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Abstract The frigid and droughty climate of Xinjiang in China has given rise to unique indigenous sheep breeds with robust adaptability and resistance. To investigate the genetic mechanism of adaptability of Xinjiang sheep to the local extreme environment, we conducted population genetic structure analyses for three native Xinjiang sheep breeds: Altay sheep (ALT), Bashbay Sheep (BSBC), and Duolang sheep (DLC), as well as two foreign sheep breeds: Suffolk and Dorset, using the Ovine Infinium HD SNP BeadChip(680 K). Our findings revealed distinct genetic and evolutionary histories between Xinjiang and foreign sheep breeds. Principal Component Analysis (PCA) and phylogenetic tree effectively differentiate these five sheep breeds based on their geographical origins, and the domestication level of Xinjiang sheep is comparatively lower than that of foreign sheep breeds. Furthermore, by utilizing three selective signature methods, namely Fixation Index (Fst), Cross Population Extended Haplotype Homozygosity Test (XP-EHH), and Nucleotide Diversity (π), we have successfully identified 22 potential candidate genes. Among these genes, there are TBXT, PDGFD, and VEGFA, which are closely related to tail type and lipid metabolism; VIL1, SLC11A1, and ZBTB46, which are associated with immune function; and candidate genes such as BNC1, HDAC1, and BMP5, which impact sheep reproductive traits. This study establishes a foundation for conserving and utilizing local sheep germplasm resources in Xinjiang and provides molecular insights into the genetic mechanisms governing sheep adaptation to extreme cold and arid environments.

Abstract Lithography technology is a powerful tool for preparing complex microstructures through projecting patterns from static templates with permanent features onto samples. To simplify fabrication and alignment processes, dynamic photomask for multiple configurations preparation becomes increasingly noteworthy. Hereby, we report a dynamic photomask by assembling the electrically stimulated nematic liquid crystal (NLC) into multifarious architectures. This results in reconfigurable and switchable diffraction patterns due to the hybrid phase arising from the NLC molecular orientations. These diffraction patterns are adopted as metamask to produce multiple microstructures with height gradients in one-step exposure and hierarchical microstructures through multiple in-situ exposures using standard photolithography. The fabricated pattern has feature size about 3.2 times smaller than the electrode pattern and can be transferred onto silicon wafer. This strategy can be extended to design diverse microstructures with great flexibility and controllability, offers a promising avenue for fabricating metamaterials via complex structures with simplified lithography processes.

The balanced gut microbiota in intestinal mucus layer plays an instrumental role in the health of the host. However, the mechanisms by which the host regulates microbial communities in the mucus layer remain largely unknown. Here, we discovered that the host regulates bacterial colonization in the gut mucus layer by producing a protein called Chitinase 3-like protein 1 (Chi3l1). Intestinal epithelial cells are stimulated by the gut microbiota to express Chi3l1. Once expressed, Chi3l1 is secreted into the mucus layer where it interacts with the gut microbiota, specifically through a component of bacterial cell walls called peptidoglycan. This interaction between Chi3l1 and bacteria is beneficial for the colonization of bacteria in the mucus, particularly for Gram-positive bacteria like Lactobacillus. Moreover, a deficiency of Chi3l1 leads to an imbalance in the gut microbiota, which exacerbates colitis induced by dextran sodium sulfate. By performing fecal microbiota transplantation from Villin-cre mice or replenishing Lactobacillus in IEC∆Chil1 mice, we were able to restore their colitis to the same level as that of Villin-cre mice. In summary, this study shows a ‘scaffold model’ for microbiota homeostasis by interaction between intestinal Chi3l1 and bacteria cell wall interaction, and it also highlights that an unbalanced gut microbiota in the intestinal mucus contributes to the development of colitis.

Increasing the number of teats in sheep helps to improve the survival rate of sheep lambs after birth. In order to analyze the candidate genes related to the formation of multiple teats in Hu sheep, the present study was conducted to investigate the genetic pattern of multiple teats in Hu sheep. In this study, based on genome-wide data from 157 Hu sheep, Fst, xp-EHH, Pi and iHS signaling were performed, and the top 5% signal regions of each analyzed result were annotated based on the Oar_v4.0 for sheep. The results show that a total of 142 SNP loci were selected. We found that PTPRG, TMEM117 and LRP1B genes were closely associated with polypodium formation in Hu sheep, in addition, among the candidate genes related to polypodium we found genes such as TMEM117, SLC25A21 and NCKAP5 related to milk traits. The present study screened out candidate genes for the formation of multiple teats at the genomic level in Hu sheep.

Objective By assessing the genetic diversity and associated selective traits of Kirghiz sheep (KIR), we aim to uncover the mechanisms that contribute to sheep’s adaptability to the Pamir Plateau environment. Methods This study utilized Illumina Ovine SNP50 BeadChip data from KIR residing in the Pamir Plateau, Qira Black sheep (QBS) inhabiting the Taklamakan Desert, and commonly introduced breeds including Dorper sheep (DOR), Suffolk sheep (SUF), and Hu sheep (HU). The data was analyzed using principal component analysis, phylogenetic analysis, population admixture analysis, kinship matrix analysis, linkage disequilibrium analysis, and selective signature analysis. We employed four methods for selective signature analysis: fixation index (Fst), cross-population extended homozygosity (XP-EHH), integrated haplotype score (iHS), and nucleotide diversity (Pi). These methods aim to uncover the genetic mechanisms underlying the germplasm resources of Kirghiz sheep, enhance their production traits, and explore their adaptation to challenging environmental conditions. Results The test results unveiled potential selective signals associated with adaptive traits and growth characteristics in sheep under harsh environmental conditions, and annotated the corresponding genes accordingly. These genes encompass various functionalities such as adaptations associated with plateau, cold, and arid environment (ETAA1, UBE3D, TLE4, NXPH1, MAT2B, PPARGC1A, VEGFA, TBX15 and PLXNA4), wool traits (LMO3, TRPS1, EPHA5), body size traits (PLXNA2, EFNA5), reproductive traits (PPP3CA, PDHA2, NTRK2), and immunity (GATA3). Conclusion Our study identified candidate genes associated with the production traits and adaptation to the harsh environment of the Pamir Plateau in Kirghiz sheep. These findings provide valuable resources for local sheep breeding programs. The objective of this study is to offer valuable insights for the sustainable development of the Kirghiz sheep industry.

The objective of this study is to analyze environmental genetic selection signals in large-scale sheep populations with conflicting environmental adaptations, aiming to identify and isolate genes associated with environmental adaptations in sheep populations. Kirghiz sheep, which inhabit high-altitude environments year-round, demonstrate the ability to adapt to extreme conditions. In this study, 42 Kirghiz sheep, 24 Tien-Shan in Kyrgyzstan sheep, 189 Qira black sheep, and 160 Chinese Merino sheep were genotyped using Illumina Ovine SNP50K chip. Regions exhibiting a selection signal threshold of 5%, as well as PI analysis and haplotype statistical scanning gene data were annotated, and intersecting genes were identified as candidate genes. Through Fst and haplotype statistical analysis revealed the key gene PDGFD and its vicinity’s impact on fat deposition in sheep tails. Additionally, Fst and PI analysis uncovered genes related to high-altitude adaptation as well as those linked to animal growth and reproduction.Further GO and KEGG enrichment pathway analyses unveiled pathways associated with high-altitude adaptation such as negative regulation of peptidyl-tyrosine phosphorylation and xenobiotic metabolism processes.This investigation into the adaptability of Kirghiz sheep provides theoretical support and practical guidance for the conservation and genetic enhancement of Kirghiz sheep germplasm resources.

Abstract Sodium layered oxide with anion redox activity (SLO‐A) stands out as a promising cathode material for sodium‐ion batteries due to its impressive capacity and high voltage resulting from Mn‐ and O‐redox processes. However, the SLO‐A faces significant challenges in cycling stability and rate performance, primarily due to the poor reversibility and sluggish kinetics of the O‐redox. In this study,a novel Ti‐doped material, Na2/3Li2/9Mn53/72Ti1/24O2 (NLMTO), exhibiting remarkable characteristics such as a notable rate capacity (130 mAh g−1 at 3C, where 1C equals 200 mA g−1) and excellent cycling retention (85.4% after 100 cycles at 0.5C) is introduced. Employing electrochemical differential analyses, the contributions to the superior performance arising from the Mn‐ and O‐redox processes are quantitatively delineated. The optimized performance of NLMTO is attributed, in part, to the enhanced stability of both bulk and interface structures. The introduction of Ti through substitution not only contributes to this stability but also allows for the fine‐tuning of the material's electron configurations. This is achieved by augmenting the density of states near the Fermi energy level, as well as elevating the O 2p and Mn 3d orbits. This research advances sodium‐ion battery technology.

Abstract Enhancing both the number of active sites available and the intrinsic activity of Co‐based electrocatalysts simultaneously is a desirable goal. Herein, a ZIF‐67‐derived hierarchical porous cobalt sulfide decorated by Au nanoparticles (NPs) (denoted as HP‐Au@CoxSy@ZIF‐67) hybrid is synthesized by low‐temperature sulfuration treatment. The well‐defined macroporous–mesoporous–microporous structure is obtained based on the combination of polystyrene spheres, as‐formed CoxSy nanosheets, and ZIF‐67 frameworks. This novel three‐dimensional hierarchical structure significantly enlarges the three‐phase interfaces, accelerating the mass transfer and exposing the active centers for oxygen evolution reaction. The electronic structure of Co is modulated by Au through charge transfer, and a series of experiments, together with theoretical analysis, is performed to ascertain the electronic modulation of Co by Au. Meanwhile, HP‐Au@CoxSy@ZIF‐67 catalysts with different amounts of Au were synthesized, wherein Au and NaBH4 reductant result in an interesting “competition effect” to regulate the relative ratio of Co2+/Co3+, and moderate Au assists the electrochemical performance to reach the highest value. Consequently, the optimized HP‐Au@CoxSy@ZIF‐67 exhibits a low overpotential of 340 mV at 10 mA cm–2 and a Tafel slope of 42 mV dec–1 for OER in 0.1 M aqueous KOH, enabling efficient water splitting and Zn–air battery performance. The work here highlights the pivotal roles of both microstructural and electronic modulation in enhancing electrocatalytic activity and presents a feasible strategy for designing and optimizing advanced electrocatalysts.

The Grignard-type reaction is a fundamentally important method for constructing C–C bonds in organic synthesis. The Grignard reagents are usually prepared through the metalation of organohalides. However, organohalides are mostly synthesized via corrosive halogenation reagents, which raises significant environmental concerns and increases the overall cost for the waste disposal. Consequently, it is essential to investigate alternative non-organohalide functionalities to access the Grignard-type reactivity. In this mini-review, we have summarized recent approaches to generating carbanions (or the equivalents) from carboxylic acids, ketones, aldehydes, olefins, and amines.

In this work, a Leslie-Gower model with a weak Allee effect on the prey and a fear effect on the predator is proposed. By using qualitative analyses, the local stability of the coexisting equilibrium and the existence of Turing instable are discussed. By analyzing the distribution of eigenvalues, the existence of a Hopf bifurcation is studied by using the gestation time delay as a bifurcation parameter. By utilizing the normal form method and the center manifold theorem, we calculate the direction of the Hopf bifurcation and the stability of bifurcating periodic solutions. We indicate that both the weak Allee effect on the prey and fear effect on the predator have an important impact on the dynamical behaviour of the new Leslie-Gower model. We also verify the obtained results by some numerical examples.

Low-energy cosmic rays (LECRs) play a crucial role in the formation of planetary systems, and detecting and reconstructing the properties of early LECRs is essential for understanding the mechanisms of planetary system formation. Given that LECRs interact with the surrounding medium to produce nuclear de-excitation line emissions, which are gamma-ray emissions with energy mainly within 0.1–10 MeV and are unaffected by stellar wind modulation, these emissions can accurately reflect the properties of LECRs. This study introduces an innovative method for using gamma-ray emissions to infer LECR properties. We employed the Parker transport equation to simulate the propagation and spectral evolution of LECRs in a protoplanetary disk and calculated the characteristic gamma-ray emissions resulting from interactions between LECRs and disk material. These gamma-ray emissions encapsulate the spectral information of LECRs, providing a powerful tool to reconstruct the cosmic ray environment at that time. This method, supported by further theoretical developments and observations, will fundamentally enhance our understanding of the impact of CRs on the origin and evolution of planetary systems and address significant scientific questions regarding the cosmic ray environment at the origin of life.

Pulsar timing arrays (PTAs) can detect disturbances in the fabric of spacetime on a galactic scale by monitoring the arrival time of pulses from millisecond pulsars (MSPs). Recent advancements have enabled the use of γ -ray radiation emitted by MSPs, in addition to radio waves, for PTA experiments. Wave dark matter (DM), a prominent class of DM candidates, can be detected with PTAs due to its periodic perturbations of the spacetime metric. In response to this development, we perform in this Letter a first analysis of applying the γ -ray PTA to detect the ultralight axion-like wave DM, with the data of Fermi Large Area Telescope (Fermi-LAT). Despite its much smaller collecting area, the Fermi-LAT γ -ray PTA demonstrates a promising sensitivity potential. We show that the upper limits not far from those of the dedicated radio-PTA projects can be achieved. Moreover, we initiate a cross-correlation analysis using the data of two Fermi-LAT pulsars. The cross-correlation of phases, while carrying key information on the source of the spacetime perturbations, has been ignored in the existing data analyses for the wave DM detection with PTAs. Our analysis indicates that taking this information into account can improve the sensitivity to wave DM by ≳50% at masses below 10 ^−23 eV.

Local sheep in the northeastern Tarim Basin can adapt to dry and low-rainfall regional environments. In this study, three local sheep breeds in the northeastern Tarim Basin, LOP (LOP) sheep, Bayinbuluke (BYK) sheep, and Kunlun (KUN, also known as the Qiemo sheep) sheep, and three introduced sheep breeds, Suffolk (SUF) sheep, Dorset (APD) sheep, and Texel (TEX) sheep, were analyzed for genetic diversity, population structure, and selective signature using the Illumina OvineSNP50K BeadChip. We found that LOP, BYK, and KUN had lower observed heterozygosity and expected heterozygosity than TEX, SUF, and ADP, which were differentiated based on geographic distribution. We performed fixation index (FST) analysis on three local sheep breeds in the northeastern Tarim Basin (LOP, BYK, and KUN) and introduced sheep breeds (TEX, SUF, and ADP) to measure genetic differentiation. Nucleotide diversity (PI) analysis was performed on single-nucleotide polymorphism (SNP) data of LOP, BYK, and KUN. A total of 493 candidate genes were obtained by taking the intersection at a threshold of 5%. Among them, SMAD2, ESR2, and HAS2 were related to reproductive traits. PCDH15, TLE4, and TFAP2B were related to growth traits. SOD1, TSHR, and DNAJB5 were related to desert environmental adaptation. Analyzing the genetic patterns of local sheep in the northeastern Tarim Basin can protect the germplasm resources of local sheep and promote the development and utilization of sheep genetic resources.

In order to delay the browning and prolong the shelf life of fresh-cut eggplant during storage, the optimal concentrations of furfuryl thioacetate (FT) on overall sensory quality, browning degree, the activities of enzymes related to browning, contents of total phenol and quinone, and total antioxidant capacity of fresh-cut eggplant during storage at 4 ℃ were investigated. The results showed that 0.64 mmol/L FT treatment significantly inhibited the browning, maintained its overall sensory quality, and prolonged the shelf life of fresh-cut eggplant during storage at 4 ℃ up to day 5. Further studies indicated that 0.64 mmol/L FT treatment suppressed the activities of polyphenol oxidase (PPO) and peroxidase (POD), increased phenylalanine ammonialyase (PAL) activity and DPPH free radical scavenging rate compared with control. In addition, 0.64 mmol/L FT treatment also decreased the contents of total phenol and quinone. Therefore, FT, as a novel anti-browning inhibitor, can delay the browning of fresh-cut eggplant and prolong its shelf life.

In this paper, a delayed diffusive predator-prey model with the Allee effect and nonlocal competition in prey and hunting cooperation in predators is proposed. The local stability of coexisting equilibrium and the existence of Hopf bifurcation are studied by analyzing the eigenvalue spectrum. The property of Hopf bifurcation is also studied by the center manifold theorem and normal form method. Through numerical simulation, the analysis results are verified, and the influence of these parameters on the model is also obtained. Firstly, increasing the Allee effect parameter $ \beta $ and hunting cooperation parameter $ \alpha $ is not conducive to the stability of the coexistence equilibrium point under some parameters. Secondly, the time delay can also affect the stability of coexisting equilibrium and induce periodic solutions. Thirdly, the nonlocal competition in prey can affect the dynamic properties of the predator-prey model and induce new dynamic phenomena (stably spatially inhomogeneous bifurcating periodic solutions).

Since the distribution of plankton is always uneven, the nonlocal phytoplankton competition term indicates the spatial weighted mean of phytoplankton density, which is introduced into the plankton model with toxic substances effect to study the corresponding dynamic behavior. The stability of the positive equilibrium point and the existence of Hopf bifurcations are discussed by analysing the distribution of eigenvalues. The direction and stability of bifurcation periodic solution are researched based on an extended central manifold method and normal theory. Finally, spatially inhomogeneous oscillations are observed in the vicinity of the Hopf bifurcations. Through numerical simulation, we can observe that the system without nonlocal competition term only generates homogeneous periodic solution, and inhomogeneous periodic solution will produce only when both diffusion and nonlocal competition exist simultaneously. We can also see that when the toxin-producing rate of each phytoplankton is in an appropriate range, the system with nonlocal competition generates a stability switch with inhomogeneous periodic solution, when the value of time delay is in a certain interval, then Hopf bifurcations will appear, and with the increase of time delay, the quantity of plankton will eventually become stable.

IntroductionA warming global climate is expected to perturb the hydrological cycle, resulting in deviations in both frequency and duration of drought and thus being hypothesized to lead to interannual variation in evapotranspiration (ET). Interannual variation in ET in urban forest ecosystems in response to drought remains poorly understood.MethodsHere, ET in an urban forest reserve in the megalopolis of Beijing was investigated using eddy-covariance measurements collected over six consecutive years (2012–2017).ResultsThe mean annual cumulative ET was 462 ± 83mm (±first standard deviation), with a coefficient of variation of 18%. Interannual variation in both annual and monthly ET was shown to be largely controlled by canopy conductance (gs), affected by environmental factors. The main factors affecting interannual variation in monthly ET varied seasonally, namely, soil volumetric water content (VWC) and normalized difference vegetation index (NDVI) in spring, precipitation and soil temperature in summer, and VWC and net radiation (Rn) in autumn. Interannual variation in annual ET was driven largely by spring and mid-summer droughts induced by insufficient precipitation during the non-growing and mid-growing seasons, respectively. Spring drought reduced annual ET by restricting leafing out, shortening growing season length (GSL), and reducing the normalized difference vegetation index (NDVI). The summer drought reduced annual ET by reducing stomatal conductance.Discussion and conclusionResults from this study point to the importance of precipitation timing and volume and the soil moisture carry-over effect in controlling interannual variation in ecosystem ET. Irrigation during the early spring and mid-summer is viewed as a practical management measure for sustaining growth and better ecosystem services in urban forests in Northern China.

Abstract The nonlocal competition in prey and schooling behavior among predators are incorporated in a delayed diffusive predator–prey model. Our main interest is to study the dynamic properties of the model generated by nonlocal competition and delay. We mainly concentrate on the stability and Hopf bifurcation at the coexisting equilibrium. Compared with the model without nonlocal competition, our results suggest that nonlocal competition can affect the stability of the coexisting equilibrium, and induce the stably spatial bifurcating periodic solutions.

We consider a delayed diffusive predator-prey system with nonlocal competition in prey and schooling behavior in predator. We mainly study the local stability and Hopf bifurcation at the positive equilibrium by using time delay as the parameter. We also analyze the property of Hopf bifurcation by center manifold theorem and normal form method. Through the numerical simulation, we obtain that time delay can affect the stability of the positive equilibrium and induce spatial inhomogeneous periodic oscillations of prey and predator's population densities. In addition, we observe that the increase of space area will not be conducive to the stability of the positive equilibrium (u∗,v∗,), and may induce the inhomogeneous periodic oscillations of prey and predator's population densities under some values of the parameters.

A delayed diffusive predator-prey system with nonlocal competition and generalist predators is considered. The local stability of the positive equilibrium and Hopf bifurcation at positive equilibrium is studied by using time delay as a parameter. In addition, the property of Hopf bifurcation is analyzed using the center manifold theorem and normal form method. It is determined that time delays can affect the stability of the positive equilibrium and induce spatial inhomogeneous periodic oscillation of prey and predator population densities.

The spatial memory effect in predator and fear effect in prey are incorporated in a diffusive predator-prey model. We are interested in studying the dynamics generated by the memory effect and fear effect, and mainly study the local stability of coexisting equilibrium, the existence of Hopf bifurcation and the property of Hopf bifurcation. Through the numerical simulations, we show that increasing memory-based diffusion coefficient is not conducive to the stability of the coexisting equilibrium, and the fear effect has both stabilizing and destabilizing effect on the coexisting equilibrium under different parameters.

Time delay in the resource limitation of the prey is incorporated into a diffusive predator-prey model with generalist predator. By analyzing the eigenvalue spectrum, time delay inducing instability and Hopf bifurcation are investigated. Some conditions for determining the bifurcation direction and the stability of the bifurcating periodic solution are obtained by utilizing the normal form method and center manifold reduction for partial functional differential equation. The results suggest that time delay can destabilize the stability of coexisting equilibrium and induce bifurcating periodic solution when it increases through a certain threshold.

Hepatic steatosis is a highly prevalent liver disease, yet research on it is hampered by the lack of tractable cellular models in poultry. To examine the possibility of using organoids to model steatosis and detect it efficiently in leghorn male hepatocellular (LMH) cells, we first established steatosis using different concentrations of oleic acid (OA) (0.05–0.75 mmol/L) for 12 or 24 h. The subsequent detections found that the treatment of LMH cells with OA resulted in a dramatic increase in intracellular triglyceride (TG) concentrations, which was positively associated with the concentration of the inducing OA (R2 > 0.9). Then, the modeled steatosis was detected by flow cytometry after NileRed staining and it was found that the intensity of NileRed-A was positively correlated with the TG concentration (R2 > 0.93), which demonstrates that the flow cytometry is suitable for the detection of steatosis in LMH cells. According to the detection results of the different steatosis models, we confirmed that the optimal induction condition for the establishment of the steatosis model in LMH cells is OA (0.375 mmol/L) incubation for 12 h. Finally, the transcription and protein content of fat metabolism-related genes in steatosis model cells were detected. It was found that OA-induced steatosis could significantly decrease the expression of nuclear receptor PPAR-γ and the synthesis of fatty acids (SREBP-1C, ACC1, FASN), increasing the oxidative decomposition of triglycerides (CPT1A) and the assembly of low-density lipoproteins (MTTP, ApoB). Sterol metabolism in model cells was also significantly enhanced (HMGR, ABCA1, L-BABP). This study established, detected, and analyzed an OA-induced steatosis model in LMH cells, which provides a stable model and detection method for the study of poultry steatosis-related diseases.

Peony seeds, an important oil resource, have been attracting much attention because of α-linolenic acid. Oil bodies (OBs), naturally pre-emulsified oils, have great potential applications in the food industry. This study investigated the effects of extraction pH and Quillaja saponin (QS) on the physicochemical properties of peony oil body (POB) emulsions. POBs were extracted from raw peony milk at pH 4.0, 5.0, 6.0, and 7.0 (named pH 4.0-, 5.0-, 6.0-, and 7.0-POBs). All POBs contained extrinsic proteins and oleosins. The extrinsic proteins of pH 4.0- and pH 5.0-POB were 23 kDa and 38 kDa glycoproteins, the unknown proteins were 48 kDa and 60 kDa, while the 48 kDa and 38 kDa proteins were completely removed under the extraction condition of pH 6.0 and 7.0. The percentage of extrinsic proteins gradually decreased from 78.4% at pH 4.0-POB to 33.88% at pH 7.0-POB, while oleosin contents increased. The particle size and zeta potential of the POB emulsions decreased, whereas the oxidative stability, storage stability, and pI increased with the increasing extraction pH. QS (0.05~0.3%) increased the negative charges of all the POB emulsions, and 0.1% QS significantly improved the dispersion, storage, and the oxidative stability of the POB emulsions. This study provides guidance for selecting the proper conditions for the aqueous extraction of POBs and improving the stability of OB emulsions.

Abstract Based on the predator–prey system with a Holling type functional response function, a diffusive predator–prey system with digest delay and habitat complexity is proposed. Firstly, the stability of the equilibrium of diffusion system without delay is studied. Secondly, under the Neumann boundary conditions, taking time delay as the bifurcation parameter, by analyzing the eigenvalues of linearized operator of the system and using the normal form theory and center manifold method of partial functional differential equations, the effect of time delay on the stability of the system is studied and the conditions under which Hopf bifurcation occurs are given. In addition, the calculation formulas of the bifurcation direction and the stability of bifurcating periodic solutions are derived. Finally, the accuracy of theoretical analysis results is verified by numerical simulations and the biological explanation is given for the analysis results.

Abstract In this paper, we consider a diffusive predator–prey model with a time delay and prey toxicity. The effect of time delay on the stability of the positive equilibrium is studied by analyzing the eigenvalue spectrum. Delay-induced Hopf bifurcation is also investigated. By utilizing the normal form method and center manifold reduction for partial functional differential equations, the formulas for determining the property of Hopf bifurcation are given.

Abstract Background It is well known that the biomechanical properties change after LASIK refractive surgery. One reason is the impact of flap creation on the residual stroma. The results have revealed that the change is closely related with the flap thickness in several studies. However, the quantitative relationships between the distributions of displacement and stress on the corneal surface and flap thickness have not been studied. The aim of the study was to quantify evaluate the biomechanical change caused by the LASIK flap. Methods By building a finite element model of the cornea, the displacement, the stress and the strain on the corneal surface were analyzed. Results The results showed that the corneal flap could obviously cause the deformation of the anterior corneal surface. For example, the displacement of the corneal vertex achieved 15 μm more than that without corneal flap, when the thickness of corneal flap was 120 μm thick. This displacement was enough to cause the change of aberrations in the human eyes. In the central part of the cornea, the stress on the anterior corneal surface increased with flap thickness. But the change in the stress on the posterior corneal surface was significantly less than that on the anterior surface. In addition, the stress in the central part of the anterior corneal surface increased significantly as the intra-ocular pressure (IOP) increase. Furthermore the increase of IOP had a clearly less effect on stress distribution at the edge of the cornea. Distributions of strain on the corneal surface were similar to those of stress. Conclusions The changes in the biomechanical properties of cornea after refractive surgery should not be ignored.

In this paper, we propose a diffusive predator–prey model with a strong Allee effect and nonlocal competition in the prey and a fear effect and gestation delay in the predator. We mainly study the local stability of the coexisting equilibrium and the existence and properties of Hopf bifurcation. We provide bifurcation diagrams with the fear effect parameter (s) and the Allee effect parameter (a), showing that the stable region of the coexisting equilibrium increases (or decreases) with an increase in the fear effect parameter (s) (or the Allee effect parameter (a)). We also show that gestation delay (τ) can affect the local stability of the coexisting equilibrium. When the delay (τ) is greater than the critical value, the coexistence equilibrium loses its stability, and bifurcating periodic solutions appear. Whether the bifurcated periodic solution is spatially homogeneous or inhomogeneous depends on the fear effect parameter (s) and the Allee effect parameter (a). These results show that the fear effect parameter (s), the Allee effect parameter (a), and gestation delay (τ) can be used to control the growth of prey and predator populations.

Although lithium (Li) metal anode/lithium–manganese‐rich (LMR) cathode batteries have an ultrahigh energy density, the highly active Li metal and structural deterioration of LMR can make the usage of these batteries difficult. Herein, a multifunctional electrolyte containing LiBF4 and LiFSI dual‐salt additives is designed, which enables the superior cyclability of Li/LMR cells with capacity retentions of ≈83.4%, 80.4%, and 76.6% after 400 cycles at 0.5, 1, and 2 C, respectively. The dual‐salt electrolyte can form a thin, uniform, and inorganic species‐rich solid electrolyte interphase (SEI) and cathode electrolyte interphase (CEI). In addition, it alleviates the bulk Li corrosion and enhances the structural sustainability of LMR cathode. Moreover, the electrolyte design strategy provides insights to develop other high‐voltage lithium metal batteries (HVLMBs) to enhance the cycle stability.

A delayed diffusive predator-prey model with predator interference or foraging facilitation is studied. We are interested in the existence of Turing instability, local stability, and Hopf bifurcation. We analyze the direction and stability of bifurcating periodic solutions by the normal form method. Our results suggest that diffusion can induce Turing instability and time delay can induce oscillation of prey and predator’s densities. In addition, the interference parameter λ0 has stabilizing and destabilizing effect on the positive equilibrium.

In this paper, a diffusive predator–prey model with a memory effect in predator and anti-predator behaviour in prey is studied. The stability of the coexisting equilibrium and the existence of Hopf bifurcation are analysed by analysing the distribution of characteristic roots. The property of Hopf bifurcation is investigated by the theory of the centre manifold and normal form method. Through the numerical simulations, it is observed that the anti-predator behaviour parameter η, the memory-based diffusion coefficient parameter d, and memory delay τ can affect the stability of the coexisting equilibrium under some parameters and cause the spatially inhomogeneous oscillation of prey and predator’s densities.

Rothia nasimurium is a facultative anaerobic Gram-positive coccus belonging to the Rothia genus of the Micrococcaceae family. While Rothia nasimurium is considered an opportunistic pathogen, to date few studies have investigated its pathogenicity and drug resistance. In January 2022, chickens at a poultry farm in China’s Xinjiang Uygur Autonomous Region became ill and died. Treatment with commonly used Chinese medicines and antibiotics was ineffective, causing economic losses to the poultry farm. In order to determine the cause of the disease in these poultry farm chickens, the isolation and identification of the pathogens in the livers and other internal organs of the sick and dead chickens were performed. Further, animal pathogenicity tests, antibiotic susceptibility tests, and the detection of antibiotic resistance genes were carried out to analyze the pathogenicity and drug resistance of the identified pathogens. A Gram-positive coccus was isolated from the livers of the diseased chickens. The isolate was resistant to 17 antibiotics, including ciprofloxacin, chloramphenicol, and florfenicol, and was only sensitive to penicillin, amikacin, and tigecycline, to varying degrees. The results of the drug resistance gene testing indicated that the isolated bacterium carried 13 kinds of resistance genes. Matrix-assisted laser desorption/ionization time-of-flight mass spectrometry, morphological observations, biochemical tests, and 16S rRNA gene sequence analysis were performed on the isolated bacterium, and it was determined that the isolated bacterial strain was Rothia nasimurium. The animal pathogenicity tests showed that the isolate caused feather loss and death in chicks; the clinical symptoms and necropsy lesions of the test chicks were consistent with those observed in the farmed chickens. A review of the literature revealed that, to date, there are no reports of infection with Rothia nasimurium in chickens. Thus, in this study, Rothia nasimurium was isolated from chickens for the first time and an investigation of the biological characteristics of the bacterium was carried out in order to provide a reference for the clinical treatment, prevention, and control of Rothia nasimurium infection.

Abstract In this paper, we study a predator–prey model with delay and harvesting on predator. We give the conditions for stability and Turing instability of coexisting equilibrium by analyzing the eigenvalue spectrum. By using delay as a bifurcation parameter we give conditions for occurrence of Hopf bifurcation. We investigate the property of bifurcating period solutions by calculating the normal form. We perform some numerical simulations to support our theoretical result. Our results show that diffusion and delay are two factors that should be considered in establishing the predator–prey model, since they can induced the Turing instability and spatially bifurcating period solutions.

Boron (B) and phosphorus (P) dual-doped carbon microspheres (BPC) were successfully synthesized from onium salts by a facile one-step pyrolysis method. When employed as the anode material for sodium (Na)-ion batteries (NIBs), the resulting BPC delivers a reversible capacity of 221.9 mAh g−1 at 50 mA g−1. Impressively, the BPC can still deliver a capacity of 102 mAh g−1 after 1500 cycles at 1 A g−1 with the capacity retention up to 78%. The high performance of the BPC can be attributed to the significantly increased defects and dilated interlayer distance induced by synergistically B and P co-doping. Keywords: Sodium-ion batteries, Anode, Carbon, Doping, Heteroatom

Abstract The phytoplankton–zooplankton is fundamentally important to study plankton and protect marine environment. In this paper, we propose a diffusive phytoplankton–zooplankton model, in which we also consider time delay in zooplankton predation and harvesting in zooplankton. By analyzing the distribution of eigenvalues, we investigate the stability of the positive equilibrium and the existence of Hopf bifurcation using time delay as a bifurcation parameter. We analyze the property of Hopf bifurcation and give an explicit formula for determining the direction and the stability of Hopf bifurcation. Finally, by numerical simulation, we analyze the effect of harvesting, conversion rate, half-saturation, and time delay. We conclude that harvesting parameter, conversion rate, and half-saturation constant all can be used in controlling the bloom of plankton population.

For an array of applications of the high voltage pulse discharge technology in reservoir stimulations and to gain a deeper understanding of the fractures mechanism of deep well rock under cyclic electrohydraulic shock waves (EHSWs), the effect of confining pressure and hydrostatic pressure on the fracturing of rock under EHSWs are investigated in this paper. Firstly, a two-dimensional (2D) water-explosive numerical model is built to match the computed peak pressure of the EHSW with that obtained by the empirical formula by tuning the relevant parameters, based on the equivalent method of EHSWs. Then, a rock model is established to obtain the stress distribution under static loads. Subsequently, the water-explosive model is coupled with the rock model to obtain the stress distribution under static and dynamic loads. In addition, based on this coupling model, the influences of confining pressure and hydrostatic pressure on circumferential stress, radial stress in the rock and the fracturing of rock around the wellbore are discussed. Finally, two improvement measures (increasing discharge energy and changing loading mode) are proposed to acquire greater fracture density based on intensive numerical simulations. The results show that the increase in hydrostatic pressure is beneficial to the crack formation and development, whereas confining pressure is harmful. Moreover, the inhibitory effect of confining pressure on crack formation is greater than the promotion effect of hydrostatic pressure on crack formation. Increasing the discharge energy can effectively promote the development of the number and length of main cracks. Under four repetitive loading modes with the same total discharge energy (1.36 × 15 kJ), the greatest fracture density can be obtained by using repetitive loading mode with a gradually decreasing mode of discharge energy (first level: 2 times (1.36 × 5 kJ); second level: 5 times (1.36 × 1 kJ)).

Radiation components have distinct effects on photosynthesis. In the desert steppe ecosystem, the influence of diffuse radiation on carbon fixation has not been thoroughly explored. We examined this diffusion and its effect on ecosystem productivity was examined during the growing season from 2014 to 2015 on the basis of eddy covariance measurements of CO2 exchange in a desert steppe ecosystem in northwest China. Our results indicated that the gross ecosystem production (GEP) and diffuse photosynthetically active radiation (PARdif) peaked when the clearness index (CI) was around 0.5. The maximum canopy photosynthesis (Pmax) under cloudy skies (CI < 0.7) was 23.7% greater than under clear skies (CI ≥ 0.7). When the skies became cloudy in the desert steppe ecosystem, PARdif had a greater effect on GEP. Additionally, lower vapor pressure deficits (VPD ≤ 1 kPa), lower air temperatures (Ta ≤ 20 °C), and non-stressed water conditions (REW ≥ 0.4) were more conducive for enhanced ecosystem photosynthesis under cloudy skies than under clear skies. This may be due to the comprehensive effects of VPD and Ta on stomatal conductance. We concluded that cloudiness can influence diffuse radiation components and that diffuse radiation can increase the ecosystem production of desert steppe ecosystems in northwest China.

Vaporization of water during both gas reservoir development and CO2 geological sequestration in saline formations can cause salt precipitation with rapid loss of formation porosity and permeability. Water vaporization and precipitation of halite around a single well from stage production to CO2 injection are studied to investigate the effect on reservoir properties in a gas reservoir. This paper identifies and quantifies post-flood dry zones and permeability changes in depleted gas reservoir after CO2 exposure with the comparison in gas production period by performing the numerical simulation with the compositional simulator. Simulation results indicate that water vaporization and salt precipitation occur during gas production, and can be intensified by CO2 injection. Dry supercritical CO2 injection vaporizes the brine promoting brine concentration and halite precipitation. The simulation indicates a drying area with a radius of 78 m around wellbore after CO2 injection. Porosity reduces with the most scope of 58%, and permeability can be decreased by up to 93.9% due to salt precipitation. And the injectivity is damaged by 99.77% at the end of injection period based on maximum permeability reduction. Moreover, six factors are investigated to conduct the influence analysis, showing that higher salinity brine, higher injection rate, higher irreducible water saturation, lower initial permeability, higher temperature and with capillary flow are conditions enhancing the salt precipitation due to dry CO2 injection.

Abstract In this paper, we consider a modified predator–prey model with Michaelis–Menten-type predator harvesting and diffusion term. We give sufficient conditions to ensure that the coexisting equilibrium is asymptotically stable by analyzing the distribution of characteristic roots. We also study the Turing instability of the coexisting equilibrium. In addition, we use the natural growth rate r1 $r_{1}$ of the prey as a parameter and carry on Hopf bifurcation analysis including the existence of Hopf bifurcation, bifurcation direction, and the stability of the bifurcating periodic solution by the theory of normal form and center manifold method. Our results suggest that the diffusion term is important for the study of the predator–prey model, since it can induce Turing instability and spatially inhomogeneous periodic solutions. The natural growth rate r1 $r_{1}$ of the prey can also affect the stability of positive equilibrium and induce Hopf bifurcation.

We studied a delayed predator–prey model with diffusion and anti-predator behavior. Assume that additional food is provided for predator population. Then the stability of the positive equilibrium is considered. The existence of Hopf bifurcation is also discussed based on the Hopf bifurcation theory. The property of Hopf bifurcation is derived through the theory of center manifold and normal form method. Finally, we analyze the effect of time delay on the model through numerical simulations.

In this paper, we studied a nutrient–phytoplankton model with time delay and diffusion term. We studied the Turing instability, local stability, and the existence of Hopf bifurcation. Some formulas are obtained to determine the direction of the bifurcation and the stability of periodic solutions by the central manifold theory and normal form method. Finally, we verify the above conclusion through numerical simulation.

In this paper, a diffusive predator–prey system with a functional response that increases in both predator and prey densities is considered. By analyzing the characteristic roots of the partial differential equation system, the Turing instability and Hopf bifurcation are studied. In order to consider the dynamics of the model where the Turing bifurcation curve and the Hopf bifurcation curve intersect, we chose the diffusion coefficients d1 and β as bifurcating parameters. In particular, the normal form of Turing–Hopf bifurcation was calculated so that we could obtain the phase diagram. For parameters in each region of the phase diagram, there are different types of solutions, and their dynamic properties are extremely rich. In this study, we have used some numerical simulations in order to confirm these ideas.

Abstract The dynamics of a diffusive predator-prey system with prey refuge and gestation delay is investigated in this paper. For a non-delay system, global stability, Turing instability and Hopf bifurcation are studied. For a delay system, time delay induced instability and Hopf bifurcation are discussed. By the theory of normal form and the center manifold method, the direction and stability of the bifurcating periodic solution are discussed.

This paper proposed and evaluated a programmable ROADM system for MCF-based SDM/WDM networks. The proposed ROADM system employing both bypass connection and Route-and-Select wavelength switching enables adaptable virtual topology in optical networks by dynamically configuring bypass connection cores. The simulation results confirmed this ROADM system could provide acceptable performance with an around 10–20% reduction in the total cost including the number of ports and WSSs by comparing with a fully flexible SDM/WDM ROADM system, which cannot be implemented due to the required extremely high-port-count WSSs.

As a laboratory-on-a-chip application tool, digital microfluidics (DMF) technology is widely used in DNA-based applications, clinical diagnosis, chemical synthesis, and other fields. Additional components (such as heaters, centrifuges, mixers, etc.) are required in practical applications on DMF devices. In this paper, a DMF chip interconnection method based on electrowetting-on-dielectric (EWOD) was proposed. An open modified slippery liquid-infused porous surface (SLIPS) membrane was used as the dielectric-hydrophobic layer material, which consisted of polytetrafluoroethylene (PTFE) membrane and silicone oil. Indium tin oxide (ITO) glass was used to manufacture the DMF chip. In order to test the relationship between the splicing gap and droplet moving, the effect of the different electrodes on/off time on the minimum driving voltage when the droplet crossed a splicing gap was investigated. Then, the effects of splicing gaps of different widths, splicing heights, and electrode misalignments were investigated, respectively. The experimental results showed that a driving voltage of 119 V was required for a droplet to cross a splicing gap width of 300 μm when the droplet volume was 10 μL and the electrode on/off time was 600 ms. At the same time, the droplet could climb a height difference of 150 μm with 145 V, and 141 V was required when the electrode misalignment was 1000 μm. Finally, the minimum voltage was not obviously changed, when the same volume droplet with different aqueous solutions crossed the splicing gap, and the droplet could cross different chip types. These splicing solutions show high potential for simultaneous detection of multiple components in human body fluids.

In 2008, the top CO2 emitters were China, United States, and European Union. The rapid growing economy and the heavy reliance on coal in China give rise to the continued growth of CO2 emission, deterioration of anthropogenic climate change, and urgent need of new technologies. Carbon Capture and sequestration is one of the effective ways to provide reduction of CO2 emission and mitigation of pollution. Coal-fired power plants are the focus of CO2 source supply due to their excessive emission and the energy structure in China. And over 80% of the large CO2 sources are located nearby storage reservoirs. In China, the CO2 storage potential capacity is of about 3.6 × 109 t for all onshore oilfields; 30.483 × 109 t for major gas fields between 900 m and 3500 m of depth; 143.505 × 109 t for saline aquifers; and 142.67 × 109 t for coal beds. On the other hand, planation, soil carbon sequestration, and CH4–CO2 reforming also contribute a lot to carbon sequestration. This paper illustrates some main situations about CO2 sequestration applications in China with the demonstration of several projects regarding different ways of storage. It is concluded that China possesses immense potential and promising future of CO2 sequestration.