Gene co-option, duplication and divergence of cement proteins underpin the evolution of bioadhesives across barnacle life histories.

Acquisition of new genes often results in the emergence of novel functions and is a key step in lineage-specific adaptation. As a group of sessile crustaceans, barnacles establish permanent attachment through initial cement secretion at the larval phase followed by continuous cement secretion in juveniles and adults. However, the origins and evolution of barnacle larval and adult cement proteins remain poorly understood. By performing microdissection of larval cement glands, transcriptome and shotgun proteomics and immunohistochemistry validation, we identified 30 larval and 27 adult cement proteins of the epibiotic turtle barnacle Chelonibia testudinaria, of which the majority are stage- and barnacle-specific. While only two proteins, SIPC and CP100K, were expressed in both larvae and adults, detection of protease inhibitors and the cross-linking enzyme lysyl oxidase paralogs in larvae and adult cement. Other barnacle-specific cement proteins such as CP100k and CP52k likely share a common origin dating back at least to the divergence of Rhizocephala and Thoracica. Different CP52k paralogues could be detected in larval and adult cement, suggesting stage-specific cement proteins may arise from duplication followed by changes in expression timing of the duplicates. Interestingly, the biochemical properties of larval- and adult-specific CP52k paralogues exhibited remarkable differences. We conclude that barnacle larval and adult cement systems evolved independently, and both emerged from co-option of existing genes and de novo formation, duplication and functional divergence of lineage-specific cement protein genes. Our findings provide important insights into the evolutionary mechanisms of bioadhesives in sessile marine invertebrates.

An All-Natural Wood-Inspired Aerogel.

The oriented pore structure of wood endows it with a variety of outstanding properties, among which the low thermal conductivity has attracted researchers to develop wood-like aerogels as excellent thermal insulation materials. However, the increasing demands of environmental protection have put forward new and strict requirements for the sustainability of aerogels. Here, we report an all-natural wood-inspired aerogel consisting of all-natural ingredients and develop a method to activate the surface-inert wood particles to construct the aerogel. The obtained wood-inspired aerogel has channel structure similar to that of natural wood, endowing it with superior thermal insulation properties to most existing commercial sponges. In addition, remarkable fire retardancy and complete biodegradability are integrated. With the above outstanding performances, this sustainable wood-inspired aerogel will be an ideal substitute for the existing commercial thermal insulation materials.

VDAC1 promotes cardiomyocyte autophagy in anoxia/reoxygenation injury via the PINK1/Parkin pathway.

Ischemia/reperfusion (I/R) is a well-known injury to the myocardium, but the mechanism involved remains elusive. In addition to the well-accepted apoptosis theory, autophagy was recently found to be involved in the process, exerting a dual role as protection in ischemia and detriment in reperfusion. Activation of autophagy is mediated by mitochondrial permeability transition pore (MPTP) opening during reperfusion. In our previous study, we showed that MPTP opening is regulated by VDAC1, a channel protein located in the outer membrane of mitochondria. Thus, upregulation of VDAC1 expression is a possible trigger to cardiomyocyte autophagy via an unclear pathway. Here, we established an anoxia/reoxygenation (A/R) model in vitro to simulate the I/R process in vivo. At the end of A/R treatment, VDAC1, Beclin 1, and LC3-II/I were upregulated, and autophagic vacuoles were increased in cardiomyocytes, which showed a connection of VDAC1 and autophagy development. These variations also led to ROS burst, mitochondrial dysfunction, and aggravated apoptosis. Knockdown of VDAC1 by RNAi could alleviate the above-mentioned cellular damages. Additionally, the expression of PINK1 and Parkin was enhanced after A/R injury. Furthermore, Parkin was recruited to mitochondria from the cytosol, which suggested that the PINK1/Parkin autophagic pathway was activated during A/R. Nevertheless, the PINK1/Parkin pathway was effectively inhibited when VDAC1 was knocked-down. Taken together, the A/R-induced cardiomyocyte injury was mediated by VDAC1 upregulation, which led to cell autophagy via the PINK1/Parkin pathway, and finally aggravated apoptosis.

Factors for postoperative recurrence of orbital solitary fibrous tumor: an analysis of long-term clinical follow-up results from a Chinese tertiary hospital.

BACKGROUND: This study analyzed the clinical features, imaging manifestations, histopathology, immunohistochemistry, and surgical approaches of the orbital solitary fibrous tumor (OSFT), as well as the factors for postoperative recurrence of such disease. METHODS: The clinical data of 16 patients with OSFT treated in our center from 2003 to 2020 were analyzed retrospectively, and the clinical symptoms, treatment methods, and follow-up results were recorded. RESULTS: Of the 16 patients, 8 were females (50.0 %) and 8 were males (50.0 %); the average age of treatment was 37 ± 7 years and the median follow-up time was 74 (8, 228) months. Sixteen patients with OSFT underwent a total of 29 operations, of which 12 were transorbital approach operations and 17 were transfronto-orbital approach operations. Ten patients (10/16, 62.5 %) had recurrence. The recurrence rate of transorbital approach operations was 83.3 % (10/12), and the recurrence rate of transfronto-orbital approach operations was 17.6 % (3/17). No patients had treatment-related complications. CONCLUSIONS: The main pathological feature of OSFT is a benign tumor. OSFT has a tendency to grow toward the cranio-orbital junction. The postoperative recurrence rate of OSFT is relatively high, so complete tumor resection is very important for prognosis. Inappropriate surgical approaches can lead to incomplete removal of the tumor and cause recurrence. Choosing the correct operation approach according to the position of the OSFT in the orbit and complete removal of the dura mater and bone affected by the tumor is crucial for the prognosis. Nevertheless, regular long-term follow-up after complete resection is necessary.

Radiation tolerance of La-doped nanocrystalline steel under heavy-ion irradiation at different temperatures.

Nanostructured materials have great potential for use as structural materials in advanced nuclear reactors due to the high density of grain boundaries that can serve as sinks to absorb irradiation-induced defects. In the present study, the irradiation tolerance of a La-doped nanocrystalline 304 austenitic stainless steel (NC-La) with a grain size of about 40 nm was investigated under an irradiation of 6 MeV Au ions to 1.5 × 1016 ions cm-2 at 600 °C and room temperature. Compared to its coarse-grained counterpart, in La-doped nanocrystalline steel no visible voids were observed at high-temperature irradiation, and no significant difference in extended defects, such as irradiation-induced dislocation loops or clusters, were found between irradiated and unirradiated areas at room temperature irradiation. Furthermore, the nano grain remains stable under irradiation, and no significant grain growth occurs at both irradiation temperatures. The excellent irradiation tolerance of the La-doped nanocrystalline alloys is attributed to the abundant grain boundaries and enhanced stability of nano grains induced by the Zener pinning effect and La segregation on grain boundaries. This study therefore demonstrates the superior irradiation tolerance of the La-doped nanocrystalline steel.

[Analysis of relevant factors affecting the visual prognosis of traumatic optic neuropathy].

OBJECTIVE: To investigate the relevant factors affecting the prognosis of traumatic optic neuropathy (TON). METHODS: A total of 685 cases (719 eyes) of TON from June 2007 to June 2012 were analyzed retrospectively. A total of 9 independent variables (X) including sex, side of TON, duration of coma, vision after trauma, fracture of optic nerve canal, fracture of big ridge of sphenoid bone, hematoma in sphenoid sinus and surgical treatment, and the dependent variable (Y) of visual prognosis were analyzed using the unconditioned Logistic regression analysis to find the risk factors for the visual prognosis of TON. RESULTS: A total of 325 eyes (45.2%) recovered out of 719 eyes. Four variables showed a significant relation with the visual recovery: duration of coma>0.5 h (X3, P<0.01), remnant vision after trauma (X4, P<0.01) and sphenoid ridge fractures (X7, P<0.01), and surgical treatment (X9, P<0.01). These factors above were also proved to be significant in Logistic regression. CONCLUSION: The duration of coma>0.5 h, no light perception after trauma, sphenoid ridge fractures are risk factors of visual recovery, while surgical treatment is the protective factor for the visual recovery after TON.

[Transnasal endoscopic management of foreign body injuries at orbital-skull base].

OBJECTIVE: To explore the feasibility and methods of transnasal endoscope for removing foreign bodies at orbital-skull base. METHODS: Retrospective analyses were performed for 8 cases of foreign body injuries at orbital-skull base at our department from January 2009 to January 2014. The foreign bodies were metallic (n = 4) and wooden (n = 4). Six cases were only within orbit while the remainder had nasal-orbital foreign bodies. The symptoms included preoperative visual loss (n = 6), visual deterioration (n = 2) and eye movement disorder (n = 5). All underwent transnasal endoscopic removal. RESULTS: Foreign bodies were totally removed. During a follow-up period of 3 months to 4 years, there was no recovery of preoperative visual loss (n = 6). Two patients with reduced vision recovered to normal after 3 months. Eye movement disorder fully recovered in 4 cases and 1 case of eye movement disorder had partial recovery. CONCLUSION: Endoscopic removal of foreign body at orbital-skull base has the advantage of mini-invasiveness and non-facial surgical scar.

Insight into the multi-scale structure and retrogradation of corn starch by partial gelatinization synergizing with epicatechin/epigallocatechin gallate.

Starch retrogradation is of great importance to the quality of starch-based food. This study investigated the effect of partial gelatinization (PG) synergizing with polyphenol (epicatechin, EC; epigallocatechin gallate, EGCG) on the multi-scale structure and short/long-term retrogradation of corn starch (CS). The PG synergizing with EC/EGCG substantially suppressed the short/long-term retrogradation properties of CS. These could be confirmed by the decreased storage modulus and viscosity, the relative crystallinity (1.54%, 3.56%), and the retrogradation degree (9.99%, 20.18%) of CS during storage for 1, 14 days after PG synergizing with EGCG and EC, respectively. This is because PG treatment promoted the hydrogen bond interaction between disordered starch molecules and EC/EGCG. These were proven by the larger aggregation, more and brighter fluorescents, and the reduced long/short-range order structures in CS after PG synergizing with EC/EGCG. This study is helpful for the development of foods with enhanced nutrition and low-retrogradation.

Identifying competing endogenous RNA regulatory networks and hub genes in alcoholic liver disease for early diagnosis and potential therapeutic target insights.

Alcoholic liver disease (ALD) has a complex pathogenesis. Although early-stage ALD can be reversed by ceasing alcohol consumption, early symptoms are difficult to detect, and several factors contribute to making alcohol difficult to quit. Continued alcohol abuse worsens the condition, meaning it may gradually progress into alcoholic hepatitis and cirrhosis, ultimately, resulting in irreversible consequences. Therefore, effective treatments are urgently needed for early-stage ALD. Current research mainly focuses on preventing the progression of alcoholic fatty liver to alcoholic hepatitis and cirrhosis. However, challenges remain in identifying key therapeutic targets and understanding the molecular mechanisms that underlie the treatment of alcoholic hepatitis and cirrhosis, such as the limited discovery of effective therapeutic targets and treatments. Here, we downloaded ALD microarray data from Gene Expression Omnibus and used bioinformatics to compare and identify the hub genes involved in the progression of alcoholic fatty liver to alcoholic hepatitis and cirrhosis. We also predicted target miRNAs and long non-coding RNAs (lncRNAs) to elucidate the regulatory mechanisms (the mRNA-miRNA-lncRNA axis) underlying this progression, thereby building a competitive endogenous RNA (ceRNA) mechanism for lncRNA, miRNA, and mRNA. This study provides a theoretical basis for the early treatment of alcoholic hepatitis and cirrhosis and identifies potential therapeutic targets.

Boosting the Antioxidant Potential of Polymeric Proanthocyanidins in Litchi (Litchi chinensis Sonn.) Pericarp via Biotransformation of Utilizing Lactobacillus Plantarum.

In order to enhance the efficient utilization of polymeric proanthocyanidins from litchi pericarp, a process for transforming litchis' polymeric proanthocyanidins (LPPCs) by using Lactobacilli has been established for products with highly antioxidative properties. Lactobacillus plantarum was selected to enhance the transformation effect. The transformation rate of LPPCs reached 78.36%. The content of litchis' oligomeric proanthocyanidins (LOPCs) in the products achieved 302.84 µg grape seed proanthocyanidins (GPS)/mg DW, while that of total phenols was 1077.93 gallic acid equivalents (GAE) µg/mg DW. Seven kinds of substances have been identified in the products by using the HPLC-QTOF-MS/MS method, among which 4-hydroxycinnamic acid, 3,4-dihydroxy-cinnamic acid, and proanthocyanidin A2 were major components. The in vitro antioxidative activity of the products after transformation was significantly (p < 0.05) higher than those of LOPCs and LPPCs. The scavenging activity of the transformed products for DPPH free radicals was 1.71 times that of LOPCs. The rate of inhibiting conjugated diene hydroperoxides (CD-POV) was 2.0 times that of LPPCs. The scavenging activity of the products for ABTS free radicals was 11.5 times that of LPPCs. The ORAC value of the products was 4.13 times that of LPPCs. In general, this study realizes the transformation of polymeric proanthocyanidins into high-activity small-molecule substances.

Evaluation of Dynamic Changes and Regularity of Volatile Flavor Compounds for Different Green Plum (Prunus mume Sieb. et Zucc) Varieties during the Ripening Process by HS-GC-IMS with PLS-DA.

Headspace gas chromatography-ion mobility spectrometry and partial-least-squares discriminant analysis (PLS-DA) were adopted to analyze the rule of change in flavor substances for different varieties of green plums at different levels of maturity (S1-immature, S2-commercially mature, and S3-fully mature). The results showed that 68 kinds of volatile flavor substances were identified in all green plum samples. The types and contents of such volatile substances experienced a V-shaped trend with an increasing degree of green plum maturity. During the S1 and S2 stages, aldehydes, ketones, and a small amount of alcohols were the main volatile flavor substances in the green plum samples. During the S3 stage, esters and alcohols were the most important volatile flavor components in the green plum pulp samples, followed by terpenes and ketones. YS had the most types and highest contents of volatile flavor substances in three stages, followed by GC and DZ. By using the PLS-DA method, this study revealed the differences in flavor of the different varieties of green plums at different maturity stages, and it identified eight common characteristic volatile flavor substances, such as ethyl acetate, 3-methylbutan-1-ol, and 2-propanone, produced by the different green plum samples during the ripening process, as well as the characteristic flavor substances of green plums at each maturity stage (S1-S3).

Cellulose nanofiber from pomelo spongy tissue as a novel particle stabilizer for Pickering emulsion.

For the high-value utilization of agricultural wastes to promote sustainable development, in this work, pomelo spongy tissue cellulose nanofibers (PCNFs) with lengths >3 µm and widths 33-64 nm were prepared by high pressure homogenization (HPH). The PCNFs were used to stabilized Pickering emulsion, and the emulsion with oil phase fraction in the range of 10 % to 50 % (w/w) exhibited outstanding stability. The increase in PCNFs concentration also enhanced the three-dimensional network structure, resulting in higher stability of the emulsion. Moreover, the droplet size distribution of emulsion would be greatly improved by moderate heating. No creaming was observed in emulsions over a wide range of ionic strengths (20-200 mM) after storage for 30 d. And the excellent emulsifying properties of the PCNFs were mainly attributed to their adsorption at the oil-water interface and the formation of a three-dimensional network structure. All the results indicated that the PCNF would be a promising novel stabilizer for Pickering emulsions.

Ultrastrong, Thermally Stable, and Food-Safe Seaweed-Based Structural Material for Tableware.

Widely used disposable plastic tableware is usually buried or directly discharged into the natural environment after using, which poses potential threats to the natural environment and human health. To solve this problem, nondegradable plastic tableware needs to be replaced by tableware composed of biodegradable structural materials with both food safety and the excellent mechanical and thermal properties. Here, a food-safe sargassum cellulose nanofiber (SCNF) is extracted from common seaweed in an efficient and low energy consuming way under mild reaction conditions. Then, by assembling the SCNF into a dense bulk material, a strong sargassum cellulose nanofiber structural material (SCNSM) with high strength (283 MPa) and high thermal stability (>160 °C) can be prepared. The SCNSM also possesses good machinability, which can be processed into tableware with different shapes, e.g., knives and forks. The overall performance of the SCNSM-based tableware is better than commercial plastic, wood-based, and poly(lactic acid) tableware, which shows great application potential in the tableware field.

Influence of the Injection Scheme on the Enhanced Oil Recovery Ability of Heterogeneous Phase Combination Flooding in Mature Waterflooded Reservoirs.

With the maturity of waterflooded reservoirs, owing to serious heterogeneity, the fluid will channel through the thief zone, leading to considerable remaining oil unrecovered in the upswept area. To further enhance oil recovery (EOR) after waterflooding, the heterogeneous phase combination flooding (HPCF) was composed of a polymer, branched-preformed particle gel (B-PPG), and surfactant. For the sake of improving the economic efficiency, the influence of the injection scheme on the EOR of HPCF with an equal chemical agent cost was investigated by sand-pack flooding experiments. Then, visual plate sand-pack model flooding experiments were performed to study the swept area of HPCF under different injection schemes. Results demonstrated that the total EOR of HPCF under different injection schemes ranged from 33.5 to 39.3%. Moreover, the EOR of HPCF under the alternation injection (AI) scheme was the highest, followed by the concentration step change injection (CI) scheme, and that of the simultaneous injection (SI) scheme was the least. The visual flooding experimental results showed that the swept area of HPCF after waterflooding under the AI scheme was higher than that of the SI. Moreover, in view of qualitative analysis of remaining oil distribution, the EOR of AI of HPCF was higher than that of SI, which was consistent with the parallel sand-pack flooding results.

The Significance of The Detection of Serum Lactate Dehydrogenase, Hypersensitive C-Reactive Protein, and N-Terminal Pro-Brain Natriuretic Peptide for the Evaluation of the Severity and Progression of Pediatric Patients with Traumatic Brain Injury.

OBJECTIVE: This study aimed to investigate changes in the levels of serum lactate dehydrogenase (LDH), hypersensitive C-reactive protein (hs-CRP), and N-terminal pro-brain natriuretic peptide (NT-proBNP) in pediatric patients with traumatic brain injury and the clinical significance of detecting these changes for the evaluation of injury severity and patient progress. METHODS: A retrospective study was conducted on 40 pediatric patients admitted to the Tongren Hospital of China Capital Medical University with traumatic brain injury between January 2018 and December 2019. Immunoturbidimetric assay and electrochemiluminescence were used to detect the serum levels of LDH, hs-CRP, and NT-proBNP. Correlation analysis was used to determine the degree of association between the indicators and the sensitivity and specificity of each indicator. RESULTS: The serum levels of LDH, hs-CRP, and NT-proBNP in the poor-prognosis group were higher than those in the good-prognosis group, and the differences were statistically significant (P < 0.05). CONCLUSION: The detection of serum LDH, hs-CRP, and NT-proBNP might be of great significance for the evaluation of the severity of a traumatic brain injury, disease progression, and the prognosis of pediatric patients with traumatic brain injury. The combined detection of the relevant indicators could provide more effective sensitivity and specificity and therefore offer better guidance and assistance in clinical practice.

Physicochemical, structural and functional properties of pomelo spongy tissue pectin modified by different green physical methods: A comparison.

Pectin is a valuable bioactive ingredient, but its practical application is limited in many areas due to its high molecular weight and complex structure. In this work, the effect of different physical methods (ultra-high pressure, ultrasonic, and high-temperature cooking) on the physicochemical, structural, and functional characteristics of pomelo spongy tissue pectin (PP) were investigated. Ultra-high pressure treatment (300 MPa, 15 min) decreased the degree of esterification (DE, 4.53 %) and the degree of acetylation (DA, 2.76 %) of PP. And the PP subjected to the ultrasonic treatment (200 W, 20 min) exhibited the highest esterification degree (66.02 %), galacturonic acid content (GalA, 406.40 mg/g), and degradation enthalpy (66.93 J/g). Meanwhile, the PP treated with high-temperature cooking (HCT, 120 °C, 30 min) had the lowest acetylation degree (2.02 %), molecular weight (8.48 × 104 Da), and GalA content (254.92 mg/g). SEM and XRD results showed that the degradation effect of high temperatures on PP was more evident than other physical modification methods. Remarkably, all modified pectin solutions showed lower viscosity compared to untreated PP solution. Among these PP samples, higher antioxidant activity (103.29-134.22 mmol TE/g FRAP and 646.27-705.25 mmol TE/g ORAC values) was found in the HCT-treated PP. Moreover, the ultra-high pressure and ultrasound modified pectins revealed better emulsifying activity and emulsifying stability than unmodified PP. The results of this study indicated that the PP could be treated to achieve the desired functional application through these three physical modification methods.

Morphological Pattern of Building Clusters in Cold Regions: Evidence from Harbin.

The rapidly changing global conditions of the environment and climate have resulted in higher requirements for urban design. Significant annual temperature variations and large day/night temperature differences in cold-region cities leads to high energy consumption. Therefore, it is challenging to achieve low energy consumption in cold-region cities. Urban morphology focuses on the physical elements of urban areas, reflecting the relationship between the city and its environment and the city's response to natural climatic conditions. Building clusters are common in cold regions due to the extreme climate. Thus, it is crucial to study the energy performance of cities by considering urban morphology. This study focuses on four morphological patterns of building clusters: point, linear, courtyard, and mixed patterns. A case study is conducted in Harbin, a cold-region city in China. Samples of the four morphological patterns are extracted, and GIS analysis and manual labeling are used to analyze the dominant morphological patterns of building clusters in cold regions. Average nearest-neighbor analysis is used to obtain quantitative results and determine the prevalence of different morphological patterns of building clusters in cold regions. This process can be used to determine the dominant patterns of urban building clusters and provide a scientific basis for selecting the morphological patterns of new building clusters in cold regions.

Yellow pigment from gardenia fruit: structural identification and evaluation of cytotoxic activity in HepG2 cells by induction of apoptosis.

The preparation process of yellow pigment (YP) from gardenia (Gardenia jasminoides) fruit was investigated, and the main components of YP were characterized by liquid chromatography-time of flight-mass spectrometer/mass spectrometer (LC-TOF-MS/MS). Furthermore, cytotoxic activity in HepG2 cells by induction of apoptosis was also evaluated. The preparation results indicated that the color value of YP was 498.34, which was 8.6 times higher than crude YP. Fifteen compounds in YP were identified, and crocins were the predominant compounds. The cell experiment results showed that YP inhibited the proliferation of HepG2 cells in a time- and dose-dependent manner. Moreover, YP also inhibited HepG2 cells in G2/M stage, increased the level of intracellular reactive oxygen species (ROS), and enhanced cell apoptosis. Real-time quantitative polymerase chain reaction (RT-PCR) analysis revealed the up-regulation of caspase-3, 8, 9, and bax and down-regulation of bcl-2 in HepG2 cells. Overall, these findings suggested that YP had potential cytotoxic activity in HepG2 cells by induction of apoptosis, which might be beneficial to human health. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01133-9.

The outcome of surgical and non-surgical treatments for traumatic optic neuropathy: a comparative study of 685 cases.

Background: The choice and efficacy of surgical or/and surgical treatments for traumatic optic neuropathy (TON) remained controversial by now. This study aims to present the outcomes of surgical and nonsurgical treatments for TON in our center. Methods: A total of 685 consecutive patients were retrospectively included in the study. And divided into surgical and non-surgical groups. All cases were treated with corticosteroids for 3 days after admission. Endoscopic optic decompression was applied to 479 patients of surgical group; The other 206 patients of nonsurgical were administered with corticosteroids alone. The visual outcomes before and after treatment were compared with Wilcoxon rank and tests. The improvement rate between two groups were compared with chi-square test. Results: The visual acuity (VA) after treatment was significantly better than that before treatment (P=0.000). Overall VA improvement rate in the surgical group was better than that in non-surgical group (42.8% vs. 35.4%) with no significant difference (P=0.072). The VA improvement rate was significant greater in the surgical group than that in the non-surgical group in the patients with NLP before treatment (P=0.028). The VA improvement rate was better in the surgical group than that in the non-surgical group (71.9% vs. 57.8%) but with no significant difference. The final overall VA was 0.1 or better in 43 cases; 104 cases were able to count fingers; hand motion (HM) became perceivable in 132 cases; light perception (LP) was achieved in 53 cases; and no light perception (NLP) remained in 353 cases. Conclusions: Endoscopic optic nerve decompression (EOND) combined with corticosteroids or corticosteroids alone could reach the improvement for patients with TON. The EOND combined with corticosteroids could achieve better VA improvement in patients with NLP.

GC-IMS and olfactometry analysis on the tea aroma of Yingde black teas harvested in different seasons.

This study aims to investigate the influence of different harvesting seasons on the aroma of black tea and the trend in the tea aroma variation. A total of 68 volatile substances was identified by gas chromatography coupled with ion-mobility spectrometry (GC-IMS), and 20 characteristic aroma-active compounds were quantitatively analyzed by gas chromatography-olfactometry coupled with aroma extract dilution analysis (GC-O AEDA) and odor activity value (OAV) analysis. These aroma-active compounds are mainly linalool, ß-damascenone, and benzeneacetaldehyde. Both methods confirmed that the aroma of tea changes with the harvesting seasons, showing a downward trend followed by an upward trend. Besides, black teas harvested in different seasons have their characteristic volatile compounds and metabolism precursors. The degradation of glycosides, carotenes, and amino acids are the most important degradation pathways for the formation of tea aroma. The PLSR results of GC-O-AEDA, OAV, and DSA data agree with each other, showing that five aroma attributes of the autumn tea have strong correlations. The autumn tea has the richest aroma, followed by the spring tea and the summer tea.