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101.
To obtain initial data on Borrelia burgdorferi sensu lato (Spirochaetales: Spirochaetaceae) in Ixodes ricinus (Ixodida: Ixodidae) ticks in Hamburg, Germany, 1400 questing ticks were collected by flagging at 10 different public recreation areas in 2011 and analysed using probe‐based quantitative real‐time polymerase chain reaction. The overall rate of infection with B. burgdorferi s.l. was 34.1%; 30.0% of adults were infected (36.7% of females and 26.0% of males), as were 34.5% of nymphs. Significant differences in tick infection rates were observed between the spring and summer/autumn months, as well as among sampling locations. Borrelia genospecies identification by reverse line blotting was successful in 43.6% of positive tick samples. The most frequent genospecies was Borrelia garinii/Borrelia bavariensis, followed by Borrelia afzelii, Borrelia valaisiana, B. burgdorferi sensu stricto, Borrelia spielmanii, Borrelia bissettii and Borrelia lusitaniae. Based on previously published data, co‐infection of Borrelia and Rickettsiales spp. was determined in 25.8% of ticks. Overall, 22.9% of ticks were co‐infected with Rickettsia spp. (Rickettsiales: Rickettsiaceae), 1.7% with Anaplasma phagocytophilum (Rickettsiales: Anaplasmataceae), and 1.2% with both pathogens. Study results show a high prevalence of Borrelia‐positive ticks in recreation areas in the northern German city of Hamburg and the potential health risk to humans in these areas should not be underestimated.  相似文献   
102.
Cutaneous leishmaniasis (CL) is endemic to the Yucatan Peninsula of Mexico. The main causative agent is the parasite Leishmania mexicana (Biagi) (Kinetoplastida: Trypanosomatidae) and, based on the classic work of Dr Biagi's research team, it has been generally accepted and frequently reported that the only vector of L. mexicana in the region is the sandfly Lutzomyia olmeca olmeca (Vargas & Diáz‐Nájera) (Diptera: Psychodidae). Evidence gathered from recent entomological studies conducted mainly in Calakmul, Campeche, however, suggests that other species may also be vectors of L. mexicana. We conducted a field study in two villages in Calakmul, Campeche in the Yucatan Peninsula, where recent cases of CL have been reported, to document the species composition and relative abundances of the sandfly fauna and to identify which species are likely to be the main vectors by assessing the biting rates and parasite infection rates of the suspected vector species. Sandfly catches were conducted from November 2005 to February 2006 in Unión 20 de Junio and Dos Lagunas Sur. Sandflies were captured using Shannon (18.00–22.00 hours), Disney and CDC light traps (18.00–06.00 hours). Biting and infection rates were calculated for the four most abundant species: Lutzomyia cruciata (Coquillett), Lu. o. olmeca, Lutzomyia panamensis (Shannon) and Lutzomyia shannoni (Dyar). In Dos Lagunas Sur, Lu. panamensis and Lu. o. olmeca exhibited the highest biting rates throughout the sampling period. In Unión 20 de Junio, Lu. cruciata and Lu. o. olmeca had the highest biting rates over the same period. Regarding infection rates, we report herein the establishment of a polymerase chain reaction protocol and validation of IR1 and LM17 oligonucleotides to analyse the infection rates of sandflies. Out of 769 females analysed, the overall infection rates were 1.4% in Dos Lagunas Sur and 5.3% in Unión 20 de Junio. In Dos Lagunas Sur we found L. mexicana infections in two sandfly species, Lu. shannoni and Lutzomyia ylephiletor (Fairchild & Hertig), whereas in Unión 20 de Junio we found infections in Lu. shannoni, Lu. cruciata, Lu. o. olmeca and Lu. panamensis. The possible role of these four sandfly species in relation to L. mexicana transmission in Calakmul is discussed.  相似文献   
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A new genus of pleridosperms is described from the uppermost Devonian beds from Ballyheigue, Ireland. I.aceya hibernica May & Mat ten is represented by stems bearing spirally arranged fronds. The base of the frond is swollen and is about the same size as the stem. Pinnae are borne alternately and apparently in one plane on the rachis. The anatomy of the stem reveals a three-fluted protostele. Secondary xylem consists of rays and trachcids and secondary phloem is present. The inner cortex contains probable secretory and/or sclerotic cells. The outer cortex is of the spargaimm-type. Rachial trace formation is described. The U-shaped xylem strand of the rachis lacks secondary tissue. Pinnae traces are V- to C-shaped. A presumed adventitious root has a triarch protostele, a parenchymatous cortex and lacks a 'sparganum' outer zone. I.aceya is believed to be a member of the Lyginopleridaceae. The divisions of the sympodial protoxylem strand forming the rachial trace is compared among the Aneurophytales, Buteoxylonaceae, Calamopityaceae and Lyginopteridaceae and is shown to be similar.  相似文献   
106.
ABSTRACT. Oxygen consumption (O2) in six species of adult tiger beetles Cicindela spp. (Coleoptera: Cicindelidae) was correlated with body mass and temperature during rest. In beetles forced to run and/or right themselves continuously for 5–10 min at 25°C, O2 was approximately 7–12 times as high as in resting individuals; the difference increased with increasing mass. Resting and active VO2 were similar to previous results for other beetles, although the slope of log O2 on log mass was lower. Detailed analysis suggests the existence of taxonomic and ecological correlates of resting metabolism. The possible ecological implications and adaptive advantages of these results for adult tiger beetles are discussed.  相似文献   
107.
1. Plant defensive chemistry is predicted to have a more negative effect on generalist herbivores and their parasitoids than on specialist herbivores and their parasitoids. 2. This prediction was examined by comparing the effects of the wild parsnip (Pastinaca sativa L.) toxin, xanthotoxin, on a generalist herbivore–parasitoid association [the cabbage looper, Trichoplusia ni Hübner, and its polyembryonic parasitoid, Copidosoma floridanum (Ashmead)] and a specialist herbivore–parasitoid association [the parsnip webworm, Depressaria pastinacella (Duponchel), and its polyembryonic parasitoid, Copidosoma sosares (Walker)]. 3. Copidosoma floridanum brood sizes were smaller and experienced lower survivorship when reared in a host feeding on an artificial diet containing a low concentration of xanthotoxin. No T. ni hosts, parasitised or unparasitised, survived on a diet high in xanthotoxin. In contrast, C. sosares brood size and survivorship were unaffected by the presence of low levels of xanthotoxin in the host diet. Copidosoma sosares experienced reduced brood size and survivorship only when its host consumed a diet containing 15 times the level of xanthotoxin as the diet adversely affecting its congener. 4. The differences in response to xanthotoxin exhibited by C. floridanum and C. sosares are explained partly by a differential reduction in host quality and partly by differential exposure to xanthotoxin in host haemolymph. Unlike D. pastinacella, T. ni experienced reduced pupal weight and survivorship and prolonged developmental time on a low‐xanthotoxin diet. More xanthotoxin passed unmetabolised into the haemolymph of T. ni than into the haemolymph of D. pastinacella.  相似文献   
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