Predator pheromone elicits a temporally dependent non-consumptive effect in prey

1. The influence of predator cues on the behaviour of prey is well supported in the literature; however, a clear understanding of how predator cues affect prey in variable environmental conditions and over longer time scales is needed to better understand the underlying mechanisms. Here, we measure how predator odors affect herbivore colonization, abundance, oviposition, and plant damage across two growing seasons.
2. The study system consisted of Leptinotarsa decemlineata (Colorado potato beetle) as prey, and the aggregation pheromone of live Podisus maculiventris (spined soldier bug) as the predator cue in a potato field.
3. In 2016, the amount of feeding damage by early beetle colonists was lower in predator odor-treated plots, reducing plant damage by 22%. Larval abundance was also reduced in treated plots in 2016. Beetle abundance and damage in 2017 was similar in the treatment and control plots. Two mechanisms were investigated to better understand why prey response to the predator odor treatment weakened over the first season, including changes in predator odor cue strength and prey habituation. Predator odor cue strength emerged as a likely explanation, as dispensers, which released a synthetic predator pheromone over the entire season, reduced the probability of finding damage more consistently than the live predator treatment.
4. These results suggest that temporal patterns of predator cue release and strength may drive prey response across the season, underscoring the importance of cue release-rate and consistency in both species interactions and for the future application of modifying insect behaviour using non-consumptive effects in agricultural systems.

     

When,during ontogeny,waxes in the blowfly (Calliphoridae) cuticle can act as phylogenetic markers

Cuticular compounds of three species of blowfly, Calliphora vomitoria (Linnaeus), Calliphora vicina (Robineau-Desvoidy) and Protophormia terraenovae (Robineau-Desvoidy), were analysed during ontogeny (eggs to 8-day-old adults) by gas chromatography. Discrimination among species is mainly due to quantitative rather than qualitative variations. Two different analytical approaches were used to judge if the cuticular hydrocarbons might be of interest as phylogenetic markers. Both methods, classical discriminant analysis and an original distance calculation method, led us to assume that the best phylogenetic congruence between cuticular compound profiles and both morphological and molecular phylogenies were found for young adult females.     

Metabolite diversification by cultivation of the endophytic fungus Dothideomycete sp. in halogen containing media: Cultivation of terrestrial fungus in seawater

The endophytic fungus, Dothideomycete sp. CRI7, isolated from the terrestrial plant, Tiliacora triandra, was salt tolerant, capable of growing in the culture medium prepared from seawater; salts in seawater did not have any effects on the fungal growth. Metabolite productions of the fungus CRI7 cultivated in media prepared from seawater (MSW), prepared from deionized water supplemented with potassium bromide (MKBr) or potassium iodide (MKI), and prepared from deionized water (MDW) were investigated. It was found that the cultivation of the fungus CRI7 in MKBr and MSW enabled the fungus to produce nine new metabolites (1–9). The production of an azaphilone, austdiol (10), of the fungus CRI7 grown in MDW was 0.04 g/L, which was much lower than that grown in MSW, MKBr, and MKI media which provided the yields of 0.5, 0.9, and 1.2 g/L, respectively, indicating that halogen salts significantly enhanced the production of the polyketide 10. The cultivation of terrestrial fungi in media containing halogen salts could therefore be useful for the metabolite diversification by one strain-many compounds (OSMAC) approach. Moreover, the isolated polyketides had significant biosynthetic relationship, suggesting that the cultivation of fungi in halogen containing media could provide the insights into certain polyketide biosynthesis. One of the isolated compounds exhibited antibacterial activity with the MIC value of 100 μg/mL.     

Algae as production systems of bioactive compounds

Algal extracts are gaining increasing interest due to their unique composition and possibilities of wide industrial applications. Various extraction techniques are used for conversion of algal biomass into extracts. Recently, attention of scientists has been paid to novel methods, such as enzyme‐assisted extraction, microwave‐assisted extraction, pressurized liquid extraction, supercritical fluid extraction, and ultrasound‐assisted extraction, which enable the extraction of biologically active compounds without their degradation. In this review, the properties of biologically active compounds extracted from the biomass of algae reported in the literature are presented in a structured way. Algal extracts contain compounds such as carbohydrates, proteins, minerals, oil, fats, polyunsaturated fatty acids as well as bioactive compounds such as antioxidants (polyphenols, tocopherols [vitamin E], vitamin C, mycosporine‐like amino acids), and pigments, such as carotenoids (carotene xanthophyll), chlorophylls, and phycobilins (phycocyanin, phycoerythrin), which possess antibacterial, antiviral, antifungal, antioxidative, anti‐inflammatory, and antitumor properties. Finally, we assemble a list of applications of algal extracts in different developing branches of agriculture (biostimulants, bioregulators, feed additives) and in pharmaceutical industry.     

Two-Electron Aromatics with Classical and Non-Classical Homobridges

Bishomotriborirane anions with a B-H-B bridge, 7, have been synthesized by a) protonation and b) methylation of bishomodianions, 3, as well as by c) hydride addition to 1,2,4-triboracyclopentanes, 15. Compounds 7 were characterized by ¹H, ¹³C and ¹¹B NMR spectroscopy and X-ray diffraction analyses. The suggested mechanism for the formation of 7 is supported by MP4SDTQ/6-311++G**//MP2(fc)/6-31+G* computations on [C₂B₃H₈]^- model compounds. Classical 1,2-dibora-4-borata-cyclopentane intermediates 16 undergo an intramolecular hydrogen shift to the B-B unit in their envelope conformation to give intermediates 17, which easily isomerize to 7. Relative energies for the parent compounds, 16u, 17u, 7u and the transition structures, TS-16/17u and TS-7/17u are predicted to be 30.7, 14.5, 0.0, 32.6 and 23.5 kcal mol^-1, respectively. The terms classical and non-classical homobridges are suggested for methylene and hydrogen bridges in 7 and in related compounds on the grounds of common building principles. The strength of homoaromaticity in 7u was estimated to be at least 23.5 kcal mol^-1, neglecting the much higher strain in 7u compared to TS-7/17u without a 3c2e bond.Electronic Supplementary Material available.     

N-Terminal Amino Acid Sequence of the Chlorophyll-binding Protein CP-47 of Photosystem 2 in the Thermophilic Cyanobacterium Synechococcus elongatus

Effects of caffeic acid and chlorogenic acid on mutagenicity were studied using the Salmonella typhimurium system. These compounds had inhibitory effects on the mutagenicity of Trp-P-1 and Glu-P-2. Caffeic acid completely eliminated the mutagenicity induced by activated Glu-P-2. Some compounds analogous to caffeic acid, such as cinnamic acid, coumaric acid, and ferulic acid, also significantly decreased the mutagenicity of Glu-P-2.     

Development of a novel algorithm for metal artifact reduction in digital tomosynthesis using projection-based dual-energy material decomposition for arthroplasty: A phantom study

In this study, a novel dual-energy (DE) material decomposition reconstruction algorithm (DEMDRA) was developed using projection data with the aim of reducing metal artifacts during digital tomosynthesis (DT) for implants. Using the three-material decomposition method and decomposition projection data specific for each material, a novel DEMDRA was implemented to reduce metal artifacts via weighted hybrid reconstructed images [maximum likelihood expectation maximization (MLEM) and shift-and-add (SAA)]. Pulsed X-ray exposures with rapid switching between low and high tube potential kVp were used for DE-DT imaging, and the images were compared using conventional filtered back projection (FBP), MLEM, the simultaneous algebraic reconstruction technique total variation (SART-TV), virtual monochromatic processing, and metal artifact reduction (MAR)-processing algorithms. The reductions in metal artifacts were compared using an artifact index (AI), Gumbel distribution of the largest variations, and the artifact spread functions (ASFs) for prosthesis phantom. The novel DEMDRA yielded an adequately effective overall performance in terms of the AI, and the resulting images yielded good results independently of the type of metal used in the prosthetic phantom, as well as good noise artifact removal, particularly at greater distances from metal objects. Furthermore, the DEMDRA represented the minimum in the model of largest variations. Regarding the ASF analysis, the novel DEMDRA yielded superior metal artifact reduction when compared with conventional reconstruction algorithms with and without MAR processing. Finally, the DEMDRA was particularly useful for reducing high-frequency artifacts.