11 research outputs found

    Development of sustainable chemical technologies using low-cost ionic liquids for waste decontamination and valorization

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    This work proposed and investigated key strategies that contribute to the advancements of low-cost protic ILs (PILs) for use in the future sustainable chemical industry, particularly in the areas of waste valorization and decontamination. In large, this PhD research contributed to the ongoing development of a lignocellulose fractionation process using PILs. First, the use of contaminated waste wood was investigated as a low-cost alternative feedstock to expensive virgin biomass. Fractionation of post-consumer waste wood collected from construction activities was shown to be highly effective using 1-methylimidazolium chloride [H1Cim]Cl, producing a highly digestible metal-free cellulose pulp, with >70% glucose yield during enzymatic hyrolysis. Evaluation of key process parameters such as solid loading, waste wood composition variation, metal chelation with lignin and IL-clean up were also investigated. The study was expanded to include the valorization of hazardous creosote waste wood using the low-cost PIL N,N,N-dimethylbutylammonium hydrogen sulfate [DMBA][HSO4]. The fractionation produced a highly digestible, PAH-free cellulose pulp stream with 70% glucose release, and a PAH-lignin stream. Second, to develop a better understanding of the process boundary conditions, water use as co-solvent and anti-solvent was investigated using a variety of promising lignocellulosic biomass. It was shown that the impact of water as a co-solvent on the fractionation ability of [DMBA][HSO4] is feedstock-dependent. A reduced water input for lignin precipitation was found not to compromise the cellulose digestibility, while significantly reducing the process energy. In addition, the impact of ionoSolv pretreatment severity on fractionation performance was evaluated using a modified pretreatment severity factor, incorporating the Hammett acidity of the aqueous IL solution. The modified severity factor can better predict the fractionation outcome compared to the classical pretreatment severity factor, particularly regarding delignification and hemicellulose removal. Attention was then turned to utilization of the cellulose pulp derived from the ionoSolv process to produce functionalized nanocellulose crystals (CNCs). Alkaline-H2O2 oxidation was used as a simple and more environmentally friendly method for facile extraction of carboxylated CNCs. The impact of pretreatment severity and cellulose composition on the properties of extracted CNCs was evaluated. The produced CNCs had the ability to form self-standing nanofilms and exhibited similar thermal and colloidal stability to CNCs produced by TEMPO-mediated oxidation. Lastly, a novel approach for textile waste decontamination and synthetic dye reuse using PILs was developed. The PIL [DMBA][HSO4] was used to selectively extract dyes from polyester-based synthetic textiles, leaving the dye-free polyester fiber behind for upcycling. Subsequent dyeing using the dye-rich [DMBA][HSO4] solutions was shown to be possible, achieving a similar color strength to commercially dyed products. The process provides key and novel advantages that can provide a new circular dimension to the textile recycling sector by eliminating virgin dye use, applying a closed-loop solvent-based dyeing process, and creating dye-free polyester fibers.Open Acces

    From waste to food : optimising the breakdown of oil palm waste to provide substrate for insects farmed as animal feed

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    Waste biomass from the palm oil industry is currently burned as a means of disposal and solutions are required to reduce the environmental impact. Whilst some waste biomass can be recycled to provide green energy such as biogas, this investigation aimed to optimise experimental conditions for recycling palm waste into substrate for insects, farmed as a sustainable high-protein animal feed. NMR spectroscopy and LC-HRMS were used to analyse the composition of palm empty fruit bunches (EFB) under experimental conditions optimised to produce nutritious substrate rather than biogas. Statistical pattern recognition techniques were used to investigate differences in composition for various combinations of pre-processing and anaerobic digestion (AD) methods. Pre-processing methods included steaming, pressure cooking, composting, microwaving, and breaking down the EFB using ionic liquids. AD conditions which were modified in combination with pre-processing methods were ratios of EFB:digestate and pH. Results show that the selection of pre-processing method affects the breakdown of the palm waste and subsequently the substrate composition and biogas production. Although large-scale insect feeding trials will be required to determine nutritional content, we found that conditions can be optimised to recycle palm waste for the production of substrate for insect rearing. Pre-processing EFB using ionic liquid before AD at pH6 with a 2:1 digestate:EFB ratio were found to be the best combination of experimental conditions

    Bi-allelic genetic variants in the translational GTPases GTPBP1 and GTPBP2 cause a distinct identical neurodevelopmental syndrome

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    : The homologous genes GTPBP1 and GTPBP2 encode GTP-binding proteins 1 and 2, which are involved in ribosomal homeostasis. Pathogenic variants in GTPBP2 were recently shown to be an ultra-rare cause of neurodegenerative or neurodevelopmental disorders (NDDs). Until now, no human phenotype has been linked to GTPBP1. Here, we describe individuals carrying bi-allelic GTPBP1 variants that display an identical phenotype with GTPBP2 and characterize the overall spectrum of GTP-binding protein (1/2)-related disorders. In this study, 20 individuals from 16 families with distinct NDDs and syndromic facial features were investigated by whole-exome (WES) or whole-genome (WGS) sequencing. To assess the functional impact of the identified genetic variants, semi-quantitative PCR, western blot, and ribosome profiling assays were performed in fibroblasts from affected individuals. We also investigated the effect of reducing expression of CG2017, an ortholog of human GTPBP1/2, in the fruit fly Drosophila melanogaster. Individuals with bi-allelic GTPBP1 or GTPBP2 variants presented with microcephaly, profound neurodevelopmental impairment, pathognomonic craniofacial features, and ectodermal defects. Abnormal vision and/or hearing, progressive spasticity, choreoathetoid movements, refractory epilepsy, and brain atrophy were part of the core phenotype of this syndrome. Cell line studies identified a loss-of-function (LoF) impact of the disease-associated variants but no significant abnormalities on ribosome profiling. Reduced expression of CG2017 isoforms was associated with locomotor impairment in Drosophila. In conclusion, bi-allelic GTPBP1 and GTPBP2 LoF variants cause an identical, distinct neurodevelopmental syndrome. Mutant CG2017 knockout flies display motor impairment, highlighting the conserved role for GTP-binding proteins in CNS development across species

    Corrosion Behavior of Carbon Steel in CO2 Saturated Amine and Imidazolium-, Ammonium-, and Phosphonium-Based Ionic Liquid Solutions

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    This work presents a recent investigation on corrosion behavior of carbon steel amine and ionic liquid based carbon dioxide absorbents. The first class focused on classical amine solutions: monoethanolamine (MEA), diethanolamine, and methyldiethanolamine. The second class included activated amine blends using piperazine (PZ) amine promoter. The third class included novel aqueous mixtures of alkanolamine/hydrophilic room-temperature ionic liquids (RTILs), namely, [BMIM][BF4], [BMIM][Otf], [P4441][Acetate], and [Choline][Acetate]. Electrochemical corrosion experiments were conducted using polarization techniques to determine the corrosion rate of steel probing the effect of process temperature and CO2 loading. The findings of the investigation show that corrosivity of classical amines is governed by their characteristic CO2 absorption capacity whereas PZ-activated amines resulted in lower corrosion rates and higher CO2 absorption. The partial replacement of aqueous phase in MEA solution by RTILs was shown to be effective in reducing steel corrosion rates with phosphonium- and ammonium-based RTILs shown to be more effective than imidazolium-based RTILs. 2015 American Chemical Society.Scopu

    Industrial sludge valorization and decontamination via lipid extraction and heavy metals removal using low-cost protic ionic liquid

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    Sludge is a heterogenous organic-rich matter that comprise of highly valuable biopolymers along with various contaminants including heavy metals. Sludge valorization as a renewable resource and inexpensive feedstock is key for sludge realization in circular economy context. This study presents the use of low-cost protic ionic liquid (PIL) as an integrated process medium to decontaminate heavy metal contaminated industrial sludge while selectively extract the lipid content. The treatment process focused on the use of 1-methylimidazole chloride for its higher heavy metal extraction performance compared to other screened ionic liquids (ILs). The treatment was also able to selectively extract lipids from industrial sludge, leaving a protein/carbohydrate rich solid product. Process temperature was shown to have a key impact on the biopolymers' fractionation. Operating at temperatures above 120 °C resulted in higher recovery of proteins in the lipid-rich fraction, compromising the quality of the lipid stream. Variation of the PIL acid/base (a/b) ratio also had a significant impact on the deconstruction of the sludge biopolymers, with a/b ratio of 1 resulting in highest recovery of all biopolymers. Optimal water concentration as co-solvent was found at 30 wt%, with lipid recovery reaching 60% and heavy metals extraction ranging between 29 and 89%.This research is made possible by the PDRA award ( PDRA6-0602-20007 ) from Qatar National Research Fund (QNRF). In addition, the authors wish to thank the Central Laboratories Unit (CLU) at Qatar University for the heavy metals analysis. Also, the authors wish to thank Ms. Touria Bounnit from the Center for Sustainable Development at Qatar University for the assistant in the lipids analysis. The statements made herein are solely the responsibility of the authors.Scopu

    Efficient extraction of lipids from microalgal biomass for the production of biofuels using low-cost protic ionic solvents

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    The valorization of lipids available in microalgal biomass supports the indispensable transition from fossil fuels to renewable energy systems such as biofuels. Ionic liquids have been long investigated for the effective extraction of those lipids, however; the complex and expensive synthesis of traditional ionic liquids (i.e., >50/kg)hinderedtheiremploymentincommercialapplications.Proticionicliquidsareaclassofionicliquidsthatpossessasimplemethodofpreparationandalowcostofaround50/kg) hindered their employment in commercial applications. Protic ionic liquids are a class of ionic liquids that possess a simple method of preparation and a low cost of around 1-3/kg, rendering them viable for industrial implementation. This study investigates, for the first time, the deployment of protic ionic liquids with methanol co-solvent for the extraction of lipids from Coelastrella sp. and Haematococcus sp. microalgae. The treatment process focused on the use of N,N,N-dimethyl-butylammonium hydrogen sulfate due to its high lipid extraction performance of 323.3 mg lipids/g biomass from Coelastrella sp. (81% of available lipids) compared to other screened ionic liquids. Process parameters such as temperature, time, and ionic liquid to methanol mass ratio exhibited a key impact on the lipid yield. The fatty acid profile of the extracted lipids from Coelastrella sp. demonstrated suitability to produce biofuels. The treatment has also shown selectivity in extracting lipids while leaving behind a protein/carbohydrate rich solid residue. The results obtained suggest that protic ionic liquids are promising candidates for the cost-effective and eco-friendly treatment of microalgal biomass. 2023 Elsevier B.V.The authors gratefully acknowledge the financial support provided by Qatar National Research Fund , research grant ( PDRA6-0602-20007 ). The authors would like to express their appreciation for Dr. Touria Bounnit from the department for sustainable development at Qatar University for doing the GC-FID analysis. The statements made herein are solely the responsibility of the authors.Scopu

    SARS-CoV-2 vaccination modelling for safe surgery to save lives: data from an international prospective cohort study

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    Background: Preoperative SARS-CoV-2 vaccination could support safer elective surgery. Vaccine numbers are limited so this study aimed to inform their prioritization by modelling. Methods: The primary outcome was the number needed to vaccinate (NNV) to prevent one COVID-19-related death in 1 year. NNVs were based on postoperative SARS-CoV-2 rates and mortality in an international cohort study (surgical patients), and community SARS-CoV-2 incidence and case fatality data (general population). NNV estimates were stratified by age (18-49, 50-69, 70 or more years) and type of surgery. Best- and worst-case scenarios were used to describe uncertainty. Results: NNVs were more favourable in surgical patients than the general population. The most favourable NNVs were in patients aged 70 years or more needing cancer surgery (351; best case 196, worst case 816) or non-cancer surgery (733; best case 407, worst case 1664). Both exceeded the NNV in the general population (1840; best case 1196, worst case 3066). NNVs for surgical patients remained favourable at a range of SARS-CoV-2 incidence rates in sensitivity analysis modelling. Globally, prioritizing preoperative vaccination of patients needing elective surgery ahead of the general population could prevent an additional 58 687 (best case 115 007, worst case 20 177) COVID-19-related deaths in 1 year. Conclusion: As global roll out of SARS-CoV-2 vaccination proceeds, patients needing elective surgery should be prioritized ahead of the general population

    Rare predicted loss-of-function variants of type I IFN immunity genes are associated with life-threatening COVID-19

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    BackgroundWe previously reported that impaired type I IFN activity, due to inborn errors of TLR3- and TLR7-dependent type I interferon (IFN) immunity or to autoantibodies against type I IFN, account for 15-20% of cases of life-threatening COVID-19 in unvaccinated patients. Therefore, the determinants of life-threatening COVID-19 remain to be identified in similar to 80% of cases.MethodsWe report here a genome-wide rare variant burden association analysis in 3269 unvaccinated patients with life-threatening COVID-19, and 1373 unvaccinated SARS-CoV-2-infected individuals without pneumonia. Among the 928 patients tested for autoantibodies against type I IFN, a quarter (234) were positive and were excluded.ResultsNo gene reached genome-wide significance. Under a recessive model, the most significant gene with at-risk variants was TLR7, with an OR of 27.68 (95%CI 1.5-528.7, P=1.1x10(-4)) for biochemically loss-of-function (bLOF) variants. We replicated the enrichment in rare predicted LOF (pLOF) variants at 13 influenza susceptibility loci involved in TLR3-dependent type I IFN immunity (OR=3.70[95%CI 1.3-8.2], P=2.1x10(-4)). This enrichment was further strengthened by (1) adding the recently reported TYK2 and TLR7 COVID-19 loci, particularly under a recessive model (OR=19.65[95%CI 2.1-2635.4], P=3.4x10(-3)), and (2) considering as pLOF branchpoint variants with potentially strong impacts on splicing among the 15 loci (OR=4.40[9%CI 2.3-8.4], P=7.7x10(-8)). Finally, the patients with pLOF/bLOF variants at these 15 loci were significantly younger (mean age [SD]=43.3 [20.3] years) than the other patients (56.0 [17.3] years; P=1.68x10(-5)).ConclusionsRare variants of TLR3- and TLR7-dependent type I IFN immunity genes can underlie life-threatening COVID-19, particularly with recessive inheritance, in patients under 60 years old

    Global fertility in 204 countries and territories, 1950–2021, with forecasts to 2100: a comprehensive demographic analysis for the Global Burden of Disease Study 2021

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    BackgroundAccurate assessments of current and future fertility—including overall trends and changing population age structures across countries and regions—are essential to help plan for the profound social, economic, environmental, and geopolitical challenges that these changes will bring. Estimates and projections of fertility are necessary to inform policies involving resource and health-care needs, labour supply, education, gender equality, and family planning and support. The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 produced up-to-date and comprehensive demographic assessments of key fertility indicators at global, regional, and national levels from 1950 to 2021 and forecast fertility metrics to 2100 based on a reference scenario and key policy-dependent alternative scenarios. MethodsTo estimate fertility indicators from 1950 to 2021, mixed-effects regression models and spatiotemporal Gaussian process regression were used to synthesise data from 8709 country-years of vital and sample registrations, 1455 surveys and censuses, and 150 other sources, and to generate age-specific fertility rates (ASFRs) for 5-year age groups from age 10 years to 54 years. ASFRs were summed across age groups to produce estimates of total fertility rate (TFR). Livebirths were calculated by multiplying ASFR and age-specific female population, then summing across ages 10–54 years. To forecast future fertility up to 2100, our Institute for Health Metrics and Evaluation (IHME) forecasting model was based on projections of completed cohort fertility at age 50 years (CCF50; the average number of children born over time to females from a specified birth cohort), which yields more stable and accurate measures of fertility than directly modelling TFR. CCF50 was modelled using an ensemble approach in which three sub-models (with two, three, and four covariates variously consisting of female educational attainment, contraceptive met need, population density in habitable areas, and under-5 mortality) were given equal weights, and analyses were conducted utilising the MR-BRT (meta-regression—Bayesian, regularised, trimmed) tool. To capture time-series trends in CCF50 not explained by these covariates, we used a first-order autoregressive model on the residual term. CCF50 as a proportion of each 5-year ASFR was predicted using a linear mixed-effects model with fixed-effects covariates (female educational attainment and contraceptive met need) and random intercepts for geographical regions. Projected TFRs were then computed for each calendar year as the sum of single-year ASFRs across age groups. The reference forecast is our estimate of the most likely fertility future given the model, past fertility, forecasts of covariates, and historical relationships between covariates and fertility. We additionally produced forecasts for multiple alternative scenarios in each location: the UN Sustainable Development Goal (SDG) for education is achieved by 2030; the contraceptive met need SDG is achieved by 2030; pro-natal policies are enacted to create supportive environments for those who give birth; and the previous three scenarios combined. Uncertainty from past data inputs and model estimation was propagated throughout analyses by taking 1000 draws for past and present fertility estimates and 500 draws for future forecasts from the estimated distribution for each metric, with 95% uncertainty intervals (UIs) given as the 2·5 and 97·5 percentiles of the draws. To evaluate the forecasting performance of our model and others, we computed skill values—a metric assessing gain in forecasting accuracy—by comparing predicted versus observed ASFRs from the past 15 years (2007–21). A positive skill metric indicates that the model being evaluated performs better than the baseline model (here, a simplified model holding 2007 values constant in the future), and a negative metric indicates that the evaluated model performs worse than baseline. FindingsDuring the period from 1950 to 2021, global TFR more than halved, from 4·84 (95% UI 4·63–5·06) to 2·23 (2·09–2·38). Global annual livebirths peaked in 2016 at 142 million (95% UI 137–147), declining to 129 million (121–138) in 2021. Fertility rates declined in all countries and territories since 1950, with TFR remaining above 2·1—canonically considered replacement-level fertility—in 94 (46·1%) countries and territories in 2021. This included 44 of 46 countries in sub-Saharan Africa, which was the super-region with the largest share of livebirths in 2021 (29·2% [28·7–29·6]). 47 countries and territories in which lowest estimated fertility between 1950 and 2021 was below replacement experienced one or more subsequent years with higher fertility; only three of these locations rebounded above replacement levels. Future fertility rates were projected to continue to decline worldwide, reaching a global TFR of 1·83 (1·59–2·08) in 2050 and 1·59 (1·25–1·96) in 2100 under the reference scenario. The number of countries and territories with fertility rates remaining above replacement was forecast to be 49 (24·0%) in 2050 and only six (2·9%) in 2100, with three of these six countries included in the 2021 World Bank-defined low-income group, all located in the GBD super-region of sub-Saharan Africa. The proportion of livebirths occurring in sub-Saharan Africa was forecast to increase to more than half of the world's livebirths in 2100, to 41·3% (39·6–43·1) in 2050 and 54·3% (47·1–59·5) in 2100. The share of livebirths was projected to decline between 2021 and 2100 in most of the six other super-regions—decreasing, for example, in south Asia from 24·8% (23·7–25·8) in 2021 to 16·7% (14·3–19·1) in 2050 and 7·1% (4·4–10·1) in 2100—but was forecast to increase modestly in the north Africa and Middle East and high-income super-regions. Forecast estimates for the alternative combined scenario suggest that meeting SDG targets for education and contraceptive met need, as well as implementing pro-natal policies, would result in global TFRs of 1·65 (1·40–1·92) in 2050 and 1·62 (1·35–1·95) in 2100. The forecasting skill metric values for the IHME model were positive across all age groups, indicating that the model is better than the constant prediction. InterpretationFertility is declining globally, with rates in more than half of all countries and territories in 2021 below replacement level. Trends since 2000 show considerable heterogeneity in the steepness of declines, and only a small number of countries experienced even a slight fertility rebound after their lowest observed rate, with none reaching replacement level. Additionally, the distribution of livebirths across the globe is shifting, with a greater proportion occurring in the lowest-income countries. Future fertility rates will continue to decline worldwide and will remain low even under successful implementation of pro-natal policies. These changes will have far-reaching economic and societal consequences due to ageing populations and declining workforces in higher-income countries, combined with an increasing share of livebirths among the already poorest regions of the world. FundingBill & Melinda Gates Foundation
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