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In this study, NO x and particle number concentration (PNC) at an urban background and a traffic location were measured in the city of Amsterdam (the Netherlands). Modelled and measured contributions to NO x and PNC at the traffic location were used to derive real-world PN emission factors for average urban road traffic. The results for NO x were applied to validate our approach. The real-world PN emission factors (#.km −1 ) were 2.9E+14 (urban road) and 3E+14 (motorway). These values were at least a factor eight higher than dynamometer-based PN emission factors from COPERT 4 and HBEFA databases. The real-world PN emission factors were used to model the contribution to PNC near road traffic in 2014. This was two to three times higher than the PNC urban background along urban roads over 20,000 vehicles per day and near motorways. The discrepancy between dynamometer-based and real-world emission factors demonstrates the need for more PNC observations to assess actual PN emissions from road traffic. [ABSTRACT FROM AUTHOR]

Total and size-resolved particle number and black carbon concentrations were investigated in urban areas of the city of Rotterdam (the Netherlands) situated near an industrial area. Several monitoring campaigns were conducted in the period 2011–2014 at three local locations and at a regional background site. Black carbon levels showed minor elevation due to industrial emissions. In contrast, particle number concentrations (PNC) increased during periods with wind directions from the industrial area, by 1000 to 23,000 particles per cm 3 depending on the distance to the area from 1 to 40 km. The size distribution of elevated PNC was characterized by two modes: 10–20 nm (nucleation particles) and 20–100 nm (Aitken particles). Five dominant industrial sources were identified and used as input for dispersion modelling of PN in 2012. The results showed that in Rotterdam about 70,000 addresses were exposed to an additional annual PNC of 5000–10,000 particles per cm 3 and about 55,000 addresses to additional PNC of 10,000–20,000 particles per cm 3 for 39% of the time. More measurements of PNC up- and downwind of the industrial area are recommended to identify more accurately the PN emission sources and to validate the dispersion modelling. [ABSTRACT FROM AUTHOR]

The presence of black carbon, and size-resolved and total particle number concentrations (PNC) were investigated in the vicinity of Schiphol airport in the Netherlands, the fourth busiest airport in Europe. Continuous measurements were conducted between March and May 2014 at Adamse Bos, located 7 km from Schiphol, and in 2012 at Cabauw, a regional background site 40 km south of Schiphol. No significantly elevated black carbon levels were found near Schiphol. However, PNC increased during periods in which the wind direction was from Schiphol: at Cabauw by 20% and at Adamse Bos by a factor of three, from 14,100 (other wind directions) to 42,000 # cm −3 between 06.00 and 23.00. The size distribution of Schiphol-related PNC was dominated by ultrafine particles, ranging from 10 to 20 nm. Four relevant particle number (PN) emission sources at Schiphol were identified as being responsible for the elevated PNC levels at Adamse Bos: take-off and climb-out on the Kaagbaan and Aalsmeerbaan runways, planes waiting at the gates, and landing on the Buitenveldertbaan runway. PN emissions from road traffic at and near the airport were less important than air traffic. The exposure to Schiphol-related PNC in urban areas northeast of Schiphol in Amsterdam and Amstelveen was estimated for 2012 using a Gaussian Plume model. The results showed that a considerable number of the 555,000 addresses in the modelling domain were exposed to elevated PNC. For example: 45,000 addresses suffered long-term exposure to an additional annual background PNC of 5–10,000 # cm −3 originating from Schiphol and 60,000 addresses suffered short-term exposure (14% of the time) of additional 10–15,000 # cm −3 originating from Schiphol. Further research on emission sources and the dispersion of PN is recommended and may support future studies on eventual health effects. [ABSTRACT FROM AUTHOR]

This study aims to quantify the impact of black carbon from inland shipping on air quality, expressed as elemental carbon (EC) near inland waterways in The Netherlands. Downwind measurements of particle numbers and EC were used to establish emission factors for EC from inland shipping using inverse modelling. These emission factors were combined with data on energy consumption to derive annual average emissions rates for all Dutch waterways. A line source model was applied to compute the contribution of inland shipping to annual average EC concentrations for around 140,000 people living within 200 m of busy waterways in The Netherlands. The results showed that they are exposed to additional EC concentrations of up to 0.5 µg EC per m³ depending on the shipping volume and distance from the waterway. In view of the envisaged growth in water transport, this underlines the need to reduce combustion emissions from inland shipping. Targeting "gross" polluters may be the most effective approach since 30% of ships cause more than 80% of the total emissions. [ABSTRACT FROM AUTHOR]

Abstract: The contribution of regional, urban and traffic sources to PM2.5 and PM10 in an urban area was investigated in this study. The chemical composition of PM2.5 and PM10 was measured over a year at a street location and up- and down-wind of the city of Rotterdam, the Netherlands. The 14C content in EC and OC concentrations was also determined, to distinguish the contribution from “modern” carbon (e.g., biogenic emissions, biomass burning and wildfires) and fossil fuel combustion. It was concluded that the urban background of PM2.5 and PM10 is dominated by the regional background, and that primary and secondary PM emission by urban sources contribute less than 15%. The 14C analysis revealed that 70% of OC originates from modern carbon and 30% from fossil fuel combustion. The corresponding percentages for EC are, respectively 17% and 83%. It is concluded that in particular the urban population living in street canyons with intense road traffic has potential health risks. This is due to exposure to elevated concentrations of a factor two for EC from exhaust emissions in PM2.5 and a factor 2–3 for heavy metals from brake and tyre wear, and re-suspended road dust in PM10. It follows that local air quality management may focus on local measures to street canyons with intense road traffic. [Copyright &y& Elsevier]

Quality of substitution voicing-i.e., phonation with a voice that is not generated by the vibration of two vocal folds-cannot be adequately evaluated with routinely used software for acoustic voice analysis that is aimed at 'common' dysphonias and nearly periodic voice signals. The AMPEX analysis program (Van Immerseel and Martens) has been shown previously to be able to detect periodicity in irregular signals with background noise, and to be suited for running speech. The validity of this analysis program is first tested using realistic synthesized voice signals with known levels of cycle-to-cycle perturbations and additive noise. Second, exhaustive acoustic analysis is performed of the voices of 116 patients surgically treated for advanced laryngeal cancer and recorded in seven European academic centers. All of them read out a short phonetically balanced passage. Patients were divided into six groups according to the oscillating structures they used to phonate. Results show that features related to quantification of voicing enable a distinction between the different groups, while the features reporting F-instability fail to do so. Acoustic evaluation of voice quality in substitution voices thus best relies upon voicing quantification. [ABSTRACT FROM AUTHOR]

Substitution voicing cannot be evaluated accurately by the GRBAS perceptual rating scale, and there is a need for a valuable alternative. Therefore, we developed and tried out a perceptual rating scale, consisting of five new parameters: impression, intelligibility, noise, fluency and voicing, each to be scored between 0 (very bad score) to 10 (very good score for a substitution voice). In analogy to the GRBAS scale, they are then converted to deviance scores ranging from 0 (similar to good substitution voicing) to 3 (very deviant from good substitution voicing). Inter-individual agreement measured in a set of 24 semi-professional jury members seemed to be moderate for all parameters. Mean figures of 0.52, 0.51, 0.46, 0.53 and 0.46 are obtained for the parameters impression, intelligibility, noise, fluency and voicing, respectively. Because a high correlation exists between the first two parameters (0.917) and relying on the correlation figures between the two “I”s and the other parameters (correlation values for “impression” vary from 0.79–0.86; values for “intelligibility” range from 0.74–0.83), we suggest to discard the parameter impression, which turns the actual IINFVo scale into INFVo. The proposed (I)INFVo perceptual rating scale seems promising for the assessment of substitution voicing. Eventual improvements and practical proposals are discussed. [ABSTRACT FROM AUTHOR]

Transsexualism implies that an anatomically normal individual feels that he or she is actually a member of the opposite sex. Treatment usually includes real-life experience along with hormone therapy and sex reassignment surgery. Voice modification surgery may be necessary, as pass ability in general is still in a large extent dependent on the aspects of voice in transsexual people. Often male-to-female patients report being addressed in telephone conversations as their genetic gender, which is experienced as a disability. The purpose of this study was to evaluate the impact of voice on the quality of life in transsexuals.In order to detect the disability caused by a voice disorder, the validated assessment method the Voice Handicap Inventory (VHI) was used. An additional question about the way patients were addressed in a telephone conversation was added.As part of a study describing general health in transsexual persons, done at the Ghent University Hospital Belgium, a total of 48 patients were evaluated. In female-to-male transsexuals the median scores were very low, suggesting testosterone treatment led to an acceptable voice alteration. A higher serum LH level was significantly correlated with higher total, functional and emotional VHI scores. In male-to-female transsexuals the scores were significantly higher than those of the female-to-male transsexuals, but still there was no indication of a real disability/handicap. The extra telephone question was scored higher suggesting male-to-female transsexuals did experience a disability caused by their voice. From this study it is concluded that the VHI values did not demonstrate a handicapping effect. [ABSTRACT FROM AUTHOR]

Spasmodic dysphonia voices form, in the same way as substitution voices, a particular category of dysphonia that seems not suited for a standardized basic multidimensional assessment protocol, like the one proposed by the European Laryngological Society. Thirty-three exhaustive analyses were performed on voices of 19 patients diagnosed with adductor spasmodic dysphonia (SD), before and after treatment with Botulinum toxin. The speech material consisted of 40 short sentences phonetically selected for constant voicing. Seven perceptual parameters (traditional and dedicated) were blindly rated by a panel of experienced clinicians. Nine acoustic measures (mainly based on voicing evidence and periodicity) were achieved by a special analysis program suited for strongly irregular signals and validated with synthesized deviant voices. Patients also filled in a VHI-questionnaire. Significant improvement is shown by all three approaches. The traditional GRB perceptual parameters appear to be adequate for these patients. Conversely, the special acoustic analysis program is successful in objectivating the improved regularity of vocal fold vibration: the basic jitter remains the most valuable parameter, when reliably quantified. The VHI is well suited for the voice-related quality of life. Nevertheless, when considering pre-therapy and post-therapy changes, the current study illustrates a complete lack of correlation between the perceptual, acoustic, and self-assessment dimensions. Assessment of SD-voices needs to be tridimensional. [ABSTRACT FROM AUTHOR]

Background: The following position statement from the Union of the European Phoniatricians, updated on 25th May 2020 (superseding the previous statement issued on 21st April 2020), contains a series of recommendations for phoniatricians and ENT surgeons who provide and/or run voice, swallowing, speech and language, or paediatric audiology services. Objectives: This material specifically aims to inform clinical practices in countries where clinics and operating theatres are reopening for elective work. It endeavours to present a current European view in relation to common procedures, many of which fall under the aegis of aerosol generating procedures. Conclusion: As evidence continues to build, some of the recommended practices will undoubtedly evolve, but it is hoped that the updated position statement will offer clinicians precepts on safe clinical practice. [ABSTRACT FROM AUTHOR]

A first direct intercomparison of aerosol vertical profiles from Multi-Axis Differential Optical Absorption Spectroscopy (MAX-DOAS) observations, performed during the Cabauw Intercomparison Campaign of Nitrogen Dioxide measuring Instruments (CINDI) in summer 2009, is presented. Five out of 14 participants of the CINDI campaign reported aerosol extinction profiles and aerosol optical thickness (AOT) as deduced from observations of differential slant column densities of the oxygen collision complex (O4) at different elevation angles. Aerosol extinction vertical profiles and AOT are compared to backscatter profiles from a ceilometer instrument and to sun photometer measurements, respectively. Furthermore, the near-surface aerosol extinction coefficient is compared to in situ measurements of a humidity-controlled nephelometer and dry aerosol absorption measurements. The participants of this intercomparison exercise use different approaches for the retrieval of aerosol information, including the retrieval of the full vertical profile using optimal estimation and a parametrised approach with a prescribed profile shape. Despite these large conceptual differences, and also differences in the wavelength of the observed O4 absorption band, good agreement in terms of the vertical structure of aerosols within the boundary layer is achieved between the aerosol extinction profiles retrieved by the different groups and the backscatter profiles observed by the ceilometer instrument. AOTs from MAX-DOAS and sun photometer show a good correlation (R>0.8), but all participants systematically underestimate the AOT. Substantial differences between the near-surface aerosol extinction from MAX-DOAS and from the humidified nephelometer remain largely unresolved. [ABSTRACT FROM AUTHOR]

The annual concentration of elemental carbon (EC) has been derived for The Netherlands in 2011. National emissions contribute 55% to the average EC concentration in the Netherlands. About 65% of the national contribution comes from emissions from road traffic and about 35% from other mobile sources (15%), households (14%), shipping (4%) and other combustion sources (2%). Conversion factors were established to compare different methods of EC measurement such as Black Smoke, Black Carbon and thermal analysis. The measured regional and urban background concentrations and variability were 0.5 ± 0.1 and 0.9 ± 0.1 μg EC per m3, respectively. The ratios between modelled and measured regional and urban background concentrations were 1.6 ± 0.5 and 1.8 ± 0.4, respectively. The modelled values are likely to be overestimated. The modelled and measured traffic contributions to EC concentrations near motorways and in street canyons were in the range 1.1–1.3 μg m−3 with total EC concentrations of 2.0 and 2.2 μg m−3, respectively. Our study showed that EC concentrations near intense traffic are increased with a factor 2–4 as compared to the urban and regional background, respectively. Consequently there is a similar variation in exposure and potential health effects in the population. More measurements of EC are required to improve modelling of EC concentrations in particular at urban background and near traffic locations. [ABSTRACT FROM AUTHOR]

The development of a radiation fog layer at the Cabauw Experimental Site for Atmospheric Research (51.97°N, 4.93°E) on 23 March 2011 was observed with ground-based in situ and remote sensing observations to investigate the relationship between visibility and radar reflectivity. The fog layer thickness was less than 200 m. Radar reflectivity values did not exceed −25 dB Z even with visibilities less than 100 m. The onset and evaporation of fog produce different radar reflectivity-visibility relationships. The evolution of the fog layer was modeled with a droplet activation model that used the aerosol size distribution observed at the 60-m altitude tower level as input. Radar reflectivity and visibility were calculated from model drop size spectra using Mie scattering theory. Since radiative cooling rates are small in comparison with cooling rates due to adiabatic lift of aerosol-laden air, the modeled supersaturation remains low so that few aerosol particles are activated to cloud droplets. The modeling results suggest that the different radar reflectivity-visibility relationships are the result of differences in the interplay between water vapor and cloud droplets during formation and evaporation of the fog. During droplet activation, only a few large cloud droplets remain after successfully competing for water vapor with the smaller activated droplets. These small droplets eventually evaporate (deactivate) again. In the fog dissolution/evaporation stage, only these large droplet need to be evaporated. Therefore, to convert radar reflectivity to visibility for traffic safety products, knowledge of the state of local fog evolution is necessary. [ABSTRACT FROM AUTHOR]

A small optical device has been constructed to determine aerosol total area concentrations from angular scattering. Particles in the open sample volume are irradiated by a pulsed laser diode. Radiation scattered at angles between 15° and 35° is detected by a photodiode. The amplified signals are processed with a sample/hold circuit. This instrument has been applied for measurements on sea spray aerosol near the air-sea interface. Wave-induced fluctuations were clearly demonstrated. Other applications are indicated. [ABSTRACT FROM AUTHOR]