• Title/Summary/Keyword: C35

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Temperature-dependent Development of Aphis gossypii Glover and Aphis egomae Shinji on Leaves of Green Perilla and Their Seasonal Abundance Patterns in Protected Greenhouse in Guemsan, Korea (들깨 잎에서 목화진딧물(Aphis gossypii Glover)과 들깨진딧물(Aphis egomae Shinji)의 온도발육 및 금산지역 잎들깨 시설하우스에서 발생소장)

  • Choe, Yong-Seok;Park, Deok-Gi;Han, Kwang-Seop;Choe, Kwang-Ryul
    • Korean journal of applied entomology
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    • v.45 no.3 s.144
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    • pp.269-274
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    • 2006
  • Temperature-dependent development studies of two aphid species, A. egomae and A. gossypii occurring in green perilla greenhouse were conducted at $15{\sim}35^{\circ}C$, and 16:8 (L:D h) of light period in the laboratory. The mortality of two aphid species was high in young stages (1st and 2nd). In A. egomae, the mortalitiy increased with increasing and decreasing temperature: the mortalitie at $15^{\circ}C$ and $35^{\circ}C$ were 22.3% and 15.6%, respectively. While the mortalities of A. gossypii increased with increasing temperature: the mortality at $35^{\circ}C$ was 50.0%. The developmental periods of A. egomae and A. gossypii ranged from 20.8days to 5.4days and from 22.6days to 9.1days at $15^{\circ}C$ to $30^{\circ}C$ of temperature resion, respectively, and were 7.2days and 10.7days at $35^{\circ}C$ for each species. The lower developmental threshold temperatures for total nymphs of A. egoame and A. gossypii were $9.9^{\circ}C$ and $4.9^{\circ}C$, respectively and an effective degree-days (DD) for the developmental completion of total nymph were 108.0 DD for.A. egomae and 221.2DD for A. gossypii. In green perilla greenhouse, the occurrence period of A. gossypii was earlier about 15 days than that of A. egomae. When the occurrence period of two aphid species was estimated by degree-days based on lower threshold temperatures, A. gossypii occurred earlier than A. egomae in the field. A. gossypii occurred from early April and showed dominant position to late May compared with A. egomae Whereas, A egomae started to occur from mid April and then were abundant after late May followed by abrupt population crash around late July.

Studies on the Screening for Cold Tolerance in Soybean (대두내냉성계통선발에 관한 연구)

  • Kwon, S.H.;Lee, Y.I.
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.23 no.1
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    • pp.32-35
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    • 1978
  • In order to screen cold tolerant soybean lines, germination at various temperature, and emergence and seedling height at 1$0^{\circ}C$ were investigated. Since the most conspicuous varietal difference of the germination speed was observed at 1$0^{\circ}C$, the germination test at 1$0^{\circ}C$ would be effective in screening cold tolerant lines.

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Changes of Biogenic Amine Level during Storage and Development of New Quality Index on Silkworm Pupa (식용 번데기의 저장 중 Biogenic Amine 함량 변화와 품질지표 개발)

  • Cho, Tae-Yong;Han, Gyu-Hong;Kang, Byung-Sun;Kim, Seon-Bong
    • Journal of Food Hygiene and Safety
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    • v.22 no.4
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    • pp.268-272
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    • 2007
  • A study on the evolution of acid value, peroxide value and biogenic amines in silkworm pupa during 7 days at different temperature of storage (-18, 25 and $35^{\circ}C$) was performed. Seven biogenic amines (putrescine, cadaverine, histamine, tyramine, spermidine, spermine and 2-phenylethylamine) were determined. Acid value in Silkworm pupa increased both during normal temperature $(25^{\circ}C)$ and room temperature $(35^{\circ}C)$ and thebiogenic amine (histamine, tyramine) content generally increased in $25^{\circ}C\;and\;35^{\circ}C$ with storage time. Significant differences were found (P<0.05) in the levels of tyramine and histamine among Silkworm pupa. The relationship of storage time and acid value of Silkworm pupa were resolved a simple linear equation, and histamine and tyramine could be predicted using this equation. Quality indices related to the contents of the major biogenic amines were calculated and they correlated well with physicochemical characteristics qualities such as acid value.

Inhibition of Listeria monocytogenes by Low Concentrations of Ethanol (저농도의 Ethanol에 의한 Listeria monocytogenes의 증식억제)

  • 박찬성;김미림
    • Korean journal of food and cookery science
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    • v.11 no.4
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    • pp.379-385
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    • 1995
  • The effect of low concentrations of ethanol (3-7%, v/v) in tryptic soy broth (TSB) as an antibacterial agent against Listeria monocytogenes was tested at -20, 5, 35, 45, 50 and 55$^{\circ}C$. Increasing concentrations of ethanol progressively inhibited initial growth of L. monocytogenes at 35$^{\circ}C$. Growth occured at 5% ethanol, but only after a prolonged lag period. The number of viable cells of L. monocytogenes declined during incubation at 7% ethanol. TSB containing 3-7% ethanol was inoculated with 10$\^$5/-10$\^$6/ cells/$m\ell$ or L. monocytogenes and incubated at low temperatures (5$^{\circ}C$, -20$^{\circ}C$). In the presence of 3% of ethanol at 5 or -20$^{\circ}C$, bacterial growth was inhibited more than 90% of control cells. TSB containing 3-7% ethanol was inoculated with 10$\^$6/-10$\^$7/ cells/$m\ell$ of L. monocytogenes and incubated at high temperatures (45$^{\circ}C$, 50$^{\circ}C$, 55$^{\circ}C$). Decrease in viability of the cells incubated at 45 or 50$^{\circ}C$ was slow and the survival of L. monocytogenes was not affected so much in the presence of 3% of ethanol. The viability of L. monocytogenes was decreased with increasing concentration of ethanol and temperature. Decimal reduction times (D-values) based on tryptic soy agar plates at 55$^{\circ}C$ were 20.1, 12.6, 7.4 and 4.2 min in 0, 3, 5 and 7% ethanol, respectively.

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The Brain Temperature Change after the Use of Mobile Phone (휴대전화 사용 후 뇌 온도의 변화)

  • Koo, Eun-Jung;Lee, Il-Keun;Kong, Hea-Won
    • Annals of Clinical Neurophysiology
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    • v.5 no.1
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    • pp.16-20
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    • 2003
  • Background: Mobile phone has become a very popular device used in everyday our lives. However, the possible hazard to human body such as brain tumor has been proposed intermittently. This unwanted possibility was calmed down due to the absence of definite evidence of hazard. This study was performed to see the effect of mobile phone use on the brain temperature. Methods: In 20 volunteers, we performed 4 steps of temperature measuring procedure. Four steps are pre-use (S1, basal state), wire-phone (S2, conventional telephone), PCS phone (S3, using 1,750~1,900 MHz), cellular phone (S4, using 820 MHz) states. Brain temperatures were measured by radiothermometer at 10 sites (5 sites in each hemisphere) of the brain after 5minutes of telecommunication through the phones. The final data were compared using paired t-test. Results: In PCS phone user group (Average; $35.73708^{\circ}C$), brain temperature decreased (with statistical significance, p<0.05), compared to those of non-user group (Average; $35.9527^{\circ}C$) or conventional wire phone user group. In cellular phone user group (Average; $35.82155^{\circ}C$), brain temperature decreased slightly (without statistical significance, p>0.05) compared to those of non-user group (Average; $35.9527^{\circ}C$) or conventional wire phone user group (Average; $35.922^{\circ}C$). The temperature change was not limited to the mobile phone applied side but on both hemisphere of the brain. Conclusion: In conclusion, mobile phone (especially PCS phone) decreased brain temperature in both hemispheres without side-to-side temperature difference. In addition, this study suggests possibility of radiothermometer application to the study of electromagnetic wave effect and protection method research in the future.

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Development of the Turnip Aphid, Lipaphis erysimi Kaltenbach (Homoptera: Aphididae), and Test of Insecticidal Efficacy of Some Commercial Natural Products

  • Kim, Dong-Young;Chang, Sung-Kwon;Jeong, Hyung-Uk;Kim, Min-Jee;Kim, Ik-Soo
    • International Journal of Industrial Entomology and Biomaterials
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    • v.16 no.2
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    • pp.93-99
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    • 2008
  • The turnip aphid is a worldwide pest, damaging mainly to crucifers. In order to understand the life parameters of Lipaphis erysimi for the eventual goal of control, the developmental periods, survival rates, lifespan, and fecundity of the species were investigated under five temperature regimes ($15^{\circ}C-35^{\circ}C$). Furthermore, the efficacy of several environment-friendly agricultural materials (EFAMs) that are on the market was subjected to test in order to obtain further accurate information. The developmental period of the turnip aphid nymph was longest at $15^{\circ}C$ as 16.9 days, shortened as temperature goes up to $25^{\circ}C$ (5.4 days), and then somewhat increased at $30^{\circ}C$ (5.9 days), suggesting that the most efficient temperature for nymphal development could be around $25^{\circ}C$. Mortality of the nymphal turnip aphid was obvious at $35^{\circ}C$, whereas it was minimal at other temperature schemes. The longevity of adults shortened as temperature goes up to $30^{\circ}C$. In particular, the maximum lifespan for adults continued for 55 days at $15^{\circ}C$, but shortened to 21 days at $30^{\circ}C$. The total fecundity was 35.7 at $15^{\circ}C$, 81 at $20^{\circ}C$, 64.2 at $25^{\circ}C$, and 6.6 individuals at $30^{\circ}C$, showing the highest fecundity at $20^{\circ}C$. After the turnip aphids were successfully stabilized in indoor environment the insecticidal activity was tested and mortality was determined 12, 24, 36, and 48 hrs after EFAMs are treated. Several on-the-market EFAMs showed more than 90% of insecticidal activity within 24 hrs or 48 hrs, but a few showed less than 90% activity, signifying importance of selection of proper EFAMs.

Effect of cooling water temperature on the temperature changes in pulp chamber and at handpiece head during high-speed tooth preparation

  • Farah, Ra'fat I.
    • Restorative Dentistry and Endodontics
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    • v.44 no.1
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    • pp.3.1-3.10
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    • 2019
  • Objectives: It was the aim of this study to evaluate the effect of cooling water temperature on the temperature changes in the pulp chamber and at the handpiece head during high-speed tooth preparation using an electric handpiece. Materials and Methods: Twenty-eight intact human molars received a standardized occlusal preparation for 60 seconds using a diamond bur in an electric handpiece, and one of four treatments were applied that varied in the temperature of cooling water applied (control, with no cooling water, $10^{\circ}C$, $23^{\circ}C$, and $35^{\circ}C$). The temperature changes in the pulp chamber and at the handpiece head were recorded using K-type thermocouples connected to a digital thermometer. Results: The average temperature changes within the pulp chamber and at the handpiece head during preparation increased substantially when no cooling water was applied ($6.8^{\circ}C$ and $11.0^{\circ}C$, respectively), but decreased significantly when cooling water was added. The most substantial drop in temperature occurred with $10^{\circ}C$ water ($-16.3^{\circ}C$ and $-10.2^{\circ}C$), but reductions were also seen at $23^{\circ}C$ ($-8.6^{\circ}C$ and $-4.9^{\circ}C$). With $35^{\circ}C$ cooling water, temperatures increased slightly, but still remained lower than the no cooling water group ($1.6^{\circ}C$ and $6.7^{\circ}C$). Conclusions: The temperature changes in the pulp chamber and at the handpiece head were above harmful thresholds when tooth preparation was performed without cooling water. However, cooling water of all temperatures prevented harmful critical temperature changes even though water at $35^{\circ}C$ raised temperatures slightly above baseline.