• Title/Summary/Keyword: free-form

Search Result 1,943, Processing Time 0.028 seconds

Human Lung Insults due Air Pollutant -A Review for Priority Setting in the Research- (대기오염에 의한 폐장조직 손상 -연구방향의 설정을 위한 논의-)

  • 김건열;백도명
    • Journal of environmental and Sanitary engineering
    • /
    • v.7 no.2
    • /
    • pp.95-110
    • /
    • 1992
  • Much progress has been made in understanding the subcellular events of the human lung injuries after acute exposure to environmental air pollutants. Host of those events represent oxidative damages mediated by reactive oxygen species such as superoxide, hydrogen peroxide, and the hydroxy, free radical. Recently, nitric oxide (NO) was found to be endogenously produced by endothelial cells and cells of the reticulo-endothelial system as endothelialderived relaxation factor (EDRF) which is a vasoactive and neurotransmitter substance. Together with superoxide, NO can form another strong oxidant, peroxonitrite. The relative importance of exogenous sources of $N0/N0_2$ and endogenous production of NO by the EDRF producing enzymes in the oxidative stresses to the heman lung has to be elucidated. The exact events leading to chronic irreversible damage are still yet to be known. From chronic exposure to oxidant gases, progressive epithelial and interstitial damages develop. Type I epithelial cells become thicker and cover a smaller average alveolar surface area while thee II cells proliferate instead. Under acute damages, the extent of loss of the alveolar epithelial cell lining, especially type II cells appears to be a good predictor of the ensuing irreversible damage to alveolar compartment. Interstitial matrix undergo remodeling during chronic exposure with increased collagen fibers and interstitial fibroblasts. However, Inany of these changes can be reversed after cessation of exposure. Among chronic lung injuries, genetic damages and repair responses received particular attention in view of the known increased lung cancer risks from exposure to several air pollutants. Heavy metals from foundry emission, automobile traffics, and total suspended particulate, especially polycystic aromatic hydrocarbons have been positively linked with the development of lung cancer. Asbestos in another air pollutant with known risk of lung cancer and mesothelioma, but asbestos fibers are nonauthentic in most bioassays. Studies using the electron spin resonance spin trapping method show that the presence of iron in asbestos accelerates the production of the hydroxy, radical in vitro. Interactions of these reactive oxygen species with particular cellular components and disruption of cell defense mechanisms still await further studies to elucidate the carcinogenic potential of asbestos fibers of different size and chemical composition. The distribution of inhaled pollutants and the magnitude of their eventual effects on the respiratory tract are determined by pollutant-independent physical factors such as anatomy of the respiratory tract and level and pattern of breathing, as well as by pollutant-specific phyco-chemical factors such as the reactivity, solubility, and diffusivity of the foreign gas in mucus, blood and tissue. Many of these individual factors determining dose can be quantified in vitro. However, mathematical models based on these factors should be validated for its integrity by using data from intact human lungs.

  • PDF

Antioxidative Activities of Rhus verniciflua Bark from Different Area (산지별 옻피의 항산화 활성과 옻닭국 기호특성 비교)

  • Park, Sung-Jin;Yang, Byung-Wook;Hahm, Young-Tae;Oh, Deog-Hwan;Kim, Jung-Beom;Yang, Ji-Yun;Kang, Byung-Sun
    • The Korean Journal of Food And Nutrition
    • /
    • v.25 no.3
    • /
    • pp.430-435
    • /
    • 2012
  • The objectives of this study were to form comparisons of total polyphenol compounds, the antioxidant activities and the urushiol contents of lacquer tree(Rhus verniciflua) bark and the sensory properties of chicken soup was made with lacquer tree bark that was cultivated from different cultivation areas; Hamyang, Wonju and China. Total polyphenol contents of Hamyang, Wonju and China were estimated as $375.28{\pm}3.48$, $403.60{\pm}6.6$ and $311.06{\pm}4.99$ mg/g. The total flavonoids contents of Hamyang, Wonju and China were measured as $374{\pm}14.12$, $683.70{\pm}12.64$ and $334.64{\pm}18.40$ mg/g. The total phenolic compounds and flavonoids concentration, DPPH radical scavenging activity, and ABTS radical scavenging of lacquer tree cultivated in Wonju were higher than the others; Hamyang and China. The urushiol content of lacquer tree bark from Hamyang was $4.59{\pm}0.04$ ppm and higher than others. Urushiol was not detected in China lacquer tree bark. Sensory evaluation tests for chicken soup containing lacquer tree bark showed that the scores of Wonju lacquer tree bark chicken soup was highest, however there are no differences between Hamyang, Wonju, and China significantly(p<0.05).

Inservice Elementary Teachers' Perceptions of Teaching Skills and Educational Settings in Implementing a Problem Based Learning Approach (문제중심학습 교수 실행의 능력과 교육 환경에 대한 초등 교사들의 인식)

  • Choi, Hyun-Dong
    • Journal of the Korean earth science society
    • /
    • v.32 no.3
    • /
    • pp.334-345
    • /
    • 2011
  • The purpose of this study was to find out inservice teachers' teaching skills and relevant educational settings that could be applied to an instruction of problem-based learning (PBL). Participants have been instructed PBL teacher training programs and applied PBL into teaching and learning process. Three elementary teachers were selected to participate in the study, and data were collected with semi-structured interviews. The interviews of the teachers in relation to PBL were analyzed by two main topics: (1) the teachers' teaching skills required in PBL and (2) the educational settings in implementing PBL. The results are as follows: First, there is a difficulty involved in the implementation of PBL in that its preparation and teaching process are different from the traditional teaching methodology. However, as a helper who guides the students to self-directed learning in the free and permissible learning environment in which students are motivated to develop their potential effectively, the teachers are to invest their time consistently and to put their efforts into making an effective class in the entire process of PBL. Second, as a method to apply the problem-based learning to the education settings, the teachers must spread the awareness of PBL to fellow teachers, students, their parents and the administrators in education and form the community of the teachers. Most importantly, when the teachers apply PBL in the directly, from the joy of witnessing the changes in the students, they will choose to adopt PBL.

Evaluation of Radical Scavenging and α-Glucosidase Inhibitory Effects of Gallic Acid Reactants Using Polyphenol Oxidase (폴리페놀산화효소를 활용한 Gallic Acid 반응물의 라디칼 소거 및 α-Glucosidase 저해 활성 평가)

  • Jeong, Yun Hee;Kim, Tae Hoon
    • Journal of the Korean Society of Food Science and Nutrition
    • /
    • v.45 no.9
    • /
    • pp.1385-1390
    • /
    • 2016
  • Gallic acid is a representative hydroxybenzoic acid and is found in free form in several plants and in various esterified forms as a part of hydolyzable tannins. Convenient enzymatic transformation of trihydroxylated gallic acid with polyphenol oxidase originating from pear was evaluated to investigate whether polyphenol oxidase can be used as a valuable compound to improve the biological activity of gallic acid. Enzymatic oxidation processing of gallic acid using polyphenol oxidase was carried out for five different reaction times. The antioxidant effects of transformed gallic acid for different reaction times were evaluated via radical scavenging assays using 1,1-diphenyl-2-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radicals. In addition, the anti-diabetic property of the transformed gallic acid was measured based on ${\alpha}$-glucosidase. Gallic acid reacted for 5 h showed significantly higher antioxidant and ${\alpha}$-glucosidase inhibitory activities compared to the tested positive control substances. Biotransformation of simple gallic acid induced by polyphenol oxidase might be responsible for enhancing the biological activity of gallic acid.

INFLUENCE OF DIETARY PROTEIN ON THE FRACTIONATION OF SELENIUM IN THE RUMEN OF SHEEP

  • Serra, A.B.;Serra, S.D.;Fujihara, T.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.9 no.5
    • /
    • pp.557-562
    • /
    • 1996
  • The effects of diets differing in protein content through soybean meal supplementation on ruminal fractionation of selenium (Se) were studied. A $3{\times}3$ Latin square design was used with three Japanese Corriedale wethers (45 kg average body weight), three periods, and three dietary treatment. The three dietary treatments were : Diet 1, without soybean meal supplementation (14% crude protein, CP); Diet 2, with 10% soybean meal supplementation (16.5% CP); and Diet 3, with 20% soybean meal supplementation (19% CP). All the diets had a Se supplementation in the form of sodium selenite at 0.2 mg Se/kg dietary DM. The Se supplement and the concentrate mixture were fed only in the morning before the hay was given. Daily feeding schedule for gay was set at 09:00 and 17:00 h. On the final day of collection period, ruminal fluid samples were obtained at 0.5, 2, 6, 12 and 24 h post-feeding starting at 09:00 h. Total ruminal fluid Se was markedly higher (p<0.05) in Diet 3 than those in Diets 1 and 2 at almost all sampling time except at 24 h. The proportion of Se in soluble protein to the total ruminal Se was higher (p< 0.05) in Diet 3 (40%) followed by Diet 2 (28%) and Diet 1 (21%). The proportion of free inorganic Se to the total ruminal Se was the reverse, especially after two hours where Diet 1 (p<0.05) was higher than the other diets. Bacterial Se was lower (p < 0.05) in Diet 1 than those in Diets 2 and 3 at any sampling time. The highest was observed at 2 h postprandially in all diets with a value of 421, 556, $655{\mu}g/kg$ bacterial DM for Diet 1, 2 and 3, respectively. No differences (p>0.05) were observed on ruminal pH, ammonia and total nolatile fatty acids although increasing protein supplementation tended to decline the ruminal pH and increase ruminal ammonia. This study concludes that increasing dietary protein content by soybean meal supplementation can affect the ruminal Se metabolism.

Inflammatory Breast Cancer: a Single Centre Analysis

  • Gogia, Ajay;Raina, Vinod;Deo, Suryanarayan Vishnu;Shukla, Nootan Kumar;Mohanti, Bidhu Kalyan;Sharma, Daya Nand
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.15 no.7
    • /
    • pp.3207-3210
    • /
    • 2014
  • Background: Inflammatory breast cancer (IBC) is an aggressive form of locally advanced breast cancer characterized by rapidly progressive breast erythema, pain and tenderness, oedema and paeu d'orange appearance. It accounts for 1-3% of all newly diagnosed cases of breast cancer in the west. Data on IBC from India are lacking. The aim of our study was to assess the clinical-pathological parameters and outcome of IBC at, All India Institute of Medical Sciences, a large tertiary care centre. Materials and Methods: We screened 3,650 breast cancer cases registered from January 2004 to December 2012 and found 41 cases of IBC. Data included demographics as well as clinical, radiological and histopathological characteristics, and were collected from clinical case records using the International Classification of Diseases code (C-50). Patients who presented with IBC as a recurrence, or who had a neglected and advanced breast cancer that simulated an IBC were excluded from this study. Results: The median age was 45 years (range 23-66). The median duration of symptoms was 5 months. The American Joint Committee on Cancer stage (AJCC) distribution was Stage III - 26 and IV - 15 patients. Estrogen receptor (ER), progesterone receptor (PR) positivity and human epidermal growth factor receptor 2 (HER2/neu) positivity were 50%, 46% and 60%, respectively. Triple negativity was found in 15% of the cases. All the non metastatic IBC patients received anthracycline and/ or taxane based chemotherapy followed by modified radical mastectomy, radiotherapy and hormonal therapy as indicated. Pathological complete remission rate was 15%. At a median follow-up of 30 months, the 3 year relapse free survival and overall survival were 30% and 40%respectively. Conclusion: IBC constituted 1.1% of all breast cancer patients at our centre. One third of these had metastatic disease at presentation. Hormone positivity and Her2 neu positivity were found in 50% and 60% of the cases, respectively.

The Social Implication of New Media Art in Forming a Community (공동체 형성에 있어서 뉴미디어아트의 사회적 역할에 대한 고찰)

  • Kim, Hee-Young
    • The Journal of Art Theory & Practice
    • /
    • no.14
    • /
    • pp.87-124
    • /
    • 2012
  • This paper focuses on the social implication of new media art, which has evolved with the advance of technology. To understand the notion of human-computer interactivity in media art, it examines the meaning of "cybernetics" theory invented by Norbert Wiener just after WWII, who provided "control and communication" as central components of his theory of messages. It goes on to investigate the application of cybernetics theory onto art since the 1960s, to which Roy Ascott made a significant contribution by developing telematic art, utilizing the network of telecommunication. This paper underlines the significance of the relationship between human and machine, art and technology in transforming the work of art as a site of communication and experience. The interactivity in new media art transforms the viewer into the user of the work, who is now provided free will to make decisions on his or her action with the work. The artist is no longer a godlike figure who determines the meaning of the work, yet becomes another user of his or her own work, with which to interact. This paper believes that the interaction between man and machine, art and technology can lead to various ways of interaction between humans, thereby restoring a sense of community while liberating humans from conventional limitations on their creativity. This paper considers the development of new media art more than a mere invention of new aesthetic styles employing advanced technology. Rather, new media art provides a critical shift in subverting the modernist autonomy that advocates the medium specificity. New media art envisions a new art, which would embrace impurity into art, allowing the coexistence of autonomy and heteronomy, embracing a technological other, thereby expanding human relations. By enabling the birth of the user in experiencing the work, interactive new media art produces an open arena, in which the user can create the work while communicating with the work and other users. The user now has freedom to visit the work, to take a journey on his or her own, and to make decisions on what to choose and what to do with the work. This paper contends that there is a significant parallel between new media artists' interest in creating new experiences of the art and Jacques Ranci$\grave{e}$re's concept of the aesthetic regime of art. In his argument for eliminating hierarchy in art and for embracing impurity, Ranci$\grave{e}$re provides a vision for art, which is related to life and ultimately reshapes life. Ranci$\grave{e}$re's critique of both formalist modernism and Jean-Francois Lyotard's postmodern view underlines the social implication of new media art practices, which seek to form "the common of a community."

  • PDF

The Effect of a Natural Zeolite (Clinoptilolite) on the Performance of Broiler Chickens and the Quality of Their Litter

  • Karamanlis, X.;Fortomaris, P.;Arsenos, G.;Dosis, I.;Papaioannou, D.;Batzios, C.;Kamarianos, A.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.21 no.11
    • /
    • pp.1642-1650
    • /
    • 2008
  • The objective of this study was to assess the effect of clinoptilolite (a natural zeolite) on growth and performance of broilers as well as on the quality of their litter. A total of 5,200 one-day old broiler chickens (Cobb 500) were used in two consecutive rounds lasting 42 days each. The broilers were given free and continuous access to a nutritionally non-limiting diet (in meal form) that was either a basal diet (B) or a 'zeolite diet' (Z; the basal diet supplemented with clinoptilolite at a level of 2%). A $2{\times}2$ factorial design consisted of two feeding treatments (B and Z) and two bedding types, sawdust (S) and sawdust with zeolite (Sz, which was the result of adding $2kg\;zeolite/m^2$), was used. In each round the broilers were randomly assigned to one of four (n = 650), treatment groups: two fed on the basal diet (B) and had bedding of either sawdust (group BS) or sawdust and zeolite (group BSz) and two fed on the Z diet and had as bedding either sawdust (ZS) or sawdust and zeolite (ZSz). Average growth rates were significantly (p<0.05) different between broilers of different groups; broilers that were fed on the 'zeolite diet' (Z) and were placed either in a compartment with sawdust bedding or sawdust bedding and zeolite (ZS and ZSz) as well those that were fed on the basal diet in a compartment with sawdust bedding and zeolite (BSz) grew at a faster rate (p<0.05) compared with those of the control group (BS). The incorporation of NZ in broilers diets and in their bedding material decreased the organic content in litter samples throughout the experimental period. The lowest organic content was recorded in group ZSz where NZ was added in both feed and litter. Mean ammonia concentration (ppm) was significantly higher in group ZS in comparison to groups BSz and ZSz (27.00 vs. 20.55 and 21.71 respectively). The results of this study showed that the incorporation of the clinoptilolite both in feed and into the litter had a positive effect on broiler growth and also on the quality of their litter.

An Implementation of Acoustic Echo Canceller Using Adaptive Filtering in Modulated Lapped Transform Domain (Modulated Lapped Transform 영역에서 적응 필터링을 이용한 음향 반향 제거기의 구현)

  • 백수진;박규식
    • The Journal of the Acoustical Society of Korea
    • /
    • v.22 no.6
    • /
    • pp.425-433
    • /
    • 2003
  • Acoustic Echo Canceller (AEC) is a signal processing system for removing unwanted echo signals in teleconference and hands-free communication. Least mean square (LMS) algorithm is one of the adaptive echo cancellation algorithms and it has been most attractive because of its simplicity and robustness. However, the convergence properties of the LMS algorithm degrade with highly correlated input signals such as speech. For this reason, transform-domain adaptive filtering algorithm was introduced to decorrelate the colored input samples by using the orthogonal transform matrix such as DCT, DFT and then LMS adaptive filtering process is applied. In this paper, we propose a MLT domain adaptive echo canceller base on the MLT (Modulated lapped Transform) orthogonal transform matrix. The proposed algorithm achieves high decorrelation efficiency and fast convergence speed via modulated lapped transform of size 2NXN instead of NXN unitary transform such as DCT, DFT, Hadamad and it is applied to the acoustical echo cancellation system. Form the computer simulation with both synthesis and real speech, the proposed MLT domain adaptive echo canceller shows approximately twice faster convergence speed and 20∼30 ㏈ ERLE improvements over the DCT frequency domain acoustic echo cancellation system.

PVC Classification based on QRS Pattern using QS Interval and R Wave Amplitude (QRS 패턴에 의한 QS 간격과 R파의 진폭을 이용한 조기심실수축 분류)

  • Cho, Ik-Sung;Kwon, Hyeog-Soong
    • Journal of the Korea Institute of Information and Communication Engineering
    • /
    • v.18 no.4
    • /
    • pp.825-832
    • /
    • 2014
  • Previous works for detecting arrhythmia have mostly used nonlinear method such as artificial neural network, fuzzy theory, support vector machine to increase classification accuracy. Most methods require accurate detection of P-QRS-T point, higher computational cost and larger processing time. Even if some methods have the advantage in low complexity, but they generally suffer form low sensitivity. Also, it is difficult to detect PVC accurately because of the various QRS pattern by person's individual difference. Therefore it is necessary to design an efficient algorithm that classifies PVC based on QRS pattern in realtime and decreases computational cost by extracting minimal feature. In this paper, we propose PVC classification based on QRS pattern using QS interval and R wave amplitude. For this purpose, we detected R wave, RR interval, QRS pattern from noise-free ECG signal through the preprocessing method. Also, we classified PVC in realtime through QS interval and R wave amplitude. The performance of R wave detection, PVC classification is evaluated by using 9 record of MIT-BIH arrhythmia database that included over 30 PVC. The achieved scores indicate the average of 99.02% in R wave detection and the rate of 93.72% in PVC classification.