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Insufficient hemodynamics during agonal phase—ie, the period between withdrawal of life‐sustaining treatment and circulatory arrest—in Maastricht category IIIcirculatory‐death donors (DCD) potentially exacerbate ischemia/reperfusion injury. We included 409 Dutch adult recipients of DCDdonor kidneys transplanted between 2006 and 2014. Peripheral oxygen saturation (SpO2‐with pulse oximetry at the fingertip) and systolic blood pressure (SBP‐with arterial catheter) were measured during agonal phase, and were dichotomized into minutes of SpO2 > 60% or SpO2 < 60%, and minutes of SBP> 80 mmHg or SBP< 80 mmHg. Outcome measures were andprimary non‐function (PNF), delayed graft function (DGF), and three‐year graft survival. Primary non‐function (PNF) rate was 6.6%, delayed graft function (DGF) rate was 67%, and graft survival at three years was 76%. Longer periods of agonal phase (median 16 min [IQR11‐23]) contributed significantly to an increased risk of DGF(P= .012), but not to PNF(P= .071) and graft failure (P= .528). Multiple logistic regression analysis showed that an increase from 7 to 20 minutes in period of SBP< 80 mmHg was associated with 2.19 times the odds (95% CI1.08‐4.46, P= .030) for DGF. In conclusion, duration of agonal phase is associated with early transplant outcome. SBP< 80 mmHg during agonal phase shows a better discrimination for transplant outcome than SpO2 < 60% does. This investigation of the predictive ability of hemodynamics during the agonal phase of circulatory death donors shows that systolic blood pressure discriminates short‐term transplant outcomes better than peripheral oxygenation does.

Abstract: The crosslinking of alkyd resins has been studied using ethyl linoleate and methyl ricinoate as model compounds. With quantitative13C NMR it was established that ether- and peroxy-crosslinks were formed in roughly equal amounts. Double bonds reacted to give epoxides, endoperoxides, and β-scission into aldehydes. Using SIMS it was established that dimers through pentamers were formed having included several oxygen atoms. After reduction of peroxide (crosslinks) with stannous chloride, the higher oxygen homologues decreased. In the NMR spectrum of the reduced material, peroxide and epoxide signals completely disappeared. High resolution electrospray ionization mass spectra (ESI-MS) yielded evidence regarding the crosslink mechanism. The non-conjugated linoleic acid was found to crosslink by combination of radicals: dimers were having masses 2(M-1). The conjugated linoleic acid crosslinked by addition of radicals to the double bond and disproportionation, yielding masses 2M as well. (M = mass of ethyl linoleate or methyl ricinoate, respectively, including several oxygen atoms.) EIS-MS of oligomers after isotopic exchange enabled estimation of OH and OOH groups.

Abstract: The drying behavior of air-drying high-solids paints (VOC<250 g/l) is different from and not as good as that of conventional paints. Research in relevant model compounds and alkyd paints has been initiated to gain insight in the underlying processes. After air-drying and aging, products whose formation could best be explained by assuming reaction with singlet oxygen were identified. Singlet oxygen can react with unsaturated systems in an efficient “ene” reaction to hydroperoxides. As hydroperoxides are essential in the air-drying process, an increased formation of singlet oxygen achieved by addition of (colored) sensitizers such as methylene blue and rose bengal should have a beneficial effect on alkyd drying. This effect was indeed found and appeared to be most pronounced at low temperatures. As a result the drying of high-solids alkyds and their corresponding paints is almost at the same rate as conventional products.

Abstract: Aluminum compounds, especially complexes of alcohols, are known as additional crosslinkers for air-drying alkyd paints. Particularly, the drying behavior of high-solids alkyd systems applied under adverse conditions may be improved distinctly. Besides the ether- and peroxy-crosslinks resulting from oxidative drying, coordinative crosslinking occurs. However, exterior weathering of paint films containing Al-complexes frequently results in severe embrittlement. In order to cope with these problems, drying and aging of alkyds and Al-complexes were investigated. All ligands in the complex appeared to get lost during drying, a probable cause of poor weathering performance. Using specially developed alkyd paints for Al-compounds, possible ways of controlling embrittlement are discussed.