Browse Articles
Discover research articles across all indexed journals
Pore network modeling of water and gas transport characteristics in synthetic porous media
The flow characteristics of water and gas are closely linked to pore structure of porous media, which is of critical importance across various scientific and industrial fields. In this study, synthetic porous media with varying grain sizes and porosity were generated, and their corresponding pore structures were characterized using pore network modeling. Furthermore, the intrinsic permeability, water retention curve, water-gas relative permeability and relative gas diffusivity of the synthetic porous media were simulated via pore network modeling. The results demonstrate that the pore networks extracted from images can effectively distinguish pore structural characteristics. Specifically, the mean pore diameter, throat diameter, and throat length were larger in coarse-grained media compared to fine-grained media of the same porosity. In contrast, fine-grained media exhibited higher values for pore number, throat number, and coordination number. Additionally, the distributions of pore diameter, throat diameter, throat length and coordination were found to follow a lognormal distribution. Porous media with coarse grains and larger porosity exhibit greater intrinsic permeability and relative gas diffusivity compared to media composed of finer grains or lower porosity. The water-retention curves were fitting by van Genuchten model, revealing an exponential relationship between parameter α and throat diameter (or pore diameter). But the parameter n did not show a clear trend across various synthetic porous media, which is attributed to the relatively narrow range of pore size distribution. Similarly, for water-gas relative permeability, the critical water saturation did not vary significantly across different porous media. A strong correlation was observed among the pore structural parameters, irrespective of grain shape and size. Both intrinsic permeability and relative gas diffusivity exhibited a power-law relation with the porosity as well as with pore or throat radius. Moreover, the relationship between intrinsic permeability and relative gas diffusivity can be expressed as k = 166.51( D p / D 0 ) 0.98 , which provides a direct means of estimating relative gas diffusion from intrinsic permeability directly.
Analysis of nicotine, tar, carbon monoxide, total particulate matter, water, benzo[a]pyrene, and humectants in cigarettes and bidis from India and Myanmar
Abstract Tobacco use poses a major public health challenge in the World Health Organization’s South-East Asia Region, where it contributes to approximately 2.3 million deaths each year. In 2020 alone, tobacco smoking was responsible for around 1.6 million of these deaths. The region faces a dual burden of high prevalence of both smoking and smokeless tobacco use, underscoring the urgent need for strengthened tobacco control measures. The toxic substances found in the emissions of smoked tobacco products are inadequately researched. This study presents primary scientific information on levels of nicotine, water, and benzo[a]pyrene (BaP) in mainstream smoke deliveries from popular cigarettes from India and Myanmar, and bidis from India; additionally, flavours and humectants were tested in fillers. Globally accepted methods from the World Health Organization’s Tobacco Laboratory Network (TobLabNet), the Centers for Disease Control and Prevention (CDC), and the Cooperation Centre for Scientific Research Relative to Tobacco (CORESTA) were used. When comparing Indian and Myanmar cigarettes, we discovered that nicotine and carbon monoxide (CO) levels in Myanmar cigarettes were slightly higher than those in Indian ones, though the difference was not statistically significant. Water, tar, and total particulate matter (TPM) also exhibited no statistically significant variations. Significantly higher (p = 0.008) concentrations of BaP, ranging from 8.02 to 14.90 ng/cigarette (median, 9.95 ng/cigarette), were observed in Myanmar-origin cigarettes, indicating increased exposure risks for users. Among humectants, only propylene glycol showed significant variation ( p = 0.023). Compared with Indian cigarettes, bidis showed significantly higher nicotine and CO ( p = 0.023), as well as water and TPM ( p = 0.008). When bidis were compared with cigarettes from both countries, nicotine (p = 0.041), water, and TPM differed significantly (both p < 0.001). The intended flavours were not detected in the mainstream smoke of the cigarettes and bidis examined. The findings of this study can be leveraged to enhance public health by identifying harmful chemicals that exceed established limits and potentially motivating manufacturers to produce less harmful products by conforming to toxicant emission standards.
Developing and validating a holistic welfare assessment tool for zoo-housed great apes: Integrating resource-based measures with behavioural ecology insights
Assessing the welfare of zoo-housed great apes is essential to ensure high standards of care, maintain zoos’ ethical and educational credibility, and support their conservation roles. However, welfare assessment remains challenging due to the complex cognitive, social, and behavioural needs of great apes and the limitations of existing evaluation methods. Many zoos rely on resource-based measures, which are easy to collect but lack the specificity needed to assess welfare accurately. In this study, we developed and tested a new standardized, evidence-based approach that integrated resource-based data with ecological and behavioural insights. This Ape Welfare Assessment, Resources and Ecology (AWARE) Tool was developed through collaboration with the Great Ape Welfare group (GAWg) and aimed to: (1) collect a holistic suite of resource and husbandry data that measures the constraints on the apes opportunities to express key naturalistic behaviours, (2) contextualize results within species-specific research on wild and captive great ape behavioural ecology and welfare, and (3) extend beyond existing zoo accreditation standards to support zoos aspirations for higher levels of welfare. Using data from zoo-housed chimpanzees, we tested whether this approach enhanced the validity of resource-based welfare assessments. Results demonstrate that the approach strengthens welfare evaluations and provides a more nuanced understanding of captive great ape wellbeing. We also propose a new validation framework for holistic welfare assessment tools such as this, where validating all individual indicators is neither feasible nor informative. Ultimately, we aim for the AWARE Tool to serve as a web-based resource for independent zoo use and formal welfare assessments. Future research will expand its application to gorillas and orangutans. This study represents a major leap towards establishing robust, species-informed and validated welfare assessment methodologies for zoo-housed great apes.
Machine learning prediction of food addiction in university students using demographic, anthropometric and personality traits
Aligning cardiac monitoring with American Heart Association Guidelines: Impact on utilization, hemodynamic monitoring, and outcomes
Background Overuse of continuous cardiac monitoring can lead to poor patient experience, increased costs, and decreased efficiency. Because significant variation in continuous cardiac monitoring ordering exists, implementation strategies that promote care in alignment with practice standards and an examination of use cases that fall outside of standards are needed. The purpose of this study, therefore, was to evaluate if implementation of American Heart Association (AHA) practice standards on continuous cardiac monitoring could reduce utilization without jeopardizing patient safety. Methods We conducted a prospective pre-post study including a 2 year prospectively collected baseline against a 10-month post intervention period within a 10-hospital health system. An electronic health record (EHR) order set was implemented to align care with AHA continuous cardiac monitoring practice standards. We compared continuous cardiac monitoring utilization, adherence to standards, as well as clinical outcomes including mortality and length of stay. Finally, we investigated the rate and impact of hemodynamically significant events (hypotension, bradycardia, and tachycardia) before and after the intervention. Results We compared 117,814 hospitalizations pre-implementation against 49,006 post implementation finding significant reductions in total telemetry use, and no significant change in outcomes. Overall, patients with telemetry use outside of standards had higher mortality, longer length of stay, and higher readmission rates. The intervention was associated with a higher rate of hypotensive events which occurred off cardiac monitoring. This was not associated with worse outcomes. Conclusions An EHR tool to align care with continuous cardiac monitoring practice standards safely reduced overall continuous cardiac monitoring utilization. Use outside of practice standards persisted and was primarily focused on monitoring for potential hemodynamic instability. We found no evidence that continuous cardiac monitoring was associated with improved outcomes in unstable patients. Continuous cardiac monitoring for potentially unstable patients can likely be replaced for non-cardiac indications with continuous heart rate monitoring.
Machine learning-based estimation and optimization of phoenix Dactylifera Seed Powder reinforced vinyl ester bio-composites
Statistical analysis of winning percentages in Japanese professional baseball using the Wins above Replacement indicator
This study examines a previously unexplored concept in the field of sabermetrics. By employing a novel correction that accounts for player position differences, it investigates the impact of the designated hitter (DH) system on team wins in Japanese professional baseball using the Wins above Replacement metric. We applied this innovative correction to Pacific League data from 2014 to 2023, accounting for positional differences in player contributions. Our results indicate no significant difference in the correlation coefficients between team average wins above replacement (WAR) and winning percentage under conditions including and excluding the DH position, suggesting that the DH system does not substantially impact team performance. These findings offer a nuanced understanding of the DH system’s role in baseball strategy and team dynamics.
Effect of calcined street sweeping sediment on the mechanical and rheological properties of fly ash–slag geopolymers
Developing a machine learning model to map new-build gentrification: A mixed-methods approach
New-build gentrification, a type of gentrification which is connected to newly built development, has radically transformed the appearance of neighborhoods across the United States. However, the literature is lacking discussion on the built component of the new-build gentrification process, which can lead to inaccurate maps and projections of gentrification trends. Recent advancements in machine learning (ML), specifically computer vision models that apply neural network “deep mapping” algorithms, have found application in the research for their ability to track changes in urban streetscapes. In our research, we trained machine learning models to identify new-build development with architectural traits that reflect visual cues of gentrification according to local residents. With Philadelphia as our study area, we drew on the insight of community-based focus groups to identify characteristics that denote new-build gentrification for the city. We compared our audit of new-build gentrification development with municipal permit License and Inspections (L&I) data, using Kernel Density Estimate (KDE) maps to visualize the spatial trends of both datasets. Our final fine-tuned ResNet-50 model achieved an 84.0% test accuracy and an 84.0% Area Under the Curve (AUC) score. Our research contributes a novel mixed-methods approach that integrates community input with Artificial Intelligence (AI) to identify locally-specific gentrification traits.
Integrator dynamics in the cortico-basal ganglia loop for flexible motor timing
Abstract Flexible control of motor timing is crucial for behaviour 1–4 . Before volitional movement begins, the frontal cortex and striatum exhibit ramping spiking activity, with variable ramp slopes anticipating movement onsets 5–12 . This activity in the cortico-basal ganglia loop may function as an adjustable ‘timer,’ triggering actions at the desired timing. However, because the frontal cortex and striatum share similar ramping dynamics and are both necessary for timing behaviours, distinguishing their individual roles in this timer function remains challenging. Here, to address this, we conducted perturbation experiments combined with multi-regional electrophysiology in mice performing a flexible lick-timing task. Following transient silencing of the frontal cortex, cortical and striatal activity swiftly returned to pre-silencing levels and resumed ramping, leading to a shift in lick timing close to the silencing duration. Conversely, briefly inhibiting the striatum caused a gradual decrease in ramping activity in both regions, with ramping resuming from post-inhibition levels, shifting lick timing beyond the inhibition duration. Thus, inhibiting the frontal cortex and striatum effectively paused and rewound the timer, respectively. These findings are consistent with a model in which the striatum is part of a network that temporally integrates input from the frontal cortex and generates ramping activity that regulates motor timing.