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The discovery that sponges (Porifera) can fully regenerate from aggregates of dissociated cells launched them as one of the earliest experimental models to study the evolution of cell adhesion and allorecognition in animals. This process depends on an extracellular glycoprotein complex called the Aggregation Factor (AF), which is composed of proteins thought to be unique to sponges. We used quantitative proteomics to identify additional AF components and interacting proteins in the classical model, Clathria prolifera, and compared them to proteins involved in cell interactions in Bilateria. Our results confirm MAFp3/p4 proteins as the primary components of the AF but implicate related proteins with calx-beta and wreath domains as additional components. Using AlphaFold, we unveiled close structural similarities of AF components to protein domains in other animals, previously masked by the mutational decay of sequence similarity. The wreath domain, believed to be unique to the AF, was predicted to contain a central beta-sandwich of the same organization as the vWFD domain (also found in extracellular, gel-forming glycoproteins in other animals). Additionally, many copurified proteins share a conserved C-terminus, containing divergent immunoglobulin (Ig) and Fn3 domains predicted to serve as an AF-interaction interface. One of these proteins, MAF-associated protein 1, resembles Ig superfamily cell adhesion molecules and we hypothesize that it may function to link the AF to the surface of cells. Our results highlight the existence of an ancient toolkit of conserved protein domains regulating cell-cell and cell-extracellular matrix protein interactions in all animals, and likely reflect a common origin of cell adhesion and allorecognition. [ABSTRACT FROM AUTHOR]

We have characterised the northern Pacific undescribed sponge Haliclona (?gellius) sp. based on rDNA of the sponge and its associated microorganisms. The sponge is closely related to Amphimedon queenslandica from the Great Barrier Reef as the near-complete 18S rDNA sequences of both sponges were identical. The microbial fingerprint of three specimens harvested at different times and of a transplanted specimen was compared to identify stably associated microorganisms. Most bacterial phyla were detected in each sample, but only a few bacterial species were determined to be stably associated with the sponge. A sponge-specific β- and γ-Proteobacterium were abundant clones and both of them were present in three of the four specimens analysed. In addition, a Planctomycete and a Crenarchaea were detected in all sponge individuals. Both were closely related to operational taxonomic units that have been found in other sponges, but not exclusively in sponges. Interestingly, also a number of clones that are closely related to intracellular symbionts from insects and amoeba were detected.

Preparing students to be competitive in the 21st century global economy is undoubtedly one of the major goals of all educators. Studies have shown that students who have an increased exposure to engaging STEM courses at the high school level are more likely to enter STEM majors at the collegiate level and, thus, STEM industries post-graduation (Wang, 2013, p. 1082). In order to take on this national initiative, P21, the Partnership for 21st Century Learning, developed a framework that outlines key attributes of education that will prepare students for success in 21st century industry. The framework states that, when students are exposed to "the necessary support systems--standards, assessments, curriculum, and instruction, …, and learning environments--students are more engaged in the learning process and graduate better prepared to thrive in today's global economy" (Partnership for 21st Century Skills, 2008 para. 4). At the school level, this task falls to educators, specifically engineering educators who are at a unique advantage to design and implement projects that engage students in developmentally appropriate learning experiences while effectively developing their skill set for collegiate studies and/or industry. In turn, engagement and skill development can be successfully achieved through the design and implementation of open-ended projects. Open-ended projects in the engineering classroom not only engage students in learning and spark interests in real-world problem solving, but help to develop these essential 21st century skills. This article defines open-ended projects and describes how to apply open-ended process in the classroom.

In Australia, there has been a tendency to rely on quantitative indicators of university teaching quality. This has occurred partly because the indicators are perceived as objective and reliable and partly because they are relatively simple to gather and collate. A national project currently underway is based on the assumptions that teaching quality is multidimensional and that the identification and use of relevant indicators of teaching quality are dependent on the institutional environment. With a focus on student engagement, this paper outlines the research-based approach to developing indicators of teaching quality being taken by one Australian university participating in the national project. (Contains 4 figures.)

The cause of large areas of treeless Sedgeland and Scrub communities in western Tasmania, one of the wettest regions of Australia, has long puzzled ecologists, given the climatic suitability for temperate Eucalyptus and rainforests. A pervasive theory, known as the ecological drift model, is that landscape fires have created a dynamic mosaic of fire-adapted and fire-sensitive vegetation. A contrary view, known as the fire cycle model, asserts that fire patterns are a consequence, not a cause, of the mosaics, which are edaphically determined. We leveraged the opportunity presented by a large wildfire that occurred in a Sedgeland tract surrounded by Eucalyptus forest in the Huon Valley in 2019 to help discriminate between these competing models. Specifically, we sought to determine whether there was any evidence that the Sedgeland was becoming infilled with Scrub prior to the 2019 fire, and whether the fire caused the Scrub community to convert to Sedgeland. A field survey was used to assess the mortality of shrubs and their regeneration following the 2019 fire, and we used dendrochronology to determine the age of the fire-killed shrubs. We also used historical aerial photography since the 1980s to map fire scars and the distribution of Sedgeland and Scrub. We found that fire killed most shrubs in the Sedgeland and Scrub communities and initiated a cohort of shrub regeneration. Dendrochronological analysis of the fire-killed shrubs revealed that most were established approximately 40 years ago, following a fire that is apparent from aerial photography and most likely occurred around 1983. An analysis of aerial photography revealed that since 1980, the distribution of the Scrub community has remained stable, although the density of shrubs declined following the 1983 fire. The recovery of the burned Scrub areas in 1983 and the rapid regeneration of the shrubs following the 2019 fire is more consistent with the fire cycle model than the ecological drift model. These findings concord with the demonstrated stability of the Eucalyptus forest boundary at this site revealed by a separate study. The slow growth of the shrubs cautions against frequently burning Sedgelands, because it could cause the collapse of shrub populations by killing the immature cohort initiated by fire. [ABSTRACT FROM AUTHOR]

Sphagnum bogs in Australia are small, with a limited distribution, but of high conservation value. They are restricted to cool, wet environments that are typically fire free and are poorly adapted to recover from fire disturbance, unlike most Australian flora. Increased fire activity due to anthropogenic climate change is threatening Sphagnum bogs. This increased threat has stimulated interest in their restoration. Compared with the northern hemisphere, there have been few studies of the ecology of Sphagnum restoration in the southern hemisphere. Here, we report on a field experiment in Tasmania, in an area burned by an extensive fire in 2016. We investigated the role of shade, fertilizer and transplants, factors demonstrated to be important in the restoration of burnt bogs on the Australian mainland. Treatments commenced three to 4 years after the fire. Overall, we found that fire‐damaged Sphagnum recovers very slowly, and that there was no recovery in severely burned areas. The addition of shade increased recovery of damaged Sphagnum, but fertilizer was harmful, even to healthy Sphagnum. Transplants in fire‐killed Sphagnum grew poorly in both moderately and severely burnt Sphagnum areas. Our findings support the use of shading in post‐fire Sphagnum recovery projects, although further work is required to determine the optimal approach and duration of providing shade. [ABSTRACT FROM AUTHOR]

Aims: To assess clinicians' self‐reported knowledge of current policies in African oncology settings, of their personal communication practices around sharing bad news with patients, and to identify barriers to the sharing of serious news in these settings. Methods: A cross‐sectional study of cancer care providers in African oncology settings (N = 125) was conducted. Factor analysis was used to assess cross‐cultural adaptation and uptake of an evidence‐based protocol for disclosing bad news to patients with cancer and of providers' perceived barriers to disclosing bad news to patients with cancer. Analysis of Various (ANOVA) was used to assess strength of association with each dimension of these two measurement models by various categorical variables. Results: Providers from Nigeria, Kenya, Ghana, and Rwanda represented 85% of survey respondents. Two independent, psychometrically reliable, multi‐dimensional measurement models were derived to assess providers' personal communication practices and providers' perceived barriers to disclosing a cancer diagnosis. Forty percent (40%) of respondent nurses but only 20% of respondent physicians had had formal communications skills training. Approximately 20%–25% of respondent physicians and nurses reported having a consistent plan or strategy for communicating bad news to their cancer patients. Conclusions: Results show that effective communication about cancer diagnosis and prognosis requires an appreciation and clinical skill set that blends an understanding of cancer‐related internalized stigmas harbored by patient and family, dilemmas posed by treatment affordability, and the need to navigate family wishes about cancer‐related diagnoses in the context of African oncology settings. Findings underscore the need for culturally grounded communications research and program design. [ABSTRACT FROM AUTHOR]

Choanoflagellates are the closest known relatives of metazoans. To discover potential molecular mechanisms underlying the evolution of metazoan multicellularity, we sequenced and analysed the genome of the unicellular choanoflagellate Monosiga [...]