Assessing the Utility of Toe Arm Index and Toe Pressure in Predicting Wound Healing in Patients Undergoing Vascular Intervention.

BACKGROUND: Objective measures of perfusion such as an ankle-brachial index (ABI) and toe pressure remain important in prognosticating wound healing. However, the use of ABI is limited in patients with incompressible vessels and toe pressure may not be comparable across patients. While a toe arm index (TAI) may be of value in this setting, its role as clinical indicator of perfusion for healing in patients with lower-extremity wounds has not been well established. METHODS: A retrospective review was performed of all vascular patients with lower-extremity wounds that underwent peripheral vascular intervention between 2014-2019. Data regarding patient demographics, comorbidities, TAI, ABI, toe pressures, and the wound, ischemia, and foot infection (WIfI) score were collected. Associations between patient variables and wound healing at various time points were evaluated. RESULTS: A total of 173 patients (67.7 ± 10.9 years; 71.1% male) were identified with lower-extremity wounds. Most patients underwent endovascular intervention (77.5%). Patients were followed for a median of 416 (IQR 129-900) days. Mean postoperative TAI was 0.35 ± 0.19 and mean WIfI score was 2.60 ± 1.17. Nine percent (15) of patients healed within 1 month, 44.8% (69) healed within 6 months, and 65.5% (97) healed within 1 year of revascularization without need for major amputation. Those that healed within 1 year without any major amputation did not differ from those that did not heal based on age, gender, race, comorbidities, periprocedural medications, or procedures performed. However, patients that healed without major amputation had a higher postoperative TAI (0.38 vs. 0.30, P = 0.02), higher toe pressure (53 vs. 40 mm Hg, P = 0.004), and lower WIfI score (2.26 vs. 3.12, P < 0.001). Patients that healed with 1 year without requiring any amputation had similar associations with postoperative TAI, toe pressure, and WIfI. Additionally, they were more likely to be White (P = 0.019) and have an open surgical procedure (P < 0.001) and less likely to have chronic kidney disease (P = 0.001) or diabetes (P = 0.008). A Youden index was calculated and identified a TAI value of 0.30 that optimized sensitivity and specificity for wound healing. The area under the curve for TAI as a predictor of wound healing was 0.62. CONCLUSIONS: Higher postoperative TAI is associated with higher odds of wound healing without need for major amputation. Toe arm index is therefore a useful tool to identify patients with adequate arterial perfusion to heal lower-extremity wounds. However, the area under the curve is poor for TAI when used as a sole predictor of wound healing potential suggesting that TAI should be one of multiple factors to considered when prognosticating wound healing potential.

Evidence for the additive effects of dispositional negative mood regulation expectancies and placebo-induced expectancies on mood recovery.

OBJECTIVE: Low negative mood regulation expectancies (NMRE) are associated with greater anticipated and experienced negative mood states, as well as with coping strategies that prolong these states. Individuals with low NMRE may be especially responsive to placebos because confidence in an external source of mood improvement can provide the positive mood expectancies and motivation for active coping that they typically lack. This study investigated how NMRE and placebo-induced expectancies contribute to mood recovery. METHOD: Participants (N = 125) completed personality scales, including NMRE, online. During a subsequent in-person session, participants were randomly assigned to one of three conditions: (1) placebo treatment-participants learned of a mood-enhancing treatment and received it; (2) treatment deprivation-participants learned of the same treatment, but did not receive it; (3) control-treatment was never mentioned. Participants also completed measures of mood, active coping, and expectations. RESULTS: NMRE was a stronger predictor of mood recovery than placebo-induced expectancies regardless of group assignment. Additionally, pessimistic expectations arose when participants believed treatment was being deprived, and these participants exhibited the least active coping. CONCLUSION: Our results confirm the reliability of NMRE in predicting affective outcomes and suggest that personality and placebo-induced expectations have additive effects on mood recovery.

Modeling Driving Performance Using In-Vehicle Speech Data From a Naturalistic Driving Study.

OBJECTIVE: We aimed to (a) describe the development and application of an automated approach for processing in-vehicle speech data from a naturalistic driving study (NDS), (b) examine the influence of child passenger presence on driving performance, and (c) model this relationship using in-vehicle speech data. BACKGROUND: Parent drivers frequently engage in child-related secondary behaviors, but the impact on driving performance is unknown. Applying automated speech-processing techniques to NDS audio data would facilitate the analysis of in-vehicle driver-child interactions and their influence on driving performance. METHOD: Speech activity detection and speaker diarization algorithms were applied to audio data from a Melbourne-based NDS involving 42 families. Multilevel models were developed to evaluate the effect of speech activity and the presence of child passengers on driving performance. RESULTS: Speech activity was significantly associated with velocity and steering angle variability. Child passenger presence alone was not associated with changes in driving performance. However, speech activity in the presence of two child passengers was associated with the most variability in driving performance. CONCLUSION: The effects of in-vehicle speech on driving performance in the presence of child passengers appear to be heterogeneous, and multiple factors may need to be considered in evaluating their impact. This goal can potentially be achieved within large-scale NDS through the automated processing of observational data, including speech. APPLICATION: Speech-processing algorithms enable new perspectives on driving performance to be gained from existing NDS data, and variables that were once labor-intensive to process can be readily utilized in future research.

Priming a natural or human-made environment directs attention to context-congruent threatening stimuli.

Research suggests that attention is attracted to evolutionary threats (e.g., snakes) due to an evolved "fear-module" that automatically detects biological threats to survival. However, recent evidence indicates that non-evolutionary threats (e.g., guns) capture and hold attention as well, suggesting a more general "threat-relevance" mechanism that directs attentional resources toward any potential danger in the environment. The current research measured how selective attentional resources were influenced both by the type of threat (e.g., snake vs. gun) and by the context in which the threat was encountered. Participants were primed with either natural or human-made environments to assess how these contexts influence attention to evolutionary and non-evolutionary threats, as measured by a spatial-cueing task. The results indicate that whether biological or non-biological threats receive greater attentional processing is determined by the context in which they are encountered.

Growth motivation as a moderator of behavioral self-handicapping in women.

Behavioral self-handicapping is a strategy used to protect attributions about ability. People behaviorally self-handicap by creating an obstacle to their success so failure is attributed to the obstacle instead of to their ability. Although past research has observed behavioral self-handicapping exclusively in men, the current research revealed a moderator of behavioral self-handicapping in women: growth motivation, which reflects the desire to develop one's abilities and learn from failure. Participants (N = 100) completed a test purportedly predictive of successful careers and relationships, and some were given failure feedback about their performance. Participants could behaviorally self-handicap by choosing to complete another test in a performance-impairing environment. Although men self-handicapped more overall, women self-handicapped more after failure when they were low in growth motivation. These results highlight a novel moderator of behavioral self-handicapping in women.

Fan cells in lateral entorhinal cortex directly influence medial entorhinal cortex through synaptic connections in layer 1.

Standard models for spatial and episodic memory suggest that the lateral entorhinal cortex (LEC) and medial entorhinal cortex (MEC) send parallel independent inputs to the hippocampus, each carrying different types of information. Here, we evaluate the possibility that information is integrated between divisions of the entorhinal cortex prior to reaching the hippocampus. We demonstrate that, in mice, fan cells in layer 2 (L2) of LEC that receive neocortical inputs, and that project to the hippocampal dentate gyrus, also send axon collaterals to layer 1 (L1) of the MEC. Activation of inputs from fan cells evokes monosynaptic glutamatergic excitation of stellate and pyramidal cells in L2 of the MEC, typically followed by inhibition that contains fast and slow components mediated by GABAA and GABAB receptors, respectively. Inputs from fan cells also directly activate interneurons in L1 and L2 of MEC, with synaptic connections from L1 interneurons accounting for slow feedforward inhibition of L2 principal cell populations. The relative strength of excitation and inhibition following fan cell activation differs substantially between neurons and is largely independent of anatomical location. Our results demonstrate that the LEC, in addition to directly influencing the hippocampus, can activate or inhibit major hippocampal inputs arising from the MEC. Thus, local circuits in the superficial MEC may combine spatial information with sensory and higher order signals from the LEC, providing a substrate for integration of 'what' and 'where' components of episodic memories.

Deep entorhinal cortex: from circuit organization to spatial cognition and memory.

The deep layers of the entorhinal cortex are important for spatial cognition, as well as memory storage, consolidation and retrieval. A long-standing hypothesis is that deep-layer neurons relay spatial and memory-related signals between the hippocampus and telencephalon. We review the implications of recent circuit-level analyses that suggest more complex roles. The organization of deep entorhinal layers is consistent with multi-stage processing by specialized cell populations; in this framework, hippocampal, neocortical, and subcortical inputs are integrated to generate representations for use by targets in the telencephalon and for feedback to the superficial entorhinal cortex and hippocampus. Addressing individual sublayers of the deep entorhinal cortex in future experiments and models will be important for establishing systems-level mechanisms for spatial cognition and episodic memory.

Seasonal variation in North American level crossing crash rates is due to weather, not day length.

OBJECTIVE: Collisions between road vehicles and trains at level (grade) crossings can be devastating. Injury and economic considerations make prevention efforts of significant interest to society at all levels, and raise important safety concerns. Improving our understanding of the nature and pattern of crashes at level crossings can help inform a variety of types of safety mitigation strategies, including public education, crossing equipment and vehicle design efforts. METHOD: To this end, a database search of Canadian level crossing crashes for the 11-year period between 2007 and 2017 was conducted to confirm a previously identified seasonal variation in the frequency of level crossing crashes. To determine whether the observed winter increase in crashes was due primarily to winter reductions in light levels/day length or to other seasonal weather factors, a subsequent comparison of Canadian data to American Federal Railroad Administration (FRA) crash data was carried out. A separate inferential log-linear model analysis, using season, time of day and crossing protection type, was also used to explore the increase. RESULTS: As expected, the average rate of crossing collisions in Canada increased during winter months compared to non-winter months. While the seasonal pattern was evident in those U.S. states that experience significant changes in weather patterns (i.e., northern states), it was almost completely absent in those states that do not (i.e., southern states). The log-linear model analysis confirmed these findings. CONCLUSIONS: The seasonal variation in North American level crossing crash rate is a result of winter weather conditions, rather than differences in light levels. Future research is planned that will elucidate the specific environmental and human factors contributing to the increase.

Applying principles of fatigue science to accident investigation: Transportation Safety Board of Canada (TSB) fatigue investigation methodology.

Fatigue that is related to the amount and quality of sleep obtained can impair human performance in ways that can lead to accidents. As many transportation industries operate around the clock, fatigue and its effects cannot be eliminated completely; instead, they must be managed. A first step is to document the prevalence and role of fatigue in accidents that occur. The Transportation Safety Board of Canada (TSB) routinely investigates such transportation industry incidents to determine if fatigue was present, if it played a role, and if there were practices in place to effectively manage it and associated risks. Herein, we summarize and describe the TSB's fatigue investigation methodology in the hopes that investigators of other organizations and domains will find the concepts applicable to their operational context.

When chronic isn't chronic: the moderating role of active self-aspects.

The current work considered how self-concept organization moderates the consequences of chronic attributes, which are widely assumed to be always accessible and influential. In Study 1, the accessibility of participants' chronic attributes was assessed before and after activating a self-aspect that was either relevant or irrelevant to participants' chronic attributes. Results showed that chronic attributes were more accessible when they were relevant to a participant's active self-aspect than when they were irrelevant to it. In Study 2, participants read ambiguous behaviors performed by others, some of which could be interpreted in line with their own chronic attribute or an alternative attribute. Participants were more likely to interpret behaviors as consistent with their own chronic attributes, but only when a relevant self-aspect had been previously activated. These studies suggest that chronicity can be moderated by self-aspect activation, consistent with the perspective that the self consists of multiple, context-dependent self-aspects.

The simple life: on the benefits of low self-complexity.

This article examines the spillover amplification hypothesis, which proposes that because people lower in self-complexity experience stronger responses to life events they will show relatively better well-being in the presence of positive factors (e.g., better social support) and relatively poorer well-being in the presence of negative factors (e.g., a history of negative experiences). Across three studies, support for spillover amplification was found. Specifically, people lower in self-complexity revealed greater self-esteem, less depression, and fewer illnesses when they had greater social support (Study 1) and more desirable personality characteristics (Study 2), yet they had poorer well-being if they had a history of many negative life events (Study 3). Thus, how one's self-concept is represented in memory moderates the relationship between many well-established factors and well-being.

Personal, interpersonal, and situational influences on behavioral self-handicapping.

This study explored the combined effects of personal factors (participant sex), interpersonal factors (experimenter sex), and situational factors (performance feedback) on two forms of behavioral self-handicapping. Participants received non-contingent success or failure feedback concerning their performance on a novel ability and were given the opportunity to self-handicap before performing again. Behavioral self-handicapping took the form of (a) exerting less practice effort (practice) or (b) choosing a performance-debilitating tape (choice). Men practiced least after failure feedback and chose a debilitating tape if they were interacting with a female experimenter. Generally, across all participants in both choice and practice conditions, high performance concern and the presence of a male experimenter led to the most self-handicapping. Results are interpreted in terms of self-presentational concerns that emphasize a desire to impress or an awareness of the female or male experimenter's acceptance of self-handicappers.

How shift scheduling practices contribute to fatigue amongst freight rail operating employees: Findings from Canadian accident investigations.

Canada's freight rail system moves 70% of the country's surface goods and almost half of all exports (RAC, 2016). These include dangerous goods. Anonymous survey of freight rail operating employees conducted by the Teamsters Canada Rail Conference (TCRC, 2014) revealed that many do not report getting enough sleep because of their work schedules, and that fatigue may be affecting their performance at work. Besides general impairments in attention and cognitive functioning, fatigue in railway operating employees slows reaction time to safety alarms and impairs conformance to train operating requirements. Shift scheduling practices can contribute to sleep-related fatigue by restricting sleep opportunities, requiring extended periods of wakefulness and by disrupting daily (circadian) rhythms. The primary goal of accident investigation is to identify causal and contributing factors so that similar occurrences can be prevented. A database search of Transportation Safety Board (TSB) rail investigation reports published in the 21-year period from 1995 to 2015 identified 18 that cited sleep-related fatigue of freight rail operating employees as a causal, contributing, or risk finding. This number represents about 20% of TSB rail investigations from the same period in which a human factors aspect of freight train activities was a primary cause. Exploration of accident themes suggests that management of fatigue and shift scheduling in the freight rail industry is a complex issue that is often not conducive to employee circadian rhythms and sleep requirements. It also suggests that current shift scheduling and fatigue management practices may be insufficient to mitigate the associated safety risk. Railway fatigue management systems that are based on the principles of modern sleep science are needed to improve scheduling practices and mitigate the ongoing safety risk.

The common characteristics and behaviors of child occupants in motor vehicle travel.

Objective: Child occupant behavior and head position when travelling in child restraint systems (CRS) may have an effect on injury risk in the event of a motor vehicle crash. The current study aimed to describe the common characteristics and behaviors of child occupants during everyday, real-world motor vehicle travel in a sample of Australian families to identify potential safety implications of observed behaviors and head position within the CRS. Methods: Two instrumented study vehicles were used by 42 families for approximately two weeks. Continuous video and audio data were collected across 1,651 trips (over 600 hours). An online survey provided additional parent, familial and child occupant data. The characteristics and behaviors of 72 child occupants (aged 14 months to 9 years) who travelled in a forward-facing CRS (FFCRS) or a belt-positioning booster seat (BS) were observed and recorded by manual review of a sample of the video/audio recordings. One quarter of all trips (n = 414) was randomly selected for coding/analysis and, within each trip, one child occupant was selected who was travelling in a FFCRS or BS. Child occupant behaviors, head position within the FFCRS or BS, and other relevant information was coded for each trip during nine discrete five second intervals or 'epochs' (5%, 17%, 25%, 30%, 50%, 53%, 75%, 89% and 95% of trip duration). Results: In the majority of epochs (74%), child occupants' heads were observed to be 'optimally' positioned within the FFCRS or BS. For more than half of the epochs, child occupants were observed to be: correctly restrained (58%) and involved in an interaction with another vehicle occupant (59%). Bivariate analyses revealed that children travelling in a FFCRS were significantly more likely to be observed to have optimal head positions than those travelling in a BS (78% vs. 62%), χ2 (1) = 86.00, p < 0.001. Child occupants who were observed to be 'correctly' restrained were significantly more likely to be observed to have optimal head positions than those who were observed to be 'incorrectly' restrained (80% vs. 20%), χ2 (1) = 10.33, p < 0.01. Conclusions: This is the first naturalistic driving study (NDS) to specifically explore the factors associated with child occupants' head position when travelling in a CRS. Findings from the current study can be used to inform the positioning of anthropometric test dummies (ATD) in CRS testing, guide improvements to CRS/vehicle design, and develop targeted educational strategies to improve child occupant safety.

Standardized error severity score (ESS) ratings to quantify risk associated with child restraint system (CRS) and booster seat misuse.

OBJECTIVE: Although numerous research studies have reported high levels of error and misuse of child restraint systems (CRS) and booster seats in experimental and real-world scenarios, conclusions are limited because they provide little information regarding which installation issues pose the highest risk and thus should be targeted for change. Beneficial to legislating bodies and researchers alike would be a standardized, globally relevant assessment of the potential injury risk associated with more common forms of CRS and booster seat misuse, which could be applied with observed error frequency-for example, in car seat clinics or during prototype user testing-to better identify and characterize the installation issues of greatest risk to safety. METHODS: A group of 8 leading world experts in CRS and injury biomechanics, who were members of an international child safety project, estimated the potential injury severity associated with common forms of CRS and booster seat misuse. These injury risk error severity score (ESS) ratings were compiled and compared to scores from previous research that had used a similar procedure but with fewer respondents. To illustrate their application, and as part of a larger study examining CRS and booster seat labeling requirements, the new standardized ESS ratings were applied to objective installation performance data from 26 adult participants who installed a convertible (rear- vs. forward-facing) CRS and booster seat in a vehicle, and a child test dummy in the CRS and booster seat, using labels that only just met minimal regulatory requirements. The outcome measure, the risk priority number (RPN), represented the composite scores of injury risk and observed installation error frequency. RESULTS: Variability within the sample of ESS ratings in the present study was smaller than that generated in previous studies, indicating better agreement among experts on what constituted injury risk. Application of the new standardized ESS ratings to installation performance data revealed several areas of misuse of the CRS/booster seat associated with high potential injury risk. CONCLUSIONS: Collectively, findings indicate that standardized ESS ratings are useful for estimating injury risk potential associated with real-world CRS and booster seat installation errors.

The effect of driver eye height on speed choice, lane-keeping, and car-following behavior: results of two driving simulator studies.

OBJECTIVE: Two simulator studies were conducted that assessed the effect of driver eye height on speed choice, lane-keeping, and car-following behavior. The effect of eye height on the subjective variables of mental workload, frustration, and confidence was also investigated, as was the contribution of drivers' aggression. METHODS: A total of 43 participants drove a simulated route while seated at two different eye heights: one that represented the view of the road from a large SUV and one that represented the view of the road from a small sports car. Driving scenarios were comprised of both open road and car-following segments. Dependent variables included driver-selected speed, speed variability, lane position, following distance to a slower-moving lead vehicle, and the subjective variables of frustration, confidence, and mental workload. RESULTS: When viewing the road from a high eye height, drivers drove faster, with more variability, and were less able to maintain a consistent position within the lane than when viewing the road from a low eye height. Driver eye height did not influence following distance to a slower-moving lead vehicle. Driver aggression had no effect on any of the dependent variables except level of frustration. CONCLUSIONS: The two studies demonstrate that, when they are not able to reference a speedometer, drivers choose to drive faster when they view the road from an eye height that is representative of a large SUV compared to that of a small sports car. There is a need to educate drivers of SUVs and other tall vehicles of this perceptual phenomenon in order to prevent collisions that may occur in conditions where it is impossible for drivers to base their speed selection solely on posted speed limits, such as in inclement weather.

Functional flexibility in women's commitment-skepticism bias.

If a woman overestimates her romantic partner's commitment, the cost to her fitness-reproduction without an investing partner-can be considerable. Error Management Theory predicts that women have an evolved bias to be skeptical of men's commitment in a relationship, which reduces the likelihood of making a costly false positive error. However, because error probabilities are inversely related, this commitment-skepticism bias simultaneously increases the likelihood of missed opportunities, or false negatives. False positives when gauging a partner's commitment are the more costly error for women, but missing an opportunity to secure a genuinely high-quality mate can also be quite costly. We predicted and found that women's mating cognitions are functionally flexible, such that women do not exhibit the commitment-skepticism bias when faced with behavioral evidence that a male partner is willing to commit (Study 1). This suggests that relationship-enhancing behaviors are one contextual cue that may lessen the bias. However, not all relationship-enhancing behaviors are equally diagnostic of a person's true commitment intent. When comparing men and women's commitment thresholds, we found that women require more behavioral evidence than men do to feel certain of their partner's commitment to them (Study 2).

Gender Differences in the Social Cost of Affective Deviance.

The current study tested whether men and women receive different degrees of social punishment for violating norms of emotional expression. Participants watched videos of male and female targets (whose reactions were pre-tested to be equivalent in expressivity and valence) viewing either a positive or negative slideshow, with their emotional reaction to the slideshow manipulated to be affectively congruent, affectively incongruent, or flat. Participants then rated the target on a number of social evaluation measures. Displaying an incongruent emotional expression, relative to a congruent one, harmed judgments of women more than men. Women are expected to be more emotionally expressive than men, making an incongruent expression more deviant for women. These results highlight the importance of social norms in construing another person's emotion displays, which can subsequently determine acceptance or rejection of that person.

Evaluation of a video-based measure of driver heart rate.

INTRODUCTION: Internal driver events such as emotional arousal do not consistently elicit observable behaviors. However, heart rate (HR) offers promise as a surrogate measure for predicting these states in drivers. Imaging photoplethysmography (IPPG) can measure HR from face video recorded in static, indoor settings, but has yet to be examined in an in-vehicle driving environment. METHODS: Participants (N=10) completed an on-road driving task whilst wearing a commercial, chest-strap style heart rate monitor ("baseline"). IPPG was applied to driver face video to estimate HR and the two measures of HR were compared. RESULTS: For 4 of 10 participants, IPPG produced a valid HR signal (±5 BPM of baseline) between 48 and 75% of trip duration. For the remaining participants, IPPG accuracy was poor (<20%). CONCLUSIONS: In-vehicle IPPG is achievable, but significant challenges remain. PRACTICAL APPLICATIONS: The relationship between IPPG accuracy and various confounding factors was quantified for future refinement.