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A new efficient algorithm is presented for joint diagonalization of several matrices. The algorithm is based on the Frobenius-norm formulation of the joint diagonalization problem, and addresses diagonalization with a general, non- orthogonal transformation. The iterative scheme of the algorithm is based on a multiplicative update which ensures the invertibility of the diagonalizer. The algorithm's efficiency stems from the special approximation of the cost function resulting in a sparse, block-diagonal Hessian to be used in the computation of the quasi-Newton update step. Extensive numerical simulations illustrate the performance of the algorithm and provide a comparison to other leading diagonalization methods. The results of such comparison demonstrate that the proposed algorithm is a viable alternative to existing state-of-the-art joint diagonalization algorithms. The practical use of our algorithm is shown for blind source separation problems
Polymeric electrophosphorescent LEDs with internal quantum efficiencies approaching unity have been fabricated. Such performance levels are previously unknown for OLEDs. The key to this success is redox chemically doped oxetane- crosslinkable hole-transporting layers with multilayer capability (see figure). They improve hole injection and act as electron-blocking layers, without the need to include exciton-or hole-blocking layers
Independent component analysis of noninvasively recorded cortical magnetic DC-fields in humans
(2000)
Indicators to assess sustainable land development often focus on either economic or ecologic aspects of landscape use. The concept of multifunctional land use helps merging those two focuses by emphasising on the rule that economic action is per se accompanied by ecological utility: commodity outputs (CO, e.g., yields) are paid for on the market, but non-commodity outputs (NCO, e.g., landscape aesthetics) so far are public goods with no markets. Agricultural production schemes often provided both outputs by joint production, but with technical progress under prevailing economic pressure, joint production increasingly vanishes by decoupling of commodity from non-commodity production. Simultaneously, by public and political awareness of these shortcomings, there appears a societal need or even demand for some non-commodity outputs of land use, which induces a market potential, and thus, shift towards the status of a commodity outputs. An approach is presented to merge both types of output by defining an indicator of social utility (SUMLU): production schemes are considered with respect to social utility of both commodity and non-commodity outputs. Social utility in this sense includes environmental and economic services as long as society expresses a demand for them. For each combination of parameters at specific frame conditions (e.g., soil and climate properties of a landscape) a production possibility curve can reflect trade-offs between commodity and non-commodity outputs. On each production possibility curve a welfare optimum can be identified expressing the highest achievable value of social utility as a trade-off between CO and NCO production. When applying more parameters, a cluster of welfare optimums is generated. Those clusters can be used for assessing production schemes with respect to sustainable land development. Examples of production possibility functions are given on easy applicable parameters (nitrogen leaching versus gross margin) and on more complex ones (biotic integrity). Social utility, thus allows to evaluate sustainability of land development in a cross-sectoral approach with respect to multifunctionality. (C) 2005 Elsevier Ltd. All rights reserved
Birth weight variation is influenced by fetal and maternal genetic and non-genetic factors, and has been reproducibly associated with future cardio-metabolic health outcomes. In expanded genome-wide association analyses of own birth weight (n = 321,223) and offspring birth weight (n = 230,069 mothers), we identified 190 independent association signals (129 of which are novel). We used structural equation modeling to decompose the contributions of direct fetal and indirect maternal genetic effects, then applied Mendelian randomization to illuminate causal pathways. For example, both indirect maternal and direct fetal genetic effects drive the observational relationship between lower birth weight and higher later blood pressure: maternal blood pressure-raising alleles reduce offspring birth weight, but only direct fetal effects of these alleles, once inherited, increase later offspring blood pressure. Using maternal birth weight-lowering genotypes to proxy for an adverse intrauterine environment provided no evidence that it causally raises offspring blood pressure, indicating that the inverse birth weight-blood pressure association is attributable to genetic effects, and not to intrauterine programming.
The transmembrane tight junction protein occludin is sensitive to oxidative stress. Occludin oligomerizes; however, its function in the tight junction is unknown. The cytosolic C-terminal tail contains a coiled coil-domain and forms dimers contributing to the oligomerization. The regulation of the oligomerization remains unclear. As the domain area contains sulfhydryl residues, we tested the hypothesis that the dimerization of the coiled coil-domain depends on these residues. We showed that the dimerization is modulated by the thiol concentration in the low-millimolar range, which is relevant both for physiological and pathophysiological conditions. Masking the sulfhydryl residues in the fragment by covalent binding of 4-vinyl pyridine prevented the dimerization but did not affect its helical structure and cylindric shape. The data demonstrate, for the first time, that disulfide bridge formation of murine cystein 408 is involved in the dimerization. This process is redox-sensitive but the secondary structure of the domain is not. It is concluded that the dimerization of occludin may play a regulatory role in the tight junction assembly under physiological and pathological conditions.