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It has long been established that mature forests are mosaics of patches in different development phases but it has seldom explicitly been taken into account in ecological studies. We demonstrate here that these development phases, which are related to the population dynamics of trees, play an important role in the distribution of fauna based on observations on frugivorous birds. In an area close to the Calakmul Biosphere Reserve in Mexico, we studied the abundance of large forest bird species in relation to forest development phases, with a methodology that seems promising for ecological diagnosis and prognosis in forest management planning. Fine-scale forest mapping and bird counts were carried out in two block-transects of 40 m x 3000 m. Tree sampling in a sub-transect was used to generate population characteristics of trees, Large bird species preferred mature or senescent forest patches, whereas relatively young, growing forest patches were avoided. Important large tree species such as Manilkara zapota, Thouinia paucidentata, Guaiacum sanctum and Esenbeckia pentaphylla, characteristic of older forest patches, showed skewed size distributions indicating stress or overexploitation. The population of M. zapota, a key fruiting species that accounted for 26.5% of the total woody biomass, was most heavily affected by stress. A future collapse in the population of M. zapota, a decrease of the total area of older forest, and a decline in the abundance of large birds is likely if stress on the system continues at this level. (C) 2008 Elsevier B.V. All rights reserved.

A sudden and sharp rise in the C-14 content of the atmosphere, which occurred between ca. 850 and 760 calendar yr BC (ca. 2750-2450 BP on the radiocarbon time-scale), was contemporaneous with an abrupt climate change. In northwest Europe (as indicated by palaeoecological and geological evidence) climate changed from relatively warm and continental to oceanic. As a consequence, the ground-water table rose considerably in certain low-lying areas in The Netherlands. Archaeological and palaeoecological evidence for the abandonment of such areas in the northern Netherlands is interpreted as the effect of a rise of the water table and the extension of fens and bogs. Contraction of population and finally migration from these low-lying areas, which had become marginal for occupation, and the earliest colonisation by farming communities of the newly emerged salt marshes in the northern Netherlands around 2550 BP, is interpreted as the consequence of loss of cultivated land. Thermic contraction of ocean water and/or decreased velocity and pressure on the coast by the Gulf Stream may have caused a fall in relative sea-level rise and the emergence of these salt marshes. Evidence for a synchronous climatic change elsewhere in Europe and on other continents around 2650 BP is presented. Temporary aridity in tropical regions and a reduced transport of warmth to the temperate climate regions by atmospheric and/or oceanic circulation systems could explain the observed changes. As yet there is no clear explanation for this climate change and the contemporaneous increase of C-14 in the atmosphere. The strategy of C-14 wiggle-match dating can play an important role in the precise dating of organic deposits, and can be used to establish possible relationships between changing C-14 production in the atmosphere, climate change, and the impact of such changes on hydrology, vegetation, and human communities.

A good process understanding is the foundation for process optimization, process monitoring, end-point detection, and estimation of the end-product quality. Performing good process measurements and the construction of process models will contribute to a better process understanding. To improve the process knowledge it is common to build process models. These models are often based on first principles such as kinetic rates or mass balances. These types of models are also known as hard or white models. White models are characterized by being generally applicable but often having only a reasonable fit to real process data. Other commonly used types of models are empirical or black-box models such as regression and neural nets. Black-box models are characterized by having a good data fit but they lack a chemically meaningful model interpretation. Alternative models are grey models, which are combinations of white models and black models. The aim of a grey model is to combine the advantages of both black-box models and white models. In a qualitative case study of monitoring industrial batches using near-infrared (NIR) spectroscopy, it is shown that grey models are a good tool for detecting batch-to-batch variations and an excellent tool for process diagnosis compared to common spectroscopic monitoring tools.

It has been suggested that the relationship between income and the associated environmental pressure in terms of derived materials inputs and pollution levels may take an inverted-U shape, indicating a 'delinking' of environmental pressure from economic growth in relation to rising per capita incomes. The likelihood of such a relationship being persistent is discussed in the context of a simple macro model of industrial metabolism, and the possibility of 'relinking' clearly emerges. Data on specific indicators of environmental pressure (i.e., the throughput of materials, energy and the volume of transport) in 19 countries have been used to investigate patterns of delinking. The results suggest that delinking may not be persistent; already some advanced economies may be entering a new period of relinking. The relationships between environmental pressure and welfare in the medium long term may be N-shaped rather than inverted-U-shaped.

AbstractBackground: Chlorhexidine (CHX) 0.2% solution is still “the leading oral antiseptic” for controlling gingivitis. Side effects, however, limit the acceptability to users and the long‐term employment of a 0.2% CHX antiseptic in preventive dentistry. This stimulated the development of new formulations. The aim of the present study was to assess the effect on plaque inhibition and taste perception of two commercially available mouthrinses (0.12% CHX non‐alcohol base with 0.05% cetyl pyridinium chloride (Cpc) versus 0.2% CHX alcohol base).Methods: The study was designed as a single‐blind, randomized two group parallel experiment, to compare two different commercially available mouthrinses, during a 3‐day plaque accumulation model. Forty healthy volunteers were enrolled in the study and received a thorough dental prophylaxis at the beginning of the test period. Over a 72‐h experimental non‐brushing period, during which subjects abstained from all forms of mechanical oral hygiene, one group (test) used a 15 ml alcohol free 0.12% CHX (=18 mg) mouthrinse on a Cpc base (Perioaid®, CHX⊕Cpc), twice daily for 30 s. The other group (control) used a 10 ml 0.2% CHX (=20 mg) mouthrinse on an 11.8% ethanol alcohol base (Corsodyl®, CHX⊕Alc), twice daily for 60 s. After 72 h of plaque formation, the amount of plaque was evaluated. By the use of visual analogue scale, the subjects were asked for their appreciation of the taste of the mouthrinse they had used.Results: The mean plaque index for the CHX⊕Cpc group was 0.97 and for the CHX⊕Alc group 0.78. After 72 h of non‐brushing, there was no significant difference in plaque accumulation between the two groups. The answers to the questions (taste perception and after‐taste) showed a statistically significant difference between the two groups. The mean visual analogue scale (VAS) scores for taste appreciation on a scale from very bad to very good taste (0–10) were 5.92 for the CHX⊕Cpc group and 4.10 for the CHX⊕Alc group (p=0.02). The mean visual analogue scale (VAS) scores for the after‐taste on a scale from very short to very long (0–10) were 7.24 for the CHX⊕Cpc group and 5.38 for the CHX⊕Alc group.Conclusions: Within the limitations of the present study design, it can be concluded that rinsing with a 0.12% CHX mouthrinse on a non‐alcohol base with 0.05% Cpc (Perio‐Aid®) is not significantly different from rinsing with a 0.2% CHX mouthrinse on an alcohol base (Corsodyl®). It appears that the subjects appreciated the taste of the non‐alcohol CHX solution better but the after‐taste of the rinse remained longer in the mouth.

Abstract Public attitudes anywhere in Europe show moderate to strong support for the implementation of renewable energy. Nevertheless, planning wind power developments appears to be a complicated matter in most countries. The problems that have to be dealt with during decision making processes on the siting of wind turbines are usually referred to as mere ‘communication problems’. However, public attitudes towards wind power are fundamentally different from attitudes towards wind farms. This ‘gap’ causes misunderstandings about the nature of public support for renewables. In particular where planners easily assume support for renewables can be generated by information campaigns emphasising the environmental benefits, whereas opposition to renewable energy schemes can be explained by a selfish ‘not in my backyard’ attitude. Both explanations used by planners, authorities and, unfortunately, by many scholars, are falsified. Furthermore, policies that still take this ‘common knowledge’ for granted can have negative consequences for the implementation rates of renewables. Visual evaluation of the impact of wind power on landscape values is by far the dominant factor in explaining why some are opposed to wind power and others are supporting it. Moreover, feelings about equity and fairness appear the determinants of ‘backyard’ motives, instead of selfishness.