Convergent changes in the maternal emission and pup reception of the rabbit mammary pheromone

Summary. Lactating rabbit females emit volatile odour cues that trigger specialized motor actions leading to sucking. But the activity of these cues may change with advancing lactation. Here, we tested this possibility in three experiments. In Exp. 1, we assessed whether 2-day-old pups respond differently to the odour of milk from females in early (day 2) as compared to late (day 23) lactation. In Exp. 2, a compound bearing pheromonal properties, the Mammary Pheromone (MP), was dosed in these milks to assess whether its concentration is correlated with behavioural activity. In Exp. 3, the responsiveness to a constant level of MP was compared in d2 versus d23-pups. Run on 240 pups, the assays showed that a) the milk activity declines between d2 and d23 of lactation; b) during this same period, the concentration of the MP decreases in milk; c) the MP itself becomes less active to elicit oral grasping in pre-weaning pups than in newborns. These results indicate that the MP is active during the period when pups are exclusively dependent on milk. The convergent changes in emission and reception of this pheromone may sequentially warrant that pups are first attracted to the mammae, and then that they progressively disinvest the mother as they begin to eat solid food and to be attracted by other conspecifics.     

An expanded conceptual framework for solution-focused management of chemical pollution in European waters

Background

This paper describes a conceptual framework for solutions-focused management of chemical contaminants built on novel and systematic approaches for identifying, quantifying and reducing risks of these substances.

Methods

The conceptual framework was developed in interaction with stakeholders representing relevant authorities and organisations responsible for managing environmental quality of water bodies. Stakeholder needs were compiled via a survey and dialogue. The content of the conceptual framework was thereafter developed with inputs from relevant scientific disciplines.

Results

The conceptual framework consists of four access points: Chemicals, Environment, Abatement and Society, representing different aspects and approaches to engaging in the issue of chemical contamination of surface waters. It widens the scope for assessment and management of chemicals in comparison to a traditional (mostly) perchemical risk assessment approaches by including abatement- and societal approaches as optional solutions. The solution-focused approach implies an identification of abatement- and policy options upfront in the risk assessment process. The conceptual framework was designed for use in current and future chemical pollution assessments for the aquatic environment, including the specific challenges encountered in prioritising individual chemicals and mixtures, and is applicable for the development of approaches for safe chemical management in a broader sense. The four access points of the conceptual framework are interlinked by four key topics representing the main scientific challenges that need to be addressed, i.e.: identifying and prioritising hazardous chemicals at different scales; selecting relevant and efficient abatement options; providing regulatory support for chemicals management; predicting and prioritising future chemical risks. The conceptual framework aligns current challenges in the safe production and use of chemicals. The current state of knowledge and implementation of these challenges is described.

Conclusions

The use of the conceptual framework, and addressing the challenges, is intended to support: (1) forwarding sustainable use of chemicals, (2) identification of pollutants of priority concern for cost-effective management, (3) the selection of optimal abatement options and (4) the development and use of optimised legal and policy instruments.

     

Assessment of multi-contaminant exposure in a cancer treatment center: a 2-year monitoring of molds,mycotoxins, endotoxins,and glucans in bioaerosols

Indoor air quality in health care facilities is a major public health concern, particularly for immunocompromised patients who may be exposed to microbiological contaminants such as molds, mycotoxins, endotoxins, and (1,3)-ß-D-glucans. Over 2 years, bioaerosols were collected on a monthly basis in a cancer treatment center (Centre F. Baclesse, Normandy, France), characterized from areas where there was no any particular air treatment. Results showed the complexity of mycoflora in bioaerosols with more than 100 fungal species identified. A list of major strains in hospital environments could be put forward due to the frequency, the concentration level, and/or the capacity to produce mycotoxins in vitro: Aspergillus fumigatus, Aspergillus melleus, Aspergillus niger, Aspergillus versicolor, Cladosporium herbarum, Purpureocillium lilacinum, and Penicillium brevicompactum. The mean levels of viable airborne fungal particles were less than 30.530 CFU per m³ of air and were correlated to the total number of 0.30 to 20 μm particles. Seasonal variations were observed with fungal particle peaks during the summer and autumn. Statistical analysis showed that airborne fungal particle levels depended on the relative humidity level which could be a useful indicator of fungal contamination. Finally, the exposure to airborne mycotoxins was very low (only 3 positive samples), and no mutagenic activity was found in bioaerosols. Nevertheless, some fungal strains such as Aspergillus versicolor or Penicillium brevicompactum showed toxigenic potential in vitro.     

Selection of plants for optimization of vegetative filter strips treating runoff from turfgrass

Runoff from turf environments, such as golf courses, is of increasing concern due to the associated chemical contamination of lakes, reservoirs, rivers, and ground water. Pesticide runoff due to fungicides, herbicides, and insecticides used to maintain golf courses in acceptable playing condition is a particular concern. One possible approach to mitigate such contamination is through the implementation of effective vegetative filter strips (VFS) on golf courses and other recreational turf environments. The objective of the current study was to screen ten aesthetically acceptable plant species for their ability to remove four commonly-used and degradable pesticides: chlorpyrifos (CP), chlorothalonil (CT), pendimethalin (PE), and propiconazole (PR) from soil in a greenhouse setting, thus providing invaluable information as to the species composition that would be most efficacious for use in VFS surrounding turf environments. Our results revealed that blue flag iris (Iris versicolor) (76% CP, 94% CT, 48% PE, and 33% PR were lost from soil after 3 mo of plant growth), eastern gama grass (Tripsacum dactyloides) (47% CP, 95% CT, 17% PE, and 22% PR were lost from soil after 3 mo of plant growth), and big blue stem (Andropogon gerardii) (52% CP, 91% CT, 19% PE, and 30% PR were lost from soil after 3 mo of plant growth) were excellent candidates for the optimization of VFS as buffer zones abutting turf environments. Blue flag iris was most effective at removing selected pesticides from soil and had the highest aesthetic value of the plants tested.     

Development of a site‐specific cleanup goal for PAHs in soil based on anthropogenic background levels

During removal of an industrial landfill in Folsom, California, fill material was excavated and processed through a mechanical screening plant to segregate soil from construction and demolition debris. The segregated soil was stockpiled and analyzed for a wide range of chemical groups to determine if the soil could be backfilled on‐site. The analytical results indicated many of the stockpiles had concentrations of polycyclic aromatic hydrocarbons (PAHs) that exceeded US EPA Regional Screening Levels, and a large quantity of soil was initially classified as requiring off‐site disposal at considerable cost. Because PAHs are ubiquitous in urban settings and the landfill did not contain a significant source of PAHs, development of a site‐specific PAH cleanup goal was proposed to regulators. Cal/EPA guidance for using on‐site data to develop a background threshold for metals was applied to the development of the PAH cleanup goal. The Cal/EPA approach involves demonstrating whether the data belong to a single population or multiple populations based on data distribution tests and probability plots. This article explains the statistical and graphical methods that were used to demonstrate that the Cal/EPA approach was valid for PAHs and that the calculated cleanup level was consistent with published anthropogenic background levels of PAHs in California and across the United States. The site‐specific PAH cleanup goal enabled most of the soil to be backfilled on‐site, saving about $227,000 in transportation and disposal costs, and regulators subsequently approved unrestricted future use of the property. © 2010 Wiley Periodicals, Inc.     

Environmental impacts of training activities at an air weapons range

Within Canada, it has been recognized in the last decade that military training activities may have impacts on the environmental quality of training ranges. However, impacts of activities specific to Air Force Bases have not yet been intensely documented. A hydrogeological study was accomplished at the Cold Lake Air Weapons Range, Alberta, to evaluate the environmental impacts of using bombs, rockets, strafing, and open burning/open detonation (OB/OD) on the quality of soil, ground water, surface water, and lake sediments. Samples were analyzed for metals, anions, ammonium perchlorate (NH(4)ClO(4)), and energetic materials (EM). It was found that training activities did not result in measured values being exceeded on the basis of guidance values for surface water and lake sediments. Contamination by metals was mostly limited to soils, and some metals may be related to the use of bombs (Cd, Cu, Pb), strafe (Cu), and rockets (As, Ba, Cd, Cr, Cu, Fe, Ni, Pb, U, V, Zn). TNT (2,4,6-trinitrotoluene) was the main EM found in soils, while RDX (hexahydro-1,3,5-trinitro-1,3,5-triazine) was more common in ground water. Both are related to live bombing, while nitroglycerine (NG) is related to rocket use and was detected in soils only. Aluminum, nitrate, and ammonium perchlorate detected in ground water may be related to live bombing or rockets. OB/OD operations resulted in the presence of various EM in soils, and of perchlorate and nitrate in ground water. Contamination by metals and explosives in soils was localized around the targets and varied significantly in time; however, in ground water it was more constant and may persist for a period of several years after a target has been removed.     

Fungal Degradation of Poly(Butylene Adipate-Co-Terephthalate) in Soil and in Compost

The present work mainly dedicated to fungal degradation of poly(butylene adipate-co-terephthalate) [PBAT], to enclose the role of fungi in a real process of biodegradation, the degree of degradation, and to understand the kinetics of PBAT biodegradation. Respirometer tests were realized in soil at 30 °C, and in compost at 30 and 58 °C. Results have shown that temperature is one of the essential parameters governing the fungal degradation of PBAT. Moreover, the final rates of PBAT biodegradation in an inoculated compost with fungi and in a real compost were found comparable, which means that the selected fungi were efficient as much as a mixture of bacteria and fungi. The curves of PBAT biodegradation were modeled by Hill sigmoid. Fungal degradation was completed by investigating the physical and the chemical properties of the polymer during the process of degradation using several analytical methods such as matrix assisted laser desorption ionization-time of fly spectroscopy, size exclusion chromatography, and differential scanning calorimetry. These experiments led to a better understanding of the various stages of fungal degradation of PBAT: hydrolysis as well as mineralization. Furthermore, the analysis of metabolizing products was investigated also.     

Views of the City: Multiple pathways to sustainable transport futures

In this paper we look behind the notion of sustainable transport and highlight the tensions and contradictions between the different ways of achieving this. The paper examines transportation plans for a major UK city and describes how these develop the idea and practice of sustainable transport and demand management along three quite distinct trajectories. By focusing on both the technological and the institutional dimensions of three different routes to sustainable transport, the analysis explicates the different ways in which the urban transport problem is framed, the different socio-technical logics of demand management embodied in the plans and the differing ways in which institutional relationships are (re)constituted. A key finding is that technological and institutional innovations are inversely related so that radical technological innovation often serves to reinforce existing social relations of power and exclusion. The conclusion drawn is that the choice is not just between a sustainable and an unsustainable transport future, but also between different forms of sustainability.     

Do herbicide treatments reduce the sensitivity of mosquito larvae to insecticides?

Invasive mosquitoes are economic and sanitary concerns especially in Europe and America. Most work has emphasized the role of resistance [Berrada, S., Fournier, D., Cuany, A., Nguyen, T.X., 1994. Identification of resistance mechanisms in a selected laboratory strain of Cacopsylla pyri (Homoptera: Psyllidae): altered acetylcholinesterases and detoxifying oxidases. Pesticide Biochemistry and Physiology 48, 41-47; Hemingway, J., Hawkes, N.J., McCarroll, L., Ranson, H., 2004. The molecular basis of insecticide resistance in mosquitoes. Insect Biochemistry and Molecular Biology 34, 653-665] to insecticides. Compounds acting on larval sensitivity to insecticides are not well studied and their action remains poorly understood. Among several residual chemicals in ecosystems, particularly in wetlands, we identified a possible interaction of an herbicide on larval resistance to an insecticide. Our work contributes to the global control of mosquito populations by identifying possible pathways of resistance to insecticides of these vectors. Resistance or tolerance to insecticide treatments might contribute to successful invasion by mosquitoes. Here we report an ecotoxicological approach to test the hypothesis of an indirect effect of atrazine on mortality of an invasive vector. A brief contact (48h) between Aedes aegypti mosquito larvae and atrazine led to a modification of larval sensitivity to an insecticide: using atrazine as an inducer led to a decrease in the mortality of larvae treated with Bacillus thuringiensis var. israelensis (Bti).     

A morphological investigation of soot produced by the detonation of munitions

The morphology of three different detonation soot samples along with other common soot materials such as carbon black, diesel soot and chimney soot was studied by elemental and proximate analysis, X-ray diffraction and electron microscopy. The goal of this study was to better define the morphology of the detonation soot in order to better assess the interactions of this type of soot with explosive residues. The detonation soot samples were obtained by the detonation of artillery 155mm projectiles filled with either pure TNT (2,4,6-trinitrotoluene) or composition B, a military explosive based on a mixture of TNT and RDX (trimethylentrinitramine). The carbon content of the soot samples varied considerably depending on the feedstock composition. Detonation soot contains less carbon and more nitrogen than the other carbonaceous samples studied, due to the molecular structure of the energetic materials detonated such as TNT and RDX. The ash concentration was higher for detonation soot samples due to the high metal content coming from the projectiles shell and to the soil contamination which occurred during the detonation. By X-ray diffraction, diamond and graphite were found to be the major crystalline carbon forms in the detonation soot. Two electron microscopy techniques were used in this study to visualise the primary particles and to try to explain the formation mechanism of detonation soot samples.