SciCombinator

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Concept: Integer

253

A positivity advantage is known in emotional word recognition in that positive words are consistently processed faster and with fewer errors compared to emotionally neutral words. A similar advantage is not evident for negative words. Results of divided visual field studies, where stimuli are presented in either the left or right visual field and are initially processed by the contra-lateral brain hemisphere, point to a specificity of the language-dominant left hemisphere. The present study examined this effect by showing that the intake of caffeine further enhanced the recognition performance of positive, but not negative or neutral stimuli compared to a placebo control group. Because this effect was only present in the right visual field/left hemisphere condition, and based on the close link between caffeine intake and dopaminergic transmission, this result points to a dopaminergic explanation of the positivity advantage in emotional word recognition.

Concepts: Psychology, Left-wing politics, Right-wing politics, Integer, Political spectrum, Visual field, French Revolution, Michael Gazzaniga

168

OBJECTIVES: To assess whether the flowcharts and discriminators of the Manchester Triage System (MTS) can be used as indicators of alarming signs of serious febrile illness to predict the risk of hospitalization for febrile children who present at the emergency department (ED). STUDY DESIGN: Observational study, which included 2455 children (<16 years) who came to the ED of a university hospital with fever as their main complaint (May 2007-July 2009). Alarming signs for serious febrile illness were matched with MTS flowcharts and discriminators. At triage, the percentage of alarming signs positive was calculated. The diagnostic ability of the percentage of alarming signs positive to identify children at risk of hospitalization was assessed by calculating positive and negative likelihood ratios. RESULTS: Thirty percent of children had at least 1 alarming sign positive at triage. Twenty-three percent were hospitalized. Positive likelihood ratios of hospitalization were 5.0 (95% CI: 3.9-6.5) for children with >20% of alarming signs positive at triage and 12.0 (95% CI: 5.2-27.6) for those with >40% of alarming signs positive. Negative likelihood ratios were 0.8 (95% CI: 0.8-0.8) and 1.0 (95% CI: 0.9-1.0), respectively. CONCLUSIONS: By alternatively using the flowcharts and discriminators of the MTS as alarming signs, rather than urgency classifiers, the MTS can function as a simple, readily available tool to identify febrile children at risk of hospitalization early in the care process. This knowledge may help to improve ED throughput times as well as admission and discharge management at pediatric EDs.

Concepts: Scientific method, Hospital, Fever, 0, Integer, Triage

89

Background Acute left ventricular dysfunction is a major complication of cardiac surgery and is associated with increased mortality. Meta-analyses of small trials suggest that levosimendan may result in a higher rate of survival among patients undergoing cardiac surgery. Methods We conducted a multicenter, randomized, double-blind, placebo-controlled trial involving patients in whom perioperative hemodynamic support was indicated after cardiac surgery, according to prespecified criteria. Patients were randomly assigned to receive levosimendan (in a continuous infusion at a dose of 0.025 to 0.2 μg per kilogram of body weight per minute) or placebo, for up to 48 hours or until discharge from the intensive care unit (ICU), in addition to standard care. The primary outcome was 30-day mortality. Results The trial was stopped for futility after 506 patients were enrolled. A total of 248 patients were assigned to receive levosimendan and 258 to receive placebo. There was no significant difference in 30-day mortality between the levosimendan group and the placebo group (32 patients [12.9%] and 33 patients [12.8%], respectively; absolute risk difference, 0.1 percentage points; 95% confidence interval [CI], -5.7 to 5.9; P=0.97). There were no significant differences between the levosimendan group and the placebo group in the durations of mechanical ventilation (median, 19 hours and 21 hours, respectively; median difference, -2 hours; 95% CI, -5 to 1; P=0.48), ICU stay (median, 72 hours and 84 hours, respectively; median difference, -12 hours; 95% CI, -21 to 2; P=0.09), and hospital stay (median, 14 days and 14 days, respectively; median difference, 0 days; 95% CI, -1 to 2; P=0.39). There was no significant difference between the levosimendan group and the placebo group in rates of hypotension or cardiac arrhythmias. Conclusions In patients who required perioperative hemodynamic support after cardiac surgery, low-dose levosimendan in addition to standard care did not result in lower 30-day mortality than placebo. (Funded by the Italian Ministry of Health; CHEETAH ClinicalTrials.gov number, NCT00994825 .).

Concepts: Medical statistics, Statistical significance, Cardiac arrest, Addition, Placebo, Normal distribution, The Trial, Integer

37

We examine the temporal evolution of digital communication activity relating to the American anti-capitalist movement Occupy Wall Street. Using a high-volume sample from the microblogging site Twitter, we investigate changes in Occupy participant engagement, interests, and social connectivity over a fifteen month period starting three months prior to the movement’s first protest action. The results of this analysis indicate that, on Twitter, the Occupy movement tended to elicit participation from a set of highly interconnected users with pre-existing interests in domestic politics and foreign social movements. These users, while highly vocal in the months immediately following the birth of the movement, appear to have lost interest in Occupy related communication over the remainder of the study period.

Concepts: Sociology, Natural number, Integer, Remainder, Social movement, Twitter, ASCII, Activism

36

The threat of free-riding makes the marshalling of cooperation from group members a fundamental challenge of social life. Where classical social science theory saw the enforcement of moral boundaries as a critical way by which group members regulate one another’s self-interest and build cooperation, moral judgments have most often been studied as processes internal to individuals. Here we investigate how the interpersonal expression of positive and negative moral judgments encourages cooperation in groups and prosocial behavior between group members. In a laboratory experiment, groups whose members could make moral judgments achieved greater cooperation than groups with no capacity to sanction, levels comparable to those of groups featuring costly material sanctions. In addition, members of moral judgment groups subsequently showed more interpersonal trust, trustworthiness, and generosity than all other groups. These findings extend prior work on peer enforcement, highlighting how the enforcement of moral boundaries offers an efficient solution to cooperation problems and promotes prosocial behavior between group members.

Concepts: Psychology, Sociology, Science, Morality, Integer, Social relation

28

Palladium-catalyzed cyclization of imines has been developed to construct the extremely rare 3H-pyrrolo[2,3-c]quinoline ring system for diversity oriented first total synthesis of antimalarial marine natural product Aplidiopsamine A as well as synthesis of Marinoquinoline A and potential natural product hybrid NCLite-M1.

Concepts: Total synthesis, Paclitaxel total synthesis, Integer, Imine, Natural product, Paclitaxel, Multiplication, Natural products

27

We report the enantiospecific total synthesis of (+)-tubingensin A. Our synthesis features an aryne cyclization to efficiently introduce the vicinal quaternary stereocenters of the natural product and proceeds in only 9 steps (longest linear sequence) from known compounds.

Concepts: Total synthesis, Paclitaxel total synthesis, Natural number, Isomorphism, Integer, Partially ordered set, Ordinal number, Well-order

27

The first enantioselective total syntheses of virosaine A and bubbialidine are described. Key transformations include the formation of a tetracyclic intermediate via an intramolecular aza-Michael addition, generation of a N-hydroxy-pyrrolidine through a Cope elimination and an intramolecular [1,3]-dipolar cycloaddition to generate a complex 7-oxa-1-azabicyclo[3.2.1]octane ring system.

Concepts: Total synthesis, Paclitaxel total synthesis, Chemical synthesis, Vector space, Alkene, Real number, Integer, Elimination reaction

26

Although quinone methides are often postulated as intermediates in the biosynthesis of many polyphenolic natural products, deploying their power in a laboratory setting to achieve similar bond constructions has sometimes proven challenging. Herein, a total synthesis of the resveratrol trimer vaticanol A has been achieved through three instances of quinone methide chemistry. These operations, one of which succeeded only under very specific conditions, expediently generated its [7,5]-carbocyclic core, afforded a unique sequence for dihydrobenzofuran formation, and concurrently generated, in addition to the target molecule, a series of diastereomers reflective of many other isolates.

Concepts: Molecule, Chemistry, Atom, Chemical substance, Total synthesis, Sequence, The Target, Integer

26

Spontaneous breathing has been shown to induce both positive and negative effects on the function and on injury of lungs and diaphragm during critical illness; thus, monitoring of the breathing effort generated by the patient might be valuable for a better understanding of the mechanisms of disease and to set properly ventilation. The purpose of this review is to summarize the recent findings on the different techniques available to measure the patient’s breathing effort, mainly during spontaneous assisted ventilation.

Concepts: Lung, Patient, Thermodynamics, Real number, Integer