International Demonstration Effect and Domestic Division of Labour: A Simple Model

The implications of the international demonstration effect (IDE) for the development of underdeveloped economies have long been studied and debated. Yet few formal analyses exist in the literature, especially regarding its implications for the growth of domestic markets and the division of labour in developing economies. We offer an analysis of endogenous specialization under IDE, the first of its kind, showing that, far more complicated than the scenario held by conventional wisdom, IDE makes more difficult the emergence of the market underpinning the domestic division of labour, but facilitates the expansion of the market once the market has been developed.External habit formation; specialization and division of labour; international demonstration effect; economic development; emergence and extent of the market.

Patterns and influencing factor of synonymous codon usage in porcine circovirus

<p>Abstract</p> <p>Background</p> <p>Analysis of codon usage can reveal much about the molecular evolution of the viruses. Nevertheless, little information about synonymous codon usage pattern of porcine circovirus (PCV) genome in the process of its evolution is available. In this study, to give a new understanding on the evolutionary characteristics of PCV and the effects of natural selection from its host on the codon usage pattern of the virus, Patterns and the key determinants of codon usage in PCV were examined.</p> <p>Methods</p> <p>We carried out comprehensive analysis on codon usage pattern in the PCV genome, by calculating relative synonymous codon usage (RSCU), effective number of codons (ENC), dinucleotides and nucleic acid content of the PCV genome.</p> <p>Results</p> <p>PCV genomes have relatively much lower content of GC and codon preference, this result shows that nucleotide constraints have a major impact on its synonymous codon usage. The results of the correspondence analysis indicate codon usage patterns of PCV of various genotypes, various subgenotypes changed greatly, and significant differences in codon usage patterns of Each virus of Circoviridae.There is much comparability between PCV and its host in their synonymous codon usage, suggesting that the natural selection pressure from the host factor also affect the codon usage patterns of PCV. In particular, PCV genotype II is in synonymous codon usage more similar to pig than to PCV genotype I, which may be one of the most important molecular mechanisms of PCV genotype II to cause disease. The calculations results of the relative abundance of dinucleotides indicate that the composition of dinucleotides also plays a key role in the variation found in synonymous codon usage in PCV. Furthermore, geographic factors, the general average hydrophobicity and the aromaticity may be related to the formation of codon usage patterns of PCV.</p> <p>Conclusion</p> <p>The results of these studies suggest that synonymous codon usage pattern of PCV genome are the result of interaction between mutation pressure and natural selection from its host. The information from this study may not only have theoretical value in understanding the characteristics of synonymous codon usage in PCV genomes, but also have significant value for the molecular evolution of PCV.</p

Dimethyl 3,3′-diphenyl-2,2′-[(S)-thio­phene-2,5-diylbis(carbonyl­aza­nedi­yl)]dipropano­ate

The asymmetric unit of the title compound, C26H26N2O6S, contains two independent mol­ecules; each has twofold symmetry with the S atom and the mid-point of the C—C bond of the thio­phene ring located on a twofold rotation axis. In the two mol­ecules, the terminal benzene rings are oriented at dihedral angles of 65.8 (3) and 63.5 (3)° with respect to the central thio­phene rings. The meth­oxy­carbonyl group of one mol­ecule is disordered over two positions with site-occupancy factors of 0.277 (12) and 0.723 (12). Inter­molecular N—H⋯O hydrogen bonding is present in the crystal structure

A Capacitive Humidity Sensor Based on Multi-Wall Carbon Nanotubes (MWCNTs)

A new type of capacitive humidity sensor is introduced in this paper. The sensor consists of two plate electrodes coated with MWCNT films and four pieces of isolating medium at the four corners of the sensor. According to capillary condensation, the capacitance signal of the sensor is sensitive to relative humidity (RH), which could be transformed to voltage signal by a capacitance to voltage converter circuit. The sensor is tested using different saturated saline solutions at the ambient temperature of 25 °C, which yielded approximately 11% to 97% RH, respectively. The function of the MWCNT films, the effect of electrode distance, the temperature character and the repeatability of the sensor are discussed in this paper

The strong decay patterns of ZcZ_c and ZbZ_b states in the relativized quark model

Employing the relativized quark model and the quark-interchange model, we investigate the decay of the charged heavy quarkonium-like states $Z_c(3900)$, $Z_c(4020)$, $Z_c(4430)$, $Z_b(10610)$ and $Z_b(10650)$ into the ground and radially excited heavy quarkonia via emitting a pion meson. The $Z_c$ and $Z_b$ states are assumed to be hadronic molecules composed of open-flavor heavy mesons. The calculated decay ratios can be compared with the experimental data, which are useful in judging whether the molecule state assignment for the corresponding $Z_c$ or $Z_b$ state is reasonable or not. The theoretical framework constructed in this work will be helpful in revealing the underlying structures of some exotic hadrons.Comment: 19 pages, 4 figures, version published in EPJ