Magnetic response dependence of ZnO based thin films on Ag doping and processing architecture

Multifunctional and multiresponsive thin films are playing an increasing role in modern technology. This work reports a study on the magnetic properties of ZnO and Ag-doped ZnO semiconducting films prepared with a zigzag-like columnar architecture and their correlation with the processing conditions. The films were grown through Glancing Angle Deposition (GLAD) co-sputtering technique to improve the induced ferromagnetism at room temperature. Structural and morphological characterizations have been performed and correlated with the paramagnetic resonance measurements, which demonstrate the existence of vacancies in both as-cast and annealed films. The magnetic measurements reveal changes in the magnetic order of both ZnO and Ag-doped ZnO films with increasing temperature, showing an evolution from a paramagnetic (at low temperature) to a diamagnetic behavior (at room temperature). Further, the room temperature magnetic properties indicate a ferromagnetic order even for the un-doped ZnO film. The results open new perspectives for the development of multifunctional ZnO semiconductors, the GLAD co-sputtering technique enables the control of the magnetic response, even in the un-doped semiconductor materials.The Brazilian agencies CNPq, CAPES partially supports the research. From Portugal side, this work was supported by the Portuguese Foundation for Science and Technology (FCT) in the framework of the Strategic Funding UID/FIS/04650/2020 and the junior research contract (A.F.). Financial support from the Basque Government Industry Department under the ELKARTEK. HAZITEK and PIBA programs is also acknowledged

Comparative In Vitro Activity of Ceftolozane/Tazobactam against Clinical Isolates of Pseudomonas aeruginosa and Enterobacterales from Five Latin American Countries

Background: Ceftolozane/tazobactam (C/T) is a combination of an antipseudomonal oxyiminoaminothiazolyl cephalosporin with potent in vitro activity against Pseudomonas aeruginosa and tazobactam, a known β-lactamase inhibitor. The aim of this study was to evaluate the activity of C/T against clinical isolates of P. aeruginosa and Enterobacterales collected from five Latin American countries between 2016 and 2017, before its clinical use in Latin America, and to compare it with the activity of other available broad-spectrum antimicrobial agents. Methods: a total of 2760 clinical isolates (508 P. aeruginosa and 2252 Enterobacterales) were consecutively collected from 20 hospitals and susceptibility to C/T and comparator agents was tested and interpreted following the current guidelines. Results: according to the CLSI breakpoints, 68.1% (346/508) of P. aeruginosa and 83.9% (1889/2252) of Enterobacterales isolates were susceptible to C/T. Overall, C/T demonstrated higher in vitro activity than currently available cephalosporins, piperacillin/tazobactam and carbapenems when tested against P. aeruginosa, and its performance in vitro was comparable to fosfomycin. When tested against Enterobacterales, it showed higher activity than cephalosporins and piperacillin/tazobactam, and similar activity to ertapenem. Conclusions: these results show that C/T is an active β-lactam agent against clinical isolates of P. aeruginosa and Enterobacterales.Fil: García Betancur, Juan Carlos. Universidad El Bosque;Fil: De La Cadena, Elsa. Universidad El Bosque;Fil: Mojica, María F.. Universidad El Bosque; . Case Western Reserve University; Estados UnidosFil: Hernández Gómez, Cristhian. Universidad El Bosque;Fil: Correa, Adriana. Universidad Santiago de Cali; ColombiaFil: Radice, Marcela Alejandra. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad de Buenos Aires. Facultad de Farmacia y BioquÍmica. Instituto de Investigaciones En Bacteriología y Virología Molecular (IBaViM); ArgentinaFil: Castañeda Méndez, Paulo. Fundacion Clinica Medica Sur; MéxicoFil: Jaime Villalon, Diego A.. Fundacion Clinica Medica Sur; MéxicoFil: Gales, Ana C.. Universidade Federal de Sao Paulo; BrasilFil: Munita, José M.. Universidad del Desarrollo; ChileFil: Villegas, María Virginia. Universidad El Bosque

Tuberculosis y vitamina D: una relación intrigante

La tuberculosis permanece como la enfermedad infecciosa que más muertes ha causado a lo largo de la historia de la existencia humana, sin poderse aún lograr su control. En años recientes ha emergido un cúmulo importante de evidencia clínica acerca de la función de la vitamina D (calcitriol o 1,25 hidroxivitamina D) en un papel que va más allá de la homeostasis del calcio. Su papel en el sistema inmunológico es muy interesante vinculando su déficit como un factor de riesgo contribuyente y así mismo fisiopatológico en un gran número de enfermedades autoinmunes e infecciosas. Dentro de éstas se destaca la tuberculosis, enfermedad endémica en nuestro país y en la cual el déficit de dicho compuesto (vitamina D) crea un factor de riesgo para desarrollar esta enfermedad en su forma activa. Presentamos una revisión detallada de los estudios que explican el papel de la vitamina D en la susceptibilidad para el desarrollo de tuberculosis y los resultados de los estudios clínicos de suplencia de la misma publicados a la fecha

ECOLOGÍA TÉRMICA DE UNA POBLACIÓN DE LA LAGARTIJA SCELOPORUS GRAMMICUS (IGUANIDAE: PHRYNOSOMATINAE) QUE OCURRE EN LA ZONA CENTRO-ORIENTE DE LA CIUDAD DE MÉXICO

The thermal ecology of the lizard, Sceloporus grammicus in Mexico City was studied. Mean body temperature (Tb) was 31.43 ± 0.1 ºC. Body temperature was significantly and positively related to air temperature (Ta: n = 147, r = 0.451, P < 0.001; Tb = 27.529 + 0.195 Ta) and substrate temperature (Ts: n = 147, r = 0.482, P < 0.001; Tb = 27.315 + 0.199 Ts) occupied by the lizards. The body temperature was different between males and females (ANCOVA with Ts as the covariate F1,146 = 8.71, P = 0.003) and between pregnant females and unpregnant females as well (ANCOVA with Ts as the covariate F1,91 = 18.81 P < 0.001). These results suggested that S. grammicus is a lizard with active thermoregulation and that reproductive status can influence the thermoregulatory strategy of females.Estudiamos la ecología térmica de la lagartija Sceloporus grammicus que habita en la región central de la Ciudad de México. La temperatura corporal (Tc) promedio para estos organismos fue de 31.43 ± 0.1 °C. La Tc de Sceloporus grammicus estuvo positiva y significativamente correlacionada con la temperatura del aire [Ta] (n =147, r = 0.451, P < 0.001; Tc 27.529 + 0.195 Ta) y con la temperatura del sustrato [Ts] (n = 147, r = 0.482, P < 0.001; Tc = 27.315 + 0.199 Ts) donde se encontraban. Observamos diferencias significativas entre la temperatura corporal de machos y hembras (ANCOVA con la Ts como covariable F1,146 = 8.71, P = 0.003), así como en la temperatura corporal presentada entre hembras preñadas y no preñadas (ANCOVA con la Ts como covariable F1,91 = 18.81 P < 0.001). Estos resultados sugieren que S. grammicus presenta una tendencia hacia la termorregulación activa y que el estadio reproductivo de las hembras puede influir su estrategia termorreguladora

Testing spatial noncommutativiy via the Aharonov-Bohm effect

The possibility of detecting noncommutative space relics is analyzed using the Aharonov-Bohm effect. We show that, if space is noncommutative, the holonomy receives non-trivial kinematical corrections that will produce a diffraction pattern even when the magnetic flux is quantized. The scattering problem is also formulated, and the differential cross section is calculated. Our results can be extrapolated to high energy physics and the bound $\theta \sim [ 10 {TeV}]^{-2}$ is found. If this bound holds, then noncommutative effects could be explored in scattering experiments measuring differential cross sections for small angles. The bound state Aharonov- Bohm effect is also discussed.Comment: 16 pp, Revtex 4, 2 fig, new references added. To appear in PR