154 results on '"Ben, Davis"'
Search Results
2. Beware the Bounce: Tax-Loss Harvesting during a Stock Market Crash
- Author
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Ben Davis, Tianchuan Li, and Vassilii Nemtchinov
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Strategy and Management ,Business and International Management ,Finance - Published
- 2022
3. Effects of AC frequency on the capacitance measurement of hybrid response pressure sensors
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Zhengjie Li, Kyoung-Ho Ha, Zheliang Wang, Sangjun Kim, Ben Davis, Ruojun Lu, Jayant Sirohi, and Nanshu Lu
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General Chemistry ,Condensed Matter Physics - Abstract
E-skins consisting of soft pressure sensors are enabling technology for soft robots, bio-integrated devices, and deformable touch panels. A well-known bottleneck of capacitive pressure sensors (CPS) is the drastic decay in sensitivity with increasing pressure. To overcome this challenge, we have invented a hybrid-response pressure sensor (HRPS) that exhibits both the piezoresistive and piezocapacitive effects intrinsic to a highly porous nanocomposite (PNC) with carbon nanotube (CNT) dopants. The HRPS is constructed with two conductive electrodes sandwiching a laminated PNC and a stiff dielectric layer. We have simplified the hybrid response into a parallel resistor-capacitor circuit, whose output depends on the AC (alternating current) frequency used for the capacitance measurement. Herein, through theoretical analysis, we discover a dimensionless parameter that governs the frequency responses of the HRPS. The master curve is validated through experiments on the HRPS with various doping ratios, subject to different compressive strains, under diverse AC frequencies. In addition, the relative contribution of piezoresistive and piezocapacitive mechanisms are also found to vary with the three parameters. Based on this experimentally validated theory, we establish a very practical guideline for selecting the optimal AC frequency for the capacitance measurement of HRPSs.
- Published
- 2022
4. A re-examination of the mechanism of whiting events: a new role for diatoms in Fayetteville Green Lake (New York, USA)
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Chloe Stanton, Ben Davis Barnes, Lee R. Kump, and Julie Cosmidis
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General Earth and Planetary Sciences ,Ecology, Evolution, Behavior and Systematics ,General Environmental Science - Abstract
Whiting events-the episodic precipitation of fine-grained suspended calcium carbonates in the water column-have been documented across a variety of marine and lacustrine environments. Whitings likely are a major source of carbonate muds, a constituent of limestones, and important archives for geochemical proxies of Earth history. While several biological and physical mechanisms have been proposed to explain the onset of these precipitation events, no consensus has been reached thus far. Fayetteville Green Lake (New York, USA) is a meromictic lake that experiences annual whitings. Materials suspended in the water column collected through the whiting season were characterized using scanning electron microscopy and scanning transmission X-ray microscopy. Whitings in Fayetteville Green Lake are initiated in the spring within the top few meters of the water column, by precipitation of fine amorphous calcium carbonate (ACC) phases nucleating on microbial cells, as well as on abundant extracellular polymeric substances (EPS) frequently associated with centric diatoms. Whiting particles found in the summer consist of 5-7 μm calcite grains forming aggregates with diatoms and EPS. Simple calculations demonstrate that calcite particles continuously grow over several days, then sink quickly through the water column. In the late summer, partial calcium carbonate dissolution is observed deeper in the water column. Settling whiting particles, however, reach the bottom of the lake, where they form a major constituent of the sediment, along with diatom frustules. The role of diatoms and associated EPS acting as nucleation surfaces for calcium carbonates is described for the first time here as a potential mechanism participating in whitings at Fayetteville Green Lake. This mechanism may have been largely overlooked in other whiting events in modern and ancient environments.
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- 2023
5. Aboriginal young people’s perspectives and experiences of accessing sexual health services and sex education in Australia: A qualitative study
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Simon Graham, Kacey Martin, Kristy Gardner, Mitchell Beadman, Michael F. Doyle, Reuben Bolt, Dean Murphy, Christy E. Newman, Stephen Bell, Carla Treloar, Annette J. Browne, Peter Aggleton, Karen Beetson, Megan Brooks, Jessica R. Botfield, Ben Davis, Jessica Wilms, Bronwyn Leece, Linda Stanbury, and Joanne Bryant
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Public Health, Environmental and Occupational Health - Published
- 2023
6. A model for estimating costs and benefits of new vaccine technologies from the perspective of both buyers and sellers
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Michael Krautmann, Ben Davis, and Pascale R. Leroueil
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Multidisciplinary - Abstract
Although vaccination is widely considered one of the most cost-effective health interventions available, global coverage rates for many vaccines remain lower than necessary for disease elimination and eradication. New vaccine technologies can play an important role in addressing barriers to vaccination and increasing coverage rates. To identify and prioritize vaccine technology investments, decision makers must be able to compare the overall costs and benefits of each investment option. While these data points may exist, they are often confined to silos. Decision makers would benefit from a model that synthesizes this broad range of data and provides clear and actionable information. To facilitate vaccine investment, purchasing and deployment decisions, we developed a systematic and transparent cost-benefit model that estimates the value and risk of a given investment scenario from the perspective of both “buyers” (e.g., global donors, country governments) and “sellers” (e.g., developers, manufacturers) of vaccines. This model, which can be used to evaluate scenarios related to a single vaccine presentation or a portfolio of vaccine presentations, leverages our published approach for estimating the impact of improved vaccine technologies on vaccination coverage rates. This article presents a description of the model and provides an illustrative example application to a portfolio of measles-rubella vaccine technologies currently under development. Although the model is generally applicable to organizations involved in vaccine investment, manufacturing or purchasing, we believe it may be particularly useful to those engaged in vaccine markets that rely strongly on funding from institutional donors.
- Published
- 2023
7. Sulfur cycling at natural hydrocarbon and sulfur seeps in Santa Paula Creek, CA
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Heidi S, Aronson, Danielle R, Monteverde, Ben Davis, Barnes, Brooke R, Johnson, Mike J, Zawaski, Daan R, Speth, Xingchen Tony, Wang, Fenfang, Wu, Samuel M, Webb, Elizabeth J, Trower, John S, Magyar, Alex L, Sessions, Victoria J, Orphan, and Woodward W, Fischer
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Microbiota ,RNA, Ribosomal, 16S ,General Earth and Planetary Sciences ,Sulfides ,Ecology, Evolution, Behavior and Systematics ,California ,Hydrocarbons ,Phylogeny ,Sulfur ,General Environmental Science - Abstract
Biogeochemical cycling of sulfur is relatively understudied in terrestrial environments compared to marine environments. However, the comparative ease of access, observation, and sampling of terrestrial settings can expand our understanding of organisms and processes important in the modern sulfur cycle. Furthermore, these sites may allow for the discovery of useful process analogs for ancient sulfur-metabolizing microbial communities at times in Earth's past when atmospheric O2 concentrations were lower and sulfide was more prevalent in Earth surface environments. We identified a new site at Santa Paula Creek (SPC) in Ventura County, CA—a remarkable freshwater, gravel-bedded mountain stream charged with a range of oxidized and reduced sulfur species and heavy hydrocarbons from the emergence of subsurface fluids within the underlying sulfur- and organic-rich Miocene-age Monterey Formation. SPC hosts a suite of morphologically distinct microbial biofacies that form in association with the naturally occurring hydrocarbon seeps and sulfur springs. We characterized the geology, stream geochemistry, and microbial facies and diversity of the Santa Paula Creek ecosystem. Using geochemical analyses and 16S rRNA gene sequencing, we found that SPC supports a dynamic sulfur cycle that is largely driven by sulfide-oxidizing microbial taxa, with contributions from smaller populations of sulfate-reducing and sulfur-disproportionating taxa. This preliminary characterization of SPC revealed an intriguing site in which to study geological and geochemical controls on microbial community composition and to expand our understanding of sulfur cycling in terrestrial environments.
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- 2022
8. Authigenic carbonate burial in the Late Devonian–Early Mississippian Bakken Formation (Williston Basin, <scp>USA</scp> )
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Jon M. Husson, Shanan E. Peters, and Ben Davis Barnes
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chemistry.chemical_compound ,chemistry ,Stratigraphy ,Geochemistry ,Carbonate ,Geology ,Late Devonian extinction ,Authigenic ,Structural basin ,Devonian - Published
- 2020
9. Fragment‐Based Ligand Discovery
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Ben Davis and Roderick E. Hubbard
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Chemistry ,Stereochemistry ,Fragment (computer graphics) ,Ligand (biochemistry) - Published
- 2020
10. Inverse calculation of cross-spectral densities using a Bayesian inference approach
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Ben Davis, Garret Lopp, and Ryan Schultz
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- 2022
11. A covalent strategy to target intrinsically disordered proteins: Discovery of novel tau aggregation inhibitors
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László Petri, Péter Ábrányi-Balogh, Darius Vagrys, Tímea Imre, Nikolett Varró, István Mándity, Anita Rácz, Lucia Wittner, Kinga Tóth, Estilla Zsófia Tóth, Tünde Juhász, Ben Davis, and György Miklós Keserű
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Pharmacology ,Intrinsically Disordered Proteins ,Tauopathies ,Drug Design ,Organic Chemistry ,Drug Discovery ,Humans ,Neurodegenerative Diseases ,tau Proteins ,General Medicine ,Cysteine - Abstract
Intrinsically disordered proteins (IDPs) play important roles in disease pathologies; however, their lack of defined stable 3D structures make traditional drug design strategies typically less effective against these targets. Based on promising results of targeted covalent inhibitors (TCIs) on challenging targets, we have developed a covalent design strategy targeting IDPs. As a model system we chose tau, an endogenous IDP of the central nervous system that is associated with severe neurodegenerative diseases via its aggregation. First, we mapped the tractability of available cysteines in tau and prioritized suitable warheads. Next, we introduced the selected vinylsulfone warhead to the non-covalent scaffolds of potential tau aggregation inhibitors. The designed covalent tau binders were synthesized and tested in aggregation models, and inhibited tau aggregation effectively. Our results revealed the usefulness of the covalent design strategy against therapeutically relevant IDP targets and provided promising candidates for the treatment of tauopathies.
- Published
- 2021
12. On public-coin zero-error randomized communication complexity
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Ben Davis, Hamed Hatami, William Pires, Ran Tao, and Hamza Usmani
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Signal Processing ,Computer Science Applications ,Information Systems ,Theoretical Computer Science - Published
- 2022
13. A method for estimating the impact of new vaccine technologies on vaccination coverage rates
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Ben Davis, Michael Krautmann, and Pascale R. Leroueil
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Multidisciplinary ,Vaccination Coverage ,Immunization Programs ,Science ,Data Interpretation, Statistical ,Vaccine Development ,Medicine ,Humans ,Technology, Pharmaceutical ,Mathematics ,Measles-Mumps-Rubella Vaccine ,Biotechnology - Abstract
Vaccines are one of the most cost-effective tools for improving human health and well-being. The impact of a vaccine on population health is partly determined by its coverage rate, the proportion of eligible individuals vaccinated. Coverage rate is a function of the vaccine presentation and the population in which that presentation is deployed. This population includes not only the individuals vaccinated, but also the logistics and healthcare systems responsible for vaccine delivery. Because vaccine coverage rates remain below targets in many settings, vaccine manufacturers and purchasers have a shared interest in better understanding the relationship between vaccine presentation, population characteristics, and coverage rate. While there have been some efforts to describe this relationship, existing research and tools are limited in their ability to quantify coverage rate changes across a broad set of antigens, vaccine presentations, and geographies. In this article, we present a method for estimating the impact of improved vaccine technologies on vaccination coverage rates. It is designed for use with low- and middle-income country vaccination programs. This method uses publicly available data and simple calculations based on probability theory to generate coverage rate values. We first present the conceptual framework and mathematical approach. Using a Microsoft Excel-based implementation, we then apply the method to a vaccine technology in early-stage development: micro-array patch for a measles-rubella vaccine (MR-MAP). Example outputs indicate that a complete switch from the current subcutaneous presentation to MR-MAP in the 73 countries ever eligible for Gavi support would increase overall vaccination coverage by 3.0–4.9 percentage points depending on the final characteristics of the MR-MAP. This change equates to an additional 2.6–4.2 million children vaccinated per year. Our method can be readily extended to other antigens and vaccine technologies to provide quick, low-cost estimates of coverage impact. As vaccine manufacturers and purchasers face increasingly complex decisions, such estimates could facilitate objective comparisons between options and help these decision makers obtain the most value for money.
- Published
- 2021
14. Fragment Screening by NMR
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Ben Davis
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0303 health sciences ,03 medical and health sciences ,Fragment (logic) ,010405 organic chemistry ,Computer science ,Fragment-based lead discovery ,Proton NMR ,Computational biology ,01 natural sciences ,030304 developmental biology ,0104 chemical sciences - Abstract
This chapter describes the use of NMR to screen a fragment library as part of a fragment-based lead discovery (FBLD) campaign. The emphasis is on the practicalities involved in fragment screening by NMR, with particular attention to the use of 1D ligand-observed 1H NMR experiments. An overview of the theoretical considerations underlying the choice of method and experimental configuration is given, along with a discussion of steps that can be taken in order to minimize the risk of experimental artifacts often associated with the identification of low-affinity interactions.
- Published
- 2021
15. Multiplexed experimental strategies for fragment library screening using SPR biosensors
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Ben Davis, Giulia Opassi, Darius Vagrys, U. Helena Danielson, Iwan J. P. de Esch, Anna Moberg, P. Boronat, Roderick E. Hubbard, Doreen Dobritzsch, Claes Holmgren, Jacqueline E. van Muijlwijk-Koezen, David J. Hamilton, Edward A. FitzGerald, Peter O'Brien, Daniela Cederfelt, Hanna F. Klein, Maikel Wijtmans, Vladimir O. Talibov, Mia Abramsson, Maria T. Lindgren, Innovations in Human Health & Life Sciences, AIMMS, Chemistry and Pharmaceutical Sciences, and Medicinal chemistry
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Materials science ,Fragment (computer graphics) ,Nanotechnology ,Surface plasmon resonance biosensor ,Biosensor - Abstract
Surface plasmon resonance biosensor technology (SPR) is ideally suited for fragment-based lead discovery. However, generally suitable experimental procedures or detailed protocols are lacking, especially for structurally or physico-chemically challenging targets or when tool compounds are lacking. Success depends on accounting for the features of both the target and the chemical library, purposely designing screening experiments for identification and validation of hits with desired specificity and mode-of-action, and availability of orthogonal methods capable of confirming fragment hits. By adopting a multiplexed strategy, the range of targets and libraries amenable to an SPR biosensor-based approach for identifying hits is considerably expanded. We here illustrate innovative strategies using five challenging targets and variants thereof. Two libraries of 90 and 1056 fragments were screened using two different flow-based SPR biosensor systems, allowing different experimental approaches. Practical considerations and procedures accounting for the characteristics of the proteins and libraries, and that increase robustness, sensitivity, throughput and versatility are highlighted.
- Published
- 2020
16. Exploring IDP–Ligand Interactions: Tau K18 as a Test Case
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Roderick E. Hubbard, Ben Davis, Darius Vagrys, Chen I-Jen, and James Edward Paul Davidson
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0301 basic medicine ,tau Proteins ,Fluorine-19 NMR ,macromolecular substances ,Intrinsically disordered proteins ,Ligands ,Catalysis ,Article ,Inorganic Chemistry ,lcsh:Chemistry ,03 medical and health sciences ,0302 clinical medicine ,Humans ,Physical and Theoretical Chemistry ,Surface plasmon resonance ,Molecular Biology ,lcsh:QH301-705.5 ,Nuclear Magnetic Resonance, Biomolecular ,Spectroscopy ,Microscale thermophoresis ,Chemistry ,Organic Chemistry ,General Medicine ,Ligand (biochemistry) ,intrinsically disordered protein ,microscale thermophoresis ,Computer Science Applications ,Intrinsically Disordered Proteins ,Molecular Docking Simulation ,nuclear magnetic resonance ,030104 developmental biology ,lcsh:Biology (General) ,lcsh:QD1-999 ,Biophysics ,tau K18 ,030217 neurology & neurosurgery ,surface plasmon resonance - Abstract
Over the past decade intrinsically disordered proteins (IDPs) have emerged as a biologically important class of proteins, many of which are of therapeutic relevance. Here, we investigated the interactions between a model IDP system, tau K18, and nine literature compounds that have been reported as having an effect on tau in order to identify a robust IDP&ndash, ligand system for the optimization of a range of biophysical methods. We used NMR, surface plasmon resonance (SPR) and microscale thermophoresis (MST) methods to investigate the binding of these compounds to tau K18, only one showed unambiguous interaction with tau K18. Several near neighbors of this compound were synthesized and their interactions with tau K18 characterized using additional NMR methods, including 1D ligand-observed NMR, diffusion-ordered spectroscopy (DOSY) and 19F NMR. This study demonstrates that it is possible to detect and characterize IDP&ndash, ligand interactions using biophysical methods. However, care must be taken to account for possible artefacts, particularly the impact of compound solubility and where the protein has to be immobilized.
- Published
- 2020
17. Hemorrhage-Control Training in Medical Education
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Mary K. Kimbrough, Avi Bhavaraju, Anna Privratsky, Ronald D. Robertson, Ben Davis, Hanna K. Jensen, Carol R. Thrush, Jared T Gowen, William C Beck, Kevin W. Sexton, and John R Taylor
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Medical education ,lcsh:LC8-6691 ,lcsh:R5-920 ,lcsh:Special aspects of education ,business.industry ,education ,hemorrhage control ,Stop the Bleed ,030208 emergency & critical care medicine ,B-Con ,Training (civil) ,03 medical and health sciences ,0302 clinical medicine ,Medicine ,Hemorrhage control ,Medical school curriculum ,030212 general & internal medicine ,tourniquet training ,business ,lcsh:Medicine (General) ,medical education ,Original Research - Abstract
Objectives: To evaluate and analyze the efficacy of implementation of hemorrhage-control training into the formal medical school curriculum. We predict this training will increase the comfort and confidence levels of students with controlling major hemorrhage and they will find this a valuable skill set for medical and other healthcare professional students. Methods: After IRB and institutional approval was obtained, hemorrhage-control education was incorporated into the surgery clerkship curriculum for 96 third-year medical students at the University of Arkansas for Medical Sciences using the national Stop The Bleed program. Using a prospective study design, participants completed pre- and post-training surveys to gauge prior experiences and comfort levels with controlling hemorrhage and confidence levels with the techniques taught. Course participation was mandatory; survey completion was optional. The investigators were blinded as to the individual student’s survey responses. A knowledge quiz was completed following the training. Results: Implementation of STB training resulted in a significant increase in comfort and confidence among students with all hemorrhage-control techniques. There was also a significant difference in students’ perceptions of the importance of this training for physicians and other allied health professionals. Conclusion: Hemorrhage-control training can be effectively incorporated into the formal medical school curriculum via a single 2-hour Stop The Bleed course, increasing students’ comfort level and confidence with controlling major traumatic bleeding. Students value this training and feel it is a beneficial addition to their education. We believe this should be a standard part of undergraduate medical education.
- Published
- 2020
18. Protein-fragment complex structures derived by NMR molecular replacement
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Julien Orts, Celestine N. Chi, Dean Strotz, Dhiman Ghosh, Ben Davis, and Felix Torres
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0301 basic medicine ,genetic structures ,Stereochemistry ,Pharmaceutical Science ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Weak binding ,03 medical and health sciences ,Fragment (logic) ,Drug Discovery ,Molecular replacement ,Pharmacology ,Chemistry ,Ligand ,Organic Chemistry ,fungi ,Interaction site ,food and beverages ,Affinities ,Small molecule ,0104 chemical sciences ,030104 developmental biology ,Protein Fragment ,Molecular Medicine - Abstract
The NMR2 method can derive protein–fragment structures with a cooperative assignment strategy, opening an avenue for NMR-based fragment lead discovery., Recently we have established an NMR molecular replacement method, which is capable of solving the structure of the interaction site of protein–ligand complexes in a fully automated manner. While the method was successfully applied for ligands with strong and weak binding affinities, including small molecules and peptides, its applicability on ligand fragments remains to be shown. Structures of fragment–protein complexes are more challenging for the method since fragments contain only few protons. Here we show a successful application of the NMR molecular replacement method in solving structures of complexes between three derivatives of a ligand fragment and the protein receptor PIN1. We anticipate that this approach will find a broad application in fragment-based lead discovery.
- Published
- 2020
19. The Secular Evolution of the Reverse Weathering Sink in the Global Li Cycle
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Matthew Fantle, Ben Davis Barnes, and Elizabeth Andrews
- Published
- 2020
20. The Role of Seafloor-Hydrothermal Activity as a Driver of Marine Anoxia
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Ben Davis Barnes, John Slack, Mark Hannington, Noah Planavsky, and Lee Kump
- Published
- 2020
21. Tailings and tracings: using art and social science to explore the limits of visual methods at mining and industrial ruins
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Kevin Walby and Ben Davis
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Visual Arts and Performing Arts ,Communication - Abstract
This article examines a novel approach to visual methods that artist Ben Davis has developed based on sociologist Kevin Walby’s research into decommissioned industrial sites, which is referred to here as tracing. Disrupting the over-reliance on photographic representation in visual methods in the social sciences, the authors integrate audio recordings of interviews, as well as photos, maps, and building plans for pop-up mining communities into visual art works to provide a counter-visual analysis of the landscapes depicted in Kevin Walby’s photographs of Uranium City. After reviewing literature on environmental degradation and on visual methods, the article elaborates on Ben Davis’s practice of tracing as a technique representing the feeling of decomposition and decay generated by the harms of industrial resource extraction. The authors argue that the technique of tracing excavates layered histories of place, providing a way of creating new interpretations of social and environmental issues. They then discuss how this counter-visual analysis and approach to tracing enables a trans-disciplinary and dialogical space for engagement with academics, artists, and activists to explore issues centered on land, contamination, and justice.
- Published
- 2022
22. Cronobacter spp.—Opportunistic Foodborne Pathogens: an Update on Evolution, Osmotic Adaptation and Pathogenesis
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Séamus Fanning, Ben Davis Tall, Shabarinath Srikumar, Angelika Lehner, University of Zurich, and Lehner, Angelika
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0301 basic medicine ,Microbiology (medical) ,Genetics ,biology ,In silico ,030106 microbiology ,610 Medicine & health ,2725 Infectious Diseases ,Proteomics ,biology.organism_classification ,Genome ,2726 Microbiology (medical) ,DNA sequencing ,03 medical and health sciences ,030104 developmental biology ,Infectious Diseases ,570 Life sciences ,Adaptation ,Cronobacter ,Niche adaptation ,Gene ,10082 Institute of Food Safety and Hygiene - Abstract
Cronobacter spp. are opportunistic, foodborne pathogens capable of causing severe illnesses predominantly in premature and low-birth-weight infants. These organisms have evolved features, which aid them to survive under harsh environmental conditions but may also contribute to pathogenesis during infection. In this review, we highlight efforts to study genetic diversity and evolutionary aspects, osmotic adaptation and pathogenesis of these pathogens. Next-generation genome sequencing-based techniques elucidated a species-level bidirectional divergence driven by niche adaptation in Cronobacter spp. Whole genome comparisons and proteomics revealed genes and pathways contributing to the survival and persistence phenotype in low-moisture environments. In silico genome comparisons and application of suitable in vivo models provided answers to pathogenesis-related questions. Development and application of innovative molecular techniques and in vivo infection models have shed light on how Cronobacter spp. adapt to challenges experienced in natural, food processing and host-related environments.
- Published
- 2018
23. Predictability of what or where reduces brain activity, but a bottleneck occurs when both are predictable
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Ben Davis and Uri Hasson
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Adult ,Male ,Predictive coding ,PREDICTION ,Brain activity and meditation ,Disorder ,Entropy ,Uncertainty ,statistical learning ,Cognitive Neuroscience ,Thalamus ,Sensory system ,050105 experimental psychology ,Bottleneck ,Executive Function ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,medicine ,Humans ,0501 psychology and cognitive sciences ,Anterior cingulate cortex ,Cerebral Cortex ,Temporal cortex ,Communication ,business.industry ,Functional Neuroimaging ,Putamen ,05 social sciences ,Anticipation, Psychological ,Magnetic Resonance Imaging ,Semantics ,Neostriatum ,medicine.anatomical_structure ,Visual cortex ,Pattern Recognition, Visual ,Neurology ,Space Perception ,Female ,Psychology ,business ,Neuroscience ,Psychomotor Performance ,030217 neurology & neurosurgery - Abstract
Detecting regularities in the sensory environment licenses predictions that enable adaptive behaviour. However, it is unclear whether predictions about object category, location, or both dimensions are mediated by overlapping systems, and relatedly, whether constructing predictions about both category and location is associated with processing bottlenecks. To examine this issue, in an fMRI study, we presented participants with image-series in which non-deterministic transition probabilities enabled predictions about either the location of the next image, its semantic category, both dimensions, or neither (the latter forming a “no-regularity” random baseline condition). Speaking to a common system, all three predictable conditions resulted in reduced BOLD activity in four clusters: left rostral anterior cingulate cortex; bilateral putamen, caudate and thalamus; right precentral gyrus, and left visual cortex. Pointing to a processing bottleneck, in some regions, a significant interaction between the two factors was found whereby category-predictable series were associated with lower activity – but only when location regularity was absent. Finally, category regularity decreased activation in areas of the ventral visual stream and semantic areas of lateral temporal cortex, and location regularity decreased activation in a dorsal fronto-parietal cluster, long implicated in the endogenous control of spatial attention. Our findings confirm and expand a role for dACC/dmPFC and striatum in monitoring or responding to uncertainty in the environment and point to a limited capacity bottleneck when multiple predictions are concurrently licensed.
- Published
- 2018
24. Comments on ‘Increased catches of snow crab (Chionoecetes opilio) with luminescent-netting pots at long soak times by Nguyen et al. 2020’
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Katherine R. Skanes, Ben Davis, Darrell R.J. Mullowney, Derek Osborne, Julia R. Pantin, William A. Coffey, Sanaollah Zabihi-Seissan, Krista D. Baker, and Elizabeth Coughlan
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Fishery ,biology ,Chionoecetes opilio ,Environmental science ,Aquatic Science ,Netting ,biology.organism_classification ,Snow - Published
- 2021
25. Visual cortex signals a mismatch between regularity of auditory and visual streams
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Ben Davis, Uri Hasson, and Michael Andric
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Adult ,Male ,Time Factors ,genetic structures ,Cognitive Neuroscience ,050105 experimental psychology ,lcsh:RC321-571 ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Stimulus modality ,Cortex (anatomy) ,Neurology ,medicine ,Humans ,0501 psychology and cognitive sciences ,Computer vision ,Cerebrum ,lcsh:Neurosciences. Biological psychiatry. Neuropsychiatry ,Visual Cortex ,Brain Mapping ,business.industry ,05 social sciences ,Cognition ,Magnetic Resonance Imaging ,Visual cortex ,medicine.anatomical_structure ,Auditory Perception ,Visual Perception ,Female ,Artificial intelligence ,Psychology ,business ,Neuroscience ,030217 neurology & neurosurgery - Abstract
Understanding how humans code for and respond to environmental uncertainty/regularity is a question shared by current computational and neurobiological approaches to human cognition. To date, studies investigating neurobiological systems that track input uncertainty have examined responses to uni-sensory streams. It is not known, however, whether there exist brain systems that combine information about the regularity of input streams presented to different senses. We report an fMRI study that aimed to identify brain systems that relate statistical information across sensory modalities. We constructed temporally extended auditory and visual streams, each of which could be random or highly regular, and presented them concurrently. We found strong signatures of “regularity matching” in visual cortex bilaterally; responses were higher when the level of regularity in the auditory and visual streams mismatched than when it matched, [(AudHigh/VisLow and AudLow/VisHigh) >(AudLow/VisLow and AudHigh/VisHigh)]. In addition, several frontal and parietal regions tracked regularity of the auditory or visual stream independently of the other stream's regularity. An individual-differences analysis suggested that signatures of single-modality-focused regularity tracking in these fronto-parietal regions are inversely related to signatures of regularity-matching in visual cortex. Our findings suggest that i) visual cortex is a junction for integration of temporally-extended auditory and visual inputs and that ii) multisensory regularity-matching depends on balanced processing of both input modalities. We discuss the implications of these findings for neurobiological models of uncertainty and for understanding computations that underlie multisensory interactions in occipital cortex.
- Published
- 2017
26. Two-dimensional NMR lineshape analysis of single, multiple, zero and double quantum correlation experiments
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Margaux Ouvry, Christopher A. Waudby, Ben Davis, and John Christodoulou
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0301 basic medicine ,Materials science ,Two-dimensional NMR ,Chemical exchange ,Ligands ,010402 general chemistry ,01 natural sciences ,Biochemistry ,Article ,Spectral line ,03 medical and health sciences ,Protein Domains ,Zero-quantum ,HSP90 Heat-Shock Proteins ,Sensitivity (control systems) ,Nuclear Magnetic Resonance, Biomolecular ,Spectroscopy ,030304 developmental biology ,0303 health sciences ,Double-quantum ,Series (mathematics) ,Chemistry ,Relaxation (NMR) ,Nuclear magnetic resonance spectroscopy ,0104 chemical sciences ,Dissociation constant ,NMR spectra database ,030104 developmental biology ,Chemical physics ,Titrations ,Quantum Theory ,Multiple-quantum ,Lineshape analysis ,Algorithms ,Heteronuclear single quantum coherence spectroscopy ,Protein Binding - Abstract
NMR spectroscopy provides a powerful approach for the characterisation of chemical exchange and molecular interactions by analysis of series of experiments acquired over the course of a titration measurement. The appearance of NMR resonances undergoing chemical exchange depends on the frequency difference relative to the rate of exchange, and in the case of one-dimensional experiments chemical exchange regimes are well established and well known. However, two-dimensional experiments present additional complexity, as at least one additional frequency difference must be considered. Here we provide a systematic classification of chemical exchange regimes in two-dimensional NMR spectra. We highlight important differences between exchange in HSQC and HMQC experiments, that on a practical level result in more severe exchange broadening in HMQC spectra, but show that complementary alternatives to the HMQC are available in the form of HZQC and HDQC experiments. We present the longitudinal relaxation optimised SOFAST-H(Z/D)QC experiment for the simultaneous acquisition of sensitivity-enhanced HZQC and HDQC spectra, and the longitudinal and transverse relaxation optimised BEST-ZQ-TROSY for analysis of large molecular weight systems. We describe the application of these experiments to the characterisation of the interaction between the Hsp90 N-terminal domain and a small molecule ligand, and show that the independent analysis of HSQC, HMQC, HZQC and HDQC experiments provides improved confidence in the fitted dissociation constant and dissociation rate. Joint analysis of such data may provide improved sensitivity to detect and analyse more complex multi-state interaction mechanisms such as induced fit or conformational selection. Electronic supplementary material The online version of this article (10.1007/s10858-019-00297-7) contains supplementary material, which is available to authorized users.
- Published
- 2019
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27. Structure-Guided Discovery of a Selective Mcl-1 Inhibitor with Cellular Activity
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Didier Demarles, James Edward Paul Davidson, Levente Ondi, Allan E. Surgenor, Frédéric Colland, Attila Paczal, Marion Zarka, Alan P. Robertson, Zoltán B. Szabó, András Kotschy, Julia Smith, Perron-Sierra Françoise, Gabor Radics, Audrey Claperon, Ben Davis, Pawel Dokurno, Szlávik Zoltán, Csékei Márton, Gaetane LeToumelin-Braizat, Roderick E. Hubbard, Chen I-Jen, C. Pedder, Olivier Geneste, James Murray, and Nicolas Cauquil
- Subjects
Cell Survival ,Cell ,Thiophenes ,01 natural sciences ,03 medical and health sciences ,chemistry.chemical_compound ,Structure-Activity Relationship ,Downregulation and upregulation ,Drug Discovery ,medicine ,Humans ,Caspase ,030304 developmental biology ,chemistry.chemical_classification ,0303 health sciences ,biology ,Drug discovery ,HCT116 Cells ,Small molecule ,0104 chemical sciences ,Amino acid ,Protein Structure, Tertiary ,010404 medicinal & biomolecular chemistry ,medicine.anatomical_structure ,Pyrimidines ,chemistry ,biology.protein ,Cancer research ,Molecular Medicine ,Myeloid Cell Leukemia Sequence 1 Protein ,Growth inhibition ,Lead compound ,HeLa Cells - Abstract
Myeloid cell leukemia 1 (Mcl-1), an antiapoptotic member of the Bcl-2 family of proteins, whose upregulation when observed in human cancers is associated with high tumor grade, poor survival, and resistance to chemotherapy, has emerged as an attractive target for cancer therapy. Here, we report the discovery of selective small molecule inhibitors of Mcl-1 that inhibit cellular activity. Fragment screening identified thienopyrimidine amino acids as promising but nonselective hits that were optimized using nuclear magnetic resonance and X-ray-derived structural information. The introduction of hindered rotation along a biaryl axis has conferred high selectivity to the compounds, and cellular activity was brought on scale by offsetting the negative charge of the anchoring carboxylate group. The obtained compounds described here exhibit nanomolar binding affinity and mechanism-based cellular efficacy, caspase induction, and growth inhibition. These early research efforts illustrate drug discovery optimization from thienopyrimidine hits to a lead compound, the chemical series leading to the identification of our more advanced compounds S63845 and S64315.
- Published
- 2019
28. Tunneling Back-Contacted Photovoltaics
- Author
-
Nicholas C. Strandwitz and Ben Davis
- Subjects
Materials science ,business.industry ,Photovoltaics ,Optoelectronics ,business ,Quantum tunnelling - Published
- 2019
29. Establishing Drug Discovery and Identification of Hit Series for the Anti-apoptotic Proteins, Bcl-2 and Mcl-1
- Author
-
Pawel Dokurno, R. Harris, Patrick Casara, James Edward Paul Davidson, Olivier Geneste, Julia Smith, Douglas S. Williamson, Natalia Matassova, Yikang Wang, Allan M. Jordan, Stephen D. Roughley, András Kotschy, Roderick E. Hubbard, Jerome Stark, John A. Hickman, Chen I-Jen, Ben Davis, James Brooke Murray, C. Pedder, Walmsley Claire, Thierry Le Diguarher, Neil Whitehead, Stuart C. Ray, and Christopher John Graham
- Subjects
Series (mathematics) ,Chemistry ,Drug discovery ,General Chemical Engineering ,Isothermal titration calorimetry ,General Chemistry ,Computational biology ,Small molecule ,Article ,Anti-Apoptotic Proteins ,lcsh:Chemistry ,Heteronuclear molecule ,lcsh:QD1-999 ,Surface plasmon resonance - Abstract
We describe our work to establish structure- and fragment-based drug discovery to identify small molecules that inhibit the anti-apoptotic activity of the proteins Mcl-1 and Bcl-2. This identified hit series of compounds, some of which were subsequently optimized to clinical candidates in trials for treating various cancers. Many protein constructs were designed to identify protein with suitable properties for different biophysical assays and structural methods. Fragment screening using ligand-observed NMR experiments identified several series of compounds for each protein. The series were assessed for their potential for subsequent optimization using 1H and 15N heteronuclear single-quantum correlation NMR, surface plasmon resonance, and isothermal titration calorimetry measurements to characterize and validate binding. Crystal structures could not be determined for the early hits, so NMR methods were developed to provide models of compound binding to guide compound optimization. For Mcl-1, a benzodioxane/benzoxazine series was optimized to a Kd of 40 μM before a thienopyrimidine hit series was identified which subsequently led to the lead series from which the clinical candidate S 64315 (MIK 665) was identified. For Bcl-2, the fragment-derived series were difficult to progress, and a compound derived from a published tetrahydroquinone compound was taken forward as the hit from which the clinical candidate (S 55746) was obtained. For both the proteins, the work to establish a portfolio of assays gave confidence for identification of compounds suitable for optimization.
- Published
- 2019
30. Willingness to pay for medical treatments in chronic diseases: a multicountry survey of patients and physicians
- Author
-
Joël Ladner, Etienne Audureau, Joseph Saba, Marie Hélène Besson, Ben Davis, Service de santé publique [Mondor], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Henri Mondor-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Axios International France, Nutrition, inflammation et dysfonctionnement de l'axe intestin-cerveau (ADEN), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institute for Research and Innovation in Biomedicine (IRIB), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), UNIROUEN - UFR Santé (UNIROUEN UFR Santé), Normandie Université (NU)-Normandie Université (NU), Département d'épidémiologie et de promotion de la santé [Rouen], CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), and Normandie Université (NU)
- Subjects
Adult ,Male ,medicine.medical_specialty ,Multivariate analysis ,Patients ,Attitude of Health Personnel ,Developing country ,Disease ,Affect (psychology) ,03 medical and health sciences ,0302 clinical medicine ,Willingness to pay ,Pregnancy ,Environmental health ,Physicians ,Surveys and Questionnaires ,Medicine ,Humans ,Psoriasis ,030212 general & internal medicine ,Developing Countries ,ComputingMilieux_MISCELLANEOUS ,Aged ,Heart Failure ,Contingent valuation ,business.industry ,Health Policy ,Public health ,1. No poverty ,Middle Aged ,3. Good health ,Purchasing power parity ,Cross-Sectional Studies ,030220 oncology & carcinogenesis ,Chronic Disease ,Income ,Educational Status ,[SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie ,Female ,Health Expenditures ,business - Abstract
Aim: The objective was to investigate factors influencing patients’ willingness to pay (WTP) and physician’s views on the cost of therapy for two contrasted chronic diseases, chronic heart failure and psoriasis. Methods: A cross-sectional survey was conducted in ten developing countries, using a stated WTP contingent valuation method. Multivariate analyses were performed by linear regression. Results: Independent factors influencing patient WTP were income (+0.04 $PPP [purchasing power parity] in WTP per $PPP in monthly income; p Conclusion: Disease-specific factors may affect WTP for treatment that should be accounted for to support effective public health programs in developing countries.
- Published
- 2019
31. List of Contributors
- Author
-
José Aguilar-Manjarrez, Arwen Bailey, Jennie Barron, Caterina Batello, Lorenzo Giovanni Bellù, Zareen Pervez Bharucha, Kartika Bhatia, Regina Birner, Sally Bunning, Clayton Campanhola, Andrea Cattaneo, Molly Conlin, Valerio Crespi, Ben Davis, Jeroen Dijkman, Kumuda Dorai, Paul Dorosh, Ehsan Dulloo, Shenggen Fan, Jean-Marc Faurès, Edith Fernández-Baca, Cornelia Butler Flora, Louise O. Fresco, Lucy Garret, Hafez Ghanem, Marius Gilbert, Meredith Giordano, Andrew Hall, Matthias Halwart, Sue Hartley, Patrick P. Kalas, Gina Kennedy, Zeyaur Khan, Misael Kokwe, Rattan Lal, Wilfrid Legg, Preet Lidder, Leslie Lipper, Juliana C. Lopes, Yuelai Lu, Eduardo Mansur, Alexandre Meybeck, Weimin Miao, Charles Midega, Jamie Morrison, William Murray, David Neven, Hanh Nguyen, Ephraim Nkonya, Carolyn Opio, Shivaji Pandey, Monica Petri, Ugo Pica-Ciamarra, John Pickett, Prabhu Pingali, Jimmy Pittchar, Jules Pretty, Ewald Rametsteiner, Sherman Robinson, Timothy Paul Robinson, Dominic Rowland, Harpinder Sandhu, Fritz Schneider, Rachid Serraj, Andrea Sonnino, Kostas Stamoulis, Austin Stankus, Henning Steinfeld, Rudresh Kumar Sugam, Terry C.H. Sunderland, Berhe Tekola, James Thurlow, Olcay Ünver, Cora van Oosten, Rob Vos, Ren Wang, Keith Wiebe, and Wei Zhang
- Published
- 2019
32. Demographic Change, Agriculture, and Rural Poverty
- Author
-
Ben Davis, James Thurlow, and Paul A. Dorosh
- Subjects
Industrialisation ,Rural poverty ,Poverty ,business.industry ,Agriculture ,Urbanization ,Development economics ,Population growth ,Food systems ,business ,Downstream (petroleum industry) - Abstract
Population growth and urbanization are associated with economic development. Structural transformation entails workers leaving less productive agriculture and moving to more productive industries, often in urban centers. Population growth slows with development, leading to greater dependence on capital and technology rather than on labor. This was Asia’s successful pathway. Sub-Saharan Africa (SSA) is also transforming, but far less than other regions are and with its own distinctive features. Though Africa is urbanizing, rapid population growth means that rural populations are still expanding. While African workers also are leaving agriculture, they do so at a slower pace than workers in Asia and are finding work in less productive services rather than in manufacturing. Such “urbanization without industrialization” raises concerns about Africa’s ability to create enough jobs for its urban workforce and underscores the need for continued focus on rural Africa. This chapter reviews the linkages between urbanization, agriculture and rural poverty in SSA, where most of the world’s poor will soon reside. It suggests that much of the economic growth and structural change that Africa enjoyed over the past two decades, attributable to a shift out of agriculture, was in fact an expansion of downstream components of the agriculture food system. Like agriculture, many downstream activities have strong linkages to poverty reduction. Governments concerned about jobs and poverty will need to raise productivity, not only in agriculture, but also throughout the entire food system. Since many downstream processing and trading activities are in towns and cities, promoting future poverty reduction will require greater alignment between agricultural and urban policies. Demographic change and rural-urban linkages will continue to be powerful drivers of global poverty reduction, but ensuring inclusive transformation will require broader development perspectives and policy coordination.
- Published
- 2019
33. The impacts of price regulation on price dispersion in Australia's retail electricity markets
- Author
-
Tim Nelson, Alan Rai, Ryan Esplin, and Ben Davis
- Subjects
Energy ,business.industry ,020209 energy ,TheoryofComputation_GENERAL ,02 engineering and technology ,Monetary economics ,Price discrimination ,010501 environmental sciences ,Management, Monitoring, Policy and Law ,01 natural sciences ,Energy policy ,Competition (economics) ,Deregulation ,General Energy ,0202 electrical engineering, electronic engineering, information engineering ,Price dispersion ,Electricity market ,Business ,Electricity ,Electricity retailing ,0105 earth and related environmental sciences - Abstract
Price deregulation in Australia's National Electricity Market has led to increased competition and greater price dispersion in retail electricity markets. However, recent increases in electricity prices and concerns around disengaged customers have led policy makers to impose a ‘default offer’ to cap retail electricity prices. In this article, we develop a model that demonstrates the mechanism through which a price cap leads to the withdrawal of the lowest priced offers from the market, in effect reducing the benefits available to customers that ‘shop around’. We calculate a measure of actual price dispersion showing that a compression of offers since the price cap was imposed has reduced the returns from search by 2.3 per cent, or $37 per year on average. We argue that the important issue of vulnerable, disengaged customers on high priced offers is best addressed through non-price regulation policy options, such as an auction for the right to serve customers that are both vulnerable and disengaged.
- Published
- 2020
34. Progression to deep sleep is characterized by changes to BOLD dynamics in sensory cortices
- Author
-
Ben Davis, Helmut Laufs, Uri Hasson, Enzo Tagliazucchi, and Jorge Jovicich
- Subjects
Male ,WAKEFULNESS ,Cognitive Neuroscience ,BRAIN NETWORK ,Sensory system ,Electroencephalography ,Somatosensory system ,Brain mapping ,Article ,050105 experimental psychology ,DEFAULT MODE NETWORK ,SLOW-WAVE SLEEP ,RESTING-STATE FMRI ,EYE-MOVEMENT SLEEP ,FUNCTIONAL CONNECTIVITY ,FLUCTUATIONS ,SIGNAL ,DEACTIVATION ,Young Adult ,03 medical and health sciences ,0302 clinical medicine ,Neural Pathways ,Image Processing, Computer-Assisted ,medicine ,Humans ,0501 psychology and cognitive sciences ,Wakefulness ,Slow-wave sleep ,Brain Mapping ,medicine.diagnostic_test ,05 social sciences ,Motor Cortex ,Signal Processing, Computer-Assisted ,Somatosensory Cortex ,Magnetic Resonance Imaging ,Sleep in non-human animals ,medicine.anatomical_structure ,Neurology ,Female ,Sleep ,Psychology ,Neuroscience ,030217 neurology & neurosurgery ,Motor cortex - Abstract
Sleep has been shown to subtly disrupt the spatial organization of functional connectivity networks in the brain, but in a way that largely preserves the connectivity within sensory cortices. Here we evaluated the hypothesis that sleep does impact sensory cortices, but through alteration of activity dynamics. We therefore examined the impact of sleep on hemodynamics using a method for quantifying non-random, high frequency signatures of the blood-oxygen-level dependent (BOLD) signal (amplitude variance asymmetry; AVA). We found that sleep was associated with the elimination of these dynamics in a manner that is restricted to auditory, motor and visual cortices. This elimination was concurrent with increased variance of activity in these regions. Functional connectivity between regions showing AVA during wakefulness maintained a relatively consistent hierarchical structure during wakefulness and N1 and N2 sleep, despite a gradual reduction of connectivity strength as sleep progressed. Thus, sleep is related to elimination of high frequency non-random activity signatures in sensory cortices that are robust during wakefulness. The elimination of these AVA signatures conjointly with preservation of the structure of functional connectivity patterns may be linked to the need to suppress sensory inputs during sleep while still maintaining the capacity to react quickly to complex multimodal inputs., Highlights • We examined time-domain dynamics of BOLD activity during sleep. • We used a method previously showing unique dynamics in sensory cortices during wakefulness. • We find elimination of wakefulness dynamics during N2 and N3 sleep, but not N1.
- Published
- 2016
35. 4 Examining x, y, and z vibration patterns of commercial pig transport trailers from the farm to the abattoir
- Author
-
John M Gonzalez, Jamison G Williams, Terry A. Houser, Daniel Flippo, Benjamin Keith Morris, Kari K Turner, Edwin Brokesh, Ben Davis, and Francisco Najar-Villarreal
- Subjects
Vibration ,Abstracts ,Genetics ,Animal Science and Zoology ,General Medicine ,Biology ,Food Science ,Marine engineering - Abstract
The objective of this study was to measure and examine 3-axis acceleration data from 6 locations within commercial transport trailers shipping market pigs. Over winter months (December through February) of 2018 to 2019 and 2019 to 2020, 16 pot-belly and 14 straight-deck trailer loads of market pigs were measured from 2 producers located in Kansas and North Carolina, respectively. Six accelerometers were placed in protective cases and affixed to the underside of the floor in the approximate center of the front compartment, middle of the trailer, and back compartment of the top and bottom decks. Data were post-processed to calculate power spectral density (PSD) functions and corresponding root mean square (RMS) accelerations. The PSDs lend insight into the vibrational frequency content of the trailers, while the RMS values indicate the severity of the vibration over the duration of each trip. With the exception of the lower aft portion of the trailer where levels are significantly higher, RMS values were consistent across trips and largely similar between sensor location and axis. Accelerations ranged between 0.06 and 0.18 g and varied in time, indicating data were non-stationarity. The PSD results reveal a largely broadband frequency response of the loaded trailers between 0 and 50 Hz, especially for sensors on the lower deck. Preliminary analysis of the data indicates the severity of vibrations experienced by pigs during transport would be considered uncomfortable by humans.
- Published
- 2020
36. Right external iliac artery thrombus following the use of resuscitative endovascular balloon occlusion of the aorta for placenta accreta
- Author
-
William C Beck, Jordan W Greer, Anna Privratsky, John R Taylor, Colleen Flanagan, Ben Davis, Mary K. Kimbrough, Avi Bhavaraju, Ronald D. Robertson, and Kevin W. Sexton
- Subjects
Abdominal pain ,medicine.medical_specialty ,Aorta ,Hysterectomy ,business.industry ,Placenta accreta ,medicine.medical_treatment ,Case Report ,030208 emergency & critical care medicine ,Vascular surgery ,Balloon ,medicine.disease ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,Blood pressure ,medicine.artery ,Medicine ,030212 general & internal medicine ,medicine.symptom ,Thrombus ,business - Abstract
A 33-year-old female, 32 weeks and 1 day gestation, with known placenta accreta who presented to the emergency department with 2 h of severe abdominal pain, nausea and vomiting. She became hypotensive and underwent emergency cesarean section. Emergency general surgery was consulted for placement of a resuscitative endovascular balloon for aortic occlusion (REBOA). After successful delivery, the balloon was inflated in zone 3 and systolic blood pressure rose from 70 to 170 mmHg. The patient underwent hysterectomy for ongoing hemorrhage. The patient was taken to the surgical intensive care unit. The patient was noted to have pulses following removal of the sheath. Arterial brachial indices and arterial duplex was performed 48 h after sheath removal. The patient was found to have complete occlusion of the right external iliac artery. Vascular surgery was consulted and cut-down performed with thrombus removal via fogarty catheter. The patient was discharged 2 days later without further complication.
- Published
- 2018
37. Dilated cardiomyopathy secondary to acute pancreatitis caused by hypertriglyceridemia
- Author
-
Ronald D. Robertson, Mary K. Kimbrough, Ben Davis, Avi Bhavaraju, Joseph C. Jensen, Anna Privratsky, Jordan W Greer, Kevin W. Sexton, John R Taylor, and William C Beck
- Subjects
medicine.medical_specialty ,business.industry ,medicine.medical_treatment ,Hypertriglyceridemia ,Case Report ,Dilated cardiomyopathy ,Emergency department ,030204 cardiovascular system & hematology ,medicine.disease ,Surgery ,03 medical and health sciences ,0302 clinical medicine ,medicine.anatomical_structure ,Heart failure ,Edema ,medicine ,Abdomen ,Acute pancreatitis ,030211 gastroenterology & hepatology ,Renal replacement therapy ,medicine.symptom ,business - Abstract
A 30-year-old male presented to an outside facility with acute pancreatitis and triglycerides of 1594. He was transferred to our facility after becoming febrile, hypoxic and in acute renal failure with triglycerides of 4243. CT scan performed showed wall-off pancreatic necrosis. He underwent continuous renal replacement therapy and his acute renal failure resolved. He was treated with broad spectrum antibiotics and discharged. He developed a fever to 101 a week later and was found to have a large infected pancreatic pseudocyst. This was managed with an IR placed drain. This was continued for 6 weeks. He came to the emergency department several weeks later with shortness of breath and 3+ edema to bilateral lower extremities and lower abdomen. TTE performed showed an EF of 15%. He was diuresed 25 L during that stay. His heart failure was medically managed. We present this case of dilated cardiomyopathy secondary to acute pancreatitis.
- Published
- 2018
38. Defining severe traumatic brain injury readmission rates and reasons in a rural state
- Author
-
James Reed Gardner, John R Taylor, Austin Porter, Mary K. Kimbrough, Avi Bhavaraju, William C Beck, Kevin W. Sexton, Ben Davis, and Saleema A. Karim
- Subjects
Chronic condition ,medicine.medical_specialty ,Rehabilitation ,Traumatic brain injury ,business.industry ,medicine.medical_treatment ,Critical Care and Intensive Care Medicine ,medicine.disease ,Chest pain ,Emergency medicine ,Epidemiology ,medicine ,Dementia ,Surgery ,Diagnosis code ,medicine.symptom ,business ,Depression (differential diagnoses) - Abstract
BackgroundReadmissions after a traumatic brain injury (TBI) have significant impact on long-term patient outcomes through interruption of rehabilitation. This study examined readmissions in a rural population, hypothesizing that readmitted patients after TBI will be older and have more comorbidities than those not readmitted.MethodsDischarge data on all patients 15 years and older who were admitted to an Arkansas-based hospital for TBI were obtained from the Arkansas Hospital Discharge Data System from 2010 to 2014. This data set includes diagnoses (principal discharge diagnosis, up to 3 external cause of injury codes, 18 diagnosis codes using the International Classification of Disease, 9th Edition, Clinical Modifications), age, gender, and inpatient costs. Hospital Cost and Utilization Project Clinical Classification and Chronic Condition Indicator were used to identify chronic disease and body systems affected in principal diagnosis.ResultsOf the 3114 cases of significant head trauma, more than two-thirds were attributed to fall injuries, with motor vehicle crashes accounting for 20% of the remainder. The mean length of stay was 6.5 days. 691 of these patients were admitted to an Arkansas hospital in the following year, totaling 1368 readmissions. Of the readmissions, 16.4% of patients were admitted for altered mental status, 12.9% with shortness of breath (SOB), and 9.4% with chest pain. Mental disorders (psychosis, dementia, and depression) and organic nervous symptoms (Alzheimer’s disease, encephalopathy, and epilepsy) were the primary source of readmissions. More than one-third of the patients were admitted in the following year for chronic diseases such as heart failure (8.6%), psychosis (5.2%), and cerebral artery occlusion (4.1%).DiscussionThis study showed that there is a significant rate of readmissions in the year after a diagnosis of TBI. Complications with existing chronic diseases are among the most reported reasons for admission in this time period, demonstrating the effect severe head trauma has on long-term treatment.Level of evidenceLevel IV, Retrospective epidemiological study.
- Published
- 2018
39. A combinatorial framework to quantify peak/pit asymmetries in complex dynamics
- Author
-
Ryan Flanagan, Enzo Tagliazucchi, Helmut Laufs, Uri Hasson, Lucas Lacasa, Ben Davis, Jacopo Iacovacci, and Netherlands Institute for Neuroscience (NIN)
- Subjects
Computer science ,Science ,NEUROIMAGING ,Ciencias Físicas ,Chaotic ,FOS: Physical sciences ,Otras Ciencias Físicas ,01 natural sciences ,Quantitative Biology - Quantitative Methods ,Article ,010305 fluids & plasmas ,purl.org/becyt/ford/1 [https] ,Ciencias Biológicas ,0103 physical sciences ,Journal Article ,Statistical physics ,ddc:610 ,010306 general physics ,purl.org/becyt/ford/1.6 [https] ,Quantitative Methods (q-bio.QM) ,Multidisciplinary ,Series (mathematics) ,Stochastic process ,purl.org/becyt/ford/1.3 [https] ,Complex network ,Biofísica ,STOCHASTIC PROCESSES ,Maxima and minima ,Complex dynamics ,Range (mathematics) ,FOS: Biological sciences ,Physics - Data Analysis, Statistics and Probability ,Quantitative Biology - Neurons and Cognition ,Medicine ,Neurons and Cognition (q-bio.NC) ,Data Analysis, Statistics and Probability (physics.data-an) ,CIENCIAS NATURALES Y EXACTAS - Abstract
We explore a combinatorial framework which efficiently quantifies the asymmetries between minima and maxima in local fluctuations of time series. We first showcase its performance by applying it to a battery of synthetic cases. We find rigorous results on some canonical dynamical models (stochastic processes with and without correlations, chaotic processes) complemented by extensive numerical simulations for a range of processes which indicate that the methodology correctly distinguishes different complex dynamics and outperforms state of the art metrics in several cases. Subsequently, we apply this methodology to real-world problems emerging across several disciplines including cases in neurobiology, finance and climate science. We conclude that differences between the statistics of local maxima and local minima in time series are highly informative of the complex underlying dynamics and a graph-theoretic extraction procedure allows to use these features for statistical learning purposes. Fil: Hasson, Uri. University of Chicago; Estados Unidos. University of Trento; Italia Fil: Iacovacci, Jacopo. The Francis Crick Institute; Reino Unido. Imperial College London; Reino Unido Fil: Davis, Ben. University of Trento; Italia Fil: Flanagan, Ryan. Queen Mary University of London; Reino Unido Fil: Tagliazucchi, Enzo Rodolfo. Netherlands Institute for Neuroscience; Países Bajos Fil: Laufs, Helmut. Goethe Universitat Frankfurt; Alemania. University Hospital Kiel; Alemania Fil: Lacasa, Lucas. Queen Mary University of London; Reino Unido
- Published
- 2018
40. Is It Safe to Fly Patients with Penetrating Trauma in a Rural State?
- Author
-
Ben Davis, Rebecca Reif, Avi Bhavaraju, John R Taylor, Saleema A. Karim, William C Beck, Kevin W. Sexton, and Jordan W Greer
- Subjects
Adult ,Male ,Rural Population ,medicine.medical_specialty ,Adolescent ,Wounds, Penetrating ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Blunt ,Injury Severity Score ,Trauma Centers ,medicine ,Humans ,Retrospective Studies ,business.industry ,Trauma center ,Glasgow Coma Scale ,Retrospective cohort study ,Air Ambulances ,Middle Aged ,medicine.disease ,Triage ,Logistic Models ,Blunt trauma ,030220 oncology & carcinogenesis ,Emergency medicine ,030211 gastroenterology & hepatology ,Surgery ,Female ,business ,Penetrating trauma - Abstract
There is limited data pertaining to the triage and transportation of patients with penetrating trauma in rural states. Large urban trauma centers have found rapid transport to be beneficial even when done by nonemergency medical staff. However, there is limited application to a rural state with only a single level 1 trauma center.This a retrospective observational study of 854 trauma patients transported by helicopter emergency services between 2009 and 2015 to the state's only level 1 trauma center.After excluding patients with other injuries or lack of data, 854 patients underwent final analysis. Compared with penetrating trauma, blunt trauma had a significantly different chance of survival (92.0% versus 81.2%, P = 0.002) and a significantly different injury severity score (17 ± 12 versus 12 ± 9, P = 0.002). After controlling for blunt injuries, age, gender, injury severity score, tachycardia, tachypnea, hypotension, glasgow coma scale, and dispatch to hospital arrival time in multivariate analysis, blunt trauma had higher odds of survival than penetrating trauma (OR, 5.97; 95% CI, 2.52-14.12; P = 0.001 = 1). Gender, tachycardia, tachypnea, and dispatch to arrival time did not impact a patient's likelihood of survival.Penetrating trauma has a higher mortality when compared with blunt trauma in Helicopter Emergency Services transported patients in a rural state. Perhaps a new algorithm in the management of penetrating trauma would include hemorrhage control at a locoregional hospital before definitive care. Further study is required to understand the exact variables that lead to a higher mortality in penetrating trauma in a rural state.
- Published
- 2018
41. Treatment-seeking patterns for malaria in pharmacies in five sub-Saharan African countries
- Author
-
Ben Davis, Joseph Saba, Etienne Audureau, Joël Ladner, Nutrition, inflammation et dysfonctionnement de l'axe intestin-cerveau (ADEN), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institute for Research and Innovation in Biomedicine (IRIB), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), UNIROUEN - UFR Santé (UNIROUEN UFR Santé), Normandie Université (NU)-Normandie Université (NU), Département d'épidémiologie et de promotion de la santé [Rouen], CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Axios International France, Service de santé publique [Mondor], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Henri Mondor-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), Institut National de la Santé et de la Recherche Médicale (INSERM)-Université de Rouen Normandie (UNIROUEN), and Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Male ,Psychological intervention ,Health Care Sector ,Ghana ,Tanzania ,0302 clinical medicine ,Surveys and Questionnaires ,Uganda ,030212 general & internal medicine ,Child ,Rapid diagnostic test ,biology ,medicine.diagnostic_test ,ACT drugs ,Commerce ,Artemisinins ,3. Good health ,Infectious Diseases ,Child, Preschool ,Drug Therapy, Combination ,Female ,Private Sector ,Adult ,medicine.medical_specialty ,lcsh:Arctic medicine. Tropical medicine ,Adolescent ,lcsh:RC955-962 ,030231 tropical medicine ,Nigeria ,Pharmacy ,Drug Prescriptions ,lcsh:Infectious and parasitic diseases ,03 medical and health sciences ,Antimalarials ,Young Adult ,Environmental health ,parasitic diseases ,medicine ,Blood test ,Humans ,lcsh:RC109-216 ,Medical prescription ,Africa South of the Sahara ,Pharmacies ,business.industry ,Diagnostic Tests, Routine ,Public health ,Research ,medicine.disease ,biology.organism_classification ,Kenya ,Malaria ,Treatment ,Optometry ,Parasitology ,[SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie ,business ,Case Management - Abstract
Background Artemisinin-based combination therapy (ACT) is recommended as the first-line anti-malarial treatment strategy in sub-Saharan African countries. WHO policy recommends parasitological confirmation by microscopy or rapid diagnostic test (RDT) in all cases of suspected malaria prior to treatment. Gaps remain in understanding the factors that influence patient treatment-seeking behaviour and anti-malarial drug purchase decisions in the private sector. The objective of this study was to identify patient treatment-seeking behaviour in Ghana, Kenya, Nigeria, Tanzania, and Uganda. Methods Face-to-face patient interviews were conducted at a total of 208 randomly selected retail outlets in five countries. At each outlet, exit interviews were conducted with five patients who indicated they had come seeking anti-malarial treatment. The questionnaire was anonymous and standardized in the five countries and collected data on different factors, including socio-demographic characteristics, history of illness, diagnostic practices (i.e. microscopy or RDT), prescription practices and treatment purchase. The price paid for the treatment was also collected from the outlet vendor. Results A total of 994 patients were included from the five countries. Location of malaria diagnosis was significantly different in the five countries. A total of 484 blood diagnostic tests were performed, (72.3% with microscopy and 27.7% with RDT). ACTs were purchased by 72.5% of patients who had undergone blood testing and 86.5% of patients without a blood test, regardless of whether the test result was positive or negative (p
- Published
- 2017
42. Encouraging patients to exercise: motivational interviewing, observation and learning
- Author
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David Wellsted, Patricia M. Wilson, Ken Farrington, Ben Davis, Sivakumar Sridharan, Andy Scarlino, Jonathan Reston, Rebecca Bierraugel, Rebecca Scarlino, Maria Da Silva Gane, and Enric Vilar
- Subjects
medicine.medical_specialty ,Self-management ,business.industry ,medicine.medical_treatment ,Motivational interviewing ,Boredom ,Health problems ,Intervention (counseling) ,Employee engagement ,medicine ,Physical therapy ,Observational learning ,medicine.symptom ,business ,Dialysis - Abstract
The physical and psychological health benefits of exercise are well established, yet patients undergoing dialysis commonly live sedentary lives, contributing to comorbidities with other health problems. Motivational interviewing was used to promote exercise during dialysis; the levels of patient exercise correlated positively with the fidelity of the intervention delivery and levels of change talk, and correlated negatively with the levels of sustain talk. Patients were also motivated by seeing other patients engage in intradialytic exercise, and this was an effective method to increase the number of patients engaging in exercise. Patients welcomed the opportunity to try out the exercise; they were motivated by improvements to their health as well as reductions in their boredom and restlessness during a dialysis session. Sustainability proved to be a key issue and efforts should be made to improve staff engagement in promoting an exercise culture that helps continued exercise uptake.
- Published
- 2015
43. Connectivity in the human brain dissociates entropy and complexity of auditory inputs
- Author
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Ben Davis, Uri Hasson, Vittorio Iacovella, and Samuel A. Nastase
- Subjects
Adult ,Male ,Computer science ,Entropy ,Cognitive Neuroscience ,Models, Neurological ,Monotonic function ,computer.software_genre ,Article ,Entropy (classical thermodynamics) ,Functional neuroimaging ,Neural Pathways ,Image Processing, Computer-Assisted ,Humans ,Entropy (information theory) ,Functional integration ,Entropy (energy dispersal) ,Entropy (arrow of time) ,Randomness ,Brain Mapping ,Entropy (statistical thermodynamics) ,Uncertainty ,Probabilistic logic ,Brain ,Complexity ,Magnetic Resonance Imaging ,Generative model ,Simplicity ,Neurology ,Auditory Perception ,Female ,Data mining ,Prediction ,Algorithm ,computer ,Entropy (order and disorder) - Abstract
Complex systems are described according to two central dimensions: (a) the randomness of their output, quantified via entropy; and (b) their complexity, which reflects the organization of a system's generators. Whereas some approaches hold that complexity can be reduced to uncertainty or entropy, an axiom of complexity science is that signals with very high or very low entropy are generated by relatively non-complex systems, while complex systems typically generate outputs with entropy peaking between these two extremes. In understanding their environment, individuals would benefit from coding for both input entropy and complexity; entropy indexes uncertainty and can inform probabilistic coding strategies, whereas complexity reflects a concise and abstract representation of the underlying environmental configuration, which can serve independent purposes, e.g., as a template for generalization and rapid comparisons between environments. Using functional neuroimaging, we demonstrate that, in response to passively processed auditory inputs, functional integration patterns in the human brain track both the entropy and complexity of the auditory signal. Connectivity between several brain regions scaled monotonically with input entropy, suggesting sensitivity to uncertainty, whereas connectivity between other regions tracked entropy in a convex manner consistent with sensitivity to input complexity. These findings suggest that the human brain simultaneously tracks the uncertainty of sensory data and effectively models their environmental generators., Highlights • Complexity science holds that highly ordered and random signals have low complexity. • We examine whether effective connectivity tracks both stimulus entropy and complexity. • Connectivity tracked entropy both linearly and via an inverse U-shaped profile. • Both profiles were identified for hippocampal and anterior cingulate networks.
- Published
- 2015
44. Cross-modal and non-monotonic representations of statistical regularity are encoded in local neural response patterns
- Author
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Ben Davis, Uri Hasson, and Samuel A. Nastase
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Adult ,Male ,Multivariate statistics ,Statistical regularity ,genetic structures ,Computer science ,Cognitive Neuroscience ,Entropy ,Monotonic function ,Stimulus (physiology) ,050105 experimental psychology ,Regularity ,03 medical and health sciences ,Young Adult ,0302 clinical medicine ,Stimulus modality ,Neuroimaging ,Encoding (memory) ,medicine ,Image Processing, Computer-Assisted ,Entropy (information theory) ,Humans ,0501 psychology and cognitive sciences ,Generalizability theory ,Sensitivity (control systems) ,Association (psychology) ,Complexity ,Multimodal ,Prediction ,Brain Mapping ,Modality (human–computer interaction) ,business.industry ,05 social sciences ,Brain ,Pattern recognition ,Human brain ,Magnetic Resonance Imaging ,medicine.anatomical_structure ,Neurology ,Acoustic Stimulation ,Auditory Perception ,Visual Perception ,Female ,Artificial intelligence ,business ,030217 neurology & neurosurgery ,Photic Stimulation - Abstract
Current models of brain function assign a central role to predictive processes calibrated to the structure of the environment. Although several neuroimaging studies have examined how the human brain encodes the uncertainty of incoming stimuli, most have relied exclusively on experimental manipulations of uncertainty in which stimuli were presented in a single sensory modality, and further assumed that neural responses vary monotonically with uncertainty. This has left a gap in theoretical development with respect to two core issues: i) are there cross-modal brain systems that encode input uncertainty in way that generalizes across sensory modalities, and ii) are there brain systems that track input uncertainty in a non-monotonic fashion? Here we directly addressed the issues of cross-modal and non-monotonic processing by quantifying neural sensitivity to uncertainty in auditory, visual and audiovisual inputs using multivariate pattern analysis. We found signatures of cross-modal encoding in frontoparietal, orbitofrontal, and association cortices using a searchlight cross-classification analysis where classifiers trained to discriminate levels of uncertainty in one modality were tested in another modality. Additionally, we found widespread systems encoding uncertainty non-monotonically using classifiers trained to discriminate intermediate levels of uncertainty from both the highest and lowest uncertainty levels. These findings comprise the first comprehensive report of cross-modal and non-monotonic neural sensitivity to statistical regularities in the environment, and suggest that conventional paradigms testing for monotonic responses to uncertainty in a single sensory modality may have limited generalizability.
- Published
- 2017
45. Societal impact of dengue outbreaks: Stakeholder perceptions and related implications. A qualitative study in Brazil, 2015
- Author
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Etienne Audureau, Ben Davis, Joseph Saba, Marie-Hélène Besson, Joël Ladner, Mariana Figueiredo Rodrigues, Nutrition, inflammation et dysfonctionnement de l'axe intestin-cerveau (ADEN), Université de Rouen Normandie (UNIROUEN), Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM), Institute for Research and Innovation in Biomedicine (IRIB), Normandie Université (NU)-Normandie Université (NU)-Centre National de la Recherche Scientifique (CNRS)-Institut National de la Santé et de la Recherche Médicale (INSERM), UNIROUEN - UFR Santé (UNIROUEN UFR Santé), Normandie Université (NU)-Normandie Université (NU), Département d'épidémiologie et de promotion de la santé [Rouen], CHU Rouen, Normandie Université (NU)-Normandie Université (NU)-Université de Rouen Normandie (UNIROUEN), Normandie Université (NU), Axios International France, Service de santé publique [Mondor], Assistance publique - Hôpitaux de Paris (AP-HP) (AP-HP)-Hôpital Henri Mondor-Université Paris-Est Créteil Val-de-Marne - Paris 12 (UPEC UP12), and Normandie Université (NU)-Normandie Université (NU)-Institut National de la Santé et de la Recherche Médicale (INSERM)-Centre National de la Recherche Scientifique (CNRS)
- Subjects
Viral Diseases ,Medical Doctors ,Economics ,Disease Outbreaks ,Health Care Providers ,Social Sciences ,Geographical locations ,Dengue Fever ,Dengue ,Governments ,0302 clinical medicine ,Cost of Illness ,Environmental protection ,Surveys and Questionnaires ,Medicine and Health Sciences ,Brazil/epidemiology ,030212 general & internal medicine ,Economic impact analysis ,Political authorities ,lcsh:Public aspects of medicine ,MESH: Brazil/epidemiology ,Dengue/epidemiology ,1. No poverty ,Societal impact of nanotechnology ,Qualitative Studies ,3. Good health ,Professions ,Infectious Diseases ,Research Design ,Brazil ,Research Article ,Neglected Tropical Diseases ,medicine.medical_specialty ,lcsh:Arctic medicine. Tropical medicine ,Infectious Disease Control ,lcsh:RC955-962 ,Political Science ,030231 tropical medicine ,Research and Analysis Methods ,03 medical and health sciences ,Health Economics ,Environmental health ,Physicians ,medicine ,Government ,Health economics ,business.industry ,Public health ,Public Health, Environmental and Occupational Health ,Outbreak ,lcsh:RA1-1270 ,South America ,Tropical Diseases ,Economic Analysis ,Health Care ,Economic Impact Analysis ,Communicable Disease Control ,Perception ,Population Groupings ,[SDV.SPEE]Life Sciences [q-bio]/Santé publique et épidémiologie ,People and places ,business ,Municipal Government ,Qualitative research - Abstract
Background The growing burden of dengue in many countries worldwide and the difficulty of preventing outbreaks have increased the urgency to identify alternative public health management strategies and effective approaches to control and prevent dengue outbreaks. The objectives of this study were to understand the impact of dengue outbreak on different stakeholders in Brazil, to explore their perceptions of approaches used by governmental authorities to control and prevent dengue outbreaks and to define the challenges and implications of preventing future outbreaks. Methods In 2015, a qualitative study was conducted in two urban states in Brazil: São Paulo, which was experiencing an outbreak in 2015, and Rio de Janeiro, which experienced outbreaks in 2011 and 2012. Face-to-face interviews using a semi-structured questionnaire were conducted with nine different categories of stakeholders: health workers (physicians, nurses), hospital administrators, municipal government representatives, community members and leaders, school administrators, business leaders and vector control managers. Interviews were focused on the following areas: impact of the dengue outbreak, perceptions of control measures implemented by governmental authorities during outbreaks and challenges in preventing future dengue outbreaks. Results A total of 40 stakeholders were included in the study. Health workers and community members reported longer waiting times at hospitals due to the increased number of patients receiving care for dengue-related symptoms. Health workers and hospital administrators reported that there were no major interruptions in access to care. Overall financial impact of dengue outbreaks on households was greatest for low-income families. Despite prevention and control campaigns implemented between outbreak periods, various stakeholders reported that dengue prevention and control efforts performed by municipal authorities remained insufficient, suggesting that efforts should be reinforced and better coordinated by governmental authorities, particularly during outbreak periods. Conclusion The study shows that a dengue outbreak has a multisectorial impact in the medical, societal, economic and political sectors. The study provides useful insights and knowledge in different stakeholder populations that could guide local authorities and government officials in planning, designing and initiating public health programs. Research focused on a better understanding of how communities and political authorities respond to dengue outbreaks is a necessary component for designing and implementing plans to decrease the incidence and impact of dengue outbreaks in Brazil., Author summary Since the beginning of the 21st century, dengue fever has been a significant vector-borne arboviral disease; actually more than 3.9 billion people are at risk of infection in 128 countries. Dengue has become an increasing public health concern in Latin America, especially in Brazil, which has the highest incidence rate of dengue. Researches are needed to gain in-depth understanding of stakeholder and community reactions to outbreak and to explore the societal impact of dengue outbreaks. In 2015, a qualitative study was conducted in two urban states in Brazil, which experienced recent outbreaks. Longer waiting times at hospitals due to the increased number of patients receiving care for dengue-related symptoms were reported, but without interruptions in access to care. Various stakeholders reported that dengue prevention and control efforts performed by municipal authorities remained insufficient. The consequences of a dengue outbreak reach far beyond the patients, undermining medical, social, economic and political sectors. Research focused on a better understanding of how communities and political authorities respond to dengue outbreaks is a necessity for designing and implementing plans to control dengue outbreaks.
- Published
- 2017
46. Application of Off-Rate Screening in the Identification of Novel Pan-Isoform Inhibitors of Pyruvate Dehydrogenase Kinase
- Author
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Stephen Stokes, Patrick C. Mahon, Alan D. Robertson, Jalanie D’Alessandro, Paul Webb, Charles Parry, Lisa Baker, Natalia Matassova, Nicholas G. M. Davies, Sean McKenna, Andrew Massey, Rachel Parsons, Yikang Wang, Macias Alba, Paul Brough, Ben Davis, Michael Wood, Simon Bedford, Jonathan D. Moore, Christopher J. Northfield, Loic le Strat, Stephen D. Roughley, Daniel Maddox, Seema Chavda, James Brooke Murray, Allan E. Surgenor, Johannes W. G. Meissner, Terry Shaw, Heather Simmonite, Stefaniak Emma Jayne, Victoria Chell, Neil Whitehead, and Kirsten Brown
- Subjects
0301 basic medicine ,Male ,Models, Molecular ,Pyruvate dehydrogenase lipoamide kinase isozyme 1 ,Pyruvate dehydrogenase kinase ,Pyruvate dehydrogenase phosphatase ,Protein Serine-Threonine Kinases ,03 medical and health sciences ,chemistry.chemical_compound ,0302 clinical medicine ,Adenosine Triphosphate ,Cell Line, Tumor ,Drug Discovery ,Transferase ,Humans ,Protein Isoforms ,HSP90 Heat-Shock Proteins ,Phosphorylation ,Protein Kinase Inhibitors ,chemistry.chemical_classification ,Prostatic Neoplasms ,Pyruvate Dehydrogenase Acetyl-Transferring Kinase ,Hit to lead ,Molecular biology ,030104 developmental biology ,Enzyme ,chemistry ,Biochemistry ,030220 oncology & carcinogenesis ,Drug Design ,Molecular Medicine ,Adenosine triphosphate - Abstract
Libraries of nonpurified resorcinol amide derivatives were screened by surface plasmon resonance (SPR) to determine the binding dissociation constant (off-rate, kd) for compounds binding to the pyruvate dehydrogenase kinase (PDHK) enzyme. Parallel off-rate measurements against HSP90 and application of structure-based drug design enabled rapid hit to lead progression in a program to identify pan-isoform ATP-competitive inhibitors of PDHK. Lead optimization identified selective sub-100-nM inhibitors of the enzyme which significantly reduced phosphorylation of the E1α subunit in the PC3 cancer cell line in vitro.
- Published
- 2017
47. Satisfaction and Clinical Outcomes Among Patients with Immediately Loaded Mandibular Overdentures Supported by One or Two Dental Implants: Results of a 5-Year Prospective Randomized Clinical Trial
- Author
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Ben Davis, Robert W. Loney, Jack D. Gerrow, Mats Kronstrom, and Lars Hollender
- Subjects
Adult ,Male ,Immediate Dental Implant Loading ,Alveolar Bone Loss ,Dentistry ,Oral Health ,Mandible ,Oral health ,law.invention ,03 medical and health sciences ,0302 clinical medicine ,Patient satisfaction ,Randomized controlled trial ,law ,Medicine ,Humans ,Dental Restoration Failure ,Prospective Studies ,Prospective cohort study ,Aged ,Dental Implants ,business.industry ,Dental prosthesis ,Mean age ,030206 dentistry ,General Medicine ,Middle Aged ,Implant stability quotient ,Denture, Overlay ,Denture Retention ,Treatment Outcome ,Patient Satisfaction ,Female ,Implant ,Dental Prosthesis, Implant-Supported ,Oral Surgery ,business ,030217 neurology & neurosurgery ,Follow-Up Studies - Abstract
Purpose: The purpose of this study was to evaluate patient satisfaction and clinical outcomes among subjects with mandibular overdentures supported by one or two immediately placed dental implants 5 years after loading. Materials and Methods: Thirty-six subjects (16 men and 20 women) received one or two dental implants in the anterior mandible, and all implants were loaded the day of surgery. Subjects were scheduled for follow-up 3-, 6-, and 12 months after implant placement and thereafter annually for 4 more years. Patient satisfaction scores were measured with the Oral Health Impact Profile-EDENT (OHIPEDENT) questionnaire. Results: Seventeen subjects (7 male and 10 female) with a mean age of 59.4 years (range, 44 to 74 years) were available for the 5-year follow-up examination. Nine subjects with 10 failing implants were excluded during the first year and nine subjects were lost to follow-up. No implants failed between the 12- and 60-month follow-up examinations, and the need for denture maintenance was low. Mean peri-implant bone change was 0.92 mm, and the Spearman test failed to show correlation between the insertion torque value and implant stability quotient. Patient satisfaction scores increased significantly when compared with baseline values and continued to be high for both groups, with no significant differences. Conclusion: Ten implants in nine subjects failed early, but no failures were observed after the 12-month examination. No significant differences were found between subjects in the two groups with respect to implant survival rates and peri-implant bone loss, and patient satisfaction scores continued to be high. Although patient satisfaction and implant success were high during the 12- to 60-month period, the results should be interpreted with caution because of the high number of failing implants and patients lost to followup. More research is needed to study outcomes of treatment with immediately loaded mandibular implant overdentures.
- Published
- 2017
48. Fragment-Based Lead Discovery
- Author
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Ben Davis and Stephen D. Roughley
- Subjects
0301 basic medicine ,Library design ,010404 medicinal & biomolecular chemistry ,03 medical and health sciences ,030104 developmental biology ,Low affinity ,Fragment (logic) ,Drug discovery ,Computer science ,Fragment-based lead discovery ,Computational biology ,01 natural sciences ,0104 chemical sciences - Abstract
Since its inception in the late 1990s, fragment-based lead discovery (FBLD) has developed into a robust and generic approach for drug discovery. Two clinically approved drugs have been developed using the FBLD approach, and at least 30 FBLD-derived compounds are in various stages of clinical development. Based on the principle of the identification of small (and hence typically low affinity) ligands which make well-defined interactions with the receptor, and the evolution of these initial fragment hits into larger, more potent ligands that maintain these key interactions, FBLD has proven to be a reliable technique which is applicable to wide range of targets. In this chapter, we will discuss the philosophy and rationale underpinning the FBLD approach, theoretical and practical considerations of fragment library design, fragment screening and characterization, and the evolution of initial low molecular weight fragment hits into larger, potent molecules suitable for lead optimization and preclinical development. We will also discuss informative case histories, showing the challenges, pitfalls, and successful approaches, which have been applied to a number of therapeutically relevant targets.
- Published
- 2017
49. VER-246608, a novel pan-isoform ATP competitive inhibitor of pyruvate dehydrogenase kinase, disrupts Warburg metabolism and induces context-dependent cytostasis in cancer cells
- Author
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Anna Staniszewska, Lisa Baker, Jonathan D. Moore, James Murray, Patrick C. Mahon, Terence Shaw, Paul Brough, Alan Surgenor, Michael Wood, Ben Davis, Jalanie D’Alessandro, Natalia Matassova, and Macias Alba
- Subjects
Models, Molecular ,Pyruvate decarboxylation ,Pyruvate dehydrogenase lipoamide kinase isozyme 1 ,Pyruvate dehydrogenase kinase ,Nov3r ,Protein Serine-Threonine Kinases ,Pyruvate dehydrogenase phosphatase ,Biology ,Binding, Competitive ,chemistry.chemical_compound ,Adenosine Triphosphate ,Tumor Cells, Cultured ,Humans ,Neoplasm Invasiveness ,Glycolysis ,Enzyme Inhibitors ,Molecular Structure ,Pyruvate Dehydrogenase Acetyl-Transferring Kinase ,glycolysis ,Pyruvate dehydrogenase complex ,Cytostasis ,Isoenzymes ,Pyrimidines ,Oncology ,chemistry ,Biochemistry ,Benzamides ,Warburg metabolism ,K562 Cells ,Adenosine triphosphate ,Research Paper - Abstract
Pyruvate dehydrogenase kinase (PDK) is a pivotal enzyme in cellular energy metabolism that has previously been implicated in cancer through both RNAi based studies and clinical correlations with poor prognosis in several cancer types. Here, we report the discovery of a novel and selective ATP competitive pan-isoform inhibitor of PDK, VER-246608. Consistent with a PDK mediated MOA, VER-246608 increased pyruvate dehydrogenase complex (PDC) activity, oxygen consumption and attenuated glycolytic activity. However, these effects were only observed under D-glucose-depleted conditions and required almost complete ablation of PDC E1α subunit phosphorylation. VER-246608 was weakly anti-proliferative to cancer cells in standard culture media; however, depletion of either serum or combined D-glucose/L-glutamine resulted in enhanced cellular potency. Furthermore, this condition-selective cytostatic effect correlated with reduced intracellular pyruvate levels and an attenuated compensatory response involving deamination of L-alanine. In addition, VER-246608 was found to potentiate the activity of doxorubicin. In contrast, the lipoamide site inhibitor, Nov3r, demonstrated sub-maximal inhibition of PDK activity and no evidence of cellular activity. These studies suggest that PDK inhibition may be effective under the nutrient-depleted conditions found in the tumour microenvironment and that combination treatments should be explored to reveal the full potential of this therapeutic strategy.
- Published
- 2014
50. Differential lateralization of hippocampal connectivity reflects features of recent context and ongoing demands: An examination of immediate post-task activity
- Author
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Uri Hasson, James F. Hartzell, Nathan Cashdollar, Ben Davis, and Michael J. Tobia
- Subjects
Radiological and Ultrasound Technology ,Resting state fMRI ,Context (language use) ,Human brain ,Hippocampal formation ,Lateralization of brain function ,Task (project management) ,medicine.anatomical_structure ,Neurology ,Neuroimaging ,Laterality ,medicine ,Radiology, Nuclear Medicine and imaging ,Neurology (clinical) ,Anatomy ,Psychology ,Neuroscience - Abstract
Neuroimaging studies have shown that task demands affect connectivity patterns in the human brain not only during task performance but also during subsequent rest periods. Our goal was to determine whether ongoing connectivity patterns during rest contain information about both the current rest state, as well as the recently terminated task. Our experimental design consisted of two types of active tasks that were followed by two types of low-demand rest states. Using this design, we examined whether hippocampal functional connectivity during wakeful rest reflects both features of a recently terminated task and those of the current resting-state condition. We identified four types of networks: (i) one whose connectivity with the hippocampus was determined only by features of a recently terminated task, (ii) one whose connectivity was determined only by features of the current resting-state, (iii) one whose connectivity reflected aspects of both the recently terminated task and ongoing resting-state features, and (iv) one whose connectivity with the hippocampus was strong, but not affected by any external factor. The left and right hippocampi played distinct roles in these networks. These findings suggest that ongoing hippocampal connectivity networks mediate information integration across multiple temporal scales, with hippocampal laterality moderating these connectivity patterns. Hum Brain Mapp 36:519–537, 2015. © 2014 Wiley Periodicals, Inc.
- Published
- 2014
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