Outport adaptations: Social indicators through Newfoundland\u27s Cod crisis

The 1992 moratorium on fishing for Northern Cod marked a symbolic end to the way of life that had sustained Newfoundland\u27s out ports for hundreds of years. It also marked the completion of an ecological regime shift, from an ocean ecosystem dominated by cod and other predatory ground fish, to one in which such fish are comparatively scarce, and lower-trophic-level invertebrates more common. We examine patterns of change seen in large-scale social indicators, which reflect the smaller-scale adaptations of individuals and communities during this ecological shift. Trends in population, migration, age, unemployment and dependency suggest declining conditions in rural Newfoundland over the years of fisheries troubles. The 1992 crisis accelerated previous trends, but did not produce great discontinuities. Some trends date instead to the late-1980s resource-depletion phase that ended the glory years of Newfoundland\u27s ground fish boom. Government interventions meant to soften the economic impact of the 1992 crisis also blunted its social impacts, effectively postponing or distributing these over a number of subsequent years. Out port society is adapting to shifts in the regulatory and global-market environment, as well as changing marine ecology. Adaptive strategies include new investments in invertebrate fisheries, changes in education and migration, and continuing reliance on the informal economy

Local light-ray rotation

We present a sheet structure that rotates the local ray direction through an arbitrary angle around the sheet normal. The sheet structure consists of two parallel Dove-prism sheets, each of which flips one component of the local direction of transmitted light rays. Together, the two sheets rotate transmitted light rays around the sheet normal. We show that the direction under which a point light source is seen is given by a Mobius transform. We illustrate some of the properties with movies calculated by ray-tracing software.Comment: 9 pages, 6 figure

Metamaterials for light rays: ray optics without wave-optical analog in the ray-optics limit

Volumes of sub-wavelength electromagnetic elements can act like homogeneous materials: metamaterials. In analogy, sheets of optical elements such as prisms can act ray-optically like homogeneous sheet materials. In this sense, such sheets can be considered to be metamaterials for light rays (METATOYs). METATOYs realize new and unusual transformations of the directions of transmitted light rays. We study here, in the ray-optics and scalar-wave limits, the wave-optical analog of such transformations, and we show that such an analog does not always exist. Perhaps, this is the reason why many of the ray-optical possibilities offered by METATOYs have never before been considered.Comment: 10 pages, 3 figures, references update

Public knowledge about polar regions increases while concerns remain unchanged

The authors of this brief conduct the first comparative analysis of the polar questions that were part of the National Opinion Research Center\u27s 2006 and 2010 General Social Survey. Developed by scientists at the National Science Foundation\u27s Office of Polar Programs, these questions covered topics such as climate change, melting ice and rising sea levels, and species extinction. The authors report that the public\u27s knowledge about the north and south polar regions significantly improved between 2006 and 2010--before and after the International Polar Year. In addition, respondents who know more about science in general, and polar facts specifically, tend to be more concerned about polar changes. More knowledgeable respondents also tend to favor reserving the Antarctic for science, rather than opening it for commercial development

Quantifying temporal and spatial variations in sediment, nitrogen and phosphorus transport in stream inflows to a large eutrophic lake

High-frequency sampling of two major stream inflows to a large eutrophic lake (Lake Rotorua, New Zealand) was conducted to measure inputs of total suspended sediment (TSS), and fractions of nitrogen and phosphorus (P). A total of 17 rain events were sampled, including three during which both streams were simultaneously monitored to quantify how concentration–discharge (Q) relationships varied between catchments during similar hydrological conditions. Dissolved inorganic nitrogen (DIN) concentrations declined slightly during events, reflecting dilution of groundwater inputs by rainfall, whereas dissolved inorganic P (PO₄–P) concentrations were variable and unrelated to Q, suggesting dynamic sorptive behaviour. Event loads of total nitrogen (TN) were predominantly DIN, which is available for immediate uptake by primary producers, whereas total phosphorus (TP) loads predominantly comprised particulate P (less labile). Positive correlations between Q and concentrations of TP (and to a lesser extent TN) reflected increased particulate nutrient concentrations at high flows. Consequently, load estimates based on hourly Q during storm events and concentrations of routine monthly samples (mostly base flow) under-estimated TN and TP loads by an average of 19% and 40% respectively. Hysteresis with Q was commonly observed and inclusion of hydrological variables that reflect Q history in regression models improved predictions of TN and TP concentrations. Lorenz curves describing the proportions of cumulative load versus cumulative time quantified temporal inequality in loading. In the two study streams, 50% of estimated two-year loads of TN, TP and TSS were transported in 202–207, 76–126 and 1–8 days respectively. This study quantifies how hydrological and landscape factors can interact to influence pollutant flux at the catchment scale and highlights the importance of including storm transfers in lake loading estimates

Search for L5 Earth Trojans with DECam

Most of the major planets in the Solar system support populations of co-orbiting bodies, known as Trojans, at their L4 and L5 Lagrange points. In contrast, Earth has only one known co-orbiting companion. This paper presents the results from a search for Earth Trojans (ETs) using the DECam instrument on the Blanco Telescope at CTIO. This search found no additional Trojans in spite of greater coverage compared to previous surveys of the L5 point. Therefore, the main result of this work is to place the most stringent constraints to date on the population of ETs. These constraints depend on assumptions regarding the underlying population properties, especially the slope of the magnitude distribution (which in turn depends on the size and albedo distributions of the objects). For standard assumptions, we calculate upper limits to a 90 per cent confidence limit on the L5 population of N_(ET) < 1 for magnitude H < 15.5, N_(ET) = 60–85 for H < 19.7, and N_(ET) = 97 for H = 20.4. This latter magnitude limit corresponds to Trojans ∼300 m in size for albedo 0.15. At H = 19.7, these upper limits are consistent with previous L4 ET constraints and significantly improve L5 constraints

Electric field induced charge noise in doped silicon: ionization of phosphorus donors

We report low frequency charge noise measurement on silicon substrates with different phosphorus doping densities. The measurements are performed with aluminum single electron transistors (SETs) at millikelvin temperatures where the substrates are in the insulating regime. By measuring the SET Coulomb oscillations, we find a gate voltage dependent charge noise on the more heavily doped substrate. This charge noise, which is seen to have a 1/f spectrum, is attributed to the electric field induced tunneling of electrons from their phosphorus donor potentials.Comment: 4 page, 3 figure

Impacts of energy efficiency retrofitting measures on indoor PM concentrations across different income groups in England: a modelling study

As part of an effort to reduce carbon emissions in the UK, policies encouraging the energy-efficient retrofit of domestic properties are being implemented. Typical retrofits, including installation of insulation and double glazing can cause tightening of the building envelope which may affect indoor air quality (IAQ) impacting occupant health. Using the example of PM (an airborne pollutant with known health impacts), this study considers the influence of energy-efficient retrofits on indoor PM concentrations in domestic properties both above and below the low-income threshold (LIT) for a range of tenancies across England. Simulations using EnergyPlus and its integrated Generic Contaminant model are employed to predict indoor PM exposures from both indoor and outdoor sources in building archetypes representative of (i) the existing housing stock and (ii) a retrofitted English housing stock. The exposures of occupants for buildings occupied by groups above and below the LIT are then estimated under current conditions and following retrofits. One-way ANOVA tests were applied to clarify results and investigate differences between the various income and tenure groups. Results indicate that all tenures below the LIT experience greater indoor PM concentrations than those above, suggesting possible social inequalities driven by housing, leading to consequences for health