Search

Type 1 diabetes (T1DM) is an autoimmune disorder with multiple genetic and environmental risk factors that are still poorly understood. The signal transducer and activator of transcription (STAT) proteins play a pivotal role in immune-cell genesis and regulation. This study aimed to determine the effect of rs1053005 single nucleotide polymorphism (SNP) in 3′-UTR of STAT3 mRNA on the susceptibility to T1DM in an Iranian population. PCR-RFLP was conducted on 250 T1DM patients and 250 control cases to assess STAT3 rs1053005 polymorphism. Moreover, several bioinformatics tools were employed to identify the candidate miRNAs targeting the STAT3 mRNA region under study as well as the effect of rs1053005 on their binding site. Significant variations in the distribution of genotypes and alleles were seen between cases and controls. The comparison results of the frequency of AA, AG, and GG genotypes between T1DM patients and control groups were 49.2% versus 64.8%, 39.2 versus 30%, and 11.6 versus 5.2%, respectively. Individuals who carried GG genotype were at 2.93-fold increased risk of developing T1DM and the G allele was associated with 1.79-fold higher T1DM risk. Bioinformatics analysis demonstrated that due to rs1053005, the interaction of 3 miRNAs were broken, 3 were weakened, 2 were reinforced, and 4 binding sites were created. The result of this study indicates an association between STAT3 rs1053005 and T1DM susceptibility which may be due to interference of the SNP with native-binding site of some predicted miRNAs. [ABSTRACT FROM AUTHOR]

This study investigated the relationship between English language learners' Instagram engagement and second language (L2) motivation. It also aimed to determine engagement types (behavioral, cognitive, and affective engagement) as predictors of L2 motivation. Through stratified sampling, we recruited 102 Iranian users engaged in learning English via the Instagram platform as an informal learning context. The participants were Persian native speakers learning English as a foreign language. They were 81 males and 21 females at different levels of English proficiency whose ages ranged from 16 to 62. A multimethod approach, with a quantitative/qualitative design, was adopted to conduct the study. The quantitative phase had a correlational design in which two questionnaires were administered to measure English learners' engagement in language learning on Instagram and their L2 motivation. Furthermore, a semi-structured interview was conducted in the qualitative phase. Results revealed a positive and significant relationship between the English language learners' engagement on Instagram and their L2 motivation. Moreover, cognitive engagement was the sole predictor of learners' L2 motivation. The findings have pedagogical implications for both English instructors and L2 learners, which are discussed in light of the literature. [ABSTRACT FROM AUTHOR]

Abstract: An efficient and direct eco-friendly protocol for the preparation of 1-amidoalkyl-2-naphthols employing a multi-component, one-pot condensation reaction between β-naphthol, aromatic or aliphatic aldehydes and benzamide or acetamide in the presence of dodecylphosphonic acid under solvent-free conditions has been described. [Copyright &y& Elsevier]

We report the preparation of aromatic and aliphatic carboxylic acid esters in the presence of triphenylphosphine dibromide or triphenylphosphine diiodide and N,N-dimethylaminopyridine in dichloromethane at room temperature in good to excellent yields. [ABSTRACT FROM AUTHOR]

An efficient, green and ecofriendly procedure has been developed using Fe3O4@SiO2–imid–PMAn as a magnetic catalyst for a rapid and improved synthesis of 2,4,5-trisubstituted and 1,2,4,5-tetrasubstituted imidazoles under solvent-free conditions and microwave irradiation in excellent yields. The reactions under conventional heating conditions were compared with the microwave-assisted reactions. The operational simplicity, practicability and applicability of this protocol to various substrates make it an interesting alternative to previous procedures. The present approach offers several advantages such as short reaction times, high yields, simplicity of operation, easy work-up, a cleaner reaction and ease of recovery and reusability of the catalyst using a magnetic field. Also, the nanocatalyst can be easily recovered by the application of a magnetic field and reused for the next reactions at least 5 times without distinct deterioration in catalytic activity. SEM, BET, DLS and leaching of the catalyst after each reaction cycle were investigated. [ABSTRACT FROM AUTHOR]

Highlights: [•] Preparation of the magnetic nanocatalyst. [•] Immobilization of PMA nanoparticles on imidazole functionalized Fe3O4@SiO2. [•] Identification of catalyst by XRD, TEM, DLS, FE-SEM, FT-IR, BET and VSM. [•] Catalyst recycling by external magnetic field. [•] The preparation of 1-amidoalkyl-2-naphthols as biologically compounds. [Copyright &y& Elsevier]

Copper-based composites have interesting properties and they are widely used in electronics, packaging, and automotive applications. In the present work, the cross-accumulative roll bonding (CARB) process was used to fabricate Cu-based composites with Zn and Brass reinforcing layers. The experimental observations revealed a clear relationship between rolling strain and plastic instabilities including the necking and rupture of reinforcement. However, the grain refinement was observed on Cu, Zn, and Brass layers after seven CARB cycles, indicating the positive impact of rolling rotation on obtaining the ultrafine grains. Better ductility of Brass also resulted in finer grains. This also led to more significant improvement in mechanical properties. During the CARB process, the hardness of Zn and Brass increased from 59 HV and 250 HV to 89 HV and 310 HV, respectively. [ABSTRACT FROM AUTHOR]