401 research outputs found

    New initiators for the polymerisation of bio-based monomers

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    Cultivating care: Nurturing Nurses for a New Tomorrow

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    In large academic institutions, students often feel very lost, confused, lonely, and anxious or even a fraud at being there. At Edith Cowan University in Western Australia, researchers identified a gap in provision for Nursing Students which addresses these concerns. This study used a qualitative case study utilising rich narrative and aesthetic expression to explore and describe the experiences of both student mentees and academic mentors over the trajectory of the student’s Bachelor Degree programme. Findings emerging show students both want and need academic mentorship but the form upon which that takes is highly individual and changeable as the individuals professional competence and confidence increases; and as a positive and mutually accountable relationship is formed between the parties. While there is overwhelming empirical evidence to support mentorship for students in academic institutions and mentorship for newly Registered Nurses, a paucity of literature exploring academic mentorship of student nurses exists. This research aims to contribute to an emerging yet vital body of knowledge surrounding the notions of support and nurturing of health professionals of the future. A philosophical model proposed by the researchers has been identified as the foundation for this research and will also be explored within this paper

    Salan Group 13 complexes – structural study and lactide polymerisation

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    Herein the preparation and characterisation of a series of group 13 salan complexes, with a bipyrrolidine or N,N’-ethylenediamine backbone are disclosed. For the bipyrrolidine derived-salan ligand 1H2, the Al(III) and Ga(III) complexes are pseudo trigonal bipyramidal in the solid-state, whereas the In(III) complexes are best described as square based pyramidal structures. However, for the ethylenediamine derived-salan ligand 2H2, all complexes are effectively square based pyramidal in their structure. The complexes’ solution behaviour is also investigated by NMR spectroscopic methods and it is observed that the solid-state structure is maintained in solution. The complexes have all been trialled for the ring opening polymerisation of rac-lactide. With In(1)Cl controlled polymerisation and narrow molecular weight distributions (1.01 – 1.08) are observed with heterotactic polylactide being prepared. Under the conditions tested the Ga(III) and Al(III) complexes were shown to be inactive

    Oil-in-oil droplet stability dependence on dimensions of 2D Pickering particles of controlled size

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    Non-aqueous emulsions are employed for a host of important applications; however, their long-term stability often limits their use. 2D particles have been reported to provide greater emulsion stability compared to surfactants and isotropic particles as a result of their greater interfacial area interaction. Here, control over the particle size resulted in control over the droplet diameter and increased stability. Non-aqueous emulsions are widely employed; therefore, characterising the effect of the dimensions of 2D particles on their stability is key to making oil-in-oil (o/o) emulsions with enhanced properties. This study investigates the self-assembly of uniform 2D particles of a controlled size, and their application as Pickering particles in o/o emulsions. The correlation between 2D particle dimensions and emulsion characteristics was investigated, a comparison that has not been reported for o/o emulsions prior to this study

    Aquatic insects dealing with dehydration: do desiccation resistance traits differ in species with contrasting habitat preferences?

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    Background Desiccation resistance shapes the distribution of terrestrial insects at multiple spatial scales. However, responses to drying stress have been poorly studied in aquatic groups, despite their potential role in constraining their distribution and diversification, particularly in arid and semi-arid regions. Methods We examined desiccation resistance in adults of four congeneric water beetle species (Enochrus, family Hydrophilidae) with contrasting habitat specificity (lentic vs. lotic systems and different salinity optima from fresh- to hypersaline waters). We measured survival, recovery capacity and key traits related to desiccation resistance (fresh mass, % water content, % cuticle content and water loss rate) under controlled exposure to desiccation, and explored their variability within and between species. Results Meso- and hypersaline species were more resistant to desiccation than freshwater and hyposaline ones, showing significantly lower water loss rates and higher water content. No clear patterns in desiccation resistance traits were observed between lotic and lentic species. Intraspecifically, water loss rate was positively related to specimens’ initial % water content, but not to fresh mass or % cuticle content, suggesting that the dynamic mechanism controlling water loss is mainly regulated by the amount of body water available. Discussion Our results support previous hypotheses suggesting that the evolution of desiccation resistance is associated with the colonization of saline habitats by aquatic beetles. The interespecific patterns observed in Enochrus also suggest that freshwater species may be more vulnerable than saline ones to drought intensification expected under climate change in semi-arid regions such as the Mediterranean Basin

    Ring-opening polymerisation of alkyl-substituted ε-caprolactones:kinetic effects of substitution position†

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    Ring-opening polymerisation (ROP) of lactones has been proven as a powerful technique to generate polyesters with high levels of control over molar mass and polymer dispersity. However, the introduction of functional groups on the monomer ring structure can dramatically influence the ability of a monomer to undergo ROP. Therefore, understanding the structure–reactivity relationship of functional monomers is essential to gain access to materials with chemical functionality via direct polymerisation. Herein, we report how structural modifications of alkyl-substituted ε-caprolactones affected their reactivity towards the ring-opening of the functional monomer. We observed that the reactivity was strongly influenced by the substituent position, wherein the δ-substituted monomer exhibited the fastest polymerisation kinetics. In contrast, a substituent placement in the ε-position significantly reduced polymerisation time compared to other substituent positions. Moreover, the thermal properties of the resultant functional ε-polycaprolactones were investigated and showed no significant change in the thermal transitions. This demonstrates that functional caprolactone monomers with sterically demanding functional groups can still undergo direct ring-opening polymerisation and that careful positioning of these functional groups enables control of the rate of polymerisation, a crucial parameter to be considered for the design of new prospective functional monomers and their industrial applications

    Copolymerization of Cyclic Phosphonate and Lactide: Synthetic Strategies toward Control of Amphiphilic Microstructure

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    Controlling the microstructure of polymers through chemical reactivity is key to control the material properties of synthetic polymers. Herein we investigate the ring-opening copolymerization of a mixture of lactide and 2-ethyl-2-oxo-1,3,2-dioxaphospholane, promoted by an aluminum pyrrolidine monophenolate complex or 1,8-diazabicyclo[5.4.0]­undec-7-ene (DBU). This monomer mixture provides fast access to amphiphilic copolymers. The reaction conditions control the copolymer microstructure, which has been determined via a combination of <sup>1</sup>H and <sup>31</sup>P NMR spectroscopy. The choice of initiator has a profound impact: both initiators produce tapered block copolymers but with reverse monomer selectivity. While the aluminum initiator favors the cyclic phosphonate monomer, DBU favors lactide polymerization. Moreover, a sequential control of temperature facilitates the preparation of block copolymers in one pot. Thermal properties measured by TGA and DSC correlate to copolymer architectures. This methodology is the first report of copolymerization between cyclic phosphonates and lactide and opens the possibility to tune the thermal properties, solubility, and degradation rates of the resulting materials

    Would you recommend nursing to men as a career?

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    Objective : The principle objective of this study was to establish a profile and perception of men in nursing in Western Australia. This paper will discuss one sub-objective which sort to explore responses to the question: “Would you recommend a nursing as a career to males that you know?” Design: Main study was a quantitative, descriptive survey design, however the question under review was significantly qualitative in nature and analysed as such. Setting : The study took place across Western Australian public and private sector health care facilities, nurse education institutions and non- government providers across rural, remote and metropolitan locations. Main outcome measures: Data was collected through responses to one question (within a larger survey) that related to recommending nursing as a career to males. An online survey instrument was used. Results: 70.5 %( n= 377) said they would recommend nursing to males. Of the respondents that selected “yes” 19.6% were male and 80.4 % were female. Of the 29.5 %( n= 158) respondents that selected “no” 24.7% were male and 75.3% female. Qualitative data reported supports the perceptions in the current workforce. Conclusion : Whilst the majority of respondents in the study would recommend a career in nursing to men, a quarter of respondents felt that a career in nursing was not suited to men. Reasons identified included; poor pay, a difficult job, men’s values were incompatible with care, or that they were using nursing as a spring board to other careers. Identifying the perceptions of men in nursing and if current nurses would promote nursing to males they knew assists in the potential recruitment of a much needed future workforce

    The comparative osmoregulatory ability of two water beetle genera whose species span the fresh-hypersaline gradient in inland waters (Coleoptera: Dytiscidae, Hydrophilidae).

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    A better knowledge of the physiological basis of salinity tolerance is essential to understanding the ecology and evolutionary history of organisms that have colonized inland saline waters. Coleoptera are amongst the most diverse macroinvertebrates in inland waters, including saline habitats; however, the osmoregulatory strategies they employ to deal with osmotic stress remain unexplored. Survival and haemolymph osmotic concentration at different salinities were examined in adults of eight aquatic beetle species which inhabit different parts of the fresh-hypersaline gradient. Studied species belong to two unrelated genera which have invaded saline waters independently from freshwater ancestors; Nebrioporus (Dytiscidae) and Enochrus (Hydrophilidae). Their osmoregulatory strategy (osmoconformity or osmoregulation) was identified and osmotic capacity (the osmotic gradient between the animal's haemolymph and the external medium) was compared between species pairs co-habiting similar salinities in nature. We show that osmoregulatory capacity, rather than osmoconformity, has evolved independently in these different lineages. All species hyperegulated their haemolymph osmotic concentration in diluted waters; those living in fresh or low-salinity waters were unable to hyporegulate and survive in hyperosmotic media (> 340 mosmol kg(-1)). In contrast, the species which inhabit the hypo-hypersaline habitats were effective hyporegulators, maintaining their haemolymph osmolality within narrow limits (ca. 300 mosmol kg(-1)) across a wide range of external concentrations. The hypersaline species N. ceresyi and E. jesusarribasi tolerated conductivities up to 140 and 180 mS cm(-1), respectively, and maintained osmotic gradients over 3500 mosmol kg(-1), comparable to those of the most effective insect osmoregulators known to date. Syntopic species of both genera showed similar osmotic capacities and in general, osmotic responses correlated well with upper salinity levels occupied by individual species in nature. Therefore, osmoregulatory capacity may mediate habitat segregation amongst congeners across the salinity gradient

    The male of the species: a profile of men in nursing

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    Aim: To establish a profile of men in nursing in Western Australia and explore the perception of men in nursing from the perspective of male and female nurses. Background: A project team, including some of the current authors, produced a YouTube video and DVD about men in nursing which led to further inquiry on this topic. Design: The study employed a non-experimental, comparative, descriptive research design focused on a quantitative methodology, using an online survey in early 2014. Method: A convenience sample incorporated registered and enrolled nurses and midwives in Western Australia. Findings: The range of data included demographic information and the respondents’ perceptions of men in nursing were collected. Findings indicated that the main reasons for choosing a career in nursing or midwifery were similar for both genders. Common mis-perceptions of men in nursing included: most male nurses are gay; men are not suited to nursing and men are less caring and compassionate than women. Suggestions to promote nursing to men included: nurses are highly skilled professionals; there is the potential to make a difference for patients; nursing offers stable employment, professional diversity and opportunities for team work. There is a diminished awareness of opportunities for men in nursing and negative stereotypes related to men in nursing persist. Conclusion: The study produced recommendations which included: using the right message to target the recruitment for men and promoting a more realistic understanding of the profile and perception of men in nursing
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