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The use of carbon dioxide in the synthesis of chemicals, such as dimethyl carbonate (DMC), constitutes an environmentally attractive alternative to hazardous and toxic reagents. However, the direct synthesis of DMC from methanol and CO 2 is characterized by low yields due to the reaction equilibrium and the thermodynamic limitations . Alkoxide ionic liquids possessing alkylimidazolium and benzalkonium cations were prepared, characterised and tested together with ZrO 2 –MgO catalyst for the synthesis of DMC from methanol and CO 2 . By using the novel ionic liquid as additives, ca. 12% conversion of methanol, and 90% selectivity to DMC was obtained at 120 °C and 7.5 MPa. The water abstracting potential of the ionic liquids influenced the conversion of methanol and the selectivity to DMC. The alkoxide ionic liquids were recovered and reused in DMC synthesis without loss in activity and selectivity. Graphical abstract Synthesis of DMC from CO 2 and methanol catalysed by ZrO 2 –MgO using ionic liquid alkoxides as water abstracting additives. Comparison of the fresh and regenerated ionic liquid at 120 °C.

Dehydration of sugars to 5-hydroxymethylfurfural (HMF) has recently been under intensive study by a multitude of research groups. On the other hand, when lignocellulosic biomass is applied as the starting material, very few studies can be found in the open literature. The direct synthesis of HMF, in line with the idea of “one-pot” synthesis strategy from lignocellulose, is demanding since the overall process should encompass dissolution, hydrolysis, and dehydration steps in a single processing unit. Ionic liquid-assisted methods to produce hydroxymethyl-furfural directly from lignocellulosic biomass are reported here together with a short overview of the most important biofuels. In reality, HMF is not suitable to be used as a single-component fuel as such, and, consequently, methods to produce HMF derivatives suitable as liquid fuels are reported.

The isomerisation of α-pinene oxide to campholenic aldehyde, an expensive ingredient utilized by e.g. flavor industry, was studied over Supported Ionic Liquid Catalysts (SILCAs) consisting of catalytically active species residing in ionic liquid. The ionic liquid, in turn, was immobilized on a solid support material. SILCAs were demonstrated as efficient catalysts for the transformation of α-pinene oxide into campholenic aldehyde, with the product distribution and activity being dependent on the nature of the ionic liquid.

In this work, ionic liquid (IL) modified H-Beta zeolites were prepared and the physicochemical properties of the catalysts were investigated. IL modified zeolites were applied in 5-hydroxymethylfurfural (HMF) etherification to tert-butoxymethylfurfural (tBMF) which is a potential (bio)diesel component. The best catalyst, IL-H-Beta-25, yielded at BMF selectivity of 76 % corresponding to a HMF conversion of 46 %.

The use of carbon dioxide in the synthesis of chemicals, such as dimethyl carbonate (DMC), constitutes an environmentally attractive alternative to hazardous and toxic reagents. However, the direct synthesis of DMC from methanol and C[O.sub.2] is characterized by low yields due to the reaction equilibrium and the thermodynamic limitations ([DELTA][G.sup.o.sub.298K] = +26.3kJ/mol). Alkoxide ionic liquids possessing alkylimidazolium and benzalkonium cations were prepared, characterised and tested together with Zr[O.sub.2]MgO catalyst for the synthesis of DMC from methanol and C[O.sub.2]. By using the novel ionic liquid as additives, ca. 12% conversion of methanol, and 90% selectivity to DMC was obtained at 120 [degrees]C and 7.5 MPa. The water abstracting potential of the ionic liquids influenced the conversion of methanol and the selectivity to DMC. The alkoxide ionic liquids were recovered and reused in DMC synthesis without loss in activity and selectivity.

Dioxomolybdenum(VI) and oxotungsten(VI) complexes with a new amine bisphenol ligand (H 2 L) are reported. The ligand which carries a neutral nitrogen atom, two phenolic oxygen atoms and a thiophene side-arm was synthesized by a simple one-pot Mannich reaction. Further reaction with [MoO 2 (acac) 2 ] yielded a monomeric molybdenum complex [MoO 2 (L)(MeOH)] ( 2a ) or a dimeric complex [Mo 2 O 2 (μ-O) 2 (L) 2 ] ( 2b ), depending on the reaction conditions. The reaction with a tungsten trisglycolate [W(eg) 3 ] led to the formation of a monomeric compound [WO(eg)(L)] ( 3 ). In these complexes, the potentially tetradentate amine bisphenolate dianion coordinates as a tridentate O,N,O donor while the sulfur side-arm donor remains intact. The solid-state structure of 2a was investigated by X-ray crystallography.

Hydrogenation is an important and widely applied reaction in chemical industry. Supported ionic liquid (IL) type catalysts have shown good performance in various hydrogenation reactions. This chapter introduces a few case studies where supported IL catalysis has been applied in hydrogenation reactions. The case studies highlight the novelty of supported IL catalyst (SILCA) catalysts. Selective hydrogenation of α,ß‐unsaturated aldehydes, ketones, and esters, in general, is a versatile pathway to obtain many interesting products that can be used in perfumes, hardening of fats, preparation of pharmaceuticals, and synthesis of organic intermediates. SILCAs have been successfully demonstrated to act as catalysts in chemoselective hydrogenations, and thus an analogous concept has been applied for the synthesis of chiral metal complexes in ILs supported on heterogeneous catalysts.

Neurofilament light chain (NfL) is a novel biomarker reflecting neuroaxonal damage and associates with brain atrophy, and glial fibrillary acidic protein (GFAP) is a marker of astrocytic activation, associated with several neurodegenerative diseases. Since obesity is associated with increased risk for several neurodegenerative disorders, we hypothesized that circulating NfL and GFAP levels could reflect neuronal damage in obese patients. 28 morbidly obese and 18 lean subjects were studied with voxel based morphometry (VBM) MRI to assess gray and white matter densities. Serum NfL and GFAP levels were determined with single-molecule array. Obese subjects were re-studied 6 months after bariatric surgery. Morbidly obese subjects had lower absolute concentrations of circulating NfL and GFAP compared to lean individuals. Following bariatric surgery-induced weight loss, both these levels increased. Both at baseline and after weight loss, circulating NfL and GFAP values correlated inversely with eGFR. Cross-sectionally, circulating NfL levels correlated inversely with gray matter (GM) density, and this association remained significant also when accounting for age and total eGFR. GFAP values did not correlate with GM density. Our data suggest that when determining circulating NfL and GFAP levels, eGFR should also be measured since renal function can affect these measurements. Despite the potential confounding effect of renal function on NfL measurement, NfL correlated inversely with gray matter density in this group of subjects with no identified neurological disorders, suggesting that circulating NfL level may be a feasible biomarker of cerebral function even in apparently neurologically healthy subjects.

Experimental cardiac ischemia-reperfusion injury causes degradation of the glycocalyx and coronary washout of its components syndecan-1 and heparan sulfate. Systemic elevation of syndecan-1 and heparan sulfate is well described in cardiac surgery. Still, the events during immediate reperfusion after aortic declamping are unknown both in the systemic and in the coronary circulation. In thirty patients undergoing aortic valve replacement, arterial concentrations of syndecan-1 and heparan sulfate were measured immediately before and at one, five and ten minutes after aortic declamping (reperfusion). Parallel blood samples were drawn from the coronary sinus to calculate trans-coronary gradients (coronary sinus-artery). Compared with immediately before aortic declamping, arterial syndecan-1 increased by 18% [253.8 (151.6-372.0) ng/ml vs. 299.1 (172.0-713.7) ng/ml, p < 0.001] but arterial heparan sulfate decreased by 14% [148.1 (135.7-161.7) ng/ml vs. 128.0 (119.0-138.2) ng/ml, p < 0.001] at one minute after aortic declamping. There was no coronary washout of syndecan-1 or heparan sulfate during reperfusion. On the contrary, trans-coronary sequestration of syndecan-1 occurred at five [-12.96 ng/ml (-36.38-5.15), p = 0.007] and at ten minutes [-12.37 ng/ml (-31.80-6.62), p = 0.049] after reperfusion. Aortic declamping resulted in extracardiac syndecan-1 release and extracardiac heparan sulfate sequestration. Syndecan-1 was sequestered in the coronary circulation during early reperfusion. Glycocalyx has been shown to degrade during cardiac surgery. Besides degradation, glycocalyx has propensity for regeneration. The present results of syndecan-1 and heparan sulfate sequestration may reflect endogenous restoration of the damaged glycocalyx in open heart surgery.

Background: Mammography is the most common imaging modality for the detection of breast cancer. Artificial intelligence algorithms for mammography analysis have shown promising performance for breast cancer risk assessment and lesion detection and classification; however, these models often fail the test of external validation. The evidence points to variations in image acquisition—known as the batch effect—as a main contributing factor to the lack of the models generalization and robustness. However, studies on the effects of acquisition in the mammogram have been limited due to lack of appropriate datasets. This prospective, exploratory, non-randomized study aims to study how biological and non-biological sources of heterogeneity affect the mammogram and, in turn, the computerized models for mammography analysis. Methodology: This study will collect breast samples from 200 participants that will undergo breast resection as per clinical indications. Each sample will undergo the mammography imaging procedure several times to obtain mammograms with different combinations of imaging parameters. The resulting dataset will be used for the statistical analysis of the impact of imaging parameters in mammographic texture features and the computerized analysis of mammograms. Furthermore, biological information will be collected from the resected breast samples to study their relation to mammographic texture features. Discussion: This study will add to the understanding of the effect of different sources of heterogeneity on mammography, ultimately aiding in the future development of robust computerized analysis models.