Localization and density of phoretic deutonymphs of the mite Uropoda orbicularis (Parasitiformes : Mesostigmata) on Aphodius beetles (Aphodiidae) affect pedicel length

The phoretic stage of Uropodina mites is a deutonymph with developed morphological adaptations for dispersal by insects. Phoretic deutonymphs are able to produce a pedicel, a stalk-like temporary attachment structure that connects the mite with the carrier. The aim of our study was to determine whether localization and density of phoretic deutonymphs on the carrier affect pedicel length. The study was conducted on a common phoretic mite-Uropoda orbicularis (Uropodina) and two aphodiid beetles-Aphodius prodromus and Aphodius distinctus. Our results show that pedicel length is influenced by the localization of deutonymphs on the body of the carrier. The longest pedicels are produced by deutonymphs attached to the upper part of elytra, whereas deutonymphs attached to femora and trochanters of the third pair of legs and the apex of elytra construct the shortest pedicels. In general, deutonymphs attached to more exposed parts of the carrier produce longer pedicels, whereas shorter pedicels are produced when deutonymphs are fixed to non-exposed parts of the carrier. A second factor influencing pedicel length is the density of attached deutonymphs. Mean pedicel length and deutonymph densities were highly correlated: higher deutonymph density leads to the formation of longer pedicels. The cause for this correlation is discussed, and we conclude that pedicel length variability can increase successful dispersal

When a beetle is too small to carry phoretic mites? A case of hydrophilid beetles (Coleoptera: Hydrophilidae) and <i>Uropoda orbicularis</i> (Acari: Mesostigmata)

The aim of our study was to determine the limit of a beetle’s body size below which it is not able to carry phoretic mites. We tested the hypothesis that body size of the carrier is the vital factor in selecting a host in mites with facultative and nonspecific phoresy. The study was conducted on beetles of the family Hydrophilidae and deutonymphs of the mite Uropoda orbicularis (Müller, 1776). Among 20 species of hydrophilids collected, only 7 carried deutonymphs. The smallest hydrophilids with body lengths below 2.32 mm did not carry deutonymphs. These were Cercyon analis (Paykull, 1798), Cercyon nigriceps (Marsham, 1802), Cercyon pygmaeus (Illiger, 1801), Cercyon terminatus (Marsham, 1802), Cryptopleurum crenatum (Kugelann, 1794), Cryptopleurum minutum (Fabricius, 1775), Cryptopleurum subtile Sharp, 1884, and Megasternum concinnum (Marsham, 1802). On the contrary, the largest beetles, of the genus Sphaeridium Fabricius, 1775, were most heavily and frequently occupied by phoretic deutonymphs. Most representatives of the genus Cercyon Leach, 1817 did not carry mites or had a very low mite burden. Our study indicates that beetle infestation by nonspecific phoretic mites is strongly influenced by beetle body size. </jats:p

Analysis of bus sustainability with regard to air-conditioning systems and energy consumption

W artykule przedstawiono wpływ zastosowania układów klimatyzacji różnej konstrukcji na ekologiczność i energochłonność autobusu miejskiego. Porównane zostały nowoczesne systemy, które charakteryzują się zastosowaniem innowacyjnych rozwiązań. Między innymi zbadano wpływ wykorzystania sprężarki napędzanej mechanicznie oraz sprężarki napędzanej silnikiem elektrycznym. Energochłonność określono na podstawie zużycia paliwa obliczonego metodą carbon balance. W pracy zaprezentowano również wyniki badań ekologiczności autobusów przeprowadzonych w teście jezdnym SORT 1 oraz podczas postoju pojazdu, gdzie jednostka spalinowa obciążana była przez włączenie układu klimatyzacji. W pomiarach wykorzystany został mobilny analizator spalin należący do grupy PEMS (Portable Emissions Measurement Systems). Urządzenie mierzyło stężenia związków szkodliwych oraz masowe natężenie przepływu gazów wylotowych. Ponadto podczas pomiarów rejestrowano temperatury wewnątrz pojazdu w celu określenia skuteczności działania danego rozwiązania.The paper presents a contrastive analysis of the co-relation between various air-conditioning systems and energy consumption in a bus with regard to its sustainalbility. Entire air-conditioning systems as well as their single parts were compared in the light of energy consumption expressed as the amount of fuel consumed by the bus. For example, the analysis included a comparison of mechanic and electric compressors. Fuel consumption was estimated with carbon balance method. Additionally, the paper presents the results of SORT 1 test conducted on a bus at stop while the combustion engine powered the air-conditioning system. Portable Emissions Measurement Systems (PEMS) were used in oredr to detect toxic compounds concentrations and the degree of exhaust flow. Morover, during the tests the temperature values inside the bus were recorded in order to assess the efficacy of each air-conditioning system or its single part that were used for comparison. All results were referred to the degree of city bus sustainability

Hitchhiking through life: a review of phoresy in Uropodina mites (Parasitiformes: Mesostigmata)

Several important papers discussing phoretic dispersal in animals have appeared in recent years, but the nature and evolutionary significance of the phenomenon are still not fully understood. This article reviews the current knowledge of this behaviour in Uropodina mites, which disperse at the deutonymphal stage. We first examine the morphological and behavioural attributes of Uropodina deutonymphs involved in phoretic dispersal. We then provide a systematic review of the animals that carry Uropodina, and examine the carrier-specificity of 30 well-known species. Most species are associated with a single family of carriers, or at most, two families. The available information shows that phoretic deutonymphs of most species do not show any preference for male or female carriers. The spatial pattern of attachment of phoretic deutonymphs varies according to the identity of the carrier insect. The nature of deutonymph infestation depends on the size and morphology of both the mite and its carrier. Successful phoresy also depends on synchronisation of the life cycles of the mite and its carrier, but the temporal dynamics of phoresy remain particularly poorly studied. Phoresy has ecological and evolutionary consequences for both the Uropodina and their carriers. Future research on phoresy will benefit from studies of its evolutionary development, the reasons why beetles appear to be specially favoured as carriers, how phoretic mites affect the insect that carries them, and how the apparent global decline in insect populations is affecting their symbiotic mites

Autobus elektryczny marki Solaris. Cz. 1

Zanieczyszczenie środowiska oraz obawa przed wyczerpaniem się zasobów paliwowych spowodowały podjęcie badań nad wykorzystaniem paliw alternatywnych. Coraz większe znaczenie mają pojazdy wykorzystujące energię elektryczną. Jednym z takich pojazdów jest autobus Solaris Urbino electric, który jest przedmiotem tego artykułu