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Near-Earth asteroids (NEAs) are celestial objects whose perihelion is distinctively in the inner Solar System. As these objects orbit the Sun mainly outside of the main belt, they are a separate category of asteroids. A fraction of these asteroids is especially interesting due to their small albeit existing impact probability with Earth. As acts of constant attention and interest toward NEAs, several probes have been sent to study the objects. Since the 1990s, astronomers have discovered moons orbiting asteroids. These asteroid moons also exist in the NEA population. A fraction of the primary components of binary asteroids rotates especially fast. A cause for the fast spin rates is the Yarkovsky–O’Keefe–Radzievskii–Paddack (YORP) effect that affects the rotational period of irregularly shaped asteroids. Moreover, some asteroid moons may form due to the solar radiation phenomena of the YORP effect. Additionally, the Yarkovsky effect caused by thermal re-emission influences the orbits of NEAs over long time periods. A third potentially influencing solar radiation effect is the binary YORP (BYORP) effect, an explanatory theory for the relatively short life spans of asteroid moons. The thesis discusses NEAs, emphasizing binary asteroids, their formation, and observations. Ground-based equipment is used for a significant number of asteroid observations, making the fields interconnected. Optical telescopes and planetary radars offer diverse information on NEAs, whose discovery rates and orbital analysis have progressed prominently since the 1990s. As a case study of the observation methods, I discuss the ternary system (3122) Florence and its close encounter in September 2017 in the thesis.

This thesis is an exploration of food delivery couriers’ everyday experiences, practices and sensemaking processes through a posthumanist and sociomaterial approach that highlights the idea that technology and society are mutually shaping one another, and that considers the agency of non-human entities such as algorithms, transcendental. Moreover, by adopting a sociomaterial perspective, we can have a better understanding of how social and technological systems, as well as human and non-human beings, are interrelated, how they shape, and are shaped by one another. This work’s aims are threefold: First, it explores couriers’ experiences at work and describes their daily practices in order to understand the enactment of agency from a sociomaterial and post-humanist philosophical tradition. Second, it explores the material implications of algorithmic management in couriers’ lives, and finally, it explores the way couriers perform their work in context, both through the tethered geographical elements of the city, and amidst the platform’s multiple entanglements and spatiotemporal arrangements. The research design of this thesis has a strong qualitative research methodology, including methods such as walk-along interviews, semi-structured interviews, ethnographic reporting techniques, and the author’s 3-month work experience as a food delivery courier. The findings of this work suggest that we should acknowledge the platform as a constant becoming entity where couriers’ sensemaking processes are produced at the intersection of their experience of the city and their relationship with the managing algorithms of the platform. A performative sociomaterial practice that constantly produces knowledge that is used by couriers to negotiate their participation in the platform. This thesis expands previous understandings of digital workers’ experiences of algorithmic management by incorporating a sociomaterial and performative approach in the analysis of couriers’ sensemaking processes. Furthermore, by considering the relationships and interactions between human and nonhuman agencies in the food delivery platform industry, this work contributes not only to the understanding of agency within digital platforms but also to a broader understanding of agency in our increasingly digitally mediated societies.

Bioortogonaaliset reaktiot ovat reaktioita, jotka eivät käytä katalyytteinä myrkyllisiä aineita, mutta tapahtuvat nopeasti ja selektiivisesti pienissä konsentraatioissafysiologisissa ympäristöissä. Tällaisia reaktioita ovat esimerkiksi Staudingerin ligaatio ja IEDDA sykloadditio. Staudingerin ligaatiossa atsidi ja fosfiini reagoivat muodostaen stabiilin amidisidoksen. Staudingerin ligaation hidas reaktionopeus ei mahdollista reaktion toteuttamista in vivo. Toinen bioortogonaalinen reaktio, jolla puolestaan on erittäin nopea kinetiikka, ja joka pystytään toteuttamaan in vivo, on IEDDA sykloadditio. Tämä reaktio tapahtuu dienofiilin ja tetratsiinin välillä muodostaen pyridatsiinin. Tämän työn tarkoituksena oli syntetisoida rodamiinijohdannainen. Rodamiinit ovat orgaanisia fluoroforeja, joiden ominaisuuksiin kuuluu muun muassa vähäinen pH herkkyys, vesiliukoisuus ja säädettävät spektriominaisuudet. Viime vuosina tutkimus on kohdistunut fluoroforeihin, joiden fluoresenssi voidaan himmentää ja kytkeä takaisin päälle. Tämän tutkimuksen tarkoituksena on kehittää multimodaalinen, radioleimattu ja fluoresoiva merkkiaine, jonka fluoresenssi voidaan himmentää tetratsiinin avulla Through Bond Energy Transfer -mekanismilla, ja myöhemmin kytkeä takaisin päälle, sekä tehdä radioaktiiviseksi IEDDA sykloadditiolla radioleimatun transsyklo-okteenin kanssa. Merkkiaine voidaan liittää solukalvolle istutettuun atsidiin in vitro Staudingerin ligaatiolla. Radioaktiivisella ja fluoresoivalla merkkiaineella leimattuja soluja voidaan seurata elävässä eläimessä ensin PET kuvantamisella ja myöhemmin kudosnäytteessä fluoresenssin avulla. Tässä työssä syntetisoitiin rodamiinijohdannaisen kahden rakenneisomeerin seos. Synteesissä 3-dimetyyliaminofenolin ja 4-bromoftalaatin seosta refluksoitiin 25 tuntia propionihapon ja metaanisulfonihapon läsnäollessa. Synteesin jälkeen isomeerit erotettiin toisistaan, sillä vain molekyylin meta-asemassa oleva tetratsiini pystyy himmentämään fluoresenssin tehokkaasti. Isomeerien samankaltaisuuden ja molekyylien ominaisuuksien takia isomeerien erottaminen oli haastavaa. Erottamista ja puhdistamista yritettiin useilla eri kromatografisilla menetelmillä. Lopulta erottaminen onnistui manuaalisella nestekromatografialla, käyttäen kiinteänä faasina neutraalia aluminaa. Isomeerien tunnistamisessa ja analyysissä käytettiin LC-MS menetelmää, sekä NMR-spektrometriaa.

Physical Vapour Deposition (PVD) is a method of thin film deposition that involves transport of materials in the gas phase through physical means. The greatest advantage of using PVD is its ability to deposit hard coatings that are almost impossible to deposit by other liquid or chemical deposition methods. The applications of PVD include semiconductor devices, cutting and drilling tools, optical coating for displays, and decorative coatings for jewellery. When PVD process is accompanied by a separate (noble) gas ion bombardment, it is termed as Ion Beam Assisted Deposition (IBAD). These two processes can be subjected to atomistic simulation as opposed to conventional experimental methods. The idea behind such a simulation is the level of control in terms of material purity, dimensionality and simulation parameters. In this simulation work, the growth and overall morphology of epitaxial growth of copper film under both PVD and IBAD is considered. The film roughness and intrinsic stress are subjected to testing under various deposition energies in PVD. The same properties are also tested under variation of bombardment energies, and bombarding rates or ion fluence in IBAD. The results show that the nature of the film growth is primarily dependent on the deposition energy. In PVD, low deposition energies lead to growth dominated by island growth, while high deposition energies are mainly layer-by-layer growth dominated. In IBAD done at a constant low atom deposition energy, a similar trend is seen with an increasing argon ion bombardment energy at 0.5 ions/nm2 fluence. Since the deposition energy of 1 eV is geared towards island growth, the conversion rate of island like structures to relatively layer-by-layer structure depends on the ion bombardment energy (IBAD case). By comparison of IBAD and PVD outcomes, it has been established that the best layered PVD film occurs at a deposition energy of 30 eV. The overall film quality (in PVD) with respect to layer-by-layer growth is much better than that deposited using IBAD at similar bombardment energy at an ion fluence 0.5 ions/nm2. However, to attain a comparable or superior layer-by-layer growth as PVD, IBAD process has to be conducted at a much higher bombardment energy (50 eV) at fluence of 0.5 ions/nm2. The other alternative is to undertake IBAD process at bombardment energy of 30 eV, and at a much higher ion fluence. At a fluence of 0.8 ions/nm2 and equivalent ion bombardment energy (30 eV) produces a far much superior structure to PVD growth. The tradeoff between which ion fluence to use in IBAD is the deposition rate. Higher ion fluence translates to slow deposition but much improved layer-by-layer structure. The stress profile shows a decreasing stress profile as a function of thickness as predicted by Stoney's equation. At non-equilibrium deposition conditions, the film is generally stressed. However, under optimal conditions for layer-by-layer growth, IBAD grown films are generally less stressed in comparison to PVD.

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