878 research outputs found
A sweet response to a sour situation: The role of soluble pattern recognition receptors in the innate immune response to invasive Aspergillus fumigatus infections
Serum opsonin ficolin-A enhances host-fungal interactions and modulates cytokine expression from human monocyte-derived macrophages and neutrophils following Aspergillus fumigatus challenge.
Invasive aspergillosis is a devastating invasive fungal disease associated with a high mortality rate in the immunocompromised, such as leukaemia patients, transplant patients and those with HIV/AIDS. The rodent serum orthologue of human L-ficolin, ficolin-A, can bind to and opsonize Aspergillus fumigatus, the pathogen that causes invasive aspergillosis, and may participate in fungal defence. Using human monocyte-derived macrophages and neutrophils isolated from healthy donors, we investigated conidial association and fungal viability by flow cytometry and microscopy. Additionally, cytokine production was measured via cytometric bead arrays. Ficolin-A opsonization was observed to significantly enhance association of conidia, while also inhibiting hyphal growth and contributing to increased fungal killing following incubation with monocyte-derived macrophages and neutrophils. Additionally, ficolin-A opsonization was capable of manifesting a decrease in IL-8, IL-1ÎČ, IL-6, IL-10 and TNF-α production from MDM and IL-1ÎČ, IL-6 and TNF-α from neutrophils 24 h post-infection. In conclusion, rodent ficolin-A is functionally comparable to human L-ficolin and is capable of modulating the innate immune response to A. fumigatus, down-regulating cytokine production and could play an important role in airway immunity
Empirical essays on macroeconomic shocks and financial markets
This dissertation has the objective to further foster the understanding of this interrelation by examining the impact of macroeconomic shocks on financial markets. The three chapters of this dissertation investigate the impact of macroeconomic shocks on asymmetric information, stock returns, and corporate investment activity. Chapter II provides empirical support for the assumption of Bernanke et al. (1994), who argue that financial markets can accelerate macroeconomic shocks by increasing the cost of capital and thereby decreasing economic activity. Chapter III identifies the uneven distribution of US recessions and expansions between Democratic and Republican presidencies as the source of the presidential puzzle, the return anomaly that US market returns are higher under Democratic presidents compared to Republican presidents. Chapter IV documents systematic cross-sectional differences in the way firms adapt their capital level in response to macroeconomic shocks and relates this cross-sectional heterogeneity to known stock return patterns: size premium, book-to-market premium, and investment intensity premium. In conclusion, this dissertation identifies new channels through which macroeconomic shocks impact financial markets. Thereby, this dissertation adds insights about the
relation between financial markets and the real economy
Digitalization in the Global South
What are opportunities and risks of ICT in a global context from an ethical and interdisciplinary point of view? This TATuP special topic addresses often neglected issues, like unequal power relations, neo-colonialism, (digital) illiteracy, general barriers to access, or the gender digital divide.
Editors: J. Heesen, L. Schelenz, K. Schopp and M. PawelecWhat are opportunities and risks of ICT in a global context from an ethical and interdisciplinary point of view? This TATuP special topic addresses often neglected issues, like unequal power relations, neo-colonialism, (digital) illiteracy, general barriers to access, or the gender digital divide.
Editors: J. Heesen, L. Schelenz, K. Schopp and M. Pawele
Concurrent validity of VmaxPro, Kinovea, and Speedograph for the assessment of peak barbell velocity during the bench press: A comparison of technological approaches and historical evolutions
Measurement of barbell velocity is a simple and effective way to control strength training. To assess the concurrent validity of different technological approaches measuring barbell velocity, video-analysis (Kinovea), linear velocity transducer (Speedograph), and an inertial measurement unit (VmaxPro) were compared. Sixty-eight female and male sport science students lifted two repetitions in the bench press exercise at self-selected barbell loads. Peak vertical barbell velocity (Vmax) was parallel measured during the concentric phase of the lift using the aforementioned devices. Concordance correlation coefficient (CCC), Deming regression (DR) and Bland-Altman analysis (BA) were used to assess relative and absolute concurrent validity of Vmax measured with Kinovea, Speedograph, and VmaxPro. Results confirmed high concurrent validity of Speedograph and VmaxPro (CCC = 0.99, standard deviation of differences [SDD] = 0.04 mâs-1) without detecting proportional or constant bias. In contrast, Vmax measured with Kinovea showed poor concurrent validity to Speedograph (CCC = 0.83) and VmaxPro (CCC = 0.81) with significant proportional and constant bias. Regression based re-calibration of Vmax from Kinovea resulted in an SDD = 0.09 mâs-1 compared to Speedograph and an SDD = 0.08 mâs-1 compared to VmaxPro. Among the three tested devices, Vmax assessed using Kinovea showed poor concurrent validity. Furthermore, as Kinovea showed proportional bias compared to Speedograph and VmaxPro, application-specific re-calibration of Kinovea should be applied when barbell velocity data is compared to Speedograph and VmaxPro
Ethische Fragen zur Digitalisierung im Globalen SĂŒden: Perspektiven auf Gerechtigkeit und Gleichberechtigung
Digitalization and information and communications technology (ICT) influence and transform the world economy, our everyday life, politics, and our way of communicating. This entails opportunities and benefits as well as risks, challenges, and difficulties for all actors involved. Especially in the African context, but also in other countries of the Global South, there are important questions and aspects of digitalization which have to be addressed by technology assessment (TA) from an ethical point of view: questions of unequal power relations, neo-colonialism, (digital) illiteracy and language barriers, general barriers to access, and the gender digital divide. To broaden the perspectives of TA in global contexts, these issues should be discussed by different scientific disciplines, equally considering the positions of those affected. The inter- and transdisciplinary approaches in this TATuP special topic make a much-needed contribution to TA of digitalization in a global context.Digitalisierung und Informations- und Kommunikationstechnologien (IKT) beeinflussen und verĂ€ndern die Weltwirtschaft, unser Alltagsleben, die Politik und unsere Kommunikation. Das birgt Chancen und Vorteile, aber auch Risiken, Herausforderungen und Schwierigkeiten fĂŒr alle beteiligten Akteur*innen. Besonders im afrikanischen Kontext, aber auch in anderen LĂ€ndern des Globalen SĂŒdens, gibt es wichtige Fragen und Aspekte der Digitalisierung, die in der TechnikfolgenabschĂ€tzung (TA) von einem ethischen Standpunkt aus adressiert werden mĂŒssen: Fragen zu ungleichen MachtverhĂ€ltnissen, Neokolonialismus, (digitalem) Analphabetismus und sprachlichen Barrieren sowie zu allgemeinen Zugangsbarrieren und der digitalen Kluft zwischen den Geschlechtern. Um die Perspektive von TA in globalen Kontexten zu erweitern, sollten diese Fragen aus unterschiedlichen wissenschaftlichen Disziplinen heraus diskutiert und die Perspektive derjenigen miteinbezogen werden, die im konkreten Fall betroffen sind. Die inter- und transdisziplinĂ€ren AnsĂ€tze in diesem TATuP-Thema leisten einen wichtigen Beitrag zur TA der Digitalisierung im globalen Kontext
Untersuchung des Einflusses ausgewÀhlter Untergrundparameter auf die nachhaltige thermische Nutzung des oberflÀchennahen Untergrundes im urbanen Raum
Zur Deckung dieses Energiebedarfes zur WĂ€rme- und KĂ€lteversorgung im urbanen Raum hat sich die oberflĂ€chennahe Geothermie als erneuerbare Energiequelle bewĂ€hrt. Allerdings sind im Wohnsektor meist kleine, grundstĂŒcksbasierte Systeme in geringen AbstĂ€nden installiert. Diese intensive thermische Untergrundnutzung charakterisiert eine begrenzte Investitionssumme, sodass statt Untergrunddaten Literaturwerte fĂŒr die Systemplanung herangezogen werden. Zudem verhindert die grundstĂŒcksbasierte Betrachtungsskala die BerĂŒcksichtigung umliegender Untergrundnutzungen. Die Konsequenzen dieser vereinfachten Systemplanung, wurden in dieser Arbeit untersucht.
Im ersten Schritt wurden die fĂŒr die ErdwĂ€rmenutzung relevanten WĂ€rmetransportbedingungen identifiziert. Szenariensimulationen belegen den Einfluss der Grundwasserdynamik und der ungesĂ€ttigten Zone auf das geothermische Standortpotential. Je dichter ErdwĂ€rmesonden installiert sind, desto wichtiger ist das VerstĂ€ndnis standortspezifischer WĂ€rmetransportprozesse zur Bewertung der Wechselwirkungen zwischen benachbarten Systemen. Daher wurde im zweiten Schritt untersucht, wie standortspezifische Untergrundbedingungen diese Wechselwirkungen beeinflussen. Im Ergebnis zeigen Standorte mit einem hohen geothermischen Potential ein vergleichsweise geringes Risiko fĂŒr thermische Interaktionen.
Die Erhebung standortspezifischer Daten ist mit einem Mehraufwand fĂŒr die Erkundungsuntersuchungen verbunden. Es wurde geprĂŒft, inwieweit der Mehraufwand zu einer Steigerung der Systemeffizienz und -nachhaltigkeit beitrĂ€gt. DafĂŒr wurden AnsĂ€tze zur Untergrundparametrisierung anhand von Literaturwerten und standortspezifischen Messungen gegenĂŒbergestellt. FĂŒr eine effiziente und nachhaltige geothermische Untergrundbewirtschaftung bedarf es einer Betrachtungsskala ĂŒber die GrundstĂŒcksgrenzen hinaus. DafĂŒr wurde ein Konzept fĂŒr eine einheitliche geothermische ErschlieĂung urbaner Wohngebiete betrachtet, das sowohl die Investitionskosten fĂŒr die einzelnen WohnhĂ€user reduziert als auch die Planungssicherheit optimiert
Diversity and Social Justice in Technology Design: Reflections on Diversity-Aware Technology
An interdisciplinary endeavour at the intersection of American Studies, Critical Diversity Studies, as well as Science and Technology Studies, this article scrutinises so-called diversity-aware technology. A diversity-aware system is a computer system whose designers a) account for differences between the systemâs stakeholders, and/or b) draw on a normative notion of diversity like âinclusionâ or âfairnessâ in its design. Diversity concepts embedded in technology carry contested values and have effects on the technologyâs stakeholders. Therefore, it is vital to conduct a critical review of designs leveraging diversity concepts. In an exploration of three cases (diversity-aware datasets, machine learning fairness, and diversity-aware social media), the article sheds light on the shortcomings of mainstream or âindividual-levelâ diversity-aware technology. Such technology leverages individual-level notions of diversity (demographics, personality, culture) to cater to users, thereby obscuring social inequalities among them. Inspired by Black feminism and critical race theory, the article offers a social-justice-oriented conceptualisation of diversity-aware technology. It develops a definition and criteria for critical or âstructural-levelâ diversity-aware technology, where diversity concepts are linked to the visibility and redistribution of power. The article offers inspiration for researchers of technology and designers who work with diversity concepts
First hospital outbreak of the globally emerging Candida auris in a European hospital
Background: Candida auris is a globally emerging multidrug resistant fungal pathogen causing nosocomial transmission. We report an ongoing outbreak of C. auris in a London cardio-thoracic center between April 2015 and July 2016. This is the first report of C. auris in Europe and the largest outbreak so far. We describe the identification, investigation and implementation of control measures. Methods: Data on C. auris case demographics, environmental screening, implementation of infection prevention/control measures, and antifungal susceptibility of patient isolates were prospectively recorded then analysed retrospectively. Speciation of C. auris was performed by MALDI-TOF and typing of outbreak isolates performed by amplified fragment length polymorphism (AFLP). Results: This report describes an ongoing outbreak of 50 C. auris cases over the first 16 month (April 2015 to July 2016) within a single Hospital Trust in London. A total of 44 % (n = 22/50) patients developed possible or proven C. auris infection with a candidaemia rate of 18 % (n = 9/50). Environmental sampling showed persistent presence of the yeast around bed space areas. Implementation of strict infection and prevention control measures included: isolation of cases and their contacts, wearing of personal protective clothing by health care workers, screening of patients on affected wards, skin decontamination with chlorhexidine, environmental cleaning with chorine based reagents and hydrogen peroxide vapour. Genotyping with AFLP demonstrated that C. auris isolates from the same geographic region clustered. Conclusion: This ongoing outbreak with genotypically closely related C. auris highlights the importance of appropriate species identification and rapid detection of cases in order to contain hospital acquired transmission
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