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Abstract Generally, when optimizing a rolling stock schedule, the locations of the depots, or places in the network where the composition changes and maintenance occurs, are assumed known. The locations where maintenance is performed naturally influence the quality of any resulting rolling stock schedules. In this paper, the problem of selecting new depot locations and their corresponding capacities is considered. A two-stage mixed integer programming approach for rolling stock scheduling with maintenance requirements is extended to account for depot selection. First, a conventional flow-based model is solved, ignoring maintenance requirements, to obtain a variety of rolling stock schedules with multiple depot locations and capacity options. Then, a maintenance feasible rolling stock schedule can be obtained by solving a series of assignment problems by using the schedules found in the first stage. The proposed methodology is tested on real-life instances, and the numerical experiments of different operational scenarios are discussed.

Spatial scene similarity plays a crucial role in spatial cognition, as it enables us to understand and compare different spatial scenes and their relationships. However, understanding spatial scenes is a complex task. While existing literature has contributed to spatial scene representation learning, these methods primarily focus on comprehending the spatial relationships among objects, often neglecting their semantic features. Furthermore, there is a lack of scene representation learning methods that can seamlessly handle different types of spatial objects (e.g., points, polylines, and polygons) in a scene. Moreover, since expert knowledge is required for the annotation process of spatial scene understanding, publicly available high-quality annotation data has a limited size which usually leads to suboptimal results. To address these issues, we propose a novel multi-scale spatial scene encoding model called SpatialScene2Vec. SpatialScene2Vec utilizes a point location encoder to seamlessly encode the spatial information of different types of spatial objects. A point feature encoder is employed to encode the semantic features of these objects. A spatial scene embedding is generated by integrating the spatial embeddings and feature embeddings of spatial objects within this scene. Furthermore, to address the limited labeled data problem, we propose a self-supervised learning framework to train the SpatialScene2Vec model in which a contrastive loss is used for spatial scene similarity evaluation. In addition, we introduce a novel spatial scene data augmentation method to generate positive scene augmentations by leveraging the unique characteristics of spatial scenes and random sampling points based on the shapes of polyline/polygon objects within the current spatial scenes. We conduct experiments on real-world datasets for spatial scene retrieval tasks, including vector data types of points, polylines, and polygons. Results show that SpatialScene2Vec outperforms well-established encoding methods such as Space2Vec due to the advantages of the integrated multi-scale representations and the proposed spatial scene data augmentation method, with significant improvements and robustness.

Abstract Background In plant water relations research, predawn leaf water potential (Ψpd) is often used as a proxy for soil water potential (Ψsoil), without testing the underlying assumptions that nighttime transpiration is negligible and that enough time has passed for a hydrostatic equilibrium to be established. The goal of this research was to test the assumption Ψpd = Ψsoil for field-grown grapevines. Results A field trial was conducted with 30 different cultivars of wine grapes grown in a single vineyard in arid southeastern Washington, USA, for two years. The Ψpd and the volumetric soil water content (θv) under each sampled plant were measured multiple times during several dry-down cycles. The results show that in wet soil (Ψsoil > − 0.14 MPa or relative extractable water content, θe > 0.36), Ψpd was significantly lower than Ψsoil for all 30 cultivars. Under dry soil conditions (Ψsoil

Abstract Environmental problems caused by plastic pollution in terrestrial systems have received increasing attention, especially the issues related to micro‐ and nanoplastics. Soils are a major receptacle and reservoir of plastics, and accumulated plastics can negatively affect soil health. In this short review, we discuss the current state of knowledge of subsurface transport of micro‐ and nanoplastics in soils. We discuss the fundamental transport mechanisms for micro‐ and nanoplastics and highlight the peculiarities of environmentally relevant micro‐ and nanoplastics. Plastic particles >10 μm are generally filtered out in soil, but smaller plastic particles have the potential to move through soil. Larger plastics in soil will break down into micro‐ and nanoplastics over time due to environmental weathering reactions, making the plastics more prone to subsurface transport. Moreover, interactions with microorganisms and dissolved organic matter may render micro‐ and nanoplastics more hydrophilic, thereby facilitating subsurface transport. Further, soil organisms can move plastic particles by bioturbation, and plastics themselves can affect soil hydraulic properties. Although much of the past research has focused on transport of pristine plastic particles, focus should be given to environmentally relevant plastics, considering the complexities of irregular shape, polydisperse size, and heterogenous surface properties, as well as the temporal changes of these properties caused by continuous environmental modifications.

Plastic mulching is a critical agricultural practice for food production, which provides multiple benefits, including water conservation, weed control, and increased crop yield and quality. However, the application of conventional polyethylene mulch films has led to plastic pollution in the terrestrial environment because mulch residues in fields are difficult to remove and recycle. To address this issue, soil-biodegradable plastic mulch (BDM) films have been introduced to replace conventional polyethylene mulch films, as BDM films are designed to provide desired agronomic outcomes as well as in-situ disposal and degradation. Thus, increasing interests have been expressed toward BDM films in both research and application areas. In this review, we summarize and synthesize current knowledge about BDM films, regarding the history, definition and use, in-field degradation, agronomic performance, environmental impacts, and economic feasibility. In-field research suggests that BDMs show satisfactory agronomical performance but vary considerably in biodegradability among different products and environmental conditions, and generally do not impair soil health. However, laboratory studies indicate that BDMs may negatively impact terrestrial and aquatic ecosystems. Overall, current data indicate that BDMs are a promising alternative of conventional polyethylene mulch films. Questions remain about in-field biodegradation, potential accumulation of BDM residues in soils, release of nonbiodegradable additives, and off-site transport of biodegradable plastic residues (including micro- and nanoplastics) to air and water. We provide recommendations to address these questions and challenges to ensure safe and sustainable use of BDM films in agriculture. [ABSTRACT FROM AUTHOR]

Enterohemorrhagic Escherichia coli (EHEC) serotype O157:H7 is a commonly encountered foodborne pathogen that can cause hemorrhagic enteritis and lead to hemolytic uremic syndrome (HUS) in severe cases. Bifidobacterium is a beneficial bacterium that naturally exists in the human gut and plays a vital role in maintaining a healthy balance in the gut microbiota. This study investigated the protective effects of B. longum K5 in a mouse model of EHEC O157:H7 infection. The results indicated that pretreatment with B. longum K5 mitigated the clinical symptoms of EHEC O157:H7 infection and attenuated the increase in myeloperoxidase (MPO) activity in the colon of the mice. In comparison to the model group, elevated serum D-lactic acid concentrations and diamine oxidase (DAO) levels were prevented in the K5-EHEC group of mice. The reduced mRNA expression of tight junction proteins (ZO-1, Occludin, and Claudin-1) and mucin MUC2, as well as the elevated expression of virulence factors Stx1A and Stx2A, was alleviated in the colon of both the K5-PBS and K5-EHEC groups. Additionally, the increase in the inflammatory cytokine levels of TNF-α and IL-1β was inhibited and the production of IL-4 and IL-10 was promoted in the K5-EHEC group compared with the model group. B. longum K5 significantly prevented the reduction in the abundance and diversity of mouse gut microorganisms induced by EHEC O157:H7 infection, including blocking the decrease in the relative abundance of Roseburia, Lactobacillus, and Oscillibacter. Meanwhile, the intervention with B. longum K5 promoted the production of acetic acid and butyric acid in the gut. This study provides insights into the use of B. longum K5 for developing probiotic formulations to prevent intestinal diseases caused by pathogenic bacterial infections.

Bifidobacterium longum is a common probiotic; both viable and heat-inactivated Bifidobacterium longum have many probiotic effects, such as anticancer effects. But some mechanisms of anticancer effects are still unclear, especially for heat-inactivated probiotics. In this study, we analyzed the effects of viable and heat-inactivated Bifidobacterium longum D42 on human colon cancer cells (HT-29). Cell proliferation, membrane permeability and apoptosis were detected by using the CCK-8 method, LDH method and Annexin V-FITC/PI kits. The ROS level and mitochondrial membrane potential were examined using the fluorescent probes DCFH-DA and JC-1. Real-time fluorescence quantitative PCR (RT-qPCR) and Western blot were used to detect the expression of mitochondrial apoptosis pathway genes and proteins. The results showed that viable and heat-inactivated Bifidobacterium longum D42 at concentrations of 1 × 106 CFU/mL significantly inhibited the proliferation of and increased the level of LDH release of HT-29 colon cancer cells. We found that they could increase the apoptosis rate of HT-29 cells. Moreover, they could also induce apoptosis by inducing cells to produce ROS and destroying the mitochondrial membrane potential of cells. Further studies found that they could increase the mRNA transcription and protein expression levels of the Caspase-3, Caspase-9 and Bax genes in cells, and reduce the mRNA transcription and protein expression levels of the Bcl-2 gene. In summary, our findings revealed that viable and heat-inactivated Bifidobacterium longum D42 have inhibitory effects on proliferation and promote the apoptosis of human colon cancer cells, and also have certain adjuvant drug therapeutic effects and have potential application value in the adjuvant treatment of colon cancer.

Exopolysaccharides (EPS) are biological macromolecules produced by Bifidobacterium to the outside of the cell wall during growth and metabolism. The EPS of Bifidobacterium have anti-inflammatory and antimicrobial activities and could regulate the immune system. In this study, the Bifidobacterium longum subsp. infantis E4 (B. infantis E4) has 21 specific genes for carbohydrate transport and metabolism compared with other 12 strains of B. infantis and could produce exopolysaccharides. The average molecular weights of EPS-1, EPS-2 and EPS-3 were 2.68 × 104, 3.79 × 104 and 4.72 × 104 Da, respectively. The EPS-1 mainly comprised of 7 kinds of monosaccharide, and EPS-2 and EPS-3 mainly comprised of 8 kinds of monosaccharide. The immunomodulatory and anti-inflammatory properties of EPS-1, EPS-2 and EPS-3 on RAW264.7 cells, spleen lymphocytes and NK cells of mouse were investigated in vitro of this study. EPS-1, EPS-2 and EPS-3 promoted the growth and increased phagocytic index of macrophage RAW264.7 at the concentration of 100 μg/mL. Subsequently, EPS-1, EPS-2 and EPS-3 groups were found to increase splenic lymphocyte proliferation and NK cell activity. Compared with the LPS group, EPS-1, EPS-2 and EPS-3 reduced the production of NO, IL-1β, IL-6, TNF-α and PGE-2 in RAW264.7 cells after in lipopolysaccharide (LPS) induced, with EPS-1 having the best effect. Meanwhile, EPS-1, EPS-2 and EPS-3 down-regulated the expression levels of LPS-induced NF-κβ signaling pathway-related genes p-p65, p-Iκβ, iNOS, COX-2 and reduced the nuclear translocation of p65 protein in RAW264.7 cells. In conclusion, our study suggested that EPS produced by B. infantis E4 has immunostimulatory and anti-inflammatory activities and may serve as a potential prebiotic to maintain future health.

Cow milk protein allergy is one of the most common food allergic reactions in early childhood and often persists through adult life. Probiotics have influence on the intestinal microbiota and modulate the immune response. They may be tools that prevent or alleviate certain pathologies involving the gut immune system, such as cow milk protein allergy. In this review, significant research advances on cow milk protein allergy are explored, milk protein allergens and allergy mechanism are introduced. This review highlights recent progress in the probiotics related tothe cow milk protein allergy, which could improve milk protein allergy by regulating intestinal flora and improving intestinal immunity. Finally, the research status of hypoallergenic products is described as well as the problems faced in research and application are put forward. The in-depth study of probiotics to improve milk protein allergy has been a major breakthrough in the field of allergies, providing the theoretical basis for alleviating milk allergy.

ABSTRACT: In recent years, yogurt has been one of the most popular fermented dairy products and is sold worldwide. In this study, pH and titrated acid changes of 4 strains of Lactobacillus delbrueckii ssp. bulgaricus fermented milk during storage were detected. The difference between L. bulgaricus KLDS1.1011 and KLDS1.0207 was significant, with the latter exhibiting reduced acidity levels. Therefore, we determined the complete genome sequence of the 2 strains. Then the expression of specific genes and common genes related to glucose metabolism and proteolysis of L. bulgaricus KLDS1.1011 and KLDS1.0207 were detected by quantitative real-time reverse-transcription PCR. Analysis indicated that the key enzymes in glycometabolism and proteolysis of L. bulgaricus KLDS1.1011 were significantly different than those of L. bulgaricus KLDS1.0207. The contents of lactose and glucose decreased during storage of L. bulgaricus fermented milk, as determined by HPLC, and the contents of lactic acid and galactose increased, with L. bulgaricus KLDS1.1011 increasing less. With skim milk as a raw material, L. bulgaricus KLDS1.1011, KLDS1.0207, and Streptococcus thermophilus S1 were used as fermentation strains to yield yogurt at 42°C, and sensory evaluation was compared with yogurt fermented by commercial starter cultures. Yogurt from L. bulgaricus KLDS1.1011 was the highest-rated. Therefore, the study may provide guidelines for the development of yogurt starters.

In this study, the antioxidant properties of intact cells (IC), cell-free supernatant (CFS), and cell-free extracts (CFE) and whole genome sequencing of Bifidobacterium bifidum E3 (B. bifidum E3), as well as the structural characteristics and antioxidant properties of EPS-1, EPS-2, and EPS-3, were evaluated. The results revealed that intact cells (IC), cell-free supernatant (CFS), and cell-free extracts (CFE) had potent DPPH (1,1-Diphenyl-2-picrylhydrazyl radical), hydroxyl, and superoxide anion radical scavenging capacities, among which CFS was the best. At the genetic level, we identified a strong carbohydrate metabolism capacity, an EPS synthesis gene cluster, and five sugar nucleotides in B. bifidum E3. Therefore, we extracted cEPS from B. bifidum E3 and purified it to obtain EPS-1, EPS-2, and EPS-3. EPS-1, EPS-2, and EPS-3 were heteropolysaccharides with an average molecular weight of 4.15 × 104 Da, 3.67 × 104 Da, and 5.89 × 104 Da, respectively. The EPS-1 and EPS-2 are mainly comprised of mannose and glucose, and the EPS-3 is mainly comprised of rhamnose, mannose, and glucose. The typical characteristic absorption peaks of polysaccharides were shown in Fourier transform infrared spectroscopy (FT-IR spectroscopy). The microstructural study showed a rough surface structure for EPS-1, EPS-2, and EPS-3. Furthermore, EPS-1, EPS-2, and EPS-3 exhibited potent DPPH, hydroxyl, and superoxide anion radical scavenging capacities. Correlation analysis identified that antioxidant capacities may be influenced by various factors, especially molecular weight, chemical compositions, and monosaccharide compositions. In summary, the EPS that was produced by B. bifidum E3 may provide insights into health-promoting benefits in humans.

Excessive immune responses and intestinal barrier injury are leading causes of inflammatory bowel diseases (IBD). Previously, we demonstrated that B. longum subsp. longum K5 alleviated DSS-stimulated colitis in mice, while K15 could not. Here, we investigated both strains' underlying mechanisms regarding their anti-inflammatory and intestinal barrier protective capacities. We assessed the potential characters of two strains, anti-inflammation activities in the LPS-induced RAW 264.7 cell model, and intestinal epithelial barrier functions in the LPS-induced Caco-2 cell monolayers model. Results showed that B. longum subsp. longum K5 exhibited high inhibition against the adhesion of E. coli ATCC 25922 to HT-29 and acetic acid production. B. longum subsp. longum K5 (MOI 1:100) significantly decreased the pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) and inflammatory mediator ROS, NO level in LPS (1 μg/mL) -induced RAW 264.7 cells. It also significantly increased TEER value and decreased paracellular permeability of Caco-2 cells stimulated by LPS. B. longum subsp. longum K5 (MOI 1:100) up-regulated ZO-1, occlaudin and claudin-1 mRNA expression, down-regulated the mRNA expression level of TLR4 and pro-inflammatory cytokines (TNF-α, IL-1β, IL-6) in LPS (100 μg/mL) -stimulated Caco-2 cells. While B. longum subsp. longum K15 did not do as well as B. longum subsp. longum K5 on these assays. Furthermore, the whole-genome sequencing results revealed a gene encoding fatty acid synthase associated with the immune system in K5 specific genes, LacI family related with carbohydrate metabolism, and serine/threonine-protein kinase involved in signal transduction with an amino acid mutation. Our findings provided the theoretical basis for B. longum subsp. longum K5 to be used as a candidate for IBD therapy.

Colon cancer is the most common type of malignant tumor. The cytotoxicity effect of lactic acid bacteria may be active by inhibiting cancer cell proliferation, producing anticancer compounds, and inducing apoptosis in cancer cells, but the mechanism is unclear. Our previous study revealed that Lactobacillus acidophilus KLDS1.0901 has good probiotic properties. In this study, We screened out the highest inhibition rate of L. acidophilus KLDS1.0901 and assessed the effects on the proliferation of HT-29, Caco-2, and IEC-6 cells. Then, the apoptosis mechanism of HT-29 cells was studied when treated with L. acidophilus KLDS1.0901. Results showed that L. acidophilus KLDS1.0901 inhibited the proliferation of HT-29 and Caco-2 cells in a dose-dependent manner and reached the maximum under the condition of multiplicity of infection (MOI) = 100 (rate of Lactobacillus to cells) at 48 h. With the increase in time and MOI, reactive oxygen species in HT-29 cells, the apoptosis rates of HT-29 cells were increased, and the amount of blue fluorescence of the cells was also increased after Hoechst 33258 staining. Furthermore, L. acidophilus KLDS1.0901 reduced the mitochondrial membrane potential of HT-29 cells. Notably, 1,133 differentially expressed genes were screened by transcriptomics research, including 531 up-regulated genes and 602 down-regulated genes. These genes were involved in the nuclear factor κB and PI3K-AKT signaling pathways related to the apoptosis of HT-29 cells. These findings suggested that L. acidophilus KLDS1.0901 has the potential to be used in the development of a new type of functional foods for adjuvant treatment of colon cancer.

Bifidobacterium species are the dominant bacteria in the intestinal tract of infants and young children, and are closely related to intestinal development. The Bifidobacterium longum subsp. longum strains K2-21-4 has been shown to promote the proliferation of CCD841 CoN cells. We evaluate the effect of B. longum on the proliferation of CCD841 CoN cells and tight junction using a lipopolysaccharide (LPS)-induced injury model. We discovered that B. longum K2-21-4 increased the cell proliferation rate and total cell protein content, shortened the cell cycle process, reduced apoptosis, and increased the activity of adenosine triphosphate (ATP)ases, aspartate aminotransferase, and alanine aminotransferase. Real-time reverse transcription quantitative polymerase chain reaction and western blotting showed that B. longum K2-21-4 activated Wnt/β-Catenin and PI3K/Akt/mTOR signaling pathway at gene transcription and protein expression levels up-regulated the expression level of protein related to the tight junction. Our findings suggest that B. longum K2-21-4 could regulate intestinal development by promoting cell proliferation and accelerating the maturation of the internal barrier.

Human milk is closely correlated with infant gut microbiota and is important for infant development. However, most infants receive exclusively insufficient breast milk, and the discordance between effects of commercial formula and human milk exists. To elucidate the differences induced by various feeding methods, we determined microbiota and metabolites composition in fecal samples from 77 healthy infants in Northeast China and identified the differences in various feeding methods. Bacterial 16S rRNA gene sequence analysis demonstrated that the fecal samples of exclusively breastfed (BF) infants were abundant in Bifidobacterium and Lactobacillus; the mixed-fed (MF) infants had the highest abundance of Veillonella and Klebsiella; the exclusively formula-fed (FF) infants were enriched in Bacteroides and Blautia; and the complementary food-fed (CF) infants were associated with higher relative abundance of Lachnoclostridium and Akkermansia. Liquid chromatography–mass spectrometry (LC-MS)-based metabolomics data revealed that the fecal samples of BF infants had the highest abundance of dl-citrulline, threonine, l-proline, l-glutamine, guanine, and l-arginine; the MF infants were abundant in d-maltose, stearidonic acid, capric acid, and myristic acid; the FF infants were enriched in itaconic acid, 4-pyridoxic acid, prostaglandin B2, thymine, dl-α-hydroxybutyric acid, and orotic acid; and the CF infants were associated with higher relative abundance of taurine, l-tyrosine, adenine, and uric acid. Furthermore, compared with the BF infants, the MF and FF infants were more abundant in fatty acid biosynthesis. Collectively, these findings will provide probable explanations for some of the risks and benefits related to infant feeding methods and will support a theoretical basis for the development of infant formula.

Diabetes has become the second most severe disease to human health. Probiotics are important for maintaining gastrointestinal homeostasis and energy balance and have been demonstrated to play a positive role in the prevention and treatment of metabolic syndromes, such as obesity, inflammation, dyslipidemia, and hyperglycemia. The objective of this study was to screen potential antidiabetic strains in vitro and evaluate its effects in vivo. For the in vitro section, dipeptidyl peptidase IV (DPP-IV) inhibitory and antioxidant activities of 14 candidate Lactobacillus spp. strains were tested. Then hydrophobicity and acid and bile salt tolerance assays were determined. The most promising in vitro strain was further evaluated for its antidiabetic properties in vivo using type 2 diabetes mice induced by high-fat diet and intraperitoneal injection of streptozotocin (STZ). The reference strain for this study was Lactobacillus rhamnosus GG. Results showed that cell-free excretory supernatants and cell-free extracts of Lactobacillus acidophilus KLDS1.0901 had better DPP-IV inhibitory activity, antioxidative activities, and biological characteristics than other strains. At the end of the treatment, we found that L. acidophilus KLDS1.0901 administration decreased the levels of fasting blood glucose (FBG), glycosylated hemoglobin, insulin in serum and AUCglucose, and increased the level of glucagon-like peptide 1 in serum compared with diabetic mice (p < 0.05). Moreover, L. acidophilus KLDS1.0901 supplementation increased the activities of superoxide dismutase, glutathione peroxidase, the level of glutathione, and reduced the level of malondialdehyde in serum. These results indicated that L. acidophilus KLDS1.0901 could be used as a potential antidiabetic strain; its application as food supplement and drug ingredient is thus recommended.