bluuebunny/crossref_metadata_2025 huggingface dataset:
Six Sigma in a Dutch Hospital: Does It Work in the Nursing Department?
Authors: van den Heuvel Jaap , Does Ronald J. M. M. , Vermaat M. B. (Thijs)
Published: July 2004

The Red Cross Hospital is a medium‐sized general hospital with 385 beds, located in Beverwijk, The Netherlands. It also has a freestanding National Burn Care Centre. The Red Cross Hospital was the first hospital in The Netherlands with a quality system based on ISO 9000. At the end of 2001 the hospital started implementing Six Sigma. The process began with Executive Training for management and Green Belt (GB) training for 16 middle managers and other staff. Seven GB projects were started in the areas of accounts receivable, patient logistics, invoicing, medication, temporary workers, and length of stay in hospital. In February 2003 the final review of the first group was done and savings appeared to be three times higher than estimated beforehand. At present (May 2004) the fourth group of Green Belts has been trained. In this paper we briefly explain that Six Sigma was the next logical step in the quality approach of the hospital. We also discuss how it was implemented and we describe some case studies in the nursing departments. Copyright © 2004 John Wiley & Sons, Ltd.
Black Belt Types
Authors: Caulcutt Roland
Published: July 2004

An essential component of the Six Sigma approach to business improvement, is the training of employees for the role of process improvement specialist. These people usually have the words ‘Black Belt’ in their job title. Their role varies from company to company, but it invariably involves extensive use of statistical techniques. We suggest that some of the time devoted to statistics training could usefully be spent considering the human dynamics of improvement projects. More specifically we explore the benefits for Black Belts of understanding personality types. Copyright © 2004 John Wiley & Sons, Ltd.
A Multi‐scale Approach to Functional Signature Analysis for Product End‐of‐life Management
Authors: Di Bucchianico A. , Figarella T. , Hulsken G. , Jansen M. H. , Wynn H. P.
Published: July 2004

Nowadays, electronic products tend to be economically outdated before their technical end of life has been reached. The ability to analyze and predict the (remaining) technical life of a product would make it possible either to re‐use sub‐assemblies in the manufacturing process of new products, or to design products for which the technical and economical life match. This requires models to predict and monitor performance degradation profiles. In this paper we report on designed experiments to obtain such models. We show how wavelet analysis can be used to extract features from electrical signals. These features are analyzed using Analysis of Variance in order to establish relations between these features and performance degradation. Copyright © 2004 John Wiley & Sons, Ltd.
Experimentation with Randomization Restrictions: Targeting Practical Implementation
Authors: Simpson James R. , Kowalski Scott M. , Landman Drew
Published: July 2004

Randomization, one of the fundamental principles of statistically designed experiments, is not always easy to implement in practice. In fact, many industrial settings involve factors of interest that are difficult to change, requiring some modification to a completely randomized test sequence. Practical issues associated with restricted randomization commonly arise regarding design efficiencies, design requirements for error estimation, overall ease of software‐assisted analysis, required replication, tests for nonlinearity, and sequential testing plans. The purpose of this paper is to deal directly with these roadblocks to efficient and effective experimentation under randomization restrictions. The general approach involves modifying standard split‐plot designs with appropriate augmentation followed by a two‐stage model building method using a standard general linear model framework. An alternative procedure for analyzing two‐level factorial split‐plot designs is provided for commonly occurring situations involving more than one hard‐to‐change factor. The proposed methods were developed and implemented in conducting experiments for wind tunnel applications. These tests serve as case studies for the paper. We also suggest possible methods for limiting the replication required for estimating whole plot error. Copyright © 2004 John Wiley & Sons, Ltd.
Comparing Multi‐response Design Methods with Mixed Responses
Authors: Kros John F. , Mastrangelo Christina M.
Published: July 2004

The multi‐response optimization process is commonly applied to engineering design problems involving more than one quality characteristic of interest. Define quality characteristics as output responses that fall into three general categories: larger‐the‐better (LTB), smaller‐the‐better (STB), and nominal‐the‐best (NTB). In the multi‐response optimization process, the objective is to define a set of input factors that, when combined, provide the optimal overall response. This paper investigates the relationship between response types when they are mixed (i.e. LTB, and/or STB, and/or NTB) and the choice of approach. The paper demonstrates that the mix of response types impacts the choice of final input parameters and response levels. In addition, the choice of an additive versus a multiplicative approach may adversely impact the response relationship. That is, it may produce two optimal combinations of factor settings or drive responses away from their target values and toward their extreme values. Copyright © 2004 John Wiley & Sons, Ltd.
Using Computer Modeling to Optimize Cost and Maintain Performance Constraints for the Production of Aircraft Turbine Engines
Authors: Sheldon Karl E. , Anderson‐Cook C. M. , O'Brien W. F.
Published: July 2004

The use of computer models and simulation can be an effective way of gaining valuable information about a variety of engineering systems. In this paper, quadratic polynomial models are used to estimate gas turbine engine performance models in an extensive simulation. The goal of the simulation is maximize the tolerances on a number of engine design features, while still producing an engine that will have an overall 3‐sigma (99.74%) pass rate on a number of geometric and performance constraints. The tolerances are maximized by using an optimization routine to determine the greatest allowable standard deviations (all with equal weights) and thus help to reduce engine‐manufacturing cost. Details are provided about how the models and simulation were constructed, as well as how information about the system was extracted from simulation results. A comparison of current production guidelines is made with those suggested by the study to show how system improvements can be achieved. Copyright © 2004 John Wiley & Sons, Ltd.
Identification of novel cannabinoid receptor ligands via evolutionary de novo design and rapid parallel synthesis
Authors: Rogers‐Evans Mark , Alanine Alexander I. , Bleicher Konrad H. , Kube Dagmar , Schneider Gisbert
Published: July 2004

A rapid entry to novel and patentable cannabinoid receptor (CB‐1) ligands has been identified using computer‐based de novo design in combination with parallel synthesis. Small targeted compound arrays were readily prepared from the designs yielding active hit rates of 6% and 10%, respectively. This represents a hit rate enrichment of up to two orders of magnitude compared with corporate compound collections and is the first report of the application of the TOPAS algorithm for the de novo design of GPCR ligands.
Prediction of Carbonic Anhydrase Activation by Tri‐/Tetrasubstituted‐pyridinium‐azole Compounds: A Computational Approach Using Novel Topochemical Descriptor
Authors: Bajaj Sanjay , Sambi S. S. , Madan A. K.
Published: July 2004

A novel highly discriminating adjacency‐cum‐distance based topochemical descriptor, termed as Superadjacency topochemical index, has been derived and its discriminating power investigated with regard to activation of Carbonic anhydrase (CA) isozyme‐I by tri‐/tetrasubstituted‐pyridinium‐azole compounds. The new index is not only sensitive to the presence of heteroatoms but also overcomes the problem of degeneracy of many topological descriptors. The discriminating power of Superadjacency topochemical index was found to be far superior when compared with that of distance based Wiener's index and adjacency based Molecular connectivity index. The values of Wiener's index, path‐one Molecular connectivity index and Superadjacency topochemical index of each of the 42 substituted‐pyridinium‐azole compounds comprising the dataset were computed. Resultant data was analyzed and suitable models developed after identification of the active ranges. Subsequently, a biological activity was assigned to each of the compounds involved in the dataset using these models, which was then compared with the reported activation constants for Carbonic Anhydrase isozyme‐I. Excellent correlations were observed between the activation constants of CA isozyme‐I and all the topological/topochemical descriptors. The overall accuracy of prediction was about 91% for models based upon both Molecular connectivity index as well as Wiener's index, and 96% for model based upon Superadjacency topochemical index. Surprisingly, the accuracy of prediction in the active range was found to be 100% in all the models. Thus the proposed index offers a vast potential for structure‐activity/structure‐property studies.
QSAR of Human Steroid 5α‐Reductase Inhibitors: Where are the differences between isoenzyme type 1 and 2?
Authors: Hutter Michael C. , Hartmann Rolf W.
Published: July 2004

Quantitative Structure Activity Relationships have been established for inhibitors of human steroid 5α‐reductase including 6‐azasteroids and non‐steroidal compounds. From the applied descriptors, those related to the molecular geometry, electronic properties, and the electrostatic surface were derived from semi‐empirical AM1 calculations. A chemical reaction as part of the inhibitory action is indicated by the presence of the ionization potential in the descriptor space. Strong similarities between the variables for the prediction of the binding affinity to the type 1 and IC50 values for the type 2 isoform of the 5α‐reductase were observed. The most pronounced differences in the linear regression QSAR equations were found for the descriptors accounting for the hydrogen‐bonding interaction, suggesting a different hydrogen‐bonding pattern in the binding pocket of both isoforms. Furthermore, the topological indices together with the surface related descriptors point towards a lower content of aromatic amino acids in the binding site of the type 2 isoenzyme. Consequences for the design of new inhibitors are discussed.
The exclusion principle for interacting electrons: Kohn–Sham versus Thomas–Fermi
Authors: Nesbet R. K.
Published: July 2004

Many anomalies and paradoxes in density‐functional theory arise from the assumption that an exact mean‐field theory of electrons requires only local potential functions. It is shown here that this assumption arises from a logical hiatus in deriving orbital‐based Kohn–Sham theory, which incorporates the exclusion principle for electrons, from density‐based Hohenberg–Kohn theory, which does not. The inconsistencies are removed by building the exclusion principle into density‐based theory from the outset. This logic replaces any implication regarding exact local potential functions by explicit specification of nonlocal potentials determined by exact N‐electron theory. These general results are examined here in the unrestricted Hartree–Fock variational model, using a two‐electron atom in its lowest triplet state 1s2s 3S as a test case to illustrate the implied inconsistencies and their resolution. It is shown that implications of the unrestricted Hartree–Fock model are not modified if overlap products are included in its variational functional. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Isospectral orthogonal polynomials from the Darboux transforms
Authors: Peña J. J. , Morales J. , Zamora‐Gallardo E. , García‐Ravelo J.
Published: July 2004

Orthogonal polynomials (OP) are used in many branches of the mathematical and physical sciences; in particular they are part of the eigenfunctions of quantum chemical (QC) potential models. Recently, in the search for new solvable potentials to be useful in QC applications, the use of supersymmetry (SUSY) and Hamiltonian intertwining methods have shown the existence of isospectral potential partners. Also, it has been proved that SUSY is equivalent to the standard Darboux transform (DT) applied to Sturm–Liouville‐type problems. Consequently, because of the similarity between the differential equations of OP and of SL, we consider the application of the standard and generalized DT to find the isospectral OP that are partners of the standard one. To attain this purpose, we use a pair of transformations, a point canonical and a gauge, to convert the SL differential equation into a Schrödinger‐like equation allowing OP solutions. As a useful application of our proposal, we consider some of the most important OP by obtaining the generalized isospectral OP partners. Also, we shown the associated isospectral QC potentials for each of the orthogonal polynomials considered in this work. The proposed procedure can be used to obtain new orthogonal polynomials as well as to find new solvable QC potential models. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Theoretical studies on many‐band effects in superconductivity and magnetism
Authors: Nagao Hidemi
Published: July 2004

We present a two‐dimensional two‐sublattice system to investigate two‐band effects in magnetism and superconductivity. The spin susceptibility of the sublattice system is calculated, and the expression of the effective exchange integral in Heisenberg model for the sublattice is derived in the framework of the Hubbard model. We find the possibility of the appearance of ferromagnetic order around half‐filling in a two‐band system. Within the extended Hubbard model, a coupled gap equation for the two‐band superconductivity is also derived by using a mean‐field approximation. The results suggest that the superconducting order becomes larger by the pair‐scattering process. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Brueckner orbitals, Dyson orbitals, and correlation potentials
Authors: Ortiz J. V.
Published: July 2004

One‐electron, correlation potentials are closely related to the concepts of Brueckner orbitals and Dyson orbitals. Brueckner orbitals arise from fulfillment of a maximum‐overlap condition between a reference, Slater determinant and the many‐electron wavefunction. This condition may be used to define an energy‐independent, correlation potential for a given state. Dyson orbitals, in contrast, are associated with electron binding energies and are obtained from a pseudoeigenvalue problem with an energy‐dependent, correlation potential. The Brueckner doubles (BD)‐T1 approximation of the electron propagator employs an approximate Brueckner determinant in its reference state. Dyson orbitals generated with this approximation are expressed in the Brueckner orbital basis. An application of this approximation to the photoelectron spectrum of Al3O enables the assignment of peaks to distinct isomers. Dyson orbitals for the lowest electron detachment energies have high overlaps with occupied Brueckner orbitals that diagonalize the corresponding Fock operator. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Theoretical studies on effective exchange integrals using spin correlation function analysis and magnetic effective density functional (MEDF) method
Authors: Kitagawa Y. , Yamanaka S. , Takeda R. , Shoji M. , Koizumi K. , Nishiyama Y. , Maruno Y. , Kawakami T. , Okumura M. , Yamaguchi K.
Published: July 2004

New schemes for effective exchange integrals (Jab) and approximate spin‐projected energies for low spin states (EAPLS) were examined on simple two‐site radical models. These schemes are based on Hubbard model and include ionic term in wavefunction. By estimation of expectation values of spin correlation function, those schemes could directly calculate Jab and EAPLS values without the approximation that on‐site spins for high‐spin (HS) state was equivalent to one of low‐spin (LS) state. Calculated Jab values by new scheme were larger than conventional ones in short spin–spin distance, suggesting an importance of the on‐site spins and ionic term. On the other hand, new EAPLS values were similar to conventional ones. Estimation methods for new Jab and EAPLS also were derived by using HS state energy, LS state energy, and 〈Ŝ2〉LS analytically. To correct dynamical correlation, magnetic effective density functional (MEDF) method was successfully applied to calculate new Jab and EAPLS. © 2004 Wiley Periodicals, Inc. Int J Quantum Chem, 2004
Risk, regulation and the right to know: exploring the impacts of access to information on the governance of environmental risk
Authors: Gouldson Andy
Published: July 2004

Within the context of broader debates on the potential of more open, inclusive and deliberative approaches to decision‐making, this paper examines the influence that enhanced access to environmental information has had on the governance of industry in the UK. After considering the extent to which information on emissions from industrial sites is practicably accessible to stakeholders, it examines the strategies that the different actors have adopted as a response to the provision of enhanced access to environmental information. In so doing, it highlights the pros and cons of greater transparency and more open engagement from the perspective of regulators, industry, community and pressure groups. It then assesses the impacts of access to information, both on the governance networks through which the different actors interact in an attempt to influence the emissions of the chemicals sector and on the environmental outcomes associated with these networks. It concludes that the provision of access to information has been associated with the emergence of new forms of engagement between regulators, industry and stakeholder groups and that this has coincided with (but has not been the main cause of) dramatic improvements in the environmental performance of the associated firms. Copyright © 2004 John Wiley & Sons, Ltd and ERP Environment.
Use of QUASES™/XPS measurements to determine the oxide composition and thickness on an iron substrate
Authors: Grosvenor A. P. , Kobe B. A. , McIntyre N. S. , Tougaard S. , Lennard W. N.
Published: July 2004

QUASES™ Analyze and Generate were used to model the extrinsic loss structures for XPS spectra of oxide films grown on iron in such a way that their thickness and structure could be determined. The Generate program used in conjunction with spectra of model iron oxides allowed for both magnetite (Fe3O4) and maghaemite (γ‐Fe2O3) structures to be identified in all films studied. These structures were identified as overlying layers in the oxide films and were usually intermixed at their interface. The absence of other iron oxide structures within the film could be tested based on their goodness of fit to the experimental spectrum. Comparison of the thickness values obtained using Generate with those found using nuclear reaction analysis suggested that the Generate results were higher by 20%. This difference likely resulted from the use of a calculated inelastic mean free path value for Fe 2p electrons in the Generate calculation rather than using the real attenuation length. For oxide films whose thickness approached 10 nm, the QUASES™ results for photoelectron spectra obtained with a Zr achromatic x‐ray source were compared with those from the standard Al monochromatic source. In this particular case, the oxide thicknesses obtained using Generate and Analyze were found to be more consistent when the Zr source was used. Copyright © 2004 John Wiley & Sons, Ltd.
Photoelectron core levels for enargite, Cu3AsS4
Authors: Pratt Allen
Published: July 2004

The mineral chemistry of enargite surfaces and near‐surfaces prepared by fracture within an ultrahigh vacuum are investigated using XPS and synchrotron radiation XPS (SRXPS). The purpose of the study is to identify surface core‐level line positions in high‐resolution photoelectron spectra. The XPS spectra obtained using monochromatic Al Kα radiation show that there are near‐identical monosulphide line positions in S 2p spectra for the As–S and Cu–S bonds in enargite. The SRXPS spectra for sulphur are remarkably similar to the XPS spectra for sulphur, showing that there is minimal difference in the chemical environment between sulphur atoms at the surface and in the mineral matrix. The Cu 2p XPS data have only cuprous contributions and a minor surface contribution. The surface Cu contribution is observed as a high‐binding‐energy tail in the Cu 2p3/2 spectrum. The As 3d data for both XPS and SRXPS show contributions from arsenic atoms at the surface and in the bulk mineral matrix. The surface contribution is distinct and is found 1 eV below the bulk contribution. The results of the study suggest that, following fracture, the enargite surface is reorganized in such a manner that the surface is characterized by protrusions of individual arsenic atoms. Copyright © 2004 John Wiley & Sons, Ltd.
On sample size for sensitivity and specificity in prospective diagnostic accuracy studies
Authors: Li Jialiang , Fine Jason
Published: July 2004

The design of a study of disease screening tests may be based on hypothesis tests for the sensitivity and specificity of the tests. The case‐control study requires knowledge of the disease status of patients at the time of enrollment. This may not be possible in a prospective setting, when the gold standard is obtained subsequent to the initial screening and the number of diseased individuals is random and can not be fixed by design. Several ad hoc procedures for determining the total sample size are commonly used by practitioners, for example, the prevalence inflation method. The properties of these methods are not well understood. We develop a formal method for sample size and power calculations based on the unconditional power properties of the test statistics. The approach provides novel insights into the behaviour of the commonly used methods. We find that the ad hoc prevalence inflation method may serve as a useful approximation to our rigorous framework for sample size determination in the prospective set‐up. The design of a large population‐based study of mammography for breast cancer screening illustrates the key issues. Copyright © 2004 John Wiley & Sons, Ltd.
Hierarchical modelling of small area and hospital variation in short‐term prognosis after acute myocardial infarction A longitudinal study of 35‐ to 74‐year‐old men in Denmark between 1978 and 1997
Authors: Rasmussen Søren
Published: July 2004

Models for analysis of trends in hospital and small area variation in case fatality after acute myocardial infarction are presented. The data are from administrative registries in Denmark. Hierarchical modelling in a logistic regression with a Bayesian approach is used. Model selection is undertaken using the deviance and the Bayesian information criteria. There is a modest trend for hospital variation in case‐fatality rates that coincides with the introduction of new treatment strategies. This hospital variation is considerably larger than the variation at the area level. There is no trend for variation of the case‐fatality rates at the area level. Unstructured random effects slightly outperform spatially correlated random effects at the area level. Somewhat high correlations over time within hospitals and within areas were detected for the case‐fatality rates. Heavy‐tailed distributions (T‐distributions) could be an alternative for the random effect distribution in data from administrative registries and compete in the model selection with the normal distribution in this study. Copyright 2004 John Wiley & Sons, Ltd.
Validation and updating of predictive logistic regression models: a study on sample size and shrinkage
Authors: Steyerberg Ewout W. , Borsboom Gerard J. J. M. , van Houwelingen Hans C. , Eijkemans Marinus J. C. , Habbema J. Dik F.
Published: July 2004

A logistic regression model may be used to provide predictions of outcome for individual patients at another centre than where the model was developed. When empirical data are available from this centre, the validity of predictions can be assessed by comparing observed outcomes and predicted probabilities. Subsequently, the model may be updated to improve predictions for future patients.

As an example, we analysed 30‐day mortality after acute myocardial infarction in a large data set (GUSTO‐I,n= 40 830). We validated and updated a previously published model from another study (TIMI‐II,n= 3339) in validation samples ranging from small (200 patients, 14 deaths) to large (10 000 patients, 700 deaths). Updated models were tested on independent patients. Updating methods included re‐calibration (re‐estimation of the intercept or slope of the linear predictor) and more structural model revisions (re‐estimation of some or all regression coefficients, model extension with more predictors). We applied heuristic shrinkage approaches in the model revision methods, such that regression coefficients were shrunken towards their re‐calibrated values. Parsimonious updating methods were found preferable to more extensive model revisions, which should only be attempted with relatively large validation samples in combination with shrinkage. Copyright © 2004 John Wiley & Sons, Ltd.
A shortened stress evaluation tool (ASSET)
Authors: Faragher E. B. , Cooper C. L. , Cartwright S.
Published: July 2004

Awareness is increasing that workplace characteristics can directly influence the physical and mental well‐being of employees, adversely affecting an organization's overall performance. As the effect of work‐related stress on employee health is of particular concern, many companies are looking to develop stress risk assessment programmes. However, the measurement instruments commonly used to examine workplace stressors are long, complex and developed primarily for white‐collar workers—making evaluations expensive and potentially inaccurate for most employee groups. An alternative, two‐stage, risk assessment process is proposed, whereby a short questionnaire is used initially to screen all employees and then conventional risk assessment tools used to evaluate in detail just those individuals identified as having a potential stress problem. The ASSET questionnaire was developed as a short instrument suitable for the first stage of this process. The three main sections of the questionnaire measure employee perceptions of their job, organizational commitment and employee health. Tests involving 9196 employees in 10 public and private sector organizations within the British Isles found ASSET to be quick and easy to complete, generating a high response rate. It has a small number of reliable factors for ease of interpretation, and has excellent validity. Copyright © 2004 John Wiley & Sons, Ltd.
Improving design quality using meta‐pattern transformations: a metric‐based approach
Authors: Tahvildari Ladan , Kontogiannis Kostas
Published: July 2004

Improving the design quality of large object‐oriented systems during maintenance and evolution is widely regarded as a high‐priority objective. Furthermore, for such systems that are subject to frequent modifications, detection and correction of design defects may easily become a very complex task that is even not tractable for manual handling. Therefore, the use of automatic or semi‐automatic detection and correction techniques and tools can assist reengineering activities. This paper proposes a framework whereby object‐oriented metrics can be used as indicators for automatically detecting situations for particular transformations to be applied in order to improve specific design quality characteristics. The process is based both on modeling the dependencies between design qualities and source code features, and on analyzing the impact that various transformations have on software metrics that quantify the design qualities being improved. Copyright © 2004 John Wiley & Sons, Ltd.
Tissue Doppler gated (TDOG) dynamic three‐dimensional ultrasound imaging of the fetal heart
Authors: Brekke S. , Tegnander E. , Torp H. G. , Eik‐Nes S. H.
Published: July 2004

Dynamic three‐dimensional (3D) ultrasound imaging of the fetal heart is difficult due to the absence of an electrocardiogram (ECG) signal for synchronization between loops. In this study we introduce tissue Doppler gating (TDOG), a technique in which tissue Doppler data are used to calculate a gating signal. We have applied this cardiac gating method to dynamic 3D reconstructions of the heart of eight fetuses aged 20–24 weeks.

The gating signal was derived from the amplitude and frequency contents of the tissue Doppler signal. We used this signal as a replacement for ECG in a 3D‐volume reconstruction and visualization, utilizing techniques established in ECG‐gated 3D echocardiography.

The reliability of the TDOG signal for fetal cardiac cycle detection was experimentally investigated. Simultaneous recordings of tissue Doppler of the heart and continuous wave (CW) spectral Doppler of the umbilical artery (UA) were performed using two independent ultrasound systems, and the TDOG signal from one system was compared to the Doppler spectrum data from the other system. Each recording consisted of a two‐dimensional (2D) sector scan, transabdominally and slowly tilted by the operator, covering the fetal heart over approximately 40 cardiac cycles. The total angle of the sweep was estimated by recording a separate loop through the center of the heart, in the elevation direction of the sweep.

3D reconstruction and visualization were performed with the EchoPAC‐3D software (GE Medical Systems). The 3D data were visualized by showing simultaneous cineloops of three 2D slices, as well as by volume projections running in cineloop.

Synchronization of B‐mode cineloops with the TDOG signal proved to be sufficiently accurate for reconstruction of high‐quality dynamic 3D data. We show one example of a B‐mode recording with a frame rate of 96 frames/s over 20 seconds. The reconstruction consists of 31 volumes, each with 49 tilted frames. With the fetal heart positioned 5–8 cm from the transducer, the sampling distances were approximately 0.15 mm in the beam direction, 0.33° ∼ 0.37 mm azimuth and 0.45° ∼ 0.51 mm elevation. From this single dataset we were able to generate a complete set of classical 2D views (such as four‐chamber, three‐vessel and short‐axis views as well as those of the ascending aorta, aortic and ductal arches and inferior and superior venae cavae) with high image quality adequate for clinical use. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Disappearance of enlarged nuchal translucency before 14 weeks' gestation: relationship with chromosomal abnormalities and pregnancy outcome
Authors: Müller M. A. , Pajkrt E. , Bleker O. P. , Bonsel G. J. , Bilardo C. M.
Published: July 2004

Objective

The aim of this study was to investigate the natural course of enlarged nuchal translucency (NT) and to determine if its disappearance before 14 weeks' gestation is a favorable prognostic sign in relation to fetal karyotype and pregnancy outcome.

Methods

A total of 147 women with increased NT (> 95th centile) at first measurement were included in this study. A second measurement was performed in all cases, at an interval of at least 2 days. Both measurements were taken between 10 + 3 and 14 + 0 weeks. All women underwent chorionic villus sampling or amniocentesis for subsequent karyotyping. In those women with a normal karyotype, a fetal anomaly scan was performed at 20 weeks' gestation. Pregnancy outcome was recorded in all cases. The finding of persistent or disappearing NT enlargement was analyzed in relation to fetal karyotype and pregnancy outcome.

Results

Of the 147 paired measurements, NT remained enlarged at the second measurement in 121 (82%) cases. An abnormal karyotype was found in 35% of these cases. In 26 (18%) fetuses the NT measurement was found to be below the 95th percentile at the second measurement and in only two of them an abnormal karyotype was found (8%). In the 103 chromosomally normal fetuses an adverse outcome (i.e. fetal loss or structural defects) was recorded in 22 fetuses with persistent enlargement (28%) and in four fetuses with disappearing enlargement (17%).

Conclusions

Disappearance of an enlarged NT before 14 weeks' gestation is not a rare phenomenon and seems to be a favorable prognostic sign with respect to fetal karyotype. Overall, no significant difference in pregnancy outcome was found between chromosomally normal fetuses with persisting or disappearing NT enlargement. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Prenatal diagnosis of hemifacial microsomia and ipsilateral cerebellar hypoplasia in a fetus with oculoauriculovertebral spectrum
Authors: Martinelli P. , Maruotti G. M. , Agangi A. , Mazzarelli L. L. , Bifulco G. , Paladini D.
Published: July 2004

Oculoauriculovertebral spectrum, or Goldenhar syndrome, is characterized by varying degrees of prevalently unilateral underdevelopment of craniofacial structures (orbit, ear, mandible) and spinal anomalies. We report the prenatal ultrasonographic diagnosis made at 24 weeks' gestation in a family with a negative history. The prenatal diagnosis was suspected due to the presence of marked hemifacial microsomia and moderate ipsilateral cerebellar hemisphere hypoplasia in the absence of facial clefting. Copyright © 2004 ISUOG. Published by John Wiley & Sons, Ltd.
Phosphorpentachlorid und Trichlorphenol — eine 31P‐NMR‐Studie [1]
Authors: Gloede Jörg , Waschke Regina , Pieper Ursula
Published: July 2004

Phosphorpentachlorid reagiert mit 2, 4, 6‐Trichlorphenol in Abhängigkeit vom Verhältnis der Edukte zu 2, 4, 6‐Trichlorphenoxy‐chlorphosphorane.
The Molecular Structures of Di(1‐cyclohepta‐2, 4, 6‐trienyl)sulfane, S(C7H7)2, and its 1:1 Diels‐Alder Adduct with Maleic Anhydride
Authors: Herberhold Max , Liu Jinnan , Milius Wolfgang
Published: July 2004

The reaction of the olefinic thioether S(C7H7)2 (1) with maleic anhydride (a), maleimide (b) and N‐phenyl maleimide (c) leads to 1:1 Diels‐Alder adducts (4a‐c) in which one of the two 1‐cyclohepta‐2, 4, 6‐trienyl substituents has remained intact. In the solid state, both S(C7H7)2 (1) and its 1:1 adduct with maleic anhydride (4a) contain the C7H7 substituents in the boat conformation in axial attachment to the sulfur atom. Addition of maleic anhydride (a) to 1 results in flattening of the remaining boat‐shaped 1‐cyclohepta‐2, 4, 6‐trienyl ring and in a slight increase of the angle at the central sulfur atom from 100.7(1)° in 1 to 103.2(2)° and 102.7(2)° in the two independent molecules 4a and 4a′, respectively, of the adduct.
2‐Dialkyl‐ and 2‐tert‐Butylphenylphosphinophenol(ate) Nickel and Palladium Complexes: Control of E/Z‐Configuration in Bis(P∩O—‐chelates) and Activation of the Nickel Complexes for Polymerization of Ethylene
Authors: Heinicke Joachim , Köhler Martin , Peulecke Normen , Keim Wilhelm , Jones Peter G.
Published: July 2004

Nickel bis(2‐dialkylphosphinophenolates), detected as the spent form of organonickel 2‐dialkylphosphinophenolate catalysts for the polymerization of ethylene, were studied. In contrast to the impact of the P‐basicity on the catalyst properties, the configuration of bis(2‐dialkylphosphinophenolate) nickel is controlled only by steric effects. Small alkyl substituents favor, as do phenyl groups, square planar cis‐bis(P∩O—‐chelates) while more bulky alkyl groups lead to trans‐isomers. Dicyclohexyl‐ and tert‐butylphenylphosphino groups give rise to borderline cases. Analogous palladium complexes show a slightly smaller effect of the metal size on the cis/trans‐control. Intermediates on the way to PdII bis(P∩O—‐chelates), trans‐dichloro‐bis(phosphinophenol)‐ and chloro‐phosphinophenol phosphinophenolate palladium(II) complexes could be isolated; the crystal structure of one of the latter was determined. The nickel bis(2‐dialkylphosphinophenolates) can be activated as polymerization catalysts, to a limited extent by NiBr2·DME and sodium hydride or triethylsilane in THF, more efficiently by nBuLi or nBuLi / NiBr2·DME.
Hydrolysis of 4‐Nitrophenyl Acetate by a μ2‐OH‐bridged Zinc Complex: Crystal Structure of [Zn(oapy)(OAc)(μ2‐OH)] and [ZnL(μ2‐SO4)]4·6H2O (oapy is 2‐aminopyridine and L is 2, 5, 8‐triaza‐1, 9‐di(2‐fluorozenzyl)nonane)
Authors: Zhu Hai‐Liang , Ma Ji‐Long , Wang Da‐Qi
Published: July 2004

Two new complexes, [Zn(oapy)(OAc)(μ2‐OH)] (1) and [ZnL(μ2‐SO4)]4·6H2O (2), were prepared and structurally characterized, where oapy is o‐aminopyridine, OAc is acetate, and L is 2, 5, 8‐triaza‐1, 9‐di(2‐fluorozenzyl)nonane. The X‐ray structure analysis reveals that 1 crystallizes in the monoclinic system with space group P21/c, with a = 8.849(9), b = 5.391(5), c = 19.733(19)Å, β = 98.467(13)°, V = 931.2(16)Å3, and Z = 4. 1 is a μ2‐OH bridged 1D chain complex along b. The Zn2+ ion is four‐coordinated by one N atom from an oapy, and three O atoms from two hydroxyl groups and an acetate ion, leading to a distorted tetrahedral geometry of Zn2+. 2 crystallizes in space group P1¯ with a = 15.86(3), b = 17.05(3), c = 19.85(4)Å, α = 74.60(4), β = 66.93(3), γ = 65.33(4)°, V = 4456(16)Å3, and Z = 2. Compound 2 is a 1D chain‐like complex linked by μ2‐(O, O′)‐SO4 bridges. Each simplest unit of the complex is a tetranuclear zinc(II) unit. In each unit the four non‐equivalent zinc atoms, are similarly five‐coordinated by three N atoms from L and two O atoms from two sulfate bridges. The coordination geometry of two zinc atoms is trigonal bipyramidal, the other two are in square pyramidal coordination. 1 has obvious catalytic activity to hydrolysis of 4‐nitrobenyl acetate, but 2 does not.
Lanthanide(III) Amidinates with Six‐ and Seven‐Coordinate Metal Atoms
Authors: Richter Joachim , Feiling Jürgen , Schmidt Hans‐Georg , Noltemeyer Mathias , Brüser Wolfgang , Edelmann Frank T.
Published: July 2004

The crystalline lithium N, N′‐diorganoamidinates Li[PhC(NR)2] (1: R = c‐C6H11, 2: R = iPr) and Li[(CF3)3C6H2C(N‐c‐C6H11)2] (3) have been obtained by the reaction of phenyllithium or 2, 4, 6‐tris(trifluoromethyl)phenyllithium, resp., with diorganocarbodiimides R‐N=C=N‐R (R = c‐C6H11, iPr). These amidinates have been used for the synthesis of the homoleptic lanthanide(III) amidinates [PhC(N‐c‐C6H11)2]3Ln (4—6: Ln = Pr, Nd, Sm) and [PhC(NiPr)2]3Pr (7). Seven‐coordinate Lewis‐base adducts of the type [PhC(NSiMe3)2]3Ln(NCPh) (8, 9: Ln = Sm, Eu) have been prepared by addition of benzonitrile to the homoleptic precursors [PhC(NSiMe3)2]3Ln. The compounds 2 (as its THF adduct), 4, 6, 8 and 9 have been structurally characterized by single crystal X‐ray analyses.
Synthesis of the first Pentacarbonyltungsten(0) Complexes with P‐Pentamethyl‐cyclopentadienyl‐substituted 1H‐Phosphirene Ligands: Crystal Structure of [{(Me5C5PC(H)=CPh}W(CO)5]
Authors: Streubel Rainer , Bode Maren , Schiemann Udo , Wismach Cathleen , Jones Peter G. , Monsees Axel
Published: July 2004

The tungsten(0) complex [{Me5C5PC(Ph)=N}W(CO)5] (1) reacts upon heating with alkyne derivatives 3a—e in toluene to form benzonitrile and the complexes [{Me5C5PC(R1)=C(R2)}W(CO)5] (4a—e) (4a: R1 = OEt, R2 = H; 4b: R1 = OEt, R2 = SiMe3; 4c: R1 = Ph, R2 = H; 4d : R1 = Ph, R2 = Ph; 4e: R1, R2 = Et), which were purified by column chromatography (except 4d). In reaction of 1 with 3d the tungsten(0) complex 5, having a 2, 3‐dihydro‐1, 2, 3‐azadiphosphete ligand, is formed in a competing reaction. Spectroscopic and mass spectrometric data of complexes 4a—c, 4e and 5 are discussed. The structures of complexes 4c and 5 were determined by single‐crystal X‐ray diffraction In 4c the three‐membered ring has a C=C bond length of 1.312(3)Å and a C—P—C angle of 43.02(9)°. In 5 the P—P bond length is 2.2866(7)Å; the four‐membered ring is slightly folded (fold angle 15° about P1—C6).
A Novel Ruthenium(III) and Lithium Complex: Synthesis, Crystal Structure, and Magnetic Properties
Authors: Bai Li‐Xia , Liu Xin , Wang Wen‐Zhen , Liao Dai‐Zheng , Wang Qing‐Lun
Published: July 2004

A novel complex [Li3{μ‐(H2O)6}(H2O)6]·[RuCl6] has been synthesized and was characterized by single‐crystal X‐ray diffraction. The compound crystallizes in rhombohedral space group R3¯c, with the unit cell parameters a = b = 9.948(2)Å, c = 33.376(14)Å, γ = 120°, V = 2860.5(15)Å3, Z = 6, Dc = 1.918 Mg m—3, μ = 1.703 mm—1, R = 0.0244, wR = 0.0478. The compound consists of a cation, which contains three lithium ions linked by six bridged water molecules, and an anion, which contains a ruthenium(III) ion. The whole complex can be described as a three‐dimensional structure linked by hydrogen bonds between cation and anion. The magnetic properties of the complex have been investigated. The IR, UV‐vis and EPR spectra are studied.
Conjugation of the closo‐Borane Mercaptoundecahydrododecaborate (BSH) to a Tumour Selective Peptide
Authors: Mier Walter , Gabel Detlef , Haberkorn Uwe , Eisenhut Michael
Published: July 2004

The non‐toxic disodium mercaptoundecahydrododecaborate (BSH) is one of the most promising agents known for boron‐neutron‐capture therapy (BNCT). In order to enhance the intratumoral concentration of the boron cluster by receptor mediated endocytosis, a synthetic method for the conjugation of borane clusters to peptides was developed. A Michael addition was performed to link BSH to the thiol reactive maleimido modified Tyr3‐octreotate. Tyr3‐octreotate, synthesized by Fmoc‐solid phase peptide synthesis, is a selective ligand for somatostatin receptors. The modified boron cluster was obtained in 68 % yield after purification. Characterisation of the BSH conjugate was performed with HPLC, MALDI‐TOF and electrospray mass spectrometry. The BSH‐Tyr3‐octreotate conjugate is considered to target receptor‐positive tumours which might further improve the potential of BNCT.
[{ImCH2Br}Br]6 — eine unerwartete Käfigstruktur [1]
Authors: Kuhn Norbert , Abu‐Rayyan Ahmed , Steimann Manfred , Ströbele Markus
Published: July 2004

Die Imidazolderivate ImCH2X2 [Im = C7H12N2; X = Br (5), Cl (8)] werden durch Umsetzung des ylidartigen Olefins ImCH2 (3) mit Brom bzw. Hexachlorethan erhalten. Die Kristallstrukturanalyse von 5 zeigt das Vorliegen eines hexameren Kations mit trigonal‐antiprismatischem Br6‐Kern sowie isolierte Bromidionen. In die aus zwei Br3‐Dreiecksflächen und den zugehörigen Imidazolium‐Ringen gebildeten Käfigpaare kann jeweis ein Solvensmolekül S (6: S = CHCl3; 7: S = CH3CN) ohne signifikante Änderung der Atomkoordinaten eingelagert werden. Im Gegensatz zu 5 besteht 8 im festen Zustand aus isolierten Ionen. Die Kristallstrukturen von 5 — 8 werden diskutiert.
On the Reaction of Triaryl Trithioarsenites, (ArS)3As, with Octasulfur
Authors: Haikou Maria N. , Tsivgoulis Gerasimos M. , Ioannou Panayiotis V.
Published: July 2004

para‐Substituted with electron donating or electron withdrawing groups triphenyl trithioarsenites, (ArS)3As, and octasulfur in refluxing carbon disulfide or chloroform do not give the triaryl tetrathioarsenates, (ArS)3As=S, as was claimed in the literature for tris(4‐methylphenyl) tetrathioarsenate. In some cases oxidative decomposition to As2O3 and disulfides ArSSAr was found. When equivalent amounts of the same esters and octasulfur were heated at 105 or 150 °C no AsV compound was detected or isolated and again some esters decomposed to As2O3 and disulfides. These experiments demonstrated that the aromatic trithioarsenites do not react with octasulfur, probably because they cannot open the octasulfur ring. These esters in solution react with octasulfur in the presence of a catalytic (10—20 mol%) amount of triethylamine giving disulfides, As2O3 and colored solids which could not be characterized.
Hg4OF6, das erste Quecksilberoxidfluorid
Authors: Müller Bernd G. , Klein Wilhelm , Jansen Martin
Published: July 2004

Hg4OF6, das erstmals als Produkt der thermischen Zersetzung von (O2)2Hg2F(SbF6)5 in Form eines zinnoberroten, kristallinen Pulvers beobachtet wurde, läßt sich durch Festkörperreaktion aus den binären Komponenten HgO und HgF2 phasenrein darstellen. Es kristallisiert hexagonal im Ba4OCl6‐Typ (P63mc (Nr. 186), a = 774.57(1), c = 600.75(1) pm, Z = 2, Rietveld‐Profilanpassung, RP = 6.17 %, RwP = 8.00 %).
Ca2[BN2]H: The First Nitridoborate Hydride — Synthesis, Crystal Structure, and Vibrational Spectra
Authors: Somer Mehmet , Yaren Özlem , Reckeweg Olaf , Prots Yurii , Carrillo‐Cabrera Wilder
Published: July 2004

Ca2[BN2]H was synthesized from a mixture of the binary components Ca3N2, CaH2 and BN (molar ratio 1 : 1 : 2) in a sealed steel ampoule encapsulated in an evacuated silica tube at 1273 K. Ca2[BN2]H crystallizes in the orthorhombic space group Pnma (no. 62) with a = 9.2015(8)Å, b = 3.6676(2)Å and c = 9.9874(12)Å (Z = 4; Pearson symbol oP24). The crystal structure is a filled variant of the Co2P type and can be formulated as Co2P(□t)3(□py)3 ≡ Ca2[N—B—N]H(□t)2(□py)3 (□t and □py = tetrahedral and square‐pyramidal hole, respectively). The d(B—N) bond lengths and bond angle for the linear [N—B—N]3— anion are: d(B—N1) = 1.324(3)Å, d(B—N2) = 1.350(2)Å and ∠N—B—N = 177.2(2)°. The vibrational spectra of Ca2[BN2]H confirm the presence of [N—B—N]3— groups deviating only slightly from the ideal D∞h symmetry. The vibrational frequencies and the ƒ(B—N) force constants are discussed and compared with those of the isotypic compound Ca2[BN2]F.
Oxidative Dimerisierung von Phosphanen und Hinweise auf das intermediäre Auftreten des Phosphinophosphinidens tBu2P—P in Reaktionen von [(η5‐C5H5)2TiCl2] und [(η5‐C5H5)(η5‐C5Me5)TiCl2] mit tBu2P—P(SiMe3)Li und tBu2P—P(Li)—PtBu2. Bildung von Titan(III)‐Fulvalen‐Komplexen
Authors: Baum Elke , Matern Eberhard , Pikies Jerzy , Robaszkiewicz Andrzej
Published: July 2004

Die Umsetzungen von [Cp2TiCl2] (Cp = C5H5) mit tBu2P—P(Li)—PtBu2 oder mit tBu2P—P(SiMe3)Li führen zur Bildung von TiIII‐Komplexen wie [Cp2Ti{μ‐Cl}2Li(THF)2] (monoklin C2/c) oder [(Cp2Ti{μ‐Cl})2] und in Gegenwart von PMe3 auch zu [Cp2TiCl(PMe3)]. Gleichzeitig dimerisieren die Phosphanreste zu (tBu2P)2P—P(PtBu2)2 bzw. (tBu2P—PSiMe3)2. Zusammen mit (tBu2P—PSiMe3)2 bilden sich Produkte, die auf das intermediäre Auftreten von tBu2P—P hindeuten.

Die Umsetzung von [Cp2TiCl2] bzw. von [Cp(Cp*)TiCl2] (Cp* = C5Me5) mit nBuLi in Gegenwart von tBu2P—P(SiMe3)2 liefert unerwartet die TiIII‐Fulvalen‐Komplexe [{Ti(η5‐C5H5)(μ‐Cl)}2{μ‐(η5‐C5H4‐η5‐C5H4)}] und [{Ti(η5‐C5Me5)(μ‐Cl)}2{μ‐(η5‐C5H4‐η5‐C5H4)}] (triklin, P1¯).
DFT‐Berechnungen an adamantanartigen Phosphoroxid‐sulfiden der allgemeinen Formel P4O10—nSn (n = 1—9)
Authors: Huu Thong Nguyen , Meisel Manfred
Published: July 2004

Die vor einer Reihe von Jahren experimentell bei Reorganisationsreaktionen zwischen P4S10 und P4O10 gefundene Stabilität von Isomeren der Phosphoroxidsulfide der allgemeinen Formel P4O10—nSn wurde durch Dichtefunktionaltheorie(DFT)‐Rechnungen bestätigt. Die erhaltenen Daten lassen auch Aussagen über die Chancen einer erfolgreichen Darstellung bisher noch nicht isolierter oder unzureichend charakterisierter Phosphoroxidsulfid‐Isomere zu.
Chemischer Transport fester Lösungen. 14 [1] Der Chemische Transport von GaP und von Mischphasen im System ZnS/GaP
Authors: Locmelis S. , Binnewies M.
Published: July 2004

Mithilfe chemischer Transportreaktionen (Transportmittel Iod, 1000 → 900 °C) konnten im System ZnS/GaP Mischphasen durch chemischen Transport erhalten werden. Bei 900 °C beträgt die Löslichkeit von ZnS in GaP 7 %, die von GaP in ZnS 10 %. Über den Transport von reinem GaP wird berichtet. Er erfolgt entsprechend der Transportgleichung 2 GaP(s) +GaI3(g) = 2 GaI(g) + 0, 5 P4(g).