[en] Gated cardiac blood-pool imaging in 20 normal controls and 31 patients with CAD (including 17 patients with angina pectoris and 14 patients with myocardiac infarction MI) before and after sublingual NTG were presented to investigate the LV function especially the LV diastolic pattern. Abnormal peak filling rate (PFR) at rest was found in 88.2% patients with angina pectoris, though most of them (86.7%) had normal LV ejection fraction (LVEF) at rest. Abnormal LVEF and PFR at rest were found in all of the patients with MI. Patients with angina pectoris had their LVEF and PFR increased obviously after sublingual NTG. Patients with MI had only their LVEF increased slightly while PFR unchanged after sublingual NTG. Compaired with the group of controls, many patients with CAD showed abnormal PFR at rest while their LVEF were normal. Therefore, PFR is more sensitive than LVEF for the detection of CAD. We concluded the test of NTG can be applied to differentiate angina pectorris and MI, and also can be used differentiate reversible versus irreversible abnormal ventricular segmental contraction

[en] SDC (Sm_0_._2Ce_0_._8O_1_._9)-LNC ((Li_0_._5_2Na_0_._4_8)_2CO_3) nanocomposites with various LNC volume fractions (0.0, 0.3, 0.4, 0.5, 0.6, 0.7 and 1.0) and MgO-50LNC composites were prepared by prefiring and sintering at different temperatures. The XRD, FESEM and TEM techniques were employed to characterize their phase components and microstructures. The AC impedance spectroscopy and DC polarization method were used to measure their electrical conductivities under different conditions. It has been found that the carbonate phase in the MgO-LNC composites is homogeneously crystallized, whereas amorphous carbonate is always identified in the SDC-LNC composites and shown to form an interface layer of ∼6 nm in thickness at the surface of SDC crystallites due to the strong interactions between SDC and LNC phases. The protonic, oxide ionic and overall ionic conductivities of LNC phase were measured at the different temperatures from 450 to 650 °C and then adopted to study the contributions of the interfacial interaction between SDC and LNC phase to the enhanced electrical conductivity of SDC-50LNC composites. The interfacial interactions were found to significantly enhance the protonic and oxide ionic conductivities in the SDC-LNC composites regardless of the remarkable suppressing effect on the migrations of metal ions as the majority mobile charged species in the molten LNC phase. Furthermore, based on a microstructural model of randomly-packed SDC/LNC composite particles and the Maxwell-Garnet mixture rule, the protonic and oxide ionic conductivities of the interface layer was successfully found to reach as high as 97 mS/cm and 46 mS/cm at 650 °C, respectively, through a non-linear least-squares data analysis.

[en] The multiplicity distribution, multiplicity moment, scaled variance, entropy and reduced entropy of target evaporated fragments emitted in forward and backward hemispheres in 150 AMeV ⁴He-AgBr, 290 AMeV ¹²C-AgBr, 400 AMeV ¹²C-AgBr, 400 AMeV ²⁰Ne-AgBr and 500 AMeV ⁵⁶Fe-AgBr interactions are investigated. It is found that the multiplicity distribution of target evaporated fragments emitted in both forward and backward hemispheres can be fitted by a Gaussian distribution. The multiplicity moments of target evaporated particles emitted in the forward and backward hemispheres increase with the order of the moment q, and the second-order multiplicity moment is energy independent over the entire energy range for all the interactions in the forward and backward hemisphere. The scaled variance, a direct measure of multiplicity fluctuations, is close to one for all the interactions, which indicate a weak correlation among the target evaporated fragments. The entropy of target evaporated fragments emitted in forward and backward hemispheres are the same respectively for all of the interactions,within experimental errors. (authors)

[en] 13 total gastrectomy (TG) cases with Roux-Y esophagojejunostomy and 12 subtotal gastrectomy (STG) cases with Billroth II gastrojejunostomy were examined with ^99mTc-PHY semisolid gastrointestinal imaging. The gastric half emptying time (GHET) and mean intestinal transit time (MITT) were analyzed. The GHET of normal subjects (NOR), STG and TG group were 33.7, 19.65 and 8.3 min respectively. There was significant difference between them (P<0.05). The MITT of NOR, STG and TG was 197.4, 202.58 and 237.22, respectively. The MITT in TG was significantly slower than that of NOR (P<0.01) and STG (P<0.05). This report provided a new valuable method for detecting gastrointestinal function disorders

[en] ^99mTc-MIBI myocardial SPECT imaging of 25 normal subjects and 70 patients with CHD were presented and analysed with polar Bullseye plot (PBP). The extent and severe scores in infarcted area were calculated automatically by computer. the sensitivity of tomography and PBP for detecting stenosed coronary arteries were 0.857 and 0.904 respectively (P>0.05). The specificities of both techniques were the same (0.911). However, as compared with visual analysis of the images, obviously the PBP was objective, quantitative and easy to analyse. Some technical hints were also discussed

[en] Heart phantom and clinical study of ^99mTc-MIBI SPECT with 180 degree (LAO to RAO) data acquisition was carried out and compared with the full 360 degree rotation. Data analyses included myocardial volume and area, defect volume and area. In simple heart phantom study, 360 degree acquisition was more approximate to phantom determined true value (P>0.05). However, when a heart phantom was wrapped in a chest phantom, 180 degree data acquisition was more accordant with true value (P>0.05). In 34 cases with coronary heart disease, all of the quantitative parameters mentioned above were very accordant between 360 degree/6 degree and 180 degree/6 degree, 180 degree/6 degree and 180 degree/3 degree. The defect-to normal wall-count ratio (D/N) was lower in the 180 degree scan (0.235 +- 0.043) than in the 360 degree scan (0.249 +- 0.057) (P<0.05), indicating the lesion site can be better detected by the former method. All of the results suggested that for myocardial SPECT the 180 degree acquisition method can save acquisition time and is more practical in the clinical appliance than 360 degree acquisition

[en] Highlights: • t-C₈B₂N₂ is a potential superhard material with I-4m2 space group and its theoretical bulk modulus, shear modules, Young’s modulus, Poisson’s ratio and Vickers hardness are almost same to those of well-known superhard material c-BN. A potential superhard material C₈B₂N₂ with I-4m2 space group is found and confirmed to be stable with first-principles calculations. The results show that its structure is highly incompressible with bulk modulus of 383.4 GPa and shear modulus of 383.0 GPa. It shows that this material is nearly isotropy with universal anisotropy index of 0.056, and its fractional anisotropy ratio of shear modulus and bulk modulus are 0.0055 and 0.0, respectively. Interestingly, its theoretical bulk modulus, shear modules, Young’s modulus, Poisson’s ratio and Vickers hardness are almost same to those of well-known superhard material c-BN.

[en] When evolution algorithms are used to unfold the neutron energy spectrum, fitness function design is an important fundamental work for evaluating the quality of the solution, but it has not attracted much attention. In this work, we investigated the performance of eight fitness functions attached to the genetic algorithm (GA) and the differential evolution algorithm (DEA) used for unfolding four neutron spectra selected from the IAEA 403 report. Experiments show that the fitness functions with a maximum in the GA can limit the ability of the population to percept the fitness change, but the ability can be made up in the DEA. The fitness function with a feature penalty term helps to improve the performance of solutions, and the fitness function using the standard deviation and the Chi-squared result shows the balance between the algorithm and the spectra. The results also show that the DEA has good potential for neutron energy spectrum unfolding. The purposes of this work are to provide evidence for structuring and modifying the fitness functions and to suggest some genetic operations that should receive attention when using the fitness function to unfold neutron spectra.

[en] Three-phase bone imaging was performed in 38 patients with primary bone tumors. The results showed that the lesion-to-nonlesion (L/N) ratios of malignant group in blood flow, blood pool and delay phase were higher than those of benign group. It seems that the blood supply and the metabolic activity of bone salt in malignancy are higher than those of bvenign one. using the mean ratio of blood-flow phase plus 1SD in benign group as a diagnostic demaraction between benign and malignancy, the sensitivity, specificity and accuracy of diagnosis were 88%, 94% and 91% respectively. Therefore, the L/N ratio of blood flow phase has some help for the differentiation between benign and malignancy in primany bone tumors

[en] Three methods of calculating LVCF from ^99mTc-MIBI studies are proposed and analysed. 12 normal subjects and 48 patients with coronary heart disease (CHD) underwent ^99mTc-MIBI myocardial imaging, including tomography (SPECT) and planar gated scintigraphy, and radionuclide ventriculography (RNV). All data were correlated to LVEF and myocardial defect size (DF) measured by SPECT. The results showed that the reproducibility of count mode which was based on the end systolic increase in myocardial count density to calculate LVCF was best of all three methods. The corresponding correlation coefficients (r), standard errors (S_x-bar) and the regression line were as follows (in %): LVCF = 0.54 x EF + 24.21; r = 0.86; S_x-bar = 4.84. LVCF -0.62 x DF + 65.3; r = -0.89, S_x-bar = 5.38. In conclusion, estimation of the left ventricular function and infarct size by the above defined CF is feasible, easy to perform and clinically meaningful. ^99mTc-MIBI gated myocardial imaging can provide data on myocardial perfusion and function, combining both aspects of nuclear cardiology in one procedure