77 research outputs found
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Modeling Effective Albedo as a Function of Land Cover Type and Snow Type
The Center for Environmental Radioactivity (CERAD) project UV-maps aims to obtain geographically distributed time-series of solar ultraviolet (UV) radiation in Norway. Since UV-measurements are limited to a few monitoring stations, a full representation of the spatial and temporal distribution needs to be based on a ra-diative transfer model (RTM). A key parameter is the regional albedo distribution. The albedo model developed here apply a gridded set of local albedo values to derive the regional, effective albedo at any given point. In Norway there is a UV-monitoring network that has been operating since 1996, delivering almost continual 20-years time series of UV data. We use these stations as our modeling reference points. In our albedo model we use land cover information and snow dispersion data for 11 years. Land cover classifications combined with snow classifications constitute a matrix of albedo values, with one albedo value for each combination of land cover type and snow type, under the hypothesis that the snow albedo is affected by the underlying land type. In this paper, we outline how to determine these albedo parameters by regression analysis, and give examples of calculated albedo values for some combinations of land cover and snow type
Octyl Methoxycinnamate Modulates Gene Expression and Prevents Cyclobutane Pyrimidine Dimer Formation but not Oxidative DNA Damage in UV-Exposed Human Cell Lines
Octyl methoxycinnamate (OMC) is one of the most widely used sunscreen ingredients. To analyze biological effects of OMC, an in vitro approach was used implying ultraviolet (UV) exposure of two human cell lines, a primary skin fibroblast (GM00498) and a breast cancer (MCF-7) cell lines. End points include cell viability assessment, assay of cyclobutane pyrimidine dimers (CPDs) and oxidated DNA lesions using alkaline elution and lesion-specific enzymes, and gene expression analysis of a panel of 17 DNA damage–responsive genes. We observed that OMC provided protection against CPDs, and the degree of protection correlated with the OMC-mediated reduction in UV dose. No such protection was found with respect to oxidative DNA lesions. Upon UV exposure in the presence of OMC, the gene expression studies showed significant differential changes in some of the genes studied and the expression of p53 protein was also changed. For some genes, the change in expression seemed to be delayed in time by OMC. The experimental approach applied in this study, using a panel of 17 genes in an in vitro cellular system together with genotoxicity assays, may be useful in the initial screening of active ingredients in sunscreens
Marking, sightings and behaviour studies of whales in the Barents Sea and at Svalbard in 1974 and 1975
In 1974 and 1975 a total of 188 minke whales (Balaenoptera acutorostrata)and 14
humpback whales (Megaptera novaeangliae) have been marked in the
Barents Sea and at Svalbard. In addition 2 minke whales have been tagged
north of Shetland. Sighted whales in the Barents Sea and at Svalbard include
1069 minke whales, 25 humpback whales, 1 fin whale (Balaenoptera physalus), 2500-3000 white-beaked dolphins (Lagenor albirostris)
about 50 common porpoises (Phocoena phocoena) and l Greenland right
whale (Balaena mysticetus) with calf. Off the coast of Norway 2 humpback
whales,l sperm whale (Physeter catodon), 400-500 killer whales (Orcinus
orca) and 8-10 Sowerbys whales (Mesoplodon bidens) were observed.
Observations made during the cruises suggest that minke whales breath
and are exposed to the air for 3-4 seconds only and that dives may last
for any period between 12 seconds and 10 minutes when they are followed
(not chased) by ships. About 15 per cent of the minke approached the ships
Cell context-specific expression of primary cilia in the human testis and ciliary coordination of Hedgehog signalling in mouse Leydig cells
Primary cilia are sensory organelles that coordinate numerous cellular signalling pathways during development and adulthood. Defects in ciliary assembly or function lead to a series of developmental disorders and diseases commonly referred to as ciliopathies. Still, little is known about the formation and function of primary cilia in the mammalian testis. Here, we characterized primary cilia in adult human testis and report a constitutive expression of cilia in peritubular myoid cells and a dynamic expression of cilia in differentiating Leydig cells. Primary cilia are generally absent from cells of mature seminiferous epithelium, but present in Sertoli cell-only tubules in Klinefelter syndrome testis. Peritubular cells in atrophic testis produce overly long cilia. Furthermore cultures of growth-arrested immature mouse Leydig cells express primary cilia that are enriched in components of Hedgehog signalling, including Smoothened, Patched-1, and GLI2, which are involved in regulating Leydig cell differentiation. Stimulation of Hedgehog signalling increases the localization of Smoothened to the cilium, which is followed by transactivation of the Hedgehog target genes, Gli1 and Ptch1. Our findings provide new information on the spatiotemporal formation of primary cilia in the testis and show that primary cilia in immature Leydig cells mediate Hedgehog signalling
Genetic Determinants of Facial Clefting: Analysis of 357 Candidate Genes Using Two National Cleft Studies from Scandinavia
Facial clefts are common birth defects with a strong genetic component. To identify fetal genetic risk factors for clefting, 1536 SNPs in 357 candidate genes were genotyped in two population-based samples from Scandinavia (Norway: 562 case-parent and 592 control-parent triads; Denmark: 235 case-parent triads).We used two complementary statistical methods, TRIMM and HAPLIN, to look for associations across these two national samples. TRIMM tests for association in each gene by using multi-SNP genotypes from case-parent triads directly without the need to infer haplotypes. HAPLIN on the other hand estimates the full haplotype distribution over a set of SNPs and estimates relative risks associated with each haplotype. For isolated cleft lip with or without cleft palate (I-CL/P), TRIMM and HAPLIN both identified significant associations with IRF6 and ADH1C in both populations, but only HAPLIN found an association with FGF12. For isolated cleft palate (I-CP), TRIMM found associations with ALX3, MKX, and PDGFC in both populations, but only the association with PDGFC was identified by HAPLIN. In addition, HAPLIN identified an association with ETV5 that was not detected by TRIMM.Strong associations with seven genes were replicated in the Scandinavian samples and our approach effectively replicated the strongest previously known association in clefting--with IRF6. Based on two national cleft cohorts of similar ancestry, two robust statistical methods and a large panel of SNPs in the most promising cleft candidate genes to date, this study identified a previously unknown association with clefting for ADH1C and provides additional candidates and analytic approaches to advance the field
Are waiting times for hospital admissions affected by patients' choices and mobility?
Background
Waiting times for elective care have been considered a serious problem in many health care systems. A topic of particular concern has been how administrative boundaries act as barriers to efficient patient flows. In Norway, a policy combining patient's choice of hospital and removal of restriction on referrals was introduced in 2001, thereby creating a nationwide competitive referral system for elective hospital treatment. The article aims to analyse if patient choice and an increased opportunity for geographical mobility has reduced waiting times for individual elective patients.
Methods
A survey conducted among Norwegian somatic patients in 2004 gave information about whether the choice of hospital was made by the individual patient or by others. Survey data was then merged with administrative data on which hospital that actually performed the treatment. The administrative data also gave individual waiting time for hospital admission. Demographics, socio-economic position, and medical need were controlled for to determine the effect of choice and mobility upon waiting time. Several statistical models, including one with instrument variables for choice and mobility, were run.
Results
Patients who had neither chosen hospital individually nor bypassed the local hospital for other reasons faced the longest waiting times. Next were patients who individually had chosen the local hospital, followed by patients who had not made an individual choice, but had bypassed the local hospital for other reasons. Patients who had made a choice to bypass the local hospitals waited on average 11 weeks less than the first group.
Conclusion
The analysis indicates that a policy combining increased opportunity for hospital choice with the removal of rules restricting referrals can reduce waiting times for individual elective patients. Results were robust over different model specifications
Trends and variation in mild disability and functional limitations among older adults in Norway, 1986–2008
An increase in the number of older adults may raise the demand for health and care services, whereas decreasing prevalence of disability and functional limitations among them might counteract this demographic effect. However, the trends in health are inconsistent between studies and countries. In this article, we estimated the trends in mild disability and functional limitations among older Norwegians and analyzed whether they differ between socio-demographic groups. Data were obtained from repeated cross-sectional surveys conducted in 1987, 1991, 1995, 2002, 2005, and 2008, in total 4,036 non-institutionalized persons aged 67 years or older. We analyzed trends using multivariate logistic regression. On average, the age-adjusted trend in functional limitations was −3.3% per year, and in disability 3.4% per year. The risk for functional limitations or disability was elevated for women compared to men, for married compared to non-married, and was inversely associated with educational level The trends were significantly weaker with increasing age for disabilities, whereas none of the trends differed significantly between subgroups of sexes, educational level or marital status. Both functional limitations free and disability-free life expectancy appeared to have increased more than total life expectancy at age 67 during this period. The analysis suggests downward trends in the prevalence of mild disability and functional limitations among older Norwegians between 1987 and 2008 and a compression of lifetime in such health states. The reduced numbers of older people with disability and functional limitations may have restrained the demand for health and care services caused by the increase in the number of older adults
The Sign of the V: Papers in Honour of Sten Vikner
‘The Sign of the V’ is a festschrift in honour of Sten Vikner, written by friends, colleagues, and collaborators, present and past, to celebrate both his 60th birthday and his contribution to the field of linguistics. The papers cover a wide range of topics in theoretical and empirical linguistic research, from phonetics and phonology, through morphology, semantics, and syntax, to pragmatics, as well as language acquisition, second-language learning, language processing, language teaching, language contact, historical linguistics, and language variation and change. Many different languages are featured, including the Scandinavian languages (i.e. Danish, Faroese, Icelandic, Norwegian and Swedish), Catalan, Dutch, English, Finnish, West Flemish, French, German, Greek, Italian, Scots, and Yiddish. The scope and depth of the chapters in this anthology is a clear indication of the scope and depth of Sten Vikner’s own comparative research well as his impact on the field of linguistics.‘The Sign of the V’ is a festschrift in honour of Sten Vikner, written by friends, colleagues, and collaborators, present and past, to celebrate both his 60th birthday and his contribution to the field of linguistics. The papers cover a wide range of topics in theoretical and empirical linguistic research, from phonetics and phonology, through morphology, semantics, and syntax, to pragmatics, as well as language acquisition, second-language learning, language processing, language teaching, language contact, historical linguistics, and language variation and change. Many different languages are featured, including the Scandinavian languages (i.e. Danish, Faroese, Icelandic, Norwegian and Swedish), Catalan, Dutch, English, Finnish, West Flemish, French, German, Greek, Italian, Scots, and Yiddish. The scope and depth of the chapters in this anthology is a clear indication of the scope and depth of Sten Vikner’s own comparative research well as his impact on the field of linguistics
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