Phosphodiesterase PDE3, but not PDE4, reduces β1- and β2-adrenoceptor-mediated inotropic and lusitropic effects in failing ventricle from metoprolol-treated patients

Background and purpose Phosphodiesterases PDE3 and/or PDE4 control ventricular effects of catecholamines in several species but their relative effects in failing human ventricle are unknown. We investigated whether the PDE3-selective inhibitor cilostamide (0.3-1μM) or PDE4 inhibitor rolipram (1-10μM) modified the positive inotropic and lusitropic effects of catecholamines in human failing myocardium. Experimental approach Right and left ventricular trabeculae from freshly explanted hearts of 5 non-β-blocker-treated and 15 metoprolol-treated patients with terminal heart failure were paced to contract at 1Hz. The effects of (-)-noradrenaline, mediated through β1-adrenoceptors (β2-adrenoceptors blocked with ICI118551), and (-)-adrenaline, mediated through β2-adrenoceptors (β1-adrenoceptors blocked with CGP20712A), were assessed in the absence and presence of PDE inhibitors. Catecholamine potencies were estimated from –logEC50s. Key results Cilostamide did not significantly potentiate the inotropic effects of the catecholamines in non-β-blocker-treated patients. Cilostamide caused greater potentiation (P=0.037) of the positive inotropic effects of (-)-adrenaline (0.78±0.12 log units) than (-)-noradrenaline (0.47±0.12 log units) in metoprolol-treated patients. Lusitropic effects of the catecholamines were also potentiated by cilostamide. Rolipram did not affect the inotropic and lusitropic potencies of (-)-noradrenaline or (-)-adrenaline on right and left ventricular trabeculae from metoprolol-treated patients. Conclusions and implications Metoprolol induces a control by PDE3 of ventricular effects mediated through both β1- and β2-adrenoceptors, thereby further reducing sympathetic cardiostimulation in patients with terminal heart failure. Concurrent therapy with a PDE3 blocker and metoprolol could conceivably facilitate cardiostimulation evoked by adrenaline through β2-adrenoceptors. PDE4 does not appear to reduce inotropic and lusitropic effects of catecholamines in failing human ventricle.

Poly(2,5-bis(2-octyldodecyl)-3,6-di(furan-2-yl)-2,5-dihydro-pyrrolo[3,4-c] pyrrole-1,4-dione-co-thieno[3,2-b]thiophene): A high performance polymer semiconductor for both organic thin film transistors and organic photovoltaics

A new diketopyrrolopyrrole (DPP)-containing donor-acceptor polymer, poly(2,5-bis(2-octyldodecyl)-3,6-di(furan-2-yl)-2,5-dihydro-pyrrolo[3,4-c] pyrrole-1,4-dione-co-thieno[3,2-b]thiophene) (PDBF-co-TT), is synthesized and studied as a semiconductor in organic thin film transistors (OTFTs) and organic photovoltaics (OPVs). High hole mobility of up to 0.53 cm 2 V -1 s -1 in bottom-gate, top-contact OTFT devices is achieved owing to the ordered polymer chain packing and favoured chain orientation, strong intermolecular interactions, as well as uniform film morphology of PDBF-co-TT. The optimum band gap of 1.39 eV and high hole mobility make this polymer a promising donor semiconductor for the solar cell application. When paired with a fullerene acceptor, PC 71BM, the resulting OPV devices show a high power conversion efficiency of up to 4.38% under simulated standard AM1.5 solar illumination.

3,6-Di(furan-2-yl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione and bithiophene copolymer with rather disordered chain orientation showing high mobility in organic thin film transistors

Pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione or diketopyrrolopyrrole (DPP) is a useful electron-withdrawing fused aromatic moiety for the preparation of donor-acceptor polymers as active semiconductors for organic electronics. This study uses a DPP-furan-containing building block, 3,6-di(furan-2-yl)pyrrolo[3,4- c]pyrrole-1,4(2H,5H)-dione (DBF), to couple with a 2,2′-bithiophene unit, forming a new donor-acceptor copolymer, PDBFBT. Compared to its structural analogue, 3,6-di(thiophen-2-yl)pyrrolo[3,4-c]pyrrole-1,4(2H,5H)-dione (DBT), DBF is found to cause blue shifts of the absorption spectra both in solution and in thin films and a slight reduction of the highest occupied molecular orbital (HOMO) energy level of the resulting PDBFBT. Despite the fact that its thin films are less crystalline and have a rather disordered chain orientation in the crystalline domains, PDBFBT shows very high hole mobility up to 1.54 cm 2 V-1 s-1 in bottom-gate, top-contact organic thin film transistors.

Solution processable poly(2,5-dialkyl-2,5-dihydro-3,6-di-2-thienyl- pyrrolo[3,4-c]pyrrole-1,4-dione) for ambipolar organic thin film transistors

Solution processable diketopyrrolopyrrole (DPP)-bithiophene polymers (PDBT) with long branched alkyl side chains on the DPP unit are synthesized. These polymers have favourable highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) energy levels for the injection and transport of both holes and electrons. Organic thin film transistors (OTFTs) using these polymers as semiconductors and gold as source/drain electrodes show typical ambipolar characteristics with very well balanced high hole and electron mobilities (μ h = 0.024 cm 2 V -1 s -1 and μ e = 0.056 cm 2 V -1 s -1). These simple and high-performing polymers are promising materials for ambipolar organic thin film transistors for low-cost CMOS-like logic circuits.

Exploitation of the menshutkin reaction for the controlled assembly of halogen bonded architectures incorporating 1,2-diiodotetrafluorobenzene and 1,3,5-Triiodotrifluorobenzene

1,4-Diazabicyclo[2.2.2]octane (DABCO) forms well-defined co-crystals with 1,2-diiodotetrafluorobenzene (1,2-DITFB), [(1,2-DITFB)2DABCO], and 1,3,5-triiodotrifluorobenzene, [(1,3,5-TITFB)2DABCO]. Both systems exhibited lower-than-expected supramolecular connectivity, which inspired a search for polymorphs in alternative crystallization solvents. In dichloromethane solution, the Menshutkin reaction was found to occur, generating chloride anions and quaternary ammonium cations through the reaction between the solvent and DABCO. The controlled in situ production of chloride ions facilitated the crystallization of new halogen bonded networks, DABCO–CH2Cl[(1,2-DITFB)Cl] (zigzag X-bonded chains) and (DABCO–CH2Cl)3[(1,3,5-TITFB)2Cl3]·CHCl3 (2D pseudo-trigonal X-bonded nets displaying Borremean entanglement), propagating with charge-assisted C–I···Cl– halogen bonds. The method was found to be versatile, and substitution of DABCO with triethylamine (TEA) gave (TEA-CH2Cl)3[(1,2-DITFB)Cl3]·4(H2O) (mixed halogen bond hydrogen bond network with 2D supramolecular connectivity) and TEA-CH2Cl[(1,3,5-TITFB)Cl] (tightly packed planar trigonal nets). The co-crystals were typically produced in high yield and purity with relatively predictable supramolecular topology, particularly with respect to the connectivity of the iodobenzene molecules. The potential to use this synthetic methodology for crystal engineering of halogen bonded architectures is demonstrated and discussed.

Demonstration of regulatory cross-talk between P fimbriae and type 1 fimbriae in uropathogenic Escherichia coli

The majority of Escherichia coli strains isolated from urinary tract infections have the potential to express multiple fimbriae. Two of the most common fimbrial adhesins are type 1 fimbriae and pyelonephritis-associated pili (Pap). Previous research has shown that induced, plasmid-based expression of a Pap regulator, papB, and its close homologues can prevent inversion of the fim switch controlling the expression of type 1 fimbriae. The aim of the present study was to determine if this cross-regulation occurs when PapB is expressed from its native promoter in the chromosome of E. coli K-12 and clinical isolates. The regulation was examined in three ways: (1) mutated alleles of the pap regulatory region, including papB and papI, that maintain the pap promoter in either the off or the on phase were exchanged into the chromosome of both E. coli K-12 and the clinical isolate E. coli CFT073, and the effect on type 1 fimbrial expression was measured; (2) type 1 fimbrial expression was determined using a novel fimS : : gfp+ reporter system in mutants of the clinical isolate E. coli 536 in which combinations of complete fimbrial clusters had been deleted; (3) type 1 fimbrial expression was determined in a range of clinical isolates and compared with both the number of P clusters and their expression. All three approaches demonstrated that P expression represses type 1 fimbrial expression. Using a number of novel genetic approaches, this work extends the initial finding that PapB inhibits FimB recombination to the impact of this regulation in clinical isolates.

Review of Latecomers

This is a review of a poetry book by Jaya Savige (Latecomers, University of Qld Press, 2005), which explores contemporary poetics.

Contemporary consumer law : the role and effectiveness of regulation in consumer protection

This issue of the Griffith Law Review focuses on consumer law, and the pervasive nature of this area of law. We are all consumers, but do not necessarily identify as such, nor are we a homogeneous group. The boundaries of

Gender differences in children's classroom behaviour and teacher-child relationships in early childhood: An Australian Study

Background: In the early school years, children need positive attitudes to school and experiences that promote academic and social competence. Positive relationships between children and teachers make a significant contribution to school achievement and social competence. Girls are more likely to display positive classroom behaviours and positive approaches to learning than boys. Gender differences have also been noted in teacher-child relationships. This study investigated the relationship between gender differences in classroom behaviour and gender differences in teacher-child relationships in the early years. Method: Data were drawn from The Longitudinal Study of Australian Children (LSAC). LSAC is a cross-sequential cohort study funded by the Australian Government. In these analyses, Wave 1 (2004) and Wave 2 (2006) data for 4464 children in the Kindergarten Cohort were used. Children, at Wave 2, were in the early years of formal school. They had a mean age of 6.8 years (SD= 0.24). Measures included a 6-item measure of Approaches to Learning (task persistence, independence) and teacher ratings on the SDQ. Teachers rated their relationships with children on the short form of the STRS. Results: Girls were found to have more positive relationships with their teachers and to display more positive classroom behaviours than boys. Teachers described their relationships with boys as less close than their relationships with girls and rated girls as displaying more positive approaches to learning and fewer problem behaviours than boys. Positive teacher – child relationships were significantly related to more positive classroom behaviours. The quality of the teacher-child relationship at time 1 (Wave 1) was the best predictor of the quality of the teacher-child relationship at time 2 (Wave 2). Conclusions: Findings highlight the importance of developing positive learning related classroom behaviours in understanding successful school transition and the key role played by early positive teacher-child relationships in promoting school adjustment.

How well are Australian children doing in the first year of school : a demographic analysis

Background: The transition to school is a sensitive period for children in relation to school success. In the early school years, children need to develop positive attitudes to school and have experiences that promote academic, behavioural and social competence. When children begin school there are higher expectations of responsibility and independence and in the year one class, there are more explicit academic goals for literacy and numeracy and more formal instruction. Most importantly, children’s early attitudes to learning and learning styles have an impact on later educational outcomes. Method: Data were drawn from The Longitudinal Study of Australian Children (LSAC). LSAC is a cross-sequential cohort study funded by the Australian Government. In these analyses, Wave 2 (2006) data for 2499 children in the Kindergarten Cohort were used. Children, at Wave 2, were in the first year of formal school. They had a mean age of 6.9 years (SD= 0.26). Measures included a 6-item measure of Approaches to Learning (task persistence, independence) and the Academic Rating Scales for language and literacy and mathematical thinking. Teachers rated their relationships with children on the short form of the STRS. Results: Girls were rated by their teachers as doing better than boys on Language and literacy, Approaches to learning; and they had a better relationship with their teacher. Children from an Aboriginal or Torres Strait Island (ATSI) background were rated as doing less well on Language and Literacy and Mathematical thinking and on their Approaches to learning. Children from high Socio Economic Position families are doing better on teacher rated Language and Literacy, Mathematical thinking, Approaches to learning and they had a better relationship with their teacher. Conclusions: Findings highlight the importance of key demographic variables in understanding children’s early school success.

How well are Australian children doing in the first year of school?

Background: The transition to school is a sensitive period for children in relation to school success. In the early school years, children need to develop positive attitudes to school and have experiences that promote academic, behavioural and social competence. When children begin school there are higher expectations of responsibility and independence and in the year one class, there are more explicit academic goals for literacy and numeracy and more formal instruction. Most importantly, children’s early attitudes to learning and learning styles have an impact on later educational outcomes. Method: Data were drawn from The Longitudinal Study of Australian Children (LSAC). LSAC is a cross-sequential cohort study funded by the Australian Government. In these analyses, Wave 2 (2006) data for 2499 children in the Kindergarten Cohort were used. Children, at Wave 2, were in the first year of formal school. They had a mean age of 6.9 years (SD= 0.26). Measures included a 6-item measure of Approaches to Learning (task persistence, independence) and the Academic Rating Scales for language and literacy and mathematical thinking. Teachers rated their relationships with children on the short form of the STRS. Results: Girls were rated by their teachers as doing better than boys on Language and literacy, Approaches to learning; and they had a better relationship with their teacher. Children from an Aboriginal or Torres Strait Island (ATSI) background were rated as doing less well on Language and Literacy and Mathematical thinking and on their Approaches to learning. Children from high Socio Economic Position families are doing better on teacher rated Language and Literacy, Mathematical thinking, Approaches to learning and they had a better relationship with their teacher. Conclusions: Findings highlight the importance of key demographic variables in understanding children’s early school success.

Same-sex intimate partner violence : exploring the parameters

Intimate partner violence (IPV) is not only a problem for heterosexual couples. Although research in the area is beset by methodological and definitional problems, studies generally demonstrate that IPV also affects those who identify as non-heterosexual; that is, those sexualities that are typically categorized as lesbian, gay, bisexual, transgender, or intersex (LGBTI). IPV appears to be at least as prevalent in LGBTI relationships as it is in heterosexual couples, and follows similar patterns (e.g. Australian Research Centre on Sex, Health and Society 2006; Donovan et al. 2006; Chan 2005; Craft and Serovich 2005; Burke et al. 2002; Jeffries and Ball 2008; Kelly and Warshafsky 1987; Letellier 1994; Turrell 2000; Ristock 2003; Vickers 1996). There is, however, little in the way of specific community or social services support available to either victims or perpetrators of violence in same-sex relationships (see Vickers 1996). In addition, there are important differences in the experience of IPV between LGBTI and non-LGBTI victims, and even among LGBTI individuals; for example, among transgender populations (Chan 2005), and those who are HIV sero-positive (Craft and Serovich 2005). These different experiences of IPV include the use of HIV and the threat of “outing” a partner as tools of control, as just two examples (Jeffries and Ball 2008; Salyer 1999; WA Government 2008b). Such differences impact on how LGBTI victims respond to the violence, including whether or not and how they seek help, what services they are able to avail themselves of, and how likely they are to remain with, or return to, their violent partners (Burke et al. 2002). This chapter explores the prevalent heteronormative discourses that surround IPV, both within the academic literature, and in general social and government discourses. It seeks to understand how same-sex IPV remains largely invisible, and suggests that these dominant discourses play a major role in maintaining this invisibility. In many respects, it builds on work by a number of scholars who have begun to interrogate the criminal justice and social discourses surrounding violent crime, primarily sexual violence, and who problematize these discourses (see for example Carmody 2003; Carmody and Carrington 2000; Marcus 1992). It will begin by outlining these dominant discourses, and then problematize these by identifying some of the important differences between LGBTI IPV and IPV in heterosexual relationships. In doing so, this chapter will suggest some possible reasons for the silence regarding IPV in LGBTI relationships, and the effects that this can have on victims. Although an equally important area of research, and another point at which the limitations of dominant social discourses surrounding IPV can be brought to light, this chapter will not examine violence experienced by heterosexual men at the hands of their intimate female partners. Instead, it will restrict itself to IPV perpetrated within same-sex relationships.

Queering cyberspace : fan fiction communities as spaces for expressing and exploring sexuality

The social construction of sexuality over the past one hundred and fifty years has created a dichotomy between heterosexual and non-heterosexual identities that essentially positions the former as “normal” and the latter as deviant. Even Kinsey’s and others’ work on the continuum of sexualities did little to alter the predominantly heterosexist perception of the non-heterosexual as “other” (Kinsey, Pomeroy and Martin 2007; Esterberg 2006; Franceour and Noonan 2007). Some political action and academic work is beginning to challenge such perceptions. Even some avenues of social interaction, such as the recent proliferation of online communities, may also challenge such views, or at least contribute to their being rethought in some ways. This chapter explores a specific kind of online community devoted to fan fiction, specifically homoerotic – or what is known colloquially as “slash” – fan fiction. Fan fiction is fiction, published on the internet, and written by fans of well-known books and television shows, using the characters to create new and varied plots. “Slash” refers to the pairing of two of the male characters in a romantic relationship, and the term comes from the punctuation mark dividing the named pair as, for example, Spock/Kirk from the Star Trek television series. Although there are some slash fan-fiction stories devoted to female-female relationships – called “femmeslash” – the term “slash” generally refers to male-male relationships, and will be utilized throughout this chapter, given that the research discussed focuses on communities centered around one such male pairing.

Positioning public relations as an academic discipline in Australia

Academic public relations in Australia appears to be entering a new phase in its relatively short history. The early model, in which tertiary courses were confined to teaching – focused institutions and conducted largely by teacher-practitioners, is being supplanted by one in which the discipline is now offered in most Australian universities, is increasingly embracing research, and is being taught by staff following more traditional academic career paths. Despite the formal association with the communication discipline through Australian and New Zealand Communication Association, public relations academics have increasingly asserted the independence of their discipline and in reality have very little dialogue with the other strands of the communication discipline. These developments call into question the most appropriate knowledge base for public relations as an academic discipline in Australia and its proper relation to the profession (and the Public Relations Institute of Australia as the professional body). One danger associated with the assertion of disciplinary independence lies in the risk of excessive reliance on a relatively narrow body of work emanating from the more established United States public relations academy, in the process ignoring much richer work in surrounding disciplines such as social theory, rhetoric, organisation communication, and business and society. The emphasis on disciplinary demarcation also seems curious during a time of growing ‘interdisciplinarity’ in the humanities and the social sciences. This paper critically reviews the construction of public relations as an academic discipline in Australia, drawing on some of the literature on academic disciplinarity to propose a repositioning of the discipline, one that is less focused on asserting difference than on finding connections with other bodies of knowledge while maintaining close links with professional practice.

Impacts of periodic tillage on soil C stocks : a synthesis

Long-term loss of soil C stocks under conventional tillage and accrual of soil C following adoption of no-tillage have been well documented. No-tillage use is spreading, but it is common to occasionally till within a no-till regime or to regularly alternate between till and no-till practices within a rotation of different crops. Short-term studies indicate that substantial amounts of C can be lost from the soil immediately following a tillage event, but there are few field studies that have investigated the impact of infrequent tillage on soil C stocks. How much of the C sequestered under no-tillage is likely to be lost if the soil is tilled? What are the longer-term impacts of continued infrequent no-tillage? If producers are to be compensated for sequestering C in soil following adoption of conservation tillage practices, the impacts of infrequent tillage need to be quantified. A few studies have examined the short-term impacts of tillage on soil C and several have investigated the impacts of adoption of continuous no-tillage. We present: (1) results from a modeling study carried out to address these questions more broadly than the published literature allows, (2) a review of the literature examining the short-term impacts of tillage on soil C, (3) a review of published studies on the physical impacts of tillage and (4) a synthesis of these components to assess how infrequent tillage impacts soil C stocks and how changes in tillage frequency could impact soil C stocks and C sequestration. Results indicate that soil C declines significantly following even one tillage event (1-11 % of soil C lost). Longer-term losses increase as frequency of tillage increases. Model analyses indicate that cultivating and ripping are less disruptive than moldboard plowing, and soil C for those treatments average just 6% less than continuous NT compared to 27% less for CT. Most (80%) of the soil C gains of NT can be realized with NT coupled with biannual cultivating or ripping. (C) 2007 Elsevier B.V. All rights reserved.