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To explore the therapeutic effect of metformin combined with single high-dose radiotherapy in mice with non-small cell lung cancer and the mechanism involved. In vitro cell test: the cytotoxicity of metformin under different oxygen and glucose contents was evaluated using cell survival curves. In vivo xenograft tumor test: NSCLC-A549 cells were injected into mice, which were then divided into the following five groups: control group, metformin group, single high-dose radiotherapy group, metformin 1 h before radiotherapy group, and metformin 24 h after radiotherapy group. Growth of the tumor was evaluated in each group, and the blood flow and histology of the tumor tissues were analyzed. According to the in vitro test results, metformin was the most cytotoxic under hypoxic and low-glucose conditions. The in vivo results showed that the tumor volume was the smallest in the mouse groups administered metformin 1 h before high-dose radiotherapy and 24 h after radiotherapy ((0.47±0.12) cm3 and (0.49±0.21) cm3, respectively). Blood flow analysis showed that single high-dose radiotherapy destroyed the micro-vessels of tumor tissue and reduced the perfusion of oxygen and glucose. Histological analysis revealed that cells in hypoxic and hypoglycemic area of the tumor tissue center were preferentially killed by metformin, whereas there were viable cells in the surrounding well perfused areas. Metformin combined with single high-dose radiotherapy enhanced the toxicity by changing tumor cell metabolism. These results provide theoretical and data support for the future use of metformin combined with stereotactic body radiotherapy.

For a three-dimensional magnetohydrodynamics solar wind model, it is necessary to carry out assessment studies to reveal its ability and limitation. In this paper, the ambient solar wind results of year 2008 generated by the CESE-HLLD 3D MHD model are compared with multipoint in-situ measurements during the late declining phase of solar cycle 23. The near-ecliptic results are assessed both quantitatively and qualitatively by comparing with in-situ data obtained at the L1 point and by the twin STEREO spacecraft. The assessment reveals the model’s ability in reproducing the time series and statistical characteristics of solar wind parameters, and in catching the change of interplanetary magnetic field polarity and the occurrence of the stream interaction regions. We find that the two-stream structure observed near the ecliptic plane is reproduced, but the differences among observations at L1 and the twin STEREO spacecraft are not caught by the model. The latitudinal variation of the results is assessed by comparing with the Ulysses observation. The characters of variation in different latitudinal ranges are duplicated by the model, but biases of the results are seen, and the boundary layers between fast and slow solar wind are sometimes thicker than observation.

Aimed to be ready for the transition from research to operation, we have developed a solar wind model by coupling a data-driven empirical coronal model with a magnetohydrodynamics heliospheric model. We performed a data-driven simulation of the solar wind for a two-year period during the declining and minimum phases of solar cycle 23. Comparisons with OMNI and Ulysses spacecraft data show that the model can reproduce the large-scale variations of the solar wind plasma parameters. The evolution of geocentric solar magnetospheric (GSM) Bx and Bz components are also reasonably duplicated by the model in terms of polarity and strength. Apparent signatures of the Russell–McPherron (R-M) effect are found from both observed data and simulated results, indicating that during the investigated interval the R-M effect is the dominant mechanism that controls the large-scale evolution of the north–south component of the interplanetary magnetic field in the GSM frame. The results demonstrate that the established model can provide valuable space weather information about the solar wind. [ABSTRACT FROM AUTHOR]

The aim of this study was to study the role of Th1/Th2 cell‐associated chemokines in the formation of hypertrophic scars in rabbit ears. Twenty‐six New Zealand white rabbits were used to establish the hypertrophic scar model of rabbit ear and the normal scar model of rabbit's back. Two rabbits were sacrificed on days 0 and 21, 28, 35, 42, 49, 56, and 63 after operation. The specimens were stained with haematoxylin‐eosin (HE). Scar elevation index (SEI) was used to detect the expression of 10 chemokines related to Th1/Th2 cells in both scar formation expressions. Real‐time polymerase chain reaction (PCR) results showed that two chemokines (CXCL10, CXCL12) were highly expressed during the formation of normal scar, and there was almost no expression during the formation of hypertrophic scar (*P < 0.05). The chemokines (CCL2, CCL3, CCL4, CCL5, CCL7, CCL13, CX3CL1) were almost non‐expressed in the formation of normal scars but were expressed for a long time in the formation of hypertrophic scars. The four chemokines, CCL2, CCL4, CCL5, and CX3CL1, maintained a long‐term high expression level during the formation of hypertrophic scars (P < 0.01). There were also three chemokines (CCL14, CCL19, CCL21) that were almost undetectable in normal scarring, but there was transiently low‐level expression (P < 0.05) only during the peak proliferative phase in proliferative scarring. Th1/Th2 cell‐associated chemokines are different in the type, quantity and expression, and maintenance time of rabbit ear hypertrophic scars. [ABSTRACT FROM AUTHOR]

The ZrB2-SiC-graphite composite is one of the most promising ceramics, which show significant potential in manufacturing parts served in ultra-high temperature. Micro-electrical discharge machining (micro-EDM) is an effective method in machining this conductive hard ceramic. However, the recast layer characterized by craters and micro-cracks is formed on the machined surface, resulting in poor surface quality. In this paper, micro-EDM and micro-ultrasonic machining (micro-USM) combined milling is proposed for manufacturing 3D micro-cavities in the ZrB2-SiC-graphite composite. The micro-cavity is firstly machined by micro-EDM milling, followed by micro-USM finish milling to remove the recast layer in the same system without changing the micro-tool. The machining performances are investigated with consideration of the surface topography and finishing depth. It is found that the more recast layer is removed when a higher ultrasonic amplitude, larger abrasive grain size, and lower tool feedrate are employed. Based on the preliminary experiments, the proper machining parameters are obtained and applied to the fabrication of micro-cavities. The machining results show that the surface quality is improved with the low surface roughness and absence of defect layer. Meanwhile, the high machining accuracy in the depth direction and processing efficiency are achieved. It is verified that the micro-EDM and micro-USM combined milling process is feasible for fabricating 3D micro-cavities in the ZrB2-SiC-graphite composite. [ABSTRACT FROM AUTHOR]