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The response properties, connectivity and function of the cingulate sulcus visual area (CSv) are reviewed. Cortical area CSv has been identified in both human and macaque brains. It has similar response properties and connectivity in the two species. It is situated bilaterally in the cingulate sulcus close to an established group of medial motor/premotor areas. It has strong connectivity with these areas, particularly the cingulate motor areas and the supplementary motor area, suggesting that it is involved in motor control. CSv is active during visual stimulation but only if that stimulation is indicative of self-motion. It is also active during vestibular stimulation and connectivity data suggest that it receives proprioceptive input. Connectivity with topographically organized somatosensory and motor regions strongly emphasizes the legs over the arms. Together these properties suggest that CSv provides a key interface between the sensory and motor systems in the control of locomotion. It is likely that its role involves online control and adjustment of ongoing locomotory movements, including obstacle avoidance and maintaining the intended trajectory. It is proposed that CSv is best seen as part of the cingulate motor complex. In the human case, a modification of the influential scheme of Picard and Strick (Picard and Strick, Cereb Cortex 6:342–353, 1996) is proposed to reflect this.

IntroductionXenophyophores are large benthic agglutinated Foraminifera that are a major component of the Clarion-Clipperton Zone megafauna.MethodsTwo xenophyophore specimens were obtained and submitted to genomic investigations.ResultsFor both specimens, it was possible to obtain a ca. 25 kb circular xenophyophore-associated mitochondrial genome (XAM) showing similar gene contents with other Retaria, with which they are associated by a maximum likelihood multiprotein phylogeny. One of the specimens yielded a complete cluster of nuclear rRNA genes, the first to be obtained from a xenophyophore. Another full cluster of rRNA, likely belonging to Endomyxa parasites, was found within both specimens.DiscussionAlthough the agglutinated nature of xenophyophores currently prevents a definitive conclusion, the mitogenomes obtained may represent the first to be obtained from those foraminifera. Deeper enquiries are required in order to properly ascribe these genomes to their host organism and to clarify the nature of the possibly parasitic Rhizaria associated with the xenophyophores.

The abyssal seafloor in the Clarion-Clipperton Zone (CCZ) in the NE Pacific hosts the largest abundance of polymetallic nodules in the deep sea and is being targeted as an area for potential deep-sea mining. During nodule mining, seafloor sediment will be brought into suspension by mining equipment, resulting in the formation of sediment plumes, which will affect benthic and pelagic life not naturally adapted to any major sediment transport and deposition events. To improve our understanding of sediment plume dispersion and to support the development of plume dispersion models in this specific deep-sea area, we conducted a small-scale, 12-hour disturbance experiment in the German exploration contract area in the CCZ using a chain dredge. Sediment plume dispersion and deposition was monitored using an array of optical and acoustic turbidity sensors and current meters placed on platforms on the seafloor, and by visual inspection of the seafloor before and after dredge deployment. We found that seafloor imagery could be used to qualitatively visualise the redeposited sediment up to a distance of 100 m from the source, and that sensors recording optical and acoustic backscatter are sensitive and adequate tools to monitor the horizontal and vertical dispersion of the generated sediment plume. Optical backscatter signals could be converted into absolute mass concentration of suspended sediment to provide quantitative data on sediment dispersion. Vertical profiles of acoustic backscatter recorded by current profilers provided qualitative insight into the vertical extent of the sediment plume. Our monitoring setup proved to be very useful for the monitoring of this small-scale experiment and can be seen as an exemplary strategy for monitoring studies of future, upscaled mining trials. We recommend that such larger trials include the use of AUVs for repeated seafloor imaging and water column plume mapping (optical and acoustical), as well as the use of in-situ particle size sensors and/or particle cameras to better constrain the effect of suspended particle aggregation on optical and acoustic backscatter signals.

Recently, several interesting constructions of vectorial Boolean functions with the maximum number of bent components (MNBC functions, for short) were proposed. However, many of them have component functions from the completed Maiorana-McFarland class M # . Moreover, no examples of MNBC functions containing component functions provably outside M # are known. In this paper, we classify all MNBC functions in six variables. Based on the analysis of the obtained equivalence classes, we propose several infinite families of MNBC functions with component functions outside the M # class. In particular, two of our new constructions are solutions to the open problem [Bapić et al (eds) Proceedings of the twelfth international workshop on coding and cryptography, 2022, Item 1., p. 9].

The Clarion Clipperton Zone (CCZ) of the Eastern Pacific is an ~ 6 million km 2 abyssal area punctuated by seamounts. The CCZ is a focus for potential mining, although this is not, as yet, a commercial reality. Records from online repositories and field guides suggest that up to 30 cetacean species are present in the CCZ, though dedicated surveys have yet to be published. We report the results of a passive acoustic survey for cetaceans conducted over 13 days during summer 2023 in two blocks of the CCZ earmarked for deep seabed mining – NORI-d and TOML-e. The areas surveyed had a mean depth of 4259 m, with no charted seamounts, with 4,328 km of survey effort (273 hours of continuous recordings). In total, there were 74 acoustic detections, with six visual encounters. We report the presence of a sperm whale ( Physeter macrocephalus ) (one individual), Risso’s dolphins ( Grampus griseus ) (two groups) and common dolphins ( Delphinus delphis ) (one group, confirmed by visual sighting). We also acoustically encountered 70 dolphin groups that could not be identified to species level. No baleen whales, kogiids or beaked whales were detected during this short survey. Beaked whales are challenging to detect, such that a lack of detections cannot be taken to confirm the absence of such species. We confirm one threatened species present in these blocks of the CCZ – sperm whales – and suggest that more extensive data are urgently needed to understand the risk of harm to cetaceans that may arise from human activities, including deep-sea mining.

Seamounts are common in all ocean basins, and most have summit depths >3,000 m. Nonetheless, these abyssal seamounts are the least sampled and understood seamount habitats. We report bait-attending community results from the first baited camera deployments on abyssal seamounts. Observations were made in the Clarion Clipperton Zone (CCZ), a manganese nodule region stretching from south of Hawaii nearly to Mexico. This zone is one of the main target areas for (potential) large-scale deep-sea nodule mining in the very near future. The Seamount Refuge Hypothesis (SRH) posits that the seamounts found throughout the CCZ provide refugia for abyssal fauna likely to be disturbed by seabed mining, yielding potential source populations for recolonization of mined areas. Here we use baited cameras to test a prediction of this hypothesis, specifically that predator and scavenger communities are shared between abyssal seamounts and nearby abyssal plains. We deployed two camera systems on three abyssal seamounts and their surrounding abyssal plains in three different Areas of Particular Environmental Interests (APEIs), designated by the International Seabed Authority as no-mining areas. We found that seamounts have a distinct community, and differences in community compositions were driven largely by habitat type and productivity changes. In fact, community structures of abyssal-plain deployments hundreds of kilometers apart were more similar to each other than to deployments ∼15 km away on seamounts. Seamount communities were found to have higher morphospecies richness and lower evenness than abyssal plains due to high dominance by synaphobranchid eels or penaeid shrimps. Relative abundances were generally higher on seamounts than on the plains, but this effect varied significantly among the taxa. Seven morphotypes were exclusive to the seamounts, including the most abundant morphospecies, the cutthroat eel Ilyophis arx. No morphotype was exclusive to the abyssal plains; thus, we cannot reject the SRH for much of the mobile megafaunal predator/scavenging fauna from CCZ abyssal plains. However, the very small area of abyssal seamounts compared to abyssal plains suggest that seamounts are likely to provide limited source populations for recolonizing abyssal plains post-mining disturbance. Because seamounts have unique community compositions, including a substantial number of predator and scavenger morphospecies not found on abyssal plains, they contribute to the beta biodiversity of the Clarion-Clipperton Zone, and thus indirect mining impacts on those distinct communities are of concern.

This is a contribution in a series of taxonomic publications on benthic fauna of polymetallic nodule fields in the eastern abyssal Clarion-Clipperton Zone (CCZ). The material was collected during environmental surveys targeting exploration contract areas ‘UK-1’, ‘OMS’ and ‘NORI-D’, as well as an Area of Particular Environmental Interest, ‘APEI-6’. The annelid families Amphinomidae and Euphrosinidae are investigated here. Taxonomic data are presented for six species from 41 CCZ-collected specimens as identified by a combination of morphological and genetic approaches; of the six species, three are here described as new, one species is likely to be new but in too poor condition to be formalised and the two others likely belong to known species. Description of three new species Euphrosinella georgievae sp. nov. , Euphrosinopsis ahearni sp. nov. , and Euphrosinopsis halli sp. nov. increases the number of formally described new annelid species from the targeted areas to 21 and CCZ-wide to 52. Molecular data suggest that four of the species reported here are known from CCZ only, but within CCZ they have a wide distribution. In contrast, the species identified as Bathychloeia cf. sibogae Horst, 1910 was found to have a wide distribution within the Pacific based on both morphological and molecular data, using comparative material from the abyssal South Pacific. Bathychloeia cf. balloniformis Böggemann, 2009 was found to be restricted to APEI-6 based on DNA data available from CCZ specimens only, but morphological data from other locations suggest potentially a wide abyssal distribution. The genus Euphrosinopsis was previously known only from Antarctic waters, and Euphrosinella georgievae sp. nov. was recovered as a sister taxon to the Antarctic specimens of Euphrosinella cf. cirratoformis in our molecular phylogenetic analysis, strengthening the hypothesised link between the deep-sea and Antarctic benthic fauna.

The DNA taxonomy of six species of the annelid family Lumbrineridae collected from the Clarion-Clipperton Zone (CCZ) in the Central Pacific, an area of potential mining interest for polymetallic nodules, is presented. Lumbrinerids are an ecologically important and understudied annelid family within the deep sea, with many species still undescribed. This study aims to document the taxonomy and biodiversity of the CCZ using specimens collected from the UK-1, OMS, and NORI-D exploration contract areas and Areas of Particular Environmental Interest. Species were identified through a combination of morphological and molecular phylogenetic analysis. We present informal species descriptions associated with voucher specimens, accessible through the Natural History Museum (London) collections, to improve future taxonomic and biodiversity studies of this region. Five taxa in this study had no morphological or genetic matches within the literature and therefore are possibly new to science, but their suboptimal morphological preservation prevented the formalisation of new species. The most abundant taxon Lumbrinerides cf. laubieri (NHM_0020) was compared with the holotype of Lumbrinerides laubieri Miura, 1980 from the deep Northeast Atlantic. Currently no reliable morphological characters separating the Pacific and Atlantic specimens have been found and molecular data from the Atlantic specimens was not available.

Extractive activities in the ocean are expanding into the vast, poorly studied deep sea, with the consequence that environmental management decisions must be made for data-poor seafloor regions. Habitat classification can support marine spatial planning and inform decision-making processes in such areas. We present a regional, top–down, broad-scale, seafloor-habitat classification for the Clarion-Clipperton Fracture Zone (CCZ), an area targeted for future polymetallic nodule mining in abyssal waters in the equatorial Pacific Ocean. Our classification uses non-hierarchical, k-medoids clustering to combine environmental correlates of faunal distributions in the region. The classification uses topographic variables, particulate organic carbon flux to the seafloor, and is the first to use nodule abundance as a habitat variable. Twenty-four habitat classes are identified, with large expanses of abyssal plain and smaller classes with varying topography, food supply, and substrata. We then assess habitat representativity of the current network of protected areas (called Areas of Particular Environmental Interest) in the CCZ. Several habitat classes with high nodule abundance are common in mining exploration claims, but currently receive little to no protection in APEIs. There are several large unmanaged areas containing high nodule abundance on the periphery of the CCZ, as well as smaller unmanaged areas within the central CCZ, that could be considered for protection from mining to improve habitat representativity and safeguard regional biodiversity.

Future mining of polymetallic nodules in the Clarion Clipperton Fracture Zone (Northeastern Pacific) is expected to affect all benthic ecosystems. The diversity, distribution, and environmental functions of microorganisms inhabiting abyssal sediments are barely understood. To understand the ​consequences of deep-sea mining, experimental in vitro systems needs to be established to test hypotheses on the environmental impact of mining. For this, 40 bacterial strains, belonging to proteobacteria, actinobacteria and firmicutes were isolated from deep-sea sediments and nodules sampled at depths of  4000 m. Phenotypic characterization revealed a strong inter-species and moderate intra-species variability. Determination of minimum inhibitory concentrations indicated the presence of acute manganese-resistant bacteria such as Rhodococcus erythropolis [228.9 mM], Loktanella cinnabarina [57.2 mM], and Dietzia maris [14.3 mM] that might be suitable systems for testing the effects of release of microbes from nodules and their interactions with sediment particles in plumes generated during mining. Comparative genomic analysis indicated the presence of manganese efflux systems relevant for future transcriptomics or proteomics approaches with environmental samples and might serves in paving the way to develop model systems including representative organisms which are currently not cultivable. Monitoring deep-sea mining activity at abyssal depth is a challenge that has to be tackled. We proposed the use of API strips as a fast-on-board methodology for bacterial monitoring as an indicator for sediment plume dispersions within the water column.