Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 6 de 6
Filtrar
Más filtros










Base de datos
Intervalo de año de publicación
1.
Tidsskr Nor Laegeforen ; 140(10)2020 06 30.
Artículo en Inglés, Noruego | MEDLINE | ID: mdl-32602327

RESUMEN

BACKGROUND: Benzodiazepines are also used as intoxicants. This can be dangerous, particularly in multi-substance abuse. We describe cases of acute poisoning related to substance abuse of benzodiazepines in patients at the main A&E clinic in Oslo. MATERIAL AND METHOD: We included all patients treated for substance abuse poisoning with benzodiazepines and/or z-hypnotics at the Oslo Accident and Emergency Outpatient Clinic from 1 October 2013 to 30 September 2015. The patients were found through a retrospective review of the A&E clinic's registers. Data were taken from patient records. Diagnosis of the toxic agent was based on the attending doctor's recorded clinical evaluation. RESULTS: Of 1 037 cases, 787 (76 %) were men. The median age was 36 (interquartile range 28-46, range 14-78). Clonazepam (Rivotril) was the most frequently occurring drug, with 575 cases (55 %), followed by diazepam (Stesolid, Valium, Vival) 158 (15 %), alprazolam (Xanor) 125 (12 %) and oxazepam (Sobril) 94 (9 %). Zopiclone (Imovane, Zopitin) and zolpidem (Stilnoct) occurred rarely, in 25 (2 %) and 11 (1 %) cases, respectively. Benzodiazepines were combined with other intoxicants in 936 (90 %) cases, most frequently heroin 484 (47 %), ethanol 321 (31 %) and amphetamine 199 (19 %). INTERPRETATION: In substance abuse poisoning, benzodiazepines were very often combined with other intoxicants, most frequently opioids, ethanol and/or amphetamine.


Asunto(s)
Intoxicación , Trastornos Relacionados con Sustancias , Adulto , Analgésicos Opioides , Benzodiazepinas , Femenino , Humanos , Hipnóticos y Sedantes , Masculino , Estudios Retrospectivos , Trastornos Relacionados con Sustancias/epidemiología
2.
J Vis Exp ; (159)2020 05 22.
Artículo en Inglés | MEDLINE | ID: mdl-32510496

RESUMEN

The current particle size threshold of the European Particle Number (PN) emission standards is 23 nm. This threshold could change because future combustion engine vehicle technology may emit large amounts of sub-23 nm particles. The Horizon 2020 funded project DownToTen (DTT) developed a sampling and measurement method to characterize particle emissions in this currently unregulated size range. A PN measurement system was developed based on an extensive review of the literature and laboratory experiments testing a variety of PN measurement and sampling approaches. The measurement system developed is characterized by high particle penetration and versatility, which enables the assessment of primary particles, delayed primary particles, and secondary aerosols, starting from a few nanometers in diameter. This paper provides instruction on how to install and operate this Portable Emission Measurement System (PEMS) for Real Drive Emissions (RDE) measurements and assess particle number emissions below the current legislative limit of 23 nm.


Asunto(s)
Conducción de Automóvil , Monitoreo del Ambiente/métodos , Nanopartículas/análisis , Nanopartículas/química , Tamaño de la Partícula , Emisiones de Vehículos/análisis , Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/química , Monitoreo del Ambiente/instrumentación , Laboratorios , Material Particulado/análisis , Material Particulado/química
3.
Conserv Biol ; 33(1): 152-163, 2019 02.
Artículo en Inglés | MEDLINE | ID: mdl-29882221

RESUMEN

Loss of natural forests by forest clearcutting has been identified as a critical conservation challenge worldwide. This study addressed forest fragmentation and loss in the context of the establishment of a functional green infrastructure as a spatiotemporally connected landscape-scale network of habitats enhancing biodiversity, favorable conservation status, and ecosystem services. Through retrospective analysis of satellite images, we assessed a 50- to 60-year spatiotemporal clearcutting impact trajectory on natural and near-natural boreal forests across a sizable and representative region from the Gulf of Bothnia to the Scandinavian Mountain Range in northern Fennoscandia. This period broadly covers the whole forest clearcutting period; thus, our approach and results can be applied to comprehensive impact assessment of industrial forest management. The entire study region covers close to 46,000 km2 of forest-dominated landscape in a late phase of transition from a natural or near-natural to a land-use modified state. We found a substantial loss of intact forest, in particular of large, contiguous areas, a spatial polarization of remaining forest on regional scale where the inland has been more severely affected than the mountain and coastal zones, and a pronounced impact on interior forest core areas. Salient results were a decrease in area of the largest intact forest patch from 225,853 to 68,714 ha in the mountain zone and from 257,715 to 38,668 ha in the foothills zone, a decrease from 75% to 38% intact forest in the inland zones, a decrease in largest patch core area (assessed by considering 100-m patch edge disturbance) from 6114 to 351 ha in the coastal zone, and a geographic imbalance in protected forest with an evident predominance in the mountain zone. These results demonstrate profound disturbance of configuration of the natural forest landscape and disrupted connectivity, which challenges the establishment of functional green infrastructure. Our approach supports the identification of forests for expanded protection and conservation-oriented forest landscape restoration.


Asunto(s)
Ecosistema , Taiga , Biodiversidad , Conservación de los Recursos Naturales , Bosques , Estudios Retrospectivos
4.
PeerJ ; 4: e2049, 2016.
Artículo en Inglés | MEDLINE | ID: mdl-27231664

RESUMEN

Background. Foraging efficiency is critical in determining the success of organisms and may be affected by a range of factors, including resource distance and quality. For social insects such as ants, outcomes must be considered at the level of both the individual and the colony. It is important to understand whether anthropogenic disturbances, such as forestry, affect foraging loads, independent of effects on the quality and distribution of resources. We asked if ants harvest greater loads from more distant and higher quality resources, how individual efforts scale to the colony level, and whether worker loads are affected by stand age. Methods. First, we performed a fine-scale study examining the effect of distance and resource quality (tree diameter and species) on harvesting of honeydew by red wood ants, Formica aquilonia, in terms of crop load per worker ant and numbers of workers walking up and down each tree (ant activity) (study 1). Second, we modelled what the combination of load and worker number responses meant for colony-level foraging loads. Third, at a larger scale, we asked whether the relationship between worker load and resource quality and distance depended on stand age (study 2). Results. Study 1 revealed that seventy percent of ants descending trees carried honeydew, and the percentage of workers that were honeydew harvesters was not related to tree species or diameter, but increased weakly with distance. Distance positively affected load mass in both studies 1 and 2, while diameter had weak negative effects on load. Relationships between load and distance and diameter did not differ among stands of different ages. Our model showed that colony-level loads declined much more rapidly with distance for small diameter than large diameter trees. Discussion. We suggest that a negative relationship between diameter and honeydew load detected in study 1 might be a result of crowding on large diameter trees close to nests, while the increase in honeydew load with distance may result from resource depletion close to nests. At the colony level, our model suggests that very little honeydew was harvested from more distant trees if they were small, but that more distant larger trees continued to contribute substantially to colony harvest. Although forestry alters the activity and foraging success of red wood ants, study 2 showed that it does not alter the fundamental rules determining the allocation of foraging effort.

5.
Faraday Discuss ; 189: 439-54, 2016 Jul 18.
Artículo en Inglés | MEDLINE | ID: mdl-27089302

RESUMEN

Reducing ambient concentrations of nitrogen dioxide (NO2) remains a key challenge across many European urban areas, particularly close to roads. This challenge mostly relates to the lack of reduction in emissions of oxides of nitrogen (NOx) from diesel road vehicles relative to the reductions expected through increasingly stringent vehicle emissions legislation. However, a key component of near-road concentrations of NO2 derives from directly emitted (primary) NO2 from diesel vehicles. It is well-established that the proportion of NO2 (i.e. the NO2/NOx ratio) in vehicle exhaust has increased over the past decade as a result of vehicle after-treatment technologies that oxidise carbon monoxide and hydrocarbons and generate NO2 to aid the emissions control of diesel particulate. In this work we bring together an analysis of ambient NOx and NO2 measurements with comprehensive vehicle emission remote sensing data obtained in London to better understand recent trends in the NO2/NOx ratio from road vehicles. We show that there is evidence that NO2 concentrations have decreased since around 2010 despite less evidence of a reduction in total NOx. The decrease is shown to be driven by relatively large reductions in the amount of NO2 directly emitted by vehicles; from around 25 vol% in 2010 to 15 vol% in 2014 in inner London, for example. The analysis of NOx and NO2 vehicle emission remote sensing data shows that these reductions have been mostly driven by reduced NO2/NOx emission ratios from heavy duty vehicles and buses rather than light duty vehicles. However, there is also evidence from the analysis of Euro 4 and 5 diesel passenger cars that as vehicles age the NO2/NOx ratio decreases. For example the NO2/NOx ratio decreased from 29.5 ± 2.0% in Euro 5 diesel cars up to one year old to 22.7 ± 2.5% for four-year old vehicles. At some roadside locations the reductions in primary NO2 have had a large effect on reducing both the annual mean and number of hourly exceedances of the European Limit Values of NO2.

6.
PLoS One ; 10(3): e0118896, 2015.
Artículo en Inglés | MEDLINE | ID: mdl-25756871

RESUMEN

The increasing demand for biofuels from logging residues require serious attention on the importance of dead wood substrates on clear-cuts for the many forestry-intolerant saproxylic (wood-inhabiting) species. In particular, the emerging harvest of low stumps motivates further study of these substrates. On ten clear-cuts we compared the species richness, abundance and species composition of saproxylic beetles hatching from four to nine year old low stumps, high stumps and logs of Norway spruce. By using emergence traps we collected a total of 2,670 saproxylic beetles among 195 species during the summers of 2006, 2007 and 2009. We found that the species assemblages differed significantly between high stumps and logs all three years. The species assemblages of low stumps, on the other hand, were intermediate to those found in logs and high stumps. There were also significant difference in species richness between the three examined years, and we found significant effect of substrate type on richness of predators and fungivores. As shown in previous studies of low stumps on clear-cuts they can sustain large numbers of different saproxylic beetles, including red-listed species. Our study does, in addition to this fact, highlight a possible problem in creating just one type of substrate as a tool for conservation in forestry. Species assemblages in high stumps did not differ significantly from those found in low stumps. Instead logs, which constitute a scarcer substrate type on clear-cuts, provided habitat for a more distinct assemblage of saproxylic species than high stumps. It can therefore be questioned whether high stumps are an optimal tool for nature conservation in clear-cutting forestry. Our results also indicate that low stumps constitute an equally important substrate as high stumps and logs, and we therefore suggest that stump harvesting is done after carefully evaluating measures to provide habitat for saproxylic organisms.


Asunto(s)
Escarabajos/fisiología , Distribución Animal , Animales , Conservación de los Recursos Naturales , Ecosistema , Agricultura Forestal , Noruega , Estaciones del Año , Madera
SELECCIÓN DE REFERENCIAS
DETALLE DE LA BÚSQUEDA
...