• Title/Summary/Keyword: 유전 흡수

Search Result 214, Processing Time 0.031 seconds

Optical Absorption and Polarogram of Macrocyclic Nickel (II) Complexes in Polar Solvents (극성용매에서 거대고리 Ni (II) 착물의 광흡수와 폴라로그램)

  • Park Yuj-Chul;Jong-Chul Byun
    • Journal of the Korean Chemical Society
    • /
    • v.31 no.2
    • /
    • pp.168-177
    • /
    • 1987
  • The equilibria of chemical reaction between $\alpha$-Ni(rac-[14]-decane)$^{2+}$ and polar solvents(L; ANT, MFA, DMSO, DMF, and DMA) have been investigated by the spectrophotometric method at $25^{\circ}C$. (The equilibrium constants($K_1$) of) the first step in ANT, MFA, DMSO, DMF, and DMA were 31.0, 27.5, 21.3 15.9, and 6.4, respectively. The smallness of equilibrium constants ($K_2$) of the second step compared with $K_1$, was observed. $\alpha$-Ni(rac-[14]-dacane)$^{2+}$ + L $\leftrightharpoons$ [$\alpha$-Ni(rac-[14]-decane){\cdot}L]$^{2+}$ : $K_1$.[$\alpha$-Ni(rac-[14]-decane){\cdot}L)$^{2+}$+ L $\leftrightharpoons$ [$\alpha$-Ni(rac-[14]-decane){\cdot}$L_2$)$^{2+}$ :$K_2$. The relationship between d-d absorption energy and half-wave potential of complex ions at ACT was considered. Macrocyclic ligands increasing d-d transition energy caused half-wave potentials of Ni(II)-macrocycle to be shifted more positively. The half-wave potentials for Ni(rac-1[14]7-diene)$^{2+}$, Ni(meso-1[14]7-diene)$^{2+}$, Ni(1[14]4-diene)$^{2+}$, $\alpha$-Ni(rac-[14]-decane)$^{2+}$, ${\beta}-Ni(rac-[14]-decane)$^{2+}$, and Ni(meso-[14]-decane)$^{2+}$ reductions were -1.419, -1.431, -1.450, -1.473, and -1.480 (V vs. SCE), respectively. The d-d transition energies ($\nu_{max},\;cm^{-1}$) of the Ni(meso-[14]-decane)$^{2+}$ isomer were discussed with the dielectric constant (${\varepsilon}/{\varepsilon}_0$) of the various solvents, $\nu_{max}(cm^{-1})$ increased with increasing ${\varepsilon}/{\varepsilon}_0$.

  • PDF

Biosynthesis of the extracellular enzymes in de novo during the differentiation of Aspergillus niger (검정곰팡이의 형태분화에 따른 세포외성효소의 신생적생합성에 관한 연구)

  • Kim, Jong-Hyup
    • The Korean Journal of Mycology
    • /
    • v.6 no.2
    • /
    • pp.1-10
    • /
    • 1978
  • In de novo biosynthesis of the extracellulor enzymes-proteinsaes, alpha and gluc-amylases during the synchronized differentiation of Aspergillus niger in submerged culture and surface liquid culture were investigated. Gluc-amylase was synthesized in the stage of presporulation in which phialide formation is involved. Proteinase was synthesized both in the stages of conidiophore formation and presporulation. Alpha-amylase was synthesized during presporulation and sporulation stages, the activity of enzyme lasted for seven days on surface liquid culture. It seemed that the synthesis was occured in de novo partly repressed by the catabolite, and its nature was found to be constitutive since it is produced in non-starch medium. Polyacrylamide gel electrophoresis have shown that presporulating and sporulating body produced diverse types of the proteins whereas the earlier stages of vegetative body showed simpler profiles. The uptake of C-14 uracil into RNA and C-14 glutamate into protein were shown to be vigorous in presporulating body rather than those in sporulating body. Coincidence of alpha-amylase biosynthesis in de novo and sporulation may be significant in the study of differentiation in which gene expression is involved.

  • PDF

Climatological Characteristics in the Variation of Soil temperature in Korea (우리나라 지중온도 변동의 기후학적 특성)

  • Kim Seoung-Ok;Suh Myoung-Seok;Kwak Chong-Heum
    • Journal of the Korean earth science society
    • /
    • v.26 no.1
    • /
    • pp.93-105
    • /
    • 2005
  • Climatological characteristics in the variation of soil temperatures in Korea were investigated using Korea Meterological Administration's observation data. And the impacts of soil moisture on the variation of soil temperature were examined using observed precipitation data. The climatological averages of soil temperatures are ranged from 14.4 to $15.0^{\circ}C$ regardless of depths. And they showed an latitudinal gradient with a warm temperature at the southern region and 'U' shape as in the air temperature with a high value along the coastal region. The relatively higher heat capacity and low conductivity of soil compared to those of the air resulted in the significant delay of the maximum and minimum date with depth. As a results, soil acts as a heat source during winter while a heat sink during summer. Global warming and urban heat island have increased the soil temperatures with an average rate $0.3\~0.5^{\circ}C/10-year$ as in the air temperature during last 30 years $(1973\~2002)$. However, the warming rate is maximized during spring contrary to the winter in the air temperature. The temporal variation of soil temperatures is strongly affected by that of soil moisture through an modification of the heat capacity and heat convection. In general, the increased soil moisture clearly decreased the temporal variations and increased the deep layer soil temperatures during cold season.

Evaluation of External Quality of Polished Barley (시판 소포장 보리쌀의 품위 평가)

  • Bae, Sook-Hyun;Kim, Hong-Sig;Jong, Seung-Keun
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.54 no.1
    • /
    • pp.124-133
    • /
    • 2009
  • Demand for the high quality barley with fibroid material and functional substances has been increasing in recent although the amount of barley consumption decreased drastically during the last two decades. But the limited information on quality of barley makes consumers hard when they purchase barley for their own consumption. Therefore, 51 brand barley, .i.e., 28 naked barley and 23 waxy barley from supermarkets and 10 polished barley from local markets were collected, and their external quality were analyzed to provide basic information on brand barley. Among 51 brand barley, 56% were 1kg package and 25% were 800 g package and there was no significant difference ($1{\pm}3.62\;g$) between printed and actual weighs. The weight of 1,000 grains of naked barley and waxy barley ranged $18.6{\sim}26.7\;g$ and $14.6{\sim}24.7\;g$, respectively. Thousand grain weight of 38% of naked barley ranged $20{\sim}22\;g$, while that of 43% of waxy barley ranged $18{\sim}20\;g$. The ratio of normal grains was 88% and 94% for naked barley and waxy barley, respectively, when separated with 1.7 mm sieve. Although 82% of brand barley products were free from foreign substances, in 18% of brand barley products, sands, pieces of cloth and wood, other kinds of grain and insect larvae were found, Average test weight of brand barleys was $843g{\cdot}L^{-1}$ with range of $805{\sim}917g{\cdot}L^{-1}$. Water content was less than 14% in 7.8% of barley products, while it was $14{\sim}15%$ in 62.7% of them. Average whiteness of brand barley was 31.06, while waxy barley had higher whiteness with 27.28 than naked barley with 34.16. Heated water uptake rate of milled naked barley and milled waxy barley were 215.4% and 231.7%, respectively, while expansion rate of milled naked barley and milled waxy barley were 379.7% and 401.6%, respectively. Barley from local markets were as good as brand barley products in 1,000 grain weight, ratio of normal grains, inclusion of foreign substances, test weight, water content, whiteness, water uptake rate, and expansion rate, but they showed higher ratio of foreign substances included.

Meteorological Constraints and Countermeasures in Rice Breeding -Breeding for cold tolerance- (기상재해와 수도육종상의 대책 - 내냉성품종육성방안-)

  • Mun-Hue Heu;Young-Soo Han
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.27 no.4
    • /
    • pp.371-384
    • /
    • 1982
  • Highly cold tolerant varieties are requested not only at high latitute cool area but also tropical high elevated areas, and the required tolerance is different from location to location. IRRI identified 6 different types of cold tolerance required in the world for breeding purpose; a) Hokkaido type, b) Suweon type, c) Taipei 1st season type, d) Taipei 2nd season type, e) Tropical alpine type and, f) Bangladesh type. The cold tolerance requested in Korea is more eargent in Tongil group cultivars and their required tolerance is the one such as the physiological activities at low temperature are as active as in Japonica group cultivars at least during young seedling stage and reproduction stage. With conventional Japonica cultivars, such cold tolerant characters are requested as short growth duration but stable basic vegetative growth, less sensitive to high temperature and less prolonged growth duration at low temperature. The methods screening for cold tolerance were developed rapidly after the Tongil cultivar was reliesed. The facilities of screening for cold tolerance, such as, low temperature incubator, cold water tank, growth cabinet, phytotron, cold water nursery in Chuncheon, breeding nursery located in Jinbu, Unbong and Youngduk, are well established. Foreign facilities such as, cold water tank with the rapid generation advancement facilities, cold nurseries located in Banaue, Kathmandu and Kashimir may be available for the screening of some limitted breeding materials. For the reference, screening methods applied at different growth stages in Japan are introduced. The component characters of cold tolerance are not well identified, but the varietal differences in a) germinability, b) young seedling growth, c) rooting, d) tillering, e) discolation, f) nutrition uptake, g) photosynthesis rate, h) delay in heading, i) pollen sterility, and j) grain fertility at low temperature are reported to be distinguishable. Relationships among those traits are not consistent. Reported studies on the inheritance of cold tolerance are summarized. Four or more genes are controlling low temperature germinability, one or several genes are controlling seedling tolerance, and four or more genes are responsible for the pollen fertility of the rice treated with cold air or grown in the cold water nursery. But most of those data indicate that the results may come out in different way if those were tested at different temperature. Many cold tolerant parents among Japonicas, Indicas and Javanicas were identified as the results of the improvement of cold tolerance screening techniques and IRTP efforts and they are ready to be utilized. Considering a) diversification of germ plasm, b) integration of resistances to diseases and insects, c) identification of adaptability of recommending cultivars and, d) systematic control of recommending cultivars, breeding strategies for short term and long term are suggested. For short term, efforts will be concentrated mainly to the conventional cultivar group. Domestic cultivars will be used as foundation stock and ecologically different foreign introductions such as from Hokkaido, China or from Taiwan, will be used as cross parents for the adjustment of growth durations and synthsize the prototype of tolerances. While at the other side, extreme early waxy Japonicas will be crossed with the Indica parents which are identified for their resistances to the diseases and insects. Through the back corsses to waxy Japonicas, those Indica resistances will be transfered to the Japonicas and these will be utilized to the crosses for the improvement of resistances of prototype. For the long term, efforts will be payed to synthsize all the available tolerances identified any from Japonicas, Indicas and Javanicas to diversify the germ plasm. The tolerant cultivars newly synthsized, should be stable and affected minimum. to the low temperature at all the growing stages. The resistances to the diseases and insects should be integrated also. The rapid generation advancement, pollen culture and international cooperations were emphasized to maximize the breeding efficiency.

  • PDF

Relationships of Changing Social Atmosphere, Lifestyle and Bone Mineral Density in College Students (대학생의 골밀도와 사회분위기 및 생활습관과의 관계)

  • Lee, In-Ja;Ko, Yo-Han;Kim, Chung-Kyung;Kim, Hee-Sol;Park, Da-Jeong;Yoon, Hyeo-Min;Jeong, Yu-Jin
    • Journal of radiological science and technology
    • /
    • v.36 no.4
    • /
    • pp.263-271
    • /
    • 2013
  • The decrease of bone mineral density gives rise to the outbreak of osteopenia and makes the possibility of a bone fracture. It makes health problems in society. It's very important to prevent osteopenia in advance. Also it's critical to prevent and take care of it in adolescent because it's the most developing period comparing to middle ages because that bone mineral density decreases. There are genetic, physical and enviromental factors that affect bone mineral density. Recently, a lifestyle and eating habits are also changing as the society atmosphere is gradually doing. This study have shown that 134 women and 75 men was chosen and responded to the survey of measuring bone mineral density and investigating a lifestyle. The measure of bone mineral density is to use Dual energy X-ray absorptiometry(DEXA) and check femoral neck and lumbar spine. Also questionaries was required to pre-made survey about their lifestyles. Analysis of data was done with SPSS program. Multiple regression analysis was used for the relation of bone mineral density, the heigths and BMI. The sample of Groups are checked for drinking, smoking or excercising about differences by t-test. The results of the experiments were; first, there is statistically significant differences in the comparisons between BMD and BMD. But there isn't any special correlation between drinking, smoking and BMD. Secondly, bone mineral density becomes low related to an intake of caffeine. Particularly, this is statically significant on women. Also there is statically significant correlation between femoral neck and quantity of motion for both men and women. Third, there is significant relation between eating habits and bone mineral density on women's lumbar spine. However, there is no significant relation between men's lumbar spine and women's one. Therefore, to prevent osteopenia, it's good to abstain from intaking caffeine within an hour after a meal. In addition, it's helpful to walk or run regularly and have a balanced meal.

Review: Distribution, Lactose Malabsorption, and Alleviation Strategies of Lactose Intolerance (유당불내증(Lactose Intolerance)의 발생 원인과 경감 방안에 대한 고찰)

  • Yoon, Sung-Sik
    • Journal of Dairy Science and Biotechnology
    • /
    • v.27 no.2
    • /
    • pp.55-62
    • /
    • 2009
  • Milk is called an almost complete food in terms of nutrition, especially for the younger generations because it contains a number of nutrients required for growth and development. Lactose intolerance is defined as a malabsorption of lactose in the intestine with some typical symptoms of abdominal pains and bloating, and occurred at 75% of global populations, which hampers milk consumption worldwide. Lacks of milk consumption in the underdeveloped countries frequently lead to many nutrients deficiencies, so that diseases including osteoporosis, hypertension, and colon cancer are more prevalent in the recent days. Lactose in foods needs to be hydrolyzed prior to intestinal absorption. The hydrolytic enzyme responsible for splitting lactose into its monomeric forms, glucose and galactose, is called as lactase or $\beta$-galactosidase. The former is primarily used as blood sugar and energy source and the latter used in glycolipid synthesis of brain tissues in infants. Lactose is clinically diagnosed with the breath hydrogen production test as well as intestinal biopsy. Reportedly, symptoms of lactose intolerance are widely prevalent at 25% of Europeans, 50 to 80% of Hispanics, South Indians, Africans, and Jews, almost 100% of Asians and native Americans. For the adults, phenotype of lactase persistence, which is able to hydrolyse lactose, is more common in the northern Europeans, but in the other area lactase non-persistence or adult-type hypolactasia is dominant. Genetic analysis on human lactase gene continued that lactase persistence was closely related to the err site of 1390 single nucleotide polymorphism from the 5'-end. To alleviate severity of lactose intolerance symptoms, some eating patterns including drinking milk a single cup or less, consumption along with other foods, whole milk rather than skimmed milk, and drink with live yogurt cultures, are highly recommended for the lactose maldigesters. Also, delay of gastric emptying is effective to avoid the symptoms from lactose intolerance. Frequency of lactose intolerance with conventional diagnosis is thought overestimated mainly because the subjects are exposed to too much lactose of 50 g rather than a single serving amount. Thus simple and accurate diagnostic method for lactose intolerance need to be established. It is thought that fermented milk products and low- or free lactose milks help improve currently stagnant milk consumption due to lactose intolerance which contributes to major barrier in milk marketing especially in Asian countries.

  • PDF

Modern approach of the discourse on viscera and bowels and retrogressive disorder (사상의학(四象醫學) 장부론(臟腑論)의 현대적 접근과 퇴행성질환의 조건)

  • Cho, Hwang-sung
    • Journal of Sasang Constitutional Medicine
    • /
    • v.12 no.1
    • /
    • pp.84-100
    • /
    • 2000
  • Are the body and th spirit to different things? How individual ability and feeling displays in a human being and what correation between the two lise physiologically? Namely, what determines the external and the internal world? By what physiological functions and circulations, it makes possible to indciate individual's characteristic? These kinds of questions in constitutional medicine is able us lead to the following approach.

  • PDF

Sex Reversal of Nile Tilapia (Oreochromis niloticus) by Immersion in a Solution of $17{\alpha}$-Methyltestosterone ($17\alpha$-Methyltestosterone의 침적처리에 의한 나일틸라피아(Oreochromis niloticus)의 성전환)

  • Noh, Choong-Hwang;Nam, Yoon-Kwon;Kim, Dong-Soo
    • Journal of Aquaculture
    • /
    • v.9 no.2
    • /
    • pp.141-149
    • /
    • 1996
  • Effects of $17{\alpha}$-methyltestosterone ($17{\alpha}-MT$) in rearing water on sex reversal of Nile tilapia (Oreochromis niloticus) were investigated and optimum conditions as initial treatment time, concentrations and treatment durations of hormone were evaluated in this study. For the study of the optimum initial treatment time, 0 to 20-day-old fry were treated by immersion in a 500 ppb solution of $17{\alpha}-MT$. Desirable results were obtained at 12-day-old fish as $86.4\%$ of male induction rates and this frequency was obviously higher than the other age groups. Twelve-day-old fry were immersed in $17{\alpha}-MT$ solutions at concentrations of $0\~2,000$ ppb for 24 hours for the study of dose dependent relationship between sex ratios and concentrations of $17{\alpha}-MT$, Male induction rates of all treated groups were higher than $80\%$, $X^2$ values against the sex ratio of control group indicate that sex reversal has taken place effectively in all experimental groups (P<0.001). Futhermore, 500 ppb treated groups showed highest male incidence of $86.4\%$. Effects of 5 different durations (0, 12, 18, 24 and 30 hours) treated with 1,000 ppb of $17{\alpha}-MT$ were also evaluated. Male induction rate from 0 to 24 hours treated group was increased with treatment durations. However, male incidence of 30-hour treated group ($84.0\%$) was sligthly decreased compare to the 24-hour treated group ($85.2\%$). It is concluded that immersion treatment using $17{\alpha}-MT$ on O. niloticus is possible on sex reversal at low concentration of 500 ppb and short treatment durations within 24 hours with 12-old-day fry.

  • PDF

Characteristics of Light-evoked Retinal Ganglion Cell Activity with Postnatal Maturation in SD Rat (SD rat 망막신경절세포의 생후 성숙기간에 따른 빛 자극 반응 특성)

  • Ye, Jang-Hee;Goo, Yong-Sook
    • Progress in Medical Physics
    • /
    • v.16 no.4
    • /
    • pp.214-219
    • /
    • 2005
  • As part of Korean retinal prosthesis project, we have provided preliminary experimental results regarding voltage parameters for the stimulation of chemically degenerated rabbit retina. Since our APB-treated chemically degenerated retina is only ON-pathway blocked, now we switch our experiments to more appropriate retinal degeneration model, genetically degenerated retina model (RD mouse: rd/rd (C3H/HeJ)). Before studying with RD mouse, we started control experiments with normal SD rat to understand characteristics of retinal ganglion ceil activity with postnatal maturation in rodents. Ganglion cell activities were recorded with 8${\times}$8 multi-electrode array. Moving spontaneous bursts appeared until postnatal day of 15. During pre-eye opening period, no light evoked response appeared. After postnatal day of 2 weeks (post-eye opening period), ON-, OFF- and ON/OFF response appeared. The fractional distributions of ON, OFF, and ON/OFF ganglion cell is about $40\%,\;50\%$, and $5\%$. The percentage ($\%$) of light evoked response in each dorso-temporal, ventral, and dorso-nasal area of eye is about $50\%,\;37.5\%$ and $12.5\%$, respectively. We concluded that the optimal period for experiment in rodent is about postnatal day of 2${\~}$3 weeks.

  • PDF