Lead uptake by new silica-carbon nanoparticles

Silica-carbon nanoparticles (SCNP) were prepared from sonication of silica and anthracene. The size of homogenous nanoparticle is around 5-20 nm confirmed by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM). SEM analysis indicated surface porosity. SCNP were used to remove lead ions (Pb(II)) from aqueous solutions. Adsorption isotherm of Pb(II) on SCNP was well fitted in terms of the Freundlich and Langmuir models. The maximum adsorption capacity of SCNP for Pb(II) was found to be 385 mg/g (1.86 mmol/g) in batch experiment. Thermodynamic studies indicated that sorption process of lead onto SCNP was spontaneous and exothermic. A pseudo-second order model has been employed in order to describe the kinetic adsorption processes, and the thermodynamic activation parameters were calculated. In a column studies, qy the Yan adsorption capacity of SCNP for Pb(II) was found to be 130.66 mg/g (0.63 mmol/g)

Synthesis of Novel Yb x

Yb-doped Sb2Te3 nanomaterials were synthesized by a coreduction method in hydrothermal condition. Powder X-ray diffraction patterns indicate that the YbxSb2−xTe3 crystals (x=0.00–0.05) are isostructural with Sb2Te3. The cell parameter a decreases for YbxSb2−xTe3 compounds upon increasing the dopant content (x), while c increases. Scanning electron microscopy and transmission electron microscopy images show that doping of Yb3+ ions in the lattice of Sb2Te3 produces different morphology. The electrical conductivity of Yb-doped Sb2Te3 is higher than the pure Sb2Te3 and increases with temperature. By increasing concentration of the Yb3+ ions, the absorption spectrum of Sb2Te3 shows red shifts and some intensity changes. In addition to the characteristic red emission peaks of Sb2Te3, emission spectra of doped materials show other emission bands originating from f-f transitions of the Yb3+ ions. The photocatalytic performance of as-synthesized nanoparticles was investigated towards the decolorization of Malachite Green solution under visible light irradiation

Diagnostic accuracy of coronary calcium score less than 100 in excluding coronary artery disease

Background: Coronary artery calcium score (CACS) is a quantitative assessment of calcifications and an established predictor of cardiovascular events. Objectives: In this study, we evaluated the diagnostic accuracy, negative predictive value (NPV), positive predictive value (PPV), specificity and sensitivity of CACS less than 100 in predicting significant coronary artery stenosis in patients with risk of coronary artery disease (CAD) in a vessel-based analysis. Patients and Methods: A cross sectional study was carried out on a study population of 2527 consecutive stable patients with symptoms suggestive of CAD who were referred for coronary computed tomographic angiography (CCTA). We performed 1343 studies with 256 slice machine in Shahid Rajaee hospital and the other studies were carried out with 64 slice machine in Imam Khomeini hospital and the calcium score was quantified according to the Agatston method. Results: At the cutoff point of 100 for coronary calcium scoring, therewashigh specificity (87), high sensitivity (79), high efficiency (84), high PPV (79), and high NPV (87) in the diagnosis of significant stenosis in the whole heart. The frequency of zero calcium scoring was 59 in normal or nonsignificant stenosis and 7.6 in significant stenosis in the whole heart. Calcium scoring increased with greater severity of the arterial stenosis (P values < 0.001). Conclusion: We conclude that coronary calcium scoring provided useful information in the management of patients. In CACS less than 100, it has a NPV of 87 in excluding significant stenosis in patients with the risk of CAD but it does not have enough diagnostic accuracy for surely excluding coronary stenosis, so we should perform a combination of CACS and coronary CT angiography for patients. � 2016, Tehran University of Medical Sciences and Iranian Society of Radiology

Hydrothermal Synthesis of Sb 2

Crystalline antimony sulfide (Sb2S3) with nanorods morphology was successfully prepared via hydrothermal method by the reaction of elemental sulfur, antimony, and iodine as starting materials with high yield at 180∘C for 24 h. Using oxidation reagent like iodine as an initiator of redox reaction to prepare Sb2S3 is reported for first time. The powder X-ray diffraction pattern shows the Sb2S3 crystals belong to the orthorhombic phase with calculated lattice parameters, a=1.120 nm, b=1.128 nm, and c=0.383 nm. The quantification of energy-dispersive X-ray spectrometry analysis peaks gives an atomic ratio of 2 : 3 for Sb : S. TEM and SEM studies reveal the appearance of the as-prepared Sb2S3 is rodlike which is composed of nanorods with the typical width of 50–140 nm and length of up to 4 μm. The PL emission indicates that band gap of Sb2S3 is around 2.50 ev, indicating a considerable blue shift relative to the bulk. A formation mechanism of Sb2S3 nanostructure is proposed

No-isolated high gain DC/DC converter with low input current ripple suitable for renewable applications

In this paper, a new non-isolated high voltage gain dc/dc converter with low input current ripple is proposed for renewable sources applications. The proposed converter combined SEPIC converter and voltage multiplier cells. In order to achieve high voltage gain, the proposed converter can increase the output voltage level using the voltage multiplier unit. The voltage stress across the semiconductors will be decreased compared to SEPIC, conventional boost converter. Therefore, using only one switch with lower resistance RDS(on), the overall efficiency of the proposed converter is increased significanly. In order to verify the theoretical analysis of the proposed converter and its accurate operation, a 150 W prototype operating at 25 kHz is built and tested

Serological and Molecular Diagnosis of Toxoplasma gondii Infections in Thalassemia Patients.

BACKGROUND: This study aimed to the serological and molecular diagnosis of Toxoplasma gondii infections and related risk factors in patients with thalassemia major and healthy controls. METHODS: This case-control study was performed in Shahrekord University of Medical Sciences, Shahrekord, west of Iran from Jan 2014 to Jan 2015. Overall, 235 patients with thalassemia major and 235 healthy controls were enrolled. Assessment of anti-Toxoplasma antibodies in sera samples was performed using commercial ELISA kits. In order to the molecular investigate of T. gondii in blood samples, a relatively new molecular assay, LAMP technique based on Toxoplasma SAG1 gene was conducted for the first time. The specificity of LAMP outer primers for the T. gondii detection was confirmed by sequencing the purified PCR product. RESULTS: 51.9% of thalassemia patients and 34.8% of healthy controls were positive for anti-Toxoplasma IgG antibodies, which the difference was statistically significant (P<0.01). In terms of anti-Toxoplasma IgM antibody, 3.4% of thalassemia patients and 2.1% of healthy individuals were positive, which the difference was not statistically significant (P=1). Based on SAG1-LAMP, 9.78% of the thalassemia patients and 5.95% of healthy controls were positive for T. gondii DNA, which the difference was not statistically significant (P≤0.230). CONCLUSION: Thalassemia patients, probably due to repeated blood transfusion and consequently, immune deficiency, are at risk of transmitting Toxoplasma infection more than healthy people. Therefore, screening of Toxoplasma infection in blood transfusion centers may be effective in the prevention of toxoplasmosis in these patients. KEYWORDS: Loop-mediated isothermal amplification; Serology; Thalassemia major; Toxoplasma gondi

Serological and Molecular Diagnosis of Toxoplasma gondii Infections in Thalassemia Patients

Background: This study aimed to the serological and molecular diagnosis of Toxoplasma gondii infections and related risk factors in patients with thalassemia major and healthy controls. Methods: This case-control study was performed in Shahrekord University of Medical Sciences, Shahrekord, west of Iran from Jan 2014 to Jan 2015. Overall, 235 patients with thalassemia major and 235 healthy controls were enrolled. Assessment of anti-Toxoplasma antibodies in sera samples was performed using commercial ELISA kits. In order to the molecular investigate of T. gondii in blood samples, a relatively new molecular assay, LAMP technique based on Toxoplasma SAG1 gene was conducted for the first time. The specificity of LAMP outer primers for the T. gondii detection was confirmed by sequencing the purified PCR product. Results: 51.9% of thalassemia patients and 34.8% of healthy controls were positive for anti-Toxoplasma IgG antibodies, which the difference was statistically significant (P<0.01). In terms of anti-Toxoplasma IgM antibody, 3.4% of thalassemia patients and 2.1% of healthy individuals were positive, which the difference was not statistically significant (P=1). Based on SAG1-LAMP, 9.78% of the thalassemia patients and 5.95% of healthy controls were positive for T. gondii DNA, which the difference was not statistically significant (P≤0.230). Conclusion: Thalassemia patients, probably due to repeated blood transfusion and consequently, immune deficiency, are at risk of transmitting Toxoplasma infection more than healthy people. Therefore, screening of Toxoplasma infection in blood transfusion centers may be effective in the prevention of toxoplasmosis in these patients