• Title/Summary/Keyword: Reproduction experiments

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A Study on Setting the Minimum and Maximum Distances for Distance Attenuation in MPEG-I Immersive Audio

  • Lee, Yong Ju;Yoo Jae-hyoun;Jang, Daeyoung;Kang, Kyeongok;Lee, Taejin
    • Journal of Broadcast Engineering
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    • v.27 no.7
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    • pp.974-984
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    • 2022
  • In this paper, we introduce the minimum and maximum distance setting methods used in geometric distance attenuation processing, which is one of spatial sound reproduction methods. In general, sound attenuation by distance is inversely proportional to distance, that is 1/r law, but when the relative distance between the user and the audio object is very short or long, exceptional processing might be performed by setting the minimum distance or the maximum distance. While MPEG-I Immersive Audio's RM0 uses fixed values for the minimum and maximum distances, this study proposes effective methods for setting the distances considering the signal gain of an audio object. Proposed methods were verified through simulation of the proposed methods and experiments using RM0 renderer.

Prediction of Poor Contact by Analysis of Electrical Signal and Thermal Characteristics (전기적 신호와 열적특성 분석에 의한 접촉불량 예측)

  • Lee, Heung-Su;Kim, Doo-Hyun;Kim, Sung-Chul;Kim, Yoon-Bok
    • Journal of the Korean Society of Safety
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    • v.27 no.3
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    • pp.36-41
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    • 2012
  • Electrical Connections often cause fires due to poor contact. Occurrence rate of these fires tends to increase annually. The reason why poor contacts occur is often because it is the low mechanical pressure at the contact points. A typical connection method using mechanical pressure is a screw terminal type. This study reviewed these poor contact cases in the screw terminals. In order to get reproduction of such cases, two types of experiments were conducted. the first one was conducted under the normal contact condition, and the other one was conducted under the poor contact condition that screw terminal of breaker was loosen and did not meet the requirements of toque value. In both types of experiments, compulsory vibration was adopted as a variable to aggravate poor contacts. Each of various current values(4.5A, 9.0A, 13.5A) is input. In these experiments, relationships of a contact, electrical signal such as current and electric pulse by ZCT and thermal characteristics according to vibration effect are analyzed. The suggested data and results in this study provide the useful resources helping to investigate fires due to poor contact, and they develop the detector for poor contact and finally reduce the electrical fire occurrence rate.

Reproductive Biotechnologies for Improvement of Buffalo: The Current Status

  • Purohit, G.N.;Duggal, G.P.;Dadarwal, D.;Kumar, Dinesh;Yadav, R.C.;Vyas, S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.7
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    • pp.1071-1086
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    • 2003
  • Reproductive biotechnologies continue to be developed for genetic improvement of both river and swamp buffalo. Although artificial insemination using frozen semen emerged some decades back, there are still considerable limitations. The major problem appears to be the lack of efficient methods for estrus detection and timely insemination. Controlled breeding experiments in the buffalo had been limited and similar to those applied in cattle. Studies on multiple ovulation and embryo transfer are essentially a replica of those in cattle, however with inherent problems such as lower number of primordial follicles on the buffalo ovary, poor fertility and seasonality of reproduction, lower population of antral follicles at all stages of the estrous cycle, poor endocrine status and a high incidence of deep atresia in ovarian follicles, the response in terms of transferable embryo recovery has remained low with 0.51 to 3.0 per donor and pregnancy rates between 15 to 30%. In vitro production of buffalo embryos is a valid alternative to recovery of embryos by superovulation. This aspect received considerable attention during the past decade, however the proportion of embryos that develops to the blastocyst stage is still around 25-30% and hence the in vitro culture procedures need substantial improvement. Embryo cryopreservation procedures for direct transfer post thaw need to be developed for bubaline embryos. Nuclear transfer and embryo cloning is a technique that has received attention in various species during recent years and can be of immense value in buffaloes as they have a low rate of embryo recoveries by both in vitro and in vivo procedures. Gender pre-selection, genome analysis, gene mapping and gene transfer are a few of the techniques that have been studied to a limited extent during recent years and are likely to be included in future studies on buffaloes. Very recently, reproductive biotechnologies have been applied to feral buffaloes as well, but the results obtained so far are modest. When fully exploited they can play an important role in the preservation of endangered species.

Studies on in vitro Maturation and Fertilization of Porcine Follicular Oocytes (돼지 난포란의 체외성숙 및 수정에 관한 연구)

  • 김상근;이만휘;이명헌;신용호
    • Korean Journal of Animal Reproduction
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    • v.14 no.1
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    • pp.23-30
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    • 1990
  • These studies were carried out to investigate the effects of fetal calf serum(FCS), estrous porcine serum(EPS), porcine follicular fluid(PFF), hormone and matured cumulus cell(MCC) on in vitro maturation and fertilization of porcine follicular oocytes. The ovaries and testes were obtianed from slaughtered Landrace sow and boars, respectively. The follicular oocytes surrounded with cumulus cells were recovered by aspirating follicular fluid from the visible follicles of diameter 3~5 mm and the semen were prepared from boar's epididymal cauda. The follicular oocytes were cultured in TCM-199 medium containing hormones, FCS, EPS, PFF and MCC for 48hrs. in a incubator with 5% CO2 in air at 36$^{\circ}C$ and then matured oocytes were again cultured for 18~20 hrs. with $1.5\times$106/ml motile capacitated sperm in the modified Tyroide solution containing 100$\mu\textrm{g}$/ml of heparin. The results obtained in these experiments were summarized as follows : 1. The maturation and fertilization rate of the follicular oocytes, cultured in the TCM-199 medium supplemented with 10% FCS and PMSG+HCG were 55.6~64.5% and 33.3~37.1%, respectively. 2. The maturation and fertilization rate of the follicular oocytes cultured in the TCM-199 medium supplemented with 20% EPS and PMSG+HCG were 50.0~55.0% and 30.3~33.3%, respectively. 3. The maturation rate(59.0~64.2%) and fertilization rate(34.8~39.3%) of follicular oocytes cultured in TCM-199 medium supplemented 20% FCS and 50% PFF were higher than those of follicular oocytes cultured in TCM-199 medium supplemented with 5%, 10% and 15% FCS and 10% and 50% PFF. 4. The maturation rate(60.0%) and fertilization rate(40.0%) of follicular oocytes cultured in TCM-199 medium supplemented with 20% FCS and granulosa cell (1$\times$106/ml) were significantly higher than those of fiollicular oocytes cultured in TCM-199 medium supplemented with 5%, 10% and 15% FCS and granulosa cell.

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Studies on In Vitro Maturation of Pig Follicular Oocytes (돼지 난포란의 체외성숙에 관한 연구)

  • 김창근;정영채;이명식;윤종택;방명걸;정길생
    • Korean Journal of Animal Reproduction
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    • v.14 no.1
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    • pp.84-91
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    • 1990
  • Experiments were disigned to define and optimize efficiency of a system whereby pig follicular oocytes could be matured and fertil ized in vitro. The pig oocytes removed from 1- 2 mm and 3-7 mm follicles were cultured in vitro in the mKRB(-BSA) solution containing estrous sow serum (ESS), FCS or dialyzed pig follicular fluid for 24 to 48 hr at 37$^{\circ}C$. The oocytes matured in vitro were evaluated after epididymal spermatozoa-oocyte incubation for 24 hr for pronucleus formation. 50-60% of the oocytes reached metaphase II during 36 to 48 hr of culture. There was no differernce in oocyte matura¬tion between two groups of follicular size but meiosis was slightly faster in the 3-7 mm follicular oocytes. The oocytes matured in mKRB (-BSA) plus 5% ESS, 15% FCS or dialyzed follicular fraction showed slightly higher maturation rates than the control mKRB. in vitro fertilization, pronucleus formation, tended to be increased when mKRBi-BSA) plus 5% ESS or 15% FCS was used for oocyte maturation and in vivo -capacitated spermatozoa were inseminated, respectively. It is concluded that ESS, FCS and dialyzed pig follicular fluid may be effective factors for in vitro maturation and fertilization of pig follicular oocytes.

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Expression of E. coli LacZ Gene in Bovine Morular or Blastocysts after Microinjection of Retrovirus Vector-Producing Cells into the Perivitelline Space of One-to Four-Cell Embryos (체외생산된 우유정란으로부터 형질전환우의 생산성 제고를 위한 Retrovirus Vector System의 이용성 검토)

  • 김태완;박세필
    • Korean Journal of Animal Reproduction
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    • v.19 no.1
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    • pp.35-41
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    • 1995
  • In this study, we have tested whether the retrovirus vector system is applicable in transgenic cattle production. To overcome low infectivity of currently available retrovirus vector system we have directly microinjected retrovirus-producing cells into the perivitelline space of the day 1.5 embryos. The virus-producing cell line was designed to release replication-defective retrovirus encapsidated with Gibbon ape leukemia virus (GaLV) envelope protein. E. coli LacZ gene was used as a marker gene to facilitate evaluation of the transgene expression and X-gal staining at morula or blastocyst stage resulted in expression of E. coli LacZ gene The results in these experiments were summarized as follows : 1. The lowest concentration of polybrene necessary for efficient virus infection was Sf' g/ml. 2. Development rate from day 1.5 embryos microinjected with virus-producing cells to the morulae /blastocysts was 29%. 3. 21% of the morulae /blastocysts were LacZ+. 4. There was no evidence that the retrovirus-producing cells used in this study produced replication-competent retrovirus.

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Effect of Conditioned Medium of Human Endothelial Cell Line(tHUE-2 cell) on In Vitro Development of Mouse 1-cell Embryos In Vitro Fertilized (체내 수정된 Mouse 1-세포배의 체외발생에 미치는 혈관내피세포주(tHUE-2세포) 배양액의 영향)

  • ;;;Y. Mitsui
    • Korean Journal of Animal Reproduction
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    • v.19 no.2
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    • pp.81-88
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    • 1995
  • Culture medium (ASF-301) of tHUE-2 cell, human endothelial cell line, and culture medium of these cells (conditioned medium : CM) which affect embryonic development of in vivo fertilized 1-cell embryos of mouse were examined. Two-cell stage block of mouse embryos was overicomed in ASF-301 and CM without EDTA, which usually added in basic medium (modified Whitten Medium: MWM, control) to overcome the 2-cell stage block. The developmental rates of embryos to the blastocyst stage were significantly increased in MWM containing 12.5% of growth factors added to ASF-301 (10mg/ $\ell$ transferrin, 1mg/$\ell$ insulin, 0.01mg/$\ell$ EGF) than those of 100% addition and control, 78.0% vs 20.8 and 52.3%, respectively (P<0.05), but the growth factors was not affected the hatching rate of blastocyst. Using ASF-301 or CM which was not treated, embryonic development into the blastocyst and hatched blastocyst stages were not affected. However, proportions of embryonic development into the blastocyst and hatched blastocyst stages were significantly higher in dilution (ASF-301 1:10; CM 1:3~1:6) than those in control (P,0.05). In ASF-301 dialyzed M.W.<10000 dialysis membrane, the developmental rate upto the hatched blastocyst stage was significantly increased, compared to ASF-301 which was not dialyzed (P<0.05), and hatching rate of blastocyst of these group was singnificantly increased than those in MWM (P<0.05). Compared to CM which was not dialyzed, however, in dialyzed CM was significantly decreased, compared to untreated CM (P<0.05), especially any hatched blastocyst was not appeared. As a result of these experiments indicated that a kind or porper treatment such as a dilution of complex synthetic cell culture medium and conditioned medium, and that a optimal concentration of growth factors are usuful for embryo cultrue in vitro.

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Applicability of Steel Slag Aggregate for Artificial Armor Unit (제강슬래그 골재의 소파블록 적용성 평가)

  • Yang Eun-Ik;Lee Kwang-Gyo;Han Sang-Hun
    • Journal of the Korea Concrete Institute
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    • v.16 no.5 s.83
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    • pp.591-596
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    • 2004
  • In order to evaluate the applicability of steel slag aggregates for tetrapod concrete, the properties of concrete as structural material were investigated. The biochemical research of marine concrete using steel slag aggregates was also carried out. The tested concrete properties are slump, ai content, compressive strength, splitting tensile strength, elastic modulus, carbonation, hydration heat, freezing and thawing, sulfate attack, drying shrinkage, etc. The biochemical experiments are carried to research the propagation and reproduction of seaweeds and survival of bottom dwelling species. According to this experiment results, the steel slag aggregate content did not have a significant effect on compressive strength, splitting tensile strength and elastic modulus. The durability of concrete was not influenced by the steel slag aggregate content. From the biochemical research, steel slag aggregate can be evaluated as the material that is ideally suited for promoting propagation and reproduction of seaweeds and sessile benthos.

Studies on Artificial Control of Parturition in Korean Native Goats I. The Effect of Prostaglandin $F_2\alpha$ to Induce Parturition (한국 재래산양 분만의 인위적 조절에 관한 연구 I. Prostaglandin $F_2\alpha$ 투여에 의한 분만유기 효과)

  • 윤창현;민관식;장규태;오석두
    • Korean Journal of Animal Reproduction
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    • v.15 no.2
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    • pp.109-115
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    • 1991
  • This experiment was conducted to find out the time to farrowing induction after PGF2$\alpha$ treatment, the rate of farrowing induction, the effect of kids born by the induced farrowing on birth weight and development with study on artificial control of parturition in Korean native goats. A total of 24 pluriparous goats were offered for this experiment. The animals were divided into 4 goats per treatment by administration time(142, 145 or 148 day of pregnancy) and dosage (5 or 7.5mg). The results obtained in this experiments were as follows : 1. The effect of synchronization of estrus was induced 23 goats(95.1%), 16 goats(66.6%) in the 1st treatment and 7 goats(28.5%) in the 2nd treatment PGF2$\alpha$ and exhibited estrus at a mean interval of 75$\pm$5 hours after PGF2$\alpha$ injection. 2. The time to farrowing induction after PGF2$\alpha$ treatment on day 145 or 148 was significantly(P<0.01) shorter than that of the 5mg treatment, but there was no significant difference(P>0.01). 3. Parturition was induced in all goats(100%) treated 5 or 7.5mg of PGF2$\alpha$ on day 148 and 7.5mg of PGF2$\alpha$ on day 145, but was induced 75% in treatment with 5mg of PGF2$\alpha$ on day 145 and 5 or 7.5mg of F2$\alpha$ on day 142. 4. The birth weight and development of kids induced farrowing was heaviest (P<0.01) on days 148 among treatment, but there was no significant difference in dosage.

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Studies on in vitro Development of Blastomeres Separated from Mouse Embryos (생쥐배 분할구의 in vitro 발달에 관한 연구)

  • 정덕수;이상진;정길생
    • Korean Journal of Animal Reproduction
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    • v.12 no.3
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    • pp.132-140
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    • 1988
  • These experiments were carried out to examine the development capacity of mouse blastomers separated from 2 to 8-cell stage mouse embryos. The female ICR and C3H mice were subjected to supervolution by intraperitoneal injection of PMSG and HCG and then mated with males of the same strain. Embryos were flushed from oviducts and uteri on a proper time after injection of HCG. After removal of zona pellucida with 0.5% pronase, each embryos were separated into 1/2, 1/4, 2/4, 1/8, 2/8 and 4/8 embryos by pipetting or a fine glass needle in Ca2+$.$Mg-2+ free Hoppe& Pitts medium containing 0.02% EDTA. Splitted embryos were cultured in Hoppe & Pitts medium for 48h to 72h. The embryos developed to blastocyst were transferred to recipients on 2 or 3 days of pseudopregnancy. On the other hand, a monozygotic pairs of 1/2 embryos developed to blastocyst after 48h in vitro culture were transferred to recipients on 2 days of pseudopregnancy or pregnancy. The results obtained were summarized as follows. 1. Success rates of separation of blastomeres from 2-, 4- and 8-cell embryos were 91.7%, 68.5-92.4% and 60.8-90.6%, respectively. 2. Development rates of various type of blastomeres to blastocyst after 72h in vitro culture were ranged 64.7-87.1%. 3. Blastocysts obtained after 48h in vitro culture were transferred to recipients on 2 or 3 days of pseudopregnancy. The production rates of live fetuses after transfer on 2 days, only 1/2, 2/4 and 4/8 embryos, were 13.2%, 13.5% and 17.2%, respectively and those of embryos transferred on 3 days were 11.8%, 9.6% and 11.5%, respectively. However, the production rates of live fetuses 1/2 embryos following 72h in vitro culture and transfer to recipients on 2 or 3 days of pseudopregnancy were 7.7% and 12.5%, respectively. 4. From 29 and 31 pairs of 1/2 embryos transferred to recipients on 2 days of pseudopregnancy or pregnancy, 4 sets of monozygotic twins were produced from only pregnant recipients.

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