Effectiveness of a clinical pathway for acute stroke care in a district general hospital: an audit

BACKGROUND: Organised stroke care saves lives and reduces disability. A clinical pathway might be a form of organised stroke care, but the evidence for the effectiveness of this model of care is limited. METHODS: This study was a retrospective audit study of consecutive stroke admissions in the setting of an acute general medical unit in a district general hospital. The case-notes of patients admitted with stroke for a 6-month period before and after introduction of the pathway, were reviewed to determine data on length of stay, outcome, functional status, (Barthel Index, BI and Modified Rankin Scale, MRS), Oxfordshire Community Stroke Project (OCSP) sub-type, use of investigations, specific management issues and secondary prevention strategies. Logistic regression was used to adjust for differences in case-mix. RESULTS: N = 77 (prior to the pathway) and 76 (following the pathway). The median (interquartile range, IQR) age was 78 years (67.75–84.25), 88% were European NZ and 37% were male. The median (IQR) BI at admission for the pre-pathway group was less than the post-pathway group: 6 (0–13.5) vs. 10 (4–15.5), p = 0.018 but other baseline variables were statistically similar. There were no significant differences between any of the outcome or process of care variables, except that echocardiograms were done less frequently after the pathway was introduced. A good outcome (MRS<4) was obtained in 66.2% prior to the pathway and 67.1% after the pathway. In-hospital mortality was 20.8% and 23.1%. However, using logistic regression to adjust for the differences in admission BI, it appeared that admission after the pathway was introduced had a significant negative effect on the probability of good outcome (OR 0.29, 95%CI 0.09-0.99). CONCLUSION: A clinical pathway for acute stroke management appeared to have no benefit for the outcome or processes of care and may even have been associated with worse outcomes. These data support the conclusions of a recent Cochrane review

Design of Experiments for Screening

The aim of this paper is to review methods of designing screening experiments, ranging from designs originally developed for physical experiments to those especially tailored to experiments on numerical models. The strengths and weaknesses of the various designs for screening variables in numerical models are discussed. First, classes of factorial designs for experiments to estimate main effects and interactions through a linear statistical model are described, specifically regular and nonregular fractional factorial designs, supersaturated designs and systematic fractional replicate designs. Generic issues of aliasing, bias and cancellation of factorial effects are discussed. Second, group screening experiments are considered including factorial group screening and sequential bifurcation. Third, random sampling plans are discussed including Latin hypercube sampling and sampling plans to estimate elementary effects. Fourth, a variety of modelling methods commonly employed with screening designs are briefly described. Finally, a novel study demonstrates six screening methods on two frequently-used exemplars, and their performances are compared

An Evolutionary Upgrade of Cognitive Load Theory: Using the Human Motor System and Collaboration to Support the Learning of Complex Cognitive Tasks

Cognitive load theory is intended to provide instructional strategies derived from experimental, cognitive load effects. Each effect is based on our knowledge of human cognitive architecture, primarily the limited capacity and duration of a human working memory. These limitations are ameliorated by changes in long-term memory associated with learning. Initially, cognitive load theory's view of human cognitive architecture was assumed to apply to all categories of information. Based on Geary's (Educational Psychologist 43, 179-195 2008; 2011) evolutionary account of educational psychology, this interpretation of human cognitive architecture requires amendment. Working memory limitations may be critical only when acquiring novel information based on culturally important knowledge that we have not specifically evolved to acquire. Cultural knowledge is known as biologically secondary information. Working memory limitations may have reduced significance when acquiring novel

Evidence for the Contribution of the Hemozoin Synthesis Pathway of the Murine Plasmodium yoelii to the Resistance to Artemisinin-Related Drugs

Plasmodium falciparum malaria is a major global health problem, causing approximately 780,000 deaths each year. In response to the spreading of P. falciparum drug resistance, WHO recommended in 2001 to use artemisinin derivatives in combination with a partner drug (called ACT) as first-line treatment for uncomplicated falciparum malaria, and most malaria-endemic countries have since changed their treatment policies accordingly. Currently, ACT are often the last treatments that can effectively and rapidly cure P. falciparum infections permitting to significantly decrease the mortality and the morbidity due to malaria. However, alarming signs of emerging resistance to artemisinin derivatives along the Thai-Cambodian border are of major concern. Through long-term in vivo pressures, we have been able to select a murine malaria model resistant to artemisinins. We demonstrated that the resistance of Plasmodium to artemisinin-based compounds depends on alterations of heme metabolism and on a loss of hemozoin formation linked to the down-expression of the recently identified Heme Detoxification Protein (HDP). These artemisinins resistant strains could be able to detoxify the free heme by an alternative catabolism pathway involving glutathione (GSH)-mediation. Finally, we confirmed that artemisinins act also like quinolines against Plasmodium via hemozoin production inhibition. The work proposed here described the mechanism of action of this class of molecules and the resistance to artemisinins of this model. These results should help both to reinforce the artemisinins activity and avoid emergence and spread of endoperoxides resistance by focusing in adequate drug partners design. Such considerations appear crucial in the current context of early artemisinin resistance in Asia

A systematic review of tests of empathy in medicine

Abstract Background Empathy is frequently cited as an important attribute in physicians and some groups have expressed a desire to measure empathy either at selection for medical school or during medical (or postgraduate) training. In order to do this, a reliable and valid test of empathy is required. The purpose of this systematic review is to determine the reliability and validity of existing tests for the assessment of medical empathy. Methods A systematic review of research papers relating to the reliability and validity of tests of empathy in medical students and doctors. Journal databases (Medline, EMBASE, and PsycINFO) were searched for English-language articles relating to the assessment of empathy and related constructs in applicants to medical school, medical students, and doctors. Results From 1147 citations, we identified 50 relevant papers describing 36 different instruments of empathy measurement. As some papers assessed more than one instrument, there were 59 instrument assessments. 20 of these involved only medical students, 30 involved only practising clinicians, and three involved only medical school applicants. Four assessments involved both medical students and practising clinicians, and two studies involved both medical school applicants and students. Eight instruments demonstrated evidence of reliability, internal consistency, and validity. Of these, six were self-rated measures, one was a patient-rated measure, and one was an observer-rated measure. Conclusion A number of empathy measures available have been psychometrically assessed for research use among medical students and practising medical doctors. No empathy measures were found with sufficient evidence of predictive validity for use as selection measures for medical school. However, measures with a sufficient evidential base to support their use as tools for investigating the role of empathy in medical training and clinical care are available.</p

Observing Exoplanets with the James Webb Space Telescope

The census of exoplanets has revealed an enormous variety of planets or- biting stars of all ages and spectral types: planets in orbits of less than a day to frigid worlds in orbits over 100 AU; planets with masses 10 times that of Jupiter to planets with masses less than that of Earth; searingly hot planets to temperate planets in the Habitable Zone. The challenge of the coming decade is to move from demography to physical characterization. The James Webb Space Telescope (JWST) is poised to open a revolutionary new phase in our understanding of exoplanets with transit spectroscopy of relatively short period planets and coronagraphic imaging of ones with wide separations from their host stars. This article discusses the wide variety of exoplanet opportunities enabled by JWSTs sensitivity and stability, its high angular resolution, and its suite of powerful instruments. These capabilities will advance our understanding of planet formation, brown dwarfs, and the atmospheres of young to mature planets

Atmospheric retrieval of exoplanets

Exoplanetary atmospheric retrieval refers to the inference of atmospheric properties of an exoplanet given an observed spectrum. The atmospheric properties include the chemical compositions, temperature profiles, clouds/hazes, and energy circulation. These properties, in turn, can provide key insights into the atmospheric physicochemical processes of exoplanets as well as their formation mechanisms. Major advancements in atmospheric retrieval have been made in the last decade, thanks to a combination of state-of-the-art spectroscopic observations and advanced atmospheric modeling and statistical inference methods. These developments have already resulted in key constraints on the atmospheric H2O abundances, temperature profiles, and other properties for several exoplanets. Upcoming facilities such as the JWST will further advance this area. The present chapter is a pedagogical review of this exciting frontier of exoplanetary science. The principles of atmospheric retrievals of exoplanets are discussed in detail, including parametric models and statistical inference methods, along with a review of key results in the field. Some of the main challenges in retrievals with current observations are discussed along with new directions and the future landscape

Combined measurement of differential and total cross sections in the H → γγ and the H → ZZ* → 4ℓ decay channels at s=13 TeV with the ATLAS detector

A combined measurement of differential and inclusive total cross sections of Higgs boson production is performed using 36.1 fb−1 of 13 TeV proton–proton collision data produced by the LHC and recorded by the ATLAS detector in 2015 and 2016. Cross sections are obtained from measured H→γγ and H→ZZ*(→4ℓ event yields, which are combined taking into account detector efficiencies, resolution, acceptances and branching fractions. The total Higgs boson production cross section is measured to be 57.0−5.9 +6.0 (stat.) −3.3 +4.0 (syst.) pb, in agreement with the Standard Model prediction. Differential cross-section measurements are presented for the Higgs boson transverse momentum distribution, Higgs boson rapidity, number of jets produced together with the Higgs boson, and the transverse momentum of the leading jet. The results from the two decay channels are found to be compatible, and their combination agrees with the Standard Model predictions

Search for High-Mass Resonances Decaying to τν in pp Collisions at √s=13 TeV with the ATLAS Detector

A search for high-mass resonances decaying to τν using proton-proton collisions at √s=13 TeV produced by the Large Hadron Collider is presented. Only τ-lepton decays with hadrons in the final state are considered. The data were recorded with the ATLAS detector and correspond to an integrated luminosity of 36.1 fb−1. No statistically significant excess above the standard model expectation is observed; model-independent upper limits are set on the visible τν production cross section. Heavy W′ bosons with masses less than 3.7 TeV in the sequential standard model and masses less than 2.2–3.8 TeV depending on the coupling in the nonuniversal G(221) model are excluded at the 95% credibility level