The effects of urban green space and road proximity to indoor traffic-related PM2.5, NO2, and BC exposure in inner-city schools.

BACKGROUND: Since there are known adverse health impacts of traffic-related air pollution, while at the same time there are potential health benefits from greenness, it is important to examine more closely the impacts of these factors on indoor air quality in urban schools. OBJECTIVE: This study investigates the association of road proximity and urban greenness to indoor traffic-related fine particulate matter (PM2.5), nitrogen dioxide (NO2), and black carbon (BC) in inner-city schools. METHODS: PM2.5, NO2, and BC were measured indoors at 74 schools and outdoors at a central urban over a 10-year period. Seasonal urban greenness was estimated using the Normalized Difference Vegetation Index (NDVI) with 270 and 1230 m buffers. The associations between indoor traffic-related air pollution and road proximity and greenness were investigated with mixed-effects models. RESULTS: The analysis showed linear decays of indoor traffic-related PM2.5, NO2, and BC by 60%, 35%, and 22%, respectively for schools located at a greater distance from major roads. The results further showed that surrounding school greenness at 270 m buffer was significantly associated (p < 0.05) with lower indoor traffic-related PM2.5: -0.068 (95% CI: -0.124, -0.013), NO2: -0.139 (95% CI: -0.185, -0.092), and BC: -0.060 (95% CI: -0.115, -0.005). These associations were stronger for surrounding greenness at a greater distance from the schools (buffer 1230 m) PM2.5: -0.101 (95% CI: -0.156, -0.046) NO2: -0.122 (95% CI: -0.169, -0.075) BC: -0.080 (95% CI: -0.136, -0.026). These inverse associations were stronger after fully adjusting for regional pollution and meteorological conditions. IMPACT STATEMENT: More than 90% of children under the age of 15 worldwide are exposed to elevated air pollution levels exceeding the WHO's guidelines. The study investigates the impact that urban infrastructure and greenness, in particular green areas and road proximity, have on indoor exposures to traffic-related PM2.5, NO2, and BC in inner-city schools. By examining a 10-year period the study provides insights for air quality management, into how road proximity and greenness at different buffers from the school locations can affect indoor exposure.

Lack of observable intoxication in humans with high plasma alcohol concentrations.

Judging the degree of human alcohol intoxication is an important clinical, social, and medicolegal matter. Assessing the degree of intoxication is not always easy by direct patient observation. Observational instruments have been used in forensic science, medical, and social situations in an endeavor to measure alcohol intoxication. The validity of these observational instruments must be questioned. In this study, twenty-one patients with alcohol related complaints presenting to major city emergency departments were studied using one such observational instrument, the Alcohol Symptom Checklist (ASC). Three independent emergency medicine physicians applied the criteria of ASC to the twenty-one patients and obtained a plasma alcohol concentration (PAC) for correlation purposes. Individual correlation coefficients (r = 0.182, r = 0.202, r = 0.200) and a composite correlation coefficient (r = 0.235) demonstrated lack of correlation between PAC and ASC. This lack of correlation is supported by clinical observations of experienced emergency department personnel.

Neurotransmitter amino acids in the CNS. II. Some changes in amino acid levels in rat brain synaptosomes during and after in vitro anoxia and simulated ischemia.

The effects of in vitro anoxia and membrane depolarization by veratridine on the uptake and release of amino acids were investigated in suspensions of synaptosomes isolated from the forebrains of rats. It was observed that GABA, aspartate and glutamate were released from synaptosomes in anaerobic conditions and upon addition of veratridine in a time-dependent manner. The release of the two latter amino acids was faster and more pronounced than that of GABA. The other amino acids were not affected in any systematic way by either condition. Re-introduction of oxygen or addition of tetrodotoxin to veratridine-treated synaptosomes resulted in the re-uptake of GABA, aspartate and glutamate, which was much faster and more complete for GABA than for the acidic amino acids, especially at acid pH values. The amounts of aspartate and glutamate in the incubation mixture remained constant during all the manipulations whereas that of GABA increased by about 30% during anaerobiosis, in agreement with the results obtained during in vivo ischemia. It is postulated that synaptosomes which utilize glutamate and aspartate as neurotransmitters are more damaged by anoxia and depolarization with veratridine than the population which utilizes GABA. These observations may explain reports that those neurons which are thought to receive major glutamatergic input are particularly sensitive to the lack of oxygen.

Audiogenic seizures in rats: relation to noradrenergic neurons of the locus coeruleus.

Bilateral lesions involving the nucleus locus coeruleus produced a substantial decrease in the forebrain noradrenaline concentrations. Lesioned animals showed an increased susceptibility to audiogenic seizures. It is supposed that noradrenergic neurons, belonging to the locus coeruleus, play an inhibitory role in the seizure mechanism.

Papaverine, drug-induced stereotypy and catalepsy and biogenic amines in the brain of the rat.

The effects of papaverine on haloperidol-induced catalepsy and apomorphine-induced stereotypy as well as brain monoamines concentrations in rats were studied. Papaverine increased cataleptogenic effect of haloperidol whilst reduced stereotypy induced by apomorphine. Slight but significant decrease in brain dopamine concentration was observed in rats treated with papaverine. The present study indicates that papaverine has influences upon dopaminergic mechanisms in the brain.

Drum dispersion equation for Littrow-type prism spectrometers.

A simple analytic procedure has been developed for calibrating the wavelength drum of a Littrow-type prism spectrometer. Only three measured drum readings are required to specify the drum calibration over a broad wavelength range (uv to ir) with an accuracy of the order of the instrumental accuracy. This procedure can be applied to different prism materials for which measurements of refractive index have been performed. It is based on an approximate expression, derived from geometrical optics, relating the drum reading D(lambda) to the calculated refractive index n(lambda): D= A - B(a(2) - n(2))((1/2)). The index n(lambda) is calculated from the appropriate parametric equation. The temperature for the n(lambda) values need not be exactly that of the prism temperature during measurements. This expression was investigated for wavelengths in the range 0.3 micro to 2.25 micro using a sodium chloride prism. Computed drum positions D agreed with measured drum positions to within experimental error. Unknown wavelengths were computed from their measured drum positions to within the accuracy of the measurements.