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Aim: Our aims are: (1) to highlight the power of dynamic occupancy models for analysing species range dynamics while accounting for imperfect detection; (2) to emphasize the flexibility to model effects of environmental covariates in the dynamics parameters (extinction and colonization probability); and (3) to illustrate the development of predictive maps of range dynamics by projecting estimated probabilities of occupancy, local extinction and colonization. Location: Switzerland. Methods: We used data from the Swiss breeding bird survey to model the Swiss range dynamics of the European crossbill (Loxia curvirostra) from 2000 to 2007. Within-season replicate surveys at each 1 km 2 sample unit allowed us to fit dynamic occupancy models that account for imperfect detection, and thus estimate the following processes underlying the observed range dynamics: local extinction, colonization and detection. For comparison, we also fitted a model variant where detection was assumed to be perfect. Results: All model parameters were affected by elevation, forest cover and elevation-by-forest cover interactions and exhibited substantial annual variation. Detection probability varied seasonally and among years, highlighting the need for its estimation. Projecting parameter estimates in environmental or geographical space is a powerful means of understanding what the model is telling about covariate relationships. Geographical maps were substantially different between the model where detection was estimated and that where it was not, emphasizing the importance of accounting for imperfect detection in studies of range dynamics, even for high-quality data. Main conclusions: The study of species range dynamics is among the most exciting avenues for species distribution modelling. Dynamic occupancy models offer a robust framework for doing so, by accounting for imperfect detection and directly modelling the effects of covariates on the parameters that govern distributional change. Mapping parameter estimates modelled by spatially indexed covariates is an under-used way to gain insights into dynamic species distributions.

Determining the thermal profile of ignition is important because the desired ignition behavior varies with the objective. For example, extended ignition prolongs the time that the engine runs; however, fast ignition offers a higher power gain. The pollution caused by undesirable chemical reactions, as determined by the ignition profile, is another important aspect. Based on a previously developed method, we examined the impact of different theoretical particle size distributions (PSDs) on the thermal ignition profile. We compared different PSDs of polydispersed fuel spray with normal distributions with various means, each corresponding to the same fuel volume.  Our results revealed a significant dependence of thermal ignition on the PSD. Systems that comprised only low-radius droplets did not reach ignition, whereas systems with only high-radius droplets required a long time to establish ignition. Moreover, the change in the mean droplet radius unexpectedly resulted in a double hump in the maximum temperature of the combustion process.

Entrepreneurial ecosystems (EEs) are viewed as the combination or interaction of elements producing shared innovative and cultural values that support entrepreneurial activities within a territory. The literature has mainly taken a static view of the concept and has analyzed these ecosystems at national or at NUTS-2 regional level. This paper proposes the NUTS-3 provincial level as a spatial unit for measuring EEs in a dynamic perspective and focuses on the Italian case using data for the 2000–2018 period. The choice of NUTS-3 provinces is supported by theoretical arguments and it is confirmed by empirical results, which show some degree of heterogeneity in the level of EEs across provinces and some spatial patterns that would have been ignored using larger spatial units. The temporal dimension also reveals some intra-distribution mobility in the cross-sectional values of the provincial EE index. The paper contributes to advancing the research on EEs, has implications for policymakers and practitioners, and suggests directions for future studies.

Purpose The purpose of this paper is to examine the transformation of the perspective applied to distribution structures in the late 1900s. This change implied that the previous focus on channel management by a channel captain was abandoned because of changes in the business reality. This perspective was replaced by models and concepts featuring collaboration and joint coordination between actors and relationships embedded in networks. Design/methodology/approach Changes of perspectives on phenomena are assumed to occur through the dynamic interplay between business reality, the conceptualisation of this reality and the managerial recommendations derived from this conceptualisation. The study is based on a thorough longitudinal literature review. Findings Shifts of perspectives occur when there is an increasing mismatch between the current business reality and mainstream conceptualisations. In this transformation, new constructs are required to illustrate new aspects of the business reality, exemplified in the study by interaction and networks. Some established concepts lose their significance, illustrated by the channel captain. Others may be re-interpreted, as is the case with the power concept. The study also shows that “forgotten” conceptualisations can be re-wakened, exemplified by the view of distribution structures as network constellations. In turn, these changes in the conceptualisation of distribution impact the managerial recommendations. Originality/value To the best of the author’s knowledge, there are no previous studies analysing how the perspective on a certain phenomenon changes through the dynamic interplay between business reality, conceptualisations and managerial recommendations.

Aim Keteleeria, a relict genus of the Pinaceae family, flourished before the Quaternary ice age but has since experienced a significant decline, with many of its species now critically endangered and classified as key protected species. However, the phylogenetic relationships, taxonomic status, and biogeographic history of Keteleeria remain incompletely understood, posing significant challenges for its conservation and genetic improvement efforts. Here, we reconstruct the first molecular phylogeny of Keteleeria. Location China. Methods In this study, we applied genotyping‐by‐sequencing (GBS) technology to sequence 13 taxa of Keteleeria, with Abies and Cedrus as outgroups. Results A robust phylogenetic tree of Keteleeria was constructed, revealing six clades and resolving the evolutionary relationships of nearly all the taxa. Estimation of the divergence time and reconstruction of the ancestral area indicate that extant Keteleeria originated on the Yunnan–Kweichow Plateau during the Late Cretaceous and underwent multiple dispersal events throughout their evolutionary history. Predictive modelling of Keteleeria distribution dynamics revealed that its range during the Last Glacial Maximum (LGM) was broader than that during the Last Interglacial (LIG). Under future climate warming scenarios, its highly suitable habitat is projected to significantly decrease. In particular, under the RCP8.5 scenario, the area of highly suitable habitats will experience the most significant reduction. Temperature, rather than precipitation, was identified as the dominant factor shaping the patterns of Keteleeria distribution. Main Conclusions We constructed a robust phylogenetic tree, resolving the evolutionary relationships of nearly all the taxa. The results indicate that the evolutionary history of Keteleeria is complex; Keteleeria originated on the Yunnan–Kweichow Plateau during the Late Cretaceous and underwent multiple dispersal events. By predicting the dynamics of the Keteleeria distribution, we found that under future climate warming scenarios, its highly suitable habitat is projected to significantly decrease. This study provides important insights into the taxonomy of Keteleeria, establishes a theoretical foundation for a deeper understanding of its evolutionary history, and offers theoretical support for developing effective conservation strategies to address the impacts of climate change.

Neural Architecture Search (NAS) has demonstrated state-of-the-art performance on various computer vision tasks. Despite the superior performance achieved, the efficiency and generality of existing methods are highly valued due to their high computational complexity and low generality. In this paper, we propose an efficient and unified NAS framework termed DDPNAS via dynamic distribution pruning, facilitating a theoretical bound on accuracy and efficiency. In particular, we first sample architectures from a joint categorical distribution. Then the search space is dynamically pruned and its distribution is updated every few epochs. With the proposed efficient network generation method, we directly obtain the optimal neural architectures on given constraints, which is practical for on-device models across diverse search spaces and constraints. The architectures searched by our method achieve remarkable top-1 accuracies, 97.56 and 77.2 on CIFAR-10 and ImageNet (mobile settings), respectively, with the fastest search process, i.e., only 1.8 GPU hours on a Tesla V100. Codes for searching and network generation are available at: https://openi.pcl.ac.cn/PCL_AutoML/XNAS.

China has entered a critical stage of urbanization transition but still faces unbalanced regional development and uncoordinated urban–rural integration. Studying the regional differences in spatial determinants of land urbanization (LU) is crucial to achieving coordinated regional development of urbanization. However, the spatial determinants of LU remain unclear, especially in terms of their regional differences. Therefore, this study introduced dynamic distribution and spatial analysis to measure regional differences in spatial determinants of LU in China. During 1990–2020, the imbalance of LU in China was constantly decreasing, and the differences in LU among different regions were also decreasing. LU in China had significant spatial dependence and spatial spillover effects, and the trend of group development was gradually becoming obvious. LU in eastern region was more affected by natural factors than in central and western regions, while central and western regions were more affected by socioeconomic factors than in eastern region. This study can provide a scientific reference for understanding the spatial disequilibrium of LU and promoting the regional implementation of LU coordinated development.

Nonoxidative ethanol metabolites have been reported as ethanol biomarkers in clinical and forensic cases. However, their forensic toxicokinetics are still unclear. The study aimed to simultaneously research the postmortem distribution and dynamic distribution of ethanol and its nonoxidative metabolites in 62 poisoned rabbits. Firstly, 32 rabbits were randomly divided into three groups and sacrificed after three doses ethanol, and their organs were collected to study the postmortem distribution of ethanol and its nonoxidative metabolites. The results showed that the distribution trends of ethanol and its nonoxidative metabolites were basically same between different groups, and ethanol could be better detected by collecting body fluids, while the nonoxidative metabolites could be better detected by collecting the heart, liver, kidney and testis. Secondly, 30 rabbits after 1/2LD 50 ethanol intragastric administration were sacrificed at 10 time points, and their organs were collected to study the dynamic distribution of ethanol and its nonoxidative metabolites. The results showed the concentrations of ethanol and its nonoxidative metabolites increased with time and then decreased. All analytes could be detected in all samples within 8 h, with the exception of ethyl oleate, which kept high level in muscle and vitreous humor, and could be detected within 4 h.

Ecosystem health in the Yangtze River basin (YRB) shows significant regional differences. Analysis of regional differences and drivers of ecosystem health in YRB is of practical significance for sustainable basin ecological management. However, existing studies lack research on regional differences and driving forces of ecosystem health, especially in big basin regions. Based on multi-source data, this study adopted spatial statistics and distribution dynamics models to quantitatively analyze the regional differences of ecosystem health in the YRB during 2000–2020 and employed the spatial panel model to reveal the driving forces of ecosystem health in the YRB. The ecosystem health index of the upper, middle, and lower reaches of YRB and the entire basin in 2020 was 0.753, 0.781, 0.637, and 0.742, respectively, while they all decreased during 2000–2020. Regional differences in YRB ecosystem health increased during 2000–2020. From the perspective of dynamic evolution, low-level and high-level ecosystem health units evolved to high-level, while medium-high-level ecosystem health units evolved to low-level. High-high (accounting for 30.372% in 2020) and low-low (accounting for 13.533% in 2020) were the main cluster types. Regression result showed that urbanization was the main reason for ecosystem health deterioration. The findings can provide enlightenment to further understand the regional differences of ecosystem health in YRB and provide theoretical reference for the coordinated management of ecosystem at macro-level and the differential regulation of local ecosystem at micro-level in the basin region. Graphical abstract

Background Leonurus japonicus , a significant medicinal plant known for its therapeutic effects on gynecological and cardiovascular diseases, has genetic diversity that forms the basis for germplasm preservation and utilization in medicine. Despite its economic value, limited research has focused on its genetic diversity and divergence. Results The avg. nucleotide diversity of 59 accessions from China were 0.00029 and hotspot regions in petN-psbM and rpl32-trnL (UAG) spacers, which can be used for genotype discrimination. These accessions divided into four clades with significant divergence. The four subclades, which split at approximately 7.36 Ma, were likely influenced by the Hengduan Mountains uplift and global temperature drop. The initial divergence gave rise to Clade D, with a crown age estimated at 4.27 Ma, followed by Clade C, with a crown age estimated at 3.39 Ma. The four clades were not showed a clear spatial distribution. Suitable climatic conditions for the species were identified, including warmest quarter precipitation 433.20 mm ~ 1,524.07 mm, driest month precipitation > 12.06 mm, and coldest month min temp > -4.34 °C. The high suitability distribution showed contraction in LIG to LGM, followed by expansion from LGM to present. The Hengduan Mountains acted as a glacial refuge for the species during climate changes. Conclusions Our findings reflected a clear phylogenetic relationships and divergence within species L. japonicus and the identified hotspot regions could facilitate the genotype discrimination. The divergence time estimation and suitable area simulation revealed evolution dynamics of this species and may propose conservation suggestions and exploitation approaches in the future.