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•Succinct review on Chinese Baijiu Qu starters.•Flavor producing microbiota in Chinese Baijiu Qu starters.•The functional perspectives of microorganisms present in Chinese Baijiu Qu ...starters.•Correlation of microbiota in Qu starters and their functionality, especially flavor.
Chinese traditional fermented foods have a very long and complex history. These fermented foods have fascinating characteristics. These are mainly produced by autochthonous fermentation, involving an autochthonous complex microbiota in these fermented products which confers amazing functional characteristics. These include desirable taste, aroma, texture, exopolysaccharides, α-galactosidase, β-glucosidase, xylanase, antioxidants, and aglycone isoflavones which are produced along with other substances. Baijiu is a traditional Chinese spirit, which is widely consumed in East Asia, especially China, and is considered one of the most consumed spirits in the world. It is produced by autochthonously prepared traditional qu (starter culture), such as Xiaoqu, Daqu, Fuqu, and others. Microbial communities in various qu, thereof, have still not been properly characterized. There are several factors that contribute to microbial communities and to the final products of fermentation. This review shall succinctly describe recent scientific research on the production of flavor compounds by bacteria and fungi in Chinese traditional Baijiu qu (starter cultures), with special focus on the fungi and bacteria, and their functionalities with respect to flavor development in Baijiu.
•Canola yield is limited by source availability during seed filling while it can be limited by sink size established during flowering.•Agronomy management and breeding activities need to be directed ...toward increasing assimilate supply.
In canola, strong competition for assimilates from the overlapping of structural and reproductive growth can lead canola yield to be limited by source availability during seed filling. In this study, we tested this hypothesis by manipulating source-sink relationships in a series of experiments (i) shading during flowering and during seed filling, (ii) partial removal of flowers and pods of individual plants, (iii) defoliation at the vegetative stage and after full flowering, and (iv) supplemental irrigation during seed filling. Shading (60% of incoming radiation reduction) during flowering reduced the number of pods and seeds (sink) but increased mean seed weight (MSW), resulting in 24% yield loss. Shading during seed-filling reduced MSW as well as the number of pods and seeds per area and, causing 26% yield reduction compared to the control. Partial pod removal and full defoliation at full flowering decreased pods per plant and reduced yield by10–40%. Defoliation during the vegetative stage reduced yield by 11%. Supplemental irrigation increased yield by 10% without any impact on MSW. However, these manipulations simultaneously either reduced or increased the sink size (seeds m−2) while altering the source availability. If the manipulated plants were assumed to have a similar sink size to the control, shading would have decreased MSW by 16–22%. Similarly, the full defoliation after full flowering decreased MSW by 27% and the defoliation at the vegetative stage by 11%. On the contrary, supplemental irrigation would have increased MSW by 8–21%. The decrease in MSW in the downward-manipulation of source availability and the increase in MSW in the upward-manipulation of source availability indicate that canola yield was driven by source availability during seed filling period. However, yield reduction from shading at flowering indicates that yield could be limited by sink size established during flowering. Therefore, agronomic management and future breeding should be directed to increase assimilates available to the crop from flowering onwards.
Numerous of lithium ion battery fires or explosions enhance the need of fire control technology. To investigate the effectiveness of depressurization on the fire suppression of lithium ion batteries ...in an aircraft environment, an experimental and theoretical study is taken on the ignition and combustion characteristics of lithium ion batteries under an incident heat flux of 50 kW/m2 using a low pressure tank. Several fire parameters are measured and analyzed, including time to deflation, ignition and thermal runaway, surface and flame temperatures as well as average mass loss rate. Experimental results show the average mass loss rate and surface and the peak flame temperatures decrease whereas the time to deflation, ignition and thermal runaway increase with the reduction of the pressure, demonstrating a lower fire risk. The 30 kPa is the critical pressure for the ignition of lithium ion battery under 50 kW/m2 radiation heat flux. However, the pressure shows limited influence on the ignition temperature, radiation coefficient and time interval between the time to ignition and thermal runaway. The effect mechanisms of pressure on fire parameters are revealed. An empirical model is developed to predict the average mass loss rate of lithium ion battery under low atmospheric pressure.
•Ignition and combustion characteristics of battery at low pressure are studied.•Low pressure extends ignition time and weakens burning intensity of battery.•The 30 kPa is the critical pressure for battery ignition under 50 kW/m2 heat flux.•The effect mechanisms of pressure on combustion characteristics are revealed.•A correlation predicting the average mass loss rate of battery is developed.
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•Glass-fiber reinforced aerogels showed remarkable mechanical strength and flexibility compared with pure aerogel powders.•The hybrid aerogel showed superhydrophobicity, great thermal ...stability and low thermal conductivity.•The MTMS/water glass hybrid aerogels were prepared via freeze drying without further surface modification.•The molar ratio of MTMS/water glass could significantly influence the properties of composite.
In order to maintain the integrity, glass fiber (GF) reinforced silica aerogel composites were synthesized using methltrimethoxysilane (MTMS) and water glass co-precursor by freeze drying method. The composites were characterized by scanning electron microscopy, Brunauer-Emmett-Teller analysis, uniaxial compressive test, three-point bending test, thermal conductivity analysis, contact angle test, TG-DSC analysis. It was found that the molar ratio of MTMS/water glass could significantly affect the properties of composites. The bulk density and thermal conductivity first decreased and then increased with the increasing molar ratio. The composites showed remarkable mechanical strength and flexibility compared with pure silica aerogel. Moreover, when the molar ratio is 1.8, the composites showed high specific surface area (870.9 m2/g), high contact angle (150°), great thermal stability (560 °C) and low thermal conductivity (0.0248 W/m·K). These outstanding properties indicate that GF/aerogels have broad prospects in the field of thermal insulation.
The thermal conductivity of highly porous mullite materials (from 72 to 86vol% porosity) has been measured by the transient plane source (TPS) technique at room temperature. These materials were ...fabricated by foaming and starch consolidation and showed similar microstructures with different porosities. From the point of view of heat conduction, these materials can be considered as a two-phase system, viz. a dense mullite skeleton and air, and their thermal conductivities describe heat transfer through these composite materials. Through comparing experimental data and predicted values derived from theoretical models, these materials can be classified as “internal porosity” materials and their thermal conductivities are bounded between the Maxwell–Eucken 1 model and the effective medium theory (EMT) equation. Then the porosity dependence of thermal conductivity was modeled by a simple model which assumes that components were contained in a uniform medium with thermal conductivity km.
Breast milk is the main source of nutrition for infants; it contains considerable microflora that can be transmitted to the infant endogenously or by breastfeeding, and it plays an important role in ...the maturation and development of the immune system. In this study, we isolated and identified lactic acid bacteria (LAB) from human colostrum, and screened 2 strains with probiotic potential. The LAB isolated from 40 human colostrum samples belonged to 5 genera: Lactobacillus, Bifidobacterium, Streptococcus, Enterococcus, and Staphylococcus. We also isolated Propionibacterium and Actinomyces. We identified a total of 197 strains of LAB derived from human colostrum based on their morphology and 16S rRNA sequence, among them 8 strains of Bifidobacterium and 10 strains of Lactobacillus, including 3 Bifidobacterium species and 4 Lactobacillus species. The physiological and biochemical characteristics of strains with good probiotic characteristics were evaluated. The tolerances of some of the Bifidobacterium and Lactobacillus strains to gastrointestinal fluid and bile salts were evaluated in vitro, using the probiotic strains Bifidobacterium lactis BB12 and Lactobacillus rhamnosus GG as controls. Among them, B. lactis Probio-M8 and L. rhamnosus Probio-M9 showed survival rates of 97.25 and 78.33% after digestion for 11 h in artificial gastrointestinal juice, and they exhibited growth delays of 0.95 and 1.87 h, respectively, in 0.3% bile salts. These two strains have the potential for application as probiotics and will facilitate functional studies of probiotics in breast milk and the development of human milk-derived probiotics.
Structural profiling of healthy human gut microbiota across heterogeneous populations is necessary for benchmarking and characterizing the potential ecosystem services provided by particular gut ...symbionts for maintaining the health of their hosts. Here we performed a large structural survey of fecal microbiota in 314 healthy young adults, covering 20 rural and urban cohorts from 7 ethnic groups living in 9 provinces throughout China. Canonical analysis of unweighted UniFrac principal coordinates clustered the subjects mainly by their ethnicities/geography and less so by lifestyles. Nine predominant genera, all of which are known to contain short-chain fatty acid producers, co-occurred in all individuals and collectively represented nearly half of the total sequences. Interestingly, species-level compositional profiles within these nine genera still discriminated the subjects according to their ethnicities/geography and lifestyles. Therefore, a phylogenetically diverse core of gut microbiota at the genus level may be commonly shared by distinctive healthy populations as functionally indispensable ecosystem service providers for the hosts.
Abstract Objective Probiotics may improve intestinal health by modulating intestinal microbiota. However, the age-related variation in response to probiotic consumption is understudied. The aim of ...this study was to determine the effect of oral consumption of Lactobacillus plantarum P-8 ( Lp -8) on human intestinal microflora, secretary immunoglobulin A (SIgA), total bile acids (TBAs), and short-chain fatty acids (SCFAs) of different aged adults. Methods Thirty-three recruited individuals, including young (mean age 26 y), middle-aged (mean age 51 y), and elderly (mean age 76 y) volunteers, were given a single daily oral dose of Lp -8 (6 × 1010 colony forming units) for 4 wk. Fecal samples were collected before starting, during, and after stopping Lp -8 intake. Polymerase chain reaction (PCR)-denaturing gradient gel electrophoresis, quantitative PCR, high-performance liquid chromatography, and enzyme-linked immunosorbent assay were used to detect for fecal microflora, SIgA, TBAs, and SCFAs. Results Results showed an increase in Bifidobacterium ( P < 0.05) and other beneficial bacteria, whereas Desulfovibrio ( P < 0.05) and other opportunistic pathogens decreased after taking Lp -8 for 4 wk. Lp -8 consumption also affected fecal levels of SIgA, TBAs, and SCFAs. Conclusions Lp -8 administration could improve human gastrointestinal health. However, some of these effects were transient and gradually disappeared once the intervention was discontinued. Moreover, the extent of these desirable effects was age-related.
Numerous of lithium ion battery fires and explosions enhance the need of precise risk assessments on batteries. In the current study, 18650 lithium ion batteries at different states of charge are ...tested using a cone calorimeter to study the burning behaviors under an incident heat flux of 50 kW m super(-2). Several parameters are measured, including mass loss rate, time to ignition, time to explosion, heat release rate (HRR), the surface temperature and concentration of toxic gases. Although small quantities of oxygen are released from the lithium ion battery during burning, it is estimated that the energy, consuming oxygen released from the lithium ion battery, accounts for less than 13% of total energy released by a fully charged lithium ion battery. The experimental results show that the peak HRR and concentration of toxic gases rise with the increasing the states of charge, whereas the time to ignition and time to explosion decrease. The test results of the fully charged lithium ion batteries at three different incident heat fluxes show that the peak HRR increases from 6.2 to 9.1 kW and the maximum surface temperature increases from 662 to 934 degreesC as the incident heat flux increases from 30 to 60 kW m super(-2).
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