http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Azad, M. Abul Kalam,Alam, M. Shamsul,Rahman, M. Saifur,Sarker, Bimolendu Shekhar Korean Mathematical Society 2011 대한수학회논문집 Vol.26 No.4
Based on the multiple-time-scale (MTS) method, a general formula has been presented for solving an n-th, n = 2, 3, ${\ldots}$, order ordinary differential equation with strong linear damping forces. Like the solution of the unified Krylov-Bogoliubov-Mitropolskii (KBM) method or the general Struble's method, the new solution covers the un-damped, under-damped and over-damped cases. The solutions are identical to those obtained by the unified KBM method and the general Struble's method. The technique is a new form of the classical MTS method. The formulation as well as the determination of the solution from the derived formula is very simple. The method is illustrated by several examples. The general MTS solution reduces to its classical form when the real parts of eigen-values of the unperturbed equation vanish.
( Abul Kalam Azad ),( Asraful Jahan ),( Mahbub Hasan ),( Takahiro Ishikawa ),( Yoshihiro Sawa ),( Hitoshi Shibata ) 생화학분자생물학회 2011 BMB Reports Vol.44 No.11
The Sec61α subunit is the core subunit of the protein conducting channel which is required for protein translocation in eukaryotes and prokaryotes. In this study, we cloned a Sec61α subunit from Penicillium ochrochloron (PoSec61α). Sequence and 3D structural model analysis showed that PoSec61α conserved the typical characteristics of eukaryotic and prokaryotic Sec61α subunit homologues. The pore ring known as the constriction point of the channel is formed by seven hydrophobic amino acids. Two methionine residues from transmembrane α-helice 7 (TM7) contribute to the pore ring formation and projected notably to the pore area and narrowed the pore compared with the superposed residues at the corresponding positions in the crystal structures or the 3D models of the Sec61α subunit homologues in archaea or other eukaryotes, respectively. Results reported herein indicate that the pore ring residues differ among Sec61α subunit homologues and two hydrophobic residues in the TM7 contribute to the pore ring formation. [BMB reports 2011; 44(11): 719-724]
Abul Kalam Azad,Wan Mohd Azizi Wan Sulaiman,Sukalyan Kumar Kundu 경희대학교 융합한의과학연구소 2022 Oriental Pharmacy and Experimental Medicine Vol.22 No.3
The fruits of Phaleria macrocarpa (PM) have long been used as a traditional Malay medicinal herb for hundreds of years. To determine the toxicity of the mesocarp and pericarp of ethanol extract of PM (EEPM). In this study, 6–8 weeks of adult healthy male Sprague-Dawley (SD) rats between 180 and 220 g, were used. The Group I was received 10 % normal saline and Group II, III, IV and V were treated with EEPM orally to each rat (n = 6) on daily basis at 500, 1000, 2000 and 5000 mg/ kg 28 consecutive days. Animals body weight showed normal growth from 189.76 ± 2.33 and 189.86 ± 1.01 g to 227 ± 3.06 and 225 ± 2.07 g. Biochemical aspects of treated animals’ indicated serum values of (creatinine 0.46 ± 0.033, phosphorous 5 ± 0.46, HDL 31.31 ± 1.48, LDL 30.66 ± 0.37, Cholesterol 68.23 ± 1.28 and AST 63.08 ± 2.65, ALT 22.05 ± 0.68 and ALP 79.16 ± 0.82) which is similar with the control group. Histological observation showed no necrosis, abnormalities and inflammation in both control and EEPM treated groups. Findings suggests; the fruits are non-toxic when applied to SD rats. In this way, it may also serve as a good alternative in the present armamentarium of traditional medicine without showing its any side effects.
Azad, Md. Abul Kalam,Sawa, Yoshihiro,Ishikawa, Takahiro,Shibata, Hitoshi Korean Society for Biochemistry and Molecular Biol 2006 Journal of biochemistry and molecular biology Vol.39 No.6
The holoenzyme of protein phosphatase (PP) from tulip petals was purified by using hydrophobic interaction, anion exchange and microcystin affinity chromatography to analyze activity towards p-nitrophenyl phosphate (p-NPP). The catalytic subunit of PP was released from its endogenous regulatory subunits by ethanol precipitation and further purified. Both preparations were characterized by immunological and biochemical approaches to be PP2A. On SDS-PAGE, the final purified holoenzyme preparation showed three protein bands estimated at 38, 65, and 75 kDa while the free catalytic subunit preparation showed only the 38 kDa protein. In both preparations, the 38 kDa protein was identified immunologically as the catalytic subunit of PP2A by using a monoclonal antibody against the PP2A catalytic subunit. The final 623- and 748-fold purified holoenzyme and the free catalytic preparations, respectively, exhibited high sensitivity to inhibition by 1 nM okadaic acid when activity was measured with p-NPP. The holoenzyme displayed higher stimulation in the presence of ammonium sulfate than the free catalytic subunit did by protamine, thereby suggesting different enzymatic behaviors.
Identification of a Novel Sugar Compound from Korean Pine Seeds
Md. Abul Kalam Azad,Fei Wang,김학렬 한국식품과학회 2015 Food Science and Biotechnology Vol.24 No.6
Sugar derivatives are critically important in nutritional, pharmaceutical, and some non-food industries. Amino sugars are more important as essential components of many drugs, antibiotics, and biopolymers. Hence, a novel amino sugar compound is worthy of investigation for identification and production. A novel amino sugar compound was identified from crude extracts of Korean pine seed embryos. This new compound was isolated from extracts using traditional purification steps. The pure compound was white in color with a melting point of 145℃. HPLC, TLC, FT-IR, and NMR analyses of the compound indicated a trisaccharide form of amino mannose that was polymerized with β-(1→2) glycosidic bonding. Computer-aided NMR spectral analysis of the trisaccharide of 2-dehydro-2- mannosamine exhibited a 96% match with the 13C-NMR spectrum of the new compound.
Residual Strength of Corroded Reinforced Concrete Beams Using an Adaptive Model Based on ANN
Ashhad Imam,Fatai Anifowose,Abul Kalam Azad 한국콘크리트학회 2015 International Journal of Concrete Structures and M Vol.9 No.2
Estimation of the residual strength of corroded reinforced concrete beams has been studied from experimental and theoretical perspectives. The former is arduous as it involves casting beams of various sizes, which are then subjected to various degrees of corrosion damage. The latter are static; hence cannot be generalized as new coefficients need to be re-generated for new cases. This calls for dynamic models that are adaptive to new cases and offer efficient generalization capability. Computational intelligence techniques have been applied in Construction Engineering modeling problems. However, these techniques have not been adequately applied to the problem addressed in this paper. This study extends the empirical model proposed by Azad et al. (Mag Concr Res 62(6):405?414, 2010), which considered all the adverse effects of corrosion on steel. We proposed four artificial neural networks (ANN) models to predict the residual flexural strength of corroded RC beams using the same data from Azad et al. (2010). We employed two modes of prediction: through the correction factor (Cf) and through the residual strength (Mres). For each mode, we studied the effect of fixed and random data stratification on the performance of the models. The results of the ANN models were found to be in good agreement with experimental values. When compared with the results of Azad et al. (2010), the ANN model with randomized data stratification gave a Cf-based prediction with up to 49 % improvement in correlation coefficient and 92 % error reduction. This confirms the reliability of ANN over the empirical models.