•Operation optimization model of a Distributed Energy System (DES).•Multi-objective strategy to optimize energy cost and exergy efficiency.•Exergy analysis in building energy supply systems.
With the ...growing demand of energy on a worldwide scale, improving the efficiency of energy resource use has become one of the key challenges. Application of exergy principles in the context of building energy supply systems can achieve rational use of energy resources by taking into account the different quality levels of energy resources as well as those of building demands. This paper is on the operation optimization of a Distributed Energy System (DES). The model involves multiple energy devices that convert a set of primary energy carriers with different energy quality levels to meet given time-varying user demands at different energy quality levels. By promoting the usage of low-temperature energy sources to satisfy low-quality thermal energy demands, the waste of high-quality energy resources can be reduced, thereby improving the overall exergy efficiency. To consider the economic factor as well, a multi-objective linear programming problem is formulated. The Pareto frontier, including the best possible trade-offs between the economic and exergetic objectives, is obtained by minimizing a weighted sum of the total energy cost and total primary exergy input using branch-and-cut. The operation strategies of the DES under different weights for the two objectives are discussed. The operators of DESs can choose the operation strategy from the Pareto frontier based on costs, essential in the short run, and sustainability, crucial in the long run. The contribution of each energy device in reducing energy costs and the total exergy input is also analyzed. In addition, results show that the energy cost can be much reduced and the overall exergy efficiency can be significantly improved by the optimized operation of the DES as compared with the conventional energy supply system using the grid power only.
Eosinophils are important effector cells of the innate immune system. Eosinophilic infiltrative disorders of the gastrointestinal tract, though recognised for decades, have recently witnessed a ...resurgence of interest, particularly for oesophageal disease. A more comprehensive basis for eosinophilic infiltration and activation has identified interleukin 5 (IL5) as a key cytokine for the differentiation and proliferation of eosinophils, while eotaxins promote the recruitment of mature eosinophils to the gut. When activated, eosinophils release multiple cytotoxic agents and immunomodulatory cytokines, resulting in local inflammation and tissue damage. Although eosinophils normally convey a defence against unwanted interlopers such as parasites, in the absence of such inciting agents, their accumulation and activation can elicit the primary infiltrative disorders of the gut: eosinophilic oesophagitis, gastroenteritis and colitis. Diagnosis of these disorders is dependent on the clinical presentation, endoscopic findings (particularly for eosinophilic oesophagitis), and most importantly, histological confirmation. Dietary modifications and topical corticosteroids are first-line treatments for eosinophilic oesophagitis. Systemic corticosteroids are the mainstay of treatment for eosinophilic gastroenteritis; surgery may be required depending on the layer of mucosa involved. Eosinophilic colitis most often occurs in infants; removal of the causative allergen usually results in a complete response. Steroids may be required for older children/adolescents or adults. This review summarises current knowledge on the trafficking of eosinophils to the gastrointestinal tract and the clinical management of the primary disorders of eosinophilic oesophagitis, eosinophilic gastroenteritis and eosinophilic colitis.
Long noncoding RNAs (lncRNAs) have important roles in diverse biological processes. Our previous study has revealed that lncRNA-MALAT1 deregulation is implicated in the pathogenesis of ...diabetes-related microvascular disease, diabetic retinopathy (DR). However, the role of MALAT1 in retinal vasculature remodeling still remains elusive. Here we show that MALAT1 expression is significantly upregulated in the retinas of STZ-induced diabetic rats and db/db mice. MALAT1 knockdown could obviously ameliorate DR in vivo, as shown by pericyte loss, capillary degeneration, microvascular leakage, and retinal inflammation. Moreover, MALAT1 knockdown could regulate retinal endothelial cell proliferation, migration, and tube formation in vitro. The crosstalk between MALAT1 and p38 MAPK signaling pathway is involved in the regulation of endothelial cell function. MALAT1 upregulation represents a critical pathogenic mechanism for diabetes-induced microvascular dysfunction. Inhibition of MALAT1 may serve as a potential target for anti-angiogenic therapy for diabetes-related microvascular complications.
PDF
