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Senast publicerade

Analyzing the structural conformation andstability of timP RNA using Optical Tweezers
(2026) Sölsnes, Isidor
RNA molecules play a central role in gene regulation, where structural dynamics strongly influence their biological function. In particular, pseudoknot formation has been implicated in regulating translation in bacterial toxin-antitoxin systems, including the timP RNA system. In this work, single-molecule optical tweezers (OT) were used to investigate the force-dependent unfolding behavior of timP RNAconstructs, includingwild-type(WT), and two mutants. RNA molecules were tethered in a dual-trap optical tweezers setup and subjected to controlled mechanical stretching while force-extension trajectories were recorded and analyzed. Two distinct unfolding patterns were frequently observed and classified as low force (LF) and high-force (HF) patterns. The HF pattern, characterized by a pronounced unfolding event at higher forces, was associated with the pseudoknot conformation based on the corresponding unfolding of approximately 100 nucleotides. This amount was consistent with the expected size of the pseudoknot structure. The relative occurrence of these HF patterns in the WT system increased with decreased pulling speed and increased refolding time. Similar trends were observed for the M2 and M2M2’ mutants, although the magnitude of the changes varied between constructs. HF trajectories were further analyzed using scatterplot-based clustering of individual force-drop events to extract statistical properties such as unfolding forces and estimated contour length changes. Three reoccurring groups of unfolding events were identified across the investigated constructs, with estimated nucleotide releases broadly corresponding to the expected sizes of structural elements within the timP RNA. Differences in the force and nucleotide distributions were also observed between WT and mutant constructs. These results indicate that both experimental conditions and sequence modifications influence the force-dependent unfolding behavior of timP RNA, while the observed unfolding patters and contour length changes support the association of the high-force pattern with the pseudoknot-containing conformation.
An Integrated Decision- Support Framework for Optimising Industrial Hall Design - A Case Study of Valmet
(2026) Kanhirathingal, Swathi Mohan
Industrial machine halls are large-volume buildings with demanding spatial, structural, energy, and operational requirements. Decisions made at the early design stage, especially those related to basement configuration, can have a major effect on energy demand, embodied carbon, construction cost, operating cost, safety, and maintenance accessibility. This thesis develops an integrated decision-support framework to help compare industrial hall design alternatives during the early design stage. The framework uses Key Performance Indicators (KPIs) across four performance dimensions: energy, environmental, economic, and operational performance. The framework is applied to a Valmet tissue machine hall case study. Valmet is a global technology company that provides process technologies, automation, and services for the pulp, paper, and energy industries. In this study, three tissue machine hall alternatives are compared: a two-pit solution, an extended basement solution, and a full basement solution. These alternatives are evaluated under Swedish and Spanish climate scenarios. The energy assessment considers heating demand and ventilation fan electricity, while the environmental assessment focuses on embodied carbon from structural materials. The economic assessment includes CAPEX and OPEX, and the operational assessment evaluates safety and maintenance accessibility using structured scoring. The results show that no single alternative performs best in all dimensions. The two-pit solution has the lowest energy use, embodied carbon, and operating cost, but scores lowest in operational performance. The full basement solution performs best in terms of safety and maintenance accessibility, but has the highest material use, embodied carbon, construction cost, and energy demand. The extended basement solution provides the most balanced performance overall. The study shows that a KPI-based framework can support clearer and more systematic early-stage decision-making by making trade-offs between different performance dimensions visible.
BIM Derived Quantity Checks for Takt Planning Control in Interior Works: Identifying Capacity Sensitive Work Packages Through a BIM to Excel to Revit Workflow
(2026) Rijil, Johny; Ståhl, Theodor
Takt planning in construction organizes trades through defined locations and repeated work packages so that production can follow a planned rhythm. During interior works, that rhythm depends on whether the work assigned to each location can be completed within the available takt time and whether the information behind the plan remains sufficiently stable. Design changes can alter the quantity of work assigned to a zone, while planning assumptions such as productivity determine how that quantity is translated into time. This thesis examines how BIM-based quantity information can support takt planning control and revision support in interior works by making this relationship visible at the level where production is planned. The research is framed through design science because it develops and demonstrates a planning-support artifact in response to a practical information problem. Nine semi-structured practitioner interviews provide experience of takt planning and control, while a controlled Revit prototype and an anonymized residential build ing model are used to develop and demonstrate the artifact. The resulting BIM to Excel to Revit workflow extracts model quantities through Revit schedules and converts them into planning information in Excel. Selected plan information is then prepared for writeback to Revit through Dynamo and CSV files. The calculation uses one work package in one zone as the planning unit. Quantity is translated into cycle time through a productivity assumption and compared with the selected takt capacity through overload and loaded ratios. The controlled prototype demonstrated one planning unit that exceeded the complete takt period and another that remained within it while occupying part of the selected load-adjusted capacity. In the project-model application, every planning unit required one takt period under the final crew-based productivity assumptions. Loaded ratios still varied across the work packages, showing differences in the share of the selected load-adjusted capacity occupied by their calculated cycle times. The interviews place a boundary around what this quantity-based check can represent. Practitioners described production problems that arise even when the planned workload appears feasible, such as missing prerequisites and failed handovers. These conditions depend on site control and production knowledge that are outside the quantity calculation. The workflow therefore represents the part of takt reliability that can be examined through modeled work content and the assumptions used to translate that content into takt capacity. The theoretical contribution lies in the operational connection between BIM-derived quantity information and planning-stage takt capacity through the combined planning unit of zone and work package. Existing research provides time-based workload logic for takt planning and separate approaches for structuring BIM information for production. The workflow connects these areas by carrying BIM-derived quantities into zone and work-package capacity calculations under visible assumptions and retaining separate model and plan states for traceability. Its interpretation remains bounded by the available model condition, the selected quantity drivers, manual coding, and productivity assumptions. Repeated real project revisions were outside the empirical test.
När målen krockar; Ekonomiska och miljömässiga avvägningar vid renovering av miljonprogrammet
(2026) Sandahl, Anna; Stoor, Ida
Klimatförändringarna intensifieras samtidigt som bygg– och fastighetssektorn står för en betydande del av Europas energianvändning och klimatpåverkan. För att nå Europeiska unionens mål om klimatneutralitet till år 2050 krävs omfattande energieffektiviseringar av det befintliga byggnadsbeståndet, där miljonprogrammets flerbostadshus utgör en särskilt komplex utmaning till följd av omfattande renoveringsbehov och skärpta krav på energiprestanda (Europaparlamentet och Europeiska unionens råd, 2025). Samtidigt innebär energieffektiviserande åtgärder ofta betydande investeringskostnader och ekonomiska risker, vilket aktualiserar frågor om hur ekonomiska och miljömässiga mål prioriteras och vägs mot varandra i praktiska renoveringsprojekt. Studien syftar till att analysera hur ekonomiska och miljömässiga målsättningar hanteras och prioriteras vid renovering av befintliga flerbostadshus, med särskilt fokus på åtgärder i klimatskalet under projektens tidiga skeden. Arbetet genomförs som en kvalitativ fallstudie av renoveringsprojektet på Mandolingatan 39–43 inom Bostads AB Poseidons fastighetsbestånd och baseras på semistrukturerade intervjuer samt dokumentanalys. För att sätta resultaten i ett bredare sammanhang inkluderas även inslag från nyproduktionsprojektet Kvarteret Omställningen inom samma koncern. Resultaten visar att avvägningar mellan ekonomi och hållbarhet i hög grad formas av hur åtgärders ekonomiska risk, tekniska genomförbarhet och organisatoriska konsekvenser bedöms i projektens tidiga skeden. Investeringar i klimatskalet värderas inte enbart utifrån deras potentiella klimatnytta och energibesparing, utan även utifrån osäkerheter kopplade till kostnader, teknisk status och långsiktig förvaltning. Lösningar som uppfattas som ekonomiskt förutsägbara och tekniskt beprövade tenderar därför att prioriteras framför mer långtgående hållbarhetsåtgärder, särskilt i projekt där osäkerheten kring byggnadens förutsättningar är stor. Studien visar samtidigt att organisatorisk styrning och interna prioriteringar har avgörande betydelse för hur hållbarhetsmål omsätts i praktiken. När hållbarhetsfrågor Integreras tidigt i beslutsprocessen och förankras i organisationens strategiska arbete skapas större förutsättningar att genomföra mer ambitiösa klimatåtgärder. Resultaten indikerar därmed att omställningen mot ett mer hållbart byggande inte enbart är en teknisk eller ekonomisk fråga, utan även en organisatorisk process där arbetssätt, styrverktyg och beslutsstrukturer successivt behöver utvecklas. Studien bidrar med fördjupad kunskap om hur hållbarhetsambitioner hanteras i praktiken vid renovering av miljonprogrammets flerbostadshus. Resultaten belyser särskilt hur möjligheten att genomföra mer långtgående hållbarhetsåtgärder är nära kopplad till organisationers förmåga att integrera långsiktiga klimatmål i projektens ordinarie ekonomiska och strategiska beslutsfattande.
Utredande projektering och produktionsplanering av rambro
(2026) Eriksson-Troje, Matheus; Grueso, Adriano