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Interleukin-1β (IL-1β), the prototypical pro-inflammatory cytokine, is produced by macrophages following exposure to bacterial products. Its role is to act upon several cell types at the site of infection to stimulate the production of pro-inflammatory molecules that will cause increase in vascular permeability. Therefore, IL-1β regulates the initiation and development of acute inflammation that may have a role in mammary gland defense during mastitis. Single nucleotide polymorphisms (SNPs) in the 5'-flanking region of this gene can modulate IL-1β function. The aim of the present study was to discover and analyze SNPs in promoter region of IL-1B gene in cattle (Bos taurus). The 5'-flanking region of IL-1B gene was screened by single strand conformation polymorphism (SSCP) in Holstein and Iranian local cattle breeds (50 local and 50Holstein). A total of 4 distinct SSCP patterns were observed, which further revealed 5 novel SNPs upon sequence analysis in Iranian local breed. From the SNPs identified in this region, polymorphism at nucleotide position -534 was found to lie in the vicinity of potential GATA and ZNF transcription factor binding sites. The SNPs identified at -383 position was shown to be present within the putative ETS factor and also core sequence of CARE transcription factor. Two SNPs at positions -534 and -340 were found within the EBF binding site. The SNPs identified in the 5'-flanking region of IL-1B gene may serve as potential candidate genetic marker(s) for disease resistant traits in cattle.

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Disjoining of spot welds in steel sheets because of fatigue failure is one of the main reasons for noise in used cars. Fatigue life of spot welding connections of ST12 steel sheets, used in car industry, with 6mm nugget diameter and subjected to uniaxial dynamic shear load is studied and determined in this research. Sheet thickness and other spot welding parameters including weld pitch are considered and compared according to C-G006 standard utilizing the test sample selected according to DIN50165 standard. ABAQUS and FE-SAFE soft wares are used for static and fatigue life analysis respectively. To generate Stress-Number of life cycle (S-N) diagram, the equivalent fully reversed load is determined using Goodman and Gerber theories since the applied load is unidirectional. The resultant finite element results were verified experimentally by a fatigue test machine designed and manufactured during this study by the authors. The finite element results showed a good agreement with Gerber criterion and it was concluded that with increase in sheet thickness, both static strength and fatigue life would be increased. The results also depicts that the weld pitch has no effect on fatigue life. Stress – life graph for 6mm nugget diameter spot weld on ST12 sheet is the most important outputs of this research that can be used in automobile industry.

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The Melanocortin-1 Receptor MC1R is encoded by the extension locus, playing a fundamental role in the determination of coat color in a number of mammalian species. However, so far there has been no report regarding the Single Nucleotide Polymorphisms (SNPs) of the MC1R promoter region and the potential association of its SNPs with coat color in sheep (Ovis aries). Throughout the present study, the promoter region of the MC1R gene was screened using Single Strand Conformation Polymorphism SSCP and DNA sequencing in the Karakul breed of sheep. A total of 4 distinct SSCP patterns were observed which revealed 3 novel SNPs and an insertion/deletion of 26 nucleotides upon sequence analysis in the analyzed population. In silico analysis of the MC1R promoter sequence predicted no consensus TATA-box motif at an appropriate position but detected multiple putative transcription factor binding sites for Ets, AML-1a , NF-E2, MZF1, USF, Oct-1 and GATA-1. The analysis of identified polymorphic sites also showed that the polymorphism at nucleotide position -89 relative to the start codon abolishes the USF transcription factor binding site. The SNP identified at the -100 position is located within a putative AML-1a transcription factor binding site. The insertion of 26 nucleotides at position -126 made a putative binding site for the MOK2 transcription factor. The possible functional activity of the identified genetic variations could be confirmed using gene expression analysis.