• Title/Summary/Keyword: Pure sciences

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Effects of Sire Breed on the Subsequent Reproductive Performances of Landrace Sows

  • Huang, Y.H.;Yang, T.S.;Lee, Y.P.;Roan, S.W.;Liu, S.H.
    • Asian-Australasian Journal of Animal Sciences
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    • v.16 no.4
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    • pp.489-493
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    • 2003
  • Reproductive traits of sows are determined chiefly by the genetic background of the dam herself. Whether the breed of the serviced boars also contributes is not yet clear. A total of 8,946 litters of Landrace (L) sows from 68 farms were examined. Of these, 876, 1,260, and 6,810 litters were produced from natural mating with L, Yorkshire (Y), and Duroc (D) breeds, respectively. The birth litter size (BLS), weaning litter size (WLS), live born piglets (LBP), and survival rate % (SR), of every litter were recorded. A general linear-model procedure was followed to estimate the effects of boars' breed (B), parity (P) and B${\times}$P interaction on the reproductive traits of the sows. Results show that BLS, WLS, and LBP were all significantly (p<0.001) affected by B and P. SR% was significantly influenced by B but not by P. L sows crossbred with Y or purebred with L produced litters with higher BLS, WLS, and LBP values than those bred with D. Pure L breeding yielded litters with lower SR% than did crossbreeding with D, while the difference between SR% due to LY and that due to LD crossbreeding was not significant. The interaction of B with P was significant with respect to BLS, WLS, and LBP (p<0.001), but not SR%. No significant B effect on reproductive traits was measured in sows at their first parity; but at latter parities, LL or LY produced litters with similarly high BLS, WLS and LBP, which values were all significantly greater than those of LD litters. The breed of boar evidently affected the subsequent reproductive performance of L sows and this effect may be further manipulated by the parity effect. Breed differences in semen quality and the success of fetus development with different interactions of the genetic background with the uterus function of the sow that may contribute to these effects are discussed.

Study on the Performance of Different Genotypes of Ducks under Village Condition

  • Jalil, M.A.;Ali, A.;Begum, J.;Islam, M.R.
    • Asian-Australasian Journal of Animal Sciences
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    • v.10 no.2
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    • pp.192-195
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    • 1997
  • Thirty adults Desi and Khaki Campbell ducks were distributed to 6 farmers of Chakcharpur village of Mymensingh district. These ducks were subjected 3 types of mating e.g. Desi ${\times}$ Desi, Khaki Campbell ${\times}$ Khaki Campbell and Khaki Campbell ${\times}$ Desi-having 10 ducks (male : female = 1 : 4) in each mating group. Each mating group was then divided into two having 5 ducks(male : female = 1 : 4) and distributed to 2 farmers. After collecting eggs from each mating category, these were hatched by broody hens from which a total of 90 day old ducklings, 30 from each genotype were raised from birth to 90 days after the onest of laying. Although the weight of the day old chicks were similar in all genotypes (40-43 g), body weight was the highest (p <0.01) for Khaki Campbell ${\times}$ Desi (1,543) before the onset of laying followed by Khaki Campbell (1,552 g) and Desi (1,448 g) ducks. Khaki Campbell attained maturity at an earlier (p < 0.01) age (147 days) followed by Khaki Campbell ${\times}$ Desi, (154 days) and Desi (161 days) ducks. Khaki Campbell laid maximum (p < 0.01) number of eggs (46) compared to Khaki Campbell ${\times}$ Desi, (30) and Desi (18) ducks 90 days after the onset of laying. However, eggs were heavier (p < 0.01) in Desi (61.9) ducks compared to other genotypes. Fertility and hatchability were also higher in Desi ducks than the other two genotypes. Mortality was also lover in Desi ducks (3.33%) followed by Khaki Campbell ${\times}$ Desi (6.66%) and Khaki Campbell (16.66%) ducks. The results presented here indicated the superiority of Desi ducks over the other two genotypes with respect to egg weight, fertility, hatchability and mortality under village condition. Pure and crossbreds, on the other hand, were heavier at sexual maturity at relatively younger age and laid more eggs.

Effects of Ensiling Alfalfa with Whole-crop Maize on the Chemical Composition and Nutritive Value of Silage Mixtures

  • Ozturk, Durmus;Kizilsimsek, Mustafa;Kamalak, Adem;Canbolat, Onder;Ozkan, Cagri Ozgur
    • Asian-Australasian Journal of Animal Sciences
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    • v.19 no.4
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    • pp.526-532
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    • 2006
  • The aim of this study was to evaluate the chemical composition, in vitro DM degradability, ME and OMD of alfalfa-maize silage mixtures in comparison to pure maize and alfalfa silages, and to test the existence of associative effects of ensiling alfalfa forage with whole-crop maize using the in vitro gas production technique. Ensiling alfalfa with whole-crop maize had a significant (p<0.001) effect on chemical composition, pH, in vitro DM degradability, OMD and estimated ME values of mixtures. DM content of the resultant silages significantly increased with increasing proportion of whole-crop maize in the mixtures, whereas the pH value, crude protein (CP), acid detergent fibre (ADF) and ash contents of mixtures decreased due to the dilution effect of whole-crop maize which was low in CP, ADF and ash. The pH values of all alfalfa-maize silage mixtures were at the desired level for quality silage. Gas production of alfalfa-maize silage mixtures at all incubation times except 12 h increased with increasing proportion of whole-crop maize. When alfalfa was mixed with whole-crop maize in the ratio 40:60, ME and OMD values were significantly (p<0.001) higher than other silages. Maximum gas production ($A_{gas}$) ranged from 65.7 to 78.1 with alfalfa silage showing the lowest maximum gas production. The results obtained in this study clearly showed that maximum gas production increased with increased percentage of whole-crop maize in the silage mixtures (r = 0.940, p<0.001). It was concluded that ensiling alfalfa with whole-crop maize improved the pH, OMD and ME values. However, trials with animals are required to see how these differences in silage mixtures affect animal performance.

A Design of Wideband, High Efficiency Power Amplifier using LDMOS (LDMOS를 이용한 광대역, 고효율 전력증폭기의 설계)

  • Choi, Sang-Il;Lee, Sang-Rok;Rhee, Young-Chul
    • The Journal of the Korea institute of electronic communication sciences
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    • v.10 no.1
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    • pp.13-20
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    • 2015
  • Existing LDMOS power amplifier that used class-AB and doherty system shows 55% of efficiency in 60MHz narrow band. Because RRH has been applied to power amplifier at base station. It is required that over 100MHz expanded band and more than 60% high efficiency power amplifier. In this paper we designed class-J power amplifier using LDMOS FET which has over 60% high efficiency characteristic in 200MHz. The output matching circuit of designed class-J power amplifier has been optimized to contain pure reactance at second harmonic load and has low quality factor Q. As a measurement result of the amplifier, when we input continuous wave signal, we checked 62~70% of power added efficiency(PAE) in 2.06~2.2GHz including WCDMA frequency as a 10W class-J power amplifier.

Immunogenicity of Recombinant Human Erythropoietin: Clinical Cases, Causes and Assays

  • Heo, Tae-Hwe;Kim, Young-Kwon;Yang, Seung-Ju;Cho, Hyun-Jeong;Kim, Sung-Jo
    • Biomedical Science Letters
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    • v.15 no.2
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    • pp.161-166
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    • 2009
  • Human erythropoietin(EPO) is a glycoprotein that enhances red blood cell production by stimulating proliferation and differentiation of erythroid progenitor cells in the bone marrow. Patients with chronic kidney disease(CKD) suffer from anemia caused by reduced production of EPO in the kidney. Recombinant human EPO protein has been used successfully for the treatment of anemia associated with CKD. Recently, attention has been paid to the development of side effect of EPO, pure red cell aplasia(PRCA), in some patients with CKD. PRCA is a rare disorder of erythropoiesis that leads to a severe anemia due to an almost complete cessation of red blood cell production. EPO-related PRCA is caused by the production of EPO-neutralizing antibodies(Abs) that eliminate the biological activity of EPO as well as endogenous EPO in patients undergoing therapy. Since 1988, almost 200 cases worldwide have been reported with Ab-positive PRCA after receiving EPO therapeutics. The underlying mechanisms of the breaking of immune tolerance to self-EPO have been investigated. Modification of formulation, organic compounds of container closures, and route of administration has been suggested for the possible mechanism of increased immunogenicity of EPO. A number of assays have been used to detect Abs specific to EPO. These assays are generally grouped into two major categories: binding Ab assays and neutralizing Ab assays(bioassays). There are several types of binding Ab assays, including radioimmunoprecipitation assay, enzyme-linked immunosorbent assay, and the BIAcore biosensor assay. In vitro cell-based bioassays have been utilized for the detection of neutralizing Abs. Finally, the recent experience with anti-EPO Abs may have considerable implications for the future development and approval of EPO preparations. Also, considering that millions of patients are being treated with EPO, clinicians need to be aware of signs and consequences of this rare but severe clinical case.

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ACCELERATION OF COSMIC RAYS AT LARGE SCALE COSMIC SHOCKS IN THE UNIVERSE

  • KANG HYESUNG;JONES T. W.
    • Journal of The Korean Astronomical Society
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    • v.35 no.4
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    • pp.159-174
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    • 2002
  • Cosmological hydrodynamic simulations of large scale structure in the universe have shown that accretion shocks and merger shocks form due to flow motions associated with the gravitational collapse of nonlinear structures. Estimated speed and curvature radius of these shocks could be as large as a few 1000 km/s and several Mpc, respectively. According to the diffusive shock acceleration theory, populations of cosmic-ray particles can be injected and accelerated to very high energy by astrophysical shocks in tenuous plasmas. In order to explore the cosmic ray acceleration at the cosmic shocks, we have performed nonlinear numerical simulations of cosmic ray (CR) modified shocks with the newly developed CRASH (Cosmic Ray Amr SHock) numerical code. We adopted the Bohm diffusion model for CRs, based on the hypothesis that strong Alfven waves are self-generated by streaming CRs. The shock formation simulation includes a plasma-physics-based 'injection' model that transfers a small proportion of the thermal proton flux through the shock into low energy CRs for acceleration there. We found that, for strong accretion shocks, CRs can absorb most of shock kinetic energy and the accretion shock speed is reduced up to $20\%$, compared to pure gas dynamic shocks. For merger shocks with small Mach numbers, however, the energy transfer to CRs is only about $10-20\%$ with an associated CR particle fraction of $10^{-3}$. Nonlinear feedback due to the CR pressure is insignificant in the latter shocks. Although detailed results depend on models for the particle diffusion and injection, these calculations show that cosmic shocks in large scale structure could provide acceleration sites of extragalactic cosmic rays of the highest energy.

A size analysis in obstructive sleep apnea patients (폐쇄성 수면무호흡 환자의 안면 및 혀의 크기에 대한 연구)

  • Pae, Eung-Kwon;Lowe, Alan A.;Park, Young-Chel
    • The korean journal of orthodontics
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    • v.27 no.6 s.65
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    • pp.865-870
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    • 1997
  • The submental region in patients with Obstructive Sleep Apnea (OSA) is Perceived to be larger than normal. Therefore, neck thickness has become a variable routinely measured during clinical screening of OSA subjects. In general, OSA Patients are believed to have a large tongue and a narrow airway. To test if OSA patients have a larger face and tongue than non-apneics, eighty pairs of upright and supine cephalograms were obtained from four groups of subjects subclassified in accordance with severity. The sum of distances between pairs of landmarks was calculated for each subjects and employed as a pure size variable for the face and tongue. Only tongue size becomes larger in accordance with apnea severity in both body positions (P<.01). Tongue size reflects apnea severity, yet it Provides only a small fraction of the explanation with regard to apnea severity. We conclude that size may be one factor of many which are significantly related to OSA severity.

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Instrumentation of a Thermal-Optical Carbon Analyzer and Its Sensitivity in Organic and Elemental Carbon Determination to Analysis Protocols

  • Lim, Ho-Jin;Sung, Su-Hwan;Yi, Sung-Sin;Park, Jun-Hyun
    • Journal of Environmental Science International
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    • v.21 no.1
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    • pp.1-9
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    • 2012
  • A thermal-optical transmittance carbon analyzer has been developed to determine particulate organic (OC) and elemental (EC) carbon. Several analysis factors affecting the sensitivity of OC and EC determination were investigated for the carbon analyzer. Although total carbon (TC) is usually consistent in the determination, OC and EC split is sensitive to adopted analysis protocol. In this study the maximum temperature in oxygen-free He in the analysis was examined as a main cause of the uncertainty. Prior to the sensitivity analysis consistency in OC-EC determination of the carbon analyzer and the uniformity of carbonaceous aerosol loading on a sampled filter were checked to be in acceptable range. EC/TC ratios were slightly decreased with increasing the maximum temperature between $550-800^{\circ}C$. For the increase of maximum temperature from $500^{\circ}C$ to $800^{\circ}C$, the EC/TC ratio was lowered by 4.65-5.61% for TC loading of 13-44 ${\mu}g/cm^2$ with more decrease at higher loading. OC and EC determination was not influenced by trace amount of oxygen in pure He (>99.999%), which is typically used in OC and EC analysis. The facing of sample loaded surface to incident laser beam showed negligible influence in the OC-EC split, but it caused elevated PC fraction in OC for forward facing relative to backward facing.

Synthesis of graphene and its application to thermal and surface modification (그래핀의 합성과 열전도 및 표면 특성 개선 활용)

  • Kim, Yong-You;Jang, Hee-Jin;Choi, Byung-Sang
    • The Journal of the Korea institute of electronic communication sciences
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    • v.8 no.4
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    • pp.549-554
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    • 2013
  • With the synthesis of graphene on Cu using CVD, it was tried to show the behavior of graphene growth depending on the size and orientation of Cu grain. It was found out that even under the same temperature and pressure the use of different gases influences on the diffusion rate of Cu. As compared to Ar gas, Cu grain growing bigger under $H_2$ and $CH_4$ was resulted in bigger graphene grain. Corrosion resistance was evaluated by potentiodynamic polarization test in room temperature and found out that the graphene on Cu was more stable in order of 10 than pure Cu due to the chemical stability of graphene. The future work of this research will focus on the synthesis of graphene having no defects including grain boundaries, and its engineering use.

Comparison and Correlation Analysis of Different Swine Breeds Meat Quality

  • Li, Yunxiao;Cabling, Meriam M.;Kang, H.S.;Kim, T.S.;Yeom, S.C.;Sohn, Y.G.;Kim, S.H.;Nam, K.C.;Seo, K.S.
    • Asian-Australasian Journal of Animal Sciences
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    • v.26 no.7
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    • pp.905-910
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    • 2013
  • This study was performed to determine the influence of pig breed and gender on the ultimate pH and physicochemical properties of pork. The correlations between pH and pork quality traits directly related to carcass grade, and consumer's preference were also evaluated. The pH and meat grading scores for cold carcasses of 215 purebred pigs (Duroc, Landrace, and Yorkshire) from four different farms were obtained. Meat quality parameters of the pork loin were analyzed. Duroc and female animals were more affected compared to other breeds and male pigs. Duroc animals had the highest ultimate pH, carcass back fat thickness, marbling scores, yellowness, and fat content (p<0.05). Landrace pigs had the highest color lightness and cooking loss values (p<0.05). Among all trait parameters, marbling scores showed the highest significant differences when evaluating the impact of breed and gender on meat quality characteristics (p<0.001). Ultimate pH was positively correlated with carcass weight (0.20), back fat thickness (0.19), marbling score (0.17), and color score (0.16) while negatively correlated with cooking loss (-0.24) and shear force (-0.20). Therefore, pork samples with lower ultimate pH had lower cooking loss, higher lightness, and higher shear force values irrespective of breed.