2,069 research outputs found
Modelling Irelandâs Exchange Rates - From EMS to EMU
This paper attempts to model the nominal and real exchange rate for Ireland, relative to Germany and the UK from 1975 to 2003. It offers an overview of the theory of purchasing power parity (Ppp), focusing particularly on likely sources of nonlinearity. Potential difficulties in placing the analysis in the standard I(1)/I(0) framework are highlighted and comparisons with previous Irish studies are made. Tests for fractional integration and nonlinearity, including random field regressions, are discussed and applied. The results obtained highlight the likely inadequacies of the standard cointegration and Star approaches to modelling, and point instead to multiple structural changes models. Using this approach, both bilateral nominal exchange rates are effectively modelled, and in the case of Ireland and Germany, Ppp is found to be valid not only in the long run, but also in the medium term.Purchasing power parity; fractional Dickey-Fuller tests; smooth transition autoregression; random field regression; multiple structural changes models
Tracking Pacific bluefin tuna (Thunnus thynnus orientalis) in the northeastern Pacific with an automated algorithm that estimates latitude by matching sea-surface-temperature data from satellites with temperature data from tags on fish
Data recovered from 11 popup satellite archival tags and 3
surgically implanted archival tags were used to analyze the movement patterns of juvenile northern bluefin tuna (Thunnus thynnus orientalis) in the eastern Pacific. The light sensors on archival and pop-up satellite transmitting
archival tags (PSATs) provide data on the time of sunrise
and sunset, allowing the calculation of an approximate geographic position of the animal. Light-based estimates
of longitude are relatively robust but latitude estimates are prone to large degrees of error, particularly near the times of the equinoxes and when the tag is at low latitudes. Estimating latitude remains a problem for
researchers using light-based geolocation algorithms and it has been suggested that sea surface temperature data from satellites may be a useful tool for refining latitude estimates. Tag data from bluefin tuna were subjected to a newly developed algorithm, called âPSAT Tracker,â which automatically matches sea surface temperature data from the tags with sea surface temperatures recorded by satellites.
The results of this algorithm compared favorably to the estimates of latitude calculated with the lightbased
algorithms and allowed for estimation of fish positions during times of the year when the lightbased algorithms failed. Three near one-year tracks produced by PSAT tracker showed that the fish range from the CaliforniaâOregon border
to southern Baja California, Mexico, and that the majority of time is spent off the coast of central Baja Mexico. A seasonal movement pattern was evident; the fish spend winter and spring off central Baja California, and summer through fall is spent moving northward to Oregon and returning to Baja California
Nonlinearity as an Explanation of the Forward Exchange Rate Anomaly
This paper shows that nonlinearity can provide an explanation for the forward exchange rate anomaly (Fama, 1984). Using sterling-Canadian dollar data, and modelling nonlinearity of unspecified form by means of a random field, we find strong evidence of time-wise nonlinearity and, significantly, obtain parameter estimates that conform with theory to a high degree of precision: the anomaly disappears.Forward exchange rate anomaly; nonlinearity; random field regression
Spectral Properties From Lyman-alpha to H-alpha For An Essentially Complete Sample of Quasars I: Data
We have obtained quasi-simultaneous ultraviolet-optical spectra for 22 out of
23 quasars in the complete PG-X-ray sample with redshift, z<0.4, and M_B<-23.
The spectra cover rest-frame wavelengths from at least Lyman-alpha to H-alpha.
Here we provide a detailed description of the data, including careful
spectrophotometry and redshift determination. We also present direct
measurements of the continua, strong emission lines and features, including
Lyman-alpha, SiIV+OIV], CIV, CIII], SiIII], MgII, H-beta, [OIII],
He5876+NaI5890,5896, H-alpha, and blended iron emission in the UV and optical.
The widths, asymmetries and velocity shifts of profiles of strong emission
lines show that CIV and Lyman-alpha are very different from H-beta and H-alpha.
This suggests that the motion of the broad line region is related to the
ionization structure, but the data appears not agree with the radially
stratified ionization structure supported by reverberation mapping studies, and
therefore suggest that outflows contribute additional velocity components to
the broad emission line profiles.Comment: 42 pages, 10 figures, 13 tables. Accepted by AJ. Supplemental figures
not included. Full version available at
http://physics.uwyo.edu/~shang/pgxpaper/ShangPaper.pd
TECHNICAL FISHERY INTERACTIONS IN SOUTHERN BRAZIL
Technical interactions arise through the incidental catch of non-target species (by-catch) in targeted fisheries and by the co-existence of fleets exploiting the same resource. This study revises the fishery, gears and species captured in southern Brazil and also identifies the technical interactions between the fleets and the species involved (through mixed catch and by-catch), especially of the bluefish, Pomatomus saltatrix, and the striped weakfish, Cynoscion guatucupa. Data was taken from published material about the southern Brazilian continental shelf fishery, catch records from coastal landing sites, interviews with skippers and managers and data collected by the IBAMA (Instituto Brasileiro do Meio Ambiente e dos Recursos Naturais RenovĂĄveis). The demersal teleosts are the most exploited resources, notably the Sciaenids Micropogonias furnieri, C. guatucupa, Umbrina canosai and Macrodon ancylodon (55% in weight). The higher proportion of by-catch of the targeted P. saltatrix by gill netting is due to Brevoortia pectinata and Parona signata. The targeted C. guatucupa by gill netting is more species-diverse. M. furnieri gill netting is very species-selective as only 4% on average of the total catch is regarded as incidental. Trawlers may catch up to 20 species and there is no specific target species. Purse seine is a species-specific gear as, for most of the targeted species, the by-catch is less than 1% by weight. The size range of the exploited P. saltatrix and C. guatucupa differs amongst gears.  RESUMO InteraçÔes tĂ©cnicas na atividade pesqueira do sul do Brasil InteraçÔes tĂ©cnicas estĂŁo relacionadas com a captura incidental de espĂ©cies nĂŁo alvo (fauna acompanhante) em pescarias direcionadas e, pela co-existĂȘncia de frotas explorando o mesmo recurso. Este estudo revisa a pesca, artes de pesca e espĂ©cies capturadas no sul do Brasil e tambĂ©m identifica as interaçÔes tĂ©cnicas entre frotas e espĂ©cies (atravĂ©s da captura mista ou fauna acompanhante), especialmente para a anchova, Pomatomus saltatrix, e pescada olhuda, Cynoscion guatucupa. Os dados foram obtidos atravĂ©s de material publicado sobre a pesca da plataforma continetal do sul do Brasil, registros de pesca dos pontos de desembarque da pesca costeira, entrevista com mestres e armadores de barcos e dados coletados pelo IBAMA. TeleĂłsteos demersais sĂŁo os recursos mais explorados, principalmente os SciaenĂdeos Micropogonias furnieri, C. guatucupa, Umbrina canosai e Macrodon ancylodon (55% em peso). A maior proporção da fauna acompanhante da pescaria de rede de emalhe direcionada para o P. saltatrix sĂŁo das espĂ©cies Brevoortia pectinata e Parona signata. A pesca de emalhe direcionada para C. guatucupa Ă© mais diversificada. A pesca de emalhe direcionada para M. furnieri Ă© muito seletiva em termos de nĂșmero de espĂ©cies uma vez que apenas 4% em media da captura total Ă© incidental. Arrasteiros podem capturar atĂ© 20 diferentes espĂ©cies e nĂŁo hĂĄ uma espĂ©cie-alvo especĂfica. Rede de cerco Ă© uma arte especĂfica uma vez que, para a maioria das espĂ©cies-alvo, a fauna acompanhante Ă© menor que 1% em peso. A faixa de comprimento do P. saltatrix and C. guatucupa explorado difere entre as artes de pesca. Palavras chave: pesca, sul do Brasil, interaçÔes tĂ©cnicas.
High throughput genomic sequencing of bioaerosols in broiler chicken production facilities
Chronic inhalation exposure to agricultural dust promotes the development of chronic respiratory diseases among poultry workers. Poultry dust is composed of dander, chicken feed, litter bedding and microbes. However, the microbial composition and abundance has not been fully elucidated. Genomic DNA was extracted from settled dust and personal inhalable dust collected while performing litter sampling or mortality collection tasks. DNA libraries were sequenced using a paired-end sequencing-by-synthesis approach on an Illumina HiSeq 2500. Sequencing data showed that poultry dust is predominantly composed of bacteria (64â67%) with a small quantity of avian, human and feed DNA (\u3c 2% of total reads). Staphylococcus sp. AL1, Salinicoccus carnicancri and Lactobacillus crispatus were the most abundant bacterial species in personal exposure samples of inhalable dust. Settled dust had a moderate relative abundance of these species as well as Staphylococcus lentus and Lactobacillus salivarius. There was a statistical difference between the microbial composition of aerosolized and settled dust. Unlike settled dust composition, aerosolized dust composition had little variance between samples. These data provide an extensive analysis of the microbial composition and relative abundance in personal inhalable poultry dust and settled poultry dust
Risk of Resource Failure and Toolkit Variation in Small-Scale Farmers and Herders
Recent work suggests that global variation in toolkit structure among hunter-gatherers is driven by risk of resource failure such that as risk of resource failure increases, toolkits become more diverse and complex. Here we report a study in which we investigated whether the toolkits of small-scale farmers and herders are influenced by risk of resource failure in the same way. In the study, we applied simple linear and multiple regression analysis to data from 45 small-scale food-producing groups to test the risk hypothesis. Our results were not consistent with the hypothesis; none of the risk variables we examined had a significant impact on toolkit diversity or on toolkit complexity. It appears, therefore, that the drivers of toolkit structure differ between hunter-gatherers and small-scale food-producers
Is there a preference for PET or SPECT brain imaging in diagnosing dementia? The views of people with dementia, carers, and healthy controls
- âŠ