Characterization of the blue emission of Tm/Er co-implanted GaN

Comparative studies have been carried out on the cathodoluminescence (CL) and photoluminescence (PL) properties of GaN implanted with Tin and GaN co-implanted with Tin and a low concentration of Er. Room temperature CL spectra were acquired in an electron probe microanalyser to investigate the rare earth emission. The room temperature CL intensity exhibits a strong dependence on the annealing temperature of the implanted samples. The results of CL temperature dependence are reported for blue emission (similar to 477 nm) which is due to intra 4f-shell electron transitions ((1)G(4)-> H-3(6)) associated with Tm3+ ions. The 477 nm blue CL emission is enhanced strongly as the annealing temperature increases up to 1200 degrees C. Blue PL emission has also been observed from the sample annealed at 1200 degrees C. To our knowledge, this is the first observation of blue PL emission from Tin implanted GaN samples. Intra-4f transitions from the D-1(2) level (similar to 465 nm emission lines) of Tm3+ ions in GaN have been observed in GaN:Tm films at temperatures between 20-200 K. We will discuss the temperature dependent Tm3+ emission in both GaN:Tm,Er and GaN:Tm samples

Obesity, diabetes and OSAS induce of sleep disorders: Exercise as therapy

Sleep is an integral part of good health. Sleep disorders and variations in sleep habits are associated with a low-grade inflammatory status, which may be either a cause or consequence of other conditions, including obesity, diabetes and cardiovascular disease. Several strategies are available to counteract these conditions including continuous positive airway pressure (CPAP), pharmacological and nutritional interventions, and even surgery. At present, our group is investigating the effect of chronic endurance exercise on sleep alterations

Resonant Lepton-Gluon Collisions at the Large Hadron Collider

We study the lepton-induced resonant production of color-adjoint leptons (leptogluons) at the LHC employing the lepton parton density function of the proton. We demonstrate that this production mechanism can be useful to extend the LHC ability to search for leptogluons beyond purely quark/gluon initiated production processes up to ~ 3.5 TeV leptogluon masses and O(1) TeV compositeness scales. Discerning leptogluons from scalar and vector leptoquarks is also possible in this channel, given a data sample containing the order of 100 signal events. We argue that the resonant channel can be combined with leptogluon pair and associated leptogluon-lepton productions to boost exclusion limits and discovery prospects at the LHC.Comment: 15 pages, 8 figure

Same-Sign Taus Signatures of Maximally Flavor-Violating Scalars at the LHC

We explore single and double flavor-violating scalars (flavons) production at the 13 and 14 TeV LHC in an effective field theory formulation where flavons always change the flavor of Standard Model fermions. When those scalars couple to mass, their flavor-changing couplings to top quarks and tau leptons are favored. Focusing on the mass region below the top quark mass, we find couplings that fit the muon and electron $(g-2)$ discrepancies and avoid several current experimental constraints. We determine the potential of the LHC to exclude or discover such a new physics scenario with clean signatures consisting of same-sign tau leptons and the simultaneous observation of resonances in the tau plus electron or muon invariant mass. We found that in the double production mode, effective couplings down to order $10^{-2}$ TeV$^{-1}$ can be probed for flavon masses in the 10-170 GeV range at the HL-LHC at 14 TeV, but couplings down to 0.1 TeV$^{-1}$ can be excluded at 95\% confidence level with data collected by the 13 TeV LHC in the same mass interval.Comment: 32 pages, 12 figures, 2 table

Urban Operation Threat Assessment after a Multistage Radiological Dispersive Device Attack

The urban environment may be a relevant setting for special military operations. Due to the options offered by urban infrastructure, this environment can be an essential catalyst for the proliferation of local asymmetric actions. These actions are triggered by extremist groups offering resistance to regular troops. Improvised weapons such as radiological dispersive devices (RDD) can be used to provoke even more threatening situations by increasing the risks of operations. This study is directed, via computer simulation using the Hot Spot Health Physics code, to a hypothetical context where a multistage RDD (RDD-M) is triggered in two non-simultaneous phases. This non-linear triggering causes overlapping contamination and impacts the coping strategy and the projections of variations in the size of the potentially affected population. In this study, the primary consideration is the contamination carried out at such a level that the association between human exposure and deterministic effects is feasible. The exposure to high doses of radiation at short distances about the triggering location of the device. The simulated data show that the threats are leveraged, and the environmental variables have a high value when assessing the criticality of the situation and establishing effective countermeasures

Adaptive response of neonatal sepsis-derived Group B Streptococcus to bilirubin

This work was funded by the Neonatal Unit Endowment Fund, Aberdeen Maternity Hospital. RH is funded by a career researcher fellowship from NHS Research Scotland. SG was funded by the MRC Flagship PhD programme. We are grateful for the support of Dr Phil Cash and Aberdeen Proteomics, at University of Aberdeen, in completing this project. Supplementary information accompanies this paper at https://doi.org/10.1038/s41598-018-24811-3.Peer reviewedPublisher PD

Ciclo de vida y dinámica poblacional de la enigmática tanaide Chondrochelia dubia (Tanaidacea: Leptocheliidae) en un lecho de algas tropicales

The present study describes the population dynamics and life history parameters of the enigmatic tanaid Chondrochelia dubia collected in Paiva Beach, tropical coast of Brazil. The region was impacted by a large, unexpected oil spill from August to October 2019. Samples were taken monthly between July 2019 and July 2020 in beds of the red seaweed Jania capillacea. The abundance of individuals was negatively correlated with monthly rainfall, with higher abundances in drier months. There was an unexpected significant drop in abundance in September, possibly caused by contact with the crude oil, but the population recovered fully within two months. The parameters of the von Bertallanfy growth equation, calculated for the first time for the species, were Linf=5.26 mm; k=3.36 year–1; t0=0.0. Compared with other studies, the specimens are very small (2.04 ± 0.95 mm in length), females reach sexual maturity very early (L50=2.3 mm), and natural mortality is high (Z=M=5.77 year–1), indicating an opportunistic life strategy. This study reinforces the bioindication potential of C. dubia and the use of bootstrapped length-based methods to estimate key population parameters in small marine invertebrates.El presente estudio describió la dinámica poblacional y los parámetros del ciclo de vida del enigmático tanaidáceo Chondrochelia dubia recolectado en la playa de Paiva, costa tropical de Brasil. La región se vio afectada por un gran derrame de petróleo inesperado de agosto a octubre de 2019. Se tomaron muestras mensualmente entre julio de 2019 y julio de 2020 en lechos de algas rojas Jania capillacea. La abundancia de individuos se correlacionó negativamente con la precipitación mensual, con mayor abundancia en los meses más secos. Hubo una inesperada caída significativa de la abundancia en septiembre, posiblemente causada por el contacto con el petróleo crudo, sin embargo, la población se recuperó por completo en dos meses. Los parámetros de la ecuación de crecimiento de von Bertallanfy, calculados por primera vez para la especie, fueron: Linf=5.26 mm; k=3.36 año–1; t0=0,0. En comparación con otros estudios, los ejemplares son muy pequeños (2.04 ± 0.95 mm de longitud), las hembras alcanzan la madurez sexual muy temprano (L50=2.3 mm), y la mortalidad natural es relativamente alta (Z=M=5.77 año–1), lo que indica una estrategia de vida oportunista. Este estudio refuerza el potencial de bioindicación de C. dubia y el uso de métodos bootstrap basados en la longitud para estimar parámetros de población clave en pequeños invertebrados marinos