| 11. |
|
|
| 12. |
|
|
| 13. |
- Ahl, Astrid, 1943-
(författare)
-
Läraren och läsundervisningen : En studie av åldersintegrerad pedagogisk praktik med sex- och sjuåringar
- 1998
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation is about reading instruction in six mixed-aged classes, called child schools, with six and seven year old children. The overall questions of this study were: How did the teachers in child schools organise work in general and reading instruction in particular? How did they handle for example the increasing range of variation concerning knowledge and skills that goes together with increasing variation of age? With respect to reading the investigation also examined the content of reading instruction and the extent to which teachers took into account those factors that, according to reading research, are important for the acquisition of reading skills? Overall the research aimed to examine how the reading ability of the pupils developed during their first years at school. Six child schools were included in the study. The data collection extended over three years and contained field studies, interviews with the staff and reading tests with the pupils. Reading theories were used to analyse the form of the reading instruction and Basil Bernstein's theory of visible and invisible pedagogy was used to analyse pedagogical practice in its context. With one exception a visible pedagogy dominated in all the child schools. During lessons designated "my own work" the pupils were allowed to plan their work. This weak framing allowed the pupils to sort themselves into groups of more or less successful learners. In reading instruction, elements of two different models for instruction were combined, e.g. the whole language and the basal reading approach. My conclusion is that this combination is effective in a mixed-age group. Pupils at different competence levels benefit from different approaches. The reading comprehension of the child school pupils did not differ from the levels obtained with comparable pupils in national surveys. The test results, like the learning conditions varied between the schools. In my view the test results were not merely a consequence of the instruction, but also of other circumstances that interacted with the pedagogy.
|
|
| 14. |
|
|
| 15. |
- Ahlm, Clas, 1956-, et al.
(författare)
-
Central nervous system and ophthalmic involvement in nephropathia epidemica (European type of haemorrhagic fever with renal syndrome)
- 1998
-
Ingår i: Journal of Infection. - 0163-4453 .- 1532-2742. ; 36:2, s. 149-155
-
Tidskriftsartikel (refereegranskat)abstract
- Central nervous system (CNS) - related symptoms occur in haemorrhagic fever with renal syndrome (HFRS). To study the CNS and ophthalmic involvement in nephropathia epidemica (NE), the European type of HFRS, we included 26 patients in a prospective study. Most common CNS-related symptoms were headache (96%), insomnia (83%), vertigo (79%), nausea (79%), and vomiting (71%). Ophthalmic symptoms were reported by 82% of patients; 41% had photophobia and 50% had impaired vision. A transient loss of vision was recorded in one patient, who also had a generalized seizure. Minor white matter lesions were found in about half of the patients investigated with brain magnetic resonance imaging (MRI). Electroencephalography (EEG) showed severe alterations in only one patient, and slight and reversible patterns in another two patients. Neopterin, interleukin-6 and interferon-gamma levels in the cerebrospinal fluid (CSF) were elevated, which may indicate immune activation. However, we found no evidence of intrathecal NE virus replication. We conclude that CNS-related symptoms are common in NE, and transient ophthalmic involvement can be demonstrated in about half of the patients.
|
|
| 16. |
|
|
| 17. |
- Ahlm, Clas, 1956-
(författare)
-
Distribution of puumala virus in Sweden
- 1997
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Puumala virus, belonging to the genus hantavirus, is the causative agent of nephropathia epidemica (NE), a relatively mild form of hemorrhagic fever with renal syndrome. Puumala virus occurs endemically in Central and Northern Europe and Western Russia. In Sweden, NE is reported from the northern and central parts but virtually not at all from the southern part of the country. The bank vole (Clethrionomys glareolus) is the main reservoir of Puumala virus and humans are infected by inhalation of aerosolized animal secreta. In northern Sweden, the density of the bank vole population varies cyclically in intervals of 3-4 years and the incidence of NE shows a covariation.The prevalence of serum antibodies to hantaviruses in northern Sweden was studied in a stratified and randomly selected adult population sample comprising 1538 subjects. As expected, the prevalence increased with age. There was no difference between men and women, which was unexpected based on a male:female ratio of > 2:1 in clinical reports. By use of an immunofiuorescent assay, a seroprevalence of 5.4% and by a newly developed enzyme-linked immunosorbent assay (ELISA) with recombinant Puumala virus nucleocapsid protein as antigen, a prevalence of 8.9% was recorded. This is about or more than ten times higher than what would be calculated from clinical reports.By use of the ELISA, an occupational risk of acquisition of Puumala virus infection was demonstrated. Serum samples from 910 farmers and 663 referent subjects living in various rural parts of Sweden were tested. Among farmers from the Puumala virus-endemic northern and central parts of the country, the seroprevalence (12.9%) was higher (p=0.01) than in referents (6.8%). In the southern part of Sweden, only 2/459 persons had antibodies. Only a limited number of children with NE had been previously reported. In a separate study, 32 children with Puumala virus infection were identified and the clinical picture of NE in children was found to be similar to that of adult cases.Variations in the prevalence of Puumala virus in the bank vole population within an endemic region are not well known. Here, a higher mean rodent density and a higher prevalence of Puumala virus-specific serum antibodies were recorded in the vicinity of households afflicted with NE than in rural control areas. The data indicated that the risk of exposure locally within an endemic region may vary widely and tentatively suggested that a threshold density of bank voles might be necessary to achieve before effective spread of Puumala virus within the rodent population may occur.There is no firm evidence of the occurrence of Puumala virus among wild living animals other than rodents. A study of Swedish moose, an animal which is ecologically well characterized, was performed. Convincing evidence of past Puumala virus infection was found in 5/260 moose originating from Puumala virus-endemic areas but in none of 167 animals from nonendemic areas. Based on the low seroprevalence recorded, moose seemed to serve as endstage hosts rather than being active parts of the enzootic circle of transmission.In conclusion, the present investigations confirmed that the exposure to Puumala virus is geographically well restricted in Sweden. Seroprevalence studies indicated that only a minor proportion of individuals infected with Puumala virus are clinically reported, with a bias in favour of men. NE was confirmed to occur in children, with a clinical picture similar to that of adults. An occupational risk was defined for acquisition of Puumala virus infection. Studies in rodents suggested that there may be wide local variations within a limited area in the risk of exposure to Puumala virus. The studies validated the usefulness of a newly developed ELISA based on recombinant nucleocapsid peptides of hantaviruses and finally, methodological progress was reached when Puumala virus was, for the first time, successfully isolated from a Scandinavian patient.
|
|
| 18. |
- Ahlm, Clas, 1956-, et al.
(författare)
-
Health problems and self-medication among Swedish travellers.
- 1994
-
Ingår i: Scandinavian Journal of Infectious Diseases. - 0036-5548 .- 1651-1980. ; 26:6, s. 711-7
-
Tidskriftsartikel (refereegranskat)abstract
- 500 consecutive travellers seeking pre-travel health advice were issued a questionnaire before leaving Sweden to continuously record health problems and use of medication during travel. Of 442 subjects who turned in assessable questionnaires (232 male and 210 female, mean age 37 years), 81% travelled to areas at high risk for the acquisition of diarrhea. The mean duration of travel was 4 weeks. During travel 218 (49% at 95% CI 44.3 to 53.7%) of the travellers experienced some illness and 61 (14%) had symptoms of more than one illness. The mean duration of illness was 4.5 days, and 65 subjects (30% of ill travellers) were confined to bed for a mean duration of 2 days. The incidence of illness was significantly (p < 0.01) higher among travellers to high risk than to low risk areas (55% vs 26%), among young travellers than among elderly (65% vs 33%), and among those going on adventure tours compared with recreational tourists (74% vs 41%). Diarrhea was reported by 36% (95% CI 31.6 to 40.5%), and respiratory tract infection by 21% (95% CI 17.2 to 24.8%). Self-medication with one or several drugs was initiated by 163 (75%) travellers experiencing illness during travel. Thus, every second Swedish traveller to tropical and subtropical areas experienced some kind of travel-related, often incapacitating, health problem.
|
|
| 19. |
- Ahlm, Clas, 1956-, et al.
(författare)
-
High prevalence of hantavirus antibodies in bank voles (Clethrionomys glareolus) captured in the vicinity of households afflicted with nephropathia epidemica.
- 1997
-
Ingår i: American Journal of Tropical Medicine and Hygiene. - 0002-9637 .- 1476-1645. ; 56:6, s. 674-8
-
Tidskriftsartikel (refereegranskat)abstract
- Puumala virus, the causative agent of nephropathia epidemica (NE), occurs endemically in Europe and is spread mainly by the bank vole (Clethrionomys glareolus). In the vicinity of each of four households afflicted with NE, we studied rodents with regard to population density and prevalence of Puumala virus-specific antibodies. For each case area, a control area was randomly selected 10 km away, without regard to the presence of human settlement. During 6,000 trap nights, 328 rodents were caught, of which 299 were C. glareolus. The mean rodent densities of case and control areas were 6.6 and 3.7 animals per 100 trap nights (P < 0.001). The prevalence of serum antibodies was 15.9% in case areas compared with 5.6% in control areas (P < 0.05). In three of the case areas, where NE had occurred 3-10 weeks before trapping, the rodent density and seroprevalence were much higher than in the fourth area, where NE occurred 38 weeks before trapping. In conclusion, C. glareolus seropositive for Puumala virus occurred more frequently near households afflicted with NE than in control areas 10 km away.
|
|
| 20. |
|
|
