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Introduction: Parkinson's disease is an idiopathic, slow progressive neurodegenerative condition with the loss of dopaminergic neurons in the substantia nigra compacta of the midbrain. Due to cardiovascular dysautonomia and impaired baroreflex function in Parkinson's disease, the development of orthostatic hypotension is most common, along with increased blood pressure variability, supine hypertension, nocturnal hypertension, etc. Orthostatic hypotension in Parkinson's disease increases the risk of developing coronary heart disease, myocardial infarction, and the risk of overall, and cardiovascular mortality. Case report: Orthostatic hypotension in Parkinson's disease is associated with an increased risk of gait disturbances, loss of balance, falls resulting in injuries and limb fractures, and mortality. In this paper, we presented a patient who had previously been treated for arterial hypertension, with the current clinical presentation of symptomatic orthostatic hypotension in Parkinson's disease. After neurological evaluation and the implementation of pharmacological and non-pharmacological therapy for orthostatic hypotension, gradual improvement and stabilization of blood pressure values are achieved, along with a reduction in orthostatic hypotension symptoms and a decrease in subjective discomfort. Conclusion: In the presence of orthostatic hypotension in Parkinson's disease, in addition to pharmacological therapy, nonpharmacological treatment measures are very important for stabilizing blood pressure values and reducing the symptoms of orthostatic hypotension.

Gear-manufacturing quality affects the load sharing between the meshing gears as well as the load distribution along the width of the tooth. This study aims to investigate the effect of gear-manufacturing quality on the mechanical and thermal states of polymer-gear pairs and consequently on their lifetime. The deviations of the geometric quality parameters, i.e. the lead profile and pitch, were found to have a substantial effect on the stress (root and flank) state of the gear. The effect of the lead deviation was found to be most pronounced for the quality grades Q12 to Q10, where depending on the load, a 30–80% stress reduction was observed when improving the gear quality from Q12 to Q10. Improving the quality from Q10 to Q8 did not lead to a substantial improvement in the load distribution and the observed stress reduction was in range of 5–20%. Similar trends were found for the pitch deviation, where again the most pronounced stress reduction was seen when improving the quality grade from Q12 to Q10. The study reveals where the most effective changes, leading to an increased gear-life, can be achieved. Improving the gear quality grade from Q12 to Q11 proved to have a much more substantial effect than improving the gear quality from Q9 to Q8. Considering that improving the gear quality from Q12 to Q11 or even Q10 can be achieved by a proper tool design and corrective iterations with the right process parameters, while improving the quality from Q9 to Q8 is by far more challenging. A novel methodology is proposed to assess the effect of the gear's quality on the generation of heat and the resulting operational temperature. The proposed methodology enables more accurate prediction of the gear pair's operating temperature. [ABSTRACT FROM AUTHOR]

The market for electric bicycles has grown extremely and developed rapidly in recent years. To enter such a market with a new product, the development process has to be fast, and throughout the process, feedback from future potential customer(s) should be sought in order to achieve the best possible market acceptance. The article presents the design process of a pedelec e-bike central drive system. The authors were members of the development team and the designers of the mechanical transmission, and therefore had a good overview of the whole project. The development process and the set-up of production require a certain amount of time, during which design changes are inevitable due to changes in customer expectations and demands. The development team should respond to these changes and take them into account during development. Only the ability to react to changes and constant communication with the customer will ultimately lead to a product that can be commercially successful. Based on a critical review of the successfully completed project, general guidelines were established for the development of mechatronic products that consider the principles of Agile methodology. Particular attention was paid to the development of polymer gears, as these were the most demanding components in the system. The presented guidelines were based on an overview of the e-bike R&D process presented, but they can be generalized and used in the development process of any technical physical product. Agile methods were developed in the field of software development and therefore cannot be directly transferred to the field of physical product development. The article highlights and discusses individual special features that distinguish agile development of physical products from software development. [ABSTRACT FROM AUTHOR]