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Highlights: A flexible tribotronic artificial synapse with bioinspired neurosensory behaviour was demonstrated, which establishes an active interaction mechanism with the environment. The device can well exhibit tuneable synaptic behaviours by changing the mechanical input modes, including excitatory postsynaptic current, paired-pulse facilitation, and the hierarchical memorial process. The device has excellent mechanical flexibility that can exhibit stable synaptic functions even under strain conditions with a bending radius of 20 mm after 1000 bending cycles. As key components of artificial afferent nervous systems, synaptic devices can mimic the physiological synaptic behaviors, which have attracted extensive attentions. Here, a flexible tribotronic artificial synapse (TAS) with bioinspired neurosensory behavior is developed. The triboelectric potential generated by the external contact electrification is used as the ion-gel-gate voltage of the organic thin film transistor, which can tune the carriers transport through the migration/accumulation of ions. The TAS successfully demonstrates a series of synaptic behaviors by external stimuli, such as excitatory postsynaptic current, paired-pulse facilitation, and the hierarchical memory process from sensory memory to short-term memory and long-term memory. Moreover, the synaptic behaviors remained stable under the strain condition with a bending radius of 20 mm, and the TAS still exhibits excellent durability after 1000 bending cycles. Finally, Pavlovian conditioning has been successfully mimicked by applying force and vibration as food and bell, respectively. This work demonstrates a bioinspired flexible artificial synapse that will help to facilitate the development of artificial afferent nervous systems, which is great significance to the practical application of artificial limbs, robotics, and bionics in future. [ABSTRACT FROM AUTHOR]

• An intrinsically stretchable tribotronic mechanoplastic artificial synapse was proposed. • The device can be modulated by the triboelectric potential induced by mechanical stimulation. • The device establishes an active mechanically adjustable synaptic plasticity. Stretchable synaptic devices with adaptability to elastic deformation, sensing environmental stimuli, and unique information processing functions are of great significance for the development of the next generation of artificial nervous systems. Here, an intrinsically stretchable tribotronic mechanoplastic artificial synapse (STMAS) is proposed, which is integrated by a triboelectric nanogenerator and an electrolyte-gated transistor with ion-gel as dielectric layer. The STMAS can be modulated by the triboelectric potential induced by mechanical stimulation without the need to apply an external gate voltage, achieving an active mechanical tuning of synaptic plasticity such as excitatory postsynaptic current, paired-pulse facilitation, short-term plasticity, and long-term plasticity. The STMAS exhibits stable synaptic plasticity under 0–50% stretcher strain in parallel and vertical to channel directions, respectively. Furthermore, the International Morse code triggered by mechanical signals has been successfully mimicked. This work has achieved an intrinsically stretchable tribotronic artificial synapse with mechanically tuned synaptic behavior, which will help promote the development of artificial nervous systems and expand the applications of artificial synapses in intelligent robotics, artificial limbs and human–machine interaction. [ABSTRACT FROM AUTHOR]

Secondary cooling electromagnetic stirring (S-EMS) significantly impacts the internal quality of continuous casting slabs. In order to investigate the effects of S-EMS modes on segregation in slabs, a three-dimensional numerical model of the full-scale flow field, solidification, and mass transfer was established. A comparative analysis was conducted between continuous electromagnetic stirring and alternate stirring modes regarding their impacts on steel flow, solidification, and carbon segregation. The results indicated that adopting the alternate stirring mode was more advantageous for achieving uniform flow fields and reducing the disparity in solidification endpoints, thus mitigating carbon segregation. Specifically, the central carbon segregation index under continuous stirring at 320 A was 1.236, with an average of 1.247, while under alternate stirring, the central carbon segregation index decreased to 1.222 with an average of 1.227. [ABSTRACT FROM AUTHOR]

Self-trapped modes suffer critical collapse in two-dimensional cubic systems. To overcome such a collapse, linear periodic potentials or competing nonlinearities between self-focusing cubic and self-defocusing quintic nonlinear terms are often introduced. Here, we combine both schemes in the context of an unconventional and nonlinear fractional Schrödinger equation with attractive-repulsive cubic–quintic nonlinearity and an optical lattice. We report theoretical results for various two-dimensional trapped solitons, including fundamental gap and vortical solitons as well as the gap-type soliton clusters. The latter soliton family resembles the recently-found gap waves. We uncover that, unlike the conventional case, the fractional model exhibiting fractional diffraction order strongly influences the formation of higher band gaps. Hence, a new route for the study of self-trapped modes in these newly emergent higher band gaps is suggested. Regimes of stability and instability of all the soliton families are obtained with the help of linear-stability analysis and direct simulations. Stabilising localised solitons in higher dimensions is more challenging than their one dimensional counterpart due to the onset of critical collapse. Here, competing nonlinear terms are added to a linearly-modulated optical lattice to predict regimes of stability for different soliton families. [ABSTRACT FROM AUTHOR]

Gas pressure is one of the major factors to characterize the outburst danger of coal seams. Generally, the process of gas pressure determination is complicate and cannot ensure the accuracy of results, which may cause a wrong identification of outburst danger. This paper discussed and revealed a positive correlation between initial gas emission and gas pressure, which provides a new approach to identify the outburst danger by initial gas emission. Through theoretical analysis and numerical simulation, the liner equation of gas pressure and initial gas emission was deduced. Laboratory experiments under adsorption and desorption of CO2 and N2 were performed using coal samples from Weishe coal mine. The data of initial gas emission under different gas pressure were recorded, and the fitting curves were obtained. The results show a positive correlation between initial gas emission and gas pressure, and the curve of N2 was below the CO2. Especially, while the adsorption gas pressure was under 0.663 and 0.675 MPa, the difference of corresponding initial gas emission was only 0.01 L/s, which indicates the high degree of correlation. The results validated the theoretical and practical feasibility to identify the coal and the gas outbursts through initial gas emission. [ABSTRACT FROM AUTHOR]

Eucommia ulmoides Oliver seed oil, rich in polyunsaturated fatty acids (PUFAs), is susceptible to lipid oxidation in foods. Tea polyphenols (TPs) may effectively retard lipid oxidation in non-polar systems according to the polar paradox theory. In this study, we constructed a TPs-loaded water-in oil (W/O) microemulsion, which is a transparent, spontaneously formed, and thermodynamically stable colloidal system. This system consisted of E. ulmoides oil (38%, w/w), Span80, Tween 80, 1,2 propanediol, water, and TPs (3%, w/w). TPs were encapsulated in water cores of microemulsion, endowing this system with the higher oxidative stability and radical scavenging abilities. The accelerated oxidation assay demonstrated that low-dose TPs (<0.5%, w/w) were more effective in retarding lipid oxidation than that of high-dose TPs. Within 56 d, the peroxide value of TPs-loaded microemulsion increased to 16.479 meq/kg oil at 65 ℃ and that of E. ulmoides oil exceeded the Food Safety standards value within only 45 d. These findings indicate that TPs encapsulated into microemulsion effectively inhibit PUFA-rich oil oxidation. The nano-scale W/O dispersed system favors the protection and practical application of natural water-soluble antioxidants in PUFAs-rich lipid foods. [Display omitted] • TPs- E. ulmoides oil microemulsion was designed to allow sufficient dispersion of a polar antioxidant. • The system has nano-sized reverse micelles and excellent physicochemical stability. • This system can efficiently retard lipid oxidation and scavenge free radicals. [ABSTRACT FROM AUTHOR]

The heat transfer of a slab is significantly influenced by roll contact during the continuous casting process. The influence of roll contact calculation methods on the predicted heat transfer results has not been previously investigated. In this work, the non-uniform solidification of the wide-thick slab was studied with a 2D heat transfer model using real roll contact method (R. method) and equivalent roll contact method (E. method). The predicted slab surface temperature and shell thickness were verified with the measured results of the infrared camera and nail shooting experiments, respectively. Then, the predicted heat transfer results (including the slab surface temperature, mushy region length, and solidification end position) for the wide-thick slab with different thicknesses and different casting speeds were calculated using the E. method and R. method, and the influence of these two roll contact methods on the predicted heat transfer results was discussed for the first time. The results show that both these two roll contact methods could be applied to accurately predict the slab surface temperature without considering the transient temperature dips in the roll–slab contact regions. However, the deviation of the predicted mushy region length and solidification end position using the E. method are obvious. Compared with the R. method, the predicted mushy region length obtained using the E. method is larger and the solidification end obviously subsequently moves along the casting direction. [ABSTRACT FROM AUTHOR]

Recent years have witnessed a staggering escalation in the power density of modern electronic devices. Because increasingly high power density accumulates heat, efficient heat removal has become a critical limitation for the performance, reliability, and further development of modern electronic devices. Thermal interface materials (TIMs) are widely employed between the two solid contact surfaces of heat sources and heat sinks to increase heat removal for electric devices. Composites of graphene and matrix materials are expected to be the most promising TIMs because of the remarkable thermal conductivity of graphene. Here, the recent research on the thermal properties of graphene filled polymer composite TIMs is reviewed. First, the composition of graphene filled polymer composite TIMs is introduced. Then, the synthetic methods for graphene filled polymer composite TIMs are primarily described. This study focuses on introducing the methods for improving and characterizing the thermal properties of graphene filled polymer composite TIMs. Furthermore, the challenges facing graphene filled poly­mer composite TIMs for thermal management applications in the modern electronic industry and the further progress required in this field are discussed. [ABSTRACT FROM AUTHOR]

Arginine methylation is a common post-translational modification and is critical for many cellular processes. Sfm1 is a novel arginine methyltransferase that contains a SpoU-TrmD ( SPOUT) domain, a typical fold known for RNA methylation, but acts on a ribosomal protein. The underlying mechanism is poorly understood. Here, we report cocrystal structures of Sfm1 in complex with various ligands. We found that a critical loop responsible for S-adenosyl- l-methionine ( SAM) binding adopts a different conformation from previous reports, and SAM appears to exhibit double conformations. Deletion of this loop greatly reduces the affinity of Sfm1 to SAM. Additionally, by comparison to closely related tRNA-methyltransferase Trm10, our structural analyses offer a good explanation why the two enzymes utilize distinct substrates, providing insights into the molecular mechanism. [ABSTRACT FROM AUTHOR]

The wearable tactile sensors have attracted great attention in the fields of intelligent robots, healthcare monitors and human-machine interactions. To create active tactile sensors that can directly generate electrical signals in response to stimuli from the surrounding environment is of great significance. Triboelectric nanogenerators (TENGs) have the advantages of high sensitivity, fast response speed and low cost that can convert any type of mechanical motion in the surrounding environment into electrical signals, which provides an effective strategy to design the self-powered active tactile sensors. Here, an overview of the development in TENGs as tactile stimulators for multifunctional sensing and artificial synapses is systematically introduced. Firstly, the applications of TENGs as tactile stimulators in pressure, temperature, proximity sensing, and object recognition are introduced in detail. Then, the research progress of TENGs as tactile stimulators for artificial synapses is emphatically introduced, which is mainly reflected in the electrolyte-gate synaptic transistors, optoelectronic synaptic transistors, floating-gate synaptic transistors, reduced graphene oxides-based artificial synapse, and integrated circuit-based artificial synapse and nervous systems. Finally, the challenges of TENGs as tactile stimulators for multifunctional sensing and artificial synapses in practical applications are summarized, and the future development prospects are expected. [ABSTRACT FROM AUTHOR]

Ultrasonic technology is often used to modify proteins. Here, we investigated the effects of ultrasound alone or in combination with other heating methods on emulsifying properties and structure of glycinin (11S globulin). Structural alterations were assessed with Sodium dodecyl sulphate-polyacrylamide gel electrophoresis (SDS–PAGE), intrinsic fluorescence spectroscopy, ultraviolet (UV) absorption spectroscopy, and Fourier transform infrared (FTIR) spectroscopy. The size distribution and zeta-potential of 11S globulin were evaluated with a particle size analyzer. An SDS-PAGE analysis showed no remarkable changes in the primary structure of 11S globulin. Ultrasound treatment disrupted the 11S globulin aggregates into small particles with uniform size, narrowed their distribution and increased their surface charge density. Fluorescent spectroscopy and second-derivative UV spectroscopy revealed that ultrasound coupled with heating induced partial unfolding of 11S globulin, increasing its flexibility and hydrophobicity. FTIR further showed that the random coil and α-helix contents were higher while β-turn and β-sheet contents were lower in ultrasound combined with heating group compared to the control group. Consequently, the oil-water interface entirely distributed protein and reduced the surface tension. Moreover, ultrasound combined with heating at 60 °C increased the emulsifying activity index and emulsifying stability index of 11S globulins by 6.49-folds and 2.90-folds, respectively. These findings suggest that ultrasound combined with mild heating modifies the emulsification properties of 11S globulin. [ABSTRACT FROM AUTHOR]

Ubiquitin E3 Ligase MARCH7 is involved in T cell proliferation and neuronal development. In our previous study, we demonstrated MARCH7 promoted malignant behavior of ovarian cancer via the nuclear factor (NF)-κB and Wnt/β-catenin signaling pathway. However, the expression and function of MARCH7 in cervical cancer remains unknown. The present study aimed to unravel the expression and function of MARCH7 in cervical cancer to elucidate its potential role in the diagnosis and pathogenesis of cervical cancer. Results indicated that the expression of MARCH7 was abnormally high in cervical cancer tissues than normal cervical tissues. However, silencing the expression of MARCH7 in HeLa cells resulted in decreased cell proliferation and invasion. Mechanistic investigations revealed that MARCH7 interacted with VAV2. Silencing the expression of MARCH7 in HeLa cells inhibited the VAV2-RAC1-CDC42 signaling pathway. Overall, the results of the present study identified MARCH7 as a candidate oncogene in cervical cancer, and a potential target for cervical cancer therapy. [ABSTRACT FROM AUTHOR]

The wyosine derivatives present at position 37 in transfer RNAs (tRNAs) are critical for reading frame maintenance. The methyltransferase Trm5a from Pyrococcus abyssi (PaTrm5a) plays a key role in this hypermodification process in generating m1G37 and imG2, two products of the wyosine biosynthetic pathway, through two methyl transfers to distinct substrates, but the mechanism is currently unknown. We report two cocrystal structures of PaTrm5a in complex with tRNAPhe and reveal the structural basis for substrate recognition, which was supported by in vitro activity assays. The crystal structures showed that the D1 domain of the enzyme undergoes large conformational changes upon the binding of tRNA. The deletion of this domain greatly reduces the affinity and activity of PaTrm5a toward its RNA substrate, indicating that the enzyme recognizes the overall shape of tRNA. Using the small-angle x-ray scattering technique and crystallographic analysis, we discovered that PaTrm5a adopts distinct open conformations before and after the binding of tRNA. Last, through structure comparison with its ortholog Methanococcus jannaschii Trm5b (MjTrm5b), we propose a reaction mechanism for the double methylation capability of this unique enzyme. [ABSTRACT FROM AUTHOR]

Background. Cervical cancer (CC) is one of the most frequent female malignancy. Cancer stem cells (CSCs) positively affect survival outcomes in cancer patients, but in cervical cancer, the mechanism of tumor stem cells is still uncertain. Methods. RNA-seq data and related clinical follow-up of patients suffering from CC were from TCGA. Consensus clustering screened prognostic mRNAsi-related genes and identified molecular subtypes for CC. Based on the overlapping differentially expressed genes (DEGs) in subtypes, we employed LASSO and multivariate Cox regression to screen prognostic-related genes and established the RiskScore system. The patients were grouped by RiskScore, the prognosis was analyzed by the Kaplan-Meier (K-M) curve among the various groups, and the precision of the RiskScore was assessed by the ROC curve. Finally, the potential worth of RiskScore in immunotherapy/chemotherapy response was assessed by evaluating TIDE scores and chemotherapy drug IC 50 values. Results. We noticed that patients with low mRNAsi had a shorter survival and then identified three molecular subtypes (C1-3), with the C1 having the worst prognosis and the lowest mRNAsi. Finally, we identified 7 prognostic-related genes (SPRY4, PPP1R14A, MT1A, DES, SEZ6L2, SLC22A3, and CXCL8) via LASSO and Cox regression analysis. We established a 7-gene model defined RiskScore to predict the prognosis of CC patients. K-M curve indicated that low RiskScore patients had improved prognosis, and ROC curves indicated that RiskScore could precisely direct the prognostic evaluation for those suffering from the cancer. This was also confirmed in the GSE44001 and GSE52903 external cohorts. Patients were more sensitive to immunotherapy if with low RiskScore, and RiskScore exhibited precise assessment ability in predicting response to immunological therapy in CC patients. Conclusion. CC stemness is associated with patient prognosis, and the RiskScore constructed based on stemness characteristics is an independent prognostic index, which is expected to be a guide for immunotherapy, providing a new idea for CC clinical practice. [ABSTRACT FROM AUTHOR]

This paper describes the preparation of low-temperature sintered nanosilver paste with inverse microemulsion method with Span-80/Triton X-100 as the mixed-surfactant and analyzes the influence of different sintering parameters (temperature, pressure) on the shear properties of low-temperature sintering of nanosilver. Experimental results show that the shear strength of the low-temperature sintering of nanosilver increases as the temperature and pressure increase. But there are many pores and relative fewer cracks on the sintering layer after low-temperature sintered. The test thermal resistance of low-temperature sintered nanosilver paste is 0.795 K/W which is greater than SAC305 weld layer with a T3ster thermal analyzer. The adhesive performance and the heat dispersion of low-temperature sintered nanosilver paste need to be further researched and improved. [ABSTRACT FROM AUTHOR]

Based on the coupling effect of contact electrification and electrostatic induction, the triboelectric nanogenerator (TENG) as an emerging energy technology can effectively harvest mechanical energy from the ambient environment. However, due to its inherent property of large impedance, the TENG shows high voltage, low current and limited output power, which cannot satisfy the stable power supply requirements of conventional electronics. As the interface unit between the TENG and load devices, the power management circuit can perform significant functions of voltage and impedance conversion for efficient energy supply and storage. Here, a review of the recent progress of switching power management for TENGs is introduced. Firstly, the fundamentals of the TENG are briefly introduced. Secondly, according to the switch types, the existing power management methods are summarized and divided into four categories: travel switch, voltage trigger switch, transistor switch of discrete components and integrated circuit switch. The switch structure and power management principle of each type are reviewed in detail. Finally, the advantages and drawbacks of various switching power management circuits for TENGs are systematically summarized, and the challenges and development of further research are prospected. [ABSTRACT FROM AUTHOR]

Power management is an efficacious route to promote the development of triboelectric nanogenerators (TENGs), in which the buck switch for efficient energy extraction has always been a challenge. Here, we propose a three-port cantilever buck switch which can autonomously release energy from the TENG in maximum by the generated electrostatic field of the TENG. The influence of closing voltage of the buck switch on different structure parameters has been thoroughly investigated. The U-Q curve indicates that the optimal energy extraction can reach 90.86%, and the matched impedance of the TENG is reduced from 60 MΩ to 470 kΩ. Compared to the output power at matched impedance, the average power managed by this three-port cantilever buck switch is increased by 1.554 times, which can power the Bluetooth device, electronic watch, calculator and thermo-meter. This work has realized ultra-efficient power management of TENG by leveraging an autonomous cantilever buck switch, which can contribute to the efficient utilization of micromechanical energy. • A three-port cantilever buck switch controlled by the electrostatic field of the TENG for its power management is pioneered. • A detailed analysis of the force-electricity conversion process has been conducted. • U-Q curve and P-R curve has been linked to characterize the output efficiency for the first time. [ABSTRACT FROM AUTHOR]

The gas emission rate of boreholes is one of the most important indices for coal and gas outburst prediction. In this work, instantaneous gas emission velocity and environmental effects on borehole gas emission were studied. Through theoretical analysis, the mechanism of crack propagation in the coal borehole was clarified, and the effect of soft and hard coal on gas desorption and gas emission. The results of numerical simulations also indicated that the initial gas emission has a function relationship to the drilling distance and the physical characteristics of the coal seam. A novel dynamic testing technology was proposed to obtain gas emission velocity. Laboratory experiments under adsorption and desorption of CO2 and N2 were performed using coal samples from Xuehu, Fenghui, Weishe, and Wuzhong coal mines. The data of initial gas emission under different coal samples were recorded, and the fitting curves were obtained. The results show a positive correlation between initial gas emission and drilling depth. However, abnormal would occur when the drill pipe enters the soft stratification, and the maximum value of the initial gas emission of the abnormal part is 3.8 times the normal value, which indicates a high degree of sensibility to soft stratification. The results were revealed the dynamic gas emission law of boreholes. [ABSTRACT FROM AUTHOR]

[Display omitted] • P. chrysosporium could tolerate IMI and transform 93.5% for 6 days. • Manganese and lignin peroxidase played important roles in IMI transformation. • IMI mainly underwent nitrate-reduction, hydroxylation, and de-chlorination process. • MD results explained the reactive sites and metabolic mechanisms of enzymes. • 6-chloronicotinic acid, a less neurologically toxic major metabolite, was detected. As one of the widely used neonicotinoid insecticide, imidacloprid (IMI) poses serious threat on many kinds of non-target species. The acceleration of its removal from the contaminated environment is therefore an urgent task. Herein, the transformation of IMI by white-rot fungus Phanerochaete chrysosporium was examined, and the reaction mechanism underlying enzymes-mediated IMI biotransformation was elucidated. In addition, transformed products, pathways, and toxicity to Escherichia coli and Microcystis aeruginosa or the growth of rice seeds were investigated. P. chrysosporium could efficiently transform 93.5% of IMI for 6 days primarily through biotransformation, in which extracellular manganese peroxidase and lignin peroxidase substantially responded to transform IMI. IMI mainly underwent nitrate reduction, hydroxylation, and de-chlorination. A less neurologically toxic major metabolite of IMI, 6-chloronicotinic acid, was detected. Molecular dynamics simulation demonstrated that IMI stably bonded to active pocket of extracellular enzymes. This study reveals the key metabolic mechanism and fate of IMI in environment, and highlights the potential of fungi for IMI transformation. [ABSTRACT FROM AUTHOR]

Polymer composites of highly effective thermal conductivity (ETC) are commonly used in various industries, for renewable energy systems and Electronic Systems. Owing to the low thermal conductivity (TC) of polymers, inserting particles with ultra-high TC into the polymer matrix makes it possible for polymer composites to possess high ETC. The ETC of polymer composites is determined by several factors, including the particle and matrix properties and microscopic structures. Modelling methods are powerful tools to understand how these factors influence the ETC of polymer composites. Modelling methods can be combined with experimental data and can be used to qualitatively and quantitatively analyse the impact of various factors on the ETC. Moreover, modelling methods can be used as a guide for the choice and design of particle-filled composites for engineering applications. Herein, we review the recent research on ETC models of polymer composites. First, the classical theoretical models of ETC for polymer composites are introduced. Then, novel theoretical and simulation models are described. We focus on the influence of the theoretical models and the simulation models of polymer composites at multiple scales. Finally, we conclude and give an outlook regarding the ETC models of polymer composites. [ABSTRACT FROM AUTHOR]

A compact, springless, easy-to-process kirigami-inspired TENG (KI-TENG) is developed. The frequency responses of the KI-TENG under the influence of mass, acceleration, and initial distance are investigated in detail to optimize its structural design. Moreover, the TENG coupled with the kirigami structure could collect ultra-wide-band vibration energy and as a sensor measuring acceleration. [Display omitted] • A compact and springless kirigami-inspired TENG (KI-TENG) is developed. • The frequency response characteristics of the KI-TENG are investigated. • The KI-TENG can harvest ultra-wide-band vibration energy from 2 to 49 Hz. • The output of the KI-TENG at different vibration tilt angles is explored. • The KI-TENG can effectively monitor acceleration changes from 1 to 9 m/s2. Triboelectric Nanogenerators (TENGs) based on spring-assisted structures play a central role in scavenging vibrational energy that is widely available in the natural environment. However, they suffer from difficulties in adjusting the stiffness and bonding the springs to the triboelectric layer. Here, a kirigami-inspired TENG (KI-TENG) with a kirigami structure is demonstrated, which can be used as an ultra-wide-band vibrational energy harvester and self-powered acceleration sensor. The triboelectric layer of the KI-TENG can be easily processed into the kirigami structure with one or two-degree-of-freedom by laser cutting technology. The frequency responses of the KI-TENG under the influence of mass, acceleration, and initial distance are investigated in detail to optimize the structural design. With optimized structural parameters, the KI-TENG can not only harvest broadband vibration energy from 2 to 49 Hz in vertical vibration state but also obtain high output performance over a wide frequency range in horizontal vibration state. Moreover, the KI-TENG can be used as a sensor measuring acceleration from 1 to 9 m/s2. This work demonstrates a compact TENG coupled with the kirigami structure for energy harvesting and active sensing, which has great prospects in intelligent plants, artificial intelligence, and the internet age. [ABSTRACT FROM AUTHOR]

In China, indigenous pigs are popular due to their excellent meat quality and unique flavor. In this study, the unique flavor was investigated using Guangdong small-ear spotted pig (GD) and their hybrid progeny, which produced high-end pork in the Chinese market. Two-dimensional gas chromatography-time-of-flight mass spectrometry (GC × GC-TOF MS) was used to analyze and quantify volatile organic compounds (VOCs) in the two pork types for identifying the unique flavor of these very popular pigs. The flavor is imparted by alkanes, aldehydes, ketones, and ethers. Flavor imparting compounds mainly include methyl isobutyl ketone, octane, pentane, and 3-ethyl-2, 2-dimethylheptane. High levels of volatilization of such compounds generated ethereal, acetonic, sweet, and green odors in the pork of GD. Hybrid offspring of Chinese and Western pig breeds can also inherit such special aromas, which are sometimes even more intense, with increased meat yield. Multi-omics analysis of the transcriptome and metabolome showed that AMD1 (Adenosylmethionine Decarboxylase 1) affects the p-cresol content by regulating the polyamine pathway, affecting the unique flavor of GD. This study revealed the unique flavor composition of GD, analyzed the advantages of species hybridization, and thus, provides a new direction and theoretical basis for pork quality improvement. • Identification of volatile organic compounds in Guangdong small-ear spotted pig. • Application of GC × GC-TOF MS to flavor of different types pork. • Multiple metabolome omics association analysis for Guangdong small-ear spotted pig. • Pork flavor identification for Chinese and Western pig breeds hybrid offspring. [ABSTRACT FROM AUTHOR]