAB displayed a broad antimicrobial/bacteriocin activity against the main Gram-positive and Gram-negative fish pathogens. However, particular safety concerns based on antibiotic resistance and virulence factors were identified in the genus Enterococcus (86%) (Enterococcus faecalis, 100%; E. faecium, 79%). Antibiotic resistance was also found in the genera Weissella (60%), Pediococcus (44%), Lactobacillus (33%), but not in leuconostocs and lactococci. Antibiotic resistance genes were found in 7.5% of the non-enterococci, including the genera Pediococcus (12.5%) and Weissella (6.7%). One strain of both Pediococcus pentosaceus and Weissella cibaria carried the erythromycin resistance gene mef(A/E), and another two P. pentosaceus strains harboured lnu(A) conferring resistance to lincosamides. Gelatinase activity was found in E. faecalis and E. faecium (71 and 11%, respectively), while a low number of E. faecalis (5%) and none E. faecium exerted hemolytic activity. None enterococci and non-enterococci showed bile deconjugation and mucin degradation abilities, or other detrimental enzymatic activities. CONCLUSIONS: To our knowledge, this is the first description of mef(A/E) in the genera Pediococcus and Weissella, and lnu(A) in the genus Pediococcus. The in vitro subtractive screening presented in this work constitutes a valuable strategy for the large-scale preliminary selection of putatively safe LAB intended for use as probiotics in aquaculture