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This document describes the specification of the Sparsely Coded Residuals (SCR) file format for storing three-dimensional volume data in a compressed form. More precisely, the format is designed to store representations of reconstructed volumes in three-dimensional computed tomography in a wavelet basis. It is flexible with regards to the choice of wavelets, thresholding techniques, and tiling for large datasets. Based on the netCDF container format, SCR contains the structure of the stored information and in this sense, it is a self-describing format. This manuscript provides a report of the main concepts of SCR, and closes with an overview of possible user-defined extensions.

In many applications of X-ray computed tomography, an unsupervised segmentation of the reconstructed 3D volumes forms an important step in the image processing chain for further investigation of the digitized object. Therefore, the goal is to train a clustering algorithm on the volume, which produces a voxelwise classification by assigning a cluster index to each voxel. However, clustering methods, e.g., K-Means, typically have an asymptotic polynomial runtime with respect to the dataset size, and thus, these techniques are rarely applicable to large volumes. In this work, we introduce a novel clustering technique based on random sampling, which allows for the voxelwise classification of arbitrarily large volumes. The presented method conducts efficient linear passes over the data to extract a representative random sample of a fixed size on which the classifier can be trained. Then, a final linear pass performs the segmentation and assigns a cluster index to each individual voxel. Quantitative and qualitative evaluations show that excellent results can be achieved even with a very small sample size. Consequently, the unsupervised segmentation by means of clustering becomes feasible for arbitrarily large volumes., 12 pages, 8 figures

Kunstchronik. Monatsschrift für Kunstwissenschaft, Museumswesen und Denkmalpflege, Bd. 72 Nr. 11 (2019): Kunstchronik. Monatsschrift für Kunstwissenschaft, Museumswesen und Denkmalpflege

Thresholding is the most widely used segmentation method in volumetric image processing, and its pointwise nature makes it attractive for the fast handling of large three-dimensional samples. However, global thresholds often do not properly extract components in the presence of artifacts, measurement noise or grayscale value fluctuations. This paper introduces Feature-Adaptive Interactive Thresholding (FAITH), a thresholding technique that incorporates (geometric) features, local processing and interactive user input to overcome these limitations. Given a global threshold suitable for most regions, FAITH uses interactively selected seed voxels to identify critical regions in which that threshold will be adapted locally on the basis of features computed from local environments around these voxels. The combination of domain expert knowledge and a rigorous mathematical model thus enables a very exible way of local thresholding with intuitive user interaction. A qualitative analysis shows that the proposed model is able to overcome limitations typically occuring in plain thresholding while staying efficient enough to also allow the segmentation of big volumes., Comment: 13 pages, 3 figures, 2 tables

Segmentation, i.e., the partitioning of volumetric data into components, is a crucial task in many image processing applications ever since such data could be generated. Most existing applications nowadays, specifically CNNs, make use of voxelwise classification systems which need to be trained on a large number of annotated training volumes. However, in many practical applications such data sets are seldom available and the generation of annotations is time-consuming and cumbersome. In this paper, we introduce a novel voxelwise segmentation method based on active learning on geometric features. Our method uses interactively provided seed points to train a voxelwise classifier based entirely on local information. The combination of an ad hoc incorporation of domain knowledge and local processing results in a flexible yet efficient segmentation method that is applicable to three-dimensional volumes without size restrictions. We illustrate the potential and flexibility of our approach by applying it to selected computed tomography scans where we perform different segmentation tasks to scans from different domains and of different sizes., Comment: 10 pages, 27 figures, 3 tables

Cigarette smoking increases the likelihood of developing anxiety disorders, among them panic disorder (PD). While brain structures altered by smoking partly overlap with morphological changes identified in PD, the modulating impact of smoking as a potential confounder on structural alterations in PD has not yet been addressed. In total, 143 PD patients (71 smokers) and 178 healthy controls (62 smokers) participated in a multicenter magnetic resonance imaging (MRI) study. T1-weighted images were used to examine brain structural alterations using voxel-based morphometry in a priori defined regions of the defensive system network. PD was associated with gray matter volume reductions in the amygdala and hippocampus. This difference was driven by non-smokers and absent in smoking subjects. Bilateral amygdala volumes were reduced with increasing health burden (neither PD nor smoking > either PD or smoking > both PD and smoking). As smoking can narrow or diminish commonly observed structural abnormalities in PD, the effect of smoking should be considered in MRI studies focusing on patients with pathological forms of fear and anxiety. Future studies are needed to determine if smoking may increase the risk for subsequent psychopathology via brain functional or structural alterations.

Purpose: Automating tasks such as lung tumor localization and segmentation in radiological images can free valuable time for radiologists and other clinical personnel. Convolutional neural networks may be suited for such tasks, but require substantial amounts of labeled data to train. Obtaining labeled data is a challenge, especially in the medical domain. Methods: This paper investigates the use of a teacher-student design to utilize datasets with different types of supervision to train an automatic model performing pulmonary tumor segmentation on computed tomography images. The framework consists of two models: the student that performs end-to-end automatic tumor segmentation and the teacher that supplies the student additional pseudo-annotated data during training. Results: Using only a small proportion of semantically labeled data and a large number of bounding box annotated data, we achieved competitive performance using a teacher-student design. Models trained on larger amounts of semantic annotations did not perform better than those trained on teacher-annotated data. Conclusions: Our results demonstrate the potential of utilizing teacher-student designs to reduce the annotation load, as less supervised annotation schemes may be performed, without any real degradation in segmentation accuracy., 17 pages, 3 figures, 5 tables, submitted to journal

Adaption to changing environments is evolutionarily advantageous. Studies that link genetic and phenotypic expression of flexible adjustment to one's context are largely lacking. In this study, we tested the importance of psychological flexibility, or goal-related context sensitivity, in an interaction between psychotherapy outcome for panic disorder with agoraphobia (PD/AG) and a genetic polymorphism. Given the established role of the 5HTT-LPR polymorphism in behavioral flexibility, we tested whether this polymorphism (short group vs. long group) impacted therapy response as a function of various endophenotypes (i.e., psychological flexibility, panic, agoraphobic avoidance, and anxiety sensitivity). Patients with PD/AG were recruited from a large multicenter randomized controlled clinical trial on cognitive-behavioral therapy. Pre- to post-treatment changes by 5HTT polymorphism were analyzed. 5HTT polymorphism status differentiated pre- to post-treatment changes in the endophenotype psychological flexibility (effect size difference d=0.4, p

PurposePatients with non-Hodgkin lymphoma (NHL) have a median age of 67, with 70% surviving over 5 years. Chemotherapy for aggressive NHL includes cyclophosphamide, anthracycline, and high doses of corticosteroids, which can impair bone health. By reviewing clinical characteristics and standard-of-care CT scans, we evaluate the prevalence and incidence of fractures and the clinical correlates of fractures in patients treated for aggressive B-cell NHL.MethodsWe retrospectively reviewed patients seen at the University of California San Francisco lymphoma clinic from January 1, 2016, to March 31, 2017 who had (1) aggressive B-cell NHL, (2) received first-line therapy with R-CHOP-like regimens, and had (3) CT scans pre- and post-treatment available for review. Associations between clinical variables and vertebral, rib, and pelvic fracture outcomes were assessed, and multivariate logistic regression models were used to identify predictors of prevalent and incident fractures.ResultsWe identified 162 patients who met the inclusion criteria. Median age at diagnosis was 60 years. Of the 162 patients, 38 patients (28%) had prevalent fractures prior to receiving chemotherapy. Within 1 year after treatment, 16 patients (10%) developed new fractures. Having a prevalent fracture strongly predicted developing a new fracture after treatment, with incident fractures occurring in 12 of 38 patients with prevalent fractures versus 4 of 124 without prevalent fractures (odds ratio 10.45, p

The segmentation of volumetric datasets, i.e., the partitioning of the data into disjoint sub-volumes with the goal to extract information about these regions,is a difficult problem and has been discussed in medical imaging for decades. Due to the ever-increasing imaging capabilities, in particular in X-ray computed tomography (CT) or magnetic resonance imaging, segmentation in industrial applications also gains interest. Especially in industrial applications the generated datasets increase in size. Hence, most applications apply well-known techniques in a 2+1-dimensional manner,i.e., they apply image segmentation procedures on each slice separately and track the progress along the axis of the volume in which the slices are stacked on. This discards the information on preceding or subsequent slices, which is often assumed to be nearly identical. However, in the industrial context this might prove wrong since industrial parts might change their appearance significantly over the course of even a few slices. Moreover, artifacts can further distort the content of the slices. Therefore, three-dimensional processing of voxel volumes has to be preferred, which induces constraints upon the segmentation procedures. For example, they must not consider global information as it is usually not feasible in big scans to compute them efficiently. Yet another frequent problem is that applications focus on individual parts only and algorithms are tailored to that case. Most prominent medical segmentation procedures do so by applying methods to specifically find the liver and only the liver of a patient, for example. The implication is that the same method then cannot be applied to find other parts of the scan and such methods have to be designed individually for any object to be segmented. Flexible segmentation methods are needed too specifically when partitioning unique scans. We define a unique scan to be a voxel dataset for which no comparable volume exists. Classical examples include the use case of cultural heritage where not only the objects themselves are unique but also scan parameters are optimized to obtain the best image quality possible for that specific scan. This thesis aims at introducing novel methods for voxelwise classifications based on local geometric features. The latter are computed from local environments around each voxel and extract information in similar ways as humans do, namely by observing their similarity to geometric or textural primitives. These features serve as the foundation to learning the proposed voxelwise classifiers and to discriminate between segmented and unsegmented voxels. On the one hand, they perform fully automated clustering of volumes for which a representative random sample is extracted first. On the other hand, a set of segmenting classifiers can be trained from few seed voxels, i.e., volume elements for which a domain expert marked if they belong to the components that shall be segmented. The interactive selection offers the advantage that no completely labeled voxel volumes are necessary and hence that unique scans of objects can be segmented for which no comparable scans exist. Overall, it will be shown that all proposed segmentation methods are effectively of linear runtime with respect to the number of voxels in the volume. Thus, voxel volumes without size restrictions can be segmented in an efficient linear pass through the volume. Finally, the segmentation performance is evaluated on selected datasets which shows that the introduced methods can achieve good results on scans from a broad variety of domains for both small and big voxel volumes. Die Segmentierung von Volumendaten, also die Partitionierung der Daten in disjunkte Teilvolumen zur weiteren Informationsextraktion, ist ein Problem, welches in der medizinischen Bildverarbeitung seit Jahrzehnten behandelt wird. Bedingt durch die sich ständig verbessernden Bilderfassungsmethoden, speziell im Bereich der Röntgen-Computertomographie (CT) oder der Magnetresonanztomographie, gewinnt die Segmentierung von industriellen Volumendaten auch an Wichtigkeit. Insbesondere im industriellen Kontext steigt die Größe der zu segmentierenden Daten jedoch rasant an, so dass sich die meisten Segmentierungsapplikationen auf den 2+1-dimensionalen Fall beschränken, also Bilder verarbeiten und die Ergebnisse über mehrere Bilder hinweg verfolgen. Jedoch werden somit beispielsweise geometrische Informationen über benachbarte Schichten ignoriert. Diese können sich aber gerade im industriellen Bereich signifikant ändern. Aus diesem Grund ist hier die dreidimensionale Bildverarbeitung vorzuziehen. Dadurch ergeben sich neue Einschränkungen, beispielsweise können keine globalen Informationen zur Segmentierung herangezogen werden, da diese typischerweise nicht effizient berechenbar sind. Ferner fokussieren sich dreidimensionale Methoden aus medizinischen Bereichen zumeist auf bestimmte Bestandteile der Daten, wie einzelne Organe. Dies schränkt die Generalität dieser Methoden signifikant ein und somit sind separate Verfahren für jedes zu segmentierende Objekt notwendig. Flexible Methoden sind darüber hinaus bei Anwendung auf einzigartige Scans erforderlich. Ein einzigartiger Scan ist ein Voxelvolumen, für welches kein vergleichbares Datum existiert. Klassische Beispiele sind Kulturgutdigitalisate, da dort nicht nur die Objekte einzigartig sind, sondern auch die Aufnahmeparameter spezifisch für diesen einen Scan optimiert wurden. Die vorliegende Dissertation führt neuartige Methoden zur voxelweisen dreidimensionalen Segmentierung von Volumendaten auf Basis lokaler geometrischer Informationen ein. Die Bewertung dieser Informationen imitiert die menschliche Objektwahrnehmung, indem lokale Regionen mit geometrischen oder strukturellen Primitiven verglichen werden. Mit Hilfe dieser Bewertungen werden voxelweise anzuwendende Klassifikatoren trainiert, welche zwischen erwünschten und unerwünschten Voxeln unterscheiden sollen. Ein Teil dieser Klassifikatoren führt eine vollautomatische Clustering-Analyse durch, nachdem eine repräsentative und zufällig ausgewählte Teilmenge fester Größe an Voxeln selektiert wurde. Die verbliebenen Segmentierungsalgorithmen erhalten Trainingsdaten in Form von Seed-Voxeln, also wenige Volumenelemente, die von einem Domänenexperten markiert wurden. Diese interaktive Herangehensweise ermöglicht das Einbringen von Expertenwissen ohne die Notwendigkeit vollständig annotierter Trainingsvolumen, wodurch auch einzigartige Scans segmentiert werden können. Für alle Verfahren wird dargelegt, dass die eingeführten Algorithmen von asymptotisch linearer Laufzeit in der Anzahl der Voxel im Volumen sind. Somit können Voxeldaten ohne Größenbeschränkungen in einem effizienten linearen Durchgang verarbeitet werden. Abschließend wird die Performanz der vorgestellten Verfahren auf ausgewählten Daten evaluiert und aufgezeigt, dass mit denselben wenigen Verfahren gute Ergebnisse auf vielen unterschiedlichen Domänen und gleichfalls auf kleinen und großen Volumen erzielt werden können.

Ohne Daten keine Kreislaufivirtschaft : Zirkuläres Bauen funktioniert nur, wenn strukturierte lnformationen über Materialien und Bauteile mittels BIM erfasst werden.

Quantum simulation using synthetic systems is a promising route to solve outstanding quantum many-body problems in regimes where other approaches, including numerical ones, fail. Many platforms are being developed towards this goal, in particular based on trapped ions, superconducting circuits, neutral atoms or molecules. All of which face two key challenges: (i) scaling up the ensemble size, whilst retaining high quality control over the parameters and (ii) certifying the outputs for these large systems. Here, we use programmable arrays of individual atoms trapped in optical tweezers, with interactions controlled by laser-excitation to Rydberg states to implement an iconic many-body problem, the antiferromagnetic 2D transverse field Ising model. We push this platform to an unprecedented regime with up to 196 atoms manipulated with high fidelity. We probe the antiferromagnetic order by dynamically tuning the parameters of the Hamiltonian. We illustrate the versatility of our platform by exploring various system sizes on two qualitatively different geometries, square and triangular arrays. We obtain good agreement with numerical calculations up to a computationally feasible size (around 100 particles). This work demonstrates that our platform can be readily used to address open questions in many-body physics., Main text: 6 pages, 4 figures. Supplementary information: 10 pages, 16 figures

Cigarette smoking increases the likelihood of developing anxiety disorders, among them panic disorder (PD). While brain structures altered by smoking partly overlap with morphological changes identified in PD, the modulating impact of smoking as a potential confounder on structural alterations in PD has not yet been addressed. In total, 143 PD patients (71 smokers) and 178 healthy controls (62 smokers) participated in a multicenter magnetic resonance imaging (MRI) study. T1-weighted images were used to examine brain structural alterations using voxel-based morphometry in a priori defined regions of the defensive system network. PD was associated with gray matter volume reductions in the amygdala and hippocampus. This difference was driven by non-smokers and absent in smoking subjects. Bilateral amygdala volumes were reduced with increasing health burden (neither PD nor smoking > either PD or smoking > both PD and smoking). As smoking can narrow or diminish commonly observed structural abnormalities in PD, the effect of smoking should be considered in MRI studies focusing on patients with pathological forms of fear and anxiety. Future studies are needed to determine if smoking may increase the risk for subsequent psychopathology via brain functional or structural alterations.

Background: Under the new psychotherapy law in Germany, standardized patients (SPs) are to become a standard component inpsychotherapy training, even though little is known about their authenticity.Objective:The present pilot study explored whether, followingan exhaustive two-day SP training, psychotherapy trainees can distinguish SPs from real patients. Methods: Twenty-eight psychotherapytrainees (M= 28.54 years of age,SD= 3.19) participated as blind raters. They evaluated six video-recorded therapy segments of trained SPsand real patients using the Authenticity of Patient Demonstrations Scale. Results: The authenticity scores of real patients and SPs did notdiffer (p= .43). The descriptive results indicated that the highest score of authenticity was given to an SP. Further, the real patients did notdiffer significantly from the SPs concerning perceived impairment (p= .33) and the likelihood of being a real patient (p= .52). Conclusions: The current results suggest that psychotherapy trainees were unable to distinguish the SPs from real patients. We therefore stronglyrecommend incorporating training SPs before application. Limitations and future research directions are discussed. Theoretischer Hintergrund: Mit dem neu eingeführten Direktstudium für zukünftige Psychotherapeut_innen (PiA) wirdder Einsatz von standardisierten Patient_innen (SP) in der Lehre zunehmen, obwohl die Authentizität der Rollendarstellungen durch SPempirisch bislang kaum untersucht wurde. Ziel der vorliegenden Studie war es daher zu untersuchen, ob SP trainiert werden können, dassPsychotherapeut_innen in Ausbildung (PiA) SP von realen Patient_innen nicht unterscheiden können. Methode: Insgesamt nahmen 28 PiA(M= 28.54 Jahre,SD= 3.19) als verblindete Rater teil. Sie haben sechs Therapiesitzungen von trainierten SP und realen Patient_innen mitder Skala Authentizität von Patientendarstellungen bewertet. Ergebnisse: Die Authentizitätswerte von SP unterschieden sich nicht signifi-kant von realen Patient_innen (p= .43). Deskriptive Ergebnisse legen nahe, dass ein SP im Schnitt am authentischsten bewertet wurde.Darüber hinaus unterschieden sich SP und reale Patient_innen nicht hinsichtlich der wahrgenommenen Beeinträchtigung (p= .33) sowie derWahrscheinlichkeit, als reale/r Patient_in bewertet zu werden (p= .52). Fazit: Die vorliegenden Ergebnisse legen nahe, dass PiA SP vonrealen Patient_innen nicht unterscheiden konnten. Daher legen wir ein ausführliches Training der SP nahe, bevor sie für Studium und Lehreeingesetzt werden. Die Limitationen sowie zukünftige Forschungsideen werden diskutiert.

IntroductionIn addition to well-established links with cardiovascular and respiratory diseases, cigarette smoking may affect skeletal muscle; however, associations with quadriceps atrophy, density, and function are unknown. This study explored the associations of current and former smoking with quadriceps muscle area and attenuation as well as muscle force (assessed as knee extension peak torque) and rate of torque development-a measure of muscle power in older adults.MethodsData from 4469 older adults, aged 66-95 years at baseline in the Age, Gene/Environment Susceptibility-Reykjavik Study with measurements of thigh computed tomography, isometric knee extension testing, self-reported smoking history, and potential covariates were analyzed.ResultsSex differences were observed in these data; therefore, our final analyses are stratified by sex. In men, both former smokers and current smokers had lower muscle area (with β= -0.10, 95% confidence interval [CI] = -0.17 to -0.03 and β = -0.19, 95% CI = -0.33 to -0.05, respectively) and lower muscle attenuation (ie, higher fat infiltration, β = -0.08, 95% CI = -0.16 to -0.01 and β = -0.17, 95% CI = -0.34 to -0.01, respectively) when compared with never smokers. Smoking status was not associated with male peak torque or rate of torque development. In women, current smoking was associated with lower muscle attenuation (β = -0.24, 95% CI = -0.34 to -0.13) compared to never smoking. Among female smokers (current and former), muscle attenuation and peak torque were lower with increasing pack-years.ConclusionsResults suggest that cigarette smoking is related to multiple muscle properties at older age and that these relationships may be different among men and women.ImplicationsThis article presents novel data, as it examined for the first time the relationship between smoking and computed tomography-derived quadriceps muscle size (cross-sectional area) and attenuation. This study suggests that current cigarette smoking is related to higher muscle fat infiltration, which may have significant health implications for the older population, because of its known association with poor physical function, falls, and hip fractures.

Physical activity (PA) enhances proximal femur bone mass, as assessed using projectional imaging techniques. However, these techniques average data over large volumes, obscuring spatially heterogeneous adaptations. The current study used quantitative computed tomography, statistical parameter mapping, and subject-specific finite element (FE) modeling to explore spatial adaptation of the proximal femur to PA. In particular, we were interested in adaptation occurring at the superior femoral neck and improving strength under loading from a fall onto the greater trochanter. High/long jump athletes (n = 16) and baseball pitchers (n = 16) were utilized as within-subject controlled models as they preferentially load their take-off leg and leg contralateral to their throwing arm, respectively. Controls (n = 15) were included but did not show any dominant-to-nondominant (D-to-ND) leg differences. Jumping athletes showed some D-to-ND leg differences but less than pitchers. Pitchers had 5.8% (95% confidence interval [CI] 3.9%-7.6%) D-to-ND leg differences in total hip volumetric bone mineral density (vBMD), with increased vBMD in the cortical compartment of the femoral neck and trochanteric cortical and trabecular compartments. Voxel-based morphometry analyses and cortical bone mapping showed pitchers had D-to-ND leg differences within the regions of the primary compressive trabeculae, inferior femoral neck, and greater trochanter but not the superior femoral neck. FE modeling revealed pitchers had 4.1% (95% CI 1.4%-6.7%) D-to-ND leg differences in ultimate strength under single-leg stance loading but no differences in ultimate strength to a fall onto the greater trochanter. These data indicate the asymmetrical loading associated with baseball pitching induces proximal femur adaptation in regions associated with weight bearing and muscle contractile forces and increases strength under single-leg stance loading. However, there were no benefits evident at the superior femoral neck and no measurable improvement in ultimate strength to common injurious loading during aging (ie, fall onto the greater trochanter), raising questions as to how to better target these variables with PA. © 2019 American Society for Bone and Mineral Research.

Bone marrow adiposity (BMA) is associated with aging and osteoporosis, but whether BMA can predict bone loss and fractures remains unknown. Using data from the Age Gene/Environment Susceptibility (AGES)-Reykjavik study, we investigated the associations between 1 H-MRS-based measures of vertebral bone marrow adipose tissue (BMAT), annualized change in bone density/strength by quantitative computed tomography (QCT) and DXA, and secondarily, with incident clinical fractures and radiographic vertebral fractures among older adults. The associations between BMAT and annualized change in bone density/strength were evaluated using linear regression models, adjusted for age, body mass index (BMI), diabetes, estradiol, and testosterone. Cox proportional hazards models were used to evaluate the associations between baseline BMAT and incident clinical fractures, and logistic regression models for incident vertebral fractures. At baseline, mean ± SD age was 80.9 ± 4.2 and 82.6 ± 4.2 years in women (n = 148) and men (n = 150), respectively. Mean baseline BMAT was 55.4% ± 8.1% in women and 54.1% ± 8.2% in men. Incident clinical fractures occurred in 7.4% of women over 2.8 years and in 6.0% of men over 2.2 years. Incident vertebral fractures occurred in 12% of women over 3.3 years and in 17% of men over 2.7 years. Each 1 SD increase in baseline BMAT was associated with a 3.9 mg2 /cm4 /year greater loss of spine compressive strength index (p value = .003), a 0.9 mg/cm3 /year greater loss of spine trabecular BMD (p value = .02), and a 1.2 mg/cm3 /year greater loss of femoral neck trabecular BMD (p value = .02) in women. Among men, there were no associations between BMAT and changes in bone density/strength. There were no associations between BMAT and incident fractures in women or men. In conclusion, we found greater BMAT is associated with greater loss of trabecular bone at the spine and femoral neck, and greater loss of spine compressive strength, in older women. © 2019 American Society for Bone and Mineral Research.

In Österreich ertranken in den Jahren 2014 bis 2019 jeweils zwischen 25 und 40 Personen. In der Altersgruppe der 0- bis 14-Jährigen stellt Ertrinken eine der häufigsten Todesursachen dar. Etwa ein Drittel aller Ertrinkungsunfälle von Kindern ereignet sich in öffentlichen Badeanstalten, rund ein Viertel im eigenen Gartenpool oder sehr selten in dem des Nachbarn. Jährlich werden rund 4000 Personen bei Badeunfällen verletzt. Der Fokus dieser Arbeit liegt auf den Betreibern von Badeanstalten, deren Gehilfen sowie den Herstellern von für Badeanstalten typischen Anlagen und Geräten. Im ersten Teil der Arbeit wird die vertragliche Beziehung zwischen dem Betreiber der Badeanstalt und dem Badegast erörtert. Insb wird dabei untersucht, ob es sich beim Abschluss eines Badebesuchsvertrages um ein Verbrauchergeschäft iSd § 1 KSchG handelt und inwieweit Haftungsfreizeichnungsklauseln des Badbetreibers zulässig sind. Der zweite Teil der Arbeit beschäftigt sich mit der Haftung des Badbetreibers für eigenes und fremdes Verhalten. Insb werden dabei seine umfangreichen Pflichten beleuchtet. Neben gesetzlichen Vorgaben und den sich aus dem Badebesuchsvertrag ergebenden Pflichten kommt auch den deliktischen Verkehrssicherungspflichten große Bedeutung zu. Eine wichtige Rolle bei der Konkretisierung von Verkehrssicherungspflichten spielen die sog ÖNORMEN. Deren Rechtsnatur wird genauer analysiert. Anhand der einschlägigen Judikatur werden die für eine Badeanstalt typischen Gefahrenquellen ermittelt. Außerdem wird untersucht, welche Sicherheitsvorkehrungen der Betreiber zu treffen hat. Im letzten Teil der Arbeit wird die Haftung des Herstellers von Anlagen und Geräten beleuchtet. Einerseits besteht die Möglichkeit einer verschuldensunabhängigen Haftung des Herstellers nach dem PHG. Andererseits kann dieser auch wegen der Verletzung der Produktbeobachtungspflicht aus Verschulden haften. From 2014 to 2019, between 25 and 40 people per year drowned in Austria. From birth up to the age of 14 years, drowning is one of the most common causes of death of children. Around one third of all drowning accidents of children occur in public swimming pools, around one quarter in their own garden pool or, very rarely, in that of their neighbor. Every year, around 4000 people are injured in swimming accidents. This thesis focuses on the operators of swimming baths and pools, their assistants and the manufacturers of equipment typically found at swimming baths and pools. The first part of the thesis discusses the contractual relationship between the operator of the swimming pool and the visitor. In particular, it examines whether the visitor contract is a consumer contract within the meaning of § 1 KSchG and to what extent clauses exempting the operator from liability are permitted by law. The second part of the thesis deals with the liability of the operator for his/her own as well as third party conduct, particularly his extensive obligations are closely examined. In addition to legal requirements and the obligations arising from the visitor contract, also the safety obligations regarding the duty of care are of great importance. The so-called ÖNORMEN have an important impact on the specification of safety obligations regarding the duty of care. Their legal nature is analysed in detail. The sources of danger typical for a swimming pool are identified on the basis of relevant case law. Furthermore, the safety precautions to be taken by the operator are examined. In the last part of the thesis, the liability of the manufacturer of equipment will be examined. On the one hand, there is the possibility of strict liability of the manufacturer under the PHG. On the other hand, the manufacturer can also be liable for the violation of the product monitoring obligation by negligence. Arbeit an der Bibliothek noch nicht eingelangt - Daten nicht geprüft Abweichender Titel laut Übersetzung des Verfassers/der Verfasserin Karl-Franzens-Universität Graz, Diplomarbeit, 2020 (VLID)5657462

ContextBariatric surgery results in reduced muscle mass as weight is lost, but postoperative changes in muscle strength and performance are incompletely understood.ObjectiveTo examine changes in body composition, strength, physical activity, and physical performance following Roux-en-Y gastric bypass (RYGB).Design, participants, outcomesIn a prospective cohort of 47 adults (37 women, 10 men) aged 45 ± 12 years (mean ± SD) with body mass index (BMI) 44 ± 8 kg/m2, we measured body composition by dual-energy X-ray absorptiometry, handgrip strength, physical activity, and physical performance (chair stand time, gait speed, 400-m walk time) before and 6 and 12 months after RYGB. Relative strength was calculated as absolute handgrip strength/BMI and as absolute strength/appendicular lean mass (ALM).ResultsParticipants experienced substantial 12-month decreases in weight (-37 ± 10 kg or 30% ± 7%), fat mass (-48% ± 12%), and total lean mass (-13% ± 6%). Mean absolute strength declined by 9% ± 17% (P < 0.01). In contrast, relative strength increased by 32% ± 25% (strength/BMI) and 9% ± 20% (strength/ALM) (P < 0.01 for both). There were clinically significant postoperative improvements in all physical performance measures, including mean improvement in gait speed of >0.1 m/s (P < 0.01) and decrease in 400-m walk time of nearly a full minute.ConclusionsIn the setting of dramatic weight loss, lean mass and absolute grip strength declined after RYGB. However, relative muscle strength and physical function improved meaningfully and are thus noteworthy positive outcomes of gastric bypass.

Severe burns are debilitating, life threatening and costly. They are associated with widespread inflammation, insidious coagulopathy, large fluid shifts and variable wound healing. Protein C is a naturally occurring enzyme that circulates in plasma. It plays a central role in inflammation, coagulation, vascular permeability and wound healing. The main aim of this thesis is to outline the scarcely explored relationship between plasma protein C levels and severe burns. Chapter 1 describes the epidemiology and pathophysiology of severe burns, and the function of the protein C system and its relevance to burns. Chapter 2 is the first version of a manuscript subsequently published in Advances in Wound Care. It outlines the assessment and acute management of patients with severe burns. Prominent issues include the potential utility of a variety of biomarkers of burn severity including plasma protein C, the potential superiority of natural colloid solutions over crystalloid solutions in the initial fluid resuscitation phase of management and recent research findings on the operative and perioperative management of patients with severe burns. Emerging methods to facilitate wound healing are described and future research directions are suggested. Chapter 3 is the first version of a manuscript subsequently published in Burns. It describes the major findings of an observational study of patients with severe burns. Key findings include the observation that patients who sustain a severe burn have low levels of plasma protein C and that the protein C level is directly associated with better clinical outcomes. An argument is made that protein C is a potential biomarker of burn severity. Chapter 4 is a general discussion of the potential role of protein C in patients with severe burns, followed by a discussion of pertinent issues with the clinical study described in chapter 3, along with implications for patient management and future research.

BackgroundLean body mass (LM) plays an important role in mobility and metabolic function. We previously identified five loci associated with LM adjusted for fat mass in kilograms. Such an adjustment may reduce the power to identify genetic signals having an association with both lean mass and fat mass.ObjectivesTo determine the impact of different fat mass adjustments on genetic architecture of LM and identify additional LM loci.MethodsWe performed genome-wide association analyses for whole-body LM (20 cohorts of European ancestry with n=38,292) measured using dual-energy X-ray absorptiometry) or bioelectrical impedance analysis, adjusted for sex, age, age2, and height with or without fat mass adjustments (Model 1 no fat adjustment; Model 2 adjustment for fat mass as a percentage of body mass; Model 3 adjustment for fat mass in kilograms).ResultsSeven single-nucleotide polymorphisms (SNPs) in separate loci, including one novel LM locus (TNRC6B), were successfully replicated in an additional 47,227 individuals from 29 cohorts. Based on the strengths of the associations in Model 1 vs Model 3, we divided the LM loci into those with an effect on both lean mass and fat mass in the same direction and refer to those as "sumo wrestler" loci (FTO and MC4R). In contrast, loci with an impact specifically on LM were termed "body builder" loci (VCAN and ADAMTSL3). Using existing available genome-wide association study databases, LM increasing alleles of SNPs in sumo wrestler loci were associated with an adverse metabolic profile, whereas LM increasing alleles of SNPs in "body builder" loci were associated with metabolic protection.ConclusionsIn conclusion, we identified one novel LM locus (TNRC6B). Our results suggest that a genetically determined increase in lean mass might exert either harmful or protective effects on metabolic traits, depending on its relation to fat mass.

Bone marrow adiposity is associated with aging, osteoporosis, and reduced hematopoiesis, as well as anorexia nervosa, but little is known about the underlying mechanisms that affect marrow adiposity. Chronic kidney disease (CKD) may influence bone marrow adipose tissue (BMAT), possibly through loss of lean mass or higher circulating levels of sclerostin. To test these hypotheses, we investigated the cross-sectional association between estimated glomerular filtration rate (eGFR) as a measure of kidney function and 1 H-MRS-based measurement of vertebral BMAT (L1 to L4) in 475 older adults from the Age Gene/Environment Susceptibility (AGES)-Reykjavik study. Mean BMAT was compared in those with eGFR >60 (n = 297) versus those with eGFR 45 to 60 (n = 120) or eGFR 60 (adjusted mean 53.8%; 95% CI, 52.8 to 54.8) (p = 0.0002). BMAT did not differ in those with eGFR 45 to 60 (adjusted mean 54.3%; 95% CI, 52.8 to 55.9) compared with those with eGFR >60 (p = 0.58). In a subgroup of participants with serum sclerostin available (n = 253), additional adjustment for sclerostin attenuated the difference in adjusted mean vertebral BMAT between those with eGFR 60 from 3.7% (p = 0.04) to 2.4% (p = 0.20). CKD stage 3b or worse was associated with greater bone marrow adiposity; this association may be partially mediated by sclerostin. © 2018 American Society for Bone and Mineral Research.

Proceedings of the OAGM Workshop 2018

Obwohl moderne Zeitungen digital erstellt werden, sind explizite Informationen ��ber ihr Layout oft nicht vorhanden, wenn sie nicht getrennt abgespeichert und mit ver��ffentlicht werden. Die Beschaffenheit des Layouts kann, je nach Dateiformat, aus dem digital gespeicherten Inhalt des Dokuments rekonstruiert oder aus dem Dokumentenbild erschlossen werden. Die vorliegende Arbeit stellt eine einfache Methode vor, um rechteckige Regionsgrenzen vom Typ Text oder Bild, die aus Zeitungen und anderen Dokumenten im PDF-Format extrahiert werden k��nnen, zu benutzen, um korrekte und nach Typ klassifizierte Regionsbeschreibungen zu erhalten. Notwendig ist dies, da der Inhalt von PDF-Dokumenten nur nach Text- und Bildkomponenten unterschieden werden kann, und dabei vor allem beim Auslesen der Bilder wegen Schnittmasken je nach angewandter Methode Fehler entstehen k��nnen, wodurch die resultierenden Regionsgrenzen nicht mehr mit den Grenzen der sichtbaren Bilder im Dokument ��bereinstimmen. Daher werden die extrahierten Regionsgrenzen, welche sich ��berlappen oder zu gro�� sein k��nnen, in Kombination mit dem Dokumentenbild benutzt, um sie an die tats��chlichen inhaltlichen Komponenten des Dokuments anzupassen. Um die Regionen anschlie��end klassifizieren zu k��nnen, wird ein auf HOG Features basierender Random Forest Klassifikator an einem manuell annotierten Datensatz trainiert. F��r die Klassifizierung zwischen Text- und Tabellenregionen wird dabei eine error rate von 0.05 und f��r die Unterscheidung zwischen Bild- und Diagrammregionen eine von 0.1 erzielt. Die Segmentierung, welche nur die extrahierten Bild-Regionen betrifft, wird zuerst nach dem Ma�� der fl��chenm����igen ��berlappung zwischen annotierten und segmentierten Regionen evaluiert, womit ein Recall und eine Precision von 0.77 und 0.94 erzielt werden. Zus��tzlich wird sie danach evaluiert, wie viele segmentierte bzw. annotierte Regionen genau (mit einer variablen Toleranz) einer oder mehreren annotierten Regionen aus dem jeweils anderen Datensatz entsprechen. Je nach Toleranz ergeben sich dabei F1-Werte zwischen 0.37 und 0.45, wobei sich herausstellt, dass die Segmentierung bei Diagrammregionen wesentlich ��fter scheitert als bei Bildern. Die Evaluierung des Gesamtsystems wird erneut doppelt vollzogen: nach ��berlappungsfl��che und nach der Anzahl sich entsprechender Regionen. Auch dabei schneiden bei der fl��chenbasierten Evaluierung Diagrammregionen mit einem F1-Wert von 0.21 deutlich schlechter ab als die Regionen der anderen Klassen. Schlie��lich wird die Methode noch mit Tesseract hinsichtlich der Segmentierung und Klassifizierung von Text-, Bild- und Tabellenregionen verglichen. Dabei erzielt die vorgestellte Methode hinsichtlich aller Klassen einen h��heren F1-Score., Even though modern newspapers are born digitally, layout information is often not available if it is not stored separately and distributed alongside them. Depending on the data format, the layout structure can either be reconstructed from the content stored in the digital file or from the document image. This work proposes a method for using rectangular region bounding boxes, which can be extracted from PDF documents, in order to obtain correctly segmented and classified region descriptions. This is necessary because the content extracted from PDF files can only be distinguished as being of the text or image type, and because of clipping masks for image components, the resulting boundaries may not match the visible images in the documents, depending on the extraction method. Therefore, the resulting region boundaries, which may be too large or overlapping, are used in combination with the document image to fit them to the visible component boundaries. In order to classify the regions afterwards, a random forest classifier is trained on a manually annotated dataset using HOG features. The resulting error rates are 0.05 for the distinction between text and table regions, and 0.1 for the classification between image and chart regions. The segmentation, which is only performed on the extracted image regions, is first measured according to the amounts of area overlap between annotated and segmented regions, resulting in a recall value of 0.77 and a precision of 0.94. The second kind of segmentation evaluation consists of counting how many regions of one dataset (segmented or ground-truth) fit a region of the respective other dataset, according to a variable tolerance value. Depending on this value, the resulting F1 scores lie between 0.37 and 0.45. This evaluation also reveals that the segmentation fails significantly more often for chart regions than for images. Both measurements, region overlap and fitting region counts, are again used in the evaluation of the complete system, which shows once more that chart regions are segmented significantly worse than other classes with an overall area-based F1 score of 0.21. The last measurement is a comparison of the proposed technique to Tesseract in terms of segmentation and classification of text, image and table regions, where the proposed system performs better in terms of F1 scores for all classes.

Clinicians frequently treat patients suffering from more than one mental disorder. As they have to choose which disorder to treat first, knowledge on generalization effects or even comorbidity-associated obstacles should guide the clinician’s decision. Patients with panic disorder (PD) and agoraphobia (AG) often suffer from other mental disorders, e.g. social anxiety disorder (SAD) [1]. Nevertheless, evidence is missing whether cognitive-behavioral therapy (CBT) for PD/AG generalizes to SAD or whether comorbid SAD impedes the treatment of primary PD/AG.

The previously published version of this Article contained typographical errors in the spelling of the author names Stephen C. J. Parker and H.-Erich Wichmann, which were incorrectly given as Stephan Parker and H.-Erich Wichman, respectively. Furthermore, Affiliation 53 was incorrectly given as 'Research Group on Geriatrics, The Berlin Aging Study II, ChariteUniversitätsmedizin Berlin, Berlin 13353, Germany', Affiliation 66 was incorrectly given as 'Department of Botany & Plant Sciences, Institute for Integrative Genome Biology, University of California, Riverside, CA 92521, USA', and Affiliation 152 was incorrectly given as 'Group Health Research Institute, Group Health Cooperative, Seattle, WA 98101, USA'. These errors have been corrected in the PDF and HTML versions of the Article.

A correction to this article has been published and is linked from the HTML version of this article.

Objective This study examined associations of regional fat depots with all-cause mortality over 11 years of follow-up. Design and Methods Data were from 2187 men and 2900 women, aged 66–96 years in AGES-Reykjavik Study. Abdominal visceral fat and subcutaneous fat, and thigh intermuscular fat and subcutaneous fat were measured by CT. Results In men, every standard deviation (SD) increment in thigh intermuscular fat was related to a significantly greater mortality risk (HR:1.17, 95%CI:1.08–1.26) after adjustment for age, education, smoking, physical activity, alcohol, BMI, type 2 diabetes and coronary heart disease. In women, visceral fat (per SD increment) significantly increased mortality risk (HR:1.13, 95%CI:1.03–1.25) while abdominal subcutaneous fat (per SD increment) was associated with a lower mortality risk (HR:0.70; 95%CI:0.61–0.80). Significant interactions with BMI were found in women indicating that visceral fat was a strong predictor of mortality in obese women while abdominal and thigh subcutaneous fat were associated with a lower mortality risk in normal and overweight women. Conclusions Fat distribution is associated with mortality over 11 years of follow-up independent of overall fatness. The divergent mortality risks for visceral fat and subcutaneous fat in women suggest complex relationships between overall fatness and mortality.

There is little knowledge about the spatial distribution differences in volumetric bone mineral density and cortical bone structure at the proximal femur between femoral neck fractures and trochanteric fractures. In this case-control study, a total of 93 women with fragility hip fractures, 72 with femoral neck fractures (mean ± SD age: 70.6 ± 12.7 years) and 21 with trochanteric fractures (75.6 ± 9.3 years), and 50 control subjects (63.7 ± 7.0 years) were included for the comparisons. Differences in the spatial distributions of volumetric bone mineral density, cortical bone thickness, cortical volumetric bone mineral density, and volumetric bone mineral density in a layer adjacent to the endosteal surface were investigated using voxel-based morphometry (VBM) and surface-based statistical parametric mapping (SPM). We compared these spatial distributions between controls and both types of fracture, and between the two types of fracture. Using VBM, we found spatially heterogeneous volumetric bone mineral density differences between control subjects and subjects with hip fracture that varied by fracture type. Interestingly, femoral neck fracture subjects, but not subjects with trochanteric fracture, showed significantly lower volumetric bone mineral density in the superior aspect of the femoral neck compared with controls. Using surface-based SPM, we found that compared with controls, both fracture types showed thinner cortices in regions in agreement with the type of fracture. Most outcomes of cortical and endocortical volumetric bone mineral density comparisons were consistent with VBM results. Our results suggest: 1) that the spatial distribution of trabecular volumetric bone mineral density might play a significant role in hip fracture; 2) that focal cortical bone thinning might be more relevant in femoral neck fractures; and 3) that areas of reduced cortical and endocortical volumetric bone mineral density might be more relevant for trochanteric fractures in Chinese women. © 2017 American Society for Bone and Mineral Research.

Lean body mass, consisting mostly of skeletal muscle, is important for healthy aging. We performed a genome-wide association study for whole body (20 cohorts of European ancestry with n = 38,292) and appendicular (arms and legs) lean body mass (n = 28,330) measured using dual energy X-ray absorptiometry or bioelectrical impedance analysis, adjusted for sex, age, height, and fat mass. Twenty-one single-nucleotide polymorphisms were significantly associated with lean body mass either genome wide (p

Bone mineral density (BMD) has been linked to mortality, but little is known about the independent contribution of each endosteal bone compartment and also the rate of bone loss to risk of mortality. We examined the relationships between (1) baseline trabecular and cortical volumetric BMD (vBMD) at the proximal femur, and (2) the rate of trabecular and cortical bone loss and all-cause mortality in older adults from the AGES-Reykjavik study. The analysis of trabecular and cortical vBMD and mortality was based on the baseline cohort of 4654 participants (aged ≥66 years) with a median follow-up of 9.4 years; the association between rate of bone loss and mortality was based on 2653 participants with bone loss data (median follow-up of 5.6 years). Analyses employed multivariable Cox-proportional models to estimate hazard ratios (HRs) with time-varying fracture status; trabecular and cortical variables were included together in all models. Adjusted for important confounders, Cox models showed that participants in the lowest quartile of trabecular vBMD had an increased risk of mortality compared to participants in other quartiles (HR = 1.12; 95% confidence interval (CI), 1.01 to 1.25); baseline cortical vBMD was not related to mortality (HR = 1.08; 95% CI, 0.97 to 1.20). After adjustment for time-dependent fracture status, results were attenuated and not statistically significant. A faster loss (quartile 1 versus quartiles 2-4) in both trabecular and cortical bone was associated with higher mortality risk (HR = 1.37 and 1.33, respectively); these associations were independent of major potential confounders including time-dependent incident fractures (HR = 1.32 and 1.34, respectively). Overall, data suggest that faster bone losses over time in both the trabecular and cortical bone compartments are associated with mortality risk and that measurements of change in bone health may be more informative than single-point measurements in explaining mortality differences in older adults. © 2017 American Society for Bone and Mineral Research.

Genome-wide association studies (GWAS) have revealed numerous loci for areal bone mineral density (aBMD). We completed the first GWAS meta-analysis (N = 15,275) of lumbar spine volumetric BMD (vBMD) measured by quantitative computed tomography (QCT), allowing for examination of the trabecular bone compartment. SNPs that were significantly associated with vBMD were also examined in two GWAS meta-analyses to determine associations with morphometric vertebral fracture in (N = 21,701) and clinical vertebral fracture (N = 5,893). Expression QTL analyses of iliac crest biopsies were performed in 84 postmenopausal women, and murine osteoblast expression of genes implicated by eQTL or by proximity to vBMD-associated SNPs was examined. We identified significant vBMD associations with five loci, including 1p36.12, containing WNT4 and ZBTB40; 8q24, containing TNFRSF11B; and 13q14, containing AKAP11 and TNFSF11. Two loci (5p13 and 1p36.12) also contained associations with radiographic and clinical vertebral fracture, respectively. In 5p13, rs2468531 (minor allele frequency [MAF] = 3%) was associated with higher vBMD (β = 0.22, p = 1.9 × 10(-8) ) and decreased risk of radiographic vertebral fracture (OR = 0.75; false discovery rate [FDR] p = 0.01). In 1p36.12, rs12742784 (MAF = 21%) was associated with higher vBMD (β = 0.09, p = 1.2 × 10(-10) ) and decreased risk of clinical vertebral fracture (OR =0.82; FDR p = 7.4 × 10(-4) ). Both SNPs are non-coding and were associated with increased mRNA expression levels in human bone biopsies: rs2468531 with SLC1A3 (β = 0.28, FDR p = 0.01, involved in glutamate signaling and osteogenic response to mechanical loading) and rs12742784 with EPHB2 (β = 0.12, FDR p = 1.7 × 10(-3) , functions in bone-related ephrin signaling). Both genes are expressed in murine osteoblasts. This is the first study to link SLC1A3 and EPHB2 to clinically relevant vertebral osteoporosis phenotypes. These results may help elucidate vertebral bone biology and novel approaches to reducing vertebral fracture incidence. This article is protected by copyright. All rights reserved.

In der vorliegenden Forschungsarbeit wurden drei unterschiedliche Nanomaterialien untersucht, welche unter physiologischen Bedingungen ein unterschiedliches Verhalten aufwiesen. Bei diesen Materialien handelte es sich um stabilisatorfreie Legierungs-Nanopartikel aus der Laser-Ablation, amorphe Silica- sowie um Poly(organosiloxan) Nanopartikel. Im Hinblick auf in vitro Zellstudien wurde eine Größencharakterisierung in Zellmedium in Gegenwart von Proteinen aus fötalem Rinderserum durchgeführt. Um Vorteile einzelner Charakterisierungsmethoden zu kombinieren und gleichzeitig Nachteile zu kompensieren, wurden zur umfangreichen Charakterisierung die Statische Lichtstreuung, die Dynamische Lichtstreuung sowie die Asymmetrische Fluss Feld-Fluss Fraktionierung angewandt. Weiterhin wurde die Asymmetrische Fluss Feld-Fluss Fraktionierung mit einem online MALLS Detektor gekoppelt. Es handelt sich hierbei um einen Prototyp, bei dem durch einen hydrodynamisch fokussierten Probestrahl eine Minimierung des Probevolumens erfolgt. Die Legierungs-Nanopartikel wiesen unter physiologischen Salzbedingungen eine nur unzureichende elektrostatische Stabilität auf, zeigten jedoch höhere Stabilität in Gegenwart von Serumproteinen. Im Gegensatz hierzu waren amorphe Silica Nanopartikel unter hohen Salzkonzentrationen stabil, aggregierten jedoch in Gegenwart von Proteinen. Das Agglomerationsverhalten der amorphen Silica Nanopartikel wurde genauer untersucht, indem hierauf ein in dieser Arbeit hergeleitetes Modell der Wachstumsfunktionen von Teilchen-Cluster- und Cluster-Cluster-Aggregaten angewandt wurde. Poly(organosiloxan) Nanopartikel wiesen in Gegenwart von Serumproteinen keine Aggregate auf. Anhand dieser Probe wurde die Dicke der Proteinkorona durch ein statisches Lichtstreuexperiment bestimmt, welches einen alternativen Zugang zu bereits etablierten Methoden wie der Dynamischen Lichtstreuung, der Fluoreszenz Korrelationsspektroskopie oder dem Particle Tracking darstellt. Als Ergebnis konnte für die Koagulation amorpher Silica Nanopartikel in Gegenwart von Serumproteinen der Mechanismus der verbrückenden Flockung nachgewiesen werden. Der Flockungsprozess war nach 10 Minuten abgeschlossen. Weiterhin war die Anzahl der gebildeten Brücken unabhängig von der vorhandenen Partikelzahl konstant, jedoch bestimmte die Größe der ursprünglichen Nanopartikel die absolute Anzahl der gebildeten Verbrückungen. Amorphe Silica Nanopartikel mit einem Radius von 10 und 15 nm wurden mit einem Faktor von 40 effizienter verbrückt als Partikel mit einem Radius von 60 nm. Die Anzahl der Proteine pro Verbrückung sowie ein größerer sterisch unzugänglicher Bereich nahe der Verbrückungsstelle sind für die geringere Verbrückungseffizienz großer Teilchenspezies verantwortlich. Die Proteinkorona auf Poly(organosiloxan) Nanopartikeln wurde auf eine Dicke von 1,5 nm bestimmt. Diese verkleinerte sich durch PEGylierung des Nanomaterials auf eine Dicke von 0,4 nm. Diese Funde wurden mittels Asymmetrischer Fluss Feld-Fluss Fraktionierung bestätigt. Unter der Annahme starrer Proteine entsprechen diese Werte einer Oberflächenbedeckung von 48% bzw. 12%. Im Falle der nicht- PEGylierten Probe wurde die scheinbar unvollständige Oberflächenbelegung aufgrund der Entfaltung der Proteine auf kolloidalen Oberflächen erhalten. Zusätzlich entstehen bei statistischer Verteilung adsorbierter Proteine keine Dichtestpackungen, sondern sterisch unzugängliche Bereiche auf der Nanopartikel Oberfläche, wodurch die maximale Oberflächenbelegung nicht 100% entspricht. In this study, three different kinds of nanomaterials were investigated revealing diverse properties under physiological conditions. These were stabilizer free alloy nanoparticles from laser ablation, amorphous silica and poly(organosiloxane) nanoparticles. With regards to in vitro cell studies, size characterization of nanoparticles took place in cell culture media in presence of fetal bovine serum proteins. To combine the benefits of different characterization techniques and to compensate single drawbacks, Static Light Scattering, Dynamic Light Scattering and Asymmetrical Flow Field-Flow Fractionation were applied. Furthermore, the coupling of Asymmetrical Flow Field-Flow Fractionation to a prototype online MALLS detector offering minimal sample volume was established. The alloy nanoparticles exhibited insufficient electrostatic stabilization at physiological salt conditions, however featuring increased stability after serum protein adsorption. In contrast amorphous silica nanoparticles were stable at high salt conditions and aggregates were formed rapidly in presence of proteins. Hence, agglomeration behavior of silica nanoparticles was investigated in detail by applying a model describing growth behavior of particle-cluster and cluster-cluster aggregates, which was also derived in this study. Poly(organosiloxane) nanoparticles did not show any aggregation behavior, though the thickness of the protein corona was investigated by applying Static Light Scatting experiments representing an alternative approach to already established methods such as Dynamic Light Scattering, Fluorescence Correlations Spectroscopy or Particle Tracking. As result for silica nanoparticles in presence of proteins, evidence for the mechanism of bridging flocculation was provided. The flocculation process was completed after 10 minutes. Furthermore, the number of bridges was observed being constant independent of the number of particles present. However the size of the pristine nanomaterial determined the absolute number of bridges. Amorphous silica nanoparticles with a radius of 10 nm and 15 nm were bridged more efficiently with a factor of 40, compared to amorphous silica nanoparticles with a radius of 60 nm. The number of proteins participating in a bridge, as well as an increased area of steric hindrance close to the bridging location, was responsible for a loss of bridging efficiency of proteins in case of larger silica particle species. The protein corona onto poly(organosiloxane) nanoparticles exhibited a size of 1.5 nm. By PEGylation of the nanomaterial, the corona decreased to a size of 0.4 nm. These obervations were confirmed by Asymmetrical Flow Field-Flow Fractionation experiments. These thicknesses corresponded to surface coverage of 48% and 12%, respectively, considering rigid proteins. The apparent incomplete surface coverage of the non-PEGylated sample is a result of the unfolding of proteins at colloidal surfaces. Additionally, a statistically arrangement of adsorbed proteins does not lead to a compact packing, instead spots of unapproachable surface will be formed, which lower the maximum surface coverage directly.

Ergibt sich aus dem pränatalen Ultraschallbefund oder durch klinische Hinweise der Verdacht auf eine Entwicklungsstörung des Darms des Neugeborenen, so ist die Situation am sichersten durch eine Röntgenaufnahme, und zwar des Thorax und Abdomens im Liegen oder im Hängen, zu klären.

Zahlreiche Erkrankungen gehen mit einer Vergrößerung der Leber einher. In den einzelnen Altersgruppen verteilen sich die möglichen Diagnosen in ihrer Häufigkeit sehr unterschiedlich. Neben entzündlichen Prozessen in der Leber können Stoffwechsel- und infiltrative Erkrankungen sowie Veränderungen des Blutflusses in der Leber oder Gallenwegerkrankungen mit einer Hepatomegalie in ursächlichem Zusammenhang stehen.

Die Leber spielt eine zentrale Rolle in der Bereitstellung von Energie, der Synthese von Proteinen und Peptiden sowie der Metabolisierung von Lipiden und Kohlenhydraten. Chronische Erkrankungen der Leber führen unweigerlich zu erheblichen Problemen der körperlichen Entwicklung, einer verminderten Gewichtszunahme und einem verzögerten Längenwachstum bis hin zum Wachstumsstillstand. Gerade Kleinkinder mit chronischen cholestatischen Erkrankungen sind durch eine Malnutrition gefährdet.

Systemerkrankungen als Ursache einer Lebererkrankung sind häufig, ohne dass man genaue Zahlen angeben kann. Die verschiedenen Grunderkrankungen sind für sich betrachtet zwar selten, nur dadurch, dass viele Erkrankungen in Betracht gezogen werden müssen, ergibt sich eine relative Häufung. Durch Fortschritte auf dem Gebiet der molekularbiologischen Diagnostik insbesondere bei den Stoffwechselerkrankungen lassen sich heute bereits viele der in Frage kommenden Grunderkrankungen eindeutig nachweisen. Allerdings ist bei keiner der Erkrankungen ein hundertprozentiger molekularbiologischer Nachweis möglich. Damit ergibt sich eine sichere Diagnose nur bei einem positiven Nachweis. Bei fehlendem Nachweis einer bisher bekannten für die Erkrankung spezifischen Mutation bleibt die Zuordnung entweder enzymatischen Tests oder klinischer Diagnose vorbehalten. Insbesondere bei der Manifestation als akutes Leberversagen ist die für die Diagnosesicherung erforderliche Zeit damit oft nicht vorhanden.

Muscle composition may affect mortality risk, but prior studies have been limited to specific samples or less precise determination of muscle composition. We evaluated associations of thigh muscle composition, determined using computed tomography imaging, and knee extension strength with mortality risk among 4,824 participants aged 76.4 (standard deviation (SD), 5.5) years from the Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study (2002-2006). Cox proportional hazards models were used to estimate hazard ratios. After 8.8 years of follow-up, there were 1,942 deaths. For men, each SD-increment increase in muscle lean area, muscle quality, and strength was associated with lower mortality risk, with decreases ranging between 11% and 22%. Each SD-increment increase in intermuscular adipose tissue and intramuscular adipose tissue was associated with higher mortality risk (hazard ratio (HR) = 1.13 (95% confidence interval (CI): 1.06, 1.22) and HR = 1.23 (95% CI: 1.15, 1.30), respectively). For women, each SD-increment increase in muscle lean area, muscle quality, and strength was associated with lower mortality risk, with decreases ranging between 12% and 19%. Greater intramuscular adipose tissue was associated with an 8% higher mortality risk (HR = 1.08, 95% CI: 1.01, 1.16). This study shows that muscle composition is associated with mortality risk. These results also show the importance of improving muscle strength and area and lowering muscle adipose tissue infiltration.

Muscle composition may affect mortality risk, but prior studies have been limited to specific samples or less precise determination of muscle composition. We evaluated associations of thigh muscle composition, determined using computed tomography imaging, and knee extension strength with mortality risk among 4,824 participants aged 76.4 (standard deviation (SD), 5.5) years from the Age, Gene/Environment Susceptibility (AGES)-Reykjavik Study (2002-2006). Cox proportional hazards models were used to estimate hazard ratios. After 8.8 years of follow-up, there were 1,942 deaths. For men, each SD-increment increase in muscle lean area, muscle quality, and strength was associated with lower mortality risk, with decreases ranging between 11% and 22%. Each SD-increment increase in intermuscular adipose tissue and intramuscular adipose tissue was associated with higher mortality risk (hazard ratio (HR) = 1.13 (95% confidence interval (CI): 1.06, 1.22) and HR = 1.23 (95% CI: 1.15, 1.30), respectively). For women, each SD-increment increase in muscle lean area, muscle quality, and strength was associated with lower mortality risk, with decreases ranging between 12% and 19%. Greater intramuscular adipose tissue was associated with an 8% higher mortality risk (HR = 1.08, 95% CI: 1.01, 1.16). This study shows that muscle composition is associated with mortality risk. These results also show the importance of improving muscle strength and area and lowering muscle adipose tissue infiltration.

Nonpharmacologic approaches to preserve or increase bone mineral density (BMD) include whole-body vibration (WBV), but its efficacy in elderly persons is not clear. Therefore, we conducted the Vibration to Improve Bone in Elderly Subjects (VIBES) trial, a randomized, placebo-controlled trial of 10 minutes of daily WBV (0.3g at 37 Hz) in seniors recruited from 16 independent living communities. The primary outcomes were volumetric BMD of the hip and spine measured by quantitative computed tomography (QCT) and biochemical markers of bone turnover. We randomized 174 men and women (89 active, 85 placebo) with T-scores -1 to -2.5 who were not taking bone active drugs and had no diseases affecting the skeleton (mean age 82 ± 7 years, range 65 to 102). Participants received daily calcium (1000 mg) and vitamin D (800 IU). Study platforms were activated using radio frequency ID cards providing electronic adherence monitoring; placebo platforms resembled the active platforms. In total, 61% of participants in the active arm and 73% in the placebo arm completed 24 months. The primary outcomes, median percent changes (interquartile range [IQR]) in total volumetric femoral trabecular BMD (active group (2.2% [-0.8%, 5.2%]) versus placebo 0.4% [-4.8%, 5.0%]) and in mid-vertebral trabecular BMD of L1 and L2 (active group (5.3% [-6.9%, 13.3%]) versus placebo (2.4% [-4.4%, 11.1%]), did not differ between groups (all p values > 0.1). Changes in biochemical markers of bone turnover (P1NP and sCTX) also were not different between groups (p = 0.19 and p = 0.97, respectively). In conclusion, this placebo-controlled randomized trial of daily WBV in older adults did not demonstrate evidence of significant beneficial effects on volumetric BMD or bone biomarkers; however, the high variability in vBMD changes limited our power to detect small treatment effects. The beneficial effects of WBV observed in previous studies of younger women may not occur to the same extent in elderly individuals.

The International Society for Clinical Densitometry (ISCD) has developed new official positions for the clinical use of computed tomography (CT) scans acquired without a calibration phantom, for example, CT scans obtained for other diagnosis such as colonography. This also addresses techniques suggested for opportunistic screening of osteoporosis. The ISCD task force for quantitative CT reviewed the evidence for clinical applications of these new techniques and presented a report with recommendations at the 2015 ISCD Position Development Conference. Here we discuss the agreed upon ISCD official positions with supporting medical evidence, rationale, controversy, and suggestions for further study. Advanced techniques summarized as statistical parameter mapping methods were also reviewed. Their future use is promising but the clinical application is premature. The clinical use of QCT of the hip is addressed in part I and of finite element analysis of the hip and spine in part II.