Immune modulation by fish kinetoplastid parasites : a role for nitric oxide

Trypanoplasma borreli and Trypanosoma carassii are kinetoplastid parasites infecting cyprinid fish. We investigated the role of nitric oxide (NO) in immune modulation during T. borreli and T. carassii infection of carp. Phagocytic cells from different organs produced NO and serum nitrate levels increased, demonstrating that T. borreli activates NO production in vivo. In contrast, T. carassii did not induce NO production in vivo and inhibited LPS-induced NO production in vitro. Production of NO was detrimental to the host as T. borreli-infected carp treated with the inducible NO synthase inhibitor aminoguanidine had a higher survival than infected control carp. This detrimental effect can be explained (in part) by the toxicity of NO to cells in vitro as NO inhibited the proliferative response of blood and spleen leukocytes. Head-kidney phagocytes were resistant to the immunosuppressive effects of NO in vitro. The NO-inducing activity of T. borreli may be an adaptation developed to ensure survival and immune evasion in the fish host. Apparently, T. carassii has adopted another strategy by deactivating specific functions of phagocytes. Both strategies may ensure long-term survival of the parasite

Literature review on pickling inhibitors and cadmium electroplating processes

Because introduction of hydrogen during bright-cadmium electroplating of high strength steels causes hydrogen-stress cracking, a program was undertaken to evaluate various processes and materials. Report describes effectiveness of inhibitors for reducing hydrogen absorption by steels

Mathematical methods of linear programming

Thesis (M.A.)--Boston UniversityA complex modern society has presented its managers with the need to solve a variety of optimization problems. The desire to run a firm in such a way that profit is maximized, to schedule bombing runs to inflict a maximum of damage on an opponent consistent with acceptable losses, or to choose an assignment of available personnel which optimizes efficiency are typical examples. Such problems are called programming problems. The unifying idea here is that the limited resources (e.g. factors of production, planes, or personnel) which are available for use may be combined in a large (generally infinite) number of ways. The object is to choose from these possibilities the combination or combinations which will optimize a measure of the effectiveness of the enterprise. Mathematically, the programming problem is stated. [TRUNCATED

Dominos in the dairy: An analysis of transgenic maize in Dutch dairy farming

Isolation distances to limit the risk of cross-pollination from transgenic to nontransgenic crops can severely limit the potential use of transgenic crops through a so-called 'domino effect' where a field of non-transgenic crops limits adoption of transgenic crops not only on plots in its direct vicinity, but also in plots further away as its neighbors are forced to grow the non-transgenic varieties, forcing their neighbors to grow the non-transgenic variety, and so on. The extent to which this effect takes place, however, may depend crucially on the type of farm. For example, dairy farms can use grassland as a buffer between transgenic and conventional maize plots. This article assesses the effects of isolation distances for transgenic maize in dairy farming. A spatially explicit farm model is applied to a region in the Southern Netherlands to identify to what extent a single farmer (who uses non-transgenic maize) can limit other farmers’ potential to grow transgenic maize. The main findings are that 50% or more of the farms in the study area will not affect the potential adoption of transgenic maize by growing conventional maize at all. This result even holds under distance measures of 800m, which is the largest distance implemented by member states of the European Union. When they do have such effects, isolation distances can reduce the benefits from transgenic maize by €5,000 - €6,000, for a considerable part through a domino effect. Large net benefits of transgenic maize may limit the spatial effects as farmers are more willing to relocate maize production to areas where transgenic maize is allowed.Crop Production/Industries, Livestock Production/Industries,

Self-dual vortex-like configurations in SU(2) Yang-Mills Theory

We show that there are solutions of the SU(2) Yang-Mills classical equations of motion in R^4, which are self-dual and vortex-like(fluxons). The action density is concentrated along a thick two-dimensional wall (the world sheet of a straight infinite vortex line). The configurations are constructed from self-dual R^2 x T^2 configurations.Comment: latex2e file. 10 pages 2 figure

A review of the literature on pickling inhibitors and cadmium electroplating processes to minimize hydrogen absorption by ultrahigh-strength steels

Literature review on pickling inhibitors and cadmium electroplating processes to minimize hydrogen absorption by ultrahigh strength steel

A review of the literature on cleaning, pickling, and electroplating processes and relief treatments to minimize hydrogen embrittlement of ultrahigh-strength steels Special report

Cleaning, pickling, and electroplating processes to minimize hydrogen embrittlement of ultrahigh strength steel

A study of hydrogen embrittlement of various alloys Annual summary report, 24 Jun. 1965 - 23 Jun. 1966

Hydrogen embrittlement of alloy cathodically charged and notched tensile metal

Review of literature on hydrogen embrittlement

Hydrogen embrittlement in high strength iron-base and nickel-base alloys and titaniu

Development of nature-oriented dairy farm systems with an optimization model: the case of ‘Farming for Nature’ in ‘de Langstraat’, the Netherlands

‘Farming for Nature’, a relatively new policy instrument being tried out in the Netherlands, is evaluated. The concept has been designed to allow dairy farmers to improve nature conservation on their farms. Under the scheme, no manure, fertilizer, or feed – concentrates or roughage - may be imported into farm systems from external sources. The feasibility of such a self-sustaining system and the conditions required for it to deliver the desired results, are explored with a farm-based linear programming model known as FIONA (Farm based Integrated Optimization Model for Nature and Agriculture). The model is explained and applied to ‘de Langstraat’, a region in southern Netherlands. The results show that levels of production under the ‘Farming for Nature’ regime are dependent upon soil fertility and the proportion of land that is suitable for growing arable crops. If all available land on a dairy farm in the scheme is arable land, then high production levels of up to 7,500 kg milk per hectare can be realized. If only 30% of the farm area is suitable for arable crops, then only lower production levels, of about 6,600 kg milk per hectare can be realized. The scheme has positive ecological effects. Both nature and cultural landscape values may benefit significantly from the concept. Improvement in ecological terms however, carries a price in terms of agricultural income. An average dairy farm adopting the concept of ‘Farming for Nature’ experiences an income loss of approximately € 840 per hectare in the short-run (5-10 years). More important is the observation that the scale of such farms in the short-run might be too small to earn an attractive income for its workers, even when fully compensated according to European Union regulations.nature management, dairy farming system, linear programming, farm-economics, Farm Management, Land Economics/Use,