Due to the large quantities of waste in the construction industry, a circular return packaging system is evaluated as bearers used for gypsum deliveries. The master thesis is written together with the construction company JM AB with the goal of being able to support future strategies for the development of more sustainable packaging solutions. This has been done by a comparative life cycle analysis of the current linear system of wood chips bearers, which is compared with a theoretical circular system of plastic bearers used with a return system. The two different bearers with respective processes are compared, in order to evaluate the environmental impact and further evaluate the conditions when a return system is preferable. By creating two life cycle analyses of both systems in the SimaPro computer software and comparing them with the functional unit, 50 deliveries of 42 discs of gypsum are the two different ways of delivering gypsum compared. The result shows that two returns per plastic bearer are needed to ensure that the seven selected environmental impact categories are lower than using wood chips bearers. In the sensitivity analysis, different scenarios are tested, where one conclusion of the analysis is that the type of energy used for the manufacture of the bearers is very important for the result. The discussion addresses the problem that plastic is not a renewable material, and today's conditions on construction sites result in return packaging being handled as disposables. / På grund av byggbranschens stora mängder avfall utvärderas ett cirkulärt emballagealternativ för underslag som används vid leveranser av gips. Examensarbetet görs tillsammans med byggföretaget JM AB med målet att kunna stödja framtida strategier för utveckling av mer hållbara emballagelösningar. Har gjorts genom en jämförande livscykelanalys av det nuvarande linjära systemet av träspånsunderslag vilket jämförs med ett teoretiskt cirkulärt system av plastunderslag som går igenom ett retursystem. De två olika underslagen med respektive processer ställs mot varandra för att utvärdera miljöpåverkan för att vidare bedöma under vilka förutsättningar ett retursystem är att föredra. Genom att bygga upp två livscykelanalyser av båda systemen i dataprogrammet SimaPro som jämförs genom den funktionella enheten 50 leveranser av 42 skivor gips de två olika sätten att leverera gips. Resultatet visar att det krävs två returer per plastunderslag för att de sju utvalda miljöpåverkanskategorierna ska vara lägre än för träspånsunderslagen. I känslighetsanalysen testas olika scenarion, där slutsatsen av analysen är att typen av energi som används för tillverkningen av underslagen är mycket betydelsefull för resultatet. Diskussionen tar upp problematiken med att plast inte är ett förnyelsebart material och att dagens förutsättningar på byggarbetsplatser leder till att returemballage hanteras som förbrukningsvara.

The construction of cities involves the use of land for new spaces and infrastructure. Construction on undeveloped land poses a dilemma on how to deal with the natural resources found on the construction site. Circular economy could provide guidelines on how to harness these resources, so they become products that circulate through as many cycles as possible, therefore decreasing resource consumption and waste. This research aims to explore alternatives to harness the natural materials extracted during the land clearance process of a new urban district: Sollihøgda plussby. Additionally, a new method to examine the circularity of the suggested products will be tested: the longevity indicator. The method of this thesis consists of three parts: (1) an inventory to define which natural materials are found in the construction site and their main characteristics, (2) interviews with industry experts to gain a technical insight on the possible uses for the materials, and (3) a longevity indicator to measure the circularity of the proposed uses. This research found that the forest in Avtjerna consists of Norway spruce, Scots pine and birch. The sediments are mostly humus with a turf sheet cover, while most of Avtjerna’s bedrock is categorized as rhomb porphyry lava. Norway spruce and rhomb porphyry lava have the required quality to become high-quality products for the construction industry, and they could be used directly in the project. High-quality products have longer lifetimes and more possibilities of recycling and reuse, therefore they scored higher when calculating the longevity indicator, which means a higher material retention. The other materials (Scots pine, birch, other sediments and rocks) have also possibilities of becoming products that could be used in Sollihøgda Plussby, but the longevity indicator for these materials was lower than those of Norway spruce and rhomb porphyry. Despite the usefulness of the longevity indicator to provide a preliminary assessment, this method needs to be upgraded so it incorporates other CE parameters. There should be a distinction on how many times the material is recycled, the lifetime of the recycled products, and the quality of the products obtained from the recycling process. Inventorying the natural resources on a construction site is a practice that should become common, since it allows to determine how materials can be harnessed, but also which areas should be preserved due to their ecological value. Additionally, the longevity indicator should not be used in isolation, but the environmental impacts of each suggested product should be assessed too.

Unsustainable consumption patterns and material scarcity has been recognised as one of the challenges within the European Union. To change these patterns policy makers within EU are looking towards a transitioning into circular economy. Electronics and manufacturers of energy related products is found to be important actors in this transition, due to the unsustainable trends of consumption and the materials of important contained in electronics. Energy related products are regulated by the Eco design directive (Directive 2009/125/EC) containing implementing measures on energy efficacy. Today the directive is lacking methods for assessing material efficacy in energy related products. CEN/CENELEC was 2015 requested to develop standard methods on how to assess the material efficiency aspects; durability, ability to reuse, repair, upgrade, re-manufacturabiliy, recyclability and recoverability and use of recycled content and CRM content. This study sets out to assess the adaptability of the preliminary publications of the standards on to an Ericsson radio network product. The study is divided into two parts, part one assesses the general and product specific implementation of the selected standard documents. The first parts of this study are document analysis and seven interviews used to triangulate the general opinions on the standards. In part two the study sets out to test two of the methods found in the standard documents. The study found in the collection of recycling data and rates for a small radio network product, the product had a recyclability of XX% and a recoverability of XX% and a time for disassembly of XX seconds using the suggested method eDiM. The findings of this study suggest that these standardised methods are welcomed by the telecommunications equipment manufacturer but concerns on the amount of data required, future purpose and the reliability of the assessment methods still creates worries for the future. / Ohållbara konsumtionsmönster och materialbrist har erkänts som en av de största utmaningarna inom europeiska unionen. För att förändra dessa mönster så har beslutsfattare inom EU påbörjat omställningen till den cirkulära ekonomin. Elektronik och tillverkare av energirelaterade produkter har erkänts som viktiga aktörer i denna omställning, på grund av den ohållbara konsumtionsutvecklingen under det senaste decenniet och de viktiga material som används för att tillverka elektronikprodukter. Energirelaterade produkter regleras av Eco design direktivet (direktiv 2009/125 / EG) som idag innehåller implementeringsåtgärder för energieffektivitet i energirelaterade produkter. I framtiden kommer det även finnas implementeringsåtgärder för materialeffektivisering men idag saknas standardiserade metoder för bedömning av material effektivitet. År 2015 tillförordnades CEN/CENELEC uppdraget att ta fram och utveckla standarder för bedömning av materialeffektivitetsaspekterna; livslängd, återanvändning, reparerbarhet, uppgraderingsbarhet, återtillverkning, återvinningsbarhet och användningen av återvunnet material och innehåll av kritiska råmaterial. Den här studien syftar till att analysera användbarheten hos de preliminära publikationerna av standarderna inom ramen för Ericssons verksamhet. Studien är uppdelad i två delar, del ett bedömer det allmänna och produktspecifika genomförbarheten av de utvalda standarddokumenten. Resultatet från del ett baseras på en dokumentanalys och sju intervjuer, som används för att triangulera de generella åsikterna om standarderna. I del två testas två av metoderna ur standarddokumenten. Resultatets av testerna visar att den utvalda nätverksprodukten hade en återvinningsbarhet på XX% och en återhämtning på XX%. Studien visar även att nätverksprodukten hade en tid för demontering på XX sekunder när den föreslagna metoden eDiM användes. Resultaten av denna studie tyder på att dessa standardiserade metoder välkomnas av Ericsson men mängden data, framtida syfte och pålitligheten av bedömningsmetoderna skapar oro för framtiden.

As part of the European Union’s climate commitment including the adoption of the Paris agreement, the European commission has developed a long-term strategy with the goal to reach net zero CO2emissions in 2050. To achieve this, a transformation of the European industry is necessary, as it represents 30% of EU’s total emissions. A major challenge will be to cut emissions in the CO2intensive steel industry, which is considered hard to abate. To reach the Paris agreement, deep emission cuts are necessary to occur within a decade, before cumulative emissions are too high. Today, about 60% of all steel in the EU is produced using coke as feedstock, a process resulting in large CO2 emissions. A new process in which hydrogen is used instead of coke is under development, with no direct CO2 emissions as result. The implementation of such technologies can help shift the production from fossil based to renewable, with declining emissions as a result. Until now, most abatement methods are focused on the supply side, finding technical solutions that can reduce emissions. This study shows that technology can play an important role in the transformation of the steel industry but will not alone achieve the necessary reductions fast enough. To achieve near-zero emissions in the steel industry, the solution set needs to widen to include demand side measures. The results show that circular economy principles that promote higher shares of recycled steel and reduced losses have the potential to lower total demand. This also applies for circular business models, by which incentives for higher utilisation and lifetimes of products can be created. In this report, demand-side measures are analysed using a stock-based steel demand model. It is estimated that demand-side measures can decrease the steel demand by 27% in 2050, compared to a business as usual scenario. Applying circular principles would also increase the share of recycled steel being produced from old steel scrap, a process far less CO2 intensive than virgin production. The findings are, that demand side measures can provide immediate deep emission cuts necessary, saving time before new technologies are implemented. The lower steel demand also helps making the transition from fossil to fossil-free steel production easier. By a combination of demand side reductions and hydrogen-DR the steel industry in Europe can reach near-zero emissions by 2050.

Under de senaste århundradena har samhället tillämpat ett linjärt synsätt på ekonomin där varor produceras, säljs, används och sedan blir till avfall utan någon högre grad av återvinning. Det linjära synsättet har stor inverkan på vår planet med minskade ändliga resurser och ökat klimathot. Fler och fler har fått upp ögonen för att vårt nuvarande synsätt inte är hållbart och som en respons på den ökade medvetenheten har begreppet cirkulär ekonomi växt fram. Cirkulär ekonomi, i motsats till linjär, bygger på att sluta kretsloppen, både biologiskt och tekniskt. Begreppet innebär att minimera råvaruuttaget genom ökad återvinning och återbruk samt minimera avfallet genom att nyttja det som råvara någon annanstans. Syftet med denna studie är att undersöka vilka åtgärder som skulle möjliggöra ett fastighetsföretags omställning från en linjär till en cirkulär affärsmodell. Det innefattar att belysa vilka områden som bör beaktas när cirkulär ekonomi inkorporeras i verksamheten och hur eventuella hinder kan övervinnas. Arbetet har genomförts genom en litteraturstudie där cirkulär ekonomi har undersökts både på generell nivå samt specifikt inom fastighetsbranschen. En intervjustudie har genomförts med fastighetsföretag och andra marknadsaktörer där resultatet visar på tydliga strukturella problem som måste övervinnas för att övergången mot en cirkulär ekonomi ska kunna äga rum. Avsaknaden av en marknadsplats för återbrukade material och produkter är central. Fastighetsbranschen visar på en medvetenhet kring miljöfrågor, kunskapen om hur cirkulär ekonomi ska kunna inkorporeras i verksamheten är dock mindre. Vidare framgår att digitaliseringen kommer vara en drivande faktor där nya digitala tjänster och plattformar möjliggör inte minst för nya delandetjänster och funktioner. Att cirkulär ekonomi måste kunna kopplas till affärsnytta är tydligt och ur övergången mot cirkulär ekonomi uppstår nya affärsmodeller som på sikt kan öka lönsamheten givet att fastighetsägaren i högre grad kan arbeta cirkulärt. / In the last few centuries, society has applied a linear approach to the economy where goods are produced, sold, used and then become waste without a higher degree of recycling. The linear approach has a great impact on our planet with reduced finite resources and increased climate threat. More and more people have become aware that our current approach is not sustainable and as a response to the increased awareness, the concept of circular economy has emerged. Circular economy, in contrast to linear, is based on ending the cycles, both biological and technical. This implies minimizing raw material consumption through increased recycling and reuse and minimize waste by utilizing it as raw material elsewhere. The purpose of this study is to investigate which measures would enable a real estate company to switch from a linear to a circular business model. This includes highlighting which areas should be considered when circular finances are incorporated into the business and how any obstacles can be overcome. A literature study has been conducted in which circular economy has been examined both at the general level and specifically in the real estate industry. Later, an interview study has been conducted with real estate companies and other market participants where the result shows clear structural problems that must be overcome for the transition to a circular economy to take place. The lack of a marketplace for recycled materials and products is central. The real estate industry shows an awareness of environmental issues, however there is less knowledge about how circular economy is to be incorporated into the business. Furthermore, it appears that digitization will be a driving factor where new digital services and platforms are vital enablers, not least for new sharing services and functions. Circular economy must be linked to business benefits and from the transition to circular economy new business models will emerge, which in the future can increase profitability, given that the property owner can work more circularly to a greater extent.

The BCL-2 family of proteins tightly regulates the delicate balance between life and death. The pore forming Bax is a pro-apoptotic member belonging to this protein family. At the onset of apoptosis, monomeric cytoplasmic Bax translocates to the outer mitochondrial membrane, forms oligomeric pores thereby letting mitochondrial cytochrome c enter the cytosol and initiate the apoptotic cascade. The C-terminal "helix 9" is thought to mediate the membrane binding of BAX. A 20-amino acid peptide corresponding to Bax C-terminus (VTIFVAGVLTASLTIWKKMG) and two mutants where the two lysines are replaced with Glu (charge reversal mutant, EE) or Leu (charge neutralization mutant, LL) have been studied to elucidate the pore formation capabilities of Bax C-terminus and the underlying molecular mechanism. Interactions of the wild-type and the two mutant peptides with zwitterionic and anionic phospholipid membranes caused efficient membrane permeabilization, as documented by release of vesicle-entrapped fluorescent indicator calcein. Light scattering experiments showed that vesicles maintained their integrity upon peptide binding, indicating that the content leakage was due to pore formation and not vesicle degradation. Kinetics of calcein release at various peptide concentrations were used to determine the peptide-peptide association constants and the oligomeric state of the pore. The structure of membrane-bound peptides was analyzed by circular dichroism (CD) and attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy. CD data indicated all three peptides reconstituted in lipid vesicles contained [alpha]-helical and [beta]-strand structures. ATR-FTIR experiments indicated that the minimally hydrated samples of peptides in stacked lipid bilayers (absence of bulk water) were mostly [alpha]-helical but adopted mostly [beta]-sheet conformation in the presence of excess water. Finally, the depth of membrane insertion of the peptides was analyzed using tryptophan fluorescence quenching by dibromo-phosphatidylcholines brominated at various positions of their acyl chains. In case of zwitterionc phospholipid membranes, the single Trp¹⁶ was located at ~9 Å from membrane center. In case of membranes containing 30% of an anionic phospholipid, the depth of membrane insertion of the EE mutant was not affected but the wild-type and the LL mutant peptides were embedded much deeper into the membrane, with Trp¹⁶ located at 3-4 Å from membrane center. These results will help achieve a better understanding of the molecular mechanism of membrane pore formation of Bax protein. In addition, they provide insight into the molecular details of membrane pore formation by peptides and could facilitate the design and production of cytotoxic peptides with improved capabilities to lyse cells such as bacteria or cancer cells.

A-B family of toxins consists of plant toxins such as ricin and bacterial toxins such as cholera. The A subunit is the enzymatic domain and the B subunit is the receptor binding domain. Commonly, these toxins bind to the target cell plasma membrane receptors through their B subunit followed by endocytosis and a transport to the endoplasmic reticulum (ER). Inside the ER, the A subunit dissociates from the rest of the toxin, unfolds and triggers the ER quality control mechanism of ER-associated degradation (ERAD). Most ERAD substrates are purged out of the ER into the cytosol for proteasomal degradation. However, the low content of lysine amino acid residues allows the toxin to evade polyubiquitination and subsequent proteasomal degradation. The toxin A subunit refolds into an active conformation in the cytosol, setting off downstream toxic events. In the first part of my thesis, the hypothesis was tested that inhibiting the unfolding of the toxin A subunit inside the ER will prevent ERAD activation, toxin export to the cytosol and intoxication. The chemical chaperones glycerol and sodium 4-phenyl butyrate (PBA) were used to inhibit the toxin A chain unfolding. In vitro biophysical experiments indicated that both chemical chaperones indeed stabilize the cholera toxin A subunit and prevent cytotoxicity. In case of ricin, both chaperones stabilized the toxin A chain but only glycerol prevented cytotoxicity. Additional experiments showed that PBA-treated ricin A chain is destabilized when exposed to anionic lipid membranes mimicking the properties of the ER membrane. In contrast, anionic lipid did not prevent ricin A chain stabilization by glycerol. This explains why glycerol but not PBA blocked ricin intoxication, as only glycerol stabilizes ricin A chain in the presence of ER membranes. Cholera toxin in contrast, remained either unaffected or slightly stabilized in presence of anionic lipids both in presence and absence of PBA. This shows that destabilization by anionic lipids is a toxin-specific rather than a general effect. In the second part of my thesis, the effect of inner leaflet of plasma membrane on the structure of cholera toxin A chain (CTA1) was studied. Since CTA1 refolds into an active conformation in the cytosol in association with unidentified host factors, I hypothesized that inner leaflet of the plasma membrane might play a role to stabilization and/or refolding of CTA1. CTA1 was shown to be a membrane interacting protein, and membranes mimicking lipid rafts had a significant stabilizing effect on its structure. Lipid rafts helped in the regaining of the tertiary and secondary structure of CTA1, while non-raft lipids had a smaller stabilizing effect on CTA1 structure. In the next part of my thesis, I studied the effect of membrane binding on the structure and function of human pancreatic phospholipase A₂ (PLA₂). Lipid thermal phase transition was found to have a dramatic effect on PLA₂ activity. It was also established that although membrane binding and insertion was essential for of PLA₂ activity, lipid structural heterogeneity was more important than the depth of membrane insertion for enzyme activation. Most importantly, significant changes in PLA₂ secondary and tertiary structures were identified that evidently contribute to the interfacial activation of PLA₂. Overall, we conclude that the function of membrane binding enzymes can be significantly modulated via conformational changes induced by interactions with membranes. Thus, we have elucidated various roles of membrane lipids from unfolding and refolding to activation and modulation of membrane binding enzymes. Physical properties of lipids help in regulating various aspects of protein structure and function and their analysis helped us in appreciating the influence wielded by the membrane lipids in the enzyme's surrounding environment.

Nozzles are used in a wide range of applications. Nevertheless, the geometric of non-circular orifices have not been widely studied. This project has examined fluid jets exiting through a non-circular orifice, in the gravitational direction. Furthermore, its transformation to a circular cross-section due to a surface tension forces. How the length to a circular cross-section changes with the nozzles geometry and bath depth of the tundish was the main focus of this studied. A water model and high-speed camera was used to capture the profile of the fluid jet. Four different nozzles were attached one by one to five different tundishes with different bath depths. The result showed that with deeper bath depths the circular cross-section occurred further down from the nozzles orifice. The length to the circular cross-section also depended on the orifice area, a larger area gave a longer distance than a smaller area. It was shown that the length to circular cross-section followed a quadratic function, when the measured values were analyzed based on the Weber number. The profile of the fluid jet was dependent on the material of the nozzle, the geometries of the orifice, the bath depth and the surface tension.

The purpose of our thesis is to determine to what extent the cow milk and oat drink industries can implement a circular economy according to Ellen MacArthur Foundation’s definition. In addition, we will discuss the impact on the overall sustainability.  31% of the anthropogenic emissions stem from processes related to food production and in Sweden, a significant portion of these stem from the dairy industry– which has also been noticed by some oat drink companies. The problem is further amplified by the fact that a third of the food produced for human consumption ends up lost or wasted. Multiple laws and policies have been introduced to combat this, and new solutions are needed. A term that has gained popularity lately is the circular economy, which focuses on closing the loop and thus eliminating waste. That way, if would be possible to see the environmental impact from the oat drink and cow milk industries in a bigger perspective.  We have conducted a qualitative study using primary and secondary data. The primary data stems from 11 semi-structured interviews and the secondary data comes from relevant documents by the companies. An inductive approach was used.  The results showed that it is not possible for these industries to implement an entirely circular food supply chain because of the inevitable food waste. Overall, there is also a lack of terminology and measuring methods in both areas related to the CE. Yet, the work with food waste has come far within the individual companies but the coordination between companies that will allow them to cooperate requires further attention. The efforts should be aimed at the consumer level and seek to clarify the question of responsibility. Furthermore, the difficulties in profitability must be solved, and an improved compensation system is needed. Finally, we noted that a circular economy is not by definition perfectly sustainable, and that changes in the oat drink can lead to other implications of a study like this one.

The purpose of the study was to evaluate the merits of the DiscRotor concept that combine the features of a retractable rotor system for vertical take-off and landing (VTOL) with an integral, circular wing for high-speed flight. Tests were conducted to generate basic aerodynamic characteristics of the DiscRotor in hover and in fixed-wing flight. To assess the DiscRotor during hover, small scale tests were conducted on a 3ft diameter rotor without the presence of a fuselage. A "hover rig" was constructed capable of rotating the model rotor at speeds up to 3,500 RPM to reach tip speeds of 500fps. Thrust and torque generated by the rotating model were measured via a two-component load cell, and time averaged values were obtained for various speeds and pitch angles. It has been shown that the DiscRotor will perform well in hover. Ground Effects in hover were examined by simulating the ground with a movable, solid wall. The thrust was found to increase by 50% compared to the ground-independent case. Pressure distributions were measured on the ground and disc surfaces. Velocity measurements examined the flow field downstream of the rotor by traversing a seven hole velocity probe. A wake behind the rotor was shown to contract due to a low pressure region that develops downstream of the disc. Wind tunnel experimentation was also performed to examine the fixed wing flight of the DiscRotor. These experiments were performed in the VA Tech 6â X6â Stability Tunnel. A model of the fuselage and a circular wing was fabricated based upon an initial sizing study completed by our partners at Boeing. Forces were directly measured via a six degree of freedom load cell, or balance, for free stream velocities up to 200fps. Reynolds numbers of 2 and 0.5 million have been investigated for multiple angles of attack. Low lift-to-drag ratios were found placing high power requirements for the DiscRotor during fixed-wing flight. By traversing a seven-hole velocity probe, velocities in a 2-D grid perpendicular to the flow were measured on the model. The strengths of shed vortices from the model were calculated. A method to improve fixed-wing performance was considered where two blades were extended from the disc. An increase of 0.17 in the CL was measured due to the interaction between the disc and blades. This research utilized a wide range of experiments, with the aim of generating basic aerodynamic characteristics of the DiscRotor. A substantial amount of quantitative data was collected that could not be included in this document. Results aided in the initial designs of this aircraft for the purpose of evaluating the merit of the DiscRotor concept. / Master of Science