26 research outputs found
Ferrets exclusively synthesize Neu5Ac and express naturally humanized influenza A virus receptors
Mammals express the sialic acids N-acetylneuraminic acid (Neu5Ac) and N-glycolylneuraminic acid (Neu5Gc) on cell surfaces, where they act as receptors for pathogens, including influenza A virus (IAV). Neu5Gc is synthesized from Neu5Ac by the enzyme cytidine monophosphate-N-acetylneuraminic acid hydroxylase (CMAH). In humans, this enzyme is inactive and only Neu5Ac is produced. Ferrets are susceptible to human-adapted IAV strains and have been the dominant animal model for IAV studies. Here we show that ferrets, like humans, do not synthesize Neu5Gc. Genomic analysis reveals an ancient, nine-exon deletion in the ferret CMAH gene that is shared by the Pinnipedia and Musteloidia members of the Carnivora. Interactions between two human strains of IAV with the sialyllactose receptor (sialic acid—α2,6Gal) confirm that the type of terminal sialic acid contributes significantly to IAV receptor specificity. Our results indicate that exclusive expression of Neu5Ac contributes to the susceptibility of ferrets to human-adapted IAV strains
Response: Where Might We Find Ecologically Intact Communities?
[Extract] In an attempt to identify areas of the world that represent outstanding examples of ecological integrity, Plumptre et al. (2021) concluded that just 2.8% of Earth's terrestrial area could be considered to qualify. This analysis contrasts with other global assessments that show the extent of areas important for ecological integrity to be at least an order of magnitude higher (Newbold et al., 2016; Watson et al., 2016a; Beyer et al., 2020; Grantham et al., 2020; Hansen et al., 2020; Mokany et al., 2020; Riggio et al., 2020; Williams et al., 2020; De Palma et al., 2021). Plumptre et al. (2021) further argue their methodology and findings can inform Key Biodiversity Area (KBA) delineation
Die Weltwirtschaft im Wandel: Symposium 1975
Seit einigen Jahren verstärkt sich der Eindruck, daß die Weltwirtschaft in einem raschen Wandel begriffen ist. Die Entwicklungsländer fordern eine neue Weltwirtschaftsordnung. Auf die weltweite Hochkonjunktur ist eine scharfe und recht lange anhaltende Rezession gefolgt; aber noch immer dominieren inflationäre Tendenzen. Den Konjunktureinbruch überlagert hat die Vervielfachung des Ölpreises Ende 1973. Sie wurde von vielen Beobachtern als Beginn einer Phase mit zunehmendem Rohstoffmangel und nie gekannten Ungleichgewichten in den Zahlungsbilanzen gedeutet. Von den vielfach geäußerten Befürchtungen haben sich manche als übertrieben erwiesen; denn viele Schwierigkeiten konnte der Markt viel besser als erwartet und ziemlich geräuschlos bewältigen. Gleichwohl erscheint es geraten, die alten und die neuen Probleme der Weltwirtschaft ständig zu beobachten. Vom 23. -27. Juni, traf sich in Kiel eine Gruppe unabhängiger Ökonomen aus Japan, Nordamerika und der Europäischen Gemeinschaft in der Absicht, die Situation der Weltwirtschaft zu analysieren und Vorschläge für wirtschaftspolitische Maßnahmen auf nationaler und internationaler Ebene auszuarbeiten. Das Institut für Weltwirtschaft war Gastgeber. Das Kieler Symposium ist ein Glied in einer Reihe trilateraler Konferenzen über weltwirtschaftliche Fragen, die von der Brookings Institution in Washington, dem Japan Economic Research Center in Tokio und dem Institut für Weltwirtschaft gemeinsam veranstaltet werden. Die Ergebnisse werden jeweils in englischer, japanischer und deutscher Sprache veröffentlicht; frühere Berichte in der deutschen Fassung sind als Kieler Diskussionsbeiträge Nr. 31 "Welthandel und Strukturanpassung in den Industrieländern" und Nr. 36 "Weltrohstoffversorgung: Konflikt oder Kooperation?" erschienen. --
Prescribed Burns in Heathy Swamps Favour Establishment of Threatened Flora
Long fire-free periods cause heathy swamps to transition into late-successional age classes which are characterised by low species richness and a depauperate understorey. The majority of the critically endangered heathy swamps on the Fleurieu Peninsula are long unburnt and lack ‘disturbance dependent’ flora, prompting programs to burn some of the long unburnt vegetation. This thesis investigates the utility of fire as a management tool in heathy swamps. I first assessed the influence of heat and smoke on ex situ seedling emergence from soil samples. Then, I investigated the seed dormancy mechanisms of a critically endangered species in response to fire cues. Lastly, I conducted experimental burns to evaluate in situ plant recovery as a result of fire seasonality and herbivory.
Seedling emergence from the soil samples indicated that fire facilitates the regeneration of threatened ground-stratum natives, including promoting seedling emergence, suppressing competition from dominant species, and providing these threatened ground-stratum natives with opportunities to replenish their seedbanks. Of particular importance, seedling emergence of native shrubs and subshrubs more than doubled with the fire treatment, including the critically endangered Hibbertia tenuis which increased 18-fold. By investigating the dormancy mechanisms of H. tenuis I then found that germination was negligible without smoke. Prescribed burns were then employed, which initiated a transient successional period with reduced overstorey cover, promotion of the understorey, and increased species richness (7.4 vs 4.5 species m-2 in unburnt controls). Within the long-unburnt heathy swamps, 29 % of plant species appearing after burning were absent from the above ground biomass. These plants depend on fire to re-appear above ground, grow, reproduce and replenish their propagule reserves. Populations of H. tenuis were declining in the absence of fire and were restricted to a population of 20 plants but have increased to nearly 600 plants since the experimental burns.
The decline of many Fleurieu Peninsula swamp species can be attributed to an imbalance of age classes in the landscape, given that approximately 98 % of the swamps are likely in late-successional stages. With infrequent burning, native ferns and taller shrubs outcompete threatened ground-stratum plant species. I argue that for fire-dependent species, such as H. tenuis, local extinctions will occur if the time between fires is greater than the lifespan of the species in both the above- and below-ground vegetation. However, despite potential benefits of prescribed burns, herbivory and fire seasonality can have negative implications for recovery. Herbivory negatively impacts recovery after fire by excluding 12 % of species and slowing the recovery of many others. Native species also had opposing seasonal fire preferences, such that fire in any given season may benefit one species to the detriment of another. In heathy swamps, this thesis supports the utility of prescribed burns for maintaining a balanced spectrum of age classes, but also highlights the importance of mitigating herbivory and considering the effects of fire seasonality.Thesis (Ph.D.) -- University of Adelaide, School of Biological Sciences, 202
Retention and restoration priorities for climate adaptation in a multi-use landscape
Retaining and restoring habitat in areas that will remain climatically suitable through time is a key strategy for helping species' adapt to climate change - particularly in multi-use landscapes where species' find it difficult to track suitable climates. We advance on existing climate-smart conservation planning studies to identify retention and restoration priorities for potential climate change refugia sites in a vast multi-use landscape. We illustrate our approach for Australia's Great Dividing Range (GDR), where the entire habitat of 26 vertebrate species – including 11 endemics – will be climatically unsuitable by the year 2085 under a high emissions scenario. We developed two planning scenarios to secure areas that will remain climatically suitable for an additional 1036 vertebrate species in the GDR – a scenario that permits both the retention of high quality habitat and the restoration of land currently used for forestry or agriculture (i.e. ‘balanced’)and a scenario that favours the retention of high quality habitat above land restoration efforts (i.e. ‘retention-focused’). For both planning scenarios, we identified priority conservation areas that will complement existing protected areas in the GDR and then compared ecological trade-offs associated with adopting a balanced or retention-focused approach to conservation. We found that a retention-focused approach would deliver equivalent ecological benefits for most species, and enhanced conservation of climatically suitable area for 95 other species, when compared to a balanced planning approach. Under a balanced planning approach, seventy-four percent of high priority conservation area (49,650 km )would overlap with forestry or agricultural land-uses, and hence will require extensive restoration efforts to serve as habitat for climate-imperilled species. However, we found that at least 270 species in the GDR rely heavily on ecological restoration of agricultural lands to persist under climate change. Our study provides immediate guidance for on-ground management actions, and provides a robust methodology that can support climate change adaptation decisions in multi-use landscapes around the world
How to send a finch extinct
Australia's high species extinction rate shows no sign of abating, with at least three vertebrate extinctions recorded within the last decade. In each case, scientists have published ‘post-mortems’ examining the context of these recent extinctions. By tracing the decline of a once-widespread and common bird to the point that it has disappeared from over 80% of its original range, and describing the circumstances under which habitat loss continues to be approved despite its formal protection, we present a ‘pre-mortem’ for the endangered, and endemic, southern black-throated finch (Poephila cincta cincta). The southern black-throated finch has suffered extensive habitat loss historically, much of which was unregulated. In 2000, Australia increased environmental regulation, and the southern black-throated finch was listed under the Commonwealth's Environment Protection & Biodiversity Conservation Act. Despite the increased environmental regulation and formal protection, habitat loss for the southern black-throated finch has continued, mostly incrementally but resulting in large cumulative loss. In the face of steep population decline and range contraction of BTF, five large coal mines were approved between 2012 and 2015 by both State and Commonwealth governments that will remove most of the largest area of high quality habitat that remains. We outline the policy settings under which the decline occurred, with a particular focus on recent ongoing habitat loss occurring within a highly regulated environment. We show that despite Australia's comparatively strong governance and regulatory frameworks, legally permitted habitat loss continues even for imperilled taxa formally listed under State and Commonwealth environment protection laws
Neuromuscular adapatations to traditional versus eccentric-overload resistance training
Eccentric actions are thought to be particularly important to increase muscle strength and size but are often performed at submaximal intensities during traditional resistance training. The aim of the present study was to compare neuromuscular adaptations from eccentric-overload resistance training (EO) to traditional resistance training (TRT)
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Use of bicyclic esters or amides for the treatment of diseases responsive to enhanced potassium channel activity
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Un approccio stocastico-simulativo per le scelte di finanziamento con applicazione
In questo lavoro si analizza la situazione di una delle imprese turistico-alberghiere più importanti del lido di Sottomarina di Chioggia relativamente alla decisione da parte della Proprietà di effettuare un cospicuo investimento nella struttura ricettiva, o di cedere la struttura medesima. Questa decisione dovrà basarsi sulla valutazione di alcune importanti questioni: dapprima si dovranno valutare le prospettive economiche future del settore turistico di Sottomarina, cercando di capire se sussistono i presupposti per una riqualificazione regionale e nazionale del turismo balneare; poi si dovrà verificare se la struttura economico-aziendale dell’impresa potrà sopportare il peso di un finanziamento, stimato in circa 4 miliardi di lire italiane, necessario per la realizzazione dei lavori di riammodernamento della struttura. Proprio quest’ultima valutazione costituirà il centro tematico di questa trattazione: mediante l’applicazione di un modello stocastico-simulativo opportunamente sviluppato verranno effettuate una serie di simulazioni fina-lizzate a fornire una base su cui poter effettuare la valutazione e, quindi, scegliere se continuare nell’attività, o se cedere definitivamente l’impresa
Lots of loss with little scrutiny: the attrition of habitat critical for threatened species in Australia
Australia has one of the worst extinction rates of any nation, yet there has been little assessment of the effect of its flagship environmental legislation, the Environment Protection and Biodiversity Conservation Act 1999 (EPBC Act), to prevent species extinction. By coupling remotely sensed forest and woodland data with the distributions of 1,638 terrestrial threatened species, terrestrial migratory species, and threatened ecological communities, we quantified the loss of potential habitat and communities since the EPBC Act came into force in 2000. We found that over 7.7 million ha of potential habitat and communities were cleared in the period 2000–2017. Of this clearing, over 93% was not referred to the Federal Government for assessment, meaning the loss was not scrutinized under the EPBC Act. While 1,390 (84%) species suffered loss, Mount Cooper striped skink, Keighery's macarthuria, and Southern black‐throated finch lost 25, 23, and 10% of potential habitat, respectively. Iconic Australian species, such as koala, also lost ~1 million ha (2.3%) of potential habitat. Our analysis showed that the EPBC Act is ineffective at protecting potential habitat for terrestrial threatened species, terrestrial migratory species, or threatened ecological communities. We recommend that when scientifically determinable, critical habitat is demarcated for listed species and communities, which provides absolute protection that is enforced, monitored, and investigated by the regulator. Without a fundamental change in how environmental law is enforced, Australia faces an increasing extinction rate