Still in Search of the Good Life

At the 2014 G20 held in Brisbane, Australia took the position that climate change is not an economic issue. Most others thought it was - especially the Turkish Prime Minister who is hosting the 2015 G20. It is certainly an economic issue. But, it is not just an economic issue - either in the source or the solution.

Oscillatory flow in an elastic tube of variable cross-section

An oscillatory flow of a viscous incompressible fluid in an elastic tube of variable cross section has been investigated at low Reynolds number. The equations governing, the flow are derived under the assumption that the variation of the cross-section is slow in the axial direction for a tethered tube. The problem is then reduced to that of solving for the excess pressure from a second order ordinary differential equation with complex valued Bessel functions as the coefficients. This equation has been solved numerically for geometries of physiological interest and a comparison is made with some of the known theoretical and experimental results.

A novel species of mastrevirus (family Geminiviridae) isolated from Digitaria didactyla grass from Australia.

Mastreviruses (family Geminiviridae) that infect monocotyledonous plants occur throughout the temperate and tropical regions of Asia, Africa, Europe and Australia. Despite the identification of a very diverse array of mastrevirus species whose members infect African monocots, few such species have been discovered in other parts of the world. For example, the sequence of only a single monocot-infecting mastrevirus, Chloris striate mosaic virus (CSMV), has been reported so far from Australia, even though earlier biological and serological studies suggested that other distinct mastreviruses were present. Here, we have obtained the complete nucleotide sequence of a virus from the grass Digitaria didactyla originating from Australia. Analysis of the sequence shows the virus to be a typical mastrevirus, with four open reading frames, two in each orientation, separated by two non-coding intergenic regions. Although it showed the highest levels of sequence identity to CSMV (68.7%), their sequences are sufficiently diverse for the virus to be considered a member of a new species in the genus Mastrevirus, based on the present species demarcation criteria. We propose that the name first used during the 1980s be used for this species, Digitaria didactyla striate mosaic virus (DDSMV).

A proposal to change existing virus species names to non-Latinized binomials.

A proposal has been posted on the ICTV website (2011.001aG.N.v1.binomial_sp_names) to replace virus species names by non-Latinized binomial names consisting of the current italicized species name with the terminal word "virus" replaced by the italicized and non-capitalized genus name to which the species belongs. If implemented, the current italicized species name Measles virus, for instance, would become Measles morbillivirus while the current virus name measles virus and its abbreviation MeV would remain unchanged. The rationale for the proposed change is presented.

Two novel mastreviruses from chickpea (Cicer arietinum) in Australia

Two novel mastreviruses (genus Mastrevirus; family Geminiviridae), with proposed names chickpea chlorosis virus (CpCV) and chickpea redleaf virus, are described from chickpea (Cicer arietinum) from eastern Australia. The viruses have genomes of 2,582 and 2,605 nucleotides, respectively, and share similar features and organisation with typical dicot-infecting mastreviruses. Two distinct strains of CpCV were suggested by phylogenetic analysis. Additionally, a partial mastrevirus Rep sequence from turnip weed (Rapistrum rugosum) indicated the presence of a distinct strain of Tobacco yellow dwarf virus (TYDV). In phylogenetic analyses, isolates of Bean yellow dwarf virus, Chickpea chlorotic dwarf Pakistan virus and Chickpea chlorotic dwarf Sudan virus from southern and northern Africa and south-central and western Asia clustered separately from these three viruses from Australia. An Australian, eastern Asian, or south-eastern Asian origin for the novel mastreviruses and TYDV is discussed.

Behavior Of High-Voltage Machine Insulation System In The Presence Of Thermal And Electrical Stresses

This paper presents the results on a resin-rich machine insulation system subjected to varying stresses such as electrical (2.6 to 13.3 MV/m) and thermal (40 to 155° C) acting together. Accelerated electro-thermal aging experiments subsequently have been performed to understand the insulation degradation The interpretations are based on several measured properties like capacitance, loss tangent, ac resistance, leakage current, and partial discharge quantities. The results indicate that the changes in properties are not significant below a certain temperature for any applied stress, Beyond this temperature large variations are observed even for low electrical stresses. Electrothermal aging studies reveal that the acceleration of the insulation degradation and the ultimate time to failure depends on the relative values of temperature and voltage stresses. At lower temperatures, below critical, material characteristics of the system predominate whereas beyond this temperature, other phenomena come into play causing insulation deterioration. During aging under combined stresses, it appears that the prevailing temperature of the system has a significant role in the insulation degradation and ultimate failure.

Immunodeficiencies, pathogens and sex in upper respiratory diseases

In the first part of this thesis the association of different forms of sinonasal diseases and plasma concentrations of C3, C4, immunoglobulins, immunoglobulin G subclasses, C4A and C4B gene numbers were studied in 287 adult patients and 150 sex-matched adult controls. Patients were well characterized and stratified into groups using strict clinical criteria and females and males were also studied as separate groups. Severe primary antibody antibody deficiencies were rare in patients coming to sinonasal operations. Female patients had more recurrent sinusitis and other mucosal infections and males had more nasal polyposis. Upregulation of complement activity was seen in acute rhinosinusitis patients (high levels of plasma C3, C4, and complement classical pathway activity CH50) and male patients coming to sinonasal operations (high levels of plasma C3 and C4). In females, total and partial C4B deficiencies and lower levels of IgG1 and IgG3 were associated with rhinosinusitis leading to sinonasal operations. C4A deficiencies were found to predispose to severe chronic rhinosinusitis in females and males. In female patients with chronic or recurrent rhinosinusitis with nasal polyposis C4B deficiencies seem to predispose to the disease, but in males with a similar disease C4B deficiencies seem to be protective. This suggests a different pathophysiology between sexes in this form of sinonasal disease. In the second part of this thesis work 213 children coming to elective tonsillectomy were studied and compared with 155 randomly selected school children. An association with recurrent upper respiratory tract infections and hypersensitivity disorders was seen especially in children under 7 years of age. However, this association was not seen in levels of specific IgE to respiratory allergens in the same age group. Both symptomatic respiratory allergy and specific IgE to respiratory allergens became more common in boys than girls over 7 years of age. We were able to show that although both rhinoviruses and bacterial pathogens were found in the tonsils, no association between their presence and clinical forms of tonsillar disease was seen. The ability of GAS to bind complement regulators FH and C4BP did not differ between strains causing tonsillar diseases or septicemia, suggesting that other virulence mechanisms of the bacteria are more important.

Polypharmacy among inpatients aged 70 years or older in Australia

Objectives To investigate medication changes for older patients admitted to hospital and to explore associations between patient characteristics and polypharmacy. Design Prospective cohort study. Participants and setting Patients aged 70 years or older admitted to general medical units of 11 acute care hospitals in two Australian states between July 2005 and May 2010. All patients were assessed using the interRAI assessment system for acute care. Main outcome measures Measures of physical, cognitive and psychosocial functioning; and number of regular prescribed medications categorised into three groups: non-polypharmacy (0–4 drugs), polypharmacy (5–9 drugs) and hyperpolypharmacy (≥ 10 drugs). Results Of 1220 patients who were recruited for the study, medication records at admission were available for 1216. Mean age was 81.3 years (SD, 6.8 years), and 659 patients (54.2%) were women. For the 1187 patients with complete medication records on admission and discharge, there was a small but statistically significant increase in mean number of regular medications per day between admission and discharge (7.1 v 7.6), while the prevalence of medications such as statins (459 [38.7%] v 457 [38.5%] patients), opioid analgesics (155 [13.1%] v 166 [14.0%] patients), antipsychotics (59 [5.0%] v 65 [5.5%] patients) and benzodiazepines (122 [10.3%] v 135 [11.4%] patients) did not change significantly. Being in a higher polypharmacy category was significantly associated with increase in comorbidities (odds ratio [OR], 1.27; 95% CI, 1.20–1.34), presence of pain (OR, 1.31; 1.05–1.64), dyspnoea (OR, 1.64; 1.30–2.07) and dependence in terms of instrumental activities of daily living (OR, 1.70; 1.20–2.41). Hyperpolypharmacy was observed in 290/1216 patients (23.8%) at admission and 336/1187 patients (28.3%) on discharge, and the proportion of preventive medication in the hyperpolypharmacy category at both points in time remained high (1209/3371 [35.9%] at admission v 1508/4117 [36.6%] at discharge). Conclusions Polypharmacy is common among older people admitted to general medical units of Australian hospitals, with no clinically meaningful change to the number or classification (symptom control, prevention or both) of drugs made by treating physicians.

Intermediary Analysis in Propellant Decomposition

Formation of benzaldehyde and benzoic acid have been observed during the slow decomposition of polystyrene/ammonium perchlorale propellant. This has been attributed to the formation of polystyrene peroxide intermediate which on decomposition gives the above producis. The chemical scheme for the formation of polystyrene peroxide has been presented.

Binding of polyphenols to plant cell wall analogues - Part 1: Anthocyanins

Anthocyanins are located within the vacuole of plant cells, and are released following cell rupture during eating or processing at which time they first come into contact with the plant cell wall. The extent of anthocyanin-cell wall interaction was investigated by monitoring the rate of anthocyanin depletion in the presence of pure cellulose or cellulose-pectin composites as cell wall models. It was found that anthocyanins interact with both cellulose and pectin over a two-stage process with initially (mins-hours) 13 similar to 18% of anthocyanins binding to cellulose or cellulose/pectincomposites. With prolonged exposure (days-weeks), a gradual increase in anthocyanin binding occurs, possibly due to anthocyanins stacking on top of a base layer. Binding of acylated and non-acylated anthocyanins followed a similar pattern with slightly more (5-10%) binding of the acylated forms. Composites with the highest pectin content had the greatest anthocyanin binding suggesting the existence of both ionic interactions (with pectin) and hydrophobic interactions (with cellulose) of anthocyanin with plant cell walls.

Design and testing of stand-specific bucking instructions for use on modern cut-to-length harvesters

This study addresses three important issues in tree bucking optimization in the context of cut-to-length harvesting. (1) Would the fit between the log demand and log output distributions be better if the price and/or demand matrices controlling the bucking decisions on modern cut-to-length harvesters were adjusted to the unique conditions of each individual stand? (2) In what ways can we generate stand and product specific price and demand matrices? (3) What alternatives do we have to measure the fit between the log demand and log output distributions, and what would be an ideal goodness-of-fit measure? Three iterative search systems were developed for seeking stand-specific price and demand matrix sets: (1) A fuzzy logic control system for calibrating the price matrix of one log product for one stand at a time (the stand-level one-product approach); (2) a genetic algorithm system for adjusting the price matrices of one log product in parallel for several stands (the forest-level one-product approach); and (3) a genetic algorithm system for dividing the overall demand matrix of each of the several log products into stand-specific sub-demands simultaneously for several stands and products (the forest-level multi-product approach). The stem material used for testing the performance of the stand-specific price and demand matrices against that of the reference matrices was comprised of 9 155 Norway spruce (Picea abies (L.) Karst.) sawlog stems gathered by harvesters from 15 mature spruce-dominated stands in southern Finland. The reference price and demand matrices were either direct copies or slightly modified versions of those used by two Finnish sawmilling companies. Two types of stand-specific bucking matrices were compiled for each log product. One was from the harvester-collected stem profiles and the other was from the pre-harvest inventory data. Four goodness-of-fit measures were analyzed for their appropriateness in determining the similarity between the log demand and log output distributions: (1) the apportionment degree (index), (2) the chi-square statistic, (3) Laspeyres quantity index, and (4) the price-weighted apportionment degree. The study confirmed that any improvement in the fit between the log demand and log output distributions can only be realized at the expense of log volumes produced. Stand-level pre-control of price matrices was found to be advantageous, provided the control is done with perfect stem data. Forest-level pre-control of price matrices resulted in no improvement in the cumulative apportionment degree. Cutting stands under the control of stand-specific demand matrices yielded a better total fit between the demand and output matrices at the forest level than was obtained by cutting each stand with non-stand-specific reference matrices. The theoretical and experimental analyses suggest that none of the three alternative goodness-of-fit measures clearly outperforms the traditional apportionment degree measure. Keywords: harvesting, tree bucking optimization, simulation, fuzzy control, genetic algorithms, goodness-of-fit

Novel role of the nitrite transporter NirC in Salmonella pathogenesis: SPI2-dependent suppression of inducible nitric oxide synthase in activated macrophages

Activation of macrophages by interferon gamma (IFN- ) and the subsequent production of nitric oxide (NO) are critical for the host defence against Salmonella enterica serovar Typhimurium infection. We report here the inhibition of IFN- -induced NO production in RAW264.7 macrophages infected with wild-type Salmonella. This phenomenon was shown to be dependent on the nirC gene, which encodes a potential nitrite transporter. We observed a higher NO output from IFN- -treated macrophages infected with a nirC mutant of Salmonella. The nirC mutant also showed significantly decreased intracellular proliferation in a NO-dependent manner in activated RAW264.7 macrophages and in liver, spleen and secondary lymph nodes of mice, which was restored by complementing the gene in trans. Under acidified nitrite stress, a twofold more pronounced NO-mediated repression of SPI2 was observed in the nirC knockout strain compared to the wild-type. This enhanced SPI2 repression in the nirC knockout led to a higher level of STAT-1 phosphorylation and inducible nitric oxide synthase (iNOS) expression than seen with the wild-type strain. In iNOS knockout mice, the organ load of the nirC knockout strain was similar to that of the wild-type strain, indicating that the mutant is exclusively sensitive to the host nitrosative stress. Taken together, these results reveal that intracellular Salmonella evade killing in activated macrophages by downregulating IFN- -induced NO production, and they highlight the critical role of nirC as a virulence gene.

Multiplication of hybrid aspen (Populus tremula L. x P. tremuloides Michx.) from cuttings

The primary aim of the present study was to find an efficient and simple method of vegetative propagation for producing large numbers of hybrid aspen (Populus tremuloides L. x P. tremula Michx.) plants for forest plantations. The key objectives were to investigate the main physiological factors that affect the ability of cuttings to regenerate and to determine whether these factors could be manipulated by different growth conditions. In addition, clonal variation in traits related to propagation success was examined. According to our results, with the stem cutting method, depending on the clone, it is possible to obtain only 1−8 plants from one stock plant per year. With the root cutting method the corresponding values for two-year-old stock plants are 81−207 plants. The difference in number of cuttings between one- and two-year-old stock plants is so pronounced that it is economically feasible to grow stock plants for two years. There is no reason to use much older stock plants as a source of cuttings, as it has been observed that rooting ability diminishes as root diameter increases. Clonal variation is the most important individual factor in propagation of hybrid aspen. The fact that the efficiently sprouted clones also rooted best facilitates the selection of clones for large-scale propagation. In practice, root cuttings taken from all parts of the root system of hybrid aspen were capable of producing new shoots and roots. However, for efficient rooting it is important to use roots smaller than one centimeter in diameter. Both rooting and sprouting, as well as sprouting rate, were increased by high soil temperature; in our studies the highest temperature tested (30ºC) was the best. Light accelerated the sprouting of root cuttings, but they rooted best in dark conditions. Rooting is essential because without roots the sprouted cutting cannot survive long. For aspen the criteria for clone selection are primarily fiber qualities and growth rate, but ability to regenerate efficiently is also essential. For large-scale propagation it is very important to find clones from which many cuttings per stock plant can be obtained. In light of production costs, however, it is even more important that the regeneration ability of the produced cuttings be high.

Are high-impact species predictable? An analysis of naturalised grasses in northern Australia

Predicting which species are likely to cause serious impacts in the future is crucial for targeting management efforts, but the characteristics of such species remain largely unconfirmed. We use data and expert opinion on tropical and subtropical grasses naturalised in Australia since European settlement to identify naturalised and high-impact species and subsequently to test whether high-impact species are predictable. High-impact species for the three main affected sectors (environment, pastoral and agriculture) were determined by assessing evidence against pre-defined criteria. Twenty-one of the 155 naturalised species (14%) were classified as high-impact, including four that affected more than one sector. High-impact species were more likely to have faster spread rates (regions invaded per decade) and to be semi-aquatic. Spread rate was best explained by whether species had been actively spread (as pasture), and time since naturalisation, but may not be explanatory as it was tightly correlated with range size and incidence rate. Giving more weight to minimising the chance of overlooking high-impact species, a priority for biosecurity, meant a wider range of predictors was required to identify high-impact species, and the predictive power of the models was reduced. By-sector analysis of predictors of high impact species was limited by their relative rarity, but showed sector differences, including to the universal predictors (spread rate and habitat) and life history. Furthermore, species causing high impact to agriculture have changed in the past 10 years with changes in farming practice, highlighting the importance of context in determining impact. A rationale for invasion ecology is to improve the prediction and response to future threats. Although our study identifies some universal predictors, it suggests improved prediction will require a far greater emphasis on impact rather than invasiveness, and will need to account for the individual circumstances of affected sectors and the relative rarity of high-impact species.