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Urban growth strategy in Greater Sydney leads to unintended social and environmental challenges
Cities have advanced in terms of economic and social status over the past five decades, improving the living conditions of hundreds of millions of people. However, population growth and urban expansion have put pressure on social and environmental conditions. This study examines urban policymakers’ perceptions about causal relationships in the urban system as revealed in urban planning reports. Here we analyzed 500 pages from published urban plans of Greater Sydney between 1968 and 2018 and coded the text into causal maps. The findings show that policymakers adopted a dominant urban development strategy over the past 50 years to pursue economic and public infrastructure growth. Over time, this growth strategy resulted in a number of social and environmental challenges that negatively impacted societal well-being. Although policymakers eventually recognized the seriousness of social and environmental challenges, they never attempted to fundamentally change the dominant growth strategy. Instead, policymakers sought to address the challenges (that is, symptoms) by responding to each issue piecemeal.
The decreasing housing utilization efficiency in China’s cities
‘Ghost cities’ are a well-known phenomenon of (almost) complete vacancy of urban living space in China. Underutilization of urban living space, however, is far more common than complete vacancy. Here we propose the concept of housing utilization efficiency (HUE) and present the following findings: (1) the overall HUE in China’s highly urbanized areas decreased from 84% in 2010 to 78% in 2020, (2) the HUE in central, old urban areas was generally lower than that in the outer layers of urban areas and declined more from 2010 to 2020 and (3) four development types are found to represent different patterns of urban population movement, urban housing growth and HUE change at the intraurban level. These findings provide comprehensive insight into the discrepancies between urban housing supply and demand in China and highlight their connections to the country’s particular urbanization characteristics and policies, which are crucial for future housing development and planning.
Decoding the mechanism of proanthocyanidins in central analgesia: redox regulation and KCNK3 blockade
Neuropathic pain causes enduring physical discomfort and emotional distress. Conventional pharmacological treatments often provide restricted relief and may result in undesirable side effects, posing a substantial clinical challenge. Peripheral and spinal redox homeostasis plays an important role in pain processing and perception. However, the roles of oxidative stress and antioxidants in pain and analgesia on the cortical region during chronic pain remains obscure. Here we focus on the ventrolateral orbital cortex (VLO), a brain region associated with pain severity and involved in pain inhibition. Using a spared nerve injury mouse model, we observed the notable reactive oxygen species (ROS)-mediated suppression of the excitability of pyramidal cells (PYRVLO) in the VLO. Nasal application or microinjection of the natural antioxidants proanthocyanidins (PACs) to the VLO specifically increased the activity of PYRVLO and induced a significant analgesic effect. Mechanistically, PACs activate PYRVLO by inhibiting distinct potassium channels in different ways: (1) by scavenging ROS to reduce ROS-sensitive voltage-gated potassium currents and (2) by acting as a channel blocker through direct binding to the cap structure of KCNK3 to inhibit the leak potassium current (Ileak). These results reveal the role of cortical oxidative stress in central hyperalgesia and elucidate the mechanism and potential translational significance of PACs in central analgesia. These findings suggest that the effects of PACs extend beyond their commonly assumed antioxidant or anti-inflammatory effects.
Parallel scaling of elite wealth in ancient Roman and modern cities with implications for understanding urban inequality
Rapid urbanization and rising inequality are pressing global concerns, yet inequality is an ancient trait of city life that may be intrinsically connected to urbanism itself. Here we investigate how elite wealth scales with urban population size across culture and time by analyzing ancient Roman and modern cities. Using Bayesian models to address archeological uncertainties, we uncovered a consistent correlation between population size and physical expressions of elite wealth in urban spaces. These patterns suggest the presence of an ancient, enduring mechanism underlying urban inequality. Supported by an agent-based network simulation and informed by the settlement scaling theory, we propose that the observed patterns arise from common preferential attachment in social networks—a simple, yet powerful, driver of unequal access to interaction potential. Our findings open up new directions in urban scaling research and underscore the importance of understanding long-term urban dynamics to chart a course toward a fairer urban future.
Toward change in the uneven geographies of urban knowledge production
More than four-fifths of the global urban population live in the Global South and East. Most urban theories, however, originate in the Global North. Building on recent efforts to address this mismatch, this paper examines the geographies of urban knowledge production. It analyzes the institutional affiliations of contributions in 25 leading Anglophone journals (n = 14,582) and nine urban handbooks (n = 252). We show that 42% of the journal articles and 17% of the handbook chapters were authored outside the Global North. However, only 15% of the editor positions (handbooks: 10%) were held by scholars based outside the Global North. This indicates that Global Northern institutions still dominate knowledge gatekeeping, whereas authors are more diverse. Additionally, more empirical journals and those with fewer Northern board members tend to publish more non-Northern authors. Our findings underscore the need for greater epistemic diversity in gatekeeping positions and broader understandings of what counts as theory to better incorporate diverse urban knowledge.
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