13,153 research outputs found
Seafood Import Demand in the Caribbean Region
Cointegration analysis and an Error Correction Model are used to estimate aggregate seafood import demand functions for selected Caribbean countries. The results show that seafood import demand is price elastic. Exchange rate has a negative effect on seafood import quantity. Income and tourist arrivals have positive impacts on seafood imports. Seafood import negatively affects domestic fishery production. Tariff and production support policies reduce seafood imports, and enhance domestic production. Both policies increase producer surplus, but a tariff reduces consumer surplus, and a production expansion policy increases consumer surplus. A production expansion subsidy is a more appropriate policy instrument than a tariff for small open economies, like the Caribbean States, to increase domestic production and generate net economic surplus.Seafood, import demand, cointegration, economic surplus, Agricultural and Food Policy, International Relations/Trade, Q17, Q22, C32,
The Centaurus A Northern Middle Lobe as a Buoyant Bubble
We model the northern middle radio lobe of Centaurus A (NGC 5128) as a
buoyant bubble of plasma deposited by an intermittently active jet. The extent
of the rise of the bubble and its morphology imply that the ratio of its
density to that of the surrounding ISM is less than 10^{-2}, consistent with
our knowledge of extragalactic jets and minimal entrainment into the precursor
radio lobe. Using the morphology of the lobe to date the beginning of its rise
through the atmosphere of Centaurus A, we conclude that the bubble has been
rising for approximately 140Myr. This time scale is consistent with that
proposed by Quillen et al. (1993) for the settling of post-merger gas into the
presently observed large scale disk in NGC 5128, suggesting a strong connection
between the delayed re-establishment of radio emission and the merger of NGC
5128 with a small gas-rich galaxy. This suggests a connection, for radio
galaxies in general, between mergers and the delayed onset of radio emission.
In our model, the elongated X-ray emission region discovered by Feigelson et
al. (1981), part of which coincides with the northern middle lobe, is thermal
gas that originates from the ISM below the bubble and that has been uplifted
and compressed. The "large-scale jet" appearing in the radio images of Morganti
et al. (1999) may be the result of the same pressure gradients that cause the
uplift of the thermal gas, acting on much lighter plasma, or may represent a
jet that did not turn off completely when the northern middle lobe started to
buoyantly rise. We propose that the adjacent emission line knots (the "outer
filaments") and star-forming regions result from the disturbance, in particular
the thermal trunk, caused by the bubble moving through the extended atmosphere
of NGC 5128.Comment: 38 pages, 13 figures, submitted to ApJ; a version with higher
  resolution figures is available at
  http://www.mso.anu.edu.au/~saxton/papers/cena.pd
Resolution of the strong CP problem
It is shown that the quark mass aligns QCD  vacuum in such a way that
the strong CP is conserved, resolving the strong CP problem.Comment: 9 pages;v2 slightly rewritten and expanded;v3 a few points
  clarified;v4 minor changes, journal versio
Interactions of Jets with Inhomogeneous Cloudy Media
We present two-dimensional slab-jet simulations of jets in inhomogeneous
media consisting of a tenuous hot medium populated with a small filling factor
by warm, dense clouds. The simulations are relevant to the structure and
dynamics of sources such as Gigahertz Peak Spectrum and Compact Steep Spectrum
radio galaxies, High Redshift Radio Galaxies and radio galaxies in cooling
flows. The jets are disrupted to a degree depending upon the filling factor of
the clouds. With a small filling factor, the jet retains some forward momentum
but also forms a halo or bubble around the source. At larger filling factors
channels are formed in the cloud distribution through which the jet plasma
flows and a hierarchical structure consisting of nested lobes and an outer
enclosing bubble results. We suggest that the CSS quasar 3C48 is an example of
a low filling factor jet - interstellar medium interaction whilst M87 may be an
example of the higher filling factor type of interaction. Jet disruption occurs
primarily as a result of Kelvin-Helmholtz instabilities driven by turbulence in
the radio cocoon not through direct jet-cloud interactions, although there are
some examples of these. In all radio galaxies whose morphology may be the
result of jet interactions with an inhomogeneous interstellar medium we expect
that the dense clouds will be optically observable as a result of radiative
shocks driven by the pressure of the radio cocoon. We also expect that the
radio galaxies will possess faint haloes of radio emitting material well beyond
the observable jet structure.Comment: 21 pages, 16 figures, submitted to MNRAS. A version with full
  resolution figures is available at:
  http://www.mssl.ucl.ac.uk/~cjs2/pdf/cloudy_hue.pd
A REGIONAL COMPARISON OF U.S. COTTON BASIS PATTERNS
The basis, defined as the cash price minus the futures price, is important when making marketing decisions. The cotton basis is calculated using the July futures price for six major cotton marketing regions in the U.S. for August 1993 to November 1997. Graphs of the average basis for the four complete crop years show that the basis generally followed the expected seasonal pattern. The basis tended to be weakest at harvest and to strengthen later in the crop year. However, a visual inspection showed regional differences in the seasonal pattern. Regional differences in the yearly variability in the basis were also observed. Thus, the usefulness of the average historical basis in predicting the future basis appears to differ depending on the region.Demand and Price Analysis,
Planned, motivated and habitual hygiene behaviour: an eleven country review.
Handwashing with soap (HWWS) may be one of the most cost-effective means of preventing infection in developing countries. However, HWWS is rare in these settings. We reviewed the results of formative research studies from 11 countries so as to understand the planned, motivated and habitual factors involved in HWWS. On average, only 17% of child caretakers HWWS after the toilet. Handwash 'habits' were generally not inculcated at an early age. Key 'motivations' for handwashing were disgust, nurture, comfort and affiliation. Fear of disease generally did not motivate handwashing, except transiently in the case of epidemics such as cholera. 'Plans' involving handwashing included to improve family health and to teach children good manners. Environmental barriers were few as soap was available in almost every household, as was water. Because much handwashing is habitual, self-report of the factors determining it is unreliable. Candidate strategies for promoting HWWS include creating social norms, highlighting disgust of dirty hands and teaching children HWWS as good manners. Dividing the factors that determine health-related behaviour into planned, motivated and habitual categories provides a simple, but comprehensive conceptual model. The habitual aspects of many health-relevant behaviours require further study
Don't look, don't touch, the science behind revulsion
Every flu season, sneezing, coughing, and graphic throat-clearing become the day-to-day background noise in every workplace. And coworkers tend to move as far—and as quickly—away from the source of these bodily eruptions as possible. Instinctively, humans recoil from objects that they view as dirty and even struggle to overcome feelings of discomfort once the offending item has been cleaned. These reactions are universal, and although there are cultural and individual variations, by and large we are all disgusted by the same things.
            In Don’t Look, Don’t Touch, Don’t Eat, Valerie Curtis builds a strong case for disgust as a “shadow emotion”—less familiar than love or sadness, it nevertheless affects our day-to-day lives. In disgust, biological and sociocultural factors meet in dynamic ways to shape human and animal behavior. Curtis traces the evolutionary role of disgust in disease prevention and hygiene, but also shows that it is much more than a biological mechanism. Human social norms, from good manners to moral behavior, are deeply rooted in our sense of disgust. The disgust reaction informs both our political opinions and our darkest tendencies, such as misogyny and racism. Through a deeper understanding of disgust, Curtis argues, we can take this ubiquitous human emotion and direct it towards useful ends, from combating prejudice to reducing disease in the poorest parts of the world by raising standards of hygiene.
            Don’t Look, Don’t Touch, Don’t Eat reveals disgust to be a vital part of what it means to be human and explores how this deep-seated response can be harnessed to improve the world
Laminin receptors in the retina: sequence analysis of the chick integrin alpha 6 subunit. Evidence for transcriptional and posttranslational regulation.
The integrin alpha 6 beta 1 is a prominent laminin receptor used by many cell types. In the present work, we isolate clones and determine the primary sequence of the chick integrin alpha 6 subunit. We show that alpha 6 beta 1 is a prominent integrin expressed by cells in the developing chick retina. Between embryonic days 6 and 12, both retinal ganglion cells and other retinal neurons lose selected integrin functions, including the ability to attach and extend neurites on laminin. In retinal ganglion cells, we show that this is correlated with a dramatic decrease in alpha 6 mRNA and protein, suggesting that changes in gene expression account for the developmental regulation of the interactions of these neurons with laminin. In other retinal neurons the expression of alpha 6 mRNA and protein remains high while function is lost, suggesting that the function of the alpha 6 beta 1 heterodimer in these cells is regulated by posttranslational mechanisms
Comparison of structured observation and pictorial 24 h recall of household activities to measure the prevalence of handwashing with soap in the community.
This study compared structured observation with a 24 h pictorial recall of household activities ('sticker diary') to measure the prevalence of handwashing with soap (HWWS) in the community. The study was done within a cluster-randomised trial evaluating a handwashing promotion programme in Bihar, India. HWWS at key occasions in mothers and school children was measured by structured observation in 299 households from 32 villages. Sticker diaries recalling common activities, including personal hygiene, were used to measure HWWS in 299 households from a further 20 villages. Sticker diary HWWS prevalence estimates were about 13% points higher than structured observation estimates, but the differences varied by the type of handwashing occasion. This study confirms structured observation as the method of choice for the study of handwashing behaviours. The sticker diary method may be useful in large-scale surveys. Sticker diaries may overestimate HWWS at important occasions, but probably less so than conventional questionnaire tools
- …
