Urban energy system and climate indicators for urban energy planning

BACKGROUND AND OBJECTIVES: Cities are the main energy consumers; they can be a critical solution to threats to energy resources, the environment, and climate change. Knowing the effective indicators in urban planning and design in the energy field is one of the priorities of urban planners and designers. In this regard, Current research in the first step has tried to define a conceptual framework of urban system indicators influential to energy planning in cities.  And in the second step, since climatic characteristics could be as fundamental factors in urban energy planning, the relationship between climatic indicators and urban energy planning indicators has been identified.METHODS: This study is basic research in terms of purpose and presents a new conceptual framework for the urban energy system. It also aimed to analyses the relationship between the urban energy system indicators and local climate indicators. Its methodology is descriptive-analytical, conducted by library method and survey. Data analysis was done through a combination of quantitative and quantitative methods and descriptive statistical analysis. To do the survey questionnaire and interview experts in the energy field in different countries by using the Delphi method has been done.FINDINGS: The urban energy system conceptual framework was identified, and it has been divided into seven sub-systems (physical, land use, infrastructure, and transportation, movement/accessibility, cultural and technological), 15 components, and 61 indicators. Also, by analyzing the relationship between urban energy and climate indicators, “Air temperature” is the most related climate indicator from the experts’ view with 682 total scores, followed by “Solar radiation and sunny days”, “greenery” and “wind” indicators respectively with the sum points of 624, 596 and 594 scores in the seven defined urban energy system indicators.CONCLUSION: A theoretical framework of urban energy systems has been defined based on previous studies and experts' ideas in a comprehensive framework. And by analyzing the relationship between the defined urban energy system and climate indicators, the important indicators were recognized in each group. That could be academic knowledge and a practical source for future urban plans. For future studies, the institutional and economic dimensions of urban energy systems have to be conducted to complete the theoretical framework

Pathological structural conversion of α-synuclein at the mitochondria induces neuronal toxicity

Aggregation of alpha-synuclein (α-Syn) drives Parkinson’s disease (PD), although the initial stages of self-assembly and structural conversion have not been directly observed inside neurons. In this study, we tracked the intracellular conformational states of α-Syn using a single-molecule Förster resonance energy transfer (smFRET) biosensor, and we show here that α-Syn converts from a monomeric state into two distinct oligomeric states in neurons in a concentration-dependent and sequence-specific manner. Three-dimensional FRET-correlative light and electron microscopy (FRET-CLEM) revealed that intracellular seeding events occur preferentially on membrane surfaces, especially at mitochondrial membranes. The mitochondrial lipid cardiolipin triggers rapid oligomerization of A53T α-Syn, and cardiolipin is sequestered within aggregating lipid–protein complexes. Mitochondrial aggregates impair complex I activity and increase mitochondrial reactive oxygen species (ROS) generation, which accelerates the oligomerization of A53T α-Syn and causes permeabilization of mitochondrial membranes and cell death. These processes were also observed in induced pluripotent stem cell (iPSC)–derived neurons harboring A53T mutations from patients with PD. Our study highlights a mechanism of de novo α-Syn oligomerization at mitochondrial membranes and subsequent neuronal toxicity