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Abalone and Seaweed Co-culture: Growth and Shell Biomineralization of an Iconic California Gastropod
Get PDFClimate change threatens shellfish aquaculture worldwide, with ocean acidification (OA) accelerating shell dissolution and reducing calcification, hindering growth. This study addressed the negative impacts of OA on juvenile red abalone (Haliotis rufescens), a life stage that is particularly susceptible to climate stressors, and the ability of the red seaweed, dulse (Devaleraea mollis), to mitigate these effects. I tested the hypothesis that Integrated Multi-Trophic Aquaculture (IMTA), with abalone and seaweed grown in co-culture, can raise seawater pH through photosynthesis to yield more favorable conditions for abalone growth and shell construction. A 5-month experiment was conducted to determine the benefits of IMTA on abalone growth, shell composition, and morphology under simulated ocean acidification conditions. In each tank, 620 abalone were raised in either High (8.1 ± 0.3), Ambient (7.9 ± 0.2), Medium (7.8 ± 0.3), or Low pH (7.6 ± 0.2). Abalone raised in High and Ambient pH treatments exhibited greater shell length, weight, area, and condition compared to those raised in medium and low pH treatments. Shell analyses indicated that these growth differences translate into differences in physical and chemical properties, with shells from the high and ambient pH treatments containing higher levels of Mg2+ and being more resistant to fracturing. These findings indicate that IMTA could shepherd abalone through the susceptible juvenile stage, increasing resilience of abalone aquaculture even within the context of future climate change
Evaluation of WindNinja Simulations in Canyons and Complex Terrain
No full textThis study describes a validation of the surface wind model WindNinja conducted over different types of complex terrain. WindNinja is one of many software tools first responders use to better understand wind flow over such terrain. One approach to receive a higher resolution wind field to account for local terrain effects is to downscale numerical weather prediction model output with the help of WindNinja. 2 km resolution Weather Research and Forecasting model (WRF) output was used as input for our WindNinja simulations. We tested the surface wind model for two case sites in California characterized by canyons of different terrain complexity. Simulations were conducted with different initialization methods and numerical solvers within WindNinja to see how the model performs using different setups. The first simulations were conducted by initializing the model from a singular point. Further simulations were initialized using a spatial method with explicit input values over the whole modeling domain. WindNinja was also tested during a wind event to evaluate its performance during critical fire weather scenarios. The simulation results were then compared to WRF’s model output to see if WindNinja could improve upon the mesoscale model’s forecast in a canyon setting. Statistical error metrics were calculated to compare the model output to the observations and thus validate the performance of both WindNinja and WRF at several stations for the two case sites. WindNinja performed only marginally better than WRF over simpler terrain. WRF performed best in complex terrain with steep canyons compared to WindNinja, which struggled with increased wind speeds at peaks and ridges
The Role of Attention in the Perception of Non-native Accented Speech
No full textListeners rapidly adapt to variation in speech through perceptual learning. The present study examined the extent to which perceptual learning of non-native accented speech varies as a function of task-directed shifts in attention. Listeners completed an exposure phase during which they heard English sentences produced by Spanish accented talkers while completing tasks requiring different levels of attention to the target stimuli. Across conditions, listeners completed either alternating transcription and talker identification tasks (Task-Relevant condition), a symbol-to-number matching task (Task-Irrelevant condition), or the same task as in the Task-Relevant condition but with native English sentences (Control). At test, listeners transcribed novel sentences spoken by novel Spanish-accented talkers. The trajectory of perceptual learning differed across conditions such that during the first half of test trials, transcription accuracy was reliably higher for the task-irrelevant versus the control condition. This suggests that, especially for first encounters with novel voices, passive exposure to a non-native accent can potentially yield learning of accent-general characteristics that transfers to novel voices of the same accent
The Second Annual Blockchain Tax Conference on January 24, 2025: Ensuring Widespread Implementation of the Crypto-Asset Reporting Framework (CARF)
Get PDFDiscovery of Two Ultra-diffuse Galaxies with Unusually Bright Globular Cluster Luminosity Functions via a Mark-dependently Thinned Point Process (MATHPOP)
Get PDFWe present MArk-dependently THinned POint Process (Mathpop), a novel method to infer the globular cluster (GC) counts in ultra-diffuse galaxies (UDGs) and low-surface brightness galaxies (LSBGs). Many known UDGs have a surprisingly high ratio of GC number to surface brightness. However, standard methods to infer GC counts in UDGs face various challenges, such as photometric measurement uncertainties, GC membership uncertainties, and assumptions about the GC luminosity functions (GCLFs). Mathpop tackles these challenges using the mark-dependent thinned point process, enabling joint inference of the spatial and magnitude distributions of GCs. In doing so, Mathpop allows us to infer and quantify the uncertainties in both GC counts and GCLFs with minimal assumptions. As a precursor to Mathpop, we also address the data uncertainties coming from the selection process of GC candidates: we obtain probabilistic GC candidates instead of the traditional binary classification based on the color-magnitude diagram. We apply Mathpop to 40 LSBGs in the Perseus cluster using GC catalogs from a Hubble Space Telescope imaging program. We then compare our results to those from an independent study using the standard method. We further calibrate and validate our approach through extensive simulations. Our approach reveals two LSBGs having GCLF turnover points much brighter than the canonical value with Bayes’ factor being ∼4.5 and ∼2.5, respectively. An additional crude maximum-likelihood estimation and simulation study show that their GCLF TO points are approximately 0.9 mag and 1.1 mag brighter than the canonical value, with p-values of ∼10−8 and ∼10−5, respectively
Reinforcement learning-based dynamic field exploration and reconstruction using multi-robot systems for environmental monitoring
Get PDFIn the realm of real-time environmental monitoring and hazard detection, multi-robot systems present a promising solution for exploring and mapping dynamic fields, particularly in scenarios where human intervention poses safety risks. This research introduces a strategy for path planning and control of a group of mobile sensing robots to efficiently explore and reconstruct a dynamic field consisting of multiple non-overlapping diffusion sources. Our approach integrates a reinforcement learning-based path planning algorithm to guide the multi-robot formation in identifying diffusion sources, with a clustering-based method for destination selection once a new source is detected, to enhance coverage and accelerate exploration in unknown environments. Simulation results and real-world laboratory experiments demonstrate the effectiveness of our approach in exploring and reconstructing dynamic fields. This study advances the field of multi-robot systems in environmental monitoring and has practical implications for rescue missions and field explorations
Health Care Professionals’ Perspectives on Technology Use in Urinary Care: Cross-Sectional Survey-Based Study
Get PDFBackground: Urinary issues pose a significant burden on health care systems, necessitating innovative solutions to enhance patient care and alleviate the provider burden. Objective: The objective of this study was to explore health care professionals’ perceptions of urinary issues and assess their acceptance and readiness to adopt wearable and remote technologies for managing these conditions. The study aimed to identify the attributes and barriers influencing technology integration in clinical practice, using established theoretical frameworks, such as the Health Belief Model (HBM) and the Technology Acceptance Model (TAM). Methods: A cross-sectional survey-based study was conducted. A structured survey questionnaire was administered online to a sample of 256 health care professionals recruited through social media and personal networks. The survey included both closed- and open-ended questions to gather data. Quantitative data were analyzed using descriptive statistics, Pearson correlation, and multiple regression. Results: Quantitative analysis revealed strong correlations between belief agreement and factors such as health literacy (r=0.591, P\u3c.001), the perceived burden (r=0.628, P\u3c.001), device attributes (r=0.650, P\u3c.001), and support services (r=0.622, P\u3c.001). Multiple regression analysis identified that the perceived burden (β=.284, P=.01), device attributes (β=.371, P\u3c.001), and integrating technology (β=.312, P\u3c.001) are positively associated. The survey demonstrated strong internal consistency, with Cronbach α=.85, indicating high reliability in measuring health care professionals’ perceptions of technology adoption. Conclusions: Health care professionals’ acceptance of technology in managing urinary issues is influenced by factors such as the perceived burden, device attributes, and the ease of integrating technology into existing workflows. Addressing barriers to technology adoption, providing comprehensive training and support, and prioritizing user-centered design are crucial for successful technology integration. Future research should focus on longitudinal studies and explore the perspectives of patients and other stakeholders to gain a more holistic understanding of technology integration in urological care
Collective liberation through critical pedagogy
Get PDFThe collective liberation of queer and trans people—which is inherently tied to the liberation of those oppressed by white supremacy and racism, ableism, classism, ageism, and other asymmetrical power distributions—is possible when we develop critical consciousness through critical pedagogy. As young people develop an awareness of the contradictions and falsehoods they are taught (e.g., the myth of meritocracy), they begin to work to change their environments and offer resistance to the structures that inequitably shape their world. The vast majority of research on queer and trans adolescents, though, has been shaped by dominant, deficit-based views of queerness that presuppose that queer and trans youth are always already only victims who are damaged by their society. This leads most research to rely on unspoken assumptions that queer and trans youth are passive victims whose most salient features are the presence, absence, or severity of mental health concerns. Critical pedagogy provides a framework for researchers, educators, and adolescents themselves to better understand the power that queer and trans youth cultivate through their adolescence, without ignoring the harms that heterosexist and cissexist environments enact on them. Indeed, critical pedagogy provides a fruitful avenue for researchers to examine the ways that queer and trans adolescents experience discovery, joy, and freedom as they work to change the broken world they have inherited
Why do some ultra diffuse Galaxies have rich globular cluster systems?
Get PDFSome ultra diffuse galaxies (UDGs) reveal many more globular clusters (GCs) than classical dwarf galaxies of the same stellar mass. These UDGs, with a mass in their GC system () approaching 10 per cent of their host galaxy stellar mass (), are also inferred to have high halo mass to stellar mass ratios (). They have been dubbed Failed Galaxies. It is unknown what role high GC formation efficiencies and/or low destruction rates play in determining the high ratios of some UDGs. Here we present a simple model, which is informed by recent JWST observations of lensed galaxies and by a simulation in the literature of GC mass loss and tidal disruption in dwarf galaxies. With this simple model, we aim to constrain the effects of GC efficiency/destruction on the observed GC richness of UDGs and their variation with the integrated stellar populations of UDGs. We assume no ongoing star formation (i.e. quenching at early times) and that the disrupted GCs contribute their stars to those of the host galaxy. We find that UDGs, with high ratios today, are most likely the result of very high GC formation efficiencies combined with modest rates of GC destruction. The current data loosely follow the model that ranges from the mean stellar population of classical dwarfs to that of metal-poor GCs as increases. As more data becomes available for UDGs, our simple model can be refined and tested further