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In order to improve soy sauce koji making technology and to stabilize its quality, high-throughput sequencing and headspace solid-phase microextraction coupled with gas chromatography-mass spectrometry (HS-SPME-GC-MS) were used to analyze the microbial community succession and the changes of total acid, moisture, protease, glucoamylase, amylase and volatile flavor substances during the fermentation of soy sauce koji, and the correlation between microbial community succession and volatile flavor substances was investigated. The results showed that 10 bacterial genera with relative abundance greater than 1% including Weissella, Staphylococcus and Lactobacillus, and three fungal genera with relative abundance greater than 1% including Kodamaea, Aspergillus and Candida were identified, with Weissella, Kodamaea and Aspergillus being dominant throughout the whole fermentation period. With the increase in fermentation time, the moisture content decreased, the total acid content and the activities of protease, amylase and glucoamylase increased, and the total content of volatile flavor substances showed an increasing trend, reaching 4 381.31 μg/100 g at the end of fermentation (48 h). Correlation analysis showed that dominant microorganisms, such as Weissella, Lactobacillus and Kodamaea, affected the activities of protease, glucoamylase and amylase, and significantly influenced the formation of various volatile flavor substances, such as alcohols, aldehydes, esters, acids and pyrazines. This study provides a scientific basis and theoretical foundation for the improvement of the quality of soy sauce koji and the development of koji making technology.

[Objective] The Qinghai-Tibetan Plateau is an important ecological barrier in China, and alpine meadows are an important part of it, and the function of soil and water conservation is an important ecological service function of alpine meadows. Therefore, it is of great significance to carry out the study of soil erosion process in alpine meadows on the Tibetan Plateau to reduce anthropogenic disturbance of soil erosion and to safeguard the ecological security of the southwest region. [Methods] In this study, five different types of slopes, namely, undegraded, mildly degraded, moderately degraded, bare slopes and artificially restored slopes in alpine meadows of the Tibetan Plateau, were selected to analyze the process of flow and sand production on degraded and restored slopes under different rainfall intensities, and to reveal the relationship between the erosion mechanism and water-sand relationship between degraded slopes and restored slopes with artificial vegetation through the simulated rainfall test in the field. [Results] (1) The initial flow production time is relatively short on the undegraded slopes of alpine meadows and the restored slopes with artificial vegetation because of their dense root system, and the water infiltration ability is relatively weak; while on the mildly degraded slopes, the lateral flow and vertical infiltration ability are relatively strong, and the initial flow production time is relatively long. (2) Under regular rainfall conditions (30 and 60 mm/h), the flow rate of mildly degraded slopes is the smallest, and the flow reduction benefit is the highest, reaching 77.13%, the flow rate of artificially restored slopes is close to that of undegraded slopes and is slightly higher than that of mildly degraded slopes; the cumulative flow rate of bare soil slopes is the largest, and it is significantly higher than other slopes; the flow rate of undegraded slopes under extreme rainfall conditions (90 mm/h) is surging, only lower than that of bare slopes and significantly higher than other slopes. Under extreme rainfall conditions (90 mm/h), the flow rate of undegraded slopes increased, which was only lower than that of bare slopes and significantly higher than that of artificially restored slopes. (3) Under regular rainfall conditions (30 and 60 mm/h), the sand reduction benefit of the artificially restored vegetated slopes was the highest, reaching 81.97% and 89.82%, followed by the undegraded slopes, and with the increase of the degradation degree of the vegetation, the sand reduction benefit was gradually reduced; however, under extreme rainfall conditions, the sand reduction benefit of the artificially restored vegetation and the undegraded slopes was almost the same, and the sand production of the moderately degraded slopes was higher than the undegraded slopes, which is significantly higher than the other slopes. However, under extreme rainfall conditions, the sand reduction benefits of artificially restored vegetation and undegraded slopes are almost the same, while the sand production of moderately degraded slopes is 4.59 times of that of undegraded slopes. [Conclusion] The results of these studies can provide important scientific basis for vegetation restoration and ecological security in alpine meadow area.

Background: Group B Streptococcus (GBS) colonization is one of the major causes of severe neonatal infections. The study was intended to identify GBS colonization in pregnant women, explore its potential risk factors, and analyze the impact of GBS on outcomes for both mothers and newborns. Material and Methods: A retrospective research was carried out on pregnant women who had undergone GBS screening and delivered from June 2020 to December 2022. Pregnant women between 35 and 37 weeks of gestation had GBS screening using real-time polymerase chain reaction (RT-PCR). The clinical characteristics and outcomes of mothers and newborns were collected. The risk factors linked to maternal GBS colonization and its impact on adverse outcomes for mothers and neonates were assessed using chi-square and logistic regression analyses. The composite neonatal adverse outcomes included low Apgar scores, neonatal pneumonia, neonatal hyperbilirubinemia, neonatal sepsis, or low birth weight. Results: Overall, the rate of GBS positivity was 10.63% (551/5183), and the rate of maternal GBS screening was 88.4%. Diabetic pregnant women were more likely to become colonized with GBS. Our research revealed that GBS carriers experienced higher rates of fetal distress and neonatal adverse outcomes than non-GBS carriers. Fetal distress (OR, 1.940; 95% CI, 1.355 to 2.778, P < 0.001), neonatal sepsis (OR, 5.063; 95% CI, 2.536–10.109, P < 0.001), low Apgar scores (OR, 2.097; 95% CI, 1.184–3.715, P = 0.011), neonatal pneumonia (OR, 1.638; 95% CI, 1.039 to 2.582, P = 0.034) and neonatal hyperbilirubinemia (OR, 1.438; 95% CI, 1.080 to 1.915, P = 0.013) were significantly related to maternal GBS colonization. When we used the composite adverse neonatal outcomes as the dependent variable and analyzed the influencing factors, the logistic regression analysis revealed that GBS colonization was still significantly related to an elevated risk of adverse neonatal outcomes (OR = 1.752, 95% CI, 1.389–2.208; P < 0.001). Conclusions: Diabetes may be a risk factor for maternal GBS colonization. Moreover, in this study, GBS colonization correlated with neonatal adverse outcomes but not with maternal outcomes. [ABSTRACT FROM AUTHOR]

The volatile fatty acids (VFAs) productions, as well as particulate organics decomposition, soluble chemical oxygen demand (SCOD) yield, and the VFAs production pathways from mesophilic and thermophilic anaerobic fermentation in waste activated sludge were investigated. Batch experiments showed that the decomposition rate of volatile suspended solids (VSS), particulate carbohydrate (P–C) and particulate protein (P–P) followed the first-order kinetic model at different temperatures. However, the intermediates, accumulated in the process of protein or carbohydrate digestion had a more significant inhibitory effect on the production of VFAs during the mesophilic anaerobic acidification process. The production of VFAs by thermophilic anaerobic fermentation is 2086.05 mg COD/L, which is about twice the production under mesophilic conditions. Among them, the concentration and proportion of high molecular weight organic acids such as isobutyric acid (320.29 mgCOD/L) and isovaleric acid (745.75 mgCOD/L) are relatively high. Then 13C stable isotope labelling experiment demonstrated that, the decomposition of carbohydrates yields 77% acetic acid and 86% butyric acid, while protein breakdown produces 85% propionic acid and 99% valeric acid. This confirms that carbohydrates are more favourable for the formation of even-carbon organic acids, while proteins tend to yield odd-carbon organic acids. Additionally, this helps refine the pathway for valeric acid formation during anaerobic acidogenesis. [ABSTRACT FROM AUTHOR]

Magnetic CuFe2O4 was prepared with the modified sol–gel method and used for enhanced peroxymonosulfate (PMS) activation and ofloxacin (OFL) degradation. The OFL could almost degrade within 30 min at a catalyst dosage of 0.66 g/L, PMS concentration of 0.38 mM, and initial pH of 6.53 without adjustment, using response surface methodology (RSM) with Box-Behnken design (BBD). In the CuFe2O4/PMS system, the coexisting substances, including CO32−, NO3−, SO42−, Cl− and humic acid, have little effect on the OFL degradation. The system also performs well in actual water, such as tap water and surface water (Mei Lake), indicating the excellent anti-interference ability of the system. The cyclic transformation between Cu(II)/Cu(I) and Fe(III)/Fe(II) triggers the generation of active radicals including SO4•−, •OH, •O2− and 1O2. The OFL degradation pathway, mainly involving the dehydrogenation, deamination, hydroxylation, decarboxylation and carboxylation processes, was proposed using mass spectroscopy. Moreover, the toxicity assessment indicated that the end intermediates are environmentally friendly. This study is about how the CuFe2O4/PMS system performs well in PMS activation for refractory organic matter removal in wastewater. [ABSTRACT FROM AUTHOR]

Pear residue, a byproduct of pear juice extraction, is rich in soluble sugar, vitamins, minerals, and cellulose. This study utilized Monascus anka in liquid fermentation to extract dietary fiber (DF) from pear residue, and the structural and functional characteristics of the DF were analyzed. Soluble DF (SDF) content was increased from 7.9/100 g to 12.6 g/100 g, with a reduction of average particle size from 532.4 to 383.0 nm by fermenting with M. anka. Scanning electron microscopy and infrared spectroscopic analysis revealed more porous and looser structures in Monascus pear residue DF (MPDF). Water‐, oil‐holding, and swelling capacities of MPDF were also enhanced. UV–visible spectral analysis showed that the yield of yellow pigment in Monascus pear residue fermentation broth (MPFB) was slightly higher than that in the Monascus blank control fermentation broth. The citrinin content in MPFB and M. anka seed broth was 0.90 and 0.98 ug/mL, respectively. Therefore, liquid fermentation with M. anka improved the structural and functional properties of MPDF, suggesting its potential as a functional ingredient in food. [ABSTRACT FROM AUTHOR]

Coal-fired power plant is a major contributor to greenhouse gas emissions. The post-combustion capture is a promising method for CO2 emission reduction but the high thermal demand is unbearable. To address this issue, solar thermal energy and CO2 capture are jointly integrated into the coal-fired power plant in this study. The solar thermal energy is employed to meet the heat requirement of the CO2 capture process, thereby avoiding the electricity loss caused by self-driven CO2 capture. Furthermore, the heat released from the carbonation reaction of MgO adsorbent is integrated into the steam Rankine cycle. By partially substituting the extracted steam for feedwater heating, the electricity output of the power plant is further increased. According to the results from the developed model, the system could achieve a CO2 capture rate of 86.5% and an electricity output enhancement of 9.8% compared to the reference system, which consists of a self-driven CO2 capture coal-fired power plant and PV generation unit. The operational strategy is also optimized and the amount of CO2 emission reduction on a typical day is increased by 11.06%. This work shows a way to combine fossil fuels and renewable energy for low carbon emissions and efficient power generation. [ABSTRACT FROM AUTHOR]