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In this study we investigate the Na insertion process occurring in the "free carbon" phase embedded in two different SiCN(O) matrices with operando Raman spectroscopy. The two SiCN(O) samples have been prepared using two different thermal treatments carried out at 1000 °C (SiCN(O)1000) and 1400 °C (SiCN(O)1400). X‐ray diffraction as well as argon adsorption reveal significant structural and morphological differences between the materials. SiCN(O)1000 shows an amorphous nature whereas SiCN(O)1400 reveals the presence of crystalline β‐SiC, accompanied by a notable increase in surface area (from 56.7 m2/g to 331 m2/g) and micropore volume (from 0.02 cm3/g to 0.12 cm3/g). These alterations in the ceramic matrix due to thermal treatment affect significantly the electrochemical performance with initial de‐sodiation capacities of 112.4 mAh/g and 52.3 mAh/g for SiCN(O)1000 and SiCN(O)1400, respectively. Operando Raman spectroscopy, carried out during the sodiation and de‐sodiation of the SiCN(O) ceramics, reveals the microstructural changes occurring to the "free carbon" phase during the storage of sodium ions. As sodium is inserted, a shift in the G‐band position is observed in both the samples from about 1600 cm−1 to 1555 cm−1, with a concomitant decrease of the D‐band intensity and the distance between defects (LD) growing from 7.5 nm to 17.5 nm. Upon de‐sodiation, SiCN(O)1400 exhibits an inferior storage reversibility compared to SiCN(O)1000. This may be attributed to the irreversible sodium trapping occurring in SiCN(O)1400, highlighted by the reduced efficiency of the electrochemical process. [ABSTRACT FROM AUTHOR]

A facile and eco‐friendly strategy is presented for synthesizing novel nanocomposites, with MoP quantum dots (QDs) as cores and graphitic carbon as shells, these nanoparticles are dispersed in a nitrogen and phosphorus‐doped porous carbon and carbon nanotubes (CNTs) substrates (MoP@NPC/CNT). The synthesis involves self‐assembling reactions to form single‐source precursors (SSPs), followed by pyrolysis at 900 °C in an inert atmosphere to obtain MoP@NPC/CNT‐900. The presence of carbon layers on the MoP QDs effectively prevents particle aggregation, enhancing the utilization of active MoP species. The optimized sample, MoP@NPC/CNT‐900, exhibits remarkable electrocatalytic activity and durability for the hydrogen evolution reaction (HER). It demonstrates a low overpotential of 155 mV at 10 mA cm−2, a small Tafel slope of 76 mV dec−1, and sustained performance over 20 hours in 0.5 M H2SO4. Furthermore, the catalyst shows excellent activity in 1 M KOH, with a relatively low overpotential of 131 mV and long‐term durability under constant current input. The exceptional HER activity can be attributed to several factors: the superior performance of MoP QDs, the large surface area and good conductivity of the carbon substrates, and the synergistic effect between MoP and carbon species. [ABSTRACT FROM AUTHOR]

Water‐splitting processes require advanced catalysts for the electrocatalytic hydrogen evolution reaction (HER) and oxygen evolution reaction (OER). A facile and cost‐effective approach using single‐source precursors (SSPs) to prepare active and durable bifunctional electrocatalysts consisting of core–shell structured transition metal phosphide (TMPs) nanoparticles dispersed and immobilized in a highly defective N‐, P‐codoped carbon matrix. The bimetallic FeNi phosphide supported on N‐, P‐codoped carbon is synthesized through pyrolysis at 900 °C under an argon atmosphere (FeNiP@NPC‐900), displaying promising electrocatalytic performance for both HER and OER, with low overpotentials of 191 and 278 mV, respectively. Furthermore, FeNiP@NPC‐900 exhibits remarkable durability in both acidic and alkaline electrolytes. The excellent catalytic and long‐term performance is attributed to several factors, including the novel SSP approach, which prevents the agglomeration of active TMPs particles, the in situ formation of exposed nanopores during the carbonization of the precursor without using surfactants, and the heterostructure between highly defective carbon and TMPs, which positively influences the electronic structure at the interface and facilitates charge transfer. The unique core–shell nanostructure protects the catalytically active phase from corrosion and synergistically promotes the activity performance. Therefore, a new strategy for designing active and stable heterostructured TMPs@carbon‐based electrocatalysts is provided. [ABSTRACT FROM AUTHOR]

Technical interactions (multiple fleets fishing multiple species with various gears, as either target or bycatch), bycatch regulations through a landing obligation, and biological and economic effects of climate change, affecting fisheries yield and profits, provide a challenge for demersal mixed fisheries of the North Sea. A multi‐stock, multi‐fleet, bioeconomic model was used to understand management options under these combined influences. Scenarios considered climate change effects on recruitment of three main gadoid stocks (cod – Gadus morhua, saithe – Pollachius virens, whiting – Merlangius merlangus), possible future developments of fuel and fish prices, and strict implementation of a landing obligation. The latter leads to decreased yield and profits in the short term due to increased choke effects, mainly of North Sea cod, being influenced by climate‐induced productivity changes. Allowing fishing above FMSY, but within sustainable limits, or limiting year‐to‐year quota changes, could help buffer initial losses at the expense of decreased profits in the mid‐ to long‐term. Economic performance of individual fleets was linked to their main target's stock status, cost structure, and fuel and fish prices. The results highlight a need to consider both biological and economic consequences of climate change in the management of mixed fisheries. [ABSTRACT FROM AUTHOR]

Ocean biogeochemical provinces have historically been used to characterize regions of similar biogeography, allowing for large‐scale comparisons and the definition of possible management units. Recent studies have shown that ocean color (OC) may be used as a proxy for a range of physical and biological parameters, allowing for a more direct approach in defining and monitoring provinces. The current work investigates whether OC‐derived provinces (area of a given OC type) can be identified in the North Sea and if they can provide insight into the system's dynamics. The analysis workflow was organized into three main steps: 1. OC type classification based on clustering of normalized reflectance spectra, 2. OC type characterization following match‐ups to other biological and physical covariates, and 3. Exploration of drivers of OC province dynamics. Based on data from 1997–2019, four main OC types were identified, which are shown to be related to bio‐optical, physical, and zooplankton community covariates. Atlantic‐associated OC types varied in their coverage of the North Sea on seasonal and interannual scales, with increased penetration related to periods of a weakened circulation. Interannual variability of OC province extent was also found to correlate with an index of the Subpolar Gyre. These results indicate that the dynamics of OC provinces in the North Sea are likely driven by the interaction between large‐scale circulation and local wind‐driven and baroclinic currents. The perspective offered by OC provinces helps elucidate spatiotemporal patterns of plankton and is proposed as a novel operational index for additional exploration of ecosystem functioning. Plain Language Summary: A water's color, from muddy brown to green or clear blue, reflects a range of information regarding its origin and characteristics. For example, we may be able to infer the amount of sediments or the concentration and composition of its algal community (phytoplankton), which form the base of the food web for many marine ecosystems. Using color measurements obtained from historical satellite imagery (1997–2019), North Sea water types were defined, which related to a range of parameters; including salinity, phytoplankton concentration, and associated zooplankton community. Of particular interest are the clearer, bluish water types associated with Atlantic waters that enter the North Sea around the area of the Shetland Islands, whose inflow variability is thought to be an important driver of the North Sea ecosystem over time. The results show that the coverage of Atlantic waters changes over seasonal and long‐term time scales, which are related to the strength of currents and changes in the source waters arriving to the European shelf. In addition to providing insight to historical changes, the method's use of freely available satellite imagery makes it an attractive approach for future monitoring of the ecosystem. Key Points: Four ocean color types are defined for the North Sea, which are associated with bio‐optical, physical, and zooplankton community covariatesOcean color province dynamics relate to variability in local wind‐forced currents and large‐scale variations in source watersAtlantic‐associated ocean color types show highest coverage in the North Sea during periods of reduced wind‐forced circulation [ABSTRACT FROM AUTHOR]

Despite regular reforms, problems under the EU's Common Fisheries Policy (CFP) persist. In order to identify priorities for future reforms of the policy, we developed an analytical framework consisting of 17 criteria and specifying indicators, derived from scientific, wider fisheries, and common resources literature. We applied the framework to the CFP governance system, its regulations, institutions, and processes at EU as well as member state level. The results show that the CFP does not fully meet any of the 17 criteria for an effective resource policy. Its performance was assessed as "neutral" regarding 10 criteria and "negative" regarding seven criteria. Trend analysis shows that there is a slightly positive trend regarding the CFP's performance, with five criteria trending positively, 11 showing a neutral trend and only one criterion trending negatively (simplicity of rules). The analysis identified five criteria which are performing badly and have not improved over time: simplicity of rules, user‐pays principle, resource efficiency, accountability, and compliance mechanisms. Future reforms of the CFP should first and foremost address these criteria while continuing efforts to improve the CFP's performance regarding other criteria. The evaluation of the CFP demonstrates the applicability of the analytical framework which can also be applied to other multilevel fisheries governance systems. Moreover, the results can inform reforms of Regional Fisheries Management Organisations. Like the CFP, these institutions manage transboundary fisheries and have not effectively addressed the issues of resource rent capture and resource efficiency. [ABSTRACT FROM AUTHOR]

This experimental study investigates the impact of affective attitudes on risk and return estimates of stocks. Participants rate well-known blue-chip firms on an affective scale and forecast risk and return of the firms' stock. We find that positive affective attitudes lead to a prediction of high return and low risk, while negative attitudes lead to a prediction of low return and high risk. This bias increases with participants' confidence in their ratings and decreases with financial literacy. Firm characteristics such as a firm's marketing expenditures and the strength of its brand have a positive impact on its affective rating. [ABSTRACT FROM AUTHOR]

The understanding of spatio-temporal dynamics of marine ecosystems is crucial for ecosystem-based fisheries management and climate change impact assessments. We quantified temporal changes in the distribution of 0-group cod ( Gadus morhua) and grey gurnard ( Eutriglia gurnardus), a primary predator of 0-group cod, with the help of regression kriging and assessed the temporal dynamics of the related spatial predator-prey overlap of these two species at different spatial scales. We analysed the robustness of relationships among abiotic habitat properties (temperature, salinity and depth) and abundance. Small cod was mainly found in low salinity areas of the Skagerrak but larger year classes were able to expand their distribution area towards the central and northern North Sea. In contrast, grey gurnard was mainly found in waters with salinities above 33 and temperatures above 14°C. This species has expanded its high density areas in the central North Sea northward over the last two decades. Recruitment success of cod was negatively correlated to a Moran's I cross-correlation index, a proxy for the degree of spatial overlap between both species. Strong cod year classes overlapped less with grey gurnard at the large and medium spatial scale. In general, the relationships between abiotic habitat properties and abundance showed an increased inter-annual variability, which was likely caused by underlying factors not taken into account in the distribution models. Thus assemblage modeling approaches combining the strength of different model types should be considered in the future to predict potential distribution patterns under climate change scenarios. [ABSTRACT FROM AUTHOR]

This paper conducts a comprehensive asset pricing study based on a unique dataset for the German stock market. For the period 1963 to 2006 we show that value characteristics and momentum explain the cross-section of stock returns. Corresponding factor portfolios have significant premiums across various double-sorted characteristic-based test assets. In a horse race of competing asset pricing models, the Fama-French 3-factor model does a poor job in explaining average stock returns. The Carhart 4-factor model performs much better, but a 4-factor model containing an earnings-to-price factor instead of a size factor does even slightly better. [ABSTRACT FROM AUTHOR]

Technical trading strategies assume that past price trends predict future ones. Their application may be profitable if the past trend reflects fundamental information that has not yet been fully priced. However, if the trend merely reflects temporary pricing pressures, technical trading will presumably fail. We argue that using financial statements as an additional source of information helps to avoid such failure. We implement a trading strategy that uses operating cash flows to identify enduring past price upturns. This strategy outperforms a purely technical momentum strategy, seems to be practicable, and its profits exceed transactions costs. [ABSTRACT FROM AUTHOR]

We test the frequently made claim that SRI funds are conventional funds in disguise. For this purpose, we compare the portfolio holdings of SRI funds to conventional funds with respect to their social and environmental standards. Our empirical study of US equity funds shows that SRI funds have a significantly higher ethical ranking than standard funds, i.e., they are not conventional funds in disguise. This result holds for all ethical criteria we investigate. It is stable over time and holds after controlling for several fund characteristics. Finally, we find no evidence that our result is generated by window dressing strategies of SRI funds. [ABSTRACT FROM AUTHOR]

Previous market microstructure research focuses on commonality in liquidity at the inside spread. However, liquidity at the inside spread only determines the systematic liquidity risk of small and medium trades. We study commonality in displayed liquidity beyond best prices, which determines the systematic liquidity risk of large trades. We show that it is much larger than commonality at the inside spread. The deeper we look into the order book, the higher is the level of commonality. In addition, it rises in the morning and when markets fall. [ABSTRACT FROM AUTHOR]

This paper examines the influence of the position of a fund within its family on its subsequent net-inflows. Our empirical study of the US equity mutual fund market shows that reaching a top position within the family leads to large inflows. These inflows accrue beyond those expected, given the performance of the fund in its respective market segment. The effect is much stronger in large families than in small families. We also find that inflows significantly increase if a fund moves into the top positions within its family from one year to another. These results lead to competition within the fund family and to important risk taking incentives for fund managers. [ABSTRACT FROM AUTHOR]

More and more investors apply socially responsible screens when building their stock portfolios. This raises the question whether these investors can increase their performance by incorporating such screens into their investment process. To answer this question we implement a simple trading strategy based on socially responsible ratings from the KLD Research & Analytics: Buy stocks with high socially responsible ratings and sell stocks with low socially responsible ratings. We find that this strategy leads to high abnormal returns of up to 8.7% per year. The maximum abnormal returns are reached when investors employ the best-in-class screening approach, use a combination of several socially responsible screens at the same time, and restrict themselves to stocks with extreme socially responsible ratings. The abnormal returns remain significant even after taking into account reasonable transaction costs. [ABSTRACT FROM AUTHOR]

Highlights the impact of short selling restrictions and early unwinding opportunities on the relation between futures and spot prices. Analysis of the influence of optimal arbitrage trading on the mispricing; Influential factors for the mispricing behavior.

Discusses a study on the price relation between the German stock performance index, DAX, and DAX futures. No dividend risk; Relationship cannot be described by the cost-of-carry model; Undervaluation of futures contracts with time to maturity; Lower risk as contract nears maturity.

The first part of the thesis deals with the equilibrium mispricing between spot and futures markets and the impact of arbitrage trading on the price relation. The numerical solution of the model providers the following main results. First, the mean reversion of the mispricing is arbitrage induced. Secondly, arbitrage trading and mean reversion of the mispricing depend on the behavior of the mispricing in the past. Third, the impact of arbitrage trading on the mispricing increases with a decreasing time to maturity of the futures contact. Finally, arbitrage trading keeps the mispricing away from zero in certain cases. This suggests that mispricing may not exist despite arbitrage trading but due to arbitrage trading. These hypotheses are tested using and intraday data from the German stock index DAX and DAX futures. Empirical results concerning the level, the mean reversion and the path dependence of the mispricing are provided. They strongly support the view that the early unwind option has a major impact on the spot-futures price relation. The second main part of the thesis deals with the value of the early unwind option in equilibrium. Contrary to standard option pricing theory, the underlying of this option, the mispricing, is modelled as an endogenous variable that is determined in equilibrium. Therefore, the early unwind option not only depends on its underlying but also the underlying of the option also depends on the option itself. The option valuation is done by calculating the expected profits of an optimal dynamic arbitrage with and without early unwinding opportunities. Several features of the option value are found that are not consistent with traditional option pricing models. First, the option value increases with the number of open arbitrage position held by the arbitrageur, but at a decreasing rate. Secondly, the impact of changes in the volatility on the option value differs for in- and out-of-the-money options. Finally, the option value is... [ABSTRACT FROM AUTHOR]