Väitöskirjat

Recent Submissions

  • Wahlström, Max (Helsingin yliopiston nykykielten laitos, 2015)
    Case inflection, which is characteristic of Slavic languages, was lost in Bulgarian and Macedonian between approximately the 11th and 16th centuries. My doctoral dissertation examines the process of this linguistic change and sets out to find its causes and evaluate its consequences. In the earlier research literature, the case loss has been attributed either to language contacts or to language-internal developments such as sound changes, yet none of the theories based on a single explanatory factor has proven satisfactory. In this study, I argue that previous researchers into Late Medieval manuscripts often tried to date the language changes earlier than is plausible in light of the textual evidence. I also propose that the high number of second-language speakers is among the key factors reducing the number of morphological categories in a language; meanwhile, several minor developments related to the case loss for instance, in the marking of possession are likely to have resulted from a specific contact mechanism known as the Balkan linguistic area. My main methodological claim is that the study of language contacts must take into account a general typological perspective. Furthermore, quantitative typological methods are also helpful in assessing whether the shared linguistic features within a linguistic area emerged independently of each other. This dissertation is divided into three parts, each representing a different methodological approach. Through corpus methods, among other approaches, the first part examines the process of the loss of case inflection within the manuscript tradition stemming from Old Church Slavonic. The second approach is based on the study of language contacts. I compare the development of the Bulgarian and Macedonian case systems with the Albanian, Balkan Romance, and Greek case systems and their evolution. In addition, using the Romani language as an example, I analyze the effect of the sociolinguistic setting on the type of contact-induced language change. The third approach examines the case systems of Bulgarian and Macedonian and the rest of the Balkan linguistic area in a cross-linguistic connection to evaluate the extent to which the phenomena related to the case loss can be attributed to universal tendencies observed in the languages of the world.
  • Santala, Susanna (Helsingin yliopisto, 2015)
    In this historiographical study I evaluate the placement of Eero Saarinen s airport terminals in the history of modern architecture. His Trans World Airlines Terminal (1956-62) and Dulles International Airport (1958-63) were the first airport terminals to enter the annals of modern architecture. I hypothesize that the airport terminal was previously excluded as a building type from historiography since it was seen as infrastructure, not architecture. Furthermore, its modernity did not coincide with the aims of historians, who could not utilize an emergent building type to demonstrate how modernism revolutionized architectural vocabularies. Discussing the related histories of aviation and technologies, the typological instability of the airport terminal, and Saarinen s architectural practice, I utilize genealogy, microhistory, and Science and Technology Studies to intervene in the historiography of modern architecture. Specifically, I question the assumption that architecture follows technological developments, the narrow interpretation of modernity dominating the writing of architectural history, and the resulting myopia in the classification of emerging building types. I view Saarinen s architectural practice as one of the many laboratories for a new architecture. Mapping such laboratories reveals a multifaceted view of postwar architecture, where modernism is explained by individual actors laboring at their localized sites to mediate a particular kind of modernity. I argue that Saarinen s engagement with technology and his laboratory-like working methods reconciled the contradictions between modern architecture and its blind spot, the airport terminal. This synthesis allowed the terminal building to transcend its utilitarian-technological nature as transportation infrastructure and led to its inclusion in the history of modern architecture as a building type that has its own history and parameters for design. This study makes three contributions. It outlines the history of the airport terminal emphasizing buildings that could have easily found their place in the canon of modern architecture. It explains the reasons for their exclusion and suggests ways to reduce the canon s myopia towards variants of modernism. More broadly, this study contributes to our understanding of the historiography of modern architecture and its logic of including emergent buildings by acknowledging the airport terminal as an emblematic building type of the twentieth century.
  • Moustgaard, Heta (Helsingin yliopisto, 2015)
    Depression is a leading cause of disability worldwide. At worst, it may lead to frequent hospitalisation and even premature death. The risk of suicide is particularly high among the depressed. This study assessed whether social and economic resources protect depressed patients from psychiatric hospital admission and premature mortality. The study also aimed to establish the role of alcohol and the rapidly increased antidepressant treatment of depression in these outcomes. The study used large, longitudinal register samples of the Finnish adult population, combining information from various administrative registers. Depression was assessed from psychiatric hospital care and antidepressant purchases. Treatment and depression outcomes were assessed in 1-10-year follow-ups. The results indicate that at least in a population already in contact with the healthcare system, antidepressant treatment and depression outcomes vary only modestly according to social factors. However, material aspects of socioeconomic position such as a low income, not owning a home and being unemployed increased the risk of hospital admission for depression by 20-40 per cent among those with previous depression treatment, even after controlling for baseline depression severity and psychiatric comorbidity, whereas education and occupational social class were unrelated to admission risk. Having no partner and living without co-resident children also increased the admission risk. None of the social factors studied buffered against excess mortality among the depressed. Educational differences in the prevalence of antidepressant use before and after hospital care for depression were small and mostly limited to the period after discharge. Antidepressant use immediately after discharge was slightly less common among those with a low level of education, but educational differences increased thereafter as antidepressant use decreased more rapidly among this group. Differences in daily antidepressant use that met treatment guidelines were more pronounced than those for any antidepressant use, suggesting a need for improving treatment adequacy and adherence particularly among patients with a low level of education. The study established the central role of excessive alcohol consumption as a pathway to depression mortality. Alcohol-related causes accounted for about half of the excess mortality of depressed men and around a third of depressed women. Improving the detection and management of substance use problems would thus be critical for reducing depression mortality. Increased antidepressant sales do not seem to have prevented female suicides. However, among men an increase in the proportion of antidepressant users receiving minimally adequate treatment reduced non-alcohol-related suicides. The results suggest that increased adequacy of antidepressant treatment has been more central in reducing suicide rates than the mere increase in per-capita antidepressant sales or prevalence of antidepressant use.
  • Henriksson, Laura (Suomen Musiikkitieteellinen Seura, 2015)
    Summary Vocal humour and critique in the couplet recordings by J. Alfred Tanner, Matti Jurva, Reino Helismaa, Juha Vainio and Veikko Lavi The aim of this study is to research the lyrics and singing styles of five Finnish couplet singers who are connected to the Finnish schlager tradition. The material-oriented study is performed by analyzing altogether 160 couplet recordings sung by J. Alfred Tanner, Matti Jurva, Reino Helismaa, Juha Vainio, and Veikko Lavi. The study examines the singers humoristic and critical approaches to the lyrics and investigates how the attitudes are performed orally by the singers. The aim of the study is to analyze the singing styles of the songs together with the content of the songs lyrics. The history of the couplet and the previous studies of the subject are reviewed in the beginning of the first part of the work, which also contains the methodological background of the work, which is divided into cultural models and attitudes and to textual and musical conventions. The methodological section introduces a viewpoint which takes into account the couplet songs musical and textual practices alongside with the general cultural views such as attitudes advocating the culture of contestation and hegemonic masculinity. A detailed analysis of Juha Vainio s couplet song Käyn ahon laitaa demonstrates in practice how the couplet recordings can be analyzed. In the articles the couplets themes are examined by using scientific concepts and by analysing couplet recordings. In the first article couplets and their critical attitudes towards persons in power are examined by using the term of carnivalism. The second article deals with self-irony of the couplets characters which is investigated by using the concept of incongruity and the relief theory previously used in humour studies. The subject of the third article is female characters in the couplet songs. The subjects of the fourth article are masculinity and its vocal interpretation in the songs. The theoretical framework of the study is based on the Judith Butler s concept of performativity and Zygmunt Bauman s categories of the postmodern pilgrim and its followers. Keywords: Couplet, humour, carnivalism, culture of contestation, performativity
  • Song, Xin (Helsingin yliopisto, 2015)
    Background and aims: Obesity has become the sixth most important risk factor contributing to the overall burden of a variety of diseases worldwide. The association of anthropometric measures of obesity with mortality from various causes and incidence of cancers of various sites has been investigated, but it remains controversial. The aims of this study were to: 1) evaluate the epidemiological nature of the association of anthropometric measures of obesity with mortality from various causes, and to detect a potential threshold in this association; 2) study the epidemiological nature of the association between body mass index and incidence of cancer of different sites, and to detect a potential threshold in the association; 3) compare the strengths of different anthropometric measures of obesity in relation to cardiovascular disease (CVD) mortality; 4) assess the risk of CVD mortality in relation to obesity and sex in the general population, and also separately for those with or without diabetes at baseline. Study population and Methods: This study was based on data subsets of the Diabetes Epidemiology: Collaborative analysis Of Diagnostic criteria in Europe (DECODE) study and the National FINRISK study, including 72 947 European men and 62 798 women (I), 26 636 Finnish men and 28 089 women (II), 24 686 European men and 21 965 women (III/IV), and 23 629 European men and 21 965 women (V) aged 24 years or above at baseline. Hazard ratios (HRs) corresponding to categorical or continuous body mass index (BMI), waist circumference (WC), waist-to-hip ratio (WHR), waist-to-height ratio (WHtR) or waist-to-stature ratio (WSR), a body shape index (ABSI) and waist-to-hip-to-height ratio (WHHR) were estimated by the Cox proportional hazards model adjusting for several potential confounding factors measured at baseline. The non-parametric smooth functions of several anthropometric measures of obesity were fitted to health outcomes in order to explore the potential curvilinear relationship using the spline regression model, with a threshold detected by a piecewise regression model (II/III). HR per standard deviation increment of each anthropometric measure of obesity in relation to CVD mortality was compared using the paired homogeneity test (IV). Results: BMI, WC and WHtR had a U- or J-shaped relationship with all-cause mortality (I/III), whereas WHR, ABSI and WHHR had a linear positive relationship with all-cause mortality (III). BMI had a J-shaped relationship with CVD mortality (I/III), whereas anthropometric measures of abdominal obesity (WC, WHR, WHtR and ABSI) had a linear positive relationship with CVD mortality (III). BMI had a U-shaped relationship with cancer mortality in both men and women but disappeared among non-smokers, which showed no association (I). BMI had a linear positive association with incidence of cancers of the colon, liver, kidney, bladder and all sites combined in men, and of cancers of the stomach, colon, gallbladder and ovary in women, an inverse association with incidence of cancers of the lung in men and the lung and breast in women, and a J-shaped association with incidence of all cancers combined in women (II). A one-standard-deviation increase in all obesity indicators were significantly associated with a more than 19% increase of CVD mortality risk in both men and women, and the prediction for CVD mortality was stronger with anthropometric measures of abdominal obesity than that with BMI and ABSI, and most strongly with the WHtR/WSR (IV). Men had higher CVD mortality rates and higher HRs across BMI categories, and categories of abdominal obesity than women (V). The sex difference in CVD mortality was slightly smaller in obese than in non-obese individuals; the negative interactions were statistically significant between sex and WC (p =0.02), and sex and WHtR (p =0.01). None of the interaction terms was significant when the analyses were carried out among non-diabetic or diabetic individuals separately (V). Conclusions: This study confirmed the deleterious effect of obesity on mortality from various causes and incidence of cancers of certain sites. The prediction for CVD mortality with anthropometric measures of abdominal obesity was stronger than that with BMI, which may imply a more important role of fat distribution than fat accumulation and suggest that an effective obesity prevention strategy should emphasize the importance of abdominal obesity. Men had higher CVD mortality than women across all categories of anthropometric measures of obesity, which further supports the view of higher intra-abdominal fat accumulation in men than in women, even in non-obese individuals. Obesity seems slightly to diminish the female advantage in CVD mortality, irrespective of diabetes status. This may indicate that women may gradually lose their cardiovascular advantage when they are obese, probably due to a more pronounced clustering of CVD risk factors among obese women.
  • Aaltonen, Kalle (Helsingin yliopisto, 2015)
    Rheumatoid Arthritis (RA) is an autoimmune disease, which is treated with anti-inflammatory and immunosuppressive medication comprising synthetic disease-modifying anti-rheumatic (sDMARDs) and biologic drugs. In this thesis all published randomized controlled trials studying the efficacy and safety of biologic drugs based on the inhibition of tumor necrosis factor (TNF) were identified, evaluated and pooled in using a systematic review including a meta-analysis. Then we pursued a cross-sectional overview on disease activity and medical treatment of patients with RA treated wthin the Finnish specialized healthcare. Finally, we executed two cohort studies in which we combined longitudinal patient data with information on the incidence of serious infections, malignancies and joint replacement operations retrieved from national registers. Forty-one articles reporting on 26 RCTs of TNF-inhibitors were included in the systematic review and meta-analysis. TNF-inhibitors as a monotherapy were more efficacious than placebo but comparable to methotrexate (MTX). TNF-inhibitor and MTX combination was superior to either MTX or TNF-inhibitor alone. TNF-inhibitors were relatively safe as compared to either MTX or placebo. The cross-sectional study revealed 91%, 58% and 21% of patients as concurrent users of (sDMARDs), glucocorticoids and biologics, respectively. The cohort studies showed that the adjusted incidence rate ratios (aIRRs) of infections compared to sDMARD users were 0.9 (95% CI 0.6-1.4) and 1.1 (95% CI 0.59-1.9) for the users of TNF-inhibitors and rituximab, respectively. The aIRRs of malignancies were similar between the sDMARD and biologics users. There were more primary joint replacement operations per 100 patient years among the users of biologic drugs (3.89, 95% CI 3.41 4.41) vs. DMARD (2.63, 2.35 2.94) users but slightly fewer revisions (0.65, 0.46 0.88 vs. 0.83, 0.68 1.01). Efficacy and safety of TNF-inhibitors are comparable to MTX and only few differences were observed between individual agents. Currently, more than 20% of Finnish RA patients are using biologic drugs, with a majority of them in combination therapy with sDMARDs. The incidence of serious infections and malignancies is comparable between the users of sDMARDs, TNF-inhibitors and rituximab. Compared to sDMARD users, biologic drugs users had a higher incidence of joint replacement operations while the durability of the prostheses were similar.
  • Juuri, Juuso (Helsingin yliopisto, 2015)
    Kainate-type of ionotropic glutamate (KA) receptors are associated with the modulation of neuronal excitability, synaptic transmission, and activity of neuronal networks. They are believed to have an important role in the development of neuronal connections. In this thesis, the role of KA receptors in the early brain development was assessed by conducting in vitro electrophysiological recordings from individual neurons at CA3 region in acute slices of neonatal rodent hippocampi. It was found that activation of separate KA receptor populations promoted action potential firing in both glutamatergic pyramidal neurons and GABAergic interneurons. The receptors in pyramidal neurons displayed a high affinity for agonist kainate, appeared to lack subunit GluK1, and promoted spontaneous firing of pyramidal neurons without depolarizing them. The receptors in interneurons contained subunit GluK1 and their activation suppressed afterhyperpolarizing current of medium duration (ImAHP). Receptors in both neuron types appeared to be activated tonically by ambient glutamate, suggesting that their physiological role may be to act as a modulatory mechanism sensitive to changes in extracellular glutamate concentration. Changes in activity of neurons at CA3 by activation of KA receptors were reflected on the network level. Promotion of pyramidal cell firing by pharmacological activation of high-affinity KA receptors lead to enhanced glutamatergic drive and generation of network bursts in the CA3 region. The ImAHP in interneurons was also suppressed by apamin, a blocker of SK potassium channels that mediate majority of this current, and apamin enhanced generation of network bursts. This suggests that also KA receptor mediated regulation of ImAHP may modulate network activity. It was also found that there was an interaction between KA receptors and ethanol in the modulation of hippocampal network: ethanol decreased the occurrence of the network bursts at postnatal days 1 (P1) and P10, whereas it increased bursting at P5. The network effects of ethanol were partially or completely counteracted by specific pharmacological block of GluK1 subunit-containing KA receptors. The findings disclose that via regulation of activity of individual neurons, KA receptors are capable of robust modulation of network activity in immature hippocampus. Additionally, exogenous agents affecting KA receptors may perturb activity dependent developmental processes that are central for the synaptic development. The results shed light on the mechanisms underlying development of hippocampal connectivity, and may help to understand early pathologies of the brain that have developmental origins.
  • Mogensen, Ditte (Helsingin yliopisto, 2015)
    Forests emit biogenic volatile organic compounds (BVOCs) that, together with e.g. sulfuric acid, can operate as aerosol precursor compounds when oxidised. Aerosol particles affect both air visibility, human health and the Earth s radiative budget, thus making the emission inputs and oxidation mechanisms of VOCs absolutely crucial to understand. This thesis discusses the life cycle of compounds in the atmosphere. Specifically, we studied the representations of emission of BVOCs, the atmosphere s oxidation ability along with the sources and sinks of sulfuric acid. The main tool to achieve this was numerical modelling, often compared to field observations. Additionally, we performed computational chemistry simulations in order to calculate transitions in sulfuric acid. The main findings of this thesis can be summarised into the following: (1) Biological understanding of VOC emission processes needs to be enhanced in order to predict VOC concentrations with a high precision. (2) The unexplained fraction of the total OH reactivity in the boreal forest is larger than the known fraction and known secondary organic oxidation products of primary emitted terpenes cannot explain the missing reactivity. (3) OH is the main oxidation agent of organic compounds in the boreal atmosphere. (4) Criegee Intermediates, produced from unsaturated hydrocarbons, can oxidise SO2 effectively in order to provide as an essential source of sulfuric acid in areas with high VOC concentrations. (5) Two-photon electronic excitation did not turn out to be a significant sink of gaseous sulfuric acid in the stratosphere. This thesis closes a large part of the sulfuric acid concentration gap in VOC rich environments. Further, this thesis raises awareness of the fact that we still do not fully comprehend the mechanisms leading to BVOC emissions nor the organic atmospheric chemistry in the boreal forest. Finally, this work encourage to study alternative BVOC emission sources as well as alternative atmospheric oxidants.
  • Saad, Elyana (Helsingin yliopisto, 2015)
    The relationship between mental representations based on external visual percepts (i.e., information held in short-term memory or via mental imagery) and the encoding of visual input remains unsettled. What stimulates this debate is the share of overlapping neural resources between visual short-term memory (VSTM), mental imagery and visual perception in the realm of the early visual cortex (EVC). This overlap raises a number of questions: how do the internal memory and imagery representations affect the perception of incoming visual information? What happens to imagery and VSTM abilities when cognitive resources need to be shared with the encoding of visual input? In short: how do visual memory/imagery and visual perception interact? This work addressed these questions by the use of behavioral paradigms coupled with transcranial magnetic stimulation (TMS) in situations where the encoding of the visual percept (measured via the tilt after effect (TAE) magnitude) happens either simultaneously or subsequently to holding information in VSTM/imagery. Therefore, when VSTM and the encoding of external input occurred concurrently, VSTM maintenance was found to inhibit visual encoding, reflected as a reduction of the TAE. Using TMS, it was shown that this inhibition takes place at the level of EVC. This reduction was found when the VSTM content matched the visual input, and when they were incongruent. However, when the encoding of external input occurred after VSTM maintenance phase had ended, VSTM maintenance was found to facilitate the former when the VSTM content matched the visual input. The subjective strength and the contrast of VSTM and mental imagery content (as reported by participants) affect visual detection of a briefly presented masked target. The reported visual contrast was positively associated with reporting target presence for both VSTM and mental imagery, in other words, inducing a more liberal bias. However, a differential effect was found for the subjective strength of the representations. Whereas the subjective VSTM strength was positively associated with the visual detection of the target, the opposite effect was observed for imagery. Finally, TMS applied at the EVC revealed a partial dissociation in the neural basis of VSTM and mental imagery by inducing delayed responses for the former selectively. Thus, while VSTM and mental imagery share neural resources, their neural mechanisms are partly dissociable at the level of early visual cortex.
  • Kaprio, Tuomas (Helsingin yliopisto, 2015)
    Background and aims Colorectal cancer (CRC) is one of the world s three most common cancers, and its incidence is rising. Novel biomarkers are essential for diagnostic and prognostic tools and to identify patients for targeted and individualized therapy. Covering all human cells, the carbohydrate units of glycoproteins, glycolipids, and proteoglycans are glycans. Carcinoma-related glycan structures are potential cancer biomarkers, since glycosylation evolves during carcinogenesis. Suggested to play a role in carcinogenesis are glycoproteins podocalyxin (PODXL) and regenerating islet-derived gene (REG) 4. PODXL s aberrant expression or allelic variation or both associate in different cancers with poor prognosis and unfavourable clinicopathological characteristics. Up-regulated REG4 expression occurs in inflammatory bowel diseases and also in gastrointestinal cancers. Reports on the association of REG4 expression with CRC prognosis have been mixed, however. Material and Methods Comparison of the N-glycan profiles of 5 rectal adenomas and 18 rectal carcinomas of different stages was by matrix-assisted laser desorption-ionization time-of-flight mass spectrometry. Tumour expression of REG4 and PODXL was evaluated by immunohistochemistry in 840 consecutive CRC patients surgically treated between 1983 and 2001. In addition we evaluated in a subgroup of 220 consecutively surgically treated CRC patients the tumour expression of MUC1, MUC2, MUC5AC, synapthophysin, chromogranin, sialyl Lewis a (sLea), and pauci-mannose. All patients were treated at Helsinki University Hospital (HUH). Results Rectal adenomas and carcinomas can be distinguished from one another based on their N-glycosylation profile. Differences in N-glycosylation existed also between carcinomas of different stages. Based on these results pauci-mannose and sLea were chosen for immunohistochemical analysis: in CRC sLea correlated with poor prognosis, and in advanced CRC, pauci-mannose expression correlated with poor prognosis. PODXL was an independent marker of poor prognosis in CRC. The two antibodies showed similar prognostic profiles, but their staining patterns differed, and they recognized different groups of patients with a poor prognosis. Combination of the two PODXL antibodies identified a group of patients with even worse prognosis. REG4 expression associated with MUC1, MUC2, and MUC5AC expression in CRC and was a marker of favourable prognosis in non-mucinous CRC. Conclusion Mass spectrometry identified several carcinoma-related glycans and a method of transforming these results into immunohistochemistry was demonstrated. PODXL was a marker of poor prognosis in CRC, whereas REG4 expression predicted a favourable prognosis in non-mucinous CRC.
  • Sand, Andrea (Helsingin yliopisto, 2015)
    In the face of the world's increasing demand for energy, and the need to find sustainable and environmentally friendly ways of producing that energy, fusion power offers an attractive possibility. However, the harsh operating conditions of future fusion devices poses a significant challenge for materials development and engineering. Tungsten (W) and tungsten alloys are current candidate materials for both structural and plasma-facing components, due to favourable properties such as good thermal conductivity, high heat strength and stability, and resistance to erosion. However, fusion reactor components will be subjected to high neutron loads, and little is currently known of the effects of radiation on the mechanical properties of this intrinsically brittle metal. The extreme conditions in a future fusion reactor cannot be reproduced in existing experimental facilities, rendering simulation an invaluable tool in understanding the radiation damage processes. Multiscale methods are necessary to span the length and time scales involved, from the picosecond and nanometer scale of displacement cascades giving rise to the primary damage, to the evolution of the radiation induced microstructure over the seconds of typical in-situ ion irradiation experiments, and further to the years of a reactor component s life time. In order to implement a multiscale simulation method, information must be distilled and transferred from the smaller scale to the larger. Molecular dynamics (MD) simulations are ideal for studying the primary damage, but individual cascades vary greatly, and simulating high energy impacts in MD requires immense computer capacity. It is therefore not possible to simulate directly the whole variety of cascade outcomes. General laws deduced from the MD data can, however, be used to statistically generate varying cascades in the thousands. In this thesis we use MD simulations to study the primary damage in metals, with focus on tungsten. We identify aspects of the simulation methodology which affect the results, and validate our methods by direct comparison to experiments. Detailed analysis of the primary damage from high-energy cascades shows the formation of novel defects, confirming recent experimental observations. We also show that defect cluster sizes follow a general scaling law, which can be used to statistically generate cascade debris as input for microstructural evolution models, circumventing the need to directly simulate thousands of cascades.
  • Hämäläinen, Saara (Helsingin yliopisto, 2015)
    Our thesis has three individual papers and an introduction. It contributes to dynamic price and search theory. The first paper deals with the classic problem of trading under asymmetric information. The other two analyze retailing strategies that help lock in buyers by creating in-store frictions. In the first paper, we investigate welfare and equilibrium trading in a decentralized search market with asymmetric information and bilateral communication opportunities. Sellers and buyers meet randomly and pairwise and view a shared signal of the seller's quality. In the following signaling game, the sellers can either rely on this costless signal (pool) or costly signaling (separate). We observe that, although the average market quality is high, additional information is not generally welfare improving. All equilibria are inefficient. Contrary to the usual tradeoff between price and liquidity, we find that the signals can help sustaining stationary Markovian equilibria where higher quality is traded faster. In the second paper, we construct a novel search model that features in-store frictions and equilibrium price dispersion both within and across stores. The frictions originate from the gradual arrival of price information within stores and the existence of deadlines for buyers. We show that sellers have an incentive carry several similar items and generate price variation among these items to amplify the existing search frictions and create barriers to switching in an environment where none exist initially. It also helps them to discriminate better between buyers, who end with diverse degrees of price information. As the number of items in stock expands, sellers can extract more profits. In our third paper, we develop a price search model that features endogenous frictions in a duopolistic environment. These frictions originate from the gradual arrival or price information within stores and the existence of deadlines for buyers. We show that both sellers have a strategic incentive to generate frictions. There exists exactly two equilibria with a unique asymmetric pattern: a prominent seller, whose expected price is higher but the in-store frictions lower, and a non-prominent seller. The buyers are divided exactly equally into informed and uninformed consumers, and into those who fail to find anything. Under the Poisson process, this surplus loss is about 6 %.
  • Helmiö, Päivi (Helsingin yliopisto, 2015)
    TOWARDS BETTER PATIENT SAFETY: The WHO Surgical Checklist in Otorhinolaryngology More than one-half of adverse events in health care are related to surgery. Surgical patient injuries account for about 80% of patient injuries in otorhinolaryngology (ORL). The World Health Organisation (WHO) has developed a Surgical Safety Checklist to prevent errors in the operating theatre. Its use has been shown to reduce complications and mortality. The aims of the present study were to identify errors that may underlie those patient injuries that occur in operative ORL, to assess the effects of the WHO checklist on working processes in the operating theatre, including compliance, and to evaluate how it would fit into the specialty. Data of the patient injuries that were sustained during treatment by the ORL specialty between the years 2001 and 2011 were obtained from a search of the Finnish Patient Insurance Centre registry. The causes of the injuries were analysed, and whether the WHO checklist could have prevented the error was evaluated. The checklist was implemented in four Finnish hospitals as a pilot in 2009. A prospective before-versus-after-intervention study was conducted with a questionnaire for OT personnel in these four hospitals to evaluate the checklist. The checklist was subsequently implemented for regular use in the operative unit of the Department of Otorhinolaryngology of Helsinki University Central Hospital. After one-year of use, compliance and user attitudes were analysed by using data obtained from the operations database and a survey of operative ORL personnel. In the 10-year study period, 188 patient injuries were associated with operative ORL. A total of 142 (75.5%) of these injuries occurred due to errors that were made in the operating theatre, and in 125 cases (66.5%) a manual error in performing the surgery was the primary cause of the injury. Six injuries (3.2%) were caused by wrong site surgery. An error had some degree correspondence with a WHO checklist item for 18 injuries (9.6%) and it was determined that 9 of these injuries (4.8%) could have been prevented had the checklist been correctly used. The implementation of the checklist enhanced the communication between the surgical team members, improved verification of the patient s identity and of the correct operation site. Checklist compliance was 62.3% during first year of use. It was considered easy to use and the Safety Attitude Scores of the personnel were found to be on a high level. All check items on the list were considered important for ORL. However, a more compact checklist for outpatient surgery was requested. Patient injuries in ORL were strongly related to surgery. The WHO Surgical Safety Checklist seems to be a beneficial tool for preventing errors ORL and is highly relevant for the specialty.
  • Turunen, Harri (Helsingin yliopisto, 2015)
    I study the importance of variation in the higher moments of macroeconomic and financial quantities. The first essay considers the effects of uncertainty on the fiscal multiplier when the economy has hit the zero lower bound (ZLB) on the nominal rate in a relatively standard New Keynesian Dynamic Stochastic General Equilibrium (DSGE) model. As the ZLB is a very strong form of nonlinearity, the model is solved using a numerical method. Uncertainty in government spending and productivity are modeled as stochastic volatility. Confirming previous research (e.g. Christiano, Eichenbaum and Rebelo, 2011), the multiplier is found to be higher when at the bound, and the effects of volatility shocks are found to be noticeable (e.g. Basu and Bundick, 2015). Uncertainty is found to have an impact on the multiplier: when future spending is uncertain, the multiplier is high, but when future productivity is uncertain, the multiplier is low. The second essay studies whether or not DSGEs are able to generate simulated realizations with realistic third and fourth moments. Many time series in macroeconomics and finance exhibit either excess kurtosis or skewness or both. However, as was shown by Ascari et al (2013), standard DSGEs such as the neoclassical growth model or the model of Smets and Wouters (2007) are unable to produce realizations with reasonable moments, regardless of shock distribution or the order of the Taylor approximation applied. My results however indicate that this is mostly due to lack of nonlinearity in the models, since especially a model with a very strong form of nonlinearity, such as the ZLB, is able to generate non-Gaussian realizations. The third essay considers the pricing of macroeconomic risk. The theory of Merton (1973) implies that there can be other sources of priced risk than the risk associated with the return on the market portfolio and that an appropriate measure for sensitivity of a stock to this risk is the covariance of the return of that stock with the source of that risk. I apply the multivariate volatility model of Engle (2002) to estimate time-varying covariances of US stock portfolios with a variety of US macro time series. The finding is that inflation and unemployment are priced in the market and earn a negative premium, while the growth rate of industrial production and the Case-Shiller house price index are not priced.
  • Stewart, Timo (Helsingin yliopisto, 2015)
    This study analyses Finnish Christian Zionism from the end of the 19th century to the 1960s using the methodology of the history of ideas. It evaluates previous interpretations and investigates how Finns and in particular Finnish Christians related to Zionism and the State of Israel and why many Finnish Christians gave Zionism and the State of Israel a religious significance. The study points to three significant sources of growing Finnish Christian interest in Palestine, Jews and prophecy before Israeli independence. The first was through early visits to Palestine and the travel accounts that ensued. Pastors and theologians were particularly active in seeking out the lands of the Bible and the Fifth Gospel that they saw in it. The second was missionary work, which created a small but influential group of Finnish experts on Palestine. Of the people they encountered in Palestine, the missionaries clearly identified most with the Zionists and conveyed their worldview to their Finnish audiences. The third source was the increasingly prevalent prophecy literature that more frequently and confidently linked Zionism with the fulfilment of Biblical prophecies. This was most common amongst Pentecostals, but soon Lutheran missionaries and Evangelical revivalist followed suit. With the creation of the State of Israel even broadly read Lutheran papers made use of the same interpretive traditions. Interpretations varied in detail, but general allusions to an unspecified connection between Bible prophecy and the State of Israel founded in 1948 become common to the point of not requiring explanations. Even bolder forms of Christian Zionism were never challenged. These interpretations were facilitated until the middle of the 1960s by very favourable popular impressions of Zionism and Israel, in which the national experiences of Finland and Israel were seen to have much in common. In contrast, the voice of the Palestinians was not heard at all. Many Finnish Christians saw the State of Israel as a sign of the times and a miracle from year to year. Zionism and the State of Israel seemed to offer an answer to the question of God s continuing involvement with the world and the significance of the Bible. They were constantly relevant signs, but also seen as proof that settled the question of whether the Bible could be trusted. In the eyes of many Finnish Christians this gave the State of Israel a very special significance indeed.