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  • Lehtonen, Aleksi (Helsingin yliopisto, 2005)
  • Pienimäki, Arttu (2014)
    The most extensive dry forest and woodland formation in sub-Saharan Africa, including Mozambique, is formed by miombo woodlands. Because of their wide distribution, the miombo woodlands carry significance in global carbon cycle. Previous studies have indicated that while the miombo aboveground carbon stocks appear modest in comparison with tropical rainforests, they have a potential to retain high stocks of soil organic carbon. The miombo landscape is nowadays characterized by widespread deforestation and forest degradation, with woodlands being replaced by anthropogenic land uses such as small-scale agriculture and charcoal harvesting. A new land use type spreading in northern Mozambique is formed by industrial forest plantations. The emerging plantations further change the landscape in transition, allegedly affecting the carbon stocks in the process as well. The purpose of this study was to quantify carbon stocks on locally relevant land use classes in Niassa province, northern Mozambique, and evaluate the change of carbon stocks caused by forest plantations. Six major land use classes were identified: dense miombo, open miombo, other woody vegetation, fallow land, eucalypt plantations and pine plantations. A sample plot grid was laid on chosen areas representing each of the classes. Vegetation aboveground carbon stocks (trees, shrubs and herbaceous vegetation) were recorded in the inventory and topsoil (30 cm) was sampled for soil organic carbon content, to be determined in laboratory. Vegetation belowground carbon stocks were calculated based on existing root to shoot ratios. Since plantations were generally juvenile on the study area, their average yield during rotation period was estimated based on growth models to provide comparable results. Forest plantations were found to have carbon stocks of the same order of magnitude as the two miombo land use classes. Open and dense miombo carried mean vegetation aboveground carbon stocks of 27.47 ± 5.77 and 37.65 ± 7.20 Mg ha-1 respectively, and mean total carbon stocks of 67.81 ± 17.09 and 86.81 ± 18.91 Mg ha-1 respectively, which was consistent with pre-existing results. Pine plantations placed in between with a partially modelled total aboveground mean carbon stock of 34.59 Mg ha-1, whereas the corresponding figure for eucalypt plantations was 21.04 Mg ha-1. Dense miombo had the highest mean total carbon stock of all the land use classes, and fallow land the smallest with 42.59 Mg ha-1. Soil organic carbon did not demonstrate statistically significant differences between any of the land use classes. The result was unexpected, and may be explained either by (i) limited time frame since the land use conversions or (ii) soil mineralogical properties buffering carbon stock changes.
  • Alam, Syed Ashraful (Helsingin yliopisto, 2013)
    Understanding the carbon (C) sequestration potential of drylands requires knowledge of the stocks of C in soils and biomass and on the factors affecting them. The overall aim of the study was to determine and evaluate the variation in the C stocks and water balance of Acacia savannah woodlands across the dryland (arid and semi-arid) region (10-16 ºN; 21-36 °E) of the former Sudan (now mainly in the Republic of the Sudan) and how they are related to climatic factors and may be affected by climate change. The role played by small but numerous brick making industries on woodland deforestation in the region and greenhouse gas production was also investigated. The study region is often referred to as the gum belt because it is the world s major source of gum Arabic, which is harvested from Acacia trees. The soils in the centre and west of the region are mainly Arenosols (sandy soils) and those in the eastern part are mainly Vertisols (clay soils). The soils are C poor and often in a degraded state. This dissertation consists of a summary section and four articles (Study I, II, III and IV). Study I focuses on fuelwood consumption by the brick making industries (BMIs) and associated deforestation and greenhouse gas (GHG) emissions. In Study II the C densities (g C m-2) of the woodland tree biomass and soil (1 m) for 39 map sheets covering the study region were determined from national forest inventory data and global soil databases and the dependence on mean annual precipitation (MAP) and mean annual temperature (MAT) determined. The water balance of savannah woodlands for the same 39 map sheets was modelled in Study III and the variation in water balance components across the region evaluated. The potential impacts of climate change on woodland biomass C density and water-use (actual evapotranspiration, AET) was analysed for eight of the map sheets in Study IV. Sudanese BMIs consume a considerable amount of fuelwood that mainly comes from unsustainably managed woodland and contributes to deforestation and GHG emissions (Study I). While GHG emissions from BMIs only account for a small part of Sudan s total GHG emissions, the associated deforestation and land degradation is of concern. Implementation of better regulation, use of biomass fuel from sustainable sources and technological improvement in BMIs kilns will reduce deforestation and GHG emissions. Savannah woodland C densities, both biomass and soil, were low and clearly below potential C sequestration capacity (Study II). The loss of trees across the region was indicated by very low biomass C density values in comparison to modelled NPP (net primary production) values. The estimated SOC densities although low, were higher than reported in some recent soil C studies from the region. This was attributed to the use of old data in the global soil database and indicates the degree of land degradation and loss of SOC that has taken place over the last few decades. However, in spite of woodland and soil degradation, biomass C and SOC densities remained positively and significantly correlated with each other and both were significantly correlated to MAP. The results highlighted the need for improved land-use management and stewardship, which should involve increasing the cover of trees, and the need for up-to-date regional and integrated soils and forest (woodland) inventories to be made. Water-use (AET) of savannah woodlands is strongly limited by rainfall. Rainfall exceeded AET only during some of the wet season months resulting in a small increase in soil moisture storage and production of surface runoff for some areas (Study III). Drainage (to groundwater) was negligible. Since AET was strongly limited by MAP, AET for both Arenosol and Vertisol soil types increased southwards across the study region. Runoff also increased southwards across the study region for both soil types but were highest in south western and eastern areas. The restoration of woodlands may be expected to improve the soil-water conditions. Compared to baseline (1961-1990) climate values, General Circulation Model (GCM) based results for 2080s indicated that MAT would increase across the study region but that MAP would either increase or decrease depending on climate change scenario (Study IV). Biomass C densities will be significantly affected by climate change. However, the impact varies with climate change scenario, with either increases or decreases in biomass C density being indicated for the same area. In general, water-use on Arenosols will increase while that on Vertisols will decrease. The largest relative changes in AET were associated with the areas receiving the lowest rainfall. Thus, even if MAP increases, the increase will have little impact on biomass levels in the driest areas of the region.
  • Eerola, Anneli (Helsingin yliopisto, 2007)
    Background: The incidence of all forms of congenital heart defects is 0.75%. For patients with congenital heart defects, life-expectancy has improved with new treatment modalities. Structural heart defects may require surgical or catheter treatment which may be corrective or palliative. Even those with corrective therapy need regular follow-up due to residual lesions, late sequelae, and possible complications after interventions. Aims: The aim of this thesis was to evaluate cardiac function before and after treatment for volume overload of the right ventricle (RV) caused by atrial septal defect (ASD), volume overload of the left ventricle (LV) caused by patent ductus arteriosus (PDA), and pressure overload of the LV caused by coarctation of the aorta (CoA), and to evaluate cardiac function in patients with Mulibrey nanism. Methods: In Study I, of the 24 children with ASD, 7 underwent surgical correction and 17 percutaneous occlusion of ASD. Study II had 33 patients with PDA undergoing percutaneous occlusion. In Study III, 28 patients with CoA underwent either surgical correction or percutaneous balloon dilatation of CoA. Study IV comprised 26 children with Mulibrey nanism. A total of 76 healthy voluntary children were examined as a control group. In each study, controls were matched to patients. All patients and controls underwent clinical cardiovascular examinations, two-dimensional (2D) and three-dimensional (3D) echocardiographic examinations, and blood sampling for measurement of natriuretic peptides prior to the intervention and twice or three times thereafter. Control children were examined once by 2D and 3D echocardiography. M-mode echocardiography was performed from the parasternal long axis view directed by 2D echocardiography. The left atrium-to-aorta (LA/Ao) ratio was calculated as an index of LA size. The end-diastolic and end-systolic dimensions of LV as well as the end-diastolic thicknesses of the interventricular septum and LV posterior wall were measured. LV volumes, and the fractional shortening (FS) and ejection fraction (EF) as indices of contractility were then calculated, and the z scores of LV dimensions determined. Diastolic function of LV was estimated from the mitral inflow signal obtained by Doppler echocardiography. In three-dimensional echocardiography, time-volume curves were used to determine end-diastolic and end-systolic volumes, stroke volume, and EF. Diastolic and systolic function of LV was estimated from the calculated first derivatives of these curves. Results: (I): In all children with ASD, during the one-year follow-up, the z score of the RV end-diastolic diameter decreased and that of LV increased. However, dilatation of RV did not resolve entirely during the follow-up in either treatment group. In addition, the size of LV increased more slowly in the surgical subgroup but reached control levels in both groups. Concentrations of natriuretic peptides in patients treated percutaneously increased during the first month after ASD closure and normalized thereafter, but in patients treated surgically, they remained higher than in controls. (II): In the PDA group, at baseline, the end-diastolic diameter of LV measured over 2SD in 5 of 33 patients. The median N-terminal pro-brain natriuretic peptide (proBNP) concentration before closure measured 72 ng/l in the control group and 141 ng/l in the PDA group (P = 0.001) and 6 months after closure measured 78.5 ng/l (P = NS). Patients differed from control subjects in indices of LV diastolic and systolic function at baseline, but by the end of follow-up, all these differences had disappeared. Even in the subgroup of patients with normal-sized LV at baseline, the LV end-diastolic volume decreased significantly during follow-up. (III): Before repair, the size and wall thickness of LV were higher in patients with CoA than in controls. Systolic blood pressure measured a median 123 mm Hg in patients before repair (P < 0.001) and 103 mm Hg one year thereafter, and 101 mm Hg in controls. The diameter of the coarctation segment measured a median 3.0 mm at baseline, and 7.9 at the 12-month (P = 0.006) follow-up. Thicknesses of the interventricular septum and posterior wall of the LV decreased after repair but increased to the initial level one year thereafter. The velocity time integrals of mitral inflow increased, but no changes were evident in LV dimensions or contractility. During follow-up, serum levels of natriuretic peptides decreased correlating with diastolic and systolic indices of LV function in 2D and 3D echocardiography. (IV): In 2D echocardiography, the interventricular septum and LV posterior wall were thicker, and velocity time integrals of mitral inflow shorter in patients with Mulibrey nanism than in controls. In 3D echocardiography, LV end-diastolic volume measured a median 51.9 (range 33.3 to 73.4) ml/m² in patients and 59.7 (range 37.6 to 87.6) ml/m² in controls (P = 0.040), and serum levels of ANPN and proBNP a median 0.54 (range 0.04 to 4.7) nmol/l and 289 (range 18 to 9170) ng/l, in patients and 0.28 (range 0.09 to 0.72) nmol/l (P < 0.001) and 54 (range 26 to 139) ng/l (P < 0.001) in controls. They correlated with several indices of diastolic LV function. Conclusions (I): During the one-year follow-up after the ASD closure, RV size decreased but did not normalize in all patients. The size of the LV normalized after ASD closure but the increase in LV size was slower in patients treated surgically than in those treated with the percutaneous technique. Serum levels of ANPN and proBNP were elevated prior to ASD closure but decreased thereafter to control levels in patients treated with the percutaneous technique but not in those treated surgically. (II): Changes in LV volume and function caused by PDA disappeared by 6 months after percutaneous closure. Even the children with normal-sized LV benefited from the procedure. (III): After repair of CoA, the RV size and the velocity time integrals of mitral inflow increased, and serum levels of natriuretic peptides decreased. Patients need close follow-up, despite cessation of LV pressure overload, since LV hypertrophy persisted even in normotensive patients with normal growth of the coarctation segment. (IV): In children with Mulibrey nanism, the LV wall was hypertrophied, with myocardial restriction and impairment of LV function. Significant correlations appeared between indices of LV function, size of the left atrium, and levels of natriuretic peptides, indicating that measurement of serum levels of natriuretic peptides can be used in the clinical follow-up of this patient group despite its dependence on loading conditions.
  • Granholm, Mikael (1993)
    In veterinary practice intraveneous anaesthesia has numerous advantages. An important advantage is the ease and rapidity of induction. Compared to administration of inhalant anaesthetics, a minimum of apparatus is necessary in administration of intraveneous anaesthetic agents. The possibility of antagonization of certain drugs used as intraveneous anaesthetics increases the safety of anaesthesia. The unpleasant recovery period can also be shortened, which for a busy veterinarian and also the owner can be of great relief. Ideally, a postoperative patient should be conscious, co-operative, calm and free of pain.This will provide better homeostasis of vital functions, allow early diagnosis and treatment of complications and decrease the need for nursing care. The aim of these studies was to analyze the sedative/ analgetic / anaesthetic, cardiovascular and respiratory effects produced by a combination of medetomidine and climazolam at two different dose levels (1.5 mg/kg and 3.0 mg/kg). Climazolam was also combined with fentanyl. Antagonization followed anaesthesia, using atipamezole, nalorphine and a new benzodiazepine antagonist, sarmazenil. 7 laboratory beagles were used inthis experimental study. In combination with medetomidine, climazolam produced smooth anaesthesia and had only small effects on the cardiovascular and respiratory system. Total analgesia was not achived. Intubation was easily performed. The antagonization proved to be fast and complete. When combining climazolam with fentanyl, dose levels were chosen according to previous studies (Erhardt et al., 1986). The anaesthesia was light and short, probably due to the short action of fentanyl. This combination depressed the respiratory system in a much larger scale than the combination of medetomidine and climazolam did. Antagonization was effective.
  • Ruonavaara, Aila (1953)
  • Salmi, Samuli (Helsingin yliopisto, 2012)
    This dissertation concentrates on a particular exemplification of the ideal of the unity of science in the history of twentieth-century philosophy. Taking Rudolf Carnap (1891--1970) as an exemplar of a scholar whose work in philosophy of science was at bottom motivated by the ideal of a unified conception of science, it attempts to distillate the essential characteristics and methodological significance of such a conception by a combination of historical and systematic analysis. Given the conspicuously holoscopic character of Carnap's philosophical orientation, there arises an interesting question about the relation of his work to that of other prominent ``seekers of the wider view'' in the history of philosophy (and history of science). On a more general level, we ask what kind of intellectual and moral characteristics are associated with a scholar who is motivated by the unification of science. Making it explicit: if a coherent conception of a unified conception of science is conceivable, what kind of normative criteria can then be applied to a scholar and his actions? In other words, what are the external and internal qualifications of scholar's vocation under the unified conception of science? In the first part of the dissertation we provide a general account of the problem's background in the intersection of intellectual history and systematics. In the first chapter main emphasis will be put to the dialectic between agent-based and structural explanations in historiography. The survey of a few exemplars of models of historical explanation is intended to provide a background framework for discussing the relation between descriptive analysis and analysis of values. In as much as our modern scientific world conception and the general, essentially human, consciousness of the domain of validity seem to be in a fundamental conflict, a philosophical clarification of the issues that depend on this fundamental distinction is contingent on having proper tools at its disposal. Indeed, it is necessary to acknowledge -- with respect to both scientific knowledge and moral positions -- that the issues of genesis and validity have little in common. Both the image of nature, built upon the masses of scientific and technological knowledge gathered, and the modern conceptions of the moral have developed in the course of history. The lesson that historicism can teach us is the possibility to adopt a symmetrical attitude with respect to the status of the questions of genesis and validity within these (very different) domains. This symmetric attitude enables us to see that the validity of a theory or position (in science or in moral philosophy) cannot depend on the diachronic aspects of its genesis. Rather, it is precisely the case that the late appearance of certain scientific theories and certain moral positions is an index that they are complex and presuppose a great deal genetically, and this is seen to be a common feature of all good theories. Thus, in order to approach the evolution of these ideas from a general perspective, we have to acknowledge their fundamental ontological difference and adopt a variety of tools to study these domains. I present four different approaches to the study of historical phenomena that appertain to the themes of this dissertation. In the second chapter we provide a synopsis of the important thematic about the relationship between morals and science. After a brief examination of the concepts of the moral and the scientific, we proceed to give an account of the concept of scientific self which acts as a kind of normative meta-concept co-ordinating the interaction between the epistemic and the ethical requirements appertaining to the education and professional formation of a scientist. From a historical perspective it is easy to to see that the intension of the concept of scientific self varies according to the contingent factors such as the external conditions of education and the requirements set by new experimental techniques, but the essential, axiologically relevant, internal determinates of the concept are seen to accumulate over time in a conservative manner. Especially interesting here are the determinates that can be traced back to the complementary intellectual traditions of Enlightenment and Romanticism. One of the most important exemplifications of an articulated conception of scientific self can be found in J. G. Fichte's ``Vorlesungen über die Bestimmung des Gelehrten'' of 1794. In these lectures Fichte develops a beautiful -- and still highly relevant -- conception of the true goals of a scholar as well as the qualifications he must fulfill to attain those goals. From Fichte we turn to study the history of one particular intellectual virtue that has direct relevance for the questions tackled in the second part of the dissertation, viz. tolerance. In the third chapter we focus on the importance of a priori knowledge for both ethics and science. These themes are developed only in their barest outlines in order to provide some theoretical support to the fundamental philosophical thesis of the dissertation concerning the distinction between Is and Ought, and its relevance for the question of the unity of science. We will briefly touch upon the question about the relationship of a priori and empirical knowledge in ethics, and provide a brief synopsis of the relevance of the distinction analytic/synthetic in this domain. Finally we address cursorily the ontologically crucial problem about the moral element in man and present -- with a view to the Enlightenment virtues -- a synopsis of the process of the dissociation of the concept of the moral from the concept of the scientific. We describe the characteristics of ethical impulse in modern times and the quite idiosyncratic view on morals and especially on moral justification advocated by the members of Vienna Circle. We will see how the dissociation of the moral from the domain of the rational discourse inevitably results in the philosophically poverished stance of moral non-cognitivism which Carnap maintained throughout his career. In the second part of the dissertation we can finally address the adduced problem in its particular ramifications in the philosophy of Rudolf Carnap. Given this general problematic, we attempt to vindicate the underlying overall motivation of Carnap's philosophy and to reconstruct the architectonic of Carnap's systematic thought in the light of recent research. One of the main tasks is to evaluate the coherence of interpretations provided in the research literature which place Carnap in the continuum of thinkers that are, in some sense, committed to the ideals and values of Enlightenment. The most explicit rendering of this line of thought is the recent monograph, Carnap and Twentieth-Century Thought, by A.W. Carus which puts Carnap's method of explication on center stage. I critically examine this line of interpretation indicated by Carus and explore more deeply its historical dimensions. Over and above the interpretation of Carus, we assess to what extent Carnap's philosophical program fulfills the criteria that are imposed upon it by the requirement of an Enlightenment conception of unified science. The central significance of logic and mathematics in Carnap's philosophical program is seen to derive from the fundamental conception of Carnap that within the total system of knowledge logic and mathematics are performing the essential role of supplying the forms of concepts, statements, and inferences, forms which are then applicable everywhere, hence also to non-logical knowledge. Therefore, the demarcation between logical and non-logical expressions, along with the Principle of Tolerance and logical pluralism, constitutes one of the central strands of Carnap's thought. Indeed, the Principle of Tolerance and the logicality criterion are seen to be two inextricably entwined aspects of a solution to a fundamental problem that Carnap searches a solution to and which characterizes his aspirations throughout the period under consideration here, i.e. the problem of the rationality of scientific discourse under the variability of linguistic systems of knowledge representation. I depict the overall development of Carnap's philosophy with this central idea continually in focus. As a supplement to the interpretation of Carnap's program as a concerted attempt to look for the fundamental invariants of thought and experience, I provide the view that a necessary condition for implementing his ideal of explication is a coherent formulation of what might be called the task of providing genealogies of important scientific concepts and ideas. This complies with the attractive account represented by Howard Stein about the two basic functions of philosophy, i.e., a distinction between ``the enterprise of knowledge'' and the ``enterprise of understanding''. It is argued here that an essential ingredient of Carnap's method of explication is a variety of philosophical history of science which provides the necessary insight into the problem complex one is tackling with under the purview of explication. Therefore, a significant role is bestowed upon historical knowledge and historiography. I attempt to accommodate this aspect of the ``enterprise of understanding'' within the more explicitly confined ``enterprise of knowledge'' that Carnap was overtly concerned with. However, it is argued that the ``enterprise of understanding'' constituted an equally important aspect of Carnap's philosophical program, although it remained covert in his publications.
  • Soinne, Lauri (Helsingin yliopisto, 2009)
    Carotid atherosclerotic disease is a major cause of stroke, but it may remain clinically asymptomatic. The factors that turn the asymptomatic plaque into a symptomatic one are not fully understood, neither are the subtle effects that a high-grade carotid stenosis may have on the brain. The purpose of this study was to evaluate brain microcirculation, diffusion, and cognitive performance in patients with a high-grade stenosis in carotid artery, clinically either symptomatic or asymptomatic, undergoing carotid endarterectomy (CEA). We wanted to find out whether the stenoses are associated with diffusion or perfusion abnormalities of the brain or variation in the cognitive functioning of the patients, and to what extent the potential findings are affected by CEA, and compare the clinically symptomatic and asymptomatic subjects as well as strictly healthy controls. Coagulation and fibrinolytic parameters were compared with the rate microembolic signals (MES) in transcranial Doppler (TCD) and the macroscopic appearance of stenosing plaques in surgery. Patients (n=92) underwent CEA within the study. Blood samples pertaining to coagulation and fibrinolysis were collected before CEA, and the subjects underwent repeated TCD monitoring for MES. A subpopulation (n= 46) underwent MR imaging and repeated neuropsychological examination (preoperative, as well 4 and 100 days after CEA). In MRI, the average apparent diffusion coefficients were higher in the ipsilateral white matter (WM), and altough the interhemispheric difference was abolished by CEA, the levels remained higher than in controls. Symptomatic stenoses were associated with more sluggish perfusion especially in WM, and lower pulsatility of flow in TCD. All patients had poorer cognitive performance than healthy controls. Cognitive functions improved as expected by learning effect despite transient postoperative worsening in a few subjects. Improvement was greater in patients with deepest hypoperfusion, primarily in executive functions. Symptomatic stenoses were associated with higher hematocrit and tissue plasminogen activator antigen levels, as well as higher rate of MES and ulcerated plaques, and better postoperative improvement of vasoreactivity and pulsatility. In light of the findings, carotid stenosis is associated with differences in brain diffusion, perfusion, and cognition. The effect on diffusion in the ipsilateral WM, partially reversible by CEA, may be associated with WM degeneration. Asymptomatic and symptomatic subpopulations differ from each other in terms of hemodynamic adaptation and in their vascular physiological response to removal of stenosis. Although CEA may be associated with a transient cognitive decline, a true improvement of cognitive performance by CEA is possible in patients with the most pronounced perfusion deficits. Mediators of fibrinolysis and unfavourable hemorheology may contribute to the development of a symptomatic disease in patients with a high-grade stenosis.
  • Vikatmaa, Pirkka (Helsingin yliopisto, 2011)
    According to a large body of evidence, carotid endarterectomy (CEA) can prevent strokes, provided that appropriate inclusion criteria and high-quality perioperative treatment methods are utilised with low complication rates. From the patient s perspective, it is of paramount importance that the operation is as safe and effective as possible. From the community s point of view, it is important that CEA provision prevents as many strokes as possible. In order to define the stroke preventing potential of CEA in different communities, a comparison between eight European countries and Australia was performed including 53 077 carotid interventions. A more detailed evaluation was performed in Finland, the United Kingdom and Egypt. It could be estimated that many potentially preventable strokes occur due to insufficient diagnostics and CEA provision. The number of CEAs should be at least doubled in the Helsinki region. The theoretical power of CEA provision in stroke prevention varied significantly between the countries. Delay from symptom to surgery has been identified as one of the most important factors influencing the effectiveness of CEA. In 2008 only 11% of CEAs in Helsinki university central hospital (HUCH) were performed within the recommended14 days. Registered data of 673 CEAs in HUCH during 2000-2005 was analyzed. There was no systematic error that would have changed the outcome analysis. However it is important that registers are audited regularly and cross matching of different registries is possible. A previously unpublished method of combining medial mandibulotomy, neck incision and carotid artery interposition was carried out as a collaboration of maxillofacial, ear, nose and throat and vascular surgeons. Five patients were operated on with a technique that was feasible and possible to perform with little morbidity, but due to the significant risks involved, this technique should be reserved for carefully selected cases. In stroke prevention, organisational decisions seem far more important than details in interventional procedures when CEA is performed with low complication rates, as was the case in the present study. A TIA clinic approach with close co-operation between the on-call vascular surgeons, neurologists and radiologists should be available at all centres treating these patients. Patients should have a direct and fast admission to the hospital performing CEA.
  • Sulin, Zackris (1903)
  • Zhou, Binling (2014)
    This thesis is going to do a comparative study of the Nordic Maritime Codes, Chinese Maritime Code and Rotterdam Rules (United Nations Convention on Contract for the International Carriage of Goods Wholly or Partly by Sea) with respect to carrier’s obligations and liabilities imposed hereupon. The backgrounds for this study are the ambitious goals and controversial future of the Rotterdam Rules, the significant roles that the Nordic countries and China have played in international carriage of goods by sea, and the important position of the carrier’s mandatory obligations and liabilities in this field. Through the comparative study, this thesis tries to disclose the similarities and differences between these legal regimes, to see what changes will be brought to the Nordic/Chinese maritime laws and what impact may be led to their shipping industries if they finally accept the Rotterdam Rules. Based on these backgrounds, the detail contents discussed in this thesis include: (1) the legislative history and scope of application; (2) period of carrier’s responsibility; (3) carrier’s obligations; (4) carrier’s liability for physical loss of or damage to the goods; (5) carrier’s liability for delay in delivery; (6) carrier’s liabilities for deviation, deck cargo and live animals. Each of the NMCs, CMC and the Rotterdam Rules is respectively discussed in detail under each part. By comparing the regional solutions and the new international Convention, at the end of this thesis the possible future of the Rotterdam Rules is discussed from Nordic and Chinese perspectives of views.
  • Lönnberg, Stefan (Helsingin yliopisto, 2012)
    The aim of this study was to evaluate the performance and age-specific effectiveness of cervical cancer screening, by focusing on audit studies of the Finnish cervical cancer screening programme within case control designs with information on the outcome of screening. The study also developed further quality assurance protocols for integration into the programme. The coverage and accuracy of diagnostic data in the screening register were evaluated via individual linkage to two other health care registers. Precancerous and cancerous lesions arising in the screened population were used in an audit of cytology wherein screening-test validity in programme service laboratories was evaluated with a focus on sensitivity failures in the form of false negative screening results. Outcome measures were also related to cross-sectional performance indicators, and variations between laboratories were explored. The mode of detection and screening history was determined for every cervical cancer case and cervical cancer death in Finland in 2000 - 2009. Population-based controls were used in estimation of the age-specific effectiveness of the organised programme in a case control design. We were also able to perform age-specific self-selection bias corrections of the effectiveness estimates. The quality of the screening and cancer registers is such that reliable monitoring and also individual case audits are possible. We found that some analytical failures as measured in terms of false-negative rates of case smears do occur in the programme but that their impact on cancer incidence is small. However, the reproducibility of the cytodiagnosis and variations in the specificity of the screening laboratories should be addressed by means of cytology audits and feedback to the screeners. A large proportion of the cervical cancers and most deaths from cervical cancer occur at ages above the currently recommended invitational ages. Only a very small proportion of the burden arises before first invitation. Non-attenders contribute significantly to incidence and mortality, and a smaller proportion of cases can be attributed to screening failures. Management of screening positives appears to be excellent. The effectiveness of screening, as measured by the reduction in the risk of cervical cancer and death from cervical cancer associated with participation in organised screening, was strongly dependent on age. Screening at ages below 40 and, especially, below 30 was associated with a clearly smaller risk reduction than screening at 40 and above. Also the duration of the protective effect was age-dependent. Most cancers and cancer deaths currently occur because of a lack of screening, and not because of low quality of the screening test or management process. Monitoring and audits of the screening programme are clearly important for the programme s development and further optimisation.
  • Snellman, Marja (2007)
    Avohoitokeuhkokuume on vakava sairaus ja yleinen kuolinsyy maailmanlaajuisesti erityisesti ikääntyneiden keskuudessa. Suomessa sen arvioidaan aiheuttavan vuosittain yli 2000 kuolemantapausta yli 65-vuotiaissa. Keuhkokuumeen yleisimpänä taudinaiheuttajana pidetään on Streptococcus pneumoniae -bakteeria, pneumokokkia. Keuhkokuumeen mikrobietiologian selvittäminen on hankalaa, sillä täydellistä kultaista standardia -diagnostista testiä, joka ei anna vääriä positiivisia tai negatiivisia tuloksia- ei ole olemassa. Kansanterveyslaitos on aloittanut keuhkokuumetutkimuksen, jossa pyritään selvittämään keuhkokuumeen yleisyyttä ja aiheuttajia ikäihmisten parissa. Erityisen kiinnostuksen kohteena on pneumokokkibakteerin osuus taudinaiheuttajana. Tutkimukseen osallistuvilta potilailta kerätään yskös- , virtsa-, nenänielu sekä verinäytteitä, jotka analysoidaan käyttäen erilaisia mikrobiologisia menetelmiä. Yksi tutkimuksen päätavoitteista on muodostaa pneumokokkikeuhkokuumeen tapausmäärittely. Tätä varten tarvitaan tietoa tutkimuksessa suoritettujen diagnostisten testien sensitiivisyyksistä ja spesifisyyksistä. Kultaisen standardin puuttuessa testien sensitiivisyyksien ja spesifisyyksien estimointi ei onnistu tavanomaisin menetelmin, sillä tutkittavien yksilöiden todellinen taudin tila on tuntematon. Tässä tutkielmassa käsitellään latentin luokan analyysia diagnostisten testien luotettavuuden ja pneumokokkikeuhkokuumeen prevalenssin arvioimisessa, kun kultainen standardi puuttuu. Menetelmää sovelletaan Kansanterveyslaitoksen keuhkokuumetutkimuksessa kerättyyn aineistoon. Menetelmään liittyvän teorian lisäksi tutkielmassa esitellään estimointia varten R-ohjelmalle kirjoittamani funktio. Tärkeimpiä lähteitä ovat: Agresti, Alan 2002: Categorical Data Analysis. Wiley. New York. Hagenaars, Jacques A. 1990: Categorical Longitudinal Data. Sage Publication. London Formann, A. - Kohlmann, T. 1996: Latent class analysis in medical research. Statistical Methods in Medical Research, 5, 179-211.
  • Snellman, Marja (2007)
    Community-acquired pneumonia (CAP) is a severe disease and a major cause of death worldwide especially among the elderly. The most common causative pathogen is Streptococcus pneumoniae, pneumococcus. The diagnosis of pneumococcal pneumonia is difficult because there is no gold standard, a diagnostic test that would identify all cases and yet be definite. National Public Health Institute has launched a Finnish Community-Acquired Pneumonia study investigating the frequency and causes of CAP among the elderly aged 65 years and above. Sputum, urine, blood and nasopharyngeal swab samples are the collected from the subjects enrolled in the study and a large number of microbiological assays are performed on samples. One of the main objectives is to find a case definition for pneumococcal pneumonia in the elderly. For this purpose, the accuracy of diagnostic tests performed in the study need to be evaluated. In the absence of gold standard, the true disease status of the subjects is latent and the sensitivities and the specificities of the tests cannot be estimated using conventional methods. The aim of this thesis is to to estimate the sensitivities and the specificities of diagnostic tests and estimate the prevalence of pneumococcal pneumonia among the elderly population in Finland using latent class analysis. The method is applied to data collected in the Finnish Community-Acquired Pneumonia study. Methodological issues in latent class analysis are discussed. In addition, a function for estimating the model parameters using statistical program R is presented. The main sources are: Agresti, Alan 2002: Categorical Data Analysis. Wiley. New York. Hagenaars, Jacques A. 1990: Categorical Longitudinal Data. Sage Publication. London Formann, A. - Kohlmann, T. 1996: Latent class analysis in medical research. Statistical Methods in Medical Research, 5, 179-211.
  • Paukkonen, Heli (2013)
    Casein based formulations are promising materials for controlled drug release. Caseins are the major milk proteins, and their biocompatibility, low toxicity and natural metabolism in physiological systems make caseins extremely suitable materials for pharmaceutical formulations. Polyelectrolyte complex nanoparticles can be prepared under very mild conditions, and they are stable in the gastrointestinal tract, which makes them suitable carrier materials for oral delivery and controlled release of peptide and protein drugs. Aim of this work was to synthesize casein-poly(acrylic acid) polyelectrolyte complex nanoparticles in different mass ratios, and to study the release profile of a model compound rhodamine 6G from these nanoparticles. The casein shell of the nanoparticles was crosslinked with two different crosslinkers, because the objective was to study the effect of surface modification on size of nanoparticles as well as on the release profile of the model compound. The goal was to achieve controlled release of the model compound by modifying the thickness and the density of the casein shell structure. Size and size distribution of nanoparticles was studied by dynamic light scattering. Surface charge was studied by electrophoretic mobility measurements. Morphology was characterized with electron microscopy, and the effect of the casein shell thickness on the release of rhodamine 6G was studied with dialysis method. The synthesized nanoparticles had spherical morphology, but the size distribution was wide. The release of rhodamine 6G was slower from the nanoparticles when compared to the release of reference free rhodamine 6G, but the effect of casein shell thickness on the release of loaded rhodamine 6G remained partially unclear. However, it seems possible to achieve controlled release of encapsulated compounds from casein-poly(acrylic acid) nanoparticles with optimal surface modification in the future.
  • Niemelä, Eeva-Leena (2013)
    Tutkielman tarkoituksena on cash pooling –järjestelmien arvioiminen osakeyhtiölain näkökulmasta ja sen selvittäminen, mitä vaatimuksia osakeyhtiölain säännökset asettavat cash pooling –järjestelmille, miten järjestelmät tulisi lainmukaisesti toteuttaa ja mitä seuraamuksia aiheutuu, jos cash pooling –järjestelmät rikkovat osakeyhtiölain säännöksiä. Cash pooling –järjestelmät ovat yleisesti käytössä oleva tapa järjestää konsernin sisäinen kassanhallinta. Osakeyhtiölain näkökulmasta cash pooling –järjestelmissä on käytännössä kyse konsernin sisäisistä velka- ja saamissuhteista, joita arvioidaan yhtiöoikeudellisesti lähipiirilainoina. Lisäksi cash pooling –järjestelmien yhteydessä annetaan usein lähipiirivakuuksia. Lähipiirilainojen ja -vakuuksien laillisuutta osakeyhtiölain näkökulmasta arvioidaan ensisijaisesti yleisten yhtiöoikeudellisten periaatteiden perusteella. Cash pooling –järjestelmien näkökulmasta keskeisimpiä periaatteita ovat OYL 1:5:n yhtiön toiminnan tarkoitus, OYL 1:7:n yhdenvertaisuusperiaate sekä OYL 1:8:n johdon huolellisuusvelvollisuus. Lähipiirilainan ja –vakuuden antamiseen soveltuu myös OYL 13:1.3:n laittoman varojenjaon kielto, joka edellyttää, että lähipiirilainan tai –vakuuden antamiselle on liiketaloudellinen peruste. Cash pooling –järjestelmässä hyväksyttävä liiketaloudellinen peruste voi olla esimerkiksi lähipiirilainan tai –vakuuden antamisesta saatu korkotuotto, vastainen rahoitus, alentuneet pankkikulut tai muu yhtiön saama hyöty. Useimmiten cash pooling –järjestelmät ovat osakeyhtiölain näkökulmasta lähtökohtaisesti ongelmattomia niin kauan, kun kaikki konserniyhtiöt ovat maksukykyisiä. Lähipiirilainan tai –vakuuden antaminen cash pooling –järjestelmän puitteissa on riskialtista erityisesti, jos koko konserni tai joku järjestelmään osallistuvista konserniyhtiöistä on maksuvaikeuksissa. Tällöin cash pooling –järjestelmän sisällä annetut lähipiirilainat tai –vakuudet voivat olla osakeyhtiölain OYL 13:1.3:n perusteella laitonta varojenjakoa sen perusteella, ettei niiden antamiselle ole yhtiön näkökulmasta liiketaloudellista perustetta. Laittoman varojenjaon yhtiöoikeudellisina seuraamuksina voivat tulla kysymykseen oikeustoimen pätemättömyys OYL 6:28:n nojalla, OYL 13:4:n mukainen laittoman varojenjaon palautusvelvollisuus sekä vahingonkorvausvastuun osalta erityisesti yhtiön johtoa koskeva OYL 22:1:n säännös. Lähipiiritransaktioiden kohdalla johdon vahingonkorvausvastuuta on vielä tehostettu OYL 22:1.3:n tuottamusolettamalla.