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Item does not contain fulltext, Clofazimine is classified as a WHO group B drug for the treatment of rifampin-resistant tuberculosis. QT prolongation, which is associated with fatal cardiac arrhythmias, is caused by several antitubercular drugs, including clofazimine, but there are no data quantifying the effect of clofazimine concentration on QT prolongation. Our objective was to describe the effect of clofazimine exposure on QT prolongation. Fifteen adults drug-susceptible tuberculosis patients received clofazimine monotherapy as 300 mg daily for 3 days, followed by 100 mg daily in one arm of a 2-week, multiarm early bactericidal activity trial in South Africa. Pretreatment Fridericia-corrected QT (QTcF) (105 patients, 524 electrocardiograms [ECGs]) and QTcFs from the clofazimine monotherapy arm matched with clofazimine plasma concentrations (199 ECGs) were interpreted with a nonlinear mixed-effects model. Clofazimine was associated with significant QT prolongation described by a maximum effect (E(max)) function. We predicted clofazimine exposures using 100-mg daily doses and 2 weeks of loading with 200 and 300 mg daily, respectively. The expected proportions of patients with QTcF change from baseline above 30 ms (ΔQTcF > 30) were 2.52%, 11.6%, and 23.0% for 100-, 200-, and 300-mg daily doses, respectively. At steady state, the expected proportion with ΔQTcF of >30 ms was 23.7% and with absolute QTcF of >450 ms was 3.42% for all simulated regimens. The use of loading doses of 200 and 300 mg is not predicted to expose patients to an increased risk of QT prolongation, compared with the current standard treatment, and is, therefore, an alternative option for more quickly achieving therapeutic concentrations.

It is urgent to reduce CO2 emissions to mitigate the impacts of climate change. The development of advanced conversion technologies integrated with plasma torches provides a path for the optimisation of clean energy recovery from biomass and wastes, thus substituting fossil fuels utilization. This article presents the temperature characterisation within a laboratory-scale microwave-induced plasma reactor operated with air, H2O and CO2 as the plasma working gases. The benefits associated with the plasma torch are highlighted and include rapid responses of the plasma and the temperature profile within the reactor to changing operating conditions. The average temperature near the side wall in the laboratory-scale reactor is proportional to the applied microwave power, ranging from 550 °C at 2 kW to 850 °C at 5 kW, while significantly higher temperatures are locally present within the plasma plume. The described system demonstrates promising conditions that are ideal for effective energy recovery from biomass and wastes into clean fuel gas.

Substitution of fossil fuels by sustainable practices must be rapidly implemented to mitigate the impacts of climate change. The conversion of biomass into combustible gas is investigated in a microwave-induced plasma reactor using pure steam as the plasma working gas for the first time. The optimum results are achieved at the highest forward microwave power of 6 kW with biomass carbon conversion efficiency over 98% and complete biomass energy recovery in syngas. Unreacted steam is simply condensed out, leading to the production of a syngas with low inert dilution and high calorific value in the range 10.5–12 MJ/Nm3. The syngas produced is rich in hydrogen, exceeding 60% by volume. The proposed process could aid in the transition to a carbon neutral economy as it has the potential to efficiently convert biomass to syngas that can be used for the sustainable generation of fuels, chemicals and energy.

Enhancers are vitally important during embryonic development to control the spatial and temporal expression of genes. Recently, large scale genome projects have identified a vast number of putative developmental regulatory elements. However, the proportion of these that have been functionally assessed is relatively low. While enhancers have traditionally been studied using reporter assays, this approach does not characterise their contribution to endogenous gene expression. We have studied the murine Nestin (Nes) intron 2 enhancer, which is widely used to direct exogenous gene expression within neural progenitor cells in cultured cells and in vivo. We generated CRISPR deletions of the enhancer region in mice and assessed their impact on Nes expression during embryonic development. Loss of the Nes neural enhancer significantly reduced Nes expression in the developing CNS by as much as 82%. By assessing NES protein localization, we also show that this enhancer region contains repressor element(s) that inhibit Nes expression within the vasculature. Previous reports have stated that Nes is an essential gene, and its loss causes embryonic lethality. We also generated 2 independent Nes null lines and show that both develop without any obvious phenotypic effects. Finally, through crossing of null and enhancer deletion mice we provide evidence of trans-chromosomal interaction of the Nes enhancer and promoter.

When fuel gases (H2 and CH4) for fuel cells are produced from fossil fuels and biomass, there is a high possibility of presence of hydrogen sulfide (H2S). Because H2S can poison fuel cells and cause long lasting damage, it is necessary to rigorously remove H2S from fuel gases before use in fuel cells. With the advantages of high efficiency and low energy consumption, desulphurisation via adsorption at low temperatures has attracted the attention of many researchers and has seen recent advances. This review compares the performance of commonly-studied porous materials (metal oxides, activated carbon, zeolites, silica, and metal–organic frameworks (MOF)) that are used for adsorption at low temperatures. Test conditions such as feed gas compositions, feed gas velocity, and breakthrough concentration threshold are considered when comparing the adsorption performance of the materials. High performing materials from each material category are identified and future research directions are discussed.

In this work, we apply an amine-assisted silica pillaring method to create the first example of a porous Mo2TiC2MXene with nanoengineered interlayer distances. The pillared Mo2TiC2has a surface area of 202 m2g−1, which is among the highest reported for any MXene, and has a variable gallery height between 0.7 and 3 nm. The expanded interlayer distance leads to significantly enhanced cycling performance for Li-ion storage, with superior capacity, rate capably and cycling stability in comparison to the non-pillared analogue. The pillared Mo2TiC2achieved a capacity over 1.7 times greater than multilayered MXene at 20 mA g−1(≈320 mA h g−1) and 2.5 times higher at 1 A g−1(≈150 mA h g−1). The fast-charging properties of pillared Mo2TiC2are further demonstrated by outstanding stability even at 1 A g−1(under 8 min charge time), retaining 80% of the initial capacity after 500 cycles. Furthermore, we use a combination of spectroscopic techniques (i.e.XPS, NMR and Raman) to show unambiguously that the charge storage mechanism of this MXene occurs by a conversion reaction through the formation of Li2O. This reaction increases by 2-fold the capacity beyond intercalation, and therefore, its understanding is crucial for further development of this family of materials. In addition, we also investigate for the first time the sodium storage properties of the pillared and non-pillared Mo2TiC2

High purity hydrogen is one of the key factors in determining the lifetime of proton exchange membrane (PEM) fuel cells. However, the current industrial processes for producing high purity hydrogen are not only expensive, but also come with low energy efficiencies and productivity. Finding more cost-effective methods of purifying hydrogen is essential for ensuring wider scale deployment of PEM fuel cells. Among various hydrogen purification methods, adsorption in porous materials and membrane technologies are seen as two of the most promising candidates for the current industrial hydrogen purification methods, with metal organic frameworks (MOF) being particularly popular in research over the last decade. Despite many available reviews on MOFs, most focus on synthesis and production, with few reports focused on performance for hydrogen purification. This review describes the working principle and performance parameters of adsorptive separations and membrane materials and identifies MOFs that have been reported for hydrogen purification. The MOFs are summarised and their performance in separating hydrogen from common impurities (CO2, N2, CH4, CO) is compared systematically. The challenges of commercial application of MOFs for hydrogen purification are discussed. © 2020 Hydrogen Energy Publications LLC

Fuel cells (FC) have been developed for automobiles and stationary power units. In addition to a power generator function, we propose a new application of hydrogen isotope separation. In this paper, deuterium (D) separation is investigated by two types of AFCs with platinum (Pt) or ruthenium (Ru) anode catalysts. The characteristics of the AFCs are evaluated by pure protium (H) or deuterium gas separately. In the case of Pt catalyst, the cell current/voltage curves show similar results for both gases. But a remarkable decrease in the voltage value is observed probably due to the mass transportation (diffusion) limitation at Ru catalyst. The limitation effect was larger for D2 than H2 gas. The AC impedance measurements supports the slow reaction rate of D2 gas on Ru catalyst. The separation experiments are verified with hydrogen gas mixed with 1 at% D. The D is diluted in the unreacted gas discharged from AFC with Pt catalyst, but it is concentrated with Ru one. The inverse response may be attributed to the elementary process of the hydrogen oxidation reaction and the difference in the adsorption energy of gas and water molecules on the catalyst surface. © 2020 Hydrogen Energy Publications LLC