1,676 research outputs found

    Pupilla loessica LOŽEK 1954 (Gastropoda: Pulmonata: Pupillidae) - „A living Fossil“ in Central Asia?

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    LOŽEK (1986) vertritt die Ansicht, dass Pupilla loessica rezent in Zentralasien vorkommt. Die vorliegende Studie hat das Ziel zu diesem Thema erste konkrete Diskussionsbeiträge zu liefern. Zu verstehen ist diese Arbeit als Grundlage für weitergehende Untersuchungen. Bei neueren Geländeaufenthalten von 1995-2006 konnten in Zentralasien im Russischen Altay, in der nördlichen Mongolei, im Baikal-Gebiet und im Tien Shan zahlreiche rezente Malakozönosen untersucht werden. An vielen Lokalitäten wurde eine bisher aus dieser Region unbeschriebene Form von Pupilla nachgewiesen, welche gehäuse-morphologisch von Pupilla loessica nicht zu unterscheiden ist. Einen Schwerpunkt der Verbreitung bildet das stark kontinental geprägte Khrebet Saylyugem im SE-Altay. Für das Vorkommen von Pupilla loessica in Zentralasien spricht neben den gehäuse-morphologischen Kriterien, die Präferenz dieser Form zu stärker kontinental geprägten Habitaten, mit Jahresdurchschnittstemperaturen, die deutlich unter 0° C liegen sowie die entsprechenden kälteangepassten Begleitfaunen, z. B. mit Columella columella, Vertigo genesii, Vallonia tenuilabris u. a., welche diese Faunen gut mit den pleistozänen kaltzeitlichen Assoziationen des mitteleuropäischen Raumes vergleichbar machen.researc

    Adult nutrition and butterfly fitness: effects of diet quality on reproductive output, egg composition, and egg hatching success

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    <p>Abstract</p> <p>Background</p> <p>In the Lepidoptera it was historically believed that adult butterflies rely primarily on larval-derived nutrients for reproduction and somatic maintenance. However, recent studies highlight the complex interactions between storage reserves and adult income, and that the latter may contribute significantly to reproduction. Effects of adult diet were commonly assessed by determining the number and/or size of the eggs produced, whilst its consequences for egg composition and offspring viability were largely neglected (as is generally true for insects). We here specifically focus on these latter issues by using the fruit-feeding tropical butterfly <it>Bicyclus anynana</it>, which is highly dependent on adult-derived carbohydrates for reproduction.</p> <p>Results</p> <p>Adult diet of female <it>B. anynana </it>had pronounced effects on fecundity, egg composition and egg hatching success, with butterflies feeding on the complex nutrition of banana fruit performing best. Adding vitamins and minerals to a sucrose-based diet increased fecundity, but not offspring viability. All other groups (plain sucrose solution, sucrose solution enriched with lipids or yeast) had a substantially lower fecundity and egg hatching success compared to the banana group. Differences were particularly pronounced later in life, presumably indicating the depletion of essential nutrients in sucrose-fed females. Effects of adult diet on egg composition were not straightforward, indicating complex interactions among specific compounds. There was some evidence that total egg energy and water content were related to hatching success, while egg protein, lipid, glycogen and free carbohydrate content did not seem to limit successful development.</p> <p>Conclusion</p> <p>The patterns shown here exemplify the complexity of reproductive resource allocation in <it>B. anynana</it>, and the need to consider egg composition and offspring viability when trying to estimate the effects of adult nutrition on fitness in this butterfly and other insects.</p

    Conclusions about Niche Expansion in Introduced Impatiens walleriana Populations Depend on Method of Analysis

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    Determining the degree to which climate niches are conserved across plant species' native and introduced ranges is valuable to developing successful strategies to limit the introduction and spread of invasive plants, and also has important ecological and evolutionary implications. Here, we test whether climate niches differ between native and introduced populations of Impatiens walleriana, globally one of the most popular horticultural species. We use approaches based on both raw climate data associated with occurrence points and ecological niche models (ENMs) developed with Maxent. We include comparisons of climate niche breadth in both geographic and environmental spaces, taking into account differences in available habitats between the distributional areas. We find significant differences in climate envelopes between native and introduced populations when comparing raw climate variables, with introduced populations appearing to expand into wetter and cooler climates. However, analyses controlling for differences in available habitat in each region do not indicate expansion of climate niches. We therefore cannot reject the hypothesis that observed differences in climate envelopes reflect only the limited environments available within the species' native range in East Africa. Our results suggest that models built from only native range occurrence data will not provide an accurate prediction of the potential for invasiveness if applied to areas containing a greater range of environmental combinations, and that tests of niche expansion may overestimate shifts in climate niches if they do not control carefully for environmental differences between distributional areas

    Follow-up for breast cancer - the patients' view

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    Background: International and national guidelines (S3 guideline) for the surveillance of post-treatment breast cancer patients recommend a clinical follow-up including routine history and physical examination and regular mammograms. The practice of a clinical follow-up has been often discussed, but has been proven not to be inferior when compared to an intensified follow-up in randomized trials. Patients and Methods: The present manuscript reports the patients' view on the basis of a survey including 2000 patients with a history of breast cancer. Results: A total of 452 patients (22.6%) answered the questionnaire. The median age was 62 years (range 23-85 years). More than 80% of the patients were disease-free at the time of the survey. The need for surveillance was affirmed by the majority of patients (>95%), and one third stated that there was a need for more technical efforts during follow-up. In contrast to the follow-up guidelines, the results of the present survey indicated that most of the regularly scheduled follow-up visits were expanded using extensive laboratory and imaging procedures. Conclusion: This survey shows that the majority of physicians obviously do not accept the present follow-up guidelines. A new surveillance study investigating the efficacy of an intensified surveillance based on the improved possibilities of modern diagnostics and endocrine, immunotherapeutic, chemotherapeutic and interventional treatment options is warranted
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