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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.

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.

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.

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.

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.

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)

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)

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.

An overview is given of the First European - South African Transmission ExpeRiment (FESTER), which took place in South Africa, over the False Bay area, centered around Simon's Town. The experiment lasted from April 2015 through February 2016 and involved continuous observations as well as periodic observations that took place during four Intensive Observation Periods (IOPs) of 2 weeks each, which were spread over the year. The continuous observations aimed at a characterization of the electro-optical propagation environment, and included standard meteorology, aerosol, refraction and turbulence measurements. The periodic observations aimed at assessing the performance of electro-optical sensors in VIS / SWIR / MWIR and LWIR wavebands by following a boat sailing outbound and inbound tracks. In addition, dynamic aspects of electro-optical signatures, i.e., the changes induced by variations in the environment and/or target orientation, were studied. The present paper provides an overview of the trial, and presents a few first results. © 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 the establishment of the air-sea temperature difference (ASTD) homogeneity along the main propagation link atmospheric path since it is a basic assumption for most of the atmospheric turbulence models (caused by refractive index variations). The ASTD was measured from a small scientific work boat (called Sea Lab) moving along a straight in- and outbound track along the main propagation link path. The air temperature on-board was measured using standard weather sensors, while the sea surface temperature was measured using a long wavelength infrared radiometer, which was compared to the bulk sea temperature half a meter below the sea surface. This was obtained by an under water temperature sensor mounted on a â€surfboard' that was towed alongside Sea Lab. Vertical water temperature profiles were also measured along the main propagation path in order to determine the depth of the surface mixed layer and thermocline using a Conductivity Temperature Depth profiler (CTD). First results investigated the ASTD variation along the horizontal line-of-sight path used by the principal electro-optic transmission link monitoring equipment (i.e. scintillometer and multi-spectral radiometer-transmissometer system). © 2016 SPIE. The Society of Photo-Optical Instrumentation Engineers (SPIE)

A long term field trial called FESTER (First European South African Transmission Experiment) has been conducted by an international collaboration of research organizations during the course of almost one year at False Bay, South Africa. Main objectives of the experiment are a better insight into atmospherical effects on propagation of optical radiation, a deeper understanding of the effects of (marine) aerosols on transmission, and the connection of the mentioned effects to the general meteorological and oceanographic conditions/parameters. Modelling of wakes and possible infrared-radar synergy effects are further points of interest. The duration of one year ensures the coverage of most of the relevant meteorological conditions during the different seasons. While some measurements have been performed by permanent installations, others have been performed during intensive observation periods (IOP). These IOPs took place every two to three months to ensure seasonal changes. The IOPs lasted two weeks. We will give an overview of the general layout of the experiment and report on first results. An outlook on the planned analysis of the acquired data, which includes linkage to the Weather Research and Forecasting model (WRF), will be given. © 2016 SPIE. The Society of Photo-Optical Instrumentation Engineers (SPIE)

The experiment FESTER (First European South African Transmission ExpeRiment) took place in 2015 to investigate the atmospheric influence on electro-optical systems performance across False Bay / South Africa on a long term basis. Several permanent stations for monitoring electro-optical propagation and atmospheric parameters were set up around the Bay. Additional intensive observation periods (IOPs) allowed for boat runs to assess the inhomogeneous atmospheric propagation conditions over water. In this paper we focus on the distribution of optical turbulence over the Bay. The different impact of water masses originating from the Indian Ocean and the Benguela current on the development of optical turbulence is discussed. The seasonal behavior of optical turbulence is presented and its effect on electro-optical system performance examined. © 2016 SPIE. The Society of Photo-Optical Instrumentation Engineers (SPIE)

A comparison of aerosol data acquired at five different sites around the globe is presented. All data has been acquired with the same instrumentation and representative size distributions for marine air masses at 10 m/s wind speed have been selected for comparison. Differences in the concentrations of larger and smaller aerosols at the various sites are explained in terms of fetch, trade winds, shielding, pollution, seawater temperature and phytoplankton bloom. The differences in size distribution induce significant differences in the extinction coefficients from the VIS to the LWIR at the various sites. Consequently, the transmission over a specific range also varies significantly. This suggests that a detailed analysis of the conditions at each site is necessary in order to understand the exact aerosol behavior and to correctly predict electro-optical propagation effects due to aerosols. © 2016 SPIE. The Society of Photo-Optical Instrumentation Engineers (SPIE)

Background Job loss is common in multiple sclerosis (MS) and is known to exert a negative effect on quality of life. The process leading up to job loss typically includes negative work events, productivity losses and a need for accommodations. By using active coping strategies job loss may be prevented or delayed. Objective Our goal was to examine negative work events and accommodations in relation to coping strategies in employed relapsing–remitting MS patients. Methods Ninety-seven MS patients (77% females; 21–59 years old) completed questionnaires concerning the patient’s work situation, coping strategies, demographics, physical, psychological and cognitive functioning. Forward binary logistic regression analyses were conducted to examine coping strategies and other (disease) characteristics predictive of reported negative work events and accommodations. Results Nineteen per cent of the employed MS patients reported one or more negative work events, associated with a higher use of emotion-oriented coping and more absenteeism. Seventy-three per cent reported using one or more work accommodations, associated with a higher educational level and more presenteeism. MS patients reporting physical changes to the workplace employed more emotion-oriented coping, while flexible scheduling was associated with task-oriented coping. Conclusion Emotion-oriented and task-oriented coping strategies are associated with negative work events and the use of accommodations.

Application Service Providing (ASP), het op huurbasis aanbieden van software op afstand via bijvoorbeeld het internet, heeft het stadium bereikt dat het een serieuze optie wordt voor kleine en middelgrote ondernemers. Door hun brede inzetbaarheid en modulaire opbouw zijn applicaties voor de financiële administratie erg geschikt voor het ASP-model. In tegenstelling tot wat vaak wordt beweerd, is kostenbesparing in dit geval niet de belangrijkste reden om voor ASP te kiezen. Andere voordelen, zoals toegang tot de administratie vanuit meerdere locaties en nieuwe mogelijkheden tot samenwerking, spelen een grotere rol. ASP kan gevolgen hebben voor de bedrijfsvoering van een onderneming in het algemeen, en voor de samenwerking met de accountant in het bijzonder. Accountants ontdekken nieuwe vormen van dienstverlening gebaseerd op ASP, zoals het assisteren bij de financiële administratie op afstand. Daarnaast ontstaan er modellen waarbij de accountant fungeert als intermediair tussen ondernemer en de ASP.

A recent field trial in the Northern German littoral area of the Baltic Sea yielded a dataset of visibility, meteorological parameters, aerosol size distributions, as well as transmission over a horizontal path of 1344 m. The experimental results are compared to simulations using the MODTRAN (moderate resolution atmospheric transmission) model, that was run with the rural and Navy Aerosol Model, (NAM) in various configurations. Best results were obtained when MODTRAN was tuned with the measured visibility values. When NAM was used without visibility tuning, MODTRAN tended to overestimate the transmission in low-visibility conditions, which was attributed to the presence of a non-maritime aerosol fraction. © 2015 SPIE.

Our world is constantly changing, and this has its effect on worldwide military operations. For example, there is a change from conventional warfare into a domain that contains asymmetric threats as well. The availability of high-quality imaging information from Electro-Optical (EO) sensors is of high importance, for instance for timely detection and identification of small threatening vessels in an environment with a large amount of neutral vessels. Furthermore, Rules of Engagement often require a visual identification before action is allowed. The challenge in these operations is to detect, classify and identify a target at a reasonable range, while avoiding too many false alarms or missed detections. Current sensor technology is not able to cope with the performance requirements under all circumstances. For example, environmental conditions can reduce the sensor range in such a way that the operational task becomes challenging or even impossible. Further, limitations in automatic detection algorithms occur, e.g. due to the effects of sun glints and spray which are not yet well-modelled in the detection filters. For these reasons, Tactical Decision Aids will become an important factor in future operations to select the best moment to act. In this paper, we describe current research within The Netherlands on this topic. The Defence Research and Development Programme “Multifunctional Electro-Optical Sensor Suite (MEOSS)” aims at the development of knowledge necessary for optimal employment of Electro-Optical systems on board of current and future ships of the Royal Netherlands Navy, in order to carry out present and future maritime operations in various environments and weather conditions.

To determine whether second-trimester cervical length (CL) in women with a twin pregnancy is associated with the risk of emergency Cesarean section.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.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 CL75(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 BMI28 kg/m(2) ) and induction of labor (aOR, 1.92 (95% CI, 1.05-3.5)).In nulliparous women with a twin pregnancy, second-trimester CL is not associated with risk of emergency Cesarean delivery.

The SeaCluse computer code calculates the nonlinear interactions between sea spray droplet concentrations and the scalar fields of water vapor concentration and temperature in the marine atmospheric surface layer. The code simulates most of the dynamics of the evaporating sea spray droplets in the turbulent air flow over a wavy surface, the thelmodynamic transformations of the spray droplets, and the influence of the droplets on the structure of the lower marine atmosphere. The main processor computes along the vertical the horizontally averaged budgets of droplet concentration, water vapor concentration, and sensible heat, including the dynamic and thermodynamic air-droplet interactions. This paper presents the first simulations of evaporating sea spray droplets made with the SeaCluse model. It is shown that common assumptions such as exponential vertical concentration profiles and the evaporation of all droplets to their equilibrium radius do not necessarily hold for droplets with a radius larger than ~30 µm. The present results also demonstrate the importance of the nonlinear interactions between sea spray droplets and the scalar fields of water vapor and temperature. Most droplets evaporate close to the surface, in a layer of ~2-3 times the wave height. The impact of evaporating sea spray droplets increases rapidly with increasing wind speed.

Checking the functional equivalence of sequential circuits is an important practical problem. Because general algorithms for solving this problem require a state-space traversal of the product machine, they are computationally expensive. In this paper, we present a new method for sequential equivalence checking which utilizes functionally equivalent signals to prove the equivalence of both circuits, thereby avoiding the state-space traversal. The effectiveness of the proposed method is confirmed by experimental results on retimed and optimized ISCAS'89 benchmarks.

This paper presents GreyHound, a new methodology to improve cell placement of logic netlists in standard design flows by utilizing the regular structure of datapath circuitry. Key features of the methodology are automatic extraction of regular structures and utilization of regularity even after extensive logic optimization. The latter is important because logic optimization tends to introduce significant non-regularities even though the underlying structural regularity is largely preserved. In the proposed methodology, the structural regularity in the initial gate netlist produced by module generators is extracted automatically. This results in alignment specs for the regular logic, which are used to drive the subsequent placement of the netlist. After each customary iteration through placement and logic optimization, a logic correspondence extractor is used to identify functional correspondences between the optimized and the original netlist. Along these correspondences, the extracted structural alignment cell attributes are inherited from the initial to the optimized circuit so that its cells can be aligned accordingly.

In order to investigate the impact of plant physiology on emissions of biogenic volatile organic compounds monoterpene emission rates from Rosmarinus officinalis (L.) and Pistacia lentiscus (L.) and isoprene emission rates from Erica arborea (L.) and Myrtus communis (L.) were determined. The study, an activity in the framework of BEMA (Biogenic Emissions in the Mediterranean Area), was carried out in May 1994 at Castelporziano near Rome in Italy, using a dynamic enclosure technique combined with recording CO2 gas exchange, temperature and irradiance data. The monoterpenes dominating the emission pattern were 1,8-cineol, α-pinene and β-pinene for rosemary and α-pinene, linalool and β-pinene + sabinene for pistachio. Total monoterpene emission rates standardized to 30°C of 1.84 ± 0.24 and 0.35 ± 0.04 μg Cg−1 dw h−1 were found for rosemary and pistachio, respectively (on a leaf dry weight basis). Myrtle emitted 22.2 ± 4.9 μg C g−1 dw h−1 at standard conditions (30°C, PAR 1000 μmol photons m−2 s−1 as isoprene and erica 5.61 μg C g−1 dw h−1 The carbon loss due to terpenoid emissions per photosynthetically carbon uptake was about 0.01–0.1% for the monoterpene emitters. The isoprene emitting shrubs lost 0–0.9% of the assimilated carbon. The rapid induction of emissions in the sun after temporary shading indicates that isoprene emissions were closely linked to photosynthesis. A higher proportion of the assimilated carbon was lost as isoprene under conditions of high light and temperature compared to the morning and evening hours.

Delirium is a common disorder in intensive care unit (ICU) patients. It is unclear whether ICU environment affects delirium. We investigated the influence of ICU environment on the number of days with delirium during ICU admission. In this prospective before–after study, ICU delirium was compared between a conventional ICU with wards and a single-room ICU with, among others, improved daylight exposure. We included patients admitted for more than 24 h between March and June 2009 (ICU with wards) or between June and September 2010 (single-room ICU). Patients who remained unresponsive throughout ICU admission were excluded. The presence of delirium in the preceding 24 h was assessed daily with the confusion assessment method for the ICU (CAM-ICU) by research physicians combined with evaluation of medical and nursing charts. The number of days with delirium was investigated with Poisson regression analysis. We included 55 patients (449 observation days) in the ICU with wards and 75 patients (468 observation days) in the single-room ICU. After adjusting for confounding, the number of days with delirium decreased by 0.4 days (95 % confidence interval 0.1–0.7) in the single-room ICU (p = 0.005). The incidence of delirium during ICU stay was similar in the ICU with wards (51 %) and in the single-room ICU (45 %, p = 0.53). This study is the first to show that ICU environment may influence the course of delirium in ICU patients.

Item does not contain fulltext RATIONALE: Delirium is often unrecognized in ICU patients and associated with poor outcome. Screening for ICU delirium is recommended by several medical organizations to improve early diagnosis and treatment. The Confusion Assessment Method for the ICU (CAM-ICU) has high sensitivity and specificity for delirium when administered by research nurses. However, test characteristics of the CAM-ICU as performed in routine practice are unclear. OBJECTIVES: To investigate the diagnostic value of the CAM-ICU in daily practice. METHODS: Teams of three delirium experts including psychiatrists, geriatricians, and neurologists visited 10 ICUs twice. Based on cognitive examination, inspection of medical files, and Diagnostic and Statistic Manual of Mental Disorders, 4th edition, Text Revision criteria for delirium, the expert teams classified patients as awake and not delirious, delirious, or comatose. This served as a gold standard to which the CAM-ICU as performed by the bedside ICU-nurses was compared. Assessors were unaware of each other's conclusions. MEASUREMENTS AND MAIN RESULTS: Fifteen delirium experts assessed 282 patients of whom 101 (36%) were comatose and excluded. In the remaining 181 (64%) patients, the CAM-ICU had a sensitivity of 47% (95% confidence interval [CI], 35%-58%); specificity of 98% (95% CI, 93%-100%); positive predictive value of 95% (95% CI, 80%-99%); and negative predictive value of 72% (95% CI, 64%-79%). The positive likelihood ratio was 24.7 (95% CI, 6.1-100) and the negative likelihood ratio was 0.5 (95% CI, 0.4-0.8). CONCLUSIONS: Specificity of the CAM-ICU as performed in routine practice seems to be high but sensitivity is low. This hampers early detection of delirium by the CAM-ICU.