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Sexual risk-taking during travel abroad - a cross-sectional survey among youth in Q2 Sweden

Summary Background: The aim was to assess sexual risk-taking behaviour in a sample of Swedish youth who were sexually active while travelling abroad and to examine possible associations with sexual risk-taking behaviour during such travel.Methods: From a population-based sample of 2189 Swedes 18e29 years 768 who were sexually active while abroad, were assessed by a questionnaire concerning socio-dSummary Background: The aim was to assess sexual risk-taking behaviour in a sample of Swedish youth who were sexually active while travelling abroad and to examine possible associations with sexual risk-taking behaviour during such travel.Methods: From a population-based sample of 2189 Swedes 18e29 years 768 who were sexually active while abroad, were assessed by a questionnaire concerning socio-d

Insurance in European VAT : On the Current and Preferred Treatment in the Light of the New Zealand and Australian GST Systems

Whether and how to tax insurance, one of the crucial elements of the modern economy and society, is a complex issue for the design of laws on value added tax (VAT). Exemption from VAT has been the most common international practice, and it is also applied in the harmonized system of European VAT. New Zealand and Australia are examples of legal systems in which an alternative to exemption, a full t

Amyloid-like ribbons of amelogenins in enamel mineralization

Enamel, the outermost layer of teeth, is an acellular mineralized tissue that cannot regenerate; the mature tissue is composed of high aspect ratio apatite nanocrystals organized into rods and inter-rod regions. Amelogenin constitutes 90% of the protein matrix in developing enamel and plays a central role in guiding the hierarchical organization of apatite crystals observed in mature enamel. To da

Preparations for retirement in Sweden: Migrant perspectives

Migrants as a group are recognised as being at risk of receiving low retirement pensions. Income over a lifetime is the principle for calculating pension rights. We have interviewed a group of migrants about their retirement preparations. Our results show that there are obstacles that obstruct migrants from entering the Swedish labour market, which will greatly influence future pension rights. The

Johannes Magnus and the Composition of Truth : Historia de omnibus Gothorum Sueonumque regibus

Johannes Magnus (1488–1544) was the last Catholic archbishop of Uppsala to hold residence in Sweden. He was also a historian and wrote a work in Latin about Swedish history that was to gain an unparalleled importance. The work is entitled Historia de omnibus Gothorum Sueonumque regibus, the ‘History of all the Kings of the Goths and the Swedes’. It is arranged as a series of biographies of over 20

Intimate partner violence against women and the Nordic paradox

Nordic countries are the most gender equal countries in the world, but at the same time they have disproportionally high prevalence rates of intimate partner violence (IPV) against women. High prevalence of IPV against women, and high levels of gender equality would appear contradictory, but these apparently opposite statements appear to be true in Nordic countries, producing what could be called

Operability and performance of central (Pilot) stage of an industrial prototype burner

An investigation on the central-pilot stage of a Siemens Industrial Turbomachinery 4th Generation DLE prototype test burner has been performed to understand the emission performance and operability. The core section, which is defined as RPL (Rich premixed lean) plays an important role for full burner combustion operation by stabilizing the main and pilot flames at different operating condition. Op

Modeling population dynamics, landscape structure, and management decisions for controlling the spread of invasive plants

Invasive plants cause substantial economic and environmental damage throughout the world. However, eradication of most invasive species is impossible and, in some cases, undesirable. An alternative is to slow the spread of an invasive species, which can delay impacts or reduce their extent. We identify three main areas where models are used extensively in the study of plant spread and its manageme

Seed terminal velocity, wind turbulence, and demography drive the spread of an invasive tree in an analytical model

Little is known about the relative importance of mechanistic drivers of plant spread, particularly when long-distance dispersal (LDD) events occur. Most methods to date approach LDD phenomenologically, and all mechanistic models, with one exception, have been implemented through simulation. Furthermore, the few recent mechanistically derived spread models have examined the relative role of differe

Avifauna trends following changes in a Mediterranean upland pastoral system

Understanding the relationships between biodiversity and land-use is a key element for the development of effective conservation strategies. We studied a mid-altitude steppe-like area of Southern France, the Causse de Sauveterre, that has been grazed for many centuries. The decrease of human population during the 20th century, particularly since the end of 2nd World War, and the ongoing changes in

Reproductive ecology of Pinus nigra in an invasive population : Individual- and population-level variation in seed production and timing of seed release

Context: The details of fecundity, such as its distribution and timing, can have important consequences for forest dynamics. Aims: We detail two aspects of the reproductive ecology of an exotic population of Pinus nigra in New Zealand. We compare our findings with those reported for P. nigra in southern France and Britain. Methods: We describe variation in fecundity, both within the population and

Integrating ecological knowledge, public perception and urgency of action into invasive species management

Recently Prévot-Julliard and colleagues presented a concept paper on biological conservation strategies using exotic species as a case study. They emphasized the difficulty of integrating conservation into a broad picture that accounts for public perception as well as scientific knowledge. We support this general call for better integration of society in conservation research, but we believe that

Managing agricultural change for biodiversity conservation in a Mediterranean upland

In Europe, land use changes follow public policies, and particularly the Common Agricultural Policy. To predict the effect of policies on agricultural practices, landscape, and ultimately biodiversity, requires understanding of the interactions between social, economic and ecological dynamics at regional scale. We studied by means of prospective scenarios the possible effects of agricultural chang

Area mediated shifts in bird community composition : A study on a fragmented Mediterranean grassland

The effects of habitat fragmentation on birds have often been studied in forest specialist species. Here we aimed at comparing the response of open habitat birds within a range of habitat specialization. The study area was a Mediterranean pseudo-steppe, designated as important for conservation yet fragmented by tree encroachment. We defined bird species dependency on steppe-like habitat by a corre

Effects of disturbance frequency, species traits and resprouting on directional succession in an individual-based model of forest dynamics

Succession theory focuses on the position of species along the shade tolerance gradient and their ability to colonize recently disturbed patches and has for decades overlooked resprouting as a key trait in community patterns. We study how different species traits interact with disturbance frequency to change species dominance in the canopy, focusing on the effects of resprouting ability. We develo

Modelling invasibility in endogenously oscillating tree populations : Timing of invasion matters

The timing of introduction of a new species into an ecosystem can be critical in determining the invasibility (i.e. the sensitivity to invasion) of a resident population. Here, we use an individual-based model to test how (1) the type of competition (symmetric versus asymmetric) and (2) seed masting influence the success of invasion by producing oscillatory dynamics in resident tree populations. W

Symmetric competition causes population oscillations in an individual-based model of forest dynamics

Individual-based modelling is a promising tool for scaling from the individual to the population and community levels that allows a wide range of applied and theoretical approaches. Here, we explore how intra-specific competition affects population dynamics using FORSITE, an individual-based model describing tree-tree interactions in a spatial and stochastic context. We first describe FORSITE desi