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Abstract Bactrocera tryoni (Froggatt) and Bactrocera neohumeralis (Hardy) are sibling fruit fly species that are sympatric over much of their ranges. Premating isolation of these close relatives is thought to be maintained in part by allochrony—mating activity in B. tryoni peaks at dusk, whereas in B. neohumeralis, it peaks earlier in the day. To ascertain whether differences in pheromone composition may also contribute to premating isolation between them, this study used solid-phase microextraction and gas chromatography-mass spectrometry to characterize the rectal gland volatiles of a recently collected and a more domesticated strain of each species. These glands are typical production sites and reservoirs of pheromones in bactrocerans. A total of 120 peaks were detected and 50 were identified. Differences were found in the composition of the rectal gland emissions between the sexes, species, and recently collected versus domesticated strains of each species. The compositional variation included several presence/absence and many quantitative differences. Species and strain differences in males included several relatively small alcohols, esters, and aliphatic amides. Species and strain differences in females also included some of the amides but additionally involved many fatty acid esters and 3 spiroacetals. While the strain differences indicate there is also heritable variation in rectal gland emissions within each species, the species differences imply that compositional differences in pheromones emitted from rectal glands could contribute to the premating isolation between B. tryoni and B. neohumeralis. The changes during domestication could also have significant implications for the efficacy of Sterile Insect Technique control programs.

Previously, we assessed the pathogenicity of eleven endemic entomopathogenic fungi (EPF), including six Beauveria isolates, four Metarhizium isolates, and one M. pingshaense, against the agricultural pest Spodoptera frugiperda (fall armyworm, FAW). We found that four Beauveria and one Metarhizium isolates were effective, with Beauveria isolates B-0571 and B-1311 exhibiting high mortality within 24 h post-spore application. This study aimed to identify and characterise the entomopathogenesis mechanisms of these isolates as potential FAW biocontrol agents. All Beauveria isolates were determined as B. bassiana, the Metarhizium isolates as two M. robertsii, one M. majus, and an unknown Metarhizium species. Despite the high mortality from B-0571 and B-1311 isolates, scanning electron microscopy showed no fungal spore germination on dead larvae 24 h after spore application. Four insecticide compound gene clusters, i.e., bassianolide, beauvericin, beauveriolide, and oosporein, were identified and characterised in all B. bassiana isolates. These compounds are hypothesised to contribute to the high early mortality rates in FAWs. Identifying and characterising gene clusters encoding these insecticide compounds in B-0571 and B-1311 will contribute to a better understanding of the entomopathogenicity of these isolates that will be vital to developing these EPF isolates as sustainable alternative FAW biocontrol agents.

The development of effective pest management strategies for Spodoptera frugiperda is a high priority for crop protection across its invasive ranges. Here, we examined six Beauveria and five Metarhizium fungal isolates against this pest. Two Beauveria isolates (B-0571, B-1311) induced high mortality toward 3rd and 6th instar caterpillars and adults. For B-0571 mortality was 82.81 ± 5.75%, 61.46 ± 6.83%, and 93.75 ± 3.61%, and 73.72 ± 2.51%, 71.88 ± 5.41%, and 97.92 ± 2.08% for B-1311, with deaths in caterpillars largely occurring under 24 h (3rd instar control 0.74 ± 0.33%, B-0571 73.96 ± 7.85% and B-1311 62.08 ± 3.67%; 6th instar control 0%, B-0571 66.67% ± 11.02% and B-1311 62.5% ± 9.55%). Infection from both Beauveria isolates fully prevented reproduction in surviving S. frugiperda females. In contrast, all five Metarhizium isolates tested and the remaining four Beauveria isolates exhibited lower virulence. The discovery of two highly virulent Beauveria fungal isolates to S. frugiperda opens avenues to develop novel biological control tools against this highly invasive pest.

Abstract Allochrony can be an important premating isolating mechanism in insects but its physiological basis has seldom been determined. It operates at a diurnal scale to differentiate mating times of some closely related tephritid taxa. For example, the sympatric sibling species Bactrocera tryoni (Froggatt) and Bactrocera neohumeralis (Hardy) mate at dusk and during the day, respectively. Rectal gland emissions of courting males function as sex pheromones in B. tryoni and recent evidence shows differences between the 2 species in many volatiles released from crushed rectal glands. Here we use gas chromatography–mass spectrometry to show that the head space compositions of whole male emissions of each species are generally but not invariably correlated with those of their respective rectal glands and they also differ between the species. Further, while the compositions of the whole male emissions do not vary diurnally in either species, the total amounts of the emissions do, in species-specific ways, with those of B. tryoni higher at dusk and night and those of B. neohumeralis higher during the day. Thus, the species differ substantially in their diurnal patterns of total whole fly emissions in a manner consistent with their allochrony, while the compositions of the emissions also differ substantially, which could also contribute to their premating isolation but is independent of their allochrony.

Background The presence of population structure in a sample may confound the search for important genetic loci associated with disease. Our four samples in the Family Investigation of Nephropathy and Diabetes (FIND), European Americans, Mexican Americans, African Americans, and American Indians are part of a genome- wide association study in which population structure might be particularly important. We therefore decided to study in detail one component of this, individual genetic ancestry (IGA). From SNPs present on the Affymetrix 6.0 Human SNP array, we identified 3 sets of ancestry informative markers (AIMs), each maximized for the information in one the three contrasts among ancestral populations: Europeans (HAPMAP, CEU), Africans (HAPMAP, YRI and LWK), and Native Americans (full heritage Pima Indians). We estimate IGA and present an algorithm for their standard errors, compare IGA to principal components, emphasize the importance of balancing information in the ancestry informative markers (AIMs), and test the association of IGA with diabetic nephropathy in the combined sample. Results A fixed parental allele maximum likelihood algorithm was applied to the FIND to estimate IGA in four samples: 869 American Indians; 1385 African Americans; 1451 Mexican Americans; and 826 European Americans. When the information in the AIMs is unbalanced, the estimates are incorrect with large error. Individual genetic admixture is highly correlated with principle components for capturing population structure. It takes ~700 SNPs to reduce the average standard error of individual admixture below 0.01. When the samples are combined, the resulting population structure creates associations between IGA and diabetic nephropathy. Conclusions The identified set of AIMs, which include American Indian parental allele frequencies, may be particularly useful for estimating genetic admixture in populations from the Americas. Failure to balance information in maximum likelihood, poly-ancestry models creates biased estimates of individual admixture with large error. This also occurs when estimating IGA using the Bayesian clustering method as implemented in the program STRUCTURE. Odds ratios for the associations of IGA with disease are consistent with what is known about the incidence and prevalence of diabetic nephropathy in these populations.

Spinal cord injury (SCI) is a devastating condition characterized by impaired motor and sensory function, as well as internal organ pathology and dysfunction. This internal organ dysfunction, particularly gastrointestinal (GI) complications, and neurogenic bowel, can reduce the quality of life of individuals with an SCI and potentially hinder their recovery. The gut microbiome impacts various central nervous system functions and has been linked to a number of health and disease states. An imbalance of the gut microbiome, i.e., gut dysbiosis, contributes to neurological disease and may influence recovery and repair processes after SCI. Here we examine the impact of high cervical SCI on the gut microbiome and find that transient gut dysbiosis with persistent gut pathology develops after SCI. Importantly, probiotic treatment improves gut health and respiratory motor function measured through whole-body plethysmography. Concurrent with these improvements was a systemic decrease in the cytokine tumor necrosis factor-alpha and an increase in neurite sprouting and regenerative potential of neurons. Collectively, these data reveal the gut microbiome as an important therapeutic target to improve visceral organ health and respiratory motor recovery after SCI.Competing Interest StatementThe authors have declared no competing interest.Footnotes* Correction to Figure 2a legend. Previously read \"Figure 2. Cervical SCI leads to acute dysbiosis and GI tract pathology. a, Principal coordinate analysis (PCoA) on Bray Curtis distances of normalized operational taxonomic units (OTUs) rarefied reads colored by day post-injury in surgical sham (square) or LC2Hx (circle) (permnova p = 0.0001).\" Corrected to \"Figure 2. Cervical SCI leads to acute dysbiosis and GI tract pathology. a, Principal coordinate analysis (PCoA) on Bray Curtis distances of normalized operational taxonomic units (OTUs) rarefied reads for all timepoints pre- and post-injury (pink = LC2Hx; blue = surgical sham; permnova p = 0.0001).\"

This chapter presents these microscope systems, along with brief descriptions of the science experiments driving the development of each system. Beginning with a discussion of the philosophy that has driven the Nanoscale Science Research Group (NSRG) and the methods used, the chapter describes the lessons learned during system development, including both useful directions and blind alleys. The first lesson is to begin software development at least as soon as hardware development. The second lesson is to partner with experts in required technologies. The NSRG attempts to use the best available computer technology to develop effective systems for use by the physical science team, which then become cost-effective and can be deployed on widely available hardware as technology marches on. The chapter also describes techniques to enable telemicroscopy in the context of remote experiments and outreach.