Lactobacilli have a niche in the human nose

Although an increasing number of beneficial microbiome members are characterized for the human gut and vagina, beneficial microbes are underexplored for the human upper respiratory tract (URT). In this study, we demonstrate that taxa from the beneficial Lactobacillus genus complex are more prevalent in the healthy URT than in patients with chronic rhinosinusitis (CRS). Several URT-specific isolates are cultured, characterized, and further explored for their genetic and functional properties related to adaptation to the URT. Catalase genes are found in the identified lactobacilli, which is a unique feature within this mostly facultative anaerobic genus. Moreover, one of our isolated strains, Lactobacillus casei AMBR2, contains fimbriae that enable strong adherence to URT epithelium, inhibit the growth and virulence of several URT pathogens, and successfully colonize nasal epithelium of healthy volunteers. This study thus demonstrates that specific lactobacilli are adapted to the URT and could have a beneficial keystone function in this habitat

On the computation of the shadow wage rate in an autarkic agricultural environment

info:eu-repo/semantics/publishe

Defining the Optimal Beam Hardening Correction Parameters for CT Dimensional Metrology Applications

Recently, X-ray CT technology has entered the application field of dimensional metrology, as alternative to tactile and optical 3D coordinate measuring techniques. Nevertheless, the measurement quality of industrial CT machines is affected by many parameters and phenomenon, among which beam hardening plays a crucial role. It has been proven that the accuracy and uncertainty of CT dimensional measurements is largely influenced by the applied beam hardening correction method. As a routine procedure in industry, the beam hardening effect is corrected by applying hardware pre-filtration complemented with a software correction that implies linearization using predefined polynomial fitting curves. This correction method can largely eliminate beam hardening artifacts e.g. cupping effect and streaks. However, measurement results reveal that the effectiveness of such method is closely related to the selected X-ray power and hardware filter. Over-correction often occurs with inappropriate machine settings, which results in dimensional errors. This paper investigates the correlation between X-ray power, filter and beam hardening correction parameters, and aims at establishing a procedure for defining the optimal beam hardening correction parameters for CT dimensional metrology applications.status: publishe

Material Dependent Thresholding for Dimensional X-ray Computed Tomography

Recently, the use of Computed Tomography for dimensional metrology has been emerging as a new application field. This new application domain calls for micron-level accuracy and traceability to the unit of length. Unfortunately, CT images inherently bear many artifacts, such as beam hardening and scattering noise. Moreover, the partial volume effect hinders accurate thresholding, which limits the achievable accuracy of CT dimensional metrology. Until now, the edge detection of single material workpieces in CT imaging commonly relies on the 50% iso-surface global thresholding method. In addition, advanced „local thresholding‟ methods have been developed to reduce some artifacts and to improve CT model surface quality. Yet often, neither method can define the „exact‟ edge, hence resulting in dimensional errors. This paper reports on material dependent thresholding. The position of the edge is shifted along the gray value histogram between the background (air) and material peaks, in order to check which value yields the most accurate dimensions, hence the most correct edge. The influences of material type on the exact edge location in the gray value histogram are presented. Application of this method on different materials has yielded consistent results.status: publishe

A European Academy of Rehabilitation Medicine Academic Debate: Describing Experienced Health on the Basis of the WHO's Model of Functioning (ICF) or on the Theory of Social Productivity

The first Academic Debate was held within the European Academy of Rehabilitation Medicine (EARM) in Budapest in 2016. The question debated was: is it possible to provide a theory neutral framework to describe the lived experience of health or is there an appropriate theory to understand what constitute the most relevant factors in health (and well-being). First the link between the International Classification of Functioning, Disability and Health (ICF) and rehabilitation as a key health strategy was explained. It was then argued that supplementing the ICF by theory-based approaches (e.g. a theory of social productivity) may advance explanations with regard to participation and links with health and well-being. Thirdly, it was recalled that one of the strengths of the ICF is exactly being “theory neutral”. There was no doubt that there is a need for scientific theories to describe functioning and health. The theory of social productivity seems to be an important contribution towards this goal. However, the definition of well-being in relation to the operationalization of functioning and health needs to be further developed. The conclusion cannot be an “either-or” (classification vs theory). Projects should be set up both to further develop the ICF and to refine (or develop new) theories

Parameter dependent thresholding for dimensional X-ray computed tomography

While computed tomography (CT) has since long been used for medical applications and material inspection, its application field has recently been broadened to include dimensional metrology in industry. However, the accuracy and repeatability of CT-based measurements remain yet largely uncertain. Not only are the measurements influenced by a number of factors and parameters like e.g. voltage, current, magnification, object thickness, … but also the calibration method is of major concern (both for scale errors as well as for offset errors). This paper investigates the influence of the power settings (voltage and current) on the accuracy and repeatability of dimensional measurements. Experiments show that after rescaling the pixel size (to compensate for scale errors), the accuracy still remains dependent on the energy used. After correction of the edge threshold value (offset error), measurement results become less dependent on the voltage and current used and are more repeatable. Beam hardening effects cause the material thickness of the measurand to be another important parameter. Using spheres of different sizes, the dependence of the edge offset error on the sphere diameter is investigated.status: publishe

Industrial computer tomography for dimensional metrology: Overview of influence factors and improvement strategies

While Computer Tomography (CT) has since long been used for medical applications and material inspection, its application field has recently been broadened to include dimensional metrology in industry. In particular, it provides a unique means of measuring assemblies, complex structures as well as the inner geometry of parts made by rapid manufacturing in a non-destructive way. However, the accuracy of CT-based measurements remains yet largely uncertain, due to a number of influencing factors related to the workpiece, the CT equipment as well as the measurement setup. This paper first classifies the factors influencing the CT performance on the basis of the basic components of the CT system. Next, the obtained knowledge is used to suggest improvement strategies to ameliorate the accuracy of CT measurements.status: publishe

A test object for calibration and accuracy assessment in X-ray CT metrology

While Computer Tomography (CT) has since long been used for medical applications and material inspection, its application field has recently been broadened to include dimensional metrology in industry. However, the accuracy of CT-based measurements remains yet largely uncertain. Not only are the measurements influenced by a number of factors and parameters like e.g. workpiece orientation, magnification, edge detection... but also the calibration method matters greatly. This paper investigates the influence of these factors and parameters and the calibration method (rescaling and correction) on accuracy and repeatability of the measurements, using a test object with parallel grooves. The test object is also used to illustrate how more accurate CMM measurements can be used to calibrate CT measurements and to compare different calibration and compensation strategies.status: publishe