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UK DNA working group eDNA week, January 2022
Get PDFAbstractHere, we report on eDNA week, an international conference held online as a five‐day series of webinars from January 17, 2022, to January 21, 2022. The conference was organized by the UK DNA working group, which has witnessed considerable growth and application of eDNA research since its founding and first conference in 2014. The 2022 event, held online due to the COVID‐19 pandemic, provided an opportunity to invite international researchers who are leading the field, without the usual constraints of conference location. Compared with the previous UK‐based in‐person conferences, there was greater international participation amongst the 514 people who registered to attend the event. To emphasize the importance of collaboration between sectors in driving forward DNA monitoring, a session was devoted to presentations by participants from governmental agencies, and another to those from commercial companies developing and utilizing DNA tools. The industry and stakeholder sessions were accompanied by state‐of‐the‐art presentations delivered by a global group of DNA/eDNA researchers from 11 countries. These sessions were complemented by an open forum session for reflection and discussion
Molecular phylogeny reveals distinct evolutionary lineages of the banded krait, Bungarus fasciatus (Squamata, Elapidae) in Asia
Get PDFThe banded krait, Bungarus fasciatus is a widespread elapid snake, likely to comprise several distinct species in different geographic regions of Asia. Therefore, based on molecular phylogenetics and comparative morphology data, we present an overview of the systematic composition of the species to delimit potential biogeographic boundaries. Our phylogenetic analyses, based on four mitochondrial genes, reveal the existence of at least three evolutionary lineages within B. fasciatus, corresponding to Indo-Myanmar, Sundaic and eastern Asian lineages. We are convinced that there are at least three taxonomic entities within the nomen B. fasciatus and restrict the distribution of B. fasciatus sensu stricto to the Indo-Myanmar region. We also provide additional natural history data of the taxon from eastern India. Finally, we advocate further studies to establish the degree of reproductive isolation among these diverging evolutionary lineages and to reassess the systematic status of this species complex especially the Sundaic and eastern Asian lineages
Lutispora saccharofermentans sp. nov., a mesophilic, non-spore-forming bacterium isolated from a lab-scale methanogenic landfill bioreactor digesting anaerobic sludge, and emendation of the genus Lutispora to include species which are non-spore-forming and mesophilic
Get PDFA novel anaerobic, mesophilic, non-spore-forming bacterium (strain m25 ) was isolated from methanogenic enrichment cultures obtained from a lab-scale methanogenic landfill bioreactor containing anaerobic digester sludge. Cells were Gram-stain-negative, catalase-positive, oxidase-negative, rod-shaped, and motile by means of a flagellum. The genomic DNA G+C content was 40.11 mol%. The optimal NaCl concentration, temperature and pH for growth were 2.5 g l , 35 °C and at pH 7.0, respectively. Strain m25 was able to grow in the absence of yeast extract on glycerol, pyruvate, arginine and cysteine. In the presence of 0.2 % yeast extract, strain m25 grew on carbohydrates and was able to use glucose, cellobiose, fructose, raffinose and galactose. The novel strain could utilize glycerol, urea, pyruvate, peptone and tryptone. The major fatty acids were iso-C , C , C DMA (dimethyl acetal) and iso-C DMA. Phylogenetic analysis based on 16S rRNA gene sequences indicated that the new isolate was closely related to EBR46 (95.02 % 16S rRNA gene sequence similarity). Genome relatedness was determined using both average nucleotide identity and amino acid identity analyses, the results of which both strongly supported that strain m25 belongs to the genus . Based on its unique phylogenetic features, strain m25 is considered to represent a novel species within the genus . Moreover, based on its unique physiologic features, mainly the lack of spore formation, a proposal to amend the genus is also provided to include the non-spore-forming and mesophilic species. sp. nov. is proposed. The type strain of the species is m25 (=DSM 112749 =ATCC TSD-268 )
Leaching of phthalate acid esters from plastic mulch films and their degradation in response to UV irradiation and contrasting soil conditions
Get PDFPhthalate acid esters (PAEs) are commonly used plastic additives, not chemically bound to the plastic that migrate into surrounding environments, posing a threat to environmental and human health. Dibutyl phthalate (DBP) and di(2-ethylhexyl) phthalate (DEHP) are two common PAEs found in agricultural soils, where degradation is attributed to microbial decomposition. Yet the impact of the plastic matrix on PAE degradation rates is poorly understood. Using 14C-labelled DBP and DEHP we show that migration from the plastic matrix into soil represents a key rate limiting step in their bioavailability and subsequent degradation. Incorporating PAEs into plastic film decreased their degradation in soil, DBP (DEHP) from 79% to 21% (9% t
Enzymes for consumer products to achieve climate neutrality
Get PDFLay Summary: Accumulated greenhouse gas emissions are expected to increase from 36.2 to 60 gigatons over the next three decades. The global surface temperature has increased by +1.09°C since 2001, and might increase by +2.2°C in 2100, +3.6°C in 2200 and +4.6°C in 2500. These emissions and temperature rise cannot be reduced in their entirety, but they can be lowered by using enzymes. Enzymes are proteins that catalyze biochemical reactions that make life possible since 3.8 billion years ago. Scientists have been able to ‘domesticate’ them in such a way that enzymes, and their engineered variants, are now key players of the circular economy. With a world production of 117 kilo-tons and a trade of 14.5 billion-dollars, they have the potential to annually decrease CO2 emissions by 1–2.5 billion-tons, the carbon demand to synthesize chemicals by 200 million-tons, the amount of chemicals by 90 million-tons, and the economic losses derived from global warming by 0.5%, while promoting biodiversity and our planet’s health. Our success to increase these benefits will depend on better integration of enzymatic solutions in different sectors
Topic sensitivity still affects honest responding, even when specialized questioning techniques are used
Get PDFTo develop more effective interventions, conservationists require robust information about the proportion of people who break conservation rules (such as those relating to protected species, or protected area legislation). Developed to obtain more accurate estimates of sensitive behaviors, including rule-breaking, specialized questioning techniques such as Randomized Response Techniques (RRTs) are increasingly applied in conservation, but with mixed evidence of their effectiveness. We use a forced-response RRT to estimate the prevalence of five rule-breaking behaviors in communities living around the Ruaha–Rungwa ecosystem in Tanzania. Prevalence estimates obtained for all behaviors were negative or did not differ significantly from zero, suggesting the RRT did not work as expected and that respondents felt inadequately protected. To investigate, we carried out a second study to explore how topic sensitivity influenced respondents' propensity to follow RRT instructions. Results from this experimental study revealed respondents understood instructions well (~88% of responses were correct) but that propensity to follow RRT instructions was significantly influenced by the behavior asked about, and the type of answer they were required to provide. Our two studies highlight that even if RRTs are well understood by respondents, where topics are sensitive and respondents are wary of researchers, their use does not necessarily encourage more honest responding
A modelling approach to assessing the environmental impacts of harvesting marine bivalves from natural populations
Get PDFProportional-resonant based control strategy for grid-connected packed-E cell inverters with Lyapunov filter-based PLL
Get PDFA proportional-resonant (PR)-based current control strategy for grid-connected packed-E cell (PEC) inverter is presented. Unlike the existing control strategies, which are based on proportional-integral controller, developed for packed-U cell and PEC inverters, the proposed PR-based control strategy achieves zero steady-state error in the grid current. Furthermore, it eliminates the necessity of employing the control loop for regulating the dc capacitor voltages. Also, the grid current synchronization is achieved by using a Lyapunov filter-based phase locked loop (PLL). The consequence of using Lyapunov filter-based PLL is that sinusoidal synchronization signal can be extracted from the distorted grid voltage. The performances of the proposed control strategy under steady-state, load variation and non-ideal grid voltage are investigated on a laboratory-scale experimental prototype. It is reported that the control of both dc- and ac-side variables of the system are accomplished
Taxonomic investigation of the zooplanktivorous Lake Malawi cichlids Copadichromis mloto (Iles) and C. virginalis (Iles)
Get PDFThe taxonomic status of the zooplanktivorous cichlids Copadichromis mloto and C. virginalis has been confused since their original descriptions by lles in 1960. Whilst two forms of C. virginalis, ‘Kaduna’ and ‘Kajose’, were distinguished in the type material, C. mloto has not been positively identified since its original description. Here we re-examined the types as well as 54 recently collected specimens from multiple sampling locations. Genome sequencing of 51 recent specimens revealed two closely related but reciprocally monophyletic clades. Geometric morphological analysis indicated that one clade morphologically encompasses the type specimens of C. virginalis identified by Iles as the Kaduna form, including the holotype, whilst the other clade encompasses not only the paratypes identified as the Kajose form, but also the type series of C. mloto. Given that all three forms in Iles’s type series are from the same locality, that there are no meristic or character states to differentiate them and that there are no records of adult male C. mloto in breeding colours, we conclude that the Kajose form previously identified as C. virginalis represents relatively deeper bodied sexually active or maturing individuals of C. mloto
Mineralogy affects prokaryotic community composition in an acidic metal mine
Get PDFThe microbial ecology of acidic mine and sulfide cave ecosystems is well characterised with respect to aquatic communities, typically revealing low taxonomic complexity and dominance by a relatively limited number of cosmopolitan acidophilic bacterial and archaeal taxa. Whilst pH, temperature, and geochemistry are recognised drivers of diversity in these ecosystems, the specific question of a possible influence of substratum mineralogy on microbial community composition remains unanswered. Here we address this void, using 81 subterranean mineral samples from a low temperature abandoned, acidic, sulfide ore mine system at Mynydd Parys (Parys Mountain in English), Wales, UK. Four primary and 15 secondary minerals were identified via x-ray diffraction, each sample containing a maximum of five and an average of two minerals. The mineralogy of primary (e.g. pyrite and quartz) and secondary (e.g. melanterite and pisanite) minerals was significantly correlated with prokaryotic community structure at multiple taxonomic levels, implying that the mineralosphere effect reported in less extreme terrestrial environments is also implicated in driving prokaryotic community composition in extremely acidic, base metal-bearing sulfide mineralisation at Mynydd Parys. Twenty phyla were identified, nine of which were abundant (mean relative abundance >1%). While taxa characteristic of acidic mines were detected, for example Leptospirillum (phylum Nitrospirae), Acidithiobacillus (phylum Proteobacteria), Sulfobacillus (phylum Firmicutes) and Ferroplasma (phylum Euryarchaeota), their abundance in individual samples was highly variable. Indeed, in the majority of the 81 samples investigated the abundance of these and other typical acidic mine taxa was low, with 25% of samples devoid of sequences from recognised acidic mine taxa. Most notable amongst the bacterial taxa not previously reported in such environments were the recently cultivated Muribaculaceae family (phylum Bacteroidetes), which often dominated Mynydd Parys samples regardless of their mineralogical content. Our results pose further questions regarding the mechanisms by which taxa not previously reported in such extreme environments appear to survive in Mynydd Parys, opening up research pathways for exploring the biodiversity drivers underlying microbial community composition and function in extremely acidic mine environments