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As economic activity in marine environments accelerates and expands, conflicts may increase following increased demand over marine resources, unequal distribution of benefits, as well as fluctuating resource availability and quality due to climate change. Anticipation and resolution of these conflicts require understanding of the causal mechanisms through which they originate and persist. Process tracing is a promising social science method that allows producing this knowledge by sequentially ordering events that produce conflict. The aim of this paper is to introduce process tracing as a method for the study of conflicts over marine environments and to assess how the method so far is used in previous studies of conflicts over marine environments. Our review of these studies reveals that scholars of conflicts over marine environments tend to apply process tracing using a deductive approach and a probabilistic understanding of causal mechanisms. The causal mechanisms that are identified to understand the dynamics that drive conflicts over marine environments often include power dynamics between states, institutions, movements or communities. Less articulated is how local social dynamics drives conflicts and how scholars select their cases to represent a wider population of conflicts. We conclude that applying a micro-sociological approach, more attention to case selection, and the interaction between contexts and mechanisms are promising ways forward for further use of process tracing in maritime studies. Correction in: Maritime Studies, vol. 22, issue 2, article number 25, DOI: 10.1007/s40152-023-00314-4

The death of a parent during childhood is a major traumatic event. While there is a good understanding of the early-life effects of parental loss, the evidence regarding its impact on adult mortali...

Migration played a central role in industrialisation by reallocating labour from the countryside to urban areas and centres of manufacturing where it was in high demand, and better remunerated, with implications for economic growth and individual well-being. We investigate the labour market performance of internal migrants in Sweden around the turn of the last century; a period of industrialisation and increasing migration. We add to the literature in two ways: first by focusing on earnings instead of occupational attainment; second by extending the scope beyond the prevailing focus on men by also considering women. To assess how migrants fared compared to locals, we use detailed matched firm-individual data covering three manufacturing industries which varied in terms of production, organisation, and composition of the workforce. We find that migrants, irrespective of gender, performed well in that their earnings were higher than those of locals in general and of co-workers in the same firm. These premia are consistent with a Roy model in which migrants’ sort into locations where returns to skills match individual ability. An increase in both hours worked and effort further explains the observed earnings premium among female migrants. (Less)

Trace-metal contamination poses a threat to performance and stability of proton exchange membrane fuel cells (PEMFCs). In this study the source of origin and degree of metal dissolution from carbon-coated 316L bipolar plates (BPPs) are evaluated after a long-term PEMFC test run under conditions resembling a real-life automotive application. Despite intact carbon-coating, metal dissolution occurs from uncoated oxycarbide stains on the plates’ surface. Which correlates with post-mortem detection of chromium, iron and nickel in the membrane electrode assembly. The rate of cell voltage decrease throughout the high current operations is found to be twice as high in the presence of metal ions. Metal dissolution can be correlated with transients in cell voltage during dynamic current load cycling as a result of temporary global fuel starvation. The observed difference in metal dissolution on the anode and cathode BPP indicates weak galvanic coupling between the bipolar plate(s) and the electrode layer(s).

Exposing sires to various environmental manipulations has demonstrated that paternal effects can be non-trivial also in species where male investment in offspring is almost exclusively limited to sperm. Whether paternal effects also have a genetic component (i.e. paternal indirect genetic effects (PIGEs)) in such species is however largely unknown, primarily because of methodological difficulties separating indirect from direct effects of genes. PIGEs may nevertheless be important since they have the capacity to contribute to evolutionary change. Here we use

Currently, platinum is the most widely used catalyst for low temperature proton exchange membrane fuel cells (PEMFC). However, the kinetics at the cathode are slow, and the price of platinum is high. To improve oxygen reduction reaction (ORR) kinetics at the cathode, platinum can be alloyed with rare earth elements, such as yttrium. We report that Pt3Y has the potential to be over 2 times more active for the ORR compared with Pt inside a real fuel cell. We present detailed photoemission analysis into the nature of the sputtered catalyst surface, using synchrotron radiation photoelectron spectroscopy (SRPES) to examine if surface adsorbates or impurities are present and can be removed. Pretreatment removes most of the yttrium oxide in the surface leaving behind a Pt overlayer which is only a few monolayers thick. Evidence of a substochiometric oxide peak in the Y 3d core level is presented, this oxide extends into the surface even after Ar+ sputter cleaning in-situ. This information will aid the development of new highly active nanocatalysts for employment in real fuel cell electrodes.

Four novel poly(phenylene oxide)-based anion exchange membranes were investigated for electrochemical performance, ionic conductivity and water transport properties in an operating anion exchange membrane fuel cell (AEMFC), using Pt/C gas diffusion electrodes with Tokuyama ionomer. The poly(phenylene oxide)-membranes have a 1- or 5-carbon alkyl spacer between the backbone and a trimethylalkylammonium (TMA) or piperidinium (Pip) cationic group, and ion-exchange capacities (IECs) between 1.5 and 1.9 mequiv g−1. The polymer with a 5-carbon alkyl spacer, a TMA cationic group, and a higher IEC showed the highest ion conductivity and performance in the AEMFC. The results also show that introducing a 5-carbon alkyl spacer does not improve performance unless the IEC is increased and that exchanging the TMA with a Pip cationic group results in lower fuel cell performance despite a higher IEC. A discrepancy in ion conductivity between fuel cell and ex situ test was observed for the 5-carbon spacer polymers and is attributed to a higher sensitivity for dehydration. Similar water flux under load, from the anode to the cathode with increased water content at both electrodes, was observed for all membranes and only varied with membrane thickness. The deviation in fuel cell performance observed between the membranes could not be explained by differences in water flux or ionic conduction, suggesting that the electrode–membrane interaction plays a major role. Nevertheless, the study emphasizes that high membrane conductivity (for the λ-range in a fuel cell) and efficient water transport (obtained by lower membrane thickness) promote higher electrochemical performance.

International audience; While water management in Anion Exchange Membrane Fuel Cells (AEMFCs) is seen as crucial for performance and durability, measurements of water management within operating cells remain few. In this work, we measured the performance of an H2/O2 AEMFC based on a low-density polyethylene membrane AEM, PtRu/C anode and Fe-N-C cathode for various combinations of inlet relative humidities, gas pressures and flow rates. Simultaneously, the anode and cathode outlet relative humidities were measured using humidity sensors, from which the amount of water removed from the cell could be quantified for each side. The data shows that back-diffusion of water from anode to cathode results in increasing outlet relative humidity with increased current density, both at anode and cathode. Water produced in the AEMFC was thus removed from both sides. The maximum current density was found to be strongly connected to anode flooding, which is also the main cause for hysteresis during potentiodynamic scans. However, under atypical operating conditions, the cell performance may also be limited by low humidity at the cathode, with associated low ionomer conductivity. Overall, it is concluded that water management of AEMFC with thin AEMs can be achieved by playing with both the anode and cathode operating conditions

Numerous conservation initiatives have been undertaken to protect large marine animals by legal protection and implementing marine protected areas (MPAs). Despite these efforts, many marine animals are still threatened, partly due to lack of compliance with conservation regulations. Meanwhile, research suggests that conservation efforts which also take socio-economic factors such as fishermen's livelihoods into account during planning and implementation are more likely to succeed. This study examined the compliance and socio-economic situation of local fishing communities at three sites in Indonesia (Nusa Penida, Tanjung Luar and Komodo National Park) where shark and manta ray conservation efforts have been implemented. 59 local residents were interviewed. The results showed that 49% of those residents had experienced a deterioration and 37% an improvement in their economic situation since conservation efforts in the form of species protection or MPAs were implemented in their area. The economic situation of the residents was associated with their access to alternative livelihoods, access to information on conservation rules, and relationship with conservation authorities. Particularly, interviewees with easier access to alternative income and a positive relationship with conservation authorities also experienced an increase in their economy. In addition, compliance with conservation efforts was positively related to improved economic situation, access to alternative livelihoods and information on conservation rules. These factors all differed among the three study sites, leading to different compliance levels between sites. The results of this study indicate the importance of considering socio-economic factors and of involving local communities when planning and implementing conservation efforts.

We studied the pheromone chemistry of the cerambycids Anaglyptus mysticus and Xylotrechus antilope ssp. antilope with the goal of identifying attractants that could be used as tools for pheromone-based monitoring of these two species, which are rare and red-listed in parts of northern Europe. Beetles were reared from naturally colonized branches of hazel (Corylus avellana) or oak (Quercus robur), respectively, and used for headspace sampling. The extracts of volatiles were analyzed by gas chromatography–mass spectrometry. Males of A. mysticus consistently produced large quantities of (R)-3-hydroxy-2-hexanone and 2-nonanone, minor amounts of 2,3-hexanedione, and trace amounts of six other compounds. The average proportion of 2-nonanone to (R)-3-hydroxy-2-hexanone was 70:100. Males of X. antilope produced large quantities of (S)-2-hydroxy-3-octanone, and minor quantities of 2,3-octanedione. None of these compounds were present in the corresponding extracts of females from either species. The attractiveness of the dominant compounds produced by each species was determined in field bioassays. Lures with racemic 3-hydroxy-2-hexanone and 2-nonanone as single compounds were not attractive to A. mysticus. However, the compounds acted synergistically in blends of 100:100 and 160:100 of 2-nonanone to the hydroxyketone’s (R)-enantiomer, but not in a 40:100 blend. Similarly (S)-2-hydroxy-3-octanone and its racemate attracted significantly more X. antilope than controls. Males and females of both species were captured in approximately equal numbers. The aggregation-sex pheromones of A. mysticus and X.antilope have high potential to serve as sensitive and efficient tools for detection and monitoring of local populations, and in studies of the species’ ecology and conservation requirements.

Bipolar plates (BPPs) have been identified as a key component in improving the economic viability of proton exchange membrane fuel cells (PEMFCs), as they contribute approximately 80 % of weight and 30 % of total cost in a fuel cell stack [1]. Stainless steel is considered an excellent material for mass-producing BPPs with complex flow field structures in a cost-effective manner. However, the perceived risk of corrosion and subsequent metal ion contamination as well as the inherently high contact resistance of stainless-steel surfaces have compelled manufacturers to add protective coatings to BPPs. In this study, we show new insights into the actual metal ion dissolution mechanisms in operating fuel cell systems and present experimental results which demonstrate that stainless-steel bipolar plates can be used in real life fuel cell applications without protective coatings. The bipolar plates were evaluated, in an operating fuel cell, using a dynamic load cycling protocol based on the New European Drive Cycle with increased humidity levels which simulates realistic conditions known to facilitate metal ion dissolution mechanisms [2]. The post analysis showed no signs of surface dissolution on any of the tested bipolar plates which had been subjected to the endurance/stress hybrid tests. Furthermore, only trace amounts of critical metals were found in the MEAs after testing, i.e., an order of magnitude below the radical scavenger (Mn) concentration. The trace metal contamination was comparable to a reference test without bipolar plates (graphite current collector), rendering metal input from the balance of plant the most likely source of contamination. The observable changes in cell performance and voltage degradation was unrelated to the presence of bipolar plates. A selection of experimental data is shown in Figure 1. As a theoretical explanation for the apparent stability of bare stainless-steel plates, three inter-linked phenomena were identified, akin to a three line of defence model [3]. The first and arguably most important of these phenomena is ionic decoupling between electrode and bipolar plate surface. The gas diffusion layer (GDL) strongly inhibits transport of ions from the electrode to the bipolar plate, which leads to a largely unpolarized bipolar plate and a stable surface potential even during load changes of the fuel cell. These stable potentials at the anode and cathode bipolar plates are only influenced by the immediate surroundings of the plate surfaces and are generally much milder than the encountered potentials at the electrodes. Secondly, metal dissolution from the surface of stainless steel follows a passive-transpassive-passive pattern. This mechanism describes a dissolution process, where a change in conditions at the surface, which destabilizes a previously established passive film, will only lead to limited amounts of (transpassive) metal dissolution, until a new stable passive film of different structure establishes itself. Finally, an operating regime which mitigates start/stop effects and hydrogen starvation during load changes will ensure very stable conditions at the bipolar plates’ surfaces, which strongly mitigates the risk of transpassive dissolution. As a final demonstration of the industrial feasibility of uncoated stainless-steel plates, an experimental alloy was tested under the same conditions. Results showed similar resistance to metal dissolution paired with low contact resistance at the level of C-coated or graphite plates. These results help to legitimize the efforts to industrialize uncoated stainless-steel plates since only the contact resistance challenge remains. [1] B. Pollet, S. Kocha, I. Staffell, ”Current status of automotive fuel cells for sustainable transport,” Current Opinion in Electrochemistry, vol. 16, pp. 90-95, 2019 [2] T. Novalin, B. Eriksson, S. Proch, U. Bexell, C. Moffatt, J. Westlinder, C. Lagergren, G. Lindbergh, R. Wreland Lindström, “Trace-metal contamination in proton exchange membrane fuel cells caused by laser-cutting stains on carbon-coated metallic bipolar plates,” Int. J. Hydrogen Energy, Volume 46, Issue 26, 2021 [3] T. Novalin, B. Eriksson, S. Proch, U. Bexell, C. Moffatt, J. Westlinder, C. Lagergren, G. Lindbergh, R. Wreland Lindström, “Concepts for preventing metal dissolution from stainless-steel bipolar plates in PEM fuel cells,” Energy Conversion and Management, 2022 Figure 1

The performance of anion exchange membrane fuel cells (AEMFC) has dramatically progressed in the past few years, with initial power performance matching, if not exceeding, those of proton exchange membrane fuel cells (PEMFC). The remaining challenges are i) the replacement of platinum-group-metal catalysts by catalysts based on Earth-abundant elements, ii) improved durability, and iii) the carbonatation issue when the cathode is fed with natural air. Compared to PEMFCs, the water management of AEMFC is more challenging, due to higher flux of water transported from one electrode to the other for a given current density, but also due to the high swelling of anion exchange ionomer (AEI) [1]. An optimized water management was shown to be not only critical for AEMFC power performance [2], but also for the cell stability. The chemical stability of AEM and AEI was recently shown to decrease dramatically with decreasing relative humidity [3]. During AEMFC operation, low humidity is expected on the cathode due to water consumption by the oxygen reduction reaction and due to electroosmotic drag from cathode to anode. While the water management of AEMFC is a recognized challenge, only few works have hitherto investigated it with operando techniques [4-5]. In this presentation, we will discuss the application of humidity sensors to measure on-line the relative humidity of the gas outlets of a single-cell AEMFC, allowing us to derive the water balance at each electrode (Figure 1a). The setup was applied to study the water balance and understand how it affects the AEMC power performance, focusing on one type of membrane-electrode assembly, comprising of a state-of-art anode (PtRu/C), cathode (Fe-N-C) and AEM/AEI (low density polyethylene/ethylenetetrafluoroethylene). The effect of dew point, backpressure and flow rates on cell performance and water transport were investigated. As an example of the type of results that can be obtained, Figure 1b shows the water balance at the anode and cathode as a function of time (blue and red curves, respectively), for different galvanostatic holds of 5 min each, from 0.2 to 1.2 A cm-2, at otherwise fixed conditions. As expected, the water balance is positive at the anode, and increases fairly linearly with the current density. Importantly, the water balance at the anode is always lower than the anode water balance expected if all the produced water (through the hydrogen oxidation reaction) would stay in the anode. This implies that the electroosmotic drag effect of water transport from cathode to anode is minor, and that the transport of water from anode to cathode (via back-diffusion, or other mechanism) is significant. As a result, the water balance is also positive at the cathode. Figure 1b shows also the total water balance (green curve), and that it matches with the theoretical total simply derived from the cell current density (black curve). In fact, for all operating conditions tested, the water balance was positive at the cathode, implying that the so-called cathode dry-out seldom occurs in AEMFC. The results also generally show that anode flooding is strongly connected with the maximum current density at which an AEMFC can stably operate. In conclusion, the use of humidity sensors can provide quantified insights on water dynamics in operating AEMFC, providing a tool for understanding optimized operating conditions, or for optimizing materials and components when they are designed to improve water management. References [1] J. R. Varcoe et al, Anion-exchange membrane in electrochemical energy systems, Energy & Environ. Science 7 (2014) 3135-3191 [2] N. Ul Hassan, M. Mandal, G. Huang, H. A. Firouzjaie, P. A. Kohl, W. E. Mustain, Achieving high performance and 200 h stability in anion exchange membrane fuel cells by manipulating ionomer properties and electrode optimization, Adv. Energy Materials 10 (2020) 2001986. [3] D. R. Dekel, M. Amar, S. Willdorf, M. Kosa, S. Dhara, C. E. Diesendruck, Effect of water on the stability of quaternary ammonium groups for anion exchange membrane fuel cell applications, Chem. Mater. 29 (2017) 4425-4431. [4] X. Peng et al, Using operando techniques to understand and design high performance and stable alkaline membrane fuel cells, Nature Commun. 11 (2020) 3561. [5] B. Eriksson, H. Grimler, A. Carlson, H. Ekström, R. Wreland Lindström, G. Lindbergh, C. Lagergren, Quantifying water transport in anion exchange membrane fuel cells, Int. J. Hydrogen Energy 44 (2019) 4930-4939. Acknowledgments This study was supported by the European Union’s Horizon 2020 research and innovation programme under grant agreement CREATE [721065]. We are grateful to Prof. John R. Varcoe (Univ. Surrey, UK) for providing the ionomer and membrane Figure 1

OBJECTIVE We investigate the association between the geographic proximity of the grandparents on net marital fertility and maternal survival in Sweden, 1900-1910, within the framework of the cooperative-breeding-hypothesis. METHODS Data were derived from Swedish full-count censuses (1880-1910) and the Swedish Death Index. Married couples were linked to their parental households. Poisson and logistic regression analyses were used to investigate the association between the geographical proximity of the grandparents on net marital fertility, which we measured as the number of surviving children born between 1900 and 1910, and the mother's survival. Models were fitted with and without fixed effects to assess the effects of unobserved characteristics shared at the parish and the family level. RESULTS The results indicate that net fertility and maternal survival increased with the husband's parents' geographic proximity. In contrast, we found no evidence that the geographic proximity of the wife's parents was associated with increased fertility or maternal survival. Rather, the presence of the mother's parents in the household lowered net fertility and reduced maternal survival. CONCLUSIONS This study provides evidence that kin proximity was associated with fertility and mortality of married women, and that the associations differed for paternal and maternal kin in the societal context of Swedish nuclear families (1900-1910). However, the patterns of kin proximity that we identified were correlated with characteristics such as socioeconomic status, occupation, and wealth, which also exhibited strong correlations with fertility and survival. Future research assessing the effects of kinship on demographic developments must therefore carefully consider the socio-environmental context.

The processes controlling advance and retreat of outlet glaciers in fjords draining the Greenland Ice Sheet remain poorly known, undermining assessments of their dynamics and associated sea-level rise in a warming climate. Mass loss of the Greenland Ice Sheet has increased six-fold over the last four decades, with discharge and melt from outlet glaciers comprising key components of this loss. Here we acquired oceanographic data and multibeam bathymetry in the previously uncharted Sherard Osborn Fjord in northwest Greenland where Ryder Glacier drains into the Arctic Ocean. Our data show that warmer subsurface water of Atlantic origin enters the fjord, but Ryder Glacier’s floating tongue at its present location is partly protected from the inflow by a bathymetric sill located in the innermost fjord. This reduces under-ice melting of the glacier, providing insight into Ryder Glacier’s dynamics and its vulnerability to inflow of Atlantic warmer water. A bathymetric sill in Sherard Osborn Fjord, northwest Greenland shields Ryder Glacier from melting by warm Atlantic water found at the bottom of the fjord, according to high-resolution bathymetric mapping and oceanographic data.

Heart failure (HF) management is suboptimal in Sweden despite available evidence-based guidelines. To improve HF treatment, a comprehensive HF management program (4D project) was implemented in the Stockholm County (2.1 million inhabitants).

The selectivity of CO2 electrolyzers has hitherto mainly been associated with the cathode selectivity. A few recent studies have shown that the nature of the polymer membrane can impact the system ionic selectivity, with anion exchange membranes (AEM) leading to high crossover of (bi)carbonates during operation and a CO2 pumping effect. In the present work, we investigate and compare CO2 crossover during operation through an AEM and a bipolar membrane (BPM) in a flow cell fed with gaseous CO2. With AEM, starting with 1 M KHCO3 catholyte and 1 M KOH anolyte, the anolyte pH rapidly drops from 14 to 8. This triggers an increase of 1.2 V in cell voltage at 45 mA·cm−2, due to increased OER overpotential and anolyte resistance. Steady-state operation at 45 mA·cm−2 with the AEM results in a CO2/O2 ratio of 3.6 at the anode. With BPM, the anolyte pH decreases more slowly, and the CO2/O2 ratio at the anode under steady-state at 45 mA·cm−2 is only 0.38. Overall, the cell voltage is lower with the BPM than with the AEM at steady-state. These results show the potential of BPMs to mitigate carbon crossover, which could be further reduced by optimizing their design.

Consensus is lacking in the literature about the role of socioeconomic factors on influenza-associated deaths during the 1918 pandemic. Although some scholars have found that social factors were important, others have not. In this study, we analyzed differences in excess mortality by social class in Sweden during the 1918 pandemic. We analyzed individual-level mortality of the entire population aged 30–59 years by combining information from death records with census data on occupation. Social class was measured by an occupation-based class scheme. Excess mortality during the pandemic was measured as the number of deaths relative to the number occurring in the same month the year before. Social class differences in numbers of deaths were modeled using a complementary log-log model that was adjusted for potential confounding at the family, the residential (urban/rural), and the county levels. We found notable class differences in excess mortality but no perfect class gradient. Class differences were somewhat larger for men than for women.

Fuel cells are foreseen to have an important role in sustainable energy systems, provided that catalysts with higher activity and stability are developed. In this study, highly active sputtered thin films of platinum alloyed with yttrium (Pt 3 Y) are deposited on commercial gas diffusion layers and their performance in a proton exchange membrane fuel cell is measured. After acid pretreatment, the alloy is found to have up to 2.5 times higher specific activity than pure platinum. The performance of Pt 3 Y is much higher than that of pure Pt, even if all of the alloying element was leached out from parts of the thin metal film on the porous support. This indicates that an even higher performance is expected if the structure of the Pt 3 Y catalyst or the support could be further improved. The results show that platinum alloyed with rare earth metals can be used as highly active cathode catalyst materials, and significantly reduce the amount of platinum needed, in real fuel cells.

Alloying platinum is an approach to increase the oxygen reduction reaction (ORR) activity and at the same time reduce the amount of precious platinum catalyst in proton exchange membrane fuel cells (PEMFC). In this work the cathode activity of thin films of rare earth metals (REM) alloys, Pt3Y, Pt5Gd and Pt5Tb, produced by sputter deposition onto gas diffusion layers, are evaluated in a fuel cell by means of polarization curves in O2/H2, and cyclic- and CO-stripping voltammetry in N2/5% H2. Prior to evaluation, the model electrodes were acid-treated to obtain a Pt skin covering the PtREM alloy bulk, as was revealed by energy-dispersive X-ray spectroscopy (EDX) and X-ray photoelectron spectroscopy (XPS). The core shell alloys of Pt3Y and Pt5Gd catalysts show a specific activity enhancement at 0.9 V of 2.5 times compared to pure Pt. The slightly lower enhancement factor of 2.0 for Pt5Tb is concluded to be due to leaching of the REM, that resulted in a thicker, and subsequently less strained, Pt overlayer. The high activity, combined with the minor changes in surface composition, achieved in the fuel cell environment shows that PtREM core shell catalysts are promising for the cathode reaction in PEMFC.

The performance and durability of 316L stainless steel bipolar plates (BPP) electroplated with Ni–Mo and Ni–Mo–P coatings are investigated in a proton exchange membrane fuel cell (PEMFC), using a c ...

We study the intergenerational social mobility of women by looking at how migration was associated with socioeconomic marriage mobility using complete-count census data for Sweden. The censuses 1880–1900 have been linked at the individual level, enabling us to follow almost 100,000 women from their parental home to their new marital household. Marriage market imbalances were not an important push factor for migration but we find a strong association between migration distance and marriage outcomes, both in terms of overall marriage probabilities and in terms of partner selection by SES. These results highlight the importance of migration for women's intergenerational social mobility during industrialization.

This paper proposes a novel working hydraulic system architecture for mobile machines. Load sensing, flow control and open-centre are merged into a generalized system description. The proposed system is configurable and the operator can realize the characteristics of any of the standard systems without compromising energy efficiency. This can be done non-discretely on-the-fly. One electrically controlled variable displacement pump supplies the system and conventional closed-centre spool valves are used. The pump control strategies are explained in detail. Experimental results demonstrate one solution to the flow matching problem and the static and dynamic differences between different control modes.

Membrane/ionomer degradation in proton exchange membrane (PEM) fuel cells caused by Fenton-reaction of Fe and Cu species with hydrogen peroxide is not unlike the development of Alzheimer’s in the human body. Stainless-steel dissolution under fuel cell-relevant conditions takes place via passive-transpassive-passive transitions (Figure 1) [1]. Moreover, rapid load cycling and concomitant global hydrogen starvation during the New European Driving Cycle (NEDC) [2] are very likely to create such transitions. In their presence, metal-stained carbon-coated bipolar plates lead to significant contamination of the MEA with Fe and Ni. In contrast, the mitigation of global fuel starvation in the NEDC makes it possible for the same plates to exhibit trace-metal contamination of the MEA as low as a pure graphite current collector. However, during both runs the carbon coating ensures a constant and low contact resistance between bipolar plates and gas diffusion layers (GLDs). To take the Alzheimer’s analogy a step further, these experiments show that the way the fuel cell is run can be more important than the quality of the components. In other words, lifestyle might beat genetics. At SMT we strongly believe in the power of carbon for electrochemical energy conversion due to its sustainability, low cost, high stability, high conductivity, and the absence of oxide film formation, thus, maintaining low contact resistance. We, therefore, offer (non-metal stained) carbon-precoated stainless steel for bipolar plates produced in a roll-to-roll fashion. Figure 1 . Transient dissolution behavior of a typical stainless steel, e.g., 304L, 316L, 904L, considered are only Fe and Cr species for simplification. In a potential step from OCP (+0.7 V vs. RHE), where Fe and Cr species are insoluble, to ±0 V vs. RHE, where the Fe species is soluble, Fe is preferentially leached (red trace in the transpassive part) until an all-Cr passive film has been reestablished, which takes about 100 s. The red and blue traces correspond to the Fe and Cr signal of an ICP-AES coupled to a flow cell with a stainless steel sample [1]. [1] Li X, Zhou P, Ogle K, Proch S, Paliwal M, Jansson A, et al. Transient stainless-steel dissolution and its consequences on ex-situ bipolar plate testing procedures. Int J Hydrogen Energy. 2020;45:984-95. [2] Tsotridis G, Pilenga A, De Marco G, Malkow T. EU Harmonised Test Protocols for PEMFC MEA Testing in Single Cell Configuration for Automotive Applications. Petten (The Netherlands): EU; 2015. Figure 1

AMPK activated protein kinase (AMPK), a master regulator of energy homeostasis, is activated in response to an energy shortage imposed by physical activity and caloric restriction. We here report on the identification of PAN-AMPK activator O304, which - in diet-induced obese mice - increased glucose uptake in skeletal muscle, reduced β cell stress, and promoted β cell rest. Accordingly, O304 reduced fasting plasma glucose levels and homeostasis model assessment of insulin resistance (HOMA-IR) in a proof-of-concept phase IIa clinical trial in type 2 diabetes (T2D) patients on Metformin. T2D is associated with devastating micro- and macrovascular complications, and O304 improved peripheral microvascular perfusion and reduced blood pressure both in animals and T2D patients. Moreover, like exercise, O304 activated AMPK in the heart, increased cardiac glucose uptake, reduced cardiac glycogen levels, and improved left ventricular stroke volume in mice, but it did not increase heart weight in mice or rats. Thus, O304 exhibits a great potential as a novel drug to treat T2D and associated cardiovascular complications.

Objective: The aim of this study is to describe patients with heart failure and an ejection fraction (EF) of more than or equal to 40%, managed in both Primary- and Hospital based outpatient clinics separately with their prognosis, comorbidities and risk factors. Further to compare the heart failure medication in the two groups. Design: We used the prospective Swedish Heart Failure Registry to include 9654 out-patients who had HF and EF ≥40%, 1802 patients were registered in primary care and 7852 in hospital care. Descriptive statistical tests were used to analyze base line characteristics in the two groups and multivariate logistic regression analysis to assess mortality rate in the groups separately. Setting: The prospective Swedish Heart Failure Registry. Subjects: Patients with heart failure and an ejection fraction (EF) of more than or equal to 40%. Main outcome measures: Comorbidities, risk factors and mortality. Results: Mean-age was 77.5 (primary care) and 70.3 years (hospital care) p

Fuel cells are foreseen to have an important role in sustainable energy systems, provided that catalysts with higher activity and stability are developed. In this study, highly active sputtered thin films of platinum alloyed with yttrium (Pt

Why do certain firms prosper and grow old while other firms fail? Established knowledge tells us that longevity is related to the firm's ability to adapt to market conditions, through product diversification, learning-by-doing and adopting new strategies regarding technology, human resources and management. By estimating duration models using new data covering the entire Swedish tobacco industry, we find that firms employing more women were considerably less likely to fail than other firms. Industry feminisation may be seen as the outcome of a competitive process where more feminised firms as a result of their extended longevity came to dominate the industry.

Women have typically been paid less than men throughout history. We investigate earnings in Swedish cigar making around 1900. Strength was unimportant, yet the gender wage gap was large. Differences in characteristics, such as age and experience, and different jobs within firms, account for two-thirds of the gap overall, and the entire gap for piece-rate workers. Firms were as willing to employ women as men in the better-paying piece-rate section, and women were willing to take those jobs. In contrast, discrimination was extensive in the time-rate section. Men in this section benefited from greater outside opportunities and customary wages elsewhere. Theory holds that labour market discrimination will reduce profitability, and make firm survival harder, a proposition that has never been tested historically. We find that cigar firms that feminized their workforces most extensively were most likely to survive. Product market competition prevented firms employing (overpaid) men to any great extent. We argue that economic historians must interpret industry-specific gender wage differentials in the context of workers' outside opportunities, and in the context of product markets, which can—and in this case did—limit firms' room for manoeuvre.

Gonorrhoea incidence has increased substantially in Stockholm during the past years. These increases have coincided with changes in testing practice from solely culture-based to nucleic acid amplification tests (NAAT). Gonorrhoea NAAT is integrated with Chlamydia trachomatis testing and due to opportunistic screening for chlamydia, testing prevalence for gonorrhoea has increased substantially in the Stockholm population. The aim of this study was to examine epidemiological risk-factors for discordant case which are NAAT positive but culture negative. These discordant cases are especially problematic as they give rise to diagnostic and treatment uncertainties with risk for subsequent sequelae. All gonorrhoea cases from Stockholm county during 2011-2012 with at least one positive N. gonorrhoea NAAT test and follow-up cultures were included (N = 874). Data were analysed using multivariate and stratified logistic regression models. Results showed that women were 4-times more likely (OR 4.9; 95% CI 2.4-6.7) than men to have discordant cultures. Individuals tested for gonorrhoea without symptoms were 2.3 times more likely (95% CI 1.5-3.5) than those with symptoms to be discordant. NAAT method and having one week or more between NAAT and culture testing were also indicative of an increased likelihood for discordance. Using NAAT should be based on proper clinical or epidemiological indications and, when positive, followed-up with a culture-based test within one week if possible. Routine gonorrhoea testing is not recommended in low prevalence populations.

The hypothesis of a km-thick ice shelf covering the entire Arctic Ocean during peak glacial conditions was proposed nearly half a century ago. Floating ice shelves preserve few direct traces after their disappearance, making reconstructions difficult. Seafloor imprints of ice shelves should, however, exist where ice grounded along their flow paths. Here we present new evidence of ice-shelf groundings on bathymetric highs in the central Arctic Ocean, resurrecting the concept of an ice shelf extending over the entire central Arctic Ocean during at least one previous ice age. New and previously mapped glacial landforms together reveal flow of a spatially coherent, in some regions >1-km thick, central Arctic Ocean ice shelf dated to marine isotope stage 6 (∼140 ka). Bathymetric highs were likely critical in the ice-shelf development by acting as pinning points where stabilizing ice rises formed, thereby providing sufficient back stress to allow ice shelf thickening., The development of pan-Arctic Ocean ice shelves during peak glacials was proposed in the 1970s, an idea that has been disputed due to lack of evidence. Here, the authors present geophysical mapping data supporting the presence of such an ice shelf during the peak of the penultimate glaciation ∼140–160 ka.

Pine Island Glacier drains portions of the West Antarctic Ice Sheet into the Amundsen Sea. During the Last Glacial Maximum the glacier extended nearly 500 km from its present location onto the outer continental shelf. Unusually restricted sea-ice cover during the austral summer of 2010 allowed for a systematic multibeam swath-bathymetric and chirp sonar survey of the mid-shelf section of Pine Island Trough. The mapped glacial landforms reveal new information about the paleo-Pine Island Ice Stream's dynamic retreat from the mid-shelf area and confirm previous suggestion of a retreat in distinct steps. The periods of grounding line stability during the overall retreat phase are marked by sediment accumulations, i.e. grounding zone wedges. These wedges are here mapped in sufficient detail to characterize spatial dimensions and estimate the volume of deposited sediment. Considering a range of sediment flux rates from the paleo-Pine Island Ice Stream we estimate that the largest and most clearly defined grounding zone wedge, located at about 73°S in the surveyed area, took between 600 and 2000 years to form. The ice stream retreated landward of this wedge before 12.3 cal ka BP. The swath-bathymetric imagery of landforms in Pine Island Trough includes glacial features that suggest that retreat between periods of grounding line stability may be associated with episodes of ice shelf break-up. The depths of grounding line wedges decrease in a landward direction, from 740 to 670 m, and record elevation of the grounding line as it stepped landward. In all, the grounding line elevation varied by only ∼80 m over a distance of just over 100 km, implying a low ice sheet profile during retreat. Finally, we revisited seismic reflection profile NB9902, acquired along Pine Island Trough in 1999, in combination with the newly acquired swath-bathymetric imagery from 2010. Together these data show that the ice stream paused during its retreat to form grounding zone wedges at an area in central Pine Island Trough where a high in dipping bedrock strata exists and the glacial trough is narrow, forming a bathymetric “bottle neck”.

The catastrophic break-ups of the floating Larsen A and B ice shelves (Antarctica) in 1995 and 2002 and associated acceleration of glaciers that flowed into these ice shelves were among the most dramatic glaciological events observed in historical time. This raises a question about the larger West Antarctic ice shelves. Do these shelves, with their much greater glacial discharge, have a history of collapse? Here we describe features from the seafloor in Pine Island Bay, West Antarctica, which we interpret as having been formed during a massive ice shelf break-up and associated grounding line retreat. This evidence exists in the form of seafloor landforms that we argue were produced daily as a consequence of tidally influenced motion of mega-icebergs maintained upright in an iceberg armada produced from the disintegrating ice shelf and retreating grounding line. The break-up occurred prior to ca. 12 ka and was likely a response to rapid sea-level rise or ocean warming at that time.

A review of recent and current research on individual metering fluid power systems is presented. An overview of different systems and their pros and cons is given. General challenges related to independent metering fluid power systems are discussed. The major choices in the design of these systems are the hardware layout and the control strategy. The evolution of existing independent metering fluid power systems from the 1970s until the present day is also presented.