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1Obesity, metabolic syndrome and diabetic retinopathy: Beyond hyperglycemia显示文摘Diabetic retinopathy(DR) is the most feared ocular manifestation of diabetes. DR is characterized by progressive retinal damage that may eventually result in blindness. Clinically, this blindness is caused by progressive damage to the retinal microvasculature, which leads to ischemia, retinal swelling, and neovascularization. Retinopathy is associated with both type 1 and type 2 diabetes, with DR being the leading cause of new onset blindness in United States adults. Despite this strong association with diabetes, it must be noted that the development of retinopathy lesions is multifactorial and may occur in individuals without an established history of diabetes. Metabolic syndrome is a multifactorial condition of central obesity, hypertriglyceridemia, dyslipidemia, hypertension, fasting hyperglycemia, and insulin resistance. Although several studies examined the individual components observed in the metabolic syndrome in relation to the development of DR, there is conflicting data as to the association of the metabolic syndrome with the development of retinopathy lesions in nondiabetic subjects. This review will summarize the current literature on the evidence of the metabolic syndrome on retinopathy in subjects with and without an established history of diabetes. This review will also discuss some of the mechanisms through which metabolic syndrome can contribute to the development of retinopathy.Osinakachukwu Mbata Nada Fawzy Abo El-Magd Azza Bahram El-Remessy 2017World Journal of Diabetes2017,8,7:16
2Potential role of N-carbamoyl glutamate in biosynthesis of arginine and its significance in production of ruminant animals显示文摘Arginine(ARG) exerts many beneficial effects on animal body and enhanced angiogenesis, lactogenesis, which finally leads to the improvement in nitrogen(N) metabolism, reproduction, lactation, immunity and growth. Unfortunately, unprotected ARG will be degraded in the rumen and its price is high, thus feeding rumen-protected ARG seems to be uneconomical. Alternatively, N-carbamoyl glutamate(NCG) is structural analogue of N-acetyl glutamate, cofactor of cabamoyl phosphate synthetase 1, is lower in rumen degradation compared to ARG. Additionally, rumen epithelial and duodenal cells have potentially utilized the NCG for ureagenesis. Supplementation of NCG to high yielding dairy cows increased plasma concentration of ARG and nitric oxide, decreased the plasma ammonia N and improved lactation performance and N utilization. Supplementation of NCG enhanced pregnancy rates in rats, improved litter size and fetal survival rate, thereby improved the reproductive performance of sows. Oral NCG supplementation increases plasma ARG and somatotropin levels, and increased growth rate and muscle protein synthesis in nursing piglets. The NCG is potential a relatively cheaper source of feed additive to offer vital compensation over oral administration of ARG, resulting in improved ruminant animal health and production. In this article, we reviewed the mechanism of ARG biosynthesis by NCG and their significance in growth, reproduction, milk production and N utilization in ruminant animals.Bahram Chacher Hongyun Liu Diming Wang Jianxin Liu 2013Journal of Animal Science and Biotechnology2013,4,4:15
3橡胶和SBS对排水沥青混合料性能影响的试验研究显示文摘排水沥青路面(PA)具有良好的排水和降噪性能,但相对于密级配沥青混合料,其抗车辙能力、抗疲劳与抗水损害等性能较差。为评价橡胶颗粒(CR)对排水沥青路面性能的影响,以普通排水沥青混合料与5%SBS改性排水沥青混合料为对照组,研究了CR掺量为10%、15%、20%橡胶改性排水沥青混合料的抗车辙、抗析漏、抗滑与水稳定性等性能。结果表明:CR和SBS既降低了排水沥青路面的渗透性,也显著提高了抗车辙能力。同时CR还可以提高混合料的初期回弹模量、抗滑性和抗水损害能力,但CR掺量过大会对路面性能产生不利影响。刘梦梅 韩森 任万艳 Bahram Shirini Reza Imaninasab 2018中外公路2018,38,3:13
4Microbiologic spectrum of acute and chronic dacryocystitis显示文摘AIM:To report the microbiological spectrum of acute and chronic dacrocystitis.METHODS:Retrospective study on 100 patients who presented to the ophthalmic plastic clinic of a tertiary eye care center from May 2011 and April 2013 with acute and chronic dacryocystitis was reviewed for demographic and microbiological profile. The culture results and organisms isolated were recorded.RESULTS:Sixty patients had acute onset and the remaining 40 patients had chronic onset dacryocystitis.The female to male ratio was 1.78. The mean age of patients was 44 y. Gram-positive organisms were the most commonly isolated accounting for 54%, and the commonest species isolated was S. aureus in 26%.Percentage of gram positive cultures was higher in chronic dacryocystitis than acute ones(82% vs 48% of positive cultures; P =0.003). Also in culture positive acute dacryocystitis, gram negative species were found in 52%of eyes but only in 18% of chronic dacryocystitis.CONCLUSION:Gram negative bacteria, culture negative samples, unusual and more virulent organisms are more common in acute dacryocystitis than chronic ones. The results of this study have significant bearing on the treatment of patients with dacrocystitis.Bahram Eshraghi Parisa Abdi Mohammadreza Akbari Masoud Aghsaei Fard 2014International Journal of Ophthalmology(English edition)2014,7,5:11
5Effect of Silicon on Growth and Development of Strawberry under Water Deficit Conditions显示文摘Water stress is a major factor that limits agricultural crop production. Silicon(Si) is generally considered as a beneficial element for the growth of higher plants, especially for those grown under stressful environment. This study was conducted to examine the effects of Si on growth and development of strawberry(Fragaria × ananassa ‘Camarosa') under water stress conditions. A factorial experiment, in a completely randomized design, was used to investigate the effects of three irrigation levels and four Si treatments consisting of 0, 5, 10, and 15 mmol·L^(-1) potassium silicate(K_2 SiO_3). The results showed that an increase in the levels of water stress caused a decrease in most of the quantitative characteristics such as specific leaf area, chlorophyll fluorescence, net photosynthesis rate, and stomata conductance; addition of Si significantly increased most of the mentioned factors; water stress increased electrolyte leakage, proline, and water use efficiency(WUE); Si treatment significantly decreased transpiration rate and improved chlorophyll content and WUE. Water stress stimulated mineral nutrient absorption whereas Si application decreased it under water stress. In conclusion, it was found that in most of the investigated factors, 10 mmol·L^(-1) potassium silicate had the best effect on growth and development of strawberry. Besides, Si application had beneficial effects on strawberry plants and the addition of it could alleviate water stress.DEHGHANIPOODEH Safoora GHOBADI Cyrus BANINASAB Bahram GHEYSARI Mahdi SHIRANIBIDABADI Siamak 2018Horticultural Plant Journal2018,4,6:9
6Watershed classification by remote sensing indices: A fuzzy c-means clustering approach显示文摘Determining the relatively similar hydrological properties of the watersheds is very crucial in order to readily classify them for management practices such as flood and soil erosion control. This study aimed to identify homogeneous hydrological watersheds using remote sensing data in western Iran. To achieve this goal, remote sensing indices including SAVI, LAI, NDMI, NDVI and snow cover, were extracted from MODIS data over the period 2000 to 2015. Then, a fuzzy method was used to clustering the watersheds based on the extracted indices. A fuzzy c-mean(FCM) algorithm enabled to classify 38 watersheds in three homogeneous groups.The optimal number of clusters was determined through evaluation of partition coefficient, partition entropy function and trial and error. The results indicated three homogeneous regions identified by the fuzzy c-mean clustering and remote sensing product which are consistent with the variations of topography and climate of the study area. Inherently,the grouped watersheds have similar hydrological properties and are likely to need similar management considerations and measures.Bahram CHOUBIN Karim SOLAIMANI Mahmoud HABIBNEJAD ROSHAN Arash MALEKIAN 2017Journal of Mountain Science2017,14,10:9
7Influence of the roughness and shape of quartz particles on their flotation kinetics显示文摘Surface roughness and shape play an important role on the behavior of particles in various processes such as flotation. In this re-search, the influence of different grinding methods on the surface roughness and shape characteristics of quartz particles as well as the effect of these parameters on the flotation of the particles was investigated. The surface roughness of the particles was determined by measuring their specific surface area via the gas adsorption method. The shape characteristics of the particles were measured and calculated by images obtained by scanning electron microscopy via an image analysis system. The flotation kinetics was determined using a laboratory flotation cell. The results showed that the particles of rod mill products have higher roughness and elongation ratio and lower roundness than the parti-cles of ball mill products. The flotation kinetics constant of the particles increased with their surface roughness increasing. Particles with higher elongation and lower roundness indicated higher floatability. In addition, the influence of the surface roughness on the flotation kinet-ics was greater than that of shape parameters.Mehdi Rahimi Fahimeh Dehghani Bahram Rezai Mohammad Reza Aslani 2012International Journal of Minerals,Metallurgy and Materials2012,19,4:8
8Strategies for reducing speckle noise in digital holography显示文摘Digital holography(DH)has emerged as one of the most effective coherent imaging technologies.The technological developments of digital sensors and optical elements have made DH the primary approach in several research fields,from quantitative phase imaging to optical metrology and 3D display technologies,to name a few.Like many other digital imaging techniques,DH must cope with the issue of speckle artifacts,due to the coherent nature of the required light sources.Despite the complexity of the recently proposed de-speckling methods,many have not yet attained the required level of effectiveness.That is,a universal denoising strategy for completely suppressing holographic noise has not yet been established.Thus the removal of speckle noise from holographic images represents a bottleneck for the entire optics and photonics scientific community.This review article provides a broad discussion about the noise issue in DH,with the aim of covering the best-performing noise reduction approaches that have been proposed so far.Quantitative comparisons among these approaches will be presented.Vittorio Bianco Pasquale Memmolo Marco Leo Silvio Montresor Cosimo Distante Melania Paturzo Pascal Picart Bahram Javidi Pietro Ferraro 2018Light(Science & Applications)2018,7,1:8
9Persistent alanine aminotransferase elevation among the general Iranian population: Prevalence and causes显示文摘AIM: To determine the prevalence and causes of persistently elevated alanine aminotransferase (ALT) levels among the general population in northern Iran. METHODS: A total of 2292 (1376 female, aged 18-75 year), were selected by systematic clustered random sampling from the cities and villages of Gonbad and Kalaleh in Golestan Province and invited to participate in the study. A comprehensive history regarding alcohol drinking and medication was taken. Body mass index (BMI), viral markers and ALT levels were measured. If ALT level was ≥ 40 U/L, it was rechecked twice within 6 mo. Those with ≥ 2 times elevation of ALT were considered as having persistently elevated ALT level. Non-alcoholic fatty liver disease (NAFLD) was diagnosed based on evidence of fatty liver upon sonography and excluding other etiology. RESULTS: A total of 2049 (1351 female) patients participated in the study, 162 (7.9%) had elevated ALT level at the first measurement. Persistently elevated ALT level was detected in 64 (3.1%) participants, with51 (79.6%) with no obvious etiology, six (9.3%) with Hepatitis B, four (6.2%) with Hepatitis C virus (HCV) infection and three (4.6%) with alcoholic hepatitis. The prevalence of NAFLD and alcoholic hepatitis was 2.04% (42 patients) and 0.1% (three), respectively. There was correlation between NAFLD and male gender, overweight, diabetes and living in an urban area [odds ratio = 3.03 (95% CI: 1.6-5.72), 4.21 (95% CI: 1.83-9.68), 2.86 (95% CI: 1.05-7.79) and 2.04 (95% CI: 1.00-4.16) respectively]. CONCLUSION: NAFLD is the most common cause of persistently elevated serum ALT level among the general population of Iran.Raika Jamali Mahmoodreza Khonsari Shahin Merat Masoud Khoshnia Elham Jafari Alireza Bahram Kalhori Hassan Abolghasemi Sedighe Amini Mahtab Maghsoudlu Mohammad Reza Deyhim Houri Rezvan Akram Pourshams 2008World Journal of Gastroenterology2008,14,18:7
10Power systems wide-area voltage stability assessment considering dissimilar load variations and credible contingencies显示文摘This paper reveals that the existing techniques have some deficiencies in the proper estimation of voltage stability margin(VSM) when applied to a power system with different load change scenarios.The problem gets worse when credible contingencies occur.This paper proposes a real-time wide-area approach to estimate VSM of power systems with different possible load change scenarios under normal and contingency operating conditions.The new method is based on an artificial neural network(ANN) whose inputs are bus voltage phasors captured by phasor measurement units(PMUs) and rates of change of active power loads.A new input feature is also accommodated to overcome the inability of trained ANN in prediction of VSM under N-1 and N-2 contingencies.With a new algorithm, the number of contingencies is reduced for the effective training of ANN.Robustness of the proposed technique is assured through adding a random noise to input variables.To deal with systems with a limited number of PMUs, a search algorithm is accomplished to identify the optimal placement of PMUs.The proposed method is examined on the IEEE 6-bus and the New England 39-bus test system.Results show that the VSM could be predicted with less than 1% error.Bahram SHAKERIGHADI Farrokh AMINIFAR Saeed AFSHARNIA 2019Journal of Modern Power Systems and Clean Energy2019,7,1:7
11High-level classification of the Fungi and a tool for evolutionary ecological analyses显示文摘High-throughput sequencing studies generate vast amounts of taxonomic data.Evolutionary ecological hypotheses of the recovered taxa and Species Hypotheses are difficult to test due to problems with alignments and the lack of a phylogenetic backbone.We propose an updated phylum-and class-level fungal classification accounting for monophyly and divergence time so that the main taxonomic ranks are more informative.Based on phylogenies and divergence time estimates,we adopt phylum rank to Aphelidiomycota,Basidiobolomycota,Calcarisporiellomycota,Glomeromycota,Entomophthoromycota,Entorrhizomycota,Kickxellomycota,Monoblepharomycota,Mortierellomycota and Olpidiomycota.We accept nine subkingdoms to accommodate these 18 phyla.We consider the kingdom Nucleariae(phyla Nuclearida and Fonticulida)as a sister group to the Fungi.We also introduce a perl script and a newick-formatted classification backbone for assigning Species Hypotheses into a hierarchical taxonomic framework,using this or any other classification system.We provide an example of testing evolutionary ecological hypotheses based on a global soil fungal data set.Leho Tedersoo Santiago Sanchez-Ramırez Urmas Koljalg Mohammad Bahram Markus Doring Dmitry Schigel Tom May Martin Ryberg Kessy Abarenkov 2018Fungal Diversity2018,,3:7
12ANALYTICAL ANALYSIS OF MEMS CAPACITIVE PRESSURE SENSOR WITH CIRCULAR DIAPHRAGM UNDER DYNAMIC LOAD USING DIFFERENTIAL TRANSFORMATION METHOD(DTM)显示文摘In this paper, first a circular diaphragm is modeled using the classical plate theory.An analytical solution based on differential transformation method(DTM) and Runge-Kutta method is employed for solving the governing differential equation for the first time. Then the influences of various parameters on central deflection of the diaphragm, stress distribution and capacitance of pressure sensor with a time-dependent pressure are examined. Several case studies are compared with simulations to confirm the proposed method. The analytical results compared with ABAQUS simulation show excellent agreement with the simulation results. This method is very promising for time saving in calculating micro-device characteristics.Marzieh Molla-Alipour Bahram Azizollah Ganji 2015Acta Mechanica Solida Sinica2015,28,4:6
13Bonded-particle model calibration using response surface methodology显示文摘Sajjad Chehreghani Mohammad Noaparast Bahram Rezai Sied Ziaedin Shafaei 2017Particuology2017,15,3:6
14Estimation of froth flotation recovery and collision probability based on operational parameters using an artificial neural network显示文摘An artificial neural network and regression procedures were used to predict the recovery and collision probability of quartz flotation concentrate in different operational conditions. Flotation parameters, such as dimensionless numbers (Froude, Reynolds, and Weber), particle size, air flow rate, bubble diameter, and bubble rise velocity, were used as inputs to both methods. The linear regression method shows that the relationships between flotation parameters and the recovery and collision probability of flotation can achieve correlation coefficients (R2) of 0.54 and 0.87, respectively. A feed-forward artificial neural network with 3-3-3-2 arrangement is able to simultaneously estimate the recovery and collision probability as the outputs. In testing stages, the quite satisfactory correlation coefficient of 0.98 was achieved for both outputs. It shows that the proposed neural network models can be used to determine the most advantageous operational conditions for the expected recovery and collision probability in the froth flotation process.Saeed Chehreh Chelgani Behzad Shahbazi Bahram Rezai 2010International Journal of Minerals,Metallurgy and Materials2010,17,5:5
15Higher order aberration comparison between two aspherical intraocular lenses: MC6125AS and Akreos advanced optics显示文摘AIM: To compare higher order aberrations in two aspherical intraocular lenses(IOLs): Akreos advanced optics(AO) and Dr. Schmidt Microcrystalline 6125 aspheric anterior surface(MC6125AS) with each other. METHODS: Forty eyes of 39 patients underwent phacoemulsification and Akreos AO and MC6125 AS were implanted in their eyes in a random manner. Three months post-operatively, higher order aberrations including spherical aberration, coma aberration, and total aberrations were measured and compared.RESULTS: The total aberration was 0.24±0.17 in eyes with Dr. Schmidt and 0.20 ±0.01 in eyes with Akreos AO(P =0.361). The mean of coma aberration was 0.17 ±0.21 and 0.09 ±0.86 in Dr. Schmidt and Akreos lenses,respectively(P =0.825). Total spherical aberration was almost the same in both groups(mean: 0.05, P =0.933).Best corrected visual acuity in Akreos AO(0.10±0.68) and Dr. Schmidt(0.09±0.67) did not differ significantly(P =0.700). CONCLUSION: There is no statistically significant difference in the higher order aberrations between these two aspherical lenses.Mohammad Taher Rajabi Sara Korouji Mahgol Farjadnia Mohammad Naderan Mohammad Bagher Rajabi Bahram Khosravi Seyed Mehdi Tabatabaie 2015International Journal of Ophthalmology(English edition)2015,8,3:5
16Eu^3+掺杂的ZnO微晶玻璃的制备及其发光性能显示文摘通过熔融热处理方法得到了Eu3+掺杂氧化锌微晶玻璃。利用XRD、透射电子显微镜研究了热处理后微晶玻璃的微结构。利用发射光谱研究了其发光性能。结果表明,样品在750℃热处理2h后,在玻璃网络中形成了尺寸约10nm的ZnO纳米晶。结构研究显示结晶后Eu3+进入了ZnO晶格之中。发射光谱显示其发光性能随着ZnO含量的增加以及热处理时间的增加而显著增强。黄晟辰 赵高凌 Bahram Ghaemi 汪建勋 韩高荣 2012材料科学与工程学报2012,30,1:5
17Intraocular complications of IFN-α and ribavirin therapy in patients with chronic viral hepatitis C显示文摘We report a panel of severe inflammatory and vascular intraocular disorders occurring during interferon-alpha (IFN-α) treatment in eight hepatitis C virus (HCV)-infected patients. These events include three cases of Vogt-Koyanagi-Harada like (VKH) disease (an association of panuveitis, retinal detachment, ear and meningeal detachment and skin and hair changes), two cases of central retinal vein occlusion, one case of central retinal artery occlusion, one case of severe hypertensive retinopathy and one case of bilateral ischemic optic neuropathy with severe visual impairment. Rare as they are, such severe ophthalmological complications require a close follow-up of HCV-infected patients under IFN-α treatment with ophthalmological monitoring if any ocular manifestation occurs.Damien Sène Valérie Touitou Bahram Bodaghi David Saadoun Gabriel Perlemuter Nathalie Cassoux Jean-Charles Piette Phuc Le Hoang Patrice Cacoub 2007World Journal of Gastroenterology2007,13,22:5
18先天性上睑下垂患者100例弱视致病原因的探讨(英文)显示文摘目的:评估先天性上睑下垂患者的弱视发病情况。方法:在本横断面研究中,包括1岁以上的先天性上睑下垂患者100例(114眼)。最佳矫正视力小于10/10或两眼之间至少相差2/10者定义为弱视。年幼患者不能进行斯内伦视力表检测者,观察其注视情况。不同弱视患者的类型:1)屈光参差性弱视:散光性屈光参差≥1.00D;远视性球镜屈光参差≥1.00D,近视性球镜屈光参差≥-3.00D(睫状肌麻痹);2)斜视性弱视,3)形觉剥夺性弱视(SDA)。观察弱视的总发病率及类型,并对单侧和双侧上睑下垂患者进行比较。结果:弱视的发生率在上睑下垂患者为39/114(34.2%),其具体原因:屈光参差性弱视占29.8%,SDA占10.5%,斜视性弱视4.3%,严重的上睑下垂患者弱视发病率更高,视轴遮盖者(OA)占76%,而视轴未遮盖者只占22%。在视轴遮盖的单侧眼睑下垂患者,散光屈光参差性弱视发生率更高,在双侧眼睑下垂至少1眼视轴遮盖者,球镜屈光参差性弱视发生率更高。无论单侧和双侧上睑下垂,如果有视轴遮盖,则SDA比较多见。结论:由于屈光参差性弱视比SDA发生率更高,关注导致的弱视所有原因对于预防儿童上睑下垂所致的弱视极其重要。Abolfazl Kasaee Alireza Yazdani-Abyaneh Syed Ziaeddin Tabatabaie Alireza K.Jafari Ahmad Ameri Bahram Eshraghi Vafa Samarai Meysam Mireshghi Mohammad Taher Rajabi 2011国际眼科杂志2011,11,3:4
19Numerical simulation of high voltage electric pulse comminution of phosphate ore显示文摘Numerical simulation of the electrical field distribution helps in-depth understanding of the mechanisms behind the responses and the benefits of the high voltage pulse comminution. The COMSOL Multiphysics package was used to numerically simulate the effect of ore compositions in this study. Regarding phosphate ore particles shape and composition, the effects of mineral composition, particle size, particle shape and electrodes distance were investigated on the electrical field intensity and distribution. The results show that the induced electrical field is significantly dependent on the electrical properties of minerals,the feed particle size and the location of conductive minerals in ores. The angle of material contact surface with the discharge electrode is also an important factor in the intensity of electrical field. Moreover,it is found that the specific liberation effect at the disintegration of phosphate ore by electrical pulses is due to the locality of the electrical field at the interface of mineral components of the phosphate ore aggregates with different permittivities. However, the intensity of the electrical field increases with sharpening the contact angle. Besides, the electrical discharge in the samples is converted to the electrohydraulic discharge across the surrounding water by changing the distance between the discharge electrode and sample surface.Razavian Seyed Mohammad Rezai Bahram Irannajad Mehdi Ravanji Mohammad Hasan 2015International Journal of Mining Science and Technology2015,25,3:4
20Prediction of meteorological drought in arid and semi-arid regions using PDSI and SDSM: a case study in Fars Province, Iran显示文摘Drought is one of the most significant environmental disasters,especially in arid and semi-arid regions.Drought indices as a tool for management practices seeking to deal with the drought phenomenon are widely used around the world.One of these indicators is the Palmer drought severity index(PDSI),which is used in many parts of the world to assess the drought situation and continuation.In this study,the drought state of Fars Province in Iran was evaluated by using the PDSI over 1995-2014 according to meteorological data from six weather stations in the province.A statistical downscaling model(SDSM)was used to apply the output results of the general circulation model in Fars Province.To implement data processing and prediction of climate data,a statistical period 1995-2014 was considered as the monitoring period,and a statistical period 2019-2048 was for the prediction period.The results revealed that there is a good agreement between the simulated precipitation(R2>0.63;R2,determination coefficient;MAE<0.52;MAE,mean absolute error;RMSE<0.56;RMSE,Root Mean Squared Error)and temperature(R2>0.95,MAE<1.74,and RMSE<1.78)with the observed data from the stations.The results of the drought monitoring model presented that dry periods would increase over the next three decades as compared to the historical data.The studies showed the highest drought in the meteorological stations Abadeh and Lar during the prediction period under two future scenarios representative concentration pathways(RCP4.5 and RCP8.5).According to the results of the validation periods and efficiency criteria,we suggest that the SDSM is a proper tool for predicting drought in arid and semi-arid regions.Sheida DEHGHAN Nasrin SALEHNIA Nasrin SAYARI Bahram BAKHTIARI 2020Journal of Arid Land2020,12,2:4
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