295 research outputs found
The Effect of Misch Metal Additions on the Structure and Workability of Al-Mg (7-100/.) Alloys
ON the alloying elements used in aluminium alloys,
copper was one of' the earliest employed commercially
and for many years it has been the principal one. Aluminium-copper alloys to which manganese, magnesium
or silicon has been added, belong to the important
group generally known as "Duralumin".
The binary alloys of aluminium with magnesium attra-
cted the interest of investigators as early as 1900.
There have been numerous attempts to utilise for
general purposes alloys containing as Much as 10%
magnesium ; alloys containing up to 30% magnesium
have been used for special purposes
Re-Focusing - Building a Future for Entrepreneurial Education & Learning
The field of entrepreneurship has struggled with fundamental
questions concerning the subject’s nature and purpose. To whom and to
what means are educational and training agendas ultimately directed?
Such questions have become of central importance to policy makers,
practitioners and academics alike. There are suggestions that university
business schools should engage more critically with the lived experiences
of practising entrepreneurs through alternative pedagogical approaches
and methods, seeking to account for and highlighting the social, political
and moral aspects of entrepreneurial practice. In the UK, where funding in
higher education has become increasingly dependent on student fees,
there are renewed pressures to educate students for entrepreneurial
practice as opposed to educating them about the nature and effects of
entrepreneurship. Government and EU policies are calling on business
schools to develop and enhance entrepreneurial growth and skill sets, to
make their education and training programmes more proactive in
providing innovative educational practices which help and facilitate life
experiences and experiential learning. This paper makes the case for
critical frameworks to be applied so that complex social processes
become a source of learning for educators and entrepreneurs and so that
innovative pedagogical approaches can be developed in terms both of
context (curriculum design) and process (delivery methods)
Perceiving ‘capability’ within dynamic capabilities: the role of owner-manager self-efficacy
This article combines two popular, yet separate concepts, dynamic capabilities and self-efficacy. Both are concerned with ability / capability and offer potentially valuable synergies. As such, our in-depth qualitative study based in three micro-enterprises in the United Kingdom (UK), investigated, ‘what role(s) may owner-manager perceived self-efficacy play as a micro-foundation of dynamic capabilities in micro-enterprises?’ Our findings show that perceived self-efficacy can influence dynamic capability enactment in multifaceted ways and even suggest that in some cases, perceived self-efficacy is a crucial component of dynamic capabilities, without which there may be no such capability. These insights help open up the black box of dynamic capabilities by contributing important knowledge to the growing body of research into the micro-foundations of such capabilities. Furthermore, our study illuminates the importance of idiosyncratic micro-foundations of dynamic capabilities in micro-enterprises and expands extant knowledge of the potential effects of self-efficacy in the small business and entrepreneurship domain
Arthroscopic decompression and notchplasty for long-standing anterior cruciate ligament impingement in a patient with multiple epiphyseal dysplasia: a case report
<p>Abstract</p> <p>Introduction</p> <p>Multiple epiphyseal dysplasia is a genetically and clinically heterogeneous osteochondroplasia with symmetrical involvement. It is characterized by joint pain in childhood and early adulthood with early onset of osteoarthritis, mainly affecting the hips.</p> <p>Case presentation</p> <p>We report the case of a 20-year-old man of Asian origin with multiple epiphyseal dysplasia presenting with bilateral knee pain, stiffness and instability found to be caused by bilateral anterior cruciate ligament impingement on abnormal medial femoral condyles. Bilateral staged arthroscopic notchplasty was performed successfully, resulting in subjective relief of pain, and improved range of movement and stability.</p> <p>Conclusion</p> <p>Care should be taken not to exclude a diagnosis of multiple epiphyseal dysplasia when few of the characteristic radiographic features are evident but clinical suspicion is high. This case highlights the scope for subjective symptomatic improvement following a minimum of surgical intervention. We recommend limiting early intervention to managing symptomatic features rather than radiographic abnormalities alone.</p
The impact of antibiotics on growth in children in low and middle income countries: systematic review and meta-analysis of randomised controlled trials
Objectives To determine whether antibiotic treatment leads to improvements in growth in prepubertal children in low and middle income countries, to determine the magnitude of improvements in growth, and to identify moderators of this treatment effect.Design Systematic review and meta-analysis.Data sources Medline, Embase, Scopus, the Cochrane central register of controlled trials, and Web of Science.Study selection Randomised controlled trials conducted in low or middle income countries in which an orally administered antibacterial agent was allocated by randomisation or minimisation and growth was measured as an outcome. Participants aged 1 month to 12 years were included. Control was placebo or non-antimicrobial intervention.Results Data were pooled from 10 randomised controlled trials representing 4316 children, across a variety of antibiotics, indications for treatment, treatment regimens, and countries. in random effects models, antibiotic use increased height by 0.04 cm/month (95% confidence interval 0.00 to 0.07) and weight by 23.8 g/month (95% confidence interval 4.3 to 43.3). After adjusting for age, effects on height were larger in younger populations and effects on weight were larger in African studies compared with other regions.Conclusion Antibiotics have a growth promoting effect in prepubertal children in low and middle income countries. This effect was more pronounced for ponderal than for linear growth. the antibiotic growth promoting effect may be mediated by treatment of clinical or subclinical infections or possibly by modulation of the intestinal microbiota. Better definition of the mechanisms underlying this effect will be important to inform optimal and safe approaches to achieving healthy growth in vulnerable populations.Vanier Canada Graduate ScholarshipMcGill Univ, Dept Epidemiol Biostat & Occupat Hlth, Montreal, PQ, CanadaZvitambo Inst Maternal Child Hlth Res, Harare, ZimbabweQueen Mary Univ London, Blizard Inst, Ctr Paediat, London, EnglandMRC, Clin Trials Unit, London, EnglandJohns Hopkins Bloomberg Sch Publ Hlth, Dept Int Hlth, Baltimore, MD USACornell Univ, Div Nutr Sci, Program Int Nutr, Ithaca, NY 14853 USAWashington Univ, Sch Med, Dept Pediat, St Louis, MO 63110 USAUniv Malawi, Blantyre, MalawiUniv Cambridge, Dept Archaeol & Anthropol, Div Biol Anthropol, Cambridge CB2 1TN, EnglandUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo, BrazilUniv British Columbia, Sch Populat & Publ Hlth, Vancouver, BC V6T 1Z3, CanadaUniversidade Federal de São Paulo, Escola Paulista Med, São Paulo, BrazilWeb of Scienc
Integration of HIV Care into Community Management of Acute Childhood Malnutrition Permits Good Outcomes: Retrospective Analysis of Three Years of a Programme in Lusaka
Background While HIV has had a major impact on health care in southern Africa, there are few data on its impact on acute malnutrition in children in the community. We report an analysis of outcomes in a large programme of community management of acute malnutrition in the south of Lusaka. Programme activities and analysis Over 3 years, 68,707 assessments for undernutrition were conducted house-to-house, and children with severe acute malnutrition (SAM) or moderate acute malnutrition (MAM) were enrolled into either Outpatient Therapeutic Programme (OTP) or Supplementary Feeding Programme (SFP) respectively. Case records were analysed using tabulation and unconditional logistic regression. Findings 1,859 children (889 boys, 970 girls; median age 16 months) with MAM (n=664) or SAM (n=1,195) were identified. Of 1,796 children whose parents consented to testing, 185 (10.3%) were HIV positive. Altogether 1,163 (62.6%) were discharged as recovered from acute malnutrition. Case fatality while in the programme was 4.2% in children with SAM and 0.5% in those with MAM (RR of SAM 10.9; 95%CI 3.4,34.8; P<0.0001), and higher in children with HIV infection (RR 5.2, 95%CI 2.9, 9.0; P<0.0001). In multivariate analysis, HIV (OR 5.2; 95%CI 2.6, 10.1; P<0.0001), MUAC <11.5cm (OR 4.1; 95%CI 2.2, 7.4; P<0.0001) and the first year of the programme (OR 1.9; 95%CI 1.0, 3.4; P=0.04) all increased mortality. Children with HIV infection who were able to initiate antiretroviral therapy had lower mortality (RR 0.23; 95%CI 0.10, 0.57; P=0.0008). Interpretation Our programme suggests that a comprehensive community malnutrition programme, incorporating HIV care, can achieve low mortality even in a population heavily affected by HIV
In Situ Observations during Chemical Vapor Deposition of Hexagonal Boron Nitride on Polycrystalline Copper.
Using a combination of complementary in situ X-ray photoelectron spectroscopy and X-ray diffraction, we study the fundamental mechanisms underlying the chemical vapor deposition (CVD) of hexagonal boron nitride (h-BN) on polycrystalline Cu. The nucleation and growth of h-BN layers is found to occur isothermally, i.e., at constant elevated temperature, on the Cu surface during exposure to borazine. A Cu lattice expansion during borazine exposure and B precipitation from Cu upon cooling highlight that B is incorporated into the Cu bulk, i.e., that growth is not just surface-mediated. On this basis we suggest that B is taken up in the Cu catalyst while N is not (by relative amounts), indicating element-specific feeding mechanisms including the bulk of the catalyst. We further show that oxygen intercalation readily occurs under as-grown h-BN during ambient air exposure, as is common in further processing, and that this negatively affects the stability of h-BN on the catalyst. For extended air exposure Cu oxidation is observed, and upon re-heating in vacuum an oxygen-mediated disintegration of the h-BN film via volatile boron oxides occurs. Importantly, this disintegration is catalyst mediated, i.e., occurs at the catalyst/h-BN interface and depends on the level of oxygen fed to this interface. In turn, however, deliberate feeding of oxygen during h-BN deposition can positively affect control over film morphology. We discuss the implications of these observations in the context of corrosion protection and relate them to challenges in process integration and heterostructure CVD.P.R.K. acknowledges funding from the Cambridge Commonwealth Trust and the Lindemann
Trust Fellowship. R.S.W. acknowledges a research fellowship from St. John’s College,
Cambridge. S.H. acknowledges funding from ERC grant InsituNANO (no. 279342), EPSRC
under grant GRAPHTED (project reference EP/K016636/1), Grant EP/H047565/1 and EU FP7
Work Programme under grant GRAFOL (project reference 285275). The European Synchrotron
Radiation Facility (ESRF) is acknowledged for provision of synchrotron radiation and assistance
in using beamline BM20/ROBL. We acknowledge Helmholtz-Zentrum-Berlin Electron storage
ring BESSY II for synchrotron radiation at the ISISS beamline and continuous support of our
experiments.This is the final version. It was first published by ACS at http://pubs.acs.org/doi/abs/10.1021/cm502603
Innovation development – an action learning programme for medical scientists and engineers
© 2014, © 2014 Taylor & Francis. There is increasing evidence that action learning is valuable in a higher education setting. This paper goes on to report a personal development programme, based on principles of critical action learning, where the aim is to equip early-career scientists and engineers working in a university setting with the knowledge, skills and confidence to approach the management of innovation. After learning about action learning and critical reflection, the participants, all postdoctorate researchers, completed innovation projects at work, meeting in action learning sets as they proceed. We explain a method of critical thinking before reporting results from an evaluation study based on interviews and focus groups. We consider examples of projects undertaken before considering challenges for students with this approach to learning. Challenges included scepticism about the usefulness of management literature, difficulties in finding ‘problems’ within the constraints of postdoctoral work, and the discomfort and intensiveness of action learning. However, through adaptation by the tutors with students, some significant results were achieved
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