964 resultados para Graham, Dan


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In the structure of the title compound, C6H13N2O+ C8H7O2- . 0.5H2O, the asymmetric unit comprises two isonipecotamide cations, two phenylacetate anions and a water molecule of solvation. The hydrogen-bonding environments for both sets of ion pairs are essentially identical with the piperidinium and amide 'ends' of each cation involved in lateral heteromolecular hydrogen-bonded cyclic N---H...O associations [graph set R2/2(11)] which incorporate a single carboxyl O-atom acceptor. These cyclic motifs enclose larger R5/5(21) cyclic systems forming sheet substructures which lie parallel to (101) and are linked across b by the single water molecule via water O---H...O(carboxyl) associations to give a two-dimensional duplex-sheet structure

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The structures of the anhydrous 1:1 proton-transfer compounds of isonipecotamide (4-carbamoylpiperidine) with picric acid and 3,5-dinitrosalicylic acid, namely 4-carbamoylpiperidinium 2,4,6-trinitrophenolate, C6H13N2O8+ C6H2N3O7- (I) and 4-carbamoylpiperidinium 2-carboxy-4,6-dinitrophenolate, C6H13N2O8+ C7H3N2O7-: two forms, the monoclinic alpha-polymorph (II) and the triclinic beta-polymorph (III) have been determined at 200 K. All compounds form hydrogen-bonded structures, one-dimensional in (II), two-dimensional in (I) and three-dimensional in (III). In (I), the cations form centrosymmetric cyclic head-to-tail hydrogen-bonded homodimers [graph set R2/2(14)] through lateral duplex piperidinium N---H...O(amide) interactions. These dimers are extended into a two-dimensional network structure through further interactions with anion phenolate-O and nitro-O acceptors, including a direct symmetric piperidinium N-H...O(phenol),O(nitro) cation--anion association [graph set R2/1(6)]. The monoclinic polymorph (II) has a similar R2/1(6) cation-anion hydrogen-bonding interaction to (I) but with an additional conjoint symmetrical R1/2(4) interaction as well as head-to-tail piperidinium N-H...O(amide) O hydrogen bonds and amide N-H...O(carboxyl) hydrogen bonds, give a network structure which include large R3/4(20) rings. The hydrogen bonding in the triclinic polymorph (III) is markedly different from that of monoclinic (II). The asymmetric unit contains two independent cation-anion pairs which associate through cyclic piperidinium N-H...O,O'(carboxyl) interactions [graph set R2/1(4)]. The cations also show the zig-zag head-to-tail piperidinium N-H...O(amide) hydrogen-bonded chain substructures found in (II) but in addition feature amide N-H...O(nitro) and O(phenolate) and amide N-H...O(nitro) associations. As well there is a centrosymmetric double-amide N-H...O(carboxyl) bridged bis(cation-anion) ring system [graph set R2/4(8)] in the three-dimensional framework. The structures reported here demonstrate the utility of the isonipecotamide cation as a synthon with previously unrecognized potential for structure assembly applications. Furthermore, the structures of the two polymorphic 3,5-dinitrosalicylic acid salts show an unusual dissimilarity in hydrogen-bonding characteristics, considering that both were obtained from identical solvent systems.

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The structures of the anhydrous 1:1 proton-transfer compounds of isonipecotamide (piperidine-4-carboxamide) with the three isomeric mononitro-substituted benzoic acids and 3,5-dinitrobenzoic acid, namely 4-carbamoylpiperidinium 2-nitrobenzoate (I), 4-carbamoylpiperidinium 3-nitrobenzoate (II), 4-carbamoylpiperidinium 4-nitrobenzoate (III), (C6H13N2O+ C7H4NO4-) and 4-carbamoylpiperidinium 3,5-dinitrobenzoate (IV) (C6H13N2O+ C7H5N2O6-)respectively, have been determined at 200 K. All salts form hydrogen-bonded structures: three-dimensional in (I), two-dimensional in (II) and (III) and one-dimensional in (IV). Featured in the hydrogen bonding of three of these [(I), (II) and (IV)] is the cyclic head-to-head amide--amide homodimer motif [graph set R2/2~(8)] through a duplex N---H...O association, the dimer then giving structure extension via either piperidinium or amide H-donors and carboxylate-O and in some examples [(II) and (IV)], nitro-O atom acceptors. In (I), the centrosymmetric amide-amide homodimers are expanded laterally through N-H...O hydrogen bonds via cyclic R2/4(8) interactions forming ribbons which extend along the c cell direction. These ribbons incorporate the 2-nitrobenzoate cations through centrosymmetric cyclic piperidine N-H...O(carboxyl) associations [graph set R4/4(12)], giving inter-connected sheets in the three-dimensional structure. In (II) in which no amide-amide homodimer is present, duplex piperidinium N-H...O(amide) hydrogen-bonding homomolecular associations [graph set R2/2(14)] give centrosymmetric head-to-tail dimers. Structure extension occurs through hydrogen-bonding associations between both the amide H-donors and carboxyl and nitro O-acceptors as well as a three-centre piperidinium N-H...O,O'(carboxyl) cyclic R2/1(4) association giving the two-dimensional network structure. In (III), the centrosymmetric amide-amide dimers are linked through the two carboxyl O-atom acceptors of the anions via bridging piperidinium and amide N-H...O,O'...H-N(amide) hydrogen bonds giving the two-dimensional sheet structure which features centrosymmetric cyclic R4/4(12) associations. In (IV), the amide-amide dimer is also centrosymmetric with the dimers linked to the anions through amide N-H...O(nitro) interactions. The piperidinium groups extend the structure into one-dimensional ribbons via N-H...O(carboxyl) hydrogen bonds. The structures reported here further demonstrate the utility of the isonipecotamide cation in molecular assembly and highlight the efficacy of the cyclic R2/2(8) amide-amide hydrogen-bonding homodimer motif in this process and provide an additional homodimer motif type in the head-to-tail R2/2(14) association.

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Music is inherently active and interactive. Like technologies before them, digital systems provide a range of enhanced music performance opportunities. In this paper we outline the educational advantages of ensemble performance in which generative media systems are integrated. As a concrete example, we focus on our work with the jam2jam system which uses generative music processes to enhance collaborative music making. We suggest that our research points toward a new class of activities that maintain the well established benefits of ensemble performance while adding cultural and pedagogical value by leveraging the capabilities and cachet of digital media practices.

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This chapter advocates a pedagogy where relationships form the basis for developing curricular and pedagogical ways of being with students. A relational pedagogy begins through considering the broad questions of: Where are music and technology in the lives the teacher and student? Where do adolescents make meaning through music and technology? How can teachers develop a community with their students through music and technology? We argue that relationships should be placed at the center of pedagogical and curricular decision-making. Through this approach, music educators are better equipped to make space for and honor student agency and learning through harnessing the ways adolescents intuitively engage with music and technology.

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BACKGROUND: The relationship between cigarette smoking and cardiovascular disease is well established, yet the underlying mechanisms remain unclear. Although smokers have a more atherogenic lipid profile, this may be mediated by other lifestyle-related factors. Analysis of lipoprotein subclasses by the use of nuclear magnetic resonance spectroscopy (NMR) may improve characterisation of lipoprotein abnormalities. OBJECTIVE: We used NMR spectroscopy to investigate the relationships between smoking status, lifestyle-related risk factors, and lipoproteins in a contemporary cohort. METHODS: A total of 612 participants (360 women) aged 40–69 years at baseline (199021994) enrolled in the Melbourne Collaborative Cohort Study had plasma lipoproteins measured with NMR. Data were analysed separately by sex. RESULTS: After adjusting for lifestyle-related risk factors, including alcohol and dietary intake, physical activity, and weight, mean total low-density lipoprotein (LDL) particle concentration was greater for female smokers than nonsmokers. Both medium- and small-LDL particle concentrations contributed to this difference. Total high-density lipoprotein (HDL) and large-HDL particle concentrations were lower for female smokers than nonsmokers. The proportion with low HDL particle number was greater for female smokers than nonsmokers. For men, there were few smoking-related differences in lipoprotein measures. CONCLUSION: Female smokers have a more atherogenic lipoprotein profile than nonsmokers. This difference is independent of other lifestyle-related risk factors. Lipoprotein profiles did not differ greatly between male smokers and nonsmokers.

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There has been a remarkable expansion in the use of executive coaching as an executive development technique over the past two decades. The widespread popularity of executive coaching has been based largely on anecdotal feedback regarding its effectiveness. The small body of empirical research has been growing but conclusive outcomes are rare. This investigation has focused on the factors of executive coaching that contribute to its effectiveness with the perceptions of both executives and coaches being sought. Six major themes were identified, each comprising a collection of meanings. The findings of this study add value to the field by identifying factors contributing to coaching effectiveness, and providing for the coaching practitioner a basis for enhancing their practice of executive coaching.

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Changes in stride characteristics and gait rhythmicity characterize gait in Parkinson's disease and are widely believed to contribute to falls in this population. However, few studies have examined gait in PD patients who fall. This study reports on the complexities of walking in PD patients who reported falling during a 12-month follow-up. Forty-nine patients clinically diagnosed with idiopathic PD and 34 controls had their gait assessed using three-dimensional motion analysis. Of the PD patients, 32 (65%) reported at least one fall during the follow-up compared with 17 (50%) controls. The results showed that PD patients had increased stride timing variability, reduced arm swing and walked with a more stooped posture than controls. Additionally, PD fallers took shorter strides, walked slower, spent more time in double-support, had poorer gait stability ratios and did not project their center of mass as far forward of their base of support when compared with controls. These stride changes were accompanied by a reduced range of angular motion for the hip and knee joints. Relative to walking velocity, PD fallers had increased mediolateral head motion compared with PD nonfallers and controls. Therefore, head motion could exceed “normal” limits, if patients increased their walking speed to match healthy individuals. This could be a limiting factor for improving gait in PD and emphasizes the importance of clinically assessing gait to facilitate the early identification of PD patients with a higher risk of falling.

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The rise to prominence of citizen journalism is usually described as a paradigm shift in the relationship between news organizations and their audiences – ‘citizen’ or ‘amateur’ journalists are positioned as inherently different from, and possibly in competition with, ‘professional’ journalists. Some journalists in the industry have taken up this theme, and are at pains to distinguish their professional, supposedly objective and accountable practices from what they describe as the opinionated and partisan ‘armchair journalism’ of amateurs, while some citizen journalists, in turn, give as good at they get and describe the professionals as lackeys of their corporate masters who (willingly or unwittingly) fall prey to political and commercial spin. In fact, the very terminology we use to describe both sides creates the impression that professionals are not also citizens, and that citizen journalists are incapable of having professional skills and knowledges; in reality, of course, the lines between them are much less clear.

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Purpose: To analyze the repeatability of measuring nerve fiber length (NFL) from images of the human corneal subbasal nerve plexus using semiautomated software. Methods: Images were captured from the corneas of 50 subjects with type 2 diabetes mellitus who showed varying severity of neuropathy, using the Heidelberg Retina Tomograph 3 with Rostock Corneal Module. Semiautomated nerve analysis software was independently used by two observers to determine NFL from images of the subbasal nerve plexus. This procedure was undertaken on two occasions, 3 days apart. Results: The intraclass correlation coefficient values were 0.95 (95% confidence intervals: 0.92–0.97) for individual subjects and 0.95 (95% confidence intervals: 0.74–1.00) for observer. Bland-Altman plots of the NFL values indicated a reduced spread of data with lower NFL values. The overall spread of data was less for (a) the observer who was more experienced at analyzing nerve fiber images and (b) the second measurement occasion. Conclusions: Semiautomated measurement of NFL in the subbasal nerve fiber layer is highly repeatable. Repeatability can be enhanced by using more experienced observers. It may be possible to markedly improve repeatability when measuring this anatomic structure using fully automated image analysis software.

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Driver aggression is an increasing concern for motorists, with some research suggesting that drivers who behave aggressively perceive their actions as justified by the poor driving of others. Thus attributions may play an important role in understanding driver aggression. A convenience sample of 193 drivers (aged 17-36) randomly assigned to two separate roles (‘perpetrators’ and ‘victims’) responded to eight scenarios of driver aggression. Drivers also completed the Aggression Questionnaire and Driving Anger Scale. Consistent with the actor-observer bias, ‘victims’ (or recipients) in this study were significantly more likely than ‘perpetrators’ (or instigators) to endorse inadequacies in the instigator’s driving skills as the cause of driver aggression. Instigators were significantly more likely attribute the depicted behaviours to external but temporary causes (lapses in judgement or errors) rather than stable causes. This suggests that instigators recognised drivers as responsible for driving aggressively but downplayed this somewhat in comparison to ‘victims’/recipients. Recipients and instigators agreed that the behaviours were examples of aggressive driving but instigators appeared to focus on the degree of intentionality of the driver in making their assessments while recipients appeared to focus on the safety implications. Contrary to expectations, instigators gave mean ratings of the emotional impact of driving aggression on recipients that were higher in all cases than the mean ratings given by the recipients. Drivers appear to perceive aggressive behaviours as modifiable, with the implication that interventions could appeal to drivers’ sense of self-efficacy to suggest strategies for overcoming plausible and modifiable attributions (e.g. lapses in judgement; errors) underpinning behaviours perceived as aggressive.

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There has been uncertainty regarding the precise role that the pocket protein Rb1 plays in murine melanocyte homeostasis. It has been reported that the TAT-Cre mediated loss of exon 19 from a floxed Rb1 allele causes melanocyte apoptosis in vivo and in vitro. This is at variance with other findings showing, either directly or indirectly, that Rb1 loss in melanocytes has no noticeable effect in vivo, but in vitro leads to a semi-transformed phenotype. In this study, we show that Rb1-null melanocytes lacking exon 19 do not undergo apoptosis and survive both in vitro and in vivo, irrespective of the developmental stage at which Cre-mediated ablation of the exon occurs. Further, Rb1 loss has no serious long-term ramifications on melanocyte homeostasis in vivo, with Rb1-null melanocytes being detected in the skin after numerous hair cycles, inferring that the melanocyte stem cell population carrying the Cre-mediated deletion is maintained. Consequently, whilst Rb1 loss in the melanocyte is able to alter cellular behaviour in vitro, it appears inconsequential with respect to melanocyte homeostasis in the mouse skin.

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Issues and Approach: The high rates of co-occurring depression and substance use, and the negative impact of this on illness course and outcomes have been well established. Despite this, few clinical trials have examined the efficacy of cognitive behaviour therapy (CBT). This paper systematically reviews these clinical trials, with an aim of providing recommendations for how future research can develop a more robust evidence base for the treatment of these common comorbidities. Leading electronic databases, including PubMed (ISI) and PsychINFO (CSA), were searched for peer-reviewed journal articles using CBT for the treatment of co-occurring depression and substance use. Of the 55 articles identified, 12 met inclusion criteria and were included in the review. ---------- Key Findings: There is only a limited evidence for the effectiveness of CBT either alone or in combination with antidepressant medication for the treatment of co-occurring depression and substance use. While there is support for the efficacy of CBT over no treatment control conditions, there is little evidence that CBT is more efficacious than other psychotherapies. There is, however, consistent evidence of improvements in both depression and substance use outcomes, regardless of the type of treatment provided and there is growing evidence that that the effects of CBT are durable and increase over time during follow up. ---------- Conclusions. Rather than declaring the ‘dodo bird verdict’ that CBT and all other psychotherapies are equally efficacious, it would be more beneficial to develop more potent forms of CBT by identifying variables that mediate treatment outcomes.

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The relationship between culture and the economy is of growing interest to researchers, writers and policy makers. Advanced economies have become increasingly ‘culturalised’, pushing culture from the periphery to the centre of policy concerns and action. The economic downturn commencing in late 2008 generated predictions that ranged from the apocalyptic to the sanguine, across all sectors. This article offers an insight into the relationship between the economy, the creative industries and their geographic localities. It investigates creative industries situated away from the urban core, and located in the outer suburbs of Melbourne and Brisbane. We suggest that for creative industries situated in outer suburbs, there are characteristics that may contribute to their economic resilience.

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In the structure of the title compound, C6H13N2O+ C7H4NO5-, the isonipecotamide cations and the 5-nitrosalicylate anions form hydrogen-bonded chain substructures through head-to-tail piperidinium N---H...O(carboxyl) hydrogen bonds and through centrosymmetric cyclic head-to-head amide-amide hydrogen-bonding associations [graph set R2/2(8)]. These chains are cross linked by amide N---H...O~carboxyl~ and piperidinium N-H...O(nitro) associations to give a two-dimensional sheet structure.