Silver nano particle formation on Ar plasma : treated cinnamyl alcohol

Metastable induced electron spectroscopy, ultraviolet photoelectron spectroscopy, X-ray photoelectron spectroscopy, and atomic force microscopy are employed to study the adsorption of silver on cinnamyl alcohol films prepared on Au(111) substrates by thermal evaporation. Additionally, the impact of an Ar atmosphere dielectric barrier discharge plasma applied to the cinnamyl alcohol film preliminary to the Ag adsorption is investigated. In both cases silver nano particles with an average diameter of 9 nm are formed. These particles do not interact chemically with the underlying cinnamyl alcohol film. We do not find any influence of the preliminary Ar plasma-treatment on the adsorption behavior at all

Selecting and implementing overview methods: implications from five exemplar overviews

This is the final version of the article. Available from BioMed Central via the DOI in this record.Background Overviews of systematic reviews are an increasingly popular method of evidence synthesis; there is a lack of clear guidance for completing overviews and a number of methodological challenges. At the UK Cochrane Symposium 2016, methodological challenges of five overviews were explored. Using data from these five overviews, practical implications to support methodological decision making of authors writing protocols for future overviews are proposed. Methods Methods, and their justification, from the five exemplar overviews were tabulated and compared with areas of debate identified within current literature. Key methodological challenges and implications for development of overview protocols were generated and synthesised into a list, discussed and refined until there was consensus. Results Methodological features of three Cochrane overviews, one overview of diagnostic test accuracy and one mixed methods overview have been summarised. Methods of selection of reviews and data extraction were similar. Either the AMSTAR or ROBIS tool was used to assess quality of included reviews. The GRADE approach was most commonly used to assess quality of evidence within the reviews. Eight key methodological challenges were identified from the exemplar overviews. There was good agreement between our findings and emerging areas of debate within a recent published synthesis. Implications for development of protocols for future overviews were identified. Conclusions Overviews are a relatively new methodological innovation, and there are currently substantial variations in the methodological approaches used within different overviews. There are considerable methodological challenges for which optimal solutions are not necessarily yet known. Lessons learnt from five exemplar overviews highlight a number of methodological decisions which may be beneficial to consider during the development of an overview protocol.The overview conducted by Pollock [19] was supported by a project grant from the Chief Scientist Office of the Scottish Government. The overview conducted by McClurg [21] was supported by a project grant by the Physiotherapy Research Foundation. The overview by Hunt [22] was supported as part of doctoral programme funding by the National Institute for Health Research (NIHR) Collaboration for Leadership in Applied Health Research and Care South West Peninsula (PenCLAHRC). The overview conducted by Estcourt [20] was supported by an NIHR Cochrane Programme Grant for the Safe and Appropriate Use of Blood Components. The overview conducted by Brunton [23] was commissioned by the Department of Health as part of an ongoing programme of work on health policy research synthesis. Alex Pollock is employed by the Nursing, Midwifery and Allied Health Professions (NMAHP) Research Unit, which is supported by the Chief Scientist Office of the Scottish Government. Pauline Campbell is supported by the Chief Nurses Office of the Scottish Government

Heritable determinants of male fertilization success in the nematode Caenorhabditis elegans

<p>Abstract</p> <p>Background</p> <p>Sperm competition is a driving force in the evolution of male sperm characteristics in many species. In the nematode <it>Caenorhabditis elegans</it>, larger male sperm evolve under experimentally increased sperm competition and larger male sperm outcompete smaller hermaphrodite sperm for fertilization within the hermaphrodite reproductive tract. To further elucidate the relative importance of sperm-related traits that contribute to differential reproductive success among males, we quantified within- and among-strain variation in sperm traits (size, rate of production, number transferred, competitive ability) for seven male genetic backgrounds known previously to differ with respect to some sperm traits. We also quantified male mating ability in assays for rates of courtship and successful copulation, and then assessed the roles of these pre- and post-mating traits in first- and second-male fertilization success.</p> <p>Results</p> <p>We document significant variation in courtship ability, mating ability, sperm size and sperm production rate. Sperm size and production rate were strong indicators of early fertilization success for males that mated second, but male genetic backgrounds conferring faster sperm production make smaller sperm, despite virgin males of all genetic backgrounds transferring indistinguishable numbers of sperm to mating partners.</p> <p>Conclusions</p> <p>We have demonstrated that sperm size and the rate of sperm production represent dominant factors in determining male fertilization success and that <it>C. elegans </it>harbors substantial heritable variation for traits contributing to male reproductive success. <it>C. elegans </it>provides a powerful, tractable system for studying sexual selection and for dissecting the genetic basis and evolution of reproduction-related traits.</p

The Current Practice of Gradual Return to Work in Germany: A Qualitative Study Protocol

(1) Background: The increase in working age and long-term illnesses is a challenge for society to maintain the health of employees and to support their work participation. In many countries, such as Germany, a gradual return to work (GRTW) is used frequently to support returning employees, but little is known about its facilitators and obstacles. This protocol aims to provide an overview of the national state of the art in workplace adjustments during return to work and to outline the design of a qualitative study examining current GRTW practices in Germany. (2) Methods: Our qualitative study will examine the current implementation of GRTW by means of 32 narrative interviews and 10 group discussions from different perspectives. Therefore, we will ask returning employees as well as organisational stakeholders and external experts about their experiences with GRTW and attitudes towards the measure. The verbal data obtained will be analysed using the documentary method of interpretation. (3) Discussion: This study will reveal facilitating and hindering factors for the implementation of GRTW in Germany. The findings of the study may contribute to an improved implementation of GRTW not only in Germany

Tvorba srebrovih nanodelcev na ligninu in njegovih dveh prekurzorjih

Metastable Induced Electron Spectroscopy, Ultraviolet Photoelectron Spectroscopy (He I and He II), X-ray Photoelectron Spectroscopy, and Atomic Force Microscopy were employed to study the interaction of silver with lignin as well as with two of its natural precursors, coniferyl alcohol and sinapyl alcohol. For all three of them, no chemical interaction between the adsorbed silver and the organic substrate was found before contact with air. Nevertheless, silver nanoparticles were found in all three cases after contact with air. Thus, a process of silver nanoparticle formation during the decomposition of the organic molecules is suggested, similar to the previously found catalytic decomposition of cinnamyl alcohol by water in the presence of silver atoms.Za preučevanje interakcije srebra z ligninom ter z njegovima naravnima prekurzorjema koniferil alkoholom in sinapil alkoholom smo uporabili metastabilno elektronsko spektroskopijo, ultravijolično fotoelektronsko spektroskopijo (He I in He II), rentgensko fotoelektronsko spektroskopijo in mikroskopijo na atomsko silo. V vseh treh primerih nismo ugotovili kemijske interakcije med adsorbiranim srebrom in organskim substratom. Kljub temu pa smo v vseh treh primerih po stiku z zrakom detektirali nanodelce srebra. Na podlagi teh opažanj smo predlagali proces tvorbe srebrovih nanodelcev med razgradnjo organskih snovi, ki je podoben predhodno ugotovljenemu katalitskemu razkroju cinamil alkohola z vodo v prisotnosti atomov srebra

Polymer-induced metal diffusion during plastic processing: A reason for deposit formation

In the plastic-processing industry, the formation of unknown deposits at the interface between polymer melt and steel surfaces can pose major challenges, which occurs especially on screws, barrels, and tools. These deposits will detach during production and lead to quality restrictions mostly as spots in the products. We investigated the interactions between tool steel and polymer melt, especially polycarbonate, in the early stages of deposit formation. Steel-polymer-composite samples are prepared close to the realistic conditions in the plastic-processing industry. To get further insight, thin polymer films on tool steel specimens and its alloy elements, representing model systems, are prepared. X-ray-photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES) are used to characterize the interfaces chemically. Additionally, atomic force microscopy (AFM) and scanning electron microscopy (SEM) were used. We found iron and chromium diffusion into the polycarbonate melt induced by polymer metal interaction. Iron and polymer chains are immobilized at the interface by a chemical interaction, while chromium does not chemically interact with the polymer melt. Basing on these results, we propose a mechanism for deposit formation in plastic-processing machines and tools