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

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

Estimation of forest Carbon Stocks in Ba Be National Park, Bac Kan province, Vietnam

Climate change and an increase in the greenhouse effect are a matter of global concern. One of reasons for this phenomenon is the increase in greenhouse gases, especially CO2. Therefore, the authors investigated CO2 absorption from forests of 45 plots in Ba Be National Park, characterized by 3 forest states as rich, medium and poor forest, rehabilitated forest after exploitation to estimate carbon sequestration of the forest. In which, the carbon stock of rich forest reaches 273.17 tones/ha, the medium forest is 136.23 tones/ha and the poor forest, rehabilitated forest is 42.06 tones/ha. With a forest growth rate of 1.8% per year, the carbon sequestration in Ba Be National Park for 3 forest states is about 16,499 tones per year. This will contribute to improve environmental quality, reducing greenhouse gas emissions and creating a scientific basis for managers to develop a payment mechanism of forest carbon sequestration services

A characterization of the algebraic degree in semidefinite programming

In this article, we show that the algebraic degree in semidefinite programming can be expressed in terms of the coefficient of a certain monomial in a doubly symmetric polynomial. This characterization of the algebraic degree allows us to use the theory of symmetric polynomials to obtain many interesting results of Nie, Ranestad and Sturmfels in a simpler way.Comment: 14 page

Agricultural restructure policy in Vietnam and practical application for sustainable development in agriculture

Recently, effective agricultural policies necessitate sustainable development in the agricultural sector, which necessitates frequent research and the attention of policymakers. Consequently, this study investigates the effect of agricultural restructuring policies on agricultural import, agricultural export, agricultural employment, agricultural irrigation land, and agricultural land on the sustainable development of agriculture in Vietnam. From 1991 to 2021, the researchers extracted secondary data from secondary sources such as World Development Indicators (WDI). The researchers also used the non-linear autoregressive distributed lag (NARDL) method to examine the relationships between the variables. The results revealed that agricultural restructuring policies regarding agricultural import, agricultural exports, agricultural employment, agricultural irrigation land, and agricultural land have a positive correlation with Vietnam's agriculture's sustainable development. The research assists policymakers in formulating regulations for achieving sustainable agricultural development by implementing effective agricultural restructuring policies.Mai Thi Huyen (Bac Giang Agriculture and Forestry University (BAFU)), Nguyen Thi Xuan Huong (Viet Nam National University of Forestry (VNUF)), Nguyen Van Song (Viet Nam National University of Agriculture (VNUA)), Nguyen Thi Hai Yen (College of Economics, Vinh University (VU)), Nguyen Dang Que National Academy of Public Administration (NAPA))Includes bibliographical references

STUDY ON ANTIOXIDANT ACTIVITIES OF THE AERIAL PARTS AND SOME COMPOUNDS ISOLATED FROM Archidendron clypearia ((Jack) I. Niels Part 2. ISOLATING, DETERMINING STRUCTURE AND ANTIOXIDANT CAPABILITY OF SOME COMPOUNDS FROM ETHYL ACETATE EXTRACT

The antioxidant activity in vitro of methanol extract of Archidendron clypearia was evaluated by in vitro tests on isolated liver cells of mouses with ED50 value ​​ of 2.18 μg/mL compared to that of curcumin of 1.87 µg/mL. Using combined chromatographic methods, four compounds were isolated from chloroform extract of the Archidendron clypearia. Their structures were elucidated to be daucosterol, 1-octacosanol, docosenoic acid, and methyl gallate by 1D- and 2D-NMR spectroscopic methods and in comparison with those reported in the literature. This is the first report of these compounds from the plant. All four compounds showed quite high antioxidant activity, for which methyl gallate was the highest one

EULER CHARACTERISTIC OF TANGO BUNDLES

We are interested in a vector bundle constructed by Tango (1976). The Tango bundle is an indecomposable vector bundle of rank n-1 on the complex projective space P^n. In particular, we show that the Euler characteristic of the Tango bundle on P^n is equal to 2n-1

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

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)

The Relationship between Budget Revenue - expenditure and Inflation in Vietnam: Viewed from the Results of Quantitative Analysis

The research examines the relationship between budget revenue expenditure and inflation in Vietnam, with time series data on budget revenue expenditure and the consumer price index (CPI) (representing the inflation variable in Vietnam). Data were collected from the International Financial Statistics (IFS-IMF), General Statistics Office (GSO) in the period of 2005-2022. The author used Eview software to build a linear relationship log-log of budget revenue - -expenditure and CPI in the case of the Vietnamese economy. Quantitative analysis results show that when budget revenue increased by 1%, CPI increased by 0.249674%, when budget expenditure increased by 1%, CPI increased by 0.298316%. Raising budget revenue to raise budget expenditure will result in higher inflation during the research period in Vietnam. From the theoretical basis, research overview, and quantitative analysis results, the research team makes some recommendations for fiscal policy in Vietnam in the current context

Managerial Implications for Enhancing Working Motivation and Loyalty of Workers of Enterprises in Dong Nai Province

Purpose: The article aims to assess the factors affecting employees' work motivation and loyalty in enterprises in Dong Nai province. On that basis, the authors propose managerial implications to improve employees' work motivation and loyalty at enterprises in Dong Nai province.   Theoretical framework: Motivation and loyalty is reflected in the employee's intention to stay with the organization for a long time, even when receiving a more attractive salary offer from other organizations. Work refers to the positive effects of work on each person, related to the challenges at work, the opportunity to develop personal abilities, and the enjoyment of doing the job.   Design/Methodology/Approach: Quantitative method was carried out through direct interviews with 1000 workers using a questionnaire designed based on the results of the qualitative research step. The data were processed by SPSS 20.0 and Amos software. The reliability of the scales was tested using Cronbach's Alpha reliability coefficient, EFA exploratory factor analysis, confirmatory factor analysis (CFA), and structural model analysis (SEM) in Dong Nai province from June 2022 to December 2022.   Findings: The study's contribution is to identify the factors of corporate culture, social responsibility, and management capacity to promote work motivation and employee loyalty.   Research, practical & social implications:  Classical theories are used to study work motivation, add 3 factors, find out the remaining problems, and propose management implications to improve the work motivation of employees' activities soon.   Originality/Value: The results are also scientific evidence and are essential for researchers and policymakers for businesses to apply research results to improve employee motivation and loyalty of employees

Determinants of Working Motivation and Loyalty of Workers: A Case Study of Enterprises in Dong Nai Province

Purpose: The article aims to determine factors affecting employees' work motivation and loyalty in enterprises in Dong Nai province.   Theoretical framework: Research theory on work motivation and employee loyalty. Work motivation is the motivation of people to work enthusiastically, helping them promote their inner potential and overcome challenges and difficulties to complete the work in the best way.   Design/Methodology/Approach:  The research method of this study is a combination of qualitative research methods and quantitative research methods. Qualitative research: group discussions were conducted with 30 business experts with extensive experience in human resource management and longtime business directors in Dong Nai. Quantitative analysis was carried out with an expected sample size of 1000 enterprises in enterprises, selected by convenient sampling method.   Findings: The study contributes to a new survey of the factors affecting the work motivation and loyalty of employees in enterprises in Dong Nai province as a reference for academic studies and other in the field of human resource management.   Research, practical & social implications: The research results of the research paper serve as a scientific basis for business leaders in Dong Nai province to propose reasonable policies to improve employees' work motivation and loyalty at enterprises in Dong Nai province.   Originality/Value:  The paper's originality and value help managers contribute to the study to add a suitable work motivation and loyalty model for today's Vietnamese business leaders