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Soil fauna, key indicators of grassland ecosystem health, face significant threats from the vast amounts of chemical pollutants released by human activities. These organisms are crucial for fundamental processes such as litter decomposition and carbon cycling. However, the response of soil animal communities and their functional dynamics to environmental chemical stress remains poorly understood. To investigate this, we conducted a naphthalene addition and litterbag experiment in the Bashang Grassland, located on the southern Inner Mongolia Plateau, to analyze its effects on soil fauna and litter decomposition. The investigated soil fauna groups included Arachnida (Arachnids), Insecta (Insects), Collembola (Springtails), Enoplea (enopleans), and Chromadorea (chromadoreans). The litter composition included Leymus chinensis, Stipa krylovii, Artemisia, Saussurea amara, and Artemisia giraldii. The findings indicated that a high diversity of soil fauna enhanced the decomposition of litter and the release of organic carbon from the litter. While the addition of naphthalene decreased both the abundance of soil fauna and the rate of litter decomposition, it specifically increased the relative proportion of Collembola (Springtails). Microfauna and mesofauna (0.1–2.0 mm) contributed more to the loss of litter mass and the release of organic carbon from the litter than macrofauna (2.0–4.0 mm). The effects of diverse soil fauna on litter decomposition and soil organic carbon accumulation were diminished by naphthalene exposure. This study further reveals the relationship between composite soil fauna diversity, litter decomposition, and soil organic carbon under chemical stress, highlighting the threat of environmental pollution to ecosystem health. It also enriches our understanding of the complexity of grassland ecosystems, especially in response mechanisms under chemical pollution stress.

Abstract Background Gynostemma pentaphyllum, an ancient Chinese herbal medicine, serves as a natural source of gypenosides with significant medicinal properties. Basic helix-loop-helix (bHLH) transcription factors play pivotal roles in numerous biological processes, especially in the regulation of secondary metabolism in plants. However, the characteristics and functions of the bHLH genes in G. pentaphyllum remain unexplored, and their regulatory role in gypenoside biosynthesis remains poorly elucidated. Results This study identified a total of 111 bHLH members in G. pentaphyllum (GpbHLHs), categorizing them into 26 subgroups based on shared conserved motif compositions and gene structures. Collinearity analysis illustrated that segmental duplications predominately lead to the evolution of GpbHLHs, with most duplicated GpbHLH gene pairs undergoing purifying selection. Among the nine gypenoside-related GpbHLH genes, two GpbHLHs (GpbHLH15 and GpbHLH58) were selected for further investigation based on co-expression analysis and functional prediction. The expression of these two selected GpbHLHs was dramatically induced by methyl jasmonate, and their nuclear localization was confirmed. Furthermore, yeast one-hybrid and dual-luciferase assays demonstrated that GpbHLH15 and GpbHLH58 could bind to the promoters of the gypenoside biosynthesis pathway genes, such as GpFPS1, GpSS1, and GpOSC1, and activate their promoter activity to varying degrees. Conclusions In conclusion, our findings provide a detailed analysis of the bHLH family and valuable insights into the potential use of GpbHLHs to enhance the accumulation of gypenosides in G. pentaphyllum.

Scandium aluminum nitride (ScAlN) has recently emerged as an attractive material for integrated photonics due to its favorable nonlinear optical properties and compatibility with complementary metal–oxide semiconductor (CMOS) fabrication. Despite the promising and versatile material properties, it is still an outstanding challenge to realize low-loss photonic circuits on thin-film ScAlN-on-insulator wafers. Here, we present a systematic study on the material quality of sputtered thin-film Sc0.1Al0.9N produced in a CMOS-compatible 200 mm line, including its crystallinity, roughness, and second-order optical nonlinearity, and developed an optimized fabrication process to yield 400 nm thick, fully etched waveguides. With surface polishing and annealing, we achieve micro-ring resonators with an intrinsic quality factor as high as 1.47 × 105, corresponding to a propagation loss of 2.4 dB/cm. These results serve as a critical step toward developing future large-scale, low-loss photonic integrated circuits based on ScAlN.

Light is a key factor affecting the growth and quality formation of Dendrobium officinale Kimura et Migo. In this study, we used D. officinale under different light conditions as experimental materials to explore the key genes that regulate its polysaccharide content. In addition, we cloned the UGPase gene and validated the gene by bioinformatics analysis and real-time quantitative PCR. Compared with the natural light control group, 494, 1630 and 599 differentially expressed genes were screened under different light quality conditions of red, blue and yellow, respectively. GO and KEGG enrichment analyses of these differentially expressed genes showed that the differentially expressed genes were enriched in the light signal transduction process under different light quality conditions. Bioinformatics analyses showed that the sequences of the genes were highly conserved with the sequences of the UGPase genes of other species, and had the highest sequence similarity with Phalaenopsis, which is also a member of the orchid family. Real-time quantitative PCR results showed that red light had the most significant promoting effect on the UGPase gene of D. officinale. In this study, we applied high-throughput sequencing technology to establish a transcriptome database of D. officinale under different light conditions and obtained a large amount of transcriptional information about D. officinale. The related genes affecting the quality of D. officinale were analysed at the transcriptional level, and the D. officinale UGPase gene was cloned, and its expression was analysed in different tissues and under different light conditions.

Abstract Background Cinnamomum cassia Presl, classified in the Lauraceae family, is widely used as a spice, but also in medicine, cosmetics, and food. Aroma is an important factor affecting the medicinal and flavoring properties of C. cassia, and is mainly determined by volatile organic compounds (VOCs); however, little is known about the composition of aromatic VOCs in C. cassia and their potential molecular regulatory mechanisms. Here, integrated transcriptomic and volatile metabolomic analyses were employed to provide insights into the formation regularity of aromatic VOCs in C. cassia bark at five different harvesting times. Results The bark thickness and volatile oil content were significantly increased along with the development of the bark. A total of 724 differentially accumulated volatiles (DAVs) were identified in the bark samples, most of which were terpenoids. Venn analysis of the top 100 VOCs in each period showed that twenty-eight aromatic VOCs were significantly accumulated in different harvesting times. The most abundant VOC, cinnamaldehyde, peaked at 120 months after planting (MAP) and dominated the aroma qualities. Five terpenoids, α-copaene, β-bourbonene, α-cubebene, α-funebrene, and δ-cadinene, that peaked at 240 MAP could also be important in creating C. cassia’s characteristic aroma. A list of 43,412 differentially expressed genes (DEGs) involved in the biosynthetic pathways of aromatic VOCs were identified, including phenylpropanoids, mevalonic acid (MVA) and methylerythritol phosphate (MEP). A gene-metabolite regulatory network for terpenoid and phenylpropanoid metabolism was constructed to show the key candidate structural genes and transcription factors involved in the biosynthesis of terpenoids and phenylpropanoids. Conclusions The results of our research revealed the composition and changes of aromatic VOCs in C. cassia bark at different harvesting stages, differentiated the characteristic aroma components of cinnamon, and illuminated the molecular mechanism of aroma formation. These foundational results will provide technical guidance for the quality breeding of C. cassia.

With the swift advancement of cloud computing and the Internet of Things (IoT), to address the issue of massive data storage, IoT devices opt to offload their data to cloud servers so as to alleviate the pressure of resident storage and computation. However, storing local data in an outsourced database is bound to face the danger of tampering. To handle the above problem, a verifiable database (VDB), which was initially suggested in 2011, has garnered sustained interest from researchers. The concept of VDB enables resource-limited clients to securely outsource extremely large databases to untrusted servers, where users can retrieve database records and modify them by allocating new values, and any attempts at tampering will be detected. This paper provides a systematic summary of VDB. First, a definition of VDB is given, along with correctness and security proofs. And the VDB based on commitment constructions is introduced separately, mainly divided into vector commitments and polynomial commitments. Then VDB schemes based on delegated polynomial functions are introduced, mainly in combination with Merkle trees and forward-secure symmetric searchable encryption. We then classify the current VDB schemes relying on four different assumptions. Besides, we classify the established VDB schemes built upon two different groups. Finally, we introduce the applications and future development of VDB. To our knowledge, this is the first VDB review paper to date.

Background In a context of long-term highly intensive grazing in grassland ecosystems, a better understanding of how quickly belowground biodiversity responds to grazing is required, especially for soil microbial diversity. Methods In this study, we conducted a grazing experiment which included the CK (no grazing with a fenced enclosure undisturbed by livestock), light and heavy grazing treatments in a desert steppe in Inner Mongolia, China. Microbial diversity and soil chemical properties (i.e., pH value, organic carbon, inorganic nitrogen (IN, ${\mathrm{NH}}_{4}^{+}$ NH 4 + -N and ${\mathrm{NO}}_{3}^{-}$ NO 3 − -N), total carbon, nitrogen, phosphorus, and available phosphorus content) both in rhizosphere and non-rhizosphere soils were analyzed to explore the responses of microbial diversity to grazing intensity and the underlying mechanisms. Results The results showed that heavy grazing only deceased bacterial diversity in the non-rhizosphere soil, but had no any significant effects on fungal diversity regardless of rhizosphere or non-rhizosphere soils. Bacterial diversity in the rhizosphere soil was higher than that of non-rhizosphere soil only in the heavy grazing treatment. Also, heavy grazing significantly increased soil pH value but deceased NH4+-N and available phosphorus in the non-rhizosphere soil. Spearman correlation analysis showed that soil pH value was significantly negatively correlated with the bacterial diversity in the non-rhizosphere soil. Combined, our results suggest that heavy grazing decreased soil bacterial diversity in the non-rhizosphere soil by increasing soil pH value, which may be due to the accumulation of dung and urine from livestock. Our results highlight that soil pH value may be the main factor driving soil microbial diversity in grazing ecosystems, and these results can provide scientific basis for grassland management and ecological restoration in arid and semi-arid area.

As mobile internet and Internet of Things technologies rapidly advance, the amount of spatio-temporal big data have surged, and efficient and secure management solutions are urgently needed. Although cloud storage provides convenience, it also brings significant data security challenges. Blockchain technology is an ideal choice for processing large-scale spatio-temporal big data due to its unique security features, but its storage scalability is limited because the data need to be replicated throughout the network. To solve this problem, a common approach is to combine blockchain with off-chain storage to form a hybrid storage blockchain. However, these solutions cannot guarantee the authenticity, integrity, and consistency of on-chain and off-chain data storage, and preprocessing is required in the setup phase to generate public parameters proportional to the data length, which increases the computational burden and reduces transmission efficiency. Therefore, this paper proposes a collaborative storage mechanism for spatio-temporal big data based on incremental aggregation sub-vector commitments, which uses vector commitment binding technology to ensure the secure storage of on-chain and off-chain data. By generating public parameters of fixed length, the computational complexity is reduced and the communication efficiency is improved while improving the security of the system. In addition, we design an aggregation proof protocol that integrates aggregation algorithms and smart contracts to improve the efficiency of data query and verification and ensure the consistency and integrity of spatio-temporal big data storage. Finally, simulation experiments verify the correctness and security of the proposed protocol, providing a solid foundation for the blockchain-based spatio-temporal big data storage system.

In the period of big data, the Medical Internet of Things (MIoT) serves as a critical technology for modern medical data collection. Through medical devices and sensors, it enables real-time collection of a large amount of patients' physiological parameters and health data. However, these data are often generated in a high-speed, large-scale, and diverse manner, requiring integration with traditional medical systems, which further exacerbates the phenomenon of scattered and heterogeneous medical data. Additionally, the privacy and security requirements for the devices and sensor data involved in the MIoT are more stringent. Therefore, when designing a medical data sharing mechanism, the data privacy protection capability of the mechanism must be fully considered. This paper proposes an alliance chain medical data sharing mechanism based on a dual-chain structure to achieve secure sharing of medical data among entities such as medical institutions, research institutions, and cloud privacy centers, and at the same time provide privacy protection functions to achieve a balanced combination of privacy protection capability and data accessibility of medical data. First, a knowledge technology based on ciphertext policy attribute encryption with zero-knowledge concise non-interactive argumentation is used, combined with the data sharing structure of the federation chain, to ensure the integrity and privacy-protecting capability of medical data. Second, the approach employs certificate-based signing and proxy re-encryption technology, ensuring that entities can decrypt and verify medical data at the cloud privacy center using this methodology, consequently addressing the confidentiality concerns surrounding medical data. Third, an efficient and secure key identity-based encryption protocol is used to ensure the legitimacy of user identity and improve the security of medical data. Finally, the theoretical and practical performance analysis proves that the mechanism is feasible and efficient compared with other existing mechanisms.

Abstract Background Propofol is an intravenous (IV) anesthetic medication widely used for procedural sedation, operative anesthesia, and in intensive care unit (ICU), but the incidence of pain during IV infusion can reach 28–90%. Ketamine can attenuate pain associated with IV propofol injection through local and central analgesic effects. Ketamine is gradually being transitioned to its S-enantiomer, esketamine, which has a similar mechanism of action. The purpose of our study is to determine the half effective dose (ED50), 95% effective dose (ED95), and 99% effective dose (ED99) of esketamine for attenuating propofol injection pain using Dixon’s up-and-down method to provide a reference for optimal dose selection for surgeries and procedures. Methods Thirty gynecological patients undergoing hysteroscopic surgery were enrolled in a sequential method to determine the effective dose of esticketamine for analgesic propofol injection in order of operation. This study was based on the sequential allocation up-and-down rule designed by Dixon, and each patient was induced by esticketamine combined with propofol. During induction, the target dose of esketamine was first given via venous access in the left hand of the patient, and 30 s later, a fixed dose of 2 mg/kg (1 ml/s) of propofol was given. Patient perception of pain was scored with the verbal rating scale (VRS) every 5 s after the start of the propofol infusion, and the evaluation was stopped once the patient became unresponsive. The dosage of esketamine was increased or decreased up or down according to the patient’s pain response. The initial dose of esketamine was 0.2 mg/kg, and the gradient of adjacent dose was 0.02 mg/kg. If the pain response assessment of the upper patient was positive (+), the dose of esselketamine in the next patient was increased by 0.02 mg/kg; if the pain response assessment of the upper patient was negative (−), the dose of esselketamine in the next patient was decreased by 0.02 mg/kg. The tests were carried out sequentially, with the pain response changing from positive to negative or from negative to positive, and the tests were stopped after at least 6 crossover points, and the effective dose of esticketamine was calculated using probit probability regression analysis. Results The ineffective group comprised patients with a positive pain response and the effective group comprised patients with a negative pain response. The 95% CI was set as the confidence interval of effective dose ED value，and we found esketamine’s ED50 = 0.143 mg/kg (0.120, 0.162 mg/kg), ED95 = 0.176 mg/kg (0.159, 0.320 mg/kg), and ED99 = 0.189 mg/kg (0.167, 0.394 mg/kg). The esketamine dose and VRS score during propofol injection were significantly different between the two groups (P

Abstract Background Fairy rings occur in diverse global biomes; however, there is a critical knowledge gap regarding drivers of fairy rings in grassland ecosystems. Grassland fairy rings are characterized belowground by an expanding mycelial front and aboveground by vigorous vegetation rings that develop concentrically with each growing season. We evaluated fairy ring dynamics in a field study conducted in semiarid grasslands to elucidate above- and belowground interactions driving distinct vegetation patterns. We followed this initial field investigation with a complementary greenhouse experiment, using soils collected from specific fairy ring zones (inside, ring-edge, outside) to examine plant-soil-microbial interactions under controlled conditions. We selected Leymus chinensis (a dominant grass) as our model plant species to assess the role of diverse fairy ring microbial communities on plant growth and nutrition. Results In our field study, plants on the ring-edge produced greater shoot biomass with higher concentrations of N and P, compared to plants inside the ring or adjacent (outside) controls. Soil microbial community biomarkers indicate shifts in relative microbial biomass as fairy rings expand. Inside the ring, plant roots showed greater damage from pathogenic fungi, compared to outside or ring-edge. Our greenhouse experiment confirmed that inoculation with live ring-edge soil generally promoted plant growth but decreased shoot P concentration. Inoculation with soil collected from inside the ring increased root pathogen infection and reduced shoot biomass. Conclusion We propose that soil microbial activity within ring-edges promotes plant growth via mobilization of plant-available P or directed stimulation. However, as the ring expands, L. chinensis at the leading edge may increase pathogen accumulation, resulting in reduced growth at the center of the ring in subsequent growing seasons. Our results provide new insights into the plant-soil-microbial dynamics of fairy rings in grasslands, helping to elucidate these mysterious vegetation patterns.

The rapid development of the Internet and Internet of Things has rapidly introduced human society into the information age, and the way of fake news production has been updated, which has greatly affected the normal life of human beings. In order to identify worthless fake news and trace massive fake news data from unknown sources, and share valuable news data to fully disseminate effective real news, news owners usually store news data in cloud. Users of IoT terminals can access news data on demand without storing it locally. However, the authenticity of the fictive newspaper numbers source, which is easy to destroy, and the social media platform. Besides, when massive news data is saved on cloud server, the news owners have to at the risk of lose physical control over news data and it will face the risk of fake news being disseminated and real news being falsified. Thus, this paper proposes a novel mechanism for secure storage of news data using blockchain technology. Firstly, traceability and verification of fake news data is improved by the cooperative storage model on and off the chain. Secondly due to the inability of past polynomial commitment to update the commitment, we will be a hindrance to use polynomial commitment to build a secure authentication protocol. Therefore, in this paper, we design the update algorithm for polynomial commitment in order to be able to guarantee the consistency of on-chain and blockchain database news data.

Abstract Background In clinical practice, sufentanil has a stronger sedative effect on patients than fentanyl at equivalent doses. This study hypothesized that, at equivalent doses, patients undergoing gynaecologic laparoscopic surgery (GLS) receiving fentanyl would have an earlier emergence from anaesthesia (EA), a shorter time to extubation (TE), and a better degree of wakefulness. Therefore, this study evaluated the effects of equipotent doses of fentanyl and sufentanil on the quality of emergence in patients undergoing GLS. Methods One hundred seven patients scheduled for GLS under general anaesthesia were randomly divided into two groups and were induced with 0.35 µg/kg sufentanil (Group S; n = 55) or 3.5 µg/kg fentanyl (Group F; n = 52). When the GLS was almost over, the patient's abdominal cavity was flushed with warm saline, and 5 µg of sufentanil or 50 µg of fentanyl in a double-blind manner was intravenously injected into the patients. The primary outcomes of the study included EA, TE, the rate of leaving the surgical bed voluntarily and the incidence of endotracheal tube tolerance. The Ramsay Sedation Scale (RSS), and Verbal Rating Scale (VRS) scores at 15 and 30 min in the postanaesthesia care unit (PACU), as well as other adverse events, including nausea and vomiting, itching, delirium, dizziness, chills, and respiratory depression (SpO2

Mg alloys possess biodegradability, suitable mechanical properties, and biocompatibility, which make them possible to be used as biodegradable implants. However, the uncontrollable degradation of Mg alloys limits their general applications. In addition to the factors from the metallic materials themselves, like alloy compositions, heat treatment process and microstructure, some external factors, relating to the test/service environment, also affect the degradation rate of Mg alloys, such as inorganic salts, bioorganic small molecules, bioorganic macromolecules. The influence of bioorganic molecules on Mg corrosion and its protection has attracted more and more attentions. In this work, the cutting-edge advances in the influence of bioorganic molecules (i.e., protein, glucose, amino acids, vitamins and polypeptide) and their coupling effect on Mg degradation and the formation of protection coatings were reviewed. The research orientations of biomedical Mg alloys in exploring degradation mechanisms in vitro were proposed, and the impact of bioorganic molecules on the protective approaches were also explored.

The extreme marine environment of the South China Sea Islands, which features high temperatures, high humidity levels and high salt levels, seriously affects the safety of building structures. The durability of concrete can be significantly improved by adding a basalt–polypropylene hybrid fiber, but its bonding mechanism with deformed bars is complicated. Therefore, the bonding performance of hybrid basalt–polypropylene fiber-reinforced concrete and deformed bars was studied by combining experiments and a theoretical analysis. We designed 38 groups of different concrete strengths, different thicknesses of concrete covers, different anchor lengths and different diameters of rebars. The bond strengths, bond–sliding curves and failure forms of each pull specimen were compared and analyzed. The results showed that the failure forms and bond–slip curves of the basalt–polypropylene hybrid fiber-reinforced concrete specimens and the ordinary concrete specimens were essentially the same. Based on the results of the axial tensile tests, an ultimate bond strength prediction model was developed, and a bond–sliding constitutive model for hybrid fiber-reinforced concrete and steel bars was also established.

Reactive powder concrete (RPC) and reinforcements have ultra-high bonding strength and, thus, a potential advantage in improving the connection performance of assembled structures. In this study, four assembled beam–column connections using modified reactive powder concrete (MRPC) under different steel fiber types in critical cast-in-place regions, as well as a monolithic concrete beam–column connection, were tested under low-cyclic loading. The results show that MRPC application in critical cast-in-place region connections significantly improved damage tolerance capacity and load-carrying capacity. End-bent short steel fibers had the most significant crack-resistance effect. Using end-bent long fibers could improve an assembled connection’s ductility by 102%. Straight steel fibers were easily pulled out and had the least inhibitory effect on cracks. Connections using wavy steel fiber had the lowest initial stiffness and shear capacity but the highest energy dissipation capacity. Using 30 mm end-bent steel fiber is recommended for comprehensive seismic performance. The Chinese code overestimated MRPC’s shear contribution. MRPC assembled connections’ crack capacity and shear capacity models were established.

Abstract Callerya speciosa (Champ. ex Benth.) Schot is a traditional Chinese medicine characterized by tuberous roots as the main organ of isoflavonoid accumulation. Root thickening and isoflavonoid accumulation are two major factors for yield and quality of C. speciosa. However, the underlying mechanisms of root thickening and isoflavonoid biosynthesis have not yet been elucidated. Here, integrated morphological, hormonal and transcriptomic analyses of C. speciosa tuberous roots at four different ages (6, 12, 18, 30 months after germination) were performed. The growth cycle of C. speciosa could be divided into three stages: initiation, rapid-thickening and stable-thickening stage, which cued by the activity of vascular cambia. Endogenous changes in phytohormones were associated with developmental changes during root thickening. Jasmonic acid might be linked to the initial development of tuberous roots. Abscisic acid seemed to be essential for tuber maturation, whereas IAA, cis-zeatin and gibberellin 3 were considered essential for rapid thickening of tuberous roots. A total of 4337 differentially expressed genes (DEGs) were identified during root thickening, including 15 DEGs participated in isoflavonoid biosynthesis, and 153 DEGs involved in starch/sucrose metabolism, hormonal signaling, transcriptional regulation and cell wall metabolism. A hypothetical model of genetic regulation associated with root thickening and isoflavonoid biosynthesis in C. speciosa is proposed, which will help in understanding the underlying mechanisms of tuberous root formation and isoflavonoid biosynthesis.

The R2R3-MYB gene family participates in several plant physiological processes, especially the regulation of the biosynthesis of secondary metabolites. However, little is known about the functions of R2R3-MYB genes in Gynostemma pentaphyllum (G. pentaphyllum), a traditional Chinese medicinal herb that is an excellent source of gypenosides (a class of triterpenoid saponins) and flavonoids. In this study, a systematic genome-wide analysis of the R2R3-MYB gene family was performed using the recently sequenced G. pentaphyllum genome. In total, 87 R2R3-GpMYB genes were identified and subsequently divided into 32 subgroups based on phylogenetic analysis. The analysis was based on conserved exon–intron structures and motif compositions within the same subgroup. Collinearity analysis demonstrated that segmental duplication events were majorly responsible for the expansion of the R2R3-GpMYB gene family, and Ka/Ks analysis indicated that the majority of the duplicated R2R3-GpMYB genes underwent purifying selection. A combination of transcriptome analysis and quantitative reverse transcriptase-PCR (qRT-PCR) confirmed that Gynostemma pentaphyllum myeloblastosis 81 (GpMYB81) along with genes encoding gypenoside and flavonol biosynthetic enzymes exhibited similar expression patterns in different tissues and responses to methyl jasmonate (MeJA). Moreover, GpMYB81 could bind to the promoters of Gynostemma pentaphyllum farnesyl pyrophosphate synthase 1 (GpFPS1) and Gynostemma pentaphyllum chalcone synthase (GpCHS), the key structural genes of gypenoside and flavonol biosynthesis, respectively, and activate their expression. Altogether, this study highlights a novel transcriptional regulatory mechanism that suggests that GpMYB81 acts as a “dual-function” regulator of gypenoside and flavonol biosynthesis in G. pentaphyllum.

Abstract Background Stellera chamaejasme L. is a poisonous plant widely distributes in degraded grasslands in China. The mechanism underlying its spread remains unknown. In some degraded grasslands, S. chamaejasme has gradually replaced previous dominant species, such as Leymus chinensis, Stipa krylovii, Artemisia eriopoda on typical steppes. Apart from its unpalatability by livestock, we hypothesized that the survival strategy (nutrient uptake and water use efficiency) of S. chamaejasme in degraded grasslands could be distinct from other coexisting species in the community. Recently, ecological stoichiometry has been suggested as a new approach for studying the demand for natural resources of plants in a changing world, and the leaf carbon isotopic composition (δ13C leaf) as a rapid and effective high throughput phenotyping method for water use efficiency (WUE), both of which can reveal the survival and adaptive strategies of plants. Therefore, in this study we aimed to fill the knowledge gap concerning ecological stoichiometry in the leaf, stem, and root of S. chamaejasme and its surrounding soil on grasslands with different degrees of degradation, and comparing the leaf nutrient content and δ13C of S. chamaejasme with the coexisting species (L. chinensis, S. krylovii, A. eriopoda) in the communities. Toward this goal, we conducted a field survey in which plants and soils were sampled from four different degraded grasslands on typical steppes in China. Results Our results showed that there is no significant difference of carbon content (C%) and nitrogen content (N%) in leaves of S. chamaejasme in different degraded grasslands, and all element contents and element ratios in stems did not differ significantly. Meanwhile, ecological stoichiometry of S. chamaejasme is distinct from the coexisting species, with low C%, high N% and phosphorus content (P%) in the leaf, indicating high nutrient uptake efficiency of S. chamaejasme in nutrient-poor environments like degraded grasslands. Additionally, S. chamaejasme showed significant higher WUE than other species. Conclusions Our results indicated that high nutrient uptake efficiency and high WUE of S. chamaejasme might together contribute to the spread of S. chamaejasme in degraded grasslands.

Nematode communities are meaningful biological indicators of soil health and soil processes across different grassland types and management practices and analyses of nematode communities provide insight into structure, function, and sensitivity or resilience across multiple ecosystems. In three model grasslands: meadow steppe (MS), typical steppe (TS), and alpine meadow (AM), this current research examined responses of soil nematode communities and related edaphic characteristics to grazing, mowing, and crop cultivation at two soil depths. The research fills a critical knowledge gap by resolving multidirectional influences between local conditions, grassland management practices, and nematode communities. Across grassland types, nematode abundance in AM was greater than MS and TS grasslands, and nematodes were more abundant near the soil surface. Cultivation resulted in greater nematode abundance compared to all other management practices, and generally, bacterivores were the most dominant nematode trophic group. The TS and MS grasslands had relatively more bacterivores, exhibiting substantial influences on soil mineralization and organic matter decomposition pathways. The AM grassland showed relatively more plant feeding nematodes, driving soil mineralization pathways. Among the three management practices, crop cultivation had the greatest impact on nematode community structure and the soil environment, especially in relatively sensitive AM grasslands. In fact, AM soil environments responded most dramatically to cultivation, with nematode abundance, soil quality, and food web complexity increasing. However, soil ecosystem stability, food web reliance, and food web response to resources decreased in cultivated AM soils. Results indicate that unique environmental characteristics in the Qinghai-Tibet plateau drive substantially different AM grassland nematode community structure and soil conditions compared to TS or MS grasslands. As anthropogenic pressures on these ecosystems mount, it is critical to understand how different management practices influence grassland nematode communities, with cascading effects through soil environments.

The degradation of the grassland system has severely threatened the safety of the ecological environment and animal husbandry. The supplement of key substances lost due to degradation is widely used to accelerate the restoration of the degraded grassland ecosystem. In this study, we investigated the effects of biochar and nitrogen addition on soil properties and microorganisms of degraded alpine grassland. The experimental treatments consisted of the control without any addition, only nitrogen addition (10 gN/m2), only biochar addition (4.00 kg/m2 biochar), and the mixed addition of biochar and nitrogen (4.00 kg/m2 biochar and 10 gN/m2 nitrogen, respectively). Adding N alone did not significantly change the pH, total organic carbon (TOC), total nitrogen (TN), microbial biomass (MB), and the composition proportion of microbes of the soil, but increased the contents of soil water content (SWC), NH4+-N, NO3–-N, available phosphorus (AP), and the biomass of bacteria and fungi. The addition of biochar or the mixture of biochar and nitrogen increased the contents of pH, TOC, TN, MB, SWC, NH4+-N, NO3–-N, AP, bacteria, and fungi in the soil and changed the structure of the soil microbial community. The increasing intensity of AP, bacteria, and fungi under the addition of biochar or the mixture of biochar and nitrogen was significantly greater than that under N addition alone. These results indicated that the separated addition of nitrogen and biochar and the mixed addition of biochar and nitrogen all improved the soil condition of the moderate–severe degraded alpine grassland, but the mixed addition of biochar and nitrogen could be a better strategy to remediate the degraded alpine grassland.

Nitrogen(N) addition can significantly improve the aboveground productivity of plants. The responses of reproductive strategies to N addition remain elusive for Leymus chinensis. Here, we examined the vegetative growth and clonal and sexual reproduction of a rhizome clonal grass, Leymus chinensis (Trin.) Tzvel, in response to N addition rates of 0, 2, 4, 8, 16, 32, and 64 g N m−2. N addition altered the reproductive strategy and allometric growth patterns of L. chinensis along the N addition gradient. N addition generally promoted higher investment in the biomass of vegetative and clonal organs, and a lower investment in sexual organs. N addition rates of 16 and 32 g N m−2 were key thresholds; 16 g N m−2 was the optimal rate for sexual reproduction and 32 g N m−2 was optimal for vegetative growth and clonal reproduction. At an addition rate of 16 g N m−2, the sexual reproductive capacity of L. chinensis was highest. Resource allocation to sexual reproduction increased with N addition, but decreased at rates>16 g N m−2. The growth and clonal reproduction of L. chinensis decreased at N concentrations>32 g N m−2. Our findings highlight that the reproductive strategy of L. chinensis varies with N addition rate, and the growth, sexual reproduction, and clonal reproduction strategies of L. chinensis are plastic, which has important implications for production.

With the development of Industry 4.0 and big data technology, the Industrial Internet of Things (IIoT) is hampered by inherent issues such as privacy, security, and fault tolerance, which pose certain challenges to the rapid development of IIoT. Blockchain technology has immutability, decentralization, and autonomy, which can greatly improve the inherent defects of the IIoT. In the traditional blockchain, data is stored in a Merkle tree. As data continues to grow, the scale of proofs used to validate it grows, threatening the efficiency, security, and reliability of blockchain-based IIoT. Accordingly, this paper first analyzes the inefficiency of the traditional blockchain structure in verifying the integrity and correctness of data. To solve this problem, a new Vector Commitment (VC) structure, Partition Vector Commitment (PVC), is proposed by improving the traditional VC structure. Secondly, this paper uses PVC instead of the Merkle tree to store big data generated by IIoT. PVC can improve the efficiency of traditional VC in the process of commitment and opening. Finally, this paper uses PVC to build a blockchain-based IIoT data security storage mechanism and carries out a comparative analysis of experiments. This mechanism can greatly reduce communication loss and maximize the rational use of storage space, which is of great significance for maintaining the security and stability of blockchain-based IIoT. [ABSTRACT FROM AUTHOR]

The aim of this study was to investigate the effects of grazing on soil gross nitrification (GN) and denitrification (DN) rates and soil environmental factors on GN and DN in the desert grassland of northern China. Soil samples were collected from July to November in 2017 and March to June in 2018, with 5-5 soil samples taken from three enclosures (CK) vs. three heavy-grazing (G) randomized treatment blocks. We determined: (1) the soil moisture (SM), pH, bulk density (BD), total nitrogen (TN), soil organic carbon (SOC), and inorganic nitrogen (IN, NH4+-N, and NO3−-N) content, and (2) GN and DN. The relationship between the changes in GN, DN, and the soil environment was analyzed using stepwise multiple-regression analysis. Gross nitrification, DN, pH, BD, C/N, SM, IN, and NO3−-N varied significantly by month. Grazing induced significant increases in SM and NO3− only. GN in the CK treatment was related to NH4+-N and NO3−-N, while GN in the G treatment was related to NH4+-N and SM. DN in the CK treatment was related to NH4+-N, while DN in the G treatment was related to C/N. Additionally, GN and DN had obvious seasonal variations and reached a maximum in July. This highlights the different underlying mechanisms that affect soil GN and DN and the dynamics, particularly in the desert grassland system.

Plant leaf stoichiometry reflects its adaptation to the environment. Leaf stoichiometry variations across different environments have been extensively studied in grassland plants, but little is known about intraspecific leaf stoichiometry, especially for widely distributed species, such as Stellera chamaejasme L. We present the first study on the leaf stoichiometry of S. chamaejasme and evaluate its relationships with environmental variables. S. chamaejasme leaf and soil samples from 29 invaded sites in the two plateaus of distinct environments [the Inner Mongolian Plateau (IM) and Qinghai-Tibet Plateau (QT)] in Northern China were collected. Leaf C, N, P, and K and their stoichiometric ratios, and soil physicochemical properties were determined and compared with climate information from each sampling site. The results showed that mean leaf C, N, P, and K concentrations were 498.60, 19.95, 2.15, and 6.57 g kg−1; the average C:N, C:P, N:P, N:K and K:P ratios were 25.20, 245.57, 9.81, 3.13, and 3.21, respectively. The N:P:K-ratios in S. chamaejasme leaf might imply that its growth is restricted by K- or K+N. Moreover, the soil physicochemical properties in the S. chamaejasme-infested areas varied remarkably, and few significant correlations between S. chamaejasme leaf ecological stoichiometry and soil physicochemical properties were observed. These indicate the nutrient concentrations and stoichiometry of S. chamaejasme tend to be insensitive to variations in the soil nutrient availability, resulting in their broad distributions in China’s grasslands. Besides, different homeostasis strength of the C, N, K, and their ratios in S. chamaejasme leaves across all sites were observed, which means S. chamaejasme could be more conservative in their use of nutrients improving their adaptation to diverse conditions. Moreover, the leaf C and N contents of S. chamaejasm were unaffected by any climate factors. However, the correlation between leaf P content and climate factors was significant only in IM, while the leaf K happened to be significant in QT. Besides, MAP or MAT contribution was stronger in the leaf elements than soil by using mixed effects models, which illustrated once more the relatively weak effect of the soil physicochemical properties on the leaf elements. Finally, partial least squares path modeling suggested that leaf P or K contents were affected by different mechanisms in QT and IM regions, suggesting that S. chamaejasme can adapt to changing environments by adjusting its relationships with the climate or soil factors to improve its survival opportunities in degraded grasslands.

Increasing nitrogen deposition plays a critical role in the material circulation of grassland. Mowing and grazing sheep are important means of utilizing grassland. This study investigated the effects of nitrogen deposition, sheep grazing and mowing on the soil, vegetation and soil microorganisms of grassland. N deposition increased soil inorganic nitrogen, SOM and microbial activity, and decreased soil pH, while grazing sheep and mowing had opposing effects. Compared with mowing, grazing sheep decreased the range of grass groups in the community. N deposition increased the proportion of Leymus chinensis in the community and decreased community diversity. N deposition enhanced the contribution rate of soil to the vegetation community, and reduced the effect of microorganisms on the vegetation community. In addition, N deposition significantly interacted with mowing and grazing sheep in terms of effects on soil inorganic nitrogen, soil organic matter (SOM), microbial respiration (Q), microbial mass carbon (MBC), and vegetation diversity. Therefore, appropriate N deposition in sheep grazing and mown grasslands could enhance inorganic N and organic matter, increase microbial activity, offset the adverse effects of grazing sheep and mowing, and contribute to maintaining community diversity and grassland productivity.

Plant adaptation under climate changes is critical to the maintenance of terrestrial ecosystem structure and function. Studying the response of the endophytic community to climate warming is a novel way to reveal the mechanism of host environmental adaptability because of the prominent role endophytes play in host nutrient acquisition and stress tolerance. However, host performance was generally neglected in previous relevant research, which limits our understanding of the relationships between the endophytic community and host responses to climate warming. The present study selected two plants with different responses to climate warming. Elymus nutans is more suitable for growing in warm environments at low altitude compared to Kobresia pygmaea. K. pygmaea and E. nutans were sampled along an altitude gradient in the natural grassland of Qinghai-Tibet Plateau, China. Root endophytic bacterial and fungal communities were analyzed using high throughput sequencing. The results revealed that hosts growing in more suitable habitats held higher endophytic fungal diversity. Elevation and host identity significantly affected the composition of the root endophytic bacterial and fungal community. 16S rRNA functional prediction demonstrated that hosts that adapted to lower temperatures recruited endophytic communities with higher abundance of genes related to cold resistance. Hosts that were more suitable for warmer and drier environments recruited endophytes with higher abundance of genes associated with nutrient absorption and oxidation resistance. We associated changes in the endophytic community with hosts adaptability to climate warming and suggested a synchronism of endophytic communities and hosts in environmental adaptation.

The R2R3-MYB family is one of the largest plant transcription factor (TF) families playing vital roles in defense, plant growth, and secondary metabolism biosynthesis. Although this gene family has been studied in many species, isoflavonoid biosynthesis-related R2R3-MYB TFs in Callerya speciosa (Champ. ex Benth.) Schot, a traditional Chinese medicinal herb, are poorly understood. Here, a total of 101 R2R3-MYB TFs were identified from C. speciosa transcriptome dataset. 25 clades divided into five functional groups were clustered based on the sequence similarity and phylogenetic tree. Conserved motifs and domain distribution, expression patterns, and coexpression networks were also employed to identify the potential R2R3-MYB TFs in the regulation of isoflavonoid biosynthesis. In silico evaluation showed that the deduced R2R3-CsMYB proteins contain highly conserved R2R3 repeat domain at the N-terminal region, that is the signature motif of R2R3-type MYB TFs. Eight potential TFs (CsMYB17, CsMYB36, CsMYB41, CsMYB44, CsMYB45, CsMYB46, CsMYB72, and CsMYB81) had high degrees of coexpression with four key isoflavonoid biosynthetic genes (CsIFS, CsCHS7, CsHID-1, and CsCHI3), in which CsMYB36 as a potential regulator possessed the highest degree. HPLC analysis showed that formononetin and maackiain contents were significantly increased during the development of tuberous roots, which might be controlled by both related R2R3-CsMYBs and structural genes involved in the isoflavonoid biosynthesis pathway. The transcriptome data were further validated by reverse transcription real-time PCR (RT-qPCR) analysis, and similar expression profiles between TFs and key structural genes were identified. This study was the first step toward the understanding of the R2R3-MYB TFs regulating isoflavonoid biosynthesis in C. speciosa. The results will provide information for further functional analysis and quality improvement through genetic manipulation of these potential R2R3-CsMYB genes in C. speciosa.

Introduction Perioperative infections may be considered predictors of caesarean scar defect (CSD), and multidose antibiotics have a protective effect against CSD. However, the ability of adjunctive azithromycin combined with cephalosporin to reduce the prevalence of CSD remains unclear. The planned study aims to clarify the protective effect of antibiotics against CSD and to assess the effectiveness of adjunctive azithromycin prophylaxis for CSD.Methods and analysis This study is a double-blind, parallel-control randomised clinical trial that will be carried out at the International Peace Maternity and Child Health Hospital. A total of 220 eligible patients will be randomised (1:1) to receive either adjunctive azithromycin or single-dose cephalosporin 30 min before the incision. The evaluation criteria are the prevalence and characteristics of CSD as assessed by transvaginal ultrasound (TVU) and saline infusion sonohysterography (SIS) at 42 days, 6 months and 12 months after delivery. The primary outcome will be the prevalence of CSD, and the characteristics of CSD will be assessed by TVU and SIS 42 days after delivery; all other outcomes are secondary.Ethics and dissemination This protocol received authorisation from the Medical Research Ethics Committee of International Peace Maternity and Child Health Hospital on 25 April 2018 (approval no. GKLW2017-84). The findings will be reported in peer-reviewed publications and presentations at international scientific meetings.Trial registration number ChiCTR-INR-17013272.

The effects of laser scanning speed on the microstructure, microhardness, and corrosion behavior of Ni45 coatings were investigated by using optical microscopy (OM), scanning electron microscopy (SEM), X-ray diffraction (XRD), microhardness, and electrochemical measurements. The results showed that increasing laser scanning speed promotes the transformation from planar crystals to dendrites and refines the grains concurrently. The γ-(Ni, Fe), FeNi3, and M23(C,B)6 are identified as the primary phase composition in the Ni45 coatings regardless of the laser scanning speed. Thereinto, the formation and growth of M23(C,B)6 precipitates can be inhibited with increasing laser scanning speed due to the higher cooling rate, which affects the microhardness distribution and corrosion resistance of the coating. On the one hand, the microhardness of the whole coating presents a downtrend with increasing laser scanning speed due to the reduction of M23(C,B)6 phase. On the other hand, the corrosion resistance in 0.5 M NaCl solution is improved to some extent at higher laser scanning speed because the less precipitation of M23(C,B)6 reduces the depletion of Cr around the precipitates. In contrast, all the coatings exhibit undifferentiated but poor corrosion resistance in the highly corrosive 0.5 M NaCl + 0.5 M H2SO4 solution.

Allelopathy is an important process in plant communities. The effects of allelopathy on seed germination and seedling development have been extensively investigated. However, the influences of extract soaking time and concentration on the foregoing parameters are poorly understood. Here, we conducted a seed germination assay to determine the allelopathic effects of the donor herbs Achnatherum splendens (Trin.) Nevski, Artemisia frigida Willd., and Stellera chamaejasme L., from a degraded grassland ecosystem in northern China, on lettuce (Lactuca sativa L.) seed germination and early seedling growth. Extract soaking times (12 h or 24 h) did not exhibit significantly different effects on lettuce seed germination or seedling development. However, all aqueous herb extracts inhibited lettuce seed germination and root length (RI < 0) and promoted lettuce shoot length, stem length, leaf length, and leaf width (RI > 0) at both low (0.005 g mL−1) and high (0.05 g mL−1) concentrations. Moreover, A. splendens extracts increased seedling biomass (RI > 0) and synthetical allelopathic effect (SE > 0) at both concentrations. In contrast, both A. frigida and S. chamaejasme extracts had hormesis effects, which stimulate at low concentrations (RI > 0) but inhibit at high concentrations (RI < 0) on seedling biomass and synthetical allelopathic effect (SE). The results suggest that allelopathic potential may be an important mechanism driving the dominance of A. frigida and S. chamaejasme in degraded grasslands. Reseeding allelopathy-promoting species such as A. splendens may be beneficial to grassland restoration. The present study also demonstrated that seedling biomass, root and shoot length, and seed germination rate are the optimal bioindicators in allelopathy assays and could be more representative when they are combined with the results of multivariate analyses.

Abstract Background Forage nutritive value plays an important role in livestock nutrition and maintaining sustainable grassland ecosystems, and grazing management can affect the quality of forage. In this study, we investigated the effects of different grazing intensities on the nutritive values of Leymus chinensis (Trin.) Tzvelev, Artemisia spp. and Carex duriuscula C. A. Mey in the steppes of China during the growing seasons from 2011 to 2013. Five grazing management treatments were implemented: (1) rest grazing in spring, heavy grazing in summer and moderate grazing in autumn (RHM), (2) rest grazing in spring, moderate grazing in summer and heavy grazing in autumn (RMH), (3) heavy grazing though all seasons (HHH), (4) heavy grazing in spring and summer and moderate grazing in autumn (HHM) and (5) continuous moderate grazing in all seasons (MMM). Results There were significant effects of year, season, treatment, and year × season and year × treatment interactions only on the crude protein of L. chinensis (P 0.05) for ether extract, neutral detergent fiber, acid detergent fiber and Ca concentration for any of the grasses in spring and summer from 2011 to 2013 under the different grazing management treatments. Conclusions The nutritive value of L. chinensis was more responsive to grazing disturbance than Artemisia spp. and C. duriuscula, and heavy grazing maintained a relatively high crude protein content in all species. Seasonal and interannual seasonal differences in grazing management combinations were two of the most important factors in determining the variability of forage nutritive value, including crude protein, ether extract, neutral detergent fiber, acid detergent fiber and calcium, for L. chinensis, Artemisia spp. and C. duriuscula. We suggest that moderate grazing should be adopted to ensure the quality and yield of forage and promote the sustainable development of animal husbandry.