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An external fixator is a promising medical device that could provide optimum stability and reduce the rate of complications in treating bone fracture during intervention period. It is noted that the biomechanics behaviour of device can be altered by introducing more features such as material suitability and additional components. Therefore, this study was conducted via finite element method to investigate the effects of additional hollow cylinder coated with external fixator screws in treating Type III pilon fracture. Finite element models which have been validated with experimental data were used to simulate stresses at the pin-bone interface and relative micromovement at interfragmentary fractures during swing (70 N load) and stance phases (350 N load). All bones and external fixators were assigned with isotropic material properties while the cartilages were simulated with hyper-elastic. For the hollow cylinder, polyethylene was assigned due to its properties which are equivalent to the bone. From the results, it is found that stresses at the pin-bone interface for the coated screws were reduced to 54% as compared to the conventional fixator. For the micromovement, there was no difference between both models, whereby the value was 0.03 mm. The results supported previously published literature, in which high stresses are unavoidable at the interface, fortunately, those stresses did not exceed the ultimate strength of bone, which is safe for treating patients. In conclusion, if patients are allowed to bear weight bearing, the external fixator with coated screws is a more favourable option to be fixed into the bone to avoid complications at the interface.

The recent outbreak of coronavirus disease 2019 (COVID-19) by SARS-CoV-2 has led to uptodate 24.3 M cases and 0.8 M deaths. It is thus in urgent need to rationalize potential therapeutic targets against the progression of diseases. An effective, feasible way is to use the pre-existing ΔORF6 mutant of SARS-CoV as a surrogate for SARS-CoV-2, since both lack the moiety responsible for interferon antagonistic effects. By analyzing temporal profiles of upregulated genes in ΔORF6-infected Calu-3 cells, we prioritized 55 genes and 238 ligands to reposition currently available medications for COVID-19 therapy. Eight of them are already in clinical trials. Of particular importance is the emergence of immune checkpoint inhibitors targeting PD-L1 that have not been used in COVID-19 treatment. We also pinpointed 16 drug groups from the Anatomical Therapeutic Chemical classification system, with the potential to mitigate symptoms of SARS-CoV-2 infection and thus to be repositioned for COVID-19 therapy., Highlights • Rationalization of useful therapeutic targets against the COVID-19 is of urgent need. • Transcriptomic perturbation profiles of SARS-CoV ΔORF6 mutant revealing 55 genes and 238 ligands to reposition to COVID-19. • Immune checkpoint inhibitors targeting PD-L1 shows potential for COVID-19 treatment. • 16 Anatomical Therapeutic Chemical classes were valuable for further investigation to treat COVID-19.

Oxygen vacancies of metal oxides play a critical role in photocatalytic activity. In this work, a novel method involving the adjustment of pH and use of a surfactant is used to synthesize Sr2FeMoO6 having more oxygen vacancies. The synthesized photocatalyst (Sr2FeMoO6) is used to study the relationship between oxygen vacancies and photodegradation of methyl blue (MB) solution. Sr2FeMoO6 samples were prepared using sol-gel (S1 sample), hydrothermal (S2 sample), and thermal decomposition of a metal-organic salt using organic solvent methods (S3 sample). The photocatalytic activities of synthesized samples fell in the descending order of: S3 > S1 > S2. Similarly, the surface oxygen vacancies of synthesized photocatalysts (S1, S2 and S3) were found to be in the descending order of: S3 > S1 > S2. Based upon the comparison and analysis of S1 and S4, the effect of pH value under similar synthesis conditions was studied. Furthermore, EDTA (surfactant) was used to synthesize Sr2FeMoO6 (herein, referred to as S5) having the same pH as that of S3. The comparison of S4 and S5 samples was used to probe the effect of Sr2FeMoO6 photocatalyst, synthesized using a surfactant-assisted route. Excellent photocatalytic activity was found for sample S5, where the pH of 8 was the optimum for sol-gel preparation method. The MB solution can be degraded completely (100%) in 35 min for S5 sample. The results indicate that the lattice oxygen vacancies can promote the harvesting of visible light and narrow the band gap, while the surface oxygen vacancies can increase the separation efficiency of charge-carriers. Beside their critical role in the evolution of photocatalytic oxygen, the surface oxygen vacancies also proved helpful in separating electrons and holes.

Bi 2 MoO 6 samples with different morphologies have been prepared using co-precipitation and hydrothermal methods. Octahedral-, spherical-, and plate-like particles have been obtained by changing some external factors including preparation methods, solvent types, and surfactants. Our results suggest that pure Bi 2 MoO 6 phase with nanoplate morphology are easily obtained via hydrothermal preparation method using ethylene glycol solvent. The photocatalytic and photoelectric properties of these Bi 2 MoO 6 samples have also been investigated in detail. Moreover, the photocatalytic activity is enhanced with addition of surfactants, such as Polyvinylpyrrolidone (PVP), Sodium dodecyl sulfate (SDS), and cetytrimethylammonium bromide (CTAB). The excellent photocatalytic activity is found for CTAB addition, which is nearly 100%. It may be ascribed to the specifically exposed facets structure, which is related to larger visible light absorption and improved separation of photogenerated charge carriers.

Eu3+ and Ba2+ co-doped Sr4V2O9 samples are prepared via a hydrothermal method and the structure, morphology, and photoluminescence properties are investigated. Sr4V2O9 is composed of disperse nano-rods. However, with Eu3+ and Ba2+ co-doping, nano-rods begin agglomerated and extend outward from the center to form a flower-like structure. Photoluminescence measurement indicates that Ba2+ dopants greatly enhance the emission intensity, for example, the enhanced emission intensity reaches for 234% when Ba2+ content is 5% for Sr4V2O9:Eu3+ (10%),Ba2+ (x%). However, with Ba2+ increasing further, the emission intensity decreases for Sr4V2O9:Eu3+ (10%),Ba2+ (x%) and Sr4V2O9:Eu3+(15%),Ba2+ (x%) samples, which is ascribed to the quenching behaviors. Further, CIE coordinates of (0.666, 0.333) for Sr4V2O9:Eu3+ (15%),Ba2+ (8%) sample, very similar to the (0.665, 0.334) coordinates for the commercial red phosphor Y2O3S:Eu3+, can be obtained.

The Y0.5−xGd0.35Eu0.15BixNbO4 (0 ≤ x ≤ 0.30) and Y0.35Gd0.35Eu0.15Bi0.15Nb1−yPyO4 (0 ≤ y ≤ 0.20) phosphors have been synthesized by the conventional solid-state reaction. For these Y0.5−xGd0.35Eu0.15BixNbO4 (0 ≤ x ≤ 0.30) samples, the emission increases and then decreases with increasing Bi content, and the maximum emission is achieved when x is 0.18. As for the Y0.35Gd0.35Eu0.15Bi0.15Nb1−yPyO4 (0 ≤ y ≤ 0.20) samples, the emission and excitation intensities are both varied with the P doping content. The strongest intensity is obtained in the case of y = 0.15. These results indicate that the Bi dopant acts as one sensitizer and enhances the photoluminescence intensity. The introduction of PO43− also plays an important role in the photoluminescence properties of the investigated samples. The relevant mechanism has been also presented.

The effects of Cr doping on Mn sites in the electron-doped manganites La0.9Te0.1MnO3 have been studied by preparing the series La0.9Te0.1Mn1−xCrxO3 ( 0.05 ≤ x ≤ 0.20 ). Upon Cr doping, both the Curie temperature T C and magnetization M are suppressed. The resistivity measurements indicate that there exists a weak metal–insulator (M–I) transition for the sample with x = 0.05 , with an increase in the doping level, the M–I transition disappears and the resistivity increases. Thermopower S ( T ) exhibits a maximum near T C for all samples. By fitting the S ( T ) and ρ ( T ) curves, it is found that the temperature dependences of both S ( T ) and ρ ( T ) in the high temperature paramagnetic (PM) region follow the small polaron conduction (SPC) mechanism for all samples. The fitting parameters obtained imply changes of both the average-hopping distance of the polarons and the polaron concentration with Cr doping in our studied samples. In the case of the thermal conductivity κ ( T ) , the variation of κ ( T ) is analyzed based on the combined effects due to the suppression of the local Mn3+O6 Jahn–Teller (JT) lattice distortion because of the substitution of Cr3+ for Mn3+ ions, which results in the increase in κ , and the introduction of the disorder due to Cr-doping, which contributes to the decrease in κ .

Magnetic and electronic transport properties of the electron-doped manganites La0.9−xAxTe0.1MnO3 (A = Y or Ho, 0.05 ⩽ x ⩽ 0.15 ) have been investigated by measurements of magnetization, resistivity and magnetoresistance. All samples undergo a paramagnetic (PM)–ferromagnetic (FM) phase transition at Curie temperature T C and T C shifts to lower temperature with increasing Y/Ho doping level. It is very interesting to find that the values of T C and M of the Ho composition are smaller than those of the Y composition for the same concentration, although Y and Ho ions have almost the same ionic radii. Electronic transport measurements indicate that the Ho-doped compound have higher resistivity than the Y-doped one for the same doping level. These observed results are discussed according to the antiferromagnetic (AFM) coupling of the Ho magnetic moment to that of Mn.

Systematical studies of resistivity ρ ( T ) , thermopower S ( T ) , and thermal conduction κ ( T ) have been performed on the electron-doped manganites La 0.9− x A x Te 0.1 MnO 3 (A = Y or Ho, 0.05 ⩽ x ⩽ 0.15 ). The Y005, Y010, Ho005 and Ho010 samples exhibit double insulator–metal (I–M) transitions in the ρ ( T ) curves, one is very close to its Curie temperature T C , the other is well below T C . However, the Y015 and Ho015 samples present insulating behaviors in the whole measured temperature. S shows positive sign for all samples with a peak near T C and a bump/peak in the ferromagnetic (FM) region. The ρ ( T ) and S ( T ) data above T C can be fitted well by the variable-range hopping (VRH) model. The small thermal conduction data suggests that there exists a large JT distortion in the studied samples. Moreover, comparing with the Y-doped compounds, the Ho-doped ones have smaller the thermal conduction value. This result is discussed as the existence of antiferromagnetic (AFM) coupling between Ho and Mn ions in the Ho-doping samples. On the one hand, the magnetic disorder enhancement due to the competition of ferromagnetic (FM) and AFM lower the thermal conductivity, on the other hand, the AFM coupling will reduce the phonon–phonon scattering.

The Young's modulus and the transport and magnetic properties of polycrystalline La0.5Ca0.5−xTexMnO3 ( x = 0 , 0.05, and 0.1) have been studied systematically. It was found that with increasing Te content, the resistivity decreases, the Curie temperature T C increases and the relative Young's modulus decreases. We suggest that Te doping destroys the charge ordering (CO) and induces the ferromagnetic (FM) metallic state accompanied by an evolution from the Q 3 -type distorting mode to Q 2 -type one. In addition, we found that the evolution from magnetic to electronic phase separation is close related to the rapid decrease in the ratio of two kinds of Jahn–Teller distortion modes Q 3 and Q 2 , i.e., Q 3 / Q 2 .

The changes of the Young's modulus E and the resistivity ρ under different dc currents for the electron-doped manganites Ca1−xLaxMnO3 ( x = 0.15 , 0.20, 0.25 and 0.30) (CLMO) are investigated by means of in-situ measuring method. For all samples, both values of the relative Young's modulus ΔE and the resistivity ρ are lowered with increasing current at low temperatures. The correlation of these changes in ΔE and ρ is discussed and the resistivity drop induced by the larger current is suggested to originate from the lattice variation. In addition, as the current increases from 10 to 40 mA, the variation of ΔE and ρ becomes smaller with decreasing doping level x, and it is ascribed to the decrease of the charge ordering (CO) component accompanying with the magnetic transition from CE-type to C-type antiferromagnetic (AFM) structure.

Conformationally restricted carbamate inhibitors, exo -2-norbornyl- N -butylcarbamate ( 1 ), endo -2-norbornyl- N -butylcarbamate ( 2 ), 1-adamantyl- N -butylcarbamate ( 3 ), and 2-adamantyl- N -butylcarbamate ( 4 ) as active site-directed irreversible inhibitors of horse serum butyrylcholinesterase are investigated for values of the dissociation constant ( K I ), the carbamylation constant (k 2 ), and the bimolecular rate constant (k i ). Compound 1 is the most potent inhibitor of the enzyme and the values of K I and k i are 20 nM and 1.1×10 5 M −1 sec −1 .