Performance indicators for energy efficiency retrofitting decision-making in residential buildings

The ‘‘energy performance of an existing building’’ is the amount of energy actually consumed to meet the different needs associated with standardized use of the building’ and is reflected in one or more numeric indicators known as Building Energy Performance Indicators or EnPIs that are distributed amongst 6 main factors influencing energy consumption; climate, building envelop, building services and energy systems, building operation and maintenance, occupants’ activities and behaviour, and indoor environmental quality. Any improvement made to either the existing structure, physical and operational upgrade of a building’s systems which enhance the energy performance is considered as an energy efficiency retrofit. The main objective of this paper is to support the implementation of residential energy retrofits through building of expert knowledge consensus on EnPIs for energy retrofit planning. The primary outcome of the research is a Comprehensive Index of EnPIs based on quantitative information knowledge to assist architects, building engineers, and energy analysts in providing retrofitting interventions as per in urban clusters rather than implementing generic solutions that try to fit all building types. The research methodology consisted of literature review which identified 37 EnPIs for residential buildings, followed by ranking questionnaire survey by experts in built-environment to arrive at weighted-average of all indicators. A total of 280-experts were requested for survey globally, and 107 completed responses received, i.e research had 37.5% response rate

The role of the secretin/secretin receptor axis in inflammatory cholangiocyte communication via extracellular vesicles

Abstract Small and large intrahepatic bile ducts consist of small and large cholangiocytes, respectively, and these cholangiocytes have different morphology and functions. The gastrointestinal peptide hormone, secretin (SCT) that binds to secretin receptor (SR), is a key mediator in cholangiocyte pathophysiology. Extracellular vesicles (EVs) are membrane-bound vesicles and cell-cell EV communication is recognized as an important factor in liver pathology, although EV communication between cholangiocytes is not identified to date. Cholangiocytes secrete proinflammatory cytokines during bacterial infection leading to biliary inflammation and hyperplasia. We demonstrate that cholangiocytes stimulated with lipopolysaccharide (LPS), which is a membrane component of gram-negative bacteria, secrete more EVs than cholangiocytes incubated with vehicle. These LPS-derived EVs induce inflammatory responses in other cholangiocytes including elevated cytokine production and cell proliferation. Large but not small cholangiocytes show inflammatory responses against large but not small cholangiocyte-derived EVs. Large cholangiocytes with knocked down either SCT or SR by short hairpin RNAs show reduced EV secretion during LPS stimulation, and EVs isolated from SCT or SR knocked down cholangiocytes fail to induce inflammatory reactions in control large cholangiocytes. This study identifies cholangiocyte EV communication during LPS stimulation, and demonstrates that the SCT/SR axis may be important for this event