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Fluorenyl-tethered N-heterocyclic carbene complexes of the heavy alkali metals
Full text linkThe coordination chemistry of N-heterocyclic carbenes (NHCs) with Group 1 metals remains comparatively underdeveloped relative to their extensive application across the periodic table. Herein, we describe the synthesis of rubidium and caesium complexes incorporating a fluorenyl-tethered NHC ligand. Additionally, the first heterobimetallic Cs/Li NHC complex was obtained via treatment with a combination of alkali metal amide bases
Variable-mass gravity tractor for asteroid deflection : full mission process optimization and deflection efficiency analysis
No full textThe Gravity Tractor (GT) is a spacecraft that deflects an asteroid using its gravitational force to gradually alter the asteroid’s trajectory without making physical contact. This paper proposes a comprehensive mission optimization framework to maximize orbital deflection distance in variable-mass GT missions, incorporating key constraints: launch performance, warning time, and operational strategies. Simulation results suggest that the deflection distance of GT does not increase linearly with warning time due to launch window constraints, and the three-pulse transfer scenario does not provide significantly greater deflection distance compared to the two-pulse transfer scenario. Moreover, in the static hovering scenario, the deflection distance first increases and then decreases with the effective tractor distance, whereas in the displaced orbit scenario, it decreases monotonically. Finally, considering the launch performance of CZ-5, a 10-year warning time enables the defense against 50-meter asteroids, while a 20-year warning time enables the defense against 100-meter asteroids. This research provides valuable insights into the evaluation of GT deflection efficiency and the engineering design of GT-based missions
Atomic spectrometry update : review of advances in environmental analysis
Full text linkHighlights in the field of air analysis included: development of laboratory-based particle emission simulators to emulate real-world processes such as tyre-wear abrasion; ongoing performance verification of Hg calibrators; progress in laser and spark emission spectroscopic techniques for in situ aerosol measurements, advances in data processing software tools in supporting sp-ICP-MS measurements, feasibility of using aerosol mass spectrometers for measuring nanoplastics in air, and a comprehensive review of brown carbon aerosols, its sources, optical properties and measurement approaches used. While recent developments in water analysis include significant progress in sp-ICP-MS, including the introduction of new measurement protocols, determination of isotope ratios, and new reference materials. The number of studies employing LIBS for assessing metal burdens in water has also grown notably, particularly with respect to innovations in sample preparation. Advances were further reported in the development of portable analytical devices and systems for continuous environmental water monitoring. In addition, several comprehensive reviews were published, providing guidance for researchers on establishing robust measurement workflows, including split-stream and sp-ICP-MS methodologies. In the analysis of plants and soils, there has been increased interest in deep eutectic solvents as milder and greener alternatives to traditional extractants. Microwave plasma torch mass spectrometry methods have been developed that allowed concurrent measurement of trace elements and organic pollutants in liquid samples. Promising steps have also been taken towards application of techniques for direct analysis of solids. Advances in LIBS have largely focussed on data processing and modelling whilst in XRF, the influence of soil matrix composition on measurement accuracy was highlighted. Quantitative geochemical analysis faces continuous challenges, making the development of new RMs a persistent priority, especially for localized microanalysis. Application of LIBS is gaining increasing interest because of its portability and the use of machine learning tools to improve the quality of the obtained data. Interest is also increasing in the analysis of extraterrestrial samples. Novel ICP-MS instrumentation has offered highly precise isotopic analysis and spectral interference removal. Other important techniques in this review period have been nanoSIMS, NAA, and MS variants because they may provide new and enhanced chemical information. The fusion of data and the significantly increasing application of AI for rapid mineral identification and data integration marks a key trend that is expected to grow exponentially
Water in computable general equilibrium models : review, synthesis and avenues for future research
No full textWater-extended Computable General Equilibrium (CGE) models are a class of economy-wide models widely used as tools to address research and policy questions for various water-related topics. This systematic review analyses 100 applications of water-CGE models, categorising them into key areas based on their structure and aims, including agricultural, industrial, combination of agricultural and industrial, energy, and combination of energy and agriculture, to examine the methodological approaches of incorporating water into CGE models, and to explore the various themes of the applications. Findings suggest that improvements in incorporating water in CGE models require improvements in the quality and detail of water data, explicitly specifying water as a factor of production, constructing models at smaller spatial scales, accounting for water seasonality, and improving transparency of calibration and validation methods. Addressing these challenges will enhance the representation of water in CGE models that can provide critical insights in addressing water-economy interconnections
Understanding pathways to low educational attainment : a multidimensional poverty and educational achievement model
No full textWhile the link between poverty and educational achievement is well-established, the mechanisms through which poverty impacts learning remain poorly understood, particularly in low- and middle-income countries (LMICs). This study explores the pathways from poverty to educational attainment in two LMIC contexts – Ghana and Malawi. We employed a qualitative multi-perspectival research design, conducting in-depth interviews with 103 participants in both Ghana and Malawi, including pupils (n=34), teachers (n=31), headteachers (n=11), education advisors (n=8), and parents (n=19) from schools with historically low academic performance. These schools primarily serve pupils living in poverty. Using a semi-structured interview approach, we elicited participants understandings of the factors and mechanisms that account for low educational achievement of pupils from economically disadvantaged backgrounds. The qualitative data were analysed using the grounded theory method to identify key concepts and develop a theoretical understanding of how poverty influences achievement. We present a Multidimensional Poverty and Educational Achievement Model (MPEAM) that identifies three key dimensions of poverty – school resources, household conditions, and accessibility. These dimensions affect educational outcomes by shaping the learning environment, influencing learner participation and concentration, contributing to absenteeism, and limiting interactions among pupils, teachers, and communities. The study offers new insights into the complex, context-specific pathways linking poverty to educational outcomes. It highlights the need for integrated policies and interventions that address the multifaceted nature of poverty to support improved learning for socioeconomically disadvantaged learners
Trajectories of mental health difficulties from childhood to adolescence : evidence from growing up in Ireland
No full textMany mental health difficulties first emerge in adolescence and can have lasting impacts on later-life outcomes. In this paper, we focus on young people’s mental health difficulties, as measured by the internalising and externalising difficulties subscales of the Strengths and Difficulties Questionnaire (SDQ). Using data from two cohorts of Growing Up in Ireland (GUI), we use group-based modelling techniques to examine how internalising and externalising difficulties evolve between the ages of 3 and 13 for the ’08 Cohort, and between the ages of 9 and 17 for the ’98 Cohort. We also focus on the key transition point of age 9 to 13, contrasting the experiences of young people from the two cohorts, born 10 years apart. The results indicate that most young people in Ireland display low levels of mental health difficulties, but that there is considerable change over time, and some young people experience persistently high levels of mental health difficulties. Consistent with prior research, girls display higher rates of internalising difficulties, while boys display higher rates of externalising difficulties. When comparing these difficulties across both cohorts between the ages of 9 and 13, we find an increase in internalising difficulties (most pronounced among girls) for the ’08 Cohort, in contrast to a decline between these ages for the ’98 Cohort. As further waves of the ’08 Cohort become available, it will be important to determine whether this reflects an earlier increase in young people’s internalising difficulties which continues beyond the age of 13, or whether this stabilises or possibly declines. The findings add to the emerging literature on how young people’s mental health difficulties vary by age and gender, and how internalising difficulties in particular have increased in recent times
Using a systems thinking approach to assess the complex interplay between sustainable development goals, climate change, and humanitarian operations
Full text linkClimate change consequences, such as severe droughts, water shortages, wildfires, rising sea levels, floods, polar ice melt, catastrophic storms, and biodiversity loss, significantly impact the achievement of the SDGs. These adverse effects exacerbate the frequency and magnitude of disasters, thereby increasing the need for effective HOs and disaster management policies. HOs are essential for balancing short-term emergency responses with long-term economic and social development interventions. Considering this context, we develop a systems thinking approach to identify key interconnections and intervention points at the intersection of climate change (CC), the sustainable development goals (SDGs), and humanitarian operations (HOs), using a systematic literature review (SLR) and causal loop diagrams (CLDs). These diagrams provide a visual representation of how different variables interact, allowing for a deeper understanding of where interventions can be most effective. This holistic approach is crucial for achieving the long-term goals of resilience and sustainability in the face of growing climate challenges. Additionally, we use heat maps to depict the intensity and distribution of relationships across different variables. Key findings highlight the need for innovative policies that integrate nature-based solutions and advanced climate data analytics to strengthen disaster preparedness and response. For example, reducing greenhouse gas (GHG) emissions stands out as a strategic leverage point that simultaneously contributes to climate change mitigation, disaster risk reduction, and progress across multiple SDGs. Moreover, the findings underscore the importance of advancing carbon sequestration techniques to mitigate climate change impacts effectively. Addressing these research gaps can contribute to developing more effective strategies for managing climate risks and promoting sustainable development
What is the connection between employee voice and job quality?
No full textThough concerns with job quality have a long genesis in social science research, the subject has gained increased attention from policymakers in recent decades. Job quality is a multidimensional concept and a multidisciplinary area of research. The core concern of this chapter is the connection between employee voice and job quality, an area which is underemphasized in job quality debates. The focus is primarily upon the experience of the UK, a nation which has achieved strong employment levels in recent decades but where concerns have increasingly been expressed by various stakeholders regarding the quality of jobs. The chapter therefore considers the relationship between employee voice and job quality by reviewing current evidence before considering the implications for the future. The key argument is that, to improve understanding and policymaking in the context of developments in working patterns, a better theorization and conceptualization of voice and its relationship with job quality is necessary
Temporal associations of physical activity volume, intensity, and timing with sleep in preschool‐aged children
Full text linkThis study aimed to investigate the temporal relationships between accelerometer‐derived physical activity metrics—specifically volume, intensity, and timing—with the preceding and subsequent nights' sleep in preschool‐aged children. This analysis used the baseline data from a randomised controlled trial among 93 children (53 boys) aged 3–5.9 years who provided daily, repeated measures for at least four days. Open‐source R package GGIR was used to generate daily measures of average acceleration, intensity gradient, timing of the most active 10 h (M10 start), sleep duration, sleep efficiency, and sleep midpoint. Linear mixed models were performed to examine temporal associations between waketime physical activity and the subsequent night's sleep, and between nocturnal sleep and physical activity the following day, at both within‐ and between‐person levels. A higher intensity gradient compared to the personal average during the day predicted a lower sleep efficiency on the subsequent night (β = −10.71, 95% CI: −17.20, −4.21). At the between‐person level, children with longer sleep duration (β = 0.87, 95% CI: 0.45, 1.29), a later sleep midpoint (β = 1.03, 95% CI: 0.79, 1.27), or lower sleep efficiency (−0.09, 95% CI: −0.14, −0.03) were more likely to have their active periods later in the following day. These findings suggest that the timing of physical activity and sleep midpoint showed consistent bidirectional associations at both within‐ and between‐person levels. The findings suggest that incorporating lower intensity activities that are scheduled at appropriate times into daily routines may be crucial for better sleep for young children
Carbon nitride thin-film planar heterojunctions for photoelectrocatalytic C–N coupling
Full text linkTransitioning traditional chemical processes into a more sustainable, low carbon impact model is of utmost priority to mitigate the pressing issue of global environmental change. Photoelectrocatalysis, which combines photocatalysis and electrocatalysis to further lower energy consumption and to engage on challenging chemicals, is a viable and powerful solution. Here, we introduce a strategy to stabilize and enhance the reactivity of carbon nitride thin-film-based photoelectrodes by introducing a conductive layer in between the thin film and its substrate to form a planar heterojunction electrode. The as-prepared photoelectrodes were fabricated and applied for the oxidation of benzylamine with high selectivity towards N-benzylideneamine and improved reusability. Furthermore, we expanded the scope of reactions to prepare the more synthetically challenging and pharmaceutically relevant 3,6-diphenylpyridazines from 1,4-diphenylbutane-1,4-dione. The results indicated that the CN thin-film-based photoelectrodes demonstrated excellent performances with good selectivity toward oxidation products, using only less than 1 mg of carbon nitride catalyst, achieved by effective engineering of the interfaces
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