Passive and Active Sampling of Benzene in Different Urban Environments in Gothenburg, Sweden     

Sofia Thorsson  IngegÄrd Eliasson 《Water, air, and soil pollution》2006,173(1-4):39-56

Urban benzene concentration and personal exposure to benzene were measured within different urban environments in Gothenburg, Sweden. Three intensive monitoring campaigns were carried out in May 2000, February 2001 and May 2001. Three different environments were selected; two central built-up areas with different traffic densities (high and low) and one large urban park. The methods used included passive and active sampling. Passive sampling was used to retrieve spatial variability in urban benzene concentrations, while active sampling aimed to give data on personal exposure levels within the designated areas. The passive sampling showed large spatial and temporal variations in urban benzene concentrations. The benzene concentrations, ranging from 1.0 to 3.1 μg m^?3, were typically two to four times higher within the high-traffic built-up area compared to the adjacent urban park. This was mainly due to the proximity to motorised traffic. A comparison between personal exposure and active stationary measurements showed that the personal exposure levels were roughly 1.5 times higher in the heavy traffic area and 1.3 times higher in the light traffic area than the fixed benzene concentrations. The personal exposure levels in the park were equal to the active stationary benzene concentration. Given the large spatial heterogeneity within urban areas, the placement of single street level point measurements becomes crucial. Care must be taken to ensure that the measurements are actually representative when using these measurements to estimate urban concentrations and exposure levels.  相似文献   

Cassini measurements of cold plasma in the ionosphere of Titan     

Wahlund JE  Boström R  Gustafsson G  Gurnett DA  Kurth WS  Pedersen A  Averkamp TF  Hospodarsky GB  Persoon AM  Canu P  Neubauer FM  Dougherty MK  Eriksson AI  Morooka MW  Gill R  André M  Eliasson L  Müller-Wodarg I 《Science (New York, N.Y.)》2005,308(5724):986-989

The Cassini Radio and Plasma Wave Science (RPWS) Langmuir probe (LP) sensor observed the cold plasma environment around Titan during the first two flybys. The data show that conditions in Saturn's magnetosphere affect the structure and dynamics deep in the ionosphere of Titan. The maximum measured ionospheric electron number density reached 3800 per cubic centimeter near closest approach, and a complex chemistry was indicated. The electron temperature profiles are consistent with electron heat conduction from the hotter Titan wake. The ionospheric escape flux was estimated to be 10(25) ions per second.  相似文献   

Reticular stimulation and chlorpromazine: an animal model for schizophrenic overarousal     

C Kornetsky  M Eliasson 《Science (New York, N.Y.)》1969,165(899):1273-1274

It has been postulated that certain schizophrenic patients are in a state of continual central excitation and that improvement in these patients after treatment with chlorpromazine is a result of the action of the drug in reducing this excitation. A model was developed to test this postulated state of central excitation. Rats were electrically stimulated in the mesencephalic reticular formation while performing a simple attention task. Stimulation or treatment with chlorpromazine impaired the performance of the animals; however, the two treatments together resulted in performance indistinguishable from that seen after injections of saline alone.  相似文献   

Differential scanning calorimetry studies on wheat starch—gluten mixtures: I. Effect of gluten on the gelatinization of wheat starch     

A.-C. Eliasson 《Journal of Cereal Science》1983,1(3):199-205

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Staling Effects When Adding Low Amounts of Normal and Heat‐Treated Barley Flour to a Wheat Bread     

Jeanette K. Purhagen  Malin E. Sj  Ann‐Charlotte Eliasson 《Cereal Chemistry》2008,85(2):109-114

The properties of a white wheat bread could be changed by adding normal or heat‐treated barley flour in small amounts (2 and 4%) to a white wheat bread recipe. Differences regarding gelatinization as well as retrogradation properties were found when analyzing the two flours in model systems. The heat‐treated flour was fully gelatinized due to prior time, temperature, and pressure treatment and could therefore absorb larger amounts of water than the other flours. In gelatinized model systems with 40% flour (dwb), the heat‐treated barley flour contained less retrograded amylopectin as compared with normal barley flour after storage for up to 14 days, whereas no differences were found with 20% flour (dwb). However, stored breads showed an increased retrogradation of amylopectin (as measured by differential scanning calorimetry [DSC]) when 2% pretreated barley flour was added as compared with addition of 2% normal barley flour. On the other hand, there were no significant differences at the 4% level. Addition of either of the barley flours resulted in less firm breads during storage as compared with the control breads. Increased water absorption in barley flour and thus increased water content in the breads or different water‐binding capacities of the flour blends could explain these results. The present study indicated that water had a stronger influence on bread firmness than the retrogradation of amylopectin. This conclusion was based on breads with pretreated barley flour being less firm than breads with normal barley flour, although the retrogradation, as determined by DSC, was higher.  相似文献   

Investigation of Chlamydophila spp. in dairy cows with reproductive disorders     

Ann-Charlotte Godin  Camilla Bj?rkman  Stina Englund  Karl-Erik Johansson  Rauni Niskanen  Stefan Alenius 《Acta veterinaria Scandinavica》2008,50(1):39

Background

Reports worldwide indicate high prevalence of Chlamydophila spp. infection in cattle. To assess the prevalence in Sweden, 525 cows in 70 dairy herds with reproductive disorders was investigated.

Methods

To detect antibodies two commercially available kits were used. Moreover, 107 specimens, including vaginal swabs, organ tissues and milk were analysed by Polymerase Chain Reaction (PCR).

Results

Two (0.4%) cows were seropositive in the Pourquier Cp. abortus ELISA. The seroprevalence with the Chekit ELISA was 28% with no difference between cases and controls. Five specimens were positive in real-time PCR and further analysed by nested PCR. Cp. pecorum was confirmed by partial omp1 DNA sequencing of the nested PCR product of vaginal swabs from control cows.

Conclusion

The results suggest that Cp. abortus infection is absent or rare in Swedish cows whereas Cp. pecorum is probably more spread. They also suggest that Chlamydophila spp. are not related to reproduction disorders in Swedish cattle.  相似文献   

Product quality deficiencies in the prefabrication industry for single-family houses     

Åsa Gustafsson  Lars Eliasson 《Wood material science & engineering》2014,9(1):1-11

In the industry for the prefabrication of single-family houses, previous research had indicated that individual companies have problems in securing the product quality of incoming softwood timber. This implies that they need to carry out a quality inspection and adjust the softwood timber when it arrives at their facility in order to fit their production. Opinions within the industry concerning product quality deficiencies differ with regard to the handling procedures and the percentage of perceived deficiencies. However, there are prefabricators of single-family houses that need to find additional areas for use for their purchased softwood timber, and spend several working hours on softwood timber to meet the quality criteria agreed upon. A previous study by Eliasson and Gustafsson puts forward a number of proposals regarding the quality deficiencies of softwood timber in this context. The present work transforms some of these proposals into hypotheses and aims at describing and understanding what affects the perception of product quality deficiencies. Questionnaires were used to collect data. The paper concludes that the purchase volume is indicated to be related to the volume portion of the deficiency in the product quality and that the level of information- and communication-technology support in production (i.e. the degree of automation) is indicated to be related to the inspection activity point. An extension of the proposed hypotheses concludes that the inspection activity point on arrival and/or on delivery into production also affects how companies do perceive product quality deficiencies. Research regarding what affects product quality deficiencies is lacking in recognizing and knowing what is aligned with the perception of product quality deficiencies; the individual companies will have an opportunity to affect and manage their appearance and thereby enhance the use of softwood timber.  相似文献   

Case Studies of the Spatial Variation of Benzene and Toluene Concentrations in Parks and Adjacent Built-up Areas     

Upmanis  H.  Eliasson  I.  Andersson-Sköld  Y. 《Water, air, and soil pollution》2001,129(1-4):61-81

The focus in the present study is the spatialvariation of anthropogenic volatile organic carbon compounds (VOC), mainly benzene and toluene, in parks and their built-up surroundings. Case studies were located in two large Scandinavian cities and measurements were made two meters aboveground level in maximum traffic periods. The results showedlarge variations in time and space but despite high pollutionlevels in the streets the air in parks and non-traffickedbuilt-up areas are substantially cleaner. The pollutantconcentration inside a large park decreased to a low level(i.e. 1/3 to 1/9 the concentration at the source) in a shortdistance (<40 m). An analysis showed that measured VOC wasassociated with fresh emissions, suggesting that the localtraffic intensity was the main governing parameter. It is,however, obvious that the spatial pattern of pollution is theresult of a combination of many different factors and variablesincluding traffic intensity, weather, local climate, land useand the character of park border.  相似文献   

Trends in food intakes in Swedish adults 1986-1999: findings from the Northern Sweden MONICA (Monitoring of Trends and Determinants in Cardiovascular Disease) Study     

Krachler B  Eliasson MC  Johansson I  Hallmans G  Lindahl B 《Public health nutrition》2005,8(6):628-635

OBJECTIVE: To determine changes in reported food frequency in adults between 1986 and 1999. DESIGN: Four consecutive cross-sectional surveys. SETTING: Counties of Norrbotten and V?sterbotten, Northern Sweden. SUBJECTS: The Northern Sweden MONICA (Monitoring of Trends and Determinants in Cardiovascular Disease) population, four independent cross-sectional surveys in 1986, 1990, 1994 and 1999. Randomly selected age-stratified samples of the population aged 25-64 years. Analysis is based on 2982 males and 3087 females who completed an 84-item food-frequency questionnaire. RESULTS: Between 1986 and 1999, average reported consumption of 3%-fat milk decreased from 42 to 7 intakes month(-1) in men and from 28 to 4 intakes month(-1) in women. Reported use of 1.5%-fat milk increased from 6 to 27 intakes month(-1) in men and from 6 to 24 in women. Monthly intakes of potatoes and root vegetables decreased from 38 to 27 in men and from 39 to 32 in women. Consumption of pasta increased from 4 to 7 intakes month(-1) in both sexes. Intakes of solid fats with 80% fat content dropped from 92 to 62 per month in men and from 78 to 52 per month in women, whereas use of 40%-fat spread increased from 12 to 22 intakes month(-1) in men and from 5 to 26 in women. Monthly intakes of vegetable oil increased from 3 to 12 in men and from 3 to 15 in women. The percentage of overweight or obese individuals (body mass index >25 kg m(-2)) increased from 52 to 65% in men and from 41 to 52% in women (P for linear trend in all these changes, <0.001). CONCLUSIONS: Our data indicate reduced consumption of foods with a high content of saturated fats. In spite of that, there is an unbroken trend towards increased obesity.  相似文献   

Interfacial Behaviour of Secalin and Rye Flour-milling Streams in Comparison with Gliadin     

L. Wannerberger  A.-C. Eliasson  A. Sindberg 《Journal of Cereal Science》1997,25(3):243-252

Secalin was extracted from rye flour and analysed by sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS-PAGE). The SDS-gel pattern showed that some proteins were composed of disulphide linked polypeptide chains. However, a gliadin sample contained more polymeric protein. The behaviour of gliadin and secalin at the air–water interface was compared using the surface balance technique. It was found that secalin was more surface active than gliadin, spreading faster and to a higher surface pressure. The influence of pH on the interfacial behaviour was also studied. The surface pressure after 45 min equilibrium of both gliadin and secalin decreased with decreasing pH. The effect was independent of the acid (hydrochloric acid, lactic acid or ascorbic acid) when compared at the same pH. The behaviour at the gas–liquid interface of five different rye flour-milling streams together with the whole (straight run) flour was also investigated. The fraction with highest protein content spread fastest and reached the highest surface pressure value. When spread on ascorbic acid at pH 3·7 the surface pressure of the flour stream with lowest protein content decreased to the greatest extent, whereas the fraction with the highest protein content was not affected. It was thus found that, although secalin showed an interfacial behaviour similar to gliadin, this behaviour was not necessarily shown by the total protein mixture in a rye flour.  相似文献