108 research outputs found
Long-term effects of supplementary feeding of moose on browsing impact at a landscape scale
This is the author's version before it was send to the publisher. Therefore it can differ slightly from the published version. For the published version, please go to: http://www.sciencedirect.com/science/article/pii/S0378112713007925Supplementary feeding of wildlife is a common management practice, increasingly used to
reduce or divert herbivore impact from sensitive habitats, forestry or agriculture. The
landscape-scale spatial distribution of herbivory in relation to supplementary or diversionary
feeding stations is of particular relevance to wildlife and land management, yet has never been
quantified. We considered multiple hypotheses, based on central-place foraging theory, to
investigate how landscape-scale browsing impact changed as a function of distance from
feeding stations and thereby test the effectiveness of diversionary feeding. We assessed the
landscape-scale browsing impact of moose by quantifying browsing patterns and moose
density in commercially-valuable young Scots pine stands in an area of south-east Norway
with a long history of winter feeding. We also used positions from GPS-collared female
moose to investigate the spatial distribution of individuals across the landscape. Moose
density and browsing impact at a fine spatial scale (<1km) followed an exponential decrease
with distance from diversionary feeding stations. However, at a landscape scale (1-10 km),
browsing impact did not show any relationship with distance to feeding stations. Leader stem
browsing on Scots pine trees was high at both the local (< 1 km; 68 ± 12 %) and landscape (1-
10 km; 56 ± 7 %) scales. In addition, browsing on commercially valuable Norway spruce,
which is normally avoided by moose, was locally high around feeding stations. As currently
practiced, long-term diversionary feeding of moose was ineffective in diverting browsing
impact from young pine stands at the landscape scale. Browsing on commercially-important
tree species was sufficiently high that economic consequences could be expected. To avoid
further conflict, we suggest a combination of reducing the moose density and increasing the
availability of natural or more attractive supplementary forage
The helminth product, ES-62, protects against airway inflammation by resetting the Th cell phenotype
We previously demonstrated inhibition of ovalbumin (OVA)-induced allergic airway hyper-responsiveness in the mouse using ES-62, a phosphorylcholine-containing glycoprotein secreted by the filarial nematode, Acanthocheilonema viteae. This inhibition correlated with ES-62-induced mast cell desensitisation, although the degree to which this reflected direct targeting of mast cells remained unclear as suppression of the Th2 phenotype of the inflammatory response, as measured by eosinophilia and IL-4 levels in the lungs, was also observed. We now show that inhibition of the lung Th2 phenotype is reflected in ex vivo analyses of draining lymph node recall cultures and accompanied by a decrease in the serum levels of total and OVA-specific IgE. Moreover, ES-62 also suppresses the lung infiltration by neutrophils that is associated with severe asthma and is generally refractory to conventional anti-inflammatory therapies, including steroids. Protection against Th2-associated airway inflammation does not reflect induction of regulatory T cell (Treg) responses (there is no increased IL-10 or Foxp3 expression) but rather a switch in polarisation towards increased T-bet expression and IFNγ production. This ES-62-driven switch in the Th1/Th2 balance is accompanied by decreased IL-17 responses, a finding in line with reports that IFNγ and IL-17 are counter-regulatory. Consistent with ES-62 mediating its effects via IFNγ-mediated suppression of pathogenic Th2/Th17 responses, we found that neutralising anti-IFNγ antibodies blocked protection against airway inflammation in terms of pro-inflammatory cell infiltration, particularly by neutrophils and lung pathology. Collectively, these studies indicate that ES-62, or more likely small molecule analogues, could have therapeutic potential in asthma, in particular for those subtypes of patients (e.g. smokers, steroid-resistant) who are refractory to current treatments
The efficacy of whole human genome capture on ancient dental calculus and dentin
Objectives: Dental calculus is among the richest known sources of ancient DNA in the archaeological record. Although most DNA within calculus is microbial, it has been shown to contain sufficient human DNA for the targeted retrieval of whole mitochondrial genomes. Here, we explore whether calculus is also a viable substrate for whole human genome recovery using targeted enrichment techniques. Materials and methods: Total DNA extracted from 24 paired archaeological human dentin and calculus samples was subjected to whole human genome enrichment using in-solution hybridization capture and high-throughput sequencing. Results: Total DNA from calculus exceeded that of dentin in all cases, and although the proportion of human DNA was generally lower in calculus, the absolute human DNA content of calculus and dentin was not significantly different. Whole genome enrichment resulted in up to fourfold enrichment of the human endogenous DNA content for both dentin and dental calculus libraries, albeit with some loss in complexity. Recovering more on-target reads for the same sequencing effort generally improved the quality of downstream analyses, such as sex and ancestry estimation. For nonhuman DNA, comparison of phylum-level microbial community structure revealed few differences between precapture and postcapture libraries, indicating that off-target sequences in human genome-enriched calculus libraries may still be useful for oral microbiome reconstruction. Discussion: While ancient human dental calculus does contain endogenous human DNA sequences, their relative proportion is low when compared with other skeletal tissues. Whole genome enrichment can help increase the proportion of recovered human reads, but in this instance enrichment efficiency was relatively low when compared with other forms of capture. We conclude that further optimization is necessary before the method can be routinely applied to archaeological samples
The marine isotope stage 1–5 cryptotephra record of Tenaghi Philippon, Greece:Towards a detailed tephrostratigraphic framework for the Eastern Mediterranean region
The iconic climate archive of Tenaghi Philippon (TP), NE Greece, allows the study of short-term palaeoclimatic and environmental change throughout the past 1.3 Ma. To provide high-quality age control for detailed palaeoclimate reconstructions based on the TP archive, (crypto)tephra studies of a peat core ‘TP-2005’ have been carried out for the 0–130 ka interval. The results show that the TP basin is ideally positioned to receive tephra fall from both the Italian and Aegean Arc volcanic provinces. Two visible tephra layers, the Santorini Cape Riva/Y-2 (c. 22 ka) and the Campanian Ignimbrite (CI)/Y-5 (c. 39.8 ka) tephras, and six primary cryptotephra layers, namely the early Holocene E1 tephra from the Aeolian Islands (c. 8.3 ka), the Campanian Y-3 (c. 29 ka) and X-6 tephras (c. 109.5 ka), as well as counterpart tephras TM-18-1d (c. 40.4 ka), TM-23-11 (c. 92.4 ka) and TM-33-1a (c. 116.7 ka) from the Lago Grande di Monticchio sequence (southern Italy), were identified along with repeatedly redeposited Y-2 and CI tephra material. Bayesian modelling of the ages of seven of the primary tephra layers, 60 radiocarbon measurements and 20 palynological control points have been applied to markedly improve the chronology of the TP archive. This revised chronology constrains the age of tephra TM-18-1d to 40.90–41.66 cal ka BP (95.4% range). Several tephra layers identified in the TP record form important isochrons for correlating this archive with other terrestrial (e.g., Lago Grande di Monticchio, Sulmona Basin and Lake Ohrid) and marine (e.g., Adriatic Sea core PRAD 1-2 and Aegean Sea core LC21) palaeoclimate records in the Mediterranean region
Platformed antagonism: Racist discourses on fake Muslim Facebook pages
This research examines how fake identities on social media create
and sustain antagonistic and racist discourses. It does so by
analysing 11 Danish Facebook pages, disguised as Muslim
extremists living in Denmark, conspiring to kill and rape Danish
citizens. It explores how anonymous content producers utilise
Facebook’s socio-technical characteristics to construct, what we
propose to term as, platformed antagonism. This term refers to
socio-technical and discursive practices that produce new modes
of antagonistic relations on social media platforms. Through a
discourse-theoretical analysis of posts, images, ‘about’ sections
and user comments on the studied Facebook pages, the article
highlights how antagonism between ethno-cultural identities is
produced on social media through fictitious social media
accounts, prompting thousands of user reactions. These findings
enhance our current understanding of how antagonism and
racism are constructed and amplified within social media
environments
Preferências domésticas e instituições do processo decisório em política econômica externa
Building robust, practicable counterfactuals and scenarios to evaluate the impact of species conservation interventions using inferential approaches
Robust evaluation of the impact of biodiversity conservation actions is important not only for ensuring that conservation strategies are effective and maximise return on investment, but also to identify and celebrate successful conservation strategies. This evaluation can be retrospective (comparing the current situation to a counterfactual scenario) or forward-looking (comparing future scenarios with or without conservation). However, assessment of impact using experimental or quasi-experimental designs is typically difficult in conservation, so rigorous inferential approaches are required. Inferential assessment of impact is a key part of the new IUCN Green Status of Species, which greatly amplifies the need for standardised and practical species impact evaluation methods. Here, we use the Green Status of Species method as a base to review how inferential methods can be used to evaluate conservation impact at the species level. We identify three key components of the inferential impact evaluation process—estimation of scenario outcomes, selection of baseline scenario, and frame of reference—and explain, with examples, how to reduce the subjectivity of these steps. We propose a step-by-step guide, incorporating these principles, that can be used to infer scenario outcomes in order to evaluate past and future conservation impact in a wide range of situations, not just Green Status of Species assessments. We recommend that future non-experimental conservation interventions facilitate the process of evaluating impact by identifying the variable(s) that will be used to measure impact at the design stage, and by using conceptual models to help choose conservation actions most likely to have the desired impact
Woodland Recovery after Suppression of Deer: Cascade effects for Small Mammals, Wood Mice (Apodemus sylvaticus) and Bank Voles (Myodes glareolus)
Over the past century, increases in both density and distribution of deer species in the Northern Hemisphere have resulted in major changes in ground flora and undergrowth vegetation of woodland habitats, and consequentially the animal communities that inhabit them. In this study, we tested whether recovery in the vegetative habitat of a woodland due to effective deer management (from a peak of 0.4–1.5 to <0.17 deer per ha) had translated to the small mammal community as an example of a higher order cascade effect. We compared deer-free exclosures with neighboring open woodland using capture-mark-recapture (CMR) methods to see if the significant difference in bank vole (Myodes glareolus) and wood mouse (Apodemus sylvaticus) numbers between these environments from 2001–2003 persisted in 2010. Using the multi-state Robust Design method in program MARK we found survival and abundance of both voles and mice to be equivalent between the open woodland and the experimental exclosures with no differences in various metrics of population structure (age structure, sex composition, reproductive activity) and individual fitness (weight), although the vole population showed variation both locally and temporally. This suggests that the vegetative habitat - having passed some threshold of complexity due to lowered deer density - has allowed recovery of the small mammal community, although patch dynamics associated with vegetation complexity still remain. We conclude that the response of small mammal communities to environmental disturbance such as intense browsing pressure can be rapidly reversed once the disturbing agent has been removed and the vegetative habitat is allowed to increase in density and complexity, although we encourage caution, as a source/sink dynamic may emerge between old growth patches and the recently disturbed habitat under harsh conditions
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