Investigation of EBT3 radiochromic film’s response to humidity

Purpose: The aim of this work is to investigate the effects of immersing EBT3 radiochromic film in water and to evaluate its contribution to the total uncertainty in dose determination. Materials and methods: We used 3 cm 9 3 cm EBT3 radiochromic films irradiated in the range of 0–70 Gy to study the impact of water immersion on the change in net optical density. These films were placed in a water container for a period of 24 h. The net optical density was measured before (0 h) and after of the immersion in water (1, 3, 6, 12, 18, and 24 h). The absorbance spectrum of the EBT3 radiochromic film was measured at 0 h and 24 h after immersion in water. The uncertainty in dose determination due to the effects of keeping the EBT3 radiochromic film submerged in water at 0, 1, and 24 h were recorded in the red, green, and blue channels. Results: We observed an increase in the net optical density as an effect on the film due to its immersion in water. The penetration of the water at the edges of the radiochromic film was observed to be a function of time during which the film remained in the water. On the other hand, the penetration of water at the edges of the film was found to be independent of irradiation dose. Conclusions: EBT3 radiochromic film is found more resistant to water penetration through the edges than its predecessors. However, there is evidence that suggest that liquid water damage the Nylon cover layer of the film by changing its optical properties. Therefore, it is recommended to build a new calibration curve for radiochromic films for a specific situation involving dose measurements in liquid water.UAEMex INN

Información climática asociada a estaciones productivas para el ajuste de modelos estadísticos de sistemas bovinos bajo condiciones extensivas

Artículo de investigación publicado en revista internacional indizada.El objeto de este estudio fue desarrollar una metodología para clasificar épocas de nacimiento (EN) y evaluar su impacto en indicadores productivos al compararlas con un método tradicional de clasificación. Con información meteorológica, se generó un índice de aridez para clasificar las EN. Las EN propuesta y tradicional se compararon, incluyéndolas como grupo contemporáneo (GC= hato, sexo, año y EN) a modelos de evaluación genética de caracteres de peso vivo. Fueron estimados los componentes de varianza y valores genéticos (DEP) con sus exactitudes. La clasifica- ción propuesta explicó mayor variabilidad que la clasificación tradicional (≥9,8%). Los parámetros genéticos mostraron cambios importantes, siendo los más evidentes en peso al destete. Los modelos fueron diferentes de acuerdo a la prueba de razón de verosimilitudes (P<0,01). Se observó una mejora de estructura en los GC. Para los dos caracteres evaluados las correlaciones entre los valores genéticos de los animales fueron diferentes, lo que indica cambio en la jerarquización. Este método de clasificación de EN puede ayudar a mejorar el ajuste de modelos estadísticos en condiciones en las que exista la información climática necesaria para su implementación.Los autores agradecen al Consejo Nacional de Cien- cia y Tecnología por el financiamiento del proyecto CB168207 y al Instituto Politécnico Nacional a través del proyecto SIP20150746

Análisis de los espectros de absorción de las películas radiocrómicas EBT2 y EBT3

Objetivo: Analizar los espectros de absorción neta de las películas radiocrómicas EBT2 y EBT3 para describir su influencia en el comportamiento de las curvas de dosis-respuesta. Metodología: Las películas se irradiaron en un acelerador lineal de 6 MV. La obtención de los espectros de absorción neta se realizó con espectrofotómetro UV/VIS. Las curvas de dosis-respuesta se obtuvieron con un escáner, un láser He-Ne y un espectrofotómetro. Resultados: El espectro de absorción de las EBT2 muestra tres bandas de absorción centradas que conservan la posición y aumentan su intensidad en función de la dosis, sin embargo, este comportamiento no se observa en las películas EBT3. La curva dosis-respuesta muestra la máxima sensibilidad utilizando el espectrofotómetro, pero no muestra un comportamiento definido. Implicaciones: Generación de nuevos conocimientos para la creación de nuevos sistemas ópticos capaces de amplificar la sensibilidad de la respuesta de las películas. Originalidad: Mostrar la correlación entre los espectros de absorción neta y su influencia en las curvas dosis-respuesta en tres diferentes sistemas ópticos. Conclusiones: El comportamiento de los espectros de absorción aunado al comportamiento de las curvas dosis-respuesta nos ayuda a descartar el uso de sistemas ópticos que no garanticen un uso clínico confiable

Bactericidal effect of silver nanoparticles against propagation of Clavibacter michiganensis infection in Lycopersicon esculentum Mill

This study explored the use of silver nanoparticle as a bactericidal against the propagation of Clavibacter michiganensis onto tomatoes (Lycopersicon esculentum Mill). In Mexico, tomato production covers about 73% of the total vegetable production but it is affected by outbreak of bacteria canker caused by Clavibacter michiganensis subspecies michiganensis (Cmm). Silver ions possess inhibitor properties, bactericides and high specter antimicrobials. In this study, 6 groups of culture were prepared using 6 different petri dishes where silver nanoparticles of varying concentrations (120, 84, 48, 24, 12 and 0 μg) were added. Furthermore, each group was observed for 20 min, 1, 2, 12 and 24 h. The optimum concentration is 84 μg, which shows an average of 2 Cmm colonies after 20 min. Further increase to 120 μg shows no significant change. However, the average colonies was observed for 48 μg after 1, 2, 12, and 24 h. The obtained results indicate that silver nanoparticles are a promising inhibitor, bactericide and high a specter antimicrobial for treatment or prevention of Cmm

Results obtained from the multiple geodetic observations at Lorca (Murcia, Spain) subsidence area

Trabajo presentado en el AGU (American Geophysical Union) Fall Meeting: Advancing Earth and Space Science, celebrado en Washington D.C. (Estados Unidos), del 10 al 14 de diciembre de 2018The Lorca region, located in the Alto Guadalentín Basin, southern Spain, shows the highest subsidence rates recorded in Europe (about 10 cm/yr). It is produced by a long-term aquifer exploitation (González and Fernández, 2011; Bonì et al., 2014). This process has been studied in various works using interferometric synthetic aperture radar (InSAR) with images acquired from different satellites (ERS and ENVISAT radar data spanning the 1992 – 2007 period; ALOS PALSAR data for the period 2007–2010; and COSMO-SkyMed data for the period 2011–2012). González et al. (2012) established a relationship between the crustal unloading produced by the groundwater overexploitation and the stress change on the regional active tectonic faults in relation with the May 2008 Lorca earthquake. Those previous studies, based on InSAR and using either ascending or descending acquisitions, assumed that the surface displacement direction is entirely vertical. However, it is important to obtain the complete 3D motion field in order to perform a correct interpretation of the observations, as well as to carry out an advanced numerical model of the aquifer evolution, to be considered for sustainable management plans of groundwater resources and hazard assessments. To achieve this goal, GNSS surveys have been carried out from 2015 to 2018, showing the regional 3D displacement field associated to the exploitation of the aquifer (Prieto et al., 2016; Fernández et al. 2017). Also, simultaneous ascending and descending InSAR observations have been used, along with structural gravimetry (Camacho et al., 2015) and microgravity to study the subsidence area in a more complete geodetic way. We present the results obtained from all those techniques, their comparison, and the interpretation results using different inversion techniques (Tiampo et al., 2011; Camacho et al., 2011, 2015; Cannavò et al., 2015).Peer reviewe

Hyperdominance in Amazonian Forest Carbon Cycling

While Amazonian forests are extraordinarily diverse, the abundance of trees is skewed strongly towards relatively few ‘hyperdominant’ species. In addition to their diversity, Amazonian trees are a key component of the global carbon cycle, assimilating and storing more carbon than any other ecosystem on Earth. Here we ask, using a unique data set of 530 forest plots, if the functions of storing and producing woody carbon are concentrated in a small number of tree species, whether the most abundant species also dominate carbon cycling, and whether dominant species are characterized by specific functional traits. We find that dominance of forest function is even more concentrated in a few species than is dominance of tree abundance, with only ≈1% of Amazon tree species responsible for 50% of carbon storage and productivity. Although those species that contribute most to biomass and productivity are often abundant, species maximum size is also influential, while the identity and ranking of dominant species varies by function and by region

Clonal chromosomal mosaicism and loss of chromosome Y in elderly men increase vulnerability for SARS-CoV-2

The pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2, COVID-19) had an estimated overall case fatality ratio of 1.38% (pre-vaccination), being 53% higher in males and increasing exponentially with age. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, we found 133 cases (1.42%) with detectable clonal mosaicism for chromosome alterations (mCA) and 226 males (5.08%) with acquired loss of chromosome Y (LOY). Individuals with clonal mosaic events (mCA and/or LOY) showed a 54% increase in the risk of COVID-19 lethality. LOY is associated with transcriptomic biomarkers of immune dysfunction, pro-coagulation activity and cardiovascular risk. Interferon-induced genes involved in the initial immune response to SARS-CoV-2 are also down-regulated in LOY. Thus, mCA and LOY underlie at least part of the sex-biased severity and mortality of COVID-19 in aging patients. Given its potential therapeutic and prognostic relevance, evaluation of clonal mosaicism should be implemented as biomarker of COVID-19 severity in elderly people. Among 9578 individuals diagnosed with COVID-19 in the SCOURGE study, individuals with clonal mosaic events (clonal mosaicism for chromosome alterations and/or loss of chromosome Y) showed an increased risk of COVID-19 lethality

Annual Conference on Formative Research on EFL. Practices thar inspire change.

The conference papers of the Annual Conference on Formative Research on EFL. Practices thar inspire change collect pedagogical experiences, research reports, and reflections about social issues, language teaching, teaching training, interculturality under the panorama of the Covid-19 pandemic. Each paper invites the reader to implement changes in their teaching practice through disruptive pedagogies, reflect on the social and emotional consequences of the lockdown, new paths for teacher training and different approaches for teaching interculturality. We expect to inspire new ways to train pre-service teachers and teach languages in this changing times

The impact of surgical delay on resectability of colorectal cancer: An international prospective cohort study

AIM: The SARS-CoV-2 pandemic has provided a unique opportunity to explore the impact of surgical delays on cancer resectability. This study aimed to compare resectability for colorectal cancer patients undergoing delayed versus non-delayed surgery. METHODS: This was an international prospective cohort study of consecutive colorectal cancer patients with a decision for curative surgery (January-April 2020). Surgical delay was defined as an operation taking place more than 4 weeks after treatment decision, in a patient who did not receive neoadjuvant therapy. A subgroup analysis explored the effects of delay in elective patients only. The impact of longer delays was explored in a sensitivity analysis. The primary outcome was complete resection, defined as curative resection with an R0 margin. RESULTS: Overall, 5453 patients from 304 hospitals in 47 countries were included, of whom 6.6% (358/5453) did not receive their planned operation. Of the 4304 operated patients without neoadjuvant therapy, 40.5% (1744/4304) were delayed beyond 4 weeks. Delayed patients were more likely to be older, men, more comorbid, have higher body mass index and have rectal cancer and early stage disease. Delayed patients had higher unadjusted rates of complete resection (93.7% vs. 91.9%, P = 0.032) and lower rates of emergency surgery (4.5% vs. 22.5%, P < 0.001). After adjustment, delay was not associated with a lower rate of complete resection (OR 1.18, 95% CI 0.90-1.55, P = 0.224), which was consistent in elective patients only (OR 0.94, 95% CI 0.69-1.27, P = 0.672). Longer delays were not associated with poorer outcomes. CONCLUSION: One in 15 colorectal cancer patients did not receive their planned operation during the first wave of COVID-19. Surgical delay did not appear to compromise resectability, raising the hypothesis that any reduction in long-term survival attributable to delays is likely to be due to micro-metastatic disease

Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research