| 1. |
- Ahlberg, Erik, et al.
(författare)
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"Vi klimatforskare stödjer Greta och skolungdomarna"
- 2019
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Ingår i: Dagens nyheter (DN debatt). - 1101-2447.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- DN DEBATT 15/3. Sedan industrialiseringens början har vi använt omkring fyra femtedelar av den mängd fossilt kol som får förbrännas för att vi ska klara Parisavtalet. Vi har bara en femtedel kvar och det är bråttom att kraftigt reducera utsläppen. Det har Greta Thunberg och de strejkande ungdomarna förstått. Därför stödjer vi deras krav, skriver 270 klimatforskare.
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| 2. |
- Moberg, Christina, et al.
(författare)
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De unga gör helt rätt när de stämmer staten
- 2022
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Ingår i: Aftonbladet. - 1103-9000.
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- 1 620 forskare och lärare i forskarvärlden: Vi ställer oss bakom Auroras klimatkrav
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| 3. |
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| 4. |
- Aqvist, Johan, et al.
(författare)
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Bridging the gap between ribosome structure and biochemistry by mechanistic computations
- 2012
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Ingår i: Current opinion in structural biology. - : Elsevier BV. - 0959-440X .- 1879-033X. ; 22:6, s. 815-823
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Tidskriftsartikel (refereegranskat)abstract
- The wealth of structural and biochemical data now available for protein synthesis on the ribosome presents major new challenges for computational biochemistry. Apart from technical difficulties in modeling ribosome systems, the complexity of the overall translation cycle with a multitude of different kinetic steps presents a formidable problem for computational efforts where we have only seen the beginning. However, a range of methodologies including molecular dynamics simulations, free energy calculations, molecular docking and quantum chemical approaches have already been put to work with promising results. In particular, the combined efforts of structural biology, biochemistry, kinetics and computational modeling can lead towards a quantitative structure-based description of translation.
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| 5. |
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| 7. |
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| 8. |
- Haars, Jonathan, et al.
(författare)
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Prevalence of SARS-CoV-2 Omicron Sublineages and Spike Protein Mutations Conferring Resistance against Monoclonal Antibodies in a Swedish Cohort during 2022–2023
- 2023
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Ingår i: Microorganisms. - : MDPI. - 2076-2607. ; 11:10
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Tidskriftsartikel (refereegranskat)abstract
- Monoclonal antibodies (mAbs) are an important treatment option for COVID-19 caused by SARS-CoV-2, especially in immunosuppressed patients. However, this treatment option can become ineffective due to mutations in the SARS-CoV-2 genome, mainly in the receptor binding domain (RBD) of the spike (S) protein. In the present study, 7950 SARS-CoV-2 positive samples from the Uppsala and Örebro regions of central Sweden, collected between March 2022 and May 2023, were whole-genome sequenced using amplicon-based sequencing methods on Oxford Nanopore GridION, Illumina MiSeq, Illumina HiSeq, or MGI DNBSEQ-G400 instruments. Pango lineages were determined and all single nucleotide polymorphism (SNP) mutations that occurred in these samples were identified. We found that the dominant sublineages changed over time, and mutations conferring resistance to currently available mAbs became common. Notable ones are R346T and K444T mutations in the RBD that confer significant resistance against tixagevimab and cilgavimab mAbs. Further, mutations conferring a high-fold resistance to bebtelovimab, such as the K444T and V445P mutations, were also observed in the samples. This study highlights that resistance mutations have over time rendered currently available mAbs ineffective against SARS-CoV-2 in most patients. Therefore, there is a need for continued surveillance of resistance mutations and the development of new mAbs that target more conserved regions of the RBD.
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| 9. |
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| 10. |
- Israelsson, Johan, et al.
(författare)
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Health status and psychological distress among in-hospital cardiac arrest survivors in relation to gender
- 2017
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Ingår i: Resuscitation. - : Elsevier. - 0300-9572 .- 1873-1570. ; 114, s. 27-33
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Tidskriftsartikel (refereegranskat)abstract
- AIM: To describe health status and psychological distress among in-hospital cardiac arrest (IHCA) survivors in relation to gender.METHODS: This national register study consists of data from follow-up registration of IHCA survivors 3-6 months post cardiac arrest (CA) in Sweden. A questionnaire was sent to the survivors, including measurements of health status (EQ-5D-5L) and psychological distress (HADS).RESULTS: Between 2013 and 2015, 594 IHCA survivors were included in the study. The median values for EQ-5D-5L index and EQ VAS among survivors were 0.78 (q1-q3=0.67-0.86) and 70 (q1-q3=50-80) respectively. The values were significantly lower (p<0.001) in women compared to men. In addition, women reported more problems than men in all dimensions of EQ-5D-5L, except self-care. A majority of the respondents reported no problems with anxiety (85.4%) and/or symptoms of depression (87.0%). Women reported significantly more problems with anxiety (p<0.001) and symptoms of depression (p<0.001) compared to men. Gender was significantly associated with poorer health status and more psychological distress. No interaction effects for gender and age were found.CONCLUSIONS: Although the majority of survivors reported acceptable health status and no psychological distress, a substantial proportion reported severe problems. Women reported worse health status and more psychological distress compared to men. Therefore, a higher proportion of women may be in need of support. Health care professionals should make efforts to identify health problems among survivors and offer individualised support when needed.
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| 11. |
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| 12. |
- Jakobsson, Martin, 1966-, et al.
(författare)
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An Arctic Ocean ice shelf during MIS 6 constrained by new geophysical and geological data
- 2010
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Ingår i: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791 .- 1873-457X. ; 29:25-26, s. 3505-3517
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Tidskriftsartikel (refereegranskat)abstract
- The hypothesis of floating ice shelves covering the Arctic Ocean during glacial periods was developed in the 1970s. In its most extreme form, this theory involved a 1000 m thick continuous ice shelf covering the Arctic Ocean during Quaternary glacial maxima including the Last Glacial Maximum (LGM). While recent observations clearly demonstrate deep ice grounding events in the central Arctic Ocean, the ice shelf hypothesis has been difficult to evaluate due to a lack of information from key areas with severe sea ice conditions. Here we present new data from previously inaccessible, unmapped areas that constrain the spatial extent and timing of marine ice sheets during past glacials. These data include multibeam swath bathymetry and subbottom profiles portraying glaciogenic features on the Chukchi Borderland, southern Lomonosov Ridge north of Greenland, Morris Jesup Rise, and Yermak Plateau. Sediment cores from the mapped areas provide age constraints on the glaciogenic features. Combining these new geophysical and geological data with earlier results suggests that an especially extensive marine ice sheet complex, including an ice shelf, existed in the Amerasian Arctic Ocean during Marine Isotope Stage (MIS) 6. From a conceptual oceanographic model we speculate that the cold halocline of the Polar Surface Water may have extended to deeper water depths during MIS 6 inhibiting the warm Atlantic water from reaching the Amerasian Arctic Ocean and, thus, creating favorable conditions for ice shelf development. The hypothesis of a continuous 1000 m thick ice shelf is rejected because our mapping results show that several areas in the central Arctic Ocean substantially shallower than 1000 m water depth are free from glacial influence on the seafloor.
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| 13. |
- Kumarathunge, Dushan P., et al.
(författare)
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Acclimation and adaptation components of the temperature dependence of plant photosynthesis at the global scale
- 2019
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Ingår i: New Phytologist. - : John Wiley & Sons. - 0028-646X .- 1469-8137. ; 222:2, s. 768-784
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Tidskriftsartikel (refereegranskat)abstract
- The temperature response of photosynthesis is one of the key factors determining predicted responses to warming in global vegetation models (GVMs). The response may vary geographically, owing to genetic adaptation to climate, and temporally, as a result of acclimation to changes in ambient temperature. Our goal was to develop a robust quantitative global model representing acclimation and adaptation of photosynthetic temperature responses.We quantified and modelled key mechanisms responsible for photosynthetic temperature acclimation and adaptation using a global dataset of photosynthetic CO2 response curves, including data from 141 C3 species from tropical rainforest to Arctic tundra. We separated temperature acclimation and adaptation processes by considering seasonal and common-garden datasets, respectively.The observed global variation in the temperature optimum of photosynthesis was primarily explained by biochemical limitations to photosynthesis, rather than stomatal conductance or respiration. We found acclimation to growth temperature to be a stronger driver of this variation than adaptation to temperature at climate of origin.We developed a summary model to represent photosynthetic temperature responses and showed that it predicted the observed global variation in optimal temperatures with high accuracy. This novel algorithm should enable improved prediction of the function of global ecosystems in a warming climate.
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| 14. |
- Lundberg, Johan, et al.
(författare)
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Direct evidence of active sympathetic vasodilatation in the skin of the human foot
- 1989
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Ingår i: Journal of Physiology. - 1469-7793. ; 417, s. 437-446
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Tidskriftsartikel (refereegranskat)abstract
- 1. During operative aorto-femoral vascular reconstructions on sixteen patients, the sympathetic chain was stimulated electrically between the L2 and L4 ganglia while blood flow was monitored by laser doppler flowmeters from the skin on the sole of the foot and the ankle and by an electromagnetic flowmeter from the deep femoral artery. Epidural anaesthesia to at least the T6 level was used which excluded reflex effects. 2. Stimulation (10 Hz) at 1-12 mA current strengths for 30 s evoked both reductions and increases of blood flow in glabrous and hairy skin. Initial short-lasting flow increases (durations 9-19 s) followed by sustained decreases were common: sometimes there were sustained flow increases at low and decreases at high current strengths. 3. In the deep femoral artery (supplying predominantly muscle) only flow reductions were evoked. 4. The results provide evidence for sympathetically mediated vasodilatation in the skin of the human foot whereas leg muscles may be supplied by vasoconstrictor nerves only.
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| 15. |
- Meurling, Lisbet, et al.
(författare)
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Comparison of high- and low equipment fidelity during paediatric simulation team training : a case control study
- 2014
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Ingår i: BMC Medical Education. - : Springer Science and Business Media LLC. - 1472-6920. ; 14, s. 221-
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Tidskriftsartikel (refereegranskat)abstract
- Background: High-fidelity patient simulators in team training are becoming popular, though research showing benefits of the training process compared to low-fidelity models is rare. We explored in situ training for paediatric teams in an emergency department using a low-fidelity model (plastic doll) and a high-fidelity paediatric simulator, keeping other contextual factors constant. The goal was to study differences in trainees' and trainers' performance along with their individual experiences, during in situ training, using either a low-fidelity model or a high-fidelity paediatric simulator.Methods: During a two-year period, teams involved in paediatric emergency care were trained in groups of five to nine. Each team performed one video-recorded paediatric emergency scenario. A case control study was undertaken in which 34 teams used either a low-fidelity model (n = 17) or a high-fidelity paediatric simulator (n = 17). The teams' clinical performances during the scenarios were measured as the time elapsed to prescribe as well as deliver oxygen. The trainers were monitored regarding frequency of their interventions. We also registered trainees' and trainers' mental strain and flow experience.Results: Of 225 trainees' occasions during 34 sessions, 34 trainer questionnaires, 163 trainee questionnaires, and 28 videos, could be analyzed. Time to deliver oxygen was significantly longer (p = 0.014) when a high-fidelity simulator was used. The trainees' mental strain and flow did not differ between the two types of training. The frequency of trainers interventions was lower (p < 0.001) when trainees used a high-fidelity simulator; trainers' perceived mental strain was lower (< 0.001) and their flow experience higher (p = 0.004) when using high-fidelity simulator.Conclusions: Levels of equipment fidelity affect measurable performance variables in simulation-based team training, but trainee s' individual experiences are similar. We also note a reduction in the frequency of trainers' interventions in the scenarios as well as their mental strain, when trainees used a high-fidelity simulator.
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| 16. |
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| 17. |
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| 18. |
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| 19. |
- Söderberg, Johan, 1980-, et al.
(författare)
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Haemolysis index : an estimate of preanalytical quality in primary health care!
- 2009
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Ingår i: Clinical Chemistry and Laboratory Medicine. - 1434-6621 .- 1437-4331. ; 47:8, s. 940-944
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Tidskriftsartikel (refereegranskat)abstract
- Background: Haemolysis is usually caused by inadequate specimen collection or preanalytical handling, and is suggested to be a suitable indicator of preanalytical quality. We investigated the prevalence of detectable haemolysis in all routine venous blood samples to identify differences in preanalytical quality.Methods: Haemolysis index (HI) values were obtained from a Vitros 5,1 in the routine clinical chemistry laboratory for samples collected in primary health care centres (PHCs), nursing homes, and a hospital emergency department (ED). Haemolysis was defined as a HI ≥ 15 (detection limit).Results: Samples from the PHC with the highest prevalence of haemolysis were 6.1 times (95% confidence interval (CI) 4.0-9.2) more often haemolysed compared to the centre with the lowest prevalence. Of the samples collected in primary health care, 10.4% were haemolysed compared to 31.1% in the ED (p< 0.001). A notable difference in haemolysed samples was found between the ED section staffed by emergency medicine physicians and the section staffed by primary health care physicians (34.8% vs. 11.3%, p<0.001).Conclusions: The significant variation in haemolysis indices among the investigated units is likely to reflect varying preanalytical conditions. The HI is a valuable tool for estimation and follow-up of preanalytical quality in primary health care.
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| 20. |
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| 21. |
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| 22. |
- Wallin, Georg, 1686-1760
(författare)
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Vrbs antiqva rvit, mvltos dominata per annos, Virgil. Æn. II. Hoc est, Sigtvna stans et cadens, cujus aetatem primam, consensu ampliss. facult. philos. praeside Georgio Wallin, fil. ... publico bonorum examini submittit Johannes Marck, Vplandus, in aud. Gust. maj. die 6. Decemb. an ch. clɔ dcc xxix, horis ante meridiem solitis
- 1729
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)
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| 24. |
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| 25. |
- Wallin, Johan, et al.
(författare)
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Digitala lärresurser I matematikundervisningen, delrapport skola : Systematisk översikt 2017:02
- 2017
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Denna systematiska översikt sammanställer forskning om digitala lärresurser för att utveckla barns och elevers kunskaper i matematik. Forskningen spänner över förskolan till och med gymnasieskolan och anknyter specifikt till matematikundervisningen. I denna rapport redovisas översiktens resultat för grund-och gymnasieskolan.De digitala lärresurser som studeras erbjuder alla en interaktivitet. Det betyder att eleverna är aktiva i relation till lärresursen i själva undervisningssituationen.De frågor som besvaras i rapporten är:Vilka effekter har matematikundervisning med digitala lärresurser på elevers kunskaper i matematik?Vad kan förklara om en matematikundervisning med digitala lärre- surser har effekt eller inte på elevers kunskaper i matematik?Översikten har sin bakgrund bland annat i lärares frågor om huruvida undervisning med hjälp av digitala lärresurser kan påverka elevers kunskapsutveckling.Digitala lärresurser i grund- och gymnasieskolanDet vetenskapliga underlaget består av 75 studier. Endast två studier är gjorda i Sverige, men alla studier berör ett matematikinnehåll som är relevant för den svenska skolan. Upp till och med årskurs 6 dominerar digitala lärresurser med fokus på området tal och taluppfattning, men det finns studier som behandlar annat innehåll, till exempel algebra eller geometri. I högre årskurser är det vanligaste innehållet algebra samt samband och förändring.När det gäller matematiska förmågor är det många digitala lärresurser som fokuserar på begrepps-och proceduranvändning, men även bland dem kan ofta också aktiviteter som involverar andra förmågor adresseras, såsom problemlösnings-och resonemangsförmåga.Vi har kunnat identifiera fem olika huvudkategorier av digitala lärresurser för matematikundervisning i grund-och gymnasieskolan:Uppgifter: lärresurser som levererar matematikuppgifter tillsammans med vägledning eller individanpassning. Uppgifterna och vägledningen regleras i många fall utifrån hur användaren presterar.Objekt: lärresurser med vilka matematik och matematiska objekt, till exempel geometriska former, kan representeras genom att utnyttja det digitala mediet.Spel: lärresurser som utnyttjar spelmekanismer såsom uppdrag, utmaningar, belöningar och tävlingsmoment för att förmedla ett ämnesinnehåll. Spelkaraktäriseras ofta av lekfullt utforskande inom ramen för en berättelse.––Verktyg: lärresurser som har tagits fram i ett annat syfte än för att bedriva undervisning, men som kan användas i matematikundervisningssammanhang, till exempel ett kalkyl-eller grafritande program.––Kurspaket: lärresurser av ett mer omfattande slag som kan innehålla flera funktioner och beröra många matematikområden. Ofta är kurspaketen tänkta att användas som ett komplement under en längre tid, till exempel under en hel årskurs. I vissa fall handlar det om undervisningspaket som består av olika kombinationer av digitala lärresurser och tryckt material samt lektionsupplägg, lärarhandlingar och kompetensutveckling för lärarna.Kategorierna är inte exakta och det finns överlapp mellan dem. Vid kategoriseringen strävade vi efter att hitta en huvudmekanism för lärresursen i fråga.Undervisning med digitala lärresurser kan ha positiva effekterGenomgången visar tydligt att det går att konstruera digitala lärresurser som kan användas för att utveckla många olika matematiska förmågor, i synnerhet om de används i en i övrigt rik undervisningsmiljö. Men det går inte att dra slutsatsen att en lika effektiv undervisning inte skulle kunna utformas på andra sätt, utan digitala lärresurser.Gynnsamt med ett tydligt fokus på tröskelbegreppDet är positivt för elevers kunskapsutveckling om undervisning med digitala lärresurser har ett avgränsat matematikinnehåll som eleverna kan arbeta med på ett fokuserat sätt. En stor del av forskningen behandlar sådana arbetssätt och det finns flera tänkbara skäl till att de i många fall ger goda resultat. Dels kan det vara lättare att konstruera bra digitala lärresurser om man begränsar sig till ett mindre omfattande matematikinnehåll, dels kan det vara lättare för både lärare och elever att lära sig att använda den sortens lärresurser. Genomgången tyder vidare på att det av forskningstekniska skäl är lättare att uppnå tydliga effekter vid den här sortens upplägg.När ett relativt smalt matematikinnehåll behandlas är det i allmänhet valt på ett genomtänkt sätt, exempelvis kan det handla om steg i matematikutvecklingen som är vedertaget problematiska. Ofta talar man om så kallade tröskelbegrepp – matematiska begrepp som eleverna behöver förstå för att kunna utvecklas vidare inom ett område. Exempel på tröskelbegrepp som berörs i underlaget är bråk och funktioner.Varierade sätt att uppleva, erfara och kommunicera matematikDet förefaller vara positivt för elevers kunskapsutveckling om de digitala lärresurserna möjliggör att eleverna kan uppleva och urskilja matematiska begrepp och processer visuellt och dynamiskt. Det kan exempelvis uppnås genom att använda digitala geometriska objekt för att ge elever rika och varierade upplevelser av geometriska egenskaper. Det verkar vidare vara bra om lärresurserna är konstruerade på ett sätt som uppmuntrar till att elever samtalar om matematikupplevelserna med varandra och med lärare. Det kan åstadkommas såväl med digitala lärresurser för samarbetsinriktade arbetssätt som med digitala lärresurser för självständigt arbete.Med undantag för kurspaket kan de flesta typer av digitala lärresurser fungera braDigitala kurspaket har i allmänhet studerats i stora elevgrupper under lång tid, till exempel en hel årskurs. Man kan säga att dessa studier utgör en slags motpol till studier med ett avgränsat matematikinnehåll. Även resultatmässigt är kontrasten stor; kurspaketen tycks i de allra flesta fall inte innebära några betydelsefulla vinster för kunskapsutvecklingen. Möjligen är kurspaketens enskilda delar inte lika bra som lärresurser med ett mer avgränsat ämnesinnehåll, eller så innefattar de både gynnsamma och ogynnsamma enskilda delar som medför att effekterna tar ut varandra.En nackdel med studierna av digitala kurspaket är att det kan vara svårt att säkerställa i vilken utsträckning lärresurserna verkligen har använts så som det var tänkt. Samtidigt är det en fördel att studierna avspeglar vad som kan förväntas när omfattande digitala lärresurser används under lång tid i stora grupper. En tänkbar bidragande förklaring till att kurspaketen vanligen innebär små vinster – om några – är att det kan vara en större utmaning att förändra matematikundervisningen så att den generellt tar stöd i digitala lärresurser.Med undantag för kurspaketen har vi inte funnit stöd för att någon kategori av digitala lärresurser sticker ut när det gäller effekter på elevers matematikkunskaper. Det går att nå goda resultat med såväl uppgifter och objekt som spel och verktyg. Digitala verktyg har dock undersökts i endast två studier, båda på gymnasienivå. Det är i sig ett viktigt resultat att så få studier behandlar digitala verktyg i matematikundervisningen.Lärarens roll och arbete är centraltLärarens roll och arbete kan skilja sig beroende på utformningen av och syftet med en viss digital lärresurs. Medan vissa lärresurser är tänkta att i huvudsak erbjuda eleverna självständiga matematikaktiviteter, förutsätter andra att läraren själv hanterar den digitala lärresursen. Genomgången visar att det går att nå bra effekter på elevernas matematikkunskaper i båda fallen.Digitala lärresurser för självständigt arbete kan vara ett kompletterande stöd i undervisningen och på så sätt möjliggöra att lärare kan ägna mer tid och kraft åt andra aspekter av undervisningen. Det gör att resultatet blir mer beroende av lärresursen i sig, snarare än på interaktionen med övrig undervisning. Om lärresurserna erbjuder individanpassad vägledning kan det skapa särskilt goda förutsättningar för elevernas kunskapsutveckling. Men även när digitala lärresurser för självständigt arbete används verkar det vara särskilt gynnsamt om de används på ett integrerat sätt tillsammans med annan undervisning. Det är helt jämförbart med hur andra resurser för lärande i allmänhet kan användas. Exempelvis kan en digital lärresurs användas för att ge eleverna vissa typer av erfarenheter som sedan också behandlas inom den lärarledda undervisningen. Digitala lärresurser för självständigt arbete är vanligare i årskurser till och med mellanstadiet.Arbetssätt med digitala lärresurser som innebär en hög grad av aktiv lärarmedverkan eller som är tekniskt komplexa kräver oftast att lärarna först får möjlighet att utbilda sig i hur lärresurserna fungerar och vad som kan göras med stöd av dem. I dessa fall behöver man beakta länken mellan lärresurserna, undervisningens upplägg i övrigt och innehållet i kompetensutvecklingen. Det är tänkbart att de digitala lärresurser som i sig kräver en högre lärarinvolvering också ger bra förutsättningar för att skapa en sådan länkning. Samtidigt krävs då också mer av läraren. För den här sortens lärresurser blir det avgörande för resultatet vad läraren själv väljer att göra med lärresurserna tillsammans med sina elever.Urval av forskningAv nära 10 000 publikationer som identifierades i litteratursökningen har vi gått igenom drygt 700 studier i fulltext. Av dessa bedömdes totalt 85 studier kunna bidra till att besvara den systematiska översiktens frågor, varav 75 avser grund-och gymnasieskolan och 10 avser förskolan. I denna rapport redovisas resultaten från de 75 studier som avser grund-och gymnasieskolan.Alla studierna är kontrollerade experime
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| 26. |
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| 27. |
- Wallin, Kjell, et al.
(författare)
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Skattning av antalet kornknarrar på Öland 2008
- 2008
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Rapporten redovisar resultatet av en inventering vars syfte var att beräkna det totala antalet spelande kornknarrar på Öland och att beskriva de spelande hanarnas uppehållsmiljö. Inventeringen genomfördes med stratifierad stickprovtagning av 300 provpunkter jämnt fördelade över hela Öland under perioden maj – juli 2008, där varje punkt besöktes minst två gånger. Bandspelare som spelade upp kornknarrens läte användes för att öka chansen att upptäcka kornknarr. Metoden innebar dock ingen större förbättring. Som metod för att beräkna antalet spelande hanar har avståndsinventering använts från utvalda punkter. Bestämning av kornknarrarnas position har gjorts genom ”triangulering”. Skattningen av det maximala antalet spelande kornknarrar är 206 stycken. Genom skillnaden i uppträdande och antal, mellan första och andra inventeringstillfället, med 147 respektive 61 hanar, antyds att denna siffra kan vara en överskattning. En vidare diskussion av detta görs i rapporten. Geografiskt har kornknarren sin tyngdpunkt på mellersta och östra Öland. Uppehållsmiljön utgjordes till större delen av vall, betesmark och träda, vilket överensstämmer med tidigare gjorda studier på Öland. En jämförelse mellan rapporteringssystemet Svalan och skattning genom stickprovstagning visar på relativt stora skillnader i antal spelande kornknarrar, både tidsmässigt och geografiskt. Antalet kornknarrar som rapporteras till Svalan avtar från mitten av juni medan inventeringen visar att spelandet fortsätter med bibehållen intensitet in i juli. Observationerna från Svalan är koncentrerade till Ölands sydöstra delar medan observationerna från inventeringen är mer jämnt fördelade över ön, även om det finns en viss östlig förtätning.
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| 28. |
- Wallin, Mats, et al.
(författare)
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Fågelfaunan på Ölands sjömarker - inventeringar 1988-2008
- 2009
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Fåglarna på Ölands sjömarker har varit föremål för tre heltäckande inventeringar under de senaste 20 åren. Dessutom har delar av Öland inventerats årligen sedan 2003. För ändamålet är Ölands sjömarker indelade i 96 delområden. De artgrupper som inventerats är ”Vadare”, ”Änder, svanar och gäss” samt ”Tärnor och måsfågel”. Vid inventeringarna har antalet häckande par bedömts genom parräkning, boräkning och revirkartering. Vid sidan av fågelinventeringen har även hävden på sjömarkerna bedömts av inventerarna. Resultaten från inventeringarna har analyserats med syfte att beskriva enskilda fågelarters populationsutveckling på Öland som helhet och i respektive delområde. Dataunderlaget för hela perioden, 1988–2008, är ojämnt då fler inventeringar gjorts efter 2000. Därför har utvärderingen av arternas trender i första hand baserats på perioden 1998–2008. Utvecklingen är positiv för 14 arter medan sju arter visar en negativ utveckling. Skillnaden mellan artgrupperna är påtaglig. Änder, svanar och gäss ökar medan vadare i huvudsak uppvisar en negativ utveckling. Arter som ökar är silvertärna, skrattmås, sothöna, storskrake, vigg, grågås, gravand, knölsvan, skedand, snatterand, kricka, gräsand, större strandpipare och tofsvipa. Arter som minskar är ejder, kanadagås, strandskata, rödspov, ljungpipare, brushane och sydlig kärrsnäppa. Sett över hela perioden, 1988–2008, är förändringarna så stora att de med säkerhet kan utläsas för ytterligare några arter. Det är för havstrut och vitkindad gås som ökat medan silltrut, svärta, stjärtand, storspov och roskarl minskat. Arter som svärta, strandskata, sydlig kärrsnäppa, brushane, ljungpipare och rödspov ser ut att vara på väg att försvinna. Hävden på Ölands sjömarker har ökat under de senaste 20 åren. Relationen mellan hävden och antalet häckande vadare är svagt positiv och en stark hävd behöver inte betyda många vadare. Hävden är nödvändig i förvaltningen av av sjömarkerna men andra faktorer har förmodligen ett starkare inflytande på vadarnas populationsutveckling.
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| 29. |
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| 30. |
- Wallin, Olof, et al.
(författare)
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Preanalytical effects of pneumatic tube transport on routine haematology, coagulation parameters, platelet function and global coagulation
- 2009
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Ingår i: Clinical Chemistry and Laboratory Medicine. - 1434-6621 .- 1437-4331. ; 46:10, s. 1443-1449
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Tidskriftsartikel (refereegranskat)abstract
- Background: Pneumatic tube transport of blood samples reduces turnaround times and labour. However, the preanalytical effects on new clinical chemistry parameters and instruments are not fully known. The aim of this study was to evaluate the effect of pneumatic tube transport on haematology and coagulation parameters, including platelet function with PFA-100®, and global coagulation with a thromboelastograph.Methods: Paired venous blood samples from healthy volunteers were obtained before and after 1 week of treatment with acetylsalicylic acid. One sample was transported by pneumatic tube transport, while the other remained in the laboratory.Results: No preanalytical effect of pneumatic tube transport could be seen for most haematology and coagulation parameters, as well as analysis with PFA-100®. For the thromboelastographic analysis, time to clot formation was shorter (–16%, p=0.037) in the transported samples. Treatment with acetylsalicylic acid had no effect on the majority of the test results.Conclusions: Pneumatic tube transport does not introduce preanalytical errors when transporting samples for analysis of routine haematology, coagulation parameters and platelet function with the PFA-100®. We recommend manual transport of samples for analysis with thromboelastographic techniques.
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| 31. |
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| 32. |
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| 33. |
- Adalbjörnsson, Stefan Ingi, et al.
(författare)
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Estimating Periodicities in Symbolic Sequences Using Sparse Modeling
- 2015
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Ingår i: IEEE Transactions on Signal Processing. - 1053-587X. ; 63:8, s. 2142-2150
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Tidskriftsartikel (refereegranskat)abstract
- In this paper, we propose a method for estimating statistical periodicities in symbolic sequences. Different from other common approaches used for the estimation of periodicities of sequences of arbitrary, finite, symbol sets, that often map the symbolic sequence to a numerical representation, we here exploit a likelihood-based formulation in a sparse modeling framework to represent the periodic behavior of the sequence. The resulting criterion includes a restriction on the cardinality of the solution; two approximate solutions are suggested—one greedy and one using an iterative convex relaxation strategy to ease the cardinality restriction. The performance of the proposed methods are illustrated using both simulated and real DNA data, showing a notable performance gain as compared to other common estimators.
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| 34. |
- af Ekenstam, Angelica, et al.
(författare)
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Leaf respiration rates are increased by warm season as well as by elevated temperature treatment in Eucalyptus globulus
- 2014
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Ingår i: EGU General Assembly 2014, held 27 April - 2 May, 2014 in Vienna, Austria.
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Plant leaf respiration is one of the major CO2 fluxes between terrestrial biosphere and the atmosphere, and its responses to elevated CO2 and temperature thus have important implications for the carbon cycle and rate on ongoing climate change. Non-photorespiratory leaf respiration is reduced in light, Rlight, compared with the rate in the dark, Rdark. It is therefore important to consider both Rlight and Rdark when estimating the exchange of CO2 between the biosphere and the atmosphere, during current and future climates. This study was conducted at the Hawkesbury Forest Experiment, HFE, in Richmond, NSW, Australia. Trees of Tasmanian Blue Gum (Eucalyptus globulus Labill.) were exposed in whole tree chambers (WTC) to a complete factorial combination of ambient and elevated temperature and CO2 (+3 °C and +240 ppm CO2, respectively). The measurements of Rlight and Rdark were made in 2011 after 15 month exposure in the WTCs. The measurements were made in March (after the year’s hottest months) and October (after the coldest period). Rlight was determined at four temperatures ranging between 20 and 40 °C on attached leaves using a portable gas exchange system (LI-6400XT). Rdark was measured at 20-40 °C in October and at 25 °C in March. Rdark was measured after dark acclimation for at least 30 min and Rlight was determined from the intersection of the photosynthetic CO2 responses measured at three different light intensities using the Laisk metod. Trees grown in elevated temperature had a considerably higher Rdark (+53% across all measurement temperatures in October). However, Rlight did not respond significantly to either CO2 or temperature. In October, the Rlight to Rdark ratio indicated an overall light inhibition of respiration of 31% across all temperatures and in March the light inhibition was 22 % at 25 °C. The seasonal comparisons showed that both Rlight and Rdark were considerably higher after the warm compared to cold season, especially when measured at high temperature. These results points out the importance to account for Rlight as well as seasonal thermal respiratory acclimation when improving predictions of the carbon exchange between tree canopies and the atmosphere. If not taking light inhibition into account, leaf respiration is being overestimated and if not taking the seasonal acclimation into account the errors are potentially very large.
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| 35. |
- Alami, Jones, et al.
(författare)
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Phase tailoring of Ta thin films by highly ionized pulsed magnetron sputtering
- 2007
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Ingår i: Thin Solid Films. - : Elsevier. - 0040-6090 .- 1879-2731. ; 515:7-8, s. 3434-3438
-
Tidskriftsartikel (refereegranskat)abstract
- Ta thin films were grown on Si substrates at different inclination angles with respect to the sputter source using high power impulse magnetron sputtering (HIPIMS), an ionized physical vapor deposition technique. The ionization allowed for better control of the energy and directionality of the sputtered species, and consequently for improved properties of the deposited films. Depositions were made on Si substrates with the native oxide intact. The structure of the as deposited films was investigated using X-ray diffraction, while a four-point probe setup was used to measure the resistivity. A substrate bias process-window for growth of bcc-Ta was observed. However, the process-window position changed with changing inclination angles of the substrate. The formation of this low-resistivity bcc-phase could be understood in light of the high ion flux from the HIPIMS discharge.
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| 36. |
- Aloysie, Manishimwe, et al.
(författare)
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Warming Responses of Leaf Morphology Are Highly Variable among Tropical Tree Species
- 2022
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Ingår i: Forests. - : MDPI AG. - 1999-4907. ; 13:2
-
Tidskriftsartikel (refereegranskat)abstract
- Leaf morphological traits vary along climate gradients, but it is currently unclear to what extent this results from acclimation rather than adaptation. Knowing so is important for predicting the functioning of long-lived organisms, such as trees, in a rapidly changing climate. We investigated the leaf morphological warming responses of 18 tropical tree species with early (ES) abd late (LS) successional strategies, planted at three sites along an elevation gradient from 2400 m a.s.l. (15.2 °C mean temperature) to 1300 m a.s.l. (20.6 °C mean temperature) in Rwanda. Leaf size expressed as leaf area (LA) and leaf mass per area (LMA) decreased, while leaf width-to-length ratio (W/L) increased with warming, but only for one third to half of the species. While LA decreased in ES species, but mostly not in LS species, changes in LMA and leaf W/L were common in both successional groups. ES species had lower LMA and higher LA and leaf W/L compared to LS species. Values of LMA and LA of juvenile trees in this study were mostly similar to corresponding data on four mature tree species in another elevation-gradient study in Rwanda, indicating that our results are applicable also to mature forest trees. We conclude that leaf morphological responses to warming differ greatly between both successional groups and individual species, with potential consequences for species competitiveness and community composition in a warmer climate. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.
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| 37. |
- Angserud, Jenny, et al.
(författare)
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On a wear test for rock drill inserts
- 2013
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Ingår i: Wear. - : Elsevier BV. - 0043-1648 .- 1873-2577. ; 301:1-2, s. 109-115
-
Tidskriftsartikel (refereegranskat)abstract
- In this work wear of cemented carbide rock drill inserts is evaluated by using a rotating rock cylinder as counter surface. The influence on wear rate and degradation mechanisms from varying dry and wet conditions, cemented carbide grade, abrasive particle type and size as well as load is studied. The used abrasive media are alumina and silica.Test results show high repeatability and the three tested cemented carbide grades can be differentiated, even though their relative difference in sample hardness is modest. The loads used, 100–200 N, are sufficiently high to cause fracture and wear of the granite rock. The degraded microstructure of inserts tested under wet and dry conditions as well as with added silica particles is similar to field worn inserts. Hence, the same wear mechanisms occur and the test successfully mimics rock drill wear. Typical insert wear includes cracking and fragmentation of WC grains, depletion of Co binder phase and adhered material originating from the rock.Tests under dry conditions always cause less measured wear than tests under wet conditions.Addition of alumina particles, which are harder than the used cemented carbide samples, causes a significant wear rate increase but does not provide wear similar to rock drilling.
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| 38. |
- Arteta, Marianna Yanez, et al.
(författare)
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Successful reprogramming of cellular protein production through mRNA delivered by functionalized lipid nanoparticles
- 2018
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Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 115:15
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Tidskriftsartikel (refereegranskat)abstract
- © 2018 National Academy of Sciences. All Rights Reserved. The development of safe and efficacious gene vectors has limited greatly the potential for therapeutic treatments based on messenger RNA (mRNA). Lipid nanoparticles (LNPs) formed by an ionizable cationic lipid (here DLin-MC3-DMA), helper lipids (distearoylphos-phatidylcholine, DSPC, and cholesterol), and a poly(ethylene glycol) (PEG) lipid have been identified as very promising delivery ve ctors of short interfering RNA (siRNA) in different clinical phases; however, delivery of high-molecular weight RNA has been proven much more demanding. Herein we elucidate the structure of hEPO modified mRNA-containing LNPs of different sizes and show how structural differences affect transfection of human adipocytes and hepatocytes, two clinically relevant cell types. Employing small-angle scattering, we demonstrate that LNPs have a disordered inverse hexagonal internal structure with a characteristic distance around 6 nm in presence of mRNA, whereas LNPs containing no mRNA do not display this structure. Furthermore, using contrast variation small-angle neutron scattering, we show that one of the lipid components, DSPC, is localized mainly at the surface of mRNA-containing LNPs. By varying LNP size and surface composition we demonstrate that both size and structure have significant influence on intracellular protein production. As an example, in both human adipocytes and hepatocytes, protein expression levels for 130 nm LNPs can differ as much as 50-fold depending on their surface characteristics, likely due to a difference in the ability of LNP fusion with the early endosome membrane. We consider these discoveries to be fundamental and opening up new possibilities for rational design of synthetic nanoscopic vehicles for mRNA delivery.
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| 39. |
- Axelsson, Elin, et al.
(författare)
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Diagnostic Performance of Cerebrospinal Fluid Neurofilament Light Chain and Soluble Amyloid-β Protein Precursor β in the Subcortical Small Vessel Type of Dementia.
- 2023
-
Ingår i: Journal of Alzheimer's disease : JAD. - 1875-8908. ; 96:4, s. 1515-1528
-
Tidskriftsartikel (refereegranskat)abstract
- The subcortical small vessel type of dementia (SSVD) is a common subtype of vascular dementia, but there is a lack of disease-specific cerebrospinal fluid (CSF) biomarkers.We investigated whether CSF concentrations of neurofilament light chain (NFL), soluble amyloid-β protein precursor α (sAβPPα), sAβPPβ, and CSF/serum albumin ratio could separate SSVD from healthy controls, Alzheimer's disease (AD), and mixed dementia (combined AD and SSVD).This was a mono-center study of patients with SSVD (n=38), AD (n=121), mixed dementia (n=62), and controls (n=96). The CSF biomarkers were measured using immunoassays, and their independent contribution to the separation between groups were evaluated using the Wald test. Then, the area under the receiver operating characteristics curve (AUROC) and 95% confidence intervals (CIs) were calculated.Elevated neurofilament light chain (NFL) and decreased sAβPPβ independently separated SSVD from controls, and sAβPPβ also distinguished SSVD from AD and mixed dementia. The combination of NFL and sAβPPβ discriminated SSVD from controls with high accuracy (AUROC 0.903, 95% CI: 0.834-0.972). Additionally, sAβPPβ combined with the core AD biomarkers (amyloid-β42, total tau, and phosphorylated tau181) had a high ability to separate SSVD from AD (AUROC 0.886, 95% CI: 0.830-0.942) and mixed dementia (AUROC 0.903, 95% CI: 0.838-0.968).The high accuracy of NFL and sAβPPβ to separate SSVD from controls supports that SSVD is a specific diagnostic entity. Moreover, SSVD was distinguished from AD and mixed dementia using sAβPPβ in combination with the core AD biomarkers.
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| 40. |
- Axelsson, Elin, et al.
(författare)
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Patients with the Subcortical Small Vessel Type of Dementia Have Disturbed Cardiometabolic Risk Profile
- 2020
-
Ingår i: Journal of Alzheimers Disease. - : IOS Press. - 1387-2877 .- 1875-8908. ; 73:4, s. 1373-1383
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Population-based studies have shown that cardiometabolic status is associated with the amount of white matter hyperintensities (WMHs) on magnetic resonance imaging (MRI). However, little is known of cardiometabolic risk factors in the subcortical small vessel type of dementia (SSVD), in which WMHs are one of the most prominent manifestations. Objective: To determine whether the profile of cardiometabolic risk factors differed between SSVD, Alzheimer's disease (AD), mixed dementia (combined AD and SSVD), and healthy controls. Methods: This was a mono-center, cross-sectional study of SSVD (n = 40), AD (n = 113), mixed dementia (n = 62), and healthy controls (n = 94). In the statistical analyses, we adjusted for covariates using ANCOVA and binary logistic regression. Results: The prevalence of hypertension was increased in SSVD and mixed dementia (p < 0.001 and p < 0.05 versus controls, respectively). Diabetes was more prevalent in SSVD patients, and body mass index was lower in AD and mixed dementia, compared to the controls (all p < 0.05). Serum total cholesterol (TC) and low-density lipoprotein-cholesterol (LDL-C) were reduced in the SSVD group (both p < 0.05 versus control). These differences remained after adjustment for covariates. In the SSVD group, Trail Making Test A score correlated positively with systolic blood pressure, mean arterial pressure, and pulse pressure. Conclusion: All dementia groups had an altered cardiometabolic risk profile compared to the controls. The SSVD patients showed increased prevalence of hypertension and diabetes, and in line with previous population-based data, TC and LDL-C in serum were reduced.
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| 41. |
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| 42. |
- Bahnan, Wael, et al.
(författare)
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Spike-Dependent Opsonization Indicates Both Dose-Dependent Inhibition of Phagocytosis and That Non-Neutralizing Antibodies Can Confer Protection to SARS-CoV-2
- 2022
-
Ingår i: Frontiers in Immunology. - : Frontiers Media SA. - 1664-3224. ; 12
-
Tidskriftsartikel (refereegranskat)abstract
- Spike-specific antibodies are central to effective COVID19 immunity. Research efforts have focused on antibodies that neutralize the ACE2-Spike interaction but not on non-neutralizing antibodies. Antibody-dependent phagocytosis is an immune mechanism enhanced by opsonization, where typically, more bound antibodies trigger a stronger phagocyte response. Here, we show that Spike-specific antibodies, dependent on concentration, can either enhance or reduce Spike-bead phagocytosis by monocytes independently of the antibody neutralization potential. Surprisingly, we find that both convalescent patient plasma and patient-derived monoclonal antibodies lead to maximum opsonization already at low levels of bound antibodies and is reduced as antibody binding to Spike protein increases. Moreover, we show that this Spike-dependent modulation of opsonization correlate with the outcome in an experimental SARS-CoV-2 infection model. These results suggest that the levels of anti-Spike antibodies could influence monocyte-mediated immune functions and propose that non-neutralizing antibodies could confer protection to SARS-CoV-2 infection by mediating phagocytosis.
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| 43. |
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| 44. |
- Bar, Yael, et al.
(författare)
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Quantitative and semi-quantitative histopathological examination of renal biopsies in healthy individuals, and associations with kidney function
- 2016
-
Ingår i: Apmis. - : Wiley. - 0903-4641. ; 124:5, s. 393-400
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Tidskriftsartikel (refereegranskat)abstract
- This study assesed the prevalence of histopathological changes in renal biopsies from healthy individuals, and the association with age, sex and smoking. Donor biopsies from 109 subjects were obtained from living kidney donors, and blood and urine samples were collected together with medical history. All biopsies were scored according to the Banff 97 classification with some modifications. The parameters included in this study were tubular atrophy, interstitial fibrosis, glomerulosclerosis, arteriosclerosis, arteriolohyalinosis and a sclerosis score. An alternative scoring system for tubular atrophy was examined (using 5% rather than <1% as a cut-off for grade 0). Glomerular filtration rate was measured in most cases as chromium ethylenediaminetetra-acetic acid (Cr-EDTA) clearance. Age was a significant predictor for tubular atrophy, fibrosis and sclerosis. Pack-years of smoking increased the risk of tubular atrophy, fibrosis and arteriolohyalinosis. The alternative scoring of tubular atrophy showed a stronger association with smoking, but a weaker association with age, compared with the original one. Limited histopathological changes are common in healthy kidney donors around 50 years of age with normal kidney function. We propose that a cut-off of 5% yields a better definition of grade 0 tubular atrophy compared with the established cut-off of >0%.
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| 45. |
- Barregård, Lars, 1948, et al.
(författare)
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Cadmium, mercury, and lead in kidney cortex of living kidney donors: Impact of different exposure sources.
- 2010
-
Ingår i: Environmental research. - : Elsevier BV. - 1096-0953 .- 0013-9351. ; 110:1, s. 47-54
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Most current knowledge on kidney concentrations of nephrotoxic metals like cadmium (Cd), mercury (Hg), or lead (Pb) comes from autopsy studies. Assessment of metal concentrations in kidney biopsies from living subjects can be combined with information about exposure sources like smoking, diet, and occupation supplied by the biopsied subjects themselves. OBJECTIVES: To determine kidney concentrations of Cd, Hg, and Pb in living kidney donors, and assess associations with common exposure sources and background factors. METHODS: Metal concentrations were determined in 109 living kidney donors aged 24-70 years (median 51), using inductively coupled plasma-mass spectrometry (Cd and Pb) and cold vapor atomic fluorescence spectrometry (Hg). Smoking habits, occupation, dental amalgam, fish consumption, and iron stores were evaluated. RESULTS: The median kidney concentrations were 12.9microg/g (wet weight) for cadmium, 0.21microg/g for mercury, and 0.08microg/g for lead. Kidney Cd increased by 3.9microg/g for a 10 year increase in age, and by 3.7microg/g for an extra 10 pack-years of smoking. Levels in non-smokers were similar to those found in the 1970s. Low iron stores (low serum ferritin) in women increased kidney Cd by 4.5microg/g. Kidney Hg increased by 6% for every additional amalgam surface, but was not associated with fish consumption. Lead was unaffected by the background factors surveyed. CONCLUSIONS: In Sweden, kidney Cd levels have decreased due to less smoking, while the impact of diet seems unchanged. Dental amalgam is the main determinant of kidney Hg. Kidney Pb levels are very low due to decreased exposure.
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| 46. |
- Bengtsson, Viveca Wallin, et al.
(författare)
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Periodontitis related to cardiovascular events and mortality : a long-time longitudinal study
- 2021
-
Ingår i: Clinical Oral Investigations. - : Springer Science and Business Media Deutschland GmbH. - 1432-6981 .- 1436-3771. ; 25:6, s. 4085-4095
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Tidskriftsartikel (refereegranskat)abstract
- Objective: The present study assessed if individuals ≥ 60 years of age with periodontitis are more likely to develop stroke or ischemic heart diseases, or at a higher risk of death for 17 years. Material and methods: At baseline individuals ≥ 60 received a dental examination including a panoramic radiograph. Periodontitis was defined as having ≥ 30% sites with ≥ 5-mm distance from the cementoenamel junction to the marginal bone level. Medical records were annually reviewed from 2001 to 2018. Findings from the medical records identifying an ICD-10 code of stroke and ischemic heart diseases or death were registered. Results: Associations between periodontitis and incidence of ischemic heart disease were found in this 17-year follow-up study in all individuals 60–93 years (HR: 1.5, CI: 1.1–2.1, p = 0.017), in women (HR: 2.1, CI: 1.3–3.4, p = 0.002), and in individuals 78–96 years (HR: 1.7, CI: 1.0–2.6, p = 0.033). Periodontitis was associated with mortality in all individuals (HR: 1.4, CI: 1.2–1.8, p = 0.002), specifically in men (HR: 1.5, CI: 1.1–1.9, p = 0.006) or in ages 60–72 years (HR: 2.2, CI: 1.5–3.2, p = 0.000). Periodontitis was more prevalent among men (OR: 1.8, CI: 1.3–2.4, p = 0.000). Conclusions: Individuals with periodontitis have an increased risk for future events of ischemic heart diseases and death. Clinical relevance: Improving periodontal health in older individuals may reduce overall mortality and ischemic heart diseases. Both dental and medical professionals should be aware of the associations and ultimately cooperate. © 2021, The Author(s).
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| 47. |
- Bergqvist, Tomas, 1962-
(författare)
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To explore and verify in mathematics
- 2001
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- This dissertation consists of four articles and a summary. The main focus of the studies is students' explorations in upper secondary school mathematics. In the first study the central research question was to find out if the students could learn something difficult by using the graphing calculator. The students were working with questions connected to factorisation of quadratic polynomials, and the factor theorem. The results indicate that the students got a better understanding for the factor theorem, and for the connection between graphical and algebraical representations. The second study focused on a the last part of an investigation, the verification of an idea or a conjecture. Students were given three conjectures and asked to decide if they were true or false, and also to explain why the conjectures were true or false. In this study I found that the students wanted to use rather abstract mathematics in order to verify the conjectures. Since the results from the second study disagreed with other research in similar situations, I wanted to see what Swedish teachers had to say of the students' ways to verify the conjectures. The third study is an interview study where some teachers were asked what expectations they had on students who were supposed to verify the three conjectures from the second study. The teachers were also confronted with examples from my second study, and asked to comment on how the students performed. The results indicate that teachers tend to underestimate students' mathematical reasoning. A central focus to all my three studies is explorations in mathematics. My fourth study, a revised version of a pilot study performed 1998, concerns exactly that: how students in upper secondary school explore a mathematical concept. The results indicate that the students are able to perform explorations in mathematics, and that the graphing calculator has a potential as a pedagogical aid, it can be a support for the students' mathematical reasoning.
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| 48. |
- Bergstrand, Martin, 1977-, et al.
(författare)
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Prediction-Corrected Visual Predictive Checks for Diagnosing Nonlinear Mixed-Effects Models
- 2011
-
Ingår i: AAPS Journal. - : Springer Science and Business Media LLC. - 1550-7416. ; 13:2, s. 143-151
-
Tidskriftsartikel (refereegranskat)abstract
- Informative diagnostic tools are vital to the development of useful mixed-effects models. The Visual Predictive Check (VPC) is a popular tool for evaluating the performance of population PK and PKPD models. Ideally, a VPC will diagnose both the fixed and random effects in a mixed-effects model. In many cases, this can be done by comparing different percentiles of the observed data to percentiles of simulated data, generally grouped together within bins of an independent variable. However, the diagnostic value of a VPC can be hampered by binning across a large variability in dose and/or influential covariates. VPCs can also be misleading if applied to data following adaptive designs such as dose adjustments. The prediction-corrected VPC (pcVPC) offers a solution to these problems while retaining the visual interpretation of the traditional VPC. In a pcVPC, the variability coming from binning across independent variables is removed by normalizing the observed and simulated dependent variable based on the typical population prediction for the median independent variable in the bin. The principal benefit with the pcVPC has been explored by application to both simulated and real examples of PK and PKPD models. The investigated examples demonstrate that pcVPCs have an enhanced ability to diagnose model misspecification especially with respect to random effects models in a range of situations. The pcVPC was in contrast to traditional VPCs shown to be readily applicable to data from studies with a priori and/or a posteriori dose adaptations.
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| 49. |
- Berntsson, Tommy, et al.
(författare)
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Ambulanssjukvården måste bli jämlik
- 2013
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Ingår i: Helsingborgs Dagblad. - Helsingborg : Helsingborgs Dagblad. - 1103-9388. ; 2013-06-17
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Skiftande vårdkvalité hotar patientsäkerheten inom ambulanssjukvården. Nu måste regeringen och Socialstyrelsen skapa nationella riktlinjer, skriver Nätverket för utbildning av ambulanssjuksköterskor .
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| 50. |
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