Inspección de subestaciones eléctricas: YOLOv5 en la identificación de puntos calientes mediante imágenes térmicas

Substations are key facilities within an electrical system, untimely failures tend to cause low quality and negative effects on the electrical supply. An early indicator of potential electrical equipment failure is the appearance of hot spots; therefore, its detection and subsequent programmed correction avoids incurring in major failures and unnecessary operation stops. In this research, 64 experiments of the YOLOv5 algorithm were carried out, with the purpose of proposing an automated computer vision mechanism for the detection of hot spots in thermal images of electrical substations. The best results show a mAP value of 81.99%, which were obtained with the YOLOv5m algorithm and the transfer learning application. These results leave a basis to deepen and improve the performance of the algorithm by varying other hyperparameters to those considered in this study.Las subestaciones son instalaciones clave dentro de un sistema eléctrico; las fallas intempestivas tienden a causar baja calidad y efectos negativos del suministro eléctrico. Un indicador temprano de posibles fallas en los equipos eléctricos es la aparición de puntos calientes; por lo que su detección y posterior corrección programada evita incurrir en fallas mayores y paradas de operación innecesarias. En esta investigación se realizaron 64 experimentos del algoritmo YOLOv5, con la finalidad de proponer un mecanismo automatizado de visión por computadora para la detección de puntos calientes en imágenes térmicas de subestaciones eléctricas. Los mejores resultados muestran un valor mAP de 81,99 %, los cuales se obtuvieron con el algoritmo YOLOv5m y la aplicación de transfer learning. Estos resultados dejan una base para profundizar y mejorar el desempeño del algoritmo, variando otros hiperparámetros a los considerados en el presente estudio

SHARDS: Constraints on the dust attenuation law of star-forming galaxies at z~2

We make use of SHARDS, an ultra-deep (<26.5AB) galaxy survey that provides optical photo-spectra at resolution R~50, via medium band filters (FWHM~150A). This dataset is combined with ancillary optical and NIR fluxes to constrain the dust attenuation law in the rest-frame NUV region of star-forming galaxies within the redshift window 1.5<z<3. We focus on the NUV bump strength (B) and the total-to-selective extinction ratio (Rv), targeting a sample of 1,753 galaxies. By comparing the data with a set of population synthesis models coupled to a parametric dust attenuation law, we constrain Rv and B, as well as the colour excess, E(B-V). We find a correlation between Rv and B, that can be interpreted either as a result of the grain size distribution, or a variation of the dust geometry among galaxies. According to the former, small dust grains are associated with a stronger NUV bump. The latter would lead to a range of clumpiness in the distribution of dust within the interstellar medium of star-forming galaxies. The observed wide range of NUV bump strengths can lead to a systematic in the interpretation of the UV slope ($\beta$) typically used to characterize the dust content. In this study we quantify these variations, concluding that the effects are $\Delta\beta$~0.4.Comment: 13 pages, 11+2 figures, 3 tables. MNRAS, in pres

Estudio a largo plazo (más de 10 años de evolución), de las complicaciones de las artroplastias trapecio-metacarpianas de tipo ARPE

Producción CientíficaResumen: Objetivo: La artrosis trapecio-metacarpiana es una patología incapacitante, que produce dolor, disminución de la fuerza, pérdida de destreza en la pinza y limitación de la movilidad del pulgar. Cuando fracasa el tratamiento médico se pueden realizar diferentes técnicas quirúrgicas. Las prótesis totales de la articulación representan una de ellas. Desde mayo de 1999 hasta abril de 2004 se realizaron, de forma consecutiva, un total de 116 prótesis totales de la articulación trapecio-metacarpiana en 103 pacientes que padecían artrosis, utilizando la prótesis no cementada y no constreñida tipo ARPE® (Biomet Spain Orthopaedics SL, Valencia). Se presentan en este estudio los resultados de la revisión clínica, funcional y radiológica de los pacientes revisados durante 10 años de evolución. Material y Método: Los análisis de supervivencia fueron realizados mediante el método de Kaplan-Meier. De los 103 pacientes, 6 fueron excluidos y 97 pacientes, con 109 prótesis acabaron el estudio. Resultados: En la revisión de los 10 años de evolución, 102 (93,6%) eran prótesis funcionales y 7 (6,4%) prótesis eran consideradas prótesis fallidas (3 retiradas por aflojamiento, 3 luxaciones y 1 subluxación y dolor). La probabilidad de supervivencia de Kaplan–Meier fue de 94.1% [CI95% (90.4%,98.8%)]. Radiográficamente, 88 (86,3%) de las prótesis consideradas funcionales no mostraron evidencia de alteraciones del implante y 14 (13,7%) mostraron cambios radiográficos que eran compatibles con la funcionalidad del implante. Se presenta en detalle el estudio de las complicaciones que han existido, con las posibles soluciones en las cirugías de revisión. Conclusión: La prótesis total de ARPE® ofrece una alternativa de tratamiento segura y fiable en pacientes con artrosis trapecio-metacarpiana grado III y algunos de grado IV con buen capital óseo, sobre todo, en el trapecio. La mayoría de las complicaciones aparecen por defectos de indicación o por defectos de la técnica quirúrgica y se pueden resolver con recambio protésico o con trapecectomía dependiendo de las circunstancias del implante y del paciente

Inspección de subestaciones eléctricas: YOLOv5 en la identificación de puntos calientes mediante imágenes térmicas

Las subestaciones son instalaciones clave dentro de un sistema eléctrico; las fallas intempestivas tienden a causar baja calidad y efectos negativos del suministro eléctrico. Un indicador temprano de posibles fallas en los equipos eléctricos es la aparición de puntos calientes; por lo que su detección y posterior corrección programada evita incurrir en fallas mayores y paradas de operación innecesarias. En esta investigación se realizaron 64 experimentos del algoritmo YOLOv5, con la finalidad de proponer un mecanismo automatizado de visión por computadora para la detección de puntos calientes en imágenes térmicas de subestaciones eléctricas. Los mejores resultados muestran un valor mAP de 81,99 %, los cuales se obtuvieron con el algoritmo YOLOv5m y la aplicación de transfer learning. Estos resultados dejan una base para profundizar y mejorar el desempeño del algoritmo, variando otros hiperparámetros a los considerados en el presente estudio

Molecules as tracers of galaxy evolution: an EMIR survey. I. Presentation of the data and first results

We investigate the molecular gas properties of a sample of 23 galaxies in order to find and test chemical signatures of galaxy evolution and to compare them to IR evolutionary tracers. Observation at 3 mm wavelengths were obtained with the EMIR broadband receiver, mounted on the IRAM 30 m telescope on Pico Veleta, Spain. We compare the emission of the main molecular species with existing models of chemical evolution by means of line intensity ratios diagrams and principal component analysis. We detect molecular emission in 19 galaxies in two 8 GHz-wide bands centred at 88 and 112 GHz. The main detected transitions are the J=1-0 lines of CO, 13CO, HCN, HNC, HCO+, CN, and C2H. We also detect HC3N J=10-9 in the galaxies IRAS 17208, IC 860, NGC 4418, NGC 7771, and NGC 1068. The only HC3N detections are in objects with HCO+/HCN<1 and warm IRAS colours. Galaxies with the highest HC3N/HCN ratios have warm IRAS colours (60/100 {\mu}m>0.8). The brightest HC3N emission is found in IC 860, where we also detect the molecule in its vibrationally excited state.We find low HNC/HCN line ratios (<0.5), that cannot be explained by existing PDR or XDR chemical models. Bright HC3N emission in HCO+-faint objects may imply that these are not dominated by X-ray chemistry. Thus the HCN/HCO+ line ratio is not, by itself, a reliable tracer of XDRs. Bright HC3N and faint HCO+ could be signatures of embedded starformation, instead of AGN activity

Recent trends in molecular diagnostics of yeast infections : from PCR to NGS

The incidence of opportunistic yeast infections in humans has been increasing over recent years. These infections are difficult to treat and diagnose, in part due to the large number and broad diversity of species that can underlie the infection. In addition, resistance to one or several antifungal drugs in infecting strains is increasingly being reported, severely limiting therapeutic options and showcasing the need for rapid detection of the infecting agent and its drug susceptibility profile. Current methods for species and resistance identification lack satisfactory sensitivity and specificity, and often require prior culturing of the infecting agent, which delays diagnosis. Recently developed high-throughput technologies such as next generation sequencing or proteomics are opening completely new avenues for more sensitive, accurate and fast diagnosis of yeast pathogens. These approaches are the focus of intensive research, but translation into the clinics requires overcoming important challenges. In this review, we provide an overview of existing and recently emerged approaches that can be used in the identification of yeast pathogens and their drug resistance profiles. Throughout the text we highlight the advantages and disadvantages of each methodology and discuss the most promising developments in their path from bench to bedside

Detecting Mutations in the Mycobacterium tuberculosis Pyrazinamidase Gene pncA to Improve Infection Control and Decrease Drug Resistance Rates in Human Immunodeficiency Virus Coinfection.

Hospital infection control measures are crucial to tuberculosis (TB) control strategies within settings caring for human immunodeficiency virus (HIV)-positive patients, as these patients are at heightened risk of developing TB. Pyrazinamide (PZA) is a potent drug that effectively sterilizes persistent Mycobacterium tuberculosis bacilli. However, PZA resistance associated with mutations in the nicotinamidase/pyrazinamidase coding gene, pncA, is increasing. A total of 794 patient isolates obtained from four sites in Lima, Peru, underwent spoligotyping and drug resistance testing. In one of these sites, the HIV unit of Hospital Dos de Mayo (HDM), an isolation ward for HIV/TB coinfected patients opened during the study as an infection control intervention: circulating genotypes and drug resistance pre- and postintervention were compared. All other sites cared for HIV-negative outpatients: genotypes and drug resistance rates from these sites were compared with those from HDM. HDM patients showed high concordance between multidrug resistance, PZA resistance according to the Wayne method, the two most common genotypes (spoligotype international type [SIT] 42 of the Latino American-Mediterranean (LAM)-9 clade and SIT 53 of the T1 clade), and the two most common pncA mutations (G145A and A403C). These associations were absent among community isolates. The infection control intervention was associated with 58-92% reductions in TB caused by SIT 42 or SIT 53 genotypes (odds ratio [OR] = 0.420, P = 0.003); multidrug-resistant TB (OR = 0.349, P < 0.001); and PZA-resistant TB (OR = 0.076, P < 0.001). In conclusion, pncA mutation typing, with resistance testing and spoligotyping, was useful in identifying a nosocomial TB outbreak and demonstrating its resolution after implementation of infection control measures

Test-retest repeatability of [18F]MC225-PET in rodents:A tracer for imaging of P-gp function

In longitudinal PET studies, animals are repeatedly anesthetized which may affect the repeatability of PET measurements. The aim of this study was to assess the effect of anesthesia on the P-gp function as well as the reproducibility of [18F]MC225 PET scans. Thus, dynamic PET scans with blood sampling were conducted in 13 Wistar rats. Seven animals were exposed to isoflurane anesthesia 1 week before the PET scan ("Anesthesia-exposed" PET). A second group of six animals was used to evaluate the reproducibility of measurements of P-gp function at the blood-brain barrier (BBB) with [18F]MC225. In this group, two PET scans were made with a 1 week interval ("Test" and "Retest" PET). Pharmacokinetic parameters were calculated using compartmental models and metabolite-corrected plasma as an input function. "Anesthesia-exposed" animals showed a 28% decrease in whole-brain volume of distribution (VT) (p < 0.001) compared to "Test", where the animals were not previously anesthetized. The VT at "Retest" also decreased (19%) compared to "Test" (p < 0.001). The k2 values in whole-brain were significantly increased by 18% in "Anesthesia-exposed" (p = 0.005) and by 15% in "Retest" (p = 0.008) compared to "Test". However, no significant differences were found in the influx rate constant K1, which is considered as the best parameter to measure the P-gp function. Moreover, Western Blot analysis did not find significant differences in the P-gp expression of animals not pre-exposed to anesthesia ("Test") or pre-exposed animals ("Retest"). To conclude, anesthesia may affect the brain distribution of [18F]MC225 but it does not affect the P-gp expression or function

The impact of CD160 deficiency on alloreactive CD8 T cell responses and allograft rejection

.CD160 is a member of the immunoglobulin superfamily with a pattern of expression mainly restricted to cytotoxic cells. To assess the functional relevance of the HVEM/CD160 signaling pathway in allogeneic cytotoxic responses, exon 2 of the CD160 gene was targeted by CRISPR/Cas9 to generate CD160 deficient mice. Next, we evaluated the impact of CD160 deficiency in the course of an alloreactive response. To that aim, parental donor WT (wild-type) or CD160 KO (knock-out) T cells were adoptively transferred into non-irradiated semiallogeneic F1 recipients, in which donor alloreactive CD160 KO CD4 T cells and CD8 T cells clonally expanded less vigorously than in WT T cell counterparts. This differential proliferative response rate at the early phase of T cell expansion influenced the course of CD8 T cell differentiation and the composition of the effector T cell pool that led to a significant decreased of the memory precursor effector cells (MPECs) / short-lived effector cells (SLECs) ratio in CD160 KO CD8 T cells compared to WT CD8 T cells. Despite these differences in T cell proliferation and differentiation, allogeneic MHC class I mismatched (bm1) skin allograft survival in CD160 KO recipients was comparable to that of WT recipients. However, the administration of CTLA-4.Ig showed an enhanced survival trend of bm1 skin allografts in CD160 KO with respect to WT recipients. Finally, CD160 deficient NK cells were as proficient as CD160 WT NK cells in rejecting allogeneic cellular allografts or MHC class I deficient tumor cells. CD160 may represent a CD28 alternative costimulatory molecule for the modulation of allogeneic CD8 T cell responses either in combination with costimulation blockade or by direct targeting of alloreactive CD8 T cells that upregulate CD160 expression in response to alloantigen stimulation.S