Search results for "Insecta"
showing 10 items of 265 documents
Comparison of quantitative Holocene temperature reconstructions using multiple proxies from a northern boreal lake
2017
Four biotic proxies (plant macrofossils, pollen, chironomids and diatoms) are employed to quantitatively reconstruct variations in mean July air temperatures ( Tjul) at Lake Loitsana (northern Finland) during the Holocene. The aim is to evaluate the robustness and biases in these temperature reconstructions and to compare the timing of highest Tjul in the individual reconstructions. The reconstructed Tjul values are evaluated in relation to local-scale/site-specific processes associated with the Holocene lake development at Loitsana as these factors have been shown to significantly influence the fossil assemblages found in the Lake Loitsana sediments. While pollen-based temperatures follow…
Flying insects: model systems in exercise physiology
1996
Insect flight is the most energy-demanding exercise known. It requires very effective coupling of adenosine triphosphate (ATP) hydrolysis and regeneration in the working flight muscles.31P nuclear magnetic resonance (NMR) spectroscopy of locust flight muscle in vivo has shown that flight causes only a small decrease in the content of ATP, whereas the free concentrations of inorganic phosphate (P i ), adenosine diphosphate (ADP) and adenosine monophosphate (AMP) were estimated to increase by about 3-, 5- and 27-fold, respectively. These metabolites are potent activators of glycogen phosphorylase and phosphofructokinase (PFK). Activation of glycolysis by AMP and P i is reinforced synergistica…
Modeling the insect mushroom bodies: application to a delayed match-to-sample task.
2013
Despite their small brains, insects show advanced capabilities in learning and task solving. Flies, honeybees and ants are becoming a reference point in neuroscience and a main source of inspiration for autonomous robot design issues and control algorithms. In particular, honeybees demonstrate to be able to autonomously abstract complex associations and apply them in tasks involving different sensory modalities within the insect brain. Mushroom Bodies (MBs) are worthy of primary attention for understanding memory and learning functions in insects. In fact, even if their main role regards olfactory conditioning, they are involved in many behavioral achievements and learning capabilities, as …
Update on the detection of beta-exotoxin in Bacillus thuringiensis strains by HPLC analysis.
2001
Aims: The current work aimed to study the presence of β-exotoxin by high-performance liquid chromatography (HPLC) in supernatant fluids from final whole cultures of the 69 type strains and 13 subtypes of Bacillus thuringiensis strains, as well as from some insecticidal strains. Methods and Results: Results from HPLC and bioassays with Ephestia kuhniella (Lepidoptera Pyralidae) were compared. Type I β-exotoxin was only detected in type strains representing serotypes H1, H9 and H10a,10b. Discrepancies between HPLC and bioassays were found in H8a,8b and some insecticidal strains, which suggests the occurrence of another soluble toxin different from type I β-exotoxin, possibly type II β-exotoxi…
Purification and analysis of polyhistidine-tagged human parvovirus B19 VP1 and VP2 expressed in insect cells
2008
Human parvovirus B19 is an autonomously replicating human pathogen with a specific tropism for human erythroid progenitor cells. There is an interest in producing empty nucleocapsids of B19 as they can be used as tools in molecular biology and diagnostics. Native B19 virus particles are formed from two structural viral proteins, VP1 and VP2. The VP2 protein alone is able to self assemble and consequently form virus-like particles (VLPs) in heterologous expression systems. Purification of recombinant VLPs has been conducted using various traditional methods. These include laborious and time-consuming, e.g. cesium chloride or sucrose gradient ultracentrifugation steps, allowing limited workin…
Essential Oils as Natural Biocides in Conservation of Cultural Heritage
2020
Essential oils (EOs) have been known for a long time, and they are used in several fields such as medicine and aromatherapy, as well as in the food and pharmaceutical industries. In the last decade, EOs have also been applied to contrast the biodeterioration of cultural heritage, representing a powerful resource in green conservation strategies. In this study, an integrated approach based on microscopic observation, in vitro culture, and molecular investigation was preliminarily employed to identify biological systems colonizing wooden artworks. In order to contrast the biodeterioration processes induced by fungal colonization (Aspergillus flavus) or insect infestation (Anobium punctatum), …
Postembryonic development of the troglobitic planthopper species Valenciolenda fadaforesta Hoch & Sendra, 2021 (Hemiptera, Fulgoromorpha, Ki…
2022
All nymphal instars of the recently discovered troglobitic planthopper species Valenciolenda fadaforesta Hoch & Sendra, 2021 are described. This represents the first documentation of the complete postembryonic development of any species in the family Kinnaridae. Characters of the external morphology are described and illustrated, and a key to the instars are provided to facilitate discrimination among the different nymphal stages. While V. fadaforesta nymphs share certain synapomorphies with other Fulgoromorpha (except the Tettigometridae), e.g., the cog-wheel structures of the metatrochanters, other characters may be correlated with the subterranean way of life of the species, and thus…
Metabolism of Thiodan® in Insects
1966
Two new species of Brusqeulia Razowski & Becker, 2000 from the Neotropics, with comments on the systematic position of the genus in relation to the A…
2018
Two new species of the neotropical genus Brusqeulia Razowski & Becker, 2000, are described and illustrated: B. yunkensis Pérez Santa-Rita & Baixeras, sp. n. from Bolivia and B. araguensis Pérez Sant-Rita & Baixeras, sp. n. from Venezuela. The systematic position and diagnostic characters of the genus are reviewed, resulting in the synonymy of Pinhaisania Razowski & Becker, 2000, with Brusqeulia, and the combination B. crispula (Razowski & Becker, 2000), comb. n. New characters of the female genitalia are discussed.
Degenerative and regenerative processes involved in midgut pseudotumor formation in the stick insect (Carausius morosus)
2009
Spontaneous and experimentally induced pseudotumor formation in Carausius morosus impairs the midgut tissue homeostasis. Spontaneous pseudotumor formation begins by the break down of a single or a small group of columnar cells (CCs) and is followed by the degeneration of neighboring CCs. There are not only marked similarities but also decisive differences between normal dying CCs in healthy specimens and the degeneration of CCs leading to pseudotumors: in both cases, the apical cell parts with the nucleus are extruded into the midgut lumen, but only during of pseudotumor formation an "amorphous substance" originates from the basal parts of the CCs. Hemocytes are attracted to this substance …