SciCombinator

Discover the most talked about and latest scientific content & concepts.

Concept: Existence

454

Nutrient timing is a popular nutritional strategy involves the consumption of combinations of nutrients–primarily protein and carbohydrate–in and around an exercise session. Some have claimed that this approach can produce dramatic improvements in body composition. It has even been postulated that the timing of nutritional consumption may be more important than the absolute daily intake of nutrients. The post-exercise period is widely considered the most critical part of nutrient timing. Theoretically, consuming the proper ratio of nutrients during this time not only initiates the rebuilding of damaged muscle tissue and restoration of energy reserves, but it does so in a supercompensated fashion that enhances both body composition and exercise performance. Several researchers have made reference to an anabolic “window of opportunity” whereby a limited time exists after training to optimize training-related muscular adaptations. However, the importance - and even the existence - of a post-exercise ‘window’ can vary according to a number of factors. Not only is nutrient timing research open to question in terms of applicability, but recent evidence has directly challenged the classical view of the relevance of post-exercise nutritional intake with respect to anabolism. Therefore, the purpose of this paper will be twofold: 1) to review the existing literature on the effects of nutrient timing with respect to post-exercise muscular adaptations, and; 2) to draw relevant conclusions that allow practical, evidence-based nutritional recommendations to be made for maximizing the anabolic response to exercise.

Concepts: Metabolism, Nutrition, Muscle, Nutrient, Vitamin, Ontology, Muscular system, Existence

171

Manual curation of data from the biomedical literature is a rate-limiting factor for many expert curated databases. Despite the continuing advances in biomedical text mining and the pressing needs of biocurators for better tools, few existing text-mining tools have been successfully integrated into production literature curation systems such as those used by the expert curated databases. To close this gap and better understand all aspects of literature curation, we invited submissions of written descriptions of curation workflows from expert curated databases for the BioCreative 2012 Workshop Track II. We received seven qualified contributions, primarily from model organism databases. Based on these descriptions, we identified commonalities and differences across the workflows, the common ontologies and controlled vocabularies used and the current and desired uses of text mining for biocuration. Compared to a survey done in 2009, our 2012 results show that many more databases are now using text mining in parts of their curation workflows. In addition, the workshop participants identified text-mining aids for finding gene names and symbols (gene indexing), prioritization of documents for curation (document triage) and ontology concept assignment as those most desired by the biocurators. Database URL: http://www.biocreative.org/tasks/bc-workshop-2012/workflow/

Concepts: Bioinformatics, Biology, Ontology, Controlled vocabulary, Writing, Data mining, Existence

125

The term “adrenal fatigue” (“AF”) has been used by some doctors, healthcare providers, and the general media to describe an alleged condition caused by chronic exposure to stressful situations. Despite this, “AF” has not been recognized by any Endocrinology society, who claim there is no hard evidence for the existence. The aim of this systematic review is to verify whether there is substantiation for “AF”.

Concepts: Health care provider, Medicine, Existence, Patent, Debut albums, Evidence, Media, Illinois

31

Multiple-homicide school shootings are rare events, but when they happen they significantly impact individuals, the school and the community. We focus on multiple-homicide incidents and identified mental health issues of shooters. To date, studies of school shootings have concluded that no reliable profile of a shooter exists, so risk should be assessed using comprehensive threat assessment protocols. Existing studies primarily utilize retrospective case histories or media accounts. The field requires more empirical and systematic research on all types of school shootings including single victim incidents, those that result in injury but not death and those that are successfully averted. We discuss current policies and practices related to school shootings and the role of mental health professionals in assessing risk and supporting surviving victims.

Concepts: Assessment, Existence, Victim

28

Audience segmentation is a useful tool for designing effective campaigns. Further, the efficiency promised in diffusion science rests to some degree on the existence of adopter categories that can be identified and used to strategically disseminate prevention innovations. This study investigates the potential to identify adopter categories in potential recipients (n = 127) of an innovation to prevent food shortages in Mozambique. A 5-class model was found using latent class analysis, but it showed important differences from existing descriptions of adopter categories. Implications for theory and practice are discussed.

Concepts: Economics, Ontology, Existence, Metaphysics, Reality, Innovation, Diffusion of innovations, Category of being

25

The literature contains confusing and opposing views about the naming, prevalence, anatomic structure, and clinical significance of the arcade of Struthers. The conflicting rates of arcade (between 0% and 100%) prevalence found in the literature may be due to the varying definition of the arcade among the authors, as well as the dissection method.The present study aims to examine the structure to determine whether or not the arcade of Struthers exists through an anatomic dissection study of a fresh human cadaver and seeks to compare its findings with those in the literature. Twenty arms from fresh frozen cadavers were dissected. An arcade of Struthers was not found in any specimen. Study concluded that its existence is unproven, and the arcade of Struthers does not exist.

Concepts: Biology, Ontology, Anatomy, Existence, Reality, Cadaver, Dissection, Plato

23

We consider the asymmetric active coupler (AAC) consisting of two coupled dissimilar waveguides with gain and loss. We show that under generic conditions, not restricted by parity-time symmetry, there exist finite-power, constant-intensity nonlinear supermodes (NS), resulting from the balance between gain, loss, nonlinearity, coupling and dissimilarity. The system is shown to possess non-reciprocal dynamics enabling directed power transport functionality.

Concepts: Existence, Nonlinear system

17

The positive deviance approach focuses on those who demonstrate exceptional performance, despite facing the same constraints as others. ‘Positive deviants’ are identified and hypotheses about how they succeed are generated. These hypotheses are tested and then disseminated within the wider community. The positive deviance approach is being increasingly applied within healthcare organisations, although limited guidance exists and different methods, of varying quality, are used. This paper systematically reviews healthcare applications of the positive deviance approach to explore how positive deviance is defined, the quality of existing applications and the methods used within them, including the extent to which staff and patients are involved.

Concepts: Existence, Metaphysics, Being

16

The spectral gap-the energy difference between the ground state and first excited state of a system-is central to quantum many-body physics. Many challenging open problems, such as the Haldane conjecture, the question of the existence of gapped topological spin liquid phases, and the Yang-Mills gap conjecture, concern spectral gaps. These and other problems are particular cases of the general spectral gap problem: given the Hamiltonian of a quantum many-body system, is it gapped or gapless? Here we prove that this is an undecidable problem. Specifically, we construct families of quantum spin systems on a two-dimensional lattice with translationally invariant, nearest-neighbour interactions, for which the spectral gap problem is undecidable. This result extends to undecidability of other low-energy properties, such as the existence of algebraically decaying ground-state correlations. The proof combines Hamiltonian complexity techniques with aperiodic tilings, to construct a Hamiltonian whose ground state encodes the evolution of a quantum phase-estimation algorithm followed by a universal Turing machine. The spectral gap depends on the outcome of the corresponding ‘halting problem’. Our result implies that there exists no algorithm to determine whether an arbitrary model is gapped or gapless, and that there exist models for which the presence or absence of a spectral gap is independent of the axioms of mathematics.

Concepts: Mathematics, Quantum mechanics, Existence, Quantum state, Standard Model, Halting problem, Turing machine, Undecidable problem

15

While it is now recognized that autism spectrum disorder (ASD) is typically a life-long condition, there exist only a handful of systematic studies on middle-aged and older adults with this condition.

Concepts: Middle age, Old age, Autism, Pervasive developmental disorder, Existence, Asperger syndrome, Autism spectrum, PDD-NOS