[en] Graphical abstract: - Highlights: • Graphene/nano-Au composite was synthesized by electrochemical co-reduction method in one step. • Glucose oxidase achieves direct electrochemistry on the graphene/nano-Au composite film. • The glucose biosensor shows a high sensitivity of 56.93 μA mM"−"1 cm"−"2 toward glucose. • Glucose was detected with a wide linear range and low detection limit. - Abstract: A simple, green and controllable approach was employed for electrochemical synthesize of the graphene/nano-Au composites. The process was that graphene oxide and HAuCl_4 was electrochemically co-reduced onto the glassy carbon electrode (GCE) by cyclic voltammetry in one step. The obtained graphene/nano-Au/GCE exhibited high electrocatalytic activity toward H_2O_2, which resulted in a remarkable decrease in the overpotential of H_2O_2 electrochemical oxidation compared with bare GCE. Such electrocatalytic behavior of the graphene/nano-Au/GCE permitted effective low-potential amperometric biosensing of glucose via the incorporation of glucose oxidase (GOD) with graphene/nano-Au. An obvious advantage of this enzyme electrode (graphene/nano-Au/GOD/GCE) was that the graphene/nano-Au nanocomposites provided a favorable microenvironment for GOD and facilitated the electron transfer between the active center of GOD and electrode. The immobilized GOD showed a direct, reversible redox reaction. Furthermore, the graphene/nano-Au/GOD/GCE was used as a glucose biosensor, displaying a low detection limit of 17 μM (S/N = 3), a high sensitivity of 56.93 μA mM"−"1 cm"−"2, acceptable reproducibility, very good stability, selectivity and anti-interference ability

[en] Highlights: • CuO-rGO nanocomposites was synthesized with a facile, green and effective chemical method. • The nonenzymatic modified electrode achieved electrocatalytic oxidation towards glucose. • The glucose sensor shows a high sensitivity of 2221 μA mM⁻¹ cm⁻² towards glucose. • Glucose was detected with a wide linear range and low detection limit. - Abstract: A novel, stable and sensitive non-enzymatic glucose biosensor based on nanocomposites of copper oxide (CuO) and the reduced graphene oxide (rGO) was developed. A facile, green and effective chemical method was employed to synthesize the CuO-rGO nanocomposites in a mixture solution of water-isopropanol. During the synthesis process, isopropanol acted as both solvent and reductant. CuO nanoparticles were successfully decorated onto the graphene oxide (GO) sheets through electrostatic force and hydrolysis reaction. Meantime, GO could be partly reduced to the rGO without any addition of strong reduction agents. The information on the structure and topology of as-prepared CuO-rGO nanocomposites was characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), Raman spectroscopy, and its electrochemical catalytical performance was also studied. The results indicated that CuO-rGO nanocomposites could display a synergistic effect of rGO sheets and CuO nanoparticles towards the electro-oxidation of glucose in the alkaline solution, leading to a remarkable decrease in the overpotential of the glucose oxidation. At the applied potential of 0.4 V, the CuO-rGO film modified glassy carbon electrode (CuO/rGO/GCE) presented a high sensitivity of 2221 μA mM⁻¹ cm⁻² and a wide linear range from 0.4 μM to 12 mM towards glucose with good selectivity and stability

[en] The point flux integral method and point estimated method are two effective variance reduction techniques in Monte-Carlo analog computation. They are especially useful in the calculation of small probability. (authors)

[en] To investigate the changes of mice behavior ability before and after 8 Gy γ-ray irradiation, and to provide the scientific basics for establishing nuclear-irradiate-critical-dose standard of pilot in the war, mice round-the-clock activity was measured and observed

[en] To study the key measures of controlling the indoor radon hazards, the physical and chemical properties of radon, influence of ventilation on indoor radon level and contents of radon in building materials were discussed. It is less effective to only employ the remedial measures after construction and decoration of residence to reduce the indoor radon hazards. The key of controlling the indoor radon hazards is to decrease the sources of radon, especially selecting the zone of low radon content to build residence and using low radon content building materials. (authors)

[en] The purpose of this paper is to evaluate the value of ¹⁸F-FDG PET metabolic imaging and ^99mTc-MIBI SPECT in the identification of myocardial viability in patients with previous myocardial infarction and left ventricular dysfunction. ¹⁸F-FDG PET (made in China) and ^99mTc-MIBI SPECT were performed in 60 patients (pts) (age 54±9 yr) with myocardial infarction before revascularization. Before and after revascularization, LVEF and wall motion were measured with echocardiography in 36 pts (Group A), and myocardial perfusion was evaluated in 24 pts (Group B). According to the interpretation of perfusion and metabolic images, myocardial segments were classified into mismatch (MM): reduced myocardial perfusion and normal FDG uptake or match (M): reduced perfusion and FDG uptake. Out of 264 segments with hypoperfusion, 145 (54.9%) were MM, suggesting viable myocardium (G-A1 and G-B1), 119 (45.1%) were M, suggesting necrosis (G-A2 and G-B2). After revascularization, LVEF was increased in G-A1 (49±15% vs. 59±7%, p<0.05), and in G-B1 (50±8% vs. 59±12%, p<0.05), but was not improved in G-A2 and G-B2. LVEDD was decreased in G-A1 and G-B1 (p<0.05) and was unchanged in G-A2 and G-B2. The positive predictive value (PPV) of FDG PET for improvement of regional wall motion after revascularization was 88%, and the negative predictive value (NPV) was 72.6%. The PPV for improvement of perfusion was 84.1%, NPV was 85%, and accuracy was 84.4%. ¹⁸F-FDG imaging with Chinese PET has clinical value for assessing myocardial viability and identifying patients who will benefit from revascularization. (author)

[en] Solid phase microextraction-surface enhanced Raman spectroscopy (SPME–SERS), combining the pretreatment and determination functions, has been successfully used in environmental analysis. In this work, Au-coated ZnO nanorods were fabricated on stainless steel fiber as a self-cleaning SERS-active SPME fiber. The ZnO nanorods grown on stainless steel fiber were prepared via a simple hydrothermal approach. Then the obtained nanostructures were decorated with Au nanoparticles through ion-sputtering at room temperature. The obtained SERS-active SPME fiber is a reproducible sensitivity sensor. Taking p-aminothiophenol as the probe molecule, the RSD value of the SERS-active SPME fiber was 8.9%, indicating the fiber owned good uniformity. The qualitative and quantitative detection of crystal violet and malachite green was also achieved. The log–log plot of SERS intensity to crystal violet and malachite green concentration showed a good linear relationship. Meanwhile, this SERS-active SPME fiber can achieve self-cleaning owning to the excellent photocatalytic performance of ZnO nanorods. Crystal violet was still successfully detected even after five cycles, which indicated the high reproducibility of this SERS-active SPME fiber. - Graphical abstract: Au-coated ZnO NRs on stainless steel fiber were used as SERS-active SPME fiber with good extraction effect, high SERS sensitivity. Self-cleaning function of the fiber was achieved based on the photocatalytic degradation property of ZnO nanorods by UV irradiation. - Highlights: • Au-coated ZnO nanorods on stainless steel fiber as a SERS-active SPME fiber was fabricated. • The SERS-active SPME fiber can directly extract and detect the crystal violet and malachite green. • The SERS-active SPME fiber owns good extraction effect, and high SERS sensitivity. • Self-cleaning property of the fiber were achieved based on the photocatalytic degradation property of ZnO.

[en] Objective: To assess the value of stress-rest ⁹⁹Tc^m-MIBI (ST-RE) SPECT imaging for evaluation of perfusion improvement, prediction of restenosis (RS) and cardiac event rate in patients after percutaneous transluminal coronary angioplasty (PTCA). Methods: ⁹⁹Tc^m-MIBI ST-RE SPECT imaging was performed on 100 patients [(52 +- 9) years old] (14 +- 15) months after PTCA. On 30 of the 100 patients, ST-RE SPECT imaging were also performed before PTCA, and 30 patients underwent coronary angiography (CAG). The perfusion findings of myocardial segments were qualitatively classified into four patterns: normal (N), reversible defect (RD), partial reversible defect (PRD) and fixed defect (FD). Restenosis was predicted on the basis of RD or PRD. During the follow-up, cardiac death, myocardial infarction (MI), unstable angina and revascularization were considered as cardiac events. Results: 1) Among 100 patients, RD or PRD was observed in 28 patients, indicating myocardial ischemia (IS); FD was observed in 20 patients, indicating MI. The rate of occurrence of ischemic segments had no significant difference between patients with or without MI(P>0.05). 2) Among 30 patients, perfusion imaging was improved in 23 patients, the improved rate was 76.7%. The number of ischemic segments was decreased from 100 (37%) before PTCA to 10 (3.7%) after PTCA (P<0.000 1). 3) RS was detected in 12 of 30 patients or in 20 of 45 vessels. Sensitivity, specificity, positive predictive value and negative predictive value and accuracy of ST-RE SPECT for predicting RS were 83.3%, 92.0%, 88.8%, 85.1% and 86.7%, respectively. 4) During follow-up, rate of cardiac event was 46.4% (13/28) in ischemic group and that was significantly higher than that in non-ischemic group (1.4%, 1/72, P<0.000 1). Conclusions: ST-RE ⁹⁹Tc^m-MIBI SPECT is a useful noninvasive method for evaluating the effect of PTCA and for predicting RS, and it is of high value for predicting cardiac events

[en] Purpose: To assess the value of ¹⁸F-FDG metabolic imaging with positron emission tomography (PET) in assessment of myocardial viability in patients with previous myocardial infarction (OMI). Methods: ¹⁸F-FDG imaging and ^99mTc-MIBI perfusion imaging were performed in 90 consecutive patients (55.8 +- 9.6 yr) with OMI. After revascularization, left ventricular function was reassessed with echocardiography in 36 patients (Group A), myocardial perfusion imaging as well as echocardiography were performed in 24 patients (Group B). Results: According to the interpretation of perfusion and metabolic images, myocardial segments were classified as mismatch (MM): reduced myocardial perfusion but normal FDG uptake; partial mismatch (PM) and match (M): reduced both perfusion and FDG uptake. Out of 397 segments with hypoperfusion, 201 (50.9%) were MM, suggesting myocardial viable (subgroup A2 and B2), 139(35%) were M, suggesting myocardial necrosis (subgroup A1 and B1). After revascularization, LVEF was increased in subgroup A2 (from 49.5% +- 15.8% to 58.6% +- 13.9%, P<0.05) and in subgroup B2 (from 50.4% +- 58.4% to 58.6% +- 12.2%, P<0.05). However, LVEF was unchanged in subgroup A1 and B1. The positive predictive value (PPV) for improvement of regional wall motion after revascularization was 87.5%, the negative predictive value (NPV) was 71.4%. The PPV for improvement of perfusion was 83.8% and the NPV was 84.6% and the total accuracy was 84.1%. Conclusions: ¹⁸F-FDG PET imaging provides a sensitive and specific method in assessing myocardial viability and identifying the patients who will be likely to benefit from revascularization

[en] Purpose: To evaluate the diagnosis value of pulmonary radionuclide imaging for acute pulmonary embolism (APE). Methods: 10 patients with suspected APE underwent pulmonary perfusion, ventilation, thrombus imaging and radionuclide venography, four out of them underwent pulmonary angiography and electron beam CT as well, in order to obtain more reference data. All 10 patients were reexamined with pulmonary perfusion or thrombus imaging after thrombolysis. Results: The diagnostic positive rate of pulmonary imaging was 100%, which was accordant with the results of X-ray. Pulmonary images after thrombolysis showed that the pulmonary blood flow perfusion was improved, even returned to normal. Conclusions: Radionuclide imaging is an effective and noninvasive method for diagnosing APE and evaluating therapeutic efficiency of thrombolysis