Preparation of iron(IV) nitridoferrate Ca₄FeN₄ through azide-mediated oxidation under high-pressure conditions

Transition metal nitrides are an important class of materials with applications as abrasives, semiconductors, superconductors, Li-ion conductors, and thermoelectrics. However, high oxidation states are difficult to attain as the oxidative potential of dinitrogen is limited by its high thermodynamic stability and chemical inertness. Here we present a versatile synthesis route using azide-mediated oxidation under pressure that is used to prepare the highly oxidised ternary nitride Ca4FeN4 containing Fe4+ ions. This nitridometallate features trigonal-planar [FeN3]5− anions with low-spin Fe4+ and antiferromagnetic ordering below a Neel temperature of 25 K, which are characterised by neutron diffraction, 57Fe-Mössbauer and magnetisation measurements. Azide-mediated high-pressure synthesis opens a way to the discovery of highly oxidised nitrides.</p

Exploring service providers’ perspectives on the prevention and management of fetal alcohol spectrum disorders in South Africa: a qualitative study

BACKGROUND: Fetal alcohol spectrum disorder (FASD) is among the leading causes of developmental and intellectual disabilities in individuals. Although efforts are being made toward the prevention and management of FASD in South Africa, the prevalence remains high. The sustained high prevalence could be attributed to several factors, including the lack of policy for a coordinated effort to prevent, diagnose and manage FASD nationally. In this study, our aim was to explore the perspectives of service providers (health and allied professionals, teachers, social workers) on the prevention and management of FASD towards developing a guideline to inform policy. METHOD: Guided by the exploratory qualitative research design, we purposively sampled relevant service providers in the field of FASD prevention and management for focus group discussions. Nine of these discussions were conducted with to eight participants per discussion session. The discussants were asked various questions on the current and required interventions and practices for the prevention and management of FASD. Following the Framework Method, data were transcribed verbatim and analysed using the thematic content analysis approach. RESULTS: Our findings show that aspects of the prevention and management of alcohol-related conditions are present in various policies. However, there is no clear focus on coordinated, multi-sectoral efforts for a more comprehensive approach to the prevention and management of FASD. The participants recognized the need for specific requirements on broad-based preventive awareness programs, training and support for parents and caregivers, inclusive education in mainstream schools and training of relevant professionals. CONCLUSION: Comprehensive and coordinated prevention and management programs guided by a specific policy could improve the prevention and management of FASD. Policy formulation demonstrates commitment from the government, highlights the importance of the condition, and elaborates on context-specific prevention and management protocols.IS

Root-derived organic matter confines sponge community composition in mangrove ecosystems

IntroductionCaribbean mangrove-associated sponge communities are very distinct from sponge communities living on nearby reefs, but the mechanisms that underlie this distinction remain uncertain. It has been hypothesized that dissolved organic matter (DOM) leaching from mangrove roots and the ability of mangrove-associated sponge-bacterial consortia to degrade mangrove DOM may cause this distinction.MethodsThis study tested whether mangrove DOM, leaching from mimicry substrates or directly injected in sponge tissue, affected the performance of a reef and a mangrove sponge species.ResultsControls and the mangrove sponge remained unaffected by mangrove DOM leaching from mimicry substrates or directly injected in sponge tissue, but the reef species showed substantial necrosis when exposed to mangrove DOM.ConclusionsResults presented in this study suggest that mangrove DOM confines the composition of sponge communities in mangrove ecosystems, explaining the exclusion of typical reef species and the adjacent occurrence of distinct sponge communities