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When is a native species invasive? Incursion of a novel predatory marsupial detected using molecular and historical data 下载免费PDF全文
Catriona D. Campbell Stephen D. Sarre Dejan Stojanovic Bernd Gruber Kathryn Medlock Stephen Harris Anna J. MacDonald Clare E. Holleley 《Diversity & distributions》2018,24(6):831-840
Aim
Range expansions facilitated by humans or in response to local biotic or abiotic stressors provide the opportunity for species to occupy novel environments. Classifying the status of newly expanded populations can be difficult, particularly when the timing and nature of the range expansion are unclear. Should native species in new habitats be considered invasive pests or actively conserved? Here, we present an analytical framework applied to an Australian marsupial, the sugar glider (Petaurus breviceps), a species that preys upon on an endangered parrot in Tasmania, and whose provenance was uncertain.Location
Tasmania, Australia.Methods
We conducted an extensive search of historical records for sugar glider occurrences in Tasmania. Source material included museum collection data, early European expedition logs, community observation records, and peer‐reviewed and grey literature. To determine the provenance of the Tasmanian population, we sequenced two mitochondrial genes and one nuclear gene in Tasmanian animals (n = 27) and in individuals across the species' native range. We then estimated divergence times between Tasmania and southern Australian populations using phylogenetic and Bayesian analyses.Results
We found no historical evidence of sugar gliders occurring in Tasmania prior to 1835. All Tasmanian individuals (n = 27) were genetically identical at the three genes surveyed here with those individuals being 0.125% divergent from individuals from a population in Victoria. Bayesian analysis of divergence between Tasmanian individuals and southern Australian individuals suggested a recent introduction of sugar gliders into Tasmania from southern Australia.Main conclusions
Molecular and historical data demonstrate that Tasmanian sugar gliders are a recent, post‐European, anthropogenic introduction from mainland Victoria. This result has implications for the management of the species in relation to their impact on an endangered parrot. The analytical framework outlined here can assist environmental managers with the complex task of assessing the status of recently expanded or introduced native species.33.
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Milica D olovi GM Jankovi RB olovi Vesna M Martinovi-emeriki 《Cancer immunology, immunotherapy : CII》1998,15(4):286-288
A case of primary nonsecretory plasmacytoma of the spleen is reported. On laparotomy and splenectomy a 920 g spleen was removed,
measuring 16×14×6 cm. The cut surface of the entire spleen showed that the tumour occupied most of the splenic tissue. A bone
marrow aspirate and trephine, skeletal survey showed no signs of myeloma. Biopsy of the liver and regional lymph nodes was
normal. Immunocytochemistry of the splenic tumour showed positivity for pan-B and plasma cell markers. After splenectomy the
patient was treated with chemotherapy according to protocol VBCMP (M2). 相似文献
35.
Momir M. Paunovic Dunja G. Jakovcev-Todorovic Vladica M. Simic Bojana D. Stojanovic Predrag D. Cakic 《Biologia》2007,62(2):214-221
Results of the investigation of the aquatic macroinvertebrate fauna along a 504 km stretch of the Danube River in Serbia are
presented. A total of 74 macroinvertebrate taxa were observed during a 2001 survey. Oligochaeta and Mollusca were the principal
components of the community with regard to species richness and abundance. Based on data on the qualitative composition of
the macroinvertebrate fauna, a correspondence analysis divided the investigated stretch in three sectors — upper (Pannonian),
Iron Gate sector and entrance sector to the Iron Gate stretch. The distribution patterns of certain species supported the
division of sectors defined by correspondence analysis. 相似文献
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The synthesis of a series of lanthanide tetracyanoplatinates containing the auxiliary ligands 1,10′-phenanthroline (phen) or 2,2′-bipyridine (bpy) have been carried out by reaction of Ln3+ nitrate salts with phen or bpy and potassium tetracyanoplatinate in solvent systems containing dimethylsulfoxide and dimethylformamide. The use of these solvents has lead to the isolation of [{Ln(DMSO)2(C12H8N2)(H2O)3}2Pt(CN)4](Pt(CN)4)2·2C12H8N2·4H2O (Ln = Eu (Eu-1), Tb (Tb-1), Yb(Yb-1)), [Ln(DMF)3(C12H8N2)(H2O)2NO3]Pt(CN)4 (Ln = La (La-2), Eu (Eu-2), Tb (Tb-2)), and [Ln(DMF)3(C10H8N2)(H2O)2NO3]Pt(CN)4 (Ln = La (La-3), Sm (Sm-3), Eu (Eu-3), Tb (Tb-3)) in the form of single crystals. Single-crystal X-ray diffraction has been used to investigate their structural features. The use of DMSO versus DMF as the solvent results in markedly different structural features. Eu-1 contains [{Eu(DMSO)2(C12H8N2)(H2O)3}2Pt(CN)4]2+ complex cations where the two Eu3+ centers are linked by a trans-bridging Pt(CN)42− anion to form a dimeric lanthanide complex cation. An additional uncoordinated Pt(CN)42− anion balances charge. Eu-2 and Eu-3 consist of zero-dimensional salts with [Eu(DMF)3(C12H8N2)(H2O)2(NO3)]2+ or [Eu(DMF)3(C10H8N2)(H2O)2(NO3)]2+ complex cations, respectively, and only non-coordinated Pt(CN)42− anions. Photoluminescence measurements illustrate that the Eu3+ and Tb3+ compounds for all three structure types display enhanced emission due to intramolecular energy transfer from the coordinated cyclic amines. 相似文献
39.
Milorad Stojanovic 《Inorganica chimica acta》2011,376(1):414-421
The synthesis of a number of lanthanide tetracyanometallate (TCM) compounds have been carried out by reaction of Ln3+ nitrate salts and potassium tetracyanometallates in solvent systems containing dimethylsulfoxide and water. These reactions result in the isolation of three distinct structure types: (1) monoclinic [Ln(DMSO)4(H2O)3M(CN)4](M(CN)4)0.5·2H2O (Ln = Eu, Tb and M = Pd, Pt), (2) orthorhombic {La(DMSO)3(H2O)2(NO3)M(CN)4}∞·H2O (M = Pd, Pt), and (3) orthorhombic {Ln(DMSO)3(H2O)(NO3)M(CN)4}∞ (Ln = Tb and M = Pd, Pt; Ln = Er, Yb and M = Pt) in the form of single crystals. Single-crystal X-ray diffraction has been used to investigate their structural features. Structure type 1 is a zero dimensional ionic compound with a M/Ln ratio of 1.5:1. It contains coordinated as well as uncoordinated [M(CN)4]2− (M = Pd, Pt) anions and features relatively long platinophilic interactions. Structure types 2 and 3 differ quite drastically from structure type 1, but they are very similar to each other. Both of the latter are one-dimensional in nature due to chains containing linkage of Ln3+ coordination spheres with trans-bridging [M(CN)4]2− anions. These coordination polymers both have a M/Ln ratio of 1:1, a lack of platinophilic interactions, and incorporation of a bidentate NO3− for charge balance. Photoluminescence properties for select Eu3+ and Tb3+ compounds have been investigated. They show characteristic absorption and emission for the Ln3+ ions, but no significant influence of the tetracyanometallate anions. 相似文献
40.
Barbara WollerSusan Luiskandl Milica PopovicBarbara E.M. Prieler Gloria IkongeMichaela Mutzl Holger RehmannRuth Herbst 《Biochimica et Biophysica Acta (BBA)/Molecular Cell Research》2011,1813(6):1198-1210
RIN proteins serve as guanine nucleotide exchange factors for Rab5a. They are characterized by the presence of a RIN homology domain and a C-terminal Vps9 domain. Currently three family members have been described and analyzed. Here we report the identification of a novel RIN family member, Rin-like (Rinl), that represents a new interaction partner of the receptor tyrosine kinase MuSK, which is an essential key regulator of neuromuscular synapse development. Rinl is localized to neuromuscular synapses but shows the highest expression in thymus and spleen. Rinl preferentially binds to nucleotide-free Rab5a and catalyzes the exchange of GDP for GTP. Moreover, Rinl also binds GDP-bound Rab22 and increases the GDP/GTP exchange implicating Rinl in endocytotic processes regulated by Rab5a and Rab22. Interestingly, Rinl shows a higher catalytic rate for Rab22 compared to Rab5a. Rinl is closely associated with the cytoskeleton and thus contributes to the spatial control of Rab5a and Rab22 signaling at actin-positive compartments. Most importantly, overexpression of Rinl affects fluid-phase as well as EGFR endocytosis. 相似文献