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[Display omitted] KMT2D, a H3K4me1 methyltransferase primarily regulating enhancers, is a leading cause of KABUKI syndrome. This multisystem disorder leads to craniofacial and cognitive abnormalities, possibly through neural crest and neuronal lineages. However, the impacted cell-of-origin and molecular mechanism of KMT2D during the development of KABUKI disease remains unknown. Here we have optimized a brain organoid model to investigate neural crest and neuronal differentiation. To pinpoint KMT2D's enhancer target, we developed a genome-wide cis-regulatory element explorer (GREE) based on single-cell multiomic integration. Single cell RNA-seq revealed that KMT2D -knockout (KO) and patient-derived organoids exhibited neural crest deformities and GABAergic overproduction. Mechanistically, GREE identified that KMT2D targets a roof-plate-like niche cell and activates the niche cell-specific WNT3A enhancer, providing the microenvironment for neural crest and neuronal development. Interestingly, KMT2D -mutated mice displayed decreased WNT3A expression in the diencephalon roof plate, indicating impaired niche cell function. Deleting the WNT3A enhancer in the organoids presented phenotypic similarities to KMT2D -depletion, emphasizing the WNT3A enhancer as the predominant target of KMT2D. Conversely, reactivating WNT signaling in KMT2D -KO rescued the lineage defects by restoring the microenvironment. Overall, our discovery of KMT2D's primary target provides insights for reconciling complex phenotypes of KABUKI syndrome and establishes a new paradigm for dissecting the mechanisms of genetic disorders from genotype to phenotype. [ABSTRACT FROM AUTHOR]

ABSTRACT Antarctic krill (Euphausia superba; krill) and the pelagic tunicate (Salpa thompsoni; salps) are crucial to the Southern Ocean ecosystem, and krill supports the largest fishery in the Southern Ocean in term of catch. Given recent climatic changes in the northern Antarctic Peninsula (NAP), the distribution of krill and salps are shifting poleward. Unlike krill, salps thrive in warmer water temperatures and can form large blooms under favorable conditions, potentially outcompeting krill for resources. However, krill are ecologically more important, serving as a primary food source for higher trophic levels. The interspecific interactions, including hotspots and ecological niches, of krill and salps in the NAP were therefore investigated using historical datasets and species distribution models. We found that both spatial separation and overlap occurred between krill and salps hotspots, with the primary overlap occurring around Elephant Island. Furthermore, there was a significant overlap in their ecological niches, suggesting that they may have similar ecological requirements. This study emphasized the importance of krill and salps interactions in the Southern Ocean ecosystem. The krill habitat and therefore food web of the Southern Ocean could be influenced significantly if salps continue to shift poleward in the future. The information provided in this study aids in the conservation and management of the Southern Ocean ecosystem. [ABSTRACT FROM AUTHOR]

The increasing online availability of biodiversity data and advances in ecological modeling have led to a proliferation of open‐source modeling tools. In particular, R packages for species distribution modeling continue to multiply without guidance on how they can be employed together, resulting in high fidelity of researchers to one or several packages. Here, we assess the wide variety of software for species distribution models (SDMs) and highlight how packages can work together to diversify and expand analyses in each step of a modeling workflow. We also introduce the new R package ‘sdmverse' to catalog metadata for packages, cluster them based on their methodological functions, and visualize their relationships. To demonstrate how pluralism of software use helps improve SDM workflows, we provide three extensive and fully documented analyses that utilize tools for modeling and visualization from multiple packages, then score these tutorials according to recent methodological standards. We end by identifying gaps in the capabilities of current tools and highlighting outstanding challenges in the development of software for SDMs. [ABSTRACT FROM AUTHOR]

Telomeres are pivotal determinants of cell stemness, organismal aging, and lifespan. Herein, we examined similarities in telomeres of Arabidopsis thaliana, mice, and humans. We report the common traits, which include their composition in multimers of TTAGGG sequences and their protection by specialized proteins. Moreover, given the link between telomeres, on the one hand, and cell proliferation and stemness on the other, we discuss the counterintuitive convergence between plants and mammals in this regard, focusing on the impact of niches on cell stemness. Finally, we suggest that tackling the study of telomere function and cell stemness by taking into consideration both plants and mammals can aid in the understanding of interconnections and contribute to research focusing on aging and organismal lifespan determinants. [ABSTRACT FROM AUTHOR]

Macrophages are integral components of the innate immune system that colonize organs early in development and persist into adulthood through self-renewal. Their fate, whether they are replaced by monocytes or retain their embryonic origin, depends on tissue type and integrity. Macrophages are influenced by their environment, a phenomenon referred to as developmental programming. This influence extends beyond the local tissue microenvironment and includes soluble factors that can reach the macrophage niche. These factors include metabolites, antibodies, growth factors, and cytokines, which may originate from maternal diet, lifestyle, infections, or other developmental triggers and perturbations. These influences can alter macrophage transcriptional, epigenetic, and metabolic profiles, affecting cell-cell communication and tissue integrity. In addition to their crucial role in tissue immunity, macrophages play vital roles in tissue development and homeostasis. Consequently, developmental programming of these long-lived cells can modulate tissue physiology and pathology throughout life. In this review, we discuss the ontogeny of macrophages, the necessity of developmental programming by the niche for macrophage identity and function, and how developmental perturbations can affect the programming of macrophages and their subtissular niches, thereby influencing disease onset and progression in adulthood. Understanding these effects can inform targeted interventions or preventive strategies against diseases. Finally, understanding the consequences of developmental programming will shed light on how maternal health and disease may impact the well-being of future generations. [ABSTRACT FROM AUTHOR]

Novel introductions of largemouth bass, Micropterus salmoides, often cause negative impacts on endemic populations of prey fishes and interspecific competitors. Although many studies have investigated trophic interactions between M. salmoides and smallmouth bass, Micropterus dolomieu, few have included chain pickerel, Esox niger, as a competitor despite similarities in their habitat use. We used stable isotope analysis to investigate the trophic ecology of a recently introduced population of M. salmoides in the Wolastoq|Saint John River. Specifically, we measured carbon (δ13C) and nitrogen (δ15N) isotopes to describe isotopic niches and infer resource use of introduced M. salmoides, M. dolomieu, E. niger, and native yellow perch, Perca flavescens, at various life stages. Our results showed that isotopic niche overlap occurred between M. salmoides and other study species, indicative of resource competition. However, resource use plasticity, as demonstrated by a wide variety of resources (marine, terrestrial, littoral, and pelagic) used by all study species, could potentially reduce interspecific competition. Our findings indicate that competition is highest between adult M. salmoides and E. niger, but the presence of a seasonal marine resource can provide important contributions to diets and potentially reduce competition. Further research should focus on monitoring of long‐term trends to identify the dynamics of all study species as M. salmoides populations become further established and dispersed. [ABSTRACT FROM AUTHOR]

Shifts in resource use in response to interspecific competition were thought to be necessary for the stable coexistence of consumers sharing the same resources. However, if superiority between competitors switches during development, they may achieve similar lifetime fitness without changing resource use. We tested this hypothesis by allowing two parasitoid wasp species, Pachycrepoideus vindemiae Rondani (Hymenoptera: Pteromalidae) and Trichopria drosophilae Perkins (Hymenoptera: Diapriidae), to exploit large and small Drosophila melanogaster Meigen (Diptera: Drosophilidae) pupae separately or simultaneously to examine whether they change their host preferences in response to interspecific competition. The results showed that both parasitoid species preferred large over small hosts regardless of the presence of competitors, although immature T. drosophilae generally shows a higher mortality rate than P. vindemiae when they shared the same host pupae. This could be explained by the higher fitness loss of T. drosophilae in small hosts, as body size, longevity, and fecundity of T. drosophilae offspring suffered more from a decrease in host size than P. vindemiae. In contrast, adult female T. drosophilae laid more eggs than P. vindemiae, which enabled them to outperform P. vindemiae during host exploration. Consequently, the two parasitoid species had similar numbers of offspring when they were allowed to exploit the host pupae simultaneously. This study provides insights into our understanding of how competing parasitoid species may coexist on the same resources. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Taxa Methods Results Main Conclusions Ecologically similar species living in sympatry are expected to segregate to reduce the effects of competition where resources are limiting. Segregation from heterospecifics commonly occurs in space, but it is often unknown whether such segregation has underlying environmental causes. Indeed, species could segregate because of different fundamental environmental requirements (i.e., ‘niche divergence’), because competitive exclusion at sympatric sites can force species to either change the habitat use they would have at allopatric sites (i.e., ‘niche displacement’) or to avoid certain areas, independently of habitat (i.e., ‘spatial avoidance’). Testing these hypotheses requires the comparison between sympatric and allopatric sites. Understanding the competitive mechanisms that underlie patterns of spatial segregation could improve predictions of species responses to environmental change, as competition might exacerbate the effects of environmental change.North Atlantic and Arctic.Common guillemots Uria aalge and Brünnich's guillemots Uria lomvia.Here, we examine support for these explanations for spatial segregation in two closely‐related seabird species, common guillemots (Uria aalge) and Brünnich's guillemots (U. lomvia). For this, we collated a pan‐Atlantic data set of breeding season foraging tracks from 1046 individuals, collected from 20 colonies (8 sympatric and 12 allopatric). These were analysed with habitat models in a spatially transferable framework to compare habitat preferences between species at sympatric and allopatric sites.We found no effect of the distribution of heterospecifics on local habitat preferences of the focal species. We found differences in habitat preferences between species, but these were not sufficient to explain the observed levels of spatial segregation at sympatric sites.Assuming we did not omit any relevant environmental variables, these results suggest a mix of niche divergence and spatial avoidance produces the observed patterns of spatial segregation. [ABSTRACT FROM AUTHOR]

Aim Methods Results Conclusion The increasing incidence of cesarean sections has led to a higher prevalence of cesarean scar defects (CSDs), predominantly characterized by postmenstrual bleeding in affected women. CSD manifests in various forms, including isolated myometrial defects, intrauterine cystic protrusions, and extrauterine cystic extensions. The pathophysiological mechanisms underpinning CSD and its associated symptoms remain insufficiently understood. This review explores the pathogenesis of CSD, highlights its morphological characteristics with an emphasis on variable clinical diversity, and addresses the challenges for future research.A comprehensive narrative review was conducted using electronic databases, including PubMed and Google Scholar, to identify 41 relevant literatures published up to December 31, 2023.The myometrium comprises two distinct layers—the inner and outer myometrium—with differences in their origin, structure, and function. Disruptions within these layers contribute to CSD development. Histopathologically, symptomatic CSD may be linked to uterine scar endometriosis, cystic adenomyosis, or endometrial cysts, suggesting that CSD, particularly those necessitating surgical intervention, are not limited to myometrial defects but may also involve iatrogenic endometriosis or adenomyosis, thereby exacerbating clinical symptoms.This review provides an updated understanding of the histopathological features and classification of CSD, with an emphasis on elucidating its underlying pathogenesis. [ABSTRACT FROM AUTHOR]

Reef ecosystems are characterized by highly heterogenous habitats and functionally diverse fish communities. Few studies have examined how functional diversity differs among habitats within these communities, i.e., species associated with a specific habitat may have similar trophic ecologies meaning that the functional diversity within the community is driven by habitat diversity or, conversely, high functional diversity within each habitat would indicate that resource segregation also occurs at the habitat level. We used stable isotope ratios of carbon and nitrogen to estimate trophic position, resource use and ontogenetic niche shifts of 15 reef fishes associated with four distinct habitat types (cryptobenthic, epibenthic sand, epibenthic rock and hyperbenthic) on the Croatian coast of the Adriatic Sea. Trophic ecology was quite similar across fish assemblages, but there was strong evidence of niche segregation among fish species within each assemblage showing high functional diversity within each microhabitat. The sampled fish community contained benthic and pelagic resource users, along with multiple intermediate generalists. Consumer stable isotope ratios revealed considerable interspecific variation in resource use among fishes within each habitat type. The cryptobenthic fishes were a notable exception to this trend with the narrow range of resource use values, indicating reliance of these species on a single resource. The greatest diversity of trophic positions within a guild was observed in cryptobenthic and rock‐associated epibenthic fishes. The majority of observed ontogenetic variation in studied fish species reflected an increase in benthic resource use and trophic position. However, the degree of ontogenetic variation in trophic ecology of studied species, if present, was generally low, showing no dramatic change in the ecology of any species. The size structuring among guilds was considerable, with cryptobenthic fishes the smallest on average and hyperbenthic fishes the largest, despite guilds having similar ranges of trophic positions. [ABSTRACT FROM AUTHOR]

In developed cities, bird communities are typically comprised of a few dominant invasive species that can cause considerable social and economic costs. While various studies advocate restricting anthropogenic food as a suitable management approach, a significant knowledge gap persists regarding how these species interact and respond to such an intervention. Here, we evaluate whether limiting a shared food resource may affect their abundances similarly and assess whether such limitations influence their niche dynamics.In Singapore, open food centres for people, colloquially known as hawker centres, serve as key food sources for three highly adapted urban birds: feral pigeons, Javan mynas and house crows. We counted these three species across 63 hawker centres and analysed their niche dynamics across different phases—before, during COVID‐19 social restrictions when dining‐in was prohibited, and during an enforcement phase mandating the return of crockery. We modelled their counts, diet niche widths and niche overlaps, considering predictors which include the sampling phases, food availability, structural characteristics of hawker centres and spatial attributes such as distance to public housing.During social restrictions, feral pigeon and Javan myna counts showed a significant decline, while the count proportions of the three species compared to each other remained relatively stable. Hawker centres closer to bridges and public housing, and those that structurally more open, attracted more birds.The niche widths of feral pigeons and Javan mynas significantly narrowed during social restrictions due to reduced food availability. However, their niche overlaps remained consistent across sampling phases, indicating resource partitioning strategies to cope with extreme food shortages—feral pigeons adapted by foraging more on grass verges outside, while Javan mynas frequented tray return stations. This resilience in maintaining species proportions and the absence of significant niche overlap suggested the existence of an ecological balance despite substantial reductions in available food.Synthesis and applications. Our study underscores the importance of controlling human‐provided food to collectively manage dominant urban bird commensals. Beyond the two social restriction phases, curbing the availability of anthropogenic food through enforcement also kept nuisance birds away, validating a cost‐effective approach in reducing their counts. [ABSTRACT FROM AUTHOR]

To be effective, a biocontrol agent must survive and persist in the same habitat as the target species and reduce target population growth. When multiple biocontrol agents are used against a single invasive species, they may each perform better under a subset of the habitat in which the target lives. This complementarity allows for a more consistent level of control and a higher resilience to environmental variability. Two species that feed on the same plant tissues would compete, but niche partitioning in the native range may be replicated when both species are introduced to the invasive range. When biocontrol agents are released, they may self‐sort to perform best in their respective niches. We hypothesized that two biocontrol agents—Scotch broom seed beetle, Bruchidius villosus (Fabricius) (Coleoptera: Chrysomelidae) and Scotch broom seed weevil, Exapion fuscirostre (Fabricius) (Coleoptera: Brentidae)—that both feed on seeds of the invasive legume Scotch broom, Cytisus scoparius L. Link (Fabaceae), would be impacted differently by different weather conditions and plant traits, and would show different success rates at field sites with different conditions. We used a 5‐year study to reveal that the two biocontrol agents are not uniformly distributed in the field and that weather and plant factors influence their success. We confirmed that weather conditions of the previous year influenced biocontrol agent attack rate and found that weather patterns at a field site may predict the impact of each biocontrol agent. [ABSTRACT FROM AUTHOR]

Introduction: Plants are inherently connected with the microbiome, which plays a crucial role in regulating various host plant biological processes, including immunity, nutrient acquisition, and resistance against abiotic and biotic stresses. Many factors affect the interaction between plants and microbiome. Methods and results: In this study, microbiome samples were collected from five niches (bulk soil, rhizoplane, root endosphere, phylloplane, and leaf endosphere) across four developmental stages (seedling, flowering, podding, and maturity) of various soybean varieties. Composition and structure of bacterial and fungal communities were analyzed using 16S rRNA gene and ITS (Internally Transcribed Spacer) region amplicon sequencing. It was observed that both niches and developmental stages significantly impact on the assembly and composition of soybean microbiome. However, variety, presence of a transgene, and glyphosate application had minimal effects on microbial communities. The dominant microbiome varied across the five niches, with most containing beneficial microbial communities capable of promoting plant growth or increasing disease resistance. Types and abundance of the dominant microbes affected network stability, potentially resulting in functional changes in different ecological niches. Conclusion: This study provides theoretical evidence for microbial protection of plants against diseases and demonstrates that systematic analysis of the composition and diversity of soybean microbiomes can contribute to the development of biological control technologies. [ABSTRACT FROM AUTHOR]

Understanding the maintenance and shift in reproductive strategies is a fundamental question in evolutionary research. Although many efforts have been made to compare different reproductive strategies, the association between reproductive strategies and lineage divergence is largely unknown. To explore the impact of different reproductive strategies on lineage divergence, we investigated the evolution of clonality in Saxifraga sect. Irregulares+Heterisia. By integrating several lines of evidence, we found that the loss of clonality in Irregulares+Heterisia was associated with a progressive increase in diversification rate and intraspecific morphological diversity but with a reduction in species distribution range. Our findings provide insights into the ecological and evolutionary effects of different reproductive strategies, suggesting the necessity of integrating clonality into ecological and evolutional research. [ABSTRACT FROM AUTHOR]

ABSTRACT The deep‐sea benthos often exhibit exceptional biodiversity. The patch‐mosaic hypothesis proposes that this deep‐sea diversity arises from varied microhabitats with prolonged temporal persistence filtering for distinctive communities thereby increasing beta‐diversity. This study investigated environmental, community, and macrofaunal species turnover at four deep‐sea sites (~2000 m) in the northern Gulf of Mexico. Using precise small‐scale sampling with a ROV, we analyzed patterns across spatial scales from centimeters to approximately 400 km among 67 sediment cores. We examined the relationships between sedimentary carbon, sediment grain size, and macrofaunal alpha‐ and beta‐diversity. Subsequently, we explored the role of these environmental properties and their spatial arrangement in shaping communities and species distributions. We observed a consistent trend where the overall abundance and diversity of a community increased with higher carbon but decreased with increasing grain size. Substantial faunal turnover was observed among cores, even at centimeter scales, with the contribution of centimeter‐scale spatial distance rivaling that of 100‐km scales in faunal dissimilarity. Similar to alpha‐diversity, beta‐diversity exhibited strong correlations with sediment carbon and grain size. The observed random spatial structure in grain size and carbon appear to translate into randomness in both community and species distribution. These findings align with the patch‐mosaic model, underscoring the complexity of deep‐sea ecosystems. These findings suggest an intricate relationship between sedimentary attributes, faunal composition, and spatial arrangement in the deep‐sea benthos, shedding light on the mechanisms driving biodiversity in seemingly homogeneous environments. [ABSTRACT FROM AUTHOR]

Certain immune cells, including neutrophils, macrophages, dendritic cells, B cells, Breg cells, CD4+ T cells, CD8+ T cells, and Treg cells, establish enduring residency within the bone marrow. Their distinctive interactions with hematopoiesis and the bone marrow microenvironment are becoming increasingly recognized alongside their multifaceted immune functions. These cells play a dual role in shaping hematopoiesis. They directly influence the quiescence, self-renewal, and multi-lineage differentiation of hematopoietic stem and progenitor cells through either direct cell-to-cell interactions or the secretion of various factors known for their immunological functions. Additionally, they actively engage with the cellular constituents of the bone marrow niche, particularly mesenchymal stem cells, endothelial cells, osteoblasts, and osteoclasts, to promote their survival and contribute to tissue repair, thereby fostering a supportive environment for hematopoietic stem and progenitor cells. Importantly, these bone marrow immune cells function synergistically, both locally and functionally, rather than in isolation. In summary, immune cells residing in the bone marrow are pivotal components of a sophisticated network of regulating hematopoiesis. [ABSTRACT FROM AUTHOR]

We assessed changes in fundamental climate‐niche space for lizard and snake species in western North America under modeled climate scenarios to inform natural resource managers of possible shifts in species distributions. We generated eight distribution models for each of 130 snake and lizard species in western North America under six time‐by‐climate scenarios. We combined the highest‐performing models per species into a single ensemble model for each scenario. Maps were generated from the ensemble models to depict climate‐niche space for each species and scenario. Patterns of species richness based on climate suitability and niche shifts were calculated from the projections at the scale of the entire study area and individual states and provinces, from Canada to Mexico. Squamate species' climate‐niche space for the recent‐time climate scenario and published known ranges were highly correlated (r = 0.81). Overall, reptile climate‐niche space was projected to move northward in the future. Sixty‐eight percent of species were projected to expand their current climate‐niche space rather than to shift, contract, or remain stable. Only 8.5% of species were projected to lose climate‐niche space in the future, and these species primarily occurred in Mexico and the southwestern U.S. We found few species were projected to lose all suitable climate‐niche space at the state or province level, although species were often predicted to occupy novel areas, such as at higher elevations. Most squamate species were projected to increase their climate‐niche space in future climate scenarios. As climate niches move northward, species are predicted to cross administrative borders, resulting in novel conservation issues for local landowners and natural resource agencies. However, information on species dispersal abilities, landscape connectivity, biophysical tolerances, and habitat suitability is needed to contextualize predictions relative to realized future niche expansions. [ABSTRACT FROM AUTHOR]

Themorphology of cells in vivo can arise from a variety of mechanisms. In the Caenorhabditis elegans hermaphrodite gonad, the distal tip cell (DTC) elaborates into a complex plexus over a relatively short developmental time period, but the mechanisms underlying this change in cell morphology are not well defined. We correlated the time of DTC elaboration with the L4-to-adult molt, but ruled out a relevant heterochronic pathway as a cue for DTCelaboration. Instead, we found that the timing of gonad elongation and aspects of underlying germline flux influence DTC elaboration. We propose a 'hitch and tow' aspect of organ-level dynamics that contributes to cellular morphogenesis, whereby germline flux drags the flexible DTC cell cortex away from its stationary cell body. More broadly, we speculate that this mechanism may contribute to cell shape changes in other contexts with implications for development and disease. [ABSTRACT FROM AUTHOR]

Species distribution information is essential for conservation. However, sampling the full range of a species' potential distribution is rarely feasible, necessitating the development of models to predict distributions, as well as relevant environmental and biotic drivers. We applied a novel approach to model the distribution of a species at risk in Canada, silver shiner (SS; Notropis photogenis) in tributaries of Lake Ontario using the fish community as a predictor of SS occurrence. Associative rule learning (ARL) identified simple species combinations that provided strong insight into SS distribution, which may be particularly useful for identifying new occupied locations, including making sampling decisions in real time. The species with the most positive or negative associations with SS identified by ARL were included in a random forests model, which predicted SS distribution with high accuracy in test data from the study tributary system and in a neighbouring system where SS is exceedingly rare. Predicting species distributions based on biotic associations presents opportunities for discovering new populations, identifying critical habitat, and evaluating the suitability of sites for re-introduction potential. [ABSTRACT FROM AUTHOR]

Neural stem cells (NSCs) persist in the adult mammalian brain and are able to give rise to new neurons and glia throughout life. The largest stem cell niche in the adult mouse brain is the ventricular-subventricular zone (V-SVZ) lining the lateral ventricles. Adult NSCs in the V-SVZ coexist in quiescent and actively proliferating states, and they exhibit a regionalized molecular identity. The importance of such spatial diversity is just emerging, as depending on their position within the niche, adult NSCs give rise to distinct subtypes of olfactory bulb interneurons and different types of glia. However, the functional relevance of stem cell heterogeneity in the V-SVZ is still poorly understood. Here, we put into perspective findings highlighting the importance of adult NSC diversity for brain plasticity, and how the body signals to brain stem cells in different physiological states to regulate their behavior. [ABSTRACT FROM AUTHOR]

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Global mapping of forest height is an extremely important task for estimating habitat quality and modeling biodiversity. Recently, three global canopy height maps have been released, the global forest canopy height map (GFCH), the high‐resolution canopy height model of the Earth (HRCH), and the global map of tree canopy height (GMTCH). Here, we assessed their accuracy and usability for biodiversity modeling. We examined their accuracy by comparing them with the reference canopy height models derived from airborne laser scanning (ALS). Our results show considerable differences between the evaluated maps. The root mean square error ranged between 10 and 18 m for GFCH, 9–11 m for HRCH, and 10–17 m for GMTCH, respectively. GFCH and GMTCH consistently underestimated the height of all canopies regardless of their height, while HRCH tended to overestimate the height of low canopies and underestimate tall canopies. Biodiversity models using predicted global canopy height maps as input data are sufficient for estimating simple relationships between species occurrence and canopy height, but their use leads to a considerable decrease in the discrimination ability of the models and to mischaracterization of species niches where derived indices (e.g., canopy height heterogeneity) are concerned. We showed that canopy height heterogeneity is considerably underestimated in the evaluated global canopy height maps. We urge that for temperate areas rich in ALS data, activities should concentrate on harmonizing ALS canopy height maps rather than relying on modeled global products. [ABSTRACT FROM AUTHOR]

Many methods have been proposed to model the spatial distribution of a species. While some methods have been specifically designed for this purpose, others are well‐known statistical tools that can be used in many scientific fields. In this paper, I propose a new ecological niche model, called the Environmental String Model (ESM), that is based on the concept of environmental string, which is defined as being a combination of environmental variables, with as many nodes as environmental variables. There are two types of environmental strings: (1) the abundance‐known string and (2) the abundance‐unknown string (or target string) for which an estimation of abundance is searched. The novelty of the model is that it assesses the abundance associated with a target string from nearby abundance‐known strings, which preserve the local multidimensional relationships with the target string. The model does not provide an abundance estimate in the absence of data from a similar environment and it can therefore deal with truncated spatial distributions or niches. It is tested in the North Atlantic Ocean on two key copepod species, Calanus finmarchicus and Calanus helgolandicus, which have been monitored by the Continuous Plankton Recorder (CPR) survey for decades. I investigate the influence of variables on model performance. I show that the model reconstructs the mean spatial distribution and seasonal fluctuations in both Calanus well. When compared with generalized linear models (GLMs), generalized additive models (GAMs) and generalized regression neural network (GRNN), the ESM gives the best performance. I propose a number of indicators to evaluate the robustness of estimated abundance in space and time and show how the model may be extended to presence/absence or presence‐only data. I think that the ESM could be used to fill gaps in any sampling program such as the CPR survey and many satellite databases (e.g., ocean color and photosynthetically active radiation). [ABSTRACT FROM AUTHOR]

BACKGROUND: The range of Glires is influenced by human activities and climate change. However, the extent to which human activities and environmental changes have contributed to this relationship remains unclear. We examined alterations in the distribution changes and driving factors of the Himalayan marmot, plateau pika, and plateau zokor on the Qinghai–Tibet Plateau (QTP) using the maximum entropy (MaxEnt) model and a geographical detector (Geodetector). RESULTS: The MaxEnt model showed that the contribution rates of the human footprint index (HFI) to the distribution patterns of the three types of Glires were 46.70%, 58.70%, and 59.50%, respectively. The Geodetector results showed that the distribution pattern of the Himalayan marmot on the QTP was influenced by altitude and the normalized difference vegetation index (NDVI). The distribution patterns for plateau pikas and plateau zokors were driven by HFI and NDVI. Climate has played a substantial role in shaping suitable habitats for these three Glires on the QTP. Their suitable area is expected to decrease over the next 30–50 years, along with their niche breadth and overlap. Future suitable habitats for the three Glires tended to shift toward higher latitudes on the QTP. CONCLUSION: These findings underscore the impacts of environmental and human factors on the distribution of the three Glires on the QTP. They have enhanced our understanding of the intricate relationships between Glires niches and environments. This can aid in identifying necessary interventions for developing effective early warning systems and prevention strategies to mitigate Glires infestations and plague epidemics on the QTP. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Taking the elfin forest community on the top of the mountain in the Mulinzi National Nature Reserve in Hubei as the research object, the ecological niche, interspecific connection characteristics, and community stability of the dominant species in the elfin forest community on the top of the mountain were analyzed, and the resource utilization strategy and survival mechanism of plants in unique habitats were explored. Based on a field survey, the niche width, niche overlap index, variance ratio method, chi-squared test, Spearman's rank correlation test, Pearson's correlation test, and M. Godron stability assay were used to analyze the niche, interspecific connection characteristics, and stable communities of the dominant species in the elfin forest community at the top of Mulinzi Mountain. Quercus glauca had the highest significant value and niche width and was found to be the dominant species in the community. Enkianthus serrulatus, followed by Sorbus caloneura, were the main species in the community, but the order of importance and niche width were significantly different. Among the 190 species pairs comprising 20 dominant species, 21. 05%of the species pair niche overlap index values were more significant than 0. 5, and 50. 00%were between 0. 2 and 0. 5. There is a common phenomenon of niche overlap among populations, and dominant species have a high degree of niche overlap with other populations. The overall association with the community showed an insignificant positive association. The chi-squared test showed that 98. 95%of the species pairs showed an insignificant or no association. Pearson's and Spearman's rank correlation tests also showed no significant association between most species, and the association between various groups was weak. Most species in the elfin forest community at the top of Mulinzi Mountain were loosely connected, and competition with the dominant species for environmental resources was weak. Harsh environmental conditions altered the survival and resource utilization strategies of various species in the community. Community structures have adapted to such habitats, and environmental resources have been utilized more fully. The community is relatively stable. [ABSTRACT FROM AUTHOR]

Ageing and fertility are intertwined. Germline loss extends the lifespan in various organisms, termed gonadal longevity. However, the original longevity signal from the somatic gonad remains poorly understood. Here, we focused on the interaction between germline stem cells (GSCs) and their niche, the distal tip cells (DTCs), to explore the barely known longevity signal from the somatic gonad in C. elegans. We found that removing germline disrupts the cell adhesions between GSC and DTC, causing a significant transcriptomic change in DTC through hmp-2 /β-catenin and two GATA transcription factors, elt-3 and pqm-1 in this niche cell. Inhibiting elt-3 and pqm-1 in DTC suppresses gonadal longevity. Moreover, we further identified the TGF-β ligand, tig-2, as the cytokine from DTC upon the loss of germline, which evokes the downstream gonadal longevity signalling throughout the body. Our findings thus reveal the source of the longevity signalling in response to germline removal, highlighting the stem cell niche as a critical signalling hub in ageing. Synopsis: How loss of the germline increases longevity in C. elegans has remained unknown. This study shows that germline ablation is sensed by adhesion disruption between germline stem cells (GSCs) and gonadal niche cells, altering stromal expression patterns and cytokine secretion for enhanced longevity signalling in distal tissues. Depletion of GSCs disrupts the cell adhesion with their niche, distal tip cells (DTCs), leading to transcriptome changes and enhanced longevity of worms. Translocation of HMP-2/β-catenin, and the GATA transcription factors, ELT-3 and PQM-1, are required for DTC-mediated longevity induction upon germline loss. TGF-β ligand TIG-2 is upregulated and secreted by DTCs upon germline loss, activating systemic longevity signalling pathways. Defective germline stem cell maintenance disrupts niche cell adhesion, altering transcription factor expression and growth factor secretion for increased longevity in the worm. [ABSTRACT FROM AUTHOR]

Environmental factors and interspecific interactions, such as competition and facilitation, can shape species' geographic ranges. Here, we tested the relationship between geographic range overlap of squamate sister species, and their divergence in body size, diel activity, and microhabitat use. Competition theory predicts that sister species with similar traits will overlap less geographically than sister pairs with dissimilar traits. However, similar distributions may present similar selective pressures and favour similar adaptations, such that habitat filtering may result in species with more similar traits in sympatry. Across 1434 sister species contrasts, we found little relationship between range overlap and niche divergence. In some models, the divergence in body size and microhabitat use marginally increased with sympatry, while in other models, sympatric sisters had similar activity times. However, the low R‐squared values of almost all these models lend only weak support to predictions from competition or habitat filtering theories. Sympatric sister species within the same biome showed more similar activity times than expected, lending some support to habitat filtering. Niche divergence in allopatry or sympatry, as calculated using a multi‐trait dissimilarity index, did not show a phylogenetic signal, and niches of sister species from different squamate clades did not deviate significantly from the null expectation. Overall, niche divergence or convergence, across the axes we explored, is not a prerequisite for regional species co‐occurrence. We suggest here that the lack of consistent support for either limiting similarity or habitat filtering may reflect that both these forces act as transient phenomena. More fine‐grained analyses, in space and time, would be needed to detect their fingerprints. Thus, coexistence in the face of competition can arise due to various evolutionary and biogeographic mechanisms, acting concurrently or asynchronously. [ABSTRACT FROM AUTHOR]

Thermo-mineral springs are specific ecosystems with extreme environmental conditions that constitute interesting models for studying metacommunity processes. Since these springs can be considered as islands within a terrestrial context, we first aimed to test some predictions of the theory of island biogeography and the distance-decay hypothesis on benthic diatom communities. Then, we aimed to quantify the influence of physical, chemical, climatic and spatial factors on species assemblages. We evaluated the species-area relationship for all springs and for several group of springs classified according to their environmental and hydrochemical composition. The influence of environmental variables on α-diversity was tested. We also investigated whether β-diversity was related to spring isolation or changes in environmental conditions. Finally, we determined the importance of environmental and spatial variables in shaping diatom communities using ordination and variation partitioning. We did not find any species-area relationship whatever the group of springs investigated, and no geographical distance-decay pattern was observed. We found a significant effect of physical and chemical parameters on α-diversity and composition. Thus, diatoms communities of thermo-mineral springs did not seem to be influenced by dispersal processes at the scale of our study but appeared to be patterned by physical and chemical factors. [ABSTRACT FROM AUTHOR]

Context: Freshwater primary productivity is threatened by the decline in biodiversity associated with nutrient enrichment, but there is still uncertainty about how the biodiversity and productivity relationship (BPR) varies with the trophic states. Aims: We aimed to examine the variation of benthic diatom BPRs in three plateau lakes with different trophic states and their underlying driving mechanisms. Methods: We examined the relationship between diatom taxonomic and functional diversity, niche width, and niche overlap with productivity. Key results: The taxonomic and functional diversity, niche width and productivity of benthic diatoms were highest in the mesotrophic lake. The benthic diatom BPRs were linear and positive, with the slope of BPRs being the lowest in eutrophic lake. Motile, non-attached and small-sized diatoms were dominant in eutrophic lake. Nutrient concentrations indirectly affected primary productivity by influencing algal community structure, niche width and biodiversity change. Conclusions: Diatom productivity and diversity showed a positive relationship, but nutrient enrichment weakened this relationship. By combining taxonomic and functional diversity indices, supplemented by niche analysis, we can further understand the variation of diatom productivity. Implications: The results provide a basis for predicting the changes in BPRs of benthic diatoms in the littoral zone with different trophic states. This study examined the benthic diatom biodiversity–productivity relationship (BPRs) and the underlying mechanisms in high-plateau lakes along trophic states. The BPRs were linear and positive at all trophic levels, but eutrophication may weaken this relationship. Motile, non-attached and small-sized cells contributed notably to reducing the productivity and BPR. Nutrients affected productivity indirectly by influencing algal community structure, niche width and by biodiversity change. [ABSTRACT FROM AUTHOR]

Spermatogonial stem cells (SSCs) play a crucial role in the male reproductive system, responsible for maintaining continuous spermatogenesis. The microenvironment or niche of SSCs is a key factor in regulating their self-renewal, differentiation and spermatogenesis. This microenvironment consists of multiple cell types, extracellular matrix, growth factors, hormones and other molecular signals that interact to form a complex regulatory network. This review aims to provide an overview of the main components of the SSCs microenvironment, explore how they regulate the fate decisions of SSCs, and discuss the potential impact of microenvironmental abnormalities on male reproductive health. [ABSTRACT FROM AUTHOR]

Background: Studying habitat use and vertical movement patterns of individual fish over continuous time and space is innately challenging and has therefore largely remained elusive for a wide range of species. Amongst sharks, this applies particularly to smaller-bodied and less wide-ranging species such as the spurdog (Squalus acanthias Linnaeus, 1758), which, despite its importance for fisheries, has received limited attention in biologging and biotelemetry studies, particularly in the North-East Atlantic. Methods: To investigate seasonal variations in fine-scale niche use and vertical movement patterns in female spurdog, we used archival data from 19 pregnant individuals that were satellite-tagged for up to 365 days in Norwegian fjords. We estimated the realised niche space with kernel densities and performed continuous wavelet analyses to identify dominant periods in vertical movement. Triaxial acceleration data were used to identify burst events and infer activity patterns. Results: Pregnant females frequently utilised shallow depths down to 300 m at temperatures between 8 and 14 °C. Oscillatory vertical moments revealed persistent diel vertical migration (DVM) patterns, with descents at dawn and ascents at dusk. This strict normal DVM behaviour dominated in winter and spring and was associated with higher levels of activity bursts, while in summer and autumn sharks predominantly selected warm waters above the thermocline with only sporadic dive and bursts events. Conclusions: The prevalence of normal DVM behaviour in winter months linked with elevated likely foraging-related activity bursts suggests this movement behaviour to be foraging-driven. With lower number of fast starts exhibited in warm waters during the summer and autumn months, habitat use in this season might be rather driven by behavioural thermoregulation, yet other factors may also play a role. Individual and cohort-related variations indicate a complex interplay of movement behaviour and habitat use with the abiotic and biotic environment. Together with ongoing work investigating fine-scale horizontal movement as well as sex- and age-specific differences, this study provides vital information to direct the spatio-temporal distribution of a newly reopened fishery and contributes to an elevated understanding of the movement ecology of spurdog in the North-East Atlantic and beyond. [ABSTRACT FROM AUTHOR]

Anacolia menziesii sensu lato (Bartramiaceae) is a common and widespread moss in western North America that has been treated as either a single variable species or two distinct taxa, A. menziesii s.s. and A. baueri, with the two variously interpreted as species or subspecies. Interpretation has been hampered historically because the primary character used to separate the two entities, capsule shape, is absent on most specimens of this dioicous moss, and gametophytes have not yielded characters that can be used to separate the two putative entities with confidence. Here, we quantified previously categorical traits to test whether morphological characters are continuous across the geographic range or whether discrete morphological groups exist within A. menziesii s.l. We found that quantitative sporophyte characters replacing analogous categorical characters support the recognition of two entities, and that quantitative gametophyte characters also support the recognition of two entities. Furthermore, the two morphologically defined entities are overlapping geographically but have distinctive ecological niches. This provides strong evidence supporting the recognition of two species and provides new tools for separating sterile material. [ABSTRACT FROM AUTHOR]

Deep‐pelagic fishes are among the most abundant vertebrates on Earth. They play a critical role in sequestering carbon, providing prey for harvestable fishing stocks and linking oceanic layers and trophic levels. However, knowledge of these fishes is scarce and fragmented, hampering the ability of both the scientific community and stakeholders to address them effectively. While modelling approaches incorporating these organisms have advanced, they often oversimplify their functional and ecological diversity, potentially leading to misconceptions. To address these gaps, this synthesis examines the biodiversity and ecology of global deep‐pelagic fishes. We review pelagic ecosystem classifications and propose a new semantic framework for deep‐pelagic fishes. We evaluate different sampling methods, detailing their strengths, limitations and complementarities. We provide an assessment of the world's deep‐pelagic fishes comprising 1554 species, highlighting major groups and discussing regional variability. By describing their morphological, behavioural and ecological diversity, we show that these organisms are far from homogeneous. Building on this, we call for a more realistic approach to the ecology of deep‐pelagic fishes transitioning between very different ecological niches during diel vertical migrations. To facilitate this, we introduce the concept of 'diel‐modulated realised niche' and propose a conceptual model synthesising the multiple drivers responsible for such transitions. [ABSTRACT FROM AUTHOR]

Biological communities are structured by a variety of biotic and abiotic relationships, whose understanding forms the basis for effective conservation. Among the myriad factors influencing community dynamics, resource partitioning stands out, potentially enriching ecosystem complexity but also carrying risks for conservation if disregarded. In this study, we investigated intersexual and ontogenetic niche differences among populations of the West African softshell turtle Trionyx triunguis in Liberia, Cote d'Ivoire, Ghana and Nigeria. We observed that these distinct populations exhibited similar habitat preferences, favouring large rivers with abundant riverbank and aquatic vegetation, and muddy substrates. Disparities in habitat preferences were evident among populations and across various life stages, indicating the adaptability of the species. We found that the species was active throughout the year, but most of our sightings and captures occurred during the wet season. In light of the species' vulnerability to overhunting, our research findings provide important data on the ecology of this species that can assist in its effective conservation across all life stages. [ABSTRACT FROM AUTHOR]

Several studies have investigated the gut bacterial composition of wild ungulates in the Qinghai–Xizang Plateau. However, the relationship between their gut microbiome dendrograms and their phylogenetic tree remains unclear. In this study, we analyzed 45 amplicons (V3–V4 region of the 16S rRNA gene) from five wild ungulates—Pseudois nayaur, Pantholops hodgsonii, Gazella subgutturosa, Bos grunniens, and Equus kiang—from the Qinghai–Xizang Plateau to clarify the relationship between their phylogenies and gut microbiome dendrograms. The unweighted pair group method with arithmetic mean analysis and hierarchical clustering analysis indicated that G. subgutturosa is closely related to P. nayaur; however, these results were inconsistent with their phylogenetic trees. Additionally, the indicator genera in the microbiome of each wild ungulate showed strong associations with the diets and habitats of their host. Thus, diet and space niche differentiation may primarily account for the differences between the gut microbiome characteristics of these wild ungulates and their phylogeny. In summary, our research provides insights into the evolutionary factors influencing the gut microbiome of wild ungulates in the Qinghai–Xizang Plateau. [ABSTRACT FROM AUTHOR]

Past climate changes have had large impacts on modern ecological patterns. Understanding if legacies are distinguishable in the climatic niches of extant and locally extinct taxa can provide insight into the importance of climate in extinction events. To better understand mid‐ to late‐Cenozoic New Zealand plant extinctions, which are often attributed to Cenozoic climate cooling, we identify 13 con‐familial extinct and extant New Zealand genus pairs, which have modern distributions in Australia. Using climatic niches derived from current geographic distributions in Australia, we compared (i) total niche breadth, (ii) niche overlap, and (iii) individual climate parameters, to investigate potential climate drivers of intrafamilial extinction and persistence patterns in New Zealand. A majority of New Zealand extinct genera (9 out of 13 pairs) do not indicate climate niche legacies consistent with susceptibility to extinction from changing climates, while the remaining four extinct/extant pairs show slight climatic niche legacies. Three extinct genera have warmer niches than their extant counterpart, which is consistent with extinction reflecting intolerance of cooling Cenozoic climates. The other genus pair with a climatic niche legacy has an extinct genus that is distinguished by a niche with smaller precipitation seasonality than its extant counterpart, suggesting that climate metrics other than temperature may also be important extinction drivers in some taxa. Our results show that the mechanisms of Cenozoic extinctions of New Zealand genera are likely more complex than taxa reaching environmental tolerances due to cooling climates. Comparisons of current climatic niches between extant and extinct sister taxa can provide useful insights into large‐scale, long‐term climatic legacies but more analyses, including trait and phylogeographic patterns, would lead to additional insights into alternative pathways of extinction. [ABSTRACT FROM AUTHOR]

Early diagnosis and appropriate management of Cesarean scar pregnancy (CSP) are crucial to prevent severe complications, such as uterine rupture, severe hemorrhage and placenta accreta spectrum disorders. In this article, we provide a step‐by‐step tutorial for the standardized sonographic evaluation of CSP in the first trimester. Practical steps for performing a standardized transvaginal ultrasound examination to diagnose CSP are outlined, focusing on criteria and techniques essential for accurate identification and classification. Key sonographic markers, including gestational sac location, cardiac activity, placental implantation and myometrial thickness, are detailed. The evaluation process is presented according to assessment of the uterine scar, differential diagnosis, detailed CSP evaluation and CSP classification. This step‐by‐step tutorial emphasizes the importance of scanning in two planes (sagittal and transverse), utilizing color or power Doppler and differentiating CSP from other low‐lying pregnancies. The CSP classification is described in detail and is based on the location of the largest part of the gestational sac relative to the uterine cavity and serosal lines. This descriptive classification is recommended for clinical use to stimulate uniform description and evaluation. Such a standardized sonographic evaluation of CSP in the first trimester is essential for early diagnosis and management, helping to prevent life‐threatening complications and to preserve fertility. Training sonographers in detailed evaluation techniques and promoting awareness of CSP are critical. The structured approach to CSP diagnosis presented herein is supported by a free e‐learning course available online. © 2024 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology. [ABSTRACT FROM AUTHOR]

Quiescence promotes resilience of neural stem cells to cellular stress and aging. Likewise, in glioma tumour/glioma stem cell populations, quiescent/slow-cycling states impart resistance to cellular stress and chemoradiation. Emerging evidence suggests that the molecular signatures of quiescent neural stem cells correlates with the molecular signatures of quiescent glioma stem cells. The few signals that have been experimentally interrogated, suggest these pathways are also functionally conserved. There are multiple challenges in identifying and tracking quiescent neural stem cells and glioma stem cells. Recent advances in methodologies such as intravital imaging, electroporation models of brain cancer and single-cell data tools are overcoming these challenges, which may accelerate the development of targeted therapeutics. Quiescence is a prolonged but reversible state of cell-cycle arrest that is an adaptive feature of most adult stem cell populations. In the brain, quiescence helps to protect adult neural stem cells from stress and supports lifelong neurogenesis. Unfortunately however, entry into a quiescent or a slow-cycling state is also a malignant feature of brain cancer stem cells. In glioblastoma, where the process has been best characterised, quiescent glioma stem cells preferentially survive chemoradiation, and after therapy, reactivate to regrow the tumour and drive recurrence. In this Review, we discuss the in vitro and in vivo models that have been developed for studying neural stem cell quiescence and how these tools may be used to deepen biological understanding and to develop novel therapies targeting quiescent glioma stem cells. [ABSTRACT FROM AUTHOR]

In this study, we aimed to identify the factors that drive the patterns in beta diversity of fish assemblages on the beaches of the Volta Grande do Xingu, a river stretch under the influence of Belo Monte dam. Fishes were collected using a trawl net in 28 sandy beaches during the low water period of 2021 (each beach was sampled once during this period). Measurements of environmental variables were carried out on-site, while spatial variables were obtained using Asymmetric Eigenvector Maps (AEM). Using the Bray–Curtis dissimilarity index, we calculated beta diversity and conducted a distance-based redundancy analysis (db-RDA) with the dissimilarity matrix to assess its relationship between beta diversity and environmental and spatial variables. Additionally, we performed a variance partition to quantify the pure and shared contributions of the explanatory matrices to our response matrix. The results revealed low beta diversity among the sampled beaches, and that this beta diversity was explained in part by the spatial variables and pH. Our findings underscore the influence of spatial structure on the assembly of local communities, indicating that dispersion processes and spatial connectivity are relevant mechanisms that contribute to the beta diversity of beach fish communities under influence of a reduced flow by a Hydropower Plant. [ABSTRACT FROM AUTHOR]

Concepts of an organism’s biological environment and of niche construction as how organisms alter their environment and that of other organisms now play prominent roles in multiple sub-fields of biology, including ecology, evolution, and development. Some philosophers now use these concepts to understand the dynamics of scientific research. Others note divergences among the concepts of niche and niche construction employed in these biological fields, with implications for their possible conceptual integration. My (Rouse, 2015) account of scientific research as niche constructive and of laws and lawful invariance in scientific practice illuminates these conceptual differences and their implications for integrating those domains of biological research in two ways. First, it accounts for the partial autonomy of these domains and their concepts as characteristic of scientific conceptual development. Second, it provides a more complex understanding of how research domains can be integrated, which shows how those different conceptions of niches and niche construction do not block their appropriate integration. The conclusion situates my account and its application to niche concepts both amid other philosophical uses of niche concepts to understand research environments and as exemplifying my revisionist conception of philosophical naturalism. [ABSTRACT FROM AUTHOR]

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While think tanks are no longer solely a feature of Anglo-Saxon countries, they still appear less prevalent in consensus-oriented and neo-corporatist political regimes. To what extent do central characteristics of these countries shape the organizational characteristics and political activities of think tanks? We theoretically contribute to the existing literature on policy advice by drawing inspiration from niche theory, and empirically complement previous work by focusing on think tanks in Belgium, a country with a crowded and closed advisory landscape. Relying on a combination of data sources, our analysis highlights three central features of think tanks: (1) the long-term and anticipatory character of their policy advice, (2) the evidence-based nature of their policy work, and (3) their consensus-oriented mode of operating. The first two features echo what earlier studies in pluralist setting identified as key distinguishing characteristics. The third feature, their consensus-oriented mode of operating, represents a new element that turns out critical for understanding the niche of think tanks in Belgium. Its consensus-style tradition shows not only in how think tanks position themselves externally, but also in their internal organizational structure. Points for practitioners: - Think tanks have potential to be key providers of policy advice, also in relatively closed systems with neo-corporatist traits. - In such settings, think tanks especially benefit from a consensual mode of operating, both internally and externally. - The long-term orientation of think tanks can set them apart from other providers of policy advice, such as interest groups and political party think tanks. [ABSTRACT FROM AUTHOR]

Abstract Telomeres are pivotal determinants of cell stemness, organismal aging, and lifespan. Herein, we examined similarities in telomeres of Arabidopsis thaliana, mice, and humans. We report the common traits, which include their composition in multimers of TTAGGG sequences and their protection by specialized proteins. Moreover, given the link between telomeres, on the one hand, and cell proliferation and stemness on the other, we discuss the counterintuitive convergence between plants and mammals in this regard, focusing on the impact of niches on cell stemness. Finally, we suggest that tackling the study of telomere function and cell stemness by taking into consideration both plants and mammals can aid in the understanding of interconnections and contribute to research focusing on aging and organismal lifespan determinants.

Abstract Spermatogonial stem cells (SSCs) play a crucial role in the male reproductive system, responsible for maintaining continuous spermatogenesis. The microenvironment or niche of SSCs is a key factor in regulating their self-renewal, differentiation and spermatogenesis. This microenvironment consists of multiple cell types, extracellular matrix, growth factors, hormones and other molecular signals that interact to form a complex regulatory network. This review aims to provide an overview of the main components of the SSCs microenvironment, explore how they regulate the fate decisions of SSCs, and discuss the potential impact of microenvironmental abnormalities on male reproductive health. Graphical Abstract

Abstract Climate and land use/land cover (LULC) changes have far-reaching effects on various biological processes in wildlife, particularly interspecific interactions. Unfortunately, interspecific interactions are often overlooked when assessing the impacts of environmental changes on endangered species. In this study, we examined niche similarities and habitat overlaps between wild Crested Ibis and sympatric Egret and Heron species (EHs) in Shaanxi, China, using Ecological niche models (ENMs). We aimed to forecast potential alterations in habitat overlaps due to climate and LULC changes. The results showed that although EHs possess a broader niche breadth compared to the Crested Ibis, they still share certain niche similarities, as indicated by Schoener’s D and Hellinger’s I values exceeding 0.5, respectively. Notably, despite varying degrees of habitat reduction, the shared habitat area of all six species expands with the changes in climate and LULC. We suggest that with the climate and LULC changes, the habitats of sympatric EHs are likely to suffer varying degrees of destruction, forcing them to seek refuge and migrate to the remaining wild Ibis habitat. This is primarily due to the effective conservation efforts in the Crested Ibis habitat in Yangxian County and neighboring areas. Consequently, due to the niche similarity, they will share and compete for limited habitat resources, including food and space. Therefore, we recommend that conservation efforts extend beyond protecting the Crested Ibis habitat. It is crucial to control human activities that contribute to LULC changes to safeguard the habitats of both Crested Ibis and other sympatric birds.

Nowadays, edge computing has been applied for providing various intelligent services, because it can provide ultra-low data transmission delay between user devices and service platforms, by placing several edge servers near users. Edge server placement (ESP) is one of the most critical problems, which greatly influences resource efficiency and service quality by deciding positions where each edge server is placed. As ESP problem is generally a multi-modal and discrete optimization problem with high dimension, this paper proposes a novel niching genetic algorithm (NichingGA) to provide ESP solutions with optimized average response time. The main idea of NichingGA is first dividing the population into several niches and establishing an elite niche. Then, inspired by heterosis in biology, NichingGA produces more diverse offspring by crossing individuals across niches, for improving the global search capability. NichingGA is evaluated by extensive experiments and proven to have better performance than 11 up-to-date approaches in improving the overall request response time. [ABSTRACT FROM AUTHOR]

Background: The trend of increasing caesarean section (CS) rates brings up questions related to subfertility. Research regarding the influence of CS on assisted reproduction techniques (ART) is conflicting. A potential mechanism behind CS-induced subfertility is intra uterine fluid resulting from a caesarean scar defect or niche. The vaginal microbiome has been repeatedly connected to negative ART outcomes, but it is unknown if the microbiome is changed in relation to a niche. Methods: This systematic review describes literature investigating the effect of a niche on live birth rates after assisted reproduction. Furthermore, studies investigating a difference in microbial composition in subfertile persons with a niche compared to no niche are evaluated. Pubmed, Embase and Web of Science were searched on March 2023 for comparative studies on both study questions. Inclusion criteria were i.e., English language, human-only studies, availability of the full article and presence of comparative pregnancy data on a niche. The quality of the included studies and their risk of bias were assessed using the Newcastle-Ottawa scale for cohort studies. The results were graphically displayed in a forest plot. Results: Six retrospective cohort studies could be included on fertility outcomes, with a total of 1083 persons with a niche and 3987 without a niche. The overall direction of effect shows a negative impact of a niche on the live birth rate (pooled aOR 0.58, 95% CI 0.48-0.69) with low-grade evidence. Three studies comparing the microbiome between persons with and without a CS could be identified. Conclusion: There is low-grade evidence to conclude that the presence of a niche reduces live birth rates when compared to persons without a niche. The theory that a caesarean has a negative impact on pregnancy outcomes because of dysbiosis promoted by the niche is interesting, but there is no sufficient literature about this. [ABSTRACT FROM AUTHOR]

Approximately 60% of patients undergoing Cesarean sections may develop Cesarean Scar Defect (CSD), presenting a significant clinical challenge amidst the increasing Cesarean section rates. This condition, marked by a notch in the anterior uterine wall, has evolved as a notable topic in gynecological research. The multifactorial origins of CSD can be broadly classified into labor-related factors, patients' physical conditions, and surgical quality. However, conflicting influences of certain factors across studies make it challenging to determine effective preventive strategies. Additionally, CSD manifests with diverse symptoms, such as abnormal uterine bleeding, dysmenorrhea, chronic pelvic pain, dyspareunia, secondary infertility, and Cesarean scar pregnancy. Some symptoms are often attributed to other diagnoses, leading to delayed treatment. The quandary of when and how to manage CSD also adds to the complexity. Despite the development of various therapies, clear indications and optimal methods for specific conditions remain elusive. This longstanding challenge has troubled clinicians in both identifying and addressing this iatrogenic disease.Recent studies have yielded some compelling consensuses on various aspects of CSD. This review aims to consolidate the current literature on every facet of CSD. We hope to raise awareness among clinicians about this clinical problem, encouraging more relevant research to unveil the complete picture of CSD.