SciCombinator

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Concept: 0

170

Optical telecommunication employs light pulses travelling down optical fibres; in a binary format logical Ones and Zeroes are represented by the presence or absence of a light pulse in a given time slot, respectively. The fibre’s data-carrying capacity must keep up with increasing demand, but for binary coding it now approaches its limit. Alternative coding schemes beyond binary are currently hotly debated; the challenge is to mitigate detrimental effects from the fibre’s nonlinearity. Here we provide proof-of-principle that coding with solitons and soliton molecules allows to encode two bits of data per clock period. Solitons do not suffer from nonlinearity, rather, they rely on it; this endows them with greater robustness. However, they are universally considered to be restricted to binary coding. With that notion now refuted, it is warranted to rethink future systems.

Concepts: Time, Refractive index, Optical fiber, Binary numeral system, Dispersion, Vector soliton, Polarization, 0

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

149

Recent studies have highlighted the potential role of basic numerical processing in the acquisition of numerical and mathematical competences. However, it is debated whether high-level numerical skills and mathematics depends specifically on basic numerical representations. In this study mathematicians and nonmathematicians performed a basic number line task, which required mapping positive and negative numbers on a physical horizontal line, and has been shown to correlate with more advanced numerical abilities and mathematical achievement. We found that mathematicians were more accurate compared with nonmathematicians when mapping positive, but not negative numbers, which are considered numerical primitives and cultural artifacts, respectively. Moreover, performance on positive number mapping could predict whether one is a mathematician or not, and was mediated by more advanced mathematical skills. This finding might suggest a link between basic and advanced mathematical skills. However, when we included visuospatial skills, as measured by block design subtest, the mediation analysis revealed that the relation between the performance in the number line task and the group membership was explained by non-numerical visuospatial skills. These results demonstrate that relation between basic, even specific, numerical skills and advanced mathematical achievement can be artifactual and explained by visuospatial processing. (PsycINFO Database Record

Concepts: Mathematics, Number, Real number, Set theory, 0, Inequality, Numbers, Subtraction

35

A number of studies have shown a range of negative psychological symptoms (e.g. depression) after exposure to natural disasters. The aim of this study was to determine risk factors for depression in both children and adults who have survived natural disasters.

Concepts: Greek loanwords, Cultural studies, 0, Photography

31

The prognosis in lung cancer depends largely on early stage detection, and thus new screening methods are attracting increasing attention. Canine scent detection has shown promising results in lung cancer detection, but there has only been one previous study that reproduces a screening-like situation. Here breath samples were collected from 122 patients at risk for lung cancer (smokers and ex-smokers); 29 of the subjects had confirmed diagnosis of lung cancer but had not yet been treated and 93 subjects had no signs or symptoms of lung cancer at the time of inclusion. The breath samples were presented to a trained sniffer dog squadron in a double-blind manner. A rigid scientific protocol was used with respect to earlier canine scent detection studies, with one difference: instead of offering one in five positive samples to the dogs, we offered a random number of positive samples (zero to five). The final positive and negative predictive values of 30.9% and 84.0%, respectively, were rather low compared to other studies. The results differed from those of previous studies, indicating that canine scent detection might not be as powerful as is looked for in real screening situations. One main reason for the rather poor performance in our setting might be the higher stress from the lack of positive responses for dogs and handlers.

Concepts: Cancer, Metastasis, Lung cancer, Cancer staging, Addition, Prognosis, 0, Medical test

28

The purpose of this study was to assess the scientific and etiological status of dissociative identity disorder (DID) by examining cases published from 2000 to 2010. In terms of scientific status, DID is a small but ongoing field of study. The review yielded 21 case studies and 80 empirical studies, presenting data on 1171 new cases of DID. A mean of 9 articles, each containing a mean of 17 new cases of DID, emerged each year. In terms of etiological status, many of the central criticisms of the disorder’s validity remain unaddressed. Most cases of DID emerged from a small number of countries and clinicians. In addition, documented cases occurring outside treatment were almost nonexistent. Finally, people simulating DID in the laboratory were mostly indistinguishable from individuals with DID. Overall, DID is still a topic of study, but the research lacks the productivity and focus needed to resolve ongoing controversies surrounding the disorder.

Concepts: Scientific method, Research, Empirical, Mental disorder, 0, Dissociation, Dissociative identity disorder, Dissociative identity disorder in popular culture

27

In order to assess the bioequivalence of 2 different formulations of montelukast, a pivotal trial for the montelukast 10 mg film-coated tablets formulation and a pivotal trial for the montelukast 5 mg chewable tablets formulation were conducted.For the 10 mg study, 34 healthy subjects were enrolled in a single centre, randomised, single-dose, open-label, 2-way crossover study, with a minimum washout period of 7 days, while for the 5 mg study, 42 healthy subjects were included in another study with a similar design. For both studies, plasma samples were collected up to 24 h post-dosing and drug levels were determined by reverse liquid chromatography and detected by tandem mass spectrometry detection.Pharmacokinetic parameters used for bioequivalence assessment, area under the concentration-time curve from time zero to time of last non-zero concentration (AUC0-t) and from time zero to infinity (AUC0-inf) and maximum observed concentration (Cmax), were determined from the drug concentration data using non-compartmental analysis.In the 10 mg study, the 90% confidence intervals obtained by analysis of variance were 99.62-120.51% for Cmax, 102.25-117.37% for AUC0-t and 101.96-116.67% for AUC0-inf, which were within the predefined acceptable range of 80.00-125.00%.In the 5 mg study, the 90% confidence intervals were 91.14-98.46% for Cmax, 93.02-98.42% for AUC0-t and 93.09-98.63% for AUC0-inf, which were within the predefined acceptable range of 80.00-125.00%.Bioequivalence between formulations was concluded both in terms of rate and extent of absorption for both strengths.

Concepts: Pharmacology, Mass spectrometry, Analytical chemistry, Normal distribution, Analysis of variance, 0, Tandem mass spectrometry, Pharmaceutical formulation

27

The relation between the approximate number system (ANS) and symbolic number processing skills remains unclear. Some theories assume that children acquire the numerical meaning of symbols by mapping them onto the preexisting ANS. Others suggest that in addition to the ANS, children also develop a separate, exact representational system for symbolic number processing. In the current study, we contribute to this debate by investigating whether the nonsymbolic number processing of kindergarteners is predictive for symbolic number processing. Results revealed no association between the accuracy of the kindergarteners on a nonsymbolic number comparison task and their performance on the symbolic comparison task six months later, suggesting that there are two distinct representational systems for the ANS and numerical symbols.

Concepts: Mathematics, Number, Real number, Set theory, 0, Numeral system, Concepts, Number system

25

A series of pentacoordinate Ni(ii) complexes of the general formula [Ni(L5)] () with various pentadentate Schiff base ligands H2L5 (originating in a condensation of aromatic ortho-hydroxy-aldehydes and aliphatic triamines) was synthesized and characterized by X-ray structure analysis and magnetometry. The alternations of substituents on the H2L parent ligand resulted in the complexes with the geometry varying between the square-pyramid and trigonal-bipyramid. In the compounds whose chromophore geometry is closer to a trigonal-bipyramid, a large and negative uniaxial anisotropy (D = -64 cm(-1)) was identified. Moreover, the simple linear expression for the axial zero-field splitting (ZFS) parameter, D/cm(-1) = 32.7(4.8) - 151(10)τ, was proposed, where τ (in degrees) stands for the Addison parameter. The results of magnetic analysis were also supported by ab initio CASSCF/NEVPT2 calculations of the ZFS splitting parameters D and E, and g tensors. Despite large and negative D-values of the reported compounds, slow relaxation of magnetization was not observed either in zero or non-zero static magnetic field, thus no single-molecule magnetic behaviour was detected.

Concepts: Magnetic field, Earth's magnetic field, Magnetism, Magnetic moment, Benzene, Permeability, 0, Schiff base

25

Drosophila suzukii is a major pest of cherry in the western United States. We evaluated whether the addition of sugary baits could improve the efficacy of two classes of insecticides not considered to be sufficiently effective for this pest, diamides and spinosyns, in laboratory and field trials in cherry.

Concepts: Insect, United States, Algebraic structure, Real number, 0, Integer, Insecticide, Commutativity