Authors:M. Moniruzzaman, S. B. Faruque Pages: 99 - 103 Abstract: We find the shift of ground state energy of deuteron caused by generalized uncertainty principle (GUP) using Yukawa potential as the binding force between the proton and neutron. This leads to an upperbound on minimal length of about 10 -18 m which is close to the values frequently found in literature. PubDate: 2018-05-01 DOI: 10.3329/jsr.v10i2.32829 Issue No:Vol. 10, No. 2 (2018)
Authors:A. H. Farazi, N. Ferdous, A. S. M. M. Kamal Pages: 105 - 116 Abstract: This study aims at evaluation of seismic soil liquefaction hazard potential at Probashi Palli Abasan Project area of Tongi, Gazipur, exploiting standard penetration test (SPT) data of 15 boreholes, following Simplified Procedure. Liquefaction potential index (LPI) of each borehole was determined and then cumulative frequency distribution of clustered LPI values of each surface geology unit was determined assuming cumulative frequency at LPI = 5 as the threshold value for liquefaction initiation. By means of geotechnical investigation two surface geological units—Holocene flood plain deposits, and Pleistocene terrace deposits were identified in the study area. We predicted that 14% and 24% area of zones topped by Pleistocene terrace deposits and zones topped by Holocene flood plain deposits, respectively, would exhibit surface manifestation of liquefaction as a result of 7 magnitude earthquake. The engendered hazard map also depicts site specific liquefaction intensity through LPI values of respective boreholes, and color index, which was delineated by mapping with ArcGIS software. Very low to low, and low to high liquefaction potential, respectively, was found in the areas covered by Pleistocene terrace deposits and Holocene flood plain deposits. LPI values of both units are such that sand boils could be generated where LPI > 5.
Authors:D. Deb, M. A. Uddin, H. Terashima, N. Oshima Pages: 117 - 131 Abstract: A knocking combustion in a one-dimensional constant volume reactor has been simulated with a detailed chemical kinetic mechanism of n-heptane premixed gases by using the compressible Navier-Stokes equations. This study focuses on the impact of the various equivalence ratios (0.6–1.4) in the pressure wave development during knocking combustion in an account of different initial temperature (600–900K). The result demonstrates the autoignition process in the end-gas region and explains the knocking phenomenon on different equivalence ratio. In an adiabatic wall condition, the largest knocking intensity occurs in equivalence ratio 1.4 whereas the lowest knocking intensity found in equivalence ratio 0.6. Regarding to initial temperatures, a strong peak of knocking is generated around 650K in all the equivalence ratios (0.8–1.4). However, yet a small perceptivity of knocking is found in around 750K for each equivalence ratio. In case of smaller equivalence ratios, a weak knocking occurs, which can be identified by the behavior of the pressure wave generation in the end-gas region. PubDate: 2018-05-01 DOI: 10.3329/jsr.v10i2.34491 Issue No:Vol. 10, No. 2 (2018)
Authors:S. Bhardwaj, P. A. Khan, R. Atulkar, P. K. Purohit Pages: 133 - 144 Abstract: The fluctuations in the Interplanetary Magnetic Field significantly affect the state of geomagnetic field particularly during the Coronal Mass Ejection (CME) events. In the present investigation we have studied the influence of Interplanetary Magnetic Field changes on the geomagnetic field components at high, low and mid latitudes. To carry out this investigation we have selected three stations viz. Alibag (18.6°N, 72.7°E), Beijing MT (40.3°N, 116.2°E) and Casey (66.2°S, 110.5°E) one each in the low, mid and high latitude regions. Then we selected geomagnetic storm events of three types namely weak (-50≤Dst≤-20), moderate (100≤Dst≤-50) and intense (Dst≤-100nT). In each storm category 10 events were considered. From our study we conclude that geomagnetic field components are significantly affected by the changes in the IMF at all the three latitudinal regions during all the storm events. At the same time we also found that the magnitude of change in geomagnetic field components is highest at the high latitudes during all types of storm events while at low and mid latitude stations the magnitude of effect is approximately the same. PubDate: 2018-05-01 DOI: 10.3329/jsr.v10i2.34509 Issue No:Vol. 10, No. 2 (2018)
Authors:R. Shanker, K. K. Shukla Pages: 145 - 157 Abstract: In this paper, generalized size-biased Poisson-Lindley distribution (GSBPLD) which includes size-biased Poisson-Lindley distribution (SBPLD) as particular case, has been proposed and studied. Its moments based measures including coefficients of variation, skewness, kurtosis, and index of dispersion have been derived and their nature and behavior have been discussed with varying values of the parameters. The estimation of its parameter has been discussed using maximum likelihood estimation. Some applications of the proposed distribution have been explained through datasets relating to size distribution of freely-forming and the goodness of fit has been found satisfactory over SBPLD and size-biased Poisson distribution (SBPD). PubDate: 2018-05-01 DOI: 10.3329/jsr.v10i2.34905 Issue No:Vol. 10, No. 2 (2018)
Authors:Z. Hasan, M. S. Hossain Pages: 159 - 173 Abstract: This study mainly focused on developing skills on different field of perspective like software-based skills and interpersonal skills which will help an individual to become more proactive and efficient in their desired job field. In this memorizing based educational system students are not encouraged to learn new skills like software-based skills and interpersonal skills which are very much important to become expert and qualified individual in the corporate and competitive job field. The aim was to develop an effective method which will help the students to learn these necessary skills besides their regular course related study. It was focused on using this method by approaching on a gradual step by step procedure and developed it to solve the problem. It will save the time of the students and also make their fundamental knowledge strong on different software. A survey was conducted among the students from own university and got a satisfactory response from them. Most of them were looking for an effective process of learning without harming regular studies. This method will obviously help the students of our country to improve skills besides regular studies in a more effective way to be expert in their own field of specialization. PubDate: 2018-05-01 DOI: 10.3329/jsr.v10i2.35638 Issue No:Vol. 10, No. 2 (2018)
Authors:A. K. Azad, M. A. Jainul, Z. K. Labu Pages: 175 - 185 Abstract: The aim of our study was to find out the preliminary cytotoxic and thrombolytic effect of the seven selected medicinal plant leaves extract. In cytotoxic activity, out of the seven leaves extract three of them exhibited stronger brine shrimp lethality with LC50 122.548 (Uncaria acida), 170.861 (Leea indica) and 175.469 (Piper porphyrophyllum) μg /mL respectively, and on MCF-7 cell line, they also exhibited moderate cytotoxic activity with different concentration of the extract of the same plant leaves such as,Uncaria acida (72.31, 56.22, 38.12 and 9.24%), Leea indica (67.31, 58.22, 43.12 and 15.24%), Piper porphyrophyllum (65.88, 48.12, 40.12 and 21.34%). In thrombolytic assessments, all the leaves extract showed moderate (considering > 20% moderate; **p < 0.01; *p < 0.05) clot lysis activity, but among the extracts, Uncaria cordata (27.36 ± 0.10%) showed the highest and Stachytarpheta indica the lowest (6.14 ± 0.20%) percent clot lysis as compared with the standard streptokinase (65.15 ± 0.16%). This study was conducted to legalize the folkloric use of seven medicinal plant leaves. PubDate: 2018-05-01 DOI: 10.3329/jsr.v10i2.34820 Issue No:Vol. 10, No. 2 (2018)
Authors:S. Sawadogo, S. D. Sanou, A. P. Dabiré, G. R. Belemtougri, L. Sawadogo, J. de Leiris, S. Tanguy, F. Boucher Pages: 187 - 193 Abstract: Jatropha curcas is a medicinal plant whose dead leaves are particularly used in arterial hypertension and diabetes treatment. The purpose of this study is to conduct an acute and subacute toxicity study of Jatropha curcas leaves aqueous extract (JCLAE) using OECD method. For acute toxicity, dose limits of 2000 and 5000 mg/kg were used. In subacute toxicity study 4 batches were constituted including a control batch that received distilled water for 28 days and the other 3 batches, JCLAE doses of respectively 200, 400, 800 mg/kg for the same duration. The LD50 was determined and the hematological, biochemical and histological parameters were analyzed in mice. The LD50 is greater than 5000 mg/kg. HDL-C is the only biochemical parameter that has experienced significant rise variation. Hematological analysis showed a decrease in mean platelet volume and Platelets number. The histological study revealed cases of hepatic cellular apoptosis and kidneys tubular necrosis among animals treated with highest dose. JCLAE is less toxic than Jatropha curcas leaves aqueous extract and high-dose JCLAE also has a moderate toxic effect on thrombocyte line and a protective effect on cardiovascular system. PubDate: 2018-05-01 DOI: 10.3329/jsr.v10i2.35267 Issue No:Vol. 10, No. 2 (2018)
Authors:M. Shahriar, M. A. Bhuiyan, M. S. Rana Pages: 195 - 210 Abstract: The methanol, ethanol and chlorofom leaf extracts of Satkara, Citrus assamensis (family: Rutaceae), were subjected to in vitro anti-bacterial, thrombolytic, membrane stabilizing and in vivo anti-inflammatory and antitumor activity tests. The chloroform extract of C. assamensis showed the most important spectrum of activity against Bacillus subtilis, Bacillus cereus, Sarcina lutea among 6 gram positive and against 11 gram negative bacteria at the concentration of 1000 μg/disc, while the range of zones of inhibition were within 7-16 mm. Among the tested three extracts CHCl3 extract showed potent thrombolytic activity and hypotonic solution induced haemolytic activity where the percentages of inhibition were found to be 35% and 55% respectively. All the extracts established significant (p<0.05) anti-inflammatory effect by regulating biphasic inflammatory process induced by carrageenan. The leaf extract dose-dependently and significantly decreases the number of EAC cell count and inhibition of cell growth in comparison to the EAC control and standard. The results obtained in the present study indicate that, C. assamensis leaf can be a potential source of anti-bacterial, thrombolytic, membrane stabilizing, anti-inflammatory and antitumor agents. PubDate: 2018-05-01 DOI: 10.3329/jsr.v10i2.35410 Issue No:Vol. 10, No. 2 (2018)
Authors:S. M. A. Sayem, A. J. M. T. Chowdhury, M. Z. Alam, P. K. Sarker Pages: 211 - 221 Abstract: Antibiofilm phenomenon has become a novel area of research for removing deleterious biofilm. In the present study, strains from different environmental sources were tested for screening antibiofilm compounds. Crude extracts from various microorganisms were evaluated for antibiofilm phenomenon through crystal violet assay and growth curve analysis. Characterization of antibiofilm compound was performed by pre-coating microtiter plate and Cell Surface Hydrophobicity experiment. Among the organisms, cell free extracts (5% v/v) from Bacillus subtilis S01 inhibited the development of E. coli PHL628 biofilm by 63%. The cell free extracts possessed no amylase activity and had no effect on the planktonic growth of biofilm forming bacteria. Moreover, no competition with quorum sensing analogues was found with the extract. Biofilm formation was more inhibited (76%) in the B. subtilis S01 extract pre-coated wells than uncoated wells (62%). However, no effect on preformed biofilm was observed with the extracts of B. subtilis S01. The extract also reduced the cell surface hydrophobicity (69%) of the biofilm forming bacteria. The present study indicated that the crude extracts of B. subtilis S01 from soil origin has anti-adherence properties towards biotic and abiotic surfaces and thus can be a potential candidate in preventing the development of biofilm. PubDate: 2018-05-01 DOI: 10.3329/jsr.v10i2.35604 Issue No:Vol. 10, No. 2 (2018)
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