3,051 research outputs found
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
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
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,
The different dimensions of livelihood impacts of Payments for Environmentals Services (PES) schemes: A systematic review
Through a systematic review of peer-reviewed and grey literature, this paper analyzes evidence of the livelihood impacts of Payments for Environmental Services (PES). Forty-six studies assessed PES livelihood impacts. The assessments presented more positive livelihood impacts than negative ones, focusing on financial benefits. Non-monetary and non-material impacts of PES were largely understudied. Most reviews focused on ES providers, hindering the understanding of broader societal impacts. The review yielded examples where participants lost from their participation or where improvements in one livelihood dimension paralleled deterioration in another. Consequently, we identified key research gaps in: i) understanding the social and cultural impacts of PES, ii) evaluating environmental and economic additionality from improving other ES at the expense of cultural ones, iii) and assessing PES impacts in terms of trade-offs between multiple livelihood dimensions. Moreover, increased knowledge is needed on the impact of PES on changes in household expenditure and choice, and on trade-offs between household income and inequality in ES provider communities. Finally, if PES schemes are implemented to sustainably improve livelihoods, targeting disaggregated populations, understanding equity and social power relations within and between ES providers and users, and better monitoring and evaluation systems that consider locally relevant livelihood dimensions are needed
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
Northern Hemisphere Glaciation during the Globally Warm Early Late Pliocene
The early Late Pliocene (3.6 to ~3.0 million years ago) is the last extended interval in Earth's history when atmospheric CO2 concentrations were comparable to today's and global climate was warmer. Yet a severe global glaciation during marine isotope stage (MIS) M2 interrupted this phase of global warmth ~3.30 million years ago, and is seen as a premature attempt of the climate system to establish an ice-age world. Here we propose a conceptual model for the glaciation and deglaciation of MIS M2 based on geochemical and palynological records from five marine sediment cores along a Caribbean to eastern North Atlantic transect. Our records show that increased Pacific-to-Atlantic flow via the Central American Seaway weakened the North Atlantic Current and attendant northward heat transport prior to MIS M2. The consequent cooling of the northern high latitude oceans permitted expansion of the continental ice sheets during MIS M2, despite near-modern atmospheric CO2 concentrations. Sea level drop during this glaciation halted the inflow of Pacific water to the Atlantic via the Central American Seaway, allowing the build-up of a Caribbean Warm Pool. Once this warm pool was large enough, the Gulf Stream–North Atlantic Current system was reinvigorated, leading to significant northward heat transport that terminated the glaciation. Before and after MIS M2, heat transport via the North Atlantic Current was crucial in maintaining warm climates comparable to those predicted for the end of this century
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