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Excessive levels of higher alcohols have negative impacts on the quality of Baijiu. Understanding the key microorganisms responsible for producing higher alcohols and their assembly processes is crucial for controlling higher alcohols in multi-species Baijiu fermentation. This study investigated the changes in volatile compounds, including higher alcohols, and microbial communities in the four fermentation cycles of Jiang -flavor Baijiu. Higher alcohols were the most abundant in the first cycle. Through metatranscriptomic and culture-dependent analysis, Saccharomyces cerevisiae and four non- Saccharomyces yeasts (Pichia kudriavzevii , Zygosaccharomyces bailii , Schizosaccharomyces pombe , and Torulaspora delbrueckii) were demonstrated to be the main contributors to higher alcohol (isobutanol, isoamylol, and 1-propanol) production, with S. cerevisiae producing the highest levels. A higher abundance of Saccharomyces resulted in the highest levels of higher alcohols in the first cycle. Moreover, our results revealed that yeast community was assembled from stochastic to deterministic processes with the increase of fermentation cycles, driven by lactic acid. These findings provide valuable insights into controlling higher alcohol production in Baijiu fermentation. • Isobutanol, isoamylol, and 1-propanol were the main higher alcohols with significant differences between cycles. • S. cerevisiae and four non- Saccharomyces yeasts were the contributors for higher alcohol production. • Higher level of higher alcohols in the first cycle is produced by high abundance of Saccharomyces. • Yeast community was assembled from stochastic to deterministic processes, driven by lactic acid. [ABSTRACT FROM AUTHOR]

Pit fermentation process has a significant impact on Baijiu production. However, the dynamics patterns and environmental driving mechanisms in Jiang -flavor Baijiu pit fermentation remain unclear. Here, we present a multi-omics study on 180 Jiang -flavor Baijiu fermentation samples across the pit fermentation process. We revealed and validated the dynamics and metabolic functions of the core species employing both culture-independent (i.e., metagenomics and metatranscriptomics) and culture-dependent tools. Our findings delineate the fermentation into three distinct stages, each characterized by a unique microbial community, functional profile, and accumulation of flavor compounds. In stage I, Bacillus subtilis , Pichia kudriavzevii , and Saccharomyces cerevisiae were the most abundant species, while Acetilactobacillus jinshanensis , S. cerevisiae , P. kudriavzevii , Schizosaccharomyces pombe , and Zygosaccharomyces bailii had the highest transcriptional activity. In stage II, A. jinshanensis emerged as the most abundant and metabolically active species in stage II, reaching a proportion of 45.69% ± 20.21%, and maintained a leading role in stage III with a proportion of 65.75% ± 6.56%, a period marked by minimal microbial diversity and significant accumulation of key flavor substances, notably esters and acids. In addition, A. jinshanensis was isolated and its core acid-producing microbial status confirmed based on culture-dependent tools. Structural equation modeling indicated that A. jinshanensis plays crucial roles in the heterogeneous succession of alcohol-producing microorganisms, with spatial differences in acidity being a key factor. This work not only provides a robust analytical framework for understanding the Baijiu fermentation microbiome but also lays the groundwork for technological innovation in the fermentation industry. [Display omitted] • Revealing the microbiome dynamics during pit fermentation of Jiang -flavor Baijiu. • Clarifying the different functional stages of pit fermentation of Jiang -flavor Baijiu. • Revealing the differences in microbial structure and function at different stages. • Analyzing driving factors in heterogeneous succession of yeasts and lactic acid bacteria. [ABSTRACT FROM AUTHOR]

To detect the Epstein-Barr virus (EBV) viral load of children after hematopoietic stem cell transplantation (HSCT) using chip digital PCR (cdPCR). The sensitivity of cdPCR was determined using EBV plasmids and the EBV B95-8 strain. The specificity of EBV cdPCR was evaluated using the EBV B95-8 strain and other herpesviruses (herpes simplex virus 1, herpes simplex virus 2, varicella zoster virus, human cytomegalovirus, human herpesvirus 6, and human herpesvirus 7). From May 2019 to September 2020, 64 serum samples of children following HSCT were collected. EBV infection and the viral load of serum samples were detected by cdPCR. The epidemiological characteristics of EBV infections were analyzed in HSCT patients. The limit of detection of EBV cdPCR was 110 copies/mL, and the limit of detection of EBV quantitative PCR was 327 copies/mL for the pUC57-BALF5 plasmid. The result of EBV cdPCR was up to 121 copies/mL in the EBV B95-8 strain, and both were more sensitive than that of quantitative PCR. Using cdPCR, the incidence of EBV infection was 18.75% in 64 children after HSCT. The minimum EBV viral load was 140 copies/mL, and the maximum viral load was 3,209 copies/mL using cdPCR. The average hospital stay of children with EBV infection (184 ± 91 days) was longer than that of children without EBV infection (125 ± 79 days), P = 0.026. EBV cdPCR had good sensitivity and specificity. The incidence of EBV infection was 18.75% in 64 children after HSCT from May 2019 to September 2020. EBV cdPCR could therefore be a novel method to detect EBV viral load in children after HSCT. [ABSTRACT FROM AUTHOR]

Medium-temperature Daqu acts as a fermentation starter for strong-flavor Baijiu. However, there is limited research available in terms of its quality attributes and formation mechanisms. In this study, the distinct characteristics of different quality medium-temperature Daqu were examined using the novel Qu-omics techniques. Multivariate statistical analyses indicated that the high-quality strong-flavor medium-temperature Daqu had increased acidity and enzyme activity, with the most significant variation observed in acidic protease activity. We revealed for the first time that mucorpepsin derived from Rhizomucor pusillus was the primary source of the acidic protease in high-quality Daqu using in-depth analysis. Volatile composition analysis revealed a positive correlation between nitrogenous and acidic substances with the predominant bacterial genera of Daqu , while a negative correlation was observed with the dominant fungal genera. The principal source of acidic compounds in Daqu was revealed to be lactic acid bacteria, and the inter-group differences in aromatic compounds were extremely significant (p < 0.001). The levels of phenylmethanol, phenylethanol, benzaldehyde, phenol, and 4-ethylguaiacol were significantly higher in high-quality Daqu compared to abnormal Daqu , while notably lower levels of phenylacetaldehyde, (±)-1-phenyl-2-propanol, phenylacetone, and other off-flavor substances were detected in high-quality Daqu than in abnormal Daqu (p < 0.05). [Display omitted] • The quality characteristics of medium-temperature Daqu were studied using Qu-omics. • The dominant microorganisms in different quality Daqu were analyzed. • The enzymes and proteins of keystone taxa between different quality Daqu were elucidated. • Acidic protease corresponding proteins and microorganisms were identified by 'peeling onion'. [ABSTRACT FROM AUTHOR]

Unravelling the relationships between microbial community stability and function under environmental stress is critical to understanding microbial ecology but remains understudied in fermentation ecosystems. In this study, the relationship between lactic acid and microbial community was revealed during Jiang-flavour Baijiu fermentation using high-throughput sequencing and nontargeted metabolomics. Lactic acid was reduced by mono- and co-inoculation of lactic acid-degrading strains, Pichia kudriavzevii and Zygosaccharomyces bailii. Furthermore, reduced lactic acid strengthened microbial community stability, mainly characterized by higher network modularity and more positive interactions of species. Lactic acid had a significantly negative relation with network modularity (P = 0.03, Pearson's r = − 0.97). Moreover, the increase in network stability contributed to stronger community function, as indicated by the increase in ethanol, total esters, and total alcohols. Finally, metabolic function analysis showed that amino acid metabolism, starch and sucrose metabolism, pyruvate metabolism, the TCA cycle, nucleotide sugar metabolism, pyrimidine metabolism, and purine metabolism were the main pathways resulting in changes in microbial community stability and function. This study indicated that microbial community stability and function can be enhanced by the regulation of environmental factors and provided a possible strategy for the steady-state regulation of the microbial community in Baijiu fermentation. • Inoculation with P. kudriavzevii and Z. bailii reduced lactic acid during Baijiu fermentation. • Reduced lactic acid increased microbial community stability. • Microbial community stability was strongly linked to community function. • Possible metabolic mechanism related to the change of microbial community stability and function was illustrated. [ABSTRACT FROM AUTHOR]

To evaluate the safety and effectiveness of a vaccine based on latent membrane protein 2 (LMP2) modified dendritic cells (DCs) that boosts specific responses of cytotoxic T lymphocytes (CTLs) to LMP2 before and after intradermal injection in patents with nasopharyngeal carcinoma (NPC). DCs were derived from peripheral blood monocytes of patents with NPC. We prepared LMP2-DCs infected by recombinant adenovirus vector expressing LMP2 (rAd-LMP2). NPC patents were immunized with 2 x 10 LMP2-DCs by intradermal injection at week 0 and after the second and fourth weeks. Specific responses to LMP2 were detected by enzyme-linked immunospot (ELISPOT) assay at week 0 and at the fifth and eighth weeks. Local clinicians performed the follow-up and tracking of patients. We demonstrated that DCs derived from monocytes displayed typical DC morphologies; the expression of LMP2 in the LMP2-DCs vaccine was confirmed by immunocytochemical assay. Twenty-nine patients with NPC were enrolled in this clinical trial. The LMP2-DCs vaccine was well tolerated in all of the patients. Boosted responses to LMP2 peptide sub-pools were observed in 18 of the 29 patients with NPC. The follow-up data of 29 immunized patients from April, 2010 to April 2015 indicated a five-year survival rate of 94.4% in responders and 45.5% in non-responders. In this pilot study, we demonstrated that the LMP2-DCs vaccine is safe and effective in patients with NPC. Specific CTLs responses to LMP2 play a certain role in controlling and preventing the recurrence and metastasis of NPC, which warrants further clinical testing. [ABSTRACT FROM AUTHOR]

In social networks, the spread of influence has been studied extensively, but most efforts in existing literature are made on the product used by a single person. This paper attempts to address the product which is used by many persons such as the online game. When multiple people participate in one game, interaction between users is accompanied by browsing and clicking on advertisements, and operators can also earn certain advertising revenues. All these revenues are related to information interaction between people involved in one game. We use game profit to represent all of the revenues gained from players involved in one game and model the game profit maximization problem in social networks, which finds a seed set to maximize the game profit between players who are influenced to buy the game. We prove that the problem is NP-hard and the objective function is neither submodular nor supermodular. To solve it, we decompose it into the Difference between two Submodular functions (DS decomposition) and propose four heuristic algorithms. To address the complexity of computing objective function, we design a new sampling method based on reverse reachable set technology. Experiment results on real datasets show that our approaches perform well. [ABSTRACT FROM AUTHOR]

To further investigate the aerodynamic characteristics and control mechanisms of co-flow jet wings, this study presents the design of a co-flow jet wing (CFJ-CLARKY18) with an embedded micro centrifugal compressor. The CFJ-CLARKY18 wing, based on the CLARKY18 airfoil, incorporates a miniature centrifugal compressor positioned horizontally within the wing's cavity, with its rotor axis perpendicular to the wing chord line, thus alleviating geometric constraints and the compressor's exhaust swirl. The integration of the co-flow jet device with the wing is achieved through a split-flow channel design to ensure uniform co-flow jet injection, followed by verification of jet uniformity and calibration of six jet momentum coefficients. Subsequently, static and dynamic control experiments of the co-flow jet wing are conducted in an open-return wind tunnel, utilizing force measurement systems and high-speed particle image velocimetry tools to investigate its aerodynamic characteristics and control mechanisms. Static stall tests indicate that, compared to the original wing, the CFJ-CLARKY18 wing exhibits a significant increase in lift and a noticeable delay in stall angle. At low angles of attack, an increase in co-flow jet momentum leads to a reduction in drag coefficient, with the possibility of achieving negative drag (thrust) even at high co-flow jet momentum coefficients. The results of dynamic stall tests with force measurements indicate that, while keeping the reduced frequency constant, an increase in co-flow jet momentum coefficient results in higher maximum lift and average lift coefficients, accompanied by a significant reduction in average drag coefficient and the hysteresis loop area of the lift coefficient. Despite the increased reduced frequency exacerbating the wing's stall effect, the stall effect weakens significantly once the co-flow jet momentum coefficient is increased. [ABSTRACT FROM AUTHOR]

Abstract Many traditional fermented foods and beverages in both eastern and western countries are produced with the addition of starter cultures. Daqu is the undefined starter used for Chinese liquor, which contributed many fermentation functional fungal and bacterial communities to liquor fermentation process. However, the sources of these microbial communities and how these microorganisms formed in Daqu are still unclear. In this study, high-throughput sequencing combined with microbial source tracking analysis were applied to analyze the sources of the microbial communities in Daqu. We found fungal communities in Daqu were mainly originated from Daqu making environments (mainly tools and indoor ground), including Saccharomycopsis fibuligera , Pichia kudriavzevii , Rhizopus oryzae , Sterigmatomyces elviae , Aspergillus flavus/oryzae , Hyphopichia burtonii and Lichtheimia corymbifera. Meanwhile, most of bacterial communities in Daqu were from raw materials, including Gammaproteobacteria, Alphaproteobacteria and Bacilli. During Daqu-making process, the abundance of Gammaproteobacteria and Alphaproteobacteria that were not beneficial to liquor fermentation declined, but the abundance of the fermentation functional yeasts and Bacilli increased. Moreover, network analysis showed the bacteria in Daqu might be the drivers for the microbial succession during the Daqu-making process. This study shows that the Daqu production technology is a good way to screen fermentation functional microorganisms from complex environmental microbial communities. Highlights • Raw materials were the main sources of bacteria in Daqu. • Daqu-making environment was the main source of fungi in Daqu. • Bacteria drove the microbial succession during Daqu-making process. [ABSTRACT FROM AUTHOR]

Abstract The interaction and the coupling between the plasma filaments introduce some ultrafast phenomena, which not only reveal deep physical mechanisms, but also provide clues to develop the plasma filament-based applications. In this paper, the terahertz (THz) radiation from two plasma filaments with opposite directions, which are produced by focusing two counter propagating femtosecond laser pulses with a pair of off-axis-parabolic mirrors, is measured using electro-optic sampling detection method. The experimental results show that the pre-plasma weakens the THz radiation in the cases of with and without an external biased field. The lifetime of the plasma filament is estimated using the time evolution of the THz peaks. It is found that the THz radiation keeps weaker even when one pump pulse is 300 ps before the other one, which indicates that the lifetime of the plasma filament is longer than 300 ps. In addition, the THz pulses have similar shapes at different time delays between two pump laser pulses. Its underlying physical mechanisms are discussed as well. Highlights • Two plasma filaments with opposite directions are produced by two counter propagation laser beams. • The terahertz radiation from such configuration is measured with electro-optic sampling method. • The results show that the pre-plasma decreases the terahertz generation. • Such ultrafast phenomenon is used to estimate the lifetime of the filament plasma. [ABSTRACT FROM AUTHOR]

Loss of transcription-coupled histone H3 lysine 36 trimethylation (H3K36me3) contributes to shorter lifespans in eukaryotes. However, the molecular mechanism of the decline of H3K36me3 during aging remains poorly understood. Here, we report that the degradation of the methyltransferase Set2 is the cause of decreased H3K36me3 levels during chronological aging in budding yeast. We show that Set2 protein degradation during cellular senescence and chronological aging is mainly mediated by the ubiquitin-conjugating E2 enzyme Ubc3 and the E3 ligase Bre1. Lack of Bre1 or abolishment of the ubiquitination stabilizes Set2 protein, sustains H3K36me3 levels at the aging-related gene loci, and upregulates their gene expression, thus leading to extended chronological lifespan. We further illustrate that Gcn5-mediated Set2 acetylation is a prerequisite for Bre1-catalyzed Set2 polyubiquitination and proteolysis during aging. We propose that two sequential post-translational modifications regulate Set2 homeostasis, suggesting a potential strategy to target the Gcn5-Bre1-Set2 axis for intervention of longevity. [Display omitted] • Decreased H3K36me3 levels are associated with chronological aging • Ubc3- and Bre1-mediated polyubiquitination and degradation of Set2 expedite aging • Gcn5 acetylates Set2 to provoke its degradation during aging • High H3K36me3-mediated expression of aging-related gene extends yeast lifespan Li et al. demonstrate the importance of H3K36me3 levels in yeast chronological lifespan. They define a molecular mechanism wherein Gcn5-mediated acetylation, followed by Bre1-/Ubc3-mediated polyubiquitination, results in Set2 degradation. This process ultimately reduces H3K36me3 levels and silences aging-related genes, thereby contributing to chronological aging. [ABSTRACT FROM AUTHOR]

Despite the observation of regionally distinct flavor characteristics of Chinese Strong-flavor Baijiu (CSFB) in recent decades, we still lack a comprehensive understanding of how such geography-dependent flavors establish. Here, 168 samples from 8 distilleries were collected across the main production regions of CSFB, and the factors driving the establishment of regional characteristics were investigated by amplicon and metatranscriptome sequencing combined with measurements of climate environments. We demonstrated that microbial communities in both fermented grains and surrounding environments (air and ground) exhibit regional patterns. More importantly, we found the regional patterns of microbial communities at the functional level by contributional diversity analysis. Such microbial and functional patterns correlated with the volatile metabolites profiles of finished fermented grains and predicted the abundance of metabolites in finished fermented grains. Furthermore, we found that climate factors, particularly mean relative humidity, affected fungal rather than bacterial diversity in fermented grains and environments (air and ground), thereby contributing to CSFB regional distinctiveness. Our study provided a basic landscape of the regional patterns of microbiota and metabolites across the main CSFB-producing regions and the dominating shaping factors. [Display omitted] • The microbial biogeography of FGs and environments was studied at provincial scale. • Significant differences in microbial structure and functions among regions found. • High functional redundancy of microbiota in Sichuan region found. • Microbial regional patterns predicted volatile metabolite abundance. • Fungal communities in air and ground contribute to CSFB regional flavor formation. [ABSTRACT FROM AUTHOR]

The compound p -cresol is the major off-odor and toxic component of strong aroma-type Chinese liquor. To trace its origin, the p- cresol contents in the liquor-making process were detected by gas chromatography-mass spectrometry. The prokaryotic communities involved in the process were revealed by 16S rRNA gene MiSeq sequencing. The results showed that the microbial diversity and concentration of p -cresol in pit mud significantly increased with increased pit depth. Canonical correspondence analysis further revealed that p -cresol was positively correlated with the genera Aminobacterium , Clostridium , Sedimentibacter and Syntrophomonas . On investigating potential p- cresol producers, we obtained 11 species from pit mud samples using selective culture media. Clostridium butyricum , Clostridium tyrobutyricum , Clostridium aminovalericum and Eubacterium contortum were confirmed to possess the capacity for p -cresol production. Moreover, based on volatile compounds data, these strains were assigned to the same clusters characterized by the high abundance of butanoic acid and p -cresol. Furthermore, 24 pairs of significant correlations were identified from 14 genera using co-occurrence network analysis. Clostridium was the hub in pit mud and could be inhibited by increasing levels of Lactobacillus. These findings represented a step forward for controlling p -cresol in a complex microbial community of Chinese liquor. [ABSTRACT FROM AUTHOR]

Research on changes in the fluid edge of a wave flume is important for experimental hydrodynamics. However, disturbances often occur because of the presence of sensors. To solve this problem, a new grey-scale image processing method for fluid edge analysis is presented here. By fusing methods combining image gradients and image segmentation with shifting-window technology and with concepts derived from experimental fluid mechanics, the proposed method can overcome many of the inherent challenges of fluid-edge measurement. First, the geodesic distance is modified to obtain a class curve. Second, an edge position is determined by the inflection point of the class curve related to the gradient peak distribution. Next, the position of the interrogation window is relocated with reference to neighbors or to previous results, and the current edge position can be calculated according to the predicted value. During the computation, the interrogation window can change its position adaptively with fluid motion, ensuring that the amount of data to be analyzed always remains stable. A model combining the class curve and gradient curve can improve the validity of edge identification. Finally, the performance of the proposed method has been evaluated using images in a glass flume. The results show that the proposed method for studying the fluid edge is effective and robust. [ABSTRACT FROM AUTHOR]

The fermentation process of Chinese strong-flavor liquor involves numerous microbes originating from Daqu and pit mud. Daqu is the starter of fermentation, and pit mud acts as another source of inoculum of microbes in the liquor-making process. However, the contribution of microbes in pit mud and Daqu to fermented grain, and the sources of microbes in fermented grain are still waiting to be defined clearly. In this study, prokaryotic communities in fermented grain, pit mud and Daqu were identified via next generation sequencing of the V4 region of 16S rRNA gene. Principal-coordinate analysis indicated that Daqu had stronger influence on the prokaryotic communities in fermented grain at the prophase of fermentation, but pit mud influenced the fermented grain continuously during the whole fermentation process. Totally, 299 genera were detected in all fermented grain, pit mud and Daqu samples. Among them, 204 genera were detected in 3 days' fermented grain. Ten genera ( Lactobacillus , Leuconostoc , Staphylococcus , Gluconobacter , Acetobacter , Petrimonas , Clostridium , Ruminococcus , Methanobacterium and Methanobrevibacter ) were dominant, and accounted for 84.31%–87.13% relative abundance of the total prokaryotic community in fermented grain. Venn analysis indicated Daqu was the main source of strict aerobes and facultative aerobes, which took up over 74% of prokaryotic communities in fermented grain. Conversely, pit mud was the sustained-release source of anaerobes, which accounted for over 14% of prokaryotic communities in fermented grain. In addition, part of anaerobes originated from both Daqu and pit mud. This study could help track the source of prokaryotic communities in fermented grain, and improve the quality and controllability in liquor production. [ABSTRACT FROM AUTHOR]

Viruses are highly abundant in nature, associated with quality and safety of traditional fermented foods. However, the overall viral diversity and function are still poorly understood in food microbiome. Traditional baijiu fermentation is an ideal model system to examine the diversity and function of viruses owing to easy access, stable operation, and domesticated microbial community. Equipped with cutting-edge viral metagenomics, we investigated the viral community in the fermented grain and fermentation environment, as well as their contribution to baijiu fermentation. Viral communities in the fermented grains and fermentation environment are highly similar. The dominant viruses were bacteriophages, mainly including the order Caudovirales and the family Inoviridae. Furtherly, association network analysis showed that viruses and bacteria were significantly negatively correlated (P < 0.01). Viral diversity could significantly influence bacterial and fungal succession (P < 0.05). Moreover, we proved that starter phages could significantly inhibit the growth of Bacillus licheniformis in the logarithmic growth stage (P < 0.05) under culture condition. Based on the functional annotations, viruses and bacteria both showed high distribution of genes related to amino acid and carbohydrate metabolism. In addition, abundant auxiliary carbohydrate-active enzyme (CAZyme) genes were also identified in viruses, indicating that viruses were involved in the decomposition of complex polysaccharides during fermentation. Our results revealed that viruses could crucially affect microbial community and metabolism during traditional fermentation. • Bacteriophages were predominant viruses in the sauce-flavor baijiu fermentation. • Viral diversity influences the microbial community and succession. • Auxiliary metabolic genes carried by viruses may affect the saccharification and amino acid metabolism of the host. [ABSTRACT FROM AUTHOR]