Amylin is a 37 residue peptide with a disulfide bridge between the residues 2 and 7. This hormone co-secreted with insulin by pancreatic islet b-cells. It has been reported that amylin is able to form amyloid fibrils. Although these fibrils are not related with the manifestation of type 2 diabetes, they have a significant role in the aggravation of diabetic condition. In this study, the potential of amyloid formation and stability of amylin has been studied in 10 species with high sequence similarity (80%), with the use of molecular Dynamics simulation. Based on the structure of human amylin (2L86.pdb from Protein Data Bank) homology modeling technique was used to create 10 different species amylin. Simulation was performed using GROMACS version 4.6.1, with a 10 ns duration and 500K. The systems were solvated with SPC water molecules. Secondary structure content was calculated using DSSP. Other analyses such as energy, solvent accessible surface, radius of gyration, RMSD and RMSF were performed, using GROMACS. Human and Rat amylin were selected as non-aggregating peptides respectively. During simulation amylin showed remarkable Structural changes, and in most cases α-helical structures were lost. In some species with aggregating amylin, b -sheets were formed at the end of the simulation. Between the studied species, Pongoabelii peptide, one of the two species of orangutans used in this study, showed more stability alongside with more similarity to human amylin. Based on these results, this amylin specie could be proposed as a potential therapeutic peptide, as an alternative to rat amylin.

Find a way to cope with the changing environments and organizational survival has become a major challenge among management researchers in recent years. The dynamic capabilities view has gained particular importance. Reviews of the dynamic capabilities literatures reveal that survey effects of environmental dynamism on dynamic capabilities, is one of the research requirements. This paper examines the relationship between dynamic capabilities and environmental Dynamics. So, a model of dynamic capabilities (including sensing capability, seizing capability and reconfiguration capability) and environmental Dynamics (including technology and market Dynamics) constructs was designed. The data were collected from the questionnaire. Questionnaires were completed by senior managers of production companies in Tehran stock exchange. We used SmartPLS. Results showed the relationship between environmental Dynamics and dynamic capabilities as higher-level construct in the model is significant. Also, technological Dynamics have a positive impact on sensing capability, seizing capability and reconfiguration capability. Market Dynamics have a positive impact on sensing capability and seizing capability too.

Aims: Understanding the Structural Dynamics of unmanaged oak coppices is crucial, as many of the world’s forests remain unmanaged. While previous studies have focused on coppice Dynamics in mesic woodlands, there needs to be a more significant gap in understanding these processes in semi-arid regions. The study aims to examine the Structural modifications, successional trajectories, and floristic diversity within semi-arid oak coppices in the Zagros Mountains, utilizing a comprehensive dataset obtained from an extensive land survey. Materials & Methods: The study was conducted in a 175 km strip of Zagros Mountain forests dominated by Quercus brant ii. Ninety-four even-aged stands from 14 forests were selected. Structural attributes were evaluated, including tree density, basal area, canopy cover, and floristic diversity measures. A list of vascular flora was documented for each successional stage using the Raunkiær plant life-form classification. Data analysis involved polar ordination, clustering, and multivariate techniques.  Findings: Density, Holdridge complexity index, basal area, and cover were identified as the most influential variables. Two main trajectories, progressive and retrogressive, were identified, with eight successional stages. Significant differences in Structural variables were observed across trajectories, with floristic diversity peaking in the middle stages. The later stages of the progressive trajectory showed a significant increase in the relative cover and basal area of Fraxinus rotundifolia. The study demonstrates the existence of a progressive successional trajectory in unmanaged coppice forests influenced by disturbances. Stand age, mean diameter of sprout clumps, and flora diversity do not solely determine the successional stages within this trajectory. Conclusion: While transforming Zagros Mountain oak coppice into high forests is unlikely, there is potential for redirecting succession toward more resilient and diverse ecosystems. We recommend management interventions beyond protection, promoting uneven-aged stands, increasing density and cover, and encouraging species like Fraxinus. These strategies can enhance ecological integrity and foster sustainable woodland ecosystems in the Zagros region.