Comparison of Three Advanced Data Assimilation Techniques for Assimilating Ground-based PM<SUB>2.5</SUB> over North-East Asia

Uzzal Kumar Dash,Soon-Young Park,Jinhyeok Yu,Chul Han Song 한국대기환경학회 2021 한국대기환경학회 학술대회논문집 Vol.2021 No.10

To compare the analyses and prediction performances, three-dimensional variational (3DVAR), Ensemble Kalman Filter (EnKF) and Ensemble Square Root Filter (EnSRF) data assimilation (DA) techniques were applied to the WRF-CMAQ model for assimilating surface PM2.5 over North-East Asia. For the purpose of direct comparison among these DA methods, same background error variances calculated by NMC method were used in each DA system. New analyses were produced every 6 hours (reanalysis) for the KORUS-AQ campaign period, from 00 UTC 1 May to 18 UTC 11 June, 2016. 48-h predictions were also performed using each 00 UTC analyses as initial condition during the same period. Additionally, a control experiment was performed without DA. Both reanalysis and prediction using three DA techniques were compared against control run and observations. Overall results suggest that two ensemble-based DA techniques outperformed 3DVAR and the performances between EnKF and EnSRF are comparable. For Example, the reduced Normalized Mean Bias (NMB) over control run for 3DVAR, EnKF and EnSRF were 12.2%, 26.9% and 28.1% respectively for first day prediction over South Korea. Even for the second day prediction, EnKF and EnSRF performances were better than 3DVAR although the reduced NMB were comparatively smaller.

ON SOME NEW CLASSES OF COMPACT-LIKE BITOPOLOGICAL SPACES

B M Uzzal Afsan 충청수학회 2020 충청수학회지 Vol.33 No.2

In this paper, we have introduced a new type of covering property β t (ωr,s) -closedness, stronger than P t (ωr,s) -closedness [3] in terms of (r, s)-β-open sets [9] and β-ωt-closures in bitopological spaces along with its several characterizations via filter bases and grills [15] and various properties. Further grill generalizations of β t (ωr,s) -closedness (namely, β t (ωr,s) -closedness modulo grill) and associated concepts have also been investigated.

P^t_{(ω_r,s)}-CLOSED SPACES AND PRE-(ω_r,s)t-θ_f-CLUSTER SETS

Afsan, Bin Mostakim Uzzal,Basu, Chanchal Kumar Korean Mathematical Society 2011 대한수학회논문집 Vol.26 No.1

Using (r, s)-preopen sets [14] and pre-${\omega}_t$-closures [6], a new kind of covering property $P^t_{({\omega}_r,s)}$-closedness is introduced in a bitopological space and several characterizations via filter bases, nets and grills [30] along with various properties of such concept are investigated. Two new types of cluster sets, namely pre-(${\omega}_r$, s)t-${\theta}_f$-cluster sets and (r, s)t-${\theta}_f$-precluster sets of functions and multifunctions between two bitopological spaces are introduced. Several properties of pre-(${\omega}_r$, s)t-${\theta}_f$-cluster sets are investigated and using the degeneracy of such cluster sets, some new characterizations of some separation axioms in topological spaces or in bitopological spaces are obtained. A sufficient condition for $P^t_{({\omega}_r,s)}$-closedness has also been established in terms of pre-(${\omega}_r$, s)t-${\theta}_f$-cluster sets.

앙상블 칼만필터를 사용한 PM<SUB>2.5</SUB> 자료동화 연구

박순영,Uzzal Kumar Dash,유진혁,송철한 한국대기환경학회 2019 한국대기환경학회 학술대회논문집 Vol.2019 No.11

EnKF와 EnSRF 기반의 PM<SUB>2.5</SUB> 관측 자료동화를 위한 배경오차공분산의 수평 및 연직 규모 분석

박순영,Uzzal Kumar Dash,유진혁,송철한 한국대기환경학회 2021 한국대기환경학회 학술대회논문집 Vol.2021 No.10

관측 자료동화 기법은 수치모델의 불확실성을 줄이기 위해 모델과 관측의 오차 정보를 토대로 모델 예측결과와 관측자료를 합쳐 참값에 가까운 초기장(분석장)을 만드는 기술이다. 다양한 자료동화 기술이 예보에 활용되고 있지만 모델의 오차를 어떻게 정의하고 반영하는가에 관한 문제가 자료동화 성능을 결정적으로 좌우한다. 특히, 대기오염 수송모델에 자료동화를 적용할 경우 관측 농도를 공간적으로 어떤 범위의 수정이 필요한지는 다음 시간의 수송 및 확산의 초기조건을 결정하므로 매우 중요하다. 본 연구에서는 앙상블 기반의 두 자료동화 방법인 EnKF와 EnSRF에 적용된 배경오차공분산(BEC)의 수평 및 연직 규모분석을 수행하였고 이를 변분자료동화방법인 3DVAR와 비교하여 그 특징을 살펴보았다. 3DVAR에 사용된 BEC는 같은 시점을 예측한 두 다른 예측 기간의 차이를 모델의 오차로 정의하여 기후적으로 결정하는 NMC 방법이 적용된다. 그 결과 관측 지점에서 자료동화에 의한 분석 증분은 가우시안 형태의 원형으로 분포한다. 앙상블 기반의 자료동화는 짧은 시간의 앙상블 예측을 통해 앙상블 평균을 참값으로 가정하여 오차공분산을 계산하기 때문에 자료동화 시점의 대기 흐름이 반영된 분석증분이 나타나는 특징이 있다. EnKF와 EnSRF에 사용된 BEC의 수평 · 연직 규모분석결과와 기상 변수와의 상관성도 함께 분석하였다.

Diversity Analysis of Bangladeshi Coastal Rice Landraces (Oryza sativa) for Morpho-Physiological and Molecular Markers’Responses to Seedling Salinity Tolerance

Hafsa Sultana,Uzzal Somaddar,Swadesh Chandra Samanta,Abul Kashem Chowdhury,Gopal Saha 한국육종학회 2022 Plant Breeding and Biotechnology Vol.10 No.2

Development of salt tolerance in rice through breeding program is mainly depends on the salinity responses of thepotential rice germplasms. Coastal rice landraces of Bangladesh possess diverse morphological and physiological responses to salinity. Hence, our target is to identify candidate salt-tolerant coastal rice genotypes as a new source of salt tolerance (12 dS/m). Here, weannotated 20 Bangladeshi coastal Aus landrace rice regarding their phenotypic and genetic relatedness to salinity tolerance throughmultivariate analyses of five morpho-physiological traits namely, salt injury score (SIS), ion-leakage, chlorophyll concentration,root-shoot reduction percentage and profiling of DNA using simple sequence repeat (SSR). Based on the standard evaluation score(SES) the salt-induced coastal rice landraces were grouped into highly susceptible (HS), susceptible (S), moderately tolerant (MT),tolerant (T) and highly tolerant (HT). Besides, a canonical discrimination analysis of the mean trait values of five morpho-physiologicalparameters confirmed the above mentioned five categories of salinity tolerance. Based on all morpho-physiological parameters onegenotype (Kalihytta) as highly tolerant (HT), two genotypes (Manikmuri and Monsur IRRI) as tolerant (T) and five genotypes (Nara,Iratom 27, Matichak, Abdul high IRRI and Parija) were identified as moderately tolerant (MT) against salinity. Finally, the molecularcharacterization using two SSR markers (RM493 and RM3412) revealed Kalihytta, Nara, Iratom 27, Parija, Lal jamaibabu andFullbadam, as tolerant against salt stress. Our candidate salt tolerant Aus rice genotypes could be useful as novel sources of salttolerance for thriving salt-tolerant high yielding varieties in the coastal ecosystem of Bangladesh.

Influential Factors of Social Entrepreneurial Intention in Bangladesh

AKHTER, Ayeasha,HOSSAIN, Md. Uzzal,ASHEQ, Ahmed Al Korea Distribution Science Association 2020 The Journal of Asian Finance, Economics and Busine Vol.7 No.8

The concept of social entrepreneurship (SE) is gaining attention in developing economies for the purpose of greater societal welfare maximization. Still, findings in the field of SE studies have been riddled with conflicting results and counterstatement. Also, the determinants of developing SE are not robustly investigated in developing economies like Bangladesh. This context has mobilized the authors of this current study to focus on determining student's intention to pursue SE as their career choice. Hence, the study aims to examine the predictive determinants of social entrepreneurial intentions (SEI) among Bangladeshi students. The study has investigated the influence of entrepreneurial self-efficacy, social support, prior experience, and educational support on SEI. The survey was conducted from a public university of Bangladesh, and 231 students participated in the study. Questionnaire items under each construct variable have been adopted from pre-tested research studies. Five-point Likert scale questionnaire was applied to measure the variables. SPSS version 23.0 has been used for statistical analysis through which correlation and multiple regression analysis were conducted to measure the impact of the independent variables on SEI. Results exhibited that self-efficacy, social support, and educational support positively and significantly predicted SEI, while prior experience does not influence SEI.

Molecular Marker Development for the Rapid Differentiation of Black Rot Causing Xanthomonas campestris pv. campestris Race 7

Yeo-Hyeon Kim,Sopheap Mao,Nihar Sahu,Uzzal Somaddar,Hoy-Taek Kim,Masao Watanabe,박종인 한국식물병리학회 2023 Plant Pathology Journal Vol.39 No.5

Xanthomonas campestris pv. campestris (Xcc) is a plant pathogen of Brassica crops that causes black rot disease throughout the world. At present, 11 physiological races of Xcc (races 1-11) have been reported. The conventional method of using differential cultivars for Xcc race detection is not accurate and it is laborious and time-consuming. Therefore, the development of specific molecular markers has been used as a substitute tool because it offers an accurate and reliable result, particularly a quick diagnosis of Xcc races. Previously, our laboratory has successfully developed race-specific molecular markers for Xcc races 1-6. In this study, specific molecular markers to identify Xcc race 7 have been developed. In the course of study, whole genome sequences of several Xcc races, X. campestris pv. incanae, X. campestris pv. raphani, and X. campestris pv. vesicatoria were aligned to identify variable regions like sequence-characterized amplified regions and insertions and deletions specific to race 7. Primer pairs were designed targeting these regions and validated against 22 samples. The polymerase chain reaction analysis revealed that three primer pairs specifically amplified the DNA fragment corresponding to race 7. The obtained finding clearly demonstrates the efficiency of the newly developed markers in accurately detecting Xcc race 7 among the other races. These results indicated that the newly developed marker can successfully and rapidly detect Xcc race 7 from other races. This study represents the first report on the successful development of specific molecular markers for Xcc race 7.

Molecular Characterization of Legionellosis Drug Target Candidate Enzyme Phosphoglucosamine Mutase from Legionella pneumophila (strain Paris): An In Silico Approach

Hasan, Md. Anayet,Mazumder, Md. Habibul Hasan,Khan, Md. Arif,Hossain, Mohammad Uzzal,Chowdhury, A.S.M. Homaun Kabir Korea Genome Organization 2014 Genomics & informatics Vol.12 No.4

The harshness of legionellosis differs from mild Pontiac fever to potentially fatal Legionnaire's disease. The increasing development of drug resistance against legionellosis has led to explore new novel drug targets. It has been found that phosphoglucosamine mutase, phosphomannomutase, and phosphoglyceromutase enzymes can be used as the most probable therapeutic drug targets through extensive data mining. Phosphoglucosamine mutase is involved in amino sugar and nucleotide sugar metabolism. The purpose of this study was to predict the potential target of that specific drug. For this, the 3D structure of phosphoglucosamine mutase of Legionella pneumophila (strain Paris) was determined by means of homology modeling through Phyre2 and refined by ModRefiner. Then, the designed model was evaluated with a structure validation program, for instance, PROCHECK, ERRAT, Verify3D, and QMEAN, for further structural analysis. Secondary structural features were determined through self-optimized prediction method with alignment (SOPMA) and interacting networks by STRING. Consequently, we performed molecular docking studies. The analytical result of PROCHECK showed that 95.0% of the residues are in the most favored region, 4.50% are in the additional allowed region and 0.50% are in the generously allowed region of the Ramachandran plot. Verify3D graph value indicates a score of 0.71 and 89.791, 1.11 for ERRAT and QMEAN respectively. Arg419, Thr414, Ser412, and Thr9 were found to dock the substrate for the most favorable binding of S-mercaptocysteine. However, these findings from this current study will pave the way for further extensive investigation of this enzyme in wet lab experiments and in that way assist drug design against legionellosis.

Molecular Characterization of Legionellosis Drug Target Candidate Enzyme Phosphoglucosamine Mutase from Legionella pneumophila (strain Paris): An In Silico Approach

Md. Anayet Hasan,Md. Habibul Hasan Mazumder,Md. Arif Khan,Mohammad Uzzal Hossain,A. S. M. Homaun Kabir Chowdhury 한국유전체학회 2014 Genomics & informatics Vol.12 No.4

The harshness of legionellosis differs from mild Pontiac fever to potentially fatal Legionnaire’s disease. The increasingdevelopment of drug resistance against legionellosis has led to explore new novel drug targets. It has been found thatphosphoglucosamine mutase, phosphomannomutase, and phosphoglyceromutase enzymes can be used as the mostprobable therapeutic drug targets through extensive data mining. Phosphoglucosamine mutase is involved in amino sugarand nucleotide sugar metabolism. The purpose of this study was to predict the potential target of that specific drug. For this,the 3D structure of phosphoglucosamine mutase of Legionella pneumophila (strain Paris) was determined by means ofhomology modeling through Phyre2 and refined by ModRefiner. Then, the designed model was evaluated with a structurevalidation program, for instance, PROCHECK, ERRAT, Verify3D, and QMEAN, for further structural analysis. Secondarystructural features were determined through self-optimized prediction method with alignment (SOPMA) and interactingnetworks by STRING. Consequently, we performed molecular docking studies. The analytical result of PROCHECK showedthat 95.0% of the residues are in the most favored region, 4.50% are in the additional allowed region and 0.50% are in thegenerously allowed region of the Ramachandran plot. Verify3D graph value indicates a score of 0.71 and 89.791, 1.11 forERRAT and QMEAN respectively. Arg419, Thr414, Ser412, and Thr9 were found to dock the substrate for the most favorablebinding of S-mercaptocysteine. However, these findings from this current study will pave the way for further extensiveinvestigation of this enzyme in wet lab experiments and in that way assist drug design against legionellosis.