Study on conductivity and redox stability of iron orthovanadate

FeVO₄ was synthesised by conventional solid state technique. Impedance measurements using a silver electrode were unsuccessful due to a solid state reaction between FeVO₄ and Ag, forming α-AgVO₃ and α-Fe₂O₃ at the interface. Impedance measurements, with a platinum electrode, reaffirmed that FeVO₄ exhibits semiconductor behaviour in air. In a reducing atmosphere, 5% H₂/Ar, high electronic conductivity, from 1 S cm⁻¹ at 300 °C to 2 S cm⁻¹ at 700 °C, was observed with an activation energy of 0.13(1) eV. X-ray diffraction, thermogravimetric analysis and differential scanning calorimetry data determined that the change in electronic conductivity was due to the degradation of the material into FeV₂O₄ and α-Fe₂O₃. It is believed that the conduction was due to electron hopping between vanadium d-orbitals. Neither FeVO₄ nor FeV₂O₄ are deemed suitable as anode materials for solid oxide fuel cells, due to redox instability.     

Identifying the components

Most, if not all, databases are mixtures of samples from different distributions. Transactional data is no exception. For the prototypical example, supermarket basket analysis, one also expects a mixture of different buying patterns. Households of retired people buy different collections of items than households with young children. Models that take such underlying distributions into account are in general superior to those that do not. In this paper we introduce two MDL-based algorithms that follow orthogonal approaches to identify the components in a transaction database. The first follows a model-based approach, while the second is data-driven. Both are parameter-free: the number of components and the components themselves are chosen such that the combined complexity of data and models is minimised. Further, neither prior knowledge on the distributions nor a distance metric on the data is required. Experiments with both methods show that highly characteristic components are identified.     

Operational maintenance data for power generation distribution andHVAC components

This paper describes the culmination of a 24000-man-hour effort to collect operational and maintenance data on 239 power generation, power distribution and heating, ventilation and air conditioning items, including gas turbine generators, diesel engine generators, switchgear assemblies, cables, boilers, piping, valves and chillers. This program was designed to determine the effects of “new technology” equipment, i.e., equipment installed after 1971, on availability. The central hypothesis was that this new equipment would exhibit a significant increase in availability, with corresponding decreases in required maintenance and the occurrence of failures. Information was obtained on a variety of commercial and industrial facility types (including office buildings, hospitals, water treatment facilities, prisons, utilities, manufacturing facilities, schools, universities, and bank computer centers), with varying degrees of maintenance quality. Data collection guidelines and goals were established to ensure that sufficient operational and maintenance data were collected for statistically valid analysis     

Rod outer segment maintenance is enhanced in the presence of bFGF, CNTF and GDNF

We employed a morphological assay of outer segment collapse to determine if growth factors or other supplements directly affect dissociated rod photoreceptors in vitro. The morphological changes in outer segments were correlated with the light responsiveness of rods. Time-lapse video microscopy was used to observe the collapse of rod outer segments from isolated single cells and small clumps of cells. A consistent pattern of outer segment collapse into the inner segment was observed, yielding a convenient assay of the effects of neurotrophic factors on photoreceptor functional maintenance. The functional state of rods, defined as light-responsiveness, was measured with suction electrode recordings and matched with the various stages of outer segment collapse. Ciliary neurotrophic factor (CNTF) and glial cell-line-derived neurotrophic factor (GDNF) at a high concentration, yielded statistically significant improvements in rat outer segment survival times. Basic fibroblast growth factor (bFGF), which rescues photoreceptors in several rodent models of retinal degeneration, produced a significant increase in survival time in the presence of the cofactor heparin. In 4 out of 10 cases using human tisue, bFGF also yielded a significant increase in survival times. When brain-derived neurotrophic factor (BDNF) was applied to rat rods, outer segment survival times did not change. Outer segments collapsed more quickly when either pigment epithelial cell derived factor (PEDF) or sugar N-acetyl D-galactosamine (NAD-gal) were present. Our results show that rod photoreceptors can respond to bFGF, GDNF and CNTF in vitro and provide evidence for a direct effect of these neurotrophic factors on rods. The rapid collapse of isolated photoreceptors in this model provides a convenient means for testing various neurotrophic agents and the induced cellular responses.     

砖石建筑过时了吗？

人们说，车轮是人类最伟大的发明。当然很难就此争论其是与非。但是处于第二位的是什么呢？可能不起眼的砖块是竞选者之一。它体积之小，可握于手中，但是数块砖叠砌在一起又是如此的巨大，在太空上用肉眼就可以看到用它们所建造的建筑。诚然，虽说中国的万里长城并不是每一部分都由烧制砖块砌成，但是大部分采用了这种材料。尤其是墙的顶部用灰泥嵌缝并结合恰当，这样就不会有植物从中长出来了。     

The effects of antipsychotic medication on sequential inhibitory processes.

The authors used a Stroop negative priming paradigm to examine the effects of antipsychotic medication on selective attentional processes. The performance of 14 patients with schizophrenia who were withdrawn from neuroleptic medication was compared with that of 10 medicated patients and 16 matched controls. Results demonstrated an increase in negative priming to normal levels with neuroleptic therapy. In contrast, within-trial interference and facilitation effects appeared to be less sensitive to medication therapy. The sustainment of inhibitory processes over time may differentiate the inhibitory mechanisms of the medication-withdrawn patients from both the medicated patients and the matched controls. The study of sequential inhibitory processes and their response to neuroleptic treatment could be important methods for understanding the temporal parameters associated with inhibition in schizophrenia. (PsycINFO Database Record (c) 2010 APA, all rights reserved)