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  • Yashmi Mahat, Joon Yau Leong, Paul H. Chung *
    Injuries to the bladder are infrequent and commonly result from blunt, penetrating, or iatrogenic trauma. Bladder injuries may be missed as they often present concomitantly with other abdominal
    and pelvic injuries; however, early detection and treatment are essential as morbidity and mortality may be significant. Gross hematuria, especially in the setting of pelvic fractures, may be indicative of a bladder injury which can be confirmed with cystography. Extraperitoneal injuries are commonly managed conservatively with catheter drainage while intraperitoneal ruptures traditionally required surgical exploration and closure. Presented is a contemporary review which encapsulates the etiology, presentation, assessment, and management of bladder injuries
    Keywords: Bladder, Trauma, Extraperitoneal, Intraperitoneal, Iatrogenic
  • Babak Nejati_Chien_Chin Lin_Vida Imani_Maria Browall_Chung_Ying Lin*_Anders Broström_Amir H Pakpour
    Background
    This study investigated the psychometric properties of the 9-Item Shared DecisionMaking Questionnaire (SDM-Q-9) and the 9-Item Shared Decision-Making Questionnaire–Physician version (SDM-Q-Doc) using comprehensive and thorough psychometric methods in an oncology setting.
    Methods
    Cancer survivors (n=1783; 928 [52.05%] males) and physicians (n=154; 121[78.58%] males) participated in this study. Each cancer survivor completed the SDM-Q-9. Physicians completed the SDM-Q-Doc for each of their cancer patient. Confirmatory factor analysis (CFA) and Rasch model were used to test the psychometric properties of SDM-Q-9 and SDM-Q-Doc.
    Results
    SDM-Q-9 and SDM-Q-Doc demonstrated unidimensional structure in CFA and Rasch model. In addition, the measurement invariance was supported for both SDM-Q-9 and SDM-QDoc across sex using the multigroup CFA. Rash analysis indicates no differential item functioning(DIF)across sex for all the SDM-Q-9 and SDM-Q-Doc items. SDM-Q-9 and SDM-Q-Doc were moderately correlated (r=0.41; P<0.001).
    Conclusion
    SDM-Q-9 and SDM-Q-Doc are valid instruments to assess shared decision making in the oncology setting.
    Keywords: Confirmatory factor analysis, Cancer, Rasch, Instrumentalstudy
  • Y. H. Liao, L. Y. Chung *
    By considering the supreme-utilities among fuzzy sets and the weights among participants simultaneously, we introduce the supreme-weighted value on fuzzy transferable-utility games. Further, we provide some equivalent relations to characterize the family of all solutions that admit a potential on weights. We also propose the dividend approach to provide alternative viewpoint for the potential approach. Based on these equivalent relations, several axiomatic results are also proposed to present the rationality for the supreme-weighted value.
    Keywords: Fuzzy transferable-utility games, the supreme-weighted value, potential, dividend, axiomatic result
  • J.C. Son, H.O. Jeong, E.K. Lee, S.G. No, D. Park, H.Y. Chung*
    Background
    Accumulating reports suggest that the biological effects of low- and high- dose ionizing radiation (LDIR and HDIR) are qualitatively different and might cause different effects in human skin.
    Materials and Methods
    To better understand the potential risks of LDIR, we analyzed three cDNA microarray datasets from the Gene Expression Omnibus database.
    Results
    A pathway analysis showed that genes in immune-associated pathways were upregulated while those in cancer-associated pathways were downregulated in skin exposed to LDIR as compared with non-irradiated control skin. Consistently, according to a comparative gene ontology analysis, “antigen presentation and processing” was the most different gene ontology between the LIDR and HDIR transcriptomes. To identify key molecules regulated by LDIR, we constructed a protein-protein interaction network analysis using topological metrics. One of the key molecules with a high network scores was E1A binding protein p300 (EP300), which is a potential target of a new therapeutic strategy to promote anti-tumor immunity.
    Conclusion
    Our results showed that LDIR exposure mainly induced the upregulation of immune-related genes including chemokines (CXCL1, CXCL2, and CXCL5) and interleukins (IL1B, IL11, IL6, IL15, and IL7). Additionally, LDIR induced the upregulation of antigen processing and presentation-related genes including CIITA, HLA-DQB1, and KIF26A, but these genes were downregulated in HDIR-exposed skin. Our protein network interaction results indicated that EP300 is downregulated by the immune response in skin after LDIR exposure.
    Keywords: LDIR, cDNA microarray, transcriptome, Bioinformatics, EP300.
  • Mohsen Saffari, Chung, Ying Lin, Harold G. Koenig, Keisha, Gaye N. O’Garo, Anders Brostr?m, Amir H. Pakpour*
    Background
    Dementia is prevalent among older adults and frequently causes dependence on family caregivers. Caregivers may experience a form of stigmatization called affiliate stigma that negatively affects their mental health. The current study sought to establish the psychometric properties of a tool to measure affiliate stigma among Iranian caregivers.
    Methods
    Overall, 541 caregivers of older people with dementia were included in this cross sectional study. Several measures were used to assess the psychometric properties of the Affiliate Stigma Scale (ASS) including the Zarit Burden Interview (ZBI), Hospital Anxiety and Depression Scale (HADS), Short Form 12 (SF-12), Rosenberg Self-Esteem Scale (RSES), and Multidimensional Scale of Perceived Social Support (MSPSS). Convergent and discriminate validity were examined.Exploratory and confirmatory factor analyses were utilized to assess the factor structure of the Ass and a Rasch model was used to evaluate the measurement functioning of the scale.
    Results
    Factor loadings ranged from 0.69 to 0.83 and test-retest reliability from 0.72 to 0.89.Item difficulty ranged widely from -0.66 to 0.89. No considerable differential item functioning (DIF) was found across gender. Confirmatory factor analysis confirmed the three cognitive,effective, and behavioral dimensions of the scale (comparative fit index [CFI]=0.931 to 0.995,root mean square error of approximation [RMSEA]=0.046 to 0.068). Internal consistency was acceptable (Cronbach’s α: 0.88 to 0.94). Significant and positive relationships were found between affiliate stigma and depression, anxiety, and care giving burden (β =0.35 to 0.46).
    Conclusion
    The ASS is a psychometrically valid measure for assessing affiliate stigma in Iranian caregivers of people with dementia. Application of this tool among other caregivers, language sand cultures deserves further study.
    Keywords: Stigma, Family caregivers, Dementia, Psychometrics
  • Y. C. Li, C. Y. Chung, F. M. Fang *
    Turbulent uniform flows past a two-dimensional square cylinder are investigated numerically. By varying the turbulence intensity and turbulence length scale of the approaching flow, the flow effect of the cylinder are compared to that in a laminar approaching-flow case. In addition, the variations of drag and lift coefficients with respect to the changes of turbulence intensity and turbulence length scale are analyzed on a systematic basis. In the large eddy simulations, the approaching-flow turbulence is generated by a spectral method according to Kármán spectrum. Two levels of turbulence intensities (5% and 10%) and three turbulence length scales (0.25, 0.50 and 1.0 times of the cylinder width) are selected in the study to examine the effect on the cylinder. Results show that the Strouhal number remains almost unchanged when the uniform approaching-flow changes from a laminar state to a turbulent one. The approaching-flow turbulence has noticeable effect in promoting the resulting drag and lift fluctuations. However, its effect on the mean drag appears negligible. In contrast, an increase of the approaching-flow turbulence length scale leads to mild increases of the mean and root-mean-square values of drag. On the other hand, the resulting lift fluctuation is insensitive to the change of the turbulence length scale.
    Keywords: Turbulent approaching flow, Square cylinder, Large eddy simulation
  • S.W. Kang, Dr. J.B. Chung *, J.W. Lee, M.J. Kim, Y.L. Kim, J.S. Kim, K.Y. Eom, I.A. Kim, Dr. T.S. Suh
    Background
    This study was conducted to assess the accuracy of dose calculation near the air-phantom interface of a heterogeneous phantom for Acuros XB (AXB) and Anisotropic Analytical Algorithm (AAA) algorithm of a 6-MV flattening-filter-free beam, compared with film measurements.
    Materials And Methods
    A phantom included air gap was specially manufactured for this study. In order to evaluate the dose near air gap-phantom interface, Eclipse treatment planning system equipped both AXB and AAA was used for the dose calculations. Measurements in this region were performed with radiochromic film. The central-axis dose (CAD) and off-axis dose (OAD) between calculations and measurements were analyzed for various field sizes and air gaps. The root-mean-square-error (RMSE) was used to evaluate the difference between the calculated and measured OAD. In order to quantify agreement between the calculated and measured dose distributions, the gamma analysis was performed with the 2%/2 mm and 3%/3 mm criteria.
    Results
    For all fields traveling through 1 and 3 cm air gap, the maximum difference in the calculated CAD was -5.3% for AXB and 214.8% for AAA, compared to the measured CAD. For the RMSE between the calculated and measured OAD, the calculated OAD using AXB showed interval in the RMSE (from 4.4 to 12.7) while using AAA indicated broad (from 7.7 to 101.0). In addition, the gamma passing rates showed that AXB was higher agreement than AAA.
    Conclusion
    This study demonstrated that AXB was more accurate in heterogeneous media near air-phantom interface than AAA when comparing the measured data.
    Keywords: Acuros XB, anisotropic analytical algorithm, heterogeneous media, FFF, interface
  • Y.L. Kim, Dr. T.S. Suh *, B.Y. Choe, B.O. Choi, J.B. Chung, J.W. Lee, Y.K. Bae, B.M. Park, J.Y. Jung, Y.J. Shin
    Background
    Dose calculation algorithms play a very important role in predicting the explicit dose distribution. We evaluated the percent depth dose (PDD), lateral depth dose profile, and surface dose volume histogram in inhomogeneous media using calculation algorithms and inhomogeneity correction methods.
    Materials And Methods
    The homogeneous and inhomogeneous virtual slab phantoms used in this study were manufactured in the radiation treatment planning system to represent the air, lung, and bone density with planned radiation treatment of 6 MV photons, a field size of 10 × 10 cm2, and a source-to-surface distance of 100 cm.
    Results
    The PDD of air density slab for the Acuros XB (AXB) algorithm was differed by an average of 20% in comparison with other algorithms. Rebuild up occurred in the region below the air density slab (10–10.6 cm) for the AXB algorithm. The lateral dose profiles for the air density slab showed relatively large differences (over 30%) in the field. There were large differences (20.0%–26.1%) at the second homogeneous–inhomogeneous junction (depth of 10 cm) in the field for all calculation methods. The surface dose volume histogram for the pencil beam algorithm showed a response that was approximately 4% lower than that for the AXB algorithm.
    Conclusion
    The dose calculation uncertainties were shown to change at the interface between different densities and in varied densities using the dose calculation methods. In particular, the AXB algorithm showed large differences in and out of the field in inhomogeneous media.
    Keywords: Inhomogeneous media, calculation algorithms, correction methods, PDD, dose profiles
  • Chung, Ying Lin, Santhosh Kumar, Amir H. Pakpour*
    Background
    The study aimed to further evaluate the psychometric properties of one recently developed oral health related quality of life (OHRQoL) instrument (PedsQL Oral Health Scale),including student self-report and parent-proxy report. Specifically, we tested the item validity,threshold order, local dependency, and differential item functioning (DIF) across gender and rater.
    Methods
    This is a cross-sectional study, and study population was recruited in Qazvin, Iran usingone-stage sampling with the unit of school. Students and their parents (1529 dyads) separately completed the Persian version of PedsQL Oral Health Scale. The psychometric properties were analyzed using Rasch rating scale model, including item validity, threshold order for response categories, and DIF across gender (boys vs. girls in student self-report) and rater (student self reportvs. parent-proxy report).
    Results
    All items had satisfactory in fit and outfit mean square error. One disordering category(the response of often) was found in parent-proxy report, while all categories were ordered in student self-report. All items were DIF-trivial across gender and rater.
    Conclusion
    PedsQL Oral Health Scale is a valid instrument to measure OHRQoL. However,our results indicated that the parent-proxy report was inferior to the student self-report, and healthcare providers should primarily use the student self-report.
    Keywords: Children, Construct validity, Differential item functioning, Oral health, Quality of life, Rasch
  • D.M. Chung, J.H. Kim, Dr. Jin Kyu Kim*
    Background
    Cell viability is an important factor in radiation therapy and thus is a method to quantify the effect of the therapy.
    Materials And Methods
    The viability of human hepatoma (HepG2) cells exposed to radiation was evaluated by both the MTT and Trypan blue assays. The cells were seeded on 96 well-plates at a density of 1 x 104 cells/well, incubated overnight, and irradiated with 1-100 Gy.
    Results
    The cell viability was decreased in a dose- and time- dependent manner when using the Trypan blue assay, but no significant changes in the response to dose could be detected using the MTT assay. It indicated that the MTT assay was not efficient at a cell density of 1 x 104 cells/well on 96 well-plates to determine cell viability. Subsequently, the relationship between cell viability and lower cell density (1 x 103, 3 x 103, and 5 x 103 cells/well) was investigated. A cell density of 1 x 103 was found to be the most effective when using the MTT assay. Results show that the cell density is most important when using the MTT assay in 96 well-plates to follow in radiation effects. Furthermore, the radiation-induced cell viability dependent on cell density was confirmed by using the traditional Clonogenic assay.
    Conclusion
    Our results suggest that the MTT and Trypan blue assays are rapid methods to detect radiation-induced cell viability of HepG2 cells in about 3 days as compared with 14 days of assay time in the Clonogenic assay. To obtain accurate cell viability measures using both rapid assays, an incubation time of at least 3 days is needed after irradiation.
    Keywords: Cell viability, clonogenic assay, HepG2 cell, MTT, radiation, trypan blue
  • Chung, Jung Fu, Cheng, Yan Kao, Yueh, Lun Lee, Chien, Wei Liao, Po, Ching Chen, Ting, Wu Chuang, Ying, Chin Wang, Chia, Mei Chou, Ying, Chie Huang, Toshio Naito, Chia, Kwung Fan
    Background
    Infection by Toxocara spp. is known to be significantly associated with partial epilepsy. It has become popular for people to raise dogs/cats as pets and consume roasted meat/viscera, and the status of Toxocara spp. infection, epi­lepsy awareness, and associated risk factors among the general population are cur­rently unknown in Taiwan.
    Methods
    A seroepidemiological investigation among 203 college students (CSs), consisting of 110 males and 93 females with an average age of 21.5 ± 1.2 years, was conducted in 2009 in Taipei City. A Western blot analysis based on excretory-secre­tory antigens derived from Toxocara canis larvae (TcESs) was applied to determine the positivity of serum immunoglobulin G antibodies. A self-administered question­naire was also given to obtain information about demographic characteris­tics, epilepsy awareness, and risk factors. A logistic regression model was applied for the statistical analysis using SPSS software.
    Results
    The overall seropositive rate of Toxocara spp. infection was 8.4% (17/203). As to epilepsy awareness, a non-significantly higher seroprevalence was found in CSs who claimed to "know" about epilepsy compared to those who did not know (P > 0.05).
    Conclusions
    It appears that appropriate educational programs are urgently needed to provide correct knowledge related to the prevention and control measures against Toxocara spp. infections to avoid potential threats by this parasite to the general population in Taiwan.
    Keywords: Toxocara spp., Western blot, Epilepsy awareness, College students, Tai¬wan
  • I. Y. Lee, H. S. Chung, S. J. Chang
    In this paper, we show that the conditional transform with respect to the Gaussian process involving the first variation can be expressed in terms of the conditional transform without the first variation. We then use this result to obtain various integration formulas involving the conditional ⋄ product and the first variation.
    Keywords: Brownian motion process, Gaussian process, simple formula, conditional transform with respect to Gaussian process, conditional ⋄, product, first variation
  • Z. Kazemi, N.B. Hashim, H. Aslani, Z. Liu, P.M. Craig, D.H. Chung, M. Ismail
    The Johor Strait is an estuarine system located on the coast of the state of Johor in Malaysia. The Western Part of Johor Strait is a shallow estuarine located between Causeway and Pulai River. A hydrodynamic model was calibrated based on the Environmental Fluid Dynamic Code (EFDC) from 4th to 17th of October, 2009. In this calibration, the EFDC hydrodynamic model was configured to simulate time series surface water elevation, velocity, and salinity. The model grid consisted of 2310 grid cells in the horizontal direction and four vertical layers. The model reasonably simulated the tidal range. The simulated velocity showed good agreement with observations data. The predicted salinity model Salinity compared the surface layer with observed data. Results of model showed that changes of salinity from surface to depth were uniform and this condition implied rapid vertical mixing of the water in the system. The calibration model can be used for water quality and sediment modeling and for studying water age modeling.
    Keywords: Hydrodynamic, EFDC, Salinity, Johor Strait, three, dimensional
  • Hsiu, Lin Huang, Ho, Ting Su, Chung, Hsiun Herbert Wu, Jyy, Jih Tsai, Wu *
    Background
    Mycobacterium tuberculosis is a vicious microbe co-existing with the infected host. This pathogen exploited opportunities to spread during periods of urbanization and social upheaval, and got retreated with improved hygiene..
    Objectives
    This investigation was designed to clone and characterize M. tuberculosis mutT gene, a homologue of a DNA repair protein in Escherichia coli. The aim was to depict the possible role of this homologue in the virulent microbe..
    Materials And Methods
    A DNA fragment of the mutT gene was amplified with PCR from the genomic DNA of strain H37Rv M. tuberculosis. The expression vector was transformed into E. coli strains BL21 (DE3) and MK602 (DE3) (mutT-). The protein activity assay was performed by biochemical methods..
    Results
    M. tuberculosis MutT shares 23% identity with the E. coli MutT protein. The mutT gene DNA fragment was subcloned into the expression vector pET28a(+) and the recombinant plasmid was overexpressed in E. coli. Purified and refolded M. tuberculosis MutT possesses a dGTPase activity, which is one of the most well-known preference nucleotidase activities of MutT in E. coli. This study also showed that the dGTPase activity of M. tuberculosis MutT was enhanced by magnesium and inhibited by Ni2+ or EDTA. Endogenous MutT protein in M. tuberculosis lysate displayed a smear pattern in the Western blot, suggesting instability of this protein in the bacteria similar to the important proteins, such as P53 protein, tightly regulated by protein degradation..
    Conclusions
    The cloned M. tuberculosis mutT gene and MutT protein were characterized. M. tuberculosis MutT has a dGTPase activity, which is one of the most well-known preference nucleotidase activities of MutT in E. coli. These findings provide further understanding about the vicious bacterium..
    Keywords: Mycobacterium tuberculosis, Protein Array Analysis, Escherichia coli
  • مریم اتحادی ابری، باریس مجنونیان، وودام چونگ، احسان عبدی
    حمل و نقل ثانویه از جنگل به یارد کارخانه، از مولفه های اساسی هزینه در تولید چوب در مناطق مختلف جهان است. کوچک ترین افزایش بازدهی، به طور معنی داری هزینه ها را کاهش می دهد. با بهینه سازی و انتخاب مسیرهای مناسب در عملیات حمل چوب از مراکز تولید، یعنی طرح های جنگلداری به کارخانه های صنایع چوب و کاغذ، می توان ضمن کاهش هزینه ها، بازده تولید و ارزش افزوده فراورده ها را نیز افزایش داد. هدف از این تحقیق، یافتن مسیرهای مناسب حمل چوب توسط مجریان طرح های جنگلداری به سمت کارخانه ها و واحدهای صنایع چوب و کاغذ و حداقل سازی هزینه های حمل و نقل ثانویه است. به منظور تعیین هزینه های حمل و نقل ثانویه، در مجموع 46 طرح جنگلداری واقع در چهار اداره کل گلستان، ساری، نوشهر و گیلان و 38 کارخانه صنایع چوب و کاغذ با استفاده از نرم افزار NETWORK 2000 بررسی شد. نتایج نشان داد که با فرض اینکه هر طرح جنگلداری بتواند به هر کدام از صنایع چوب و کاغذ، چوب حمل کند، در مجموع 1682 مسیر برای حمل و نقل چوب وجود خواهد داشت که کمترین هزینه، 1600ریال بر متر مکعب و بیشترین هزینه، 633600 ریال بر مترمکعب است. با استفاده از نرم افزار NETWORK 2000، 353 مسیر از بین 1682 مسیر، به عنوان مسیرهای بهینه (کمترین هزینه حمل و نقل) معرفی شد. نرم افزار برای هر طرح جنگلداری هشت مسیر تعیین کرده است که هر مسیر، به یکی از کارخانه های موجود در هشت صنعت فعال در صنایع چوب و کاغذ ختم می شود یعنی به کمک نرم افزار هر طرح جنگلداری می تواند یکی از کارخانه های موجود در هشت صنعت فراورده های چوبی را انتخاب کند. در نهایت با داشتن هزینه های کل برای هر یک از این هشت مسیر، تنها یک مسیر به عنوان بهترین مسیر انتخاب می شود.
    کلید واژگان: بهینه سازی, حمل و نقل ثانویه, طرح جنگلداری, کارخانه های چوب و کاغذ, نرم افزار NETWORK 2000
    M. Etehadi Abari, B. Majnounian, W. Chung, E. Abdi
    Forest operations consist of all technical and administrative processes to develop technical structures and facilities. Transportation, is the stage where there is greatest potential for savings, is the subject of this research. The transportation of logs is performed in two stages; transport from forest to road sides and transport from road sides to terminals or customers (such as sawmills and pulp mills). The transportation of logs is very costly with a high percentage, in the range of 15 to 20%, of the cost of timber. From the public’s perspective, logging trucks are perhaps the most visible sign of forest industries. The problem of planning the transportation from forest road sides to customers is complex. The goal of the transportation planning is to construct schedules for the trucks, such that all customer demands are satisfied on time with minimum trucking costs. From the forest industry’s perspective, transporting logs from the forest to the mill is becoming the largest single component of wood supply costs for many suppliers around the world. Since transportation costs make up a large proportion of the overall costs, even small increases in efficiency can significantly reduce costs. There is, therefore, considerable interest by forest industries worldwide in new work procedures, decision support systems that can lead to reductions in overall transport costs and numbers of trucks on the road. This research objective is to develop transportation plan to minimize haul costs and determine the cost of secondary transportation from forest management to mills. This study has been carried out in forest management in Hyrcanian forest and mill that consume wood products in north of Iran. In order to determine the total cost of secondary transportation at total 46 forest managements and 38 mills are considered and are investigated by using NETWORK2000. The results show that if all forest managements can send their products (logs, pulpwood, fuelwood, and swan-lumber) to all mills there are 1748 routes for wood transportation that among them minimum cost is 1600 Rial/m3 and maximum cost is 633600 Rial/m3. With use of NETWORK 2000, in total 368 routes chosen among 1748 routes as optimal cost routes. In this case maximum cost is 380000 Rial/m3 and in this case 253600 Rial/m3 is saved and economized in transport costs.
    Keywords: Forest management plan, NETWORK 2000, Optimization, Secondary forest transportation, Wood industry
  • محمدحسین زرین کوب، سون لیگ چانگ، سیدسعید محمدی، محمد مهدی خطیب
    توده گرانیتوئیدی بی بی مریم با وسعت حدود 5 کیلومترمربع به درون نوار افیولیت ملانژ خاور ایران، در پهنه جوش خورده سیستان نفوذ کرده است. آثار حرارتی این توده بر روی سنگهای میزبان نشان می دهد که این فعالیت بعد از جای گیری افیولیت ملانژ رخ داده است. این توده نفوذی که دارای روند کلی شمال باختری - جنوب خاوری است عمدتا از تونالیت -کوارتزدیوریت تشکیل شده ولی در بخش شمال باختری آن یک واحد فرعی گرانودیوریتی به صورت دایک بروز کرده است. بافت غالب در توده تونالیتی _ کوارتزدیوریتی، دانه ای و در بخش گرانودیوریتی، دانه ای، میرمکیتی و گرافیکی است. کوارتز، پلاژیوکلاز (الیگوکلاز _ آندزین) و بیوتیت به عنوان کانی های اصلی و آمفیبول (هورنبلند)، آپاتیت، زیرکان و کانی کدر از اجزای فرعی واحد اصلی این توده می باشند. کوارتز، پلاژیوکلازسدیک و آلکالی فلدسپار کانی های اصلی و گارنت، آپاتیت و کانی های کدر، کانی های فرعی واحد گرانودیوریتی را می سازند. توده گرانیتوئیدی بی بی مریم در محدوده کالک آلکالن، متا آلومین تا اندکی پر آلومین و از نوع کمان ماگمایی قرار می گیرد. بالا بودن نسبت LREE/HREE، مقدار نسبت Sr/Y (میانگین 7/38)، و مقدار SiO2(میانگین48/69) به همراه فقدان آنومالی منفیEu نشان میدهند که این سنگها شباهت زیادی به آداکیت های غنی از سیلیس دارند. افزایش نسبت Sr/Y ناشی از ذوب عمیق و در محدوده ناپایدار شدن پلاژیوکلاز و پایداری گارنت تعبیر می شود. این ماگما می تواند از یک منبع اکلوژیتی یا گارنت آمفیبولیتی، حاصل از دگرگونی ورقه اقیانوسی فرورانده شده خاور ایران، سرچشمه گرفته باشد. سن سنجی به روش زیرکان اورانیم - سرب بر روی دانه های زیرکان جدا شده از فاز اصلی (تونالیت _ کوارتزدیوریت) نشان می دهد که این ماگماتیسم در 6/. ± 5/71 میلیون سال (ماستریشتین) رخ داده است. با توجه نتیجه سن سنجی می توان سن جای گیری افیولیت ملانژ میزبان را قبل از ماستریشتین دانست.
    کلید واژگان: گرانیتوئید, بی بی مریم, سن سنجی, زیرکان, اورانیم, سرب, خاور ایران
    M.H. Zarrinkoub, S.L. Chung, S.S. Mohammadi, M.H. Khatib
    Bibi Maryam granitoid body with about 5 Km2 has intruded into ophiolite mélange complex in sistan suture zone, in east of Iran. Thermal effects of this body on the host rocks show that this activity occurred after emplacement of ophiolite mélange. This intrusive body with general northwest – southeast trend is mainly tonalite-quartz diorite but there is a minor unit as dykes of granodiorite in the northwest side. Main texture in tonalite - quartz diorite is granular and in granodiorite part, granular, myrmekitic and graphic are popular. Quartz, plagioclase (oligoclase-andesin) and biotite are the main minerals and the minors are amphibol, apatite, zircon and opaque in the main body. Quartz, sodium plagioclase and alkali feldspar are the main minerals and the minors are garnet, apatite and opaque minerals in granodiorite unit. Bibi Maryam granitoid is magmatic arc type and has plotted in calc-alkaline, metaluminous to peraluminous field.High ratio of LREE / HREE, Sr/Y (average is 38.7), and SiO2 amount(average is 69.48) with absent of Eu negative anomaly show these rocks are very similar to high SiO2 adakites. High ratio of Sr/Y can be interpreted of high depth melting in plagioclase unstability and garnet stability field. The source of this magma can be an eclogite or garnet amphibolites which derived of subducted metamorphosed oceanic plate in east of Iran. Dating on zircon grains in the main body (tonalite-quartzdiorite) with zircon uranium – lead shows this magmatic event has occurred at 71.5 ± 0.6 Ma (maestrichtian). Based on this dating, the emplacement of host ophiolite mélange should occurred before maestrichtian.
  • محمدحسین زرین کوب، سون لین چانگ، سید سعید محمدی، محمد مهدی خطیب، غلامرضا فتوحی راد، ابراهیم غلامی، فاطمه عباسلو
    توده گرانیتوییدی مورد مطالعه در یک مجموعه دگرگونی منسوب به پروتروزوییک در جنوب روستای زول، شمال استان خراسان جنوبی، در خاور ایران، واقع شده است. سنگ های تشکیل دهنده این مجموعه شامل گرانیت، گنیس، میگماتیت، میکاشیست، گارنت شیست و به مقدار کمتر مرمر و کوارتزیت است. براساس مطالعات کانی شناسی، داده های مودال و ژئوشیمیایی، گرانیتویید زول از نوع گرانیت و گرانودیوریت است. این سنگ ها دارای بافت دانه ای، گرافیک و به ندرت پورفیروییدی هستند. این گرانیتویید دارای ترکیب کلسیمی قلیایی و پرآلومین است. الگوی عناصر جزئی بهنجار شده این سنگ ها نسبت به میانگین پوسته، حاکی از غنی شدگی آنها از عناصر K، Th،U است. این ویژگی ها با حضور بی هنجاری منفی یوروپیم در این سنگ ها می-تواند ذوب رسوبات پوسته ای در یک محیط زمین ساختی برخوردی تشکیل گرانیتوئید نوع S را تایید کند. سن سنجی ایزوتوپی به روش زیرکن اورانیم _ سرب، حاکی از حضور دو نسل زیرکن ارثی و ماگمایی در این گرانیتویید است. سن زیرکن های ارثی 2 ± 4/168 میلیون سال و سن تبلور فاز گرانیتی 5/1 ± 1/110 میلیون سال (اواخر کرتاسه پیشین) به دست آمد.
    کلید واژگان: سن سنجی, زمین ساخت برخوردی, خاور ایران, گرانیتویید, زیرکن اورانیم, سرب
    M.H. Zarrinkoub, S.L. Chung, S.S. Mohammadi, M.M. Khatib, G.R. Fotoohi, Rad, E. Gholami, F. Abbaslu
    The present study is concerned with granitoid body crops out in a metamorphic complex occurring around Zul village of South Khorasan Province, eastern Iran. The complex is composed of migmatite, gneiss, mica schist, garnet schist, some marble and quartzite. Based on mineralogy, modal and geochemical data, Zul granitoid includes granite and granodiorite. These rocks are granular, graphic and porphyroid in texture. Major minerals are alkali feldspar, quartz, biotite and muscovite. Tourmaline, sphene, apatite, zircon and garnet are the minor mineral components. The granitoid is calc-alkaline and peraluminous in composition. Trace element data were normalized to average crust, showing enrichment in K, U and Th. These characteristics and negative anomaly for Eu can indicate melting of crustal sediments (S-type granitoid) in a collision-related tectonic environment.Isotope age dating on zircon uranium – lead indicates that, there are two generations of heritage and magmatic zircon in granitoid phase. Heritage zircon show 168.4 ± 2 Ma and magmatic zircon has 110.1 ± 1.5 Ma (late Early Cretaceous) age.
    Keywords: Age dating_collision_related tectonic_Eastern Iran_granitoid_zircon uranium – lead
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