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The study aimed to review and report the current evidence supporting the use of mouthwashes as a preprocedural protocol on dental offices.This study is a secondary one that performed a comprehensive literature search of scientific studies published up to 10th August 2020 in PubMed, Scopus, Web of Science, and Scientific Electronic Library Online (Scielo) databases. The electronic search strategy was performed using free text and DeCS/MeSH terms.Only five studies were included in this work, despite 140 studies that were identified with the research strategy. In vivo studies were carried out in two works, in vitro studies were described in two papers, and a in silico approach was used in one work. No cetylpyridinium chloride studies were identified, while chlorhexidine and povidone studies were more studied.There is reduced evidence about how preprocedural mouthwashes decrease SARS-CoV-2 salivary load.

Mean sea level is a variable of considerable interest in meteorological and oceanographic studies, particularly long-term sea level variation and its relation to climate changes. This study concerns the analysis of monthly mean sea level data from tide gauge stations in the Northeast Atlantic with long and continuous records. Much research effort on mean sea level studies has been focused on identifying long-term linear trends, usually estimated through least-squares fitting of a deterministic function. Here, we estimate nonparametric and robust trends using lowess, a robust smoothing procedure based on locally weighted regression. This approach is more flexible than a linear trend to describe the deterministic part of the variation in tide gauge records, which has a complex structure. A common trend pattern of reduced sea levels around 1975 is found in all the analysed records and interpreted as the result of hydrological and atmospheric forcing associated with drought conditions at the tide gauge sites. This feature is overlooked by a linear regression model. Moreover, nonlinear deterministic behaviour in the time series, such as the one identified, introduces a bias in linear trends determined from short and noisy records.Key words. Oceanography: physical (sea level variations); Hydrology (water balance)

Launched on 16 February 2016, Sentinel-3A (S3A) carries a two-band microwave radiometer (MWR) similar to that of Envisat, and is aimed at the precise retrieval of the wet tropospheric correction (WTC) through collocated measurements using the Synthetic Aperture Radar Altimeter (SRAL) instrument. This study aims at presenting an independent assessment of the WTC derived from the S3A MWR over the open and coastal ocean. Comparisons with other four MWRs show Root Mean Square (RMS) differences (cm) of S3A with respect to these sensors of 1.0 (Global Precipitation Measurement (GPM) Microwave Imager, GMI), 1.2 (Jason-2), 1.3 (Jason-3), and 1.5 (Satellite with ARgos and ALtika (SARAL)). The linear fit with respect to these MWR shows scale factors close to 1 and small offsets, indicating a good agreement between all these sensors. In spite of the short analysis period of 10 months, a stable temporal evolution of the S3A WTC has been observed. In line with the similar two-band instruments aboard previous European Space Agency (ESA) altimetric missions, strong ice and land contamination can be observed, the latter mainly found up to 20–25 km from the coast. Comparisons with the European Centre for Medium-Range Weather Forecasts (ECMWF) and an independent WTC derived only from third party data are also shown, indicating good overall performance. However, improvements in both the retrieval algorithm and screening of invalid MWR observations are desirable to achieve the quality of the equivalent WTC from Jason-3. The outcome of this study is a deeper knowledge of the measurement capabilities and limitations of the type of MWR aboard S3A and of the present WTC retrieval algorithms.

We describe radar measurements of waves, currents and winds made on the coast of northern Scotland during two 2013/14 winter storms, giving methods, results and interpretation. Wave parameters (height, period, direction and short-wave/wind direction) were derived and compared with measurements made by a neighboring buoy and local weather stations. Wind direction and current velocity maps were produced and the interactions of winds and currents discussed. Significant oscillations in wave parameters were observed, which appear to be due to forcing by tidal current velocity variations. The oscillations in waveheight are explained using hydrodynamic analysis and derived amplitudes are compared with radar measurements.

Satellite altimetry has been widely used to study the variability of the ocean currents such as the Azores Current (AzC) in the North Atlantic. Most analyses are performed over the region that encloses the current, thus being somehow affected by other oceanographic signals, e.g., eddies. In this study, a new approach for extracting the axis of a zonal current solely based on satellite altimetry is presented. This is a semi-automatic procedure that searches for the maximum values of the gradient of absolute dynamic topography (ADT), using the geostrophic velocity as auxiliary information. The advantage of this approach is to allow the analyses to be performed over a buffer centered on the current axis instead of using a wider region. It is here applied to the AzC for the period June 1995–October 2006. Regular 0.25° × 0.25° latitude–longitude grids of multi-mission sea level anomaly (SLA) were generated at a 10-day interval for the Northeast Atlantic using an optimal interpolation methodology with a realistic space-time correlation function. From these, regular grids of ADT and horizontal components of surface geostrophic velocity ( U , V ) were generated. By applying the methodology to these oceanographic fields, the AzC axis position for each 10-day frame has been derived. The time-mean position of the AzC axis shows a good agreement with the highest root-mean-square values of sea level anomaly in the Azores Current region. Zonal means of axis position, SLA and U and V have been calculated over the longitude range of the current (35°W–15°W) to assess the AzC variability. The decomposition of the time series of the zonal mean of AzC position into trend and seasonal components shows the existence of significant inter-annual variability in the axis position, while seasonal variability is small. The AzC is found at its southernmost position from the beginning of the period to mid-1998, the minimum value occurring in late summer of 1996, and a northward displacement of the jet position is clearly visible up to the end of 2006.

Sea level is an important parameter in climate and oceanographic applications. In this work the scaling behavior of sea level is analyzed from time series of sea level observations. The wavelet domain is particularly attractive for the identification of scaling behavior in an observed time series. The wavelet spectrum from a scale-by-scale wavelet analysis of variance reproduces in the wavelet domain the power laws underlying a scaling process, allowing the estimation of the scaling exponent from the slope of the wavelet spectrum. Here the scaling exponent is estimated in the wavelet domain for time series of sea level observations in the North Atlantic: at coastal sites from tide gauges, covering 50 years of monthly measurements, and in the open ocean from satellite altimetry, covering 12 years of satellite measurements at 10 days intervals. Both tide gauge and altimetry time series exhibit scaling behavior. Furthermore, the degree of stochastic persistence is spatially coherent and distinct at the coast and in the open ocean. Near the coast, the stochastic structure of the sea level observations is characterized by long-range dependence with a moderate degree of persistence. Larger values of the scaling exponent, consistent with weaker persistence, are concentrated in the northern Atlantic. At mid-latitudes the stochastic dependence of sea level observations is characterized by strong persistence in the form of strong long-range and 1/f dependence.

The North Atlantic Oscillation (NAO) is one of the most important climatic patterns in the Northern Hemisphere. Indices based on the normalised pressure difference between Iceland and a southern station, such as Lisbon or Gibraltar, have been defined in order to describe NAO temporal evolution. Although exhibiting interannual and decadal variability, the signals are statistically rather featureless and therefore it is difficult to discriminate between different types of stochastic models. In this study, Lisbon and Gibraltar NAO winter indices are analysed using the discrete wavelet transform discrete wavelet transform(DWT). A multi-resolution analysis (MRA) is carried out for a scale-based description of the indices and the wavelet spectrum is used to identify and estimate long-range dependence. The degree of association of the two NAO indices is assessed by estimating the wavelet covariance for the two signals. The scale-based approach inherent to the discrete wavelet methodology allows a scale-by-scale comparison of the signals and shows that although the short-term temporal pattern is very similar for both indices, the long-term temporal structure is distinct. Furthermore, the degree of persistence or ‘memory’ is also distinct: the Lisbon index is best described by a long-range dependent (LRD) process, while the Gibraltar index is adequately described by a short-range process. Therefore, while trend features in the Lisbon NAO index may be explainable by long-range dependence alone, with no need to invoke external factors, for the Gibraltar index such features cannot be interpreted as resulting only from internal variability through long-range dependence. Copyright  2006 Royal Meteorological Society.

Sea level is one of the 50 Essential Climate Variables (ECVs) listed by the Global Climate Observing System (GCOS) in climate change monitoring. In the last two decades, sea level has been routinely measured from space using satellite altimetry techniques. In order to address a number of important scientific questions such as: "Is sea level rise accelerating?", "Can we close the sea level budget?", "What are the causes of the regional and interannual variability?", "Can we already detect the anthropogenic forcing signature and separate it from the internal/natural climate variability?", and "What are the coastal impacts of sea level rise?", the accuracy of altimetry-based sea level records at global and regional scales needs to be significantly improved. For example, the global mean and regional sea level trend uncertainty should become better than 0.3 and 0.5 mm year−1, respectively (currently of 0.6 and 1–2 mm year−1). Similarly, interannual global mean sea level variations (currently uncertain to 2–3 mm) need to be monitored with better accuracy. In this paper, we present various respective data improvements achieved within the European Space Agency (ESA) Climate Change Initiative (ESA CCI) project on "Sea Level" during its first phase (2010–2013), using multi-mission satellite altimetry data over the 1993–2010 time span. In a first step, using a new processing system with dedicated algorithms and adapted data processing strategies, an improved set of sea level products has been produced. The main improvements include: reduction of orbit errors and wet/dry atmospheric correction errors, reduction of instrumental drifts and bias, inter-calibration biases, intercalibration between missions and combination of the different sea level data sets, and an improvement of the reference mean sea surface. We also present preliminary independent validations of the SL_cci products, based on tide gauges comparison and sea level budget closure approach, as well as comparisons with ocean re-analyses and climate model outputs.

Over 72 mutations have been identified in the HEXA gene of which only four (T538C, A590C, G805A, and C1495T) are believed to cause a chronic form of Tay-Sachs disease (TSD). We identified a novel HEXA mutation (IVS7, -7 G--A) leading to chronic TSD in a Canadian patient of English ancestry. The second allele in this patient was the exon 11 4-bp insertion mutation (/1277TATC), which is the most frequent TSD allele in Ashkenazi Jews. The IVS7, -7 G--A mutation introduces a new 3' splice acceptor site 5 bp upstream of the normal intron 7 splice acceptor site. The mutation leads to reduction of steady-state levels of HEXA mRNA by more than 80%. Two mRNA species are produced by the IVS7, -7 G--A allele; a normal nRNA species and an mRNA lacking exon 8. No mRNA species that was spliced at the upstream 3' splice acceptor site was detected. We used competitive PCR to quantitate mRNA species in fibroblasts obtained from this patient. We compared the amounts of three identified mRNA species to HEXA mRNA levels in cells from normal individuals and from individuals heterozygous for /1277TATC. The steady-state level of HEXA mRNA in cells from a normal individual was 17.3 pg/microg RNA. An individual heterozygous for /1277TATC produced 8.7 pg of normal HEXA mRNA/microg RNA. The HEXA mRNA species with the insertion mutation was present in patient cells at 4.8% of the level of normal HEXA nRNA in homozygous normal cells. In fibroblasts from the patient carrying the IVS7, -7 G--A mutation, the steady-state level of exon 8-deleted HEXA mRNA was 5.9% the level of that produced by homozygous normal cells. The level of normal HEXA nRNA in this patient's cells was 10.4%.

Due to its large space-time variability, the wet tropospheric correction (WTC) is still considered a significant error source in satellite altimetry. This paper presents the GNSS (Global Navigation Satellite Systems) derived Path Delay Plus (GPD+), the most recent algorithm developed at the University of Porto to retrieve improved WTC for radar altimeter missions. The GPD+ are WTC estimated by space-time objective analysis, by combining all available observations in the vicinity of the point: valid measurements from the on-board microwave radiometer (MWR), from GNSS coastal and island stations and from scanning imaging MWR on board various remote sensing missions. The GPD+ corrections are available both for missions which do not possess an on-board microwave radiometer such as CryoSat-2 (CS-2) and for all missions which carry this sensor, by addressing the various error sources inherent to the MWR-derived WTC. To ensure long-term stability of the corrections, the large set of radiometers used in this study have been calibrated with respect to the Special Sensor Microwave Imager (SSM/I) and the SSM/I Sounder (SSM/IS). The application of the algorithm to CS-2 and Geosat Follow-on (GFO), as representative altimetric missions without and with a MWR aboard the respective spacecraft, is described. Results show that, for both missions, the new WTC significantly reduces the sea level anomaly (SLA) variance with respect to the model-based corrections. For GFO, the new WTC also leads to a large reduction in SLA variance with respect to the MWR-derived WTC, recovering a large number of observations in the coastal and polar regions and full sets of tracks and several cycles when MWR measurements are missing or invalid. Overall, the algorithm allows the recovery of a significant number of measurements, ensuring the continuity and consistency of the correction in the open-ocean/coastal transition zone and at high latitudes.

The altimeter range should be corrected for tropospheric path delays due to atmospheric pressure at sea level and atmospheric humidity. Over open ocean, these corrections are performed with enough accuracy using the microwave radiometer for the wet path delay and meteorological model analyses for the dry path delay. In coastal areas, specific studies are needed to assess the quality of the standard products and to propose specific processing if necessary. For the wet tropospheric correction, new promising approaches are presented based on optimal combination of radiometer, meteorological model, GNSS and land information. For the dry tropospheric correction, an assessment of the accuracy of the model-based estimation is provided.

A comparative study is carried out for sea level observations in the North Atlantic from tide gauges and satellite altimetry. Monthly tide gauge records from 12 stations in both sides of the North Atlantic from January 1993 to December 2003 and monthly time series of sea level anomalies derived from TOPEX measurements are considered. The degree of association between tide gauge and altimetry observations is analysed for different scales by computing the correlation between the sea level components resulting from a multiresolution analysis based on the maximal overlap discrete wavelet transform. A similar correlation analysis is carried out to assess the relationship between the sea level observations and climate variables: sea surface temperature, precipitation rate and wind speed. The results show that altimetry and tide gauge observations are strongly correlated, as expected, but also that the relation is scale dependent, with covariability driven by the seasonal signal for most stations. For all variables the obtained correlation patterns exhibit significant spatial variability reflecting the diversity of local conditions affecting coastal sea level.

The characterisation and quantification of long-term sea-level variability is of considerable interest in a climate change context. Long time series from coastal tide gauges are particularly appropriate for this purpose. Long-term variability in tide gauge records is usually expressed through the linear slope resulting from the fit of a linear model to the time series, thus assuming that the generating process is deterministic with a short memory component. However, this assumption needs to be tested, since trend features can also be due to non-deterministic processes such as random walk or long range dependent processes, or even be driven by a combination of deterministic and stochastic processes. Specific methodology is therefore required to distinguish between a deterministic trend and stochastically-driven trend-like features in a time series. In this chapter, long-term sea-level variability is characterised through the application of (i) parametric statistical tests for stationarity, (ii) wavelet analysis for assessing scaling features, and (iii) generalised least squares for estimating deterministic trends. The results presented here for long tide gauge records in the North Atlantic show, despite some local coherency, profound differences in terms of the low frequency structure of these sea-level time series. These differences suggest that the long-term variations are reflecting mainly local/regional phenomena.

A novel type II integral membrane protein has been identified in the course of screening for genes overexpressed in a mouse model of chronic myelogenous leukemia blast crisis. This new protein, designated NKCL, consists of a 210-amino acid polypeptide with a short, NH2-terminal cytoplasmic tail of 17 amino acids preceding a transmembrane domain and a COOH-terminal extracellular region. The COOH-terminal 132 amino acids bear typical features of the C-type animal lectin carbohydrate-recognition domain. The Nkcl gene is unique in that it maps just proximal to the region of the genome that encodes group V members of the C-type animal lectin family near the natural killer gene complex on mouse chromosome 6, but its protein product also has features of several group II C-type animal lectins. Most notably, it has a complete Ca2+-binding site 2, which forms part of the sugar-binding site in other members of the family, and binds mannose in a Ca2+-dependent manner. Moreover, its expression is not restricted to natural killer cells, as reported for the majority of group V lectins. Nkcl is expressed in pluripotent myeloid precursors, precursor and mature macrophages, and neutrophils.

The cytotoxicity of isophenphos, an organophosphorus insecticide that has the potential to cause delayed polyneuropathy, was evaluated in GBK and V79 cells. A 72 h time course following isophenphos exposure indicated a dose-dependent growth inhibition as determined by cell counts. The administration of isophenphos (20 g/ml) to GBK cells cultured at high densities indicated a decrease in the activities of LDH isoenzymes. Analysis of V79 cells revealed a decrease of LDH3, the only LDH isoenzyme detected in these cells.

1. Serum serotonin (5HT) was determined in normal and autistic children by high performance liquid chromatography with electrochemical detection (HPLC-ED), after serum deproteinization. 2. The sample deproteinization was carried out by the addition of 3.4 M HCLO4 to a small volume of the serum, followed by freezing, centrifugation, dilution and injection of sample into the HPLC. 3. Serum 5HT concentration was significantly increased in autistic children (303 +/- 92 ng/ml) (N = 19) when compared to that of normal children (215 +/- 67 ng/ml) (N = 46). The data of normal children analyzed by ANOVA for sex or age showed no difference. 4. The method employed in this study showed high resolution, good sensitivity and can be used for routine determination of serum 5HT in the clinical investigation of hyperserotonemia in autism.

This study aimed to characterise the nutritional intake according the use of nutritional supplements (NS) by elite adult Portuguese athletes. Two hundred and two adult (23±4 years) athletes (78% males), representatives of Portugal in 13 sports, voluntarily filled a semiquantitative food-frequency questionnaire and a questionnaire about the use of NS. The total nutritional daily intake did not consider the nutrients provided by NS. Statistical analyses were performed using SPSS V.16.0. The majority of athletes (74%) reported having used at least one NS in the previous year, with a mean consumption of 5.9±3.7 NS per athlete. The most frequently consumed nutritional supplements were sport drinks (63%), proteins (58%), magnesium (56%), iron (30%), vitamin C (29%), sport gels (23%), antioxidants (21%), vitamin B12 (15%) and vitamin E (9%). The mean energy intake was 2875±1313 kcal/days, for males, and 2612±1152 kcal/days, for females. For proteins, the males9 intake was 1.7±0.8 g/kg/days and females9 intake was 2.1±1.2 g/kg/days. Males consumed 4.8±2.5 g/kg/days of carbohydrates, while females consumed 5.6±2.6 g/kg/days. Intake of less than recommended was observed in 33% for vitamin E in females, and 17% for vitamin E, 5% for folate and 5% for magnesium, in male athletes. For all other micronutrients intakes were above recommended amounts for both genders. There were no differences in the vitamin and mineral intake between supplement users and nonusers, for both genders. The use of NS is very prevalent in elite adult Portuguese athletes and not associated with nutritional total intake.

Tay-Sachs disease (TSD), a neurodegenerative disorder resulting from a deficiency of the lysosomal enzyme hexosaminidase A (HexA), clusters in Ashkenazic Jews. Population-based screening programs to detect carriers of TSD genes by means of HexA assays have been active since the 1970s. The recent characterization of 3 mutations in the HEXA gene (in exon 7, exon 11, and intron 12), which account for over 90% of HEXA mutations in Ashkenazim, appeared to offer better options for screening and diagnosis. The relative frequencies of the three mutations in Montreal are similar to those reported in four other North American populations. We compared enzyme and DNA analyses to determine specificity and sensitivity of each test when the other was used as the confirmatory procedure. Neither procedure has a sensitivity of 1.0. Maximum sensitivity and specificity were achieved by using both tests together. The findings here are likely to apply to most cases where the variant screened enzyme phenotype can result from more than one mutation.

Sea level is a key variable in the context of global climate change. Climate-induced variability is expected to affect not only the mean sea level but also the amplitude and phase of its seasonal cycle. This study addresses the changes in the amplitude and phase of the annual cycle of coastal sea level in the extra-tropical North Atlantic. The physical causes of these variations are explored by analysing the association between fluctuations in the annual amplitude of sea level and in ancillary parameters [atmospheric pressure, sea-surface temperature and North Atlantic Oscillation (NAO) winter index]. The annual cycle is extracted through autoregressive decomposition, in order to be able to separate variations in seasonality from long-term interannual variations in the mean. The changes detected in the annual sea level cycle are regionally coherent, and related to changes in the analysed forcing parameters. At the northern sites, fluctuations in the annual amplitude of sea level are associated with concurrent changes in temperature, while atmospheric pressure is the dominant influence for most of the sites on the western boundary. The state of the NAO influences the annual variability in the Southern Bight, possibly through NAO-related changes in wind stress and ocean circulation.

This work addresses the autoregressive modelling of sea level time series from TOPEX/Poseidon satellite altimetry mission. Datasets from remote sensing applications are typically very large and correlated both in time and space. Multivariate analysis methods are useful tools to summarise and extract information from such large space-time datasets. Multivariate autoregressive analysis is a generalisation of Principal Oscillation Pattern (POP) analysis, widely used in the geosciences for the extraction of dynamical modes by eigen-decomposition of a first order autoregressive model fitted to the multivariate dataset of observations. The extension of the POP methodology to autoregressions of higher order, although increasing the difficulties in estimation, allows one to model a larger class of complex systems. Here, sea level variability in the North Atlantic is modelled by a third order multivariate autoregressive model estimated by stepwise least squares. Eigen-decomposition of the fitted model yields physically-interpretable seasonal modes. The leading autoregressive mode is an annual oscillation and exhibits a very homogeneous spatial structure in terms of amplitude reflecting the large scale coherent behaviour of the annual pattern in the Northern hemisphere. The phase structure reflects the seesaw pattern between the western and eastern regions in the tropical North Atlantic associated with the trade winds regime. The second mode is close to a semi-annual oscillation. Multivariate autoregressive models provide a useful framework for the description of time-varying fields while enclosing a predictive potential.

This study is concerned with the determination of a high resolution regional geoid in the area surrounding the Azores Islands, integrating multi-sensor airborne and marine observations with satellite derived and land gravity. It aims to prove the usefulness of airborne data in complementing existing marine and satellite derived gravity in coastal and insular regions, bridging the gap between land areas and the open ocean.

Spatial and temporal sea level variability in the North Atlantic is investigated from Topex/Poseidon (T/P) altimetry data. Time series of sea level anomalies on a regular 5° grid are analysed. Non-linear denoising through thresholding in the wavelet transform domain is carried out for each series in order to remove noise while preserving non-smooth features. Principal Component Analysis (PCA) is used to obtain a spatio-temporal description of the sea level field. To avoid modal mixing and improve interpretation of the principal modes, PCA is implemented separately for seasonal and trend components of the sea level field obtained from a wavelet-based multiresolution analysis. The leading pattern of the seasonal field reflects the dominance of a stable annual cycle over the study area and the change in the seasonal regime approaching the equator with contribution of the semi-annual cycle and phaseshift in the annual cycle in the tropical Atlantic. The leading pattern of the trend field is a broad spatial pattern associated with North Atlantic Oscillation (NAO), reflecting the influence of atmospheric conditions on interannual sea level variability.

This study concerns the determination of a regional geoid model in the North Atlantic area surrounding the Azores islands by combining multi-mission altimetry from the ERS (European Remote Sensing) satellites and surface gravity data. A high resolution mean sea surface, named AZOMSS99, has been derived using altimeter data from ERS-1 and ERS-2 35-day cycles, spanning a period of about four years, and from ERS-1 geodetic mission. Special attention has been paid to data processing of points around the islands due to land contamination on some of the geophysical corrections. A gravimetric geoid has been computed from all available surface gravity, including land and sea observations acquired during an observation campaign that took place in the Azores in October 1997 in the scope of a European and a Portuguese project. Free air gravity anomalies were derived by altimetric inversion of the mean sea surface heights. These were used to fill the large gaps in the surface gravity and combined solutions were compu...

The gravity field may be determined using different techniques, but airborne gravity surveying is becoming a powerful tool mainly due to its potential in remote areas.

This study addresses the impact of satellite altimetry data processing on sea levelstudies at regional scale, with emphasis on the influence of various geophysical correctionsand satellite orbit on the structure of the derived interannual signal and sea level trend. Thework focuses on the analysis of TOPEX data for a period of over twelve years, for threeregions in the North Atlantic: Tropical (0o≤Æ≤25o), Sub-Tropical (25o≤Æ≤50o) and Sub-Arctic (50o≤Æ≤65o). For this analysis corrected sea level anomalies with respect to a meansea surface model have been derived from the GDR-Ms provided by AVISO by applyingvarious state-of-the-art models for the geophysical corrections. Results show that sea leveltrend determined from TOPEX altimetry is dependent on the adopted models for the majorgeophysical corrections. The main effects come from the sea state bias (SSB), and from theapplication or not of the inverse barometer (IB) correction. After an appropriate modellingof the TOPEX A/B bias, the two analysed SSB models induce small variations in sea leveltrend, from 0.0 to 0.2 mm/yr, with a small latitude dependence. The difference in sea leveltrend determined by a non IB-corrected series and an IB-corrected one has a strong regionaldependence with large differences in the shape of the interannual signals and in the derivedlinear trends. The use of two different drift models for the TOPEX Microwave Radiometer(TMR) has a small but non negligible effect on the North Atlantic sea level trend of about0.1 mm/yr. The interannual signals of sea level time series derived with the NASA and theCNES orbits respectively, show a small departure in the middle of the series, which has noimpact on the derived sea level trend. These results strike the need for a continuousimprovement in the modelling of the various effects that influence the altimetermeasurement.