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Endothelin-1 (ET-1) is an endogenously expressed potent peptide vasoconstrictor. There is growing evidence that ET-1 plays a role in the pain signaling system and triggers overt nociception in humans. The underlying neuronal pathways are still a matter of great debate. In the present study, we applied an intradermal ET-1 sensitization model to induce mechanical hyperalgesia in healthy subjects. Functional magnetic resonance imaging (fMRI) was used to tease out the cortical regions associated with the processing of ET-1-induced punctate hyperalgesia, as compared to a nonnoxious mechanical stimulation of the contralateral arm. Von Frey hair testing revealed the presence of increased responsiveness to punctate stimulation in all subjects. Activational patterns between nonpainful control stimulation and hyperalgesic stimulation were compared. Two major observations were made: (1) all cortical areas that showed activation during the control stimulation were also present during hyperalgesic stimulation, but in addition, some areas showed bilateral activation only during hyperalgesic stimulation, and (2) some brain areas showed significantly higher signal changes during hyperalgesic stimulation. Our findings suggest that injection of ET-1 leads to a state of punctate hyperalgesia, which in turn causes the activation of multiple brain regions. This indicates that ET-1 activates an extended neuronal pathway. Acclimatisation Intradermal injection of ET-1 Von Frey hair testing Anatomical scout MRI boxcar diagram 10 min 30 min

Two different heat treatments for MDF, microwave assisted pyrolysis (MWP) and conventional pyrolysis (CPS), are investigated. The influence of different microwave absorbers (activated carbon (AC) and K2CO3) and different microwave powers in MWP and different temperatures in CPS on the characteristics of biochar is reviewed. This includes morphology and chemical properties of the obtained biochars are evaluated comparing biochar yield, ultimate analysis, proximate analysis, biochar stability test, FTIR spectroscopy and solid-state 13 C CP/MAS NMR spectroscopy. The resulting biochars of both processes are compared to find the best production method. An increasing microwave power without the use of MWA, leads to a higher degree of aromaticity. The addition of increasing amounts of AC at low microwave power (300 W) leads to higher pyrolysis temperatures and more aromatic biochars. At 400 W a more aromatic biochar with a more open surface is achieved compared to 300 W.However, the addition of an increasing amount of AC as a MWA at 400 W induces a lower pyrolysis temperature with increasing biochar yields and decreasing aromaticity. K2CO3 is more effective as a MWA and produces more aromatic biochar at lower microwave power than when using AC. In general MWP yields a biochar with a higher degree of aromaticity at lower temperatures than CPS. Both CPS and MWP are viable options for transforming MDF into a value added biochar.

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