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Water and mass transport in distributary channel networks play an important role in nourishing fluvial and coastal wetlands, and are largely determined by the morphological configurations of channel bifurcations. While the morphological equilibrium of a single channel bifurcation has been extensively studied, the equilibrium configurations of channel networks with connecting channels linking the bifurcating branches, that is, the “bifurcation‐connecting channel” units that are commonly found in rivers, deltas and estuaries, remain elusive. In this simple yet representative channel network of the “bifurcation‐connecting channel” unit, we observed through numerical simulations an oscillatory water partitioning under moderate Shields stress and channel aspect ratio, in addition to the steady‐state solutions reported in previous studies. The oscillatory water partitioning indicates a newly discovered periodic solution, which is an emergent behavior under constant boundary conditions. We found that the periodic solution is primarily due to the dynamic interactions between bifurcation instability and water surface slope advantage in the two branches modulated by the reversable discharges through the connecting channel, under moderate Shields stress and channel aspect ratio. In such cases, the developed slope advantage in the subordinate branch can suppress the deepening of the dominant branch and eventually lead to the shifting of the dominant branch. In contrast, the channel network attains a steady‐state solution when the slope advantage or the bifurcation instability is dominant with relatively low and high Shields stress (or channel aspect ratio). Our results improve the understanding on the evolution and restoration of channel networks under increasing human interventions in global deltas. Plain Language Summary In rivers, deltas and estuaries, multiple channels deliver water, sediment and nutrients to the fluvial and coastal wetlands and habitats. Where channels split at so‐called bifurcations, water and sediment are divided depending on the shape of the channel and downstream flow conditions. The equilibrium configurations of a single bifurcation have been extensively explored. Specifically, the bifurcation could lead to symmetrical channels but more often asymmetry occurs, so that one downstream channel expands whilst the other tends to be abandoned. Here we add a connecting channel that cross‐cuts the fork, and explore the equilibrium configurations in such a simple but representative network comprising a bifurcation plus a connecting channel. We found that this network exhibits oscillatory behavior in the division of flow and sediment over the branches and the depth of the branches, but on average remains symmetrical. However, when removing the connecting channel, the bifurcation would shift to an asymmetric configuration. Our results imply that the connecting channel can lead to a dynamic yet overall more uniform mass partitioning in distributary channel networks, which in turn affects critical functions such as wetland ecosystem nourishment. These findings also open up new ways to investigate channel networks where tides are important. Key Points Distinctive periodic and steady‐state solutions exist in the channel network of the “bifurcation‐connecting channel” unit The periodic solution is an emergent behavior with oscillatory water partitioning in the network under constant boundary conditions The periodic solution results from the bifurcation instability modulated by the reversing connecting channel

Rapid invasion of Spartina alterniflora in coastal wetlands throughout the world has attracted much attention. Some field and imagery evidence has shown that the landward invasion of S. alterniflora follows the tidal channel networks as the main pathway. However, the specific patterns and processes of its invasion in salt marshes in relation to tidal channel networks are still unclear. Based on yearly satellite images from 2010 to 2018, we studied the patterning relationship between tidal channel networks and the invasion of S. alterniflora at the south bank of the Yellow River Estuary (SBYRE). At the landscape (watershed and cross-watershed) scale, we analyzed the correlation between proxies of tidal channel network drainage efficiency (unchanneled flow lengths (UFL), overmarsh path length (OPL), and tidal channels density (TCD)) and spatial distribution of S. alterniflora. At the local (channel) scale, we examined the area and number of patches of S. alterniflora in different distance buffer zones outward from the tidal channels. Our results showed that, overall, the invasion of S. alterniflora had a strong association with tidal channel networks. Watershed with higher drainage efficiency (smaller OPL) attained larger S. alterniflora area, and higher-order (third-order and above) channels tended to be the main pathway of S. alterniflora invasion. At the local scale, the total area of S. alterniflora in each distance buffer zones increased with distance within 15 m from the tidal channels, whereas the number of patches decreased with distance as expansion stabilized. Overall, the S. alterniflora area within 30 m from the tidal channels remained approximately 14% of its entire distribution throughout the invasion. The results implicated that early control of S. alterniflora invasion should pay close attention to higher-order tidal channels as the main pathway

The Volta River in West Africa is one of the most regulated rivers influenced by dams in the world, and the regulation has resulted in substantial impacts on the hydrological alteration and morphological evolution of the Volta River Delta. However, comprehensive analyses of the relevant effects are still lacking to date. In this study, inter-annual variations of river discharge and sediment load for pre- and post-Akosombo Dam periods (1936 to 2018) were analyzed through simple regression and Mann–Kendall (MK) trend analysis whereas the intra-annual variations were dictated by the non-uniformity and regulated coefficients. The shoreline changes were further evaluated using Landsat remote sensing images (1972 to 2018) to explore the effects of hydrological alteration on the morphological evolution of the Volta River Delta. Hydrological analyses show that the inter- and intra-annual variations are much higher in the pre-dam period, suggesting the substantial regulation of the Akosombo Dam on the Volta River. The dam regulation has more significant effects on the sediment load delivered to the delta than the river discharge, which decreased by 92.32% and 23.23%, respectively. Morphological analyses show that the progradation-erosion of the Volta River Delta constantly fluctuates within a relatively small range (maximum 0.5%) after the 1970s. The relationship between the variations of the delta area and sediment load implicates that a quasi-equilibrium state may have been established at the Volta River Delta, given the current sediment load. Our findings provide references for the future regulation and restoration of the Volta River Delta.

Estimating the biomass of Phragmites australis (Cav.) Trin. ex Steud., i.e., a common wetland macrophyte, and the associated carbon sequestration capacity has attracted increasing attention. Hanshiqiao Wetland Nature Reserve (HWNR) is a large P. australis wetland in Beijing, China, and provides an ideal case study site for such purpose in an urban setting. In this study, an existing P. australis growth dynamics model was adapted to estimate the plant biomass, which was in turn converted to the associated carbon sequestration capacity in the HWNR throughout a typical year. To account for local differences, the modeling parameters were calibrated against the above-ground biomass (AGB) of P. australis retrieved from hyperspectral images of the study site. We also analyzed the sensitivity of the modeling parameters and the influence of environmental factors, particularly the nutrient availability, on the growth dynamics and carbon sequestration capacity of P. australis. Our results show that the maximum AGB and below-ground biomass (BGB) of P. australis in the HWNR are 2.93 × 103 and 2.49 × 103 g m−2, respectively, which are higher than the reported level from nearby sites with similar latitudes, presumably due to the relatively high nutrient availability and more suitable inundation conditions in the HWNR. The annual carbon sequestration capacity of P. australis in the HWNR was estimated to be 2040.73 gC m−2 yr−1, which was also found to be highly dependent on nutrient availability, with a 50% increase (decrease) in the constant of the nutrient availability KNP, resulting in a 12% increase (23% decrease) in the annual carbon sequestration capacity. This implies that a comprehensive management of urban wetlands that often encounter eutrophication problems to synergize the effects of nutrient control and carbon sequestration is worth considering in future practices.

Background and aim To systematically describe the genotypes and phenotypes of NTHL1 -associated tumour syndrome (NATS) cases reported in the literature. Methods A systematic review of literature across Medline, Embase and Web of Science was carried out by two independent reviewers. Studies reporting individuals with germline biallelic NTHL1 likely pathogenic/pathogenic variants (PVs) were identified and collected for statistical analysis. Results In total, 24 studies reported 77 individuals with germline biallelic NTHL1 PVs (51.9% female) from 54 families with 81.8% (63/77) of cases developing at least one cancer [median age at first cancer diagnosis 47 years; range 19–68 years]. The c.244 C > T, p.(Gln82*) PV occurred in 50/54 (92.6%) probands with 31 of these being homozygous and 19 having this PV in compound heterozygosity with another PV. Colorectal cancer occurred in 39/77; (50.6%), with the median age at diagnosis 50 years; range 31–73 years followed by breast cancer 25/77; (32.5%), with median age at diagnosis 47 years; range 36–68 years. Other phenotypes were central nervous system neoplasia, skin, gynecological, urothelial and hematological cancers. Colonic polyposis (≥ 10 polyps of any histology) was observed in 39/70 (55.7%) cases reported to have colonoscopy. In probands, colorectal cancer was the most common indication for genetic testing (38/54; 70.4%) followed by colorectal and breast cancer (8/54; 14.8%). The presence of COSMIC mutational signature SBS30 in a cancer genome may indicate the presence of biallelic NTHL1 deficiency. Conclusion The prevalence of colorectal-, breast, endometrial cancers and meningiomas in this series highlights the importance of surveillance. Findings of this systematic review should inform guidelines for screening and diagnosis. COSMIC mutational signature 30 may assist in defining the tumour spectrum and assessing the pathogenicity of variants of unknown significance. Prospective studies on cancer development in NATS cases, with broader ascertainment, are recommended to further characterize of the cancer spectrum and penetrance.

As an aggressive invasive salt marsh plant, Spartina alterniflora has been found to invade along tidal channel networks and threaten native salt marsh ecosystems. Previous studies have established patterning correlations between S. alterniflora invasion and tidal channel functions (drainage efficiency). However, a systematic analysis of S. alterniflora invasion in relation to functional and geometric features of tidal channel networks is still lacking. In this study, we extracted tidal channel networks from remote sensing images of the Yellow River Delta, China, and performed numerical experiments to examine S. alterniflora invasion patterns with tidal channel networks with varying drainage efficiency and geometric nuances. An existing vegetation dynamics model was adapted to incorporate hydrochorous seed dispersal and salinity buffer zone as the primary mechanisms of tidal channels to facilitate vegetation colonization and was further coupled with Delft3D. We analyzed the correlation of the simulated S. alterniflora area with a comprehensive set of tidal channel functional and geometric metrics across different spatial scales. Our results confirmed that watersheds with higher drainage efficiency (larger tidal channel density ( TCD ) and geometric efficiency ( GE ), smaller overmarsh path length ( OPL )) attained larger S. alterniflora area. Given a similar drainage efficiency, tidal channel networks with greater geometric mean bifurcation ratio enhanced S. alterniflora invasion. On a local scale, channel order dictated local drainage efficiency (spatially-varying TCD o ) and further influenced S. alterniflora area. The observed patterns were further verified in principle by two real cases in the Yellow River Delta. Finally, in viewing the efficacy of all metrics tested and further considering their computational costs, we proposed a holistic metric framework consisting of global metrics including TCD and geometric mean bifurcation ratio and local metric including spatially-varying TCD o , to assess how tidal channel network mediates S. alterniflora invasion in particular and salt marsh vegetation expansion in general in marsh-channel systems.

In recent decades, the invasion of saltmarsh plant Spartina alterniflora ( S. alterniflora ) over a large part of coastal wetlands in China, including the Yellow River Estuary (YRE) as a regional economic hub and global ecosystem services hotspot, has caused increasing concern because of its serious threats to native ecosystems. During the same period, local authorities have implemented a Water-Sediment Regulation Scheme (WSRS) in the Yellow River for flood mitigation and delta restoration purposes. The altered hydrological regime has resulted in unintended changes to estuarine ecosystem. However, the direct consequence of the WSRS on the expansion of S. alterniflora remains unclear. In this study, quantitative relationship between the inter- and intra-annual expansion patterns of S. alterniflora represented by relevant landscape metrics and indicators that quantify the concurrent variations of river and sediment discharges as the proxy of the WSRS impacts were analysed over the period of Year 2011–2018, and the analyses were performed on the YRE as a whole and on five different zones subdivided based on the invasion sequence. The results showed that there was no significant difference in the inter-annual area variation of S. alterniflora between the years with and without WSRS. Compared with the years without WSRS (2016–2017), the intra-annual (monthly) increment of the various landscape metrics [i.e., NP (number of patches), CA (class area), LPI (largest patch index) and AI (aggregation index] were found to be significantly higher in the initial stage of peak growing season (June-July) than in the mid- and late stages (July-September) in the years with WSRS (2011–2015, 2018) in the subregion located close to the south bank of YRE as the most prominent impact zone. In addition, F (mean flow), Ff (number of high flow pulses), Tf (Julian date of maximum flow) and D (duration of WSRS) were identified as the explanatory variables for the intra-annual vegetation landscape pattern changes, and their relative contributions to resultant changes were also assessed. Our results broaden the understanding of estuarine hydrological disturbance as a potential driver regulating the saltmarsh vegetation, and also have implications for S. alterniflora invasion control at estuaries under changing environment.

Previous studies mostly focus on an individual delta, or deltas at a global scale, to explore dam effects on deltaic hydrological alteration and morphological evolution, while comparative studies on selected similar deltas remain scarce. In this study, we compare the alteration of river discharge and sediment load, as well as the associated deltaic area and shoreline, of two deltas, namely, the Volta River Delta in Ghana and the Yellow River Delta in China, which are subject to similar forcings and mainstem dam influences. The results show that the sediment loads of the Volta River Delta and Yellow River Delta have decreased abruptly and gradually, respectively, to ~10% of the pre-dam level, presumably due to differences in reservoir capacity and upstream dam location. Sediment decline has led to a decrease of the fluvial dominance ratio, which has also been affected by the river mouth location and shoreline orientation. As a consequence, the area of the Volta River Delta has shifted to a new quasi-equilibrium, whereas the Yellow River Delta has kept prograding. This comparative study provides references for understanding the future evolution of similar deltas around the world.

Background Current RNA-seq analysis software for RNA-seq data tends to use similar parameters across different species without considering species-specific differences. However, the suitability and accuracy of these tools may vary when analyzing data from different species, such as humans, animals, plants, fungi, and bacteria. For most laboratory researchers lacking a background in information science, determining how to construct an analysis workflow that meets their specific needs from the array of complex analytical tools available poses a significant challenge. Results By utilizing RNA-seq data from plants, animals, and fungi, it was observed that different analytical tools demonstrate some variations in performance when applied to different species. A comprehensive experiment was conducted specifically for analyzing plant pathogenic fungal data, focusing on differential gene analysis as the ultimate goal. In this study, 288 pipelines using different tools were applied to analyze five fungal RNA-seq datasets, and the performance of their results was evaluated based on simulation. This led to the establishment of a relatively universal and superior fungal RNA-seq analysis pipeline that can serve as a reference, and certain standards for selecting analysis tools were derived for reference. Additionally, we compared various tools for alternative splicing analysis. The results based on simulated data indicated that rMATS remained the optimal choice, although consideration could be given to supplementing with tools such as SpliceWiz. Conclusion The experimental results demonstrate that, in comparison to the default software parameter configurations, the analysis combination results after tuning can provide more accurate biological insights. It is beneficial to carefully select suitable analysis software based on the data, rather than indiscriminately choosing tools, in order to achieve high-quality analysis results more efficiently.