• 제목/요약/키워드: physiological factors

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기후변화와 인간의 방해 및 종간경쟁이 두루미 월동생태와 이동에 미치는 영향 (Effects of weather change, human disturbance and interspecific competition on life-history and migration of wintering Red-crowned cranes)

  • 홍미진;이후승;유정칠
    • 한국환경생태학회지
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    • 제29권5호
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    • pp.681-692
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    • 2015
  • 월동기간 동안 월동조류의 생리 및 영양학적 상태는 이후 번식지로의 이동성공과 번식성공에 영향을 줄 수 있음은 잘 알려져 있다. 그러나 환경적 요인들이 월동기간 동안 어떻게 몸 상태에 영향을 주어 장기적으로 이동과 번식에 영향을 주는지에 대해서는 아직까지 잘 알려져 있지 않다. 본 연구는 월동기간 동안 온도변화와 월동지에서의 인간 활동에 따른 방해가 개체수준에서의 월동하는 조류의 생활사에 미치는 영향과 번식지로의 이동 및 잠재적 번식 성공에 미치는 영향을 알아보기 위해 동적상태의존 월동 생활사 모델을 개발하였다. 모델에 사용된 지수는 월동개체군에 대한 연구가 잘 수행되어 있는 철원의 두루미 자료를 이용하였다. 모델은 온도 변화나 인간의 방해요인의 영향이 생존과 번식지로의 이동을 위한 에너지 축적 그리고 누적된 스트레스의 감소를 위한 자원 분배에 영향을 주는 것으로 예측하였다. 특히 월동지에 도래한 두루미 몸무게의 회복률은 기온변화가 적고 방해요인의 영향이 낮을수록 빨랐으며, 체내의 누적 스트레스는 기온변화가 크고 방해요인의 영향이 높을수록 회복속도가 낮을 것으로 예측되었다. 또한 월동지의 취식지를 공유하는 다른 종의 밀도가 높을수록 두루미의 몸무게 회복률이 낮은 것으로 예측되었다. 끝으로 모델의 예측된 결과를 통해 월동지에서의 월동조류 보전전략에 대해 고찰하였다.

Physiology, genomics and molecular approaches for lmproving abiotic stress tolerance in rice and impacts on poor farmers

  • Ismail, Abdelbagi M.;Kumar, Arivnd;Singh, R.K.;Dixit, Shalabh;Henry, Amelia;Singh, Uma S.
    • 한국작물학회:학술대회논문집
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    • 한국작물학회 2017년도 9th Asian Crop Science Association conference
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    • pp.7-7
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    • 2017
  • Unfavorable weather and soil conditions reduce rice yield and land and water productivity, aggravating existing encounters of poverty and food insecurity. These conditions are foreseen to worsen with climate change and with the unceasing irrational human practices that progressively debilitate productivity despite global appeals for more food. Our understanding of plant responses to abiotic stresses is advancing and is complex, involving numerous critical processes - each controlled by several genetic factors. Knowledge of the physiological and molecular mechanisms involved in signaling, response and adaptation, and in some cases the genes involved, is advancing. Moreover, the genetic diversity being unveiled within cultivated rice and its wild relatives is providing ample resources for trait and gene discovery, and this is being scouted for rice improvement using modern genomics and molecular tools. Development of stress tolerant varieties is now being fast-tracked through the use of DNA markers and advanced breeding strategies. Large numbers of drought, submergence and salt tolerant varieties were commercialized over recent years in South and Southeast Asia and more recently in Africa. These varieties are making significant changes in less favorable areas, transforming lives of smallholder farmers - progress considered incredulous in the past. The stress tolerant varieties are providing assurance to farmers to invest in better management of their crops and the ability to adjust their cropping systems for even higher productivity and more income, sparking changes analogous to that of the first green revolution, which previously benefited only favorable irrigated and rainfed areas. New breeding tools using markers for multiple stresses made it possible to develop more resilient, higher yielding varieties to replace the aging and obsolete varieties still dominating these areas. Varieties with multiple stress tolerances are now becoming available, providing even better security for farmers and lessening their production risks even in areas affected by complex and overlapping stresses. The progress made in these less favorable areas triggered numerous favorable changes at the national and regional levels in several countries in Asia, including adjusting breeding and dissemination strategies to accelerate outreach and enabling changes at higher policy levels, creating a positive environment for faster progress. Exploiting the potential of these less productive areas for food production is inevitable, to meet the escalating global needs for more food and sustained production systems, at times when national resources are shrinking while demand for food is mounting. However, the success in these areas requires concerted efforts to make use of existing genetic resources for crop improvement and establishing effective evaluation networks, seed production systems, and seed delivery systems to ensure faster outreach and transformation.

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그림 자료의 제시여부와 읽기모드에 따른 인지부하와 GSR의 차이 (Impact of Picture and Reading Mode on Cognitive Load and Galvanic Skin Response)

  • 류지헌
    • 감성과학
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    • 제13권1호
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    • pp.21-32
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    • 2010
  • 이 연구는 그림 자료의 근접성(고근접 vs. 저근접)에 따른 제시여부와 읽기모드(단순읽기 vs. 요약읽기)에 따른 학습자의 인지부하 차이를 검증하기 위한 것이다. 특히, 이 연구에서는 전기피부반응을 통하여 인지부하의 정도를 측정하였다. 실험참가자는 34명(통제집단=17명, 실험집단=17명)이었으며 고근접 조건과 저근접 조건에 대한 반복구획요인설계를 적용하였다. 또한 각 실험조건에서 측정된 과제난이도 지각점수를 공변량으로 투입하여 학습자의 사전지식에 의한 영향력을 통제하였다. 그림 자료의 근접성의 정도에 따라서 고근접 그림 자료와 저근접 그림 자료가 순차적으로 제시되었다. 처음에는 단순읽기 모드가 제시되었고 이후에 요약읽기를 수행하였다. 전기피부반응은 단순읽기와 요약읽기에서 모두 측정되었다. 이 연구의 종속변수는 전기피부반응과 지각된 난이도였다. 연구결과에 따르면 고근접 자료가 제시된 조건에서는 유의미한 차이를 발견할 수 없었다. 그러나 저근접 조건에서는 그림 자료의 제시여부 및 읽기모드 사이에서 유의미한 차이가 있었다. 즉, 저근접 조건에서는 텍스트만 제시하는 것보다는 그림 자료가 제시될 때 전기피부반응이 올라갔다. 또한 단순 읽기 보다 요약읽기에서 더 높은 전기피부반응이 측정되었다. 이 연구의 결과는 저근접 그림은 인지부하를 유발하는 요인이 될 수 있으며 읽기모드가 복잡해지면 인지부하가 높아질 수 있음을 보여주는 것이다. 동일한 자료를 활용한다고 하더라도 인지과정의 복잡성 정도에 따라서 인지부하가 달라질 수 있다는 것이다. 그러나 학습성취과 같은 과제수행 요인과 더 높은 난이도에서의 인지부하 측정에 대한 후속연구가 필요하다.

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혈액 내 코티졸의 패턴 변화가 발정 암캐의 P4 변화와 배란에 미치는 영향 (The Influence of Cortisol Level on Progesterone and Ovulation in the Estrus Dogs)

  • 박종주;김현민;최미경;노진구;염동현;지주영;김동교;김동훈;박진기;류재규
    • 한국수정란이식학회지
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    • 제28권3호
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    • pp.237-241
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    • 2013
  • It is generally accepted that chronic stress impairs female reproduction. It negatively affects ovarian function and the number of ovulated oocytes. Chronic stress lowers the number of retrieved oocytes. Ovarian follicular development is regulated by both pituitary-derived gonadotropins and intraovarian regulatory factors. The main corticosteroids are cortisol, cortisone, 11-deoxycortisol and corticosterone, cortisol being one of the most commonly used welfare and stress physiological indicator. In this study, we investigated the effect of cortisol level on progesterone patterns and ovulation in the dog. Cortisol and progesterone level of serum were analyzed by radioimmunoassay. The day of ovulation was considered as the day when serum progesterone concentration was 6.0~8.0 ng/ml. In vivo dog oocytes were collected by flushing oviducts of mixed-breed bitches at three days after ovulation. We classified dogs as having group 1 (cortisol level, 0 ${\leq}$ or < $2{\mu}g/dl$), group 2 (corisol level, 2 ${\leq}$ or < $4{\mu}g/dl$), group 3 (cortisol level, 4 ${\leq}$ or < $6{\mu}g/dl$) and group 4 (cortisol level, $6{\mu}g/dl$ ${\leq}$). The patterns of progesterone were not different in four cortisol groups. The average numbers of retrieved oocytes was not different in four cortisol groups. These results suggest that different cortisol levels on estrus dogs do not affect ovulation, number of ovulated oocytes and progesterone changes.

우리나라 소화기암 환자들의 대체의료이용에 관한 연구 (Use of Complementary and Alternative Medicine among Cancer Patients in Korea)

  • 정은영;한동운;최병희;김유겸;박연희
    • 동의생리병리학회지
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    • 제21권6호
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    • pp.1590-1596
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    • 2007
  • Complementary and alternative medicine (CAM) has gained in popularity among cancer patients in recent years. The use of CAM in cancer patients is common with about one third of patients using some form of CAM in Western countries. The purpose of this study was to analyze the use of CAM and determine what factors affect to use CAM among cancer patients to provide CAM therapy information and assist therapy selection among various CAM therapies to cancer patients. The design of the study was descriptive cross-sectional, and data were collected using a 16-item questionnaire. This study was conducted in subjects with confirmed diagnosis of stomach, colon, liver, or pancreas cancer, in both out-patients clinics and inpatients setting in a tertiary hospital in Seoul Korea. As a result, among the participants, past or current CAM use was reported by 75%, which shows a statistically significant difference in income groups(P<0.05), but no difference in age and religion groups. The most common therapies use by cancer patients included traditional Korean medicine (32.1%), folk remedies (26.6%), exercise (14%), dietary supplements (11.6%), physical therapy (9.9%), diet therapy (5%), and meditation (4%). 77.8% of patients show satisfaction and 64.4% shows perceived effectiveness of CAM. Male patients with higher income, and previous treatment were more likely to use CAM. The main benefits from CAM reported by cancer patients were psychological improvement and symptom improvement. Of the cancer patients used CAM, 30.9% were dissatisfied, 25.8% did not have benefits from the use, and 7.6% experience side effects. Cancer patients who prefer CAM (more than 3 kinds) used it to cure cancer, on the contrary, the one who do not prefer CAM used to improve symptoms and psychological stability. The main sources of information about CAM were family and friends(54.4%), and media(24.5%), doctor and nurse(18.3%), and religion group(2.6%). Findings suggest that due to the relatively high use of CAM among cancer patients in Korea, this topic should be taken into account in the development of a holistic approach to cancer patients and efficient cancer patients management system and proactive and consistent management of CAM is necessary in the health care system in Korea.

식물색소 관여형 화합물의 생물검정법으로서 Greening Assay (A Bioassay for Chemicals Affecting Plant Pigment Biosynthesis: Greening Assay)

  • 김진석;김태준;홍경식;황인택;조광연
    • 한국잡초학회지
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    • 제10권3호
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    • pp.214-220
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    • 1990
  • 식물색소 생합성에 마치는 화합물의 스크리닝 및 생리 생화학적 실험을 위한 Greening assay를 확립하고자 greening 에 미치는 환경요인과 치상 및 조사 방법에 관한 여러가지 실험을 수행한 결과를 요약하면 다음과 같다. 오이 및 보리 모두 $25^{\circ}C$ 암조건에 5~6 일 된 것이 greening 에 양호한 반응을 보였다 2. 오이는 자엽의 표면이 용액에 닿도록 치상하는 것이, 보리엽신은 상단으로부터 0.5~2.0cm 부위을 절취하는 것이 greening 에 양호하였다. 3. Buffer 는 10mM potassium phosphate(pH 6.0)를 사용하는 것이 바람직할 것으로 여겨진다. 4. 광조사시 온도가 $15\sim35^{\circ}C$ 범위일 경우 온도가 높을수록 greening 속도가 빨랐으며, 그 반응은 보리보다 오이가, carotenid 보다는 엽록소 생합성이 더욱 민감하였다. 5. 광도에 대한 영향은 엽록소의 경우 오이는 5,000 Lux. 보리는 1,000 Lux 내외에서 최고치를 보였으며, carotenoid의 경우는 이보다 높은 광도에서 최고치를 보이는 경향이었다. 6. 용매의 안전사용농도는 acetone 10% 미만, ethyl alcohol 0.1 % 이하, DMSO 2.5 %이 하였고, 색소 생합성에 관여되는 제초제 또는 몇가지 시약의 $pI_{50}$을 구하였다.

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Consequences of Post-grazing Residues Control and Birth Season on the Body Traits, Reproductive Performance and Offspring's Growth of Suckling Goats and Ewes Reared at Pasture in Guadeloupe (FWI)

  • Ortega-Jimenez, E.;Alexandre, G.;Arquet, R.;Coppry, O.;Mahieu, M.;Xande, A.
    • Asian-Australasian Journal of Animal Sciences
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    • 제16권8호
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    • pp.1108-1117
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    • 2003
  • In Guadeloupe small ruminants (SR) are reared for meat production under pasture conditions. Intensive rotational grazing systems (irrigated, fertilised and high stocked) allow reasonable levels of production but generate high post-grazing residues. Experiments were designed to control them. A system in which residuals were mown (RM) was tested in comparison to the control system (Residuals Remained, RR). The same design was carried out for two years with Creole goat (G) and Martinik sheep (S). An accelerated reproductive rate (3 parturitions over 2 years) was carried out. Systems were compared at three parturition seasons per year(dry, intermediate and rainy seasons). Each group was composed of 20 goats ($36.0{\pm}2.5kg$) or 20 ewes ($46.8{\pm}2.4kg$). The female body traits did not vary according to pasture management and seasons. The stocking rate averaged 1,400 kg LW/ha. The mean fertility rate for does varied significantly (p<0.05) within the kidding season, from $80.4{\pm}0.5%$ to $93.7{\pm}2.9%$ while the mean litter size was $2.30{\pm}0.07$ total kids born. No effect of pasture system was observed. Corresponding values for ewes were $83.2{\pm}12.8%$ vs. $75.6{\pm}12.5%$ (p<0.05) and $2.43{\pm}0.24$ vs. $2.03{\pm}0.29$ (p<0.01) total lambs born for SRM and SRR ewes, respectively. A seasonal effect was observed upon ewe performances. The preweaning mortality of kids and lambs averaged 16.3% and 14.4%, respectively. It was 7 and 9 percentage points more (p<0.01) for RR than for RM kids and lambs, respectively. For both species, weaning took place at an average age of $81.4{\pm}3.6days$. In Creole kids, live weight at birth and at weaning were $1.9{\pm}0.2kg$ and $8.9{\pm}0.8kg$, respectively. In the Martinik sheep, the traits averaged $2.9{\pm}0.2kg$ and $18.9{\pm}0.9kg$. For both traits in both species, significant (p<0.05) group${\times}$season interactions were recorded. The consequences of elimination of post-grazing residues varied according to the SR species, the environmental conditions and the animal physiological status. The forage characteristics were not limiting factors since forage availability in the RM systems (2,300 and 2,600 kg DM/ha, respectively) and chemical composition were at satisfactory levels (CP content averaged 12 and 10%). It is recommended to develop new grazing system which would allow the use of post-grazing residues instead of mowing the refusals.

한냉에 노출된 인체의 냉각과 총지방량 및 S/V 비율 사이의 관계 (Relationship between Total Body Fat and S/V Ratio and Body Cooling for Two Hours at $15^{\circ}C$)

  • 정관옥;남기용
    • The Korean Journal of Physiology
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    • 제3권1호
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    • pp.19-28
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    • 1969
  • Skin temperatures on 10 sites and rectal temperature at every 10 minutes, oxygen consumption at every 20 minutes were measured on 18 male subjects (ages between 14 and 47 years) after exposure to cold air at $15^{\circ}C$ for two hours in a climatic room. Total body fat measured by means of a skinfold method and ratio of body surface area (S) to body volume (V), S/V, were utilized as basis of observations. Surface area was calculated after DuBois equation and body volume was calculated by our original formula. In influencing on the heat loss from the body core to the cold environment, % fat showed inverse relations, whereas, S/V ratio showed direct relations. Thus these two factors acted antagonistically on the body heat loss. Local skin temperatures showed negative correlations with skinfold thickness on the same site, nemaly, on chest, r=-.567; on back, r=-.507; and on upper arm, r=-.353. The other 7 skin sites showed low correlations with % fat. Minimum mean weighted skin temperature (MWST) showed a negative correlation (r=-.443) with % fat, and showed no correlation with S/V ratio. Oxygen consumption in the cold air at $15^{\circ}C$ increased from the first measurement at 20 minutes after exposure and maintained the same increasing trend up to 120 minutes. ${\Delta}T_R$ was greater in tile lean subjects who showed a greater % change in oxygen consumption. The antagonistic actions of % fat and S/V ratio on the heat loss were manifested by observations as follows: minimum rectal temperature was higher In fat subjects (r=.600) and lower in subjects with a greater S/V ratio (=-.582), ${\Delta}T_R$ was smaller in fat subjects (r=-.738) and greater in subjects with a greater S/V ratio (r=.618). Temperature difference between body core and skin surface (minimum rectal temperature minus minimum MWST) showed a positive correlation with % fat (r=.600) and a negative correlation with S/V ratio (r=-.881). Decrease in the mean body temperature and heat debt, respectively, showed negative correlations with % fat and positive correlations with S/V ratio.

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둥근성게(Strongylocentrotus nudus) Estrogen Receptor-Related Receptor(ERR)의 초기 발생시 유전자 발현 패턴과 전사 활성 (Gene Expression Pattern during Early Embryogenesis and Transcriptional Activities of Estrogen Receptor-Related Receptor(ERR) in Sea Urchin, Strongylocentrotus nudus)

  • 맹세정;김미순;손영창
    • 한국발생생물학회지:발생과생식
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    • 제13권4호
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    • pp.249-256
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    • 2009
  • 구조적으로 estrogen 수용체(estrogen receptor, ER)와 유사한 estrogen receptor-related receptor(ERR)는 포유동물에서 배발생 후기에 외배엽 형성과 관련되어 있다고 알려진 고아핵수용체(orphan nuclear receptor)이다. ERR은 ER과 DNA binding domain의 보존성은 유사하지만, ligand 결합 및 전사 활성은 다르다. 포유동물의 ERR에 관한 연구에 비하여 해양 무척추동물의 ERR에 대한 기능 연구는 매우 부족하다. 본 연구에서는 우리나라 동해안에 주로 서식하는 둥근성게(Strongylocentrotus nudus) ERR의 초기 발생기 유전자 발현 변화와 전사 활성 기능을 조사하기 위해 먼저 polymerase chain reaction(PCR)을 이용하여 cDNA를 동정하였다. 둥근성게 ERR은 S. purpuratus와 91%의 높은 상동성을 보였으며, 계통수 분석을 통해 무척추동물 ERR의 clade에 포함되는 것을 알았다. 둥근성게 배발생 시기에 ERR 유전자 발현을 알아보기 위하여 real-time PCR을 실시한 결과, 4~64세포기와 유생기에 mRNA level이 높은 경향을 나타내었다. 또한 호르몬 및 co-regulator에 의한 둥근성게 ERR의 전사 활성을 조사한 결과, 호르몬에 의한 특이성은 확인되지 않았지만, peroxisome proliferator activated receptor-(PPAR) $\gamma$ coactivator $1\alpha$(PGC-$1\alpha$)가 둥근성게 ERR의 coactivator임을 입증할 수 있었다. 이 연구 결과는 향후 새로운 ligand 발굴과 coregulator와 의 상호작용 연구에 도움이 될 것으로 사료된다.

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Di-(2-ethylhexyl)phthalate에 의한 흰쥐 간세포 미세구조와 metallothionein 발현에 미치는 영향 (Ultrastructure and Metallothionein Expression in Rat Liver Treated with Di-(2-ethylhexyl)phthalate)

  • 김다함;문승훈;이미영;이종화;박영현;신길상;김완종
    • 환경생물
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    • 제25권4호
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    • pp.289-296
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    • 2007
  • 본 연구에서는 내분비계 장애물질으로 알려져 있고, 플라스틱 제품의 가소제로 사용되고 있는 di-(2-ethylhexyl) phthalate (DEHP)가 흰쥐의 간세포 미세구조와 간조직내 metallothionein (MT)의 발현 양상에 미치는 영향을 조사하였다. DEHP는 흰쥐 간세포의 미세구조와 MT 발현에 영향을 주었다. 실험군의 경우 조면소포체가 발달하고, 미토콘드리아가 증가하며 리소솜 혹은 퍼옥시좀들이 증가하는 경향을 나타냈다. 한편, MT 발현의 변화를 면역세포 화학적 방법과 western Blot을 수행한 결과 저농도 투여군에서는 약 1.5배, 고농도 투여군에서는 약 2배 가량 증가하는 결과를 나타냈다. 결론적으로 DEHP는 흰쥐 간세포의 구조와 기능에 영향을 주는 것으로 판단되며, 이러한 세포내 스트레스가 MT 발현 증가 현상과 연관이 있을 것으로 판단된다.