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The thermal denaturation of rice structure and its starch crystalline/amorphous structure was studied by mid-infrared (MIR) spectroscopy and two-dimensional mid-infrared (2D-MIR) spectroscopy. The results indicated that the infrared absorption modes of rice starch included νOH-rice, νasCH2-rice, νsCH2-rice, νamide-Ⅰ-rice, νamide-Ⅱ-rice and νC-O-rice. As the measurement temperature increased (303-393 K), the sensitivity of rice starch crystals/amorphous structures to heat and the order of change were different from those in different origins. Further research on the relevant mechanism shows that there are some differences in heat resistance of different rice starch crystal/amorphous structure, which further affects its taste. The study expanded the scope of research on the thermal denaturation of rice structure and its starch crystals/amorphous structures using MIR spectroscopy and 2D-MIR spectroscopy.

In view of main shortcomings of common conveyor belt used in coal mine, a new type of flame retardant conveyor belt with steel mesh core was developed, and the longitudinal tensile strength, bond strength, surface resistance and flame retardant properties of the conveyor belt were studied. The results showed that the average longitudinal tensile strength of the flame retardant conveyor belt with steel mesh core was 1 214 N/mm, the average adhesive strength of working face of the conveyor belt was 13.5 kN/m, and the average adhesive strength of non-working face was 11.4 kN/m. The average surface resistance of working face of the conveyor belt was 3.3×106 Ω, and the average surface resistance of non-working face was 4.8×106 Ω. The average glowiag time and leach-resitant of the conveyor belt with complete cover were not more than 3.0 s, and the average glowiag time and leach-resistant of the conveyor belt without cover were not more than 5.0 s. The indicators of the developed conveyor belt met the relevant provisions of the current major industry standards.

Abstract Establishing specific reference intervals (RIs) of serum 25-hydroxyvitamin D3 [25(OH)D] for children is essential for improving the accuracy of diagnosis and prognosis monitoring of diseases such as rickets and growth retardation. The study including 6,627 healthy children was conducted to establish specific RIs of 25(OH)D for children in Nanning area of China. The results showed that there were statistically significant differences among age, season, and gender of serum 25(OH)D levels, and the age-specific RIs of serum 25(OH)D were 20.3 ~ 53.6 ng/mL for 0 ~ ≤ 1 year and 18.9 ~ 49.6 ng/mL for 2 ~ ≤ 3 years. The age-, season-specific RIs of serum 25(OH)D for 4 ~ ≤ 6 years in spring–summer and autumn–winter were 15.8 ~ 42.6 ng/mL and 15.2 ~ 37.7 ng/mL, respectively. The age-, gender-specific RIs of serum 25(OH)D for 7 ~ ≤ 18 years for males and females were 12.1 ~ 36.1 ng/mL and 10.8 ~ 35.3 ng/mL, respectively. This study successfully established the RIs of serum 25(OH)D, which may help to improve disease diagnosis and monitoring for children in the Nanning area of China.

Background/purpose: Biofilms formed by Klebsiella pneumoniae on medical devices increase infection risk. Fimbriae and capsule polysaccharides (CPSs) are important factors involved in biofilm formation. KP1_4563 in K. pneumoniae NTUH-K2044, a small protein containing the DUF1471 domain, was reported to inhibit type 3 fimbriae function. In this study, we aimed to determine whether the KP1_4563 homolog is conserved in each K. pneumoniae isolate and what role it has in Klebsiella biofilms. Methods: The genomes of K. pneumoniae NTUH-K2044, CG43, MGH78578, KPPR1 and STU1 were compared. The KP1_4563 homolog in K. pneumoniae STU1 was named orfX. Biofilms of wild-type and orfX mutant strains from K. pneumoniae STU1 and one clinical isolate, 83535, were quantified. Transcription levels of the type 3 fimbrial genes, mrkA and mrkH, were investigated by RT-qPCR. MrkA of the wild-type and orfX mutant were observed by Western blotting. The morphology of bacterial cells was observed by transmission electron microscopy (TEM). Bacterial CPSs were quantified. Results: The gene and upstream region of orfX were conserved among the five K. pneumoniae isolates. Deletion of orfX enhanced Klebsiella biofilm formation. However, the amount of mRNA from mrkA and mrkH and the level of MrkA protein were not different between the wild type and orfX mutant. In contrast, the amount of CPS in orfX mutants was increased, compared to their parental strains, STU1 and 83535. Conclusion: The role of orfX is speculated to be conserved in most K. pneumoniae isolates. OrfX negatively controlled biofilm formation by reducing CPS, not type 3 fimbriae, production.

Establishing an accurate predictive model for response parameters is the foundation of control parameter optimization for tunnel boring machines (TBMs). However, existing research mostly focuses on mean values during stable stages, and lacks real-time prediction throughout the entire process, failing to meet the demand for fine-tuned parameter recommendations. This paper proposes the weight matrix method for feature selection, which provides specific numerical values and rankings of each feature's contribution. A deep learning model based on temporal convolutional network (TCN) is proposed to achieve real-time prediction of cutterhead torque (T) and total thrust (F), which is compared with the gated recurrent unit (GRU) and long short-term memory (LSTM). The proposed method was validated on the Yinchao project, and the results demonstrated that (1) the weight matrix method outperforms the Pearson coefficient method in terms of model accuracy, and (2) the TCN model performs better than GRU and LSTM. The method proposed in this paper achieves high precision in predicting T and F , and holds promise as a core algorithm for automatic control in TBM and providing crucial support for TBM's advancement into the era of autonomous driving. [ABSTRACT FROM AUTHOR]

The causes and protective measures of cavitation erosion were summarized. The cavitation corrosion resistance of different kinds of metal coatings prepared by thermal spraying, surfacing, electroless plating and plasma surface technology was introduced. Then, the research progress of organic coating such as epoxy resin series, polyurethane series, ultra high molecular-weight polyethylene coatings in the field of cavitation resistance was reviewed emphatically and compared with metal coatings. The anti-cavitation effect of ceramic organic composite coatings was reviewed. The advantages and disadvantages of several kinds of coatings were compared. Finally, the future research direction was prospected.

The structures of five kinds of millet from Shandong,Shanxi,Hebei and other provinces were studied by mid infrared (abbreviation:MIR) spectroscopy.The results showed that the infrared absorption modes of millet mainly include OH stretching vibration mode (νOH),CH3 asymmetrical stretching vibration mode (νasCH3),CH2 asymmetrical stretching vibration mode (νasCH2),CH2 symmetrical stretching vibration mode (νsCH2),CH stretching vibration mode (νCH),C==O stretching vibration mode (νC==O),protein amide Ⅰband mode (νamide-Ⅰ),protein amide Ⅱ band mode (νamide-Ⅱ),protein amide Ⅲ band mode (νamide-Ⅲ) and C—O stretching vibration mode (νC—O).Furthermore,the corresponding synchronous 2D-MIR spectroscopy of millet,including νasCH3-2d,νasCH2-2d,νsCH2-2d and νCH-2d,have some differences,which can quickly and accurately identify the five kinds of millets.This paper expanded the research scope of three-step MIR spectroscopy in structure and rapid identification of high-quality millet.

Hyaluronic acid (HA), a main component of the extracellular matrix, is widely utilized to deliver anticancer drugs due to its biocompatibility, biodegradability, non-toxicity, non-immunogenicity and numerous modification sites, such as carboxyl and hydroxyl groups. Moreover, HA serves as a natural ligand for tumor-targeted drug delivery systems, as it contains the endocytic HA receptor, CD44, which is overexpressed in many cancer cells. Therefore, HA-based nanocarriers have been developed to improve drug delivery efficiency and distinguish between healthy and cancerous tissues, resulting in reduced residual toxicity and off-target accumulation. This article comprehensively reviews the fabrication of anticancer drug nanocarriers based on HA in the context of prodrugs, organic carrier materials (micelles, liposomes, nanoparticles, microbubbles and hydrogels) and inorganic composite nanocarriers (gold nanoparticles, quantum dots, carbon nanotubes and silicon dioxide). Additionally, the progress achieved in the design and optimization of these nanocarriers and their effects on cancer therapy are discussed. Finally, the review provides a summary of the perspectives, the lessons learned so far and the outlook towards further developments in this field. [ABSTRACT FROM AUTHOR]

Polyhydroxybutyrate (PHB) is one of the polyhydroxyalkanoates (PHAs) which has biodegradable and biocompatible properties. They are adopted in the biomedical field, in, for example, medical implants and drug delivery carriers. This study seeks to promote the production of PHB by Vibrio sp. BM-1, isolated from a marine environment by improving constituents of medium and implementing an appropriate fermentation strategy. This study successfully developed a glycerol-yeast extract-tryptone (GYT) medium that can facilitate the growth of Vibrio sp. BM-1 and lead to the production of 1.4 g/L PHB at 20 h cultivation. This study also shows that 1.57 g/L PHB concentration and 16% PHB content were achieved, respectively, when Vibrio sp. BM-1 was cultivated with MS-GYT medium (mineral salts-supplemented GYT medium) for 12 h. Both cell dry weight (CDW) and residual CDW remained constant at around 8.2 g/L and 8.0 g/L after the 12 h of cultivation, until the end of the experiment. However, both 16% of PHB content and 1.57 g/L of PHB production decreased rapidly to 3% and 0.25 g/L, respectively from 12 h of cultivation to 40 h of cultivation. The results suggest that the secretion of PHB depolymerase that might be caused by the addition of mineral salts reduced PHB after 12 h of cultivation. However, work will be done to explain the effect of adding mineral salts on the production of PHB by Vibrio sp. BM-1 in the near future.