Density Functional Theory Demonstration of Anomeric Effect and Structure: Conformational and Configurational Analysis of N-2-(1,4-Dioxane)-N'-(4-methylbenzenesulfonyl)-O-(4-methylphenoxy) Isourea

Dabbagh, Hossein A.,Najafi Chermahini, Ali Reza,Modarresi-Alam, Ali Reza Korean Chemical Society 2005 Bulletin of the Korean Chemical Society Vol.26 No.8

The conformational, configurtational behavior and the structure of N-2-(1,4-Dioxane)-N'-(4-methylbenzenesulfonyl)-O-(4-methylphenoxy) isourea 1 has been studied using DFT method. Calculations predict the imidoyl amino group of the dioxane ring prefers axial conformation and that the tosyl and tolyl groups about the C=N bond retain E configuration. The anomeric effect controls the population of dioxane ring conformers, and anomers. Intramolecular hydrogen bonds contribute to the stability of E isomers. The computational analysis of 1 complements the X-ray findings.

Design-Oriented Stress-Strain Model for FRP-Confined Lightweight Aggregate Concrete

Hooshang Dabbagh,Maysam Delshad,Kasra Amoorezaei 대한토목학회 2021 KSCE JOURNAL OF CIVIL ENGINEERING Vol.25 No.1

Despite the advantages of lightweight aggregate concrete (LWAC), its brittleness in compression has limited its vast application. Jacketing by fiber-reinforced polymer (FRP) tends to be one method to overcome this negative point. The current study attempted to recognize the FRP confinement impact on the LWAC compressive monotonic behavior. Both fine and coarse aggregates were Scoria aggregate. The variables include the type and number of FRP layers; 150 × 300 mm cylindrical specimens were wrapped with 1, 2, 3, and 4 layers of glass FRP (GFRP) and carbon FRP (CFRP) strips. An investigation was performed on the monotonic stress-strain curve belonging to LWAC confined with FRP, and key points, including ultimate stress and strain on the curve, were explored. The results revealed that the key points would significantly improve by increasing FRP layers. Although the influence of GFRP confinement on enhancing the ultimate strain appears to be more considerable than the CFRP confinement, CFRP jacketing of LWAC upgrades the ultimate strength to the higher level compared to wrapping with GFRP. Based on the interpretation of experimental results, a design-oriented stress-strain model was established to predict the monotonic compressive response of Scoria-LWAC circular specimens confined with CFRP and GFRP. The validity of the model was examined. The predicted output was appropriately in line with the experimental findings.

A highly efficient computational discrimination among Streptococcal species of periodontitis patients using 16S rRNA amplicons

Al-Dabbagh, Nebras N.,Hashim, Hayder O.,Al-Shuhaib, Mohammed Baqur S. The Microbiological Society of Korea 2019 미생물학회지 Vol.55 No.1

Due to the major role played by several species of Streptococcus in the etiology of periodontitis, it is important to assess the pattern of Streptococcus pathogenic pathways within the infected subgingival pockets using a bacterial specific 16S rRNA fragment. From the total of 50 patients with periodontitis included in the study, only 23 Streptococcal isolates were considered for further analyses, in which their 16S rRNA fragments were amplified and sequenced. Then, a comprehensive phylogenetic tree was constructed and in silico prediction was performed for the observed Streptococcal species. The phylogenetic analysis of the subgingival Streptococcal species revealed a high discrimination power of the 16S rRNA fragment to accurately identify three groups of Streptococcus on the species level, including S. salivarius (14 isolates), S. anginosus (5 isolates), and S. gordonii (4 isolates). The employment of state-of-art in silico tools indicated that each Streptococcal species group was characterized with particular transcription factors that bound exclusively with a different 16S rRNA-based secondary structure. In conclusion, the observed data of the present study provided in-depth insights into the mechanism of each Streptococcal species in its pathogenesis, which differ in each observed group, according to the differences in the 16S rRNA secondary structure it takes, and the consequent binding with its corresponding transcription factors. This study paves the way for further interventions of the in silico prediction, with the main conventional in vitro microbiota identification to present an interesting insight in terms of the gene expression pattern and the signaling pathway that each pathogenic species follows in the infected subgingival site.

Exploring Cultural Conceptualisations and Metacultural Competence in Local EAP Textbooks: A Semiotic Approach

Ali Dabbagh,Mahmood Reza Atai 아시아테플 2022 The Journal of Asia TEFL Vol.19 No.1

Despite the surge of interest in evaluating culture representation in English language teaching (ELT) materials, the literature has not adequately addressed representations of culture in English for Academic Purposes (EAP) textbooks. To bridge this gap, the present study draws on the Cultural Linguistics semiotic approach to evaluate texts, tasks, and visuals in three locally-developed EAP textbooks in Iran. To this end, we triangulated interview data and narratives obtained from the materials developers of the selected textbooks and a local EAP policymaker with the analysis of texts, tasks, and images. The findings revealed that: (a) few instances of cultural schema and cultural categories were found in the textbooks; (b) mostly materials developers either were not cognizant of the notion of cultural conceptualisations when designing the textbooks or they did not consider it a significant priority in EAP textbooks due to some politico-religious reasons; (c) metacultural development tasks were barely presented in the pre-, while-, and post-reading tasks; and (d) an incompatibility prevailed among texts, tasks, and visuals regarding the presented cultural conceptualisations. The findings are discussed with reference to the need to raise EAP materials development stakeholders’ awareness about the effectiveness of cultural conceptualisations and metacultural competence in EAP education.

Density Functional Theory Demonstration of Anomeric Effect and Structure: Conformational and Configurational Analysis of N-2-(1,4-Dioxane)-N'-(4-methylbenzenesulfonyl)-O-(4-methylphenoxy) Isourea

Hossein A. Dabbagh,Ali Reza Najafi Chermahini,Ali Reza Modarresi-Alam 대한화학회 2005 Bulletin of the Korean Chemical Society Vol.26 No.8

The conformational, configurtational behavior and the structure of N-2-(1,4-Dioxane)-N'-(4-methylbenzenesulfonyl)-O-(4-methylphenoxy) isourea 1 has been studied using DFT method. Calculations predict the imidoyl amino group of the dioxane ring prefers axial conformation and that the tosyl and tolyl groups about the C=N bond retain E configuration. The anomeric effect controls the population of dioxane ring conformers, and anomers. Intramolecular hydrogen bonds contribute to the stability of E isomers. The computational analysis of 1 complements the X-ray findings.

현대 아랍 문화관에서의 지중해주의

Abdulla Al Dabbagh 부산외국어대학교 지중해연구소 2006 지중해지역연구 Vol.8 No.1

본 논문에서는 Salama Mousa와 Taha Hussain같은 저자들에 의해서 부각된 현대 아랍, 특히 이집트의 문화적 사고의 전반적이며 지배적인 영향력의 흐름을 탐구한다. 오랜 기간 동안 일방적으로 불신되어온 지중해주의를 아랍 세계의 현대 정체성 딜레마에 접근하기 위한 문화적 체계로써 재고찰한다. 제한적이고 배타적인 틀 안에서 이집트를 분석하는 것을 거부하고, 개방적 시각에서 서구 문화 동화적인 차원에서 이집트를 바라보는 문화관이 더 시기적절하며 필요한 것으로 본다. 더 나아가 "오리엔탈리즘"과 같은 용어와 형식이 유행에 뒤떨어진 듯한 어감을 주고 정치적으로 그릇된 것 같은 인상을 줌에도 불구하고, 지중해주의가 태연하게 직면하고 명백하게 해결한 문화 정체성의 문제는 이 강력한 이집트 문화관의 역사적 경험의 검토를 통해서 흥미롭게 재고된다. 세계화 시대에 문화관과 문화 정체성의 핵심적인 문제들에 대한 재평가는 합당한 일이다. "지중해 문화"라고 하는 강력한 연결고리를 통해 서구 문화 정체성 혹은 이집트 문화 정체성의 기초를 찾는 것은 분명히 혁신적이며, 대담하고 논쟁의 여지가 있는 주장이다.

Identification of Candida Species Using 26S Ribosomal RNA Gene Sequencing in Patients with Periodontitis

Nebras Nasir Al-Dabbagh,Wissam Hamid Al-Janabi,Mohammed Baqur Sahib Al-Shuhaib 대한미생물학회 2019 Journal of Bacteriology and Virology Vol.49 No.4

The infection with Candida spp. for oral cavity is being increasingly reported. However, its variations have not yet been specifically described in periodontitis. The present study was conducted to use an uniplex 26S rRNA- based amplicons to detect and discriminate Candida using only one pair of ribosomal primers. A total of 50 patients with chronic periodontitis was involved in the study. Pure Candida colonies were isolated from 23 patients and genomic DNA was extracted, and PCR was conducted. Direct DNA sequencing followed by comprehensive phylogenetic analyses were performed to confirm the identity of Candida colonies. Results indicated that the ration of Candida-infected patients was 46%, with a high prevalence of C. albicans, followed by remarkably lower ratios of C. parapsilosis, C. glabrata, C. kefyr, and C. dubliniensis respectively. Phylogenetic analyses indicated obvious discrimination amongst the analyzed Candida species as each observed species occupied a distinctive phylogenetic position. The current results reported a simple, efficient, and low-cost detection of five species of Candida without the need for other costly techniques of molecular screening. The current findings may help dentists to easily take a snapshot of the patterns of Candida infection in periodontitis cases to assess the nature and grade of infection.

Analysis of propagation characteristics of elastic waves in heterogeneous nanobeams employing a new two-step porosity-dependent homogenization scheme

Ebrahimi, Farzad,Dabbagh, Ali,Rabczuk, Timon,Tornabene, Francesco Techno-Press 2019 Advances in nano research Vol.7 No.2

The important effect of porosity on the mechanical behaviors of a continua makes it necessary to account for such an effect while analyzing a structure. motivated by this fact, a new two-step porosity dependent homogenization scheme is presented in this article to investigate the wave propagation responses of functionally graded (FG) porous nanobeams. In the introduced homogenization method, which is a modified form of the power-law model, the effects of porosity distributions are considered. Based on Hamilton's principle, the Navier equations are developed using the Euler-Bernoulli beam model. Thereafter, the constitutive equations are obtained employing the nonlocal elasticity theory of Eringen. Next, the governing equations are solved in order to reach the wave frequency. Once the validity of presented methodology is proved, a set of parametric studies are adapted to put emphasis on the role of each variant on the wave dispersion behaviors of porous FG nanobeams.

Age at Diagnosis in Bladder Cancer: Does Opium Addiction Play a Role?

Karbakhsh, Mojgan,Dabbagh, Najmeh,Shabani, Azadeh,Tabibi, Ali,Akhavizadegan, Hamed Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.8

Background: Bladder cancer is a major health problem, especially among men. Opium addiction can be an important risk factor. One important question is whether it can affect the age of onset of bladder cancer. We performed this study to evaluate this question. Materials and Methods: In a cross-section study, records of patients diagnosed with bladder carcinoma in Shahid Labbafinejad Medical Center, within 1999-2008 were included. Data were extracted from records regarding age at onset, gender, smoking status, and opioid addiction and analyzed with SPSS 13. Results: Within 10 years, 920 cases were diagnosed with bladder cancer of which 97 percent were transitional cell carcinoma. In 698 cases, opium addiction status was recorded in 21.3% (n=149). Age at diagnosis was $59.7{\pm}11.51$ (median: 60) among opioid addicts which was significantly lower than nonaddicts ($63.1{\pm}13.65$, Median: 65) (P<0.001). Conclusions: Opium addiction can decrease the age of onset of bladder cancer.

Wave dispersion characteristics of nonlocal strain gradient double-layered graphene sheets in hygro-thermal environments

Ebrahimi, Farzad,Dabbagh, Ali Techno-Press 2018 Structural Engineering and Mechanics, An Int'l Jou Vol.65 No.6

Importance of procuring adequate knowledge about the mechanical behavior of double-layered graphene sheets (DLGSs) incensed the authors to investigate wave propagation responses of mentioned element while rested on a visco-Pasternak medium under hygro-thermal loading. A nonlocal strain gradient theory (NSGT) is exploited to present a more reliable size-dependent mechanical analysis by capturing both softening and hardening effects of small scale. Furthermore, in the framework of a classical plate theory the kinematic relations are developed. Incorporating kinematic relations with the definition of Hamilton's principle, the Euler-Lagrange equations of each of the layers are derived separately. Afterwards, combining Euler-Lagrange equations with those of the NSGT the nonlocal governing equations are written in terms of displacement fields. Interaction of the each of the graphene sheets with another one is regarded by the means of vdW model. Then, a widespread analytical solution is employed to solve the derived equations and obtain wave frequency values. Subsequently, influence of each participant variable containing nonlocal parameter, length scale parameter, foundation parameters, temperature gradient and moisture concentration is studied by plotting various figures.