Search results for " Cleaning"
showing 10 items of 39 documents
Decomposition of nest material in tree holes and nest-boxes occupied by European Starlings Sturnus vulgaris: an experimental study
2017
Numerous bird species depend on the availability of tree cavities, and most non-excavators fill their cavities with considerable amounts of nest material. If not removed, this material can accumulate and render cavities unusable, as recorded in some nest-box studies. Data from earlier studies of tree cavities, however, showed that nest material can decrease mostly due to in situ decomposition, but the relative difference between nest decomposition in tree holes and nest-boxes is still unknown. We undertook parallel studies of decay in tree holes and nest-boxes used by European Starlings Sturnus vulgaris in oak-hornbeam stands (SW Poland). We inserted into its tree holes and nest-boxes litte…
Interradicular Root Canals in Mandibular First Molars: A Literature Review and Ex Vivo Study
2019
Abstract Introduction Successful endodontic treatment vastly depends to a high degree on an accurate knowledge of root canal system morphology. It is a prerequisite to be aware of all possible reservoirs where bacteria and/or toxins can persist, compromising the surrounding tissues; such knowledge results in endodontic success. Methods The presence of interradicular canals and diverticula between the pulp chamber floor and the bifurcation area surface of 117 mandibular first molars was investigated. Access cavities were prepared, the teeth were embedded in plastic, and the pulp chambers were flooded with methylene blue and then centrifuged. An average of 4.2 (0.145 ± 0.03 mm thickness) slic…
What Healthcare Workers Should Know about Environmental Bacterial Contamination in the Intensive Care Unit
2017
Intensive care unit- (ICU-) acquired infections are a major health problem worldwide. Inanimate surfaces and equipment contamination may play a role in cross-transmission of pathogens and subsequent patient colonization or infection. Bacteria contaminate inanimate surfaces and equipment of the patient zone and healthcare area, generating a reservoir of potential pathogens, including multidrug resistant species. Traditional terminal cleaning methods have limitations. Indeed patients who receive a bed from prior patient carrying bacteria are exposed to an increased risk (odds ratio 2.13, 95% confidence intervals 1.62–2.81) of being colonized and potentially infected by the same bacterial spec…
Soft tissue cell adhesion to titanium abutments after different cleaning procedures: preliminary results of a randomized clinical trial
2013
Objectives: A randomized controlled trial was performed to assess soft tissue cell adhesion to implant titanium abutments subjected to different cleaning procedures and test if plasma cleaning can enhance cell adhesion at an early healing time. Study Design: Eighteen patients with osseointegrated and submerged implants were included. Before re-opening, 18 abutments were divided in 3 groups corresponding to different clinical conditions with different cleaning processes: no treatment (G1), laboratory customization and cleaning by steam (G2), cleaning by plasma of Argon (G3). Abutments were removed after 1 week and scanning electron microscopy was used to analyze cell adhesion to the abutment…
Influence of plasma cleaning procedure on the interaction between soft tissue and abutments: a randomized controlled histologic study
2016
Introduction Plasma application can lead to an improved adhesion between soft tissue and abutments and promotes cell spreading. Objective A triple-blinded randomized controlled clinical trial was performed to in vivo test the effect of cleaning abutment titanium surfaces with plasma of argon on cell adhesion and collagen fiber orientation at an early healing time. Material and methods Thirty healthy patients with 30 submerged implants, at the second surgery, randomly received either a specially designed abutment with no additional treatment (as they come from industry; control group, G1) or cleaned by plasma of argon (test group, G2). Two weeks thereafter, a small biopsy including abutment …
Modeling And Measurements Of The Arc Plasma In A Mixture Of Gases
2006
Radial distributions of Ar mass fractions and temperatures in plasmas produced in a wall-stabilized arc have been calculated. Modeling have been performed for many different mixtures of Ar+N2 and three different arc currents. The obtained results show that the radial distributions of Ar mass fractions strongly depend on the chemical composition of the plasma. In plasmas containing large amount of Ar the distributions have local minima at the arc axis (in high temperature plasma regions), whereas in plasmas consisting mainly of nitrogen the distributions reveal maxima on the discharge axis. Those features seem to be connected with the dissociation of the nitrogen.
Study of Inductive Coupled Hydrogen and Argon Plasma Interaction with SiO2 Glass
2009
This work is devoted to the diagnostics of interaction between hydrogen and argon with the surface of SiO2 glass walls. For diagnostics of the interaction, special high-frequency electrodeless light sources were prepared, filled with pure argon of 1 Torr or argon-hydrogen of total pressure of 1 Torr (Ar/H2 mixing ratio is 9:1). Besides the mostly used spherical and cylindrical lamps, dumbbell type lamps have also been investigated. The spectroscopic and AFM measurements showed that in comparison with pure argon plasma, the argon-hydrogen plasma causes non-uniform changes of the SiO2 surface. For these modifications active OH are primarily responsible molecules, created in the reactions of h…
Recent Development on Self-Cleaning Cementitious Coatings
2013
The recent improvements in nano-technologies applied to building coatings are reported, starting from the historical origins of the research on photocatalysis. The description of the main air pollutants and the chemical mechanism of photocatalysis introduce to self-cleaning surfaces and the super-hydrophilic and hydrophobic attitude. Self-cleaning cementitious surfaces, due to nano-structured photocatalysts, mainly titanium dioxide, show environmental benefit in reduction of air pollutants and many experimental evidences are reported together with several applications on building construction. International standards and main spectroscopic techniques aim to evaluate the benefit in terms of …
Evidence for a surface self-cleaning sputtering mechanism in fast atom bombardment mass spectrometry
1985
Evidence for a surface self-cleaning sputtering mechanism in fast atom bombardment mass spectrometry involving significant sputtering from the bulk of the glycerol matrix has been obtained from (a) the time dependence of sample ion abundances and chemical noise for bioorganic compounds, (b) determinations of the sputtering volume in glycerol solution, and (c) studies of in situ chemical and biochemical reactions. The relevance of these results for optimal sample/matrix preparation in analytical applications is pointed out.
Study on the effects of chemical cleaning on pinaceae resin-based varnishes from panel and canvas paintings using pyrolysis-gas chromatography/mass s…
2006
Abstract Cleaning of varnish coatings is one of the most critical steps in the restoration treatment of paintings and characterization of physical and chemical processes involved in this practical procedure has attracted interest of scientists in the field of conservation. Evaluation of chemical cleaning methods based on the application of organic solvents and detergents on Pinaceae resin-based varnishes from panel and canvas paintings has been successfully carried out using pyrolysis-gas chromatograpy/mass spectrometry (Py-GC/MS). The proposed method includes the on-line derivatization of the diterpenoid resin using hexamethyldisilazane (HMDS). Analyses performed on a series of model varni…