Intraspecific divergence between Grapholitha molesta (Tortricidae, Lepidoptera) populations from Italy and Greece in relation to temperature.

Genetic changes contributing to phenotypic and phenological differences within or between species have been identified for a handful of traits, but the relationship between alleles underlying intraspecific polymorphism and interspecific divergence is largely unknown. Particularly for economically important insects macroscopic diagnosis and assessment of species boundaries and related population dynamics is often problematic because of the limited morphological and/or biological traits. In this work we attempt to compare temperature driven physiological responses of Grapholita molesta populations from different areas along with an initial phylogenetic analysis. To evaluate region-specific moth phenology patterns, we used the data sets of flights during two successive growth seasons (2011 and 2012). Population sizes of G. molesta moth phenology depended strongly on the particular location of research and model performance that were applied to predict population dynamics was less effective in predicting the related data sets. In addition, several individual from two populations (Italy and Greece) were screened with two mtDNA loci (761 bp and 627 bp in length) revealing the levels of intraspecific divergence within this species between different geographic regions. Beside that, however, DNA barcoding revealed that at least two species other than G. molesta were also attracted by the G. molesta lures. It was thus made evident that DNA-based approaches can shed more light into variation in phenology observed among populations of the same species. With that, more work is on the way, including a comprehensive population study and a rigorous sampling of many more geographical regions to offer a more robust explanation of intraspecific divergence

Effects of valent image-based secondary tasks on verbal working memory

Two experiments examined if exposure to emotionally valent image-based secondary tasks introduced at different points of a free recall working memory (WM) task impair memory performance. Images from the International Affective Picture System (IAPS) varied in the degree of negative or positive valance (mild, moderate, strong) and were positioned at low, moderate and high WM load points with participants rating them based upon perceived valence. As predicted, and based on previous research and theory, the higher the degree of negative (Experiment 1) and positive (Experiment 2) valence and the higher the WM load when a secondary task was introduced, the greater the impairment to recall. Secondary task images with strong negative valance were more disruptive than negative images with lower valence at moderate and high WM load task points involving encoding and/or rehearsal of primary task words (Experiment 1). This was not the case for secondary tasks involving positive images (Experiment 2), although participant valence ratings for positive IAPS images classified as moderate and strong were in fact very similar. Implications are discussed in relation to research and theory on task interruption and attentional narrowing and literature concerning the effects of emotive stimuli on cognition

Development of a selective and sensitive sensor for urate determination based on tris(1,10-phenantroline)copper(II) bis(tetracyanoquinodimethanide) adsorbed on carbon nanotubes

The present work describes the development of a selective electrochemical sensor for urate based on tris(1,10-phenantroline) copper(II) bis(tetracyanoquinodimethanide) (Cu(phen)(3)(TCNQ)(2)) adsorbed on multi-walled carbon nanotubes (CNT). The composite material was characterized by infrared spectroscopy, scanning electron microscopy, and electrochemical impedance spectroscopy. The composite material showed an excellent electrocatalytic activity toward oxidation of urate. The heterogeneous charge transfer rate constant (k') between the analyte and the sensor was determined using linear sweep voltammetry experiments. The composite material shows a linear range from 5 up to 2500 mu mol L-1 with limit of detection of 1.05 mu mol L-1 and limit of quantification of 3.50 mu mol L-1. The high sensitivity and selectivity of the sensor for urate was sufficient for its determinationThe present work describes the development of a selective electrochemical sensor for urate based on tris(1,10-phenantroline)copper(II) bis(tetracyanoquinodimethanide) (Cu(phen)3(TCNQ)2) adsorbed on multi-walled carbon nanotubes (CNT). The composite materi261020352045FAPESP - FUNDAÇÃO DE AMPARO À PESQUISA DO ESTADO DE SÃO PAULOCNPQ - CONSELHO NACIONAL DE DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICOFAPEMA - FUNDAÇÃO DE AMPARO A PESQUISA E AO DESENVOLVIMENTO CIENTÍFICO E TECNOLÓGICO DO MARANHÃOsem informaçãosem informaçãosem informaçãoThe authors are grateful to Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq), INCTBio, Rede Mineira de Química, and Fundação de Amparo à Pesquisa do Estado do Maranhão (FAPEMA

Use of polyethylene glycol coatings for optical fibre humidity sensing

Humidity induced change in the refractive index and thickness of the polyethylene glycol (PEG) coatings are in situ investigated for a range from 10 to 95%, using an optical waveguide spectroscopic technique. It is experimentally demonstrated that, upon humidity change, the optical and swelling characteristics of the PEG coatings can be employed to build a plastic fibre optic humidity sensor. The sensing mechanism is based on the humidity induced change in the refractive index of the PEG film, which is directly coated onto a polished segment of a plastic optical fibre with dip-coating method. It is observed that PEG, which is a highly hydrophilic material, shows no monotonic linear response to humidity but gives different characteristics for various ranges of humidity levels both in index of refraction and in thickness. It undergoes a physical phase change from a semi-crystal line structure to a gel one at around 80% relative humidity. At this phase change point, a drastic decrease occurs in the index of refraction as well as a drastic increase in the swelling of the PEG film. In addition, PEG coatings are hydrogenated in a vacuum chamber. It is observed that the hydrogen has a preventing effect on the humidity induced phase change in PEG coatings. Finally, the possibility of using PEG coatings in construction of a real plastic fibre optic humidity sensor is discussed. (C) 2008 The Optical Society of Japan

Dual-task costs while walking increase in old age for some, but not for other tasks: an experimental study of healthy young and elderly persons

<p>Abstract</p> <p>Background</p> <p>It has been suggested in the past that the ability to walk while concurrently engaging in a second task deteriorates in old age, and that this deficit is related to the high incidence of falls in the elderly. However, previous studies provided inconsistent findings about the existence of such an age-related dual-task deficit (ARD). In an effort to explain this inconsistency, we explored whether ARD while walking emerges for some, but not for other types of task.</p> <p>Methods</p> <p>Healthy young and elderly subjects were tested under five different combinations of a walking and a non-walking task. The results were analysed jointly with those of a previous study from our lab, such that a total of 13 task combinations were evaluated. For each task combination and subject, we calculated the mean dual-task costs across both constituent tasks, and quantified ARD as the difference between those costs in elderly and in young subjects.</p> <p>Results</p> <p>An analysis of covariance yielded no significant effects of obstacle presence and overall task difficulty on ARD, but a highly significant effect of visual demand: non-walking tasks which required ongoing visual observation led to ARD of more than 8%, while those without such requirements led to near-zero ARD. We therefore concluded that the visual demand of the non-walking task is critical for the emergence of ARD while walking.</p> <p>Conclusion</p> <p>Combinations of walking and concurrent visual observation, which are common in everyday life, may contribute towards disturbed gait and falls during daily activities in old age. Prevention and rehabilitation programs for seniors should therefore include training of such combinations.</p

Quantifying the effects of temperature on mosquito and parasite traits that determine the transmission potential of human malaria

Malaria transmission is known to be strongly impacted by temperature. The current understanding of how temperature affects mosquito and parasite life history traits derives from a limited number of empirical studies. These studies, some dating back to the early part of last century, are often poorly controlled, have limited replication, explore a narrow range of temperatures, and use a mixture of parasite and mosquito species. Here, we use a single pairing of the Asian mosquito vector, An. stephensi and the human malaria parasite, P. falciparum to conduct a comprehensive evaluation of the thermal performance curves of a range of mosquito and parasite traits relevant to transmission. We show that biting rate, adult mortality rate, parasite development rate, and vector competence are temperature sensitive. Importantly, we find qualitative and quantitative differences to the assumed temperature-dependent relationships. To explore the overall implications of temperature for transmission, we first use a standard model of relative vectorial capacity. This approach suggests a temperature optimum for transmission of 29°C, with minimum and maximum temperatures of 12°C and 38°C, respectively. However, the robustness of the vectorial capacity approach is challenged by the fact that the empirical data violate several of the model's simplifying assumptions. Accordingly, we present an alternative model of relative force of infection that better captures the observed biology of the vector-parasite interaction. This model suggests a temperature optimum for transmission of 26°C, with a minimum and maximum of 17°C and 35°C, respectively. The differences between the models lead to potentially divergent predictions for the potential impacts of current and future climate change on malaria transmission. The study provides a framework for more detailed, system-specific studies that are essential to develop an improved understanding on the effects of temperature on malaria transmission

Pheromones and Other Semiochemicals for Monitoring Rare and Endangered Species

As global biodiversity declines, biodiversity and conservation have become ever more important research topics. Research in chemical ecology for conservation purposes has not adapted to address this need. During the last 10-15 years, only a few insect pheromones have been developed for biodiversity and conservation studies, including the identification and application of pheromones specifically for population monitoring. These investigations, supplemented with our knowledge from decades of studying pest insects, demonstrate that monitoring with pheromones and other semiochemicals can be applied widely for conservation of rare and threatened insects. Here, I summarize ongoing conservation research, and outline potential applications of chemical ecology and pheromone-based monitoring to studies of insect biodiversity and conservation research. Such applications include monitoring of insect population dynamics and distribution changes, including delineation of current ranges, the tracking of range expansions and contractions, and determination of their underlying causes. Sensitive and selective monitoring systems can further elucidate the importance of insect dispersal and landscape movements for conservation. Pheromone-based monitoring of indicator species will also be useful in identifying biodiversity hotspots, and in characterizing general changes in biodiversity in response to landscape, climatic, or other environmental changes