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The nonlinear amplitude modulation of dust-ion acoustic wave (DIAW) is studied in the presence of nonextensive distributed electrons in dusty plasmas with stationary dust particles. Using the reductive perturbation method (RPM), the nonlinear Schrödinger equation (NLSE) which governs the modulational instability (MI) of the DIAWs is obtained. Modulational instability regions and the growth rate of nonlinear waves are discussed. It is shown that the wave characters are affected by the value of nonextensive parameter and also relative density of plasma constituents.

Astronomical compact objects, like neutron stars, are made of Fermi-Dirac distributed hadronic matter which has a wide range of densities. In this work, non-relativistic dynamics of high density hadronic plasmas with shear and bulk viscosities are studied. The propagation of localized waves in media with hadronic gas equation of state is investigated. Initially, localized lumps are propagated as breaking and shock waves in inviscid media. It is shown that in the viscous case, the localized waves can travel longer distances before changing into shock or breaking profiles.

Background and Objectives: To provide data on the occurrence of classical K. pneumoniae (cKp) and hypervirulent Klebsi- ella pneumoniae (hvKp) strains harboring the gene encoding regulator of mucoid phenotype A (rmpA) and evaluated charac- teristics of virulence biomarkers, carbapenemase, extended-spectrum-β-lactamase (ESBL)-producing, and capsule serotypes among K. pneumoniae clinical isolates collected in the south of Iran. Materials and Methods: A total of 400 K. pneumoniae isolates were collected. First, the K. pneumoniae isolates were screened for rmpA gene by PCR, and then they were characterized for the presence of the virulence genes (pagO, iucA, iroB, luxR), capsular serotype genes (K1, K2, K5, K20, K54, and K57), carbapenemase (bla , bla IMP, bla , bla KPC , bla ,bla OXA-48 , and bla ) and ESBL (bla CTX-M SHV and blaTEM) genes. For all K. pneumoniae isolates phenotypic tests in- clude of string test and disk diffusion test were performed. Results: In total, 16 (4%) hvKp-rmpA+ and 384 (96%) cKp were observed. Of hvKp-rmpA+ strains, 16 (100%) were carried pagO, iroB, and luxR genes, and 13 (81.3%) strains harbored iucA gene. The most prevalent capsular type genes were K1 (62%) and K2 (19%) in hvKp-rmpA+ strains. The incidence of bla SHV gene in hvKp and cKp was 94% (15/16) and 87.5% (336/384), respectively. The cKp isolates carried bla. NDM (30/384; 7.8%) gene.   Conclusion: Our data suggest that the incidence of hvKp was low. Also, hvKp-rmpA+ strains have less antibiotic resistance than cKp isolates. Serotypes K1 and K2, and bla SHV gene were strongly associated with hvKp-rmpA+.