• ALGAE
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• v.27 no.3
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• pp.215-224
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• 2012

Growth dynamics of the seagrass, Zostera marina were examined at the two stations (Myungju and Dagu) in Jindong Bay on the southern coast of Korea. Eelgrass leaf productivities, underwater irradiance, water temperature, dissolved inorganic nitrogen (DIN) in water column and sediments, and tissue carbon (C) and nitrogen (N) content were monitored monthly from March 2002 to January 2004. Underwater irradiance fluctuated highly without a clear seasonal trend, whereas water temperature showed a distinct seasonal trend at both study stations. Water column DIN concentrations were usually less than $5{\mu}M$ at both study sites. Sediment pore water $NH_4{^+}$ and $NO_3{^-}+NO_2{^-}$ concentrations were higher at the Myungju site than at the Dagu site. Eelgrass leaf productivity at both study sites exhibited a distinct seasonality, increasing during spring and decreasing during summer. Seasonal variation of eelgrass productivity was not consistent with seasonal patterns of underwater irradiance, or water temperature. Eelgrass tissue C and N content at both study sites also showed significant seasonal variations. Relationships between tissue C and N content and leaf productivities exhibited usually negative correlations at both study sites. These negative correlations implied that the growth of Z. marina at the study sites was probably limited by C and N supplies during the high growth periods.

• Transactions of the Korean Society of Mechanical Engineers
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• v.8 no.5
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• pp.442-449
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• 1984

Turbulent jet flow has been studied in many ways; a plane jet, a rectangular jet, an annular jet, a round jet, a wall jet, a parallel jet, a valve jet, a cross jet, a slit jet and etc. In this report, a 45.deg. cross jet flow was tried by using two same dimensioned nozzels(dia..phi.20)which were set up at the exit of the subsonic wind tunnel. Each jet flows to the direction of 22.5.deg. to the axis of downstream of the mixed flow. The centerline of each jet meets at the distance of 217.3mm and their mixing flow could be imagined to develop beyond that distance, so the measurement was effectuated at X/X$_{0}$=1.2-1.5. The section of the mixed flow a elliptic circle which is formed by the 22.5.deg. inclined flows to the X direction. This experimental study aimed at the investigation of the turbulent mixing process of two jets; the mean velocities, the turbulent shear stresses, the correlation coefficients, and the momentum were respectively measured. The mean velocity distribution profiles of the down-stream component measured in the Y direction coincide well with the empirical equation of Gortler and those measured in the Z direction agree with the equation of H. Schlichting. Other mean velocities V over bar and W over bar components were randomly distributed. The higher values with same order of the intensity of turbulence were largely distributed at the central part of the flow. The momentum was decreased up to 70% by the shock losses and the development of intense turbulences, but it kept its value constantly beyond X/d=14. Two-channel hot-wire anemometer systems (model 1050 series), X-type hot-wire made of tungsten (dia. .phi.e.mu.m, long 3mm, model 0252 T5), a computer(model HP 9845B0, and a plotter (model HP 9872C) were used for the experiments and the analyses.s.

• Atmosphere
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• v.26 no.3
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• pp.445-459
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• 2016

Air temperature deviation (ATD) is one of major indicators to represent spatial distribution of urban heat island (UHI), which is induced from the urbanization. The purpose of this study is to evaluate the accuracy of air temperature deviation about Climate Analysis Seoul (CAS) workbench, which had developed by National Institute Meteorological Science and TU Berlin. Comparison and correlation analysis for CAS ATD including meso-scale air temperature deviation, local-scale air temperature deviation, total air temperature deviation, surface heat flux deviation, cold air production deviation among meso-scale numerical modelling variable in 'Seoul Region', micro-scale numerical modelling in 'Detail Region', and CAS workbench variable using observation data in ground stations. Comparison between night time OBS ATD and CAS ATD show that have most close values. Most of observations ($dT_{max}$ and $dT_{min}$) have highly positive ($dT_{SHP}$, $dT_{CA}$, MD, TD, $f_{BS}$, $f_{US}$, $f_{WS}$, $h_B$) and negative ($f_{VS}$, $f_{TV}$, $h_V$, Z) correlations. However, CAS workbench needs further improvement of both observational framework and analytical framework to resolve the problems; (1) night time OBS ATD of has closer values in compare with at high rise mountain area and (2) correlations are very dependable to meteorological scale.

• Molecules and Cells
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• v.40 no.6
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• pp.426-433
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• 2017

Ephrin-A5 has been implicated in the regulation of brain morphogenesis and axon pathfinding. In this study, we used bacterial homologous recombination to express a LacZ reporter in various ephrin-A5 BAC clones to identify elements that regulate ephrin-A5 gene expression during mesencephalon development. We found that there is mesencephalon-specific enhancer activity localized to a specific +25.0 kb to +30.5 kb genomic region in the first intron of ephrin-A5. Further comparative genomic analysis indicated that two evolutionary conserved regions, ECR1 and ECR2, were present within this 5.5 kb region. Deletion of ECR1 from the enhancer resulted in disrupted mesencephalon-specific enhancer activity in transgenic embryos. We also found a consensus binding site for basic helix-loop-helix (bHLH) transcription factors (TFs) in a highly conserved region at the 3'-end of ECR1. We further demonstrated that specific deletion of the bHLH TF binding site abrogated the mesencephalon-specific enhancer activity in transgenic embryos. Finally, both electrophoretic mobility shift assay and luciferase-based transactivation assay revealed that the transcription factor Ascl1 bound the bHLH consensus binding site in the mesencephalon-specific ephrin-A5 enhancer in vitro. Together, these results suggest that the bHLH TF binding site in ECR1 is involved in the positive regulation of ephrin-A5 gene expression during the development of the mesencephalon.

• Journal of Power System Engineering
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• v.5 no.2
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• pp.22-29
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• 2001

This paper represents axial mean velocity, turbulent kinetic energy and swirl number based on momentum flux measured in the X-Y plane and Y-Z plane respectively of a cone type gas swirl burner by using X-probe from the hot-wire anemometer system. This experiment is carried out at flow rates 350 and $450{\ell}/min$ respectively, which are equivalent to the combustion air flow rate necessary for heat release 15,000 kcal/hr in gas furnace, in the test section of a subsonic wind tunnel. Axial mean velocities and turbulent kinetic energies show that their maximum values exist centering around narrow slits situated radially on the edge of and in the forefront of a burner until $X/R{\fallingdotseq}1.5$, but they have a peculiar shape like a starfish diffusing and developing into inward and outward of a burner by means of the mixing between flows ejected from narrow slits, an inclination baffle plate and swirl vanes respectively according to downstream regions. Moreover, they show a relatively large value in the inner region of 0.5$S_m$ obtained by integration of velocity profiles shows a characteristic that has an inflection point composing of the maximum and minimum value until X/R<3, but shows close agreement with the geometric swirl number after a distance of X/R=3.

• Journal of Marine Bioscience and Biotechnology
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• v.9 no.1
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• pp.8-13
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• 2017

Cost-effective microalgae harvesting methods are necessary for economical production of algal biodiesel. In this study, membranes with various pore sizes and materials were examined for their potentials in application to gravity-filtration of Tetraselmis sp. KCTC12432BP. For this test, 10 L of Tetraselmis sp. culture (2 g/L) was loaded on each membrane and filtration rates were measured. Among the tested materials, a woven cotton fabric showed the fastest water drain rate (0.73 L/hr) without serious cell leakage. Cell density of the concentrates after filtration was 6.8 g/L, indicating 3.4-fold concentration compared with the initial algal culture. The result suggests that the woven cotton fabric could serve as filtration membrane for harvesting Tetraselmis sp. among the tested ones.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.2
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• pp.244-249
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• 2004

The effects of supplemental betaine ($Betafin^{(R)}$) in the drinking water (50 g/kg) (WB) or feed (100 g/kg) (FB) were investigated on male broiler chickens ($Cobb{\times}Cobb$) exposed to 4 h episodes of heat stress at $34{\pm}1^{\circ}C$ on day (d) 35 and $36{\pm}1^{\circ}C$ from d 36 to 41. Prior to (d 1 to 34) and following heat exposure (d 35 to 41), betaine supplementation had no significant effect on body weight, total feed intake and cumulative feed conversion ratios of broilers. The total water intake of WB chicks was lower compared to controls. Prior to heat exposure, there was no difference in percentage of mortality among the three dietary groups. Following the heat challenge period, although higher percentage of control chicks succumbed to the heat challenge as compared to those of WB, it was not significantly different. The WB and FB chicks were less hyperthermic than controls in response to the heat challenge. Irrespective of treatment groups, the heat treatment resulted in a marked elevation in heterophil/lymphocyte ratios (HLR). The WB birds, however, had smaller increase in HLR than those of controls during heat exposure. Antibody production against Newcastle disease vaccine on day 35 was not affected by betaine supplementation. On d 42, WB birds had higher antibody production than those of FB. It is concluded that the WB treatment, as measured by HLR, antibody production and mortality rate, has advantages over the FB group under heat stress conditions.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.4
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• pp.470-473
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• 2000

The experiment was carried out to evaluate the effect of varying levels of flaked com abomasally infused on energy metabolism and nitrogen metabolism in fattening steers. The starch levels of flaked corn of abomasally infused were 0, 300, 600 and 900 g/d. Four mature fattening steers fitted with permanent abomasum cannulas were allocated to a $4{\times}4$ Latin square design were fed at 1.2 maintenance requirement a basal diet of Chinese wildrye (Aneurolepidium Chinense). Compared with 0 g/d (control group), digestible nitrogen, retention nitrogen (RN, g/d) and the efficiency of digestible nitrogen converted into retention nitrogen (RN/DN, %) of 300, 600 and 900 g/d groups were higher (p<0.05). The post-ruminal starch digestion of flaked corn were 71.36, 80.27 and 64.71 % when the amounts abomasally infused were 300, 600 and 900 g/d, respectively. When the amount of starch abomasally infused was more than 600 g/d, the post-ruminal digestion of starch decreased. 300, 600 and 900 g/d starch infusion groups showed higher metabolizable energy intake (ME) and net energy gains (NEg, MJ/d) than the control group, and the efficiencies of metabolizable energy converted into body weight (Kf, %) of these groups were higher than the control group by 38.31, 73.18 and 67.06% (p<0.05). Kf (Y, %) had a positive curved relation to starch of flaked com abomasally infused (X, g/d), $Y=36.1605X^{0.0760}$ (n=16, r=0.9308).

• Korean Journal of Adult Nursing
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• v.17 no.4
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• pp.646-655
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• 2005

Purpose: This study was conducted to examine the effects of the secondary stroke prevention education program to inhibit the recurrence of the acute ischemic stroke patients, and to maintain and promote knowledge about stroke, self-efficacy and self-care. Method: This study was designed to take a quasi-experimental pre- and post-test with the nonequivalent control group. The experimental group consists of 20 patients and control group consists of 20 patients. The experimental group was applied the secondary stroke prevention education program. In order to verify the effects of the secondary stroke prevention education program, knowledge about stroke, self-efficacy and self-care scale were measured before the intervention and 4 weeks, 12 weeks after discharge. The tools for measuring knowledge about stroke, self-efficacy and self-care are developed by the researcher. The data was analyzed by SPSS win 10.0 program using $x^2-test$, Fisher's Exact Test, t-test, Kolmogorov-Smirnov Z, and Repeated Measures ANOVA. Result: There was a statistically significant difference in knowledge about stroke (F=4.021, p=.026), self-efficacy(F=6.096, p=.018), and self-care(F=8.026, p=.007) between the experimental and the control group after intervention. Conclusion: It is considered that the program can be used as an effective nursing intervention in clinical practice.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.17
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• pp.7727-7730
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• 2015

Aims: To identify deficiencies in the knowledge of general medical (GMPs) and dental practitioners (GDPs) regarding early detection of oral cancer, to compare differences between subgroups, and to identify educational needs for continuing education courses on this subject. Materials and Methods: 165 GDPs and 165 GMPs were directly interviewed to assess their knowledge about oral cancer using a pre-tested survey. Knowledge scores were generated from correct responses of participants to factual questions about oral cancer. Results: Few participants (15.2% of GDPs and 12.8% of GMPs) reported that they attended any continuing education courses on oral cancer during their professional career. Most participants (81.6% of GDPs and 86.3% of GMPs) admitted that their knowledge about oral cancer was not up to date and that they would need to attend continuing education courses on oral cancer if available. A few significant differences were identified between groups regarding knowledge about risk factors, clinical presentations and diagnostic techniques but the overall knowledge scores showed no significant difference between GMPs and GDPs. Conclusions: The present study identified several deficiencies in the knowledge of GMPs and GDPs regarding risk factors, clinical presentations, and diagnostic techniques of oral cancer. Interventions to correct these defects through properly designed continuing education courses are required.