Association of chronotype and social jetlag with human non-verbal intelligence

The aim of this study was to evaluate the effects of chronotype and social jetlag (SJL) on intelligence. Subjects were aged 14–25 years (n = 1008). A significant effect of intelligence on academic performance, as measured by the Raven’s Standard Progressive Matrices test, was found (F_2,917 = 11.75, P < 0.0001, η² = 0.03). When SJL was less than 2 hours, the intelligence of people with late chronotype was found to be higher than that of subjects with early and intermediate chronotypes (F_2,305 = 3.12, P < 0.05, η² = 0.02). A negative effect of SJL on the results of intelligence testing was noted only in subjects with late chronotype (F_2,536 = 2.61, P < 0.05, η² = 0.02). Our data suggest that people with late chronotype have a higher level of intelligence, but these advantages disappear when SJL ≥2 hours.     

Perspectives on Structural Molecular Biology Visualization: From Past to Present

Visualization has been a key technology in the progress of structural molecular biology for as long as the field has existed. This perspective describes the nature of the visualization process in structural studies, how it has evolved over the years, and its relationship to the changes in technology that have supported and driven it. It focuses on how technical advances have changed the way we look at and interact with molecular structure, and how structural biology has fostered and challenged that technology.     

Testing Refrigeration Trucks for the Emergency Evacuation of Companion Animals

The purpose of this study was to quantify the changes in oxygen (O₂) and carbon dioxide (CO₂) in sealed refrigerator trucks scheduled to be used for transporting companion animals (dogs and cats) during an emergency evacuation. A total of 122 nonhuman animals (total weight = 1,248 kg) housed in individual crates were loaded into a 16-m refrigeration truck. Once they were loaded, the doors were closed and the percentages of O₂ and CO₂ were measured every 5 min by O₂ and CO₂ analyzers, and they were used to quantify the changes in gas pressure in the sealed truck. CO₂ had a much higher-than-predicted increase, and O₂ had a higher-than-predicted decrease. These 2 pressures in combination with the functionality of the respiratory system will limit the animal's ability to load O₂, and over time, they will initiate asphyxia or suffocation. Over time, the partial pressure of oxygen (P_O2) in the sealed truck will decrease, causing hypoxia, and the partial pressure of carbon dioxide (P_CO2) will increase, causing hypercapnia.     

Pediatric diagnosis not made until adulthood: A case of Wolf–Hirschhorn syndrome

Wolf–Hirschhorn syndrome is a well-known clinical entity caused by a terminal deletion of the short arm of chromosome 4 (4p-). The diagnosis is usually made in childhood because of the pathognomonic facial dysmorphism, multi-organ involvement and seizures. Epilepsy is a major medical complication during the first years of life, with seizures typically being frequent, although they tend to improve or cease with age. We report on a woman diagnosed with WHS in her thirties by array-CGH. She presents with milder dysmorphic features, recognized by stereophotogrammetry and seizures persistent in adulthood.     

Procurement,commissioning and QA of AI based solutions: An MPE’s perspective on introducing AI in clinical practice

PurposeIn this study, we propose a framework to help the MPE take up a unique and important role at the introduction of AI solutions in clinical practice, and more in particular at procurement, acceptance, commissioning and QA.Material and methodsThe steps for the introduction of Medical Radiological Equipment in a hospital setting were extrapolated to AI tools. Literature review and in-house experience was added to prepare similar, yet dedicated test methods.ResultsProcurement starts from the clinical cases to be solved and is usually a complex process with many stakeholders and possibly many candidate AI solutions. Specific KPIs and metrics need to be defined. Acceptance testing follows, to verify the installation and test for critical exams. Commissioning should test the suitability of the AI tool for the intended use in the local institution. Results may be predicted from peer reviewed papers that treat representative populations. If not available, local data sets can be prepared to assess the KPIs, or ‘virtual clinical trials’ could be used to create large, simulated test data sets. Quality assurance must be performed periodically to verify if KPIs are stable, especially if the software is upscaled or upgraded, and as soon as self-learning AI tools would enter the medical practice.DiscussionMPEs are well placed to bridge between manufacturer and medical team and help from procurement up to reporting to the management board. More work is needed to establish consolidated test protocols.     

Recent progress on the prospective application of machine learning to structure-based virtual screening

As more bioactivity and protein structure data become available, scoring functions (SFs) using machine learning (ML) to leverage these data sets continue to gain further accuracy and broader applicability. Advances in our understanding of the optimal ways to train and evaluate these ML-based SFs have introduced further improvements. One of these advances is how to select the most suitable decoys (molecules assumed inactive) to train or test an ML-based SF on a given target. We also review the latest applications of ML-based SFs for prospective structure-based virtual screening (SBVS), with a focus on the observed improvement over those using classical SFs. Finally, we provide recommendations for future prospective SBVS studies based on the findings of recent methodological studies.     

On the Structural Diversity and Individuality of Polymorphic Amyloid Protein Assemblies

The prediction of highly ordered three-dimensional structures of amyloid protein fibrils from the amino acid sequences of their monomeric self-assembly precursors constitutes a challenging and unresolved aspect of the classical protein folding problem. Because of the polymorphic nature of amyloid assembly whereby polypeptide chains of identical amino acid sequences under identical conditions are capable of self-assembly into a spectrum of different fibril structures, the prediction of amyloid structures from an amino acid sequence requires a detailed and holistic understanding of its assembly free energy landscape. The full extent of the structure space accessible to the cross-β molecular architecture of amyloid must also be resolved. Here, we review the current understanding of the diversity and the individuality of amyloid structures, and how the polymorphic landscape of amyloid links to biology and disease phenotypes. We present a comprehensive review of structural models of amyloid fibrils derived by cryo-EM, ssNMR and AFM to date, and discuss the challenges ahead for resolving the structural basis and the biological consequences of polymorphic amyloid assemblies.     

A claim in search of evidence: reply to Manger’s thermogenesis hypothesis of cetacean brain structure

In a recent publication in Biological Reviews, Manger (2006) made the controversial claim that the large brains of cetaceans evolved to generate heat during oceanic cooling in the Oligocene epoch and not, as is the currently accepted view, as a basis for an increase in cognitive or information‐processing capabilities in response to ecological or social pressures. Manger further argued that dolphins and other cetaceans are considerably less intelligent than generally thought. In this review we challenge Manger’s arguments and provide abundant evidence that modern cetacean brains are large in order to support complex cognitive abilities driven by social and ecological forces.     

Determination of the respiration quotient in mammalian cell culture in bicarbonate buffered media

The determination of the respiration quotient (RQ = CER/OUR) has not been used so far as a tool for understanding animal cell metabolism. This is due to problems in measuring the carbon dioxide evolution rate (CER) rather than the oxygen uptake rate (OUR). The determination of the CER is complicated by the use of bicarbonate in the medium. Using liquid and gas balances we have derived an equation for continuous culture to quantify the amount of CO(2) that comes from the bicarbonate in the feed. Under cell-free conditions, values predicted by this equation agree within 4% with the experimental results. In continuous culture using hybridoma cells, the CO(2) from the feed, as determined by an IR-gas analyzer, was found to represent a significant amount of the total measured CO(2) in the off-gas (50% in a suboptimal, and 30% in high-growth medium). Furthermore, the problem of CO(2) loss from the medium during medium preparation and storage was solved using both a theoretical and an experimental approach. RQ values in continuous culture were evaluated for two different growth media. Small but significant differences in RQ were measured, which were matched by differences in specific antibody rates and other metabolic quotients. In a medium with Primatone RL, an enzymatic hydrolysate of animal cell tissue that causes a more than twofold increase in cell density, the RQ was found to be 1.05, whereas in medium without Primatone RL (but containing amino acids equivalent in composition and concentration to Primatone RL) the RQ was found to be 0.97. We suggest the RQ to be a useful parameter for estimating the physiological state of cells. Its determination could be a suitable tool for both the on-line control of animal cell cultivations and the understanding of cell metabolism. (c) 1995 John Wiley & Sons, Inc.