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Age gelation is undesirable for direct UHT (dUHT) milk, which is closely related to protein hydrolysis. However, little information is available for the role of serum peptides during the age gelation. In this study, the composition and protein morphology of serum phase were characterized by RP-HPLC, ICP-MS and TEM. The results showed significant increases in soluble proteins, free amino acids, calcium, and phosphorus from casein micelles, indicating protein hydrolysis and peptide release into the serum phase. 23,466 peptides derived from caseins and other proteins were identified in serum phase by peptidomics. The serum peptide profiles of age gelation milk changed dramatically. Peptide fingerprinting revealed that plasmin and cathepsin contributed to the protein hydrolysis during age gelation, with a significant increase in their activity observed. 23 characteristic peptides were ultimately selected as potential indicators for age gelation. These findings provide new insights into the age gelation of UHT milk. • Casein micelles released numerous free caseins and peptides during age gelation. • The significantly increased peptides were mainly derived from β-, αs1- and αs2-casein. • Hydrolysis by plasmin and cathepsin leads to age gelation of dUHT milk. [ABSTRACT FROM AUTHOR]

Varicocele (VC) refers to expansion and tortuosity of spreading venous plexus in spermatic cord due to poor blood flow. This study aimed to investigate effects of Shugan Tongluo Qiangjing recipe (SGTL) on sperm DNA damage and oxidative stress in experimental VC (EVC) rats. EVC model was established by partial ligation of left renal vein. Spermatic vein diameter, testicular weight, sperm DNA fragmentation index (DFI) were evaluated. Telomere reverse transcriptase (TERT) expression, telomere gene transcription, and testicular tissue morphology were determined·H 2 O 2 , catalase, SOD, T-AOC were measured with colorimetry. SGTL significantly decreased spermatic vein diameter (P =0.000) and increased testicular weight (P =0.013) of rats compared those of EVC rats. SGTL maintained testicular tissue morphology in EVC rats. SGTL markedly reduced sperm DFI value in sperm of rats compared to EVC rats (P =0.000). SGTL significantly enhanced TERT expression and telomere gene transcription (P =0.028) in testis of rats compared to EVC rats. SGTL reduced H 2 O 2 levels (P=0.001) and promoted CAT activity (P=0.016), SOD activity (P=0.049), and T-AOC activity (P=0.047) of rats, compared to EVC rats. In conclusion, SGTL could reduce pathogenic process of EVC by reducing sperm DNA damage and regulating telomere length in EVC rats, which may be related to oxidative stress regulation. • SGTL decreased spermatic vein diameter, increased testicular weight and reduced sperm DFI of rats. • SGTL enhanced TERT expression, telomere gene transcription and oxidative stress in rat testis. • SGTL reduce pathogenesis of EVC (sperm DNA damage) by inhibiting oxidative stress. [ABSTRACT FROM AUTHOR]

With the extensive application of laser cutting, the proper planning of the cutting path has a significate impact on industrial production, like clothing, metalware, and furniture. This paper proposes heuristic approaches for the two-dimensional cutting path problem, which aims to find the shortest path to cut pieces from the master plate. Two cutting methods, the arc routing method, and the node routing method, are studied based on whether the piece must be cut separately. A two-step heuristic approach is proposed for the arc routing method. A model based on a generalized traveling salesman problem (GTSP) and a variable neighborhood search (VNS) is introduced for the node routing method. The results show that the proposed two-step heuristic quickly finds the optimal or near-optimal solution. CPLEX using the GTSP model can solve small-size instances, while the VNS can find the solution with good quality in a reasonable time for medium-size instances. In addition, the model and approaches are also tested on larger instances with more than 250 pieces and 20,000 nodes. The results show that the proposed heuristics can handle these instances within a reasonable time. • A two-step heuristic is proposed for the arc routing method. • A new model is proposed for the node routing method. • A variable neighborhood search is introduced for the node routing method. • The two-step heuristic quickly finds the optimal or near-optimal solution. [ABSTRACT FROM AUTHOR]

Coumarin is an allelochemical that is widely present in the plant kingdom and has great potential for weed control. However, its mechanisms of action remain largely unknown. This study employed metabolomic and transcriptomic analyses along with evaluations of amino acid profiles and related physiological indicators to investigate how coumarin inhibits the germination and seedling growth of Eleusine indica by modifying metabolic pathways. At 72 h of germination at 50 and 100 mg L−1 coumarin, E. indica had lower levels of soluble sugar and activities of amylases and higher levels of starch, O 2 −, H 2 O 2 , auxin (IAA) and abscisic acid (ABA) compared to the control. Metabolomic analysis demonstrated that coumarin treatments had a significant impact on the pathways associated with amino acid metabolism and transport and aminoacyl-tRNA biosynthesis. Exposure to coumarin induced significant alterations in the levels of 19 amino acids, with a decrease in 15 of them, including Met, Leu and γ-aminobutyric acid (GABA). Additionally, transcriptomic analysis showed that coumarin significantly disrupted several essential biological processes, including protein translation, secondary metabolite synthesis, and hormone signal transduction. The decrease in TCA cycle metabolite (cis-aconitate, 2-oxoglutarate, and malate) contents was associated with the suppression of transcription for related enzymes. Our findings indicate that the inhibition of germination and growth in E. indica by coumarin involves the suppression of starch conversion to sugars, modification of the amino acid profile, interference of hormone signalling and the induction of oxidative stress. The TCA cycle appears to be one of the most essential pathways affected by coumarin. • The mechanisms of coumarin to inhibit seed germination were investigated in Eleusine indica. • Seed germination of Eleusine indica were sensitive to coumarin. • Exposure to coumarin induced significant alteration in the amino acid profile. • The metabolites and genes related to the TCA cycle was dramatically affected by coumarin. [ABSTRACT FROM AUTHOR]

The successful development of photosynthetic organs is the basis of plant growth and community development. To reveal photo-acclimation to high irradiance in tree species during the course of leaf development and plant succession of subtropical forests, photosynthetic efficiency and photoprotective compounds were analyzed in young and mature leaves of three mid-successional tree species ( Castanopsis fissa , Castanopsis chinensis and Schima superba ) and three late-successional tree species ( Machilus chinensis , Cryptocarya chinensis and Cryptocarya concinna ), grown in 100% full sunlight (FL) or 30% of FL (low light, LL). Young leaves of the two species groups exhibited lower chlorophyll (Chl) content, Rubisco content, net photosynthetic rate ( P n ), carboxylation efficiency ( CE ), effective photochemical yield ( Φ PSII ), photorespiratory electron flow ( J O ), but higher dark respiration ( R d ), and ratios of carotenoids/chlorophylls (Car/Chl), anthocyanins/chlorophylls (Anth/Chl), flavonoids/chlorophylls (Flav/Chl), phenols/chlorophylls (Phen/Chl) and total antioxidant capacity/chlorophylls (TAC/Chl) than those of mature leaves, regardless of growth irradiance. Young leaves of both species groups demonstrated a higher flexibility of Anth/Chl, Flav/Chl, Phen/Chl and TAC/Chl in response to different light conditions than mature leaves. Flav/Chl in young leaves of late-successional group was remarkably higher than that of mid-successional group under the same light conditions. There was a negative correlation between antioxidant-dependent photoprotective potential and photosynthetic efficiency in young and mature leaves of the six tree species grown under either FL or LL. Our results explain partial mechanisms that lie behind the replacement of communities in subtropical forests: highly integrated photoprotective potential allows young leaves of shade-tolerant late-successional species to develop smoothly into mature organs under high irradiance. [ABSTRACT FROM AUTHOR]

Direct ultra-high temperature (dUHT) milk is considered as the next generation of liquid milk product because it keeps more nutritional ingredients and better flavor than UHT milk. However, sedimentation and age gelation are urgent problems to develop dUHT milk. The role of whey protein interaction in the destabilization of dUHT milk is rarely reported. In this study, the interaction between α-lactalbumin (α-La) and β-lactoglobulin (β-Lg) was investigated by thermodynamics, spectroscopy and silico approach at 75 °C (preheat), 145 °C (dUHT) and 37 °C (storage). The results showed that α-La could interact with β-Lg via hydrophobicity along with exothermic reaction. During dUHT and storage, the average molecular weight (MW) distribution of α-La/β-Lg complexes increased from 20.3 kDa to 274.4 kDa. The particle size increased from 135.53 ± 5.26 nm to 153.50 ± 3.83 nm and the zeta potential decreased from −27.80 ± 5.90 mV to −7.73 ± 2.65 mV. Fibrous cluster-like protein bridges promoted the formation of α-La/β-Lg aggregates. The interaction mechanism between α-La and β-Lg was explored by molecular docking and dynamics simulations. It was found that heat treatment reduced the binding free energy of α-La and β-Lg and promoted the formation of α-La/β-Lg complexes. Electrostatic and van der Waals were the main energy contributors to the binding. UHT treatment increased the number of hydrogen bonds and weakened the hydrophobic interaction. These findings indicate that the interaction between α-La and β-Lg forms aggregates during heat treatment and storage, which help to optimize process and storage of dUHT milk. [Display omitted] • UHT treatment promoted the binding of α-La and β-Lg. • Electrostatic interactions and van der Waals forces contributed to the binding during UHT treatment and storage. • Fibrous cluster-like protein bridges were found in α-La/β-Lg complexes at ultra-high temperature. [ABSTRACT FROM AUTHOR]