Effect of the trichothecene deoxynivalenol on brain biogenic monoamines concentrations in rats and chickens

Male Sprague-Dawley rats (180 g) and 28-day-old Single Comb White Leghorn Cockerels (300 g) were orally dosed with deoxynivalenol (DON) at 2.5 mg kg-1 body weight. In the first experiment, whole brains were collected at 2, 6, 12, 24 and 48 hours after the toxin treatment and analyzed for brain biogenic monoamines by high-performance liquid chromatography with electrochemical detection. Although several interesting trends were observed, DON did not influence whole brain concentrations of monoamine neurotransmitters or their metabolites in either species, at any time. In a second experiment, brains were collected 24 hours postdosing, dissected into 5 brain regions (pons and medulla oblongata, cerebellum, hypothalamus, hippocampus and cerebral cortex), and analyzed. DON treatment resulted in significantly elevated concentrations of serotonin (HT) and 5-hydroxyindole-3-acetic acid (HIAA) in all brain regions of the rat. However, this was not seen in poultry, where DON treatment resulted in a decrease in norepinephrine (NE) in the hypothalamus and hippocampus, and a decrease in dopamine (DA) in the pons and medulla oblongata region. These results suggest that DON influences brain biogenic amine metabolism, and that there may be intraspecies differences in the central effects of this mycotoxin.     

A legal assessment of private land conservation in South America

Privately protected areas (PPAs) are a potentially innovative conservation tool. Legal recognition is necessary for their success, especially where there are institutional challenges to nature conservation, such as in South America. Although PPAs have increased in South America since the early 2000s, there is a critical information gap pertaining to their legal frameworks. We analyzed the level of landowner commitment to and governmental support for PPAs across countries in South America that officially recognize PPAs. We analyzed the legal framework governing PPAs and reviewed literature on them. This process was done in English and Spanish. The information we gathered was validated by 16 conservation experts from 10 South American countries. Because Peru is 1 of only 2 South American countries where local communities create and manage PPAs, we studied Peruvian PPAs in more detail by examining official creation documents and interviewing 13 local conservation professionals. We found inadequate minimum duration of PPAs and vague guidelines for conducting economic activities within them and a lack of governmental support (e.g., financial and technical support) for PPAs. Support was limited to the exemption from rural property taxes, which are relatively low compared with countries outside South America. In Peru, PPAs run by individuals and communities needed different legal frameworks because they were created with different objectives and had different sizes and duration of commitments. The prompt improvement of legal frameworks across South America is necessary for PPAs to achieve their aim of being places for enduring nature conservation in the region.     

Impact of osmolytes on buoyancy of marine phytoplankton

Marine phytoplanktonic cells can achieve neutral buoyancy only if the excess density of their relatively heavy structural materials (proteins, carbohydrates, silicate) is compensated for by the incorporation of materials that have densities less than seawater. We have calculated densities and osmotic concentrations for several marine algae, based on published values of structural materials and concentrations of inorganic ions and other osmolytes. The calculations, incorporating the partial molal volume, molecular mass, concentrations and osmotic coefficients, indicate that most published listings of intracellular osmolytes in marine algae are insufficient to provide the turgor known to exist. Similarly, the density of phytoplanktonic cells, calculated on the basis of known or estimated concentrations of cellular components, generally exceeds the density of seawater, which would cause negative buoyancy (sinking) throughout. We use models of osmotic concentration and cellular density in which we supplement known concentrations of osmolytes with proxy osmolytes. In particular, concentrations of some 100 mol m^-3 of quaternary ammonium derivatives can explain the deficits of both osmotic concentration and buoyancy.     

The relationship between emotional maturity and drinking-and-driving involvement among young adults

The relationship between emotional maturity and drinking-and-driving involvement among young adults aged 25–34 was investigated. The variables were sex, age broken down into two groups (25–29 and 30–39), and six drinking-and-driving categories. The Revised Huffman Inventory was used to measure emotional immaturity. The inventory was administered to graduate students enrolled at The University of Tennessee at Knoxville during the summer of 1981. A table of random numbers was used to obtain a sample of 326 subjects. A three-factor analysis of variance was used to test the hypotheses. If a difference among groups was significant (p< .05), Duncan's Multiple Range Test was applied to determine where those differences were. The conclusions were: (1) among females and males in the same age group, females are more emotionally mature than males; (2) age is a factor in emotional maturity in that emotional maturity increases with age; and (3) there appears to be a link between emotional maturity and drinking-and-driving involvement in that persons with lower emotional maturity are more likely to drive while under the influence of alcohol.     

Use of Linkage Disequilibrium Data to Estimate Effective Size of Hatchery and Natural Fish Populations

A primary parameter in the assessment of the viability of a population is its effective population size ( Ne ). Allozyme analysis of four groups of fishes provided data on linkage disequilibrium, which were then used to estimate Ne . The groups included hatchery samples of juvenile white seabass, Atractoscion nobilis , juvenile rainbow trout, Oncorhynchus mykiss , from the Shasta Hatchery, and juvenile chinook salmon, O. tshawytscha , from the Coleman National Fish Hatchery. The fourth sample consisted of juvenile chinook salmon from the threatened winter run in the upper Sacramento River. The groups of fish were chosen to represent different applications of the methodology to conservation of fishes. For a variety of reasons. Ne may be considerably lower than census counts of fish present in the parental populations. The Ne of the hatchery broodstock that produced the sample of juvenile white seabass was estimated to be approximately 10, although 25 adult white seabass were present in a mass spawning tank. Ne estimates for the parental populations of the Shasta and Coleman Hatchery samples were 35.8 and 132.5, respectively. The actual number of fish spawned at the Shasta Hatchery was approximately 40, whereas nearly 10,000 salmon were spawned at the Coleman Hatchery. The threatened winter run of chinook salmon had an estimated Ne of 85.5 and an approximate run size of 2000 salmon. The method of estimating effective population size from linkage disequilibrium data appears to result in realistic estimates of effective population size when adequate sample size and a sufficient number of polymorphic loci are available.     

Using expert elicitation to define successful adaptation to climate change

This paper develops definitions of adaptation and successful adaptation to climate change, with a view to evaluating adaptations. There is little consensus on the definition of adapting to climate change in existing debates or on the criteria by which adaptation actions can be deemed successful or sustainable. In this paper, a variant of the Delphi technique is used to elicit expert opinion on a definition of successful adaptation to climate change. Through an iterative process, expert respondents coalesced around a definition based on risk and vulnerability and agreed that a transparent and acceptable definition should reflect impacts on sustainability. According to the final definition, agreed by the Delphi panel, successful adaptation is any adjustment that reduces the risks associated with climate change, or vulnerability to climate change impacts, to a predetermined level, without compromising economic, social, and environmental sustainability.     

Automated Calibration of the METRIC‐Landsat Evapotranspiration Process

A remaining challenge to applying satellite‐based energy‐balance algorithms for operational estimation of evapotranspiration (ET) is the calibration of the energy‐balance model. Customized calibration for each image date is generally required to overcome biases associated with radiometric accuracy of the image, uncertainties in aerodynamic features of the landscape, background thermal conditions, and model assumptions. The CIMEC process (calibration using inverse modeling at extreme conditions) is an endpoint calibration procedure where near extreme conditions in the image are identified where the ET can be estimated and assigned. In the Mapping EvapoTranspiration at high Resolution with Internalized Calibration (METRIC?) energy‐balance model, two endpoints represent the dry and wet ends of the ET spectrum. Generally, user‐intervention is required to select locations in the image to produce best accuracy. To bring the METRIC and similar processes into the domain of less experienced operators, a consistent, reproducible, and dependable statistics‐based procedure is introduced where relationships between vegetation amount and surface temperature are used to identify a subpopulation of locations (pixels) in an image that may best represent the calibration endpoints. This article describes the background and logic for the statistical approach, how the statistics were developed, area of interest requirements and assumptions, adjustment for dry conditions in desert climates, and implementation in a common image processing environment (ERDAS Imagine).     

Linking chemical elements in forest floor humus (Oh-horizon) in the Czech Republic to contamination sources

While terrestrial moss and other plants are frequently used for environmental mapping and monitoring projects, data on the regional geochemistry of humus are scarce. Humus, however, has a much larger life span than any plant material. It can be seen as the “environmental memory” of an area for at least the last 60-100 years. Here concentrations of 39 elements determined by ICP-MS and ICP AES, pH and ash content are presented for 259 samples of forest floor humus collected at an average sample density of 1 site/300 km² in the Czech Republic. The scale of anomalies linked to known contamination sources (e.g., lignite mining and burning, metallurgical industry, coal fired power plants, metal smelters) is documented and discussed versus natural processes influencing humus quality. Most maps indicate a local impact from individual contamination sources: often more detailed sampling than used here would be needed to differentiate between likely sources.     

Rapid cultural adaptation can facilitate the evolution of large-scale cooperation

Over the past several decades, we have argued that cultural evolution can facilitate the evolution of large-scale cooperation because it often leads to more rapid adaptation than genetic evolution, and, when multiple stable equilibria exist, rapid adaptation leads to variation among groups. Recently, Lehmann, Feldman, and colleagues have published several papers questioning this argument. They analyze models showing that cultural evolution can actually reduce the range of conditions under which cooperation can evolve and interpret these models as indicating that we were wrong to conclude that culture facilitated the evolution of human cooperation. In the main, their models assume that rates of cultural adaption are not strong enough compared to migration to maintain persistent variation among groups when payoffs create multiple stable equilibria. We show that Lehmann et al. reach different conclusions because they have made different assumptions. We argue that the assumptions that underlie our models are more consistent with the empirical data on large-scale cultural variation in humans than those of Lehmann et al., and thus, our models provide a more plausible account of the cultural evolution of human cooperation in large groups.