| 1. |
- Sjödin, Fredrik, et al.
(författare)
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Measures against preschool noise and its adverse effects on the personnel : an intervention study
- 2014
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Ingår i: International Archives of Occupational and Environmental Health. - : Springer Science and Business Media LLC. - 0340-0131 .- 1432-1246. ; 87:1, s. 95-110
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the study was to analyze the exposure effects of different types of noise measures carried out at preschools. The project was carried out as an intervention study. The investigation included 89 employees at 17 preschools in the northern part of Sweden. Individual noise recordings and recordings in dining rooms and play halls were made at two departments in each preschool. The adverse effects on the employees were analyzed with validated questionnaires and saliva cortisol samples. Evaluations were made before and 1 year after the first measurement. Between the two measurements, measures were taken to improve the sound environments at the preschools. The effects of the measures varied a lot, with respect to both the sound environments and health. Regarding acoustical measures, significant changes were seen for some of the variables analyzed. For most of the tested effects, the changes, however, were very small and non-significant. The effects of organizational measures on the objective and subjective noise values were in overall less pronounced. Acoustical measures improved the subjectively rated sound environment more than organizational measures. This may be due to the high work effort needed to implement organizational measures. Even though the sound level was not lower, the personnel experienced improvements of the sound environment.
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| 2. |
- Sjödin, Fredrik, et al.
(författare)
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Minimizing speech contribution using different microphone noise dosimeter positions
- 2012
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Ingår i: Proceedings of BNAM 2012. - Odense : University of Southern Denmark. - 9788799540006
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Use of noise dosimeter recordings in low sound level environments is often problematic due to the voice contribution from the carrier. The aim of the study was to find a microphone position with low speech contribution while still providing an accurate sound level recording. An experiment with different microphone positions was conducted in a low sound reverberation room. Two types of noise dosimeters were used (Brüel & Kjaer 4445 and Larson Davis Spark 706-Atex). In repeated measurements the carrier was instructed to read a text chapter during 60 seconds and at a speech of level about 60 dB(A), acquired by practice, with different background noise and noise levels. White noise and preschool noise was used at sound levels 50, 60, 70 and 80 dB(A). The voice contribution to the background noise level was then measured. Three microphone positions were tested; on the shoulder, above the ear and on the back of the head. The position with the microphone placed behind the head of the carrier had the lowest speech contribution, less than 2 dB(A) to the background noise at 70 dB(A). This compared to positions right above the ear 6 dB(A and on the shoulder 12 dB(A).
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| 3. |
- Sjödin, Fredrik, et al.
(författare)
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Noise and stress effects on preschool personnel
- 2012
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Ingår i: Noise & Health. - : Medknow. - 1463-1741 .- 1998-4030. ; 14:59, s. 166-178
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Tidskriftsartikel (refereegranskat)abstract
- The aim of the study was to analyze the presence of stress-related health problems among preschool employees and the way in which these reactions are related to noise and other work parameters. The investigation included 101 employees at 17 preschools in Umea County, located in northern Sweden. Individual noise recordings and recordings in dining rooms and play halls were made at two departments from each preschool. The adverse effects on the employees were analyzed by use of different validated questionnaires and by saliva cortisol samples. Stress and energy output were pronounced among the employees, and about 30 of the staff experienced strong burnout syndromes. Mental recovery after work was low, indicated by remaining high levels of stress after work. The burnout symptoms were associated with reduced sleep quality and morning sleepiness. Cortisol levels supported the conclusion about pronounced daily stress levels of the preschool employees.
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| 4. |
- Sjödin, Fredrik, et al.
(författare)
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Noise exposure and auditory effects on preschool personnel
- 2012
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Ingår i: Noise & Health. - : Medknow Publications. - 1463-1741 .- 1998-4030. ; 14:57, s. 72-82
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Tidskriftsartikel (refereegranskat)abstract
- Hearing impairments and tinnitus are being reported in an increasing extent from employees in the preschool. The investigation included 101 employees at 17 preschools in Umeå county, Sweden. Individual noise recordings and stationary recordings in dining rooms and play halls were conducted at two departments per preschool. The effects of noise exposures were carried out through audiometric screenings and by use of questionnaires. The average individual noise exposure was close to 71 dB(A), with individual differences but small differences between the preschools. The noise levels in the dining room and playing halls were about 64 dB(A), with small differences between the investigated types of rooms and preschools. The hearing loss of the employees was significantly higher for the frequencies tested when compared with an unexposed control group in Sweden. Symptoms of tinnitus were reported among about 31% of the employees. Annoyance was rated as somewhat to very annoying. The voices of the children were the most annoying noise source. The dB(A) level and fluctuation of the noise exposure were significantly correlated to the number of children per department. The preschool sound environment is complex and our findings indicate that the sound environment is hazardous regarding auditory disorders. The fluctuation of the noise is of special interest for further research.
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| 5. |
- Sjödin, Fredrik, 1978-
(författare)
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Noise in the preschool : health and preventive measures
- 2012
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This thesis is based on noise recordings and health evaluations carried out at preschools in the northern part of Sweden. Sound level recordings were made on individuals and by use of stationary devices in dining rooms and play halls. Health evaluations were based on ratings by use of questionnaires and by analyses of cortisol.The average equivalent individual noise exposure was 71 dB(A). The average equivalent noise levels in the dining room and playing halls were 64 dB(A). The hearing loss of the employees was significantly higher for the frequencies tested than in an unexposed control group. Symptoms of tinnitus were reported among 31% of the employees. Noise annoyance was rated as somewhat to very annoying, and the voices of the children were the most annoying noise source. The dB(A) level and fluctuations of the noise exposure were significantly correlated with the number of children per department. Stress and energy output were pronounced among the employees. About 30% of the staff experienced strong burnout syndromes. Mental recovery was low as indicated by noise fatigue and high levels of stress after work. Increased cortisol levels during work were associated with higher number of children present at the department.An essential finding of the thesis was that noise and noise sources may impair the pedagogic work, thereby increasing the work load of employees. It is concluded that noise exposure in the preschool, isolated or in combination with other stressors, plays a fundamental role in the building up of acute as well as long term stress. An intervention study implementing six acoustical and seven organizational measures was tested, aimed to improve the noise situation in the departments. Acoustical measures improved the noise situation as well as the rated noise experiences better than the organizational measures.
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| 6. |
- Sjödin, Fredrik, et al.
(författare)
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Tinnitus, noise and health effects in preschool environments
- 2012
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Ingår i: Proceedings of BNAM 2012. - Odense : University of Southern Denmark. - 9788799540006
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The study included 93 employees at 17 preschools in the county of Umeå located in northern part ofSweden. Personal daily noise dosimeter recordings were made at five representative work days.Stationary noise recordings were made during the same days at two departments of each preschool, in theplaying halls and in the dining rooms. Besides audiometric tests, the employees rated their experiences ofthe noise, hearing and tinnitus as well as well as different health effects, on validated questionnaires.Tinnitus was reported among 31 per cent of the participants. The study group was dichotomized intoemployees with or without tinnitus. Employees with tinnitus reported higher prevalence of subjectivehearing loss, higher experiences of elevated sound levels at work, anxiety of the noise at work, chestpressure/pain, burn out symptoms, depression and reduced sleep quality. Significant differences wereseen for shoulder tension/pain. No group differences were seen for the objective personal or stationarynoise measures or the number of children present at the department. The results of the study are discussedin terms of underlying causes and the way in which the symptom interfere with experiences and healtheffects of the employees.
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| 7. |
- Sjödin, Åke, et al.
(författare)
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Wear particles from road traffic : A field, laboratory and modelling study - final report
- 2010
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This report is an outcome of a major research effort within the Swedish National Road Vehicle Emission Research Programme EMFO, carried out 2005-2008 in collaboration between IVL, Lund University, the City of Stockholm and VTI. Within the project extensive data have been collected by a variety of methods for measuring, sampling and analysing the chemical composition of primarily three different fractions of particulate matter - PM10, PM2.5, PM1. Emphasis has been on the PM10 fraction, in the case of which preferably the major Swedish cities experience significant problems with complying with the legally binding air quality standards. The collected data originate from indoor measurements in controlled runs with the VTI circular road simulator as well as ambient air measurements at both street and roof level in a variety of Swedish cities. Based on elemental (metals etc.) source profiles of various sources to the different particle fractions, derived from the literature or from measurements carried out within the project, several different receptor models (e.g. COPREM, PMF) were applied to the collected data to derive the contributions from exhaust, brake wear, tyre wear, road surface wear, long-range transport etc., to the measured concentrations of PM10 and other particle fractions in urban environments. Furthermore, from the measurements, emission factors (expressed in grams per vehkm) for the various particle fractions, as well as for a large number of contained metals (about 30 metals) were derived for a major city street in Stockholm. Total emission factors as well as emission factors for each of the different source types (exhaust, brake wear, tyre wear and road surface wear) have also been derived from the measurements.
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| 8. |
- Sjödin, Åke, et al.
(författare)
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Wear particles from road traffic - a field, laboratory and modelling study. Final report
- 2010
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- The present report forms the final report from a major research project within the Swedish National Road Vehicle Emission Research Programme EMFO, carried out during the period 2005-2008. The project was carried out in collaboration between IVL, Lund University, SLB analys and VTI. Within the project extensive data have been collected by a variety of methods for measuring, sampling and analysing the chemical composition of different fractions of airborne particulate matter, with emphasis on the PM10 fraction. Collected data originate from indoor measurements in controlled runs with a circular road simulator as well as ambient air measurements at both street and roof level in a variety of Swedish cities. Based on elemental (metals etc.) source profiles of various sources to the different particle fractions, derived from the literature or from measurements carried out within the project, several different receptor models (e.g. COPREM, PMF) were applied to the collected data to derive the contribution from exhaust, brake wear, tyre wear, road surface wear, long-range transport etc., to the measured concentrations of PM10 and other particle fractions in urban environments. An important result of the project is the evidence for the great importance of studded tyres for the high PM10 concentration levels that occur in many Swedish cities during winter and early spring. According to the controlled indoor experiments with the road simulator studded tyres give rise to ten times higher emissions of PM10 than non-studded (friction) winter tyres, while PM10 emissions caused by summer tyres is almost negligible
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| 9. |
- Ahlinder, Jon, et al.
(författare)
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Increased knowledge of Francisella genus diversity highlights the benefits of optimised DNA-based assays
- 2012
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Ingår i: BMC Microbiology. - : Springer Science and Business Media LLC. - 1471-2180. ; 12, s. 220-
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Tidskriftsartikel (refereegranskat)abstract
- Background: Recent advances in sequencing technologies offer promising tools for generating large numbers of genomes, larger typing databases and improved mapping of environmental bacterial diversity. However, DNA-based methods for the detection of Francisella were developed with limited knowledge about genetic diversity. This, together with the high sequence identity between several Francisella species, means there is a high risk of false identification and detection of the highly virulent pathogen Francisella tularensis. Moreover, phylogenetic reconstructions using single or limited numbers of marker sequences often result in incorrect tree topologies and inferred evolutionary distances. The recent growth in publicly accessible whole-genome sequences now allows evaluation of published genetic markers to determine optimal combinations of markers that minimise both time and laboratory costs. Results: In the present study, we evaluated 38 previously published DNA markers and the corresponding PCR primers against 42 genomes representing the currently known diversity of the genus Francisella. The results highlight that PCR assays for Francisella tularensis are often complicated by low specificity, resulting in a high probability of false positives. A method to select a set of one to seven markers for obtaining optimal phylogenetic resolution or diagnostic accuracy is presented. Conclusions: Current multiple-locus sequence-typing systems and detection assays of Francisella, could be improved by redesigning some of the primers and reselecting typing markers. The use of only a few optimally selected sequence-typing markers allows construction of phylogenetic topologies with almost the same accuracy as topologies based on whole-genome sequences.
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| 10. |
- Birdsell, Dawn N, et al.
(författare)
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Francisella tularensis subsp. tularensis group A.I, United States
- 2014
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Ingår i: Emerging Infectious Diseases. - : Centers for Disease Control and Prevention (CDC). - 1080-6040 .- 1080-6059. ; 20:5, s. 861-865
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Tidskriftsartikel (refereegranskat)abstract
- We used whole-genome analysis and subsequent characterization of geographically diverse strains using new genetic signatures to identify distinct subgroups within Francisella tularensis subsp. tularensis group A.I: A.I.3, A.I.8, and A.I.12. These subgroups exhibit complex phylogeographic patterns within North America. The widest distribution was observed for A.I.12, which suggests an adaptive advantage.
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