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ABSTRACT AimTest the response of mesopelagic zooplankton community composition and distributional ranges to dispersal potential and environment, in comparison with the epipelagic zooplankton community. LocationEpipelagic (0–200 m) and mesopelagic (200–1000 m) depth zones of the North Pacific Ocean. TaxonMulticellular zooplankton. MethodsMetabarcoding of two molecular markers (18S and COI) in combination with a global ocean circulation model, analysed by General Dissimilarity Modelling. ResultsWe found no significant difference in beta‐diversity across three depth strata (0–200, 200–500, and 500–1000 m), calculated from the nMDS dispersion of samples within each stratum. Similarity in beta‐diversity within the three depth strata indicates that epipelagic and mesopelagic zooplankton communities have similar levels of spatial turnover in species composition despite differences in the magnitude of environmental gradients and dispersal potential. There were no differences in the biogeographic ranges of taxa associated with each depth zone, but we observed larger temperature, salinity, and dissolved oxygen habitat envelopes as well as narrower potential food ranges for deeper‐dwelling taxa. Ocean basin‐scale community dissimilarity was correlated with dispersal distance, as well as with changes in temperature, salinity, dissolved oxygen concentration, and food flux. Combined Generalised Dissimilarity Models incorporating both dispersal potential and environmental habitat variables revealed that the environmental variables temperature and food flux had the strongest predictive power to explain community dissimilarity. 

Abstract Wastewater treatment, particularly for persistent organic pollutants (POPs), remains a significant challenge. Although advanced oxidation processes (AOPs) currently used for treating POPs can achieve a decent efficiency, they often involve high costs and necessitate additional post‐treatment processes. Here, a jellyfish‐mimicking, multi‐functional living material encapsulating algae cells are presented, namely Algelly, created using a multi‐material digital‐light processing (DLP) bioprinting technique. The Algelly construct comprises a methacrylated alginate (AlgMA) layer designed to support algae growth, and a poly(N‐isopropylacrylamide) (PNIPAM) layer embedded with magnetic nanoparticles (MNs). The MNs enable the Algelly to respond to near‐infrared (NIR) laser for deformation and magnetic force for steering. It is demonstrated that the DLP bioprinting technique can fabricate the heterogeneous Algelly with high spatial resolution and efficiency, which supports subsequent algae proliferation and effective photosynthesis in the Algelly matrix. Moreover, the NIR‐induced thermo‐responsive deformation and magnetic steering capabilities enhance Algelly's adaptability for recycling and collection. Most importantly, Algelly demonstrates a high efficiency in degrading POPs under white light illumination. Therefore, it is believed that Algelly holds a promising potential for new applications in wastewater treatment, given its efficiency in POP decomposition and flexible location control capabilities. 

ABSTRACT AimWe tested whether co‐distributed phrynosomatid lizards in the Baja California Peninsula (BCP) share synchronous phylogeographic discontinuities, as predicted by the “peninsular archipelago” hypothesis, and examined the diversification ofCallisaurus draconoidesthroughout its range. LocationThe BCP and the Great Basin, Mojave and Sonoran Deserts of southwestern North America. TaxaFive co‐distributed species complexes representing four genera within Phrynosomatidae:Callisaurus,Petrosaurus,UrosaurusandSceloporus. MethodsDouble‐digest restriction‐associated‐DNA (ddRAD) sequencing was used to collect genome‐wide sequence data for 309 lizards. We used phylogenetic analyses of concatenated loci and population admixture analysis of unlinked SNPs to identify lineages. To infer a species tree, we collected target sequence capture (TSC) data. Migration between adjacent peninsular lineages was estimated using the multispecies coalescent with migration (MSC‐M) in BPP. A full‐likelihood Bayesian comparative phylogeographic approach (ecoevolity) was used to test the simultaneous divergence hypothesis for the Isthmus of La Paz and Vizcaíno Desert. ResultsWe identified 24 potential lineages within the five co‐distributed complexes. Contact zones between lineages were observed at the Isthmus of La Paz in four of the five complexes, and in all five within the Vizcaíno Desert. The time‐calibrated species tree indicates that within each complex, divergences at the Isthmus of La Paz predate those across the Vizcaíno Desert. We found strong support for at least three independent divergence events at the Isthmus of La Paz and the Vizcaíno Desert, thereby rejecting the simultaneous divergence hypothesis. Inferred migration rates between adjacent peninsular populations were generally low (M << 1) to absent. Zebra‐tailed lizards (Callisaurus), in which the earliest diverging lineages are endemic to the southern BCP, exhibit a clear pattern of Pleistocene range expansion from the BCP into the deserts of the western United States and mainland Mexico. The most deeply nested populations inCallisaurusoccur at the northern, eastern and southeastern range limits in temperate, subtropical and tropical biomes, respectively. Main ConclusionsThese results support the BCP's tectonic isolation as a driver of peninsular endemism and a contributing factor to lineage diversification more broadly in the region. Taxonomic adjustments, including resurrectingUrosaurus microscutatus, are proposed to better reflect evolutionary history in taxonomy. 

In the binder jetting (BJ) process, as in most of powder bed additive manufacturing technologies, the powder is periodically recoated onto the substrate layer-by-layer. The elements of the current deposited layer corresponding to the part being manufactured are bonded together using a polymeric binder. In all cases that require a thermal process for sintering, the internal structure of the finished part is defined by the internal structure of the powder bed. This article focuses on the discrete element modelling (DEM) of various powder spreading methods during recoating and their impact on the powder bed structure particularly applied to binder jetting technology. The article demonstrates that despite the thinness of the deposited layers, they typically exhibit porosity and particle and pore size non-uniformities along the build-up direction. These irregularities contribute to the anisotropic sintering shrinkage observed in green BJ bodies during experiments. However, the experiments presented confirmed by modelling show that without binder deposition, the powder bed – except for a narrow surface layer – remains relatively uniform, regardless of the recoating method used. It is the binder injection into the porous structure of the powder bed that disrupts this homogeneity, locks in large surface pores, and exacerbates the effects of powder segregation during spreading. Finally, several strategies, explored via simulation, are proposed to reduce porosity variations during BJ: using a combined roller-wide blade method for powder spreading and a two-hopper approach, where each layer consists of small particles deposited over larger ones. 

Abstract Illegal trade in sharks and rays continues to undermine global conservation efforts, with enforcement often hampered by the inability to identify products to the species level. Here, we present a portable, cost-effective High-Resolution melt (HRM) assay for rapid DNA-based identification of elasmobranch species in trade. Using a reference library of 669 vouchered tissue samples collected from field operations and international market surveys, we validated the assay’s capacity to accurately differentiate at least 55 shark and ray species based on melt curve profiles, including 38 species listed under the Convention on International Trade in Endangered Species of Wild Fauna and Flora. Automated image classification enabled high-throughput identification with 99.2% accuracy. The assay yields results within two hours at a per-sample cost of $1.50, and is compatible with portable qPCR platforms, making it suitable for on-site applications. This approach represents a scalable molecular enforcement tool that can empower local authorities to monitor trade more effectively, support compliance with international regulations, and enhance global efforts to combat wildlife trafficking. 

Abstract We present analytical results for the distribution of first return (FR) times of non-backtracking random walks (NBWs) on undirected configuration model networks consisting of $$N$$ nodes with degree distribution $P(k)$. We focus on the case in which the network consists of a single connected component. Starting from a random initial node $$i$$ at time $t=0$, an NBW hops into a random neighbor of $$i$$ at time $t=1$ and at each subsequent step it continues to hop into a random neighbor of its current node, excluding the previous node. We calculate the tail distribution $$P ( T_{\rm FR} > t )$$ of first return times from a random initial node to itself. It is found that $$P ( T_{\rm FR} > t )$$ is given by a discrete Laplace transform of the degree distribution $P(k)$. This result exemplifies the relation between structural properties of a network, captured by the degree distribution, and properties of dynamical processes taking place on the network. Using the tail-sum formula, we calculate the mean first return time $${\mathbb E}[ T_{\rm FR} ]$$. Surprisingly, $${\mathbb E}[ T_{\rm FR} ]$$ coincides with the result obtained from Kac's lemma that applies to simple random walks (RWs). We also calculate the variance $${\rm Var}(T_{\rm FR})$$, which accounts for the variability of first return times between different NBW trajectories. We apply this formalism to Erd{\H o}s-R\'enyi networks, random regular graphs and configuration model networks with exponential and power-law degree distributions and obtain closed-form expressions for $$P( T_{\rm FR} > t )$$ as well as its mean and variance. These results provide useful insight on the advantages of NBWs over simple RWs in network exploration, sampling and search processes. 

Abstract Rising groundwater tables due to sea level rise (SLR) pose a critical but understudied threat to low‐lying coastal regions. This study uses field observations and dynamic modeling to investigate drivers of groundwater variability and to project flooding risks from emergent groundwater in Imperial Beach, California. Hourly groundwater table data from four monitoring wells (2021–2024) reveal distinct aquifer behaviors across soil types. In transmissive coastal sandy soils, groundwater levels are dominated by ocean tides, with secondary contributions from non‐tidal sea level variability and seasonal recharge. In this setting, we calibrated an empirical groundwater model to observations, and forced the model with regional SLR scenarios. We project that groundwater emergence along the low‐lying coastal road will begin by the 2060s under intermediate SLR trajectories, and escalate to near‐daily flooding by 2100. Over 20% of San Diego County's coastline shares similar transmissive sandy geology and thus similar flooding risk. Results underscore the urgency of integrating groundwater hazards into coastal resilience planning, as current adaptation strategies in Imperial Beach—focused on surface flooding—are insufficient to address infrastructure vulnerabilities from below. This study provides a transferable framework for assessing groundwater‐driven flooding in transmissive coastal aquifers, where SLR‐induced groundwater rise threatens critical infrastructure decades before permanent inundation.