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Poliuretansko peno lahko poleg lepljenja spajamo tudi z varjenjem z vročim zrakom. Za uspešno varjenje z vročim zrakom potrebujemo ustrezno napravo za varjenje, ki omogoča natančno varjenje in dobro ponovljivost procesa. Poleg naprave za varjenje potrebujemo tudi optimalne parametre varjenja, ki zagotavljajo dovolj velik vnos toplote v cono varjenja. V diplomski nalogi je predstavljena poliuretanska pena in njene glavne lastnosti. Predstavljena je naprava za varjenje in njeni sestavni deli ter optimalni parametri varjenja. Optimalne parametre smo določili s poskušanjem. Izveden je bil ročni natezni preizkus in mikroskopska analiza zvarnih spojev. Na osnovi rezultatov smo določili okno procesnih parametrov, ki omogočajo uspešno varjenje poliuretanske pene. In addition to adhesive bonding, polyurethane foams can also be joined by hot air welding. For successful hot air welding, we need appropriate welding apparatus that enables accurate welding and good reproducibility of the process. In addition to preparation for welding, we also need optimal welding parameters that ensure sufficient heat input into the welding zone. The thesis presents polyurethane foam and its main properties. The apparatus for welding and its components as well as the optimal welding parameters are presented. The optimal parameters were determined using a trial and error approach. A manual tensile test and a microscopic analysis of the welds were performed. Based on the results, we determined a window of process parameters that enable successful welding of polyurethane foams.

Background Due to infection of chronic wounds with antibiotic resistant bacterial strains, their healing can be very difficult. The main purpose of the presented research study was the introduction of a new method for chronic wounds healing, using Lucilia sericata fly larvae into Slovenia. Methods For chronic wound healing sterile larvae of L. sericata fly were prepared from a continuous fly culture, maintained at the Department of Biology, Biotechnical Faculty, University of Ljubljana. In this way 32 wounds of 30 patients were treated. Larvae were applied on the wounds for two to three days. Than they were washed off and replaced, if necessary. Microbiological smears were collected before and after the application of the larvae on the wounds. Microorganisms were then isolated and identified. During larval therapy healing improvement, patientćs general state, potential presence of pain, mobility, patientćs independence and psychological reaction to the therapy were monitored. Results Using biosurgical therapy 24 (75%) out of 32 wounds were cleaned and healed. In the case of combined arterio-venous leg ulcers onewound was completely healed and eight of them were cleaned of necrosis and infection. In the case of a venous leg ulcer, six diabetic ulcers, eight casesof chronic postoperative wounds and pressure ulcers, wounds were completely cleaned after the treatment. 16 patients reported unpleasant feeling during larval treatment and two patients felt pain which diminished after the treatment with analgesics. 17 (57%) patients had to use crutches during biosurgical treatment and the same number of patients felt uncomfortable, frightened and depressed during the application of larvae. Izhodišča Ker so kronične rane danes pogosto okužene z bakterijskimi sevi, odpornimi na antibiotike, je njihovo zdravljenje težavno. Namen raziskovalnega projekta je bil uvesti v Slovenijo novo metodo zdravljenja kroničnih ran z uporabo ličink muh Lucilia sericata. Metode Za zdravljenje kroničnih ran smo uporabili sterilne larve L. sericata, pridobljene v kontinuirani kulturi na Oddelku za biologijo Biotehniske fakultete UL. Na ta način smo zdravili 32 ran pri 30 bolnikih. Ličinke smo na rani pustili delovati dva do tri dnič nato smo jih odstranili in po potrebi ponovno namestili. Pred namestitvijo in po njej smo jemali mikrobiološke brise tkiva vrani in iz njih osamili ter identificirali bakterijske vrste. Med biokirurskim zdravljenjem smo spremljali potek zdravljenja, bolnikovo počutje, morebitne bolečine, pokretnost, samostojnost in psiholoski odziv ob terapiji. Rezultati Z biokirurskim zdravljenjem smo uspeli zaceliti in očistiti 24 ran od 32 (75%). V primeru kombinirane arterijsko-venske razjede smo uspeli popolnoma zaceliti eno rano in očistiti 8 ran, v primeru venske razjede na nogi in sestih diabetičnih razjed so se vse rane očistile. V primerih preležanin in pooperativnih kroničnih ran smo z biokirurgijo vse ranev celoti očistili. 16 bolnikov je med nosenjem ličink občutilo neprijeten občutek, pri dveh so se pojavile bolečine, ki so se po dodatku analgetikov pomirile. Med zdravljenjem si je pri hoji z berglami pomagalo 17 (57%) bolnikov. Ugotovili smo, da je 17 bolnikov (57%) čutilo strah in depresijo ter nelagoden občutek. Zaključki Metoda zdravljenja z ličinkami muhe L. sericata je bila uspešno uvedena v Slovenijo. Zaradi enostavnosti in uspešnosti bi jo bilo potrebno kot način zdravljenja uvesti tudi v vsakdanjo slovensko klinično prakso. Z biokirurgijo se kronične rane hitreje celijo, preprečimo nadaljnja vnetja in propadanje tkiva ter bolniku omogočimo normalno vključevanje v vsakdanje življenje.