Evaluation of heavy metal pollution risk associated with road sediment

Kazi Kader Newaz,Sudip Kumar Pal,Shahadat Hossain,Ahasanul Karim 대한환경공학회 2021 Environmental Engineering Research Vol.26 No.3

A detailed investigation has been conducted to assess the heavy metal pollution risk associated with the road deposited sediment collected from the 32 major road sites in Chittagong city. The acid digestion of road sediments for metals extraction was carried out prior to determine total concentrations of Zn, Pb, Cr, Cu, Ni, Cd by using Polarized Zeeman Atomic Absorption Spectrophotometer (Z-2000) following standard analytical protocol. The contamination and pollution risk level were assessed using degree of contamination, potential ecological risk index and integrated pollution index. The study revealed that the mean heavy metal concentrations of Zn, Pb, Cr, Cu, Ni, Cd were found as 975, 84, 77, 74, 32, 1.6 ㎎/㎏, respectively, across the road sites in Chittagong city. The mean concentrations are found 1.1 to 44 times higher in comparison to soil background, signifying relatively greater enrichment for Zn, Cd and Pb across the sites, suggesting vehicular emission on roads with site-specific characteristics. Based on pollution indices, Ruby Cement, City Gate and Enayeth Bazar road sites pose high risk, while eight other sites are found with moderate to considerable risk potential, and remaining 21 sites pose low to moderate risk potential.

Population genetic structure and demographic history of the fat greenling Hexagrammos otakii

Kazi Ahsan Habib,정다금,Jung-Goo Myoung,Min Seok Kim,장요순,Jae Seol Shim,Youn-Ho Lee 한국유전학회 2011 Genes & Genomics Vol.33 No.4

Fat greenling (Hexagrammos otakii) is an important commercial fish in the Northwestern Pacific, being distributed along the coastal waters of the East/Japan Sea and the Yellow Sea. To investigate population genetic structure and demographic history of this species, one hundred and fifty five individuals were collected from five localities in the distribution range of the species and sequence variations in the mitochondrial genes COI, COIII-ND3-ND4L, and cytochrome b were examined. For all the genes in every sampling location, the nucleotide diversities were very low (0.001 ~ 0.005) although the haplotype diversities were relatively high, 0.55 ~ 0.81 for COI, 0.79 ~ 0.84 for COIII-ND3-ND4L, and 0.95 ~ 0.97 for cytochrome b. Hierarchical analysis of molecular variance (AMOVA), the conventional population statistic FST, and exact test of population differentiation revealed no significant genetic structuring among the samples, indicating that fat greening is panmictic throughout the range of its distribution. Neutrality tests such as Tajima’s D and Fu’s FS statistics and mismatch distribution analyses suggested that fat greening has undergone the demographic history of population expansion during the late Pleistocene period approximately 91,000 ~327,000 years ago. The star-burst patterns of haplotype networks and low nucleotide diversities also indicated recent population expansion. These results help establish the fisheries management strategy for fat greenling in the Northwestern Pacific.

Impact of teachers' professional development on school improvement-an analysis at Bangladesh standpoint

Kazi Enamul Hoque,Gazi Mahabubul Alam,Abdul Ghani Kanesean Abdullah 서울대학교 교육연구소 2011 Asia Pacific Education Review Vol.12 No.3

This study seeks to describe the teachers' professional development activities in Bangladesh and explores the hypotheses about the relationship between teachers' traditional professional development activities and school improvement. Data from a representative sample of City secondary schools from Bangladesh (n = 127) were gathered through questionnaires from 127 principals and 694 teachers. Hierarchical multiple regression analysis was used in this research. This study found significant impacts of some of teachers' professional development activities on school improvement. Also found that the maximum school improvement can be achieved if schools put more emphasis on teachers' collaboration, in-service training and classroom observation and less emphasis on individual action enquiry. The findings of this study provide important information for the policy makers, educational managers and especially for the headmasters and teachers concerned with the improvement of teachers' quality in secondary schools of Bangladesh. This study adopts a concurrent approach of data collection and analysis.

Role of Regulatory Domain Mutants of PKC Isoforms in c-fos Induction

Kazi, Julhash U.,Soh, Jae-Won Korean Chemical Society 2008 Bulletin of the Korean Chemical Society Vol.29 No.1

Population Panmixia and the Pleistocene Demographic Expansion of Spotty Belly Greenling Hexagrammos agrammus in the East Sea and Northwest Pacific

Kazi Ahsan Habib,정다금,명정구,이윤호 한국해양과학기술원 2015 Ocean science journal Vol.50 No.2

The population genetic structure and historical demography of spotty belly greenling, Hexagrammos agrammus, which has limited distribution in the Northwest Pacific, was assessed with partial sequences of the mitochondrial DNA (mtDNA) cytochrome b and the control region (D-loop). A total of 103 individuals were collected from four sites located at the Korea Strait (Southern coast of Korea) and the East coast of Korea and two places in the Pacific coast of Japan. For all the populations, nucleotide diversities were low (0.006 - 0.009) while the haplotype diversities were as high as 0.92 to 0.97, indicating that the fish has undergone a recent population expansion after experiencing bottleneck. Star-shaped patterns of haplotype networks as well as the significant negative values of Tajima’s D and Fu’s FS corroborate the recent population expansion. Mismatch distribution analysis reveals that the demographic expansion of the species started during the 2nd half of the Middle Pleistocene Series approximately 141,000 - 406,000 years ago. Hierarchical analysis of molecular variance (AMOVA), the pairwise population statistics (FST), and the exact test of haplotype differentiation demonstrate no significant genetic differentiation among populations investigated, suggesting that spotty belly greenling is panmictic in the East Sea and the Pacific coast of Japan.

Cytotoxicity and biocompatibility of high mol% yttria containing zirconia

Kazi Gulsan Ara Sathi,Yamagiwa Ryo 대한치과보존학회 2020 Restorative Dentistry & Endodontics Vol.45 No.4

Objectives: Yttria-stabilized tetragonal phase zirconia has been used as a dental restorative material for over a decade. While it is still the strongest and toughest ceramic, its translucency remains as a significant drawback. To overcome this, stabilizing the translucency zirconia to a significant cubic crystalline phase by increasing the yttria content to more than 8 mol% (8YTZP). However, the biocompatibility of a high amount of yttria is still an important topic that needs to be investigated. Materials and Methods: Commercially available 8YTZP plates were used. To enhance cell adhesion, proliferation, and differentiation, the surface of the 8YTZP is sequentially polished with a SiC-coated abrasive paper and surface coating with type I collagen. Fibroblast-like cells L929 used for cell adherence and cell proliferation analysis, and mouse bone marrow-derived mesenchymal stem cells (BMSC) used for cell differentiation analysis. Results: The results revealed that all samples, regardless of the surface treatment, are hydrophilic and showed a strong affinity for water. Even the cell culture results indicate that simple surface polishing and coating can affect cellular behavior by enhancing cell adhesion and proliferation. Both L929 cells and BMSC were nicely adhered to and proliferated in all conditions. Conclusions: The results demonstrate the biocompatibility of the cubic phase zirconia with 8 mol% yttria and suggest that yttria with a higher zirconia content are not toxic to the cells, support a strong adhesion of cells on their surfaces, and promote cell proliferation and differentiation. All these confirm its potential use in tissue engineering.

Mechanical Properties of Carbon Nanotubes with Randomly Distributed Vacancy Defects

Kazi Tunvir,Seung Hoon Nahm,Amkee Kim,이학주 한국물리학회 2007 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.51 No.III

Carbon nanotubes (CNTs) offer very high mechanical properties with huge scatter. The scatter in the properties is believed to occur mainly due to the defects originated inherently during production. CNTs under a tensile load having randomly distributed vacancy defects are simulated to investigate the effect of the spatial distribution of defects on the mechanical properties. A simple random unit generation method was used to allocate the defects randomly in the single-walled nanotube's structure. The simulation was carried out a using classical molecular dynamics (MD) simulation technique in atomic scale. Defect density of 1 \% reduced the failure strength, the failure strain and Young's modulus of CNTs by as much as 42 \%, 65 \% and 2 \%, respectively, while a defect density of 8 \% lowered the properties by as much as 52 \%, 71 \% and 14 \%, respectively. The scatter in the properties due to the random distribution of the defects was found to increase with increasing number of defects in the SWNTs. For example, for a defect density of 8 \%, the standard deviations of the data for 20 sample simulations having different distributions normalized to the mean values calculated for the failure strength, the failure strain and Young's modulus were about 11 \%, 20 \% and 8 \%, respectively. The defect arrangement in the SWNT's structure is one of the key factors in determining its mechanical properties and the population of defects.

Overcoming the Curse of Early Marriage in Bangladesh

Kazi Rabeya AME 이화여자대학교 아시아여성학센터 2012 이화여자대학교 아시아여성학센터 학술대회자료집 Vol.2012 No.7

Induction of the Nuclear Proto-Oncogene c-fos by the Phorbol Ester TPA and c-H-Ras.

Kazi, Julhash U,Soh, Jae-Won Korean Society for Molecular Biology 2008 Molecules and cells Vol.26 No.5

<P>TPA is known to cooperate with an activated Ras oncogene in the transformation of rodent fibroblasts, but the biochemical mechanisms responsible for this effect have not been established. In the present study we used c-fos promoter-luciferase constructs as reporters, in transient transfection assays, in NIH3T3 cells to assess the mechanism of this cooperation. We found a marked synergistic interaction between TPA and a transfected v-Ha-ras oncogene in the activation of c-fos promoter and SRE. SRE has binding sites for TCF and SRF. A dominant-negative Ras (ras-N17) inhibited the TPA-Ras synergy by blocking the PKC-MAPK-TCF pathway. Dominant-negative RhoA and Rac1 (but not Cdc42Hs) inhibited the TPA-Ras synergy by blocking the Ras-Rho-SRF signaling pathway. Constitutively active PKCalpha and PKCepsilon showed synergy with v-Ras. These results suggest that the activation of two distinct pathways such as Ras-Raf-ERK-TCF pathway and Rho-SRF pathway are responsible for the induction of c-fos by TPA and Ras in mitogenic signaling pathways.</P>

Welfare, Work, and Women’s Empowerment: Evidence from Bangladesh’s Food for Work Program

Kazi Shahdat Kabir Rimon,Bo Wang,이종열,Chad Anderson 서울대학교행정대학원 2019 The Korean Journal of Policy Studies Vol.34 No.3

Women’s empowerment has become a major concern of both developed and developing countries across the world. Women are often largely marginalized from economic, political, and familial spheres because they tend to have limited access to economic resources, health care, and education and suffer disproportionately from the effects of poverty, discriminatory laws, practices, attitudes and gender stereotypes, and so forth. This study assesses the level of women’s empowerment by scrutinizing economic, political, and interpersonal and familial factors in rural Bangladesh. The study employed qualitative interviews and focus group discussions to determine the contribution of a food for work program that was not designed to empower women, to women’s perception of empowerment. The study interviewed 305 respondents in two districts and ten subdistricts using a purposive sampling procedure. The study showed some evidence of enhanced economic empowerment, strong evidence of increased local political empowerment, and evidence of interpersonal empowerment among women participating in the program.