Enhancement of artemisinin content by constitutive expression of the HMG-CoA reductase gene in high-yielding strain of Artemisia annua L.

Nafis, Tazyeen,Akmal, Mohd.,Ram, Mauji,Alam, Pravej,Ahlawat, Seema,Mohd, Anis,Abdin, Malik Zainul The Korean Society of Plant Biotechnology 2011 Plant biotechnology reports Vol.5 No.1

Artemisinin is effective against both chloroquine-resistant and -sensitive strains of Plasmodium species. However, the low yield of artemisinin from cultivated and wild plants is a serious limitation to the commercialization of this drug. Optimization of artemisinin yield either in vivo or in vitro is therefore highly desirable. To this end, we have overexpressed the 3-hydroxy-3-methyl-glutaryl-coenzyme A reductase (HMGR) gene (hmgr) from Catharanthus roseus L. in Artemisia annua L. and analyzed its influence on artemisinin content. PCR and Southern blot analyses revealed that the transgenic plants showed stable integration of the foreign hmgr gene. The reverse transcriptase-PCR results suggested that the hmgr was expressed at the transcriptional level in transgenic lines of Artemisia annua L., while the high-performance liquid chromatography analysis showed that artemisinin content was significantly increased in a number of the transgenic lines. Artemisinin content in one of the A. annua transgenic lines was 38.9% higher than that in non-transgenic plants, and HMGR enzyme activity in transgenic A. annua L. was also higher than that in the non-transgenic lines.

3D Path Planning of Unmanned Aerial Vehicles

Nafis Ahmed,Umair Ahmad Mughal,KyungHi Chang 한국통신학회 2020 한국통신학회 학술대회논문집 Vol.2020 No.2

Utilization of Oil Palm Decanter Cake for Cellulase and Polyoses Production

Mohamad Nafis Abdul Razak,Mohamad Faizal Ibrahim,Phang Lai Yee,Mohd Ali Hassan,Suraini Abd-Aziz 한국생물공학회 2012 Biotechnology and Bioprocess Engineering Vol.17 No.3

The abundance of oil palm decanter cake (OPDC) is a problem in oil palm mills. However, this lignocellulosic biomass can be utilized for cellulase and polyoses production. The effectiveness of chemical and physical pretreatment in reducing the lignin content was studied by saccharification using a Celluclast 1.5 L and scanning electron microscope. Physicochemical pretreatment of OPDC with 1% (w/v) NaOH and autoclaving at 121oC for 20 min increased potential polyoses produced to 52.5%and removed 28.7% of the lignin content. The optimized conditions for cellulase production by a locally isolated fungus were a time of 120 h, a substrate of untreated OPDC,a spore concentration of 1 × 107 spore/mL, a temperature of 30oC, and a pH between 7.0 and 7.5. Trichoderma asperellum UPM1 produced carboxymethylcellulase (CMCase),β-glucosidase and filter paper activity (FPase) in the following concentrations: 17.35, 0.53, and 0.28 U/mL,respectively. Aspergillus fumigatus UPM2 produced the CMCase, β-glucosidase and FPase in the following amounts: 10.93, 0.76, and 0.24 U/mL. The cellulases from T. asperellum UPM1 produced 2.33 g/L of polyoses and the cellulases from A. fumigatus UPM2 produced 4.37 g/L of polyoses.

Influence of hard rock dust on the physical and microstructural properties of red ceramic materials

Ahmed Aninda Nafis,Sultana Mst. Shanjida,Zaman Mohammad Nazim,Rahman Md. Aminur 한국세라믹학회 2021 한국세라믹학회지 Vol.58 No.1

Rock dust disposal is a concern in a hard rock mining site which results from blasting operation during mining. Signifi cant amount of rock dust is generated during mining which causes dusting problem as well. In this work, Rock dust was used with red clay to produce ceramic tiles. XRF analysis revealed the existence of more than 60 wt.% SiO 2 in red clay and more than 50 wt.% SiO 2 in rock dust. Pressed ceramic bodies having diff erent amount (10–30 wt.%) of rock dust were sintered at 1050 °C, 1100 °C and 1150 °C. Diff erent properties were measured for ceramics samples such as water absorption, porosity, mechanical strength, linear shrinkage and bulk density. Lowering of porosity (1.88–10.17%) and water absorption (1.1–6.03%) were found with 10–30 wt.% rock dust addition. Above 50 MPa of compressive strength was found, which is satisfactory for producing ceramic tiles. Microstructures of ceramics samples studied by FESEM provided eff ective information on structure-property relationships. Maximum quantities of rock dust waste were utilized, in reducing environmental pollution and establishing it as a raw material for ceramics industries.

An Application of TAM and TRI on the Factors Affecting Internet Banking Adoption in Bangladesh

Md. Iftekharul AMIN(Md. Iftekharul AMIN ),Nafis ERFAN(Nafis ERFAN ),Mashrur NAVID(Mashrur NAVID ),Mohammed Shafiul Alam KHAN(Mohammed Shafiul Alam KHAN ),Md. Shariful ISLAM(Md. Shariful ISLAM ) 한국유통과학회 2022 The Journal of Asian Finance, Economics and Busine Vol.9 No.9

This study assesses the Internet banking adoption tendency by existing bank customers of Bangladesh. Currently, almost all the leading banks in the country have implemented Internet banking platforms. However, the active user count remains relatively low and there hasn’t been any conclusive research on the drivers and inhibitors of Internet banking. This study evaluates the reasons and quantitatively establishes the factors leading to the adoption and usage continuance of internet banking by existing bank customers. Responses from 460 bank account holders were collected via online questionnaires using a purposive sampling approach, and a core conceptual framework based on Technology Acceptance Model (TAM) and Technology Readiness Index (TRI) was used. The study concluded that internet banking adoption is significantly impacted by the ease of use, customer service, and technology familiarity. Similarly, customer satisfaction is affected by the perceived value and the perceived risk. Through regression analysis, it was found that usage continuance is 89% explained by adoption and customer satisfaction. Multi-group moderation showed significant impact by groups divided based on usage frequency, income level, and age. Perceived risk weakened the impact of perceived value and technology familiarity on usage adoption. Additionally, perceived risk reduced the impact of consumer satisfaction and usage continuance.

Feasibility Analysis of AI Algorithms for MCS Selection in Wireless Communication Systems

Najnin Sultana,Nafis Ahmed,Azharul Islam,KyungHi Chang 한국통신학회 2020 한국통신학회 학술대회논문집 Vol.2020 No.2

Correlation Between Reflectance and Photoluminescent Properties of Al-rich ZnO Nano-Structures

Firoz Khan,백성호,Nafis Ahmad,이건희,서태훈,서은경,김재현 대한금속·재료학회 2015 METALS AND MATERIALS International Vol.21 No.3

Al rich zinc oxide nano-structured films were synthesized using spin coating sol-gel technique. The films were annealed in oxygen ambient in the temperature range of 200-700 °C. The structural, optical, and photoluminescence (PL) properties of the films were studied at various annealing temperatures using X-ray diffraction spectroscopy, field emission scanning electron microscopy, photoluminescence emission spectra measurement, and Raman and UV-Vis spectroscopy. The optical band gap was found to decrease with the increase of the annealing temperature following the Gauss Amp function due to the confinement of the exciton. The PL peak intensity in the near band region (INBE) was found to increase with the increase of the annealing temperature up to 600 °C, then to decrease fast to a lower value for the annealing temperature of 700 °C due to crystalline quality. The Raman peak of E2 (low) was red shifted from 118 cm-1 to 126 cm-1 with the increase of the annealing temperature. The intensity of the second order phonon (TA+LO) at 674 cm-1 was found to decrease with the increase of the annealing temperature. The normalized values of the reflectance and the PL intensity in the NBE region were highest for the annealing temperature of 600 °C. A special correlation was found between the reflectance at λ = 1000 nm and the normalized PL intensity in the green region due to scattering due to presence of grains.

Transonic Speed Mobility Support Techniques for 6G-Non Terrestrial Networks

Chaitali J. Pawase,Nafis Ahmed,KyungHi Chang 한국통신학회 2021 한국통신학회 학술대회논문집 Vol.2021 No.6

Non-Terrestrial Network (NTN) connectivity is expected to be used in sixth Generation (6G) telecommunication systems to support transonic speed mobility applications. NTN systems can provide wide-area coverage for applications that require high mobility. Third Generation Partnership Project (3GPP) is investigating a study on New Radio (NR) and solutions for NR to support NTN in Release-15 and Release-16 respectively. In this paper, we provide an overview of use cases, requirements and architecture of a non-terrestrial network and explain high mobility such as transonic speed mobility challenges and potential solutions to be resolved in 6G-NTN. In addition, we also describe the existing open research opportunities for non-terrestrial network implementation based on 5G-NR in order to encourage extensive research in 6G technology.

An Immunohistochemical and Polarizing Microscopic Study of the Tumor Microenvironment in Varying Grades of Oral Squamous Cell Carcinoma

Aeman Khalid,Safia Siddiqui,Bharadwaj Bordoloi,Nafis Faizi,Fahad Samadi,Noora Saeed 대한병리학회 2018 Journal of Pathology and Translational Medicine Vol.52 No.5

Background: Invasion of epithelial cells into the connective tissue brings about massive morphological and architectural changes in the underlying stroma. Myofibroblasts reorganize the stroma to facilitate the movement of tumor cells leading to metastasis. The aim of this study was to determine the number and pattern of distribution of myofibroblasts and the qualitative and quantitative change that they cause in the collagen present in the stroma in various grades of oral squamous cell carcinoma (OSCC). Methods: The study was divided into two groups with group I (test group, 65 cases) consisting of 29 cases of well-differentiated squamous cell carcinoma, 25 moderately differentiated SCC, and 11 poorly differentiated SCC, and group II (control group) consisting of 11 cases of normal mucosa. Sections from each sample were stained with anti–α-smooth muscle actin (α-SMA) antibodies, hematoxylin and eosin, and Picrosirius red. Several additional sections from each grade of OSCC were stained with Masson’s trichrome to observe the changes in collagen. For the statistical analysis, Fisher’s exact test, Tukey’s post hoc honest significant difference test, ANOVA, and the chi-square test were used, and p < .05 was considered statistically significant. Results: As the tumor stage progressed, an increase in the intensity α-SMA expression was seen, and the network pattern dominated in more dedifferentiated carcinomas. The collagen fibers became thin, loosely packed, and haphazardly aligned with progressing cancer. Additionally, the mean area fraction decreased, and the fibers attained a greenish yellow hue and a weak birefringence when observed using polarizing light microscopy. Conclusions: Myofibroblasts bring about numerous changes in collagen. As cancer progresses, there isincrease in pathological collagen,which enhances the movement of cells within the stroma.

Influence of Sn Doping on the Structural, Morphological, Optical and Photocatalytic Functionality of ZnO Nanostructures

K. Ganesh Kumar,P. Balaji Bhargav,Nafis Ahmed,C. Balaji 한국전기전자재료학회 2021 Transactions on Electrical and Electronic Material Vol.22 No.6

In the present study, pure and Tin (Sn) doped ZnO (Sn–ZnO) nanostructures are grown using hydrothermal method. The effect of Sn doping on the physical properties of ZnO is extensively studied. Till 4 mol% of Sn doping, the dopant is completely dissolved in the host matrix and no secondary phases are formed as evident from XRD studies. The presence of the constituent elements of the host matrix (Zn,O) and dopant (Sn) is confi rmed using Energy Dispersive X-ray Spectroscopy (EDX). From FESEM images, it is evident that the morphology of the grown structures changes from rods to flowers and flakes with doping. The microstructural analysis is carried out using HRTEM analysis. Various polar and non-polar optical modes present in the samples are analysed using Raman spectra. Two dominant emission bands around ~391 nm, ~470 nm are noticed from photoluminescence (PL) spectra. The potential of the Sn doped ZnO nanostructures in photocatalytic degradation of Rhodamine B is investigated and found that 1 mol% Sn doped ZnO exhibits superior photo catalytic performance.