Aims. Despite strong interest in the starburst phenomenon in extragalactic astronomy, the concept remains ill-defined. Here we use a strict definition of starburst to examine the statistical properties of starburst galaxies in the local universe. We also seek to establish links between starburst galaxies, post-starburst (hereafter postburst) galaxies, and active galaxies. Methods. Data were selected from the Sloan Digital Sky Survey DR7. We applied a novel method of treating dust attenuation and derive star formation rates, ages, and stellar masses assuming a two-component stellar population model. Dynamical masses are calculated from the width of the Hα line. These masses agree excellently with the photometric masses. The mass (gas+stars) range is ∼10 9-10 11.5 M. As a selection criterion for starburst galaxies, we use, the birthrate parameter, b = SFR/ SFR , requiring that b ≥ 3. For postburst galaxies, we use, the equivalent width of Hδ in absorption with the criterion EW Hδ,abs ≥ 6 Å. Results. We find that only 1% of star-forming galaxies are starburst galaxies. They contribute 3−6% to the stellar production and are therefore unimportant for the local star formation activity. The median starburst age is 70 Myr roughly independent of mass, indicating that star formation is mainly regulated by local feedback processes. The b-parameter strongly depends on burst age. Values close to b = 60 are found at ages ∼10 Myr, while almost no starbursts are found at ages >1 Gyr. The median baryonic burst mass fraction of sub-L * galaxies is 5% and decreases slowly towards high masses. The median mass fraction of the recent burst in the postburst sample is 5−10%. A smaller fraction of the postburst galaxies, however, originates in non-bursting galaxies. The age-mass distribution of the postburst progenitors (with mass fractions >3%) is bimodal with a break at logM(M) ∼ 10.6, above which the ages are doubled. The starburst and postburst luminosity functions (LFs) follow each other closely until M r ∼ −21, when active galactic nuclei (AGNs) begin to dominate. The postburst LF continues to follow the AGN LF, while starbursts become less significant. This suggests that the number of luminous starbursts is underestimated by about one dex at high luminosities, because of having large amounts of dust and/or being outshone by an AGN. It also indicates that the starburst phase preceded the AGN phase. Finally, we look at the conditions for global gas outflow caused by stellar feedback and find that massive starburst galaxies are susceptible to such outflows.

BackgroundMany studies have focused on the implication of the serotonin and dopamine systems in neuroadaptive responses to the recreational drug 3,4-methylenedioxy-metamphetamine (MDMA). Less attention has been given to the major excitatory neurotransmitter glutamate known to be implicated in schizophrenia and drug addiction. The aim of the present study was to investigate the effect of repeated intermittent MDMA administration upon gene-transcript expression of the glutamate transporters (EAAT1, EAAT2-1, EAAT2-2), the glutamate receptor subunits of AMPA (GluR1, GluR2, GluR3), the glutamate receptor subunits of NMDA (NR1, NR2A and NR2B), as well as metabotropic glutamate receptors (mGluR1, mGluR2, mGluR3, mGluR5) in six different brain regions. Adolescent male Sprague Dawley rats received MDMA at the doses of 3 × 1 and 3 × 5 mg/kg/day, or 3× vehicle 3 hours apart, every 7th day for 4 weeks. The gene-transcript levels were assessed using real-time PCR validated with a range of housekeeping genes.ResultsThe findings showed pronounced enhancements in gene-transcript expression of GluR2, mGluR1, mGluR5, NR1, NR2A, NR2B, EAAT1, and EAAT2-2 in the cortex at bregma +1.6. In the caudate putamen, mRNA levels of GluR3, NR2A, and NR2B receptor subunits were significantly increased. In contrast, the gene-transcript expression of GluR1 was reduced in the hippocampus. In the hypothalamus, there was a significant increase of GluR1, GluR3, mGluR1, and mGluR3 gene-transcript expressions.ConclusionRepeated intermittent MDMA administration induces neuroadaptive changes in gene-transcript expressions of glutamatergic NMDA and AMPA receptor subunits, metabotropic receptors and transporters in regions of the brain regulating reward-related associative learning, cognition, and memory and neuro-endocrine functions.

Chloramine-T is a small molecular oxidizing agent that has been widely used as a disinfectant since the beginning of this century. It is generally used in a 5% solution but it is also supplied in powder form. Sporadic case reports of immediate-type sensitization to this agent associated with symptoms of asthma, rhinitis and urticaria have appeared during recent decades. In one of the reports, specific IgE antibodies in sera of four patients who developed asthmatic symptoms after exposure to chloramine-T were demonstrated using a radioimmuno-assay. Three cases of bronchial asthma in workers who had handled chloramine-T powder are described in the present report. Positive skin-prick test reactions to chloramine-T were observed and specific IgE antibodies to human serum albumin treated with chloramine-T were detected using the classic radioallergosorbent (RAST) technique in all three patients.

The exposure to organic acid anhydrides was estimated to be low, and yet, IgG antibodies to OAA were observed in some subjects. The prevalence of work-related symptoms from the eyes and the airways was relatively high among the powder painters, and these symptoms, but not the lung volumes, were clearly related to exposure. The symptoms were probably caused by irritative properties of the powder paint dust.

Background: During production of sugar beet (Beta vulgaris) seeds in greenhouses, workers frequently develop allergic symptoms. The aim of this study was to identify and characterize possible allergens in sugar beet pollen.