5,471 research outputs found
Gentrification and Vulnerability of Maine Fishing Communities
Maine hosts numerous small fishing villages that contribute greatly to the States economy and culture. The cumulative effects of state and federal regulation, stock depletion and other socio-economic trends threaten these communities. Drawing on ethnographic research and interviews, we examine how gentrification is affecting the vulnerability and resilience of fishing communities. This study has revealed gentrification to be a complex process, which is merely the most readily recognizable symptom of forces that are reshaping the post-industrial landscape. Fishing communities can no longer be thought of as discrete entities isolated from broad social and economic changes. Technology and new markets have unleashed fishing effort from its artisanal restraints, likewise they have enabled capital to expand beyond metropolitan barriers. Findings indicate that a rural restructuring has occurred and amenity migrants are being drawn to these communities. These people from away increase demand for services otherwise not provided and present new economic opportunities for community members and fishermen. However, as wealth migrates out of its metropolitan centers into these communities, it threatens to transform and displace productive economies with service economies. These trends may be beyond the capacity of fisheries management to account for, but policy makers should recognize their cumulative effects. The vulnerability framework readily provides a means of assessing fishing communities and the impact of gentrification on them. The characteristics of gentrification are unique for each community, though a few themes are prominent. Rather than being an entirely negative influence, gentrification can provide benefits for the community. Nevertheless, displacement of both people and the fishing industry may occur. The increased cost of living and process of gentrification is displacing many fishermen and community members from coastal property. Further conflicts arise when fishing operations and access to the waterfront is impeded. It is apparent that when facing the threat of displacement there is much that can be done at the state and municipal level in supporting access to the waterfront
Population Dynamics of the Sub-Arctic Copepod Calanus Finmarchicus in the Gulf of Maine: Demography and Mortality Estimation
Calanus finmarchicus is a widely distributed copepod species that dominants the zooplankton community in the Gulf of Maine. It is of particular interest in its role as a major food source for the endangered northern right whale and stocks of herring, mackerel and cod. More accurate coupled models to predict its distribution requires better life history models. However, due to the difficulty in estimating it, mortality is often used as a closure term in those models; the value is justified mathematically rather than ecologically. Instantaneous mortality is difficult to measure, but the Vertical Life Table method (VLT) has gained some acceptance as an effective estimation technique. Calculations are made using the stage structure of the population and development rates. The VLT mortality estimations are heavily dependent upon development rates determined from temperature dependent functions and several assumptions. The limitations imposed by the VLT and inadvertent violations of assumptions prevented a spatial analysis of mortality. However, a new technique is presented to provide a much more explicit array of instantaneous mortalities that vary with season, stage and distance from shore. The Structured Population Molting rate method uses in situ incubations to directly observe the progressing stage structure and calculate the molting rates. The observed C. finmarchicus demography suggests that there is size selective predation mortality corresponding with bathymetry. Near shore regions host various visual predators of late stage C. finmarchicus and lack a depth refuge through vertical migration. These factors could explain the paucity of later stages when compared to offshore regions, but an alternative hypothesis suggests that the Maine coastal currents are responsible for transporting C. finmarchicus to the deep off shore basins where they are found in great abundance
CONDITIONAL FORECASTING FOR THE U.S. DAIRY PRICE COMPLEX WITH A BAYESIAN VECTOR AUTOREGRESSIVE MODEL
A dynamic Bayesian Vector Autoregressive model of the U.S. dairy price complex is estimated based on the Normal-Wishart distribution. The Gibbs sample technique is use with the Normal-Wishart distribution to provide conditional forecasts on the future time-paths of the model variables. The conditional forecasts for key prices are examined. Confidence intervals are calculated for the conditional forecasts.Demand and Price Analysis,
Holocene lake sediment core sequences from Lochnagar, Cairngorm Mts., Scotland - UK final report for CHILL-10,000
The CHILL 10,000 research objective at Lochnagar is to examine proxy data for temperature
and climate conditions. Changes in lake sediment stratigraphical data can be used to reconstruct
past conditions. These proxies include organic and minerogenic matter as a bulk proxy for
catchment and within-lake productivity, chironomids as a proxy for air temperature, diatoms as
an indicator for lake water pH, pollen as an indicator of catchment vegetation and finally
biomarkers to help determine changes in proportions of organic source material within the lake
mud
Enhancements in Mass Transfer for Carbon Capture Solvents Part I: Homogeneous Catalyst
The novel small molecule carbonic anhydrase (CA) mimic [CoIII(Salphen-COO−)Cl]HNEt3 (1), was synthesized as an additive for increasing CO2 absorption rates in amine-based post-combustion carbon capture processes (CCS), and its efficacy was verified. 1 was designed for use in a kinetically slow but thermally stable blended solvent, containing the primary amines 1-amino-2-propanol (A2P) and 2-amino-2-methyl-1-propanol (AMP). Together, the A2P/AMP solvent and 1 reduce the overall energy penalty associated with CO2 capture from coal-derived flue gas, relative to the baseline solvent MEA. 1 is also effective at increasing absorption kinetics of kinetically fast solvents, such as MEA, which can reduce capital costs by requiring a smaller absorber tower. The transition from catalyst testing under idealized laboratory conditions, to process relevant lab- and bench-scale testing adds many additional variables that are not well understood and rarely discussed. The stepwise testing of both 1 and the novel A2P/AMP solvent blend is described through a transition process that identifies many of these process and evaluation challenges not often addressed when designing a chemical or catalytic additive for industrial CCS systems, where consideration of solvent chemistry is typically the primary goal
High-resolution Near-Infrared Images and Models of the Circumstellar Disk in HH 30
We present Hubble Space Telescope (HST) Near-Infrared Camera and Multi-object
Spectrometer (NICMOS) observations of the reflection nebulosity associated with
the T Tauri star HH 30. The images show the scattered light pattern
characteristic of a highly inclined, optically thick disk with a prominent
dustlane whose width decreases with increasing wavelength. The reflected
nebulosity exhibits a lateral asymmetry in the upper lobe on the opposite side
to that reported in previously published Wide Field Planetary Camera 2 (WFPC2)
images. The radiation transfer model which most closely reproduces the data has
a flared accretion disk with dust grains larger than standard interstellar
medium grains by a factor of approximately 2.1. A single hotspot on the stellar
surface provides the necessary asymmetry to fit the images and is consistent
with previous modeling of the light curve and images. Photometric analysis
results in an estimated extinction of Av>~80; however, since the photometry
measures only scattered light rather than direct stellar flux, this a lower
limit. The radiative transfer models require an extinction of Av = 7,900.Comment: Accepted for publication in Ap.
GRB 070201: A possible Soft Gamma Ray Repeater in M31
The gamma-ray burst (GRB) 070201 was a bright short-duration hard-spectrum
GRB detected by the Inter-Planetary Network (IPN). Its error quadrilateral,
which has an area of 0.124 sq. deg, intersects some prominent spiral arms of
the nearby M31 (Andromeda) galaxy. Given the properties of this GRB, along with
the fact that LIGO data argues against a compact binary merger origin in M31,
this GRB is an excellent candidate for an extragalactic Soft Gamma-ray Repeater
(SGR) giant flare, with energy of 1.4x10^45 erg. Analysis of ROTSE-IIIb visible
light observations of M31, taken 10.6 hours after the burst and covering 42% of
the GRB error region, did not reveal any optical transient down to a limiting
magnitude of 17.1. We inspected archival and proprietary XMM-Newton X-ray
observations of the intersection of the GRB error quadrilateral and M31,
obtained about four weeks prior to the outburst, in order to look for periodic
variable X-ray sources. No SGR or Anomalous X-ray Pulsar (AXP) candidates
(periods in range 1 to 20 s) were detected. We discuss the possibility of
detecting extragalactic SGRs/AXPs by identifying their periodic X-ray light
curves. Our simulations suggest that the probability of detecting the periodic
X-ray signal of one of the known Galactic SGRs/AXPs, if placed in M31, is about
10% (50%), using 50 ks (2 Ms) XMM-Newton exposures.Comment: 7 pages, submitted to ApJ (Fig. 2 resolution reduced
SGR 1806-20 about two years after the giant flare: Suzaku, XMM-Newton and INTEGRAL observations
In December 2004, the soft gamma-ray repeater SGR 1806-20 emitted the most
powerful giant flare ever observed. This probably involved a large-scale
rearrangement of the magnetosphere leading to observable variations in the
properties of its X-ray emission. Here we present the results of the first
Suzaku observation of SGR 1806-20, together with almost simultaneous
observations with XMM-Newton and INTEGRAL. The source seems to have reached a
state characterized by a flux close to the pre-flare level and by a relatively
soft spectrum. Despite this, SGR 1806-20 remained quite active also after the
giant flare, allowing us to study several short bursts observed by Suzaku in
the 1-100 keV range. We discuss the broad-band spectral properties of SGR
1806-20, covering both persistent and bursting emission, in the context of the
magnetar model, and consider its recent theoretical developments.Comment: Accepted for publication in Astronomy & Astrophysic
Helioseismology of Sunspots: A Case Study of NOAA Region 9787
Various methods of helioseismology are used to study the subsurface
properties of the sunspot in NOAA Active Region 9787. This sunspot was chosen
because it is axisymmetric, shows little evolution during 20-28 January 2002,
and was observed continuously by the MDI/SOHO instrument. (...) Wave travel
times and mode frequencies are affected by the sunspot. In most cases, wave
packets that propagate through the sunspot have reduced travel times. At short
travel distances, however, the sign of the travel-time shifts appears to depend
sensitively on how the data are processed and, in particular, on filtering in
frequency-wavenumber space. We carry out two linear inversions for wave speed:
one using travel-times and phase-speed filters and the other one using mode
frequencies from ring analysis. These two inversions give subsurface wave-speed
profiles with opposite signs and different amplitudes. (...) From this study of
AR9787, we conclude that we are currently unable to provide a unified
description of the subsurface structure and dynamics of the sunspot.Comment: 28 pages, 18 figure
Precision Astrometry of a Sample of Speckle Binaries and Multiples with the Adaptive Optics Facilities at the Hale and Keck II Telescopes
Using the adaptive optics facilities at the 200-in Hale and 10-m Keck II, we
observed in the near infrared a sample of 12 binary and multiple stars and one
open cluster. We used the near diffraction limited images of these systems to
measure the relative separations and position angles between their components.
In this paper, we investigate and correct for the influence of the differential
chromatic refraction and chip distortions on our relative astrometric
measurements. Over one night, we achieve an astrometric precision typically
well below 1 miliarcsecond and occasionally as small as 40 microarcseconds.
Such a precision is in principle sufficient to astrometrically detect planetary
mass objects around the components of nearby binary and multiple stars. Since
we have not had sufficiently large data sets for the observed sample of stars
to detect planets, we provide the limits to planetary mass objects based on the
obtained astrometric precision.Comment: 18 pages, 8 figures, 9 tables, to appear in MNRA
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