Chronic toxicity of fenoxycarb to the midge Chironomus riparius after exposure in sediments of different composition

Background, aim, and scope  

Fenoxycarb is an insect growth regulator widely used to control a variety of pests. As a juvenile hormone analogue, it interacts with the natural hormones involved in insect development, inhibiting metamorphosis to the adult stage. Adverse effects of fenoxycarb on non-target organisms have been repeatedly observed and its rapid dissipation from water to the organic fraction of the sediment is known. The aim of this work was to investigate the impact of fenoxycarb on the development of sediment-dwelling larvae of the midge Chironomus riparius after exposure to spiked sediment.     

Will breed-specific legislation reduce dog bites?

So how do we deal with biting dogs? To start with, we must remind ourselves that biting is a natural activity of all dogs, and that there is potential for injury. All dog owners must understand this and must be made aware that they are fully responsible for the actions of their dogs. I am not convinced that this is universally understood by dog owners, nor am I satisfied that every dog owner takes the necessary steps to train and socialize their dog. Owners need to be encouraged to actively work at inhibiting biting behaviour when dogs are young. As well, all dogs should be socialized to accept children, regardless of whether or not there are children living with the dog. Adults without dogs need to learn that dogs don''t understand "people''s rights," and that dogs should not be expected to act differently with different people. Adults also need to understand that young children should never be left alone with a dog (or a cat) without supervision, and that all children should be taught how to behave around dogs, particulary around dogs they don''t know. So long as we have dogs living with us there will be people who get bitten. The most effective way to prevent bites is to encourage dog owners to become knowledgeable about their animals and to train and socialize them so that they can become good dog neighbours. Many municipalities already have by-laws that deal with animal bites, and in Ontario the Dog Owners Liability Act has proven to be effective in confining, restraining or disposing of biting or attacking dogs judged to be a definite threat to public health and safety, and when evidence warrants, there is always Section #221 of the Criminal Code of Canada. Most legislation deals with bites after the fact. If we want to prevent all bites, there is only one sure way and that is to ban all dogs. That is of course as unrealistic as trying to prevent bites by enacting breed specific legislation.     

Element-selective single atom imaging

Electron energy-loss spectroscopy (EELS) is widely used to identify elemental compositions of materials studied by microscopy. We demonstrate that the sensitivity and spatial resolution of EELS can be extended to the single-atom limit. A chemical map for gadolinium (Gd) clearly reveals the distribution of Gd atoms inside a single chain of metallofullerene molecules (Gd@C82) generated within a single-wall carbon nanotube. This characterization technique thus provides the "eyes" to see and identify individual atoms in nanostructures. It is likely to find broad application in nanoscale science and technology research.     

BiKF AdaMus: a novel research project studying the response and adaptive potential of single species and communities to climate change in combination with other stressors

Introduction

How will the combination of climate-induced physical/chemical changes and anthropogenic pollution impact key species and biodiversity, and thus the ecosystem functions in future?

Discussion

The project AdaMus within the newly founded Biodiversity and Climate Research Centre BiK^F aims to understand the prospective ecosystem stress responses and adaptive potential of species and communities to multiple stressors to provide reliable predictions of future developments in terrestric, aquatic and marine environments.

Conclusion

Long-term experiments with terrestrial, aquatic and marine species and communities will be conducted under IPCC predicted climate conditions. In terrestric and limnic experiments, additional co-stressors such as pesticides and alien species are introduced to test for interactions. In the case of marine plankton, potential consequences of multiple climate-related changes in the physical environment (temperature, salinity and oxygen) will be analysed.     

Difference in Amounts and Composition of Dew from Different Types of Dew Collectors

Dew was collected using several kinds of collectors at the same time, and the composition was compared. The volumes per unit surface areas of dew formed were different based on the types of collectors. It is found that the amounts of the ions, which in part come from gaseous substances, such as organic acids, nitrous acid, etc., per unit area in dew increase with dew volume per unit surface area. On the other hand, chloride, nitrate, sodium, potassium and magnesium which come from only particles showed no variation with the dew volume per unit surface area. These results suggest that the composition of dew varied by the dew volume per unit surface area formed in the different collectors. Dew is usually collected on a polytetrafluoroethylene (PTFE) sheet. The above result suggests that the dew concentration on the PTFE sheet does not represent the real dew concentration on various materials, such as leaves, cars, roofs, road, etc. To determine the real concentration of dew on a material, the material itself has to be usedas a collector. The PTFE sheet could be used as a standard dew sampler forcomparison of dew formed at various places.     

Erratum

The oxidation of nitric oxide (NO) to nitrogen dioxide (NO₂), the initial step in formation of nitric acid, was analyzed based on atmospheric observations in urban central Osaka, Japan, focusing the relation with the behavior of photoreactive hydrocarbon (HC) species. Simultaneous observation at two vehicle exhaust monitoring stations, one has higher oxidation ratio of NO (NO₂/NOx) and the other has lower NO₂/NOx, in November 1998 and May 1999, had been held and investigated in current report. By using concentration ratios of reactive HCs to acetylene, obvious relation between NO₂/NOx and HCs reaction was implied. In November observations, decline of aromatics to acetylene ratios with increasing NO₂/NOx were observed at one station, while not appeared at the other station. Opposite tendencies were observed at the two sampling stations from November to May, implying complicated regional characteristics of photochemistries.     

Transport of Atmospheric Pollutants from East Asia

Air-borne measurements of air pollutants transported from northeast Asia to Japan and the Pacific Ocean were carried out three times from 1996 to 1999 over the seas between Japan and Asian Continent. Those campaigns were named PEACAMPOT II under auspices of the IGAC/APARE program. A transport pattern of a highly polluted air mass from central China was found. Such air mass was driven by the quick movement of low pressure traveling from Taiwan area to the northeast of Japan. This finding supported well the results of modeling studies for long-range transport of atmospheric pollutants from East Asia.