Low red-shift effects of local structure on the Hubble parameter in presence of a cosmological constant

In order to estimate the effects of local structure on the Hubble parameter we calculate the low-redshift expansion for $H(z)$ and $\frac{\delta H}{H}$ for an observer at the center of a spherically symmetric matter distribution in presence of a cosmological constant. We then test the accuracy of the formulae comparing them with fully relativistic non perturbative numerical calculations for different cases for the density profile. The low red-shift expansion we obtain gives results more precise than perturbation theory since is based on the use of an exact solution of Einstein's field equations. For larger density contrasts the low red-shift formulae accuracy improves respect to the perturbation theory accuracy because the latter is based on the assumption of a small density contrast, while the former does not rely on such assumption. The formulae can be used to take into account the effects on the Hubble expansion parameter due to the monopole component of the local structure. If the $H(z)$ observations will show deviations from the $\Lambda CDM$ prediction compatible with the formulae we have derived, this could be considered an independent evidence of the existence of a local inhomogeneity, and the formulae could be used to determine the characteristics of this local structure.Comment: 14 pages, 4 figure

Reconstructing the metric of the local Universe from number counts observations

Number counts observations available with new surveys such as the Euclid mission will be an important source of information about the metric of the Universe. We compute the low red-shift expansion for the energy density and the density contrast using an exact spherically symmetric solution in presence of a cosmological constant. At low red-shift the expansion is more precise than linear perturbation theory prediction. We then use the local expansion to reconstruct the metric from the monopole of the density contrast. We test the inversion method using numerical calculations and find a good agreement within the regime of validity of the red-shift expansion. The method could be applied to observational data to reconstruct the metric of the local Universe with a level of precision higher than the one achievable using perturbation theory.Comment: 18 pages,5 figure

Impact of COVID-19 on cardiovascular testing in the United States versus the rest of the world

Objectives: This study sought to quantify and compare the decline in volumes of cardiovascular procedures between the United States and non-US institutions during the early phase of the coronavirus disease-2019 (COVID-19) pandemic. Background: The COVID-19 pandemic has disrupted the care of many non-COVID-19 illnesses. Reductions in diagnostic cardiovascular testing around the world have led to concerns over the implications of reduced testing for cardiovascular disease (CVD) morbidity and mortality. Methods: Data were submitted to the INCAPS-COVID (International Atomic Energy Agency Non-Invasive Cardiology Protocols Study of COVID-19), a multinational registry comprising 909 institutions in 108 countries (including 155 facilities in 40 U.S. states), assessing the impact of the COVID-19 pandemic on volumes of diagnostic cardiovascular procedures. Data were obtained for April 2020 and compared with volumes of baseline procedures from March 2019. We compared laboratory characteristics, practices, and procedure volumes between U.S. and non-U.S. facilities and between U.S. geographic regions and identified factors associated with volume reduction in the United States. Results: Reductions in the volumes of procedures in the United States were similar to those in non-U.S. facilities (68% vs. 63%, respectively; p = 0.237), although U.S. facilities reported greater reductions in invasive coronary angiography (69% vs. 53%, respectively; p < 0.001). Significantly more U.S. facilities reported increased use of telehealth and patient screening measures than non-U.S. facilities, such as temperature checks, symptom screenings, and COVID-19 testing. Reductions in volumes of procedures differed between U.S. regions, with larger declines observed in the Northeast (76%) and Midwest (74%) than in the South (62%) and West (44%). Prevalence of COVID-19, staff redeployments, outpatient centers, and urban centers were associated with greater reductions in volume in U.S. facilities in a multivariable analysis. Conclusions: We observed marked reductions in U.S. cardiovascular testing in the early phase of the pandemic and significant variability between U.S. regions. The association between reductions of volumes and COVID-19 prevalence in the United States highlighted the need for proactive efforts to maintain access to cardiovascular testing in areas most affected by outbreaks of COVID-19 infection

Difficulties, guidelines and review of developing an acute rejection model after rat intestinal transplantation

Experimental small bowel transplantation (SBT) in rats has been proven to be a useful tool for the study of ischemia-reperfusion and immunological aspects related to solid organ transplantation. However, the model is not completely refined, specialized literature is scarce and complex technical details are typically omitted or confusing. Most studies related to acute rejection (AR) use the orthotopic standard, with small sample sizes due to its high mortality, whereas those studying chronic rejection (CR) use the heterotopic standard, which allows longer term survival but does not exactly reflect the human clinical scenario. Various animal strains have been used, and the type of rejection and the timing of its analysis differ among authors. The double purpose of this study was to develop an improved unusual AR model of SBT using the heterotopic technique, and to elaborate a guide useful to implement experimental models for studying AR. We analyzed the model's technical details and expected difficulties in overcoming the learning curve for such a complex microsurgical model, identifying the potential problem areas and providing a step-by-step protocol and reference guide for future surgeons interested in the topic. We also discuss the historic and more recent options in the literature.Fil: Andres, Ane Miren. Hospital Universitario La Paz; EspañaFil: Santamaria, Monica. Hospital Universitario La Paz; EspañaFil: Hernandez Oliveros, Francisco. Hospital Universitario La Paz; EspañaFil: Guerra, Laura. Hospital Universitario La Paz; EspañaFil: Lopez, Sergio. Hospital Universitario La Paz; EspañaFil: Stringa, Pablo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas; Argentina. Universidad Favaloro. Área de Investigación y Desarrollo; ArgentinaFil: Vallejo, Maria Teresa. Hospital Universitario La Paz; EspañaFil: Largo, Carlota. Hospital Universitario La Paz; EspañaFil: Encinas, Jose Luis. Hospital Universitario La Paz; EspañaFil: Garcia de las Heras, Maria Soledad. Universidad Rey Juan Carlos; EspañaFil: Lopez Santamaria, Manuel. Hospital Universitario La Paz; EspañaFil: Tovar, Juan Antonio. Hospital Universitario La Paz; Españ

II Congreso internacional en educación física, recreación, deporte y actividad física. “Innovación y tendencias” - Memorias

El II Congreso Internacional de Educación Física, Recreación, Deporte y Actividad Física: “Innovación y Tendencias“ y el II Encuentro de Egresados del Departamento de Cultura Física de la Universidad de Córdoba se realizó en la ciudad de Montería, capital del Departamento de Córdoba, Colombia, como iniciativa del Grupo de Investigación en Ciencias de la Actividad Fisica y la Salud –GICAFS- del Departamento de Cultura Física, perteneciente a la Facultad de Educación y Ciencias Humanas de la Universidad de Córdoba, como muestra hacia la comunidad académica y la sociedad en general de la responsabilidad ética, social y profesional, para aportar a la construcción de tejido social, atendiendo a las recomendaciones del plan decenal del deporte, la Educación Física, la Recreación y la Actividad Física 2009-2019 (COLDEPORTES, 2009).Edición 201