bluuebunny/crossref_metadata_2025 huggingface dataset:
Snow Cover Variability in the Beas River Basin and its relation with climate parameters during 2007-2018
Authors: Sunita  , Gupta Pardeep Kumar , Gusain Hemendra Singh , Gill Anhad Singh , Sidhu Onkar Singh
Published: June 2024

In the Himalayan zone, snow is a crucial component of cryosphere for efficient use of water resource management. The major objective of this research paper is to analyse snow dynamics in the Beas River basin using MODIS satellite images from 2007-2018, thus revealing important insights into the region’s snow cover variability and its potential impacts on the hydrological cycle. In this paper, the snow cover area (SCA) analysis has been done for the Beas River basin from 2007-2018 using the 8-day improved snow cover product (version 6) Terra-aqua (MOYDGL06*) MODIS sensor images and ERA5 data for winter period i.e., November to April. During the time period, SCA in the region ranged from ~46% (Nov 2016) to ~92% (Feb 2015). SCA and total precipitation were found to be declining at rates of 2.5 km2 and 52.2 cm, respectively. While the average temperature has been rising from 2007 to 2013 at a pace of 0.14°C. Though, SCA decreased at a faster rate of 20.49 km2 and total precipitation decreased at a faster rate of 36.2 cm during 2013-2018. In contrast, the mean temperature increased at a higher rate (0.38 °C). The study finds that SCA and precipitation are falling at a faster rate during 2013-2018. The trend derived from satellite data analysis of SCA was found to be consistent with the climate parameters. The study suggests that climate change is likely a major factor contributing to the observed trends in SCA, total precipitation, and mean temperature. The study also notes that the observed SCA trend is consistent with climate parameters. The paper investigates the fluctuations in SCA from November to April.
Waste materials as concrete aggregate - A systematic review
Authors: Banerjee Debargha , Nanda Radhikesh Prasad
Published: June 2024

Over the last few years, the rate at which metropolitan areas and industries have expanded worldwide has increased, leading to a significant increase in the usage of concrete and the depletion of natural resources like aggregate. This essay aims to thoroughly analyze the use of different wastes as aggregate in cement concrete. Critical reviews have been conducted on the consequences of using such waste materials on the mechanical characteristics of concrete products. From the results of many experiments, it may be inferred that waste can be used in cement concrete instead of natural aggregate. A thorough overview in tabular form is provided for quick access for the benefit of researchers. Further, the outcome of this investigation is expected to accelerate waste utilization for sustainable construction.
Microstructure and performance of carbon fiber reinforced aluminum matrix composites with molybdenum carbide coating on carbon fibers
Authors: Liu Tingting , He Xinbo , Zhang Lin , Ren Shubin , Qu Xuanhui
Published: June 2024

In this work, a molybdenum carbide coating on the surface of short carbon fibers prepared using molten salt method was proposed to ameliorate the interfacial bonding and improve the performance of carbon fiber/Al composites. The carbon fiber/Al composites were produced using vacuum hot pressing. The characteristics of molybdenum carbide coating were analyzed. Besides, the microstructures, bending strength and thermal properties of the carbon fiber/Al composites were explored. Furthermore, the interfacial thermal resistance of the composites was investigated in relation to theoretical evaluations derived from the combined Maxwell-Garnett effective medium approach and acoustic mismatch model schemes. The results indicated that a homogeneous Mo2C coating with a thickness of 0.5 μm was obtained by proper molar ratio of carbon fibers, MoO3 and chloride salts mixture and heated at 1000 °C for 60 min. The Mo2C coating greatly enhanced the bond between the aluminum matrix and carbon fiber, leading to improvements in the densification behavior and bending strength of the coated composites. The enhanced thermal properties including improved thermal conductivity and reduced coefficient of thermal expansion (CTE) were also achieved by the Mo2C coating. The in-plane thermal conductivity of 60 vol.% Mo2C-coated carbon fiber/Al composite was 221 W·m−1·K−1 enhanced by 92% compared to that of uncoated composite and the CTE was 6.0 × 10–6 K−1 which was suitable for electronic packaging materials.
Enhancing microstructural and mechanical properties of magnesium AZ31 matrix composites through friction stir processing incorporating silicon carbide, titanium carbide, and graphite particles
Authors: K P Boopathiraja , Ramamoorthi R , Hariprasad P , Arockiasamy Felix Sahayaraj
Published: June 2024

The present study focuses on investigating the effect of reinforcement on the microstructure and mechanical properties of friction-stir-processed magnesium hybrid composites. The groove width (0, 0.7, 1.1, 1.7, and 2.3 mm) of the Magnesium AZ31 plates was varied by varying the volume fractions (0, 5, 10, 15, and 20 vol%) of Silicon Carbide (SiC), Titanium Carbide (TiC), and Graphite (Gr) particle reinforcements in the hybrid composite. Single-pass processing was suspended using a cylindrical tool shoulder with a rotational speed, transverse velocity, and axial pressure of 1000 rpm, 30 mm min−1, and 6 kN, respectively. The optical micrograph clearly shows that a non-cluster zone (reinforcement particles are uniformly distributed without agglomeration) was identified in the processed region of the least concentrated composites. The results revealed that a peak tensile strength of 293.546 ± 5.12 MPa was attained for the combination of 10 vol% composites, and a Vickers hardness number of 86.53 HV was achieved for the 20 vol.% composites. The fracture surface morphology was analyzed using a Scanning Electron Microscope (SEM). The mode of tensile fractography was ductile for the least composite and transformed into a brittle mode of failure with the addition of reinforcements.
Flexible self-powered triboelectric nanogenerator sensor for wind speed measurement driven by moving trains
Authors: Dong Wentao , Huang Bo , Sheng Kaiqi , Cheng Xiao
Published: June 2024

Flexible self-powered sensors have been extensively applied to the Internet of Things, structural health monitoring (SHM), and intelligent transportation. It would be more demanding for the power supply to these sensors during the long-term maintenance of the rail transit system. The wind pressure/velocity generated by high-speed trains poses a substantial threat to safety of human, and new sensors without an external power supply should be developed to monitor wind pressure/velocity in the trackside. Flexible self-powered wind triboelectric nanogenerator (W-TENG) sensor with a single-electrode mode based on conductive hydrogel is designed to wind pressure/velocity monitoring without power supply by harvesting wind energy. It is devoted the relationship between the output voltage of the sensors and the wind pressure/velocity driven by high-speed trains. Material selection and structural design methods are adopted to enhance the energy harvesting efficiency and sensing accuracy of self-powered W-TENG sensors. Open-circuit current of 2.8 μA and open-circuit voltage of 12 V are achieved, and the output voltage signal has the linear relationship with trackside wind pressure/velocity. Field tests are implemented to evaluate the performance of self-powered W-TENG sensors in wind pressure/velocity measurement caused by moving trains, providing an idea to SHM application in intelligent transmit systems.
Examining the confluence of climate change and conflicts on agricultural and livestock exports in Somalia
Authors: Abdi Abdikafi Hassan , Mohamed Abdisalan Aden , Sugow Mohamed Okash , Halane Dhaqane Roble
Published: June 2024

Climate-induced extreme weather events and conflicts are jointly contributing to disruptions in agricultural supply chains and destabilizing global food trade. Since the literature has identified that variations in climatic conditions hamper farming and animal raising, it is necessary to explore the consequences of climate change on crop and livestock exports in order to implement policies that mitigate the exposure and enhance exports. In this context, this study aims to examine the confluence of climate change and conflicts—internal and external—on agricultural and livestock exports in Somalia during 1985–2017. The evidence from the cointegration analysis verified the presence of a consistent long-run cointegration between the variables. The empirical results of the ARDL approach indicate that average rainfall enhances agricultural and livestock exports in Somalia in the short-run and long-run, while mean temperature particularly hampers agricultural exports in the long-run. Despite livestock production was found to be statistically insignificant, crop production positively contributes to agricultural exports. In addition, increases in rural population enhance both export categories in the short-run and long-run. A striking finding from the study indicates that internal and external conflicts decrease crop and animal exports in the long-run, although the coefficients of external conflicts were statistically insignificant. The long-run findings were validated using the FMOLS cointegration approach. Moreover, the causality findings demonstrate a unidirectional causality from agricultural exports to precipitation, temperature fluctuations, and internal conflicts. Furthermore, the study shows that agricultural labor Granger causes farm and livestock exports. To this end, this study recommends policymakers promote product diversification, foster sustainable land management practices, facilitate market access, and invest in resilient farming systems.
Learning fast while changing slow in spiking neural networks
Authors: Capone Cristiano , Muratore Paolo
Published: June 2024

Reinforcement learning (RL) faces substantial challenges when applied to real-life problems, primarily stemming from the scarcity of available data due to limited interactions with the environment. This limitation is exacerbated by the fact that RL often demands a considerable volume of data for effective learning. The complexity escalates further when implementing RL in recurrent spiking networks, where inherent noise introduced by spikes adds a layer of difficulty. Life-long learning machines must inherently resolve the plasticity-stability paradox. Striking a balance between acquiring new knowledge and maintaining stability is crucial for artificial agents. To address this challenge, we draw inspiration from machine learning technology and introduce a biologically plausible implementation of proximal policy optimization, referred to as lf-cs (learning fast changing slow). Our approach results in two notable advancements: firstly, the capacity to assimilate new information into a new policy without requiring alterations to the current policy; and secondly, the capability to replay experiences without experiencing policy divergence. Furthermore, when contrasted with other experience replay techniques, our method demonstrates the added advantage of being computationally efficient in an online setting. We demonstrate that the proposed methodology enhances the efficiency of learning, showcasing its potential impact on neuromorphic and real-world applications.
Efficient sparse spiking auto-encoder for reconstruction, denoising and classification
Authors: Walters Ben , Rahimian Kalatehbali Hamid , Cai Zhengyu , Genov Roman , Amirsoleimani Amirali , Eshraghian Jason , Rahimi Azghadi Mostafa
Published: June 2024

Auto-encoders are capable of performing input reconstruction, denoising, and classification through an encoder-decoder structure. Spiking Auto-Encoders (SAEs) can utilize asynchronous sparse spikes to improve power efficiency and processing latency on neuromorphic hardware. In our work, we propose an efficient SAE trained using only Spike-Timing-Dependant Plasticity (STDP) learning. Our auto-encoder uses the Time-To-First-Spike (TTFS) encoding scheme and needs to update all synaptic weights only once per input, promoting both training and inference efficiency due to the extreme sparsity. We showcase robust reconstruction performance on the Modified National Institute of Standards and Technology (MNIST) and Fashion-MNIST datasets with significantly fewer spikes compared to state-of-the-art SAEs by 1–3 orders of magnitude. Moreover, we achieve robust noise reduction results on the MNIST dataset. When the same noisy inputs are used for classification, accuracy degradation is reduced by 30%–80% compared to prior works. It also exhibits classification accuracies comparable to previous STDP-based classifiers, while remaining competitive with other backpropagation-based spiking classifiers that require global learning through gradients and significantly more spikes for encoding and classification of MNIST/Fashion-MNIST inputs. The presented results demonstrate a promising pathway towards building efficient sparse spiking auto-encoders with local learning, making them highly suited for hardware integration.
Epistemology
Authors: Mueller Sean
Published: June 2024

This chapter discusses how shared rule as regional government influence over national decisions can be measured empirically. It builds on the Regional Authority Index, which assesses the formal dimensions of said influence but adds a more comprehensive typology that includes informality too. Based on a survey among thirty-eight federalism scholars on eleven different federal political systems, five distinct methods of influence-seeking are identified and their prominence quantified across those countries. Those five channels are using the media and public relations to build up pressure; professional territorial lobbying financed and directed by regional governments; political parties; direct personal contacts in inter-governmental meetings; and intra-institutional influence through bodies such as the German Bundesrat. Direct democracy and judicial litigation are important instruments used within those channels which, although in principle distinct, are in practice often combined.
Feminist Bioethics in Space
Authors: Szocik Konrad
Published: June 2024

This book is an example of applying the feminist perspective in philosophy, ethics, and bioethics to the consideration of future human space missions. Feminism is a thought perspective that is rarely present in the reflection on space and space missions. This book focuses on bioethical issues that may arise in future long-term and long-distance space missions. The issues are primarily human enhancement and human reproduction in space. Applying the perspective of feminist bioethics makes it possible to see potential risks that are not usually raised by nonfeminist bioethics. The book points out the consequences of space missions for traditionally marginalized and excluded groups, such as women, nonwhites, people with disabilities, indigenous people, and the sexually nonbinary. In a manner appropriate to feminism, the book discusses ethical and bioethical issues using such explanatory categories as sex and gender, power, oppression, discrimination, domination, and exclusion. The book offers a broad perspective, going beyond bioethical issues to a wider context that includes the global situation in the world. The book offers an intersectional perspective, highlighting the dangers and risks of overlapping different types of oppression and discrimination. While most attention is given to the situation of women and their potential oppression in space, particularly in the context of their reproductive rights, considerable attention is given to other excluded groups, including the disabled. The book aims to sensitize us to the need to recognize in our activities the risks of inequality and exclusion that may be replicated in space.
An Introduction to Feminist Ethics and Bioethics
Authors: Szocik Konrad
Published: June 2024

This chapter is an introduction to feminist ethics and bioethics, not necessarily related to the issue of space exploration. Key categories and concepts specific to feminism are discussed, such as the culturally and socially inferior position of women in a sexist and patriarchal society, gender issues, ethics of care versus power-based ethics, as well as feminist critiques of dominant, nonfeminist philosophy and ethics. The chapter draws attention to the multiplicity of positions in feminist ethics and bioethics. This multiplicity, however, accounts for the richness of feminism, which points to the complexity of each situation. This diversity within feminist thought seems particularly useful when considering the future challenges of humanity, including our presence in space.
An Introduction to Feminist Bioethics in Space
Authors: Szocik Konrad
Published: June 2024

This chapter introduces the concept of feminist bioethics of space exploration into the world literature for the first time. Selected bioethical problems in space such as the problem of autonomy or justice are analyzed. The chapter also discusses the issue of the potential difference between feminist bioethics on Earth and feminist bioethics in space. The difference between feminist bioethics and feminist ethics of space exploration is also discussed, and a number of methodological issues inherent in feminist bioethics of space exploration are analyzed. The chapter also shows the place of feminism and feminist bioethics in the philosophy of space exploration. It also presents a feminist critique of the methodology of non-feminist bioethics.
Disability in Space
Authors: Szocik Konrad
Published: June 2024

This chapter discusses the issue of disability in space. A feminist approach to disability in general is presented. The problematic nature of viewing disability in the cosmos from the perspective of the masculinist ideal of able-bodiedness is discussed, which is not due to the specifics of disability itself, but to the way it is understood through the lens of the able-bodied norm. The chapter also examines whether excluding people with disabilities from participating in space missions can be morally justified in at least some cases. The issue of negative and positive selection in a future base in space, where reproduction would be possible, is also discussed.
Feminist Bioethics of Human Enhancement
Authors: Szocik Konrad
Published: June 2024

This chapter discusses the most important issue for feminist bioethics of space missions, namely the issue of human enhancement and reproduction in space. The problematic nature of the notion of the norm, which has exclusionary potential, is presented. The chapter shows how the idea of human enhancement can negatively affect women in particular. Commodification, medicalization, and instrumental treatment of the female body, which is subject to constant scrutiny and monitoring, is discussed. These phenomena will increase rather than decrease in the cosmos. Feminist arguments for and against germ cell modification are discussed. Finally, considerable attention is given to the feminist approach to reproduction, and potential threats to reproductive rights in space are shown.
Antinatalism, Environmental Ethics, and Feminism
Authors: Szocik Konrad
Published: June 2024

This chapter examines issues of antinatalism in the context of global challenges on Earth such as climate change and “overpopulation.” The chapter discusses topics inherent in population ethics and looks at the controversial idea of population reduction, pointing out its contentious dimensions. A critique of these ideals specific to feminist bioethics is presented, as well as a critique of antinatalism, clearly distinguishing discriminatory political antinatalism from philosophical antinatalism. Philosophical issues related to the notion of a life worth living, as well as concern for future people, are discussed. The chapter also draws attention to ecofeminism in both the earthly context and regarding our expansion into space.
Conclusions
Authors: Szocik Konrad
Published: June 2024

It is highly likely that expansion into space will be an important part of humanity’s future. In itself, it is probably something to be viewed positively. The feminist perspective adopted in this book, however, suggests skepticism and caution in analyzing the potential long-term consequences of our presence in space. Feminism pays particular attention to the risks of exclusion and oppression. Feminist bioethics analyzes selected biomedical issues in space in a way that differs from nonfeminist bioethics. The task of skepticism inherent in the feminist perspective is to seek to avoid worst-case scenarios. The main premise of the feminist approach to reflecting on our future in the space is that our knowledge of the mechanisms of discrimination, exploitation, and oppression should set the framework for thinking about the future and can never be ignored.
The Enlightenment
Authors: Clark J C D
Published: June 2024

Many books claim to explain the Enlightenment, but they all assume that it was a thing. This is the first book to show what it actually was, namely an historiographical concept. It is a critical historical analysis of the Enlightenment in England, Scotland, France, Germany, and the United States, from c.1650 to the present. It argues that the degree of commonality between social and intellectual movements in each, and between the five societies, has been overstated for polemical purposes, some of which it explores. It contends that the concept of ‘the Enlightenment’ was not widely adopted in those societies until the mid twentieth century; indeed it was unknown in the eighteenth. Without the concept, people at the time were unable to act in ways that would have created the Enlightenment as a movement. Since the conventional account has been that the Enlightenment was a phenomenon, the idea could be used as a component of what has been called a ‘civil religion’, a summing up of the myths of origin, aims, and essential values of a society from which dissent is not permitted. An appreciation that it was instead an historiographical concept in turn undermines the idea that there was, in these societies, a great transition to what came to be called ‘modernity’. Currently ‘the Enlightenment’ is a term widely accepted across popular culture and in many academic disciplines, notably history, philosophy, political theory, political science, literary studies, and theology; this book calls for fundamental reconsiderations in each.
What Was English Discourse?
Authors: Clark J C D
Published: June 2024

Chapter 3 begins to investigate what eighteenth-century English discourse and its key concepts were, if ‘the Enlightenment’ in its present sense was not part of it. It focuses on four leading concepts, but concepts closely related in the world view retrojected onto the eighteenth century by late modernism: liberalism, philosophy, progress, and enlightenment. The first and fourth it identifies as imports from Spain and Germany respectively, the second and third it contends lacked their present meanings. It offers contextual studies that place these four terms within the meanings ascribed to them in the eighteenth century, and so contributes to reconstruct English-language discourse in its eighteenth-century forms.
Did Liberals Recognize the Enlightenment?
Authors: Clark J C D
Published: June 2024

It has been conventional to see nineteenth-century Britain as dominated by a reified ‘liberalism’, and to see liberalism as an organized, normative, unified campaign that carried forward ideals or a sense of coherence from the eighteenth century. Chapter 8 argues that British liberalism took longer to emerge, that it was very various in its tenets, and that its supposed leading light, John Stuart Mill, was driven in framing his overarching scenario by a need to assert a moral emancipation that had not happened in any earlier age. Into the early twentieth century British liberalism was not built by its advocates on an historical model that linked it with any eighteenth-century antecedents.
How Did Different Nationalities Construct their Enlightenment?
Authors: Clark J C D
Published: June 2024

The Enlightenment is not merely a category for academic historians; it has been adopted, and fought over, in several societies that have developed what has been called by Robert N. Bellah a civil religion. The general patterns of debate are here traced in the United States, France, Germany, and Scotland, societies that were often framed in armed conflict and that continue to be locked in disagreement, often agonized, over the meaning of an episode of founding. Finally, the current state is considered of the debate over whether there was one Enlightenment, or many Enlightenments, or whether this has been a question wrongly framed.
State Capitalism Begets State Capitalism
Authors: Alami Ilias , Dixon Adam D
Published: June 2024

The chapter emphasizes the role of combination and political multiplicity as a particularly potent dynamic in contemporary state capitalism. Its overall contention is that relational co-constitution shapes the form and outcome of emerging state capitalist landscapes. The various repertoires of state intervention develop in dynamic, inter-referential, and combinatorial forms, resulting in cumulative effects, which themselves produce further extensions of state prerogatives. Indeed, a particular form of state activism may have cascading impacts and ricocheting effects across geographic space, including in non-adjacent locations and faraway places, insofar as they spark a policy response on the part of states which are directly affected. Effects may be less direct (but no less significant) when a particular modality of state intervention in one place transforms economic conditions and sociopolitical relations elsewhere, in turn prompting other states to react to this new context by developing novel prerogatives. The picture that emerges, then, is less one of a mosaic of neatly demarcated varieties of capitalism, than one of moving landscapes of state intervention that are created and transformed over time through interconnected socio-spatial processes and interactions. The chapter substantiates this claim by tracing three types of combinatorial mechanisms: (1) competitive emulation in the context of geoeconomic and geopolitical rivalry; (2) peer group learning and mimetic behaviour; (3) enabling and mutual reinforcement. These various cases illustrate that state capitalism tends to develop in a spiral-like movement, with self-reinforcing state transformations expanding geographically and across policy domains. The chapter calls this the ‘spiral of state capitalism’.
Military Strategy: A Very Short Introduction
Authors: Echevarria II Antulio J.
Published: June 2024

Military strategy plays a vital role in every conflict. Inspired by the great military theoreticians Sun Tzu, Niccolò Machiavelli, and Carl von Clausewitz, Military Strategy: A Very Short Introduction highlights the dynamic relationship among the principal components of strategy: purpose, method, and means. It draws on examples such as Hannibal’s war against Rome, Napoleon’s victory at Austerlitz, the Allies’ campaign to overwhelm Hitler’s Fortress Europe, and the terror attacks of September 11, 2001, to illustrate the factors contributing to the success or failure of military strategy. The major types of military strategy and their advantages and disadvantages are described: annihilation and dislocation, attrition and exhaustion, deterrence and coercion, terror and terrorism, targeted killing, and cyber power.
Terror and terrorism
Authors: Echevarria II Antulio J.
Published: June 2024

“Terror and terrorism” discusses strategies in which terror is used to break an opponent’s willingness to fight or to induce a change in a rival power’s policy or behavior. Terror often causes little damage to a foe’s physical capacity to fight, even if it inflicts mass casualties. Targets are usually chosen for their psychological rather than their material effect. Terror and terrorism are military strategies largely because of their coercive power. Terrorism is violence (discriminate or otherwise) directed against noncombatants to influence public opinion or to modify a government’s policies. Whether terrorism constitutes a strategy or a tactic is still a matter of debate.
Pandemics: A Very Short Introduction
Authors: McMillen Christian W.
Published: June 2024

The 2014 Ebola epidemic demonstrated the power of pandemics and their ability not only to destroy lives locally but also to capture imaginations worldwide. Pandemics: A Very Short Introduction provides a concise yet comprehensive account of pandemics throughout human history, illustrating the ways in which pandemic disease—including plague, tuberculosis, malaria, smallpox, cholera, influenza, HIV/AIDS, and Covid 19—has shaped history and how human history has shaped pandemic disease. By considering the explosion of medical research and the varying state responses, such as quarantine and travel restrictions, this Very Short Introduction shows why pandemics are both interesting from a medical standpoint and provide insight into the culture and politics of their time.
347 Did occupational hygienists make a difference for workers during the pandemic?
Authors: Brosseau Lisa
Published: June 2024

Occupational hygienists are uniquely prepared to recognize, evaluate and control novel workplace hazards, but the profession was often sidelined and marginalized in the development and deployment of workplace guidance during the COVID-19 pandemic. Workplaces were among the most hazardous settings for COVID-19 transmission, but the interventions we employ for workplace hazards were often ignored. Beyond the pandemic, infectious respiratory diseases are an important factor in worker health and safety and deserve our ongoing attention.

Workers can be both the source and receptor of an infectious aerosol, which complicates our approach to the hierarchy of controls. However, the underlying principles remain the same. Whether used as source control or personal protection, masks and respirators are the final option, because they rely on humans for effective deployment. As well, mandating vaccines for workers must be carefully considered, in light of their limitations and placement in the hierarchy. This calls for a reconsideration and reframing of the control hierarchy.

Exposure to a hazardous aerosol, whether generated by people or industrial processes, requires consideration of particle concentration and exposure time. Control banding, which has been successfully applied when hazards lack exposure limits, should become an accepted tool for assessing infectious aerosol exposures.

Occupational health is a public health discipline but is often ignored and sidelined by medical and public health professionals. We lack health and safety standards and regulations focused on recognition, evaluation and prevention of infectious disease transmission in workplaces. Occupational hygienists could play a more active role in the development of such guidelines and standards. We can’t let an incomplete understanding of the exposure or the lack of sampling methods or exposure limits prevent our taking a leadership role in protecting workers from aerosol transmissible diseases.
42 Interventions to reduce PAH exposure in wildland firefighters
Authors: Broznitsky Natasha , Durrad Tristan , Kinniburgh David , Kimble Levi , Litchy Andrew , Shum Mona , Tiu Sylvia , Zadunayski Tanis , Cherry Nicola
Published: June 2024

Wildland firefighters are repeatedly exposed to smoke and particles during increasingly long and fierce wildfire seasons with both inhalation and skin absorption of polycyclic aromatic hydrocarbons (PAHs). Wildfire firefighters do not habitually use respiratory protection and good skin hygiene to reduce exposure through contaminated clothing and equipment can be difficult for those living in camp. We introduced interventions to reduce exposures during the 2019, 2021 and 2023 fire seasons, with urinary 1-hydroxypyrene (1-HP), as the outcome marker for PAH absorption. Secondary outcomes included self-reports of mask wearing and post fire respiratory symptom. Sources of PAH exposure were evaluated by personal sampling pumps and skin wipes.

A total of 281 firefighters from the western Canadian provinces of Alberta and British Columbia took part over the three fire seasons. Interventions in 2019 and 2021 addressed both skin hygiene and mask wearing: the 2023 intervention compares the effects of three types of mask, half-face with P100 cartridges fire mask and mesh mask.

Data collection for the 2023 season has been completed and analysis is in progress, with results expected early in 2023. Data from previous seasons have shown a strong relation between ambient air and skin wipe PAHs and urinary 1-HP, with lower than predicted values in those randomly allocated to wear a mask. A minority of those allocated masks wore them little or not at all, citing discomfort and difficulties carrying out their tasks. The 2023 season data will give clearer indication of the type of mask most efficient and acceptable.
54 Food insecurity as a worsening occupational hazard
Authors: Alban Ashton
Published: June 2024

When asking the question “what topics are most pertinent to worker health and safety?” many respond with topics like heat, training, fall protection, etc. Very few will respond with food insecurity as a topic; however, internationally food security has been on the rise due to factors like conflict and climate change that are exacerbating the issue. This session explores the role that nutrition plays on cognitive and physical function and how the workplace is impacted by worker nutritional status. After establishing the impact that nutrition has on the workplace, the session dives deeper to discern how the rising rates of food insecurity could impact the changing workplace through increases in worker injury. The session will implore individuals and companies to consider how food insecurity is impacting workers and the role of OEHS professionals to address it.
65 What to wear? Occupational hygiene applications for wearables
Authors: Shum Mona , McLean Scott , Lu Elizabeth
Published: June 2024

Evaluation of exposure in occupational hygiene usually means monitoring the environment in which workers work and then comparing those measurements to established exposure limits. This one size-fits-all approach is protective of the majority of a healthy working population but does not account for variability in how individual workers react or metabolize certain hazards. Wearable technologies continue to evolve and proliferate, particularly in the workplace, being used to monitor a broad range of employee performance and health metrics in equally diverse use case environments. These technologies afford continuous monitoring of individual-specific data-driven outcomes, enabling more targeted risk mitigations and interventions to be developed, implemented, and evaluated. Wearable devices that can detect, measure, and compare a user’s heart rate, sweat output and composition, fatigue, sleep quality, etc., for example, would allow occupational hygienists to monitor and remedy, where possible, individual effects of exposure, both acutely and longitudinally, in a way that hanging an environmental monitor on a worker, simply cannot. Moreover, these data can be aggregated and visualized at the employer-level, such that targeted strategies for enhancing employee performance and health can be developed, evaluated, and refined as needed. Additionally, they provide a means through which complementary employee-specific insights and guidance can be provided to enhance compliance. This round table session will discuss the potential for wearables integration for occupational exposure evaluations, overarching research, testing, and evaluation approaches to inform optimal fit-for-purpose solutions, and thus the utility, challenges, and opportunities for using targeted wearables for occupational exposure purposes moving forward.
68 Human Biomonitoring (HBM) for emergency responders - Basic considerations, a practical approach and lessons learned
Authors: Bader Michael , Bäcker Sandra , Jäger Thomas , Webendörfer Stefan , Kaller Martin , Pfrang Jörg , Van Bortel Gert
Published: June 2024

Chemical incidents such as fires of different types and sizes as well as accidental spills and leakages, or the unintended release of hazardous substances into the environment are typical scenarios that require an emergency response. The potential hazard and health risk caused by exposure to chemical substances has been discussed and reviewed repeatedly in recent years. According to an evaluation by the International Agency on Cancer Research (IARC), the work as a firefighter is classified as Group 1 carcinogenic. Therefore, the quantitative analysis and assessment of exposure to hazardous chemicals after incidents has received an increasing interest among firefighters and health and safety authorities in disaster management. Human biomonitoring (HBM), the analysis of hazardous substances or their metabolites in human biological material such as blood and urine, is one meaningful approach for the assessment of individual exposure. The practical application, however, requires a certain degree of preparedness, accessibility of resources, and a transparent decision process. This presentation describes the basics of HBM (selection of parameters, sampling, storage, assessment values), the challenges (sampling time limitations, transport issues, interpretation, report chains) as well as examples of already established emergency HBM systems within the chemical industry and beyond. The lessons learned from several small-scale operations up to major accidents point out to the paramount role of preparedness (sampling material, questionnaires, laboratory network) and the communication of results. In essence, HBM after chemical incidents is a well-established and valuable tool for exposure assessment and risk communication if basic requirements are met.
73 Case study: Using a project-based approach to educate occupational hygiene students in the science of real-time monitoring
Authors: Linde Stefan , du Preez Sonette
Published: June 2024

Introduction

The use of real-time monitoring instruments to assess occupational exposure to workplace stressors is becoming increasingly popular. However, these instruments need to be used correctly to obtain trustworthy results. To accommodate this evolution, educators need to train students on the proper use and application of these instruments in the workplace. This study describes a project-based strategy used to train occupational hygiene students at the North-West University in various aspects of real-time monitoring.

Methodology

During this specific project, a group of three students, under the guidance of a supervisor, performed area monitoring for respirable particulates and noise at a clay brick factory using real-time monitoring instruments. For respirable particulates, the Nanozen DustCount 9000 and the conventional NIOSH 0600 was used, and the Svantek SV 104 dosimeter was used for noise monitoring. The project-based learning activities included 1) coaching and demonstrations from the supervisor, 2) individual practice, 3) collaboration, 4) in-field monitoring, 5) data analysis, 6) report writing, and 7) supervisory quality control.

Results

Thirteen sets of respirable dust and noise measurements were successfully collected, analysed and reported. Data from the real-time monitoring for respirable dust and noise could be linked to activities in the plant, such as the use of compressed air and shutdowns, which students found fascinating. Even though some mistakes made, errors were corrected during supervisory quality control, which helped the students to learn from the mistakes.

Conclusions

The project-based strategy incorporated communication, collaboration, critical thinking, and troubleshooting to guide students in the learning process, increase their confidence and enhance workplace readiness with regards to real-time monitoring.
260 Characterisation of emission and exposure to diesel engine exhaust from trackless mobile machinery in underground South African platinum mines
Authors: Manyike-Modau Amukelani , Brouwer Derk
Published: June 2024

Background

Mining remains one of the major economic drivers in South Africa, and there is a continued focus on long-term investments in mechanisation. The use of diesel-powered machines in mechanised mining has introduced a new risk among the mine workers in underground confined spaces. Evidence has shown a correlation between diesel exhaust engine (DEE) exposure and respiratory outcomes in mine workers. Recent mining research has shifted to focus on integrated control strategies/solutions to prevent exposure to DEE exposure.

Objective

The overarching aim of the research project was to determine characteristics of diesel engine exhaust emission at the source (aerodynamic size fractions) and to evaluate how interventions will impact the levels of DEE at the source and the workplace.

Methods

The study approach was a quantitative quasi-experimental designed study with an intervention component conducted in underground South African mines. DEE was measured at the source on the trackless mobile machinery (TMM) tailpipe, followed by different interventions and personal exposure measurements of diesel particulate matter (DPM) using EC as a surrogate measure for DPM and pollutant dispersion.

Results

The median particle number concentration significantly decreased post the interventions; an efficacy of 90-96% and 20-40% (p-value=0.001) was achieved for the machines that underwent maintenance plus installation of the DPF and machines that underwent maintenance only, respectively. Most particles emitted were between ≥0.01<0.1µm and ≥0.1<1µm.

Conclusion

A combination of control strategies (maintenance, retrofitting of machines with DPF, and ventilation) have shown great potential to reduce DEE in underground mines. Focus on implementing integrated strategies in preventing and reducing exposure to DEE is required.
328 Evaluation of a novel respirator fit testing apparatus (Sibata’s MT-11D): pilot study
Authors: Grinshpun Sergey , Yermakov Michael , Niu Xinyi
Published: June 2024

Performance of a respiratory protective device largely depends on how well this device fits the wearer. Therefore, quantitative fit testing of particulate respirators is very important for achieving the intended protection level. Millions of fit tests are conducted by workers every year using a US OSHA-accepted standard protocol and a PortaCount instrument (TSI Inc, Shoreview, MN, USA) which measures a respirator fit factor. Several alternative fit testing instruments have been recently developed. Among them is an MT-11D (Sibata Scientific Technology Ltd, Tokyo, Japan), The novel instrument, like the PortaCount, utilizes the condensation particle counting principle but it features an advanced saturation chamber and has other design advantages over the PortaCount. In this pilot study, the newly developed apparatus was evaluated against the PortaCount (utilized as the reference instrument) using the standard fit testing protocol. The evaluation was performed with three types of respirators – an N95 filtering facepiece respirator (FFR), P100 FFR, and half-mask elastomeric facepiece, each represented by three different models and manufacturers and donned on 6 subjects. The comparative testing and analysis showed a good correlation between the fit factors measured by the two instruments. It was concluded that the MT-11D is capable of identifying an inadequate fit of the tested respirators with high sensitivity and specificity. The novel fit testing apparatus demonstrated an acceptable performance and thus can be successfully deployed for the quantitative respirator fit testing.
25a - Risk assessment of diesel engine exhaust emissions
Authors: Hills Alex
Published: June 2024

As diesel engine exhaust emissions (DEEES) are a complex mixture of substances there has been little formal agreement on how exposures to them should be assessed. Several different monitoring and analysis methods have been developed, many relying on using a constituent of the exhaust emission as a surrogate or concentrating on either the particulate fraction or gaseous fraction only. In practice this means that results across monitoring surveys cannot be reliably correlated. This work is to propose a standard reference methodology for risk-based health assessments.
148d - Performance metrics towards adoption and operationalization of aerosol sensors
Authors: Cauda Emanuele
Published: June 2024

The adoption and potential operationalization of aerosol sensors in occupational hygiene entails an understanding of the performance of a specific sensor to measure the aerosol of interest. Often, hygienists intend to monitor the airborne mass concentration of a certain aerosol and most sensor technologies can only provide estimates since they do not measure mass directly. Technological advancements in terms of sensors and algorithms will improve the performance of products in the future. But this might come with an increased cost and indirectly hindered adoption in most environments. Practices such as assessment and evaluation of the performance conducted periodically by the manufacturer and field assessment and calibration of the aerosol sensors can increase the confidence in the data generated. The field practices are not well established and hygienists should consider them as an important step of their activities. This contribution will provide an overview of the performance metrics for aerosol sensors that occupational hygienists should consider during the selection and adoption of the technologies. Most metrics can be applied to both personal and area aerosol monitors and for low-cost and medium-cost devices. For each metric, suggestions will be shared on how to measure it in the field and how hygienists can engage with manufacturers to receive information.
208b The role of WHWB in international efforts to eliminate asbestos use and deal with its legacy
Authors: Farquhar Alec , Hodgkiss Jason
Published: June 2024

Globally, asbestos use is down by around 70% from the maximum level reached in the 1970s. However asbestos use remains a significant occupational exposure in a number of countries, particularly in Asia. There is also a tremendous amount of legacy asbestos in the built environment all over the world. So there is still much to do working towards a global ban on the use of asbestos, as well as eliminating legacy asbestos from the built environment.

WHWB has established a global Asbestos Working Group to focus on issues where our occupational health expertise can add the most value. This includes identifying substitutes for asbestos in manufacturing asbestos cement products, especially corrugated roofs. As well, we are identifying and promoting effective asbestos management approaches with a focus on best practices and resources of most value in countries with limited occupational health resources. We are also contributing to international work on developing impact and cost data which provide the business case for remediation and other prevention action. Finally, we are partnering with colleagues in countries facing challenges around asbestos.