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Penicillin Use and Duration of Bacteremia, Length of Stay, and 30-day Readmission in Hospitalized Patients with Penicillin-Susceptible Staphylococcus aureus
Staphylococcus aureus is the most common bacterial pathogen in hospitalized patients, and is a leading cause of bacteremia. Current guidelines recommend when the etiology of infection is known or suspected, the antimicrobial most cost-effective, least toxic, and most narrow in spectrum be used. To evaluate treatment of PSSA bacteremia with penicillin versus other antibiotics, a retrospective cohort study was conducted at a tertiary care center in Western Massachusetts using data collected from 2003 to 2013. One-hundred and eight patients with PSSA bacteremia were included. The primary exposure was defined as treatment with penicillin within 3 days of the first positive culture. The primary outcome was duration of bacteremia, with length of hospital stay and 30-day readmission as secondary outcomes. Data were abstracted from administrative databases and medical records, and multivariable and propensity-score-adjusted analyses were conducted. Overall, there was no difference in duration of bacteremia according to treatment (p=0.77), and a non-significant 25% increase in length of stay post-culture was observed in patients not receiving penicillin (p=0.34). Propensity-score-adjusted analyses also did not yield significant differences in clinical outcomes. The results of this study suggest no significant associations between treatment with penicillin versus other antibiotics and clinical outcomes. Given the low cost and decreased risk of developing multidrug-resistant bacteria, PSSA bacteremia should be treated preferentially with penicillin. However, given the small sample size, and the potentially wide range of antibiotics used in place of penicillin, caution should be exercised in interpreting these results. Larger multi-site studies are needed to address these associations
Localized Acceleration of Energetic Particles by a Weak Shock in the Solar Corona
Globally-propagating shocks in the solar corona have long been studied to quantify their involvement in the acceleration of energetic particles. However, this work has tended to focus on large events associated with strong solar flares and fast coronal mass ejections (CMEs), where the waves are sufficiently fast to easily accelerate particles to high energies. Here we present observations of particle acceleration associated with a global wave event which occurred on 1 October 2011. Using differential emission measure analysis, the global shock wave was found to be incredibly weak, with an Alfv\'en Mach number of ~1.008-1.013. Despite this, spatially-resolved type III radio emission was observed by the Nan\c{c}ay RadioHeliograph at distinct locations near the shock front, suggesting localised acceleration of energetic electrons. Further investigation using a magnetic field extrapolation identified a fan structure beneath a magnetic null located above the source active region, with the erupting CME contained within this topological feature. We propose that a reconfiguration of the coronal magnetic field driven by the erupting CME enabled the weak shock to accelerate particles along field lines initially contained within the fan and subsequently opened into the heliosphere, producing the observed type III emission. These results suggest that even weak global shocks in the solar corona can accelerate energetic particles via reconfiguration of the surrounding magnetic field
Is Canada really an education superpower? The impact of non-participation on results from PISA 2015
The purpose of large-scale international assessments is to compare educational achievement across countries. For such cross-national comparisons to be meaningful, the participating students must be representative of the target population. In this paper, we consider whether this is the case for Canada, a country widely recognised as high performing in the Programme for International Student Assessment (PISA). Our analysis illustrates how the PISA 2015 sample for Canada only covers around half of the 15-year-old population, compared to over 90% in countries like Finland, Estonia, Japan and South Korea. We discuss how this emerges from differences in how children with special educational needs are defined and rules for their inclusion in the study, variation in school participation rates and the comparatively high rates of pupils’ absence in Canada during the PISA study. The paper concludes by investigating how Canada’s PISA 2015 rank would change under different assumptions about how the non-participating students would have performed were they to have taken the PISA test
Diagnosis of pathological conditions through electronic nose analysis of urine samples: a systematic review and meta-analysis
Currently available urinalysis methods are often applied for screening and monitoring of several pathologies. However, traditionally analyzed biomarkers in urinalysis still lack sensitivity and specificity to accurately diagnose some diseases. Several studies have proposed the use of electronic noses (eNoses) for the analysis of volatile organic compounds in urine samples that may, directly or indirectly, correlate with certain pathologies. Hence, the aim of this study was to perform a systematic review and meta-analysis of studies concerning the use of portable electronic noses for diagnosis or monitoring of pathologies through analysis of urine samples. A systematic review of the literature was held according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Twenty-four articles met the inclusion criteria and were included in the analysis. The results of the revised studies showed that there are various volatile organic compound profiles, identified through eNose analysis, that may be applied for diagnosis or monitoring of several diseases, such as diabetes, urinary tract infection, inflammatory bowel disease, and kidney disease. A meta-analysis was conducted taking into consideration the data of 10 of the initial 24 articles. The pooled sensitivity, specificity, and diagnostic odds ratio were 84% (95% CI, 0.72–0.92), 85% (95% CI, 0.75–0.91), and 24.17 (95% CI: 7.85–74.41), respectively. The area under the receiver operating characteristic curve was 0.897. These results suggest that eNose technology has adequate diagnostic accuracy for several pathologies and could be a promising screening tool for clinical settings. However, more studies are needed to reduce heterogeneity between results.João Cavaleiro Rufo was funded by Fundação para a Ciência e Tecnologia through the Stimulus for Scientific Employment Individual Support (2020.01350.CEECIND). Mariana Farraia was funded by Fundação para a Ciência e Tecnologia through the PhD Grant Number SFRH/BD/145168/2019. This study was funded by FEDER through the Operational Program Competitiveness and Internationalization and national funding from the Foundation for Science and Technology—FCT (Portuguese Ministry of Science, Technology, and Higher Education) under the Unidade de Investigação em Epidemiologia—Instituto de Saúde Pública da Universidade do Porto (EPIUnit) (POCI-01-0145-FEDER-006862; Ref. UID/DTP/04750/2019)
A study of the Relationship Between the Microwave and Meter-Wavelength Emissions from the Solar Flare on June 3, 2021
We present the preliminary results of the flare analysis. The event took place on 3rd June 2021, at 01:36 UT. It was observed in microwaves by Siberian Radioheliograph (SRH) within the 3-6 GHz, Broadband Microwave Spectropolarimeter (BBMS) and in meter radio range by e-Callisto spectrograph network. We found several of the type III bursts and the type-J burst in the meter radio range. At the same time, only the one burst was detected in the averaged time profiles of microwaves emission. This one corresponds to the strongest type III radio burst. Using the images by SRH, we defined the two sources and analysis of the time profiles of them separately. This approach allowed us finding the microwave bursts associated with the radio bursts, which were not distinguished in averaged time profiles. The delays between microwave and meter radio emission obtained from observations were compared with the results of preliminary analysis of dynamic spectra in radio meter range
Assessment of the risk and characterization of non-melanoma skin cancer in Kindler syndrome: study of a series of 91 patients.
BACKGROUND: Kindler Syndrome (KS) is a rare genodermatosis characterized by skin fragility, skin atrophy, premature aging and poikiloderma. It is caused by mutations in the FERMT1 gene, which encodes kindlin-1, a protein involved in integrin signalling and the formation of focal adhesions. Several reports have shown the presence of non-melanoma skin cancers in KS patients but a systematic study evaluating the risk of these tumors at different ages and their potential outcome has not yet been published. We have here addressed this condition in a retrospective study of 91 adult KS patients, characterizing frequency, metastatic potential and body distribution of squamous cell carcinoma (SCC) in these patients. SCC developed in 13 of the 91 patients.
RESULTS: The youngest case arose in a 29-year-old patient; however, the cumulative risk of SCC increased to 66.7% in patients over 60 years of age. The highly aggressive nature of SCCs in KS was confirmed showing that 53.8% of the patients bearing SCCs develop metastatic disease. Our data also showed there are no specific mutations that correlate directly with the development of SCC; however, the mutational distribution along the gene appears to be different in patients bearing SCC from SCC-free patients. The body distribution of the tumor appearance was also unique and different from other bullous diseases, being concentrated in the hands and around the oral cavity, which are areas of high inflammation in this disease.
CONCLUSIONS: This study characterizes SCCs in the largest series of KS patients reported so far, showing the high frequency and aggressiveness of these tumors. It also describes their particular body distribution and their relationship with mutations in the FERMT-1 gene. These data reinforce the need for close monitoring of premalignant or malignant lesions in KS patients
Freak observers and the measure of the multiverse
I suggest that the factor in the pocket-based measure of the
multiverse, , should be interpreted as accounting for equilibrium
de Sitter vacuum fluctuations, while the selection factor accounts for
the number of observers that were formed due to non-equilibrium processes
resulting from such fluctuations. I show that this formulation does not suffer
from the problem of freak observers (also known as Boltzmann brains).Comment: 6 pages, no figures; references adde
Noncommutative Inspired Black Holes in Extra Dimensions
In a recent string theory motivated paper, Nicolini, Smailagic and Spallucci
(NSS) presented an interesting model for a noncommutative inspired,
Schwarzschild-like black hole solution in 4-dimensions. The essential effect of
having noncommutative co-ordinates in this approach is to smear out matter
distributions on a scale associated with the turn-on of noncommutativity which
was taken to be near the 4-d Planck mass. In particular, NSS took this smearing
to be essentially Gaussian. This energy scale is sufficiently large that in 4-d
such effects may remain invisible indefinitely. Extra dimensional models which
attempt to address the gauge hierarchy problem, however, allow for the
possibility that the effective fundamental scale may not be far from 1
TeV, an energy regime that will soon be probed by experiments at both the LHC
and ILC. In this paper we generalize the NSS model to the case where flat,
toroidally compactified extra dimensions are accessible at the Terascale and
examine the resulting modifications in black hole properties due to the
existence of noncommutativity. We show that while many of the
noncommutativity-induced black hole features found in 4-d by NSS persist, in
some cases there can be significant modifications due the presence of extra
dimensions. We also demonstrate that the essential features of this approach
are not particularly sensitive to the Gaussian nature of the smearing employed
by NSS.Comment: 30 pages, 12 figures; slight text modifications and references adde
Thermal hadron production in high energy collisions
It is shown that hadron abundances in high energy e+e-, pp and p{\bar p}
collisions, calculated by assuming that particles originate in hadron gas
fireballs at thermal and partial chemical equilibrium, are in very good
agreement with the data. The freeze-out temperature of the hadron gas fireballs
turns out to be nearly constant over a large center of mass energy range and
not dependent on the initial colliding system. The only deviation from chemical
equilibrium resides in the incomplete strangeness phase space saturation.
Preliminary results of an analysis of hadron abundances in S+S and S+Ag heavy
ion collisions are presented.Comment: 10 pages, 1 .eps figure, talk given at the Strangeness and Quark
Matter 97 conferenc
Age group, location or pedagogue: factors affecting parental choice of kindergartens in Hungary
Hungary has experienced significant political, economic, demographic and social changes since the end of Soviet domination in the 1990s. The gradual move towards liberal-democracy has been accompanied by growing emphasis on individualism, choice and diversity. Universal kindergarten provision for 5-6 year olds is a long established feature of the Hungarian education system, but little is known about parental choice (Török, 2004). A case study (Yin, 2004) of factors influencing parental choice and satisfaction was undertaken in one Hungarian town. This was based on a survey of 251 parents of children attending both mixed-age and same-age groups across 12 kindergartens. Parents suggested that the most important influences were geographical location and the individual pedagogue(s). Given that traditionally each pedagogue follows ‘their’ cohort from kindergarten entry to primary school, their influence appears heightened. Although generally satisfied with their chosen arrangement, parents from same-age groups expressed significantly more confidence and satisfaction, particularly in relation to cognitive development and preparation for school. Parents appear less convinced about the trend towards mixed-age groups and questions are raised about sufficiency of evidence of their benefits in a Hungarian context and the driving factors behind change
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