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Applicability of Winthrop Score for the Diagnosis of Influenza A in the Emergency Department of Hospital Pablo Arturo Suárez, January to March of 2018
Introduction: In 2010, the Department of Infectious Diseases at Winthrop University Hospital designed a score system for the diagnosis of Legionella pneumonia. In this study, we applied the score to patients with acute respiratory symptoms suspected of having type A influenza. The identification of patients at medium to high risk of Influenza A allows for early initiation of treatment.Objective: To study the applicability of the Winthrop score for the diagnosis of Influenza A.Methodology: A prospective cohort study was performed in 2018 at Hospital Pablo Arturo Suárez, in Quito, Ecuador. Patients 0 to 100 years old presenting to the emergency department with influenza-like illness in January-March of 2018 were included in the study. Winthrop score results were then compared with the result of the reverse transcription polymerase chain reaction (RT-PCR) for influenza A, the gold standard for diagnosis. Sensitivity, specificity, positive and negative predictive values, and likelihood ratios were used to establish the diagnostic performance of this point system for influenza A within the sample at large and in subgroup analyses by age (<5 years, 5-65 years, and >65 years) and comorbidities.Results: 149 patients were enrolled in the study period. The study population included 81 males (54.4%) and the majority of patients were less than 5 years of age (N=85, 57.0%). Furthermore, almost one-third of the patients were less than one year old (N=38, 25.5%). According to the Winthrop point system, 68.5% of the cases had a low probability of having influenza (n = 102), 8.7% of cases had a medium probability (n = 13) and 22.8 % of cases had a high probability (n = 34). The RT-PCR test for influenza was positive for 26.2% of patients (n = 39). The Winthrop point system had a sensitivity of 97.4%, specificity of 91.8%, positive predictive value of 80.8%, negative predictive value of 99.0%, positive likelihood ratio of 11.9, and negative likelihood ratio of 35.8 in the total study population. For children under 5 years, a sensitivity of 100%, specificity of 96.3%, positive predictive value of 77.7%, negative predictive value of 100%, positive likelihood ratio of 27, and negative likelihood ratio of 0. In patients older than 6 years, a sensitivity of 96.9%, specificity of 89%, positive predictive value of 84.21%, negative predictive value of 98%, positive likelihood ratio of 8.8, and negative likelihood ratio of 29.4. Testing in patients over 65 years had a sensitivity of 100%, specificity of 90%, positive predictive value of 87.5%, negative predictive value of 100%, positive likelihood ratio of 10 and negative likelihood ratio of 0. Finally, patients with comorbidities had a sensitivity of 90%, specificity of 88.24%, positive predictive value of 81.82%, negative predictive value of 93.75%, positive likelihood ratio of 7.65, and negative likelihood ratio of 8.82.Conclusions: The Winthrop score performed well in predicting Influenza A in patients with acute respiratory symptoms. This score may be useful in settings were Influenza A PCR testing is unavailable
A recursive-faulting model of distributed damage in confined brittle materials
We develop a model of distributed damage in brittle materials deforming in triaxial compression based on the explicit construction of special microstructures obtained by recursive faulting. The model aims to predict the effective or macroscopic behavior of the material from its elastic and fracture properties; and to predict the microstructures underlying the microscopic behavior. The model accounts for the elasticity of the matrix, fault nucleation and the cohesive and frictional behavior of the faults. We analyze the resulting quasistatic boundary value problem and determine the relaxation of the potential energy, which describes the macroscopic material behavior averaged over all possible fine-scale structures. Finally, we present numerical calculations of the dynamic multi-axial compression experiments on sintered aluminum nitride of Chen and Ravichandran [1994. Dynamic compressive behavior of ceramics under lateral confinement. J. Phys. IV 4, 177–182; 1996a. Static and dynamic compressive behavior of aluminum nitride under moderate confinement. J. Am. Soc. Ceramics 79(3), 579–584; 1996b. An experimental technique for imposing dynamic multiaxial compression with mechanical confinement. Exp. Mech. 36(2), 155–158; 2000. Failure mode transition in ceramics under dynamic multiaxial compression. Int. J. Fracture 101, 141–159]. The model correctly predicts the general trends regarding the observed damage patterns; and the brittle-to-ductile transition resulting under increasing confinement
Educational Attainment and Risk Preference
We explore the relationship between risk preference and educational attainment for a sample of adults drawn from the 1996 U.S. Panel Study of Income Dynamics (PSID). Using a sequence of questions from the 1996 PSID, we construct measures of an individual´s risk aversion and risk tolerance allowing us to explore the implications of interpersonal differences in risk preference for educational attainment. Our empirical findings suggest that an individual´s degree of risk aversion (tolerance) is inversely (positively) associated with their educational attainment. In addition, using the 1997 and 2002 Child Development Supplements of the PSID, we explore the relationship between the risk preference of parents and the academic achievements of their children. Our findings suggest that a parent´s degree of risk aversion (tolerance) is negatively (positively) related to the academic achievements of their children
Educational loans and attitudes towards risk
We explore the relationship between willingness to take financial risk and the probability of taking
out a loan for educational purposes as well as the influence of risk attitudes on the size of the loan using data
drawn from the U.S. Survey of Consumer Finances. The findings suggest a positive relationship between
individuals’ willingness to take financial risk and the probability of taking out a loan for educational purposes.
Similarly, individuals’ willingness to take financial risk appears to be an important determinant of the size of the
educational loan. The findings suggest that non-white individuals and individuals from less wealthy
backgrounds are less likely to finance education through loans which could potentially increase inequalities in
education and income if such individuals are deterred from investing in human capital
A direct primitive variable recovery scheme for hyperbolic conservative equations: the case of relativistic hydrodynamics
In this article we develop a Primitive Variable Recovery Scheme (PVRS) to
solve any system of coupled differential conservative equations. This method
obtains directly the primitive variables applying the chain rule to the time
term of the conservative equations. With this, a traditional finite volume
method for the flux is applied in order avoid violation of both, the entropy
and "Rankine-Hugoniot" jump conditions. The time evolution is then computed
using a forward finite difference scheme. This numerical technique evades the
recovery of the primitive vector by solving an algebraic system of equations as
it is often used and so, it generalises standard techniques to solve these kind
of coupled systems. The article is presented bearing in mind special
relativistic hydrodynamic numerical schemes with an added pedagogical view in
the appendix section in order to easily comprehend the PVRS. We present the
convergence of the method for standard shock-tube problems of special
relativistic hydrodynamics and a graphical visualisation of the errors using
the fluctuations of the numerical values with respect to exact analytic
solutions. The PVRS circumvents the sometimes arduous computation that arises
from standard numerical methods techniques, which obtain the desired primitive
vector solution through an algebraic polynomial of the charges.Comment: 19 pages, 6 figures, 2 tables. Accepted for publication in PLOS ON
Anomalous non-ergodic scaling in adiabatic multicritical quantum quenches
We investigate non-equilibrium dynamical scaling in adiabatic quench
processes across quantum multicritical points. Our analysis shows that the
resulting power-law scaling depends sensitively on the control path, and that
anomalous critical exponents may emerge depending on the universality class. We
argue that the observed anomalous behavior originates in the fact that the
dynamical excitation process takes place asymmetrically with respect to the
static multicritical point, and that non-critical energy modes may play a
dominant role. As a consequence, dynamical scaling requires introducing new
non-static exponents.Comment: 4 pages, 4 figures, minor change in figure
Occurrence and mineral chemistry of high pressure phases, Portrillo basalt, southcentral New Mexico
Inclusions of clinopyroxenite, kaersutiteclinopyroxenite, kaersutite-rich inclusions, wehrlite and olivine-clinopyroxenite together with megacrysts of feldspar, kaersutite and spinel are found loose on the flanks of cinder cones, as inclusions within lava flows and within the cores of volcanic bombs in the Quaternary alkali-olivine basalt of the West Potrillo Mountains, southcentral New Mexico. Based on petrological and geochemical evidence the megacysts are interpreted to be phenocrysts which formed at great depth rather that xenocrysts of larger crystal aggregates. These large crystals are believed to have formed as stable phases at high temperature and pressure and have partially reacted with the basalt to produce subhedral to anhedral crystal boundaries. It can be demonstrated that the mafic and ultramafic crystal aggregates were derived from an alkali-basalt source rock generated in the mantle. The inclusions are believed to represent a cumulus body or bodies injected within the lower crust or upper mantle
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