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This study examines hydrophobic surface coatings for stimulation electrodes to mitigate foreign body reactions and encapsulation. Electrospinning of polydimethylsiloxane (PDMS) resin is explored to create fiber structures for electrode coatings. PDMS resin is succesfully processed into fiber mats. Electrospun PDMS fiber structures showed an increased water contact angle (124 °/125 °) in comparison to a cast flat film (102 °). To further increase hydrophobicity, the fabrication process of Slippery Liquid-Infused Porous Surface (SLIPS) systems with a polyurethane substrate and different natural lubricants is assessed with promising results in an increase in water contact angles up to 11°. The findings suggest the potential of these surface coatings to enhance the performance and safety of stimulation electrodes. [ABSTRACT FROM AUTHOR]

The groundbreaking discovery of vitamin E by Evans and Bishop in 1922 was an important milestone in vitamin research, inspiring further investigation into its crucial role in both human and animal nutrition. Supplementing vitamin E has been proved to enhance multiple key physiological systems such as the reproductive, circulatory, nervous and muscular systems. As the main antioxidant in the blood and on a cellular level, vitamin E maintains the integrity of both cellular and vascular membranes and thus modulates the immune system. This overview showcases important and innovative routes for synthesizing vitamin E on a commercial scale, provides cutting‐edge insights into formulation concepts for successful product form development and emphasizes the importance and future of vitamin E in healthy and sustainable animal nutrition. [ABSTRACT FROM AUTHOR]

We establish a general kinetic scheme for the energy transfer and radical-pair dynamics in photosystem I (PSI) of Chlamydomonas reinhardtii, Synechocystis PCC6803, Thermosynechococcus elongatus and Spirulina platensis grown under white-light conditions. With the help of simultaneous target analysis of transient-absorption data sets measured with two selective excitations, we resolved the spectral and kinetic properties of the different species present in PSI. WL-PSI can be described as a Bulk Chl a in equilibrium with a higher-energy Chl a, one or two Red Chl a and a reaction-center compartment (WL-RC). Three radical pairs (RPs) have been resolved with very similar properties in the four model organisms. The charge separation is virtually irreversible with a rate of ≈900 ns−1. The second rate, of RP1 → RP2, ranges from 70–90 ns−1 and the third rate, of RP2 → RP3, is ≈30 ns−1. Since RP1 and the Red Chl a are simultaneously present, resolving the RP1 properties is challenging. In Chlamydomonas reinhardtii, the excited WL-RC and Bulk Chl a compartments equilibrate with a lifetime of ≈0.28 ps, whereas the Red and the Bulk Chl a compartments equilibrate with a lifetime of ≈2.65 ps. We present a description of the thermodynamic properties of the model organisms at room temperature. [ABSTRACT FROM AUTHOR]

The selective reduction of terminal alkynes to alkenes was investigated using common cationic diphosphane rhodium complexes of the type [Rh(PP)(diolefin)]X (PP=diphosphane, X=anion). The effectiveness of the catalyst was demonstrated in the semi‐hydrogenation of dehydroisophytol (DIP), an industrial produced intermediate of vitamin E. The present study highlights the high activity and good selectivity of this simple catalytic system. However, deactivation increases at higher DIP concentrations. Several strategies to circumvent the deactivation are presented. [ABSTRACT FROM AUTHOR]

An efficient and highly selective semi‐hydrogenation of terminal alkynes to alkenes using neutral dimeric rhodium(I) complexes of the type [Rh(μ‐Cl)(PP)]2 is presented. Dehydroisophytol (DIP) was chosen as the alkyne for this study because of its high importance in the industrial production of synthetic vitamin E. Excellent selectivity of over 91% towards the alkene was achieved with known and new rhodium catalysts. No deactivation was observed for the [Rh(μ‐Cl)(PP)]2 complexes and the molar Rh:DIP ratio could be increased to 1:20 000, and importantly, no reduction in selectivity was observed. The results presented open the door to the industrial application of homogeneous rhodium complexes in the semi‐hydrogenation of terminal alkynes. [ABSTRACT FROM AUTHOR]

Isophorone is a technically important compound used as a high-boiling-point solvent for coatings, adhesives, etc., and it is used as a starting material for various valuable compounds, including isophorone diisocyanate, a precursor for polyurethanes. For over 80 years, isophorone has been synthesized via base-catalyzed self-condensation of acetone. This reaction has a complex reaction mechanism with numerous possible reaction steps including the formation of isophorone, triacetone dialcohol, and ketonic resins. This review provides an overview of the different production processes of isophorone in liquid- and vapor-phase and reviews the literature-reported selectivity toward isophorone achieved using different reaction parameters and catalysts. [ABSTRACT FROM AUTHOR]

2022 marks the centenary of the discovery of vitamin E by Evans and Bishop, an important milestone in vitamin research. An enormous amount of scientific data related to the importance of its activity has been published on this micronutrient. Globally, researchers from industry and academia have contributed to improve and implement highly efficient and commercially viable production processes for vitamin E. All processes share a common final step, but differ in the generation of their key building blocks. Today, Vitamin E, accounts for a worldwide production of >75.000 t/a. Vitamin E is applied predominantly as feed supplement for various animal species and in addition is used in a variety of human applications. Moreover, its impressive antioxidative behavior enables frequent use as stabilizing ingredient in many product forms and final consumer applications. This review will provide the current state of science, with clear focus on highlighting the different routes for industrial syntheses of vitamin E. Furthermore, approaches directed towards successful product form development including suitable auxiliary substances combined with appropriate formulation technologies, as well as a broad variety of applications in animal and human nutrition and health will be discussed. Insights on isolation approaches, biosynthesis, and future trends complete the status of Vitamin E research. [ABSTRACT FROM AUTHOR]