| 1. |
- Anderberg, Elsie, et al.
(författare)
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Micro processes of learning : Exploring the interplay between conceptions, meanings and expressions
- 2009
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Ingår i: Higher Education. - : Springer Science and Business Media LLC. - 0018-1560 .- 1573-174X. ; 58:5, s. 653-668
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Tidskriftsartikel (refereegranskat)abstract
- The article describes qualitative variation in micro processes of learning, focusing the dynamic interplay between conceptions, expressions and meanings of expressions in students' learning in higher education. The intentional-expressive approach employed is an alternative approach to the function of language use in learning processes. In the empirical investigation, a dialogue model was used that both stimulates and documents students' ways of processing meaning. Results were grouped into three descriptive categories: vague, stabilising and developing ways of processing. Educational implications include, firstly, two distinct types of vague constitution of meaning in learning: one connected to fragmentary relationships between expressions and meanings, and another that triggers and creates close relationships and changes in relationships. Secondly, the categories display different unexplored ways of processing, related to deep and surface approaches in students' learning.
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| 2. |
- Anderberg, Elsie, et al.
(författare)
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The epistemological role of language use in learning : A phenomenographic intentional-expressive approach
- 2008
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Ingår i: Educational Research Review. - 1747-938X .- 1878-0385. ; 3:1, s. 14-29
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Tidskriftsartikel (refereegranskat)abstract
- In research on learning, one of the fundamental questions concerns issues of language and thought. A number of empirical studies have revealed the interplay between understanding of subject matter and meanings of language expressions to be more dynamic and ambiguous than is commonly acknowledged. The aim of this article is to outline an alternative intentional-expressive approach to the interplay between use of language and understanding of subject matter as a contribution to the theoretical development in research on learning. The approach is based on a conception of language that focuses on the function of learners' language use in relation to subject matter in developing and expressing understanding. The learner is seen as an agent, and the focus is on the use of language from the learner's perspective. Four aspects of the relation between learners and subject matter are described and discussed. Conclusions concern the value of this approach as a complement and alternative to the dominant communicative and cognitive approaches to the role of language in learning.
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| 3. |
- Baumann, Pia, et al.
(författare)
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Outcome in a prospective phase II trial of medically inoperable stage I non-small-cell lung cancer patients treated with stereotactic body radiotherapy.
- 2009
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Ingår i: Journal of clinical oncology : official journal of the American Society of Clinical Oncology. - 1527-7755 .- 0732-183X. ; 27:20, s. 3290-6
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The impact of stereotactic body radiotherapy (SBRT) on 3-year progression-free survival of medically inoperable patients with stage I non-small-cell lung cancer (NSCLC) was analyzed in a prospective phase II study. PATIENTS AND METHODS: Fifty-seven patients with T1NOMO (70%) and T2N0M0 (30%) were included between August 2003 and September 2005 at seven different centers in Sweden, Norway, and Denmark and observed up to 36 months. SBRT was delivered with 15 Gy times three at the 67% isodose of the planning target volume. RESULTS: Progression-free survival at 3 years was 52%. Overall- and cancer-specific survival at 1, 2, and 3 years was 86%, 65%, 60%, and 93%, 88%, 88%, respectively. There was no statistically significant difference in survival between patients with T1 or T2 tumors. At a median follow-up of 35 months (range, 4 to 47 months), 27 patients (47%) were deceased, seven as a result of lung cancer and 20 as a result of concurrent disease. Kaplan-Meier estimated local control at 3 years was 92%. Local relapse was observed in four patients (7%). Regional relapse was observed in three patients (5%). Nine patients (16%) developed distant metastases. The estimated risk of all failure (local, regional, or distant metastases) was increased in patients with T2 (41%) compared with those with T1 (18%) tumors (P = .027). CONCLUSION: With a 3-year local tumor control rate higher than 90% with limited toxicity, SBRT emerges as state-of-the-art treatment for medically inoperable stage I NSCLC and may even challenge surgery in operable instances.
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| 4. |
- Baumann, Pia, et al.
(författare)
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Stereotactic body radiotherapy for medically inoperable patients with stage I non-small cell lung cancer - a first report of toxicity related to COPD/CVD in a non-randomized prospective phase II study.
- 2008
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Ingår i: Radiotherapy and oncology : journal of the European Society for Therapeutic Radiology and Oncology. - : Elsevier BV. - 0167-8140 .- 1879-0887. ; 88:3, s. 359-67
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND AIMS: In a retrospective study using stereotactic body radiotherapy (SBRT) in medically inoperable patients with stage I NSCLC we previously reported a local control rate of 88% utilizing a median dose of 15Gyx3. This report records the toxicity encountered in a prospective phase II trial, and its relation to coexisting chronic obstructive pulmonary disease (COPD) and cardio vascular disease (CVD). MATERIAL AND METHODS: Sixty patients were entered in the study between August 2003 and September 2005. Fifty-seven patients (T1 65%, T2 35%) with a median age of 75 years (59-87 years) were evaluable. The baseline mean FEV1% was 64% and median Karnofsky index was 80. A total dose of 45Gy was delivered in three fractions at the 67% isodose of the PTV. Clinical, pulmonary and radiological evaluations were made at 6 weeks, 3, 6, 9, 12, 18, and 36 months post-SBRT. Toxicity was graded according to CTC v2.0 and performance status was graded according to the Karnofsky scale. RESULTS: At a median follow-up of 23 months, 2 patients had relapsed locally. No grade 4 or 5 toxicity was reported. Grade 3 toxicity was seen in 12 patients (21%). There was no significant decline of FEV1% during follow-up. Low grade pneumonitis developed to the same extent in the CVD 3/17 (18%) and COPD 7/40 (18%) groups. The incidence of fibrosis was 9/17 (53%) and pleural effusions was 8/17 (47%) in the CVD group compared with 13/40 (33%) and 5/40 (13%) in the COPD group. CONCLUSION: SBRT for stage I NSCLC patients who are medically inoperable because of COPD and CVD results in a favourable local control rate with a low incidence of grade 3 and no grade 4 or 5 toxicity.
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| 5. |
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| 6. |
- Forsberg, Bertil, professor, 1956-, et al.
(författare)
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Coronanedstängningens betydelse för luftföroreningshalter, beräknade hälsokonsekvenser och registrerade uttag av astmaläkemedel i Stockholmsområdet
- 2022
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Nedstängningen av samhällen på grund av pandemin våren 2020 skedde tämligen globalt, varför åtföljande förändringar av utsläpp både lokalt och på långt avstånd kan ha påverkat luftkvaliteten i Stockholm. Denna rapport redovisar tre delstudier: en analys av hur föroreningshalterna i Stockholmsområdet påverkades av den inledande nedstängningen av samhället, en hälsokonsekvensberäkning av vilka hälsoeffekter en sådan förändring av halterna antas medföra, samt en epidemiologisk tidsseriestudie av sambanden mellan registrerat dagligt antal utköp av astmamediciner och halter av luftföroreningar under den inledande nedstängningen och före/efter denna period.Vi har i detta projekt använt två metoder, spridningsmodellering med emissionsdata respektive regressionsanalys med mätdata, för att beräkna hur främst kväveoxidhalterna påverkades av minskade emissioner lokalt, samt hur bl.a halterna av kvävedioxid och ozon i staden avvek ifrån förväntade värden efter hänsyn till meteorologins inverkan på halterna.Spridningsberäkningarna visade att halterna av kvävedioxid minskade med 0,7 μg/m3 under mars-juli till följd av minskad lokal trafik. Utifrån sammanvägningar av publicerade epidemiologiska samband skulle detta leda till cirka 2 dödsfall färre i 9 kommuner med totalt drygt 1,5 miljoner invånare, medan besök och inläggningar på sjukhus för andningsorganen förväntas minska med drygt 24 fall genom minskade lokala utsläpp.Den väderjusterade minskningen av totala NO2 halterna var 2,8 μg/m3, vilket skulle förväntas leda till ungefär 97 färre besök och inläggningar på sjukhus för andningsorganen under samma 5 månader. Men eftersom minskade utsläpp av kväveoxider även följdes av en oväntat stor väderjusterad ökning av marknära ozon förväntas för vissa hälsoutfall en nettoökning av antalet fall, exempelvis av patienter med problem i andningsorganen.Eftersom utköp av förskrivna läkemedel inte kräver att man besöker sjukvården, inte ens att man besöker ett apotek, studerades dagligt antal utköp av astmaläkemedel i relation till variationer i luftföroreningshalterna. Trots en inledande hamstringsvåg med efterföljande svacka i utköp under maj och lägre uppmätta halter av kväveoxider (NOx) och partiklar <10 mikrometer (PM10) än normalt, fanns sammantaget även under april-juli 2020 en statistiskt säkerställd effekt av PM10 och NOx på dagligt antal utköp. När relativa riskökningen per 10 μg/m3 jämförs mellan denna nedstängningsperiod och övrig studieperiod kan konstateras att ökningen av utköp per haltökning var högre under april-juli 2020. För hela perioden 2018 - 2021 visade en meta-skattning över 21 kommuner i Stockholms län på 2,6 procent ökning i uttag av lång- och korttidsverkande astmaläkemedel per 10 μg/m3 ökning av PM10 (medelvärde för samma dygn och det föregående).
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| 7. |
- Gruzieva, Olena, et al.
(författare)
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Comparison of personal exposure to black carbon levels with fixed-site monitoring data and with dispersion modelling and the influence of activity patterns and environment
- 2024
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Ingår i: Journal of Exposure Science and Environmental Epidemiology. - 1559-0631 .- 1559-064X. ; 34:3, s. 538-545
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Tidskriftsartikel (refereegranskat)abstract
- Background: Short-term studies of health effects from ambient air pollution usually rely on fixed site monitoring data or spatio-temporal models for exposure characterization, but the relation to personal exposure is often not known.Objective: We aimed to explore this relation for black carbon (BC) in central Stockholm.Methods: Families (n = 46) with an infant, one parent working and one parent on parental leave, carried battery-operated BC instruments for 7 days. Routine BC monitoring data were obtained from rural background (RB) and urban background (UB) sites. Outdoor levels of BC at home and work were estimated in 24 h periods by dispersion modelling based on hourly real-time meteorological data, and statistical meteorological data representing annual mean conditions. Global radiation, air pressure, precipitation, temperature, and wind speed data were obtained from the UB station. All families lived in the city centre, within 4 km of the UB station.Results: The average level of 24 h personal BC was 425 (s.d. 181) ng/m3 for parents on leave, and 394 (s.d. 143) ng/m3 for working parents. The corresponding fixed-site monitoring observations were 148 (s.d. 139) at RB and 317 (s.d. 149) ng/m3 at UB. Modelled BC levels at home and at work were 493 (s.d. 228) and 331 (s.d. 173) ng/m3, respectively. UB, RB and air pressure explained only 21% of personal 24 h BC variability for parents on leave and 25% for working parents. Modelled home BC and observed air pressure explained 23% of personal BC, and adding modelled BC at work increased the explanation to 34% for the working parents.Impact: Short-term studies of health effects from ambient air pollution usually rely on fixed site monitoring data or spatio-temporal models for exposure characterization, but the relation to actual personal exposure is often not known. In this study we showed that both routine monitoring and modelled data explained less than 35% of variability in personal black carbon exposure. Hence, short-term health effects studies based on fixed site monitoring or spatio-temporal modelling are likely to be underpowered and subject to bias.
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| 8. |
- Gustafsson, Mats, 1966-, et al.
(författare)
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Driftåtgärder mot PM10 i Stockholm : utvärdering av vintersäsongen 2012–2013
- 2014
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- En ny vakuumsug för att sänka halterna av inandningsbara partiklar (PM10) har testats på några gator i Stockholm. Resultatet av VTI:s mätningar visar att det mest effektiva sättet att sänka PM10-halter är dammbindning med kalciummagnesiumacetat (CMA). Städning med den nya vakuumsugen gav ingen signifikant effekt dagen efter. Sverige uppfyller inte EU:s krav på luftkvaliteten i vår omgivningsluft på grund av de höga halterna av inandningsbara partiklar i våra tätorter. Orsakerna är främst slitage av vägbanor och sandning under vintern. Stockholm är den stad i landet som har störst problem att uppfylla miljökvalitetsnormen för PM10 på grund av många gator med höga trafikflöden och trånga gatuutrymmen. Sedan 2011 pågår ett intensifierat arbete för att sänka partikelhalterna. I detta arbete används några gator som försöksområden för olika åtgärder, vilka jämförs med halterna på gator där inga särskilda insatser görs. Säsongen 2012-2013 har forskarna utvidgat med ytterligare två mätplatser. Detta för att kunna urskilja effekterna av en ny städmaskin med kraftigt vakuum, som inte använder vatten och därför kan användas även då det är minusgrader. Städning med denna maskin har provats som enda extra åtgärd och i kombination med dammbindning med CMA. Resultaten visar att CMA fortsatt är det mest effektiva sättet att sänka akut höga PM10-halter och att effekten dröjer kvar även dagen efter utläggningen. Städning med den nya vakuumsugen gav ingen signifikant effekt på PM10-halterna dagen efter, trots att maskinen kunde visas ta upp partiklar mindre än 10 µm från vägbanan. Data visar att dammängderna når en topp under slutet på vintern/tidig vår, vilket visar på betydelsen av dubbdäcksanvändning och vinterdrift för dammängderna. Dammbindningens effekt kan även visas genom att mängden damm på vägytan på de behandlade gatorna är större och har en finare storleksfördelning än på obehandlade gator. Genom mätningar med laser kan forskarna dessutom konstatera att vägytans textur är en viktig parameter för hur stort dammförrådet på vägytan är och kan ha betydelse för uppvirvlingen av damm från gator och vägar.
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| 9. |
- Gustafsson, Mats, 1966-, et al.
(författare)
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Driftåtgärder mot PM10 i Stockholm : utvärdering av vintersäsongen 2013–2014
- 2015
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Sedan 2011 pågår ett intensifierat arbete för att sänka halterna av PM10 i Stockholm, där problemen är omfattande. Denna rapport presenterar resultat och utvärdering av insatserna gjorda under vintersäsongen 2013–2014. De lägsta PM10-halterna sedan mätningarna startade i Stockholm, uppmättes under säsongen och miljökvalitetsnormen klaras med bred marginal, vilket åtminstone delvis kan bedömas vara en effekt av de intensifierade åtgärderna. Vintern var dock ovanligt mild och snöfattig och har sannolikt bidragit till att de vanligtvis stora dammängder som ansamlas på vägytan i snö och fukt under vintern kunnat lämna systemet genom suspension, städning och avrinning utan att resultera i höga partikelhalter. Under de torra perioderna har dessutom frekvent dammbindning dämpat halterna. Den vanligtvis kraftiga PM10-toppen på våren har därför i stort sett uteblivit. Den kvartersvisa behandlingen visade sig ge ytterligare effekt på PM10-halterna, medan CMA (kalciummagnesiumacetat) + KF (kaliumformiat) inte kunde visas ha någon extra effekt. Mätningarna av vägdammsförrådet uppvisar samma säsongsvariationer som tidigare år, med stora mängder under vintern och mindre mängder under höst och sen vår. Alla gator, utom Hornsgatan, uppvisar en successiv sänkning av vägdammsmängderna under de tre säsonger som mätningar utförts. Andelen partiklar mindre än 10 μm i vägdammet stiger från höst till vinter och avtar igen under våren. Den organiska andelen varierar i genomsnitt mellan 10 och 20 viktprocent av DL180 (dust load mindre än 180 μm).och uppvisar också en säsongsvariation, där andelen är högre på hösten och som lägst tidig vår. I en specifik utvärdering av städmaskinens effekt på vägdammsförrådet kunde en minskning observeras.
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| 10. |
- Gustafsson, Mats, 1966-, et al.
(författare)
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Driftåtgärder mot PM10 i Stockholm : utvärdering av vintersäsongen 2014–2015
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Sedan 2011 pågår ett intensifierat arbete för att sänka halterna av PM10 i Stockholm. Denna rapport presenterar resultat och utvärdering av insatserna gjorda under vintersäsongen 2014–2015. Säsongen uppvisar de lägsta PM10-halterna samt lägst antal dygn över miljökvalitetsnormen för PM10 sedan mätningarna startades i Stockholm år 2000. Beräkningar med NORTRIP-modellen visar att såväl ökad dammbindning, minskad dubbdäcksanvändning, lägre bakgrundshalt som skillnader i meteorologi alla är faktorer som bidragit till att halterna har sjunkit från 2013 till 2015. Behandling med CMA+KF (kaliumformiat) kunde inte visas ge någon extra effekt på PM10-halterna, medan den kvartersvisa dammbindningen gav en ytterligare, men ej statistiskt säkerställd, positiv effekt.Dammförrådet på vägytan har på alla studerade gator utom Hornsgatan en sjunkande trend de senaste tre åren och uppvisar, liksom tidigare säsonger, en säsongsbunden variation med stora mängder på vinter och tidig vår och låga i oktober och maj. Detaljerade mätningar uppvisar en kraftig variation i dammförrådet tvärs gatorna, med stora ansamlingar utanför körfältet. Vägytans textur bedöms spela en viktig roll för dammets ansamling då den påverkar såväl uppvirvlingen från trafiken, som möjligheten att städa bort dammet. Rapporten ger, utifrån säsongens resultat i kombination med data om åtgärder och meteorologi, några förslag till hur åtgärderna kan förbättras och ger även exempel på hur extra behov eller onödiga insatser kan sökas fram ur befintlig data.
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| 11. |
- Gustafsson, Mats, 1966-, et al.
(författare)
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Driftåtgärder mot PM10 i Stockholm : utvärdering av vintersäsongen 2015–2016
- 2017
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Sedan 2011 pågår ett särskilt arbete i Stockholm för att minska PM10-halterna i staden. Insatserna omfattar främst dammbindning med CMA (kalciummagnesiumacetat) och vakuumsugning med en kraftig, torr vakuumsugningsmaskin. Denna rapport sammanfattar effekter på partikelhalter och vägdammsförråd, av de åtgärder som Stockholms stad utfört under säsongen 2015–2016 och diskuterar hur åtgärderna kan ytterligare förbättras. Miljökvalitetsnormen klarades säsongen 2015–2016 för tredje året i rad, men antalet dagar med PM10-halter över miljökvalitetsnormens gränsvärde var högre än föregående säsong, som hade rekordlågt antal överskridanden. Utvärderingen av dagtids dammbindning försvårades av att CMA även lades ut på referensgatan, vilket medförde alltför stora osäkerheter för att kunna göra någon kvantitativ analys av dess effekt denna säsong. Kvartersvis dammbindning och vakuumsugning kunde inte utvärderas på grund av att en byggarbetsplats kontaminerade mätningarna. Dammförrådet på gatorna varierar från några enstaka g/m2 till cirka 250 g/m2 beroende på gata och årstid och är som högst under vintern (dec–jan). En trend mot lägre dammängder bryts denna säsong på flera gator, vilket möjligen kan bero på jämförelsevis fuktigare gator på våren denna säsong. Analyserna tyder på att dammbindning på våren är viktigt för att hålla PM10-halterna nere, medan dammbindning på hösten och vintern oftare görs ”i onödan” (då halterna sannolikt inte skulle ha överskridit gränsvärdet även utan dammbindning).
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| 12. |
- Gustafsson, Mats, 1966-, et al.
(författare)
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Driftåtgärder mot PM10 i Stockholm : utvärdering av vintersäsongen 2016/2017
- 2018
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Stockholms stad bedriver sedan 2011 ett arbete med att, genom förbättrade och specifika gatudriftsåtgärder minska uppvirvlingen av vägdamm för att minska partikelhalter i luften. Sedan starten har effekterna på såväl dammförråd som luftkvalitet följts upp av VTI och SLB-analys vid Miljöförvaltningen i Stockholm.Specifika åtgärder har omfattat främst dammbindning med kalciummagnesiumacetat (CMA) och städning med vakuumsug (Disa-Clean). Luftkvalitetsmätningarna visar att miljökvalitetsnormen för PM10 klaras för fjärde året i Stockholm vilket delvis bedöms beror på driftåtgärderna. Den extra dagtida dammbindningen kunde visas sänka dygnsmedelvärdet av PM10 med 6 %, medan den kvartersvisa behandlingen inte kunde visas ha någon tydlig effekt. Vägdammsmängderna mätt som DL180 (vägdamm mindre än 180 μm) tenderar att i genomsnitt ha ökat något jämfört med föregående säsong, särskilt i ytorna mellan hjulspåren. Omläggningen av Folkungagatan har resulterat i kraftigt ökade vägdammsmängder, men också lägre PM10-halter än föregående säsonger. Utvärderingen av möjligheterna att optimera dammbindningen visar att flera dagar med överskridanden på hösten missas, medan flera dagar i januari behandlas med CMA utan att behov egentligen föreligger. Högre precision med prognosbaserade åtgärder behövs för optimering av insatserna.
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| 13. |
- Gustafsson, Mats, 1966-, et al.
(författare)
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Driftåtgärder mot PM10 i Stockholm : utvärdering av vintersäsongen 2017–2018
- 2019
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Stockholms stad bedriver sedan 2011 ett arbete med att, genom förbättrade och specifika gatudriftsåtgärder, minska uppvirvlingen av vägdamm för att minska partikelhalter i luften. Sedan starten har effekterna på såväl dammförråd som luftkvalitet följts upp av VTI och SLB-analys vid Miljöförvaltningen i Stockholm. Specifika åtgärder har omfattat främst dammbindning med kalciummagnesiumacetat (CMA) och städning med vakuumsug (Disa-Clean). Innevarande säsong har vakuumsugen dock inte använts. Luftkvalitetsmätningarna visar att miljökvalitetsnormen för PM10 klaras för femte året i Stockholm, men halterna är högre än föregående år. Vägdammsmängderna mätt som DL180 (vägdamm mindre än 180 μm) har generellt ökat vilket varit utvecklingen sedan säsongen 2014–2015. Folkungagatan, som fick en ny beläggning 2016, har fortsatt höga vägdammsmängder, men också lägre PM10-halter än före beläggningsbytet. Utvärderingen av möjligheterna att optimera dammbindningen visar att CMA ofta läggs ut trots att PM10-halterna inte skulle överskridits. Maj var särskilt torr och flera överskridanden kunde då ha förhindrats med CMA, men åtgärden avslutas sista april på grund av risk för halka. Högre precision med till exempel prognosbaserade åtgärder skulle sannolikt vara gynnsamt för optimering av insatserna.
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| 14. |
- Gustafsson, Mats, 1966-, et al.
(författare)
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Optidrift : optimerad vinter- och barmarksdrift för bättre luftkvalitet
- 2019
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Drift av gator och vägar påverkar, förutom framkomlighet och säkerhet, även miljöaspekter som luftkvalitet. Åtgärder som sandning och saltning påverkar halten av inandningsbara partiklar (PM10) i luften. Driftåtgärder som görs för att minska uppvirvlingen av partiklar på våren kan å andra sidan ha effekt på vinterdriften, genom att de saltlösningar som används också fungerar som halkbekämpningsmedel. Projektet har undersökt möjligheterna att optimera gatudriften ur dessa aspekter, med ett fokus på luftkvalitet. I olika aktiviteter inhämtades synpunkter och erfarenheter kring problembild och lösningar från bransch, väghållare och praktiker. En provtagare för vägdamm, WDS II, vidareutvecklades. Utvärderingar av olika spol- och städvarianters effekt på dammförrådet visade att en positiv effekt av metoderna kräver att det finns förhållandevis mycket damm på vägytan. Optimeringstester visade att god prognosstyrning av insatserna är viktigt för ett bra resultat. En kriteriebaserad analys visade att ingen optimering av dammbindningen skett under projektperioden. Sammantaget har projektets ursprungliga mål att kunna föreslå en optimerad gatudrift i en stadsdel i Stockholm inte nåtts, främst beroende av gällande driftkontrakt och av miljökvalitetsmålets (PM10) och framkomlighetens höga prioritet i staden. Däremot har Optidrift identifierat framgångsfaktorer och problem med gatudriften, resulterat i ökad kunskap om gatudriftens effekter på dammförråd och luftkvalitet samt tagit fram användbara utvärderingsmetoder och scenarioanalyser användbara i fortsatt arbete med att förbättra och optimera vinter- och barmarksdrift.
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| 15. |
- Gustafsson, Mats, 1966-, et al.
(författare)
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Particles in road and railroad tunnel air : sources, properties and abatement measures
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- High levels of air pollution are a common problem in both road and railroad tunnels. Sources and emission processes however differ significantly, as reflected by aerosols physical and chemical properties. As particle concentrations and properties affect exposure of and health effects for people on platforms and in vehicles, effective ways to reduce emissions and exposure are important. This study aims to improve the knowledge of the differences between PM10 in the rail and road tunnel environments, their sources and the possibilities to address problems with high particulate levels. Measurement campaigns were carried out at Arlanda Central, a railroad tunnel station below Arlanda airport and in Söderleden road tunnel, a road tunnel in central Stockholm.The results show large differences in concentration levels, size distributions and in composition of the particles. The railroad tunnel aerosol consisted of coarse particles with high iron content, while the properties of the coarse particles in the road tunnel were strongly influenced by whether the road surface was wet or dry. In wet conditions, concentrations were relatively low and iron and sulfur dominating elements, while silicon, potassium, calcium and iron from suspension and road wear dominated during dry conditions. The content of elemental carbon, most likely from the pantograph, were unexpectedly high in the railroad tunnel. An older type of train with a large proportion of mechanical brakes were suggested to be responsible to the main particle emissions in the railway tunnel. The report concludes with a discussion and proposals for action against particle sources in the various underground environments.
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| 16. |
- Hallqvist, Andreas, 1973, et al.
(författare)
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Concurrent cetuximab and radiotherapy after docetaxel-cisplatin induction chemotherapy in stage III NSCLC : Satellite-A phase II study from the Swedish Lung Cancer Study Group
- 2011
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Ingår i: Lung Cancer. - : Elsevier BV. - 0169-5002 .- 1872-8332. ; 71:2, s. 166-172
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Tidskriftsartikel (refereegranskat)abstract
- Background: Several attempts to increase the locoregional control in locally advanced lung cancer including concurrent chemotherapy, accelerated fractionation and dose escalation have been made during the last years. As the EGFR directed antibody cetuximab has shown activity concurrent with radiotherapy in squamous cell carcinoma of the head and neck, as well as in stage IV NSCLC combined with chemotherapy, we wanted to investigate radiotherapy with concurrent cetuximab in locally advanced NSCLC, a tumour type often over expressing the EGF-receptor. Methods: Between February 2006 and August 2007 75 patients in stage Ill NSCLC with good performance status (PS 0 or 1) and adequate lung function (FEV1 > 1.0) were enrolled in this phase II study at eight institutions. Treatment consisted of 2 cycles of induction chemotherapy, docetaxel 75 mg/m(2) and cisplatin 75 mg/m(2) with 3 weeks interval. An initial dose of cetuximab 400 mg/m(2) was given before start of 3D-CRT to 68 Gy with 2 Gy per fraction in 7 weeks concurrent with weekly cetuximab 250 mg/m(2). Toxicity was scored weekly during radiotherapy (CTC 3.0), and after treatment the patients were followed every third month with CT-scans, toxicity scoring and QLQ. Results: Seventy-one patients were eligible for analysis as four were incorrectly enrolled. Histology: adenocarcinoma 49%, squamous cell carcinoma 39% and other NSCLC 12%. The majority had PS 0 (62.5%), median age 62.2 (42-81), 50% were women and 37% had a pre-treatment weight loss > 5%. Toxicity: esophagitis grade 1-2: 72%; grade 3:1.4%. Hypersensitivity reactions grade 3-4: 5.6%. Febrile neutropenia grade 3-4: 15.4%. Skin reactions grade 1-2: 74%; grade 3: 4.2%. Diarrhoea grade 1-2: 38%; grade 3: 11.3%. Pneumonitis grade 1-2: 26.8%; grade 3: 4.2%; grade 5:1.4%. The median follow-up was 39 months for patients alive and the median survival was 17 months with a 1-, 2- and 3-year OS of 66%, 37% and 29% respectively. Until now local or regional failure has occurred in 20 patients and 22 patients have developed distant metastases. Weight loss, PS and stage were predictive for survival in univariate as well as in multivariate analysis. Conclusion: Induction chemotherapy followed by concurrent cetuximab and RT to 68 Gy is clearly feasible with promising survival. Toxicity, e.g. pneumonitis and esophagitis is low compared to most schedules with concurrent chemotherapy. This treatment strategy should be evaluated in a randomised manner vs. concurrent chemoradiotherapy to find out if it is a valid treatment option.
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| 17. |
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| 18. |
- Johansson, Christine, 1956-, et al.
(författare)
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Syntactic aspects of the writing of Swedish L2 learners of English
- 2011. - 1
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Ingår i: Corpus-based studies in language use, language learning, and language documentation. - Amsterdam : Rodopi. - 9789042034013 ; , s. 139-155
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Bokkapitel (refereegranskat)abstract
- The present study focuses on syntactic development in Swedish high school students’ writing. The data is drawn from the Uppsala Learner English Corpus (ULEC), consisting of essays written by Swedish junior and senior high school students. In measuring syntactic development in the students’ writing, we make use of various indices, including number of T-units, proportion of syntactically error-free T-units, and the subordinate clause index. In the statistical analysis of the data, syntactic development is analyzed across age, school level, and gender. Senior high school students write longer and more complex T-units, in that they have a more frequent and varied use of subordinate clauses. Contrary to previous research on gender differences in second language acquisition, our results show that, controlling for age and school level, there are no statistically significant differences between boys and girls when they write essays in English.
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| 19. |
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| 20. |
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| 21. |
- Johansson, Thorsten, 1956-, et al.
(författare)
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Agent perspective, objectivity and language
- 2005
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Ingår i: Paper presented at NFPF/NERA 33rd Congress in Oslo, Norway, 10-12 March 2005. - Lund : Pedagogiska institutionen, Lunds universitet.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 22. |
- Kriit, Hedi Katre, et al.
(författare)
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A health economic assessment of air pollution effects under climate neutral vehicle fleet scenarios in Stockholm, Sweden
- 2021
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Ingår i: Journal of Transport and Health. - : Elsevier BV. - 2214-1405 .- 2214-1413. ; 22
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Electric vehicles (EVs) are heavily promoted as beneficial for climate and health. In most studies, it is assumed that EVs contribution to urban air pollution is zero due to no tailpipe emissions, ignoring the contribution of non-exhaust particles (brake, tire and road wear), which are unregulated in EU. This study of Stockholm, Sweden, aims to 1) assess how a future vehicle fleet impacts concentrations of particles of size less than 2.5 μm (PM2.5) and evaluate the expected health outcomes economically and 2) compare this with CO2 savings. Methods: Source specific dispersion models of exhaust and non-exhaust PM2.5 was used to estimate the population weighted concentrations. Thereafter exposure differences within a business as usual (BAU2035) and a fossil free fuel (FFF2035) scenario were used to assess expected health and economic impacts. The assessment considered both exhaust and non-exhaust emissions, considering the vehicle weight and the proportion of vehicles using studded winter tires. Health economic costs were retrieved from the literature and societal willingness to pay was used to value quality-adjusted life-years lost due to morbidity and mortality. Results: The mean population weighted exhaust PM2.5 concentration decreased 0.012 μg/m3 (39%) in FFF2035 as compared to BAU2035. Assuming 50% higher road and tire wear PM2.5 emission because of higher weight among EVs and 30% less brake wear emissions, the estimated decrease in wear particle exposures were 0.152 (22%) and 0.014 μg/m3 (1.9%) for 0 and 30% use on studded winter tires, respectively. The resulting health economic costs were estimated to €217M and €32M, respectively. An increase by 0.079 μg/m3 (11%) was however estimated for 50% use of studded winter tires, corresponding to an €89M increase in health costs. Conclusion: Considering both exhaust and wear generated particles, it is not straight forward that an increase of EVs will decrease the negative health impacts.
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| 23. |
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| 24. |
- Mårtensson, Monica, 1956-
(författare)
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Submicrometre aerosol emissions from sea spray and road traffic
- 2007
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The uncertainty of the climate and health effects of aerosols is still large, one important reason being lack of knowledge of the primary emissions. This thesis combines laboratory and field experiments, and process modelling in an effort to better quantify the submicrometre aerosol emissions and to understand some of the processes in the atmosphere.A parameterisation was derived for the source flux of sea salt particles (particles m-2 s-1) in the size range 0.02-2.8 µm dry diameter (Dp), it is the first parameterisation to almost cover two full decades of the submicrometre sea salt aerosol production, and to include the effect of water temperature. This sea salt parameterisation was validated for temperate water in the 0.1-1.1 μm Dp range using in situ size resolved emissions of marine aerosol particles, which were measured with the eddy covariance (EC) method. For periods sampled air was heated to 300ºC in order to evaporate semi-volatile organics and isolate the sea salt fraction. Comparisons with the total aerosol emissions suggest that in these emissions organic carbon and sea salt are internally mixed in the same particles. Finally an aerosol dynamics model was modified for marine conditions. In the model parameterised emissions of sea salt was included together with aerosol dynamics, chemistry and clouds representative for the marine boundary layer. The sea salt emissions are together with secondary sulphate, and cloud processing able to reproduce a typical marine aerosol size distribution and cloud condensation nuclei population.Measurements with the EC method of the road traffic related aerosol source number flux for Dp>0.011 µm show that the major part of the aerosol fluxes is due to road traffic emissions. Both an emission factor for the whole fleet mix in Stockholm (1.4x1014 vehicle-1 km-1) and separate emission factors for light- and heavy-duty vehicles (HDV) were deduced. The result shows that during weekdays 70-80% of the emissions come from HDV.
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| 25. |
- Nilsson Sommar, Johan, et al.
(författare)
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Long-term exposure to particulate air pollution and black carbon in relation to natural and cause-specific mortality: a multicohort study in Sweden
- 2021
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Ingår i: Bmj Open. - : BMJ. - 2044-6055. ; 11:9
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Tidskriftsartikel (refereegranskat)abstract
- Objectives To estimate concentration-response relationships for particulate matter (PM) and black carbon (BC) in relation to mortality in cohorts from three Swedish cities with comparatively low pollutant levels. Setting Cohorts from Gothenburg, Stockholm and Umea, Sweden. Design High-resolution dispersion models were used to estimate annual mean concentrations of PM with aerodynamic diameter <= 10 mu m (PM10) and <= 2.5 mu m (PM2.5), and BC, at individual addresses during each year of follow-up, 1990-2011. Moving averages were calculated for the time windows 1-5 years (lag1-5) and 6-10 years (lag6-10) preceding the outcome. Cause-specific mortality data were obtained from the national cause of death registry. Cohort-specific HRs were estimated using Cox regression models and then meta-analysed including a random effect of cohort. Participants During the study period, 7 340 cases of natural mortality, 2 755 cases of cardiovascular disease (CVD) mortality and 817 cases of respiratory and lung cancer mortality were observed among in total 68 679 individuals and 689 813 person-years of follow-up. Results Both PM10 (range: 6.3-41.9 mu g/m(3)) and BC (range: 0.2-6.8 mu g/m(3)) were associated with natural mortality showing 17% (95% CI 6% to 31%) and 9% (95% CI 0% to 18%) increased risks per 10 mu g/m(3) and 1 mu g/m(3) of lag1-5 exposure, respectively. For PM2.5 (range: 4.0-22.4 mu g/m(3)), the estimated increase was 13% per 5 mu g/m(3), but less precise (95% CI -9% to 40%). Estimates for CVD mortality appeared higher for both PM10 and PM2.5. No association was observed with respiratory mortality. Conclusion The results support an effect of long-term air pollution on natural mortality and mortality in CVD with high relative risks also at low exposure levels. These findings are relevant for future decisions concerning air quality policies.
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| 26. |
- Nilsson Sommar, Johan, et al.
(författare)
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Overall health impacts of a potential increase in cycle commuting in Stockholm, Sweden
- 2022
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Ingår i: Scandinavian Journal of Public Health. - : Sage Publications. - 1403-4948 .- 1651-1905. ; 50, s. 552-564
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: To estimate the overall health impact of transferring commuting trips from car to bicycle..Design and setting: In this study registry information on location of home and work for residents in the County of Stockholm was used to obtain the shortest travel route on a network of bicycle paths and roads. Current modes of travel to work were based on travel survey data. The relation between duration of cycling and distance cycled was established as a basis for selecting the number of individuals that normally would drive a car to their work place, but have a distance to work that they could bicycle within 30 minutes. The change in traffic flows was estimated by a transport model (LuTrans) and effects on road traffic injuries and fatalities were estimated by using national hospital injury data. Effects on air pollution concentrations were modelled using dispersion models.Results: Within the scenario, 111 000 commuters would shift from car to bicycle. This corresponds to 32% of the existing car commuters. On average the increased physical activity reduced the one-year mortality risk by 12% among the additional bicyclists corresponding to 16 fewer premature deaths per year. Including the number of years lost due to morbidity, the total number of disability adjusted life years (DALYs) gained was 696. The amount of DALYs per year gained in the general population due to reduced air pollution concentrations at home addresses was 471. The number of DALYs lost by traffic injuries was 176. Including also air pollution effects among bicyclists, the scenario was calculated to each year give a net benefit of 939 DALYs.Conclusion: The health impact assessment of transferring commuting by car to bicycle estimated large health benefits even then considering injuries and air pollution exposure among bicyclists.
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| 27. |
- Olstrup, Henrik, et al.
(författare)
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Seasonal variations in the daily mortality associated with exposure to particles, nitrogen dioxide, and ozone in stockholm, sweden, from 2000 to 2016
- 2021
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Ingår i: Atmosphere. - : MDPI. - 2073-4433. ; 12:11
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Tidskriftsartikel (refereegranskat)abstract
- Urban air pollutant emissions and concentrations vary throughout the year due to various factors, e.g., meteorological conditions and human activities. In this study, seasonal variations in daily mortality associated with increases in the concentrations of PM10 (particulate matter), PM2.5–10 (coarse particles), BC (black carbon), NO2 (nitrogen dioxide), and O3 (ozone) were calculated for Stockholm during the period from 2000 to 2016. The excess risks in daily mortality are presented in single and multi-pollutant models during the whole year and divided into four different seasons, i.e., winter (December–February), spring (March–May), summer (June–August), and autumn (September–November). The excess risks in the single-pollutant models associated with an interquartile range (IQR) increase for a lag 02 during the whole year were 0.8% (95% CI: 0.1–1.4) for PM10, 1.1% (95% CI: 0.4–1.8) for PM2.5–10, 0.5% (95% CI: −0.5–1.5) for BC, −1.5% (95% CI: −0.5–−2.5) for NO2, and 1.9% (95% CI: 1.0–2.9) for O3. When divided into different seasons, the excess risks for PM10 and PM2.5–10 showed a clear pattern, with the strongest associations during spring and autumn, but with weaker associations during summer and winter, indicating increased risks associated with road dust particles during these seasons. For BC, which represents combustion-generated particles, the pattern was not very clear, but the strongest positive excess risks were found during autumn. The excess risks for NO2 were negative during all seasons, and in several cases even statistically significantly negative, indicating that NO2 in itself was not harmful at the concentrations prevailing during the measurement period (mean values < 20 µg m−3). For O3, the excess risks were statistically significantly positive during “all year” in both the single and the multi-pollutant models. The excess risks for O3 in the single-pollutant models were also statistically significantly positive during all seasons.
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| 28. |
- Sandgren, Andreas, 1978, et al.
(författare)
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Performance Measurement Systems for SME in Collaborative Settings
- 2006
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Ingår i: Proceedings of the 16th Annual POMS Conference, Boston, MA, 28 April-1 May.
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Konferensbidrag (refereegranskat)abstract
- Small and medium size enterprises (SMEs) do in many cases not have the financial strength, range of knowledge, or technical resources that are necessary in order to compete successfully with larger companies. One way for the individual company to solve this problem is through collaboration with other companies, large as well as small. There are different kinds and different levels of collaboration that may offer different possibilities and prerequisites to create competitive manufacturing. To evaluate the collaboration between companies, a performance measurement system which takes quantitative as well as qualitative factors into consideration is required. This paper presents a review over possible performance measurement systems and parameters that should be considered in the decision of performance measures.
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| 29. |
- Segersson, David, et al.
(författare)
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Near-source risk functions for particulate matter are critical when assessing the health benefits of local abatement strategies
- 2021
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Ingår i: International Journal of Environmental Research and Public Health. - : MDPI. - 1661-7827 .- 1660-4601. ; 18:13
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Tidskriftsartikel (refereegranskat)abstract
- When mortality or other health outcomes attributable to fine particulate matter (PM2.5) are estimated, the same exposure–response function (ERF) is usually assumed regardless of the source and composition of the particles, and independently of the spatial resolution applied in the exposure model. While several recent publications indicate that ERFs based on exposure models resolving within-city gradients are steeper per concentration unit (μgm−3), the ERF for PM2.5 recommended by the World Health Organization does not reflect this observation and is heavily influenced by studies based on between-city exposure estimates. We evaluated the potential health benefits of three air pollution abatement strategies: electrification of light vehicles, reduced use of studded tires, and introduction of congestion charges in Stockholm and Gothenburg, using different ERFs. We demonstrated that using a single ERF for PM2.5 likely results in an underestimation of the effect of local measures and may be misleading when evaluating abatement strategies. We also suggest applying ERFs that distinguish between near-source and regional contributions of exposure to PM2.5. If separate ERFs are applied for near-source and regional PM2.5, congestion charges as well as a reduction of studded tire use are estimated to be associated with a significant reduction in the mortality burden in both Gothenburg and Stockholm. In some scenarios the number of premature deaths is more than 10 times higher using separate ERFs in comparison to using a single ERF irrespective of sources as recommended by the WHO. For electrification, the net change in attributable deaths is small or within the uncertainty range depending on the choice of ERF.
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| 30. |
- Sundström, Johan, Professor, 1971-, et al.
(författare)
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Rationale for a Swedish cohort consortium
- 2019
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Ingår i: Upsala Journal of Medical Sciences. - : Taylor & Francis Group. - 0300-9734 .- 2000-1967. ; 124:1, s. 21-28
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Tidskriftsartikel (refereegranskat)abstract
- We herein outline the rationale for a Swedish cohort consortium, aiming to facilitate greater use of Swedish cohorts for world-class research. Coordination of all Swedish prospective population-based cohorts in a common infrastructure would enable more precise research findings and facilitate research on rare exposures and outcomes, leading to better utilization of study participants' data, better return of funders' investments, and higher benefit to patients and populations. We motivate the proposed infrastructure partly by lessons learned from a pilot study encompassing data from 21 cohorts. We envisage a standing Swedish cohort consortium that would drive development of epidemiological research methods and strengthen the Swedish as well as international epidemiological competence, community, and competitiveness.
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| 31. |
- Svensson, Lennart, et al.
(författare)
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The use of language in understanding subject matter
- 2009
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Ingår i: Instructional science. - : Springer Science and Business Media LLC. - 0020-4277 .- 1573-1952. ; 37:3, s. 205-225
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Tidskriftsartikel (refereegranskat)abstract
- Empirical results show that frequently the meaning of expressions used by students in expressing their understanding of subject matter does not correspond to the meaning of those expressions in the subject matter theory that the students are expected to learn. There is also often a lack of identity of meaning between the same students' use of the same expression from one use of the expression to another, in very similar contexts. The context gives a specific meaning to any expression. This variation in context and meaning is very central to the phenomena of teaching and learning. In educational research there is a need to differentiate between specific meanings expressed in conceptualizing subject matter, on the one hand, and concepts and meanings seen as parts of cognitive systems and social languages, on the other. The contextual character of the use of language is crucial to the understanding of teaching and learning and needs to be more carefully considered. The article is a discussion of the problem of varying meanings of language expressions in relation to major traditions of research, focusing on meanings and concepts within the field of learning and teaching.
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| 32. |
- Vallabani, N. V. Srikanth, et al.
(författare)
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Toxicity and health effects of ultrafine particles : Towards an understanding of the relative impacts of different transport modes
- 2023
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Ingår i: Environmental Research. - : Elsevier BV. - 0013-9351 .- 1096-0953. ; 231
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Forskningsöversikt (refereegranskat)abstract
- Exposure to particulate matter (PM) has been associated with a wide range of adverse health effects, but it is still unclear how particles from various transport modes differ in terms of toxicity and associations with different human health outcomes. This literature review aims to summarize toxicological and epidemiological studies of the effect of ultrafine particles (UFPs), also called nanoparticles (NPs, <100 nm), from different transport modes with a focus on vehicle exhaust (particularly comparing diesel and biodiesel) and non-exhaust as well as particles from shipping (harbor), aviation (airport) and rail (mainly subway/underground). The review includes both particles collected in laboratory tests and the field (intense traffic environments or collected close to harbor, airport, and in subway). In addition, epidemiological studies on UFPs are reviewed with special attention to studies aimed at distinguishing the effects of different transport modes. Results from toxicological studies indicate that both fossil and biodiesel NPs show toxic effects. Several in vivo studies show that inhalation of NPs collected in traffic environments not only impacts the lung, but also triggers cardiovascular effects as well as negative impacts on the brain, although few studies compared NPs from different sources. Few studies were found on aviation (airport) NPs, but the available results suggest similar toxic effects as traffic-related particles. There is still little data related to the toxic effects linked to several sources (shipping, road and tire wear, subway NPs), but in vitro results highlighted the role of metals in the toxicity of subway and brake wear particles. Finally, the epidemiological studies emphasized the current limited knowledge of the health impacts of source-specific UFPs related to different transport modes. This review discusses the necessity of future research for a better understanding of the relative potencies of NPs from different transport modes and their use in health risk assessment.
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| 33. |
- Zhang, Zhiguo, et al.
(författare)
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Improving 3-day deterministic air pollution forecasts using machine learning algorithms
- 2024
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Ingår i: Atmospheric Chemistry And Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 24:2, s. 807-851
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Tidskriftsartikel (refereegranskat)abstract
- As air pollution is regarded as the single largest environmental health risk in Europe it is important that communication to the public is up to date and accurate and provides means to avoid exposure to high air pollution levels. Long- and short-term exposure to outdoor air pollution is associated with increased risks of mortality and morbidity. Up-to-date information on present and coming days' air quality helps people avoid exposure during episodes with high levels of air pollution. Air quality forecasts can be based on deterministic dispersion modelling, but to be accurate this requires detailed information on future emissions, meteorological conditions and process-oriented dispersion modelling. In this paper, we apply different machine learning (ML) algorithms - random forest (RF), extreme gradient boosting (XGB), and long short-term memory (LSTM) - to improve 1, 2, and 3d deterministic forecasts of PM10, NOx, and O3 at different sites in Greater Stockholm, Sweden. It is shown that the deterministic forecasts can be significantly improved using the ML models but that the degree of improvement of the deterministic forecasts depends more on pollutant and site than on what ML algorithm is applied. Also, four feature importance methods, namely the mean decrease in impurity (MDI) method, permutation method, gradient-based method, and Shapley additive explanations (SHAP) method, are utilized to identify significant features that are common and robust across all models and methods for a pollutant. Deterministic forecasts of PM10 are improved by the ML models through the input of lagged measurements and Julian day partly reflecting seasonal variations not properly parameterized in the deterministic forecasts. A systematic discrepancy by the deterministic forecasts in the diurnal cycle of NOx is removed by the ML models considering lagged measurements and calendar data like hour and weekday, reflecting the influence of local traffic emissions. For O3 at the urban background site, the local photochemistry is not properly accounted for by the relatively coarse Copernicus Atmosphere Monitoring Service ensemble model (CAMS) used here for forecasting O3 but is compensated for using the ML models by taking lagged measurements into account. Through multiple repetitions of the training process, the resulting ML models achieved improvements for all sites and pollutants. For NOx at street canyon sites, mean squared error (MSE) decreased by up to 60%, and seven metrics, such as R2 and mean absolute percentage error (MAPE), exhibited consistent results. The prediction of PM10 is improved significantly at the urban background site, whereas the ML models at street sites have difficulty capturing more information. The prediction accuracy of O3 also modestly increased, with differences between metrics. Further work is needed to reduce deviations between model results and measurements for short periods with relatively high concentrations (peaks) at the street canyon sites. Such peaks can be due to a combination of non-typical emissions and unfavourable meteorological conditions, which are rather difficult to forecast. Furthermore, we show that general models trained using data from selected street sites can improve the deterministic forecasts of NOx at the station not involved in model training. For PM10 this was only possible using more complex LSTM models. An important aspect to consider when choosing ML algorithms is the computational requirements for training the models in the deployment of the system. Tree-based models (RF and XGB) require fewer computational resources and yield comparable performance in comparison to LSTM. Therefore, tree-based models are now implemented operationally in the forecasts of air pollution and health risks in Stockholm. Nevertheless, there is big potential to develop generic models using advanced ML to take into account not only local temporal variation but also spatial variation at different stations.
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