898 research outputs found
AFLPs: genetic markers for paternity studies in newts (Triturus vulgaris)
DNA-based genetic markers can reveal paternity whenever the direct assignment of fathers to offspring is precluded by multiple matings and internal fertilisation. Microsatellites are the current marker of choice in many behavioural studies, and have revealed important insights into genetic mating systems of European amphibians. However, the number of amphibian species for which the time-consuming designing of locus-specific microsatellite primers was successful is still limited, and the cross-utilisation of existing markers to closely related taxa seems to have a particularly low success rate. Allozymes can infer parentage without a species-specific protocol, but, due to their low degree of polymorphism, in mate choice experiments require the a priori screening of individuals. Dominant markers such as RAPDs successfully identified closely-related amphibian species and their hybrids, but might be less suited to distinguish between closely related individuals with a putatively high frequency of shared bands
Hierarchically-structured metalloprotein composite coatings biofabricated from co-existing condensed liquid phases
Complex hierarchical structure governs emergent properties in biopolymeric materials; yet, the material processing involved remains poorly understood. Here, we investigated the multi-scale structure and composition of the mussel byssus cuticle before, during and after formation to gain insight into the processing of this hard, yet extensible metal cross-linked protein composite. Our findings reveal that the granular substructure crucial to the cuticle’s function as a wear-resistant coating of an extensible polymer fiber is pre-organized in condensed liquid phase secretory vesicles. These are phase-separated into DOPA-rich proto-granules enveloped in a sulfur-rich proto-matrix which fuses during secretion, forming the sub-structure of the cuticle. Metal ions are added subsequently in a site-specific way, with iron contained in the sulfur-rich matrix and vanadium coordinated by DOPA-catechol in the granule. We posit that this hierarchical structure self-organizes via phase separation of specific amphiphilic proteins within secretory vesicles, resulting in a meso-scale structuring that governs cuticle function
SuDS and amphibians - are constructed wetlands really benefitting nature and people?
While urbanisation is a major threat to global
biodiversity, it also brings opportunities for some
species. Sustainable Drainage Systems (SuDS) have
been installed in all Scottish cities to reduce flood
and pollution risk and they can also offer new
habitats for wildlife. We studied SuDS in Inverness
and the Scottish Central Belt to assess their value as
amphibian breeding sites, habitats, and as places
where urban people can experience nature. The
nine-year study revealed that many SuDS were of
similar ecological quality to wider countryside ponds
but that the quality of ponds is not equitably
distributed between neighbourhoods inhabited by
different socio-economic classes. However, the
findings suggest ways to improve the design and
management of SuDS for people and nature, making
access to high quality ponds available to all social
groups
Biologische Kontrolle von Eulenraupen im Kohl mittels Baculoviren
Baculoviren sind als hoch selektive biologische Kontrollagenzien für Kohleulenraupen (Mamestra brassicae) seit längerem bekannt und ihre gute Wirksamkeit wurde schon in verschiedenen Gewächshaus- und Freilandversuchen nachgewiesen. Um die Kontrollsituation von Kohleulenraupen im ökologischen Gemüseanbau insbesondere bei niedrigen Temperaturen zu verbessern, wurden die eulenpathogenen Mamestra brassicae Nukelopolyhedrovirus (MbMNPV) und Mamestra configurata Nukleopolyhedrovirus (MacoNPV-A) als mögliche Kontrollagentien geprüft. Es konnte gezeigt werden, dass auch MacoNPV-A für M.brassicae pathogen ist. In vergleichenden Bioassays bei 24°C zeigten MbMNPV und MacoNPV-A keinen signifikanten Unterschied hinsichtlich ihrer biologischen Aktivität gegenüber M.brassicae. In weiteren Bioassays wurden die konzentrationsabhängige Mortalität von M.brassicae im 2. Larvenstadium sowie die gefressene Blattfläche bei 24, 20, 16 und 12°C bestimmt. Im Vergleich zu 24 und 20°C waren die mittleren Letalkonzentrationen bei 16 und 12°C 100 bzw. 1000fach höher. Für eine mittlere Reduktion der konsumierten Blattfläche waren hingegen bei Temperaturen unter 20°C 10 bis 100fach höhere Konzentrationen notwendig. Durch die Neuformulierung von MbMNPV (Probis GmbH, Wiernsheim) konnte eine Wirkungssteigerung im Vergleich zu der nicht formulierten Virussuspension im Bioassay erzielt werden. In einem Freilandtest mit künstlicher Infestation in Kohlrabi konnte eine weitere Steigerung des Wirkungsgrades durch die Kombination mit dem Bacillus thuringiensis Präparat XenTari® im Vergleich zur Einzelapplikation der beiden Präparate erreicht werden. Eine breite Freilandtestung der Baculoviren-Präparaten gegen Kohlraupen bei kühler Witterung als Einzelpräparat und in Kombination mit Bacillus thuringiensis Präparaten sowie neuester Applikationstechnik für Ober- und Unterblattbehandlung wird empfohlen
Authentic Borna disease virus transcripts are spliced less efficiently than cDNA-derived viral RNAs
Borna disease virus (BDV) is a non-segmented, negative-strand RNA virus that replicates and transcribes its genome in the nucleus of infected cells. It uses the cellular splicing machinery to generate a set of alternatively spliced mRNAs from the 2.8 and 7.1 kb primary transcripts, each harbouring two introns. To determine whether splicing of these transcripts is regulated by viral factors, the extent of splicing was studied in infected cells and COS-7 cells transiently transfected with plasmids encoding the 2.8 kb RNA of BDV. Unspliced RNA was found to be the most abundant RNA species in infected cells, whereas viral transcripts lacking both introns were only found in minute amounts. In sharp contrast, plasmid-derived 2.8 kb RNA was predominantly intron 1-spliced and double-spliced. Co-expression of the BDV proteins P, N and X did not influence splicing of plasmid-expressed 2.8 kb RNA. Furthermore, the splicing pattern did not change when the 2.8 kb RNA was expressed in BDV-infected cells. Based on these results we speculate that splicing of authentic BDV transcripts is tightly linked to transcription by the viral polymerase
Analysis of Subsurface Gravel Layer Flow caused by Turbulent Open Channel Flow using 3-D PTV and Pressure Sensor Techniques (Untersuchung der Interaktion von Haupt- und Interstitialströmung mit Hilfe von 3-D PTV und piezoresistiven Drucksensoren)
Effekten av olika koncentrationer av Rotstop R och Rotstop S och ofullständig täckning av Rotstop S på sporinfektioner av rotticka på granstubbar
The effectiveness of treatment with two Phlebiopsis gigantea based preparations (Rotstop®
and RotstopS) in different concentrations against the root and butt rot causing fungus
Heterobasidion annosum s.l. on Norway spruce (Picea abies) thinning stumps in southern
Sweden was compared. The trees were cut on three sites during the summer 2004 and 285
stumps were treated manually with 100% cover with two different amounts of spores in
solution corresponding to approximately 5Ă—106 spores/l and 10Ă—106 spores/l. 31 stumps
received mechanical part cover with the highest spore concentrations of Phlebiopsis gigantea, i.e. approximately 20Ă—106 spores/l. Mechanical treatment was assessed for satisfactory treatment effect. Three months later, samples were collected and analyzed.
There was a significant reduction in frequency and relative areas of Heterobasidion spp.
infections on stumps with manual application of control agents compared to untreated stumps. On average 10 to 23% of stumps subjected to manual treatments were infected compared to 52% for the untreated stumps. However, none of the concentration solutions of Rotstop® and RotstopS differed from the others in reduction of Heterobasidion spp. infections. Mechanical treatment failed to control the Heterobasidion spp. infections, but there was a tendency for the 85.1-95.0% cover class to provide better result than the others. Thus, despite of the incomplete control of the pathogen, stump treatment with different concentrations of Phlebiopsis gigantea oidia in suspensions provided equal effects at the present spore loads of Heterobasidion spp.Effektiviteten av behandling med två pergamentsvampsbaserade (Phlebiopsis gigantea)
lösningar (Rotstop® och RotstopS) i olika koncentrationer mot sporinfektioner av rotticka
(Heterobasidion spp.) på gallringsstubbar av gran (Picea abies) i södra Sverige jämfördes.
Träd avverkades på tre olika lokaler under sommaren 2004 och sammanlagt 285 stubbar
behandlades manuellt med en hundraprocentig täckning i två olika koncentrationer
motsvarande ungefär 5×106 sporer/l respektive 10×106 sporer/l lösning. 31 stubbar på en av
lokalerna behandlades maskinellt med en ofullständig täckning men med den högsta
koncentrationen av pergamentsvamp (RotstopS), ca 20×106 sporer/l lösning. Effekten av den
mekaniska behandlingens partiella täckning jämfördes med den manuella fullständiga. Tre
månader efter behandlingen samlades prover in för analys med avseende på förekomsten av
rotticka.
Alla manuella behandlingar gav en signifikant reducering av frekvensen av och relativa arean
av rottickeinfektioner jämfört med obehandlade stubbar. I genomsnitt var 10 till 23 % av de
manuellt behandlade stubbarna infekterade jämfört med 52 % av de obehandlade. Ingen av de
manuella applikationerna skiljde sig dock frĂĄn varandra. Den mekaniska behandlingen gav
inte ett tillfredsställande resultat men det fanns en tendens till att täckningsgradsklass 85,1-
95,0 % fungerade bättre än de andra. Således, trots att ingen behandling gav en 100 % -ig
minskning av antalet rottickeinfektioner, verkar olika koncentrationer av Rotstop® och
RotstopS ge ett likvärdigt resultat under de förhållanden i sportryck som rådde vid
behandlingen
N-mixture models provide informative crocodile (Crocodylus moreletii) abundance estimates in dynamic environments
Estimates of animal abundance provide essential information for population
ecological studies. However, the recording of individuals in the field can be
challenging, and accurate estimates require analytical techniques which account for
imperfect detection. Here, we quantify local abundances and overall population
size of Morelet’s crocodiles (Crocodylus moreletii) in the region of Calakmul
(Campeche, Mexico), comparing traditional approaches for crocodylians (Minimum
Population Size—MPS; King’s Visible Fraction Method—VFM) with binomial
N-mixture models based on Poisson, zero-inflated Poisson (ZIP) and negative
binomial (NB) distributions. A total of 191 nocturnal spotlight surveys were
conducted across 40 representative locations (hydrologically highly dynamic
aquatic sites locally known as aguadas) over a period of 3 years (2017–2019). Local
abundance estimates revealed a median of 1 both through MPS (min–max: 0–89; first
and third quartiles, Q1–Q3: 0–7) and VFM (0–112; Q1–Q3: 0–9) non-hatchling
C. moreletii for each aguada, respectively. The ZIP based N-mixture approach shown
overall superior confidence over Poisson and NB, and revealed a median of 6 ± 3
individuals (min = 0; max = 120 ± 18; Q1 = 0; Q3 = 18 ± 4) jointly with higher
detectabilities in drying aguadas with low and intermediate vegetation cover.
Extrapolating these inferences across all waterbodies in the study area yielded an
estimated ~10,000 (7,000–11,000) C. moreletii present, highlighting Calakmul as
an important region for this species. Because covariates enable insights into
population responses to local environmental conditions, N-mixture models applied
to spotlight count data result in particularly insightful estimates of crocodylian
detection and abundance
«Smarter Medicine»: 5 Interventionen, die in der ambulanten allgemeinen inneren Medizin vermieden werden sollten
Seit 2012 befasst sich die Schweizerische Gesellschaft für Allgemeine Innere Medizin mit der Problematik der Überdiagnostik und Überversorgung in der Medizin. Nun hat sie beschlossen, eine Liste mit fünf Untersuchungen auf dem Gebiet der ambulanten allgemeinen inneren Medizin zusammenzustellen, die ohne oder mit nur geringem Nutzen bei zahlreichen Patienten durchgeführt werden, gleichzeitig jedoch unerwünschte Nebenwirkungen haben können und zum Anstieg der Gesundheitskosten beitragen
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