Molecular and antigenetic characterization of <i>Streptococcus suis serotype</i> 2 isolates in Central Vietnam

Streptococcus suis is a Gram-positive bacterium with clinical relevance in pigs and is emerging in human. There are 35 S. suis serotypes have been distinguished to date, of which serotype 2 is most commonly associated with disease in human and pigs, worldwide. Recently, S. suis emerged as a zoonotic agent in human in contact with infected pigs or with their products. More recently, several studies from Southeast Asia demonstrated that S. suis can cause adult endocarditis, septicemia, arthritis and especially meningitis with high fatality rate and severe neurological sequelae. Multilocus enzyme electrophoresis, restriction endonuclease analysis with HaeIII, ribotyping, and pulsed-field gel electrophoresis have been used to determine S. suis strains epidemiological relationships. Characterization of the 16S-23S ribosomal (r) DNA intergenic spacer region (ITS) has also been used to compare bacterial strains and to identify species within the genus Streptococcus, including S. suis. In this study, a specific and sensitive PCR assay for fast detection of S. suis serotype 2 is crucial to meningitis treatment based on the S. suis serotype 2 cps2J gene was developed and evaluated for diagnosis in meningitis patients hospitalized in central Viet Nam. The intergenic spacer region was amplified by traditional PCR from strains obtained in this study and sequenced. ITS - based phylogenetic analysis is also presented and discussed. We also identified and characterized the main immunodominant antigens of Streptococcus suis serotype 2 based on the immunoproteomics approach

A STUDY OF INDONESIA’S STOCK MARKET: HOW PREDICTABLE IS IT?

Using monthly data from January 1995 to December 2017, this paper tests whetherIndonesian stock index returns are predictable. In particular, we use eight macrovariables to predict the Indonesian composite and six sectoral index returns using thefeasible generalized least squares estimator. Our results suggest that the Indonesianstock index returns are predictable. However, the predictability depends not only onthe macro predictor used but also on the indexes examined. Second, we find that themost popular predictor is the exchange rate, followed by the interest rate. Finally, ourmain findings hold for a number of robustness tests.Using monthly data from January 1995 to December 2017, this paper tests whetherIndonesian stock index returns are predictable. In particular, we use eight macrovariables to predict the Indonesian composite and six sectoral index returns using thefeasible generalized least squares estimator. Our results suggest that the Indonesianstock index returns are predictable. However, the predictability depends not only onthe macro predictor used but also on the indexes examined. Second, we find that themost popular predictor is the exchange rate, followed by the interest rate. Finally, ourmain findings hold for a number of robustness tests

Environmental Economic Hydrothermal System Dispatch by Using a Novel Differential Evolution

This paper proposes the Novel Differential Evolution (NDE) method for solving the environmental economic hydrothermal system dispatch (EEHTSD) problem with the aim to reduce electricity generation fuel costs and emissions of thermal units. The EEHTSD problem is constrained by limitations on generations, active power balance, and amount of available water. NDE applies two modified techniques. The first one is modified mutation, which is used to balance global and local search. The second one is modified selection, which is used to keep the best solutions. When performing this modified selection, the proposed method completely reduces the impact of crossover by setting it to one. Moreover, the task of tuning this factor can be canceled. Original Differential Evolution (ODE), ODE with the first modification (MMDE), and ODE with the second modification (MSDE), and NDE were tested on two different hydrothermal systems for comparison and evaluation purposes. The performance of NDE was also compared to existing methods. It was indicated that the proposed NDE is a very promising method for solving the EEHTSD problem

TERRORIST ATTACKS AND CORPORATE INVESTMENT IN INDONESIA

Using yearly data from 1997 to 2017, this paper studies the effect of terrorism (number of attacks) on corporate investment in Indonesia. Applying an investment-type model, we show that firms reduce their capital expenditure due to an increase in the number of terrorist attacks. On average, a one standard deviation increase in the number of terrorist attacks reduces corporate investment by 9.23%. We also find heterogenous reactions of firms to terrorism across different sectors and different panels based on firm characteristics. Finally, our main results remain consistent after performing several robustness tests

Optimal generation for wind-thermal power plant systems with multiple fuel sources

In this paper, the combined wind and thermal power plant systems are operated optimally to reduce the total fossil fuel cost (TFFC) of all thermal power plants and supply enough power energy to loads. The objective of reducing TFFC is implemented by using antlion algorithm (ALA), particle swarm optimization (PSO) and Cuckoo search algorithm (CSA). The best method is then determined based on the obtained TFFC from the three methods as dealing with two study cases. Two systems with eleven units including one wind power plant (WPP) and ten thermal power plants are optimally operated. The two systems have the same characteristic of MFSs but the valve loading effects (VLEs) on thermal power plants are only considered in the second system. The comparisons of TFFC from the two systems indicate that CSA is more powerful than ALA and PSO. Furthermore, CSA is also superior to the two methods in terms of faster search process. Consequently, CSA is a powerful method for the problem of optimal generation for wind-thermal power plant systems with consideration of MFSs from thermal power plants

Minimize electricity generation cost for large scale wind- thermal systems considering prohibited operating zone and power reserve constraints

Wind power plants (WPs) play a very important role in the power systems because thermal power plants (TPs) suffers from shortcomings of expensive cost and limited fossil fuels. As compared to other renewable energies, WPs are more effective because it can produce electricity all a day from the morning to the evening. Consequently, this paper integrates the optimal power generation of TPs and WPs to absolutely exploit the energy from WPs and reduce the total electricity generation cost of TPs. The target can be reached by employing a proposed method, called one evaluation-based cuckoo search algorithm (OEB-CSA), which is developed from cuckoo search algorithm (CSA). In addition, conventional particle swarm optimization (PSO) is also implemented for comparison. Two test systems with thirty TPs considering prohibited working zone and power reserve constraints are employed. The first system has one wind power plant (WP) while the second one has two WPs. The result comparisons indicate that OEB-CSA can be the best method for the combined systems with WPs and TPs

A STUDY OF INDONESIA’S STOCK MARKET

Using monthly data from January 1995 to December 2017, this paper tests whether Indonesian stock index returns are predictable. In particular, we use eight macro variables to predict the Indonesian composite and six sectoral index returns using the feasible generalized least squares estimator. Our results suggest that the Indonesian stock index returns are predictable. However, the predictability depends not only on the macro predictor used but also on the indexes examined. Second, we find that the most popular predictor is the exchange rate, followed by the interest rate. Finally, our main findings hold for a number of robustness tests

Ureaplasma urealyticum and Mycoplasma genitalium detection and sperm quality: A cross-sectional study in Vietnam

Background: Ureaplasma urealyticum (U. urealyticum) and Mycoplasma genitalium (M. genitalium) may colonize the male genital tract. However, the negative effects of these bacteria on overall sperm quality, including semen pH, sperm concentration, motility, morphology, and total sperm count remain unclear. Objective: This study aimed to determine the presence of genital U. urealyticum and M. genitalium in semen and evaluate the effect of these organisms on sperm quality. Materials and Methods: A cross-sectional study was conducted on 380 men from infertile couples at a tertiary university hospital from July 2017 to June 2018. Semen quality was analyzed according to the World Health Organization 2010 standard, and U. urealyticum and M. genitalium were detected in the semen samples using polymerase chain reaction. Results: 338 men (88.9%) presented with at least one abnormal semen parameter. The detection rates of U. urealyticum and M. genitalium were 16.05% and 0.79%, respectively. There was no significant difference between the Ureaplasma-positive group and the Ureaplasma-negative group in terms of sperm characteristics. Sperm motility and sperm vitality in the Mycoplasma-positive group were much lower than those in the Mycoplasma-negative group (p = 0.02 and p &lt; 0.001, respectively). Conclusion: The presence of U. urealyticum in the semen of infertile men did not affect the sperm characteristics. Although the positive rate of M. genitalium was low, colonization by these bacteria was more likely to negatively affect sperm quality. Key words: Ureaplasma urealyticum, Mycoplasma genitalium, Infertility, Spermatozoa

“I can't get it out of my mind” - Why, how, and when crisis rumination leads entrepreneurs to act and pivot during crises

Why do some entrepreneurs pivot their business models in a crisis, while others are more passive? Integrating Conservation of Resources theory with work on crisis rumination, we developed a micro-level model to explain why entrepreneurs who are under strain due to a crisis, as indicated by experiencing crisis rumination, adopt an active approach – i.e., using active coping and engaging in pivoting. Moreover, prevention-focused entrepreneurs who are habitually more sensitive to losses are especially stimulated by crisis rumination to pivot to prevent (further) resource losses. We tested our model in an experiment and an eight-month longitudinal study with entrepreneurs during an inflation crisis