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Green microalgae Haematococcus pluvialis is best known for astaxanthin production. The cultivation of H. pluvialis involves two main phases, namely green vegetative stage and cyst stage with astaxanthin accumulation. In fact, the growth of H. pluvialis in the vegetative stage is one of the most important parts in the entire cultivation process. The aim of the study is to investigate the influence of temperature, inoculum size, CO 2 concentration and light emitting diodes (LEDs) on the specific growth rate, cell density and dry weight of H. pluvialis in the vegetative stage. Results indicated that the temperature from 25 to 28 0 C and the inoculum size from 3×10 4 cells.ml-1 were suitable for the growth of the studied strain. Illumination with red light LEDs (630 nm) at 80 μE.m-2 .s-1 , the highest specific growth rate (µ) was 0.197 day-1 and the maximal density was of 2.87×10 5 cells.ml-1. A concentration of 5% CO 2 (v/v) was the optimal dose for the growth of this strain. Under the condition of both 5% CO 2 and illumination with red light LEDs at 80 μE.m-2 .s-1 , the specific growth rate was 0.242 day-1 and the cell density was 4.28×10 5 cells.ml-1. Illumination with only blue LEDs (430 nm) at 120 μE.m-2 .s-1 stimulated the astaxanthin accumulation with a maximum content at 2.36 µg.ml-1 .

Non-Performing Loans (NPLs) are a significant issue for all banks in Vietnam, attracting considerable attention from scholars. Our research aims to nd out the factors that affect the NPLs of Vietnamese commercial banks. The study uses Pooled Ordinary Least Square (OLS), Fixed effect, Random effect, and Generalized Least Square to examine secondary data of 28 commercial banks annually for the period 2008-2019. Consistent with previous research, the main finding shows that macroeconomic and microeconomic factors impact NPLs. Remarkably, provision for credit risk (PCR) has a significantly positive effect on the NPL ratio. Besides, foreign investor ownership (FOR) and bank size (SIZE) negatively affect the NPL ratio. Especially, for the positive correlation between foreign investor ownership and bank performance, the commercial bank should expand to enhance operational efficiency. Regarding macro factors, the results conclude that gross domestic product (GDP) growth and the unemployment rate (UEP) have a significantly negative relationship on NPLs. Therefore, the State Bank of Vietnam and the banks need to understand the leading causes as they directly relate to the banks in the context of the prevailing economic environment.This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution, and reproduction in any medium provided the original work is properly cited.

Practicum is an excellent chance for university students to apply their knowledge in a real-world professional setting. Unlike other majors, Vietnamese English major students are generally not trained to work in a particular area. Therefore, the causes of their unsatisfactory experiences during practicum are different from those of students with other majors. This current study was designed with a mixed-methods approach to enlist the causes of English-majored students’ unsatisfactory experiences during their practicum. Two hundred twenty-two interns majoring in English studies/linguistics responded to an open-ended question. The results showed that students’ low self-efficacy and short internship duration were the two leading causes of unsatisfactory experiences during the practicum. Based on the qualitative data analyses, the students were found struggling to complete their assigned tasks as well as expected. Additionally, the short duration prevented them from gaining more professional experience. As a result, some implications for improving the program’s quality are discussed in this paper.

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