Studying foraging behavior to improve bait sprays application to control Drosophila suzukii.

BACKGROUND: Foraging behavior in insects is optimised for locating scattered resources in a complex environment. This behavior can be exploited for use in pest control. Inhibition of feeding can protect crops whereas stimulation can increase the uptake of insecticides. For example, the success of a bait spray, depends on either contact or ingestion, and thus on the insect finding it. METHODS: To develop an effective bait spray against the invasive pest, Drosophila suzukii, we investigated aspects of foraging behavior that influence the likelihood that the pest interacts with the baits, in summer and winter morphotypes. We video-recorded the flies' approach behavior towards four stimuli in a two-choice experiment on strawberry leaflets. To determine the most effective bait positioning, we also assessed where on plants the pest naturally forages, using a potted raspberry plant under natural environmental conditions. We also studied starvation resistance at 20 °C and 12 °C for both morphs. RESULTS: We found that summer morph flies spent similar time on all baits (agar, combi-protec, yeast) whereas winter morphs spent more time on yeast than the other baits. Both morphs showed a preference to feed at the top of our plant's canopy. Colder temperatures enhanced survival under starvation conditions in both morphs, and mortality was reduced by food treatment. CONCLUSIONS: These findings on feeding behavior support informed decisions on the type and placement of a bait to increase pest control.

The effect of eye movement desensitization and reprocessing (EMDR) on abdominal pain in patients with irritable bowel syndrome (IBS): a study protocol for a randomized controlled trial (EMDR4IBS).

BACKGROUND: Irritable bowel syndrome (IBS) is a highly prevalent disorder for which treatment options such as medication, diets, and hypnotherapy either have shown limited effect or relieve symptoms in only a limited subset of patients. Abdominal pain is the key criterion for the diagnosis and is deemed the most distressing IBS symptom, and the most disruptive of everyday life. A growing body of research demonstrates the effect of Eye Movement Desensitization and Reprocessing (EMDR) on chronic pain. EMDR is known as a safe and successful treatment for disorders in which unresolved traumatic memories play a role in the cause or maintenance of symptoms. In IBS, activated memories may increase pain through pain flashbacks and the stress generated by unresolved memories. The aim of this study is to ascertain whether applying EMDR to traumatic memories including pain memories will reduce abdominal pain in IBS patients. METHODS: This study is a randomized controlled trial which will be conducted at a city hospital in the Netherlands. Adult patients with considerable IBS pain (pain intensity at least 60/100 during at least 5/10 days) will be randomly assigned to either EMDR therapy or the wait list. We aim to include 34 participants. The EMDR condition comprises seven sessions, around 90 min in length delivered weekly, the first of which is a case conceptualization session. All participants will be assessed at baseline, post-treatment, and at 3 months follow-up. The primary outcome measure is pain intensity on a Likert scale which is self-reported daily during a 2-week period. Secondary outcomes include similar daily ratings on other IBS symptoms and reported hindrance of valued activities, and also standardized questionnaires on IBS symptoms and Quality of Life. Data will be analyzed by a Linear Mixed Effects Model for repeated measures. DISCUSSION: The results are expected to gain insight into the effectiveness of EMDR treatment on abdominal pain in IBS. As there are very few effective treatment options for IBS-related abdominal pain, this study could have important implications for clinical practice. TRIAL REGISTRATION: Human ethics committee MEC-U NL71740.100.20. International Clinical Trial Registry Platform: NL8894. Prospectively registered on 28 January 2020.

Polyploidy in animals: effects of gene expression on sex determination, evolution and ecology.

Polyploidy is rarer in animals than in plants. Why? Since Muller's observation in 1925, many hypotheses have been proposed and tested, but none were able to completely explain this intriguing fact. New genomic technologies enable the study of whole genomes to explain the constraints on or consequences of polyploidization, rather than focusing on specific genes or life history characteristics. Here, we review a selection of old and recent literature on polyploidy in animals, with emphasis on the consequences of polyploidization for gene expression patterns and genomic network interactions. We propose a conceptual model to contrast various scenarios for changes in genomic networks, which may serve as a framework to explain the different evolutionary dynamics of polyploidy in animals and plants. We also present new insights of genetic sex determination in animals and our emerging understanding of how animal sex determination systems may hamper or enable polyploidization, including some recent data on haplodiploids. We discuss the role of polyploidy in evolution and ecology, using a gene regulation perspective, and conclude with a synopsis regarding the effects of whole genome duplications on the balance of genomic networks. See also the sister articles focusing on plants by Ashman et al. and Madlung and Wendel in this themed issue.

Sex peptide of Drosophila melanogaster males is a global regulator of reproductive processes in females.

Seminal fluid proteins (Sfps) alter female behaviour and physiology and can mediate sexual conflict. In Drosophila melanogaster, a single Sfp, the sex peptide (SP), triggers remarkable post-mating responses in females, including altered fecundity, feeding, immunity and sexual receptivity. These effects can favour the evolutionary interests of males while generating costs in females. We tested the hypothesis that SP is an upstream master-regulator able to induce diverse phenotypes through efficient induction of widespread transcriptional changes in females. We profiled mRNA responses to SP in adult female abdomen (Abd) and head+thorax (HT) tissues using microarrays at 3 and 6 h following mating. SP elicited a rich, subtle signature of temporally and spatially controlled mRNAs. There were significant alterations to genes linked to egg development, early embryogenesis, immunity, nutrient sensing, behaviour and, unexpectedly, phototransduction. There was substantially more variation in the direction of differential expression across time points in the HT versus Abd. The results support the idea that SP is an important regulator of gene expression in females. The expression of many genes in one sex can therefore be under the influence of a regulator expressed in the other. This could influence the extent of sexual conflict both within and between loci.

Alcohol consumption and body weight change in postmenopausal women: results from the Women's Health Initiative.

OBJECTIVE: To determine whether alcohol consumption is associated with incident overweight or obesity in normal-weight, postmenopausal women. DESIGN: Prospective cohort study considering baseline alcohol consumption and subsequent weight change over 7 years. SUBJECTS: 15,920 normal-weight (body mass index (BMI): 18.5 to <25 kg m(-2)), postmenopausal women enrolled in the Women's Health Initiative Clinical Trial. MEASUREMENTS: Body weight change, and incident overweight and obesity (BMI, 25.0 to <30 and ≥ 30 kg m(-2)) over 7 years. RESULTS: One-third of the 13,822 women included in the analytical cohort reported no alcohol consumption. BMI differed little between abstainers (22.8±1.58 kg m(-2)) and alcohol consumers in the upper quintile (22.7±1.53 kg m(-2)). Among normal-weight women, the risk of becoming overweight or obese over a 7-year follow-up period was 35% or 88% lower, respectively, for women in the upper quintile of alcohol intake relative to abstainers (hazard ratio (HR), 0.65; 95% confidence interval (CI), 0.58-0.73; or HR, 0.12; 95% CI, 0.05-0.25, respectively). Risk for overweight and obesity was not significantly modified by age. Wine consumption showed the greatest protective association for risk of overweight (HR, 0.75; 95% CI, 0.68-0.84), followed by liquor (HR, 0.85; 95% CI, 0.78-0.93) and beer (HR, 0.90; 95% CI, 0.82-1.00). CONCLUSION: Postmenopausal women of normal weight who report moderate alcohol intake have a reduced risk of becoming overweight or obese over time. Perhaps, weight control measures in this population should target behaviors other than reduction in alcohol for those of normal BMI consuming moderate amounts.

Microbial strengthening of loose sand.

AIMS: To test whether the addition of Flavobacterium johnsoniae could increase the strength of saturated Ottawa 30 sand. METHODS AND RESULTS: A box model was built that simulates groundwater-like flow through a main sand compartment. Strength tests were performed at seven locations and at two depths, 10.8 and 20.3 cm below the top of the tank, using a vane shear device before and after the addition of bacteria. After the addition of Fl. johnsoniae, sand samples were obtained from multiple sampling ports on the vertical sides of the box model. The presence of a bacterial biofilm was confirmed by staining these sand samples with SYTO-9 and Alexa Fluor 633 and viewing with a confocal microscope. The average shear strength increases after the addition of Fl. johnsoniae were 15.2-87.5%, depending on the experimental conditions. CONCLUSIONS: Flavobacterium johnsoniae caused a statistically significant increase in the strength of saturated Ottawa 30 sand. SIGNIFICANCE AND IMPACT OF THE STUDY: Biofilm-forming bacteria can increase the shear strength of saturated sand. The addition of biofilm-forming bacteria to a building site may be an alternate method to mitigate the effects of liquefaction.

Molecular phylogeny of the salmonellae: relationships among Salmonella species and subspecies determined from four housekeeping genes and evidence of lateral gene transfer events.

The salmonellae are a diverse group of bacteria within the family Enterobacteriaceae that includes two species, Salmonella enterica and Salmonella bongori. In order to characterize the phylogenetic relationships of the species and subspecies of Salmonella, we analyzed four housekeeping genes, gapA, phoP, mdh and recA, comprising 3,459 bp of nucleotide sequence data for each isolate sequenced. Sixty-one isolates representing the most common serotypes of the seven subspecies of Salmonella enterica and six isolates of Salmonella bongori were included in this study. We present a robust phylogeny of the Salmonella species and subspecies that clearly defines the lineages comprising diphasic and monophasic subspecies. Evidence of intersubspecies lateral gene transfer of the housekeeping gene recA, which has not previously been reported, was obtained.

The mode of evolution of aggregation pheromones in Drosophila species.

Aggregation pheromones are used by fruit flies of the genus Drosophila to assemble on breeding substrates, where they feed, mate and oviposit communally. These pheromones consist of species-specific blends of chemicals. Here, using a phylogenetic framework, we examine how differences among species in these pheromone blends have evolved. Theoretical predictions, genetic evidence, and previous empirical analysis of bark beetle species, suggest that aggregation pheromones do not evolve gradually, but via major, saltational shifts in chemical composition. Using pheromone data for 28 species of Drosophila we show that, unlike with bark beetles, the distribution of chemical components among species is highly congruent with their phylogeny, with closely related species being more similar in their pheromone blends than are distantly related species. This pattern is also strong within the melanogaster species group, but less so within the virilis species group. Our analysis strongly suggests that the aggregation pheromones of Drosophila exhibit a gradual, not saltational, mode of evolution. We propose that these findings reflect the function of the pheromones in the ecology of Drosophila, which does not hinge on species specificity of aggregation pheromones as signals.