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This study contributes to the communal effort to improve understanding of sea spray generation and transport. For the first time, laboratory-derived sea spray generation functions (SSGFs) are parameterized in the Meso-NH mesoscale atmospheric model and are field tested. Formulated from the MATE19 laboratory experiments (Bruch et al., 2021) two SSGFs are driven by the upwind component of the wave-slope variance S2x (herein B21A), or both S2x and the wind friction velocity cubed u3* (herein B21B). As part of our first attempt to incorporate the SSGFs in Meso-NH, the simulations are run without a wave model, and the wave-wind SSGFs are assumed wind-dependent. Model evaluation is achieved with sea spray and meteorological measurements acquired over the 0.1-22.75 µm radius range and 1-20 m s-1 U10 wind speeds, 15 meters above the sea surface onboard R/V Atalante during the 25 day SUMOS field campaign in the Bay of Biscay. The B21B SSGF offers particularly good sensitivity to a wide range of environmental conditions over the size range, with an average overestimation by a factor 1.5 compared with measurements, well below the deviations reported elsewhere. B21A also performs well for larger droplets at wind speeds above 15 m s-1. Associated with airflow separation and wave breaking, the wave-slope variance proves to be a key parameter for the scaling of sea spray generation. Using model outputs obtained with B21B, sea spray can be found far beyond the marine atmospheric boundary layer, with large plumes reaching 100 km inland and altitudes of 2.5 km. Plain Language Summary The effects of sea spray on weather and climate remain poorly understood as a result of sparse measurements and large uncertainties in the generation flux. With the aim of improving sea spray transport in atmospheric models, two sea spray generation functions derived from the MATE19 laboratory campaign are parameterized in the Meso-NH mesoscale atmospheric model. The simulations are run over the Bay of Biscay in February-March 2021, and are compared with sea spray concentrations measured during the SUMOS field campaign. Results show that the laboratory-derived generation functions allow accurate predictions of sea spray concentrations. Furthermore, simulations show that sea spray droplets can be transported far over land, and high into the atmosphere.

The atmospheric aerosol has a large influence on global climate through its ability of scattering and absorbing electromagnetic radiation, which affect the Earth's radiative balance. Characteristics, such as size distribution, chemical composition and hygroscopic properties are important for improving global climate model projections of natural sea spray aerosols, which are numerically dominant in the global aerosol budget. Previous experimental studies in coastal locations revealed a complex mixing between natural and anthropogenic aerosols. This complexity makes it difficult to characterize the behavior of natural sea spray aerosols in a simplified form that is suitable for global models. The aim of the present paper is to characterize the size distributions of natural sea spray aerosols at a coastal site in False Bay, South Africa. The opening of False Bay towards the Southern Ocean with unlimited fetch from Antarctica provides a unique opportunity to measure and focus on pristine marine air masses solely. A large observational data set from the First European-South African Transmission Experiment (FESTER) was analyzed and two case studies are presented to illustrate the contribution of sea spray to aerosol size distributions under pure marine and mixed air mass conditions, respectively. A set of conditions for measuring pure marine aerosols in False Bay was established. The results of the relationship of aerosol concentrations with wind speed reveals the distinct behavior of natural sea spray aerosols and demonstrates the pure marine influence of the Southern Ocean in False Bay. Comparison of the aerosol size distributions to a coastal site in the Mediterranean Sea, attest to the contribution of sea spray to aerosol size distributions in False Bay.

This paper discusses the use of smoke obscurants as countermeasures against high energy lasers (HEL). Potential success of the smoke does not depend only the performance of the smoke. The transmission loss in the smoke is part of a chain of system components, including warning sensors, smoke launchers, etc.. The core of the paper deals with experimental work on the following research questions: - Does smoke attenuate an incoming beam of a HEL? - Does the HEL affect the smoke itself? The experimental set-up with the TNO 30kW HEL and the scale model for the smoke transmission path will be shown. Selected experimental results will be shown and discussed. Finally we will compare the results to theoretical calculations and we will analyze the properties of an ideal HEL attenuation smoke.

We report the analysis of radio soundings launched at our permanent measurement site in North-western Germany. The data of potential temperature and wind speed are used to derive vertical profiles of the gradient Richardson number 𝑅𝑖𝑔 in the free troposphere, and subsequently, the strength of optical turbulence 𝐶𝑛 2. These values are compared to a numerical framework, which derives 𝐶𝑛 2 from mesoscale weather prediction data by two schemes based on the gradient Richardson number and Monin-Obukhov similarity theory, respectively.

BackgroundMultiple sclerosis (MS) poses a major threat to sustainable employability. Identifying conditions and factors that promote work participation is of great importance. Our objective was to explore the contribution of personality traits in explaining occupational functioning in MS.Methods241 participants with relapsing-remitting MS (78% female, median age: 42.0 years, median EDSS: 2.0) and 60 healthy controls (70% female, median age: 45.0 years) underwent neuropsychological and neurological examinations and completed questionnaires. Multivariate logistic and linear regression analyses were conducted to examine relations between personality traits and self-reported occupational functioning, while accounting for known correlates.ResultsPersonality traits were not associated with self-reported occupational functioning when correcting for known correlates. A higher impact of fatigue (B = -0.05, p = .005 and B = -0.04, p = .009) and depression (B = -0.22, p = .008 and B = -0.21, p = .01) were associated with no paid job (R2 = 0.13) and considering to reduce work hours (R2 = 0.12). A higher impact of fatigue (B = -0.05, p = .008, β = 0.46, p = .001 and β = −0.36, p = .001) was associated with absenteeism from work (R2 = 0.15), more presenteeism (R2 = 0.35) and lower work ability (R2 = 0.25). A higher impact of fatigue (β = 0.46, p = .001) and anxiety (β = 0.25, p = .001) were associated with more work difficulties (R2 = 0.54).ConclusionPersonality traits did not explain additional variance in self-reported occupational functioning in persons with relapsing-remitting MS with mild disability. The impact of fatigue was the main and most consistent correlate of occupational functioning, often combined with depression or anxiety. Total explained variance of the models was limited, emphasizing the need to additionally examine other (contextual) factors when considering occupational challenges in MS.

We investigate the effects of wind–wave interactions on the surface sea-spray-generation flux. To this end, the Marine Aerosol Tunnel Experiment (MATE2019) was conducted at the Pytheas Institute large wave–wind facility in Luminy (Marseille, France) over the period June–July 2019. A unique range of air–sea boundary conditions was generated by configuring the laboratory with four types of wave forcing and five wind speeds spanning 8–20 m s $$^{-1}$$ . Young and developed waves were included, with wave ages between 1.3 and 9.5 (defined in terms of phase speed and friction velocity). Vertical sea-spray-concentration profiles measured over the 0.1–47.5 $$\upmu $$ m radius range and a flux–profile method allowed estimation of the sea-spray-generation flux. Results show that the flux increases for increased wind-induced wave breaking, and is highest for steep and heavily-breaking waves. Scaling analysis shows that the sea-spray generation is best correlated with the wave-slope variance for larger droplets (20 $$\upmu $$ m and above, assumed predominantly spume droplets generated by surface tearing). For smaller droplets (7–20 $$\upmu $$ m, presumed predominantly jet droplets generated by bubble bursting), the highest correlation is found with a non-dimensional number combining the wave-slope variance with the friction velocity cubed. This is reflected in the formulation of two wave-state-dependent sea-spray-generation functions, each valid for wind speeds 12–20 m s $$^{-1}$$ and droplet radii 3–35 $$\upmu $$ m, thereby covering jet and spume droplet production.

Recent studies stress the importance of considering sea surface wave characteristics in sea spray generation functions (SSGFs). To this end, the effect of interacting winds and waves on sea spray generation was studied using data collected during the Marine Aerosol Tunnel Experiments (MATE2019) conducted at the OSU-Pytheas large wind-wave tunnel facility at Luminy, Marseille (France) (Study detailed in Bruch et al., in review). A total of 20 wind and wave combinations were tested, with wind speeds between 8 and 20 m s-1 combined with pure wind waves and waves generated by a wavemaker, allowing for a range of wave characteristics and wave ages. Similar wind speed profiles and whitecapping behavior between the laboratory and the field suggest that the laboratory is appropriate for the study of sea spray production. The sea spray generation flux was estimated from logarithmic vertical sea spray concentration profiles using a flux-profile method using Monin and Obukhov (1954) theory. Results show that the production of larger droplets at 20-35 µm radius is well correlated with the wave slope variance 2>, whilst the wind friction velocity cubed u*3 performs best over 7-20 µm. Two SSGFs are proposed. The original work presented here is an assessment of the validity of the two SSGFs in the field. The two laboratory-derived SSGFs are tested in two numerical models; the stationary Marine Aerosol Concentration Model (MACMod) (used in Laussac et al., 2018), and the non-hydrostatic mesocale atmospheric model Meso-NH (jointly developed by the LA - UMR 5560 - and the CNRM - UMR 3589). The 2> necessary required by both SSGFs is estimated using a wind-dependent formulation (Cox and Munk, 1956) and a spectral spectral model (Elfouhaily et al., 1997). Results show that the numerical simulations offer good results relative to sea spray measurements obtained in the North-West Mediterranean in fetch-limited conditions (Laussac et al., 2018), as well as other existing SSGFs in the literature. These results suggest that wind-wave tunnel facilities present an interesting alternative for determining the sea spray generation flux, especially in high wind speed conditions in which deployment in the field is difficult.References :Bruch, W., Piazzola, J., Branger, H., van Eijk, A. M. J., Luneau, C., Bourras, D., Tedeschi, G. (In review). Sea Spray Generation Dependence on Wind and Wave Combinations : A Laboratory Study. Submitted in : Boundary Layer Meteorology.Cox, C., & Munk, W. (1956). Slopes of the sea surface deduced from photographs of sun glitter. University of California Press. Vol. 6,9,401-488.Elfouhaily, T., Chapron, B., Katsaros, K., & Vandemark, D. (1997). A unified directional spectrum for long and short wind driven waves. Journal of Geophysical Research: Oceans, 102(C7),15781-15796.Monin, A. S., & Obukhov, A. M. (1954). Basic laws of turbulent mixing in the surface layer of the atmosphere. Contrib. Geophys. Inst. Acad. Sci. USSR,151(163),e187.Laussac, S., Piazzola, J., Tedeschi, G., Yohia, C., Canepa, E., Rizza, U., & Van Eijk, A. M. J. (2018). Development of a fetch dependent sea-spray source function using aerosol concentration measurements in the North-Western Mediterranean. Atmospheric Environment,193,177-189.

Background: Infection with hepatitis E virus genotype 3 (HEV3) is an emerging zoonosis in the industrialized world. The infection usually proceeds asymptomatically. Extrahepatic sequelae including neurological symptoms have been described.Case description: A 52-year-old man presented at the emergency department with pain, muscle weakness and sensory disorders in both shoulders and arms. He was found to have bilateral neuralgic amyotrophy accompanying an HEV3 infection.Conclusion: An HEV3 infection can have neurological sequelae, but very little is known about its incidence and spectrum of symptoms.

Military operations in arid regions of the world are becoming more and more regular. The atmospheric conditions in these regions impose severe restrictions on the performance of optical systems. In contrast to regions, where many airports are located and therefore the monitoring network of ground stations is very dense, only few ground measurements are available for arid regions. To a certain extent, measurements can be collected and generalized with large-scale measurement campaigns, but they are very cost-intensive and partly not achievable due to the political situation. Another possibility to close this gap of data is provided by satellite measurements. For various measurement parameters such as humidity, wind, solar radiation and aerosols, this works quite well with some limitations. For this reason, models are a good complement to fill the lack of data in these regions. The study is concerned with identifying the turbulence in Western Sahara. The models used WRF (Weather Research and Forecasting Model) and ICON (Icosahedral Nonhydrostatic Model) have been sufficiently tested in different regions of the world. As there are no turbulence measurements in the Sahara, this is the first test to estimate the magnitude of the turbulence in order to discuss the need for an extensive measurement campaign. The models can be validated with previous trials of IOSB such as White Sands Missile Range (WSMR) in the USA, (New Mexico).

Our aim is to characterize the optical turbulence over the urban areas. Since it is difficult to measure 𝐶2/𝑛 (see PDF) continuously over an urban area, we explore the possibility of using a mesoscale weather prediction model to predict 𝐶2/𝑛 (see PDF) over the urban area. To this end, the output of the Weather Research and Forecast model (WRF) was coupled with a micrometeorological parametrization, which allowed calculation of 𝐶2/𝑛 (see PDF) at each numerical grid point in the surface layer. Numerical results are compared to data of path-averaged measurements of optical turbulence performed with a large aperture scintillometer (BLS900) over the city of Ettlingen (southwestern Germany) during two time periods in Spring and Summer 2013. Effects of the heat island effect are revealed by high turbulence values, observed at night-time.

We complete the analysis of the data obtained during the experimental campaign around the semi circular bay of Quiberon, France, during two weeks in June 2006 (see Part 1). A reanalysis of numerical simulations performed with the Advanced Regional Prediction System model is presented. Three nested computational domains with increasing horizontal resolution down to 100 m, and a vertical resolution of 10 m at the lowest level, are used to reproduce the local-scale variations of the breeze close to the water surface of the bay. The Weather Research and Forecasting mesoscale model is used to assimilate the meteorological data. Comparisons of the simulations with the experimental data obtained at three sites reveal a good agreement of the flow over the bay and around the Quiberon peninsula during the daytime periods of sea-breeze development and weakening. In conditions of offshore synoptic flow, the simulations demonstrate that the semi-circular shape of the bay induces a corresponding circular shape in the offshore zones of stagnant flow preceding the sea-breeze onset, which move further offshore thereafter. The higher-resolution simulations are successful in reproducing the small-scale impacts of the peninsula and local coasts (breeze deviations, wakes, flow divergences), and in demonstrating the complexity of the breeze fields close to the surface over the bay. Our reanalysis also provides guidance for numerical simulation strategies for analyzing the structure and evolution of the near-surface breeze over a semi-circular bay, and for forecasting important flow details for use in upcoming sailing competitions.

BackgroundRecent studies report deficits in social cognition in individuals with multiple sclerosis (MS). Social cognitive skills such as empathy are important for adequate social and occupational functioning. Our objectives are: (1) to examine whether empathy differs between individuals with MS and healthy controls, (2) to examine relations between empathy and cognitive, psychological and occupational functioning.Methods278 individuals with MS (relapsing-remitting subtype) and 128 healthy controls from the MS@Work study participated in this investigation. The participants completed questionnaires about demographics, cognitive, psychological and occupational functioning, and underwent neurological and neuropsychological examinations. Mann-Whitney U-tests were used to examine group differences in empathy. Pearson and Spearman rank correlation analyses were used to examine relations between empathy and the other measures.ResultsEmpathy did not differ between individuals with MS and healthy controls. In individuals with MS, higher empathy was correlated with a higher educational level (X2(df) = 13.2(2), p = 0.001), better verbal learning (r = 0.20, p = 0.001), less symptoms of depression (r=−0.21, p = 0.001), higher extraversion (r = 0.25, p ≤ 0.001), agreeableness (r = 0.55, p ≤ 0.001) and conscientiousness (r = 0.27, p ≤ 0.001) and better occupational functioning in terms of work scheduling and output demands (r = 0.23, p = 0.002) and less cognitive/psychological work barriers (r = −0.21, p = 0.001). In healthy controls, higher empathy was correlated with less symptoms of depression (r = −0.34, p ≤ 0.001), less fatigue (r = −0.37, p ≤ 0.001), higher agreeableness (r = 0.59, p ≤ 0.001) and better occupational functioning in terms of work ability as compared to lifetime best (r = 0.28, p = 0.001) and less cognitive/psychological work barriers (r = −0.34, p ≤ 0.001). Empathy did not differ between unemployed and employed individuals with MS or healthy controls.ConclusionEmpathy did not differ between individuals with MS and healthy controls. Within both investigated groups, higher empathy was weakly to moderately correlated with less symptoms of depression, higher agreeableness and better occupational functioning. We also found unique correlations for empathy within the investigated groups. Longitudinal studies are needed to further examine social cognition in relation to cognitive, psychological and occupational functioning in both individuals with MS and healthy controls. It would be particularly interesting to concurrently examine changes in the brain network involved with social cognition.

International audience; The coastal aerosol represents a complex mixing between sea spray aerosols locally generated at the sea surface and a component generated by natural and/or anthropogenic sources on the nearby land. The aim of this paper is to study the atmospheric concentrations of carbonaceous compounds as measured in the coastal zone of the Northern Adriatic Sea between April 2017 and April 2018. The results show a quite large contribution of carbonaceous compounds, even when the sampled air mass is predominantly maritime. Although it is generally assumed that 70% and 90% of bulk organic carbon (OC) and elemental carbon (EC) concentrations, respectively, are found in the fine mode, we observed higher OC and EC concentrations in the coarse fraction (up to about 37% and 25%, respectively). This confirms the occurrence of mixing between anthropogenic matter and sea spray, mainly composed of coarse aerosol particles, during the atmospheric transport over the Mediterranean basin.

Military operations on target practice and wind farms demand on knowledge of the turbulent state and wind speed in the surrounding atmosphere. However, the definition of turbulence is completely different in both cases. In the military context we speak about optical turbulence in the wind industry, kinetic turbulence is essential. In the following we want to present an approach that combines both turbulences. In the vicinity of a military test range and 120 m high wind turbines a new Doppler LIDAR system (WINDCUBETM v200s, Leosphere, France) was operated to investigate the vertical distribution of turbulent kinetic energy and the spatial distribution of the radial wind speed in the atmospheric boundary layer. Deployments in different modes were carried out to get best estimations of turbulence. Vertical profile measurements obtained with two ultrasonic anemometers at discrete levels on an 80 m high mast close to the position of the LIDAR were used for comparison. We present an adapted algorithm to calculate the TKE from a low-frequency signal (vertical profile every 10 s) and a approach to calculate C2n. The first preliminary results show a good agreement. Results on diurnal cycles of the TKE in different stability regimes and local effects will be discussed.

Infrared imaging of the sea surface is used for many purposes, such as remote sensing of large oceanographic structures, environmental monitoring, surveillance applications and platform signature research. Many of these studies rely on determining the contrast of a target feature with its background and therefore benefit from accurately predicting the signature of the underlying sea surface background. We here present a model that synthesizes infrared spectral images of sea surfaces. This model traces explicitly the behaviour of the sea wave structure and light propagation. To self-consistently treat spatial and temporal correlations of the clutter, geometrical realizations of sea surfaces are built based on realistic sea wave spectra and their temporal behaviour is subsequently followed. A camera model and a ray tracer are used to determine which parts of the sea surface are observable by individual camera pixels. Atmospheric input elements of the model, being sky dome, path radiance and transmission, are computed with MODTRAN for a chosen atmosphere.

High frequency fluctuations in the refractive index are the main atmospheric influence on wave propagation in the atmosphere. They are caused mainly from variations in atmospheric temperature. Ultrasonic anemometers have been established as common tools in performing in-situ measurements of turbulence. They were used as fixed point instruments from towers, for the characterization of local turbulence or from mobile platforms. Besides wind velocity fluctuations, high frequency variations of the sonic temperature are analyzed. Time series of temperature data are analyzed to derive the structure function of temperature CT 2, that should be proportional the strength of optical turbulence Cn 2. The application of the Fast Fourier transformation, temporal resolution and averaging time are addressed to show the applicability of ultrasonic anemometers. Also the influence of humidity fluctuations on the determination of Cn 2 in applications over land and over the sea is discussed. Errors in the applications from fixed points as well as from mobile platforms are estimated for different types of anemometers.

Using seasonally averaged meteorological and spectrally resolved aerosol profiles extracted from a maritime environment, this paper investigated how the resolution of the vertical profiles influences the 3-5μm and 8-12μm average transmittance and integrated path radiance computations conducted by MODTRAN in high-elevation scenarios. First, the minimum altitude to which the atmosphere should be defined in order to accurately determine the transmittance and path radiance along vertical and slant paths was investigated by recursively removing vertical layers until the relative changes in the transmittance and path radiance became smaller than those due to instrument uncertainty. Once this minimum height was found, the vertical resolution in the atmosphere below the minimum altitude was systematically varied. The suitability of several gradient-based criteria has been investigated to determine the optimal discretization of the vertical profiles. The results indicate that, depending on the quantity to be calculated, vertical discretizations based on the gradient in either the pressure, temperature or humidity serve as optimal discretizations in maritime high-elevation scenarios. Moreover, the followed methodology demonstrates how to adaptively implement a vertical resolution in a generic atmosphere, which generates crucial knowledge in supporting signature and sensor performance modelling for high-elevation scenarios.

BackgroundMultiple sclerosis (MS) is a chronic disorder of the central nervous system with an unpredictable disease course. Life partners often become caregivers, which can be both rewarding and challenging, as the caregiver's physical and mental health is often negatively affected. Previous studies on caregiver strain focused on caregivers of persons with MS with relatively high disability levels, while caregiver strain may already be experienced by life partners living with mildly disabled persons with MS.ObjectiveThe current study examines factors associated with caregiver strain in life partners of persons with mild disability due to relapsing-remitting MS.MethodsWe included 173 persons with relapsing-remitting MS (79% female; mean age 42.8 years; 90% employed; median EDSS 2.0) and their life partners. The life partners completed questionnaires on caregiver strain and neuropsychiatric and cognitive functioning of the person with MS. The persons with MS completed questionnaires about demographics, fatigue, personality, physical, cognitive and neuropsychiatric functioning, and underwent neuropsychological and neurological examinations. A linear regression analysis was conducted to examine predictors of caregiver strain.Results24% of the life partners experienced above average levels of caregiver strain. A multivariate linear regression analysis revealed that a higher age of the person with MS (β = 0.16, p = 0.04), more physical disability (β = 0.17 p = 0.04), more cognitive and neuropsychiatric problems of the person with MS as reported by the life partner (β = 0.33, p = 0.001) and higher severity of neuropsychiatric symptoms as reported by the life partner (β = 0.32, p = 0.001) were associated with higher caregiver strain (R2 = 0.49).ConclusionHigher caregiver strain in life partners of persons with mild disability due to relapsing-remitting MS was primarily associated with cognitive and neuropsychiatric problems of the person with MS.

Electro-optical and laser systems are operated world-wide. Their performance in the outside atmosphere is mainly governed by the strength of optical turbulence Cn2. The predictability of Cn2 using weather-forecast models is investigated by performing simulations with the Weather Research and Forecast Model (WRF). The WRF output data were combined with a micrometeorological parametrization to derive Cn2. Simulation runs were performed for locations and times included in our worldwide data set of Cn2 obtained in several field trials over land and over the sea. Experimental data of point and integrated path measurements in the surface layer were compared to model calculations of Cn2. The regions include different climatic conditions from South Africa, the US, as well as Central and Northern Europe. The applicability of WRF to predict Cn2 at the different locations will be discussed. It will be shown that WRF in a 1.1-km resolution is adequate to provide a first estimate of Cn2 © 2019 SPIE.

The aim of this paper is to determine an accurate formulation for the sea-spray source function characteristic for the North-Western Mediterranean. To this end, the MACMod aerosol transport model was implemented in the study area using different sea-state dependent flux formulations. The simulations were compared to a large data set of aerosol size distributions acquired over the last ten years in the study area, yielding the evolution of the sea-spray concentrations with increasing fetch and hence, with the development of the wave field. This allowed for an improvement of the Demoisson et al. (2013) sea-spray source function (S3F) for the Mediterranean. The new formulation extends its validity to shorter fetch and larger radii and turned out to be most suitable for predicting the atmospheric concentrations of sea-spray aerosols in this region. © 2018 Elsevier Ltd

The atmospheric influence on wave propagation was investigated during the First European South African Transmission ExpeRiment from June 2015 to February 2016. The focus in this article was set on optical turbulence, the main atmospheric factor affecting the position and strength of Laser beams, the performance of electro-optical systems and imaging. Measurements were performed continuously during the campaign on three sites over the northwestern part of False Bay. The optical turbulence measurements include in situ measurements using an ultrasonic anemometer at the Roman Rock Island. Integrated optical turbulence measurements were performed at two sites, over a path of 1.8 km and a long distance path of 8.6 km. The sites may be affected by local effects of the coastal environment. For comparison, the optical turbulence was modeled using micrometeorological parameterization. Additionally, the optical turbulence was determined by simulations using the weather research and forecast model WRF. Simulation results were compared to measurements considering seasonal and meteorological variations. The representativeness of the measurements locations for offshore measurements will be discussed. © 2018 SPIE.

BACKGROUND: The aim of this study was to examine whether work capabilities differ between workers with Multiple Sclerosis (MS) and workers from the general population. The second aim was to investigate whether the capability set was related to work and health outcomes.METHODS: A total of 163 workers with MS from the MS@Work study and 163 workers from the general population were matched for gender, age, educational level and working hours. All participants completed online questionnaires on demographics, health and work functioning. The Capability Set for Work Questionnaire was used to explore whether a set of seven work values is considered valuable (A), is enabled in the work context (B), and can be achieved by the individual (C). When all three criteria are met a work value can be considered part of the individual's 'capability set'.RESULTS: Group differences and relationships with work and health outcomes were examined. Despite lower physical work functioning (U = 4250, p = 0.001), lower work ability (U = 10591, p = 0.006) and worse self-reported health (U = 9091, p ≤ 0.001) workers with MS had a larger capability set (U = 9649, p ≤ 0.001) than the general population. In workers with MS, a larger capability set was associated with better flexible work functioning (r = 0.30), work ability (r = 0.25), self-rated health (r = 0.25); and with less absenteeism (r = - 0.26), presenteeism (r = - 0.31), cognitive/neuropsychiatric impairment (r = - 0.35), depression (r = - 0.43), anxiety (r = - 0.31) and fatigue (r = - 0.34).CONCLUSIONS: Workers with MS have a larger capability set than workers from the general population. In workers with MS a larger capability set was associated with better work and health outcomes.TRIAL REGISTRATION: This observational study is registered under NL43098.008.12: 'Voorspellers van arbeidsparticipatie bij mensen met relapsing-remitting Multiple Sclerose'. The study is registered at the Dutch CCMO register ( https://www.toetsingonline.nl ). This study is approved by the METC Brabant, 12 February 2014. First participants are enrolled 1st of March 2014.

Background Biologics are effective for treating symptoms in patients (pts) with active spondyloarthritis (SpA) and a number of drugs are available with different working mechanisms, and mode and interval of administration for this indication. Starting/switching a specific biologic occurs for various reasons. It is increasingly advocated to involve pts in treatment decisions. Pts can have various needs and expectations when involved in shared decision making. Objectives To explore which pts factors contributed to starting or switching biologics in SpA, how pts experienced shared decision making in this process, and the needs of pts starting biologics. Methods Pts with SpA were recruited from the rheumatology department, Maastricht University Medical Centre. In semi-structured focus group interviews pts were asked to elaborate on when and why biologics were started and switched and if they were involved in the treatment decision. A decision aid for rheumatoid arthritis (RA) biologics was shown and pts were asked if they consider a similar decision aid for SpA as valuable. Interviews were audiotaped, transcribed and analysed in NVIVO11 software. Results In total, 14 pts with SpA participated in 4 focus group interviews. Three pts were diagnosed with axial SpA, 5 pts with peripheral SpA and 6 pts were diagnosed with axial- and peripheral SpA, with or without concomitant extra-articular manifestations. Mean age was 62 years (range 41–77 years), 10 were female (62.5%). Average time since diagnoses was 28 years. Pts started on average 7.3 years (range 1–14 years) ago with their first biologic. Six pts used 1 biologic, 5 pts had switched once or twice, and 3 pts switched more than 3 times. Factors contributing to starting a first biologic were disease activity, fatigue, intolerance to prior medication, and ineffectiveness of prior medication. Two pts were included in a biological trial. Factors contributing to switching were adverse effects and ineffectiveness of prior biologic. Most pts were not involved in decision making when biologics were started or could not remember this. Some pts mentioned that only one or limited options were available at the time of start, and that the decision to start was made by the rheumatologist. However, also when more agents became available, decision for a specific biological was often made by the rheumatologist without discussing treatment options. Pts underlined the importance of how care providers offer a treatment decision. When the decision was offered as a suggestion, “Shall we do.”, it was experienced more pleasurable then when the decision was offered as a command, “Let ‘s do.”. All pts expressed their wish to develop a decision aid in which clear information about each biologic is provided on mode of administration, interval, and effect on different SpA features. One pt explicitly stated that he did not want to be actively involved in decision making, but preferred that the care provider decides. Conclusions When involving SpA pts in shared decision making on start/switching of a biological, information on effectiveness on disease activity, fatigue, adverse events as well as expected duration of effectiveness should be provided, in addition to modes of administration and interval of each agent. A decision aid can support pts in this. Disclosure of Interest None declared

Here, we investigate separately the dependence of the mixing time on the size and velocity of micro-droplets moving through serpentine channels. We find that the mixing time scales linearly with droplet size. All experimental data collapse on a master-line, when the convective time scale is multiplied by the dimensionless droplet size.

OBJECTIVE: To determine whether second-trimester cervical length (CL) in women with a twin pregnancy is associated with the risk of emergency Cesarean section. METHODS: This was a secondary analysis of two randomized trials conducted in 57 hospitals in The Netherlands. We assessed the univariable association between risk indicators, including second-trimester CL in quartiles, and emergency Cesarean delivery using a logistic regression model. For multivariable analysis, we assessed whether adjustment for other risk indicators altered the associations found in univariable (unadjusted) analysis. Separate analyses were performed for suspected fetal distress and failure to progress in labor as indications for Cesarean section. RESULTS: In total, 311 women with a twin pregnancy attempted vaginal delivery after 34 weeks' gestation. Emergency Cesarean delivery was performed in 111 (36%) women, of which 67 (60%) were performed owing to arrest of labor. There was no relationship between second-trimester CL and Cesarean delivery (adjusted odds ratio (aOR): 0.97 for CL 26(th) -50(th) percentiles; 0.71 for CL 51(st) - 75(th) percentiles; and 0.92 for CL > 75(th) percentile, using CL ≤ 25(th) percentile as reference). In multivariable analysis, the only variables associated with emergency Cesarean delivery were maternal age (aOR, 1.07 (95% CI, 1.00-1.13)), body mass index (BMI) (aOR, 3.99 (95% CI, 1.07-14.9) for BMI 20-23 kg/m(2) ; 5.04 (95% CI, 1.34-19.03) for BMI 24-28 kg/m(2) ; and 3.1 (95% CI, 0.65-14.78) for BMI > 28 kg/m(2) ) and induction of labor (aOR, 1.92 (95% CI, 1.05-3.5)). CONCLUSION: In nulliparous women with a twin pregnancy, second-trimester CL is not associated with risk of emergency Cesarean delivery. Copyright © 2014 ISUOG. Published by John Wiley & Sons Ltd.

Atmospheric turbulence impacts on the propagation of electro-optical radiation. Typical manifestations of optical turbulence are scintillation (intensity fluctuations), beam wander and (for laser systems) reduction of beam quality. For longer propagation channels, it is important to characterize the vertical and horizontal distribution (inhomogeneity) of the optical turbulence. In the framework of the First European South African Transmission ExpeRiment (FESTER) optical turbulence was measured between June 2015 and February 2016 on a 2 km over-water link over False Bay. The link ran from the Institute of Maritime Technology (IMT) in Simons Town to the lighthouse at Roman Rock Island. Three Boundary layer scintillometers (BLS900) allowed assessing the vertical distribution of optical turbulence at three different heights between 5 and 12 m above the water surface. The expected decrease of Cn 2 with height is not always found. These results are analyzed in terms of the meteorological scenarios, and a comparison is made with a fourth optical link providing optical turbulence data over a 8.7 km path from IMT to Kalk Bay, roughly 36° to the north of the three 2 km paths. The results are related to the inhomogeneous meteorological conditions over the Bay as assessed with the numerical weather prediction tool, the Weather Forecast and Research model WRF. © Copyright 2017 SPIE. The Society of Photo-Optical Instrumentation Engineers (SPIE)

A field trial was performed in the arid scrub area of White Sands, NM /USA in October 2017 investigating the atmospheric influence on imaging and sensor performance. In this paper we focus on the strength of optical turbulence. Optical turbulence is described by the structure function parameter of the refractive index Cn 2. It is responsible for beam wander, blurring. and scintillation. "Ground truth" measurements of optical turbulence were carried out using a Boundary Layer Scintillometer . The measurements were taken along an optical path of 3.64 km and a height of 1.5 m. Additionally, height dependency of Cn 2 is explored in the surface layer using 4 ultrasonic anemometers at discrete heights between 1 and 10 m. Power spectra of temperature were determined from time series of the ultrasonic anemometer data, which were inspected for the height dependency of spectral characteristics. The effect of the arid scrubs area on the applicability of Kolmogorov turbulence was investigated and discussed in this paper. © 2018 SPIE.

Binnen de tandheelkunde kunnen botulinetoxine en dermale fillers worden toegepast als aanvulling op de reeds bestaande therapiemogelijkheden. Botulinetoxine kent vooral veel functionele toepassingen, waarvan een tandarts gebruik kan maken om patienten van klachten af te helpen die op een andere wijze vaak lastig te bestrijden zijn. Daarnaast kan botulinetoxine worden toegepast voor esthetische toepassingen. De dermale fillers hebben vrijwel alleen esthetische toepassingen in het gezicht. Ook voor een tandarts kan het nuttig zijn om deze middelen toe te passen, wanneer meer harmonie in het gelaat dient te worden bereikt.

Operation and design of electro-optical systems are affected by atmospheric turbulence, quantified by refractive structure function parameter Cn 2. The long-term VerTurM experiment at a rural site in Northwestern Germany served to collect an extended dataset of vertical profiles of Cn 2 values up to 64 meters, completed by a characterization of the surface layer meteorology. A micrometeorological model in terms of the Monin-Obukhov similarity theory (MOST) was developed to predict the values of Cn 2 and its results were compared to the measurements. © Copyright 2017 SPIE. The Society of Photo-Optical Instrumentation Engineers (SPIE)

This paper reviews three phenomena that affect the propagation of electro-optical radiation through the atmosphere: absorption and scattering, refraction and turbulence. The net effect on imaging or laser systems is a net reduction of the effective range, or a degradation of the information contained in the electro-optical radiation. Recent advances in techniques to assess the concentration and composition of atmospheric aerosols, and to assess the strength of optical turbulence are discussed in more detail. © 2017 SPIE. The Society of Photo-Optical Instrumentation Engineers (SPIE)

The knowledge of the optical contrast of an oil layer on the sea under various surface roughness conditions is of great interest for oil slick monitoring techniques. This paper presents a 3D simulation of a dynamic sea surface contaminated by a floating oil film. The simulation considers the damping influence of oil on the ocean waves and its physical properties. It calculates the radiance contrast of the sea surface polluted by the oil film in relation to a clean sea surface for the SWIR spectral band. Our computer simulation combines the 3D simulation of a maritime scene (open clear sea/clear sky) with an oil film at the sea surface. The basic geometry of a clean sea surface is modeled by a composition of smooth wind driven gravity waves. Oil on the sea surface attenuates the capillary and short gravity waves modulating the wave power density spectrum of these waves. The radiance of the maritime scene is calculated in the SWIR spectral band with the emitted sea surface radiance and the specularly reflected sky radiance as components. Wave hiding and shadowing, especially occurring at low viewing angles, are considered. The specular reflection of the sky radiance at the clean sea surface is modeled by an analytical statistical bidirectional reflectance distribution function (BRDF) of the sea surface. For oil at the sea surface, a specific BRDF is used influenced by the reduced surface roughness, i.e., the modulated wave density spectrum. The radiance contrast of an oil film in relation to the clean sea surface is calculated for different viewing angles, wind speeds, and oil types characterized by their specific physical properties. © 2017 SPIE. The Society of Photo-Optical Instrumentation Engineers (SPIE)

A 72-year-old woman who recently had been treated with metronidazole presented with subacute dysarthria, gait ataxia and encephalopathy with severe anxiety. Head MRI showed symmetrical T2-hyperintensities. Under suspicion of a metronidazole-induced encephalopathy, metronidazole was stopped immediately. The patient recovered completely and follow-up MRI showed complete resolution of T2-hyperintensities.

Electro-optical and laser systems are presently deployed in naval operations around the world. The performance of these systems is negatively affected by optical turbulence in the atmosphere, quantified by the parameter Cn 2. The strength of the integrated optical turbulence Cn 2 was investigated for several coastal locations in different climatic conditions: False Bay (South Africa), the Baltic Sea (Bay of Eckernförde, Germany), the Mediterranean Sea (Crete, Greece), the Gulf of Mexico (Dauphin Island, Alabama, US), and the Arabian Gulf. The over-water, near-surface turbulence was characterized along paths that typically spanned 1.5 - 8.7 km using large aperture scintillometers. The dependency of Cn 2 on the air-sea surface temperature difference and wind speed is discussed, and the results for the five geographic regions are compared and discussed in terms of environmental conditions and climate. © Copyright 2017 SPIE. The Society of Photo-Optical Instrumentation Engineers (SPIE)

International audience; Sea-salt aerosol concentrations in the coastal zone are assessed with the numerical aerosol-transport model MACMod that applies separate aerosol source functions for open ocean and the surf zone near the sea–land transition. Numerical simulations of the aerosolconcentration as a function of offshore distance from the surf zone compare favourably with experimental data obtained during a surf zone aerosol experiment in Duck, North Carolina in autumn 2007. Based on numerical simulations, the effect of variations in aerosol production (source strength) and transport conditions (wind speed, air–sea temperature difference), we show that the surf-zone aerosols are replaced by aerosols generated over the open ocean asthe airmass advects out to sea. The contribution from the surf generated aerosol is significant during high wind speeds and high wave events, and is significant up to 30 km away from the production zone. At low wind speeds, the oceanic component dominates, except within 1–5 km of the surf zone. Similar results are obtained for onshore flow, where no further sea-salt aerosol production occurs as the airmass advects out over land. The oceanic aerosols that are well-mixed throughout the boundary layer are then more efficiently transported inland than are the surf-generated aerosols, which are confined to the first few tens of metres above the surface, and are therefore also more susceptible to the type of surface (trees or grass) that determines the deposition velocity.

A transmission experiment has been performed over an optical path of 1.53 km at a rural test site in Meppen, Northwest Germany. Direct transmission measurements were made by a 7-wavelength transmissometer. Transmission was further estimated from the average voltage received by a BLS2000 scintillometer, and evaluated with Mie theory from in-situ aerosol measurements near the optical path. Furthermore, the transmission was modeled with MODTRAN, driven with local meteorology, visibility and the rural aerosol model. For a central wavelength of 0.88μm, the transmissometer, the BLS200 and MODTRAN agree well. Remaining differences may be due to water transmission and continuum around 0.95μ;m that is picked up by the transmissometer and not by the narrow-banded BLS2000 and MODTRAN calculations. When MODTRAN is run without an aerosol model, or when this model is driven by a "default" visibility, the overlap with the measurements is extremely poor. © 2016 SPIE. The Society of Photo-Optical Instrumentation Engineers (SPIE)

The First European South African Experiment (FESTER) was conducted over about a 10 month period at the Institute of Maritime Technology (IMT) in False Bay, South Africa. One of the important goals was to validate atmospheric refraction and turbulence models. To achieve this goal it was required to measure the vertical profile of meteorological parameters and compare this to model predictions. A special helium kite balloon (Helikite) was used as lifting device for weather and temperature sensors to obtain a measured vertical air profile. This measurement was conducted in the middle of the atmospheric path for the principal electro-optic transmission link monitoring equipment (i.e. scintillometer and multi-spectral radiometer-transmissometer system). First results will focus on the vertical air temperature profile shape as function of general environmental conditions and the comparison to model predictions. © 2016 SPIE. The Society of Photo-Optical Instrumentation Engineers (SPIE)

Optical turbulence for over-water conditions was investigated in a long-term experiment over False Bay near Cape Town, South Africa. A sonic anemometer and two boundary-layer scintillometers were deployed to access in-situ turbulence as well as the integrated turbulence over two 1.8 and 8.7 km paths. Statistical analysis reveals spatial temporal variations of the turbulence conditions over False Bay, which might be related to differences in the atmospheric conditions and/or the surface (water) temperatures. An analysis in terms of mechanical and thermal forcing reveals that the latter factor is more dominant in determining the turbulence strength. © 2016 SPIE. The Society of Photo-Optical Instrumentation Engineers (SPIE)

We fabricated arrays of cantilever sensors suspended deep inside fluid wells. To eliminate critical alignment and assembling steps during encapsulation of the cantilevers, these 3-D MEMS devices are realized in a single-side, single-wafer process by employing photolithography on bulk micromachined substrates. Silicon nitride cantilevers with varying geometries are suspended up to [email protected] below the wafer surface, and a structured gold layer is patterned on top. After calibrating the cantilevers in an optical lever setup, the formation of a DNA monolayer on the cantilever surface is detected.

In piezoelectric positioning systems the achievable bandwidth is often limited by weakly damped resonant modes. System performance may be improved by avoiding the excitation of these modes. If sufficient mechanical damping is present this can be done by shifting resonant modes towards anti-resonant modes through manipulation of the mechanical boundary conditions. In a second approach the anti-resonances may be shifted towards the resonances by the application of modal actuation. Using this method the excitation of the second and higher order modes can be avoided by adjusting the distribution of actuation forces. This paper investigates and compares the application of modal control techniques in systems that are based on piezoelectric tube actuators such as atomic force microscopes.

Weather Research and Forecasting (WRF) model predictions using different boundary layer schemes and horizontal grid spacings were compared with observational and numerical large-eddy simulation data for conditions corresponding to a dry atmospheric convective boundary layer (CBL) over the southern Great Plains (SGP). The first studied case exhibited a dryline passage during the simulation window, and the second studied case was used to examine the CBL in a post-cold-frontal environment. The model runs were conducted with three boundary layer parameterization schemes (Yonsei University, Mellor–Yamada–Janjić, and asymmetrical convective) commonly employed within the WRF model environment to represent effects of small-scale turbulent transport. A study domain was centered over the Atmospheric Radiation Measurement Program SGP site in Lamont, Oklahoma. Results show that near-surface flow and turbulence parameters are predicted reasonably well with all tested horizontal grid spacings (1, 2, and 4 km) and that value added through refining grid spacing was minimal at best for conditions considered in this study. In accord with this result, it was suggested that the 16-fold increase in computing overhead associated with changing from 4- to 1-km grid spacing was not justified. Therefore, only differences among schemes at 4-km spacing were presented in detail. WRF model predictions generally overestimated the contribution to turbulence generation by mechanical forcing over buoyancy forcing in both studied CBL cases. Nonlocal parameterization schemes were found to match observational data more closely than did the local scheme, although differences among the predictions with all three schemes were relatively small.

In this paper a new contactless transport system for thin, flat products, such as silicon wafers, is introduced. The product is carried on a thin aerostatic film between the product and the transport system and transported along the system using viscous traction on the product surface. This viscous traction is the result of pressure driven air flow in an array of actuator cells. Several possible industrial applications are discussed, followed by an explanation of the operating principles. Furthermore an analytical model of the system is presented, together with computational results. Numerical modeling using FEA, solving for the incompressible Navier–Stokes equations, shows results that are in good agreement with the described analytical model and some experimental results. The maximum acceleration and vertical bearing stiffness that can be obtained for the considered actuator geometry meet the requirements for the considered industrial applications.

Summary Objective Delirium is a frequent and serious problem in the Intensive Care Unit (ICU). Several international guidelines recommend daily monitoring for ICU-delirium. The purpose of this article is to give an up-to-date overview of the current status of monitoring and treatment of ICU-delirium in the Netherlands. Design Nation-wide, telephone-based questionnaire survey. Participants Head nurse of all ICUs and a random sample of intensivists. Results Only 14% (n = 14) of all Dutch ICUs (n = 103) monitored for ICU-delirium. Of these, only half (7%) used a tool that is validated in ICU patients. In 31% of Dutch ICUs, a protocol was used to treat ICU-delirium. Responses were obtained from 100% of ICUs. Conclusion Despite an international guideline, not more than 7% of ICUs in our study routinely evaluated the presence of delirium with a validated instrument. Fewer than one-third of Dutch ICUs use a protocol to treat ICU-delirium.