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GPR56, an orphan G protein-coupled receptor (GPCR) from the family of adhesion GPCRs, plays an indispensable role in cortical development and lamination. Mutations in the GPR56 gene cause a malformed cerebral cortex in both humans and mice that resembles cobblestone lissencephaly, which is characterized by overmigration of neurons beyond the pial basement membrane. However, the molecular mechanisms through which GPR56 regulates cortical development remain elusive due to the unknown status of its ligand. Here we identify collagen, type III, alpha-1 (gene symbol Col3a1) as the ligand of GPR56 through an in vitro biotinylation/proteomics approach. Further studies demonstrated that Col3a1 null mutant mice exhibit overmigration of neurons beyond the pial basement membrane and a cobblestone-like cortical malformation similar to the phenotype seen in Gpr56 null mutant mice. Functional studies suggest that the interaction of collagen III with its receptor GPR56 inhibits neural migration in vitro. As for intracellular signaling, GPR56 couples to the Gα₁₂/₁₃ family of G proteins and activates RhoA pathway upon ligand binding. Thus, collagen III regulates the proper lamination of the cerebral cortex by acting as the major ligand of GPR56 in the developing brain.

Constraining past West Antarctic Ice Sheet (WAIS) change helps validate numerical models simulating future ice sheet dynamics. Following rapid deglaciation during the mid‐Holocene, ice near Thwaites Glacier was ∼35 m thinner than present; however, the timing of ice regrowth to its present configuration remains unknown. To fill this knowledge gap, we present cosmogenic nuclide exposure ages of cobbles from the surface of a moraine situated between Thwaites and Pope glaciers. We infer that the moraine formed and stabilized in the Late Holocene (∼1.4 ka) when a small glacier thickened. We also present a novel reconstruction of WAIS volume constrained by sea‐level data, which demonstrates that moraine formation coincided with a large‐scale WAIS readvance. Our new geologic constraints will help inform models of the solid Earth response to surface mass loading, improving our understanding of ice sheet dynamics in a vulnerable part of WAIS. Plain Language Summary The Antarctic ice sheets are melting and adding to sea‐level rise, with the rate at which they lose mass expected to increase in the coming decades to centuries. However, recent studies have shown that, only a few thousand years ago, the Antarctic ice sheets were smaller than they are now, and subsequently regrew to their present size. Understanding how the Antarctic ice sheets regrew to their present size, as well as the rate it happened, helps us understand whether ongoing loss of ice sheet mass is reversible. In this study, we identify a glacial landform (a moraine) that was deposited as an Antarctic glacier grew in size after the Antarctic ice sheets were smaller than they are today. We collected rocks from the surface of the glacial landform and measured isotopes in them. These isotopes tell us the landform was created by the glacier about 1,400 years ago. The new information from this study on the past of the Antarctic ice sheets can be used to improve our understanding of how the Antarctic ice sheets will change, and add to sea‐level rise, in the future. Key Points Direct evidence is found for a Late Holocene episode of glacier thickening in the Amundsen Sea Embayment, West Antarctica Ice thickening is evidenced by a moraine between Thwaites and Pope glaciers and is dated with surface exposure dating of erratic cobbles The moraine may help to constrain the end of a mid‐Holocene contracted ice sheet configuration in the Amundsen Sea sector

Generally, in the traditional architecture of Canada and the United States, wood has been used as the main and almost exclusive material for the construction of the buildings of early settlers as it was abundant in the area. Thus, log cabins or wooden frame houses and cottages have become the chief representatives of traditional Canadian and North American architecture. However, wood was expensive or not always at hand in some parts of both countries, so that other materials such as earth, stone, and lime or gypsum were used by the new settlers to build the first constructions. Consequently, different constructive techniques associated with these materials are found in their traditional architecture, some even imported from Europe, with specific links to the individual places of origin of those who built the buildings. This paper aims to provide an initial overview and classification of the use of other materials and other constructive techniques which are also characteristic of a part of traditional architecture common to both Canada and the North of the United States: It also offers an exploration of different specific individual examples including stovewood constructions, sod houses (soddies), and cobblestone structures.

On the sunny Sunday morning of 28 April 2024, SAICE, represented by Keith Mackie of the History and Heritage Panel and Marine Division, conferred the 2024 SAICE National Historic Civil Engineering Landmark status on the Robinson Dry Dock in Cape Town. The event was held as part of the opening celebration of the 35th Permanent International Association of Navigation Congresses (PIANC) Congress, the first in Cape Town and the first in Africa since Alexandria, Egypt in 1926, and was attended by many international conference attendees as well as representatives of Transnet National Ports Authority.

The global spread of non-native species is leading to an increasing frequency of multiple co-occurring non-native species. We examined the co-occurrence of the bivalve mollusc Dreissena polymorpha (zebra mussel) with three Ponto-Caspian amphipods ( Dikerogammarus villosus , Dikerogammarus haemobaphes , and Chelicorophium curvispinum ) across England and Wales in association with in-situ substrate size. For all three amphipod species, substrate grain size where amphipods co-occurred with D. polymorpha was significantly finer than when recorded in isolation. Subsequently, we confirmed this via aquarium experiments. We examined the occurrence of D. villosus with D. polymorpha when present with cobbles, gravel, or sand from three population sources (co-location with abundant D. polymorpha populations, co-location with low populations, and naïve). Experiments demonstrated that D. villosus actively sought shelter on or near D. polymorpha, with their co-location being significantly more prevalent in finer grained substrates (sand > gravel > cobble). The strength of this co-location differed by population source, with those co-located with high D. polymorpha densities demonstrating a greater association. Our analyses and experiments indicate that D. polymorpha may facilitate Ponto-Caspian amphipod establishment in otherwise suboptimal locations, whereby mussel shells provide favourable structural habitat for the amphipods, analogous to the presence of coarse-grained benthic sediment.

Characterizing dispersal traits can further our ecological understanding of Neotropical stream macroinvertebrate communities, allowing us to test fundamental questions about disturbance and functional diversity responses in these systems. We combine observational and experimental approaches to measure short-term colonization of cobbles by stream invertebrates at five headwater streams arrayed along a habitat stability gradient in the Ecuadorian Andes, along with conducting drift and benthic surveys along the same gradient. Cobbles were sampled for benthic macroinvertebrate community composition and basal resource accrual at five time points over the 23-day experimental period. We found that taxonomic richness did not show clear trends across colonization time. Invertebrate community composition in the cobble colonization experiment did not approach the background benthic and drift composition over colonization time. Focal taxa showed variation in their drift and colonization propensities, with no clear relationship to habitat stability. We also found that benthic communities from less stable streams differed greatly between experimental years, highlighting the need to account for intra- and interannual differences in colonization experiments.

Kelp forests are being degraded and/or lost in many regions, and as such, interest in active kelp restoration approaches to reinstate forests is growing. ‘Green gravel’ is a promising new kelp restoration technique that involves seeding small rocks with kelp zoospores, rearing the gametophyte and juvenile sporophyte stages in aquaria before outplanting them at restoration sites. However, to be considered a viable approach to kelp forest restoration, the efficacy of this technique needs to be assessed across a range of environmental contexts and kelp species. Here, we aimed to understand the utility of green gravel as a kelp restoration technique for wave-exposed intertidal shores. Two substrate types – gravel and cobbles – were seeded with Saccharina latissima, reared in the aquarium and outplanted at two sites along the northeast coast of England. Outplanted rocks were monitored for retention, and the density and length of S. latissima. Juvenile sporophytes persisted on both rock types, although declines in density and variations in length were observed over time. Substrate retention was low, with gravel more likely to be removed from restoration sites compared to cobbles, and all outplanted rocks were lost after eight months. While our initial testing of the green gravel restoration technique on wave-exposed shores was not successful, our results provide important insights for developing/refining the technique and a baseline for comparison for future efforts. However, prior to commencing large-scale kelp restoration in wave-exposed areas using green gravel, further testing of the technique and comparisons with other restoration approaches are needed.

Fossils recovered from Baltoscandian erratic boulders and cobbles, collected on the beach near Orłowo and Oksywie Cliff (the latter for the first time) near Gdynia in northern Poland constitute an interesting lot. Several trilo-bite taxa have been discovered, such as ? sp., ? sp., Chasmopsinae indet., sp. and Proetidae indet. Another group of arthropods represented here is Ostracoda, mostly comprising taxa of the family Beyrichiidae, assigned to the order Palaeocopida. The preservation of all fossils certainly leaves much to be desired. Nevertheless, after preparation it has turned out possible to provide some taxonomic identification and the estimated stratigraphical provenance of the erratics studied. In addition, on the basis of taxonomic composition, palaeoecological and palaeogeo-graphical patterns have been worked out. The present paper ranks amongst the very few recent publications dedicated to erratic fossils from Poland in general and those on arthropods specifically.

We present a method for tracking radio-tagged pebbles and cobbles through subglacial meltwater channels under shallow temperate glaciers. Natural particles tagged with active radio transmitters were injected directly into a large subglacial channel 300 m up-glacier from the terminus of the Glacier d'Otemma, Switzerland. A roving antenna was developed to localise tagged particles planimetrically in subglacial and proglacial channel reaches (350 and 150 m long, respectively) using a probabilistic technique, delivering records of the change in particle location and transport distance over time with uncertainty. The roving antenna had a ±5−15 m planimetric precision, a 75% particle localisation rate and operated at a maximum ice depth of 47 m. Additionally, stationary supraglacial and proglacial antennas continuously monitored the passage of tagged particles through consecutive reaches of the channel, constraining the timing of particle transport events. The proglacial antenna system had a 98.1% detection rate and was operational to 0.89 m water depth during testing. Roving and stationary antenna records were combined to create a transport distance model for each particle, which may be used in conjunction with hydraulic data to investigate the kinematics of particle motion. When applied at scale in future studies, this method may be used to reveal the mechanisms and timescales of coarse sediment export from Alpine glaciers.

A 15-year-old boy presented with pink proliferative plaque over both lips. The child was born to a non-consanguineous couple, at full term, and uneventful antenatal, perinatal history. Examination revealed a cobblestone appearance over tongue with papilliferous projections in both labial mucosa with slate-grey pigmentation. The child had multiple lipomatosis and thyroid swelling. Father had thyroid swelling with multiple epidermoid cysts. A final diagnosis of Cowden syndrome. Genetic analysis could not be performed due to financial constraints. Oral mucosal cobblestone appearance is seen in Darier disease, Cowden’s syndrome, lipoid proteinosis, granulomatous cheilitis, mucosal neuroma, Crohn’s disease, and mucous membrane plasmacytosis. Diffuse oral mucosal melanosis is described in Peutz–Jeghers syndrome, Laugier–Hunziker–Baran syndrome, Cowden syndrome, and Addison’s disease. We report this rare genodermatosis, which presents as oral papillomatosis. Early recognition of Cowden syndrome is crucial, as timely diagnosis enables appropriate cancer surveillance, genetic counseling, and preventive interventions, thereby reducing morbidity and improving long-term outcomes.