Publications by authors named "Ikonen A"

Geological disposal of radioactive waste has been recognized as the 'reference solution' to ensure the safety required for the present and future society and environment. To study the possible exposure pathways from groundwater to humans, radioactive transport modelling is used. One of the ecosystems that may play a significant role when assessing the dose conversion factor (i.

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The International Atomic Energy Agency has coordinated an international project addressing enhancements of methods for modelling the biosphere in post-closure safety assessments of solid radioactive waste disposal. This has resulted in the enhanced BIOMASS methodology that is described elsewhere in this special issue. To a large degree, the enhancements to the BIOMASS methodology arose from experience gained in applying the original methodology, both in the context of other international projects and in assessments of existing or proposed disposal facilities for solid radioactive wastes.

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The International Atomic Energy Agency has coordinated an international project addressing enhancements of methods for modelling in post-closure safety assessments of solid radioactive waste disposal. The project used earlier published work from the IAEA biosphere modelling and assessment (BIOMASS) project to further develop methods and techniques. The task was supported by a parallel on-going project within the BIOPROTA forum.

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Ongoing national programmes and International forums have in recent decades developed and enhanced methods and strategies in how to address the characterisation of potentially suitable sites for radioactive waste repositories. Siting processes, site selection and site investigation programmes have been conducted for near surface and geological repositories and plans for construction are in progress or have already been implemented. Lessons learned from these national and international programmes are available and results are published.

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An innovative 18 GHz HIISI (Heavy Ion Ion Source Injector) room temperature Electron Cyclotron Resonance (ECR) ion source (ECRIS) has been designed and constructed at the Department of Physics, University of Jyväskylä (JYFL), for the nuclear physics program of the JYFL Accelerator Laboratory. The primary objective of HIISI is to increase the intensities of medium charge states (M/Q ≅ 5) by a factor of 10 in comparison with the JYFL 14 GHz ECRIS and to increase the maximum usable xenon charge state from 35+ to 44+ to serve the space electronics irradiation testing program. HIISI is equipped with a refrigerated permanent magnet hexapole and a noncylindrical plasma chamber to achieve very strong radial magnetic confinement with B = 1.

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Radionuclide transport with groundwater flow and subsequent doses to people are an aspect to be studied when assessing the long-term safety of geological nuclear waste repositories. A scenario where the radionuclide release migrates through a three-layer sediment structure of a lake in a farming environment is presented in this paper. The sediment column consists of deep (till), intermediate (glacio-aquatic sediment) and top layers (clay).

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Non-human biota in radiological risk assessment is typically evaluated using Reference Organisms (ROs) or Reference Animals and Plants (RAPs), for all exposure situations. However, it still remains open whether the use of an increased number of species would improve the ability to demonstrate protectiveness of the environment. In this paper, the representativeness of a broader list of fauna is tested in terms of the geometrical characteristics and habits for radiological risk assessments in the case of routine discharges from a nuclear installation: the Cadarache centre.

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The International Atomic Energy Agency has coordinated an international project addressing climate change and landscape development in post-closure safety assessments of solid radioactive waste disposal. The work has been supported by results of parallel on-going research that has been published in a variety of reports and peer reviewed journal articles. The project is due to be described in detail in a forthcoming IAEA report.

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Objective: To assess if arthroscopic partial meniscectomy (APM) is superior to placebo surgery in the treatment of patients with degenerative tear of the medial meniscus.

Methods: In this multicentre, randomised, participant-blinded and outcome assessor-blinded, placebo-surgery controlled trial, 146 adults, aged 35-65 years, with knee symptoms consistent with degenerative medial meniscus tear and no knee osteoarthritis were randomised to APM or placebo surgery. The primary outcome was the between-group difference in the change from baseline in the Western Ontario Meniscal Evaluation Tool (WOMET) and Lysholm knee scores and knee pain after exercise at 24 months after surgery.

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The assessment processes concerning the safety of nuclear waste repositories include the modelling of radionuclide transport in biosphere and the evaluation of the doses to the most affected humans. In this paper, a scenario, in which a contaminated lake is the water source for drinking water, irrigation water and watering of livestock, is presented. The objective of the paper is to probabilistically study the influence of lake properties as parameters in the assessment scenario.

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Background And Aims: Blunt thoracic injury is a common cause for hospital admission after trauma. The effect of the number of rib fractures on the outcome is controversial. In this study, our hypothesis was that an increasing number of rib fractures correlates with mortality and hospital resource utilization.

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Purpose: Obesity is the most important risk factor for obstructive sleep apnea (OSA); however, the exact underlying mechanisms are still not fully understood. The aim of this study was to examine the morphology of upper airways in overweight habitual snorers and in mild OSA patients. Furthermore, the associations between weight loss, parapharyngeal fat pad area and OSA were assessed in a 1-year randomised, controlled follow-up study originally conducted to determine the effects of lifestyle changes with weight reduction as a treatment of OSA.

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Heat sensitivity is a well-recognised feature in multiple sclerosis (MS). However, little is known about how heat affects physical performance in persons with MS. The objective of the study was to evaluate the effects of short-term heat stress on physical functioning in persons with MS.

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Objectives: The aims of this study were to describe the use of occupational health services and other health care of Finnish employees and to examine associations between health problems and risks, and primary care visits to occupational health nurses and physicians and other health care.

Methods: A nationally representative sample of 3,126 employees aged 30-64 participated in the Health 2000 study, which consisted of a health interview, questionnaires, a clinical health examination, and the Composite International Diagnostic Interview. The use of health services was measured by self-reported visits.

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Background: Heat sensitivity and cognitive deficits are typical manifestations of multiple sclerosis (MS). Although cognitive deficits are quite well characterized, practically no data exist on the effects of heat on cognitive performances in MS.

Objective: To assess the effects of short-term heat stress on cognitive functioning in subjects with MS.

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Introduction: Primary care is frequently integrated in Finnish occupational health services (OHS). This study examines the frequency of work-related health problems in occupational health (OH) physicians' consultations for primary care and associations between health problems and interventions carried out by OH physicians.

Methods: OH physicians assessed the health problems of 651 consecutive visits in a private OHS unit.

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Purpose: The outcome of surgery in patients with temporal lobe epilepsy (TLE) and normal high-resolution magnetic resonance imaging (MRI) has been significantly worse than in patients with unilateral hippocampal damage upon MRI. The purpose of this study was to determine the long-term outcomes of consecutive true MRI-negative TLE patients who all underwent standardized preoperative evaluation with intracranial electroencephalography (EEG) electrodes.

Methods: In this study we present all adult MRI-negative TLE surgery candidates evaluated between January 1990 and December 2006 at Kuopio Epilepsy Center in Kuopio University Hospital, which provides a national center for epilepsy surgery in Finland.

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Urinary proteins and exercise-induced proteinuria have been the subject of much research. Proteinuria has been studied in depth after different running and cycling intensities and durations and the different mechanisms of glomerular filtration and tubular dysfunction have been elucidated. The present study was carried out to compare urinary protein profiles of athletes in different sport categories (endurance sport, team sport, strength sport).

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Background And Aims: The splanchnic circulation has an important function in the body under both physiological and pathophysiological conditions. Despite its importance, no reliable noninvasive procedures for estimating splanchnic circulation have been established. The aim of this study was to evaluate MRI as a tool for assessing intra-abdominal blood flows of the aorta, portal vein (VPO) and the major intestinal and hepatic vessels.

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The title compound, [Zn(C(6)H(5)S)(2)(C(18)H(12)N(2))], was prepared as a model for future complexes that will be incorporated into light-harvesting arrays. The Zn(II) atom lies on a twofold rotation axis and the ligands are arranged tetra-hedrally around this atom. The benzene-thiol-ate ligand and the biquinoline ligand are nearly perpendicular to one another, making a dihedral angle of 84.

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In Finland, a nuclear repository site is situated on the western coast where the current land uplift rate is 6mm/yr. A set of tools has been developed for predicting the future terrain and vegetation types, and for producing estimates of the site-specific parameter values for use in simplified radionuclide transport models. Although the landscape will change considerably within the next millennia, the likely changes are relatively predictable.

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We describe a diagnostic problem in a young adult with a long history of frequently occurring headache episodes. The cause for these episodes was traced to a rare condition, extensive arachnoid cyst of sphenoid sinus. Extensive lesions of the sphenoid sinus are relatively rare and can cause non-specific symptoms.

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The aim of this study was to investigate CT angiography (CTA) luminal area measurements in the assessment of carotid artery stenosis compared with the current clinically used criteria based on lumen diameter measurements. Seventy-two vessels in 36 patients were evaluated by CTA and digital subtraction angiography (DSA). Two observers measured area and diameter stenosis degrees using automated 3D CTA analysis software.

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