Biomedical applications of polypyrrole microactuators : from single-cell clinic to microrobots

Microtools that will be useful for the positioning and investigation microstructures must operate relevant environments, such as cell culture media or blood plasma. They must also be comparatively strong, and preferably allow a muscle like mode of movement. This is given by a novel family of actuators based on conjugated polymers (like polypyrrole, PPy). By miniaturising these structures using standard photolithographic techniques, the authors can reduce the size down to 10-micrometer dimensions and build mechanically active microdevices. These can be moved and positioned by applying a potential to dope or undope the PPy. These novel structures are now being developed as a unique microactuator technology, suitable for operation in applications coupled to cell biology and biomedicin

The cell clinic : closable microvials for single cell studies

We present the development of a cell clinic. This is a micromachined cavity, or microvial, that can be closed with a lid. The lid is activated by two polypyrrole/Au microactuators. Inside the microvials two Au electrodes have been placed in order to perform impedance studies on single or a small number of cells. We report on impedance measurements on Xenopus leavis melanophores. We could measure a change in the impedance upon cell spreading and identify intracellular events such as the aggregation of pigment granules. The electrical data is correlated to optical microscopy.The original publication is available at www.springerlink.com: Edwin WH Jager, Charlotte Immerstrand, Kajsa Holmgren Peterson, Karl-Eric Magnusson, Ingemar Lundström and Olle Inganäs, The cell clinic: Closable microvials for single cell studies, 2002, Biomedical microdevices (Print), (4), 3, 177-187. http://dx.doi.org/10.1023/A:1016092228965 Copyright: Springer Verlag (Germany) http://www.springerlink.com/</p

Importance of sports game elements in movement games for 5-6 year old children

Kvalifikācijas darba temats: Sporta spēļu elementu nozīme kustību rotaļās 5-6 gadus veciem bērniem. Darba izstrādāts ar mērķi pētīt sporta spēļu elementu izmantošanas kustību rotaļās 5-6 gadus veciem bērniem nozīmi. Dotā mērķa sasniegšanai secīgi īstenoti šādi uzdevumi: 1.Analizēt teorētisko literatūru par kustību rotaļām un to pieejamību 5-6 gadus veciem bērniem; 2.Pētīt sporta spēļu elementu iekļaušanas iespējas kustību rotaļās, nosakot piemērotākos elementus 5-6 gadus veciem bērniem; 3.Izstrādāt kritērijus fiziskās un sociālās sfēras attīstības izvērtēšanai un veikt empīrisku pētījumu par sporta spēļu iekļaušanas kustību rotaļās nozīmi 5-6 gadus vecu bērnu fiziskajā un sociālajā attīstībā; 4.Analizēt pētījuma rezultātus un izdarīt secinājumus. Par darba teorētiskās daļas bāzi kalpota tādu zinātnieku atziņas un pētījumi kā A. Fernāte (2008), I.Bula-Biteniece (2013) C. Hillman (2009, 2014), I. Konstantinova (2011), R. Karlovska (2017) u.c. Empīriskajā pētījumā izstrādāti divi kritēriji sociālās attīstības vērtēšanai (izmantota programmā Sociālās un pilsoniskās mācību joma) un divi kritēriji fiziskās aktivitātes izvērtēšanai (izmantota programmā Veselības un fiziskās aktivitātes mācību joma). Pētījums ļauj atklāt, ka pastāv cieša saikne starp bērnu sociālo un fizisko attīstību. Veidojot diferencētu mācību procesu, ir svarīgi noteikt, kura sfēra ir traucēta primāri – sociālā vai fiziskā, attiecīgi izmantojot piemērotus paņēmienus. Sporta spēļu elementu sistemātiska izmantošana atbilst bērnu vajadzībai justies pieaugušam, sacensties, pierādīt savu varēšanu, apgūt jaunas kustību prasmes. Sasniegtie rezultāti ļauj apstiprināt sākotnēji izvirzīto hipotēzi: sporta spēļu elementu iekļaušana kustību rotaļās veiksmīgi sekmē 5-6 gadus vecu bērnu fiziskās un sociālās jomas attīstību. Kvalifikācijas darba apjoms: 55 lpp., 6 attēli, 7 tabulas, 55 literatūras vienības, 2 pielikumiQualification work subject: importance of sports game elements in movement games for 5-6 year old children. To achieve this goal the following tasks have been successively implemented: 1.Analyze theoretical literature of movement games and their accessibility for 5-6 year old children; 2.Explore possibility to include sport games elements in movement games and identifying the most appropriate elements for 5-6 year old children; 3.Draw up criteria to evaluate development of physical and social sphere and do empirical research about significance include sport games in movement games for 5-6 year old children physical and social development; 4.Analyze research results and draw conclusions. The basis of the theoretical part of the thesis is the scientific insights such as A. A. Fernāte (2008), I.Bula-Biteniece (2013) C. Hillman (2009, 2014), I. Konstantinova (2011), R. Karlovska (2017) and others. An empirical study develops two criteria for assessing social development ( was used in the program Social and civic education field) and two criteria for assessing physical activity (was used in the program Health and physical activity education field). The research shows that there is strong connection between children physical and social development. Creating a differentiated learning process it is important to determine which sphere is primarily disturbed – social or physical, and use appropriate techniques. The systematic use of sports game elements responds to the need of children to feel adult, compete, prove your ability, and learn new movement skills. The results obtained confirm the hypothesis: the inclusion of sporting game elements in movement games successfully contributed the physical and social development of 5 - 6 year old children. Keywords: Sports game elements, movement games, senior preschool age, physical, social. Qualification work content: 55 pages, 6 pictures, 7 tables, …. 55 sources of literature were used, 2 appendix adde

Conjugated-polymer micro- and milliactuators for biological applications

The development of new conjugated-polymer tools for the study of the biological realm, and for use in a clinical setting, is reviewed in this article. Conjugated-polymer actuators, based on the changes of volume of the active conjugated polymer during redox transformation, can be used in electrolytes employed in cell-culture media and in biological fluids such as blood, plasma, and urine. Actuators ranging in size from 10 μm to 100 μm suitable for building structures to manipulate single cells are produced with photolithographic techniques. Larger actuators may be used for the manipulation of blood vessels and biological tissue.Original Publication:Charlotte Immerstrand, Kajsa Holmgren Peterson, Karl-Eric Magnusson, Edwin Jager, Magnus Krogh, Mia Skoglund, Anders Selbing and Olle Inganäs, Conjugated-Polymer Micro- and Milliactuators for Biological Applications, 2002, MRS bulletin, (27), 6, 461-464.http://www.mrs.org/s_mrs/sec_subscribe.asp?CID=2959&amp;DID=171856&amp;action=detailCopyright: MRS Materials Research Societyhttp://www.mrs.org/</p