ECONOMIC INTEGRATION AND ENDOGENOUS GROWTH: AN EXPLANATION USING AK MODEL

Abstract: This research investigates the impacts of economic integration on endogenous growth by an application of the AK learning-by-doing model. Assuming that the knowledge that increases the productivity of labor will be created by accumulated capital, we divide economic integration into two different categories: one-way and two-way integration. The results show that two identical countries cannot have any benefits from economic integration. If two countries are different, the domestic country should only integrate with foreign countries that have a lower cost of capital of wage, or higher learning coefficient (the speed of transferring accumulated capital to knowledge) in the case of one-way integration. The same conclusion is still drawn in the case of two-way integration for two similar countries.Keywords: economic integration, endogenous growth, AK mode

FLIGHT-TO-QUALITY OR CONTAGION DURING U.S. SUBPRIME CRISIS: EVIDENCE FROM VIETNAM’S FINANCIAL MARKETS

Abstract: This study investigates whether contagion or flight-to-quality occurred in Vietnam’s financial markets during the US subprime crisis in 2007. We apply the asymmetric dynamic conditional correlation model (ADCC-GARCH (1,1)) to daily stock-index and bond index returns of Vietnam’s and US stock markets. We test for contagion or flight-to-quality by using a test for difference in dynamic conditional correlation means. The results show a contagion between the US and Vietnam’s stock markets, confirming the widespread influence of the US stock market on a young market like Vietnam. This result suggests a low benefit from diversification for investors holding portfolios containing assets in Vietnam’s stock market and US stock market during the crisis. Moreover, the relationship between Vietnam’s stock and bond markets represents a flight-to-quality during the US subprime crisis. This finding shows that the investors tend to hold less risky assets, i.e., bonds, instead of stocks during this turbulent period in Vietnam.Keywords: international financial contagion, flight-to-quality, Vietnam, US subprime crisis, ADCC-GARC

NOISE TRADER RISK: EVIDENCE FROM VIETNAM STOCK MARKET

Abstract: This paper investigates the existence of noise trader risk in Vietnam’s stock market and its effect on the daily returns of stock prices. The methodologies contain the estimation of GARCH (1,1) model to filter the residuals using the moving average method to calculate the impact of information traders. Noise trader risk or the risk that is caused by noise traders is derived by subtracting the residuals by the rational traders’ impact. We find that the noise trader risk does exist in Vietnam’s stock market and its impact on daily returns of stocks is unpredictable. Meanwhile, we find a positive impact of information traders on the stock returns. It increases the daily stock returns, and in turn, helps the market to correct itself because the stock prices move back to its fundamental value.Keywords: noise trader risk, GARCH (1,1), Vietnam’s stock marke

Willingness to adopt improved shrimp aquaculture practices in Vietnam

The shrimp industry plays a leading role in aquaculture development in Vietnam. Currently, the government is running a credit subsidy program to support farmers investing in improved production methods. This paper aimed to investigate white-legged shrimp farmers’ willingness to invest in improved production methods and to examine whether the current government policy for the sector is in line with farmers’ preferences using a discrete choice experiment. The results show that farmers do not care about the environmental impacts but emphasize increased yields and more successful crops as the main drivers of their willingness to invest. There is a mismatch between the current subsidized interest rate and farmers’ required interest rate. These findings suggest that to promote better investment in improved production methods, the government should focus on the regulatory framework, monitoring and control of environmental impacts, and reevaluate the size of the credit subsidy.acceptedVersio

Effects of guava (Psidium guajava L.) and bhumi amla (Phyllanthus amarus Chum et Thonn) extracts on haematological parameters and oxidative stress of striped catfish (Pangasianodon hypophthalmus) fingerlings exposed to high-temperature stress

Effects of guava (Psidium guajava L.) and bhumi amla (Phyllanthus amarus Chum et Thonn) on haematology and thermal stress mitigation of striped catfish (Pangasianodon hypophthalmus) were investigated. In a 42-day trial, fish were administered 4 diets as control (without extract), 0.2% P. guajava (Pg0.2), 0.5% P. amarus (Pa0.5), and a mixture of Pg0.2 and Pa0.5 (Mix). Fish were then subjected to temperatures of 27°C, 31°C, and 35°C for another 42 days. Haematological parameters were highest at 35°C, but these parameters were not significantly different from values recorded at 31°C on day 14 post-temperature challenge. The Pg0.2 diet modified red blood cells, haematocrit, and haemoglobin (p<0.05). The lowest glucose concentration was recorded in Pg0.2 (57.4±1.34 mg/100 mL) and Mix (58.9±1.87 mg/100 mL) groups after 14 days of thermal exposure. Glucose concentration surged on the third-day post-temperature challenge, then declined, and was maintained at 35°C until the end of the experiment which was not significant if compared to those at 27°C. Pg0.2 and Mix diets significantly reduced lipid peroxidation and enhanced catalase in gill and liver after 42 days. In the case average water temperature in the Mekong Delta remains below 35°C, the feeding diets for P. hypophthalmus administered Pg0.2 or..

Cider Production from King Mandarin (Citrus nobilis Lour.) and Its Antioxidant Activity

With the necessity of diversifying alcoholic beverages, cider has become a kind of drink that can fulfill this demand. This is because the cider will be diversified depending on the kinds of fruit that are chosen to be used for the cider fermentation. Therefore, this study aims to investigate the effects of dilution ratio, Brix, pH, and yeast concentration on the production of cider from king mandarin (Citrus nobilis Lour.), and to evaluate the analytical characteristics and antioxidant activity of the product. After the investigation, it can be claimed that the dilution of the juice causes the ethanol content to decrease, whereas the increase of Brix, pH, and yeast concentration makes the ethanol content increase. However, the proportional increase in the ethanol content with Brix, pH, and yeast concentration has its limitations. Specifically, when the Brix and the yeast concentrations were, respectively, higher than 16°Brix and 0.04%, the ethanol content tended to maintain the same. This is also the same when the pH was lower than 4.5. In addition, by using the DPPH and ABTS●+ methods, the antioxidant activity of cider is estimated to be lower than the one of the juice before fermentation, which is smaller than 3.78 times for the DPPH method and 3.76 times for the ABTS●+ method

Simultaneously induced mutations in eIF4E genes by CRISPR/Cas9 enhance PVY resistance in tobacco

Tobacco is an important commercial crop and a rich source of alkaloids for pharmaceutical and agricultural applications. However, its yield can be reduced by up to 70% due to virus infections, especially by a potyvirus Potato virus Y (PVY). The replication of PVY relies on host factors, and eukaryotic translation initiation factor 4Es (eIF4Es) have already been identified as recessive resistance genes against potyviruses in many plant species. To investigate the molecular basis of PVY resistance in the widely cultivated allotetraploid tobacco variety K326, we developed a dual guide RNA CRISPR/Cas9 system for combinatorial gene editing of two clades, eIF4E1 (eIF4E1-S and eIF4E1-T) and eIF4E2 (eIF4E2-S and eIF4E2-T) in the eIF4E gene family comprising six members in tobacco. We screened for CRISPR/Cas9-induced mutations by heteroduplex analysis and Sanger sequencing, and monitored PVY(O) accumulation in virus challenged regenerated plants by DAS-ELISA both in T0 and T1 generations. We found that all T0 lines carrying targeted mutations in the eIF4E1-S gene displayed enhanced resistance to PVY(O) confirming previous reports. More importantly, our combinatorial approach revealed that eIF4E1-S is necessary but not sufficient for complete PVY resistance. Only the quadruple mutants harboring loss-of-function mutations in eIF4E1-S, eIF4E1-T, eIF4E2-S and eIF4E2-T showed heritable high-level resistance to PVY(O) in tobacco. Our work highlights the importance of understanding host factor redundancy in virus replication and provides a roadmap to generate virus resistance by combinatorial CRISPR/Cas9-mediated editing in non-model crop plants with complex genomes

Studying Magnetic Fields and Dust in M17 Using Polarized Thermal Dust Emission Observed by SOFIA/HAWC

We report on the highest spatial resolution measurement to date of magnetic fields (B-fields) in M17 using thermal dust polarization measurements taken by SOFIA/HAWC+ centered at a wavelength of 154 μm. Using the Davis–Chandrasekhar–Fermi method, in which the polarization angle dispersion calculated using the structure function technique is the quantity directly observed by SOFIA/HAWC+, we found the presence of strong B-fields of 980 ± 230 and 1665 ± 885 μG in the lower-density M17-N and higher-density M17-S regions, respectively. The B-field morphology in M17-N possibly mimics the fields in gravitationally collapsing molecular cores, while in M17-S the fields run perpendicular to the density structure. M17-S also displays a pillar feature and an asymmetric large-scale hourglass-shaped field. We use the mean B-field strengths to determine Alfvénic Mach numbers for both regions, finding that B-fields dominate over turbulence. We calculate the mass-to-flux ratio, λ, finding λ = 0.07 for M17-N and 0.28 for M17-S. These subcritical λ values are consistent with the lack of massive stars formed in M17. To study dust physics, we analyze the relationship between dust polarization fraction, p, emission intensity, I, gas column density, N(H2), polarization angle dispersion function, S, and dust temperature, T d. p decreases with intensity as I −α with α = 0.51. p tends to first increase with T d, but then decreases at higher T d. The latter feature, seen in M17-N at high T d when N(H2) and S decrease, is evidence of the radiative torque disruption effect