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This article introduces an innovative approach to significantly broaden the bandwidth of Cylindrical Dielectric Resonators. A four-element Camembert-Shaped Cylindrical Dielectric Resonator Antenna (CDRA) is presented, using an air gap separating the resonators to enhance the antenna bandwidth. The radiators, i.e., the DRA blocks, are made of high relative-permittivity ceramic material (εr = 25 & 30) and are excited by microstrip-line feed. The proposed methodology involves the strategic design of these resonators, incorporating dielectric materials to finely optimize the frequency response. Experimental validation demonstrates a remarkable improvement in bandwidth when compared to conventional methodologies. This novel technique holds immense promise for applications requiring wideband antennas. The demonstrated effectiveness of this approach not only addresses contemporary challenges but also opens up new avenues in antenna design, catering to the escalating demands of modern communication systems. In addition to the compact dimensions of the elementary radiating element, the separation distance between them, set at λ/4, enhances the array antenna overall size, and its gain is nearly 10 dBi. The proposed antenna covers cellular network applications such as UMTS mobile phone band around 2.1 GHz, as well as wireless DECT phone bands around 1.9 GHz, facilitating data transmission over short distances and beyond, with an impedance bandwidth of 20%.

Los procesos de biorremediación para la degradación de colorantes provenientes de la industria textil han sido de gran interés, debido a su capacidad para descomponer los contaminantes sin generar productos tóxicos. El azul directo 71 contiene tres grupos azoicos N=N y una estructura aromática convirtiéndolo en un compuesto difícil de degradar. Se evalúo el potencial de degradación del colorante Azul Directo 71 por bacterias del género Bacillus. Se utilizaron bacterias aisladas de sedimentos de cuencas hidrológicas, las cuales se les realizó tinción Gram y observación por microscopía electrónica de barrido. La cinética de crecimiento y biodegradación se realizó en caldo nutritivo adicionado con 100 mgL-1 de Azul Directo 71 incubándose a 37°C y 200 rpm por 5 días, se determinó el crecimiento por espectrofotometría a 600 nm y la biodegradación a 575 nm. El análisis filogenético de las cepas bacterianas se realizó amplificando la región del gen rRNA 16S. Se identificaron dos bacterias bacilares Gram positivo. El análisis filogenético identificó a la cepa ANCd110506 como Bacillus anthracis y a la cepa ANHg310511 como Bacillus thuringensis, con un índice de similitud del 97.6 % y 100 %, respectivamente. Bacillus anthracis presentó una biodegradación del 75.5 %, mientras que la cepa Bacillus thuringensis obtuvo una biodegradación del 67.9 % en 120 horas.

BackgroundCardiorespiratory decompensation (CRD) visits have a profound effect on adult emergency departments (EDs). Respiratory pathogens like respiratory syncytial virus (RSV) and influenza virus are common reasons for increased activity in pediatric EDs and are associated with CRD in the adult population. Given the seasonal aspects of such challenging pathology, it would be advantageous to predict their variations. ObjectiveThe goal of this study was to evaluate the increased burden of CRD in adult EDs during flu and bronchiolitis outbreaks in the pediatric population. MethodsAn ecological study was conducted, based on admissions to the adult ED of the Centre Hospitalier Universitaire (CHU) of Grenoble and Saint Etienne from June 29, 2015 to March 22, 2020. The outbreak periods for bronchiolitis and flu in the pediatric population were defined with a decision-making support tool, PREDAFLU, used in the pediatric ED. A Kruskal-Wallis variance analysis and a Spearman monotone dependency were performed in order to study the relationship between the number of adult ED admissions for the International Classification of Diseases (ICD)-10 codes related to cardiorespiratory diagnoses and the presence of an epidemic outbreak as defined with PREDAFLU. ResultsThe increase in visits to the adult ED for CRD and the bronchiolitis and flu outbreaks had a similar distribution pattern (CHU Saint Etienne: χ23=102.7, P

El carbono negro (CN) es un contaminante atmosférico producido de forma natural y como resultado de la combustión incompleta de combustibles fósiles, biocombustibles y biomasa. La región Paso del Norte (México-Estados Unidos) no cuenta con monitoreo continuo de CN, aun cuando México tiene la meta internacional de reducir sus emisiones en 51% para el 2030. El objetivo este estudio fue evaluar el patrón de comportamiento del CN y su correlación con óxido de nitrógeno (NOx) y carbono (CO) por su asociación a emisiones vehiculares a diésel. El monitoreo fue de octubre de 2018 a marzo de 2019 por ser los meses del año más fríos y de mayor estabilidad atmosférica en la región. Las concentraciones de CN, todos los contaminantes criterio y la meteorología se determinaron mediante etalómetro, analizadores Teledyne y estación meteorológica Campbell Scientific en la estación de referencia científica IIT-01 en Ciudad Juárez, Chihuahua, México. La correlación de Spearman arrojó una CO y NOx de R=0.735 y entre CO y CN de R=0.704. Los resultados apoyan la relación significativa entre CN y NOx de R=0.794. Los resultados apoyan la posibilidad de que la fuente del CN está asociada al tráfico vehicular y a su patrón típico de comportamiento. Además de que la correlación significativa entre el CO y CN permitirá realizar estimaciones sobre el comportamiento del CN en base a las concentraciones de CO registradas por otras estaciones. DOI: https://doi.org/10.54167/tecnociencia.v14i2.399

Survival biomass production and crop yield are heavily constrained by a wide range of environmental stresses. Several phytohormones among which abscisic acid (ABA), ethylene and salicylic acid (SA) are known to mediate plant responses to these stresses. By contrast, the role of the plant hormone auxin in stress responses remains so far poorly studied. Auxin controls many aspects of plant growth and development, and Auxin Response Factors play a key role in the transcriptional activation or repression of auxin-responsive genes through direct binding to their promoters. As a mean to gain more insight on auxin involvement in a set of biotic and abiotic stress responses in tomato, the present study uncovers the expression pattern of SlARF genes in tomato plants subjected to biotic and abiotic stresses. In silico mining of the RNAseq data available through the public TomExpress web platform, identified several SlARFs as responsive to various pathogen infections induced by bacteria and viruses. Accordingly, sequence analysis revealed that 5' regulatory regions of these SlARFs are enriched in biotic and abiotic stress-responsive cis-elements. Moreover, quantitative qPCR expression analysis revealed that many SlARFs were differentially expressed in tomato leaves and roots under salt, drought and flooding stress conditions. Further pointing to the putative role of SlARFs in stress responses, quantitative qPCR expression studies identified some miRNA precursors as potentially involved in the regulation of their SlARF target genes in roots exposed to salt and drought stresses. These data suggest an active regulation of SlARFs at the post-transcriptional level under stress conditions. Based on the substantial change in the transcript accumulation of several SlARF genes, the data presented in this work strongly support the involvement of auxin in stress responses thus enabling to identify a set of candidate SlARFs as potential mediators of biotic and abiotic stress responses.

Sl-ERF.B.3 (Solanum lycopersicum ethylene response factor B.3) gene encodes for a tomato transcription factor of the ERF (ethylene responsive factor) family. Our results of real-time RT-PCR showed that Sl-ERF.B.3 is an abiotic stress responsive gene, which is induced by cold, heat, and flooding, but downregulated by salinity and drought. To get more insight into the role of Sl-ERF.B.3 in plant response to separate salinity and cold, a comparative study between wild type and two Sl-ERF.B.3 antisense transgenic tomato lines was achieved. Compared with wild type, Sl-ERF.B.3 antisense transgenic plants exhibited a salt stress dependent growth inhibition. This inhibition was significantly enhanced in shoots but reduced in roots, leading to an increased root to shoot ratio. Furthermore, the cold stress essay clearly revealed that introducing antisense Sl-ERF.B.3 in transgenic tomato plants reduces their cell injury and enhances their tolerance against 14 d of cold stress. All these results suggest that Sl-ERF.B.3 gene is involved in plant response to abiotic stresses and may play a role in the layout of stress symptoms under cold stress and in growth regulation under salinity.

Pseudomonas aeruginosa cytotoxicity is linked to a type III secretion system (T3SS) that delivers effectors into the host cell. We show here that a negative cross-control exists between T3SS and flagellar assembly. We observed that, in a strain lacking flagella, T3SS gene expression, effector secretion, and cytotoxicity were increased. Conversely, we revealed that flagellar-gene expression and motility were decreased in a strain overproducing ExsA, the T3SS master regulator. Interestingly, a nonmotile strain lacking the flagellar filament ([DELTA]fliC) presented a hyperefficient T3SS and a nonmotile strain assembling flagella ([DELTA]motAB) did not. More intriguingly, a strain lacking motCD genes is a flagellated strain with a slight defect in swimming. However, in this strain, T3SS gene expression was up-regulated. These results suggest that flagellar assembly and/or mobility antagonizes the T3SS and that a negative cross talk exists between these two systems. An illustration of this is the visualization by electron microscopy of T3SS needles in a nonmotile P. aeruginosa strain, needles which otherwise are not detected. The molecular basis of the cross talk is complex and remains to be elucidated, but proteins like MotCD might have a crucial role in signaling between the two processes. In addition, we found that the GacA response regulator negatively affects the T3SS. In a gacA mutant, the T3SS effector ExoS is hypersecreted. Strikingly, GacA was previously reported as a positive regulator for motility. Globally, our data document the idea that some virulence factors are coordinately but inversely regulated, depending on the bacterial colonization phase and infection types.

Results show that the peptidoglycan-associated lipoprotein (Pal) is anchored to the Escherichia coli outer membrane and interacts with the other major lipoprotein Lpp. Data indicate that overproduction of Pal restores outer membrane integrity.