PMUs [phasor measurement unit]

In the spring of 1993, a major new 500 kV transmission line was put in service in Northern California. Test engineers initiated a series of artificial short-circuit faults to test the line installation. As an experiment, the steady-state and transient responses of the power system were recorded. During testing of the new California-Oregon Transmission Project (COTP), a PMU was installed at Olinda Substation near Redding, CA, and at Tracy Substation, near San Francisco, CA roughly 320 kilometers apart. PMU (phasor measurement unit) is a new measuring unit that recorded power system voltages and currents at the two substations. The PMUs use a navigational satellite system to synchronize digital sampling at different substations. That summer the data was analysed using modem digital signal processing software. In this article the author compares actual field measurements of the steady-state pre-fault power system angle with a classic relation for calculating real power flow on a transmission line. The agreement between the state-of-the-art measurements and the classic calculations was very close     

Adapting Eimeria tenella to grow in primary chicken kidney cells following repeated passages between cell culture and chickens

The resolving power of displacement chromatography using low-molecular-weight displacers was investigated using a model mixture containing bovine and horse heart cytochrome c. The linear and nonlinear adsorption behavior of these two proteins was examined in cation-exchange chromatography and shown to be quite similar. Furthermore, an analysis of the dynamic affinity of these proteins indicated extremely similar affinities under displacement conditions. Despite the extreme similarities in the adsorption behavior, displacement chromatography using a protected amino acid displacer resulted in excellent separation of the proteins with both high yields and purity. These results indicate that displacement chromatography may be efficacious for a wide variety of difficult protein separation problems.     

Cardiovascular effects produced by microinjection of angiotensins and angiotensin antagonists into the ventrolateral medulla of freely moving rats

In this study we determined the cardiovascular effects produced by microinjection of angiotensin peptides [Angiotensin-(1-7) and Angiotensin II] and angiotensin antagonists (losartan, L-158,809, CGP 42112A. Sar1-Thr8-Ang II, A-779) into the rostral ventrolateral medulla of freely moving rats. Microinjection of angiotensins (12.5-50 pmol) produced pressor responses associated to variable changes in heart rate, usually tachycardia. Unexpectedly, microinjection of both AT1 and AT2 ligands produced pressor effects at doses that did not change blood pressure in anesthetized rats. Conversely, microinjection of Sar1-Thr8-Ang II and the selective Ang-(1-7) antagonist, A-779, produced a small but significant decrease in MAP an HR. These findings suggest that angiotensins can influence the tonic activity of vasomotor neurons at the RVLM. As previously observed in anesthetized rats, our results further suggest a role for endogenous Ang-(1-7) at the RVLM. The pressor activity of the ligands for AT1 and AT2 angiotensin receptor subtypes at the RVLM, remains to be clarified.     

Acidic FGF regulation of hyperproliferation of fibroblasts in human autosomal dominant polycystic kidney disease

Autosomal dominant polycystic kidney disease (ADPKD) is characterized by cystic tubule enlargement and expansion of the interstitium associated with fibrosis. Our previous studies have analyzed the increased proliferation of cystic epithelial cells and this study examines the basis of increased proliferation of interstitial fibroblasts associated with ADPKD disease progression. ADPKD fibroblasts show phenotypic alterations in vitro, have acquired the capacity to grow in soft agar, and show an increased mitogenic response to a variety of growth factors particularly acidic FGF (aFGF). ELISA, Western immunoblot analysis, and immunocytochemistry showed increased aFGF content in ADPKD tissues and fibroblasts in culture, and aFGF was secreted into the extracellular matrix and conditioned medium, respectively. No alterations in aFGF receptor number were found, but Scatchard analysis of 125I-aFGF binding suggested an increased affinity of binding to the low affinity receptor, and covalent cross-linking analysis suggested the presence of novel putative receptors (120 kDa) in ADPKD fibroblasts. Signaling abnormalities were found, since aFGF incubation resulted in the tyrosine phosphorylation of additional substrates, more rapidly and for a more sustained duration in ADPKD fibroblasts than in normal fibroblasts. These findings suggest an important role for acidic FGF in the hyperproliferation of interstitial fibroblasts associated with disease progression in human ADPKD.     

Karen Machover (1902–1996): Obituary.

Memorializes K. Machover, whose most visible contribution to psychology was her research with the human figure drawing and Personality Projection in the Drawing of the Human Figure: A Method of Personality Investigation (1949). She also contributed to social activism, teaching, organizational development, and individual therapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Selective impairments of memory functioning in unmedicated adults with Gilles de la Tourette's syndrome.

Different forms of memory linked to specific brain regions were assessed in unmedicated adults with Gilles de la Tourette's syndrome (TS) and in normal controls of equivalent age and educational attainment. TS patients were impaired on measures of strategic, working, and procedural memory associated with fronto-striatal function. In contrast, their performance was intact on measures of immediate, semantic, and declarative memory associated with temporal-diencephalic functioning. These findings are consistent with radiological evidence of fronto-striatal abnormalities in TS and provide convergent evidence that a fronto-striatal memory system mediates working memory in humans. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Monitoring results of two examples of building integrated PV (BIPV) systems in the UK

This paper presents monitoring results of two examples of building integrated PV system investigated at the School of the Built Environment, University of Nottingham in the UK. One of the systems is installed on an educational building, and consists of a thin film PV façade appropriate for commercial or office suites. The other system is installed on a detached house, and uses crystalline PV roof slates, appropriate for domestic buildings. As the two buildings are significantly different in size, construction and occupancy, the design and selection of the PV system for each was also different. The monitoring investigation has assisted identification of shortfalls in performance and possible explanations have been suggested. The results presented in this paper provide information on the design process, and highlight similarities and differences in the design, installation, performance and economics of the two systems.     

Fibre-optic based confocal scanning microscopy with semiconductor laser excitation and detection

A compact novel form of confocal scanning microscope using a semiconductor laser is described. Confocal operation is ensured by the use of a single mode optical fibre for both launching the light into the microscope and collecting the signal from the object. The collected light is allowed to reenter the laser and the image is detected as a modulation on the signal from the laser power monitor diode.<>