We present spectroscopic results for all galaxies observed with the Spitzer Infrared Spectrograph (IRS) which also have total infrared fluxes f IR measured with the Infrared Astronomical Satellite (IRAS), also using AKARI photometry when available. Infrared luminosities and spectral energy distributions (SEDs) from 8 µm to 160 µm are compared to polycyclic aromatic hydrocarbon (PAH) emission from starburst galaxies or mid-infrared dust continuum from AGN at rest frame wavelengths ∼ 8 µm. A total of 301 spectra are analyzed for which IRS and IRAS include the same unresolved source, as measured by the ratio f ν (IRAS 25 µm)/f ν (IRS 25 µm). Sources have 0.004 < z < 0.34 and 42.5 < log L IR < 46.8 (erg s −1 ) and cover the full range of starburst galaxy and AGN classifications. Individual spectra are provided electronically, but averages and dispersions are presented. We find that log [L IR /νL ν (7.7 µm)] = 0.74 ± 0.18 in starbursts, that log [L IR /νL ν (7.7 µm)] = 0.96 ± 0.26 in composite sources (starburst plus AGN), that log [L IR /νL ν (7.9 µm)] = 0.80 ± 0.25 in AGN with silicate absorption, and log [L IR /νL ν (7.9 µm)] = 0.51 ± 0.21 in AGN with silicate emission. L IR for the most luminous absorption and emission AGN are similar and 2.5 times larger than for the most luminous starbursts. AGN have systematically flatter SEDs than starbursts or composites, but their dispersion in SEDs overlaps starbursts. Sources with the strongest far-infrared luminosity from cool dust components are composite sources, indicating that these sources may contain the most obscured starbursts.

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Aims: Antibiotic resistance of different bacteria requires the development of alternative approaches for overcoming this phenomenon. The antibacterial effects of iron oxide (Fe 3 O 4 ) nanoparticles (NPs) (from 50 to 250 lg ml À1 ) on Escherichia coli antibiotic-resistant strains have been aimed. Methods and Results: The study was performed with ampicillin-resistant E. coli DH5a-pUC18 and kanamycin-resistant E. coli pARG-25 stains. Specific growth rate of bacteria (l), lag phase duration and colony-forming units (CFU) were determined to evaluate growth properties. Fe 3 O 4 NPs (average size of 10Á64 AE 4Á73 nm) coated with oleic acid and synthesized by modified coprecipitation method were used. The medium pH, H + efflux, membrane H + conductance, redox potential determinations and H 2 yield assay were done using potentiometer methods. Growth properties were changed by NPs in concentration-dependent manner. NPs decreased (up to twofold) H + -fluxes through bacterial membrane more in E. coli in the presence of the N,N 0dicyclohexylcarbodiimide, inhibitor of ATPase, indicating that antibacterial activity of these NPs was connected with ATP-associated metabolism. Membrane-associated H 2 production was lowered up to twofold. Moreover, the synergetic interactions of NPs and antibiotics were found: combination of NPs and antibiotics provided the higher H + conductance, lower H + -fluxes and H 2 yield. Conclusions: Fe 3 O 4 NPs can be suggested as alternative antibacterial agents, which can substitute antibiotics in different applications. Significance and Impact of the Study: The antibacterial effects of Fe 3 O 4 NPs on the growth properties and membrane activity of E. coli antibiotic-resistant strains have been demonstrated. These NPs have potential as antibacterial agents, which can substitute for antibiotics in bacterial disease treatment in biomedicine, pharmaceutical and environmental applications.

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