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The utility of molten chloride salts in concentrating solar power (CSP) is dependent on the ability to maintain low corrosive impurities. Without proper purification, the corrosion rates of containment alloys exceed the industry standard of corrosion—under 20 μm/year. An extensive body of literature focuses on the initial purification stage of molten chloride salts. However, occurrences such as maintenance, leaks, and so forth expose the salt to the atmosphere and reintroduce impurities. Therefore, it is critical to develop a purification strategy that can control impurity levels during CSP plant operation. Here we present the design and fabrication of a purification vessel to continuously remove impurities out of flowing molten salt.

Abstract Since the early 2000s, sea ice has experienced an increased rate of decline in thickness, extent and age. This new regime, coined the ‘New Arctic’, is accompanied by a reshuffling of energy flows at the surface. Understanding of the magnitude and nature of this reshuffling and the feedbacks therein remains limited. A novel database is presented that combines satellite observations, model output, and reanalysis data with sea ice parcel drift tracks in a Lagrangian framework. This dataset consists of daily time series of sea ice parcel locations, sea ice and snow conditions, and atmospheric states, including remotely sensed surface energy budget terms. Additionally, flags indicate when sea ice parcels travel within cyclones, recording cyclone intensity and distance from the cyclone center. The quality of the ice parcel database was evaluated by comparison with sea ice mass balance buoys and correlations are high, which highlights the reliability of this database in capturing the seasonal changes and evolution of sea ice. This database has multiple applications for the scientific community; it can be used to study the processes that influence individual sea ice parcel time series, or to explore generalized summary statistics and trends across the Arctic.

This paper offers a novel understanding of collective responsibility for AI outcomes that can help resolve the “problem of many hands” and “responsibility gaps” when it comes to AI failure, especially in the context of lethal autonomous weapon systems.

Abstract Brains demonstrate varying spatial scales of nested hierarchical clustering. Identifying the brain’s neuronal cluster size to be presented as nodes in a network computation is critical to both neuroscience and artificial intelligence, as these define the cognitive blocks capable of building intelligent computation. Experiments support various forms and sizes of neural clustering, from handfuls of dendrites to thousands of neurons, and hint at their behavior. Here, we use computational simulations with a brain-derived fMRI network to show that not only do brain networks remain structurally self-similar across scales but also neuron-like signal integration functionality (“integrate and fire”) is preserved at particular clustering scales. As such, we propose a coarse-graining of neuronal networks to ensemble-nodes, with multiple spikes making up its ensemble-spike and time re-scaling factor defining its ensemble-time step. This fractal-like spatiotemporal property, observed in both structure and function, permits strategic choice in bridging across experimental scales for computational modeling while also suggesting regulatory constraints on developmental and evolutionary “growth spurts” in brain size, as per punctuated equilibrium theories in evolutionary biology.

We show sharp Vizing-type inequalities for eternal domination. Namely, we prove that for any graphs G and H, where is the eternal domination function, α is the independence number, and is the strong product of graphs. This addresses a question of Klostermeyer and Mynhardt. We also show some families of graphs attaining the strict inequality where is the Cartesian product. For the eviction model of eternal domination, we show a sharp upper bound for

The spatial pattern and global mean values of warming differ between different climate models, an issue that needs to be better understood in order to obtain reliable regional projections. Here, the authors show that ice-albedo and water vapor feedbacks are the key processes that are responsible for this inter-model spread.

We analyze retrospectively/prospectively the transient variations of six different physical parameters in the atmosphere/ionosphere during the M7.8 and M7.3 earthquakes in Nepal, namely: 1) outgoing longwave radiation (OLR) at the top of the atmosphere (TOA); 2) GPS/TEC; 3) the very-low-frequency (VLF/LF) signals at the receiving stations in Bishkek (Kyrgyzstan) and Varanasi (India); 4) Radon observations; 5) Atmospheric chemical potential from assimilation models; and; 6) Air Temperature from NOAA ground stations. We found that in mid-March 2015, there was a rapid increase in the radiation from the atmosphere observed by satellites. This anomaly was located close to the future M7.8 epicenter and reached a maximum on April 21–22. The GPS/TEC data analysis indicated an increase and variation in electron density, reaching a maximum value during April 22–24. A strong negative TEC anomaly in the crest of EIA (Equatorial Ionospheric Anomaly) occurred on April 21, and a strong positive anomaly was recorded on April 24, 2015. The behavior of VLF-LF waves along NWC-Bishkek and JJY-Varanasi paths has shown abnormal behavior during April 21–23, several days before the first, stronger earthquake. Our continuous satellite OLR analysis revealed this new strong anomaly on May 3, which was why we anticipated another major event in the area. On May 12, 2015, an M7.3 earthquake occurred. Our results show coherence between the appearance of these pre-earthquake transient’s effects in the atmosphere and ionosphere (with a short time-lag, from hours up to a few days) and the occurrence of the 2015 M7.8 and M7.3 events. The spatial characteristics of the pre-earthquake anomalies were associated with a large area but inside the preparation region estimated by Dobrovolsky-Bowman. The pre-earthquake nature of the signals in the atmosphere and ionosphere was revealed by simultaneous analysis of satellite, GPS/TEC, and VLF/LF and suggest that they follow a general temporal-spatial evolution pattern that has been seen in other large earthquakes worldwide.

Background: Mental imagery abnormalities feature across affective disorders including bipolar disorder (BD) and unipolar depression (UD). Maladaptive emotional imagery has been proposed as a maintenance factor for affective symptomatology and a target for mechanism-driven psychological treatment developments. Where imagery abnormalities feature beyond acute affective episodes, further opportunities for innovation arise beyond treatments, such as for tertiary/relapse prevention (e.g., in remitted individuals) or primary prevention (e.g., in non-affected but at-risk individuals). The aim of our study was to investigate for the first time the presence of possible mental imagery abnormalities in affected individuals in remission and at-risk individuals for affective disorders using a familial risk design.Methods: A population-based cohort of monozygotic twins was recruited through linkage between the Danish national registries (N=204). Participants were grouped as: affected (remitted BD/UD; n = 115); high-risk (co-twin with history of BD/UD; n = 49), or low-risk (no co-twin history of BD/UD; n = 40). Twins completed mental imagery measures spanning key subjective domains (spontaneous imagery use and emotional imagery) and cognitive domains (imagery inspection and imagery manipulation).Results: Affected twins in remission reported enhanced emotional mental imagery compared to both low- and high-risk twins. This was characterized by greater impact of i) intrusive prospective imagery (Impact of Future Events Scale) and ii) deliberately-generated prospective imagery of negative scenarios (Prospective Imagery Task). There were no significant differences in these key measures between affected BD and UD twins in remission. Additionally, low- and high-risk twins did not significantly differ on these emotional imagery measures. There were also no significant differences between the three groups on non-emotional measures including spontaneous imagery use and cognitive stages of imagery.Conclusions: Abnormalities in emotional prospective imagery are present in monozygotic twins with affective disorders in remission—despite preserved cognitive stages of imagery—but absent in unaffected high-risk twins, and thus do not appear to index familial risk (i.e., unlikely to qualify as “endophenotypes”). Elevated emotional prospective imagery represents a promising treatment/prevention target in affective disorders.

Background: Broken Hill is home to Australia's oldest silver–zinc–lead mine. However, the precise source of childhood blood lead (PbB) exposures has been subject to considerable debate. Lead sources include natural soil Pb enrichment, legacy deposition, contemporary mining emissions, and Pb-based paint. Objective: To test whether contemporary mining emissions independently affect childhood PbB in Broken Hill. Methods: Children's (

Multiple studies in India have found elevated blood lead levels (BLLs) in target populations. However the data have not yet been evaluated to understand population-wide exposure levels. We used arithmetic mean blood lead data published from 2010 to 2018 on Indian populations to calculate the average BLLs for multiple subgroups. We then calculated the attributable disease burden in IQ decrement and Disability Adjusted Life Years (DALYs). Our Pubmed search yielded 1066 articles. Of these, 31 studies representing the BLLs of 5472 people in 9 states met our study criteria. Evaluating these, we found a mean BLL of 6.86 μg/dL (95% CI: 4.38–9.35) in children and 7.52 μg/dL (95% CI: 5.28–9.76) in non-occupationally exposed adults. We calculated that these exposures resulted in 4.9 million DALYs (95% CI: 3.9–5.6) in the states we evaluated. Population-wide BLLs in India remain elevated despite regulatory action to eliminate leaded petrol, the most significant historical source. The estimated attributable disease burden is larger than previously calculated, particularly with regard to associated intellectual disability outcomes in children. Larger population-wide BLL studies are required to inform future calculations. Policy responses need to be developed to mitigate the worst exposures. Keywords: Blood, Lead, India, Meta-analysis, DALYs, Contamination

This study examines residential indoor dust from 224 homes in Sydney, Australia for trace element concentrations measured using portable X-ray Fluorescence (pXRF) and their potential risk of harm. Samples were collected as part of a citizen science program involving public participation via collection and submission of vacuum dust samples for analysis of their As, Cr, Cu, Mn, Ni, Pb and Zn concentrations. The upper 95% confidence level of the mean values for 224 samples (sieved to 1 suggests potential non-carcinogenic health effects. Carcinogenic risks were estimated for As, Cr and Pb whose carcinogenic slope factors (CSF) were available. Only the risk factor for Cr exceeded the US EPA's carcinogenic threshold (1 × 10−4) for children. Children aged 1–2 years had the highest predicted mean child blood lead (PbB) of 4.6 μg/dL, with 19.2% potentially having PbB exceeding 5 μg/dL and 5.80% exceeding 10 μg/dL. The Cr and Pb levels measured in indoor dust therefore pose potentially significant adverse health risks to children. Keywords: Household dust, Trace metals, Human exposure assessment, Public health, Interventions

Abstract Environmental remediation efforts in low‐ and middle‐income countries have yet to be evaluated for their cost effectiveness. To address this gap we calculate a cost per Disability Adjusted Life Year (DALY) averted following the environmental remediation of the former lead smelter and adjoining residential areas in Paraiso de Dios, Haina, the Dominican Republic, executed from 2009 to 2010. The remediation had the effect of lowering surface soil lead concentrations to below 100 mg/kg and measured geometric mean blood lead levels (BLLs) from 20.6 μg/dL to 5.34 ug/dL. Because BLLs for the entire impacted population were not available, we use environmental data to calculate the resulting disease burden. We find that before the intervention 176 people were exposed to elevated environmental lead levels at Paraiso de Dios resulting in mean BLLs of 24.97 (95% CI: 24.45–25.5) in children (0–7 years old) and 13.98 μg/dL (95% CI: 13.03–15) in adults. We calculate that without the intervention these exposures would have resulted in 133 to 1,096 DALYs and that all of these were averted at a cost of USD 392 to 3,238, depending on assumptions made. We use a societal perspective, meaning that we include all costs regardless of by whom they were incurred and estimate costs in 2009 USD. Lead remediation in low‐ and middle‐income countries is cost effective according to World Health Organization thresholds. Further research is required to compare the approach detailed here with other public health interventions.

The standard model of early vision claims that orientation and spatial frequency are encoded with multiple, fixed-bandwidth, and approximately independent channels. The standard model was developed from observer data that used deterministic patterns such as Gabor patches and gratings used as stimuli, but detection data using noise as a stimulus suggests that the visual system may use adjustable, rather than fixed-bandwidth channels. In our previous work, we used classification images as a key piece of evidence against the adjustable channels hypothesis for spatial frequency. Here we tested the adjustable channels hypothesis for orientation with two-dimensional filtered noise that varied in orientation bandwidth presented in white noise. Unlike spatial frequency, our data were consistent with the predictions of an adjustable channel model; we found quarter-root law thresholds consistent with optimal summation, relatively high and constant absolute efficiency, and classification images that show an adjustment in channel bandwidth. Thus, for orientation summation, both detection thresholds and classification image results support the adjustable channels hypothesis. Classification images also reveal hallmarks of inhibition or suppression from uninformative spatial frequencies and/or orientations. This work highlights the limitations of the standard model of summation for orientation. The standard model of orientation summation and tuning was chiefly developed with narrow-band stimuli that were not presented in noise, stimuli that are arguably less naturalistic than than the variable bandwidth stimuli presented in noise used in our experiments. Finally, the disagreement between the results from our experiments on spatial frequency summation with the data presented in this paper suggests that orientation may be encoded differently, particularly with mechanisms with greater flexibility than spatial frequency channels.

Moral bioenhancement (MBE) aims to fix our moral agency itself in order to prevent us from engaging in negligent or harmful behavior. Although such (self)‐paternalistic practice might very well produce good outcomes, it can be argued – inspired by Kant – that it is intrinsically disrespectful towards our future agency. Hence, we are faced with the following ethical dilemma: the failure to engage in MBE seems reckless and negligent, which can be considered a serious moral wrong; but engaging in MBE presupposes that we treat our faculties (our future agency) in a disrespectful self‐paternalistic manner. In this article, we want to resolve the described dilemma by suggesting a novel way of understanding Kantian objections to MBE. We argue that a careful engagement with Kantian moral psychology does provide a space for MBE but that it also describes a potential danger of MBE that has, at best, been only superficially described. That is, we offer a different Kantian understanding of MBE as a means to bring our empirical and noumenal selves together as a coherent whole to achieve what Kant describes as 'genuine accountability to others'. [ABSTRACT FROM AUTHOR]

Cosmopolitans have argued that coercive statism – the view that egalitarian distributive obligations only exist between co-citizens – is under-motivated. Conversely, republican theorists have argued that the state should remain a primary focus of global justice, relying only upon contingent features of states and the global order. This paper argues for an understanding of freedom as non-domination that grounds both coercive statism and the republican primacy of sovereign states in accounts of global justice. It argues that distributive equality – both political and economic – are uniquely triggered by membership in a state-like polity due to the necessarily unmediated and direct nature of sovereign political authority. Distributive equality is, according to this account, constitutive of freedom in the face of a particular kind of coercive political power. This offers a response to cosmopolitans by showing that distributive equality is a necessary feature of justified state power and undergirds the republican position by showing that the global order is a secondary site of distributive justice. That is, the global order ought to maintain interstate non-domination and help states with domestic equality but need not aim at global political and economic equality. [ABSTRACT FROM AUTHOR]

This paper develops a novel, neo-republican account of just state surveillance in the information age. The goal of state surveillance should be to avoid and prevent domination, both public and private. In light of that conception of justice, the paper makes three substantive points. First, it argues that modern state surveillance based upon information technology and predicated upon a close partnership with the tech sector gives the state significant power and represents a serious potential source of domination. Second, it argues that, nonetheless, state surveillance can serve legitimate republican ends and so unilateral and private technological attempts to block it may be wrongful. Third, it argues that, despite the serious normative failings of current institutions, state surveillance can be justly regulated and made accountable through a legal liability regime that incentivizes tech company intermediaries to ally with civil society groups in order to safeguard the privacy rights of potential subjects of state surveillance. [ABSTRACT FROM AUTHOR]

This paper argues that it is permissible for computer scientists and engineers—working with advanced militaries that are making good faith efforts to follow the laws of war—to engage in the research and development of lethal autonomous weapons systems (LAWS). Research and development into a new weapons system is permissible if and only if the new weapons system can plausibly generate a superior risk profile for all morally relevant classes and it is not intrinsically wrong. The paper then suggests that these conditions are satisfied by at least some potential LAWS development programs. More specifically, since LAWS will lead to greater force protection, warfighters are free to become more risk-acceptant in protecting civilian lives and property. Further, various malicious motivations that lead to war crimes will not apply to LAWS or will apply to no greater extent than with human warfighters. Finally, intrinsic objections—such as the claims that LAWS violate human dignity or that it creates 'responsibility gaps'—are rejected on the basis that they rely upon implausibly idealized and atomized understandings of human decision-making in combat. [ABSTRACT FROM AUTHOR]

This paper argues that discussions of transnational authority are hampered by an equivocation between two radically different kinds of authority, each possessing different normative logics. Instrumental authority, which treats political institutions as tools, is amenable to the disunited, pluralistic and highly contextualised nature of transnational governance. Furthermore, instrumental-transnational authority is compatible with the authority and sovereignty of states. Yet, instrumental authority is comparatively weak in terms of the political interventions it can justify. Constitutive authority, on the other hand, can justify much more intrusive and coercive political actions. Yet, I shall argue that only sovereign agents with unified legislative, judicial and executive powers can possess constitutive authority. I investigate different ways in which transnational institutions can be structured--from Slaughter's horizontal networks to Ruggie's substantive multilateralism--in order to illustrate a dilemma: transnational and global institutions can indeed possess authority, but it is of a kind that justifies a relatively narrow and weak set of political interventions. [ABSTRACT FROM AUTHOR]

Abstract Iron ores are principal input materials for iron and steel-making industries. Quality of iron ores is one of the critical parameters for formation of environmental pollutants related to the steel-making process. Dioxins are identified as one of the most toxic pollutants emitted during ironmaking, specifically during the sintering process. This study applied four types of iron ores and analyzed their moisture, density, particle size distribution and element concentrations to investigate their effect on the dioxin formation during sintering. Each type of iron ore was processed in a sinter pot grate. During each processing route, exhausted dust and generated sinter products were collected and subjected to PCDD/F and PCB analysis. Statistical analysis was applied to assess correlations between properties of iron ores and exhausted dioxin emissions, identifying key contributors to dioxin formation during sintering process. Results showed that Fe in iron ores was positively and significantly related to PCB 114 formation in dust and confirmed its co-catalytic effect on dioxin formation. Concentrations of Al, Ti and Cl in iron ores greatly increased PCDD/F and PCB emissions in the sintered products compared to dioxins in dust samples. The S levels and density of iron ores were highly related to the increasing PCDD/F and PCB emissions in both sinter and dust samples. By contrast, concentrations of Si in iron ores played a significant role in decreasing PCDD/F and PCB emissions in both sinter and dust samples. This study also confirmed the optimum size (

We launched the VegeSafe program in 2013 to assist Australians concerned about exposure to contaminants in their soils and gardens. VegeSafe analyses garden soils provided by citizens for trace metals at our laboratory at little to no cost, with easy-to-follow guidance on any intervention required. The response was overwhelming—Australians submitted 17,256 soils from 3,609 homes, and in turn VegeSafe researchers now have unparalleled household-scale data, providing new insights into urban trace metal contamination. The results are sobering, with 35% of homes, particularly those that are older, painted and located in inner cities having soils above the Australian residential guideline (300 mg/kg) for the neurotoxic trace metal lead (Pb). Exposure pathway, blood Pb concentration and vegetable uptake modelling showed the communities in these locations were most at risk. VegeSafe is transformative: 94% of participants better understood contaminants, 83% felt safer in their home environment and 40% undertook remedial action based on their results. The two-way nature of this program enables education of citizens about environmental contaminants, advances public health, and delivers impactful science.

Here we detail the soil to vegetable transfer factor (uptake) data and calculation procedures for vegetable trace metal uptake estimation that are presented in Taylor et al. (2021).Firstly, we present the literature review of trace metal uptake data, describing uptake from soil to vegetable produce determined in global experimental studies. After selecting the uptake factors most applicable to the VegeSafe dataset, using similar soil trace metal concentrations and studies that consider only the edible parts of plants, we applied these uptake factors to VegeSafe soils. Using this approach, we were able to estimate trace metal concentrations in home grown produce across the 3,609 homes included in our VegeSafe study.Using Australian and global food standards, we calculated the soil trace metal concentrations that would potentially result in exceedance of Australian and global food safety criteria. Our process followed the method detailed in the Australian soil guidelines (NEPM, 2013). Also presented are the numbers of individual samples and vegetable gardens that are likely to exceed food safety criteria in the three largest cities of Australia: Sydney, Melbourne and Brisbane. Individual household vegetable garden trace metal uptake data were aggregated across standarised geographic areas (Statistical Area Level 3) as established by the Australian Bureau of Statistics to visualise the geospatial distribution of potential trace metal risk from home produce.These modelled data provide the basis for prioritising locations, trace metals and soils for future empirically-based studies of trace metal contamination in home-grown produce.

Background: The city of Port Pirie in South Australia has been a world leading centre for lead and zinc smelting and processing since 1889 that continues to cause contamination of its environment and resident population. This study quantifies the effect of lead and SO2 emissions from Nyrstar Port Pirie Pty Ltd's smelter on blood lead and respiratory health outcomes, respectively, and establishes what air quality values are required to better protect human health. Method: Blood lead and emergency department presentation data collected by South Australia Health (SA Health) and lead in air and SO2 data collected by the South Australian Environment Protection Authority (SAEPA) were obtained and analysed to quantify health outcomes due to smelter emissions in Port Pirie. Regression analysis was used to assess the relationship between the concentration of lead in air and children's blood lead levels between the years of available data: 2003 to 2017. Ambient SO2 concentrations (SAEPA) measured continuously between 2008 and 2018 were 24-hour averaged and compared to daily local emergency department respiratory presentation rates (available from July 2012 to October 2018). Rates of emergency department respiratory presentations at Port Pirie and regional comparators were calculated as age-standardised rates. Results: The data show that increases in ambient SO2 concentrations are associated with increased rates of emergency department respiratory presentations of Port Pirie residents, in which children are over-represented. The 30-day rolling average of respiratory presentations was significantly associated (p

Background. The informal settlement of Owino Uhuru near an abandoned lead smelter attracted international attention due to an apparent lead poisoning event. Despite this attention, the environmental data collected to date do not indicate high levels of residual contamination. Objectives. To further confirm previous findings and determine any necessary risk mitigation measures, an assessment of surface soil lead concentrations was conducted in the community. Methods. Investigators carried out an assessment of the soil in a ~12,000 m2 section of the Owino Uhuru neighborhood over the course of a single day in June 2017 with the assistance of community leaders. Fifty-nine in situ soil measurements were taken using an Innov-X tube-based (40 kV) alpha X-ray fluorescence instrument (pXRF). Results. The assessment found that mean surface soil lead concentrations in areas conducive to exposure were 110 mg/kg (95% CI: 54–168); below United States Environmental Protection Agency and the Environment Canada screening levels of 400 mg/kg and 140 mg/kg, respectively. Conclusions. There is likely no current need for risk mitigation activities in the community. These results could inform discussions on the allocation of public health spending. Competing Interests. The authors declare no competing financial interests. BE, VOO, CN and JSF are employees of Pure Earth. MPT sits on the Editorial Board of the Journal of Health and Pollution.

BackgroundPrior calculations of the burden of disease from environmental lead exposure in low- and middle-income countries (LMICs) have not included estimates of the burden from lead-contaminated sites because of a lack of exposure data, resulting in an underestimation of a serious public health problem.ObjectiveWe used publicly available statistics and detailed site assessment data to model the number of informal used lead-acid battery (ULAB) recyclers and the resulting exposures in 90 LMICs. We estimated blood lead levels (BLLs) using the US Environment Protection Agency’s Integrated Exposure Uptake Biokinetic Model for Lead in Children and Adult Lead Model. Finally, we used data and algorithms generated by the World Health Organization to calculate the number of attributable disability adjusted life years (DALYs).ResultsWe estimated that there are 10,599 to 29,241 informal ULAB processing sites where human health is at risk in the 90 countries we reviewed. We further estimated that 6 to 16.8 million people are exposed at these sites and calculate a geometric mean BLL for exposed children (0-4 years of age) of 31.15 μg/dL and a geometric mean BLL for adults of 21.2 μg/dL. We calculated that these exposures resulted in 127,248 to 1,612,476 DALYs in 2013.ConclusionsInformal ULAB processing is currently causing widespread lead poisoning in LMICs. There is an urgent need to identify and mitigate exposures at existing sites and to develop appropriate policy responses to minimize the creation of new sites.

This study details the first comprehensive evaluation of the efficacy of a soil lead mitigation project in Dong Mai village, Vietnam. The village's population had been subject to severe lead poisoning for at least a decade as a result of informal Used Lead Acid Battery (ULAB) recycling. Between July 2013 to February 2015, Pure Earth and the Centre for Environment and Community Development (Hanoi, Vietnam) implemented a multi-faceted environmental and human health intervention. The intervention consisted of a series of institutional and low-cost engineering controls including the capping of lead contaminated surface soils, cleaning of home interiors, an education campaign and the construction of a work-clothes changing and bathing facility. The mitigation project resulted in substantial declines in human and environmental lead levels. Remediated home yard and garden areas decreased from an average surface soil concentration of 3940 mg/kg to <100 mg/kg. One year after the intervention, blood lead levels in children (<6 years old) were reduced by an average of 67%—from a median of 40.4 μg/dL to 13.3 μg/dL. The Dong Mai project resulted in significantly decreased environmental and biological lead levels demonstrating that low-cost, rapid and well-coordinated interventions could be readily applied elsewhere to significantly reduce preventable human health harm. [ABSTRACT FROM AUTHOR]

The efficient harnessing of solar power for water treatment via photocatalytic processes has long been constrained by the challenge of understanding and optimizing the interactions at the photocatalyst surface, particularly in the presence of nontarget cosolutes. The adsorption of these cosolutes, such as natural organic matter, onto photocatalysts can inhibit the degradation of pollutants, drastically decreasing the photocatalytic efficiency. In the present work, computational methods are employed to predict the inhibitory action of a suite of small organic molecules during TiO 2 photocatalytic degradation of para -chlorobenzoic acid ( p CBA). Specifically, tryptophan, coniferyl alcohol, succinic acid, gallic acid, and trimesic acid were selected as interfering agents against p CBA to observe the resulting competitive reaction kinetics via bulk and surface phase reactions according to Langmuir-Hinshelwood adsorption dynamics. Experiments revealed that trimesic and gallic acids were most competitive with p CBA, followed by succinic acid. Density functional theory (DFT) and machine learning interatomic potentials (MLIPs) were used to investigate the molecular basis of these interactions. The computational findings showed that while the type of functional group did not directly predict adsorption affinity, the spatial arrangement and electronic interactions of these groups significantly influenced adsorption dynamics and corresponding inhibitory behavior. Notably, MLIPs, derived by fine-tuning models pretrained on a vastly larger dataset, enabled the exploration of adsorption behaviors over substantially longer periods than typically possible with conventional ab initio molecular dynamics, enhancing the depth of understanding of the dynamic interaction processes. Our study thus provides a pivotal foundation for advancing photocatalytic technology in environmental applications by demonstrating the critical role of molecular-level interactions in shaping photocatalytic outcomes.

Introduction: According to the Federal Highway Administration, a quarter of fatal collisions has occurred at horizontal curves. The average collision rate at horizontal curves was found to be three times higher than other types of highway segments. The lack of compliance with the speed limit and driver-related factors are among the main contributing factors to those collisions. Vehicle to Infrastructure (V2I) communications can address these limitations by providing drivers with valuable in-vehicle warning messages based on operational and safety data. There is limited effort investigating the impact of different types of V2I warning messages at horizontal curves and among different profiles of drivers. This study aims to thoroughly examine drivers' behavior and compliance with different V2I warning messages when approaching horizontal curves., Methods: A driving simulator experiment and self-reported survey were conducted. Three main hypotheses were analyzed in this study. First, whether supplying drivers with in-vehicle V2I warning messages will positively affect drivers' behavior at horizontal curves compared to the standard road signs. Second, whether there will be a significant difference in drivers' behavior when receiving text and audio V2I warning messages. Third, whether seniors and female drivers will comply more with speed limit advisory provided through V2I message than younger and male drivers., Results: The Analysis of Covariance confirmed the first two hypotheses. Two main measures of drivers' behavior found to be lower in the V2I communication scenarios compared to the base one. The audio warning message was found to be more promising in increasing drivers' compliance with speed limit advisory when approaching the curves. Analyzing the third hypothesis revealed that younger and male drivers had higher curve initiation speed compared to females and seniors., Practical Applications: The findings of this study can be used by transportation researchers, authorities, and car manufacturers to improve the effectiveness of in-vehicle V2I warning messages among different profiles of drivers., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

Recent research revealed that COVID-19 pandemic was associated with noticeable changes in travel demand, traffic volumes, and traffic safety measures. Despite the reduction of traffic volumes across the US, several recent studies indicated that crash rates increased across different states during COVID-19 pandemic. Although some recent studies have focused on examining the changes in traffic conditions and crash rates before and during the pandemic, not enough research has been conducted to identify risk factors to crash severity. Even the limited research addressing the contributing factors to crash severity were focused on the pool category of drivers and no insight is available regarding older drivers, one of the most vulnerable groups to traffic collision and coronavirus. Moreover, these studies investigated the early impact of the COVID-19 pandemic mostly using up to three months of data. However, near-term and long-term effects of the COVID-19 pandemic are still unknown on traffic collisions. Therefore, this study aims to contribute to the literature by studying the near-term impact of the COVID-19 pandemic on crash size and severity among older drivers. To this end, a relatively large sample of crash data with senior drivers at fault was obtained and analyzed. To identify the main contributing factors affecting crash outcomes, Exploratory Factor Analysis was conducted on a high-dimension data set to identify potential latent factors which were validated through Confirmatory Factor Analysis. After that, Structural Equation Modeling technique was performed to examine the associations among the identified independent latent factors and the dependent variable. Additionally, SEM model identified the impact of the COVID-19 pandemic on seniors' crash severity. The findings reveal that several latent variables were the significant predictors of crash severity of older drivers including "Driving maneuver & crash location", "Road features and traffic control devices", "Driver condition & behavior", "Road geometric characteristics", "Crash time and lighting", and "Road class" latent factors. The binary variable of "Pandemic" was found to be as highly significant as the last four latent factors mentioned above. This means not only were older drivers more likely to be involved in higher crash size with higher severity level during the pandemic period, but also "Pandemic" was a risk factor to seniors as much as "Driver condition & behavior", "Road geometric characteristics", "Crash time & lighting", and "Road class" factors. The results of this study provide useful insights that may improve road safety among senior drivers during pandemic periods like COVID-19., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

In the face of significant challenges to practical applications of photocatalysis for water treatment, recent reports revealed a potential route to overcome a problem posed by dissolved organic matter (DOM). These studies showed that inhibition of photocatalytic processes by DOM is driven largely by competition for active surface sites on TiO 2 or other catalysts, and controlling the type of DOM present in solution could significantly mitigate DOM fouling. Whether or not control of solution parameters could achieve the same preventative action is not known. Here, a series of DOM isolates, including humic acid (HA) and transphilic (TPI), hydrophobic (HPO), or colloidal fractions of organic matter from a membrane bioreactor mixed liquor supernatant, were tested for inhibitory activity under a range of pH values (3, 5, 7, and 9) and ionic compositions (NaCl, CaCl 2 , and Al 2 (SO 4 ) 3 with ionic strengths (IS) ranging from 0 to 3 M). The resulting TiO 2 -DOM agglomerates were monitored for size and ζ-potential. Inhibitory profiles were generated using para -chlorobenzoic acid ( p CBA) as probe with varying concentrations of inhibitory DOM for each solution condition to discern the extent of surface-phase quenching of radicals. Manipulation of pH clearly impacted inhibition, and the effect varied by DOM type; for example, interference occurred at all pHs for HA, at neutral or basic pHs for TPI, and only at pH 7 for HPO. Particle sizes did not correlate with inhibitory action of DOM. Increases in ionic strength induced growth of TiO 2 and TiO 2 -DOM agglomerates, but again, particle sizes did not correlate to inhibition by DOM. The changes to IS, regardless of ion type, were not affected by the presence of TPI or HPO. Since particle stability did not correlate directly with photocatalytic activity, we suggest that surface-based quenching reactions arise from site-specific adsorption rather than generalized particle destabilization and aggregation.

Introduction: Autonomous vehicles (AVs) are considered a promising solution to improve seniors' safety and mobility. However, to transition to fully automated transportation, especially among seniors, it is vital to assess their perception and attitude toward AVs. This paper investigates seniors' perceptions and attitudes to a wide range of AV options from the perspective of pedestrians and users in general, as well as during and after the COVID-19 pandemic. Underlying this objective is to examine older pedestrians' safety perceptions and behaviors at crosswalks in the presence of AVs., Method: A national survey collected data from a sample of 1,000 senior Americans. Using Principal Component Analysis (PCA) and Cluster Analysis, three clusters of seniors were identified with different demographic characteristics, perceptions, and attitudes toward AVs., Results: PCA findings revealed that "risky pedestrian crossing behavior," "cautious pedestrian crossing behavior in the presence of AVs," "positive perception and attitude toward shared AVs," and "demographic characteristics" were the main components explaining most of the variation within the data, respectively. The PCA factor scores were used in the cluster analysis, which resulted in the identification of three distinctive groups of seniors. Cluster one included individuals with lower demographic scores and a negative perception and attitude toward AVs from the perspective of users and pedestrians. Clusters two and three included individuals with higher demographic scores. Cluster two included individuals with a positive perception toward shared AVs from the user perspective, but a negative attitude toward pedestrian-AV interaction. Cluster three included those with a negative perception toward shared AVs but a somewhat positive attitude toward pedestrian-AV interaction. The findings of this study provide valuable insights to transportation authorities, AV manufacturers, and researchers regarding older American's perception and attitude toward AVs as well as their willingness to pay and use Advanced Vehicle Technologies., Competing Interests: Conflict of Interest None., (Published by Elsevier Ltd.)

This paper offers a novel understanding of collective responsibility for AI outcomes that can help resolve the "problem of many hands" and "responsibility gaps" when it comes to AI failure, especially in the context of lethal autonomous weapon systems., Competing Interests: The author declares that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2022 Smith.)

Fullerene's low water solubility was a serious challenge to researchers aiming to harness their excellent photochemical properties for aqueous applications. Cationic functionalization of the fullerene cage provided the most effective approach to increase water solubility, but common synthesis practices inadvertently complicated the photochemistry of these systems by introducing iodide as a counterion. This problem was overlooked until recent work noted a potentiation effect which occurred when photosensitizers were used to inactivate microorganisms with added potassium iodide. In this work, several photochemical pathways were explored to determine the extent and underlying mechanisms of iodide's interference in the photosensitization of singlet oxygen by cationic fulleropyrrolidinium ions and rose bengal. Triplet excited state sensitizer lifetimes were measured via laser flash photolysis to probe the role of I - in triplet sensitizer quenching. Singlet oxygen production rates were compared across sensitizers in the presence or absence of I - , SO 4 2- , and other anions. 3,5-Dimethyl-1 H -pyrazole was employed as a chemical probe for iodine radical species, such as I·, but none were observed in the photochemical systems. Molecular iodine and triiodide, however, were found in significant quantities when photosensitizers were irradiated in the presence of I - and O 2 . The formation of I 2 in these photochemical systems calls into question the interpretations of prior studies that used I - as a counterion for photosensitizer materials. As an example, MS2 bacteriophages were inactivated here by cationic fullerenes with and without I - present, showing that I - moderately accelerated the MS2 deactivation, likely by producing I 2 . Production of I 2 did not appear to be directly correlated with estimates of 1 O 2 concentration, suggesting that the relevant photochemical pathways are more complex than direct reactions between 1 O 2 and I - in the bulk solution. On the basis of the results here, iodine photochemistry may be underappreciated and misunderstood in other environmental systems.

An extensive survey of open literature reveals the need for a unifying approach for characterizing the degradation of tribo-pairs. This paper focuses on recent efforts made towards developing unified relationships for adhesive-type wear under unlubricated conditions through a thermodynamic framework. It is shown that this framework can properly characterize many complex scenarios, such as degradation problems involving unidirectional, bidirectional (oscillatory and reciprocating motions), transient operating conditions (e.g., during the running-in period), and variable loading/speed sequencing.

Older pedestrians (65 years and above) are among the most vulnerable road users. As the number and proportion of older adults grows in many countries, and awareness of the benefits of active travel becomes increasingly evident, it behooves researchers to further investigate the safety of older pedestrians. This study contributes to the literature by examining the factors that influence older adults' susceptibility to pedestrian incidents (falls incidents and pedestrian-vehicle collisions). To this end, a sample of older adults living in the Greater Golden Horseshoe, South Ontario, Canada was surveyed. The data were analyzed using descriptive statistics, Confirmatory Factor Analysis (CFA) and Structural Equation Modeling (SEM), to identify several latent factors that are significantly associated with older adults' involvement in pedestrian incidents. The results revealed that the factors that affect older adults' susceptibility to pedestrian incidents are level of difficulty while walking, fear of falling, and crossing evaluation capability. In contrast, level of pedestrian confidence and level of risk-taking crossing behavior are not among the significant factors. It was also found that older pedestrians aged 65-75 years, males, and those who are still working had a greater probability to be involved in pedestrian incidents. These findings shed light on some key constraints of older pedestrians, and the extent to which each factor could improve their safety. This information, in turn, can be used by transportation authorities in prioritizing their plans, policies, and programs towards improving the safety and mobility of older pedestrians., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

Highway work zones are most vulnerable roadway segments for congestion and traffic collisions. Hence, providing accurate and timely prediction of the severity of traffic collisions at work zones is vital to reduce the response time for emergency units (e.g., medical aid), accordingly improve traffic safety and reduce congestion. In predicting the severity of traffic collisions, previous studies used different statistical and machine learning models with accuracy as the main evaluating factor. However, the performance of these models was generally not good, especially on fatal and injury crashes. Also, looking into the prediction accuracy only is misleading. This paper aims to propose a novel deep learning-based approach with a customized f1-loss function to predict the severity of traffic crashes. Underlying this objective is to compare the results of deep learning models with machine learning model considering two performance indicators, namely precision, and recall. The data used in the analysis include a sample of traffic crashes that occurred at work zones in Louisiana from 2014 to 2018. This dataset includes valuable information (features) related to road, vehicle, and human factors affecting the occurrence and severity of those crashes. The proposed methodology is based on transforming these features/variables into images. Image transformation is conducted using a nonlinear dimensionality reduction technique t-SNE and convex hull algorithm. A CNN based deep learning algorithm with a customized loss function was used to directly optimize the model for precision and recall. The results showed improved performance in predicting the crash severity of fatal and injury crashes using the deep learning approach, which can help to improve traffic safety as well as traffic congestion at work zones and possibly other roadways segments., (Copyright © 2021 Elsevier Ltd. All rights reserved.)