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Global Competition, Institutions, And The Diffusion Of Organizational Practices: The International Spread Of Iso 9000 Quality Certificates
We use panel data on ISO 9000 quality certification in 85 countries between 1993 and 1998 to better understand, the cross-national diffusion of an organizational practice. Following neoinstitutional theory, we focus on the coercive, normative, and mimetic effects that result from the exposure of firms in a given country to a powerful source of critical resources, a common pool of relevant technical knowledge, and the experiences of firms located in other countries. We use social network theory to develop a systematic conceptual understanding of how firms located in different countries influence each other's rates of adoption as a result of cohesive and equivalent network relationships. Regression results provide support for our predictions that states and foreign multinationals are the key actors responsible for coercive isomorphism, cohesive trade relationships between countries generate coercive and normative effects, and role-equivalent trade relationships result in learning-based and competitive imitation.Business Administratio
The Origin and Significance of Reverse Zoning in Melilite from Allende Type B Inclusions
In many Type B Allende inclusions, melilite is reversely-zoned over restricted portions of each crystal. Textural relationships and the results of dynamic crystallization experiments suggest that the reverselyzoned intervals in these Type melilites result from the co-precipitation of melilite with clinopyroxene from a melt, prior to the onset of anorthite precipitation. When clinopyroxene begins to precipitate, the Al/Mg ratio of the melt rises, causing the crystallizing melilite to become more gehlenitic, an effect which is negated by crystallization of anorthite. Because the equilibrium crystallization sequence in these liquids is anorthite before pyroxene, melilite reverse zoning can occur only when anorthite nucleation is suppressed relative to pyroxene. This has been achieved in our experiments at cooling rates as low as 0.5°C/hour. Our experiments further indicate, however, that reverse zoning does not form at cooling rates ≥50°C/hour , probably because the clinopyroxene becomes too Al-rich to drive up the Al/Mg ratio of the liquid. Type inclusions with reversely-zoned melilites must have cooled at rates greater than those at which anorthite begins to crystallize before clinopyroxene but <50°C/hour. Such rates are far too slow for the Type droplets to have cooled by radiation into a nebular gas but are much faster than the cooling rate of the solar nebula itself. One possibility is that Type B's formed in local hot regions within the nebula, where their cooling rate was equal to that of their surrounding gas. Other possibilities are that their cooling rates reflect their movement along nebular temperature gradients or the influence of a heat source. The sun or viscous drag on inclusions as they moved through the nebular gas are potential candidates for such heat sources
Interaction of Supernova Ejecta with Nearby Protoplanetary Disks
The early Solar System contained short-lived radionuclides such as 60Fe (t1/2
= 1.5 Myr) whose most likely source was a nearby supernova. Previous models of
Solar System formation considered a supernova shock that triggered the collapse
of the Sun's nascent molecular cloud. We advocate an alternative hypothesis,
that the Solar System's protoplanetary disk had already formed when a very
close (< 1 pc) supernova injected radioactive material directly into the disk.
We conduct the first numerical simulations designed to answer two questions
related to this hypothesis: will the disk be destroyed by such a close
supernova; and will any of the ejecta be mixed into the disk? Our simulations
demonstrate that the disk does not absorb enough momentum from the shock to
escape the protostar to which it is bound. Only low amounts (< 1%) of mass loss
occur, due to stripping by Kelvin-Helmholtz instabilities across the top of the
disk, which also mix into the disk about 1% of the intercepted ejecta. These
low efficiencies of destruction and injectation are due to the fact that the
high disk pressures prevent the ejecta from penetrating far into the disk
before stalling. Injection of gas-phase ejecta is too inefficient to be
consistent with the abundances of radionuclides inferred from meteorites. On
the other hand, the radionuclides found in meteorites would have condensed into
dust grains in the supernova ejecta, and we argue that such grains will be
injected directly into the disk with nearly 100% efficiency. The meteoritic
abundances of the short-lived radionuclides such as 60Fe therefore are
consistent with injection of grains condensed from the ejecta of a nearby (< 1
pc) supernova, into an already-formed protoplanetary disk.Comment: 57 pages, 16 figure
Effectiveness and reach of a directed-population approach to improving dental health and reducing inequalities: a cross sectional study
Background
Childsmile School adopts a directed-population approach to target fluoride varnish applications to 20% of the primary one (P1) population in priority schools selected on the basis of the proportion of enrolled children considered to be at increased-risk of developing dental caries. The study sought to compare the effectiveness of four different methods for identifying individuals most in need when a directed-population approach is taken. <p></p>
Methods
The 2008 Basic National Dental Inspection Programme (BNDIP) cross-sectional P1 Scottish epidemiological survey dataset was used to model four methods and test three definitions of increased-risk. Effectiveness was determined by the positive predictive value (PPV) and explored in relation to 1-sensitivity and 1-specificity. <p></p>
Results
Complete data was available on 43470 children (87% of the survey). At the Scotland level, at least half (50%) of the children targeted were at increased-risk irrespective of the method used to target or the definition of increased-risk. There was no one method across all definitions of <i>increased-risk</i> that maximised PPV. Instead, PPV was highest when the targeting method complimented the definition of <i>increased-risk</i>. There was a higher percentage of children at <i>increased-risk</i> who were not targeted (1-sensitivity) when caries experience (rather than deprivation) was used to define <i>increased-risk</i>, irrespective of the method used for targeting. Over all three definitions of <i>increased-risk</i>, there was no one method that minimised (1-sensitivity) although this was lowest when the method and definition of <i>increased-risk</i> were complimentary. The false positive rate (1-specificity) for all methods and all definitions of <i>increased-risk</i> was consistently low (<20%), again being lowest when the method and definition of <i>increased-risk</i> were complimentary. <p></p>
Conclusion
Developing a method to reach all (or even the vast majority) of individuals at <i>increased-risk</i> defined by either caries experience or deprivation is difficult using a directed-population approach at a group level. There is a need for a wider debate between politicians and public health experts to decide how best to reach those most at need of intervention to improve health and reduce inequalities. <p></p>
A protocol for a systematic review of clinical guidelines and published systematic reviews on the early detection of oral cancer
Background: The predicted increase in incidence of oral cavity cancer (OCC) coupled with high mortality and poor prognosis – particularly when diagnosed at a late/advanced stage – highlights the need for prevention and early detection/screening to reverse these trends. Dental healthcare professionals in primary care settings have a pivotal role in this effort.
Aim: The aim of this protocol is to detail the process for assessing the evidence for the best practice and methods of early detection/screening for OCC in primary care dental settings by undertaking a systematic review of global clinical guidelines and published systematic reviews.
Method: Searches for clinical guidelines and systematic reviews will be conducted in the following databases: Cochrane library, Medical Literature Analysis and Retrieval System Online (Ovid), Excerpta Medical dataBASE, PubMed, Turning Research into Practice, SCOPUS and Web of Science Core Collection. Our search will extend to include Google Scholar and international professional organizations/associations websites. In addition, we will handsearch the bibliographies and undertake citation searches of the selected papers. Quality appraisal will be undertaken using the Appraisal of Guidelines for Research and Evaluation version II instrument for the clinical guidelines and both A MeaSurement Tool to Assess Systematic Reviews and Risk of Bias in Systematic Reviews tools for the systematic reviews. A narrative synthesis approach will be used to assess the evidence of extracted data, primarily taking account of quality appraisal and recency of publication.
Discussion: The synthesis of evidence will determine best practice for OCC early detection/screening by primary care dental healthcare professionals and will evaluate the relationship between clinical guidelines and the evidence base available from systematic reviews in this area
Evaluation of dental therapists undertaking dental examinations in a school setting in Scotland
Objective: To measure agreement between dental therapists and the
Scottish gold-standard dentist undertaking National Dental Inspection
Programme (NDIP) examinations. Methods: A study of interexaminer
agreement between 19 dental therapists and the national gold-standard dentist
was carried out. Pre-calibration training used the caries diagnostic criteria and
examination techniques agreed by the British Association for the Study of
Community Dentistry (BASCD). Twenty-three 5-year-old children (Primary 1)
and 17 11-year-old children (Primary 7) children were examined. Agreement
was assessed using kappa statistics on d 3 mft and D 3 MFT for P1 and P7 children, sensitivity and specificity values, and kappa statistics on d 3 t/D 3 T and
ft/FT. Calibration data on P1 and P7 children from 2009–2012 involving
dentists as examiners were used for comparison. Economic evaluation was
undertaken using a cost minimization analysis approach. Results: The mean
kappa score was 0.84 (SD 0.07) ranging from 0.69 to 0.94. All dental therapists
scored good or very good agreement with the gold-standard dentist. This
compares with historic NDIP calibration data with dentists, against the same
gold-standard dentist, where the mean kappa value was 0.68 (SD 0.22) with a
range of 0.35-1.00. The mean sensitivity score was 0.98 (SD 0.04) (range 0.88-1.0)
and mean specificity score was 0.90 (SD 0.06) (range 0.78-0.96). Health
economic analysis estimated that salary costs would be 33.6% lower if dental
therapists were substituted for dentists in the year 2013, with an estimated
saving of approximately £103 646 per annum on the national budget.
Conclusion: We conclude that dental therapists show a high level of
interexaminer agreement, and with the appropriate annual training and
calibration, they could undertake dental examinations as part of the NDIP
programme
Theory of Pump Depletion and Spike Formation in Stimulated Raman Scattering
By using the inverse spectral transform, the SRS equations are solved and the
explicit output data is given for arbitrary laser pump and Stokes seed profiles
injected on a vacuum of optical phonons. For long duration laser pulses, this
solution is modified such as to take into account the damping rate of the
optical phonon wave. This model is used to interprete the experiments of Druhl,
Wenzel and Carlsten (Phys. Rev. Lett., (1983) vol. 51, p. 1171), in particular
the creation of a spike of (anomalous) pump radiation. The related nonlinear
Fourier spectrum does not contain discrete eigenvalue, hence this Raman spike
is not a soliton.Comment: LaTex file, includes two figures in LaTex format, 9 page
Intra-individual movement variability during skill transitions: A useful marker?
Applied research suggests athletes and coaches need to be challenged in knowing when and how much a movement should be consciously attended to. This is exacerbated when the skill is in transition between two more stable states, such as when an already well learnt skill is being refined. Using existing theory and research, this paper highlights the potential application of movement variability as a tool to inform a coach’s decision-making process when implementing a systematic approach to technical refinement. Of particular interest is the structure of co-variability between mechanical degrees-of-freedom (e.g., joints) within the movement system’s entirety when undergoing a skill transition. Exemplar data from golf are presented, demonstrating the link between movement variability and mental effort as an important feature of automaticity, and thus intervention design throughout the different stages of refinement. Movement variability was shown to reduce when mental effort directed towards an individual aspect of the skill was high (target variable). The opposite pattern was apparent for variables unrelated to the technical refinement. Therefore, two related indicators, movement variability and mental effort, are offered as a basis through which the evaluation of automaticity during technical refinements may be made
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