Stanisław Flaga

Characteristics of an Experimental MSMA-Based Actuator

Magnetic Shape Memory Alloys (MSMA) constitute one of the newest groups of intelligent materials [. Although these materials have yet to find commercial applications, literature with information on the first pre-prototype actuators can already be found. The mechanism of operation of these actuators is based on the magnetic shape memory effect. During tests, the shifting of piston and current in the coil of the electromagnet were measured. Measurements were synchronized with set courses of this current coil of the actuator. The obtained results made it possible to make static characteristics for constant levels of current, and dynamic curves for constant values of frequency as well as to construct a mathematical model. In this work, the authors have described laboratory tests of an experimental actuator of this type.

Self-reported quality of life in multiple sclerosis patients: preliminary results based on the Polish MS Registry

Background The aim of the study was to analyze selected clinical and sociodemographic factors and their effects on the quality of life (QoL) of multiple sclerosis (MS) patients registered in the Polish MS Registry. Methods This was a cross-sectional observational study performed in Poland. Data on personal and disease-specific factors were collected between January 1, 2011, and December 31, 2015, via the web portal of the Polish MS Registry. All patients were assessed by a physician and asked to complete the Polish language versions of the following self-evaluation questionnaires: EuroQol 5-Dimensions, EuroQoL Visual Analog Scale, and Multiple Sclerosis Impact Scale. Univariate analysis and logistic regression were performed to determine the factors associated with QoL. Results The study included 2,385 patients (female/male ratio 2.3:1) with clinically confirmed MS (mean age 37.8±9.2 years). Average EuroQol 5-Dimensions index was 0.72±0.24, and the mean EuroQoL Visual Analog Scale score was 64.2±22.8. The average Multiple Sclerosis Impact Scale score was 84.6±11.2 (62.2±18.4 for physical condition and 23.8±7.2 for mental condition). Lower QoL scores were significantly associated with higher level of disability (odds ratio [OR], 0.932; 95% confidence interval [CI], 0.876–0.984; P=0.001), age >40 years (OR, 1.042; 95% CI, 0.924–1.158; P=0.012), longer disease duration (OR, 0.482; 95% CI, 0.224–0.998; P=0.042), and lack of disease modifying therapies (OR, 0.024; 95% CI, 0.160–0.835; P=0.024). No significant associations were found between QoL, sex, type of MS course, patient’s education, and marital status. Conclusion The Polish MS Registry is the first national registry for long-term observation that allows for self-evaluation of the QoL. QoL of Polish patients with MS is significantly lower compared with the rest of the population. The parameter is mainly affected by the level of disability, duration of the disease, and limited access to immunomodulatory therapy.

Characteristics of Experimental MSMA-Based Pneumatic Valves

In the course of work on a linear actuator based on a magnetic shape memory alloy (MSMA), a research workstation was constructed enabling the examination of pneumatic valves featuring an electromechanical transducer created with MSMA technology. In this article, the general construction of the research workstation is presented, together with an initial study of a demonstrator of a pneumatic, one-stage, one-way throttle valve. In the presented demonstrator, a simple replacement of a electromechanical transducer into a transducer created with MSMA technology was performed. In addition, the study also describes the problems appearing in such structures along with potential troubleshooting methods.Copyright

Increasing prevalence and incidence of multiple sclerosis in Poland.

Epidemiologic data on multiple sclerosis (MS) in Poland are limited. Our objectives were to assess a mean annual incidence rate, and MS prevalence on December 31, 2015 in the Swietokrzyskie province (central Poland). We analyzed data of 1525 patients, collected in the Polish Multiple Sclerosis Registry. On December 31, 2015, overall crude prevalence of MS was not less than 121.3/100,000 (95% CI, 114.6-128.4). Significantly higher prevalence was recorded in females (167.1; 95% CI, 155.6-179.1) than in males (73.2; 95% CI, 64.2-82.6; P<0.001). The age-adjusted prevalence standardized to the European standard population was 114.2/100,000 (95% CI, 106.2-121.5). The female-male ratio was 2.4:1. The mean annual incidence was 4.5/100,000 (95% CI, 3.8-5.2). Increased MS prevalence and incidence compared to 2010 and previous studies from Poland confirmed that central Poland is a high risk area for MS.

Primary progressive multiple sclerosis in the Polish population

© Medical Communications Sp. z o.o. This is an open-access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDerivatives License (CC BY-NC-ND). Reproduction is permitted for personal, educational, non-commercial use, provided that the original article is in whole, unmodified, and properly cited. Primary progressive multiple sclerosis in the Polish population Pierwotnie postępująca postać stwardnienia rozsianego w populacji polskich pacjentów

Magnetic Shape Memory Alloys Modelling and Pneumatic Applications

Very generally material science could be divided into two groups: scientists who try to invent new materials or improve existing ones and those who work on finding the best applications for the modern materials. Among them there is group named “smart materials” or “active materials”, which have ability to change theirs properties according to the external stimulation. One of the relatively most recent smart material is magnetic shape memory alloy, MSMA in abbreviation. The authors of the article focus on testing samples of this material and try to adapt them to use in fluid devices. The paper mentions about some most interesting valves’ designs equipped with smart materials and summaries the previous MSMA research of the authors. It begins with literature overview of smart material applications in pneumatic or hydraulic valves. There is only one example of MSMA application in valve, therefore the overview concerns mainly the use of piezoelectric, thermal shape memory alloys and giant magnetostrictive materials. Next section describes general properties of the magnetic shape memory alloys and underlines the differences between more widely known Thermal Shape Memory Alloys and MSMA materials. One of the most important property is wide, nonsymmetrical hysteresis in static characteristics of the material, which can be seen as advantage or disadvantage, depending on the application. The material preserves its shape until perpendicular magnetic field or additional force appear. The authors mention about modeling MSMA hysteresis aspect. Three different hysteresis models were briefly described: Generalized Prandtl-Ischlinski, Preisach and Krasnoselskii-Pokrovskii. The last section treats about the current MSMA based valve design concept. It assumes usage of two identical pieces of MSMA materials and energize them oppositely. There is flapper mounted between MSMA samples, which displacement depends on the MSMA elongations. This actuator type is called “push-push” type. Lack of the return spring result in remaining of the flapper in its final position after decreasing of the supply current. The advantage of the solution could be lowering energy consumption of the valve, when the valve setting changes relatively rare during its work. In the future, the presented hysteresis models could improve the work of such MSMA based valve.

Design and Pre-Implementation of Micro-Movements Sensor with Magnetic Shape Memory Material

The paper describe design and built the micro-displacement sensor demonstrator with the use of the active material MSMA. It shows the selection of individual components of the system and its construction. Article presents problems arising during experiments and suggests possible ways of their solution. Shortly characterized other technologies, which are used in commonly used micro-displacement sensors. It also formulated a few comments that may simplify the further development of this project.

Application of Piezoelectric Dynamic Force Sensor for Tool State Assessment in Manufacturing Process

In the paper the problem of examining of a damaged tool in the manufacturing process is presented by the example of the identification of a damaged die for creating a screw drive on a screw head. The operation of the screw head production is known as cold heading. One of the production stage is when a die cuts the head of the screw blank into an appropriate shape. Unfortunately, the die is often damaged before reaching its limit. In this case, the faulty semi-finished products are further processed because the cold heading is only the first operation required to produce a screw. If screws made of high-quality pure stainless steel are considered the economic loss is significant.The measurement automatic systems for identification of damaged dies can be found in the newest machines but they are in minority in comparison to the older ones which work without such systems. It was the reason why attempt was made to construct the prototype diagnostic system for die state assessment, which is presented in the article.Copyright