Modelling of the natural chlorine cycling in a coniferous stand: implications for chlorine-36 behaviour in a contaminated forest environment

Considered as one of the most available radionuclide in soileplant system, 36Cl is of potential concern for long-term management of radioactive wastes, due to its high mobility and its long half-life. To evaluate the risk of dispersion and accumulation of 36Cl in the biosphere as a consequence of a potential contamination, there is a need for an appropriate understanding of the chlorine cycling dynamics in the ecosystems. To date, a small number of studies have investigated the chlorine transfer in the ecosystem including the transformation of chloride to organic chlorine but, to our knowledge, none have modelled this cycle. In this study, a model involving inorganic as well as organic pools in soils has been developed and parameterised to describe the biogeochemical fate of chlorine in a pine forest. The model has been evaluated for stable chlorine by performing a range of sensitivity analyses and by comparing the simulated to the observed values. Finally a range of contamination scenarios, which differ in terms of external supply, exposure time and source, has been simulated to estimate the possible accumulation of 36Cl within the different compartments of the coniferous stand. The sensitivity study supports the relevancy of the model and its compartments, and has highlighted the chlorine transfers affecting the most the residence time of chlorine in the stand. Compared to observations, the model simulates realistic values for the chlorine content within the different forest compartments. For both atmospheric and underground contamination scenarios most of the chlorine can be found in its organic form in the soil. However, in case of an underground source, about two times less chlorine accumulates in the system and proportionally more chlorine leaves the system through drainage than through volatilisation

Willem Bilderdijk: paixão italiana, amor holandês

Tradução de: Sien Van Den Hoof

Compliance With Legal Age Restrictions on Adolescent Alcohol Sales for Alcohol Home Delivery Services (AHDS)

Purpose: Alcohol availability is an important predictor of alcohol use in adolescents and its negative consequences. Within this study, we zoomed in on availability through alcohol home delivery services (AHDS) by measuring compliance with the legal age limit in this sector. Methods: Two methods were used: (1) mystery shopping in which 21 underage AHDS beer orders were placed and received and (2) mystery calls in which 30 AHDS were called and questioned. Results: In the mystery shopping study, all 21 deliveries were approved and executed by the AHDS (compliance 0%). Within the mystery calls, 23 AHDS said they would not sell alcohol to 15-year-olds (76.7% self-reported compliance), but 19 of them approved secondary purchasing. In total, self-reported compliance was only found in 4 out of the 30 AHDS (13.3%). Conclusions: In addition to supermarkets, liquor stores, and the catering industry, AHDS should not be overlooked. Low (or no) compliance with age limits in AHDS is a weak link in the system of underage alcohol availabilit

Low power wireless sensor network for building monitoring

A wireless sensor network is proposed for monitoring buildings to assess earthquake damage. The sensor nodes use custom-developed capacitive MEMS strain and 3D acceleration sensors and a low power readout ASIC for a battery life of up to 12 years. The strain sensors are mounted at the base of the building to measure the settlement and plastic hinge activation of the building after an earthquake. They measure periodically or on-demand from the base station. The accelerometers are mounted at every floor of the building to measure the seismic response of the building during an earthquake. They record during an earthquake event using a combination of the local acceleration data and remote triggering from the base station based on the acceleration data from multiple sensors across the building. A low power network architecture was implemented over an 802.15.4 MAC in the 900MHz band. A custom patch antenna was designed in this frequency band to obtain robust links in real-world conditions

Age-friendly cities in the Netherlands: An explorative study of facilitators and hindrances in the built environment and ageism in design

The World Health Organization (WHO) strives to assist and inspire cities to become more ‘age-friendly’ through the Global Age-Friendly Cities Guide. An age-friendly city offers a supportive environment that enables residents to grow older actively within their families, neighbourhoods and civil society, and offers extensive opportunities for their participation in the community. In the attempts to make cities age-friendly, ageism may interact with these developments. The goal of this study was to investigate the extent to which features of age-friendly cities, both facilitators and hindrances, are visible in the city scape of the Dutch municipalities of The Hague and Zoetermeer and whether or not ageism is manifested explicitly or implicitly. A qualitative photoproduction study based on the Checklist of Essential Features of Age-Friendly Cities was conducted in five neighbourhoods. Both municipalities have a large number of visual age-friendly features, which are manifested in five domains of the WHO model, namely Communication and information; Housing; Transportation; Community support and health services; and Outdoor spaces and buildings. Age-stereotypes, both positive and negative, can be observed in the domain of Communication and information, especially in the depiction of third agers as winners. At the same time, older people and age-friendly features are very visible in the cityscapes of both municipalities, and this is a positive expression of the changing demographics

An action for the (2,0) self-dual tensor multiplet in a conformal supergravity background

We present the action for a self-dual tensor in six dimensions, coupled to a (2,0) conformal supergravity background. This action gives rise to the expected equations of motion. An alternative look upon one of the gauge symmetries clarifies its role in the supersymmetry transformation rules and the realisation of the algebra.Comment: 14 pages, accepted by Class. Quant. Gra

Batalin-Vilkovisky gauge-fixing of a chiral two-form in six dimensions

We perform the gauge-fixing of the theory of a chiral two-form boson in six dimensions starting from the action given by Pasti, Sorokin and Tonin. We use the Batalin-Vilkovisky formalism, introducing antifields and writing down an extended action satisfying the classical master equation. Then we gauge-fix the three local symmetries of the extended action in two different ways.Comment: 15 pages, latex, no figures, version accepted by Class. Quant. Gra