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Using the definitions of potential functions and ordinal potential functions of strategic form games, we characterize two classes of potential games and give the solving method of the equilibria of finite potential games by testing and verifying potential games. The main contribution is proving that public goods games and social coordination games based on location strategic interaction with an exogenous network are potential games, and giving the equilibria by the method of solving potential games and ordinal potential games.

To determine the role of diffusion tensor imaging (DTI) metrics as biomarkers for the therapeutic effects of mesenchymal stem cells (MSCs) in acute peripheral nerve injury.Forty-four adult rats received subepineurial microinjection of MSCs (n = 22) or phosphate buffered saline (PBS, n = 22) 1 week after the sciatic nerve trunk crush injury. Sequential fat-suppressed T2-weighted imaging, T2 measurement, DTI and sciatic nerve functional assessment were performed at a 3.0 Tesla MR unit over an 8-week follow-up, with histological assessments performed at regular intervals. The sciatic nerve function index, T2 value, and DTI metrics, including fractional anisotropy (FA), axial diffusivity, radial diffusivity (RD), and mean diffusivity values of the distal stumps of crushed nerves were measured and compared between the two groups.Nerves treated with MSCs showed better functional recovery and exhibited more pronounced nerve regeneration compared with nerves treated with PBS. T2 values in nerves treated with MSCs or PBS showed a similar change pattern (P = 0.174), while FA and RD values in nerves treated with MSCs showed more rapid return (one week earlier) to baseline level than nerves treated with PBS (P = 0.045; 0.035). Nerves treated with MSCs had higher FA and lower RD values than nerves treated with PBS during the period from 2 to 3 weeks after surgery (P ≤ 0.0001, 0.004; P = 0.004, 0.006).FA and RD values derived from DTI might be used as sensitive biomarkers for detecting the therapeutic effect of stem cells in acute peripheral nerve crush injuries.2 J. Magn. Reson. Imaging 2017;45:855-862.

It is generally expected that inner-welded longitudinal stiffeners can be used to improve the structural performance of thin-walled hollow steel structural stub columns filled with concrete. Thirty-six specimens, including 30 stiffened stub columns and six unstiffened ones, were tested to investigate the improvement of ductile behaviour of such stiffened composite stub columns with various methods. The involved methods include increasing stiffener height, increasing stiffener number on each tube face, using saw-shaped stiffeners, welding binding or anchor bars on stiffeners, and adding steel fibres to concrete. It has been found that adding steel fibres to concrete is the most effective method in enhancing the ductility capacity, while the construction cost and difficulty will not be increased significantly.

An experimental study on the structural behaviour of concrete-filled stiffened thin-walled steel tubular columns is presented in this paper. The stiffening was achieved by welding longitudinal stiffeners on the inner surfaces of the steel tubes. Companion tests were also undertaken on 12 unstiffened concrete-filled steel tubular (CFST) columns, with or without steel fibres in the infill concrete. The test results showed that the local buckling of the tubes was effectively delayed by the stiffeners. The plate buckling initially occurred when the maximum load had almost reached for stiffened specimens, thus they had higher serviceability benefits compared to those of unstiffened ones. Some of the existing design codes were used to predict the load-carrying capacities of the tested composite columns.

Friedel–Crafts alkylation of 1,3-dimethoxybenzene with O-acetyldihydroqinghaosu gave a pair of 11-epimers of 12-(2,4-dimethoxyphenyl)deoxoqinghaosu 2 and 2′. The antimalarial activity of 11β-epimer 2 was comparable with that of artemether. Compound 2 reacted smoothly with ferrous ions or L-cysteine and catalytic amounts of ferrous ions to give a series of products derived from the previously postulated C-centered free radical, in particular the primary C-centered free radical. However, 11α-epimer 2′ was almost inert to ferrous ions and also showed low antimalarial activity. The identification of free radical mediated products and the correlation between chemical reactivity and bio-activity once again provided evidence for the key role of primary carbon-centered free radicals in the antimalarial activity of the qinghaosu series of compounds.

Qinghaosu(artemisinin) is the antimalarial principle of the Chinese traditional herb qinghao (Artemisia annua L.). Now qinghaosu and its derivatives have distinguished themselaves as a new generation of antimalarial drugs, especially in the treatment of multidrug-resistant cases. Qinghaosu has a unique carbon framework containing a special endoperoxy dridge, which is entirely different from that of all previous antimalarial agents and hence makes a novel antimalarial mechanism possible. Up to now there is still no clear picture about this mechanism at the molecular lever. However, the ferric/ferrous ions that are abundant in the red cell in which the parasite lives, is likely the most important co-factor for the antimalarial process of qinghaosu (scheme 1).

A convenient methodology for attaching an acid-stable UV chromophore onto the qinghaosu (artemisinin) framework with readily available dihydroqinghaosu acetate as the starting material is presented. The resulting derivatives of deoxoqinghaosu may be used as a sensitive probe in the mechanistic and biological/pharmacological investigations. As the first application of the present methodology, naphth-2-ol is attached to qinghaosu nucleus through a carbon–carbon single bond by a boron trifluoride-catalyzed Friedel–Crafts alkylation. A previously undetected racemization at C-9 mediated by an enol ether under the reaction conditions (BF3·OEt2, CH2Cl2) that have been widely used for preparing C-10 derivatives of dihydroqinghaosu is observed. The knowledge gained from the present work may assist the rational design of new trioxane-type antimalarial agents.

The present study investigated bladder and urogenital fatty fascial compartment (UFFC) variations during bladder filling in an attempt to identify other possible causes of hernia repair-related bladder injury besides mesh migration. The study included 30 patients scheduled for abdominal computed tomography (CT) scan for nonhernia diseases. Sixty-four-slice CT scan was performed immediately after urination and no more than 30 minutes later. Three-dimensional images were constructed by two independent experienced readers. The empty bladder was triangular in shape, narrow in the front and broad in the rear. Its vertex deviated from midline of the abdominal wall in 11 cases (36.7%). With normal filling, it appeared as an irregular oval shape. Only two cases (6.7%) of empty bladder extended inside Hesselbach's triangle. However, this area was occupied to some extent in all cases during bladder filling ( P = 0.003). The UFFC formed a molar-like structure in cross-section. In three dimensions, it appeared as an inverted V-shaped structure from the front. In the lateral view it appeared as a spoon that contained the bladder. UFFC volume increased from 61.85 ± 6.23 to 139.23 ± 5.29 cm3with bladder filling ( P < 0.0001). The UFFC can be clearly identified by CT scanning or three-dimensional reconstruction. The considerable spatial variation of the UFFC and movement and deformation of the mesh within this area may be related to bladder injury.

Friedel–Crafts alkylation of 1,3-dimethoxybenzene with O-acetyldihydroqinghaosu gave a pair of 11-epimers of 12-(2,4-dimethoxyphenyl)deoxoqinghaosu 2 and 2′. The antimalarial activity of 11β-epimer 2 was comparable with that of artemether. Compound 2 reacted smoothly with ferrous ions or L-cysteine and catalytic amounts of ferrous ions to give a series of products derived from the previously postulated C-centered free radical, in particular the primary C-centered free radical. However, 11α-epimer 2′ was almost inert to ferrous ions and also showed low antimalarial activity. The identification of free radical mediated products and the correlation between chemical reactivity and bio-activity once again provided evidence for the key role of primary carbon-centered free radicals in the antimalarial activity of the qinghaosu series of compounds.

Antimalarial compound qinghaosu (1) and its phenyl derivative 2 were reacted with reduced glutathione (GSH) and Fe(II/III) to give, besides other known degradation products, an interesting adduct from a primary C-centered free radical and GSH. Because GSH plays a very important role in the cell cycle, this finding may eventually lead to a new understanding of its mode of action.

Antimalarial compound qinghaosu (1) and its phenyl derivative 2 were reacted with reduced glutathione (GSH) and Fe(II/III) to give, besides other known degradation products, an interesting adduct from a primary C-centered free radical and GSH. Because GSH plays a very important role in the cell cycle, this finding may eventually lead to a new understanding of its mode of action.