Search Results (70)

Understanding the hierarchical patterns of building heights is essential for sustainable urban development and planning. This study presents a novel approach for detecting and comparing building height hierarchies in four major bay areas: the San Francisco Bay Area, the New York Bay Area in the United States, the Tokyo Bay Area in Japan, and the Guangdong-Hong Kong-Macau Greater Bay Area in China. Kernel density estimation was first used to create continuous spatial distributions of building heights, forming the basis for our analysis. The approach then uses the contour tree algorithm to abstract and visualize these hierarchies. A structural similarity index is proposed to compare the hierarchies by identifying the maximum common sub-contour tree across the different contour trees. The results reveal that all four bay areas exhibit a multi-core hierarchical structure, with the greater bay area exhibiting the most complex pattern. Quantitative comparison reveals that the building height hierarchies of the New York Bay Area and Tokyo Bay Area are most similar (similarity index = 0.74), while those of the San Francisco Bay Area and Greater Bay Area are the least similar (similarity index = 0.17). Our approach provides a practical tool for understanding building height hierarchies and can be readily applied to analyze diverse spatial patterns. Full article

Large-scale traffic simulations at a microscopic level can mimic the physical reality in great detail so that innovative transport services can be evaluated. However, the simulation times of such scenarios is currently too long to be practical. (1) Background: With the availability of Graphical Processing Units (GPUs), is it possible to exploit parallel computing to reduce the simulation times of large microscopic simulations, such that they can run on normal PCs at reasonable runtimes?; (2) Methods: ParSim, a microsimulator with a monolithic microsimulation kernel, has been developed for CUDA-compatible GPUs, with the aim to efficiently parallelize the simulation processes; particular care has been taken regarding the memory usage and thread synchronization, and visualization software has been optionally added; (3) Results: The parallelized simulations have been performed by a GPU with an average performance, a 24 h microsimulation scenario for Bologna with 1 million trips was completed in 40 s. The average speeds and waiting times are similar to the results from an established microsimulator (SUMO), but the execution time is up to 5000 times faster with respect to SUMO; the 28 million trips of the 24 h San Francisco Bay Area scenario was completed in 26 min. With cutting-edge GPUs, the simulation speed can possibly be further reduced by a factor of seven; (4) Conclusions: The parallelized simulator presented in this paper can perform large-scale microsimulations in a reasonable time on readily available and inexpensive computer hardware. This means microsimulations could now be used in new application fields such as activity-based demand generation, reinforced AI learning, traffic forecasting, or crisis response management. Full article

Intersectional oppression and invisibility are primary drivers of cognitive and mental health disparities that affect Black women’s wellness. Older Black women additionally experience compounding effects of ageism, which may place them at increased risk for a decline in cognitive functioning and mental wellness. To date, limited strengths-based, culturally relevant programming has focused on aging Black women. Fewer have incorporated Black women elders into conversations on Black liberation and the transformational change needed to create possible futures rooted in equity, healing, and health. This manuscript describes the inception and development of Radical Imagination, a creative aging program for Black women in the San Francisco Bay Area. Over ten weeks, 42 Black women (M age = 73.6, SD = 6.20; range: 58–85 years old) participated in the program, which incorporated brain and mental health education, art-making, storytelling, and photography. Grounded in principles of Afrofuturism and radical healing, participants explored past narratives of Black women and created a collective vision for a future that centers on Black women’s needs. Approximately 54.8% of participants attended more than one workshop. Upon program completion, exit surveys indicated that participants reported a moderate level of hopefulness about their ability to shape the future. Respondents reported overall satisfaction with the workshop series. We conclude with reflections on our process and recommendations for ways to support aging Black women using Afrofuturism and the arts. Full article

Genome editing technologies have revolutionized the production of microorganisms, plants, and animals with phenotypes of interest to agriculture. Editing previously sequenced genomes allows for the punctual, discreet, precise, and accurate alteration of DNA for genetic analysis, genotyping, and phenotyping, as well as the production of edited organisms for academic and industrial purposes, among many other objectives. In this context, genome editing technologies have been causing a revolution in Brazilian agriculture. Thanks to the publication of Normative Resolution No. 16 (in Portuguese Resolução Normativa No. 16-RN16) in 2018, Brazilian regulatory authorities have adapted to the new genetic manipulation technologies available to the scientific community. This review aims to describe the effects of updates to the regulatory framework for edited organisms in Brazil and to point out their impacts on research and development of emerging technologies in the Brazilian agricultural sector. The implementation of RN16 rationalized the regulatory aspects regarding the production, manipulation, exploration and commercial release of edited organisms and led to the faster, cheaper and safer obtaining of edited technologies, which are more productive and better adapted to different environmental conditions in Brazil. Full article

Beta attenuation monitors (BAMs) are widely used for the regulatory monitoring of fine particulate matter (PM_2.5) and fence line monitoring of industrial sites. The elemental analysis of BAM filter tapes potentially could enable additional source PM_2.5 attribution. However, the chemical characterization of the glass fiber filters is hindered by high background metal values. A sample preparation method was developed using the ultrasonic extraction of particulate matter from BAM filter spots in nitric acid and the analysis of metals by inductively coupled plasma–mass spectrometry (ICP-MS) and scanning electron microscopy–energy-dispersive X-ray spectroscopy (SEM-EDS). To demonstrate the utility of this method, BAM filter spots were analyzed from wildfire smoke periods in the San Francisco Bay Area in California in Fall 2023 and indicated elevated levels of chromium compared to a non-wildfire period in Spring 2023. The SEM-EDS of the BAM tape was used to probe individual particulate morphology, but it only detected Fe and Ba at levels above the blank media. The ultrasonic extraction method of BAM filter spots could be used in future wildfire smoke events to extend the characterization of beta attenuation monitor filters in PM_2.5 monitoring. Full article

Per- and polyfluoroalkyl substances (PFASs) are found everywhere, including food, cosmetics, and pharmaceuticals. This review introduces PFASs comprehensively, discussing their nature and identifying their interconnection with microplastics and their impacts on public health and the environment. The human cost of decades of delay, cover-ups, and mismanagement of PFASs and plastic waste is outlined and briefly explained. Following that, PFASs and long-term health effects are critically assessed. Risk assessment is then critically reviewed, mentioning different tools and models. Scientific research and health impacts in the United States of America are critically analyzed, taking into consideration the Center for Disease Control (CDC)’s PFAS Medical Studies and Guidelines. PFAS impact and activities studies around the world have focused on PFAS levels in food products and dietary intake in different countries such as China, European countries, USA and Australia. Moreover, PFASs in drinking water and food are outlined with regard to risks, mitigation, and regulatory needs, taking into account chemical contaminants in food and their impact on health and safety. Finally, PFAS impact and activities briefings specific to regions around the world are discussed, referring to Australia, Vietnam, Canada, Europe, the United States of America (USA), South America, and Africa. The PFAS crisis is a multifaceted issue, exacerbated by mismanagement, and it is discussed in the context of applying the following problem-solving analytical tools: the Domino Effect Model of accident causation, the Swiss Cheese Theory Model, and the Ishikawa Fish Bone Root Cause Analysis. Last but not least, PFASs’ impacts on the Sustainable Development Goals (SDGs) of 2030 are rigorously discussed. Full article

Background: Few studies have examined whether sleep is related to dietary intake in aging adults. To address this gap, this study investigated (1) the associations between sleep duration and sleep quality with fruits and vegetables (FV), fiber, and fat intake in lower-income midlife and older adults and (2) sex differences in these relationships. Methods: Baseline data from 163 ethnically diverse, lower-income midlife and older adults in the NIH-funded Steps for Change trial were analyzed. Dietary intake was assessed using the Block Fruit/Vegetable/Fiber and Fat Intake Screeners, operationalized as weekly servings. Sleep duration (hours per night) and quality were self-reported via the Stanford WELL for Life Scale. Linear regression models assessed the association between sleep duration and FV, fiber, and fat intake, adjusting for potential confounding covariates with separate models for sleep quality. Sex differences were tested using interaction terms, with stratified models also used to explore differences. Results: The sample was 73.2% female, with a mean age of 70.5 (SD = 9.7) years (range: 41–99). The mean sleep duration was 6.8 (1.2) hours per night, with 79.2% reporting fairly or very good sleep quality. Mean weekly servings were 24 for FV, 7 for fiber, and 18 for fat. Sleep duration was positively associated with FV intake (β = 2.2; p = 0.02). The interaction between duration and sex was marginally significant (p = 0.08), with a positive association in males (β = 5.5; p = 0.02) but not in females (β = 0.9; p = 0.41). No significant associations were found between sleep duration and fiber or fat intake or between sleep quality and any dietary intake outcomes. Conclusions: This study found that longer sleep duration was associated with higher FV intake in males but not in females. These findings suggest the possibility of sex differences in the sleep–diet relationship among aging populations that merit further exploration in longitudinal studies. Full article

The coastal regions of major bay areas—including San Francisco, Tokyo, New York, Guangdong–Hong Kong–Macao, and Hangzhou—are important centers of economic and social growth due to their strategic location, resources, and dynamic economies. However, the significant development disparities between the central cities and surrounding areas, as well as the challenges of climate change, highlight the need for a comprehensive assessment of their development potential. The aim of this study is to find out which cities have the strongest development potential and what the main factors influencing the results are. To address this research question, we use a combination of the Analytic Hierarchy Process (AHP) and the Entropy Weight Method (EWM) to systematically assess the development potential of 63 cities in five bay area regions and explore the mechanisms that influence it. The principal component analysis (PCA) also examines the global networking and sustainability mechanisms. The results show that Shenzhen and Shanghai lead in development potential due to strong institutional frameworks and global connectivity, but significant imbalances remain in the bay areas. Key contributors to sustainability and connectivity include air passenger traffic, public libraries, and port handling, while traditional economic metrics such as GDP growth show limited impact. These findings underscore the importance of prioritizing urban livability, resource circulation, and infrastructure over traditional economic indicators for sustainability and provide actionable insights for policy makers to promote balanced and sustainable development in bay area cities. Full article

Autonomous electric vehicles (AEVs) can potentially revolutionize the transportation landscape, offering a safer, contact-free, easily accessible, and more eco-friendly mode of travel. Prior to the market uptake of AEVs, it is critical to understand the consumer segments that are most likely to adopt these vehicles. Beyond market adoption, it is also important to quantify the impact of AEVs on broader transportation systems and the environment, such as impacts on the annual vehicle miles traveled (VMT) and greenhouse gas (GHG) emissions. In this pilot study, using survey data, a statistical model correlating AEV adoption intention and socioeconomic and built environment attributes was estimated, and a sensitivity analysis was conducted to understand the importance of factors impacting AEV adoption. We found that the market segments range from early adopters who are wealthy, technologically savvy, and relatively young to non-adopters who are more cautious to new technologies. This is followed by a synthetic population microsimulation of market penetration for the San Francisco Bay Area. With five household vehicle replacement scenarios, we assessed the annual VMT and tailpipe carbon dioxide (CO₂) emissions change associated with vehicle replacement. It is found that adopting AEVs can potentially reduce more than 5 megatons of CO₂ yearly, which is approximately 30% of the total CO₂ emitted by internal combustion engine (ICE) cars in the region. Full article

With so many studies today on the water quality of the sea, one can hardly comprehend the multitude of topics that arise all over the world. This study provides a few graphic syntheses related to the most frequent words (including their clustering and links), trend topics, the spatial distribution of the researched areas, and the thematic evolution of the research directions over the decades. The most frequent authors’ keywords have a 50% similitude between the ocean studies and the studies related to the Mediterranean Sea; these keywords are part of a causal chain that dominates the marine studies on water quality: nutrients → eutrophication → phytoplankton → chlorophyll → seagrass. The most frequent words in the titles and abstracts of the selected papers from the Web of Science are “concentration” and “species”; in the Mediterranean studies, “chlorophyll” and “temperature” are the most frequent. In close connection with water quality, Zostera marina (eelgrass) and Crassotrea virginica (eastern oyster) prevail at the global scale, while Posidonia oceanica (Neptune grass) is relevant in the Mediterranean space. Some of the most studied water bodies are the South China Sea, San Francisco Bay, Chesapeake Bay, and, in the Mediterranean Sea, the Adriatic, Ionian, Aegean, and Marmara seas. “Climate change” and “remote sensing” are trend topics that shape the current studies on water quality; the increasing sea surface temperature enhances algal blooms—these need to be monitored using satellite imagery for the sustainable evolution of human activities, including aquaculture. Full article

The purpose of this study was to understand how the challenges and coping strategies among international students in the United States changed before and during the COVID-19 pandemic. We conducted a qualitative study through one-on-one in-depth interviews during April–June 2021. A total of 34 international students in the San Francisco Bay Area participated in this study. NVivo was used to analyze the qualitative data. Before COVID-19, the challenges were primarily related to a sense of belonging, such as culture shock, language barriers, and loss of identity. However, some positive experiences from school life and new culture were also found before COVID-19. During the pandemic, students faced difficulties with online learning and lockdown protocols that they had never experienced before. The ongoing challenges before and during COVID-19 were identity crisis, racism and discrimination, and financial struggles. Common coping strategies for overcoming these difficulties included engaging in physical activity, social exposure, self-improvement, and mental self-care. The frequency of online engagement and motivation for self-improvement were particularly highlighted during COVID-19. However, international students expressed a preference for improved support systems, including financial aid, paid research opportunities, and more accessible campus resources. Future research could focus on the strategies to support the psychological well-being of international students in coping with unexpected situations, such as disease outbreaks. Full article

With urbanization and increased vehicle usage, understanding the exposure to air pollutants inside the vehicles is vital for developing strategies to mitigate associated health risks. In-vehicle air quality influences the comfort of the driver during long commutes and has gained significant interest. This study focuses on studying in-vehicle air quality in the San Francisco Bay Area in California, an urban setting with significant traffic congestion and varied emission sources and road conditions. Each trip is about 80.5 km (50 miles) in length, with commute times of approximately one hour. Two low-cost portable sensors were employed to simultaneously measure in-vehicle pollutants (PM_2.5, PM₁₀, and CO₂) during morning and evening rush hours from May 2023 to December 2023. Seasonally averaged PM_2.5 varied from 5.07 µg/m³ to 6.55 µg/m³ during morning rush hours and from 4.38 µg/m³ to 4.47 µg/m³ during evening rush hours. In addition, the impacts of local PM_2.5, vehicle ventilation settings, and speed of the vehicle on in-vehicle PM concentrations were also analyzed. CO₂ buildup in vehicles was studied for two scenarios: one with inside recirculation enabled (RC on) and the other with circulation from outside (RC off). With RC off, CO₂ concentrations are largely within the 1100 ppm range recommended by many organizations, while the average CO₂ concentrations can be three times high under recirculation mode. This research suggests that low-cost sensors can provide valuable insights into the dynamics of air pollution in the in-vehicle microenvironment, which can better help commuters reduce health risks. Full article

This investigation explored (1) correlations between midlife and older adults’ air quality perceptions with objective particulate matter 2.5 (PM_2.5) and diesel PM, and (2) correlations between air quality perceptions with health-related attributions among a sample of midlife and older adults (n = 66) living in or around senior affordable public housing sites in California’s San Francisco Bay Area. The adapted air quality perception scale was used to measure perceptions of air quality, while health-related attributions were obtained from the vitality plus scale (VPS), with higher values indicating worse perceptions of air quality and poorer responses to health-related attributions, respectively. Self-reported data were linked to zip code level PM_2.5 and diesel PM obtained from the CalEnviroScreen 4.0. All correlations were evaluated using Spearman’s rank correlations. The mean (SD) age was 70.6 (9.1) years, and 75.7% were female. We observed moderate, positive correlations between both PM_2.5 and diesel PM with three domains: perceptions related to protection measures against air quality, emotional/mental perceptions, and sensorial perceptions. We also found evidence of moderate, positive correlations between the domains of physical symptoms, perceptions related to protection measures against air quality, and emotional/mental perceptions with health-related attributions, such as sleep-related items and feelings of restlessness or agitation. Results from this exploratory study suggest that midlife and older adults’ perceptions of air quality may be moderately related to both objective air quality data and certain health behaviors and symptoms. Findings underscore the importance of considering individual perceptions as an additional area in public health strategies aimed at protecting midlife and older adults from the impacts of air pollution. Full article

San Francisco Bay’s sediment is currently monitored for a variety of contaminants; however, data regarding the microplastics (MPs) in the area are still scarce. MPs’ occurrence in sediment samples has gained recognition as a reservoir for MP accumulation. Moreover, Bay sediment is also an important matrix for monitoring because sediment tends to accumulate certain contaminants and act as a source of contaminants in the Bay food web. This study analyzed MPs ranging from 25 µm to 5 mm in surface sediment grab samples (n = 8) and two sediment core samples (n = 2 cores analyzed with 11 samples from different depths). Our findings provide an evaluation of MP levels in different regions of the bay. The MP levels detected in Bay surface grab samples ranged from 2.1 to 11.9 MPs/g dry weight (n = 8), with a mean value of 6.2 MPs/g. The most abundant morphology was fibers, followed by fragments and films. Full article

This study focuses on the impact of wildfire smoke emissions on regional, urban air quality during a wildfire event. We measured volatile organic compounds (VOCs) and fine particulate matter (PM_2.5) in the San Francisco Bay Area to assess air quality during a wildfire event and compared them to those in a later non-wildfire period. VOCs were collected using thermal desorption tubes and quantified using thermal desorption-gas chromatography/mass spectrometry (TD-GC/MS). Elevated concentrations of VOCs such as 1,3,5-trimethylbenzene (0.33 ± 0.01 µg/m³), benzene (1.03 ± 0.02 µg/m³), toluene (2.15 ± 0.04 µg/m³), ethylbenzene (0.60 ± 0.02 µg/m³), and m, p-xylene (0.77 ± 0.07 µg/m³) were observed in the wildfire event. Compared with that in the non-wildfire season, the toluene concentration during the wildfire period was more than three times the non-wildfire concentration. Similarly, the benzene concentration during the wildfire was almost four times higher, and that of p, m-xylene was three times higher. The higher wildfire levels were statistically significant for sec-butylbenzene, 1,2,4-trimethylbenzene, n-propylbenzene, o-xylene, styrene, 1,3,5-trimethylbenzene, benzene, toluene, ethylbenzene, and p,m-xylene (p < 0.00001). These higher VOC levels compared with those for the non-fire period may potentially pose a public health concern. Open face passive sampler (OFPS)-collected PM was analyzed using scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDS) and revealed organic carbon tar balls. The highest daily average beta-attenuation-monitored PM_2.5 during the fire period was 200 µg/m³ and the highest hourly average was 270 µg/m³. Monitoring gas phase species in addition to PM concentrations is useful during wildfire season to inform public health guidance. Full article