Application of high-speed camera measurements for determination of energy losses generated in a vibrating belt of CVT transmission

The paper presents a proposition of the theoretical-experimental method of determination of power losses in the transversely vibrating rubber V-belt of continuously variable transmission. The article comprises the results of experimental tests conducted on a special test stand with a complete scooter drivetrain powered by a small two-stroke internal combustion engine. Such a configuration allows ensuring real CVT working conditions. A high-speed camera was used for the contactless measurement of belt vibrations and time-lapse image analysis was performed in dedicated software. An axially moving Euler–Bernoulli beam was assumed as the mathematical model. Longitudinal vibrations and nonlinear effects were omitted. Additionally, it was assumed that the belt material behaves according to the Kelvin–Voigt rheological model. Analysis of the damped free vibrations of the cantilever beam, made of the belt segment, allowed to determine the equivalent bending damping coefficient. The CVT power losses, due to bending in the rubber transmission belt, were obtained for the fixed working conditions after numerical calculations. The proposed methodology is a new approach in this research area, which allows to obtain results impossible to achieve with other measurement methods

Protokół terapeutyczny w dokumentowaniu procesu napromieniania pacjentów w zakładzie radioterapii

SummaryA decision to start radiotherapy should be based on at least two documents:1.Written standards of obligatory clinical procedures which are in fact radiotherapeutic schemes.2.Therapeutic protocols describing all mandatory procedures performed to ensure a safe and proper treatment of the patient.The range of activities described in the therapeutic protocol is very wide.It includes all initial procedures implemented in the simulation room, the CT scanner, in the treatment planning system and the mould- room, and it describes the verification process of the treatment plan, mandatory to start radiotherapy.The therapeutic protocol describes in details what and how should be checked by an internal control system and it qualifies the demands required to sum up the treatment and its’ accordance with the planned radiotherapy scheme.All the activities performed are recorded in a QA protocol, which is an integral part of the therapeutic protocol.In this paper we present the therapeutic protocol in force in the Regional Oncological Hospital in Szczecin and the QA and in-vivo protocols, which assure safe radiotherapy of the patient

A radiotherapy protocol to document the process of irradiation of patients at the radiotherapy department

A decision to start radiotherapy should be based on at least two documents:1.Written standards of obligatory clinical procedures which are in fact radiotherapeutic schemes.2.Therapeutic protocols describing all mandatory procedures performed to ensure a safe and proper treatment of the patient.The range of activities described in the therapeutic protocol is very wide.It includes all initial procedures implemented in the simulation room, the CT scanner, in the treatment planning system and the mould- room, and it describes the verification process of the treatment plan, mandatory to start radiotherapy.The therapeutic protocol describes in details what and how should be checked by an internal control system and it qualifies the demands required to sum up the treatment and its’ accordance with the planned radiotherapy scheme.All the activities performed are recorded in a QA protocol, which is an integral part of the therapeutic protocol.In this paper we present the therapeutic protocol in force in the Regional Oncological Hospital in Szczecin and the QA and in-vivo protocols, which assure safe radiotherapy of the patient

Effects of juglone and lawsone on oxidative stress in maize coleoptile cells treated with IAA

Naphthoquinones are secondary metabolites widely distributed in nature and produced by bacteria, fungi and higher plants. Their biological activity may result from induction of oxidative stress, caused by redox cycling or direct interaction with cellular macromolecules, in which quinones act as electrophiles. The redox homeostasis is known as one of factors involved in auxin-mediated plant growth regulation. To date, however, little is known about the crosstalk between reactive oxygen species (ROS) produced by quinones and the plant growth hormone auxin (IAA). In this study, redox cycling properties of two naphthoquinones, juglone (5-hydroxy-1,4-naphthoquinone) and lawsone (2-hydroxy-1,4-naphthoquinone), were compared in experiments performed on maize coleoptile segments incubated with or without the addition of IAA. It was found that lawsone was much more effective than juglone in increasing both H2O2 production and the activity of antioxidative enzymes (SOD, POX and CAT) in coleoptile cells, regardless of the presence of IAA. An increase in the activity of Cu/Zn-SOD isoenzymes induced by both naphthoquinones suggests that juglone- and lawsone-generated H2O2 was primarily produced in the cytosolic and cell wall spaces. The cell potential to neutralize hydrogen peroxide, determined by POX and CAT activity, pointed to activity of catalase as the main enzymatic mechanism responsible for degradation of H2O2. Therefore, we assumed that generation of H2O2, induced more efficiently by LW than JG, was the major factor accounting for differences in the toxicity of naphthoquinones in maize coleoptiles. The role of auxin in the process appeared negligible. Moreover, the results suggested that oxidative stress imposed by JG and LW was one of mechanisms of allelopathic action of the studied quinones in plants