Multiomics Analyses Provide New Insight into Genetic Variation of Reproductive Adaptability in Tibetan Sheep.

Domestication and artificial selection during production-oriented breeding have greatly shaped the level of genomic variability in sheep. However, the genetic variation associated with increased reproduction remains elusive. Here, two groups of samples from consecutively monotocous and polytocous sheep were collected for genome-wide association, transcriptomic, proteomic, and metabolomic analyses to explore the genetic variation in fecundity in Tibetan sheep. Genome-wide association study revealed strong associations between BMPR1B (p.Q249R) and litter size, as well as between PAPPA and lambing interval; these findings were validated in 1,130 individuals. Furthermore, we constructed the first single-cell atlas of Tibetan sheep ovary tissues and identified a specific mural granulosa cell subtype with PAPPA-specific expression and differential expression of BMPR1B between the two groups. Bulk RNA-seq indicated that BMPR1B and PAPPA expressions were similar between the two groups of sheep. 3D protein structure prediction and coimmunoprecipitation analysis indicated that mutation and mutually exclusive exons of BMPR1B are the main mechanisms for prolific Tibetan sheep. We propose that PAPPA is a key gene for stimulating ovarian follicular growth and development, and steroidogenesis. Our work reveals the genetic variation in reproductive performance in Tibetan sheep, providing insights and valuable genetic resources for the discovery of genes and regulatory mechanisms that improve reproductive success.

Unusual Janus Bi2TeSe2 Topological Insulators Displaying Second-Harmonic Generation, Linear-in-Temperature Resistivity, and Weak Antilocalization.

Well-established knowledge about inversion-symmetric Bi2TexSe3-x topological insulators characterizes the promising new-generation quantum device. Noticeably, the inversion asymmetric phase containing different surface electronic structures may create an extra topological phenomenon pointing to a new device paradigm. Herein, Janus Bi2TeSe2 single-crystal nanosheets with an unconventional stacking sequence of Se-Bi-Se-Bi-Te are realized via chemical vapor deposition growth, which is clarified by atomically resolved AC-STEM and elemental mapping. An obvious polarization-dependent second-harmonic generation with a representative 6-fold rotational symmetry is detected due to the broken out-of-plane mirror symmetry in this system. Low-temperature transport measurements display a strange metal-like linear-in-temperature resistivity. Anomalous conductance peaks under low magnetic fields induced by the weak antilocalization effect of topological surface states and the two-dimensional transport-dominated anisotropic magnetoresistance are revealed. These findings correlate the Janus Bi2TeSe2 phase with emerging physics topics, which would inspire fresh thoughts in well-developed Bi3TexSe3-x topological insulators and open up opportunities for exploring hybrid nonlinear optoelectronic topological devices.

A model of hybrid speciation process drawn from three new poplar species originating from distant hybridization between sections.

Although numerous studies have been conducted on hybrid speciation, our understanding of this process remains limited. Through an 18-year systematic investigation of all taxa of Populus on the Qinghai-Tibet Plateau, we discovered three new taxa with clear characteristics of sect. Leucoides. Further evidence was gathered from morphology, whole-genome bioinformatics, biogeography, and breeding to demonstrate synthetically that they all originated from distant hybridization between sect. Leucoides and sect. Tacamahaca. P. gonggaensis originated from the hybridization of P. lasiocarpa with P. cathayana, P. butuoensis from the hybridization of P. wilsonii with P. szechuanica, and P. dafengensis from the hybridization of P. lasiocarpa with P. szechuanica. Due to heterosis, the three hybrid taxa possess greater ecological adaptability than their ancestral species. We propose a hybrid speciation process model that incorporates orthogonal, reverse, and backcrossing events. This model can adequately explain some crucial evolutionary concerns, such as the nuclear-cytoplasmic conflict on phylogeny and the extinction of ancestral species within the distribution range of hybrid species.

A new species of Populus and the extensive hybrid speciation arising from it on the Qinghai-Tibet Plateau.

While the diversity of species formation is broadly acknowledged, significant debate exists regarding the universal nature of hybrid species formation. Through an 18-year comprehensive study of all Populus species on the Qinghai-Tibet Plateau, 23 previously recorded species and 8 new species were identified. Based on morphological characteristics, these can be classified into three groups: species in section Leucoides, species with large leaves, and species with small leaves in section Tacamahaca. By conducting whole-genome re-sequencing of 150 genotypes from these 31 species, 2.28 million single nucleotide polymorphisms (SNPs) were identified. Phylogenetic analysis utilizing these SNPs not only revealed a highly intricate evolutionary network within the large-leaf species of section Tacamahaca but also confirmed that a new species, P. curviserrata, naturally hybridized with P. cathayana, P. szechuanica, and P. ciliata, resulting in 11 hybrid species. These findings indicate the widespread occurrence of hybrid species formation within this genus, with hybridization serving as a key evolutionary mechanism for Populus on the plateau. A novel hypothesis, "Hybrid Species Exterminating Their Ancestral Species (HSEAS)," is introduced to explain the mechanisms of hybrid species formation at three different scales: the entire plateau, the southeastern mountain region, and individual river valleys.

To Accelerate the Process of Brain Death Determination in China Through the Strategy and Practice of Establishing Demonstration Hospitals.

BACKGROUND: Our objective was to explore whether a brain death determination (BDD) strategy with demonstration hospitals can accelerate the process of BDD in China. METHODS: We proposed the construction standards for the BDD quality control demonstration hospitals (BDDHs). The quality and quantity of BDD cases were then analyzed. RESULTS: A total of 107 BDDHs were established from 2013 to 2022 covering 29 provinces, autonomous regions, and municipalities under jurisdiction of the central government of the Chinese mainland (except Qinghai and Tibet). A total of 1,948 professional and technical personnel from these 107 BDDHs received training in BDD, 107 quality control personnel were trained in the quality control management of BDD, and 1,293 instruments for electroencephalography, short-latency somatosensory evoked potential recordings, and transcranial Doppler imaging were provided for BDD. A total of 6,735 BDD cases were submitted to the quality control center. Among the nine quality control indicators for BDD in these cases, the implementation rate, completion rate, and coincidence rate of apnea testing increased the most, reaching 99%. CONCLUSIONS: The strategy of constructing BDDHs to promote BDD is feasible and reliable. Ensuring quality and quantity is a fundamental element for the rapid and orderly popularization of BDD in China.

Nonsaturating Linear Magnetoresistance Manifesting Two-Dimensional Transport in Wet-Chemical Patternable Bi2O2Te Thin Films.

Two-dimensional (2D) materials with exotic transport behaviors have attracted extensive interest in microelectronics and condensed matter physics, while scaled-up 2D thin films compatible with the efficient wet-chemical etching process represent realistic advancement toward new-generation integrated functional devices. Here, thickness-controllable growth and chemical patterning of high-quality Bi2O2Te continuous films are demonstrated. Noticeably, except for an ultrahigh mobility (∼45074 cm2 V-1 s-1 at 2 K) and obvious Shubnikov-de Hass quantum oscillations, a 2D transport channel and large linear magnetoresistance are revealed in the patterned Bi2O2Te films. Investigation implies that the linear magnetoresistance correlates with the inhomogeneity described by P. B. Littlewood's theory and EMT-RRN theory developed recently. These results not only reveal the nonsaturating linear magnetoresistance in high-quality Bi2O2Te but shed light on understanding the corresponding physical origin of linear magnetoresistance in 2D high-mobility semiconductors and providing a pathway for the potential application in multifunctional electronic devices.

Physiological, metabolomic, and transcriptomic reveal metabolic pathway alterations in Gymnocypris przewalskii due to cold exposure.

Teleost fish have evolved various adaptations that allow them to tolerate cold water conditions. However, the underlying mechanism of this adaptation is poorly understood in Tibetan Plateau fish. RNA-seq combined with liquid chromatography‒mass spectrometry (LC‒MS/MS) metabolomics was used to investigate the physiological responses of a Tibetan Plateau-specific teleost, Gymnocypris przewalskii, under cold conditions. The 8-month G. przewalskii juvenile fish were exposed to cold (4 ℃, cold acclimation, CA) and warm (17 ℃, normal temperature, NT) temperature water for 15 days. Then, the transcript profiles of eight tissues, including the brain, gill, heart, intestine, hepatopancreas, kidney, muscle, and skin, were evaluated by transcriptome sequencing. The metabolites of the intestine, hepatopancreas, and muscle were identified by LC‒MS/MS. A total of 5,745 differentially expressed genes (DEGs) were obtained in the CA group. The key DEGs were annotated using Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analysis. The DEGs from the eight tissues were significantly enriched in spliceosome pathways, indicating that activated alternative splicing is a critical biological process that occurs in the tissues to help fish cope with cold stress. Additionally, 82, 97, and 66 differentially expressed metabolites were identified in the intestine, hepatopancreas, and muscle, respectively. Glutathione metabolism was the only overlapping significant pathway between the transcriptome and metabolome analyses in these three tissues, indicating that an activated antioxidative process was triggered during cold stress. In combination with the multitissue transcriptome and metabolome, we established a physiology-gene‒metabolite interaction network related to energy metabolism during cold stress and found that gluconeogenesis and long-chain fatty acid metabolism played critical roles in glucose homeostasis and energy supply.

Two-Dimensional Superconductivity in Air-Stable Single-Crystal Few-Layer Bi3O2S3.

The progress of unconventional superconductors at the two-dimensional (2D) limit has inspired much interest. Recently, a new superconducting system was discovered in the semimetallic ternary Bi-O-S family. However, pure-phase crystals are difficult to synthesize because of the complicated stacking sequence of multiple charged layers and similar formation kinetics among ternary polytypes, leaving several fundamental issues regarding the structure-superconductivity correlation unresolved. Herein, 2D single-crystal ultrathin Bi3O2S3 nanosheets are prepared by using low-pressure chemical vapor deposition, and their atomic arrangement is clarified. Magnetotransport measurements indicate a superconducting transition at ∼6.1 K that is thickness-independent. The transport results demonstrate 2D superconducting characteristics, such as the Berezinskii-Kosterlitz-Thouless transition, and strong anisotropy with magnetic field orientations following the 2D Tinkham formula. The difference from superconductivity of powder is demonstrated from the perspective of their corresponding microstructures. These results corroborate the superconducting behavior of Bi3O2S3, providing fresh insights into the search for other bismuth oxychalcogenides and derivative BiS2-based analogues at the 2D limit.

Effects of the SPI/lncRNA NEAT1 Axis on Functions of Trophoblast and Decidual Cells in Patients with Recurrent Miscarriage.

Recurrent miscarriage (RM) is a frustrating and complex pregnancy disorder and long noncoding RNAs (lncRNAs) modulate susceptibility to RM. This study expounded on the role of specificity protein 1 (SP1) in functions of chorionic trophoblast and decidual cells via regulating lncRNA nuclear paraspeckle assembly transcript 1 (NEAT1). Chorionic villus tissues and decidual tissues of RM patients and normal pregnant women were collected. Real-time quantitative polymerase chain reaction and Western blotting revealed that SP1 and NEAT1 were downregulated in trophoblast and decidual tissues of RM patients, and the Pearson correlation analysis detected that they were positively correlated in expression level. Chorionic trophoblast and decidual cells of RM patients were isolated and intervened by vectors over-expressing SP1 or NEAT1 siRNAs. Thereafter, the cell counting kit-8, Transwell, flow cytometry assays detected that SP1 overexpression accelerated trophoblast cell proliferation, invasion, and migration, meanwhile, enhancing decidual cell proliferation while repressed apoptosis. Next, the dual-luciferase and Chromatin immunoprecipitation assays showed that SP1 bound to the NEAT1 promoter region and further activated NEAT1 transcription. Silencing NEAT1 reversed the efforts of SP1 overexpression on the functions of trophoblast and decidual cells. Overall, SP1 activated NEAT1 transcription, accelerating trophoblast cell proliferation, invasion, and migration and mitigating decidual cell apoptosis.

Air pollution associated with incidence and progression trajectory of chronic lung diseases: a population-based cohort study.

BACKGROUND: No prior study has examined the effects of air pollution on the progression from healthy to chronic lung disease, subsequent chronic lung multimorbidity and further to death. METHODS: We used data from the UK Biobank of 265 506 adults free of chronic lung disease at recruitment. Chronic lung multimorbidity was defined as the coexistence of at least two chronic lung diseases, including asthma, chronic obstructive pulmonary disease and lung cancer. The concentrations of air pollutants were estimated using land-use regression models. Multistate models were applied to assess the effect of air pollution on the progression of chronic lung multimorbidity. RESULTS: During a median follow-up of 11.9 years, 13 863 participants developed at least one chronic lung disease, 1055 developed chronic lung multimorbidity and 12 772 died. We observed differential associations of air pollution with different trajectories of chronic lung multimorbidity. Fine particulate matter showed the strongest association with all five transitions, with HRs (95% CI) per 5 µg/m3 increase of 1.31 (1.22 to 1.42) and 1.27 (1.01 to 1.57) for transitions from healthy to incident chronic lung disease and from incident chronic lung disease to chronic lung multimorbidity, and 1.32 (1.21 to 1.45), 1.24 (1.01 to 1.53) and 1.91 (1.14 to 3.20) for mortality risk from healthy, incident chronic lung disease and chronic lung multimorbidity, respectively. CONCLUSION: Our study provides the first evidence that ambient air pollution could affect the progression from free of chronic lung disease to incident chronic lung disease, chronic lung multimorbidity and death.

Poly(ethylene oxide) Concentration Gradient-Based Microfluidic Isolation of Circulating Tumor Cells.

Circulating tumor cells (CTCs) have emerged as promising circulating biomarkers for non-invasive cancer diagnosis and management. Isolation and detection of CTCs in clinical samples are challenging due to the extreme rarity and high heterogeneity of CTCs. Here, we describe a poly(ethylene oxide) (PEO) concentration gradient-based microfluidic method for rapid, label-free, highly efficient isolation of CTCs directly from whole blood samples. Stable concentration gradients of PEO were formed within the microchannel by co-injecting the side fluid (blood sample spiked with 0.025% PEO) and center fluid (0.075% PEO solution). The competition between the elastic lift force and the inertial lift force enabled size-based separation of large CTCs and small blood cells based on their distinct migration patterns. The microfluidic device could process 1 mL of blood sample in 30 min, with a separation efficiency of >90% and an enrichment ratio of >700 for tumor cells. The isolated CTCs from blood samples were enumerated by immunofluorescence staining, allowing for discrimination of breast cancer patients from healthy donors with an accuracy of 84.2%. The concentration gradient-based microfluidic separation provides a powerful tool for label-free isolation of CTCs for a wide range of clinical applications.

The Interaction in Electrolyte Additives Accelerates Ion Transport to Achieve High-Energy Non-Aqueous Lithium Metal Batteries.

Electrolyte engineering is a feasible strategy to realize high energy density lithium metal batteries. However, stabilizing both lithium metal anodes and nickel-rich layered cathodes is extremely challenging. To break through this bottleneck, a dual-additives electrolyte containing fluoroethylene carbonate (10 vol.%) and 1-methoxy-2-propylamine (1 vol.%) in conventional LiPF6 -containing carbonate-based electrolyte is reported. The two additives can polymerize and thus generate dense and uniform LiF and Li3 N-containing interphases on both electrodes' surfaces. Such robust ionic conductive interphases not only prevent lithium dendrite formation in lithium metal anode but also suppress stress-corrosion cracking and phase transformation in nickel-rich layered cathode. The advanced electrolyte enables Li||LiNi0.8 Co0.1 Mn0.1 O2 stably cycle for 80 cycles at 60 mA g-1 with a specific discharge capacity retention of 91.2% under harsh conditions.

d- and p-Block single-atom catalysts supported by BN nanocages toward electrochemical reactions of N2 and O2.

Electrocatalysis is involved in many energy storage and conversion devices, triggering research and development of electrocatalysts, particularly single-atom catalysts (SACs). The introduction of the strain effect to enhance the performance of SACs has drawn ever-increasing research attention, which can tailor the local atomic and electronic structure of active sites. Herein, via high throughput calculations, we have explored the effects of strain on the catalytic performance of SACs with MN4 configuration for electrochemical reactions of N2 and O2 by incorporating d- and p-block single metal atoms into BN nanocages (BNNCs). The calculations demonstrate that Os@BNNC exhibits the highest catalytic activity for the nitrogen reduction reaction (NRR) with a limiting potential of -0.29 V. Co@BNNC can serve as an excellent bifunctional SAC for the oxygen reduction reaction (ORR) and oxygen evolution reaction (OER), with overpotentials of 0.32 and 0.37 V, respectively. In particular, Sn@BNNC with a p-block metal as the active center is a competitive SAC for the ORR with an overpotential of 0.64 V. More interestingly, the NRR and ORR performances of SACs supported by BNNCs have a close correlation with the structural and electronic properties of adsorbed N2 and O2 molecules, which proves that controlling the adsorption energy of N2 and O2 molecules is crucial to improving the catalytic activity of BNNC. The current investigation opens up an avenue for designing SACs embedded in nanocages possessing intrinsically curved surfaces for electrochemical reactions.

Independent and joint trajectories of depression and anxiety symptoms among Chinese male sailors throughout a prolonged non-24-h rotating shift schedule at sea: a parallel-process growth mixture modeling approach.

BACKGROUND: The predictive and protective effect of hardiness on mental health remains unclear among shift workers on non-24-h working schedules. The present study aimed to investigate the independent and joint trajectories of depression and anxiety symptoms and the role of hardiness during a prolonged period of non-24-h shift working schedule. METHODS: Four hundred nine Chinese male sailors (working on 18-h watchstanding schedule) were recruited and completed all 5-wave tests through online questionnaires (at Day 1, 14, 28, 42, 55, respectively) during a 55-day sailing. The questionnaires included sociodemographic variables, hardiness, depression and anxiety symptoms. Independent and joint trajectories of depression and anxiety symptoms were estimated by latent growth mixture models. The effect of hardiness on trajectories was examined by logistic regression models. RESULTS: 2 and 3 latent trajectories were identified for depression and anxiety symptoms, respectively. Based on initial levels and development trends, 3 distinct joint trajectories of depression and anxiety were identifed and named as: "Low-Inverted U" group (73.6%), "Moderate-Deterioration" group (6.9%), and "High-Stable" group (9.5%). Sailors with higher levels of hardiness were more likely to follow the "Low-Inverted U" trajectory of depression and anxiety symptoms (all p < 0.001). CONCLUSIONS: There existed individual differences in the trajectories of depression and anxiety. Hardiness may have a protective effect that can prevent and alleviate depression and anxiety symptoms. Therefore, hardiness-based intervention programs are encouraged among the shift workers on non-24-h working and rest schedules.

Plant-based natural flavonoids show strong inhibition of aflatoxin production and related gene expressions correlated with chemical structure.

Aflatoxins are strong carcinogenic and mutagenic fungal metabolites, and aflatoxin contamination is a critical issue in agriculture and food production. Natural flavonoids can suppress aflatoxin biosynthesis; however, the structure-activity relationship remains unclear. In the present study, a total of 36 structurally related natural flavonoids were tested against the aflatoxigenic Aspergillus flavus, both in-vitro and in-situ (on maize kernels), to investigate their structure-activity relationship and biological activity. Aflatoxin production (IC50 values: 10.85-20.09 µg/mL) and the expression of related genes (aflD, aflK, aflQ, and aflR) were found to be strongly inhibited. Structure-activity relationship studies revealed that the [-OH] or [-O-CH3] groups at position 6 of ring A and position 4' of ring B were closely associated with antifungal and antiaflatoxigenic activities. These findings provide valuable information for the development of clean and safe methods to prevent aflatoxin contamination in food.

Air pollution and stroke hospitalization in the Beibu Gulf Region of China: A case-crossover analysis.

BACKGROUND: The relationship between air pollution and stroke has been extensively studied, however, the evidence regarding the association between air pollution and hospitalization due to stroke and its subtypes in coastal areas of China is limited. OBJECTIVE: To estimate the associations between air pollution and hospitalizations of stroke and its subtypes in the Beibu Gulf Region of China. METHODS: We conducted a time-stratified case-crossover study in 15 cities in Beibu Gulf Region in China from 2013 to 2016. Exposures to PM1, PM2.5, PM10, SO2, NO2, O3, and CO on the case and control days were assessed at residential addresses using bilinear interpolation. Conditional logistic regressions were constructed to estimate city-specific associations adjusting for meteorological factors and public holidays. Meta-analysis was further conducted to pool all city-level estimates. RESULTS: There were 271,394 case days and 922,305 control days. The odds ratios (ORs) for stroke hospitalizations associated with each interquartile range (IQR) increase in 2-day averages of SO2 (IQR: 10.8 µg/m3), NO2 (IQR: 11.2 µg/m3), and PM10 (IQR: 37 µg/m3) were 1.047 (95 % CI [confidence interval]: 1.015-1.080), 1.040 (95 % CI: 1.027-1.053), and 1.018 (95 % CI: 1.004-1.033), respectively. The associations with hospitalizations of ischemic stroke were significant for all seven pollutants, while the association with hemorrhagic stroke was significant only for CO. The associations of SO2, NO2, and O3 with stroke hospitalization were significantly stronger in the cool season. CONCLUSIONS: Short-term increase in SO2, NO2, and PM10 might be important triggers of stroke hospitalization. All seven air pollutants were associated with ischemic stroke hospitalization, while only CO was associated with hemorrhagic stroke hospitalization. These results should be considered in public health policy.

Sex-specific metabolic dysregulation in digestive glands of green mussels following exposure to triazophos.

As a ubiquitous environmental pollutant in China, triazophos (TP) is known to have neurotoxicity, oxidative stress, and reproductive toxicity to mussels. To investigate the molecular mechanisms of TP toxicity, metabolic changes in the digestive glands of Perna viridis in different sexes were examined after treated with 35 µg/L TP. Notably, 158 significant different metabolites (SDMs) were detected in TP-treated mussels and more than half of the SDMs were lipids and lipid-like molecules, which suggested that TP disturbed the lipid metabolism of P. viridis. In addition, metabolites associated with neurotoxicity and reproductive disturbance were also detected in female and male mussels. Moreover, a larger number of SDMs were found in male mussels (120 SDMs) than females (99 SDMs), and 60 common metabolites exhibited consistent variation tendency and similar magnitude in both sexes. The metabolic alternations in female and male mussels displayed similar protective mechanisms and also sex-specific responses, male mussels were more sensitive to TP exposure. This research provided new data about the molecular mechanisms of TP toxicity and the gender specific changes in mussels after treated by chemicals.

Tunable Mechanics and Micromechanism in Close-Knit Silicide-in-SiO2 Core-Shell Nanowires.

Bending/tension mechanics is one of the core issues for nanowires in flexible free-standing transport and sensor applications, but it remains a challenge to tailor the mechanical performance beyond the inherent properties. Herein, based on structure engineering, silicon-based Mn5Si3@SiO2 nanocables are proposed and demonstrated as versatile nanosystems. Except for outstanding toughness, large ultimate strain, and great strength, they display diverse mechanical behaviors such as simplex elasticity, plasticity, and viscoelasticity under different external conditions. The tunable performances originate from synergetic effects between the core and shell components, like the atomic bonding transitional interface and space confinement, which induce optimizing internal stress distribution and the dislocation evolution mechanism in the core. The related mechanical performance is revealed carefully. The bending and tension dynamic picture, quantitative force curve, stress-strain dependence, and the corresponding lattice evolution are acquired by in/ex situ characterizations and measurements. These results contribute to nanowire mechanical design and also expand to strain-regulated three-dimensional multifunctional nanosystems.

Fatty acid metabolism and antioxidant capacity in Gymnocypris przewalskii (Kessler, 1876) response to thermal stress.

The Qinghai-Tibet Plateau is undergoing a wet-warming transition, which could affect the survival of the native fish. However, the tolerance and physiological response to thermal stress is rarely studied in Gymnocypris przewalskii, a rare native fish in the Tibetan plateau. In this study, first, we detected the thermal tolerance of five groups of six-month G. przewalskii which acclimated at 8, 12, 16, 20, and 24 °C for two weeks, respectively, by critical thermal methodology. Then, through heat challenge, we detected the metabolites, key enzyme activities, and gene expressions involved in metabolism and antioxidant in the hepatopancreas when the temperatures increased from 16 °C to 18, 20, 22, 24, 26, and 28 °C for 12 h, respectively. The results showed that although the fish are sensitive to high temperatures, the quick acclimation at mild high temperatures could significantly improve the tolerance to acute high-temperature stress in juvenile G. przewalskii. During the heat challenge study, blood glucose significantly increased at heat stress (P < 0.05). At the same time, total cholesterol (TC), triglyceride (TG), and free fatty acid (FFA) significantly decreased when the temperature rose continuously to 20 °C. Metabolic enzyme activities of carnitine palmityl transferase I (CPT-Ⅰ), acetyl-CoA carboxylase (ACC), and fatty acid synthase (FAS) significantly decreased at 20 °C (P < 0.05). Superoxide dismutase (SOD) and antioxidant capacity (T-AOC) significantly increased at 20 °C (P < 0.05). The relative transcript levels of genes involved in antioxidant and glycolysis/gluconeogenesis were markedly higher than the control at 20-26 °C (P < 0.05). The genes involved in fatty acid biosynthesis or metabolism showed different expression patterns under heat stress. Heat shock protein 70 (Hsp70) and Hsp90 were significantly higher than the control at 18 °C and 26 °C, respectively. These results confirmed the prediction that G. przewalskii is sensitive to high temperatures, so conservation efforts should pay more attention to the warming damage.

Insight into the microbial mechanisms for the improvement of spent mushroom substrate composting efficiency driven by phosphate-solubilizing Bacillus subtilis.

The objective of this study was to investigate the microbial mechanisms for the improvement of composting efficiency after Bacillus subtilis inoculation with soluble phosphorus function in the spent mushroom substrate (SMS) aerobic composting. The methods in this study, including redundant analysis (RDA), co-occurrence network analyze and Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSt 2) were carried out studying the dynamic changes of phosphorus (P) components, microbial interactions and metabolic characteristics in the SMS aerobic composting inoculated with phosphorus-solubilizing B. subtilis (PSB). An increase in germination index (GI) (up to 88.4%), total nitrogen (TN) (16.6 g kg-1), available P content (0.34 g kg-1) and total P (TP) content (3.20 g kg-1) and a decrease in total organic carbon (TOC), C/N and electrical conductivity (EC) in final composting stage indicated B. subtilis inoculation could further improve maturity quality of the composting product compared with CK. Other results also demonstrated that PSB inoculation increased the stability of compost, humification degree and bacterial diversity, contributing to P fractions transformation in the composting process. Co-occurrence analysis suggested that PSB strengthened microbial interactions. Metabolic function of bacterial community analysis showed pathways such as carbohydrate metabolism, and amino acid metabolism in the composting were increased by effects of PSB inoculation. In summary, this study reveals a useful basis for better regulating the P nutrient level of the SMS composting and reducing environmental risks by inoculating B. subtilis with P solubilizing function.