• Title, Summary, Keyword: Cone sex ratio

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Cone Sex Ratio and Pollen Traits in Pinus densiflora (Pinaceae)

  • Kang, Hyesoon;Yoon, Jumsoon
    • Animal cells and systems
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    • v.4 no.2
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    • pp.131-140
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    • 2000
  • The pattern of variations in cone sex ratio and pollen traits such as pollen number and size was examined for two years in populations of red pines In Korea. We evaluated; (1) the relationship between tree size and cone sex ratio, (2) the relationship between year and cone sex ratio, and (3) the relationship between cone sex ratio and pollen traits. Larger trees in height and circumference at breast height produced more male as well as female cones. However, cone sex ratio was independent of these plant sizes. Across the two populations, both female cone numbers per tree and male cone numbers per new shoot increased 2.2 and 1.2 times, respectively, in 1999 compared to 1998, while the yearly pattern of male cone-bearing shoots per tree differed significantly between populations. Thus, cone sex ratio varied significantly between years in one of the two populations. Pollen traits such as the number of pollen grains and diameter did not vary significantly among populations. Pollen diameter and grain numbers per male cone were significantly negatively correlated with the cone sex ratio in two populations and one population, respectively. Trees which stopped female cone production in the first year and those which produced female cones in both years differed in the cone sex ratio and pollen size in the second year. The long duration of one reproductive episode and the potential of masting in red pines emphasize the need to conduct long-term studies on the dynamics of cone production, cone sex ratio, and simultaneous changes in pollen traits in red pines.

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Three dimensional evaluation of impacted mesiodens using dental cone beam CT (치과용 콘빔 CT를 이용한 상악 정중과잉치의 3차원 분석)

  • Lee, Dong-Ho;Lee, Jea-Seo;Yoon, Suk-Ja;Kang, Byung-Cheol
    • Imaging Science in Dentistry
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    • v.40 no.3
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    • pp.109-114
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    • 2010
  • Purpose : This study was performed to analyze the position, pattern of impacted mesiodens, and their relationship to the adjacent teeth using Dental cone-beam CT. Materials and Methods : Sixty-two dental cone-beam CT images with 81 impacted mesiodenses were selected from about 2,298 cone-beam CT images at Chonnam National University Dental Hospital from June 2006 to March 2009. The position, pattern, shape of impacted mesiodenses and their complications were analyzed in cone-beam CT including 3D images. Results : The sex ratio (M : F) was 2.9 : 1. Most of the mesiodenses (87.7%) were located at palatal side to the incisors. 79% of the mesiodenses were conical in shape. 60.5% of the mesiodenses were inverted, 21% normal erupting direction, and 18.5% transverse direction. The complications due to the presence of mesiodenses were none in 43.5%, diastema in 19.4%, tooth displacement in 17.7%, delayed eruption or impaction in 12.9%, tooth rotation in 4.8%, and dentigerous cyst in 1.7%. Conclusions : Dental cone-beam CT images with 3D provided 3-dimensional perception of mesiodens to the neighboring teeth. This results would be helpful for management of the impacted mesiodens.

Predictors of midpalatal suture expansion by miniscrew-assisted rapid palatal expansion in young adults: A preliminary study

  • Shin, Hyerin;Hwang, Chung-Ju;Lee, Kee-Joon;Choi, Yoon Jeong;Han, Sang-Sun;Yu, Hyung Seog
    • The korean journal of orthodontics
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    • v.49 no.6
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    • pp.360-371
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    • 2019
  • Objective: We sought to determine the predictors of midpalatal suture expansion by miniscrew-assisted rapid palatal expansion (MARPE) in young adults. Methods: The following variables were selected as possible predictors: chronological age, palate length and depth, midpalatal suture maturation (MPSM) stage, midpalatal suture density (MPSD) ratio, the sella-nasion (SN)-mandibular plane (MP) angle as an indicator of the vertical skeletal pattern, and the point A-nasion-point B (ANB) angle for anteroposterior skeletal classification. For 31 patients (mean age, 22.52 years) who underwent MARPE treatment, palate length and depth, MPSM stage and MPSD ratio from the initial cone-beam computed tomography images, and the SN-MP angle and ANB angle from lateral cephalograms were assessed. The midpalatal suture opening ratio was calculated from the midpalatal suture opening width measured in periapical radiographs and the MARPE screw expansion. Statistical analyses of correlations were performed for the entire patient group of 31 subjects and subgroups categorized by sex, vertical skeletal pattern, and anteroposterior skeletal classification. Results: In the entire patient group, the midpalatal suture opening ratio showed statistically significant negative correlations with age, palate length, and MPSM stage (r = -0.506, -0.494, and -0.746, respectively, all p < 0.01). In subgroup analyses, a strong negative correlation was observed with the palate depth in the skeletal Class II subgroup (r = -0.900, p < 0.05). Conclusions: The findings of this study indicated that age, palate length, and MPSM stage can be predictors of midpalatal suture expansion by MARPE in young adults.

Monitoring of Mythimna separata Adults by Using a Remote-sensing Sex Pheromone Trap (원격감지 성페로몬트랩을 이용한 멸강나방(Mythimna separata) 성충 예찰)

  • Jung, Jin Kyo;Seo, Bo Yoon;Cho, Jum Rae;Kim, Yong
    • Korean journal of applied entomology
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    • v.52 no.4
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    • pp.341-348
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    • 2013
  • We desinged and evaluated a remote-sensing sex pheromone trap for real-time monitoring of Mythimna separata (Lepidoptera: Noctuidae), a migratory insect in Korea. The system consisted of a modified cone-trap with a sex pheromone lure, a sensing module based on light interruption, a signal transmission module based on code division multiple access, a main electronic board for system control, a power supply based on a solar collector, a stainless steel-pole supporting the system, and a signal collection and display system based on an internet web page. The ratio (>92%) of the actual number of insects to the signal number in the remote-sensing trap was improved by sensing only within a limited period at night on the basis of the insect's circadian rhythm, control of signal sensitivity on the basis of sensing software programming, 1-h interval for signal transmission, and adjustment of the signal transmission program. The signal occurrence pattern in the remote-sensing trap was conclusively similar (correlation coefficient, >0.98) to the actual pattern of adult occurrence in the trap. The result indicated that the remote-sensing trap based on the attraction of the sex pheromone lure for M. separata has a promising potential for practical use. Occurrence of M. separata adults was observed several times in 2011 and 2012, and the peaks were sharp.

Open Bronchus Sign on CT: A Risk Factor for Hemoptysis after Percutaneous Transthoracic Biopsy

  • Kim, Hyungjin;Park, Chang Min;Yoon, Soon Ho;Hwang, Eui Jin;Lee, Jong Hyuk;Ahn, Su Yeon;Goo, Jin Mo
    • Korean Journal of Radiology
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    • v.19 no.5
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    • pp.880-887
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    • 2018
  • Objective: We hypothesized that open bronchi within target pulmonary lesions are associated with percutaneous transthoracic needle biopsy (PTNB)-related hemoptysis. We sought to analyze and compare patient characteristics and target features as well as biopsy-related factors between patients with and without PTNB-related hemoptysis. Materials and Methods: We retrospectively analyzed 1484 patients (870 males and 614 females; median age, 66 years) who had undergone 1569 cone-beam CT (CBCT)-guided PTNBs. Patient characteristics (sex, age, and pathologic diagnosis), nodule features (nodule type, size, location, and presence of an open bronchus in target nodules), and biopsy-related factors (biopsy needle size, pleura-to-target distance, blood test results, open bronchus unavoidability [OBU] index, etc.) were investigated. OBU index, which was assessed using the pre-procedural CBCT, was a subjective scoring system for the probability of needle penetration into the open bronchus. Univariate analysis and subsequent multivariate logistic regression analysis were conducted to reveal the independent risk factors for PTNB-related hemoptysis. For a subgroup of nodules with open bronchi, a trend analysis between the occurrence of hemoptysis and the OBU index was performed. Results: The independent risk factors for hemoptysis were sex (female; odds ratio [OR], 1.918; p < 0.001), nodule size (OR, 0.837; p < 0.001), open bronchus (OR, 2.101; p < 0.001), and pleura-to-target distance (OR, 1.135; p = 0.003). For the target nodules with open bronchi, a significant trend between hemoptysis and OBU index (p < 0.001) was observed. Conclusion: An open bronchus in a biopsy target is an independent predictor of hemoptysis, and careful imaging review may potentially reduce PTNB-related hemoptysis.