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The maximum content of cation vacancies in perovskites determines the maximum adjustment to the physical properties. By using the classical criterion of the tolerance factor, we put forward a new method to obtain the maximum content of cation vacancies in perovskites. The effective ionic radius was calculated using the weighted average method, and the limit of tolerance factors was used to determine the maximum value of the cation vacancies. The calculated results of the La1-xMnO3 and La0.75Sr0.25Mn1-yO3 materials coincide with experimental results. For application, [(A1)1-x(A2)x]1-z1(B1B2)X3 or [(A1)1-x(A2)x](B1B2)1-z2X3 (X = O, F, Cl, Br, I) inorganic and hybrid organic-inorganic perovskite materials with vacancies at the A or B sites were predicted successfully, which provides a new method to improve the physical properties of perovskite materials.

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BACKGROUND: The role that probiotics play in relieving irritable bowel syndrome (IBS) has been demonstrated; however, the mechanism by which IBS is affected remains unclear. In this study, serotonin transporter (SERT) mRNA and serotonin transporter protein (SERT-P) levels in HT-29, Caco-2 cells, and mice intestinal tissues were examined after treatment with Lactobacillus rhamnosus GG supernatant (LGG-s). METHODS: HT-29 and Caco-2 cells were treated with different concentrations of LGG-s for 12 and 24 h and C57BL/6 mice received supplements of different concentrations for 4 weeks. SERT mRNA and SERT-P levels were detected by real-time PCR and Western blotting. KEY RESULTS: SERT mRNA and SERT-P levels in HT-29 and Caco-2 cells were higher than those in the control 24 h after treatment. Undiluted LGG-s upregulated SERT mRNA levels by 9.4-fold in the first week, which dropped in the second week. The double-diluted LGG-s upregulated SERT mRNA by 2.07-fold in the first week; levels dropped to 1.75-fold within the second week and under base expression levels by the third week, while they again climbed to 1.56-fold in the fourth week. The triple-diluted LGG-s could not upregulate SERT mRNA expression until the end of the fourth week. The SERT-P levels in the double-diluted LGG-s group were higher than that in the control but fluctuated with time. SERT-P levels in the triple-diluted LGG-s were higher than that in the control in the last 2 weeks and increased with time. CONCLUSIONS & INFERENCES: LGG-s can upregulate SERT mRNA and SERT-P levels in intestinal epithelial cells and mice intestinal tissues.

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The areas in China with climates suitable for the potential distribution of the pest species red turpentine beetle (RTB) Dendroctonus valens LeConte (Coleoptera: Scolytidae) were predicted by CLIMEX based on historical climate data and future climate data with warming estimated. The model used a historical climate data set (1971-2000) and a simulated climate data set (2010-2039) provided by the Tyndall Centre for Climate Change (TYN SC 2.0). Based on the historical climate data, a wide area was available in China with a suitable climate for the beetle in which every province might contain suitable habitats for this pest, particularly all of the southern provinces. The northern limit of the distribution of the beetle was predicted to reach Yakeshi and Elunchun in Inner Mongolia, and the western boundary would reach to Keerkezi in Xinjiang Province. Based on a global-warming scenario, the area with a potential climate suited to RTB in the next 30 years (2010-2039) may extend further to the northeast. The northern limit of the distribution could reach most parts of south Heilongjiang Province, whereas the western limit would remain unchanged. Combined with the tendency for RTB to spread, the variation in suitable habitats within the scenario of extreme climate warming and the multiple geographical elements of China led us to assume that, within the next 30 years, RTB would spread towards the northeast, northwest, and central regions of China and could be a potentially serious problem for the forests of China.

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Three techniques that use distal arteries for microvascular reconstruction in forearm and hand surgery are described: (1) distal based supply from the deep branch of the radial artery, (2) proximal reversal of the radial artery, and (3) distal based supply from the ulnar artery. Nine cases are described to illustrate the use of these techniques: three vascularized bone grafts, three toe-to-hand transfers, one free cutaneous flap, one brachial artery reconstruction, and one replantation of an amputated palm. The technique offers a number of advantages: (1) it eliminates the need for vein grafts, (2) it requires only a single arterial microvascular anastomosis, (3) it minimizes microvascular size discrepancies, (4) the distal artery can be prepared in the same operative field as the rest of the reconstruction, and (5) the technique enables an undamaged artery to be brought into a zone of trauma and used as a recipient vessel. The technique has the disadvantage that it sacrifices part of the collateral circulation to the hand and it is therefore important to check the blood supply to the hand preoperatively.

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545 cases of esophageal carcinoma were confirmed histologically and by esophagoscopic biopsy between Jan. 1982 and May 1990. Primary small cell carcinoma was identified in 19 cases. Of 11 patients confirmed operatively, 5 had oat cell carcinoma, 4 combined oat cell carcinoma and 2 intermediate cell carcinoma. The mean overall survival period was 13.9 months. The longest survival period was 27 months. The prognosis of primary small cell carcinoma was poorer than that of squamous carcinoma of the esophagus because of its propensity of spread and metastasis. Once the diagnosis of small cell carcinoma was established, surgery was undertaken as early as possible. For patients who had lymph node metastasis at the time of diagnosis, we recommended surgical treatment plus systemic chemotherapy after operation. To increase the resection rate, it is important to do chest CT scan, bronchiofiberscopy and B-type ultrasonography before operation.

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