• Title/Summary/Keyword: Sex Characteristics

Search Result 1,993, Processing Time 0.03 seconds

Study of Asiatic Black Bear(Ursus thibetanus ussuricus) Hibernation Day and Temperature Distribution (반달가슴곰 동면일과 기온 분포에 관한 연구)

  • Kim, Jeong-Jin;Jung, Dae-Ho;Kim, Tae-Wook;Byun, Yoon-Seop;Lee, Sa-Hyun;Oh, Hong-Shik
    • Korean Journal of Environment and Ecology
    • /
    • v.33 no.5
    • /
    • pp.497-505
    • /
    • 2019
  • Winter hibernation in wildlife is a unique physiological mechanism for survival. For Asiatic black bears (ABBs, Ursus thibetanus ussuricus), hibernation is a very important but dangerous time for the cubs to be born. This study surveyed ABBs living in Mt. Jiri To examine the relationship between the temperature during hibernation and the hibernation days. The survey found that the average start and end dates of hibernation was December 7 and April 20, respectively. The average day of hibernation for females who gave birth was $167.8{\pm}22.6$ days. The average temperature of 5 days before hibernation was $0.6{\pm}4.1^{\circ}C$, the average temperature during hibernation was $1.3{\pm}2.43^{\circ}C$, and the average temperature of five days before the end of hibernation was $12.6{\pm}3.1^{\circ}C$. The hibernation days of the females that did not give birth to cubs and the males were $120.4{\pm}25.7$ days and $113.6{\pm}25.8$ days, respectively. The average temperatures of 5 days before hibernation was $2.1{\pm}4.2^{\circ}C$ and $-1.8{\pm}3.9^{\circ}C$, respectively. The average temperature during hibernation was $-0.2{\pm}1.6^{\circ}C$ and $-0.4{\pm}2.4^{\circ}C$. The average temperatures of five days before the end of hibernation were $7.8{\pm}3.6^{\circ}C$ and $7.8{\pm}4.4^{\circ}C$. These results indicate that females giving birth to cubs have higher hibernation days and average temperatures than the females that do not give birth and the males, which is due to the process of raising cubs during hibernation. The hibernating days and mean temperature for the groups in each lifecycle did not show any difference between the groups. This study is meaningful in that it disclosed the characteristics of hibernating intrinsic behaviors of ABBs. It observed the specific hibernation period and temperature of ABBs bears inhabiting in Mt. Jiri and examined the difference by sex, female(giving birth) and life cycle group according to temperature. The results of this study can be used to prevent the conflict between ABBs and humans in winter and spring and establish the preservation management plan.

Job Stress and Stress Coping Strategy among Workers in A Regional Statistics Office : A Preliminary Study (일 통계청 근무자의 직무스트레스와 스트레스 대처 방식에 대한 예비 연구)

  • Lee, Hyun-Soo;Yoon, Bo-Hyun;Oh, Eun-Joo;Sea, Young-Hwa;Kim, Kyung-Min;Jung, Haran;Kim, Moon-Doo;Baek, Man-Ki;Son, Eun-Rak;Jung, Ja-Young
    • Korean Journal of Psychosomatic Medicine
    • /
    • v.23 no.2
    • /
    • pp.93-99
    • /
    • 2015
  • Objectives : The purpose of this preliminary study was to investigate job stress and stress coping strategy among workers in a regional statistics office. Methods : A total of 133 workers in regional statistics office participated in this study and they were divided into two groups, survey group(n=109) and support group(n=24) depending on relation to statistical survey task. They were asked to respond to Short Form of Korean Occupational Stress Scale(KOSS-SF) and Stress Coping Strategy(SCS) to investigate sociodemographic characteristics, job stress, and stress coping strategy. Results : The proportion of the 133 participants in the sample was 59(44.4%) of men, 74(55.6%) of women. There were no significant differences in KOSS-SF scores in relation to age, sex, education, and marital status, while the KOSS-SF scores were significantly different between the two groups. In regard to the subscales of KOSS-SF, the two groups had significant differences in insufficient job control, interpersonal conflict, job insecurity, and organization system. In addition, the total score of KOSS-SF had a negative correlation with problem-focused coping strategy and social support coping strategy of SCS. Conclusions : Our results suggest that workers of survey group had more job stress compared to those who works in support group in regional statistical office. In addition, in comparison with workers of support group, both men and women of survey group get stressed when they were confronted with interpersonal conflicts. Our results suggest that using problem-focused coping and social support coping strategy lowers job stress.

Electroencephalographic Changes Induced by a Neurofeedback Training : A Preliminary Study in Primary Insomniac Patients (뉴로피드백 훈련에 의한 뇌파 변화 연구 : 일차성 불면증 환자에 대한 예비 연구)

  • Lee, Jin Han;Shin, Hong-Beom;Kim, Jong Won;Suh, Ho-Suk;Lee, Young Jin
    • Sleep Medicine and Psychophysiology
    • /
    • v.26 no.1
    • /
    • pp.44-48
    • /
    • 2019
  • Objectives: Insomnia is one of the most prevalent sleep disorders. Recent studies suggest that cognitive and physical arousal play an important role in the generation of primary insomnia. Studies have also shown that information processing disorders due to cortical hyperactivity might interfere with normal sleep onset and sleep continuity. Therefore, focusing on central nervous system arousal and normalizing the information process have become current topics of interest. It has been well known that neurofeedback can reduce the brain hyperarousal by modulating patients' brain waves during a sequence of behavior therapy. The purpose of this study was to investigate effects of neurofeedback therapy on electroencephalography (EEG) characteristics in patients with primary insomnia. Methods: Thirteen subjects who met the criteria for an insomnia diagnosis and 14 control subjects who were matched on sex and age were included. Neurofeedback and sham treatments were performed in a random order for 30 minutes, respectively. EEG spectral power analyses were performed to quantify effects of the neurofeedback therapy on brain wave forms. Results: In patients with primary insomnia, relative spectral theta and sigma power during a therapeutic neurofeedback session were significantly lower than during a sham session ($13.9{\pm}2.6$ vs. $12.2{\pm}3.8$ and $3.6{\pm}0.9$ vs. $3.2{\pm}1.0$ in %, respectively; p < 0.05). There were no statistically significant changes in other EEG spectral bands. Conclusion: For the first time in Korea, EEG spectral power in the theta band was found to increase when a neurofeedback session was applied to patients with insomnia. This outcome might provide some insight into new interventions for improving sleep onset. However, the treatment response of insomniacs was not precisely evaluated due to limitations of the current pilot study, which requires follow-up studies with larger samples in the future.

A Study on the Effects of Career Interrupted Women' Personal Attitude and Subjective Norm on Entrepreneurial Intention: Focusing on Moderating Effects on the Entrepreneurial Supporting Policy (경력단절여성의 창업행위에 대한 태도와 주관적 규범이 창업의도에 미치는 영향)

  • Choi, Jinsook;Lee, Namhee;Hwang, Kumju
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
    • /
    • v.14 no.4
    • /
    • pp.113-132
    • /
    • 2019
  • The degree of females' participation in corporate activity has been recently increased over the world and females' participation in economic activity may be new dynamic fuel for the Korean economy that falls into the vicious cycle of low growth. Start-up, therefore, has increasingly taken attention as an opportunity for females whose careers were interrupted to re-enter the labor market. The need for studies that examine factors influencing the decision of start-up is also increased along with the increase of the ratio of females' start-up. This study aims to verify effects of the women's characteristics(women discrimination, women's role conflict) and the human networks of females whose careers were interrupted, with the intention for entrepreneurial intention, which are mediated by personal attitudes and subjective norm suggested by Ajzen's Theory of Reasoned Action, based on an empirical research. The findings show that the human networks of females have an effect on attitudes toward start-up activity and subjective norm and the woman discrimination influence the personal attitudes. In contrast, the women's role conflict have no effect on both personal attitude toward start-up activity and subjective norm. This can be supposed as an outcome resulted from the subjects' low level of conflict caused by their sex roles, on their age distribution. The relation between subjective norm and entrepreneurial Intention seemed to be moderated by their perceived strong entrepreneurial supporting policy. Their attitudes toward start-up activity were found to have a mediating effect on the relation between the women discrimination, human networks and entrepreneurial Intention, while the subjective norm only mediated the relation between human networks and entrepreneurial Intention. Based on such results, this study attempts to suggest theoretical suggestions and the direction of various entrepreneurial supporting policy for the increase and the growth of start-up of females whose careers were interrupted, in Korea.

Local, Jobless Person, Homo Economicus, Three Axis of Kwak Hashin's Works (로컬, 룸펜, 경제적 인간, 곽하신 소설의 세 좌표)

  • Kim, Yang-Sun
    • Journal of Popular Narrative
    • /
    • v.26 no.3
    • /
    • pp.161-188
    • /
    • 2020
  • This paper seeks to expand the scale of literary history by restoring and analyzing the whole aspect of Kwak Hashin's works, which has so far been studied little. For this purpose, I notice the rupture of discontinuity of his works which is greatly divided into the colonial period and post Korean war period. And the characteristics of each works can be analyzed based on the three axis, local(colonial period), jobless person(post-war period), and Homo Economicus(some short stories, and popular novels in post-war period). In Chapter 2, 'Local-the world of Munjang', I evaluated that Kwak Hashin's novel, which had been published in the late 1930s in the Journal of Munjang, embodied anti-modern aesthetic consciousness, as clearly revealing the sorrow for disappearing things, the pre-modern sense of time, and the preference for local. In Chapter 3, 'Jobless Person' and Chapter 4, 'The State of All People's Struggle against All People, The Appearance of Homo Economicus', the Korean society in late 1950s, which entered underdeveloped capitalist countries after Korean war, can be characterized by two contrasting male-gender, one is the jobless, incompetent male, and the economic man on the other hand. In the late '50s, Lumpen(=Jobless Person) novels showed the problems of the Korean economy through incompetent male character. The intelligent men took the path to survival rather than morality or intimacy, projecting their own incompetence and anxiety to women/wives. In the popular novels Women's Song and The Shadow of the Fig Tree, achievement-oriented male figures who betrayed their colleagues, and exploited women's sex by using love relationships to rise to the top appeared. They can be defined as the Homo Economicus who embody the state of universal struggle against all people. These novels showed the formation of the masculinity in post Korean war period, which pursued the survival of the fittest, borrowing form of popular novel. As we have seen so far, Kwak Hashin needs to be re-evaluated as an writer who expanded the modern literary history in the outside of literature. He was the last generation writer written in Korean late colonial period, and provided the model of postwar literature by borrowing the form of journalism and popular novels.

Report on the Eradication of Nutria (Myocastor coypus Molina, 1782), an Invasive Alien Species, from Jeju-do, South Korea - Case of Songdang-ri, Jeju-si - (제주도 침입외래생물 Nutria (Mycastor coypus Molina, 1782)의 퇴치 사례 보고 - 제주시 송당지역의 사례 -)

  • Ga-Ram Kim;Jun-Won Lee;Seon-Mi Park;Sung-Hwan Choi;Young-Hun Jung;Hong-Shik Oh
    • Korean Journal of Environment and Ecology
    • /
    • v.36 no.6
    • /
    • pp.582-591
    • /
    • 2022
  • This study was conducted to eliminate Myocastor coypusMolina, 1782 (Nutria) from Jeju Special Self-Governing Province, South Korea. Habitat identification and eradication were carried out from September to November 2013, and a survey was carried out until June 2022 to check whether the eradication was successful. The habitat was identified with unmanned cameras, interviews, and literature surveys, and the capture was performed using the trapping method with food to attract nutria to the habitat area. The study area for the follow-up survey, which was set relatively wide considering nutria's home range, included wetlands and rivers within 4.0 km2 of the habitat area (eradication area). As a result, nutria's habitat was confirmed only at Songdang Ranch, Songdang-ri, of Jeju Island, with traces of habitat (footprints, excrement, and burrows) confirmed in waterways and ponds within the pasture. Eight individuals were captured, including four females, three males, and one individual in too advanced a state of decay to identify the sex. The follow-up survey thoroughly investigated the habitat and its surroundings, focusing on three areas with permanent water, Seongeup Reservoir, Cheonmi Creek, and Molsuni Pond, but no signs of habitat were identified. Therefore, it is determined that nutria inhabiting Jeju Island has been completely eradicated. It is believed that the successful eradication of nutria in the Jeju Special Autonomous Region was possible due to a synergy between 1) the eradication of nutria at the beginning of the settlement phase through rapid capture after confirming the nutria habitat and 2) the delayed expansion period because of rare presence of wetlands, where water is constantly stagnant, on Jeju Island. These results imply that quickly identifying the ecological characteristics of the species and preventing disturbances before they or at the beginning of the ecological disturbance through control and eradication at the initial stage of settlement before the expansion stage is an effective measure to cope with the influx of alien species.

Sexual Trauma Survivors and Their Mental Health: Assessing Based on Types of the Traumatic Event (성적 트라우마 경험자의 정신건강: 트라우마 사건유형에 따른 비교 분석)

  • Soyoung Choi;Hyeyun Kim;Sumi Chae
    • Health Policy and Management
    • /
    • v.34 no.2
    • /
    • pp.129-140
    • /
    • 2024
  • Background: The mental health issues caused by trauma can manifest differently depending on the characteristics of the traumatic event. Particularly, individuals who have experienced sexual trauma are known to have more negative mental health outcomes compared to those who have experienced non-sexual trauma. The mental health issues of individuals who have experienced sexual trauma are severe, and new forms of threats, such as digital sexual crimes, are emerging. This study aimed to investigate whether the type of traumatic event, particularly focusing on sexual trauma events, contributes to differences in mental health outcomes and to identify factors influencing suicidal ideation and potential post-traumatic stress disorder (PTSD) risk. Methods: Based on an online survey conducted nationwide among adults aged 20 to 50, participants were categorized based on the type of trauma they experienced (sexual trauma events and non-sexual trauma events). The study conducted propensity score matching (PSM) using demographic factors (sex, age group, subjective economic status, and marital status) and resilience protective factors (cognition of recoverability, social support, and protection experiences in childhood) as control variables, excluding the experience of sexual trauma events, to investigate their potential impact on mental health (suicidal ideation and potential PTSD risk). Subsequently, binary logistic regression analysis was conducted to identify factors influencing mental health. Results: Even after PSM, individuals who experienced sexual trauma exhibited more negative outcomes in terms of suicidal ideation and potential PTSD risk compared to those who experienced non-sexual trauma. The results of binary logistic regression analysis showed that sexual trauma survivors were 1.9 times more likely to have suicidal thoughts (odds ratio [OR], 1.911) and 2.5 times more likely to have a potential PTSD risk (OR, 2.472). Furthermore, as resilience protective factors became more negative, the likelihood of suicidal ideation and potential PTSD risk increased. Conclusion: This study emphasizes the importance of understanding and supporting individuals who have experienced sexual trauma, highlighting the necessity for strategies aimed at mitigating suicidal ideation and potential PTSD risk among sexual trauma survivors, while also facilitating recovery through the promotion of resilience protective factors.

A study on the distribution basis and aspect of teachers holding additional school health (양호겸직교사의 배치근거 및 분포양상)

  • Lee, Jeong Yim
    • Journal of the Korean Society of School Health
    • /
    • v.2 no.1
    • /
    • pp.58-90
    • /
    • 1989
  • This study was attempted to contribute to the development of school health by providing the basic data about the distribution basis and distribution aspect of teachers holding additional school health that are in charge of school health business in parimary schools, middle schools and high schools without any nurse-teacher. This study analyzed literatures about the history, related laws, organization and professional manpower of school health. The emphasis was set on the distribution basis of theachers holding additional school health. The results of this study are as following: 1. The school health of the world dates to the late 18th century in Europe where was free supplying with food for poor children. The school health of Korea orginated from smallpox vaccination which was executed with appearance of modern schools in the late 19th century. 2. The related laws of school health began as a part of Education Law with was constituted in 1949. By the School Health Law constituted in 1967 and the enforcement ordinance of School Health made firm the legal basis of school health. 3. The administrative organs of school health are the Ministry of Education in center and each Board of Education in cities and provinces. For the first time in 1979, the department of school health was established in the organization of the Ministry of Education. And at about the same time of establishment of the department of school health, health section was established in the department of social physical-training in locality. 4. In the manpower of school health which was presented in the related statute of school health, there are the ward chief of education, the superintendent of educational affair, of cities and districts, the mayors, the governors of provinces, the school managers, the principals, the school doctors, the school pharmacists, and the nurse-teachers, including teachers holding additional school health as the practical manpower of school health. 5. In order to get some information on distribution aspect of teachers additional school health, this study made up a questionnaire from August 3 to August 11, 1988. The subjects of this study were 212 leachers who took part in the yearly training for teachers holding additional school health from Kyunggi province, Chungbuk province and Jeonbuk province. The results of the questionnaire are as following: 1. The distribution percentages of teachers holding additional school health according to each Board of Education wich schools are subject to, are as following:70.1% (Kyunggi), 76.5% (Chungbuk), and 81.4% (Jeonbuk). There was a significant difference. The distribution percentages of teachers holding additional school health according to the school levels of 3 provinces are as following: 74.1% (Primary schools), 77.8% (Middle schools), 76.7% (High schools). There were little significant differences. 2. The distribution according to the general characteristics of the subject schools: There were 64.2 percent of primary schools and 35.8 percent of middle schools among 212 schools. 91. 5 percent of schools were located in districts. Public schools formed 55.7% and then national schools were higher in percentage than private schools. 58.5 percent of schools had 1-9 classes, 64.6 percent of schools had 101-500 students, and 90 percents of schools had 1-20 teachers. In considering student sex, the coed school showed the high distribution percentage (Primary schools : 100%, Middle schools: 81.6%). 3. The distribution according to the characteristics of teachers holding additional school health: 93.3 percent of teachers were female, and more than 60 percent of teachers were 20-29 years old. As the age got higher, the percentage became lower. There were little significant differences by marital status. In considering their educational status, 86.8 percent of teachers in primary schools were from teacher's colleges, and 64.5 percent of teachers in middle schools were from education colleges. In considering teaching career, 46.7 percent of teachers had teaching career of less than 2 years. 73.6 percent of teachers had held additional school health for less than one year. More than 80 percent of teachers had participated in the training one time or twice. More than 70 percent of teachers had 1-2 additional jobs except for the school health business. The motivation to hold additional school health is most caused by mandatory order, which accounts for more than 80.0 percent. In considering interesting degree concerning school health, lukewarm answer is the highest of 62.7 percent, followed by affirmative answer of 23.6 percent. In considering their contentment degree respecting additional school health job, "discontent or very discontent"is the highest of 47.6 percent. As a descontent reason of additional school health job, overwork is the highest factor of 37.9 percent. Among addiitional school health job, the most difficult affair is nursing service to be 34.0 percent, followed by health education of 31.6 percent. It testify the need of professional. The source of knowledge about school health has been acquired from masscommunication or private health experience, which account for as much as 56.1 percent. It shows seriousness of lack of professionalism. With regard to neccessity of school health experts, 95.8 percent represents absolute need. With above consideration of study results, I propose as follows : 1. I propose that the authorities concerned unify and improve statute respecting current school health which has not been steadfastly supporting school health business by ambiguity of expression and dualization. 2. I propose that the authorities concerned give the school manager, school staffs and parents of students educational chance with which they can acknowledge the importance of school health and in which they can participate as well as set up alternative policy plan to be albe to vitalize school health committee. 3. I propose that administrative organization practicable to taking totally charge of school health business is established within the Ministry of Education. 4. I propose that the authorities concerned back up and cooperate in an attempt by make school health better and desirable toward development by way of appointing qualitied health teachers on the basis of legally regular teacher staffs.

  • PDF

A Study on the Perceived Stress of Mothers in Neonatal Intensive Care Unit (신생아 중환자실에 입원한 환아 어머니의 스트레스)

  • Choi Sung Hee
    • Child Health Nursing Research
    • /
    • v.4 no.1
    • /
    • pp.60-75
    • /
    • 1998
  • The parents have much expectation upon the pregnancy and child birth, and in most cases, they expect the healthy parturient child. However, we can be placed on the high-risk conditions which have the physical, social and immature infant, due to the unexpected results, among the new-born. Accordingly, these high-risk newborn and premature infants will be mostly in NICU, which the concentrated medical treatment can be given, upon their conditions. After their birth and during these periods, they will be divided from the parents, and the nurse will accomplish the bringing-up activities which they can take care of the infant, expected by the parents after their birth. The hospitalization of high-risk newborn including these premature infants is the shocking experience to the parents of family, and thus they can feel the fear and uneasiness, and these reactions of parents are troubled in the behavior at the usual days, and cause the disorder and spiritless status, and these results break the supporting ability of parents, and cause the obstruction. Also, the unavoidable division between the parents and the children as like hospitalization of children can make the parents to feel the alienation emotionally, and this causes the results which the pride on the bringing-up ability of baby gets to be lost. These problems can cause the difficulties on the bonding or the parenting in the further days, and can be related to the neglect and abuse of children. Also, it is gradually increased to study and report which the emotional division by the physical division between the mother and the baby obstructs the normal affection course between the parent and the infant. The stress caused by the birth and the hospitalization of high-risk newborn, as like this, is important in the points which it can uncertainly affect the potential energy for the relationship of parent-child who are finally healthy. Accordingly, the significance and purpose of this study are to understand the contents and degree of stress which the parents of high-risk newborn including the immature child can be experienced from the hospitalization of ICU for their new borns, and thus to offer the basic program to the nursing intervention program for these. The subject of this study is the mother of newborn in NICU of 10 General Hospitals located at the 3one of Pusan, Korea from September 1997 to October 1997, and thus makes the subject of 95 person of parents who agreed to take part in the study and it is descriptive study related to the stress of mother having the newborn in NICU. The method is based on the preceding study related to the stress of mother having the experience of child hospitalization and chronic disease child, and then acquires the advice of specialists group as like 5 nursing professors, and then is amended and supplemented. Total number of questions is 43 items and consists of 5 factors as like medical treatment &nursing procedures, disease status & prognosis, role of parents, communication & inter-personal relationships, hospital environment, and is 5 point Likert Scale. The reliability of this study method is very highly shown to be Cronbach α=0.95. The collected data is analysed as Average, Frequency, Standard Deviation, T-test, ANOVA, Pearson Correlation Coefficient, Duncan multifulrange test by use of SPSS /PC (V7.5). The results of this study is summarized as under. 1. Every characteristics of subject is which the party of mother is 28.70age(±7.48) in the average ages, 51% in the high-school graduate, 38.5% in the christianity, total monthly income is 212.55 thousand won(±1.971), 74.5% in the housewife, 72.9% in the parents and children together living and the number of children to be 1.48person(± 0.6) in average, the recognition on the prognosis of baby is 74.0% in 'Don't know', the relationship with the husband after the hospitalization of babyis 37.3% in 'More Intimate', the relationship with the family of husband to be 48% in 'No-change', and the degree which is consulted with the husband about the baby is 55% in 'very frequently' and the visiting number per week is 4.59(±1.63) in average and the accompanying person in the time of visiting is which the number of husband is 56.3% and thus is the highest. The characteristics of baby is which the age is 21.88days(±16.47) after the birth in average, the sex to be 50 person in the female 52.1% and the order of birth to be 54.2% in the first chid, and the weight in the birth to be 2770gm(±610) and the height in the birth to be 46.26cm(±7.62) in aver age. The medical diagnosis is 37.5% in the premature infant, the career of hospitalization is 96.9% in 'None', and the operation plan is 90.6% in 'None' and the execution of operation is 88% in 'None' and the nursing of incubator is 55.2% in 'Yes', and the method of feeding is 50.5% in 'Oral' and the contents of feeding is 46.9% in the 'Milk'. 2. The total stress degree of subject is almost highly shown to be as 3.36(±0.86). If it is compared upon each cause, 'stress on disease status & prognosis' is highest 3.79(±1.28), and it is in the order of 'stress on medical treatment & nursing procedures' 3.70(±0.93), 'stress on hospital environment' 3.14(±0.86), 'stress on role of parents' 3.18(±0.92) and 'stress on communication & inter personal relationship' 2.62(± 0.77) 3. As the results of checking the notworthiness of stress degree upon each variable of subject, the variable showing the noted difference was the birth weight(γ=-0.16, P=0.04), birth height(γ=-0.23, P=0.03), nursing in the incubator(F=8.93, P=0.04), feed method(F=2.94, P=0.04). That is to say, it is shown which the smaller the birth weight is, the higher the stress degree of mother is noteworthily. Also, the smaller the birth height baby is, the higher the stress of mother is. In the incubator, it os shown which the mother whose baby is nursing in the incubator is higher in the stress degree than other mothers. Upon the feeding method of baby, that is to say, TPNis the highest, and it is shown in the order of NPO, Tube feeding, and P.O. feeding. When we review the above-mentioned results, as the status is serious, it is thought which we include the supporting nursing for coping with the stress of parents in the setting-up od nursing plan for the baby in the NICU.

  • PDF

Malacological Studies on Parafossarulus manchouricus(Gastropoda: Prosobranchia) in Korea (한국산(韓國産) 왜우렁(Parafossarulus manchouricus)의 패류학적(貝類學的) 연구(硏究))

  • Chung, Pyung-Rim
    • The Korean Journal of Malacology
    • /
    • v.1 no.1
    • /
    • pp.24-50
    • /
    • 1985
  • Five different populations of Parafossarulus manchouricus (Chongpyung, Chinju and Kunsan, Korea; and Japan and Taiwan), a population of Bitbynia (Gabbia) misella (Gongju, Korea) and two different populations of Bithynta tentaculata (Michigan, U.S.A. and Bodensee, Germany) were compared in regard to eff-laying characteristics, morphology, chromosome cytology, natural infections of parasites and ecology of habitats. A satisfactory culture method was devised for laboratory rearing of the snails. Tropical fish food (Terra SML) and powdered green leaves (Ceralife) were used as the main food sources for the snails. Benthic diatoms such as Navicula and Gomphonema from the periphyton were also essential for satisfactory growth, especially for the baby snails. The aquaria were stabilized with small stones from a local stream. Young P. manchouricus snails grew to adult size in about 54 days after hatching. They laid eggs 150-156 days after hatching. The whole cycle (birth to egg-laying) took approximately 5 months. The three species of bithyniid snails are iteroparous and lay eggs once a year. There were no major morphological differences in the shells of genera or subgenera studied here. They did exhibit the following rather minor differences. The shell of Parafossarulus has spirally raised ridges, and its apex is usually eroded; the other two genera lack these characteristics. The shell of B. (Gabbia) misella is small, nor exceeding 7.5 mm in length, while the shells of the other two species are larger, being more than 10 mm in length. Scanning electron microscopy (SEM) of the protoconch of P. manchouricus reveals nearly smooth sculpture with small, low, spiral wrinkles. This sculpture is quite different from that of the Hydrobiidae, a family to which the bithyniids are frequently assigned. Scanning electron microscopy of the radulae of the three bithyniid species showed that their radular morphologies are very similar, but there are some small differences, which may be species-specific. There were some statistical differences in shell heights between the Korean and the other populations of P. manchouricus, and between this species and the other two bithyniids as well. The shell differences between the several populations of Korean P. manchouricus may be related to environment. Edtails of the chromosome cycle of these bithyniid snails are similar to those reported for other snails. No specific differences were observed in the chromosome cycle between the various species and populations of snails employed in this study. Reporred for the first time in molluscs are two darkly stained "nucleolar organizers" during pachyterne stages of meiosis. Two different chromosome numbers were observed in the three bithyniid species: n=17 in B. tentaculata and P. manchouricus, and n=18 in B. (G.) misella. no sex chromosomes or supernumerary chromosomes were seen. There were no morphological differences in karyotypes of three Korean strains of P. manchouricus. The infection rates of cercariae of Clonorchis sinensis in Chinju and Kunsan strains of P. manchouricus were 0.14% and 1.25%, respectively. However, Clonorchis cercariae were found in Chongpyung strain of P. manchouriceu and Gongju strain of B. (G.) misella. The habitats of P. manchouricus around Jinyang Lake were relatively clean without any heavy pollution of aquatic microorganisms and organic materials during the period of this study. The levels of dissolved oxygen (D.O.) and biochemical oxygen demand (B.O.D.) of the water specimens sampled from the study areas ranged from 6.0 to 9.6 ppm and from 0.4 to 1.6 ppm, respectively. Eight metalic constituents from the water samples were also assayed, and all metalic ions detercted were remarkably low below the legal criteria. However, calcium ion in the water samples from the habitats of P. manchouricus was considerably higher than others.

  • PDF