Photofermentative production of hydrogen and poly-β-hydroxybutyrate from dark fermentation products

The aim of this work is to investigate the hydrogen and poly-β-hydroxybutyrate (PHB) production during the photofermentative treatment of the effluent from a dark fermentation reactor fed with the organic fraction of municipal solid waste. Two different inocula, an adapted culture of Rhodobacter sphaeroides AV1b and a mixed consortium of purple non sulphur bacteria have been investigated under the same operational conditions. Different hydrogen productivities of 364 and 559NmL H2 L(-1) were observed for the Rhodobacter sphaeroides and the mixed culture consortium tests, respectively: the consortium of PNSB resulted 1.5-fold more productive than the pure culture. On the other hand, Rhodobacter sphaeroides culture showed a higher PHB productivity (155mg PHB g COD(-1)) than the mixed culture (55mg PHB g COD(-1)). In all the tests, the concomitant H2 and PHB production was associated to a dissolved COD removal higher than 80%

Assessing the climate resilience of community-managed water supplies in Ethiopia and Nepal

Understanding the resilience of water supplies to climate change is becoming an urgent priority to ensure health targets are met. Addressing systemic issues and building the resilience of community-managed supplies, which serve millions of people in rural LMIC settings, will be critical to improve access to safe drinking water. The How Tough is WASH (HTIW) framework to assess resilience was applied to community-managed water supplies in Ethiopia and Nepal to assess the effectiveness of this framework in field conditions. The resilience of these water supplies was measured along six domains—the environment, infrastructure, management, institutional support, community governance and supply chains—that can affect how they respond to climate change effects. We found that the HTIW framework provided an objective measure of resilience and could be used to rank water supplies in order of priority for action. We also found that systemic issues could be identified. The tools and methods used in the framework were easy to deploy by field research teams. The water supplies studied in Ethiopia and Nepal had low to moderate resilience to climate change. Service management and institutional support were weak in both countries. The data from Ethiopia and Nepal suggests that many water supplies in rural and small-town communities are unlikely to be resilient to future climate change without increased investment and support. The use of simple frameworks such as HTIW will be important in supporting decisions around such investments by identifying priority communities and actions

Revising the dark fermentative H2 research and development scenario – An overview of the recent advances and emerging technological approaches

The indiscriminate use of fossil fuels has led to several challenges such as greenhouse gas emissions, environmental degradation, and energy security. Establishment of clean fuels is at the forefront of science and innovation in today’s society to curb these problems. Dark fermentation (DF) is widely regarded as the most promising clean energy technology of the 21st century due to its desirable properties such as high energy content, its non-polluting features, its ability to use a broad spectrum of feedstocks and inoculum sources, as well as its ability to use mild fermentation conditions. In developing nations, this technology could be instrumental in establishing effective waste disposal systems while boosting the production of clean fuels. However, DF is still hindered by the low yields which stagnate its commercialization. This paper reviews the recent and emerging technologies that are gaining prominence in DF based on information that has been gathered from recent scientific publications. Herein, novel enhancement methods such as cell immobilization, nanotechnology, mathematical optimization tools, and technologies for biogas upgrading using renewable H2 are comprehensively discussed. Furthermore, a section which discusses the potential of bioenergy in Sub-Saharan Africa including South Africa is included. Finally, scientific areas that need further research and development in DF process are also presented

Global burden of 288 causes of death and life expectancy decomposition in 204 countries and territories and 811 subnational locations, 1990–2021: a systematic analysis for the Global Burden of Disease Study 2021

BACKGROUND Regular, detailed reporting on population health by underlying cause of death is fundamental for public health decision making. Cause-specific estimates of mortality and the subsequent effects on life expectancy worldwide are valuable metrics to gauge progress in reducing mortality rates. These estimates are particularly important following large-scale mortality spikes, such as the COVID-19 pandemic. When systematically analysed, mortality rates and life expectancy allow comparisons of the consequences of causes of death globally and over time, providing a nuanced understanding of the effect of these causes on global populations. METHODS The Global Burden of Diseases, Injuries, and Risk Factors Study (GBD) 2021 cause-of-death analysis estimated mortality and years of life lost (YLLs) from 288 causes of death by age-sex-location-year in 204 countries and territories and 811 subnational locations for each year from 1990 until 2021. The analysis used 56 604 data sources, including data from vital registration and verbal autopsy as well as surveys, censuses, surveillance systems, and cancer registries, among others. As with previous GBD rounds, cause-specific death rates for most causes were estimated using the Cause of Death Ensemble model-a modelling tool developed for GBD to assess the out-of-sample predictive validity of different statistical models and covariate permutations and combine those results to produce cause-specific mortality estimates-with alternative strategies adapted to model causes with insufficient data, substantial changes in reporting over the study period, or unusual epidemiology. YLLs were computed as the product of the number of deaths for each cause-age-sex-location-year and the standard life expectancy at each age. As part of the modelling process, uncertainty intervals (UIs) were generated using the 2·5th and 97·5th percentiles from a 1000-draw distribution for each metric. We decomposed life expectancy by cause of death, location, and year to show cause-specific effects on life expectancy from 1990 to 2021. We also used the coefficient of variation and the fraction of population affected by 90% of deaths to highlight concentrations of mortality. Findings are reported in counts and age-standardised rates. Methodological improvements for cause-of-death estimates in GBD 2021 include the expansion of under-5-years age group to include four new age groups, enhanced methods to account for stochastic variation of sparse data, and the inclusion of COVID-19 and other pandemic-related mortality-which includes excess mortality associated with the pandemic, excluding COVID-19, lower respiratory infections, measles, malaria, and pertussis. For this analysis, 199 new country-years of vital registration cause-of-death data, 5 country-years of surveillance data, 21 country-years of verbal autopsy data, and 94 country-years of other data types were added to those used in previous GBD rounds. FINDINGS The leading causes of age-standardised deaths globally were the same in 2019 as they were in 1990; in descending order, these were, ischaemic heart disease, stroke, chronic obstructive pulmonary disease, and lower respiratory infections. In 2021, however, COVID-19 replaced stroke as the second-leading age-standardised cause of death, with 94·0 deaths (95% UI 89·2-100·0) per 100 000 population. The COVID-19 pandemic shifted the rankings of the leading five causes, lowering stroke to the third-leading and chronic obstructive pulmonary disease to the fourth-leading position. In 2021, the highest age-standardised death rates from COVID-19 occurred in sub-Saharan Africa (271·0 deaths [250·1-290·7] per 100 000 population) and Latin America and the Caribbean (195·4 deaths [182·1-211·4] per 100 000 population). The lowest age-standardised death rates from COVID-19 were in the high-income super-region (48·1 deaths [47·4-48·8] per 100 000 population) and southeast Asia, east Asia, and Oceania (23·2 deaths [16·3-37·2] per 100 000 population). Globally, life expectancy steadily improved between 1990 and 2019 for 18 of the 22 investigated causes. Decomposition of global and regional life expectancy showed the positive effect that reductions in deaths from enteric infections, lower respiratory infections, stroke, and neonatal deaths, among others have contributed to improved survival over the study period. However, a net reduction of 1·6 years occurred in global life expectancy between 2019 and 2021, primarily due to increased death rates from COVID-19 and other pandemic-related mortality. Life expectancy was highly variable between super-regions over the study period, with southeast Asia, east Asia, and Oceania gaining 8·3 years (6·7-9·9) overall, while having the smallest reduction in life expectancy due to COVID-19 (0·4 years). The largest reduction in life expectancy due to COVID-19 occurred in Latin America and the Caribbean (3·6 years). Additionally, 53 of the 288 causes of death were highly concentrated in locations with less than 50% of the global population as of 2021, and these causes of death became progressively more concentrated since 1990, when only 44 causes showed this pattern. The concentration phenomenon is discussed heuristically with respect to enteric and lower respiratory infections, malaria, HIV/AIDS, neonatal disorders, tuberculosis, and measles. INTERPRETATION Long-standing gains in life expectancy and reductions in many of the leading causes of death have been disrupted by the COVID-19 pandemic, the adverse effects of which were spread unevenly among populations. Despite the pandemic, there has been continued progress in combatting several notable causes of death, leading to improved global life expectancy over the study period. Each of the seven GBD super-regions showed an overall improvement from 1990 and 2021, obscuring the negative effect in the years of the pandemic. Additionally, our findings regarding regional variation in causes of death driving increases in life expectancy hold clear policy utility. Analyses of shifting mortality trends reveal that several causes, once widespread globally, are now increasingly concentrated geographically. These changes in mortality concentration, alongside further investigation of changing risks, interventions, and relevant policy, present an important opportunity to deepen our understanding of mortality-reduction strategies. Examining patterns in mortality concentration might reveal areas where successful public health interventions have been implemented. Translating these successes to locations where certain causes of death remain entrenched can inform policies that work to improve life expectancy for people everywhere. FUNDING Bill & Melinda Gates Foundation

Production par fermentation sombre de biohydrogène à partir de déchets organiques et valorisation des sous-produits dans un concept de bioraffinerie

Low biohydrogen (H2) yields and use of process by-products from dark fermentation (DF) of waste biomass is limiting its scaled-up application. This study aims to investigate the effects of culture pH, combination of substrate concentration and culture pH, pre-treatment of substrate and inoculum adaptation in H2 yields during the DF of three different wastes biomass. The study showed that the biodegradability of the substrates is important for the selection and application of optimum operational parameters aimed at enhancing H2 production. Moreover, long-term operational feasibility and stability of dark fermentative H2 production was demostrated using food waste and cheese whey in two semi-continuous thermophilic DF reactors. The effect of organic loading rates (OLRs), hydraulic retention times (HRTs) and co-substrates (buffalo manure) addition as a source of alkalinity on culture pH and H2 production stability was discussed. The study showed that combination of OLR, HRT and co-substrate addition could play an important role in the culture pH and stability of H2 production. Furthermore, the by-products of DF process was utilized for H2 production via photo fermentation (PF), while the waste stream generated from coupling of DF and PF processes was converted to methane in anaerobic digestion (AD). The three-step conversion of food waste in a biorefinery concept increased the total energy yields. Moreover, PF also showed a good potential for concomitant production of H2 and polyhydroxybutyrate (biopolymer). Likewise, dry fermentation could be promising to a biorefinery concept based on waste biomass for the production of bioenergy and biochemicals (organic acids and alcohols)La fermentation sombre est un procédé utilisant des déchets organiques dont le passage à l'échelle pilote est limité par les rendements de production d'hydrogène trop faibles ainsi que par l'utilisation des sous-produits. Cette étude a pour premier objectif d'étudier l'effet du pH, de la combinaison du pH et de la concentration en substrat, du prétraitement du substrat et de l'adaptation de l'inoculum sur la fermentation sombre de trois types de déchet différents. Il a notamment été montré que la biodégradabilité des substrats joue un rôle majeur dans le choix des paramètres opérationnels utilisés pour optimiser la production d'hydrogène. De plus, la faisabilité et la stabilité à long terme de la production d'hydrogène par le procédé de fermentation sombre ont été mises en évidence en utilisant des déchets agroalimentaires et du petit lait dans deux réacteurs thermophiliques fonctionnant en mode semi-continu. En particulier, il a été discuté l'influence de la charge organique (OLR), du temps de rétention hydraulique (HRT) et de l'addition de co-substrats (fumier de buffle) comme source d'alcalinité. Cette étude a montré que la combinaison de ces trois paramètres peut jouer un rôle important sur le pH et la stabilité de la production d'hydrogène. De plus, les sous-produits de la fermentation sombre ont été utilisés pour produire de l'hydrogène via la photo-fermentation, alors que les déchets générés par le couplage de la fermentation sombre et de la photo-fermentation ont été valorisés pour la production de méthane par digestion anaérobie. Ce concept de bioraffinerie basé sur la conversion en trois étapes des déchets agroalimentaires augmente le rendement énergétique global du procédé. Par ailleurs, il a été montré le potentiel important du procédé de photo-fermentation pour la production de polyhydroxybutyrate (polymère), parallèlement à celle d'hydrogène. De même, l'utilisation de la fermentation par voie sèche dans une bioraffinerie concept apparaît prometteuse vis à vis de la production de bioénergie et de molécules telles que les acides organiques et les alcool

OPTIMIZATION OF ASYMMETRIC MANY-CORE SYSTEMS

In this modern computing world, with the advancement in technology, many-core systems are accelerating towards the emerging heterogeneous architecture. Optimization of the application performance is a crucial task for the unexplored aspect of design space exploration. Different research approaches have been proposed regarding the improvement in the efficiency of AMP(asymmetric many-core processor) with the adjustment to the diversity in workloads. In this respect, prediction of workload performance is very important for run-time optimization techniques. This is the reason we address the approach to consider the trade-offs exploration for the architectural simulation in our work. This approach can be followed by providing a feasible scenario with the design space parameters for the architectural exploration. Machine learning, along with the transfer learning technique, is taken into consideration to build the performance model for the prediction