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Vascular bundles within maize (Zea mays L.) stalks play a key role in the mechanical support of plant architecture as well as in water and nutrient transportation. Convenient and accurate phenotyping of vascular bundles may help phenotypic identification of germplasm resources for breeding. Based on practical sample preparation procedures for maize stalks, we acquired serials of cross-sectional images using a micro-computed tomography (CT) imaging device. An image processing pipeline dedicated to the phenotyping of vascular bundles was also developed to automatically segment and validate vascular bundles from the cross-sectional images of maize stalks, from which phenotypic traits of vascular bundles, i.e. number, area, and spatial distribution, were calculated. More profound quantification of spatial distribution was given as area ratio of vascular bundles, which described the distribution of vascular bundles associated with the centroid of maize stalks. In addition, three-dimensional visualisation was performed to reveal the spatial configuration and distribution of vascular bundles. The proposed method significantly improves computation accuracy for the phenotypic traits of vascular bundles compared with previous methods, and is expected to be useful for illustrating relationships between phenotypic traits of vascular bundles and their function.

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Background:The prevalence of childhood asthma has been increasing in China. This study aimed to compare the prevalence, diagnosis, and treatment of asthmatic children from urban and rural areas in Beijing, China.Methods:Schools, communities, and kindergartens were randomly selected by cluster random sampling from urban and rural areas in Beijing. Parents were surveyed by the same screening questionnaires. On-the-spot inquiries, physical examinations, medical records, and previous test results were used to diagnose asthmatic children. Information on previous diagnoses, treatments, and control of symptoms was obtained.Results:From 7209 children in rural areas and 13,513 children in urban areas who completed screening questionnaires, 587 children were diagnosed as asthma. The prevalence of asthma in rural areas was lower than in urban areas (1.25% vs. 3.68%, χ2 = 100.80, P < 0.001). The diagnosis of asthma in rural areas was lower than in urban areas (48.9% vs. 73.9%, χ2 = 34.6, P < 0.001). Compared with urban asthmatic children (56.5%), only 35.6% of rural asthmatic children received inhaled corticosteroids (P < 0.05). The use of bronchodilators was also lower in rural areas than in urban areas (56.5% vs. 66.4%, χ2 = 14.2, P < 0.01).Conclusion:The prevalence of asthma in children was lower in rural areas compared with children in the urban area of Beijing. A considerable number of children were not diagnosed and inadequately treated in rural areas.

Aim: To describe our experience with various interventions for caesarean scar pregnancies (CSPs) based on the myometrial thickness between the gestational mass and the bladder. Methods: All patients were initially administered methotrexate. Then, the appropriate therapies hysteroscopy alone or combined with uterine artery embolization (group A) and direct laparoscopy alone or combined with laparoscopic uterine artery occlusion (group B) was selected based on the myometrial thickness between the gestational mass and the bladder. Results: The uteri of all 53 patients with CSPs were conserved; no conversion to laparotomy or blood transfusion was required. Uterine rupture occurred in one case during surgery in group A. The operative time in group B was longer than group A (42 ± 18 vs. 80 ± 33 min; p = 0.022). The two groups were also similar with respect to other characteristics (p > 0.05). Conclusion: Myometrial thickness should be considered during the management of CSPs. Surgical approaches in the treatment of CSPs using 2-mm boundaries may yield an optimal clinical outcome.