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为了提高棕榈酸对硝基苯酯（p-NPP）法测定脂肪酶活力的灵敏度和准确度，以来源于Rhizopus oryzae的脂肪酶Lipase F-AP 15为研究对象，首先对其最适反应pH和反应温度进行优化，然后将表面活性剂作为激活因子引入酶活力测定体系，探究影响机制，并依据酶反应动力学理论优化测定条件(底物浓度、酶质量浓度、反应时间），对优化的p-NPP法的重复性和准确性进行了检验，最后以另一个来源的脂肪酶Lipase-PPL为模型，以同样思路与方法改进与优化其酶活力测定体系，以考察优化方法和思路的适用性。结果表明：表面活性剂PEG 8000的引入使得覆盖在脂肪酶活性位点的α-螺旋结构被重排而打开，脂肪酶由封闭构象转为并保持在活化构象，脂肪酶活性增强；优化测定体系的最适条件为pH 8.0、反应温度30 ℃、酶质量浓度1.00 mg/mL、底物浓度6 mmol/L、反应时间5 min，在此条件下测得的酶活力是常用p-NPP法（pH 8.0、反应温度30 ℃、酶质量浓度2.50 mg/mL、底物浓度10 mmol/L、反应时间8 min）测得酶活力的1.4倍；重复性和准确性试验显示，优化p-NPP法重复测定结果的相对标准偏差为1.21%,加标回收率为95.60%，均优于常用p-NPP法；优化方法和思路适用于其他来源的脂肪酶活力测定体系的优化。综上，通过将表面活性剂引入p-NPP法的脂肪酶活力测定体系，以酶反应动力学理论为指导优化测定条件，明显提高了方法的灵敏度，并有效保证了测定结果的重复性和准确性，缩短了检测时间，节省了检测成本。 In order to improve the sensitivity and accuracy of p-nitrophenol palmitate (p-NPP) method for the assay of lipase activity, the Lipase F-AP 15 from Rhizopus oryzae was taken as the research object, and the optimum reaction pH and reaction temperature were firstly optimized, then surfactant was introduced into the enzyme activity assay system as an activating factor, and the influence mechanism was explored. The assay conditions (substrate concentration, enzyme mass concentration, reaction time) were optimized according to the theory of enzyme reaction kinetics. The repeatability and accuracy of the optimized p-NPP method were examined. Finally, Lipase-PPL, another source of lipase, was used as a model to improve and optimize its enzyme activity assay system with the same idea and method to examine the applicability of the optimization method and idea. The results showed that with the introduction of surfactant PEG 8000, the α-helix structure covering the active site of lipase was rearranged and opened, and the lipase changed from closed conformation to and remained in the active conformation. The optimum conditions of the assay system were as follows: pH 8.0, reaction temperature 30 ℃, enzyme mass concentration 1.00 mg/mL, substrate concentration 6 mmol/L, and reaction time 5 min. Under the optimized conditions, the enzyme activity measured was 1.4 times that of the common p-NPP method (pH 8.0, reaction temperature 30 ℃, enzyme mass concentration 2.50 mg/mL, substrate concentration 10 mmol/L, and reaction time 8 min). The repeatability and accuracy experiments of the optimized p-NPP method showed that the relative standard deviation of the repeated assay results was 1.21%, and the recovery rate of standard addition was 95.60%, which was better than that of the common p-NPP method. The optimization method and idea was applicable to the optimization of lipase activity assay system from other sources. In conclusion, the introduction of surfactant in the lipase activity assay system of p-NPP method and the optimization of the assay conditions under the guidance of enzyme reaction kinetics theory can significantly improve the sensitivity of the method, effectively ensure the repeatability and accuracy of the assay results, shorten the assay time, and save the assay cost.

光纤通信系统和网络是支撑信息社会的重要基础设施。大数据时代云计算、移动互连和虚拟现实等新型业务的迅速发展对信息传送能力提出了日益增长的迫切需求。为了应对这种需求,光纤传输技术向着更高速率和更大容量不断发展。文章介绍了高速光纤传输近年来的主要技术进展,讨论了面向长距离的相干检测和面向中短距离的直接检测光纤传输使能技术,总结了高波特率光纤传输技术的最新发展与未来趋势。

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[Significance]　The beef cattle industry plays a pivotal role in the development of China's agricultural economy and the enhancement of people's dietary structure. However, there exists a substantial disparity in feeding management practices and economic efficiency of beef cattle industry compared to developed countries. While the beef cattle industry in China is progressing towards intensive, modern, and large-scale development, it encounters challenges such as labor shortage and rising labor costs that seriously affect its healthy development. The determination of animal physiological indicators plays an important role in monitoring animal welfare and health status. Therefore, leveraging data collected from various sensors as well as technologies like machine learning, data mining, and modeling analysis enables automatic acquisition of meaningful information on beef cattle physiological indicators for intelligent management of beef cattle. In this paper, the intelligent monitoring technology of physiological indicators in beef cattle breeding process and its application value are systematically summarized, and the existing challenges and future prospects of intelligent beef cattle breeding process in China are prospected. [Progress]　The methods of obtaining information on beef cattle physiological indicators include contact sensors worn on the body and non-contact sensors based on various image acquisitions. Monitoring the exercise behavior of beef cattle plays a crucial role in disease prevention, reproduction monitoring, and status assessment. The three-axis accelerometer sensor, which tracks the amount of time that beef cattle spend on lying, walking, and standing, is a widely used technique for tracking the movement behavior of beef cattle. Through machine vision analysis, individual recognition of beef cattle and identification of standing, lying down, and straddling movements can also be achieved, with the characteristics of non-contact, stress-free, low cost, and generating high data volume. Body temperature in beef cattle is associated with estrus, calving, and overall health. Sensors for monitoring body temperature include rumen temperature sensors and rectal temperature sensors, but there are issues with their inconvenience. Infrared temperature measurement technology can be utilized to detect beef cattle with abnormal temperatures by monitoring eye and ear root temperatures, although the accuracy of the results may be influenced by environmental temperature and monitoring distance, necessitating calibration. Heart rate and respiratory rate in beef cattle are linked to animal diseases, stress, and pest attacks. Monitoring heart rate can be accomplished through photoelectric volume pulse wave measurement and monitoring changes in arterial blood flow using infrared emitters and receivers. Respiratory rate monitoring can be achieved by identifying different nostril temperatures during inhalation and exhalation using thermal infrared imaging technology. The ruminating behavior of beef cattle is associated with health and feed nutrition. Currently, the primary tools used to detect rumination behavior are pressure sensors and three-axis accelerometer sensors positioned at various head positions. Rumen acidosis is a major disease in the rapid fattening process of beef cattle, however, due to limitations in battery life and electrode usage, real-time pH monitoring sensors placed in the rumen are still not widely utilized. Changes in animal physiology, growth, and health can result in alterations in specific components within body fluids. Therefore, monitoring body fluids or surrounding gases through biosensors can be employed to monitor the physiological status of beef cattle. By processing and analyzing the physiological information of beef cattle, indicators such as estrus, calving, feeding, drinking, health conditions, and stress levels can be monitored. This will contribute to the intelligent development of the beef cattle industry and enhance management efficiency. While there has been some progress made in developing technology for monitoring physiological indicators of beef cattle, there are still some challenges that need to be addressed. Contact sensors consume more energy which affects their lifespan. Various sensors are susceptible to environmental interference which affects measurement accuracy. Additionally, due to a wide variety of beef cattle breeds, it is difficult to establish a model database for monitoring physiological indicators under different feeding conditions, breeding stages, and breeds. Furthermore, the installation cost of various intelligent monitoring devices is relatively high, which also limits its utilization coverage. [Conclusion and Prospects]　The application of intelligent monitoring technology for beef cattle physiological indicators is highly significance in enhancing the management level of beef cattle feeding. Intelligent monitoring systems and devices are utilized to acquire physiological behavior data, which are then analyzed using corresponding data models or classified through deep learning techniques to promptly monitor subtle changes in physiological indicators. This enables timely detection of sick, estrus, and calving cattle, facilitating prompt measures by production managers, reducing personnel workload, and improving efficiency. The future development of physiological indicators monitoring technologies in beef cattle primarily focuses on the following three aspects: (1) Enhancing the lifespan of contact sensors by reducing energy consumption, decreasing data transmission frequency, and improving battery life. (2) Integrating and analyzing various monitoring data from multiple perspectives to enhance the accuracy and utility value. (3) Strengthening research on non-contact, high-precision and automated analysis technologies to promote the precise and intelligent development within the beef cattle industry. [ABSTRACT FROM AUTHOR]

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Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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Copyright of Journal of Drainage & Irrigation Machinery Engineering / Paiguan Jixie Gongcheng Xuebao is the property of Editorial Department of Drainage & Irrigation Machinery Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Chinese Journal of Oil Crop Sciences is the property of Oil Crops Research Institute of Chinese Academy of Agricultural Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

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In order to assess the water resources carrying capacity of the Gansu section of the Yellow River Basin, this paper chose a set of 20 evaluation indicators initially, targeting four distinct secondary regions. Through an analytical process involving sensitivity and correlation assessments, seven indicators that exhibited low sensitivity and high correlation were pruned, culminating in a refined set of 13 indicators. These indicators were systematically organized into four sub-systems of water resources, societal factors, economic aspects, and ecological environment. The composite scores were derived by integrating the entropy weight method with the TOPSIS model. Furthermore, a barrier factor diagnosis model was applied to evaluate the water resources carrying capacity across the four secondary regions. The findings reveal spatial variations in carrying capacity, with the area above Longyangxia station demonstrating the highest capacity, followed by the sections from Longyangxia station to Lanzhou and from Lanzhou to Hekouzhen station, and the lowest capacity observed in the section from Longmen to Sanmenxia station. In terms of temporal trends, barring the area above Longyangxia station, a steady rise in carrying capacity is observed in the remaining three regions. Key factors impeding the water resources carrying capacity in the Gansu section of the Yellow River Basin encompass per capita water availability, water production index, per capita water supply, population density, urbanization rate, and the rate of water usage for ecological environments. Strategic planning of water resources distribution, restructuring water consumption patterns, and synchronizing water resources carrying capacity with economic growth are instrumental in enhancing and sustaining the carrying capacity of the Gansu section of the Yellow River Basin. [ABSTRACT FROM AUTHOR]

Aiming at the problem of non-limit active earth pressure of sand during active displacement of rigid retaining wall, the active failure process of sand under rotating about the base (RB) mode, rotating about the top (RT) mode and translation (T) mode was simulated and analyzed by using PFC 2D . The results show that there are differences in the mobilization of internal friction angle and the soil-wall interface friction angle in soil under different displacement modes. During the active displacement of the retaining wall, the soil failure in RB mode starts from the top of the wall and develops to the foot of the wall. Only the area near the back of the wall appears the principal stress deflection in the soil wedge, and the mobilized value of the internal friction angle in the soil wedge can reach the limit value. In RT mode, the soil failure starts from the foot of the wall to the soil surface along the back of the wall and the sliding surface. The deflection angle of the principal stress in the middle and upper part of the soil wedge behind the wall is large, forming a large principal stress arch, which corresponds to the reduction of the mobilized value of the friction angle in this area relative to the initial internal friction angle. In T mode, the soil failure develops from the top of the wall to the foot of the wall along the back of the wall and from the foot of the wall to the surface of the soil along the slip surface. A small principal stress arch appears in the soil wedge behind the wall, and the mobilized value of the internal friction angle increases from the initial internal friction angle, but it does not reach the limit value. [ABSTRACT FROM AUTHOR]

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Objective To investigate the expression changes of histone deacetylase 7（HDAC7） and ubiquitin-specific peptidase 10（USP10） in non-small-cell lung cancer （NSCLC） tissues and their significance. Methods Ninety-eight NSCLC patients underwent tumor resection, with cancer tissues and adjacent tissues preserved during the operation. Immunohistochemistry was used to detect the expression of HDAC7 and USP10 in tissues. Spearman correlation analysis was used to analyze the correlation between HDAC7 and USP10 expression in NSCLC cancer tissues, and to analyze the relationships between HDAC7 and USP10 expression and the clinicopathological parameters of NSCLC patients. Kaplan-Meier survival curve was used to analyze the relationship between HDAC7 and USP10 expression and the prognosis of NSCLC patients, and the COX multivariate proportional hazard model was used to analyze the factors for the prognosis of NSCLC patients. Results The positive rates of HDAC7 in the NSCLC tissues and adjacent tissues were 65. 31% （64/98） and 6. 12% （6/98), respectively （χ2 =74. 756, P<0. 05). The positive rates of USP10 in the NSCLC tissues and adjacent tissues were 63. 27% （62/98） and 8. 16% （8/98), respectively （χ2 =64. 800, P<0. 05). The positive expression rates of HDAC7 and USP10 in cancer tissues with stage III NSCLC, low tumor differentiation, and lymph node metastasis were higher than those with TNM stage Ⅰ–Ⅱ, high and medium differentiation, and no lymph node metastasis （all P<0. 05). The expression of HDAC7 and USP10 in NSCLC cancer tissues showed a significant positive correlation （r=0. 714, P<0. 05). The 3-year cumulative survival rates of HDAC7 positive and USP10 positive patients were lower in comparison with those of HDAC7 negative and USP10 negative patients （ χ2 =16. 300, 15. 870, respectively； all P<0. 05). Positive HDAC7 expression, positive USP10 expression, poorly differentiated tumor, lymph node metastasis, and TNM stage III were independent risk factors for the prognosis of NSCLC patients. Conclusion HDAC7 and USP10 are highly expressed in NSCLC tissues, HDAC7 and USP10 may synergistically promote the development and progression of NSCLC, and the prognosis of NSCLC patients with high expression levels of HDAC7 and USP10 is poor. [ABSTRACT FROM AUTHOR]

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