Specific Heat of the Dilute Ising Magnet LiHox_xY1−x_{1-x}F4_4

We present specific heat data on three samples of the dilute Ising magnet \HoYLF with $x = 0.018$, 0.045 and 0.080. Previous measurements of the ac susceptibility of an $x = 0.045$ sample showed the Ho$^{3+}$ moments to remain dynamic down to very low temperatures and the specific heat was found to have unusually sharp features. In contrast, our measurements do not exhibit these sharp features in the specific heat and instead show a broad feature, for all three samples studied, which is qualitatively consistent with a spin glass state. Integrating $C/T$, however, reveals an increase in residual entropy with lower Ho concentration, consistent with recent Monte Carlo simulations showing a lack of spin glass transition for low x.Comment: 10 pages, 3 figurs, accepted for publication in Phys. Rev. Let

General practice placements for pre-registration junior doctors: adding value to intern education and training

The document attached has been archived with permission from the editor of the Medical Journal of Australia (6 May 2008). An external link to the publisher’s copy is includedObjective: To examine pre-registration junior doctors’ perceptions of the value of a general practice term in their training program. Design, setting and participants: Semi-structured interviews, in five teaching hospitals in South Australia in 2005, with 20 pre-registration junior doctors (interns) who had completed a general practice term and at least one core term of intern training. Main outcome measure: Comparisons between general practice and teaching hospital core training terms with respect to the domains of junior doctor education. Results: Interns perceived general practice and teaching hospital terms to be complementary in their overall training program. The general practice term provided them with knowledge and skills they would not have acquired in the teaching hospital terms alone. One-on-one consulting, initiating patient management, and the opportunity to practise a range of practical and procedural skills were seen to be of particular value. Conclusions: The general practice and teaching hospital terms both contribute to the training of interns, offering contrasting environments and experiences which enhance interns’ professional and personal growth. General practice terms should be considered for inclusion in intern training programs across Australia.Anne A Martin, Caroline O Laurence, Linda E Black and Bruce V Mugfor

An aphid RNA transcript migrates systemically within plants and is a virulence factor

Aphids are sap-feeding insects that colonize a broad range of plant species and often cause feeding damage and transmit plant pathogens, including bacteria, viruses, and viroids. These insects feed from the plant vascular tissue, predominantly the phloem. However, it remains largely unknown how aphids, and other sap-feeding insects, establish intimate long-term interactions with plants. To identify aphid virulence factors, we took advantage of the ability of the green peach aphid Myzus persicae to colonize divergent plant species. We found that a M. persicae clone of near-identical females established stable colonies on nine plant species of five representative plant eudicot and monocot families that span the angiosperm phylogeny. Members of the novel aphid gene family Ya are differentially expressed in aphids on the nine plant species and are coregulated and organized as tandem repeats in aphid genomes. Aphids translocate Ya transcripts into plants, and some transcripts migrate to distal leaves within several plant species. RNAi-mediated knockdown of Ya genes reduces M. persicae fecundity, and M. persicae produces more progeny on transgenic plants that heterologously produce one of the systemically migrating Ya transcripts as a long noncoding (lnc) RNA. Taken together, our findings show that beyond a range of pathogens, M. persicae aphids translocate their own transcripts into plants, including a Ya lncRNA that migrates to distal locations within plants, promotes aphid fecundity, and is a member of a previously undescribed host-responsive aphid gene family that operate as virulence factors

Economics methods in Cochrane systematic reviews of health promotion and public health related interventions.

Peer reviewedPublisher PD

Hybridisation has shaped a recent radiation of grass-feeding aphids

Background: Aphids are common crop pests. These insects reproduce by facultative parthenogenesis involving several rounds of clonal reproduction interspersed with an occasional sexual cycle. Furthermore, clonal aphids give birth to live young that are already pregnant. These qualities enable rapid population growth and have facilitated the colonisation of crops globally. In several cases, so-called “super clones” have come to dominate agricultural systems. However, the extent to which the sexual stage of the aphid life cycle has shaped global pest populations has remained unclear, as have the origins of successful lineages. Here, we used chromosome-scale genome assemblies to disentangle the evolution of two global pests of cereals—the English (Sitobion avenae) and Indian (Sitobion miscanthi) grain aphids.   Results: Genome-wide divergence between S. avenae and S. miscanthi is low. Moreover, comparison of haplotype-resolved assemblies revealed that the S. miscanthi isolate used for genome sequencing is likely a hybrid, with one of its diploid genome copies closely related to S. avenae (~ 0.5% divergence) and the other substantially more divergent (> 1%). Population genomics analyses of UK and China grain aphids showed that S. avenae and S. miscanthi are part of a cryptic species complex with many highly differentiated lineages that predate the origins of agriculture. The complex consists of hybrid lineages that display a tangled history of hybridisation and genetic introgression.   Conclusions: Our analyses reveal that hybridisation has substantially contributed to grain aphid diversity, and hence, to the evolutionary potential of this important pest species. Furthermore, we propose that aphids are particularly well placed to exploit hybridisation events via the rapid propagation of live-born “frozen hybrids” via asexual reproduction, increasing the likelihood of hybrid lineage formation

An early career perspective on encouraging collaborative and interdisciplinary research in ecology

There is a growing need for collaborative and interdisciplinary research in addressing global ecological challenges, and early career researchers (ECRs) often play a vital role in such ventures. But despite the desire for such approaches, forming new and interdisciplinary collaborations is risky, and disproportionately so for ECRs, whose perspectives on this topic are rarely heard. Here, we present common perceptions among ECRs regarding opportunities for intra- and interdisciplinary collaboration, and barriers preventing such collaboration from taking place. We also discuss possible solutions, and the ecological outcomes of fostering more collaboration. The perceptions discussed have been distilled from a two-day workshop in New Zealand, aiming to investigate the potential for collaboration between 34 ECRs in distinct ecological disciplines across ten research institutes. Commonality in methodology or research aims was vital for potential collaborations to be considered worthwhile, but differences in spatial or temporal scales were a key disconnect that hindered numerous potential crossovers. Individual connectivity and institutional structures were commonly perceived as barriers to acting collaboratively in general. Specifically, barriers included having a small peer network, lack of access to funding, and concerns over the risk/reward ratio of forming new collaborations. Overcoming barriers will require active, practical support from institutions, funding bodies and mentors, and participants commonly called for specific funding support and the creation of ECR-focused spaces to better foster collaborative behavior. Fostering interdisciplinary ECR collaborations in ecology was perceived to be useful in creating larger and more useful datasets and tools, and more scalable and transferable models and outcomes. Adopting practices that facilitate more ECR-led interdisciplinary collaboration will help generate a more integrative understanding of ecological systems globally

Sex-specific changes in the aphid DNA methylation landscape

Aphids present an ideal system to study epigenetics as they can produce diverse, but genetically identical, morphs in response to environmental stimuli. Here, using whole genome bisulphite sequencing and transcriptome sequencing of the green peach aphid (Myzus persicae), we present the first detailed analysis of cytosine methylation in an aphid and investigate differences in the methylation and transcriptional landscapes of male and asexual female morphs. We find that methylation primarily occurs in a CG dinucleotide (CpG) context and that exons are highly enriched for methylated CpGs, particularly at the 3' end of genes. Methylation is positively associated with gene expression, and methylated genes are more stably expressed than un-methylated genes. Male and asexual female morphs have distinct methylation profiles. Strikingly, these profiles are divergent between the sex chromosome and the autosomes; autosomal genes are hypo-methylated in males compared to asexual females, whereas genes belonging to the sex chromosome, which is haploid in males, are hyper-methylated. Overall, we find correlated changes in methylation and gene expression between males and asexual females, and this correlation is particularly strong for genes located on the sex chromosome. Our results suggest that differential methylation of sex-biased genes plays a role in aphid sexual differentiation

Hox10 Genes Function in Kidney Development in the Differentiation and Integration of the Cortical Stroma

Organogenesis requires the differentiation and integration of distinct populations of cells to form a functional organ. In the kidney, reciprocal interactions between the ureter and the nephrogenic mesenchyme are required for organ formation. Additionally, the differentiation and integration of stromal cells are also necessary for the proper development of this organ. Much remains to be understood regarding the origin of cortical stromal cells and the pathways involved in their formation and function. By generating triple mutants in the Hox10 paralogous group genes, we demonstrate that Hox10 genes play a critical role in the developing kidney. Careful examination of control kidneys show that Foxd1-expressing stromal precursor cells are first observed in a cap-like pattern anterior to the metanephric mesenchyme and these cells subsequently integrate posteriorly into the kidney periphery as development proceeds. While the initial cap-like pattern of Foxd1-expressing cortical stromal cells is unaffected in Hox10 mutants, these cells fail to become properly integrated into the kidney, and do not differentiate to form the kidney capsule. Consistent with loss of cortical stromal cell function, Hox10 mutant kidneys display reduced and aberrant ureter branching, decreased nephrogenesis. These data therefore provide critical novel insights into the cellular and genetic mechanisms governing cortical cell development during kidney organogenesis. These results, combined with previous evidence demonstrating that Hox11 genes are necessary for patterning the metanephric mesenchyme, support a model whereby distinct populations in the nephrogenic cord are regulated by unique Hox codes, and that differential Hox function along the AP axis of the nephrogenic cord is critical for the differentiation and integration of these cell types during kidney organogenesis

Toxicogenomic Analysis Suggests Chemical-Induced Sexual Dimorphism in the Expression of Metabolic Genes in Zebrafish Liver

10.1371/journal.pone.0051971PLoS ONE712

Psycho-educational interventions for adults with severe or difficult asthma: a systematic review.

types: Journal Article; Research Support, Non-U.S. Gov't; ReviewThis is the author's version of the work that was accepted for publication in the Journal of Asthma. The final version can be accessed via the DOI in this record.Research highlights psychosocial factors associated with adverse asthma events. This systematic review therefore examined whether psycho-educational interventions improve health and self-management outcomes in adults with severe or difficult asthma. Seventeen controlled studies were included. Characteristics and content of interventions varied even within broad types. Study quality was generally poor and several studies were small. Any positive effects observed from qualitative and quantitative syntheses were mainly short term and, in planned subgroup analyses (involving < 5 trials), effects on hospitalizations, quality of life, and psychological morbidity in patients with severe asthma did not extend to those in whom multiple factors complicate management.UK NHS Health Technology Assessment Programm