• Title/Summary/Keyword: aberrations

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Thermo-optical Analysis and Correction Method for an Optical Window in Low Temperature and Vacuum

  • Ruoyan Wang;Ruihu Ni;Zhishan Gao;Lingjie Wang;Qun Yuan
    • Current Optics and Photonics
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    • v.7 no.2
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    • pp.213-221
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    • 2023
  • The optical window, as a part of the collimator system, is the connector between the outside light source and the optical system inside a vacuum tank. The temperature and pressure difference between the two sides of the optical window cause not only thermoelastic deformation, but also refractive-index irregularities. To suppress the influence of these two changes on the performance of the collimator system, thermo-optical analysis is employed. Coefficients that characterize the deformations and refractive-index distributions are derived through finite-element analysis, and then imported into the collimator system using a user-defined surface in ZEMAX. The temperature and pressure difference imposed on the window seriously degrade the system performance of the collimator. A decentered and tilted lens group is designed to correct both field aberrations and the thermal effects of the window. Through lens-interval adjustment of the lens group, the diffraction-limited performance of the collimator can be maintained with a vacuum level of 10-5 Pa and inside temperature ranging from -100 ℃ to 20 ℃.

Optical Design and Tolerance Analysis for UVO-Multiband Polarizing Imager System

  • Han, Jimin;Chang, Seunghyuk;Park, Woojin;Lee, Sunwoo;Ahn, Hojae;Kim, Geon Hee;Lee, Dae-Hee;Pak, Soojong
    • The Bulletin of The Korean Astronomical Society
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    • v.45 no.1
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    • pp.68.2-68.2
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    • 2020
  • UVO-Multiband Polarizing Imager System (UVOMPIS) is an ultraviolet to visible light multi-wavelength polarization/imaging system for Compact Advanced Satellite. We developed Linear Astigmatism Free-Three Mirror System (LAF-TMS) D200F2 as an optical system of UVOMPIS which has an entrance pupil diameter of 200 mm, a focal ratio of 2, a field of view of 2° × 4°. LAF-TMS is a confocal off-axis reflecting telescope system that removes linear astigmatism, and its all mirrors (M1, M2, M3) are optimized with the freeform surface to reduce high-order aberrations. Through the sensitivity analysis and Monte-Carlo simulation as the tolerance analysis, we can confirm the feasibility of the system, relatively sensitive parameters (tilt, decenter, despace, surface RMS error), and considerations for optomechanical design. From the sensitivity analysis, we can discover the relatively sensitive optical alignment parameters to a single perturbation. Further more, in the monte-carlo simulation, we investigate the minimum tolerance budget satisfying the required optical performance and whether the tolerance range is satisfied within manufacturing error.

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Prefrontal Cortex Activation during Diaphragmatic Breathing in Women with Fibromyalgia: An fNIRS Case Report

  • Hyunjoong Kim;Jihye Jung;Seungwon Lee
    • Physical Therapy Rehabilitation Science
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    • v.12 no.3
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    • pp.334-339
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    • 2023
  • Objective: The present study is designed to delve deeper into the realm of fibromyalgia (FM) symptom management by investigating the effects of diaphragmatic breathing on the prefrontal cortex (PFC) in women diagnosed with FM. Using functional near-infrared spectroscopy (fNIRS), the study aims to capture real-time PFC activation patterns during the practice of diaphragmatic breathing. The overarching objective is to identify and understand the underlying neural mechanisms that may contribute to the observed clinical benefits of this relaxation technique. Design: A case report Methods: To achieve this, a twofold approach was adopted: First, the patient's breathing patterns were meticulously examined to detect any aberrations. Following this, fNIRS was employed, focusing on the activation dynamics within the PFC. Results: Our examination unveiled a notable breathing pattern disorder inherent to the FM patient. More intriguingly, the fNIRS analysis offered compelling insights: the ventrolateral prefrontal cortex (VLPFC) displayed increased activation. In stark contrast, regions of the anterior prefrontal cortex (aPFC) and orbitofrontal cortex (OFC) manifested decreased activity, especially when benchmarked against typical activations seen in healthy adults. Conclusions: These findings, derived from a nuanced examination of FM, underscore the condition's multifaceted nature. They highlight the imperative to look beyond conventional symptomatology and appreciate the profound neurological and physiological intricacies that define FM.

Effects of Ginseng Protein on Relative Survival and Chromosome Aberration of UV Irradiated Cells

  • Kim, Choon-Mi;Park, So-Young
    • Archives of Pharmacal Research
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    • v.11 no.3
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    • pp.225-229
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    • 1988
  • A ginseng protein fraction which has been reported to have radiation protective effect was purified from Korean ginseng and its effects on relative survival and chromosome aberration were studied in UV irradiated CHO-K1 cells. When the protein fraction $(100\;{\mu}g/ml)$ was added to the cells before UV irradiation at 4\;J/$m^2$,, the survival rates were increased to 53.8% from 40.6% in control. Addition of the protein $(100\;{\mu}g/ml)$ after UV irradiation at 4 and $8\;J/m^2$ raised the rates to 85.4 and 24.0% from 79.2 and 11.5% in control, respectively. When the ginseng protein $(800\;{\mu}g/ml)$ was added to the cells exposed to UV light at 10, 20, $30\;J/m^2$, the frequencies of chromosome aberration (CA) were reduced significantly to almost same level regardless of the UV dose increment and there was no significant difference between pre- and post-treatment. When the concentration of ginseng protein was increased from 200 to $800\;{\mu}g/ml$, at UV dose of 10, 20, $30\;J/m^2$ each, the CA frequencies were decreased consistently as the dose of ginseng protein increased, at all UV doses tested. Similar effects were observed in both cases of pre- and post-treatment. The data suggest that the protein may reduce cell damage caused by UV light, especially damage to DNA molecule, or play a role in repair processes of damaged DNA, to increase cell survival and reduce chromosome aberrations.

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Pharmacological and Toxicological review of Yukmijihwang-tang(Hwan) (육미지황탕(환)의 약리와 독성에 대한 문헌고찰)

  • Park, Yeong-Chul;Kim, Jong-Bong;Kook, Yoon-Boom;Lee, Sun-Dong
    • Herbal Formula Science
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    • v.20 no.1
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    • pp.13-24
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    • 2012
  • Objectives : Yukmijihwang-tang(Wan), a well-known formula for invigorating yin-particular kidney yin, was first recorded in "Xiao er Yao Zheng Zhi Jue", consisting of Radix Rehmanniae Preparata, Fructus Macrocarpii, Rhizoma Dioscoreae Oppositae, Poria, Rhizoma Alismatis and Cortex Moutan Radicis with dose proportion of 8:4:4:3:3:3. Although clinical trials have been lacking, various pharmacological actions for Yukmijihwang-tang has been identified newly using animal models. In addition, it was reported that Yukmijihwang-tang increases structural chromosome aberrations significantly in Chinese hamster lung cells. In this article, it is purposed that new studies for pharmacology and toxicology of Yukmijihwang-tang are reviewed. Insight into new studies of Yukmijihwang-tang at the cellular and animal levels will enhance our understanding of Yukmijihwang-tang against various diseases will provide new tools to diagnose and treat patients. Methods : Recent researches for Yukmijihwang-tang were reviewed and summarized in terms of pharmacological action and toxicity. All sources for review were based on recent studies loaded on data base of web sites such as Science Direct and National Center for Biotechnology Information. Results and Conclusions : Recently, reports showed that YMJ had antiaging effects, antioxidant and free radical scavenging activities, anti-renal hypertension and prevented tumors, and diabetes mellitus. However, there is little information on its safety except general toxicity, acute and sub-chronic oral toxicity, or genotoxicity. In addition, clinical trial for Yukmijihwang-tang was limited even though Yukmijihwang-tang has been used extensively in Korean traditional medicine. Thus, further studies are necessary to focus on safety evaluation and clinical trial for Yukmijihwang-tang.

Evaluation of Effects of Metformin in Primary Ovarian Cancer Cells

  • Patel, Seema;Singh, Neeta;Kumar, Lalit
    • Asian Pacific Journal of Cancer Prevention
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    • v.16 no.16
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    • pp.6973-6979
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    • 2015
  • Background: Ovarian cancer is the third most common cause of cancer in Indian women. Despite an initial 70-80% response rate, most patients relapse within 1-2 years and develop chemoresistance. Hence, identification or repositioning of drugs to resensitise ovarian cancer cells to existing chemotherapy is needed. Traditionally immortalized cell lines have been used in research, but these may contain genetic aberrations and chromosomal abnormalities serving as poor indicators of normal cell phenotype and progression of early-stage disease. The use of primary cells, maintained for only short periods of time in vitro, may serve as the best representative for studying in vivo conditions of the tissues from which they are derived. In this study we have attempted to evaluate the effect of metformin (an antidiabetic drug) in primary ovarian cancer cells because of its promising effect in other solid tumours. Materials and Methods: Primary cultures of epithelial ovarian cancer cells established from ascitic fluid of untreated ovarian cancer patients were used. The cells were treated with metformin at doses standardized by MTT assay and its ability to induce apoptosis was studied. The cells were analysed for apoptosis and apoptosis related proteins by flow cytometry and western blotting respectively. Results: Metformin induced apoptosis in ovarian cancer cells, provoking cell cycle arrest in the G0/G1 and S phase. It induced apoptosis in ovarian cancer cells by, down-regulating Bcl-2 and up-regulating Bax expression. Conclusions: Metformin was able to induce apoptosis in primary ovarian cancer cells by modulating the expression of Bcl-2 family proteins. These data are relevant to ongoing translational research efforts exploring the chemotherapeutic potential of metformin.

The Similarities and Differences between Intracranial and Spinal Ependymomas : A Review from a Genetic Research Perspective

  • Lee, Chang-Hyun;Chung, Chun Kee;Ohn, Jung Hun;Kim, Chi Heon
    • Journal of Korean Neurosurgical Society
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    • v.59 no.2
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    • pp.83-90
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    • 2016
  • Ependymomas occur in both the brain and spine. The prognosis of these tumors sometimes differs for different locations. The genetic landscape of ependymoma is very heterogeneous despite the similarity of histopathologic findings. In this review, we describe the genetic differences between spinal ependymomas and their intracranial counterparts to better understand their prognosis. From the literature review, many studies have reported that spinal cord ependymoma might be associated with NF2 mutation, NEFL overexpression, Merlin loss, and 9q gain. In myxopapillary ependymoma, NEFL and HOXB13 overexpression were reported to be associated. Prior studies have identified HIC-1 methylation, 4.1B deletion, and 4.1R loss as common features in intracranial ependymoma. Supratentorial ependymoma is usually characterized by NOTCH-1 mutation and p75 expression. TNC mutation, no hypermethylation of RASSF1A, and GFAP/NeuN expression may be diagnostic clues of posterior fossa ependymoma. Although MEN1, TP53, and PTEN mutations are rarely reported in ependymoma, they may be related to a poor prognosis, such as recurrence or metastasis. Spinal ependymoma has been found to be quite different from intracranial ependymoma in genetic studies, and the favorable prognosis in spinal ependymoma may be the result of the genetic differences. A more detailed understanding of these various genetic aberrations may enable the identification of more specific prognostic markers as well as the development of customized targeted therapies.

A study on Genotoxicity Test of Hyeong-gae-yeon-gyo-tang extract (형개연교탕(荊芥連翹湯) 추출물의 유전독성(遺傳毒性) 평가)

  • Jee, Seon-Young;Hwang, Sun-Yi;Lee, Jong-Rok;Kim, Sang-Chan
    • The Korea Journal of Herbology
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    • v.22 no.4
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    • pp.287-300
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    • 2007
  • Objectives : The genotoxicity of extract of "Hyeonggaeyeongyotang", a polyherbal formula has been used as a tonic agents in oriental medicine was tested. Methods : Extract of "Hyeonggaeyeongyotang" was tested by In Vitro Chromosome Aberration Test, Bacterial Reverse Mutation Assay and Micronucleus test according to OECD Guidelines and KFDA Guidelines [2005-60]. Results : The obtained results were as follows: 1. Chromosome Aberration Test: No significant changes in the number of aberrant metaphases having structural and number of aberrations were detected in all concentrations of "Hyeonggaeyeongyotang" extracts treated in this study. 2. Bacterial Reverse Mutation Assay: No significant increases in the number of revertant colonies compared to its negative control were detected in all concentrations of "Hyeonggaeyeongyotang" extracts treated in this study against all 5 strains except for $50{\mu}g/ml$ treated group where significantly decreases in colony numbers were detected agains all five strains used in this study as pharmacological effects not genotoxicity. 3. Micronucleus test: No significant changes in the number of micronucleated polychromatic erythrocytes among 2000 polychromatic erythrocytes compared to negative control were detected in all "Hyeonggaeyeongyotang" extracts-dosing groups tested. Conclusions : From above-mentioned results, it is concluded that "Hyeonggaeyeongyotang" extracts have not any genotoxicity against In Vitro Chromosome Aberration Test, Bacterial Reverse Mutation Assay and Micronucleus test.

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Evaluation of the Genetic Toxicity of Synthetic Chemicals [XII] -in vitro Chromosomal Aberration Assay with 11 Chemicals in Chinese Hamster Lung Fibroblast-

  • Ryu, Jae-Chun;Kim, Youn-Jung
    • Environmental Mutagens and Carcinogens
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    • v.24 no.2
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    • pp.99-107
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    • 2004
  • The validation of many synthetic chemicals that may pose a genetic hazard in our environment is of great concern at present. Since these substances are not limited to the original products, and enter the environment, they have become widespread environmental pollutants, thus leading to a variety of chemicals that possibly threaten the public health. In this respect, the regulation and evaluation of the chemical hazard playa very important role to environment and human health. The clastogenicity of 11 synthetic chemicals was evaluated in Chinese hamster lung (CHL) fibroblast in vitro. Benzoyl chloride (CAS No. 98-88-4) induced chromosomal aberrations with statistical significance at the concentration of 31-123 $\mug/ml$ and 43 $\mug/ml$ in the absence and presence of S-9 metabolic activation system, respectively. 2-Propyn-l-o1 (CAS No. 107-19-7) and 2-Phenoxy ethanol (CAS No. 122-99-6) revealed clastogenicity only at the highest concentration in the presence of S-9 mixture. However, 1-naphthol (CAS No. 90-15-3) which is one of the most cytotoxic chemical among 11 chemicals tested revealed no clastogenicity both in the presence and absence of S-9 metabolic activation system. From the results of chromosomal aberration assay with 11 synthetic chemicals in CHL fibroblast in vitro, Benzoyl chloride (CAS No. 98-88-4), 2-Propyn-l-01 (CAS No. 107-19-7) and 2-Phenoxy ethanol (CAS No. 122-99-6) revealed positive clastogenic results in this study.

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Neurobehavioural Changes and Brain Oxidative Stress Induced by Acute Exposure to GSM900 Mobile Phone Radiations in Zebrafish (Danio rerio)

  • Nirwane, Abhijit;Sridhar, Vinay;Majumdar, Anuradha
    • Toxicological Research
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    • v.32 no.2
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    • pp.123-132
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    • 2016
  • The impact of mobile phone (MP) radiation on the brain is of specific interest to the scientific community and warrants investigations, as MP is held close to the head. Studies on humans and rodents revealed hazards MP radiation associated such as brain tumors, impairment in cognition, hearing etc. Melatonin (MT) is an important modulator of CNS functioning and is a neural antioxidant hormone. Zebrafish has emerged as a popular model organism for CNS studies. Herein, we evaluated the impact of GSM900MP (GSM900MP) radiation exposure daily for 1 hr for 14 days with the SAR of 1.34W/Kg on neurobehavioral and oxidative stress parameters in zebrafish. Our study revealed that, GSM900MP radiation exposure, significantly decreased time spent near social stimulus zone and increased total distance travelled, in social interaction test. In the novel tank dive test, the GSM900MP radiation exposure elicited anxiety as revealed by significantly increased time spent in bottom half; freezing bouts and duration and decreased distance travelled, average velocity, and number of entries to upper half of the tank. Exposed zebrafish spent less time in the novel arm of the Y-Maze, corroborating significant impairment in learning as compared to the control group. Exposure decreased superoxide dismutase (SOD), catalase (CAT) activities whereas, increased levels of reduced glutathione (GSH) and lipid peroxidation (LPO) was encountered showing compromised antioxidant defense. Treatment with MT significantly reversed the above neurobehavioral and oxidative derangements induced by GSM900MP radiation exposure. This study traced GSM900MP radiation exposure induced neurobehavioral aberrations and alterations in brain oxidative status. Furthermore, MT proved to be a promising therapeutic candidate in ameliorating such outcomes in zebrafish.