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1Phase 1 human trial of autologous bone marrow-hematopoietic stem cell transplantation in patients with decompensated cirrhosis显示文摘AIM: To evaluate safety and feasibility of autologous bone marrow-enriched CD34+ hematopoietic stem cell Tx through the hepatic artery in patients with decompensated cirrhosis.METHODS: Four patients with decompensated cirrhosis were included. Approximately 200 mL of the bone marrow of the patients was aspirated, and CD34+ stem cells were selected. Between 3 to 10 million CD34+ cells were isolated. The cells were slowly infused through the hepatic artery of the patients.RESULTS: Patient 1 showed marginal improvement in serum albumin and no significant changes in other test results. In patient 2 prothrombin time was decreased; however, her total bilirubin, serum creatinine, and Model of End-Stage Liver Disease (MELD) score worsened at the end of follow up. In patient 3 there was improvement in serum albumin, porthrombin time (PT), and MELD score. Patient 4 developed radiocontrast nephropathy after the procedure, and progressed to type 1 hepatorenal syndrome and died of liver failure a few days later. Because of the major side effects seen in the last patient, the trial was prematurely stopped.CONCLUSION: Infusion of CD34+ stem cells through the hepatic artery is not safe in decompensated cirrhosis. Radiocontrast nephropathy and hepatorenal syndrome could be major side effects. However, this study doesnot preclude infusion of CD34+ stem cells through other routes.Mehdi Mohamadnejad Mehrnaz Namiri Mohamad Bagheri Seyed Masiha Hashemi Hossein Ghanaati Narges Zare Mehrjardi Saeed Kazemi Ashtiani Reza Malekzadeh Hossein Baharvand 2007World Journal of Gastroenterology2007,13,24:74
2Review on Zinc Oxide Nanoparticles: Antibacterial Activity and Toxicity Mechanism显示文摘Antibacterial activity of zinc oxide nanoparticles(Zn O-NPs) has received significant interest worldwide particularly by the implementation of nanotechnology to synthesize particles in the nanometer region. Many microorganisms exist in the range from hundreds of nanometers to tens of micrometers. Zn O-NPs exhibit attractive antibacterial properties due to increased specific surface area as the reduced particle size leading to enhanced particle surface reactivity. Zn O is a bio-safe material that possesses photo-oxidizing and photocatalysis impacts on chemical and biological species. This review covered Zn O-NPs antibacterial activity including testing methods, impact of UV illumination, Zn O particle properties(size, concentration, morphology, and defects), particle surface modification, and minimum inhibitory concentration. Particular emphasize was given to bactericidal and bacteriostatic mechanisms with focus on generation of reactive oxygen species(ROS) including hydrogen peroxide(H2O2), OH-(hydroxyl radicals), and O2-2(peroxide). ROS has been a major factor for several mechanisms including cell wall damage due to Zn O-localized interaction, enhanced membrane permeability, internalization of NPs due to loss of proton motive force and uptake of toxic dissolved zinc ions.These have led to mitochondria weakness, intracellular outflow, and release in gene expression of oxidative stress which caused eventual cell growth inhibition and cell death. In some cases, enhanced antibacterial activity can be attributed to surface defects on Zn O abrasive surface texture. One functional application of the Zn O antibacterial bioactivity was discussed in food packaging industry where Zn O-NPs are used as an antibacterial agent toward foodborne diseases. Proper incorporation of Zn O-NPs into packaging materials can cause interaction with foodborne pathogens, thereby releasing NPs onto food surface where they come in contact with bad bacteria and cause the bacterial death and/or inhibition.Amna Sirelkhatim Shahrom Mahmud Azman Seeni Noor Haida Mohamad Kaus Ling Chuo Ann Siti Khadijah Mohd Bakhori Habsah Hasan Dasmawati Mohamad 2015Nano-Micro Letters2015,7,3:76
3Hepatocellular carcinoma in Asia: Prevention strategy and planning显示文摘AIM: To review all of epidemiological and etiological aspects of hepatocellular carcinoma(HCC) and examined the prevention of this disease in Asia.METHODS: We conducted a systematic review according to the PRISMA guidelines. We were chosen articles that published previously, from Pub Med(MEDLINE), the Cochrane database and Scopus. The key words used in this research were as follows: HCC in Asia and the way of prevention of this disease, with no language limitations. We selected those papers published before 2014 that we considered to be most important and appropriate. All relevant articles were accessed in full text and all relevant materials was evaluated and reviewed.RESULTS: More than 70% of all new cases of liver cancer were diagnosed in Asia, a region that 75% of all those chronically infected with hepatitis B virus(HBV) in the world. Chronic HBV infection is the main cause of HCC in Asia, where the virus is endemic and vertical transmission is common. Japan, Saudi Arabia, Egypt and Pakistan are exception because of high prevalence of HCV infection in these regions. The prevalence of this cancer is high in Eastern and South-Eastern Asia, But Middle Eastern countries are characterized as moderate prevalence rate of HCC region and Central Asia and some part of Middle Eastern countries are known as low prevalence rate of HCC. In addition of HBV and HCV the other factors such as aflatoxin, alcohol, obesity, diabetes and non-alcoholic fatty liver disease(NAFLD) might be responsible for a low prevalence of HCC in Asian countries. Currently available HCC therapies, chemotherapy, surgical are inefficient, mainly due to usually late diagnosis and high recurrence rates after surgical resection, and usually end with treatment failure. Liver transplantation also remains as a difficult strategy in patients with HCC. Thus prevention of HCC by treating and prevention HBV and HCV infection, the major causative agents of HCC, and the other riskfactors such as aflatoxin, alcohol, obesity, diabetes and NAFLD is of a great medical importance. CONCLUSION: The main challenge which still present in Asia, is the high prevalence of chronic hepatitis.So, prevention of HBV and HCV is the key strategy to reduce the incidence of HCC in Asia.Sara Ashtari Mohamad Amin Pourhoseingholi Afsaneh Sharifian Mohamad Reza Zali 2015World Journal of Hepatology2015,7,12:25
4在亚洲的 colorectal 癌症的增加的负担显示文摘 The incidence and mortality of colorectal cancer(CRC) is rising rapidly in Asia.It seems that ethnicity has an important etiological role in CRC in Asia.However the incidence,anatomical distribution and mortality of CRC among Asian populations are not different from those in Western countries.There is little support by health authorities for CRC screening and very low public awareness of this emerging epidemic in Asia.The increasing rate of CRC in Asia means that we need to take action immediately to prevent CRC and to diagnose the disease at the early stages by introducing CRC screening in countries at high risk of an increasing burden of CRC.Mohamad Amin Pourhoseingholi 2012World Journal of Gastrointestinal Oncology2012,4,4:18
5Pancreatico-biliary endoscopic ultrasound:A systematic review of the levels of evidence,performance and outcomes显示文摘Our aim was to record pancreaticobiliary endoscopic ultrasound(EUS) literature of the past 3 decades and evaluate its role based on a critical appraisal of published studies according to levels of evidence(LE).Original research articles(randomized controlled trials,prospective and retrospective studies),meta-analyses,reviews and surveys pertinent to gastrointestinal EUS were included.All articles published until September 2011 were retrieved from PubMed and classified according to specific disease entities,anatomical subdivisions and therapeutic applications of EUS.The North of England evidencebased guidelines were used to determine LE.A total of 1089 pertinent articles were reviewed.Published research focused primarily on solid pancreatic neoplasms,followed by disorders of the extrahepatic biliary tree,pancreatic cystic lesions,therapeutic-interventional EUS,chronic and acute pancreatitis.A uniform observation in all six categories of articles was the predominance of LE Ⅲ studies followed by LE Ⅳ,Ⅱb,Ⅱa,Ⅰb and Ⅰ a,in descending order.EUS remains the most accurate method for detecting small(< 3 cm) pancreatic tumors,ampullary neoplasms and small(< 4 mm) bile duct stones,and the best test to define vascular invasion in pancreatic and peri-ampullary neoplasms.Detailed EUS imaging,along with biochemical and molecular cyst fluid analysis,improve the differentiation of pancreatic cysts and help predict their malignant potential.Early diagnosis of chronic pancreatitis appears feasible and reliable.Novel imaging techniques(contrast-enhanced EUS,elastography) seem promising for the evaluation of pancreatic cancer and autoimmune pancreatitis.Therapeutic applications currently involve pancreaticobiliary drainage and targeted fine needle injection-guided antitumor therapy.Despite the ongoing development of extra-corporeal imaging modalities,such as computed tomography,magnetic resonance imaging,and positron emission tomography,EUS still holds a leading role in the investigation of the pancreaticobiliary area.The major challenge of EUS evolution is its expanding therapeutic potential towards an effective and minimally invasive management of complex pancreaticobiliary disorders.Pietro Fusaroli Dimitrios Kypraios Giancarlo Caletti Mohamad A Eloubeidi 2012World Journal of Gastroenterology2012,18,32:17
6枸杞化学成分及药用价值国外研究现状显示文摘枸杞(Lycium barbarum)一直被用作重要的中药材和食品补充剂。查阅相关文献,对枸杞的化学成分及其药用价值的国外研究进行了综述,发现枸杞含有大量的氨基酸、维生素、纤维素、矿物质、微量元素、多糖和多种生物活性物质,这些物质使得枸杞具有丰富的营养和多种生物活性;具有抗癌、抗动脉硬化、抗肿瘤、抗增殖、抗氧化、保护中枢神经系统等作用,可以预防慢性疾病如高胆固醇、糖尿病、肝炎、眼病、皮疹、牛皮癣、过敏、失眠、慢性肝病、糖尿病、肺结核和肾脏疾病等,还具有提高免疫力,预防衰老,增加新陈代谢,抗氧化等保健功能。孙文丽 Mohamad Hesam Shahrajabian 程奇 2020中医药信息2020,37,3:17
7双向电泳-质谱技术筛选肝癌血清标记物显示文摘采用双向电泳-质谱技术筛选肝癌特异的血清蛋白标记物,以利于肝癌的早期诊断和治疗.肝癌、肝炎和正常三组各20例血清先采用超声、高丰度蛋白去除、脱盐预处理以优化双向电泳,图像分析三组血清图谱寻找差异点,基质辅助激光解吸飞行时间质谱对差异点进行鉴定.结果显示,通过样品预处理,血清上样体积平均增加3~4倍,参考胶点数由218个增至332个,白蛋白和免疫球蛋白明显减弱,水平条带明显减少.图谱比较所得37个差异点,经鉴定为7种蛋白.与正常组比较,转铁蛋白、甲状腺素运载蛋白在肝炎和肝癌组低表达,α-1抗胰蛋白酶、凝聚素、铜蓝蛋白、触珠蛋白在肝炎和肝癌组均高表达.α-1抗胰蛋白酶在肝癌组较肝炎组高表达,而热休克蛋白27只在肝癌组表达.上述结果提示,双向电泳-质谱技术可发现肝癌发生发展过程中血清蛋白表达谱质或量的变化,从而为肝癌的早期诊断及治疗奠定基础.冯钜涛 刘银坤 MOHAMAD RADWAN ALMOFTI 代智 周海君 宋海燕 陆豪杰 汤钊猷 2005生物化学与生物物理进展2005,32,7:15
8Endoscopic ultrasound evaluation in the surgical treatment of duodenal and peri-ampullary adenomas显示文摘AIM:To investigate endoscopic ultrasound(EUS) for predicting depth of mucosal invasion and to analyze outcomes following endoscopic and transduodenal resection.METHODS:Records of 111 patients seen at our institution from November 1999 to July 2011 with the postoperative pathological diagnosis of benign ampullary and duodenal adenomas were reviewed.Records of patients who underwent preoperative EUS for diagnostic purposes were identified.The accuracy of EUS in predicting the absence of muscular invasion was assessed by comparing EUS reports to the final surgical pathological results.In addition,the incidence of the post-operative complications over a period of 30 d and the subsequent long-term outcome(recurrence) over a period of 30 mo associated with endoscopic and transduodenal surgical resection was recorded,compared and analyzed.RESULTS:Among 111 patients with benign ampullary and duodenal adenomas,47 underwent preoperative EUS for 29 peri-ampullary lesions and 18 duodenal lesions.In addition,computed tomography was performed in 18 patients,endoscopic retrograde cholangio-pancreatography in 10 patients and esophagogastroduodenoscopy in 22 patients.There were 43 patients with sporadic adenomas and 4 patients with familial adenomatous polyposis(FAP)/other polyposis syndromes.In 38(81%,P < 0.05) patients,EUS reliably identified absence of submucosal and muscularis invasion.In 4 cases,EUS underestimated submucosal invasion that was proven by pathology.In the other 5 patients,EUS predicted muscularis invasion which could not be demonstrated in the resected specimen.EUS predicted tumor muscularis invasion with a specificity of 88% and negative predictive value of 90%(P < 0.05).Types of resection performed included endoscopic resection in 22 cases,partial duodenectomy in 9 cases,transduodenal ampullectomy with sphincteroplasty in 10 cases and pancreaticoduodenectomy in 6 cases.The main post-operative final pathological results included villous adenoma(n = 5),adenoma(n = 8),tubulovillous adenoma(n = 10),tubular adenoma(n = 20) and hyperplastic polyp(n = 2).Among the 47 patients who underwent resection,8(17%,5 of which corresponded to surgical resection) developed post-procedural complications which included retroperitoneal hematoma,intra-abdominal abscess,wound infection,delayed gastric emptying and prolonged ileus.After median followup of 20 mo there were 6 local recurrences(13%,median follow-up = 20 mo) 4 of which were in patients with FAP.CONCLUSION:EUS accurately predicts the depth of mucosal invasion in suspected benign ampullary and duodenal adenomas.These patients can safely undergo endoscopic or local resection.Lilian C Azih Brett L Broussard Milind A Phadnis Martin J Heslin Mohamad A Eloubeidi Shayam Varadarajulu Juan Pablo Arnoletti 2013World Journal of Gastroenterology2013,19,4:13
9Risk assessment for the daily intake of polycyclic aromatic hydrocarbons from the ingestion of cockle (Anadara granosa) and exposure to contaminated water and sediments along the west coast of Peninsular Malaysia显示文摘The concentration of carcinogenic polycyclic aromatic hydrocarbons (c-PAHs) present in the sediment and water of Peninsular Malaysia as well as in the cockle Anadara granosa was investigated.Samples were extracted and analysed with gas chromatographymass spectrometry.The concentrations of total carcinogenic polycyclic aromatic hydrocarbons (t-PAHs) were measured between 0.80 ± 0.04 to 162.96 ± 14.74 ng/g wet weight (ww) in sediment,between 21.85 ± 2.18 to 76.2 ± 10.82 ng/L in water samples and between 3.34 ± 0.77 to 46.85 ± 5.50 ng/g ww in the cockle tissue.The risk assessment of probable human carcinogens in the Group B2 PAHs was calculated and assessed in accordance with the standards of the United States Environmental Protection Agency (US EPA).Case I in the toxicity assessment analysed the cancer risk to consumers of Malaysian blood cockle.Case II assessed the risk of cancer from exposure to PAHs from multiple pathways.The average cancer risk of case I and case II were found to be classifiable as unsafe according to the US EPA standard.The cancer risk due to c-PAHs acquired by the ingestion of blood cockle was (8.82 ± 0.54) × 10-6 to (2.67 ± 0.06) × 10-2,higher than the US EPA risk management criterion.The non-cancer risks associated with multiple pathways in Kuala Gula,Kuala Juru and Kuala Perlis were higher than the US EPA safe level,but the non-cancer risk for eating blood cockle was below the level of US EPA concern.Seiedeh Aghileh Mirsadeghi Mohamad Pauzi Zakaria Chee Kong Yap Azadeh Shahbazi 2011Journal of Environmental Sciences2011,23,2:11
10Non-alcohol fatty liver disease in Asia:Prevention and planning显示文摘AIM:To review all of epidemiological aspects of nonalcoholic fatty liver disease(NAFLD) and also prevent this disease is examined.METHODS:We conducted a systematic review according to the PRISMA guidelines.All searches for writing this review is based on the papers was found in Pub Med(MEDLINE),Cochrane database and Scopus in August and September 2014 for topic of NAFLD in Asia and the way of prevention of this disease,with no language limitations.All relevant articles were accessed in full text and all relevant materials was evaluated and reviewed.RESULTS:NAFLD is the most common liver disorder in worldwide,with an estimated with 20%-30% prevalence in Western countries and 2%-4% worldwide.The prevalence of NAFLD in Asia,depending on location(urban vs rural),gender,ethnicity,and age is variable between 15%-20%.According to the many studies in the world,the relationship between NAFLD,obesity,diabetes mellitus,and metabolic syndrome(MS) is quiet obvious.Prevalence of NAFLD in Asian countries seems to be lower than the Western countries but,it has increased recently due to the rise of obesity,type 2 diabetes and MS in this region.One of the main reasons for the increase in obesity,diabetes and MS in Asia is a lifestyle change and industrialization.Today,NAFLD is recognized as a major chronic liver disease in Asia.Therefore,prevention of this disease in Asian countries is very important and the best strategy for prevention and control of NAFLD is lifestyle modifications.Lifestyle modification programs are typically designed to change bad eating habits and increase physical activity that is associated with clinically significant improvements in obesity,type 2 diabetes and MS.CONCLUSION:Prevention of NAFLD is very importantin Asian countries particularly in Arab countries because of high prevalence of obesity,diabetes and MS.Sara Ashtari Mohamad Amin Pourhoseingholi Mohamad Reza Zali 2015World Journal of Hepatology2015,7,13:10
11Incidence and predictors of radial nerve palsy with the anterolateral brachialis splitting approach to the humeral shaft显示文摘Mohamad Gouse Sandeep Albert Dan Barnabas Inja Manasseh Nithyananth 2016Chinese Journal of Traumatology2016,19,4:9
12Urban livability across disciplinary and professional boundaries显示文摘Mohamad Kashef 2016Frontiers of Architectural Research2016,5,2:9
13Fatty liver without a large“belly”:Magnified review of nonalcoholic fatty liver disease in non-obese patients显示文摘Nonalcoholic fatty liver disease(NAFLD) is well described as a common cause of chronic liver disease, mostly in the obese population. It refers to a spectrum of chronic liver disease that starts with simple steatosis than progresses to nonalcoholic steatohepatitis and cirrhosis in patients without significant alcohol consumption. NAFLD in the non-obese population has been increasingly reported and studied recently. The pathogenesis of nonobese NAFLD is poorly understood and is related to genetic predisposition, most notably patatin-like phospholipase domain-containing 33 G allele polymorphism that leads to intrahepatic triglyceride accumulation and insulin resistance. Nonobese NAFLD is associated with components of metabolic syndrome and, especially, visceral obesity which seems to be an important etiological factor in this group. Dietary factors and, specifically, a high fructose diet seem to play a role. Cardiovascular events remain the main cause of mortality and morbidity in NAFLD, including in the nonobese population. There is not enough data regarding treatment in non-obese NAFLD patients, but similar to NAFLD in obese subjects, lifestyle changes that include dietary modification, physical activity, and weight loss remain the mainstay of treatment.Mohamad H Yousef Alhareth Al Juboori Abdulmajeed A Albarrak Jamal A Ibdah Veysel Tahan 2017World Journal of Gastrointestinal Pathophysiology2017,8,3:9
14An intelligent system for egg quality classification based on visible-infrared transmittance spectroscopy显示文摘The potential of the visible infrared(Vis–IR)(400–1100 nm)transmittance method to assess the internal quality(freshness)of intact chicken egg during storage at a temperature of 30±7C and 25±4%relative humidity was investigated.Two hundred chicken egg samples were used for measuring freshness and spectra collection during egg storage(up to 25 days).Two correlation models,firstly between Haugh unit(HU)and storage time,and secondly between the yolk coefficient(YC)and storage time,were developed and yielded correlation coefficients(R^2)of 0.86 and 0.96,respectively.These models spanned the period for which egg quality decreased dramatically and are statistically significant(P<0.05).In addition,to reduce the dimensionality of the spectra and extract effective wavelengths,two methods were developed based on principal component analysis(PCA)and a genetic algorithm(GA).The output of PCA and GA were also used comparatively to design an egg quality intelligent system.The result of the analyses indicated that identification ratio of GAwith fast Fourier transform(FFT)preprocessing was superior to other methods,and that the quality classification rates of this method for one-day-old eggs are 100%.This study shows that identification of an egg’s freshness using NIR spectroscopy with GA and artificial neural network(ANN)is reliable.Saman Abdanan Mehdizadeh Saeid Minaei Nigel H.Hancock Mohamad Amir Karimi Torshizi 2014Information Processing in Agriculture2014,1,2:8
15新疆药用植物牛至内生细菌多样性与抗菌活性显示文摘【背景】植物内生菌作为微生物群落中一类非常重要的组成部分,在多个领域都有广泛的应用价值,如促进植物生长、抵抗病虫害、生物固氮、降解有毒有害化合物等。【目的】进一步丰富新疆野果林苹果腐烂病害的生防资源以及分析牛至内生细菌多样性特征。【方法】通过纯培养方法,对健康植物牛至组织进行内生细菌的分离纯化,并进行16S rRNA基因序列分析;再利用平板对峙法筛选具有抑制苹果腐烂病病原菌生长的内生细菌。【结果】共分离到168株内生细菌,最终确定为4门5纲8目12科17属,其中优势属为芽胞杆菌属(Bacillus)。由分离实验结果可知,M1号TSA培养基,M5号组氨酸-棉子糖培养基和M6号NA培养基是分离牛至内生细菌较为理想的培养基;采自新源县野果林的牛至内生细菌多样性较为丰富,在牛至根部内生细菌种类更多;通过拮抗实验共筛选出59株牛至内生细菌具有较好的抑菌效果。【结论】新疆药用植物牛至内生细菌的物种多样性较为丰富,而且富含一批有效抑制野苹果腐烂病病原菌生长的内生细菌菌株。因此,本研究在新疆野果林苹果腐烂病的生物防治和药用植物内生细菌种质资源的填补等方面具有重要意义。高磊 刘永红 马金彪 Osama Abdalla Abdelshafy Mohamad 李文均 李丽 2021微生物学通报2021,48,4:8
16Effect of Alkali and Silane Treatments on Mechanical and Fibre-matrix Bond Strength of Kenaf and Pineapple Leaf Fibres显示文摘Mohammad Asim Mohammad Jawaid Khalina Abdan Mohamad Ridzwan lshak 2016Journal of Bionic Engineering2016,13,3:8
17牛支原体TaqMan探针实时荧光定量PCR检测方法的建立及应用显示文摘以牛支原体p80基因为靶基因,设计特异性引物与探针,优化反应体系,建立了牛支原体TaqMan探针实时荧光定量PCR(TaqMan real-time PCR)检测方法,并对该方法进行了特异性、敏感性、重复性评估以及临床样本检测。结果显示,特异性试验中,牛支原体2个菌株Cq值均小于18,其余13个非牛支原体菌株Cq值均大于36;敏感性试验中,最低可检3.89拷贝/μL靶DNA,是普通PCR的10~4倍(普通PCR 3.89×10~4拷贝/μL);重复性试验中,组内、组间重复的变异系数均小于1%;44份牛的临床样品利用TaqMan real time PCR检出6份阳性(阳性率为13.64%),分离培养鉴定检出7份阳性,普通PCR检测全部阴性。本研究建立了一种敏感、特异、稳定的牛支原体TaqMan real time PCR检测方法,可用于牛支原体的快速诊断和核酸定量检测。翟肖辉 王方国 郝华芳 颜新敏 陈胜利 Hussam Askar Mohamad 朱建勋 储岳峰 2019畜牧与兽医2019,0,8:8
18Artificial Intelligence in Healthcare:Review and Prediction Case Studies显示文摘Artificial intelligence(AI)has been developing rapidly in recent years in terms of software algorithms,hardware implementation,and applications in a vast number of areas.In this review,we summarize the latest developments of applications of AI in biomedicine,including disease diagnostics,living assistance,biomedical information processing,and biomedical research.The aim of this review is to keep track of new scientific accomplishments,to understand the availability of technologies,to appreciate the tremendous potential of AI in biomedicine,and to provide researchers in related fields with inspiration.It can be asserted that,just like AI itself,the application of AI in biomedicine is still in its early stage.New progress and breakthroughs will continue to push the frontier and widen the scope of AI application,and fast developments are envisioned in the near future.Two case studies are provided to illustrate the prediction of epileptic seizure occurrences and the filling of a dysfunctional urinary bladder.Guoguang Rong Arnaldo Mendez Elie Bou Assi Bo Zhao Mohamad Sawan 2020Engineering2020,6,3:7
19Vegetation composition differentiation and species-environment relationships in the northern part of Isfahan Province, Iran显示文摘A considerable proportion of Iran's territory is covered with arid and semi-arid rangelands and mismanagement and overexploitation of those rangelands have resulted in serious ecological degradation. Thus, the need is pressing to examine the present species composition and the relationships with environmental factors for providing the needed scientific references to species conservation and ecological rehabilitation efforts. The aims of this study were to examine the species composition and to delineate the most important factors influencing the distributions of plant species and groups in the northern rangelands of Isfahan Province(Iran) using two-way indicator species analysis(TWINSPAN), detrended correspondence analysis(DCA), principal component analysis(PCA), and canonical correspondence analysis(CCA). Field investigations were conducted in the growing season of 2014 using stratified random method in 22 homogeneous sampling units. In total, 75 plant species belonging to 52 genera and 19 families were identified. The most important families were Asteraceae and Papilionaceae, the most important genera were Astragalus, Cousinia, and Acanthophyllum, and the most important species were Artemisia aucheri and Artemisia sieberi. Plant species were classified into 10 groups using TWINSPAN. DCA was used to estimate the magnitude of changes in species composition along the first two ordination axes to provide gradient length estimations for PCA and CCA ordinations. The first three PCA axes and the first three CCA axes demonstrated similar cumulative percentage of variance, indicating that the environmental factors(selected by PCA) used in CCA ordination were acceptable for explaining the species composition and the distributions. CCA ordination showed that the first axis was closely related to elevation, slope, surface bare soil cover, surface litter cover, gravel proportion, organic matter, total nitrogen, Ca CO3 content, and grazing intensity and that the second axis was closely related to sand proportion, silt proportion, clay proportion, and saturation percentage. Among these factors, elevation was the most effective factor to separate the plant groups and grazing was the major cause of rangeland degradation.Hadi KARGAR-CHIGANI Seyed Akbar JAVADI Ghavamodin ZAHEDI-AMIRI Seyed Jamaleddin KHAJEDDIN Mohamad JAFARI 2017Journal of Arid Land2017,9,2:7
20Application of nano silica to improve self-healing of asphalt mixes显示文摘Nano silica due to its spherical shape, tiny size and higher density compared to bitumen, may have an inherent potential to improve hot mix asphalt(HMA) self-healing. In this research scanning electron microscopy(SEM) images were used to investigate size, morphology and dispersion of nano silica particles. Additionally, HMA self-healing mechanism was also examined by SEM. Furthermore, dynamic indirect tensile test(IDT) was used to evaluate HMA self-healing index. The SEM results indicated that bitumen mortar flowing into micro cracks may be one of the most important mechanisms of HMA self-healing. The experiment results also showed that modification of bitumen by nano silica promotes the ability of the HMA self-healing.Ganjei Mohamad Amin Aflaki Esmail 2017Journal of Central South University2017,24,5:7
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