Generation, flow and utilisation of information on the regional fish trade

The purpose of the study was to provide an in-depth understanding of information generation, flow and utilization within Uganda’s regional fish trade. The study was carried out at district headquarters, border points, landing sites and border markets, involving DFOs, Customs Officials, BMU executives and market managers.

Perspectives of impacts of international fish trade in Kenya

There has been tremendous growth in international trade on fish and fisheries products in the last four decades. In 1970 the value of internationally traded fish was estimated at 3 billion; this increased to US$ 15 billion in 1980, US$ 36 billion in 1990 and US$ 55 billion in 2000 (Ahmed, 2003). Recent statistics show that fish trade has surpassed other agricultural commodities that have traditionally been traded internationally such as coffee, tea, cocoa, sugar, cereals, meat, oils and milk. In 2000, fish contributed 22% of the value of all agricultural exports, making it the highest internationally traded food product (Ahmed, 2003). In another perspective, nearly 40% of the world's fish is now sold in the international market. The flow of fish in the international market is highly lopsided. About 50% of fish exportscomefromthedevelopingworld ,ofwhich 20%arefrom low-incomefood deficient countries. Most of this fish, however, is consumed by the developed countries, which account for nearly 80% of all imported fish. The EU, USA and Japan are the major importers, accounting for over 77% of global fish imports. Thus, while developing countries playa big role in fish production , they consume very little of it, instead preferring to sell for the hard currency. In some fish exporting countries, especially those in Asia, there is some link between fish exports and imports of substitute and complementary foods. Much of the increased earning from fish exports in those countries is explained by a corresponding rise in expenditure on imported foods. This is not the case in many of the fish exporter nations in Africa. In their case, fish exports generate foreign exchange that they use to meet other socio-political objectives; hardly is it aimed at solving the wider food needs. Therefore, one of the most immediate concerns of international fish trade is its impact on food security in the poor exporter nations.

Observations on the biology of Nothobranchius guentheri (Pfeffer) (Cyprinodontidae), an annual fish from the coastal region of East Africa

Nothobranchius guntheri is found in seasonal pools and streams in the coastal region of Tanzania. A population recurring annually in a pond near Kilosa has been studied. Growth in length was rapid and maximum mean lengths were attained within 11-12 and 7-8 weeks of hatching by males and females respectively. Males grew larger and exhibited wider variation in length than females. N. guentheri shows clear sexual dichromatism. No significant inequality in the sex ratio was found. Females with ripe eggs were found 7-8 weeks after hatching. Spawning continued throughout adult life and fecundity increased markedly with increasing length. In laboratory aquaria, aggressiveness between adult males was noted and females were actively driven on to the substratum preparatory to spawning. The diet of the fish pond consisted chiefly of aquatic and terrestrial insects, of which midge larvae and pupae were the most common. N. guentheri is exploited by man in the aquarist trade and for the biological control of mosquitoes. An extended redescription of the species is appended which includes N. melanospilus (Pfeffer) as a synonym.

Branching toughens fibrous networks.

Fibrous collagenous networks are not only stiff but also tough, due to their complex microstructures. This stiff yet tough behavior is desirable for both medical and military applications but it is difficult to reproduce in engineering materials. While the nonlinear hyperelastic behavior of fibrous networks has been extensively studied, the understanding of toughness is still incomplete. Here, we identify a microstructure mimicking the branched bundles of a natural type I collagen network, in which partially cross-linked long fibers give rise to novel combinations of stiffness and toughness. Finite element analysis shows that the stiffness of fully cross-linked fibrous networks is amplified by increasing the fibril length and cross-link density. However, a trade-off of such stiff networks is reduced toughness. By having partially cross-linked networks with long fibrils, the networks have comparable stiffness and improved toughness as compared to the fully cross-linked networks. Further, the partially cross-linked networks avoid the formation of kinks, which cause fibril rupture during deformation. As a result, the branching allows the networks to have stiff yet tough behavior.

Product life trade-offs: what if products fail early?

Increasing product life allows the embodied emissions in products to be spread across a longer period but can mean that opportunities to improve use-phase efficiency are foregone. In this paper, a model that evaluates this trade-off is presented and used to estimate the optimal product life for a range of metal-intensive products. Two strategies that have potential to save emissions are explored: (1) adding extra embodied emissions to make products more sturdy, increasing product life, and (2) increasing frequency of use, causing early product failure to take advantage of improvements in use-phase efficiency. These strategies are evaluated for two specific case studies (long-life washing machines and more frequent use of vehicles through car clubs) and for a range of embodied and use-phase intensive products under different use-phase improvement rate assumptions. Particular emphasis is placed on the fact that products often fail neither at their design life nor at their optimal life. Policy recommendations are then made regarding the targeting of these strategies according to product characteristics and the timing of typical product failure relative to optimal product life.

Design trade-offs for energy regeneration and control in vehicle suspensions

This paper investigates the fundamental trade-offs involved in designing energy-regenerative suspensions, in particular, focusing on efficiency of power extraction and its effect on vehicle dynamics and control. It is shown that typical regenerative devices making use of linear-to-rotational elements can be modelled as a parallel arrangement of an inerter and a dissipative admittance. Taking account of typical adjustable parameters of the generator, it is shown, for a given suspension damping coefficient, that the power efficiency ratio scales with inertance. For a typical passenger vehicle, it is shown that there is a feasible compromise, namely that good efficiency is achievable with an inertance value that is not detrimental to vehicle performance. A prototype is designed and tested with a resistive termination and experimental results show good agreement between ideal and experimental admittances. The possibility to use dynamic (rather than purely resistive) loads to improve vehicle control without limiting the energy recovery is discussed. © 2013 Copyright Taylor and Francis Group, LLC.

Optimization of Global Signal Networks for Island-Style FPGAs

We present a staggered buffer connection method that provides flexibility for buffer insertion while designing global signal networks using the tile-based FPGA design methodology. An exhaustive algorithm is used to analyze the trade-off between area and speed of the global signal networks for this staggered buffer insertion scheme, and the criterion for determining the design parameters is presented. The comparative analytic result shows that the methods in this paper are proven to be more efficient for FPGAs with a large array size.

Red-light-emitting iridium complexes with hole-transporting 9-arylcarbazole moieties for electrophosphorescence efficiency/color purity trade-off optimizationE

The synthesis, structures, photophysics, electrochemistry and electrophosphorescent properties of new red phosphorescent cyclometalated iridium(III) isoquinoline complexes, bearing 9-arylcarbazolyl chromophores, are reported. The functional properties of these red phosphors correlate well with the results of density functional theory calculations

Red-Light-Emitting Iridium Complexes with Hole-Transporting 9-Arylcarbazole Moieties for Electrophosphorescence Efficiency/ Color Purity Trade-off Optimization

The synthesis, structures, photophysics, electrochemistry and electrophosphorescent properties of new red phosphorescent cyclometalated iridium(III) isoquinoline complexes, bearing 9-arylcarbazolyl chromophores, are reported. The functional properties of these red phosphors correlate well with the results of density functional theory calculations. The highest occupied molecular orbital levels of these complexes are raised by the integration of a carbazole unit to the iridium isoquinoline core so that the hole-transporting ability is improved in the resulting complexes relative to those with I-phenylisoquinoline ligands. All of the complexes are highly thermally stable and emit an intense red light at room temperature with relatively short lifetimes that are beneficial for highly efficient organic light-emitting diodes (OLEDs).

Duplicating "sunlight'' from simple WOLEDs for lighting applications

Simple single-dopant white organic light-emitting devices (WOLEDs) with optimized efficiency/color quality/brightness trade-offs are developed; the white light produced shows the best color quality ever exhibited by WOLEDs at very high brightness, and is even able to duplicate the natural sunlight source.