Behavioural modes in butterflies: their implications for movement and searching behaviour

Animals move in ‘modes’ where movement patterns relate to specific behaviours. Despite much work on the movement of butterflies, their behavioural modes are relatively unexplored. Here we analysed the behaviour of the model butterfly species the meadow brown, Maniola jurtina. We identified modes in both sexes and across habitats varying in resource density. We found that, in nectar-rich habitats, males had more diverse behaviour than females, engaging in a unique ‘high-flight’ mode associated with mate search, whereas females were primarily nectaring or inactive. In nectar-poor habitats, both sexes were similar, switching between flight and inactivity. We also identified the movement parameters of the modes, finding that, for both sexes, movements associated with nectaring were slower and more tortuous and, for males, the mode associated with mate searching was straighter and faster. Using an individual-based random-walk model, we investigated the effects of behaviour on movement predictions by comparing a mode-switching model with a version including intraspecific variation and another assuming homogeneity between individuals. For both sexes, including modes affected the mean and shape of the displacement rate compared to models assuming homogeneity, although for females modes increased displacement 1.5 times while for males they decreased it by a third. Both models also differed substantially from models assuming intraspecific variation. Finally, using a new model of search behaviour we investigated the general conditions under which individuals should engage in an exclusive search for host plants or receptive females. Parameterized for M. jurtina, the model predicted males should engage exclusively in mate search, but females only when searching is very efficient. The model provides a framework for analysing the searching behaviour of other butterfly species

Friedreich's Ataxia (GAA)n•(TTC)n Repeats Strongly Stimulate Mitotic Crossovers in Saccharomyces cerevisae

Expansions of trinucleotide GAA•TTC tracts are associated with the human disease Friedreich's ataxia, and long GAA•TTC tracts elevate genome instability in yeast. We show that tracts of (GAA)230•(TTC)230 stimulate mitotic crossovers in yeast about 10,000-fold relative to a “normal” DNA sequence; (GAA)n•(TTC)n tracts, however, do not significantly elevate meiotic recombination. Most of the mitotic crossovers are associated with a region of non-reciprocal transfer of information (gene conversion). The major class of recombination events stimulated by (GAA)n•(TTC)n tracts is a tract-associated double-strand break (DSB) that occurs in unreplicated chromosomes, likely in G1 of the cell cycle. These findings indicate that (GAA)n•(TTC)n tracts can be a potent source of loss of heterozygosity in yeast

Measuring the health-related Sustainable Development Goals in 188 countries : a baseline analysis from the Global Burden of Disease Study 2015

Background In September, 2015, the UN General Assembly established the Sustainable Development Goals (SDGs). The SDGs specify 17 universal goals, 169 targets, and 230 indicators leading up to 2030. We provide an analysis of 33 health-related SDG indicators based on the Global Burden of Diseases, Injuries, and Risk Factors Study 2015 (GBD 2015). Methods We applied statistical methods to systematically compiled data to estimate the performance of 33 health-related SDG indicators for 188 countries from 1990 to 2015. We rescaled each indicator on a scale from 0 (worst observed value between 1990 and 2015) to 100 (best observed). Indices representing all 33 health-related SDG indicators (health-related SDG index), health-related SDG indicators included in the Millennium Development Goals (MDG index), and health-related indicators not included in the MDGs (non-MDG index) were computed as the geometric mean of the rescaled indicators by SDG target. We used spline regressions to examine the relations between the Socio-demographic Index (SDI, a summary measure based on average income per person, educational attainment, and total fertility rate) and each of the health-related SDG indicators and indices. Findings In 2015, the median health-related SDG index was 59.3 (95% uncertainty interval 56.8-61.8) and varied widely by country, ranging from 85.5 (84.2-86.5) in Iceland to 20.4 (15.4-24.9) in Central African Republic. SDI was a good predictor of the health-related SDG index (r(2) = 0.88) and the MDG index (r(2) = 0.2), whereas the non-MDG index had a weaker relation with SDI (r(2) = 0.79). Between 2000 and 2015, the health-related SDG index improved by a median of 7.9 (IQR 5.0-10.4), and gains on the MDG index (a median change of 10.0 [6.7-13.1]) exceeded that of the non-MDG index (a median change of 5.5 [2.1-8.9]). Since 2000, pronounced progress occurred for indicators such as met need with modern contraception, under-5 mortality, and neonatal mortality, as well as the indicator for universal health coverage tracer interventions. Moderate improvements were found for indicators such as HIV and tuberculosis incidence, minimal changes for hepatitis B incidence took place, and childhood overweight considerably worsened. Interpretation GBD provides an independent, comparable avenue for monitoring progress towards the health-related SDGs. Our analysis not only highlights the importance of income, education, and fertility as drivers of health improvement but also emphasises that investments in these areas alone will not be sufficient. Although considerable progress on the health-related MDG indicators has been made, these gains will need to be sustained and, in many cases, accelerated to achieve the ambitious SDG targets. The minimal improvement in or worsening of health-related indicators beyond the MDGs highlight the need for additional resources to effectively address the expanded scope of the health-related SDGs.Peer reviewe

Biodiesel production via trans-esterification using Pseudomonas cepacia immobilized on cellulosic polyurethane

In this work, Pseudomonas cepacia lipase immobilized on cellulosic polyurethane was used as a catalyst for biodiesel production via trans-esterification reactions in order to provide cost-effective methods of enzyme recycling. The efficacy of the immobilized enzyme catalyst at low loading (6.2 wt %) and the effects of temperature, water content, and reaction time in model trans-esterification of glyceryl trioctanoate were investigated extensively. It was found that water was necessary for the reaction of glyceryl trioctanoate with ethanol to proceed. A high conversion of glyceryl trioctanoate (∼70%) was obtained at 35 °C, with only 5.0 wt % of water content over a reaction period of 12 h

Adsorption of phosphate by halloysite (7 angstrom) nanotubes (HNTs)

The adsorption and retention of phosphates in soil systems is of wide environmental importance, and understanding the surface chemistry of halloysite (a common soil clay mineral) is also of prime importance in many emerging technological applications of halloysite nanotubes (HNTs). The adsorption of phosphate anions on tubular halloysite (7 angstrom) has been studied to gain a greater understanding of the mechanism and kinetics of adsorption on the surface of HNTs. Two well-characterized tubular halloysites with differing morphologies have been studied: one polygonal prismatic and one cylindrical, where the cylindrical form has a greater surface area and shorter tube length. Greater phosphate adsorption of up to 42 mu mol g(-1) is observed on the cylindrical halloysite when compared to the polygonal prismatic sample, where adsorption reached a maximum of just 15 mu mol g(-1) compared to a value for platy kaolinite (KGa-2) of 8 mu mol g(-1). Phosphate adsorption shows strong pH dependence, and the differences in phosphate sorption between the prismatic and cylindrical morphologies suggest that phosphate absorption does not occur at the same pH-dependent alumina edge sites and that the lumen may have a greater influence on uptake for the cylindrical form

An Introduction to Pyrolysis and Catalytic Pyrolysis: Versatile Techniques for Biomass Conversion

A significant proportion of renewable feedstocks research has been devoted to the production of bio-fuels and bio-chemicals from biomass, primarily via thermochemical conversion processes. This chapter presents an overview of alternative pyrolysis methodologies, which can convert biomass directly into solid (char), liquid (bio-oil), and gaseous products. In this report, the influence of the pyrolysis conditions employed, the design of reactor, and the nature of the biomass feedstock used upon the chemical composition of the product fractions are surveyed. A summary of the mechanisms by which the pyrolysis of the principle biomass constituents occurs is given. This is accompanied by an indication of the complications that arise as a result of the complex and heterogeneous nature of biomass, including the potential roles of the various salts and minerals naturally present in such feeds. From a commercial standpoint, the multi-component nature, different forms and structures of biomass, all pose significant challenges for the utilization of biomass in the manufacture of fuels and chemicals. Consequently, the in and ex situ use of a host of additives and catalysts (including molecular sieves, metal oxides, and transition metal-modified oxides) is reviewed, which have been incorporated in order to provide selectivity in pyrolytic biomass upgrading

Selection for fitness at the individual or population levels: Modeling effects of genetic modifications in microalgae on productivity and environmental safety

International audienceA mechanistic model of microalgae is used to explore the implications of modifying microalgal chlorophyll content and photosynthetic efficiency with an aim to optimizing commercial biomass production. The models show the potential for a ten-fold increase in microalgae productivity in genetically modified versus unmodified configurations, while also enabling the use of bioreactors of greater optical depth operating at lower dilution rates. Analysis suggests that natural selection of a trait benefiting the individual (high Chl:C; i.e. high antennae size) conflicts with artificial selection of a trait (low Chl:C) of most benefit to production at the population level. The implication is that GM strains rather than strains selected from nature will be most beneficial for commercial algal biofuels production. Further, escaped GM algae populations may, depending on the specific nature of the modification, be quickly out-competed by the natural forms because individually a high Chl:C is beneficial in low light environments. However, it remains possible that changes in biochemical composition associated with genetic modification of photosystem competence, or with other selection processes to enhance commercial gain, may adversely affect the value of such organisms as prey for zooplankton, leading to the unwanted generation of future harmful algae

Changes in higher heating value and ash content of seaweed during ensiling

A problem in the use of macroalgae for biofuel is that harvesting of seaweed is generally seasonal, and there is a need to preserve and store seaweed to supply year-round production processes. Ensiling is a widely used preservation method in agriculture, but there is little research on ensiling seaweed. The changes in ash content, higher heating value (HHV) and dry matter (DM%) of algal biomass together with mass loss (ML) during ensilage for a year was studied for two species of seaweed, Laminaria digitata (LD) and Palmaria palmata (PP), with and without the addition of Lactobacillus plantarum. The mean ash content of the two species was significantly different (LD 24.3 % and PP 18.0 %) and remained constant after 90 days ensiling. The mean HHV before ensiling for PP was higher, 14.2 kJ g−1, compared to LD, 11.9 kJ g−1. Both the species (P < 0.05) and ensilage period (P < 0.05) had a significant effect on HHV. The overall DM% of the ensiled LD (22.4 %) and PP (22.0 %) were similar with a gradual increase in the DM% after 90 days ensiled. There was no effect of the ensiling with or without L. plantarum on DM%. There was a continuous wet matter loss during ensilage, and although the HHV of the ensiled wet biomass increased as the macroalgae became drier over time, the energy available from each kilogramme of wet macroalgae ensiled declined over the year to 78 % in LD and 59 % in PP