660 research outputs found
Human behaviour and application of residual insecticides to control storage and food industry pests
We measured the individual variation of the area-estimate of simple geometrical patterns (circle, rectangle) in ten people. We found that they tended to underestimate (max. 5 x) the correct area of the tested geometrical patterns. Consequently, we explored how the insecticides Ficam 80WP, K-Othrine 25, and Actellic EC50 are robust or sensitive to the measured extent of over-dosage (2x) or underdosage (5x). We also tested the effects of incorrect dosages of insecticides applied to porous filter paper nonporous glass and bioassayed with adult Sitophilus oryzae and Tribolium castaneum. We found that the tested insecticides were surprisingly robust to under-dosage on the glass surface but sensitive to under-dosage on the porous paper surface. Keywords: Pesticides, Insecticides, Residual treatment, Dosage, Human behaviou
Liotryphon punctulatus (Ratzeburg, 1848) (Hymenoptera: Ichneumonidae) – a parasitoid of Ephestia kuehniella larvae
Until now, there has been no record of Liotrophon punctulatus (Hymenoptera: Ichneumonidae) presence in the anthropogenic environment of mills, bakeries or pasta factories. This is the first report of the species parasitizing Ephestia kuehniella (Lepidoptera: Pyralidae) larvae. The host/parasitoid interaction was validated under laboratory conditions where fourth or fifth instar larvae of Ephestia kuehniella were provided ad libitum to L. punctulatus females. After two filial generations emergence, the validation process was considered to confirm the interaction. Keywords: Liotrophon punctulatus, Parasitoid, Ephestia kuehniell
External egg morphology of common stored-product pests from the families Anobiidae (Ptininae) and Dermestidae (Coleoptera)
External egg morphology of some common stored-product pests from the families Anobiidae (Ptininae: Ptinus, Niptus) and Dermestidae (Trogoderma, Reesa) based on optical and scanning electron microscope (SEM) micrographs are presented. Diagnostic characteristics are described. Differences in the eggs of these families, genera and some species were found with respect to shape, size and surface structures. Keywords: Egg morphology, SEM micrographs, Stored-product pest identificatio
How methodical approaches affects results of pest sampling in stores and counting in laboratory
Emerging risk of infestation and contamination of dried fruits by mites in the Czech Republic
Fluorescent non-toxic bait as a new method for black rat (Rattus rattus) monitoring
The detection of synathropic rodents may be difficult since they are animals with nocturnal activity. Methods of their detection and monitoring rely mostly on indirect signs of their activity such as the presence of faeces, urine, consumed foods and damaged materials. Our experimental hypothesis was that the production of fluorescent faeces - following consumption of fluorescent bait - may be used for rodent monitoring. For this purpose we studied the production of fluorescent faeces, temporal dynamics and detectability in wild black rat (Rattus rattus). Wild black rats were individually housed in experimental cages with the wire-mesh grid floor and faeces were collected in short-time intervals. The peak of fluorescent activity in faeces was detected 10-20 hours after bait ingestion. We found that there is only relatively short delay between bait consumption and defecation and fluorescent faeces are easily detectable at distance using an ultraviolet hand lamp. Thus, this method can contribute to effective monitoring of rodent pests.Keywords: Rattus rattus, Fluorescent bait, Monitoring, Rodent contro
Innovation Collaborations of Firms: the Case of Hungarian Multinational Companies
Multinational companies (MNCs) are geographically widespread production networks that can coordinate operations and activities in more than one country. MNCs transfer innovations, expertise, knowledge and advanced technologies to their host countries through their subsidiaries. Therefore, multinational companies are seen as transfer intermediaries distributing international technologies and innovations. MNCs help to bridge the existing technology gap between developed and developing countries. Due to the multilocation nature of MNCs, the study aims to examine the various drivers that influence Hungarian MNCs' R&D collaborations, making them choose to collaborate either with local partners or with partners in the countries of their headquarters. The paper reports on the preliminary findings of an on-going comparative research focused on understanding the key drivers of innovations and competitiveness in Hungary. For our empirical analysis, drawing on data from the Eurostat's harmonized Community Innovation Survey 2010-2012, we used the probit regression model. Since many studies have shown that innovation processes in companies are based on the same principles or similar framework, it is possible to generalize the results of the analysed data and successfully put the recommendations into practice. Our analysis provided mixed results; it has demonstrated that marketing orientations, expenditures devoted to research and development, absorptive capacity, firm size as well as funding support provided to Hungarian MNCs influenced their choice of collaborating partners. Hungarian MNCs were highly probable to collaborate with both local and foreign partners in the enterprise group, while preferring to cooperate with local universities rather than foreign ones. © Odei S. A., Prokop V., Stejskal J. Text. 2020.The article work has been prepared with the support of the grant No. 17-11795S provided by the scientific research project of the Czech Science Foundation
Low Carbon Steel Processed by Equal Channel Angular Warm Pressing
Low carbon steel AISI 10 was subjected to a severe plastic deformation technique called Equal Angular Channel Pressing (ECAP) at different increased temperatures. The steel was subjected to ECAP with channel’s angle j = 90°, at different temperature in range of 150 - 300 °C. The number of passes at each temperature was N = 3. Light, scanning electron microscopy (SEM) and transmission electron microscopy (TEM) of thin foils were used to study the formation of substructure and ultrafine grains in deformed specimens. The size of newly born polygonized grains (subgrains and/or submicrocrystalline grains) is in range of 300 - 500 mm. The formation of such of predominant submicrocrystalline structure resulted in significant increase of yield stress [Re] and tensile strength of the steel [Rm]
Properties of small molecular drug loading and diffusion in a fluorinated PEG hydrogel studied by ^1H molecular diffusion NMR and ^(19)F spin diffusion NMR
R_f-PEG (fluoroalkyl double-ended poly(ethylene glycol)) hydrogel is potentially useful as a drug delivery depot due to its advanced properties of sol–gel two-phase coexistence and low surface erosion. In this study, ^1H molecular diffusion nuclear magnetic resonance (NMR) and ^(19)F spin diffusion NMR were used to probe the drug loading and diffusion properties of the R_f-PEG hydrogel for small anticancer drugs, 5-fluorouracil (FU) and its hydrophobic analog, 1,3-dimethyl-5-fluorouracil (DMFU). It was found that FU has a larger apparent diffusion coefficient than that of DMFU, and the diffusion of the latter was more hindered. The result of ^(19)F spin diffusion NMR for the corresponding freeze-dried samples indicates that a larger portion of DMFU resided in the R_f core/IPDU intermediate-layer region (where IPDU refers to isophorone diurethane, as a linker to interconnect the R_f group and the PEG chain) than that of FU while the opposite is true in the PEG–water phase. To understand the experimental data, a diffusion model was proposed to include: (1) hindered diffusion of the drug molecules in the R_f core/IPDU-intermediate-layer region; (2) relatively free diffusion of the drug molecules in the PEG-water phase (or region); and (3) diffusive exchange of the probe molecules between the above two regions. This study also shows that molecular diffusion NMR combined with spin diffusion NMR is useful in studying the drug loading and diffusion properties in hydrogels for the purpose of drug delivery applications
- …