Evaluación probabilista de la amenaza sísmica de Colombia con fines de actualización de la Norma Colombiana de Diseño de Puentes CCP-14

ResumenLa Asociación Colombiana de Ingeniería Sísmica (AIS) ha realizado una actualización del Código Colombiano de Diseño Sismorresistente para Puentes (CCP-14). Entre las diferentes tareas realizadas, ha establecido el valor de los coeficientes de diseño sismorresistente compatibles con la forma funcional del espectro elástico de diseño seleccionado. Para ello, se ha actualizado la evaluación probabilista de la amenaza sísmica a escala nacional y, a partir de ella, se han calculado dichos coeficientes para todo el territorio nacional. Con respecto al último estudio general de amenaza sísmica de Colombia, se dispone de cinco años más de registros de sismicidad y, por consiguiente, de un mejor entendimiento del entorno sísmico colombiano, lo cual ha permitido realizar actualizaciones relacionadas con los parámetros de sismicidad de las fuentes sismogénicas y utilizar relaciones de atenuación de movimiento fuerte calibradas a partir de registros locales. Se presentan los mapas de zonificación sísmica para los tres coeficientes de diseño incluidos en el CCP-14 así como la herramienta gratuita de visualización en línea de los resultados.AbstractA recent update of the Colombian earthquake resistant building code for bridges (CCP-14) was developed by the Colombian Association for Earthquake Engineering (AIS). Among the different tasks developed, the values for the seismic design coefficients, compatible with the functional form of the selected elastic design spectra were established. For that reason an update of the probabilistic seismic hazard assessment was performed from which the seismic design coefficients have been estimated for Colombia. With respect to the latest national seismic hazard assessment, 5 more years of earthquake records and the consequent better understanding of the Colombian seismic environment are included in the analysis by updating the seismicity parameters of the seismogenetic sources and using ground motion prediction equations calibrated with local strong ground motion records. The seismic zonation maps for the three seismic design coefficients included in the CCP-14 are presented as well as the free online results visualization too

Modelización probabilista de efectos de sitio en ciudades y su aplicación en Bogotá

A methodology for assessing site effects in cities is presented, which is based on the geometry of the prevailing geological formations and their relation to soft soil deposits. Based on a geological interpretation for the area of the city, the elevation (above sea level) of geological contacts is defined, and a three-dimensional geometric model of the subsoil of the city is obtained. The geotechnical information available is used to map soil types to the geometric model. The static and dynamic characteristics of the soil are defined as random variables and their probability moments are calculated using statistics on the geotechnical data available. A computational rectangular grid must be defined over the city and for each node synthetic stratigraphies are constructed with geotechnical parameters obtained following their probability distributions. The dynamic response is calculated for each node of the grid, by a 1D nonlinear analysis (linear equivalent) using a set of Fourier amplitude spectra generated at bedrock level using a source spectrum model, for different combinations of moment magnitude and rupture distance. Site-specific attenuation functions are generated and used to calculate seismic hazard at surface level. Uniform hazard spectra for 475 years return period are obtained. From these spectra harmonized design spectra to the NSR 10 are generated by random search of Fa and Fv parameters to ensure optimum fit. Following this methodology a site effects model for the city of Bogotá, Colombia, is constructed. This is used to exemplify trhee main direct application: i) obtaining transfer functions of the response spectrum for risk assessment, ii) generating Shake- Maps for emergency response purposes, and iii) the seismic microzonation of the city and obtaining elastic seismic-resistant design spectra

Sensitive spectrophotometric determination of hydrogen peroxide in aqueous samples from advanced oxidation processes: Evaluation of possible interferences

Hydrogen peroxide (H2O2) determination in real watersamples was carried out in a simple and sensitiveway. The resulting optimal operating conditions froma 23 full factorial experimental design were 450 nm, 50mm and 6x10-3 M for the absorption wavelength, thequartz cell path length and the final concentration ofthe ammonium monovanadate solution, respectively;allowing the quantification of H2O2 up to 2.94x10-3mM. The proposed analytical method was validatedand the effect of the background matrix was investigated,obtaining a selective method. Additionally, thedeveloped analytical method was applied for studyingthe evolution of H2O2 in the decontamination of watercontaining 6.73x10-5 mM of anthracene and 1.19x10-5mM of benzo[a]pyrene using the UV/H2O2 system. Itwas found that the optimal H2O2 level enabling about45% of mineralisation and a removal of the targetpolycyclic aromatic hydrocarbons higher than 99%was 2.94x10-1 mM, remaining approximately 1.47x10-1 mM of H2O2 after 90 min of treatment

Biogeochemical markers across a pollution gradient in a Patagonian estuary: A multidimensional approach of fatty acids and stable isotopes

A combined approach merging stable isotopes and fatty acids was applied to study anthropogenic pollution in the Río Negro estuary. Fatty acid markers of vegetal detritus indicated considerable allochthonous inputs at freshwater sites. Correlative evidence of diatom fatty acids, δ13C, chlorophyll and particulate organic matter suggested the importance of diatoms for the autochthonous organic matter production at the river mouth. Low δ15N values (~0�) and high fatty acid 18:1(n-7) concentrations in the suspended particulate matter, in combination with the peaks of coliforms and ammonium, indicated a strong impact of untreated sewage discharge. The 15N depletion was related to oxygen-limited ammonification processes and incorporation of 15N depleted ammonium to microorganisms. This work demonstrates that the combined use of lipid and isotopic markers can greatly increase our understanding of biogeochemical factors and pollutants influencing estuaries, and our findings highlight the urgent need for water management actions to reduce eutrophication

Moving forward through the in silico modeling of tuberculosis: a further step with UISS-TB

Background In 2018, about 10 million people were found infected by tuberculosis, with approximately 1.2 million deaths worldwide. Despite these numbers have been relatively stable in recent years, tuberculosis is still considered one of the top 10 deadliest diseases worldwide. Over the years, Mycobacterium tuberculosis has developed a form of resistance to first-line tuberculosis treatments, specifically to isoniazid, leading to multi-drug-resistant tuberculosis. In this context, the EU and Indian DBT funded project STriTuVaD—In Silico Trial for Tuberculosis Vaccine Development—is supporting the identification of new interventional strategies against tuberculosis thanks to the use of Universal Immune System Simulator (UISS), a computational framework capable of predicting the immunity induced by specific drugs such as therapeutic vaccines and antibiotics. Results Here, we present how UISS accurately simulates tuberculosis dynamics and its interaction within the immune system, and how it predicts the efficacy of the combined action of isoniazid and RUTI vaccine in a specific digital population cohort. Specifically, we simulated two groups of 100 digital patients. The first group was treated with isoniazid only, while the second one was treated with the combination of RUTI vaccine and isoniazid, according to the dosage strategy described in the clinical trial design. UISS-TB shows to be in good agreement with clinical trial results suggesting that RUTI vaccine may favor a partial recover of infected lung tissue. Conclusions In silico trials innovations represent a powerful pipeline for the prediction of the effects of specific therapeutic strategies and related clinical outcomes. Here, we present a further step in UISS framework implementation. Specifically, we found that the simulated mechanism of action of RUTI and INH are in good alignment with the results coming from past clinical phase IIa trials

Measurement of the Bs0→J/ψKS0B_s^0\to J/\psi K_S^0 branching fraction

The $B_s^0\to J/\psi K_S^0$ branching fraction is measured in a data sample corresponding to 0.41$fb^{-1}$ of integrated luminosity collected with the LHCb detector at the LHC. This channel is sensitive to the penguin contributions affecting the sin2$\beta$ measurement from $B^0\to J/\psi K_S^0$ The time-integrated branching fraction is measured to be $BF(B_s^0\to J/\psi K_S^0)=(1.83\pm0.28)\times10^{-5}$. This is the most precise measurement to date

Model-independent search for CP violation in D0→K−K+π−π+ and D0→π−π+π+π− decays

A search for CP violation in the phase-space structures of D0 and View the MathML source decays to the final states K−K+π−π+ and π−π+π+π− is presented. The search is carried out with a data set corresponding to an integrated luminosity of 1.0 fb−1 collected in 2011 by the LHCb experiment in pp collisions at a centre-of-mass energy of 7 TeV. For the K−K+π−π+ final state, the four-body phase space is divided into 32 bins, each bin with approximately 1800 decays. The p-value under the hypothesis of no CP violation is 9.1%, and in no bin is a CP asymmetry greater than 6.5% observed. The phase space of the π−π+π+π− final state is partitioned into 128 bins, each bin with approximately 2500 decays. The p-value under the hypothesis of no CP violation is 41%, and in no bin is a CP asymmetry greater than 5.5% observed. All results are consistent with the hypothesis of no CP violation at the current sensitivity

Absolute luminosity measurements with the LHCb detector at the LHC

Absolute luminosity measurements are of general interest for colliding-beam experiments at storage rings. These measurements are necessary to determine the absolute cross-sections of reaction processes and are valuable to quantify the performance of the accelerator. Using data taken in 2010, LHCb has applied two methods to determine the absolute scale of its luminosity measurements for proton-proton collisions at the LHC with a centre-of-mass energy of 7 TeV. In addition to the classic "van der Meer scan" method a novel technique has been developed which makes use of direct imaging of the individual beams using beam-gas and beam-beam interactions. This beam imaging method is made possible by the high resolution of the LHCb vertex detector and the close proximity of the detector to the beams, and allows beam parameters such as positions, angles and widths to be determined. The results of the two methods have comparable precision and are in good agreement. Combining the two methods, an overall precision of 3.5% in the absolute luminosity determination is reached. The techniques used to transport the absolute luminosity calibration to the full 2010 data-taking period are presented.Comment: 48 pages, 19 figures. Results unchanged, improved clarity of Table 6, 9 and 10 and corresponding explanation in the tex

Search for the lepton-flavor-violating decays Bs0→e±μ∓ and B0→e±μ∓

A search for the lepton-flavor-violating decays Bs0→e±μ∓ and B0→e±μ∓ is performed with a data sample, corresponding to an integrated luminosity of 1.0  fb-1 of pp collisions at √s=7  TeV, collected by the LHCb experiment. The observed number of Bs0→e±μ∓ and B0→e±μ∓ candidates is consistent with background expectations. Upper limits on the branching fractions of both decays are determined to be B(Bs0→e±μ∓)101  TeV/c2 and MLQ(B0→e±μ∓)>126  TeV/c2 at 95% C.L., and are a factor of 2 higher than the previous bounds

Measurement of the ratio of branching fractions BR(B0 -> K*0 gamma)/BR(Bs0 -> phi gamma) and the direct CP asymmetry in B0 -> K*0 gamma

The ratio of branching fractions of the radiative B decays B0 -> K*0 gamma and Bs0 phi gamma has been measured using an integrated luminosity of 1.0 fb-1 of pp collision data collected by the LHCb experiment at a centre-of-mass energy of sqrt(s)=7 TeV. The value obtained is BR(B0 -> K*0 gamma)/BR(Bs0 -> phi gamma) = 1.23 +/- 0.06(stat.) +/- 0.04(syst.) +/- 0.10(fs/fd), where the first uncertainty is statistical, the second is the experimental systematic uncertainty and the third is associated with the ratio of fragmentation fractions fs/fd. Using the world average value for BR(B0 -> K*0 gamma), the branching fraction BR(Bs0 -> phi gamma) is measured to be (3.5 +/- 0.4) x 10^{-5}. The direct CP asymmetry in B0 -> K*0 gamma decays has also been measured with the same data and found to be A(CP)(B0 -> K*0 gamma) = (0.8 +/- 1.7(stat.) +/- 0.9(syst.))%. Both measurements are the most precise to date and are in agreement with the previous experimental results and theoretical expectations.Comment: 21 pages, 3 figues, 4 table