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The traditional standard wet sieving method uses steel sieves with aperture ≥0.063 mm and can only determine the particle size distribution (PSD) of gravel and sand in general soil. This paper extends the traditional method and presents an extended wet sieving method. The extended method uses both the steel sieves and the nylon filter cloth sieves. The apertures of the cloth sieves are smaller than 0.063 mm and equal 0.048 mm, 0.038 mm, 0.014 mm, 0.012 mm, 0.0063 mm, 0.004 mm, 0.003 mm, 0.002 mm, and 0.001 mm, respectively. The extended method uses five steps to separate the general soil into many material sub-groups of gravel, sand, silt and clay with known particle size ranges. The complete PSD of the general soil is then calculated from the dry masses of the individual material sub-groups. The extended method is demonstrated with a general soil of completely decomposed granite (CDG) in Hong Kong, China. The silt and clay materials with different particle size ranges are further examined, checked and verified using stereomicroscopic observation, physical and chemical property tests. The results further confirm the correctness of the extended wet sieving method.

Abstract Background In China, adolescents account for about a quarter of those treated for mental disorders each year, and adolescent mental health issues have become a social hotspot. Although several epidemiological surveys of mental disorders have been conducted in China, no study has yet focused on the prevalence of mental disorders among adolescents in a certain region of Zhejiang. Methods In the first stage, 8219 middle school students aged 12–18 years in a city of Zhejiang Province (Shaoxing) were screened with the mental health screening checklist. In the second stage, participants who screened positive were tested with the Mini International Neuropsychiatric Interview for Children and Adolescents (MINI-KID) and the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition (DSM-IV). Then, the prevalence of mental disorders were calculated. Results The overall prevalence in this population was 12.4%, with prevalence rates exceeding 20% in both the 17- and 18-year-old age groups. The most common mental disorders were obsessive–compulsive disorder (OCD) (9.1%) and major depressive disorder (MDD) (8.9%). Conclusions Mental disorders are common among middle school students, and girls are at higher risk than boys. As the most prevalent mental disorders, OCD and MDD should receive timely attention, especially for upper grade students.

Transarterial chemoembolization (TACE) is a first-line treatment for intermediate to advanced-stage liver cancer, with drug-eluting microspheres commonly used as embolic agents. However, currently available drug-eluting microspheres suffer from low drug-loading capacity and limited drug options. In this work, we developed polydopamine-modified polyvinyl alcohol dual-drug-loaded microspheres encapsulating celecoxib and cisplatin (referred to as PCDMS). Physicochemical characterization revealed that the surface of the microspheres displayed increased roughness after polydopamine modification, and celecoxib and cisplatin were successfully loaded onto the microsphere surface. In vitro cell experiments demonstrated that the PCDMS significantly inhibited the proliferation and migration of highly metastatic human liver cancer cells (MHCC-97H) and human liver cancer cells (SMMC-7721). Furthermore, the dual-loaded microspheres exhibited remarkable tumor growth inhibition and reshaped the tumor microenvironment in both subcutaneous H22 liver cancer model in Balb/c mice and intrahepatic VX2 tumor model in New Zealand rabbits, demonstrating a synergistic antitumor effect where 1 + 1>2. This work provides a potential therapeutic approach for the treatment of refractory liver cancer and holds significant translational potential.

Symbiosis between soybean and rhizobia contributes to soybean yield and quality. Although secreted rhizobial type III effectors are known to regulate infection and promote nitrogen fixation, much about them remains unknown. Mutation of NopC, a type III effector from Sinorhizobium fredii HH103, reduced nodule numbers and dry weights in 310 soybean accessions, and expression of NopC in soybean hairy roots promoted symbiosis. Based on observed differences in nodule traits between Suinong 14 and Zyd 00,006 inoculated with HH103 and the NopC mutant, 11 QTL associated with rhizobia were identified in chromosome segment substitution lines (CSSLs) derived from Suinong 14 and Zyd 00006. Using chromosome fragment insertion, whole-genome sequencing of Suinong 14 and Zyd 00006, and qRT-PCR, Glyma.19G176300 (GmCRP) was identified as a candidate gene associated with NopC, and GmCRP was found to be induced by NopC to positively regulate nodulation. SNPs located in the regulatory regions of GmCRP influenced its expression response to NopC, with SNPs contributing to nodulation having been selected during domestication. Our findings reveal the function of a soybean gene encoding a rhizobial type III effector that contributes to symbiosis, and will facilitate the practical application of symbiotic nitrogen fixation in molecular breeding.

Residual tumor recurrence after surgical resection of hepatocellular carcinoma (HCC) remains a considerable challenge that imperils the prognosis of patients. Notably, intraoperative bleeding and postoperative infection are potential risk factors for tumor recurrence. However, the biomaterial strategy for the above problems has rarely been reported. Herein, a series of cryogels (coded as SQ-n) based on sodium alginate (SA) and quaternized chitosan (QC) were synthesized and selected for optimal ratios. The in vitro assays showed that SQ-50 possessed superior hemostasis, excellent antibacterial property, and great cytocompatibility. Subsequently, SQAP was constructed by loading black phosphorus nanosheets (BPNSs) and anlotinib hydrochloride (AL3818) based on SQ-50. Physicochemical experiments confirmed that near-infrared (NIR)-assisted SQAP could control the release of AL3818 in photothermal response, significantly inhibiting the proliferation and survival of HUVECs and H22 cells. Furthermore, in vivo studies indicated that the NIR-assisted SQAP prevented local recurrence of ectopic HCC after surgical resection, achieved through the synergistic effect of mPTT and molecular targeted therapy. Thus, the multifunctional SQAP provides a “one-stop” synergistic strategy for HCC postoperative recurrence, showing great potential for clinical application.

Soybean (Glycine max) is a vital food crop, serving as a major source of high-quality protein for human and animal consumption. Stem diameter is one of the primary determinants of the stem lodging resistance of a given plant, but there has been relatively little research to date focused on genes associated with this trait. To address this gap in the literature, 207 chromosome segment substitution lines (CSSLs) were generated in the present study through the crossing and backcrossing of the improved Suinong14 and the wild ZYD00006 soybean varieties. These CSSLs were then used for the mapping of quantitative trait loci (QTLs) associated with stem diameter in two-year field planting materials, leading to the identification of nine QTLs. Whole genome resequencing, RNA-seq, and qPCR were then used to evaluate candidate genes associated with stem diameter within these QTL intervals, ultimately leading to the selection of Glyma.04G004100 as a stem diameter-related gene. Subsequent qPCR analyses revealed that Glyma.04g004100 was upregulated in soybean plants with larger stem diameters, and haplotype analyses yielded results consistent with these stem diameter data in the population used to conduct this study. In summary, a series of QTLs associated with stem diameter were identified in the present study, resulting in the establishment of Glyma.04g004100 as a stem diameter-related gene. Together, these results offer a theoretical foundation for the future molecular-assisted breeding of lodging-resistant soybean varieties, and future functional research focused on Glyma.04g004100 may elucidate the molecular mechanisms and key signaling networks involved in soybean stem development.

Abstract Background This study was to evaluate the efficacy and safety of the implantation of foldable capsular vitreous body (FCVB) in severe retinal detachment eyes. Methods A retrospective study in retinal detachment eyes was performed at Shandong Provincial Hospital Affiliated to Shandong First Medical University. A standard three-port pars plana vitrectomy was performed, and the FCVB was triple folded and implanted into the vitreous cavity. The silicone oil (SO) was then injected into the capsule of the FCVB to support the retina and eye. During the follow-up period, The treated eyes were examined by ophthalmoscopy, fundus photography, and tonometry. B-scan ultrasonography, optical coherence tomography (OCT), and computed tomography (CT), were also performed. Results From May 2020 to November 2021, 31 cases with severe retinal detachment were enrolled in the study. The postoperative follow-up time gradient ranged from 1 to 72 weeks, At various observation time points during the 72 weeks after surgery, The postoperative IOP was maintained at around 10 mmhg at various time points, with a slight decrease compared to the preoperative IOP (14.2 ± 4.6 mmHg n = 18), and was statistically significant. 9 of 31 patients had clear refractive media, both fundus and OCT showed retinal reattachment, OCT showed the 200 μm thick FCVB capsule support retina. The remaining 22 patients with unclear refractive media, B-scan showed arcuate hyperechoes in front of the retina. There was also no significant difference in visual acuity compared to preoperative. The FCVB was well positioned in the vitreous cavity, and no serious complications such as endophthalmitis, glaucoma, silicone oil emulsification, product exposure, or sympathetic uveitis were found. Conclusions FCVB has retinal support with certain ability to maintain IOP and eye morphology and avoid eye removal in patients with severe retinal detachment during the 72-week observation period.

Abstract Soybean is a rich source of protein and oil for humans. It forms a symbiotic association with rhizobia to fix atmospheric nitrogen for its growth and development. Rhizobial type‐III effectors act as important signaling molecules in symbiosis. However, they are poorly studied. In this study, mutation of TtsI in Sinorhizobium fredii HH103 reduced nodule numbers and dry weights in SN14 (cultivated soybean) and ZYD00006 (wild soybean). Moreover, it reduced nitrogenase activity in SN14 but not in ZYD00006. Based on the differences in nitrogenase activity between SN14 and ZYD00006 inoculated with HH103 and the TtsI mutant, two conditional quantitative trait loci associated with nitrogenase activity were identified in chromosome segment substitution lines derived from SN14 and ZYD00006. Using transcriptome analysis, single‐nucleotide polymorphism (SNP) analysis, and qRT‐PCR, Glyma.13G150000 (GmTNRP1) was identified as a candidate gene in soybean that was associated with nitrogenase activity, along with NopT (a type‐III effector). In addition, GmTNRP1 (an LRR‐RK family protein located on the cell membrane) was observed to be induced by NopT to negatively regulate nitrogenase activity. In transgenic hairy roots with GmTNRP1 silencing, no significant difference was observed in terms of nitrogenase activity between nodules inoculated with the NopT mutant and those inoculated with HH103 (wild type). However, the nitrogenase activity in the nodules decreased after overexpression of GmTNRP1. SNP located in the GmTNRP1 promoter affected its expression in response to NopT. Haplotype analysis revealed that SN14 belonged to Hap1 and ZYD00006 belonged to Hap2, which explained the different results in the two varieties. To the best of our knowledge, this is the first study to identify a soybean gene associated with a rhizobial type‐III effector in the nodules. GmTNRP1 can negatively regulate nitrogenase activity in the nodules. This study enhanced the understanding of the mechanism underlying symbiotic association between soybean and rhizobia.

Soybean (Glycine max) is an economically important cash crop and food source that serves as a key source of high-quality plant-derived protein and oil. Seed vigor is an important trait that influences the growth and development of soybean plants in an agricultural setting, underscoring a need for research focused on identifying seed vigor-related genetic loci and candidate genes. In this study, a population consisting of 207 chromosome segment substitution lines (CSSLs) derived from the crossing and continuous backcrossing of the Suinong14 (improved cultivar, recurrent parent) and ZYD00006 (wild soybean, donor parent) soybean varieties was leveraged to identify quantitative trait loci (QTLs) related to seed vigor. The candidate genes detected using this approach were then validated through RNA-seq, whole-genome resequencing, and qPCR approaches, while the relationship between specific haplotypes and seed vigor was evaluated through haplotype analyses of candidate genes. Phenotypic characterization revealed that the seed vigor of Suinong14 was superior to that of ZYD00006, and 20 total QTLs were identified using the selected CSSLs. Glyma.03G256700 was also established as a seed vigor-related gene that was upregulated in high-vigor seeds during germination, with haplotypes for this candidate gene also remaining consistent with observed soybean seed vigor. The QTLs identified herein can serve as a foundation for future marker-assisted and convergent breeding efforts aimed at improving seed vigor. In addition, future molecular and functional research focused on Glyma.03G256700 has the potential to elucidate the signaling network and key regulatory mechanisms that govern seed germination in soybean plants.

ABSTRACT: This study was designed to depict prevalence and antimicrobial resistance characteristics of Proteus mirabilis (P. mirabilis) strains in 4 chicken farms and to probe the transfer mechanism of resistance genes. A total of 187 P. mirabilis isolates were isolated from 4 chicken farms. The susceptibility testing of these isolates to 14 antimicrobials showed that the multidrug resistance (MDR) rate was as high as 100%. The β-lactamase resistance genes blaOXA-1, blaCTX-M-1G, blaCTX-M-9G and colistin resistance gene mcr-1 were highly carried in the P. mirabilis isolates. An MDR strain W47 was selected for whole genome sequencing (WGS) and conjugation experiment. The results showed that W47 carried 23 resistance genes and 64 virulence genes, and an SXT/R391 integrated conjugative elements (ICEs) named ICEPmiChn5 carrying 17 genes was identified in chromosome. ICEPmiChn5 was able to be excised from the chromosome of W47 forming a circular intermediate, but repeated conjugation experiments were unsuccessful. Among 187 P. mirabilis isolates, 144 (77.01%, 144/187) isolates carried ICEPmiChn5-like ICEs, suggesting that ICEs may be the major vector for the transmission of resistance genes among MDR chicken P. mirabilis strains in this study. The findings were conducive to insight into the resistance mechanism of chicken P. mirabilis strains and provide a theoretical basis for the use of antibiotics for the treatment of MDR P. mirabilis infections in veterinary clinic.

ABSTRACT: This study aimed to evaluate the effect of isoleucine (Ile) on growth performance, meat quality and lipid metabolism of broilers fed a low-protein diet (LPD). The 396 one-day-old male Cobb broilers were allocated to 4 treatment groups as follows: control diet (CON), LPD, LPD + 0.13% Ile (LPD-LI) and LPD + 0.26% Ile (LPD-HI), with nine replicates of 11 broilers each for 42 d. The Ile increased average daily gain, average daily feed intake, fiber density and the mRNA level of myosin heavy chain (MyHC)-I in breast muscle, and decreased feed to gain ratio, shear force, fiber diameter and the mRNA level of MyHC-IIb in breast muscle, which were impaired by the LPD. Compared to the LPD group, broilers in LPD-LI and LPD-HI groups had lower serum lipid levels, liver fat content, abdominal adipose percentage and mRNA levels of peroxisome proliferator-activated receptor-γ, CCAAT/enhancer binding protein-α, ki-67, topoisomerase II alpha (TOP2A) and thioredoxin-dependent peroxidase 2 in abdominal adipose and liver X receptors-α, sterol regulatory element binding protein 1 (SREBP1), acetyl-CoA carboxylase (ACC) and fatty acid synthase (FAS) in liver, and higher mRNA levels of peroxisome proliferator activated receptor-α, carnitine palmitoyl-transferase 1 (CPT-1), and acyl-CoA oxidase 1 (ACOX1) in liver, which were equal to the CON levels. A LPD supplemented with Ile decreased enzyme activities of ACC and FAS in liver and glycerol-3-phosphate dehydrogenase and TOP2A in abdominal adipose, and increased enzyme activities of CPT-1 and ACOX1 in liver. Furthermore, Ile supplementation enhanced the mRNA level of leptin receptor and protein levels of phospho-5′ adenosine monophosphate-activated protein kinase (AMPK), mechanistic target of rapamycin, ribosomal protein 70 S6 kinase, janus kinase 2 (JAK2), and signal transducer and activator of transcription 3 (STAT3), and decreased the protein level of SREBP1 in the liver of broilers in LPD group. In conclusion, dietary supplementation with Ile to 0.83% could improve growth performance and meat quality and alleviate lipid deposition of broilers fed a LPD through activating AMPK and JAK2/STAT3 signaling pathways.

The appropriate vascularization and anti-inflammatory play an important role in wound healing. Currently, the balance of anti-inflammatory and promoting suitable vascularization for accurate wound healing is still a key issue in this field. The positive factors of controlled release, suitable thermal environment, desired structure, and composition can provide an ideal comprehensive strategy for this problem. Herein, we prepared near-infrared (NIR)-responsive MXene nanofibers and hydrogel double structure system (MNFs@DFOM-H@AC) with two types of positive factors loading, deferoxamine mesylate (DFOM) and acetylsalicylic acid (AC), respectively. The excellent photothermal effect of MNFs@DFOM-H@AC could better meet the complicated needs for accurate healing wounds. Importantly, two factors integrated their respective advantages for wound healing without scarring. Moreover, the photothermal effect can regulate effectively control DFOM release, meanwhile without harming the skin, to effectively limit excessive angiogenesis. Additionally, AC released from the hydrogel can regulate the immune micro-environment at the wound site, and achieve anti-inflammatory and appropriate vascularization. Therefore, we believe that the prepared double structure system has promising application in wound healing field.

Type III effectors secreted by rhizobia regulate nodulation in the host plant and are important modulators of symbiosis between rhizobia and soybean (Glycine max), although the underlying mechanisms are poorly understood. Here, we studied the type III effector NopAA in Sinorhizobium fredii HH103, confirming its secretion into the extracellular environment under the action of genistein. The enzyme activity of NopAA was investigated in vitro, using xyloglucan and β-glucan as substrates. NopAA functions were investigated by the generation of a NopAA mutant and the effects of NopAA deficiency on symbiosis were analyzed. Soybean genes associated with NopAA were identified in a recombinant inbred line (RIL) population and their functions were verified. NopAA was confirmed to be a type III effector with glycosyl hydrolase activity, and its mutant did not promote nodulation. Quantitative trait locus (QTL) analysis identified 10 QTLs with one, Glyma.19g074200 (GmARP), found to be associated with NopAA and to positively regulate the establishment of symbiosis. All these results support the hypothesis that type III effectors interact with host proteins to regulate the establishment of symbiosis and suggest the possibility of manipulating the symbiotic soybean–rhizobia interaction to promote efficient nitrogen fixation.

Abstract Diffusion-driven instability is a basic nonlinear mechanism for pattern formation. Therefore, the way of population diffusion may play a determinative role in the spatiotemporal dynamics of biological systems. In this research, we launch an investigation on the pattern formation of a discrete predator–prey system where the population diffusion is based on the Moore neighborhood structure instead of the von Neumann neighborhood structure widely applied previously. Under pattern formation conditions which are determined by Turing instability analysis, numerical simulations are performed to reveal the spatiotemporal complexity of the system. A pure Turing instability can induce the self-organization of many basic types of patterns as described in the literature, as well as new spiral-spot and labyrinth patterns which show the temporally oscillating and chaotic property. Neimark–Sacker–Turing and flip–Turing instability can lead to the formation of circle, spiral and much more complex patterns, which are self-organized via spatial symmetry breaking on the states that are homogeneous in space and non-periodic in time. Especially, the emergence of spiral pattern suggests that spatial order can generate from temporal disorder, implying that even when the predator–prey dynamics in one site is chaotic, the spatially global dynamics may still be predictable. The results obtained in this research suggest that when the way of population diffusion changes, the pattern formation in the predator–prey systems demonstrates great differences. This may provide realistic significance to explain more general predator–prey coexistence.

The effects of chlorogenic acid (CGA) on growth performance, anticoccidial indicators (oocysts per gram of excreta, cecal lesion score, and bloody diarrhea score), immunity, antioxidant status, and intestinal barrier function in coccidia-infected broilers were investigated. A total of 240 one-day-old Arbor Acres broilers were randomly divided into four groups with six replicates of ten broilers each for 42 days. Four treatments included control diet (non-infected control, NC), control diet +Eimeria infection (infected control, IC), control diet +0.5 g/kg CGA + Eimeria infection (CGA0.5), and control diet +1 g/kg CGA + Eimeria infection (CGA1). At day 14, each broiler in IC, CGA0.5, and CGA1 groups was orally inoculated with 1 mL saline containing 4 × 105 sporulated oocysts. The results showed that the CGA1 group increased the average daily gain by 12.57% (p < 0.001) and decreased the feed/gain ratio (p = 0.010) and mortality (p = 0.030) by 13.00% and 77.76%, respectively, of broilers from 14 to 42 days compared with the IC group. The CGA1 group decreased the oocysts per gram of excreta (p < 0.001) and bloody diarrhea score (p = 0.001) compared with the IC group. The CGA0.5 and CGA1 groups increased total antioxidant capacity (p < 0.001) at day 21 and villus height (p < 0.001) in the duodenum and jejunum at day 42, and decreased the levels of interleukin 6 (IL-6) (p = 0.002), malondialdehyde (MDA) (p < 0.001), D-lactic acid (p < 0.001), and diamine oxidase (DAO) (p < 0.001) at day 21 and the levels of MDA (p < 0.001) and D-lactic acid (p = 0.003) at day 42 compared with the IC group. In the CGA1 group, villus height in the duodenum (p < 0.001) and jejunum (p = 0.017) increased at day 21 and in the ileum (p < 0.001) at day 42, and the level of DAO (p < 0.001) decreased at day 42 compared with the IC group. Broilers in the IC group had a higher IL-6 level (p = 0.048) at day 42 and lower IL-10 (p = 0.027) and immunoglobulin A (p = 0.042) levels at day 21, and IL-10 level (p = 0.017) at day 42 than those in the NC group, while no significant differences were observed among the NC, CGA0.5, and CGA1 groups. In conclusion, dietary supplementation with 1 g/kg CGA improved growth performance, immunity, antioxidant status, and intestinal barrier function in coccidia-infected broilers.

Multimodality optical imaging probes have emerged as powerful tools that improve detection sensitivity and accuracy, important in disease diagnosis and treatment. In this review, we focus on recent developments of optical fluorescence imaging (OFI) probe integration with other imaging modalities such as X-ray computed tomography (CT), magnetic resonance imaging (MRI), positron emission tomography (PET), single-photon emission computed tomography (SPECT), and photoacoustic imaging (PAI). The imaging technologies are briefly described in order to introduce the strengths and limitations of each techniques and the need for further multimodality optical imaging probe development. The emphasis of this account is placed on how design strategies are currently implemented to afford physicochemically and biologically compatible multimodality optical fluorescence imaging probes. We also present studies that overcame intrinsic disadvantages of each imaging technique by multimodality approach with improved detection sensitivity and accuracy. KEY WORDS: Optical imaging, Fluorescence, Multimodality, Near-infrared fluorescence, Nanoprobe, Computed tomography, Magnetic resonance imaging, Positron emission tomography, Single-photon emission computed tomography, Photoacoustic imaging

Abstract A spatiotemporal discrete predator–prey system is investigated for understanding the pattern self-organization on the route to chaos. The discrete system is modelled by a coupled map lattice and shows advection of populations in space. Based on the conditions of stable stationary states and Hopf bifurcation, Turing pattern formation conditions are determined. As the parameter value is changed, self-organization of diverse patterns and complex phase transition among the patterns on the route to chaos are observed in simulations. Ordered patterns of stripes, bands, circles, and various disordered states are revealed. When we zoom in to observe the pattern transition in smaller and smaller parameter ranges, subtle structures for transition process are found: (1) alternation between self-organized structured patterns and disordered states emerges as the main nonlinear characteristic; (2) when the parameter value varies in the level from 10−3 to 10−4, a cyclic pattern transition process occurs repeatedly; (3) when the parameter value shifts in the level of 10−5 or below, stochastic pattern fluctuation dominates as essential regularity for pattern variations. The results obtained in this research promote comprehending pattern self-organization and pattern transition on the route to chaos in spatiotemporal predator–prey systems.

The nonlinear dynamics of predator-prey systems coupled into network is an important issue in recent biological advances. In this research, we consider each node of the coupled network represents a discrete predator-prey system, and the network dynamics is investigated. By applying Jacobian matrix, center manifold theorem and bifurcation theorems, stability of fixed points, flip bifurcation and Neimark-Sacker bifurcation of the discrete predator-prey system are analyzed. Via the method of Lyapunov exponents, the nonchaos-chaos transition of the coupled network along the routes to chaos induced by bifurcations is determined. Numerical simulations are performed to demonstrate the bifurcations, various attractors and dynamic transitions of the coupled network. Via comparison, we find that the coupled network exhibits far richer and more complex behaviors than single predator-prey system, including period-doubling cascades in orbits of period-2, period-4, period-8, invariant closed curves, dynamic windows for periodic orbits and invariant curves, quasiperiodic orbits, tori, and chaotic sets. Moreover, the attractors of the coupled network show more diverse and complicated structures. These results may provide a new perspective on the predator-prey dynamics in complex networks.

We present in this paper an investigation on a discrete predator-prey system with Crowley-Martin type functional response to know its complex dynamics on the routes to chaos which are induced by bifurcations. Via application of the center manifold theorem and bifurcation theorems, occurrence conditions for flip bifurcation and Neimark-Sacker bifurcation are determined, respectively. Numerical simulations are performed, on the one hand, verifying the theoretical results and, on the other hand, revealing new interesting dynamical behaviors of the discrete predator-prey system, including period-doubling cascades, period-2, period-3, period-4, period-5, period-6, period-7, period-8, period-9, period-11, period-13, period-15, period-16, period-20, period-22, period-24, period-30, and period-34 orbits, invariant cycles, chaotic attractors, sub-flip bifurcation, sub-(inverse) Neimark-Sacker bifurcation, chaotic interior crisis, chaotic band, sudden disappearance of chaotic dynamics and abrupt emergence of chaos, and intermittent periodic behaviors. Moreover, three-dimensional bifurcation diagrams are utilized to study the transition between flip bifurcation and Neimark-Sacker bifurcation, and a critical case between the two bifurcations is found. This critical bifurcation case is a combination of flip bifurcation and Neimark-Sacker bifurcation, showing the nonlinear characteristics of both bifurcations.

A spatiotemporal discrete predator-prey system with Allee effect is investigated to learn its Neimark-Sacker-Turing instability and pattern formation. Based on the occurrence of stable homogeneous stationary states, conditions for Neimark-Sacker bifurcation and Turing instability are determined. Numerical simulations reveal that Neimark-Sacker bifurcation triggers a route to chaos, with the emergence of invariant closed curves, periodic orbits, and chaotic attractors. The occurrence of Turing instability on these three typical dynamical behaviors leads to the formation of heterogeneous patterns. Under the effects of Neimark-Sacker-Turing instability, pattern evolution process is sensitive to tiny changes of initial conditions, suggesting the occurrence of spatiotemporal chaos. With application of deterministic initial conditions, transient symmetrical patterns are observed, demonstrating that ordered structures can exist in chaotic processes. Moreover, when local kinetics of the system goes further on the route to chaos, the speed of symmetry breaking becomes faster, leading to more fragmented and more disordered patterns at the same evolution time. The rich spatiotemporal complexity provides new comprehension on predator-prey coexistence in the ways of spatiotemporal chaos.

Wind-induced vegetation patterns were proposed a long time ago but only recently a dynamic vegetation-sand relationship has been established. In this research, we transformed the continuous vegetation-sand model into a discrete model. Fixed points and stability analyses were then studied. Bifurcation analyses are done around the fixed point, including Neimark-Sacker and Turing bifurcation. Then we simulated the parameter space for both bifurcations. Based on the bifurcation conditions, simulations are carried out around the bifurcation point. Simulation results showed that Neimark-Sacker bifurcation and Turing bifurcation can induce the self-organization of complex vegetation patterns, among which labyrinth and striped patterns are the key results that can be presented by the continuous model. Under the coupled effects of the two bifurcations, simulation results show that vegetation patterns can also be self-organized, but vegetation type changed. The type of the patterns can be Turing type, Neimark-Sacker type, or some other special type. The difference may depend on the relative intensity of each bifurcation. The calculation of entropy may help understand the variance of pattern types.

The formation of self-organized patterns in predator-prey models has been a very hot topic recently. The dynamics of these models, bifurcations and pattern formations are so complex that studies are urgently needed. In this research, we transformed a continuous predator-prey model with Lesie-Gower functional response into a discrete model. Fixed points and stability analyses were studied. Around the stable fixed point, bifurcation analyses including: flip, Neimark-Sacker and Turing bifurcation were done and bifurcation conditions were obtained. Based on these bifurcation conditions, parameters values were selected to carry out numerical simulations on pattern formation. The simulation results showed that Neimark-Sacker bifurcation induced spots, spirals and transitional patterns from spots to spirals. Turing bifurcation induced labyrinth patterns and spirals coupled with mosaic patterns, while flip bifurcation induced many irregular complex patterns. Compared with former studies on continuous predator-prey model with Lesie-Gower functional response, our research on the discrete model demonstrated more complex dynamics and varieties of self-organized patterns.

[Objectives] To explore the evolution of the legal system of farmland protection and explore the rules and characteristics of policy development based on the theory and logic of institutional change since China's reform and opening up, reveal the problems and deep-seated reasons of its legislation, clarify the direction of farmland protection in the new period, and solve the "non-agricultural" "non-grain" and ecological problems of farmland. [Methods] Literature analysis and inductive deduction methods were used. [Results] The evolution of the farmland protection legal system has gone through the process of "national consciousness-policy guidelines-institutional system", the change from "single subject to multiple subjects"; change from the use of "one-way administrative means to coordinated use of administrative, economic and technical means". The practical problems of the farmland protection legal system are mainly due to the insufficient systematization of the farmland protection legal system itself, the generalization of quantity protection, the transformation of quality protection, and the absence of ecological protection. [Conclusions] It is recommended to improve the existing farmland protection legal system from the establishment of the Farmland Protection Law, the improvement of the farmland protection public participation mechanism and supervision mechanism, the establishment of the farmland quality construction and improvement system, the differentiated farmland occupation and supplementation balance system, and the ecological restoration system. [ABSTRACT FROM AUTHOR]