• Title/Summary/Keyword: dual-frequency

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New therapeutic approach with extracellular vesicles from stem cells for interstitial cystitis/bladder pain syndrome

  • Dayem, Ahmed Abdal;Song, Kwonwoo;Lee, Soobin;Kim, Aram;Cho, Ssang-Goo
    • BMB Reports
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    • v.55 no.5
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    • pp.205-212
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    • 2022
  • Interstitial cystitis/bladder pain syndrome (IC/BPS) is a debilitating chronic disorder characterized by suprapubic pain and urinary symptoms such as urgency, nocturia, and frequency. The prevalence of IC/BPS is increasing as diagnostic criteria become more comprehensive. Conventional pharmacotherapy against IC/BPS has shown suboptimal effects, and consequently, patients with end-stage IC/BPS are subjected to surgery. The novel treatment strategies should have two main functions, anti-inflammatory action and the regeneration of glycosaminoglycan and urothelium layers. Stem cell therapy has been shown to have dual functions. Mesenchymal stem cells (MSCs) are a promising therapeutic option for IC/BPS, but they come with several shortcomings, such as immune activation and tumorigenicity. MSC-derived extracellular vesicles (MSC-EVs) hold numerous therapeutic cargos and are thus a viable cell-free therapeutic option. In this review, we provide a brief overview of IC/BPS pathophysiology and limitations of the MSC-based therapies. Then we provide a detailed explanation and discussion of therapeutic applications of EVs in IC/BPS as well as the possible mechanisms. We believe our review will give an insight into the strengths and drawbacks of EV-mediated IC/BPS therapy and will provide a basis for further development.

Double burden of malnutrition in ethnic minority school-aged children living in mountainous areas of Vietnam and its association with nutritional behavior

  • Truong, Duong Thuy Thi;Tran, Trang Huyen Thi;Nguyen, Tam Thanh Thi;Tran, Van Hong Thi
    • Nutrition Research and Practice
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    • v.16 no.5
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    • pp.658-672
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    • 2022
  • BACKGROUND/OBJECTIVES: Although children of ethnic minority groups are experiencing a transition from a predominance of undernutrition to overnutrition, there is little evidence of a dual-malnutrition burden. Therefore, this study examined the double burden of malnutrition among school-aged ethnic minority children living in mountainous areas and its association with their diets. SUBJECTS/METHODS: A cross-sectional study was conducted from September 2019 to March 2020 in 3 mountainous areas of Northern Vietnam among 1,556 ethnic minority school-aged children. The prevalence of under-nutrition (stunting and thinness) and over-nutrition (overweight and obesity) were measured using the WHO 2006 child growth standards (height-for-age and BMI-for-age Z-score). Nutritional practices were evaluated by the frequency of food consumption based on a 4-level scale. RESULTS: The percentage of children with stunting and thinness were 14.0% and 5.4%, respectively, while the figure for overweight/obesity was 9.4%. The factors positively associated with stunting were living in a family with more than 2 children or being Muong/other ethnicities compared to the Tay ethnicity. Children who consumed fish/shrimps/crabs or milk weekly/daily were less likely to be undernourished compared to those who never consumed these foods. By contrast, children who never consumed foods rich in vitamin A precursors and vitamin A and fruit or consumed daily snacks/junk food were more likely to be overweight/obese. CONCLUSIONS: Undernutrition remains a common issue among school-aged children and adolescents of ethnic minority groups, while over-nutrition exists simultaneously. Public health nutrition programs promoting adequate diets and positive lifestyle changes related to nutrition are essential to tackle the double burden of malnutrition among ethnic minority children.

The Roles of Welfare and Hope Between Boss Incivility Experience and Flourishing of Childcare Teachers (보육교사의 상사무례경험과 플로리싱의 관계에서 복지와 희망의 역할)

  • Suk-gyeong, Kim;Hea-yeon, Yun;Kye-Lim, Ahn;Soon-Min, Suh
    • Journal of Industrial Convergence
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    • v.20 no.11
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    • pp.95-104
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    • 2022
  • This study aimed to provide basic data for the promotion of flourishing by analyzing whether welfare and hope mediated and double-mediated in the relationship between boss incivility and flourishing with 400 childcare teachers. The subjects of the survey were collected through offline questionnaires. The data were analysed using SPSS PC+ Win ver. 25.0 and PROCESS macro. Frequency, reliability, correlation, and double mediation effect analysis were performed. As a result of the study, first, experience of incivility from bosses showed a negative correlation with welfare, hope, and flourishing. welfare, hope and flourishing showed a positive correlation with each other. Second, welfare and hope played a double mediating role in the relationship between boss and co-worker incivility and flourishing. Welfare and hope played a role in partially offsetting the negative (-) effect of incivility on flourishing. The conclusion of this study confirmed that the promotion of flourishing can be promoted by using the dual mediating role of welfare and hope.

A study on proportional multiple-resonance controller for harmonic distortion compensation of single phase VSIs (단상 전압 소스 인버터의 고조파 왜곡 보상을 위한 비례 다중 공진 제어기에 관한 연구)

  • Bongwoo Kwak
    • Journal of IKEEE
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    • v.27 no.3
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    • pp.319-326
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    • 2023
  • In this paper, simulation and experimental results are presented, including the implementation of a digital controller for robust output voltage control of a single-phase voltage source inverters (VSIs) and total harmonic distortion (T.H.D.v) analysis. Typically, the VSIs uses a proportional integral (PI) controller for the current controller on the inner loop and a proportional resonant (PR) controller for the voltage controller on the outer loop to control the output voltage. However, non-linear loads still produce high-order odd harmonic distortion. Therefore, in this paper, a proportional multiple resonance (PMR) controller with a resonance controller for odd harmonic frequencies is proposed to suppress harmonic distortion. Analyze the frequency response of controllers for VSI plants and design PMR controllers. Through simulation, the total harmonic distortion characteristics of the output voltage are compared and verified when PI and PMR are used as voltage controllers. Both linear and non-linear loading conditions were considered. Finally, the effectiveness of the PMR controller was demonstrated by applying it to a 3kW VSIs prototype.

Carrier Phase Based Cycle Slip Detection and Identification Algorithm for the Integrity Monitoring of Reference Stations

  • Su-Kyung Kim;Sung Chun Bu;Chulsoo Lee;Beomsoo Kim;Donguk Kim
    • Journal of Positioning, Navigation, and Timing
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    • v.12 no.4
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    • pp.359-367
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    • 2023
  • In order to ensure the high-integrity of reference stations of satellite navigation system, cycle slip should be precisely monitored and compensated. In this paper, we proposed a cycle slip algorithm for the integrity monitoring of the reference stations. Unlike the legacy method using the Melbourne-Wübbena (MW) combination and ionosphere combination, the proposed algorithm is based on ionosphere combination only, which uses high precision carrier phase observations without pseudorange observations. Two independent and complementary ionosphere combinations, Ionospheric Negative (IN) and Ionospheric Positive (IP), were adopted to avoid insensitive cycle slip pairs. In addition, a second-order time difference was applied to the IN and IP combinations to minimize the influence of ionospheric and tropospheric delay even under severe atmosphere conditions. Then, the cycle slip was detected by the thresholds determined based on error propagation rules, and the cycle slip was identified through weighted least square method. The performance of the proposed cycle slip algorithm was validated with the 1 Hz dual-frequency carrier phase data collected under the difference levels of ionospheric activities. For this experiment, 15 insensitive cycle slip pairs were intentionally inserted into the raw carrier phase observations, which is difficult to be detected with the traditional cycle slip approach. The results indicate that the proposed approach can successfully detect and compensate all of the inserted cycle slip pairs regardless of ionospheric activity. As a consequence, the proposed cycle slip algorithm is confirmed to be suitable for the reference station where real time high-integrity monitoring is crucial.

Review of GPS and Galileo Integrity Assurance Procedure (GPS와 Galileo의 무결성 보장 방법 조사)

  • Namkyu Woo;Gihun Nam;Heonho Choi;Jiyun Lee
    • Journal of Positioning, Navigation, and Timing
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    • v.13 no.1
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    • pp.53-61
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    • 2024
  • Global Navigation Satellite Systems are expected to meet system-defined integrity requirements when users utilize the system for safety critical applications. While the guaranteed integrity performance of GPS and Galileo is publicly available, their integrity assurance procedure and related methodology have not been released to the public in an official document format. This paper summarizes the integrity assurance procedures of Global Positioning System (GPS) and Galileo, which were utilized during their system development, through a literature survey of their integrity assurance methodology. GPS Block II assures system integrity using the following methods: continuous performance monitoring and maintenance on Space Segment (SS) and Control Segment (CS), through a cause and effect analysis of anomalies and a failure analysis. In GPS Block III, to achieve more stringent integrity performance, safety requirements are integrated into the system design and development from its starting phase to the final phase. Galileo's integrity performance is provided in the Integrity Support Message (ISM) format, as Galileo utilizes a Dual Frequency Multi Constellation (DFMC) Satellite Based Augmentation System (SBAS) and Advanced Receiver Autonomous Integrity Monitoring (ARAIM) to serve safety critical applications. The integrity performance of Galileo is ensured by using a methodology similar to GPS Block II (i.e. continuous performance monitoring and maintenance on the system). The integrity assurance procedures reviewed in this paper can be utilized for a new satellite navigation system that will be developed in the near future.

Double Mediating Effect of Learning Motivation and Grit between Emotional Intelligence and Learning Engagement in Chinese High School Students (중국 고등학생의 정서지능과 학습몰입의 관계에서 학습동기와 그릿의 이중매개효과)

  • Luo Zhiwen;Gao Runze;Chang Seek Lee
    • Industry Promotion Research
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    • v.9 no.1
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    • pp.213-221
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    • 2024
  • This study aims to determine whether learning motivation and grit mediate in the relationship between emotional intelligence and learning engagement among Chinese high school students. Data were collected through a survey targeting 304 high school students purposively sampled from a high school in China. The collected data was analyzed using SPSS PC+ Win ver. 25.0 and SPSS PROCESS macro ver. 4.2. The statistical methods applied were frequency analysis, reliability analysis, correlation analysis, and dual mediation effect analysis. The conclusion of the study is as follows. First, emotional intelligence, learning motivation, grit, and learning engagement all showed significant positive correlations. Second, high school students' learning motivation and grit double-mediated in the relationship between emotional intelligence and learning engagement. Based on these results, this study proposed a plan to improve high school students' academic engagement by utilizing not only emotional intelligence but also learning motivation and grit.

Prescriptive analysis of liquid gastric digestive solutions (액상형 건위소화제의 방제학적 분석)

  • Hong Seok Lee;Min Ju Kim;Ye Bin Shin;Soo Myeong Kim;Sung Jong Shin;Kyung Hwan Jegal
    • Herbal Formula Science
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    • v.32 no.3
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    • pp.277-296
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    • 2024
  • Objective : Dyspepsia is one of the most common ailments among Koreans, leading to a continuously expanding market for liquid digestive solutions. These products are popular due to their convenience and low risk of side effects. However, there is a lack of research on the basic prescription composition of these ingredients and their precise indications according to Korean Medicine. Methods : Drugs were selected from the Korea Pharmaceutical Information Service website (http://www.health.kr), focusing on oral and liquid products classified under the Ministry of Food and Drug Safety's category of stomach and digestive aids (category 233). Frequency analysis was conducted to determine the occurrence and combinations of herbal ingredients within each product. Additionally, the four properties and five flavors of each product were calculated using their herbal ingredient composition ratios, and Pearson correlation coefficients were employed to verify the linear relationships between the composition ratios of the ingredients. Results : A comparative analysis of 33 liquid digestive medicines revealed that Zingiberis Rhizoma was the most frequently used herb. The most common dual-herb combination was Zingiberis Rhizoma and Citri Unshius Pericarpium, and the most prevalent tri-herb combination was Zingiberis Rhizoma, Citri Unshius Pericarpium, and Cinnamomi Cortex. Pearson correlation coefficient analysis showed a strong positive correlation between the composition ratios of Zingiberis Rhizoma and Cinnamomi Cortex. The analysis of four properties and five flavors indicated that products with warm and bitter flavors were the most common. Conclusions : The most frequently used herbal combination in liquid digestive solutions was Zingiberis Rhizoma, Citri Unshius Pericarpium, and Cinnamomi Cortex. This composition is suitable for treating dyspepsia caused by cold-dampness in the digestive system.

The Design of Broadband Ultrasonic Transducers for Fish Species Identification - Dual Resonance Design of a Ultrasonic Transducer Using a Single Acoustic Matching Layer - (어종식별을 위한 광대역 초음파 변환기의 설계 II - 단일음향정합층을 이용한 이중공진형 변환기의 설계 -)

  • 이대재
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.34 no.1
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    • pp.74-84
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    • 1998
  • A doubly resonant ultrasonic transducer has been designed as an attempt to increase the bandwidth of underwater transducers. The dual resonance conditions were accomplished by attaching a single acoustic matching layer on the front face of a Tonpilz transducer consisted of an aluminum head, a piezoelectric ring, a brass tail and a prestress bolt. A modified Mason's model was used for the performance analysis and the design of transducers, and the constructed transducers were tested experimentally and numerically by changing the impedances and thicknesses of the head, tail and matching layers in the water tank. Two distinct resonance peaks in the transmitting voltage response(TVR) of a developed transducer were observed at 34.3 and 40.4 kHz, respectively, with the difference frequency of 6.1kHz and the center frequency of 37.2kHz. The values of TVR at these frequencies were 136.5 dB re $1\;\muPa/V$ at 34.3 kHz and 136.8 dB re $1\;\muPa/V$ at 40.4 kHz, respectively. Reasonable agreement between the experimental results and the numerical results was achieved. From this result, it is expected that the generation of the distinct resonances at any two desired frequencies can be achieved through the proper choice of the matching layer to provide the impedance transformation between the transducer and the medium.

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An 8b 240 MS/s 1.36 ㎟ 104 mW 0.18 um CMOS ADC for High-Performance Display Applications (고성능 디스플레이 응용을 위한 8b 240 MS/s 1.36 ㎟ 104 mW 0.18 um CMOS ADC)

  • In Kyung-Hoon;Kim Se-Won;Cho Young-Jae;Moon Kyoung-Jun;Jee Yong;Lee Seung-Hoon
    • Journal of the Institute of Electronics Engineers of Korea SD
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    • v.42 no.1
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    • pp.47-55
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    • 2005
  • This work describes an 8b 240 MS/s CMOS ADC as one of embedded core cells for high-performance displays requiring low power and small size at high speed. The proposed ADC uses externally connected pins only for analog inputs, digital outputs, and supplies. The ADC employs (1) a two-step pipelined architecture to optimize power and chip size at the target sampling frequency of 240 MHz, (2) advanced bootstrapping techniques to achieve high signal bandwidth in the input SHA, and (3) RC filter-based on-chip I/V references to improve noise performance with a power-off function added for portable applications. The prototype ADC is implemented in a 0.18 um CMOS and simultaneously integrated in a DVD system with dual-mode inputs. The measured DNL and INL are within 0.49 LSB and 0.69 LSB, respectively. The prototype ADC shows the SFDR of 53 dB for a 10 MHz input sinewave at 240 MS/s while maintaining the SNDR exceeding 38 dB and the SFDR exceeding 50 dB for input frequencies up to the Nyquist frequency at 240 MS/s. The ADC consumes, 104 mW at 240 MS/s and the active die area is 1.36 ㎟.