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A new species of deep-water Lethrinops (Cichlidae) from Lake Malawi
Get PDFAbstract A new species of cichlid fish, Lethrinops atrilabris is described from specimens collected by trawling at a depth of around 90?m off Monkey Bay, southern Lake Malawi. It is assigned to the genus Lethrinops on the basis of its vertical flank barring, lack of enlarged cephalic lateral line canal pores and the form of the lower jaw dental arcade. It can be distinguished from congeneric species by its male breeding dress of contrasting flank barring and dark ventral surface, most strikingly on the lips, throat and chest, its relatively small known maximum size
City-wide wastewater genomic surveillance through the successive emergence of SARS-CoV-2 Alpha and Delta variants
Get PDFGenomic surveillance of SARS-CoV-2 has provided a critical evidence base for public health decisions throughout the pandemic. Sequencing data from clinical cases has helped to understand disease transmission and the spread of novel variants. Genomic wastewater surveillance can offer important, complementary information by providing frequency estimates of all variants circulating in a population without sampling biases. Here we show that genomic SARS-CoV-2 wastewater surveillance can detect fine-scale differences within urban centres, specifically within the city of Liverpool, UK, during the emergence of Alpha and Delta variants between November 2020 and June 2021. Furthermore, wastewater and clinical sequencing match well in the estimated timing of new variant rises and the first detection of a new variant in a given area may occur in either clinical or wastewater samples. The study's main limitation was sample quality when infection prevalence was low in spring 2021, resulting in a lower resolution of the rise of the Delta variant compared to the rise of the Alpha variant in the previous winter. The correspondence between wastewater and clinical variant frequencies demonstrates the reliability of wastewater surveillance. However, discrepancies in the first detection of the Alpha variant between the two approaches highlight that wastewater monitoring can also capture missing information, possibly resulting from asymptomatic cases or communities less engaged with testing programmes, as found by a simultaneous surge testing effort across the city
A quantitative synthesis of and predictive framework for studying winter warming effects in reptiles
Get PDFIncreases in temperature related to global warming have important implications for organismal fitness. For ectotherms inhabiting temperate regions, ‘winter warming’ is likely to be a key source of the thermal variation experienced in future years. Studies focusing on the active season predict largely positive responses to warming in the reptiles; however, overlooking potentially deleterious consequences of warming during the inactive season could lead to biased assessments of climate change vulnerability. Here, we review the overwinter ecology of reptiles, and test specific predictions about the effects of warming winters, by performing a meta-analysis of all studies testing winter warming effects on reptile traits to date. We collated information from observational studies measuring responses to natural variation in temperature in more than one winter season, and experimental studies which manipulated ambient temperature during the winter season. Available evidence supports that most reptiles will advance phenologies with rising winter temperatures, which could positively affect fitness by prolonging the active season although effects of these shifts are poorly understood. Conversely, evidence for shifts in survivorship and body condition in response to warming winters was equivocal, with disruptions to biological rhythms potentially leading to unforeseen fitness ramifications. Our results suggest that the effects of warming winters on reptile species are likely to be important but highlight the need for more data and greater integration of experimental and observational approaches. To improve future understanding, we recap major knowledge gaps in the published literature of winter warming effects in reptiles and outline a framework for future research
Metamorphic common toads keep chytrid infection under control, but at a cost
Get PDFBatrachochytrium dendrobatidis(Bd) causes chytridiomycosis, an infectious disease of amphibians, which has contributed to population declines in hundreds of species worldwide. Common toads (Bufo bufo) exhibit low resistance and relatively high tolerance to Bd infection, which may partly be attributable to bufadienolide toxins secreted in their granular skin glands. Bufadienolides are known to provide an effective defense against several pathogens, parasites, and predators. The toxin production of bufonids is a plastic trait, inducible by several environmental factors. Here, we experimentally infected juvenile common toads with Bd and investigated if the toadlets could clear the infection over time, whether the infection induced bufadienolide production, and whether the infection caused decreased body mass. We found that prevalence remained 100% throughout the entire experimental period, but infection intensity did not increase and it was significantly lower on day 30 than on day 20. At the same time, compared to controls, infected toadlets produced lesser amounts of bufadienolides and their body mass was also lower. These results suggest that although young toadlets may not be able to clear Bd infection on their own, they may be able to keep infection intensities under control. Nonetheless, even if toadlets do not succumb to the disease, the costs of chronic infection may still compromise their fitness.<br/
Mynd: A Sonic Representation of a Seemingly Quiet and Vast Landscape - Its Ecology, Geology, Past and Present Histories.
Get PDFSafeguarding Imperiled Biodiversity and Evolutionary Processes in the Wallacea Center of Endemism
Get PDFWallacea—the meeting point between the Asian and Australian fauna—is one of the world's largest centers of endemism. Twenty-three million years of complex geological history have given rise to a living laboratory for the study of evolution and biodiversity, highly vulnerable to anthropogenic pressures. In the present article, we review the historic and contemporary processes shaping Wallacea's biodiversity and explore ways to conserve its unique ecosystems. Although remoteness has spared many Wallacean islands from the severe overexploitation that characterizes many tropical regions, industrial-scale expansion of agriculture, mining, aquaculture and fisheries is damaging terrestrial and aquatic ecosystems, denuding endemics from communities, and threatening a long-term legacy of impoverished human populations. An impending biodiversity catastrophe demands collaborative actions to improve community-based management, minimize environmental impacts, monitor threatened species, and reduce wildlife trade. Securing a positive future for Wallacea's imperiled ecosystems requires a fundamental shift away from managing marine and terrestrial realms independently
Roots and rhizospheric soil microbial community responses to tree species mixtures.
Get PDFBelow-ground processes are crucial in determining the effects of plants on ecosystem function. The root-soil interface is a highly active zone due to root exudation and nutrient uptake. However, its role in determining effectsof tree species and their interactions on the soil microbial community, ecosystem function and above-ground growth is less well known. We compared the effects of tree species monocultures and their mixture on rhizospheric microbial communities, specific functional genetic markers associated with processes in the nitrogen (N) cycle, and above-ground and below-ground growth and nutrient allocation. Two pairs of tree species were grown: Pseudotsuga menziesii and Alnus rubra; Acer pseudoplatanus and Quercus robur. Tree establishment altered soil microbial composition, but after 26 months differences amongst tree species and effects of species mixture were minor, suggesting functional redundancy in microbial communities. A greater abundance of fungi, bacteria, and specifically ammonia oxidising and denitrifying bacteria in the rhizospheric soil of the N-fixing A. rubra was the most notable trend. Mixing A. rubra with P. menziesii did produce overyielding: trees grown in mixture attained a two-fold greater (Relative Yield Total 2.03±0.52) above-ground biomass than in a mixture predicted from trees grown in monoculture. We did not observe strong trends in overyielding for A. psuedoplatanus and Q. robur. Inclusion of the Nfixing species A. rubra in admixture with P. menziesii promoted N cycling, and decreased the C:N ratios of leaf, branch, and root tissues but not soil C:N ratio for P. menziesii. Given the observed overyielding in the A. rubra with P. menziesii mixtures, we explored potential mechanistic links between functional genetic markers for nitrificationand ammonification, however we found no statistically significant effects attributable to these genetic markers. We found root area index was significantly lower in A. rubra monocultures than in admixture with P. menziesii. For both P. menziesii and A. rubra, the number of root tips was lower in mixture than monoculture, indicating physical partitioning of soil space as a result of growing in mixture. We documented additive and synergistic effects of tree species identity on above and belowground productivity, and rhizospheric microbial community development in these four tree species
Working towards diagnosing bilingual children's literacy abilities: Some key considerations for teachers in Wales
Get PDFOne area of concern within a bilingual context relates to the appropriate 'diagnostic' assessment of bilingual children’s language abilities and to the suitable application of their assessment results in practice. Communication and language difficulties are numerous and complex, and manifest themselves in a variety of ways that are captured to different degrees via standardised tests. Such tools are readily available – often in multiple forms – in some languages, such as English, but less readily available in others. This is particularly the case for minority languages such as Welsh, and this poses great difficulty when aiming for a certain type of assessment of specific language abilities. This paper outlines the current state of diagnostic assessment tools for Welsh, with a specific focus on measures of literacy abilities. Drawing on research evidence from the Welsh context, we argue for appropriate training of educators in this area, and for the urgent need to develop tools that are both language and context specific, with relevant bilingual speaker norms, that have practical applications in the classroom, to ensure equitable and relevant diagnosis and support for all children educated in Wales
Cost-effectiveness Analysis of the Dental RECUR Pragmatic Randomized Controlled Trial: Evaluating a Goal-oriented Talking Intervention to Prevent Reoccurrence of Dental Caries in Children
Get PDFAbstract: Background: The formation of dental caries is the most common chronic disease in children, and is preventable. The oral health-related quality of life has an immense impact on an individual’s daily functioning, well-being or overall quality of life. Objectives: This study aims to investigate the cost effectiveness of the Dental RECUR Brief Negotiated Interview for Oral Health (DR-BNI). This 30-minute therapeutic “talk” by a dental nurse with a parent/guardian was compared with a placebo-controlled intervention in preventing reoccurrence of dental caries in children who have had a primary tooth extracted. Methods: An economic model was developed to simulate the clinical progression of dental caries among children who have previously had a primary tooth extracted. The analysis was conducted using the UK NHS perspective. The main outcome was the incremental cost-effectiveness ratio (ICER) based on the quality-adjusted life years (QALYs). Estimates of costs and probabilities were obtained from the DR-BNI multicentre randomised controlled trial (RCT), while QALY values were obtained from published literature. Univariate and probabilistic sensitivity analyses were conducted to assess the uncertainty of the result and robustness of the model. Affordability and risk-aversion of the intervention were investigated to help decision makers make the best possible choices. Results: With an intervention cost of £6.47, the results from the RCT showed the healthcare cost for the DR-BNI intervention was £115.90 per child while the control had a healthcare cost of £119.46 per child. The QALYs gained for the prevention of reoccurrence of dental caries was higher in the DR-BNI intervention arm by 0.023 QALYs; thus, the DR-BNI was the dominant intervention. At willingness to pay threshold of £3500/QALY gained, a maximum probability of being cost effectiveness is achieved at 86%. The secondary analysis showed a cost-savings of £20.94 per participant for the prevention of at least one filling or extraction. Affordability results showed that the DR-BNI programme is affordable to the UK health system at a moderately low budget. Conclusions: This study shows the proactive talking intervention to have a very moderate cost and to be effective in providing better health related quality-of-life gains. The intervention is cost savings with a dominant ICER even with a 200% increase in the cost of intervention. The NHS will be providing better oral health for children at a better net monetary benefit-to-risk ratio by adopting the DR-BNI intervention in preventing the reoccurrence of dental fillings and extractions for each participant. Trial Registration: This trial was registered prospectively on 27th September 2013 with the trial registration number ISRCTN 24958829