The control of nanofiber orientation in nanofibrous tubular scaffolds can benefit the cell responses along specific directions. For small diameter tubular scaffolds, however, it becomes difficult to engineer nanofiber orientation. This paper reports a novel electrospinning technique for the fabrication of 3-D nanofibrous tubular scaffolds with controllable nanofiber orientations. Synthetic absorbable poly-ε-caprolactone (PCL) was used as the model biomaterial to demonstrate this new electrospinning technique. Electrospun 3-D PCL nanofibrous tubular scaffolds of 4.5 mm in diameter with different nanofiber orientations (viz. circumferential, axial, and combinations of circumferential and axial directions) were successfully fabricated. The degree of nanofiber alignment in the electrospun 3-D tubular scaffolds was quantified by using the fast Fourier transform (FFT) analysis. The results indicated that excellent circumferential nanofiber alignment could be achieved in the 3-D nanofibrous PCL tubular scaffolds. The nanofibrous tubular scaffolds with oriented nanofibers had not only directional mechanical property but also could facilitate the orientation of the endothelial cell attachment on the fibers. Multiple layers of aligned nanofibers in different orientations can produce 3-D nanofibrous tubular scaffolds of different macroscopic properties.

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Purpose Building is one of the main factors of energy use and greenhouse gas emissions. Reducing energy consumption and carbon dioxide (CO 2 ) emission from building is urgent for environmental protection and sustainable development. The objective of this study is to develop a life cycle assessment (LCA) model for an office building in China to assess its energy consumption and CO 2 emission, determine the whole life cycle phases, and the significant environmental aspects that contribute most to the impact. Methods A process-based LCA has been used to identify and quantify the energy consumption and CO 2 emission of the office building. The LCA is conducted in accordance with the Environmental Protection Agency, The Society of Environmental Toxicology and Chemistry, and the International Organization for Standardization standards for life cycle assessments. The entire life cycle including building materials production, construction, operation, and demolition of the building is studied. A service life of 50 years is assumed and the major construction materials such as concrete, cement, brick, steel, timber, glass, and plastic are selected for the building. Results and discussionThe results show that building operation uses the largest share of energy and contributes most to CO 2 emission. The cooling and heating system in building operation strongly influence the energy consumption and CO 2 emission of the building. In addition, the large quantity use of concrete and steel in materials production, and the treatment of end-of-life building materials are also the important aspects impacting the environmental performance of the building. Based on the results of the study, some environmental improvements aiming at reducing energy consumption and CO 2 emission throughout the life cycle of the building are provided.Conclusions This study provides an LCA of the energy consumption and CO 2 emission of a typical office building in China. It determines the whole life cycle phases that contribute most to the impact and defines the significant environmental aspects of the building. This study also shows the importance of using a life cycle perspective when evaluating energy consumption and CO 2 emission of building and also lays the groundwork for LCA studying of other office buildings in China.

The morbidity and mortality of patients with ischemic cardiomyopathy resulted from ischemia/reperfusion injury are very high. The present study investigates whether our previously synthesized water-soluble phosphate prodrug of acacetin was cardioprotective against ischemia/reperfusion injury in an in vivo rat model. We found that intravenous administration of acacetin prodrug (10 mg/kg) decreased the ventricular arrhythmia score and duration, reduced ventricular fibrillation and infarct size, and improved the impaired heart function induced by myocardial ischemia/reperfusion injury in anesthetized rats. The cardioprotective effects were further confirmed with the parent compound acacetin in an ex vivo rat regional ischemia/reperfusion heart model. Molecular mechanism analysis revealed that acacetin prevented the ischemia/reperfusion-induced reduction of the anti-oxidative proteins SOD-2 and thioredoxin, suppressed the release of inflammation cytokines TLR4, IL-6 and TNFα, and decreased myocyte apoptosis induced by ischemia/reperfusion. Our results demonstrate the novel evidence that acacetin prodrug confer significant in vivo cardioprotective effect against ischemia/reperfusion injury by preventing the reduction of endogenous anti-oxidants and the release of inflammatory cytokines, thereby inhibiting cardiomyocytes apoptosis, which suggests that the water-soluble acacetin prodrug is likely useful in the future as a new drug candidate for treating patients with acute coronary syndrome.

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