Braneworlds, Conformal Fields and the Gravitons

We investigate the dynamics of Randall-Sundrum AdS5 braneworlds with 5-dimensional conformal matter fields. In the scenario with a compact fifth dimension the class of conformal fields with weight -4 is associated with exact 5-dimensional warped geometries which are stable under radion field perturbations and describe on the brane the dynamics of inhomogeneous dust, generalized dark radiation and homogeneous polytropic dark energy. We analyse the graviton mode flutuations around this class of background solutions and determine their mass eigenvalues and wavefunctions from a Sturm-Liouville problem. We show that the localization of gravity is not sharp enough for large mass hierarchies to be generated. We also discuss the physical bounds imposed by experiments in particle physics, in astrophysics and in precise measurements of the low energy gravitational interaction.Comment: LaTeX, 9 pages, 2 figures. Based on talk given in the Second International Conference on Quantum Theories and the Renormalization Group in Gravity and Cosmology, CSIC and University of Barcelona, Barcelona, Spain, 11-15 July 2006. Submitted to be published in the Conference Proceedings, J. Phys. A: Math. Ge

Probing features of the Lee-Wick quantum electrodynamics

In this paper we discuss some aspects concerning the electromagnetic sector of the abelian Lee-Wick (LW) quantum electrodynamics (QED). Using the Dirac's theory of constrained systems, the higher-order canonical quantization of the LW electromagnetism is performed. A quantum bound on the LW heavy mass is also estimated using the best known measurement of the anomalous magnetic moment of the electron. Finally it is shown that magnetic monopoles can coexist peacefully in the LW scenario.Comment: Replaced with published versio

Consensus must be found on intravenous fluid therapy management in trauma patients

Introduction: Trauma is an important cause of death among young people and 30-40% of this mortality rate is due to hypovolemic shock, intensified by trauma's lethal triad: Hypothermia, Acidosis, and Coagulopathy. Nurses are responsible for managing fluid therapy administration in trauma victims. The purpose of this study is to analyse the reasons why intravenous fluid therapy is recommended for trauma patients' hemodynamic stabilization. Methods: This narrative literature review included published and unpublished studies in English, Spanish or Portuguese between 1994 and January 2019. The search results were analyzed by two independent reviewers. Inclusion criteria encompasses quantitative studies involving trauma victims aged over 18 who underwent fluid therapy in a prehospital assessment context. Results&Discussion: 11 quantitative studies were included. 9 involved the use of fluid therapy for hypotension treatment and 2 of the studies analyzed involved the use of warmed fluid therapy for hypothermia treatment. The analysis performed reveals that the administration of aggressive fluid therapy seems to be responsible for the worsening of the lethal triad. In the presence of traumatic brain injury, permissive hypotension is not allowed due to the negative impact on cerebral perfusion pressure. Used as warming measure, warmed fluid therapy does not seem to have a significant impact on body temperature. Conclusions: There is no consensus regarding the administration of fluid therapy to trauma patients. This conclusion clearly supports the need to develop more randomized controlled trials in order to understand the effectiveness of such measure when it comes to control hypovolemia and hypothermia.info:eu-repo/semantics/publishedVersio

OS diversity for intrusion tolerance: Myth or reality?

One of the key benefits of using intrusion-tolerant systems is the possibility of ensuring correct behavior in the presence of attacks and intrusions. These security gains are directly dependent on the components exhibiting failure diversity. To what extent failure diversity is observed in practical deployment depends on how diverse are the components that constitute the system. In this paper we present a study with operating systems (OS) vulnerability data from the NIST National Vulnerability Database. We have analyzed the vulnerabilities of 11 different OSes over a period of roughly 15 years, to check how many of these vulnerabilities occur in more than one OS. We found this number to be low for several combinations of OSes. Hence, our analysis provides a strong indication that building a system with diverse OSes may be a useful technique to improve its intrusion tolerance capabilities

BP Reduction, Kidney Function Decline, and Cardiovascular Events in Patients without CKD.

BACKGROUND AND OBJECTIVES: In the Systolic Blood Pressure Intervention Trial (SPRINT), intensive systolic BP treatment (target <120 mm Hg) was associated with fewer cardiovascular events and higher incidence of kidney function decline compared with standard treatment (target <140 mm Hg). We evaluated the association between mean arterial pressure reduction, kidney function decline, and cardiovascular events in patients without CKD. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: We categorized patients in the intensive treatment group of the SPRINT according to mean arterial pressure reduction throughout follow-up: <20, 20 to <40, and ≥40 mm Hg. We defined the primary outcome as kidney function decline (≥30% reduction in eGFR to <60 ml/min per 1.73 m2 on two consecutive determinations at 3-month intervals), and we defined the secondary outcome as cardiovascular events. In a propensity score analysis, patients in each mean arterial pressure reduction category from the intensive treatment group were matched with patients from the standard treatment group to calculate the number needed to treat regarding cardiovascular events and the number needed to harm regarding kidney function decline. RESULTS: In the intensive treatment group, 1138 (34%) patients attained mean arterial pressure reduction <20 mm Hg, 1857 (56%) attained 20 to <40 mm Hg, and 309 (9%) attained ≥40 mm Hg. Adjusted hazard ratios for kidney function decline were 2.10 (95% confidence interval, 1.22 to 3.59) for mean arterial pressure reduction between 20 and 40 mm Hg and 6.22 (95% confidence interval, 2.75 to 14.08) for mean arterial pressure reduction ≥40 mm Hg. In propensity score analysis, mean arterial pressure reduction <20 mm Hg presented a number needed to treat of 44 and a number needed to harm of 65, reduction between 20 and <40 mm Hg presented a number needed to treat of 42 and a number needed to harm of 35, and reduction ≥40 mm Hg presented a number needed to treat of 95 and a number needed to harm of 16. CONCLUSIONS: In the intensive treatment group of SPRINT, larger declines in mean arterial pressure were associated with higher incidence of kidney function decline. Intensive treatment seemed to be less favorable when a larger reduction in mean arterial pressure was needed to attain the BP target.info:eu-repo/semantics/publishedVersio

Ritmicidade de crescimento e ramificações provocadas pelos diferentes tipos de traumatismo nas plantas jovens de erva-mate (Ilex paraguariensis St.Hil.).

.Organizado por Patricia Póvoa de Mattos, Celso Garcia Auer, Rejane Stumpf Sberze, Katia Regina Pichelli e Paulo César Botosso

Maxwell-Chern-Simons vortices in a CPT-odd Lorentz-violating Higgs Electrodynamics

We have studied BPS vortices in a CPT-odd and Lorentz-violating Maxwell-Chern-Simons-Higgs (MCSH) electrodynamics attained from the dimensional reduction of the Carroll-Field-Jackiw-Higgs model. The Lorentz-violating parameter induces a pronounced behavior at origin (for the magnetic/electric fields and energy density) which is absent in the MCSH vortices. For some combination of the Lorentz-violating coefficients there always exist a sufficiently large winding number $n_{0}$ such that for all $$ the magnetic field flips its signal, yielding two well defined regions with opposite magnetic flux. However, the total magnetic flux remains quantized and proportional to the winding number.Comment: Revtex style, 8 page