Diffraction from the beta-sheet crystallites in spider silk

We analyze the wide angle x-ray scattering from oriented spider silk fibers in terms of a quantitative scattering model, including both structural and statistical parameters of the $\beta$-sheet crystallites of spider silk in the amorphous matrix. The model is based on kinematic scattering theory and allows for rather general correlations of the positional and orientational degrees of freedom, including the crystallite's size, composition and dimension of the unit cell. The model is evaluated numerically and compared to experimental scattering intensities allowing us to extract the geometric and statistical parameters. We show explicitly that for the experimentally found mosaicity (width of the orientational distribution) inter-crystallite effects are negligible and the data can be analyzed in terms of single crystallite scattering, as is usually assumed in the literature.Comment: 15 pages, 14 figures, on average 0.93 figures per pag

Nanoscale structure of type I collagen fibrils: Quantitative measurement of D‐spacing

This article details a quantitative method to measure the D‐periodic spacing of type I collagen fibrils using atomic force microscopy coupled with analysis using a two‐dimensional fast fourier transform approach. Instrument calibration, data sampling and data analysis are discussed and comparisons of the data to the complementary methods of electron microscopy and X‐ray scattering are made. Examples of the application of this new approach to the analysis of type I collagen morphology in disease models of estrogen depletion and osteogenesis imperfecta (OI) are provided. We demonstrate that it is the D‐spacing distribution, not the D‐spacing mean, that showed statistically significant differences in estrogen depletion associated with early stage osteoporosis and OI. The ability to quantitatively characterize nanoscale morphological features of type I collagen fibrils will provide important structural information regarding type I collagen in many research areas, including tissue aging and disease, tissue engineering, and gene knockout studies. Furthermore, we also envision potential clinical applications including evaluation of tissue collagen integrity under the impact of diseases or drug treatments. The distribution of Type I collagen fibril D‐spacing provides important morphological information regarding Type I collagen in diseases such as early stages of osteoporosis and osteogenesis Imperfecta . In this article, the authors use Atomic Force Microscopy (AFM) imaging combined with two Dimensional Fast Fourier Transform (2D FFT) analysis to quantitatively assess Type I collagen fibril D‐spacing. This methodology allows imaging and characterization of Type I collagen constituted biological tissues, hydrogels, and other collagen based biomaterials.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/94732/1/117_ftp.pdfhttp://deepblue.lib.umich.edu/bitstream/2027.42/94732/2/biot_201200174_sm_suppinfo.pd

Body wall structure in the starfish Asterias rubens

Queen Mary University of London; Engineering & Physical Sciences Research Council. Grant Number: EP/J501360/1; Biotechnology and Biological Sciences Research Council. Grant Number: BBSRC;BB/M001644/1; Royal Society through the Equipment Grant scheme. Grant Number: SEMF1A6

Rough Fibrils Provide a Toughening Mechanism in Biological Fibers

Spider silk is a fascinating natural composite material. Its combination of strength and toughness is unrivalled in nature, and as a result, it has gained considerable interest from the medical, physics, and materials communities. Most of this attention has focused on the one to tens of nanometer scale: predominantly the primary (peptide sequences) and secondary (β sheets, helices, and amorphous domains) structure, with some insights into tertiary structure (the arrangement of these secondary structures) to describe the origins of the mechanical and biological performance. Starting with spider silk, and relating our findings to collagen fibrils, we describe toughening mechanisms at the hundreds of nanometer scale, namely, the fibril morphology and its consequences for mechanical behavior and the dissipation of energy. Under normal conditions, this morphology creates a nonslip fibril kinematics, restricting shearing between fibrils, yet allowing controlled local slipping under high shear stress, dissipating energy without bulk fracturing. This mechanism provides a relatively simple target for biomimicry and, thus, can potentially be used to increase fracture resistance in synthetic materials

Human adipose derived stem cells are superior to human osteoblasts (HOB) in bone tissue engineering on a collagen-fibroin-ELR blend

The ultrastructure of the bone provides a unique mechanical strength against compressive, torsional and tensional stresses. An elastin-like recombinamer (ELR) with a nucleation sequence for hydroxyapatite was incorporated into films prepared from a collagen – silk fibroin blend carrying microchannel patterns to stimulate anisotropic osteogenesis. SEM and fluorescence microscopy showed the alignment of adipose-derived stem cells (ADSCs) and the human osteoblasts (HOBs) on the ridges and in the grooves of microchannel patterned collagen-fibroin-ELR blend films. The Young's modulus and the ultimate tensile strength (UTS) of untreated films were 0.58 ± 0.13 MPa and 0.18 ± 0.05 MPa, respectively. After 28 days of cell culture, ADSC seeded film had a Young's modulus of 1.21 ± 0.42 MPa and UTS of 0.32 ± 0.15 MPa which were about 3 fold higher than HOB seeded films. The difference in Young's modulus was statistically significant (p: 0.02). ADSCs attached, proliferated and mineralized better than the HOBs. In the light of these results, ADSCs served as a better cell source than HOBs for bone tissue engineering of collagen-fibroin-ELR based constructs used in this study. We have thus shown the enhancement in the tensile mechanical properties of the bone tissue engineered scaffolds by using ADSCs

im Hinblick auf Verteilung, Häufigkeit und semantischem Gehalt

Abweichender Titel laut Übersetzung der Verfasserin/des VerfassersZsfassung in engl. SpracheSeit den frühesten Anfängen der Siedlungstätigkeit in Europa wurden Riednamen zur Bezeichnung und Abgrenzung der in privatem Eigentum stehenden Grundflächen außerhalb der bebauten Siedlungsstrukturen verwendet. In dieser Eigenschaft fanden die Riednamen Eingang in Chroniken und Urbare (erste Grundbücher) und wurden später in die Katasterwerke der modernen Grundbuchführung übernommen.Dem Bundesamt für Eich- und Vermessungswesen (BEV) ist es in den letzten Jahren gelungen das Riednamengut aus historisch unterschiedlichen Katasterwerken ausgehend von der "Urmappe" der Franziszeischen Landesaufnahme (1817-1861) zu extrahieren und in der sogenannten "Riednamendatenbank" zu speichern. In einer analytischen Betrachtung wird in der hier vorliegenden Diplomarbeit anhand verschiedener Fragestellungen versucht, Funktion und Bedeutung von Riednamen herauszuarbeiten und zu untersuchen inwiefern das Riednamengut durch entwicklungsbedingte Veränderungen des Siedlungsraumes selbst einer Veränderung unterliegt. Das Ziel dieser Arbeit war es zu untersuchen, ob Riednamen auch in der Gegenwart noch einen Bezug zu ihrer Umgebung darstellen und in Bedeutung und Funktion immer noch relevant sind. Neben einem Überblick über die historische Entwicklung der Riednamen und einem Einblick in die sprachwissenschaftlichen Methoden und Erkenntnisse der modernen Onomastik die über den Bedeutungshintergrund von Riednamen reflektieren, beschäftigt sich der erste Teil der Arbeit mit der Funktion der Riede im Franziszeischen Kataster, der als der Grundstein des modernen Katasterwesens gilt.Im zweiten Teil der Arbeit werden die Mengen- und Größenverhältnisse der Riednamendatenbank untersucht. Mit statistischen Methoden werden Häufigkeiten und Flächenverteilung der Riednamen in Österreich dargestellt. In einem zweiten Schritt werden Bedeutung und topographischer Bezug ausgewählter Riednamen anhand ihres semantischen Aussagegehalts mit Hilfe eines analytischen Abgleichs mit der Amtlichen Österreich Karte 1:50.000 (ÖK50) überprüft. Die Veränderung von Riednamen in urbanen Regionen wird anhand einer Dokumentation von Namen im 23. Wiener Gemeindebezirk betrachtet.Abschließend werden Bekanntheitsgrad, Aktualität und Relevanz der Riednamen in ausgewählten Regionen anhand von Personenbefragungen analysiert.Since the earliest settlement activities in Europe, field names (Riednamen) were used to designate private land plots outside the inhabited areas. These names indicate special attributes or conditions of the land site, like property rights, fertility, local position and so on. Through this reed names are very close to social structures and therefore undergoing permanent transformation as social structures change over the centuries. Reed names also became part of chronicles and were later inherited to cadastres. During the last years the Bundesamt für Eich- und Vermessungswesen (BEV) has managed to extract all reed names from several cadastres, starting from the so called "Urmappe" of the Franciscan cadastre in 19th century, and to store them in a local Database. This database is part of the Name section called GEONAM of Austria's Digital Landscape Model (DLM) operated by the BEV.This thesis gives an analytic overview about meaning and function of reed names in Austria and their transformation due to urbanization. The aim of this thesis was to examine if reed names today are still relating to their environment and despite of cultural changes are still relevant to people. The first part of the thesis focuses on the historic development of reed names. And reflects about the meaning of reed names and gives a short overview of linguistic methods and results of modern onomatology. The Franciscan cadastre and the functions reed names were applied to within is another topic of the first part. The main subject of this thesis, following in the second part, is to analyze the bulk of names in the reed name database under 3 aspects.The first approach was to analyze the database under a quantitative point of view. Freuqentness and allocation of the reed names in Austria werde described with statistical methods.The second approach is to analyze the reed names with qualitative methods. In particular the names were to be examined on their possible semantic content. This part of the analysis compared selected names to the topographical information of the Austrian map scale 1:50.000 (ÖK50) in its digital version.The transformation reed names are undergoing due to changing settlement patterns was examined with examples of several reed names in Viennas 23rd district and described in a foto documentation. The last part of the analysis points out the level of awareness, the actuality and the use of reed names in daily life. For that reason interviews were held in specified rural- and urban regions in Austria.19

Das bionische Exoskelett in der Anwendung bei Querschnittpatient*innen. Expert*innenerhebung der Usability und Akzeptanz des derzeit in Österreich gängigen Modells

Hintergrund: Die Technologieentwicklung hat in den letzten Jahren unglaubliche Fortschritte gemacht und dadurch haben auch roboter-unterstütze Therapieformen in der Physiotherapie Einzug gehalten. Seit wenigen Jahren sind Exoskelette im medizinischen Bereich zugelassen und werden zunehmend zur Ganganbahnung und Gangschulung bei Querschnittpatient*innen eingesetzt. Diese Arbeit ist eine Usability-Erhebung bei Expert*innen, welche das in Österreich meist verwendete Exoskelett im Rehabilitationsbereich anwenden. Es soll die Anwenderfreundlichkeit und Akzeptanz der Gehroboter erhoben werden. Methode: In der Arbeit wurde eine Usability-Erhebung mittels semi-strukturierter Interviews von sechzehn zertifizierten Physiotherapeut*innen, welche in Österreichs Therapiezentren mit den Gehrobotern arbeiten, durchgeführt. Zu Beginn wurde eine Literaturrecherche durchgeführt. Da Exoskelette erst seit kurzer Zeit eine Zulassung im medizinischen Bereich aufweisen, ist dieses Thema noch sehr wenig erforscht. Die semistrukturierten Interviews wurden mittels einer qualitativen Inhaltsanalyse nach Mayring ausgewertet. Es wurden Kategorien gebildet und danach einem kritischen Diskurs unterworfen. Ergebnisse: Die befragten Physiotherapeut*innen sind durchwegs zufrieden mit der Usability des in Österreich verwendeten Exoskeletts. Die Therapeut*innen wüschen sich Verbesserungen beim Display und der Fixation der Beine, um den Erhalt der physiologischen Beinachse während des Gehens zu gewährleisten. Das Exoskelett hat mittlerweile eine hohe Akzeptanz als Gangschulungsgerät seitens der Physiotherapeut*innen. Diese wüschen sich aber weitere Modifikationen und Erweiterungen einiger Tools des Exoskeletts. Conclusio: Physiotherapeut*innen ziehen die Verwendung des Exoskeletts bei vielen Patient*innen anderen Gangschulungsgeräten vor, da es schneller in der Anwendung ist und ein gutes physiologisches Gangbild hervorbringt. Die Expert*innen wünschen sich aber weitere Verbesserungen.Background: The technology development has made incredible progress in recent years, and this has also helped robotic forms of therapy in the field of physiotherapy. In recent years, exoskeletons have been approved in the medical field and are increasingly being used for graft initiation and gait training in paraplegic patients. This work is a usability survey among the experts who apply the most commonly used exoskeleton in the rehabilitation sector in Austria. The aim of this study is to ascertain the user-friendliness and acceptance of walking robots. Method: Following a literature review, this work presents the outcome of a usability survey by means of semi-structured interviews of sixteen certified physiotherapists who work with walking robots in Austria's therapy centers. Since exoskeletons have only recently been approved in the medical field, few reports exist to date. The semi-structured interviews were evaluated with qualitative content analysis according to Mayring. Categories were formed and subjected to critical discourse. Results: The physiotherapists interviewed are thoroughly satisfied with the usability of the exoskeleton used in Austria. Therapists are looking for improvements in display and leg fixation to help maintain the physiological axis of the leg while walking. The exoskeleton now has a high acceptance as a gait training device by the physiotherapists. These, however, continue to require modifications and expansion of some tools of the exoskeleton. Conclusion: Physiotherapists prefer the use of the exoskeleton in many patients to other gait training equipment because it is efficient in its use and produces a good physiological gait pattern. The experts, however, wish for further improvements.Wien, FH Campus Wien, Masterarb., 2019(VLID)446789

Therapy resistant urticaria as a long-term symptom of an incomplete Schnitzler syndrome

Abstract Background Recurring therapy resistant hives, accompanied by IgM-gammopathy, fever and joint pain can indicate Schnitzler syndrome, a rare autoimmune disorder. There is currently no approved treatment, but complete remission of symptoms can be induced with IL-1 antagonists. Case presentation A patient with a history of chronic urticaria presented frequently at the outpatient clinic with severe hives and was treated unsuccessfully with antihistamines and omalizumab. After several years, additional symptoms such as joint pain, recurrent fever, and IgM-gammopathy developed. After the diagnostic criteria for Schnitzler syndrome were met, treatment with anakinra was initiated and resulted in an improvement of the symptoms. Shortly after the first injection, the patient developed large and painful erythematous lesions at the injection sites, leading to discontinuation of treatment and a rapid recurrence of symptoms. Subsequently, treatment with a longer-acting IL-1 antagonist (canakinumab) was initiated, resulting in a complete remission of symptoms. Conclusion This case report demonstrates that patients with urticarial symptoms that are not relieved by typical treatments should prompt repeated reassessments of the diagnosis, even years later, because gammopathy and other diagnostic criteria for Schnitzler syndrome can occur with a delay