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Glycosidase is an indispensable enzyme in the sugar industry. It is difficult to maintain the stability of natural glycosidase during long-term high-temperature sugar conversion, limiting its application in industrial production. Numerous studies have shown that protein engineering is an important means for enhancing the thermal stability of glycosidase. This article systematically reviews the latest advances in using protein engineering to improve the thermal stability of glycosidase, and dissects the directed evolution, rational design, and semi-rational design strategies used in protein engineering. It also evaluates the effectiveness of these strategies in enhancing the thermal stability of glycosidase and their potential industrial application value, and presents the advantages, limitations and challenges of each strategy. Finally, it suggests that different strategies should be jointly used to improve the thermal stability of glycosidase and gives an outlook on future research directions with a view to promoting the synergistic improvement of the thermal stability and activity of glycosidase.

As means to meet the needs of long-distance energy supply, safe power supply for remote areas facilities, power supply for the surface of the moon and Mars, and deep space and deep-sea exploration, the application of nuclear energy has attracted more and more attention, which has stimulated the development of a series of innovative reactor concepts. Among them, the heat pipe cooled reactor becomes a research hotspot in nuclear energy due to its simple and compact system and higher reliability and safety. The design goal of the heat pipe cooled reactor is to establish sufficient safety margin on the average heat pipe temperature. If a single heat pipe failure occurs, it should be ensured that the heat pipe conditions nearby do not exceed the maximum allowable temperature and power, thereby preventing the heat pipe cascade failure. In this study, the numerical simulation transient analysis of single heat pipe failure accident was carried out using ANSYS Mechanical APDL software. The temperature distribution of the fuel rod under three severe conditions was solved. The maximum temperature of the core center increases by 123.65 K, 124.15 K and 204.05 K respectively, and the maximum reaches 1 352.49 K, and reaches the extreme value at about 95 s, 105 s and 123 s respectively, entering a new steady state. By comparing the maximum temperature of the core center, the maximum working temperature of the heat pipe, the maximum temperature of the substrate and the time required to reach the new steady state under the three conditions, the conclusion that the central failure heat pipe is outside the core is obtained. Under the most severe conditions, the maximum temperature of the substrate is 1 314.16 K, the peak temperature of the core center reaches 1 352.49 K, and the peak operating temperature of the heat pipe is 1 149.84 K, which does not exceed the allowable operating temperature range and the material temperature limit. In addition, under this condition, the maximum peak heat flux of the No. 4 heat pipe reaches 83 709.87 W, and the maximum final heat flux of the No. 2 heat pipe reaches 7 0183.29 W. According to the heat transfer limit range of the heat pipe, it is determined that there is no risk of overall cascade failure. In this paper, a single heat pipe failure transient analysis model of heat pipe cooled reactor was established, and the heat pipe failure simulation test of heat pipe cooled reactor design was completed to evaluate the real transient thermal response to the fault, which lays a solid foundation for the improvement of core safety analysis and overall design.

Objective To evaluate the clinical application value of transforaminal endoscope-guided module in the treatment of lumbar disc herniation by transforaminal endoscopic. Methods Sixty patients with L5 / S1 lumbar disc herniation were randomly divided into the module group and control group， with 30 cases in each group. In the module group， self-designed transforaminal endoscope-guided module was utilized to assist puncture， and conventional manual puncture was adopted to place the working channel in control group. The success rate of one-time puncture， positioning puncture time and intraoperative X-ray fluoroscopy times were compared between two groups， and the incidence of complications was observed. The Visual Analogue Scale （VAS） score and Oswestry Disability Index （ODI） score of the hip and lower limbs at postoperative 3 months were compared between two groups. Postoperative modified Mac Nab score was employed to evaluate clinical efficacy between two groups. Results All patients successfully completed the operation. Compared with the control group， the success rate of one-time puncture was higher， positioning puncture time was shorter and the times of intraoperative X-ray fluoroscopy was less in the module group （all P <0.05）. There was no statistical significance in the incidence of intraoperative complications between two groups （P >0.05）， and no severe postoperative complications were noted in two groups. In two groups， the VAS score and ODI score at postoperative 3 months were less compared with preoperative levels （both P <0.05）， and there was no statistical significance between two groups （both P >0.05），however， the difference of VAS between preoperative and postoperative values was statistically significant（P <0.05）. There was no statistical significance in the excellent rate of modified Mac Nab score between the module （83.3% （25/30））and control groups （80.0% （24/30）， P >0.05）. Conclusions Transforaminal endoscope-guided module is safe and convenient. This module can effectively shorten puncture time， enhance puncture efficiency and minimize iatrogenic injuries， which is worthy of clinical application.

JAZ proteins are involved in the regulation of the jasmonate signaling pathway, which is responsible for various physiological processes, such as defense response, adaptation to abiotic stress, growth, and development in Arabidopsis. The conserved domains of JAZ proteins can serve as binding sites for a broad array of regulatory proteins and the diversity of these protein-protein pairings result in a variety of functional outcomes. Plant growth and defense are two physiological processes that can conflict with each other, resulting in undesirable plant trade-offs. Recent observations have revealed a distinguishing feature of JAZ4; it acts as negative regulator of both plant immunity and growth and development. We suggest that these complex biological processes can be decoupled at the JAZ4 regulatory node, due to prominent expression of JAZ4 in specific tissues and organs. This spatial separation of actions could explain the increased disease resistance and size of the plant root and shoot in the absence of JAZ4. At the tissue level, JAZ4 could play a role in crosstalk between hormones such as ethylene and auxin to control organ differentiation. Deciphering biding of JAZ4 to specific regulators in different tissues and the downstream responses is key to unraveling molecular mechanisms toward developing new crop improvement strategies.

Soil acidification represents a severe threat to tobacco cultivation regions in South China, exacerbating bacterial wilt caused by Ralstonia solanacearum. The comprehension of the underlying mechanisms that facilitate the restoration of rhizosphere microbial communities in “healthy soils” is imperative for ecologically managing tobacco bacterial wilt. This study focuses on acidified tobacco soils that have been subjected to continuous cultivation for 20 years. The experimental treatments included lime (L), biochar (B), and a combination of lime and biochar (L+B), in addition to a control group (CK). Utilizing rhizosphere biology and niche theory, we assessed disease suppression effects, changes in soil properties, and the co-evolution of the rhizosphere bacterial community. Each treatment significantly reduced tobacco bacterial wilt by 16.67% to 20.14% compared to the control group (CK) (p < 0.05) and increased yield by 7.86% to 27.46% (p < 0.05). The biochar treatment (B) proved to be the most effective, followed by the lime-biochar combination (L+B). The key factors controlling wilt were identified through random forest regression analysis as an increase in soil pH and exchangeable bases, along with a decrease in exchangeable acidity. However, lime treatment alone led to an increase in soil bulk density and a decrease in available nutrients, whereas both biochar and lime-biochar treatments significantly improved these parameters (p

[Objective] Rural resettlement areas are the key areas to consolidate the effective connection between poverty alleviation achievements and rural revitalization. Based on the theory of new endogenous development, the analysis of the influencing factors and extension mechanism of the evolution of the agricultural industry chain is of great significance for preventing the return to poverty and promoting rural revitalization in an all-round way. [Methods] Based on the field research data of Tuanjie Village, a typical resettlement area in Ningxia Hui Autonomous Region in 2023, this study used the random forest model to identify the key factors of the evolution of the agricultural industry chain, and further described the extension mechanism of the agricultural industry chain with the help of the actor network theory. [Results] (1) The driving role of village collective organizations, the downstream sales and services of the industrial chain, the planting income of farmers, the age of respondents, the level of education and the proportion of agricultural income had important effects on the evolution of the agricultural industrial chain. (2) The village collective was the key actor in the extension of the agricultural industry chain in Tuanjie Village, and it relied on land, technology, and other resources to recruit, mobilize, and provide feedback to human actors such as the government, farmers’ cooperatives, enterprises, and farmers, and non-human actors such as land, capital, market, and technology, to eliminate objections, forming a relatively stable heterogeneous actor network. (3) In the process of rural industrial development, guided by the reasonable flow and allocation of factors such as people-land-industry-finance between urban and rural areas, the rural economic scale was expanded and the industrial layout was optimized through the fiv drivers of policy guarantee, capacity improvement, service guarantee, capital investment, and product research and development; With agricultural resources as the base of the industrial chain, the extension mechanism of multi-force cooperation and collaboration should be built to realize the orderly extension of the rural agricultural industry chain. [Conclusion] In the process of rural industrial development in resettlement areas, a network of actors with village collective organizations as the core has formed, which provides strong support for the extension of rural agricultural industry chain and promotes the high-quality development of rural industries.

INTRODUCTION: Daytime napping is frequently seen in older adults. The longitudinal relationship between daytime napping and cognitive aging is unknown. METHODS: Using data from 1401 participants of the Rush Memory and Aging Project, we examined the longitudinal change of daytime napping inferred objectively by actigraphy, and the association with incident Alzheimers dementia during up to 14-year follow-up. RESULTS: Older adults tended to nap longer and more frequently with aging, while the progression of Alzheimers dementia accelerates this change by more than doubling the annual increases in nap duration/frequency. Longer and more frequent daytime naps were associated with higher risk of Alzheimers dementia. Interestingly, more excessive (longer or more frequent) daytime napping was correlated with worse cognition a year later, and conversely, worse cognition was correlated with more excessive naps a year later. DISCUSSION: Excessive daytime napping and Alzheimers dementia may possess a bidirectional relationship or share common pathophysiological mechanisms.