271,811 research outputs found

    Efficacy of Different Pet Treat Formulations to Prevent Infestation by the Mite Tyrophagus putrescentiae

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    The pet food industry is a major part of the high-value processed food market in the USA and worldwide. Pest control associated with pet foods is an important activity. The mite Tyrophagus putrescentiae is a prolific cosmopolitan species that can infests high-value pet treats undetected until the infestations increase to very large numbers. Propylene glycol is a food-safe additive used to prevent mite infestations (Zhang et al., 2018; Abbar et al. 2015). Unfortunately, propylene glycol in certain foods can harm pets, and many companies are changing formulations. Here we conducted forced infestation of mites on three experimental pet treats and compared these to the current product that contains propylene glycol for susceptibility to mite infestation. We confirmed that the current product with propylene glycol did not support any mite population growth after a forced infestation with 20 mites. Two of the test formulations showed promise in preventing mite infestation, but one formulation was clearly susceptible to mites

    A comprehensive survey of Rhinonyssid mites (Mesostigmata: Rhinonyssidae) in Northwest Russia: New mite-host associations and prevalence data

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    Background: Rhinonyssid mites are permanent parasites of birds that inhabit their respiratory tract. There are around 600 species described worldwide and almost all species of birds are found to have embedded rhinonyssid mites. Despite their presumed relevance, these mites are largely unstudied due to the difficulty in sampling them and, therefore, the majority of mite-host associations and species-prevalence data are unknown. New information: In this study, 179 mite specimens belonging to 27 species and eight genera were identified. Notably, 18 new mite-bird associations were documented for the first time, thus increasing the known host range for these mite species. In addition, mite-host associations found in this study were compared with known associations from these species of birds in the European part of Russia and in Europe. Overall, this study represents the largest survey to date carried out on rhinonyssid mites in Russia and one of the most comprehensive datasets on rhinonyssid host-rang

    Screening for broad mite susceptibility in Rhododendron simsii hybrids

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    Broad mite Polyphagotarsonemus latus, is a key pest of pot azalea (Rhododendron simsii Planch hybrids). No information on variation in susceptibility or potential tolerance within these plants is available to date. We evaluated a selection of 32 Rhododendron cultivars, mainly Rhododendron simsii hybrids, for susceptibility to broad mite. The plants were artificially infested in a greenhouse by surrounding each azalea with four broad mite-infested English ivy plants (Hedera helix). Broad mite infestation was evaluated by counting the number of broad mites per shoot tip and assigning a damage rate. Results indicated a comparable infestation rate expressed as the number of mites on all cultivars at the initial stage of the experiments. Correlations between the average damage rate and the number of broad mites per shoot tip on all cultivars at different time intervals were significantly positive, although low, in each experiment, with R-2-values of 0.14 and 0.61. At the end of the experiments significant differences in susceptibility between the evaluated cultivars were observed. The cultivars, 'Emil De Coninck' and 'Mont Blanc' were rated as the most susceptible, whereas 'Mistral' and its bud sport 'Elien' were tolerant towards the broad mite, because damage rates were low and very few broad mites were found

    Sorting of Chiral Microswimmers

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    Microscopic swimmers, e.g., chemotactic bacteria and cells, are capable of directed motion by exerting a force on their environment. For asymmetric microswimmers, e.g., bacteria, spermatozoa and many artificial active colloidal particles, a torque is also present leading in two dimensions to circular motion and in three dimensions to helicoidal motion with a well-defined chirality. Here, we demonstrate with numerical simulations in two dimensions how the chirality of circular motion couples to chiral features present in the microswimmer environment. Levogyre and dextrogyre microswimmers as small as 50nm50\,\mathrm{nm} can be separated and selectively trapped in \emph{chiral flowers} of ellipses. Patterned microchannels can be used as \emph{funnels} to rectify the microswimmer motion, as \emph{sorters} to separate microswimmers based on their linear and angular velocities, and as \emph{sieves} to trap microswimmers with specific parameters. We also demonstrate that these results can be extended to helicoidal motion in three dimensions.Comment: 9 pages, 7 figure

    Computational toolbox for optical tweezers in geometrical optics

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    Optical tweezers have found widespread application in many fields, from physics to biology. Here, we explain in detail how optical forces and torques can be described within the geometrical optics approximation and we show that this approximation provides reliable results in agreement with experiments for particles whose characteristic dimensions are larger than the wavelength of the trapping light. Furthermore, we provide an object-oriented software package implemented in MatLab for the calculation of optical forces and torques in the geometrical optics regime: \texttt{OTGO - Optical Tweezers in Geometrical Optics}. We provide all source codes for \texttt{OTGO} as well as the documentation and code examples -- e.g., standard optical tweezers, optical tweezers with elongated particle, windmill effect, Kramers transitions between two optical traps -- necessary to enable users to effectively employ it in their research and teaching.Comment: 9 pages, 8 figure

    Resistance status of the carmine spider mite, Tetranychus cinnabarinus and the twospotted spider mite, Tetranychus urticae to selected acaricides on strawberries.

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    The carmine spider mite, Tetranychus cinnabarinus (Boisduval) and the twospotted spider mite, Tetranychus urticae Koch, are serious pests of strawberries and many other horticultural crops. Control of these pests has been heavily dependent upon chemical acaricides. Objectives of this study were to determine the resistance status of these two pest species to commonly used acaricides on strawberries in a year-round intensive horticultural production region. LC90 of abamectin for adult carmine spider mites was 4% whereas that for adult twospotted spider mites was 24% of the top label rate. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 0.5%, 0.5%, 1.4% and 83% of their respective highest label rates for carmine spider mite eggs, 0.7%, 2.7%, 12.1% and 347% of their respective highest label rates for the nymphs. LC90s of spiromesifen, etoxazole, hexythiazox and bifenazate were 4.6%, 11.1%, 310% and 62% of their respective highest label rates for twospotted spider mite eggs, 3%, 13%, 432,214% and 15% of their respective highest label rates for the nymphs. Our results suggest that T. cinnabarinus have developed resistance to bifenazate and that the T. urticae have developed resistance to hexythiazox. These results strongly emphasize the need to develop resistance management strategies in the region

    \u3ci\u3eEutarsopolipus Davidsoni\u3c/i\u3e N. Sp. (Acari: Podapolipidae) From \u3ci\u3eChlaenius Sericeus\u3c/i\u3e (Coleoptera: Carabidae) From Ingham County, Michigan, and Redescription of Male \u3ci\u3eEutarsopolipus Regenfussi\u3c/i\u3e

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    A new species of podapolipid mite from Michigan, Eutarsoplipus davidsani (Acari: Podapolipidae) is described, illustrated and compared with related species of Eutarsopolipus in the Myzus group. Eutarsopolipus davidsani is an ectoparasite of Chlaenius sericeus (Coleoptera: Carabidae). Keys to genera and groups of podapolipid mite parasites of Carabidae and keys to 11 species in the Myzus group of Eutarsopolipus are provided. The male stage of E. regenfussi Husband and Swihart 1986 is redescribed from specimens taken from the type host, Chlaenius pennsylvanicus

    Integration of biological mite control into outdoor strawberry production: a matter of efficacy and economy

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    Ten years experiences in experimental and practical fields prove that effective control of strawberry mite can be achieved by inundative introductions of the predatory mite Amblyseius cucumeris. Lately, Neoseiulus barkeri has been included to experiments compare its efficacy especially in higher strawberry mite densities

    Politik Media Dalam Membingkai Perempuan (Analisis Framing Pemberitaan Kasus Video Porno Yahya Zaini Dan Maria Eva Di Harian Umum Kompas Dan Suara Merdeka)

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    This research is a qualitative descriptive research which is aims to get an explanation about process of reality reconstruction doing by mass media, various kind of framing devices that is used, and woman representation at Kompas and Suara Merdeka news reporting about circulation of Yahya Zaini-Maria Eva porn video. In its execution, this research is using framing analysis method to gain information about way of mass media’s telling story. The data are collected by using qualitative content analysis applied to Kompas and Suara Merdeka news articles publish during December 2006. Unit of analysis determined based on Pan and Kosicki framing analysis model. Data validity is measured by triangulation technique. Data analysis is conducted by using the interactive data analysis technique. The result of this research shows that Kompas and Suara Merdeka have different point of view in reconstruction this case. Kompas showed careful news reporting while Suara Merdeka is more market oriented. Both of newspapers are uses same framing devices, including syntactic, script, thematic, and rhetoric. In representing woman, Kompas and Suara Merdeka are tending to frame woman in unfavorable ways
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