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For multi-platform bearings-only cross location and tracking problem in distributed multi-function sensors, a target tracking management method based on asynchronous bearing only is proposed. The distributed multi-function system requires only one integrated sensor to switch to electronic support measure (ESM) mode within each tracking cycle to update the angle measurement information of target radiation source, while the other integrated sensors still work in the original planned mode and task. Compared with traditional cross location tracking method, the proposed asynchronous bearing only tracking method can improve the capability of the distributed integrated system with multiple functions such as reconnaissance, jamming and active detection at the same time in order to cope with the complex combat environment.

The combination method of numerical simulation and experimental verification was used to optimize the current evaluation method of tear strength of rubber unnicked angle test piece. Firstly, the tear energy at angle position of rubber test piece with different clamp distances was simulated by the simulation software, and then advanced video extensometer-digital image correlation analysis software was used to obtain the strain distribution cloud nephograms and the multi-location strain curves of the test piece with time. A new method was proposed to evaluate comprehensively the unnicked angle tear property by combining strain distribution cloud nephogram and corrected tear strength, and the method applicability was verified by the tear strength test of pure natural rubber and natural rubber/synthetic rubber blends. The results showed that the tensile degree of the non-effective test region and the tear energy at angle position were all different with the different clamp distances, when the other para-meters of the test piece were the same, which increased the volatility of the test results. Compared with the standard currently in effect, the variation coefficient of parallel test results could be reduced by using the corrected tear strength, and the test results was positively correlated with the carbon black dispersion in the vulcanizates.

The accelerator-based boron neutron capture therapy (AB-BNCT) facility is a cancer treatment assembly based on epithermal neutrons generated by an accelerator, which can be built in hospitals in densely populated cities. BNCT has strict requirements for the neutron fluence rate and various contaminations. In order to meet these requirements, the neutron beam shaping assembly (BSA) needs to be designed. The traditional design method for BSA needs to know the performance of various materials in advance in terms of moderation, alignment, shielding, etc. Many researchers have done a lot of work in this area, but the neutron energy changes due to complex nuclear reactions between neutrons and materials. Since the nuclear reaction cross section is closely related to energy, the judgments on the properties of these materials are mostly qualitative and has only little use for the design of BSA. The traditional method first gives a preliminary plan, and then adjusts the material type and material size according to the theoretical calculation results, it is easy to fall into the local optimum, and it is difficult to obtain the global optimal solution. This process takes a lot of time. Traditional design methods rely heavily on the designer’s experience, which is not a good guide for design work. Genetic algorithm is a random global search and optimization method developed by imitating the biological evolution mechanism. It draws on some ideas in evolutionary biology such as heredity, mutation, natural selection and hybridization, and is a general algorithm for solving search problems. The algorithm has little requirements for the problem to be solved, and only needs the fitness function. The genetic algorithm can deal with multiple individuals in the group at the same time, perform parallel search according to multiple routes, and use the roulette method to make selections. The advantage of genetic algorithm is that the search range is large, which is conducive to global selection. Genetic algorithm also has the characteristics of robustness, parallelism and portability. Genetic algorithm has applications in nuclear power plant fuel management, shielding design and reactor BNCT BSA design.In order to solve the problems existing in traditional methods, based on the 14 MeV cyclotron, an optimal design method of BSA based on genetic algorithm was studied in this paper. The program mainly included genetic algorithm module, fitness calculation module, input file generation module and output file processing module. The results show that the method can realize the multi-objective optimization design and obtain good results efficiently. The program can be modified for design in other related fields of nuclear engineering.

Background Cognitive impairment (CI) is highly prevalent in patients with end-stage renal disease (ESRD) , which seriously affects the prognosis of patients. Early identification of its associated factors is of great significance, but there is no agreement as to existing relevant research conclusions, and no relevant systematic reviews conducted with Chinese patients with ESRD. Objective To systematically evaluate the factors associated with CI in Chinese patients with ESRD. Methods Databases of PubMed, Web of Science, EMBase, CNKI, WanFangData, CQVIP and CBM were searched from inception to October 2021 for studies (including cross-sectional studies, cohort studies and case-control studies) about associated factors of CI in Chinese ESRD patients (with stage CKD5 defined in the 2002 Kidney Disease Outcomes Quality Initiative, or treatment with peritoneal dialysis or hemodialysis) using subject words in combination with free words as search terms with adjustment by the database feature when necessary. Two researchers independently performed literature screening, data extraction, and methodological quality assessment. Stata 15.0 was employed for Meta-analysis. Results In total, 44 studies were included, including 42 172 patients, among which, the cohort studies and case-control studies were rated as high-quality evidence, and the cross-sectional studies as moderate or high-quality evidence. Meta-analysis revealed that older age〔OR=1.17, 95%CI (1.13, 1.22) , P

The experiment was conducted to investigate the effects of yellow-corn straw feed treated with calcium propionate on growth performance, digestion and metabolism and serum biochemical indexes of Hu sheep. A total of 30 male Hu sheep with similar age and body weight (21.39 ±0.76) kg were selected and randomly divided into three groups, with 10 replicates per group and one Hu sheep per replicate. The corn straw group (CK group) was fed a basal diet, the yellow-corn straw group (Group A) replaced an equivalent amount of corn straw in the basal diet with yellow-corn straw, and the calcium propionate group (Group B) replaced an equivalent amount of corn straw in the basal diet with yellow-corn straw treated with 0.2% calcium propionate. The trial period was 42 days. The results showed that the average daily weight gain of Hu sheep in Group B was significantly higher than that in the CK group (P<0.05), and the ratio of feed to gain was significantly lower than that in CK group and Group A (P<0.05). The apparent crude protein (CP) digestibility of Hu sheep in Group B was significantly higher than that in CK group and Group A (P<0.05). There were no significant differences in nitrogen metabolism, calcium metabolism, and phosphorus metabolism of Hu sheep among all groups (P>0.05), the nitrogen retention rates and calcium retention rates in Group B were higher than those in CK group and Group A (P>0.05). There were no significant differences in serum biochemical indexes of Hu sheep among all groups (P>0.05), the serum BUN content in Group B tended to decrease compared to CK group and Group A. The study indicates that the addition of yellow-corn straw treated with calcium propionate to the diet can improve the average daily weight gain, reduce the feed to gain ratio, and enhance the apparent digestibility of crude protein in Hu sheep. [ABSTRACT FROM AUTHOR]

To study the regularity of blasting vibration of semi coal and rock roadway and its influence on the broken rock zone, the semi coal and rock roadway of Xinyi Coal Mine is taken as the test site, and the field test of blasting vibration and broken rock zone is carried out. The monitoring data analysis of blasting vibration shows that the main vibration frequency of excavation blasting in semi coal and rock roadway is 50 Hz to 250 Hz, and the main frequency of blasting vibration is higher when the detonating charge of the same section of detonator tube is large. The measured blasting vibration velocity is higher than the theoretical value, and the blasting vibration attenuation formula is fitted by using Sadov’s formula regression, then the permissible safe distance of blasting in different rock layers is calculated. The analysis of the test data of the broken rock zone shows that the range of the broken rock zone of sandstone layer surrounding rock is 1 m to 1.25 m, and the range of coal seam surrounding rock is 1.25 m to 1.5 m. The blasting vibration has little disturbance to the surrounding rock of sandstone layer, and the broken rock zone of coal seam increases by about 0.2 m. With the increase of free surface, the propagation of total explosion energy in rock mass decreases, and the disturbance to surrounding rock by blasting vibration becomes smaller. Based on the results of monitoring and analysis, the improvement measures of charging structure and supporting parameters are put forward.

In order to investigate the relationship between root characteristics and starch properties of rice at grain filling stage in the lower reaches of the Yangtze River under different integrative cultivation practices techniques, field experiments were carried out with Yongyou 2640, Wuyunjing 24, Yangdao 6, and Jinxiangyu 1 as the experimental materials. Five cultivation techniques were set up, including nitrogen blank area (0N), local farmers' practice (control), densification and nitrogen reduction, alternate wetting and drying irrigation and increasing application of rapeseed cake fertilizer. The results showed that compared with the local farmers' practice (control), the yield of Yongyou 2640 under the treatment of densification and nitrogen reduction, alternate wetting and drying irrigation and increasing application of rapeseed cake fertilizer increased by 6.49%, 11.06%, and 12.72%, respectively. The yield of Wuyunjing 24 increased by 1.92%, 11.10%, and 17.05%, respectively. The yield of Yangdao 6 increased by 9.30%, 18.50%, and 22.89%, respectively, and the yield of Jinxiangyu1 increased by 6.92%, 14.72%, and 17.89%, respectively. At the same time, we also observed that with the integration and optimization of cultivation practices, root morphological and physiological characteristics (root dry weight, root length, root diameter, root oxidation activity, root bleeding intensity, zeatin and zeatin riboside contents in root and root bleeding sap and total organic acid content in exudates), the activity of key enzymes for starch synthesis in grains (soluble starch synthase, granule-bound starch synthase), peak viscosity, hot viscosity, breakdown, final viscosity, solubility and swelling degree gradually increased. Correlation analysis showed that the morphological and physiological characteristics of roots at grain filling stage were closely related to grain yield and starch properties. It indicated that the integration and optimization of cultivation practices might improve rice quality through regulating the growth of underground roots, and finally achieve the goals of high yield, good quality and high efficiency. [ABSTRACT FROM AUTHOR]

The spikelet number per panicle is a key factor that constitutes the grain yield in rice. Modern high-yielding rice varieties mostly show high spikelet number per panicle. Increasing the spikelet number per panicle and promoting the formation of large panicles are important ways to improve rice yield. This paper reviewed the relationship between the formation of spikelet number per panicle and young panicle development in rice. Combined with the author's related research, the mechanisms underlying genetic regulation in rice panicle size, the effects of nutritional status and nitrogen fertilizer management, water, temperature, light, and endogenous hormones on the formation of spikelet number per panicle in rice were reviewed. We put forward the future research focus on strengthening the formation of large panicles in rice from the aspects of root morphophysiology and young panicle development, water and nitrogen management, temperature and light conditions, and the physiological and molecular mechanisms of interaction between plant hormones regulating spikelet degeneration. The purpose of this study was to provide a basis for the selection and cultivation of high-yielding rice varieties with large panicles. [ABSTRACT FROM AUTHOR]

The application of panicle nitrogen fertilizer is an important management measure to increase rice yield, but its effect and mechanism of application rates on the yield increase of super rice varieties with different panicle sizes are still unclear. In this study, three super rice varieties with large differences in panicle sizes (indicated by the spikelet number per panicle) of Nanjing 9108 (small panicle size), Yangliangyou 6 (medium panicle size), and Yongyou 1540 (large panicle size) were selected as materials. Under the condition of the same amount of base-tiller fertilizer (162 kg N hm-2), the effects of five panicle nitrogen fertilizer rates (PNR) of 0, 54, 108, 162, and 216 kg hm-2 on the yield of the above rice varieties were studied. And its regulatory effects on the differentiation and degeneration of spikelets and related morphophysiological indices after heading were observed. The results were as follows: (1) In the PNR range of 0-216 kg hm-2, the spikelet number per panicle gradually increased but the seed-setting rate and 1000-grain weight gradually decreased with the increase of PNR. And the higher the PNR, the more obvious the decrease of seed-setting rate and 1000-grain weight. Three rice varieties, Nanjing 9108, Yangliangyou 6, and Yongyou 1540, had the highest yields in the PNR of 162-216, 108-162, and 54-108 kg hm-2, respectively. According to the curve equation of grain yield and PNR, the optimal PNR for high yields of the above three varieties were calculated to be 177.6-182.0, 134.3-136.3, and 109.9-125.7 kg hm-2, respectively. (2) In general, rice varieties with large panicle sizes had higher yields, while rice varieties with small panicle sizes had greater yield-increasing effects of PNR. The number of differentiated and surviving secondary spikelets in rice varieties with small panicle size increased greatly after application of panicle nitrogen fertilizer, which was the main reason that the yield-increasing effect was higher than that of rice varieties with medium and large panicle size. (3) Under the condition of high-yield PNR, high effective leaf area ratio, grain-leaf ratio (spikelet/leaf area, filled grain/leaf area, and grain weight/leaf area), non-structural carbohydrate (NSC) translocation amount, sugar-spikelet ratio, root oxidation activity, activity root of spikelet and zeatin (Z) + zeatin riboside (ZR) content in grains and roots from 0-40 day(s) after heading of three rice varieties were high. Correlation analysis showed that the yields of super rice varieties with different panicle sizes and the above indicators basically had a significant or extremely significant positive correlation. These results indicated that the PNR should be adjusted according to the panicle size. The appropriate PNR was beneficial to maintain a high effective leaf area ratio, grain-leaf ratio, NSC translocation amount, sugar-spikelet ratio, root oxidation activity, activity root of spikelet, and Z + ZR content in grains and roots after heading under the premise of higher total spikelets. This helped to maintain a high seed-setting rate and grain weight, thereby ultimately increasing the grain yield. [ABSTRACT FROM AUTHOR]