Carbon dioxide removal via weathering of sugarcane mill ash under different soil conditions

Sugarcane mill ash has been suggested as having high potential for carbon dioxide removal (CDR) via enhanced weathering (EW), but this had not been quantitatively assessed. The aims of this study were to 1) assess the CDR potential of various sugarcane mill ashes via EW, and 2) investigate the impact of soil conditions and mill ash properties on the CDR. This was done by characterising physical and chemical properties of five mill ashes from Australia and simulating weathering using a one-dimensional reactive transport model. The model was parameterised to simulate weathering of 100 t/ha of wet ash (47–65% water) or crushed basalt for 15 years under various combinations of soil pH and carbon dioxide partial pressure (pCO2). A sensitivity analysis was undertaken in a two-level factorial design to test the effect of pH, pH buffering, material surface area, infiltration rate, plant uptake of nutrients, organic matter cation exchange surfaces, and pCO2 on modelled CDR. The simulated CDR of the mill ashes was significantly less than the basalt (p 0.05). Weathering of mill ash removed 0.0–4.0 t CO2/ha (0.00–0.040 t CO2/t wet ash) cumulatively, similar to some basalts and olivine modelled in the literature. The theoretical maximum CDR of the mill ashes (based on amount of weatherable material applied) was achieved in around 5 years. The estimate of CDR varied by orders of magnitude depending on conditions. It was least when initial soil solution pH was lowest (4.5, unbuffered), pH was at 6.5 or less with constant buffering, and pCO2 was low (600 ppm). CDR was also significantly lower when calculated directly from accumulation of carbon in dissolved and solid phases rather than stoichiometrically from cation release. The effects of pH and pH buffering quantified here may explain low measured CDR from EW in field trials on acidic soils and highlight the need for more realistic modelling of pH buffering capacity. Overall, mill ash shows high potential for CDR via EW, especially if lifecycle benefits are considered, although this must be validated in the field

Phylogenomics of the genus Tursiops and closely related Delphininae reveals extensive reticulation among lineages and provides inference about eco-evolutionary drivers

Phylogeographic inference has provided extensive insight into the relative roles of geographical isolation and ecological processes during evolutionary radiations. However, the importance of cross-lineage admixture in facilitating adaptive radiations is increasingly being recognised, and suggested as a main cause of phylogenetic uncertainty. In this study, we used a double digest RADseq protocol to provide a high resolution (∼ 4 Million bp) nuclear phylogeny of the Delphininae. Phylogenetic resolution of this group has been especially intractable, likely because it has experienced a recent species radiation. We carried out cross-lineage reticulation analyses, and tested for several sources of potential bias in determining phylogenies from genome sampling data. We assessed the divergence time and historical demography of T. truncatus and T. aduncus by sequencing the T. aduncus genome and comparing it with the T. truncatus reference genome. Our results suggest monophyly for the genus Tursiops, with the recently proposed T. australis species falling within the T. aduncus lineage. We also show the presence of extensive cross-lineage gene flow between pelagic and European coastal ecotypes of T. truncatus, as well as in the early stages of diversification between spotted (Stenella frontalis; Stenella attenuata), spinner (Stenella longirostris), striped (Stenella coeruleoalba), common (Delphinus delphis), and Fraser’s (Lagenodelphis hosei) dolphins. Our study suggests that cross-lineage gene flow in this group has been more extensive and complex than previously thought. In the context of biogeography and local habitat dependence, these results improve our understanding of the evolutionary processes determining the history of this lineage

Malaysian fruit bats phylogeny inferred using Ribosomal RNA

Fourteen species of the Malaysian fruit bats (Pteropodidae) were used in this DNA taxonomy using 1,334bp of the 12S ribosomal RNA (rRNA), transfer RNA (tRNA) valine and 16S rRNA gene segments. Previous studies using DNA found contradictions between morphology and molecular data in inferring the phylogeny of the fruit bats proposed by Andersen (1912). Our phylogenetic analysis using the neighbor-joining and the maximum parsimony methods did not support the monophyly of the subfamily Macroglossinae and the cynopterine group of the subfamily Pteropodinae as proposed by classical taxonomists. This is congruent with previous molecular studies. Here, we provide the first registered 12S rRNA, tRNA valine and 16S rRNA sequence records for Dyacopterus spadiceus in the GenBank database. This study represents the first attempt to infer the phylogenetic relationship of fruit bats from Malaysia using molecular methods

Slob, a Novel Protein that Interacts with the Slowpoke Calcium-Dependent Potassium Channel

AbstractSlob, a novel protein that binds to the carboxy-terminal domain of the Drosophila Slowpoke (dSlo) calcium-dependent potassium channel, was identified with a yeast two-hybrid screen. Slob and dSlo coimmunoprecipitate from Drosophila heads and heterologous host cells, suggesting that they interact in vivo. Slob also coimmunoprecipitates with the Drosophila EAG potassium channel but not with Drosophila Shaker, mouse Slowpoke, or rat KV1.3. Confocal fluorescence microscopy demonstrates that Slob and dSlo redistribute in cotransfected cells and are colocalized in large intracellular structures. Direct application of Slob to the cytoplasmic face of detached membrane patches containing dSlo channels leads to an increase in channel activity. Slob may represent a new class of multi-functional channel-binding proteins

Reticulate Evolution and Marine Organisms: The Final Frontier?

The role that reticulate evolution (i.e., via lateral transfer, viral recombination and/or introgressive hybridization) has played in the origin and adaptation of individual taxa and even entire clades continues to be tested for all domains of life. Though falsified for some groups, the hypothesis of divergence in the face of gene flow is becoming accepted as a major facilitator of evolutionary change for many microorganisms, plants and animals. Yet, the effect of reticulate evolutionary change in certain assemblages has been doubted, either due to an actual dearth of genetic exchange among the lineages belonging to these clades or because of a lack of appropriate data to test alternative hypotheses. Marine organisms represent such an assemblage. In the past half-century, some evolutionary biologists interested in the origin and trajectory of marine organisms, particularly animals, have posited that horizontal transfer, introgression and hybrid speciation have been rare. In this review, we provide examples of such genetic exchange that have come to light largely as a result of analyses of molecular markers. Comparisons among these markers and between these loci and morphological characters have provided numerous examples of marine microorganisms, plants and animals that possess the signature of mosaic genomes

A neuronal enhancer network upstream of MEF2C is compromised in patients with Rett-like characteristics

Mutations in myocyte enhancer factor 2C (MEF2C), an important transcription factor in neurodevelopment, are associated with a Rett-like syndrome. Structural variants (SVs) upstream of MEF2C, which do not disrupt the gene itself, have also been found in patients with a similar phenotype, suggesting that disruption of MEF2C regulatory elements can also cause a Rett-like phenotype. To characterize those elements that regulate MEF2C during neural development and that are affected by these SVs, we used genomic tools coupled with both in vitro and in vivo functional assays. Through circularized chromosome conformation capture sequencing (4C-seq) and the assay for transposase-accessible chromatin using sequencing (ATAC-seq), we revealed a complex interaction network in which the MEF2C promoter physically contacts several distal enhancers that are deleted or translocated by disease-associated SVs. A total of 16 selected candidate regulatory sequences were tested for enhancer activity in vitro, with 14 found to be functional enhancers. Further analyses of their in vivo activity in zebrafish showed that each of these enhancers has a distinct activity pattern during development, with eight enhancers displaying neuronal activity. In summary, our results disentangle a complex regulatory network governing neuronal MEF2C expression that involves multiple distal enhancers. In addition, the characterized neuronal enhancers pose as novel candidates to screen for mutations in neurodevelopmental disorders, such as Rett-like syndrome

Communication modes and performance of virtual design teams in an undergraduate building project

Effective communication between parties in distributed design teams is essential for successful construction projects. However, there is little consensus and understanding on the factors influencing the distanced communication between these multidisciplinary parties. Many effective practices that are applicable to traditional collocated teams may no longer be relevant and require a thorough examination. This paper reports an on-going research project that aims to investigate the factors influencing the communication effectiveness of virtual design teams in a case project undertaken by final-year undergraduate students in two institutions in Canada and the UK. The empirical work involved a questionnaire survey of 69 students, comprising 32 UK (civil/structural engineering) and 37 Canadian (architectural) students. The findings suggest that there is tendency for different communication modes used by the two professions, with architects preferring visual and kinesthetic modes, and civil/structural engineers preferring aural and read/write modes, although this was not statistically significant (p=0.286). Higher levels of trust could be sustained by providing evidence of consistent performance over the course of the project. The architectural students and female participants are more likely to exhibit higher levels of trust to their counterparts and higher levels of satisfaction with team working. The findings reveal the potential influence of disciplinary training on the preferred communication modes and the development of effective virtual collaboration. Additionally, the research provides material for further reflection and may serve as a useful consideration for future development of a guiding framework for effective training of built environment professionals

Connectivity between coastal lagoons and sea: asymmetrical effects on assemblages' and populations' structure

Connectivity among marine populations plays a fundamental role in the dynamic of metapopulations and communities. Moreover, genetic connectivity is important for the evolutionary history and adaptive capability of species while demographic connectivity is essential to maintain ecological processes. In coastal lagoons, isolation degree or confinement is considered the main factor structuring biological assemblages. These environments also function as nursery areas for many marine species that colonize the lagoons as larvae or juveniles, returning to the sea for reproduction. It is therefore essential to know the connectivity between lagoons and sea for the management of biodiversity and the exploitation of coastal living resources. This work anases the role that connectivity between coastal lagoons and sea plays in the assemblages and subpopulations structure of the first. To this purpose, a finite element hydrodynamic model was used coupled with a lagrangian module to simulate the potential exchange of organisms between Mar Menor lagoon (Western Mediterranean) and the adjacent sea. Connectivity parameters from 40 stations, located inside and outside the Mar Menor, have been estimated. The outcomes of the eight simulations carried out were compared with field data, including ichthyoplankton species composition and genetic fluxes in 6 species with different life stories. The results suggest that pelagic larval phases are longer than expected or the species can extend PLD within certain limits if the conditions for the settlement are not adequate. Repetition can improve the chance of self-recruitment, coupling larval duration, competency period and finding the adequate location for settlement. The results also show that connectivity between all lagoon and Mediterranean stations is very low and is independent of geographical distance. There is a strong asymmetry in the probability of receiving particles, being lower the probability of colonization of the lagoon stations from the sea than vice versa. Despite its low values, connectivity can explain up to 65% of the similarities in species composition of the ichthyoplankton and between 30 and 96% of the variance in genetic differentiation of the studied species. The low value of connectivity and colonization rates is enough, however, to maintain the genetic fluxes between populations and, at the same time, restricted connectivity can play an important role in maintaining high diversity and heterogeneous assemblage structure

Adjuvant therapy for children treated by enucleation at diagnosis of retinoblastoma

Introduction Advanced localized retinoblastoma can be cured by enucleation, but extraocular spread of retinoblastoma cells is associated with a high mortality. Risk-stratified adjuvant treatment with chemotherapy and radiotherapy has been shown to reduce the risk for extraocular relapse in children with histopathological risk factors. Methods Data of 184 patients with retinoblastoma and primary enucleation were collected in a prospective, multicenter, observational study between 2013 and 2020. The clinical characteristics were evaluated as risk factors and progression-free and overall survival rates were compared. Results Seventy-one percent of 184 children with retinoblastoma treated with primary enucleation were diagnosed with low risk histopathological factors (pT1/pT2a) and received no adjuvant therapy. Children with intermediate risk (pT2b,pT3; 48 children, 26.0%) and high risk for metastasis (pT4; 5 children, 2.7%) received risk-stratified adjuvant treatment. None of the children with low risk or intermediate risk (pT1-pT3) relapsed, but two of five children with high-risk retinoblastoma (pT4) developed extraocular relapses and one deceased. The 2-year progression-free survival rate and 2-year overall survival rate was 100% for children with pT1-3 retinoblastoma. However, the 2-year progression-free survival rate and 2-year overall survival rate for children with pT4 was statistically notably reduced with 2 of 5 children developing progression and 1 death among the 5 children within 2 years after diagnosis. Conclusion Primary enucleation alone and with additional risk-stratified adjuvant chemotherapy treatment provides high cure rates in patients with pT1-3 retinoblastoma, but children with pT4 retinoblastoma remain at high risk to develop extraocular retinoblastoma. International prospective clinical trials are required to evaluate reduction of intensity of adjuvant chemotherapy in some risk groups (pT2, pT3) and intensification for pT4 retinoblastoma