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For a multidimensional Itô semimartingale, we consider the problem of estimating integrated volatility functionals. Jacod and Rosenbaum (2013, The Annals of Statistics 41(3), 1462–1484) studied a plug-in type of estimator based on a Riemann sum approximation of the integrated functional and a spot volatility estimator with a forward uniform kernel. Motivated by recent results that show that spot volatility estimators with general two-sided kernels of unbounded support are more accurate, in this article, an estimator using a general kernel spot volatility estimator as the plug-in is considered. A biased central limit theorem for estimating the integrated functional is established with an optimal convergence rate. Central limit theorems for properly de-biased estimators are also obtained both at the optimal convergence regime for the bandwidth and when applying undersmoothing. Our results show that one can significantly reduce the estimator’s bias by adopting a general kernel instead of the standard uniform kernel. Our proposed bias-corrected estimators are found to maintain remarkable robustness against bandwidth selection in a variety of sampling frequencies and functions.

The climate crisis is one of the greatest challenges of our time, yet the role of microorganisms remains underrecognized in climate science and policy. Microbes are highly sensitive to environmental change and regulate essential biogeochemical processes, while also offering solutions for reducing emissions, restoring ecosystems, and enhancing resilience. Microbiology societies from five continents recently convened in Washington, DC, for the inaugural Global Strategy Meeting on Microbes and Climate Change. The gathering launched a global alliance to position microbial science as a pillar of climate action and identified four priorities: building a coalition, embedding microbes in climate frameworks, transforming communication, and advancing real-world demonstration projects. This initiative marks the beginning of coordinated global action to harness microbial life for climate solutions.

This study examines the vulnerability of smallholder farming households to climate change and variability (CCV) in Nandom District in semi-arid northwestern Ghana. It also assesses farmers' perceptions about agroecosystem services, climate information, and their well-being. The main objective of the study is to gather detailed information for developing policies. Therefore, models of the livelihood vulnerability index (LVI) and those of the LVI-Intergovernmental Panel for Climate Change (LVI-IPCC) were fitted to collected data, which covered a 31-year period. The LVI approach shows that vulnerability of smallholder farmers' livelihoods to climate change and variability (CCV) is significantly different among the farming communities in the study area of Nandom District in terms of their sociodemographic profile, food, water, and health. The combined LVI and LVI-IPCC concepts show that the impacts of CCV on smallholder farmers' livelihoods vary across these communities. Where agroecosystem services and climate information are sufficiently available, they appear to be the most significant determinants of effective adaptation practices resisting CCV. However, several factors, including low rainfall, bush burning, clear cutting, and floods, among others, are perceived by smallholder farmers as causes of the decline in agroecosystem services, prompting the farmers to express differentiated views about their well-being across communities in Nandom District. Thus, the vulnerability of smallholder farmers' adaptations are linked to the declining agroecosystem services and/or the variation in information about climate in the study area. Consideration of development policies and plans is imperative for sustainably improving adaptive capacity and livelihood strategies of smallholder farmers in the semi-arid zone.

Systemic autoantibody-mediated diseases accelerate chronic cardiovascular disease in humans. In the K/B.g7 mouse model of spontaneous autoantibody-mediated inflammatory arthritis, valvular carditis arises in part because of Fc receptor-mediated activation of macrophages, leading to production of pathogenic TNF and IL-6. In this study, we explored whether impaired efferocytosis mediated by the interaction of CD47-expressing apoptotic cells with signal regulatory protein α (SIRPα) on macrophages contributes to disease progression in this model. CD47-expressing apoptotic cells and SIRPα+ macrophages were abundant in inflamed/rheumatic cardiac valves from both mice and humans. In vivo anti-CD47 blockade both prevented and treated valvular carditis in K/B.g7 mice. Blocking CD47 enhanced macrophage efferocytosis and reduced macrophage production of TNF and IL-6. These studies highlight the CD47:SIRPα interaction as a key driver of chronic cardiac valve inflammation and suggest these molecules as potential therapeutic targets to reduce cardiovascular disease risk in autoantibody-driven inflammatory diseases.

Abstract West Africa has plentiful renewable energy (RE) resources with potential to support economic growth, but numerous energy-related challenges persist. Rural areas are heavily reliant on biomass for everyday needs, and the region has a history of extreme events, including the severe drought in the 1970s and 80s, that impact water availability and access, agricultural productivity and food security. Despite a number of recent programs, energy transitions in the region remain poorly understood. With this motivation, START implemented the Promoting Gains in Renewable Energy project (ProGREEN) in West Africa to identify key enabling and constraining factors for the development and spread of RE, and for recognizing the broader development outcomes linked to RE access. During 2019, ProGREEN gathered multisector and multidisciplinary experts from Burkina Faso and Senegal to embark on an integrative and participatory assessment effort including an intensive literature review, individual interviews, and focus group discussions with grassroots actors of decentralized RE projects. The assessment found access to RE in remote areas was enabled by numerous factors including availability of RE sources, government efforts to improve policy and regulatory frameworks, and falling prices of solar equipment. RE access is found to bring significant improvements to the living conditions of local communities. However, insufficient funds, too few qualified technicians, lacking quality control for equipment, and insufficient engagement of local communities were found to hinder RE development. Findings suggest sharpening technical and financial skills, updating best practices, and integrating research development and cooperation among actors in the renewable energy field.KeywordsConstraining and enabling factorsWater accessAgriculture productivity and food securityGreen economy

Introduction To support the development of practices and guidelines that might help toreduce adverse events related to human factors, we aimed to study theresponse and perception by members of a cardiovascular surgery team ofvarious error-driven or adverse features that might arise in the operatingroom (OR).Methods A previously validated Disruptions in Surgery Index (DiSI) questionnaire wascompleted by individuals working together in a cardiovascular surgical unit.Results were submitted to reliability analysis by calculating the Cronbach’salpha coefficient. Non-parametric Kruskal-Wallis test and Dunn’s post-testwere performed to estimate differences in perceptions of adverse events oroutcomes between the groups (surgeons, nurses, anesthesiologists, andtechnicians). P<0.05 was considered statisticallysignificant.Results Cronbach’s alpha reliability coefficients showed consistency within therecommended range for all disruption types assessed in DiSI: an individual’sskill (0.85), OR environment (0.88), communication (0.81), situationalawareness (0.92), patient-related disruption (0.89), team cohesion (0.83),and organizational disruption (0.83). Nurses (27.4%) demonstratedsignificantly higher perception of disruptions than surgeons (25.4%),anesthetists (23.3%), and technicians (23.0%) (P=0.005).Study participants were more observant of their colleagues’ disruptivebehaviors than their own (P=0.0001).Conclusion Our results revealed that there is a tendency among participants to hold apositive self-perception position. DiSI appears to be a reliable and usefultool to assess surgical disruptions in cardiovascular OR teams, identifyingnegative features that might imperil teamwork and safety in the OR. Andhuman factors training interventions are available to develop team skillsand improve safety and efficiency in the cardiovascular OR.

ABSTRACT Semi-Arid Regions (SARs) of West Africa are considered climate change “hotspots” where strong ecological, economic and social impacts converge to make socio-ecological systems particularly vulnerable. While both climatic and non-climatic drivers interact across scales to influence vulnerability, traditionally, this inter-connectedness has received little attention in vulnerability assessments in the region. This study adopted the vulnerability patterns framework, operationalized using the Multidimensional Livelihood Vulnerability approach to include both climatic and non-climatic stressors to analyze differential household vulnerability in SARs of Mali. Findings showed that while drought was the most mentioned climate-related stressor, households were also exposed to a diversity of environmental and socio-economic stressors, including food scarcity, livestock disease, labour unavailability, crop damage, and erratic rainfall patterns. The typology revealed three vulnerability archetypes differentiated by adaptive capacity and sensitivity. Availability of productive household members, household resource endowments, livelihood diversification and social networks were the main discriminant factors of household adaptive capacity, while challenges relating to food and water security make households more sensitive to stressors. The analysis highlighted the heterogeneity in household vulnerability patterns within and across communities. Failing to account for this heterogeneity in adaptation planning might result in a mismatch between adaptation needs and interventions, and potentially in maladaptation.

Abstract Though there is increasing recognition of the cultural dimensions that shape climate change adaptation, our experience from working with actors engaged in adaptation policy and practice suggests that the role of culture still tends to be conceived in overly narrow and fixed terms. This is exemplified in portrayals of conservative cultural norms as stifling positive change. A growing body of research across the world indicates that the reality is seldom as simple as this—culture works in complex and variable ways, and, most importantly, is inherently dynamic. Drawing especially from research work on vulnerability and adaptation conducted in semi‐arid regions, we illustrate this argument by briefly exploring three themes—multiple knowledge systems for farming in Botswana, the dynamics of pastoralist values and livelihoods in Kenya, and the interplay of caste and livelihood choices in India. Understanding how different facets of culture such as these operate in context helps move away from viewing culture statically as a barrier or enabler, and toward a more plural and dynamic appreciation of the role of culture in adaptation. This includes recognizing the potential for factors that may be construed as barriers to become enablers. Critical, balanced engagement with cultural dimensions in both research and practice, understanding and working with these dynamic social structures, is essential if adaptation is to create meaningful and lasting change for those who need it most.This article is categorized under:Vulnerability and Adaptation to Climate Change &gt; Values‐Based Approach to Vulnerability and Adaptation