36 research outputs found
ALMA observations of 99 GHz free-free and H40 line emission from star formation in the centre of NGC 253
We present Atacama Large Millimeter/submillimeter Array observations of 99.02
GHz free-free and H40 emission from the centre of the nearby starburst
galaxy NGC 253. We calculate electron temperatures of 3700-4500 K for the
photoionized gas, which agrees with previous measurements. We measure a
photoionizing photon production rate of s and
a star formation rate of M yr within the central
2010 arcsec, which fall within the broad range of measurements from
previous millimetre and radio observations but which are better constrained. We
also demonstrate that the dust opacities are ~3 dex higher than inferred from
previous near-infrared data, which illustrates the benefits of using millimetre
star formation tracers in very dusty sources.Comment: 5 pages, 3 figures, accepted for publication in MNRAS Letter
Bacterial membrane vesicles transport their DNA cargo into host cells
© 2017 The Author(s). Bacterial outer membrane vesicles (OMVs) are extracellular sacs containing biologically active products, such as proteins, cell wall components and toxins. OMVs are reported to contain DNA, however, little is known about the nature of this DNA, nor whether it can be transported into host cells. Our work demonstrates that chromosomal DNA is packaged into OMVs shed by bacteria during exponential phase. Most of this DNA was present on the external surfaces of OMVs, with smaller amounts located internally. The DNA within the internal compartments of Pseudomonas aeruginosa OMVs were consistently enriched in specific regions of the bacterial chromosome, encoding proteins involved in virulence, stress response, antibiotic resistance and metabolism. Furthermore, we demonstrated that OMVs carry DNA into eukaryotic cells, and this DNA was detectable by PCR in the nuclear fraction of cells. These findings suggest a role for OMV-associated DNA in bacterial-host cell interactions and have implications for OMV-based vaccines
Creation of forest edges has a global impact on forest vertebrates
Forest edges influence more than half of the world's forests and contribute to worldwide declines in biodiversity and ecosystem functions. However, predicting these declines is challenging in heterogeneous fragmented landscapes. Here we assembled a global dataset on species responses to fragmentation and developed a statistical approach for quantifying edge impacts in heterogeneous landscapes to quantify edge-determined changes in abundance of 1,673 vertebrate species. We show that the abundances of 85% of species are affected, either positively or negatively, by forest edges. Species that live in the centre of the forest (forest core), that were more likely to be listed as threatened by the International Union for Conservation of Nature (IUCN), reached peak abundances only at sites farther than 200-400 m from sharp high-contrast forest edges. Smaller-bodied amphibians, larger reptiles and medium-sized non-volant mammals experienced a larger reduction in suitable habitat than other forest-core species. Our results highlight the pervasive ability of forest edges to restructure ecological communities on a global scale
Recommended from our members
BIOFRAG â a new database for analyzing BIOdiversity responses to forest FRAGmentation
Habitat fragmentation studies have produced complex results that are challenging
to synthesize. Inconsistencies among studies may result from variation in
the choice of landscape metrics and response variables, which is often compounded
by a lack of key statistical or methodological information. Collating
primary datasets on biodiversity responses to fragmentation in a consistent and
flexible database permits simple data retrieval for subsequent analyses. We present
a relational database that links such field data to taxonomic nomenclature,
spatial and temporal plot attributes, and environmental characteristics. Field
assessments include measurements of the response(s) (e.g., presence, abundance,
ground cover) of one or more species linked to plots in fragments
within a partially forested landscape. The database currently holds 9830 unique
species recorded in plots of 58 unique landscapes in six of eight realms: mammals
315, birds 1286, herptiles 460, insects 4521, spiders 204, other arthropods
85, gastropods 70, annelids 8, platyhelminthes 4, Onychophora 2, vascular
plants 2112, nonvascular plants and lichens 320, and fungi 449. Three landscapes
were sampled as long-term time series (>10 years). Seven hundred and
eleven species are found in two or more landscapes. Consolidating the substantial
amount of primary data available on biodiversity responses to fragmentation
in the context of land-use change and natural disturbances is an essential
part of understanding the effects of increasing anthropogenic pressures on land.
The consistent format of this database facilitates testing of generalizations concerning
biologic responses to fragmentation across diverse systems and taxa. It
also allows the re-examination of existing datasets with alternative landscape
metrics and robust statistical methods, for example, helping to address pseudo-replication
problems. The database can thus help researchers in producing
broad syntheses of the effects of land use. The database is dynamic and inclusive,
and contributions from individual and large-scale data-collection efforts
are welcome.Keywords: Species turnover,
Data sharing,
Database,
Global change,
Landscape metrics,
Edge effects,
Forest fragmentation,
Matrix contrast,
Bioinformatic
The pandemic as a conservation marketing intervention: could COVID-19 lower global demand for wildlife products?
We wished to assess whether the COVID-19 pandemic, thought to have a zoonotic origin, may lead
to a reduction in consumer demand for wildlife products. In 2018 we surveyed the effect of demand
reduction messaging on consumersâ desire to own exotic pets with 1,000 respondents in each of
Brazil, China, the USA and Vietnam. In July 2020, during the pandemic, we repeated the survey
with 100 new respondents in each country. Mean desire to own a given exotic pet was 40-60%
lower in 2020 during the pandemic, but only for respondents from Brazil, China and the USA, and
only for the group of respondents who had high a priori purchase likelihoods: those who had
already owned an exotic pet. The stated desire to own of non-owners was no different in 2020, but
this group already had extremely low purchase likelihoods. Vietnamese pet owners, in contrast to
those in other countries, exhibited higher purchase desire during the pandemic than previously. We
speculate that this arose because Vietnam has a long history of dealing with epidemic disease, had
no COVID-19 related deaths by the time of survey, and so population uncertainty about the
consequences of exotic pet ownership may have decreased. While limited, our initial evidence
indicates that the global pandemic is unlikely to permanently curb demand for wildlife products
The effect of priming, nationality and greenwashing on preferences for wildlife tourist attractions
Many wildlife tourist attractions (WTAs) have negative impacts on animal welfare and species conservation. In the absence of regulation, raising standards requires tourists to create market pressure by discerning the likely impacts of WTAs, and choosing to attend those with benefits. We created a novel, experimental survey to examine whether priming tourists to engage with the ethical dimension of their choice of WTA may stimulate them to prefer WTAs that are beneficial for wildlife. Our experimental survey comprised 10 mock webpages, mimicking promotional materials for existing types of WTA, five designed to represent beneficial (âgoodâ), and five detrimental (âbadâ) WTAs. WTAs were presented in random order via an online platform to 3,224 respondents - 1614 Chinese in China, and 1610 English speakers in Australia, Canada, UK, and USA - who rated their preference for each. Prior to the survey 1610 respondents, stratified by country, were âprimedâ by asking them introductory questions about WTAsâ likely impacts. Primed English-speaking respondents were a mean of 4.1 times more likely to select lower likelihoods of attending bad WTAs, compared with control (unprimed) respondents. Priming had a smaller effect on Chinese respondents, making them 1.5 times more likely to select lower likelihoods of attending bad WTAs. Priming made all respondents more likely to select high likelihoods of attending good WTAs, but the effect was larger for Chinese respondents (2.0 times more likely) than English-speaking respondents (1.2 times more likely). After the survey respondents were shown ratings of each WTAsâ welfare and conservation impacts, and asked to re-assess each WTA. English speaking respondents were 5 to 13 times more likely to select lower likelihoods of attending bad WTAs after seeing the ratings, while Chinese respondents were 3-4 times more likely to do so. We conclude that respondents were able to discern beneficial from detrimental WTAs, and preferred beneficial WTAs when primed to consider the likely impacts of WTAs on wildlife conservation and animal welfare, but that the effect of priming was smaller for Chinese respondents. We recommend prominently hosting accurate information on the likely impacts of WTAs in the fora in which tourists are making their decisions, to direct tourist revenue away from WTAs with poor standards, and towards those that improve individualsâ welfare, and/or support species conservation
Unethical use of wildlife in tourism: whatâs the problem, who is responsible, and what can be done?
Wildlife tourism is a huge global market, the revenue from which can promote local livelihoods and tourist education, enact conservation and improve animal welfare. Such benefits arise if wildlife tourist attractions (WTAs) prioritise ethical deliverables above financial profit, but recent work has shown that the majority of WTAs have substantial negative animal welfare and conservation impacts. In the absence of global regulatory authorities, tourist revenue has become the ultimate arbiter of what constitutes acceptable use of animals in WTAs. Tourists, however, are not adequate assessors of WTAsâ animal welfare and conservation impacts: they lack the specialist knowledge required and are subject to a number of psychological biases that obscure the ethical dimensions of decisions to attend particular WTAs. This inadequacy is evidenced, and compounded, by overwhelmingly positive reviews on TripAdvisor (the industry-leading review site), even for WTAs with objectively poor ethical standards. Our suggested solution is to empower tourists by presenting unequivocal assessments of WTAs animal welfare and conservation impacts, hosted in the fora that tourists already use to make their travel decisions. We would thereby promote a subjective norm: that tourists should consider and limit their individual negative impacts when choosing which WTAs to visit
Information about zoonotic disease risks reduces desire to own exotic pets among global consumers
Demand for exotic pets is a substantial driver of the illegal wildlife trade. Previous work has suggested that this demand could be reduced by conservation marketing messaging highlighting the potential consequences to individual purchasers, in the form of zoonotic disease risks, or legal ramifications. Such work, however, has been limited only to respondents from culturally Western countries, and has not accounted for how underlying attitudes to the keeping of exotic pets may influence desire to own one, or affect the effectiveness of demand reduction messaging. We surveyed 1,000 respondents in each of Brazil, China, USA and Vietnam, showing each five mammal, bird, and reptile pets in random order. Each pet was accompanied with either a âcontrolâ statement, describing the species' diet, or one of four types of âtreatmentâ statement describing zoonotic disease, animal welfare, legal or species conservation consequences. Respondents were asked to rate how much they would like to own the pet on a 1â10 scale. All respondents demonstrated decreased desire to own a given exotic when shown any of the types of treatment information, but disease information provoked the greatest decrease, relative to controls (a mean decrease of 26.9%, compared with 16.2, 17.9, and 18.9% for legality, welfare and conservation information, respectively). We also found that respondents with the highest stated likelihood of purchasing pets possessed a series of beliefs that could facilitate this purchase while maintaining an ethical self-image: in particular they believed that shops were well-regulated, and that they were able to distinguish captively-bred from wild caught animals. In summary all respondents of any nationality were motivated particularly to avoid the risk of zoonotic disease, and we recommend that demand reduction campaigns leverage this desire, particularly in the new context of COVID-19