| 1. |
- Ahlberg, Erik, et al.
(författare)
-
"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. |
- Ahlgren-Moritz, Charlotte, et al.
(författare)
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Vägen till samverkanssäkrad utbildning. [1] : Metoder och strategier
- 2016
-
Bok (övrigt vetenskapligt/konstnärligt)abstract
- Universitet och högskolor bidrar till samhällsutvecklingen genom att forskningsbaserad kunskap tillämpas av olika aktörer i samhället. För att möta dagens och morgondagens samhällsutmaningar utgör således kunskapsutbyte och samverkan mellan lärosäten och samhället en värdefull möjlighet. Att ha starka relationer med samhällets aktörer identifieras också som viktigt i utvecklingen av ett internationellt starkt lärosäte.Samverkan i högre utbildning främjar samhällets förändringsförmåga och stärker utbildningens kvalitet, men samverkan förbereder också studenterna för ett livslångt lärande och underlättar övergången mellan utbildning och arbetsliv. Ett lärosäte i nära samverkan med aktörer i samhället är ett relevant lärosäte, det vill säga ett lärosäte som är till nytta för sin omvärld och för sina medarbetare och studenter.Ett grundläggande problem vad gäller möjligheterna att integrera samverkan i akademisk utbildning står att finna i statens fördelning av medel till lärosätena. De statliga medlen utgår nämligen i två separata anslag, ett vardera för de båda huvuduppdragen utbildning och forskning. Samverkan kan sägas ingå i bägge uppdragen. Till skillnad från forskningssamverkan finns det för utbildningssamverkan ingen särskild uppföljning och inte heller några ekonomiska incitament. Utvärdering av forskning och utbildning bör således breddas så att kvalitetsstärkande samverkansinslag också inkluderas i resursfördelningsprinciperna. Statens bristande strukturer för fördelning och uppföljning återspeglas i hur lärosätena fördelar resurser till och följer upp samverkan: lärare ges sällan resurser (i form av särskild tid) för att på ett pedagogiskt genomtänkt sätt kunna inkludera samverkansinslag i undervisningen; samverkan är sällan meriterande eller lönegrundande; och den utbildningssamverkan som bedrivs följs sällan upp – varken på institutions-, fakultets- eller lärosätesnivå. Samma sak kan sägas gälla på nationell nivå – det samverkande lärosätet erhåller inga extra anslag och det bestraffas ej heller för försummelse av detsamma. Att göra samverkan till en integrerad del av utbildningen innebär att samverkan bör ingå i de pedagogiska modeller som lärare använder för att leda studenternas kunskapsutveckling mot de mål som finns angivna i kurs- och utbildningsplaner. Det betyder också att arbetet med samverkan bör inkluderas i processer för styrning, planering och uppföljning av utbildning och undervisning på såväl kurs- och programnivå som på institutions-, fakultets- och lärosätesnivå. Att göra samverkan till en integrerad del av utbildningen är att sträva mot att externa aktörer ska bli en självklar del i den dagliga verksamheten – för studenter såväl som för medarbetare och för de organisationer man samverkar med. För att svenska lärosäten ska ges en realistisk möjlighet att göra samverkan till en integrerad del av utbildningsverksamheten krävs det framför allt följande:att politiker och departement utformar ett fördelningssystem där framgångsrika samverkansinsatser inom utbildningen leder till en förstärkning av resursbasen på lärosätena;att lärosätesledningar tar tydlig ställning för samverkansfrågan i sina strategiska styrdokument och att samverkan införs i lärosätenas kvalitetssäkringssystem för utbildning, samt att lärosätena inför system för att styra och följa upp samverkan i utbildningen på lärosätesövergripande nivå;att ledningen för fakulteter, institutioner eller motsvarande omsätter lärosätets strategiska åtaganden i handlingsplaner och lokala styrdokument samt utformar system för dokumentation, styrning och uppföljning av samverkan i utbildningsprogram;att lärare samt kurs- och programansvariga inför samverkan i utbildningens styrande dokument (t.ex. kurs- och utbildningsplaner) samt i den ordinarie undervisningsverksamheten.Dessutom bör lärosätena – både gemensamt men också vart och ett för sig – införa system och karriärvägar där medarbetares insatser i det vardagliga samverkansarbetet uppmärksammas och belönas.Mot bakgrund av detta kan man konstatera att det är angeläget att lärosätenas strategiska arbete avseende utveckling och uppföljning av samverkan i utbildningen vidareutvecklas. Men, med vilka verktyg, var i verksamheten och på vilka sätt?I följande skrift samlas erfarenheter och goda exempel gjorda inom ramen för ett flerårigt lärosätesövergripande samarbetsprojekt, Samverkanssäkrade utbildningsprogram, där utgångspunkten har varit att identifiera strategier och metoder för att integrera samverkan i utbildningsprogram. Målet har varit att undersöka och beskriva hur samverkan kan vara ett medel som bidrar till att stärka utbildningens kvalitet och relevans, samt ge förslag på hur vägen till samverkanssäkrad utbildning kan se ut.Den centrala slutsatsen är att samverkan, när den är en integrerad del av utbildningen, bidrar till kvalitet och säkerställer att utbildningen blir till nytta för samhället. Det finns också andra vinster med att bedriva ett systematiskt samverkansarbete, till exempel att det leder till pedagogisk utveckling för undervisande personal, att det ökar förutsättningarna för ett utmaningsbaserat lärande med studenten i centrum, att det underlättar övergången från studier till arbetsliv, och att det möjliggör fördjupade relationer med den värld lärosätet finns i. Resan mot samverkanssäkrad utbildning är, med andra ord, mödan väl värd.
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| 3. |
- Ahlgren-Moritz, Charlotte, et al.
(författare)
-
Vägen till samverkanssäkrad utbildning. [2] : Möjligheter och utmaningar
- 2016
-
Bok (övrigt vetenskapligt/konstnärligt)abstract
- Universitet och högskolor bidrar till samhällsutvecklingen genom att forskningsbaserad kunskap tillämpas av olika aktörer i samhället. För att möta dagens och morgondagens samhällsutmaningar utgör således kunskapsutbyte och samverkan mellan lärosäten och samhället en värdefull möjlighet. Att ha starka relationer med samhällets aktörer identifieras också som viktigt i utvecklingen av ett internationellt starkt lärosäte.Samverkan i högre utbildning främjar samhällets förändringsförmåga och stärker utbildningens kvalitet, men samverkan förbereder också studenterna för ett livslångt lärande och underlättar övergången mellan utbildning och arbetsliv. Ett lärosäte i nära samverkan med aktörer i samhället är ett relevant lärosäte, det vill säga ett lärosäte som är till nytta för sin omvärld och för sina medarbetare och studenter.Ett grundläggande problem vad gäller möjligheterna att integrera samverkan i akademisk utbildning står att finna i statens fördelning av medel till lärosätena. De statliga medlen utgår nämligen i två separata anslag, ett vardera för de båda huvuduppdragen utbildning och forskning. Samverkan kan sägas ingå i bägge uppdragen. Till skillnad från forskningssamverkan finns det för utbildningssamverkan ingen särskild uppföljning och inte heller några ekonomiska incitament. Utvärdering av forskning och utbildning bör således breddas så att kvalitetsstärkande samverkansinslag också inkluderas i resursfördelningsprinciperna. Statens bristande strukturer för fördelning och uppföljning återspeglas i hur lärosätena fördelar resurser till och följer upp samverkan: lärare ges sällan resurser (i form av särskild tid) för att på ett pedagogiskt genomtänkt sätt kunna inkludera samverkansinslag i undervisningen; samverkan är sällan meriterande eller lönegrundande; och den utbildningssamverkan som bedrivs följs sällan upp – varken på institutions-, fakultets- eller lärosätesnivå. Samma sak kan sägas gälla på nationell nivå – det samverkande lärosätet erhåller inga extra anslag och det bestraffas ej heller för försummelse av detsamma. Att göra samverkan till en integrerad del av utbildningen innebär att samverkan bör ingå i de pedagogiska modeller som lärare använder för att leda studenternas kunskapsutveckling mot de mål som finns angivna i kurs- och utbildningsplaner. Det betyder också att arbetet med samverkan bör inkluderas i processer för styrning, planering och uppföljning av utbildning och undervisning på såväl kurs- och programnivå som på institutions-, fakultets- och lärosätesnivå. Att göra samverkan till en integrerad del av utbildningen är att sträva mot att externa aktörer ska bli en självklar del i den dagliga verksamheten – för studenter såväl som för medarbetare och för de organisationer man samverkar med. För att svenska lärosäten ska ges en realistisk möjlighet att göra samverkan till en integrerad del av utbildningsverksamheten krävs det framför allt följande:att politiker och departement utformar ett fördelningssystem där framgångsrika samverkansinsatser inom utbildningen leder till en förstärkning av resursbasen på lärosätena;att lärosätesledningar tar tydlig ställning för samverkansfrågan i sina strategiska styrdokument och att samverkan införs i lärosätenas kvalitetssäkringssystem för utbildning, samt att lärosätena inför system för att styra och följa upp samverkan i utbildningen på lärosätesövergripande nivå;att ledningen för fakulteter, institutioner eller motsvarande omsätter lärosätets strategiska åtaganden i handlingsplaner och lokala styrdokument samt utformar system för dokumentation, styrning och uppföljning av samverkan i utbildningsprogram;att lärare samt kurs- och programansvariga inför samverkan i utbildningens styrande dokument (t.ex. kurs- och utbildningsplaner) samt i den ordinarie undervisningsverksamheten.Dessutom bör lärosätena – både gemensamt men också vart och ett för sig – införa system och karriärvägar där medarbetares insatser i det vardagliga samverkansarbetet uppmärksammas och belönas.Mot bakgrund av detta kan man konstatera att det är angeläget att lärosätenas strategiska arbete avseende utveckling och uppföljning av samverkan i utbildningen vidareutvecklas. Men, med vilka verktyg, var i verksamheten och på vilka sätt?I följande skrift samlas erfarenheter och goda exempel gjorda inom ramen för ett flerårigt lärosätesövergripande samarbetsprojekt, Samverkanssäkrade utbildningsprogram, där utgångspunkten har varit att identifiera strategier och metoder för att integrera samverkan i utbildningsprogram. Målet har varit att undersöka och beskriva hur samverkan kan vara ett medel som bidrar till att stärka utbildningens kvalitet och relevans, samt ge förslag på hur vägen till samverkanssäkrad utbildning kan se ut.Den centrala slutsatsen är att samverkan, när den är en integrerad del av utbildningen, bidrar till kvalitet och säkerställer att utbildningen blir till nytta för samhället. Det finns också andra vinster med att bedriva ett systematiskt samverkansarbete, till exempel att det leder till pedagogisk utveckling för undervisande personal, att det ökar förutsättningarna för ett utmaningsbaserat lärande med studenten i centrum, att det underlättar övergången från studier till arbetsliv, och att det möjliggör fördjupade relationer med den värld lärosätet finns i. Resan mot samverkanssäkrad utbildning är, med andra ord, mödan väl värd.
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| 4. |
- Al-Mashhadi, Ammar, et al.
(författare)
-
Changes of arterial pressure following relief of obstruction in adults with hydronephrosis
- 2018
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Ingår i: Upsala Journal of Medical Sciences. - : Uppsala Medical Society. - 0300-9734 .- 2000-1967. ; 123:4, s. 216-224
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Tidskriftsartikel (refereegranskat)abstract
- Background: As much as 20% of all cases of hypertension are associated with kidney malfunctions. We have previously demonstrated in animals and in pediatric patients that hydronephrosis causes hypertension, which was attenuated by surgical relief of the ureteropelvic junction (UPJ) obstruction. This retrospective cohort study aimed to investigate: (1) the proposed link between hydronephrosis, due to UPJ obstruction, and elevated arterial pressure in adults; and (2) if elevated blood pressure in patients with hydronephrosis might be another indication for surgery.Materials and methods: Medical records of 212 patients undergoing surgical management of hydronephrosis, due to UPJ obstruction, between 2000 and 2016 were assessed. After excluding patients with confounding conditions and treatments, paired arterial pressures (i.e. before/after surgery) were compared in 49 patients (35 years old; 95% CI 29–39). Split renal function was evaluated by using mercaptoacetyltriglycine (MAG3) renography before surgical management of the hydronephrotic kidney.Results: Systolic (−11 mmHg; 95% CI 6–15 mmHg), diastolic (−8 mmHg; 95% CI 4–11 mmHg), and mean arterial (-9 mmHg; 95% CI 6–12) pressures were significantly reduced after relief of the obstruction (p < 0.001). Split renal function of the hydronephrotic kidney was 39% (95% CI 37–41). No correlations were found between MAG3 and blood pressure level before surgery or between MAG3 and the reduction of blood pressure after surgical management of the UPJ obstruction.Conclusions: In adults with hydronephrosis, blood pressure was reduced following relief of the obstruction. Our findings suggest that elevated arterial pressure should be taken into account as an indication to surgically correct hydronephrosis.
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| 5. |
- Al-Mashhadi, Ammar Nadhom Farman, et al.
(författare)
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Changes in arterial pressure and markers of nitric oxide homeostasis and oxidative stress following surgical correction of hydronephrosis in children
- 2018
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Ingår i: Pediatric nephrology (Berlin, West). - : Springer. - 0931-041X .- 1432-198X. ; 33:4, s. 639-649
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Tidskriftsartikel (refereegranskat)abstract
- Objective Recent clinical studies have suggested an increased risk of elevated arterial pressure in patients with hydronephrosis. Animals with experimentally induced hydronephrosis develop hypertension, which is correlated to the degree of obstruction and increased oxidative stress. In this prospective study we investigated changes in arterial pressure, oxidative stress, and nitric oxide (NO) homeostasis following correction of hydronephrosis.Methods Ambulatory arterial pressure (24 h) was monitored in pediatric patients with hydronephrosis (n = 15) before and after surgical correction, and the measurements were compared with arterial pressure measurements in two control groups, i.e. healthy controls (n = 8) and operated controls (n = 8). Markers of oxidative stress and NO homeostasis were analyzed in matched urine and plasma samples.Results The preoperative mean arterial pressure was significantly higher in hydronephrotic patients [83 mmHg; 95% confidence interval (CI) 80–88 mmHg] than in healthy controls (74 mmHg; 95% CI 68–80 mmHg; p < 0.05), and surgical correction of ureteral obstruction reduced arterial pressure (76 mmHg; 95% CI 74–79 mmHg; p < 0.05). Markers of oxidative stress (i.e., 11- dehydroTXB2, PGF2α, 8-iso-PGF2α, 8,12-iso-iPF2α-VI) were significantly increased (p < 0.05) in patients with hydronephrosis compared with both control groups, and these were reduced following surgery (p < 0.05). Interestingly, there was a trend for increased NO synthase activity and signaling in hydronephrosis, which may indicate compensatory mechanism(s).Conclusion This study demonstrates increased arterial pressure and oxidative stress in children with hydronephrosis compared with healthy controls, which can be restored to normal levels by surgical correction of the obstruction. Once reference data on ambulatory blood pressure in this young age group become available, we hope cut-off values can be defined for deciding whether or not to correct hydronephrosis surgically.Keywords Blood pressure . Hydronephrosis . Hypertension . Nitric oxide . Oxidative stress . Ureteral obstruction
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| 6. |
- Al-Mashhadi, Ammar Nadhom Farman, et al.
(författare)
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Surgical treatment reduces blood pressure in children with unilateral congenital hydronephrosis
- 2015
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Ingår i: Journal of Pediatric Urology. - : Elsevier BV. - 1477-5131 .- 1873-4898. ; 11:2, s. 91.e1-91.e6
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Tidskriftsartikel (refereegranskat)abstract
- Objective Renal disorders can cause hypertension, but less is known about the influence of hydronephrosis on blood pressure. Hydronephrosis due to pelvo-ureteric junction obstruction (PUJO) is a fairly common condition (incidence in newborns of 0.5-1%). Although hypertensive effects of hydronephrosis have been suggested, this has not been substantiated by prospective studies in humans [1-3]. Experimental studies with PUJO have shown that animals with induced hydronephrosis develop salt-sensitive hypertension, which strongly correlate to the degree of obstruction [4-7]. Moreover, relief of the obstruction normalized blood pressure [8]. In this first prospective study our aim was to study the blood pressure pattern in pediatric patients with hydronephrosis before and after surgical correction of the ureteral obstruction. Specifically, we investigated if preoperative blood pressure is reduced after surgery and if split renal function and renographic excretion curves provide any prognostic information. Patients and methods Twelve patients with unilateral congenital hydronephrosis were included in this prospective study. Ambulatory blood pressure (24 h) was measured preoperatively and six months after surgery. Preoperative evaluations of bilateral renal function by Tc99m-MAG3 scintigraphy, and renography curves, classified according to O'Reilly, were also performed. Results As shown in the summary figure, postoperative systolic (103 +/- 2 mmHg) and diastolic (62 +/- 2 mmHg) blood pressure were significantly lower than those obtained preoperatively (110 +/- 4 and 69 +/- 2 mmHg, respectively), whereas no changes in circadian variation or pulse pressure were observed. Renal functional share of the hydronephrotic kidney ranged from 11 to 55%. There was no correlation between the degree of renal function impairment and the preoperative excretory pattern, or between the preoperative excretory pattern and the blood pressure reduction postoperatively. However, preoperative MAG3 function of the affected kidney correlated with the magnitude of blood pressure change after surgery. Discussion Correction of the obstruction lowered blood pressure, and the reduction in blood pressure appeared to correlate with the degree of renal functional impairment, but not with the excretory pattern. Thus, in the setting of hypertension, it appears that the functional share of the hydronephrotic kidney should be considered an indicator of the need for surgery, whereas the renography curve is less reliable. The strength of the present study is the prospective nature and that ambulatory blood pressure monitoring was used. Future longitudinal prolonged follow-up studies are warranted to confirm the present findings, and to understand if a real nephrogenic hypertension with potential necessity of treatment will develop. Conclusion This novel prospective study in patients with congenital hydronephrosis demonstrates a reduction in blood pressure following relief of the obstruction. Based on the present results, we propose that the blood pressure level should also be taken into account when deciding whether to correct hydronephrosis surgically or not.
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| 7. |
- Aronsson, Mattias, et al.
(författare)
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Cost-effectiveness of endovascular thrombectomy in patients with acute ischemic stroke.
- 2016
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Ingår i: Neurology. - : American Academy of neurology. - 0028-3878 .- 1526-632X. ; 86:11, s. 1053-9
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Tidskriftsartikel (refereegranskat)abstract
- Objective:To evaluate the cost-effectiveness of adding endovascular thrombectomy to standard care in patients with acute ischemic stroke.Methods:The cost-effectiveness analysis of endovascular thrombectomy in patients with acute ischemic stroke was based on a decision-analytic Markov model. Primary outcomes from ESCAPE, Extending the Time for Thrombolysis in Emergency Neurological Deficits-Intra-Arterial (EXTEND-IA), Multicenter Randomized Clinical Trial of Endovascular Treatment for Acute Ischemic Stroke in the Netherlands (MR CLEAN), Endovascular Revascularization With Solitaire Device Versus Best Medical Therapy in Anterior Circulation Stroke Within 8 Hours (REVASCAT), and Solitaire with the Intention for Thrombectomy as Primary Endovascular Treatment for Acute Ischemic Stroke (SWIFT PRIME) along with data from published studies and registries were used in this analysis. We used a health care payer perspective and a lifelong time horizon to estimate costs and effects.Results:The model showed that adding thrombectomy with stent retrievers to guideline-based care (including IV thrombolysis) resulted in a gain of 0.40 life-years and 0.99 quality-adjusted life-years along with a cost savings of approximately $221 per patient. The sensitivity analysis showed that the results were not sensitive to changes in uncertain parameters or assumptions.Conclusions:Adding endovascular treatment to standard care resulted in substantial clinical benefits at low costs. The results were consistent throughout irrespective of whether data from ESCAPE, EXTEND-IA, MR CLEAN, REVASCAT, or SWIFT PRIME were used in this model.
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| 8. |
- Aronsson, Mattias, et al.
(författare)
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Kostnadseffektiviteten av trombektomibehandling vid akut ischemisk stroke
- 2016
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Ingår i: Neurologi i Sverige. - 2000-8538. ; 3
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Tidskriftsartikel (refereegranskat)abstract
- Flera randomiserade studier har visat på mycket goda kortsiktiga medicinska effekter av trombektomibehandling som tillägg till standardbehandling. Frågan återstår dock om den långsiktiga nyttan kan rättfärdiga de höga kostnaderna för denna behandling. Mattias Aronsson, Josefine Persson, Christian Blomstrand, Per Wester och Lars-Åke Levin beskriver här resultaten från sin hälsoekonomiska studie, som publicerades i tidskriften Neurology tidigare i år.
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| 9. |
- Aurand, B., et al.
(författare)
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Manipulation of the spatial distribution of laser-accelerated proton beams by varying the laser intensity distribution
- 2016
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Ingår i: Physics of Plasmas. - : AIP Publishing. - 1089-7674 .- 1070-664X. ; 23:2
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Tidskriftsartikel (refereegranskat)abstract
- We report on a study of the spatial profile of proton beams produced through target normal sheath acceleration using flat target foils and changing the laser intensity distribution on the target front surface. This is done by either defocusing a single laser pulse or by using a split-pulse setup and irradiating the target with two identical laser pulses with variable spatial separation. The resulting proton beam profile and the energy spectrum are recorded as functions of the focal spot size of the single laser pulse and of the separation between the two pulses. A shaping of the resulting proton beam profile, related to both an increase in flux of low-energy protons in the target normal direction and a decrease in their divergence, in one or two dimensions, is observed. The results are explained by simple modelling of rear surface sheath field expansion, ionization, and projection of the resulting proton beam.
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| 10. |
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Barnstugan
- 2015
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- Boken är en del av projektet Barnstugan. Boken redogör för en konstnärlig undersökning av två arkitektoniska projekt från slutet av 60-talet. Husen är ett typdaghemsprojekt för Stockholm stad samt Ingmar Bergmans bostad på Fårö. Husen sammanlänkas av det kontor (Abramsons arkitektkontor) som under samma tid projekterade husen. Genom att se på liknelser och skillnader, fysiska och innehållsliga, vill undersöks relationen mellan kollektiv och individ. Till boken har ett antal personer bjudits in att reflektera kring de tematiker projektet tangerar.
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| 11. |
- Broberg, Thomas, et al.
(författare)
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An electricity market in transition : demand flexibility and preference heterogeneity
- 2015
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- In a recent report to the Swedish Energy Markets Inspectorate (Broberg et al., 2014) consumer behavior and consumer flexibility concerning energy use were analyzed. Two main conclusions were drawn. First, electricity consumption follows a regular pattern over the day, week, and year, which to a large extent reflects household living patterns and climate variations over the year. Second, the average household needs a substantial economic compensation to voluntarily reschedule its electricity use away from peak demand hours. The required compensations were found to be far higher than the economic incentives households face today when exposed to real-time pricing. In addition, it was found that households are more flexible in the use of electricity for heating than in the use of electrical appliances. Finally, households were found to be more flexible during the morning peak hours than during the evening hours. These findings led to the overall conclusion that both the possibilities and incentives are such that we cannot expect any substantial change in energy use patterns from technical reforms that creates incentives for demand response in line with the current price variation on the wholesale market for electricity.In the above-mentioned report we also analyzed people’s attitudes towards information dissemination. We concluded that many households do not wish to have their electricity use scrutinized by experts and other households. We found that people, on average, required a compensation to allow such information sharing. Again, new technologies open for various demand response policies, although it does not necessarily imply substantially higher demand flexibility. New technologies need to be combined with consumer interest to be successful in a market economy.The overall objective of the current report is to further scrutinize consumer behavior and flexibility. The first part focuses on Swedish households’ choice of electricity supplier contracts. Specifically, we analyze what types of households choose a fixed price contract. 1 The choice of contract implicitly reveals a consumer’s flexibility since a fixed price contract works as an insurance against price variation. So, by studying what type of households chose a fixed price contract we are able to infer on which type of households are relatively inflexible. This part of the analysis is policy relevant since it touches on the question of what to expect from real-time pricing reforms. A central question is whether a household who uses relatively more electricity is more likely to have a fixed price contract. If this is the case, future access to real-time pricing and a greater price variation may not be a guarantee for a substantial increase in demand response as important consumers (from a policy perspective) are more likely to insure against such circumstances. From this perspective the market for price insurances (fixed price contracts) is a market for inflexibility.While the analysis above considers the effectiveness of future energy policies to promote demand response, it is also relevant to study the question of how the peak demand problem may develop over time. This question is explicitly addressed in the current report by studying how consumer behavior varies across income levels. The existing literature suggests that electricity consumption is positively related to income, although the income elasticity 2 is fairly small. However, almost all studies concerning income effects have studied aggregate electricity use on monthly or yearly basis. The present study departs from the existing literature by studying how daily household electricity use patterns vary across income levels. This approach is novel since it allows us to analyze how the peak load problem may develop in the future as a result of higher income levels, which is commonly expected.By studying the choice of electricity contracts and by estimating hourly income elasticities, the report approach demand flexibility in an indirect way. In the third analysis of the report we address these issues again, although with a somewhat more direct approach. The choice experiment part in Broberg et al. (2014), which focused on the economic incentives needed in order to change people’s energy consumption in a predefined way, is now deepened. The focus is on how socio-economic factors such as e.g. age, gender, education and income may explain preference heterogeneity among the Swedish population. Energy related factors such as living conditions and heating systems are also considered in the analysis. This analysis will inform us about what types of households are inclined to reschedule their energy use when given relatively small economic incentives, and what household’s that are relatively inflexible and thus require large compensations to change their behavior. We also study preference heterogeneity regarding information dissemination in purpose of anonymous peer comparisons.In the final part of the report we deepen our analysis of households’ demand for information about their own and others electricity use. Besides creating incentives for demand response, new technologies included in the smart grid concept also make it possible for policy makers to use tailored information to help consumers to use energy more efficiently. A number of studies highlight inefficiencies in the households’ use of energy (see e.g. Broberg and Kazukauskas, 2014). One highlighted reality is that people seem to pay little attention to energy issues. Of course, if people pay little attention to the price of electricity, the effectiveness of policy measures that work through the pricechannel is limited. In this part of the report we address four basic questions of great relevance for energy efficiency policies worldwide. The questions are (1) What knowledge do people have about the marginal cost of electricity use in terms of everyday electrical appliances? (2) Are the cost perceptions biased and in what direction? (3) Do inattention to energy issues play a significant role in this bias? (4) Do households want information that may help them de-bias their perceptions about energy costs and use?The report is structured such that section 2 gives a brief background on the issues analyzed in the report. The following sections correspond to the issues outlined in the introduction. Section 7 works to tie the analyses together and conclude our results
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| 12. |
- Brunström, Mattias, et al.
(författare)
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From efficacy in trials to effectiveness in clinical practice : The Swedish Stroke Prevention Study
- 2016
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Ingår i: Blood Pressure. - : Informa UK Limited. - 0803-7051 .- 1651-1999. ; 25:4, s. 206-211
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Tidskriftsartikel (refereegranskat)abstract
- Blood pressure treatment has shown great efficacy in reducing cardiovascular events in randomized controlled trials. If this is effective in reducing cardiovascular disease in the general population, is less studied. Between 2001 and 2009 we performed an intervention to improve blood pressure control in the county of Vasterbotten, using Sodermanland County as a control. The intervention was directed towards primary care physicians and included lectures on blood pressure treatment, a computerized decision support system with treatment recommendations, and yearly feed back on hypertension control. Each county had approximately 255000 inhabitants. Differences in age and incidence of cardiovascular disease were small. During follow-up, more than 400000 patients had their blood pressure recorded. The mean number of measurements was eight per patient, yielding a total of 3.4 million blood pressure recordings. The effect of the intervention will be estimated combining the blood pressure data collected from the electronic medical records, with data on stroke, myocardial infarction and mortality from Swedish health registers. Additional variables, from health registers and Statistics Sweden, will be collected to address for confounders. The blood pressure data collected within this study will be an important asset for future epidemiological studies within the field of hypertension.
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| 13. |
- Carlström, Mattias, et al.
(författare)
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Cross-talk Between Nitrate-Nitrite-NO and NO Synthase Pathways in Control of Vascular NO Homeostasis
- 2015
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Ingår i: Antioxidants and Redox Signaling. - : Mary Ann Liebert Inc. - 1523-0864 .- 1557-7716. ; 23:4, s. 295-306
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Tidskriftsartikel (refereegranskat)abstract
- Aims: Inorganic nitrate and nitrite from endogenous and dietary sources have emerged as alternative substrates for nitric oxide (NO) formation in addition to the classic L-arginine NO synthase (NOS)-dependent pathway. Here, we investigated a potential cross-talk between these two pathways in the regulation of vascular function. Results: Long-term dietary supplementation with sodium nitrate (0.1 and 1mmol kg(-1) day(-1)) in rats caused a reversible dose-dependent reduction in phosphorylated endothelial NOS (eNOS) (Ser1177) in aorta and a concomitant increase in phosphorylation at Thr495. Moreover, eNOS-dependent vascular responses were attenuated in vessels harvested from nitrate-treated mice or when nitrite was acutely added to control vessels. The citrulline-to-arginine ratio in plasma, as a measure of eNOS activity, was reduced in nitrate-treated rodents. Telemetry measurements revealed that a low dietary nitrate dose reduced blood pressure, whereas a higher dose was associated with a paradoxical elevation. Finally, plasma cyclic guanosine monophosphate increased in mice that were treated with a low dietary nitrate dose and decreased with a higher dose. Innovation and Conclusions: These results demonstrate the existence of a cross-talk between the nitrate-nitrite-NO pathway and the NOS-dependent pathway in control of vascular NO homeostasis. Antioxid. Redox Signal. 23, 295-306.
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| 14. |
- Dawkins, Elena, 1984-
(författare)
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Sustainable consumption for policymakers: measuring, learning and acting
- 2019
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Current patterns and levels of consumption are a key driver of unsustainable resource use and pollution, which contributes to global environmental degradation. Rapid reductions in environmental pressures are required to avoid irreversible loss of fragile ecosystems and social and economic crises. Consumption must become sustainable. Governments have an essential role to play in delivering this. The aim of this thesis is to examine three aspects of the policymaking process on sustainable consumption – measuring, learning and acting – and the links between them. Each aspect has a linked objective.Measuring: Assess existing and novel techniques for calculating the environmental pressures of consumption that enable government to measure and monitor a country’s progress towards sustainable consumptionLearning: Determine whether – and, if so, how – consumption-based indicators might better support policymaker learning on sustainable consumptionActing: Identify ways in which governments can enhance their actions to support sustainable consumptionThe research is presented in six papers and organised in three parts: one for each objective. Parts 1 and 2 investigate current and future opportunities for policymakers to measure the environmental pressures linked to their country’s consumption, what these mean for achieving sustainable consumption and whether consumption-based indicators support learning about sustainable consumption. These parts are based on the Swedish experience of sustainable consumption. Part 3 examines various sustainable consumption interventions and what these could mean for government action in the future. This part draws on examples from several countries. Qualitative and quantitative methods are used to answer these questions. These comprise systematic review and mapping, macro-environment economic modelling and analysis, interviews, workshops and focus groups.The results provide a number of insights. First, novel consumption-based measurements for Sweden highlight the scale of the challenge involved in achieving sustainable consumption and the importance of increasing the policy applicability of indicators. Second, while indicators provide some learning for policymakers, their contribution to changing existing practices and navigating political or institutional barriers is limited. The learning potential of indicators is constrained by institutional environments. Instead, learning must be structured and enabled by institutions. Third, with regard to the actions studied, increased government involvement appears a necessary and, to some actors, desirable option. Nonetheless, a number of barriers to and enabling factors for policy action to promote sustainable consumption must be considered. In terms of the connections between the three elements of measuring, learning and acting, what might first appear to be a linear relationship is in reality far more complex. Measurement does not necessarily lead to learning – and learning is not always followed by action. Policymakers act without the level of knowledge they would like while indicators remain unused and, in some cases, are even rejected. Learning comes from practitioners’ involvement in action, as well as research into the actions themselves, the problem and solutions. Understanding government efforts on measuring, learning and action to promote sustainable consumption offers insights into how these multiple factors might contribute, separately and together, to more sustainable consumption.
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| 15. |
- Denny, Michael, et al.
(författare)
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Interaction between Fuel Jets and Prevailing Combustion During Closely-Coupled Injections in an Optical LD Diesel Engine
- 2019
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Ingår i: SAE Technical Paper : Automotive - Automotive. - 400 Commonwealth Drive, Warrendale, PA, United States : SAE International. - 0148-7191.
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Konferensbidrag (refereegranskat)abstract
- Two imaging techniques are used to investigate the interaction between developed combustion from earlier injections and partially oxidized fuel (POF) ofa subsequent injection. The latter is visualized by using planar laser induced fluorescence (PLIF) of formaldehyde and poly-cyclic aromatic hydrocarbons. High speed imaging captures the natural luminescence (NL) of the prevailing combustion. Three different fuel injection strategies are studied. One strategy consists of two pilot injections, with modest separations after each, followed by single main and post injections. Both of the other two strategies have threepilots followed by single main and post injections. The separations after the second and third pilots are several times shorter than in the reference case (making them closelycoupled). The closely-coupled cases have more linear heatrelease rates (HRR) which lead to much lower combustion noise levels. For all cases, POF is detected during the very weak HRR before the notable combustion of the first pilot injection’s fuel. When the subsequent fuel injections overlapwith a local decrease in HRR, the prevailing combustion is to some degree extinguished during these phases. This is seen via the NL signal being replaced by the POF signal, indicating that hotter combustion products are being replaced by cooler ones. When the NL and POF regions spatially overlap, the POF signal decreases, and there is no injection, this marks the further oxidation of the POF into hotter combustion products. This extinguishing phenomenon can, to a lesser extent than closely-coupling, affect the combustion noise by affecting the magnitude of the local dips in the HRR, which via its influence on the pressure trace, affects combustion noise.
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| 16. |
- Denny, Michael, et al.
(författare)
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Optical Investigation on the Combustion Process Differences between Double-Pilot and Closely-Coupled Triple-Pilot Injection Strategies in a LD Diesel Engine
- 2019
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Ingår i: International Powertrains, Fuels & Lubricants Meeting. - 400 Commonwealth Drive, Warrendale, PA, United States : SAE International. - 0148-7191. ; 2019-January
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Konferensbidrag (refereegranskat)abstract
- The combustion processes of three injection strategies in a light-duty (LD) diesel engine at a medium load point are captured with a high speed video camera. A double-pilot/main/single-post injection strategy representative of a LD Euro 6 calibration is considered as the reference. There is a modest temporal spacing (dwell) after the first pilot (P1) and second pilot (P2). A second strategy, "A," adds a third pilot (P3). The dwell after both P2 and P3 are several times shorter than in the reference strategy. A third strategy, "B," further reduces all dwells. Each injection has its own associated local peak in the heat release rate (HRR) following some ignition delay. Between these peaks lie local minima, or dips. In all three cases, the fuel from P1 combusts as a propagating premixed flame. For all strategies, the ignition of P2 primarily occurs at its interface with the existing combustion regions. Extinguishing of the prevailing combustion by the fuel jets of later injections is noted in all strategies. This phenomenon is confirmed by comparing the timing of each fuel injection with the dips in the HRR and spatial luminescence over time. These dips after each injection are larger than would be expected by the cooling effect of the injected fuel alone. Furthermore, not all dips in the HRR are the result of this extinguishing, and it would not have been possible to determine if the dips are due to this extinguishing or a simple exhaustion of available fuel without this optical investigation. Even if the precise hydraulic injection timing can be known, knowledge of the spatial relationship of the injected fuel and prevailing combustion is necessary.
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| 17. |
- Dobsicek Trefna, Hana, 1979, et al.
(författare)
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Multifrequency approach in hyperthermia treatment planning: Impact of frequency on SAR distribution in head and neck
- 2017
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Ingår i: 2017 11th European Conference on Antennas and Propagation, EUCAP 2017. ; , s. 3710-3712
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Konferensbidrag (refereegranskat)abstract
- Addition of hyperthermia to radiotherapy has been shown beneficial in management of many types of cancer [1], including Head and Neck tumors [2]. The objective of hyperthermia treatment is to raise the temperature in the tumor to a therapeutic level 40-44°C for typically 60 minutes to achieve cell death or render the cells more sensitive to ionizing radiation and chemical toxins. In our work, we aim to develop H&N applicator that is capable of modifying the focus size according to tumor position and volume. The system consists of a number of antennas placed around a patient, relying on a constructive wave interference to selectively heat the tumour. The spatial control of the foci spot and thus the quality of hyperthermia treatment can be controled by varying operational frequency in addition to amplitude and phase optimization. Due to different wavelengths, treatment associated hot spots often appear at different locations. In conjunction with cooling effect of the blood, the multi-frequency system have potential to achieve higher tumor temperature with 'same' constraints on hot spots. In this paper we investigated if combination of treatment plans utilizing sequential application of various frequencies is superior to the heating with single frequency settings.
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| 18. |
- Ehlers, Sarah, et al.
(författare)
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Assessing Error Correlations in Remote Sensing-Based Estimates of Forest Attributes for Improved Composite Estimation
- 2018
-
Ingår i: Remote Sensing. - : MDPI AG. - 2072-4292. ; 10
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Tidskriftsartikel (refereegranskat)abstract
- Today, non-expensive remote sensing (RS) data from different sensors and platforms can be obtained at short intervals and be used for assessing several kinds of forest characteristics at the level of plots, stands and landscapes. Methods such as composite estimation and data assimilation can be used for combining the different sources of information to obtain up-to-date and precise estimates of the characteristics of interest. In composite estimation a standard procedure is to assign weights to the different individual estimates inversely proportional to their variance. However, in case the estimates are correlated, the correlations must be considered in assigning weights or otherwise a composite estimator may be inefficient and its variance be underestimated. In this study we assessed the correlation of plot level estimates of forest characteristics from different RS datasets, between assessments using the same type of sensor as well as across different sensors. The RS data evaluated were SPOT-5 multispectral data, 3D airborne laser scanning data, and TanDEM-X interferometric radar data. Studies were made for plot level mean diameter, mean height, and growing stock volume. All data were acquired from a test site dominated by coniferous forest in southern Sweden. We found that the correlation between plot level estimates based on the same type of RS data were positive and strong, whereas the correlations between estimates using different sources of RS data were not as strong, and weaker for mean height than for mean diameter and volume. The implications of such correlations in composite estimation are demonstrated and it is discussed how correlations may affect results from data assimilation procedures.
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| 19. |
- Eriksson, Mattias, et al.
(författare)
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Mapping of food waste quantification methodologies in the food services of Swedish municipalities
- 2018
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Ingår i: Resources, Conservation and Recycling. - : ELSEVIER SCIENCE BV. - 0921-3449 .- 1879-0658. ; 137, s. 191-199
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Tidskriftsartikel (refereegranskat)abstract
- Since food waste valorisation measures, like energy recovery, have limited possibilities to fully recover the resources invested in food production, there is a need to prevent food waste. Prevention is most important at the end of the value chain, where most sub-processes have already taken place, like in catering facilities. In Sweden, the public catering sector serves a large number of meals through municipal organisations, including schools, preschools and elderly care homes. Many of these organisations quantify food waste, but since Sweden has 290 municipalities with a high degree of independence, the possible variation is significant. This study therefore investigated how food waste is quantified, in order to help formulate a national standard for food waste quantification. Mapping of food waste quantification practices was conducted using a questionnaire and follow-up telephone calls, achieving a response rate of 93%. Of the 290 Swedish municipalities, 55% replied that they quantify food waste on central level. The most common practice at present is to quantify plate- and serving waste from school lunches during two weeks per year, and to compile waste data in spreadsheets and compare the values against the number of plates used, giving a result in grams per portion served. There are many similarities between municipalities, so there is great potential to implement a common standard that many municipalities already fulfil. This is important in order to gain acceptance and fast implementation, thereby speeding up the process of establishing a benchmark for food waste in the Swedish public sector catering sector.
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| 20. |
- Eriksson, Mattias, et al.
(författare)
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Quantification of food waste in public catering services : A case study from a Swedish municipality
- 2017
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Ingår i: Waste Management. - : Elsevier BV. - 0956-053X .- 1879-2456. ; 61, s. 415-422
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Tidskriftsartikel (refereegranskat)abstract
- Food waste is a major problem that must be reduced in order to achieve a sustainable food supply chain. Since food waste valorisation measures, like energy recovery, have limited possibilities to fully recover the resources invested in food production, there is a need to prevent food waste. Prevention is most important at the end of the value chain, where the largest number of sub-processes have already taken place and occur in vain if the food is not used for its intended purpose, i.e. consumption. Catering facilities and households are at the very end of the food supply chain, and in Sweden the public catering sector serves a large number of meals through municipal organisations, including schools, preschools and elderly care homes. Since the first step in waste reduction is to establish a baseline measurement in order to identify problems, this study sought to quantify food waste in schools, preschools and elderly care homes in one municipality in Sweden. The quantification was conducted during three months, spread out over three semesters, and was performed in all 30 public kitchen units in the municipality of Sala. The kitchen staff used kitchen scales to quantify the mass of wasted and served food divided into serving waste (with sub-categories), plate waste and other food waste. The food waste level was quantified as 75 g of food waste per portion served, or 23% of the mass of food served. However, there was great variation between kitchens, with the waste level ranging from 33 g waste per portion served (13%) to 131 g waste per portion served (34%). Wasted food consisted of 64% serving waste, 33% plate waste and 3% other food waste. Preschools had a lower waste level than schools, possibly due to preschool carers eating together with the children. Kitchens that received warm food prepared in another kitchen (satellite kitchens) had a 42% higher waste level than kitchens preparing all food themselves (production units), possibly due to the latter having higher flexibility in cooking the right amount of food and being able to chill and save surplus food. The large variation between kitchens indicates that they have different causes of food waste, but also different opportunities to reduce it. Detailed waste quantification for each kitchen can therefore be the first step in the process of waste reduction.
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| 21. |
- Eriksson, Mattias, et al.
(författare)
-
The tree structure : A general framework for food waste quantification in food services
- 2018
-
Ingår i: Resources, Conservation and Recycling. - : Elsevier BV. - 0921-3449 .- 1879-0658. ; 130, s. 140-151
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Tidskriftsartikel (refereegranskat)abstract
- Food waste in the food services industry has been identified as an important unsustainability hotspot, but standardised methods for food waste quantification are lacking. Existing studies on waste quantity assessments have several limitations, such as short and infrequent quantifications times, large methodological variations ranging from physical measurements to visual observations, and lack of comparability across catering unit types. Since lack of comparable waste figures can lead to error-prone analysis, a general framework is needed for waste quantification in food services. This paper presents one such framework that allows data comparisons when overlapping observations are included. The framework was tested in six case studies in professional (public and private) catering units in Sweden. Data were collected from different schools, elderly care homes and hotels and fitted into the framework. The results from these case studies indicate that the framework enables catering units to focus waste quantification on their individual problem areas. It also provides the possibility to extend waste quantification over time without any loss of generalisability. A graphical representation of the framework fits the traditional tree structure and was found to act as a suitable foundation for food waste quantification in food services by structuring collected data. In order to fully utilise the potential of the tree structure, it should be supplemented with precise definitions to create a catering food waste quantification standard.
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| 22. |
- Fatehi, Hesameddin, et al.
(författare)
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Effects of In-Cylinder Flow Structures on Soot Formation and Oxidation in a Swirl-Supported Light-Duty Diesel Engine
- 2019
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Ingår i: 14th International Conference on Engines & Vehicles: Technical paper. - 400 Commonwealth Drive, Warrendale, PA, United States : SAE International. - 0148-7191.
-
Konferensbidrag (refereegranskat)abstract
- In this paper, computation fluid dynamics (CFD) simulations are performed to describe the effect of in-cylinder flow structures on the formation and oxidation of soot in a swirl-supported light-duty diesel engine. The focus of the paper is on the effect of swirl motion and injection pressure on late cycle soot oxidation. The structure of the flow at different swirl numbers is studied to investigate the effect of varying swirl number on the coherent flow structures. These coherent flow structures are studied to understand the mechanism that leads to efficient soot oxidation in late cycle. Effect of varying injection pressure at different swirl numbers and the interaction between spray and swirl motions are discussed. The complexity of diesel combustion, especially when soot and other emissions are of interest, requires using a detailed chemical mechanism to have a correct estimation of temperature and species distribution. In this work, Representative Interactive Flamelets (RIF) method is employed to describe the chemical reactions, ignition, flame propagation and emissions in the engine. The CFD simulations are validated using experimental measurement of light-duty diesel engine at two different loads. A good agreement is achieved between the model results and the pressure, heat release rates and emissions from the experiment. These cases are considered as the base-line for the parameter study cases.
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| 23. |
- Filippov, Stanislav, et al.
(författare)
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Strongly polarized quantum-dot-like light emitters embedded in GaAs/GaNAs core/shell nanowires
- 2016
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Ingår i: Nanoscale. - : Royal Society of Chemistry. - 2040-3364 .- 2040-3372. ; 8:35, s. 15939-15947
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Tidskriftsartikel (refereegranskat)abstract
- Recent developments in fabrication techniques and extensive investigations of the physical properties of III-V semiconductor nanowires (NWs), such as GaAs NWs, have demonstrated their potential for a multitude of advanced electronic and photonics applications. Alloying of GaAs with nitrogen can further enhance the performance and extend the device functionality via intentional defects and heterostructure engineering in GaNAs and GaAs/GaNAs coaxial NWs. In this work, it is shown that incorporation of nitrogen in GaAs NWs leads to formation of three-dimensional confining potentials caused by short-range fluctuations in the nitrogen composition, which are superimposed on long-range alloy disorder. The resulting localized states exhibit a quantum-dot like electronic structure, forming optically active states in the GaNAs shell. By directly correlating the structural and optical properties of individual NWs, it is also shown that formation of the localized states is efficient in pure zinc-blende wires and is further facilitated by structural polymorphism. The light emission from these localized states is found to be spectrally narrow (similar to 50-130 mu eV) and is highly polarized (up to 100%) with the preferable polarization direction orthogonal to the NW axis, suggesting a preferential orientation of the localization potential. These properties of self-assembled nano-emitters embedded in the GaNAs-based nanowire structures may be attractive for potential optoelectronic applications.
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| 24. |
- Fraser, Magdalena
(författare)
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People of the Dolmens and Stone Cists : An archaeogenetic Investigation of Megalithic Graves from the Neolithic Period on Gotland
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- The study of ancient genomics of pre-historic human remains has in recent years offered unprecedented knowledge regarding pre-historic migration and population structure on the European continent which has fundamentally altered the current views in the archaeological community. However, the merging of the two fields, archaeology and genetics, is still in its infancy and much work is still needed in order for these fields to integrate. In this thesis I explore how genetic analyses, in combination with contextual radiocarbon dating and isotopic analyses for diet and mobility can be used to investigate demographic events on a local and regional level. This is done through the investigation of people buried in five previously excavated megalithic tombs on the Island of Gotland dated to the Neolithic period. I present the genomic population structure and archaeological background for the pre-historic European reference data and show how this is used to investigate population continuity, demographic shifts, cultural duality, and admixture for local and regional contexts. I present new data and explore the Strontium-baseline for the Gotland biosphere which is used for the mobility analyses. I show that mitochondrial haplogroup data is especially useful in combination with isotopic data, and radiocarbon dating for investigation of demographic shifts on a larger scale. I also show that genomic data gives unique insights into the individuals’ life history which, together with the established demographic background allows for fine scale investigation of population demographic events within and between different archaeological contexts. Finally I show that the different Neolithic contexts on Gotland to a large extent involves immigration of new groups to the island, and that the contextual breaks seen in the archaeological record during the Neolithic period are connected with cultural and population demographic shifts. This dissertation demonstrates that genomic analyses, in combination with archaeology and isotopic analyses, as well as contextual osteological analyses and radiocarbon dating, present unique insights into the life history of the actual people who lived the lives we try to understand.
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| 25. |
- Gao, Xiang, et al.
(författare)
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Adenosine A1 receptor-dependent and independent pathways in modulating renal vascular responses to angiotensin II
- 2015
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Ingår i: Acta Physiologica. - : Wiley. - 1748-1708 .- 1748-1716. ; 213:1, s. 268-276
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Tidskriftsartikel (refereegranskat)abstract
- AIM: Renal afferent arterioles are the effector site for autoregulation of glomerular perfusion and filtration. There is synergistic interaction between angiotensin II (ANG II) and adenosine (Ado) in regulating arteriolar contraction, however, the mechanisms are not clear. In this context, this study investigated the contribution of A1 receptor dependent and independent signaling mechanisms.METHODS: Isolated perfused afferent arterioles from transgenic mice (A1+/+ and A1-/-) were used for vascular reactivity studies. Cultured vascular smooth muscle cells (VSMC) were used for phosphorylation studies of signaling proteins that induce arteriolar contraction.RESULTS: Maximal arteriolar contraction to ANG II was attenuated in A1-/- (22%) compared with A1+/+ (40%). Simultaneous incubation with low dose Ado (10-8 mol/L) enhanced ANG II-induced contraction in A1+/+ (58%), but also in A1-/- (42%). An Ado transporter inhibitor (NBTI) abolished this synergistic effect in A1-/-, but not in wild-type mice. Incubation with Ado+ANG II increased p38 phosphorylation in aortic VSMC from both genotypes, but treatment with NBTI only blocked phosphorylation in A1-/-. Combination of ANG II+Ado also increased MLC phosphorylation in A1+/+ but not significantly in A1-/-, and NBTI had no effects. In agreement, Ado+ANG II-induced phosphorylation of p38 and MLC in rat preglomerular VSMC was not affected by NBTI. However, during pharmacological inhibition of the A1 receptor simultaneous treatment with NBTI reduced phosphorylation of both p38 and MLC to control levels.CONCLUSION: Interaction between ANG II and Ado in VSMC normally involves A1 receptor signaling, but this can be compensated by receptor independent actions that phosphorylate p38 MAPK and MLC.
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