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A Bifan Motif Shaped by ArsR1, ArsR2, and Their Cognate Promoters Frames Arsenic Tolerance of .

Front Microbiol 2021 12;12:641440. Epub 2021 Mar 12.

Systems Biology Department, Centro Nacional de Biotecnología-CSIC, Madrid, Spain.

Prokaryotic tolerance to inorganic arsenic is a widespread trait habitually determined by operons encoding an As (III)-responsive repressor (ArsR), an As (V)-reductase (ArsC), and an As (III)-export pump (ArsB), often accompanied by other complementary genes. Enigmatically, the genomes of many environmental bacteria typically contain two or more copies of this basic genetic device . To shed some light on the logic of such apparently unnecessary duplication(s) we have inspected the regulation-together and by separate-of the two clusters borne by the soil bacterium strain KT2440, in particular the cross talk between the two repressors ArsR1/ArsR2 and the respective promoters. Read More

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Adjudicating Between Local and Global Architectures of Predictive Processing in the Subcortical Auditory Pathway.

Front Neural Circuits 2021 12;15:644743. Epub 2021 Mar 12.

Chair of Cognitive and Clinical Neuroscience, Faculty of Psychology, Technische Universität Dresden, Dresden, Germany.

Predictive processing, a leading theoretical framework for sensory processing, suggests that the brain constantly generates predictions on the sensory world and that perception emerges from the comparison between these predictions and the actual sensory input. This requires two distinct neural elements: generative units, which encode the model of the sensory world; and prediction error units, which compare these predictions against the sensory input. Although predictive processing is generally portrayed as a theory of cerebral cortex function, animal and human studies over the last decade have robustly shown the ubiquitous presence of prediction error responses in several nuclei of the auditory, somatosensory, and visual subcortical pathways. Read More

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Atypical Genetic Basis of Pyrazinamide Resistance in Mono-resistant .

Antimicrob Agents Chemother 2021 Mar 15. Epub 2021 Mar 15.

Laboratory for Pathogenesis of Clinical Drug Resistance and Persistence, School of Public Health, San Diego State University, San Diego, CA, USA

Pyrazinamide (PZA) is a widely used antitubercular chemotherapeutic. Typically, PZA resistance (PZA-R) emerges in strains with existing resistance to isoniazid and rifampicin (MDR) and is conferred by loss-of-function mutations that inhibit conversion to its active form, Pyrazinoic acid (POA). PZA-R departing from this canonical scenario is poorly understood. Read More

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Evolution towards Linguistic Coherence in Naming Game With Migrating Agents.

Entropy (Basel) 2021 Feb 28;23(3). Epub 2021 Feb 28.

Faculty of Physics, Adam Mickiewicz University in Poznań, 61-614 Poznań, Poland.

As an integral part of our culture and way of life, language is intricately related to the migrations of people. To understand whether and how migration shapes language formation processes, we examine the dynamics of the naming game with migrating agents. (i) When all agents may migrate, the dynamics generates effective surface tension that drives the coarsening. Read More

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February 2021

Iron limitation by transferrin promotes simultaneous cheating of pyoverdine and exoprotease in Pseudomonas aeruginosa.

ISME J 2021 Mar 2. Epub 2021 Mar 2.

Departamento de Microbiología y Parasitología, Facultad de Medicina, Universidad Nacional Autónoma de México, Mexico City, Mexico.

Pseudomonas aeruginosa is a primary bacterial model to study cooperative behaviors because it yields exoproducts such as siderophores and exoproteases that act as public goods and can be exploited by selfish nonproducers behaving as social cheaters. Iron-limited growth medium, mainly casamino acids medium supplemented with transferrin, is typically used to isolate and study nonproducer mutants of the siderophore pyoverdine. However, using a protein as the iron chelator could inadvertently select mutants unable to produce exoproteases, since these enzymes can degrade the transferrin to facilitate iron release. Read More

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Unravelling the chemical exposome in cohort studies: routes explored and steps to become comprehensive.

Environ Sci Eur 2021 11;33(1):17. Epub 2021 Feb 11.

Helmholtz Centre for Environmental Research GmbH - UFZ, Permoserstraße 15, 04318 Leipzig, Germany.

Environmental factors contribute to the risk for adverse health outcomes against a background of genetic predisposition. Among these factors, chemical exposures may substantially contribute to disease risk and adverse outcomes. In fact, epidemiological cohort studies have established associations between exposure against individual chemicals and adverse health effects. Read More

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February 2021

Electroencephalography measures of relative power and coherence as reaching skill emerges in infants born preterm.

Sci Rep 2021 Feb 11;11(1):3609. Epub 2021 Feb 11.

Division of Research on Children, Youth, and Families, Children's Hospital Los Angeles, Los Angeles, USA.

Electroencephalography (EEG) measures of relative power and coherence are associated with motor experience in infants with typical development, but these relationships have not been assessed in infants born preterm. The goal of our study was to investigate the changing patterns of relative power and coherence in the alpha band during resting state EEG in infants born preterm as they developed the skill of reaching. We collected monthly longitudinal data from fourteen infants born preterm between the adjusted ages of 56 and 295 days for a total of 37 sessions of EEG data. Read More

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February 2021

Comparative Mapping of the Macrochromosomes of Eight Avian Species Provides Further Insight into Their Phylogenetic Relationships and Avian Karyotype Evolution.

Cells 2021 Feb 9;10(2). Epub 2021 Feb 9.

School of Biosciences, University of Kent, Canterbury CT2 7NJ, UK.

Avian genomes typically consist of ~10 pairs of macro- and ~30 pairs of microchromosomes. While inter-chromosomally, a pattern emerges of very little change (with notable exceptions) throughout evolution, intrachromosomal changes remain relatively poorly studied. To rectify this, here we use a pan-avian universally hybridising set of 74 chicken bacterial artificial chromosome (BAC) probes on the macrochromosomes of eight bird species: common blackbird, Atlantic canary, Eurasian woodcock, helmeted guinea fowl, houbara bustard, mallard duck, and rock dove. Read More

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February 2021

NonREM Disorders of Arousal and Related Parasomnias: an Updated Review.

Neurotherapeutics 2021 Feb 1. Epub 2021 Feb 1.

Department of Neurology, Sleep Disorders Center, University of Minnesota Medical Center, Minneapolis, MN, USA.

Parasomnias are abnormal behaviors and/or experiences emanating from or associated with sleep typically manifesting as motor movements of varying semiology. We discuss mainly nonrapid eye movement sleep and related parasomnias in this article. Sleepwalking (SW), sleep terrors (ST), confusional arousals, and related disorders result from an incomplete dissociation of wakefulness from nonrapid eye movement (NREM) sleep. Read More

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February 2021

Rapid learning of object names in dogs.

Sci Rep 2021 Jan 26;11(1):2222. Epub 2021 Jan 26.

Department of Ethology, Eötvös Loránd University, Budapest, Hungary.

Learning object names after few exposures, is thought to be a typically human capacity. Previous accounts of similar skills in dogs did not include control testing procedures, leaving unanswered the question whether this ability is uniquely human. To investigate the presence of the capacity to rapidly learn words in dogs, we tested object-name learning after four exposures in two dogs with knowledge of multiple toy-names. Read More

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January 2021

Utilitarian Principlism as a Framework for Crisis Healthcare Ethics.

HEC Forum 2021 Jan 15. Epub 2021 Jan 15.

Department of Pediatrics, Division of Critical Care Medicine, Center for Bioethics and Medical Humanities, University of Mississippi Medical Center, 2500 North State St., Jackson, MS, 39216, USA.

This paper introduces the model of Utilitarian Principlism as a framework for crisis healthcare ethics. In modern Western medicine, during non-crisis times, principlism provides the four guiding principles in biomedical ethics-autonomy, nonmaleficence, beneficence, and justice; autonomy typically emerges as the decisive principle. The physician-patient relationship is a deontological construct in which the physician's primary duty is to the individual patient and the individual patient is paramount. Read More

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January 2021

Heterogeneity of Research Results: A New Perspective From Which to Assess and Promote Progress in Psychological Science.

Perspect Psychol Sci 2021 Mar 5;16(2):358-376. Epub 2021 Jan 5.

Department of Psychology, Northumbria University.

Heterogeneity emerges when multiple close or conceptual replications on the same subject produce results that vary more than expected from the sampling error. Here we argue that unexplained heterogeneity reflects a lack of coherence between the concepts applied and data observed and therefore a lack of understanding of the subject matter. Typical levels of heterogeneity thus offer a useful but neglected perspective on the levels of understanding achieved in psychological science. Read More

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Non-equilibrium statistical physics, transitory epigenetic landscapes, and cell fate decision dynamics.

Math Biosci Eng 2020 11;17(6):7916-7930

School of BioScience, University of Melbourne, Melbourne, Parkville 3010, VIC, Australia.

Statistical physics provides a useful perspective for the analysis of many complex systems; it allows us to relate microscopic fluctuations to macroscopic observations. Developmental biology, but also cell biology more generally, are examples where apparently robust behaviour emerges from highly complex and stochastic sub-cellular processes. Here we attempt to make connections between different theoretical perspectives to gain qualitative insights into the types of cell-fate decision making processes that are at the heart of stem cell and developmental biology. Read More

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November 2020

The End of a Classical Ontology for Quantum Mechanics?

Authors:
Peter W Evans

Entropy (Basel) 2020 Dec 24;23(1). Epub 2020 Dec 24.

School of Historical and Philosophical Inquiry, University of Queensland, St Lucia, QLD 4072, Australia.

In this paper, I argue that the Shrapnel-Costa no-go theorem undermines the last remaining viability of the view that the fundamental ontology of quantum mechanics is essentially classical: that is, the view that physical reality is underpinned by objectively real, counterfactually definite, uniquely spatiotemporally defined, local, dynamical entities with determinate valued properties, and where typically 'quantum' behaviour emerges as a function of our own in-principle ignorance of such entities. Call this view Einstein-Bell realism. One can show that the causally symmetric local hidden variable approach to interpreting quantum theory is the most natural interpretation that follows from Einstein-Bell realism, where causal symmetry plays a significant role in circumventing the nonclassical consequences of the traditional no-go theorems. Read More

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December 2020

Meta-control of the exploration-exploitation dilemma emerges from probabilistic inference over a hierarchy of time scales.

Cogn Affect Behav Neurosci 2020 Dec 28. Epub 2020 Dec 28.

Chair of Neuroimaging, Faculty of Psychology, Technische Universität Dresden, 01062, Dresden, Germany.

Cognitive control is typically understood as a set of mechanisms that enable humans to reach goals that require integrating the consequences of actions over longer time scales. Importantly, using routine behaviour or making choices beneficial only at short time scales would prevent one from attaining these goals. During the past two decades, researchers have proposed various computational cognitive models that successfully account for behaviour related to cognitive control in a wide range of laboratory tasks. Read More

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December 2020

It is all relative: Contextual influences on boredom and neural correlates of regulatory processes.

Psychophysiology 2021 Mar 14;58(3):e13746. Epub 2020 Dec 14.

Department of Human Development, Washington State University, Pullman, WA, USA.

Interest in the influences on and strategies to mitigate boredom has grown immensely. Boredom emerges in contexts in which people have difficulty paying attention, such as underchallenging relative to optimally challenging conditions. The current study probed contextual influences on peoples' experience of boredom by manipulating the order with which people performed easy and optimally challenging conditions of a task (N = 113). Read More

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Interrogating the Interplay between Hydrogen and Halogen Bonding in Graphitic Carbon Nitride Building Blocks.

J Phys Chem A 2020 Dec 12;124(51):10817-10825. Epub 2020 Dec 12.

Department of Chemistry and Biochemistry, Baylor University, One Bear Place #97348, Waco, Texas 76798-7348, United States.

Two graphitic carbon nitride (-CN) molecular building blocks designed for halogen bond driven assembly are evaluated through computational quantum chemistry. Unlike those typically reported in the literature, these -CN-based acceptors each offer three unique sites for halogen bond formation, which when introduced to their donor counterparts, lead to 1:1, 2:1, and 3:1 donor-acceptor complexes. Although halogen bonding interactions are present in all donor-acceptor complexes considered in the work, intermolecular hydrogen bonding emerges in complexes in which an iodine-based donor is directly involved. Read More

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December 2020

Kimura's disease: a rare cause of facial mass in a caucasian male patient.

BJR Case Rep 2020 Dec 28;6(4):20200099. Epub 2020 Aug 28.

Centro Hospitalar de São João, Alameda Prof. Hernâni Monteiro, Porto, Portugal.

Kimura's disease is an uncommon inflammatory disorder of unclear aetiology, mainly affecting young Asian descent males among their second and fourth decades of life. The disease typically emerges as a long-standing and painless subcutaneous mass lesion in the head and neck region, frequently associated with swelling of major salivary glands, particularly the parotid gland, and regional lymphadenopathy. Peripheral eosinophilia and high serum immunoglobulin E are also characteristic findings. Read More

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December 2020

Entropy Derived from Causality.

Authors:
Roland Riek

Entropy (Basel) 2020 Jun 10;22(6). Epub 2020 Jun 10.

Laboratory of Physical Chemistry, ETH Zuerich, Wolfgang-Pauli-Strasse 10, HCI F 225, CH-8093 Zurich, Switzerland.

The second law of thermodynamics, with its positive change of entropy for a system not in equilibrium, defines an arrow of time. Interestingly, also, causality, which is the connection between a cause and an effect, requests a direction of time by definition. It is noted that no other standard physical theories show this property. Read More

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Inferring What to Do (And What Not to).

Authors:
Thomas Parr

Entropy (Basel) 2020 May 11;22(5). Epub 2020 May 11.

Wellcome Centre for Human Neuroimaging, University College London, 12 Queen Square, London WC1N 3BG, UK.

In recent years, the "planning as inference" paradigm has become central to the study of behaviour. The advance offered by this is the formalisation of motivation as a prior belief about "how I am going to act". This paper provides an overview of the factors that contribute to this prior. Read More

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The Impact of Age on the Association Between Physical Activity and White Matter Integrity in Cognitively Healthy Older Adults.

Front Aging Neurosci 2020 5;12:579470. Epub 2020 Nov 5.

Department of Psychiatry and Psychotherapy, University Medical Center Mainz, Mainz, Germany.

Cognition emerges from coordinated processing among distributed cortical brain regions, enabled through interconnected white matter networks. Cortical disconnection caused by age-related decline in white matter integrity (WMI) is likely to contribute to age-related cognitive decline. Physical activity (PA) has been suggested to have beneficial effects on white matter structure. Read More

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November 2020

Insights into the model of non-perfect osmometer cells for cryopreservation: A parametric sweep analysis.

Cryobiology 2020 Nov 27. Epub 2020 Nov 27.

Dipartimento di Ingegneria Meccanica, Chimica e Dei Materiali, Facoltà di Ingegneria e Architettura, Università Degli Studi di Cagliari, Via Marengo 2, 09123, Cagliari, Italy. Electronic address:

Recently, a mathematical model able to describe the non-perfect osmotic behavior of cells during cryopreservation was proposed. The model improves the two-parameter formalism typically adopted in cryopreservation literature by allowing the transmembrane permeation of ions/salt, through the temporary opening of mechanosensitive channels whenever membrane stretching occurs: cells can reach an equilibrium volume different from the initial one, when isotonic conditions are re-established after contacting with impermeant or permeant solutes, such as sucrose or a cryoprotectant agent like dimethyl sulfoxide, respectively. Although the model was conceived as a conservative development of the two-parameter formalism to avoid over-parameterization, a complex picture of the system emerges. Read More

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November 2020

Behçet's Disease: Different Systemic Manifestations at Different Ages.

Eurasian J Med 2020 Oct 2;52(3):304-306. Epub 2020 Jun 2.

Department of Pulmonary Disease, Ataturk University School of Medicine, Erzurum, Turkey.

Behçet's disease, an inflammatory condition, can involve various systems. The disease usually manifests with dermatologic and ocular signs but can also cause serious symptoms due to pulmonary or neurologic involvement. Although the onset may occur at any age, it typically emerges in the second to fourth decades of life. Read More

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October 2020

Key role of chemistry versus bias in electrocatalytic oxygen evolution.

Nature 2020 11 18;587(7834):408-413. Epub 2020 Nov 18.

Department of Inorganic Chemistry, Fritz-Haber-Institute of the Max-Planck-Society, Berlin, Germany.

The oxygen evolution reaction has an important role in many alternative-energy schemes because it supplies the protons and electrons required for converting renewable electricity into chemical fuels. Electrocatalysts accelerate the reaction by facilitating the required electron transfer, as well as the formation and rupture of chemical bonds. This involvement in fundamentally different processes results in complex electrochemical kinetics that can be challenging to understand and control, and that typically depends exponentially on overpotential. Read More

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November 2020

Discontinuous transition to loop formation in optimal supply networks.

Nat Commun 2020 11 16;11(1):5796. Epub 2020 Nov 16.

Forschungszentrum Jülich, Institute for Energy and Climate Research (IEK-STE), 52428, Jülich, Germany.

The structure and design of optimal supply networks is an important topic in complex networks research. A fundamental trait of natural and man-made networks is the emergence of loops and the trade-off governing their formation: adding redundant edges to supply networks is costly, yet beneficial for resilience. Loops typically form when costs for new edges are small or inputs uncertain. Read More

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November 2020

Redox-informed models of global biogeochemical cycles.

Nat Commun 2020 11 10;11(1):5680. Epub 2020 Nov 10.

Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA, 02139, USA.

Microbial activity mediates the fluxes of greenhouse gases. However, in the global models of the marine and terrestrial biospheres used for climate change projections, typically only photosynthetic microbial activity is resolved mechanistically. To move forward, we argue that global biogeochemical models need a theoretically grounded framework with which to constrain parameterizations of diverse microbial metabolisms. Read More

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November 2020

Progress Toward Global Eradication of Dracunculiasis, January 2019-June 2020.

MMWR Morb Mortal Wkly Rep 2020 Oct 30;69(43):1563-1568. Epub 2020 Oct 30.

Dracunculiasis (Guinea worm disease) is caused by the parasite Dracunculus medinensis and is acquired by drinking water containing copepods (water fleas) infected with D. medinensis larvae. The worm typically emerges through the skin on a lower limb approximately 1 year after infection, resulting in pain and disability (1). Read More

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October 2020

Stochasticity in Single-Entity Electrochemistry.

Curr Opin Electrochem 2021 Feb 6;25. Epub 2020 Sep 6.

Department of Chemistry & Biochemistry, University of Arkansas, Fayetteville, AR 72701.

Most electrochemical processes are stochastic and discrete in nature. Yet experimental observables, e.g. Read More

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February 2021

Visuo-haptic transfer for object recognition in children with peripheral visual impairment.

Vision Res 2021 Jan 15;178:12-17. Epub 2020 Oct 15.

Department of Developmental Neuroscience, IRCCS Stella Maris Foundation, Pisa, Italy. Electronic address:

It is well known how early visual experience is critical for the development of multisensory processing abilities, and for this reason an early vision impairment could hinder the transfer of different sensory information during the exploration and recognition of the surrounding environment. Recently, we verified that visuo-haptic transfer for object recognition emerges early in typically developing children but matures slowly during the school-age period. Subsequently we verified the presence of a slower trend of development in unisensory and multisensory skills in children with early abnormal motor and sensory experiences due to brain lesions. Read More

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January 2021

Agent-based simulation of collective cooperation: from experiment to model.

J R Soc Interface 2020 10 7;17(171):20200396. Epub 2020 Oct 7.

University of Sussex, School of Psychology, BN1 9RH, Brighton, UK.

Simulation models of pedestrian dynamics have become an invaluable tool for evacuation planning. Typically, crowds are assumed to stream unidirectionally towards a safe area. Simulated agents avoid collisions through mechanisms that belong to each individual, such as being repelled from each other by imaginary forces. Read More

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October 2020