Mechanistic studies of copper and thiolate ion induced s-nitrosothiol decompositions

A detailed study concerning the aqueous decomposition characteristics of S-nitrosothiols in both the presence and absence of cupric ions was undertaken. Spectrophotometric measurements established that the true catalytic species generating nitric oxide from S-nitrosothiols is Cu(^+), formed by the reduction of copper(II) ions by thiolate, which is present as an impurity in solution. Introduction of the specific cuprous ion chelator neocuproine inhibited reaction, with the concentration of thiol in situ having a significant influence on the absorbance/time traces obtained. Under certain conditions thiolate ions clearly promoted S-nitrosothiol decomposition, whereas at times an opposite effect was noted. These results have been correlated with the reductive ability and chelation properties towards Cu(^2+) of each thiol in question. Structure/reactivity studies were extended further to include a range of S-nitrosated aromatic and heterocyclic thiols which generated the corresponding disulfides in distilled water yet reformed the appropriate thione at pH 7.4, along with nitric oxide in both media. A mechanism has been proposed which accounts for these observations. The reaction of S-nitrosothiols with cupric ions bound to biologically significant molecules such as amino acids, peptides and proteins was followed. Despite Cu(^2+) being chelated in this manner, S-nitrosothiol decomposition was apparent, albeit at a slower rate than that seen when copper(II) sulfate pentahydrate was utilised. Thiolate ions were capable of reducing Cu(^2+) Cu(^+) which was bound to such molecules suggesting a possible mechanism for nitric oxide formation from S-nitrosothiols in vivo. The blue copper protein ceruloplasmin also promoted NO generation under physiological conditions. A brief investigation into the direct reaction of thiolate ion with its corresponding S-nitrosothiol was also carried out. It was discovered that the major reaction product in this instance is ammonia and not nitric oxide, suggesting that a different copper-ion independent process is occurring involving direct interaction between the two species

The Effect of Motivational Highlight DVDs on State Self-Confidence in Elite Female Hockey Players

Formal coach education programmes, driven by the national governing bodies of individual sports, have for many years been regarded as essential in the development of competent, qualified coaches. However, more recent opinion suggests that such coach education is actually ‘‘low impact’’ in comparison to the hours individual aspirant coach’s spend coaching, being coached or participating (Rossi & Cassidy, 1999: Learning and teaching in physical education. London: Falmer). It appears the literature is, in part, implying that experiential learning has greater significance over formal education programmes. The aim of this study was to investigate the educational journey of a sample of paddlesport coaches by addressing why coaches chose to enter formal coach education programmes

Stably free modules over virtually free groups

Let $F_m$ be the free group on $m$ generators and let $G$ be a finite nilpotent group of non square-free order; we show that for each $m\ge 2$ the integral group ring ${\bf Z}[G\times F_m]$ has infinitely many stably free modules of rank 1.Comment: 9 pages. The final publication is available at http://www.springerlink.com doi:10.1007/s00013-012-0432-

Analysis of Risk Identification and Relationships for Major Engineering and Construction Transportation Projects

Risk management has been integrated into transportation infrastructure construction projects for more than two decades. Risk management seeks to identify possible events that could impact the performance of a project, and allow the project team to influence those events to either reduce the severity of negative possibilities or increase the severity of positive possibilities. Construction risk management literature has focused on each step of the risk management process with the aim of making the next incremental improvement in project performance. Researchers focusing on risk identification have done so primarily by proposing different categorization schemes and the primary factors on which project teams should place their focus. While these studies introduce an important starting point for project managers, they nearly always start with identification of risk factors through a literature review, and measure importance through some version of an expert survey or questionnaire. This approach lacks sufficient rigor as it relies on the evaluation of risks facing hypothetical projects in the abstract. Additionally, the relationship between risk factors is often ignored under the assumption that each risk is independent. Further, there is no existing research addressing the disconnect between risk identification tools and the inability to identify risks in practice. This dissertation provides a comprehensive examination of the risks facing State Transportation Agencies (STA) and the challenges in identifying those risks. Content analysis of more than 5000 risk statements from 289 transportation construction projects revealed 34 common risk factors. The risk factors were reviewed by industry professionals and compared with the factors frequently mentioned in the literature. Additionally, the risks were examined for their relationships to other risks, leading to the identification of 60 significant relationships among the risk factors. The risk relationships were determined by examining the sentiment within risk statements and whether they were identified together in the same project, and validated by a panel of risk practitioners. The final study included 12 interviews with professionals managing one or more projects that experienced incomplete risk identification. The study identified 10 contributing factors through a thematic analysis of the interviews including cognitive biases, communication and alignment, facilitator expertise, imagination, experience, level of detail, management support, process standardization, stakeholder participation, and time constraints. The findings of this dissertation contribute to the body of knowledge in construction risk management. It is the largest empirical study of risk registers, identifying the most common risk factors and their relationships. The findings also have practical implications for public agencies managing transportation infrastructure projects.</p

Ribosomal DNA sequence heterogeneity reflects intraspecies phylogenies and predicts genome structure in two contrasting yeast species

The ribosomal RNA encapsulates a wealth of evolutionary information, including genetic variation that can be used to discriminate between organisms at a wide range of taxonomic levels. For example, the prokaryotic 16S rDNA sequence is very widely used both in phylogenetic studies and as a marker in metagenomic surveys and the internal transcribed spacer region, frequently used in plant phylogenetics, is now recognized as a fungal DNA barcode. However, this widespread use does not escape criticism, principally due to issues such as difficulties in classification of paralogous versus orthologous rDNA units and intragenomic variation, both of which may be significant barriers to accurate phylogenetic inference. We recently analyzed data sets from the Saccharomyces Genome Resequencing Project, characterizing rDNA sequence variation within multiple strains of the baker's yeast Saccharomyces cerevisiae and its nearest wild relative Saccharomyces paradoxus in unprecedented detail. Notably, both species possess single locus rDNA systems. Here, we use these new variation datasets to assess whether a more detailed characterization of the rDNA locus can alleviate the second of these phylogenetic issues, sequence heterogeneity, while controlling for the first. We demonstrate that a strong phylogenetic signal exists within both datasets and illustrate how they can be used, with existing methodology, to estimate intraspecies phylogenies of yeast strains consistent with those derived from whole-genome approaches. We also describe the use of partial Single Nucleotide Polymorphisms, a type of sequence variation found only in repetitive genomic regions, in identifying key evolutionary features such as genome hybridization events and show their consistency with whole-genome Structure analyses. We conclude that our approach can transform rDNA sequence heterogeneity from a problem to a useful source of evolutionary information, enabling the estimation of highly accurate phylogenies of closely related organisms, and discuss how it could be extended to future studies of multilocus rDNA systems. [concerted evolution; genome hydridisation; phylogenetic analysis; ribosomal DNA; whole genome sequencing; yeast]

The bereavement experiences of families of potential organ donors:a qualitative longitudinal case study illuminating opportunities for family care

OBJECTIVES: To illuminate opportunities for care in the context of deceased organ donation by exploring pre-existing family and healthcare professional characteristics, in-hospital experiences, and ongoing adjustment through the lenses of grief theory, systems theory, meaning-making, narrative, and organ donation literature. METHOD: Qualitative longitudinal case studies explored individual and family change in five Australian families who had consented to Donation after Circulatory Determination of Death at a single centre. Participants attended semi-structured interviews at four, eight, and twelve months after the death. FINDINGS: Family values, pre-existing relationships, and in-hospital experiences influenced first responses to their changed lives, understanding of the patient’s death, and ongoing family adjustment. Novel behaviour that was conguent with family values was required at the hospital, especially if the patient had previously played a key role in family decision-making. This behaviour and emerging interactional patterns were drawn into family life over the first year of their bereavement. RECOMMENDATIONS: Training that includes lenses introduced in this study will enable healthcare professionals to confidently respond to individual and family psychosocial needs. CONCLUSION: The lenses of grief theory and systems thinking highlight opportunities for care tailored to the unique in-hospital context and needs that emerge in the months that follow

Management and drivers of change of pollinating insects and pollination services. National Pollinator Strategy: for bees and other pollinators in England, Evidence statements and Summary of Evidence

These Evidence Statements provide up-to-date information on what is known (and not known) about the status, values, drivers of change, and responses to management of UK insect pollinators (as was September 2018). This document has been produced to inform the development of England pollinator policy, and provide insight into the evidence that underpins policy decision-making. This document sits alongside a more detailed Summary of Evidence (Annex I) document written by pollinator experts. For information on the development of the statements, and confidence ratings assigned to them, please see section ‘Generation of the statements’ below. Citations for these statements are contained in the Summary of Evidence document

On the structure of eigenfunctions corresponding to embedded eigenvalues of locally perturbed periodic graph operators

The article is devoted to the following question. Consider a periodic self-adjoint difference (differential) operator on a graph (quantum graph) G with a co-compact free action of the integer lattice Z^n. It is known that a local perturbation of the operator might embed an eigenvalue into the continuous spectrum (a feature uncommon for periodic elliptic operators of second order). In all known constructions of such examples, the corresponding eigenfunction is compactly supported. One wonders whether this must always be the case. The paper answers this question affirmatively. What is more surprising, one can estimate that the eigenmode must be localized not far away from the perturbation (in a neighborhood of the perturbation's support, the width of the neighborhood determined by the unperturbed operator only). The validity of this result requires the condition of irreducibility of the Fermi (Floquet) surface of the periodic operator, which is expected to be satisfied for instance for periodic Schroedinger operators.Comment: Submitted for publicatio

Monitoring interval-training responses for swimming using the 3-min all-out exercise test.

International Journal of Exercise Science 9(5): 545-553, 2016. The purpose of this study was to determine whether the 3-min all-out exercise test (3MT) could be applied to create an off-season high intensity, interval training (HIIT) program to improve performance, specifically critical velocity (CV), in the sport of swimming. We tested a group of competitive female swimmers (age = 19 ± 1 yrs, height = 169 ± 7 cm, body mass = 69 ± 9 kg) to determine their swimming CV and finite energy capacity \u3eCV (D’), and created a four week (2 d∙wk-1) personalized interval training program. Participants were divided in to two groups, a 150yd interval group (n =11) and a 250yd interval group (n =6). Each group completed a series of intervals designed to deplete a given percentage of D’ at velocities exceeding CV. A 3MT following the training period was administered to assess for any changes in CV, D’, average velocity during the first 150s of the test (V150s) and total distance traveled (D). Both groups improved their CV (+0.04 m∙s-1), V150s (+0.03 m∙s-1) and D (+8.64 m) (p \u3c 0.05), however, significant interactions for D’ between groups was not observed (p \u3e 0.05). We conclude that HIIT prescriptions based on a 3MT can improve swim performance over a four-week period. Future research on the fidelity of measuring CV and D’ using a swimming 3MT is needed to help aid practitioners in interpreting true training adaptations