Laser-interferometric analysis of surface acoustic wave resonators

The research work described in this Thesis concentrates on studying surface acoustic wave (SAW) resonators, in particular resonators which utilize the leaky surface acoustic wave (LSAW) mode. Such resonators constitute building blocks for radio-frequency SAW bandpass filters, which are widely employed in modern cordless and cellular telecommunication systems. The number of radio frequency SAW filters produced presently exceeds 3 billion per year. The work is carried out with an optical Michelson laser interferometer developed at the Materials Physics Laboratory specifically for the purpose of studying SAW components. In the course of this work the interferometer was equipped with a high-speed photodetector and state-of-the-art detection electronics, enabling the measurement of surface vibrations at frequencies as high as 2 GHz with amplitudes on the order of a few picometers. Furthermore, the setup was equipped with high-precision motorized scanning stages and computer control in order to facilitate automatically performed two-dimensional scans with a large number of scanning points and measuring speeds up to 50 000 points per hour. The optical setup features a spatial resolution better than one micrometer, enabling measurement of surface waves with wavelengths down to 2 micrometers. The interferometer can be used for analysis of surface acoustic wave devices as well as for thin-film bulk acoustic wave resonators and radio-frequency microelectromechanical systems (RF-MEMS). Laser-interferometric measurements were performed on LSAW resonators and filters on rotated Y-cut lithium tantalate (LiTaO3). As a result, an unexpected acoustic field distribution was observed. Further measurements and simulations showed that the observed field distributions resulted from LSAWs escaping outside the resonator into the busbars. This acoustic loss mechanism can significantly degrade the performance of an LSAW filter. The obtained results have been acknowledged by SAW filter manufacturers in Japan and in Europe. In addition, measurements of bulk acoustic wave (BAW) radiation from LSAW resonators were carried out. Such radiation is inherent for LSAW resonators. Theoretical models and numerical simulations characterizing the phenomenon exist but very few direct measurements have been reported. Here, direct measurement results of BAW radiation fields generated by an LSAW resonator on LiTaO3 are reported revealing both fast shear and slow shear bulk waves. Furthermore, two coupling mechanisms, backscattering and direct excitation, were identified. Such information can be used in the development of more accurate simulation models.reviewe

Intratumoral androgen biosynthesis in prostate cancer: Evidence from preclinical models and clinical specimens

Androgens regulate the growth and development of normal prostate and prostate cancer. Blocking the production and effects of androgens, either by castration or medication, has been the most efficient strategy for treating metastatic prostate cancer for decades. Although most patients respond to the therapy, in many of them the disease progresses to castration-resistant prostate cancer (CRPC) that cannot be cured with current therapies. Intratumoral androgen biosynthesis has been identified as one of the mechanisms leading to castration resistance. Recent studies have confirmed that prostate tumors can synthesize androgens by themselves to maintain tumor growth in androgen-deprived conditions. Thus, suppressing intratumoral androgen biosynthesis has become an attractive option for drug development. To understand the mechanisms of intratumoral androgen biosynthesis and develop new CRPC therapies, better preclinical models for CRPC are needed. In this study, we developed an orthotopic VCaP xenograft model suitable for studying the progression of CRPC and the mechanisms of intratumoral androgen biosynthesis in vivo. The VCaP model exhibited the clinical features of CRPC, including the activation of intratumoral androgen biosynthesis and the overexpression of androgen receptor (AR) and its splice variants. Furthermore, novel antiandrogens enzalutamide and ARN-509 reduced intratumoral androgen levels and altered steroidogenic enzyme expression in the VCaP model. In addition to preclinical studies, androgen levels were analyzed in prostate and serum specimens obtained from prostate cancer patients. Intraprostatic androgen levels in cancerous and benign samples were highly variable between the patients. Distinct intratumoral androgen levels and altered AR target gene expression were associated with TMPRSS2-ERG fusion gene expression

Nuclear magnetism and superconductivity in rhodium

This thesis presents the results of experiments studying nuclear magnetism, superconductivity and their mutual interaction in rhodium at ultralow temperatures with high nuclear polarizations. The experiments were performed with a new cooling apparatus particularly designed for such measurements. The highest nuclear polarizations reached were p = 0.95 and the lowest achieved temperature of the nuclear spin system was below 100 pK. The measured susceptibility data showed a clear antiferromagnetic tendency of the nuclear spin system, but no indication of a magnetically ordered state was observed. Multiple spin flips, where a single photon flips several nuclei were observed. The double-spin-flip resonance was observed at positive and for the first time also at negative spin temperatures. The behavior of the resonance fitted the theoretical expectations very well and its frequency shift gives direct information of the mutual interactions between the nuclear spins. A possible trace of the triple-spin-flip peak was also detected. Because of the rare properties of rhodium, where the critical field of superconductivity is considerably lower than the local field of the nuclei, experiments could be performed with polarized nuclei also in the superconducting state of the electron system. The measurements could thus be extended to a completely new regime, where polarized nuclei are embedded in a coherent conduction electron system. The spin-lattice relaxation time was found to be always longer in the superconducting state as compared to the normal state. Additionally in the superconducting state the relaxation time displayed an unexpectedly strong polarization dependence.reviewe

Surrogate Reasoning:An Artefactual Approach

Scientific practice revolves around an amazing variety of constructed objects rendered by different representational tools and media. These objects enable inferences concerning the natural and social phenomena in which scientists are interested. Philosophical discussion has approached the epistemic uses of such artefacts in terms of surrogate reasoning. Although this discussion has been insightful, it has remained limited in scope in that it has tended to fuse surrogate reasoning with representation. Roughly put, models have been taken as representations, and model-based representation has been analyzed in terms of surrogate reasoning. Such an understanding of surrogate reasoning latches onto the representational relationship between a model and a target, with the model acting as a surrogate for some identifiable target system. Knuuttila argues for an alternative artefactual approach that widens the discussion of surrogate reasoning beyond representation and modelling by covering: various kinds of scientific constructs; the different analogical and other relations among such objects; the relations between such objects and the features of natural and social systems. She uses examples from synthetic biology and economics to exemplify the artefactual approach to surrogate reasoning. Tarja Knuuttila is Professor of Philosophy of Science at the University of Vienna. Previously she was Associate Professor at the University of South Carolina (USA). She holds Master’s degrees in Economics (Helsinki School of Economics) and in Social and Moral Philosophy (University of Helsinki), and a PhD in Theoretical Philosophy (University of Helsinki). She served as the Editor-in-Chief of Science &amp; Technology Studies (2007–10) and spent 2009–10 as Visiting Research Associate at the California Institute of Technology. Knuuttila’s research is focused on scientific representation and modelling. Her approach is comparative: she has studied modelling in neuroscience, economics, and ecology, as well as in both systems and synthetic biology. Knuuttila also utilizes empirical studies as part of her philosophical agenda. She has published in numerous collections and journals, including British Journal for the Philosophy of Science, Philosophy of Science, Erkenntnis, European Journal for Philosophy of Science, Synthese, Studies in History and Philosophy of Science, Studies in History and Philosophy of Biological and Biomedical Sciences, The Monist, and Science &amp; Technology Studies. Tarja Knuuttila, Surrogate Reasoning: An Artefactual Approach, lecture, ICI Berlin, 23 January 2023, video recording, mp4, 43:10 <https://doi.org/10.25620/e230123

Imagination extended and embedded : artifactual versus fictional accounts of models

This paper presents an artifactual approach to models that also addresses their fictional features. It discusses first the imaginary accounts of models and fiction that set model descriptions apart from imagined-objects, concentrating on the latter (e.g., Frigg in Synthese 172(2):251-268, 2010; Frigg and Nguyen in The Monist 99(3):225-242, 2016; Godfrey-Smith in Biol Philos 21(5):725-740, 2006; Philos Stud 143(1):101-116, 2009). While the imaginary approaches accommodate surrogative reasoning as an important characteristic of scientific modeling, they simultaneously raise difficult questions concerning how the imagined entities are related to actual representational tools, and coordinated among different scientists, and with real-world phenomena. The artifactual account focuses, in contrast, on the culturally established external representational tools that enable, embody, and extend scientific imagination and reasoning. While there are commonalities between models and fictions, it is argued that the focus should be on the fictional uses of models rather than considering models as fictions.Peer reviewe

L’effet de réel revisited: Barthes and the affective image

This article addresses Barthes’s development from a structuralist semiotician towards an affectively responding reader in terms of ‘postrational’ subjectivity. In light of his whole oeuvre, Barthes anticipates the understanding of emotion as an integral part of cognition presented in contemporary social neuroscience. To illustrate Barthes’s growing awareness of the importance of this epistemological move, the article starts from his textual ‘reality effect’ as a critical vehicle of realist representation. It then shifts to his attempt at conceptualising an affective reading which resists the universalising idea of one ideologically determined signified. Barthes’s progress towards embracing the actual reader’s embodied self-feeling is prompted by two conceptual milestones: the obtuse meaning found in cinematic stills, and the experience of punctum felt in photos. In light of his lectures in the Collège de France, Barthes substitutes the Husserlian disembodied method of introspection with the Chinese wu-wei as a reading practice. As a result, his Zen-Buddhist concentration on bodily feelings elicited by visual/verbal images becomes a method capable of creating a fruitful link between language and wordless cognition. Finally, the article proposes an idea of the ‘embodied reality effect’ by reading affectively two similar scenes interpreted by the early and late Barthes himself

Children – the future of the Karelian language? Case study in a Karelian village

This article deals with the knowledge of the Karelian language of school children living in a Karelian village. Karelian is an endangered language and it is said that it is a language of old people, that is why I was interested in children’s knowledge of Karelian. The aim is consider how the children self-estimate their ability to speak, understand, read or write Karelian. This study shows that Karelian children do somehow know their heritage language. But to become skilful Karelian speakers children need plenty of help and support from their parents, teachers and from the communit

Orchestrating Without Partiture

Crisis in and around Ukraine is becoming the first show-case in multilateral diplomacy, where Remotely Piloted Aircraft Systems (RPAS) and other technologies are deployed to produce information for the diplomatic processes of the Organization for Security and Cooperation in Europe (OSCE)and to public at the same time. This has taken place in a very rapid manner without time for descent planning and through learning by doing before and in the middle of the start and development of the crisis special monitoring mission based on the consensus of 57 member states. \ This paper approaches these multi-lateral diplomacy scenes by looking at the work done through two disciplines which “orchestrate”; Social Science and Information Systems. Abbot et al. orchestration theory application into OSCE and to its “Ukraine toolbox” needs more research, in which e.g. IS literature´s socio-technical modeling methods will be helpful in order to bridge recognized gaps from practice and literature. \ Information system researchers and developers are needed in more active roles as intermediaries to complement existing principal-agent e.g. OSCE-RPAS and other ICT vendor relationships. More theoretical and empirical research is needed to make the IGOs’ orchestration to meet what ICT can offer for future crisis diplomacy. \ Keywords: Inter-governmental Organizations (IGOs), orchestration theory, Remotely Piloted Aircraft System (RPAS), multilateral diplomacy, Organization for Security and Cooperation in Europe (OSCE), information system development, Ukraine Special Monitoring Mission (SMM)

Elintarvikemarkkinoiden tuontiriippuvuus

Ruokahuollon turvaamisella on Suomessa pitkät perinteet ja elintarvikealan tuontiriippuvuus on tärkeä tietää huoltovarmuuden vuoksi. Tässä tutkimuksessa päivitettiin elintarviketoimialojen tuonti-panosasteet ja elintarvikemarkkinoiden tuontiaste vuosille 2008–2012 kertaluonteisten tuotanto-panosten eli välituotteiden käytön näkökulmasta. Investointitavaroiden tuonnin vaikutus elintarvike-tuotannon tuontiasteisiin arvioitiin vuoden 2012 osalta. Lisäksi tutkimuksessa vertailtiin Suomen, Ruotsin ja Tanskan tuontiasteita. Elintarvikeala Ruotsissa ja Tanskassa poikkeaa suomalaisesta. Vertailu Ruotsin ja Tanskan kesken selventää, ovatko ne Suomen tavoin riippuvaisia tuonnista. Tutkimus on jatkoa vuonna 2012 päättyneelle Elintarviketuotannon ja elintarvikemarkkinoiden riippuvuus tuonnista -tutkimukselle. Elintarviketoimialojen tuontipanosaste selvitettiin tuontipanosten arvon osuutena tuotoksen arvosta. Aineisto oli Tilastokeskuksen kansantalouden tilinpidon panos-tuotosaineisto. Menetelmänä käytettiin panos-tuotosmenetelmän tuotosmallia, jonka avulla voidaan laskea tuotannon edellyttämä välitön ja välillinen tuonti. Analyysi vuosilta 2003–2012 osoittaa, että panostuonnin lisäksi valmiselintarvikkeet huomioon ottava elintarvikemarkkinoiden tuontiaste on kasvanut 0,7 prosenttiyksikön vuosivauhdilla. Valmiselintarviketuonnin kasvua selittää määrän kasvu, sen sijaan tuontipanoksissa ovat hinnat nousseet tuontimääriä nopeammin. Panostuonti ja valmiselintarviketuonti ovat kasvaneet lähes samaan tahtiin. Elintarvikemarkkinoiden kokonaistuonnista valtaosa on tuontipanoksia. Vuonna 2012 elintarviketoimialojen investoinnit olivat 2 080 milj. euroa, joista tuontia arvioitiin olevan 825 milj. euroa eli 40 prosenttia. Muiden tuotantopanosten tuonti oli 5 380 milj. euroa ja valmiselintarviketuonti 2 495 milj. euroa. Elintarvikemarkkinoiden tuonti yhteensä oli 8 700 milj. euroa. Investoinnit mukaan lukien elintarvikemarkkinoiden tuontiaste on 28 prosenttia. Elintarviketuotannon ja jakelun tärkein tuontituoteryhmä on kemikaalit ja kemialliset tuotteet. Näistä suuri osa on maatalouteen tuotavia kasvinsuojeluaineita ja lannoitteita, mutta myös kaikilla aloilla käytettäviä puhdistus- ja desinfiointikemikaaleja. Maataloustuotteiden tuontia ovat puutarha-talouden, nurmi- ja öljykasvien sekä sokerijuurikkaan siemenet. Viljoista ruista tuodaan jauhojen raaka-aineeksi. Alkutuotannon tuotteita tuodaan raakakahvina, hedelminä, marjoina ja vihanneksina elintarviketeollisuuteen raaka-aineiksi. Elintarviketeollisuudessa maataloustuotteita tärkeämpiä tuontituotteita ovat elintarviketeollisuuden puolivalmisteet esimerkiksi soijavalkuainen ja eri rehuaineet. Elintarviketuotannon ja -jakelun sujumiseksi energiaa tuodaan raakaöljynä, kivihiilenä ja maa-kaasuna sekä erilaisina öljyjalosteina. Liikkeenjohdon palvelut sekä mainos- ja markkinatutkimuspalvelut ovat tärkeitä tuontituote-ryhmiä. Kotimainen elintarviketuotanto ja -kauppa ovat kansainvälisiä. Valmiselintarvikkeita ja tuotantopanoksia tuodaan, elintarvikkeita viedään ja jalostus- ja kaupan alan yritykset toimivat ulkomailla. Toisaalta tuloksiin tule suhtautua varauksella palvelualojen tuonnin tilastoinnin ja panos-tuotostaulukoihin kohdistamisen vaikeuksien vuoksi. Välillinen tuonti eli kotimaan muiden alojen tuonti elintarviketuotantoa ja -jakelua varten tarkoittaa, että elintarvikeala on riippuvainen muusta kotimaan tuotannosta. Mahdollisten tuontihäiriöiden lisäksi tuonti vaikuttaa muillakin tavoin. Keskeisten tuontipanosten kuten energian ja soijan hintaheilahtelut vaikuttavat tuotannon kannattavuuteen. Valmiselintarvikkeiden tuonnin kasvu lisää kilpailua kotimaassa. Tuotannon ylläpitämiseksi on kehitettävä uusia tuotteita ja lisämarkkinoita on haettava viennistä. Suomi on Ruotsia ja Tanskaa vähemmän riippuvainen tuonnista. Väkirikkaimman Ruotsin elintarvikemarkkina on suurin, eikä sen oma tuotanto riitä kattamaan kysyntää. Tanskan maaperä soveltuu viljelyyn ja se on vahvasti erikoistunut elintarvikevientiin. Sianlihan tuotanto vaatii kuitenkin tuontisoijaa. Ruotsissa ja Tanskassa sekä tuontipanosten osuus elintarviketuotannossa että valmiselintarviketuonnin osuus elintarvikemarkkinoilla ovat suuremmat kuin Suomessa. Tärkeimmät tuontipanokset ovat pääasiassa samoja, vaikka erojakin on. Kemikaalit on Suomen tavoin tärkein maatalouden tuontituoteryhmä Ruotsissa ja toiseksi suurin Tanskassa. Rehuraaka-aineet ovat Tanskassa maatalouden tärkein tuontipanos ja tärkeitä ne ovat myös muissa. Öljyjalosteet ovat Suomen lailla tärkeä tuontituoteryhmä Ruotsissa ja Tanskassa. Energian raaka-aineiden tuonti sen sijaan eivät ole yhtä tärkeä Tanskassa kuin muissa maissa. Elintarviketeollisuuden tärkein tuontituoteryhmä kaikissa maissa on oman alan jalosteet eli elintarviketeollisuuden tuotteet. Tutkimuksen analyysi elintarviketuotannon panostuonnista edellyttää yksityiskohtaista aineistoa. Tehty vertailututkimus tuo uutta tietoa kohdemaiden elintarviketuotannon ja -markkinoiden tuonti-riippuvuuksista ja rakenteista. Seikkaperäisempi vertailu edellyttäisi perusteellista syventymistä kohdemaiden tilastojen laadintaan.201