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• We examine gender stereotypes (GS) of students, parents, teachers, and classmates. • Students' GS are related to motivational and affective outcomes in math. • Parents' GS are related to girls' but not boys' math interest and anxiety. • Students seem more susceptible to gender stereotypes of classmates than teachers. • Teacher stereotypes are not related to student self-concept, interest, or anxiety. We examined associations between the explicit mathematics-related gender stereotypes of students, parents, teachers, and classmates and students' motivational-affective outcomes in mathematics (self-concept, interest, anxiety) at the end of Grade 9. Based on representative data from the German Trends in Student Achievement 2018 study (N = 30,019), results of latent multilevel mixture models show that boys' and girls' explicit beliefs in the stereotype favoring their own gender in-group (i.e., boys'/girls' belief that boys/girls do better at mathematics) were related to higher levels of self-concept and interest and to lower anxiety. Parents' gender stereotypes showed an incremental association with all three outcomes for girls but only with mathematics self-concept for boys. Gender stereotypes of teachers were not related to students' outcomes. However, classmates' stereotypes favoring girls or boys in mathematics were negatively associated with outcomes of the positively stereotyped group. Thus, a male student in a classroom with classmates who share the traditional stereotype that boys do better at mathematics than girls would hold a lower self-concept and interest and higher anxiety level after controlling for the beneficial individual association of himself having the same belief and his motivational and affective outcomes. Similarly, a girl's motivational-affective outcomes would be more favorable in the same environment characterized by the shared traditional stereotype of mathematics as a male domain after controlling for the negative individual association. Shared stereotypes in the classroom could thus trigger social comparison processes to which students are more susceptible than to stereotypes of their teachers. [ABSTRACT FROM AUTHOR]

Disadvantages for girls in mathematics and science as well as the general educational disadvantages faced by students with an immigrant background are two widely discussed equity issues. However, previous research has rarely addressed both issues simultaneously. On the basis of theoretical considerations suggesting possible interaction effects, we compared patterns of gender difference in mathematics and science achievement and motivation of students with and without an immigrant background. The results show negligible gender differences in achievement measures, providing further support for the gender similarities hypothesis. With regard to motivational student characteristics, we found significant advantages for male students in all tested domains except biology. This effect pattern was found for students with and without an immigrant background. Immigrant students, especially those with a Turkish background, lagged behind their native German peers in achievement (but not motivation), yet no clear-cut interaction effects with gender were found. We conclude that the gender gap in STEM domains still exists with regard to motivation despite the lack of significant differences in achievement. Female students with an immigrant background seem to have neither a double disadvantage nor a relative advantage. Yet there was some evidence that men with a Turkish background may be disadvantaged in science achievement. [ABSTRACT FROM AUTHOR]

The Earth's extratropical troposphere is equilibrated by turbulent eddy fluxes of potential temperature and momentum. The equilibrated state has the remarkable characteristic that isentropic slopes leaving the surface in the subtropics reach the tropopause near the Poles. It has been speculated that turbulent eddy fluxes maintain this state for a wide range of radiative forcing and planetary parameters. In a previous study, the authors showed that this state needs to be associated with an eddy diffusivity of Ertel potential vorticity that is largest at the surface and decays through the troposphere to approximately zero at the tropopause. This result is confirmed in this study using atmospheric reanalysis and idealized numerical simulations. However, it is also shown that the vertical profile of the eddy diffusivity can change, resulting in different isentropic slopes and climates. This is illustrated with a series of idealized numerical simulations with varying planetary scales and rotation rates. [ABSTRACT FROM AUTHOR]

The Matthew effect hypothesis of academic development predicts that students with higher initial achievement will develop further skills at a faster rate resulting in cumulative advantages. Prior research has focused on the development of reading competence in primary school. To extend this research, we used a sample of N = 1,010 German students in Grades 5 to 9 to compare the development of reading and mathematics skills between high-achieving high-track secondary school students and their peers to clarify whether rates of academic development differ between these groups. Using latent growth curve modeling, we found a pattern of compensation in both domains—that is, the achievement gap became smaller and this was the case particularly in the early grades of secondary school. Thus, our results provide no evidence for the existence of Matthew effects in reading and mathematics in lower secondary school. • We examined the achievement trajectories of high achievers and other students. • We focused on reading and mathematics development in high-track secondary school. • We found no evidence of Matthew effects in reading or mathematics. • Rather, a compensation process seemed to occur. [ABSTRACT FROM AUTHOR]

In recent studies, the existence and relevance of achievement composition effects on students' individual achievement have been called into question because of the methodological challenges arising in multilevel analyses. Our study examined how class-average achievement is related to students' achievement development across one school year. We used data from Germany, which has a secondary school system with large achievement differences between schools and classrooms due to rigid, explicit between-school tracking practices. We accounted for two methodological challenges, controlling for both selection bias and measurement error. Adopting an approach based on integrative data analysis (IDA), we systematically (re)analyzed five German longitudinal large-scale data sets. This IDA approach allowed us to quantify the extent to which results vary across (a) different longitudinal data sets and (b) different analytical strategies (i.e., ways of accounting for confounding variables and measurement reliability). Overall, we found both general achievement composition effects and narrower peer spillover effects (i.e., effects of student composition above and beyond the effects of tracking) in the German setting, even after controlling for measurement error and selection bias. Our results counter recent suggestions that composition effects on achievement development may be mere phantom effects due to methodological misspecifications. However, estimates of composition effects varied substantially based on the analytical approach. We conclude with considerations regarding how to interpret composition effects in multilevel modeling and which effects are of interest for educational research. Educational Impact and Implications Statement: The study investigates whether students experience better achievement development when they have high-achieving classmates, an effect that is known as the achievement composition effect. This question has been controversial in the literature, and several researchers who used a new analytical strategy to analyze compositional effects have recently suggested that achievement composition effects may be mere "phantom effects," meaning that being in a classroom with higher-achieving peers may not have any beneficial effect on students' achievement development or may even have detrimental effects on it. We (re)analyzed five longitudinal studies from Germany, which allowed us to examine the extent to which results varied across studies using different longitudinal data sets and different analytical strategies. Overall, we found positive achievement composition effects. However, they differed based on the analytical strategies used and how they operationalized the effect. The results support the argument that being surrounded by higher-achieving peers can be beneficial for students' learning gains and, at the same time, being surrounded by lower-achieving peers may negatively affect students' learning gains. [ABSTRACT FROM AUTHOR]

Some German states recently reformed their tracking practices by reducing the number of secondary school track options from up to four to a two-path structure, in which students can continue their school career until they acquire the general university entrance qualification in both tracks (academic and comprehensive). We examine whether these de-tracking reforms were, as intended, associated with a change in students' educational aspirations and whether they reduced socioeconomic disparities in students' educational aspirations. We analyze representative data of around 65,000 ninth graders from states with and without reforms from pre- and post-reform periods (2012 to 2018), using a Difference-in-Differences approach and a regression of students' educational aspirations on their socioeconomic backgrounds. Our results suggest that students' educational aspirations have increased in the wake of the de-tracking reforms, but that socioeconomic disparities in students' educational aspirations have increased rather than weakened. Implications for tracking practices and socioeconomic disparities are discussed. • De-tracking reforms were recently introduced in some German federal states. • Representative data (ca. 65,000 9th graders) from states with and without de-tracking reforms before and after the reforms. • Difference-in-Differences analyses showed increase in students' educational aspirations following the de-tracking reforms. • Socioeconomic disparities in students' educational aspirations have increased rather than weakened. [ABSTRACT FROM AUTHOR]

A wind turbine's power curve relates its power production to the wind speed it experiences. The typical shape of a power curve is well known and has been studied extensively. However, power curves of individual turbine models can vary widely from one another. This is due to both the technical features of the turbine (power density, cut-in and cut-out speeds, limits on rotational speed and aerodynamic efficiency), and environmental factors (turbulence intensity, air density, wind shear and wind veer). Data on individual power curves are often proprietary and only available through commercial databases. We therefore develop an open-source model for pitch regulated horizontal axis wind turbine which can generate the power curve of any turbine, adapted to the specific conditions of any site. This can employ one of six parametric models advanced in the literature, and accounts for the eleven variables mentioned above. The model is described, the impact of each technical and environmental feature is examined, and it is then validated against the manufacturer power curves of 91 turbine models. Versions of the model are made available in MATLAB, R and Python code for the community. • A generic power curve model dependent on main turbine characteristics is proposed. • Main environmental parameters are considered. • A statistical analysis of the model inputs is proposed. • The modelled output is validated against numerous manufacturer power curves. • Versions of the model are made available in MATLAB, R and Python. [ABSTRACT FROM AUTHOR]

Self-concept in mathematics (MSC) and interest in mathematics are important predictors of whether a student will choose to major in a science, technology, engineering, or mathematics (STEM) field at university. Research on the big-fish-little-pond effect (BFLPE) has shown that both predictors are affected by the achievement composition of students in schools. That is, given the same individual ability, students in higher achieving schools exhibit lower MSC and interest in mathematics than students in lower achieving schools due to social comparison processes. The BFLPE has been replicated in high school settings many times, but less is known about the long-term effects of this context effect. In the present study, we investigated the long-term effects of the BFLPE on the aspiration to major in and the actual decision to major in a STEM field at university. We used data from a German longitudinal study. The results showed no direct BFLPE on the aspiration to enroll in a STEM major at the end of high school or on actual enrollment in a STEM major 2 years after graduating from high school. However, small negative indirect effects of the BFLPE via MSC and interest in mathematics on the aspiration to and enrollment in a STEM major occurred. In sum, the longitudinal BFLPE on STEM major choice was small. Educational Impact and Implications Statement: In the present study, we used a German longitudinal dataset to investigate the long-term effects of schools' achievement-related student composition (big-fish-little-pond effect) on (a) the aspiration to major in and (b) the actual decision to major in a science, technology, engineering, and mathematics (STEM) field at university. Given the same individual achievement level, students in higher performing schools exhibited a lower self-concept and interest in mathematics (which then affected subsequent major choice). Social comparison processes can explain these results, as students evaluate their ability level by comparing themselves to their peers. The long-term effect of these social comparisons on enrollment in a STEM major at university was statistically significant but small. Furthermore, the results indicated that students compare their own individual achievement in the verbal and mathematics domains (dimensional comparisons) when choosing whether to major in a STEM field than compare themselves socially with their peers. Considering our results, educators should be aware of and potentially discuss such comparison processes when counseling students who are preparing to select their major at university. [ABSTRACT FROM AUTHOR]

Highlights • A new ability grouping takes place during the transition to upper secondary school. • Significant BFLPEs occurred in cross-sectional analyses before and after transition. • In upper secondary school, contrast- and assimilation effects occurred simultaneously. • The BFLPE from lower secondary school did not persist into upper secondary school. • Students used a current and local frame of reference to engage in social comparisons. Abstract Research on the big-fish-little-pond effect (BFLPE) has shown that the learning environment is important for the development of academic self-concept (ASC) because students use social comparisons to evaluate their ability level. Whereas cross-sectional studies have often replicated the BFLPE, less is known about this effect from a longitudinal perspective during times when changes occur in students' learning environments. Thus, we focused on a timespan during which a student's learning environment changes—the transition from lower to upper secondary school. In upper secondary school in Germany, students leave their former classes and take either advanced or basic courses. Advanced courses are characterized by more demanding curricula and a higher achieving student body. Consequently, the compositions of the student groups change. We examined the BFLPE in the context of math self-concept (MSC) in N = 1330 students during the transition from lower secondary (10th grade) to upper secondary school (12th grade) in Germany using longitudinal, large-scale data. We focused on contrast and assimilation effects as well as on the longitudinal persistence of the BFLPE from lower to upper secondary school. The BFLPE occurred at both measurement points, and there was an assimilation effect of the enrollment in advanced courses in 12th grade. The BFLPE from 10th grade did not persist into 12th grade, indicating that the BFLPE does not persist through contextual changes. Instead, information about the current frame of reference (i.e., average course achievement and course level) seems to overwrite context effects from previous learning environments, even if this change occurs within schools as constant macro-contexts. [ABSTRACT FROM AUTHOR]

There are two distinct parameterizations for the restratification effect of mesoscale eddies: the Greatbatch and Lamb (1990, GL90, https://journals.ametsoc.org/view/journals/phoc/20/10/1520-0485%5f1990%5f020%5f1634%5fopvmom%5f2%5f0%5fco%5f2.xml?tab%5fbody=abstract-display) parameterization, which mixes horizontal momentum in the vertical, and the Gent and McWilliams (1990, GM90, https://journals.ametsoc.org/view/journals/phoc/20/1/1520-0485%5f1990%5f020%5f0150%5fimiocm%5f2%5f0%5fco%5f2.xml) parameterization, which flattens isopycnals adiabatically. Even though these two parameterizations are effectively equivalent under the assumption of quasi‐geostrophy, GL90 has been used much less than GM90, and exclusively in z‐coordinate models. In this paper, we compare the GL90 and GM90 parameterizations in an idealized isopycnal coordinate model, both from a theoretical and practical perspective. From a theoretical perspective, GL90 is more attractive than GM90 for isopycnal coordinate models because GL90 provides an interpretation that is fully consistent with thickness‐weighted isopycnal averaging, while GM90 cannot be entirely reconciled with any fully isopycnal averaging framework. From a practical perspective, the GL90 and GM90 parameterizations lead to extremely similar energy levels, flow and vertical structure, even though their energetic pathways are very different. The striking resemblance between the GL90 and GM90 simulations persists from non‐eddying through eddy‐permitting resolution. We conclude that GL90 is a promising alternative to GM90 for isopycnal coordinate models, where it is more consistent with theory, computationally more efficient, easier to implement, and numerically more stable. Assessing the applicability of GL90 in realistic global ocean simulations with hybrid coordinate schemes should be a priority for future work. Plain Language Summary: Ocean models are complex simulations run on large supercomputers, and are useful for predicting changes in ocean circulation and climate. Ocean models divide the globe into grid cells. Choosing many, very small grid cells is not feasible because the simulations would take too much time and would be too expensive. Therefore, the grid cells in most ocean models are not small enough to simulate mesoscale eddies. Mesoscale eddies are swirling motions that are less than 100 km wide and play an important role in transporting heat and carbon throughout the ocean. To still account for the effects of mesoscale eddies, one can use approximate "parameterizations." Which parameterization is "best" is an ongoing research question. This paper compares two parameterizations that simulate the effect of mesoscale eddies in two distinct ways: the commonly used Gent and McWilliams (1990, https://journals.ametsoc.org/view/journals/phoc/20/1/1520-0485%5f1990%5f020%5f0150%5fimiocm%5f2%5f0%5fco%5f2.xml) parameterization and the less commonly used Greatbatch and Lamb (1990, https://journals.ametsoc.org/view/journals/phoc/20/10/1520-0485%5f1990%5f020%5f1634%5fopvmom%5f2%5f0%5fco%5f2.xml?tab%5fbody=abstract-display) parameterization. This paper shows that the two parameterizations impact ocean circulation in a very similar way, and that for a certain class of models the Greatbatch and Lamb (1990, https://journals.ametsoc.org/view/journals/phoc/20/10/1520-0485%5f1990%5f020%5f1634%5fopvmom%5f2%5f0%5fco%5f2.xml?tab%5fbody=abstract-display) parameterization has advantages because it is more consistent with physical and mathematical theory, is easier to code, and leads to faster computations. Key Points: We compare the Greatbatch and Lamb (1990, GL90, https://journals.ametsoc.org/view/journals/phoc/20/10/1520-0485%5f1990%5f020%5f1634%5fopvmom%5f2%5f0%5fco%5f2.xml?tab%5fbody=abstract-display) and the Gent and McWilliams (1990, GM90, https://journals.ametsoc.org/view/journals/phoc/20/1/1520-0485%5f1990%5f020%5f0150%5fimiocm%5f2%5f0%5fco%5f2.xml) parameterizations in an isopycnal ocean modelGL90 leads to very similar flow as GM90, for non‐eddying through eddy‐permitting resolutionWe argue, however, that for isopycnal coordinate models GL90 is more consistent with theory than GM90 [ABSTRACT FROM AUTHOR]

Highlights • We focused on students with special educational needs (SEN) in German primary schools. • SEN students in special schools reported higher motivation than in regular schools. • SEN students who felt more supported by classmates reported higher motivation. • Higher-performing SEN students reported higher motivation. • SEN students' in classrooms with higher achievement levels reported lower motivation. Abstract The present study investigated how the educational placement in special education schools or regular schools is related to the achievement motivation of students with special educational needs (SEN). Furthermore, we examined whether the classroom social environment (i.e., class-average achievement and social support) explains potential placement differences. We compared the academic self-concept and enjoyment of learning of SEN students in special education schools (n = 420) and regular schools (n = 678) at the end of 4th grade. In line with social comparison theory, SEN students in special education schools reported higher academic self-concepts and enjoyment of learning than their peers in regular schools. Examining underlying mechanisms, class-average achievement was negatively related to SEN students' academic self-concept and enjoyment of learning. In contrast, individually perceived social support by classmates—but not class-average social support—was positively associated with SEN students' achievement motivation. After controlling for individual and class-average achievement, no relationship between SEN students' educational placement and achievement motivation was found. Results indicate that social comparisons with classmates may result in placement differences in SEN students' academic self-concept and enjoyment of learning. [ABSTRACT FROM AUTHOR]

Dimensional comparison theory (DCT; Moller & Marsh, 2013) assumes that students compare their academic achievement intraindividually across domains to form domain-specific self-concepts. Upward dimensional comparisons are believed to lead to lower self-concepts in the worse-off domain, while downward dimensional comparisons should lead to higher self-concepts in the better-off domain. Furthermore, DCT assumes the net effect of upward and downward dimensional comparisons to be beneficial to the self. To test these assumptions, 3 experiments and 2 field studies were conducted investigating the relative effects of upward and downward dimensional comparisons as well as their net effect. In Studies 1 (N = 149), 2 (TV = 150) and 3 (N = 300), participants were asked to infer self-concepts of fictitious students after receiving experimentally manipulated information about their achievements in 2 domains, whereas participants in Studies 4 (N = 2,268) and 5 (N = 20,662) assessed their own self-concepts in German and mathematics. In all studies, downward dimensional comparisons resulted in higher self-concepts, whereas upward dimensional comparisons led to lower self-concepts. The net effect of dimensional comparisons was always found to be not statistically different from zero. The findings therefore support the central prediction of DCT on the discreteness of the effects of upward and downward dimensional comparisons, yet do not support the assumed positivity of their net effect. Furthermore, results indicate the effect patterns to be rather universal as they were stable across different samples, domains, achievement situations, research designs, and types of assessment. [ABSTRACT FROM AUTHOR]

Energy exchanges between large-scale ocean currents and mesoscale eddies play an important role in setting the large-scale ocean circulation but are not fully captured in models. To better understand and quantify the ocean energy cycle, we apply along-isopycnal spatial filtering to output from an isopycnal 1/32° primitive equation model with idealized Atlantic and Southern Ocean geometry and topography. We diagnose the energy cycle in two frameworks: 1) a non-thickness-weighted framework, resulting in a Lorenz-like energy cycle, and 2) a thickness-weighted framework, resulting in the Bleck energy cycle. This paper shows that framework 2 is more useful for studying energy pathways when an isopycnal average is used. Next, we investigate the Bleck cycle as a function of filter scale. Baroclinic conversion generates mesoscale eddy kinetic energy over a wide range of scales and peaks near the deformation scale at high latitudes but below the deformation scale at low latitudes. Away from topography, an inverse cascade transfers kinetic energy from the mesoscales to larger scales. The upscale energy transfer peaks near the energy-containing scale at high latitudes but below the deformation scale at low latitudes. Regions downstream of topography are characterized by a downscale kinetic energy transfer, in which mesoscale eddies are generated through barotropic instability. The scale- and flow-dependent energy pathways diagnosed in this paper provide a basis for evaluating and developing scale- and flow-aware mesoscale eddy parameterizations. Significance Statement: Blowing winds provide a major energy source for the large-scale ocean circulation. A substantial fraction of this energy is converted to smaller-scale eddies, which swirl through the ocean as sea cyclones. Ocean turbulence causes these eddies to transfer part of their energy back to the large-scale ocean currents. This ocean energy cycle is not fully simulated in numerical models, but it plays an important role in transporting heat, carbon, and nutrients throughout the world's oceans. The purpose of this study is to quantify the ocean energy cycle by using fine-scale idealized numerical simulations of the Atlantic and Southern Oceans. Our results provide a basis for how to include unrepresented energy exchanges in coarse global climate models. [ABSTRACT FROM AUTHOR]

Inclusive education has become increasingly popular based on the assumption that it has multiple benefits for students with special educational needs (SEN). However, contradictions remain regarding the widespread nature of these benefits, particularly when it comes to academic motivation. In this large-scale cross-sectional study, we relied on the Big-Fish-Little-Pond Effect (BFLPE) to assess the links between inclusive education and students' academic self-concepts and learning interests in the mathematics and verbal domains. The sample consisted of 21,219 German elementary school children in Grade 4 who were enrolled in three groups: students without SEN attending regular schools (n 1 = 19,069), students with SEN attending regular schools (n 2 = 933), and students with SEN attending special education schools (n 3 = 1214). Doubly latent multi-group multilevel structural equation models and tests of latent interaction were performed to test the BFLPE. Results supported the BFLPE for both outcomes and domains. However, no BFLPE was identified for learning interest in the verbal domain among students with SEN attending special education schools, although the size of this effect did not differ significantly from that observed among students without SEN. In regular schools, the BFLPE was almost two times stronger among students with SEN than among their peers without SEN. Results support the generalizability of the BFLPE to students with SEN, while casting doubts on the motivational benefits of inclusive education for these students. Interventions targeted at attenuating the BFLPE should thus be tailored for both regular and special education schools. • We generalize the Big-Fish-Little-Pond Effect to self-concept and learning interest. • We test the BFLPE among students with and without special educational needs. • We test the BFLPE across regular and special education schools, and in mathematics and German. • The BFLPE was supported across outcomes (but stronger for self-concept), subject, and samples. • The BFLPE was stronger for students with special educational needs in regular schools. [ABSTRACT FROM AUTHOR]

This cross-sectional study with N = 21,216 fourth graders (M = 10.50, SD = 0.53) from a large-scale-assessment study in Germany aimed to examine the generalized internal/external frame of reference model (GI/E Model) for academic self-concepts and interests as outcomes of achievement in mathematics and verbal domains. The central objective of this study was to compare the achievement-self-concept/interest relations across three groups of students: n 1 = 19,069 students without special educational needs (SEN) from regular schools, n 2 = 933 students with SEN from regular schools, and n 3 = 1214 students with SEN from special education schools. Results of multi-group structural equation modeling revealed positive within-domain achievement-self-concept/interest relations and negative cross-domain achievement-self-concept/interest relations in all three groups of students. The only non-significant relation was found between verbal achievement and verbal interest of students with SEN in regular and special education schools. Furthermore, there were higher within-domain achievement-self-concept relations in the mathematics domain for students without SEN than for students with SEN and a lower cross-domain relation between mathematics achievement and verbal self-concept for students without SEN than for students with SEN in special education schools. These results indicate that students with and without SEN use both social and dimensional comparisons when evaluating their abilities and interests in mathematics and verbal domains, except for the verbal interest of students with SEN. • Academic achievement, self-concepts, and interests are included in the GI/E model. • The relations in the GI/E model are compared across three student groups. • Students with and without special educational needs (SEN) are included. • Almost all within-domain relations are significantly positive. • All cross-domain relations are significantly negative. [ABSTRACT FROM AUTHOR]

Educational expectations are a key predictor of educational attainment. Throughout adolescence, friends increasingly function as 'significant others' and, thus, can affect the development of these expectations. Although scholars often interpret the clustering of students with similar expectations within friendship networks as the outcome of peer influence, a similarity of friends can also be a result of friendship selection processes and preselection due to ability tracking. We apply multilevel social network models to panel data of adolescents from Germany (1,992 ninth-grade students in 91 classes) to disentangle these mechanisms. Beyond selecting similar friends (homophily), we find that adolescents adapt their expectations towards the average expectations of their friends (social influence) but only in secondary-school tracks that support diverse educational paths. We conclude that peer socialization is important for the development of students' educational expectations in contexts that are sufficiently heterogeneous to allow for the emergence of distinct peer milieus. [ABSTRACT FROM AUTHOR]

The decarbonisation of industry, heating and transportation is a major challenge for many countries' energy transition. Hydrogen is a direct low-carbon fuel alternative to natural gas offering a higher flexibility in the range of possible applications, yet currently most hydrogen is produced using carbon-intensive steam methane reforming due to cost considerations. Therefore, this study explores the economics of a prominent low-carbon method of hydrogen production, comparing the cost of hydrogen generation from offshore wind farms with and without grid electricity imports to conventional hydrogen production methods. A novel techno-economic model for offshore electrolysis production costs is presented, which makes hydrogen production fully dispatchable, leveraging geological salt-cavern storage. This model determines the lifetime costs aportioned across the system components, as well as the Levelised Cost of Hydrogen (LCOH). Using the United Kingdom as a case study, LCOH from offshore wind power is calculated to be €8.68/kg H2 using alkaline electrolysis (AEL), €10.49/kg H2 using proton exchange membrane electrolysis (PEMEL), and €10.88/kg H2 with grid electricity to backup the offshore wind power. A stochastic Monte-Carlo model is used to asses the uncertainty on costs and identify the cost of capital, electrolyser and wind farm capital costs, and cost of electricity as the most important drivers of LCOH across the different scenarios. Reducing the capital cost to comparative levels observed on today's wind farms alone, could see AEL LCOH fall to €5.32/kg H2 , near competitive with conventional generation methods. • Development of a techno-economic model for offshore electrolysis production cost. • Lifetime hydrogen production and Levelized cost of gas (LCOH) are determined. • LCOH is calculated using deterministic and stochastic Monte-Carlo models. • Alkaline electrolysis with offshore wind power cost is the UK's lowest cost option. [ABSTRACT FROM AUTHOR]

Despite the fact that grade retention is now seen as controversial in many quarters, it remains common practice in numerous countries. Previous research on the effects of grade retention on student development has, however, generated ambiguous results, particularly in terms of motivational outcomes. This ambiguity has been attributed in part to a lack of high-quality studies including a longitudinal design, a suitable comparison group, and adequate statistical control of preretention differences. Based on longitudinal data of N = 3,288 German students over 3 years of secondary school, we examined differences in their academic self-concept, scholarly interests, learning motivation, and achievement motivation between those being retained in the 6th grade (n = 61) and those of the same age being promoted annually. To account for confounding variables, we applied full propensity score matching on baseline measures of the dependent variables, as well as various other covariates that have been found to be associated with the risk of retention (e.g., cognitive ability, academic performance, and family background variables). Results reveal a steep decline in students' academic self-concept, interests, and learning motivation during the last months spent in the original class, just before retention. For those measures that were available, negative effects were still partly significant after 1 year, but had diminished 2 years after grade retention. Contrary to predictions suggested by the big-fish-little-pond effect, we found no positive effects of retention on students' academic self-concept. Based on German data, we examined how grade retention in secondary school affects students' motivation not only during the period after retention took place, but also in the period in which decisions on retention are made. We could not find any evidence for positive effects of grade retention on students' motivational development. Instead, we found a considerable decline in students' learning motivation, academic interests and students' beliefs in their academic abilities when they were faced imminent retention at the end of the school year. Accordingly, the results of the present study suggest that, if a student does not reach the criteria for being promoted to the next grade, teachers and parents should provide positive feedback and support to prevent a motivational dip that might be caused by students' anticipation of imminent retention. Furthermore, our study strengthens the evidence that German policymakers need to find alternatives for grade retention. [ABSTRACT FROM AUTHOR]

• Strategy training has a positive effect on transfer of metacognitive strategies. • Combining direct and indirect training did not reveal any differences. • Only a minority of students applied metacognitive strategies. • We conducted a cluster randomized control field study with a large sample. • A first step toward finding ways to promote transfer in self-regulated learning. [ABSTRACT FROM AUTHOR]

Forced migration has become a global megatrend, and many refugees are school aged. As social integration is key to their wellbeing and success, it is pivotal to determine factors that promote the social integration of refugee youth within schools. Here, using a large, nationally representative social network dataset from Germany, we examine the relationships of refugee adolescents with their peers (304 classrooms, 6,390 adolescents and 487 refugees). We find that refugee adolescents have fewer friends and are more often rejected as desk mates than their classmates. Crucially, however, they are less rejected in more diverse classrooms. This results from two basic processes: (1) more opportunities to meet other ethnic minority peers, who are more accepting of refugees in general and (2) higher acceptance of refugee adolescents by ethnic majority peers in more diverse settings. Our results can help promote the social adjustment of young refugees in school and mitigate the negative consequences of prejudice., (© 2023. The Author(s).)

Social comparisons with peers are important sources of self-development during adolescence. Many previous studies showed that students' academic self-concepts (ASC) form by contrasting one's own achievement with the average of one's class or school (the Big-Fish-Little-Pond Effect [BFLPE]). Based on social comparison theory, however, we would expect some peers to be more likely social comparison targets than other peers, for example, because they are more visible or students perceive them as similar to themselves. In this study, we used sociometric data to analyze which peers play the most important role for social comparison effects on ASC. We examined how the average achievement of friends, study partners, peers perceived as popular by the student, as well as same-gender and same-ethnic peers affect the general ASC and how these effects compare to the effect of the classroom's average achievement. The study was based on a German longitudinal sample of 2,438 students (44% no recent immigrant background, 19% Turkish immigrant background, 10% Eastern European immigrant background, 27% other immigrant background) from 117 school classes that were followed from grade 9 to 10. Results from longitudinal social network analysis do not confirm substantial incremental effects of specific types of peers, while class average achievement showed a stable negative effect (confirming the BFLPE). In addition, we could provide evidence for social selection effects based on ASC. We conclude that classrooms provide a specific setting that imposes social comparisons with the "generalized peer" rather than with specific subgroups of peers. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Earth system models (ESMs) project that global warming suppresses biological productivity in the Subarctic Atlantic Ocean as increasing ocean surface buoyancy suppresses two physical drivers of nutrient supply: vertical mixing and meridional circulation. However, the quantitative sensitivity of productivity to surface buoyancy is uncertain and the relative importance of the physical drivers is unknown. Here, we present a simple predictive theory of how mixing, circulation, and productivity respond to increasing surface buoyancy in 21st-century global warming scenarios. With parameters constrained by observations, the theory suggests that the reduced northward nutrient transport, owing to a slower ocean circulation, explains the majority of the reduced productivity in a warmer climate. The theory also informs present-day biases in a set of ESM simulations as well as the physical underpinnings of their 21st-century projections. Hence, this theoretical understanding can facilitate the development of improved 21st-century projections of marine biogeochemistry and ecosystems., Competing Interests: The authors declare no competing interest.