• Title/Summary/Keyword: Fluctuating asymmetry

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Analysis of Facial Asymmetry

  • Choi, Kang Young
    • Archives of Craniofacial Surgery
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    • v.16 no.1
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    • pp.1-10
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    • 2015
  • Facial symmetry is an important component of attractiveness. However, functional symmetry is favorable to aesthetic symmetry. In addition, fluctuating asymmetry is more natural and common, even if patients find such asymmetry to be noticeable. However, fluctuating asymmetry remains difficult to define. Several studies have shown that a certain level of asymmetry could generate an unfavorable image. A natural profile is favorable to perfect mirror-image profile, and images with canting and differences less than $3^{\circ}-4^{\circ}$ and 3-4 mm, respectively, are generally not recognized as asymmetry. In this study, a questionnaire survey among 434 medical students was used to evaluate photos of Asian women. The students preferred original images over mirror images. Facial asymmetry was noticed when the canting and difference were more than $3^{\circ}$ and 3 mm, respectively. When a certain level of asymmetry is recognizable, correcting it can help to improve social life and human relationships. Prior to any operation, the anatomical component for noticeable asymmetry should be understood, which can be divided into hard tissues and soft tissue. For diagnosis, two-and three-dimensional (3D) photogrammetry and radiometry are used, including photography, laser scanner, cephalometry, and 3D computed tomography.

Comparative Analysis of Fluctuating Asymmetry between Ploidy and Sex in Marine Medaka, Oryzias dancena

  • Park, In-Seok;Gil, Hyun Woo
    • Development and Reproduction
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    • v.22 no.3
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    • pp.275-281
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    • 2018
  • The purpose of this study is to examine fluctuating asymmetry of eye diameter, maxilla length, operculum length, and the number of pectoral fin ray and pelvic fin ray between ploidy and sex in diploid and triploid marine medaka, Oryzias dancena. In all experimental groups, eye diameter and maxilla length showed no significant difference between left side and right side (p>0.05). Results of operculum length in triploid male group and pectoral fin ray's number in diploid male group showed similarity ones with results of operculum length in triploid female group and pectoral fin ray's number in diploid female group (p<0.05). However, the operculum length in diploid male group and pectoral fin ray's number in triploid male group showed consinderable difference with those of operculum length in diploid female group and pectoral fin in triploid female group. Findings of pelvic fin ray's number in all groups were similar to those of pectoral fin ray's number in all groups (p<0.01).

Asymmetries in Chickens from Lines Selected and Relaxed for High or Low Antibody Titers to Sheep Red Blood Cells

  • Tu, Yunjie;Siegel, P.B.
    • Asian-Australasian Journal of Animal Sciences
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    • v.28 no.3
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    • pp.323-327
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    • 2015
  • Wattle length, width, and area were measured to classify bilateral asymmetries in four lines of chickens. The lines were the S26 generation of White Leghorns selected for high (HAS) or low (LAS) response to sheep red blood cells and sublines in which selection had been relaxed for three generations (high antibody relaxed [HAR] and low antibody relaxed [LAR]). Antibody titers (AB) were greater for HAS than for HAR with both greater than for LAS and LAR which while different for males did not differ for females. The low antibody lines were heavier and reached sexual maturity at younger age than the high antibody lines. In general, wattle length, width, and area were greater in the low than high antibody lines. In 24 comparisons for bilaterality 18 exhibited fluctuating asymmetry and 6 exhibited directional asymmetry with 5 of the 6 being for wattle length. There was not a clear pattern for changes in degree of asymmetry when selection was relaxed for 3 generations. For females, the relative asymmetry (RA) of wattle area was larger ($p{\leq}0.05$) for HAR than for LAR and not different from the selected lines and relaxed lines. There were no differences among lines for RA of wattle length and width of females and wattle length, width, and area of males.

Radial Thrust of Single-Blade Centrifugal Pump

  • Nishi, Yasuyuki;Fukutomi, Junichiro;Fujiwara, Ryota
    • International Journal of Fluid Machinery and Systems
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    • v.4 no.4
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    • pp.387-395
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    • 2011
  • Single-blade centrifugal pumps are widely used as sewage pumps. However, the impeller of a single-blade pump is subjected to strong radial thrust during pump operation because of the geometrical axial asymmetry of the impeller. Therefore, to improve pump reliability, it is necessary to quantitatively understand radial thrust and elucidate the behavior and mechanism of thrust generating. This study investigates the radial thrust acting up on a single-blade centrifugal impeller by conducting experiments and CFD analysis. The results show that the fluctuating component of radial thrust increases as the flow rate deviates from the design flow rate to low or high value. Radial thrust was modeled by a combination of three components, inertia, momentum, and pressure by applying an unsteady conservation of momentum to the impeller. The sum of these components agrees with the radial thrust calculated by integrating the pressure and the shearing stress on the impeller surface. The behavior of each component was shown, and the effects of each component on radial thrust were clarified. The pressure component has the greatest effect on the time-averaged value and the fluctuating component of radial thrust. The time-averaged value of the inertia component is nearly 0, irrespective of the change in the flow rate. However, its fluctuating component has a magnitude nearly comparable with the pressure component at a low flow rate and slightly decreased with the increase in flow rate.

A STUDY ON THE SIZE OF THE DECIDUOUS TEETH (유치의 치아크기에 관한 연구)

  • Baik, Byeong-Ju;Jeon, So-Hee;Kim, Jae-Gon;Kim, Young-Sin
    • Journal of the korean academy of Pediatric Dentistry
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    • v.29 no.3
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    • pp.382-388
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    • 2002
  • In the present study, crown diameters and their sexual differences in deciduous teeth were investigated in children of Chon-ju city, Korea. Plaster casts of the deciduous dentitions obtained from 50 boys and 50 girls were examined. Mesiodistal and buccolingual crown diameters were measured using a digital caliper(0.01mm) according to the definitions of Seipel and Moorees et al. These measurements were performed three times, and intra-observer measurement errors were calculated by the single determination method. The crown index, module and area were calculated in order to provide a comparison of crown proportions. The results obtained were summarized as follows; 1. The mean values of intra-observer measurement errors were 0.255mm and are unlikely to have influenced the statistical analysis. 2. The mean values of mesiodistal and buccolingual crown diameters examined were larger in boys than girls. 3. The mean coefficient of variation was 5.6 in the deciduous dentition. There were a trend for the primary second molar to be the least variable in size of all teeth both in boys and girls. 4. Fluctuating asymmetry is the difference between left and right antimeres in individuals. Primary second molars were less asymmetrical than primary first molars in both dimensions. 5. In maxillary teeth, Crown index is larger in boys than in girls. In contrast, in mandibular teeth, except primary canine, it is larger in girls than in boys. Crown module is larger in boys than in girls and increased progressively from primary first incisor to primary second molar. Crown area is consistently larger in boys than in girls. The minimum crown area is mandibular primary incisor and maximum crown area is maxillary primary second molar.

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Effects of Housing Systems on Behaviour, Performance and Welfare of Fast-growing Broilers

  • Zhao, Zi-Guang;Li, Jian-Hong;Li, Xiang;Bao, Jun
    • Asian-Australasian Journal of Animal Sciences
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    • v.27 no.1
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    • pp.140-146
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    • 2014
  • This experiment aimed to evaluate the effects of different housing systems on behavioral activities, welfare and meat quality of fast-growing broilers. Two hundred broilers were allocated into two housing systems: indoor housing vs indoor with outdoor access. Their general behavior (feeding, drinking, fighting, standing, lying, walking, investigating, dust-bathing and preening) was observed, and tonic immobility, fluctuating asymmetry of legs and wings were measured, and meat quality was analyzed. The results showed that the indoor-housed broilers with outdoor access had significant higher standing, walking, investigating, dust-bathing and preening than those indoor only. However, farming system was not found to significantly affect their feeding, drinking and fighting activities (p>0.05). The value of FA of tibia length of the broilers with outdoor access was significantly lower than that of the indoor-housed birds ($1.57{\pm}1.30$ vs $2.76{\pm}1.40$, p<0.05), while no difference was found for the value of FA in tibia diameter and wing length (p>0.05). TI of the broilers with outdoor access was 165.5 that was significantly higher than that (147.2) of the indoor birds (p<0.05). However, death rate in the outdoor run groups was significantly higher than that of the indoor ones ($2.0{\pm}0.81$ vs $4.0{\pm}0.82$, p<0.05). Meat quality was not affected by the two farming systems. It can be concluded that the results of this study may suggest that the indoor housing with outdoor access provides enriched environment for broilers and facilitates the expression of natural behaviors of the broilers but resulted in poorer performance and higher death rate.

The effect of Reynolds number on the elliptical cylinder wake

  • Shi, Xiaoyu;Alam, Md. Mahbub;Bai, Honglei;Wang, Hanfeng
    • Wind and Structures
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    • v.30 no.5
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    • pp.525-532
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    • 2020
  • This work numerically investigates the effects of Reynolds number ReD (= 100 - 150), cross-sectional aspect ratio AR = ( 0.25 -1.0), and attack angle α (= 0° - 90°) on the forces, Strouhal number, and wake of an elliptical cylinder, where ReD is based on the freestream velocity and cylinder cross-section height normal to the freestream flow, AR is the ratio of the minor axis to the major axis of the elliptical cylinder, and α is the angle between the cylinder major axis and the incoming flow. At ReD = 100, two distinct wake structures are identified, namely 'Steady wake' (pattern I) and 'Karman wake followed by a steady wake (pattern II)' when AR and α are varied in the ranges specified. When ReD is increased to 150, an additional wake pattern, 'Karman wake followed by secondary wake (pattern III)' materializes. Pattern I is characterized by two steady bubbles forming behind the cylinder. Pattern II features Karman vortex street immediately behind the cylinder, with the vortex street transmuting to two steady shear layers downstream. Inflection angle αi = 32°, 37.5° and 45° are identified for AR = 0.25, 0.5 and 0.75, respectively, where the wake asymmetry is the greatest. The αi effectively distinguishes the dependence on α and AR of force and vortex shedding frequency at either ReD. In Pattern III, the Karman street forming behind the cylinder is modified to a secondary vortex street. At a given AR and α, ReD = 150 renders higher fluctuating lift and Strouhal number than ReD = 100.

A STUDY ON THE SIZE OF THE PERMANENT TEETH (영구치의 치아크기에 관한 연구)

  • Baik, Byeong-Ju;Park, Jeong-Yeol;Kim, Jae-Gon;Lee, Doo-Cheol
    • Journal of the korean academy of Pediatric Dentistry
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    • v.30 no.3
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    • pp.502-509
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    • 2003
  • After 800 students of Chonbuk National University was examined, 86 people (male : 43, female : 43, mean age : 22.2 years old) was selected as a group of normal occlusion. From their gypsum cast, this conclusion was obtained. 1. Intra-observer measurement errors in buccolingual diameter, maxillary lateral incisors have somewhat bigger errors. In mesiodistal diameter, maxillary first molars and maxillary second molar have bigger numerical value. Mean errors of measurement are 0.051mm at buccolingual diameter of crown and 0.083mm at mesiodistal diameter. 2. Fluctuating asymmetry is 0.030 average in buccolingual diameter, and 0.037 average in mesiodistal diameter. Statistically there are no big differences. 3. Male has longer buccolingual diameter than female in every permanent teeth. Teeth which have statistical difference in buccolingual diameter are maxillary lateral incisor, maxillary canine, maxillary second molar, mandibular central incisor, mandibular canine, mandibular second premolar, and mandibular first molar. In mesiodistal diameter maxillary central incisor, maxillary canine, and mandibular first molar have statistically difference. 4. Tooth which has the biggest difference depending on gender is maxillary lateral incisor in buccolingual diameter and mandibular canine in mesiodistal diameter. 5. Both sexes have similar crown index. Male has bigger value of crown module measurement and crown area measurement in every tooth. Crown area considered as size of tooth from occlusal surface was bigger in male than in female statistically except some teeth, maxillary first premolar, mandibular lateral incisor, first premolar and second premolar.

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