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Life-time and current suicide-ideation in Australian secondary school students : socio-demographic, health and psychological predictors
No full textConclusions: Adolescent girls and adolescents with poor social and family functioning and those who engage in substance use are at risk of suicidal ideation (a known precursor of suicide attempts). School counsellors and teachers need to be aware of the risks.
Continuing differences between health professions' attitudes : the saga of accomplishing systems-wide interprofessionalism
No full textConclusions. Although overall attitudes towards IPC were favourable, only a third of participants reported that project goals had been achieved indicating the difficulties of implementing systems change. The response profiles of the professions differed. As in the previous research, doctors were least likely to hold favourable attitudes towards or endorse benefits from social or structural interventions in health care.
Primary motor cortex function in complex regional pain syndrome: A systematic review and meta-analysis
No full textDysfunction in the central nervous systemis thought to underlie themovement disorders that commonly occur in complex regional pain syndrome (CRPS), with much of the literature focusing on reorganization of the primary motor cortex (M1). Presumed changes in the M1 representation of the CRPS-affected body part have contributed to new CRPS treatments, which are increasingly being integrated in the clinic. We systematically investigated the evidence for altered M1 function in CRPS. We adhered to rigorous systematic review procedure in our search strategy, risk-of-bias appraisal, and data extraction. Eighteen studies comprising 14 unique data sets were included. The included studies used several neuroimaging techniques, whose outcomeswe grouped intoM1 cortical excitability, spatial representation, reactivity, and glucose metabolism, and conducted meta-analyses where possible. Risk of bias across studies was high, mainly due tomissing data and unblinded assessment of outcomes. No definitive conclusions can be drawn regarding M1 spatial representation, reactivity, or glucose metabolism in CRPS. There is limited evidence for bilateralM1 disinhibition in CRPS of the upper limb.
Controlled covalent surface immobilisation of proteins and peptides using plasma methods
No full textCoated layers of biologically active molecules on synthetic biomaterials and biomedical devices can promote a variety of desirable biological reactions by the host body or the biological medium, such as cell and tissue attachment or deterring bacterial biofilm formation. Such coated layers should be immobilised covalently in order to avoid competitive displacement phenomena, and the use of surface-activating plasmas or plasma polymer interlayers with suitable chemical surface groups has proved to be very convenient means of grafting bioactive molecules onto solid materials surfaces. We review selected work on the covalent immobilisation of proteins and peptides onto solid biomaterial surfaces and describe efforts towards plasma methods that allow biomolecules to be covalently captured in a single step. After reviewing a number of approaches, we discuss in more detail the use of plasma polymer interlayers that possess aldehyde or epoxide surface groups; these groups react readily with amine groups on proteins and peptides without undesirable side reactions, and avoid other issues such as crosslinking. We also emphasise the importance of detailed surface analysis to verify that covalent grafting has indeed taken place, and to assess the surface density of grafted molecules. With suitably chosen peptides or proteins, such covalently grafted layers can support the surface attachment of delicate cells, or combat bacterial biofilm formation.
Determination of phosphorus fertilizer soil reactions by Raman and synchrotron infrared microspectroscopy
No full textThe reaction mechanisms of phosphate-bearing mineral phases from sewage sludge ash-based fertilizers in soil were determined by Raman and synchrotron infrared microspectroscopy. Different reaction mechanisms in wet soil were found for calcium and magnesium (pyro-) phosphates. Calcium orthophosphates were converted over time to hydroxyapatite. Conversely, different magnesium phosphates were transformed to trimagnesium phosphate. Since the magnesium phosphates are unable to form an apatite structure, the plant-available phosphorus remains in the soil, leading to better growth results observed in agricultural pot experiments. The pyrophosphates also reacted very differently. Calcium pyrophosphate is unreactive in soil. In contrast, magnesium pyrophosphate quickly formed plant-available dimagnesium phosphate.
Domain-Specific Consumer Involvement in the U.S. Wine Market
No full textAn 18-item multidimensional scale was developed to measure wine consumer involvement level impact on behavior and consumption dynamics. Data were collected at wine tasting events in Portland, Oregon, U.S., yielding a final sample size of 101 respondents. Male wine consumers do not display a higher level of involvement with wine as a product than females, and neither do consumers 45 years and older in comparison with younger consumers. Consumers with high education and income levels do not use these as a basis of their involvement level with wine. Price is not more frequently used by low involvement wine drinkers in the wine purchasing decision.
Impact of nanoscale surface heterogeneity on precursor film growth and macroscopic spreading of [Rmim][NTf2] ionic liquids on mica
No full textThe connection between the interfacial properties of ionic liquids and their wetting behavior has been studied very little to date and not at all on heterogeneous surfaces. Therefore, we have investigated the static and dynamic wetting for a family of ionic liquids, 1-alkyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide, [Rmim][NTf2], on mica, where R represents an ethyl, butyl, or hexyl alkyl chain on the imidazolium ring. Spreading is impacted greatly by a precursor film that forms on both homogeneous and heterogeneous mica surfaces. Macroscopically, the initial viscous spreading of the ionic liquid droplet on bare mica occurs within seconds but is then followed by a very slow relaxation that can be closely correlated with the typical time-scales of the precursor film growth. The contact angle for [emim][NTf2] and [bmim][NTf2] relaxes from about 40° to 23° over 30 and 90 min, respectively. For [hmim][NTf2], the process takes approximately 24 h and approaches complete wetting. The thickness of the precursor films for [emim][NTf2], [bmim][NTf2], and [hmim][NTf2] were 0.53, 0.65, and 1.0 nm, respectively, according to atomic force microscopy (AFM). These values are consistent with a monolayer of ionic liquid cations on mica, rather than ion pairs. A monolayer of octadecylphosphonic acid (OPA) on mica prevents both the formation of a precursor film and the relaxation of the contact angle. However, only a partial surface coverage of 60% OPA is required to have the same effect. Quenching of precursor film formation (and associated contact angle relaxation) is due to an increasingly connected network of OPA regions that closes the nanoscale paths of bare mica on which the precursor film can develop via surface diffusion.
Rolling, penetration and evaporation of alcohol-water drops on coarse and fine hydrophobic powders
No full textAgglomeration of hydrophobic powders using aqueous solutions is an important technology. The outcome is linked to the particle wettability, but the mechanisms are not well-understood. We present a fundamental study of the early stages of agglomeration. Drops of alcohol–water mixtures were deposited onto three hydrophobic powders: hydrophobised glass beads (spherical, 90–106 μm), coal dust (angular shape, 90–106 μm) and molybdenite powder (angular shape, 1–20 μm). Their wettability was manipulated through the surface tension of the liquid, which was varied by the alcohol–water ratio. On coarse powders (glass beads and coal dust) the droplet either penetrates into the porous bed (at low surface tensions and contact angles), or sits on top and evaporates (at higher surface tensions and contact angles). Particles spontaneously coat drops of intermediate surface tension. The coating slows evaporation and remains as a dry agglomerate after evaporation. Drops that do not penetrate into the fine powder beds (molybdenite) spontaneously roll away, even when deposited carefully. The reason is that the powder surface behaves like a superhydrophobic one. Rolling drops collect hydrophobic particles along their path. After rolling, the partially coated drop evaporates in the same way as on coarser powders.
Increasing physical activity in young primary school children - it's child's play: A cluster randomised controlled trial
No full textConclusions: Capturing children's intrinsic motivations to play while simultaneously helping adults reconsider views of free play as risky provided increases in physical activity during break times. Using accelerometry as the sole measure of physical activity may underestimate the effect.