Some characters of bacterial cellulases in goats' rumen elucidated by metagenomic DNA analysis and the role of fibronectin 3 module for endoglucanase function

Nguyen, Khanh Hoang Viet,Dao, Trong Khoa,Nguyen, Hong Duong,Nguyen, Khanh Hai,Nguyen, Thi Quy,Nguyen, Thuy Tien,Nguyen, Thi Mai Phuong,Truong, Nam Hai,Do, Thi Huyen Asian Australasian Association of Animal Productio 2021 Animal Bioscience Vol.34 No.5

Objective: Fibronectin 3 (FN3) and immunoglobulin like modules (Ig) are usually collocated beside modular cellulase catalytic domains. However, very few researches have investigated the role of these modules. In a previous study, we have sequenced and analyzed bacterial metagenomic DNA in Vietnamese goats' rumen and found that cellulase-producing bacteria and cellulase families were dominant. In this study, the properties of modular cellulases and the role of a FN3 in unique endoglucanase belonging to glycosyl hydorlase (GH) family 5 were determined. Methods: Based on Pfam analysis, the cellulases sequences containing FN3, Ig modules were extracted from 297 complete open reading frames (ORFs). The alkaline, thermostability, tertiary structure of deduced enzymes were predicted by AcalPred, TBI software, Phyre2 and Swiss models. Then, whole and truncated forms of a selected gene were expressed in Escherichia coli and purified by His-tag affinity column for assessment of FN3 ability to enhance enzyme activity, solubility and conformation. Results: From 297 complete ORFs coding for cellulases, 148 sequences containing FN3, Ig were identified. Mostly FN3 appeared in 90.9% beta-glucosidases belonging to glycosyl hydrolase family 3 (GH3) and situated downstream of catalytic domains. The Ig was found upstream of 100% endoglucanase GH9. Rarely FN3 was seen to be situated downstream of X domain and upstream of catalytic domain endoglucanase GH5. Whole enzyme (called XFN3GH5 based on modular structure) and truncate forms FN3, XFN3, FN3GH5, GH5 were cloned in pET22b (+) and pET22SUMO to be expressed in single and fusion forms with a small ubiquitin-related modifier partner (S). The FN3, SFN3 increased GH5 solubility in FN3GH5, SFN3GH5. The SFN3 partly served for GH5 conformation in SFN3GH5, increased modules interaction and enzyme-soluble substrate affinity to enhance SXFN3GH5, SFN3GH5 activities in mixtures. Both SFN3 and SXFN3 did not anchor enzyme on filter paper but exfoliate and separate cellulose chains on filter paper for enzyme hydrolysis. Conclusion: Based on these findings, the presence of FN3 module in certain cellulases was confirmed and it assisted for enzyme conformation and activity in both soluble and insoluble substrate.

Inverse MR and Dual-AMR Phenomena in Co/CoO/Ag/Co Sandwiches

Nguyen Anh Tuan,Luong Van Su,Hoang Quoc Khanh,Nguyen Anh Tue,Nguyen Thi Luyen 한국물리학회 2018 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.72 No.7

Band-form Co/CoO/Ag/Co sandwiches were prepared using radio-frequency magnetron sputtering. The sandwiches had rather thick Co (tCO = 63 nm) and Ag (tAg = 2 ÷ 65 nm) layers and a super-thin paramagnetic cobalt monoxide (CoO) layer (< 1 nm) inserted in the Co/Ag interface. The sandwiches exhibited anomalous magnetoresistance (MR) behavior depending on the tAg value. Inverse magnetoresistance (IMR) effect was observed only at thin tAg values of 2 nm and 6 nm, whereas the dual-anisotropic MR (dual-AMR) occurred at thicker tAg values of 12 nm, 25 nm and 65 nm. A superposition of the dual-AMR and the weak IMR effects was obtained at the thickest Ag layer of 65 nm. The origin of these anomalous MR behaviors was discussed to show the prominent role of the CoO layer and large thickness of the Co and Ag layers.

Bi-layers Red-emitting Sr2Si5N8:Eu2+ Phosphor and Yellow-emitting YAG:Ce Phosphor: A New Approach for Improving the Color Rendering Index of the Remote Phosphor Packaging WLEDs

Nguyen Huu Khanh Nhan,Tran Hoang Quang Minh,Tan N. Nguyen,Miroslav Voznak 한국광학회 2017 Current Optics and Photonics Vol.1 No.6

Due to optimal advances such as chromatic performance, durability, low power consumption, highefficiency, long-lifetime, and excellent environmental friendliness, white LEDs (WLEDs) are widely usedin vehicle front lighting, backlighting, decorative lighting, street lighting, and even general lighting. In thispaper, the remote packaging WLEDs (RP-WLEDs) with bi-layer red-emitting Sr2Si5N8: Eu2+ and yellowemittingYAG:Ce phosphor was proposed and investigated. The simulation results based on the MATLABsoftware and the commercial software Light Tools indicated that the color rendering index (CRI) of bi-layerphosphor RP-WLEDs had a significant increase. The CRI had a considerable increase from 72 to 94. Inconclusion, the results showed that bi-layer red-emitting Sr2Si5N8:Eu2+ and yellow-emitting YAG:Cephosphor could be a prospective approach for manufacturing RP-WLEDs with enhanced optical properties.

Influence of Red Y2O3:Eu3+ Phosphor Concentration to the Multi-Chip White LEDs Color Rendering Ability

Nguyen Huu Khanh Nhan,Tran Hoang Quang Minh,Nguyen Doan Quoc Anh 보안공학연구지원센터 2016 International Journal of Database Theory and Appli Vol.9 No.4

In this paper, a novel solution and application of the red Y2O3:Eu3+ dopant phosphor for enhancing color rendering index to more 86 for multi-chip white LED lamps (MCW-LEDs), which have correlated color temperature (CCT) of 7700 K, 6600 K, 5600 K, are presented. Then the effect of the concentration of Y2O3:Eu3+ phosphor on the color rendering index (CRI) is simulated, analyzed and demonstrated. After that the lumen output of MCW-LEDs depended on concentration Y2O3:Eu3+ phosphor is discovered. The lumen output has a decrease tendency at large weight range due to the enhancement extinction coefficient, according to Mie-scattering theory. Simulation results provided important conclusions for selecting and developing the phosphor materials in MCW-LEDs manufacturing.

STUDY ON UTILIZATION OF SOYTIDE IN DIETS FOR THE PACIFIC WHITE SHRIMP, Litopenaeus vannamei

Nguyen Van Nguyen,Chang Kyung Hoon,Jun Young Bae,Seong-Jun Cho,Le Thanh Hung,Le Hoang,Tran Van Khanh 한국수산과학회 양식분과 2015 한국수산과학회 양식분과 학술대회 Vol.2015 No.5

A two-step design of experiments approach to investigate the simultaneous effects of ion-pairing and chemical enhancers to improve the permeability of lornoxicam in a topical hydrogel patch

Nguyen Huu-Manh,Duong The-Khang,Nguyen Van-Khuyen,Nguyen Thi-Khanh-Ly,Dong Thi-Hoang-Yen,Nguyen Canh-Hung,Tung Nguyen-Thach 한국약제학회 2024 Journal of Pharmaceutical Investigation Vol.54 No.2

Purpose A two-step experimental design was used to develop a lornoxicam (LOR)-loaded topical hydrogel patch. We specifically focused on the simultaneous effect of the ion pair formation agent (triethanolamine [TEA]) and the chemical enhancer (cremophor RH40 [RH40]) on flux and conducted physicochemical studies and skin physiology assessments to obtain further information. Methods Drug-in-adhesive patches were fabricated using a micrometer-adjustable film applicator. The applied Design of Experiments (DoE) approach consisted of the Fractional Factorial Resolution V + design and the Central Composite Face design established by the MODDE® 12.0 software. Molecular-level drug-excipient interactions were investigated using infrared (IR) and proton nuclear magnetic resonance (1H NMR) spectroscopy. The effects on skin physiological function was assessed using DermaLab Combo. Results DoE results revealed that TEA enhanced flux by 3.14-fold, whereas RH40 reduced it by 4.62-fold. The addition of RH40 resulted in the disappearance of the proton peak within the region of 12–13 ppm, suggesting competition for hydrogen bonding with LOR between TEA and RH40. The optimized formulation (4% TEA, 0% RH40, and 0.2% Al(OH)3) increased skin hydration by 6.20-fold. Opposing effects of TEA and RH40 on skin elasticity were observed. Conclusion Expected flux and adhesion strength for the optimized formulation were 7.18 μg·cm–2·h–1 and 11.79 mJ, respectively. Our understanding of the conflicting effects of TEA and RH40 has been advanced. The integrated use of the two-step DoE, physicochemical studies, and skin physiology assessments was proven to be effective in elucidating the simultaneous effects of different permeation-modifying strategies on patches, thus having substantial value for the successful execution of future research endeavors.

Advanced Magnetic Materials Produced by Using Rapid Quenching Technology

Nguyen Hoang Nghi,Nguyen Van Dung,Trinh Thi Thanh Nga,Bui Thi Khanh Nhung,Mai Thanh Tung,Nguyen Huu Tinh,Hoang Nhat Hieu,Bui Xuan Chien,Nguyen Thi Hong Tam 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.6

Amorphous alloys produced by using a rapid quenching technique are considered to be a precursor for producing nanosized and multiphase structures by precipitation (the top-down method). By using this technique, several new magnetic materials with different magnetic properties based on different physical mechanisms have been manufactured and investigated. Three new magnetic materials, a nanocrystalline soft magnetic material, a soft-hard permanent magnet and a Me-3d granular alloy with a GMR effect, what were prepared under local conditions, are presented and discussed in the experimental point of view. Amorphous alloys produced by using a rapid quenching technique are considered to be a precursor for producing nanosized and multiphase structures by precipitation (the top-down method). By using this technique, several new magnetic materials with different magnetic properties based on different physical mechanisms have been manufactured and investigated. Three new magnetic materials, a nanocrystalline soft magnetic material, a soft-hard permanent magnet and a Me-3d granular alloy with a GMR effect, what were prepared under local conditions, are presented and discussed in the experimental point of view.

X-ray absorption spectroscopies of Mg-Al-Ni hydrotalcite like compound for explaining the generation of surface acid sites

Hong Khanh Dieu Nguyen,Toan Dang Nguyen,Dung Ngoc Hoang,Duc Sy Dao,Thao Tien Nguyen,Limphirat Wanwisa,Lan Linh Hoang 한국화학공학회 2017 Korean Journal of Chemical Engineering Vol.34 No.2

Hydrotalcite-like compound containing metal cations such as Mg2+, Al3+ and Ni2+ was characterized using Ni K-edge EXAFS and in situ Ni K-edge XANES techniques for clarifying its bonding environment around Ni2+ sites and structure changes during calcination from room temperature to 550 oC, respectively. At the fixed molar ratio of Mg/Ni/Al of 2/1/1, the results obtained from EXAFS analysis showed a slight blue shift before and after the calcination at 550 oC and a reduction in white line peak; the best fits of the two samples revealed tiny change in coordination number about 7 for Ni-O path but considerable difference for Ni-Mg(Al) path from about 4.5 to 9.5, confirming a modification from brucite like to mixed oxide structure. On the other hand, bond distances of the Ni-O and Ni-Mg paths nearly fixed at about 2.06 Å to 3.0 Å reflected stability of the cationic bond order on each plane, but partial collapse and decomposition of the interlayer formed by water molecules and anion CO3 2− after the calcination. Linear combination fit extracted from the in situ Ni K-edge XANES also confirmed the changes along with the calcination such as slow and fast decreases of brucite fraction at 150 oC and 330 oC, respectively, in corresponding to the mixed oxide fraction increases. The achieved bonding structures were also applied to explain acid-base occurrence of the hydrotalcite-like material, especially the acid sites generated by different static charges along with the bonds. The explanation was illustrated by NH3-TPD method.

Identification of three novel mutations in PCNT in vietnamese patients with microcephalic osteodysplastic primordial dwarfism type II

Thu Hien Nguyen,Ngoc‑Lan Nguyen,Chi Dung Vu,Can Thi Bich Ngoc,Ngoc Khanh Nguyen,Huy Hoang Nguyen 한국유전학회 2021 Genes & Genomics Vol.43 No.2

Background Primordial dwarfsm (PD) is a group of genetically heterogeneous disorders related to developmental disabilities occurring in the uterus and prolongs during all stages of life, resulting in short stature, facial deformities and abnormal brain. Objective To determine the exact cause of the disease in two Vietnamese patients priory diagnosed with PD by severe preand postnatal growth retardation with marked microcephaly and some bone abnormalities. Methods Whole-exome sequencing was performed for the two patients and mutations in genes related to PD were screened. Sanger sequencing was applied to examine the mutations in the patients of their families. Results Three novel mutations in the PCNT gene which have not been reported previously were identifed in the two patients. Of which, two frameshift mutations (p.Thr479Profs*6 and p.Glu2742Alafs*8) were detected in patient I and one stop-gained mutation (p.Gln1907*) was detected in the patient II. These mutations may result in a truncated PCNT protein, leading to an inactivated PACT domain corresponding to residue His3138–Trp3216 of PCNT protein. Therefore, the three mutations may cause a defciency of protein functional activity and result in the phenotypes of primordial dwarfsm in the two patients. Conclusions Clinical presentations in combination with genetic analyses supported an accurate diagnosis of the two patients with microcephalic osteodysplastic primordial dwarfsm type II (MOPD II). In addition, these results have important implications for prenatal genetic screening and genetic counseling for the families.

Effect of Saline Concentrations on Biological Nitrification in Batch Reactor

Young Joon Lee, Nguyen Viet Hoang, Nguyen Hong Khanh, Pham Tuan Linh, Gi Youn Kim 조선대학교 기초과학연구원 2011 조선자연과학논문집 Vol.4 No.2

Pham Tuan Linh2 and Gi Youn Kim This study was carried out on 4 batch reactors to determine the specific ammonium oxidizing rate (SAOR), specific nitrate forming rate (SNFR) and inhibitory degree of nitrifying activities with saline concentrations. Under salt free condition ammonia was consumed during the reaction period within 200 min. When the salt level increased to 10, 20 and 30 g NaClL-1 in reactor, ammonia depletion took 250, 300 and above 350 min, respectively. During concentration above 10 g NaClL-1, there was nitrite accumulation. Also, at 30 g NaClL-1 ammonia did not depleted and NO2 --N accumulated until the final reaction. Nitrate formation rates decreased with increasing salt concentration. SAOR and SNFR showed a decreasing trend as salinity concentrations were increased. The SAOR was reduced from 0.2 to 0.08 mg NH4+-N g-1VSS day-1 as the salt concentration increased from 0 to 30 g NaCLL-1. Similarly, the SNFR decreased from 0.26 kg NO3--N kg-1VSS day-1 at saline free to 0.1 kg NO3--N kg-1VSS day-1 at saline 30 g L-1. A severe inhibition of nitrifiers activity was observed at increased salt concentrations. The inhibition ratio of specific ammonium oxidation rates were 17, 47 and 60% on the reactor of 10, 20 and 30 g NaClL-1 added, respectively. The inhibition ratio of specific nitrate forming rates also were inhibited 30, 53 and 62% on the reactor of 10, 20 and 30 g NaClL-1 added, respectively. As the salinity concentrations increased from 0 to 30 mg NaClL-1, the average MLSS concentration increased from 1,245 to 1,735 mgL-1. The SS concentration of supernatant in reactor which settled about 30 minutes was not severely difference between concentration of salt free reactor and one of those high salt contained reactors