291 research outputs found

    An investigation of the academic consulting competence of high school teachers in Vietnam

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    High school students must grapple with a host of issues and encounter difficulties when studying at schools, such as peer pressure, test anxiety, cyberbullying, unhealthy relationships, psychological distress, depression and possibly domestic issues. These obstacles create the need for academic consulting in order for high school students to develop essential skills and then solve problems. This study aims to examine the high school teachers' perceptions and the quality of academic consulting competence in the Vietnamese educational context. This study surveyed 1089 high school students and 289 teachers in Ha Noi and Ho Chi Minh City in Vietnam with the 43-item questionnaire. The main results showed that academic consulting competence had been noticed and trained professionally for high school teachers. Additionally, both students and high school teachers recognized the essential role of high school teachers' academic consulting competence in educational settings

    Effects of different nutrient solutions on growth and flower quality of gerbera (Gerbera jamesonii) grown in hydroponic close system

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    The nutrient solution is the decisive factor for the growth and development of hydroponic plants. This study was conducted to determine the effect of five nutrient solutions, namely, Hoagland, Knop, Hydro Umat F, BKFAST, and Bio-Life, on the growth and development of gerbera (Gerbera jamesonii) in the hydroponic system. The results show that Hydro Umat F is the most suitable solution for planting gerbera in terms of plant height, number of leaves, leaf size, and root volume. In addition, the flower yield of the gerbera plants nourished on Hydro Umat F is also the highest, with 8.7 flowers per plant after five months in the hydroponic system. The flowers have a diameter of 9.8 cm and natural durability of 19.67 days. Meanwhile, gerbera plants stop growing after 15 days in the Bio-Life solution and 30 days in the Knop solution

    CeO2 based catalysts for the treatment of propylene in motorcycle's exhaust gases

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    In this work, the catalytic activities of several single metallic oxides were studied for the treatment of propylene, a component in motorcycles' exhaust gases, under oxygen deficient conditions. Amongst them, CeO2 is one of the materials that exhibit the highest activity for the oxidation of C3H6. Therefore, several mixtures of CeO2 with other oxides (SnO2, ZrO2, Co3O4) were tested to investigate the changes in catalytic activity (both propylene conversion and CO2 selectivity). Ce0.9Zr0.1O2, Ce0.8Zr0.2O2 solid solutions and the mixtures of CeO2 and Co3O4 was shown to exhibit the highest propylene conversion and CO2 selectivity. They also exhibited good activities when tested under oxygen sufficient and excess conditions and with the presence of co-existing gases (CO, H2O)

    Preparation and characterization of magnesium hydroxyapatite coatings on 316L stainless steel

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    Magnesium hydroxyapatite coatings (MgHAp) were deposited on the surface of 316L stainless steel (316L SS) substrates by electrodeposition technique. Different concentrations of Mg2+ ion were incorporated into the apatite structure by adding Mg(NO3)2 into electrolyte solution containing 3×10-2 M Ca(NO3)2, 1.8×10-2 M NH4H2PO4 and   6×10-2 M NaNO3. With Mg2+ concentration 1×10-3 M, the obtained coatings have 0.2 wt% Mg2+. The influences of scanning potential ranges, scanning times to deposit MgHAp coatings were researched. The analytical results FTIR, SEM, X-ray, EDX, thickness and adhension strength showed that MgHAp coatings were single phase of HAp, fibrous shapes, thickness 8.1 µm and adhesion strength 7.20 MPa at the scanning potential ranges of 0÷-1.7 V/SCE and scanning times of 5 scans. Keywords. 316L SS, Electrodeposition, MgHAp

    Fe-MCM-22 zeolites: synthesis and study about the states of iron

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    The Fe-MCM-22 zeolite was successfully synthesized with hexametylenimine template. Several physicochemical techniques (XRD, SEM, BET, AAS, IR and ESR) have been used to characterize this zeolite. Iron exists under three states: isolated ions in tetrahedral lattice positions, in octahedral coordination as isolated ions at cationic positions and as aggregated oxide species or hydroxide phases.Keywords: Fe-MCM-22 zeolite, synthesis, characterization, framework iron

    A short review of fecal indicator bacteria in tropical aquatic ecosystems : knowledge gaps and future directions

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    Given the high numbers of deaths and the debilitating nature of diseases caused by the use of unclean water it is imperative that we have an understanding of the factors that control the dispersion of water borne pathogens and their respective indicators. This is all the more important in developing countries where significant proportions of the population often have little or no access to clean drinking water supplies. Moreover, and notwithstanding the importance of these bacteria in terms of public health, at present little work exists on the persistence, transfer and proliferation of these pathogens and their respective indicator organisms, e.g., fecal indicator bacteria (FIB) such as Escherichia coli and fecal coliforms in humid tropical systems, such as are found in South East Asia or in the tropical regions of Africa. Both FIB and the waterborne pathogens they are supposed to indicate are particularly susceptible to shifts in water flow and quality and the predicted increases in rainfall and floods due to climate change will only exacerbate the problems of contamination. This will be furthermore compounded by the increasing urbanization and agricultural intensification that developing regions are experiencing. Therefore, recognizing and understanding the link between human activities, natural process and microbial functioning and their ultimate impacts on human health are prerequisites for reducing the risks to the exposed populations. Most of the existing work in tropical systems has been based on the application of temperate indicator organisms, models and mechanisms regardless of their applicability or appropriateness for tropical environments. Here, we present a short review on the factors that control FIB dynamics in temperate systems and discuss their applicability to tropical environments. We then highlight some of the knowledge gaps in order to stimulate future research in this field in the tropics

    COPPER-MODIFIED MCM-22 AS CATALYSTS FOR HYDROCARBON SELECTIVE CATALYTIC REDUCTION OF NOX

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    Joint Research on Environmental Science and Technology for the Eart

    Contribution of health workforce to health outcomes: empirical evidence from Vietnam.

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    BACKGROUND: In Vietnam, a lower-middle income country, while the overall skill- and knowledge-based quality of health workforce is improving, health workers are disproportionately distributed across different economic regions. A similar trend appears to be in relation to health outcomes between those regions. It is unclear, however, whether there is any relationship between the distribution of health workers and the achievement of health outcomes in the context of Vietnam. This study examines the statistical relationship between the availability of health workers and health outcomes across the different economic regions in Vietnam. METHODS: We constructed a panel data of six economic regions covering 8 years (2006-2013) and used principal components analysis regressions to estimate the impact of health workforce on health outcomes. The dependent variables representing the outcomes included life expectancy at birth, infant mortality, and under-five mortality rates. Besides the health workforce as our target explanatory variable, we also controlled for key demographic factors including regional income per capita, poverty rate, illiteracy rate, and population density. RESULTS: The numbers of doctors, nurses, midwives, and pharmacists have been rising in the country over the last decade. However, there are notable differences across the different categories. For example, while the numbers of nurses increased considerably between 2006 and 2013, the number of pharmacists slightly decreased between 2011 and 2013. We found statistically significant evidence of the impact of density of doctors, nurses, midwives, and pharmacists on improvement to life expectancy and reduction of infant and under-five mortality rates. CONCLUSIONS: Availability of different categories of health workforce can positively contribute to improvements in health outcomes and ultimately extend the life expectancy of populations. Therefore, increasing investment into more equitable distribution of four main categories of health workforce (doctors, nurses, midwives, and pharmacists) can be an important strategy for improving health outcomes in Vietnam and other similar contexts. Future interventions will also need to consider an integrated approach, building on the link between the health and the development

    STUDY OF NEGATIVE REFRACTIVE INDEX IN Rb FOUR-LEVEL N-TYPE ATOMIC GAS MEDIUM

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    In this work, we study the generation of a negative refractive index based on electromagnetically induced transparency (EIT) in a Rb four-level N-type atomic gas medium. We derive analytic expressions for the relative permittivity and relative permeability of the medium according to the parameters of the probe, pump, and signal laser fields. We then investigate the variation of the real parts of the relative permittivity and relative permeability with respect to the intensity and frequency of the pump and signal laser fields. In the presence of the pump laser beam, the medium becomes transparent to the probe laser beam even in the resonant region. At the same time, the real parts of the relative permittivity and relative permeability are simultaneously negative (i.e., the medium exhibits a negative refractive index) in the EIT spectral domain. In the presence of the signal laser beam, the EIT effect occurs over two different frequency domains of the probe beam, so a negative refractive index is also generated in these two frequency domains. The investigation of the real parts of the relative permittivity and relative permeability with intensity and frequency of the pump and signal laser fields allowed us to find the laser parameters for the appearance of the negative refractive index, which can be useful for experimental observations
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