Visual Style Elements in Human-System Interface Design for Nuclear Power Operations: Does Style Affect Performance and Preference?

OBJECTIVE: As the world increasingly adopts renewable and sustainable energy systems, transitionary solutions include nuclear power, which currently provides 20% of the United States' electricity and is the largest single source of carbon-free electricity generation. Advanced reactors are a critical component of a carbon-free mixed energy portfolio that require careful design of first-of-a-kind control rooms. BACKGROUND: The application of Human Factors Engineering (HFE) is essential for scientific and iterative testing of novel human-system interface (HSI) concepts to ensure effective, efficient, and safe plant operations. Microworlds are simulators that use simplified physics models and control systems to distill nuclear power operations into essential functions. METHOD: HFE scientists used the Rancor Microworld Simulator to obtain preference and performance metrics for novel and traditional static HSI design styles. Participants comprised advanced reactor company employees and nuclear industry consultants. A mixture of quantitative and qualitative data was captured. RESULTS: There was a preference for the basic graphical style that included high contrast and traditional color scheme elements. No single HSI design outperformed the others, and the participants did not perform better using their preferred HSI style. CONCLUSION: This experiment is the first in a series of HFE testing for HSIs in advanced reactor control room development. Clear user preferences emerged for elements within static displays. The cutting-edge neumorphic style was the least preferred. Future directions include tests of dynamic displays. APPLICATION: HFE is used in evaluating and designing HSI devices that will improve the efficiency and safety of advanced nuclear power operations.

WEPPcloud hydrologic and erosion simulation datasets from 28 watersheds in US Pacific Northwest and calibrating model parameters for undisturbed and disturbed forest management conditions.

The WEPPcloud interface is a new online decision-support tool for the Water Erosion Prediction Project (WEPP) model that facilitates data preparation and model runs, and summarizes model outputs into tables and maps that are easily interpretable by users. The interface can be used by land and water managers in United States, Europe, and Australia interested in simulating streamflow, sediment and pollutant loads from both undisturbed and disturbed (e.g. post-wildfire or post-treatment such as thinning or prescribed fires) forested watersheds. This article contains full hydrologic model runs for 28 forested watersheds in the U.S. Pacific Northwest with the WEPPcloud online interface. It also includes links to repositories with the individual model runs, a table containing default model parameters for disturbed conditions, and figures with model outputs as compared to observed data. The data in the repositories include all the raw data input and output from the model as well as the processed data, which can be accessed through tables and shapefiles to provide additional insights into the model outputs. Lastly, the article describes how the data are organized and the content of each folder containing the data. These model runs are useful for anyone interested in modeling forested watersheds with the WEPPcloud interface.

Designing tools to predict and mitigate impacts on water quality following the Australian 2019/2020 wildfires: Insights from Sydney's largest water supply catchment.

The 2019/2020 Australian bushfires (or wildfires) burned the largest forested area in Australia's recorded history, with major socio-economic and environmental consequences. Among the largest fires was the 280 000 ha Green Wattle Creek Fire, which burned large forested areas of the Warragamba catchment. This protected catchment provides critical ecosystem services for Lake Burragorang, one of Australia's largest urban supply reservoirs delivering ~85% of the water used in Greater Sydney. Water New South Wales (WaterNSW) is the utility responsible for managing water quality in Lake Burragorang. Its postfire risk assessment, done in collaboration with researchers in Australia, the UK, and United States, involved (i) identifying pyrogenic contaminants in ash and soil; (ii) quantifying ash loads and contaminant concentrations across the burned area; and (iii) estimating the probability and quantity of soil, ash, and associated contaminant entrainment for different rainfall scenarios. The work included refining the capabilities of the new WEPPcloud-WATAR-AU model (Water Erosion Prediction Project cloud-Wildfire Ash Transport And Risk-Australia) for predicting sediment, ash, and contaminant transport, aided by outcomes from previous collaborative postfire research in the catchment. Approximately two weeks after the Green Wattle Creek Fire was contained, an extreme rainfall event (~276 mm in 72 h) caused extensive ash and sediment delivery into the reservoir. The risk assessment informed on-ground monitoring and operational mitigation measures (deployment of debris-catching booms and adjustment of the water supply system configuration), ensuring the continuity of safe water supply to Sydney. WEPPcloud-WATAR-AU outputs can prioritize recovery interventions for managing water quality risks by quantifying contaminants on the hillslopes, anticipating water contamination risk, and identifying areas with high susceptibility to ash and sediment transport. This collaborative interaction among scientists and water managers, aimed also at refining model capabilities and outputs to meet managers' needs, exemplifies the successful outcomes that can be achieved at the interface of industry and science. Integr Environ Assess Manag 2021;17:1151-1161. © 2021 The Authors. Integrated Environmental Assessment and Management published by Wiley Periodicals LLC on behalf of Society of Environmental Toxicology & Chemistry (SETAC).

Detection and Direction Determination of Approaching Vehicle Noises Among Older Adults.

We examined detection and direction determination of auditory cues from a pedestrian environment among a sample of older and younger adults. Review of relevant research suggests normal aging is associated with declines in physical, cognitive, and perceptual abilities. Relatively, few studies have examined the impact of such developmental changes on pedestrian safety among older adults, and none have examined such factors in relation to use of auditory cues. Thirty-five younger and 35 older adults completed cognitive measures and a pedestrian auditory detection task. Some results by speed were similar to past research that examined younger samples. Interactions were discovered between age and speed conditions within the auditory task. Results are discussed in the context of past research and with regard to informing future injury prevention efforts.

The phenotype of a phospholipase C (plc-1) mutant in a filamentous fungus, Neurospora crassa.

In the filamentous fungus Neurospora crassa, phospholipase C may play a role in hyphal extension at the growing tips as part of a growth-sensing mechanism that activates calcium release from internal stores to mediate continued expansion of the hyphal tip. One candidate for a tip-localized phospholipase C is PLC-1. We characterized morphology and growth characteristics of a knockout mutant (KO plc-1) and a RIP mutated strain (RIP plc-1) (missense mutations and a nonsense mutation render the gene product non-functional). Growth and hyphal cytology of wildtype and KO plc-1 were similar, but the RIP plc-1 mutant grew slower and exhibited abnormal membrane structures at the hyphal tip, imaged using the fluorescence dye FM4-64. To test for causes of the slower growth of the RIP plc-1 mutant, we examined its physiological poise compared to wildtype and the KO plc-1 mutant. The electrical properties of all three strains and the electrogenic contribution of the plasma membrane H(+)-ATPase (identified by cyanide inhibition) were the same. Responses to high osmolarity were also similar. However, the RIP plc-1 mutant had a significantly lower turgor, a possible cause of its slower growth. While growth of all three strains was inhibited by the phospholipase C inhibitor 3-nitrocoumarin, the RIP plc-1 mutant did not exhibit hyphal bursting after addition of the inhibitor, observed in both wildtype and the KO plc-1 mutant. Although the plc-1 gene is not obligatory for tip growth, the phenotype of the RIP plc-1 mutant - abnormal tip cytology, lower turgor and resistance to inhibitor-induced hyphal bursting - suggest it does play a role in tip growth. The expression of a dysfunctional plc-1 gene may cause a shift to alternative mechanism(s) of growth sensing in hyphal extension.

Mass flow and velocity profiles in Neurospora hyphae: partial plug flow dominates intra-hyphal transport.

Movement of nuclei, mitochondria and vacuoles through hyphal trunks of Neurospora crassa were vector-mapped using fluorescent markers and green fluorescent protein tags. The vectorial movements of all three were strongly correlated, indicating the central role of mass (bulk) flow in cytoplasm movements in N. crassa. Profiles of velocity versus distance from the hyphal wall did not match the parabolic shape predicted by the ideal Hagen-Poiseuille model of flow at low Reynolds number. Instead, the profiles were flat, consistent with a model of partial plug flow due to the high concentration of organelles in the flowing cytosol. The intra-hyphal pressure gradients were manipulated by localized external osmotic treatments to demonstrate the dependence of velocity (and direction) on pressure gradients within the hyphae. The data support the concept that mass transport, driven by pressure gradients, dominates intra-hyphal transport. The transport occurs by partial plug flow due to the organelles in the cytosol.

Developmental differences in auditory detection and localization of approaching vehicles.

Pedestrian safety is a significant problem in the United States, with thousands being injured each year. Multiple risk factors exist, but one poorly understood factor is pedestrians' ability to attend to vehicles using auditory cues. Auditory information in the pedestrian setting is increasing in importance with the growing number of quieter hybrid and all-electric vehicles on America's roadways that do not emit sound cues pedestrians expect from an approaching vehicle. Our study explored developmental differences in pedestrians' detection and localization of approaching vehicles. Fifty children ages 6-9 years, and 35 adults participated. Participants' performance varied significantly by age, and with increasing speed and direction of the vehicle's approach. Results underscore the importance of understanding children's and adults' use of auditory cues for pedestrian safety and highlight the need for further research.

Auditory detection and localization of approaching vehicles.

Pedestrians must use a variety of cues when making safe decisions, many of which require processing of auditory information. We examined detection and localization of approaching vehicles using auditory cues. 50 adults ages 18-49 were presented with actual sounds of vehicles approaching at 5, 12, 25, and 35 mph. Three indices were of interest: the distance at which vehicles were detected, participants' decision regarding the direction from which vehicles were approaching, and their determination of the vehicles' arrival at their location. Participants more easily detected vehicles moving at higher speeds and vehicles approaching from the right. Determination of the direction of approach reached 90% accuracy or better when vehicles were traveling at, or greater than, 12 mph, and were more approaching from the right. Determination of vehicle arrival deteriorated significantly as speeds increased. Implications of the use of auditory cues in pedestrian settings, and future directions, are discussed.

Electrical phenotypes of calcium transport mutant strains of a filamentous fungus, Neurospora crassa.

We characterized the electrical phenotypes of mutants with mutations in genes encoding calcium transporters-a mechanosensitive channel homolog (MscS), a Ca(2+)/H(+) exchange protein (cax), and Ca(2+)-ATPases (nca-1, nca-2, nca-3)-as well as those of double mutants (the nca-2 cax, nca-2 nca-3, and nca-3 cax mutants). The electrical characterization used dual impalements to obtain cable-corrected current-voltage measurements. Only two types of mutants (the MscS mutant; the nca-2 mutant and nca-2-containing double mutants) exhibited lower resting potentials. For the nca-2 mutant, on the basis of unchanged conductance and cyanide-induced depolarization of the potential, the cause is attenuated H(+)-ATPase activity. The growth of the nca-2 mutant-containing strains was inhibited by elevated extracellular Ca(2+) levels, indicative of lesions in Ca(2+) homeostasis. However, the net Ca(2+) effluxes of the nca-2 mutant, measured noninvasively with a self-referencing Ca(2+)-selective microelectrode, were similar to those of the wild type. All of the mutants exhibited osmosensitivity similar to that of the wild type (the turgor of the nca-2 mutant was also similar to that of the wild type), suggesting that Ca(2+) signaling does not play a role in osmoregulation. The hyphal tip morphology and tip-localized mitochondria of the nca-2 mutant were similar to those of the wild type, even when the external [Ca(2+)] was elevated. Thus, although Ca(2+) homeostasis is perturbed in the nca-2 mutant (B. J. Bowman et al., Eukaryot. Cell 10:654-661, 2011), the phenotype does not extend to tip growth or to osmoregulation but is revealed by lower H(+)-ATPase activity.

How does a hypha grow? The biophysics of pressurized growth in fungi.

The mechanisms underlying the growth of fungal hyphae are rooted in the physical property of cell pressure. Internal hydrostatic pressure (turgor) is one of the major forces driving the localized expansion at the hyphal tip which causes the characteristic filamentous shape of the hypha. Calcium gradients regulate tip growth, and secretory vesicles that contribute to this process are actively transported to the growing tip by molecular motors that move along cytoskeletal structures. Turgor is controlled by an osmotic mitogen-activated protein kinase cascade that causes de novo synthesis of osmolytes and uptake of ions from the external medium. However, as discussed in this Review, turgor and pressure have additional roles in hyphal growth, such as causing the mass flow of cytoplasm from the basal mycelial network towards the expanding hyphal tips at the colony edge.

Architecture and development of the Neurospora crassa hypha -- a model cell for polarized growth.

Neurospora crassa has been at the forefront of biological research from the early days of biochemical genetics to current progress being made in understanding gene and genetic network function. Here, we discuss recent developments in analysis of the fundamental form of fungal growth, development and proliferation -- the hypha. Understanding the establishment and maintenance of polarity, hyphal elongation, septation, branching and differentiation are at the core of current research. The advances in the identification and functional dissection of regulatory as well as structural components of the hypha provide an expanding basis for elucidation of fundamental attributes of the fungal cell. The availability and continuous development of various molecular and microscopic tools, as utilized by an active and co-supportive research community, promises to yield additional important new discoveries on the biology of fungi.

Mid1, a mechanosensitive calcium ion channel, affects growth, development, and ascospore discharge in the filamentous fungus Gibberella zeae.

The role of Mid1, a stretch-activated ion channel capable of being permeated by calcium, in ascospore development and forcible discharge from asci was examined in the pathogenic fungus Gibberella zeae (anamorph Fusarium graminearum). The Δmid1 mutants exhibited a >12-fold reduction in ascospore discharge activity and produced predominately abnormal two-celled ascospores with constricted and fragile septae. The vegetative growth rate of the mutants was ∼50% of the wild-type rate, and production of macroconidia was >10-fold lower than in the wild type. To better understand the role of calcium flux, Δmid1 Δcch1 double mutants were also examined, as Cch1, an L-type calcium ion channel, is associated with Mid1 in Saccharomyces cerevisiae. The phenotype of the Δmid1 Δcch1 double mutants was similar to but more severe than the phenotype of the Δmid1 mutants for all categories. Potential and current-voltage measurements were taken in the vegetative hyphae of the Δmid1 and Δcch1 mutants and the wild type, and the measurements for all three strains were remarkably similar, indicating that neither protein contributes significantly to the overall electrical properties of the plasma membrane. Pathogenicity of the Δmid1 and Δmid1Δcch1 mutants on the host (wheat) was not affected by the mutations. Exogenous calcium supplementation partially restored the ascospore discharge and vegetative growth defects for all mutants, but abnormal ascospores were still produced. These results extend the known roles of Mid1 to ascospore development and forcible discharge. However, Neurospora crassa Δmid1 mutants were also examined and did not exhibit defects in ascospore development or in ascospore discharge. In comparison to ion channels in other ascomycetes, Mid1 shows remarkable adaptability of roles, particularly with regard to niche-specific adaptation.

Ion and oxygen fluxes in the unicellular alga Eremosphaera viridis.

Plasma membrane fluxes of the large unicellular model algal cell Eremosphaera viridis (De Bary) were measured under various light regimes to explore the role of plasma membrane fluxes during photosynthesis and high light-induced chloroplast translocation. Plasma membrane fluxes were measured directly and non-invasively with self-referencing ion-selective (H(+), Ca(2+), K(+) and Cl(-)) potentiometric microelectrodes and oxygen amperometric microelectrodes. At light irradiances high enough to induce chloroplast migration from the cell periphery to its center, oxygen evolution declined to respiratory net O(2) uptake prior to any significant chloroplast translocation, while net K(+) and Cl(-) influx increased during the decline in photosynthetic activity (and the membrane potential depolarized). The results suggest that chloroplast translocation is not the cause of the cessation of O(2) evolution at high irradiance. Rather, the chloroplast translocation may play a protective role: shielding the centrally located nucleus from damaging light intensities. At both high and low light intensities (similar to ambient growth conditions), there was a strong inverse correlation between H(+) net fluxes and respiratory and photosynthetic net O(2) fluxes. A similar inverse relationship was also observed for Ca(2+) net fluxes, but only at higher light intensities. The net H(+) fluxes are small relative to the buffering capacity of the cell, but are clearly related to both photosynthetic and respiratory activity.

Turgor and net ion flux responses to activation of the osmotic MAP kinase cascade by fludioxonil in the filamentous fungus Neurospora crassa.

The internal hydrostatic pressure (turgor) of the filamentous fungus Neurospora crassa is regulated at about 400-500 kiloPascals, primarily by an osmotic MAP kinase cascade which activates ion uptake from the extracellular medium and glycerol synthesis. In the absence of hyperosmotic stress, the phenylpyrrole fungicide fludioxonil activates the osmotic MAP kinase cascade, resulting in cell death. Turgor, the electrical potential and net ion fluxes were measured after treatment with fludioxonil. In wildtype, fludioxonil causes a hyperpolarization of the plasma membrane and net H(+) efflux from the cell, consistent with activation of the H(+)-ATPase. At the same time, net K(+) uptake occurs, and turgor increases (about 2-fold above normal levels). None of these changes are observed in the os-2 mutant (which lacks a functional MAP kinase, the last of the three kinases in the osmotic MAP kinase cascade). Tip growth ceases as hyperpolarization, net ion flux changes, and turgor increases begin. The inappropriate turgor increase is the probable cause of eventual lysis and death. The results corroborate a multi-pathway response to hyperosmotic stress that includes activation of plasma membrane transport. The relation to cell expansion (tip growth) is not direct. Increases in turgor due to ion transport might be expected to increase growth rate, but this does not occur. Instead, there must be a complex regulatory interplay between the growth and the turgor driving force, possibly mediated by regulation of cell wall extensibility.

Ptk2 contributes to osmoadaptation in the filamentous fungus Neurospora crassa.

Hyphal tip-growing organisms often rely upon an internal hydrostatic pressure (turgor) to drive localized expansion of the cell. Regulation of the turgor in response to osmotic shock is mediated primarily by an osmotic MAP kinase cascade which activates osmolyte synthesis and ion uptake to effect turgor recovery. We characterized a Neurospora crassa homolog (PTK2) of ser/thr kinase regulators of ion transport in yeast to determine its role in turgor regulation in a filamentous fungi. The ptk2 mutant is osmosensitive, and has lower turgor poise than wildtype. The cause appears to be lower activity of the plasma membrane H+-ATPase. Its role in osmoadaptation is unrelated to the activity of the osmotic MAP kinase cascade. Instead, it acts in an alternative pathway that, like the osmotic MAP kinase cascade, also involves ion transport mediated osmoadaptation.

Transient responses during hyperosmotic shock in the filamentous fungus Neurospora crassa.

Fungal cells maintain an internal hydrostatic pressure (turgor) of about 400-500 kPa. In the filamentous fungus Neurospora crassa, the initial cellular responses to hyperosmotic treatment are loss of turgor, a decrease in relative hyphal volume per unit length (within 1 min) and cell growth arrest; all recover over a period of 10-60 min due to increased net ion uptake and glycerol production. The electrical responses to hyperosmotic treatment are a transient depolarization of the potential (within 1 min), followed by a sustained hyperpolarization (after 4 min) to a potential more negative than the initial potential (a driving force for ion uptake). The nature of the transient depolarization was explored in the context of other transient responses to hyperosmotic shock, to determine whether activation of a specific ion permeability or some other rapid change in electrogenic transport was responsible. Changing the ionic composition of the extracellular medium revealed that K(+) permeability increases and H(+) permeability declines during the transient depolarization. We suggest that these changes are due to concerted inhibition of the electrogenic H(+)-ATPase, and an increase in a K(+) conductance. Knockout mutants of known K(+) (tok, trk, trm-8, hak-1) and Cl(-) (a clc-3 homologue) channels and transporters had no effect on the transient depolarization, but trk and hak-1 do play a role in osmoadaptation, as does a homologue of a serine kinase regulator of H(+)-ATPase in yeast, Ptk2.

Phenotype of a mechanosensitive channel mutant, mid-1, in a filamentous fungus, Neurospora crassa.

In the yeast Saccharomyces cerevisiae, the MID1 (mating-induced death) gene encodes a stretch-activated channel which is required for successful mating; the mutant phenotype is rescued by elevated extracellular calcium. Homologs of the MID1 gene are found in fungi that are morphologically complex compared to yeast, both Basidiomycetes and Ascomycetes. We explored the phenotype of a mid-1 knockout mutant in the filamentous ascomycete Neurospora crassa. The mutant exhibits lower growth vigor than the wild type (which is not rescued by replete calcium) and mates successfully. Thus, the role of the MID-1 protein differs from that of the homologous gene product in yeast. Hyphal cytology, growth on diverse carbon sources, turgor regulation, and circadian rhythms of the mid-1 mutant are all similar to those of the wild type. However, basal turgor is lower than wild type, as is the activity of the plasma membrane H(+)-ATPase (measured by cyanide [CN(-)]-induced depolarization of the energy-dependent component of the membrane potential). In addition, the mutant is unable to grow at low extracellular Ca(2+) levels or when cytoplasmic Ca(2+) is elevated with the Ca(2+) ionophore A23187. We conclude that the MID-1 protein plays a role in regulation of ion transport via Ca(2+) homeostasis and signaling. In the absence of normal ion transport activity, the mutant exhibits poorer growth.

Ionic currents and ion fluxes in Neurospora crassa hyphae.

Voltage dependence of ionic currents and ion fluxes in a walled, turgor-regulating cell were measured in Neurospora crassa. The hyphal morphology of the model organism Neurospora simplifies cable analysis of ionic currents to determine current density for quantitative comparisons with ion fluxes. The ion fluxes were measured directly and non-invasively with self-referencing ion-selective microelectrodes. Four ions (H(+), Ca(2+), K(+), and Cl(-)) were examined. H(+) net uptake and Ca(2+) net release were small (10.2 nmol m(-2) s(-1) and 1.1 nmol m(-2) s(-1), respectively) and voltage independent. K(+) and Cl(-) fluxes were larger and voltage dependent. Maximal K(+) net release ( approximately 1440 nmol m(-2) s(-1)) was observed at positive voltages (+15 mV), while maximal Cl(-) net release ( approximately 905 nmol m(-2) s(-1)) was observed at negative voltage (-210 mV). A possible function of the net outward K(+) and Cl(-) fluxes is regulation of the plasma membrane potential. Total ion fluxes were 37-58% of the total ionic current density (about +/-244 mA m(-2), equivalent to +/-2500 nmol m(-2) s(-1), at 0 mV and -200 mV) so other ions must contribute significantly to the ionic currents.

Turgor regulation in the osmosensitive cut mutant of Neurospora crassa.

The internal hydrostatic pressure (turgor) of fungal cells is maintained at 400-500 kPa. The turgor is regulated by changes in ion flux and by production of the osmotically active metabolite glycerol. In Neurospora crassa, there are at least two genetically distinct pathways that function in adaptation to hyperosmotic shock. One involves a mitogen-activated protein (MAP) kinase cascade (kinases OS-4, OS-5 and OS-2 downstream of the osmosensing OS-1); the other is less understood, but involves the cut gene, which encodes a putative phosphatase. This study examined turgor regulation, electrical responses, ion fluxes and glycerol accumulation in the cut mutant. Turgor recovery after hyperosmotic treatment was similar to that in the wild-type, for both time-course ( approximately 40 min) and magnitude. Prior to turgor recovery, the hyperosmotic shock caused a rapid transient depolarization of the membrane potential, followed by a sustained hyperpolarization that occurred concomitant with increased H(+) efflux, indicating that the plasma membrane H(+)-ATPase was being activated. These changes also occurred in the wild-type. Net fluxes of Ca(2+) and Cl(-) during turgor recovery were similar to those in the wild-type, but K(+) influx was attenuated in the cut mutant. The similar turgor recovery can be explained by the ion uptake, since glycerol did not accumulate in the cut mutant within the time frame of turgor recovery (but did accumulate in the wild-type). The results suggest that turgor regulation involves multi-faceted coordination of both ion flux and glycerol accumulation. Ion uptake is activated by a MAP kinase cascade, while CUT is required for glycerol accumulation.