Foreign Reserves and Economic Growth: Granger Causality Analysis with Panel Data

This paper will investigate the Granger causality between foreign reserves and economic growth in twenty largest reserves-holding countries ranging from 1980 to 2008. The method of first-differencing each variable is used to estimate the panel data VAR equations for Granger causality test. The results show the foreign reserves unilaterally Granger cause economic growth only in the emerging countries. In the advanced countries, there is no Granger causal relation between foreign reserves and economic growth.

Mean Reversion of Balance of Payments¡GEvidence from Sequential Trend Break Unit Root Tests

We analyze the G7 countries data set of real balance of payments series. The unit root tests with an endogenously determined break date in the trend function proposed by Zivot and Andrews (1992) is employed to characterize the balance of payments series. The empirical results show that allowing for a break in the trend function could alter the outcome of the standard unit root tests for some series.Balance of payments

What Causes the Volatility of the Balancing Item?

This paper analyzes the impacts of timing errors, capital flows and economic openness on the behavior of the balancing item. We choose Norway, Sweden, Philippines and South Africa as sample countries where the size of the balancing item is often excess the IMF's criterion of ‘smallness'. The empirical results show that the sources of the volatility of the balancing item are different among these four countries.Balancing item, Balance of payments

Age Effects on Spatiotemporal Dynamics of Response Inhibition: An MEG Study

Inhibition, the ability to suppress irrelevant information, thoughts or movements, is crucial for humans to perform context-appropriate behaviors. It was suggested that declined cognitive performance in older adults might be attributed to inhibitory deficiencies. Although previous studies have shown an age-associated reduction in inhibitory ability, the understanding regarding its cortical spatiotemporal maps remained limited. Thus, we used a whole-head magnetoencephalography (MEG) to elucidate the age effects on response inhibition, and to explore the brain activation differences in high- and low-performing seniors. We recruited 22 younger and 22 older adults to participate in the visual Go/No-go task. Both behavioral performance and neuromagnetic responses to No-go stimuli were analyzed. The behavioral results showed that the older adults made more false alarm (FA) errors than the younger adults did. The MEG results showed that the seniors exhibited declined cortical activities in middle temporal gyrus (MTG) and delayed activation in MTG, prefrontal cortex (PFC) and pre-supplementary motor area (pre-SMA). Furthermore, among the older adults, more recruitment of the left PFC was found in the high-performers than in the lower-performers. In conclusion, age-related deficiencies in response inhibition were observed in both behavioral performance and neurophysiological measurement. Our results also suggested that frontal recruitment plays a compensatory role in successful inhibition

Wnt proteins regulate acetylcholine receptor clustering in muscle cells

Background: The neuromuscular junction (NMJ) is a cholinergic synapse that rapidly conveys signals from motoneurons to muscle cells and exhibits a high degree of subcellular specialization characteristic of chemical synapses. NMJ formation requires agrin and its coreceptors LRP4 and MuSK. Increasing evidence indicates that Wnt signaling regulates NMJ formation in Drosophila, C. elegans and zebrafish. Results: In the study we systematically studied the effect of all 19 different Wnts in mammals on acetylcholine receptor (AChR) cluster formation. We identified five Wnts (Wnt9a, Wnt9b, Wnt10b, Wnt11, and Wnt16) that are able to stimulate AChR clustering, of which Wnt9a and Wnt11 are expressed abundantly in developing muscles. Using Wnt9a and Wnt11 as example, we demonstrated that Wnt induction of AChR clusters was dose-dependent and non-additive to that of agrin, suggesting that Wnts may act via similar pathways to induce AChR clusters. We provide evidence that Wnt9a and Wnt11 bind directly to the extracellular domain of MuSK, to induce MuSK dimerization and subsequent tyrosine phosphorylation of the kinase. In addition, Wnt-induced AChR clustering requires LRP4. Conclusions: These results identify Wnts as new players in AChR cluster formation, which act in a manner that requires both MuSK and LRP4, revealing a novel function of LRP4.NeurosciencesSCI(E)24ARTICLEnull

Structural design of a silicon six-wafer micro-combustor under the effect of heat transfer boundary condition at the outer walls

The aim of this investigation was to establish a methodology for designing highly stressed micro fabricated structures by studying the structural design issues associated with a silicon six–wafer micro combustor under the effect of heat transfer boundary condition at the outer walls. Some experimental and numerical simulation results have indicated that the flame can not be sustained in the micro combustor if the poor heat transfer coefficients at the outer wall are present. This could cause the combustor wall temperature higher than the auto ignition temperature of reactants and results in the upstream burning. Since silicon has relatively poor high temperature strength and creep resistance when the temperature is above the brittle to ductile transition temperature (BDTT), e.g. 900K, the combustion in the recirculation jacket could possibly damage the micro combustor due to the high wall temperature

Numerical investigation of the structure of a silicon six-wafer micro-combustor under the effect of hydrogen/air ratio

Research reports indicate that sufficiently high equivalence ratio of the hydrogen/air mixture leads to the upstream burning in the recirculation jacket, possibly damaging the micro- combustor due to the high wall temperature. This work investigates the influences of the equivalence ratio of the mixture on the structure of a micro-combustor device. Numerical simulation approaches focused on the structural design of the micro-combustor with the flame burning in the recirculation jacket. Combustion characteristics of the combustor were first analysed based on 2D computational Fluid Dynamics (CFD), and then thermo-mechanical analysis on the combustor was carried out by means of 3D Finite Element Analysis (FEA) method. The results showed that the most dangerous locations where the critical failure could possibly occur lay at the burning areas in the recirculation jacket due to the poor bonding, the high temperature and the residual stress. The results of this study can be used for the design and improvement of the micro-combustors

The effect of adding a home program to weekly institutional-based therapy for children with undefined developmental delay: A pilot randomized clinical trial

AbstractBackgroundEarly rehabilitation for children with developmental delay without a defined etiology have included home and clinic programs, but no comparisons have been made and efficacy is uncertain. We compared a weekly visit for institutional-based therapy (IT) to IT plus a structured home activity program (HAP).MethodsSeventy children who were diagnosed with motor or global developmental delay (ages 6-48 months and mean developmental age 12.5 months) without defined etiology were recruited (including 45 males and 23 females). The outcomes included the comprehensive developmental inventory for infants and toddlers test and the pediatric evaluation of disability inventory.ResultsChildren who received only IT improved in developmental level by 2.11 months compared with 3.11 months for those who received a combination of IT and HAP (p = 0.000). On all domains of the comprehensive developmental inventory for infants and toddlers test, except for self-help, children who participated in HAP showed greater improvements, including in cognition (p = 0.015), language (p = 0.010), motor (p = 0.000), and social (p = 0.038) domains. Except on the subdomain of self-care with caregiver assistance, the HAP group showed greater improvement in all the pediatric evaluation of disability inventory subdomains (p < 0.05).ConclusionEarly intervention programs are helpful for these children, and the addition of structured home activity programs may augment the effects on developmental progression