InGaAsP 400*200 mu m active crosspoint switch operating at 1.5 mu m using novel reflective Y-coupler components

The fabrication and operating characteristics of an active crosspoint switch with an overall dimension of 400*200 mu m is reported. The device can operate with no net loss, and unity facet to facet gain was demonstrated for both bar and cross state operation.<>     

Antisense estrogen receptor RNA expression increases epidermal growth factor receptor gene expression in breast cancer cells

In human breast cancer, progression to a more malignant phenotype is often accompanied by decreased expression of estrogen receptor (ER) and increased expression of epidermal growth factor receptor (EGFR). Higher levels of this receptor tyrosine kinase are found in tumors lacking ER, and a quantitative, inverse relationship exists between the level of ER and EGFR mRNA in human breast cell lines. Antisense ER (ASER) RNA was used to evaluate the consequence of decreased ER expression in breast cancer cells, specifically to determine whether ER is involved in the regulation of EGFR gene expression. ER-positive MCF-7 human breast cancer cells were transfected with ASER, and clones constitutively expressing ASER RNA had decreased ER and up to a 3-fold increase in the expression of EGFR mRNA. To confirm that this observation was a direct consequence of ASER expression, a metal-inducible ASER expression construct was transfected into MCF-7 cells, and transfected clones were isolated and characterized. Northern analysis revealed an induction of ASER RNA within 1 h of the addition of zinc, which was followed by a 4-fold increase in EGFR mRNA levels, maximal at 6-12 h. The basal level of expression of the glucocorticoid receptor is also inversely related to that of ER among breast cancer cell lines, but neither constitutive nor inducible expression of ASER affected the expression of glucocorticoid receptor. These data support the hypothesis that the level of expression of ER specifically influences the expression of EGFR in human breast cancer cells and provides a potential link between loss of steroid sensitivity and the acquisition of autonomous growth.     

The role of the industrial engineer in developing expert systems

The most popular area of Artificial Intelligence application today is in expert systems. This paper contains a discussion of expert systems, otherwise known as knowledge-based systems and knowledge systems. The principal components of an expert system, and the evolution of expert systems are presented. The suitability of a task to an expert system is proposed. When a task is suitable for an expert system application, the system must be developed by a knowledge engineer. The methodology that the knowledge engineer must go through to develop an expert system is demostrated. Industrial engineers have formal training in many areas which can be useful when assumming the role of knowledge engineer. These areas of industrial engineering and how they are beneficial is discussed. What the future may hold in store is also pondered.     

Effects of bioaugmentation on indigenous PCB dechlorinating activity in sediment microcosms

Bioaugmentation is an attractive mechanism for reducing recalcitrant pollutants in sediments, especially if this technology could be applied in situ. To examine the potential effectiveness of a bioaugmentation strategy for PCB contamination, PCB dehalorespiring populations were inoculated into Baltimore Harbor sediment microcosms. A culture containing the two most predominant indigenous PCB dehalorespiring microorganisms and a culture containing a strain with a rare ortho dechlorination activity and a non-indigenous strain that attacks double-flanked chlorines, were inoculated into sediment microcosms amended with 2,2′,3,5,5′,6-hexachlorobiphenyl (PCB 151) and Aroclor 1260. Although we observed a similar reduction in the concentration of PCB 151 in all microcosms at day 300, a reduced lag time for dechlorination activity was observed only in the bioaugmented microcosms and the pattern of dechlorination was altered depending on the initial combination of microorganisms added. Dechlorination of Aroclor 1260 was most extensive when dehalorespiring microorganisms were added to sediment. Overall numbers of dehalorespiring microorganisms in both bioaugmented and non-bioaugmented microcosms increased 100- and 1000-fold with PCB 151 and Aroclor 1260, respectively, and they were sustained for the full 300 days of the experiments. The ability of bioaugmentation to redirect dechlorination reactions in the sediment microcosms indicates that the inoculated PCB dehalorespiring microorganisms effectively competed with the indigenous microbial populations and cooperatively enhanced or altered the specific pathways of PCB dechlorination. These observations indicate that bioaugmentation with PCB dehalorespiring microorganisms is a potentially tractable approach for in situ treatment of PCB impacted sites.     

Recognition memory in depression.

Research suggests that the poor performance of depressed patients on memory tests reflects cautious response criteria rather than reduced accessibility of memories. Studies of recognition memory enable this issue to be addressed. The present experiment provides the first clear demonstration of a deficit in recognition memory in depression that is not explicable in terms of response bias. A subsidiary concern was to examine the effect of requiring subjects to vocalize words on presentation. This had no significant effects on "hits," but it interacted with depression on "false alarms," suggesting that discrepant claims in the literature regarding the effects of depression on false alarms may be attributable to procedural variations. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

CD28-independent, TRAF2-dependent costimulation of resting T cells by 4-1BB ligand

4-1BB ligand (4-1BBL) is a member of the tumor necrosis factor (TNF) family expressed on activated antigen-presenting cells. Its receptor, 4-1BB, is a member of the TNF receptor family expressed on activated CD4 and CD8 T cells. We have produced a soluble form of 4-1BBL using the baculovirus expression system. When coimmobilized on plastic with anti-CD3, soluble 4-1BBL induces interleukin (IL)-2 production by resting CD28+ or CD28- T cells, indicating that 4-1BBL can function independently of other cell surface molecules, including CD28, in costimulation of resting T cell activation. At low concentrations of anti-CD3, 4-1BBL is inferior to anti-CD28 in T cell activation. However, when 4-1BB ligand is provided together with strong TCR signals, then 4-1BBL and anti-CD28 are equally potent in stimulation of IL-2 production by resting T cells. We find that TNF receptor-associated factor (TRAF)1 or TRAF2 associate with a glutathione S-transferase-4-1BB cytoplasmic domain fusion protein in vitro. In T cells, we find that association of TRAF1 and TRAF2 with 4-1BB requires 4-1BB cross-linking. In support of a functional role for TRAF2 in 4-1BB signaling, we find that resting T cells isolated from TRAF2-deficient mice or from mice expressing a dominant negative form of TRAF2 fail to augment IL-2 production in response to soluble 4-1BBL. Thus 4-1BB, via the TRAF2 molecule, can provide CD28-independent costimulatory signals to resting T cells.