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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]

The article highlights the importance of maximizing the impact of Science, Technology, Engineering, and Mathematics (STEM) education by investing in professional learning opportunities, collaborating across grade levels, and integrating cross-cutting practices. It highlights the significance of fostering professional learning communities to enhance teaching practices and collectively contribute to the ongoing advancement of STEM education.

The authors discuss the study which reveals the GTPase activating protein (GAP) using evolutionary rate covariation (ERC) analysis with traditional experimental techniques in cell biology. The authors highlight the strength of the ERC method and its principles as well as its potential in aiding functional discovery. The authors believe that the study demonstrates an effective workflow which helped bridge the gap between evolutionary theory and experimental research.

The article discusses the role of open-ended projects in yielding best results and fostering the highest level of thinking in reference to telemedicine example. Topics included are significance of an open-ended project that allows students to develop and create aspects of the project based on their knowledge, development of an effective workspace to carry out the project work, and turning the chosen concept into a testable prototype.

Nuclear magnetic resonance (NMR) studies of larger proteins are hampered by difficulties in assigning NMR resonances. Human intervention is typically required to identify NMR signals in 3D spectra, and subsequent procedures depend on the accuracy of this so-called peak picking. We present a method that provides sequential connectivities through correlation maps constructed with covariance NMR, bypassing the need for preliminary peak picking. We introduce two novel techniques to minimize false correlations and merge the information from all original 3D spectra. First, we take spectral derivatives prior to performing covariance to emphasize coincident peak maxima. Second, we multiply covariance maps calculated with different 3D spectra to destroy erroneous sequential correlations. The maps are easy to use and can readily be generated from conventional triple-resonance experiments. Advantages of the method are demonstrated on a 37 kDa nonribosomal peptide synthetase domain subject to spectral overlap. [ABSTRACT FROM AUTHOR]

The article discusses the advancements in the development of continuous glucose monitoring technologies that are used to monitor blood glucose level and also reflects on the use of biocompatible materials in the electro-chemical glucose sensors in devices. It also reflects on the challenges associated with the development of biocompatible coatings for glucose sensors. It mentions several techniques for glucose monitoring such as iontophoresis, microdialysis and optical coherence tomography.

Summary: Regulation of protein phosphatase 1 (PP1) is controlled by a diverse array of regulatory proteins. However, how these proteins direct PP1 specificity is not well understood. More than one-third of the nuclear pool of PP1 forms a holoenzyme with the nuclear inhibitor of PP1, NIPP1, to regulate chromatin remodeling, among other essential biological functions. Here, we show that the PP1-binding domain of NIPP1 is an intrinsically disordered protein, which binds PP1 in an unexpected manner. NIPP1 forms an α helix that engages PP1 at a unique interaction site, using polar rather than hydrophobic contacts. Importantly, the structure also reveals a shared PP1 interaction site outside of the RVxF motif, the ΦΦ motif. Finally, we show that NIPP1:PP1 substrate selectivity is determined by altered electrostatics and enhanced substrate localization. Together, our results provide the molecular basis by which NIPP1 directs PP1 substrate specificity in the nucleus. [ABSTRACT FROM AUTHOR]

Abstract: Non-invasive treatment of injuries and disorders affecting bone and connective tissue remains a significant challenge facing the medical community. A treatment route that has recently been proposed is nitric oxide (NO) therapy. Nitric oxide plays several important roles in physiology with many conditions lacking adequate levels of NO. As NO is a radical, localized delivery via NO donors is essential to promoting biological activity. Herein, we review current literature related to therapeutic NO delivery in the treatment of bone, skin and tendon repair. [Copyright &y& Elsevier]

The evolution of Cadherins, which are essential for metazoan multi-cellularity and restricted to metazoans and their closest relatives, has special relevance for understanding metazoan origins. To re-construct the ancestry and evolution of Cadherin gene families, we analyzed the genomes of the choanoflagellate Salpingoeca rosetta, the unicellular outgroup of choanoflagellates and metazoans Cap-saspora owczarzaki, and a draft genome assembly from the homo-scleromorph sponge Oscarella carmela. Our finding of a Cadherin gene in C. owczarzaki reveals that Cadherins predate the divergence of the C. owczarzaki, choanoflagellate, and metazoan lineages. Data from these analyses also suggest that the last common ancestor of metazoans and choanoflagellates contained representatives of at least three Cadherin families, lefftyrin, coherin, and hedgling. Additionally, we find that an O. Carmela classical Cadherin has predicted structural features that, in bilaterian classical Cadherins, facilitate binding to the cytoplasmic protein β-catenin and, thereby, promote cadherin-mediated cell adhesion. In contrast with premetazoan Cadherin families (i.e., those conserved between choanoflagellates and metazoans), the later appearance of classical Cadherins coincides with metazoan origins. [ABSTRACT FROM AUTHOR]

The in vivo glucose recovery of subcutaneously implanted nitric oxide (NO)-releasing microdialysis probes was evaluated in a rat model using saturated NO solutions to steadily release NO. Such methodology resulted in a constant NO flux of 162 pmol cm-2 s-1 from the probe membrane over 8 h of perfusion daily. The in vivo effects of enhanced localized NO were evaluated by monitoring glucose recovery over a 14 day period, with histological analysis thereafter. A difference in glucose recovery was observed starting at 7 days for probes releasing NO relative to controls. Histological analysis at 14 days revealed lessened inflammatory cell density at the probe surface and decreased capsule thickness. Collectively, the results suggest that intermittent sustained NO release from implant surfaces may improve glucose diffusion for subcutaneously implanted sensors by mitigating the foreign body reaction. [ABSTRACT FROM AUTHOR]

An epithelium is important for integrity, homeostasis, communication and co-ordination, and its development must have been a fundamental step in the evolution of modern metazoan body plans. Sponges are metazoans that are often said to lack a true epithelium. We assess the properties of epithelia, and review the history of studies on sponge epithelia, focusing on their homology to bilaterian epithelia, their ultrastructure, and on their ability to seal. Electron micrographs show that adherens-type junctions are present in sponges but they can appear much slighter than equivalent junctions in other metazoans. Fine septae are seen in junctions of all sponge groups, but distinct septate junctions are only known from Calcarea. Similarly, all sponges can have collagenous sheets underlying their epithelia, but only homoscleromorphs are established to have a distinct basal lamina. The presence of most, but not all, gene families known to be involved in epithelial development and function also suggests that sponge epithelia function like, and are homologous to, bilaterian epithelia. However, physiological evidence that sponge epithelia regulate their internal environment is so far lacking. Given that up to six differentiated epithelia can be recognized in sponges, distinct physiological roles are expected. Recognition that sponges have epithelia challenges the perception that sponges are only loose associations of cells, and helps to relate the biology and physiology of the body plan of the adult sponge to the biology of other metazoans. [ABSTRACT FROM AUTHOR]

We investigated the capacity for phenotypic plasticity of skeletal muscle from Varanus exanthematicus, the savannah monitor lizard. Iliofibularis muscle from one leg of each lizard was electrically stimulated for 8 weeks. Both stimulated and contralateral control muscles were collected and processed for electron microscopy. We used stereological analysis of muscle cross-sections to quantify the volume densities of contractile elements, sarcoplasmic reticulum, mitochondria and intracellular lipids. We found that mitochondrial volume density was approximately fourfold higher in the stimulated muscle compared to controls, which were similar to previously reported values. Sarcoplasmic reticulum volume density was reduced by an amount similar to the increase in mitochondrial volume density while the volume density of contractile elements remained unchanged. Intracellular lipid accumulation was visibly apparent in many stimulated muscle sections but the volume density of lipids did not reach a significant difference. Although monitor lizards lack the highly developed aerobic metabolism of mammals, they appear to possess the capacity for muscle plasticity. [ABSTRACT FROM AUTHOR]

Abstract: Bis-chelated gold(I) phosphine complexes have shown great potential as anticancer agents, however, their efficacy has been limited by their high toxicity and lack of selectivity for cancer cells. Here, we have investigated the anticancer activity of a new bis-chelated Au(I) bidentate phosphine complex of the novel water soluble ligand 1,3-bis(di-2-pyridylphosphino)propane (d2pypp). We show that this gold complex [Au(d2pypp)2]Cl, at submicromolar concentrations, selectively induces apoptosis in breast cancer cells but not in normal breast cells. Apoptosis was induced via the mitochondrial pathway, which involved mitochondrial membrane potential depolarisation, depletion of the glutathione pool and caspase-3 and caspase-9 activation. The gold lipophilic complex was accumulated in mitochondria of cells, driven by the high mitochondrial membrane potential. To address the molecular basis of the observed selectivity between the two cell lines we investigated the effect of the gold complex on the thioredoxin/thioredoxin reductase system in normal and cancer breast cells. We show that [Au(d2pypp)2]Cl inhibits the activities of both thioredoxin and thioredoxin reductase and that this effect is more pronounced in the breast cancer cells. This difference may account for the selective cell death seen in the breast cancer cells but not in the normal cells. Our investigation has led to new insights into the mechanism of action of bis-chelated gold(I) diphosphine complexes and their future development as mitochondria targeted chemotherapeutics. [Copyright &y& Elsevier]

Many rDNA molecular phylogenetic studies result in trees that are incongruent to either alternative gene tree reconstructions and/or morphological assumptions. One reason for this outcome might be the application of suboptimal phylogenetic substitution models. While the most commonly implemented models describe the evolution of independently evolving characters fairly well, they do not account for character dependencies such as rRNA strands that form a helix in the ribosome. Such nonindependent sites require the use of models that take into account the coevolution of the complete nucleotide pair (doublet). We analyzed 28S rDNA (LSU) demosponge phylogenies using a “doublet” model for pairing sites (rRNA-helices) and compared our findings with the results of “standard” approaches using Bayes factors. We demonstrate that paired and unpaired sites of the same gene result in different reconstructions and that usage of a doublet model leads to more reliable demosponge trees. We show the influence of more sophisticated models on phylogenetic reconstructions of early-branching metazoans and the phylogenetic relationships of demosponge orders. [ABSTRACT FROM AUTHOR]

In stark contrast to the rapid morphological radiation of eumetazoans during the Cambrian explosion, the simple body plan of sponges (Phylum Porifera) emerged from the Cambrian relatively unchanged. Although the genetic and developmental underpinnings of these disparate evolutionary outcomes are unknown. comparisons between modern sponges and eumetazoans promise to reveal the extent to which critical genetic factors were present in their common ancestors. Two particularly interesting classes of genes in this respect are those involved in cell signaling and adhesion. These genes help guide development and morphogenesis in modern eumetazoans, but the timing and sequence of their origins is unknown. Here, we demonstrate that the sponge OscarelIa carmela, one of the earliest branching animals, expresses core components of the Wnt, transforming growth factor β, receptor tyrosine kinase, Notch, Hedgehog, and Jak/Stat signaling pathways. Furthermore, we identify sponge homologs of nearly every major eumetazoan cell-adhesion gene family, including those that encode cell-surface receptors, cytoplasmic linkers, and extracellular-matrix proteins. From these data, we infer that key signaling and adhesion genes were in place early in animal evolution, before the divergence of sponge and eumetazoan lineages. [ABSTRACT FROM AUTHOR]

Abstract: Very little is known about the dispersal of marine sponges but hypotheses based upon observations of larval life suggest limited dispersal ability. Until recently, the diversity of dispersal mechanisms employed by different species, coupled with the putative cosmopolitan distribution of some species, suggested that short larval life may not limit sponge dispersal. However, recent studies have found that “cosmopolitan species” frequently represent morphologically cryptic species complexes Here, the historical biogeography of the circum-tropical marine sponge genus Placospongia is investigated using sequence data from the internal transcribed spacer region (ITS). ITS is the predominant marker used for fine-scale investigations in sponges (and many other taxa), but problems with paralogy (divergent copies within individual genomes) have brought the utility of this marker into question. Ninety-eight ITS subclones were sequenced from twenty-eight individuals of Placospongia sampled from twelve localities worldwide. Divergent ITS paralogs were detected but the data still reflected geographic (and presumably phylogenetic) structure. Placospongia populations sampled were found to harbor at least 9 unique evolutionary lineages, several of which are sympatrically distributed but morphologically indistinguishable. Most of the relationships reconstructed are consistent with the hypothesis that marine sponges do not disperse very far (by any means). Nevertheless, phylogenetic divergences between lineages were not clearly consistent with modern, or historical, geological or oceanographic processes. No component of the phylogeny presented clearly reflected the geological event of the rising of this Isthmus of Panama and populations from marine lakes in Indonesia were found to be indistinguishable from populations in the Seychelles. These biogeographically anomalous results highlight that ITS is useful as a tool to identify interesting preliminary patterns in widespread groups, but that these patterns should be tested using multiple independent loci. [Copyright &y& Elsevier]

Abstract: Large subunit ribosomal DNA (LSU rDNA) sequence data from 120 taxa and cytochrome oxidase subunit 1(COI) sequence data from 27 taxa are analyzed separately and together to estimate the internal phylogeny of the class Demospongiae and to evaluate how consistent these data are with pre-existing hypotheses of relationship concerning order-level monophyly and relationships. The monophyly of Porifera is only slightly inconsistent with LSU data, which do not support the monophyly of the class Demospongiae regardless of the inclusion or exclusion of Homoscleromopha (this result is likely due to the placement of a single hexactinellid taxon within the Demospongiae), however, no LSU support is found for the monophyly of Silicea (Demospongiae+Hexactinellida) unless homoscleromorphs are excluded. Neither the subclasses Ceractinomorpha and Tetractinomorpha, nor the orders Halichondrida, Hadromerida, and Haplosclerida are supported as monophyletic under any data partition. The haplosclerid suborders Haplosclerina and Petrosina are supported as monophyletic to the exclusion of the suborder Spongillina, and the orders Dictyoceratida, Verongida, Poecilosclerida, Astrophorida, Spirophorida, Homosclerophorida, and Agelasida are largely reconstructed as monophyletic, with the exception of few anomalously placed taxa. Few inter-order relationships are strongly supported by any data partition, but there is moderate support for a verongid+chondrosid clade and a tetractinellid+halichondrid clade. Furthermore, LSU data strongly support the existence of two novel clades that do not correspond to the existing classification and that show no morphological uniformity. Finally, every data partition supports the monophyly of a clade that includes the order Agelasida, some members of the genus Axinella, and two taxa tentatively identified as belonging to the orders Hadromerida and Halichondrida. [Copyright &y& Elsevier]

The internal transcribed spacer regions (ITS1 and ITS2) of the tandemly repeated nuclear ribosomal DNA clusters are frequently used as markers for fine scale analyses in diverse animals. In certain taxa, ITS is nearly exclusively used for population level or inter-specific studies, despite the frequent presence of divergent paralogs within individual genomes that can be phylogenetically misleading. For the first time we survey diverse marine sponges to determine the extent and phylogenetic implications of intragenomic polymorphisms (IGPs) exhibited at their ITS loci. We discover that the extent of IGP varies greatly between taxa (with most taxa exhibiting very few) and cannot be predicted by taxonomy. Furthermore, we demonstrate that ITS can be phylogenetically informative between species when moderate levels of IGPs are detected, but that ITS paralogy can interfere with population level studies. We caution against the routine use of ITS in phylogenetic studies of sponges without (1) screening for IGPs in specimens from every population sampled; (2) including all divergent paralogs in phylogenetic analyses; (3) testing ITS data using other single-copy, unlinked loci (such as nuclear introns). [Copyright &y& Elsevier]

Two cDNA clones (ZmFRK1 and ZmFRK2) encoding fructokinases (FRKs, E.C. 2.7.1.4) were isolated from maize (Zea mays L.). They encode polypeptides of 323 and 335 amino acids, respectively. Both of the deduced proteins contain ATP binding motif and putative substrate recognition sequences. They share 73.7% sequence identity, and have high sequence homology with previously isolated FRKs from potato, sugar beet, tomato, and Arabidopsis. The in vitro enzymatic studies of the recombinant ZmFrk1 and ZmFrk2 proteins showed that they both had fructose specific kinase activities, but ZmFrk1 had much higher turnover rate than ZmFrk2. Both ZmFrk1 and ZmFrk2 were inhibited by the substrate fructose although ZmFrk1 was less sensitive. The mRNAs of both ZmFRK1 and ZmFRK2 accumulated to high levels in roots and stems, but were barely detectable in leaves. The expression pattern of the two genes was different during seed development. The transcript of ZmFRK1 only appeared in later stages of development, whereas the ZmFRK2 mRNA was expressed in earlier time. Taken together, our results imply that ZmFRK1 and ZmFRK2 play distinct biological roles during seed development. [Copyright &y& Elsevier]

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]

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]

Objective: Low and middle income countries of Africa account for a disproportionate amount of the global health burden of cancer. Providing patients access to psychosocial oncology and palliative care through policy structures such as the National Cancer Control Plans (NCCP) is essential to improving the care provided to patients and their families. The first phase of this study sought to determine the extent to which palliative care and psychosocial oncology were integrated in NCCPs in African countries. Methods: A qualitative thematic analysis of the plans was used using Nvivo, with two‐raters coding and continuous team discussions. Data were organized into an infographic map showing the coverage of themes across African countries. Results: Fifty‐eight NCCPs and NCD plans were analyzed in the 54 countries in Africa. The findings illustrate a lack of standardization across countries' NCCPs in addressing psychosocial oncology and palliative care themes. Certain areas presented good coverage across several plans, such as barriers to access, education, awareness, and health behaviors, coordination of care, families, caregivers and community involvement, and palliative care. Other themes presented low coverage, such as doctor‐patient communication, mental health, bereavement, psychosocial care, survivorship care, and traditional medicine. Conclusions: One may consider further developing NCCP areas as they pertain to psychosocial oncology and palliative care to ensure their proper place on the policy agenda for a healthier Africa. [ABSTRACT FROM AUTHOR]

Tosches et al. show that melatonin signaling regulates circadian swimming in annelid worms by rhythmically activating cholinergic neurons. This suggests an evolutionary connection between melatonin signaling in invertebrates and sleep regulation in vertebrates. [ABSTRACT FROM AUTHOR]

Presents information on the symposium "Sponges: New Views of Old Animals," which highlighted diverse aspects of poriferan biology. Description of sponges; Relevance of sponges to studies of animal evolution; Importance of the study of sponge embryogenesis to a person's understanding of early animals; Overview of the ecology of sponges that border Antarctica.

A grass-fire cycle in Australian tropical savannas has been postulated as driving the regional decline of the obligate-seeding conifer Callitris intratropica and other fire-sensitive components of the regional flora and fauna, due to proliferation of flammable native grasses. We tested the hypothesis that a high-biomass invasive savanna grass drives a positive feedback process where intense fires destroy fire-sensitive trees, and the reduction in canopy cover facilitates further invasion by grass. We undertook an observational and experimental study using, as a model system, a plantation of C. intratropica that has been invaded by an African grass, gamba (Andropogon gayanus) in the Northern Territory, Australia. We found that high grass biomass was associated with reduced canopy cover and restriction of foliage to the upper canopy of surviving stems, and mortality of adult trees was very high (>50%) even in areas with low fuel loads (1 t.ha -1). Experimental fires, with fuel loads >10 t.ha -1, typical of the grass-invasion front, caused significant mortality due to complete crown scorch. Lower fuel loads cause reduced canopy cover through defoliation of the lower canopy. These results help explain how increases in grass biomass are coupled with the decline of C. intratropica throughout northern Australia by causing a switch from litter and sparse perennial grass fuels, and hence low-intensity surface fires, to heavy annual grass fuel loads that sustain fires that burn into the midstorey. This study demonstrates that changes in fuel type can alter fire regimes with substantial knock-on effects on the biota. [ABSTRACT FROM AUTHOR]

Motivated by the urgent need to understand how water stress-induced embolism limits the survival and recovery of plants during drought, the linkage between water-stress tolerance and xylem cavitation resistance was examined in one of the world's most drought resistant conifer genera, Callitris., Four species were subjected to drought treatments of −5, −8 and −10 MPa for a period of 3-4 wk, after which plants were rewatered. Transpiration, basal growth and leaf water potential were monitored during and after drought., Lethal water potential was correlated with the tension producing a 50% loss of stem hydraulic conductivity. The most resilient species suffered minimal embolism and recovered gas exchange within days of rewatering from −10 MPa, while the most sensitive species suffered major embolism and recovered very slowly. The rate of repair of water transport in the latter case was equal to the rate of basal area growth, indicating xylem reiteration as the primary means of hydraulic repair., The survival of, and recovery from, water stress in Callitris are accurately predicted by the physiology of the stem water-transport system. As the only apparent means of xylem repair after embolism, basal area growth is a critical part of this equation. [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. [ABSTRACT FROM AUTHOR]

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. [ABSTRACT FROM AUTHOR]

Abstract: The goal of this study was to determine if there is a difference in the achieved depth of sedation, the rate of respiratory depression, procedural difficulty, or patient perceived pain or recall between patients randomized to a pre-procedural target sedation level of moderate or deep procedural sedation using propofol during the reduction of fractures and dislocations in the Emergency Department (ED). This was a randomized, prospective study of adults undergoing procedural sedation (PS) with propofol for fracture or dislocation reduction in the ED between July 2003 and March 2004. Patients were randomized to a target sedation level of moderate or deep, using American Society of Anesthesiologists’ definitions. Doses, vital signs, nasal end tidal CO2 (ETCO2), pulse oximetry, and bispectral EEG analysis (BIS) scores were recorded. Respiratory depression was defined as a change in ETCO2 >10, an oxygen saturation of <90% at any time, or an absent ETCO2 waveform at any time. After the procedure, patients were asked if they perceived any pain or had any recall of the procedure. Physicians were asked to rate the difficulty of completing the reduction using a 100-mm visual analog scale (VAS). Respiratory depression rates were compared with chi-square tests, BIS and VAS scores were compared with t tests. Seventy-five patients were enrolled, 39 randomized to the target of moderate PS and 36 to the target of deep PS. No significant complications were noted. There were 25/36 (69%) of the patients assigned to the deep sedation target group who actually achieved a deep level of sedation and 21/39 (54%) of the patients assigned to the moderate sedation target group who actually achieved a moderate level of sedation (p = 0.40). Respiratory depression was seen in 19/39 (49%) patients with the moderate PS target and 18/36 (50%) with the deep PS target (p = 0.91). The mean minimum recorded BIS score was 67.7 (95% confidence interval [CI] 62.2–73.3) for the moderate PS target group and 59.2 (95% CI 55.1–64.2) for the deep PS target group (p = 0.03). There were 12/39 (31%) in the moderate PS target group and 4/36 (11%) in the deep PS target group who reported pain with or recall of the procedure (p = 0.04). The mean physician VAS for procedural difficulty was 34.0 (95% CI 23.7–44.3) for the moderate PS group and 28.8 (95% CI 18.4–39.2) for the deep PS group (p = 0.46). In this study, the assignment of a pre-procedural target sedation level of moderate or deep PS did not influence the level of sedation achieved, the rate of respiratory depression, the occurrence of complications, the time to return of baseline mental status, or the success of the procedure. It does not seem that the assignment of a pre-procedural target sedation level is an effective means of changing the outcome of ED PS. [Copyright &y& Elsevier]

A cDNA clone from a 4 DAP dissected maize embryo sac encoding a novel Zea mays single‐repeat Myb protein is reported here. This full‐length cDNA contains an ORF of 948 bp. The gene ZmMybst1 contains two introns (1166 and 706 bp) and is a single copy gene. The ZmMybst1 protein shares high sequence identity with the potato Mybst1 protein (58%). Northern blot, RT‐PCR and electronic northern analysis shows that ZmMybst1 is expressed in endosperm between 4 and 30 DAP, coinciding with the period of aleurone cell differentiation and development. [ABSTRACT FROM PUBLISHER]

The ecology of the Australian monsoon tropics is fundamentally shaped by dry conditions between May and October followed by highly variable rainfall over the months of November to April. Due to its crucial ecological importance, a better understanding of past hydroclimate variability in the region is of great interest to land managers and custodians in this region. Short instrumental records also make highly resolved terrestrial palaeoclimate records for northern Australia prior to 1900 CE of considerable scientific importance. Here, we present two new well‐replicated Callitris intratropica ring‐width chronologies from Arnhem Land in northern Australia, one of which extends the tree‐ring record in the region by another 86 years, back to 1761. Both chronologies have clearly defined regional patterns of correlations with temperature, precipitation, potential evapotranspiration and two drought indices (the self‐calibrating Palmer Drought Severity Index (PDSI) and the Standardised Precipitation Evapotranspiration Index (SPEI)) across the lower latitudes of the Northern Territory. Results indicate considerable scope for hydroclimatic reconstructions based on C. intratropica for transitional periods into and out of the wettest time of the year. This suggests that such reconstructions would reflect variability in the duration of the wet period. While precipitation or streamflow reconstructions may be possible for both these transitional periods, drought reconstructions will be best focused on the months of March–May at the end of the wet period. Hydroclimate reconstructions would provide important baseline information for understanding the rate and magnitude of current regional climate change for these ecologically and culturally important transitional periods. [ABSTRACT FROM AUTHOR]

The article offers information on concept of having mentors for elementary students. It mentions about school-based mentoring programs often recruit community members as volunteer mentors and tutors for students; and also focuses on aim of peer-mentoring to provides an opportunity for educators to leverage the expertise of high school students participating in STEM programs of study to provide mentorship and guidance.

The evolution of cell-adhesion mechanisms in animals facilitated the assembly of organized multicellular tissues. Studies in traditional animal models have revealed two predominant adhesion structures, the adherens junction (AJ) and focal adhesions (FAs), which are involved in the attachment of neighboring cells to each other and to the secreted extracellular matrix (ECM), respectively. The AJ (containing cadherins and catenins) and FAs (comprising integrins, talin, and paxillin) differ in protein composition, but both junctions contain the actin-binding protein vinculin. The near ubiquity of these structures in animals suggests that AJ and FAs evolved early, possibly coincident with multicellularity. However, a challenge to this perspective is that previous studies of sponges--a divergent animal lineage--indicate that their tissues are organized primarily by an alternative, sponge-specific cell-adhesion mechanism called "aggregation factor." In this study, we examined the structure, biochemical properties, and tissue localization of a vinculin ortholog in the sponge Oscarella pearsei (Op). Our results indicate that Op vinculin localizes to both cell-cell and cell-ECM contacts and has biochemical and structural properties similar to those of vertebrate vinculin. We propose that Op vinculin played a role in cell adhesion and tissue organization in the last common ancestor of sponges and other animals. These findings provide compelling evidence that sponge tissues are indeed organized like epithelia in other animals and support the notion that AJ- and FA-like structures extend to the earliest periods of animal evolution. [ABSTRACT FROM AUTHOR]

The homoscleromorph sponge Oscarella carmela, first described from central California, USA is shown to represent two superficially similar but both morphologically and phylogenetically distinct species that are co-distributed. We here describe a new species as Oscarella pearsei, sp. nov. and re-describe Oscarella carmela; the original description was based upon material from both species. Further, we correct the identification of published genomic/transcriptomic resources that were originally attributed to O. carmela, and present new Illumina-sequenced transcriptome assemblies for each of these species, and the mitochondrial genome sequence for O. pearsei sp. nov. Using SSU and LSU ribosomal DNA and the mitochondrial genome, we report the phylogenetic relationships of these species relative to other Oscarella species, and find strong support for the placement of O. pearsei sp. nov. in a distinct clade within genus Oscarella defined by the presence of spherulous cells that contain paracrystalline inclusions; O. carmela lacks this cell type. Oscarella pearsei sp. nov and O. carmela can be tentatively distinguished based upon gross morphological differences such as color, surface texture and extent of mucus production, but can be more reliably identified using mitochondrial and nuclear barcode sequencing, ultrastructural characteristics of cells in the mesohyl, and the morphology of the follicle epithelium which surrounds the developing embryo in reproductively active individuals. [ABSTRACT FROM AUTHOR]

Highlights: [•] Large monomeric proteins suffer from spectral crowding. [•] Nonuniform sampling of 3D and 4D data optimizes spectral resolution. [•] Selective methyl labeling and tailored NMR experiments provide distance constraints. [•] Large multimeric proteins are studied with divide and conquer approach. [•] Multimeric proteins are studied by combining NMR methods with other techniques. [Copyright &y& Elsevier]

Abstract: Despite clear evidence that polymeric nitric oxide (NO) release coatings reduce the foreign body response (FBR) and may thus improve the analytical performance of in vivo continuous glucose monitoring devices when used as sensor membranes, the compatibility of the NO release chemistry with that required for enzymatic glucose sensing remains unclear. Herein, we describe the fabrication and characterization of NO-releasing polyurethane sensor membranes using NO donor-modified silica vehicles embedded within the polymer. In addition to demonstrating tunable NO release as a function of the NO donor silica scaffold and polymer compositions and concentrations, we describe the impact of the NO release vehicle and its release kinetics on glucose sensor performance. [Copyright &y& Elsevier]

Abstract: It has been posited that animal development evolved from pre-existing mechanisms for regulating cell differentiation in the single celled and colonial ancestors of animals. Although the progenitors of animals cannot be studied directly, insights into their cell biology may be gleaned from comparisons between animals and their closest living relatives, the choanoflagellates. We report here on the life history, cell differentiation and intercellular interactions in the colony-forming choanoflagellate Salpingoeca rosetta. In response to diverse environmental cues, S. rosetta differentiates into at least five distinct cell types, including three solitary cell types (slow swimmers, fast swimmers, and thecate cells) and two colonial forms (rosettes and chains). Electron microscopy reveals that cells within colonies are held together by a combination of fine intercellular bridges, a shared extracellular matrix, and filopodia. In addition, we have discovered that the carbohydrate-binding protein wheat germ agglutinin specifically stains colonies and the slow swimmers from which they form, showing that molecular differentiation precedes multicellular development. Together, these results help establish S. rosetta as a model system for studying simple multicellularity in choanoflagellates and provide an experimental framework for investigating the origin of animal multicellularity and development. [Copyright &y& Elsevier]

Cnidaria have traditionally been viewed as the most basal animals with complex, organ-like multicellular structures dedicated to sensory perception. However, sponges also have a surprising range of the genes required for sensory and neural functions in Bilateria. Here, we: (1) discuss "sense organ" regulatory genes, including; sine oculis, Brain 3, and eyes absent, that are expressed in cnidarian sense organs; (2) assess the sensory features of the planula, polyp, and medusa life-history stages of Cnidaria; and (3) discuss physiological and molecular data that suggest sensory and "neural" processes in sponges. We then develop arguments explaining the shared aspects of developmental regulation across sense organs and between sense organs and other structures. We focus on explanations involving divergent evolution from a common ancestral condition. In Bilateria, distinct sense-organ types share components of developmental-gene regulation. These regulators are also present in basal metazoans, suggesting evolution of multiple bilaterian organs from fewer antecedent sensory structures in a metazoan ancestor. More broadly, we hypothesize that developmental genetic similarities between sense organs and appendages may reflect descent from closely associated structures, or a composite organ, in the common ancestor of Cnidaria and Bilateria, and we argue that such similarities between bilaterian sense organs and kidneys may derive from a multifunctional aggregations of choanocyte-like cells in a metazoan ancestor. We hope these speculative arguments presented here will stimulate further discussion of these and related questions. [ABSTRACT FROM AUTHOR]

In search of maize MADS-box genes expressed during kernel development we identified two cDNA’s corresponding to the AGL2 MADS-box gene subfamily members ZMM6 and ZMM27. Expression analyses show that expression is restricted to developing infloresences and developing kernels. In kernels the accumulation of both transcripts increase after pollination, indicating that they play a role during kernel development. In situ hybridization revealed that ZMM27 is expressed in both maternal and zygotic kernel tissues, whereas ZMM6 expression becomes restricted to the endosperm transfer cell region and the embryo as the grain develops. In an attempt to elucidate the role of MADS-box genes expressed during maize kernel development, we identified Mutator-insertion loss-of-function alleles for both ZMM6 and ZMM27 using reverse genetics. Analyses of plants homozygous for the mutant allele of ZMM6 or ZMM27, as well as double homozygous mutants showed no obvious developmental defects in the kernel, suggesting the presence of additional members of the AGL2 clade in maize with functional redundancy with of ZMM6 or ZMM27. [Copyright &y& Elsevier]

Genes for the enzymes that make plant cell wall hemicellulosic polysaccharides remain to be identified. We report here the isolation of a complementary DMA (cDNA) clone encoding one such enzyme, mannan synthase (ManS), that makes the β-1, 4-mannan backbone of galactomannan, a hemicellulosic storage polysaccharide in guar seed endosperm walls. The soybean somatic embryos expressing ManS cDNA contained high levels of ManS activities that localized to Colgi. Phylogenetically, ManS is closest to group A of the cellulose synthase-like (Csl) sequences from Arabidopsis and rice. Our results provide the biochemical proof for the involvement of the Csl genes in β-glycan formation in plants. [ABSTRACT FROM AUTHOR]

Examines the defective kernel 1 (dek1) gene for aleurone cell development in the endosperm of maize grains endoces. Specification of maize aleurone cell; Activation of tumor necrosis factor receptor; Isolation of dek1 for transcription and sequencing.