Reliable determination of training-induced alterations in muscle fiber composition in human skeletal muscle using quantitative polymerase chain reaction.

Determination of muscle fiber composition in human skeletal muscle biopsies is often performed using immunohistochemistry, a method that tends to be both time consuming, technically challenging, and complicated by limited availability of tissue. Here, we introduce quantitative reverse transcriptase polymerase chain reaction (qRT-PCR)-based Gene-family profiling (GeneFam) of myosin heavy chain (MyHC) mRNA expression as a high-throughput, sensitive, and reliable alternative. We show that GeneFam and immunohistochemistry result in similar disclosures of alterations in muscle fiber composition in biopsies from musculus vastus lateralis and musculus biceps brachii of previously untrained young women after 12 weeks of progressive strength training. The adaptations were evident as (a) consistent increases in MyHC2A abundance; (b) consistent decreases in MyHC2X abundance; and (c) consistently stable MyHC1 abundance, and were not found using traditional reference gene-based qRT-PCR analyses. Furthermore, muscle fiber composition found using each of the two approaches was correlated with each other (r = 0.50, 0.74, and 0.78 for MyHC1, A, and X, respectively), suggesting that GeneFam may be suitable for ranking of individual muscle phenotype, particularly for MyHC2 fibers. In summary, GeneFam of MyHC mRNA resulted in reliable assessment of alterations in muscle fiber composition in skeletal muscle of previously untrained women after 12 weeks of strength training.

Irisin and FNDC5: effects of 12-week strength training, and relations to muscle phenotype and body mass composition in untrained women.

PURPOSE: To investigate the effects of strength training on abundances of irisin-related biomarkers in skeletal muscle and blood of untrained young women, and their associations with body mass composition, muscle phenotype and levels of thyroid hormones. METHODS: Eighteen untrained women performed 12 weeks of progressive whole-body heavy strength training, with measurement of strength, body composition, expression of irisin-related genes (FNDC5 and PGC1α) in two different skeletal muscles, and levels of serum-irisin and -thyroid hormones, before and after the training intervention. RESULTS: The strength training intervention did not result in changes in serum-irisin or muscle FNDC5 expression, despite considerable effects on strength, lean body mass (LBM) and skeletal muscle phenotype. Our data indicate that training affects irisin biology in a LBM-dependent manner. However, no association was found between steady-state serum-irisin or training-associated changes in serum-irisin and alterations in body composition. FNDC5 expression was higher in m.Biceps brachii than in m.Vastus lateralis, with individual expression levels being closely correlated, suggesting a systemic mode of transcriptional regulation. In pre-biopsies, FNDC5 expression was correlated with proportions of aerobic muscle fibers, a relationship that disappeared in post-biopsies. No association was found between serum-thyroid hormones and FNDC5 expression or serum-irisin. CONCLUSION: No evidence was found for an effect of strength training on irisin biology in untrained women, though indications were found for a complex interrelationship between irisin, body mass composition and muscle phenotype. FNDC5 expression was closely associated with muscle fiber composition in untrained muscle.

Model-derived dose rates per unit concentration of radon in air in a generic plant geometry.

A model for the derivation of dose rates per unit radon concentration in plants was developed in line with the activities of a Task Group of the International Commission on Radiological Protection (ICRP), aimed at developing more realistic dosimetry for non-human biota. The model considers interception of the unattached and attached fractions of the airborne radon daughters by plant stomata, diffusion of radon gas through stomata, permeation through the plant's epidermis and translocation of deposited activity to plant interior. The endpoint of the model is the derivation of dose conversion coefficients relative to radon gas concentration at ground level. The model predicts that the main contributor to dose is deposition of (214)Po α-activity on the plant surface and that diffusion of radon daughters through the stomata is of relatively minor importance; hence, daily variations have a small effect on total dose.

The relationship of retinal vessel diameter to changes in diabetic nephropathy structural variables in patients with type 1 diabetes.

AIMS/HYPOTHESIS: We examined whether retinal vessel diameter in persons with type 1 diabetes mellitus is associated with changes in subclinical anatomical and functional indicators of diabetic nephropathy. METHODS: Persons with type 1 diabetes mellitus had gradable fundus photographs and renal biopsy data at baseline and 5-year follow-up (n = 234). Retinal arteriolar and venular diameters were measured at baseline and follow-up. Central retinal arteriole equivalent (CRAE) and central retinal venule equivalent (CRVE) were computed. Baseline and 5-year follow-up renal structural variables were assessed by masked electron microscopic morphometric analyses from percutaneous renal biopsy specimens. Variables assessed included: mesangial fractional volume, glomerular basement membrane width, mesangial matrix fractional volume and glomerular basement membrane width composite glomerulopathy index. RESULTS: While controlling for other covariates, baseline CRAE was positively associated with change in the glomerulopathy index over the 5-year period. Change in CRAE was inversely related to a change in mesangial matrix fractional volume and abnormal mesangial matrix fractional volume, while change in CRVE was directly related to change in the volume fraction of cortex that was interstitium [Vv((Int/cortex))] over the 5-year period. Baseline CRAE or CRVE or changes in these diameters were not related to changes in other anatomical or functional renal endpoints. CONCLUSIONS/INTERPRETATION: Independently of other factors, baseline CRAE correlated with changes in glomerulopathy index, a composite measure of extracellular matrix accumulation in the mesangium and glomerular basement membrane. A narrowing of the CRAE was related to mesangial matrix accumulation. Changes in CRVE were related to changes in Vv((Int/cortex),) a measure of interstitial expansion in persons with type 1 diabetes mellitus.

A population-based evaluation of the seventh edition of the TNM system for lung cancer.

Our study describes the new seventh edition of the TNM system for lung cancer in a national population and its clinical implications. We classified 1,885 operated patients with lung cancer, reported to the Cancer Registry of Norway (Oslo, Norway) from 2001 to 2005, according to the sixth and the seventh edition of the TNM system. We compared survival differences adjusting for known prognostic factors. Furthermore, we evaluated the overall predictive ability of both editions using Harrell's concordance index. Survival curves by stage for each of the editions were similar; however, a better description of stage IIIB was observed in the seventh edition. Survival rates of T1b and T2a tumours were similar (log rank p = 0.94). The concordance index was 0.68 for both editions, indicating no overall difference in their predictive accuracy. In the seventh edition, 211 (29%) stage IB patients migrated to stage II and 161 (48%) patients migrated from stage IIB to IIA. Stage migrations could change the treatment for up to 326 (17.3%) of the study patients. The seventh edition did not improve the overall predictive ability of the TNM system; however, the new classification implies changes in treatment for nearly one-fifth of the cases. The implications of the seventh TNM edition for the outcomes of patients should be studied further.

Effectiveness of third-generation chemotherapy on the survival of patients with advanced non-small cell lung cancer in Norway: a national study.

BACKGROUND: To investigate whether the introduction of modern third-generation chemotherapy was associated with survival benefits in a national population of patients with advanced non-small cell lung cancer (ANSCLC) and to explore geographical and temporary variations in the utilisation of chemotherapy. METHODS: All patients with ANSCLC in the Cancer Registry of Norway during 1994-2005 were included. Using sales of vinorelbine as an indicator for chemotherapy, annual county utilisation rates were calculated. Survival before and after the general introduction of vinorelbine and associations between survival and variations in utilisation in counties were investigated. In a subgroup, the predictors of having received chemotherapy were explored. RESULTS: Of 24 875 registered patients with lung cancer, 13 757 had ANSCLC. The annual utilisation of the indicator drug in Norway increased from 3.7 to 184.2 g (1998-2005). Median survival increased from 149 to176 days (p<0.001). The adjusted hazard ratio (HR) for a diagnosis after the introduction was 0.93 (95% CI 0.88 to 0.99). County utilisation rates of vinorelbine (increments of 100 mg/1000 inhabitants) were inversely associated with the risk of death (HR 0.84, 95% CI 0.73 to 0.98). County of residence predicted chemotherapy utilisation with odds ratios in the range 0.13 (95% CI 0.1 to 0.19) to 1.04 (95% CI 0.64 to 1.69), a county with traditionally high utilisation as reference. CONCLUSION: Utilisation of third-generation chemotherapy was associated with slightly increased survival of patients with ANSCLC. Geographical and temporal differences in utilisation indicate variable quality of delivered care.

Caring for patients with spinal metastasis during an MRI examination.

INTRODUCTION: Magnetic resonance imaging (MRI) is without question the best tool used for diagnosing and evaluating spinal metastasis. An MRI examination is known to be of great value for the treatment planning and survival of these patients. Radiographers have an important role in how the quality of care is experienced by the patients during an MRI examination. The purpose of the study was to describe the radiographers' perceptions of caring for patients with spinal metastasis during an examination with MRI. METHODS: Phenomenography was used to analyze the data in this study. Ten radiographers, one male and nine females were interviewed about their perception of caring for patients with spinal metastasis during an MRI examination. RESULTS: The findings showed that the radiographers' caring perspective influenced their approach towards what they consider to be essential in the care of patients with spinal metastasis. This can impact the extent of the adjustment to the care needs of the patients. Furthermore, the findings showed that there was a strong connection between the radiographers' care approach and preparedness to personalize the care. CONCLUSION: This study shows that it is important to be flexible when providing care for the patients. A person-centered care is achieved when the caring perspective is based on the patient's view and adjustments are made in agreement with the patient.

Prevalence of iron deficiency and anemia among healthy women of reproductive age in Bhaktapur, Nepal.

OBJECTIVE: To determine the prevalence of anemia and iron status as assessed by biochemical markers and to explore the associations between markers of iron status and iron intake. STUDY AREA AND POPULATION: Five hundred healthy women of reproductive age from the Bhaktapur district of Nepal were included in the study. METHODS: A cluster sampling procedure was applied for this cross-sectional study. Women without any ongoing infection aged 13-35 years were selected randomly from the population. We measured the plasma concentration of hemoglobin (Hb), ferritin and transferrin receptors. Dietary information was obtained by a food frequency questionnaire and two 24-h dietary recalls. RESULTS: The prevalence of anemia (Hb concentration <12 g/dl) was 12% (n=58). The prevalence of depleted iron stores (plasma ferritin <15 microg/l) was 20% (n=98) whereas the prevalence of iron deficiency anemia (anemia, depleted iron stores with elevated transferrin receptor i.e. >1.54 mg/l) was 6% (n=30). Seven percent (n=35) of women were having iron-deficient erythropoiesis (depleted iron stores and elevated transferrin receptor but normal Hb). Out of the 58 anemic women, 41 (71%) and 31 (53%) were also having elevated plasma transferrin receptor and depleted iron stores, respectively. Fifty-four percent of the women ate less than the recommended average intake of iron. The main foods contributing to dietary iron were rice, wheat flour and green and dry vegetables. CONCLUSIONS: The prevalence of anemia in our study was substantially lower than the national figure for non-pregnant women. Only about half of the women with anemia were also having depleted iron stores, suggesting that other causes of anemia may be prevalent in this population. SPONSORSHIP: Norwegian Universities Committee for Development, Research and Education (NUFU).

The prevalence of anemia and iron deficiency is more common in breastfed infants than their mothers in Bhaktapur, Nepal.

BACKGROUND/OBJECTIVES: Iron deficiency anemia is a widespread public health problem, particularly in low- and middle-income countries. Maternal iron status around and during pregnancy may influence infant iron status. We examined multiple biomarkers to determine the prevalence of iron deficiency and anemia among breastfed infants and explored its relationship with maternal and infant characteristics in Bhaktapur, Nepal. SUBJECTS/METHODS: In a cross-sectional survey, we randomly selected 500 mother-infant pairs from Bhaktapur municipality. Blood was analyzed for hemoglobin, ferritin, total iron-binding capacity, transferrin receptors and C-reactive protein. RESULTS: The altitude-adjusted prevalence of anemia was 49% among infants 2-6-month-old (hemaglobin (Hb) <10.8 g/dl) and 72% among infants 7-12-month-old (Hb <11.3 g/dl). Iron deficiency anemia, defined as anemia and serum ferritin <20 or <12 µg/l, affected 9 and 26% of infants of these same age groups. Twenty percent of mothers had anemia (Hb <12.3 g/dl), but only one-fifth was explained by depletion of iron stores. Significant predictors of infant iron status and anemia were infant age, sex and duration of exclusive breastfeeding and maternal ferritin concentrations. CONCLUSIONS: Our findings suggest that iron supplementation in pregnancy is likely to have resulted in a low prevalence of postpartum anemia. The higher prevalence of anemia and iron deficiency among breastfed infants compared with their mothers suggests calls for intervention targeting newborns and infants.

A call for specific codes for diabetes foot and eye care.

In this report, we propose new International Classification of Diseases (ICD) codes that could be incorporated into computer-based patient records or administrative data to monitor and improve diabetes care. Neither the ICD, 9th Revision, nor its imminent replacement, the ICD, 10th Revision, has specific codes for foot examinations and funduscopic examinations in the asymptomatic person, high-risk diabetic foot status, or clinically significant macular edema. Adoption of official codes for these procedures and conditions implemented in conjunction with computerized databases could be used for surveillance, program planning, and quality of care assessment. Computerized medical records could use the codes to monitor care and issue reminders to patients and providers. Payors could offer reimbursement incentives to encourage compliance with standard recommendations. These codes for care procedures could be linked to outcomes, such as amputations and blindness, to improve our understanding of the etiology of blindness and the relationship between process and outcome. The uniform adoption of these codes would facilitate comparison between health care systems, geographic regions, and nations. The diabetes community should encourage the National Center for Health Statistics to adopt new codes that could be used to monitor diabetes preventive care practices.

Buffer therapy during out-of-hospital cardiopulmonary resuscitation.

The effects of infusing a buffer solution on resuscitability and outcome was tested in patients during out-of-hospital cardiac arrest. A number (502) of adults with asystole or ventricular fibrillation with failure of first defibrillation attempt were entered into a prospective, randomized, double-blind, controlled trial. Of these, 245 patients received 250 ml of sodium bicarbonate-trometamol- phosphate mixture with buffering capacity 500 mmol/l and 257 patients received 250 ml 0.9% saline. Except for the investigational infusion, all patients were resuscitated according to international guidelines. Eighty-seven patients (36%) receiving buffer were admitted to hospital ICU and 24 (10%) were discharged from hospital alive, vs. 92 (36%) and 35 (14%) receiving saline (95% confidence interval (CI) for difference between groups: -6%-6% for rate of admission and -1%-9% for rate of discharge). Using a logistic regression analysis, ventricular fibrillation as initial rhythm (odds ratio 8.06, CI 3.70-17.56) improved the outcome, whereas buffer therapy had no effect (odds ratio 0.77, CI 0.43-1.41). Mean base excess at hospital admission was -9 after Tribonat vs. -11 after saline (P = 0.04, CI for difference 0.2-3.8). Only 16 of the 502 patients had arterial alkalosis on arrival in the hospital and no patient had a positive base excess. Patients resuscitated after out-of-hospital cardiac arrest had metabolic acidosis, but buffer therapy did not improve the outcome.

Pregnancy outcome in Norway after Chernobyl.

Pregnancy outcome has been studied in terms of legal abortions, early spontaneous abortions and total number of pregnancies (in an ad hoc study covering 6 counties) as well as various perinatal health problems (on the basis of routinely recorded data for epidemiological surveillance from the Medical Birth Registry of Norway). Apparently, no effects were observed in terms of an increased occurrence of legal abortions, while spontaneous abortions increased from 7.2% of all pregnancies during the last 12 months before the accident to 8.3% after the accident [corrected]. At the same time, the total number of pregnancies somewhat decreased. Based on monthly measurements in each municipality of external and internal (food-based) doses, dose-response associations were assessed for a number of perinatal health problems. No associations were observed.

PIP: The effects of Chernobyl on pregnancy outcome were investigated in Norway in terms of legal abortions, early spontaneous abortions, total pregnancies, and perinatal health problems (cataracts, microcephaly, low birth weight, and perinatal mortality). The epidemiological results showed that there were no serious gross changes in pregnancy outcome in Norway after Chernobyl in 1986. Anxiety may have led to the temporary decrease in pregnancies. The statistically significant difference in spontaneous abortions between 19867 and 1987, particularly in the months following Chernobyl, may be related but causation cannot be determined based on the present data; i.e., dietary changes due to anxiety may also be related. Further analyses will be conducted with data spanning 5 years after Chernobyl. The Central Bureau of Statistics provided data on legal abortions as reported by hospitals to county medical officers. Spontaneous abortions (16 weeks) are based on ad hoc notifications from hospitals in 5 counties: Aust-Agder, Hordaland, Oppland, Troms, and Trondelag. Compulsory notification of births is recorded in the Medial birth Registry and includes congenital malformations and other perinatal health problems. The National Institute of Radiation Hygiene recorded data after the accident on indoor gamma rates, radiocesium (Cs 134) soil samples, and municipality specific average food-based dose equivalents of Cs 134 and 137 in meat and meat supplies. The total external and internal dose is provided for May 1986-April 1989. Food-based doses remained at an elevated level for an extended period of time. Infant exposure was considered form the 2nd month of gestation. Legal abortions, induced or spontaneous, were not impacted by Chernobyl, but the effect may have been delayed to the 3rd or 4th quarter with a 1.0% increase. However, at Haukeland Hospital in Bergen, the highest abortion rates were 19.1% in 1985-86 and 19.2% in 1986-87. Pregnancies temporarily decreased in the 3rd and 4th quarters following the accident in a period usually reflecting annual increases. Cataract occurrences increased the year after the accident with 8 observed and 3.8 expected, but the P value was insignificant (P=.74). Microcephaly followed a similar pattern. Birth 2500 gms had observed values of 2726 vs. 2639.2 expected, an insignificant P value of .99. Observed perinatal deaths of 634 were less than the 718.8 expected.

A prospective, randomized study of three operations for acute rupture of the anterior cruciate ligament. Five-year follow-up of one hundred and thirty-one patients.

A five-year, prospective, randomized follow-up study was done to compare three methods for repair of a rupture of the anterior cruciate ligament of the knee; acute primary repair (Group 1), acute repair with a synthetic ligament-augmentation device (Group 2), and acute repair augmented with an autologous bone-patellar ligament-bone graft (Group 3). One hundred and fifty patients who had an acute rupture of the anterior cruciate ligament were randomized to one of the three repair groups, with fifty patients in each group. The patients were between sixteen and fifty years old (mean, twenty-nine years old). All patients had the operation within ten days after the injury. The rehabilitation protocol was identical for each group. The patients were evaluated prospectively at one, two, and five years with use of the Tegner scoring system for level of activity and the scoring system of Lysholm and Gillquist for function, and the stability of the knee was assessed with clinical examination and with use of the KT-1000 arthrometer. One hundred and thirty-one patients completed the study and ten other patients were known to have had a failure of the procedure, a 94 percent rate of follow-up. All three groups had a lower level of activity at the five-year follow-up evaluation than they had had before the injury. The patients who had had augmentation with a patellar-ligament graft had a significantly higher mean level of activity at two years than those who had had non-augmented repair with (p = 0.002) and those who had had repair with a synthetic ligament-augmentation device (p = 0.01). They also had a significantly higher mean level of function at two years than those who had had non-augmented repair (p = 0.0001) and those who had had repair with a synthetic ligament-augmentation device (p = 0.03) and a significant higher mean level of function at five years than those who had had non-augmented repair (p = 0.004). The ability to attain full extension improved significantly in all three groups during the five-year follow-up period; the highest gains occurred in the group that had had augmentation with a patellar-ligament graft. Rotatory and anterior instability progressively increased during the follow-up period for all three groups. At one, two, and five years, the knees that had had repair with a patellar-ligament graft were significantly more stable than those that had had non-augmented repair and those that had had repair with a ligament-augmentation device (p < 0.0001 to p = 0.03). The findings of this study reinforce the conclusions of our two-year follow-up report that a non-augmented primary repair should not be performed, a repair with a ligament-augmentation device has an unacceptably high rate of failure (more than one-third of the patients), and a repair that is augmented with the patellar ligament has the best outcome.

The impact of the Trial Coordinator in the Diabetes Control and Complications Trial (DCCT). The DCCT Research Group.

The Diabetes Control and Complications Trial (DCCT) is a multicenter, randomized clinical trial studying the effects of two different diabetes regimens on the development and progression of early vascular complications in persons with insulin-dependent diabetes mellitus (IDDM). All of the centers have a Trial Coordinator. We administered a self-report questionnaire to each center to document the different activities for which the Trial Coordinator assumed responsibility in successfully orchestrating the trial. All Trial Coordinators were responsible primarily for recruitment, screening, medical management, education and training, and adherence and administration. Although documentation indicated that the Trial Coordinator was responsible for all of the above activities, the original applications reflected that very few of the Principal Investigators anticipated such a wide variety of duties. A Trial Coordinator was named in only 13 of the 21 applications and of these, only 6 actually assumed the position. This study points out the need to develop a means to define characteristics, background, and training appropriate for candidates for a Trial Coordinator position in future studies.

Postoperative pain after anterior cruciate ligament reconstruction using a transligamentous approach.

Anterior cruciate ligament reconstruction by free patellar tendon graft was performed using 2 different surgical approaches to the intercondylar notch in 67 consecutive patients with chronic anterior cruciate ligament insufficiency. In the first 30 patients (Group A), the traditional medial parapatellar arthrotomy with lateral luxation of the patella was done, whereas in the last 37 patients (Group B) a transpatellar tendon approach was used. Postoperative pain was managed by analgesics and, in patients who had epidural anesthesia, by administration of bupivacaine in indwelling catheters. Generally, the analgesics and bupivacaine were given immediately on request to establish comfort at rest and to permit range of motion exercises without severe pain. Compared with those in Group A, the patients of Group B had a significantly longer period from the first dose of analgesic or bupivacaine to the second, and the total number of doses of analgesic or bupivacaine was significantly lower. In the subgroup of patients with epidural anesthesia (21 in Group A and 32 in Group B), the Group B patients required significantly less analgesics, as doses equivalent to 10 mg of morphine, compared with that of Group A.

Epidemiology of anterior cruciate ligament injuries in soccer.

We did a retrospective study of all anterior cruciate ligament injuries (972) verified by arthroscopic evaluation at hospitals in the Hordaland region of Norway from 1982 to 1991. Our final study group comprised 176 patients who had participated in organized soccer and answered a questionnaire. The overall incidence rate was 0.063 injuries per 1000 game hours. Men incurred 75.6% (133) of the injuries. Women had an incidence rate of 0.10 injuries per 1000 game hours, significantly higher than that for men (0.057). The incidence rate was higher (0.41) for men in the top three divisions. Most of the injuries (124) occurred during games. Contact injuries from tackling was the injury mechanism in 46.0% of the cases. Players on the offensive team incurred 122 (69.3%) of the injuries. Reconstructive surgery was performed on 131 (74.4%) of the injured players and was found necessary for return to a high level of play. Half of the players (87) returned to soccer; men at high levels of play had the highest return rate (88.9%), and men over age 34 had the poorest return rate (22.9%). Nearly one-third of the injured athletes gave up soccer because of poor knee function or fear of new injury.

A prospective, randomized study of three surgical techniques for treatment of acute ruptures of the anterior cruciate ligament.

Treatment of ACL tears is controversial. Recent reports on nonoperative treatment have shown poor results. Results after primary repair have deteriorated with time, leading to augmentation procedures that seem to have improved the results. However, there have been few prospective, randomized studies in this field. Our goal was to compare primary repair with a bone-patellar tendon-bone augmentation method and with a new method using the Kennedy Ligament Augmentation Device. One hundred fifty patients aged 16 to 50, all of whom had acute ACL tears, were randomized with the closed envelope method to one of three groups treated with open surgical methods. Fifty patients were treated with primary repair, 50 patients with patellar tendon augmentation, and 50 patients were augmented with the Kennedy Ligament Augmentation Device. All patients were operated on within 10 days of injury. The rehabilitation protocol was identical, consisting of a long leg cast for 2 weeks, followed by a brace with no weight-bearing and limited motion for 6 weeks. The patients were followed prospectively by one surgeon (LE) using the Lysholm functional score, Tegner activity level score, clinical evaluation and KT-1000 arthrometer at 6 months, 1, and 2 years. Three patients were lost to followup. There was no age or activity level difference between the groups. Sport activities led to 85% of the injuries, with skiing, soccer, and European handball representing 80% of injuries. All three groups reduced their activity level the 1st year. The repair group remained at the same level after 2 years.(ABSTRACT TRUNCATED AT 250 WORDS)

Adaptive noise smoothing filter for images with signal-dependent noise.

In this paper, we consider the restoration of images with signal-dependent noise. The filter is noise smoothing and adapts to local changes in image statistics based on a nonstationary mean, nonstationary variance (NMNV) image model. For images degraded by a class of uncorrelated, signal-dependent noise without blur, the adaptive noise smoothing filter becomes a point processor and is similar to Lee's local statistics algorithm [16]. The filter is able to adapt itself to the nonstationary local image statistics in the presence of different types of signal-dependent noise. For multiplicative noise, the adaptive noise smoothing filter is a systematic derivation of Lee's algorithm with some extensions that allow different estimators for the local image variance. The advantage of the derivation is its easy extension to deal with various types of signal-dependent noise. Film-grain and Poisson signal-dependent restoration problems are also considered as examples. All the nonstationary image statistical parameters needed for the filter can be estimated from the noisy image and no a priori information about the original image is required.

The influence of geological factors on indoor radon concentrations in Norway.

Indoor radon levels in 1618 Norwegian dwellings located in different geological settings are compared with geological information. The results show a significant correlation between indoor radon levels and geological factors. Radium content and permeability of the building ground have been found to be useful indicators of indoor radon concentrations. Based on easily accessible geological data, an assessment of the radon potential of an area can be given. Areas of high radon risk in Norway include: (a) exposed bedrock with elevated levels of radium; and (b) highly permeable unconsolidated sediments derived from all rock types and moderately permeable sediments derived from rock types rich in radium. A comparison of indoor radon with house construction characteristics and ventilation habits suggests that radon concentrations in Norwegian dwellings are also influenced by ventilation system, aeration habits and floor level of the room where the measurements were carried out. The significant correlation between indoor radon levels and geological factors observed in the present investigation indicates that it is possible to outline areas of high radon risk in Norway based on geological information.

Radon, fluoride and 62 elements as determined by ICP-MS in 145 Norwegian hard rock groundwater samples.

Hard rock groundwater (145) samples collected from private drinking water wells in the environs of Oslo and Bergen were analysed for their radon and fluoride contents. A further 62 elements were determined by inductively coupled plasma mass spectrometry (ICP-MS). For 59 elements, more than 50% of all concentration values were above the detection limit. Characteristic differences between the Oslo- and Bergen-dataset can be shown to be related to host rock lithology. Variation in element contents generally spans 2-6 orders of magnitude. Concentrations of several elements (e.g. Ba, F, Fe, Mn, Na, Rn) exceed current drinking water action levels in a significant number of cases. High levels of other parameters such as Be, Mo, Th and U, which could have an impact on health, were observed. There are no Norwegian action levels currently defined for these elements. The economic and toxicological impacts of these findings require urgent assessment.