Operational Stress Research Articles

Brief mindfulness training for Canadian public safety personnel well-being

The body of research demonstrating the psychological and physiological benefits of mindfulness-based interventions (MBIs) is robust and spans decades, yet its adaptation for a population at significantly higher-than-average risk of negative health outcomes, operational stress injuries, moral injury, and burnout is in its infancy. Failing to address these risks has costs not just for the well-being of public safety professionals (PSPs), but for their families, their agencies, and their communities. Public safety work requires a high standard of ethical decision-making and compassionate contact with the communities served. The public safety oversight of agency, government, and training institutes must prepare its professionals to deliver exemplary levels of service as well as establish trauma-competent training and support frameworks that are evidence-based to protect PSP well-being. Remedying historically ineffective training with evidence-based models not only addresses the complexity of operational stress injuries (OSIs) but also the needs of social justice reform. Canada’s contribution to the body of research using evidence-based MBIs for PSP well-being is scarce. This literature review informs leaders, policymakers, change agents, and researchers not only of the need for such critical research in Canada, but of its current state and important considerations for its design. The efficacy of MBI is discussed, evaluating recent quantitative, qualitative, and mixed-methods studies towards charting a brief MBI (bMBI) logistically deliverable, attentive to the PSP cultural context needs and barriers, and which facilitates sustainable skill-building in attention, awareness, and compassion.

Frequency and costs of low-value preoperative tests for patients undergoing low-risk procedures in the veterans health administration

BackgroundClinical practice guidelines discourage routine preoperative screening tests for patients undergoing low-risk procedures. This study sought to determine the frequency and costs of potentially low-value preoperative screening tests in Veterans Health Administration (VA) patients undergoing low-risk procedures.MethodsUsing the VA Corporate Data Warehouse, we identified Operative Stress Score class 1 procedures (“very minor”) performed without general anesthesia in VA during fiscal year 2019 and calculated the overall national and facility-level rates and costs of nine common tests received in the 30 preoperative days. Patient factors associated with receiving at least one screening test, and the number of tests received, were examined.ResultsEighty-six thousand three hundred twenty-seven of 178,775 low-risk procedures (49.3%) were preceded by 321,917 potentially low-value screening tests representing $11,505,170 using Medicare average costs. Complete blood count was the most common (33.2% of procedures), followed by basic metabolic profile (32.0%), urinalysis (26.3%), electrocardiography (18.9%), and pulmonary function test (12.4%). Older age, female sex, Black race, and having more comorbidities were associated with higher odds of low-value testing. Transthoracic echocardiogram occurred prior to only 4.5% of the procedures but accounted for 47.8% of the total costs ($5,499,860). In 129 VA facilities, the facility-level proportion of procedures preceded by at least one test ranged from 0 to 81.2% and facility-level costs ranged from $0 to $388,476.ConclusionsRoutine preoperative screening tests for very low-risk procedures are common and costly in some VA facilities. These results highlight a potential target to improve quality and value by reducing unnecessary care. Measures of low-value perioperative care could be integrated into VA’s extensive quality monitoring and improvement infrastructure.

Solving the challenging puzzle of the Grimsel II runner vibration

After 30 years of operation, the runners of the four 100 MW high-head Francis turbines successively developed fatigue cracks starting from the hub-side trailing-edge fillets. Assessment of alternating stress in normal turbine operation revealed that stress levels were not nearly large enough to explain the damages. Consequently, a test campaign comprising start and stop manoeuvres in addition to normal turbine operation was conducted in 2017. Strain gauge signals obtained on-board of the runner blades were recorded together with casing vibration and acoustic signals. Intense high-frequency vibration centred around 611 Hz was detected in three transient conditions of operation: at speed-no-load (SNL), during coast-down and during back-to-back pump start. Common properties of these conditions were very low to no discharge, strong secondary flow in the runner and speed between 50 and 100 %. Due to the extremely narrow bandwidth, three possible ways of excitation were considered and checked: rotor-stator interaction (RSI), rotor-dynamic instability and Von Kármán excitation. RSI was excluded due to speed-independent frequency. Strong sidebands in the stationary-frame frequency spectra - obviously caused by runner shroud deformation shapes ND1 through ND5 - excluded any feedback from runner side chamber pressure; thus leaving Von Kármán excitation as the only possible diagnosis. Accordingly, a very safe profile was selected and implemented for the runner blade trailing edges. Subsequent field-testing at two modified units confirmed that the vibration problem at the harmful operation points had hereby been eliminated.

Slow Wave Activity Sleep Is Significantly Associated With Decision-making During Simulated Military Operational Stress

Slow Wave Activity Sleep Is Significantly Associated With Decision-making During Simulated Military Operational Stress

A New Instrument For Operational Stress Assessment

Abstract This paper aims to be an overview of the scientific approach on the development of an inventory of operational stress assessment, specific to the military operations theatre, in order to make it available to practicing psychologists. Conclusive scientific data and evidence have been obtained from empirical studies over several years, and the resulting tool can be used with confidence.

Utility Of Extracellular Vesicles As A Biological Indicator Of Physiological Resilience During Military Operational Stress

Utility Of Extracellular Vesicles As A Biological Indicator Of Physiological Resilience During Military Operational Stress

Perception-action Coupling Impairments During Simulated Military Operational Stress Are Dependent On Time-of-day

Perception-action coupling (i.e., reading and reacting to the environment) allows military personnel to maneuver safely and effectively through their environment. Exposure to military operational stress (e.g., caloric restriction, sleep loss) and around-the-clock operations may compromise perception-action coupling thereby impacting performance and safety. PURPOSE: To examine the effects of simulated military operational stress (SMOS) and time-of-day on perception-action coupling. METHODS: Fifty-seven military personnel (45 M, 12 W; 26.4 ± 5.6 years) completed a 5-day SMOS protocol. On day 0 (D0), D1 and D4, participants had 8-hour sleep opportunities and received 100% estimated caloric need. On D2 and D3, sleep was restricted and disrupted (two 2-hour sleep opportunities from 01:00 - 03:00 and 05:00 - 07:00), and caloric intake was restricted (50% estimated caloric need). Participants completed a tablet-based perception-action coupling task (PACT) on D1 (18:00, 22:00), D2 (04:00, 18:00, 22:00) and D3 (04:00, 18:00, 22:00). PACT requires participants make perceptual judgements about whether a series of virtual balls fits through virtual apertures of varying sizes. Outcomes of interest included response time (RT), lapses, and incorrect responses. Effects of day X time, day and time were examined using linear mixed models with post hoc pairwise comparisons (Tukey correction). RESULTS: Significant day X time effects were found for RT and lapses (both p < .01) and a significant effect of time was found for incorrect responses (p = .01). RT at 04:00 increased (got slower) by 2.2% across days, but decreased (got faster) by 6.8 and 3.5% across days at 18:00 and 22:00. Lapses at 04:00 increased across days but did not differ from D1 to D3 at 18:00 and 22:00. Participants made 39.3 and 6.0% more incorrect responses at 04:00 than at 18:00 and 22:00 respectively. CONCLUSIONS: Perception-action coupling performance was resilient to SMOS at 18:00 and 22:00, but deteriorated at 04:00. Reduced alertness (lapses), inaccurate perceptual judgements (incorrect responses), and slower response execution (RT) all contributed to perception-action coupling deficits at 04:00 which may reflect impaired performance capabilities of military personnel operating around-the-clock in the field. Support: DoD #W81XWH-17-2-0070

Outcome metrics utilized in evaluations of programs and interventions for combat and operational stress: A review of psychometric properties

ABSTRACT The Department of Defense has mandated combat and operational stress control (COSC) efforts for the Services since 1999. Although several COSC-related programs have been implemented, few have undergone evaluation, and no standardized metrics have been established to assess their effectiveness and utility. The purpose of this review was to characterize the content and psychometrics of measures that have been utilized as outcome metrics in evaluations of COSC-related programs and interventions. Systematic literature searches were conducted for publications that: a) evaluated at least one measure from U.S. service members who participated in a program or intervention to prevent or reduce the adverse effects of combat and operational stress; and b) reported U.S. data on the internal consistency, test-retest reliability, convergent validity, and sensitivity/specificity of the identified measures. This process identified 15 measures for which psychometric properties were reviewed for acceptability based on recommended criteria. Identified measures varied from well-validated measures to newer instruments for which more data is needed on one or more of the target psychometric properties. Aside from internal consistency, psychometric data from U.S. military samples were sparse. Results further suggested that some measures might have reduced sensitivity in service members under certain conditions, such as large-scale screening. Additional studies are needed to validate COSC-relevant measures in service members. Future evaluations of programs and interventions for combat and operational stress should select measures that will increase the consistency of the literature, allow comparisons across studies, and ensure alignment with the objectives of identified programs.

The impact of data sonification in virtual reality robot teleoperation

Virtual Reality (VR) is being increasingly used to provide a more intuitive and embodied approach to robotic teleoperation, giving operators a sense of presence in the remote environment. Prior research has shown that presence can be enhanced when additional sensory cues such as sound are introduced. Data sonification is the use of non-speech audio to convey information and, in the context of VR robot teleoperation, it has the potential to 1) improve task performance by enhancing an operator’s sense of presence and 2) reduce task load by spreading data between sensory modalities. Here we present a novel study methodology to investigate how the design of data sonification impacts on these important metrics and other key measures of user experience, such as stress. We examine a nuclear decommissioning application of robotic teleoperation where the benefits of VR in terms of spatial reasoning and task performance are desirable. However, as the operational environment is hazardous, a sense of presence may not be desirable as it can lead to heightened operator stress. We conduct a study in which we compare the effects of diegetic sounds (literal and established sonifications) with abstract sounds (non-established sonifications). Our findings show that the diegetic sounds decrease workload, whereas abstract sounds increase workload, and are more stressful. Additionally, and contrary to expectations, sonification does not impact presence. These findings have implications for the design of sonic environments in virtual reality.

The History and Development of the Percutaneous Pedicle Screw (PPS) System.

Minimally invasive transforaminal lumbar interbody fusion (MIS-TLIF) using the SEXTANT® system (Medtronic) featured the first generation of commercially available percutaneous pedicle screw (PPS) system in 2001. The innovative system has since become standard instrumentation used worldwide, and PPS is now used for long-segment minimally invasive surgery (MIS) spinal fixation from the thoracic spine to the pelvis for pathological conditions. PPS systems have been developed for approximately 20 years for the purpose of improving minimally invasive techniques, safety of instrumentation, and ease of use. The third-generation PPS systems established the insertion technique, and the development of the fourth-generation PPS systems have made great strides in minimizing the number of steps in the operative procedure. In the future, PPS systems are expected to continue making use of the latest technological advancements and to develop further with the aim of ensuring greater safety, reducing operator stress, and preventing complications such as insertion errors and infection. In this review article, we describe the historical evolution from the first-generation PPS system to the current PPS systems used today.

The application of forward psychiatry among Malaysian soldiers on battlefield: Case Series

Introduction: The forward psychiatry practice in the combat field has proven effective in reducing the attrition rates due to combat and operational stress of the service members. The concept has evolved over the years with the same objective to conserve the fighting troops' strength and minimize the incident rates of post-traumatic stress disorder among the soldiers. The Combat and Operational Stress Reaction (COSR) team has been deployed to the conflict zone and applied the forward psychiatry principles to the troops on the battlefield. Case Series: Here, we presented 3 case series of service members that were attended by the COSR team during their deployment on the frontline. First, a serviceman presented with late recognition of acute stress symptoms following active combat duty with poor support from his unit. Second, a combat engineer presented with anxiety and somatic symptoms after combat duty; third, a combat radio operator with early detection of acute stress symptoms by his unit commander. Results: In the first case, the patient's psychological condition deteriorated, requiring frequent sedation and transfer to a military tertiary hospital. In the second and third cases, both patients improved and returned to their duties with individualized psychotherapy and relaxation techniques. Conclusion: Early detection of the symptoms and intervention based on the principles of forward psychiatry in active combat zone facilitate service members' return to function and reduce complications and morbidity to their psychological health. ASEAN Journal of Psychiatry Vol. 23(8) August, 2022; 1-11.

Comprehensive evaluation of fatigue damage accumulation and failure of specimens with operational stress concentrators

The paper presents the results of studying the mechanical behavior of laminated carbon-fiber-reinforced plastic under complex low-velocity impact three-point bending followed by cyclic tension. An integrated approach to studying damage accumulation patterns is implemented with the use of state-of-the-art testing and diagnostic equipment. The residual fatigue life of the composite is related to the intensity of preliminary impact bending. The fields of temperature distribution in the active zone of the samples during the tests are shown. Data on damage accumulation obtained by recording acoustic emission signals are presented. Relation of the change in the recorded acoustic response signals to infrared thermal scanning data has been detected, which is supported by the results of an experimental study. The use of additional equipment for infrared thermal scanning and recording of acoustic emission signals gives a complete picture of damage accumulation and failure in composite materials, with a good agreement with experimental data.

Factors and optimizations of healthcare workers' perception in alternative care facilities.

BackgroundDiverse measures have been carried out worldwide to establish Alternative Care Facilities (ACFs) for different ends, such as receiving, curing or isolating patients, aiming to cope with tremendous shock in the urban medical system during the early passage of the COVID-19 epidemic. Healthcare workers always felt anxious and stressed during multiple major public health emergencies in medical facilities. Some active measures to improve healthcare workers' perceptions, such as temporary training, workflow improvement, and supplementary facilities, were proved insufficient in several past public health emergencies. Therefore, this study aims to analyze the contributing factors of the healthcare workers' perceptions of the ACFs in this pandemic, which can help find an innovative path to ensure their health, well-being and work efficiency.MethodThis paper conducted semi-structured in-depth interviews with the world's first batch of healthcare workers who have worked in ACFs through a qualitative study based on Grounded Theory. The healthcare workers interviewed from Heilongjiang, Shandong, Fujian, and Hubei provinces, have worked in one of the four different ACFs built in Wuhan. The results are obtained through the three-level codes and analyses of the interview recordings.ResultsThe factors affecting the perception of healthcare workers in ACFs during the epidemic situation can be summarized into five major categories: individual characteristics, organization management, facilities and equipment, space design, and internal environment. The five major categories affecting the composition of perception can be further divided into endogenous and exogenous factors, which jointly affect the perception of healthcare workers in ACFs. Among them, individual characteristics belong to endogenous factors, which are the primary conditions, while other categories belong to exogenous factors, which are the decisive conditions.ConclusionThis paper clarifies factors affecting the perception of healthcare workers in ACFs and analyzes the mechanism of each factor. It is posited that the passive strategies are a promising solution to protect healthcare workers' health, improve their work efficiency, and help reduce the operation stress of ACFs. We should train multidisciplinary professionals for future healthcare and enhance collaborations between healthcare workers and engineers. To sum up, this paper broadens new horizons for future research on the optimization of ACFs and finds new paths for alleviating healthcare workers' adverse perceptions of ACFs.

Luminance stepped decreasing ratio of the tunnel entrance enhanced lighting based on visual performance.

To achieve a safe and comfortable entrance enhanced lighting environment of tunnels, visual performance experiments under the dynamic and static luminance environments were carried out to investigate the influence of the luminance variation forms and stepped decreasing ratio k' of the tunnel entrance enhanced lighting on the driver's comprehensive visual performance. The application effect was further verified by real vehicle experiments and field luminance measurements. The results of the dynamic and static experiments show that compared with the continuous and smooth decrease of the luminance according to the International Commission on Illumination (CIE), when facing the stepped decrease of luminance, drivers tend to withstand greater visual operation stress and a more tense psychological state. After the stepped decrease of the luminance, the driver's average and instantaneous reaction both slow down, while the amplitude of the slowdown decreases with the increase of k' and increases with the increase of the luminance level. The results of the real vehicle experiments show that increasing k' of Threshold Zones 1 and 2 and Transition Zones 1 and 2 to 0.7, 0.6, 0.5, and 0.5, respectively, can effectively relieve driver's psychological tension and enhance the visual performance. For practical engineering applications, it should be combined with daylight reduction facilities, thus avoiding the increase of energy consumption of the tunnel entrance enhance lighting.

Research on bearing capacity and sealing contact characteristics of the subsea wellhead connector

This paper analyzed the bearing capacity of a subsea wellhead connector when exposed to external pressure and the bending moment in different operational modes and load conditions to determine the possible areas prone to failure. The contact between certain parts during the pre-tightening process impacts other areas, affecting the sealing performance. A symmetrical, three-dimensional periodic contact model was established via Finite Element Method (FEM) to simulate and analyze the sealing performance of the subsea wellhead connector. Furthermore, this study examined the variation laws governing contact form, preload, contact width, radial compression, and internal pressure, as well as their influence on the contact stress of the metal sealing ring. The results indicated that effective sealing was achieved at radial compression levels ranging from 0.1045 to 0.2089 mm. The preload contact stress was directly proportional to the preload and radial compression and inversely proportional to the contact width. The operational contact stress initially decreased, then increased at a higher internal pressure.

A Post-Traumatic Growth Perspective on PTSD: Implications for Those Who Have Served and Their Partners

Research emphasizing the negative psychosocial impacts of service-related post-traumatic stress disorder (PTSD) for military members, veterans, and their families is well established. Post-traumatic growth (PTG), positive psychological change resulting from managing adverse life events and situations, is an alternate outcome considered in research focusing on the impacts of serious illness and other life-altering circumstances on families. Little is known, however, about the processes that create and sustain PTG within military and veteran family systems. This paper will review conceptualizations of PTG and consider its relevance as a construct for analysis of outcomes related to the experiences of partners of military members and veterans living with PTSD and other operational stress injuries.

A Study of Stress Evolution and Deformation in Cylindrical Cells, from before Manufacturing to End of Life

The mass production of lithium-ion cells involves applying a range of manufacturing processes to a range of materials. These processes inevitably result in residual stresses within the individual materials, which when abetted by operational stresses can cause deformation and fracture of the componentry. This contributes to the degradation of electrochemical properties, device performance, and durability of the cells; leading ultimately to cell failure. This experimental study is concerned with determining the mechanical degradation of componentry within cylindrical cells. Mechanical degradation was evaluated for commercial cells using x-ray tomography, mechanical testing and microscopy. Nanoindentation testing was used to characterise mechanical changes in the foil material in three conditions: before cell manufacture, after cell manufacture and after aging. This work represents a novel ex situ characterisation tool and a new approach to understanding degradation in electrochemical systems. Additionally, we anticipate this work to aide modelling of and controlling degradation within electrochemical systems.

(Digital Presentation) The Effect of Dominant Operational Conditions on Capacity Deterioration of Commercial Li-Ion Cells Under Accelerated Testing

Li-ion batteries (LIBs) have been used in a variety of applications including consumer electronics, electric vehicles, space exploration, the defense sector, etc. As a result, the performance and reliability of the commercial LIBs have become extremely crucial which can be monitored by the deterioration in the charge storage over continuous charge-discharge cycling [1]. However, cycling LIBs at the nominal current rate involves excessive time and resource consumption resulting in a slow battery qualification process. Accelerated testing has been proposed to examine the reliability test and for the efficient qualification process of batteries [2]. It is conducted by increasing the operational (stress factors) conditions of the LIBs that have direct implications on the performance and cycle life of a battery. During accelerated testing, capacity deterioration and increase in impedance are recorded periodically, which serve as indicators of degradation of the batteries [3]. Batteries under consideration for the degradation process are closely monitored and the above degradation indicators are recorded at elevated levels of the operational conditions than normal. This process is known as the accelerated degradation test. In literature, there are several operational conditions that have been reported to affect the capacity fade and cycle life of a battery [1-4]. However, the C-rate and ambient temperature are the widely believed dominant factors that have a significant effect on the performance of a battery [2, 4].In this work, we will present a systematic study on the performance degradation of commercial LIBs under accelerated testing using dominant operational conditions viz. C-rate and testing ambient temperature. Capacity fading of commercial cylindrical 18650-type LIBs is monitored at 1 and 2 C-rate while maintaining the ambient temperature during testing at 25 and 35 ℃ in a thermal chamber. Capacity degradation is highly sensitive to C-rate and causes faster fading at higher current rates due to mechanical degradation of electrodes, formation of SEI layer and side reactions. Discharging at high C-rates also causes ohmic heating in the cells increasing their internal temperature which further influences the chemical reaction kinetics [4]. The ambient temperature also has a strong influence on the capacity loss due to the degeneration of the positive electrode and SEI layer formation at the negative electrode [1, 4]. Accelerated testing including the synergistic effect of the ambient temperature and C-rate on the capacity fading and performance evaluation of the commercial LIBs till the end of life or 20% capacity reduction would be presented. Post cycling analysis of the Li-ion cells, in particular, electrode materials and periodic impedance measurements would enable a better understanding of battery failure under such accelerated testing. We believe that the results of this study would pave the way to shorten the duration in the detection of a battery failure and enable an efficient battery qualification process.

Risk Managing Technique in Pakistan Industry: A Case from Pakistan

This study examines the risk management solutions used in the banking sector to meet the many risks. The report also evaluates how conventional and Islamic banks in Pakistan manage risk. This study used primary sources. First, senior managers, risk managers, and chief risk officers from Islamic and normal banks fill out a questionnaire. 51 financial institutions responded. Data analysis uses descriptive statistics, cross-tabulations, t-tests, an ANOVA, and the LSD test. Regular banks' operational risk management strategies and stress test results differ from Islamic banks statistically. The study found no statistically significant difference between Islamic and conventional banks in how well they used risk management tools and systems, how much market risk VaR they used, how much credit risk exposure they had, how they reduced that risk, and how they analyzed their credit risk portfolios.

Research on aging-related degradation of control rod drive system based on dynamic object-oriented Bayesian network and hidden Markov model

The control rod drive system is critical to the reactor's reliable operation. The performance of its control system and mechanical system will gradually deteriorate because of operational and environmental stresses, thus increasing the reactor's operational risk. Currently there are few researches on the aging-related degradation of the entire control rod drive system. Because it is difficult to quantify the effect of various environmental stresses and establish an accurate physical model when multiple mechanisms superimposed in the degradation process. Therefore, this paper investigates the aging-related degradation of a control rod drive system by integrating Dynamic Object-Oriented Bayesian Network and Hidden Markov Model. Uncertainties in the degradation of the control system and mechanical system are addressed by using fuzzy theory and the Hidden Markov Model respectively. A system which consists of eight control rod drive mechanisms divided into two groups is used to demonstrate the method. The aging-related degradation of the control rod drive system is analyzed by the Bayesian inference algorithm based on the accelerated life test data, and the impact of different operating schemes on the system performance is also investigated. Meanwhile, the components or units that have major impact on the system's performance are identified at different operational phases. Finally, several essential safety measures are suggested to mitigate the risk caused by the system degradation.