10 research outputs found
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Flowers of Deceptive Aristolochia microstoma Are Pollinated by Phorid Flies and Emit Volatiles Known From Invertebrate Carrion
Deceptive flowers decoy pollinators by advertising a reward, which finally is not provided. Numerous deceptive plants are pollinated by Diptera, but the attractive cues and deceptive strategies are only identified in a few cases. A typical fly-deceptive plant genus is Aristolochia, which evolved sophisticated trap flowers to temporarily capture pollinators. Though rarely demonstrated by experimental approaches, Aristolochia species are believed to chemically mimic brood sites, food sources for adult flies, or utilize sexual deception. Indeed, for most species, studies on scent composition and attractive signals are lacking. In this study, we focused on Aristolochia microstoma, a peculiar Greek endemic with flowers that are presented at ground level in the leaf litter or between rocks and are characterized by a unique morphology. We analyzed flower visitor and pollinator spectra and identified the floral scent composition using dynamic headspace and gas chromatography coupled to mass spectrometry (GC/MS). Female and male phorid flies (Phoridae) are the exclusive pollinators, although the flowers are also frequently visited by Sciaridae, as well as typical ground-dwelling arthropods, such as Collembola and arachnids. The carrion-like floral scent mainly consists of the oligosulphide dimethyldisulfide and the nitrogen-bearing compound 2,5-dimethylpyrazine. These compounds together are known to be released from decomposing insects, and thus, we conclude that pollinators are likely deceived by chemical imitation of invertebrate carrion, a deceptive strategy not described from another plant species so far.</jats:p
Using the IUCN Environmental Impact Classification for Alien Taxa to inform decision-making
The Environmental Impact Classification for Alien Taxa (EICAT) is an important tool for biological invasion policy and management and has been adopted as an International Union for Conservation of Nature (IUCN) standard to measure the severity of environmental impacts caused by organisms living outside their native ranges. EICAT has already been incorporated into some national and local decision-making procedures, making it a particularly relevant resource for addressing the impact of non-native species. Recently, some of the underlying conceptual principles of EICAT, particularly those related to the use of the precautionary approach, have been challenged. Although still relatively new, guidelines for the application and interpretation of EICAT will be periodically revisited by the IUCN community, based on scientific evidence, to improve the process. Some of the criticisms recently raised are based on subjectively selected assumptions that cannot be generalized and may harm global efforts to manage biological invasions. EICAT adopts a precautionary principle by considering a speciesâ impact history elsewhere because some taxa have traits that can make them inherently more harmful. Furthermore, non-native species are often important drivers of biodiversity loss even in the presence of other pressures. Ignoring the precautionary principle when tackling the impacts of non-native species has led to devastating consequences for human well-being, biodiversity, and ecosystems, as well as poor management outcomes, and thus to significant economic costs. EICAT is a relevant tool because it supports prioritization and management of non-native species and meeting and monitoring progress toward the KunmingâMontreal Global Biodiversity Framework (GBF) Target 6
Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences
The question whether taxonomic descriptions naming new animal species without type specimen(s) deposited in collections should be accepted for publication by scientific journals and allowed by the Code has already been discussed in Zootaxa (Dubois & NemĂ©sio 2007; Donegan 2008, 2009; NemĂ©sio 2009aâb; Dubois 2009; Gentile & Snell 2009; Minelli 2009; Cianferoni & Bartolozzi 2016; Amorim et al. 2016). This question was again raised in a letter supported
by 35 signatories published in the journal Nature (Pape et al. 2016) on 15 September 2016. On 25 September 2016, the following rebuttal (strictly limited to 300 words as per the editorial rules of Nature) was submitted to Nature, which on
18 October 2016 refused to publish it. As we think this problem is a very important one for zoological taxonomy, this text is published here exactly as submitted to Nature, followed by the list of the 493 taxonomists and collection-based
researchers who signed it in the short time span from 20 September to 6 October 2016
Reconstruction of the Distal Radius following Tumour Resection Using an Osteoarticular Allograft
Reconstruction of the distal radius following tumour resection is challenging and various techniques are recorded. We retrospectively analysed the outcome of five patients (one male and four females) after reconstruction of the distal radius with osteoarticular allograft, following tumour resection. Mean followup was 32 months (range, 4â121). In three of the five patients the dominant limb was affected. Mean bone resection length was 6.5 centimetres (range, 5â11.5). Two grafts developed nonunion, both successfully treated with autologous bone grafting. No infection, graft fracture, or failure occurred. Mean flexion/extension was 38/60 degrees and mean pronation/supination was 77/77 degrees. The mean Mayo wrist score was 84 and the mean DASH score was 8, both representing a good functional result. Therefore we state the notion that osteoarticular allograft reconstruction of distal radius provides good to excellent functional results
Three Metachronous Osteosarcomas within 22 Years without Pulmonary Metastases: A Case Report and Review of the Literature
Introduction. We present the extremely rare case of a patient with three metachronous osteosarcomas within 22 years without evident pulmonary manifestation of disease 30 years after first diagnosis. Case Presentation. In 1983, a high-grade osteosarcoma of the left distal femur was diagnosed in an 18-year-old Caucasian male. He received rotationplasty accompanied by pre- and postoperative chemotherapy. Ten years later, an osteoblastic osteosarcoma occurred in TH12. En bloc resection and pre- and postoperative chemotherapy followed. In 2005, the patient developed another high-grade osteosarcoma in his right distal femur. Treatment included a wide resection and reconstruction with a tumour endoprosthesis as well as (neo)adjuvant chemotherapy. After the third tumour occurrence, cytogenetic and molecular genetic examinations (p53, rb1) were performed, showing a normal genetic pattern. Screening for metastases never showed clinical evidence of extraskeletal tumour manifestation. Discussion. In patients presenting metachronous osteosarcoma, identification of their lesions clonality (second primary tumour or metastases) could lead to a better understanding of tumour development and help to filter patients who need extended long-term followup due to a higher risk of late occurring sarcoma recurrence
The Vienna Genesis: An Example of Late Antique Purple Parchment
The investigation and conservation of the Vienna Genesis, a Late Antique manuscript on purple parchment, included the study of parchment production and purple dyeing in the sixth century. The process of parchment making and of purple dyeing was recreated and compared with the Vienna Genesis and other manuscripts from the sixth and eighth centuries. Parchment made from the hides of young lambs and dyed with orchil resembled the folios of the Vienna Genesis. The results of material analysis and the study of parchment technology influenced decisions for the conservation and storage of the manuscript. Fragile areas of ink and parchment were stabilised with strips of adhesive coated Japanese tissue paper. The single folios are stored in folders of Japanese paper and museum matboard within a sink mat
Tick-Borne Encephalitis Specific Lymphocyte Response after Allogeneic Hematopoietic Stem Cell Transplantation Predicts Humoral Immunity after Vaccination
The aim of this prospective study was to assess lymphocyte proliferative and cytokine response prior to and following tick-borne encephalitis (TBE) immunization among patients after allogeneic hematopoietic stem cell transplantation (HSCT). Seventeen adult patients 11â13 months after HSCT and eight unvaccinated healthy adults received up to three TBE vaccinations. Following in vitro stimulation with TBE-antigen, lymphocyte proliferation and cytokine secretion (IL-2, IL-10, IL-13, TNF-alpha, IFN-gamma, GM-CSF) were analyzed by thymidine incorporation assay and the Luminex system. Ten patients (59%) showed significant baseline TBE-specific lymphocyte proliferation (stimulation index (SI) > 3) prior to vaccination, but none of the unvaccinated controls (p = 0.002). All patients with a TBE-specific antibody response after two vaccinations (at least 2-fold increase of neutralization test titers) exhibited a strong TBE-specific lymphocyte proliferative response at baseline (SI > 10). Patients with sibling donors had a significantly stronger baseline TBE-specific lymphocyte proliferative and IL-13 cytokine response than patients with unrelated donors (p < 0.05). In conclusion, a relevant proportion of patients showed TBE-specific lymphocyte proliferative and cytokine responses prior to vaccination after HSCT, which predicted the humoral response to the vaccine. Patients with vaccinated sibling donors were more likely to elicit a cellular immune response than patients with unrelated donors of unknown vaccination status