115 research outputs found
A new methanol solvate and Hirshfeld analysis of Ï-stacking in 2,3,6,7,10,11-hexahydroxytriphenylene solvates
The structure of 2,3,6,7,10,11-hexahydroxytriphenylene (hhtp)
methanol monosolvate, C18H12O6•CH3OH, has triclinic
symmetry (space group P1). The compound has a threedimensional
layered network structure formed by intermolecular
hydrogen bonding. Structure analysis with Hirshfeld
surfaces is shown to be a sensitive method for comparing π -stacking effects in the five known solvates of hhtp. The title
structure shows slightly weaker π -stacking than the dihydrate,
but stronger π -stacking than the other three solvates
Survey context and question wording affects self reported annoyance due to road traffic noise: a comparison between two cross-sectional studies
<p>Abstract</p> <p>Background</p> <p>Surveys are a common way to measure annoyance due to road traffic noise, but the method has some draw-backs. Survey context, question wording and answer alternatives could affect participation and answers and could have implications when comparing studies and/or performing pooled analyses. The aim of this study was to investigate the difference in annoyance reporting due to road traffic noise in two types of surveys of which one was introduced broadly and the other with the clearly stated aim of investigating noise and health.</p> <p>Methods</p> <p>Data was collected from two surveys carried out in the municipality of Malmö, southern Sweden in 2007 and 2008 (n = 2612 and n = 3810). The first survey stated an aim of investigating residential environmental exposure, especially noise and health. The second survey was a broad public health survey stating a broader aim. The two surveys had comparable questions regarding noise annoyance, although one used a 5-point scale and the other a 4-point scale. We used geographic information systems (GIS) to assess the average road and railway noise (L<sub>Aeq,24h</sub>) at the participants' residential address. Logistic regression was used to calculate odds ratios for annoyance in relation to noise exposure.</p> <p>Results</p> <p>Annoyance at least once a week due to road traffic noise was significantly more prevalent in the survey investigating environment and health compared to the public health survey at levels > 45 dB(A), but not at lower exposure levels. However no differences in annoyance were found when comparing the extreme alternatives "never" and "every day". In the study investigating environment and health, "Noise sensitive" persons were more likely to readily respond to the survey and were more annoyed by road traffic noise compared to the other participants in that survey.</p> <p>Conclusions</p> <p>The differences in annoyance reporting between the two surveys were mainly due to different scales, suggesting that extreme alternatives are to prefer before dichotomization when comparing results between the two. Although some findings suggested that noise-sensitive individuals were more likely to respond to the survey investigating noise and health, we could not find convincing evidence that contextual differences affected either answers or participation.</p
Queen Nefertari, the royal spouse of pharaoh Ramses II: a multidisciplinary investigation of the mummified remains found in her tomb (QV66)
Queen Nefertari, the favourite Royal Consort of Pharaoh Ramses II (Ancient Egypt, New Kingdom, 19th Dynasty c. 1250 BC) is famous for her beautifully decorated tomb in the Valley of the Queens. Her burial was plundered in ancient times yet still many objects were found broken in the debris when the tomb was excavated. Amongst the found objects was a pair of mummified legs. They came to the Egyptian Museum in Turin and are henceforth regarded as the remains of this famous Queen, although they were never scientifically investigated. The following multidisciplinary investigation is the first ever performed on those remains. The results (radiocarbon dating, anthropology, paleopathology, genetics, chemistry and Egyptology) all strongly speak in favour of an identification of the remains as Nefertari's, although different explanations-albeit less likely-are considered and discussed. The legs probably belong to a lady, a fully adult individual, of about 40 years of age. The materials used for embalming are consistent with Ramesside mummification traditions and indeed all objects within the tomb robustly support the burial as of Queen Nefertari.Michael E. Habicht, Raffaella Bianucci, Stephen A. Buckley, Joann Fletcher, Abigail S. Bouwman, Lena M. Ćhrström, Roger Seiler, Francesco M. Galassi, Irka Hajdas, Eleni Vassilika, Thomas Böni, Maciej Henneberg, Frank J. RĂŒhl
Road traffic noise and children's inattention
BACKGROUND: An increasing number of children are exposed to road
traffic noise levels that may lead to adverse effects on health
and daily functioning. Childhood is a period of intense growth
and brain maturation, and children may therefore be especially
vulnerable to road traffic noise. The objective of the present
study was to examine whether road traffic noise was associated
with reported inattention symptoms in children, and whether this
association was mediated by sleep duration. METHODS: This study
was based on the Norwegian Mother and Child Cohort Study
conducted by the Norwegian Institute of Public Health. Parental
reports of children's inattention at age 8 were linked to
modelled levels of residential road traffic noise. We
investigated the association between inattention and noise
exposure during pregnancy (n = 1934), noise exposure averaged
over 5 years (age 3 to 8 years; n = 1384) and noise exposure at
age 8 years (n = 1384), using fractional logit response models.
The participants were children from Oslo, Norway. RESULTS: An
association with inattention at age 8 years was found for road
traffic noise exposure at age 8 years (coef = .0083, CI =
[.0012, .0154]; 1.2% point increase in inattention score per 10
dB increase in noise level), road traffic noise exposure average
for the last 5 years (coef = .0090, CI = [.0016, .0164]; 1.3%
point increase/10 dB), and for pregnancy road traffic noise
exposure for boys (coef = .0091, CI = [.0010, .0171]), but not
girls (coef = -.0021, CI = [-.0094, .0053]). Criteria for doing
mediation analyses were not fulfilled. CONCLUSION: Results
indicate that road traffic noise has a negative impact on
children's inattention. We found no mediation by sleep duration
Noise measurements and rail traffic development
Public involvement in the planning process is a prerequisite for democratic outcomes. Environmental issues regarding impacts of sound tend to be limited to mere exercises in noise estimation and guideline values. Such information is difficult for the layman to understand, and such a lack of understanding produces shortcomings in the democratic process. In addition to decibel calculations interpretable by experts, the sonic environment also can be described in more accessible ways. This article reports on a concrete planning case, the widening of the railway through Ă
karp in southern Sweden, where the usual calculations of equivalent noise and maximum noise are undergoing critical analysis. In order to complement the noise description, a new measurement has been devised, âhigh noise time,â which is equal to the total time per 24 hours in which trains pass through a place without stopping. The frequency and duration of the passing of trains may be a better measure of disturbance than the maximum noise peak per passage or the equivalent (average) noise level distributed over 24 hours. Film technology also has been developed as a method for recording the frequency and duration of train passage
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