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Aflatoxins are carcinogenic mycotoxins produced by

Information on the transcriptomic changes that occur within sclerotia of

Introduction Enabling education programs, otherwise known as Foundation Studies or Preparatory programs, provide pathways for students typically under-represented in higher education. Students in Enabling programs often face distinct challenges in their induction to academic culture which can implicate them in cases of misconduct. This case study addresses a gap in the enabling literature reporting on how a culture of academic integrity can be developed for students and staff in these programs through an educative approach. Case description This paper outlines how an educative approach to academic integrity is implemented within the Enabling programs of two Australian universities. Discussion and reflection This case study reflects upon an approach which makes specific reference to the key elements of ‘support’, ‘approach’ and ‘responsibility’ as highlighted in Bretag and Mahmud’s seminal paper. The paper reports a reduction in misconduct cases at the two institutions suggesting a positive correlation between the interventions and students’ understanding of ethical academic practice. This study reflects upon practitioner experiences with academic integrity investigations to evaluate the effectiveness of this approach. Conclusions The authors show that it is possible to ensure academic integrity practices and values are upheld within a supportive learning environment appropriate to a students’ level of study.

This article discusses the use of drama as a method for teaching and learning using two case studies from different geographical locations and teaching contexts in Australia. The first, from the University of Newcastle, is in the field of enabling education that supports students to gain the knowledge and skills required to continue their journey to a higher education degree. The other, from an existing university pre-service teaching programme at the University of Melbourne, supports students to gain the knowledge and skills required to enter the teaching profession in an Australian context. Both case studies, which are also part of a broader, ongoing research project, examine the role drama can play in the creation of supportive dialogical spaces for learning in higher education contexts, where the students come from a diverse range of socio-cultural backgrounds. The qualitative research is framed by practitioner research, pedagogical methodology and ethnodrama. Dramatized dialogue is used to share our findings. To date, our research has revealed that drama education techniques and activities, and the use of ethnodrama, can both enhance student participation and engagement, and contribute to successfully achieving the aims and objectives of the respective programmes.

The fungus Aspergillus flavus is an opportunistic crop pathogen that produces aflatoxins. Aflatoxins are potent carcinogenic and hepatotoxic secondary metabolites that are highly regulated in most countries. A. flavus also produces many other secondary metabolites and harbours more than 50 putative secondary metabolite biosynthetic gene clusters that have yet to be characterised. Bioactive secondary metabolites that augment the ability of the fungus to infect crops are of particular interest. Biosynthetic gene cluster 11 in A. flavus has been recently shown to encode for the biosynthesis of aspergillic acid, a toxic hydroxamic acid-containing pyrazinone compound that can bind iron, resulting in a red-orange pigment known as ferriaspergillin. A decrease in A. flavus pathogenicity and aflatoxin contamination was observed when aspergillic acid biosynthesis was blocked during maize seed infection. In this study, we probe the available genomes of Aspergillus species for biosynthetic gene cluster 11 homologs. We find that all species possessing gene cluster 11 produce aspergillic acid or a closely related isomer. We demonstrate that the Aspergillus section Flavi species harbouring biosynthetic gene cluster 11 produce a mixture of aspergillic acid, hydroxyaspergillic acid, and aspergillic acid analogs differing only in the amino acid precursors. Interestingly, many Aspergillus section Circumdati species, known mainly for their production of the problematic mycotoxin ochratoxin A, also harbour gene cluster 11 homologs, but do not produce aspergillic acid. Instead, these species produce neoaspergillic acid and its hydroxylated analog neohydroxyaspergillic acid, indicating that cluster 11 is responsible for neoaspergillic acid biosynthesis in Aspergillus section Circumdati.

BACKGROUND A measure of episode spending, such as Medicare Spending Per Beneficiary (MSPB) is increasingly used to evaluate provider performance. Yet if the measure is unreliable, as is often true for low-volume providers, it cannot distinguish "good" from "poor" performance. OBJECTIVE The objective of this study was to evaluate the reliability of a uniformly calculated MSPB measure for post-acute care (PAC) and the tradeoffs involved in setting a minimum case count threshold. DATA Medicare claims for 15 million PAC episodes from April 2013 to March 2015. RESEARCH DESIGN Given the overlap in patients treated in PAC settings, we developed a uniformly calculated MSPB measure for PAC providers that measures spending during the PAC stay and the following 30 days. We examine variation in the MSPB-PAC measure and characterize the measure's reliability and its relationship to provider case counts. RESULTS Applied to our MSPB-PAC measure, a minimum threshold of 20 Medicare episodes as currently used by the Centers for Medicare & Medicaid Services (CMS) would not establish reasonably reliable measures and could result in drawing unduly erroneous conclusions about provider performance. The measures for home health agencies were considerably less stable and reliable than for institutional PAC providers. CONCLUSIONS CMS should consider adopting a more stringent reliability standard for setting minimum case counts for MSPB-PAC and other measures. Its current threshold (R-statistic=0.4) reflects more random variation than differences in actual provider performance. To include as many providers as possible, CMS should consider pooling data over multiple years to avoid drawing incorrect conclusions about low-volume providers.

Aspergillus flavus infects several food and feed crops, such as corn (Zea mays L.), cotton (Gossypium hirsutum L.), peanuts (Arachis hypogaea L.), and tree nut crops and contaminates the seed with carcinogenic aflatoxins. These susceptible crops contain rich reserves of lipids and fatty acids. The nature of relationship between lipids and the ability of the fungus to infect and produce aflatoxins in mature cottonseed, a protein-rich animal feed, has been addressed previously. In this study, we tracked lipid accumulation in developing cottonseed (15–35 days post-anthesis [DPA]) and also the ability of an aflatoxigenic strain and an isogenic non-aflatoxigenic strain to grow and produce aflatoxins in planta. The aflatoxigenic strain Af-70 green fluorescent protein (GFP) and the isogenic, non-aflatoxigenic strain SRRC 1500 (fungal collections maintained at the Southern Regional Research Center) did not differ much in infection and colonization of cottonseed. The non-aflatoxigenic strain did not produc...

Provocations stimulate, goad, probe, prod, egg people on, unleash and entice. The aptly titled “Provocations of Practice’ does this and so much more. The pages are flowing with rich, layered, excit...

Edwin Wong begins the preface of his work with these words, ‘Tragedy today is a tired art. It no longer earns the attention and publicity that it did in previous ages’. In this book, Wong presents ...

The aim of this article is to provide primary teachers with effective ways of engaging in drama processes to affirm diversity and to promote inclusive education in regard to cultural and linguistic diversity. It is informed by, and a response to, the ‘cultural and linguistic’ section within the recently revised version of the Drama Australia Equity and Diversity Guidelines to which both authors contributed. It examines some ways in which recommendations and advice provided within the document can be enacted in primary schools through the use of drama education methods, in particular dramatic storytelling and process drama. Through their work the authors have found that drama techniques and processes can be highly effective in developing understandings of cultural and linguistic diversity within primary schools. By way of illustration this paper also focuses on the findings of a recent PhD project conducted by one of the authors, which focused on the education of pre-service primary teachers in the...

Aspergillus flavus is a soil-borne saprophyte and an opportunistic pathogen of both humans and plants. This fungus not only causes disease in important food and feed crops such as maize, peanut, cottonseed, and tree nuts but also produces the toxic and carcinogenic secondary metabolites (SMs) known as aflatoxins. Polyamines (PAs) are ubiquitous polycations that influence normal growth, development, and stress responses in living organisms and have been shown to play a significant role in fungal pathogenesis. Biosynthesis of spermidine (Spd) is critical for cell growth as it is required for hypusination-mediated activation of eukaryotic translation initiation factor 5A (eIF5A), and other biochemical functions. The tri-amine Spd is synthesized from the diamine putrescine (Put) by the enzyme spermidine synthase (Spds). Inactivation of spds resulted in a total loss of growth and sporulation in vitro which could be partially restored by addition of exogenous Spd. Complementation of the Δspds mutant with a wild type (WT) A. flavus spds gene restored the WT phenotype. In WT A. flavus, exogenous supply of Spd (in vitro) significantly increased the production of sclerotia and SMs. Infection of maize kernels with the Δspds mutant resulted in a significant reduction in fungal growth, sporulation, and aflatoxin production compared to controls. Quantitative PCR of Δspds mutant infected seeds showed down-regulation of aflatoxin biosynthetic genes in the mutant compared to WT A. flavus infected seeds. Expression analyses of PA metabolism/transport genes during A. flavus-maize interaction showed significant increase in the expression of arginine decarboxylase (Adc) and S-adenosylmethionine decarboxylase (Samdc) genes in the maize host and PA uptake transporters in the fungus. The results presented here demonstrate that Spd biosynthesis is critical for normal development and pathogenesis of A. flavus and pre-treatment of a Δspds mutant with Spd or Spd uptake from the host plant, are insufficient to restore WT levels of pathogenesis and aflatoxin production during seed infection. The data presented here suggest that future studies targeting spermidine biosynthesis in A. flavus, using RNA interference-based host-induced gene silencing approaches, may be an effective strategy to reduce aflatoxin contamination in maize and possibly in other susceptible crops.

Recent molecular phylogenetic studies have revealed the existence of at least 50 species of Morchella worldwide and demonstrated a high degree of continental endemism within the genus. Here we describe 19 phylogenetic species of Morchella from North America, 14 of which are new (M. diminutiva, M. virginiana, M. esculentoides, M. prava, M. cryptica, M. frustrata, M. populiphila, M. sextelata, M. septimelata, M. capitata, M. importuna, M. snyderi, M. brunnea and M. septentrionalis). Existing species names (M. rufobrunnea, M. tomentosa, M. punctipes and M. angusticeps) are applied to four phylogenetic species, and formal description of one species (M. sp. "Mel-8") is deferred pending study of additional material. Methods for assessing morphological features in Morchella are delineated, and a key to the known phylogenetic species of Morchella in North America is provided. Type studies of M. crassistipa, M. hotsonii, M. angusticeps and M. punctipes are provided. Morchella crassistipa is designated nomen dubium.

Tumor growth depends upon access to host blood vessels. Many steps in tumor angiogenesis have been defined including tumor cell hypoxia, tumor cell secretion of pro-angiogenic growth factors, receptor activation on host endothelium and stroma, and establishment of new blood vessels feeding the tumor mass. Inhibitors for some of these steps have been synthesized and tested clinically. While modest improvements in response, progression-free survival and overall survival have been observed in metastatic colorectal carcinoma, non-small cell lung carcinoma, breast carcinoma, renal cell carcinoma, and glioblastoma, almost all patients ultimately relapse and die from metastatic disease. Explanations for the limited effects of anti-angiogenesis therapy include lack of activity on all the parallel angiogenic pathways, non-specific toxicities of some of the agents, induction of a pro-metastatic phenotype by the enhanced hypoxia from therapy, and lack of effect on already established tumor blood vessels. One solution is to directly attack the tumor vasculature rather than inhibit tumor vessel formation. The flavonoid ASA404 and the tubulin-binder combretastatin A-4 phosphate directly damage tumor endothelium by different mechanisms. Both compounds have shown minimal single agent disease activity and produce cardiac ischemia in clinical trials. Recently, ligand-directed vascular disrupting agents have been synthesized and tested. A promising member of this class of therapeutics targets the tumor endothelial marker-8 (TEM8). Anti-TEM8 antibody drug conjugate may facilitate selective destruction of tumor blood vessels yielding enhanced anti-cancer efficacy and reduced normal tissue toxicities. Advances in this field are described which should lead to clinical studies of TEM8 targeted cancer therapeutics.

Federal Indian policy in the United States historically reflects both the hard-headed pragmatism of the nation and its quixotic romanticism. Researchers can identify roughly drawn policy epochs and policy motivations, but there were no clean slates as policy shifted. The legal history of a tribe reflects the accumulated—and often contradictory—impact of changing federal policy. Complexity was added to the government's approach by the application of single-minded policies to the exceedingly diverse native groups within the nation's borders. An understanding of evolving federal policy offers useful insights and a basis for creative legal theories.

American Indian tribes own substantial quantities of water, but often encounter obstacles to winning legal and public recognition of their water rights. Antiquated nineteenth century water regimes completely cut reservations out of water allocations throughout the arid western states, leaving many Indian lands unproductive, even as public funds built massive federal irrigation projects to provide low-cost water for other farmers. Since the 1960s, protracted and acrimonious litigation has forced some changes in the status quo. Today, weary participants in the water wars are increasingly accepting the reality of tribal water rights and negotiating settlements of water claims. This paper presents case studies illustrating tribal efforts to secure water rights. It briefly explains United States water law and identifies the legal basis of the Indian reserved water right. The paper concludes with research guidance and an annotated bibliography of selected printed and electronic sources.

Large commercial crops of morels are harvested annually from montane coniferous forests of the northwestern United States. Although some morels fruit annually in nondisturbed forests, others fruit copiously in areas experiencing fire, insect infestations, tree mortality, and soil disturbance. Many forest managers currently use thinning and prescribed fire to re-create forest conditions that existed before the advent of wide-scale fire suppression, thus opportunities exist to promote morel crops while achieving fire control and timber production goals. However, our limited understanding of morel productivity, diversity, and ecology hinders such synergistic management. We used morphological, genetic, and ecological data to identify and characterize five putative species found at our study sites. Three of these putative species fruited only on burned soils the first spring season following a wildfire. The other two putative species fruited in nonburned forests, in islands of nonburned soils in burned forests, or the second year following fire on burned soils. Unbiased landscape-level estimates of genus-level morel productivity (not partitioned by putative species) ranged from 80 to 4350 morels per hectare and from 0.550 to 9.080 kg per ha. Productivity followed the general trend of wildfire-burned forests>insect-damaged forests>healthy forests. We discuss the implications of our results for forest management.

This paper identifies and describes major themes in contemporary Alaska Native law. A selected and annotated bibliography is included to facilitate additional research.

Social behavior of the prairie vole, Microtus ochrogaster, including monogamy, mate guarding, philopatry, communal nesting, and territoriality, evolved as an adaptation to habitats with low food prevalent in the original range of the species. These behaviors are associated with low population densities and low amplitudes of fluctuation characteristic of low food habitats. In particular, reproductive activation of philopatric females by unfamiliar males is prevented owing to mate guarding and territorial defense. The basic social organization remains the same when populations occupy habitats with high food. However, in high food habitats mate guarding and territorial defense become less effective, resulting in reproductive activation of most philopatric females within communal groups. This contributes to the high population densities and amplitudes of fluctuation recorded from high food habitats.