Phase Change Material for Thermotherapy of Buruli Ulcer: A Prospective Observational Single Centre Proof-of-Principle Trial

Buruli ulcer is an infection of the subcutaneous tissue leading to chronic necrotizing skin ulcers. The causative pathogen, Mycobacterium ulcerans, grows best at 30°C–33°C and not above 37°C, and this property makes the application of heat a treatment option. We achieved a breakthrough in heat treatment of Buruli ulcer by employing the phase change material sodium acetate trihydrate as a heat application system for thermotherapy, which is widely used in commercial pocket heat pads. It is easy to apply, rechargeable in hot water, non-toxic and non-hazardous to the environment. Six laboratory reconfirmed patients with ulcerative Buruli lesions were included in the proof-of-principle study and treated for four to six weeks. In patients with small ulcers, wounds healed completely without further intervention. Patients with large defects had skin grafting after successful heat treatment. Heat treatment was not associated with marked increases in local inflammation or the development of ectopic lymphoid tissue. One and a half years after completion of treatment, all patients are relapse-free. The reusable phase change material–based heat application device appears perfectly suited for use in remote Buruli ulcer–endemic areas of countries with limited resources and infrastructure

Phase change material for thermotherapy of Buruli ulcer : modelling as an aid to implementation

A mathematical model was developed and validated to predict the thermal behaviour of a heat application device based on a phase change material (pcm) for the heat treatment of Mycobacterium ulcerans infection (Buruli ulcer). The thermal model allows the prediction of skin surface temperatures and an optimization of the amount of pcm with respect to discharge time. A first prototype of such a pcm bandage was manufactured and used in a proof-of-principal trial in Cameroon. The experimental data were analysed and yielded no difference in thermoregulatory response between people living in hot or moderate climate. Short-term maximum skin surface temperatures of 42 degrees C are tolerable; the pcm bandage keeps the skin surface temperature above 40 degrees C for about four to five hours. This makes such pcm bandages an ideal device for the heat treatment of Buruli ulcer. The pcm bandage is easy to apply, cheap, and thus is well suited for use in low-resource countrie

Kuehlkreislauf mit passiver Kaelteerzeugung durch Strahlungskuehlung Abschlussbericht

The concept of passive cooling by radiative, convective and evaporative heat transfer has proved to be successful and should be tested in further plants. Low-cost but reliable components should be selected, as well as efficient pumps. Synergy effects should be use, e.g. cold storage combined with service water storage, use of existing water stores, etc. The efficiency of passive cooling increases with the cooling water temperature. Apart from office buildings, also technical facilities and machines could be cooled by this process, which is applicable in all cases where waste heat must be cooled but the temperature can be clearly higher than 20 C. (orig.)Das Konzept der passiven Kuehlung durch Strahlung, Konvektion und Verdunstung hat sich bewaehrt. Es sollte in weiteren Anlagen getestet werden. Dabei sollte auf kostenguenstige, aber solide Anlagentechnik geachtet werden. Zur Optimierung der Gueteziffer sollten Pumpen mit gutem Wirkungsgrad eingesetzt werden. Zu untersuchen waere, welche Gueteziffern mit Tauchpumpen in der Zisterne zu erreichen sind. Um die Investitionskosten zu senken, sollten Synergieeffekte genutzt werden: z.B. Nutzung der Zisterne als Kaeltespeicher und als Grauwasserspeicher, Nutzung von vorhandenen Wasserspeichern (Feuerloeschteiche, Sprinkleranlagen,...). Die passive Kuehlung ist um so effizienter, je hoeher die Temperatur des Kuehlwassers sein darf. Daher sollte nicht nur an (Buero-)Gebaeudekuehlung gedacht werden. Technische Anlagen und Maschinen, bei denen Abwaerme weggekuehlt werden muss, die Temperatur aber deutlich ueber 20 C sein darf, koennten sehr effektiv gefuehlt werden. (orig.)SIGLEAvailable from TIB Hannover: F04B525 / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDeutsche Bundesstiftung Umwelt, Osnabrueck (Germany)DEGerman

Upgrading the beam telescopes at the DESY II Test Beam Facility

The DESY II Test Beam Facility is a key infrastructure for modern high energy physics detector development, providing particles with a small momentum spread in a range from 1 to 6GeV to user groups e.g. from the LHC experiments and Belle II as well as generic detector R&D. Beam telescopes are provided in all three test beam areas as precise tracking reference without time stamping, with triggered readout and a readout time of > 115 μs . If the highest available rates are used, multiple particles are traversing the telescopes within one readout frame, thus creating ambiguities that cannot be resolved without additional timing layers. Several upgrades are currently investigated and tested: Firstly, a fast monolithic pixel sensor, the TELEPIX, to provide precise track timing and triggering on a region of interest is proposed to overcome this limitation. The TELEPIX is a 180nm HV-CMOS sensor that has been developed jointly by DESY, KIT and the University of Heidelberg and designed at KIT. In this publication, the performance evaluation is presented: The difference between two amplifier designs is evaluated. A high hit detection efficiency of above 99.9% combined with a time resolution of below 4ns at negligible pixel noise rates is determined. Finally, the digital hit output to provide region of interest triggering is evaluated and shows a short absolute delay with respect to a traditional trigger scintillator as well as an excellent time resolution. Secondly, a fast LGAD plane has been proposed to provide a time resolution of a few 10 ps, which is foreseen to drastically improve the timing performance of the telescope. Time resolutions of below 70 ps have been determined in collaboration with the University of California, Santa Barbara

Upgrading the beam telescopes at the DESY II Test Beam Facility

The DESY II Test Beam Facility is a key infrastructure for modern high energy physics detector development, providing particles with a small momentum spread in a range from 1 to 6GeV to user groups e.g. from the LHC experiments and Belle II as well as generic detector R&D. Beam telescopes are provided in all three test beam areas as precise tracking reference without time stamping, with triggered readout and a readout time of > 115 μs . If the highest available rates are used, multiple particles are traversing the telescopes within one readout frame, thus creating ambiguities that cannot be resolved without additional timing layers. Several upgrades are currently investigated and tested: Firstly, a fast monolithic pixel sensor, the TELEPIX, to provide precise track timing and triggering on a region of interest is proposed to overcome this limitation. The TELEPIX is a 180nm HV-CMOS sensor that has been developed jointly by DESY, KIT and the University of Heidelberg and designed at KIT. In this publication, the performance evaluation is presented: The difference between two amplifier designs is evaluated. A high hit detection efficiency of above 99.9% combined with a time resolution of below 4ns at negligible pixel noise rates is determined. Finally, the digital hit output to provide region of interest triggering is evaluated and shows a short absolute delay with respect to a traditional trigger scintillator as well as an excellent time resolution. Secondly, a fast LGAD plane has been proposed to provide a time resolution of a few 10 ps, which is foreseen to drastically improve the timing performance of the telescope. Time resolutions of below 70 ps have been determined in collaboration with the University of California, Santa Barbara