The effect of addition of a third component on the behaviour of the lithium doped magnesium catalysts for the oxidative dehydrogenation of ethane

The oxidative dehydrogenation of ethane was studied with the use of promoted Li/MgO catalysts at temperatures of 600¿650°C. The addition of known promoters, cobalt and tin, gave a slight Increase In activity but a strong decrease in selectivity to ethylene under the conditions used. The addition of sodium improved the selectivity to ethylene and suppressed the formation of carbon monoxide. Using a feed of 12 vol% ethane and 6 vol% oxygen, the U/Na/MgO catalyst with 3.2wt% sodium showed a selectivity of 86 % to ethylene at 38 % conversion of ethane; the Li/MgO catalyst showed a selectivity of 80 % at similar conversions Thermal Investigations of the Li/Na/MgO catalyst showed that an eutectic melt of LINaCO3 is formed at 490°C; the existence of this molten phase is probably the cause of the Increased selectivity

Moisture sorption by dairy powders studied by low-field NMR

The influence of moisture sorption on spin–spin (T2) relaxation times for skim milk powder (SMP), milk protein concentrates (MPC50 and MPC80) and amorphous lactose was studied by low-field nuclear magnetic resonance (NMR). For amorphous lactose and MPC80, only one main peak was observed in the T2 distribution, whereas for SMP and MCP50, two main peaks, relating to the water associated with the amorphous lactose and protein, were observed at aw w >0.4 lactose crystallised and no peak relating to water associated with lactose was visible in the T2 spectrum (water of crystallisation for crystalline lactose has shorter relaxation times, which cannot be detected by low-field NMR). T2 peak position and peak area for the protein fraction increased with increasing aw. Shifts in the T2 peak position showed the transition from mono- and bilayer water at low aw to more rapidly exchanging forms of water at higher aw.</p

Streefwaarden voor de volksgezondheid

This contribution advocates embedding public health benchmarks in Dutch legislation, analogous to the Dutch environmental legislation. International and national policy statements including the Sustainable Development Goals offer a basis for identifying such benchmarks. The legislative basis offers a ground for holding government to account in case of a failure to meet its public health goals.This contribution advocates embedding public health benchmarks in Dutch legislation, analogous to the Dutch environmental legislation. International and national policy statements including the Sustainable Development Goals offer a basis for identifying such benchmarks. The legislative basis offers a ground for holding government to account in case of a failure to meet its public health goals

Drop impact upon micro- and nanostructured superhydrophobic surfaces

We experimentally investigate drop impact dynamics onto different superhydrophobic surfaces, consisting of regular polymeric micropatterns and rough carbon nanofibers, with similar static contact angles. The main control parameters are the Weber number \We and the roughness of the surface. At small \We, i.e. small impact velocity, the impact evolutions are similar for both types of substrates, exhibiting Fakir state, complete bouncing, partial rebouncing, trapping of an air bubble, jetting, and sticky vibrating water balls. At large \We, splashing impacts emerge forming several satellite droplets, which are more pronounced for the multiscale rough carbon nanofiber jungles. The results imply that the multiscale surface roughness at nanoscale plays a minor role in the impact events for small \We \apprle 120 but an important one for large \We \apprge 120. Finally, we find the effect of ambient air pressure to be negligible in the explored parameter regime \We \apprle 150Comment: 8 pages, 7 figure

UV-induced ligand exchange in MHC class I protein crystals

High-throughput structure determination of protein−ligand complexes is central in drug development and structural proteomics. To facilitate such high-throughput structure determination we designed an induced replacement strategy. Crystals of a protein complex bound to a photosensitive ligand are exposed to UV light, inducing the departure of the bound ligand, allowing a new ligand to soak in. We exemplify the approach for a class of protein complexes that is especially recalcitrant to high-throughput strategies: the MHC class I proteins. We developed a UV-sensitive, “conditional”, peptide ligand whose UV-induced cleavage in the crystals leads to the exchange of the low-affinity lytic fragments for full-length peptides introduced in the crystallant solution. This “in crystallo” exchange is monitored by the loss of seleno-methionine anomalous diffraction signal of the conditional peptide compared to the signal of labeled MHC β2m subunit. This method has the potential to facilitate high-throughput crystallography in various protein families

Class I major histocompatibility complexes loaded by a periodate trigger

Class I major histocompatibility complexes (MHCs) present peptide ligands on the cell surface for recognition by appropriate cytotoxic T cells. The unstable nature of unliganded MHC necessitates the production of recombinant class I complexes through in vitro refolding reactions in the presence of an added excess of peptides. This strategy is not amenable to high-throughput production of vast collections of class I complexes. To address this issue, we recently designed photocaged MHC ligands that can be cleaved by a UV light trigger in the MHC bound state under conditions that do not affect the integrity of the MHC structure. The results obtained with photocaged MHC ligands demonstrate that conditional MHC ligands can form a generally applicable concept for the creation of defined peptide−MHCs. However, the use of UV exposure to mediate ligand exchange is unsuited for a number of applications, due to the lack of UV penetration through cell culture systems and due to the transfer of heat upon UV irradiation, which can induce evaporation. To overcome these limitations, here, we provide proof-of-concept for the generation of defined peptide−MHCs by chemical trigger-induced ligand exchange. The crystal structure of the MHC with the novel chemosensitive ligand showcases that the ligand occupies the expected binding site, in a conformation where the hydroxyl groups should be reactive to periodate. We proceed to validate this technology by producing peptide−MHCs that can be used for T cell detection. The methodology that we describe here should allow loading of MHCs with defined peptides in cell culture devices, thereby permitting antigen-specific T cell expansion and purification for cell therapy. In addition, this technology will be useful to develop miniaturized assay systems for performing high-throughput screens for natural and unnatural MHC ligands

Expression of the Serpin Serine Protease Inhibitor 6 Protects Dendritic Cells from Cytotoxic T Lymphocyte–Induced Apoptosis: Differential Modulation by T Helper Type 1 and Type 2 Cells

Dendritic cells (DCs) play a central role in the immune system as they drive activation of T lymphocytes by cognate interactions. However, as DCs express high levels of major histocompatibility complex class I, this intimate contact may also result in elimination of DCs by activated cytotoxic T lymphocytes (CTLs) and thereby limit induction of immunity. We show here that immature DCs are indeed susceptible to CTL-induced killing, but become resistant upon maturation with anti-CD40 or lipopolysaccharide. Protection is achieved by expression of serine protease inhibitor (SPI)-6, a member of the serpin family that specifically inactivates granzyme B and thereby blocks CTL-induced apoptosis. Anti-CD40 and LPS-induced SPI-6 expression is sustained for long periods of time, suggesting a role for SPI-6 in the longevity of DCs. Importantly, T helper 1 cells, which mature DCs and boost CTL immunity, induce SPI-6 expression and subsequent DC resistance. In contrast, T helper 2 cells neither induce SPI-6 nor convey protection, despite the fact that they trigger DC maturation with comparable efficiency. Our data identify SPI-6 as a novel marker for DC function, which protects DCs against CTL-induced apoptosis

The relationship between Europeanisation and policy styles: a study of agricultural and public health policymaking in three EU Member States

© 2020 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group. This is an Open Access article distributed under the terms of the Creative Commons Attribution-NonCommercial-NoDer-ivatives License (http://creativecommons.org/licenses/by-nc-nd/4.0/), which permits non-commercial re-use, distri-bution, and reproduction in any medium, provided the original work is properly cited, and is not altered, transformed, or built upon in any way.The role of policy styles in policymaking has attracted renewed scholarly interestin recent years. One of the central debates in this literature revolves around thequestion of how to reconcile archetype national policy styles with considerabledifferences in modus operandi across policy sectors. A sector-specific featurethat is considered a key determinant of the manifestation of archetypenational policy styles in the European Union is the degree of Europeanisationof policy sectors. This paper picks up this suggestion by addressing thequestion of whether and how Europeanisation affects the degree to whichfeatures of an archetype national policy style are manifest within a sector. Weaddress this question by exploring sectoral policy styles in agricultural andfood-related public health policymaking across three EU Member States: TheNetherlands, the United Kingdom (England), and France. Our findings suggestthat the degree of Europeanisation of a policy sector does prove an importantcondition that helps to understand the relationship between national andsectoral policy styles. More specifically, Europeanisation has the strongesteffect when sectors face a higher adaptation pressure, i.e., when there is alarger misfit between sectoral regimes and EU-induced institutional demands.We suggest various promising avenues of future research on this relationship.Peer reviewe