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Dominant Power (dominant + power)
Selected Abstracts22 Comparison of multichannel electrogastrograms obtained with the use of three different electrode typesNEUROGASTROENTEROLOGY & MOTILITY, Issue 6 2006K JONDERKO Background/Aims:, Multichannel recording of the gastric myoelectrical activity (GMA) is a promising evolution of electrogastrography. In the study we searched for electrodes the most suitable to obtain high quality multi-channel electrogastrograms. Methods:, Twelve young volunteers (9 F, 3 M, aged 24.3 ± 0.6 years) underwent on separate days three four-channel electrogastrographic recordings of the GMA: 30 min fasted and 90 min after a solid meal stimulation. The electrogastrograms were recorded in randomized order with 3M Red Dot class Ag/AgCl electrodes designed primarily for long-term electrocardiographic monitoring: type2222 (conductive area, CA/total area, TA): 2.00/10.24 cm2, type2271 2.54/29.64 cm2, type2660 11.64/11.64 cm2 (total surface conductive!) and subsequently analysed with Polygram NetÔ EGG 311224 software (Medtronic, USA). Electrical resistance between active electrodes relative to the reference one was measured with a digital ohmmeter before and after the recording session. Results:, Type2660 yielded consistently higher electrical resistance than the other electrode types, moreover in the case of type2271 and type2660 electrical conductivity significantly improved at the end of the recording relative to the basal measurement. Analysis of variance involving the relative time-share of normogastria, meal-induced change in dominant power, as well as a set of parameters unique for the multichannel electrogastrography and intended to characterize the so-called spatial displacement of the gastric slow waves did not reveal any statistically significant effect of the electrode type on the parameters of the multichannel electrogastrogram. Although, when particular numerical data were inspected, type2271 was found to perform slightly worse than the other electrode types. Type2271 was also rated the less handy among the electrodes tested. Conclusion:, Multichannel surface electrogastrography seems to be technically feasible with any type of high quality Ag/AgCl electrodes available on the market, whereas small dimensions enabling easy placement on the abdomen may be a feature favouring the choice of a particular electrode type for this examination. [source] 34 Senso-reflexory control of the gastric myoelectrical activity , effect of oral exposure to a sweet or a bitter taste on a multichannel electrogastrogramNEUROGASTROENTEROLOGY & MOTILITY, Issue 6 2006M DZIELICKI Aim:, To examine the effect of sensory stimulation with a sweet or a bitter taste on the interdigestive gastric myoelectrical activity (GMA) in humans. Methods:, Eighteen healthy subjects (10F, 8M) underwent on two separate days four-channel electrogastrographic recordings comprising three consecutive 35 min periods: (i) basal fasted, (ii) a stimulation epoch while a subject was chewing an agar cube soaked with a taste-delivering substance (saccharose for the sweet taste, quinine hydrochloride for the bitter taste), (iii) a post-stimulatory (recovery) epoch. An electrocardiogram was simultaneously registered for the purpose of the heart rate variability (HRV) analysis. Results:, Exposure to the sweet taste brought about an increase in the power of the high frequency (HF: 0.15,0.4 Hz) band of the power spectrum-analyzed HRV data. The bitter taste had no effect on the HRV. During the stimulation and the recovery epoch a statistically significant augmentation in the relative time share of tachy- and bradygastria within the multichannel electrogastrogram was found either with the sweet or the bitter taste. Whereas no any other modifications of the GMA were elicited by the sweet taste, the exposure to the bitter taste resulted in a statistically significant decrease in the relative time share of normogastria, a decline in the dominant frequency and the dominant power of the gastric slow waves, as well as a reduction in the percentage of the slow wave coupling. Conclusions:, (i) Exposure to the sweet taste elicits a vagal arousal expressed by an increase in the HF power, whereas the bitter taste does not affect the equilibrium between the parasympathetic and the sympathetic component of the autonomous nervous system; (ii) The increased relative time contribution of tachy- and bradygastria within the electrogastrogram during both the stimulation and the recovery epoch should be considered an unspecific phenomenon because it accompanied stimulation either with the sweet or the bitter taste; (iii) The inhibitory effect of the bitter taste on the GMA, reflected by a diminution in the dominant frequency and the dominant power of the gastric slow waves, as well as their reduced coupling, may be indicative of an evolutionary archetype of a warning reaction of the human (mammalian) organism towards this taste. [source] 35 Electrogastrography in healthy participants: comparison of children and adultsNEUROGASTROENTEROLOGY & MOTILITY, Issue 6 2006CA FRIESEN The current study examined whether electrogastrogram (EGG) patterns differ between children/adolescents and adults, including whether EGG recordings obtained from healthy children would be considered normal by standards established for adults. Twenty-eight healthy children (54% females; ages 8,17, M = 12.4 years) were evaluated and compared to 15 healthy adults. EGGs were recorded for 30 min in the fasting state and for 1 h following a standard meal. For both pediatric and adult participants, there was a significant increase in both the dominant frequency and the dominant power from the pre- to the post , prandial period (p < 0.001 for each). There was a significant post-prandial increase in the %normal slow waves in pediatric participants only (81.5 vs. 89.0% vs. p < 0.001). Children demonstrated a significantly lower mean fasting %normal slow waves (81.5% vs. 94.2%) and a significantly greater fasting % tachygastria (8.9% vs. 2.3%) than did adults. Other parameters did not differ. Using adult standards, the %normal slow waves were ,70% of recording time in 96% children in the fasting state and in 100% in the postprandial period. A postprandial power increase was seen in 89% of the children. In conclusion, while adults should not be used as controls in pediatric studies of EGG, our data would indicate that American Motility Society (AMS) consensus adult criteria for a normal EGG are appropriate to apply to children and adolescents when utilizing methodology and meal challenge similar to that used to establish the adult norms. [source] Facing a Post-American WorldNEW PERSPECTIVES QUARTERLY, Issue 3 2008FAREED ZAKARIA American-led globalization has enabled the third great powershift of the last five hundred years,the "rise of the rest" following on the rise of the West and then the rise of the US as the dominant power in the West. When China, India, Brazil, Turkey and the rest sit at the table of global power with the West what will the world order look like? Will it be post-American? Will it be culturally non-Western, but play by the same rules of an open international order laid down by the American's after World War II? In the following pages, leading American and Asian intellectuals ponder these questions. [source] Here Comes the Second WorldNEW PERSPECTIVES QUARTERLY, Issue 3 2008PARAG KHANNA American-led globalization has enabled the third great powershift of the last five hundred years,the "rise of the rest" following on the rise of the West and then the rise of the US as the dominant power in the West. When China, India, Brazil, Turkey and the rest sit at the table of global power with the West what will the world order look like? Will it be post-American? Will it be culturally non-Western, but play by the same rules of an open international order laid down by the American's after World War II? In the following pages, leading American and Asian intellectuals ponder these questions. [source] The Politics of PopulationINTERNATIONAL STUDIES REVIEW, Issue 4 2006TADEUSZ KUGLER This essay evaluates the implications of international political development on demographic transitions and economic outcomes from 1980 to 2050. Countries with high levels of political capacity experience the sharpest declines in birth and death rates as well as the greatest gains in income. Politics indirectly and directly affects the environment within which individuals make decisions about the size of families; these decisions, in turn, change the future economic dynamics of a country. We find that political capacity ensures that rules are evenly applied, allowing investment for long-term gain. Our projections show that under conditions of high political capacity, anticipated demographic and economic transformations will allow China to supersede the dominance of the United States by the end of this century and will also enable the rise of India into the ranks of the dominant powers. We assess the consequences of these changes in world politics. [source] | ||||||||||