DSpace Collection:
https://dspace.ctu.edu.vn/jspui/handle/123456789/2268
2024-03-28T20:21:38ZEnhancing farmers’ perception on fish quality management systems
https://dspace.ctu.edu.vn/jspui/handle/123456789/46851
Title: Enhancing farmers’ perception on fish quality management systems
Authors: Le, Nguyen Doan Khoi
Abstract: In order to ensure and improve quality in the agro-food sector, quality systems have to undergo constant change: simple end of the pipe monitoring is being replaced by management-oriented regimes (Enneking et al., 2007). Increasing, farmers, too, are required to implement quality systems. A variety of quality assurance systems has been developed for use at the primary production level over the last few years. They differ widely, however, with respect to their requirement levels, regional scope of application, degree of integration into the supply chain or their institutional supports. The supposition that certified farmers’ perceptions for participating in the various systems are not necessarily identical for this study. The aim of this study is to ascertain non-system specific factors that influencing the acceptance of quality systems. This article provides an overview of evaluating three Pangasius culture systems namely ponds, cages and net-pen enclosures at the farm level.2019-01-01T00:00:00ZCordycepin Isolated from Cordyceps militaris: Its Newly Discovered Herbicidal Property and Potential Plant-Based Novel Alternative to Glyphosate
https://dspace.ctu.edu.vn/jspui/handle/123456789/39603
Title: Cordycepin Isolated from Cordyceps militaris: Its Newly Discovered Herbicidal Property and Potential Plant-Based Novel Alternative to Glyphosate
Authors: Tran, Ngoc Quy; Tran, Dang Xuan; Andriana, Yusuf; Tran, Hoang-Dung; Tran, Dang Khanh; Teschke, Rolf
Abstract: There is currently much interest in finding new phytochemicals among plants and fungi as nature-based alternatives to replace problematic herbicides such as glyphosate, which are preferentially used in agricultural production n. We discovered striking herbicidal potency in Cordyceps militaris (L.) and identified cordycepin as its principal plant growth inhibitor. Cordycepin obtained as an ethyl acetate extract was subjected to column chromatography and evaluated for its bioassay-guided phytotoxic capacity against Raphanus sativus (radish), showing a maximum inhibition on germination and growth of radish (IC₅₀ = 0.052-0.078 mg/mL). Gas chromatography-mass spectrometry (GC-MS) (m/z: 251.2) and liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) ([M + Na]+ m/z: 274.1; [M + H]+ m/z: 252.1) analyses confirmed cordycepin as the major component of the tested column fraction (55.38%). At 0.04 mg/mL, cordycepin showed 3.8-5.9- and 3.3-3.7-fold greater inhibition of the germination and growth of radish than benzoic acid (BA) and glyphosate, respectively. Compared with BA, isolated cordycepin reduced plant chlorophyll and carotenoid contents (2.0-9.5 -fold), while proline, total phenolic and total flavonoid contents were increased 1.2-1.8-fold. Finally, cordycepin promoted electrolyte leakage and malondialdehyde accumulation in radish aerial parts. Thus, cordycepin successfully isolated from Cordyceps militaris is a highly potent plant growth inhibitor with pending worldwide patent and may become a potential plant-based novel alternative to the disputed glyphosate.2019-01-01T00:00:00ZThe Role of Pseudomonas in Heterotrophic Nitrification: A Case Study on Shrimp Ponds (Litopenaeus vannamei) in Soc Trang Province
https://dspace.ctu.edu.vn/jspui/handle/123456789/39602
Title: The Role of Pseudomonas in Heterotrophic Nitrification: A Case Study on Shrimp Ponds (Litopenaeus vannamei) in Soc Trang Province
Authors: Tran, Thanh Trung; Bott, Nathan J.; Lam, Nhan Dai; Nguyen, Nam Trung; Hoang, Thi Dang Oanh; Le, Duc Hoang; Le, Lam Tung
Abstract: Based on a total of 6,295,650 sequences from the V3 and V4 regions (16S ribosomal RNA), the composition of the microorganism communities in the water of three Litopenaeus vannamei (Decapoda, Whiteleg shrimp; Soc Trang, Vietnam) ponds were identified. Pseudomonas (10–20.29%), Methylophilus (13.26–24.28%), and Flavobacterium (2.6–19.29%) were the most abundant genera. The total ammonia (TAN) concentration (p = 0.025) and temperature (p = 0.015) were significantly correlated with the relative abundance of Pseudomonas in two bacterial communities (ST1, ST4), whereas the predictive functions of microorganism communities based on 16S rRNA gene data was estimated using Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUST), which showed that nitrogen metabolism was significantly negatively correlated (p = 0.049) with TAN concentration. The abundance of Pseudomonas and nitrogen metabolism increased with a decrease in TAN concentration. The correlation between TAN concentration and the abundance of Pseudomonas was followed by the isolation, and heterotrophic nitrifying performance analysis was used to confirm our findings. Six Pseudomonas strains capable of heterotrophic nitrification were isolated from the three water samples and showed a complete reduction of 100 mg/L NH4Cl during a 96-h cultivation. These results indicate the potential of applying Pseudomonas in shrimp ponds for water treatment.2019-01-01T00:00:00ZYouth's Perceptions of Innovation Start-Up Business
https://dspace.ctu.edu.vn/jspui/handle/123456789/39601
Title: Youth's Perceptions of Innovation Start-Up Business
Authors: Le, Nguyen Doan Khoi
Abstract: This paper focuses on youth's decision process to become innovation entrepreneurs. The first part of the paper delivers the problem statement and a literature review of latest (empirical) contributions in the field of entrepreneurship. The present survey indicated the view of the potential entrepreneurs as well as already successful youth's entrepreneurs – indicating suitable attempts for possibilities of improvement. In addition, it was useful to track youth's entrepreneurship along the enterprise life-cycle to reveal specific strengths and weaknesses in specific phases of enterprise development.2019-01-01T00:00:00Z