Hampakalk - En jämförelsestudie med avseende på brandegenskaper

Lime-hemp concrete is an old insulation material, made out of hemp shiv and lime, making its way back onto the market. This thesis focuses on the usage of lime-hemp as an alternative insulation material for restoration of older wooden buildings in the town of Visby in Gotland, Sweden. The aim of this report is to investigate fire resistance properties of lime-hemp concrete and to compare it to other insulation materials in this regard. The materials compared were: lime-hemp concrete, wood fiber insulation, flax insulation, EPS (expanded polystyrene) and stone wool insulation. Two experimental tests were conducted on each material, where samples of 10x10x5 cm3 were put in a cone calorimeter and radiated for 30 minutes with heat measuring 10 and 20 kW/m2. The results showed lime-hemp having the lowest temperature profile through the material, out of the tested materials. The mass loss of the material was higher than EPS and stone wool and lower then wood fiber and flax insulation, the latter of which started burning at 20 kW/m2. Most of the mass loss is assumed to be attributed to the evaporation of water

Undervisningsmetoders inverkan på elevers attityder till matematikundervisningen

I detta arbete har det undersökts vilka undervisningsmetoder lärare kan använda för att motivera gymnasieelever som har en negativ attityd till matematikundervisningen. Det står tydligt i läroplanen att läraren ska arbeta för att stärka elevers vilja att lära, det är därför relevant för lärarprofessionen att ta reda på hur lärarna ska göra detta rent praktiskt. För att finna relevant information har databassökningar genomförts. Resultatet av sökningarna kunde delas in i fem kategorier: lärarens förhållningssätt till elever, elevcentrerad undervisning, grupparbete, matematik i ett sammanhang och klassrumsklimatet. Detta framkom av litteraturen som de främsta faktorer i undervisningen som påverkar elevers attityder

Living with ALS : a literature review

Bakgrund: Amyotrofisk lateralskleros är en neurologisk sjukdom som i Sverige drabbar cirka 200 personer varje år. Sjukdomen är progressiv och gör att den drabbade personen förlorar kroppsliga funktioner och avlider oftast inom fem år. Att arbeta med personer som har en dödlig sjukdom kräver inte bara kunskap om sjukdomen utan också om hur personer upplever att leva med sjukdomen. Syfte: Syftet var att beskriva personers upplevelser av att leva med Amyotrofisk lateralskleros. Metod: En allmän litteraturstudie baserad på nio vetenskapliga artiklar genomfördes. Analysen gjordes genom en manifest innehållsanalys. Resultat: Fem kategorier presenterar upplevelserna av att leva med ALS. Dessa benämns En kropp i förändring, Relationer till andra påverkas, Hopp & hopplöshet, Kontroll & kontrollförlust samt Existensen utmanas. Slutsats: Personer som lever med ALS upplever ofta negativa känslor vilket påverkade deras livskvalitet i negativ riktning. Det uppmärksammades i mindre utsträckning även positiva känslor i samband med sjukdomen. För att kunna tillgodose en tillfredställande vård med grund i de individuella upplevelserna finns det behov av mer forskning inom ämnet. Genom mer kunskap om hur sjukdomen upplevs ökar förutsättningarna för personal att möta dem i deras individuella behov och därmed kan individens välbefinnande under sjukdomsförloppet öka.Background: Amyotrophic lateral sclerosis is a neurological disorder and in Sweden it affects about 200 people each year. The disease is progressive and makes the affected person lose bodily functions and usually dies within five years. Working with people who have a terminal illness requires not only knowledge of the disease, but also about how people experience living with the disease. Objective: The objective was to describe people's experiences of living with Amyotrophic lateral sclerosis. Method: A general literature review based on nine scientific articles was conducted. The analysis was done by a manifest content analysis. Results: Five categories presents the experiences of living with ALS. These are called A body in change, Relationships with others are affected, Hope & hopelessness, Control & loss of control and The existence challenged. Conclusion: People living with ALS often experience negative emotions which affected their quality of lifein a negative direction. Positive emotions associated with the disease was noticed in a lesser extent. To be able to reach a satisfactory care with basis in the individual experiences, there is a need for more research on the subject. More knowledge about how the disease is experienced increase the chances for the staff to meet them in their individual needsand therefore, the individual's well-being during the disease progression increase

Adenosine inhibition of the regeneration in vitro of adult frog sciatic sensory axons

The sensory axons of the adult frog sciatic nerve have earlier been shown to regenerate in vitro. If a local test crush is made at the initiation of culturing, regeneration starts after 3.4 days and proceeds at a rate of about 0.8-0.9 mm/day for several days. In the present experiments regeneration was inhibited by adenosine in a reversible and dose-dependent fashion. Similarly, both an adenosine analogue, 2-chloroadenosine (2-CA), and a non-hydrolyzable ATP analogue, AMP-PNP, reduced the outgrowth of sensory axons. The effect of adenosine was partially antagonized by theophylline at a critical concentration. Using a compartmental system, it could clearly be shown that adenosine exerted its effects at the outgrowth region. Adenosine, 2-CA, and AMP-PNP were also found to inhibit the proliferation of Schwann cells in the regenerating nerve. Various experiments showed that the latter can not explain the outgrowth inhibitory effects, which could be mediated by adenosine receptors associated with the elongating axons

Regeneration in vitro of the adult frog sciatic sensory axons

The adult frog sciatic nerve offers several advantages as an in vitro model to study nerve regeneration. The nerve with the attached dorsal root ganglia can easily be isolated and incubated in a culture medium for several days. If the nerve is subjected to a crush immediately after dissection there is a delay of 3.4 days after which the sensory axons start to regenerate into the distal nerve stump at a constant rate of about 1.1 mm · day−1 in serum-containing and 1.0 mm · day−1 in serum-free medium. Serum-free cultures may be used in future studies to examine the effect of various neurotrophic factors. The existence of an accurate method for examining the outgrowth distance, based on axonal transport of labelled proteins, contributes to the attractiveness of the model. A compartmental culture system permits separate exposure of the ganglia and the nerve to different agents. Taking advantage of this, pharmacological studies suggest that Schwann cells produce signals, dependent on newly transcribed RNA, which transform the preparation into a growth state. The present model system offers favourable conditions to learn more about the early events and also the subsequent steps of the regeneration process

Time‐dependent effects of insulin on Schwann cell proliferation in the in vitro regenerating adult frog sciatic nerve

The present study showed that insulin (0.01 μg/ml, ≈︂ 2 nM) inhibited [3H]‐thymidine incorporation in support cells, most likely Schwann cells, of the cultured frog sciatic nerve. A 25–35% inhibition took place in regenerating nerve preparations as well as in preparations devoid of neuronal protein synthesis, i.e., in isolated 5 mm nerve segments and in gangliectomized nerves, suggesting that the effect was direct and not mediated via the neuronal cells. The inhibition by insulin was time‐dependent in that an effect was seen after 4 days but not at shorter or at longer periods of culturing. In separate experiments biotinylated insulin was shown to be taken up by Schwann cells in the regenerating nerve. Addition of serum increased the [3H]‐thymidine incorporation severalfold and abolished the inhibitory action of insulin. Our results suggest that insulin, at a certain stage of the regeneration programme, exerts a direct, inhibitory effect on the proliferation of the Schwann cells in the cultured frog sciatic nerve. © 1993 Wiley‐Liss, Inc

Growth cones of regenerating adult sciatic sensory axons release axonally transported proteins

Labelled, rapidly transported axonal proteins were shown to be released frog adult frog sciatic sensory neurons, regenerating in vitro after a crush injury. The spatial distribution of the transported, released proteins could accurately be resolved by culturing the nerve on nitrocellulose paper, which trapped the released proteins. The release was located to the crush and to the entire outgrowth region. When regeneration was inhibited by adenosine, the release was limited to the crush site, implying that the release was linked to the growing axons. Other experiments suggested that the release emanated from growth cones. Furthermore, two-dimensional electrophoretical analysis of both fast axonally transported and of released proteins showed that the represented a selection of the transported protein species

Insulin and IGF-II, but not IGF-I, stimulate the in vitro regeneration of adult frog sciatic sensory axons

We used the in vitro regenerating frog sciatic nerve to look for effects of insulin and insulin-like growth factors I and II (IGF-I, IGF-II) on regeneration of sensory axons and on injury induced support cell proliferation in the outgrowth region. In nerves cultured for 11 days, a physiological dose (10 ng/ml, ≈ nM) of insulin or IGF-II increased ganglionic protein synthesis (by 20% and 50%, respectively) as well as the level of newly formed, radiolabelled axonal material distal to a crush injury (both by 80%), compared to untreated, paired controls. In addition, insulin increased the outgrowth distance of the furthest regenerating sensory axons by 10%. The preparation was particularly sensitive to insulin during the first 5 days of culturing. Furthermore, both insulin and IGF-II were found to inhibit proliferation of support cells in the outgrowth region in a manner suggesting effects via their individual receptors. The inhibition, about 30%, was observable after 4 but not 11 days in culture. It is not clear if this reflects a stimulated differentiation of some cells. By contrast, IGF-I lacked effects on both regeneration and proliferation. In conclusion, the results suggest that insulin and IGF-II are involved in the regulation of peripheral nerve regeneration