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Cyclosporin A is a calcineurin inhibitor which has a narrow therapeutic window and high interindividual variability. Various population pharmacokinetic models have been reported; however, professional software and technical personnel were needed and the variables of the models were limited. Therefore, the aim of this study was to establish a model based on machine learning to predict CsA trough concentrations in Chinese allo-HSCT patients. A total of 7874 cases of CsA therapeutic drug monitoring data from 2069 allo-HSCT patients were retrospectively included. Sequential forward selection was used to select variable subsets, and eight different algorithms were applied to establish the prediction model. XGBoost exhibited the highest prediction ability. Except for the variables that were identified by previous studies, some rarely reported variables were found, such as norethindrone, WBC, PAB, and hCRP. The prediction accuracy within ±30% of the actual trough concentration was above 0.80, and the predictive ability of the models was demonstrated to be effective in external validation. In this study, models based on machine learning technology were established to predict CsA levels 3–4 days in advance during the early inpatient phase after HSCT. A new perspective for CsA clinical application is provided. [ABSTRACT FROM AUTHOR]

Lead-free piezoceramics (K0.5N0.5)NbO3-xwt% Bi4Ti3O12were fabricated, and effects of Bi4Ti3O12on the properties of (K0.5N0.5)NbO3ceramics were investigated. The results show that the orthorhombic and tetragonal transition temperature of the ceramics shifts toward room temperature and a small amount of Bi4Ti3O12cannot influence the symmetry of (K0.5N0.5)NbO3ceramics but improve their electrical properties. Optimum piezoelectric properties are owned by (K0.5N0.5)NbO3–0.50 wt% Bi4Ti3O12:d33= 135 pC/N,kp= 36.4%, andTC= 406°C, whereas the relatively superb ferroelectric properties are obtained by (K0.5N0.5)NbO3–0.75 wt% Bi4Ti3O12:Pr= 27.2 μC/cm2,Ec= 7.6 kV/cm, andTC= 398°C. [ABSTRACT FROM AUTHOR]

(1−x)(K0.5Na0.5)NbO3-xBi0.5(Na0.9K0.1)0.5TiO3((1−x)KNN-xBNKT) lead-free ceramics were prepared by the conventional solid state reaction technique, and the effects of BNKT on the phase structure, microstructure, ferroelectric and piezoelectric properties of (1−x)KNN-xBNKT ceramics were investigated. The addition of BNKT strongly affects the microstructure of these ceramics, and changes the crystalline structure of these ceramics from an orthorhombic phase withx< 0.02 to a tetragonal phase withx≥ 0.03 at room temperature. A coexistence of orthorhombic and tetragonal phases was identified in the range of 0.02 ≤x< 0.03. 0.975KNN-0.025BNKT ceramics show the optimum piezoelectric properties ofd33∼170 pC/N andkp∼0.38. [ABSTRACT FROM AUTHOR]

0.975(K0.5Na0.5)NbO3–0.025Bi0.5(Na0.9K0.1)0.5TiO3(0.975KNN-0.025BNKT) lead-free piezoelectric ceramics were prepared, and the effects of sintering temperature on the microstructure, density, and piezoelectric properties of the ceramics were investigated. It was found that sintering densification of the ceramics occurs within a narrow temperature range, when the sintering temperature slightly deviates from optimal one the density of the ceramics decreases apparently, and the deviation would lead to uneven distribution of Bi and Ti, which will also affect the microstructure and the piezoelectric properties of the ceramics. It is concluded that the sintering temperature is a very critical factor for the KNN-based ceramics. [ABSTRACT FROM AUTHOR]

(K0.5Na0.5)(Nb0.92Sb0.03Ta0.05)O3-xmol%CuO (KNNST-xCu) piezoelectric ceramics were prepared by traditional technique. The phase structure, surface morphologies, piezoelectric constantd33, electromechanical coupling factorkp, mechanical quality factorQmand the dielectric loss tanδof the specimen were investigated. CuO addition “hardened” the KNNST ceramics and significantly enhanced the mechanical quality factorQm. The results show that the ceramics doped with 2.0–3.0 mol% CuO exhibit a highQmof 1134 and a low tanδof 0.8%, while the other piezoelectric properties remain reasonably high:d33= 130 pC/N andkp= 44.1%. [ABSTRACT FROM AUTHOR]

Dense Na0.5Bi2.5Nb2O9(NBN) based high temperature piezoelectric ceramics were prepared by solid-state reaction method. The effects of Ca2+and/or Sb5+in NBN pseudo-perovskite structure A and/or B site were studied. The introduction of Sb5+into B site decreases Curie temperatureTcand piezoelectric constantd33, while Ca2+into A site increasesTcandd33. Within the selected compositional range, the incorporation of Ca2+and Sb5+into A, B site, respectively, increasedd33compared to NBN. The optimum content of Ca2+and Sb5+are 3.0 mol%, 1.0 mol%, respectively, of which, the piezoelectric constantd33is about 18.1 pC/N,Tcis about 790°C. [ABSTRACT FROM AUTHOR]

A low-temperature sintering method of (K0.48Na0.52)NbO3ceramics was developed by co-doping of Co2O3and ZnO, and the sintering behavior and electrical properties of the ceramics were studied. The results show that the addition of Co2O3and ZnO is very effective to improve the density and sinterability, and the ceramics could be well sintered at 950°C as compared with pure KNN ceramics sintered at 1120°C. The excellent properties ofρ= 4.36 g/cm3,d33= 108 pC/N,kp= 33.3 %,Qm= 177,Pr= 22 μC/cm2, andEc= 13.7 kV/cm were obtained in (K0.48Na0.52)NbO3-0.1mol%Co2O3-1mol%ZnO ceramic sintered at 950°C. [ABSTRACT FROM AUTHOR]

0.94Bi0.5Na0.5TiO3-0.06BaTiO3 (BNT-06) lead-free piezoelectric ceramic has been prepared by using a novel low-temperature solid-state synthesis method. The relationship between the calcine conditions and the electrical properties of the ceramics was systematically studied. The results show that a small amount of the activated assistant additives in the raw materials by using the novel low-temperature solid-state synthesis method decreases the calcine temperature of the BNT-06 powder from 900°C to 600°C. The BNT-06 ceramics prepared by using this powder presents good properties with ρ = 5.86 g/cm3, d33 = 122 pC/N, kp = 0.24, Qm = 109, TC = 271.2°C, εr = 1656, tan δ = 0.05, Pr = 32.6 μC/cm2, and Ec = 32.1 kV/cm respectively, which is comparable to that of the ceramics prepared by using ordinary solid-state method. [ABSTRACT FROM AUTHOR]

(K, Na, Li)Nb0.95Sb0.05O3 lead-free piezoelectric ceramics were prepared by conventional mixed oxide method. The effect of Li substitution for the K and/or Na-sites of the (K0.5Na0.5)Nb0.95Sb0.05O3 ceramics on the piezoelectric and ferroelectric properties were investigated. The results show that the 1-3 mol% Li-substituted samples possess lower dielectric loss (tan δ), larger planar electromechanical coupling factor (kp) and remnant polarization, while the ceramics with high concentration of Li (6-8 mol%) possess higher piezoelectric constant, dielectric constant, and coercive field. In particular, the (K0.475Li0.025Na0.5)Nb0.95Sb0.05O3 ceramics possess a high kp of 49% and a low tan δ of 0.019. [ABSTRACT FROM AUTHOR]

ZnS and Co2+: ZnS nanocrystals were prepared in aqueous solution by one-pot method using thioglycolic acid as stabilizer. The nanocrystals were characterized by X-ray diffraction (XRD), FT-IR spectra and UV-Vis absorption spectra. The results show that both ZnS and Co2+: ZnS nanocrystals possess zinc-blende strcture. The host nanocrystals size dependence of Co2+ doping was investigated experimentally. Well match in ionic radii of Co (0.74 Å) and Zn (0.74 Å) should be responsible for the easier substitutionally doping growth than that of other Co2+ doped chalcogenide nanocrystals. [ABSTRACT FROM AUTHOR]

New BNT-based lead-free piezoelectric ceramics, Bi0.5(Na1 - x - yKxLiy)0.5TiO3 (BNKLT-x/y), were prepared. The doping of the ceramics with various oxides was studied. BNKLT-x/y ceramics show excellent piezoelectric and ferroelectric properties: d33 = 231 pC/N, kP = 41.0%, kt = 50.5%, Pr = 40.2 C/cm2, and Ec = 2.47 kV/mm, respectively. The dependence of P-E loops on temperature reveals that the optimum depolarization temperature Td is 195°C. The buzzers and filters were fabricated by using BNKLT-x/y ceramics. The ceramics could be one kind of the substitution materials for lead-based piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

New lead-free piezoelectric ceramics, [Bi0.5(Na1 - x - y - zKxLiyAgz)0.5]TiO3, were prepared by conventional sintering technique and their piezoelectric and dielectric properties were studied. X-ray diffraction reveals that all ceramics investigated have pure perovskite phase. The ceramics provides good piezoelectric properties: piezoelectric constant d33 = 215.5 pC/N, planar electromechanical coupling factor kP = 39.3% and thick electromechanical coupling factor kt = 50.6%, respectively. The dependence of dielectric properties on temperature indicates that a diffusing peak of dielectric constant occurs at about 200°C. This kind of ceramics may be used in practical devices. [ABSTRACT FROM AUTHOR]