| 1. |
- Carlsson, Axel C, et al.
(author)
-
Growth differentiation factor 15 (GDF-15) is a potential biomarker of both diabetic kidney disease and future cardiovascular events in cohorts of individuals with type 2 diabetes : a proteomics approach
- 2020
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In: Upsala Journal of Medical Sciences. - : Uppsala Medical Society. - 0300-9734 .- 2000-1967. ; 25:1, s. 37-43
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Journal article (peer-reviewed)abstract
- Background: Diabetic kidney disease (DKD) is a leading risk factor for end-stage renal disease and is one of the most important risk factors for cardiovascular disease in patients with diabetes. It is possible that novel markers portraying the pathophysiological underpinning processes may be useful.Aim: To investigate the associations between 80 circulating proteins, measured by a proximity extension assay, and prevalent DKD and major adverse cardiovascular events (MACE) in type 2 diabetes.Methods: We randomly divided individuals with type 2 diabetes from three cohorts into a two-thirds discovery and one-third replication set (total n = 813, of whom 231 had DKD defined by estimated glomerular filtration rate <60 mg/mL/1.73 m2 and/or urinary albumin-creatinine ratio ≥3 g/mol). Proteins associated with DKD were also assessed as predictors for incident major adverse cardiovascular events (MACE) in persons with DKD at baseline.Results: Four proteins were positively associated with DKD in models adjusted for age, sex, cardiovascular risk factors, glucose control, and diabetes medication: kidney injury molecule-1 (KIM-1, odds ratio [OR] per standard deviation increment, 1.65, 95% confidence interval [CI] 1.27-2.14); growth differentiation factor 15 (GDF-15, OR 1.40, 95% CI 1.16-1.69); myoglobin (OR 1.57, 95% CI 1.30-1.91), and matrix metalloproteinase 10 (MMP-10, OR 1.43, 95% CI 1.17-1.74). In patients with DKD, GDF-15 was significantly associated with increased risk of MACE after adjustments for baseline age, sex, microalbuminuria, and kidney function and (59 MACE events during 7 years follow-up, hazard ratio per standard deviation increase 1.43 [95% CI 1.03-1.98]) but not after further adjustments for cardiovascular risk factors.Conclusion: Our proteomics approach confirms and extends previous associations of higher circulating levels of GDF-15 with both micro- and macrovascular disease in patients with type 2 diabetes. Our data encourage additional studies evaluating the clinical utility of our findings.
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| 2. |
- Nowak, Christoph, et al.
(author)
-
Multiplex proteomics for prediction of major cardiovascular events in type 2 diabetes
- 2018
-
In: Diabetologia. - : SPRINGER. - 0012-186X .- 1432-0428. ; 61:8, s. 1748-1757
-
Journal article (peer-reviewed)abstract
- Aims/hypothesis Multiplex proteomics could improve understanding and risk prediction of major adverse cardiovascular events (MACE) in type 2 diabetes. This study assessed 80 cardiovascular and inflammatory proteins for biomarker discovery and prediction of MACE in type 2 diabetes. Methods We combined data from six prospective epidemiological studies of 30-77-year-old individuals with type 2 diabetes in whom 80 circulating proteins were measured by proximity extension assay. Multivariable-adjusted Cox regression was used in a discovery/replication design to identify biomarkers for incident MACE. We used gradient-boosted machine learning and lasso regularised Cox regression in a random 75% training subsample to assess whether adding proteins to risk factors included in the Swedish National Diabetes Register risk model would improve the prediction of MACE in the separate 25% test subsample. Results Of 1211 adults with type 2 diabetes (32% women), 211 experienced a MACE over a mean (+/- SD) of 6.4 +/- 2.3 years. We replicated associations (< 5% false discovery rate) between risk of MACE and eight proteins: matrix metalloproteinase (MMP)-12, IL-27 subunit alpha (IL-27a), kidney injury molecule (KIM)-1, fibroblast growth factor (FGF)-23, protein S100-A12, TNF receptor (TNFR)-1, TNFR-2 and TNF-related apoptosis-inducing ligand receptor (TRAIL-R)2. Addition of the 80-protein assay to established risk factors improved discrimination in the separate test sample from 0.686 (95% CI 0.682, 0.689) to 0.748 (95% CI 0.746, 0.751). A sparse model of 20 added proteins achieved a C statistic of 0.747 (95% CI 0.653, 0.842) in the test sample. Conclusions/interpretation We identified eight protein biomarkers, four of which are novel, for risk of MACE in community residents with type 2 diabetes, and found improved risk prediction by combining multiplex proteomics with an established risk model. Multiprotein arrays could be useful in identifying individuals with type 2 diabetes who are at highest risk of a cardiovascular event.
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| 3. |
- Johnson, Tomas, 1979, et al.
(author)
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A Multi-Scale Simulation Method for the Prediction of Edge Wicking in Multi-Ply Paperboard
- 2015
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In: Nordic Pulp and Paper Research Journal. - 2000-0669 .- 0283-2631. ; 30:4, s. 640-650
-
Journal article (peer-reviewed)abstract
- When liquid packaging board is made aseptic in the filling machine the unsealed edges of the board are exposed to a mixture of water and hydrogen peroxide. A high level of liquid penetration may lead to aesthetic as well as functional defects. To be able to make a priori predictions of the edge wicking properties of a certain paperboard material is therefore of great interest to the paper industry as well as to packaging manufacturers. In this paper an extended multi-scale model of edge wicking in multi-ply paperboard is presented. The geometric and physical properties of the paperboard are modeled on the micro-scale, and include fillers and fines. The absolute air permeabilities and pore size distributions are validated with experimental and tomographic values. On the macro-scale random porosity and sizing distributions, time and sizing dependent contact angles, and inter-ply dependence are modeled. Arbitrary shapes of the paperboard are handled through an unstructured 3D surface mesh. Stationary and transient edge wicking simulations are validated against experiments with excellent agreement. The simulations show that the diffusive menisci between the liquid and air phases together with the two-ply model is necessary to achieve good agreement with the transient edge wicking experiments.
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| 4. |
- Nilsson, Jan-Eric, 1952-, et al.
(author)
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Kontraktet styr : översikt av kvantitativa produktivitetstudier gällande byggande av transportinfrastruktur
- 2019
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Reports (other academic/artistic)abstract
- Trafikverkets huvudfokus är framåtblickande på den kommande verksamheten. Det handlar om att identifiera vilka projekt som ska prioriteras i planeringsarbetet och hur projekt ska genomföras på bästa sätt. Ett sådant perspektiv är inte fel men underlättas av en kunskap av vad som tidigare gjorts. Det är arbetskrävande att följa upp den verksamhet som har bedrivs och att ställa resultatet, entreprenörernas arbete, mot kostnaderna för att åstadkomma dessa resultat. Uppföljningsarbetet av produktivitet över tid och nyttjandet av sådan kunskap har förbättringspotential inom Trafikverket.Huvudsyftet med detta notat har varit att med stöd av internationell litteratur identifiera analyser som skulle kunna genomföras också i Sverige. Ett antal exempel på sådana analyser har också getts.Genomgången visar att det fortfarande återstår ett betydande arbete för att kunna genomföra kvantitativa analyser utan en omfattande manuell bearbetning. En sådan arbetsinsats behöver emellertid inte vara omfattande eller svår. Den primära kvarstående uppgiften är att skapa kopplingar mellan de olika databaser som redan existerar samt att säkerställa att dokument frångenomförandeprocessen existerar i digital form och sparas.Ett sådant arbete kommer möjliggöra flera analyser av intresse för såväl Trafikverket som för det internationella forskarsamhället. I avsaknad av ett sådant arbete kommer Trafikverket inte heller i framtiden att kunna redovisa produktivitetsutvecklingen i verksamheten på ett transparent sätt. Därmed inte heller att identifiera lyckade exempel på genomförandet av projekt för att sprida informationen och därmed uppnå det av regeringen uppställda målet.
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| 5. |
- Nilsson, Jan-Eric, 1952-, et al.
(author)
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Kostnadsöverskridande i Trafikverkets entreprenadkontrakt
- 2019
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Reports (other academic/artistic)abstract
- Trafikverket har regeringens uppdrag att verka för en ökad produktivitet i anläggningsbranschen. VTI bistår Trafikverket i detta arbete. I denna rapport redovisas de skillnader som finns mellan det pris som fastställs i ett entreprenadkontrakt mellan Trafikverket och det företag som fått i uppdrag att genomföra en verksamhet och slutkostnaden för uppdraget. 776 kontrakt som avser entreprenader inom både väg- och järnvägssektorn och såväl investeringar som underhållsåtgärder och som kostar mer än 10 miljoner kronor, ingår i materialet.Statistiska tester visar bland annat att risken för kostnadsöverskridanden är mycket stor och något högre för järnvägskontrakt (94 procents sannolikhet) än för vägkontrakt (86 procent). Slutkostnaden för vägkontrakt överskrider kontraktssumman med 20 procent vilket är signifikant lägre än för järnvägskontrakt där slutkostnaden i genomsnitt är 32 procent högre.
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| 6. |
- Nilsson, Jan-Eric, 1952-, et al.
(author)
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Produktivitet i bygg- och anläggningssektorn
- 2020
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Reports (other academic/artistic)abstract
- Produktiviteten i bygg- och anläggningsbranschen ökar väsentligt långsammare än inom andra delar av samhället. Ett syfte med denna rapport är att undersöka om denna observation är specifik för svenska förhållanden. Den internationella jämförelse som görs av information från motsvarigheten till de svenska nationalräkenskaperna visar att utvecklingen i Sverige inte är systematiskt annorlunda än i ett antal andra länder. Problemet med svag produktivitetsutveckling i branschen tycks därför vara generellt.Med denna utgångspunkt behandlas i rapporten förhållanden som fördjupar förståelsen av eftersläpningen. Bland annat görs en bedömning av i vilken utsträckning utvecklingen beror på ändrade inputpriser, ändrade mängder input eller på en kombination av dessa förhållanden. En diskussion förs också kring vilken kostnadsindexering som ska användas för att följa kostnads- eller produktivitetsutvecklingen över tid. En slutsats är att konsumentprisindex bör användas för att jämföra utvecklingen i bygg- och anläggningssektorn med utvecklingen i samhället som helhet. En annan slutsats är att dagens tillvägagångssätt för att mäta pris- och produktivitetsutveckling i branschen har problem med hanteringen av kvalitetsförändringar. En del av den negativa trenden kan sannolikt hänföras till denna förklaring.Rapporten belyser också möjligheterna att använda mikrodata för att belysa tänkbara förklaringar. Med detta avses de analyser som baseras på de kontrakt som skrivs mellan beställare (till exempel Trafikverket) och de entreprenörer som utför nybyggnation och underhåll av infrastruktur. Exempel ges på hur denna typ av ansats kan användas för att fördjupa förståelsen av den svaga produktivitetsutvecklingen och därmed också att ge förslag till förändringar av verksamhetens utformning för att på sikt stärka branschens utveckling.
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| 7. |
- Salihovic, Samira, Associate Senior Lecturer, 1985-, et al.
(author)
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Identification and validation of a blood- based diagnostic lipidomic signature of pediatric inflammatory bowel disease
- 2024
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In: Nature Communications. - : Springer Nature. - 2041-1723. ; 15:1
-
Journal article (peer-reviewed)abstract
- Improved biomarkers are needed for pediatric inflammatory bowel disease. Here we identify a diagnostic lipidomic signature for pediatric inflammatory bowel disease by analyzing blood samples from a discovery cohort of incident treatment-naïve pediatric patients and validating findings in an independent inception cohort. The lipidomic signature comprising of only lactosyl ceramide (d18:1/16:0) and phosphatidylcholine (18:0p/22:6) improves the diagnostic prediction compared with high-sensitivity C-reactive protein. Adding high-sensitivity C-reactive protein to the signature does not improve its performance. In patients providing a stool sample, the diagnostic performance of the lipidomic signature and fecal calprotectin, a marker of gastrointestinal inflammation, does not substantially differ. Upon investigation in a third pediatric cohort, the findings of increased lactosyl ceramide (d18:1/16:0) and decreased phosphatidylcholine (18:0p/22:6) absolute concentrations are confirmed. Translation of the lipidomic signature into a scalable diagnostic blood test for pediatric inflammatory bowel disease has the potential to support clinical decision making.
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| 8. |
- Eriksson, Per Erik, et al.
(author)
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Procurement of Railway Infrastructure Projects : A European Benchmarking Study
- 2017
-
In: Civil Engineering Journal. - : C EJ PUBLISHING GROUP. - 2476-3055. ; 3:4, s. 199-213
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Journal article (peer-reviewed)abstract
- This benchmarking study compares how railway investments are procured in five European countries: Sweden, Norway, Germany, the Netherlands, and the UK. In total, 19 procurement managers and project managers were interviewed. This study compares the national rail clients' procurement strategies regarding: delivery system, reward system, contractor selection, and collaboration model. Historically, these clients have used in-house production. The first step towards a gradually increased usage of the market was to outsource the construction activities while keeping the design and development competence in-house. All five countries have mainly used Design-Bid-Build contracts in their initial outsourcing. However, the last few years there is a discernible trend in Sweden, Norway, the Netherlands and the UK towards allocating more design and development responsibilities to contractors (i.e. Design-Build contracts) and increasing the strategic focus on cooperation. The UK and the Netherlands are forerunners in this trend that can be viewed as a third step in the transition towards a market oriented railway sector. Norway and Sweden is in the middle of this transition, whereas Germany has not initiated this change. The transition towards a gradually increased usage of the market has two main dimensions; degree of cooperation and degree of contractor freedom, which differs among the countries. The UK and Sweden focus on increasing both these dimensions, while The Netherlands and Norway mostly focus on increasing the degree of contractor freedom. Germany still limits both dimensions by performing design and development in-house and letting contractors compete for construction work in Design-Bid-Build contracts. Due to historical and cultural reasons, Deutsche Bahn in Germany is very hesitant to engage in collaboration with external suppliers; focusing on competition is considered more appropriate and less controversial.
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| 9. |
- Fölster, Stefan, et al.
(author)
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Climate Policy to Defeat the Green Paradox
- 2010
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In: Ambio. - : Springer Science and Business Media LLC. - 0044-7447 .- 1654-7209. ; 39:3, s. 223-235
-
Journal article (peer-reviewed)abstract
- Carbon dioxide emissions have accelerated since the signing of the Kyoto Protocol. This discouraging development may partly be blamed on accelerating world growth and on lags in policy instruments. However, it also raises serious question concerning whether policies to reduce CO2 emissions are as effective as generally assumed. In recent years, a considerable number of studies have identified various feedback mechanisms of climate policies that often erode, and occasionally reinforce, their effectiveness. These studies generally focus on a few feedback mechanisms at a time, without capturing the entire effect. Partial accounting of policy feedbacks is common in many climate scenarios. The IPCC, for example, only accounts for direct leakage and rebound effects. This article attempts to map the aggregate effects of different types of climate policy feedback mechanisms in a cohesive framework. Controlling feedback effects is essential if the policy measures are to make any difference on a global level. A general conclusion is that aggregate policy feedback mechanisms tend to make current climate policies much less effective than is generally assumed. In fact, various policy measures involve a definite risk of 'backfiring' and actually increasing CO2 emissions. This risk is particularly pronounced once effects of climate policies on the pace of innovation in climate technology are considered. To stand any chance of controlling carbon emissions, it is imperative that feedback mechanisms are integrated into emission scenarios, targets for emission reduction and implementation of climate policy. In many cases, this will reduce the scope for subsidies to renewable energy sources, but increase the scope for other measures such as schemes to return carbon dioxide to the ground and to mitigate emissions of greenhouse gases from wetlands and oceans. A framework that incorporates policy feedback effects necessitates rethinking the design of the national and regional emission targets. This leads us to a new way of formulating emission targets that include feedback effects, the global impact target. Once the full climate policy feedback mechanisms are accounted for, there are probably only three main routes in climate policy that stand a chance of mitigating global warming: (a) returning carbon to the ground, (b) technological leaps in zero-emission energy technology that make it profitable to leave much carbon in the ground even in Annex II countries and (c) international agreements that make it more profitable to leave carbon in the ground or in forests.
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| 10. |
- Gustafsson, Cecilia, 1988-, et al.
(author)
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Den svenska marknaden för godstransporter på järnväg : En analys av dominerande ställning
- 2019
-
Reports (other academic/artistic)abstract
- Den svenska godsmarknaden på järnväg avreglerades år 1996. SJ avknoppade godsverksamheten 2001, till det separata men fortfarande statligt ägda företaget Green Cargo. Även om det sedan 1996 har etablerats nya företag är Green Cargo den största aktören på marknaden för godstransporter på järnväg. Konkurrensen har succesivt stärkts och Green Cargo har gått från monopolställning till en genomsnittlig marknadsandel på 55 procent för de svenska godstransporterna på järnväg. Bedömning av huruvida utnyttjande av dominerande ställning förekommer, består av tre kronologiska steg. Inledningsvis (1) definieras den relevanta marknaden, för att sedan kunna (2) beräkna företagets marknadsandel och huruvida de har en dominerande ställning samt (3) bedöma huruvida den dominerade aktören utnyttjat sin position otillbörligt. Föreliggande rapport syftar till att genomföra de två första stegen gällande godstransportmarknaden. Den övergripande frågan är huruvida godstransporter på järnväg ska betraktas som en gemensam marknad. Analysen genomförs i två delar. Den första är en traditionell konkurrensanalys som drivs av konkurrenslagstiftningen (SFS 2008:579) medan den andra avgränsar sig till enbart järnvägstransporter vilket motiveras utifrån EU-direktivet SERA (Single European Railway Area) och järnvägslagen (SFS 2004:519). Den traditionella konkurrensanalysen börjar med att definiera relevanta marknader enligt konkurrenslagen och existensen av dominerade aktörer på dessa marknader undersöks. Den andra analysen utgår från järnvägslagen och inkluderar endast godstransporter på järnväg. Dominansfrågan bedöms i denna andra del genom att beräkna marknadsandelar för de givna marknaderna systemtåg, vagnslast, kombitransporter (kombi) och malmtransporter på Malmbanan. I den andra delen av studien, som utgår från järnvägslagen, är marknaderna givna som systemtåg, vagnslast, kombitransporter och malmtransporter på Malmbanan. Givet dessa marknader beräknas marknadsandelarna för Green Cargo med hjälp av tillgängliga data och antaganden. Studien påvisar att den svenska godsmarknaden på järnväg inte bör ses som en enhetlig marknad. I den traditionella konkurrensanalysen definieras tre relevanta marknader. Green Cargo bedöms vara dominerade på tunga godstransporter i omfattande volymer till eller från industrier i det svenska inlandet där konkurrens från andra trafikslag saknas. På marknaden för medeltunga godstransporter inom Sverige är inte Green Cargo dominerande, då det förekommer konkurrens från andra trafikslag. Avgränsas marknaderna till att bara inkludera järnvägstransporter är Green Cargo dominerade på två av fyra marknader; systemtåg och vagnslasttransporter. En dominerade ställning är dock inte det samma som att konkurrensen inte fungerar.
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| 11. |
- Lagging, Martin, 1965, et al.
(author)
-
Reply.
- 2014
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In: Hepatology (Baltimore, Md.). - : Ovid Technologies (Wolters Kluwer Health). - 1527-3350 .- 0270-9139. ; 60:6, s. 2130-1
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Journal article (other academic/artistic)
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| 12. |
- Lind, Hans, 1950-, et al.
(author)
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The Explanation of Incomplete Contracts in Mainstream Contract Theory : A Critique of the Distinction between "Observable" and "Verifiable"
- 2011
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In: Evolutionary and Institutional Economics Review. - 1349-4961. ; 7:2, s. 279-293
-
Journal article (peer-reviewed)abstract
- Mainstream contract theory often makes a distinction between things that are observable by the contracting parties but not verifiable by a third party. This distinction has, e.g. been used to explain why contracts are incomplete in some dimensions and claimed to provide the foundations of incomplete contract theory.This article sets out to scrutinize the assumption and argues that if something is observable by the parties, the parties can ex ante, without prohibitive costs, make these features verifiable by a third party. This implies that the distinction between observable and verifiable cannot be a fundamental explanation for incomplete contracts. Ex post it can be difficult to verify statements by a third party, but then it must be explained why the parties had not ex ante taken measures to make it possible to verify ex post. A number of such explanations are discussed in the paper. The arguments put forward are based on two detailed examples and also supported by important theories from the philosophy of language, which underline that concepts must be related to something observable in order to be learnt.
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| 13. |
- Mandell, Svante, et al.
(author)
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Too much balance in unbalanced bidding
- 2013
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In: Studies in Microeconomics. - : Sage Publications. - 2321-0222 .- 2321-8398. ; 1:1, s. 23-35
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Journal article (peer-reviewed)abstract
- This article adds to the theoretical base of unbalanced bidding in auction theory. The importance of this concept is justified by being a decisive feature in the make-or-buy decision of a client who cannot rely on repeated interaction, often the case in public procurement, for example. Earlier theoretical models on unbalanced bidding often predict corner solutions, that is, zero bids for unit prices of expected overestimated quantities. However, anecdotal evidence indicates a lack of zero bids in the actual contracts. The article offers a possible explanation for this anomaly by focusing on the risk-aversion of the contractor. Using a simple model, it shows that a contractor with superior information may exploit this in the bidding process to increase her expected revenue. This increases risk exposure. A risk-averse contractor will typically avoid a corner solution to reach an optimal balance between risk and expected return.
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| 14. |
- Manousou, Sofia, 1979, et al.
(author)
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Role of iodine-containing multivitamins during pregnancy for children's brain function: protocol of an ongoing randomised controlled trial: the SWIDDICH study.
- 2018
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In: BMJ open. - : BMJ Publishing Group Ltd. - 2044-6055. ; 8:4
-
Journal article (peer-reviewed)abstract
- Iodine is essential for normal brain development. Moderate and severe fetal iodine deficiency results in substantial to serious developmental delay in children. Mild iodine deficiency in pregnancy is associated with neurodevelopmental deficits in the offspring, but evidence from randomised trials is lacking. The aim of the Swedish Iodine in Pregnancy and Development in Children study is to determine the effect of daily supplementation with 150µg iodine during pregnancy on the offspring's neuropsychological development up to 14 years of age.Thyroid healthy pregnant women (n=1275: age range 18-40 years) at ≤12 weeks gestation will be randomly assigned to receive multivitamin supplements containing 150µg iodine or non-iodine-containing multivitamin daily throughout pregnancy. As a primary outcome, IQ will be measured in the offspring at 7 years (Wechsler Intelligence Scale for Children-V). As secondary outcomes, IQ will be measured at 3.5 and 14 years, psychomotor development at 18 months and 7 years, and behaviour at 3.5, 7 and 14 years. Iodine status (urinary iodine concentration) will be measured during pregnancy and in the offspring at 3.5, 7 and 14 years. Thyroid function (thyroid hormones, thyroglobulin), and deiodinase type 2 polymorphisms will be measured during pregnancy and in the offspring at 7 and 14 years. Structural MRI or other relevant structural or functional brain imaging procedures will be performed in a subgroup of children at 7 and 14 years. Background and socioeconomic information will be collected at all follow-up times.This study is approved by the Ethics Committee in Göteborg, Sweden (Diary numbers: 431-12 approved 18 June 2012 (pregnancy part) and 1089-16 approved 8 February 2017 (children follow-up)). According to Swedish regulations, dietary supplements are governed by the National Food Agency and not by the Medical Product Agency. Therefore, there is no requirement for a monitoring committee and the National Food Agency does not perform any audits of trial conduct. The trial will be conducted in accordance with the Declaration of Helsinki. The participating sites will be contacted regarding important protocol changes, both orally and in writing, and the trial registry database will be updated accordingly. Study results will be presented at relevant conferences, and submitted to peer-reviewed journals with open access in the fields of endocrinology, paediatrics and nutrition. After the appropriate embargo period, the results will be communicated to participants, healthcare professionals at the maternal healthcare centres, the public and other relevant groups, such as the national guideline group for thyroid and pregnancy and the National Food Agency.NCT02378246; Pre-results.
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| 15. |
- Nilsson, Jan-Eric, 1952-, et al.
(author)
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Erfarenheter av privat finansiering av offentlig infrastruktur
- 2017
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Reports (other academic/artistic)abstract
- Utredningen om finansiering av offentliga infrastrukturinvesteringar via skatter, avgifter och privat kapital (dir. 2016:59) gav i oktober 2015 VTI i uppdrag att redogöra för svenska och internationella erfarenheter av privat finansiering av statlig transportinfrastruktur. Denna rapport baseras på en litteraturgenomgång med fokus på de senaste 10 åren. Genomgången bekräftar och underbygger ytterligare de observationer som tidigare gjorts om ämnet: OPS-projekt färdigställs mera ofta inom den ursprungliga tidsramen och kostnadsöverskridanden är mindre vanliga. Däremot finns inga exempel på projektuppföljningar som ger en samlad bild av för- och nackdelar med sådana projekt.
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| 16. |
- Nilsson, Jan-Eric, 1952-, et al.
(author)
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Framtidens beskattning av vägtransporter
- 2020
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Reports (other academic/artistic)abstract
- Statens intäkter från beskattning av vägtrafik kommer att minska i takt med den påbörjade utfasningen av fossila drivmedel. Rapportens syfte är att belysa konsekvenserna av denna omställning med utgångspunkt från två generella principer för beskattning; skatter som syftar till att bekosta offentlig verksamhet respektive skatter som tas ut för att minska mängden externa effekter. En huvudslutsats är att också de fordon som inte använder fossila drivmedel bör beskattas för att minska mängden externa effekter. De viktigaste sådana konsekvenser av den framtida trafiken består av den tunga trafikens slitage på vägarna liksom den trängsel som en stadigt växande trafik kan komma att förorsaka även utanför Stockholm och Göteborg. Dessa skatter kommer att generera intäkter till statskassan, men mycket talar för att de samlade skatteintäkterna från vägtrafiken kommer att minska jämfört med idag. Ett ytterligare resultat av analysen är att staten inte bör ta ut högre skatt än vad som ges av fordonens marginalkostnader. Om så skulle ske kommer kostnaden för fossilfria fordon att öka och övergången till nya teknologier att bromsas.
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| 17. |
- Nilsson, Jan-Eric, 1952-, et al.
(author)
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Kostnadsanalyser av upphandlade kontrakt : två studier av investerings- och reinvesteringsprojekt
- 2018
-
Reports (other academic/artistic)abstract
- I Trafikverkets uppdrag ingår att löpande förbättra verksamhetens produktivitet. Rapportens huvudsyfte är att lägga grund för att följa upp och vidareutveckla den verksamhet som genomförs. För detta ändamål redovisas resultaten av två studier. Den ena jämför kostnader i kontrakt med fakturerad slutkostnad medan den andra analyserar kostnaderna för upphandlade underhållsbeläggningar.Avslutningsvis identifieras ett antal minimikrav som måste ställas på den information som krävs för att genomföra systematiska uppföljningar.
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| 18. |
- Nilsson, Jan-Eric, 1952-, et al.
(author)
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Mapping railways maintenance contracts : the case of Netherlands, Finland and UK
- 2014
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Reports (other academic/artistic)abstract
- In 1988, Sweden was the first country in Europe to separate the ownership of railway infrastructure from traffic operations. Starting in 2002, maintenance has gradually been contracted out. Sweden, Finland and Holland – and previously England – have been in the European forefront regarding the use of competitive tendering of railway maintenance. The description of the situation in the countries indicate important similarities. All clients are trying to attract more contractors to place bids. At the same time, and very outspoken in Finland, the profitability on the market for rail maintenance is not high, making it different to attract new companies to enter the market. Another common aspect concerns the allocation of risk between the parties, indicating different emphasis on fixed price and unit price contracts. A related dimension is the tradeoff between tendering input or output.
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| 19. |
- Nilsson, Jan-Eric, 1952-, et al.
(author)
-
Using a self-selection mechanism for tendering in the construction industry : a case study of railway renewal contracts
- 2023
-
Reports (peer-reviewed)abstract
- One of the consequences of the institutional separation of railway infrastructure from train operations in Europe is a misalignment of incentives in which the actions of one party may create costs for the other. To internalise otherwise external costs of track-works experienced by train operators and customers, it is essential to reform the way in which project contracts are tendered. This study suggests a self-selection mechanism for tendering rail infrastructure activities. Bidders may therefore submit bids based on the industry’s standard Unit Price Contract or a Fixed-Price Contract. The mechanism is designed to increase the possibility for a welfare maximising trade-off between construction and user costs. Using standard Benefit-Cost principles and parameter values, a case study where five switches are replaced provides substance to the discussion. The study provides a starting point for addressing risk in the construction industry and a blueprint for further development by professionals to fill in gaps and to test the approach under a controlled format before full-scale implementation.
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| 20. |
- Nilsson, Jan-Eric, 1952-, et al.
(author)
-
Vikten av att följa upp kommunal upphandling av beläggningsunderhåll
- 2021
-
Reports (other academic/artistic)abstract
- För att fördjupa förståelsen av kommunala upphandlingar av beläggningsarbeten har information om den verksamhet som genomförts 2018 och 2019 samlats in från ett antal kommuner. Svarsfrekvens och tillgång till det underlag som efterfrågats är inte tillräcklig för att dra säkra slutsatser. Ett resultat av insamlingsarbetet är därför att det fortfarande saknas sammanhållen kunskap om kommunernas upphandlingar av beläggningsarbeten. Trots detta är det möjligt att, med utgångspunkt från ett antal observationer som görs, ge preliminära rekommendationer för att långsiktigt stärka verksamheten. Förslagen baseras delvis på det arbete som forskargruppen genomfört under flera års arbete med att analysera Trafikverkets beläggningsarbeten. Medan Trafikverket upphandlar många var för sig stora beläggningsprojekt upphandlar kommunerna ramavtal som specificerar ett antal jämförelsevis små åtgärder som kan komma att avropas under en flerårig avtalsperiod. Trafikverkets beställningar anger därför vad som, inom ett osäkerhetsintervall, ska utföras medan kommunerna beskriver ett antal aktiviteter som kan komma att avropas. Utöver den osäkerhet om vilka arbeten en kommun faktiskt kommer att beställa finns också kunskaps-skillnader mellan den beställande kommunen och de företag som lämnar anbud. Medan var och en av Sveriges 290 kommuner genomför en upphandling med några års mellanrum, lämnar några dominerande entreprenadföretag varje år anbud på flera tiotals upphandlingar i olika delar av landet. Detta gör att budgivarna i många fall har en bättre förståelse av vilken verksamhet som kan komma att avropas än beställaren själv har. Särskilt god förståelse av situationen i en kommun har det företag som innehar det avtal som ska upphandlas på nytt.
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| 21. |
- Nyström, Johan, 1979-
(author)
-
A quasi-experimental evaluation of partnering
- 2008
-
In: Construction Management and Economics. - : Taylor & Francis. - 0144-6193 .- 1466-433X. ; 26:5, s. 531-541
-
Journal article (peer-reviewed)abstract
- Construction managerial literature often argues that there are gains to be made by using partnering. Voices have however been raised to approach partnering in a more neutral perspective and with well-founded methods of evaluation. This study can be seen as an outcome of the criticisms against earlier empirical evaluations by setting out to provide more tangible data and an improved method for evaluating partnering. A quasi-experimental method has been adopted in order to control for other affecting variables and find the unique effect of partnering. This approach strives to match partnering projects with identical non-partnering projects on every relevant variable except partnering. Six hundred and twenty three site meeting minutes from 20 publicly procured projects have been analysed to extract differences between partnering and non-partnering projects concerning cost and quality. Time delays, the amount of disputes, financial outcome and contract flexibility have been used as indicators. The paper has made a first attempt in trying to push the frontier for partnering evaluations forward by providing a new type of data (site meeting minutes) and applying a well-reputed evaluation method (quasi-experiment). The main result is that no systematic or general trends can be seen in the material. This result casts a shadow over the optimistic results from earlier evaluations and suggests that the main contribution of partnering might lie in its intangible effects.
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| 22. |
- Nyström, Johan, 1979-
(author)
-
Barriers for Innovation in Road Construction : A Technical Consultant's Perspective
- 2019
-
In: IOP Conference Series. - : Institute of Physics Publishing.
-
Conference paper (peer-reviewed)abstract
- Technical consultants develop visions into buildable designs. Despite having a large impact on a construction project, there is a lack of research into the consultant's potential contribution to innovations. The main measure to stimulate innovation in the construction sector is providing contractor with degrees of freedom through design-build contracting. This contracting form is not new, but there are still problems with the sector productivity. Consultants enter construction projects in the planning stage and set the framework for what the contactors, in the following phase, can build. This paper aims at identifying the consultants' incentives for innovations in road construction. Four barriers for consultants to preserve degrees of freedom in the planning process have been identified: the legislation, strive for concretion, fixed prices payment schemes and monetary bonuses on finishing the road plan obstruct innovation. Removing such barriers can both improve productivity and contribute to a more sustainable construction market.
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| 23. |
- Nyström, Johan, 1979-, et al.
(author)
-
Beyond terminology : which contracting features promote innovation
- 2014
-
In: Proceedings of the International Conference on Construction in a Changing World, in Kandalana, Sri Lanka. - 9781907842542
-
Conference paper (peer-reviewed)abstract
- Two opposing contracting forms in construction are DB (Design and build) and DBB (Design - bid - build). The first one provides the contractor degrees of freedom in design, which enables innovation. DBB is the safe and traditional contracting form, where the client is responsible for the design and the contractor build accordingly. There is a lack of empirical studies comparing these contracting forms on efficiency and innovation. A first step in comparing is to define and separate the contracts.The straightforward solution is to use the client instigated definitions at face value i.e. a contract is a DB or a DBB according to the client. This is shown to be problematic by using five road construction projects from Sweden. One of the DBB indicates more degrees of freedom in design than a DB contract and only one DB project invites new methods for construction. The paper concludes that contract labelling is not a good proxy for degrees of freedomin design, which is was theoretically drives innovation. This insight facilitates future studies to evaluate contracting forms.
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| 24. |
- Nyström, Johan, 1979-, et al.
(author)
-
Degrees of freedom and innovations in construction contracts
- 2016
-
In: Transport Policy. - : Elsevier BV. - 0967-070X .- 1879-310X. ; 47, s. 119-126
-
Journal article (peer-reviewed)abstract
- DB (Design and build) and DBB (Design-bid-build) represent two different contracting forms in construction. The first provides the contractor degrees of freedom in design, which enables innovation. DBB is the safe and traditional contracting form, where the client is responsible for the design and the contractor builds accordingly. Using a case study approach of five Swedish road construction projects, the present paper compares these contracting forms in terms of innovation. In this, the client's labelling of a contract being DB or DBB is taken at face value. It is established that the actual degrees of freedom for the contractors are highly restricted and that no important difference can be seen between the contracting forms regarding innovation. This implies that it is no reason to expect more innovation simply by labelling contracts as DB. Rational explanations for the usage of DB-contracts with bounds on the degrees of freedom are also suggested. Policy implications for promoting innovation in infrastructure contracting finalise the study. (C) 2016 Elsevier Ltd. All rights reserved.
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| 25. |
- Nyström, Johan, 1979-, et al.
(author)
-
Degrees of freedom in road construction
- 2014
-
Reports (other academic/artistic)abstract
- One policy that is believed to increase the rate of innovation and the level of productivity is to move from Design-bid-build contracts (DBB) to Design-Build contracts (DB). A common view is that the latter provides the contractor more degrees of freedom to enable innovation. This hypothesis consists of two steps, first that DB actually has more degrees of freedom and secondly that more degrees of freedom leads to more innovation. This paper focuses on the first step and is based on a review of five road construction projects – two labelled DBB and three DB. It is demonstrated that there is a gap between the textbook definition of the two types of contracts and the actual design of the examples. The degrees of freedom for the contractor are restricted in both DB and DBB contracting and no significant difference in this dimension could be established. Based on this lack of difference in the five projects, the expectation of innovation for the labelled contracts cannot be settled. Some possible rational reasons for the client to restrict the degrees of freedom are also suggested.
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| 26. |
- Nyström, Johan, 1979-, et al.
(author)
-
Delay Fees in the Procurement of Construction Projects
- 2019
-
In: Journal of Transport Economics and Policy. - : University of Bath. - 0022-5258 .- 1754-5951. ; 53, s. 348-363
-
Journal article (peer-reviewed)abstract
- This paper suggests Delay Fees (DF) to handle temporary congestion during road works. The DF is paid by the contractor based on road users' loss of travel time due to construction. This decentralises the trade-off between construction costs and user time to the contractor, increasing social welfare. The contractor not only will account for user time during each single project, but also is incentivised to develop innovative construction techniques. Compared to other means in the literature for reducing temporary construction, the DF is more general in its focus on user time rather than lane closure.
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| 27. |
- Nyström, Johan, 1979-
(author)
-
Den svenska fordonsbesiktningen : regleringens existensberättigande och välfärdseffekter av reformen
- 2014
-
In: Ekonomisk Debatt. - : Nationalekonomiska föreningen. - 0345-2646. ; 42:5, s. 59-69
-
Journal article (other academic/artistic)abstract
- Den 1 juni 2010 reformerades marknaden för fordonsbesiktningen genom att privata företag tilläts erbjuda dessa tjänster. Tre år efter reformen kan det konstateras att inte mycket har förändrats på marknaden, att det saknas en strukturerad uppföljning av reformens välfärdseffekter samt att förarbetena till reformen inte utredde den grundläggande frågan om fordonsbesiktningens existensberättigande. Föreliggande studie avser att granska reformen utifrån två perspektiv, dels välfärdsteoretiskt, dels hur den obligatoriska fordonsbesikt-ningen motiveras. Välfärdsförluster av reformen är svåra att finna. Därutöver dras slutsatsen att fordonsförordningen som reglerar fordonsbesiktningen även täcks av annan lagstiftning.
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| 28. |
- Nyström, Johan, 1979-
(author)
-
Det reala behovet av infrastruktur : En granskning av empirin och vägen framåt
- 2013
-
In: Investeringar in blanco. - Stockholm : Finansdepartementet. - 9789138239667 ; , s. 51-64
-
Book chapter (other academic/artistic)abstract
- Föreliggande studie syftar till att granska argumenten som lyfts fram för mer svensk infrastruktur. Begreppet infrastruktur avser här statligt finansierad järnväg och väg. Först diskuteras principiella argument som kan användas för att motivera höjda anslag infrastrukturinvesteringar. Därefter granskas rapporter utgivna under de senaste åren. Slutsatsen är att de empiriska underlag som finns för denna debatt är svaga. Därefter diskuteras vad som kan göras för att förbättra detta.
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| 29. |
- Nyström, Johan, 1979-, et al.
(author)
-
Empirical analysis of unbalanced bidding on Swedish roads
- 2019
-
Reports (other academic/artistic)abstract
- Based on anecdotal evidence, claims are made that unbalanced bidding is a major problem in the construction industry. This concept refers to a sealed price auction setting with asymmetric information and unit prices, where information rents are extracted. Theoretical literature has shown that it is rational for an informed contractor to skew unit prices. However, empirical studies on the magnitude of the problem are lacking. As the first quantitative study based on European data, it is shown that unbalanced bidding exists, but in small magnitudes. The result is in line with earlier studies from the US.
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| 30. |
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| 31. |
- Nyström, Johan, 1979-
(author)
-
How to Buy Transport Infrastructure
- 2021. - 1
-
In: International Encyclopedia of Transportation. - : Elsevier. - 9780081026724 - 9780081026717 ; , s. 302-307
-
Book chapter (other academic/artistic)abstract
- Transport infrastructure is most often provided by a public entity, that is, a federal state and/or regional bodies. The public sector has a choice of constructing and maintaining the infrastructure by publicly employed people or by using the market and procuring the product. Many countries seem to choose the latter and contract out this work, which entails the issue of public procurement and contract design. This paper presents the three types of contracts to procure transport infrastructure. The pros and cons of design-bid-build (DBB), design-build (DB), and public–private partnerships (PPP) are described. DBB is the traditional and still most commonly used way of tendering, DB gives the contractor incentives to innovate, while PPP improves the possibility to optimize life cycle cost perspective
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| 32. |
- Nyström, Johan, 1979-
(author)
-
Partnering : definition, theory and evaluation
- 2007
-
Doctoral thesis (other academic/artistic)abstract
- The concept of partnering in the construction industry stands for a collaborative way of working. Examples of partnering projects can be found on every continent. As suggested in the title this thesis makes contributions to three areas of partnering research: the definition of partnering, the theory behind partnering and how to evaluate the effects of the concept. The thesis consists of six papers with the following main results. A new definition of the concept is provided with the partnering flower in the first paper. This definition model is a concrete, flexible and structured way to define partnering. It forces people to concretise and pinpoint which components they include in partnering in a specific setting. The second paper uses contract theory to understand how partnering can be justified from an efficiency perspective. Partnering can either be seen as something that neutralises opportunism when there is an incomplete contract or something that reduces transaction costs for renegotiation of complete contracts when new information arises. Paper 3 is an empirical study of attitudes towards partnering in the Swedish construction industry, which complements the preceding studies. Among the results can be mentioned that support for the definition of partnering presented in paper 1 is found and that most respondents do not see partnering just as a new fad - a result that is consistent from 2004 to 2006. With the theory and the definition settled, it remains to evaluate the effects of partnering. This is done in two steps. The first step (in paper 4) is through reviewing earlier evaluations and providing suggestions on how the assessments can be improved. One of these suggestions is applied in paper 5, with a quasi-experimental evaluation of partnering comparing ten partnering projects to ten similar non-partnering projects. With improved data, mainly based on site meeting minutes, and a more well-founded method, no support can be found for the strong positive outcome of partnering reported in earlier evaluations. The final paper makes a contribution to economic contract theory by questioning one of the essential assumptions in this literature, the distinction between observable and verifiable characteristics. This aspect surfaced during the study of partnering contracts and contract theory.
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| 33. |
- Nyström, Johan, 1979-, et al.
(author)
-
Skew to win, not to profit : unbalanced bidding among informed bidders
- 2019
-
In: Journal of Public Procurement. - : Emerald Group Publishing Ltd.. - 1535-0118 .- 2150-6930. ; 19:1, s. 46-54
-
Journal article (peer-reviewed)abstract
- Purpose: Several sectors, especially the construction industry, use unit price contracting (UPC). This contracting form provides agents, ex ante, with estimated quantities of the work to be done. Competing agents then offer corresponding unit prices i.e. the bid is a price vectors, and most often the lowest vector sum is awarded the contract. This way of procuring is not only transparent but also entails a potential problem of unbalanced bidding. Unbalanced bidding occurs when an informed agent skews unit prices to win the ex ante bid. The concept is not new topic in research, but theoretical models from an economics perspective are not extensive.Design/methodology/approach: This paper will focus on how competition among informed bidders will affect the optimal solution.Findings: It is shown that skewing is still a dominating strategy under competition. However, competition will decrease, but not necessarily eliminate, information rents.Originality/value: In this setting, unbalanced bidding could mainly be seen as a way to win the contract and not to extract information rents. Thus, it would not constitute an efficiency problem for the client.
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| 34. |
- Nyström, Johan, 1979-, et al.
(author)
-
Stimulera konkurrensen i anläggningssektorn : hur behandlas små och medelstora företag i våra grannländer?
- 2016
-
Reports (other academic/artistic)abstract
- Konkurrensen i den svenska anläggningssektorn beskrivs ofta som bristfällig. Därefter uttrycks inte sällan att andra länder har en mer dynamisk marknad med fungerade konkurrens och att Sverige borde dra lärdom. Där slutar ofta analysen. Data som stödjer dessa uttalanden och exempel på hur marknaderna fungerar lyser med sin frånvaro.Föreliggande rapport syftar till att kartlägga konkurrensen på marknaden för vägbyggande i Norge, Danmark, England och Tyskland med kvantitativa data. Det görs genom ett så kallat koncentrationsmått som mäter hur stor den sammanlagda marknadsandelen för de fyra största förtagen är. Resultaten kompletteras med en diskussion om ländernas olika marknadsförutsättningar och initiativ för att stärka konkurrensen. Analysen utgår från en jämförelse med Sverige genom hela rapporten. Fokus ligger på hur möjligheterna för små och medelstora (SME) företag kan förbättra konkurrensen.Det mest framträdande resultatet är att Sverige, i jämförelse med de analyserade länderna, har en hög koncentration på marknaden för vägbyggande. Baserat på jämförbar statistik gällande marknadsandelen för de fyra största företagen som bygger vägar, har Sverige en hög koncentration vars sammansättning av företag inte förändras mellan åren. England har den högsta koncentrationen men till skillnad från Sverige byts de fyra största företagen ut varje år. Utifrån dessa två förhållanden kan konstateras att konkurrensen i Sverige är sämre än jämförda länder.
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| 35. |
- Nyström, Johan, 1979-
(author)
-
The balance of unbalanced bidding
- 2015
-
In: Procedia Economics and Finance. - 2212-5671. ; 21, s. 97-103, s. 97-103
-
Journal article (peer-reviewed)abstract
- Based on anecdotal evidence, claims are made that unbalanced bidding is a serious problem in the construction industry. This concept is based on a situation with a contractor being more informed than the client. The asymmetry in information can be used by the contactor to skew unit prices in the ex ante bid and in order to enhance the ex post profit. This is done by increasing the unit price of a quantity that is expected to go up and lower the unit price of a quantity expected to decrease. Research regarding unbalanced bidding has to a large extent focused on models to assists clients in detecting and contractors in optimising the skew. There is also theoretical literature on efficiency losses of unbalanced bidding. The latter models show that it is rational for an informed contractor to raise unit prices on relative underestimated quantities. However, empirical studies that capture the magnitude of the problem are lacking. This paper sets out to fill that void. The analysis is based on a unique dataset of 15 Swedish road investments and 2 795 observations. Data consist of ex ante unit prices and quantities that are related to the final (ex post) quantities. By looking for a positive correlation between these variables and controlling for other affecting variables, the hypothesis of unbalanced bidding can be empirically tested. Along earlier studies on US data, this paper, using more project specific control variables concluded that the effect is even smaller or non-existent.
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| 36. |
- Nyström, Johan, 1979-
(author)
-
Updating and cleaning out : The “make or buy” decision in construction revisited
- 2019
-
In: 10th Nordic Conference on Construction Economics and Organization. - : Emerald Group Publishing Limited. - 9781838670511 ; , s. 3-8
-
Book chapter (peer-reviewed)abstract
- Purpose - Provide explanations to why firms subcontract. Design/Methodology/Approach - Theoretical analysis based on current and specific conditions of the construction sector and empirical indicators. Findings - Attributes potentially influencing the subcontracting decision are updated. Research Limitations/Implications - The paper will only focus on the make-or-buy decision of the main contractor and not the client. Practical Implications - Contributing to coming analysis on the subcontractor decision. Originality/Value - Updated transaction cost analysis on the construction industry.
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| 37. |
- Olsson, Nils O. E., et al.
(author)
-
Governance regimes for large transport infrastructure investment projects : Comparative analysis of Norway and Sweden
- 2019
-
In: Case Studies on Transport Policy. - : Elsevier. - 2213-624X .- 2213-6258. ; 7:4, s. 837-848
-
Journal article (peer-reviewed)abstract
- The two Nordic countries Norway and Sweden have launched governance regimes for the early phases of transport infrastructure investments after experiencing frequent cost overruns and low cost-benefit ratios. This study seeks to find out if these governance regimes have reduced the escalation of costs from early estimates to finalized projects and influenced the choice of projects away from those with lower benefit to cost ratios. We have compared governance regimes for major transport infrastructure investments in the two countries and examined the development and content of quality assurance activities, the involvement of internal and external parties, their duties and responsibilities, their stage gate models, and how decisions are made. The findings are that both countries have introduced formalizations of their governance regimes that mandate project reviews during the planning process and quality assurance, both of which have increased early cost estimates. One difference was that in Norway, the Ministry of Finance manages the quality assurance scheme and imposes external quality assurance requirements, while Sweden has no corresponding ministerial oversight. Therefore, on the one hand, the process is more strictly formalized in Norway, but on the other hand, cost-benefit ratios appear to have more weight in Sweden. Furthermore, although both countries have done several ex post evaluations, neither country has introduced a formalized ex post evaluation process allowing for systematic examination of the causes of cost overruns and low benefit to cost ratios. Even so, politicians may manoeuvre projects with lower benefit to cost ratios around the governance systems in both countries. Finally, some projects in both countries still have experienced significant cost escalations despite these processes.
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| 38. |
- Olykke, Grith Skovgaard, et al.
(author)
-
Defining abnormally low tenders : A comparison between Sweden and Denmark
- 2017
-
In: Journal of Competition Law and Economics. - : Oxford University Press. - 1744-6414 .- 1744-6422. ; 13:4, s. 666-709
-
Journal article (peer-reviewed)abstract
- The concept of an abnormally low tender is not defined in EU public procurement law. This article takes an interdisciplinary law and economics approach to examine a dataset consisting of Swedish and Danish judgments and verdicts concerning the concept of an abnormally low tender. The purpose is to determine how the concept has developed in practice in two Scandinavian countries with similar legal traditions, and whether the national solutions are economically efficient. The data indicate that economic operators use various pricing strategies which may result in tenders being rejected as abnormally low or the awards of contracts to such tenders being contested. The pricing strategies will (over time) result in the contracting authorities paying too high a price and they are, therefore, economically inefficient. It is concluded that diverse solutions to the handling of abnormally low tenders have developed in the two countries and, notably, that the approaches differ with regard to how they treat different pricing strategies. Thus, the solutions are also different in terms of economic efficiency.
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| 39. |
- Poulikidou, Sofia, 1984, et al.
(author)
-
Impacts on fuel producers and customers of conflicting rules for life cycle assessment
- 2022
-
Reports (other academic/artistic)abstract
- The use of life cycle assessment (LCA) as a tool for estimating the environmental performance of a product or service in a holistic and systematic manner is increasing. Fuel producers may need to apply different methodological frameworks to be used in different contexts; internally for product development activities as well as externally for communication with customers or authorities. Different LCA frameworks may vary in scope, system boundaries (i.e. life cycle stages to be considered) or modelling requirements (such as data demands but also more detailed methodological features). They may also vary in terms of information they can provide in relation to the environmental performance of the product. Those variations could lead to conflicting outcomes and conclusions and may also increase complexity for the LCA practitioner leading to high competence and resource requirements. Within the research project: Impacts on fuel producers and customers of conflicting rules for LCA , the requirements of different LCA frameworks and their implications to fuel producers are investigated. Focus has been given on three specific frameworks that are identified as relevant or potentially relevant for fuel producers, namely: the recast of the EU Renewable Energy Directive (referred to here as RED II), the EU framework for Product Environmental Footprint (PEF), and the framework of Environmental Product Declaration (EPD). The aim of the project is to increase understanding on the different LCA frameworks available and identify whether the multitude of such frameworks gives conflicting recommendations for environmental improvements and fuel choices. The three LCA frameworks listed above were applied in case studies. To illustrate the potential differences that the different frameworks may lead to, a variation of production pathways and feedstocks were selected including first generation as well as advanced biofuels. Based on the results obtained it can be concluded that applying all three frameworks is not a straightforward task. The methods contain fundamental differences and are at different levels of development, maturity, and adoption. In certain situations, they can lead to diverging conclusions as a result of different quantitative outcomes for a specific production pathway, thus influencing decision making processes in different directions. Understanding those differences and underlying assumptions is important for understanding the variations in outcome. The result for a specific fuel could differ substantially depending on the framework applied and the assumptions and interpretations made when applying this framework. Certain methodological parameters were identified to have a greater impact on the results than others: • The three frameworks diverge in the methods applied for modelling waste management, which can be very important for the results when the biofuel is produced from waste. • The frameworks diverge in what approaches are allowed for modelling processes with multiple products. This can be very important for the results when the fuel is co-produced with other products. • The frameworks also diverge in how the electricity supply is modelled. This is not very important for the results in most of our case studies, because the production of these biofuels does not require a lot of electricity. The study confirms that applying a framework like EPD or PEF in addition to RED II would require significant supplementary efforts. Not only because of different rules which were often contradicting or difficult to interpret but also because of additional data and reporting requirements. The need for expertise and resources is increasing for fuel producers to be able to provide EPD and PEF compliant assessments. To enhance the development and harmonization of LCA approaches this project stresses the need for product specific rules (in the form of Product Environmental Category Rules (PEFCR) and Product Category Rules (PCR)) for renewable fuels. Future versions of all three studied frameworks should be clearer on how specific methodological choices are to be applied (e.g., when it comes to allocation and multifunctional processes) as well as when it comes to model electricity supply. RED for example shall be clearer on how to define the electricity region while EPD guidelines on how to define the electricity market. Although it is not realistic to aim for a single unified LCA framework, the biofuel PCR and PEFCR can be developed with RED in mind. Some aspects of the PEF methodology can perhaps also be integrated into RED III that is currently under development. This would enhance the broader adoption of the frameworks among fuel producers. Finally, the involvement and engagement of the industry, and fuel producers themselves is very important. Industry initiatives are essential for the development of biofuel PCR and PEFCR while the general development of the three frameworks can also be influenced. In this study, we also investigated the relationship between the LCA frameworks and schemes for chain of custody certification (CoCC), in particular schemes for mass balance certifications (MBC) to investigate to what extent these schemes complement or overlap with LCA. The purpose of MBC schemes and LCA are different, in the sense that the first aim at verifying the sources and sustainability of total amounts of raw materials used by tracking them throughout the value chain, while the second at quantifying specific environmental impact. The system boundaries are similar, since both cover the entire value chain, but may be applied differently depending on the detailed frameworks applied and choices made in applying the MBC schemes. By identifying and clearly illustrating the variations among the studied frameworks the study enhances application, development, and harmonization of LCA, in a broader perspective, informs LCA practitioners but also decision makers and provides insights on how the identified challenges can be addressed.
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| 40. |
- Pyddoke, Roger, 1956-, et al.
(author)
-
Två studier av kostnader för upphandlade asfaltbeläggningar
- 2014
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Reports (other academic/artistic)abstract
- I detta notat redovisas resultaten av två studier som analyserat kostnader för Trafikverkets vägbeläggningar. Trafikverket har tillhandahållit två olika källor för information om beläggningsåtgärder. Den första är VUH databasen som innehållande mer än 20 000 registrerade och avslutade beläggningsuppdrag mellan åren 2001 till 2011. Den andra informationskällan baseras på en sammanställning som gjorts av 285 avtal om underhållsbeläggningar, det vill säga reinvesteringar i form av ny beläggning på längre vägavsnitt, som upphandlats 2012 och 2013. Den första studien analyserar VUH databasens användbara observationer. Resultaten visar att bitumenpriset har stark inverkan på kostnaden för beläggningar: En ökning av bitumenpriset med 10 procent ökar priset på asfalt med mellan 1,2 och 3,7 procent. Det finns vissa tecken på stordriftsfördelar i verksamheten. Kostnaderna för beläggningen ökar således med mellan 7 och 10 procent när beställningarna (i ton) ökar med 10 procent. Konkurrens mätt som antalet aktiva operatörer i regionen under året har ingen signifikant effekt. Med viss variation har Skåne lägre och region Norr högre kostnader än övriga regioner. Den andra studien visar att kostnaden för en underhållsbeläggning ökar med nästan sex procent om storleken på beställningen ökar med 10 procent. Det finns därmed stordriftsfördelar i att öka storleken i detta avseende. Storleken på ett avtal kan också, som noterades ovan mätas som antal delkontrakt i varje grupp. Analysen pekar på att kostnaden ökar med antalet delkontrakt. Det innebär att även om det kan finnas stordriftsfördelar förenade med att upphandla underhållsbeläggningar som är stora mätt som belagd yta, kan det finnas skäl att inte klumpa samman allt för många delprojekt i ett och samma kontrakt om avståndet mellan de olika delarna är för långt.
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| 41. |
- Rembeck, Karolina, et al.
(author)
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Variants of the inosine triphosphate pyrophosphatase gene are associated with reduced relapse risk following treatment for HCV genotype 2/3.
- 2014
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In: Hepatology (Baltimore, Md.). - : Ovid Technologies (Wolters Kluwer Health). - 1527-3350 .- 0270-9139. ; 59:6, s. 2131-2139
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Journal article (peer-reviewed)abstract
- The present study evaluated the impact of variations in the inosine triphosphate pyrophosphatase (ITPase) gene (ITPA) on treatment outcome in patients with hepatitis C virus (HCV) genotype 2/3 infection receiving peginterferon-α2a and lower, conventional 800 mg daily dose of ribavirin. Previous studies using higher, weight-based ribavirin dosing report that patients carrying polymorphisms encoding reduced predicted ITPase activity show decreased risk of ribavirin-induced anemia but increased risk of thrombocytopenia, with no impact on elimination of virus. Three hundred fifty-four treatment naïve HCV genotype 2/3 infected patients, enrolled in a phase III trial (NORDynamIC), were genotyped for ITPA (rs1127354 and rs7270101). Homo- or heterozygosity at Ars1127354 or Crs7270101, entailing reduced ITPase activity, was observed in 37% of patients and was associated with increased likelihood of achieving sustained virological response (SVR) (P=0.0003 in univariate and multivariate analyses) accompanied by a reduced risk of relapse among treatment-adherent patients. The association between ITPA variants and SVR remained significant when patients were subdivided by the 12- and 24-week treatment duration arms, HCV genotype, fibrosis stage and IL28B genotype, and was not secondary to improved adherence to therapy or less pronounced anemia. Gene variants predicting reduced predicted ITPase activity also were associated with decreased risk of anemia (P<0.0001), increased risk of thrombocytopenia (P=0.007), and lower ribavirin concentrations (P=0.02). Conclusion: These findings demonstrate a novel ribavirin-like association between polymorphisms at ITPA and treatment efficacy in chronic hepatitis C mediated by reduced relapse risk. We hypothesize that patients (63%) being homozygous for both major alleles, leading to normal ITPase activity, may benefit more from the addition of ribavirin to present and future treatment regimens for HCV in spite of concomitant increased risk of anemia.
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| 42. |
- Rostami, Elham, 1979-, et al.
(author)
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Recurrent papillary craniopharyngioma with BRAFV600E mutation treated with neoadjuvant-targeted therapy.
- 2017
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In: Acta Neurochirurgica. - : Springer Science and Business Media LLC. - 0001-6268 .- 0942-0940. ; 159:11, s. 2217-2221
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Journal article (peer-reviewed)abstract
- Craniopharyngiomas are histologically benign but locally aggressive tumors in the sellar region that may cause devastating neurological and endocrine deficits. They tend to recur following surgery with high morbidity; hence, postoperative radiotherapy is recommended following sub-total resection. BRAFV600E mutation is the principal oncogenic driver in the papillary variant of craniopharyngiomas. Recently, a dramatic tumor reduction has been reported in a patient with BRAFV600E mutated, multiply recurrent papillary craniopharyngioma using a combination therapy of BRAF inhibitor dabrafenib and MEK inhibitor trametinib. Here, we report on near-radical reduction of a growing residual BRAFV600E craniopharyngioma using the same neoadjuvant therapy.
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| 43. |
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| 44. |
- Önskog, Thomas, 1979-
(author)
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The Skorohod problem and weak approximation of stochastic differential equations in time-dependent domains
- 2009
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Doctoral thesis (other academic/artistic)abstract
- This thesis consists of a summary and four scientific articles. All four articles consider various aspects of stochastic differential equations and the purpose of the summary is to provide an introduction to this subject and to supply the notions required in order to fully understand the articles. In the first article we conduct a thorough study of the multi-dimensional Skorohod problem in time-dependent domains. In particular we prove the existence of cádlág solutions to the Skorohod problem with oblique reflection in time-independent domains with corners. We use this existence result to construct weak solutions to stochastic differential equations with oblique reflection in time-dependent domains. In the process of obtaining these results we also establish convergence results for sequences of solutions to the Skorohod problem and a number of estimates for solutions, with bounded jumps, to the Skorohod problem. The second article considers the problem of determining the sensitivities of a solution to a second order parabolic partial differential equation with respect to perturbations in the parameters of the equation. We derive an approximate representation of the sensitivities and an estimate of the discretization error arising in the sensitivity approximation. We apply these theoretical results to the problem of determining the sensitivities of the price of European swaptions in a LIBOR market model with respect to perturbations in the volatility structure (the so-called ‘Greeks’). The third article treats stopped diffusions in time-dependent graph domains with low regularity. We compare, numerically, the performance of one adaptive and three non-adaptive numerical methods with respect to order of convergence, efficiency and stability. In particular we investigate if the performance of the algorithms can be improved by a transformation which increases the regularity of the domain but, at the same time, reduces the regularity of the parameters of the diffusion. In the fourth article we use the existence results obtained in Article I to construct a projected Euler scheme for weak approximation of stochastic differential equations with oblique reflection in time-dependent domains. We prove theoretically that the order of convergence of the proposed algorithm is 1/2 and conduct numerical simulations which support this claim.
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