A new laser refractive procedure is being developed in a rabbit model. With a modified microkeratome, central corneal flaps were created. An ArF excimer laser was used to produce 3-mm-diameter circular ablations on the central part of the exposed stromal bed. One group of animals was sacrificed immediately postoperatively, and both the dissected and ablated areas were studied using scanning electron microscopy. A second group of animals was sacrificed 4 weeks postoperatively. In this group, the subsequent healing of the corneas was studied using light microscopy. At 3 days, the wounded stromal areas showed some degree of haze. Haze was progressively reduced over 1 month, but it could be still discerned biomicroscopically. A hemicircular opacification corresponding to the flap edges was also apparent on slit-lamp examination. Microscopic observation showed that the epithelium was normal, except at the flap margins, where it was thickened. An increased number of keratocytes was observed in the interface between the flap stroma and the ablated area. The procedure might induce stable corneal changes because of the preservation of the anterior layers of the cornea.

Background The COVID-19 pandemic has already changed our globalised world and its long-term impact is not yet known. It is apparent that businesses and institutions are increasingly affected. COVID-19 discussions often focus on intensive care units in hospitals. However, COVID-19 also effects life-saving and-prolonging radiotherapy for patients suffering from cancer. Method We have conducted a structured online survey among medical physicists in Germany, Austria and Switzerland from March 23rd to 26th 2020. In total 154 responses (82 completed, 72 partially completed) were analysed in the context of the COVID-19 dissemination. Results 72.4% of the respondent's state that their processes are affected due to COVID-19, while the top three answers are longer processing times (54.2%), patient no-shows (42.5%) and staff reduction (36.7%). 75.8% expect further unavailability of their personnel in the upcoming weeks. All participants have already taken several measures, especially providing information for patients at the entrance (89.6%) or over the phone (73.6%), restricting access for accompanying persons (77.4%) and providing disinfectant at the entrance (72.6%). Discussion The results presented in this article aim to support business continuity and risk management for radiotherapy centres to prepare for future challenges. The results show that most radiotherapy centres has implemented initial contingency measures, applying them pragmatically. The main problem however remains, that is the high risk of infection both for patients and medical personnel along with the associated risk of temporarily loss of personnel and ordered closure of business.

No abstract

There are several motives for the adoption of 'green' or sustainable materials for car interiors, for example, the shortage of fossil resources and the resulting oilprice increase, new legal requirements (regulations and laws) which penalise environmental pollution and the changing behaviour patterns of consumers. The latter was the subject of an empirical study involving 106 potential car buyers, who were asked about their attitude to sustainable materials in a car interior. Furthermore, consumers' willingness to pay a premium price for a vehicle interior made of renewable resources was also analysed. The main conclusion is that more than 66% of the respondents would accept green car components for a moderate price increase. The relevance and pressure to substitute fossil materials with renewable ones can be expected to increase. This increase will not only be due to the potential decline of resources, but more notably as a result of consumer demand.

Surgery of the stapes may cause a number of complications, including hearing deficits and balance disorders. This has made it necessary to look for improved techniques. Small-fenestra stapedotomy has recently been popularized. Lasers have been advocated for use in fenestrating the stapes footplate. On the other hand, sculpting the middle ear ossicles during tympanoplasty is often necessary for the reconstruction of the ossicular chain and the improvement of sound conduction. Using an excimer laser with a wavelength of 193 nm, fenestrations of the footplate and ossicular sculpting were performed on ossicles obtained during ear surgery and from human cadaver temporal bones. The results indicate that the excimer laser can be used effectively and accurately on an experimental basis and that further research is needed before this method can be used for clinical purposes.

No abstract

Polymers of intrinsic microporosity (PIMs) have promising gas adsorption properties for potential applications such as incorporation into high-pressure hydrogen storage tanks in an effort to increase the storage capacity or decrease the operating pressure. Such applications require detailed mechanical characterisation and determination of the structureproperties relationships to enable optimisation of the interface between the polymer and the container. In this study, we show that Atomic Force Microscopy (AFM) nanoindentation can be used to determine the elastic modulus of cast PIM-1 films and that this property is depthdependent. Average values of elastic modulus obtained experimentally were 1.45 GPa and are compared with elastic tensile modulus and storage tensile modulus obtained in previous studies. In addition, Scanning Electron Microscopy and AFM imaging was performed to investigate the surface structure of the PIM-1 film, which has shown to be highly granular.

No abstract