Artificial insemination of cryopreserved semen is not practiced in broiler breeder industry although its benefit has been recognized for years. Thus, the present study explored the possibility of artificial insemination with cryopreserved semen in Ross broiler breeders. Sixty Ross female broiler breeders were artificially inseminated either with fresh or with cryopreserved semen pooled from five male Ross broiler breeders. On.e hundred eighty eggs were collected from each semen treatment and hatched. Fertility and hatchability of fertilized eggs collected from hens artificially inseminated with cryopreserved semen were 68.0 and 47.1%, respectively, compared to 88.3 and 87.2% with fresh semen. Both unfertilized eggs and dead embryos during hatch were significantly (P<0.05) higher in the cryopreserved sementreated group by approximately 2.7 and 3.2fold than the fresh sementreated counterparts. the moderately low fertility and markedly low hatchability of fertilized eggs obtained from cryopreserved semen observed in this study may be of practical interests in broiler breeder industry and deserves further study.
Purpose: The purpose of this study is to clarify the social stigma phenomenon in teachers' perceptions and attitudes toward students who are classified as mental health support needs students in middle and high schools. Methods: Qualitative research was conducted through in-depth interviews and observations of 17 teachers and 2 consultants from 2 middle and high schools in Green City, which were evaluated as successful among the six pilot project schools designated by the Ministry of Education in 2013. The study's analysis is based on Hatch's hermeneutical method. Common categories were developed from the interviews and observations. Then, inferences were made per category and given importance to draw conclusions and lessons. Results: Teachers had a strong stigma in their perceptions of and attitudes to special needs students. Their perception was that those students are bound to go wrong due to family problems, even some having difficulty breathing, and that it's beyond their limit to help them. In addition, their attitudes included stereotypes, favoritism, punishment, and referral to experts. As a result, teachers did not expect those students would be cured or change and showed passive attitudes while shifting the responsibility to families and experts. Conclusion: This study is meaningful in that it showed the limitations of the role of teachers regarding mental health support needs students from the perspective of the teachers themselves. Today, when students' mental health problems are emerging as a serious issue, it is necessary to provide support to improve teacher's awareness and capabilities regarding adolescent mental health problems. In addition, we suggest the current selective policy that sorts out special needs students and provides care for them to evolve into a universal policy that improves public awareness and focus on prevention.
A comparative study was conducted to examine the effects of mixed and separate gender feeding on growth performance of Korean native chickens (KNC) against a white semi-broiler (WSB) and a commercial broiler (CB) over five weeks. 576 chicks were used with eight birds per cage in a randomized complete block design with 18 replicates per breed. For the KNC lines, three groups of male (M), female (F) and mixed-gender (FM) were used. Fresh water and feed were supplied on an ad-libitum basis. Birds were fed a standard starter (d 1 - 22) and grower diet (d 23 - 35). Body weight (BW), feed intake, and shank length (SL) were measured weekly. From the BW and feed consumed data, the average daily feed intake (ADFI), average daily gain (ADG), and feed conversion ratio (FCR) were calculated. The commercial broiler showed higher performance (p < 0.05) for all the indices measured for the entire period. The CB group consumed more feed and were more feed-efficient thus grew faster. This group was followed by the white semi-broiler and the KNC, in order. An intra-breed comparison for KNCs revealed that the males showed better growth performance with longer SL (p < 0.05) compared to the female and mixed-gender groups. The results showed that other than the breed type, mixed and separate gender feeding impacted on the growth performance of the two lines of Korean native chickens. Males for both lines of KNC generally performed better for the parameters measured, as determined by a greater BW and reduced FCR.
Journal of the Korean Society of Manufacturing Process Engineers
/
v.20
no.10
/
pp.27-37
/
2021
The use of additive manufacturing processes for the repair and remanufacturing of mechanical parts has attracted considerable attention because of strict environmental regulations. Directed energy deposition (DED) is widely used to retrofit mechanical parts. In this study, finite element analyses (FEAs) were performed to investigate the influence of the substrate phase and inclination angle on the heat transfer characteristics in the vicinity of Hastelloy X regions deposited via DED. FE models that consider the bead size and hatch distance were designed. A volumetric heat source model with a Gaussian distribution in a plane was adopted as the heat flux model for DED. The substrate and the deposited powder were S45C structural steel and Hastelloy X, respectively. Temperature-dependent thermal properties were considered while performing the FEAs. The effects of the substrate phase and inclination angle on the temperature distributions and depth of the heat-affected zone (HAZ) in the vicinity of the deposited regions were examined. Furthermore, the influence of deposition paths on depths of the HAZ were investigated. The results of the analyses were used to determine the suitable phase and inclination angle of the substrate as well as the appropriate deposition path.
Kim, Seulbi;Kim, Ho Myeong;Seo, Hye Jeong;Yeon, Jehyeong;Park, Ae Ran;Yu, Nan Hee;Jeong, Seul-Gi;Chang, Ji Yoon;Kim, Jin-Cheol;Park, Hae Woong
Journal of Microbiology and Biotechnology
/
v.32
no.8
/
pp.960-966
/
2022
Lactic acid bacteria (LAB) exert antagonistic activity against root-knot nematodes, mainly by producing organic acids via carbohydrate fermentation. However, they have not yet been used for root-knot nematode (Meloidogyne incognita) control owing to a lack of economic feasibility and effectiveness. In this study, we aimed to isolate organic acid-producing LAB from kimchi (Korean traditional fermented cabbage) and evaluated their nematicidal activity. Among the 234 strains isolated, those showing the highest nematicidal activity were selected and identified as Lactiplantibacillus plantarum WiKim0090. Nematicidal activity and egg hatch inhibitory activity of WiKim0090 culture filtrate were dose dependent. Nematode mortality 3 days after treatment with 2.5% of the culture filtrate was 100%, with a 50% lethal concentration of 1.41%. In pot tests, the inhibitory activity of an L. plantarum WiKim0090-copper sulfate mixture on gall formation increased. Compared to abamectin application, which is a commercial nematicide, a higher control value was observed using the WiKim0090-copper sulfate mixture, indicating that this combination can be effective in controlling the root-knot nematode.
Ki-Hyun Jeon;Jong-Hwan Jang;Sora Kang;Hak Seung Lee;Min Sung Lee;Jeong Min Son;Yong-Yeon Jo;Tae Jun Park;Il-Young Oh;Joon-myoung Kwon;Ji Hyun Lee
Korean Circulation Journal
/
v.53
no.11
/
pp.758-771
/
2023
Background and Objectives: Paroxysmal atrial fibrillation (AF) is a major potential cause of embolic stroke of undetermined source (ESUS). However, identifying AF remains challenging because it occurs sporadically. Deep learning could be used to identify hidden AF based on the sinus rhythm (SR) electrocardiogram (ECG). We combined known AF risk factors and developed a deep learning algorithm (DLA) for predicting AF to optimize diagnostic performance in ESUS patients. Methods: A DLA was developed to identify AF using SR 12-lead ECG with the database consisting of AF patients and non-AF patients. The accuracy of the DLA was validated in 221 ESUS patients who underwent insertable cardiac monitor (ICM) insertion to identify AF. Results: A total of 44,085 ECGs from 12,666 patient were used for developing the DLA. The internal validation of the DLA revealed 0.862 (95% confidence interval, 0.850-0.873) area under the curve (AUC) in the receiver operating curve analysis. In external validation data from 221 ESUS patients, the diagnostic accuracy of DLA and AUC were 0.811 and 0.827, respectively, and DLA outperformed conventional predictive models, including CHARGE-AF, C2HEST, and HATCH. The combined model, comprising atrial ectopic burden, left atrial diameter and the DLA, showed excellent performance in AF prediction with AUC of 0.906. Conclusions: The DLA accurately identified paroxysmal AF using 12-lead SR ECG in patients with ESUS and outperformed the conventional models. The DLA model along with the traditional AF risk factors could be a useful tool to identify paroxysmal AF in ESUS patients.
For the environmental friendly management of diamondback moth, Plutella xylostella (L.), Bacillus thuringiensis subsp. kurstaki ($30{\times}10^8\;cfu/mg$) and neem oil (0.5% azadirachtin) were used as green control agencies with mixed and alternative treatments on the chinese cabbage. When Bacillus thuringiensis subsp. kurstaki was applied to 1st and 2nd larva of P. xylostella with recommended concentration, their mortalities were reached to 100% by 2 days after treatment. In case of azadirachtin, its effect of mortality was continued for 7 days, and reached to 100% mortality. $LC_{50}$ values of Bacillus thuringiensis subsp. kurstaki and azadirachtin against 1st, 2nd, 3rd and 4th larva of P. xylostella were $2.8{\times}10^4$, $3.1{\times}10^4$, $3.4{\times}10^4$ and $1.5{\times}10^5\;cfu/ml$, and 2.7, 3.9, 4.7 and 7.1 ppm, respectively. The number of laid eggs of P. xylostella was reduced to 57.5 at 25 ppm of azadirachtin compared with control treatment. The hatch ratio was not significantly different with Bacillus thuringiensis subsp. kurstaki treatment in comparison with control treatment. However, when azadirachtin was applied, their hatch ratio were reduced to 25.8 and 45.4% at 25 and 50 ppm, respectively. On the other hand, emergence rate of eggs was not different with Bacillus thuringiensis subsp. kurstaki treatment, but 45.4% was shown in azadirachtin treatment with 50 ppm in comparison with control. When the mixture with Bacillus thuringiensis subsp. kurstaki and azadirachtin was applied to adults of P. xylostella, their mortality was higher than Bacillus thuringiensis subsp. kurstaki treatment only. These results are supposed that the mixture of Bacillus thuringiensis subsp. kurstaki and azadirachtin might be used as green control agents for reducing the demage of diamondback moth in the Chinse cabbage.
Temperature effects on diapause termination of Paratlanticus ussuriensis eggs were studied by measuring embryonic development and hatching rates at various conditions of indoor chilling and overwintering temperatures. Diapausing eggs of P. ussuriensis did not hatch at continued incubation at $25^{\circ}C$ and even after chilling for once at either $5^{\circ}C$ or $10^{\circ}C$ for 30, 45 and 60 days. In addition, double chillings at $5^{\circ}C$ with a 90 days interval at $25^{\circ}C$ did not induce hatching of diapausing eggs. However, double chillings at $10^{\circ}C$ induced hatching at 3.6${\sim}$26.7%. When eggs were incubated at $25^{\circ}C$ after chilling for once at $5^{\circ}C$ for various periods, those weights were not changed but those chilled at $10^{\circ}C$ gradually increased to approximately 1.5 times. When 60-days-old eggs were artificially deposited under the soil at three different mountain sites in September 2007, the hatching rates of the first-overwintered eggs were 11.3, 3.5 and 4.1% and those of the second-overwintered eggs were 25.1, 21.6 and 0.4% at Hoepori, Bitanri and Hwasanri, respectively. Most eggs were hatched from mid-March to mid-April but little bit earlier in southern regions. During the hatching period soil temperatures in three tested locations were around 8 to $12^{\circ}C$. In overall, diapausing eggs of P. ussuriensis were greatly influenced by chilling temperature conditions and those repeated cycles, and may required overwintering for one or two times to hatch for the post-embryonic development.
To investigate the cause of the mass mortality during rockbream, Oplegnathus fasciatus seed production, the water quality and bacterial counts of sea water in breeding tanks was measured 20days post the hatch. During breeding of rockbream fry, the environmental factors of water quality were detected as pH, ammonia COD, phosphate at the supply of the food organisms and the seawater. pH was decreased from the 8.21 of the 1 day per hatch (dph) to 7.56 of the on the 7 dph. Ammonia was conversely increased 0.49 ppm of the 1 dph to 0.85 ppm of 10 dph. As the adding of the chlorella and the rotifer tanks, COD was increased the 3.3 times and 1.2 times than those of pre-adding respectively. The phosphate and the ammonia were also increased 1.7 and 2.3 times, with adding the chlorella respectively, which exceeded the second grade for sea water evaluation level, 0.015 ppm and 0.1 ppm respectively. Water quality was not improved by PSB (Photosynthetic Bacteria) treatment, which increased the value of COD in 1.7 times, phosphate in 2.7 times and ammonia in 1.4 times. The number of the bacteria was also increased along the dph. According to the treatment of chlorella, the number of total bacteria increased in 1.4 times and those of Vibrio sp. 1.6 times. The lethal concentration of ammonia was investigated that over than 10 ppm could killed the fry of rockbream within 28 hrs, but 40% in 2 ppm.
This study was carried out to reveal the effect of temperature, salinity and aeration on maturation and hatching of Fibricola seoulensis eggs. The eggs were incubated and were observed daily for the appearance of eyespots and hatching. The results were summarized as follows. 1. From $4{\sim}5$ days after incubation in distilled water at $28^{\circ}C$ or at $11{\sim}26^{\circ}C$, the eyespots began to appear and the rates of eggs with eyespots were over 90% in $28^{\circ}C$ on the 7th or 8th day. However, eyespots did not appear in $5{\sim}15^{\circ}C$ or $4^{\circ}C$ by the 18th day. 2. The mature eggs began to hatch at the 8th day, and hatching rate 2 weeks after incubation was over 90% at $28^{\circ}C$, but it was below 5% at $11{\sim}26^{\circ}C$, and 0% at $5{\sim}15^{\circ}C$ and at $4^{\circ}C$. 3. Aeration did not influence the appearance of eyes pots nor hatching. 4. In salines under 0.6%, the rates of eyespots appearance were over 90% on the 7th day. The rate was 55.0% in 0.9% at 20 days, and 0% in 1.2%. 5. The hatching rates in salines below 0.3% concentration were over 90% by 14 days of incubation. However, the rate decreased to 44% in 0.6% saline and to 0% over 0.9% salinity. 6. The eggs incubated in the dark hatched in 12.5% on the 10th day, but hatching rate of mature eggs increased to 85.7% within 2 hours after exposure to light. Above results demonstrated that the best temperature for maturation and hatching of F. seoulensis eggs was $28^{\circ}C$, and the miracidia began to hatch at $8{\sim}9$ days after incubation. In the field, hatching and invasion into snails of the miracidia may occur from May to September in Korea. In salines under 0.3% concentration maturation and hatching were not influenced, but as salinity increased hatching was inhibited more than maturation was.
본 웹사이트에 게시된 이메일 주소가 전자우편 수집 프로그램이나
그 밖의 기술적 장치를 이용하여 무단으로 수집되는 것을 거부하며,
이를 위반시 정보통신망법에 의해 형사 처벌됨을 유념하시기 바랍니다.
[게시일 2004년 10월 1일]
이용약관
제 1 장 총칙
제 1 조 (목적)
이 이용약관은 KoreaScience 홈페이지(이하 “당 사이트”)에서 제공하는 인터넷 서비스(이하 '서비스')의 가입조건 및 이용에 관한 제반 사항과 기타 필요한 사항을 구체적으로 규정함을 목적으로 합니다.
제 2 조 (용어의 정의)
① "이용자"라 함은 당 사이트에 접속하여 이 약관에 따라 당 사이트가 제공하는 서비스를 받는 회원 및 비회원을
말합니다.
② "회원"이라 함은 서비스를 이용하기 위하여 당 사이트에 개인정보를 제공하여 아이디(ID)와 비밀번호를 부여
받은 자를 말합니다.
③ "회원 아이디(ID)"라 함은 회원의 식별 및 서비스 이용을 위하여 자신이 선정한 문자 및 숫자의 조합을
말합니다.
④ "비밀번호(패스워드)"라 함은 회원이 자신의 비밀보호를 위하여 선정한 문자 및 숫자의 조합을 말합니다.
제 3 조 (이용약관의 효력 및 변경)
① 이 약관은 당 사이트에 게시하거나 기타의 방법으로 회원에게 공지함으로써 효력이 발생합니다.
② 당 사이트는 이 약관을 개정할 경우에 적용일자 및 개정사유를 명시하여 현행 약관과 함께 당 사이트의
초기화면에 그 적용일자 7일 이전부터 적용일자 전일까지 공지합니다. 다만, 회원에게 불리하게 약관내용을
변경하는 경우에는 최소한 30일 이상의 사전 유예기간을 두고 공지합니다. 이 경우 당 사이트는 개정 전
내용과 개정 후 내용을 명확하게 비교하여 이용자가 알기 쉽도록 표시합니다.
제 4 조(약관 외 준칙)
① 이 약관은 당 사이트가 제공하는 서비스에 관한 이용안내와 함께 적용됩니다.
② 이 약관에 명시되지 아니한 사항은 관계법령의 규정이 적용됩니다.
제 2 장 이용계약의 체결
제 5 조 (이용계약의 성립 등)
① 이용계약은 이용고객이 당 사이트가 정한 약관에 「동의합니다」를 선택하고, 당 사이트가 정한
온라인신청양식을 작성하여 서비스 이용을 신청한 후, 당 사이트가 이를 승낙함으로써 성립합니다.
② 제1항의 승낙은 당 사이트가 제공하는 과학기술정보검색, 맞춤정보, 서지정보 등 다른 서비스의 이용승낙을
포함합니다.
제 6 조 (회원가입)
서비스를 이용하고자 하는 고객은 당 사이트에서 정한 회원가입양식에 개인정보를 기재하여 가입을 하여야 합니다.
제 7 조 (개인정보의 보호 및 사용)
당 사이트는 관계법령이 정하는 바에 따라 회원 등록정보를 포함한 회원의 개인정보를 보호하기 위해 노력합니다. 회원 개인정보의 보호 및 사용에 대해서는 관련법령 및 당 사이트의 개인정보 보호정책이 적용됩니다.
제 8 조 (이용 신청의 승낙과 제한)
① 당 사이트는 제6조의 규정에 의한 이용신청고객에 대하여 서비스 이용을 승낙합니다.
② 당 사이트는 아래사항에 해당하는 경우에 대해서 승낙하지 아니 합니다.
- 이용계약 신청서의 내용을 허위로 기재한 경우
- 기타 규정한 제반사항을 위반하며 신청하는 경우
제 9 조 (회원 ID 부여 및 변경 등)
① 당 사이트는 이용고객에 대하여 약관에 정하는 바에 따라 자신이 선정한 회원 ID를 부여합니다.
② 회원 ID는 원칙적으로 변경이 불가하며 부득이한 사유로 인하여 변경 하고자 하는 경우에는 해당 ID를
해지하고 재가입해야 합니다.
③ 기타 회원 개인정보 관리 및 변경 등에 관한 사항은 서비스별 안내에 정하는 바에 의합니다.
제 3 장 계약 당사자의 의무
제 10 조 (KISTI의 의무)
① 당 사이트는 이용고객이 희망한 서비스 제공 개시일에 특별한 사정이 없는 한 서비스를 이용할 수 있도록
하여야 합니다.
② 당 사이트는 개인정보 보호를 위해 보안시스템을 구축하며 개인정보 보호정책을 공시하고 준수합니다.
③ 당 사이트는 회원으로부터 제기되는 의견이나 불만이 정당하다고 객관적으로 인정될 경우에는 적절한 절차를
거쳐 즉시 처리하여야 합니다. 다만, 즉시 처리가 곤란한 경우는 회원에게 그 사유와 처리일정을 통보하여야
합니다.
제 11 조 (회원의 의무)
① 이용자는 회원가입 신청 또는 회원정보 변경 시 실명으로 모든 사항을 사실에 근거하여 작성하여야 하며,
허위 또는 타인의 정보를 등록할 경우 일체의 권리를 주장할 수 없습니다.
② 당 사이트가 관계법령 및 개인정보 보호정책에 의거하여 그 책임을 지는 경우를 제외하고 회원에게 부여된
ID의 비밀번호 관리소홀, 부정사용에 의하여 발생하는 모든 결과에 대한 책임은 회원에게 있습니다.
③ 회원은 당 사이트 및 제 3자의 지적 재산권을 침해해서는 안 됩니다.
제 4 장 서비스의 이용
제 12 조 (서비스 이용 시간)
① 서비스 이용은 당 사이트의 업무상 또는 기술상 특별한 지장이 없는 한 연중무휴, 1일 24시간 운영을
원칙으로 합니다. 단, 당 사이트는 시스템 정기점검, 증설 및 교체를 위해 당 사이트가 정한 날이나 시간에
서비스를 일시 중단할 수 있으며, 예정되어 있는 작업으로 인한 서비스 일시중단은 당 사이트 홈페이지를
통해 사전에 공지합니다.
② 당 사이트는 서비스를 특정범위로 분할하여 각 범위별로 이용가능시간을 별도로 지정할 수 있습니다. 다만
이 경우 그 내용을 공지합니다.
제 13 조 (홈페이지 저작권)
① NDSL에서 제공하는 모든 저작물의 저작권은 원저작자에게 있으며, KISTI는 복제/배포/전송권을 확보하고
있습니다.
② NDSL에서 제공하는 콘텐츠를 상업적 및 기타 영리목적으로 복제/배포/전송할 경우 사전에 KISTI의 허락을
받아야 합니다.
③ NDSL에서 제공하는 콘텐츠를 보도, 비평, 교육, 연구 등을 위하여 정당한 범위 안에서 공정한 관행에
합치되게 인용할 수 있습니다.
④ NDSL에서 제공하는 콘텐츠를 무단 복제, 전송, 배포 기타 저작권법에 위반되는 방법으로 이용할 경우
저작권법 제136조에 따라 5년 이하의 징역 또는 5천만 원 이하의 벌금에 처해질 수 있습니다.
제 14 조 (유료서비스)
① 당 사이트 및 협력기관이 정한 유료서비스(원문복사 등)는 별도로 정해진 바에 따르며, 변경사항은 시행 전에
당 사이트 홈페이지를 통하여 회원에게 공지합니다.
② 유료서비스를 이용하려는 회원은 정해진 요금체계에 따라 요금을 납부해야 합니다.
제 5 장 계약 해지 및 이용 제한
제 15 조 (계약 해지)
회원이 이용계약을 해지하고자 하는 때에는 [가입해지] 메뉴를 이용해 직접 해지해야 합니다.
제 16 조 (서비스 이용제한)
① 당 사이트는 회원이 서비스 이용내용에 있어서 본 약관 제 11조 내용을 위반하거나, 다음 각 호에 해당하는
경우 서비스 이용을 제한할 수 있습니다.
- 2년 이상 서비스를 이용한 적이 없는 경우
- 기타 정상적인 서비스 운영에 방해가 될 경우
② 상기 이용제한 규정에 따라 서비스를 이용하는 회원에게 서비스 이용에 대하여 별도 공지 없이 서비스 이용의
일시정지, 이용계약 해지 할 수 있습니다.
제 17 조 (전자우편주소 수집 금지)
회원은 전자우편주소 추출기 등을 이용하여 전자우편주소를 수집 또는 제3자에게 제공할 수 없습니다.
제 6 장 손해배상 및 기타사항
제 18 조 (손해배상)
당 사이트는 무료로 제공되는 서비스와 관련하여 회원에게 어떠한 손해가 발생하더라도 당 사이트가 고의 또는 과실로 인한 손해발생을 제외하고는 이에 대하여 책임을 부담하지 아니합니다.
제 19 조 (관할 법원)
서비스 이용으로 발생한 분쟁에 대해 소송이 제기되는 경우 민사 소송법상의 관할 법원에 제기합니다.
[부 칙]
1. (시행일) 이 약관은 2016년 9월 5일부터 적용되며, 종전 약관은 본 약관으로 대체되며, 개정된 약관의 적용일 이전 가입자도 개정된 약관의 적용을 받습니다.