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  • Laas, Karin (Helsingin yliopisto, 2009)
    Rheumatoid arthritis (RA) and other chronic inflammatory joint diseases already begin to affect patients health-related quality of life (HRQoL) in the earliest phases of these diseases. In treatment of inflammatory joint diseases, the last two decades have seen new strategies and treatment options introduced. Treatment is started at an earlier phase; combinations of disease-modifying anti-rheumatic drugs (DMARDs) and corticosteroids are used; and in refractory cases new drugs such as tumour necrosis factor (TNF) inhibitors or other biologicals can be started. In patients with new referrals to the Department of Rheumatology of the Helsinki University Central Hospital, we evaluated the 15D and the Stanford Health Assessment Questionnaire (HAQ) results at baseline and approximately 8 months after their first visit. Altogether the analysis included 295 patients with various rheumatic diseases. The mean baseline 15D score (0.822, SD 0.114) was significantly lower than for the age-matched general population (0.903, SD 0.098). Patients with osteoarthritis (OA) and spondyloarthropathies (SPA) reported the poorest HRQoL. In patients with RA and reactive arthritis (ReA) the HRQoL improved in a statistically significant manner during the 8-month follow-up. In addition, a clinically important change appeared in patients with systemic rheumatic diseases. HAQ score improved significantly in patients with RA, arthralgia and fibromyalgia, and ReA. In a study of 97 RA patients treated either with etanercept or adalimumab, we assessed their HRQoL with the RAND 36-Item Health Survey 1.0 (RAND-36) questionnaire. We also analysed changes in clinical parameters and the HAQ. With etanercept and adalimumab, the values of all domains in the RAND-36 questionnaire increased during the first 3 months. The efficacy of each in improving HRQoL was statistically significant, and the drug effects were comparable. Compared to Finnish age- and sex-matched general population values, the HRQoL of the RA patients was significantly lower at baseline and, despite the improvement, remained lower also at follow-up. Our RA patients had long-standing and severe disease that can explain the low HRQoL also at follow-up. In a pharmacoeconomic study of patients treated with infliximab we evaluated medical and work disability costs for patients with chronic inflammatory joint disease during one year before and one year after institution of infliximab treatment. Clinical and economic data for 96 patients with different arthritis diagnoses showed, in all patients, significantly improved clinical and laboratory variables. However, the medical costs increased significantly during the second period by 12 015 (95% confidence interval, 6 496 to 18 076). Only a minimal decrease in work disability costs occurred mean decrease 130 (-1 268 to 1 072). In a study involving a switch from infliximab to etanercept, we investigated the clinical outcome in 49 patients with RA. Reasons for switching were in 42% failure to respond by American College of Rheumatology (ACR) 50% criteria; in 12% adverse event; and in 46% non-medical reasons although the patients had responded to infliximab. The Disease Activity Score with 28 joints examined (DAS28) allowed us to measure patients disease activity and compare outcome between groups based on the reason for switching. In the patients in whom infliximab was switched to etanercept for nonmedical reasons, etanercept continued to suppress disease activity effectively, and 1-year drug survival for etanercept was 77% (95% CI, 62 to 97). In patients in the infliximab failure and adverse event groups, DAS28 values improved significantly during etanercept therapy. However, the 1-year drug survival of etanercept was only 43% (95% CI, 26 to 70) and 50% (95% CI, 33 to 100), respectively. Although the HRQoL of patients with inflammatory joint diseases is significantly lower than that of the general population, use of early and aggressive treatment strategies including TNF-inhibitors can improve patients HRQoL effectively. Further research is needed in finding new treatment strategies for those patients who fail to respond or lose their response to TNF-inhibitors.
  • Kaukua, Jarmo (Helsingin yliopisto, 2004)
  • Haapamäki, Johanna (Helsingin yliopisto, 2011)
    Health-related quality of life (HRQoL) measurement has become an important outcome in treatment trials and in health policy decisions. HRQoL can be measured by using generic or disease-specific tools. Generic instruments can be used for comparing health status among patients in different health states and conditions but they do not focus specifically on the issues relevant in a particular disease. Disease-specific tools may be more responsive to changes within a specific condition. In earlier studies, impairment of HRQoL has been evident in patients with inflammatory bowel disease (IBD), especially when the disease is active. Data about the impact of comorbidity or demographic characteristics of the patients on HRQoL are partly controversial. This study, which comprised 2913 adult IBD patients, examined HRQoL using the disease-specific IBDQ and the general 15D instruments. The 15D scores of IBD patients were compared with scores of a gender and age matched general population sample. Frequency of IBD symptoms and arrangement of therapy were studied and compared with those of IBD patients in an earlier European study. Furthermore, data of other chronic diseases of the patients were obtained from the Social Insurance Institution s reimbursement register and comorbidity of IBD patients was compared with that of age and gender matched controls. --- Of the respondents, 37% reported that they suffered from disturbing IBD symptoms weekly. In 17% of the patients, the symptoms greatly affected the ability to enjoy leisure activities, and 14% stated that these symptoms greatly affected their capacity to work. Despite that, the great majority (93%) of patients expressed satisfaction with their current treatment, which exceeded the rate observed in the other European patients. The mean IBDQ score was 163, as the possible range is 32-224, and disease activity was strongly correlated with HRQoL. Older age, comorbid diseases, and female gender were also related to impairment of HRQoL. Lower HRQoL scores were seen also in newly-diagnosed patients and in those with a history of surgery, especially after stoma or ileal pouch-anal anastomosis (IPAA) operation. The range of 15D scores was 0.30-1.00, with mean of 0.87. As with the IBDQ, disease activity, older age and history of surgery were correlated with the score. Both the newly-diagnosed patients and patients with a long-lasting disease had lower scores than average even after adjusting for age. The 15D scores of IBD patients were significantly lower than those of the control group. A strong correlation was seen between the 15D and the IBDQ scores. Comorbidity with other chronic diseases was observed in 29% of IBD patients. Connective tissue diseases, chronic obstructive pulmonary diseases, pernicious anaemia, and coronary heart disease (CHD) were significantly increased in patients with IBD. Especially female IBD patients appeared to be at increased risk for CHD, and patients who reported weekly IBD symptoms had a higher risk for having other chronic diseases in addition to IBD. Comorbidity impaired HRQoL, as measured with both generic and disease-specific tools. In conclusion, HRQoL is impaired in IBD patients. An understanding of predictors of HRQoL will help to recognise patients who will need special support.
  • Karppinen, Noora (2014)
    Heart rate variability (HRV) is a noninvasive tool for investigating cardiac autonomic nervous system, especially its parasympathetic branch. HRV is known to be reduced for example in cardiovascular autonomic neuropathy and after myocardial infarction. Several studies have reported reduced HRV in type 1 diabetes patients. Regular exercise is known to increase parasympathetic tone but the effect of training on HRV is somewhat unclear. This study examined HRV during 48 hours after incremental cycling until volitional fatigue in type 1 diabetes patients without cardiac autonomic neuropathy and in healthy controls. HRV was analyzed both at day and night. Subjects’ aerobic capacity was measured. Part of the subjects underwent 6-12 months training intervention, after which the same measurements were repeated. Time-domain, frequency-domain and nonlinear methods were used in HRV analysis. Aerobic capacity was significantly higher in healthy controls than in type 1 diabetes patients (p=0.036). No differences in HRV were found between type 1 diabetes patients and healthy controls. In healthy controls aerobic capacity correlated with LF/HF-ratio (r=-0.711, p=0.014). In type 1 diabetes patients glycosylated hemoglobin (HbA1c) correlated with SDNN (r=-0.645, p=0.023), absolute VLF power (r=-0.648, p=0.023) and SD2 of Poincare plot (r=-0.646, p=0.023). There was a significant increase in aerobic capacity in both groups after training intervention (p<0.05). Training intervention did not cause a significant change in HRV.
  • Karppinen, Noora (2014)
    Heart rate variability (HRV) is a noninvasive tool for investigating cardiac autonomic nervous system, especially its parasympathetic branch. HRV is known to be reduced for example in cardiovascular autonomic neuropathy and after myocardial infarction. Several studies have reported reduced HRV in type 1 diabetes patients. Regular exercise is known to increase parasympathetic tone but the effect of training on HRV is somewhat unclear. This study examined HRV during 48 hours after incremental cycling until volitional fatigue in type 1 diabetes patients without cardiac autonomic neuropathy and in healthy controls. HRV was analyzed both at day and night. Subjects’ aerobic capacity was measured. Part of the subjects underwent 6-12 months training intervention, after which the same measurements were repeated. Time-domain, frequency-domain and nonlinear methods were used in HRV analysis. Aerobic capacity was significantly higher in healthy controls than in type 1 diabetes patients (p=0.036). No differences in HRV were found between type 1 diabetes patients and healthy controls. In healthy controls aerobic capacity correlated with LF/HF-ratio (r=-0.711, p=0.014). In type 1 diabetes patients glycosylated hemoglobin (HbA1c) correlated with SDNN (r=-0.645, p=0.023), absolute VLF power (r=-0.648, p=0.023) and SD2 of Poincare plot (r=-0.646, p=0.023). There was a significant increase in aerobic capacity in both groups after training intervention (p<0.05). Training intervention did not cause a significant change in HRV.
  • Haapala, Markus (Helsingin yliopisto, 2010)
    Miniaturized analytical devices, such as heated nebulizer (HN) microchips studied in this work, are of increasing interest owing to benefits like faster operation, better performance, and lower cost relative to conventional systems. HN microchips are microfabricated devices that vaporize liquid and mix it with gas. They are used with low liquid flow rates, typically a few µL/min, and have previously been utilized as ion sources for mass spectrometry (MS). Conventional ion sources are seldom feasible at such low flow rates. In this work HN chips were developed further and new applications were introduced. First, a new method for thermal and fluidic characterization of the HN microchips was developed and used to study the chips. Thermal behavior of the chips was also studied by temperature measurements and infrared imaging. An HN chip was applied to the analysis of crude oil – an extremely complex sample – by microchip atmospheric pressure photoionization (APPI) high resolution mass spectrometry. With the chip, the sample flow rate could be reduced significantly without loss of performance and with greatly reduced contamination of the MS instrument. Thanks to its suitability to high temperature, microchip APPI provided efficient vaporization of nonvolatile compounds in crude oil. The first microchip version of sonic spray ionization (SSI) was presented. Ionization was achieved by applying only high (sonic) speed nebulizer gas to an HN microchip. SSI significantly broadens the range of analytes ionizable with the HN chips, from small stable molecules to labile biomolecules. The analytical performance of the microchip SSI source was confirmed to be acceptable. The HN microchips were also used to connect gas chromatography (GC) and capillary liquid chromatography (LC) to MS, using APPI for ionization. Microchip APPI allows efficient ionization of both polar and nonpolar compounds whereas with the most popular electrospray ionization (ESI) only polar and ionic molecules are ionized efficiently. The combination of GC with MS showed that, with HN microchips, GCs can easily be used with MS instruments designed for LC-MS. The presented analytical methods showed good performance. The first integrated LC–HN microchip was developed and presented. In a single microdevice, there were structures for a packed LC column and a heated nebulizer. Nonpolar and polar analytes were efficiently ionized by APPI. Ionization of nonpolar and polar analytes is not possible with previously presented chips for LC–MS since they rely on ESI. Preliminary quantitative performance of the new chip was evaluated and the chip was also demonstrated with optical detection. A new ambient ionization technique for mass spectrometry, desorption atmospheric pressure photoionization (DAPPI), was presented. The DAPPI technique is based on an HN microchip providing desorption of analytes from a surface. Photons from a photoionization lamp ionize the analytes via gas-phase chemical reactions, and the ions are directed into an MS. Rapid analysis of pharmaceuticals from tablets was successfully demonstrated as an application of DAPPI.
  • Saarinen, Sampo (2014)
    Nanofluids are a new class of colloids that is generally classified as solid particle suspensions such that the particle diameter is less than 100 nm. In the last decade they have exhibited anomalously high thermal conductivity compared to classical models. Additionally, nanoscale emulsions have shown similar behavior but have gathered less attention than solid particle nanofluids. The optimal preparation of nanoemulsions is not straightforward. Multiple factors have an effect on the final size distribution and therefore optimization is required. Models for the anomalous behavior include effects of the Brownian motion, formation of particle clusters and ordering of liquid into a layer of high conductivity around the particles. In our measurements for nanoscale emulsions, we however observed no significant deviation from the classical models. Besides conduction, nanofluids could also be utilized in convective heat transfer applications. The research on this field is more limited but indicates that increases in heat transfer exist also in convective transport. We perform heat transfer experiments on several n-decane in water nanoemulsions and nanoscale micelle colloids in the transition and turbulent flow regime. Our results indicate that while the thermal properties of the samples were usually worse for convective applications than the reference, the heat transfer properties were similar or better especially at high Reynolds numbers.
  • Sajavaara, Timo (Helsingin yliopisto, 2002)
  • Koponen, Jonna (Helsingin yliopisto, 2009)
    Several excited states of Ds and Bs mesons have been discovered in the last six years: BaBar, Cleo and Belle discovered the very narrow states D(s0)*(2317)+- and D(s1)(2460)+- in 2003, and CDF and DO Collaborations reported the observation of two narrow Bs resonances, B(s1)(5830)0 and B*(s2)(5840)0 in 2007. To keep up with experiment, meson excited states should be studied from the theoretical aspect as well. The theory that describes the interaction between quarks and gluons is quantum chromodynamics (QCD). In this thesis the properties of the meson states are studied using the discretized version of the theory - lattice QCD. This allows us to perform QCD calculations from first principles, and "measure" not just energies but also the radial distributions of the states on the lattice. This gives valuable theoretical information on the excited states, as we can extract the energy spectrum of a static-light meson up to D wave states (states with orbital angular momentum L=2). We are thus able to predict where some of the excited meson states should lie. We also pay special attention to the order of the states, to detect possible inverted spin multiplets in the meson spectrum, as predicted by H. Schnitzer in 1978. This inversion is connected to the confining potential of the strong interaction. The lattice simulations can also help us understand the strong interaction better, as the lattice data can be treated as "experimental" data and used in testing potential models. In this thesis an attempt is made to explain the energies and radial distributions in terms of a potential model based on a one-body Dirac equation. The aim is to get more information about the nature of the confining potential, as well as to test how well the one-gluon exchange potential explains the short range part of the interaction.
  • Nihtilä, Annamari (Helsingin yliopisto, 2014)
    A reform to Dental Care legislation in 2002 abolished age limits restricting adults use of public dental services in Finland. This Dental Reform aimed to increase equity by improving adults´ access to care and reducing cost barriers. The adult population´s increased demand for dental care put pressure on the Public Dental Service (PDS). The aim of this study was to compare heavy and low use of dental services in the PDS of Espoo in order to identify reasons for heavy use and to suggest improvements to care provision. This study is based on register data. All patients who had visited the PDS of Espoo in 2004 (n=63 850) were divided into two groups: children and adolescents and adults. Within each group, all patients who had made six or more dental visits to the PDS in 2004 were defined as heavy users of oral health services and all the patients who had had three or fewer visits as low users. A random sample of 320 adult patients and a 245 children and adolescent patients was drawn from each group. All adult heavy and low consumers of dental services identified in 2004, were followed for five years. Information on age, sex, number and types of visits, oral health status and treatment provided was collected from treatment records. Seven per cent of the children and adolescents in 2004 could be classified as heavy users and the main reasons of heavy use were high numbers of orthodontic treatment occasions provided by dentists and high numbers of decayed teeth in a small number of children. For adults, 10% were heavy users. A need for complicated treatment, dentists´ and dental hygienists´ lack of experience of adult dental care and lack of specialist resulted in high numbers of visits for these patients. The adult heavy users were older and had lower social status than low users. Of these baseline adult heavy users 11% persisted as chronic frequent users during 2005-2009. Typical for adult heavy use in the baseline and the follow-up study was a lack of proper examinations, poor quality of periodontal diagnosis, lack of preventive care, and a cycle of repetitive repair or replacement of restorations, often as emergency treatment. Fixed prosthetic treatment was seldom used in the PDS of Espoo. The PDS should seek to early identify possible heavy users and they should be offered a comprehensive approach to treatment and a responsible team of a dentist and dental hygienist. In order to manage adult dental health effectively, the PDS should encourage regular examinations, treatment plans and recall visits based on patients´ oral health and risk factors.
  • Hietanen, Piritta (1996)
  • Tikkanen, Minna (2014)
    Tämän tutkimuksen päätavoitteena oli selvittää ayrshire-rodun hedelmällisyyden, runkorakenteen ja maitotuotoksen väliset geneettiset korrelaatiot sekä laskea ominaisuuksille periytymisasteet. Aineistossa oli mukana 21 450 ayrshire-rotuista eläintä 2647 eri karjasta. Eläimet olivat syntyneet vuosien 1994 – 2005 aikana, ja olivat 1652 sonnin tyttäriä. Tutkittavia hedelmällisyysominaisuuksia olivat hiehojen siemennyskauden pituus ja siemennysten lukumäärä sekä ensikoiden lepokauden pituus. Maitotuotosominaisuudet olivat ensimmäisen kerran poikineiden 305 päivän maitotuotos ja elinikäistuotos sekä runko-ominaisuudet olivat takakorkeus, rungon syvyys, rinnan leveys, lypsytyyppisyys, selkälinja, lantion leveys ja lantion kulma. Satunnaistekijöiden varianssikomponenttien sekä periytymisasteiden arvioimiseen käytettiin DMU-ohjelmaa Restricted Maximum Likelihood (REML) –menetelmää käyttäen. Periytymisasteen arvioksi saatiin ensikkotuotokselle 0,28 ja elinikäistuotokselle 0,08. Hedelmällisyysominaisuuksien periytymisasteiden arviot olivat hyvin alhaisia (0,02 – 0,03) sekä hiehoilla että ensikoilla. Runko-ominaisuuksien periytymisaseet vaihtelivat välillä 0,10 – 0,43. Korkeimmat periytymisasteen arviot olivat takakorkeudella (0,43) ja lantion kulmalla (0,27). Suurimmat positiiviset korrelaatiot saatiin lypsytyyppisyyden ja ensikkotuotoksen (0,51) sekä lypsytyyppisyyden ja elinikäistuotoksen (0,45) välille, ja suurin negatiivinen korrelaatio saatiin selkälinjan ja ensikkotuotoksen (-0,33) välille. Ensikoiden runko-ominaisuuksista rinnan leveydellä ja lantion kulmalla oli kohtalainen geneettinen yhteys lepokauteen. Rungon syvyys, lantion leveys ja kulma korreloivat merkitsevästi hiehojen tiinehtymisen kanssa. Hiehojen hedelmällisyysominaisuuksien ja elinikäistuotoksen väliset geneettiset korrelaatiot olivat kohtalaisia ja positiivisia. Tässä tutkimuksessa lepokauden ja tuotosominaisuuksien välillä ei havaittu perinnöllistä yhteyttä. Hedelmällisyys ja elinikäistuotos ovat vain heikosti periytyviä ominaisuuksia. Runkorakenteen ja ensikkotuotoksen parantaminen jalostuksella on kohtalaisen nopeaa, koska ne periytyvät keskinkertaisesti. Tämän tutkimuksen perusteella joidenkin runko-ominaisuuksien valinta edistää ensikkotuotosta heikentäen samalla hedelmällisyyttä ja elinikäistuotosta. Hiehojen huono hedelmällisyys oli yhteydessä korkean elinikäistuotoksen kanssa, kuitenkaan ei ole mielekästä painottaa valinnassa huonoa hiehojen hedelmällisyyttä.
  • Lemström, Ossi (1999)
    Työ on jatkoa laajemmalle Namibian luterilaisen kirkon kirkonkirjoihin perustuvalle väestöhistorialliselle tutkimushankkeelle, josta on aikaisemmin saatu tuloksia Ambomaan osalta. Tässä on aineistona Kavangon alueelta kerätty aineisto vuosina 1935-1985 avioituneista. Tavoitteena oli arvioida aineiston laatua ja analysoida hedelmällisyyttä ja kuolleisuutta alueella sekä niissä viime vuosikymmeninä tapahtuneita muutoksia. Tuloksia verrataan projektin pääaineistoon Ambomaalta. Kavangon kirkonkirja-aineisto on pieni. Kolmen seurakunnan - Nkurenkurun, Mupinin ja Ruparan kirkonkirjoista on perherekonstituutio-menetelmällä kerätty tiedot 890 pariskunnasta, joissa on 886 miestä ja 885 naista (osa avioituu uudestaan) sekä 3289 lasta (joista 42 ottolasta). Kirkonkirjoista on kerätty tiedot avioitumisesta, kuolemista, syntymistä, kasteista, muutoista, seurakunnista erottamisista ja takaisinotoista. Perheitä on seurattu vuoden 1995 loppuun. Aineiston laatu osoittautui selkeästi Ambomaan aineistoa huonommaksi. Kavangolla kirkonkirjoja ei ole pidetty niin tarkasti kuin Ambomaalla. Erityisesti syntymähetki- ja kuolinhetkitiedot oli huonommin tiedossa. Hedelmällisyydessä on Kavangon kirkonkirja-aineistossa nähtävissä selkeä nousu 50- ja 60-luvulla sekä pudotus 70-luvulla. Mahdolliset muutokset peittyvät kuitenkin lasten kasteiässä tapahtuvien muutosten alle. Todennäköisesti hedelmällisyys on pysynyt varsin korkeana ja kokonaishedelmällisyysluku lähellä seitsemää koko tarkastelujakson ajan, eli ainakin yhtä korkealla kuin Ambomaalla. Hedelmällisyyden täsmällisemmän tason ja siinä tapahtuvien muutosten estimointi edellyttäisi jonkinlaista tietoa lapsikuolleisuuden tasosta ja ikäjakaumasta. Lisäksi selvää lienee, että ennen avioitumista synnyttäneiden naisten määrä on noussut, mikä näkyy myös nuorten naisten hedelmällisyyden kasvuna. Kavangon kirkonkirja-aineisto on liian pieni miesten kuolleisuuden vuosittaisen tason laskemiseksi tai edes kehityksen suunnan arvioimiseksi. Käyttämällä vuoden 1991 väestölaskennan lapsikuolleisuustietoja estimoinnissa saatiin jaksolle 1960-1995 miesten elinajanodotteeksi syntyessä 57.5 vuotta, mikä on 3-4 vuotta vähemmän kuin Ambomaalla. Lisäksi näyttäisi siltä, että myös Kavangolla Ambomaan tavoin kuolleisuus olisi alhaista jo 60-luvulla, joten kuolleisuudessa olisi tapahtunut voimakas lasku jo aikaisenunin. Kuten Ambomaallakin, naisten kuolemat on merkitty Kavangolla kirkonkirjoihin huonommin kuin miesten. Ambomaalla naisten kuolleisuuden analyysin mahdollisti kirkonkirjoihin merkittyjen kuolemien riittävän kattava keskittyminen 20-39 -vuotiaisiin. Kavangolla tällaista keskittymää ei ole ja aineisto on liian pieni naisten kuolleisuuden analyysia varten. Lasten kohdalla tilanne on sama, kuolemantapauksia on aineistossa liian vähän. Jonkinlaisen arvion lasten (tai imeväisikäisten) kuolleisuudesta voisi ehkä tehdä, jos olettaisi hedelmällisyyden vakioksi ja erot aineistosta lasketussa hedelmällisyydessä johtuisivat vain ennen kastamista kuolleista lapsista. Mutta Ambomaallakin havaittiin vaihtelua hedelmällisyydessä.
  • Saaristo, Noora (2014)
  • Eerola, Kari (2008)
    The current financial crisis has raised considerable debate about the risk management practices of banks and other financial institutions. In particular, there have been concerns about systemic risk that basically means the possible consequences of bank failures on the economic activity, growth and employment. These worries originate from the common insight that the troubles in financial sector may spill over to the real economy. In this thesis, I focus on hedge funds’ risks. Hedge funds are specialized investment vehicles which try to provide above average risk-adjusted returns due to the presumably superior skills of their management. The absence of regulation is an important feature of the hedge funds, and it implies less visibility and less observable risks. If these opaque risks materialize, the financial distress might spill over the financial system due to the tight links between the hedge funds and banks. This is called financial contagion. In the first part of this thesis, I identify the hedge fund's risk profile and derive some quantitative risk management tools using a statistical concept called Value-at-Risk. Value-at-Risk tells the maximum loss a portfolio holder can suffer due to market risk over a pre-specified time period, given some probability. Specifically, since skewness and excess kurtosis often characterize the hedge fund return distribution indicating the possibility of a very large loss, models based on the normal distribution are not appropriate. Statistical theory provides alternative ways to estimate Value-at-Risk counting for the skewness and excess kurtosis. In this thesis I exploit the useful properties of extreme value theory, the Cornish-Fisher expansion and Monte Carlo simulation to derive the estimators for Value-at-Risk. In addition, liquidity risk is the central ingredient of systemic risk and also present in the hedge funds’ risk profile. Therefore, I derive liquidity-adjusted Value-at-Risk as well. In the second part of this thesis, I focus on the hedge funds' role as to financial stability. I follow the general model by Allen & Gale (2000), in which contagion is modeled as an equilibrium phenomenon. In this model, external liquidity shock hitting into one sector of the financial market can spread over the entire financial system and bring down all financial institutions. Of course, in the approach of this thesis the hedge fund sector faces the shock and thus initiates the distress. However, even in the presence of the liquidity shock, this spillover is not inevitable, but is crucially dependent on the size of the shock and especially on the financial buffers, which can loosely be interpreted as the risk management practices.
  • Eerola, Kari (2008)
    Meneillään oleva finanssikriisi on herättänyt huomattavaa keskustelua pankkien ja muiden rahoitusinstituutioiden riskienhallintakäytännöistä. Erityistä huolta on herättänyt niin kutsuttu systeemiriski. Tämä tarkoittaa käytännössä pankkien konkurssien mahdollisia haitallisia seurauksia taloudelliseen aktiviteettiin, kasvuun ja työllisyyteen. Nämä huolet ovat seurausta yleisesti hyväksytystä käsityksestä, jonka mukaan rahoitussektorin ongelmat voivat levitä myös reaalitalouden puolelle. Tässä tutkielmassa keskityn hedge rahastojen riskeihin. Hedge rahastot ovat erikoistuneita sijoitusvälineitä, jotka yrittävät tarjota keskimääräistä parempaa riskikorjattua tuottoa täysimittaisesti hyväksikäyttämällä salkunhoitajien mahdollisia ylivertaisia kykyjä. Hedge rahastoja ei reguloida rahoitusmarkkinaviranomaisten taholta, mikä tekee niistä ja niiden riskeistä läpinäkymättömiä ja vaikeasti huomattavia. Jos nämä riskit realisoituvat, tiiviit yhteydet pankkien ja hedge rahastojen välillä saattavat aiheuttaa vaikeuksia koko rahoitusjärjestelmälle. Tätä kutsutaan taloudelliseksi tartuttamiseksi (englanniksi financial contagion). Tutkielman ensimmäisessä osassa identifioin hedge rahaston riskiprofiilin, ja johdan joitakin kvantitatiivisia riskienhallintavälineitä käyttäen Value-at-Risk (riskin arvo) -käsitettä. Value-at-Risk perustuu tilastotieteelliseen malliin, ja se kertoo suurimman tappion, jonka sijoitusportfolion haltija voi kärsiä markkinariskin johdosta tietyn ajan kuluessa tietyllä todennäköisyydellä. Hedge rahastojen tuottojakaumat ovat usein vinoja ja huipukkaita, mikä merkitsee hyvin suuren tappion mahdollisuutta. Tämän seurauksena myöskään normaalijakaumaan perustuvat mallit eivät sovellu Value-at-Risk -arvon laskemiseen hedge rahastojen tapauksessa. Tilastotiede tarjoaa kuitenkin vinokkuuden ja huipukkuuden huomioivia malleja. Tässä tutkielmassa hyödynnän äärimmäisten arvojen teoriaa (englanniksi extreme value theory), Cornish-Fisher -kehitelmää sekä Monte Carlo -simulaatiota Value-at-Risk estimaattorien johtamiseksi. Likviditeettiriski on aivan keskeinen tekijä systeemiriskin tapauksessa, kuten myös hedge rahastojen riskiprofiilissa. Tämän takia osoitan myös, miten Valuet-at-Risk estimaattoriin voidaan lisäksi likviditeettiriski. Tutkielman toisessa osassa keskityn rahoitusjärjestelmän vakauteen ja siihen, mikä rooli hedge rahastoilla on tämän vakauden toteutumisessa. Mukailen Allenin & Galen (2000) mallia, jossa taloudellinen tartuttaminen mallinnetaan tasapainoilmiönä. Tässä mallissa ulkoinen likviditeettisokki iskee rahoitusmarkkinoiden yhteen sektoriin ja saattaa tietyn ehdoin levitä sieltä yli koko rahoitusjärjestelmän kaataen kaikki rahoitusinstituutiot. Tässä tutkielmassa luonnollisesti hedge rahasto -sektori kohtaa likviditeettisokin ja on täten vaikeuksien alullepanija. Kuitenkin sokin leviäminen on kriittisesti riippuvainen sokin koosta ja erityisesti pankkien puskureista eli likvideistä rahavaroista, jotka voidaan väljästi tulkita riskienhallinkäytännöiksi.
  • Nikkanen, Saara (2009)
    Tässä pro gradu -tutkielmassa pureudun terveys- ja sosiaalialan koulutetun henkilöstön ammattijärjestö Tehyn vuoden 2007 työtaistelun herättämään keskusteluun sanomalehdissä. Tarkoituksenani on selvittää, millä tavalla työtaistelusta kirjoitettiin ja millaisia yhteiskunnallisia teemoja sen puitteissa nostettiin julkisen keskustelun keskiöön. Tutkimusaineistoni koostuu yhteensä 394 lehtileikkeestä. Keskityn tarkastelemaan nimenomaan toimittajien ja median roolia draaman voimalähteenä, joten tutkimukseni on rajautunut pääkirjoituksiin ja kolumneihin. Ne mielletään toimittajien näkyviksi keinoiksi ottaa kantaa yhteiskunnalliseen keskusteluun, ja ne peilaavat sitä, miten yhteiskunnassamme rakennetaan sosiaalista ja moraalista järjestystä. Tutkimusmenetelmäni on laadullinen. Hahmottelen pääkirjoitusten ja kolumnien työtaistelusta muodostamaa kuvaa hieman harvemmin viestinnän tutkimuksessa käytetyn draama-analyysin keinoin. Erittelen aineistostani tapahtumien jännitteitä ja käännekohtia jakamalla ne näytöksiin Gustav Freytagin draaman pyramidimallin avulla. Tutkimukseni viitekehyksen muodostavat ajatukset viestinnästä yhteisöllisyytenä ja sosiaalisena rituaalina, sosiaalisena draamana. Lisäksi hyödynnän pohdinnassani muun muassa moraaliteorioita sekä feminististä teoriaa sekä avaan hoitoalan kutsumustyön luonnetta. Tehyn työtaistelun tapahtumista muodostui kiihkeä yhtenäinen mediadraama, jonka juonenkäänteitä ruodittiin aktiivisesti myös toimittajien itsensä toimesta. Hoitajien palkkojen oikeellisuudesta käyty kiivas keskustelu lähti käyntiin Tehyn teettämästä palkkakyselystä. Keskustelu ja tapahtumien uutisointi etenivät vaalilupausten, eduskuntavaalien ja syksyn kunta-alan palkkaneuvottelujen kautta kohti lopullista huipentumaansa, Tehyn irtautumista neuvottelurintamasta ja jatkamista palkkataistoa yksin. Tätä seurannut traaginen käänne, Tehyn tavoitteiden ja työtaistelukeinon konkretisoituminen joukkoirtisanoutumisiksi kiihdytti keskustelun äärimmilleen. Alkuvuonna Tehyn palkkavaateita voimakkaastikin tukeneiden pääkirjoitusten ja kolumnien sävy muuttui negatiivisemmaksi, ja sekä Tehyn että hallituksen toimia arvosteltiin jyrkästi. Pääkirjoituksissa ja kolumneissa rakennettiin kuvaa suomalaisesta hoitajasta sekä keskusteltiin yhteiskuntamme arvoista ja moraalista. Sukupuoli ja siihen liitetyt kulttuuriset piirteet sekä hoitotyön kutsumusluonne korostuivat työtaistelun kirjoituksissa. Tehyn työtaistelu paljasti, miten historiallinen naisten yksityisen hoiva- ja uusintamistyön näkymättömyys sekä vähäinen tuotannollinen arvostus määrittävät naistyötä tänäkin päivänä. Vaikka hoitajien palkkakuoppa tunnustettiin, se nähtiin jollain tavalla olemuksellisena osana yhteiskuntamme rakenteita, ja sukupuolihierarkiasta pois pyrkivät hoitajat leimattiin ahneiksi. Lisäksi perinteisten arvojen ja uusien markkinataloudellisten arvojen törmäyksessä kutsumustyön ja hoivatyön traditio tulivat voimakkaasti näkyviin ja kohosivat yli muiden arvojen.
  • Vainio, Jenny (Helsingin yliopisto, 2012)
    This study takes its point of departure in the gender-gap phenomenon observed in most academic communities worldwide. The statistics show that academic women are less likely to advance in their university careers than their male colleagues. The female underrepresentation is especially severe in the scientific field of physics, which is the focus of this study. In order to further understand the social and historical processes behind the gender-gap phenomenon in physics, three concepts were chosen as theoretical resources of this study. Hegemony (Gramsci) captures the dialectical processes of resistance and integration behind social consent. Contradiction (Ilyenkov, Engeström) refers to the dynamics of socio-historical changes in Finnish academia. Gender is understood as a set of social and organizational processes (Acker) through which gender difference is produced in the context of university physics. This study is based on qualitative data, namely semi-structured interviews with 36 Finnish physicists, both current and former university staff. Three intermediate concepts, alignments, turning points and discursive manifestations of contradictions, were utilized as bridging the empirical data and theoretical concepts. As a data-analysis method, tools of discourse analysis and narrative analysis were used. When considering the data analysis results from the point of view of gendered career paths in physics, it can be suggested that men are more adapted to the prevailing images and norms of research work. They identified themselves with the idea of a lone scientist more often than women who preferred teamwork. Moreover, men expressed more willingness to enter the academic competition than women and it was generally easier for them to prioritize work over family than for women. At the same time, women had to adapt to the male-dominated workplace-interaction in order to survive sexual harassment. Women performed more willingness to take up administrative and supportive tasks than men who preferred research work. These different preferences and modes of interaction in the academic work might contribute to the fact that women and men are likely to pursue on different academic careers. The data analysis also indicates a set of gendered processes and historical contradictions in the academic community of physics. For instance, sexual harassment can be interpreted as an interactional gendered process that has its roots in a contradiction between traditional male- dominated interactional rules and the current community of physicists where also women are present. The issue of reconciliation of work and family suggests a symbolic gendered process where the ideal image of a scientific worker implies a male researcher without family duties. Here, a contradiction between the traditional rules of organizing research work and the contemporary community of both male and female physicists can be traced. The above-presented data-analysis results inform the concept of hegemony. The dialectical notion of hegemony calls for identifying processes through which hegemony becomes reproduced and/or contested. In the data, instances of integration and resistance were gendered and clustered around two poles. In general, women expressed resistance against what can be called a traditional mode of academic work. At the same time, men integrated with it. On the contrary, men strongly resisted some of the current developmental trends in the academic working environment whereas women seemed to integrate with them more easily. Based on these observations, it can be suggested that, in the context of Finnish universities, two types of hegemonic forces are at play. Male interviewees found their site of integration in the hegemonic idea of traditional academic work, whereas female interviewees expressed resistance against some of its features. Male resistance was targeted at the emerging hegemonic idea of a managerial university whereas female interviewees could integrate with it to an extent.
  • Westerlund, Fredrik (Helsingin yliopisto, 2014)
    This PhD thesis is an extended critical investigation of Martin Heidegger s influential account of the problem of phenomenality, i.e., of how things show up as meaningful phenomena in our experience. As such, it is also a study of his effort to develop and probe the question of phenomenology, i.e., what it means to see, understand, and articulate such phenomena. The aim of the thesis is both historical and systematic. On the one hand, it offers a unified interpretation of how Heidegger s struggle with the problem of phenomenality unfolds during the main stages of his philosophical development, from the early Freiburg lecture courses 1919-1923, over the Marburg years and the publication of Being and Time in 1927, up to his later thinking stretching from the mid 1930s to the early 1970s. It is argued that the problem of phenomenality constitutes one of the core problems that Heidegger is concerned with from beginning to end, and that focusing on this problem allows us to shed new light on the philosophical logic and motives behind the main changes that his thinking undergoes along the way. On the other hand, the thesis examines both the philosophical power and the problems and ambiguities of Heidegger s consecutive attempts to account for the structure and dynamics of phenomenality. In particular, it critically interrogates Heidegger's basic idea that our experience of meaningful phenomena is determined by our prior understanding of the historical contexts of meaning in which we always already live. A central argument of the thesis is that Heidegger s conception of the historical structure of phenomenality raises the decisive question of how to distinguish between historical prejudice and primordial understanding, and that Heidegger s inability to answer this question in Being and Time generates a deep ambiguity between his program of historical-destructive thinking and his employment of a Husserlian intuition-based phenomenological method in his concrete investigation. Moreover, it is argued that Heidegger s later thinking of the clearing/event of being is centrally motivated by the effort to answer precisely this question by showing how a historical world can arise and give itself as a binding destiny. Ultimately, however, the thesis suggests elaborating on the criticisms previously presented by, e.g., Ernst Tugendhat and Emmanuel Levinas that Heidegger s radical historicization of phenomenality makes him unable to account either for the truth of our understanding or for the ethical-existential significance of other persons.