• KOREAN JOURNAL OF CROP SCIENCE
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• v.47 no.4
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• pp.301-304
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• 2002

The variation of alternative and cytochrome respiration during ripening in rice leaves (Oryza sativa L. cv. Takanari) was examined. The capacity of both respiration pathway was measured by inhibitor titration method using gas-phase oxygen electrodes. The alternative respiration rate decreased from 31.3% of the total respiration rate at around heading to 11.7% at 34 days after heading in the first fully expanded leaf from the top, and further to 6.4 % at 34 days after heading in the fourth leaf from the top. In contrast, the proportion of cytochrome respiration to total respiration increased with leaf senescence. The possible cause of alternative respiration as either an increase in inefficient respiration or a decrease in growth efficiency during ripening was discussed.

• BMB Reports
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• v.45 no.6
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• pp.342-347
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• 2012

Plant mitochondria possess alternative respiratory pathways mediated by the type II NAD(P)H dehydrogenases and alternative oxidases. Here, E3 SUMO ligase was shown to regulate alternative respiratory pathways and to participate in the maintenance of carbon and nitrogen balance in Arabidopsis. The transcript abundance of the type II NAD(P)H dehydrogenases NDA2 and NDB2 and alternative oxidases AOX1a and AOX1d genes was low in siz1-2 mutants compared to that in wild-type. The addition of nitrate or ammonium resulted in a decrease or an increase in the expression of the same gene families, respectively, in both wild-type and siz1-2 mutants. The amount of free sugar (glucose, fructose and sucrose) was lower in siz1-2 mutants than that in wild-type. These results indicate that low nitrate reductase activity due to the AtSIZ1 mutation is correlated with an overall decrease in alternative respiration and with a low carbohydrate content to maintain the carbon to nitrogen ratio in siz1-2 mutants.

• Proceedings of the Korean Biophysical Society Conference
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• 2001.06a
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• pp.42-42
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• 2001

Candida albicans possess cyanide-resistant respiratory pathway, which is mediated by alternative oxidase. The activity of alternative oxidase has been found to be dependent on several regulatory mechanisms. In order to investigate the influence of D-erythroascorbic acid on respiration of C. albicans, the respiratory activity of the cells was measured with oxygen monitor. ALO1 is known to encode D-arabinono-1,4-lactone oxidase that catalyses the final step of D-erythroascorbic acid biosynthesis in C. albicans.(omitted)

• Journal of Microbiology and Biotechnology
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• v.26 no.3
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• pp.627-636
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• 2016

The causative agent of pandemic cholera, Vibrio cholerae, infects the anaerobic environment of the human intestine. Production of cholera toxin (CT), a major virulence factor of V. cholerae, is highly induced during anaerobic respiration with trimethylamine N-oxide (TMAO) as an alternative electron acceptor. However, the molecular mechanism of TMAO-stimulated CT production is not fully understood. Herein, we reveal that CT production during anaerobic TMAO respiration is affected by glucose fermentation. When the seventh pandemic V. cholerae O1 strain N16961 was grown with TMAO and additional glucose, CT production was markedly reduced. Furthermore, an N16961 Δcrp mutant, devoid of cyclic AMP receptor protein (CRP), was defective in CT production during growth by anaerobic TMAO respiration, further suggesting a role of glucose metabolism in regulating TMAO-mediated CT production. TMAO reductase activity was noticeably decreased when grown together with glucose or by mutation of the crp gene. A CRP binding region was identified in the promoter region of the torD gene, which encodes a structural subunit of the TMAO reductase. Gel shift assays further confirmed the binding of purified CRP to the torD promoter sequence. Together, our results suggest that the bacterial ability to respire using TMAO is controlled by CRP, whose activity is dependent on glucose availability. Our results reveal a novel mechanism for the regulation of major virulence factor production by V. cholerae under anaerobic growth conditions.

• The Korean Journal of Pesticide Science
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• v.4 no.3
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• pp.52-59
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• 2000

A rapid assay to determine respiration inhibition of Saccharomyces cerevisiae by chemicals was developed. S. cerevisiae was harvested with two different liquid media, yeast extract-peptone-dextrose (YPD) medium capable of occurring both glucose fermentation and mitochondrial respiration, and non-fermentable carbon-yeast extract (NFY) medium capable of occurring respiration only Wells in 96-well plate were loaded with each cell suspension and various concentrations of 46 fungicides with various modes of action. n NFY medium, the non-fermentable carbon source, ethanol (NFY-E medium), glycerol (NFY-G medium) or lactate (NFY-L medium), was used. After incubation for $1{\sim}3$ days, minimum inhibitory concentrations (MICs) of the chemicals were recorded in the media. Of the 46 inhibitors employed in this study, four inhibitors of fungal respiration by blockage of electron flux in the mitochondrial respiratory chain, azoxystrobin, kresoxim-methyl, metominostrobin, and trifloxystrobin, exhibited strong antifungal activity in all of NFY media, but no activity in YPD medium. In contrast to this, five N-trihalomethylthio fungicides showed much stronger antifungal activities in YPD medium than three NFY media. Eleven fungicides inhibited growth of S. cerevisiae in all media and the other 26 fungicides showed no antifungal activity in all media. Thus, our rapid and efficient in vitro method can be considered as an alternative assay system for respiration inhibitor.

• Food Science and Biotechnology
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• v.14 no.2
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• pp.181-184
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• 2005

Effects of irradiation and fumigation on disinfestation and quality attributes of chestnuts during storage were studied. Fresh chestnuts were exposed to gamma irradiation (0-10 kGy) and methyl bromide (MeBr) under commercial conditions and stored at different temperatures for 6 months. Pest of quarantine importance for chestnuts, Curculio sikkimensis Heller showed 100% mortality by MeBr on 3rd day after fumigation and by irradiation at 0.5 kGy in about 3 weeks at $23{\pm}0.5^{\circ}C$. Respiration rates of samples one day after treatments increased in proportion to irradiation dose. Respiration pattern of MeBr group was equal to that of 10 kGy-group. Both MeBr and irradiation at 0.25 kGy or higher showed 100% inhibition of sprouting during storage at $5^{\circ}C$ for 6 months. Flesh firmness was significantly reduced by MeBr or irradiation over 5 kGy (p<0.05) 1 day after treatments. MeBr fumigation resulted in appreciable decrease in flesh weight, reducing sugar and ascorbic acid contents (p<0.05), as compared to irradiated samples. Irradiation at 0.5 kGy was effective as alternative to MeBr in controlling pests while maintaining overall quality of fresh chestnuts during storage.

• Journal of The Korean Association For Science Education
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• v.29 no.4
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• pp.463-476
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• 2009

The purpose of this research was to find out if the analogical role-playing class activity had an effect on the students' academic achievements on cellular respirations as well as their science learning motivation for those who took part in the cellular respiration. To examine the effects of applying the activity, the research was conducted targeting a high school with humanities and social sciences courses, located in Busan. The target was specified as two classes that had selected a Biology II class, with one class (27 students) set as the test group and the other class (28 students) set as the control group. The conclusion drawn from this research was as follows: First, it seemed that the analogical role-playing activity helped the students to take their own parts in cellular respiration and gave them an opportunity to explain the concepts through direct physical activities, enhancing their academic achievements. Second, it was concluded that as the students found confidence and relevance in scientific knowledge as well as obtained a sense of accomplishment, the analogical role-playing class activity increased their level of satisfaction and their science learning motives. Third, as a result of the interviews on the change of the concept, students expressed some dissatisfaction over the new concept, and thought of the analogical role-playing activity as an intelligible alternative. It appeared that the alternative was plausible and fruitful.

• Journal of Advanced Navigation Technology
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• v.25 no.4
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• pp.305-312
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• 2021

Even though various types of sensors are being used for security applications, radar sensors are being suggested as an alternative due to the privacy issues. Among those radar sensors, PD radar has high-complexity receiver, but, FMCW radar requires fewer resources. However, FMCW has disadvantage from the use of 2D-FFT which increases the complexity, and it is difficult to distinguish people from objects those are stationary. In this paper, we present the design and the implementation results of the radar signal processor (RSP) that can distinguish between people and object by respiration measurement using phase estimation without 2D-FFT. The proposed RSP is designed with Verilog-HDL and is implemented on FPGA device. It was confirmed that the proposed RSP includes 6,425 LUT, 4,243 register, and 12,288 memory bits with 92.1% accuracy for target's breathing status.

• Journal of Sensor Science and Technology
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• v.27 no.1
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• pp.6-12
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• 2018

In this paper, a 32-variable pulse position modulation (32-VPPM) scheme is proposed to support a red-green-blue light-emitting-diode (RGB-LED)-based optical camera communication (OCC) system. Our proposed modulation scheme is designed to enhance the OCC data transmission rate, which is targeted for the wearable biomedical data monitoring system. The OCC technology has been utilized as an alternative solution to the radio frequency (RF) wireless system for long-term self-healthcare monitoring. Different biomedical signals, such as electrocardiograms, photoplethysmograms, and respiration signals are being monitored and transmitted wirelessly from the wearable biomedical device to the smartphone receiver. A common 30 frames per second (fps) smartphone camera with a CMOS image sensor is used to record a transmitted optical signal. Moreover, the overall proposed system architecture, modulation scheme, and data demodulation are discussed in this paper. The experimental result shows that the proposed system is able to achieve > 9 kbps using only a common smartphone camera receiver.

• Proceedings of the Korean Society for Emotion and Sensibility Conference
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• 2000.11a
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• pp.81-87
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• 2000

Beat-to-beat changes in heart period (heart period variability, HPV) are mediated by fluctuations in autonomic activity. Spectral analysis is used to quantify such fluctuations in the range of 0.15-0.40 Hz (high frequency, HF), which are influenced primarily by parasympathetic factors. These fluctuations are often referred to as RSA (respiratory sinus arrhythmia), the physiological phenomenon extracted by spectral analysis and other methods including histograms of heart rate ( HR), deviations of HR etc. Respiratory sinus arrhythmia indexing with peak-to-valley method suggested by Grossman et at., (1981) yields a simple range statistic and is quantified on breath-by-breath basis, thus being quite sensitive and less dependent on recording time as compared to spectral analysis. It is strongly recommended to use at least 1 min epoch to asses HF component of HPV and at least 2 min fer low frequency (LF) of HPV and even 5 min far valid clinical assessment. Peak-to-valley statistic is limited to RSA index only, but has its pragmatic advantages. Most important is possibility of its application far relatively small epoch analysis. We used short periods (20,30, 40 sec only) and off-line analysis of RSA using ECG and respiration curve this method of assessment and proved that this method is more practically effective. The RSA index was not so far dependent on respiration pattern differences and reflected actual vagal control of HR and were accompanied by low HR under some high stress conditions and in an aversive affective visual stimulation experiments. Another factor that might modulate cardiac chronotropic response is the interaction of sympathetic and parasympathetic inputs on sino-atrial (SA) node level, because responses to vagal influences are known to be proportional to ongoing sympathetic activity, that is so called accentuated antagonism. Since sympathetic outflow (increment of influences on SA) under negative emotions or stress was high in almost all physiological responses, vagal effects on HR could be therefore potentiated, leading to masking of output cardiac response seen in HPV, In the case of moderate sympathetic activation, on the other hand, autonomic interactions in cardiac control appear to be minimal. Thus RSA index appears to be an effective alternative method to assess and measure spectral HPV.