Assessing Differences Between Results Determined According to the Guide to the Expression of Uncertainty in Measurement

In some metrology applications multiple results of measurement for a common measurand are obtained and it is necessary to determine whether the results agree with each other. A result of measurement based on the Guide to the Expression of Uncertainty in Measurement (GUM) consists of a measured value together with its associated standard uncertainty. In the GUM, the measured value is regarded as the expected value and the standard uncertainty is regarded as the standard deviation, both known values, of a state-of-knowledge probability distribution. A state-of-knowledge distribution represented by a result need not be completely known. Then how can one assess the differences between the results based on the GUM? Metrologists have for many years used the Birge chisquare test as ‘a rule of thumb’ to assess the differences between two or more measured values for the same measurand by pretending that the standard uncertainties were the standard deviations of the presumed sampling probability distributions from random variation of the measured values. We point out that this is misuse of the standard uncertainties; the Birge test and the concept of statistical consistency motivated by it do not apply to the results of measurement based on the GUM. In 2008, the International Vocabulary of Metrology, third edition (VIM3) introduced the concept of metrological compatibility. We propose that the concept of metrological compatibility be used to assess the differences between results based on the GUM for the same measurand. A test of the metrological compatibility of two results of measurement does not conflict with a pairwise Birge test of the statistical consistency of the corresponding measured values.     

Biocompatible Gas Plasma Treatment Affects Secretion Profiles but Not Osteogenic Differentiation in Patient-Derived Mesenchymal Stromal Cells

Cold physical plasma (CPP), a partially ionized gas that simultaneously generates reactive oxygen and nitrogen species, is suggested to provide advantages in regenerative medicine. Intraoperative CPP therapy targeting pathologies related to diminished bone quality could be promising in orthopedic surgery. Assessment of a clinically approved plasma jet regarding cellular effects on primary bone marrow mesenchymal stromal cells (hBM-MSCs) from relevant arthroplasty patient cohorts is needed to establish CPP-based therapeutic approaches for bone regeneration. Thus, the aim of this study was to derive biocompatible doses of CPP and subsequent evaluation of human primary hBM-MSCs’ osteogenic and immunomodulatory potential. Metabolic activity and cell proliferation were affected in a treatment-time-dependent manner. Morphometric high content imaging analyses revealed a decline in mitochondria and nuclei content and increased cytoskeletal compactness following CPP exposure. Employing a nontoxic exposure regime, investigation on osteogenic differentiation did not enhance osteogenic capacity of hBM-MSCs. Multiplex analysis of major hBM-MSC cytokines, chemokines and growth factors revealed an anti-inflammatory, promatrix-assembling and osteoclast-regulating secretion profile following CPP treatment and osteogenic stimulus. This study can be noted as the first in vitro study addressing the influence of CPP on hBM-MSCs from individual donors of an arthroplasty clientele.     

Complex analysis of SiOxCyHz films deposited by an atmospheric pressure dielectric barrier discharge

SiO_x films are deposited with an atmospheric pressure dielectric barrier discharge (apDBD) using Ar, O₂ and different precursor gases (HMDSO and Silane). An experimental study on the influence of the discharge operation parameters on the chemical composition of the deposited films and the vertical structure over the film thickness is carried out by means of SEM, EDX, and ATR–FTIR. Particularly the IR absorption of hydroxyl groups (OH) incorporated in the films is considered in dependence of the deposition conditions. OH can be regarded as an indicator for the barrier properties of the coating or its capability to transport metal ions through the film. The latter process leads to applications in antimicrobial coatings that gradually, over time release e.g. copper or silver ions under wet conditions. The potential of organosilicon films produced in such an atmospheric pressure PECVD with regard to this application is demonstrated for the first time.     

A chemically driven insulator-metal transition in non-stoichiometric and amorphous gallium oxide

Insulator-metal transitions are well known in transition-metal oxides, but inducing an insulator-metal transition in the oxide of a main group element is a major challenge. Here, we report the observation of an insulator-metal transition, with a conductivity jump of seven orders of magnitude, in highly non-stoichiometric, amorphous gallium oxide of approximate composition GaO(1.2) at a temperature around 670 K. We demonstrate through experimental studies and density-functional-theory calculations that the conductivity jump takes place at a critical gallium concentration and is induced by crystallization of stoichiometric Ga(2)O(3) within the metastable oxide matrix-in chemical terms by a disproportionation. This novel mechanism--an insulator-metal transition driven by a heterogeneous solid-state reaction--opens up a new route to achieve metallic behaviour in oxides that are expected to exist only as classic insulators.     

Managing collaboration performance to govern virtual organizations

The ability to collaborate with partners will become an essential core competence that is required from companies when they are going to take up future challenges. Growing complexity of products and services, increasing global competition and accelerated business processes will exceed in many cases the capabilities and capacities of single companies. The involvement of other companies can help to overcome these limitations. However, only what is measured can be managed. Consequently it is necessary to assess the effectiveness and efficiency of how partners work together in joint processes for a common goal. In other word: the collaboration performance has to be measured. But traditional Performance Measurement (PM) methodologies and indicators are designed to assess the performance of single companies or static cooperation like in supply chains. Evaluation and management of collaboration performance as a particular performance perspective in cooperation is not covered by existing approaches so far. Therefore there is still a need for an approach that provides an information basis for the management of collaboration when companies work together in in cooperation. In this paper, which is initially based on a paper presented on the ProVE conference in 2007, different perspectives of collaboration performance are identified and structured. The considerations are based on Virtual Organisations VOs, a particular type of cooperation that requires usually intensive collaborative interactions between the partners.     

Gold-Catalyzed Glucose Oxidation Using Novel Spherical Sol–Gel Derived Alumina Supports Produced via the JetCutter

Monodisperse ??-Al₂O₃ beads with a diameter of 250???m were prepared via a sol?Cgel method and the JetCutter. The bead-shaped support was used for the preparation of 0.23?% Au/??-Al₂O₃ catalyst beads which were applied in the oxidation of glucose to gluconic acid. Simplified calculations of the effectiveness factor revealed that especially at high glucose concentrations the use of hydrogen peroxide would lead to much a higher catalyst activity than the use of oxygen as oxidant which was confirmed by the experimental results.