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Relationships within satyrine butterflies have been notoriously difficult to resolve using both morphology and Sanger sequencing methods, and this is particularly true for the mainly Neotropical subtribe Euptychiina, which contains about 400 described species. Known larvae of Euptychiina feed on grasses and sedges, with the exception of the genus Euptychia, which feed on mosses and lycopsids, and the butterflies occur widely in rainforest, cloudforest and grassland habitats, where they are often abundant. Several previous molecular and morphological studies have made significant progress in tackling the systematics of the group, but many relationships remain unresolved, with long-branch-attraction artifacts being a major problem. Additionally, the monophyly of the clade remains uncertain, with Euptychia possibly not being closely related to the remainder of the clade. Here we present a backbone phylogeny of the subtribe based on 106 taxa, 368 nuclear loci, and over 180,000 bps obtained through hybrid enrichment. Using both concatenation and species tree approaches (IQ-TREE, EXABAYES, ASTRAL), we can for the first time strongly confirm the monophyly of Euptychiina with Euptychia being the sister group to the remainder of the clade. The Euptychiina is divided into nine well supported clades, but the placement of a few genera such as Hermeuptychia, Pindis and the Chloreuptychia catharina group still remain uncertain. As partially indicated in previous studies, the genera Cissia, Chloreuptychia, Magneuptychia, Megisto, Splendeuptychia and Euptychoides, among others, were found to be highly polyphyletic and revisions are in preparation. The phylogeny will provide a strong backbone for the analysis of datasets in development that are much more taxonomically comprehensive but have orders of magnitude fewer loci. This study therefore represents a critical step towards resolving the higher classification and studying the evolution of this highly diverse lineage.

Predators can have strong influences on ecological processes through impacts on individuals at lower trophic levels, and changes in predator-prey dynamics can alter ecosystem functioning. However, much of what we currently know about interactions across trophic levels comes from mesic or relatively fertile systems, with fewer studies examining trophic interactions and resulting ecosystem processes in arid or infertile systems. To address this knowledge gap, we excluded avian predators from shrubs during the growing season using netting in a sagebrush steppe environment. We compared arthropod abundance, shrub herbivory damage, physiology (gas exchange and chlorophyll fluorescence), litter chemistry (C/N ratios and concentrations of phenolic compounds) and decomposition between netted and un-netted (control) sagebrush (Artemisia tridentata ssp. wyomingensis) shrubs across a growing season. While there were clear seasonal patterns in measurements, we observed no statistically significant differences between netting treatments in any of these measurements, though abundances of arthropods in the sap-feeding trophic guilds were appreciably greater (although not significantly) on netted compared to un-netted shrubs. Our results suggest that in the short-term, either top-down effects in this sage-steppe ecosystem are minimal, and/or inter-trophic interactions (vertebrate predators-arthropods-plants) are relatively weak and more dependent on bottom-up processes that are linked with abiotic variables.

The Neotropical moth-like butterflies (Hedylidae) are perhaps the most unusual butterfly family. In addition to being species-poor, this family is predominantly nocturnal and has anti-bat ultrasound hearing organs. Evolutionary relationships among the 36 described species are largely unexplored. A new, target capture, anchored hybrid enrichment probe set (‘BUTTERFLY2.0’) was developed to infer relationships of hedylids and some of their butterfly relatives. The probe set includes 13 genes that have historically been used in butterfly phylogenetics. Our dataset comprised of up to 10,898 aligned base pairs from 22 hedylid species and 19 outgroups. Eleven of the thirteen loci were successfully captured from all samples, and the remaining loci were captured from ≥94% of samples. The inferred phylogeny was consistent with recent molecular studies by placing Hedylidae sister to Hesperiidae, and the tree had robust support for 80% of nodes. Our results are also consistent with morphological studies, with Macrosoma tipulata as the sister species to all remaining hedylids, followed by M. semiermis sister to the remaining species in the genus. We tested the hypothesis that nocturnality evolved once from diurnality in Hedylidae, and demonstrate that the ancestral condition was likely diurnal, with a shift to nocturnality early in the diversification of this family. The BUTTERFLY2.0 probe set includes standard butterfly phylogenetics markers, captures sequences from decades-old museum specimens, and is a cost-effective technique to infer phylogenetic relationships of the butterfly tree of life.

Host species utilize a variety of defenses to deter feeding, including secondary chemicals. Some phytophagous insects have evolved tolerance to these chemical defenses, and can sequester secondary defense compounds for use against their own predators and parasitoids. While numerous studies have examined plant-insect interactions, little is known about lichen-insect interactions. Our study focused on reconstructing the evolution of lichen phenolic sequestration in the tiger moth tribe Lithosiini (Lepidoptera: Erebidae: Arctiinae), the most diverse lineage of lichen-feeding moths, with 3000 described species. We built an RNA-Seq dataset and examined the adult metabolome for the presence of lichen-derived phenolics. Using the transcriptomic dataset, we recover a well-resolved phylogeny of the Lithosiini, and determine that the metabolomes within species are more similar than those among species. Results from an initial ancestral state reconstruction suggest that the ability to sequester phenolics produced by a single chemical pathway preceded generalist sequestration of phenolics produced by multiple chemical pathways. We conclude that phenolics are consistently and selectively sequestered within Lithosiini. Furthermore, sequestration of compounds from a single chemical pathway may represent a synapomorphy of the tribe, and the ability to sequester phenolics produced by multiple pathways arose later. These findings expand on our understanding of the interactions between Lepidoptera and their lichen hosts.

Predators can induce extreme stress and profound physiological responses in prey. Insects are the most dominant animal group on Earth and serve as prey for many different predators. Although insects have an extraordinary diversity of anti-predator behavioral and physiological responses, predator-induced stress has not been studied extensively in insects, especially at the molecular level. Here, we review the existing literature on physiological predator-induced stress responses in insects and compare what is known about insect stress to vertebrate stress systems. We conclude that many unrelated insects share a baseline pathway of predator-induced stress responses that we refer to as the octopamine-adipokinetic hormone (OAH) axis. We also present best practices for studying predator-induced stress responses in prey insects. We encourage investigators to compare neurophysiological responses to predator-related stress at the organismal, neurohormonal, tissue, and cellular levels within and across taxonomic groups. Studying stress-response variation between ecological contexts and across taxonomic levels will enable the field to build a holistic understanding of, and distinction between, taxon- and stimulus-specific responses relative to universal stress responses.

Poly(ethylene oxide) (PEO)-modified myoglobin (PEO–Mb) was immobilized on a carbon electrode with the aid of polyelectrolytes, and the redox response was successively analyzed in salt-containing PEO oligomers. Complexation of PEO–Mb with poly- l -lysine was found to be quite effective in maintaining a constant peak current in cyclic voltammograms for more than 20 h, but the peak current gradually decreased at 50°C. Addition of poly- l -glutamic acid or their polyion complex was less effective to fix the PEO–Mb on the electrode. PEO–Mb was fixed through electrostatic interaction between PEO–Mb and poly- l -lysine. In order to achieve more stable redox activity of Mb in PEO oligomers, covalent immobilization of Mb to electrode surface was attempted. In this work, the maleic anhydride unit in the PEO–maleic anhydride copolymer was initially used to fix the Mb, followed by an ester formation between newly generated carboxylic groups and hydroxyl groups on the electrode surface. A stable redox response was obtained, and this effective immobilization of Mb on the electrode has yielded thermally stable redox response for 30 h even at 80°C without denaturation nor elution of Mb into PEO oligomers.

The native azurin (Az) was chemically modified with activated poly(ethylene oxide) (PEO) to solubilize in the PEO oligomers. PEO 2000 (average molecular weight of 2000)-modified Az (PEO 2000 -Az) was dissolved without denaturation in PEO 200 (average molecular weight of 200). The electronic absorption spectrometry exhibited no detectable conformational change of PEO 2000 -Az in phosphate buffer. The electron paramagnetic resonance (EPR) spectrum of PEO 2000 -Az is also quite similar to that of native Az in water. This result confirms that the chemical modification with PEO 2000 does not cause any structural change around the copper site. Moreover, since no changes in the EPR spectrum are observed in PEO 200 , the copper coordination geometry must be maintained even in PEO 200 . The redox activity of PEO 2000 -Az in PEO 200 (containing 0.5 mol dm −3 NaClO 4 ) was investigated by cyclic voltammetry. When we use the PEO 350 -SH (α-methoxy-ω-mercapto-poly(ethylene oxide); PEO with average molecular weight of 350) modified gold electrode as a working electrode, the redox response was observed in PEO 200 . The result of the measurements for the scan rate dependence suggests that PEO 2000 -Az could be immobilized on the PEO 350 -SH modified electrode.

The reaction of Bi4Ti3O12−x with lithium iodide under an atmosphere of iodine at 350°C was found to afford an intercalation compound LiI3Bi4Ti3O11−x in high yield. The new bismuth titanate is brownish red in color and formed in an orthorhombic cell with the lattice parameters of a=5.912 (1), b=5.256 (1), and c=36.889 (8) A. The pathway to the new intercalation compound is proposed on the basis of X-ray, XPS, SEM, and compositional observations.

Double-stranded short-chain DNA was covalently bound to hemin, and was incorporated into the heme pocket of apo-myoglobin. Then this was further modified with activated poly(ethylene oxide). Thus, prepared PEO-Mb(DNA) was soluble and electrochemically redox active in PEO oligomers. Enhancement of the electron transfer reaction was not observed for the mixture of PEO-Mb and long-chain DNA. However, the charge of PEO-Mb(DNA) was found to be larger than that of PEO-Mb in PEO oligomer. It was suggested that the short-chain DNA was effective to be a molecular wire in the PEO.

Poly(ethylene oxide)-modified human hemoglobin (PEO-Hb) was cast on the indium tin oxide (ITO) glass electrode from aqueous solution, and the dried electrode was soaked into salt-containing PEO oligomers (MW:400, 600, 1000). Their redox reaction was investigated with both cyclic voltammetry and UV-vis spectrophotometry at wide temperature from 30 to 160°C. The electron transfer reactions of PEO-Hb cast on the ITO glass electrode were clearly detected in PEO oligomer (MW:400) at temperatures from 30 to 140°C with cyclic voltammetry. The extraordinary thermal stability of PEO-Hb on the ITO glass electrode was observed in only PEO oligomers as a solvent which was never seen in buffer solution. The thermal stability was improved by increasing the molecular weight of solvent PEO. The absorbance at Soret band for PEO-Hb was quite stable for 10 h at 80°C in PEO1000 (MW:1000). PEO-Hb on the ITO glass electrode was also stable for 3 h at 120°C, but denatured gradually at 140°C in PEO1000.

Horse heart cytochrome c (cyt.c) was modified with poly(ethylene oxide) (PEO) to solubilize it in PEO oligomers. The electrochemical redox reaction of PEO-modified cyt.c (PEO-cyt.c) was analyzed with visible spectrometry in PEO200 (average molecular weight of 200) containing 0.5 mol · 1 −1 KC1 as an electrolyte. Although the PEO-cyt.c showed redox reaction in PEO200, the apparent rate constant of PEO-cyt.c was much smaller than that of PEO-modified hemoglobin and PEO-modified myoglobin in PEO200. The degree of PEO-modification did not affect the reduction rate constant of PEO-cyt.c in PEO200. The circular dichroism (CD) spectrometry showed no detectable conformational change of PEO-cyt.c in phosphate buffer. On the other hand, CD spectra of PEO-cyt.c in PEO200 were different from those in phosphate buffer. This conformational change might be the reason for slow electrode reduction of PEO-cyt.c in PEO200.

A study was made of the induction of drug-metabolizing enzyme activity and the effect of the induced activity on the duration of drugs in fish. Carp were fed with a diet containing PCB ( 0.1 mg PCB 100 g body weight day −1 ) for 2 weeks to induce drug-metabolizing enzymes. After pretreatment, oxolinic acid, thiamphenicol and oxytetracycline were administered in feed to PCB-treated and nontreated (as control) fish as a single dose of 20, 50, and 50 mg/kg body weight, respectively. The peak concentrations of oxolinic acid in the blood, kidney, liver, and muscle of fish in the PCB group were lower than the half of those in the controls. Furthermore, the duration times of oxolinic acid in the tissues of PCB-treated fish were also shorter than those in the control. However, the duration of thiamphenicol and oxytetracycline showed no significant changes relating to PCB treatment.

In cultured vascular smooth muscle cells, interferon gamma (IFN-gamma) induced the accumulation of nitrite, a stable metabolite of nitric oxide, in a dose- and time-dependent manner. In parallel with this reaction, this cytokine increased the mRNA and protein levels of an inducible macrophage-type of nitric oxide synthase (iNOS). Forskolin, a direct activator of adenylate cyclase, or dibutyryl cAMP alone caused small increases in nitrite accumulation and iNOS mRNA and protein levels and synergistically enhanced the IFN-gamma-stimulated reactions. 8-Bromo-cGMP neither increased by itself nor synergized with IFN-gamma to increase the same reactions. Prostaglandin E1 and beraprost, a stable analogue of prostaglandin I2, which by themselves showed only marginal effects on these reactions, also synergized with IFN-gamma to stimulate the reactions. Interleukin 1 beta or tumor necrosis factor alpha stimulated the same reactions which were similarly enhanced by forskolin. These results indicate that an elevation of intracellular cAMP, particularly in combination with inflammatory cytokines, positively regulates nitric oxide production at the level of iNOS mRNA expression in vascular smooth muscle cells.