Photohadronic scenario in interpreting the February-March 2014 flare of 1ES 1011+496

The extraordinary multi-TeV flare from 1ES 1011 +496 during February-March 2014 was observed by MAGIC telescopes for 17 nights and the average spectrum of the whole period has a non-trivial shape. We have used the photohadronic model and a template EBL model to explain the average spectrum which fits well to the flare data. The spectral index $\alpha$ is the only free parameter in our model. We have also shown that the non-trivial nature of the spectrum is due to the change in the behavior of the optical depth above $\sim 600$ GeV $\gamma$-ray energy accompanied with the high SSC flux.Comment: 11 pages, 3 figures, LaTe

Blazar origin of some IceCube events

Recently ANTARES collaboration presented a time dependent analysis to a selected number of flaring blazars to look for upward going muon events produced from the charge current interaction of the muon neutrinos. We use the same list of flaring blazars to look for possible positional correlation with the IceCube neutrino events. In the context of photohadronic model we propose that the neutrinos are produced within the nuclear region of the blazar where Fermi accelerated high energy protons interact with the background synchrotron/SSC photons. Although we found that some objects from the ANTARES list are within the error circles of few IceCube events, the statistical analysis shows that none of these sources have a significant correlation.Comment: Latex file, 6 pages, two columns, 1 Figur

The origin of multi-TeV flares from the nearest blazar Markarian 421

Markarian 421 is a high-peaked BL Lac object and it has undergone many strong outbursts since its discovery as a TeV source in 1992. Markarian 421 has been stud- ied intensively and was observed by various Cherenkov tele- scope arrays ever since. The outbursts of April 2004 observed by the Whipple telescope and of February 2010 by the HESS telescopes are explained well in this work by using the photohadronic model. To account for the attenuation of these high- energy gamma-rays by the extragalactic background light (EBL), we use template EBL models. The intrinsic spectrum of each epoch is different even though the high-energy protons have almost the same spectral index. We observe that this difference in intrinsic spectra is due to the change in the spectral index of the low-energy tail of the synchrotron self Compton (SSC) photons during different epochs of flaring. Our results show that the contemporaneous multiwavelength observations, particularly in the low-energy tail region of the SSC emission of the source, are important in explaining the flaring phenomenon.Comment: Title changed, Single column, 19 pages, 6 figure

Photohadronic emission of VHE gamma rays in blazars and the CTA neutrino target of opportunity program

Blazars are an extremely luminous and highly variable type of AGN, which possess a relativistic jet with a small viewing angle towards the observer. Recent results, such as the 3-sigma spatial and temporal coincidence of TXS~0506+056 with the IceCube neutrino alert IC-170922A, have motivated an ongoing discussion of how these astrophysical sources can produce high-energy neutrinos during a flaring state and which scenario can successfully describe the observed gamma-ray behaviour. In this thesis, the possibility of a hadronic contribution to the very high energy (VHE) gamma-ray emission of blazars, as well as the possible detection of neutrino events, are explored by considering photohadronic interactions in a lepto-hadronic scenario. The model is applied to fit the flaring period of Markarian 421 in 2010, for which a dedicated analysis of Fermi-LAT data from the source was performed in the MeV range (100 MeV - 1 GeV). The fit results were compared with two leptonic models using the Akaike Information Criterion (AIC) test. In all cases, the photohadronic model was favoured as a better fit description in comparison to the one-zone leptonic model. The photohadronic model was also applied to the blazar 4FGL J0658.6+0636, which was found within the 90% localisation region of the IceCube neutrino alert IC-201114A. By analysing 12.3-years of Fermi-LAT data, the periods in which the blazar was detected significantly were identified and studied. For one of these periods, it was found that the photohadronic flaring model results are consistent with the observed gamma-ray behaviour of 4FGL J0658.6+0636 and the IC-201114A is discussed under the photohadronic scenario. These results show the potential of a photohadronic contribution to a lepto-hadronic origin of gamma-ray flux of blazars. The final part of this thesis describes the neutrino and gamma-ray simulations performed for the Neutrino Target of Opportunity (NToO) program for the Cherenkov Telescope Array (CTA). The detection probability with CTA of the gamma-ray flux associated with the simulated IceCube hot-spots for steady neutrino source populations is investigated, and the performance of the CTA Omega configuration array is analysed to predict the potential science reach of the NToO program

Control de Bemisia tabaci utilizando extractos acuosos de albahaca (Ocimum basiliecum). oregano (Lippia qraveolens) y semilla de nim (Azadirachta indica) en frijol de ejote variedad strike

Actualmente la lucha contra los insectos para evitar que bajen los rendimientos de los cultivos es un problema que requiere constante investigación. Para el caso, Bemisia tabaci Genn., se ha constituido en problema serio no sólo para el cultivo de frijol, sino también para tomate, algodón, okra, y otros cultivos comerciales hospederos del insecto. Este problema afecta al pequeño, agricultor y en casos severos la pérdida en la producción alcanza el 100%, debido a que el insecto es vector del virus del mosaico dorado del frijol. Tratando de contribuir con una alternativa de solución se planteó el uso de extractos botánicos, reportados por algunos investigadores y biólogos, como plantas con cierto grado de efecto negativo contra insectos, tal es el caso de albahaca, orégano y semilla del árbol de nim. Se realizó una etapa de laboratorio para definir dosis, una etapa de campo para evaluar en condiciones reales del cultivo y plaga, y una etapa de invernadero para complementar resultados de campo. Pudo determinarse que las dosis de 5.56 y 6.94 kg/ha, tanto de albahaca como también de orégano, y las dosis de 7.5 y 9.0 kg/ha de semilla^de nim, resultaron mejores en laboratorio. Al evaluar estas dosis en campo e invernadero se comprobó que los extractos acuosos de albahaca, orégano y semilla de nim, sí controlaron a Bemis ia tabaci cuando se hicieron observaciones a las 24 horas después de la aplicación. Además el extracto de semilla de nim no permitió completar el desarrollo del ciclo biológico de mosca blanca

Impuesto a los ingresos brutos: "Ave fénix" de la estructura tributaria subnacional

The tax structure includes two aspects: the composition of the public resources and the structure of the taxes in particular. In this paper both questions are studied for the own revenues of the Buenos Aires province. The composition has experienced a notable change throughout the time. Gross receipts taxes replaced the other provincial taxes, especially the property tax. The tax has had important changes along the time and exhibits nowadays a complex structure of tax-rates that is studied theoretical and empirically.La estructura de un sistema tributario comprende dos aspectos: la composición de los recursos públicos y la estructura de los impuestos en particular. En este trabajo se estudian las dos cuestiones para los recursos propios de la Provincia de Buenos Aires. La composición ha experimentado un cambio notable a lo largo del tiempo. Ingresos Brutos ha sustituido a los otros tributos provinciales, especialmente a los que gravan la propiedad inmueble. El impuesto ha tenido cambios importantes a lo largo del tiempo y exhibe actualmente una compleja estructura de alícuotas que se estudia teórica y empíricamente

Influence of Body Composition on Arterial Stiffness in Middle-Aged Adults: Healthy UAL Cross-Sectional Study

Background and objectives: Several anthropometric and body composition parameters have been linked to arterial stiffness (AS) as a biomarker of cardiovascular disease. However, little is known about which of these closely related factors is more strongly associated with AS. The aim of the present study was to analyze the relationship of different anthropometric and body composition parameters with AS in middle-aged adults. Materials and Methods: This cross-sectional study included 186 middle-aged participants (85 women, 101 men; age = 42.8 ± 12.6 years) evaluated as part of the Healthy UAL study, a population study conducted at the University of Almería with the main purpose of analyzing the etiology and risk factors associated with cardio-metabolic diseases. Anthropometric measures included neck, waist, and hip circumferences, as well as the waist-to-height ratio (WHtr). Bioimpedance-derived parameters included fat-free mass index (FFMI), fat mass index (FMI), and percent of body fat (%BF). AS was measured by pulse wave velocity (PWV). The relationships of interest were examined through stepwise regression analyses in which age and sex were also introduced as potential confounders. Results: Neck circumference (in the anthropometric model; R2: 0.889; β: age = 0.855, neck = 0.204) and FFMI (in the bio-impedance model; R2: 0.891; β: age = 0.906, FFMI = 0.199) emerged as significant cross-sectional predictors of AS. When all parameters were included together (both anthropometry and bio-impedance), both neck circumference and FFMI appeared again as being significantly associated with AS (R2: 0.894; β: age = 0.882, FFMI = 0.126, neck = 0.093). Conclusion: It was concluded that FFMI and neck circumference are correlated with AS regardless of potential confounders and other anthropometric and bioimpedance-derived parameters in middle-aged adults