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Who Bears the Burden? an Assessment of Vulnerability and Resilience to Consecutive Disasters in the Portland Metro Region
No full textClimate-related disasters threaten urban areas worldwide, yet gaps remain in understanding how multiple stressors interact to shape resilience. This study examines exposure, vulnerability, and resilience across three consecutive extreme events in the Portland metro area: the September 2020 wildfire-related air pollution, the February 2021 snowstorm, and the June 2021 heatwave. We used geographically weighted regression and Spearman rank correlation analysis to investigate relationships between hazard impacts, the social vulnerability index (SoVI), Baseline Resilience Indicators for Communities (BRIC), and proximity to community-based organizations (CBOs) in 416 census tracts. Our analysis reveals strong spatial correlations between wildfire-related air pollution, winter storm impacts, and extreme heat exposure. Communities already burdened by poor air quality, freezing precipitation, and urban heat island effects faced heightened cumulative risk. While this varied by neighborhood, racial minorities, migrant workers, non-US citizens, and low-income households were significantly affected. In contrast, affluent communities with lower SoVI scores and higher BRIC values exhibited greater resilience and were less exposed to these hazards. Although CBOs were concentrated in areas with high SoVI, they were insufficient in mitigating disaster impacts. This study underscores the urgent need for multi-hazard resilience planning centered on advancing environmental justice, vulnerability reduction, CBO capacity building, and investment in critical infrastructure in at-risk communities
Impact of Oceanographic Gradients and Marine Heatwaves on the Picophytoplankton Community in the Northern California Current System
No full textThe Northern California Current (NCC) system is a productive coastal ecosystem with a mosaic of temporal and spatial features. The phytoplankton community plays a crucial role in supporting the rich ecosystem and economically important fisheries of the NCC. Our study integrates data across two years (2022-2023) and multiple transects to investigate the community composition of two major phytoplankton groups in the NCC: picocyanobacteria and photosynthetic picoeukaryotes (PPE). The abundances and cell sizes of the phytoplankton were measured using flow cytometry. We found PPE present at similar concentrations in both summer and winter, while picocyanobacteria were much more abundant in the summer than the winter. The relationship between the picocyanobacteria and PPE varied across on- to off-shore transects with different coastal bathymetry. Abundances of both picophytoplankton increased with distance from shore. Cell size also varied along these gradients. Sampling during a marine heatwave in summer 2023 revealed a shift towards smaller picophytoplankton. Overall, these data reveal a dynamic microbial community underlying a productive coastal system, which could inform management decisions and future ecosystem models in the context of climate change and marine heat waves
The 2 Sigma Genus Concept in Mammalogy: Lessons from Lasiurus
No full textSpecies concepts are well established and apply across diverse groups of organisms; however, there is no consensus on what defines higher taxonomic groups. The genus rank is important to taxonomists because it comprises part of the scientific name of an organism. A consistent and biologically meaningful method for determining generic status is needed for taxonomic stability and utility. Lasiurine bats are a group for which there is disagreement on how many genera to recognize. Some authors argue for splitting this group into three genera based on morphology, genetic divergence, and time of divergence; others argue that a single genus should be maintained. Here, we use lasiurines to explore generic-level taxonomy and how it is applied. Genetic divergence levels are compared among sister genera and within genera of vespertilionine bats using Cytochrome b (Cytb) sequences. We used Cytb because it is the most sequenced mitochondrial gene in mammals, but other genes might be more appropriate for a different taxon. Future methods will eventually use complete mitogenomes and genomes. We conclude that lasiurine bats are most appropriately divided into three genera to maintain taxonomic consistency within their subfamily. Since Linnaeus, the quarter millennium of progress in the science of mammalogy has provided a binomial nomenclatural basis from which can be extracted an acceptable range of genetic diversity upon which to establish generic level taxonomy. We offer a biologically meaningful operational definition of the genus, which we call the 2 Sigma Genus Concept, based on genetic divergence between a genus and its sister genus or lineage and compared to the divergence between sister pairs of established genera in the same higher taxonomic category. Our method is phylogenetic; sister genera are based on the best phylogeny for the higher taxonomic category. Genera must be monophyletic and differ from their closest relatives by not more than two standard deviations above or below the mean value of genetic distance for the larger taxonomic group in which they are contained. There should be genetic-based characters (e.g., morphology, protein structure, behavior) that are diagnostic for each genus. Our method is novel in that it uses the statistical distribution of sister divergences within a higher category to guide the allocation of generic status to monophyletic lineages. Within Vespertilioninae, the mean genetic distance between sister genera is 20.68% ± 3.89% (K2P) for the Cytb gene. Therefore, a proposed new genus should have \u3e12.90% genetic distance to its sister genus. Genera that are \u3e 2 standard deviations above the mean (\u3e28.46%) are candidates to be recognized as a higher category such as tribe or subfamily. The sister-genus divergence for the monophyletic lineage that includes all lasiurine bats is 31.14% ± 1.64% which qualifies it as a higher category (i.e., tribe), and the sister-genus divergences of the three monophyletic lineages within Lasiurini (i.e., red, yellow and hoary bats) are 21.77% and 22.91% which qualifies them for genera. We show the applicability of the method beyond Vespertilioninae by providing a case study where we apply it in a distantly related subfamily of bats
Physical and Mental Health of Behavioural Health Certified Peer Specialists in Four US States
No full textBackground:
Little is known about the health and healthcare needs of the behavioural health peer specialist workforce in the USA. This study explored the physical and mental health-related quality of life (QOL) of a US multistate cohort of certified peer specialists, and factors associated with health-related work absences among those employed in peer specialist positions.
Methods:
Data come from 419 participants surveyed 18 months after state certification as part of a 2-year longitudinal cohort study of peer specialists in four US states. Measures included the Veterans RAND 12 Item Health Survey, the Epidemic-Pandemic Impacts Inventory and items from the National Health & Nutrition Examination Survey and Medical Expenditure Panel Survey. Multivariable hierarchical regression models predicted physical and mental health-related QOL and occurrence of work absences due to health.Results High rates (60%) of multiple physical health conditions characterise both those working in peer support positions and those not employed. Better physical health-related QOL was associated with younger age, not having multiple physical health conditions, not experiencing cost as a barrier to healthcare and not being enrolled in Medicaid or Medicare. Better mental health-related QOL was associated with older age, being Black/African-American, employment in peer support positions, moderate exercise, having a usual source of medical care and cost not being a barrier to care. Among those employed as peer specialists, health-related work absences were associated with physical and mental health QOL and other factors.
Conclusions:
Certified peer specialists have high rates of physical comorbidities, and this affects their mental and physical health-related QOL and likelihood of working in peer support positions. Factors such as cost, having a regular source of healthcare, insurance coverage and demographic features are also associated with their QOL. These findings can inform efforts to attract and retain certified peer specialists in the behavioural health workforce
Leveraging Social Capital for Value Creation in Public Procurement: the Role of Strategic Purchasing Integration
No full textPurpose Although the integration of the purchasing function within strategic decision-making has been extensively studied in the context of the private sector, its significance for the effective functioning of public procurement (PP) remains underexplored. Effective PP is critical for suppliers, users of public services and society at large. This study investigates how the strategic integration of PP influences operational, environmental and innovative value creation by developing social capital in buyer–supplier relationships. Design/methodology/approach This study empirically examined how strategic purchasing integration contributes to the development of social capital in buyer–supplier relationships, which in turn affects value creation. It utilizes survey data from PP experts in Finland, complemented by a series of post-survey interviews designed to gain deeper insights, especially into some less-expected findings. Findings Applying social capital theory, we discovered that the strategic integration of purchasing is crucial for effectively developing social capital within buyer–supplier relationships. Interestingly, we revealed that different types of value creation require varying combinations of social capital. The post-survey interviews suggested that these differences likely arise from the limited capabilities of public organizations or perceived barriers imposed by legislation. Originality/value This study complements findings from the private sector showing that purchasing integration and social capital are relevant for value creation. It also reveals the unique public sector dynamics that limit the effectiveness of relational and cognitive capital in realizing operational and environmental value
Transfer Learning-Based Multi-Sensor Approach for Predicting Keyhole Depth in Laser Welding of 780DP Steel
No full textPenetration depth is a critical factor determining joint strength in butt welding; however, it is difficult to monitor in keyhole-mode laser welding due to the dynamic nature of the keyhole. Recently, optical coherence tomography (OCT) has been introduced for real-time keyhole depth measurement, though accurate results require meticulous calibration. In this study, deep learning-based models were developed to estimate penetration depth in laser welding of 780 dual-phase (DP) steel. The models utilized coaxial weld pool images and spectrometer signals as inputs, with OCT signals serving as the output reference. Both uni-sensor models (based on coaxial pool images) and multi-sensor models (incorporating spectrometer data) were developed using transfer learning techniques based on pre-trained convolutional neural network (CNN) architectures including MobileNetV2, ResNet50V2, EfficientNetB3, and Xception. The coefficients of determination values (R) of the uni-sensor CNN transfer learning models without fine-tuning ranged from 0.502 to 0.681, and the mean absolute errors (MAEs) ranged from 0.152 mm to 0.196 mm. In the fine-tuning models, R decreased by more than 17%, and MAE increased by more than 11% compared to the previous models without fine-tuning. In addition, in the multi-sensor model, R ranged from 0.900 to 0.956, and MAE ranged from 0.058 mm to 0.086 mm, showing better performance than uni-sensor CNN transfer learning models. This study demonstrated the potential of using CNN transfer learning models for predicting penetration depth in laser welding of 780DP steel
(de)centralized Water Futures: Key Dimensions of Infrastructure, Governance, and Operations
No full textWater system centralization and decentralization have variously been promoted as key to achieving household water security and Sustainable Development Goal 6.1. We argue that the lack of specificity with which scholars and practitioners use the terms centralization and decentralization limits our understanding of different water system configurations and their impacts. In this Primer, we provide a framework for thinking about levels of (de)centralization across three linked system dimensions: infrastructure, governance, and operations and maintenance. We encourage those analyzing water systems to characterize (de)centralization with respect to these multiple dimensions, as well as the system\u27s broader political-economic and hydro-climatic contexts. Emphasizing the importance of delineating the scale of analysis, we highlight distinct system configurations and the prevalence of hybridity. Increased specificity about dimensions and scale can clarify how the character of, or changes to, a given system impact users, which is critical to assessing their implications for water security, sustainability, and equity. We conclude with recommendations for future research to analyze the opportunities and challenges associated with different water system configurations. This article is categorized under: Human Water \u3e Water Governance
Discourse Analysis of Partner-focus in Intimate Partner Violence
No full textIntimate partner violence (IPV) involves behaviors that harm or threaten to harm an intimate partner; but more importantly, it involves the production of power and control in an intimate relationship that threatens a partner\u27s liberty and wellbeing. As a wicked problem, IPV is challenging to unpack without reducing the complexities that give it its power. This study seeks to explore the complex nature of how abusive men\u27s focus on their partner functions as a mechanism of abuse. To develop the concept of other-focus I draw on constructs of coercive control, power, and dominance. To investigate partner-focus, I conducted a discourse analysis of abusive men\u27s (n=14) narratives gathered through semi-structured interviews. Participants were asked to describe their relationship, conflict in their relationship, and situations where conflict escalated to aggression. Analysis explored how participants centered their partners and how this functioned in the discourse. Findings demonstrate how discourse was used to direct attention and foreground their partner in ways that diminished her character and elevated the identity of the participant, while disavowing the participant\u27s role in relationship conflict. These findings are consistent with the use of coercive control, power, and dominance in abusive relationships found in the literature, but extends this understanding by explicating the dynamic processes of discourse and the use of attentional focus in producing harmful effects associated with IPV
Pressure and Force Dynamics in Artificial Muscle Actuators: A State-Space and Optimization-Based Approach
No full textThis two-part investigation explores the dynamic behavior of braided pneumatic actuators (BPAs) under bio-inspired pulse modulation, with the aim of improving their biomimetic force output and control. The first study examines the effect of pulse length and inter-pulse timing on BPA performance, revealing that force output is highly sensitive to the temporal structure of input pulses mirroring biological muscle behavior. Using dual-pulse actuation schemes, the results demonstrate that force responses exceed the additive contributions of individual pulses, with peak amplification occurring consistently at a 27 ms inter-pulse gap. Shorter pulse lengths (10–20 ms) yielded the highest normalized force increases, up to 3.55 times greater than a single pulse, highlighting the nonlinear summation properties of BPAs under pulse modulation.
Building on these findings, the second study develops a state-space model to predict pressure dynamics based on valve actuation inputs, incorporating three spring-damper-mass systems to represent the distributed air volume and its mechanical effects. Parameters were optimized via Particle Swarm Optimization (PSO), achieving predictive pressure errors between 5-16% across three muscle lengths (600 mm, 310 mm, and 140 mm). A nonlinear model was then used to correlate pressure with force output, with fitting errors below 3%. Key insights indicate that longer BPAs yield higher peak forces and smoother decay profiles due to their larger internal volumes, while shorter BPAs respond more rapidly but require higher pulse frequencies to sustain force output.
Together, these works establish a foundation for the real-time control and simulation of BPAs using biologically inspired actuation patterns. The combination of empirical pulse modulation data and validated dynamic models enables more adaptable and efficient actuator control strategies, applicable to soft robotics and human-assistive devices
The Call of Cucurrucucú
No full textThis is a site of geologic excavation; where charged voices like porous monoliths and forked-tongue shapeshifters call out in fragmented polyphony. What lies broken or misshapen, what can be pieced back together.
What is purity when the body that is being inherited is drowning in murky waters