93 research outputs found

    Firefighters\u27 physical activity across multiple shifts of planned burn work

    Full text link
    Little is currently known about the physical activity patterns of workers in physically demanding populations. The aims of this study were to (a) quantify firefighters\u27 physical activity and sedentary time within (2-h periods) and across planned burn shifts; and (b) examine whether firefighters\u27 activity levels during one shift or 2-h period was associated with their activity levels in the following shift or 2-h period. Thirty-four salaried firefighters (26 men, 8 women) wore an Actical accelerometer for 28 consecutive days. Time spent sedentary (SED) and in light- (LPA), moderate- (MPA) and vigorous-intensity physical activity (VPA) were derived using validated cut-points. Multilevel analyses (shift, participant) were conducted using generalised linear latent and mixed models. Firefighters spent the majority of a planned burn shift (average length 10.4 h) or 2-h period engaged in LPA (69% and 70%, respectively). No significant associations were observed between SED and physical activity levels between consecutive planned burned shifts or 2-h periods. The physical activity that a firefighter engaged in during one shift (or 2-h period) did not subsequently affect their physical activity levels in the subsequent shift (or 2-h period). Further research is needed to establish how workers in physically demanding populations are able to sustain their activity levels over long periods of time

    Exercising Caution Upon Waking–Can Exercise Reduce Sleep Inertia?

    Get PDF
    Sleep inertia, the transitional state of reduced alertness and impaired cognitive performance upon waking, is a safety risk for on-call personnel who can be required to perform critical tasks soon after waking. Sleep inertia countermeasures have previously been investigated; however, none have successfully dissipated sleep inertia within the first 15 min following waking. During this time, on-call personnel could already be driving, providing advice, or performing other safety-critical tasks. Exercise has not yet been investigated as a sleep inertia countermeasure but has the potential to stimulate the key physiological mechanisms that occur upon waking, including changes in cerebral blood flow, the cortisol awakening response, and increases in core body temperature. Here, we examine these physiological processes and hypothesize how exercise can stimulate them, positioning exercise as an effective sleep inertia countermeasure. We then propose key considerations for research investigating the efficacy of exercise as a sleep inertia countermeasure, including the need to determine the intensity and duration of exercise required to reduce sleep inertia, as well as testing the effectiveness of exercise across a range of conditions in which the severity of sleep inertia may vary. Finally, practical considerations are identified, including the recommendation that qualitative field-based research be conducted with on-call personnel to determine the potential constraints in utilizing exercise as a sleep inertia countermeasure in real-world scenarios

    Exercising Caution Upon Waking–Can Exercise Reduce Sleep Inertia?

    Get PDF
    Sleep inertia, the transitional state of reduced alertness and impaired cognitive performance upon waking, is a safety risk for on-call personnel who can be required to perform critical tasks soon after waking. Sleep inertia countermeasures have previously been investigated; however, none have successfully dissipated sleep inertia within the first 15 min following waking. During this time, on-call personnel could already be driving, providing advice, or performing other safety-critical tasks. Exercise has not yet been investigated as a sleep inertia countermeasure but has the potential to stimulate the key physiological mechanisms that occur upon waking, including changes in cerebral blood flow, the cortisol awakening response, and increases in core body temperature. Here, we examine these physiological processes and hypothesize how exercise can stimulate them, positioning exercise as an effective sleep inertia countermeasure. We then propose key considerations for research investigating the efficacy of exercise as a sleep inertia countermeasure, including the need to determine the intensity and duration of exercise required to reduce sleep inertia, as well as testing the effectiveness of exercise across a range of conditions in which the severity of sleep inertia may vary. Finally, practical considerations are identified, including the recommendation that qualitative field-based research be conducted with on-call personnel to determine the potential constraints in utilizing exercise as a sleep inertia countermeasure in real-world scenarios

    Environment-Smart Agriculture and Mapping of Interactions among Environmental Factors at the Farm Level: A Directed Graph Approach

    Get PDF
    Environment-smart agriculture (ESA) aims at sustaining increased agricultural production while limiting negative impacts on the environment. The present study develops an index of composite on-farm environmental impacts (COEI) as a proxy measure to evaluate ESA and validates the index by mapping interactions amongst agriculture related environmental impacts and potential constraints to practice ESA by using the directed graph approach. The cost of mitigation to practice ESA was calculated by estimating the cost of reducing on-farm environmental impacts by using the damage–cost method. The approach was empirically applied to a sample of 317 High Yielding Variety (HYV) rice farms from three intensive rice-growing regions of northwestern Bangladesh. Results showed that the use of chemical pesticides contributed towards higher level of uncertainty in practicing ESA than the use of chemical fertilizers, irrigation and household pollution. The combined effect of the influence from these factor interactions was estimated at 2.3, which falls in the critical region of influence and implies extreme level of uncertainty in practicing ESA. The cost of mitigating negative environmental impacts is higher for the problems of ‘decline in soil fertility’, ‘increases in crop diseases’ and ‘reduction in fish catch’ as compared to other soil and water related impacts. Policy implications include investments in addressing the problems of ‘soil fertility decline’, ‘increases in crop diseases’ and ‘reduction in fish catch’ and raising farmers’ awareness on using farm chemicals to promote ESA practices for HYV rice production

    The impact of sleep restriction and simulated physical firefighting work on acute inflammatory stress responses

    Get PDF
    OBJECTIVES: This study investigated the effect restricted sleep has on wildland firefighters\u27 acute cytokine levels during 3 days and 2 nights of simulated physical wildfire suppression work. METHODS: Firefighters completed multiple days of physical firefighting work separated by either an 8-h (Control condition; n = 18) or 4-h (Sleep restriction condition; n = 17) sleep opportunity each night. Blood samples were collected 4 times a day (i.e., 06:15, 11:30, 18:15, 21:30) from which plasma cytokine levels (IL-6, IL-8, IL-1β, TNF-α, IL-4, IL-10) were measured. RESULTS: The primary findings for cytokine levels revealed a fixed effect for condition that showed higher IL-8 levels among firefighters who received an 8-h sleep each night. An interaction effect demonstrated differing increases in IL-6 over successive days of work for the SR and CON conditions. Fixed effects for time indicated that IL-6 and IL-4 levels increased, while IL-1β, TNF-α and IL-8 levels decreased. There were no significant effects for IL-10 observed. CONCLUSION: Findings demonstrate increased IL-8 levels among firefighters who received an 8-h sleep when compared to those who had a restricted 4-h sleep. Firefighters\u27 IL-6 levels increased in both conditions which may indicate that a 4-h sleep restriction duration and/or period (i.e., 2 nights) was not a significant enough stressor to affect this cytokine. Considering the immunomodulatory properties of IL-6 and IL-4 that inhibit pro-inflammatory cytokines, the rise in IL-6 and IL-4, independent of increases in IL-1β and TNF-α, could indicate a non-damaging response to the stress of simulated physical firefighting work. However, given the link between chronically elevated cytokine levels and several diseases, further research is needed to determine if firefighters\u27 IL-8 and IL-6 levels are elevated following repeated firefighting deployments across a fire season and over multiple fire seasons

    Rethinking International Investment Governance: Principles for the 21st Century

    Get PDF
    Rethinking International Investment Governance: Principles for the 21st Century – written over the course of a week by a distinguished group of experts in international economic governance using the Booksprint process – aims to serve as a practical resource for those interested in the elements of an international investment system that promotes sustainable development and achieves legitimacy by providing benefits to all stakeholders. The objective of Rethinking International Investment Governance is to change the terms of the debate so that societal values and goals are at the center of discussions about each reform proposal and process. This book rethinks international investment law as a key system in global economic governance that should incorporate principles of transparency, participation, reciprocity, accountability, and subsidiarity. It critically evaluates the current system of investment governance in light of those principles and goals. And finally, it proposes possible reforms – including multilateral ones – that would realign the governance of international investment with 21st century goals including reduction of poverty and inequality, and protection of human dignity, the environment and the planet.https://scholarship.law.columbia.edu/sustainable_investment_books/1000/thumbnail.jp

    Sleep in wildland firefighters: what do we know and why does it matter?

    Full text link
    Wildland firefighters perform physical work while being subjected to multiple stressors and adverse, volatile working environments for extended periods. Recent research has highlighted sleep as a significant and potentially modifiable factor impacting operational performance. The aim of this review was to (1) examine the existing literature on firefighters’ sleep quantity and quality during wildland firefighting operations; (2) synthesise the operational and environmental factors that impact on sleep during wildland firefighting; and (3) assess how sleep impacts aspects of firefighters’ health and safety, including mental and physical health, physical task performance, physical activity and cognitive performance. Firefighters’ sleep is restricted during wildfire deployments, particularly when shifts have early start times, are of long duration and when sleeping in temporary accommodation. Shortened sleep impairs cognitive but not physical performance under simulated wildfire conditions. The longer-term impacts of sleep restriction on physiological and mental health require further research. Work shifts should be structured, wherever possible, to provide regular and sufficient recovery opportunities (rest during and sleep between shifts), especially in dangerous working environments where fatigue-related errors have severe consequences. Fire agencies should implement strategies to improve and manage firefighters’ sleep and reduce any adverse impacts on firefighters’ work

    Towards a Cognitive Semantics of Type

    Get PDF
    Types are a crucial concept in conceptual modelling, logic, and knowledge representation as they are an ubiquitous device to un- derstand and formalise the classification of objects. We propose a logical treatment of types based on a cognitively inspired modelling that ac- counts for the amount of information that is actually available to a cer- tain agent in the task of classification. We develop a predicative modal logic whose semantics is based on conceptual spaces that model the ac- tual information that a cognitive agent has about objects, types, and the classification of an object under a certain type. In particular, we ac- count for possible failures in the classification, for the lack of sufficient information, and for some aspects related to vagueness

    The Future of International Investment Regulation: Towards a World Investment Organisation?

    Get PDF
    With growth in foreign investment and in the number of companies investing in foreign countries, the application of general principles of public international law has not been deemed adequate to regulate foreign investment and there is, as yet, no comprehensive international treaty on the regulation of foreign investment. Consequently, states have resorted to bilateral investment treaties (BITs), regional trade and international investment agreements (IIAs) and free trade agreements (FTAs) to supplement and complement the regime of protection for foreign investors. In the absence of an international investment court, states hosting foreign investment or investor states have opted for investor-state dispute settlement mechanism (ISDS). This mechanism has brought about its own challenges to the international law of foreign investment due to inconsistency in the application and interpretation of the key principles of international investment law by such arbitration tribunals, and further, there is no appellate mechanism to bring about some cohesion and consistency in jurisprudence. Therefore, there are various proposals mooted by scholars to address these challenges and they range from tweaks to BITs and IIAs, the creation of an appellate mechanism and the negotiation of a multilateral treaty to proposals for reform of ISDS only. After assessing the merits and demerits of such proposals, this study goes further, arguing for the creation of a World Investment Organisation (WIO) with a standing mechanism for settlement of investment disputes in order to ensure legal certainty, predictability and the promotion of the flow of foreign investment in a sustainable and responsible manner
    • …
    corecore