Occurrence of LINE, gypsy-like, and copia-like retrotransposons in the clonally propagated sweet potato (Ipomoea batatas L.)

Retrotransposons are a class of transposable elements that represent a major fraction of the repetitive DNA of most eukaryotes. Their abundance stems from their expansive replication strategies. We screened and isolated sequence fragments of long terminal repeat (LTR), gypsy-like reverse transcriptase (rt) and gypsy-like envelope (env) domains, and two partial sequences of non-LTR retrotransposons, long interspersed element (LINE), in the clonally propagated allohexaploid sweet potato (Ipomoea batatas (L.) Lam.) genome. Using dot-blot hybridization, these elements were found to be present in the ~1597 Mb haploid sweet potato genome with copy numbers ranging from ~50 to ~4100 as observed in the partial LTR (IbLtr-1) and LINE (IbLi-1) sequences, respectively. The continuous clonal propagation of sweet potato may have contributed to such a multitude of copies of some of these genomic elements. Interestingly, the isolated gypsy-like env and gypsy-like rt sequence fragments, IbGy-1 (~2100 copies) and IbGy-2 (~540 copies), respectively, were found to be homologous to the Bagy-2 cDNA sequences of barley (Hordeum vulgare L.). Although the isolated partial sequences were found to be homologous to other transcriptionally active elements, future studies are required to determine whether they represent elements that are transcriptionally active under normal and (or) stressful conditions

Twin Peaks - The Legal and Regulatory Anatomy of Australia's System of Financial Regulation

Australia adopts a functionally-based model – the ‘twin peaks’ model – under which the functions for financial regulation are consolidated into two regulators: the Australian Securities and Investments Commission (ASIC), which is responsible for the regulation of companies, market conduct and consumer protection; and the Australian Prudential Regulation Authority (APRA), which is responsible for prudential regulation. This paper examines the anatomy of the Australian twin peaks model from a legal and regulatory perspective. It also reflects on the work of the Financial System Inquiry (FSI) of 2014, which reviewed Australia’s financial system and examined issues that are relevant to the operation of the twin peaks model

Heterosis in locally adapted sorghum genotypes and potential of hybrids for increased productivity in contrasting environments in Ethiopia

Increased productivity in sorghum has been achieved in the developed world using hybrids. Despite their yield advantage, introduced hybrids have not been adopted in Ethiopia due to the lack of adaptive traits, their short plant stature and small grain size. This study was conducted to investigate hybrid performance and the magnitude of heterosis of locally adapted genotypes in addition to introduced hybrids in three contrasting environments in Ethiopia. In total, 139 hybrids, derived from introduced seed parents crossed with locally adapted genotypes and introduced R lines, were evaluated. Overall, the hybrids matured earlier than the adapted parents, but had higher grain yield, plant height, grain number and grain weight in all environments. The lowland adapted hybrids displayed a mean better parent heterosis (BPH) of 19%, equating to 1160 kg ha− 1 and a 29% mean increase in grain yield, in addition to increased plant height and grain weight, in comparison to the hybrids derived from the introduced R lines. The mean BPH for grain yield for the highland adapted hybrids was 16% in the highland and 52% in the intermediate environment equating to 698 kg ha− 1 and 2031 kg ha− 1, respectively, in addition to increased grain weight. The magnitude of heterosis observed for each hybrid group was related to the genetic distance between the parental lines. The majority of hybrids also showed superiority over the standard check varieties. In general, hybrids from locally adapted genotypes were superior in grain yield, plant height and grain weight compared to the high parents and introduced hybrids indicating the potential for hybrids to increase productivity while addressing farmers' required traits

An analysis of penalties under ASIC administered legislation: scoping the issues

This working paper is the first published output of an eighteen month (December 2014 – June 2016) research project conducted by staff at the Melbourne Law School that examines enforcement and penalties regimes under legislation administered by the Australian Securities and Investments Commission (ASIC). During 2015 and early 2016 the project will conduct a review of selected penalties over a ten year period from 2005 to 2014. This paper is an introductory publication that scopes the issues that will be examined in the course of the project. The paper begins with a brief overview of the project and identifies topics that will be considered as the project progresses. Part II discusses key findings in ASIC’s Report 387: Penalties for Corporate Wrongdoing which compares the penalties available to ASIC in relation to comparable regulators in other jurisdictions. Part III examines current debates about corporate wrongdoing and the adequacy of penalties, including the impact of recent parliamentary inquiries. Part IV explains ASIC’s regulatory and enforcement functions and briefly discusses the policy rationales that underlie such functions. Part V presents a preliminary set of data on ASIC’s enforcement activity sourced from its six monthly Enforcement Reports. Part VI makes initial observations in relation to comparable financial market regulatory agencies in other jurisdictions by reference to various criteria, including funding models. Part VII concludes the working paper

Expression Pattern of the Alpha-Kafirin Promoter Coupled with a Signal Peptide from Sorghum bicolor L. Moench

Regulatory sequences with endosperm specificity are essential for foreign gene expression in the desired tissue for both grain quality improvement and molecular pharming. In this study, promoters of seed storage α-kafirin genes coupled with signal sequence (ss) were isolated from Sorghum bicolor L. Moench genomic DNA by PCR. The α-kafirin promoter (α-kaf) contains endosperm specificity-determining motifs, prolamin-box, the O2-box 1, CATC, and TATA boxes required for α-kafirin gene expression in sorghum seeds. The constructs pMB-Ubi-gfp and pMB-kaf-gfp were microprojectile bombarded into various sorghum and sweet corn explants. GFP expression was detected on all explants using the Ubi promoter but only in seeds for the α-kaf promoter. This shows that the α-kaf promoter isolated was functional and demonstrated seed-specific GFP expression. The constructs pMB-Ubi-ss-gfp and pMB-kaf-ss-gfp were also bombarded into the same explants. Detection of GFP expression showed that the signal peptide (SP)::GFP fusion can assemble and fold properly, preserving the fluorescent properties of GFP

Growth and survival of Cherax destructor and Bidyanus bidyanus stocked in a communal aquarium system

Polycultural aquaculture typically utilises a mix of low trophic level species to increase yield above that which can be obtained from a single species. Low trophic level species are not widely accepted for consumption within Australia, so this study focussed on two species that have market acceptance, the yabby (Cherax destructor) and the silver perch (Bidyanus bidyanus). Laboratory scale trials examined the effect of each species on the growth and survival of the other species as well as the role of shelter for crayfish in this system over a 13.5 week period. Neither species negatively impacted the growth of the other, however, survival was negatively impacted. Shelter enhanced crayfish survival, although fish survival was impacted in those treatments. A higher total biomass was harvested from polyculture treatments than monoculture treatments. The positive results warrant further investigation at the scale of mesocosm, prior to large-scale pond trials

Holocene drainage systems of the English Fenland : roddons and their environmental significance

The roddons of the English Fenlands are fossilised silt and sand-filled tidal creek systems of mid- to late-Holocene age, incised into contemporaneous clay deposits. However, anthropogenic change (drainage and agriculture) has caused the former channels to become positive topographical features. Three stratigraphically discrete generations of roddon have been discriminated. They all show well-developed dendritic meander patterns, but there is little or no evidence of sand/silt infill during meandering; thus, unlike modern tidal creeks and rivers they typically lack laterally stacked point bar deposits, suggesting rapid infill. Major “trunk” roddons are rich in fine sands and there is little change in grain size from roddon mouth to the upper reaches, suggesting highly effective sand transport mechanisms and uniform conditions of deposition. Tributaries are silt-rich, while minor tributaries also have a significant clay component. During infill, active drainage networks appear to have been choked by sediment, converting mudflat/salt-marsh environments into widespread peat-forming freshwater reed swamps

The role of feed supplements in improving intake and utilisation of low quality roughage in ruminants

The studies in this thesis were undertaken to investigate ways to improve the value of roughages and byproducts as feeds for ruminants through supplementation. Low quality basal roughages are high in fibre, low in N and other minerals; as a result their comminution rate in the rumen (and clearance rate) is generally low, leading to low intake. Moreover, their digestion in the gut often results in absorption of digestion products that are imbalanced in protein to energy (PIE), and also in glucogenic to acetogenic substrates. The imbalance in nutrients leads to inefficiency in the utilisation of the absorbed nutrients, often manifesting as high heat increment and generally low voluntary intake (MacRae and Lobley 1982; MacRae et al. 1987). This problem is further compounded by the high ambient temperature in the tropics where most of the ruminant livestock subsisting on crop residues are raised, which makes dissipation of heat very difficult (Preston and Leng 1987; Leng 1990). Animals in the tropical environments therefore respond to low digestibility feeds by reducing feed intake which leads to lower animal productivity (Preston and Leng 1987). This study investigated how strategic supplementation with rumen degradable nutrients and by-pass nutrients in animals fed low quality roughage basal diets may be used to stimulate an efficient rumen fermentation (and intestinal digestion). It was hypothesized that this is likely to result in the absorption of balanced nutrients (PIE and glucogeniclacetogenic ratio) from the gut, and therefore enhance efficiency in nutrient metabolism in the body tissues, resulting in improved animal productivity (Leng 1990). The broad objective of the present study was to investigate the role of dietary N, protein and energy supplementation and ammoniation with urea in stimulating higher rumen fermentation, with a view of providing the small intestines with a better balance of protein and energy substrates (P: E), as well as of glucogenic to acetogenic substrates for digestion and absorption. It was hypothesized that when the body tissues are provided with balanced nutrients, this would lead to more efficient utilisation of those nutrients, lower heat production, and therefore higher animal productivity

Impact of gut kinetics on methane production within the sheep

Methane emissions from ruminant livestock is a major source of greenhouse gases, accounting for approximately two-thirds of anthropogenic methane sources. Methane yield from ruminants (MY; g/kg DM intake) is known to be positively correlated with the mean retention time (MRT) of rumen contents, and MRT in the rumen is largely controlled by the contractile forces of the reticulo-rumen and the relaxing of the reticulo-omasal orifice. The discovery of immuno-reactive endocrine and neural cells distributed throughout the epithelia and glands of the digestive tract suggest that the endocrine system may play a key role in regulating digesta MRT and MY in ruminants. The thyroid hormone triiodothyronine (T₃), known to influence digesta kinetics, was used to initiate our studies to modify digesta MRT and determine the impact that digesta MRT has on the production of enteric methane and MY. To investigate the influence digesta kinetics had on ruminant MY, it was necessary to develop a kinetic model capable of accurately estimating the rate of flow of digesta through the digestive tract. An extensive review of existing published mathematical models for ruminant digesta kinetics was conducted and a model developed by Aharoni et al. (1999) for the estimation of cattle digesta kinetics was selected and modified to produce a new multicompartmental double-marker digestive tract model for use in sheep