Methods for Generating Complex Networks with Selected Structural Properties for Simulations: A Review and Tutorial for Neuroscientists

Many simulations of networks in computational neuroscience assume completely homogenous random networks of the Erdös–Rényi type, or regular networks, despite it being recognized for some time that anatomical brain networks are more complex in their connectivity and can, for example, exhibit the “scale-free” and “small-world” properties. We review the most well known algorithms for constructing networks with given non-homogeneous statistical properties and provide simple pseudo-code for reproducing such networks in software simulations. We also review some useful mathematical results and approximations associated with the statistics that describe these network models, including degree distribution, average path length, and clustering coefficient. We demonstrate how such results can be used as partial verification and validation of implementations. Finally, we discuss a sometimes overlooked modeling choice that can be crucially important for the properties of simulated networks: that of network directedness. The most well known network algorithms produce undirected networks, and we emphasize this point by highlighting how simple adaptations can instead produce directed networks

Prescription for Progress: NN/LM New England Region Subcontractor Outreach Activities

The mission of the National Network of Libraries of Medicine (NN/LM®) is to advance the progress of medicine and improve the public health by providing all U.S. health professionals equal access to biomedical information and by improving the public\u27s access to information to enable them to make informed decisions about their health. The Program is coordinated by the National Library of Medicine and carried out through a nationwide network of health science libraries, public Libraries, and information centers. Under contract with NLM, Regional Medical Libraries continue their efforts strengthen the Network to reach under served health professionals in rural and inner city areas, public health professionals, and special populations. NN/LM members work with a variety of intermediaries, including health care providers, public health professionals, public librarians, educators, community organizations, health advocacy groups, faith-based organizations, and self-help groups, to reach members of the public. The Regional Medical Library for the New England Region is the Lamar Soutter Library at the University of Massachusetts Medical School in Worcester, Massachusetts. The New England Region of 516 members includes 16 Resource Libraries, over 360 hospital and academic libraries, and over 100 public libraries

Covalent bond shortening and distortion induced by pressurization of thorium, uranium, and neptunium tetrakis aryloxides

Covalency involving the 5f orbitals is regularly invoked to explain the reactivity, structure and spectroscopic properties of the actinides, but the ionic versus covalent nature of metal-ligand bonding in actinide complexes remains controversial. The tetrakis 2,6-di-tert-butylphenoxide complexes of Th, U and Np form an isostructural series of crystal structures containing approximately tetrahedral MO(4) cores. We show that up to 3 GPa the Th and U crystal structures show negative linear compressibility as the OMO angles distort. At 3 GPa the angles snap back to their original values, reverting to a tetrahedral geometry with an abrupt shortening of the M-O distances by up to 0.1 Å. The Np complex shows similar but smaller effects, transforming above 2.4 GPa. Electronic structure calculations associate the M-O bond shortening with a change in covalency resulting from increased contributions to the M-O bonding by the metal 6d and 5f orbitals, the combination promoting MO(4) flexibility at little cost in energy

On thermodynamic modeling and the role of the second law of thermodynamics in geophysics

The article contains a brief review of elements of thermodynamic modeling in theoretical geophysics. We motivate the existence of the second law of thermodynamics in macroscopic theoretical physics and demonstrate its evaluation. In particular we show its consequences in the construction of constitutive laws for a two-component poroelastic medium. This construction is also related to microstructural properties verified by means of the second law

Correlating wear with the lubricant properties of heavy-duty diesel engine oils

Wear volumes were correlated with the lubricant properties of 11 used, heavy duty engine oil samples. The most important oil property in predicting wear volume is Total Acid Number, TAN. Here, the TAN value may be indicating ZDDP in its oxidised form and unable to participate in corrosive-abrasive wear. Low wear also correlates with mean soot particle size/circularity, which further suggests the abrasive aspect of this mechanism. Finally, low wear correlates with high calcium concentration in the fresh oil. This suggests a new wear reduction mechanism in which calcium from the detergent replenishes the iron within the ZDDP antiwear film

The 3rd Global Summit of Research Institutes for Disaster Risk Reduction: Expanding the Platform for Bridging Science and Policy Making

The Global Alliance of Disaster Research Institutes held its 3rd Global Summit of Research Institutes for Disaster Risk Reduction at the Disaster Prevention Research Institute, Kyoto University, Japan, 19–21 March, 2017. The Global Alliance seeks to contribute to enhancing disaster risk reduction (DRR) and disaster resilience through the collaboration of research organizations around the world. The summit aim was to expand the platform for bridging science and policy making by evaluating the evidence base needed to meet the expected outcomes and actions of the Sendai Framework for Disaster Risk Reduction 2015–2030 and its Science and Technology Roadmap. The summit reflected the international nature of collaborative research and action. A pre-conference questionnaire filled out by Global Alliance members identified 323 research projects that are indicative of current research. These were categorized to support seven parallel discussion sessions related to the Sendai Framework priorities for action. Four discussion sessions focused on research that aims to deepen the understanding of disaster risks. Three cross-cutting sessions focused on research that is aimed at the priorities for action on governance, resilience, and recovery. Discussion summaries were presented in plenary sessions in support of outcomes for widely enhancing the science and policy of DRR

A simple tool for estimating throughfall nitrogen deposition in forests of western North America using lichens

Anthropogenic nitrogen (N) deposition has had substantial impacts on forests of North America. Managers seek to monitor deposition to identify areas of concern and establish critical loads, which define the amount of deposition that can be tolerated by ecosystems without causing substantial harm. We present a new monitoring approach that estimates throughfall inorganic N deposition from N concentration in lichens collected on site. Across 84 study sites in western North America with measured throughfall, a single regression model effectively estimated N deposition from lichen N concentration with an R² of 0.58 and could be improved with the addition of climate covariates including precipitation seasonality and temperature in the wettest quarter to an R² of 0.74. By restricting the model to the more intensively sampled region including Oregon, Washington, and California, the R² increased to 0.77. Because lichens are readily available, analysis is cost-effective, and accuracy is unaffected by mountainous terrain, this method allows development of deposition estimates at sites across broad spatial and topographic scales. Our approach can allow land managers to identify areas at risk of N critical load exceedance, which can be used for planning and management of air pollution impacts.This is the publisher’s final pdf. The published article is copyrighted by Elsevier and can be found at: http://www.elsevier.com/Keywords: Air quality, Critical loads, Nitrogen deposition, Lichens, Throughfal

A CD317/tetherin–RICH2 complex plays a critical role in the organization of the subapical actin cytoskeleton in polarized epithelial cells

CD317/tetherin is a lipid raft–associated integral membrane protein with a novel topology. It has a short N-terminal cytosolic domain, a conventional transmembrane domain, and a C-terminal glycosyl-phosphatidylinositol anchor. We now show that CD317 is expressed at the apical surface of polarized epithelial cells, where it interacts indirectly with the underlying actin cytoskeleton. CD317 is linked to the apical actin network via the proteins RICH2, EBP50, and ezrin. Knocking down expression of either CD317 or RICH2 gives rise to the same phenotype: a loss of the apical actin network with concomitant loss of apical microvilli, an increase in actin bundles at the basal surface, and a reduction in cell height without any loss of tight junctions, transepithelial resistance, or the polarized targeting of apical and basolateral membrane proteins. Thus, CD317 provides a physical link between lipid rafts and the apical actin network in polarized epithelial cells and is crucial for the maintenance of microvilli in such cells