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We report a case of an active-duty diver who developed severe decompression sickness with concomitant patent foramen ovale that was successfully closed contrary to standard guideline recommendations. This case should prompt evaluation of the role of cardiac screening in occupational divers, including tactical athletes, relative to recreational divers. [ABSTRACT FROM AUTHOR]

The extraction of typical features of underwater target signals and excellent recognition algorithms are the keys to achieving underwater acoustic target recognition of divers. This paper proposes a feature extraction method for diver signals: frequency−domain multi−sub−band energy (FMSE), aiming to achieve accurate recognition of diver underwater acoustic targets by passive sonar. The impact of the presence or absence of targets, different numbers of targets, different signal−to−noise ratios, and different detection distances on this method was studied based on experimental data under different conditions, such as water pools and lakes. It was found that the FMSE method has the best robustness and performance compared with two other signal feature extraction methods: mel frequency cepstral coefficient filtering and gammatone frequency cepstral coefficient filtering. Combined with the commonly used recognition algorithm of support vector machines, the FMSE method can achieve a comprehensive recognition accuracy of over 94% for frogman underwater acoustic targets. This indicates that the FMSE method is suitable for underwater acoustic recognition of diver targets. [ABSTRACT FROM AUTHOR]

Cardiovascular responses to diving are characterized by two opposing responses: tachycardia resulting from exercise and bradycardia resulting from the apnea. The convergence of bradycardia and tachycardia may determine the cardiovascular responses to diving. The purpose of this study was to investigate the interaction of breath holding and muscle mechanoreflex on cardiovascular responses in breath-hold divers (BHDs) and non-BHDs. We compared the cardiovascular responses to combined apnea and the mechanoreflex in BHDs and non-BHDs. All participants undertook three trials—apnea, passive leg cycling (PLC), and combined trials—for 30 s after rest. Cardiovascular variables were measured continuously. Nine BHD (male:female, 4:5; [means ± SD] age, 35 ± 6 years; height, 168.6 ± 4.6 cm; body mass, 58.4 ± 5.9 kg) and eight non-BHD (male:female, 4:4; [means ± SD] age, 35 ± 7 years; height, 163.9 ± 9.1 cm; body mass, 55.6 ± 7.2 kg) participants were included. Compared to the resting baseline, heart rate (HR) and cardiac output (CO) significantly decreased during the combined trial in the BHD group, while they significantly increased during the combined trials in the non-BHD group (P < 0.05). Changes in the HR and CO were significantly lower in the BHD group than in the non-BHD group in the combined trial (P < 0.05). These results suggest that bradycardia with apnea in BHDs is prioritized over tachycardia with the mechanoreflex, whereas that in non-BHDs is not. This finding implies that diving training changes the interaction between apnea and the mechanoreflex in cardiovascular control. [ABSTRACT FROM AUTHOR]

Background: Temporomandibular disease (TMD) is commonly seen, and divers also experience pain in the temporomandibular joint (TMJ) or masticatory muscles. This article aims to provide a tool for diving physicians or medical professionals involved in diving medicine since jaw pain among divers is a pertinent subject and can be challenging to evaluate without some background in dentistry or maxillofacial surgery. Method: A basic algorithm was developed to provide a tool to differentiate jaw pains experienced by divers. Three brief case studies were developed, and five diving physicians were tasked with diagnosing the cases using the algorithm. Additionally, simple exercises and massage techniques that can benefit patients with TMD, particularly immediately after diving, are outlined. Results: All five diving physicians successfully diagnosed the cases using the algorithm. However, three of them were unable to diagnose the first case (disc luxation) without consulting the algorithm. Nevertheless, all physicians acknowledged the utility of the algorithm. Conclusions: Jaw pain in divers can stem from diverse causes, but effective treatment options exist. Our study findings provide valuable insights to assist diving physicians in making accurate diagnoses and guiding appropriate patient management, which may include referrals to specialists such as dentists, maxillofacial surgeons, or orthodontists. [ABSTRACT FROM AUTHOR]

Expert freediving explores the limits of human endurance, with some divers staying underwater for over 10 min or reaching crushing depths on a single breath. This article explores the enskilment process, especially how freediving training involves a suite of reflexive bodily practices with psychological, neurological, and physiological consequences. Examined closely and over time, skill acquisition is a multi‐dimensional process involving self‐driven adaptations in a cumulative, uneven manner. Because skills combine biological, cultural, and psychological mechanisms, practices are ideal for biocultural analysis in psychological anthropology. This account of the behavioral‐development spiral in freediving enskilment suggests that transformative practices are inherently developmental, with neurological consequences. Theories of practice that ignore the temporal dimension or the variability of skill acquisition, that is, accounts that erase the slow and uncertain accumulation of expertise, fundamentally misrepresent how persistent practice blends biology and culture, and causes transformation, as well as the usefulness of ethnography for studying these processes. [ABSTRACT FROM AUTHOR]

Explosive Ordnance Disposal (EOD) divers are that category of soldiers from the Naval Forces with tasks and missions, equipment and specific training, which ensure the removal of the danger generated by explosive devices. One of the basic missions of EOD divers is the fight against sea mines, which are the most frequently used explosive devices in naval confrontations. To win the war against mines, all specialized structures must be used, depending on the specifics of the mission, no matter if we are talking about specialized ships, aviation or EOD divers. [ABSTRACT FROM AUTHOR]

Fault detection in subsea pipelines is a difficult problem for several reasons, and one of the most important is the inaccessibility of the system. This criticality can be overcome by using transient test-based techniques. Such an approach is based on the execution of safe transients that result in small over pressures (i.e., on the order of a few meters of water column). In our companion paper, the procedure involving the transient tests was described in detail. This paper analyses the results of the field tests carried out and identifies wall deterioration in some sections of the pipeline. Attention is focused on the numerical procedure based on the joint use of a 1-D numerical model simulating transients in the pressurized flow and analytical relationships and providing the transient response of anomalies such as leaks and wall deterioration. The results obtained are essentially confirmed by the survey carried out by divers. [ABSTRACT FROM AUTHOR]

The risks of decompression sickness and its complications in professional divers and amateur divers with various methods of diving in real and simulated conditions are considered. The pathogenesis of disorders of the plasma and vascular hemostasis system under the influence of environmental factors on the body during various types of dives is discussed. Generalization of the research results showed that the mechanisms of activation of thrombosis under this influence are complex and are caused by microbubble-mediated platelet activation as well as by development of endothelial dysfunction, oxidative, and psychophysiological stress. The study of hemostasis parameters in professional and amateur divers can be one of the main methods of assessing the risk of its development. The considered means of preventing thrombosis during diving and decompression, according to the results of the studies included in the review, are quite effective. [ABSTRACT FROM AUTHOR]

The article discusses the impact of Jacques Cousteau and Emile Gagnan's invention, the Scaphandre Autonome or Aqua Lung, on the diving industry. The invention led to the development of open-circuit SCUBA diving and the creation of various diving equipment such as regulators, tanks, exposure suits, masks, fins, and accessories. The article also highlights the longevity of companies that have produced innovative diving gear, and provides a series of photographs showcasing Aqua Lung equipment. [Extracted from the article]

The article presents the results of a pilot programme to include psychological tests in the qualification rules for candidates for military divers and scuba divers. 207 candidates for training at the Polish Army Divers and Scuba Divers Training Centre were tested. They were subjected to mental fitness tests, personality tests, psychomotor fitness tests and general fitness tests. Numerous psychological contraindications to undertaking training and diving service were identified; the most common issue identified being a lack of robustness of the diver's mental state for dealing with the situations likely to be encountered in the water. The conclusions suggest that, as in other countries, psychological examinations should be included in the qualification of candidates for diving. The results of the tests, despite their non-mandatory nature, were partly taken into account in the opinion of the Military Maritime and Medical Commission. [ABSTRACT FROM AUTHOR]

Indigenous fisherman divers frequently experience decompression sickness (DCS). This study aimed to evaluate the associations between the level of knowledge of safe diving, beliefs in the health locus of control (HLC), and regular diving practices with DCS among the indigenous fisherman divers on Lipe island. The correlations among the level of beliefs in HLC, knowledge of safe diving and regular diving practices were evaluated also. We enrolled the fisherman divers on Lipe island and collected their demographics, health indices, levels of knowledge of safe diving, beliefs in external and internal HLC (EHLC and IHLC), and regular diving practices to evaluate the associations with the occurrence of DCS by logistic regression analysis. Pearson's correlation was used to test the correlations among the level of beliefs in IHLC and EHLC, knowledge of safe diving, and regular diving practices. Fifty-eight male fisherman divers whose mean age was 40.39 (±10.61) (range 21–57) years were enrolled. Twenty-six (44.8%) participants had experienced DCS. Body mass index (BMI), alcohol consumption, diving depth, duration of time in the sea/dive, level of beliefs in HLC and regular diving practices were significantly associated with DCS (p < 0.05). Level of belief in IHLC had a significantly strong reverse correlation with that in EHLC and a moderate correlation with level of knowledge of safe diving and regular diving practices. By contrast, level of belief in EHLC had a significantly moderate reverse correlation with level of knowledge of safe diving and regular diving practices (p < 0.001). Encouraging the fisherman divers' belief in IHLC could be beneficial for their occupational safety. [ABSTRACT FROM AUTHOR]

Sabbaticals have seen an exponential growth in adoption over the last two decades and are ascribed extensive benefits by employers and employees alike. Little is known, however, about how individuals spend their time or how their experiences impact them after they return to work. Drawing on narrative interviews with 50 diverse professionals, we discover that sabbaticals combine "building blocks"− distinct periods dedicated to recover, explore, or practice− into three typical trajectories: working holidays (alternating recovery and practice), free dives (alternating recovery and exploration), and quests (unfolding from recovery to exploration to practice). While participants returned from all sabbaticals feeling affirmed in their own voice, periods of exploration and practice were associated with the extent to which sabbaticals fundamentally changed their self-narrative and disrupted the trajectory of their working lives. Those on working holidays tended to return to their former lives (though with a greater confidence and need for balance), while free divers pursued better fitting but similar work (e.g., a change in position or employer), and questers were most likely to make drastic career changes. Our model extends the breaks literature and authenticity scholarship, and offers insights to those considering a sabbatical. [ABSTRACT FROM AUTHOR]

Introduction: While gas narcosis is familiar to most divers conducting deep (> 30 metres) dives, its effects are often considered minuscule or subtle at 30 metres. However, previous studies have shown that narcosis may affect divers at depths usually considered safe from its influence, but little knowledge exists on the effects of gas narcosis on higher cognitive functions such as decision-making in relatively shallow water at 30 metres. Impaired decision-making could be a significant safety issue for a multitasking diver. Methods: We conducted a study exploring the effects of gas narcosis on decision-making in divers breathing compressed air underwater. The divers (n = 22) were evenly divided into 5-metre and 30-metre groups. In the water, we used underwater tablets equipped with the Iowa Gambling Task (IGT), a well-known psychological task used to evaluate impairment in decision-making. Results: The divers at 30 metres achieved a lower score (mean 1,584.5, standard deviation 436.7) in the IGT than the divers at 5 metres (mean 2,062.5, standard deviation 584.1). Age, body mass index, gender, or the number of previous dives did not affect performance in the IGT. Conclusions: Our results suggest that gas narcosis may affect decision-making in scuba divers at 30 metres depth. This supports previous studies showing that gas narcosis is present at relatively shallow depths and shows that it may affect higher cognitive functions. [ABSTRACT FROM AUTHOR]

Introduction: Air flow in full-face snorkel masks (FFSMs) should be unidirectional to prevent rebreathing of exhaled air. This study evaluated rebreathing and its consequences when using FFSMs compared to a conventional snorkel. Methods: In a dry environment 20 participants wore three types of snorkel equipment in random order: Subea Easybreath FFSM; QingSong 180-degree panoramic FFSM; and a Beuchat Spy conventional snorkel (with nose clip), in three conditions: rest in a chair; light; and moderate intensity exercise on a cycle ergometer. Peripheral oxygen saturation, partial pressure of carbon dioxide (PCO2) and oxygen (PO2) in the end tidal gas and FFSM eye-pockets, respiratory rate, minute ventilation, were measured continuously. Experiments were discontinued if oxygen saturation dropped below 85%, or if end-tidal CO2 exceeded 7.0 kPa. Results: Experimental runs with the FFSMs had to be discontinued more often after exceeding 7.0 kPa end-tidal CO2 compared to a conventional snorkel e.g., 18/40 (45%) versus 4/20 (20%) during light intensity exercise, and 9/22 (41%) versus 3/16 (19%) during moderate intensity exercise. Thirteen participants exhibited peripheral oxygen saturations below 95% (nine using FFSMs and four using the conventional snorkel) and five fell below 90% (four using FFSMs and one using the conventional snorkel). The PCO2 and PO2 in the eye-pockets of the FFSMs fluctuated and were significantly higher and lower respectively than in inspired gas, which indicated rebreathing in all FFSM wearers. Conclusions: Use of FFSMs may result in rebreathing due to non-unidirectional flow, leading to hypercapnia and hypoxaemia. [ABSTRACT FROM AUTHOR]

Without an adequate supply of oxygen from the scuba apparatus, humans would not be able to dive. The air normally contained in a scuba tank is dry and free of toxic gases. The presence of liquid in the tank can cause corrosion and change the composition of the gas mixture. Various chemical reactions consume oxygen, making the mixture hypoxic. We report two cases of internal corrosion of a scuba cylinder rendering the respired gas profoundly hypoxic and causing immediate hypoxic loss of consciousness in divers. [ABSTRACT FROM AUTHOR]

Introduction: Venous gas emboli (VGE) are widely used as a surrogate endpoint instead of decompression sickness (DCS) in studies of decompression procedures. Peak post-dive VGE grades vary widely following repeated identical dives but little is known about how much of the variability in VGE grades is proportioned between-diver and within-diver. Methods: A retrospective analysis of 834 man-dives on six dive profiles with post-dive VGE measurements was conducted under controlled laboratory conditions. Among these data, 151 divers did repeated dives on the same profile on two to nine occasions separated by at least one week (total of 693 man-dives). Data were analysed for between- and within-diver variability in peak post-dive VGE grades using mixed-effect models with diver as the random variable and associated intraclass correlation coefficients. Results: Most divers produced a wide range of VGE grades after repeated dives on the same profile. The intraclass correlation coefficient (repeatability) was 0.33 indicating that 33% of the variability in VGE grades is between-diver variability; correspondingly, 67% of variability in VGE grades is within-diver variability. DCS cases were associated with an individual diver's highest VGE grades and not with their lower VGE grades. Conclusions: These data demonstrate large within-diver variability in VGE grades following repeated dives on the same dive profile and suggest there is substantial within-diver variability in susceptibility to DCS. Post-dive VGE grades are not useful for evaluating decompression practice for individual divers. [ABSTRACT FROM AUTHOR]

Introduction: To develop the diving capacity in the Swedish armed forces the current air decompression tables are under revision. A new decompression table named SWEN21 has been created to have a projected risk level of 1% for decompression sickness (DCS) at the no stop limits. The aim of this study was to evaluate the safety of SWEN21 through the measurement of venous gas emboli (VGE) in a dive series. Methods: A total 154 dives were conducted by 47 divers in a hyperbaric wet chamber. As a proxy for DCS risk, serial VGE measurements by echocardiography were conducted and graded according to the Eftedal-Brubakk scale. Measurements were made every 15 minutes for approximately 2 hours after each dive. Peak VGE grades for the different dive profiles were used in a Bayesian approach correlating VGE grade and risk of DCS. Symptoms of DCS were continually monitored. Results: The median (interquartile range) peak VGE grade after limb flexion for a majority of the time-depth combinations, and of SWEN21 as a whole, was 3 (3-4) with the exception of two decompression profiles which resulted in a grade of 3.5 (3-4) and 4 (4-4) respectively. The estimated risk of DCS in the Bayesian model varied between 4.7-11.1%. Three dives (2%) resulted in DCS. All symptoms resolved with hyperbaric oxygen treatment. Conclusions: This evaluation of the SWEN21 decompression table, using bubble formation measured with echocardiography, suggests that the risk of DCS may be higher than the projected 1%. [ABSTRACT FROM AUTHOR]

This paper presents a target perception framework aimed at enhancing diver safety and facilitating underwater operations by extracting critical information from underwater scenes. The framework employs a layered processing approach, which encompasses water column imaging, constant false alarm rate detection, and local feature analysis. To simulate the diver's underwater environment, we conducted experiments with three distinct fields of view: fixed down-looking, fixed front-looking, and mobile side-looking perspectives. Our experimental findings demonstrate the framework's ability to accurately differentiate between false targets, stationary targets, and moving targets within the underwater scenes, as well as to capture the motion trajectories of dynamic targets. Furthermore, the application of 3D reconstruction techniques to underwater scene data enables the generation of approximate stereoscopic representations of divers and bubble groups. [ABSTRACT FROM AUTHOR]

The ability of echolocating toothed whales to detect and classify prey at long ranges enables efficient searching and stalking of sparse prey in these time-limited dives. However, nonecholocating deep-diving seals such as elephant seals appear to have much less sensory advantage over their prey. Both elephant seals and their prey rely on visual and hydrodynamic cues that may be detectable only at short ranges in the deep ocean, leading us to hypothesize that elephant seals must adopt a less efficient reactive mode of hunting that requires high prey densities. To test that hypothesis, we deployed high-resolution sonar and movement tags on 25 females to record simultaneous predator and prey behavior during foraging interactions. We demonstrate that elephant seals have a sensory advantage over their prey that allows them to potentially detect prey 5 to 10 s before striking. The corresponding prey detection ranges of 7 to 17 m enable stealthy approaches and prey-specific capture tactics. In comparison, prey react at a median range of 0.7 m, close to the neck extension range of striking elephant seals. Estimated search swathes of 150 to 900 m² explain how elephant seals can locate up to 2,000 prey while swimming more than 100 km per day. This efficient search capability allows elephant seals to subsist on prey densities that are consonant with the deep scattering layer resources estimated by hydroacoustic surveys but which are two orders of magnitude lower than the prey densities needed by a reactive hunter. [ABSTRACT FROM AUTHOR]

In the following article the binary understanding of gender identity will be opposed to polymorph imprint and concept of divers gender identities. How this development in the society can be understood and how it is been reflected in the psychoanalytic theory so far will be traced in the selected psychoanalytic theories of Monika Gsell and Markus Zürcher (2011) resp. Monika Gsell and Ralf Binswanger (2012) und their re-reading of Sigmund Freud, Ilka Quindeau (2017) and Letitia Glocer Fiorini (2018). [ABSTRACT FROM AUTHOR]

(β‐Diazo‐α,α‐difluoroethyl)phosphonates have been emerging as useful building blocks in organic synthetic chemistry in recent years, which can be used as diazo analog or masked carbene for the rapid assembly of difluoromethylene phosphonate‐containing compounds. Herein, we elaborate a method for the synthesis of α‐fluoro‐β‐ketophosphonates from hydration/C−F bond cleavage of in situ generated (β‐amino‐α,α‐difluoroethyl)phosphonates via a Rh‐carbene intermediate. Divers (β‐amino‐α,α‐difluoroethyl)phosphonates are tolerated in this reaction affording α‐fluoro‐β‐ketophosphonates in good yields. This reaction used the in situ generated water as the coupling partner, which represents a reaction of (β‐diazo‐α,α‐difluoroethyl)phosphonates and also a method for generating bioactive α‐fluoro‐β‐ketophosphonates. [ABSTRACT FROM AUTHOR]

The colour of seawater is a topic of daily discussion among diver fishermen in the Dominican Republic, who navigate shifting ocean environments alongside conservation politics. While conservation policies often target fishing as the main cause of declines in the health of marine ecologies, fishermen use colour to create alternative narratives about changing climates. Describing the sea as blue, black, brown, green, whitewash, purple, and chocolate, divers point to the broader causes of shifting seascapes while chronicling their affective and embodied consequences. Based on ethnographic fieldwork among Dominican diver fishermen, this article explores the colour of seawater as a lens for understanding the physical, affective, social, and political consequences of changing climates for communities who are deeply entangled in shifting sea ecologies. For diver fishermen, whose engagements with the sea depend on visibility, colours provide ways of interpreting fishing possibilities, navigating ocean spaces, and measuring the effects of changing environments. Given the centrality of colour perception in fishermen's lives, this article argues that colours provide an alternative narrative about changing climates, linking shifting marine conditions to global systemic problems, rather than blaming changes in environmental conditions on supposedly irresponsible practices of local people. [ABSTRACT FROM AUTHOR]

Passive acoustic density estimation has been gaining traction in recent years. Cue counting uses detected acoustic cues to estimate animal abundance. A cue rate, the number of acoustic cues produced per animal per unit time, is required to convert cue density into animal density. Cue rate information can be obtained from animal borne acoustic tags. For deep divers, like beaked whales, data have been analyzed considering deep dive cycles as a natural sampling unit, based on either weighted averages or generalized estimating equations. Using a sperm whale DTAG (sound-and-orientation recording tag) example we compare different approaches of estimating cue rate from acoustic tags illustrating that both approaches used before might introduce biases and suggest that the natural unit of analysis should be the whole duration of the tag itself. [ABSTRACT FROM AUTHOR]

Copyright of Journal of the Royal Anthropological Institute is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: In 2018, the Belgian Defence introduced a commercial off-the-shelf dive computer (Shearwater Perdix™) for use by its military divers. There were operational constraints when using its default gradient factors (GF). We aimed to provide guidelines for optimal GF selection. Methods: The Defence and Civil Institute of Environmental Medicine (DCIEM) dive tables and the United States Navy (USN) air decompression tables are considered acceptably safe by the Belgian Navy Diving Unit. The decompression model used in the Shearwater Perdix (Bühlmann ZH-L16C algorithm with GF) was programmed in Python. Using a sequential search of the parameter space, the GF settings were optimised to produce decompression schedules as close as possible to those prescribed by the USN and DCIEM tables. Results: All reference profiles are approached when GFLO is kept equal to 100 and only GFHI is reduced to a minimum of 75 to prolong shallower stop times. Using the Perdix default settings (GFLO = 30 and GFHI = 70) yields deeper initial stops, leading to increased supersaturation of the 'slower' tissues, which potentially leads to an increased DCS risk. However, Perdix software does not currently allow for the selection of our calculated optimal settings (by convention GFLO < GFHI). A sub-optimal solution would be a symmetrical GF setting between 75/75 and 95/95. Conclusions: For non-repetitive air dives, the optimal GF setting is GFLO 100, with only the GFHI parameter lowered to increase safety. No evidence was found that using the default GF setting (30/70) would lead to a safer decompression for air dives as deep as 60 metres of seawater; rather the opposite. Belgian Navy divers have been advised against using the default GF settings of the Shearwater Perdix dive computer and instead adopt symmetrical GF settings which is currently the optimal achievable approach considering the software constraints. [ABSTRACT FROM AUTHOR]

Some divers who use scuba equipment experience decompression illness. Previous articles reported a higher prevalence of patent foramen ovale in divers who experience decompression illness, although the studies were relatively small. This article describes the frequency of patent foramen ovale and decompression illness in 100 divers who did more than 50 dives per year in 8 countries. Visual Abstract. Decompression Illness in Divers With or Without Patent Foramen Ovale: Some divers who use a self-contained underwater breathing apparatus (SCUBA) experience decompression illness. Previous articles reported a higher prevalence of patent foramen ovale in divers who experience decompression illness, although the studies were relatively small. This article describes the frequency of patent foramen ovale and decompression illness in 100 divers who did more than 50 dives per year in 8 countries. Background: In previous studies, the prevalence of patent foramen ovale (PFO) has been reported to be higher in scuba divers who experienced decompression illness (DCI) than in those who did not. Objective: To assess the association between PFO and DCI in scuba divers. Design: Prospective cohort study. Setting: Tertiary cardiac center in South Korea. Participants: One hundred experienced divers from 13 diving organizations who did more than 50 dives per year. Measurements: Participants had transesophageal echocardiography with a saline bubble test to determine the presence of a PFO and were subsequently divided into high- and low-risk groups. They were followed using a self-reported questionnaire while blinded to their PFO status. All of the reported symptoms were adjudicated in a blinded manner. The primary end point of this study was PFO-related DCI. Logistic regression analysis was done to determine the odds ratio of PFO-related DCI. Results: Patent foramen ovale was seen in 68 divers (37 at high risk and 31 at low risk). Patent foramen ovale–related DCI occurred in 12 divers in the PFO group (non-PFO vs. high-risk PFO vs. low-risk PFO: 0 vs. 8.4 vs. 2.0 incidences per 10 000 person-dives; P  = 0.001) during a mean follow-up of 28.7 months. Multivariable analysis showed that high-risk PFO was independently associated with an increased risk for PFO-related DCI (odds ratio, 9.34 [95% CI, 1.95 to 44.88]). Limitation: The sample size was insufficient to assess the association between low-risk PFO and DCI. Conclusion: High-risk PFO was associated with an increased risk for DCI in scuba divers. This finding indicates that divers with high-risk PFO are more susceptible to DCI than what has been previously reported and should consider either refraining from diving or adhering to a conservative diving protocol. Primary Funding Source: Sejong Medical Research Institute. [ABSTRACT FROM AUTHOR]

The article focuses on Wendy Ayres-Bennett's critical edition of Claude Favre de Vaugelas' "Remarques de la langue françoise," a significant linguistic and cultural text from the 17th century. Topics include Vaugelas' influential role among 17th-century French language commentators, the publication history and significance of "Remarques," and Ayres-Bennett's commentary and critical edition.

Copyright of Revista Austral de Ciencias Sociales is the property of Facultad de Filosofia y Humanidades, Intituto de Ciencias Sociales, Universidad Austral de Chile and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aim of the study was to determine totoxicity of bisphenol A (BPA) and its derivatives (bisphenol S (BPS), bisphenol F (BPF), and tetrabromobisphenol A (TBBPA)) due to its high accumulation in environment. The performed analysis revealed the toxicity of the BPA, BPF, and BPS against Kurthia gibsoni, Microbacterium sp., and Brevundimonas diminuta as the most sensitive, reaching microbial toxic concentrations in the range of 0.018–0.031 mg ∙ L−1. Moreover, the genotoxicity assay shows the ability of all tested compounds to increase in the β-galactosidase level at the concentration range 7.81–500 µM (in Escherichia coli, PQ37). In turn, the matbolic activation of tested bishpenols has caused the enhacement of the genotoxicity and cytotoxicity effect. Interestingely, the highest phytotoxicity effect was pointed for BPA and TBBPA at the concentrations of 10 mg ∙ L−1 and 50 mg ∙ L−1, which cause the inhibition of root growth by 58% and 45%, respectively (especially for S. alba and S. saccharatum). Furthermore, the cytotoxicity analyses show the ability of BPA, BPS, and TBBPA to significantly decrease the metabolic activity of human keratynoctes in vitro after 24 h of treatment at the micromolar concentrations. Simialry, the impact of the certain bisphenols on proliferation-, apoptosis-, and inflammation-related mRNA expression was shown in tested cell line. Summarizing, the presented results have proved that BPA and its derrivatives are able to show high negative effect on certain living orgnisms such as bacteria, plants, and human cells, which is strict related to pro-apoptotic and genotoxic mechanism of action. [ABSTRACT FROM AUTHOR]

While the circular economy invites us to realize the potential of the so-called 'waste-based commodity frontiers', reintegration into capitalist value chains is not the only way for discards to be resurrected. In this article, we examine the ways in which the collective of dumpster divers is organized in relation to giving, receiving and reciprocating of various waste-gifts. Our intention is not only to expand existing theorizations of the gift to new domains but also to critically interrogate them, identify their limitations and explore what dumpster diving can teach us about the gift. In particular, the analysis foregrounds the heterogeneity of gift practices. Arguing against universal notions of the gift, the article proposes that waste assumes four main forms of gifts and relations among dumpster divers: givenness (parasitic relation); solidarity-based giving (relation of reciprocity); free giving (asymmetrical relation); and non-giving, as a withdrawal from returning the discards to nature conceived as an Other (the relation of non-relation). [ABSTRACT FROM AUTHOR]

Introduction: This study aimed to develop a standard process and checklist for technical investigation of hookah diving equipment and apply it to Tasmanian hookah fatality investigations from the last 25 years. Methods: A literature search was undertaken to identify technical reports and equipment investigations associated with diving accidents. The information was assimilated to create a process and checklist for specifically assessing the hookah apparatus. The checklist was then applied in a gap analysis of Tasmanian hookah diving fatality technical reports from 1995 to 2019. Results: As no papers specifically describing technical evaluation of hookah equipment were identified, references evaluating scuba equipment were used to create a hookah technical assessment process incorporating unique features of the hookah. Features included: owner responsibility for air quality; maintenance, function; exhaust proximity to air intake; reservoir volume; output non-return valves; line pressure; sufficiency of supply; entanglement; hose severance risk; gas supply failure and hosing attachment to the diver. Seven hookah diving deaths occurred in Tasmania (1995−2019) of which three had documented technical assessment. Gap analysis identified inconsistent structure between reports with variability in the case descriptors. Missing technical data included: overview of the hookah systems; accessories; weights; how the apparatus was worn by the diver; compressor suitability; assessment of hookah function; breathing gas output and exhaust position relative to air intake. Conclusions: The study demonstrated a need to standardise technical reporting of hookah equipment after diving accidents. The checklist generated may serve as a resource for future hookah assessments and inform strategies for preventing future hookah accidents. [ABSTRACT FROM AUTHOR]

Cerebral white-matter lesions (cWML) can be caused by dilation of Virchow–Robin spaces or may correspond to true lacunar ischemic lesions. The aim of our study was to evaluate in asymptomatic divers the relationship between the presence of patent foramen ovale (PFO) and cWML, as well as their possible effects on cortical cerebral blood flow (CBF) by magnetic resonance (MRI) through the arterial spin labeling (ASL) sequence. Transthoracic echocardiography was performed for the identification of PFO, and cerebral magnetic resonance including the 3D-ASL sequence for CBF quantification. Thirty-eight divers, with a mean age 45.8 ± 8.6 years, were included. Nineteen healthy volunteers, mean age 41 ± 15.2 years, served as the control group. A total of 28.9% of divers had completed more than 1000 dives. It was found that 26.3% of divers presented with PFO in the echocardiographic study. cWML was evidenced in 10.5% of diver MRI studies. There was no statistically significant relationship between the presence of PFO and cWML (p = 0.95). We observed a lower blood flow in all brain areas assessed by the 3D-ASL sequence in the group of divers, compared with the control group. We did not find statistical differences in CBF as a function of the presence or absence of PFO, number of dives, or cWML evidence. [ABSTRACT FROM AUTHOR]

Introduction: In this study, we aimed to examine dental barotrauma and temporomandibular joint (TMJ) complaints in a large group of divers. Method: This survey study included scuba divers older than 18. The questionnaire contained 25 questions about the demographic characteristics of divers, dental health behaviors, and diving-related dental, sinus and/or temporomandibular joint pain Results: The study group consisted of 287 instructors, recreational and commercial divers (mean age 38.96 years) (79.1% males). A total of 46% of divers reported a frequency of tooth brushing less than twice a day; 28% never receive a routine dental examination; 22.6% experienced dental pain after and/or during diving, mostly in the upper posterior teeth (40%); 17% required dental treatment; 77% of these cases are restoration fracture. TMJ symptoms after diving were statistically significantly higher in women (p=0.04). Jaw and masticatory muscle pain in the morning (p<0.001) limitation of mouth opening (p=0.04) and joint sounds in daily life (p<0.001) were recorded as exacerbated after diving; the results were found to be statistically significant. Conclusion: In our study, the localization of barodontalgia was consistent with the distribution of caries and restored tooth areas in the literature. Dive-related TMJ pain was also more common in those with pre-dive problems such as bruxism and joint noise. Our results are important to remind us of the necessity of preventive dentistry practices and early diagnosis of problems in divers. Divers should take personal precautions, such as brushing their teeth twice a day and avoiding the need for urgent treatment. The use of a personalized mouthpiece is also recommended for divers to prevent dive-related temporomandibular joint diseases. [ABSTRACT FROM AUTHOR]

Blood-borne extracellular vesicles and inflammatory mediators were evaluated in divers using a closed circuit rebreathing apparatus and custom-mixed gases to diminish some diving risks. "Deep" divers (n = 8) dove once to mean (±SD) 102.5 ± 1.2 m of sea water (msw) for 167.3 ± 11.5 min. "Shallow" divers (n = 6) dove 3 times on day 1, and then repetitively over 7 days to 16.4 ± 3.7 msw, for 49.9 ± 11.9 min. There were statistically significant elevations of microparticles (MPs) in deep divers (day 1) and shallow divers at day 7 that expressed proteins specific to microglia, neutrophils, platelets, and endothelial cells, as well as thrombospondin (TSP)-1 and filamentous (F-) actin. Intra-MP IL-1β increased by 7.5-fold (p < 0.001) after day 1 and 41-fold (p = 0.003) at day 7. Intra-MP nitric oxide synthase-2 (NOS2) increased 17-fold (p < 0.001) after day 1 and 19-fold (p = 0.002) at day 7. Plasma gelsolin (pGSN) levels decreased by 73% (p < 0.001) in deep divers (day 1) and 37% in shallow divers by day 7. Plasma samples containing exosomes and other lipophilic particles increased from 186% to 490% among the divers but contained no IL-1β or NOS2. We conclude that diving triggers inflammatory events, even when controlling for hyperoxia, and many are not proportional to the depth of diving. [ABSTRACT FROM AUTHOR]

Central place foragers such as pelagic seabirds often travel large distances to reach profitable foraging areas. King penguins (Aptenodytes patagonicus) are well known for their large-scale foraging movements to the productive Antarctic Polar Front, though their fine-scale travelling and foraging characteristics remain unclear. Here, we investigated the horizontal movements and foraging patterns of king penguins to understand their fine-scale movement decisions during distant foraging trips. We attached multi-channel data loggers that can record depth, speed, tri-axis acceleration, tri-axis magnetism, and environmental temperature of the penguins and obtained data (n = 8 birds) on their horizontal movement rates from reconstructed dive paths and their feeding attempts estimated from rapid changes in swim speed. During transit toward main foraging areas, penguins increased the time spent on shallow travelling dives (< 50 m) at night and around midday, and increased the time spent on deep foraging dives (≥ 50 m) during crepuscular hours. The horizontal movement rates during deep dives were negatively correlated with maximum dive depths, suggesting that foraging at greater depths is associated with a decreased horizontal travelling speed. Penguins concentrated their foraging efforts (more deep dives and higher rates of feeding attempts) at twilight during transit, when prey may be more accessible due to diel vertical migration, while they travelled rapidly at night and midday when prey may be difficult to detect and access. Such behavioural adjustments correspond to a movement strategy adopted by avian deep divers to travel long distances while feeding on prey exhibiting diel vertical migration. [ABSTRACT FROM AUTHOR]

Using the wreck of the galleon Nuestra Señora de Las Maravillas (1656) as a point of departure, this article analyzes the role of Cartagena de Indias as a logistical center for fraudulent silver salvaging and transportation in the Spanish Caribbean during the middle of the seventeenth century. After 1640, Cartagena's insertion into Atlantic maritime networks suffered from the collapse of Portuguese-led slave trading, the decline in legal silver circulation in Spanish ports, and expansion of other European colonial powers across the Caribbean. The article uses the cases made against officials and contractors involved in unauthorized silver salvaging in Cartagena to show how Caribbean-based Spanish merchants and administrators created trans-Atlantic bullion transportation networks independent of royal control. Like their legal counterparts, these unauthorized networks relied on specialized maritime labor from free and unfree divers of African and Amerindian origin, and sailors of all races. Simultaneously, maritime laborers' knowledge, often extracted under torture, formed the basis of prosecutors' cases against suspect colonial officials. By following these maritime linkages, this article highlights the centrality of maritime labor and communication logistics in the structural rearrangement of the Caribbean during the seventeenth century. [ABSTRACT FROM AUTHOR]