Task complexity, the Cognition Hypothesis and second language learning and performance

In this paper we describe a taxonomy of task demands which distinguishes between Task Complexity, Task Condition and Task Difficulty. We then describe three theoretical claims and predictions of the Cognition Hypothesis (Robinson 2001, 2003b, 2005a) concerning the effects of task complexity on: (a) language production; (b) interaction and uptake of information available in the input to tasks; and (c) individual differences-task interactions. Finally we summarize the findings of the empirical studies in this special issue which all address one or more of these predictions and point to some directions for continuing, future research into the effects of task complexity on learning and performance.

The spreading of the introduced seaweed Caulerpa taxifolia (Vahl) C. Agardh in the Mediterranean Sea: testing the boat transportation hypothesis

The Spreading of the Introduced Seaweed Caulerpa taxifolia (Vahl) C. Agardh in the Mediterranean Sea: Testing the Boat Transportation Hypothesis

Sex differences in brain plasticity: a new hypothesis for sex ratio bias in autism.

Several observations support the hypothesis that differences in synaptic and regional cerebral plasticity between the sexes account for the high ratio of males to females in autism. First, males are more susceptible than females to perturbations in genes involved in synaptic plasticity. Second, sex-related differences in non-autistic brain structure and function are observed in highly variable regions, namely, the heteromodal associative cortices, and overlap with structural particularities and enhanced activity of perceptual associative regions in autistic individuals. Finally, functional cortical reallocations following brain lesions in non-autistic adults (for example, traumatic brain injury, multiple sclerosis) are sex-dependent. Interactions between genetic sex and hormones may therefore result in higher synaptic and consecutively regional plasticity in perceptual brain areas in males than in females. The onset of autism may largely involve mutations altering synaptic plasticity that create a plastic reaction affecting the most variable and sexually dimorphic brain regions. The sex ratio bias in autism may arise because males have a lower threshold than females for the development of this plastic reaction following a genetic or environmental event.

More evidence concerning the aspect hypothesis: The acquisition of English progressive aspect by Catalan-Spanish instructed learners

A robust finding of studies investigating the Aspect Hypothesis is that learners at early stages of acquisition show a strong preference for using the progressive aspect as associated with activity verbs. As they advance in their acquisition of the second or foreign language, learners move from this prototypical association to associations traditionally considered to be more peripheral (e.g.-ing with accomplishments or achievements). Within this framework, the goal of this paper is to provide further evidence from groups of learners with different proficiency levels with regard to the acquisition of progressive aspect by tutored learners of English who are bilingual Catalan-Spanish. This is done by eliciting data by means of two different task types and by looking at both tokens and types. Our results are consistent with previous research according to which-ing morphology is closely associated with durative lexical aspect, although not necessarily with activity predicates. The study also shows that the type of task has an influence on the frequency and the distribution of learners" progressive forms.

Central serous chorioretinopathy: Recent findings and new physiopathology hypothesis.

Central serous chorioretinopathy (CSCR) is a major cause of vision threat among middle-aged male individuals. Multimodal imaging led to the description of a wide range of CSCR manifestations, and highlighted the contribution of the choroid and pigment epithelium in CSCR pathogenesis. However, the exact molecular mechanisms of CSCR have remained uncertain. The aim of this review is to recapitulate the clinical understanding of CSCR, with an emphasis on the most recent findings on epidemiology, risk factors, clinical and imaging diagnosis, and treatments options. It also gives an overview of the novel mineralocorticoid pathway hypothesis, from animal data to clinical evidences of the biological efficacy of oral mineralocorticoid antagonists in acute and chronic CSCR patients. In rodents, activation of the mineralocorticoid pathway in ocular cells either by intravitreous injection of its specific ligand, aldosterone, or by over-expression of the receptor specifically in the vascular endothelium, induced ocular phenotypes carrying many features of acute CSCR. Molecular mechanisms include expression of the calcium-dependent potassium channel (KCa2.3) in the endothelium of choroidal vessels, inducing subsequent vasodilation. Inappropriate or over-activation of the mineralocorticoid receptor in ocular cells and other tissues (such as brain, vessels) could link CSCR with the known co-morbidities observed in CSCR patients, including hypertension, coronary disease and psychological stress.

Changes in the phenolic content of low density lipoprotein after olive oil consumption in men. A randomized crossover controlled trial

Olive oil decreases the risk of CVD. This effect may be due to the fatty acid profile of the oil, but it may also be due to its antioxidant content which differs depending on the type of olive oil. In this study, the concentrations of oleic acid and antioxidants (phenolic compounds and vitamin E) in plasma and LDL were compared after consumption of three similar olive oils, but with differences in their phenolic content. Thirty healthy volunteers participated in a placebo-controlled, double-blind, crossover, randomized supplementation trial. Virgin, common, and refined olive oils were administered during three periods of 3 weeks separated by a 2-week washout period. Participants were requested to ingest a daily dose of 25 ml raw olive oil, distributed over the three meals of the day, during intervention periods. All three olive oils caused an increase in plasma and LDL oleic acid (P,0·05) content. Olive oils rich in phenolic compounds led to an increase in phenolic compounds in LDL (P,0·005). The concentration of phenolic compounds in LDL was directly correlated with the phenolic concentration in the olive oils. The increase in the phenolic content of LDL could account for the increase of the resistance of LDL to oxidation, and the decrease of the in vivo oxidized LDL, observed in the frame of this trial. Our results support the hypothesis that a daily intake of virgin olive oil promotes protective LDL changes ahead of its oxidation.

Steroid hormones interrelationships in the metabolic syndrome: an introduction to the ponderostat hypothesis

Sexual dimorphism in the metabolic syndrome. The clairvoyant early implication of sex hormones in the characterization of the metabolic syndrome (MS) was detected early, and in accordance with the well-known sex-related main patterns of fat deposition in obesity: gynoid and android. The differences point to a direct implication of androgens and estrogens in the development, properties and maintenance of obesity and, by extension, to the cumulus of diseases grouped in the MS. For a long time, the key issue of the MS, i.e. the metabolic event explaining (and justifying) most of the derangements of the MS, has been considered to be insulin resistance (...)

Lipid mobilization and gluconeogenesis in plants: Do glyoxylate cycle enzyme activities constitute a real cycle? A hypothesis

Glyoxysomes are specialized peroxisomes present in various plant organs such as germinating cotyledons or senescing leaves. They are the site of beta-oxidation and of the glyoxylate cycle. These consecutive pathways are essential to the maintenance of gluconeogenesis initiated by the degradation of reserve or structural lipids. In contrast to mitochondrial beta-oxidation, which is prevalent in animal cells, glyoxysomal beta-oxidation and the glyoxylate cycle have no direct access to the mitochondrial respiratory chain because of the impermeability of the glyoxysomal membrane to the reduced cofactors. The necessity of NAD(+) regeneration can conceivably be fulfilled by membrane redox chains and/or by transmembrane shuttles. Experimental evidence based on the active metabolic roles of higher plant glyoxysomes and yeast peroxisomes suggests the coexistence of two mechanisms, namely a reductase/peroxidase membrane redox chain and a malate/aspartate shuttle susceptible to transfer electrons to the mitochondrial ATP generating system. Such a model interconnects beta-oxidation, the glyoxylate cycle, the respiratory chain and gluconeogenesis in such a way that glyoxysomal malate dehydrogenase is an essential and exclusive component of beta-oxidation (NAD(+) regeneration). Consequently, the classical view of the glyoxylate cycle is superseded by a tentative reactional scheme deprived of cyclic character.

Statistical hypothesis testing and common misinterpretations: should we abandon p-value in forensic science applications?

Many people regard the concept of hypothesis testing as fundamental to inferential statistics. Various schools of thought, in particular frequentist and Bayesian, have promoted radically different solutions for taking a decision about the plausibility of competing hypotheses. Comprehensive philosophical comparisons about their advantages and drawbacks are widely available and continue to span over large debates in the literature. More recently, controversial discussion was initiated by an editorial decision of a scientific journal [1] to refuse any paper submitted for publication containing null hypothesis testing procedures. Since the large majority of papers published in forensic journals propose the evaluation of statistical evidence based on the so called p-values, it is of interest to expose the discussion of this journal's decision within the forensic science community. This paper aims to provide forensic science researchers with a primer on the main concepts and their implications for making informed methodological choices.

Governance mode vs. governance fit: Performance implications of make-or-ally choices for product innovation in the worldwide aircraft industry, 1942-2000

We examine the impact of governance mode and governance fit on performance in make-or-ally decisions. We argue that while horizontal collaboration and autonomous governance have direct and countervailing performance implications, the alignment of make-or-ally choices with the focal firm's resource endowment and the activity's resource requirements leads to better performance. Data on the aircraft industry show that relative to aircraft developed autonomously, collaborative aircraft exhibit greater sales but require longer time-to-market. However, governance fit increases unit sales and reduces time-to-market. We contribute to the alliance and economic organization literatures. (Copyright © 2013 John Wiley & Sons, Ltd.)

Re-visiting the health care luxury good hypothesis: Aggregation, precision, and publication biases?

[cat] Mentre que una creixent literatura que ha examinat la relació entre la renda i la despesa sanitària suggereix que els serveis sanitaris són un be de luxe (elasticitat renda superior a la unitat), aquesta conclusió es contínuament debatuda atesa l'heterogeneïtat dels resultats. Aquest article testa la hipòtesis dels serveis sanitaris com bens de luxe fent server anàlisi de meta- regressió, particularment analitzant l'existència de biaixos de selecció de publicació, precisió així com biaixos d'agregació. Els resultats apunten l'existència d'un biaix de publicació, robust independentment dels controls analitzats. Els biaixos de precisió i agregació semblen tenir un paper en la generació de les estimacions de l'elasticitat renda. Els nostres resultat suggereixen que l'elasticitat renda dels serveis sanitaris un cop corregir pels biaixos esmentat varien entre 0.26 i 0.84, però no podem rebutjar que la elasticitat renda es igual a la unitat en algunes estimacions de l'elasticitat corregides.

Re-visiting the health care luxury good hypothesis: Aggregation, precision, and publication biases?

[cat] Mentre que una creixent literatura que ha examinat la relació entre la renda i la despesa sanitària suggereix que els serveis sanitaris són un be de luxe (elasticitat renda superior a la unitat), aquesta conclusió es contínuament debatuda atesa l'heterogeneïtat dels resultats. Aquest article testa la hipòtesis dels serveis sanitaris com bens de luxe fent server anàlisi de meta- regressió, particularment analitzant l'existència de biaixos de selecció de publicació, precisió així com biaixos d'agregació. Els resultats apunten l'existència d'un biaix de publicació, robust independentment dels controls analitzats. Els biaixos de precisió i agregació semblen tenir un paper en la generació de les estimacions de l'elasticitat renda. Els nostres resultat suggereixen que l'elasticitat renda dels serveis sanitaris un cop corregir pels biaixos esmentat varien entre 0.26 i 0.84, però no podem rebutjar que la elasticitat renda es igual a la unitat en algunes estimacions de l'elasticitat corregides.

A Markov chain analysis of emotional exchange in voice-to-voice communication: Testing for the mimicry hypothesis of emotional contagion

Mimicry is a central plank of the emotional contagion theory; however, it was only tested with facial and postural emotional stimuli. This study explores the existence of mimicry in voice-to-voice communication by analyzing 8,747 sequences of emotional displays between customers and employees in a call-center context. We listened live to 967 telephone inter-actions, registered the sequences of emotional displays, and analyzed them with a Markov chain. We also explored other propositions of emotional contagion theory that were yet to be tested in vocal contexts. Results supported that mimicry is significantly present at all levels. Our findings fill an important gap in the emotional contagion theory; have practical implications regarding voice-to-voice interactions; and open doors for future vocal mimicry research.