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The latest results of lead-free BGA solder joints investigations, performed in frame of GreenRoSE Project financed by EC, are presented. In our investigations were used test specimens BGA256r, developed in Warsaw University of Technology (WUT), and TopLine dummy components. Lead - free and lead - containing components were compared. Mechanical tests were performed by cyclic bending on mechanical stand developed in WUT. Thermal shocks are performed according to standards IPC 9701A and EN 62137. In this paper are presented the results of mechanical tests. [ABSTRACT FROM AUTHOR]

Chapter 12 of the book "Handbook of Precision Farming: Principles and Applications" is presented. It offered an overview of the status of site-specific management in various cotton-producing regions of the U.S. Several factors considered in the grouping of major cotton-producing counties within the U.S. Cotton Belt include genotypes grown, planting dates, growing-season lengths, harvest methods, quality of fiber produced, and fiber end use. When evaluating the degree and distribution of soil spatial variability, an effective soil-sampling plan should be developed or adapted.

We study Boolean grammars. We introduce stratified semantics for Boolean grammars. We show, how to check, if a Boolean grammar generates a language according to this semantics. We show, that stratified semantics covers a class of important and natural languages. We introduce a recognition algorithm for Boolean grammars compliant to this semantics. [ABSTRACT FROM AUTHOR]

Excessive generation of reactive oxygen species and reactive nitrogen species in the Alzheimer's disease (AD) brain and the presence of serotonin in the brain regions that are damaged in this disorder may lead to oxidation of serotonin to tryptamine-4,5-dione, which may possess neurotoxic properties. Efforts to detect this dione in brain tissue or cerebrospinal fluid of AD patients have been so far unsuccessful. However, it may be of relevance that the expression of NAD(P)H:quinone oxidoreductase 1 (NQO1), an enzyme that acts to protect against oxidative stress caused by xenobiotic quinones, is localized not only to neurofibrillary tangles in the AD brain but also to the cytoplasm of hippocampal neurons. In contrast, very little NQO1 is present in the same neuronal populations in age-matched controls. The expression of NQO1 in the AD brain not only provides additional support for excessive production of oxygen free radicals but also, possibly, for a role of a quinone such as tryptamine-4,5-dione. [ABSTRACT FROM AUTHOR]