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Phenotypic Characterization of a Novel Human Alzheimer’s Disease Model to Study Microglia
No full textAlzheimer’s disease (AD) is the most prevalent form of dementia and accounts for approximately 60-70% of all dementia cases [1]. The pathological hallmarks of AD include the accumulation of amyloid-β plaques and tau tangles [1]. In addition to these hallmark features, neuroinflammation plays a crucial role in the progression of the disease [2]. Microglial cells, the brain’s resident immune cells, are key players in neuroinflammatory processes [2]. In response to external and internal stimuli, they transform into different states, each characterized by distinct phenotypic changes [2]. Given their central role in mediating neuroinflammation and their sensitivity to disease-related biomarkers, it is expected that AD significantly influences the
microglial phenotype.
In this study, we developed and evaluated a novel human cell model to investigate changes in microglial phagocytic activity, gene expression, and morphology when cultured in cerebrospinal fluid (CSF) derived from AD patients. Human-induced pluripotent stem cell-derived microglia and cortical neurons were seeded into monocultures and cocultures, followed by incubation in CSF from AD and non-AD (CTRL) patients. The cell model was then analyzed using various functional assays, qPCR, and a morphology analysis pipeline for ImageJ and RStudio.
The results showed that CSF exposure had no adverse effects on microglial viability or proliferation, supporting the model’s robustness. While qPCR and phagocytosis assays indicated increased activation in AD-CSF-treated microglia compared to CTRL-CSF, no morphological differences were observed between these groups. Instead, pronounced differences in morphology were detected between the CSF-treated and coculture media (CoM) treated conditions, highlighting the influence of CSF-derived substances on microglial morphology. These results demonstrate that the cell model can be used to study microglial phenotypic changes when cultured in AD-CSF and CTRL-CSF. However, additional analyses are needed to detect morphological differences between microglia exposed to AD- and CTRL-C
Skillnader mellan projekterad och faktisk energianvändning i byggnader: Orsaker och lösningar
No full textBygg- och fastighetssektorn står i dagsläget för en betydande del av Sveriges totala utsläpp
och energianvändning, vilket gör det extra viktigt att arbeta med energioptimering och
energieffektivisering. För att leva upp till de energikrav som ställs krävs att byggnaden i drift
presterar enligt de energiberäkningar som utförts. Trots detta uppstår det ofta skillnader
mellan den projekterade och den faktiska energianvändningen i byggnader. I denna rapport
har detta fenomen har valt att benämnas som energigapet.
Syftet med examensarbetet har varit att undersöka de vanligaste orsakerna till att detta
energigap uppstår med ett särskilt fokus på hur byggprocessen och de installationstekniska
systemen påverkar slutresultatet. Målet med arbetet har varit att ta fram riktlinjer och
arbetssätt som kan användas i framtida byggprojekt för att minska skillnaden mellan beräknad
och verklig energianvändning.
Arbetet har byggt på tre metoder: en litteraturstudie, kvalitativa intervjuer samt en dataanalys
av tre nyproducerade flerbostadshus. Litteraturstudien har analyserat tidigare forskning kring
orsakerna till energigapet samt förbättringsförslag. I intervjustudien har personer från olika
roller i byggbranschen fått dela med sig av sina erfarenheter och insikter kring energigapet,
vilket gett en bred praktisk bild av problemet. Dataanalysen har använts för att konkret
jämföra projekterade värden med den faktisk uppmätta energianvändningen och därmed
illustrera avvikelsens omfattning.
Resultaten visar att orsakerna till energigapet kan delas in i tre huvudkategorier: tekniska
orsaker, processrelaterade orsaker och drift- och beteendemässiga orsaker. Återkommande
faktorer som identifieras är exempelvis brister i energiberäkningar, saknad energisamordning,
sen involvering av driftpersonal och otillräcklig uppföljning. Därefter förs en diskussion där
resultaten vägs samman och där det presenteras framtida förbättringsåtgärder. Arbetet
avslutas med en slutsats där det nämns fyra konkreta rekommendationer till branschen för att
minska energigapet
Exploring the Visibility of Emission Data in Transport Chains Challenges within emissions traceability for companies and their stakeholders
No full textIn response to the increasing urgency of climate change and the introduction of reg-
ulatory frameworks such as the EU’s Corporate Sustainability Reporting Directive
(CSRD), companies are under mounting pressure to quantify and report greenhouse
gas (GHG) emissions throughout their value chains. The transport sector, which ac-
counts for a significant share of global emissions, presents particular challenges due
to its fragmented structure, complex stakeholder networks, and widespread reliance
on subcontracted services. Despite recent standardisation efforts, including ISO
14083 and the GLEC Framework, companies continue to face difficulties in access-
ing high-quality emission data, ensuring methodological consistency, and facilitating
reliable data exchange.
This study explores the barriers and enablers related to the collection and sharing of
transport emissions data between transport service providers and transport buyers.
A qualitative case study was conducted, based on 19 semi-structured interviews with
companies operating across various sectors and supply chain roles. The collected
data was analysed through a thematic analysis, which allowed for the identification of
recurring patterns and underlying challenges across stakeholder groups. To structure
the findings and enhance clarity, a framework was developed that organises the key
themes and illustrates how they interact within the broader context of transport
emissions reporting.
The results of the study show that the main barriers to effective emissions reporting
lie not in the absence of regulatory ambition, but in the limited practical capacity
to meet increasing data demands. A key gap exists between top-down policy re-
quirements and the day-to-day realities of data collection and exchange, especially
within subcontracted and SME-dominated logistics chains. The findings highlight
the urgent need for interoperable digital systems, harmonised templates, and support
mechanisms that enable more efficient, accurate, and scalable reporting. Further-
more, the study underscores the importance of sector-wide collaboration and shared
responsibility among transport buyers, providers, and policymakers
Prompt Engineering with Requirements in GitHub Copilot
No full textPractices within requirements engineering are essential for the success of software projects. In particular, document analysis enables the elicitation of requirements without engaging directly with the stakeholders. This thesis presents a method of scraping documents from English open-source software repositories hosted on GitHub and extracting requirements from these documents. This is done in order to supply GitHub Copilot with more context when prompting it to repay self-admitted technical debt expressed through TODO comments. Three different prompt tem plates were created to evaluate this approach. The first template had no require ments in the prompt, the second template had some relevant requirements, and the third one had all the relevant requirements. After prompting Copilot, prompts from the first template were shown to the best at repaying debt– amounting to a repayment rate of 72%. However, they also accounted for the most repayments that did not conform to all the requirements. While prompts from the third template showed the best results in regard to this, they displayed a lower debt repayment rate of 64%. Finally, it is noted that self-admitted debt is not truly repaid unless done in a way that conforms to the relevant requirements. As such, there is a need for future research to expand upon this particular problem through the development of a robust framework
Kontaktlös andningsmonitorering med Radio Frequency Identification (RFID)
No full textI detta kandidatarbete undersöks möjligheten att använda RFID-teknologi för kontaktlös
monitorering av andningsrörelser. Genom att analysera fasskiftningar i radiosignaler
reflekterade från passiva RFID-taggar placerade på bröstkorgen och buken
så har systemets förmåga att detektera andningsmönster utvärderats. Mätningar
genomfördes både på en simuleringsdocka och en mänsklig försöksperson, med varierande
andningsfrekvenser och antal taggar. Den insamlade data analyserades med
hjälp av MATLAB i både tids- och frekvensdomän, och resultatet jämfördes med
signaler från ett kommersiellt respirationsband. Resultaten visar att RFID-tekniken
på ett tillförlitligt sätt kan registrera andningsrörelser och identifiera asymmetrier i
andningen, samtidigt som den erbjuder en kontaktlös, kostnadseffektiv och flexibel
lösning jämfört med etablerade metoder. Arbetet identifierar även utmaningar relaterade
till signalstabilitet, taggplacering och tekniska begränsningar, vilket ligger
till grund för förslag på framtida förbättringar
Investigating Degradation Mechanisms in Sodium Solid-State Batteries
No full textSolid-state sodium batteries are promising candidates for next-generation electro chemical energy storage, with improved sustainability and safety compared to cur rent lithium-ion technologies. In addition, solid electrolytes could potentially en able the use of sodium metal anodes for increased energy density. However, these
electrodes currently have short lifetime due to electro-chemo-mechanically coupled
degradation mechanisms, which must be well understood in order to mitigate the
problems and extend the lifetime of solid-state sodium batteries. This thesis investi gates a sulfide solid electrolyte, with a particular focus on processes at the interface
with sodium metal. The study involves electrochemical characterization techniques
and imaging with X-ray tomographic microscopy, in order to gain insights into the
processes that limit cell lifetime and efficiency. The results show rapid polarization
of the cells, attributed to chemical degradation at the interface between sodium
metal and the electrolyte. The resulting interphase layer fails to passivate the elec trode, leading to capacity loss from the irreversible side reactions that continuously
consume sodium metal and solid electrolyte. The use of chlorine-doped electrolytes
and protective interlayers presents promising strategies to improve the interfacial
stability and extend the lifetime of sodium metal electrodes
Naturbaserade lösningar för att återställa jordbruksmark i ett krigsdrabbat Ukraina
No full textUkrainas jordbruksmark är känd för sina svarta, bördiga jordar som länge varit en stor tillgång samt
gjort landet till en ledande exportör av spannmål till både EU och resten av världen. Denna jord har
skadats allvarligt av kriget, med bland annat föroreningar och markkompaktering, vilket hotar landets
livsmedelsförsörjning och ekonomi. Traditionella saneringsmetoder är ofta kostsamma och långsamma,
vilket ökar behovet av naturbaserade lösningar för en effektiv återställning. Denna litteraturstudie
inventerar vanliga föroreningar efter krig samt undersöker tre naturbaserade saneringsmetoder:
fytoexkludering, jordtillsatser och biosorption. Syftet med studien är att undersöka dessa metoder för att
sanera krigsförorenad jordbruksmark i Ukraina. Studien för de naturbaserade lösningarna är baserad på
PRISMA-metoden och använde slutligen 42 vetenskapliga källor. Resultaten presenteras i tabeller
utifrån metodspecifika kriterier. Studien visar att fytoexkluderande grödor som raps, vete och korn
effektivt kan minska upptag av tungmetaller som Cd och Pb, särskilt i kombination med jordtillsatser.
Jordtillsatser, främst biokol, minskar tungmetallers rörlighet och biotillgänglighet i jorden, samt bedöms
vara den mest lovande metoden för återställning av ukrainsk jord. Biosorption visar potential men kräver
ytterligare forskning innan praktisk tillämpning. Slutsatsen är att kombinationen av fytoexkludering och
jordtillsatser är mest lämplig för en effektiv rehabilitering av krigsförorenad jordbruksmark i Ukraina
Passwordless Authentication System Using TKey
No full textThreats targeting authentication systems are becoming more widespread in the current
digital landscape, and passwords are challenged in their role as the dominant
authentication method due to poor user habits and cognitive limitations. This thesis
describes the design and implementation of a passwordless authentication system
developed in Python and Go for a simple web application and proxy server.
A two-factor authentication system was implemented utilizing a TKey (Chalmers
version) from Tillitis AB with Ed25519 signing, as well as Time-based One-Time
Password (TOTP) functionality. Additionally, a recovery mechanism was implemented
that utilizes mnemonic phrases to handle the loss of a TKey. The project
explores the possibilities of passwordless authentication using a TKey, and in the
broader sense hardware-based authentication. It demonstrates that hardware-based
authentication schemes relying on cryptographic signatures are effective candidates
for tomorrow’s authentication systems
Reimagining accessible architecture: Inclusive housing through a pluriversal approach
No full textHow can a pluriversal approach to the transformation of existing housing foster accessibility, adaptability, and inclusivity for diverse users?
Contemporary housing often overlooks the varied needs of accessibility, treating it as an afterthought rather than an integral aspect of design. This oversight results in environments that segregate and exclude individuals with disabilities, reinforcing social marginalisation. While investigating accessibility and exclusion in architecture, pluriversal design theory appeared applicable. The theory introduces seven design principles, which in this thesis have been used as the foundation for the process. However, to move from theory to architectural design, it became necessary to develop my own strategies in response to the specific site, context, and people involved.
This thesis investigates how we can create homes that embrace diversity and explores how we can live in a world of multiple worlds, a pluriverse. The author does not believe that architects know best or that they alone should decide what is right for others.
It is the diversity of people that forms a good architectural project. This belief shaped the participatory process at the core of the thesis. Interviews and workshops were conducted with a small group of people with varied needs, backgrounds, and challenges. Their insights informed the design and are represented through five fictional personas. These personas are used to develop narratives that reveal how space is experienced, both before and after transformation.
The speculative design proposal reflects how a pluriversal approach, supported by participation, can shape more inclusive environments. The transformation of an existing housing development in Oslo serves as the test site. The project is not intended to provide universal answers, but to offer a way of working differently, one that values empathy, lived experience, and designing with, not for, others. It also points to the need for further reflection on whether current regulations can support more inclusive and plural ways of designing
