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Mammography is used as an early detection system for breast cancer, which is one of the most common types of cancer, regardless of one’s sex. Mammography uses specialised X-ray machines to look into the breast tissue for possible tumours. Due to the machine’s set-up as well as to reduce the radiation patients are exposed to, the number of X-ray measurements collected is very restricted. Reconstructing the tissue from this limited information is referred to as limited angle tomography. This is a complex mathematical problem and ordinarily leads to poor reconstruction results. The aim of this work is to investigate how well a neural network whose structure utilizes pre-existing models and known geometry of the problem performs at this task. In this preliminary work, we demonstrate the results on simulated two-dimensional phantoms and discuss the extension of the results to 3-dimensional patient data.

Tutkielmani käsittelee goodwill-vahingon korvaamista kansainvälisen tavaran kaupan kontekstissa nk. YK:n kauppalain (CISG) vahingonkorvaussäännösten mukaan. Goodwill voidaan käsittää sopimusosapuolen kaupalliseksi maineeksi, jonka vahingoittuminen sopimusrikkomuksen seurauksena voi aiheuttaa haltijalleen välillistä taloudellista vahinkoa. CISG artikla 74 ei eksplisiittisesti määrittele goodwill-vahinkoa konvention mukaan korvattavaksi vahingoksi, mutta vahinkolaji voi oikeuskirjallisuudessa vallitsevan kannan mukaan tulla korvattavaksi. Korvauksen saamisessa goodwill-vahingosta ilmenee kuitenkin käytännön ongelmia, sillä esimerkiksi vahingon luonnetta ja sen näyttämiseen liittyvää problematiikkaa ei ole käsitelty kattavasti oikeuskäytännössä tai oikeudenalan keskeisessä kirjallisuudessa. Tutkielmani käsittelee pääasiassa CISG artiklan 74 pohjalta kolmea pääkysymystä: 1) millaisessa muodossa goodwill-vahingon tulee ilmetä, jotta se on CISG:n mukaan korvattava vahinko, 2) milloin kyseinen vahinko on ennakoitavissa sopimuksen- tekohetkellä, ja 3) miten goodwill-vahinko tulee näyttää korvauksen saamiseksi. CISG artikla 74 määrittelee vahingonkorvaukseksi rahamäärän, joka vastaa sopimusrikkomuksen vuoksi toiselle sopijapuolelle aiheutunutta vahinkoa, menetetty kauppavoitto mukaan lukien. Yleiseksi rajoitukseksi korvattavaksi tuleville vahingoille artikla säätää vahingon ennakoitavuuden vaatimuksen: vahingonkorvaus ei saa olla suurempi kuin se vahinko, jonka sopimusta rikkonut osapuoli sopimusta tehtäessä ennakoi tai joka hänen olisi pitänyt ennakoida sopimusrikkomuksen seuraukseksi niiden tosiasioiden tai seikkojen valossa, jotka hän silloin tunsi tai jotka hänen olisi pitänyt tietää. Sovellettava vastuuperuste on ankara vastuu force majeure -poikkeuksin ja lähtökohtana vahinkoa kärsineen osapuolen korvauksen laskemiselle on täyden korvauksen periaate. Ensimmäinen tutkimuskysymys pohtii goodwill-vahingon aineetonta ja toisaalta taloudellista puolta. Oikeudenalan kirjallisuudessa vahinkolajia on käsitelty sekä aineettomana että taloudellisena vahinkona. Tutkielma esittää, että kaupallinen maine sinänsä on luonteeltaan aineetonta, mutta maineen vahingoituttua sopimusrikkomuksen seurauksena voi vahinkoa kärsineelle osapuolelle syntyä taloudellinen vahinko, joka johtuu esimerkiksi asiakkaiden ja siten kauppavoiton menetyksestä. Johtopäätöksenä siitä, millaisessa muodossa goodwill-vahingon tulee ilmetä, jotta se olisi CISG:n mukaan korvattava vahinko, esitetään, että vahingon tai sen seurausten tulee ilmetä taloudellisena vahinkona eli rahallisena menetyksenä, jotta vahinkoa kärsinyt osapuoli voi saada vahingostaan korvauksen. Keskeisenä perusteena johtopäätökselle esitetään CISG artiklan 74 sanamuotoa. Toinen tutkimuskysymys käsittelee goodwill-vahingon ennakoitavuutta sopimuksentekohetkellä. Oikeudenalan keskeisessä kirjallisuudessa ei vallitse yksimielisyyttä siitä, miten asiaa tulisi tarkastella. Kirjallisuudessa esitetään yhtäältä, että goodwill- vahingolle alttiina olevan osapuolen olisi aina ilmoitettava sopimuskumppanilleen kyseisestä riskistä sopimuksentekohetkellä, jotta vahinko voisi olla ennakoitava ja siten tulla korvattavaksi. Toisaalta esitetään, että vahinkolajia voidaan käsitellä yleisesti ennakoitavana. Tutkielma pohtii lähestymistapojen perusteltavuutta ja esittää, että goodwill-vahinkoa tulisi käsitellä yleisesti ennakoitavana ainakin silloin, kun tapauksen erityiset olosuhteet puoltavat vahingon ennakoitavuutta ilman erityistä ilmoitusta kyseisen vahingon riskistä. Myös tälle lähestymistavalle esitetään perusteluksi CISG artiklan 74 sanamuotoa, jonka mukaan ennakoitavuuden piiriin kuuluvat sellaiset vahingot, jotka sopimusta rikkoneen osapuolen olisi pitänyt ennakoida. Tutkielma esittää, että sanamuoto asettaa kansainvälisen kaupan toimijoille tietyn minimiedellytyksen mahdollisten vahinkolajien ennakoitavuudesta. Kolmas tutkimuskysymys perehtyy goodwill-vahingon näyttämiseen. Tutkielma esittää ensinnäkin, että goodwill-vahingon näyttämistä koskevat kysymykset kuuluvat CISG:n soveltamisalaan. Oikeuskirjallisuudessa esitetyn kannan mukaan vahinkoa kärsineen osapuolen tulee näyttää vahinkonsa kohtuullisella varmuudella. Luvussa käsitellyn oikeuskäytännön perusteella voidaan kuitenkin todeta, että goodwill-vahinkoon käytännössä sovellettava näyttökynnys on tätä korkeampi.

The thesis discusses algorithms for the minimum link path problem, which is a well known geometric path finding problem. The goal is to find a path that does the minimum number of turns amidst obstacles in a continuous space. We focus on the most classical variant, the rectilinear minimum link path problem, where the path and the obstacles are restricted to the directions of the coordinate axes. We study the rectilinear minimum link path problem in the plane and in the three-dimensional space, as well as in higher dimensional domains. We present several new algorithms for solving the problem in domains of varying dimension. For the planar case we develop a simple method that has the optimal O(n log n) time complexity. For three-dimensional domains we present a new algorithm with running time O(n^2 log^2 n), which is an improvement over the best previously known result O(n^2.5 log n). The algorithm can also be generalized to higher dimensions, leading to an O(n^(D-1) log^(D-1) n) time algorithm in D-dimensional domains. We describe the new algorithms as well as the data structures used. The algorithms work by maintaining a reachable region that is gradually expanded to form a shortest path map from the starting point. The algorithms rely on several efficient data structures: the reachable region is tracked by using a simple recursive space decomposition, and the region is expanded by a sweep plane method that uses a multidimensional segment tree.

Effective utilization of organic materials can advance the transition away from fossil dependency which is critical in order to restrict the global increase in temperature. Household biowaste can be reutilized through anaerobic digestion to produce organic nitrogen fertilizers for agriculture, which reduces the large, often fossil-based, energy inputs required in the production of synthetic nitrogen fertilizers. Properly recycled biowaste can additionally be used as a raw material for biogas, which can be used as an alternative for fossil-based energy sources. Regardless of these considerable opportunities, large amounts of household biowaste remains unrecycled. Though previous research has shown that recycling behavior is a result of several factors and cannot be depicted entirely accurately, different interventions have demonstrated their capability to improve recycling performance. These interventions have the ability to change either one or more of the three domains that have been theorized to be critical for any behavior to happen: capability, opportunity and motivation. This thesis strives to understand behavioral barriers for biowaste recycling in households and propose targeted behavioral change interventions in Helsinki metropolitan region where nearly 40% of the household mixed waste was unrecycled biowaste in 2021. This is done by analyzing the data derived from an external consumer behavior survey commissioned by Helsinki Region Environmental Services and conducted by Innolink. This research focuses on evaluating the suitability of nudges, enablement, incentives and communication/marketing through social media as means to enhance biowaste recycling performance in Helsinki metropolitan region based on the results from the data-analysis. Area specific research on behavior barriers is required to introduce suitable interventions as recycling behavior is complex and behavior barriers might vary between different groups. Results from this research show that household biowaste recycling performance can be enhanced by using nudges to improve social opportunity as well as automatic motivation, service provision to improve physical opportunity, fiscal measures to improve automatic-, and reflective motivation, and social media to improve reflective motivation. Successful delivery of these interventions can advance the fulfillment of the requirement in the HSY area that oblige biowaste separation in residential properties.

Following the collapse of the Soviet Union, Kyrgyz society got entangled in discussions about what it means to be Kyrgyz. Even though Kyrgyzstan has experienced a surge in nationalism over the last decades, it is only since recently that non-heteronormative sexualities are increasingly constructed as a threat to the continued existence of the Kyrgyz nation. Based on five in-depth interviews with Lesbian, Gay, Bisexual and Transgender (LGBT) individuals, I explore how they rationalise the increasing homophobia in Kyrgyz society and what kind of behavioural strategies they adopt to cope with the hostile environment. In particular, I assess whether the discursive exclusion of LGBT individuals from the Kyrgyz nation alters their relationship with the nation and the state. The research participants demonstrate an awareness for the connection between increasing nationalism and worsening attitudes against LGBT people and report corresponding adjustments in their behaviour, ranging from adaptation and hiding strategies to activism and emigration. While all respondents have a negative relationship with the Kyrgyz state, most report a decreasing sense of belonging to the Kyrgyz nation amid growing homophobia as well. These results suggest that the increased emphasis on the purportedly heteronormative nature of the Kyrgyz nation succeeds in redefining individual belonging to the nation and shifting the imagined boundaries of the nation.

This thesis analyses the alterations of vertically integrated atmospheric meridional energy transport due to polar amplification on an aqua planet. We analyse the energy transport of sensible heat, latent energy, potential energy and kinetic energy. We also cover the energy flux of the mean meridional circulation, transient eddies and stationary eddies. In addition, we also address the response of the zonal mean air temperature, zonal mean zonal wind, zonal mean meridional wind, zonal mean stream function and zonal mean specific humidity. Numerical model experiments were carried out with OpenIFS in its aqua planet configuration. A control (CTRL) and a polar amplification (PA) simulation was set up forced by different SST (sea surface temperature) patterns. We detected tropospheric warming and atmospheric specific humidity increase 15-90° N/S and reduction of the meridional temperature gradient throughout the troposphere. We also found reduced strength of the subtropical jet stream and slowdown of the mean meridional circulation. Important changes were identified in the Hadley cell: the rising branch shifted poleward and caused reduced lifting in equatorial areas. Regarding the total atmospheric vertically integrated meridional energy transport, we found reduction in case of the mean meridional circulation and transient eddies in all latitudes. The largest reduction was shown by the Hadley cell transport (-15%) and by midlatitude transient eddy flux (-23%). Unlike most studies, we did not observe that meridional latent energy transport increases by polar amplification. Therefore, it is stated that the increased moisture content of the atmosphere does not imply increased meridional latent energy transport, and hence there is no compensation for the decrease of meridional dry static energy transport. Lastly, we did not detect stationary eddies in our simulations which is caused by the simplified surface boundary (i.e. the water-covered Earth surface). The main finding of this thesis is that polar amplification causes decreasing poleward energy transport on an aqua planet.

The Red List Index (RLI) has widely been recognized as a useful tool in keeping track of extinction risk trends of large taxa. The RLI is an index based on IUCN’s threat categories. Functional diversity (FD) is a way of measuring biodiversity that describes species´ traits that are linked to species´ ecological roles. In this work I have mapped the spatial distribution of the RLI and functional diversity for Finnish vascular plants. I first produced species distribution models (SDMs) for all 1194 species of vascular plants in the Finnish Red List 2010 based on records from the Kastikka and Hertta databases and environmental data. A functional tree incorporating 971 of those species was calculated using seven functional traits. The traits that I used were life form, maximum plant height, seed mass, seedbank longevity, life span, specific leaf area (SLA), and leaf dry matter content (LDMC). The trait data was gained from the databases Leda and TRY. Based on the SDMs, the functional tree, and the Finnish Red List, taxonomic and functional diversity and RLI were mapped for the whole of Finland using 10 x 10 km cells. This was the first time FD and RLI were mapped for vascular plant species across Finland. Null models were used to compare observed values with the ones expected if species (and consequently traits) distributions were random accross the country. Taxonomic diversity (TD) was higher than expected in southern Finland and lowest in northern Finland, suggesting a strong latitudinal gradient. TD correlated with the same environmental variables as FD. Thus, it is likely that both TD and FD are dirven by the same environmental variables. FD was higher than expected in southern and western Finland and lower in the northern and eastern parts of the country. A strong environmental filtering in the north might cause low FD by limiting species´ distributions within many clades and favouring species with similar traits that allow them to survive in extreme conditions. In southern Finland, competitive exclusion might limit the co-existence of species with similar traits, thus increasing trait divergence. The RLI values were lowest in the Åland islands, along the southern coast, in a few sites in eastern Finland (e.g. Koli and Kuusamo areas), around Kemi and the Gulf of Bothnia and in Kilpisjärvi. Thus, these sites have high concentrations of threatened species. The low RLI sites correspond well with areas with either limestone or dolomite deposits, which explains why many of these areas are floristically unique and present high concentrations of threatened species. In addition, many of the sites with low RLI are geographical extreme areas in Finland, corresponding to the distribution limits of many species. The RLI was high in Ostrobothnia and in large parts of Lapland. In Ostrobothnia, centuries of forest management and a homogenous bedrock and topography have resulted in a vascular plant community based mostly on common species. It is possible, that regional extinctions have happened in Ostrobothnia already before red listing measures began, thus explaining the high RLI values today. On sites with more variety among habitats and bedrock, the RLI values were significantly lower than in the rest of Lapland, suggesting that the high RLI values for parts of Lapland are due to homogeneous plant communities in the northern boreal forests that host only few threatened species. The spatial distribution of the RLI and functional diversity for vascular plants in Finland were mapped for the first time. A strong latitudinal gradient was found for TD and FD. Low RLI values were found on calcareous soils and on geographic extremes in Finland. To track possible changes in the RLI it would be crucial to remap the RLI in 2019 when the next Finnish Red List is published. A comparision between this work and the remapping based on the 2019 assessment would track changes in the extinction risk across Finland. The current limitation with RLI is that it only considers taxonomic diversity. However, in future work it is possible to incorporate the functional tree used in this thesis into RLI to calculate a functionally weighted RLI.

Tiivistelmä – Referat– Abstract Covid-19 conspiracy theories have figured actively in the media and the public debate during the first two years of the pandemic. One of the main functions that such conspiracy theories of society and politics perform is cultural work – they create new representations of reality that give rise to new identities and collectivities. Researchers are increasingly interested in exploring how conspiracy theories come to be so compelling and how people through them create meaning and construct their identities. Qualitative studies that examine the contents of these conspiracy theories and the possibilities for identity construction that they provide are of crucial importance in forming such an understanding. This thesis responds to appeals from researchers to investigate the ways in which gendered identities are implicated in modern conspiracy theories. Critical discursive psychology is employed as a theoretical framework to explore the ways in which men and women are positioned in a Covid-19 conspiracy theory discourse. The material consists of video recordings of two online conferences where 29 influential actors of 9 different nationalities discuss the pandemic as a conspiracy. The results indicate that the Covid-19 conspiracy theory, as represented in the seminars, largely possesses similar characteristics as modern conspiracy theories more generally, blending political subject matter with spiritual or religious descriptions. The pandemic is depicted as confirmation for the existence of a global totalitarian conspiracy that is escalating into an apocalyptic scenario, a development that can only be averted if humanity undergoes a spiritual awakening, collectively reclaiming their individuality and agency. Men and women are positioned differently within this story. Women are positioned primarily as mothers, whose duty it is to protect their children from the conspiracy, as well as to inspire other women to do the same. This maternal identity is depicted as empowering, spiritual and influential, representing a compelling subject position. In addition, the pandemic, that has placed restrictions on the public sphere, is depicted as a threat to a hegemonic masculinity that emphasizes the role of men as providers and (violent) protectors. Men are positioned as effeminate weaklings who have capitulated to the Covid-19 conspiracy without putting up a fight. A return to traditional, heteronormative gender roles is thus represented as central to resisting the conspiracy. The study provides insight into the ways in which gender identity contributes to the formation of modern conspiracy theories and collectives, and particularly into how feminine identities may be engaged in a right-wing populist, anti-conspiratorial political project.

Microplastic pollution is a globally increasing issue in both terrestrial and aquatic environments. One of its pathways to ecosystems is urban wastewater, as the treated effluent has been observed to contain remarkable quantities of plastic particles. In addition, as the treatment process separates the nutrients and solids into a sludge, the particles have been found in the sludge as well. The aim of this thesis is to investigate the costs of removing microplastic particles from the wastewater, and to assess the total microplastic pollution mitigation potential of selected wastewater treatment and sludge management methods. To examine this, I conducted a cost-effectiveness analysis, in which I constituted five different technology scenarios and calculated their incremental cost-effectiveness ratios. The ratios were then compared against a business-as-usual baseline scenario and each other to define the lowest cost of removing microlitter. The cost-effectiveness analysis was conducted for four different wastewater treatment plant sizes. The technology scenarios constituted of combinations of three wastewater treatment and two sludge management methods. The wastewater treatment methods were conventional activated sludge, rapid sand filtering and membrane bioreactor, and the sludge management methods were anaerobic treatment followed by land application as a fertilizer, and sludge incineration. The cost data on the selected wastewater treatment and sludge management methods were obtained from various documented sources, whereas two studies on the microlitter content in wastewater (Talvitie et al., 2017a & 2017b) comprised the effect data. To achieve an overview of the magnitude and the mitigation capacity of the issue, I compared the costs and the quantity of released microlitter of each technology scenario to the baseline scenario. In addition, to assess the impact of changing economic attributes and wastewater quality on the cost-effectiveness ratios, I performed a univariate sensitivity analysis. The results of the analyses prove that removing microplastics from wastewater is both feasible and cost-effective. The membrane bioreactor combined with sludge incineration resulted the most economical scenario in all circumstances and in each wastewater treatment capacity.

Hiukkasfysiikan standardimalli kuvaa alkeishiukkasia ja niiden välisiä vuorovaikutuksia. Higgsin bosonin löydön (2012) jälkeen kaikki standardimallin ennustamat hiukkaset on havaittu. Standardimalli on hyvin tarkka teoria, mutta kaikkia havaittuja asioita ei voida kuitenkaan selittää standardimallin puitteissa. Supersymmetria on yksi houkutteleva tapa laajentaa standardimallia. Matalan energian supersymmetriaa ei kuitenkaan ole havaittu. Supersymmetria vaatii toimiakseen niin sanotun kahden Higgsin dubletin mallin. Tavallisessa standardimallissa on yksi Higgsin dublettikenttä. Higgsin dubletissa on kaksi kompleksista kenttää eli yhteensä neljä vapausastetta, joten voisi olettaa, että siitä syntyy neljä hiukkasta. Kolme vapausasteista kuitenkin sitoutuu välibosoneihin W+, W− ja Z, jolloin jäljelle jää yksi Higgsin bosoni. Kahden Higgsin dubletin malleissa dublettikenttiä on kaksi. Koska se lisää teoriaan yhden neljän vapausasteen dubletin, Higgsin hiukkasia on siinä kaiken kaikkiaan viisi: kolme sähköisesti neutraalia (h, H ja A) sekä kaksi sähköisesti varattua (H+ ja H−). Tässä työssä keskitytään varattujen Higgsin hiukkasten etsintään malliriippumattomasti. Tutkimuksessa käytetään LHC-kiihdyttimen (Large Hadron Collider, suuri hadronitörmäytin) CMS-ilmaisimen (Compact Muon Solenoid, kompakti myonisolenoidi) keräämää dataa. Sähkövarauksellisten Higgsin bosonien etsintä keskittyy lopputiloihin, joissa varattu Higgsin bosoni hajoaa hadroniseksi tau-leptoniksi (eli tau-leptoniksi, joka puolestaan hajoaa hadroneiksi) sekä taun neutriinoksi. Niin sanottu liipaisu on tapa suodattaa dataa tallennusvaiheessa, sillä dataa tulee törmäyksistä niin paljon, ettei kaiken tallentaminen ole mahdollista. Eri liipaisimet hyväksyvät törmäystapauksia eri kriteerien perusteella. Liipaisusta aiheutuu merkittäviä systemaattisia epävarmuuksia. Tässä työssä liipaisun epävarmuuksia pyritään pienentämään käyttämällä sellaisia liipaisimia, joiden epävarmuudet ovat pienempiä. Tätä varten analyysi on jaettava riippumattomiin osiin, joiden epävarmuudet käsitellään erikseen. Lopuksi osat yhdistetään tilastollisesti toisiinsa, jolloin kokonaisepävarmuuden oletetaan pienenevän. Tässä työssä tutkitaan, pieneneekö tämä epävarmuus ja kuinka paljon. Näitä menetelmiä käyttäen kykenimme löytämään pieniä parannuksia analyysin tarkkuuteen raskaiden varattujen Higgsin bosonien kohdalla. Lisäksi odotettu raja, jota suurempi varatun Higgsin hiukkasen tuotto tässä lopputilassa olisi havaittavissa, paranee yllättävästi. Tätä rajan paranemista tutkitaan liipaisua emuloimalla. Työ on tarkoitus sisällyttää koko Run2:n datasta julkaistaviin tuloksiin.