7,490 research outputs found
Designing and managing multiple pipelines
There is now a growing recognition that supply chains should be designed from
âthe customer backwardsâ rather than from âthe company outwardsâ. If such a view
is accepted then the implication is that since the organisation will likely be
serving multiple markets or segments there will be the need to design and manage
multiple âpipelinesâ to serve those different customers. To assist decision
makers in their choice of appropriate supply chain design a framework is
proposed based upon multiple criteria. A case study is presented which
highlights the benefits of selecting, engineering and operating multiple
pipelines tailored to the needs of th
Eileen Mackenzie. The Findlater Sisters: Literature & Friendship. London. John Murray. 1964. xiii, 150 pp. 21/-.
Elgin W. Mellown. Bibliography of the Writings of Edwin Muir. University, Ala. University of Alabama Press. 1964. 139 pp. $5.95. Rev. ed. London. Nicholas Vane, 1966. 144 pp. 50 shillings.
Eosinophile Leucocyte: its occurrence and significance with special reference to asthma
I. There are four main groups of conditions in which eosinophilia is of frequent occurrence:-(a) Convalescence from infectious fevers, and in the course of scarlet fever.(h) Skin diseases.(c) Asthma.(d) Parasitic infestations.II. The eosinophilia is of low grade in convaÂlescence and in most skin diseases,except dermatitis herpetiformis and pemphigus.III. A low grade eosinophilia is present in 50 per cent of asthmatic patients.IV. High grade eosinophilia is specially associated with infestations of Bilharzia, Pilaria, Trichina and Ankylostoma; a low grade eosinophilia may occur with any parasitic infestation
Basic Derivatives of Fluorene and Anthracene, and Isomerisation Reactions with Hydrogen Fluoride
Part I. Attempts to prepare the basic esters beta-diethyl-aznino ethyl 1,2,3,4,10,11-hexahydrof luorene-9-carboxylate and beta-diethylaminoethyl 1,2,3,4,9,10,11,12-octahydro-anthracene-9-carboxylate for testing as antispasmodic drugs have been made. These compounds have certain structural features which, in similar compounds, have been found to enhance the antispasmodic properties of these compounds. The reduction of fluorene-9-carboxylic acid has been studied with limited success. Hexahydrofluorene-9-carboxylic acid, an intermediate required in the synthesis of the former ester, has been obtained but only in poor yield. A further acid of unknown structure and several neutral by-products have also been isolated. Other synthetic methods failed due to the reluctance of hexahydro-fluorenone to form a cyanhydrin and the ease with which 9-halogene-hexahydrofluorenes decomposed. trans- as-hexahydroanthrone did not form a cyanhydrin so that trans- as- octahydroanthracene-9-carboxylio acid, an intermediate in the synthesis of the latter ester, was not obtained. The basic ethers, beta-diethylaminoethyl fluorenyl-9-ether. beta-diethylsaminoethyl hexahydrofluorenyl-9-ether and beta-diethylaminoethyl trans-as-octahydroanthranyl-9-ether, also required for testing as antispasmodic drugs, were obtained by condensation of the sodio-derivatives of the alcohols 9-fluorenol, hexahydrofluoren-9-ol and 9-hydroxy-traus-as-octahydroanthracene, respectively, with beta-diethylaminoethyl chloride. Summary, Part II. A study of a new type of isomerisation reaction (68, 69) using hydrogen fluoride as catalyst has been extended to durene (1,2,4,5-tetramethylbenzene) and penta-methylbenzene derivatives. It has been confirmed that migration of methyl groups in this reaction occurs only when accompanied by cyclisation. Durene, durylcarboxylic acid and durylacetic acid were unaffected by treatment with hydrogen fluoride at room temperature . Under similar conditions beta-durylpropionic acid was partially converted to a mixture of 4,5,7-trimethyl-indan-l-one and 4,5,6,7-tetramethylindan-l-one. The latter ketone was also obtained from beta-pentamethylphenylpropionio acid under identical conditions. Similarly 1-durylbutyric acid yielded 5,6,7,8-tetramethyl-1,2,3,4-tetrahydroanphthalen-l-one. l-pentamethylphenylbutyric acid was recovered un- changed on similar treatment. Similarities between this type of reaction and previously described isomerisation reactions have been noted though migration in this new type of isomerisation reaction appears to be much more limited in extent. A possible mechanism for the new type of reaction, based on these similarities, has been evolved. A partial isomerisation in the durene nucleus under the influence of aluminium chloride under mild conditions has been noted and correlated to a similar isomerisation in the s-octahydroanthracene nucleus and to the Jacobsen reaction
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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
An asymmetric synthesis of chiral 4,4-disubstituted cyclohexenones in high enantiomeric purity
Synthesis, structure and pyrolysis of stabilised phosphonium ylides containing saturated oxygen heterocycles
yesA range of twelve stabilised phosphonium ylides containing tetrahydrofuran, tetrahydropyran or 2,2-
dimethyl-1,3-dioxolane rings have been prepared and fully characterised, including one X-ray structure
determination of each type. The X-ray structures confirm the PvC and CvO functions to be syn and all
the compounds undergo thermal extrusion of Ph3PO to give the corresponding alkynes. In some cases
there is also competing loss of Ph3P to give different carbene-derived products and evidence has been
obtained for the generation of 2-phenyloxete in this way. Raising the pyrolysis temperature leads in
several cases to new secondary reactions of the alkyne products involving a sequence of alkyne to vinylidene
isomerisation, intramolecular CH insertion, and retro Diels Alder reaction
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