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A doppler radar holds promising prospects in the field of indoor target localization. However, traditional Doppler radar systems suffer from high power consumption, large size, and noticeable radio frequency interference issues when transmitting carriers of different frequencies. Therefore, an ISABO-based (improved subtraction-average-based optimizer) target localization algorithm for a single-frequency Doppler radar is proposed in this paper. Firstly, a mathematical model for target localization is established according to the spatial geometric relationships during the target movement and the Doppler frequency-shift information in the single-frequency echo signal. Then, the optimization function is constructed with the target motion error as the optimization goal. Finally, an improved subtraction-average-based optimizer algorithm is proposed to solve the optimal parameters and realize the target positioning. The experimental results show that the proposed method can achieve centimeter-level localization accuracy with a cost-effective system structure. [ABSTRACT FROM AUTHOR]

Cupressus gigantea W. C. Cheng & L. K. Fu is an endemic conifer tree species that is distributed widely along the northern portion of the deep gorge of the Yarlung Tsangbo River on the Tibetan Plateau. However, as a key plant species growing on the Tibetan plateau, C. gigantea has since become an endangered species due to habitat loss and degradation, overexploitation, and other factors. It has been listed as a first-grade national protected wild plant species in China. Accordingly, to conserve this plant species, we should obtain more information on its genetic structure. In this study, the genetic diversity and structure among 67 samples were evaluated by the inter-simple sequence repeat (ISSR) technique. Overall, 78 bands were produced with a molecular length of 200 bp to 3100 bp using 10 ISSR primers. The mean values for the average number of alleles (Na), effective number of alleles (Ne), Nei's gene diversity (H), and Shannon's information index (I) were 1.529, 1.348, 0.199, and 0.293, respectively. Additionally, the number of polymorphic loci (NPLs) and percentage of polymorphic loci (PPLs) averaged 41.25 and 52.90, respectively. Further, total variation among populations was 14.2%, while that within populations was 85.8%; accordingly, the within-population genetic differentiation was found to be significant (p < 0.001). These results demonstrated that a genetic structure model with K = 3 fitted the data best, which agreed with the unweighted pair group method with arithmetic average (UPGMA) cluster and the principal coordinate analysis (PCoA). These findings are beneficial for ensuring the development and genetic protection of C. gigantea populations in the future. [ABSTRACT FROM AUTHOR]

Bleeding is as particularly a serious phenomenon in Actinidia arguta and has important effects on this plant's growth and development. Here we used A. arguta to study the effects of bleeding on the growth and development of leaves and fruits after a bleeding episode. We detect and analyze physiological indices of leaves and fruit after bleeding. The result revealed that the relative electrical conductivity and malondialdehyde (MDA) of leaves increased in treatment. Nitro blue tetrazolium chloride (NBT) and 3,3-diaminobenzidine (DAB) staining revealed the accumulation of reactive oxygen species (ROS) in leaves after bleeding. The chlorophyll content and photosynthetic parameter of plants were also decreased. In fruits, pulp and seed water content decreased after the damage, as did fruit vitamin C (Vc), soluble sugar content, and soluble solids content (SSC); the titratable acid content did not change significantly. We therefore conclude that bleeding affects the physiological indices of A. arguta. Our study provides a theoretical basis for understanding the physiological changes of A. arguta after bleeding episodes and laying a timely foundation for advancing research on A. arguta bleeding and long-term field studies should be executed in order to gain insights into underlying mechanisms. [ABSTRACT FROM AUTHOR]