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Occupant behavior has an important impact on building energy consumption, and the accuracy of an occupant behavior model directly affects the reliability of energy consumption simulation results. Ultra-low energy buildings are crucial to achieving building energy conservation and carbon dioxide reduction in China. In order to effectively promote the development of ultra-low energy buildings in Hot Summer and Cold Winter Climate Zones. where most residents adopt a “part-time, part-space” pattern of intermittent energy use behavior, and to solve the problem of poor indoor thermal environments and the high incremental cost of ultra-low energy, the study described in this paper takes Changsha as an example to carry out a multi-objective optimization study on ultra-low energy housing using a probabilistic behavioral model. On the basis of a probability model representing the residents’ actual behavior in Changsha, the optimization objective indicators, key variables and the technology benchmarks for ultra-low energy building were determined, then multi-objective optimization was carried out for a range of energy efficient technologies to obtain the Pareto optimal solutions. The results showed that the set of optimal solutions could reduce energy demand by 50.2 to 60.2% and reduce indoor thermal discomfort time by 3.52–11.09% compared with those of a reference base case, which just meets the requirements of the current design standard for energy efficient domestic buildings. An optimum solution for energy savings and indoor thermal comfort, along with economic costs, was identified, which can assist in decision-making by providing different preferences and provide useful reference for the design of ultra-low energy buildings in Hot Summer and Cold Winter Climate regions.

This paper presents an evaluation of the economic and technical feasibility of a renewable-led low carbon house in the UK. A holistic systems-based approach to achieve energy positive house has been taken. Long-term economic and technical feasibility analysis have been carried out based on a validated thermal and energy model of the house. The economic analysis employs the Return on Investment (ROI) method and considers changes to government financial support and technology progress over time. Results show that the extra investment on the house, compared with that for building a standard social house of similar size, can be paid back within the system lifespan under both the old Feed-in Tariff and its proposed replacement with reduced financial support. Variants examined in the technical feasibility analysis include housing type, orientation and location. Results show that the house can be replicated to achieve an energy positive performance for all variant combinations. Among the variants, location has the highest impact on building performance including annual electricity import, CO2 emission and electricity self-sufficient ratio, with South UK performing better than North UK. This implies that more efficient or advanced technologies would be needed to achieve similar building or system performance in areas of unfavourable climate. The outcome of the research has demonstrated the affordability of the energy positive house, and the technical feasibility of its replication with different housing types, orientations and locations in the UK. This study supports the wide scale replication of this affordable systems-based approach in domestic building design and construction when incorporating appropriate technologies.

Kashgar, located in China’s far west, has a typical hot-arid climate. There are a large number of low-rise high-density Islamic housing in Kashgar old City. The thermal comfort in these buildings has not yet been adequately researched. In order to obtain a comprehensive understanding about the real indoor thermal environment and the residents’ summer thermal comfort in Kashgar old City, a field investigation of 138 residential buildings was conducted in the summer time, including onsite environmental parameter measurements and simultaneous surveys using subjective thermal comfort questionnaires. Based on a statistical regression analysis of 182 valid questionnaires, a summer thermal comfort model was established. The results show that the measured summer neutral temperature of the local people is 23.4°C, and the upper limit of acceptable summer temperature for 80% of the residents is 26.9°C. The summer thermal tolerance of the residents in the Kashgar old City is lower than expected and also lower than that of the residents in rural Turpan with the same climate features. The survey also shows that the residents in the Kashgar old City have a habit of transfering living spaces over time, and the frequency of passive behaviours is higher than those of active behaviours. The above results are believed to be potentially valuable for the revision of energy conservation policies and the design practice of residential buildings in the hot-arid climate region of China, and also for areas under similar climate conditions in the world.

Background. Peroxisome proliferator activated receptor- gamma (PPAR-gamma), a nuclear hormone receptor, has been shown to be an important regulator of gene expression. PPAR-gamma agonists have been shown to have anti-cancer properties by ways of inducing expression of tumour suppressor genes. It has been indicated that this action of PPAR-gamma is manifested by forming a complex with the PPAR-gamma coactivators (PGC1 &2) and in association with other transcription factors such as SRC-1 and CREB binding proteins. Both PPAR-gamma and PGC-1 have been shown to be aberrantly expressed in human cancer including human breast cancer (1). PPAR-gamma also plays a role in regulating angiogenesis and that PPAR-gamma agonists have been shown to have anti-angiogenic functions. In the present study, we investigated the role of PGC-1 in PPAR-gamma mediated actions on vascular endothelial cells. Materials and methods. Mammalian expression systems for human full length PGC-1 ereonstructed. Anti-PGC-1 transgenes were constructed again using human mammalian expression vector in order to knock down PGC-1 transcript from the cells. Human vascular endothelial cell, HECV, was used in the study. Cell functions linked to angiogenesis including cell adhesion and cellular migration was evaluated using the electric cell impedance sensing method. PPAR-gamma agonists and antagonists were used in the cell models during the analyses. Results. HECV cells weakly expressed PGC-1 and PPAR-gamma. Using the transgenes created, sublines over-expressing PGC1 (HECVPGC1exp) or with PGC-1 expression knockdown (HECVPGC1KD) were established. Loss of PGC1 showed marked increase in both adhesion and cellular migration, opposite was true forHECVPGC1exp cells. PPAR-gamma agonist, pioglitizone and ciglitizone, reduced the adhesion of control cells. In contrast, PPAR-gamma antagonist SR202 exhibited a concentration dependent stimulation of both adhesion and migration of the control cells. Knocking down PGC1 in endothelial cells rendered cells lost response to SR202. Conclusions. PGC-1 is essential in during the modulation of endothelial cells by PPAR-gamma. Together with the aberrant expression of both PPAR-gamma and PGC-1 in breast cancer, it is concluded that PGC-1 is a central player in PPAR-gamma mediated action in both cancer cells and angiogenesis. 1. Jiang WG, Douglas-Jones A, Mansel RE. Expression of peroxisome-proliferator activated receptor-gamma (PPARgamma) and the PPARgamma co-activator, PGC-1, in human breast cancer correlates with clinical outcomes. Int J Cancer. 2003, 106(5):752–757. Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-05-02.