A review of the population structure of yellowfin tuna, Thunnus albacares, in the Eastern Pacific Ocean

ENGLISH: Since its inception in 1950 by agreement between the Republic of Costa Rica and the United States of America, the Inter-American Tropical Tuna Commission has been engaged in studies of the biology, ecology and population dynamics of yellowfin tuna in the eastern Pacific Ocean. Prime consideration has been given to the evaluation of the effects of fishing pressure on the yellowfin tuna in this area in order to estimate the maximum sustainable yield. A portion of the eastern Pacific has been defined by the Inter-American Tropical Tuna Commission (1963) as a regulatory area for yellowfin tuna (Figure 1). SPANISH: Desde su incepción en 1950, por un acuerdo entre la República de Costa Rica y los Estados Unidos de América, la Comisión Interamericana del Atún Tropical ha estado ocupada en los estudios de la biología, ecología y dinámica de las poblaciones del atún aleta amarilla en el Océano Pacífico Oriental. Se consideró primariamente la evaluación de los efectos de la presión de la pesquería sobre el atún aleta amarilla en esta área, para poder estimar el rendimiento máximo sostenible. Una parte del Pacífico Oriental ha sido definida por la Comisión Interamericana del Atún Tropical (1963), como área de reglamentación del atún aleta amarilla (Figura 1). (PDF contains 60 pages.

Long-memory processes in ozone and temperature variations at the region 60° S?60° N

International audienceGlobal column ozone and tropospheric temperature observations made by ground-based (1964?2004) and satellite-borne (1978?2004) instrumentation are analyzed. Ozone and temperature fluctuations in small time-intervals are found to be positively correlated to those in larger time-intervals in a power-law fashion. For temperature, the exponent of this dependence is larger in the mid-latitudes than in the tropics at long time scales, while for ozone, the exponent is larger in tropics than in the mid-latitudes. In general, greater persistence could be a result of either stronger positive feedbacks or larger inertia. Therefore, the increased slope of the power distribution of temperature in mid-latitudes at long time scales compared to the slope in the tropics could be connected to the poleward increase in climate sensitivity predicted by the global climate models. The detrended fluctuation analysis of model and observed time series provides a helpful tool for visualizing errors in the treatment of long-range correlations, whose correct modeling would greatly enhance confidence in long-term climate and atmospheric chemistry modeling

Squaring the Circle: The Cultural Relativity of 'Good' Shape

The Gestalt theorists of the early twentieth century proposed a psychological primacy for circles, squares and triangles over other shapes. They described them as 'good' shapes and the Gestalt premise has been widely accepted. Rosch (1973), for example, suggested that shape categories formed around these 'natural' prototypes irrespective of the paucity of shape terms in a language. Rosch found that speakers of a language lacking terms for any geometric shape nevertheless learnt paired-associates to these 'good' shapes more easily than to asymmetric variants. We question these empirical data in the light of the accumulation of recent evidence in other perceptual domains that language affects categorization. A cross-cultural investigation sought to replicate Rosch's findings with the Himba of Northern Namibia who also have no terms in their language for the supposedly basic shapes of circle, square and triangle. A replication of Rosch (1973) found no advantage for these 'good' shapes in the organization of categories. It was concluded that there is no necessary salience for circles, squares and triangles. Indeed, we argue for the opposite because these shapes are rare in nature. The general absence of straight lines and symmetry in the perceptual environment should rather make circles, squares and triangles unusual and, therefore, less likely to be used as prototypes in categorization tasks. We place shape as one of the types of perceptual input (in philosophical terms, 'vague') that is readily susceptible to effects of language variation

Maintenance of polar stratospheric clouds in a moist stratosphere

Previous work has shown that polar stratospheric clouds (PSCs) could have acted to substantially warm high latitude regions during past warm climates such as the Eocene (55 Ma). Using a simple model of stratospheric water vapor transport and polar stratospheric cloud (PSC) formation, we investigate the dependence of PSC optical depth on tropopause temperature, cloud microphysical parameters, stratospheric overturning, and tropospheric methane. We show that PSC radiative effects can help slow removal of water from the stratosphere via self-heating. However, we also show that the ability of PSCs to have a substantial impact on climate depends strongly on the PSC particle number density and the strength of the overturning circulation. Thus even a large source of stratospheric water vapor (e.g. from methane oxidation) will not result in substantial PSC radiative effects unless PSC ice crystal number density is high compared to most current observations, and stratospheric overturning (which modulates polar stratospheric temperatures) is low. These results are supported by analysis of a series of runs of the NCAR WACCM model with methane concentrations varying up to one thousand times present levels

Long-memory processes in global ozone and temperature variations

International audienceGlobal column ozone and tropospheric temperature observations made by ground-based (1964?2004) and satellite-borne (1978?2004) instrumentation are analyzed. Ozone and temperature fluctuations in small time-intervals are found to be positively correlated to those in larger time-intervals in a power-law fashion. For temperature, the exponent of this dependence is larger in the mid-latitudes than in the tropics at long time scales, while for ozone, the exponent is larger in tropics than in the mid-latitudes. The ability of the models to reproduce this scaling could be a good test for improved predictions of future variations in ozone layer and global warming

Bayes and health care research.

Bayes’ rule shows how one might rationally change one’s beliefs in the light of evidence. It is the foundation of a statistical method called Bayesianism. In health care research, Bayesianism has its advocates but the dominant statistical method is frequentism. There are at least two important philosophical differences between these methods. First, Bayesianism takes a subjectivist view of probability (i.e. that probability scores are statements of subjective belief, not objective fact) whilst frequentism takes an objectivist view. Second, Bayesianism is explicitly inductive (i.e. it shows how we may induce views about the world based on partial data from it) whereas frequentism is at least compatible with non-inductive views of scientific method, particularly the critical realism of Popper. Popper and others detail significant problems with induction. Frequentism’s apparent ability to avoid these, plus its ability to give a seemingly more scientific and objective take on probability, lies behind its philosophical appeal to health care researchers. However, there are also significant problems with frequentism, particularly its inability to assign probability scores to single events. Popper thus proposed an alternative objectivist view of probability, called propensity theory, which he allies to a theory of corroboration; but this too has significant problems, in particular, it may not successfully avoid induction. If this is so then Bayesianism might be philosophically the strongest of the statistical approaches. The article sets out a number of its philosophical and methodological attractions. Finally, it outlines a way in which critical realism and Bayesianism might work together. </p

Gestational age at delivery and special educational need: retrospective cohort study of 407,503 schoolchildren

&lt;STRONG&gt;Background&lt;/STRONG&gt; Previous studies have demonstrated an association between preterm delivery and increased risk of special educational need (SEN). The aim of our study was to examine the risk of SEN across the full range of gestation. &lt;STRONG&gt;Methods and Findings&lt;/STRONG&gt; We conducted a population-based, retrospective study by linking school census data on the 407,503 eligible school-aged children resident in 19 Scottish Local Authority areas (total population 3.8 million) to their routine birth data. SEN was recorded in 17,784 (4.9%) children; 1,565 (8.4%) of those born preterm and 16,219 (4.7%) of those born at term. The risk of SEN increased across the whole range of gestation from 40 to 24 wk: 37–39 wk adjusted odds ratio (OR) 1.16, 95% confidence interval (CI) 1.12–1.20; 33–36 wk adjusted OR 1.53, 95% CI 1.43–1.63; 28–32 wk adjusted OR 2.66, 95% CI 2.38–2.97; 24–27 wk adjusted OR 6.92, 95% CI 5.58–8.58. There was no interaction between elective versus spontaneous delivery. Overall, gestation at delivery accounted for 10% of the adjusted population attributable fraction of SEN. Because of their high frequency, early term deliveries (37–39 wk) accounted for 5.5% of cases of SEN compared with preterm deliveries (&lt;37 wk), which accounted for only 3.6% of cases. &lt;STRONG&gt;Conclusions&lt;/STRONG&gt; Gestation at delivery had a strong, dose-dependent relationship with SEN that was apparent across the whole range of gestation. Because early term delivery is more common than preterm delivery, the former accounts for a higher percentage of SEN cases. Our findings have important implications for clinical practice in relation to the timing of elective delivery

noxin, a novel stress-induced gene involved in cell cycle and apoptosis

We describe a novel stress-induced gene, noxin, and a knockout mouse line with an inactivated noxin gene. The noxin gene does not have sequelogs in the genome and encodes a highly serine-rich protein with predicted phosphorylation sites for ATM, Akt, and DNA-dependent protein kinase kinases; nuclear localization signals; and a Zn finger domain. noxin mRNA and protein levels are under tight control by the cell cycle. noxin, identified as a nitric oxide-inducible gene, is strongly induced by a wide range of stress signals: gamma- and UV irradiation, hydrogen peroxide, adriamycin, and cytokines. This induction is dependent on p53. Noxin accumulates in the nucleus in response to stress and, when ectopically expressed, Noxin arrests the cell cycle at G1; although it also induces p53, the cell cycle arrest function of Noxin is independent of p53 activity. noxin knockout mice are viable and fertile; however, they have an enlarged heart, several altered hematopoietic parameters, and a decreased number of spermatids. Importantly, loss or downregulation of Noxin leads to increased cell death. Our results suggest that Noxin may be a component of the cell defense system: it is activated by various stress stimuli, helps cells to withdraw from cycling, and opposes apoptosis

Gender, migration and the ambiguous enterprise of professionalizing domestic service: the case of vocational training for the unemployed in France

Drawing on ethnographic data concerning migrant male domestic workers, this article examines the gendered dimensions of the process of racialization in Italy and France. First, it shows that specific racialized constructions of masculinity are mobilized by the employers as well as by training and recruitment agencies. These constructions of masculinity are related to different forms of organization of the sector in each country and to different ideologies about the integration of migrants. Second, the data presented reveal the strategies used by migrant male domestic workers to reaffirm their masculinity in a traditionally feminized sector. In doing so, this article intends to explore the connections between international migration and the gendering of occupations, with regard to the construction and management of masculinities in domestic service. Finally, by examining men’s experiences, this article aims to contribute to a more complex definition of the international division of care work