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| 1 | Warpage and Shrinkage Optimization of Injection-Molded Plastic Spoon Parts for Biodegradable Polymers Using Taguchi, ANOVA and Artificial Neural Network Methods显示文摘In this study, it is attempted to give an insight into the injection processability of three self-prepared polymers from A to Z. This work presents material analysis, injection molding simulation, design of experiments alongside considering all interaction effects of controlling parameters carefully for green biodegradable polymeric systems, including polylactic acid(PLA), polylactic acid-thermoplastic polyurethane(PLA-TPU) and polylactic acid-thermoplastic starch(PLA-TPS). The experiments were carried out using injection molding simulation software Autodesk Moldflow?in order to minimize warpage and volumetric shrinkage for each of the mentioned systems. The analysis was conducted by changing five significant processing parameters, including coolant temperature, packing time, packing pressure, mold temperature and melt temperature. Taguchi's L27(35) orthogonal array was selected as an efficient method for design of simulations in order to consider the interaction effects of the parameters and reduce spurious simulations. Meanwhile, artificial neural network(ANN) was also used for pattern recognition and optimization through modifying the processing conditions. The Taguchi coupled analysis of variance(ANOVA) and ANN analysis resulted in definition of optimum levels for each factor by two completely different methods. According to the results, melting temperature, coolant temperature and packing time had significant influence on the shrinkage and warpage. The ANN optimal level selection for minimization of shrinkage and/or warpage is in good agreement with ANOVA optimal level selection results. This investigation indicates that PLA-TPU compound exhibits the highest resistance to warpage and shrinkage defects compared to the other studied compounds. | Erfan Oliaei Behzad Shiroud Heidari Seyed Mohammad Davachi Mozhgan Bahrami Saeed Davoodi Iman Hejazi Javad Seyfi | 2016 | Journal of Materials Science & Technology2016，32，8： | 26 |
| 2 | Optimal PD/PID control of smart base isolated buildings equipped with piezoelectric friction dampers显示文摘Long-period pulses in near-field earthquakes lead to large displacements in the base of isolated structures.To dissipate energy in isolated structures using semi-active control,piezoelectric friction dampers(PFD) can be employed.The performance of a PFD is highly dependent on the strategy applied to adjust its contact force.In this paper,the seismic control of a benchmark isolated building equipped with PFD using PD/PID controllers is developed.Using genetic algorithms,these controllers are optimized to create a balance between the performance and robustness of the closed-loop structural system.One advantage of this technique is that the controller forces can easily be estimated.In addition,the structure is equipped with only a single sensor at the base floor to measure the base displacement.Considering seven pairs of earthquakes and nine performance indices,the performance of the closed-loop system is evaluated.Then,the results are compared with those given by two well-known methods:the maximum possive operation of piezoelectric friction dampers and LQG controllers.The simulation results show that the proposed controllers perform better than the others in terms of simultaneous reduction of floor acceleration and maximum displacement of the isolator.Moreover,they are able to reduce the displacement of the isolator systems for different earthquakes without losing the advantages of isolation. | Sadegh Etedali Mohammad Reza Sohrabi Saeed Tavakoli | 2013 | Earthquake Engineering and Engineering Vibration2013，12，1： | 17 |
| 3 | In-situ solvothermal processing of polycaprolactone/hydroxyapatite nanocomposites with enhanced mechanical and biological performance for bone tissue engineering显示文摘The interest in biodegradable polymer-matrix nanocomposites with bone regeneration potential has been increasing in recent years.In the present work,a solvothermal process is introduced to prepare hydroxyapatite(HA)nanorod-reinforced polycaprolactone in-situ.A non-aqueous polymer solution containing calcium and phosphorous precursors is prepared and processed in a closed autoclave at different temperatures in the range of 60-150℃.Hydroxyapatite nanorods with varying aspect ratios are formed depending on the processing temperature.X-ray diffraction analysis and field-emission scanning electron microscopy indicate that the HA nanorods are semi-crystalline.Energy-dispersive Xray spectroscopy and Fourier transform infrared spectrometry determine that the ratio of calcium to phosphorous increases as the processing temperature increases.To evaluate the effect of in-situ processing on the mechanical properties of the nanocomposites,highly porous scaffolds(>90%)containing HA nanorods are prepared by employing freeze drying and salt leaching techniques.It is shown that the elastic modulus and strength of the nanocomposites prepared by the in-situ method is superior(~15%)to those of the ex-situ samples(blended HA nanorods with the polymer solution).The enhanced bone regeneration potential of the nanocomposites is shown via an in vitro bioactivity assay in a saturated simulated body fluid.An improved cell viability and proliferation is also shown by employing(3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide)(MTT)assay in human osteosarcoma cell lines.The prepared scaffolds with in vitro regeneration capacity could be potentially useful for orthopaedic applications and maxillofacial surgery. | Saeed Moeini Mohammad Reza Mohammadi Abdolreza Simchi | 2017 | Bioactive Materials2017，2，3： | 8 |
| 4 | Vulnerability of ordinary moment resistant concrete frames显示文摘The effects of structural modeling (bar slip in lap splice), ground motion selection process (epsilon effect) and size of a structure (number of bays and stories) on the fragility of reinforced concrete ordinary moment resisting frames are investigated. An analytical model is developed to account for bar slip in lap splice, which exhibits good correlation with existing experimental data. Then, incremental dynamic analysis is used to derive the fragility curves for four model structures. The model structures simulate frames with a different number of bays and stories. Finally, the fragility curves are corrected for the epsilon effect. The results show that slip in the lap splice can significantly increase the failure probability, especially for the collapse prevention limit state. At the same time, it is found that spectral shape has a significant impact on the fragility curves. It is also found that accounting for or ignoring bar slip or epsilon effects increases the probability of failure for larger structures. This indicates an unconservative bias in the safety of larger structures. | Mohammad Barkhordary Saeed Tariverdilo | 2011 | Earthquake Engineering and Engineering Vibration2011，10，4： | 6 |
| 5 | Forecasting soil temperature at multiple-depth with a hybrid artificial neural network model coupledhybrid firefly optimizer algorithm显示文摘Forecasting soil temperature at multiple depths is considered to be a core decision-making task for examining future changes in surface and sub-surface meteorological processes,land-atmosphere energy exchange,resilient agricultural systems for improved crop health and eco-environmental risk assessment.The aim of this paper is to estimate monthly soil temperature(ST)at multiple depth:5,10,20,50 and 100 cm with a hybrid multi-layer perceptron algorithm integrated with the firefly optimizer algorithm(MLP-FFA).To develop the hybrid MLP-FFA model,the monthly ST and relevant meteorological variables for the city of Adana(Turkey)are collated for the period of 2000–2007.Construction of hybrid MLP-FFA model is drawn upon a limited set of predictors,denoted as soil depth,periodicity(or the respective month),air temperature,pressure and solar radiation,while the objective variable for MLP-FFA model is the forecasted ST at multiple depths.To the evaluate MLPFFA,statistical metrics applied to test the model’s performance are:the root mean square error(RMSE),mean absolute error(MAE),mean absolute percentage error(MAPE)and mean bias error(MBE)where the sign of the difference is also considered.In conjunction with statistical metrics,a Taylor diagram is utilized to visualize the degree of similarity between the observed and forecasted soil moisture.In terms of the forecasted results,the hybrid MLPFFA model is seen to outperform the standalone MLP model.The optimal MLP-FFA is attained for soil temperature forecasting at a depth of 20 cm(RMSE,MAPE of 0.546C,2.40%)whereas the optimal MLP is attained for soil temperature forecasting at a depth of 50 cm(RMSE of 0.544℃,2.21%).Conclusively,the study advocates through statistical metrics attained the better utility of the hybrid MLP-FFA hybrid model.Given its superior performance,it is ascertained that the hybrid MLP model integrated with Firefly optimizer is a qualified ancillary tool that can be applied to generate precise soil temperature forecasts at multiple soil depths. | Saeed Samadianfard Mohammad Ali Ghorbani Babak Mohammadi | 2018 | Information Processing in Agriculture2018，5，4： | 5 |
| 6 | Predisposing factors, clinical assessment, management and outcomes of agitation in the trauma intensive care unit显示文摘BACKGROUND: Agitation occurs frequently among critically ill patients admitted to the intensive care unit(ICU). We aimed to evaluate the frequency, predisposing factors and outcomes of agitation in trauma ICU. METHODS: A retrospective analysis was conducted to include patients who were admitted to the trauma ICU between April 2014 and March 2015. Data included patient's demographics, initial vitals, associated injuries, Ramsey Sedation Scale, Glasgow Coma Scale, head injury lesions, use of sedatives and analgesics, head interventions, ventilator days, and ICU length of stay. Patients were divided into two groups based on the agitation status.RESULTS: A total of 102 intubated patients were enrolled; of which 46(45%) experienced agitation. Patients in the agitation group were 7 years younger, had significantly lower GCS and sustained higher frequency of head injuries(P<0.05). Patients who developed agitation were more likely to be prescribed propofol alone or in combination with midazolam and to have frequent ICP catheter insertion, longer ventilatory days and higher incidence of pneumonia(P<0.05). On multivariate analysis, use of propofol alone(OR=4.97; 95% CI=1.35–18.27), subarachnoid hemorrhage(OR=5.11; 95% CI=1.38–18.91) and ICP catheter insertion for severe head injury(OR=4.23; 95% CI=1.16–15.35) were independent predictors for agitation(P<0.01).CONCLUSION: Agitation is a frequent problem in trauma ICU and is mainly related to the type of sedation and poor outcomes in terms of prolonged mechanical ventilation and development of nosocomial pneumonia. Therefore, understanding the main predictors of agitation facilitates early risk-stratification and development of better therapeutic strategies in trauma patients. | Saeed Mahmood Omaima Mahmood Ayman El-Menyar Mohammad Asim Hassan Al-Thani | 2018 | World Journal of Emergency Medicine2018，9，2： | 5 |
| 7 | Elevated alanine aminotransferase activity is not associated with dyslipidemias,but related to insulin resistance and higher disease grades in non-diabetic non-alcoholic fatty liver disease显示文摘Objective:To explore demographic and metabolic factors associated with increased alanine aminotransferase(ALT)activity in non-diabetic non-alcoholic fatty liver disease(NAFLD)patients.Methods:Overall 372 patients who consecutively attended to Gastroenterology Clinic of Baqiyatallah University of Medical Sciences,Tehran,Iran awere diagnosed as NAFLD entered into analysis.Exclusion criteria were having diabetes mellitus and fasting blood glucose over126 mg/dL,active hepatitis B virus infection,having hepatitis C virus positive serology,and to be under corticosteroid therapy.ALT levels were considered pathologically high when it was over30 IU/L for men and over 19 IU/L for women.Results:Bivariate analyses using t test and chisquare test showed that patients with pathologically augmented ALT levels had significantly higher NAFLD grades in their ultrasonographic evaluations(P=0.003).Moreover,these patients represented significantly higher homeostatic model assessment levels(P=0.003),levels of serum insulin(P=0.002),fasting blood glucose(P<0.001),and uric acid(P=0.02).The prevalence of insulin resistance was also higher in patients with increased serum ALT concentrations.Multifactorial logistic regression models showed that ultrasonographic grading of NAFLD(P=0.027)and insulin resistance(P=0.013)were the only variables significantly associated with abnormal ALT levels.Conclusions:This study shows that the associations of increased ALT serum levels in NAFLD patients are different from what are supposed before.By excluding diabetic patients from our population,we find that increased ALT levels are not associated with dyslipidemias but are independently associated with insulin resistance and NAFLD grading on ultrasonographic evaluations.Further studies are needed to confirm our results. | Mohammad Ebrahim Ghamar-Chehreh Mohsen Amini Hossein Khedmat Seyed Moayed Alavian Fatemeh Daraei Reza Mohtashami Reza Hadi Bent-Al-Hoda Beyram Saeed Taheri | 2012 | Asian Pacific Journal of Tropical Biomedicine2012，2，9： | 5 |
| 8 | 纳米氧化铝作为第三层对热障涂层中热生长氧化物层的改善(英文)显示文摘在热障涂层的顶层与连接层界面之间会生成热生长氧化物层。当涂层热暴露在空气中时,这种热生长氧化物的生长会导致陶瓷层与连接层的剥落。研究了4种大气等离子喷涂热障涂层在空气中的耐高温氧化性能。将这4种涂层放在1000°C的电炉中在空气下分别保温24、48和120h。组织观察表明,在纳米NiCrAlY/YSZ/纳米Al2O3涂层中,热生长氧化物层的生长速率远比其它3种涂层中的低。EDS和XRD分析表明,在热生长氧化物(Al2O3)涂层上,生成了Ni(Cr,Al)2O4混合氧化物(尖晶石型)和NiO,在纳米NiCrAlY/YSZ/纳米Al2O3涂层中,这种生长在Al2O3层上的有害混合氧化物层的厚度比在其它涂层中的低很多。 | Mohammadreza DAROONPARVAR Muhamad Azizi Mat YAJID Noordin Mohd YUSOF Saeed FAR AHANY Mohammad Sakhawat HUSSAIN Hamid Reza BAKHSHESHIRAD Z.VALEFI Ahmad ABDOLAHI | 2013 | Transactions of Nonferrous Metals Society of China2013，23，5： | 4 |
| 9 | Effect of alumina content and heat treatment on microstructure and upconversion emission of Er^(3+)ions in oxyfluoride glass-ceramics显示文摘The effect of alumina content and heat treatment temperature and time, on microstructure and Er3+ (0.5 mol.%) emission of oxy-fluoride glass-ceramics were investigated in this research. Two values of 1.8 (SA1.8Er0.5) and 2.18 (SA2.18Er0.5) were selected in this re-search for SiO2/Al2O3 ratio. According to DTA results, precursor glasses were heat treated at 630, 660 and 690 °C for 4 h and some glasses were also heat treated at 630 °C for 48 and 72 h. The results indicated that alumina content had significant effect on phase separation and vis-cosity of the glasses. Therefore the size, size distribution, and volume concentration of nano CaF2 crystals which precipitated during the heat treatment depended on alumina content of the glass. Due to the much smaller size of the precipitated CaF2 crystals in the glasses of low alumina content, these samples maintained excellent transparency and had narrower crystal size distribution than the high alumina glasses. The crystal size was increased markedly with the temperature increasing from 630 to 690 °C. On the other hand a slight increase was observed in the crystal size by raising the heat treatment time in both glasses. Results indicated that in low alumina content glass (SA2.18Er0.5) the size of CaF2 nanocrystals was controlled in one order of magnitude. The increase of heat treatment time and temperature led to the incorporation of Er3+ ions into CaF2 crystalline phase, increasing significantly the upconversion intensity. After heat treatment at 690 ℃ for 4 h, atomic force microscope (AFM) re-vealed the development of small crystals with an average size of 80 and 30 nm in SA1.8Er0.5 and SA2.18Er0.5 samples, respectively. | Mohammad Hasan Imanieh Bijan Eftekhari Yekta Vahak Marghussian Inocencio Rafael Martin Benenzuela Alberto Hernandez Creus Saeed Shakhesi Esmaeil Eslami | 2012 | Journal of Rare Earths2012，30，12： | 3 |
| 10 | 糖尿病患者白内障术后脉络膜厚度和黄斑厚度的变化(英文)显示文摘目的:评估糖尿病和非糖尿病患者白内障超声乳化术后脉络膜厚度(SFCT)和黄斑厚度(CMT)的变化。方法:前瞻性研究。包括53例轻度或中度非增殖性糖尿病视网膜病变(NPDR)无黄斑水肿患者和53例行白内障超声乳化术非糖尿病患者。术前、术后1mo和3mo用 EDI-OCT 测量脉络膜厚度和黄斑厚度,并比较两组的SFCT和CMT变化。结果:糖尿病患者中,基线处CMT为267±32 μm。术后CMT显著升高,术后1mo为291±77 μm( P =0.034),术后3mo为293±75 μm( P =0.047)。基线处SFCT为199± 72 μm 。术后SFCT显著升高,术后1mo为231±73 μm ( P = 0.035),术后3mo为248±91 μm( P =0.026)。在非糖尿病患者中,基线处CMT为264±29 μm。术后显著CMT升高,术后1mo为278±42 μm( P <0.001),术后3mo为 276± 56 μm( P =0.028)。基线处SFCT为236±60 μm。术后SFCT显著提高,术后1mo为265±64 μm( P <0.001),术后3mo为240±60 μm( P =0.234)。两组间CMT的变化无统计学差异(均 P >0.05)。尽管非糖尿病组患者的基线脉络膜较厚,但研究组术后1mo( P =0.97)和术后3mo( P =0.97)的SFCT变化无显著差异。结论:术后两组间CMT和SFCT均显著提高。CMT和SFCT变化在糖尿病和非糖尿病患者间无显著不同。 | Saeed Karimi Mohammad Alizadeh Seyed Aliasghar Mosavi Farinaz Borna | 2019 | 国际眼科杂志2019，19，6： | 3 |
| 11 | Facile synthesis of nanoporous CuS nanospheres for high-performance supercapacitor electrodes显示文摘In recent years, development of high-performance supercapacitor electrode materials has stimulated a great deal of scientific research. The electrochemical performance of a supercapacitor strongly depends on its material structures. Herein, we report a simple strategy for high-performance supercapacitors by building pseudocapacitive CuS nanospheres with nanoporous structures, nanosized walls(<10 nm) and relatively large specific surface area of 65 m^2/g. This electrode demonstrates excellent electrochemical performance including a maximum specific capacitance of 814 F/g at 1 A/g, significant rate capability of 42% capacitance retention at an ultrafast rate of 50 A/g, and outstanding long-term cycling stability at various current densities. The remarkable electrochemical performance of as-prepared nanoporous CuS nanospheres electrode has been attributed to its unique structures that plays a key role in providing short ion and electron diffusion pathways, facilitated ion transport and more active sites for electrochemical reactions. This work sheds a new light on the metal sulfides design philosophy, and demonstrates that nanoporous CuS nanospheres electrode is a promising candidate for application in high-performance supercapacitors. | Hamid Heydari Seyyed Ebrahim Moosavifard Mohammad Shahraki Saeed Elyasi | 2017 | Journal of Energy Chemistry2017，26，4： | 3 |
| 12 | Performance and emission characteristics of a diesel engine operating on different water in diesel emulsion fuels:optimization using response surface methodology(RSM)显示文摘The nitrogen oxide(NOx)release of diesel engines can be reduced using water in diesel emulsion fuel without any engine modification.In the present paper,different formulations of water in diesel emulsion fuels were prepared by ultrasonic irradiation.The water droplet size in the emulsion,polydisperisty index,and the stability of prepared fuel was examined,experimentally.Afterwards,the performance characteristics and exhaust emission of a single cylinder air-cooled diesel engine were investigated using different water in diesel emulsion fuels.The effect of water content(in the range of 5%-10% by volume),surfactant content(in the range of 0.5%-2% by volume),and hydrophilic-lipophilic balance(HLB)(in the range of 5-8)was examined using Box-Behnken design(BBD)as a subset of response surface methodology(RSM).Considering multi-objective optimization,the best formulation for the emulsion fuel was found to be 5%water,2% surfactant,and HLB of 6.8.A comparison was made between the best emulsion fuel and the neat diesel fuel for engine performance and emission characteristics.A considerable decrease in the nitrogen oxide emission(-18.24%)was observed for the best emulsion fuel compared to neat diesel fuel. | Seyed Saeed HOSEINI Mohammad Amin SOBATI | 2019 | Frontiers in Energy2019，13，4： | 3 |
| 13 | Comparison of corneal measurements in keratoconic eyes using rotating Scheimpflug camera and scanning-slit topography显示文摘AIM: To compare the anterior segment measurements obtained by rotating Scheimpflug camera(Pentacam) and Scanning-slit topography(Orbscan IIz) in keratoconic eyes.METHODS: A total of 121 patients, 71 males(58.7%)and 50 females(41.3%)(214 eyes) with the diagnosis of keratoconus(KC) were enrolled in this study. Following diagnosis of KC by slit-lamp biomicroscopic examination, central corneal thickness(CCT), thinnest corneal thickness(TCT), anterior chamber depth(ACD),and pupil diameter(PD) were measured by a single examiner using successive instrumentation by Pentacam and Orbscan.RESULTS: There was no significant difference between the two instruments for the measurement of CCT and TCT. In contrast, scanning-slit topography measured ACD(3.46±0.40 mm vs 3.38±0.33 mm, P =0.019) and PD(4.97 ±1.26 mm vs 4.08 ±1.19 mm, P <0.001) significantly larger than rotating Scheimpflug camera.The two devices made similar measurements for CCT(95% CI:-2.94 to5.06, P =0.602). However, the mean difference for TCT was-6.28(95% CI:-10.51 to-2.06, P =0.004) showing a thinner measurement by Orbscan than by Pentacam. In terms of the ACD, the mean difference was 0.08 mm(95%CI: 0.04 to 0.12, P <0.001) with Orbscan giving a slightly larger value than Pentacam. Similarly, Orbscan measurement for PD was longer than Pentacam(95% CI:0.68 to 1.08, P <0.001).CONCLUSION: A good agreement was found between Pentacam and Orbscan concerning CCT measurement while comparing scanning-slit topography and rotatingScheimpflug camera there was an underestimation for TCT and overestimation for ACD and PD. | Mohammad Naderan Saeed Shoar Morteza Naderan Mohammad Amin Kamaleddin Mohammad Taher Rajabi | 2015 | International Journal of Ophthalmology(English edition)2015，8，2： | 3 |
| 14 | Characterization of porous Ti-bioglass composite produced by mechanical milling and space holder sintering显示文摘In this study, porous titanium-10 wt% bioglass(BG) composites were fabricated by the process of combining mechanical alloying with space holder sintering. The pore morphology and phase constituents of the milled powders and porous compacts were characterized by scanning electron microscopy(SEM), X-ray diffractometry(XRD), and Fourier transform infrared spectroscopy(FT-IR). The mechanical properties were determined by running compression test. The porosity of the sintered samples shows a downward trend with the increase of milling time. As the porosity increases, both the compressive strength and elastic modulus decrease. The results illustrate that the fabricated porous compacts with high porosity and suitable mechanical properties have the potential application in bone tissue engineering. | Saeed Riahi Mohammad Rajabi Sayed Mahmood Rabiee | 2015 | Rare Metals2015，34，9： | 3 |
| 15 | Silica supported sodium hydrogen sulfate(NaHSO_4/SiO_2):A mild and efficient reusable catalyst for the synthesis of aryl-14-H-dibenzo[a,j]xanthenes under solvent-free conditions显示文摘A simple and efficient procedure for the preparation of aryl-14-H-dibenzo[a,j]xanthenes by a one-pot condensation reaction of 2-naphthol and aryl aldehydes,in the presence of silica supported sodium hydrogen sulfate(NaHSO_4/SiO_2)as a catalyst and in the absence of solvent has been developed.The present method offers several advantages such as excellent yields,short reaction time (10-30 min),mild condition,simple work-up,and the use of a cheap and environmentally friendly catalyst with remarkable reusability. | Shahnaz Rostamizadeh Nasrin Shadjou Ali Mohammad Amani Saeed Balalaie | 2008 | Chinese Chemical Letters2008，19，10： | 3 |
| 16 | 二氧化锡纳米粒子催化四组分Hantzsch缩合合成多氢喹啉衍生物(英文)显示文摘Tin dioxide (SnO2 ) nanoparticles efficiently catalyzed unsymmetrical four-component Hantzsch condensations of various aldehydes, dimedone, ethyl acetoacetate, and ammonium acetate to form polyhydroquinoline derivatives in excellent yields. This novel method offers several advantages over the traditional method of synthesizing these compounds, including safety, mild conditions, short reaction times, high yields, and an easy workup. | Seyed Mohammad VAHDAT Fereshteh CHEKIN Mehdi HATAMI Maryam KHAVARPOUR Saeed BAGHERY Ziba ROSHAN‐KOUHI | 2013 | 催化学报2013，34，4： | 2 |
| 17 | A new Monte Carlo code for absorption simulation of laser-skin tissue interaction显示文摘In laser clinical applications,the process of photon absorption and thermal energy diffusion in the target tissue and its surrounding tissue during laser irradiation are crucial.Such information allows the selection of proper operating parameters such as laser power,and exposure time for optimal therapeutic.The Monte Carlo method is a useful tool for studying laser-tissue interaction and simulation of energy absorption in tissue during laser irradiation.We use the principles of this technique and write a new code with MATLAB 6.5,and then validate it against Monte Carlo multi layer (MCML) code.The new code is proved to be with good accuracy.It can be used to calculate the total power absorbed in the region of interest.This can be combined for heat modelling with other computerized programs. | Afshan Shirklvand Saeed Sarlcar Marjaneh Hejazi Leila Ataie-Fashtami Mohammad Reza Alinaghizadeh | 2007 | Chinese Optics Letters2007，5，4： | 2 |
| 18 | Free fatty acids receptors 2 and 3 control cell proliferation by regulating cellular glucose uptake显示文摘BACKGROUND Colorectal cancer(CRC)is a worldwide problem,which has been associated with changes in diet and lifestyle pattern.As a result of colonic fermentation of dietary fibres,short chain free fatty acids are generated which activate free fatty acid receptors(FFAR)2 and 3.FFAR2 and FFAR3 genes are abundantly expressed in colonic epithelium and play an important role in the metabolic homeostasis of colonic epithelial cells.Earlier studies point to the involvement of FFAR2 in colorectal carcinogenesis.AIM To understand the role of short chain FFARs in CRC.METHODS Transcriptome analysis console software was used to analyse microarray data from CRC patients and cell lines.We employed short-hairpin RNA mediated down regulation of FFAR2 and FFAR3 genes,which was validated using quantitative real time polymerase chain reaction.Assays for glucose uptake and cyclic adenosine monophosphate(cAMP)generation was done along with immunofluorescence studies to study the effects of FFAR2/FFAR3 knockdown.For measuring cell proliferation,we employed real time electrical impedancebased assay available from xCELLigence.RESULTS Microarray data analysis of CRC patient samples showed a significant down regulation of FFAR2 gene expression.This prompted us to study the FFAR2 in CRC.Since,FFAR3 shares significant structural and functional homology with FFAR2,we knocked down both these receptors in CRC cell line HCT 116.These modified cell lines exhibited higher proliferation rate and were found to have increased glucose uptake as well as increased level of glucose transporter 1.Since,FFAR2 and FFAR3 signal through G protein subunit(Gαi),knockdown of these receptors was associated with increased cAMP.Inhibition of protein kinase A(PKA)did not alter the growth and proliferation of these cells indicating a mechanism independent of cAMP/PKA pathway.CONCLUSION Our results suggest role of FFAR2/FFAR3 genes in increased proliferation of colon cancer cells via enhanced glucose uptake and exclude the role of PKA mediated cAMP signalling.Alternate pathways could be involved that would ultimately result in increased cell proliferation as a result of down regulated FFAR2/FFAR3 genes.This study paves the way to understand the mechanism of action of short chain FFARs in CRC. | Saeed Al Mahri Amal Al Ghamdi Maaged Akiel Monira Al Aujan Sameer Mohammad Mohammad Azhar Aziz | 2020 | World Journal of Gastrointestinal Oncology2020，12，5： | 2 |
| 19 | 传统溶剂提取法和超临界流体萃取法对钟花蒲桃次生代谢产物的回收率的比较研究(英文)显示文摘目的:寻求一种最佳的钟花蒲桃次生代谢产物的萃取方法,以实现在工业上的应用。创新点:全面深入地比较传统溶剂提取法和超临界流体萃取法对钟花蒲桃的主要次生代谢产物的回收率。方法:在超临界流体萃取法中,应用Box-Behnken设计,以压力、温度和萃取粒径大小为自变量,以粗提取物、个别的和总的次生代谢产物的百分比产量为因变量。另外,还研究了调节剂乙醇对产量的影响。在传统溶剂提取中,结合十种不同的溶剂和三不同的技术(浸提、索氏和回流)产生二十种不同的提取产物。通过高效液相色谱法检测不同的提取方法对钟花蒲桃的主要次生代谢产物的回收率。结论:超临界流体萃取法优于传统溶剂提取法,省成本又省时。因此在工业使用上,超临界流体萃取法可替代传统溶剂提取法。 | Abdul Hakeem MEMON Mohammad Shahrul Ridzuan HAMIL Madeeha LAGHARI Fahim RITHWAN Salman ZHARI Mohammed Ali Ahmed SAEED Zhari ISMAIL Amin Malik Shah Abdul MAJID | 2016 | Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)2016，17，9： | 2 |
| 20 | Effects of operating parameters on oxidative coupling of methane over Na-W-Mn/SiO_2 catalyst at elevated pressures显示文摘The effects of operating parameters on oxidative coupling of methane (OCM) over Na-W-Mn/SiO2 catalyst have been studied at elevated pressures of 0.2, 0.3 and 0.4 MPa under low gaseous hourly space velocity (GHSV) and low temperature conditions. Experimental results show that when the operating pressure is increased, C2+ yield slightly decreases, while the maximum ratio of ethylene to ethane remains unchanged. Moreover, it has been found empirically that increase of pressure does not affect the catalyst behavior permanently, the catalyst recovers its original low pressure performance without hysteresis behavior by reducing the pressure. Under the investigated conditions, when oxygen is completely consumed, the increase of GHSV leads to improvement in C2 selectivity, while C3+ and COx selectivities decrease slightly. The C2+ selectivity increases by increase of nitrogen diluent in the feed, but the C3+ hydrocarbons selectivities decrease with increase of nitrogen since it is possible that further dilution at high pressure may reduce the probability of collision between CH3 and C2+ hydrocarbons. During the stability test at high pressure, the catalyst performance remains unchanged throughout the 20 h running. The fresh and used catalysts were characterized using XRD, SEM and N2 adsorption-desorption methods. It was found that the phase transformation of the support from α-cristobalite to tridymite and quartz does not have obvious effect on catalyst performance at high pressure. | Jafar Sadeghzadeh Ahari Mohammad Taghi Sadeghi Saeed Zarrinpashne | 2011 | Journal of Natural Gas Chemistry2011，20，2： | 2 |
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