Air Pollution and Mental Health of Older Adults in China

In this paper, we explore the association between air pollution and the mental health and depression of older adults in China. Along with the rapid economic development, concerns about air pollution and recognition of the importance of mental health have risen remarkably in China. Although no firm evidence of an association between air pollution and overall mental health has been found, the results show significant evidence of a positive relationship between air pollution and depression. Moreover, we observe the presence of concerns about environmental inequality, as people are more sensitive to contaminations caused by pollutants with high variation in densities across counties, such as PM2.5, PM10, and SO2. Although O3 has a high average absolute density, the impact on mental health is low due to the limited variations nationwide. Physical fitness, gender, relative income, marital status, and social contacts are also found to be related to mental health and depression of older adults

Teaching Energy Economics in the Gcc: A Synergistic Approach between Engineering and Economics

Issues related to safe and abundant energy production have been prominent in recent years. This is particularly true when society considers how to increase the quality of life by providing low-cost energy to citizens. A significant concern of the Gulf Cooperation Council (GCC) relates to the environmental effects of energy production and energy use associated with climate change. Efforts to reduce fossil fuel use and increase the use of renewable energy, together with the price volatility of fossil fuels, have seriously impacted the economics of many oil-producing countries, particularly the Gulf States, which has led to efforts to make their economies more diverse and less dependent on oil production. In this article, we introduce a multidisciplinary energy economics course developed at the Missouri University of Science and Technology that can be easily adopted by GCC universities to enhance future generations\u27 understanding of energy challenges

Gender in development discourses of civil society organizations and Mekong hydropower dams

'Gender in development' discourses are used to justify interventions into, or opposition to, projects and policies; they may also influence perceptions, practices, or key decisions. Four discursive threads are globally prominent: livelihoods and poverty; natural resources and the environment; rights-based; and managerial. Civil society organisations (CSOs) have been vocal in raising awareness about the adverse impacts of large-scale hydropower developments on the environment, on local livelihoods, and on vulnerable groups including women. This discourse analysis first examines how CSOs engaging in hydropower processes in the Mekong Region frame and use gender in development discourses, and then evaluates the potential of these discourses to empower both women and men. Documents authored by CSOs are examined in detail for how gender is represented, as are media reports on CSO activities, interview transcripts, and images. The findings underline how CSOs depend on discursive legitimacy for influence. Their discursive strategies depend on three factors: the organizations’ goals with respect to development, gender, and the environment; whether the situation is pre- or post-construction; and, on their relationships with the state, project developers and dam-affected communities. The implications of these strategies for empowerment are often not straightforward; inadvertent and indirect effects, positive and negative, are common. The findings of this study are of practical value to CSOs wishing to be more reflexive in their work and more responsive to how it is talked about, as it shows the ways that language and images may enhance or inadvertently work against efforts to empower women

Advances in Energy Hybridization for Resilient Supply: A Sustainable Approach to the Growing World Demand

Energy poverty, defined as a lack of access to reliable electricity and reliance on traditional biomass resources for cooking, affects over a billion people daily. The World Health Organization estimates that household air pollution from inefficient stoves causes more premature deaths than malaria, tuberculosis, and HIV/AIDS. Increasing demand for energy has led to dramatic increases in emissions. The need for reliable electricity and limiting emissions drives research on Resilient Hybrid Energy Systems (RHESs), which provide cleaner energy through combining wind, solar, and biomass energy with traditional fossil energy, increasing production efficiency and reliability and reducing generating costs and emissions. Microgrids have been shown as an efficient means of implementing RHESs, with some focused mainly on reducing the environmental impact of electric power generation. The technical challenges of designing, implementing, and applying microgrids involve conducting a cradle-to-grave Life Cycle Analysis (LCA) to evaluate these systems\u27 environmental and economic performance under diverse operating conditions to evaluate resiliency. A sample RHES was developed and used to demonstrate the implementation in rural applications, where the system can provide reliable electricity for heating, cooling, lighting, and pumping clean water. The model and findings can be utilized by other regions around the globe facing similar challenges

A Novel Approach to Interface High-Q Fabry-P\'erot Resonators with Photonic Circuits

The unique benefits of Fabry-P\'erot resonators as frequency-stable reference cavities and as an efficient interface between atoms and photons make them an indispensable resource for emerging photonic technologies. To bring these performance benefits to next-generation communications, computation, and timekeeping systems, it will be necessary to develop strategies to integrate compact Fabry-P\'erot resonators with photonic integrated circuits. In this paper, we demonstrate a novel reflection cancellation circuit that utilizes a numerically optimized multi-port polarization-splitting grating coupler to efficiently interface high-finesse Fabry-P\'erot resonators with a silicon photonic circuit. This circuit interface produces spatial separation of the incident and reflected waves, as required for on-chip Pound-Drever-Hall frequency locking, while also suppressing unwanted back reflections from the Fabry-P\'erot resonator. Using inverse design principles, we design and fabricate a polarization-splitting grating coupler that achieves 55% coupling efficiency. This design realizes an insertion loss of 5.8 dB for the circuit interface and more than 9 dB of back reflection suppression, and we demonstrate the versatility of this system by using it to interface several reflective off-chip devices

Lipid and glucose metabolism in senescence

Senescence is an inevitable biological process. Disturbances in glucose and lipid metabolism are essential features of cellular senescence. Given the important roles of these types of metabolism, we review the evidence for how key metabolic enzymes influence senescence and how senescence-related secretory phenotypes, autophagy, apoptosis, insulin signaling pathways, and environmental factors modulate glucose and lipid homeostasis. We also discuss the metabolic alterations in abnormal senescence diseases and anti-cancer therapies that target senescence through metabolic interventions. Our work offers insights for developing pharmacological strategies to combat senescence and cancer

The connection between tricarboxylic acid cycle enzyme mutations and pseudohypoxic signaling in pheochromocytoma and paraganglioma

Pheochromocytomas and paragangliomas (PPGLs) are rare neuroendocrine tumors originating from chromaffin cells, holding significant clinical importance due to their capacity for excessive catecholamine secretion and associated cardiovascular complications. Roughly 80% of cases are associated with genetic mutations. Based on the functionality of these mutated genes, PPGLs can be categorized into distinct molecular clusters: the pseudohypoxia signaling cluster (Cluster-1), the kinase signaling cluster (Cluster-2), and the WNT signaling cluster (Cluster-3). A pivotal factor in the pathogenesis of PPGLs is hypoxia-inducible factor-2α (HIF2α), which becomes upregulated even under normoxic conditions, activating downstream transcriptional processes associated with pseudohypoxia. This adaptation provides tumor cells with a growth advantage and enhances their ability to thrive in adverse microenvironments. Moreover, pseudohypoxia disrupts immune cell communication, leading to the development of an immunosuppressive tumor microenvironment. Within Cluster-1a, metabolic perturbations are particularly pronounced. Mutations in enzymes associated with the tricarboxylic acid (TCA) cycle, such as succinate dehydrogenase (SDHx), fumarate hydratase (FH), isocitrate dehydrogenase (IDH), and malate dehydrogenase type 2 (MDH2), result in the accumulation of critical oncogenic metabolic intermediates. Notable among these intermediates are succinate, fumarate, and 2-hydroxyglutarate (2-HG), which promote activation of the HIFs signaling pathway through various mechanisms, thus inducing pseudohypoxia and facilitating tumorigenesis. SDHx mutations are prevalent in PPGLs, disrupting mitochondrial function and causing succinate accumulation, which competitively inhibits α-ketoglutarate-dependent dioxygenases. Consequently, this leads to global hypermethylation, epigenetic changes, and activation of HIFs. In FH-deficient cells, fumarate accumulation leads to protein succination, impacting cell function. FH mutations also trigger metabolic reprogramming towards glycolysis and lactate synthesis. IDH1/2 mutations generate D-2HG, inhibiting α-ketoglutarate-dependent dioxygenases and stabilizing HIFs. Similarly, MDH2 mutations are associated with HIF stability and pseudohypoxic response. Understanding the intricate relationship between metabolic enzyme mutations in the TCA cycle and pseudohypoxic signaling is crucial for unraveling the pathogenesis of PPGLs and developing targeted therapies. This knowledge enhances our comprehension of the pivotal role of cellular metabolism in PPGLs and holds implications for potential therapeutic advancements

Research on the Macro-Mesoscopic Response Mechanism of Multisphere Approximated Heteromorphic Tailing Particles

AbstractThe shape of tailing particles is essential factors of their macroscopic mechanical properties. Scholars have studied the effects of controllable factors, such as loading method, confining pressure, and strain rate, on the strength of tailing sand. However, research on the tailing particle structure and shape through laboratory tests has proved to be difficult due to the uncertain and discrete tailing particle distribution. Thus, the macro-mesoscopic response of heteromorphic tailing particles is rarely investigated. In this paper, the macro-mesoscopic response of heteromorphic tailing particles is studied using multisphere approximation, and numerical simulation of triaxial tests on the particles is conducted. Nonlinear evolution patterns of porosity, internal friction angle, and cohesion of heteromorphic tailing particles with the variation of angularity were investigated using the flexible boundary program developed in this study, which revealed the intrinsic relationship between the mesostructure evolution mechanism and the macroscopic engineering characteristics of heteromorphic tailing particles. The research results showed that (1) changes in angularity led to tailing particle rearrangements and, in turn, porosity changes. With increased angularity and confining pressure, particle sphericity decreased, and the deviatoric and peak stress increased accordingly. In the meantime, the softening was more significant as the peak stress was exceeded, while the cohesive force generally increased. (2) With fixed particle shape and angularity, the internal friction angle decreased slightly as the effective confining pressure increased. (3) In the shearing process, the simulated contact force chain evolution of tailing particles with different shapes was similar. The disordered contact force chains gradually undergo directional connection, i.e., the increased confining pressure reduced the number of free tailing particles and increased the number of stressed particles. (4) The triaxial stress-strain and peak stress in rigid boundary simulations under different confining pressures were slightly lower than those in the flexible boundary simulations. However, the difference was insignificant, indicating the good feasibility and reasonability of rigid boundary simulations for the macroscopic mechanical behaviors in triaxial tests. The research results could offer more direct insights into the macro-mesoscopic response and mechanical mechanisms of nonspherical particles and provide references for the simulation of tailings at the microscopic levels

Three Essays on the Efficiency of Carbon Emission Trading Programs

Using individual level data from electricity generators, my dissertation empirically investigates the effectiveness of existing regional environmental policies in the U.S. electricity wholesale markets aiming to reduce CO2 emissions. Big drop of natural gas price and limited magnitude and variation of CO2 allowance prices make the contribution of CO2 cap and trade programs questionable. Given the complexity of the electricity markets, the central of my research is to decompose the co-existing various effects on individual firms\u27 emissions and evaluate the performance of current regional regulations. I particularly study the Regional Greenhouse Gas Initiative (RGGI), which regulates power plants in nine northeastern states of the U.S.. The first chapter measures the impact of carbon emission regulation on U.S. power plants\u27 technical efficiency. No evidence of technical efficiency changes due to the RGGI regime in the RGGI area is found. Using a difference-in-difference framework in chapter two, we find that overall the RGGI program leads to 7.72 million short tons of CO2 reduction per year in Delaware and Maryland, or about 34.36% of the average total annual emissions in these two states. All utilities respond to the program by decreasing their heat input per capacity even including natural gas utilities. Chapter 3 studies electricity generators\u27 production behavior and how the decisions are altered with CO2 emission regulations. The results show that the RGGI policy has helped to decrease the total CO2 emissions by at least 4.73% during the sample period. All other things equal, an additional \$1/ton increase in permit price reduce the total CO2 emissions by 1.85%