Estimates of pedestrian exposure to atmospheric pollution using high-resolution modelling in a real traffic hot-spot.

Atmospheric pollution is a very relevant risk for the human health, in particular in urban environments, where most people lives and high levels of pollution are found. Population exposure is traditionally estimated through concentration recorded at air quality monitoring stations (AQMS) or modelled at a spatial resolution of the order of 1 km2. However, these methodologies have limitations in urban areas where strong gradients of concentration, even in the same street, exist. In addition, the movements of pedestrians make difficult to compute reliable estimates of pollutant concentration to which people are exposed to. In this context, the main objective of this study is to estimate the exposure of pedestrians to ambient nitrogen oxides (NOx) concentrations with high spatial resolution in a real urban traffic hot-spot under different methodologies. To achieve this objective, a novel methodology which combines high-resolution NOx concentrations from computational fluid dynamic (CFD) simulations with the pedestrian flows obtained by pedestrian mobility microsimulations is applied to an urban area of Madrid, Spain. High-resolution maps show pedestrian exposure peaks, at bus stops and crosswalks, that cannot be captured by the simpler methods based on spatial average concentration (SAC) or concentration measured in an AQMS. Total daily exposure obtained is 1.19 · 109 person s µg m-3, while SAC and AQMS concentration methods yielded 9-23% and 30-40% lower values. In conclusion, the proposed methodology allows to determine the areas with higher exposure in order to design local strategies to reduce the impact on human health. In addition, from a more general point of view, the total exposure in the studied area is better estimated by using spatial average concentration than through concentration recorded by AQMS. The assessment of the spatial representative of AQMS becomes necessary to use AQMS concentration to evaluate air quality and population exposure of an urban area.

Evaluation of a CFD-based approach to estimate pollutant distribution within a real urban canopy by means of passive samplers.

The distribution of pollutants is spatially heterogeneous within urban streets making difficult to build a realistic concentration map. In this paper, a methodology based on computational fluid dynamic modeling with Reynolds-averaged Navier-Stokes approach is used to compute maps of concentration for a period of several weeks. The methodology is evaluated by comparing simulation results against experimental data from two different campaigns where a large number of passive samplers deployed in an area with heavy vehicular traffic in Madrid (Spain). The evaluation shows that the methodology is able to reproduce the general pattern of several-week averaged pollutant distribution in an urban area with heavy vehicular traffic, resolving the spatial variability up to a resolution of 1-2m. In addition, the model results fit satisfactorily the time evolution of the pollutant concentration measured at an air quality station deployed in the studied area. However, problems were detected close to zones with complex emissions patterns (tunnels, street forks, etc.), where the model compared poorly against passive sampler measurements. A preliminary assessment of the uncertainties induced in the numerical methodology due to consider NO2 as non-reactive pollutant under winter conditions indicates that it would be an acceptable approach for this particular case study. Overall, our analysis contributes to raise the confidence in that approached similar to the one presented in this study can be adopted for dealing with several aspects of the air quality management such as air quality assessment, optimization of the location of measurement stations, and the evaluation of air pollution reduction strategies.

Midline spikes. EEG and clinical features.

Clinical features of 40 patients with midline spikes on EEG were compared with those of age- and sex-matched controls. Seizure incidence was significantly greater in the study group than in the controls (85% v 45%). Tonic-clonic seizures were the most frequent type. Eighteen patients from the study group had additional focal or generalized epileptiform abnormalities. This subgroup had a significantly greater incidence of seizures than patients with only midline spikes (100% v 73%). Midline spikes are more common in children and markedly activated with sleep. They must be distinguished from normal sleep transients.

Bilateral independent periodic lateralized epileptiform discharges. Clinical significance.

Clinical data on 18 patients whose EEGs showed bilateral independent periodic lateralized epileptiform discharges (BIPLEDs) were reviewed and compared with those of 45 patients with periodic lateralized epileptiform discharges (PLEDs). A recent stroke was the most frequent cause of PLEDs (33%), while anoxic encephalopathy (28%) and CNS infection (28%) accounted for the majority of BIPLEDs. Focal neurologic deficits, focal seizures, and focal computed tomographic scan abnormalities were frequent in those with PLEDs, while coma predominated in the group with BIPLEDs (72% vs 24%). Mortality was also higher in patients with BIPLEDs--61% vs 29%.

Number and sex preferences among the young and old.

PIP: 1345 respondents froms elected Laguna Lake area municipalities (Philippines) were interviewed in order to provide a preliminary description of the preference for number and sex of children of 5 respondent groups - the youth, newly married couples, couples where the wife was at the peak of the childbearing period, menopausal women, and grandparents. The analysis undertaken included the Coombs preferences scales, cross tabulations, percentage distirubtion and mean. Preferences for the number of children by category, age and sex of respondent indicated an underlying preference for moderate to large families. A trend towards the preference for small families was evident among the female and male respondents in the youth category. The preference for the number of children appeared to be positively related to the age of respondent. Females tended to prefer slightly smaller family sizes than males. Male respondents preferred male children, and female respondents preferred female children.^ieng

The value of children: the old people's view.

PIP: Personal interviews were conducted with 104 menopausal women and 205 grandparents from selected Laguna Lake (Philippines) area municipalities in an effort to study the benefits and cost of children from the viewpoints of grandparents and menopausal women and to investigate how such costs and benefits are related to the respondents' perceptions of family size and family formation. The data collected included age, sex, desired number and sex of children in the respondent's family, ideal age at marriage in years, reasons for ideal age at marriage for males, ideal birth interval, and number and age of children when problems were experienced. The following were included among the survey results: 1) children were valued as sources of inspiration and happiness and as eventual sources of economic assistance along with the feeling of accomplishment and satisfaction gained from watching the children grow and develop; 2) the disadvantages of having children fell under the categories of economic costs, emotional costs, and curtailment of freedoms; 3) the average desired family size of menopausal women was 4 children, and it was 5 children for grandparents; 4) the perceived ideal age at marriage of the respondents varied slightly; 5) an interval of 1-2 years between marriage and the birth of the 1st child was considered appropriate by 74% of the grandparents and by 63% of the menopausal women; and 6) economic costs of children and poor health were the primary reasons for the difficulties encountered by the respondents in raising their children.^ieng

The Filipino family in the year 2000.

PIP: Secondary sources of data from the National Demographic Surveys of 1968 and 1973 and National Censuses of 1903, 1939, 1948, 1960 and 1970 were used to present trends, patterns, and differentials in household size, structure and headship on the national and regional levels; changes in the stages of the family life cycle; trends in nuptiality during the 20th century on the national and regional levels; and nuptiality projections up to the year 2000. The analysis undertaken included means, percentages, ratios, projections, and comparisons of the results of the 2 surveys. Included among the results in terms of household size and structure, age composition of households, patterns and differentials in headship rates, life cycle of the family, and nuptiality were the following: 1) more than 1/2 of the households had 6 family members or more; 2) the most number of children occurred when the head of the family was between the ages of 24 and 44 years, when sex, urban-rural residence, and region were controlled; 3) an increasing trend in headship rates was exhibited by the single male and the widowed and divorced/separated female; 4) in 1973, the average interval between marriage and birth of the 1st child was 1.7 years; and 5) examination of past and recent regional nuptiality trends indicated a significant delay in age at marriage for females.^ieng