614 research outputs found
Milieurisicogrenzen voor ethylbenzeen and tributylfosfaat in water : Een voorstel voor waterkwaliteitsnormen volgens de Kaderrichtlijn Water
Het RIVM heeft in opdracht van het ministerie van Infrastructuur en Milieu (I&M) milieurisicogrenzen voor ethylbenzeen en tributylfosfaat in water bepaald. De stoffen zijn opgenomen in de Regeling monitoring Kaderrichtlijn Water, waarin staat aan welke eisen oppervlaktewater in Nederland moet voldoen. Voor deze stoffen moeten nieuwe waterkwaliteitsnormen worden vastgesteld, omdat de huidige normen niet zijn afgeleid volgens de meest recente methodiek. Op basis van meetgegevens over 2010 is er geen aanwijzing dat de voorgestelde waterkwaliteitsnormen worden overschreden. Normvoorstellen: De normvoorstellen voor ethylbenzeen zijn gebaseerd op de Europese risicobeoordeling voor deze stof. De KRW kent voor zoet en zout oppervlaktewater twee typen normen, de Jaargemiddelde Milieukwaliteitsnorm (JG-MKN) en de Maximaal Aanvaardbare Concentratie (MAC-MKN). De JG-MKN is de concentratie in water waarbij geen schadelijke effecten te verwachten zijn, gebaseerd op jaargemiddelde concentraties. Hiervoor zijn drie routes onderzocht: directe effecten op waterorganismen, indirecte effecten op vogels en zoogdieren via het eten van prooidieren en indirecte effecten op mensen via het eten van voedsel. De laagste van deze drie bepaalt de voorgestelde JG-MKN; voor ethylbenzeen is dat 65 microgram per liter voor zoetwater en 10 microgram per liter voor zoutwater. De Maximaal Aanvaardbare Concentratie (MAC-MKN) is de concentratie die het ecosysteem beschermt tegen kortdurende effecten. De voorgestelde MAC-MKN is 220 en 22 microgram per liter voor respectievelijk zoet- en zoutwater. Voor tributylfosfaat zijn al eerder voorstellen gedaan om de JG-MKN te herzien (66 en 6,6 microgram per liter voor zoet- en zoutwater). In aanvulling daarop wordt nu een MAC-MKN voorgesteld van 170 microgram per liter voor zoetwater en 17 microgram per liter voor zoutwater.RIVM has derived environmental risk limits (ERLs) for ethylbenzene and tributylphosphate in water. Both compounds are included in the Dutch decree on water quality objectives in the context of the Water Framework Directive (WFD). The standards have to be updated according to the current WFD-methodology. The values in this report serve as a scientific background for the Dutch Steering Committee for Substances, which is responsible for setting those standards. Monitoring data from 2010 indicate that the proposed standards will not be exceeded. Proposed standards: The proposal for ethylbenzene is based on the European risk assessment report (EU-RAR) for this compound. According to the WFD, two different standards are proposed for fresh- and saltwater. The Maximum Permissible Concentration (MPC) is the level at which no harmful effects are expected, based on annual average concentrations. This MPC is derived for three routes: direct ecotoxicity, secondary poisoning, and consumption of fish by humans. The lowest of these values determines the final MPC (65 microgram per litre for freshwater and 10 microgram per litre for saltwater). The Maximum Acceptable Concentration (MACeco) is the concentration which protects ecosystems from effects of short term concentration peaks. MAC-values of 220 and 22 microgram per litre are proposed for freshwater and saltwater, respectively. For tributylphosphate, updated MPC-values have been derived previously (66 and 6.6 microgram per litre for fresh- and saltwater). In addition, MAC-values of 170 and 17 microgram per litre are proposed for the respective water types.Ministerie van Infrastructuur en Milie
Children and older adults exhibit distinct sub-optimal cost-benefit functions when preparing to move their eyes and hands
"© 2015 Gonzalez et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited"Numerous activities require an individual to respond quickly to the correct stimulus. The provision of advance information allows response priming but heightened responses can cause errors (responding too early or reacting to the wrong stimulus). Thus, a balance is required between the online cognitive mechanisms (inhibitory and anticipatory) used to prepare and execute a motor response at the appropriate time. We investigated the use of advance information in 71 participants across four different age groups: (i) children, (ii) young adults, (iii) middle-aged adults, and (iv) older adults. We implemented 'cued' and 'non-cued' conditions to assess age-related changes in saccadic and touch responses to targets in three movement conditions: (a) Eyes only; (b) Hands only; (c) Eyes and Hand. Children made less saccade errors compared to young adults, but they also exhibited longer response times in cued versus non-cued conditions. In contrast, older adults showed faster responses in cued conditions but exhibited more errors. The results indicate that young adults (18 -25 years) achieve an optimal balance between anticipation and execution. In contrast, children show benefits (few errors) and costs (slow responses) of good inhibition when preparing a motor response based on advance information; whilst older adults show the benefits and costs associated with a prospective response strategy (i.e., good anticipation)
Positive and negative well-being and objectively measured sedentary behaviour in older adults: evidence from three cohorts
Background:
Sedentary behaviour is related to poorer health independently of time spent in moderate to vigorous physical activity. The aim of this study was to investigate whether wellbeing or symptoms of anxiety or depression predict sedentary behaviour in older adults.
Method:
Participants were drawn from the Lothian Birth Cohort 1936 (LBC1936) (n = 271), and the West of Scotland Twenty-07 1950s (n = 309) and 1930s (n = 118) cohorts. Sedentary outcomes, sedentary time, and number of sit-to-stand transitions, were measured with a three-dimensional accelerometer (activPAL activity monitor) worn for 7 days. In the Twenty-07 cohorts, symptoms of anxiety and depression were assessed in 2008 and sedentary outcomes were assessed ~ 8 years later in 2015 and 2016. In the LBC1936 cohort, wellbeing and symptoms of anxiety and depression were assessed concurrently with sedentary behaviour in 2015 and 2016. We tested for an association between wellbeing, anxiety or depression and the sedentary outcomes using multivariate regression analysis.
Results:
We observed no association between wellbeing or symptoms of anxiety and the sedentary outcomes. Symptoms of depression were positively associated with sedentary time in the LBC1936 and Twenty-07 1950s cohort, and negatively associated with number of sit-to-stand transitions in the LBC1936. Meta-analytic estimates of the association between depressive symptoms and sedentary time or number of sit-to-stand transitions, adjusted for age, sex, BMI, long-standing illness, and education, were β = 0.11 (95% CI = 0.03, 0.18) and β = − 0.11 (95% CI = − 0.19, −0.03) respectively.
Conclusion:
Our findings indicate that depressive symptoms are positively associated with sedentary behavior. Future studies should investigate the causal direction of this association
Increased risk of pneumonia in residents living near poultry farms: does the upper respiratory tract microbiota play a role?
BACKGROUND: Air pollution has been shown to increase the susceptibility to community-acquired pneumonia (CAP). Previously, we observed an increased incidence of CAP in adults living within 1 km from poultry farms, potentially related to particulate matter and endotoxin emissions. We aim to confirm the increased risk of CAP near poultry farms by refined spatial analyses, and we hypothesize that the oropharyngeal microbiota composition in CAP patients may be associated with residential proximity to poultry farms. METHODS: A spatial kernel model was used to analyze the association between proximity to poultry farms and CAP diagnosis, obtained from electronic medical records of 92,548 GP patients. The oropharyngeal microbiota composition was determined in 126 hospitalized CAP patients using 16S-rRNA-based sequencing, and analyzed in relation to residential proximity to poultry farms. RESULTS: Kernel analysis confirmed a significantly increased risk of CAP when living near poultry farms, suggesting an excess risk up to 1.15 km, followed by a sharp decline. Overall, the oropharyngeal microbiota composition differed borderline significantly between patients living <1 km and ≥1 km from poultry farms (PERMANOVA p = 0.075). Results suggested a higher abundance of Streptococcus pneumoniae (mean relative abundance 34.9% vs. 22.5%, p = 0.058) in patients living near poultry farms, which was verified by unsupervised clustering analysis, showing overrepresentation of a S. pneumoniae cluster near poultry farms (p = 0.049). CONCLUSION: Living near poultry farms is associated with an 11% increased risk of CAP, possibly resulting from changes in the upper respiratory tract microbiota composition in susceptible individuals. The abundance of S. pneumoniae near farms needs to be replicated in larger, independent studies
Exploring the Feasibility of Service Integration in a Low-Income Setting: A Mixed Methods Investigation into Different Models of Reproductive Health and HIV Care in Swaziland.
Integrating reproductive health (RH) with HIV care is a policy priority in high HIV prevalence settings, despite doubts surrounding its feasibility and varying evidence of effects on health outcomes. The process and outcomes of integrated RH-HIV care were investigated in Swaziland, through a comparative case study of four service models, ranging from fully integrated to fully stand-alone HIV services, selected purposively within one town. A client exit survey (n=602) measured integrated care received and unmet family planning (FP) needs. Descriptive statistics were used to assess the degree of integration per clinic and client demand for services. Logistic regression modelling was used to test the hypothesis that clients at more integrated sites had lower unmet FP needs than clients in a stand-alone site. Qualitative methods included in-depth interviews with clients and providers to explore contextual factors influencing the feasibility of integrated RH-HIV care delivery; data were analysed thematically, combining deductive and inductive approaches. Results demonstrated that clinic models were not as integrated in practice as had been claimed. Fragmentation of HIV care was common. Services accessed per provider were no higher at the more integrated clinics compared to stand-alone models (p>0.05), despite reported demand. While women at more integrated sites received more FP and pregnancy counselling than stand-alone models, they received condoms (a method of choice) less often, and there was no statistical evidence of difference in unmet FP needs by model of care. Multiple contextual factors influenced integration practices, including provider de-skilling within sub-specialist roles; norms of task-oriented routinised HIV care; perceptions of heavy client loads; imbalanced client-provider interactions hindering articulation of RH needs; and provider motivation challenges. Thus, despite institutional support, factors related to the social context of care inhibited provision of fully integrated RH-HIV services in these clinics. Programmes should move beyond simplistic training and equipment provision if integrated care interventions are to be sustained
The use of the multivariate Principal Response Curve (PRC) for community analysis: a case study on the effects of carbendazim on enchytraeids in Terrestrial Model Ecosystems (TME).
The effects of the fungicide carbendazim (formulation Derosal®) on enchytraeids were determined in Terrestrial Model Ecosystem (TME) tests. TMEs consisted of intact soil columns (diameter 17.5 cm; length 40 cm) taken from three grassland sites (Amsterdam (The Netherlands), Bangor (Wales, England) and Flörsheim (Germany)) or an arable site (Coimbra (Portugal)). Results for each TME site were evaluated using the multivariate Principal Response Curve (PRC) method. The resulting No-Observable Effect Concentrations (NOECs) for the community were compared with the NOECs generated by univariate statistical methods. Furthermore, the E
Waterkwaliteitsnormen voor PFOA : Een voorstel volgens de methodiek van de Kaderrichtlijn Water
RIVM proposes water quality standards for PFOA. This perfluoro compound has been used for the production of teflon and is found in many surface waters around the world. The quality standard for chronic exposure accounts for the accumulation of PFOA in fish. Using this information, RIVM calculated a safe concentration in water of 48 nanograms per liter, which is protective for lifetime consumption of fish by humans and wildlife. For this research an extensive overview was made of the scientific data on effects of PFOA on aquatic organisms and the accumulation in biota. Based on the oral risk limit for humans as derived recently by RIVM, a maximum allowable concentration in fish was calculated assuming a lifetime daily consumption. This biota standard is converted to an equivalent safe concentration in water using information on the uptake of PFOA from water by fish. Data on bioaccumulation are needed because the water quality standard for ecological effects on aquatic organisms is not sufficiently protective for food chain effects. PFOA has a relatively low toxicity for water organisms, but may pose a problem when entering the food chain via fish. The use of PFOA is restricted by European law, but it can still reach the environment from PFOA-containing products that were produced in the past. Because of its high persistence, emissions will lead to long term presence in the environment. An initial comparison with monitoring data indicates that the safe concentration derived in this research is not exceeded in Dutch surface waters.Het RIVM doet een voorstel voor waterkwaliteitsnormen voor PFOA. Deze perfluorverbinding is jarenlang gebruikt bij de productie van teflon en wordt overal ter wereld in het oppervlaktewater aangetroffen. De norm voor de langetermijn-blootstelling houdt rekening met de mate waarin PFOA zich ophoopt in vis. Met die informatie heeft het RIVM berekend dat een concentratie van 48 nanogram per liter veilig is als mensen, vogels en zoogdieren hun leven lang vis uit dat water zouden eten. Voor dit onderzoek is een uitgebreid overzicht gemaakt van wat er in de wetenschappelijke literatuur bekend is over de effecten van PFOA op waterorganismen en in welke mate ze deze stof opnemen. In eerder onderzoek heeft het RIVM bepaald hoeveel een mens van de stof zou mogen binnenkrijgen zonder daar schadelijke gevolgen van te ondervinden. Vervolgens is berekend wat er maximaal in vis zou mogen zitten als mensen elke dag gedurende hun hele leven vis zouden eten. Deze waarde in vis is vertaald naar een veilige concentratie in water. Dit is gedaan met behulp van gegevens over de mate waarin vissen PFOA opnemen vanuit het water. Deze werkwijze is gevolgd omdat de voedselketen onvoldoende wordt beschermd door de ecologische norm voor waterorganismen. PFOA is relatief weinig giftig voor waterorganismen zelf, maar kan een probleem vormen als de stof via vis in de voedselketen terechtkomt. Het gebruik van PFOA is in Europa inmiddels aan banden gelegd, maar kan nog wel vrijkomen uit producten waarin de stof in het verleden is verwerkt. Omdat PFOA nauwelijks afbreekt, zullen restanten nog lang in het milieu aanwezig blijven. Uit een eerste vergelijking met meetgegevens blijkt echter dat de veilige concentratie momenteel niet wordt overschreden in Nederlands oppervlaktewaterMinisterie van I&
Density responses of lesser-studied carnivores to habitat and management strategies in southern Tanzania's Ruaha-Rungwa landscape.
Compared to emblematic large carnivores, most species of the order Carnivora receive little conservation attention despite increasing anthropogenic pressure and poor understanding of their status across much of their range. We employed systematic camera trapping and spatially explicit capture-recapture modelling to estimate variation in population density of serval, striped hyaena and aardwolf across the mixed-use Ruaha-Rungwa landscape in southern Tanzania. We selected three sites representative of different habitat types, management strategies, and levels of anthropogenic pressure: Ruaha National Park’s core tourist area, dominated by Acacia-Commiphora bushlands and thickets; the Park’s miombo woodland; and the neighbouring community-run MBOMIPA Wildlife Management Area, also covered in Acacia-Commiphora. The Park’s miombo woodlands supported a higher serval density (5.56 [Standard Error = ±2.45] individuals per 100 km2) than either the core tourist area (3.45 [±1.04] individuals per 100 km2) or the Wildlife Management Area (2.08 [±0.74] individuals per 100 km2). Taken together, precipitation, the abundance of apex predators, and the level of anthropogenic pressure likely drive such variation. Striped hyaena were detected only in the Wildlife Management Area and at low density (1.36 [±0.50] individuals per 100 km2), potentially due to the location of the surveyed sites at the edge of the species’ global range, high densities of sympatric competitors, and anthropogenic edge effects. Finally, aardwolf were captured in both the Park’s core tourist area and the Wildlife Management Area, with a higher density in the Wildlife Management Area (13.25 [±2.48] versus 9.19 [±1.66] individuals per 100 km2), possibly as a result of lower intraguild predation and late fire outbreaks in the area surveyed. By shedding light on three understudied African carnivore species, this study highlights the importance of miombo woodland conservation and community-managed conservation, as well as the value of by-catch camera trap data to improve ecological knowledge of lesser-studied carnivores
The perceptions of social responsibility for community resilience to flooding: the impact of past experience, age, gender and ethnicity
Community resilience to flooding depends, to a large extent, on the participation of community members to take more responsibility for enhancing their own resilience. The perception of social responsibility (SR) which is argued to be one of the antecedents influencing individual’s willingness to undertake resilient behaviours can significantly contribute to community resilience through individual and collective actions. Understanding of factors influencing the perceptions of SR of individuals within community might help with developing strategies to increase the perceptions of SR. This research explores perceptions of SR in relation to flooding for householders and local businesses and establishes their relationships with experience of flooding and demographic factors of age, gender and ethnicity. The data were obtained via a questionnaire survey of three communities in Birmingham and one community in South East London, UK, three with experience of flooding and one without. A total of 414 responses were received and used in the multiple regression analysis. The analysis identified ‘experience of flooding’, ‘age’ and ‘South Asian’ ethnic group as significant variables, suggesting that older individuals from South Asian ethnic groups with previous experience of flooding are likely to be more socially responsible than others without these attributes
Nutraceutical therapies for atherosclerosis
Atherosclerosis is a chronic inflammatory disease affecting large and medium arteries and is considered to be a major underlying cause of cardiovascular disease (CVD). Although the development of pharmacotherapies to treat CVD has contributed to a decline in cardiac mortality in the past few decades, CVD is estimated to be the cause of one-third of deaths globally. Nutraceuticals are natural nutritional compounds that are beneficial for the prevention or treatment of disease and, therefore, are a possible therapeutic avenue for the treatment of atherosclerosis. The purpose of this Review is to highlight potential nutraceuticals for use as antiatherogenic therapies with evidence from in vitro and in vivo studies. Furthermore, the current evidence from observational and randomized clinical studies into the role of nutraceuticals in preventing atherosclerosis in humans will also be discussed
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