300 research outputs found
PARTICIPATION DECISIONS, ANGLER WELFARE, AND THE REGIONAL ECONOMIC IMPACT OF SPORTFISHING
We link a stochastic binary choice model of individual decisions to participate in the marine sport fisheries in Cook Inlet, Alaska, with a simulation- based sample enumeration procedure for aggregating estimates of individual angler welfare and a regionally adjusted zip code-level input-output model of regional economic activity. The result is a behaviorally based model for predicting changes in angler welfare and regional economic activity occasioned by changes in the demand for sportfishing that arise from changes in trip costs or the expected number, size, or mix of species caught. The advantages of this approach are that: changes in angler participation are determined by variables that are observable, predictable, or subject to management control; participation reflects declining marginal utility, and substitution and complementary effects across trip attributes; estimates of changes in aggregate angler welfare and changes in regional economic impacts are derived from changes in individual participation probabilities.Resource /Energy Economics and Policy,
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Alaskaâs Sablefish Fishery
Alaska is the worldâs principal supplier of Sablefish Anoplopoma fimbria a buttery-flavored whitefish greatly prized in Japan. Sablefish are distributed from Baja California to western Japan but the majority of commercial catches are from the Gulf of Alaska and the Aleutian Islands off Alaska. Landings volume and value of this long-lived demersal fish are comparable to those of the better-known Pacific Halibut Hippoglossus stenolepis. Like Pacific Halibut, Alaska region catches of Sablefish are managed under an Individual Fishing Quota (IFQ) program implemented in 1995. We present a simultaneous equation market model for Sablefish and use the model to examine linkages between landings volume and exvessel prices and revenues including the sensitivity of Alaska exvessel price and revenue to changes in landings, to changes resulting from the implementation of IFQs and to changes in the Japanese economy. Model simulations indicate that markets could absorb substantially more Sablefish than can be sustainably harvested from the current stock of Alaska region Sablefish. However, sluggishness in the Japanese economy has resulted in overall downward pressure on Alaska region Sablefish exvessel prices. Model simulations indicate that IFQ implementation in this fishery significantly increased exvessel revenues, beyond what they would have increased, as a consequence of longer seasons that resulted from an end of the race-for-fish. In addition, we find that IFQ implementation has helped buffer the fishery against revenue losses associated with reduced catch limits triggered by the decline of Sablefish biomass in the Alaska region
A televideo exercise and nutrition program for children with acute lymphoblastic leukemia in maintenance therapy: design and methods
Changes in nutrient intake and decreased exercise resulting from cancer therapies as well as their side effects may be contributing factors in the increased body weight and differences in physical fitness observed in survivors of childhood acute lymphoblastic leukemia (ALL). This article will describe the study protocol for an intervention program designed to improve the physical activity and nutrition behaviors of ALL survivors. Twenty-four children aged between 4 years and 12 years with ALL will be randomized to a 6-month technology-based exercise and nutrition program (TLC4ALLKids) or to enhanced usual care (eUC). The participants randomized to the TLC4ALLKids will participate in weekly, 1-hour coaching sessions on nutrition and physical activity and 1-hour physical activity classes delivered by group video conferencing. Participants will be provided with iPad tablets loaded with video conferencing software and the Healthy Lifestyle Tracking calendar to track daily nutrition and physical activity goals and weight. Both groups will be provided with Fitbitâą Zip to monitor physical activity. To assess feasibility, participant recruitment (achievement of proposed sample size), attendance (per weekly online sessions/assessment sessions), and adherence (number of families at 3 and 6 months) will be evaluated. Outcome measures to assess the intervention will include anthropometrics (weight, height, and waist circumference), physical activity (accelerometry), energy and macronutrient intake (food records), sleep habits (Children's Sleep Habits Questionnaire), and quality of life (Pediatric Quality of Life Inventory) will be obtained at baseline, 3 months, and 6 months. Semi-structured interviews will be used to gather information about ways to improve the program and overcome barriers to participation. If successful, the TLC4ALLKids intervention will provide a means to educate and improve the health behaviors of ALL survivors that can be delivered remotely and conveniently to participants
The Samurai Project: verifying the consistency of black-hole-binary waveforms for gravitational-wave detection
We quantify the consistency of numerical-relativity black-hole-binary
waveforms for use in gravitational-wave (GW) searches with current and planned
ground-based detectors. We compare previously published results for the
mode of the gravitational waves from an equal-mass
nonspinning binary, calculated by five numerical codes. We focus on the 1000M
(about six orbits, or 12 GW cycles) before the peak of the GW amplitude and the
subsequent ringdown. We find that the phase and amplitude agree within each
code's uncertainty estimates. The mismatch between the modes
is better than for binary masses above with respect to
the Enhanced LIGO detector noise curve, and for masses above
with respect to Advanced LIGO, Virgo and Advanced Virgo. Between the waveforms
with the best agreement, the mismatch is below . We find that
the waveforms would be indistinguishable in all ground-based detectors (and for
the masses we consider) if detected with a signal-to-noise ratio of less than
, or less than in the best cases.Comment: 17 pages, 9 figures. Version accepted by PR
Individual variability in cardiac biomarker release after 30 min of high-intensity rowing in elite and amateur athletes
This study had two objectives: (i) to examine individual variation in the pattern of cardiac troponin I (cTnI) and N-terminal pro-brain natriuretic peptide (NT-proBNP) release in response to high-intensity rowing exercise, and (ii) to establish whether individual heterogeneity in biomarker appearance was influenced by athletic status (elite vs. amateur). We examined cTnI and NT-proBNP in 18 elite and 14 amateur rowers before and 5 min, 1, 3, 6, 12, and 24 h after a 30-min maximal rowing test. Compared with pre-exercise levels, peak postexercise cTnI (pre: 0.014 ± 0.030 ÎŒg·Lâ1; peak post: 0.058 ± 0.091 ÎŒg·Lâ1; p = 0.000) and NT-proBNP (pre: 15 ± 11 ng·Lâ1; peak post: 31 ± 19 ng·Lâ1; p = 0.000) were elevated. Substantial individual heterogeneity in peak and time-course data was noted for cTnI. Peak cTnI exceeded the upper reference limit (URL) in 9 elite and 3 amateur rowers. No rower exceeded the URL for NT-proBNP. Elite rowers had higher baseline (0.019 ± 0.038 vs. 0.008 ± 0.015 ÎŒg·Lâ1; p = 0.003) and peak postexercise cTnI (0.080 ± 0.115 vs. 0.030 ± 0.029 ÎŒg·Lâ1; p = 0.022) than amateur rowers, but the change with exercise was similar between groups. There were no significant differences in baseline and peak postexercise NT-proBNP between groups. In summary, marked individuality in the cTnI response to a short but high-intensity rowing bout was observed. Athletic status did not seem to affect the change in cardiac biomarkers in response to high-intensity exercise
Testing gravitational-wave searches with numerical relativity waveforms: Results from the first Numerical INJection Analysis (NINJA) project
The Numerical INJection Analysis (NINJA) project is a collaborative effort
between members of the numerical relativity and gravitational-wave data
analysis communities. The purpose of NINJA is to study the sensitivity of
existing gravitational-wave search algorithms using numerically generated
waveforms and to foster closer collaboration between the numerical relativity
and data analysis communities. We describe the results of the first NINJA
analysis which focused on gravitational waveforms from binary black hole
coalescence. Ten numerical relativity groups contributed numerical data which
were used to generate a set of gravitational-wave signals. These signals were
injected into a simulated data set, designed to mimic the response of the
Initial LIGO and Virgo gravitational-wave detectors. Nine groups analysed this
data using search and parameter-estimation pipelines. Matched filter
algorithms, un-modelled-burst searches and Bayesian parameter-estimation and
model-selection algorithms were applied to the data. We report the efficiency
of these search methods in detecting the numerical waveforms and measuring
their parameters. We describe preliminary comparisons between the different
search methods and suggest improvements for future NINJA analyses.Comment: 56 pages, 25 figures; various clarifications; accepted to CQ
Shear velocity model for the Kyrgyz Tien Shan from joint inversion of receiver function and surface wave data
The Tien Shan is the largest active intracontinental orogenic belt on Earth. To better
understand the processes causing mountains to form at great distances from a plate
boundary, we analyse passive source seismic data collected on 40 broad band stations
of the MANAS project (2005-2007) and 12 stations of the permanent KRNET seismic
network to determine variations in crustal thickness and shear wavespeed across the
range. We jointly invert P- and S-wave receiver functions with surface wave observations
from both earthquakes and ambient noise to reduce the ambiguity inherent in the images
obtained from the techniques applied individually. Inclusion of ambient noise data improves constraints on the upper crust by allowing dispersion measurements to be made
at shorter periods. Joint inversion can also reduce the ambiguity in interpretation by
revealing the extent to which various features in the receiver functions are ampliïŹed
or eliminated by interference from multiples. The resulting wavespeed model shows a
variation in crustal thickness across the range. We ïŹnd that crustal velocities extend
to ⌠75 km beneath the Kokshaal Range, which we attribute to underthrusting of the
Tarim Basin beneath the southern Tien Shan. This result supports the plate model of
intracontinental convergence. Crustal thickness elsewhere beneath the range is about 50 km, including beneath the Naryn Valley in the central Tien Shan where previous studies
reported a shallow Moho. This diïŹerence apparently is the result of wavespeed variations
in the upper crust that were not previously taken into account. Finally, a high velocity
lid appears in the upper mantle of the Central and Northern part of the Tien Shan,
which we interpret as a remnant of material that may have delaminated elsewhere under
the range.km, including beneath the Naryn Valley in the central Tien Shan where previous studies
reported a shallow Moho. This diïŹerence apparently is the result of wavespeed variations
in the upper crust that were not previously taken into account. Finally, a high velocity
lid appears in the upper mantle of the Central and Northern part of the Tien Shan,
which we interpret as a remnant of material that may have delaminated elsewhere under
the range.This is the final published version. It's also available from Oxford Journals at http://gji.oxfordjournals.org/content/199/1/480.full
Feasibility of sex-sorting sperm from the white and the black rhinoceros (Ceratotherium simum, Diceros bicornis)
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