Triacylglycerol Analysis of Fats and Oils by Evaporative Light Scattering Detection

A high performance liquid chromatography method with evaporative light scattering detection was developed for the analysis of oils and fats, which enabled excellent separation of major and minor triacylglycerol (TAG) species in 33 min, including regeneration of the column. The influence of the mobile phase and temperature on separation and analysis time were evaluated with a cocoa butter standard. The influence of the drift tube temperature and flow of the nebulising gas on the evaporative light scattering detector output signal was investigated by means of a response surface experimental design. Especially the flow of the nebulising gas had a profound effect on the detector signal. An optimal separation was obtained when using a 150 × 3.0 mm C18 column with 3 μm particle diameter at 20 °C and an acetonitrile/dichloromethane gradient at 0.72 mL/min. The maximum response was attained when the ELSD detector was set at the minimum temperature (45 °C) and a gas flow of 1.2 L/min. Finally, the linearity of the detector was investigated. It was found that at very low concentrations, the signal tends to flatten towards zero, giving an underestimation for minor TAG species, especially for oils or fats with a mixed fatty acid composition.     

Controller tuning freedom under plant identification uncertainty: double Youla beats gap in robust stability

In iterative schemes of identification and control one of the particular and important choices to make is the choice for a model uncertainty structure, capturing the uncertainty concerning the estimated plant model. Structures that are used in the recent literature encompass e.g. gap metric uncertainty, coprime factor uncertainty, and the Vinnicombe gap metric uncertainty. In this paper, we study the effect of these choices by comparing the sets of controllers that guarantee robust stability for the different model uncertainty bounds. In general these controller sets intersect. However in particular cases the controller sets are embedded, leading to uncertainty structures that are favourable over others. In particular, when restricting the controller set to be constructed as metric-bounded perturbations around the present controller, the so-called double Youla parametrization provides a set of robustly stabilizing controllers that is larger than corresponding sets that are achieved by using any of the other uncertainty structures. This is particularly of interest in controller tuning problems.     

A virus-based biocatalyst

Virus particles are probably the most precisely defined nanometre-sized objects that can be formed by protein self-assembly. Although their natural function is the storage and transport of genetic material, they have more recently been applied as scaffolds for mineralization and as containers for the encapsulation of inorganic compounds. The reproductive power of viruses has been used to develop versatile analytical methods, such as phage display, for the selection and identification of (bio)active compounds. To date, the combined use of self-assembly and reproduction has not been used for the construction of catalytic systems. Here we describe a self-assembled system based on a plant virus that has its coat protein genetically modified to provide it with a lipase enzyme. Using single-object and bulk catalytic studies, we prove that the virus-anchored lipase molecules are catalytically active. This anchored biocatalyst, unlike man-made supported catalysts, has the capability to reproduce itself in vivo, generating many independent catalytically active copies.     

Nanoparticles for Optical Molecular Imaging of Atherosclerosis

Molecular imaging contributes to future personalized medicine dedicated to the treatment of cardiovascular disease, the leading cause of mortality in industrialized countries. Endoscope‐compatible optical imaging techniques would offer a stand‐alone alternative and high spatial resolution validation technique to clinically accepted imaging techniques in the (intravascular) assessment of vulnerable atherosclerotic lesions, which are predisposed to initiate acute clinical events. Efficient optical visualization of molecular epitopes specific for vulnerable atherosclerotic lesions requires targeting of high‐quality optical‐contrast‐enhancing particles. In this review, we provide an overview of both current optical nanoparticles and targeting ligands for optical molecular imaging of atherosclerotic lesions and speculate on their applicability in the clinical setting.

     

Toll-Like Receptors in the Pathogenesis of Essential Hypertension. A Forthcoming Immune-Driven Theory in Full Effect

Essential hypertension (EH) is a highly heterogenous disease with a complex etiology. Recent evidence highlights the significant contribution of subclinical inflammation, triggered and sustained by excessive innate immune system activation in the pathogenesis of the disease. Toll-like receptors (TLRs) have been implied as novel effectors in this inflammatory environment since they can significantly stimulate the production of pro-inflammatory cytokines, the migration and proliferation of smooth muscle cells and the generation of reactive oxygen species (ROS), facilitating a low-intensity inflammatory background that is evident from the very early stages of hypertension. Furthermore, the net result of their activation is oxidative stress, endothelial dysfunction, vascular remodeling, and finally, vascular target organ damage, which forms the pathogenetic basis of EH. Importantly, evidence of augmented TLR expression and activation in hypertension has been documented not only in immune but also in several non-immune cells located in the central nervous system, the kidneys, and the vasculature which form the pathogenetic core systems operating in hypertensive disease. In this review, we will try to highlight the contribution of innate immunity in the pathogenesis of hypertension by clarifying the deleterious role of TLR signaling in promoting inflammation and facilitating hypertensive vascular damage.     

Increase in the coefficient of friction of the rolling stock disc brake via fluid cooling of its friction elements

The paper presents the results of theoretical and experimental investigations in the effect of a partial heat energy removal in the friction contact zone upon the disc brake coefficient of friction during braking. A fluid cooling system for the disc brake friction elements has been proposed based on a recuperative liquidpneumatic heat-exchange apparatus.     

Carbazole functionalized isocyanide brushes in heterojunction photovoltaic devices

In this work, carbazole-containing polyisocyanide (PIACz) brushes were used for photovoltaic devices. A photovoltaic device was fabricated on top of the brushes by spin-coating a suitable acceptor and evaporating an Al cathode. Devices with a poly(N-vinylcarbazole) (PVK) bulk polymer were also prepared for comparison. Interestingly, the brushes showed better photovoltaic characteristics as compared to the blended PVK system. This is attributed to the specific morphologies of the polyisocyanide brushes, which provide a large interfacial area between the donor and acceptor for efficient photogeneration. It was found that the device performance varied according to the molecular size of the incorporated acceptors.