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111.
Diedrichsen J?rn; Ivry Richard B.; Hazeltine Eliot; Kennerley Steven; Cohen Asher 《Canadian Metallurgical Quarterly》2003,29(1):64
Four experiments were conducted to identify the locus of interference observed during the preparation of bimanual reaching movements. Target locations were specified by color, and the right-hand and left-hand targets could be either the same or a different color. Movements of different amplitudes (Experiment 1) or different directions (Experiment 2) to targets of the same color were initiated more quickly than symmetric movements to targets of different colors. These results indicate that costs observed during bimanual movements arise during target selection rather than during motor programming. Experiments 3 and 4 further examined the interference associated with target selection. Reaction time costs were found with unimanual movements when the target was presented among distractors associated with responses for the other hand. Interference observed during bimanual reaching appears to reflect difficulty in segregating the response rules assigned to each hand. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
112.
Schlak M. Weinert C.M. Albrecht P. Nolting H.-P. 《Photonics Technology Letters, IEEE》1991,3(1):15-16
The use of a two-dimensional finite difference simulation technique to determine optimal design parameters for the fabrication of TE/TM-mode converters on (001) InP substrate is discussed. Based on design rules extracted from the calculations, a tunable device for an operating wavelength of 1.56 μm has been fabricated and polarization conversion of 45°, suitable for operation in a polarization diversity network has been achieved at an effective voltage of 32 V 相似文献
113.
Under oxygen-rich conditions in H2 + NO + O2 mixtures, Pd/V2O5/Al2O3 catalysts are active and highly selective (~80%) for NOx reduction to N2. In situ DRIFT spectroscopy and reactor data show that the system operates via formation of NHx species on the highly dispersed V2O5 component. Both NH3 and NH4 + are formed, with the latter dominant. The role of the palladium component is also discussed. 相似文献
114.
115.
Richard D. Prosser 《Energy Economics》1985,7(1):9-12
Four models with different lag structures are used to express final energy demand in OECD from 1960–1982 as a function of real GDP and average energy price. The income and long-run price elasticities are not significantly dependent on the model specification, but the Koyck lag scheme, estimated in its distributed lag form, is found to give the most satisfactory results. The statistical properties of the data together with evidence of trends in the elasticities both suggest that the period of falling real prices prior to 1971 is not comparable to the present period. For the period after 1971, an income elsticity of 1.02 and a long-run price elasticity of -0.37 are obtained. 相似文献
116.
117.
We recently reported the presence of reliable asymmetries in frontal-brain electrical activity in infants that distinguished between certain positive- and negative-affect elicitors. In order to explore the degree to which these asymmetries in brain activity are associated with individual differences in affective response, 35 ten-month-old female infants were presented with a stranger-approach, mother-approach, and maternal-separation experience while an electroencephalogram (EEG) from the left- and right-frontal and left- and right-parietal scalp regions was recorded and facial and other behavioral responses were videotaped. Changes in frontal-EEG asymmetry reflected behavioral changes between conditions. In addition, individual differences in affective response to separation were related to differences in frontal-brain asymmetries. These findings indicate that lawful changes exist in asymmetries of frontal-brain activation during the expression of certain emotions in the first year of life and that individual differences in emotional responsivity are related to these measures of brain activity. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
118.
Johann Lepschy-v. Gleissenthal Richard Dietrich Erwin Märtlbauer Manfred Schuster Adalbert Süß Gerhard Terplan 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1989,188(6):521-526
Summary Bavarian cereals and wheat flour from the 1987 harvest were analysed for nivalenol (NIV) and deoxynivalenol (DON) using high performance liquid chromatography (HPLC) and for T-2 toxin and zearalenone (ZEA) by enzyme-linked-immunosorbent as say (ELISA). The study included 190 field samples of wheat, barley, rye and oat with visibly damaged ears, 45 samples of wheat intended for feed production and two series of wheat flour (type 550) and whole wheat flour collected in October 1987 and June 1988. The field samples examined showed a high DON contamination of wheat (87%) with an average of 3.96 mg/kg and a maximum of 43.8 mg/kg. Mean levels between 0.33 mg/kg and 0.27 mg/kg DON could be detected in barley, rye and oat. Of the wheat samples, 58% contained ZEA with a maximum of 1.560 mg/kg. The highest levels of ZEA were detected in samples which also showed high concentrations of DON. The NIV and T-2 toxin levels were comparatively low. Thirty percent of the samples showed NIV concentrations between 0.04 mg/kg and 0.29 mg/kg and 38% contained between 0.005 and 0.60 mg/kg of T-2. In the wheat samples for feed production, only DON was detected with an average of 0.190 mg/kg and a maximum of 0.75 mg/kg. The highest DON levels (0.58 mg/kg) from October 1987 were found in the wheat flour samples which were lower than the highest DON concentration (3.24 mg/kg) detected in the samples collected during June 1988. This fact was probably due to a substantial amount of non-contaminated wheat from 1986. The toxin concentrations in the whole wheat flour were not higher than in the type 550 flour. The regional distribution of the mean DON concentrations showed the highest levels in Middle and Lower-Franconia.
Vorkommen von Fusarium Mykotoxinen in bayerischem Getreide der Ernte 1987
Zusammenfassung Cerealien und Weizenmehle der bayerischen Ernte 1987 wurden mittels hochauflösender Flüssigchromatographie (HPLC) auf Nivalenol (NIV) und Deoxynivalenol (DON) Bowie mit Enzymimmunoassay auf T-2 Toxin und Zearalenon (ZEA) analysiert. Die Untersuchungen umfaßten 190 Feldproben von Weizen, Gerste, Roggen und Hafer, die alle optisch erkennbaren Fusarienbefall aufwiesen, 45 Futterweizenproben Bowie zwei Probenserien von Weizenmehlen der Type 550 und Vollkornweizenmehlen, die im October 1987 und im Juni 1988 gezogenwurden. — Die Untersuchungen der Feldproben ergaben eine hohe DON-Kontamination des Weizens (87%) mit einem durchschnittlichen Gehalt von 3,96 mg/kg und einem Maximalgehalt von 43,8 mg/kg. In Gerste, Roggen und Hafer konnten durchschnittlich zwischen 0,33 mg/kg und 0,27 mg/kg DON-nachgewiesen werden. 58% der Winterweizenproben wiesen Zearalenon mit einem Maximalgehalt von 1,56 mg/kg auf. Die höchsten ZEA-Werte wurden in Proben ermittelt, die gleichzeitig einen hohen DON-Gehalt aufwiesen. Die Konzentrationen von NIV und T-2 Toxin waren vergleichsweise niedrig. 30% der Proben hatten NIV-Gehalte zwischen 0,04 mg/kg und 0,29 mg/kg und 38% enthielten T-2 Toxin zwischen 0,005 mg/kg und 0,06 mg/kg. In den Futterweizenproben konnte DON als einziges Toxin mit einem Gehalt von durchschnittlich 0,19 mg/kg und maximal 0,75 mg/kg festgestellt werden. Die Weizenmehle, die im October 1987 gezogen wurden, wiesen maximal 0,58 mg/kg DON auf. Die Gehalte lagen damit medriger als die der Mehlproben vom Juni 1988, die maximal 3,24 mg/kg und durchschnittlich 0,26 mg/kg DON enthielten. Dieser Sachverhalt könnte auf Anteile von nicht kontaminiertem Weizen der Ernte 86 an den im October gezogenen Mehlproben zurückgeführt werden. Die Toxingehalte der Vollkornmehle waren nicht höher als die der Weizenmehle der Type 550. Die höchsten Durchschnittsgehalte von DON wurden in Mittel- und Unterfranken festgestellt.相似文献
119.
The behavioral response (e.g. changes in indoor temperatures, attention to window and door openings) to residential technical efficiency improvements (e.g. attic insulation, storm windows) is an important and largely unresolved issue. Although there is considerable discussion concerning the extent to which households take back some of the energy savings due to technical efficiency improvements in increased comfort, there is almost no empirical evidence on the subject.Detailed electricity billing data (from mid-1981 to mid-1983) were analyzed for 79 households that received financial assistance from the Bonneville Power Administration to retrofit their homes in mid-1982. The mean retrofit expenditure in these homes was $1900; the mean reduction in annual electricity use was 4700 kWh, of which 83% was due to reductions in space heating electricity use. Analysis of the electricity billing data suggests that these households increased their indoor temperature settings after retrofit by almost 1 °F on average. This temperature increase led to an estimated average loss of almost 600 kWh of electricity saving. In other words, roughly 10% of the energy saving due to retrofit was taken back in terms of increased comfort. These results concerning changes in indoor temperatures should be viewed cautiously because of limitations in the analytical method and the large variation across households. 相似文献
120.
R. James Maguire Richard J. Tkacz David L. Sartor 《Journal of Great Lakes research》1985,11(3):320-327
Water and sediment samples from 29 locations in the Detroit and St. Clair rivers were analyzed for the highly toxic tri-n-butyltin (Bu3Sn+) species and for the less toxic di-n-butyltin (Bu2Sn2+) and n-butyltin (BuSn3+) species and inorganic tin. In general, locations sampled in the St. Clair River were less contaminated with butyltin species than those in the Detroit River. Inorganic tin and BuSn3+ were detected in over 90% of all subsurface water samples, while Bu2Sn2+ and Bu3Sn+ were detected in 45 and 28% of the same samples, respectively. The highest concentration ofBu3Sn+ in subsurface water, 5.9 × 10?10 mol Sn/L, was at the mouth of the Ecorse River, a tributary of the Detroit River. The three butyltin species and inorganic tin were also detected in 23–46% of all sediment samples. The highest concentrations of Bu3Sn+ in sediment were found close to the mouths of the River Rouge, another tributary of the Detroit River, and the Ecorse River, and were 6.2 × I0–7 and 1.7 × I0–7 mol Sn/kg dry weight, respectively, for the top 2 cm of sediment. 相似文献