Navigation of brain networks

Understanding the mechanisms of neural communication in large-scale brain networks remains a major goal in neuroscience. We investigated whether navigation is a parsimonious routing model for connectomics. Navigating a network involves progressing to the next node that is closest in distance to a desired destination. We developed a measure to quantify navigation efficiency and found that connectomes in a range of mammalian species (human, mouse and macaque) can be successfully navigated with near-optimal efficiency (>80% of optimal efficiency for typical connection densities). Rewiring network topology or repositioning network nodes resulted in 45%-60% reductions in navigation performance. Specifically, we found that brain networks cannot be progressively rewired (randomized or clusterized) to result in topologies with significantly improved navigation performance. Navigation was also found to: i) promote a resource-efficient distribution of the information traffic load, potentially relieving communication bottlenecks; and, ii) explain significant variation in functional connectivity. Unlike prevalently studied communication strategies in connectomics, navigation does not mandate biologically unrealistic assumptions about global knowledge of network topology. We conclude that the wiring and spatial embedding of brain networks is conducive to effective decentralized communication. Graph-theoretic studies of the connectome should consider measures of network efficiency and centrality that are consistent with decentralized models of neural communication

Park Supply and Demand Part II: Downtown Silver Spring

Final project for URSP688M: Planning Technologies (Spring 2018). University of Maryland, College Park.As Downtown Silver Spring continues to urbanize, it becomes increasingly important to provide its residents and workforce with adequate recreational space. In conjunction with the the Maryland- National Capital Park and Planning Commission (M-NCPPC), this report investigates which areas of Downtown Silver Spring are adequately served by parks and those that lack robust access to these facilities. Using an ArcGIS-based model that combines pedestrian and bicycle access, population demographics, and data on local parks, our model assesses the degree to which Downtown Silver Spring’s residents and workforce have adequate access to parks. The report begins with a literature review on the value of parks and summarizes ways that supply and demand for recreational space have been geospatially analyzed. The second section details the methodology used to create the supply and demand model. The results section offers an analysis of gaps in park supply and demand, combining findings with population and workforce data. The report concludes with a list of recommendations to assist M-NCPPC in planning for parks in Downtown Silver Spring. Part I: http://hdl.handle.net/1903/21104Downtown Silver Sprin

Developing Innovation Village, Baltimore

Final project for URSP688L: Planning Technologies (Fall 2016). University of Maryland, College Park.We researched the Innovation Village in Baltimore City to better understand which areas are most suitable for development, how accessible public transportation is within the area, the extent of community resources available, and the current employment environment. We used housing vacancy, property values, and access to rail transit to develop a suitability analysis for development. By creating a map of 1/4-mile transit buffers, we were able to determine pedestrian accessibility to different parts of the Innovation Village resources. With maps showing the transit, employment and property value context, we hope to aid in the decision-making process for economic development, while encouraging strategies that encourage hiring programs for current residents and preventing displacement.The Mount Royal Community Development Corporation (MRCDC

Reconfigurable quantum metamaterials

By coupling controllable quantum systems into larger structures we introduce the concept of a quantum metamaterial. Conventional meta-materials represent one of the most important frontiers in optical design, with applications in diverse fields ranging from medicine to aerospace. Up until now however, metamaterials have themselves been classical structures and interact only with the classical properties of light. Here we describe a class of dynamic metamaterials, based on the quantum properties of coupled atom-cavity arrays, which are intrinsically lossless, reconfigurable, and operate fundamentally at the quantum level. We show how this new class of metamaterial could be used to create a reconfigurable quantum superlens possessing a negative index gradient for single photon imaging. With the inherent features of quantum superposition and entanglement of metamaterial properties, this new class of dynamic quantum metamaterial, opens a new vista for quantum science and technology.Comment: 16 pages, 8 figure

Methicillin-resistant Staphylococci in Companion Animals

We determined the molecular characteristics of methicillin-resistant staphylococci from animals and staff at a small animal and equine hospital. Methicillin-resistant Staphylococcus aureus (MRSA) identical to human EMRSA-15 was found in dogs and hospital staff. In contrast, 5 distinct MRSA strains were isolated from horses but not from hospital staff

Patient-centric trials for therapeutic development in precision oncology

An enhanced understanding of the molecular pathology of disease gained from genomic studies is facilitating the development of treatments that target discrete molecular subclasses of tumours. Considerable associated challenges include how to advance and implement targeted drug-development strategies. Precision medicine centres on delivering the most appropriate therapy to a patient on the basis of clinical and molecular features of their disease. The development of therapeutic agents that target molecular mechanisms is driving innovation in clinical-trial strategies. Although progress has been made, modifications to existing core paradigms in oncology drug development will be required to realize fully the promise of precision medicine

HIV outbreaks among people who inject drugs in Europe, North America and Israel

During 2011–16, HIV outbreaks occurred among people who inject drugs (PWID) in Canada (southeastern Saskatchewan), Greece (Athens), Ireland (Dublin), Israel (Tel Aviv), Luxembourg, Romania (Bucharest), Scotland (Glasgow), and USA (Scott County, Indiana). Factors common to many of these outbreaks included community economic problems, homelessness, and changes in drug injection patterns. The outbreaks differed in size (from under 100 to over 1000 newly reported HIV cases among PWID) and in the extent to which combined prevention had been implemented before, during, and after the outbreaks. Countries need to ensure high coverage of HIV prevention services and coverage higher than the current UNAIDS recommendation might be needed in areas in which short acting drugs are injected. In addition, monitoring of PWID with special attention for changing drug use patterns, risk behaviours, and susceptible subgroups (eg, PWID experiencing homelessness) needs to be in place to prevent or rapidly detect and contain new HIV outbreaks