50 Years of Image Analysis

The Analysis of Time Series: An Introduction, 4th edn. By C. Chatfield. ISBN 0 412 31820 2. Chapman and Hall, London, 1989. 242 pp. £13.50.

The Analysis of Time Series: An Introduction

A positive temperature coefficient is the term which has been used to indicate that an increase in solubility occurs as the temperature is raised, whereas a negative coefficient indicates a decrease in solubility with rise in temperature.

Effect of Temperature

The mammalian brain exhibits diverse types of neural plasticity, including activity-dependent neurogenesis in the adult hippocampus. How transient activation of mature neurons leads to long-lasting modulation of adult neurogenesis is unknown. Here we identify Gadd45b as a neural activity-induced immediate early gene in mature hippocampal neurons. Mice with Gadd45b deletion exhibit specific deficits in neural activity-induced proliferation of neural progenitors and dendritic growth of newborn neurons in the adult hippocampus. Mechanistically, Gadd45b is required for activity-induced DNA demethylation of specific promoters and expression of corresponding genes critical for adult neurogenesis, including brain-derived neurotrophic factor and fibroblast growth factor. Thus, Gadd45b links neuronal circuit activity to epigenetic DNA modification and expression of secreted factors in mature neurons for extrinsic modulation of neurogenesis in the adult brain.

/pdf/neuronal-activity-induced-gadd45b-promotes-epigenetic-dna-58akuopwzq.pdf

Neuronal Activity–Induced Gadd45b Promotes Epigenetic DNA Demethylation and Adult Neurogenesis

Theory predicts, and recent empirical studies have shown, that the diversity of plant species determines the diversity of associated herbivores and mediates ecosystem processes, such as aboveground net primary productivity (ANPP). However, an often-overlooked component of plant diversity, namely population genotypic diversity, may also have wide-ranging effects on community structure and ecosystem processes. We showed experimentally that increasing population genotypic diversity in a dominant old-field plant species, Solidago altissima, determined arthropod diversity and community structure and increased ANPP. The effects of genotypic diversity on arthropod diversity and ANPP were comparable to the effects of plant species diversity measured in other studies.

Supporting Online Material for Plant Genotypic Diversity Predicts Community Structure and Governs an Ecosystem Process

The familiar buzz of flying mosquitoes is an important mating signal, with the fundamental frequency of the female's flight tone signaling her presence. In the yellow fever and dengue vector Aedes aegypti, both sexes interact acoustically by shifting their flight tones to match, resulting in a courtship duet. Matching is made not at the fundamental frequency of 400 hertz (female) or 600 hertz (male) but at a shared harmonic of 1200 hertz, which exceeds the previously known upper limit of hearing in mosquitoes. Physiological recordings from Johnston's organ (the mosquito's "ear") reveal sensitivity up to 2000 hertz, consistent with our observed courtship behavior. These findings revise widely accepted limits of acoustic behavior in mosquitoes.

https://courses.cit.cornell.edu/bionb4240/Readings/Cator_etal2009.pdf

Harmonic convergence in the love songs of the dengue vector mosquito

Harmonic Convergence in the Love Songs of the

http://www.thethomaslab.net/uploads/Das2012.pdf

Malaria in India: The Center for the Study of Complex Malaria in India

Previous studies have suggested that Plasmodium parasites can manipulate mosquito feeding behaviours such as probing, persistence and engorgement rate in order to enhance transmission success. Here, we broaden analysis of this 'manipulation phenotype' to consider proximate foraging behaviours, including responsiveness to host odours and host location. Using Anopheles stephensi and Plasmodium yoelii as a model system, we demonstrate that mosquitoes with early stage infections (i.e. non-infectious oocysts) exhibit reduced attraction to a human host, whereas those with late-stage infections (i.e. infectious sporozoites) exhibit increased attraction. These stage-specific changes in behaviour were paralleled by changes in the responsiveness of mosquito odourant receptors, providing a possible neurophysiological mechanism for the responses. However, we also found that both the behavioural and neurophysiological changes could be generated by immune challenge with heat-killed Escherichia coli and were thus not tied explicitly to the presence of malaria parasites. Our results support the hypothesis that the feeding behaviour of female mosquitoes is altered by Plasmodium, but question the extent to which this is owing to active manipulation by malaria parasites of host behaviour.

https://royalsocietypublishing.org/doi/pdf/10.1098/rspb.2013.0711

‘Manipulation’ without the parasite: altered feeding behaviour of mosquitoes is not dependent on infection with malaria parasites

http://www.thethomaslab.net/uploads/Cator2012.pdf

Lauren J. Cator

Papers

Harmonic convergence in the love songs of the dengue vector mosquito

Harmonic Convergence in the Love Songs of the

Malaria in India: The Center for the Study of Complex Malaria in India

‘Manipulation’ without the parasite: altered feeding behaviour of mosquitoes is not dependent on infection with malaria parasites

Do malaria parasites manipulate mosquitoes