Graduate University of Advanced Technology

About: Graduate University of Advanced Technology is a education organization based out in Kerman, Iran. It is known for research contribution in the topics: Carbon paste electrode & Electrochemical gas sensor. The organization has 890 authors who have published 2169 publications receiving 31027 citations.

Intraspecific differences in plant chemotype determine the structure of arthropod food webs

Abstract: It is becoming increasingly appreciated that the structure and functioning of ecological food webs are controlled by the nature and level of plant chemicals. It is hypothesized that intraspecific variation in plant chemical resistance, in which individuals of a host-plant population exhibit genetic differences in their chemical contents (called ‘plant chemotypes’), may be an important determinant of variation in food web structure and functioning. We evaluated this hypothesis using field assessments and plant chemical assays in the tansy plant Tanacetum vulgare L. (Asteraceae). We examined food webs in which chemotypes of tansy plants are the resource for two specialized aphids, their predators and mutualistic ants. The density of the ant-tended aphid Metopeurum fuscoviride was significantly higher on particular chemotypes (borneol) than others. Clear chemotype preferences between predators were also detected. Aphid specialist seven-spotted ladybird beetles (Coccinella septempunctata) were more often found on camphor plants, while significantly higher numbers of the polyphagous nursery web spider (Pisaura mirabilis) were observed on borneol plants. The analysis of plant chemotype effects on the arthropod community clearly demonstrates a range of possible outcomes between plant-aphid-predator networks. The findings help to offer a deeper insight into how one important factor—plant chemical content—influences which species coexist within a food web on a particular host plant and the nature of their trophic linkages.

Fabrication of Fast and Sensitive Nanostructure Voltammetric Sensor for Determination of Curcumin in the Presence of Vitamin B9 in Food Samples

Abstract: A novel voltammetric sensor was used for the determination of curcumin by using cadmium oxide nanoparticles-ionic liquid (1,3-dipropylimidazolium bromide as a binder) modified carbon paste electrode (CdO-IL-MCPE). At pH 7.0 as an optimum electrochemical condition, the oxidation signals for curcumin and vitamin B9 are separated at ca. 0.41 and 0.73 V respectively; facilitating fast and sensitive analysis of curcumin in presence of vitamin B9. The oxidation signal of curcumin represented a linear relationship with the concentration of curcumin (R2=0.9981) in the range of 0.2–320.0 µM, with a detection limit of 0.08 µM.

Facile Hydrothermal Synthesis of Magnetic Sepiolite Clay for Removal of Pb(II) from Aqueous Solutions

Abstract: The sepiolite-iron oxide nanocomposite (Sepiolite-Fe3O4) was synthesized via facile hydrothermal method and used as an efficient magnetic adsorbent for removal of Pb(II) ions from water samples. The Sepiolite-Fe3O4 nanocomposite was characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), transmission electron microscopy (TEM), vibration sample magnetometer (VSM) and scanning electron microscopy (SEM) techniques. The equilibrium data were tested using different isotherm models including Langmuir, Freundlich and Temkin. The adsorption isotherm fits well with the Langmuir model and the maximum Pb(II)-sorption capacity of 96.15 mg g-1 was calculated at room temperature. Kinetic data well interpreted with the pseudo-second-order model (R2 > 0.9998), that illustrated the adsorption process was controlled by chemical reactions. The as-prepared magnetic adsorbent was easily reused through sequential adsorption-desorption cycles, presenting that the Sepiolite-Fe3O4 nanocomposite has an acceptable stability and reusability. As a result, this study indicates that the novel adsorbent nanocomposite may be an ideal adsorbent for heavy metal-contaminated water treatment.

Highly Sensitive Nanostructured Electrochemical Sensor Based on Carbon Nanotubes-Pt Nanoparticles Paste Electrode for Simultaneous Determination of Levodopa and Tyramine

Abstract: A multicomponent electrochemical sensor, with two nanometer-scale components in sensing matrix/electrode, was used to simultaneous determination of levodopa (LD) and tyramine (TR) in pharmaceutical and diet samples. Multiwall carbon nanotubes (MWCNTs) were used as carbonaceous materials in the electrode construction. 5-amino-3',4'-dimethoxy-biphenyl-2-ol (5ADMB) was used as electron mediator and Pt nanoparticles (nPt) as a catalyst. The 5ADMB catalyzes the oxidation of LD to the corresponding catecholamine, which is electrochemically reduced back to LD. Preparation of this electrode was very simple and modified electrode showed good properties at electrocatalytic oxidization of LD and TR. Using differential pulse voltammetry (DPV), a highly selective and simultaneous determination of LD and TR has been explored at the modified electrode. Differential pulse voltammetry peak currents of LD and TR increased linearly with their concentrations at the ranges of 0.50–100.0 μM and 0.60–100.0 μM, respectively. Also, the detection limits for LD and TR were 0.31 and 0.52 μM, respectively. The electrode exhibited an efficient catalytic response with good reproducibility and stability.

A modified efficient method for dental pulp stem cell isolation.

Abstract: Background: Dental pulp stem cells can be used in regenerative endodontic therapy. The aim of this study was to introduce an efficient method for dental pulp stem cells isolation. Materials and Methods: In this in-vitro study, 60 extracted human third molars were split and pulp tissue was extracted. Dental pulp stem cells were isolated by the following three different methods: (1) digestion of pulp by collagenase/dispase enzyme and culture of the released cells; (2) outgrowth of the cells by culture of undigested pulp pieces; (3) digestion of pulp tissue pieces and fixing them. The cells were cultured in minimum essential medium alpha modification (αMEM) medium supplemented with 20% fetal bovine serum(FBS) in humid 37°C incubator with 5% CO2. The markers of stem cells were studied by reverse transcriptase polymerase chain reaction (PCR). The student t-test was used for comparing the means of independent groups. P <0.05 was considered as significant. Results: The results indicated that by the first method a few cell colonies with homogenous morphology were detectable after 4 days, while in the outgrowth method more time was needed (10-12 days) to allow sufficient numbers of heterogeneous phenotype stem cells to migrate out of tissue. Interestingly, with the improved third method, we obtained stem cells successfully with about 60% efficiency after 2 days. The results of RT-PCR suggested the expression of Nanog, Oct-4, and Nucleostemin markers in the isolated cells from dental pulps. Conclusion: This study proposes a new method with high efficacy to obtain dental pulp stem cells in a short time. Key Words: Dental pulp stem cells, isolation, method, molar