De standaard 'Het rode oog' (eerste herziening) van het Nederlands Huisartsen Genootschap; reactie vanuit de oogheelkunde

The revised guideline 'The red eye' of the Dutch College of General Practitioners contains adequate and scientifically well-supported recommendations for the diagnosis and management of patients with minor ocular trauma and red eyes. Unfortunately the guideline lacks a roadmap for implementation of these recommendations, as well as a definition of indicators for the measurement of implementation. This is important in the light of the limited implementation of the previous guideline 'The red eye' published in 199

Measuring Order in Regioregular Poly(3-hexylthiophene) with Solid-State ¹³C CPMAS NMR

We report on measurements of order in semicrystalline, high molar mass poly­(3-hexylthiophene) (P3HT) by solid-state ¹³C cross-polarization magic angle spinning (CPMAS) nuclear magnetic resonance (NMR) measurements. The relative degree of crystallinity was estimated for two films with different drying conditions via X-ray diffraction (XRD) and differential scanning calorimetry (DSC). Order determined by ¹³C NMR does not necessarily correlate with crystallinity, indicating that local order can occur in noncrystalline regions. Slow main chain dynamics influence the ¹³C NMR peak widths at lower temperatures (<0 °C), with side chain motions influencing the main chain motions. At higher temperatures (>0 °C), where narrower thiophene resonances are observed, these main chain conformation rearrangements occur on fast time scales (≪3 ms). This room-temperature dynamic disorder suggests that P3HT may be classified as a conformationally disordered (CONDIS) crystal

Characterization of Interfacial Structure in Polymer-Fullerene Bulk Heterojunctions via C-13 {H-2} Rotational Echo Double Resonance NMR

We introduce a new application of solid state NMR measurements towards characterizing the donor-acceptor interfaces within bulk heterojunction (BHJ) films. Rotational echo double resonance (REDOR) is used to measure dipolar couplings between C-13 nuclei on the acceptor phenyl-C-61-butyric acid methyl ester (PCBM) fullerene cage, which is approximate to 18% isotopically enriched with C-13, and beta hydrogens on the donor poly(3-hexyl thiophene) (P3HT) main chain, which are >95% isotopically enriched with H-2. The C-13 - H-2 dipolar couplings are used for constraining possible models of molecular packing in the amorphous mixed phase of a P3HT/PCBM BHJ. The films studied are highly mixed (>80%) and have a maximum length scale of composition nonuniformity of approximate to 6 nm in the mixed phase, as demonstrated by H-1 spin diffusion NMR and supported by TEM. The REDOR results show that despite the lack of phase separation at length scales greater than approximate to 6 nm, neat P3HT and PCBM clusters exist on approximate to 3 nm size scales, and, for the average PCBM molecule, the number of nearest neighbors P3HTs is two

A machine learning approach to explore predictors of graft detachment following posterior lamellar keratoplasty: a nationwide registry study

Machine learning can be used to explore the complex multifactorial patterns underlying postsurgical graft detachment after endothelial corneal transplantation surgery and to evaluate the marginal effect of various practice pattern modulations. We included all posterior lamellar keratoplasty procedures recorded in the Dutch Cornea Transplant Registry from 2015 through 2018 and collected the center-specific practice patterns using a questionnaire. All available data regarding the donor, recipient, surgery, and practice pattern, were coded into 91 factors that might be associated with the occurrence of a graft detachment. In this research, we used three machine learning methods; a regularized logistic regression (lasso), classification tree analysis (CTA), and random forest classification (RFC), to select the most predictive subset of variables for graft detachment. A total of 3647 transplants were included in our analysis and the overall prevalence of graft detachment was 9.9%. In an independent test set the area under the curve for the lasso, CTA, and RFC was 0.70, 0.65, and 0.72, respectively. Identified risk factors included: a Descemet membrane endothelial keratoplasty procedure, prior graft failure, and the use of sulfur hexafluoride gas. Factors with a reduced risk included: performing combined procedures, using pre-cut donor tissue, and a pre-operative laser iridotomy. These results can help surgeons to review their practice patterns and generate hypotheses for empirical research regarding the origins of graft detachments