Effect of individual variability on estimation of population parameters from length-frequency data

We consider estimation of mortality rates and growth parameters from length-frequency data of a fish stock when there is individual variability in the von Bertalanffy growth parameter L-infinity and investigate the possible bias in the estimates when the individual variability is ignored. Three methods are examined: (i) the regression method based on the Beverton and Holt's (1956, Rapp. P.V. Reun. Cons. Int. Explor. Mer, 140: 67-83) equation; (ii) the moment method of Powell (1979, Rapp. PV. Reun. Int. Explor. Mer, 175: 167-169); and (iii) a generalization of Powell's method that estimates the individual variability to be incorporated into the estimation. It is found that the biases in the estimates from the existing methods are, in general, substantial, even when individual variability in growth is small and recruitment is uniform, and the generalized method performs better in terms of bias but is subject to a larger variation. There is a need to develop robust and flexible methods to deal with individual variability in the analysis of length-frequency data.

Variable Size Population NSGA-II: VPNSGA-II

Multi-objective optimization is an active field of research with broad applicability in aeronautics. This report details a variant of the original NSGA-II software aimed to improve the performances of such a widely used Genetic Algorithm in finding the optimal Pareto-front of a Multi-Objective optimization problem for the use of UAV and aircraft design and optimsaiton. Original NSGA-II works on a population of predetermined constant size and its computational cost to evaluate one generation is O(mn^2 ), being m the number of objective functions and n the population size. The basic idea encouraging this work is that of reduce the computational cost of the NSGA-II algorithm by making it work on a population of variable size, in order to obtain better convergence towards the Pareto-front in less time. In this work some test functions will be tested with both original NSGA-II and VPNSGA-II algorithms; each test will be timed in order to get a measure of the computational cost of each trial and the results will be compared.

Drink and drug driving in Australian young adult users and non-users of illicit stimulants

- Introduction There is limited understanding of how young adults’ driving behaviour varies according to long-term substance involvement. It is possible that regular users of amphetamine-type stimulants (i.e. ecstasy (MDMA) and methamphetamine) may have a greater predisposition to engage in drink/drug driving compared to non-users. We compare offence rates, and self-reported drink/drug driving rates, for stimulant users and non-users in Queensland, and examine contributing factors. - Methods The Natural History Study of Drug Use is a prospective longitudinal study using population screening to recruit a probabilistic sample of amphetamine-type stimulant users and non-users aged 19-23 years. At the 4 ½ year follow-up, consent was obtained to extract data from participants’ Queensland driver records (ATS users: n=217, non-users: n=135). Prediction models were developed of offence rates in stimulant users controlling for factors such as aggression and delinquency. - Results Stimulant users were more likely than non-users to have had a drink-driving offence (8.7% vs. 0.8%, p < 0.001). Further, about 26% of ATS users and 14% of non-users self-reported driving under the influence of alcohol during the last 12 months. Among stimulant users, drink-driving was independently associated with last month high-volume alcohol consumption (Incident Rate Ratio (IRR): 5.70, 95% CI: 2.24-14.52), depression (IRR: 1.28, 95% CI: 1.07-1.52), low income (IRR: 3.57, 95% CI: 1.12-11.38), and male gender (IRR: 5.40, 95% CI: 2.05-14.21). - Conclusions Amphetamine-type stimulant use is associated with increased long-term risk of drink-driving, due to a number of behavioural and social factors. Inter-sectoral approaches which target long-term behaviours may reduce offending rates.

The life history of Phalacrognathus Muelleri (Macleay) (Coleoptera: Lucanidae)

The life history of Phalacrognathus muelleri (Macleay) is described and aspects of its biology discussed. The species is restricted to the wet tropics of northern Queensland where it breeds in rotting wood in rainforest. Larvae have been extracted from the wood of 27 tree species in 13 families. All larvae found were in wood attacked by white rot fungi. The final instar larva is described. Larva, pupa, and parasites are figured.

Pheromone-mediated mass trapping and population diversion as strategies for suppressing Carpophilus spp. (Coleoptera: Nitidulidae) in Australian stone fruit orchards

1 Five experiments were conducted during 1995-99 in stone fruit orchards on the Central Coast and in inland New South Wales, Australia, on the use of synthetic aggregation pheromones and a coattractant to suppress populations of the ripening fruit pests Carpophilus spp. (Coleoptera: Nitidulidae). 2 Perimeter-based suppression traps baited with pheromone and coattractant placed at 3m intervals around small fruit blocks, caught large numbers of Carpophilus spp. Very small populations of Carpophilus spp. occurred within blocks, and fruit damage was minimal. 3 Carpophilus spp. populations in stone fruit blocks 15-370m from suppression traps were also small and non-damaging, indicating a large zone of pheromone attractivity. 4 Pheromone/coattractant-baited suppression traps appeared to divert Carpophilus spp. from nearby (130 m) ripening stone fruit. Ten metal drums containing decomposing fruit, baited with pheromone and treated with insecticide, attracted Carpophilus spp. and appeared to reduce populations and damage to ripening fruit at distances of 200-500 m. Populations and damage were significantly greater within 200m of the drums and may have been caused by ineffective poisoning or poor quality/overcrowding of fruit resources in the drums. 5 Suppression of Carpophilus spp. populations using synthetic aggregation pheromones and a coattractant appears to be a realistic management option in stone fruit orchards. Pheromone-mediated diversion of beetle populations from ripening fruit may be more practical than perimeter trapping, but more research is needed on the effective range of Carpophilus pheromones and the relative merits of trapping compared to attraction to insecticide-treated areas.

VegMachine - putting pastoralists in the picture

Australia’s rangelands are the extensive arid and semi-arid grazing lands that cover approximately 70% of the Australian continent. They are characterised by low and generally variable rainfall, low productivity and a sparse population. They support a number of industries including mining and tourism, but pastoralism is the primary land use. In some areas, the rangelands have a history of biological decline (Noble 1997), with erosion, loss of perennial native grasses and incursion of woody vegetation commonly reported in the scientific and lay literature. Despite our historic awareness of these trends, the establishment of systems to measure and monitor degradation, has presented numerous problems. The size and accessibility of Australia’s rangeland often mitigates development of extensive monitoring programs. So, too, securing on-going commitment from Government agencies to fund rangeland monitoring activities have led to either abandonment or a scaled-down approach in some instances (Graetz et al. 1986; Holm 1993). While a multiplicity of monitoring schemes have been developed for landholders at the property scale, and some have received promising initial uptake, relatively few have been maintained for more than a few years on any property without at least some agency support (Pickup et al. 1998). But, ironically, such property level monitoring tools can contribute significantly to local decisions about stock, infrastructure and sustainability. Research in recent decades has shown the value of satellites for monitoring change in rangelands (Wallace et al. 2004), especially in terms of tree and ground cover. While steadily improving, use of satellite data as a monitoring tool has been limited by the cost of the imagery, and the equipment and expertise needed to extract useful information from it. A project now under way in the northern rangelands of Australia is attempting to circumvent many of the problems through a monitoring system that allows property managers to use long-term satellite image sequences to quickly and inexpensively track changes in land cover on their properties

A design history of design: Complexity, criticality & cultural competence

Les histoires de l’art et du design ont délaissé, au cours desquatre dernières décennies, l’étude canonique des objets, des artistes/concepteurs et des styles et se sont tournées vers des recherches plus interdisciplinaires. Nous soutenons néanmoins que les historiens et historiennes du design doivent continuer de pousser leur utilisation d’approches puisant dans la culturelle matérielle et la criticalité afin de combler des lacunes dans l’histoire du design et de développer des méthodes et des approches pertinentes pour son étude. Puisant dans notre expérience d’enseignement auprès de la génération des « milléniaux », qui sont portés vers un « design militant », nous offrons des exemples pédagogiques qui ont aidé nos étudiants et étudiantes à assimiler des histoires du design responsables, engagées et réflexives et à comprendre la complexité et la criticalité du design.

Stock assessment of the Queensland-New South Wales tailor fishery (Pomatomus saltatrix)

Data on catch sizes, catch rates, length-frequency and age composition from the Australian east coast tailor fishery are analysed by three different population dynamic models: a surplus production model, an age-structured model, and a model in which the population is structured by both age and length. The population is found to be very heavily exploited, with its ability to reproduce dependent on the fishery’s incomplete selectivity of one-year-old fish. Estimates of recent harvest rates (proportion of fish available to the fishery that are actually caught in a single year) are over 80%. It is estimated that only 30–50% of one-year-old fish are available to the fishery. Results from the age-length-structured model indicate that both exploitable biomass (total mass of fish selected by the fishery) and egg production have fallen to about half the levels that prevailed in the 1970s, and about 40% of virgin levels. Two-year-old fish appear to have become smaller over the history of the fishery. This is assumed to be due to increased fishing pressure combined with non-selectivity of small one-year-old fish, whereby the one-year-old fish that survive fishing are small and grow into small two-year-old fish the following year. An alternative hypothesis is that the stock has undergone a genetic change towards smaller fish; the true explanation is unknown. The instantaneous natural mortality rate of tailor is hypothesised to be higher than previously thought, with values between 0.8 and 1.3 yr–1 consistent with the models. These values apply only to tailor up to about three years of age, and it is possible that a lower value applies to fish older than three. The analysis finds no evidence that fishing pressure has yet affected recruitment. If a recruitment downturn were to occur, however, under current management and fishing pressure there is a strong chance that the fishery would need a complete closure for several years to recover, and even then recovery would be uncertain. Therefore it is highly desirable to better protect the spawning stock. The major recommendations are • An increase in the minimum size limit from 30cm to 40cm in order to allow most one-year-old fish to spawn, and • An experiment on discard mortality to gauge the proportion of fish between 30cm and 40cm that are likely to survive being caught and released by recreational line fishers (the dominant component of the fishery, currently harvesting roughly 1000t p.a. versus about 200t p.a. from the commercial fishery).

Family type and depression in pregnancy: Factors mediating risk in a community sample

The rate of severe depression among women in single-parent and biological families and in a variety of stepfamilies was examined in a large community sample of 13,088 pregnant women in the United Kingdom. Compared with women in biological families and published population rates, women in single-parent families and step-families reported significantly elevated rates of depression. Family-type differences in several risk factors were examined, including cohabiting (vs. married) status, relationship history, and socioeconomic and psychosocial risks, such as crowding, social support, and stressful life events. Family-type differences in depression were mediated partly by differences in social support, stressful life events, and crowding, but a main effect of family type in predicting depression remained after statistically controlling for these risks.

Herätys kylässä ja tuvissa : Rääkkylän Oravisalon kylä ja renqvistiläinen herätys 1820-luvulla

A Revival in a Village and its Households. The Village of Oravisalo in Rääkkylä Parish and the Renqvistist Revivalism in the 1820s. My purpose is to apply the science of religion and the study of past communities to the study of religious revivalism. Revivalism will be considered a religious phenomenon as well as a cultural and social phenomenon. What makes this study unique is the possibility to reconstruct a list of participating revivalists based on entries in the communion book of the time. The conflict between the revivalists and the chaplain of Rääkkylä also generated other documentary material. The community in Oravisalo was relatively stratified. People lived in complex and varying forms of households. They also had plentiful contacts both with unrelated inhabitants of Oravisalo and with the neighbouring villages. Through these contacts the inhabitants of Oravisalo were introduced to revivalism. In Oravisalo, the revival for the most part fell into a certain social stratum and did not severely damage existing relationships within families or among acquaintances. The revivalists formed a new community within the village but the community was neither very tightly-knit nor was it closed. The revival was an individual phenomenon affected by general factors. First, there were factors that brought about a quest for an applicable system of meanings. These factors included at least three important issues: the Great Partition of land, the crisis of slash-and-burn cultivation, and a population growth that increased the proportion of the landless in the village. As a result, many of the revivalists had low status and poor expectations for the future. Second, there were factors that appealed to the people in the message and character of the preacher, Henrik Renqvist. Third, the proximity of the village to Liperi, where the revival got its start, was crucial to revivalism s spread to Oravisalo. Culturally, the revival meant a change in the system of symbols or meanings, so it was not solely a matter of intensified religious fervour. For instance, Communion, prayer, reading, and perhaps baptism symbolised different things to the revivalists than to other villagers. However, the revivalists do not seem to have started any moral revolution in their village. The religious aspect defined the limits of the protest and the resistance towards authorities. The revivalists wanted only to have the right to follow their conscience. The freedom granted the female members was limited to the religious sphere. No social or economic claims were made. The revival altered the situation of its members only on a symbolic level, yet it also offered them status within their own group.

Ylirajaisia suhteita : Helsingin olympialaiset, Armi Kuusela ja ylikansallinen historia

In 1952 Helsinki hosted the Summer Olympic Games and Armi Kuusela, the current “Maiden of Finland”, was at the same time crowned Miss Universe. In popular history writing, these events have been designated as a crucial turning point – the end of an era marked by war and deprivation and the beginning of a modern, Western nation. Symptomatically, both events were marked by Finnish women’s sexual relationships with foreign men. The Olympics were shadowed by a concern over Finnish women’s “undue friendliness” with the Olympic guests, and Armi Kuusela's world tour was cut short by her surprise marriage in Tokyo and subsequent emigration to the Philippines. This study is an inquiry into the Helsinki Olympics and the public persona of Armi Kuusela from the point of view of transnational heterosexuality and the constitution of Finnish national identity. Methodologically the two main components of the study are intersectionality, defined here as a focus on the mutual histories and effects of discourses of gender, sexuality, race and nation; and transnational history as a way of exploring the ways that both nations and sexual subjects are embedded in global relations of power. The analysis proceeds by way of contextual and intertextual readings of various sources. Part one, centering on the Olympics, involves a campaign mounted by certain women’s organizations before the Games in order to educate young women about the potential dangers of the forthcoming international event as well as magazine and newspaper articles published during and after the Games concerning the encounter between young Finnish women and foreign, especially “Southern,” men. It places the debates during the Olympics within the framework of wartime understandings of women’s sexuality; the history of the concept of decency (siveellisyys); post-war population policy; the intersectional histories of conceptions pertaining to race and sexuality; and finally, the post-war concerns over women’s migration from rural areas to the capital city and their potential emigration abroad. Part two deals with the persona of Armi Kuusela and the public reception of her world tour and marriage, based on material from both Finland and the Philippines (newspapers, magazines, advertisements, books and films). It examines the persona of Armi Kuusela as a figure of national import in terms of the East/West divide; the racialized images of different geographic climates and Oriental “Others;” the meaning of whiteness in the Philippines; the significance of class and colonial history for the domestication of sexual and racial transgressions implied by an unconventional transnational marriage; as well as the cultural logics of transnational desire and its possible meanings for women in 1950s Finland. The study develops two arguments. First, it suggests that instead of being purely oppositional to national discourses, transnational desire may also be viewed as a product of these very discourses. Second, it claims that the national significance of both the Olympics and the persona of Armi Kuusela was due to the new points of comparison they both offered for national identity construction. In comparison with the sexualized Southern men at the Olympics and the racialized Orient in the representations of Armi Kuusela’s travels and marriage, Finland emerged as part of the civilized North, placed firmly within the perimeters of Western Europe. As such, both events mark a “whitening” of the Finnish people as well as a distancing from their previous designations in racial hierarchies. At the same time, however, the process of becoming a white nation inevitably meant complying with and reproducing racial hierarchies, rather than simply abolishing them.

Visions of Past Glory: Nationalism and the Construction of Early Finnish History

The study is an examination of how the distant national past has been conceived and constructed for Finland from the mid-sixteenth century to the Second World War. The author argues that the perception and need of a national 'Golden Age' has undergone several phases during this period, yet the perceived Greatness of the Ancient Finns has been of great importance for the growth and development of the fundamental concepts of Finnish nationalism. It is a question reaching deeper than simply discussing the Kalevala or the Karelianism of the 1890s. Despite early occurrences of most of the topics the image-makers could utilize for the construction of an Ancient Greatness, a truly national proto-history only became a necessity after 1809, when a new conceptual 'Finnishness' was both conceived and brought forth in reality. In this process of nation-building, ethnic myths of origin and descent provided the core of the nationalist cause - the defence of a primordial national character - and within a few decades the antiquarian issue became a standard element of the nationalist public enlightenment. The emerging, archaeologically substantiated, nationhood was more than a scholarly construction: it was a 'politically correct' form of ethnic self-imaging, continuously adapting its message to contemporary society and modern progress. Prehistoric and medieval Finnishness became even more relevant for the intellectual defence of the nation during the period of Russian administrative pressure 1890-1905. With independence the origins of Finnishness were militarized even further, although the 'hot' phase of antiquarian nationalism ended, as many considered the Finnish state reestablished after centuries of 'dependency'. Nevertheless, the distant past of tribal Finnishness and the conceived Golden Age of the Kalevala remained obligating. The decline of public archaeology is quite evident after 1918, even though the national message of the antiquarian pursuits remained present in the history culture of the public. The myths, symbols, images, and constructs of ancient Finnishness had already become embedded in society by the turn of the century, like the patalakki cap, which remains a symbol of Finnishness to this day. The method of approach is one of combining a broad spectrum of previously neglected primary sources, all related to history culture and the subtle banalization of the distant past: school books, postcards, illustrations, festive costumes, drama, satirical magazines, novels, jewellery, and calendars. Tracing the origins of the national myths to their original contexts enables a rather thorough deconstruction of the proto-historical imaginary in this Finnish case study. Considering Anthony D. Smith's idea of ancient 'ethnies' being the basis for nationalist causes, the author considers such an approach in the Finnish case totally misplaced.