Pre-harvest factors affecting fruit quality in sweet oranges with an emphasis on albedo breakdown

Albedo breakdown known as creasing, a physiological disorder, due to abnormal separation of cells leading to the formation of irregular fractures in the white tissue (albedo) causing the creases of sweet orange rind. It causes serious economic losses to the sweet orange growers in Australia and in other orange producing areas of the world.Fruit quality, particularly albedo breakdown has been influenced by various factors such as plant water relations, genetic factors, plant nutritional status and plant growth regulators. My research investigated the development of the incidence and the severity of albedo breakdown during fruit maturation and ripening, the effects of severity of albedo breakdown on fruit quality among locations and cultivars of ‘Navel’ sweet orange. I also elucidated the influence of deficit regulated irrigation, exogenous application of surfactants added in calcium solution, exogenous application of boron and the role of ethylene in the incidence of albedo breakdown, textural properties of the rind and fruit quality of ‘Navel’ sweet oranges.The incidence and the severity of albedo breakdown increased rapidly after commercial harvest. The incidence and severity of albedo breakdown in ‘Washington Navel’ orange differed from location to location, with the lowest at Harvey as compared to three other locations. Regardless of locations and cultivars, the severity of albedo breakdown did not affect juice content, soluble solids concentration, titratable acidity, ascorbic acid, citric acid and malic acid except for decreasing succinic acid and increasing tartaric acid. Locations and cultivars significantly influenced these fruit quality parameters.The application of deficit irrigation (50% and 75% water supply of control trees) improved fruit quality in terms of increased soluble solids concentrations and acidity levels without affecting percentage of juice, pH of juice, ascorbic acid and individual organic acids in ‘Navelina’ sweet orange. The enhancement of the uptake of Ca in leaf, rind, and pulp of the fruit and the reduction in the incidence of albedo breakdown were obtained with the application of different surfactants added into aqueous solutions of 2% Ca(NO[subscript]3)[subscript]2 starting from 81 days after full bloom (DAFB) at 10-day intervals. Among four tested surfactants, ‘Tween 20’ (0.05%) was the most effective in enhancing Ca uptake, reducing albedo breakdown and improving textural properties of rind and fruit firmness while maintaining the other important fruit quality attributes in ‘Washington Navel’ sweet orange.The foliar application of boron enhanced the concentration of boron and calcium in the leaf, rind and pulp. The single spray application of boron in early summer at 600 mg.L[superscript]-1 was the most effective in increasing boron concentration in the leaf, rind and pulp of fruit, reducing the incidence of albedo breakdown and improving textural properties of rind and fruit firmness without affecting any the other fruit quality attributes in ‘Washington Navel’ sweet orange.Rind of fruit with albedo breakdown produced the higher ethylene production than the normal fruit. The exogenous application of ethylene inhibitors including AVG (200 mg.L[superscript]-1) and CoSO[subscript]4 (300 mg.L[superscript]-1) reduced the incidence of albedo breakdown and improved the rind textural properties in ‘Washington Navel’ sweet orange. Ethylene seems to be involved in the incidence of albedo breakdown.In conclusion, the severity of albedo breakdown did not affect the major attributes of fruit quality in ‘Navel’ sweet oranges. The applications of deficit irrigation, exogenous 2% Ca(NO[subscript]3)[subscript]2 containing ‘Tween 20’ as a surfactant and the exogenous spray application of boron (600 mg.L[superscript]-1) influenced the incidence and severity of albedo breakdown without affecting other fruit quality parameters. Ethylene seems to be associated with the incidence of albedo breakdown in ‘Washington Navel’ sweet orange

The Current Status of Secondary School Teacher’s Perception of Happiness in Nam Dinh Province during the Implementation Period of the 2018 General Education Program

In the current context of a major revolution in the Vietnamese education system, teachers’ perception of happiness makes an important criterion in evaluating effectiveness of the changes made to educational programs. The initial investigation of the positive effects of this renovation was conducted on the scale of Nam Dinh province and the results show multidimensional sources of information. In addition to positive information, there is still information that raises many questions for leaders to pay attention to. The outcome of the investigation suggests the evaluation of “The job is meaningful” is 3.10 out of 5 points, which is the lowest in assessment criteria. Meanwhile, the rates for “Completely disbelieve” and “Slightly disbelieve” in happiness of their profession in the future take up a large proportion (24.4%). However, other criteria namely “Being satisfied with current position” and “Feeling motivated with the job” received higher evaluation scores, respectively 4.05/5 points and 4.11/5 points. Via the results of the research, the author is looking forward to appropriate actions taken by the Ministry of Education and Training of Vietnam with a view to enhancing the perception of happiness among teachers

Robust Adaptive Control of 3D Overhead Crane System

In this chapter an adaptive anti-sway controller for uncertain overhead cranes is proposed. The system model including the system uncertainties and disturbances is introduced firstly. Next, the adaptive controller which can guarantee tracking the desired position of the trolley as well as the anti-sway of the load cable is established. In this chapter, the system is proven to be input-to-state stable (ISS) which is supported by Lyapunov technique. The proposed algorithm is verified by using Matlab/Simulink simulation tool. The simulation results shown that the presented controller gives the good performances (i.e., fast transient response, position tracking, and low swing angle) when there exist system parameters variation as well as input disturbances

CHẤT LƯỢNG MÔI TRƯỜNG TRẦM TÍCH TẦNG MẶT PHÍA NAM VỊNH NHA TRANG

Analyzed results of 11 surface sediment samples collected in June 2012 in the south of  Nha Trang bay showed that: The contents of the organic materials and heavy metals in the sediments were considerably various (organic C: 0.12 - 1.46% , organic N: 135.8 - 987.7 µg/g, total P: 44.0 - 551.1 µg/g; Zn: 2.2 - 28.7 µg/g; Cu: 2.6 - 22.2 µg/g, Pb: 2.7 - 28.1 µg/g, Fe: 514 -         17,337 µg/g) and correlated with the rate of mud fraction; Organic carbon and heavy metal contents tended to be higher in areas near Tre and Tam Islands and lower value in off - shore areas; Among studied areas: i) There was no significant difference in hydrocarbon content (from 115 - 188 µg/g); ii). Related to microbiology, coliform density (from 0 - 8,197 MPN/100g) was highest at Mieu and Mot Islands. Generally, the surface sediments in Nha Trang bay, in terms of organic materials and heavy metals, were suitable for the aquatic life. However, there was the lightly increasing trend in organic matters (N and P) from 2007 to 2012.Kết quả phân tích 11 mẫu trầm tích bề mặt thu thập tháng 6/2012 ở khu vực phía nam vịnh Nha Trang cho thấy: Hàm lượng nguyên tố carbon, nitơ và photpho trong hợp chất hữu cơ và kim loại nặng trong trầm tích dao động mạnh (C: từ 0,12% đến 1,46%, N: 135,8 - 987,7 µg/g, tổng P: 44,0 - 551,1 µg/g, Zn: 2,2 - 28,7 µg/g, Cu: 2,6 - 22,2 µg/g, Pb: 2,7 - 28,1 µg/g, Fe: 514 - 17.337 µg/g) theo xu thế đồng biến với tỉ lệ cấp hạt bột, sét trong trầm tích (0 - 99,75%); Tại khu vực gần Hòn Tre và Hòn Tằm, hàm lượng C và các kim loại nặng có xu thế cao ở gần bờ, nhưng thấp ở xa bờ; Giữa các khu vực có mẫu phân tích: i) Không có sự khác biệt lớn về hàm lượng hydrocarbon (từ 115 - 188 µg/g); ii) Liên quan đến tình trạng nhiễm bẩn vi sinh, mật độ coliform (0 - 8197 MPN/100 g) cao nhất ở khu vực Hòn Miếu và Hòn Một. Đánh giá chung, chất lượng môi trường trầm tích khu vực phía nam vịnh Nha Trang còn khá tốt, hàm lượng các chất hữu cơ và kim loại nặng trong trầm tích đều phù hợp cho đời sống thủy sinh. Tuy nhiên, vật chất hữu cơ (N và P) có xu thế tăng nhẹ từ năm 2007 đến 2012

CHẤT LƯỢNG TRẦM TÍCH BỀ MẶT ĐÁY Ở VÙNG BIỂN XUNG QUANH QUẦN ĐẢO THỔ CHU, KIÊN GIANG

Analysis results of surface sediment samples collected in October, 2013 in the coral reefs and soft bottom habitats around Tho Chu islands showed that silt - clay - ration, pH, Eh, organic matter contents, heavy metals, oil-grease and total sulphur in sediments ranged widely (silt - clay - ration: 1.68 - 39.28%; pH: 7.15 - 8.18; Eh: (-121.0) - (-58) mV; org C: 0.07 - 0.7%; org N: 149.4 - 242.2 μg/g; total P: 95.8 - 795.7 μg/g; Zn: 3.2 - 17.4 μg/g; Cu: 2.8 - 10.0 μg/g; Pb: 2.9 - 17.1 μg/g; oil-grease: 89 - 153 μg/g and total S: 437.6 - 3078.3 μg/g). The contents of organic matters and heavy metals (Zn, Cu) in soft bottom habitats were relatively higher than those in the coral reefs while pH values were lower. There were no differences in contents of total S, Pb, oil-grease and silt - clay - ration of sediments in two ecosystems. Overall, the sediment quality in the coral reefs and soft bottom habitats around Tho Chu islands was very good, the contents of organic matters and heavy metals in the sediments were suitable for aquatic life conservation.Kết quả phân tích các mẫu trầm tích bề mặt đáy thu thập vào tháng 10/2013 tại các rạn san hô và hệ sinh thái đáy mềm xung quanh quần đảo Thổ Chu cho thấy: Tỉ lệ cấp hạt bùn-sét, pH, Eh, hàm lượng các chất hữu cơ, kim loại nặng, dầu mỡ và Sts trong trầm tích dao động trong phạm vi tương đối rộng (tỉ lệ cấp hạt bùn-sét: 1,68 - 39,28%; pH: 7,15 - 8,18; Eh: (-121,0) - (-58) mV; Chc: 0,07 - 0,7%; Nhc: 149,4 - 242,2 µg/g; Pts: 95,8 - 795,7 µg/g; Zn: 3,2 - 17,4 µg/g; Cu: 2,8 - 10,0 µg/g; Pb: 2,9 - 17,1 µg/g; dầu mỡ: 89 - 153 µg/g và Sts: 437,6 - 3.078,3 µg/g); Hàm lượng các chất hữu cơ và kim loại nặng (Zn, Cu) trong trầm tích hệ sinh thái đáy mềm tương đối cao hơn so với trầm tích các rạn san hô trong khi giá trị pH có xu thế ngược lại. Hàm lượng Sts, Pb, dầu mỡ và tỉ lệ cấp hạt bùn-sét trong trầm tích tại hai hệ sinh thái này không có sự khác biệt. Nhìn chung, chất lượng môi trường trầm tích tại các rạn san hô và các hệ sinh thái đáy mềm xung quanh quần đảo Thổ Chu còn rất tốt, hàm lượng các chất hữu cơ và kim loại nặng trong trầm tích đều phù hợp cho đời sống thủy sinh

Data Driven Customer Segmentation for Vietnamese SMEs in Big Data Era

Almost Vietnamese big businesses often use outsourcing services to do marketing researches such as analysing and evaluating consumer intention and behaviour, customers’ satisfaction, customers’ loyalty, market share, market segmentation and some similar marketing studies. One of the most favourite marketing research business in Vietnam is ACNielsen and Vietnam big businesses usually plan and adjust marketing activities based on ACNielsen’s report. Belong to the limitation of budget, Vietnamese small and medium enterprises (SMEs) often do marketing researches by themselves. Among the marketing researches activities in SMEs, customer segmentation is conducted by tools such as Excel, Facebook analytics or only by simple design thinking approach to help save costs. However, these tools are no longer suitable for the age of data information explosion today. This article uses case analysing of the United Kingdom online retailer through clustering algorithm on R package. The result proves clustering method’s superiority in customer segmentation compared to the traditional method (SPSS, Excel, Facebook analytics, design thinking) which Vietnamese SMEs are using. More important, this article helps Vietnamese SMEs understand and apply clustering algorithm on R in customer segmenting on their given data set efficiently. On that basis, Vietnamese SMEs can plan marketing programs and drive their actions as contextualizing and/or personalizing their message to their customers suitabl

Transformation Chlorophyll a of Spirulina platensis to Chlorin e6 Derivatives and Several Applications

BACKGROUND: Spirulina platensis contains a large amount of chlorophylls, chlorophyll a, that are starting materials to synthesize functionalized chlorins. Chlorin e6 (Ce6) as well as its derivatives are second generation sensitizers using in photodynamic therapy (PDT) of various cancers. In this study, we transfer chlorophyll a of S. platensis to Ce6derivatives and determine their several applications. AIM: to evaluate the effects of Ce6 derivatives to treat cancer cells. METHODS: Ce6 trimethylester was created from methyl pheophorbide a2 in S. platensis provided by the Hidumi Company, Nghe An province, Viet Nam. Hela cells were incubated with Ce6 trimethylester and the irradiated with the diode laser dose of 1.2 J/cm2/min through the system of filters £ 650 nm. MTT assay and clonogenic assay were used to determine survival rate and cloning efficiency of cells. Antimicrobial effect of Ce6 trimethylester with halogen light were studied with Propionibacterium acnes VTCC 0218 and Staphylococcus aureus VTCC 0173. RESULTS: From dry biomass (700 g) of S. platensis, after extracting chlorophyll a and methanolysis, 4.2 g of methyl pheophorbide a was obtained. The reaction to give Ce6 trimethylester with 82% yield was performed with potassium hydroxide (KOH) in MeOH/THF/CHCl3. After irradiation with a 650 nm laser at 1.2 J, the cell viability in all samples decreased with Ce6 trimethylester treatment, the survival declining trend of Hela cells treated with Ce6 trimethylester were proportional when concentration of Ce6 trimethylester increased. The rate of colony formation was declined as the concentration of Ce6 trimethylester treated was increased. The growth of both S. aureus and P. acnes can be inactivated by Ce6 trimethylester PDT. The MIC99 value against P. acnes VTCC 0218 and S. aureus VTCC 0173 of Ce6 trimethylester with halogen light was 1.25 μg/ml. CONCLUSION: The Ce6 trimethylester from S. platensis cultivated in Viet Nam could be used as a potential photosentizer for photodynamic therapy for treatment of cancer and acne

PURIFICATION OF RAVE COMPLEX FROM Saccharomyces cerevisiae USING FLAG TAG-AFFINITY PURIFICATION METHOD

RAVE (Regulator of the H+-ATPase of the Vacuolar and Endosomal membranes) is an            essential factor of assembly and reversible disassembly of V-ATPase. RAVE complex has three subunits, which are Rav1p, Rav2p and Skp1p. There are few studies on RAVE so it is very             important to study structure of RAVE complex to understand more about the regulation of the assembly and reassembly at V-ATPase. In this study the RAVE complex was purified by affinity purification by fussing FLAG tag to subunit Rav1p or Rav2p. Experimental process: yeast cells were incubated in 8 L YEPD medium at 30 oC, 200 rpm (OD600nm around of 3). Furthermore                   harvested cells were broken by a French pressure cell disruptor at 25,000 p.s.i in TBSE (50 mM Tris/Cl, 150 mM NaCl, 1 mM EDTA, pH 7.4) with 1 mm PMSF. The cell lysate was centrifuged at 20,000 xg for 20 minutes at 4 oC. Then, the supernatant, was achieved by centrifugation, and loaded onto a small column contained 1 ml of anti-FLAG M2 gel. After washing anti-FLAG column with TBSE, RAVE complex was eluted with TBSE containing 100 µg/ml FLAG               peptides. The results showed RAVE complex purification from strain with FLAG tag fused in                 C-terminus of Rav2 is better than RAVE complex purification from the yeast strain S. cerevisiae with FLAG tag fused in N-terminus of Rav1 or C-terminus of Rav1

Respiratory viruses in individuals with a high frequency of animal exposure in southern and highland Vietnam

Active surveillance for zoonotic respiratory viruses is essential to inform the development of appropriate interventions and outbreak responses. Here we target individuals with a high frequency of animal exposure in Vietnam. Three-year community-based surveillance was conducted in Vietnam during 2013-2016. We enrolled a total of 581 individuals (animal-raising farmers, slaughterers, animal-health workers, and rat traders), and utilized reverse transcription-polymerase chain reaction to detect 15 common respiratory viruses in pooled nasal-throat swabs collected at baseline or acute respiratory disease episodes. A respiratory virus was detected in 7.9% (58 of 732) of baseline samples, and 17.7% (136 of 770) of disease episode samples (P <.001), with enteroviruses (EVs), rhinoviruses and influenza A virus being the predominant viruses detected. There were temporal and spatial fluctuations in the frequencies of the detected viruses over the study period, for example, EVs and influenza A viruses were more often detected during rainy seasons. We reported the detection of common respiratory viruses in individuals with a high frequency of animal exposure in Vietnam, an emerging infectious disease hotspot. The results show the value of baseline/control sampling in delineating the causative relationships and have revealed important insights into the ecological aspects of EVs, rhinoviruses and influenza A and their contributions to the burden posed by respiratory infections in Vietnam.Peer reviewe

The impacts of lead recycling activities to human health and environment in Dong Mai craft village, Hung Yen, Vietnam

Lead (Pb) recycling activities in Dong Mai village, Chi Dao commune, Van Lam district, Hung Yen province have been taking place for more than 30 years. The development of recycling activities contributed to the improvement of the local economics. However, along with economic development, Dong Mai craft village is facing to serious pollution. Soil, air and water polluted by lead (Pb) caused food containing Pb at higher levels than allowed limit from 20 to 40 times. The pollution had the bad effect on human health in this village. The investigation results showed that 100 % of employee who participated on melting lead and 63.5 % of local children were poisoned by Pb. Besides, the local people got diseases relating to skin, eyes, etc. This situation requires the provincial authorities to find immediate solutions to reduce the impacts of Pb recycling activities to environment and human.Hoạt động tái chế chì của thôn Đông Mai, xã Chỉ Đạo, huyện Văn Lâm, tỉnh Hưng Yên đã diễn ra hơn 30 năm nay. Sự phát triển của nghề tái chế đã làm góp phần cải thiện kinh tế của địa phương. Tuy nhiên, cùng với sự phát triển kinh tế, làng nghề Đông Mai đã và đang đối mặt với ô nhiễm môi trường nghiêm trọng. Môi trường đất, nước không khí bị ô nhiễm bởi chì (Pb) dẫn đến thực phẩm nhiễm chì ở hàm lượng cao hơn mức cho phép từ 20- 40 lần. Sự ô nhiễm gây ra những ảnh hưởng xấu tới sức khỏe của người dân làng nghề. Kết quả điều tra cho thấy 100% công nhân tham gia nấu chì và 63.5% trẻ em địa phương bị nhiễm độc chì. Bên cạnh đó, người dân địa phương còn bị mắc của các loại bệnh ngoài da, bệnh về mắt, …. Tình trạng này đòi hỏi chính quyền địa phương phải tìm ra giải pháp khẩn cấp để giảm thiểu tác động của những hoạt động tái chế chì tới môi trường và con người