Forced dynamic dewetting of structured surfaces: Influence of surfactants

We analyse the dewetting of printing plates for gravure printing with well-defined gravure cells. The printing plates were mounted on a rotating horizontal cylinder that is half immersed in an aqueous solution of the anionic surfactant sodium 1-decanesulfonate. The gravure plates and the presence of surfactants serve as one example of a real-world dewetting situation. When rotating the cylinder, a liquid meniscus was partially drawn out of the liquid forming a dynamic contact angle at the contact line. The dynamic contact angle is decreased on a structured surface as compared to a smooth one. This is due to contact line pinning at the borders of the gravure cells. Additionally, surfactants tend to decrease the dynamic receding contact angle. We consider the interplay between these two effects. We compare the height differences of the meniscus on the structured and unstructured area as function of dewetting speeds. The height difference increases with increasing dewetting speed. With increasing size of the gravure cells this height difference and the induced changes in the dynamic contact angle increased. By adding surfactant, the height difference and the changes in the contact angle for the same surface decreased. We further note that although the liquid dewets the printing plates some liquid is always left in the gravure cell. At high enough surfactant concentrations or high enough dewetting speed, the dynamic contact angles in the structured surface approach those in flat surfaces. We conclude that surfactant reduces the influence of surface structure on dynamic dewetting

Enrichment of cryoconite hole anaerobes: implications for the subglacial microbiome

Glaciers have recently been recognized as ecosystems, comprised of several distinct habitats: a sunlit and oxygenated glacial surface, glacial ice and a dark, mostly anoxic glacial bed. Surface meltwaters annually flood the subglacial sediments by means of drainage channels. Glacial surfaces host aquatic microhabitats called cryoconite holes, regarded as “hot spots” of microbial abundance and activity, largely contributing to the meltwaters’ bacterial diversity. This study presents an investigation of cryoconite hole anaerobes and discusses their possible impact on subglacial microbial communities, combining 16S rRNA gene fragment amplicon sequencing and the traditional enrichment culture technique. Cryoconite hole sediment harbored bacteria belonging mainly to the Proteobacteria (21%), Bacteroidetes (16%), Actinobacteria (14%) and Planctomycetes (6%) phyla. An 8 week incubation of those sediments in Postgate C medium for sulfate reducers in air tight bottles, emulating subglacial conditions, eliminated a great majority of dominant taxa, leading to enrichment of the Firmicutes (62%), Proteobacteria (14%) and Bacteroidetes (13%), which consisted of anaerobic genera like Clostridium, Psychrosinus, Paludibacter and Acetobacterium. Enrichment of Pseudomonas spp. also occurred, suggesting it played a role as a dominant oxygen scavenger, providing a possible scenario for anaerobic niche establishment in subglacial habitats. To our knowledge this is the first paper to provide insight into the diversity of the anaerobic part of the cryoconite hole microbial community and its potential to contribute to matter turnover in anoxic, subglacial sites

Endoscopic off-pump aortic valve replacement: does the pericardial cuff improve the sutureless closure of left ventricular access?

Objective: Off-pump trans left ventricular approach provides more precise deployment of stented aortic valve of any size with respect to the endovascular replacement. One of the key steps of this procedure is the ventricle repair after catheter withdrawing. We designed an animal study to compare the consistency of a sutureless repair of the left ventricle access using nitinol occluder with and without pericardial cuff on the ventricular side. Methods: Material description: The Amplatz-nitinol occluder consists of two square heads squeezing ventricle wall in between them, sealing the defect. To improve its sealing property, a pericardial patch was sutured to the ventricular head of the occluder. Animal study setup: In adult pigs, a 30F sheath was inserted into the epigastric area through the cardiac apex, up to the left ventricle, simulating the approach for off-pump aortic valve replacement. The sheath was then removed and the ventricle closed with standard occluder in half of the animals, and cuffed occluder in the other half. Animals were followed-up for 3h, collecting haemodynamics data and pericardial bleeding. Results: Device was successfully deployed in 12 animals in less than 1min. In the group where the standard occluder was used, bleeding during the deployment was 80±20ml and after the deployment was 800±20ml over 3h. In the group where the cuffed occluder was used, bleeding during the deployment was 85±20ml and after the deployment was 100±5ml over 3h. In the cuffed group, bleeding was significantly lower than the standard group, p-value being ≪0.001. Conclusions: The occluder is easy to use and the pericardial cuff dramatically increases its efficacy as demonstrated by a significant reduction of blood loss. The cuffed occluder opens the way for endoscopic, off-pump, transventricular aortic valve replacemen

Lepton Polarization Asymmetry in B l l(bar) decays in R-parity violating Minimal Supersymmetric Standard Model

We study the implication of R-parity violating Rp Minimal Supersymmetric Standard Model (MSSM) model in lepton polarization asymmetry ALP in B l l(bar) decays . The analysis show that the ALP is significant in a certain phenomenological parametric region of Yukawa couplings. We have also placed indirect bounds on Lambda' lambda couplings as obtained from B t t(bar).Comment: 6 pages, 4 figures Changes of notation in Eq(8-11,17-19),Eq.20 adde

Does Tolerance Reflect a More Inclusive Self-Construal? A Comparison of Poland, East and West Germany

Past research suggests that Poland and Germany differ in the inclusiveness of their “moral universe”, i.e. the breadth of the community to which people apply moral values and rules of fairness (Schwartz, 2007). It seems likely that this difference is reflected in a more or less inclusive definition of one’s ingroup. The present study investigated (1) whether there are indeed differences in ingroup inclusiveness as manifested in differential construals of the self in East and West Germany and Poland and (2) whether those differences are reflected in differences in tolerance. As expected, participants in West Germany had the most inclusive self-construal, followed by participants from East Germany and then Poland – both in terms of their absolute scores on the most inclusive level (being a member of humanity), and in terms of the relative importance of the different levels. A relationship between a more inclusive self-construal and tolerance was observed in West Germany, but not in East Germany and Poland. The results suggest that more inclusive and abstract levels of the self-construal are more closely linked to other abstract constructs such as values rather than a true reflection of people’s ingroup. In countries with a communist past where universal values or the concern for humanity at large have been used for ideological purposes, these values may have lost their original meaning and psychological significance, and are less linked to intergroup attitudes such as tolerance towards immigrants