Green roofs are increasingly popular in both new and modernised buildings. They significantly reduce the outflow of stormwater from buildings and change its composition. Wherever an urbanised area is equipped with a separate sewage system, usually stormwater goes directly to the receiver without treatment, which may affect the quality of water in the receiver. The article presents results of research carried out on the green roof of a building in Lodz, Poland. During rainfall, the flow rate from the roof was measured. With the use of the US EPA software Stormwater Management Model (SWMM) a model of the green roof was created and calibrated using rainfall data from the city’s pluviometric network. Based on the measurements of the roof runoff, as well as SWMM modelling, the degree of outfall reduction was determined. Samples of roof runoff were collected to study the characteristics of rainwater, including pH, electrical conductivity, organic compounds, nitrogen, phosphorus, and suspended solids. The results were compared with the quality of runoff from a traditional roof. Except ammonium nitrogen, values of the examined quality indicators was higher in the case of the green roof but the pollution load of almost all contaminants, except phosphorus, were lower due to a significant reduction in the volume of stormwater outflow (62–91%). The quality of stormwater discharged from the green roof improved with its age.

Peri-implantitis is a pathological condition occurring in tissues around dental implants, characterized by inflammation in the peri-implant connective tissue and progressive loss of supporting bone. In the treatment of peri-implantitis, a laser surgical technique is used. Lasers are a safe and gentle alternative to traditional dental tools. They allow oral surgeons and dentists to accomplish more complex tasks, reduce blood loss, decrease post-operative discomfort, reduce the chance of wound infection, achieve better wound healing and perform some procedures in close methods without access flap. The aim of the work was to determine the impact of laser surface treatment of titanium dental implants on its electrochemical behavior in artificial saliva at 37°C. The study used an Er,Cr:YSGG laser and diode lasers 810 nm and 980 nm for debridement of titanium implant surface. In the research, the thread on the surface of implant was scanned with the diode laser beam of energy 1, 1.25, 1.5 and 2 W, cw and Er, Cr YSGG: 1,5 and 2W, pulse 30Hz.

Background: At the Department of Medical Education, Centre for Innovative Medical Education at Jagiellonian University Medical College, a completely remote OSCE (e-OSCE) was con-ducted for the first time using the Microsoft Teams platform. 255 test takers were tasked with presenting their communication and clinical skills in order to assess clinical reasoning.
Aim: Analysis of the assessment of the OSCE adaptation to the requirements of the COVID-19 pandemic at the Department of Medical Educations in the form of the e-OSCE from the students’ perspective.
Methods: Discussion of the OSCE modification was carried out among 6th-year medical students and graduates undergoing validation of their foreign medical degrees. In order to assess students’ opinions of the e-OSCE, we used questionnaires. The Statistica 12.0 program was used to analyse the results.
Results: According to 91.57% of respondents, the e-OSCE was well-prepared. 60% of students strongly agree and 29.47% rather agree that the order of the stations was appropriate and clear. A majority of respondents rated the e-OSCE as fair. 66.32% of respondents strongly agree and rather agree that the proportions of communication and clinical skills were appropriate. The vast majority of the participants of the exam (81.05%) had enough time for individual stations. A statistically significant (p <0.0001) correla-tion was found between the type of classes and preparation for the e-OSCE. For 61.05% of respondents, the Laboratory Training of Clinical Skills course was the best preparation for students taking the e-OSCE. Taking into account the stressfulness of the OSCE, only 15.96% of students found the online form more stressful than the traditional (in-person) exam.
Conclusions: The e-OSCE in students’ opinions was well-organized. Informing test-takers prior to the e-OSCE about the role of invigilators assessing individual stations should be improved. The e-OSCE has been proven to be suitable for assessing a wide range of material and validating communication and clinical skills in appropriate proportions. The e-OSCE is fair according to examinees’ opinion. The study proves that even in a pandemic, it is possible to prepare an online exam without exposing examiners and examinees to the dangers posed by COVID-19.

Large elongation in one de?nite direction of a crystal of cubic symmetry is considered. The equations of second order elasticity theory are applied. In this approximation three constants of the second order and six constants of the third order characterize the crystal. The stress is a function of the elongation direction. The elongation directions for which the stress reaches an extreme value have been analyzed.