Improving productivity in tropical lakes and reservoirs

Freshwater aquaculture, Inland fisheries

Migration eller mobilitet — et kunstigt skel med praktiske konsekvenser

M igration eller mobilitet-det, som på overfladen blot ligner en terminologisk skelnen mellem migration og mobilitet, dækker i virkeligheden over en væsentlig forskellig opfattelse af det samme fænomen betinget af, om migranterne kommer fra lande inden for eller uden for EU/E¯S. Den forskel betyder bla., at migranterne fra EU/E¯S ses i et arbejdsmarkedsperspektiv, hvor de tilskrives en midlertidighed, mens migranter fra lande uden for EU/E¯S ses i et bredere samfundsperspektiv, hvor de tilskrives en mere permanent karakter. Disse grundlæggende forskellige opfattelser stemmer ikke altid overens med, hvordan de forskellige grupper i virkeligheden agerer, men har ikke desto mindre en række praktiske konsekvenser for både migranterne og samfundet

Balanced exploitation and coexistence of interacting, size-structured, fish species

This paper examines some effects of exploitation on a simple ecosystem containing two interacting fish species, with life histories similar to mackerel (Scomber scombrus) and cod (Gadus morhua), using a dynamic, size-spectrum model. Such models internalize body growth and mortality from predation, allowing bookkeeping of biomass at a detailed level of individual predation and growth and enabling scaling up to the mass balance of the ecosystem. Exploitation set independently for each species with knife-edge, size-at-entry fishing can lead to collapse of cod. Exploitation to achieve a fixed ratio of yield to productivity across species can also lead to collapse of cod. However, harvesting balanced to the overall productivity of species in the exploited ecosystem exerts a strong force countering such collapse. If balancing across species is applied to a fishery with knife-edge selection, size distributions are truncated, changing the structure of the system and reducing its resilience to perturbations. If balancing is applied on the basis of productivity at each body size as well as across species, there is less disruption to size-structure, resilience is increased, and substantially greater biomass yields are possible. We note an identity between the body size at which productivity is maximized and the age at which cohort biomass is maximized. In our numerical results based on detailed bookkeeping of biomass, cohort biomass reaches its maximum at body masse

Engaging local communities in aquatic resources research and activities: a technical manual

This document is part of a series of 5 technical manuals produced by the Challenge Program Project CP34 “Improved fisheries productivity and management in tropical reservoirs”. The objective of this technical manual is to relay the field experience of a group of scientists who have worked extensively in small fisheries in sub-Sahara Africa and Asia and lay out a series of simple and pragmatic pointers on how to establish and run initiatives for community catch assessment. The manual relies in particular on practical experience gained implementing Project 34 of the Challenge Programme on Water and Food: Improved Fisheries Productivity and Management in Tropical Reservoirs. (PDF contains 26 pages

Storytelling in Focus Group Discussions: A Narrative Approach to Phenomena With Temporal Dimensions in Medical Education Research

People can express experiences, opinions, and perspectives in stories. In a story, the experiences can be relived and discovered independently of time and place. In medical education, it is a fundamental premise that time progresses, and it is within this temporal space that students learn, acquire competencies, and form identity. It is also within this space that much qualitative research is conducted. However, qualitative examinations at one point in time will result in only a snapshot of a dynamic phenomenon that evolves over time. Existing approaches to qualitative research are often inadequate to accommodate this dynamic development without applying a time- and cost-consuming design such as longitudinal investigations. The purpose of this paper is to present storytelling as a useful research approach to include temporal dimensions in cross-sectional qualitative data collection. We describe the background for the approach, argue for its use, and provide a practical example of storytelling with the use of a fictional character in online focus group discussions to explore a dynamic phenomenon in medical education research. Overall, storytelling offers a narrative approach to qualitative research that allows the researcher to explore phenomena across time and space. The approach has the advantage that it can be used in different formats both oral and written, digital or physical.</p

A division of labour? Labour market segmentation by region of origin: the case of intra-EU migrants in the UK, Germany and Denmark

The 2004/2007 EU enlargements rendered CEE citizens legally equal to EU labour market participants. However, CEE migrants still face ‘racialisation’ and segmentation in North-Western European labour markets. Similar processes might extend to EU-South migrants, giving rise to a division of labour, whereby CEE and EU-South migrants end up in poor-quality, low-pay jobs. We compare the labour market integration of recent intra-EU migrants (EU8, EU2, EU-South, EU-West/EEA) in the UK, Germany and Denmark. Using labour force, microcensus and register data, we model quantitative and qualitative integration through labour force participation and wages. We find no significant differences in labour force participation between nationals and migrants in the UK. Whilst in both Denmark and Germany, the labour force participation of EU-migrants is significantly lower. Notwithstanding differences in migration trends, labour markets and welfare regimes, we find evidence of a division of labour along occupational and industry lines − that translates into wage differences. EU-West/EEA migrants occupy better jobs (even outperforming nationals), followed by EU-South and CEE migrants. In Denmark and Germany, EU8 and EU2 migrants’ wages are lower than those of nationals even after controlling for differences in occupations. These findings suggest that inequalities across the EU are reproduced rather than converging

Use of high resolution simulations for training development

This thesis outlines the use of the Training- Modeling Integration TM-1 process for development of training information. High resolution simulations portray weapon system operations in sufficient detail for the training developer to use the simulation to formulate task information and training insights. Training developers have relied heavily on observable information for developing training. Through the use of the TM-1 process, training developers can now use high resolution simulations to observe system employment and operation. Straightforward data analysis techniques are used to analyze simulation derived data files. The unique nature of this methodology is embodied in the synthesis of training development needs, analytical techniques and high resolution simulation data.http://archive.org/details/useofhighresolut00koldMajor, United States ArmyApproved for public release; distribution is unlimited