A genetic assessment of parentage in the blackspot sergeant damselfish, Abudefduf sordidus (Pisces: Pomacentridae)

Microsatellite markers were used to investigate the reproductive behavior of the damselfish Abudefduf sordidus at Johnston Atoll, Central Pacific Ocean. Genetic results indicated that ten males maintained guardianship over their nest territories for up to nine nest cycles during a 3.5 month period. Genotypes of 1025 offspring sampled from 68 nests (composed of 129 clutches) were consistent with 95% of the offspring being sired by the guardian male. Offspring lacking paternal alleles at two or more loci were found in 19 clutches, indicating that reproductive parasitism and subsequent alloparental care occurred. Reconstructed maternal genotypes allowed the identification of a minimum of 74 different females that spawned with these ten territorial males. Males were polygynous, mating with multiple females within and between cycles. Genetic data from nests, which consisted of up to four clutches during a reproductive cycle, indicated that each clutch usually had only one maternal contributor and that different clutches each had different dams. Females displayed sequential polyandry spawning with one male within a cycle but switched males in subsequent spawning cycles. These results highlight new findings regarding male parasitic spawning, polygyny, and sequential polyandry in a marine fish with exclusive male paternal care.Published versio

The Endothelium: The Vascular Information Exchange

Maintenance of adequate blood flow to tissues and organs requires that endothelial cells dynamically respond in a stimulus-specific manner to elicit appropriate changes in smooth muscle contractility and thus, arterial diameter. Endothelial cells can be stimulated directly by increases in blood flow and by humoral factors acting on surface receptors, as well as through flux of second messengers from smooth muscle cells activated by release of neurotransmitters from perivascular nerves. The ability of endothelial cells to generate stimulus-specific responses to these diverse inputs is facilitated by organization of ion channels and signaling proteins into microdomains that permit finely-tuned, spatially-restricted Ca2+ events to differentially activate key effectors such as nitric oxide (NO) synthase and Ca2+-activated K+ (KCa) channels. NO is a diffusible mediator which acts locally to cause vasodilation. Opening of KCa channels causes hyperpolarization of the endothelial membrane potential which spreads to surrounding smooth muscle cells to also cause local vasodilation. However, once initiated, hyperpolarization also spreads longitudinally through the endothelium to effect coordinated changes in blood flow within multiple arterial segments. Thus, the signaling pathways activated by a particular stimulus determine whether it’s effects on arterial diameter are localized or can impact blood flow at the level of the vascular bed

The United Arab Emirates Nuclear Program and Proposed U.S. Nuclear Cooperation

This report provides background information on the UAE nuclear program, reviews developments to date, analyzes proposed nuclear cooperation with the United States, and discusses relevant legislative proposals and options

Magneto-optical Kerr Effect Studies of Square Artificial Spin Ice

We report a magneto-optical Kerr effect study of the collective magnetic response of artificial square spin ice, a lithographically-defined array of single-domain ferromagnetic islands. We find that the anisotropic inter-island interactions lead to a non-monotonic angular dependence of the array coercive field. Comparisons with micromagnetic simulations indicate that the two perpendicular sublattices exhibit distinct responses to island edge roughness, which clearly influence the magnetization reversal process. Furthermore, such comparisons demonstrate that disorder associated with roughness in the island edges plays a hitherto unrecognized but essential role in the collective behavior of these systems.Comment: Physical Review B, Rapid Communications (in press

Clinical and service implications of a cognitive analytic therapy model of psychosis

Cognitive analytic therapy (CAT) is an integrative, interpersonal model of therapy predicated on a radically social concept of self, developed over recent years in the UK by Anthony Ryle. A CAT-based model of psychotic disorder has been developed much more recently based on encouraging early experience in this area. The model describes and accounts for many psychotic experiences and symptoms in terms of distorted, amplified or muddled enactments of normal or ‘neurotic’ reciprocal role procedures (RRPs) and of damage at a meta-procedural level to the structures of the self. Reciprocal role procedures are understood in CAT to represent the outcome of the process of internalization of early, sign-mediated, interpersonal experience and to constitute the basis for all mental activity, normal or otherwise. Enactments of maladaptive RRPs generated by early interpersonal stress are seen in this model to constitute a form of ‘internal expressed emotion’. Joint description of these RRPs and their enactments (both internally and externally) and their subsequent revision is central to the practice of CAT during which they are mapped out through written and diagrammatic reformulations. This model may usefully complement and extend existing approaches, notably recent CBT-based interventions, particularly with ‘difficult’ patients, and generate meaningful and helpful understandings of these disorders for both patients and their treating teams. We suggest that use of a coherent and robust model such as CAT could have important clinical and service implications in terms of developing and researching models of these disorders as well as for the training of multidisciplinary teams in their effective treatment

Pleasure and pedagogy: the consumption of DVD add-ons among Irish teenagers

This article addresses the issue of young people and media use in the digital age, more specifically the interconnection between new media pleasures and pedagogy as they relate to the consumption of DVD add-ons. Arguing against the view of new media as having predominantly detrimental effects on young people, the authors claim that new media can enable young people to develop media literacy skills and are of the view that media literacy strategies must be based on an understanding and legitimating of young people's use patterns and pleasures. The discussion is based on a pilot research project on the use patterns and pleasures of use with a sample of Irish teenagers. They found that DVDs were used predominantly in the home context, and that, while there was variability in use between the groups, overall they developed critical literacy skills and competences which were interwoven into their social life and projects of identity construction. The authors suggest that these findings could be used to develop DVDs and their add-on features as a learning resource in the more formal educational setting and they go on to outline the potential teaching benefits of their use across a range of pedagogical areas

Visfatin reduces gap junction mediated cell-to-cell communication in proximal tubule-derived epithelial cells

Aim: Associated with obesity, visfatin may have a role in the pathogenesis of diabetic nephropathy in type II diabetes. This study identifies a link between the visfatin, TGF-β1 and reduced cell-to-cell coupling in proximal tubule derived epithelial cells. Methods: Western blot analysis confirmed changes in expression of connexins Cx26, Cx40 and Cx43 in HK2-cells +/- visfatin &/or TGF-β1. Visfatin evoked increases in TGF-β1 secretion were determined by ELISA, and functional intercellular communication assessed via Lucifer yellow dye transfer and paired-whole cell patch clamp electrophysiology. Results: Visfatin (10, 100 and 200ng/mL) decreased expression of Cx26 to 58±11%, 40± 3% and 21±2% and Cx43 to 73±5%, 44± 4% and 29±6% as compared to control at 48hrs (n=3; P<0.01). The effects were not dependent on changes in membrane integrity, cytotoxicity or cell viability as assessed by MTT, crystal-violet and lactate-dehydrogenase assays. Expression of Cx40 was unaffected by the adipocytokine. Visfatin (200ng/ml) increased TGF-β1 secretion by 154% of control (n=3; p<0.01). Visfatin-evoked changes in Cx26 and Cx43 expression were mimicked by exogenous application of TGF-β1 (2-10ng/ml, p<0.001 n=3). Visfatin reduced dye transfer between coupled-cells and decreased functional conductance by 63% as compared to control (n=6; p<0.01). Conclusions: Visfatin reduced connexin expression in HK2-cells, an effect mirrored by a loss in functional conductance between coupled cells. Visfatin increased TGF-β secretion and the pattern of change for connexin expression was mimicked by exogenous application of the pro-fibrotic cytokine. These data suggest that visfatin reduces connexin-mediated intercellular communication in proximal tubule-derived epithelial cells via a TGF-β dependent pathway. This work is supported by a grant from Diabetes UK (BDA: 11/0004215)

Curriculum implementation exploratory studies: Final report

Throughout the history of schooling in New Zealand the national curriculum has been revised at fairly regular intervals. Consequently, schools are periodically faced with having to accommodate to new curriculum. In between major changes other specifically-focused changes may arise; for example, the increased recent emphasis upon numeracy and literacy

Filling the gap - COI barcode resolution in eastern Palearctic birds

© 2009 Kerr et al; licensee BioMed Central Ltd. This is an Open Access article distributed under the terms of the Creative Commons Attribution Licens