Influence of Solid Supports on Acyl Migration in 2-Monoacylglycerols: Purification of 2-MAG via Flash Chromatography

Soybean oil 2-monoacylglycerol (2-MAG) was synthesized via the Novozym 435-catalyzed ethanolysis of triacylglycerols and purified by conventional liquid–liquid extraction. The 2-MAG was subjected to incubation at 20 and 40 °C in the presence of five solid commercial support materials, Lewatit, Silica Gel 60, Alumina–Neutral Brockman Activity 1, Amberlyst-15, and SBA-15, to determine their effects on acyl migration rates. Lewatit and SBA-15 did not catalyze acyl migration rates after 144 h, while silica gel slightly increased migration rates. The more polar alumina and the cationic Amberlyst 15 significantly increased migration rates. Flash chromatography purification of 2-MAG using silica gel as the immobile phase developed with an acetone/hexane binary gradient proved to be a comparable purification method to liquid–liquid extraction, resulting in 60 % 2-MAG yield, no residual triacylglycerol, diacylglycerol, or glycerol co-products, and a 95 mol% 2-MAG purity vs. 1-MAG, demonstrating that flash chromatography did not catalyze acyl migration.     

Computation of the loading diagram and the tensile strength of carbon nanotube networks

A modification is suggested to the Brenner potential cut-off function in order to compute atomic forces of carbon nanostructures in a more realistic way and giving a possibility to fit the atomic forces to experimental data. With the modified Brenner potential, the loading diagram and the tensile strength were determined for an example of the carbon nanotube networks. According to these new computational results carbon nanotube networks can be the materials which inherit the extremely high strength of the graphite sheet and they bring this property in all directions of the 3D space (not only in one direction as the nanotubes).     

Changes of the nutrient loads of the Danube since the late eighties: An analysis based on long term changes along the whole Danube River and its main tributaries.

The Danube nutrient loads are affected by human impacts mainly from agriculture and wastewater discharges. Knowledge about the Danube nutrient loads and the changes of these loads over time is essential for understanding the changes within the ecosystem of the Black Sea, induced by these loads. The paper shows the long term changes of the nutrient load along the Danube estimated by measurements from different countries and institutions. The results show large differences between Dissolved Inorganic Nitrogen (DIN) and Total Phosphorus (TP). For TP, the Danube River loads show a strong decrease since 1988-1992, especially in the Middle and Lower basin. This change is probably partly connected to the dramatic economic changes in the Middle and Eastern European countries following the collapse of the communist system. The DIN load does not show a decreasing trend in the last decade. The data indicate that there may be a decreasing trend in the anthropogenic emissions, but that such a trend is counteracted by a significantly increasing trend of the Danube discharge in the last decade. The accuracy of the available data is analysed in the paper as well.     

Purinergic–Glycinergic Interaction in Neurodegenerative and Neuroinflammatory Disorders of the Retina

Neurodegenerative–neuroinflammatory disorders of the retina seriously hamper human vision. In searching for key factors that contribute to the development of these pathologies, we considered potential interactions among purinergic neuromodulation, glycinergic neurotransmission, and microglia activity in the retina. Energy deprivation at cellular levels is mainly due to impaired blood circulation leading to increased release of ATP and adenosine as well as glutamate and glycine. Interactions between these modulators and neurotransmitters are manifold. First, P2Y purinoceptor agonists facilitate reuptake of glycine by glycine transporter 1, while its inhibitors reduce reverse-mode operation; these events may lower extracellular glycine levels. The consequential changes in extracellular glycine concentration can lead to parallel changes in the activity of NR1/NR2B type NMDA receptors of which glycine is a mandatory agonist, and thereby may reduce neurodegenerative events in the retina. Second, P2Y purinoceptor agonists and glycine transporter 1 inhibitors may indirectly inhibit microglia activity by decreasing neuronal or glial glycine release in energy-compromised retina. These inhibitions may have a role in microglia activation, which is present during development and progression of neurodegenerative disorders such as glaucomatous and diabetic retinopathies and age-related macular degeneration or loss of retinal neurons caused by thromboembolic events. We have hypothesized that glycine transporter 1 inhibitors and P2Y purinoceptor agonists may have therapeutic importance in neurodegenerative–neuroinflammatory disorders of the retina by decreasing NR1/NR2B NMDA receptor activity and production and release of a series of proinflammatory cytokines from microglial cells.     

The High-Frequency Base Converter?A New Approach to Static High-Power Conversion

A new approach to high-power conversion in which two naturally commutated converters (cycloconverters) are used in tandem, each with its input connected to a (passive) high-frequency (HF) source (``base') is presented. The arrangement approximates an ideal converter; its ``input' and ``output' frequency can be equal or different, and the power factor at both external terminals can be maintained at unity or any other value. Potential utility applications in which the HF base converter functions as an asynchronous intertie between two ac power systems and as a tie between a dc transmission line and a weak ac system are discussed, and technical and economic comparisons with conventional approaches are given.     

The Influence of Package Size and Flute Type of Corrugated Boxes on Load Bridging in Unit Loads

Shipping pallets often are designed with the assumption that the payload carried is flexible and uniformly distributed on the pallet surface. However, packages on the pallet can act as a series of discrete loads, and the physical interactions among the packages can add stiffness to the pallet/load combination. The term ‘load bridging’ has been used to describe this phenomenon. The study reported in this paper investigated the relationships of package size, corrugated flute type and pallet stiffness to load bridging and the resulting unit‐load deflection. The experimental results indicated that an increase in box size changed the unit‐load deflection by as much as 75%. Flute type was found to impact load bridging and the resulting unit‐load deflection. Changing the corrugated box flute type from B‐flute or BC‐flute to E‐flute reduces the unit‐load deflection by as much as 40%. Also, experimental data indicates that the effect of package size and corrugated board flute type on pallet deflection is the greatest for low stiffness pallets. The results provide information that can be used to design unit loads that use material more efficiently. Copyright © 2017 John Wiley & Sons, Ltd.     

A novel tool for summarization of arthroscopic videos

Arthroscopic surgery is a minimally invasive procedure that uses a small camera to generate video streams, which are recorded and subsequently archived. In this paper we present a video summarization tool and demonstrate how it can be successfully used in the domain of arthroscopic videos. The proposed tool generates a keyframe-based summary, which clusters visually similar frames based on user-selected visual features and appropriate dissimilarity metrics. We discuss how this tool can be used for arthroscopic videos, taking advantage of several domain-specific aspects, without losing its ability to work on general-purpose videos. Experimental results confirm the feasibility of the proposed approach and encourage extending it to other application domains.     

Combining algorithms for automatic detection of optic disc and macula in fundus images

This paper proposes an efficient combination of algorithms for the automated localization of the optic disc and macula in retinal fundus images. There is in fact no reason to assume that a single algorithm would be optimal. An ensemble of algorithms based on different principles can be more accurate than any of its individual members if the individual algorithms are doing better than random guessing. We aim to obtain an improved optic disc and macula detector by combining the prediction of multiple algorithms, benefiting from their strength and compensating their weaknesses. The location with maximum number of detectors’ outputs is formally the hotspot and is used to find the optic disc or macula center. An assessment of the performance of integrated system and detectors working separately is also presented. Our proposed combination of detectors achieved overall highest performance in detecting optic disc and fovea closest to the manually center chosen by the retinal specialist.     

Preparation of ion exchangers from bagasse by crosslinking with epichlorohydrin-NH4OH or epichlorohydrin-imidazole

Sugar cane bagasse was crosslinked with epichlorohydrin in the presence of NH₄OH or imidazole. The obtained water-insoluble products were characterized in terms of yield, anion-exchange capacity, packed volume, and dye-binding properties. Yields were highest using a 3: 1 epichlorohydrin to NH₄OH molar ratio, producing weak anion exchangers. The weak anon exchangers had low dye-binding capacities compared to their total anion-exchange capacities. A 2 : 1 epichlorohydrin-to-imidazole molar ratio proved best for making strong anion exchangers from bagasse. The strong anion exchangers had dye-binding capacities comparable to their anion-exchange capacities, indicating that they might be useful for removing anionic dyes from wastewater. © 1997 John Wiley & Sons, Inc. J Appl Polym Sci 64: 2561–2566, 1997