Beijing's power system has experienced a significant transition by eliminating coal-fired power generation and increasing the extent of electrification over the past two decades. This study uses a plant-level dataset, pair-wise energy flow, and customized index decomposition analysis to investigate the driving forces behind Beijing's rapid electrification and carbon mitigation effects. Our assessment approaches can reveal the role of electrification in driving city-level emissions and identify a reasonable timeline to accelerate electrification for cities. We find that electrification-related factors are responsible for 21.8% of carbon emission changes in Beijing between 1995 and 2019. The extent of electrification in Beijing has doubled from 9.5% in 1995 to 19% in 2019, while the carbon intensity of electricity consumption has reduced by 26%. Particularly, the average emission intensity of Beijing's local power generation has dropped from 860 tCO2e/GWh in 2000 to 370 tCO2e/GWh in 2018, which is far below a critical level at which the high penetration of electricity in transportation and housing should be prioritized for decarbonization. Our results confirm that Beijing is in the best position to accelerate electrification to meet its carbon neutrality goals; however, this will increasingly rely on regionally collaborative decarbonization efforts with surrounding regions.
A test was administered to 102 engineering students to ascertain how engineering education influences their environmental knowledge and attitudes. Answers to definitional and factual questions in a forced-answer section demonstrated that students were improving their technical knowledge, but responses to more subtle questions were mixed. Answers to attitudinal questions exhibited a trend towards increased environmental awareness. For open-ended questions, posttest results showed an increase in knowledge of engineering work. Over 80% of the students considered themselves to have a caring attitude toward the environment, with the “three R’s” and green transportation choices most commonly cited. Engagement in research, education, or advocacy doubled from pretest to posttest. Air pollution and solid waste disposal most frequently influenced students’ attitudes toward the environment. Outdoor experiences were the most frequently mentioned source of information; university courses rose from 4% to 15% on the posttest. Only 40% of the students could name an environmental role model.
Establishing appropriate subsidies for transit systems is essential to determine levels of investment and operations budgets for such systems. Transit subsidies vary significantly among cities around the world, generally being lowest in Asia and highest in Australia and North America. The potential economic rationale for subsidizing urban transit results from increasing returns to scale, positive externalities, and second-best pricing. In spite of low cross-elasticities of demand among modes, the second-best pricing argument is perhaps the strongest, given the absence of congestion pricing in most cities. Three models for calculating optimal subsidies are compared in terms of their mathematical form, assumptions, and input and output variables. Applying any of the models requires demand modeling and careful definition of costs. One model is identified as being the most practical, another is useful for research, and the third is perhaps better for explaining principles.
Some cities seem destined to become major financial capitals, yet never do-Seville, for instance, was the centre of Spain's opulent New World Empire, but failed to become a financial metropolis. Others, like former colonial backwater Hong Kong, defy the odds by growing into major trading centres. What are the key factors distinguishing those cities that become wealthy from those that don't? Christopher Kennedy illuminates how geography, technology, and especially the infrastructure of urban economies allow cities to develop and thrive. The Evolution of Great World Cities unfolds through the tales of several urban centres-including Venice, Amsterdam, London, and New York City-at key junctures in their histories. Kennedy weaves together significant insights from urbanists such as Jane Jacobs and economists such as John Maynard Keynes, drawing striking parallels between the functioning of ecosystems and of wealthy capitals. The Evolution of Great World Cities offers an accessible introduction to urban economies that 'will change the way you think about cities.'
Abstract Carbon emissions are currently attributed to producers although a consumption-aware accounting is advocated. After constructing the Carbon Trade Network, we trace the flow of emissions over the past two decades. Our analysis reveals the presence of an unexpected, positive feedback: despite individual exchanges have become less carbon-intensive, the increase in trading activity has ultimately risen the amount of emissions directed from 'net exporters' towards 'net importers'. Adopting a consumption-aware accounting would re-distribute responsibility between the two groups, possibly reducing disparities.
China's green investment needs up to 2020 are ¥1.7 trillion–2.9 trillion CNY ($274 billion–468 billion USD) per year. Estimates of financing requirements are provided for multiple sectors, including sustainable energy, infrastructure (including for environmental protection), environmental remediation, industrial pollution control, energy and water efficiency, and green products. The context to China's green financing is discussed, covering urbanization, climate change, interactions between infrastructure sectors, and the transformation of industry. Much of the infrastructure financing will occur in cities, with a focus on equity, environmental protection, and quality of life under the National New-Type Urbanization Plan (2014–2020). China has implemented many successful policies in the building sector, but there is still considerable scope for improvement in the energy efficiency of Chinese buildings. China is currently pursuing low-carbon growth strategies that are consistent with its overall environmental and quality-of-life objectives. Beyond 2020, China's future as an ecologically balanced civilization will rest on the implementation of a central infrastructure policy: China 2050 High Renewable Energy Penetration Scenario and Roadmap Study. As exemplified by the Circular Economy Development Strategy and Near-Term Action Plan, an essential part of China's green industrial transformation involves engineering systems that conserve materials, thereby reducing or even eliminating wastes. To better understand changes to China's economy under its green transformation and to unlock large potential sources of finance, it is necessary to undertake a fuller examination of all of China's infrastructure sectors, particularly freight rail infrastructure and ports. Large investments are required to clean up a legacy of environmental contamination of soil and groundwater and to reduce industrial pollution. Transformation of the power sector away from coal will avoid some industrial treatment costs. The contribution of engineers in planning, designing, and constructing China's new green infrastructure will be furthered by understanding the broad policy context and the interactions between land use, infrastructure, and environmental performance.
According to the guidelines of the Intergovernmental Panel on Climate Change, carbon emissions are attributed to the producers of goods and services. This approach has been challenged by recent literature, advocating an attribution criterion based on consumers, i.e. accounting for the carbon embedded into the goods imported by each country. Quantifying the effectiveness of such a consumption-based accounting requires understanding the complex structure of the graph induced by the flows of emissions between world countries. To this aim, we have considered a balanced panel of a hundred of countries and constructed the corresponding Carbon Trade Network for each of the past twenty years. Our analysis highlights the tendency of each country to behave either as a 'net producer'-or 'net exporter'-of emissions or as a 'net consumer'-or 'net importer'-of emissions; besides, it reveals the presence of an unexpected, positive feedback: despite individual exchanges having become less carbon-intensive, the increasing trade activity has ultimately risen the amount of emissions directed from 'net exporters' towards 'net importers'. Adopting a consumption-aware accounting would re-distribute responsibility between these two groups, possibly reducing disparities.
Over three years since the World Health Organization (WHO) declared COVID-19 a pandemic, it is still a global burden. Vaccines against COVID-19, caused by SARS-CoV-2, are available and effective for preventing disease. However, their protective effects are not 100%. Currently, the U.S. Food and Drug Administration (FDA) has only approved a limited number of inpatient treatments for COVID-19, such as remdesivir, baricitinib, and tocilizumab. These medications have indications and contraindications applicable to a select patient population. Finding additional effective therapies that are widely available with limited risk could be vital in optimizing treatment strategies for this viral illness. Some vitamins and supplements have been identified as potential options for managing COVID-19. Vitamin D (VD) deficiency has been associated with respiratory tract infections. Moreover, alpha-lipoic acid (ALA) is a powerful antioxidant and helps reduce inflammatory responses in many pathologic conditions. This review aims to analyze the current evidence regarding the effectiveness of VD and alpha-lipoic acid in COVID-19 infection in both outpatient and hospitalized patients. Relevant randomized controlled trials (RCTs) were identified via the PubMed database from January 1, 2021, to December 31, 2023. Inclusion criteria were as follows: the study design was a randomized controlled trial (RCT), the usage of a constant dose during the intervention period without any additional boluses, and a research ethics committee approved it. Exclusion criteria included a lack of an outcome or apparent intervention, additional boluses, or a single-dose regimen in all the interventional groups. There were 11 studies with a total sample size of 35,717 patients that met the criteria for this review. A total of 10 RCTs examined the efficacy of VD, and one RCT that reviewed the efficacy of ALA was identified. All of the articles investigated the use of VD or ALA during the treatment of COVID-19. The endpoints of each study varied, including length of stay in hospital, viral load, SARS-CoV-2 infection rate, mechanical ventilation, inflammatory markers, clinical symptoms, Sequential Organ Failure Assessment (SOFA) score, and mortality. In 8/10 VD supplementation trials, significant differences were identified between the interventional and placebo groups in the aforementioned parameters. In 2/10 VD supplementation trials, no significant differences were identified. The ALA supplementation RCT found no differences between the interventional and placebo groups in the SOFA score and 30-day all-cause mortality rate. The current literature suggests that VD can potentially reduce the SARS-CoV-2 infection rate, oxygen requirements, inflammatory markers, clinical symptoms, and mortality. Regarding ALA, although there was a suggestion of benefit, it was not statistically significant. Common limitations among the different studies included relatively small sample sizes, different geographical patient locations among studies, and differences in dosages. Trials investigating the effects of higher doses of VD supplementation on SARS-CoV-2 infection should be conducted. More research is needed to define best practices and optimal dosing protocols for the use of VD in COVID-19.
Energy is required both to build the capital stock and to produce goods and services from the use of the capital stock. These two energy demands are together constrained by the available energy in the macroeconomy. Here, I develop a mathematical theory expressing the relationship between available energy and the capital stock as a first-order differential equation. Three specific solutions are derived for the cases of a steady-state economy with fixed capital stock, for an economy with a linearly increasing capital stock, and for an exponentially growing capital stock. Empirical data for the United Kingdom's nineteenth century economy are used to examine the energy required to access energy supplies; the energy intensity of capital formation; and the energy intensity of capital use. Magnitudes and trends in the energy intensity of capital use differ for four sectors of the economy—mining, residential, utilities, and railways. Data for the United Kingdom's ratio of available energy to capital from 1850 to 1913, are examined for the case of a linearly increasing capital stock. This corroborates the overall theoretical model and demonstrates that the change in energy to capital ratio is impacted by the magnitude of the capital stock. Further analysis of the mining sector shows that higher coal prices follow after increases in capital investment and increased coal production. This helps demonstrate how energy constraints play out in the macroeconomy. This article met the requirements for a gold – gold JIE data openness badge described at http://jie.click/badges.
