Assessment of coastal and marine ecosystems in West Africa: The case of Ghana.

Coastal and marine ecosystems, as integral component of social, ecological, and economic systems, are critical in providing essential ecosystem services that underpin human activities, including fishing and mining. Effective management of these ecosystems is paramount to safeguarding their vital contributions. This study adopts a socio-ecological framework, "Drivers (D) of human activities (A), associated Pressures (P), State change in coastal and marine environments, Impact (I) on human welfare (W) and Response (R) as measures (M) of management, (DAPSI(W)R(M))," to analyse the complexities of coastal and marine ecosystems in the Ghanaian context. The study identifies various drivers of anthropogenic activities, such as fishing, oil and gas production, and waste disposal. These anthropogenic activities create significant pressures, including selective extraction of living and non-living resources, as well as habitat degradation through substratum loss and pollution. Consequently, these pressures have led to changes in fish biomass and habitat quality, among other ecological shifts.

Lhx6 activity is required for the normal migration and specification of cortical interneuron subtypes.

The cerebral cortex contains two main neuronal cell populations, the excitatory glutamatergic (pyramidal) neurons and the inhibitory interneurons, which synthesize GABA and constitute 20-30% of all cortical neurons. In contrast to the mostly homogeneous population of projection neurons, cortical interneurons are characterized by remarkable morphological, molecular, and functional diversity. Among the markers that have been used to classify cortical interneurons are the calcium-binding proteins parvalbumin and calretinin and the neuropeptide somatostatin, which in rodents identify mostly nonoverlapping interneuron subpopulations. Pyramidal neurons are born during embryogenesis in the ventricular zone of the dorsal telencephalon, whereas cortical interneurons are generated in the subpallium and reach the cortex by tangential migration. On completion of tangential migration, cortical interneurons switch to a radial mode of migration and enter the cortical plate. Although the mechanisms that control the generation of interneuron diversity are currently unknown, it has been proposed that their site of origin in the ventral forebrain determines their specification into defined neurochemical subgroups. Here, we show that Lhx6, a gene induced in the medial ganglionic eminence and maintained in parvalbumin- and somatostatin-positive interneurons, is required for the specification of these neuronal subtypes in the neocortex and the hippocampus. We also show that Lhx6 activity is required for the normal tangential and radial migration of GABAergic interneurons in the cortex.