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Soil thermal conductivity in the near-phase-transition zone is a key parameter affecting the thermal stability of permafrost engineering and its catastrophic thermal processes. Therefore, accurately determining the soil thermal conductivity in this specific temperature zone has important theoretical and engineering significance. In the present work, a method for testing the thermal conductivity of fine sandy soil in the near-phase-transition zone was proposed by measuring thermal conductivity with the transient plane heat source method and determining the volumetric specific heat capacity by weighing unfrozen water contents. The unfrozen water content of sand specimens in the near-phase-transition zone was tested, and a corresponding empirical fitting formula was established. Finally, based on the testing results, temperature variation trends and parameter influence laws of thermal conductivity in the near-phase-transition zone were analyzed, and thermal conductivity prediction models based on multiple regression (MR) and a radial basis function neural network (RBFNN) were also established. The results show the following: (1) The average error of the proposed test method in this work and the reference steady-state heat flow method is only 7.25%, which validates the reliability of the proposed test method. (2) The variation in unfrozen water contents in fine sandy soil in the range of 0~−3 °C accounts for over 80% of the variation in the entire negative temperature range. The unfrozen water content and thermal conductivity curves exhibit a similar trend, and the near-phase-transition zone can be divided into a drastic phase transition zone and a stable phase transition zone. (3) Increases in the thermal conductivity of fine sandy soil mainly occur the drastic phase transition zone, where these increases account for about 60% of the total increase in thermal conductivity in the entire negative temperature region. With the increase in density and total water content, the rate of increase in thermal conductivity in the drastic phase transition zone gradually decreases. (4) The R2, MAE, and RSME of the RBFNN model in the drastic phase transition zone are 0.991, 0.011, and 0.021, respectively, which are better than those of the MR prediction model. [ABSTRACT FROM AUTHOR]

Simple Summary: Fermentation not only reduces the anti-nutritional factors in soybean meal, but also increases the contents of bioactive peptides and free amino acids, and promotes the digestibility of nutrients in soybean meal for growing pigs. The enzymes and prebiotics contained in fermented soybean meal (FSBM) improve the intestinal health, antioxidant capacity, and immune function of animals. However, there is a lack of systematic evaluation of the nutritional value of FSBM for growing pigs. Therefore, we selected 10 representative FSBM samples from nine different manufacturers in China, and determined the digestible energy (DE), metabolizable energy (ME), and standardized ileal digestibility (SID) of amino acids (AA) of FSBM. We found that the mean values of DE, ME, and SID of AA in the FSBM samples were similar to those of NRC (2012), but the variation was large. The DE and ME values can be predicted based on the chemical composition of FSBM in growing pigs. This study aimed to evaluate the digestible energy (DE), metabolizable energy (ME), and standardized ileal digestibility (SID) of amino acids (AA) in fermented soybean meal (FSBM) fed to growing pigs. In experiment 1, twenty-two growing pigs (Duroc × Landrace × Yorkshire; 32.0 ± 4.2 kg BW) were fed one of 11 diets in a replicated 11 × 3 incomplete Latin square design to determine the DE and ME of FSBM. The diets included a corn-based diet and 10 experimental diets formulated by replacing the corn with 29.10% FSBM. In experiment 2, eleven growing pigs (Duroc × Landrace × Yorkshire; 24.3 ± 2.3 kg BW) were surgically equipped with a T-cannula and arranged in an 11 × 6 incomplete Latin square design with 11 diets and six periods. The diets included an N-free diet and 10 experimental diets containing 40% FSBM as the sole source of AA. The results showed that the contents of dry matter (DM), gross energy, crude protein, crude fiber, neutral detergent fiber, acid detergent fiber, calcium, and phosphorus averaged 91.83% (ranging from 89.24 to 94.55%), 18.44 MJ/kg (ranging from 18.00 to 18.95 MJ/kg), 50.63% (ranging from 50.00 to 51.81%), 4.51% (ranging from 3.41 to 5.40%), 9.17% (ranging from 7.02 to 10.30%), 6.38% (ranging from 4.97 to 7.45%), 0.32% (ranging from 0.29 to 0.34%), and 0.67% (ranging from 0.61 to 0.84%), respectively. The average DE and ME were 17.55 and 16.33 MJ/kg DM, respectively, with ranges of 15.72 to 18.80 MJ/kg DM and 14.30 to 17.72 MJ/kg DM, respectively. Significant differences were observed in the SID of essential AA (p < 0.05), except for Thr and Arg. The SID of Lys, Met, Trp, and Thr ranged from 68.13 to 83.27% (mean = 76.62%), 62.23 to 89.30% (mean = 75.25%), 72.30 to 90.29% (mean = 80.96%), and 74.17 to 84.41% (mean = 77.90%), respectively. These results indicate significant variability in chemical composition, energy content, and the SID of AA among the selected FSBM samples. The chemical composition of FSBM can be used to predict DE and ME values. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION Bacillus inaquosorum strains is widely recognized for their plant‐growth‐promoting and biocontrol capabilities, yet their roles in protease production remain unclear. The present study aimed to comprehensively assess the protease‐producing performance of B. inaquosorum strain E1‐8, at the same time as exploring the novel application of agricultural Bacillus proteases in the preparation of protein hydrolysates for fresh‐cut fruits preservation.First, genomic sequencing revealed the diversity of E1‐8 proteases, indicating 15 putative extracellular proteases. Subsequently, the fermentation conditions for E1‐8 protease production were optimized, with sweet potato powder and soybean meal identified as the most suitable carbon and nitrogen sources, respectively, resulting in a maximum protease activity of 321.48 U mL−1. Upon culturing the strain under these optimized conditions, only an S8 family serine protease and an M48 family metalloprotease were revealed by secretomic analysis and protease inhibitor assays. Additionally, the optimal protease conditions for generating protein hydrolysates from soy, pea, fish and porcine proteins were determined. The molecular weight of the hydrolysates primarily ranged from 2000 to 180 Da, with a total of 17 amino acids identified. The application of these hydrolysates demonstrated a 2,2‐diphenyl‐1‐picrylhydrazyl (i.e. DPPH) scavenging activity ranging from 58.64% to 84.12%, significantly reducing of the melting peaks and the freezing points. Furthermore, the browning index of apple slices stored at 4 °C decreased by 14.81% to 22.15% on the second day, and similar effects were observed in fresh‐cut banana stored at 4 °C for 7 days.The protein hydrolysates obtained exhibit remarkable antioxidant, antifreeze and anti‐browning properties for fresh‐cut fruits. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Invasive pulmonary aspergillosis (IPA) in patients with diabetes mellitus has high incidence, especially in Type 2 diabetes mellitus (T2DM). The aim of this study was to evaluate the diagnostic efficacy of metagenomic next-generation sequencing (mNGS) for IPA in patients with T2DM. A total of 66 patients with T2DM were included, including 21 IPA and 45 non-IPA patients, from January 2022 to December 2022. The demographic characteristics, comorbidities, laboratory test results, antibiotic treatment response, and 30-day mortality rate of patients were analyzed. The diagnostic accuracy of mNGS and conventional methods was compared, including sensitivity, specificity, positive predictive value and negative predictive value. The sensitivity and specificity of mNGS were 66.7% and 100.0%, respectively, which were significantly higher than those of fluorescence staining (42.1% and 100%), serum 1,3-β-D-glucan detection (38.1% and 90.9%), serum galactomannan detection (14.3% and 94.9%) and BALF galactomannan detection (47.3% and 70.7%). Although the sensitivity of BALF culture (75.0%) was higher than that of mNGS (66.7%), the turnover time of mNGS was significantly shorter than that of traditional culture (1.6 days vs. 5.0 days). The sensitivity of mNGS combined with BALF culture reached 100.0%. In addition, mNGS has a stronger ability to detect co-pathogens with IPA. 47.6% of T2DM patients with IPA were adjusted the initial antimicrobial therapy according to the mNGS results. This is the first study to focus on the diagnostic performance of mNGS in IPA infection in T2DM patients. MNGS can be used as a supplement to conventional methods for the diagnosis of IPA in patients with T2DM. [ABSTRACT FROM AUTHOR]

This study reports the whole-genome sequence of Lactiplantibacillus plantarum cqf-43 isolated from healthy sow feces. Based on genomic analysis, we performed a comprehensive safety assessment of strain cqf-43, using both in vitro and in vivo experiments, and explored its probiotic potential. The total genome length measures 3,169,201 bp, boasting a GC content of 44.59%. Through phylogenetic analyses, leveraging both 16S rRNA gene and whole-genome sequences, we confidently categorize strain cqf-43 as a member of Lactiplantibacillus. Genome annotation using Prokka unveiled a total of 3141 genes, encompassing 2990 protein-coding sequences, 71 tRNAs, 16 rRNAs, and 1 tmRNA. Functional annotations derived from COG and KEGG databases highlighted a significant abundance of genes related to metabolism, with a notable emphasis on carbohydrate utilization. The genome also revealed the presence of prophage regions and CRISPR-Cas regions while lacking virulence and toxin genes. Screening for antibiotic resistance genes via the CARD database yielded no detectable transferable resistance genes, effectively eliminating the potential for harmful gene transfer. It is worth highlighting that the virulence factors identified via the VFDB database primarily contribute to bolstering pathogen resilience in hostile environments. This characteristic is particularly advantageous for probiotics. Furthermore, the genome is devoid of menacing genes such as hemolysin, gelatinase, and biogenic amine-producing genes. Our investigation also unveiled the presence of three unannotated secondary metabolite biosynthetic gene clusters, as detected by the online tool antiSMASH, suggesting a great deal of unknown potential for this strain. Rigorous in vitro experiments confirmed tolerance of strain cqf-43 in the intestinal environment, its antimicrobial efficacy, sensitivity to antibiotics, absence of hemolysis and gelatinase activity, and its inability to produce biogenic amines. In addition, a 28-day oral toxicity test showed that the strain cqf-43 did not pose a health hazard in mice, further establishing it as a safe strain. [ABSTRACT FROM AUTHOR]

The present study investigated the effects of supplementing bioactive peptides derived from rapeseed protein (rapeseed peptide, Rsp) on the growth performance, serum biochemistry and faecal micro‐organism composition of weaned piglets. Sixty Duroc × Landrace × Yorkshire weaned piglets of similar weights were randomly divided into three groups. The control group (NC) was fed a basal diet, and the two treatment groups, Rsp‐1 and Rsp‐2, were fed a basal diet supplemented with 1% or 2% Rsp, respectively, for 28 days. Each treatment consisted of five replicates with four piglets per replicate. The results showed that Rsp treatment significantly improved the average daily gain and had a better feed‐to‐gain ratio (p < 0.05). The diarrhoea incidence and indices of Rsp‐1 and Rsp‐2 groups were significantly lower than the NC group (p < 0.05), and the effect of Rsp‐2 on reducing the incidence of diarrhoea was significantly higher than that of Rsp‐1 (p < 0.05). The serum albumin, serum immunoglobulin A and catalase levels of the Rsp‐1 and Rsp‐2 groups were significantly better than the NC group (p < 0.05). Additionally, Rsp treatment significantly gained the relative abundance of faecal Lactobacillaceae and decreased the relative abundance of faecal Eubacterium_coprostanoligenes_group, Treponema and Coprococcus (p < 0.05). In summary, Rsp supplementation improved the growth performance, ameliorated the diarrhoea, enhanced the immune and antioxidant functions and changed the composition of faecal micro‐organisms in piglets. These findings indicate that Rsp positively affected the health of weaned piglets. [ABSTRACT FROM AUTHOR]

[Objective] This study aimed to increase content of oligosaccharides, obtain enzymolysis products with antibacterial properties, and improve in vitro dry matter digestibility (IVDMD) of corn-soybean feed by screening enzyme patterns and optimizing enzymolysis conditions of non-starch polysaccharide (NSP). [Method] The content of reducing sugar was used as the evaluation index. Five NSP enzymes with different contents (cellulose 110, 220 and 330 U/kg, xylanase 176, 352 and 528 U/kg, pectinase 331, 662 and 993 U/kg, β-glucanase 124, 248 and 372 U/kg, (3-mannase 83, 166 and 249 U/kg) were added into corn-soybean feed to screen optimum enzyme pattern using Li8 (37) orthogonal design. The effects of temperature (35, 45, 55 and 65 °C) on reducing sugar content, and time (0, 3, 6, 9, 12, 15, 18, 21 and 24 h) on carbohydrate composition, antibacterial effect and IVDMD of feed were studied to obtain optimal enzymatic hydrolysis conditions. The enzymatic hydrolysis feed was prepared according to above optimized conditions. A storage test was carried out at 25 °C to compare antibacterial effects among ordinary feed, enzymatic hydrolysis feed and the feed with antiseptic (0. 05% and 0. 10% mass fraction). [Result] The optimum enzyme combinations were cellulose 110 U/kg, xylanase 528 U/kg, pectinase 993 U/kg, (3-glucanase 372 U/kg and p-mannanase 249 U/kg in corn-soybean feed. The optimum temperature for enzymatic hydrolysis was 55 °C and highest reduction sugar yield (17. 98 mg/g) was obtained. The optimum time was 15 h, at which the oligosaccharide content in enzymatic hydrolysis feed was 78. 65 mg/g and enzymolysis products had the strongest inhibitory effect on Escherichia coli. Furthermore, it also showed inhibitory effects on foodborne pathogenic bacteria such as Bacillus cereus, Salmonella and Lactobacillus plantarum. The IVDMD of feed increased over enzymolysis time and reached almost equilibrium of 54. 25% - 56. 25% at 15 h. Feed storage test showed that no spoilage was found in enzymatic feed and the feed with 0. 10% mildew inhibitor, while ordinary feed and feed with 0. 05% mildew inhibitor appeared rot after 2 days storage under certain conditions. The total bacterial plate counts and coliform counts in enzymatic feed were well below the counts in ordinary feed and feed with mildew inhibitor. Enzymatic feed was ineffective against blue mold. [Conclusion] The NSP enzyme pattern and optimal enzymolysis conditions for corn-soybean feed were obtained. The proper enzymolysis of corn-soybean feed by NSP enzyme can significantly improve IVDMD, content of oligosaccharide, and antibacterial ability. [ABSTRACT FROM AUTHOR]

BACKGROUND Soybean meal (SBM) is the most common protein source used in the poultry and livestock industries. It has high‐quality protein, an excellent amino acid (AA) profile, and positive isoflavone properties. However, the antigen proteins in SBM are unsuitable for young animals. The objective of this study was to identify a Bacillus strain that can degrade soybean antigen proteins, and to evaluate the feasibility of its application in SBM fermentation. RESULTS: Bacillus velezensis DP‐2 was isolated from Douchi, a fermented Chinese food. It degraded 96.14% and 66.51% of glycinin and β‐conglycinin, and increased the trichloroacetic acid‐soluble protein (TCAN) content by 5.46 times in the SBM medium. DP‐2 could secrete alkaline protease and neutral protease, with productivities of 5.85 and 5.99 U mL−1. It had broad‐spectrum, antibacterial activities against Rhizopus nigricans HR, Fusarium oxysporum ACCC37404, Penicillium digitatum SQ2, Aspergillus flavus C1, Aspergillus niger ACCC30005, Trichoderma viride YZ1, Candida tropicalis CICC1630, and Salmonella sp. ZY. For SBM fermentation, the optimal inoculum rate, temperature, and fermentation time of DP‐2 were 2.21 × 107 CFU g−1, 37 °C, and 48 h, respectively. The fermented soybean meal (FSBM) was cream‐colored and glutinous. Its crude protein (CP), soluble protein, and TCA‐N content were improved by 13.45%, 12.53%, and 6.37 times, respectively. The glycinin and β‐conglycinin content were reduced by 78.00% and 43.07%, respectively, compared with raw SBM. CONCLUSIONS: Bacillus velezensis DP‐2 has potential as a starter culture for SBM fermentation. © 2020 Society of Chemical Industry [ABSTRACT FROM AUTHOR]