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Scholars as allies in the struggle for food systems transformation.

Charles Z Levkoe

Agric Human Values 2021 Apr 9:1-4. Epub 2021 Apr 9.

Department of Health Sciences, Lakehead University, 955 Oliver Rd, Thunder Bay, ON P7B 5E1 Canada.

Molly Anderson's 2020 Presidential Address for the Agriculture and Human Values Society, is a bold call to action that considers the scope and depth of the challenges facing global food systems. This call has particular relevance to scholars who are closely aligned with struggles for food justice and food sovereignty. In this discussion piece, I suggest additional nuance that builds and expands on Anderson's three opportunities for "pushing beyond the boundaries". Read More

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Constraining the atmospheric limb of the plastic cycle.

Proc Natl Acad Sci U S A 2021 Apr;118(16)

Scripps Institution of Oceanography, University of California San Diego, La Jolla, CA 92093.

Plastic pollution is one of the most pressing environmental and social issues of the 21st century. Recent work has highlighted the atmosphere's role in transporting microplastics to remote locations [S. Allen et al. Read More

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Tracing local sources and long-range transport of PM in central Taiwan by using chemical characteristics and Pb isotope ratios.

Sci Rep 2021 Apr 7;11(1):7593. Epub 2021 Apr 7.

Institute of Earth Sciences, Academia Sinica, Taipei, Taiwan.

Central Taiwan is among the most heavily polluted regions in Taiwan because of a complex mixing of local emissions from intense anthropogenic activities with natural dust. Long-range transport (LRT) of pollutants from outside Taiwan also contributes critically to the deterioration of air quality, especially during the northeast monsoon season. To identify the sources of particulate matter < 10 μm (PM) in central Taiwan, this study performed several sampling campaigns, including three local events, one LRT event, and one dust storm event, during the northeast monsoon season of 2018/2019. Read More

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Environmental Correlates of Lyme Disease Emergence in Southwest Virginia, 2005-2014.

J Med Entomol 2021 Apr 7. Epub 2021 Apr 7.

Nicholas School of the Environment, Duke University, Durham, NC.

Lyme disease is the most common tick-borne disease in North America. Though human infection is mostly transmitted in a limited geography, the range has expanded in recent years. One notable area of recent expansion is in the mountainous region of southwestern Virginia. Read More

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Development of a new aerosol barrier mask for mitigation of spread of SARS-CoV-2 and other infectious pathogens.

Respir Med 2021 Mar 29;181:106381. Epub 2021 Mar 29.

Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, 85281, Arizona, USA; School of Engineering for Matter, Transport, and Energy, Arizona State University, Tempe, 85281, Arizona, USA. Electronic address:

The COVID-19 pandemic has caused huge impact on public health and significantly changed our lifestyle. This is due to the fast airborne oro-nasal transmission of SARS-CoV-2 from the infected individuals. The generation of liquid aerosolized particles occurs when the COVID-19 patients speak, sing, cough, sneeze, or simply breathe. Read More

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Time-Lapse Imaging of Neuronal Arborization using Sparse Adeno-Associated Virus Labeling of Genetically Targeted Retinal Cell Populations.

J Vis Exp 2021 Mar 19(169). Epub 2021 Mar 19.

Program for Neuroscience and Mental Health, Hospital for Sick Children; Department of Molecular Genetics, University of Toronto;

Discovering mechanisms that pattern dendritic arbors requires methods to visualize, image, and analyze dendrites during development. The mouse retina is a powerful model system for the investigation of cell type-specific mechanisms of neuronal morphogenesis and connectivity. The organization and composition of retinal subtypes are well-defined, and genetic tools are available to access specific types during development. Read More

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Characterizing neuroanatomic heterogeneity in people with and without ADHD based on subcortical brain volumes.

J Child Psychol Psychiatry 2021 Mar 30. Epub 2021 Mar 30.

Department of Human Genetics, Donders Institute for Brain, Cognition and Behaviour, Radboud University Medical Center, Nijmegen, The Netherlands.

Background: Attention-deficit/hyperactivity disorder (ADHD) is a prevalent neurodevelopmental disorder. Neuroanatomic heterogeneity limits our understanding of ADHD's etiology. This study aimed to parse heterogeneity of ADHD and to determine whether patient subgroups could be discerned based on subcortical brain volumes. Read More

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Antiviral drug screen identifies DNA-damage response inhibitor as potent blocker of SARS-CoV-2 replication.

Cell Rep 2021 04 18;35(1):108940. Epub 2021 Mar 18.

Department of Molecular and Medical Pharmacology, University of California, Los Angeles, Los Angeles, CA 90095, USA; Eli and Edythe Broad Center of Regenerative Medicine and Stem Cell Research, UCLA, Los Angeles, CA 90095, USA; California NanoSystems Institute, University of California, Los Angeles, Los Angeles, CA 90095, USA. Electronic address:

SARS-CoV-2 has currently precipitated the COVID-19 global health crisis. We developed a medium-throughput drug-screening system and identified a small-molecule library of 34 of 430 protein kinase inhibitors that were capable of inhibiting the SARS-CoV-2 cytopathic effect in human epithelial cells. These drug inhibitors are in various stages of clinical trials. Read More

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Loose programming of GIS workflows with geo-analytical concepts.

Trans GIS 2021 Feb 26;25(1):424-449. Epub 2020 Oct 26.

Department of Human Geography and Spatial Planning Utrecht University Utrecht the Netherlands.

Loose programming enables analysts to program with concepts instead of procedural code. Data transformations are left underspecified, leaving out procedural details and exploiting knowledge about the applicability of functions to data types. To synthesize workflows of high quality for a geo-analytical task, the semantic type system needs to reflect knowledge of geographic information systems (GIS) at a level that is deep enough to capture geo-analytical concepts and intentions, yet shallow enough to generalize over GIS implementations. Read More

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February 2021

The connectome predicts resting-state functional connectivity across the Drosophila brain.

Curr Biol 2021 Mar 23. Epub 2021 Mar 23.

Department of Neurobiology, Stanford University, Stanford, CA 94103, USA. Electronic address:

Anatomical connectivity can constrain both a neural circuit's function and its underlying computation. This principle has been demonstrated for many small, defined neural circuits. For example, connectome reconstructions have informed models for direction selectivity in the vertebrate retina as well as the Drosophila visual system. Read More

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Constraints on Dark Matter Properties from Observations of Milky Way Satellite Galaxies.

Phys Rev Lett 2021 Mar;126(9):091101

Fermi National Accelerator Laboratory, P.O. Box 500, Batavia, Illinois 60510, USA.

We perform a comprehensive study of Milky Way (MW) satellite galaxies to constrain the fundamental properties of dark matter (DM). This analysis fully incorporates inhomogeneities in the spatial distribution and detectability of MW satellites and marginalizes over uncertainties in the mapping between galaxies and DM halos, the properties of the MW system, and the disruption of subhalos by the MW disk. Our results are consistent with the cold, collisionless DM paradigm and yield the strongest cosmological constraints to date on particle models of warm, interacting, and fuzzy dark matter. Read More

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Determinants of attitude and intention towards private health insurance: a comparison of insured and uninsured young adults in Australia.

BMC Health Serv Res 2021 Mar 19;21(1):246. Epub 2021 Mar 19.

QUT Business School, Queensland University of Technology, 2 George Street, Brisbane, QLD, 4000, Australia.

Background: Since the introduction in 1984 of Australia's publicly-funded universal healthcare system, Medicare, healthcare financing has relied on a mix of public and private sources to meet the needs of the population (Sowa et al., Appl Health Econ Health Policy 15:31-41, 2018). However, in recent years, there has been a decline in the number of Australians choosing to purchase private health insurance (PHI), particularly within the young adult age group with the proportion of insurance customers aged 20 to 29 falling from 10. Read More

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Evaluation of State Cannabis Laws and Rates of Self-harm and Assault.

JAMA Netw Open 2021 Mar 1;4(3):e211955. Epub 2021 Mar 1.

Center for Innovation to Implementation, Veterans Affairs Palo Alto Health Care System, Palo Alto, California.

Importance: State cannabis laws are changing rapidly. Research is inconclusive about their association with rates of self-harm and assault. Existing studies have not considered variations in cannabis commercialization across states over time. Read More

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An implantable optogenetic stimulator wirelessly powered by flexible photovoltaics with near-infrared (NIR) light.

Biosens Bioelectron 2021 May 4;180:113139. Epub 2021 Mar 4.

School of Mechanical Engineering, Gwangju Institute of Science and Technology (GIST), 123 Cheomdangwagi-ro, Buk-gu, Gwangju, 61005, Republic of Korea. Electronic address:

Optogenetics is a cutting-edge tool in neuroscience that employs light-sensitive proteins and controlled illumination for neuromodulation. Its main advantage is the ability to demonstrate causal relationships by manipulating the activity of specific neuronal populations and observing behavioral phenotypes. However, the tethering system used to deliver light to optogenetic tools can constrain both natural animal behaviors and experimental design. Read More

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Fundus motion during mfERG testing.

Doc Ophthalmol 2021 Mar 13. Epub 2021 Mar 13.

University of Houston College of Optometry, Houston, TX, USA.

Purpose: The purpose of this study was to assess eye movements during a multifocal ERG (mfERG) recording. This study evaluated the relationship between bivariate contour ellipse areas (BCEAs), mfERG amplitudes (Amps) and mfERG implicit times (ITs) with repeat testing and experienced subjects.

Methods: Thirty subjects were selected (15 experienced to ocular procedures and 15 novices). Read More

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The Combined Effect of Haplodiplonty and Partial Clonality on Genotypic and Genetic Diversity in a Finite Mutating Population.

J Hered 2021 Mar;112(1):78-91

Department of Biology, University of Alabama at Birmingham, Birmingham, AL 35294.

Partial clonality is known to affect the genetic composition and evolutionary trajectory of diplontic (single, free-living diploid stage) populations. However, many partially clonal eukaryotes exhibit life cycles in which somatic development occurs in both haploid and diploid individuals (haplodiplontic life cycles). Here, we studied how haplodiplontic life cycles and partial clonality structurally constrain, as immutable parameters, the reshuffling of genetic diversity and its dynamics in populations over generations. Read More

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Functional impact of cancer-associated cohesin variants on gene expression and cellular identity.

Genetics 2021 Apr;217(4)

Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.

Cohesin is a ring-shaped protein complex that controls dynamic chromosome structure. Cohesin activity is important for a variety of biological processes, including formation of DNA loops that regulate gene expression. The precise mechanisms by which cohesin shapes local chromosome structure and gene expression are not fully understood. Read More

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Steady state evoked potential (SSEP) responses in the primary and secondary somatosensory cortices of anesthetized cats: Nonlinearity characterized by harmonic and intermodulation frequencies.

PLoS One 2021 9;16(3):e0240147. Epub 2021 Mar 9.

Turner Institute for Brain and Mental Health, School of Psychological Science, Monash University, Melbourne, Victoria, Australia.

When presented with an oscillatory sensory input at a particular frequency, F [Hz], neural systems respond with the corresponding frequency, f [Hz], and its multiples. When the input includes two frequencies (F1 and F2) and they are nonlinearly integrated in the system, responses at intermodulation frequencies (i.e. Read More

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MicroRNA-221 and -222 modulate intestinal inflammatory Th17 cell response as negative feedback regulators downstream of interleukin-23.

Immunity 2021 Mar 2;54(3):514-525.e6. Epub 2021 Mar 2.

Molecular Immunology and Inflammation Branch, National Institute of Arthritis and Musculoskeletal and Skin Diseases, National Institutes of Health, Bethesda, MD 20892, USA. Electronic address:

MicroRNAs are important regulators of immune responses. Here, we show miR-221 and miR-222 modulate the intestinal Th17 cell response. Expression of miR-221 and miR-222 was induced by proinflammatory cytokines and repressed by the cytokine TGF-β. Read More

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Noise-driven multistability vs deterministic chaos in phenomenological semi-empirical models of whole-brain activity.

Chaos 2021 Feb;31(2):023127

Buenos Aires Physics Institute and Physics Department, University of Buenos Aires, Buenos Aires 1428, Argentina.

An outstanding open problem in neuroscience is to understand how neural systems are capable of producing and sustaining complex spatiotemporal dynamics. Computational models that combine local dynamics with in vivo measurements of anatomical and functional connectivity can be used to test potential mechanisms underlying this complexity. We compared two conceptually different mechanisms: noise-driven switching between equilibrium solutions (modeled by coupled Stuart-Landau oscillators) and deterministic chaos (modeled by coupled Rossler oscillators). Read More

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February 2021

DNA stability: a central design consideration for DNA data storage systems.

Nat Commun 2021 03 1;12(1):1358. Epub 2021 Mar 1.

Department of Chemical and Biomolecular Engineering, North Carolina State University, Raleigh, NC, USA.

Data storage in DNA is a rapidly evolving technology that could be a transformative solution for the rising energy, materials, and space needs of modern information storage. Given that the information medium is DNA itself, its stability under different storage and processing conditions will fundamentally impact and constrain design considerations and data system capabilities. Here we analyze the storage conditions, molecular mechanisms, and stabilization strategies influencing DNA stability and pose specific design configurations and scenarios for future systems that best leverage the considerable advantages of DNA storage. Read More

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Transmission of SARS-CoV-2 in domestic cats imposes a narrow bottleneck.

PLoS Pathog 2021 02 26;17(2):e1009373. Epub 2021 Feb 26.

Department of Pathobiological Sciences, University of Wisconsin-Madison, Madison, Wisconsin, United States of America.

The evolutionary mechanisms by which SARS-CoV-2 viruses adapt to mammalian hosts and, potentially, undergo antigenic evolution depend on the ways genetic variation is generated and selected within and between individual hosts. Using domestic cats as a model, we show that SARS-CoV-2 consensus sequences remain largely unchanged over time within hosts, while dynamic sub-consensus diversity reveals processes of genetic drift and weak purifying selection. We further identify a notable variant at amino acid position 655 in Spike (H655Y), which was previously shown to confer escape from human monoclonal antibodies. Read More

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February 2021

I and Cm in meteorites constrain the last astrophysical source of solar r-process elements.

Science 2021 02;371(6532):945-948

Research Centre for Astronomy and Earth Sciences, Eötvös Loránd Research Network, Konkoly Observatory, 1121 Budapest, Hungary.

The composition of the early Solar System can be inferred from meteorites. Many elements heavier than iron were formed by the rapid neutron capture process (r-process), but the astrophysical sources where this occurred remain poorly understood. We demonstrate that the near-identical half-lives [Formula: see text] of the radioactive r-process nuclei iodine-129 and curium-247 preserve their ratio, irrespective of the time between production and incorporation into the Solar System. Read More

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February 2021

A multi-scale brain map derived from whole-brain volumetric reconstructions.

Nature 2021 03 24;591(7848):105-110. Epub 2021 Feb 24.

School of Computing, University of Leeds, Leeds, UK.

Animal nervous system organization is crucial for all body functions and its disruption can lead to severe cognitive and behavioural impairment. This organization relies on features across scales-from the localization of synapses at the nanoscale, through neurons, which possess intricate neuronal morphologies that underpin circuit organization, to stereotyped connections between different regions of the brain. The sheer complexity of this organ means that the feat of reconstructing and modelling the structure of a complete nervous system that is integrated across all of these scales has yet to be achieved. Read More

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Identifying global favourable habitat for early juvenile loggerhead sea turtles.

J R Soc Interface 2021 02 24;18(175):20200799. Epub 2021 Feb 24.

National Center for Atmospheric Research, Boulder, CO 80305, USA.

Loggerhead sea turtles () nest globally on sandy beaches, with hatchlings dispersing into the open ocean. Where these juveniles go and what habitat they rely on remains a critical research question for informing conservation priorities. Here a high-resolution Earth system model is used to determine the biophysical geography of favourable ocean habitat for loggerhead sea turtles globally during their first year of life on the basis of ocean current transport, thermal constraints and food availability (defined here as the summed lower trophic level carbon biomass). Read More

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February 2021

Developmental processes in Ediacara macrofossils.

Proc Biol Sci 2021 Feb 24;288(1945):20203055. Epub 2021 Feb 24.

Department of Paleobiology MRC-121, National Museum of Natural History, Washington, DC 20013-7012, USA.

The Ediacara Biota preserves the oldest fossil evidence of abundant, complex metazoans. Despite their significance, assigning individual taxa to specific phylogenetic groups has proved problematic. To better understand these forms, we identify developmentally controlled characters in representative taxa from the Ediacaran White Sea assemblage and compare them with the regulatory tools underlying similar traits in modern organisms. Read More

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February 2021

Photosynthetic sensitivity to historic meteorological variability for conifers in the eastern Sierra Nevada.

Int J Biometeorol 2021 Feb 18. Epub 2021 Feb 18.

Department of Environmental Studies, University of California, 1156 High Street, Santa Cruz, CA, 95064, USA.

Increased climatic variability can impact tree physiological processes beyond what is predicted from changes in mean conditions. We assessed the sensitivity of conifer saplings to spatial and temporal variability in meteorological conditions, taking advantage of the end of California's historic drought and the exceedingly wet winter of 2017. We sought to understand how very dry and very wet conditions constrain photosynthesis and growth in four regionally dominant conifers and whether sensitivity in these processes changes across a 500 m gradient in elevation. Read More

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February 2021

Characteristics of global naturopathic education, regulation, and practice frameworks: results from an international survey.

BMC Complement Med Ther 2021 Feb 18;21(1):67. Epub 2021 Feb 18.

Australian Research Centre in Complementary & Integrative Medicine (ARCCIM), School of Public Health, University of Technology Sydney, 15 Broadway, Ultimo, NSW, 2007, Australia.

Background: This descriptive study provides the first examination of global naturopathic education, regulation and practice frameworks that have potential to constrain or assist professional formation and integration in global health systems. Despite increasing public use, a significant workforce, and World Health Organization calls for national policy development to support integration of services, existent frameworks as potential barriers to integration have not been examined.

Methods: This cross-sectional survey utilized purposive sampling of 65 naturopathic organisations (educational institutions, professional associations, and regulatory bodies) from 29 countries. Read More

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February 2021

Development of a new Aerosol Barrier Mask for mitigation of spread of SARS-CoV-2 and other infectious pathogens.

medRxiv 2021 Feb 12. Epub 2021 Feb 12.

Center for Bioelectronics and Biosensors, Biodesign Institute, Arizona State University, Tempe, 85281, Arizona, USA.

The COVID-19 pandemic has caused huge impact on public health and significantly changed our lifestyle. This is due to the fast airborne oro-nasal transmission of SARS-CoV-2 from the infected individuals. The generation of liquid aerosolized particles occurs when the COVID-19 patients speak, sing, cough, sneeze, or simply breathe. Read More

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February 2021

Climate control on terrestrial biospheric carbon turnover.

Proc Natl Acad Sci U S A 2021 Feb;118(8)

Frontiers Science Center for Deep Ocean Multispheres and Earth System, Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University China, Qingdao 266100, China.

Terrestrial vegetation and soils hold three times more carbon than the atmosphere. Much debate concerns how anthropogenic activity will perturb these surface reservoirs, potentially exacerbating ongoing changes to the climate system. Uncertainties specifically persist in extrapolating point-source observations to ecosystem-scale budgets and fluxes, which require consideration of vertical and lateral processes on multiple temporal and spatial scales. Read More

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February 2021