• Title/Summary/Keyword: Heterogeneous conditions

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Comprehensive review of membranoproliferative glomerulonephritis: spotlighting the latest advances in revised classification and treatment

  • Jeong Yeon Kim
    • Childhood Kidney Diseases
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    • v.27 no.2
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    • pp.64-69
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    • 2023
  • Membranoproliferative glomerulonephritis (MPGN) is a complex group of renal diseases characterized by a specific pattern of glomerular injury that includes thickening of the capillary wall and mesangial expansion, leading to a heterogeneous group of conditions. This review article offers a comprehensive overview of MPGN, its new classification, pathophysiology, diagnostic evaluation, and management options.

Improving the Quality of Response Surface Analysis of an Experiment for Coffee-supplemented Milk Beverage: II. Heterogeneous Third-order Models and Multi-response Optimization

  • Rheem, Sungsue;Rheem, Insoo;Oh, Sejong
    • Food Science of Animal Resources
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    • v.39 no.2
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    • pp.222-228
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    • 2019
  • This research was motivated by our encounter with the situation where an optimization was done based on statistically non-significant models having poor fits. Such a situation took place in a research to optimize manufacturing conditions for improving storage stability of coffee-supplemented milk beverage by using response surface methodology, where two responses are $Y_1$=particle size and $Y_2$=zeta-potential, two factors are $F_1$=speed of primary homogenization (rpm) and $F_2$=concentration of emulsifier (%), and the optimization objective is to simultaneously minimize $Y_1$ and maximize $Y_2$. For response surface analysis, practically, the second-order polynomial model is almost solely used. But, there exists the cases in which the second-order model fails to provide a good fit, to which remedies are seldom known to researchers. Thus, as an alternative to a failed second-order model, we present the heterogeneous third-order model, which can be used when the experimental plan is a two-factor central composite design having -1, 0, and 1 as the coded levels of factors. And, for multi-response optimization, we suggest a modified desirability function technique. Using these two methods, we have obtained statistical models with improved fits and multi-response optimization results with the predictions better than those in the previous research. Our predicted optimum combination of conditions is ($F_1$, $F_2$)=(5,000, 0.295), which is different from the previous combination. This research is expected to help improve the quality of response surface analysis in experimental sciences including food science of animal resources.

Analytical characterization of O3 samples prepared for investigation of tropospheric heterogeneous reactions

  • Kim, Mihyeon;Park, Jong-Ho
    • Analytical Science and Technology
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    • v.35 no.5
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    • pp.212-217
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    • 2022
  • In this study, ozone (O3) samples were prepared for investigating the heterogeneous reactions between O3 and tropospheric aerosols and were characterized by spectroscopic methods. O3 generated from an ozone generator was purified by selective adsorption on refrigerated silica gel, followed by transfer to a sample bulb. The amount of UV light (λ = 256 nm) absorbed by O3 was measured as a function of time at two different temperatures (room temperature and 50 ℃) and under different irradiation conditions. A correlation plot of 1/[O3] versus time showed that O3 decomposition follows the 2nd order reaction rate under a steady-state approximation. The initial concentration of O3, observed rate constants (kobs), and the half-life of O3 in the sample stored at room temperature were determined to be 2.74 [±0.14] × 1016 molecules·cm-3, 4.47 [±0.64] × 10-23 molecules-1·cm3·s-1, and 9.5 [±1.4] days, respectively. The evaluation of O3 stability under various conditions indicated that special care should be taken to prevent the exposure of the O3 samples to hightemperature environment and/or UV radiation. This study established a protocol for the preparation of highly purified O3 samples and confirmed that the O3 samples can be stored for a day after preparation for further experiments.

Local Feature Learning using Deep Canonical Correlation Analysis for Heterogeneous Face Recognition (이질적 얼굴인식을 위한 심층 정준상관분석을 이용한 지역적 얼굴 특징 학습 방법)

  • Choi, Yeoreum;Kim, Hyung-Il;Ro, Yong Man
    • Journal of Korea Multimedia Society
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    • v.19 no.5
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    • pp.848-855
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    • 2016
  • Face recognition has received a great deal of attention for the wide range of applications in real-world scenario. In this scenario, mismatches (so called heterogeneity) in terms of resolution and illumination between gallery and test face images are inevitable due to the different capturing conditions. In order to deal with the mismatch problem, we propose a local feature learning method using deep canonical correlation analysis (DCCA) for heterogeneous face recognition. By the DCCA, we can effectively reduce the mismatch between the gallery and the test face images. Furthermore, the proposed local feature learned by the DCCA is able to enhance the discriminative power by using facial local structure information. Through the experiments on two different scenarios (i.e., matching near-infrared to visible face images and matching low-resolution to high-resolution face images), we could validate the effectiveness of the proposed method in terms of recognition accuracy using publicly available databases.

In-Service Identification of the Heterogeneous Zone in Petrochemical Pipelines by Using Sealed Gamma-Ray Sources $(^{60}Co,\;^{137}Cs)$

  • Kim, Jin-Seop;Jung, Sung-Hee;Kim, Jong-Bum
    • Journal of the Korean Society for Nondestructive Testing
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    • v.26 no.3
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    • pp.169-173
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    • 2006
  • In-service diagnoses of pipeline facilities are important for a systematic maintenance of them. Field applications by using sealed gamma-ray sources $(^{60}Co,\;^{137}Cs)$ were performed to identify the heterogeneous zone in the pipelines of a distillation tower and a flare stack respectively. From the results, the heterogeneous zones in the pipelines were successfully identified. In the case of the pipeline connected to the distillation tower, a vapor pocket was detected in the fluid under hydrodynamic conditions, which could explain the reason for a decrease of the flow rate. In another case, an area with some amount of catalyst deposits was found at the bottom of the gas pipeline which was connected to the flare stack. And these findings provided important information for the process operators. Diagnosis technique by using gamma radiation sources has been proven to be an effective and reliable method for providing information on a media distribution in a facility.

Characteristics of Maltose Formation in Heterogeneous Enzyme Reaction System Utilizing Swollen Extrusion Starch as a Substrate (팽윤 Extrusion 전분을 기질로 한 불균일상 효소반응계에서의 Maltose 생성 반응 특성)

  • Kim, Dong-Sun;Park, Dong-Chan;Cho, Myung-Jin;Lee, Yong-Hyun
    • Microbiology and Biotechnology Letters
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    • v.22 no.3
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    • pp.283-289
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    • 1994
  • The production of maltose utilizing swollen extrusion starch seems to have many technical advantages, such as, high reaction rate and high yield, production of high purity concentrated maltose, and low energy consumption, over the conventional method utilizing liquefied starch. The characteristics of maltose formation in heterogeneous enzyme reaction system comtaining swollen extrusion starch was investigated using fungal $\alpha $-amylase. The influence of extrusion conditions on structure of extruded starch, such as, degree of gelatinization, water absorption index, and water solubility index was analyzed. The relationship between the structural features and maltose forming reaction was investigated, and the result was analyzed in terms of surface reaction of insoluble extruded swollen starch. The characteristics of maltose formation from swollen sxtrusion starch was compared using endo-type fungal $\alpha $-amylase and exo-type $\beta $anylase, and the structural trasformation of extruded starch was also observed to clarify the reaction mechanism.

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Asthma in childhood: a complex, heterogeneous disease

  • Chung, Hai-Lee
    • Clinical and Experimental Pediatrics
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    • v.54 no.1
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    • pp.1-5
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    • 2011
  • Asthma in childhood is a heterogeneous disease with different phenotypes and variable clinical manifestations, which depend on the age, gender, genetic background, and environmental influences of the patients. Several longitudinal studies have been conducted to classify the phenotypes of childhood asthma, on the basis of the symptoms, triggers of wheezing illness, or pathophysiological features of the disease. These studies have provided us with important information about the different wheezing phenotypes in young children and about potential mechanisms and risk factors for the development of chronic asthma. The goal of these studies was to provide a better insight into the causes and natural course of childhood asthma. It is well-known that complicated interactions between genes and environmental factors contribute to the development of asthma. Because childhood is a period of rapid growth in both the lungs and the immune system, developmental factors should be considered in the pathogenesis of childhood asthma. The pulmonary system continues to grow and develop until linear growth is completed. Longitudinal studies have reported significant age-related immune development during postnatal early life. These observations suggest that the phenotypes of childhood asthma vary among children and also in an individual child over time. Improved classification of heterogeneous conditions of the disease will help determine novel strategies for primary and secondary prevention and for the development of individualized treatment for childhood asthma.