Predicting the bearing capacity of pile installed into cohesive soil concerning the spatial variability of SPT data (A case study)

Nowadays, in situ tests have played a viable role in geotechnical engineering and construction technology. Besides lab tests conducted on undisturbed soil samples, many different kinds of in-situ tests were used and proved to be more efficient in foundation design such as pressuremeter PMT, cone penetration test CPT, standard SPT, etc. Among them, a standard penetration test (SPT for short) is easy to carry out at the site. For decades, it has proved reliable to sandy soil, but many viewpoints and opinions argued that the test was not appropriately applicable to cohesive soil because of scattered and dispersed data of SPT blow counts through different layers. This paper firstly studies how reliable the SPT data can predict the physical and mechanical properties; secondly, the soil strength is determined in terms of corrected N-SPT values, and finally the bearing capacity of a pile penetrating cohesion soil. By analyzing data from 40 boreholes located in 18 projects in Ho Chi Minh City, South VietNam, coefficients of determination between SPT numbers and physical and mechanical properties of different soil kinds are not the same: R2 = 0.623 for sand, =0.363 for sandy clay and =0.189 for clay. The spatial variability of soil properties is taken into account by calculating the scale of fluctuation θ=4.65m beside the statistically-based data in horizontal directions. Finally, the results from two theoretical approaches of predicting pile bearing capacity were compared to those of finite element program Plaxis 3D and static load test at site. Correlation between the capacity computed by using corrected N-values instead of soil strength and results of static load test has proved to be well suitable in evaluating the bearing capacity of driven and jack-in piles, particularly installing in the cohesive soil using the SPT blows.

Cloning, expression and purification of fructosyl amino acid oxidase (FAOX) in Escherichia Coli

Introduction: The level of serum HbA1c is an indicator of the average blood sugar level in the last three months. HbA1c can be quantified using assays involving the enzyme fructosyl amino acid oxidase (FAOX). This study aims to produce GST-tagged FAOX-TE (GST/FAOX-TE), a thermal stable and specific variant of FAOX, for future application studies. Materials and methods: The E. coli strains DH5α and BL21 (DE3) were used as cloning and expression hosts, respectively. The FAOX-TE sequence was synthesized at IDT (US) and clonned into pGEX-4T3 vector, which was confirmed by Colony PCR. The expression was induced at 16°C, 0.5 mM IPTG in LB media containing 50 µg/ml ampicilin. The protein expression profile was analyzed by SDS-PAGE. The cell pellet was sonicated and purified by Glutathione Sepharose 4 Fast Flow (Cytiva, US). The catalytic activity of GST/FAOX-TE with fructosyl valine was determined using high performance anion exchange chromatography with pulsed amperometry detection (HPAEC-PAD). Results: The fusion protein was successfully expressed in Escherichia coli using the plasmid pGEX-4T3 and purified to high purity 93%. Recombinant GST/FAOX-TE was shown to be active on fructosyl valine. Conclusions: Active GST/FAOX-TE was successfully expressed in E. coli BL21 (DE3) and purified, which will be used for future development of biosensors for fructosyl valine quantification.

Adsorption of ammonium, nitrite, and nitrate onto rice husk biochar for nitrogen removal

This study aims to investigate the adsorption capacity of ammonium NH4+, nitrite NO2- and nitrate NO3- onto rice husk biochar (RHB) obtained from 550 °C pyrolysis temperature in the context of using low-cost absorbent for recirculating aquaculture system (RAS). Raw RHB at its original size 5–8 mm has been choosen for testing its adsorption capacity as well as several key material properties (pHPZC, surface area, and elemental analysis). From surface functional group analysis, there existed the O–H group (at frequency 3443 cm-1), –CH3 (2360 cm-1), and either –C=O or C=C group (in the range of frequency 1600–1650 cm-1) as well as –COOH (1456 cm‒1) that helped enhance chemical adsorption. The experimental adsorption data has been roughly consistent with Langmuir and Freundlich models that used to calculate the maximum saturated monolayer adsorption capacity Q0max of ammonium, nitrite, and nitrate were 0.1003, 0.2477, and 0.1290 mg/g respectively. Therefore, RHB could be a potential candidate for biofilter application in both targets cost-efficient and sustainable that worth applied at scale.

Direct embryogenesis from anther culture of hot chilli Capsicum annuum L.

In Viet Nam, local varieties of chili have a distinctive aroma and pungency. However, the generation of pure lines from pollen culture in local hot chilli has been very limited reported. Therefore, this study was to relate flower bud size with microspore developmental stages and the culture media have concentration changed of growth regulator effects on the in vitro androgenesis. Flower buds were randomly collected and visually divided into three stage based on both petal and sepal size. Then anther was cultured on MS basal medium with different concentration of hormones NAA changed 0.1 - 0.7 mg/L and kinetin changed 1.0 - 3.0 mg/L, BA changed 0.5 - 1.5 mg/L. The results showed that bud flower have anthers are light violet in color, 2.5 mm long, consisted of anthers with 80 % uni-nucleate and 20 % bi-nucleate microspores were selected. In induction culture media, it was observed that MS medium with 2.0 mg/L Kinetin and 0.5 mg/L NAA gave higher embryo frequency. MS medium with 1 mg/L BA is the best medium for embryo germination and inducting shoots. And ½ MS medium for shoot elongation and rooting.

Isolation, identification and investigation some biochemical properties of lactic acid bacteria from “Mam sac chua” and “Com me” in Tien Giang province

The objective of this study was isolate, identify and investigate some biochemical properties of strains of lactic acid bacteria from “com me” and “mam sac chua” in Tien Giang province. Nineteen strains of LAB were isolated from four “com me” and three “mam sac chua” samples. They have characterized of lactic acid bacteria such as: halo rings in MRS agar environment added 0,85% CaCO3, rod-shaped cells, Gram positive, catalate and oxidase negative. All 19 strains of LAB were able to produce lactic acid in MRS broth (1,01 – 2,23 mg/ mL after 24 hours). Three strains of LAB were isolated from “com me” were able to produce lactic acid in MRS broth at salt concentration of 0, 2, 4 and 6% (0,57 – 1,29 mg/ mL after 24 hours). In particular, strains of LAB were coded ML3 and ML4 produced the highest lactic acid and VB strain was the most salinity tolerance. Therefore, these three srains were choosed to identify species by molecular biology technique. The results of identification were Staphylococcus piscifermentans VB, Lactobacillus plantarum ML3 and Lactobacillus plantarum ML4 because they are 99% homologous to S. piscifermentans and L. plantarum.

Rational protein design for enhancing thermal stability of industrial enzymes

Enzymes possessing many excellent properties such as high selectivity, consuming less energy, and producing less side products or waste have been widely applied as biocatalysts in pharmaceutical production and many industries such as biofuel, biomaterials, biosensor, food, and environmental treatment. Although enzymes have shown its potential as biocatalysts for many industrial applications, natural enzymes were not originated for manufacturing process which requires harsh reaction conditions such as high temperature, alkaline pH, and organics solvents. It was reported that reduction of final conversion of several enzymatic reactions was declined at high temperature. Protein engineering to improve the enzymes’ thermostability is crucial to extend the use of the industrial enzymes and maximize effectiveness of the enzyme-based procesess. Various industrial enzymes with improved thermostability were produced through rational protein engineering using different strategies. This review is not aimed to cover all successful rational protein engineering studies. The review focuses on some effective strategies which have widely used to increase the thermostability of several industrial enzymes through introduction of disulfide bonds and introduction of proline.

Research antioxidant activity of chitooligosacchride by UV-VIS absorption spectrocopy

Chitosan with 80% degree of deacetylation was hydrolyzed by cellulase of Trichoderma viride to prepare chitooligosaccharides (COSs) by the fractionation of the COSs with ultrafiltration membrane. The antioxidant activities of the COSs were clarified in this study by reducing power and free radical scavenging ability assay by UV-VIS absorption spectrum. The results show that the COS 1 (10,000-5,000 Da), COS 2 (5,000-3,000 Da), COS 3 (3,000-1,000 Da) and COS 4 (less than1,000 Da) segments have antioxidant properties.The antioxidant activitives of the COSs increased with the increment of concentration, and they also depended on molecular weight.

Shoots formation from gynosinesis Cucumis sativus l.

Haploid plants achieve through androgenesis or gynogenesis. In gynogenesis method, the ovary or ovule are used as explants induct haploid plants. Female flower one day before flowering of Cucumis sativus L. are collected. Cold pretreatment of ovaries at 4°C up to 24 hours and culture under dark conditions. Significantly enhanced callus induction response is compared with cultures under 4-week cultured on CBM medium supplemented with various concentration of TDZ 0.01-0.04 mg/L. After 4 weeks, ovaries are transferred to medium with kinetin 0.05 – 0.20 mg/L. Then, ovaries were transferred to medium supplemented with BA: IAA 3:1. Finally, green ovaries were transferred to BA 1.5 mg/L and GA3 1.5 mg/L. The results showed that ovary induction has best affected on CBM with TDZ 0.03 mg/L with 11 callus/sample. Ovaries developed on kinetin 0.1 mg/L with 7.4 callus/sample. Ovaries become green and had leaves and roots formation on BA: IAA (3 mg/L: 1 mg/L). 11 plantlets were harvested from ovary culture after 12-week culture on CBM supplemented with BA 1.5 mg/L and GA3 1.5 mg/L.

The initial study of EBNA-2 polymorphisms in nasopharyngeal carcinoma in Vietnam

Epstein-Barr virus (EBV) infection is the main cause of Nasopharyngeal Carcinoma (NPC). EBNA-2, one of the most important genes participating in the formation of NPC, also helps EBV evade an attack on the immune system. EBNA-2 has 4 variants including E2-A, E2-B, E2-C and E-2D, of which E2-A and E2-C are the characterized variants for NPC. This study aimed to evaluate the variations of EBNA-2 in NPC biopsy samples of Vietnamese patients. This initial study used 10 biopsy samples, which were positively confirmed to NPC, collected from Cho Ray Hospital. Nested PCR – nucleotide sequencing was applied to analyze the variants of EBNA-2. The results showed that 8 out of 10 samples, accounting for 80%, were positive to EBNA-2. Additionally, only two variants, E-2A and E-2C were detected in our study, in which, E2-A subtype was identified as the predominant subtype. These findings would provide initial data about potential contribution of EBNA-2 polymorphisms to etiology of NPC in Vietnamese population.

Edge detection based on augmented lagrangian method for lowquality medical images

Medical images are useful for the treatment process. They contain a lot of information on displaying abnormalities in your body. The contour of medical images is a matter of interest. In there, edge detection is a process prepared for boundaries. Therefore, the edge detection of medical images is very important. Other previous methods must sacrifice time for the accurate results. It is because the medical images in the real world have many impurities. In this paper, I propose a method of detecting edges in medical images which have impurities by using augmented lagrangian method to improve the Canny algorithm. My algorithm improves the ability to detect edges faster. Compared with other recent methods, the proposed method is more efficient.