8 research outputs found
Cosmological Measurements with General Relativistic Galaxy Correlations
We investigate the cosmological dependence and the constraining power of
large-scale galaxy correlations, including all redshift-distortions,
wide-angle, lensing and gravitational potential effects on linear scales. We
analyze the cosmological information present in the lensing convergence and in
the gravitational potential terms describing the so-called "relativistic
effects," and we find that, while smaller than the information contained in
intrinsic galaxy clustering, it is not negligible. We investigate how
neglecting them does bias cosmological measurements performed by future
spectroscopic and photometric large-scale surveys such as SKA and Euclid. We
perform a Fisher analysis using the CLASS code, modified to include
scale-dependent galaxy bias and redshift-dependent magnification and evolution
bias. Our results show that neglecting relativistic terms introduces an error
in the forecasted precision in measuring cosmological parameters of the order
of a few tens of percent, in particular when measuring the matter content of
the Universe and primordial non-Gaussianity parameters. Therefore, we argue
that radial correlations and integrated relativistic terms need to be taken
into account when forecasting the constraining power of future large-scale
number counts of galaxy surveys.Comment: 18 pages, 10 figure
Management and Clinical Aspects of Burned Patients Affected by SARS-COV2
At the end of January 2020, SARS-CoV-2 started escalating worldwide. COVID-19 can exert its effects on immunity, inflammation, and multi-organ system disease, common denominators with the burn injury. The pandemic required major efforts to Burn centres in order to preserve burn patients’ care and contribute to the health care response. In our Burn Unit we autonomously developed a protocol for patients acceptance and surveillance of the hospitalized ones and the personnel. We briefly describe our experience with six cases of burn patients infected by SARS-CoV-2 highlighting the overlap between medical treatment of burn patients and COVID-19 patients. To avoid viral spreading epidemiologic control is essential, especially preventive measures such as isolation of infected patients and identification of the source of infection. In our surgical practice, we increased the use of enzymatic debridement avoiding procedures with a high risk of viral particles spreading. Personnel protection and dedicated pathways have been planned, optimizing air circulation and disinfection. Vaccines represent the best hope for the global population to stop the viral spread, despite new variants outbreaks
Nutritional Support for Bariatric Surgery Patients: The Skin beyond the Fat
Body contouring surgery after the massive weight loss due to bariatric surgery deals with different kinds of complications. The aim of this review is to analyze the role that some nutrients may play in tissue healing after surgery, thus helping plastic surgeons to improve the aesthetic and health outcomes in massive weight loss patients under a multidisciplinary approach. As a matter of fact, preoperative nutritional deficiencies have been shown for vitamins and minerals in a large percentage of post-bariatric patients. Preoperative deficiencies mainly concern iron, zinc, selenium, and vitamins (both fat-soluble and water-soluble), but also total protein. During the postoperative period, these problems may increase because of the patients’ very low intake of vitamins and minerals after bariatric surgery (below 50% of the recommended dietary allowance) and the patients’ low compliance with the suggested multivitamin supplementation (approximately 60%). In the postoperative period, more attention should be given to nutritional aspects in regard to the length of absorptive area and the percentage of weight loss
Curvature constraints from Large Scale Structure
We modified the CLASS code in order to include relativistic galaxy number counts in spatially curved geometries; we present the formalism and study the effect of relativistic corrections on spatial curvature. The new version of the code is now publicly available. Using a Fisher matrix analysis, we investigate how measurements of the spatial curvature parameter \u3a9K with future galaxy surveys are affected by relativistic effects, which influence observations of the large scale galaxy distribution. These effects include contributions from cosmic magnification, Doppler terms and terms involving the gravitational potential. As an application, we consider angle and redshift dependent power spectra, which are especially well suited for model independent cosmological constraints. We compute our results for a representative deep, wide and spectroscopic survey, and our results show the impact of relativistic corrections on spatial curvature parameter estimation. We show that constraints on the curvature parameter may be strongly biased if, in particular, cosmic magnification is not included in the analysis. Other relativistic effects turn out to be subdominant in the studied configuration. We analyze how the shift in the estimated best-fit value for the curvature and other cosmological parameters depends on the magnification bias parameter, and find that significant biases are to be expected if this term is not properly considered in the analysis