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21.
Quality and patient safety are terms that both providers and recipients of healthcare are very familiar with. Accreditation is another term that is closely linked to quality and patient safety. Audit is a systematic, independent, and documented process for obtaining evidence and evaluating it objectively to determine the extent to which audit criteria are fulfilled. Accreditation and audit are integral components of the same process. Three different types of audit are well recognized—internal, external, and co-operative. Reading of relevant documents, observation of laboratory practices, and asking open-ended probing questions are important auditing techniques. For auditing to be successful, experienced, qualified, and well trained auditors are essential. Furthermore, the auditor should be open-minded, not prejudiced, a team player and effective communicator, both in writing and verbally. In many instances, the emphasis for seeking laboratory accreditation has shifted from building quality systems—to produce reliable results and ensure patient safety—to just passing the inspection. Recently, the emphasis for laboratory quality improvement has been placed on pre and post-analytical processes in preference to analytical quality. The analytical quality of laboratory results is still far from ideal and it may be detrimental if less emphasis is placed on this aspect of laboratory medicine. Auditing or on-site inspection as a regulatory tool does not work or present a realistic picture of laboratory quality. A continuous quality improvement approach will help laboratories to build quality into their systems. Presented at the Conference “Excellence in Laboratory Medicine”, November 2007, Al Ain, United Arab Emirates.  相似文献   
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We constructed six new models to analyze the DNA sequences. First, we regarded a DNA primary sequence as a random process in t and gave three ways to define nucleotides' random distribution functions. We extracted some parameters from the linear model and analyzed the changes of the nucleotides' distributions. In order to facilitate the comparison of DNA sequences, we proposed two ways to measure their similarities. Finally, we compared the six models by analyzing the similarities of the DNA primary sequences presented in Table 1 and selected the optimal one.  相似文献   
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Reaction of the potassium salt of N‐thiophosphorylated thiourea α‐naphthylNHC(S)NHP(S)(OiPr)2 ( HL ) with Cu(PPh3)3I in aqueous EtOH/CH2Cl2 leads to the mononuclear complex [Cu(PPh3)2L–S,S′]. By using copper(I) iodide instead ofCu(PPh3)3I, the polynuclear complex [Cun(L–S,S′)n] was obtained. The structures of these compounds were investigated by elemental analysis, 1H and 31P{1H} NMR and IR spectroscopy. The crystal structures of HL and Cu(PPh3)2L were determined by single‐crystal X‐ray diffraction.  相似文献   
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We find a necessary and sufficient conditions on a sequence
for the existence of an acyclic molecular graph G such that exactly m ij edges connect vertices of degree i and j. We use this result together with two additional results to make an algorithm that generates all the sequences
such that a molecular acyclic graph exists with exactly m ij edges connecting vertices of degree i and j. This algorithm is utilized to compare discriminative properties of the Zagreb index and the modified Zagreb index, and it is found that the modified Zagreb index is more discriminative then the Zagreb index.  相似文献   
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We computed the leading order Wilson coefficients relevant to all the exclusive \(b\rightarrow s\ell ^+\ell ^-\) decays in the framework of the two Higgs doublet model (2HDM) with a softly broken \(\mathbb {Z}_2\) symmetry by including the \(\mathcal {O}(m_b)\) corrections. We elucidate the issue of appropriate matching between the full and the effective theory when dealing with the (pseudo-)scalar operators for which keeping the external momenta different from zero is necessary. We then make a phenomenological analysis by using the measured \({\mathcal {B}}(B_s\rightarrow \mu ^+\mu ^-)\) and \({\mathcal {B}}(B\rightarrow K \mu ^+\mu ^-)_{\mathrm {high}-q^2}\), for which the hadronic uncertainties are well controlled, and we discuss their impact on various types of 2HDM. A brief discussion of the decays with \(\tau \)-leptons in the final state is provided too.  相似文献   
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The title compound has been synthesized under solvothermal conditions by reacting vanadium(V) oxytriisopropoxide with terephthalic acid in N,N-dimethylformamide. A combination of synchrotron powder diffraction, infrared spectroscopy, scanning and transmission electron microscopy, and thermal and chemical analysis elucidated the chemical, structural and microstructural features of a new 2D layered inorganic-organic framework. Due to the low-crystallinity of the final material, its crystal structure has been solved from synchrotron X-ray powder diffraction data using a direct space global optimization technique and subsequent constraint Rietveld refinement. [V(4)O(4)(OH)(2)(O(2)CC(6)H(4)CO(2))(4)]·DMF crystallizes in the monoclinic system (space group P2/m (No. 10)); cell parameters: a = 20.923(4) ?, b = 5.963(4) ?, c = 20.425(1) ?, β = 123.70(6)°, V = 2120.1(9) ?(3), Z = 2. The overall structure can be described as an array of parallel 2D layers running along [-101] direction, consisting of two types of vanadium oxidation states and coordination polyhedra: face-shared trigonal prisms (V(4+)) and distorted corner-shared square pyramids (V(5+)). Both configurations form independent parallel chains oriented along the 2-fold symmetry crystallographic b-axis mutually interlinked with terephthalate ligands in a monodentate mode perpendicular to it. The morphology of the compound exhibits long nanofibers, with the growth direction along the layered [-101] axis. The magnetic susceptibility measurements show that the magnetic properties of [V(4)O(4)(OH)(2)(O(2)CC(6)H(4)CO(2))(4)]·DMF can be described by a linear antiferromagnetic chain model, with the isotropic exchange interaction of J = -75 K between the nearest V(4+) neighbours of S = 1/2.  相似文献   
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This article is devoted to a further development of the passive linear continuous time invariant s/s (state/signal) systems theory. The main focus is on the connections between certain symmetry properties (such as reality and reciprocity) of the external characteristics of a s/s system and the respective symmetry of the evolution of the inner state of the system. These connections are investigated for the following classes of passive s/s systems: simple conservative, controllable energy preserving, observable co-energy preserving, optimal, ?-optimal, and minimal balanced, out of which the last three are introduced and studied here for the first time. In each of these six classes a s/s system is defined by its external characteristics up to unitary similarity. Our results are connected with the respective results in the input/state/output systems theory, where the external characteristics of a system are scattering, impedance or transmission matrices.  相似文献   
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