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Construction land reduction is an important means of promoting the effective allocation of factors and the optimization of industrial structure. Based on analyses of the impact mechanism of construction land reduction on industrial structure rationalization and supererogation, this study adopts the difference‐in‐difference model and threshold regression model to analyze the effects of construction land reduction. The results are as follows: (1) Construction land reduction significantly improves industrial structure rationalization and supererogation, and the positive effect clearly accumulates over time. After PSM‐DID and other series of robustness tests, the conclusion is still valid. (2) Construction land reduction in the outer suburban areas has a greater positive impact on industrial structure rationalization and supererogation than that in other suburban areas. (3) When the scale of the reduction exceeds a certain threshold, rural financial development can significantly promote industrial structure rationalization and supererogation. It is necessary to rationally plan the layout of industry, establish a mechanism of cross‐regional allocation of the reduction index, and provide replicable experiences for popularizing construction land reduction throughout the whole country. [ABSTRACT FROM AUTHOR]

Under the background of supply side structural reform of the land market, this paper constructs a location choice behavior model of reduction from the perspective of rent maximization, explores how these factors affect the industrial land reduction location choice. We consider 100 industrial parcels in the suburbs of Shanghai as an example to analyze. It is found that the enterprises in development zones have greater advantages in economies of scale, labor productivity, pollution treatment, and tax payments than enterprises outside the development zone, so the low‐efficiency enterprises outside the development zones are the preferred objects of reduction. The suburban areas have a stronger attraction than the outer suburbs in the process of location choice, and the closer the city center is, the more obvious the location advantages of enterprises in development zones. Under the control of the total amount of construction land, the land use structure should be constantly adjusted, inefficient enterprises outside the development zone should be preferred to the reduction object, and the government should actively guide enterprises to enter the development zones. [ABSTRACT FROM AUTHOR]

Chancelloriids are a group of enigmatic sessile animals that are covered with sclerites shaped as rosettes of spines, producing an appearance like that of a barrel cactus. They are known only from Cambrian rocks. Isolated sclerites of chancelloriids are widespread in small shelly faunas, but they have proven difficult to treat taxonomically due to the variation within and between individual animals. We report on large samples of chancelloriid sclerites from the Meishucunian (pre-trilobitic Lower Cambrian) of eastern Yunnan Province, China, including material from the Dahai Member of the Zhujiaqing Formation (the Zhujiaqing section, Dahai, Huize County) and the Shiyantou Formation (the Xiaotan section, Yongshan County). The material from the Dahai Member appears to come from a single species, Chancelloriella irregularis. Statistical analysis of morphotype co-occurrences in different samples suggests that several species are represented in the material from the Shiyantou Formation, which we herein tentatively place in four species, Allonnia erromenosa, Allonnia tetrathallis, Archiasterella charma sp. nov. and Archiasterella cf. pentactina. We suggest therefore that careful study of large collections of isolated chancelloriid sclerites permits the identification of different species, opening the possibility of their use in evolutionary or stratigraphical studies. In particular, in South China, it seems that Chancelloriella irregularis is characteristic of rocks of the Paragloborilus subglobosus - Purella squamulosa Assemblage Zone and the Watsonella crosbyi Assemblage Zone, whilst Archiasterella and Allonnia first appear in the overlying Sinosachites flabelliformis - Tannuolina zhangwentangi Assemblage Zone. C. irregularis is thus amongst the oldest well-characterized chancelloriids, and the irregularity and poor organization of its sclerites relative to those of younger forms support the hypothesis that chancelloriid sclerites are compound structures arising from the fusion of originally separate elements, perhaps homologous with sclerites of halkieriids and other coeloscleritophorans. The similarity between the arrangement of rays in a chancelloriid sclerite and the arrangement of bubbles in small bubble clusters suggests that in many cases, aspects of the form of chancelloriid sclerites are the result of simple physical processes. [ABSTRACT FROM AUTHOR]

Environmental regulation is an important tool for local governments to intervene in environmental governance. Based on 2008–2017 panel data on 289 cities in China, this paper analyzes the impact of environmental regulation on the supply efficiency of environmental public services and explores whether environmental decentralization changes the effect of environmental regulation. The results show that environmental regulation can significantly improve the supply efficiency of environmental public services, and this finding still holds after a series of robustness tests. The main reason is the improvement in green technology innovation capabilities caused by environmental regulation. Environmental regulation has a more significant positive effect on the supply efficiency of environmental public services in regions with a higher local government governance capacity, lower levels of fiscal decentralization, and a higher pollutant emission intensity. A moderate level of environmental decentralization helps to better promote the supply efficiency of environmental public services through environmental regulation. When the level of environmental decentralization lies between 0.362 and 1.353, environmental regulation effectively improves the supply efficiency of environmental public services. [ABSTRACT FROM AUTHOR]

As a significant evolutionary innovation, multicellularity has independently evolved multiple times throughout the evolutionary history of eukaryotes, making a substantial contribution to their diversity. In retracing the multicellularity of eukaryotes, deep‐time fossil records play an irreplaceable role. In this paper, we report a new acritarch Concavaesphaera ornata gen. et sp. nov. from the early Cambrian Kuanchuanpu biota (535 Ma). These fossils are generally spherical, with diameters ranging from 450 to 950 μm, and feature an envelope with complex ornament. Inside, there are two groups of cells varying in size. Larger cells are relatively fewer in number and each resides within a sac‐like cavity distributed along the inner wall of the envelope. Statistical data show a positive correlation between the diameter and cavity volume during the development of large cells. Small cells are numerous, have a diameter of about 15 μm, and fill the entire interior of the specimens. We interpret the large cells as reproductive cells and the small cells as somatic cells. These observations show that Concavaesphaera evolved multicellular complexity equivalent to that of modern Volvox, with germ‐soma differentiation and separation. Available evidence suggests that the similarities between Concavaesphaera and Volvox are more likely to be the result of convergent evolution. Therefore, Concavaesphaera may represent an extinct multicellular eukaryote which evolved during the Cambrian explosion and probably documented an independent innovation of multicellularity in eukaryotic evolutionary history. This implies that multicellularity evolved many more times in eukaryotes than previously estimated. [ABSTRACT FROM AUTHOR]

Shell decollation is a growth strategy that has been adopted by a number of invertebrate taxa to offset the metabolic and ecological disadvantages of shell growth. However, little is known about the origin and evolution of this process. We here describe well‐preserved specimens of the hyolith Cupitheca decollata sp. nov. preserving the decollation process, from the early Cambrian Yu'anshan Formation (c. 518 Ma) of South China. Based on a large number of specimens collectively representing different developmental stages, we use high‐resolution X‐ray microtomography and scanning electronic microscopy to reconstruct the process of decollation in this taxon. Cupitheca is among the earliest known small shelly fossils, and thus our discovery confirms that periodic decollation had evolved by the onset of the Cambrian explosion, reflecting the high intensity of the predator–prey arms race in early Cambrian ecosystems. A comparison between the decollation processes of Cupitheca and other shelly invertebrates suggests that periodic decollation and the associated molecular mechanisms of calcium dissolution, uptake, allocation and deposition may have had multiple independent origins. [ABSTRACT FROM AUTHOR]

Hyoliths were among the earliest biomineralizing metazoans in Palaeozoic marine environments. They have been known for two centuries and widely assigned to lophotrochozoans. However, their origin and relationships with modern lophotrochozoan clades have been a longstanding palaeontological controversy. Here, we provide broad microstructural data from hyolith conchs and opercula from the lower Cambrian Xinji Formation of North China, including two hyolithid genera and four orthothecid genera as well as unidentified opercula. Results show that most hyolith conchs contain a distinct aragonitic lamellar layer that is composed of foliated aragonite, except in the orthothecid New taxon 1 that has a crossed foliated lamellar microstructure. Opercula are mostly composed of foliated aragonite and occasionally foliated calcite. These blade or lath‐like microstructural fabrics coincide well with biomineralization of Cambrian molluscs rather than lophophorates, as exemplified by the Cambrian members of the tommotiid‐brachiopod linage. Accordingly, we propose that hyoliths and molluscs might have inherited their biomineralized skeletons from a non‐mineralized or weakly mineralized common ancestor rather than as a result of convergence. Consequently, from the view of biomineralization, the homologous shell microstructures in Cambrian hyoliths and molluscs strongly strengthen the phylogenetic links between the two groups. [ABSTRACT FROM AUTHOR]

The upper Qigeblaq Formation (Fm) dolostones and the Yurtus Fm phosphatic cherts, black shales, limestones, and dolostones are widely distributed in the Precambrian/Cambrian transitional succession of the Aksu-Wushi area. Negative δ13C excursion above the Yurtus Fm/Qigeblaq Fm boundary was determined in this study. The pronounced negative carbon isotope excursion occurs in the phosphatic chert layers at the bottom of the Cambrian Yurtus Fm, below which the first appearance of the Asteridium-Heliosphaeridium-Comasphaeridium (AHC) acritarch assemblage zone. The δ13C curve of the lower part of the Yurtus Fm in the Aksu-Wushi area was found to be correlated with the early Cambrian δ13C curves of the Zhujiaqing Fm (Daibu Member), the lower part of the Yanjiahe Fm on the Yangtze Platform in China, the lower Tal Fm in India, the Sukharikha Fm in Siberia, and the upper part of the Tsagaan Oloom Fm in Mongolia through biostigraphy. The lower part of the Yurtus Fm in the Tarim Basin is at the Nemakit-Daldynian stage, and the Precambrian/Cambrian boundary of the Aksu-Wushi area may be located in the phosphatic chert unit which just below the first appearance AHC acritarch assemblage zone. The negative δ13C excursion (N1) across the Precambrian/Cambrian boundary in the studied section may have resulted from oceanic overturning and sea level rise. [ABSTRACT FROM AUTHOR]