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We studied the reproductive biology of the endangered species Calocedrus macrolepis. We examined flower phenology and morphology, spatial distribution of male and female cones, pollen viability, variation in pollen density around the crown, and the pollination process. Calocedrus macrolepis is monoecious with unisexual flowers on the same branches. Pollen-shed from male cones occurred from early September to mid-February, whereas the female cones were receptive from mid-September to mid-March. The inconsistency of flowering periods between male and female cones within populations and among individuals extended the pollination period. There was a layered distribution pattern of male and female cones in the crown, with more male cones in the lower layer and more female cones in the upper layer. This resulted in different selfing and outcrossing rates at various locations. The pollen of C. macrolepis lack airbags, and consequently, it was dispersed within only 10 m of the mother tree. The short pollen dispersal distance could restrict gene flow among different geographical populations. Calocedrus macrolepis is endangered because of its high degree of selfing and inbreeding resulting from its monoecious characteristics and the short distance of pollen spread. These factors may result in a population decline. [ABSTRACT FROM AUTHOR]

SUMMARY: Rhododendrons are woody plants, famous throughout the world as having high horticultural value. However, many wild species are currently threatened with extinction. Here, we report for the first time a high‐quality, chromosome‐level genome of Rhododendron griersonianum, which has contributed to approximately 10% of all horticultural rhododendron varieties but which in its wild form has been evaluated as critically endangered. The final genome assembly, which has a contig N50 size of approximately 34 M and a total length of 677 M, is the highest‐quality genome sequenced within the genus to date, in part due to its low heterozygosity (0.18%). Identified repeats constitute approximately 57% of the genome, and 38 280 protein‐coding genes were predicted with high support. We further resequenced 31 individuals of R. griersonianum as well as 30 individuals of its widespread relative R. delavayi, and performed additional conservation genomic analysis. The results showed that R. griersonianum had lower genetic diversity (θ = 2.58e−3; π = 1.94e−3) when compared not only to R. delavayi (θ = 11.61e−3, π = 12.97e−3), but also to most other woody plants. Furthermore, three severe genetic bottlenecks were detected using both the Stairway plot and fastsimcoal2 analysis, which are thought to have occurred in the late Middle Pleistocene and the Last Glacial Maximum (LGM) period. After these bottlenecks, R. griersonianum recovered and maintained a constant effective population size (>25 000) until now. Intriguingly, R. griersonianum has accumulated significantly more deleterious mutations in the homozygous state than R. delavayi, and several deleterious mutations (e.g., in genes involved in the response to heat stress) are likely to have harmed the adaptation of this plant to its surroundings. This high‐quality, chromosome‐level genome and the population genomic analysis of the critically endangered R. griersonianum will provide an invaluable resource as well as insights for future study in this species to facilitate conservation and in the genus Rhododendron in general. Significance Statement: The high‐quality, chromosome‐level genome and the population genomic analysis of the critically endangered Rhododendron griersonianum provide an invaluable resource for future study as well as insights for future study in this species to facilitate conservation and in the genus Rhododendron in general. [ABSTRACT FROM AUTHOR]

The ureter injury occasionally happens in the gynecology, abdominal and urinary surgeries. The medical negligence may cause severe problems for the hospital, and mental pressure for the doctors. Furthermore, the serious accident brings painful complications for the patients. Thus, it is necessary to locate the ureter, which is covered by peritoneum and connective tissue, for the assisted surgery. The aim is to detect the ureter position, and avoid iatrogenic ureter injury. In order to indicate the ureter position in surgery, we propose an image-guided endoscope system that has both traditional functions of the endoscope system and the additional function of ureter detection. We design an infrared-based pipe that its shape is similar to the ureteral catheter to mark the ureter, and use the multi-spectral camera that can capture both the visual and infrared light to obtain the endoscopic images. To extract the precise contour of the ureter, we propose a hardware-aided detection method, and a high-efficient segmentation algorithm. The hardware-aided method is used to recognize the kind of the captured images. Then the ureter position is extract by the segmentation algorithm. Before the image segmentation, the image enhancement and denoising algorithms are executed to reduce the noise level of images. The extracted contour of the ureter is fused with visible-light images to generate the endoscopic images highlighting the location of ureter. Experimental results indicate that the proposed system can achieve 83.54% and 88.38% of true positive rate (TPR) and positive predictive value (PPV ) respectively. In addition, the frame rate is about 25 frames per second (f/s), which reaches the real-time performance. We proposed a novel image-guided endoscope system for the ureter detection, and the ureter position can be displayed during the surgery. The proposed system may reduce the ureter injury in surgery, and improve the surgical success rate. [ABSTRACT FROM AUTHOR]

Premise of the Study: A novel set of EST‐SSR markers was developed for Phyllanthus emblica (Phyllanthaceae) to investigate the genetic structure and gene flow, identify novel genes of interest, and develop markers for assisted breeding. Methods and Results: Based on the transcriptome data of P. emblica, 83 EST‐SSR primer pairs were designed; 52 primer pairs were successfully amplified, with 20 showing polymorphisms in 90 individuals from three populations of P. emblica. The number of alleles per locus varied from 11 to 44. The observed and expected levels of heterozygosity for the 20 loci ranged from 0.240 to 0.868 and 0.754 to 0.933, respectively. Cross‐species amplification was successful for all 20 loci in each of the two related species, P. reticulatus and Leptopus chinensis. Conclusions: These markers will be valuable for studying the population genetics and for mining genes of P. emblica, and may be useful for studies of related species. [ABSTRACT FROM AUTHOR]

Premise of the Study: To investigate the genetic background and population characteristics of Rhododendron longipedicellatum (Ericaceae), a newly discovered and critically endangered species, expressed sequence tag–simple sequence repeat markers were developed, and transferability was tested in two congeners, R. molle and R. simsii. Methods and Results: Based on the transcriptome sequences of R. longipedicellatum, 102 primer sets were designed; 48 primer sets were successfully amplified, with 15 showing polymorphisms in 150 individuals from five extant populations of R. longipedicellatum. The number of alleles per locus ranged from four to 18, and the levels of observed and expected heterozygosity for the 15 loci varied from 0.255 to 0.913 and from 0.306 to 0.851, respectively. All 15 loci were found to amplify in R. molle and R. simsii. Conclusions: These polymorphic SSR markers can be used in conservation genetic and phylogeographic studies to elucidate the rarity and origin of R. longipedicellatum. [ABSTRACT FROM AUTHOR]