Published: 2020-02-28

The impact of corporate social responsibility for employees to organisational commitment

Tien D. Mai, Thuy T. T. Nguyen, & Tinh Nguyen
Electronic version: 28 Feb 2020 | DOI: 10.52997/jad.1.01.2020
Abstract | PDF (260.1K)

Abstract

This study explores the factors of corporate social responsibility (CSR) for employees affecting organizational commitment, and then measures the impact of CSR for employees to organizational commitment. The study was conducted by surveying 200 employees working for companies in Ho Chi Minh City. The results of the correlation analysis show that CSR for employees influences the organizational commitment. In addition, the regression analysis shows that more specific results such as job autonomy, benefits (the most influential factor) have positive impacts on “affective commitment” of Vietnamese employees. For “continuance commitment”, besides job autonomy, benefits, the factor "training and development" also shows a positive influence. Meanwhile, the factors related to health and safety, the balance between job and life are not as effective as those in other countries.

Effects of ethephon treatment at pre-harvest stage on leave color, growth time, and sesame seed yield and quality (Sesamum indicum L.)

Tuyen T. X. Vo, & Tan D. Nguyen
Electronic version: 28 Feb 2020 | DOI: 10.52997/jad.4.01.2020
Abstract | PDF (260.1K)

Abstract

The effect of ethephon spray on leaves at pre-harvest stage to accelerate the ripening process of capsules and sesame defoliation was studied. Sesame plant was treated with ethephon at concentrations of 0, 50, 100, 200, 300, 400 and 500 ppm when the capsules on plant began to mature, the seeds turned black. The results showed that ethephon treatment caused yellowing of leaves, accelerated defoliation and the growth time of sesame plants was shortened from 5 to 6 days compared to the control sample. In addition, the ethephon concentration of 50 and 100 ppm caused yellowing of leaves with chlorophyll index measured at 3 days after treatment was 13.5 and 12.7, respectively. At ethephon concentration of 200-500 ppm caused complete yellowing and defoliation of leaves in 3 days after treatment. The leaves of control sample were still green and had chlorophyll index of 22.2. Treatment of ethephon with concentrations of 50-300 ppm did not reduce the yield and lipid content in the seeds compared to the control sample, but from 400 ppm or more caused cracking of capsules, reducing yield and lipid content in the seeds. Ethephon treatment did not affect the number of capsules/plant, number of seeds/capsule, weight of 1000 seeds, protein content and seed color.

Effects of organic fertilizer levels and spray rates of organic solution on tomato yield (Lycopersicum estulentum Mill.)

T. L. Nguyen, & Huy V. Ha
Electronic version: 28 Feb 2020 | DOI: 10.52997/jad.3.01.2020
Abstract | PDF (260.1K)

Abstract

The objective of the experiment was to evaluate effects of organic fertilizer levels and spray rates of organic solution on tomato yield. A 4 x 3 factorial field experiment arranged in a randomized complete block design was conducted in Spring - Summer season 2018 at the experimental site of Faculty of Agronomy (Vietnam National University of Agriculture). The two factors included (1) organic fertilizer rates with four levels (0, 11, 13.5, & 16 tons/ha) and (2) sprayed concentration of HB101 organic solution with three levels (0, 0.15, & 0.3 mL/L). The amount of water used for 1 ha was 10,000 L. The experimental results showed that increased amounts of organic fertilizer and HB101 solution doses positively increased the number of flowers per inflorescence, number of inflorescences per plant, number of fruits per plant, average weight of fruit, and tomato yield. Meanwhile, combinations of 16 tons/ha of organic fertilizer and HB101 solution at the concentrations of 0.3 mL/L and 0.15 mL/L gave the highest tomato yield with 44.0 tons/ha and 42.6 tons/ha, respectively. The highest profit margin obtained with the treatment of non–application of organic sources was 3.8. However, the highest economic profit was obtained with the treatment of 16 tons/ha of organic fertilizer combined with 0.15 mL/L HB101.

Effects of substrates and foliar fertilizer on growth and development of Lisianthus (Eustoma grandiflorum (Raf.) Shinn) in Ho Chi Minh City

Duong T. T. Pham, Cuong C. Nguyen, Duong N. Le, & Ngan T. T. Tran
Electronic version: 28 Feb 2020 | DOI: 10.52997/jad.2.01.2020
Abstract | PDF (260.1K)

Abstract

Lisianthus (Eustoma grandiflorum (Raf.) Shinn) is a favorable flower plant for decoration year-around, especially during New Year holiday. This experiment was conducted in order to evaluate influences of five substrates and three concentrations of foliar fertilizer on growth and development of Lisiathus in Ho Chi Minh City. The obtained results indicated that the plants which were grown best on the substrate mixture of 30% cow dung : 40% coco peat : 20% rice husk ash : 10% soil had better plant height (46.06 cm), number of leaves (63.30 leaf/plant), number of flower buds (14.20 buds/plant) and number of flower (6.17 flowers/plant) than the other treatments. Lisianthus grown on the substrate mixture of 30% cow-dung : 40% coco peat : 20% rice husk ash : 10% soil mixed foliar fertilizer Dau Trau MK 30-10-5 at a concentration of 2.0 g/L was highest in the plant height (46.80 cm) and number of leaves (66.00 leaves/plant). However, the number of flower buds and number of flower were 15.47 buds/plant and 7.53 flowers/plant, respectively when Lisianthus was grown on substrate 30% cow-dung : 40% coco peat : 20% rice husk ash : 10% soil mixed foliar fertilizer at a concentration of 1.0 g/L.

Effects of gamma rays from 60Co source on dwarf Dendrobium cross-breeding

Vinh V. Nguyen, Anh H. Tran, Le V. Bui, & Tri M. Bui
Electronic version: 28 Feb 2020 | DOI: 10.52997/jad.5.01.2020
Abstract | PDF (800.9K)

Abstract

In this research, seeds of DM12x13 dwarf Dendrobium cross-breeding germinated on 1/2 MS medium after 40 days were irradiated by 60Co source with various doses to determine LD50 (Lethal Dose 50%). After LD50 had been determined, protocorms of DM12x13 dwarf Dendrobium cross-breeding was irradiated by gamma rays from 60Co source in 5 doses: 0 Gy (control), 20 Gy, 40 Gy, 60 Gy and 80 Gy, dose rate 90 Gy/h to study the effect of gamma radiation on mutagenicity and evaluate the growth of these mutations in vitro. The result showed that the lethal dose of hybrid DM12x13 Dendrobium protocorm under the effect of 60Co gamma ray was 68 Gy. Survival ratio, growth and the ability to growth of plants reduced in higher doses and dead ratio were 100% when irradiated more than 80 Gy after 7 months. The effective doses for treating protocorm of DM12x13 crossbred lines were 20, 40 and 60 Gy. These doses were suitable for increased frequency of variation with generating wide-spread, diverse in structure and color of stems and leaves.

Effects of nitrogen and potassium application rates on growth and yield of garlic (Allium sativum L.) planted in Ninh Thuan province

Nguyen H. Pham, & Thu D. Nguyen
Electronic version: 28 Feb 2020 | DOI: 10.52997/jad.6.01.2020
Abstract | PDF (260.1K)

Abstract

The objectives of the study were to determine the optimum application rates of nitrogen and potassium for good growth, high yield and economic efficiency of garlic cultivated on the sandy soil of Ninh Thuan province in Winter-Spring season 2018 - 2019. The experiment was laid out in strip-plot design with three replications. Vertical-strip plot factor (A) was four application rates of nitrogen (A1: 150; A2: 200; A3: 250, and A4: 300 kg N/ha). Horizontal-strip plot factor (B) was for three application rates of potassium (B1: 90; B2: 120, and B3: 150 kg K2O/ha). The study results showed that the combined application of 200 kg N/ha and 120 kg K2O/ha on the base of 80 kg P2O5 and 20 tons of cow manure resulted in higher plant height (58.2 cm), number of leaves (8.7 leaves/plant), the highest diameter of garlic bulb (3.5 cm), the highest average bulb weight (15.8 g/bulb) with a total of 17.1 cloves/bulb, the high commercial garlic bulb yield (13.42 tons/ha), and the highest profit (373,665,800 VND/ha/crop) with the profit margin was 2.15.

Induced spawning of Asian bumblebee catfish (Pseudomystus siamensis Regan, 1913)

Binh T. T. Vo, Truc T. T. Nguyen, Tuan V. Vo, Tu V. Nguyen, & Chau M. Pham
Electronic version: 28 Feb 2020 | DOI: 10.52997/jad.7.01.2020
Abstract | PDF (260.1K)

Abstract

Asian bumblebee catfish (Pseudomystus siamensis Regan, 1913) is an indigenous and economically valuable species in southern provinces of Vietnam. It is being exploited for food and ornamentation. This study used fish pituitary gland (FPG), human chorionic gonadotropin (HCG) and luteinizing hormone releasing hormone analogue (LHRHa) to induce spawning of the fish. The three spawning inducers affected on final oocyte maturation (FOM) and ovulation (FOMO) of females. The optimal revolving dose to induce FOM and FOMO was 10 mg/kg for FPG, 4.000 UI/kg for HCG and 120 μg/kg of female for LHRHa. The suitable periods of egg stripping and artificial insemination were from 9 - 11 h post resolving injection (hpri). Maximum spawning response was obtained with the optimal revolving dose of LHRHa (120 μg/kg). At the suitable stripping period (10 hpri) the rates of spawning, egg fertilization, egg hatching, larval survival, and relative fecundity were 64.5%, 70%, 44.5%, 39.3%, and 38,500 egg/kg of female, respectively.

Rearing white leg shrimp larvae (Litopenaeus vannamei Boone, 1931) with concentrated diatom (Thalassiosira sp.)

Nhien V. Tran, H. N. Ho, Le T. M. Lai, & Thanh H. Nguyen
Electronic version: 28 Feb 2020 | DOI: 10.52997/jad.8.01.2020
Abstract | PDF (260.1K)

Abstract

The objective of the experiment was to determine the best type of algae for growth, survival rate and the metamorphosis time of white leg shrimp larvae. The experiment consisted of five treatments: dried Spirulina sp. (NT 1), fresh Chaetoceros sp. (NT 2), fresh Thalassiosira sp. (NT 3), Thalassiosira sp. in concentrated form (NT 4) and Thalasiosira sp. in paste form (NT 5). The larvae at Nauplius VI were stocked in 0.5 m3tank at the stocking density of 200 inds/L. The care regime was applied according to the popular process at the National Breeding Center for Southern Marine Aquaculture. After 10 days of stocking, the water parameters in all treatments were in a suitable range for the growth of larvae. The larvae in NT 4 showed the best body length, survival rate, metamorphosis time and were significant difference compared to the remaining treatments (P < 0.05). Whereas NT 5 was not significantly different (P > 0.05) compared to NT 2 in body length and NT 3 in metamorphosis time. NT 1 showed the worst these characteristics to the other treatments. In general, the use of concentrated Thalassiosira sp. for rearing white leg shrimp larvae gives good results, which should be commonly applied.

Effects of type and concentration of alginate on microencapsulation characteristics of lime essential oil (Citrus aurantifolia) produced by extrusion-dripping methods

Vinh Truong, Phuong T. Nguyen, Phuong N. M. Ta, Phuong T. Nguyen, & Nhung T. C. Pham
Electronic version: 28 Feb 2020 | DOI: 10.52997/jad.9.01.2020
Abstract | PDF (260.1K)

Abstract

The extrusion-dripping method to produce alginate-calcium beads for microencapsulation of lime oil (Citrus aurantifolia) was carried out in this study. The experimental range of alginate concentration was from 1 to 4%. Above 1% alginate concentration, viscosity was pseudoplastic behavior. The size (1.52 - 1.57 mm) and sphericity (above 95%) of the beads were maximum at alginate concentration of 2 - 3%. The extrusion-dripping method was not applicable when alginate concentration was over 3.5% due to the high viscosity resulting in low sphericity. The two types of alginates with a protein content of 9% (alg1) and 2% (alg2) had the same microencapsulation yield of 73 - 74%. However, the solid recovery of alg2 (98.99%) was much higher than that of alg1 (52.71%). This is because alg2 has a higher purity and if it is used in production, it is easier to control the content of active ingredients and reduce the amount of organic waste that is harmful to the environment compared to alg1.

Applying QGIS software to manage database of street and house number in Binh Tho ward, Thu Duc district, Ho Chi Minh City

Xuan T. Vo, Thy N. Nguyen, Linh D. T. Truong, Duy T. Nguyen, Khoi H. Nguyen, & Trang T. Nguyen
Electronic version: 28 Feb 2020 | DOI: 10.52997/jad.12.01.2020
Abstract | PDF (260.1K)

Abstract

Today, the rapid development of urban areas has led to the explosion of data volumes in land use change. The present development of infrastructure and housing has caused many difficulties in urban management, especially information of street name and house number. Therefore, the management and provision of information of street name and house number in a scientific and effective way is an urgent demand for all agencies, organizations and individuals in our society. Geographic information system (GIS) is developing increasingly and continuously and applied in many fields; QGIS is a new open source code software with many features, considered as one of the most powerful tools in designing and analyzing spatial database. Applying this software to manage database of name street and housing number will be better in managing construction and infrastructure development in urban areas which are suitable with the strategy of establishing smart city and e-government in our city and nation. The results of this study showed that the present and oriental organization of address built successfully a database of streets name, houses number and used Python programming language in developing the tool to manage and look up the information with functions such as look up, update and map interaction of Binh Tho ward, Thu Duc district, Ho Chi Minh City. The test results indicate that this tool is very useful in managing and searching information on street name, house number related to information on land parcels’ information on cadastral base.

Estimation of air emissions and applying GIS technology to build emissions map from area source in Ho Chi Minh City

Q. B. Ho, Trinh P. B. Nguyen, Khue H. N. Vu, Hang T. T. Nguyen, & Tam T. Nguyen
Electronic version: 28 Feb 2020 | DOI: 10.52997/jad.11.01.2020
Abstract | PDF (260.1K)

Abstract

The actual status of air pollution in HCM City is alarming and causing many impacts on human health. The sources of air pollution are classified into four main sources: industrial (point source), transport (line source), area and biological source. The study focused on emission inventory for the area source, including domestic cooking activities, restaurants, cafeterias, petrol stations, photocopy, construction materials stores, construction works, garages, pagodas, straw burning... Emissions inventory method make accurate, reliable and well-defined assessment decisions that show that the use of large amounts of coal and charcoal produces large amounts of gaseous pollutants: TSP, NO2, SO2, CO, CH4 and NMVOC... in which household activities account for about 90% of total emissions and 38% TSP amount of total emissions in the source. Application of GIS tools to develop emission maps for identifying high emission areas. The aim of the study was to point out the main cause of emissions in the source area and areas with high emissions (such as District 3, District 4, District 8, Binh Chanh and Cu Chi) so that solutions created to minimize emissions from the burning of fossil fuel for cooking activities of Ho Chi Minh City’s people would be economical and highly effective...

Assessing the current status of water sources for domestic and agricultural purposes in Ia Grai district, Gia Lai province

Tuan Q. Le, Han T. N. Le, & Quy N. Le
Electronic version: 28 Feb 2020 | DOI: 10.52997/jad.10.01.2020
Abstract | PDF (260.1K)

Abstract

Ia Grai district is located in the remote area of Gia Lai province. The income mostly relies on agricultural activities. However, the water shortage for agriculture is an issue and the irrigation much relies on the seasonal rainfall. This study aimed to figure out the demand for water use and other sources of water for irrigation. Household interview, water quality testing and field survey were conducted at 3 communes: Ia Kha, Ia Hrung and Ia To due to their largest agricultural area. The results showed that surface water had good quality; groundwater was polluted by microorganism but in the acceptable levels. All the water indicators met the national standard for the domestic purpose (column A1) and for agricultural irrigation (QCVN 39:2011/BTNMT). Based on the current demand for water use, the amount of water needs in 2020 was estimated as well as the solutions for water management and protection was also proposed for Ia Grai district.