1,926 research outputs found

    Everyone should be able to choose how they get around : How Topeka, Kansas, passed a complete streets resolution

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    BACKGROUND: Regular physical activity can help prevent chronic diseases, yet only half of US adults meet national physical activity guidelines. One barrier to physical activity is a lack of safe places to be active, such as bike paths and sidewalks. Complete Streets, streets designed to enable safe access for all users, can help provide safe places for activity. COMMUNITY CONTEXT: This community case study presents results from interviews with residents and policymakers of Topeka, Kansas, who played an integral role in the passage of a Complete Streets resolution in 2009. It describes community engagement processes used to include stakeholders, assess existing roads and sidewalks, and communicate with the public and decision-makers. METHODS: Key informant interviews were conducted with city council members and members of Heartland Healthy Neighborhoods in Topeka to learn how they introduced a Complete Streets resolution and the steps they took to ensure its successful passage in the City Council. Interviews were recorded, transcribed, and analyzed by using focused-coding qualitative analysis. OUTCOME: Results included lessons learned from the process of passing the Complete Streets resolution and advice from participants for other communities interested in creating Complete Streets in their communities. INTERPRETATION: Lessons learned can apply to other communities pursuing Complete Streets. Examples include clearly defining Complete Streets; educating the public, advocates, and decision-makers about Complete Streets and how this program enhances a community; building a strong and diverse network of supporters; and using stories and examples from other communities with Complete Streets to build a convincing case

    Bioaccumulation surveillance in Milford Haven Waterway

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    Biomonitoring of contaminants (metals, organotins, PAHs, PCBs) was carried out along the Milford Haven Waterway (MHW) and at a reference site in the Tywi Estuary during 2007-2008. The species used as bioindicators encompass a variety of uptake routes - Fucus vesiculosus (dissolved contaminants); Littorina littorea (grazer); Mytilus edulis and Cerastoderma edule (suspension feeders); and Nereis diversicolor (omnivore which often reflects contaminants in sediment). Differences in feeding strategy and habitat preference have subtle implications for bioaccumulation trends though, with few exceptions, contaminant body burdens in Milford Haven (MH) were higher than those at the Tywi reference site, reflecting inputs. Elevated concentrations of metals were occasionally observed at individual MH sites, whilst As and Se (molluscs and seaweed) were, for much of MHW, consistently at the higher end of the UK range. However, for the majority of metals, distributions in MH biota were not exceptional by UK standards. Several metal-species combinations indicated increases in bioavailability at upstream sites, which may reflect the influence of geogenic or other land-based sources – perhaps enhanced by lower salinity (greater proportions of more bioavailable forms). TBT levels in MH mussels were below OSPAR toxicity thresholds and in the Tywi were close to zero. Phenyltins were not accumulated appreciably in Mytilus, whereas some Nereis populations may have been subjected to localized (historical) sources. PAHs in Nereis tended to be evenly distributed across most sites, but with somewhat higher values at Dale for acenaphthene, fluoranthene, pyrene, benzo(a)anthracene and chrysene; naphthalenes tended to be enriched further upstream in the mid-upper Haven (a pattern seen in mussels for most PAHs). Whilst concentrations in MH mussels were mostly above reference site and OSPAR backgrounds, it is unlikely that ecotoxicological guidelines would be exceeded. PCBs in mussels were between upper and lower OSPAR guidelines and were unusual in their distribution in that highest levels occurred at the mouth of MH. Condition indices (CI) of bivalves (mussels and cockles) were highest at the Tywi reference site and at the seaward end of MH, decreasing upstream along the Waterway. There were a number of significant (negative) relationships between CI and body burdens and multivariate analysis indicated that a combination of contaminants could influence the pattern in condition (and sub-lethal responses such as MT and TOSC) across sites. Cause and effect needs to be tested more rigorously in future assessments

    Motion for Leave to File and Brief of East Tennessee Valley Landowner\u27s Association, \u3cem\u3eAmicus Curiae\u3c/em\u3e, on behalf of Respondents, \u3cem\u3eTVA v. Hill\u3c/em\u3e, No. 76-1701

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    Brief for the respondents in the case of Tennessee Valley Authority v. Hiram G. Hill Jr., et al., heard by the United States Supreme Court in the October Term of 1977

    Effects of circadian rhythm phase alteration on physiological and psychological variables: Implications to pilot performance (including a partially annotated bibliography)

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    The effects of environmental synchronizers upon circadian rhythmic stability in man and the deleterious alterations in performance and which result from changes in this stability are points of interest in a review of selected literature published between 1972 and 1980. A total of 2,084 references relevant to pilot performance and circadian phase alteration are cited and arranged in the following categories: (1) human performance, with focus on the effects of sleep loss or disturbance and fatigue; (2) phase shift in which ground based light/dark alteration and transmeridian flight studies are discussed; (3) shiftwork; (4)internal desynchronization which includes the effect of evironmental factors on rhythmic stability, and of rhythm disturbances on sleep and psychopathology; (5) chronotherapy, the application of methods to ameliorate desynchronization symptomatology; and (6) biorythm theory, in which the birthdate based biorythm method for predicting aircraft accident susceptability is critically analyzed. Annotations are provided for most citations

    Reduced-intensity conditioning permits a significant graft vs leukemia (GvL) effect for acute leukemia

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    Conversion of Aniline to Azobenzene at Functionalized Carbon Nanotubes: A Possible Case of a Nanodimensional Reaction

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    Aniline is oxidized to nitrosobenzene as the initial product, which undergoes further oxidation to nitrobenzene. The nitrosobenzene formation is catalyzed by functionalized multiwalled carbon nanotubes (CNT) followed by a coupling reaction between nitrosobenzene and aniline to produce azobenzene. This coupling requires close proximity of the reactants. It proceeds rapidly resulting in the UV-VIS absorption spectrum showing maxima at 327 nm and 425 nm. The nitrosobenzene yield in the presence of CNTs is controlled by the amount present in the medium. As the reaction is not catalyzed by unfunctionalized CNTs or graphitic particles, the uniqueness of the functionalized multiwalled CNTs in this catalysis suggests a nanodimensional reaction pathway

    Spatiotemporal Multiplexed Rydberg Receiver

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    Rydberg states of alkali atoms, where the outer valence electron is excited to high principal quantum numbers, have large electric dipole moments allowing them to be used as sensitive, wideband, electric field sensors. These sensors use electromagnetically induced transparency (EIT) to measure incident electric fields. The characteristic timescale necessary to establish EIT determines the effective speed at which the atoms respond to time-varying RF radiation. Previous studies have predicted that this EIT relaxation rate causes a performance roll-off in EIT-based sensors beginning at a less than 10 MHz RF data symbol rate. Here, we propose an architecture for increasing the response speed of Rydberg sensors to greater than 100 MHz, through spatio-temporal multiplexing (STM) of the probe laser. We present experimental results validating the architecture's temporal multiplexing component using a pulsed laser. We benchmark a numerical model of the sensor to this experimental data and use the model to predict the STM sensor's performance as an RF communications receiver. For an on-off keyed (OOK) waveform, we use the numerical model to predict bit-error-ratios (BERs) as a function of RF power and data rates demonstrating feasibility of error free communications up to 100 Mbps with an STM Rydberg sensor.Comment: 7 pages, 7 figure
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