A new root-knot nematode, Meloidogyne moensi n. sp. (Nematoda : Meloidogynidae), parasitizing Robusta coffee from Western Highlands, Vietnam

A new root-knot nematode, parasitizing Robusta coffee in Dak Lak Province, Western Highlands of Vietnam, is described as Meloidogyne moensi n. sp. Morphological and molecular analyses demonstrated that this species differs clearly from other previously described root-knot nematodes. Morphologically, the new species is characterized by a swollen body of females with a small posterior protuberance that elongated from ovoid to saccate; perineal patterns with smooth striae, continuous and low dorsal arch; lateral lines marked as a faint space or linear depression at junction of the dorsal and ventral striate; distinct phasmids; perivulval region free of striae; visible and wide tail terminus surrounding by concentric circles of striae; medial lips of females in dumbbell-shaped and slightly raised above lateral lips; female stylet is normally straight with posteriorly sloping stylet knobs; lip region of second stage juvenile (J2) is not annulated; medial lips and labial disc of J2 formed dumbbell shape; lateral lips are large and triangular; tail of J2 is conoid with rounded unstriated tail tip; distinct phasmids and hyaline; dilated rectum. Meloidogyne moensi n. sp. is most similar to M. africana, M. ottersoni by prominent posterior protuberance. Results of molecular analysis of rDNA sequences including the D2-D3 expansion regions of 28S rDNA, COI, and partial COII/16S rRNA of mitochondrial DNA support for the new species status

Policy uncertainty, derivatives use, and firm-level FDI

We explore the link between uncertainty in economic policy, firm level FDI, and firm hedging behaviour - building upon a newspaper-based index of economic policy uncertainty (EPU). We find that relative difference in EPU between home and host country has a significant relationship with FDI. Firms increase their FDI level in countries, which have a low level of EPU relative to their home country. In addition, firms use derivatives more intensively in response to an increase in EPU. Interestingly, the link between EPU and corporate derivatives use varies according to the type of firm. Domestic MNCs make the most effective use of derivatives to hedge against EPU exposure

Internet traffic prediction using recurrent neural networks

Network traffic prediction (NTP) represents an essential component in planning large-scale networks which are in general unpredictable and must adapt to unforeseen circumstances. In small to medium-size networks, the administrator can anticipate the fluctuations in traffic without the need of using forecasting tools, but in the scenario of large-scale networks where hundreds of new users can be added in a matter of weeks, more efficient forecasting tools are required to avoid congestion and over provisioning. Network and hardware resources are however limited; and hence resource allocation is critical for the NTP with scalable solutions. To this end, in this paper, we propose an efficient NTP by optimizing recurrent neural networks (RNNs) to analyse the traffic patterns that occur inside flow time series, and predict future samples based on the history of the traffic that was used for training. The predicted traffic with the proposed RNNs is compared with the real values that are stored in the database in terms of mean squared error, mean absolute error and categorical cross entropy. Furthermore, the real traffic samples for NTP training are compared with those from other techniques such as auto-regressive moving average (ARIMA) and AdaBoost regressor to validate the effectiveness of the proposed method. It is shown that the proposed RNN achieves a better performance than both the ARIMA and AdaBoost regressor when more samples are employed

Trust under the prospect theory and quasi-hyperbolic preferences: a field experiment in Vietnam

We conduct a field experiment in Vietnamese villages to explore the effect of the prospect theory and of quasi-hyperbolic time preferences parameters on trust and trustworthiness. We find that risk aversion, loss aversion and present bias do not influence trustors’ decisions, but a higher time discounting increases the amount sent in the South of Vietnam and probability weighting decreases it in the North. If time discounting and loss aversion do not influence trustworthiness, we show that more risk averse and less present biased trustees return a higher share of their wealth to the trustors. These results suggest that adopting another perspective than the expected utility theory and the exponential discounting approach of time preferences enables to uncover some channels by which risk and intertemporal time preferences influence trusting behavior in societies