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Healthy oceans are essential for life, but a mere 2.9% are fully protected. The question then arises why is ocean protection so challenging? Among the many reasons is the economic allure of extractive activities which poses a barrier to alleviating human pressure on ocean areas. Marine protected areas (MPAs), primarily designed to preserve biodiversity, are often rationalized through a business lens and are expected to yield revenue by increasing tourists’ willingness to pay. However, MPAs are not business entities and require a set of enabling conditions to successfully reach their goals. In a successful marine protected area, a unit increase in natural capital results in a rise in tourist revenue. We developed a bioeconomic model to show how fully protecting diving sites can significantly enhance nature’s recovery and lead to larger revenues for the scuba diving industry. In Mexico, scuba diving generates as much revenue as the fishing industry, yet only 7% of the country’s diving sites are fully protected. Globally, the scuba diving industry generates up to $20 billion dollars per year, even though about half of the diving sites worldwide lack protection. Using global experiences, we designed a five-step bottom-up approach that scuba diving operators can use to amplify marine protection. This approach could catalyze the creation of stricter or new fullyprotected areas designed to incorporate existing businesses a significant departure from the traditional business framework. The Atlas Aquatica initiative advocates for a significant shift in narrative to stimulate broader acceptance of marine protection worldwide. We aim to contribute to a sustainable blue economic growth and the 30x30 conservation target by promoting the protection of diving sites globally.

The article "Matching the Dispersal of Baby Clownfish to Oceanographic Currents" explores how ocean currents influence the dispersal of yellowtail clownfish larvae in the central Philippines. By genetically matching offspring to parents, researchers found that while ocean currents play a role in dispersal patterns, other factors such as swimming and navigation also contribute to how far the larvae disperse. The study provides insights into how dispersal variation impacts population persistence and local adaptation in marine species. [Extracted from the article]

The first record of the kelp species Phyllariopsis brevipes in the Campania Region (Tyrrhenian Sea, South Italy) is here reported. The species has been observed in October 2021 in four sites along Sorrento Peninsula and Capri Island coast during scuba diving surveys. P. brevipes grew on living thalli of crustose coralline algae from 32 up to 55 m depth, occasionally forming dense aggregations with a maximum cover of about 0.2 m2. The DNA barcoding analysis on the basis of the cox1 gene supported the identification, with 98.36% of similarity between the sample collected in this study (NCBI accession number: PP622796) and a sequence obtained from a specimen from Provence, Mediterranean France (NCBI accession number: GQ368264). The study area can be considered a stepping stone for the species dispersion. The occurrence of P. brevipes can be related to upwelling and good water quality and the monitoring of its health status might be a sentinel of environmental changes. [ABSTRACT FROM AUTHOR]

This study reports the presence of the ragged sea hare Bursatella leachii de Blainville 1817 in the Black Sea. A total of 484 specimens of this species were observed during scuba diving and snorkeling at depths ranging from 1.0 to 4.0 meters in September 2023. The samples were observed on the sandy-muddy bottom of Kumbaba Beach and the sandy bottom of Uzunkum Beach in Şile district (Istanbul province). The density of individuals per square meter of the seabed was calculated and the highest number of individuals was detected on the Kumbaba Beach near the mouth of the Türknil River. Considering the location of discovery, it is logical to assume that the introduction of this species into the Black Sea may have occurred naturally. This hypothesis can be supported for two main reasons; a) Şile beaches are a few kilometers away from the Bosphorus Channel, b) the report of B. leachii closest to Şile district dates back to January 2020, when the species was observed on the seabed on the southern coast of the Dardanelles. Long-term monitoring and more in-depth studies should be conducted in the region to give certainty to these hypotheses. [ABSTRACT FROM AUTHOR]

This paediatric diving position statement was developed from a targeted workshop at the 51st Annual Scientific Meeting of the South Pacific Underwater Medicine Society (SPUMS) on 8 June 2023. It highlights the factors that SPUMS regards as important when undertaking health risk assessments for diving by children and adolescents (defined as aged 10 to 15 years). Health risk assessments for diving should be performed by doctors who are trained in diving medicine and who are familiar with the specific risks which result from breathing compressed gas in the aquatic environment. Undertaking a diver health risk assessment of children and adolescents requires a detailed history (including medical, mental health, psychological maturity), a comprehensive diver medical physical examination and evaluation of all relevant investigations to exclude unacceptable risks. In addition, assessment of the individual's motivation to dive and reported in-water capability should occur, whilst engaging with their parent /guardian and instructor, where appropriate, to ensure that safety for the child is optimised. The guideline applies to all compressed air diving including scuba and surface supply diving provided in open and contained bodies of water. [ABSTRACT FROM AUTHOR]

Introduction: Hyperbaric oxygen treatment (HBOT) is considered definitive treatment for decompression illness. Delay to HBOT may be due to dive site remoteness and limited facility availability. Review of cases may help identify factors contributing to clinical outcomes. Methods: Injured divers treated in Townsville from November 2003 through December 2018 were identified. Information on demographics, initial disease severity, time to symptom onset post-dive, time to pre-HBOT oxygen therapy (in-water recompression or normobaric), time to HBOT, and clinical outcome was reviewed. Data were reported as median (interquartile range [IQR]) with Kruskal-Wallis and chi-square tests used to evaluate group differences. Significance was accepted at P < 0.05. Results: A total of 306 divers (184 males, 122 females) were included with a median age of 29 (IQR 24, 35) years. Most divers had mild initial disease severity (n = 216, 70%). Time to symptom onset was 60 (10, 360) min, time to pre-HBOT oxygen therapy was 4:00 (00:30, 24:27) h:min, and time to start of HBOT was 38:51 (22:11, 69:15) h:min. Most divers (93%) had a good (no residual or minor residual symptoms) outcome and no treated diver died. Higher initial disease severity was significantly associated with shorter times to symptom onset, oxygen therapy, and HBOT, and with worse outcomes. The paucity of cases receiving HBOT with minimal delay precluded meaningful evaluation of the effect of delay to HBOT. Conclusions: Most divers had mild initial disease severity and a good outcome. Higher initial disease severity accelerated the speed of care obtained and was the only factor associated with poorer outcome. [ABSTRACT FROM AUTHOR]

This joint position statement (JPS) on immersion pulmonary oedema (IPO) and diving is the product of a workshop held at the 52nd Annual Scientific Meeting of the South Pacific Underwater Medicine Society (SPUMS) from 12-17 May 2024, and consultation with the United Kingdom Diving Medical Committee (UKDMC), three members of which attended the meeting. The JPS is a consensus of experts with relevant evidence cited where available. The statement reviews the nomenclature, pathophysiology, risk factors, clinical features, prehospital treatment, investigation of and the fitness for future compressed gas diving following an episode of IPO. Immersion pulmonary oedema is a life-threatening illness that requires emergency management as described in this statement. A diver with previous suspected or confirmed IPO should consult a medical practitioner experienced in diving medicine. The SPUMS and the UKDMC strongly advise against further compressed gas diving if an individual has experienced an episode of IPO. [ABSTRACT FROM AUTHOR]

Rothera is a British Antarctic Survey research station located on Adelaide Island adjacent to the Antarctic Peninsula. Diving is vital to support a long-standing marine science programme but poses challenges due to the extreme and remote environment in which it is undertaken. We summarise the diving undertaken and describe the medical measures in place to mitigate the risk to divers. These include pre-deployment training in the management of emergency presentations and assessing fitness to dive, an on-site hyperbaric chamber and communication links to contact experts in the United Kingdom for remote advice. The organisation also has experience of evacuating patients, should this be required. These measures, as well as the significant infrastructure and logistical efforts to support them, enable high standards of medical care to be maintained to divers undertaking research on this most remote continent. [ABSTRACT FROM AUTHOR]

Gastric perforation secondary to barotrauma is a rare surgical condition which may manifest as an acute abdomen and potentially lead to complications such as pneumoperitoneum. A 50-year-old, healthy, experienced diving instructor was transported to our emergency department for an acute abdomen and severe dyspnoea after a diving incident. Clinical suspicion combined with computed tomography scanning lead to the diagnosis of linear rupture of the stomach. Exsufflation of the abdominal cavity was performed in the emergency department and then the patient was sent to the operating room for emergency laparoscopic gastric repair. Post-operative management was focused on decompressing the stomach with a nasogastric tube and abdominal radiography with barium ingestion was performed to confirm the absence of leakage. The patient was discharged at postoperative day four. We found 16 similar cases in the published literature. Gastric perforation secondary to a diving accident is rare but requires rapid diagnosis and surgical treatment. [ABSTRACT FROM AUTHOR]

Introduction: A 54-year-old, previously healthy Caucasian male diver was on a 22-day liveaboard diving holiday. During this time, he performed 75 open-circuit dives, of which 72 were with enriched air nitrox. All dives were within recreational length and depth. After the trip he noticed a worsening of vision and his refraction had changed from the previous -3.75/-5.75 to -5.5/-7.75 dioptres. Hyperoxic myopia is a well-known phenomenon after hyperbaric oxygen treatment (HBOT), but related literature in recreational divers is scarce. Methods: A systematic literature review on the effect of a hyperoxic environment on the development of myopia was done according to the PRISMA guidelines. Three databases were searched: Ovid MEDLINE, Scopus, and the Cochrane Library. A risk of bias analysis was done on all articles, and the GRADE approach was used to evaluate the quality of evidence. Articles that had sufficient data were used to synthesise a visualisation of oxygen exposure and changes in refraction. Results: Twenty-two articles were included in this review. These included five case reports, two case series, nine cohort studies, one randomised controlled trial and five reviews, of which one was systematic. Most articles described HBOT patients' ocular complications, although four articles were diver centric. The synthesis of results suggests that divers tend to get a greater myopic shift with a smaller exposure. However, the data were too heterogeneous to perform meaningful statistical analyses. This review is the first to focus on divers instead of HBOT patients. Conclusions: The case presented led to a systematic literature review on the effects of hyperbaric oxygen on refractive changes in both HBOT patients and divers. The data were too heterogeneous to make meaningful suggestions on a safety limit to prevent myopisation in diving. [ABSTRACT FROM AUTHOR]

Introduction: Breath-hold divers occasionally surface with signs of fluid accumulation and/or bleeding in air-filled spaces. This constellation of symptoms, recently termed 'freediving induced pulmonary syndrome', is thought to come from immersion pulmonary oedema and/or barotrauma of descent and is colloquially termed a 'squeeze'. There is limited understanding of the causes, diagnosis, management, and return to diving recommendations after a squeeze. Methods: We developed an online survey that queried breath-hold divers on the circumstances and management of individual squeeze events. Results: A total of 132 (94 M, 38 F) breath-hold divers filled out the survey. Most were recreational or competitive freedivers with mean age of 37 years old and nine years of experience. Of those, 129 (98%) held a certification in freediving from an accredited training agency. A total of 103 individuals reported 140 squeeze events from 2008--2023. The average depth at which a squeeze occurred was 43 m. The top contributors to lung squeezes were described as movement at depth, contractions, and inadequate warm-up. The most common symptoms of a squeeze were cough, sputum production, and fatigue. Divers were instructed to wait an average of two months before returning to diving after a squeeze. On average, divers were able to achieve the same depth of their squeeze event three months after the incident. Conclusions: Inadequate warm-up, contractions, and abnormal movement at depth are the most reported causes for a squeeze. Most divers do not seek medical treatment after a lung squeeze event and can return to the same depth within three months. [ABSTRACT FROM AUTHOR]

Purpose: Diving is an intense physical activity under hyperbaric and hyperoxic conditions. The aim of this study is to evaluate the long‐term effects of diving on the thicknesses of retinal layers and retinal anatomy in professional deep and scuba divers. Methods: The study included 52 eyes of deep divers who dive to depths of more than 130 feet (ft), 49 eyes of scuba divers who dive up to 130 ft, and 66 eyes of the control group, consisting of nondiving but regularly exercising males. Measurements of macular retinal layer thicknesses, peripapillary nerve fiber layer thickness, subfoveal choroidal thickness, and peripheral retinal examinations with scleral indentation were performed and statistically compared between the groups. Results: The mean diving duration was 455.00 ± 318.88 h in deep divers and 451.67 ± 281.10 h in scuba divers. The retinal pigment epithelium (RPE) was statistically significantly thicker in deep divers than in scuba divers and the control group on the 3 mm ring of the Early Treatment Diabetic Retinopathy Study grid. Subfoveal choroidal thickness was significantly thicker in deep divers than in scuba divers (p < 0.05). RPE abnormalities showed a significant increase in both the deep and scuba diver groups (p = 0.01). Conclusion: An increased thickening of the subfoveal choroid and RPE, resembling pachychoroid pigment epitheliopathy, was detected in deep divers over a long‐term duration. [ABSTRACT FROM AUTHOR]

Background: Current diving physiology postulates that SCUBA divers' arterial blood gas (ABG) levels vary proportionally to environmental pressure, but, to date, ABGs have only been obtained during simulated dives. Also, recent evidence supports the use of the arterial/alveolar (a:A) partial pressures of oxygen (PO2) ratio to predict the arterial PO2 (PaO2) under hyperbaric conditions from measurements obtained at 1 atmosphere absolute (ATA). This work summarizes ABGs obtained in SCUBA divers in real underwater conditions and aims to validate the a:A ratio in predicting PaO2 in this subset of individuals at depth. Methods: The study was approved by the local ethics committee. After cannulating the radial artery of the non-dominant limb, ABGs were sampled at the surface before the dive (A), at depth (15 meters of freshwater (mfw) or 42 mfw) before (B) and after (C) pedaling on a submersed bicycle for 10 minutes, and back at surface (D). After calculating the surface alveolar PO2 for each subject, the a:A ratio was obtained and used to predict PaO2 at depth. A linear regression between measured and predicted PaO2 was reported, along with the goodness-of-fit F test. Results: Six subjects performed the dive at 15 mfw, and four others at 42 mfw. The PaO2 proportionally increased at both depths, remaining stable before and after pedaling. The a:A calculated from the baseline ABG obtained at rest, out of the water, adequately predicted the PaO2 at depth (R2 = 0.97, p<0.001), better at 15 mfw but losing accuracy at 42 mfw. Conclusions: The ABGs confirmed the proportional rise of PaO2 in SCUBA divers underwater. The a:A ratio could be used to predict the magnitude of PaO2 rise at depth to limit exposure to hyperoxia, especially in repetitive recreational dives and professional divers. [ABSTRACT FROM AUTHOR]

Introduction: Diving in SCUBA modality modifies human physiology in many ways. These modifications have been studied since Paul Bert in a seminal work. This area of research is very sensible to technological development. At now, it is possible to record heart rate (HR) continuously while diving. The study of HR changes in SCUBA diving at different depths in a constant temperature of thermal water is the objective of the present paper. Methods: 18 healthy subjects were enrolled and HR was recorded while SCUBA diving in thermal water at a constant temperature of 33.6∘ C in the deepest Italian pool at Montegrotto (Padova, Italy). Three depths were investigated: −20, −30 and −40 meters. The HR has been recorded with a Galileo SOL diving computer. The dive was subdivided into three phases: descent (DSC), steady on depth (STD), post–dive (RSF), and average HR was evaluated in each phase. Moreover, considering the DSC and STD time duration, a statistical linear regression of HR and relative parameters, intercept and slope, were here assessed. Results: In STD phase, HR slope obtained by regression decreased with depth. A significant difference was found between the slope during STD at −20 vs. −40 m (p ≤ 0.05). Discussion: Present results emphasized different HR physiological adjustments among diving phases. Firstly, during the DSC, a rapid HR decrease is recognized as probably due to a vagal response; secondly, at STD, the inward blood redistribution requires another physiological adjustment. This latter is depth-dependent because of a reduction of cardiac variability. Present data highlight the important cardiac stress need to counteract the diving activity. [ABSTRACT FROM AUTHOR]

Dokdo is an island located in the easternmost part of Korea, which has high levels of biodiversity of birds and fish, especially marine invertebrates. However, the biodiversity of microalgae, especially diatoms (Bacillariophyta), is relatively unknown, despite their ecological importance as primary producers of the marine food web and bioindicators of environmental conditions associated with climate change. To understand the biodiversity of seaweed-associated diatoms from Dokdo, we collected macroalgae present at a depth 5–15 m by SCUBA diving on 17 October 2017. There were a large number of diatoms (over 130 species), even though it was a one-time survey. As it includes too many taxa to cover at once, voucher flora for other taxonomic groups will be provided through the continuous serial papers. This is the first series of seaweed-associated diatoms, with 26 species belonging to the subphyla Melosirophytina and Coscinodisophytina, and the class Mediophyceae. Among these, seven species including one new taxon were reported for the first time in Korea, which, along with the geopolitical characteristics of the survey area, proved that there is no domestic interest in seaweed-related diatoms. In particular, the appearance of species that have been reported in subtropical waters, such as the order Ardissoneales, requires continuous monitoring of marine seaweed-associated diatoms to confirm whether their colonization in Dokdo waters was due to climate change or species-specific water temperature tolerance. [ABSTRACT FROM AUTHOR]

North Sulawesi is renowned for its captivating underwater tourism, attracting SCUBA divers and traditional divers. Given the potential impact of diving activities on lung function, this study aims to explore differences in lung function among self-contained breathing apparatus (SCUBA) diving tourism workers, traditional divers utilizing breathing air compressors and air lines, and non-divers within the coastal areas of tourism destinations in North Sulawesi. Employing a descriptive comparative study with a cross-sectional approach, 90 subjects were categorized into three groups, and selected through simple random sampling. Spirometry was utilized for data collection, and Analysis of Variance (ANOVA) was employed for comparisons, with post hoc analysis for specific differences. The ANOVA analysis revealed significant variations in FVC Predicted, FVC Measured, FEV1, and obstruction and restriction values among SCUBA divers, traditional divers, and non-divers with a level of significance of p < 0.05. Post hoc analysis exhibited noteworthy distinctions in FVC Predicted, FVC Measured, and FEV1 between traditional divers and non-divers, and between SCUBA divers and traditional divers (p < 0.00). Obstruction values showed differences between SCUBA divers and traditional divers (p = 0.012), while restriction values indicated disparities between traditional divers and non-divers (p = 0.019). In conclusion, there were significant variations in lung function among SCUBA diving tourism workers, traditional divers using compressors and air lines, and non-divers within the coastal areas of tourism destinations in North Sulawesi. [ABSTRACT FROM AUTHOR]

Background: Scuba diving was previously excluded because of hypoglycemic risks for patients with type 1 diabetes mellitus(T1DM). Specific eligibility criteria and a safety protocol have been defined, whereas continuous glucose monitoring (CGM) systems have enhanced diabetes management. This study aims to assess the feasibility and accuracy of CGM Dexcom G7 and Free Style Libre 3 in a setting of repetitive scuba diving in T1DM, exploring the possibility of nonadjunctive use. Material and Methods: The study was conducted during an event of Diabete Sommerso® association in 2023. Participants followed a safety protocol, with capillary glucose as reference standard (Beurer GL50Evo). Sensors' accuracy was evaluated through median and mean absolute relative difference (MeARD, MARD) and surveillance error grid (SEG). Data distribution and correlation were estimated by Spearman test and Bland–Altman plots. The ability of sensors to identify hypoglycemia was assessed by contingency tables. Results: Data from 202 dives of 13 patients were collected. The overall MARD was 31% (Dexcom G7) and 14.2% (Free Style Libre 3) and MeARD was 19.7% and 11.6%, respectively. Free Style Libre 3 exhibited better accuracy in normoglycemic and hyperglycemic ranges. SEG analysis showed 82.1% (Dexcom G7) and 97.4% (Free Style Libre 3) data on no-risk zone. Free Style Libre 3 better performed on hypoglycemia identification (diagnostic odds ratio of 254.10 vs. 58.95). Neither of the sensors reached the MARD for nonadjunctive use. Conclusions: The study reveals Free Style Libre 3 superior accuracy compared with Dexcom G7 in a setting of repetitive scuba diving in T1DM, except for hypoglycemic range. Both sensors fail to achieve accuracy for nonadjunctive use. Capillary tests remain crucial for safe dive planning, and sensor data should be interpreted cautiously. We suggest exploring additional factors potentially influencing sensor performance. [ABSTRACT FROM AUTHOR]

SCUBA diving poses risks due to pressure changes during descent (compression) and ascent (decompression). Decompression sickness (DCS) occurs due to gas bubble formation as the pressure decreases, causing joint pain, numbness, dizziness, or even paralysis and death. Immediate treatment involves 100% oxygen to help eliminate inert gases and hyperbaric oxygen therapy (HBOT), which is essential to reduce gas emboli formation and inflammation, thus improving symptoms. We evaluated oxy-inflammation biomarkers in the saliva and urine of nine subjects pre- and post-technical dive on the Haven wreck (GE, Italy). A case of DCS occurred during the dive. The injured diver was treated immediately with O2 and transported to the hyperbaric center of "ASST Ospedale Ca Granda" in Milan. He was treated following the U.S. Navy Treatment Table 5 at 2.8 ATA and the day after with Table 15 at 2.4 ATA. Venous blood and urine samples were collected before and after each HBO treatment. Our study shows that dive increased oxy-inflammation biomarkers (ROS +126%; lipid peroxidation +23%; interleukins-6 +81%, -1β +19%, and TNFα +84%) and nitric oxide metabolites levels (+36%). HBOT after a DCS episode reduced oxidative stress, lowering the very high marker of lipid peroxidation (8-iso-PGF2α), and inhibited inflammatory interleukins. Overall, HBOT improved physiological responses in the diver affected by DCS. [ABSTRACT FROM AUTHOR]

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Purpose: This study aimed to: (1) test and explain the type of experience scuba diving is among people with physical impairments based on the experience-type framework; (2) assess and describe their personality based on the Big Five domains; and (3) identify if personality, years diving, and diving level predict experience-type. Methods: An explanatory sequential mixed methods design was employed. The quantitative phase used a cross-sectional survey (n = 103). The qualitative phase used follow-up interviews with 15 participants divided into 3 case study groups. Joint displays with meta-inferences integrated the data. Results: Quantitative and qualitative findings concurred on scuba being a transformative experience. 82.52% of survey participants reported scuba as a transformative experience, with no significant differences on experience impact based on impairment category (p = 0.56), impairment onset (p = 0.66), gender (p = 0.08), race/ethnicity (p = 0.51), or age (p = 0.07). Big Five personality domains, years diving, or diving level did not predict experience impact (R2 = 0.14, F(12,90) = 1.304, p = 0.2305). Data strand results differed on salient personality domains. Seven qualitative themes emerged, five on experience-type and two on personality. Conclusions: We recommend the exploration of scuba diving as a prospective rehabilitation intervention. IMPLICATIONS FOR REHABILITATION: Innovative rehabilitation interventions that provide positive experiences and long-term health benefits to people with physical impairments are needed. Participants reported that scuba diving had a positive transformative impact in their lives through positive emotions, peace/relaxation, personal growth, development of skills, social connections, physical and mental healing, and lasting behavioral changes. Reporting scuba diving as a transformative experience was not influenced by the scuba divers' personality domains, diving level, demographic characteristics, or the number of years they had been diving. Authors recommend the consideration and further exploration of scuba diving as a prospective physical and psychosocial rehabilitation intervention. [ABSTRACT FROM AUTHOR]

New applications of acceleration measurements are discussed, with a focus on employing microelec-tromechanical system accelerometers for this purpose (due to their outstanding advantages). Some examples of such applications are presented and discussed in the paper. They are mostly related to single- or dual-axis tilt measurements under static or quasi-static conditions. The paper describes and illustrates examples of such measurements in various fields, like scuba diving and freediving or motor-cycle riding, where the application of microelectromechanical system accelerometers is closely related to human safety. The considerations regard both successful commercial implementations and some of the latest patents pending. [ABSTRACT FROM AUTHOR]

In the Southern Atlantic Ocean, asteroids are abundant among the benthic taxonomic groups. The development patterns include a pelagic larva (planktotrophic/lecithotrophic), or a retained larva (internal/oral retention). The main objective was to revise the Asteroidea species composition from the Southern Atlantic (including marine protected areas) and to study their development patterns in relation to environmental conditions. Information was compiled from oceanographic surveys, scuba diving, and the GBIF database. Four species have extended their distribution. The Isla de los Estados island (SIE) and Namuncurá/Burdwood Bank II Marine Protected Area (N MPA II) are separated as independent clusters. SIE would be functioning as a geographical barrier, and N MPA II presents deep sea species. Namuncurá/Burdwood Bank Marine Protected Area (N MPA) presented a majority of protected development species, while in the Beagle Channel, most registered species presented free-planktotrophic larvae. Species with free-planktotrophic larvae and oral brooding strategies are more likely in shallower waters, while internal brooding species occur in deeper waters. Species with free-lecithotrophic larvae are more probable in middle depths, below the euphotic layer. These results are expected to make a valuable contribution to better understanding the general distribution and development patterns of Asteroidea from subantarctic waters, a group of organisms that are top predators of benthic communities. [ABSTRACT FROM AUTHOR]

Breath-hold diving, known also as freediving, is a form of underwater diving in which one holds their breath, making use of no breathing equipment. The complications associated with breath-hold diving have not been well studied in literature, in contrast to scuba diving. Hemoptysis risk is known to be correlated with deep diving. We present here the computed tomography findings of a breath-hold diver who presented with hemoptysis following a dive to 4 meters, which can be considered shallow in the sport. The patient’s chest computed tomography revealed multiple pneumatoceles within the areas of pulmonary hemorrhage. To the best of our knowledge, there have been only a few cases reported to date in which pneumatoceles were identified associated with free diving. [ABSTRACT FROM AUTHOR]

Purpose: Postural control deteriorates following a transition between two environments, highlighting a sensory conflict when returning to natural conditions. Aquatic immersion offers new perspectives for studying postural control adaptation in transitional situations. Our aim is to study immediate and post-task static postural control adaptation on land after a prolonged fin swimming exercise in total immersion. Methods: Standing static postural control was assessed in 14 professional or recreational SCUBA divers (11 men, 3 women; 33.21 ± 10.70 years), with eyes open and closed, before, immediately after, and in the following 20 min following a fully-immersed 45-min fin swimming exercise. Centre-of-pressure metrics (COP) including average position, amplitude, velocity, length and 95% ellipse were evaluated in medial–lateral (x-axis) and anterior–posterior (y-axis) directions with a force platform. The Romberg ratio was also assessed for each metric. Results: A two-way repeated measures analysis of variance revealed a significant effect of the measurement period on COPx vel (p = 0.01), COPy vel (p < 0.01) and Length (p < 0.01), and of the visual condition on COPy vel (p < 0.01) and Length (p < 0.01). Eyes closed measures were systematically higher than eyes open measures despite there being no significant difference in the Romberg ratio in all periods. Post-immersion, the velocity and total trajectory of the centre of pressure remained systematically lower than baseline values in both visual conditions. Conclusion: Post-immersion, COP velocity and length significantly decreased, suggesting a sensory reweighting strategy potentially associated with ankle stiffening. [ABSTRACT FROM AUTHOR]

Marine sports tourism has emerged as a significant niche within the broader tourism industry, offering unique opportunities for economic development, social well-being, and environmental sustainability. This study presents a comprehensive bibliometric analysis of marine sports tourism research, examining publications up to July 2024 from the core collection databases of the Web of Science. The analysis assesses the productivity, research themes, and emerging trends within this field. The results indicate significant growth in research output over the past three decades. Saayman M., Giglio V. J., and Van der Merwe P. are identified as the most productive authors, while Australia, the United States, China, and the United Kingdom demonstrate high levels of research productivity and impact. Ocean & Coastal Management is recognized as the most impactful journal. Keyword co-occurrence and clustering analysis revealed four major research clusters: Environmental Impacts and Community Interaction, Conservation and Ecological Impacts, Behavioral Studies and Perceptions, and Management and Scuba Diving. Topic trend analysis highlights a shift in research focus from the environmental impacts of marine sports tourism to a more integrated approach that considers environmental, economic, and social dimensions. Based on the current research landscape and developmental trajectory, the study proposes future research directions, including addressing identified research gaps, enhancing the resilience of marine sports tourism activities, and developing holistic approaches to sustainable tourism from an interdisciplinary perspective. [ABSTRACT FROM AUTHOR]

This review examines the relationship between the physiological demands of diving and premature ventricular complexes (PVCs) in divers. In the general population, some individuals have a greater tendency to experience PVCs, often without awareness or a clear understanding of the triggering factors. With the increasing availability and popularity of both scuba and apnoea diving, more people, including those with a predisposition to PVCs, are engaging in these activities. The underwater environment, with its unique stressors, may increase the risk of arrhythmogenic events, particularly PVCs. Here, we review the prevalence, pathophysiology, and aggravating factors of PVCs in divers, emphasising the need for a comprehensive cardiovascular assessment. Evidence suggests a higher prevalence of PVCs in divers compared with the general population, influenced by factors such as age, dive depth, gas bubbles, cold water immersion, pre-existing cardiovascular diseases, and lifestyle factors. The change in environment during diving could potentially trigger an increased frequency of PVCs, especially in individuals with a pre-existing tendency. We discuss diagnostic strategies, management approaches, and preventive measures for divers with PVCs, noting that although guidelines for athletes can be adapted, individual assessment is crucial. Significant knowledge gaps are identified, highlighting the need for future research to develop evidence-based guidelines and understand the long-term significance of PVCs in divers. This work aims to evaluate potential contributing factors to PVCs in divers and identify individuals who may be at higher risk of experiencing major adverse cardiovascular events (MACEs). This work aims to improve diver safety by promoting collaboration between cardiologists and diving medicine specialists and by identifying key areas for future investigation in this field. This work aims to improve the safety and well-being of divers by understanding the cardiovascular challenges they face, including pressure changes, cold water immersion, and hypoxia. We seek to elucidate the relationship between these challenges and the occurrence of PVCs. By synthesising current evidence, identifying knowledge gaps, and proposing preliminary recommendations, we aim to encourage collaboration between cardiologists and diving medicine specialists to optimise the screening, management, and risk stratification of PVCs in the diving population. [ABSTRACT FROM AUTHOR]

The incidence of diving accidents is increasing. Point-of-care ultrasound is the only imaging tool available in the field for the military physician who practices in isolated conditions. While ultrasound is integrated in the pre-hospital evaluation protocols of severe trauma patients, few applications are described for diving accident victims. Through a clinical case, we propose an algorithm of ultrasound triage for diving accidents with pulmonary symptoms. Point-of-care ultrasound makes it possible to avoid a risky transfer, by supporting a diagnosis and the treatment on the spot, to rule out contraindications to recompression, and to detect and monitor the treatment of high-risk complications such as the capillary leak syndrome. [ABSTRACT FROM AUTHOR]

The safety of SCUBA divers remains at high risk in deep-sea owing to multiple factors such as dangerous surrounding, rely upon technical equipment necessary for life support, decreased underwater navigation, and communication infrastructure. Gradual decrease and increase in water temperature and pressure corresponding to depth are among the most common problems that cause most of the fatalities in deep-sea diving. Therefore, different gadgets for accurate measurement of vital parameters, reliable navigation, and seamless communication are of prime importance. In this paper, we propose an all-optical technique for local and remote monitoring of underwater temperature and pressure for deep-sea SCUBA divers based on fiber Bragg grating (FBG) sensors and underwater optical communication-single mode fiber (UWOCSMF) integrated transmission system. The proposed technique is implemented using two FBG temperature and pressure sensors fixed over diver's suit and UWOC-SMF integrated transmission system for simultaneous local and remote monitoring of underwater temperature and pressure. Remote monitoring of underwater temperature and pressure is achieved at ship station through a remotely operated underwater vehicle (ROV) and UWOC-SMF integrated transmission system by means of shifts in the original Bragg wavelengths of sensors due to temperature and pressure variations. The performance of the sensors is analyzed for pressure and temperature in the range of 0 to 6.4 MPa (≈0 to 655mH2O) and 40 to -2°C, respectively corresponding to different depths. The results show that the proposed technique can work well in the deep ocean over a range of pressures and temperatures of 0-7 MPa and 40 to -2°C while achieving a temperature sensitivity of 4.3 p.m./°C and a pressure sensitivity of 30.5 p.m./MPa. Clear spectra of reflected signals from FBG sensors at ship station are achieved after signal transmission over UWOC-SMF hybrid link. [ABSTRACT FROM AUTHOR]

A transient female passenger in her 40s presented to the emergency department (ED) exhibiting drowsiness post-scuba diving. Despite normal initial vitals, she reported dizziness, sleepiness, and occipital headache. A computed tomography (CT) scan showed a severe posterior circulation acute infarction affecting various brain regions, resulting in significant mass effects and complications like 4th ventricle compression, cerebellar tonsillar herniation, and hydrocephalus. Extensive diagnostic tests, blood workup, and stroke evaluations revealed normal findings, except for an incidental patent foramen ovale (PFO). Collaboration with neurosurgery led to her transfer for life-saving extraventricular drain (EVD) insertion and posterior fossa decompression. Treatment included right-side EVD insertion, suboccipital craniectomy, and foramen magnum decompression. Postoperatively, she was extubated the next day, alert, without focal neurological deficits. Upon EVD removal, a repeat CT head scan showed regression of mass effect. She was discharged home safely after 16 days, fully ambulating. [ABSTRACT FROM AUTHOR]

Simple Summary: Simple Summary: This research details the discovery of three new myzostomid worm species from feather stars near Sanya, Hainan Island. Additionally, we report the presence of Myzostoma polycyclus in the South China Sea for the first time. These findings, combined with an analysis of available molecular data, underscore significant gaps in our understanding of marine biodiversity of myzostomids. This research delves into the molecular and morphological characteristics of myzostomid worms associated with common shallow-water feather stars (Echinodermata: Crinoidea: Comatulidae) in the coastal waters near Sanya, Hainan Island. Through the examination of specimens collected at depths of up to 10 m using scuba diving techniques, we describe three new species (Myzostoma ordinatum sp. nov., M. scopus sp. nov., and M. solare sp. nov.) and report the first record of Myzostoma polycyclus Atkins, 1927 in the South China Sea. The absence of overlap with the seven previously documented Myzostomida species in the shallow waters of Hong Kong and Shenzhen reveals significant gaps in our understanding of marine biodiversity in the South China Sea. These findings, combined with an analysis of available molecular data, underscore the potential existence of unexplored and diverse symbiotic relationships among marine invertebrates within the region. [ABSTRACT FROM AUTHOR]

Radon (222Rn) is a widely used tracer in groundwater and surface water studies. In some applications of radon, samples need to be collected from deep submerged areas or discharge points such as caves or springs, locations typically accessed by scuba diving. However, there are no established sampling methods for collecting water by scuba diving for Rn analysis. We assessed four underwater sample collection methods: (a) injection into a catheter bag followed by transfer to a bottle after the dive, (b) air purging and then filling of a bottle by allowing gas to escape, (c) air purging followed by gas escape, and then overfilling of water with a syringe, and (d) collection with a syringe followed by transfer to a bottle. The samples were collected from the anchialine caves of the Yucatan Peninsula which are the longest underwater cave systems. The samples were analyzed using the same Rn‐in‐air analyzer and protocols. Statistical comparison of sampling at the same location with different methods showed no significant differences in Rn activity. No collection method is superior in terms of measurement quality; operational simplicity is thus preferred. Statistically significant differences in activity were observed between fresh and saline samples from the same cave, with higher activities in the fresh samples, regardless of sampling method. The saline groundwater therefore has a lower residence time, suggesting vigorous landwards flow. Our assessment shows that in situ sampling of discrete water samples for Rn tracing by divers is a useful and powerful approach allowing the study of otherwise impossible sites. Key Points: Different underwater sample collection methods by scuba divers for Rn‐in‐water was assessedAll four tested methods showed no differences in measured Rn activityRadon is higher in saline groundwater versus fresh water in anchialine submerged caves of the Yucatan Peninsula [ABSTRACT FROM AUTHOR]

The Atlantic pearl oyster, Pinctada radiata (Leach, 1814), is an Indo-Pacific bivalve of the subtidal zone that has colonized habitats all over the Mediterranean. There is a lack of detailed information on the reproductive activity of P. radiata in Hellenic waters, especially following the recent amendment of national legislation aiming to regulate the fishery and prevent illegal fishing and trafficking as a substitute for indigenous oysters. A total of 703 individuals were collected by scuba diving from the southwest part of Evia Island. Gonad microscopic examination indicated that gametogenesis occurs from February to September, with a recovery stage in early autumn. Synchronicity occurs for both sexes, with temperature being the main controlling factor. The annual recruitment pattern indicated two prominent peaks of similar magnitude. Analysis of covariance indicated a significant temperature effect on gonad index above 22 degrees. Onset of sexual maturity (L50) was estimated at 47.2 mm in shell height and 27.09 gr in total weight for the entire population. The sex ratio was in favor of females at 1:1.70, with 7% and 19% of the individuals assessed macroscopically and microscopically identified as hermaphrodites, respectively. Results offer valuable information for the management and conservation of pearl oyster populations. [ABSTRACT FROM AUTHOR]

Background Decompression sickness (DCS) is a well-known risk associated with scuba diving, particularly in people with right-to-left shunt, such as patent foramen oval (PFO). Herein, we present a unique case of late PFO permeabilization after closure. Case summary A 26-year-old male diver was diagnosed with DCS following a dive at 36 m. He underwent PFO closure with a STARFLEX® prosthesis. Ten years later, the patient was presented with recurrent manifestations suggestive of DCS. The performed diagnostic work-up detects a permeabilization of the implanted prosthesis, and he was treated with a conservative approach. Discussion This case highlights the challenges in the management of PFO in divers and raises concerns about the long-term efficiency of PFO closure and the impact of diving-related factors on prosthesis patency. [ABSTRACT FROM AUTHOR]

Background Scuba diving is an increasingly popular activity that involves the use of specialized equipment and compressed air to breathe underwater. Scuba divers are subject to the physiological consequences of being immersed in a high-pressure environment, including, but not limited to, increased work of breathing and kinetic energy expenditure, decreased fluid absorption, and alteration of metabolism. Individual response to these environmental stressors may result in a differential risk of decompression sickness, a condition thought to result from excess nitrogen bubbles forming in a diver’s tissues. While the mechanisms of decompression sickness are still largely unknown, it has been postulated that this response may further be influenced by the diver’s health status. Nutritional intake has direct relevancy to inflammation status and oxidative stress resistance, both of which have been associated with increased decompression stress. While nutritional recommendations have been determined for saturation divers, these recommendations are likely overly robust for recreational divers, considering that the differences in time spent under pressure and the maximum depth could result nonequivalent energetic demands. Specific recommendations for recreational divers remain largely undefined.Methods This narrative review will summarize existing nutritional recommendations and their justification for recreational divers, as well as identify gaps in research regarding connections between nutritional intake and the health and safety of divers.Results Following recommendations made by the Institute of Medicine and the Naval Medical Research Institute of Bethesda, recreational divers are advised to consume ~170–210 kJ·kg−1 (40–50 kcal·kg−1) body mass, depending on their workload underwater, in a day consisting of 3 hours’ worth of diving above 46 msw. Recommendations for macronutrient distribution for divers are to derive 50% of joules from carbohydrates and less than 30% of joules from fat. Protein consumption is recommended to reach a minimum of 1 g of protein·kg−1 of body mass a day to mitigate loss of appetite while meeting energetic requirements. All divers should take special care to hydrate themselves with an absolute minimum of 500 ml of fluid per hour for any dive longer than 3 hours, with more recent studies finding 0.69 liters of water two hours prior to diving is most effective to minimize bubble loads. While there is evidence that specialized diets may have specific applications in commercial or military diving, they are not advisable for the general recreational diving population considering the often extreme nature of these diets, and the lack of research on their effectiveness on a recreational diving population.Conclusions Established recommendations do not account for changes in temperature, scuba equipment, depth, dive time, work of breathing, breathing gas mix, or individual variation in metabolism. Individual recommendations may be more accurate when accounting for basal metabolic rate and physical activity outside of diving. However, more research is needed to validate these estimates against variation in dive profile and diver demographics.

Isla Natividad is a small fishing community off the Pacific coast of Baja California Sur, México. A lease from the Mexican government allows them exclusive rights over the waters surrounding their island. They are part of a successful fishing cooperative, la Sociedad Cooperativa de Producción Pesquera Buzos y Pescadores that sells their seafood on the international market. Isla Natividad is an island of fishermen. Like many small fishing communities worldwide, Isla Natividad is concerned with climate change, diminishing fish populations, and the increased effort required to get their product to market. They also worry about their children's futures on an island with few work opportunities. Isla Natividad is part of a federally protected area, la Reserva de la Biosfera el Vizcaino, so the town's footprint cannot expand, and the number of residents is limited to around 400. As members retire, they must leave the island and return to the mainland. If the children of current members are not interested in working in the fishing industry, they must pursue employment elsewhere.A small group was formed to bring ecotourism to the island. Through interviews with community members, this film explores the island's desire to open up to new avenues of employment while giving voice to its fears of losing its identity. Isla Natividad allows the residents of the island to tell their own story.Please see the film attached to this project here: https://drive.google.com/file/d/1QylfFaZoZ1KnO1FTGwItCwnyiA-LZTx5/view

Indonesia's diving tourism ranks second among the World's Best Diving Destinations, according to Scuba Diving magazine readers' choices in 2019. Weh Island, in particular, is noted for its significant potential in diving tourism. This study aims to empirically evaluate the impact of attraction, facilities, and accessibility on diving interest at Weh Island. The research targeted individuals with diving certifications, using purposive sampling to gather responses from 97 participants. A quantitative approach was employed, utilizing SmartPLS software for analysis. The results indicate that attraction has a direct positive effect on diving interest, with a significance value of 0.001 (<0.05), suggesting that an increase in attraction leads to a 42.4% rise in visiting interest. Similarly, facilities also have a direct positive effect on diving interest, with a significance value of 0.000 (<0.05), implying that improved facilities result in a 35.3% increase in visiting interest. The implications of this study highlight the important role of attractions and facilities in increasing diving interest. This implies that improving these factors can significantly increase tourist interest in Weh Island. Stakeholders in the dive tourism sector should focus on improving attractions and facilities to increase this potential and attract more divers. Further research could explore the impact of accessibility and other factors on dive tourism to provide a more comprehensive understanding of tourist interest. [ABSTRACT FROM AUTHOR]

Introduction: Recreational scuba diving, a popular adventure sport, inherent risks such as high-pressure environments, and physical/challenges, potentially leading to injuries or illnesses. This study aimed to determine the prevalence of diving-related issues among recreational scuba divers in Malaysia and identify associated factors. The findings inform preventive measures for stakeholders, including dive operators, instructors, and regulatory bodies. Materials and methods: A cross-sectional study was conducted at diving centres located in the East Coast of Peninsular Malaysia, specifically in Perhentian and Tioman Islands. Data collection involved using a standardized proforma checklist, and the analysis was carried out using SPSS version 26. Descriptive analysis, as well as simple and multiple logistic regression, were employed to analyze the data. Results: Out of 407 scuba divers, 145 (36.1%) reported diving-related injuries or illnesses. The most common conditions were barotrauma (17.9%), muscle cramps (14.0%), and panic attacks (10.1%). Divers with injuries or illnesses were predominantly male, Malaysian, open water certification holder, used personal gear, and with mean age 31.13 (SD=6.23). Level of diving certificate was significantly associated with diving-related injury/illness according to multiple logistic regression, with adjusted odds ratio of 3.78 (95% CI: 1.68, 8.49; p < 0.05). Conclusion: This study underscores the imperative of enhancing diver safety and emphasizes the vital need to improve safety in Malaysian recreational scuba diving. The observed association between lower certifications and injuries underscores the importance of targeted preventive measures for stakeholders, contributing to overall advancements in diving safety protocols in Malaysia. [ABSTRACT FROM AUTHOR]

To the best of our knowledge, this study is the first to track and demonstrate the mortality event in Diadema setosum (Leske, 1778) along the Egyptian Red Sea coasts. The diadematid is a group of echinoid echinodermates that play an important ecological role in marine ecosystems. However, the current global mass mortality events in Diadema setosum have the potential to significantly change the fundamental structure of the ecosystem. This report was based on the 2023-summer observations of a D. setosum die-off during an ecological investigation in the northern Red Sea, Egypt. To determine the entirety of the event, a group from the Red Sea protectorates carried out an extensive survey simultaneously. The current survey covered the coastal regions of the Elba protectorate in the south, the Wadi El Gemal protected area in the middle, and Hurghada in the north. A diverse population of D. setosum was found dead on the bottom during both snorkeling and scuba diving. Representative photographs were taken at each explored site. Several features were noticed in the dead D. setosum, including a frail body, sand-covered body parts, spines distributed on the bottom, and inactive tube feet. The current findings, therefore, recommend crucially the performance of regular monitoring for the status of D. setosum. In addition, biological and ecological investigations are needed as soon as possible to interpret the causative and potential factors responsible for D. setosum loss. [ABSTRACT FROM AUTHOR]

Anoplodactylus arescus du Bois-Reymond Marcus, 1959, was first recorded and described from the northern Red Sea. New material was collected from soft bottom substrates spanning Hurghada to Halayeb from 2019 to 2020. The collection sites varied in depth, ranging from intertidal to 35 meters deep. The intertidal sand samples were manually collected during snorkeling, while the deep samples required SCUBA diving for collection. Pycnogonid fauna were isolated, sorted, counted, and then identified to the lowest taxonomic level. The results revealed Anoplodactylus arescus as abundant species among the seven study areas selected. Grain size analysis was conducted at each site to evaluate its effect on the pycnogonid distribution. A list of species of pycnogonids reported from the Red Sea was provided based on our collection and approved literature. The results revealed a diverse community of pycnogonids in the Red Sea, with 17 species identified, belonging to nine genera and eight families. The study further indicates that coarse and medium sand, ranging from 125- 500µm, provides a suitable substrate for Anoplodactylus arescus. Pycnogonids were found in lower densities out of this grain size range. [ABSTRACT FROM AUTHOR]

A blood component analysis is an early step for evaluating inflammatory disorders, but it can be unfeasible in some settings. This pilot study assessed whether extracellular vesicle (EV) changes in perspiration are parallel to those occurring in blood as an alternative or complementary option to diagnose an inflammatory response. In parallel studies, EVs were analyzed in perspiration and blood obtained before and after five self-contained underwater breathing apparatus (SCUBA) divers at the National Aquarium in Baltimore performed a dive to 3.98 m of sea water for 40 min, and five non-divers performed an exercise routine at ambient atmospheric pressure. The results demonstrated that microparticles (MPs) are present in perspiration, their numbers increase in the blood in response to SCUBA diving, and the interleukin (IL)-1β content increases. In contrast, while blood-borne MPs became elevated in response to terrestrial exercise, no statistically significant increases occurred in perspiration, and there were no changes in IL-1β. There were no statistically significant elevations in the exosomes in perspiration or blood in response to SCUBA diving and few changes following terrestrial exercise. These findings suggest that an MP perspiration analysis could be a non-invasive method for detecting inflammatory responses that can occur due to the oxidative stress associated with SCUBA diving. [ABSTRACT FROM AUTHOR]