Search

We developed a fabrication procedure for thin glass cells containing lyotropic liquid crystalline materials. Liquid crystalline displays are widely used in everyday life but there is still a lot of space for improvements. One possibility is to use lyotropic liquid crystals, which are highly sensible not only to temperature and electric fields but also to concentration variations, thus giving them an additional parameter for fine-tuning. We used the DNA sequence d(G4C2) as a model lyotropic system. In order to study its liquid crystalline behaviour we had to develop a new procedure for fabricating LC cells to contain our materials, since commercially available cells were unsuitable. Herein we present the optimized fabrication method for such lyotropic LC cells. [ABSTRACT FROM AUTHOR]

Generally, noise is a considerable stress factor in several workplaces and living environments. Despite legal regulations and recommendations, there are still many problems resulting from noise exposure, especially extra-aural effects. We studied the influence of noise on workers in two different environments: A Technical High School and a manufacturing company. Measurements of noise levels were performed, together with corresponding noise frequency analysis. In both cases, working places were found where the noise levels exceeded the upper exposure level of 85 dB (A). In comparison to measurements, personal noise perceptions of workers were assessed by an extended research survey. Correlating the survey's results and experimentally determined noise levels gave us new insights into the occupational health risks of noise in two very different working environments. [ABSTRACT FROM AUTHOR]

Background: The aim of our study was to prospectively evaluate the effectiveness of the Fistula Laser Closure (FiLaC®) technique in patients at high risk of anal incontinence and to determine the predictors of success and the impact of the procedure on anal continence. Methods: A prospective study was conducted on all patients treated with FiLaC® in our department in May 2016–April 2017, because they were at high risk of anal incontinence after fistulotomy, The fistula was considered healed when the internal and external openings were closed and the patient experienced was no pain or leakage. Results: A total of 69 consecutive patients (34 males) with a median age of 40 years (33–53 years) were included in the study. One patient was lost to follow up. The fistulas were intersphincteric (3%), low (15%) or high (66%) trans-sphincteric, and suprasphincteric (16%). After a median follow-up period of 6.3 months (4.2–9.3), fistula healing was observed in 31 patients (45.6%). In univariate analysis, high trans-sphincteric fistulas (p = 0.007) and age over 50 years (p = 0.034) were significantly associated with healing. In multivariate analysis, only high trans-sphincteric fistulas were a predictive factor of significant success. No new cases of anal incontinence or any worsening in case of pre-existing anal incontinence were observed during follow-up. Conclusions: FiLaC® is particularly effective in cases of high trans-sphincteric fistulas (60% cure). This technique seems to be the most promising sphincter-saving technique available for this indication. [ABSTRACT FROM AUTHOR]

Self-assembling and dynamical properties of deoxyguanosine 5’-monophosphate in isotropic aqueous solutions were studied by 31P NMR spectroscopy and dynamic light scattering (DLS). All solutions had the same c = 4 wt% guanosine concentration, while the added KCl molarity ranged from 0 to 1.5 M. 31P NMR measurements show that potassium ions strongly enhance the stacking process of guanosine tetramers until a saturation is reached at 0.1 M KCl with more than 70% of the molecules aggregated. Polarized light scattering reveals the presence of a fast relaxation mode that arises from the translational dynamics of the self-assembled stacks. The diffusion coefficient of this mode shows a strong dependence on molarity of added salt, which can be described in terms of the coupled mode and counterion condensation theories for polyelectrolyte solutions. Depolarized light scattering reveals the rotational dynamics of the self-assembled stacks which exhibits a pronounced slowing down with increasing the added salt content. [ABSTRACT FROM AUTHOR]