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Purpose: The aim of this work is to evaluate a new eight‐channel transceiver (TxRx) coaxial dipole array for imaging of the human head at 9.4T developed to improve specific absorption rate (SAR) performance, and provide for a more compact and robust alternative to the state‐of‐the art dipole arrays. Methods: First, the geometry of a single coaxial element was optimized to minimize peak SAR and sensitivity to the load variation. Next, a multi‐tissue voxel model was used to numerically simulate a TxRx array coil that consisted of eight coaxial dipoles with the optimal configuration. Finally, we compared the developed array to other human head dipole arrays. Results of numerical simulations were verified on a bench and in the scanner including in vivo measurements on a healthy volunteer. Results: The developed eight‐element coaxial dipole TxRx array coil showed up to 1.1times higher SAR‐efficiency than a similar in geometry folded‐end and fractionated dipole array while maintaining whole brain coverage and low sensitivity of the resonance frequency to variation in the head size. Conclusion: As a proof of concept, we developed and constructed a prototype of a 9.4T (400 MHz) human head array consisting of eight TxRx coaxial dipoles. The developed array improved SAR‐efficiency and provided for a more compact and robust alternative to the folded‐end dipole design. To the best of our knowledge, this is the first example of using coaxial dipoles for human head MRI at ultra‐high field. [ABSTRACT FROM AUTHOR]

In the United States, about 90% of drinking water home plumbing systems use copper pipes. Pinhole leaks in copper plumbing pipes have become a concern for the homeowners because such leaks have resulted in property damage, lowered property values, and the possibility of losing their insurance coverage. Homeowners would benefit from tools enabling them to decide on whether to continue to repair or replace their plumbing system, the factors to be considered in a replacement decision, and the type of material to use for replacement. Multiple attributes including price, corrosion resistance, fire retardance, health effects, longevity, resale value of home, and taste and odor are considered in choice of plumbing materials. We formalized 'choosing alternative plumbing materials' within the framework of the analytic hierarchy process. Empirical surveys were administered to 135 students of Civil and Environmental Engineering at Virginia Tech. Survey results show that health effects, taste and odor, longevity, and corrosion resistance are the influential factors when choosing alternative plumbing materials. Health effects and taste and odor of drinking water are surrogates for the purity of water that dominates preferences for a plumbing material. Research results will assist homeowners in making better informed decision regarding their plumbing systems. DOI: 10.1061/(ASCE)0733-9496(2009)135:4(237) CE Database subject headings: Copper: Water pipelines: Drinking water: Plumbing; Case reports; Decision making.

Consumers face numerous problems when they experience leaks and premature failures in their potable drinking water plumbing system. A review of an existing database of copper pipe failures demonstrated that premature pipe failures and pinhole leaks have been documented across the United States. Additionally, there are 'hotspots' in the United States where pinhole failures have been documented to occur at a fairly high incidence. A number of known and suspected factors can cause copper pitting corrosion that eventually develops into a pinhole leak, such as specific water qualities, microbial activity, hydraulics, and other installation factors. However, the current understanding does not adequately define the complex synergy between causal factors, which poses a challenge in assessing plumbing susceptibility and shaping an effective management plan. This work presents a preliminary ranking of the causal factors for assessing plumbing susceptibility. However, due to incomplete understanding of the pinhole phenomenon, advice from local experts and past service history should still be given priority in assessing the likelihood of problems. DOI: 10.1061/(ASCE)0733-9496(2009) 135:4(227) CE Database subject headings: Leakage; Water pipelines; Copper; Plumbing; Remedial action.

Upper Triassic volcanic and sedimentary rocks of the Mamonia Complex in southwestern Cyprus are exposed in erosional windows through the post-Cretaceous cover, where the Mamonia Complex is tectonically imbricated with the Troodos and Akamas ophiolitic suites. Most of these Upper Triassic volcanic rocks have been considered to represent remnants of Triassic oceanic crust and its associated seamounts. New Nd and Pb isotopic data show that the whole Mamonia volcanic suite exhibits features of oceanic island basalts (OIB). Four rock types have been distinguished on the basis of the petrology and chemistry of the rocks. Volcanism began with the eruption of depleted olivine tholeiites (Type 1) and oceanic island tholeiites (Type 2) associated with deep basin siliceous and/or calcareous sediments. The tholeiites were followed by highly phyric alkali basalts (Type 3) interbedded with pelagic Halobia-bearing limestones or white reefal limestones. Strongly LREE-enriched trachytes (Type 4) were emplaced during the final stage of volcanic activity. Nd and Pb isotopic ratios suggest that tholeiites and mildly alkali basalts derived from partial melting of heterogeneous enriched mantle sources. Fractional crystallization alone cannot account for the derivation of trachytes from alkaline basalts. The trachytes could have been derived from the partial melting at depth of mafic material which shares with the alkali basalts similar trace element and isotopic compositions. This is corroborated by the rather similar isotopic compositions of the alkali basalts and trachytes. The correlations observed between incompatible elements (Nb, Th) and [epsilon]Nd and Pb isotopic initial ratios suggest that the Mamonia suite was derived from the mixing of a depleted mantle (DMM) and an enriched component of High [micro] ([micro] = [sup.238]U/[sup.204]Pb, HIMU) type. Models using both Nd and Pb isotopic initial ratios suggest that the depleted tholeiites (Type 1) derived from a DMM source contaminated by an Enriched Mantle Type 2 component (EM2), and that the oceanic tholeiites (Type 2), alkali basalts (Type 3) and trachytes (Type 4) were derived from the mixing of the enriched mantle source of the depleted tholeiites with a HIMU component. None of the Mamonia volcanic rocks show evidence of crustal contamination. The Upper Triassic within-plate volcanism likely erupted in a small southerly Neotethyan basin, located north of the Eratosthenes seamount and likely floored by oceanic crust. Keywords: Late Triassic volcanism, SW Cyprus, Pb-Nd, oceanic island basalts, Neotethys opening.

Author(s): D. Gasperini [1, 2]; J. Blichert-Toft (corresponding author) [1]; D. Bosch [3]; A. Del Moro [4]; P. Macera [2]; P. Télouk [1]; F. Albarède [1] Up to 10 per [...]

Thalamic stimulation appears to be effective in treating people with tremors that are not adequately treated by drugs. Parkinson's disease and multiple sclerosis are two diseases that can cause tremors. Researchers randomly assigned 68 patients with uncontrollable tremor to receive thalamic stimulation or surgical removal of the thalamus. The thalamus is an area of the brain. Thalamic stimulation involves sending an electrical impulse to the area via electrodes implanted in the brain. Ninety-one percent of the patients who received thalamic stimulation benefited from it, compared to 79% of the patients whose thalamus was surgically removed.

The possible role of domain III of the toxic fragment of Bacillus thuringiensis crystal proteins in toxin specificity and in midgut epithelial membrane binding specificity in the diamondback moth was explored using hybrid toxins with domain III substitutions in Cry1C, Cry1E and Cry1Ab. Results showed that domain II and/or domain I, and not domain III, mediates toxin specificity as well as specificity of binding to membrane vesicles in the diamondback moth.