Search Results (158)

Antimicrobial resistant (AMR) infections are a persistent public health issue causing excess death and economic impacts globally. Because AMR in clinical settings is often acquired from nonpathogenic bacteria that surround us, environmental surveillance must be better characterized. It has been well established that metals can co-select for bacterial AMR. Furthermore, recent studies have shown that compromised microbial community diversity may lead to community invasion by antibiotic resistance genes (ARGs). Widespread legacy mining has led to acid mine drainage and metal contamination of waterways and sediments throughout the western United States, potentially compromising microbial community diversity while simultaneously selecting for AMR bacteria. Our study objectives were to survey metal contaminated sediments from the Bonita Peak Mining District (BPMD) in southwestern Colorado, USA, compared to sites downstream in Durango, CO for bacterial and ARG diversity. Sediment bacteria were characterized using 16S rRNA Ilumina and metagenomic sequencing. We found that overall, bacterial diversity was lower in metal-contaminated, acidic sites (p = 0.04). Metagenomic sequencing revealed 31 different ARGs, with those encoding for efflux pumps (mex and spe gene families) substantially more prevalent in the BPMD sites, elucidating a specific AMR marker fingerprint from the high metal concentration sediments. Raising awareness and providing antimicrobial tracking techniques to resource limited communities could help provide information needed for better antibiotic use recommendations and environmental monitoring. Full article

The Weather Research and Forecasting Model (WRF-ARW) version 4.5 was used to simulate the synoptic to mesoscale evolving atmosphere of Tropical Cyclone (TC) Hilary’s (2023) remnant passage over the southwestern United States. The atmospheric dynamic processes conducive to the precursor rain events were extensively studied to determine the effects of mid-level jetogenesis. Concurrently, the dynamics of mesoscale processes related to the interaction of TC Hilary over the complex topography of the western United States were studied with several sensitivity simulations on a nested 2 km × 2 km grid. The differential surface heating between the cloudy California coast and clear/elevated Great Basin plateau had a profound impact on the lower-mid-tropospheric mass field resulting in mid-level jetogenesis. Diagnostic analyses of the ageostrophic flow support the importance of both isallobaric and inertial advective forcing of the mid-level jetogenesis in response to differential surface sensible heating. This ageostrophic mesoscale jet ultimately transported tropical moisture in multiple plumes more than 1000 km poleward beyond the location of the extratropical transition of the storm, resulting in anomalous flooding precipitation within a massive arid western plateau. Full article

Wide thermal cracks are a common form of pavement distress affecting primary state and county highways, urban residential streets, and parking lots across the Southwest climatic regions. These cracks are primarily caused by thermal fatigue, driven by diurnal temperature variations despite the lack of extremely cold events. This research aims to identify and analyze the local factors contributing to the initiation and propagation of thermal fatigue cracks. Field cores are collected from 12 sites exhibiting wide thermal cracks in the Phoenix metropolitan area in Arizona to evaluate their volumetric properties and the degree of binder aging. Advanced finite element (FE) models were developed to examine the influence of pavement structures and local climatic conditions on the development of tensile stresses due to thermal fatigue. The FE analysis indicated a high magnitude of thermal stresses due to cyclic temperature variations in Arizona compared to colder regions in the United States. Based on the forensic investigation and analysis performed, the initiation of wide cracks was shown to be primarily due to repeated localized damage from frequent thermal fatigue events on severely aged pavements. This damage is exacerbated by low air voids in mineral aggregate, an insufficient effective binder volume. and excessive binder aging, which compromise the structural integrity of the pavement. Full article

Urban flooding is a major challenge to sustainable development in rapidly urbanizing cities. This study applies an integrated approach that combines Sentinel-1 SAR data, geomorphological analysis, and the DPSIR (Drivers–Pressures–State–Impacts–Responses) framework to assess the relationship between urbanization and flooding in Hanoi during the 2010–2024 period (with Sentinel-1 time-series data for 2015–2024). A time series of Sentinel-1 images (2015–2024) was processed on Google Earth Engine to detect inundation and construct a flood frequency map, which was validated against 148 field survey points (overall accuracy = 87%, Kappa = 0.79). The results show that approximately 80% of newly urbanized areas are situated on geomorphologically sensitive units, including inside- and outside-dike floodplains, fluvio-marine plains, paleochannels, and karst terrains, characterized by low elevation and high flood susceptibility. Meanwhile, about 73% of the total inundated area occurs within newly developed urban zones, primarily in western and southwestern Hanoi, where rapid expansion on flood-prone terrain has intensified hazards. The DPSIR analysis highlights rapid population growth, land use change, and inadequate drainage infrastructure as the main pressures driving both the frequency and extent of flooding. To our knowledge, this is the first study integrating geomorphology, Sentinel-1, and DPSIR for Hanoi, thereby providing robust evidence to support sustainable urban planning and climate-resilient development. Full article

Background: Coccidioidomycosis is an endemic fungal infection in the southwestern United States that can present as solitary lung nodules, mimicking malignancy on imaging. Molecular testing, such as PCR, offers rapid diagnosis but its performance in this clinical setting remains unclear. Methods: We conducted a retrospective analysis of patients evaluated for lung nodules at a tertiary care community-based lung nodule clinic in Central California between 2011 and 2025. Coccidioides PCR in patients with proven or probable Coccidioidomycosis was compared to those with biopsy-proven lung cancer. Diagnostic yield of Coccidioides PCR was assessed across biopsy methods and benchmarked against histology and fungal cultures. Results: Among 122 patients with Coccidioidomycosis, PCR demonstrated low sensitivity (range: 20–41%) but high specificity (100%) across all biopsy modalities. Histology and fungal cultures outperformed PCR, detecting additional cases missed by molecular testing. Notably, 9 PCR-negative cases were confirmed on histology, and PCR was only positive in 71.4% of culture-confirmed cases. Conclusion: Coccidioides PCR testing has high specificity but limited sensitivity for diagnosing lung nodules in endemic regions, limiting its utility as a single test. Histology and fungal culture remain essential. Selective use of PCR may enhance diagnostic efficiency and reduce unnecessary costs in regions burdened by Coccidioidomycosis. Full article

This review explores the complex environmental and human health issues facing the Navajo Nation, USA and focuses on arsenic and uranium pollution in vital drinking water sources. Located in the Southwestern United States, with territory comparable to the size of Ireland, these are the homelands of the indigenous Navajo people. Rich in coal, natural gas, and oil, Navajo lands have been a critical target for resource exploitation over the past century. Uranium and arsenic are the two most widespread geogenic contaminants and are also common contaminants associated with mining and other anthropogenic sources in this region. The legacy of uranium mining during the Cold War era on the Navajo Nation has left significant environmental damage to the land and vital drinking water sources in these arid lands. There is an estimated 20 to 30% lack of public water systems in the Navajo Nation, creating a reliance on water hauling for many Navajo families. This reliance often results in the use of potentially harmful contaminated domestic water sources for Navajo families who must gather water from unregulated but available resources. The contamination of drinking water sources poses significant health risks to the Navajo people, who already endure the combined effects of inadequate public infrastructure, a struggling economy, and persistent poverty. There are present and on-going efforts from several key groups and organizations working to address these challenges. However, there is continued need for remediation and mitigation efforts, research, and community involvement to address this critical environmental justice issue and ensure equal access to safe drinking water for the Navajo people. Full article

Indigenous Peoples have developed and stewarded complex knowledge systems that have contributed to thriving societies. With continued threats to Indigenous lifeways, there is increasing need to further protect traditional ecological knowledges (TEK). We carried out a qualitative study to explore Indigenous community perspectives on stewarding and protecting TEK while identifying gaps in community-level protections of TEK. We conducted ten semi-structured interviews in December 2024 and one focus group in January 2025 with Indigenous Peoples in the southwestern United States. Reflexive thematic analysis through open coding was carried out using qualitative software. Six overarching themes were characterized in the interviews, which overlapped with findings from the focus group, including the following: (1) Historical and current barriers impact the sharing of TEK; (2) Preserving our language is necessary for intergenerational transmission of our TEK; (3) Our TEK reveals changes to our Lands; (4) Protecting our Lands and medicines is vital to our health; (5) We must take the time to learn our TEK for future generations; and (6) We need to protect our TEK. Our research highlights the importance of supporting Indigenous communities’ capacities to protect their TEK for personal, community, and environmental well-being. Full article

Many policy recommendations state that children aged 2 to 5 should not spend more than an hour per day in front of a screen; however, these recommendations are challenged as technology use becomes more mobile and accessible to young children. Background/Objectives: The goal of this study is to examine the relationship between children’s and parents’ mobile media use (i.e., smartphones and tablets) and children’s developmental milestones, including their fine motor, gross motor, and personal social skills. Methods: Data for this study comes from two child development centers in the southwestern United States, one serving predominantly middle class families and another serving low-income families (N = 63). Parents completed online surveys regarding their own and their children’s social media use by uploading screenshots of their own and their children’s mobile media device (if applicable) over the last 24 h. Parents identified how many minutes they spent using social media, how many minutes their child spent using social media, and how many minutes their child spent watching television. To capture children’s developmental milestones, parents completed the ages and stages questionnaire (ASQ3), which measures children’s fine motor skills, gross motor skills, and social skills. Results: Correlation and regression analyses revealed that parent mobile media use was positively associated with children’s gross motor and personal social skills (B = 0.38 and 0.32, respectively, p < 0.05; R² = 0.09–0.19) and children’s television viewing was negatively associated with children’s gross motor skills (B = −0.30, p < 0.05). Conclusions: Children’s mobile media may have different consequences for children’s developmental milestones compared to television, and parents’ mobile media use may be more associated with children’s developmental milestones than children’s own use of these devices. Full article

Background/Objectives: Health insurance coverage is critical for children’s health, yet underinsurance remains a significant issue in the United States. This study aims to estimate the prevalence and correlates of childhood underinsurance in southwestern Ohio during a portion of the COVID-19 pandemic. Methods: This is a cross-sectional study of a convenience sample of children, ages 6 months to <18 years, seen in primary care pediatric practices. Recruitment of children’s primary caregivers (PCGs) occurred in practice waiting rooms from June 2021 to April 2023. Respondents completed the Medical Expenses of Children Survey (MEoCS). Index children were considered underinsured if their PCG responded “yes” to any of six questions regarding the inability to pay for a child health clinician’s recommendation despite the child having health insurance. Chi-squared tests and logistic regression were employed in data analysis. Results: 1252 PCGs completed the MEoCS with a response rate of about 90%. 11.3% of index children were underinsured. 41.5% of PCGs raising underinsured children found it harder to access care for their child compared to 3 years ago, while only 9.5% of PCGs raising adequately insured children reported it was harder (p < 0.001). PCGs of underinsured children were more likely to report that COVID-19 had a negative effect on their household income (49.2%) and their child’s school performance (52.0%) and mental health (47.7%) compared to adequately insured children (27.0%, 27.0%, 25.0%; p < 0.001). Conclusions: About 1 in 9 index children were underinsured. Lower parental education and private health insurance were associated with underinsurance across several study cohorts, documenting the stability of these drivers of underinsurance. Full article

Interspecific hybridization in forest trees is common and can have important implications for ecology, evolution, and the conservation of forest habitats. Hybridization often results in greater genetic diversity and opportunities for backcrossing with one or both parents, which may introduce novel genotypes that influence biodiversity and ecosystem processes. However, the extent of hybridization, direction of backcrossing, and overall survival and performance of hybrids is often poorly understood, leading to inaccurate assessments of the role hybrids may play in forest ecology and conservation. Here, we investigate interspecific hybridization and the extent and direction of backcrossing between two species, Populus fremontii (S. Watson) and P. angustifolia (E. James ex Torr.), which are broadly distributed along riparian corridors in the riparian ecosystems of the southwestern United States. Using molecular assays of six putative hybrid zones and a common garden trial we test the following: (1) whether putative hybrids show evidence of genetic intermediacy relative to the parent species; (2) if confirmed hybrids exhibit higher genetic diversity than either parent species; (3) the extent and direction of backcrossing (uni- or bi-directional) within each site; and (4) whether hybrid derivatives show evidence of higher survival and performance in an experimental common garden consisting of both parents and hybrids that were propagated from the six sites. Our results confirm genetic intermediacy in all six sites, but with varying degrees of backcrossing, genetic diversity, and structure. All six locations reveal extensive bidirectional backcrossing to both parent species, a result that contrasts with previous findings, which suggest that backcrossing is predominantly unidirectional between the two species. Results from our common garden trial indicate that hybrids do not have higher survival or out-perform the parent species, suggesting that heterosis may be limited in this system, or that long-term assessments beyond the duration of our field experiment may be required. Results from this study improve our understanding of the frequency of hybridization, and the associated backcrossing in this system, and provide land managers with information on how hybrids may be employed for the long-term preservation of riparian habitats undergoing rapid environmental change. Full article

Generative AI is weaving into the fabric of many human aspects through its transformative power to mimic human-generated content. It is not a mere technology; it functions as a generative virtual assistant, raising concerns about its impact on cognition and critical thinking. This mixed-methods study investigates how GenAI ChatGPT affects critical thinking across cognitive presence (CP) phases. Forty students from a four-year university in the southwestern United States completed a survey; six provided their ChatGPT scripts, and two engaged in semi-structured interviews. Students’ self-reported survey responses suggested that GenAI ChatGPT improved triggering events (M = 3.60), exploration (M = 3.70), and integration (M = 3.60); however, responses remained neutral during the resolution stage. Two modes of interaction were revealed in the analysis of students’ ChatGPT scripts: passive, AI-directed use and collaborative, AI-supported interaction. A resolution gap was identified; nonetheless, the interview results revealed that when GenAI ChatGPT was utilized with guidance, all four stages of cognitive presence were completed, leading to enhanced critical thinking and a reconceptualization of ChatGPT as a more knowledgeable other. This research suggests that the effective use of GenAI in education depends on the quality of human–AI interaction. Future directions must orient toward an integration of GenAI in education that positions human and machine intelligence not as a substitution but as co-participation, opening new epistemic horizons while reconfiguring assessment practices to ensure that human oversight, critical inquiry, and reflective thinking remain at the center of learning. Full article

Despite medical advances having made HIV a survivable condition, HIV persists as the 11th leading cause of death among young Black women. Enhancing the quality of care engagement through beneficial patient–provider relationships can close gaps in retention and adherence, enabling long, healthy lives. Using constructivist grounded theory informed by an established framework for patient-centered care in complex cancer settings and insight from local HIV advocates, this work identifies what provider actions retain women in care and why. Through focus groups and interviews, eleven Black women in the Southwestern United States, an understudied population, express that providers who engage them as co-creators in maintaining good health are more likely to retain them. Concurrently, when women are attuned to their own health care and interpersonal needs, they discern which providers are equally committed to their health based upon observed provider actions. These actions, such as listening attentively, taking time, and paying attention to the whole person, in conjunction with women’s motivation and active involvement, create a reciprocal dynamic that increases the likelihood these women will remain virally suppressed. The ideal relationship is one in which the provider empowers and champions women as drivers of their own care. Full article

The tarnished plant bug, Lygus lineolaris (TPB), (Palisot de Beauvois), and the western tarnished plant bug (WTPB), Lygus hesperus, Knight, are major agricultural pests that cause significant damage to a wide range of crops in the southeastern and southwestern United States. Flonicamid (commercial name: Carbine 50WG) is generally effective against various sap-feeding pests, including both L. hesperus and L. lineolaris. This study evaluated the toxicity of flonicamid on third-instar nymphs and adults of both Lygus species under laboratory conditions. Two bioassay methods were used: spray application to assess both contact and oral toxicity, and dipping to evaluate oral toxicity. Results showed that L. hesperus was significantly more susceptible to flonicamid than L. lineolaris across both bioassay methods. While no significant differences in toxicity were observed between spray and dipping assays, third-instar nymphs exhibited significantly higher sensitivity than adults in both species. The addition of piperonyl butoxide (PBO), a known inhibitor of cytochrome P450-monooxygenases (P450s), significantly enhanced the toxicity of flonicamid, suggesting that P450 enzyme plays a critical role in its detoxification. Sublethal exposure to flonicamid also induced increased P450 activity in both species. These findings provide valuable insights into the differences in susceptibility between L. lineolaris and L. hesperus to flonicamid and indicate that P450-mediated detoxification is critical for flonicamid metabolism. Such insights are valuable for early resistance monitoring and optimizing flonicamid application in integrated pest management programs. Full article

We examine a 25 km resolution climate model dataset to evaluate how regional climate change impacts solar and wind energy under a high-emission scenario. Our study considers the Western Electricity Coordinating Council (WECC) region, which covers the western United States and southwestern Canada, focusing specifically on locations with existing solar and wind infrastructure. First, we conduct a historical model comparison of solar and wind energy capacity factors to highlight model uncertainties across the study area. Using future climate projections, we then assess the seasonal patterns of solar and wind capacity factors for three timeframes: historical, mid-century, and end of century. Additionally, we estimate the frequency of solar and wind resource droughts during these periods for the entire WECC and its five operational subregions, finding that certain subregions are more susceptible to energy droughts due to limited renewable resources. Finally, we present day-ahead capacity factor forecasts to support energy storage planning and provide estimates of offshore wind energy capacity within the WECC. Our results indicate that offshore wind capacity factors are nearly twice as high as onshore values, with less seasonal variation, which suggests that offshore wind could offer a more consistent renewable energy supply in the future. Full article

This study quantitatively evaluates the effects of human activities (HAs) and climate change (CC) on the terrestrial ecosystem carbon cycle, providing a scientific basis for ecosystem management and the formulation of sustainable development policies in urban agglomerations located in arid and ecotone regions. Using the LanXi urban agglomeration in China as a case study, we simulated the spatiotemporal variation of vegetation net primary productivity (NPP) from 2000 to 2023 based on MODIS remote sensing data and the CASA model. Trend analysis and the Hurst index were employed to identify the dynamic trends and persistence of NPP. Furthermore, the Geographical Detector model with optimized parameters, along with nonlinear residual analysis, was employed to investigate the driving mechanisms and relative contributions of HAs and CC to NPP variation. The results indicate that NPP in the LanXi urban agglomeration exhibited a fluctuating upward trend, with an average annual increase of 4.26 gC/m² per year. Spatially, this trend followed a pattern of “higher in the center, lower in the east and west,” with more than 95% of the region showing an increase in NPP. Precipitation, mean annual temperature, evapotranspiration, and land use types were identified as the primary driving factors of NPP change. The interaction among these factors demonstrated a stronger explanatory power through factor coupling. Compared with linear residual analysis, the nonlinear model showed clear advantages, indicating that vegetation NPP in the LanXi urban agglomeration was jointly influenced by HAs and CC. These findings can further act as a basis for resource and environmental research in similar ecotone regions globally, such as Central Asia, the Mediterranean Basin, the southwestern United States, and North Africa. Full article