• 제목/요약/키워드: Sex Ratio

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동중국해에 분포하는 개조개의 생식생물학적 연구 (Reproductive Biology of the Purplish Washington Clam, Saxidomus prupuratus in the East China Sea)

  • 김영섭;김영혜;김종빈;장대수;이동우;강현정
    • 한국패류학회지
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    • 제26권4호
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    • pp.261-265
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    • 2010
  • 개조개 표본은 동중국해의 진해만에서 잠수선에 의해 어획된 것을 2002년 1월부터 12월까지 매월 120개체씩 채집된 것이다. 생식소 발달단계는 비활성기 (11월-12월), 초기활성기 (11월-이듬해 1월), 후기활성기 (12월-이듬해 2월), 성숙기 (2월-5월과 10월), 산란기 (4월-12월) 등 5단계로 구분되었다. 주산란시기 6월부터 8월까지이었다. 성숙각장은 71-85mm로 추정되었다. 암컷과 수컷 성비는 유의한 차가 없었으므로 1:1이었다.

대마의 재식밀도별 섬유수량 및 성발현 비율 (Fiber Yield and Sex Ratio of Hemp in Different Planting Density)

  • 권병선;정동희;문윤호;천종은
    • 한국작물학회지
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    • 제41권2호
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    • pp.230-235
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    • 1996
  • 재식밀도가 대류의 자웅성의 발현과 섬유수량에 미치는 영향을 구명코자 1995년 3월부터 1995년 8월 까지 호남농업시험장 목포시험장 특작포장에서 시험한 결과를 요약하면 다음과 같다. 1. 경장은 재식밀도 60$\times$20cm(8,333주/10a)의 소식에서 가장 길었고, 경태는 재식밀도 40$\times$20cm:12,500주/10a)에서 가장 굵었다. 2. 피마율은 재식밀도 40$\times$5cm(50,000주/10a)의 최다 밀식구에서 가장 높았고, 섬유수량 역시 가장 높았다. 3. 자웅성비의 변화는 40$\times$5cm(50,000주/10a)에서 자성의 비율이 가장 높아서 밀식으로 인한 자성의 비율을 높이는 효과를 거둘 수 있었다.

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제주도 연안에 분포하는 창꼴뚜기(Loligo edulis)의 자원생물학적 연구 (Fisheries Biology of Swordtip Squid, Loligo edulis in Jeju Island, Korea)

  • 강현정;김영혜;이은희;이동우;장대수
    • 한국패류학회지
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    • 제25권1호
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    • pp.23-28
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    • 2009
  • 2006년 6월부터 11월까지 매월 1회씩 제주도 귀덕, 신산, 김녕, 강정 연안에서 정치망에 의해 채집된 창꼴뚜기를 대상으로 창꼴뚜기의 생식생물학적 특성에 관하여 연구하였다. 조사기간 동안 총 759 개체의 창꼴뚜기 중에서 암컷은 429 개체, 수컷은 330 개체로 나타났다. 암컷의 경우, 조사 기간 중 미숙, 중숙, 성숙, 완숙기의 개체들이 혼재하여 출현하였으며 산란이 가능한 완숙 개체는 조사기간 중 초기인 6월을 제외하고 모든기간에 걸쳐 관찰되었고, 11월에 출현비율이 가장 높았다. 수컷도 조사기간 중 미숙, 중숙, 성숙, 완숙기의 개체들이 혼재하여 출현하됐으며 생식소의 숙도가 방정이 가능한 성숙단계이상의 개체는 전 기간에 걸쳐 관찰되었고 완숙기의 개체는 암컷과 같이 11월에 출현비율이 가장 높았다. 창꼴뚜기가 산란에 참여하는 군성숙외투장을 알아본 결과 성숙외투장은 17.1cm 로 추정되었다.

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Growth and Sex Ratio of Juvenile Olive Flounder (Paralichthys olivaceus) at Different Size-ranks

  • Kim, Jong-Hyun;Kim, Hyun-Chul;Noh, Jae-Koo;Lee, Jeong-Ho;Kang, Jung-Ha;Kim, Kyung-Kil
    • Fisheries and Aquatic Sciences
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    • 제10권4호
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    • pp.191-195
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    • 2007
  • The aim of this study was to assess whether size-rank at the juvenile stage is associated with growth performance and sex ratio in olive flounder (Paralichthys olivaceus). Juveniles (mean body weight, $8.8{\pm}0.9\;g$) were selected from two age groups, with the high size-rank group (HSRG) fish in the upper 19.3-67.3% of 104 days post-hatching (dph) age group and the low size-rank group (LSRG) fish in the lower 9.0-55.7% of 116 dph age group. Triplicate groups of 100 fish were reared over 32 weeks. A heavier final body weight was observed in the HSRG ($360{\pm}12\;g$) compared to the LSRG ($315{\pm}9\;g$, P<0.05), whereas no differences in feed intake, feeding efficiency, and mortality were seen between the experimental groups. The percentage of females was significantly higher in the HSRG (51.7%) than in the LSRG (30.8%, P<0.05). In addition, a remarkable increase in growth was recorded in females, indicating that the relative frequency of females increased with a body weight increase. The results suggest that high size-rank juvenile olive flounder have better growth performance and a higher percentage of females, because females start growing faster than males before size grading occurs.

Causes of Child Mortality (1 to 4 Years of Age) From 1983 to 2012 in the Republic of Korea: National Vital Data

  • Choe, Seung Ah;Cho, Sung-Il
    • Journal of Preventive Medicine and Public Health
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    • 제47권6호
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    • pp.336-342
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    • 2014
  • Objectives: Child mortality remains a critical problem even in developed countries due to low fertility. To plan effective interventions, investigation into the trends and causes of child mortality is necessary. Therefore, we analyzed these trends and causes of child deaths over the last 30 years in Korea. Methods: Causes of death data were obtained from a nationwide vital registration managed by the Korean Statistical Information Service. The mortality rate among all children aged between one and four years and the causes of deaths were reviewed. Data from 1983-2012 and 1993-2012 were analyzed separately because the proportion of unspecified causes of death during 1983-1992 varied substantially from that during 1993-2012. Results: The child (1-4 years) mortality rates substantially decreased during the past three decades. The trend analysis revealed that all the five major causes of death (infectious, neoplastic, neurologic, congenital, and external origins) have decreased significantly. However, the sex ratio of child mortality (boys to girls) slightly increased during the last 30 years. External causes of death remain the most frequent origin of child mortality, and the proportion of mortality due to child assault has significantly increased (from 1.02 in 1983 to 1.38 in 2012). Conclusions: In Korea, the major causes and rate of child mortality have changed and the sex ratio of child mortality has slightly increased since the early 1980s. Child mortality, especially due to preventable causes, requires public health intervention.

Histologic Distribution of Pulmonary Tumors in Lebanon: A 5-Year Single Institution Experience

  • Kourie, Hampig Raphael;Rassy, Marc;Ghorra, Claude;Naderi, Samah;Kattan, Joseph
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권14호
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    • pp.5899-5902
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    • 2015
  • Background: To compare the current histologic distribution of lung cancer in Lebanon to the worldwide trends, according to the 2004 WHO Classification. Materials and Methods: 1,760 patients with a pulmonary pathology examination at Hotel-Dieu de France University Hospital between July 2009 and July 2014 were included. Results: Some 676 out of the total investigated patients (38.4%) had a lung tumor. In 665 (98.4%) the tumors were malignant, with a mean age at diagnosis of 63.8 years and a male/female (M/F) sex ratio of 1.7:1. Among the malignant tumors, 86.2% were epithelial tumors with a mean age at diagnosis of 64.8 years and an M/F sex ratio of 1.9. Other malignant tumors consisted of metastatic tumors (10.2%), lymphoproliferative tumors (2.1%) and mesenchymal tumors (1.5%). Most common carcinoma subtypes were adenocarcinoma (48.0%), squamous cell carcinoma (23.0%) and small cell carcinoma (13.3%). Carcinoid tumors were the only carcinoma subtype with an M/F sex ratio below 1 (0.7). Salivary gland tumors were the carcinoma with lowest mean age at diagnosis (45.5 years). Conclusions: The histologic distribution of lung tumors in Lebanon is similar to that in developed countries. We believe this resemblance is due to common smoking habits, known to be responsible for the increase of lung adenocarcinoma at the expense of other subtypes.

The difference in the location of the malar summit between genders in Southeast Asians with appropriate references

  • Jirawatnotai, Supasid;Sriswadpong, Papat
    • 대한두개안면성형외과학회지
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    • 제22권2호
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    • pp.78-84
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    • 2021
  • Background: Facial feminization surgery and malarplasty require information concerning facial features in the malar area. Such information varies as a function of sex and race. The objectives of this study aimed to quantitatively evaluate the location of malar prominence across sexes in the Southeast Asian population, and identify sex-specific differences in malar prominence using a combination of two-dimensional (2D) computed tomography (CT) and three-dimensional (3D) CT. Methods: The location of malar prominence was evaluated in 101 Thai adults, consisting of 52 men and 49 women. This study used both 2D CT and 3D CT to achieve greater accuracy, in which 2D CT was used to measure malar distance, malar summit width, facial width, and malar summitto-facial width ratio whereas 3D CT was used to evaluate the positional relationship between the zygomatic summit and four reference points of the zygoma. Results: The malar summit was positioned more laterally in males (p< 0.01) and was more projected in females (p= 0.01). The other 2D-parameters were wider in males. The ratio between the malar summit width and facial width showed similar results for both sexes. The vertical dimension did not show any statistically significant differences; however, a higher summit position was observed in males. Conclusion: The zygomatic summit is positioned more laterally in males and is more projected in females. However, the ratio was similar, which indicates that the male cranium is larger in size. Based on the results in this study, when facial feminization surgery or malarplasty is performed on a Southeast Asian patient, the malar bone should be reduced horizontally and moved forward for better outcomes.

기름가자미 Glyptocephalus stelleri의 군성숙도와 주 산란기 (Sexual Group Maturity and Main Spawning Period of Glyptocephalus stelleri (Teleostei: Pleuronectidae))

  • 신소령;김현진;오한영;이정식;송혜진;김재원
    • 한국해양생명과학회지
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    • 제7권1호
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    • pp.37-44
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    • 2022
  • 연구는 기름가자미의 성비, 군성숙도 및 주 산란기에 관한 정보를 얻기 위해 수행하였다. 성비(암:수)는 1:0.54 (n=189:103, 암컷 64.7%)였으며, 전장이 증가함에 따라 암컷의 비율이 높아지는 경향을 보였다. 난모세포 발달패턴은 동일 난소 내에서 여러 단계의 난모세포군이 확인되는 난군동기발달형이었다. 로지스틱 회귀모델에 의해 분석된 50% 성숙 전장은 암, 수 각각 28.51 cm과 30.49 cm였다. GSI는 암, 수 각각 4월과 3월에 가장 높았으며, 주 산란기는 4-5월로 분석되었다.

오미자의 화아(花芽) 발달과 성 발현에 미치는 하계전정의 영향 (Flower bud development and the influence of sex expression of summer pruning in Schizandra chinensis Baillon)

  • 김선;김태수;박문수;박호기
    • 한국약용작물학회지
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    • 제11권2호
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    • pp.97-101
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    • 2003
  • 자웅동주 단성화인 오미자의 화아형성 및 성 결정 시기를 밝혀 기초연구의 토대를 마련하고, 전정을 통해 암꽃 착생량을 증가시키고자 수행하였던 시험결과는 다음과 같다 1. 오미자의 화아 형성은 6월 상순에 시작되었으며 7월 상순 완료되었다. 2. 익년 결실지와 동아는 9월 성장이 완료되었다. 3. 전정구의 2차 생장지 발생은 34-56%로 높았으나 7월1일 10절 처리는 25%로 낮았다. 4. 전정된 가지들의 개화비율은 $13{\sim}31.3%$로 무처리 가지의 개화비율 36.7%보다 낮았고 가지별 암꽃 착생량도 무처리보다 적은 경향이어서 전정에 의한 암꽃착생 증진 효과는 없었다.

SEX RATIOS OF NATURAL POPULATION OF IXODID TICKS IN PASTURE GROWN IN BANGLADESH

  • Giasuddin, M.;Haq, M.M.;Mondal, M.M.H.;Sarker, N.R.
    • Asian-Australasian Journal of Animal Sciences
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    • 제8권6호
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    • pp.647-650
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    • 1995
  • The study on the sex ratios of natural population of Ixodid ticks in pasture was conducted in the Bangladesh Agricultural University Campus, Mymensingh, from 1988 to June 1990. The samples were collected from the five grazing fields consisting of five different vegetations. Dragging methods were used for the collection of samples. In 24 months of observations a total of 1113 ticks of two different species, Boophilus microplus (670), Haemaphysalis bispinosa (443) were collected and their sex ratio was determined. Females were recorded higher in both B. microplus and H. bispinosa.