129 research outputs found
The impact of the GDPR on German online behavior : an analysis of traffic, cookie compliance and online harms
The European General Data Protection Regulation (GDPR) was implemented in May 2018
to enhance privacy protection. Its implementation has changed the digital landscape and
increased awareness of data privacy rights. This study assesses the impact of the GDPR on
German online traffic. We analyzed traffic data from The Nielson Company for the top 1000
websites in Germany and manually created a dataset to track cookie compliance for these
websites. We find no evidence that German traffic changed. The study used a differencein-differences approach to compare three traffic patterns: (1) changes in German traffic to
websites that show cookie consent notices compared to those that do not; (2) comparison of
German traffic to the United States; and (3) comparison of German traffic inside to outside
the EU. The results showed a decrease in pageviews per person and time per person when
comparing German traffic to the United States. However, statistical analysis did not reveal
a significant difference. The study also found that compliance with the GDPR occurred
gradually over time, with non-compliance being more prevalent among websites with higher
harm scores.O Regulamento Geral Europeu de Protecção de Dados (GDPR) foi implementado em Maio de 2018 para reforçar a protecção da privacidade. A sua implementação alterou o panorama digital e aumentou o conhecimento dos direitos `a privacidade dos dados. Este estudo avalia o impacto do GDPR no tráfego em linha alemão. Analisámos os dados de tráfego da The Nielson Company para os 1000 principais websites na Alemanha e criámos manualmente um conjunto de dados para acompanhar a conformidade dos cookies para estes websites. Não encontramos provas de que o tráfego alemão tenha mudado. O estudo utilizou uma abordagem por diferenças para comparar três padrões de tráfego: (1) alterações no tráfego alemão a websites que mostram avisos de consentimento de cookies em comparação com os que não mostram; (2) comparação do tráfego alemão com os Estados Unidos; e (3) comparação do tráfego alemão dentro para fora da UE. Os resultados mostraram uma diminuição de page views por pessoa e tempo por pessoa ao comparar o tráfego alemão com os Estados Unidos. No entanto, a análise estatística não revelou uma diferença significativa. O estudo concluiu também que o cumprimento do GDPR ocorreu gradualmente ao longo do tempo, sendo o não cumprimento mais prevalecente entre os websites com pontuações de danos mais elevadas
Fremdsprachliches Handeln im Kontext raumtheoretischer Determinanten am Beispiel Street Art
Eine Diskussion um die Bedeutung von Raum für das Erlernen einer fremden Sprache ist zwischen den Polen raumtheoretischer Konstrukte und menschlichen Wahrnehmens und Erlebens zu verorten. Um die eigene Existenz zu erfahren und zu beschreiben, kann die Sprache helfen, Erlebtes zu verbalisieren und sich mit anderen auszutauschen. Sprache wird somit zum Vehikel, welche das Erlebte transportiert und Bedeutungen aushandeln lässt – immer in Abhängigkeit von bestimmten räumlichen und zeitlichen Bezügen. Dieser Artikel greift diese Argumentation auf, indem am Beispiel Street Art als einem Phänomen von ‚Sprache im Raum‘ der benannte Zusammenhang zwischen sprachlichen Handlungen und räumlichen Strukturen dargestellt wird. Es soll aufgezeigt werden, wie die Rezeption von Street Art erzeugten sprachlichen Räumen für diskursive Bedeutungsaushandlungen im Fremdsprachenunterricht genutzt werden kann und Fragen für weitergehende Forschung im skizzierten Spannungsfeld generiert werden.Space is a significant category for explaining human life. Spatial matters influence how individuals participate in human society. As language is an important factor for human discourse, one has to identify how space, action and language influence each other. This article focuses on the relation between space and human discourse. It furthermore argues that language learning can benefit from a spatial view on discourse. It introduces street art as a discursive element of society that depends on spatial aspects and illustrates how foreign language learners can benefit from discussing street art in class
Pro-osteoclastic In Vitro Effect of Polyethylene-like Nanoparticles: Involvement in the Pathogenesis of Implant Aseptic Loosening.
Polyethylene micro-sized wear particles released from orthopaedic implants promote inflammation and osteolysis; however, less is known about the bioactivity of polyethylene nano-sized wear particles released from the last generation of polymer-bearing surfaces. We aim to assess the internalization of fluorescent polyethylene-like nanoparticles by both human macrophages and osteoclasts and also, to determine their effects in osteoclastogenesis in vitro. Human macrophages and osteoclasts were incubated with several ratios of fluorescent polyethylene-like nanoparticles between 1-72 hours, and 4 hours, 2, 4, 6 and 9 days respectively. The internalization of nanoparticles was quantified by flow cytometry and followed by both confocal and video time-lapse microscopy. Osteoclast differentiation and activity was semi-quantified by Tartrate-Resistant Acid Phosphatase (TRAP) staining, TRAP mRNA relative expression and pit resorption assay respectively. Macrophages, osteoclast precursors and mature osteoclasts internalized nanoparticles in a dose- and time-dependent manner and maintained their resorptive activity. In addition, nanoparticles significantly increased the osteoclastogenesis as shown by up-regulation of the TRAP expressing cell number. We conclude that polyethylene-like nano-sized wear particles promote osteoclast differentiation without alteration of bone resorptive activity of mature osteoclasts and they could be considered as important actors in periprosthetic osteolysis of the last new generation of polymer-bearing surfaces. This article is protected by copyright. All rights reserved
Adsorption at cell surface and cellular uptake of silica nanoparticles with different surface chemical functionalizations: impact on cytotoxicity
International audienceSilica nanoparticles are particularly interesting for medical applications because of the high inertness and chemical stability of silica material. However, at the nanoscale their innocuousness must be carefully verified before clinical use. The aim of this study was to investigate the in vitro biological toxicity of silica nanoparticles depending on their surface chemical functionalization. To that purpose, three kinds of 50 nm fluorescent silica-based nanoparticles were synthesized: 1) sterically stabilized silica nanoparticles coated with neutral polyethylene glycol (PEG) molecules, 2) positively charged silica nanoparticles coated with amine groups and 3) negatively charged silica nanoparticles coated with carboxylic acid groups. RAW 264.7 murine macrophages were incubated for 20 hours with each kind of nanoparticles. Their cellular uptake and adsorption at the cell membrane were assessed by a fluorimetric assay and cellular responses were evaluated in terms of cytotoxicity, pro-inflammatory factor production and oxidative stress. Results showed that the highly positive charged nanoparticle, were the most adsorbed at cell surface and triggered more cytotoxicity than other nanoparticles types. To conclude, this study clearly demonstrated that silica nanoparticles surface functionalization represents a key parameter in their cellular uptake and biological toxicity
Effects of Transport Inhibitors on the Cellular Uptake of Carboxylated Polystyrene Nanoparticles in Different Cell Lines
Nanotechnology is expected to play a vital role in the rapidly developing field of nanomedicine, creating innovative solutions and therapies for currently untreatable diseases, and providing new tools for various biomedical applications, such as drug delivery and gene therapy. In order to optimize the efficacy of nanoparticle (NP) delivery to cells, it is necessary to understand the mechanisms by which NPs are internalized by cells, as this will likely determine their ultimate sub-cellular fate and localisation. Here we have used pharmacological inhibitors of some of the major endocytic pathways to investigate nanoparticle uptake mechanisms in a range of representative human cell lines, including HeLa (cervical cancer), A549 (lung carcinoma) and 1321N1 (brain astrocytoma). Chlorpromazine and genistein were used to inhibit clathrin and caveolin mediated endocytosis, respectively. Cytochalasin A and nocodazole were used to inhibit, respectively, the polymerisation of actin and microtubule cytoskeleton. Uptake experiments were performed systematically across the different cell lines, using carboxylated polystyrene NPs of 40 nm and 200 nm diameters, as model NPs of sizes comparable to typical endocytic cargoes. The results clearly indicated that, in all cases and cell types, NPs entered cells via active energy dependent processes. NP uptake in HeLa and 1321N1 cells was strongly affected by actin depolymerisation, while A549 cells showed a stronger inhibition of NP uptake (in comparison to the other cell types) after microtubule disruption and treatment with genistein. A strong reduction of NP uptake was observed after chlorpromazine treatment only in the case of 1321N1 cells. These outcomes suggested that the same NP might exploit different uptake mechanisms to enter different cell types
Adsorption at cell surface and cellular uptake of silica nanoparticles with different surface chemical functionalizations: impact on cytotoxicity
Aufnahmemechanismus und Wirkung chemotherapeutisch beladener Miniemulsions-Nanopartikel in Tumorzellen
The interaction of polymeric nanoparticles (NP) with cells was characterized by flow cytometry, confocal fluorescence and electron microscopy. Extensive studies with different, in detail characterized NP showed in direct comparison that the stabilization and functionalization of 100-250 nm-sized NP but also the polymer type influences the NP uptake.
Biodegradable NP consisting of poly(L-lactide) (PLLA), poly(epsilon-caprolactone) and poly(D,L-lactide-co-glycolide) with non-ionic or anionic stabilization were studied in HeLa and Jurkat cells.
Uptake kinetics of differently stabilized polystyrene (PS) and PLLA NP show that the influence of the surface charge exceeds that of the polymer type. An outstanding uptake augmenting effect of approx. factor 5 is caused by amino functionalization.
In studies with ten different inhibitory drugs, it was shown that the involved endocytotic mechanisms are dependent on the system of NP and the cells. Lipid raft-dependent endocytosis was shown in all systems studied and was often dynamin-dependent. Macropinocytosis was also shown in many systems but clathrin-dependent endocytosis was only detected with aminofunctionalized NP.
A further subproject was establishing a blood brain barrier (BBB) model to check different NP formulations for their ability to pass the BBB. Human brain microvascular endothelial cells were chosen as model cells in a transwell system. Poly(butylcyanoacrylate) NP were tested as potential drug carriers and the results were compared with analogous in vivo studies.
As drug transport is also interesting with regard to tumors beyond the brain, the effect of NP-associated paclitaxel on HeLa and MCF-7 cells was studied. Paclitaxel-containing PS or PLLA NP were effective in HeLa and MCF-7 cells.
This thesis shows that the interaction of NP and cells is dependent on many factors, so there is much potential to optimize NP for different applications
Potenzial der Selbstverstärkung und einer nicht konstanten Getriebekennung zur Verminderung der Leistungs- und Energieaufnahme einer elektromechanischen Radbremse
In der Arbeit werden zwei Wege beschrieben, die zu einer Reduktion der Leistungs- und Energieaufnahme elektromechanisch betätigter Radbremsen führen. Zum einen bietet eine über dem Spannweg veränderliche Getriebeübersetzung z.B. den Vorteil, die geforderte Kraftreserve für den Fadingfall nicht im Motormoment vorzuhalten, sondern in der Getriebeübersetzung. So baut der Motor kleiner und besitzt geringere Massenträgheit, die für eine vergleichbare Dynamik den Leistungsbedarf reduziert. Zum anderen lässt sich die kinetische Energie des fahrenden Fahrzeugs über die Selbstverstärkung nutzen. Für die Bestimmung dieses Potenzials werden die Auslegungsgrenzen der Selbstblockade für herkömmliche hydraulisch betätigte Bremsen überschritten und so Zustände im Betrieb erreicht, bei denen für das Halten einer Spannkraft am Belag gezogen werden muss. Favorisiert wird als Auslegungskriterium die Minimierung der Betätigungskraft, so dass allein aus der zurückgeführten Energie über die Selbstverstärkung während einer Stoppbremsung das benötigte statische Motormoment um zwei Drittel reduziert wird
- …