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Purpose: Diving in warm water increases thermal risk during exercise compared to thermoneutral waters. The purpose of this study was to evaluate exercise endurance in warm- and hot-water conditions in divers habituated to wet or dry heat., Methods: Nineteen male divers completed this study at the Navy Experimental Diving Unit. Subjects were assigned DRY or WET heat habituation groups. The DRY group (n=9) cycled at 125-150W for one hour in a non-immersed condition (34.4˚C, 50%RH), while the WET group (n=10) cycled at 50W for one hour while immersed in 34.4˚C water. Exercise time to exhaustion was tested on an underwater cycle ergometer in 35.8˚C (WARM) and 37.2˚C (HOT) water at 50W. Core temperature (Tc) was continuously recorded and for all dives., Results: Time to exhaustion was reduced in HOT compared to WARM water (p ≺0.01) in both DRY (92.7 ± 41.6 minutes in 35.8°C vs. 43.4 ± 17.5 minutes in 37.2°C) and WET (95.9 ± 39.2 minutes in 35.8°C vs. 53.4 ± 27.5 minutes in 37.2°C) groups, but did not differ between groups (p=0.62). Rate of Tc rise was greater with higher water temperature (p ≺0.01), but was not different between groups (p=0.68). Maximum Tc (p=0.94 and p=0.95) and Tc change from baseline (p=0.38 and p=0.34) was not different between water temperatures or habituation group, respectively., Conclusion: Endurance decreased with increased water temperature but was not different between WET and DRY. Divers became exhausted at a similar core temperature during WARM- and HOT-water exercise. Mechanisms and applications of heat acclimation for warm-water diving should be further explored., Competing Interests: The authors of this paper declare no conflicts of interest exist with this submission., (Copyright© Undersea and Hyperbaric Medical Society.)

Drowning is a leading cause of fatality among children in the United States, and pool/spa aquatic structures represent common locations of submersion incidents. This study employed narrative case review to understand characteristics related to permission, supervision, and precipitating events in childhood submersion incidents. Retroactive analysis of 1537 fatal and non-fatal submersion incidents among children age 13 years old and younger was conducted using the U.S. Consumer Products Safety Commission In-Depth Investigations dataset from 2000-2017. Narrative descriptions were coded according to the themes of permission, supervision, and precipitating events. In most (86%) incidents, the child did not have permitted water access, and 80% of narratives indicated the child was alone at time of incident. These attributes were significantly associated with a fatal outcome (No permission: OR 11.98, 95% CI 7.97-18.06; Alone: OR 34.93, 95% CI 19.69-61.96). The average length of inactive supervision time was 15.6 min; this duration significantly differed by non-fatal (3.2 min) and fatal (16.1 min) outcomes ( p < 0.001). More than half of cases occurred under the supervision type of a parent (56%), followed by grandparents (14%) and childcare provider (10%). Submersion incidents with a non-parent supervisor were two times more likely to result in a fatal outcome (OR 1.87, 95% CI 1.07-3.64). The most frequently occurring precipitating events included outdoor play (46%), a social gathering (36%), and previous water play (15%). Narrative excerpts further illustrate how tragic submersion events can unfold quickly and unpredictably. Education campaigns should target all adults that supervise children and reiterate key findings in that many submersion incidents occur (1) without permitted pool use, (2) without active supervision, and (3) when a caregiver is distracted. Multiple strategies should be utilized to add layers of projection against submersion injury.

Blow-fly (Diptera: Calliphoridae) immatures are the main colonizers of decomposing remains, and any information on what influences their growth and development are important to forensic entomologists when they are required to estimate post-mortem intervals during a death investigation. Much of this work has been qualified and quantified in terrestrial environments, but is deplete in aquatic environments. When considering a blow-fly's life history, the longest immature life stage goes from the formation of the puparium to adult emergence, and involves metamorphosis. In an aquatic scenario a corpse may be completely submerged, floating on the surface and or it could be associated with water but neither submerged or floating (e.g. beached on a seashore or washed up after a flood event). The present study concerns two blow-fly species, Lucilia sericata (Meigen) and Calliphora vomitoria (L.), and the effects of the age of the intra-puparial forms ("pupal age") and resultant survival, when submerged in tap, river or salt water for varying times - up to 3 days. The experiment was conducted in two localities, L. sericata in Boston USA and C. vomitoria in Turin, Italy, and full puparia of both species were divided into 4 age cohorts ("white", "young", "medium", and "old') before submergence. L. sericata intra-puparial forms showed a three time greater survival rate compared to C. vomitoria intra-puparial forms when submerged in each of the three water types. Both species had the highest survival rate in tap water. Overall, younger and older intra-puparial forms showed a greater and significant survival rate than medium intra-puparial forms when submerged. The eclosion time following submersion of C. vomitoria and L. sericata was mainly influenced by both the age at which the intra-puparial forms were submerged, and by the type of water, but the duration of the submersion also influenced the eclosion time of L. sericata. These results are discussed considering blow-fly physiology. A deeper understanding of the dynamics of survival and growth rate of blow-fly intra-puparial forms on human remains that have undergone a period of submergence could assist in the estimation of the time of death in criminal cases connected to different aquatic environments., (Copyright © 2020. Published by Elsevier B.V.)

Introduction: Submersion injury or drowning is a leading preventable cause of pediatric mortality and morbidity. Submersion injuries are often accompanied by hypothermia and asphyxia that can lead to inadequate oxygen delivery to tissues and subsequent cardiac arrhythmias., Methods: This simulation-based curriculum involves the identification and management of a submersion injury in a 4-year-old boy who was rescued from a cold-water submersion. The simulated patient is apneic, pulseless, bradycardic, and hypothermic; he is being bag-mask ventilated on arrival without intravenous access. He ultimately develops ventricular fibrillation. Providers must recognize the degree of submersion injury, initiate early airway protection, adequately address circulation, and be alert to developing hypothermia and cardiac arrhythmias to prevent further decompensation. This scenario can be modified based on trainee level (pediatric residents vs. pediatric emergency medicine fellows)., Results: A total of 22 trainees (PGY 1-PGY 6 pediatric residents and pediatric emergency medicine fellows) participated in this simulation curriculum on separate occasions and rated it as an overall positive learning experience. The curriculum's goal is to provide learners with an opportunity to manage life-threatening pediatric submersion injuries, where the correct steps need to be taken in a limited period of time., Discussion: We have provided preparatory materials to help instructors set up, run, and debrief the scenario in a standardized fashion. The debriefing tools allow for adaptation depending on learners' needs and individual experiences during the simulated scenario. Also included are supporting educational materials and a learner feedback form that can be used to evaluate the session., Competing Interests: None to report.

This case study reports on DNA analysis from different skeletal elements of an individual recovered 2 years after going missing in the English Channel. Selected bones were also re-submerged for an additional 2 years and re-analysed. By comparing results from both time points, this study concludes that high-load-bearing bones, particularly the bones of the feet, appear to be a preferable source of DNA for identification of skeletal tissue recovered from similar conditions., (Copyright © 2013 Elsevier Ltd and Faculty of Forensic and Legal Medicine. All rights reserved.)

Drowning is the third leading cause of death from unintentional injury worldwide, accounting for 7% of all injury-related deaths. The World Health Organization estimates that there are ≈236 000 deaths due to drowning worldwide each year. Significant efforts have focused on creating systems to prevent drowning, but an average of 4000 fatal and 8000 nonfatal drownings still occur annually in the United States—likely an underestimate. Drowning generally progresses from initial respiratory arrest due to submersion-related hypoxia to cardiac arrest; thus, it can be challenging to distinguish respiratory arrest from cardiac arrest because pulses are difficult to accurately palpate within the recommended 10-second window. Therefore, resuscitation from cardiac arrest attributable to this specific circumstance must focus on restoring breathing as much as it does circulation. Resuscitation from drowning may begin with in-water rescue breathing when safely provided by rescuers trained in the technique and should continue with chest compressions, in keeping with basic life support guidelines, once the drowned individual and the rescuer are in a safe environment (eg, dry land, a boat). This focused update incorporates systematic reviews from 2021 to 2023 performed by the International Liaison Committee on Resuscitation related to the resuscitation of drowning. These clinical guidelines are the product of a committee of experts representing the American Heart Association and the American Academy of Pediatrics. The writing group reviewed the recent International Liaison Committee on Resuscitation systematic reviews, including updated literature searches, prior guidelines related to resuscitation from cardiac arrest following drowning, and other drowning-related publications from the American Heart Association and American Academy of Pediatrics. The writing group used these reviews to update its recommendations aimed at resuscitation of cardiac arrest following drowning in adults and children. [ABSTRACT FROM AUTHOR]

Aim. Bimodal education in the context of bilingual education has a positive impact on the communication and broader cognitive development of the hearing impaired child. Concepts discussed. This article discusses the method of bilingual education in the context of its use in the education of children with hearing impairment. In this area, special attention is paid to Bilingual Education popularised in Poland by Magdalena Dunaj. Conclusions. Bilingual education of Deaf children supports the communicative and cognitive development of children with hearing impairment. However, it requires a lot of work on the part of both the parents and the child, as well as extensive support from health services and educational institutions. Cognitive value. The described educational model is optimal for the development of children with hearing impairment and should be popularised. Furthermore, bilingualism for hearing impaired children is not a frequently addressed topic in pedagogy. [ABSTRACT FROM AUTHOR]

This article seeks to locate Pakistan’s middle-tier English-medium private schools in the global educational discourse on immersion and submersion. Using qualitative and quantitative data from a case study conducted in Karachi, it highlights the effects of English-medium education on native speakers of the national language, Urdu, among the new middle class. The study findings illustrate the immersive nature of schooling and the importance placed on the English language by key stakeholders, such as administrators, English teachers, and parents, so much so that the majority of surveyed students prefer to do their pleasure reading in English instead of their high-status home language, Urdu. This heritage loss, acutely expressed by Urdu teachers in particular, shows that the students’ initial additive learning experience becomes subtractive due to the extended, unabated exposure to schooling in the English language and the increasing incorporation of English at home by Urdu-speaking parents at the behest of school officials. This research is important because earlier studies have focused on ‘Urdu imperialism’ over the minoritized regional languages in government or low-fee private schools whereas this study demonstrates the erosion of Urdu, the lingua franca across Pakistan, among the new middle class in the face of English’s linguistic imperialism. [ABSTRACT FROM AUTHOR]

Drowning is a frequent cause of accidental deaths and injuries, resulting in a significant but preventable global health problem. It is characterized by respiratory impairment due to submersion of the airway, or immersion of the body including the airway, leading to global hypoxic injury. Risk factors for drowning include inadequate supervision of children, recreational or occupational access to water, risk-taking behaviour and underlying medical conditions. Management priorities include rescue and basic life support, with an emphasis on rescue breaths and reversal of hypoxia. Supportive critical care is directed towards optimizing oxygenation and circulation, and preventing complications. Temperature control is important, as hypothermia complicates drowning and may limit the efficacy of resuscitative attempts when severe. Survival rates after cardiac arrest due to drowning are poor, and patients who are unconscious on admission to hospital have a guarded prognosis. Public health initiatives are important to prevent drowning. [ABSTRACT FROM AUTHOR]

As a result of recent immigration, Germany has become a multilingual country with a great need for multilingual education. In the first part of the article the roles of minority and immigrant languages in Germany are discussed. Some demographic changes are briefly outlined as well as the implications for the general education system. In the second part, submersion and immersion approaches are discussed and evaluated in the context of the German school system. It is argued that classroom interactional competence is a crucial factor in promoting students‘ linguistic skills. [ABSTRACT FROM AUTHOR]

Local normal form theorems for smooth equivariant maps between infinite-dimensional manifolds are established. These normal form results are new even in finite dimensions. The proof is inspired by the Lyapunov–Schmidt reduction for dynamical systems and by the Kuranishi method for moduli spaces. It uses a slice theorem for Fréchet manifolds as the main technical tool. As a consequence, the abstract moduli space obtained by factorizing a level set of the equivariant map with respect to the group action carries the structure of a Kuranishi space, i.e., such moduli spaces are locally modeled on the quotient by a compact group of the zero set of a smooth map. The general results are applied to the moduli space of anti-self-dual instantons, the Seiberg–Witten moduli space and the moduli space of pseudoholomorphic curves. [ABSTRACT FROM AUTHOR]

Drowning is "the process of experiencing respiratory impairment from submersion or immersion in liquid." According to the World Health Organization, drowning claims the lives of > 40 people every hour of every day. Drowning involves some physiological principles and medical interventions that are unique. It occurs in a deceptively hostile environment that involves an underestimation of the dangers or an overestimation of water competency. It has been estimated that > 90% of drownings are preventable. When water is aspirated into the airways, coughing is the initial reflex response. The acute lung injury alters the exchange of oxygen in different proportions. The combined effects of fluid in the lungs, loss of surfactant, and increased capillary-alveolar permeability result in decreased lung compliance, increased right-to-left shunting in the lungs, atelectasis, and alveolitis, a noncardiogenic pulmonary edema. Salt and fresh water aspirations cause similar pathology. If the person is not rescued, aspiration continues, and hypoxemia leads to loss of consciousness and apnea in seconds to minutes. As a consequence, hypoxic cardiac arrest occurs. The decision to admit to an ICU should consider the patient's drowning severity and comorbid or premorbid conditions. Ventilation therapy should achieve an intrapulmonary shunt ≤ 20% or Pao2:Fio2 ≥ 250. Premature ventilatory weaning may cause the return of pulmonary edema with the need for re-intubation and an anticipation of prolonged hospital stays and further morbidity. This review includes all the essential steps from the first call to action until the best practice at the prehospital, ED, and hospitalization. [ABSTRACT FROM AUTHOR]

Endowing differentiable functions from a compact manifold to a Lie group with the pointwise group operations one obtains the so-called current groups and, as a special case, loop groups. These are prime examples of infinite-dimensional Lie groups modelled on locally convex spaces. In the present paper, we generalise this construction and show that differentiable mappings on a compact manifold (possibly with boundary) with values in a Lie groupoid form infinite-dimensional Lie groupoids which we call current groupoids. We then study basic differential geometry and Lie theory for these Lie groupoids of mappings. In particular, we show that certain Lie groupoid properties, like being a proper étale Lie groupoid, are inherited by the current groupoid. Furthermore, we identify the Lie algebroid of a current groupoid as a current algebroid (analogous to the current Lie algebra associated to a current Lie group). To establish these results, we study superposition operators Cℓ(K, f): Cℓ (K,M) → Cℓ (K,N), γ → f o γ between manifolds of Cℓ-functions. Under natural hypotheses, Cℓ(K, f) turns out to be a submersion (an immersion, an embedding, proper, resp., a local diffeomorphism) if so is the underlying map f : M → N. These results are new in their generality and of independent interest. [ABSTRACT FROM AUTHOR]

Drowning is a frequent cause of accidental deaths and injuries, resulting in a significant but preventable global health problem. It is characterized by respiratory impairment due to submersion of the airway, or immersion of the body including the airway, leading to global hypoxic injury. Risk factors for drowning include inadequate supervision of children, recreational or occupational access to water, risk-taking behaviour and underlying medical conditions. Management priorities include rescue and basic life support, with an emphasis on rescue breaths and reversal of hypoxia. Supportive critical care is directed towards optimizing oxygenation and circulation, and preventing complications. Temperature control is important, as hypothermia complicates drowning and may limit the efficacy of resuscitative attempts when severe. Survival rates after cardiac arrest due to drowning are poor, and patients who are unconscious on admission to hospital have a guarded prognosis. Public health initiatives are important to prevent drowning. [ABSTRACT FROM AUTHOR]

The Wilderness Medical Society convened a panel to review available evidence supporting practices for the prevention and acute management of drowning in out-of-hospital and emergency medical care settings. Literature about definition and terminology, epidemiology, rescue, resuscitation, acute clinical management, disposition, and drowning prevention was reviewed. The panel graded evidence supporting practices according to the American College of Chest Physicians criteria, then made recommendations based on that evidence. Recommendations were based on the panel's collective clinical experience and judgment when published evidence was lacking. [ABSTRACT FROM AUTHOR]

Drowning is a frequent cause of accidental deaths and injuries, resulting in a significant but preventable global health problem. It is characterized by respiratory impairment due to submersion of the airway, or immersion of the body including the airway, leading to global hypoxic injury. Risk factors for drowning include inadequate supervision of children, recreational or occupational access to water, risk-taking behaviour and underlying medical conditions. Management priorities include rescue and basic life support, with an emphasis on rescue breaths and reversal of hypoxia. Compression-only cardiopulmonary resuscitation is not recommended in drowning victims. Supportive critical care is directed towards optimizing oxygenation and circulation, and preventing complications. Temperature control is important, as hypothermia complicates drowning and may limit the efficacy of resuscitative attempts when severe. Survival rates after cardiac arrest due to drowning are poor, and patients who are unconscious on admission to hospital have a guarded prognosis. Consequently public health initiatives to prevent drowning are important. [ABSTRACT FROM AUTHOR]

Drowning is a process resulting in primary respiratory impairment from submersion/immersion in a liquid medium. It is a frequent cause of unintentional injury deaths and public health initiatives to prevent drowning are important as there are no specific interventions proven to improve outcomes in drowning victims. Risk factors for drowning include inadequate supervision, recreational or occupational access to water, risk-taking behaviour and underlying medical conditions. Pathophysiological events in the process of drowning are secondary to hypoxaemia that results from the immersion injury. The major determinant of outcome after drowning is the degree of hypoxic neurological insult and subsequent recovery. Management priorities in the drowning victim include rescue from the water and basic life support with an emphasis on rescue breaths. Compression-only cardiopulmonary resuscitation is not recommended in drowning victims. Supportive critical care is directed towards optimizing oxygenation and circulation, and preventing complications. Temperature control is important as hypothermia complicates drowning and may limit the efficacy of resuscitative attempts when severe. Therapeutic hypothermia may be considered in the treatment of unconscious survivors of drowning. Survival rates after cardiac arrest due to drowning are poor, and patients who are unconscious on admission to hospital have a guarded prognosis. [ABSTRACT FROM AUTHOR]

There is an old Chinese proverb that says: "Tell me and I will forget; Teach me and I might remember; Involve me and I will learn." This ancient proverb reflects the state of language retention and restoration. Living in a nation constructed of many diverse cultures provides teachers many unique conditions to their already challenging world of education. For centuries language was taught in the home and today the school is usually the place of language acquisition. Nowadays the two environments should work together to enhance exposure and success. Recently, much attention has been focused on the concept of bilingualism and the role of immersion. More and more of this attention is examining the role of immersion and its preference over the transitional bilingual approach (Kagan, 1990, p. 7). This urges us to carefully consider the impact that instructional media has on government and private schools in Ethiopia, which is a country of diversity in its culture and language. Hence, this research paper, "Instructional Media and its Impact on Government and Private Schools in Ethiopia" attempts to see if there exists any significant difference in the use of English as an instructional medium in both private and government schools and finally tries to perceive the cumulative effect that might happen due this difference. Apart from this, the paper also discusses the use of the vernacular language as medium of instruction and its possible impact on the learners. [ABSTRACT FROM AUTHOR]

Water covers over 75% of the earth, has a wide variety of depths and temperatures, and holds a great deal of the earth's resources. The challenges of the underwater environment are underappreciated and more short term compared with those of space travel. Immersion in water alters the cardio-endocrine-renal axis as there is an immediate translocation of blood to the heart and a slower autotransfusion of fluid from the cells to the vascular compartment. Both of these changes result in an increase in stroke volume and cardiac output. The stretch of the atrium and transient increase in blood pressure cause both endocrine and autonomic changes, which in the short term return plasma volume to control levels and decrease total peripheral resistance and thus regulate blood pressure. The reduced sympathetic nerve activity has effects on arteriolar resistance, resulting in hyperperfusion of some tissues, which for specific tissues is time dependent. The increased central blood volume results in increased pulmonary artery pressure and a decline in vital capacity. The effect of increased hydrostatic pressure due to the depth of submersion does not affect stroke volume; however, a bradycardia results in decreased cardiac output, which is further reduced during breath holding. Hydrostatic compression, however, leads to elastic loading of the chest wall and negative pressure breathing. The depth-dependent increased work of breathing leads to augmented respiratory muscle blood flow. The blood flow is increased to all lung zones with some improvement in the ventilation-perfusion relationship. The cardiac-renal responses are time dependent; however, the increased stroke volume and cardiac output are, during head-out immersion, sustained for at least hours. Changes in water temperature do not affect resting cardiac output; however, maximal cardiac output is reduced, as is peripheral blood flow, which results in reduced maximal exercise performance. In the cold, maximal cardiac output is reduced and skin and muscle are vasoconstricted, resulting in a further reduction in exercise capacity. [ABSTRACT FROM AUTHOR]

Abstract Water immersion is a frequent cause of accidental death and hospital admission. This article outlines the pathogenesis and principles of treatment. Drowning is defined as death by asphyxia due to submersion in a liquid medium. Near-drowning is defined as immediate survival after asphyxia due to submersion. [ABSTRACT FROM AUTHOR]

Background-Heart rate variability (HRV) describes the cyclic variations in heart rate and offers a non-invasive tool for investigating the modulatory effects of neural mechanisms elicited by the autonomic nervous system on intrinsic heart rate. Objective-To introduce the HRV concept to healthy volunteers under control conditions and during scuba diving. In contrast with more established manoeuvres, diving probably activates both the sympathetic and parasympathetic nervous system through various stimuli-for example, through cardiac stretch receptors, respiration pattern, psychological stress, and diving reflex. A further aim of the study was to introduce a measure for determining a candidate's ability to scuba dive by providing (a) standard values for HRV measures (three from the time domain and three from the frequency domain) and (b) physiological responses to a strenuous manoeuvre such as scuba diving. Methods-Twenty five trained scuba divers were investigated while diving under pool conditions (27°C) after the effects of head out immersion and submersion on HRV had been studied. Results and conclusions-(a) Immersion under pool conditions is a powerful stimulus for both the sympathetic and parasympathetic nervous system. (b) As neither the heart rate nor the HRV changed on going from immersion to submersion, the parasympathetic activation was probably due to haemodynamic alterations. (c) All HRV measures showed an increase in the parasympathetic activity. (d) If a physiological HRV is a mechanism for providing adaptability and flexibility, diving should not provoke circulatory problems in healthy subjects. (e) Either a lower than normal HRV under control conditions or a reduction in HRV induced by diving would be unphysiological, and a scuba diving candidate showing such characteristics should be further investigated. [ABSTRACT FROM AUTHOR]