We analyse spectral properties of 1671 galaxies from the Stromlo–APM Survey, selected to have 15bJ17.15 and having a mean redshift z=0.05. This is a representative local sample of field galaxies, so the global properties of the galaxy population provide a comparative point for analysis of more distant surveys. We measure Hα, [O ii] λ3727, [S ii] λλ6716, 6731, [N ii] λ6583 and [O i] λ6300 equivalent widths and the D4000 break index. The 5‐Å‐resolution spectra use an 8‐arcsec slit, which typically covers 40–50 per cent of the galaxy area. We find no evidence for systematic trends depending on the fraction of galaxy covered by the slit, and further analysis suggests that our spectra are representative of integrated galaxy spectra. We classify spectra according to their Hα emission, which is closely related to massive star formation. Overall we find that 61 per cent of galaxies are Hα emitters with rest‐frame equivalent widths EW(Hα) ≳2 Å. The emission‐line galaxy (ELG) fraction is smaller than seen in the Canada–France Redshift Survey (CFRS) at z=0.2, and is consistent with a rapid evolution of Hα luminosity density. The ELG fraction and EW(Hα) increase at fainter absolute magnitudes, smaller projected area and smaller D4000. In the local Universe, faint, small galaxies are dominated by star formation activity, while bright, large galaxies are more quiescent. This picture of the local Universe is quite different from that of the distant one; bright galaxies appear to show rapidly increasing activity as one moves further back in time. We find that the ratio [N ii] λ6583/Hα is anticorrelated with EW(Hα), and that the value of 0.5 commonly used to remove the [N ii] contribution from blended Hα+[N ii] λλ6548, 6583 applies only for samples with an EW distribution similar to that seen at low redshift. We show that the [O ii], [N ii], [S ii] and Hα EWs are correlated, but with large dispersions (∼50 per cent) owing to the diversity of galaxy contents sampled. Our [O ii]–Hα relation is similar to the one derived by Kennicutt, but is 10 per cent higher at 1σ significance. We show that this relation is not valid for distant, strong [O ii] emitters with blue colours, which are more numerous than locally. This relation would overestimate the individual star formation rate by ∼50 per cent for these kinds of galaxies. We find that, on average, luminous blue ELGs are likely to be enhanced in nitrogen abundance. This suggests that in faint, low‐mass, late‐type ELGs nitrogen is a primary element, whereas in brighter, more massive galaxies nitrogen comes from a secondary source. We also find that 4 per cent of early‐type galaxies show star formation activity; this fraction seems to increase at higher redshifts.

Background-Intraocular pressure (IOP) may be partially under systemic vascular control. This study examined whether a correlation exists between blood and intraocular pressures in patients with autonomic dysfunction. Methods and Results-Eleven patients with 3 types of confirmed autonomic dysfunction (multiple system atrophy, pure autonomic failure, and baroreflex failure) were compared with age-and gender-matched controls and had IOP, systolic blood pressure, diastolic blood pressure, heart rates, and calculated mean arterial pressures (MAP) and mean ocular perfusion pressures (MOPP) measured in the supine, sitting, and standing positions. Data were analyzed with a general linear model repeated-measures ANOVA. All pressures for patients showed a dramatic decline (PϽ0.001) from supine to standing (MAP Ϫ31Ϯ14 mm Hg; IOP Ϫ6Ϯ3 mm Hg; MOPP Ϫ25Ϯ14 mm Hg) compared with controls (MAP ϩ4Ϯ7 mm Hg; IOP Ϫ1Ϯ2 mm Hg; MOPP ϩ6Ϯ7 mm Hg). There was no significant change in heart rate from supine to standing for patients compared with controls (Pϭ0.648). Within both the multiple system atrophy (nϭ5) and pure autonomic failure (nϭ4) groups, all initial pressures were similar to control pressures in the supine position, whereas patients with baroreflex failure (nϭ2) had higher mean pressures than respective controls in the supine position. Conclusions-In autonomic dysfunction, a large decrease in MAP correlated with a large decrease in IOP. These data suggest that the autonomic nervous system, perhaps through an influence on systemic blood pressure, has a significant role in IOP regulation.

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In the UK around 10-12% of schoolchildren and around 6-10% of adults have asthma. In any year, at least one in 10 school children will experience symptoms of wheezing. Cigarette smoke is a major respiratory irritant and damp and mould in homes can precipitate asthma.' Recently, the association between air pollution and respiratory disease has become topical. The pollutants associated most frequently with respiratory health problems are sulphur dioxide (SO2-produced during the burning of fossil fuels and from car exhausts),2 ozone, and small particulates.3 An association between levels of traffic pollutants, traffic density, and increased levels of childhood asthma has been shown.4