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The Global Ozone Monitoring Experiment (GOME) onboard the ERS-2 satellite has been in operation since July 1995. The Norwegian ground-based total ozone network has played an important role both in the main validation during the commissioning phase and in the validation of upgraded versions of the analysis algorithms of the instrument. The ground-based network consists of various spectrometer types (Dobson, Brewer, UV filter instruments). The validation of the second algorithm version used until January 1998 reveals a very good agreement between GOME and ground-based data at solar zenith angles 60°. The deviations strongly depend on the season of the year, being negative in summer and positive in winter/spring, The deviations furthermore show a considerable scattering (up to ±25 DU in monthly average values of 5° SZA intervals), even in close spatial and temporal coincidence with ground-based measurements, especially in the high Arctic. The deviations are also dependent on the viewing geometry/ground pixel size with an additional negative offset for the large pixels used in the backswath mode and at solar zenith angles >85°, compared to forward-swath pixels.Key words. Atmospheric composition and structure (middle atmosphere · composition and chemistry; instruments and techniques)

Chronic mucus hypersecretion (CMH) is associated with an increased frequency of respiratory infections, excess lung function decline, and increased hospitalisation and mortality rates in the general population. It is associated with smoking, but it is unknown why only a minority of smokers develops CMH. A plausible explanation for this phenomenon is a predisposing genetic constitution. Therefore, we performed a genome wide association (GWA) study of CMH in Caucasian populations.GWA analysis was performed in the NELSON-study using the Illumina 610 array, followed by replication and meta-analysis in 11 additional cohorts. In total 2,704 subjects with, and 7,624 subjects without CMH were included, all current or former heavy smokers (≥20 pack-years). Additional studies were performed to test the functional relevance of the most significant single nucleotide polymorphism (SNP).A strong association with CMH, consistent across all cohorts, was observed with rs6577641 (p = 4.25×10(-6), OR = 1.17), located in intron 9 of the special AT-rich sequence-binding protein 1 locus (SATB1) on chromosome 3. The risk allele (G) was associated with higher mRNA expression of SATB1 (4.3×10(-9)) in lung tissue. Presence of CMH was associated with increased SATB1 mRNA expression in bronchial biopsies from COPD patients. SATB1 expression was induced during differentiation of primary human bronchial epithelial cells in culture.Our findings, that SNP rs6577641 is associated with CMH in multiple cohorts and is a cis-eQTL for SATB1, together with our additional observation that SATB1 expression increases during epithelial differentiation provide suggestive evidence that SATB1 is a gene that affects CMH.

Introduction HDL is an apolipoprotein A-I-containing lipoprotein with atheroprotective functions, and the levels of HDL cholesterol inversely correlate with the risk of coronary artery disease (1), (2). HDL is the [...], HDL has anti-atherogenic properties, and plasma levels of HDL cholesterol correlate inversely with risk of coronary artery disease. HDL reportedly functions as a cofactor to the anticoagulant activated protein C (APC) in the degradation of factor Va (FVa). The aim of the present study was to elucidate the mechanism by which HDL functions as cofactor to APC. Consistent with a previous report, HDL isolated from human plasma by ultracentrifugation was found to stimulate APC-mediated degradation of FVa. However, further purification of HDL by gel filtration revealed that the stimulating activity was not a property of HDL. Instead, the stimulating activity eluted completely separately from HDL in the high-molecular-weight void volume fractions. The active portion of these fractions stimulated FVa degradation by APC and supported the assembly of factor Xa and FVa into a functional prothrombinase complex. Both the procoagulant and anticoagulant activities were blocked by addition of annexin V, suggesting that the active portion was negatively charged phospholipid membranes. These results demonstrate that HDL does not stimulate the APC/protein S effect and that the activity previously reported to be a property of HDL is instead caused by contaminating negatively charged phospholipid membranes.

We presented time series of total ozone column amounts (TOCAs) and erythemal UV (EUV) doses derived from measurements by TOMS (Total Ozone Mapping Spectrometer) instruments on board the Nimbus-7 (N7) and the Earth Probe (EP) satellites for three locations within the equatorial African belt for the period 1979 to 2000. The locations were Dar-es-Salaam (6.8° S, 39.26° E) in Tanzania, Kampala (0.19° N, 32.34° E) in Uganda, and Serrekunda (13.28° N, 16.34° W) in Gambia. Equatorial Africa has high levels of UV radiation, and because ozone shields UV radiation from reaching the Earth's surface, there is a need to monitor TOCAs and EUV doses. In this paper we investigated the trend of TOCAs and EUV doses, the effects of annual and solar cycles on TOCAs, as well as the link between lightning and ozone production in the equatorial African belt. We also compared clear-sky simulated EUV doses with the corresponding EUV doses derived from TOMS measurements. The TOCAs were found to vary in the ranges 243 DU − 289 DU, 231 DU − 286 DU, and 236 DU − 296 DU, with mean values of 266.9 DU, 260.9 DU, and 267.8 DU for Dar-es-Salaam, Kampala and Serrekunda, respectively. Daily TOCA time series indicated that Kampala had the lowest TOCA values, which we attributed to the altitude effect. There were two annual ozone peaks in Dar-es-Salaam and Kampala, and one annual ozone peak in Serrekunda. The yearly TOCA averages showed an oscillation within a five-year period. We also found that the EUV doses were stable at all three locations for the period 1979−2000, and that Kampala and Dar-es-Salaam were mostly cloudy throughout the year, whereas Serrekunda was mostly free from clouds. It was also found that clouds were among the major factors determining the level of EUV reaching the Earth´s surface. Finally, we noted that during rainy seasons, horizontal advection effects augmented by lightning activity may be responsible for enhanced ozone production in the tropics.

A six-channel moderate-bandwidth filter instrument for measurement of UV and visible radiation has been developed. The characteristics of the instrument are described, including the spectral and the angular responses. Furthermore the calibration procedure is outlined. Combining information from several channels, one may determine the total ozone-column amount, various biological dose rates, a cloud transmission factor, and the effective cloud optical depth. The methods used to determine these parameters are presented, and the measured parameters are compared with similar ones obtained from other instruments. The total ozone as measured by the instrument agrees with measurements from a standard Brewer to -0.05% [+ or -] 2.04% over a two-year period. Two weeks of cloudless Commission Internationale de L'Eclairage dose rates agree with those from a Bentham double monochromator spectroradiometer to 0.99 [+ or -] 0.03. OCIS codes: 010.1280, 120.0120, 010.4950.

After the decrease of ozone-depleting substances (ODSs) as a consequence of the Montreal Protocol, it is still challenging to detect a recovery in the total column amount of ozone (total ozone) at northern high-latitudes. To assess regional total ozone changes in the "ozone-recovery"-period (2000-2020) at northern high-latitudes, this study investigates trends from ground-based total ozone measurements at three stations in Norway (Oslo, Andøya, and Ny-Ålesund). For this purpose, we combine measurements from Brewer spectrophotometers, ground-based UV filter radiometers (GUVs), and a SAOZ instrument. The Brewer measurements have been extended to work under cloudy conditions using the global irradiance (GI) technique, which is also presented in this study. We derive trends from the combined ground-based time series with the multiple linear regression model from the Long-term Ozone Trends and Uncertainties in the Stratosphere (LOTUS) project. We evaluate various predictors in the regression model and found that tropopause pressure and lower-stratospheric temperature contribute most to ozone variability at the three stations. We report significant positive trends at Andøya (0.9% per decade) and NyÅlesund (1.5% per decade) and no annual trends at Oslo, but significant positive trends in autumn at all stations. Finally we found positive but insignificant trends of around 3% per decade in March at all three stations, which may be an indication for Arctic spring-time ozone recovery. Our results contribute to a better understanding of regional total ozone trends at northern high-latitudes, which is essential to assess how Arctic ozone responds to changes in ODSs and to climate change. [ABSTRACT FROM AUTHOR]

Research has been conducted on the C4b-binding protein, a complement activation inhibitor. The ability of the protein's alpha-chains to polymerize has been tested and the results are reported.

Author(s): Anne Angelillo-Scherrer [1, 5]; Pablo Garcia de Frutos [2, 5]; Cristina Aparicio [2]; Els Melis [1]; Pierre Savi [3]; Florea Lupu [4]; Jef Arnout [1]; Mieke Dewerchin [1]; Marc [...]

Research has been conducted on the activated protein C. The use of molecular modeling and site-directed mutagenesis in creating a human protein C resistant to alpha1-antitrypsin inhibition is described.

Research was conducted to determine if the coagulation factor V (FV) heterogeneity is caused by partial glycosylation of Asn2181 by modifying the consensus sequence for glycosylation via site-directed mutagenesis and expressing the mutant FV variants in eukaryotic cells. Results demonstrate that replacement of Ser2183 with a Thr increased the efficiency of glycosylation while a Ser2183 to Ala mutation was caused by the loss of glycosylation.

Some problems arising from modeling social variables influencing municipal theft rates in Sweden can be solved through the use of non-linear, longitudinal and comprehensive models. Variables such as the number of populations known for high levels of criminal activity, family disintegration and cultural estrangement may be accommodated in this type of model. Moreover, it allows the analysis of causal processes related to theft rates. However, problems may still arise such as the difficulty in making statistical inferences in a non-linear, longitudinal model.

Bovine and human protein C exhibit high homology in the amino acids of their GLA domains, in spite f the higher membrane affinity of the human protein. The difference may be due to the presence of proline at position 10 of bovine protein C and the presence of histidine at position 10 of human protein C. The effects of replacing proline 10 in bovine protein C with histidine, and the reveres in human protein C have been studied, and the protein containing proline-10 showed lower membrane affinity in both cases.

A method is described for deriving total ozone abundances from zenith-sky intensities measured by an UV-visible spectrometer, known as the System of Analysis of Observations at Zenith (SAOZ). Total ozone abundances are determined by comparison of intensity ratios measured at two wavelengths in the UV region with ratios computed with a radiative transfer model. The wavelength pair 320-307 nm was used in this study. Spectra recorded by the SAOZ spectrometer in Oslo (60 [degrees] N) from the beginning of May 1995 to the end of August 1995 were analyzed, and the results were compared with total ozone measured with a Brewer instrument. The relative difference in derived ozone abundances for the whole period, including days with thin and medium-thick cloud covers, is -0.18 [+ or -] 1.46%. We study the effects of clouds and varying ground albedo on the derived total ozone. Clouds result in an overestimation of the derived total ozone. The error increases with the optical depth of the cloud from approximately 2% for an optically thin cloud ([Tau] = 0.5) to approximately 10% for a thick cloud ([Tau] = 50). The ratio between measured intensities at 550 and 350 nm, the so-called color index, can be used as a measure of the cloud optical depth for thin and medium-thick clouds. The effects of thin and medium-thick clouds on the derived ozone abundances can be compensated for by use of an empirical relationship found between the measured color index and the error in the inferred ozone abundances caused by cloud scattering. We also study the influence of changes in the ground albedo and in the ozone profiles on derived total ozone values. Key words: Ozone, spectroscopy, UV-visible spectrometer, stratosphere.

Vitamin K-dependent proteins of human and bovine forms were compared to identify specific amino acids that may contribute to the divergence in membrane-binding proteins. Amino acid substitutions at positions 11, 33, and 34 were suggested to be responsible for the differences in membrane contact properties. An isolated protein-lipid ion was proposed as a membrane contact mechanism.

The interaction between vitamin K-dependent protein S and the C4b-binding protein has been investigated. The affinity and the association/dissociation rates of the complex have been measured for human and bovine protein S at different calcium concentrations. The results showed that there is thermodynamic coupling between the C4b-binding function and high-affinity Ca2+ binding to protein S.

I describe a method to derive biologically effective UV dose rates, total ozone abundances, and cloud optical depths from irradiance measurements with moderate bandwidth filter instruments that have only a few channels in the UV region. These quantities are determined when the measured irradiances are combined with radiative transfer calculations. The method was applied to a four-channel filter instrument with center wavelengths at 305, 320, 340, and 380 nm and bandwidths of 10 nm. I compared the instrument with a high-wavelength-resolution spectroradiometer during a 1-week period in San Diego, California, with variable cloudiness. The relative difference in Commission Internationale de l'Eclairage (CIE)-weighted UV dose rates for solar zenith angle's (SZA's) [less than] 80 [degrees] was 1.4 [+ or -] 3.2%. The relative difference for clear sky was 0.6 [+ or -] 1.5% for SZA's [less than] 80 [degrees]. The total ozone inferred from the irradiance measurements with the filter instrument is insensitive to clouds. The instrument was compared with a Dobson and a Brewer instrument in Oslo, Norway, 60 [degrees] N, for more than 1 year. The relative difference in derived ozone abundance for the entire period, including cloudy days, was 0.3 [+ or -] 2.9%. The standard deviation was reduced to 1.9% when only clear sky and SZA's [less than] 60 [degrees] were included. By using the total ozone and the cloud optical depth derived from the filter instrument as input to a radiative transfer model, one can compute a complete spectrum from 290 to 400 nm with 1-nm resolution. Such calculated spectra are in good agreement with spectra measured simultaneously with a high-wavelength-resolution spectroradiometer for clear as well as cloudy sky conditions and can be used to determine dose rates for any desired action spectrum. Only one UV-B channel and one UV-A channel are required to compute the spectra. Key words: UV radiation, UV doses, ozone, radiometer, cloud transmission.

Resistance to the anticoagulant activated protein C (APC) appears to be inherited and associated with familial thrombosis. Protein C is important in the prevention of blood clots. Thrombosis is the formation of blood clots. A total of 104 patients with thrombosis were compared with 130 patients without (comparison group). Additionally, 211 family members of 34 patients with thrombosis and resistance to APC were evaluated. APC resistance ratios of less than 2.0, calculated using a modified blood clotting measure, were associated with thrombosis. Approximately 45% of family members of patients had a ratio of less than 2.0. Forty percent of patients with thrombosis had ratios below 2.0. However, 50% of patients with a family history of thrombosis had ratios below 2.0. In the comparison group, only 7% had ratios below 2.0. Those with APC resistance appear at an increased risk of thrombosis.

A mechanism for familial thromboembolic disease that is characterized by a poor anticoagulant response to activated protein C (APC) was described. A new coagulation-based assay was developed to measure anticoagulant response in plasma to added APC. Based on experimental data and observations made in an individual patient with thromboembolic disease, it was hypothesized that the inherited poor anticoagulant response to APC is due to an unknown APC cofactor.

The binding of protein S to platelets was examined using fluorescein 5-isothiocyanate-labeled monoclonal antibodies and fluorescence-gated flow cytometry. It was found that protein S binds specifically to membrane microparticles which formed during platelet activationbut not to the remnant activated platelets. Moreover, protein S supported binding of both protein C and activated protein C to microparticles.

Research was conducted on the interaction of pentraxins with phosphorylcholine and phosphorylethanolamine. Results showed that the serum amyloid P component pentraxin type bound to phosphorylated compounds but had an elevated specificity for phosphorylethanolamiine. Further results also revealed a complementary and related function for the pentraxins. The experimental findings indicated new methods to examine pentraxin functions.