1,071 research outputs found
Investigating the effect of a stress-based uniaxial anisotropy on the magnetic behaviour of La<sub>0.7</sub>Sr<sub>0.3</sub>MnO<sub>3</sub> elements
We investigate the interplay between shape anisotropy and a stress-based uniaxial anisotropy on the magnetic domain structure of La<sub>0.7</sub>Sr<sub>0.3</sub>MnO<sub>3</sub> nanoelements as a function of aspect ratio, using micromagnetic simulations. We show that a direct competition between the anisotropies gives rise to high energy multi-domain flux closure configurations, whilst an alignment of the anisotropies can modify the effective element dimensions and act to stabilise a single domain configuration. Our results demonstrate the ability to control the spin state of La<sub>0.7</sub>Sr<sub>0.3</sub>MnO<sub>3</sub> elements in addition to tailoring the domain wall width by controlling the anisotropy of the material, which is key for spintronic applications that require a high spin-polarization and stable magnetic configurations
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Characteristics of successful interventions to reduce turnover and increase retention of early career nurses: a systematic review
Background
nurse shortages have been identified as central to workforce issues in healthcare systems globally and although interventions to increase the nursing workforce have been implemented, nurses leaving their roles, particularly in the first year after qualification, present a significant barrier to building the nurse workforce.
Objective
to evaluate the characteristics of successful interventions to promote retention and reduce turnover of early career nurses.
Design
this is a systematic review
Data sources
Online databases including Academic Search Complete, Medline, Health Policy reference Centre, EMBASE, Psychinfo, CINAHL and the Cochran Library were searched to identify relevant publications in English published between 2001 and April 2018. Studies included evaluated an intervention to increase retention or reduce turnover and used turnover or retention figures as a measure.
Review methods
The review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) guidelines. Studies were quality-assessed using the Joanna Briggs Institute Critical Appraisal tools for Quasi Experimental and Randomised Controlled Trials. Retention/turnover data were used to guide the comparison between studies and appropriate measures of central tendency and dispersion were calculated and presented, based on the normality of the data.
Results
A total of 11, 656 papers were identified, of which 53 were eligible studies. A wide variety of interventions and components within those interventions were identified to improve nurse retention. Promising interventions appear to be either internship/residency programmes or orientation/transition to practice programmes, lasting between 27-52 weeks, with a teaching and preceptor and mentor component.
Conclusions
Methodological issues impacted on the extent to which conclusions could be drawn, even though a large number of studies were identified. Future research should focus on standardising the reporting of interventions and outcome measures used to evaluate these interventions and carrying out further research with rigorous methodology. Clinical practice areas are recommended to assess their current interventions against the identified criteria to guide development of their effectiveness. Evaluations of cost-effectiveness are considered an important next step to maximise return on investment
Simulation and analysis of solenoidal ion sources
We present a detailed analysis and simulation of solenoidal, magnetically confined electron bombardment ion sources, aimed at molecular beam detection. The aim is to achieve high efficiency for singly ionized species while minimizing multiple ionization. Electron space charge plays a major role and we apply combined ray tracing and finite element simulations to determine the properties of a realistic geometry. The factors controlling electron injection and ion extraction are discussed. The results from simulations are benchmarked against experimental measurements on a prototype source
Nanocharacterisation of precipitates in austenite high manganese steels with advanced techniques: HRSTEM and DualEELS mapping
To achieve optimal mechanical properties in high manganese steels, the precipitation of nanoprecipitates of vanadium and niobium carbides is under investigation. It is shown that under controlled heat treatments between 850°C and 950°C following hot deformation, few-nanometre precipitates of either carbide can be produced in test steels with suitable contents of vanadium or niobium. The structure and chemistry of these precipitates are examined in detail with a spatial resolution down to better than 1 nm using a newly commissioned scanning transmission electron microscope. In particular, it is shown that the nucleation of vanadium carbide precipitates often occurs at pre-existing titanium carbide precipitates which formed from titanium impurities in the bulk steel. This work will also highlight the links between the nanocharacterisation and changes in the bulk properties on annealing
Women's experience of male circumcision in Papua New Guinea: a grounded theory study
Background: Understanding how women experience and manage the myriad issues of male circumcision (MC) for themselves, their sexual partners and their sons is essential to understanding broader HIV and sexual health issues in Papua New Guinea (PNG). A great diversity of traditional and contemporary circumcision and foreskin cutting practices exist across the country. Medical MC is currently being investigated as a HIV prevention strategy. Studies have documented mixed responses by women to MC as a HIV prevention method in PNG.
Methods: Between 2012 and 2014, a grounded theory study was conducted using a two-phase approach. Data from a large mixed methods multi-site MC study in 2010/2011 was analysed for themes to inform specific questions for women. Semi-structured interviews and focus group discussions, that incorporated visual methods such as storyboarding, were then conducted with 67 women at two of the initial study sites - a rural oil palm plantation and an urban university site. Data were inductively analysed to identify codes, categories and a grounded theory.
Results: Women have extensive knowledge about MC and foreskin cutting practices, despite cultural norms that mean most women do not participate in decision-making about MC or other penile modifications. Women gain knowledge through personal (sometimes negative) experiences of their partners or children, through cultural traditions and/or through formal training or education. Women who have formal education or training, or who hold formal roles in their communities reported a greater power of choice about their own decision-making, including how MC affects them. Educated women reported more opportunities to influence their partner's decision about MC or other penile modifications, to choose a new partner or arrange MC for their male child/ren.
Conclusions: Increased formal and informal education (such as HIV and sexual health training) results in increased status for women and access to a greater range of choices. The often culturally sanctioned low-status roles for women in PNG can be changed with training and/or formal education, which gives more power and thus more choices. If women have greater power of choice, they are less vulnerable to harmful, unintended consequences that may result from a policy of medical MC
Texture, twinning and metastable "tetragonal" phase in ultrathin films of HfO<sub>2</sub> on a Si substrate
Thin HfO<sub>2</sub> films grown on the lightly oxidised surface of (100) Si wafers have been examined using dark-field transmission electron microscopy and selected area electron diffraction in plan view. The polycrystalline film has a grain size of the order of 100 nm and many of the grains show evidence of twinning on (110) and (001) planes. Diffraction studies showed that the film had a strong [110] out-of-plane texture, and that a tiny volume fraction of a metastable (possibly tetragonal) phase was retained. The reasons for the texture, twinning and the retention of the metastable phase are discussed
Engineering magnetic domain-wall structure in permalloy nanowires
Using Lorentz transmission electron microscopy we investigate the behavior of
domain walls pinned at non-topographic defects in Cr(3 nm)/Permalloy(10
nm)/Cr(5 nm) nanowires of width 500 nm. The pinning sites consist of linear
defects where magnetic properties are modified by a Ga ion probe with diameter
~ 10 nm using a focused ion beam microscope. We study the detailed change of
the modified region (which is on the scale of the focused ion spot) using
electron energy loss spectroscopy and differential phase contrast imaging on an
aberration (Cs) corrected scanning transmission electron microscope. The signal
variation observed indicates that the region modified by the irradiation
corresponds to ~ 40-50 nm despite the ion probe size of only 10 nm. Employing
the Fresnel mode of Lorentz transmission electron microscopy, we show that it
is possible to control the domain wall structure and its depinning strength not
only via the irradiation dose but also the line orientation.Comment: Accepted for publication in Physical Review Applie
High resolution structural characterisation of laser-induced defect clusters inside diamond
Laser writing with ultrashort pulses provides a potential route for the
manufacture of three-dimensional wires, waveguides and defects within diamond.
We present a transmission electron microscopy (TEM) study of the intrinsic
structure of the laser modifications and reveal a complex distribution of
defects. Electron energy loss spectroscopy (EELS) indicates that the majority
of the irradiated region remains as bonded diamond.
Electrically-conductive paths are attributed to the formation of multiple
nano-scale, -bonded graphitic wires and a network of strain-relieving
micro-cracks
Ohmic contacts to n-type germanium with low specific contact resistivity
A low temperature nickel process has been developed that produces Ohmic contacts to n-type germanium with specific contact resistivities down to (2.3 ± 1.8) x10<sup>-7</sup> Ω-cm<sup>2</sup> for anneal temperatures of 340 degC. The low contact resistivity is attributed to the low resistivity NiGe phase which was identified using electron diffraction in a transmission electron microscope. Electrical results indicate that the linear Ohmic behaviour of the contact is attributed to quantum mechanical tunnelling through the Schottky barrier formed between the NiGe alloy and the heavily doped n-Ge.<p></p>
Research workshop to research work: initial steps in establishing health research systems on Malaita, Solomon Islands
<p>Abstract</p> <p>Introduction</p> <p>Atoifi Adventist Hospital is a 90 bed general hospital in East Kwaio, Malaita, Solomon Islands providing services to the population of subsistence villagers of the region. Health professionals at the hospital and attached College of Nursing have considerable human capacity and willingness to undertake health research. However they are constrained by limited research experience, training opportunities, research systems, physical infrastructure and access to resources. This brief commentary describes an 'Introduction to Health Research' workshop delivered at Atoifi Adventist Hospital in September 2009 and efforts to move from 'research workshop' to 'research work'.</p> <p>The Approach</p> <p>Using a participatory-action research approach underpinned by decolonising methodologies, staff from Atoifi Adventist Hospital and James Cook University (Queensland, Australia) collaboratively designed, implemented and evaluated a health research workshop. Basic health research principles and methods were presented using active learning methodologies. Following the workshop, Atoifi Adventist Hospital and Atoifi College of Nursing staff, other professionals and community members reported an increased awareness and understanding of health research. The formation of a local Research Committee, improved ethics review procedures and the identification of local research mentors followed the week long workshop. The workshop has acted as a catalyst for research activity, increasing structural and human resource capacity for local health professionals and community leaders to engage in research.</p> <p>Discussion and Conclusions</p> <p>Participants from a variety of educational backgrounds participated in, and received benefit from, a responsive, culturally and linguistically accessible health research workshop. Improving health research systems at a remote hospital and aligning these with local and national research agendas is establishing a base to strengthen public health research and practice on Malaita, Solomon Islands.</p
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