Electrolysis feels the heat
Electricity infrastructure powered by sunlight and wind requires flexible storage capacity to compensate for the intermittency of these sources. In this context, Hauch
et ...al.
review progress in solid oxide electrolyzer technology to split water and/or carbon dioxide into chemical fuels. These devices, which rely on oxide conduction between cathode and anode, use nonprecious metals as catalysts and operate above 600°C, thereby benefiting from thermodynamic and kinetic efficiencies. The authors highlight recent optimizations of cell components as well as systems-level architecture.
Science
, this issue p.
eaba6118
BACKGROUND
Alleviating the worst effects of climate change requires drastic modification of our energy system: moving from fossil fuels to low-carbon energy sources. The challenge is not the amount of renewable energy available—energy potential from solar and wind exceeds global energy consumption many times over. Rather, the key to a 100% renewable energy supply lies in the integration of the growing share of intermittent sources into a power infrastructure that can meet continuous demand. The higher the share of renewables, the more flexible and interconnected the energy system (the electric grid, the gas and heat networks, etc.) needs to be. Critically, a future energy system where the supply of electricity, heat, and fuels is based solely on renewables relies heavily on technologies capable of converting electricity into chemicals and fuels suitable for heavy transport at high efficiencies. In addition, higher electrolysis efficiency and integrated fuel production can decrease the reliance on bioenergy further than conventional electrolysis can.
ADVANCES
Electrolysis is the core technology of power-to-X (PtX) solutions, where X can be hydrogen, syngas, or synthetic fuels. When electrolysis is combined with renewable electricity, the production of fuels and chemicals can be decoupled from fossil resources, paving the way for an energy system based on 100% renewable energy. Solid oxide electrolysis cell (SOEC) technology is attractive because of unrivaled conversion efficiencies—a result of favorable thermodynamics and kinetics at higher operating temperatures. SOECs can be used for direct electrochemical conversion of steam (H
2
O), carbon dioxide (CO
2
), or both into hydrogen (H
2
), carbon monoxide (CO), or syngas (H
2
+CO), respectively. SOECs can be thermally integrated with a range of chemical syntheses, enabling recycling of captured CO
2
and H
2
O into synthetic natural gas or gasoline, methanol, or ammonia, resulting in further efficiency improvements compared with low-temperature electrolysis technologies. SOEC technology has undergone tremendous development and improvements over the past 10 to 15 years. The initial electrochemical performance of state-of-the-art SOEC single cells has more than doubled, while long-term durability has been improved by a factor of ∼100. Similar improvements in performance and durability have been achieved on the stack level. Furthermore, SOEC technology is based on scalable production methods and abundant raw materials such as nickel, zirconia, and steel, not precious metals. Performance and durability improvements as well as increased scale-up efforts have led to a hundredfold gas production capacity increase within the past decade and to commissioning of the first industrially relevant SOEC plants. Over the next 2 to 3 years, plant size is expected to further increase by a factor of almost 20. In recent years, SOEC systems have been integrated with downstream synthesis processes: examples include a demonstration plant for upgrading of biogas to pipeline quality methane and the use of syngas from an SOEC plant to produce fuels for transport via the Fischer-Tropsch process.
OUTLOOK
Improved understanding of the nanoscale processes occurring in SOECs will continue to result in performance and lifetime gains on the cell, stack, and system levels, which in turn will enable even larger and more efficient SOEC plants. In Germany, the share of intermittent renewables in the electricity supply has passed 30%, while in Denmark, intermittent sources account for almost 50% of the electricity supply. As this happens for a growing number of countries, demand for efficient energy conversion technologies such as SOECs is poised to increase. The increasing scale will help bring down production costs, thereby making SOECs cost-competitive with other electrolysis technologies and, given sufficiently high CO
2
emissions taxation, cost-competitive with fossil-based methods for producing H
2
and CO. SOECs offer an opportunity to decrease the costs of future renewable energy systems through more efficient conversion and enable further integration of renewables into the energy mix.
Solid oxide electrolyzers: From nanoscale to macroscale.
The splitting of H
2
O or CO
2
occurs at solid oxide electrolysis cell (SOEC) electrodes. Multiple cells are combined into SOEC stacks, which are in turn combined into SOEC plants. When renewable electricity is used, the production of transport fuels and chemicals can be decoupled from fossil resources. SOECs operate at elevated temperatures, resulting in electrolysis efficiencies unattainable by other electrolysis technologies.
In a world powered by intermittent renewable energy, electrolyzers will play a central role in converting electrical energy into chemical energy, thereby decoupling the production of transport fuels and chemicals from today’s fossil resources and decreasing the reliance on bioenergy. Solid oxide electrolysis cells (SOECs) offer two major advantages over alternative electrolysis technologies. First, their high operating temperatures result in favorable thermodynamics and reaction kinetics, enabling unrivaled conversion efficiencies. Second, SOECs can be thermally integrated with downstream chemical syntheses, such as the production of methanol, dimethyl ether, synthetic fuels, or ammonia. SOEC technology has witnessed tremendous improvements during the past 10 to 15 years and is approaching maturity, driven by advances at the cell, stack, and system levels.
The Integrative Psychiatric Research (iPSYCH) consortium has established a large Danish population-based Case-Cohort sample (iPSYCH2012) aimed at unravelling the genetic and environmental ...architecture of severe mental disorders. The iPSYCH2012 sample is nested within the entire Danish population born between 1981 and 2005, including 1 472 762 persons. This paper introduces the iPSYCH2012 sample and outlines key future research directions. Cases were identified as persons with schizophrenia (N=3540), autism (N=16 146), attention-deficit/hyperactivity disorder (N=18 726) and affective disorder (N=26 380), of which 1928 had bipolar affective disorder. Controls were randomly sampled individuals (N=30 000). Within the sample of 86 189 individuals, a total of 57 377 individuals had at least one major mental disorder. DNA was extracted from the neonatal dried blood spot samples obtained from the Danish Neonatal Screening Biobank and genotyped using the Illumina PsychChip. Genotyping was successful for 90% of the sample. The assessments of exome sequencing, methylation profiling, metabolome profiling, vitamin-D, inflammatory and neurotrophic factors are in progress. For each individual, the iPSYCH2012 sample also includes longitudinal information on health, prescribed medicine, social and socioeconomic information, and analogous information among relatives. To the best of our knowledge, the iPSYCH2012 sample is the largest and most comprehensive data source for the combined study of genetic and environmental aetiologies of severe mental disorders.
Background: Conflicting findings have been reported on the association between smoking and the risk of venous thromboembolism (VTE).
Objectives: To conduct a prospective, population‐based cohort ...study to investigate the association between cigarette smoking and the risk of incident VTE.
Patients/Methods: Information on smoking habits was assessed by self‐administered questionnaires in 24 576 subjects, aged 25–96 years, participating in the fourth Tromsø Study in 1994–1995. Incident cases of VTE were registered until the end of follow‐up at 1 September 2007.
Results: A total of 389 incident VTE events (1.61 per 1000 person‐years) were registered during follow‐up (median of 12.5 years). Heavy smokers (> 20 pack‐years) had a hazard ratio (HR) of 1.46 (95% confidence interval CI 1.04–2.05) for total VTE, and and an HR of 1.75 (95% CI 1.14–2.69) for provoked VTE, as compared with never smokers. The risk of provoked VTE increased with more pack‐years of smoking (P = 0.02). Smoking was not associated with risk of unprovoked VTE. The number of pack‐years was associated with increased risk of cancer and myocardial infarction, whereas the association between pack‐years of smoking and VTE disappeared when failure times were censored at the occurrence of cancer or myocardial infarction.
Conclusions: Heavy smoking was apparently a risk factor for provoked VTE in analyses with VTE events as the only outcome. The lack of association between smoking and risk of VTE in analyses censored at the occurrence of cancer or myocardial infarction may suggest that smoking‐attributable diseases or other predisposing factors are essential for smoking to convey a risk of VTE.
Essentials
Discovery of predictive biomarkers of venous thromboembolism (VTE) may aid risk stratification.
A case‐control study where plasma was sampled before the occurrence of VTE was established.
...We generated untargeted plasma proteomic profiles of 200 individuals by use of mass spectrometry.
Assessment of the biomarker potential of 501 proteins yielded 46 biomarker candidates.
Background
Prophylactic anticoagulant treatment may substantially reduce the incidence of venous thromboembolism (VTE) but entails considerable risk of severe bleeding. Identification of individuals at high risk of VTE through the use of predictive biomarkers is desirable in order to achieve a favorable benefit‐to‐harm ratio.
Objective
We aimed to identify predictive protein biomarker candidates of VTE.
Methods
We performed a case‐control study of 200 individuals that participated in the Tromsø Study, a population‐based cohort, where blood samples were collected before the VTE events occurred. Untargeted tandem mass tag‐synchronous precursor selection‐mass spectrometry (TMT‐SPS‐MS3)‐based proteomic profiling was used to study the plasma proteomes of each individual.
Results
Of the 501 proteins detected in a sufficient number of samples to allow multivariate analysis, 46 proteins were associated with VTE case–control status with P‐values below the 0.05 significance threshold. The strongest predictive biomarker candidates, assessed by statistical significance, were transthyretin, vitamin K‐dependent protein Z and protein/nucleic acid deglycase DJ‐1.
Conclusions
Our untargeted approach of plasma proteome profiling revealed novel predictive biomarker candidates of VTE and confirmed previously reported candidates, thereby providing conceptual support for the validity of the study. A larger nested case–control study will be conducted to validate our findings.
Abstract
This review gives first a brief view of the potential availability of sustainable energy. It is clear that over 100 times more solar photovoltaic energy than necessary is readily accessible ...and that practically available wind alone may deliver sufficient energy supply to the world. Due to the intermittency of these sources, effective and inexpensive energy-conversion and storage technology is needed. Motivation for the possible electrolysis application of reversible solid-oxide cells (RSOCs), including a comparison of power-to-fuel/fuel-to-power to other energy-conversion and storage technologies is presented. RSOC electrochemistry and chemistry of H2O, CO2, H2, CO, CnHm (hydrocarbons) and NH3, including thermodynamics and cell performance, are described. The mechanical strength of popular cell supports is outlined, and newly found stronger materials are mentioned. Common cell-degradation mechanisms, including the effect of common impurities in gases and materials (such as S and Si), plus the deleterious effects of carbon deposition in the fuel electrode are described followed by explanations of how to avoid or ease the consequences. Visions of how RSOCs powered by sustainable energy may be applied on a large scale for the transportation sector via power-to-fuel technology and for integration with the electrical grid together with seasonal storage are presented. Finally, a brief comparison of RSOCs to other electrolysis cells and an outlook with examples of actions necessary to commercialize RSOC applications are sketched.
On 17 August 2017, gravitational waves (GWs) were detected from a binary neutron star merger, GW170817, along with a coincident short gamma-ray burst, GRB 170817A. An optical transient source, Swope ...Supernova Survey 17a (SSS17a),was subsequently identified as the counterpart of this event. We present ultraviolet, optical, and infrared light curves of SSS17a extending from 10.9 hours to 18 days postmerger. We constrain the radioactively powered transient resulting from the ejection of neutron-rich material. The fast rise of the light curves, subsequent decay, and rapid color evolution are consistent with multiple ejecta components of differing lanthanide abundance. The late-time light curve indicates that SSS17a produced at least ~0.05 solar masses of heavy elements, demonstrating that neutron star mergers play a role in rapid neutron capture (r-process) nucleosynthesis in the universe.
Essentials
Reports on recurrence and mortality after a first venous thromboembolism (VTE) vary considerably.
We describe rates of recurrence and mortality in patients with a first VTE from the Tromsø ...study.
The overall recurrence rate was 3.9 per 100 person‐years, but this varied widely with time.
Despite advances in VTE management, the rates of adverse events are still fairly high.
Summary
Background
Previous reports on recurrence and mortality rates after a first episode of venous thromboembolism (VTE) vary considerably. Advances in the management and treatment of VTE during the last 15 years may have influenced the rates of clinical outcomes.
Aim
To estimate the rates of recurrence and mortality after a first VTE in patients recruited from a large population‐based cohort.
Method
From the Tromsø study, patients (n = 710) with a first, symptomatic, objectively confirmed VTE were included and followed in the period 1994–2012. Recurrent episodes of VTE were identified from multiple sources and carefully validated by review of medical records. Incidence rates and cumulative incidence rates with 95% confidence intervals (CIs) of VTE recurrence and mortality were calculated.
Results
The mean age of the patients was 68 years (range 28–102 years), and 166 (23.4%) had cancer at the time of first VTE. There were 114 VTE recurrences and 333 deaths during a median study period of 7.7 years (range 0.04–18.2 years). The risk of recurrence was highest during the first year. The overall 1‐year recurrence rate was 7.8 (95% CI 5.8–10.6) per 100 person‐years (PY), whereas the recurrence rate in the remaining follow‐up period (1–18 years) was 3.0 (95% CI 2.4–3.8) per 100 PY. The overall 1‐year all‐cause mortality rate was 29.9 (95% CI 25.7–34.8) per 100 PY, and in those without cancer the corresponding rate was 23.6 (95% CI 17.8–31.3) per 100 PY.
Conclusion
Despite advances in VTE management, the rates of adverse events remained fairly high, particularly in the first year following a first VTE.
Next‐generation sequencing and the collection of genome‐wide data allow identifying adaptive variation and footprints of directional selection. Using a large SNP data set from 259 RAD‐sequenced ...European eel individuals (glass eels) from eight locations between 34 and 64ᵒN, we examined the patterns of genome‐wide genetic diversity across locations. We tested for local selection by searching for increased population differentiation using FST‐based outlier tests and by testing for significant associations between allele frequencies and environmental variables. The overall low genetic differentiation found (FST = 0.0007) indicates that most of the genome is homogenized by gene flow, providing further evidence for genomic panmixia in the European eel. The lack of genetic substructuring was consistent at both nuclear and mitochondrial SNPs. Using an extensive number of diagnostic SNPs, results showed a low occurrence of hybrids between European and American eel, mainly limited to Iceland (5.9%), although individuals with signatures of introgression several generations back in time were found in mainland Europe. Despite panmixia, a small set of SNPs showed high genetic differentiation consistent with single‐generation signatures of spatially varying selection acting on glass eels. After screening 50 354 SNPs, a total of 754 potentially locally selected SNPs were identified. Candidate genes for local selection constituted a wide array of functions, including calcium signalling, neuroactive ligand–receptor interaction and circadian rhythm. Remarkably, one of the candidate genes identified is PERIOD, possibly related to differences in local photoperiod associated with the >30° difference in latitude between locations. Genes under selection were spread across the genome, and there were no large regions of increased differentiation as expected when selection occurs within just a single generation due to panmixia. This supports the conclusion that most of the genome is homogenized by gene flow that removes any effects of diversifying selection from each new generation.
Growing evidence supports a role for extracellular vesicles (EVs) in haemostasis and thrombosis due to exposure of negatively charged procoagulant phospholipids (PPL). Current commercial ...PPL-dependent clotting assays use chemically phospholipid depleted plasma to measure PPL activity. The purpose of our study was to modify the PPL assay by substituting the chemically phospholipid depleted plasma with PPL depleted plasma obtained by ultracentrifugation This in order to get readily access to a sensitive and reliable assay to measure PPL activity in human plasma and cell supernatants. The performance of the assay was tested, including the influence of individual coagulation factors and postprandial lipoproteins and compared to a commercial PPL assay (STA-Procoag-PPL). The two PPL assays displayed similar sensitivity to exogenously added standardized phospholipids. The PPL activity measured by the modified assay strongly correlates with the results from the commercial assay. The intraday- and between-days coefficients of variation ranged from 2-4% depending on the PPL activity in the sample. The modified PPL assay was insensitive to postprandial lipoprotein levels in plasma, as well as to tissue factor (TF) positive EVs from stimulated whole blood. Our findings showed that the modified assay performed equal to the comparator, and was insensitive to postprandial lipoproteins and TF
EVs.
Essentials
Registry‐based studies indicate a link between arterial‐ and venous thromboembolism (VTE).
We studied this association in a cohort with confounder information and validated outcomes.
...Myocardial infarction (MI) was associated with a 4.8‐fold increased short‐term risk of VTE.
MI was associated with a transient increased risk of VTE, and pulmonary embolism in particular.
Summary
Background
Recent studies have demonstrated an association between venous thromboembolism (VTE) and arterial thrombotic diseases.
Objectives
To study the association between incident myocardial infarction (MI) and VTE in a prospective population‐based cohort.
Methods
Study participants (n = 29 506) were recruited from three surveys of the Tromsø Study (conducted in 1994–1995, 2001–2002, and 2007–2008) and followed up to 2010. All incident MI and VTE events during follow‐up were recorded. Cox regression models with age as the time scale and MI as a time‐dependent variable were used to calculate hazard ratios (HRs) of VTE adjusted for sex, body mass index, blood pressure, diabetes mellitus, HDL cholesterol, smoking, physical activity, and education level.
Results
During a median follow‐up of 15.7 years, 1853 participants experienced an MI and 699 experienced a VTE. MI was associated with a 51% increased risk of VTE (HR 1.51; 95% confidence interval CI 1.08–2.10) and a 72% increased risk of pulmonary embolism (PE) (HR 1.72; 95% CI 1.07–2.75), but not significantly associated with the risk of deep vein thrombosis (DVT) (HR 1.36; 95% CI 0.86–2.15). The highest risk estimates for PE were observed during the first 6 months after the MI (HR 8.49; 95% CI 4.00–18.77). MI explained 6.2% of the PEs in the population (population attributable risk) and 78.5% of the PE risk in MI patients (attributable risk).
Conclusions
Our findings indicate that MI is associated with a transient increased VTE risk, independently of traditional atherosclerotic risk factors. The risk estimates were particularly high for PE.
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