Characteristic tryptic peptides and gelling properties of porcine skin gelatin affected by thermal action

Thermal action in extraction process had effects on characteristic tryptic peptides identification and gelling properties of porcine gelatin. SDS-PAGE, HPLC-LTQ/Orbitrap high-resolution mass spectrometry, texture analyser and rheometer were used to evaluate collagen depolymerisation degree, characteristic tryptic peptides and gelling properties of gelatins prepared in various thermal actions. Results showed that with increasing temperature and time, depolymerisation degree enlarged, while gel strength, gelling and melting temperature decreased. Mass spectra showed that 47 and 49 common characteristic tryptic peptides were identified in gelatins extracted at 50 °C and 100 °C with various times, respectively. Moreover, 34 common characteristic tryptic peptides were identified in all gelatin samples. Further comparison between this work and our previous investigations yielded 20 common characteristic tryptic peptides, which stably exist in various thermal actions. These common characteristic tryptic peptides may be very helpful for the accurate authentication of porcine gelatin.     

Sustainable phenolic thermosets coatings derived from urushiol

The over-exploitation of finite fossil resources and/or the increased environmental and sustainable awareness inspire scientists and technologists to search for inexpensive alternatives from renewable chemicals. Phenol formaldehyde (PF) resins, the oldest type of synthetic polymers with good mechanical properties and heat resistance, are widely used in the production of coatings, laminates, molding compositions, and glues. Here, biobased urushiol-derived PF resins were synthesized from the alkali-catalyzed reaction between urushiol and formaldehyde. The chemical compositions and molecular structures of resole resins were characterized by carbon-13 nuclear magnetic resonance and Fourier transform infrared spectroscopy, and their curing behaviors were studied by differential scanning calorimetry. The as-prepared urushiol-derived resole resins had methylol (Ph−CH₂OH), ortho- and para-hemiformal groups (Ph−CH₂OCH₂OH), and the para−para/ortho−para/ortho−ortho links of methylene groups (Ph−CH₂−Ph), whereas the resole resins had low curing temperatures at about 100–113°C. Additionally, given the long side alkyl group moiety on the aromatic rings of urushiol, the films of cured urushiol-derived resole resins had low glass transition temperatures of 132 ± 2°C. Furthermore, the as-prepared urushiol-derived coatings exhibited excellent physical and mechanical properties.     

中国传统饮食文化融入食育路径研究

为国民身体素质、探索具有中国特色的现代食育之路，必须深入分析与探索中国饮食文化中的食育理念。文章以传统饮食文化为出发点和落脚点，概括出医食同源、饮食有节、饮食有礼等先进的食育观点。分析传统饮食与现代食育的关系，认为食育是弘扬传统饮食文化的重要途径，传统饮食文化是发展现代食育的基础。但探索现代食育仍面临着西方快餐文化冲击和国民食育进程缓慢等困境，必须采取强化国民食育意识、加强食育法制建设、健全食育教育体系、推进食育试点工作等措施促进中国传统饮食文化融入食育体系建设，真正探索具有中国特色的食育之路。     

自动化黄酒酿造系统技术的创新和特点

对筒仓贮存和输送、浸米、蒸饭、计量投料、生熟麦曲、压榨、澄清和勾兑、过滤、CIP清洗、煎酒过程等自动化酿造黄酒系统的创新点和特点详细论述,创新无缝连接的自动控制接合技术和集成,使各工序、设备、控制系统之间实现了流水线式连接贯通,建立了黄酒自动化酿造的集成技术,研制成功了自动化黄酒酿造系统,建成年产4万千升自动化黄酒酿造生产线;经生产运行,黄酒自动化酿造生产线运行良好,为酿酒业创新作贡献。     

Olfactory responses of Stegobium paniceum to different Chinese medicinal plant materials and component analysis of volatiles

Stegobium paniceum (L.) (Coleoptera: Anobiidae) is among the major pests of stored products, causing great damage to stored Chinese medicinal plant materials (CMPMs) in China. Effective control strategies are urgently needed. The aim of this study was to explore the role of volatile organic compounds in the host preference of S. paniceum. First, the olfactory behavioral responses of S. paniceum adults to volatiles from four CMPMs (Panax notoginseng, Angelica sinensis, Gastrodia elata, and Peucedanum praeruptorum) were tested in Y-tube olfactometer experiments. Then, the volatile composition of these plant materials were analyzed by gas chromatography-mass spectrometry (GC-MS). S. paniceum showed significant preferences for volatiles from the four CMPMs, compared with clean air (CA). When S. paniceum was presented with choices among different CMPMs, it showed the strongest preference for P. notoginseng, followed by A. sinensis, then G. elata, and P. praeruptorum. GC-MS analysis identified 43, 34, 28 and 60 components in the volatile profiles of P. notoginseng, A. sinensis, G. elata, and P. praeruptorum, respectively. Falcarinol (14.4%), 3-n-butyl phthalide (78.7%), p-cresol (40.1%), and β-pinene (29.1%) were the most abundant components of the volatiles of P. notoginseng, A. sinensis, G. elata, and P. praeruptorum, respectively. The olfactory responses of S. paniceum to the four CMPMs demonstrated that host-related volatiles play an important role in the host-searching process by adult beetles. This information will be useful for the development of safe and effective trapping strategies for this pest.     

Molecular detection and identification of Rickettsia in psocids collected from herbs

The aims of this study were to assess the psocids that potentially carry Rickettsia and to characterize Rickettsia species. We collected booklice from dried fragments of Chinese medicinal herbs for retail. Species identification and Rickettsia detection were performed by using nondestructive DNA extraction method and PCR. Of the 224 booklice samples collected, the following species were identified: Liposcelis pearmani (50.89%), L. bostrychophila (25.89%) and L. entomophila (23.21%). Twenty-four samples were found to be positive for Rickettsia (10.71%, 24/224), and the number of Rickettsia-positive samples per species was as follows: L. pearmani (n = 10), L. bostrychophila (n = 8) and L. entomophila (n = 6). The phylogenetic tree revealed that the rickettsial agents found in booklice cluster along with Rickettsia felis belong to the spotted fever group (SFG). Mixed booklice contamination occurs in herbal fragments. The presence of Rickettsia-infected booklice suggests that there is a risk of louse-borne rickettsioses to humans in contact with herbs. These findings can contribute to the development of a disease control program that assists relevant practitioners and promotes public health.     

中药口服液提取工艺的分析

对中药口服液提取工艺进行了简单的分析讨论。其中,重点对现有的中药口服液提取工艺方法进行了探讨,并由此思考了水提醇沉法的优化改进,仅供参考。     

计算机辅助汉字书写教学技术研究综述

传统的汉字书写教学方法具有一定的局限性，为此人们开始关注计算机辅助的汉字书写教学技术。它主要研究汉字书写规范的智能化、自动化评判方法以及可视化的反馈形式。对近20年来计算机辅助汉字书写教学技术的发展情况进行了综述；详细介绍了数字化展示、书写评判、水平评测等几个研究分支的特点、关键问题以及主要成果；结合相关技术的发展和需求的变化，提出了汉字书写数字化教学技术在未来的发展方向。     

Degradation pattern of contact resistance and characteristic trap energy in blue organic light-emitting diodes

Thin and lightweight organic light-emitting diodes (OLEDs) are promising candidates for next-generation rollable displays; they offer numerous advantages, such as scalable manufacturing, high color contrast ratio, flexibility, and wide viewing angle. Despite the numerous merits of OLEDs, the insufficient lifetime and stability of blue OLEDs remain unresolved, thereby necessitating a feedback strategy for lifetime extension. Herein, we propose a simple yet effective methodology to determine the contact resistance (R_CT) and characteristic trap energy (E_T) of OLEDs simultaneously in the trapped-charge-limited-conduction regime, where electroluminescence occurs primarily. To validate our approach, the extracted R_CT and E_T values are directly compared with each other by connecting a commercial resistor (R_C) to a blue OLED in series. The percent errors discovered in R_C and E_T are less than 7% and 4%, demonstrating the high feasibility and accuracy of our approach. We further employ this method to study the degradation mechanism of a blue OLED by presenting the electrical stress time- and cycle-dependent R_CT, E_T, ideality factor, and turn-on voltage, revealing different degradation patterns of the metal-to-transport layer interface and emission layer, respectively. Our results provide better insights into the electrical parameter extraction method and electrical current degradation mechanism in blue OLEDs.