Black currant seed oil feeding and fatty acids in liver lipid classes of guinea pigs

Guinea pigs were fed one of three diets containing 10% black currant seed oil (a source of gamma-linolenic (18∶3 n−6) and stearidonic (18∶4 n−3) acids), walnut oil or lard for 40 days. The fatty acid composition of liver triglycerides, free fatty acids, cholesteryl esters, phosphatidylinositol, phosphatidylserine, cardiolipin, phosphatidylcholine and phosphatidylethanolamine were determined. Dietary n−3 fatty acids found esterified in liver lipids had been desaturated and elongated to longer chain analogues, notably docosapentaenoic acid (22∶5 n−3) and docosahexaenoic acid (22∶6 n−3). When the diet contained low amounts of n−6 fatty acids, proportionately more of the n−3 fatty acids were transformed. Significantly more eicosapentaenoic acid (EPA) (20∶5 n−3) was incorporated into triglycerides, cholesteryl esters, phosphatidylcholine and phosphatidylethanolamine of the black currant seed oil group compared with the walnut oil group. Feeding black currant seed oil resulted in significant increases of dihomogamma-linolenic acid (20∶3 n−6) in all liver lipid classes examined, whereas the levels of arachidonic acid (20∶4 n−6) remained relatively stable. The ratio dihomo-gamma-linolenic acid/arachidonic acid was significantly (2.5-fold in PI to 17-fold in cholesteryl esters) higher in all lipid classes from the black currant seed oil fed group.     

The design of biplanar,shielded, minimum energy,or minimum power pulsed B0 coils

By extending the formalism previously developed for the design of unshielded, biplanar gradient coils, shielded biplanarB ₀ coils optimized for homogeneity and either minimum energy or minimum power may be designed. We present results from an integrated approach to shielded biplanar coil design, the results of which are also applicable to gradient coils, enabling the design of shielded coils with a concomitant decrease in total inductance of the coil. Length constraints are also included in the integrated minimization procedure. Results from a preliminary design indicate that high-homogeneity, low-impedance, well-shielded coils result from this design approach.     

Chemorheology of an epoxy resin for pultrusion

The Williams-Landel-Ferry (W-L-F) equation was shown to describe the temperature dependence of the viscosity of a sulfonium accelerated, amine cured epoxy resin that had been formulated for pultrusion. The reference temperature and the viscosity at the reference temperature of the W-L-F equation were found to be simple functions of the resin advancement as determined by isothermal differential scanning calorimetry, A method is described of constructing the baseline for temperature-programmed differential scanning calorimetry analyses in which the heat capacity is changing due to reaction.     

Improving the Error Rate Performance of Turbo Codes using the Forced Symbol Method

This letter presents a method that significantly improves the error rate performance of turbo codes, especially in the error flare region, without changing the basic encoder structure. This method applies repeated decoding, with one or more symbols being forced to certain values, when an error is detected. This forces the decoder to output alternate sets of decisions that can then be checked for errors. The effectiveness of this method is demonstrated by its ability to lower the error flare by several orders of magnitude as soon as the error flare region is encountered. For the DVB-RCS 8-state, rate 1/2, double-binary turbo code and packets of 1504 information bits (MPEG-size), this method yields performance about 0.4 dB from the sphere-packing bound down to a packet error rate of 10-7.     

An inverse methodology for high-frequency RF coil design for MRI with de-emphasized B1 fields.

An inverse methodology for the design of biologically loaded radio-frequency (RF) coils for magnetic resonance imaging applications is described. Free space time-harmonic electromagnetic Green's functions and de-emphasized B1 target fields are used to calculate the current density on the coil cylinder. In theory, with the B1 field de-emphasized in the middle of the RF transverse plane, the calculated current distribution can generate an internal magnetic field that can reduce the central overemphasis effect caused by field/tissue interactions at high frequencies. The current distribution of a head coil operating at 4 T (170 MHz) is calculated using an inverse methodology with de-emphasized B1 target fields. An in-house finite-difference time-domain routine is employed to evaluate B1 field and signal intensity inside a homogenous cylindrical phantom and then a complete human head model. A comparison with a conventional RF birdcage coil is carried out and demonstrates that this method can help in decreasing the normal bright region caused by field/tissue interactions in head images at 170 MHz and higher field strengths.     

A power quality and reliability index based on customerinterruption costs

Standard reliability indexes such as SAIDI ignore the variation in interruption costs with customer type. Thus, expenditure decisions driven by these indices that impact reliability, will not lead to the optimum improvement in value of service to customers. An index equal to customer interruption costs divided by energy sales (CICs/kWh) overcomes this deficiency. It is equally useful for identifying best-business-value solutions to power quality problems. It enables a supplier to decide which portfolio of projects (affecting power quality, or reliability, or neither) earns the highest return on investment, and allows a direct comparison of its value-creation record with that of its competitors