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50 utilities in the United States and Canada responded to a questionnaire survey regarding concerns about nonsinusoidal waveforms in the electric distribution network. Responses regarding instrumentation, definitions, rates, and trends are presented and discussed. Key words: Harmonics, distortion, nonsinusoidal waveforms

Existing definitions for power terms in alternating current systems work well for single-phase and three-phase systems where both voltages and currents are sinusoidal with respect to time. This paper clarifies and proposes definitions for power terms that are practical and effective when voltage and/or currents are distorted and/or unbalanced. It also suggests definitions for measurable values that may be used to indicate the level of distortion and unbalance. Key words: Harmonics, distortion, power definitions, power factor

A numerical HVDC control system operating in real time has been developed for a simulator to be used for operator training. The control system, implemented with digital signal processors (DSPs), consists of typical HVDC control functions such as the synchronizing unit, the regulation unit, the protection unit, the firing unit, the tap changer and the reactive power regulation unit. Results from the steady-state and the transient performance validation tests carried out on the IREQ power system simulator are provided. Keywords: HVDC controls, Digital Signal Processors, parallel processing.

NEW YORK CITY'S Metropolitan Transportation Authority (MTA) called the devastation and flooding during last fall's Hurricane Sandy the biggest disaster the subway system had ever endured, At the first post-storm [...]

The Canadian Experiment for Soil Moisture in 2010 (CanEx-SM10) was carried out in Saskatchewan, Canada, from 31 May to 16 June, 2010. Its main objective was to contribute to Soil Moisture and Ocean Salinity (SMOS) mission validation and the prelaunch assessment of the proposed Soil Moisture Active and Passive (SMAP) mission. During CanEx-SM10, SMOS data as well as other passive and active microwave measurements were collected by both airborne and satellite platforms. Ground-based measurements of soil (moisture, temperature, roughness, bulk density) and vegetation characteristics (leaf area index, biomass, vegetation height) were conducted close in time to the airborne and satellite acquisitions. Moreover, two ground-based in situ networks provided continuous measurements of meteorological conditions and soil moisture and soil temperature profiles. Two sites, each covering 33 km × 71 km (about two SMOS pixels) were selected in agricultural and boreal forested areas in order to provide contrasting soil and vegetation conditions. This paper describes the measurement strategy, provides an overview of the data sets, and presents preliminary results. Over the agricultural area, the airborne L-band brightness temperatures matched up well with the SMOS data (prototype 346). The radio frequency interference observed in both SMOS and the airborne L-band radiometer data exhibited spatial and temporal variability and polarization dependency. The temporal evolution of the SMOS soil moisture product (prototype 307) matched that observed with the ground data, but the absolute soil moisture estimates did not meet the accuracy requirements (0.04 m3/m3) of the SMOS mission. AMSR-E soil moisture estimates from the National Snow and Ice Data Center more closely reflected soil moisture measurements. [ABSTRACT FROM PUBLISHER]

Carotenoids, especially lutein and beta-carotene, offer benefits to human health in general and to eye health in particular. However, more data on the contribution of plant foods to carotenoid intake is of importance for developing strategies for promoting eye health in regions where cataract is highly prevalent such as in South India. The most frequently consumed 5 uncultivated and 5 commercially grown South Andhra Pradesh leafy vegetables were selected based on interviews with 100 local women. The lutein and beta-carotene contents of fresh and cooked samples were determined using reversed-phase high performance liquid chromatography. Lutein values ranged from 53 to 143 mug/g and 58 to 175 mug/g in fresh and cooked samples, respectively. beta-carotene contents were found to range from 45 to 119 mug/g in fresh samples and from 40 to 159 mug/g in cooked samples. No significant difference was observed between the carotenoid contents of wild and commercially grown species. According to their reported frequency of consumption, the 10 species considered in this study contribute 40% of the daily recommended intake of beta-carotene. This is the first report of lutein content in fresh samples of Celosia argentea L., Rumex vesicarius L., Digera muricata (L.) Mart., and Amaranthus cruentus L. as well as in cooked samples of all species included in this study. [ABSTRACT FROM AUTHOR]

Background: Addison's disease, also known as hypoadrenocorticism, has been reported in many individual dogs, although some breeds exhibit a greater incidence than the population as a whole. Addison's is presumed to be an autoimmune mediated hereditary defect but the mode of inheritance remains unclear. In particular, the heritability and mode of inheritance have not been defined for the Portuguese Water Dog although Addison's is known to be prevalent in the breed. Results: The analyses present clear evidence that establishes Addison's disease as an inherited disorder in the Portuguese Water Dog with an estimate of heritability of 0.49 (± 0.16); there were no differences in risk for disease across sexes (p > 0.49). Further, the complex segregation analysis provides suggestive evidence that Addison's disease in the Portuguese Water Dog is inherited under the control of a single, autosomal recessive locus. Conclusion: The high heritability and mode of inheritance of Addison's disease in the Portuguese Water Dog should enable the detection of segregating markers in a genome-wide scan and the identification of a locus linked to Addison's. Though the confirmation of Addison's disease as an autosomal recessive disorder must wait until the gene is identified, breeders of these dogs may wish to keep the present findings in mind as they plan their breeding programs to select against producing affected dogs. [ABSTRACT FROM AUTHOR]