Reliability and tolerance comparison in water supply networks

The final publication is available at Springer via http://dx.doi.org/10.1007/s11269-010-9753-2Urban water supply is a high priority service and so looped networks are extensively used in order to considerably reduce the number of consumers affected by a failure. Looped networks may be redundant in connectivity and capacity. The concept of reliability has been introduced in an attempt to quantitatively measure the possibility of maintaining an adequate service for a given period. Numerous researchers have considered reliability as a measure of redundancy. This concept is usually implicit, but some researchers have even stated it explicitly. This paper shows why reliability cannot be considered a measure of redundancy given that branched networks can achieve high values of reliability and this would deny the fact that a looped network is more reliable than a branched network with a similar layout and size. To this end the paper discusses two quantitative indices for measuring expected network behavior: reliability and tolerance. These indices are calculated and a comparison is made between looped, branched, and mixed networks. © 2011 Springer Science+Business Media B.V.The authors wish to acknowledge the support received from project IDAWAS, DPI2009-11591, of the Directorate-General of Research at the Spanish Ministry of Education, the grant PAID-02-09 for a stay at the Universidad Politecnica de Valencia by the first author, and a grant MAEC-AECI 0000202066 awarded to the second author by the Ministerio de Asuntos Exteriores y Cooperacion of Spain. The use of English in this paper was revised by John Rawlins; and the revision was funded by the Universidad Politecnica de Valencia, Spain.Martínez-Rodríguez, JB.; Montalvo Arango, I.; Izquierdo Sebastián, J.; Pérez García, R. (2011). Reliability and tolerance comparison in water supply networks. 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Antisocial behaviour and teacher–student relationship quality: The role of emotion‐related abilities and callous–unemotional traits

Background: Childhood antisocial behaviour has been associated with poorer teacher-student relationship (TSR) quality. It is also well-established that youth with antisocial behaviour have a range of emotion-related deficits, yet the impact of these students’ emotion-related abilities on the TSR is not understood. Furthermore, the addition of the Limited Prosocial Emotions specifier in the Diagnostic and Statistical Manual of Mental Disorders (DSM-5) indicates that understanding the role of callous-unemotional (CU) traits for youth with antisocial behaviour problems is of particular importance. Aims: The aim of this study was to investigate the association between antisocial behaviour difficulties and the TSR by examining the influence of emotion-related abilities and CU traits. Sample: Twelve teachers from 10 primary schools provided anonymised information on 108 children aged 6-11 years. Results: Antisocial behaviour was associated with higher teacher-student conflict (but not closeness) as well as higher emotion lability/negativity and lower emotion understanding/empathy. Emotion lability/negativity was associated with higher teacher-student conflict (but not closeness), and emotion understanding/empathy was associated with lower teacher-student conflict and higher closeness. CU traits was associated with higher teacher-student conflict and lower teacher-student closeness (controlling for antisocial behaviour more broadly). We found no evidence of a moderating effect of CU traits or emotion-related abilities on the association between antisocial behaviour and TSR quality. Conclusions: Interventions for behaviour difficulties should consider teacher-student relationships in the classroom. Strategies which aim to improve teacher-student closeness as well as reduce teacher-student conflict may be of particular value to students with high CU traits

Paraoxonase-1 is related to inflammation, fibrosis and PPAR delta in experimental liver disease

<p>Abstract</p> <p>Background</p> <p>Paraoxonase-1 (PON1) is an antioxidant enzyme synthesized by the liver. It protects against liver impairment and attenuates the production of the pro-inflammatory monocyte chemoattractant protein-1 (MCP-1). We investigated the relationships between hepatic PON1 and MCP-1 expression in rats with liver disease and explored the possible molecular mechanisms involved.</p> <p>Methods</p> <p>CCl₄was administered for up to 12 weeks to induce liver damage. Serum and hepatic levels of PON1 and MCP-1, their gene and protein expression, nuclear transcription factors, and histological and biochemical markers of liver impairment were measured.</p> <p>Results</p> <p>High levels of PON1 and MCP-1 expression were observed at 12^thweek in the hepatocytes surrounding the fibrous septa and inflammatory areas. CCl₄-administered rats had an increased hepatic PON1 concentration that was related to decreased gene transcription and inhibited protein degradation. Decreased PON1 gene transcription was associated with PPARδ expression. These changes were accompanied by increased hepatic MCP-1 concentration and gene expression. There were significant direct relationships between hepatic PON1 and MCP-1 concentrations (P = 0.005) and between PON1 and the amount of activated stellate cells (P = 0.001).</p> <p>Conclusion</p> <p>Our results from this experimental model suggest a hepato-protective role for PON1 against inflammation, fibrosis and liver disease mediated by MCP-1.</p

Angiotensin Converting Enzyme (ACE) and ACE2 Bind Integrins and ACE2 Regulates Integrin Signalling

The angiotensin converting enzymes (ACEs) are the key catalytic components of the renin-angiotensin system, mediating precise regulation of blood pressure by counterbalancing the effects of each other. Inhibition of ACE has been shown to improve pathology in cardiovascular disease, whilst ACE2 is cardioprotective in the failing heart. However, the mechanisms by which ACE2 mediates its cardioprotective functions have yet to be fully elucidated. Here we demonstrate that both ACE and ACE2 bind integrin subunits, in an RGD-independent manner, and that they can act as cell adhesion substrates. We show that cellular expression of ACE2 enhanced cell adhesion. Furthermore, we present evidence that soluble ACE2 (sACE2) is capable of suppressing integrin signalling mediated by FAK. In addition, sACE2 increases the expression of Akt, thereby lowering the proportion of the signalling molecule phosphorylated Akt. These results suggest that ACE2 plays a role in cell-cell interactions, possibly acting to fine-tune integrin signalling. Hence the expression and cleavage of ACE2 at the plasma membrane may influence cell-extracellular matrix interactions and the signalling that mediates cell survival and proliferation. As such, ectodomain shedding of ACE2 may play a role in the process of pathological cardiac remodelling

Evolution of pathotypes of Puccinia helianthi on sunflower in Australia

Sunflower rust caused by Puccinia helianthi is a major problem in sunflower production in Australia. The disease can be effectively controlled through the use of resistant hybrids but the commercial life of these is often short, due to the evolution of new pathotypes of the fungus. Since 1978, 23 pathotypes have been recognised, mostly from commercial crops. Possible pathways for the evolution of these pathotypes are proposed. Almost all pathotypes identified since 1986 trace to a common progenitor, Aus4. Avirulence/virulence patterns of many pathotypes suggest that sexual recombination may be acting to generate new pathotypes, but the sexual stages of the fungus are rarely seen in the field. It is assumed that bursts of evolution occur in seasons that favour completion of the sexual cycle, and that mutation contributes steadily to the development of new virulence genes in the population of P. helianthi

Aggressiveness among isolates of Sclerotinia sclerotiorum from sunflower

Isolates of Sclerotinia sclerotiorum differ significantly in aggressiveness on sunflower. In total, 120 isolates were collected from head and basal stem rots of sunflower in two locations in south-east Queensland, Australia. The inoculation of sunflower stems with mycelial plugs and the measurement of lesion development were used to compare aggressiveness between isolates. Rank ordering of isolates indicated differences, with a few isolates displaying high and low aggressive abilities. Differences in aggressiveness were more indicative of a continuous variation rather than discrete groups. Isolate aggressiveness did not correspond to the location of collection nor to the mode of pathogen reproduction or infection from which they were derived. Statistically significant differences between the isolates differed according to the statistical test employed, as different multiple comparison procedures had a greater influence in interpretation of aggressiveness than the isolates themselves. Results indicate individual isolates do not maintain discrete aggressive abilities across the multiple comparison procedures, with the exception of weakly aggressive isolates

Carpogenic germination of Sclerotinia minor and potential distribution in Australia

This study confirms that Australian isolates of Sclerotinia minor can produce fertile apothecia and further demonstrates that ascospores collected from these apothecia are pathogenic to sunflower (Helianthus annuus). Sunflower is a known host of the related fungus Sclerotinia sclerotiorum and is grown in some regions where S. minor is known to occur. Head rot symptoms were produced following inoculation with S. minor ascospores. Predictive modeling using CLIMEX software suggested that conditions suitable for carpogenic germination of S. minor probably occur in Australia particularly in southern regions. Carpogenic germination is probably a rare event in northern regions and, if it does occur, probably does not coincide with anthesis in sunflower crops, therefore allowing disease escape