A method for the reconstruction of ground reaction force-time characteristics during gait from force platform recordings of simultaneous foot falls

This paper proposes a method for the reconstruction of foot-ground reaction forces from force platform recordings of two consecutive footfalls. The reconstruction algorithm uses zero-derivative criterion (inflection point) to detect contralateral foot contacts and subtracts contralateral forces from the combined force-time curve in order to reconstruct force-time data. Experimental results suggest that the method can be applied to separate accurately foot-specific gait forces from corrupted force-time data as a result of incorrect stepping on a force platform.     

Concatenated combined modulation and coding of frequency hoppingmultiaccess systems

A spread-spectrum system that does not have a separate state for initial code acquisition is presented. A uniform random variate selects one of several Gold codes for transmission, thus removing the notion of pseudorandom codes from spread-spectrum systems, making the effective code length infinite, and leading to acquisitionless systems. Because coding is critical to the proposed multiaccess frequency-hopping (FH) system, more powerful codes are needed. The performance of the proposed multiaccess system using the combined modulation and coding technique (trellis) concatenated with Reed-Solomon codes in partial-band jamming is investigated. The FH multiaccess performance of noncoherent soft detection of MFSK in association with trellis coding is introduced and the performance compared to that using RS outer/RS inner concatenated codes     

Hypertension optimal treatment (HOT) study: home blood pressure in treated hypertensive subjects

The Hypertension Optimal Treatment Study is a prospective trial conducted in 26 countries. The aims are to (1) evaluate the relationship between three levels of target office diastolic blood pressure (BP) (< or = 80, < or = 85, or < or = 90 mm Hg) and cardiovascular morbidity and mortality in hypertensive patients and (2) examine the effects on cardiovascular morbidity and mortality of 75 mg aspirin daily versus placebo. A total of 19,193 patients between 50 and 80 years of age had been randomized by the end of April 1994. Treatment was initiated with felodipine 5 mg daily, and additional therapy was given in accordance with a set protocol. The present substudy of 926 patients performed in nine countries aimed to (1) compare home with office BP in a representative subsample of the HOT population after the titration of treatment was completed and (2) clarify whether the separation into the target groups could be expanded into the out-of-office setting. The differences between office and home measurements in diastolic BP of 0.2 mm Hg (SD, 9; 95% confidence interval, -0.36 to 0.81; P=.40) and systolic BP of 0.5 mm Hg (SD, 15; 95% confidence interval, -0.53 to 1.46; P=.21) were not significant. The group differences in home BP were 1.9 mm Hg (< or = 80 versus < or = 85) and 1.2 mm Hg (< or = 85 versus < or = 90) for diastolic BP (F=11.69; ANOVA, P<.0001) and 2.6 and 2.1 mm Hg for systolic BP (F=8.44, P=.0002). Thus, office and home BPs measured with the same semiautomatic device are comparable in treated hypertensive subjects in the HOT Study, and the separation into the target groups based on office readings prevails at home.     

Antifungal activity of Indian plant extracts

In vitro studies of water extracts of plants such as Terminalia chebula, Punica granatum, Delonix regia and Emblica officinalis were found to be detrimental to test dermatophytes.     

The effectiveness of biomass hold-up and packing surface in trickling filters

The experimental performance characteristics of a filter bed containing 2 in. Biopac are assessed in terms of the overall rate of BOD removal by biomass films, liquid phase mass transfer and wetted area. The bed was operated with large biomass hold-ups and this determined both the internal geometry of the bed and the liquid flow pattern.Experimentation involving the effect of flow-rate on filter performance suggests that not only was the wetted area dependent on flow-rate in the range investigated and substantially less than the specific surface area of the packing but it was also lower than that associated with very small biomass hold-ups, i.e. thin biomass layers covering the packing pieces without affecting the internal geometry of the bed.The loss of potential performance attributable to the wetted area being less than the specific surface area of the packing depended both on flow-rate and biomass hold-up. At high biomass hold-ups the largest loss of efficiency when compared with the theoretical efficiency of the biomass-substrate-packing system was as much as 55%. The equivalent figure at the same flow-rate, for low biomass hold-ups is 20%. The actual removal efficiencies approach the theoretical efficiencies in the region of the minimum wetting rate.The values obtained for the wetted areas and their dependency on flow-rate support the theory proposed for packed-bed biological film reactors and a methodology for the interpretation of experimental data based upon laboratory scale experimentation for characterization of the BOD-biomass system and pilot-scale experimentation for characterization of the packings.     

Fatty acids in wheat varieties consumed in Bangladesh

Content of ether extractable fat in 6 wheat varieties, consumed in Bangladesh, ranged between 0.9 and 1.9 % of the dry weights. Three saturated and 5 unsaturated fatty acids were detected in these fat extracts by g.l.c. Linoleic acid was major in the fat from Indus-66, Nortino-67 and IP-32, and minor for the other 3 varieties. Stearic acid was major for the fat from Dirk, Mangla-68 and Sonora-64, and minor for the rest. In the former three, the major acids in descending order of abundance were linoleic (41 to 60 %), palmitic (21 to 30 %) and oleic (16 to 26 %). In the later three, this order was oleic (29 to 53 %), palmitic (27 to 41 %) and stearic (13 to 23 %). The unsaturated by saturated fatty acid ratios were above 2 in former group, and below 2 in the later. Palmitic by oleic acid ratios were less than 1 in the former group and about 1 or 2 in the later.     

A priority vector based technique for load forecasting

The priority-vector-based load forecasting technique uses pairwise comparisons to extract relationships from presorted historical hourly load and weather records for up to two years. The presorting is done to identify seasonal boundaries and to categorized the day types. The technique is adaptive in that it internally generates the coefficients of relationships among the governing variables (weather parameters) and the load. As these relationships change over time, such coefficients are automatically updated. The resulting linear method is robust and fairly accurate. This technique was used to forecast the hourly loads for a week, using a 168 h lead time, in different seasons. The only forecast variable used was the dry-bulb temperature. When tested for historical data in the service area of a Virginia electric utility for four weeks in different seasons of the year, the average forecast error remained mostly under 4%. Only 23 individual errors, out of a total of 672 cases, exceeded 6%     

Small toroidal antennas

The radiation fields of small air-cored toroidal antennas carrying a uniform in-phase current have been evaluated. It is shown that according to whether the number of turns is one or more, different radiation patterns result. For the single turn toroid the position of its null axis can be adjusted by altering the ratio of its mean radius to the radius of its cross-section.     

Dry etching and sputtering

Dry etching is an important process for micro- and nanofabrication. Sputtering effects can arise in two contexts within a dry-etch process. Incoming ions cause removal of volatile products that arise from the interaction between the dry-etch plasma and the surface to be etched. Also, the momentum transfer of an incoming ion can cause direct removal of the material to be etched, which is undesirable as it can cause electrical or optical damage to the underlying material. This is largely avoided in dry-etch processes by use of reactive chemistries, although in some processes this component of the etching can be significant. Etch processes, both machine type and possible etch chemistries, are reviewed. Methods of characterizing the electrical and optical damage related to ion impact at the substrate are described. The use of highly reactive chemistries and molecular constituents within the plasma is best for reducing the effects of damage.