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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]

Root reinforcement is an effective slope protection measure due to root water absorption and soil suction. However, the coupled effect of rainfall and root reinforcement remains unclear, resulting in a challenge to evaluate slope stability in complex environments. This paper regards the root–soil composite as a natural fiber composite and quantifies its reinforcement effect using direct shear tests. The unsaturated soil seepage–stress theory was employed to simulate the effect of rainfall on water migration and the stability of spoil, overburden, and vegetated slopes. Field measurements and pore water pressure tests verified the simulation results. Furthermore, the influences of the slope angle, rainfall parameters, and vegetation cover thickness on slope stability were analyzed. The results showed the following: (1) The root reinforcement enhanced the soil's ability to resist shear deformation, substantially improving soil shear strength. The cohesion of the root–soil composite (crs = 33.25 kPa) was 177% higher than that of the engineering spoil (ces = 12 kPa) and 32.21% higher than that of the overburden soil (cos = 25.15 kPa). (2) The overburden and vegetated slopes had lower permeability coefficients and a higher shear strength than the spoil slope, and the effect was more pronounced for the latter, resulting in lower landslide risks. The water migration trend of the vegetated slope was characterized by substantial runoff and a low sediment yield. The safety factors of the spoil slope, overburden slope, and vegetated slope were 1.741, 1.763, and 1.784 before rainfall and 1.687, 1.720, and 1.763 after rainfall, respectively, indicating a significantly higher safety factor of the vegetated slope after rainfall. (3) The slope angle significantly affected slope stability, with lower safety factors observed for higher rainfall intensities and durations. Under these conditions, the slope angle should be less than 30°, and the soil thickness should be 0.5 m for herbaceous vegetation and shrubs and 1.0 m for trees. [ABSTRACT FROM AUTHOR]

A large alpine meadow in a seasonal permafrost zone exists in the west of Sichuan, which belongs to a part of the Qinghai–Tibet Plateau, China. Due to the extreme climates and repeated freeze–thaw cycling, resulting in a diminishment in soil shear strength, disasters occur frequently. Plant roots increase the complexity of the soil freeze–thaw strength problem. This study applied the freeze–thaw cycle and direct shear tests to investigate the change in the shear strength of root-soil composite under freeze–thaw cycles. This study examined how freeze–thaw cycles and initial moisture content affect the shear strength of two sorts of soil: uncovered soil and root-soil composite. By analyzing the test information, the analysts created numerical conditions to foresee the shear quality of both sorts of soil under shifting freeze–thaw times and starting moisture levels. The results showed that: (1) Compared to the bare soil, the root-soil composite was less affected by freeze–thaw cycles in the early stage, and the shear strength of both sorts of soil was stabilized after 3–5 freeze–thaw cycles. (2) The cohesion of bare soil decreased more than that of root-soil composite with increasing moisture content. However, freeze–thaw cycles primarily influence soil cohesion more than the internal friction angle. The cohesion modification leads to changes in shear quality for both uncovered soil and root-soil composite. (3) The fitting equations obtained via experiments were used to simulate direct shear tests. The numerical results are compared with the experimental data. The difference in the soil cohesion and root-soil composite cohesion between the experiment data and the simulated result is 8.2% and 17.2%, respectively, which indicates the feasibility of the fitting equations applied to the numerical simulation of the soil and root-soil composite under the freeze–thaw process. The findings give potential applications on engineering and disaster prevention in alpine regions. [ABSTRACT FROM AUTHOR]

To investigate the changes of the main ingredients in black garlic (BG) during fermentation, the contents of moisture, total acids and reducing sugars were determined. Allicin, 5-Hydroxymethylfurfural (5-HMF), and total phenols were also determined as bioactive substances. DPPH scavenging capacity was determined to indicate the antioxidant activity of BG. The changes in hardness and color were detected as well. The results showed that the moisture content decreased from 66.13% to 25.8% during the fermentation. The content of total acids, total phenols, and reducing sugars increased from 0.03 g/g to 0.29 g/g, from 0.045 μg/g to 0.117 μg/g, and from 0.016 g/g to 0.406 g/g, respectively. The content of 5-HMF increased from 0 to 4.12 μg/mL continuously, while the content of allicin increased from 0.09 mmol/100 g to 0.30 mmol/100 g and then decayed to 0.00 mmol/100 g. The L*, a*, and b* values of BG were 23.65 ± 0.44, 0.64 ± 0.06, and 0.85 ± 0.05, respectively. There was a higher intensity of dark color in BG than that in fresh garlic. The hardness values decreased first and then increased in later fermentation from 465.47 g to 27,292.38 g. Principal component analysis (PCA) showed that the samples were divided into three clusters, including cluster1 (fresh garlic, S0), cluster2 (S1), and cluster3 (S3−S9). This research effectively clarified the various stage of the BG fermentation process, and it is expected to supply references for reducing production time in industrial BG fermentation. [ABSTRACT FROM AUTHOR]

Background Passive-active immunoprophylaxis against mother-to-child transmission (MTCT) of hepatitis B virus (HBV) recommends administering hepatitis B immunoglobulin (HBIG) and birth-dose hepatitis B vaccine in infants within 12 or 24 hours after birth. With this protocol, MTCT of HBV still occurs in 5–10% infants of HBV-infected mothers with positive hepatitis B e antigen (HBeAg). The present study aimed to investigate whether earlier administration of HBIG and hepatitis B vaccine after birth can further increase protection efficacy. Methods We conducted a prospective, multi-center observational study in infants born to mothers with HBV infection, in whom neonatal HBIG and birth dose hepatitis B vaccine were administered within one hour after birth. The infants were followed up for HBV markers at 7–14 months of age. Results A total of 1140 pregnant women with HBV were enrolled, and 982 infants (9 twins) of 973 mothers were followed up at 9.6 ± 1.9 months of age. HBIG and birth-dose vaccine were administered in newborn infants within a median of 0.17 (0.02–1.0) hours after birth. The overall rate of MTCT was 0.9% (9/982), with none (0%) of the 607 infants of HBeAg-negative mothers and 9 (2.4%) of 375 infants of HBeAg-positive mothers acquiring HBV. All 9 HBV-infected infants were born to mothers with HBV DNA >2.75 × 106 IU/mL. Maternal HBV DNA levels >2 × 106 IU/mL were an independent risk factor (odds ratio, 10.627; 95% confidence interval, 2.135–∞) for immunoprophylaxis failure. Conclusions Earlier use (within 1 hour after birth) of HBIG and hepatitis B vaccine can provide better protection efficacy against MTCT of HBV. [ABSTRACT FROM AUTHOR]

Saxitoxin is one of the most harmful paralytic shellfish toxins due to its high toxicity and adverse effects on the environment and human health. Aptasensors provide simple detection procedures because they have the advantages of chemical stability, easy synthesis and modification, and high convenience in signal transformation. Surface-enhanced Raman scattering (SERS) is an analytical technique that amplifies the analytical signals of molecules at extremely low concentrations, or even at the single molecule level, when the analyte is very close to rough metal surfaces or nanostructures. In this study, an SERS aptasensor is reported for the determination of saxitoxin for the first time. The optimized saxitoxin aptamer (M-30f) was modified on gold nanoparticles and served as the recognition element. Crystal violet was used as the Raman reporter without chemical bounding. The analytical principles of the aptasensor are that saxitoxin destabilized the conformations of the aptamer at high temperature conditions and altered the binding of crystal violet on the gold nanoparticles. In the presence of saxitoxin, the conformation of aptamer containing the G-quadruplex that selectively bound crystal violet unfolded to a large extent and hence the crystal violet molecules were released from gold nanoparticles with a reduced SERS signal. The effects of the gold nanoparticle size, the amount of DNA, aptamer density, sodium chloride concentration, and operation temperature upon the SERS determination were optimized. The resulting simple SERS aptasensor was developed with a satisfactory limit of detection (11.7 nM) and selectivity. The application for the analysis of real shellfish samples with simple procedures demonstrates that this SERS aptasensor is promising for on-site applications. [ABSTRACT FROM AUTHOR]

Many reported synthetic methods for hollow porous carbon dodecahedrons based on a templating strategy are relatively complex, and the obtained hollow structure is usually single shell. Herein, we propose a multi-layered zeolitic imidazolate framework based self-templated synthesis of nitrogen-doped hollow porous carbon dodecahedrons with various architectures such as single-shell, double-shell, yolk–shell and yolk-double-shell. The mechanism of formation of the hollow structure is also demonstrated and it indicates that our strategy can be extended to prepare more multi-shell or yolk-multi-shell nitrogen-doped hollow porous carbon dodecahedrons. All obtained nitrogen-doped hollow porous carbon dodecahedrons are employed as electroactive materials for the construction of supercapacitor electrodes. Owing to their hierarchical micro/mesoporous structure, high nitrogen doping, large surface area, graphitic structure, and the unique yolk-double-shell hollow structure, nitrogen-doped yolk-double-shell hollow porous carbon dodecahedrons (N-YDS-HPCDs) exhibit a distinguished capacitance of 346 F g−1 at a current density of 0.5 A g−1, excellent stability with approximately 93% capacitance retention after 10 000 cycles, and a high energy density of 11.64 W h kg−1 at a power density of 250 W kg−1. [ABSTRACT FROM AUTHOR]

In order to realize the multi-analyte assays for environmental contaminants, an optical biosensor utilizing laser-induced fluorescence-based detection via the binding of biomolecules to the surface of an integrated TriPleX™ waveguide chip on a glass substrate (fused silica, FS) is described. As far as we know, this is the first demonstration of using the TriPleX™ technology to fabricate the waveguide chip on a FS substrate. The sensor consists of 32 individually addressable sensor patches, which were formed on the chip surface by exploiting 3 Y-junction splitters, creating four equal rows of eight evanescently excited windows in parallel. The basic low-loss SiO 2 /Si 3 N 4 TriPleX™ waveguide configuration in combination with on-chip spotsize convertors allows for both high fiber-to-chip coupling efficiency and enables at the same time individually optimized high chip surface intensity and low patch-to-patch deviation. Moreover, the complementary metal-oxide-semiconductor compatible fabrication of waveguide chip allows for its mass production at low cost. By taking MC-LR, 2,4-D, atrazine and BPA as the model analytes, the as-proposed waveguide based biosensor was proven sensitive with the detection limits of 0.22 μg/L for MC-LR, 1.18 μg/L for 2, 4-D, 0.2 μg/L for atrazine and 0.06 μg/L for BPA. Recoveries of the biosensor towards simultaneous detection of MC-LR, 2, 4-D, atrazine and BPA in spiked real water samples varied from 84% to 120%, indicating the satisfactory accuracy of the established technology. [ABSTRACT FROM AUTHOR]