WorldWideScience

Sample records for provisions commercial diving

  1. 46 CFR 197.430 - SCUBA diving.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false SCUBA diving. 197.430 Section 197.430 Shipping COAST... GENERAL PROVISIONS Commercial Diving Operations Specific Diving Mode Procedures § 197.430 SCUBA diving. The diving supervisor shall insure that— (a) SCUBA diving is not conducted— (1) Outside the no...

  2. 46 CFR 197.460 - Diving equipment.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Diving equipment. 197.460 Section 197.460 Shipping COAST... GENERAL PROVISIONS Commercial Diving Operations Periodic Tests and Inspections of Diving Equipment § 197.460 Diving equipment. The diving supervisor shall insure that the diving equipment designated for use...

  3. 46 CFR 197.432 - Surface-supplied air diving.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Surface-supplied air diving. 197.432 Section 197.432... STANDARDS GENERAL PROVISIONS Commercial Diving Operations Specific Diving Mode Procedures § 197.432 Surface-supplied air diving. The diving supervisor shall insure that— (a) Surface-supplied air diving is conducted...

  4. 46 CFR 197.210 - Designation of diving supervisor.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Designation of diving supervisor. 197.210 Section 197... HEALTH STANDARDS GENERAL PROVISIONS Commercial Diving Operations General § 197.210 Designation of diving supervisor. The name of the diving supervisor for each commercial diving operation shall be— (a) Designated...

  5. 46 CFR 197.320 - Diving ladder and stage.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Diving ladder and stage. 197.320 Section 197.320... STANDARDS GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.320 Diving ladder and stage. (a) Each diving ladder must— (1) Be capable of supporting the weight of at least two divers; (2) Extend 3...

  6. 46 CFR 197.334 - Open diving bells.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Open diving bells. 197.334 Section 197.334 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) MARINE OCCUPATIONAL SAFETY AND HEALTH STANDARDS GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.334 Open diving bells. Each open diving...

  7. 46 CFR 197.404 - Responsibilities of the diving supervisor.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Responsibilities of the diving supervisor. 197.404... SAFETY AND HEALTH STANDARDS GENERAL PROVISIONS Commercial Diving Operations Operations § 197.404 Responsibilities of the diving supervisor. (a) The diving supervisor shall— (1) Be fully cognizant of the...

  8. Performing CPR on a commercial diver inside the diving bell.

    Science.gov (United States)

    Bhutani, Sourabh; Verma, Rohit; Ghosh, Dipak Kumar

    2015-01-01

    CPR in a diving bell is difficult. It is taught by diving companies and training institutes but has not been subjected to the tenets of evidence based medicine. The diving bell lacks space as well as a flat hard surface to lay the patient on and therefore conventional methods of administering CPR are not possible. The diver is hung from a pulley tied to the diver's harness, and the bell flooded with water to reduce pooling of blood. Airway is established using a cervical collar to hyperextend the neck and inserting an appropriate oropharyngeal airway. Cardiac compressions are administered by the bellman using his head or the knee while holding the patient with his arms from behind. The bell can be recovered to surface only when spontaneous breathing and circulation have started. Diving bell offers a unique environment for management of unconscious casualties. Even though the method is at variance with the conventional method of administering CPR, it is the only method possible inside the bell. It is important that the method be scrutinized and refined so as to be more effective and efficacious inside the bell.

  9. 76 FR 67480 - Standard on Commercial Diving Operations; Extension of the Office of Management and Budget's (OMB...

    Science.gov (United States)

    2011-11-01

    ... Occupational Safety and Health Administration Standard on Commercial Diving Operations; Extension of the Office of Management and Budget's (OMB) Approval of Information Collection (Paperwork) Requirements AGENCY... requirements specified in the Commercial Diving Operations Standard (29 CFR part 1910, subpart T). DATES...

  10. 76 FR 9817 - Standard on Commercial Diving Operations; Extension of the Office of Management and Budget's (OMB...

    Science.gov (United States)

    2011-02-22

    ... conditions, or who control exposure of other employees to such conditions, in diving- related physics and...-related tasks, employers must ask each dive team member about their current state of physical fitness, and...

  11. 29 CFR 1910.424 - SCUBA diving.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false SCUBA diving. 1910.424 Section 1910.424 Labor Regulations... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Commercial Diving Operations Specific Operations Procedures § 1910.424 SCUBA diving. (a) General. Employers engaged in SCUBA diving shall comply with the following...

  12. Effects of diving on hearing and balance

    OpenAIRE

    Goplen, Frederik Kragerud

    2011-01-01

    Diving has profound effects on the human body including the inner ear, which contains the organs of hearing and balance. Ear injury is the most common medical problem in diving. The aim of this work was to explore the short and long-term effects of diving on hearing and balance through a simulated deep saturation dive and two epidemiological studies on commercial divers. The first study explored short-term effects of absolute pressure on the body. The high-pressure neurologi...

  13. 76 FR 63344 - Pilot Project on NAFTA Trucking Provisions; Commercial Driver's License Memorandum of...

    Science.gov (United States)

    2011-10-12

    ... for the United States-Mexico cross border long-haul trucking pilot program, the Secretary of... companies. Representatives from FMCSA visited nine training centers in Mexico in Nuevo Laredo, Tuiltitlan... [Docket No FMCSA-2011-0097] Pilot Project on NAFTA Trucking Provisions; Commercial Driver's License...

  14. Diving medicine.

    Science.gov (United States)

    Bove, Alfred A

    2014-06-15

    Exposure to the undersea environment has unique effects on normal physiology and can result in unique disorders that require an understanding of the effects of pressure and inert gas supersaturation on organ function and knowledge of the appropriate therapies, which can include recompression in a hyperbaric chamber. The effects of Boyle's law result in changes in volume of gas-containing spaces when exposed to the increased pressure underwater. These effects can cause middle ear and sinus injury and lung barotrauma due to lung overexpansion during ascent from depth. Disorders related to diving have unique presentations, and an understanding of the high-pressure environment is needed to properly diagnose and manage these disorders. Breathing compressed air underwater results in increased dissolved inert gas in tissues and organs. On ascent after a diving exposure, the dissolved gas can achieve a supersaturated state and can form gas bubbles in blood and tissues, with resulting tissue and organ damage. Decompression sickness can involve the musculoskeletal system, skin, inner ear, brain, and spinal cord, with characteristic signs and symptoms. Usual therapy is recompression in a hyperbaric chamber following well-established protocols. Many recreational diving candidates seek medical clearance for diving, and healthcare providers must be knowledgeable of the environmental exposure and its effects on physiologic function to properly assess individuals for fitness to dive. This review provides a basis for understanding the diving environment and its accompanying disorders and provides a basis for assessment of fitness for diving.

  15. Scientific Diving

    Science.gov (United States)

    Scientific diving plays an important role in helping EPA protect our oceans and waterways. EPA's divers set a high standard for safety and operational procedures in dangerous polluted water conditions.

  16. Neurological complications of underwater diving.

    Science.gov (United States)

    Rosińska, Justyna; Łukasik, Maria; Kozubski, Wojciech

    2015-01-01

    The diver's nervous system is extremely sensitive to high ambient pressure, which is the sum of atmospheric and hydrostatic pressure. Neurological complications associated with diving are a difficult diagnostic and therapeutic challenge. They occur in both commercial and recreational diving and are connected with increasing interest in the sport of diving. Hence it is very important to know the possible complications associated with this kind of sport. Complications of the nervous system may result from decompression sickness, pulmonary barotrauma associated with cerebral arterial air embolism (AGE), otic and sinus barotrauma, high pressure neurological syndrome (HPNS) and undesirable effect of gases used for breathing. The purpose of this review is to discuss the range of neurological symptoms that can occur during diving accidents and also the role of patent foramen ovale (PFO) and internal carotid artery (ICA) dissection in pathogenesis of stroke in divers. Copyright © 2014 Polish Neurological Society. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  17. Indicators of the ‘wild seafood’ provisioning ecosystem service based on the surplus production of commercial fish stocks

    NARCIS (Netherlands)

    Piet, G.J.; Overzee, van H.M.J.; Miller, D.C.M.; Gelabert, E.R.

    2017-01-01

    The ‘Wild Seafood’ Provisioning Service (WSPS), on which commercial fisheries rely, is probably one of the best studied marine ecosystem services due to its economic relevance and because extensive information sources exist for assessment purposes. Yet, the indicators often proposed are not

  18. 76 FR 61245 - Provision of Aviation Insurance Coverage for Commercial Air Carrier Service in Domestic and...

    Science.gov (United States)

    2011-10-03

    ... Coverage for Commercial Air Carrier Service in Domestic and International Operations #0; #0; #0... Aviation Insurance Coverage for Commercial Air Carrier Service in Domestic and International Operations...

  19. CERN Scuba Diving Club

    CERN Multimedia

    Club Subaquatique du CERN

    2017-01-01

    Interested in scuba diving? Fancy a fun trial dive? Like every year, the CERN Scuba Diving Club is organizing two free trial dive sessions. Where? Varembé Swimming Pool, Avenue Giuseppe Motta 46, 1202 Genève When? 25th October and 1st November at 19:15 (one session per participant) Price? Trial dives are FREE! Swimming pool entrance 5,40 CHF. What to bring? Swimwear, towel, shower necessities and a padlock – diving equipment will be provided by the CSC. For more information and to subscribe, follow the link below: http://cern.ch/csc-baptemes-2017 Looking forward to meeting you!

  20. 29 CFR Appendix C to Subpart T to... - Alternative Conditions Under § 1910.401(a)(3) for Recreational Diving Instructors and Diving...

    Science.gov (United States)

    2010-07-01

    ... Recreational Diving Instructors and Diving Guides (Mandatory) C Appendix C to Subpart T to Part 1910 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Commercial Diving Operations Pt. 1910, Subpt. T, App. C Appendix C to...

  1. Fabrication of a custom diving mouthpiece using a thermoforming material.

    Science.gov (United States)

    Matsui, Ryosuke; Ueno, Toshiaki; Ohyama, Takashi

    2004-10-01

    Scuba divers may suffer from temporomandibular joint dysfunction and related problems associated with the use of commercially available diving mouthpieces. Several authors have recommended that custom diving mouthpieces be fabricated for relieving the symptoms of diver's mouth syndrome. The lost wax technique is commonly used for this purpose but may be time-consuming and is technically complicated. This article describes a simplified technique using thermoforming material for fabricating a custom diving mouthpiece.

  2. Weight loss in a UK commercial all meal provision study: a randomised controlled trial.

    Science.gov (United States)

    Mellor, D D; Whitham, C; Goodwin, S; Morris, M; Reid, M; Atkin, S L

    2014-08-01

    Effective approaches are needed to address the increasing prevalence of overweight and obesity. The present study investigated whether all meal provision was a more effective and acceptable method for weight loss than a self-directed diet. This randomised controlled trial recruited 112 men and women with a body mass index in the range 27-35 kg m(-2), who had no comorbidities, from the local area of Hull. Participants were randomised to receive either meal provision or follow a self-directed diet for a 12-week period that resulted in an estimated 2928 kJ day(-1) (700 kcal day(-1)) deficit. A dietitian supervised both dietary interventions. At 12 weeks [mean (SEM)], percentage weight loss in the meal provision group was 6.6% (0.5%) compared to 4.3% (0.6%) for those on the self-directed diet. In terms of clinically relevant weight loss, 61% of participants lost 5% or more of their body weight with meal provision compared to 22% on the self-directed diet (P < 0.001). Weight loss was associated with wellbeing in both groups. Attrition was less apparent with 7% of those participants receiving meal provision withdrawing from the study compared to 41% of those following the self-directed diet (P < 0.001). Meal provision was a more effective and accepted method for weight loss over a 12-week period compared to a self-directed diet. This may in part represent the difference between being given the meal provision food free of charge. However, longer-term maintenance studies need to be undertaken to ascertain their effects on the maintenance of weight loss. © 2013 The Authors. Journal of Human Nutrition and Dietetics published by John Wiley & Sons Ltd on behalf of British Dietetic Association Ltd.

  3. 77 FR 66588 - Interim Procedures for Considering Requests Under the Commercial Availability Provision of the...

    Science.gov (United States)

    2012-11-06

    ... electronic copy must be submitted to OTEXA_COLOMBIA@trade.gov . All submitted comments will be posted for... of the United States-Colombia Trade Promotion Agreement AGENCY: Committee for the Implementation of... (``CITA'') will follow in implementing certain provisions of the ] United States-Colombia Trade Promotion...

  4. 76 FR 79166 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2011-12-21

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') AGENCY: The Committee for the Implementation of Textile Agreements ACTION: Determination to add a product... 21, 2011. SUMMARY: The Committee for the Implementation of Textile Agreements (``CITA'') has...

  5. 76 FR 78249 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2011-12-16

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') AGENCY: The Committee for the Implementation of Textile Agreements. ACTION: Determination to add a...: December 16, 2011. SUMMARY: The Committee for the Implementation of Textile Agreements (``CITA'') has...

  6. 75 FR 75664 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2010-12-06

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') AGENCY: The Committee for the Implementation of Textile Agreements. ACTION: Determination to add a...: December 6, 2010. SUMMARY: The Committee for the Implementation of Textile Agreements (``CITA'') has...

  7. 76 FR 16734 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2011-03-25

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') AGENCY: The Committee for the Implementation of Textile Agreements. ACTION: Determination to add a... Publication. SUMMARY: The Committee for the Implementation of Textile Agreements (``CITA'') has determined...

  8. 78 FR 16662 - Determination Under the Textile and Apparel Commercial Availability Provision of the United...

    Science.gov (United States)

    2013-03-18

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability... Committee for the Implementation of Textile Agreements. ACTION: Determination to add a product in...: The Committee for the Implementation of Textile Agreements (``CITA'') has determined that certain...

  9. 78 FR 39713 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2013-07-02

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') AGENCY: The Committee for the Implementation of Textile Agreements. ACTION: Determination to add a..., 2013. SUMMARY: The Committee for the Implementation of Textile Agreements (``CITA'') has determined...

  10. 77 FR 8221 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2012-02-14

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') AGENCY: The Committee for the Implementation of Textile Agreements. ACTION: Determination to add a...: February 14, 2012. SUMMARY: The Committee for the Implementation of Textile Agreements (``CITA'') has...

  11. 75 FR 65609 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2010-10-26

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') AGENCY: The Committee for the Implementation of Textile Agreements. ACTION: Determination to add a... 26, 2010. SUMMARY: The Committee for the Implementation of Textile Agreements (``CITA'') has...

  12. 78 FR 7414 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2013-02-01

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') AGENCY: The Committee for the Implementation of Textile Agreements. ACTION: Determination to add a...: February 1, 2013. SUMMARY: The Committee for the Implementation of Textile Agreements (``CITA'') has...

  13. 75 FR 48931 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2010-08-12

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') August 9, 2010. AGENCY: The Committee for the Implementation of Textile Agreements. ACTION: Determination... Date: August 12, 2010. SUMMARY: The Committee for the Implementation of Textile Agreements (``CITA...

  14. 78 FR 17642 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2013-03-22

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') AGENCY: The Committee for the Implementation of Textile Agreements. ACTION: Determination to add a... 22, 2013. SUMMARY: The Committee for the Implementation of Textile Agreements (``CITA'') has...

  15. 76 FR 52640 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2011-08-23

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') AGENCY: The Committee for the Implementation of Textile Agreements. ACTION: Determination to remove a.... SUMMARY: The Committee for the Implementation of Textile Agreements (``CITA'') has determined that an...

  16. 78 FR 18561 - Determination Under the Textile and Apparel Commercial Availability Provision of the United...

    Science.gov (United States)

    2013-03-27

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability... Committee for the Implementation of Textile Agreements. ACTION: Determination to add a product in...: The Committee for the Implementation of Textile Agreements (``CITA'') has determined that certain...

  17. 76 FR 67424 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2011-11-01

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') AGENCY: The Committee for the Implementation of Textile Agreements. ACTION: Determination to add a...: November 1, 2011. SUMMARY: The Committee for the Implementation of Textile Agreements (``CITA'') has...

  18. 78 FR 16661 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2013-03-18

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') AGENCY: The Committee for the Implementation of Textile Agreements. ACTION: Determination to add a... 18, 2013. SUMMARY: The Committee for the Implementation of Textile Agreements (``CITA'') has...

  19. 29 CFR Appendix B to Subpart T to... - Guidelines for Scientific Diving

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Guidelines for Scientific Diving B Appendix B to Subpart T... ADMINISTRATION, DEPARTMENT OF LABOR OCCUPATIONAL SAFETY AND HEALTH STANDARDS Commercial Diving Operations Pt. 1910, Subpt. T, App. B Appendix B to Subpart T to Part 1910—Guidelines for Scientific Diving This...

  20. Sickle cell trait and diving: review and recommendations.

    Science.gov (United States)

    Vigilante, John A; DiGeorge, Nicholas W

    2014-01-01

    Sickle cell trait, once thought to be a benign condition, has been associated with complications which may be of concern to the diver, such as splenic infarction and exercise-related sudden death. Medical clearance to dive for those with this common hemoglobinopathy has been a source of debate, with differing recommendations for both civilian and military candidates. To assess this disparity, a review was conducted of published findings and opinions regarding sickle cell trait and fitness to dive. Literature search was conducted using PubMed/Medline. Keywords included sickle cell trait, hemoglobinopathy, exercise-related sudden death, decompression sickness, diving, special operations, military. Results that included cases of sickle cell trait were included. Further, current guidelines were ascertained from public institutions, prominent diving texts, and the U.S. Military. Review of the literature reveals that complications of sickle cell trait are rare, with no reports of corresponding dive-related injury. Analysis of the physiology of diving as it pertains to the condition, as well as the absence of reported cases, suggest there is minimal increased risk in sport and technical civilian diving. Opinion for military fitness to dive is varied. As specific circumstances thought to predispose to sickle cell trait complication may be unavoidable in the completion of military duties, diving is not recommended for these individuals. However, recreational and commercial diving using typical precautions seems reasonable.

  1. 78 FR 11159 - Determination under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2013-02-15

    ..., accompanying the CAFTA-DR Implementation Act; and Presidential Proclamations 7987 (February 28, 2006) and 7996... comments and supporting evidence before a commercial availability determination is made. In Presidential.../sq. m/24 hours; 3x wash 500 g/sq. m per 24 hours. Remarks: Ranges above allow for a variance of up to...

  2. 78 FR 52907 - Determination Under the Textile and Apparel Commercial Availability Provision of the Dominican...

    Science.gov (United States)

    2013-08-27

    ... IMPLEMENTATION OF TEXTILE AGREEMENTS Determination Under the Textile and Apparel Commercial Availability...'') AGENCY: The Committee for the Implementation of Textile Agreements. ACTION: Determination to add a... Implementation of Textile Agreements (``CITA'') has determined that certain polyester/nylon cut corduroy fabric...

  3. Diving medicine in clinical practice.

    Science.gov (United States)

    Eichhorn, Lars; Leyk, Dieter

    2015-02-27

    Diving is a popular sport, and some recreational divers have medical risk factors. Their health can be endangered by high extracorporeal (ambient) pressure and its many systemic effects. We review relevant publications on free (breath-hold) diving, scuba diving, medical evaluation for diving, barotrauma, decompression sickness, and diving with medical risk factors, which were retrieved by a selective search of PubMed. Free diving or scuba diving, even at seemingly innocuous depths, puts considerable stress on the cardio - vascular system, ears, and lungs. Unexpected events while diving, diminished functional reserve, and pre-existing medical illnesses increase the risk of a diving accident. An international survey revealed that minor incidents occur in 1.3% of all dives, and decompression accidents in 2 of every 10 000 dives. A properly conducted medical examination to determine diving fitness, followed by appropriate counseling, can make a life-threatening diving accident less likely. To be able to certify diving fitness and give competent medical advice about diving, physicians must be well informed about the physical and physiological changes of diving and the associated risks to health, and they need to know how to perform a medical evaluation of prospective divers. In Germany, any licensed physician may judge a person fit to dive. It is recommended that this be done in adherence to the relevant evaluation standards and recommendations of the medical specialty associations. Randomized controlled trials on the effect of preventive behavior would be desirable, as would a central registry of diving accidents.

  4. Methodology scuba diving on tinge

    OpenAIRE

    Vondrášek, David

    2011-01-01

    Title: Methodology of apnea diving Objectives: The main objective of this work is to develop materials that could serve as a learning support students in basic studies of apnea diving. A part of the history of diving equipment and diving physiology of flavor and also methodologies apnea diving. Methods: Study of available sources. Literature available sources. Development of educational material using the material used and its own experience. Results: The result is a learning support for stud...

  5. The incidence of decompression illness in 10 years of scientific diving.

    Science.gov (United States)

    Dardeau, Michael R; Pollock, Neal W; McDonald, Christian M; Lang, Michael A

    2012-12-01

    The American Academy of Underwater Science (AAUS) constitutes the single largest pool of organizations with scientific diving programmes in North America. Members submit annual summaries of diving activity and any related incidents. All diving records for a 10-year period between January 1998 and December 2007 were reviewed. Incidents were independently classified or reclassified by a four-person panel with expertise in scientific diving and diving safety using a previously published protocol. Subsequent panel discussion produced a single consensus classification of each case. A total of 95 confirmed incidents were reported in conjunction with 1,019,159 scientific dives, yielding an overall incidence of 0.93/10,000 person-dives. A total of 33 cases were determined to involve decompression illness (DCI), encompassing both decompression sickness and air embolism. The incidence of DCI was 0.324/10,000 person-dives, substantially lower than the rates of 0.9-35.3/10,000 published for recreational, instructional/guided, commercial and/or military diving. Scientific diving safety may be facilitated by a combination of relatively high levels of training and oversight, the predominance of shallow, no-decompression diving and, possibly, low pressure to complete dives under less than optimal circumstances.

  6. Diving fatality investigations: recent changes.

    Science.gov (United States)

    Edmonds, Carl; Caruso, James

    2014-06-01

    Modifications to the investigation procedures in diving fatalities have been incorporated into the data acquisition by diving accident investigators. The most germane proposal for investigators assessing diving fatalities is to delay the drawing of conclusions until all relevant diving information is known. This includes: the accumulation and integration of the pathological data; the access to dive computer information; re-enactments of diving incidents; post-mortem CT scans and the interpretation of intravascular and tissue gas detected. These are all discussed, with reference to the established literature and recent publications.

  7. [Case report: fatal diving-accident. Or: accident while diving?].

    Science.gov (United States)

    Böttcher, F; Jüttner, B; Krause, A; Rocha, M; Koppert, W

    2012-02-01

    This example of a fatal diving accident shows how challenging such cases can be in pre-hospital and clinical care. There is no common mechanism in diving fatalities and more than one group of disorders coming along with decompression sickness. Diving medicine is not an element of medical education, which results in insecurity and hampers adequate therapy of diving incidents. This is aggravated by an insufficient availability of hyperbaric chambers in Germany.

  8. Diving Medicine: Frequently Asked Questions

    Science.gov (United States)

    ... Malaria Medicines & Diving Medical Questionnaire / Statement Can the truth hurt? Is it dangerous to be totally honest ... headaches can affect diving. Multiple Sclerosis (MS) Paraplegia Post Brain Tumor Surgery Ophthalmology (Eyes) Blurred Vision Detached ...

  9. Can asthmatic subjects dive?

    Directory of Open Access Journals (Sweden)

    Yochai Adir

    2016-06-01

    Full Text Available Recreational diving with self-contained underwater breathing apparatus (scuba has grown in popularity. Asthma is a common disease with a similar prevalence in divers as in the general population. Due to theoretical concern about an increased risk for pulmonary barotrauma and decompression sickness in asthmatic divers, in the past the approach to asthmatic diver candidates was very conservative, with scuba disallowed. However, experience in the field and data in the current literature do not support this dogmatic approach. In this review the theoretical risk factors of diving with asthma, the epidemiological data and the recommended approach to the asthmatic diver candidate will be described.

  10. Dive Into Python 3

    CERN Document Server

    Pilgrim, Mark

    2009-01-01

    Mark Pilgrim's Dive Into Python 3 is a hands-on guide to Python 3 (the latest version of the Python language) and its differences from Python 2. As in the original book, Dive Into Python, each chapter starts with a real, complete code sample, proceeds to pick it apart and explain the pieces, and then puts it all back together in a summary at the end. This book includes: * Example programs completely rewritten to illustrate powerful new concepts now available in Python 3: sets, iterators, generators, closures, comprehensions, and much more* A detailed case study of porting a major library from

  11. ASSESSMENT OF PLUME DIVING

    Science.gov (United States)

    This presentation presents an assessment of plume diving. Observations included: vertical plume delineation at East Patchogue, NY showed BTEX and MTBE plumes sinking on either side of a gravel pit; Lake Druid TCE plume sank beneath unlined drainage ditch; and aquifer recharge/dis...

  12. Toppling Techniques in Diving

    Science.gov (United States)

    Wilson, Barry D.

    1977-01-01

    This paper demonstrates that in a toppling dive (1) a 1:1 ratio exists between the rotational speed of the diver immediately before and after the take-off and (2) the take-off angle as defined by Page is approximately 50 percent. (Author)

  13. Short- and long-term effects of diving on pulmonary function.

    Science.gov (United States)

    Tetzlaff, Kay; Thomas, Paul S

    2017-03-31

    The diving environment provides a challenge to the lung, including exposure to high ambient pressure, altered gas characteristics and cardiovascular effects on the pulmonary circulation. Several factors associated with diving affect pulmonary function acutely and can potentially cause prolonged effects that may accumulate gradually with repeated diving exposure. Evidence from experimental deep dives and longitudinal studies suggests long-term adverse effects of diving on the lungs in commercial deep divers, such as the development of small airways disease and accelerated loss of lung function. In addition, there is an accumulating body of evidence that diving with self-contained underwater breathing apparatus (scuba) may not be associated with deleterious effects on pulmonary function. Although changes in pulmonary function after single scuba dives have been found to be associated with immersion, ambient cold temperatures and decompression stress, changes in lung function were small and suggest a low likelihood of clinical significance. Recent evidence points to no accelerated loss of lung function in military or recreational scuba divers over time. Thus, the impact of diving on pulmonary function largely depends on factors associated with the individual diving exposure. However, in susceptible subjects clinically relevant worsening of lung function may occur even after single shallow-water scuba dives. Copyright ©ERS 2017.

  14. Short- and long-term effects of diving on pulmonary function

    Directory of Open Access Journals (Sweden)

    Kay Tetzlaff

    2017-03-01

    Full Text Available The diving environment provides a challenge to the lung, including exposure to high ambient pressure, altered gas characteristics and cardiovascular effects on the pulmonary circulation. Several factors associated with diving affect pulmonary function acutely and can potentially cause prolonged effects that may accumulate gradually with repeated diving exposure. Evidence from experimental deep dives and longitudinal studies suggests long-term adverse effects of diving on the lungs in commercial deep divers, such as the development of small airways disease and accelerated loss of lung function. In addition, there is an accumulating body of evidence that diving with self-contained underwater breathing apparatus (scuba may not be associated with deleterious effects on pulmonary function. Although changes in pulmonary function after single scuba dives have been found to be associated with immersion, ambient cold temperatures and decompression stress, changes in lung function were small and suggest a low likelihood of clinical significance. Recent evidence points to no accelerated loss of lung function in military or recreational scuba divers over time. Thus, the impact of diving on pulmonary function largely depends on factors associated with the individual diving exposure. However, in susceptible subjects clinically relevant worsening of lung function may occur even after single shallow-water scuba dives.

  15. Neurology and diving.

    Science.gov (United States)

    Massey, E Wayne; Moon, Richard E

    2014-01-01

    Diving exposes a person to the combined effects of increased ambient pressure and immersion. The reduction in pressure when surfacing can precipitate decompression sickness (DCS), caused by bubble formation within tissues due to inert gas supersaturation. Arterial gas embolism (AGE) can also occur due to pulmonary barotrauma as a result of breath holding during ascent or gas trapping due to disease, causing lung hyperexpansion, rupture and direct entry of alveolar gas into the blood. Bubble disease due to either DCS or AGE is collectively known as decompression illness. Tissue and intravascular bubbles can induce a cascade of events resulting in CNS injury. Manifestations of decompression illness can vary in severity, from mild (paresthesias, joint pains, fatigue) to severe (vertigo, hearing loss, paraplegia, quadriplegia). Particularly as these conditions are uncommon, early recognition is essential to provide appropriate management, consisting of first aid oxygen, targeted fluid resuscitation and hyperbaric oxygen, which is the definitive treatment. Less common neurologic conditions that do not require hyperbaric oxygen include rupture of a labyrinthine window due to inadequate equalization of middle ear pressure during descent, which can precipitate vertigo and hearing loss. Sinus and middle ear overpressurization during ascent can compress the trigeminal and facial nerves respectively, causing temporary facial hypesthesia and lower motor neuron facial weakness. Some conditions preclude safe diving, such as seizure disorders, since a convulsion underwater is likely to be fatal. Preventive measures to reduce neurologic complications of diving include exclusion of individuals with specific medical conditions and safe diving procedures, particularly related to descent and ascent. © 2014 Elsevier B.V. All rights reserved.

  16. The Methodical Approach to Formation of the Economic-Social Provision of the Financial Security Management of Commercial Bank

    Directory of Open Access Journals (Sweden)

    Baryliuk Mariia-Mariana R.

    2017-06-01

    Full Text Available The article defines that the impact of threats on a commercial bank as an open socio-economic system results in losses that can be classified as financial, personnel, informational, and reputational. In terms of temporal horizons, losses are defined as tactical and strategic. Possible losses from external and internal threat implications have been determined, which have resulted in the development of a four-level structure of total losses from threat implications for the financial security of commercial bank. The proposed sequence of calculations for integrated assessment of threats impact provides an information basis for the development and introducing a set of interrelated organizational-economic measures to implement changes in the subsystem of financial security of commercial bank. The level of threats identified, the nature and extent of financial, personnel, information, and reputational losses are the basis for more efficient use of available resources and for improving the financial security management of commercial bank.

  17. Cerebral damage in diving: Taking the cue from sports concussion ...

    African Journals Online (AJOL)

    Taking the cue from sports concussion medicine, it is proposed that there is an urgent need to incorporate neurocognitive baseline and follow-up screening as a core component in the medical management of those involved in intensive commercial and recreational compressed air diving activities. The objective would be to ...

  18. [Oxygen therapy in diving accidents].

    Science.gov (United States)

    Piepho, T; Ehrmann, U; Werner, C; Muth, C M

    2007-01-01

    Diving accidents represent a departure from the routine practice of emergency physicians. The incidence of non-fatal diving accidents is reported as 1-2 per 10,000 dives. Apart from adequate intravenous hydration, oxygen is the only medication with a proven effect in the treatment of diving accidents. After a typical diving accident, administration of oxygen at an inspired concentration (F(I)O(2) 1.0) as high as possible is recommended. Many divers bring along their own oxygen administration systems to the diving sites and these are often better suited for the treatment of diving accidents than the oxygen systems of many emergency responders. Pressure regulators supplying low constant flow oxygen, nasal prongs and inhalation masks are inappropriate. When using artificial ventilation bags with face masks, an oxygen flow of at least 15 l/min should be used. Demand regulators are simple to use and able to deliver a F(I)O2 of 1.0. Their ease of use has earned them high marks in the emergency management of diving accidents and their similarity to standard diving equipment has also aided relatively widespread acceptance. Circulation breathing systems are more technologically complex oxygen delivery systems which permit CO2 absorption and re-breathing at low oxygen flow. In contrast to the demand modules, the likelihood of mistakes during their usage is higher. In diving accidents, the administration of normobaric oxygen, already begun in the field, is the most important therapy and should not be interrupted. Presented with an inadequate supplemental oxygen supply, the inspired oxygen concentration should not be decreased, rather the duration of the oxygen administration should be reduced. Hyperbaric oxygen therapy should be the mainstay of further treatment.

  19. Long-Term Changes in Species Composition and Relative Abundances of Sharks at a Provisioning Site

    OpenAIRE

    Brunnschweiler, Juerg M; Abrantes, Kátya G.; Barnett, Adam

    2014-01-01

    Diving with sharks, often in combination with food baiting/provisioning, has become an important product of today’s recreational dive industry. Whereas the effects baiting/provisioning has on the behaviour and abundance of individual shark species are starting to become known, there is an almost complete lack of equivalent data from multi-species shark diving sites. In this study, changes in species composition and relative abundances were determined at the Shark Reef Marine Reserve, a multi-...

  20. 43 CFR 15.8 - Skin diving.

    Science.gov (United States)

    2010-10-01

    ... 43 Public Lands: Interior 1 2010-10-01 2010-10-01 false Skin diving. 15.8 Section 15.8 Public Lands: Interior Office of the Secretary of the Interior KEY LARGO CORAL REEF PRESERVE § 15.8 Skin diving. Diving with camera, or diving for observation and pleasure is permitted and encouraged within the...

  1. Commercial surrogacy: how provisions of monetary remuneration and powers of international law can prevent exploitation of gestational surrogates.

    Science.gov (United States)

    Ramskold, Louise Anna Helena; Posner, Marcus Paul

    2013-06-01

    Increasing globalisation and advances in artificial reproductive techniques have opened up a whole new range of possibilities for infertile couples across the globe. Inter-country gestational surrogacy with monetary remuneration is one of the products of medical tourism meeting in vitro fertilisation embryo transfer. Filled with potential, it has also been a hot topic of discussion in legal and bioethics spheres. Fears of exploitation and breach of autonomy have sprung from the current situation, where there is no international regulation of surrogacy agreements--only a web of conflicting national laws that generates loopholes and removes safeguards for both the surrogate and commissioning couple. This article argues the need for evidence-based international laws and regulations as the only way to resolve both the ethical and legal issues around commercial surrogacy. In addition, a Hague Convention on inter-country surrogacy agreements is proposed to resolve the muddled state of affairs and enable commercial surrogacy to demonstrate its full potential.

  2. Diving and Environmental Simulation Team

    Data.gov (United States)

    Federal Laboratory Consortium — The Diving and Environmental Simulation Team focuses on ways to optimize the performance and safety of Navy divers. Our goal is to increase mission effectiveness by...

  3. Potential Benefits of Navy Dive Computer Use in Ships Husbandry Diving: Analysis of Dives Conducted at Puget Sound Naval Shipyard

    National Research Council Canada - National Science Library

    Gault, Keith A

    2008-01-01

    Generation III Air Navy Dive Computers (AIR III) were used to record 315 ships husbandry dives conducted by divers breathing air at the Puget Sound Naval Shipyard from November 2007 to January 2008...

  4. 29 CFR 1926.1084 - SCUBA diving.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false SCUBA diving. 1926.1084 Section 1926.1084 Labor Regulations...) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Diving Specific Operations Procedures § 1926.1084 SCUBA diving. Note: The requirements applicable to construction work under this section are identical to those...

  5. 33 CFR 146.40 - Diving casualties.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Diving casualties. 146.40 Section 146.40 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES OPERATIONS OCS Facilities § 146.40 Diving casualties. Diving related casualties...

  6. Accident rates at a busy diving centre.

    Science.gov (United States)

    Davis, Michael; Malcolm, Kate

    2008-06-01

    Dear Editor, The Poor Knights Islands in Northland, New Zealand, is a world-famous, temperate-water, diving tourism destination, popularised many years ago by Jacques Cousteau. By far the largest dive operator there is Dive! Tutukaka, with five vessels carrying up to 30 divers, operating on a regular basis throughout the year. Dive! Tutukaka is required to keep a detailed, daily vessel manifest. Thus, the number of divers is known accurately and all incidents are recorded by the Skipper or the Chief Divemaster on board. Although all dives are logged (time in, time out and maximum depth for every diver) and kept permanently, these data were not utilised for this brief report. Each customer does two dives on a trip and there are between one and four divemasters on board who may do one, two or more dives a day (van der Hulst G, unpublished observations). Thus the accident rate per diver is known, and it is assumed that the rate per dive is very close to half this figure. In addition, under health and safety regulations all non-diving injuries both on shore and on board are documented, but these will include some non-divers. For the three financial years between July 2005 and 14 June 2008, 32,302 customers dived with Dive! Tutukaka, approximately 63,000 dives (a small minority did only one dive). Over the same period, there were an estimated 7,600 dives conducted by the divemasters. The injuries documented during this time are shown in Table 1. There were seven cases of decompression illness (DCI), a rate of about 1 per 10,000 divers (0.5 per 10,000 dives). Two of the seven DCI cases involved serious neurological injury. There was one further possible case of DCI who did not seek medical advice. If this diver is included then the rate is 1.14 per 10,000 divers. More minor diving injuries and incidents occurred at a rate of approximately 2 per 10,000 divers. Non-diving injuries occurred rarely, the most common being various musculo-skeletal injuries to staff, requiring

  7. Recreational technical diving part 2: decompression from deep technical dives.

    Science.gov (United States)

    Doolette, David J; Mitchell, Simon J

    2013-06-01

    Technical divers perform deep, mixed-gas 'bounce' dives, which are inherently inefficient because even a short duration at the target depth results in lengthy decompression. Technical divers use decompression schedules generated from modified versions of decompression algorithms originally developed for other types of diving. Many modifications ostensibly produce shorter and/or safer decompression, but have generally been driven by anecdote. Scientific evidence relevant to many of these modifications exists, but is often difficult to locate. This review assembles and examines scientific evidence relevant to technical diving decompression practice. There is a widespread belief that bubble algorithms, which redistribute decompression in favour of deeper decompression stops, are more efficient than traditional, shallow-stop, gas-content algorithms, but recent laboratory data support the opposite view. It seems unlikely that switches from helium- to nitrogen-based breathing gases during ascent will accelerate decompression from typical technical bounce dives. However, there is evidence for a higher prevalence of neurological decompression sickness (DCS) after dives conducted breathing only helium-oxygen than those with nitrogen-oxygen. There is also weak evidence suggesting less neurological DCS occurs if helium-oxygen breathing gas is switched to air during decompression than if no switch is made. On the other hand, helium-to-nitrogen breathing gas switches are implicated in the development of inner-ear DCS arising during decompression. Inner-ear DCS is difficult to predict, but strategies to minimize the risk include adequate initial decompression, delaying helium-to-nitrogen switches until relatively shallow, and the use of the maximum safe fraction of inspired oxygen during decompression.

  8. Diving down the reefs? Intensive diving tourism threatens the reefs of the northern Red Sea.

    Science.gov (United States)

    Hasler, Harald; Ott, Jörg A

    2008-10-01

    Intensive recreational SCUBA diving threatens coral reef ecosystems. The reefs at Dahab, South Sinai, Egypt, are among the world's most dived (>30,000 dives y(-1)). We compared frequently dived sites to sites with no or little diving. Benthic communities and condition of corals were examined by the point intercept sampling method in the reef crest zone (3m) and reef slope zone (12 m). Additionally, the abundance of corallivorous and herbivorous fish was estimated based on the visual census method. Sediments traps recorded the sedimentation rates caused by SCUBA divers. Zones subject to intensive SCUBA diving showed a significantly higher number of broken and damaged corals and significantly lower coral cover. Reef crest coral communities were significantly more affected than those of the reef slope: 95% of the broken colonies were branching ones. No effect of diving on the abundance of corallivorous and herbivorous fish was evident. At heavily used dive sites, diver-related sedimentation rates significantly decreased with increasing distance from the entrance, indicating poor buoyancy regulation at the initial phase of the dive. The results show a high negative impact of current SCUBA diving intensities on coral communities and coral condition. Corallivorous and herbivorous fishes are apparently not yet affected, but are endangered if coral cover decline continues. Reducing the number of dives per year, ecologically sustainable dive plans for individual sites, and reinforcing the environmental education of both dive guides and recreational divers are essential to conserve the ecological and the aesthetic qualities of these dive sites.

  9. Diving exposure and health effects in divers working in different areas of professional diving.

    Science.gov (United States)

    Irgens, Ågot; Troland, Kari; Djurhuus, Rune; Grønning, Marit

    2016-01-01

    The aim of the present study was to compare diving exposure and health effects in different areas of professional diving. The Norwegian Labour Inspection Authority's Diving Register contains data on all professional inshore divers who have held a diving certificate at any time since 1980. Of these divers, the "Norwegian diver 2011" questionnaire was completed by 2848 (48.7%). A total of 1167 male divers reported that they often worked in one area of diving only (rescue diving, diving instruction, fish farming, quay/construction work and offshore/oil related). In the analysis of these divers, rescue divers were used as referents as they reported the lowest number of dives. Age distribution, the proportion of retired divers and the mean number of dives completed varied between the different areas of professional diving. Compared to rescue divers, divers in fish farming, quay/ /construction work and offshore/oil related work more often experienced physically demanding diving. Divers in fish farming more often had no day off after 3 days of physically demanding work compared to rescue divers. All groups except offshore divers reported making further dives after one physically demanding dive on the same day. All groups reported more frequent decompression sickness than did the referents and divers in quay/construction and offshore/oil related diving reported more frequent episodes of unconsciousness during diving than did the referents. Divers in fish farming, in quay/construction work and oil/ /offshore related diving obtained a higher symptom score than the referents and the two latter groups also reported more frequent adverse health effects due to diving than the referents. Health related physical and mental component summary scores were lower in all other groups than in referents. Compared to the rescue divers, divers in quay/construction work and offshore/oil related divers reported more adverse health effects and obtained a higher symptom score.

  10. High diving metabolism results in a short aerobic dive limit for Steller sea lions (Eumetopias jubatus).

    Science.gov (United States)

    Gerlinsky, Carling D; Rosen, David A S; Trites, Andrew W

    2013-07-01

    The diving capacity of marine mammals is typically defined by the aerobic dive limit (ADL) which, in lieu of direct measurements, can be calculated (cADL) from total body oxygen stores (TBO) and diving metabolic rate (DMR). To estimate cADL, we measured blood oxygen stores, and combined this with diving oxygen consumption rates (VO2) recorded from 4 trained Steller sea lions diving in the open ocean to depths of 10 or 40 m. We also examined the effect of diving exercise on O2 stores by comparing blood O2 stores of our diving animals to non-diving individuals at an aquarium. Mass-specific blood volume of the non-diving individuals was higher in the winter than in summer, but there was no overall difference in blood O2 stores between the diving and non-diving groups. Estimated TBO (35.9 ml O2 kg(-1)) was slightly lower than previously reported for Steller sea lions and other Otariids. Calculated ADL was 3.0 min (based on an average DMR of 2.24 L O2 min(-1)) and was significantly shorter than the average 4.4 min dives our study animals performed when making single long dives-but was similar to the times recorded during diving bouts (a series of 4 dives followed by a recovery period on the surface), as well as the dive times of wild animals. Our study is the first to estimate cADL based on direct measures of VO2 and blood oxygen stores for an Otariid and indicates they have a much shorter ADL than previously thought.

  11. Shallow Water Diving - The NASA Experience

    Science.gov (United States)

    Fitzpatrick, Daniel; Kelsey-Seybold

    2010-01-01

    This slide presentation reviews some of the problems and solutions that personnel have experienced during sessions in the Neutral Bu0yancy Lab (NBL). It reviews the standard dive that occurs at the NBL, Boyles and Henry's laws as they relate to the effects of diving. It then reviews in depth some of the major adverse physiologic events that happen during a diving session: Ear and Sinus Barotrauma, Decompression Sickness, (DCS), Pulmonary Barotrauma (i.e., Arterial Gas Embolism (AGE). Mediastinal Emphysema, Subcutaneous Emphysema, and Pneumothorax) Oxygen Toxicity and Hypothermia. It includes information about the pulmonary function in NBL divers. Also included is recommendations about flying after diving.

  12. Decompression sickness in breath-hold diving, and its probable connection to the growth and dissolution of small arterial gas emboli.

    Science.gov (United States)

    Goldman, Saul; Solano-Altamirano, J M

    2015-04-01

    We solved the Laplace equation for the radius of an arterial gas embolism (AGE), during and after breath-hold diving. We used a simple three-region diffusion model for the AGE, and applied our results to two types of breath-hold dives: single, very deep competitive-level dives and repetitive shallower breath-hold dives similar to those carried out by indigenous commercial pearl divers in the South Pacific. Because of the effect of surface tension, AGEs tend to dissolve in arterial blood when arteries remote from supersaturated tissue. However if, before fully dissolving, they reach the capillary beds that perfuse the brain and the inner ear, they may become inflated with inert gas that is transferred into them from these contiguous temporarily supersaturated tissues. By using simple kinetic models of cerebral and inner ear tissue, the nitrogen tissue partial pressures during and after the dive(s) were determined. These were used to theoretically calculate AGE growth and dissolution curves for AGEs lodged in capillaries of the brain and inner ear. From these curves it was found that both cerebral and inner ear decompression sickness are expected to occur occasionally in single competitive-level dives. It was also determined from these curves that for the commercial repetitive dives considered, the duration of the surface interval (the time interval separating individual repetitive dives from one another) was a key determinant, as to whether inner ear and/or cerebral decompression sickness arose. Our predictions both for single competitive-level and repetitive commercial breath-hold diving were consistent with what is known about the incidence of cerebral and inner ear decompression sickness in these forms of diving. Copyright © 2015 Elsevier Inc. All rights reserved.

  13. Diving with pre-existing medical conditions.

    Science.gov (United States)

    Lippmann, John; McD Taylor, David; Stevenson, Christopher; Williams, Jo; Mitchell, Simon J

    2017-09-01

    This is the second report based on a survey of Divers Alert Network Asia-Pacific (DAN AP) members who dive with cardiovascular and respiratory conditions and diabetes. It examines the medical management of the divers' conditions, any diving modifications used to mitigate the risk and outcomes. An online cross-sectional survey was sent to 833 divers who had declared a targeted medical condition when applying for DAN AP membership between July 2009 and August 2013. Two-hundred-and-sixty-eight respondents (32%) provided sufficient information on their conditions to be included in the analyses. These included ischaemic heart disease (31), arrhythmias (20), cardiac septal defects (31), other cardiac conditions (10), hypertension (127), diabetes (25), asthma (40) and pneumothorax (5). Forty-nine per cent had sought specialist diving medical advice about their condition and 23% reported modifying their diving practices to mitigate their risk. The cohort had completed 183,069 career dives, 57,822 of these since being diagnosed with their medical condition. There were 27 individuals who reported having decompression illness (25 of whom were subsequently diagnosed with a persistent foramen ovale), and two individuals who experienced an arrhythmia during diving. Some DAN AP members are diving with medical conditions which could potentially impact the safety of their diving. A minority modified their diving practices to mitigate the risk of their condition and approximately half sought specialist diving medical advice. The incidence of diving-related problems precipitated by known and managed pre-existing health conditions seems low but further studies of larger cohorts and incorporating fatality data would be necessary to confirm this. These results are limited by the 32% response rate and potential for bias towards selection of those most careful with their health.

  14. Diving the wreck: risk and injury in sport scuba diving.

    Science.gov (United States)

    Hunt, J C

    1996-07-01

    This paper utilizes psychoanalytic theory to examine risk and injury in the case of a male deep sea diver. It examines the unconscious conflicts which appeared to fuel the diver's involvement in deep diving and to lead to a near fatal incident of decompression sickness. Particular attention is paid to the role of the diver's father in the evolution of the preoedipal and oedipal fantasies and conflicts which appear to be linked to the injury. The research is based on interviews with and fieldwork among recreational and deep divers.

  15. Flying after diving: in-flight echocardiography after a scuba diving week.

    Science.gov (United States)

    Cialoni, Danilo; Pieri, Massimo; Balestra, Costantino; Marroni, Alessandro

    2014-10-01

    Flying after diving may increase decompression sickness risk (DCS), but strong evidence indicating minimum preflight surface intervals (PFSI) is missing. On return flights after a diving week on a live-aboard, 32 divers were examined by in-flight echocardiography with the following protocol: 1) outgoing flight, no previous dive; 2) during the diving week; 3) before the return flight after a 24-h PFSI; and 4) during the return flight. All divers completed similar multiple repetitive dives during the diving week. All dives were equivalent as to inert gas load and gradient factor upon surfacing. No bubbles in the right heart were found in any diver during the outgoing flight or at the preflight control after a 24-h PFSI following the diving week. A significant increase in the number and grade of bubbles was observed during the return flight. However, bubbles were only observed in 6 of the 32 divers. These six divers were the same ones who developed bubbles after every dive. Having observed a 24-h preflight interval, the majority of divers did not develop bubbles during altitude exposure; however, it is intriguing to note that the same subjects who developed significant amounts of bubbles after every dive showed equally significant bubble grades during in-flight echocardiography notwithstanding a correct PFSI. This indicates a possible higher susceptibility to bubble formation in certain individuals, who may need longer PFSI before altitude exposure after scuba diving.

  16. Diving down the reefs? Intensive diving tourism threatens the reefs of the northern Red Sea

    DEFF Research Database (Denmark)

    Hasler-Sheetal, Harald; Ott, Jörg A.

    2008-01-01

    Intensive recreational SCUBA diving threatens coral reef ecosystems. The reefs at Dahab, South Sinai, Egypt, are among the world’s most dived (>30,000dives y−1). We compared frequently dived sites to sites with no or little diving. Benthic communities and condition of corals were examined...... to intensive SCUBA diving showed a significantly higher number of broken and damaged corals and significantly lower coral cover. Reef crest coral communities were significantly more affected than those of the reef slope: 95% of the broken colonies were branching ones. No effect of diving on the abundance...... by the point intercept sampling method in the reef crest zone (3 m) and reef slope zone (12 m). Additionally, the abundance of corallivorous and herbivorous fish was estimated based on the visual census method. Sediments traps recorded the sedimentation rates caused by SCUBA divers. Zones subject...

  17. Teaching Persons with Disabilities to SCUBA Diving.

    Science.gov (United States)

    Jankowski, Louis W.

    This booklet is designed to sensitize and inform the scuba diving instructor on appropriate attitudes and successful methods for teaching scuba diving to persons with physical disability. It addresses misconceptions about people with disabilities and the importance of effective two-way communication and mutual respect between instructors and…

  18. Introduction to Scuba Diving. Diver Education Series.

    Science.gov (United States)

    Somers, Lee H.

    Scuba diving is often referred to as a "recreational sport." However, the term "sport" sometimes implies erroneous connotations and limits understanding. Scuba diving can be an avocation or a vocation. It is a pastime, a pursuit, or even a lifestyle, that can be as limited or extensive as one makes it. A persons level of commitment, degree of…

  19. How seabirds plunge-dive without injuries

    Science.gov (United States)

    Chang, Brian; Croson, Matthew; Straker, Lorian; Gart, Sean; Dove, Carla; Gerwin, John; Jung, Sunghwan

    In nature, several seabirds (e.g., gannets and boobies) dive into water at up to 24 m/s as a hunting mechanism; furthermore, gannets and boobies have a slender neck, which is potentially the weakest part of the body under compression during high-speed impact. In this work, we investigate the stability of the bird's neck during plunge-diving by understanding the interaction between the fluid forces acting on the head and the flexibility of the neck. First, we use a salvaged bird to identify plunge-diving phases. Anatomical features of the skull and neck were acquired to quantify the effect of beak geometry and neck musculature on the stability during a plunge-dive. Second, physical experiments using an elastic beam as a model for the neck attached to a skull-like cone revealed the limits for the stability of the neck during the bird's dive as a function of impact velocity and geometric factors. We find that the neck length, neck muscles, and diving speed of the bird predominantly reduce the likelihood of injury during the plunge-dive. Finally, we use our results to discuss maximum diving speeds for humans to avoid injury.

  20. The Physics of Breath-Hold Diving.

    Science.gov (United States)

    Aguilella, Vicente; Aguilella-Arzo, Marcelo

    1996-01-01

    Analyzes physical features of breath-hold diving. Considers the diver's descent and the initial surface dive and presents examples that show the diver's buoyancy equilibrium varying with depth, the driving force supplied by finning, and the effect of friction between the water and the diver. (Author/JRH)

  1. 29 CFR 1910.410 - Qualifications of dive team.

    Science.gov (United States)

    2010-07-01

    ... Requirements § 1910.410 Qualifications of dive team. (a) General. (1) Each dive team member shall have the... physiology. (b) Assignments. (1) Each dive team member shall be assigned tasks in accordance with the... assigned diving operation. General Operations Procedures ...

  2. 29 CFR 1910.426 - Mixed-gas diving.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Mixed-gas diving. 1910.426 Section 1910.426 Labor... Mixed-gas diving. (a) General. Employers engaged in mixed-gas diving shall comply with the following requirements, unless otherwise specified. (b) Limits. Mixed-gas diving shall be conducted only when: (1) A...

  3. The death of buddy diving?

    Science.gov (United States)

    Cooper, P David

    2011-12-01

    Dear Editor, By focussing on the details of the Watson case, I believe Bryan Walpole has missed the thrust of my earlier letter. I agree this was a complex case, which is why I deliberately avoided the murky specifics in order to consider the 'big-picture' ramifications of the judgement. My concerns relate to the potential consequences of the unintended interplay between unrelated developments in the medical and legal arenas. Taken together, I believe these developments threaten the very institution of buddy diving. I have been unable to verify Dr Walpole's claim that the statute under which Mr Watson was convicted has not been used previously in a criminal trial. I must, however, refute his assertion that this legislation is some sort of idiosyncratic historical hangover or legal curiosity unique to Queensland. Although the original legislation pre-dates Australian federation, this statute has survived intact through 110 years of reviews and amendments to the Queensland Criminal Code. The application of this 19th century law to the Watson case now provides a direct, post-federation, 21st century relevance. Nor is Queensland alone in having such a statute on its books. Section 151 of the Criminal Code Act in Dr Walpole's home state of Tasmania states "When a person undertakes to do any act, the omission to do which is or may be dangerous to human life or health, it is his duty to do that act." Similar statutes can also be found in the legislation of other Australian states and as far afield as New Zealand and Canada. The phrasing of the relevant sections is, in many cases, almost identical to Queensland's, reflecting the common judicial heritage of these places. Even if this ruling's reach extended no further than the Queensland border its ramifications would be immense. Tourism statistics reveal that over 1.2 million visitors perform nearly 3.5 million dives/snorkels in Queensland each year. An estimated 93% of international divers visiting Australia stopover in

  4. A case of bilateral ophthalmoplegia while diving.

    Science.gov (United States)

    Lee, Blair C; Young, Colin R

    2015-01-01

    This case report presents a military diver who became dysphoric and lost consciousness during a routine surface-supplied dive. The patient regained consciousness spontaneously, but the physical exam was notable for bilateral ophthalmoplegia. Full eye movement was regained during hyperbaric oxygen (HBO2) therapy, and the patient subsequently made a full recovery. Equipment and dive profile analysis led to the conclusion of hypercapnia and arterial gas embolism as the probable causes of the diver's symptoms. This is a unique case of isolated bilateral ophthalmoplegia presenting in a diving injury.

  5. Measurement of flying and diving metabolic rate in wild animals: Review and recommendations.

    Science.gov (United States)

    Elliott, Kyle H

    2016-12-01

    Animals' abilities to fly long distances and dive to profound depths fascinate earthbound researchers. Due to the difficulty of making direct measurements during flying and diving, many researchers resort to modeling so as to estimate metabolic rate during each of those activities in the wild, but those models can be inaccurate. Fortunately, the miniaturization, customization and commercialization of biologgers has allowed researchers to increasingly follow animals on their journeys, unravel some of their mysteries and test the accuracy of biomechanical models. I provide a review of the measurement of flying and diving metabolic rate in the wild, paying particular attention to mass loss, doubly-labelled water, heart rate and accelerometry. Biologgers can impact animal behavior and influence the very measurements they are designed to make, and I provide seven guidelines for the ethical use of biologgers. If biologgers are properly applied, quantification of metabolic rate across a range of species could produce robust allometric relationships that could then be generally applied. As measuring flying and diving metabolic rate in captivity is difficult, and often not directly translatable to field conditions, I suggest that applying multiple techniques in the field to reinforce one another may be a viable alternative. The coupling of multi-sensor biologgers with biomechanical modeling promises to improve precision in the measurement of flying and diving metabolic rate in wild animals. Copyright © 2016 Elsevier Inc. All rights reserved.

  6. A no-decompression air dive and ultrasound lung comets.

    Science.gov (United States)

    Dujic, Zeljko; Marinovic, Jasna; Obad, Ante; Ivancev, Vladimir; Breskovic, Toni; Jovovic, Pavle; Ljubkovic, Marko

    2011-01-01

    Increased accumulation of extravascular lung water after repetitive deep trimix dives was recently reported. This effect was evident 40 min post-dive, but in subsequent studies most signs of this lung congestion were not evident 2-3 h post-dive, indicating no major negative effects on respiratory gas exchange following deep dives. Whether this response is unique for trimix dives or also occurs in more frequent air dives is presently unknown. A single no-decompression field dive to 33 m with 20 min bottom time was performed by 12 male divers. Multiple ultrasound lung comets (ULC), bubble grade (BG), and single-breath lung diffusing capacity (DLCO) measurements were made before and up to 120 min after the dive. Median BG was rather high with maximal values observed at 40 min post-dive [median 4 (4-4)]. Arterialization of bubbles from the venous side was observed only in one diver lasting up to 60 min post-dive. Despite high BG, no DCS symptoms were noted. DLCO and ULC were unchanged after the dive at any time point (DLCO(corr) was 33.6 +/- 1.9 ml x min(-1) mmHg(-1) pre-dive, 32.7 +/- 3.8 ml x min(-1) x mmHg(-1) at 60 min post-dive, and 33.2 +/- 5.3 ml x min(-1) x mmHg(-1) at 120 min post-dive; ULC count was 4.1 +/- 1.9 pre-dive, 4.9 +/- 3.3 at 20 min post-dive, and 3.3 +/- 1.9 at 60 min post-dive. These preliminary findings show no evidence of increased accumulation of extravascular lung water in male divers after a single no-decompression air dive at the limits of accepted Norwegian diving tables.

  7. Onboard Acoustic Recording from Diving Elephant Seals

    National Research Council Canada - National Science Library

    Fletcher, Stacia

    1996-01-01

    The aim of this project was to record sounds impinging on free-ranging northern elephant seals, Mirounga angustirostris, a first step in determining the importance of LFS to these animals as they dive...

  8. Facial Baroparesis Caused by Scuba Diving

    Science.gov (United States)

    Kamide, Daisuke; Matsunobu, Takeshi; Shiotani, Akihiro

    2012-01-01

    Middle ear barotrauma is one of the common complications of SCUBA diving representing acute otalgia, hearing loss, and bleeding. But occurrence of facial palsy is rare. Here we report a case of a 30-year-old navy diver suffered middle ear barotrauma with transient facial palsy after SCUBA diving. He felt difficulty in equalizing the pressure in middle ear with Valsalva maneuver during diving, and suffered right facial palsy and aural fullness after diving. Clinical examination showed remarkable bulging of the right tympanic membrane and right facial palsy without other neurological findings. But facial palsy was disappeared immediately after myringotomy. We considered that the etiology of this case was neuropraxia of facial nerve in middle ear caused by over pressure of middle ear. PMID:22953110

  9. Impacts of Artificial Reefs and Diving Tourism

    Directory of Open Access Journals (Sweden)

    Sandra Jakšić

    2013-10-01

    Full Text Available Coral reefs are currently endangered throughout the world. One of the main activities responsible for this is scuba-diving. Scuba-diving on coral reefs was not problematic in the begging, but due to popularization of the new sport, more and more tourists desired to participate in the activity. Mass tourism, direct contact of the tourists with the coral reefs and unprofessional behavior underwater has a negative effect on the coral reefs. The conflict between nature preservation and economy benefits related to scuba-diving tourism resulted in the creation of artificial reefs, used both to promote marine life and as tourists attractions, thereby taking the pressure off the natural coral reefs. Ships, vehicles and other large structures can be found on the coastal sea floor in North America, Australia, Japan and Europe. The concept of artificial reefs as a scuba-diving attraction was developed in Florida. The main goal was to promote aquaculture, with the popularization of scuba-diving attractions being a secondary effect. The aim of this paper is to determine the effects of artificial reefs on scuba-diving tourism, while taking into account the questionnaire carried out among 18 divers

  10. The effect of pre-dive ingestion of dark chocolate on endothelial function after a scuba dive.

    Science.gov (United States)

    Theunissen, Sigrid; Balestra, Costantino; Boutros, Antoine; De Bels, David; Guerrero, François; Germonpré, Peter

    2015-03-01

    The aim of the study was to observe the effects of dark chocolate on endothelial function after scuba diving. Forty-two male scuba divers were divided into two groups: a control (n=21) and a chocolate group (n=21). They performed a 33-metres deep scuba-air dive for 20 minutes in a diving pool (Nemo 33, Brussels). Water temperature was 33⁰C. The chocolate group ingested 30 g of dark chocolate (86% cocoa) 90 minutes before the dive. Flow-mediated dilatation (FMD), digital photoplethysmography and nitric oxide (NO) and peroxynitrites (ONOO-) levels were measured before and after the scuba dive in both groups. A significant decrease in FMD was observed in the control group after the dive (91±7% (mean±95% confidence interval) of pre-dive values; Pchocolate group (105±5% of pre-dive values; Pchocolate group (154±73% of pre-dive values; P=0.04). A significant reduction in ONOO- was observed in the control group (84±12% of pre-dive values; P=0.003) whereas no variation was shown after the dive with chocolate intake (100±28% of pre-dive values; ns). Ingestion of 30 g of dark chocolate 90 minutes before scuba diving prevented post-dive endothelial dysfunction, as the antioxidants contained in dark chocolate probably scavenge free radicals.

  11. Training rats to voluntarily dive underwater: investigations of the mammalian diving response.

    Science.gov (United States)

    McCulloch, Paul F

    2014-11-12

    Underwater submergence produces autonomic changes that are observed in virtually all diving animals. This reflexly-induced response consists of apnea, a parasympathetically-induced bradycardia and a sympathetically-induced alteration of vascular resistance that maintains blood flow to the heart, brain and exercising muscles. While many of the metabolic and cardiorespiratory aspects of the diving response have been studied in marine animals, investigations of the central integrative aspects of this brainstem reflex have been relatively lacking. Because the physiology and neuroanatomy of the rat are well characterized, the rat can be used to help ascertain the central pathways of the mammalian diving response. Detailed instructions are provided on how to train rats to swim and voluntarily dive underwater through a 5 m long Plexiglas maze. Considerations regarding tank design and procedure room requirements are also given. The behavioral training is conducted in such a way as to reduce the stressfulness that could otherwise be associated with forced underwater submergence, thus minimizing activation of central stress pathways. The training procedures are not technically difficult, but they can be time-consuming. Since behavioral training of animals can only provide a model to be used with other experimental techniques, examples of how voluntarily diving rats have been used in conjunction with other physiological and neuroanatomical research techniques, and how the basic training procedures may need to be modified to accommodate these techniques, are also provided. These experiments show that voluntarily diving rats exhibit the same cardiorespiratory changes typically seen in other diving animals. The ease with which rats can be trained to voluntarily dive underwater, and the already available data from rats collected in other neurophysiological studies, makes voluntarily diving rats a good behavioral model to be used in studies investigating the central aspects of the

  12. Statistical correlations and risk analyses techniques for a diving dual phase bubble model and data bank using massively parallel supercomputers.

    Science.gov (United States)

    Wienke, B R; O'Leary, T R

    2008-05-01

    Linking model and data, we detail the LANL diving reduced gradient bubble model (RGBM), dynamical principles, and correlation with data in the LANL Data Bank. Table, profile, and meter risks are obtained from likelihood analysis and quoted for air, nitrox, helitrox no-decompression time limits, repetitive dive tables, and selected mixed gas and repetitive profiles. Application analyses include the EXPLORER decompression meter algorithm, NAUI tables, University of Wisconsin Seafood Diver tables, comparative NAUI, PADI, Oceanic NDLs and repetitive dives, comparative nitrogen and helium mixed gas risks, USS Perry deep rebreather (RB) exploration dive,world record open circuit (OC) dive, and Woodville Karst Plain Project (WKPP) extreme cave exploration profiles. The algorithm has seen extensive and utilitarian application in mixed gas diving, both in recreational and technical sectors, and forms the bases forreleased tables and decompression meters used by scientific, commercial, and research divers. The LANL Data Bank is described, and the methods used to deduce risk are detailed. Risk functions for dissolved gas and bubbles are summarized. Parameters that can be used to estimate profile risk are tallied. To fit data, a modified Levenberg-Marquardt routine is employed with L2 error norm. Appendices sketch the numerical methods, and list reports from field testing for (real) mixed gas diving. A Monte Carlo-like sampling scheme for fast numerical analysis of the data is also detailed, as a coupled variance reduction technique and additional check on the canonical approach to estimating diving risk. The method suggests alternatives to the canonical approach. This work represents a first time correlation effort linking a dynamical bubble model with deep stop data. Supercomputing resources are requisite to connect model and data in application.

  13. Blood oxygen depletion is independent of dive function in a deep diving vertebrate, the northern elephant seal.

    Directory of Open Access Journals (Sweden)

    Jessica U Meir

    Full Text Available Although energetics is fundamental to animal ecology, traditional methods of determining metabolic rate are neither direct nor instantaneous. Recently, continuous blood oxygen (O2 measurements were used to assess energy expenditure in diving elephant seals (Mirounga angustirostris, demonstrating that an exceptional hypoxemic tolerance and exquisite management of blood O2 stores underlie the extraordinary diving capability of this consummate diver. As the detailed relationship of energy expenditure and dive behavior remains unknown, we integrated behavior, ecology, and physiology to characterize the costs of different types of dives of elephant seals. Elephant seal dive profiles were analyzed and O2 utilization was classified according to dive type (overall function of dive: transit, foraging, food processing/rest. This is the first account linking behavior at this level with in vivo blood O2 measurements in an animal freely diving at sea, allowing us to assess patterns of O2 utilization and energy expenditure between various behaviors and activities in an animal in the wild. In routine dives of elephant seals, the blood O2 store was significantly depleted to a similar range irrespective of dive function, suggesting that all dive types have equal costs in terms of blood O2 depletion. Here, we present the first physiological evidence that all dive types have similarly high blood O2 demands, supporting an energy balance strategy achieved by devoting one major task to a given dive, thereby separating dive functions into distinct dive types. This strategy may optimize O2 store utilization and recovery, consequently maximizing time underwater and allowing these animals to take full advantage of their underwater resources. This approach may be important to optimizing energy expenditure throughout a dive bout or at-sea foraging trip and is well suited to the lifestyle of an elephant seal, which spends > 90% of its time at sea submerged making diving its

  14. Knowledge, Attitudes, and Perceptions of FKNMS Dive Operators

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — A total of 69 dive operators in the Florida Keys, representing 77.5% of the region's operator population, provided information on their use of dive and snorkel sites...

  15. 29 CFR 1910.423 - Post-dive procedures.

    Science.gov (United States)

    2010-07-01

    ...-way voice communication system between occupants and a dive team member at the dive location; (iv) A... modes used; (iv) General nature of work performed; (v) Approximate underwater and surface conditions...

  16. Recreational technical diving part 1: an introduction to technical diving methods and activities.

    Science.gov (United States)

    Mitchell, Simon J; Doolette, David J

    2013-06-01

    Technical divers use gases other than air and advanced equipment configurations to conduct dives that are deeper and/or longer than typical recreational air dives. The use of oxygen-nitrogen (nitrox) mixes with oxygen fractions higher than air results in longer no-decompression limits for shallow diving, and faster decompression from deeper dives. For depths beyond the air-diving range, technical divers mix helium, a light non-narcotic gas, with nitrogen and oxygen to produce 'trimix'. These blends are tailored to the depth of intended use with a fraction of oxygen calculated to produce an inspired oxygen partial pressure unlikely to cause cerebral oxygen toxicity and a nitrogen fraction calculated to produce a tolerable degree of nitrogen narcosis. A typical deep technical dive will involve the use of trimix at the target depth with changes to gases containing more oxygen and less inert gas during the decompression. Open-circuit scuba may be used to carry and utilise such gases, but this is very wasteful of expensive helium. There is increasing use of closed-circuit 'rebreather' devices. These recycle expired gas and potentially limit gas consumption to a small amount of inert gas to maintain the volume of the breathing circuit during descent and the amount of oxygen metabolised by the diver. This paper reviews the basic approach to planning and execution of dives using these methods to better inform physicians of the physical demands and risks.

  17. 46 CFR 56.50-110 - Diving support systems.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 2 2010-10-01 2010-10-01 false Diving support systems. 56.50-110 Section 56.50-110... APPURTENANCES Design Requirements Pertaining to Specific Systems § 56.50-110 Diving support systems. (a) In addition to the requirements of this part, piping for diving installations which is permanently installed...

  18. 29 CFR 1926.1085 - Surface-supplied air diving.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Surface-supplied air diving. 1926.1085 Section 1926.1085..., DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Diving Specific Operations Procedures § 1926.1085 Surface-supplied air diving. Note: The requirements applicable to construction work...

  19. 29 CFR 1915.6 - Commerical diving operations.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 7 2010-07-01 2010-07-01 false Commerical diving operations. 1915.6 Section 1915.6 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... Commerical diving operations. Commerical diving operations shall be subject to subpart T of part 1910...

  20. Effects of scuba diving on vascular repair mechanisms.

    Science.gov (United States)

    Culic, Vedrana Cikes; Van Craenenbroeck, Emeline; Muzinic, Nikolina Rezic; Ljubkovic, Marko; Marinovic, Jasna; Conraads, Viviane; Dujic, Zeljko

    2014-01-01

    A single air dive causes transient endothelial dysfunction. Endothelial progenitor cells (EPCs) and circulating angiogenic cells (CAC) contribute synergistically to endothelial repair. In this study (1) the acute effects of diving on EPC numbers and CAC migration and (2) the influence of the gas mixture (air/nitrox-36) was investigated. Ten divers performed two dives to 18 meters on Day (D) 1 and D3, using air. After 15 days, dives were repeated with nitrox-36. Blood sampling took place before and immediately after diving. Circulating EPCs were quantified by flow cytometry, CAC migration of culture was assessed on D7. When diving on air, a trend for reduced EPC numbers is observed post-dive, which is persistent on D1 and D3. CAC migration tends to improve acutely following diving. These effects are more pronounced with nitrox-36 dives. Diving acutely affects EPC numbers and CAC function, and to a larger extent when diving with nitrox-36. The diving-induced oxidative stress may influence recruitment or survival of EPC. The functional improvement of CAC could be a compensatory mechanism to maintain endothelial homeostasis.

  1. Pre-dive vibration effect on bubble formation after a 30-m dive requiring a decompression stop.

    Science.gov (United States)

    Germonpré, Peter; Pontier, Jean-Michel; Gempp, Emmanuel; Blatteau, Jean-Eric; Deneweth, Stefaan; Lafère, Pierre; Marroni, Alessandro; Balestra, Costantino

    2009-12-01

    The preconditioning of divers to reduce post-dive decompression sickness (DCS) has gained increased interest in diving medical research over the last few years. The beneficial effects of physical exercise, oxygen breathing, hyperbaric exposure, heat exposure, hyperhydration, or nitroglycerin administration before the dive are only a few examples of ongoing research. In this work, we investigated the effects of pre-dive whole-body vibration on post-dive bubble formation. Following French Navy standard dive procedures, 14 healthy male military divers performed 2 identical dives 1 wk apart to 30 m of seawater (msw) for 30 min. One of the dives was randomly preceded by a 30-min whole-body vibration session (frequencies 35-40 Hz) 1 h before the dive. Post-dive bubbles were measured precordially 30, 60, and 90 min after the dive and were graded according to the Kissman Integrated Severity Score (KISS) protocol, with and without knee flexing. Arterial endothelial function was measured before and after vibration using flow mediated dilation (FMD) measurement. A significant reduction in bubble scores was observed after the "vibration" dive. As there was no observed change in FMD after vibration, we do not believe a nitric oxide mediated mechanism is involved; rather, a mechanical dislodgement or enhanced lymphatic elimination of gas nuclei is hypothesized.

  2. A Navy Diving Supervisor's Guide to the Nontechnical Skills Required for Safe and Productive Diving Operations

    National Research Council Canada - National Science Library

    O'Connor, Paul E

    2005-01-01

    Although the diving community is proficient in identifying and mitigating technical problems, it is not as adept in recognizing and reducing the nontechnical human factors errors that cause accidents...

  3. The dive response redefined: underwater behavior influences cardiac variability in freely diving dolphins.

    Science.gov (United States)

    Noren, Shawn R; Kendall, Traci; Cuccurullo, Veronica; Williams, Terrie M

    2012-08-15

    A hallmark of the dive response, bradycardia, promotes the conservation of onboard oxygen stores and enables marine mammals to submerge for prolonged periods. A paradox exists when marine mammals are foraging underwater because activity should promote an elevation in heart rate (f(H)) to support increased metabolic demands. To assess the effect of the interaction between the diving response and underwater activity on f(H), we integrated interbeat f(H) with behavioral observations of adult bottlenose dolphins diving and swimming along the coast of the Bahamas. As expected for the dive response, f(H) while resting during submergence (40±6 beats min(-1)) was significantly lower than f(H) while resting at the water surface (105±8 beats min(-1)). The maximum recorded f(H) (f(H,max)) was 128±7 beats min(-1), and occurred during post-dive surface intervals. During submergence, the level of bradycardia was modified by activity. Behaviors such as simple head bobbing at depth increased f(H) by 40% from submerged resting levels. Higher heart rates were observed for horizontal swimming at depth. Indeed, the dolphins operated at 37-58% of their f(H,max) while active at depth and approached 57-79% of their f(H,max) during anticipatory tachycardia as the animals glided to the surface. f(H) was significantly correlated with stroke frequency (range=0-2.5 strokes s(-1), r=0.88, N=25 dives) and calculated swim speed (range=0-5.4 m s(-1), r=0.88, N=25 dives). We find that rather than a static reflex, the dive response is modulated by behavior and exercise in a predictable manner.

  4. Negative neurofunctional effects of frequency, depth and environment in recreational scuba diving: the Geneva "memory dive" study.

    Science.gov (United States)

    Slosman, D O; De Ribaupierre, S; Chicherio, C; Ludwig, C; Montandon, M-L; Allaoua, M; Genton, L; Pichard, C; Grousset, A; Mayer, E; Annoni, J-M; De Ribaupierre, A

    2004-04-01

    To explore relationships between scuba diving activity, brain, and behaviour, and more specifically between global cerebral blood flow (CBF) or cognitive performance and total, annual, or last 6 months' frequencies, for standard dives or dives performed below 40 m, in cold water or warm sea geographical environments. A prospective cohort study was used to examine divers from diving clubs around Lac Léman and Geneva University Hospital. The subjects were 215 healthy recreational divers (diving with self-contained underwater breathing apparatus). Main outcome measures were: measurement of global CBF by (133)Xe SPECT (single photon emission computed tomography); psychometric and neuropsychological tests to assess perceptual-motor abilities, spatial discrimination, attentional resources, executive functioning, and memory; evaluation of scuba diving activity by questionnaire focusing on number and maximum depth of dives and geographical site of the diving activity (cold water v warm water); and body composition analyses (BMI). (1) A negative influence of depth of dives on CBF and its combined effect with BMI and age was found. (2) A specific diving environment (more than 80% of dives in lakes) had a negative effect on CBF. (3) Depth and number of dives had a negative influence on cognitive performance (speed, flexibility and inhibition processing in attentional tasks). (4) A negative effect of a specific diving environment on cognitive performance (flexibility and inhibition components) was found. Scuba diving may have long-term negative neurofunctional effects when performed in extreme conditions, namely cold water, with more than 100 dives per year, and maximal depth below 40 m.

  5. Oxidative stress in breath-hold divers after repetitive dives.

    Science.gov (United States)

    Theunissen, Sigrid; Sponsiello, Nicola; Rozloznik, Miroslav; Germonpré, Peter; Guerrero, François; Cialoni, Danilo; Balestra, Constantino

    2013-06-01

    Hyperoxia causes oxidative stress. Breath-hold diving is associated with transient hyperoxia followed by hypoxia and a build-up of carbon dioxide (CO₂), chest-wall compression and significant haemodynamic changes. This study analyses variations in plasma oxidative stress markers after a series of repetitive breath-hold dives. Thirteen breath-hold divers were asked to perform repetitive breath-hold dives to 20 metres' depth to a cumulative breath-hold time of approximately 20 minutes over an hour in the open sea. Plasma nitric oxide (NO), peroxinitrites (ONOO⁻) and thiols (R-SH) were measured before and after the dive sequence. Circulating NO significantly increased after successive breath-hold dives (169.1 ± 58.26% of pre-dive values; P = 0.0002). Peroxinitrites doubled after the dives (207.2 ± 78.31% of pre-dive values; P = 0.0012). Thiols were significantly reduced (69.88 ± 19.23% of pre-dive values; P = 0.0002). NO may be produced by physical effort during breath-hold diving. Physical exercise, the transient hyperoxia followed by hypoxia and CO₂ accumulation would all contribute to the increased levels of superoxide anions (O₂²⁻). Since interaction of O₂²⁻ with NO forms ONOO⁻, this reaction is favoured and the production of thiol groups is reduced. Oxidative stress is, thus, present in breath-hold diving.

  6. Estimating the risk of a scuba diving fatality in Australia.

    Science.gov (United States)

    Lippmann, John; Stevenson, Christopher; McD Taylor, David; Williams, Jo

    2016-12-01

    There are few data available on which to estimate the risk of death for Australian divers. This report estimates the risk of a scuba diving fatality for Australian residents, international tourists diving in Queensland, and clients of a large Victorian dive operator. Numerators for the estimates were obtained from the Divers Alert Network Asia-Pacific dive fatality database. Denominators were derived from three sources: Participation in Exercise, Recreation and Sport Surveys, 2001-2010 (Australian resident diving activity data); Tourism Research Australia surveys of international visitors to Queensland 2006-2014 and a dive operator in Victoria 2007-2014. Annual fatality rates (AFR) and 95% confidence intervals (95% CI) were calculated using an exact binomial test. Estimated AFRs were: 0.48 (0.37-0.59) deaths per 100,000 dives, or 8.73 (6.85-10.96) deaths per 100,000 divers for Australian residents; 0.12 (0.05-0.25) deaths per 100,000 dives, or 0.46 (0.20-0.91) deaths per 100,000 divers for international visitors to Queensland; and 1.64 (0.20-5.93) deaths per 100,000 dives for the dive operator in Victoria. On a per diver basis, Australian residents are estimated to be almost twenty times more likely to die whilst scuba diving than are international visitors to Queensland, or to lower than fourfold on a per dive basis. On a per dive basis, divers in Victoria are fourteen times more likely to die than are Queensland international tourists. Although some of the estimates are based on potentially unreliable denominator data extrapolated from surveys, the diving fatality rates in Australia appear to vary by State, being considerably lower in Queensland than in Victoria. These estimates are similar to or lower than comparable overseas estimates, although reliability of all such measurements varies with study size and accuracy of the data available.

  7. Computer validation and statistical correlations of a modern decompression diving algorithm.

    Science.gov (United States)

    Wienke, B R

    2010-03-01

    A diving algorithm is a safe combination of model and data to efficiently stage diver ascents following arbitrary underwater exposures. To that end, we detail a modern one, the LANL reduced gradient bubble model (RGBM), dynamical principles, and correlations with the LANL Data Bank data. Table, profile, and meter fit and risk parameters are obtained in statistical likelihood analysis from decompression exposure data. The RGBM algorithm enjoys extensive and utilitarian application in mixed gas diving, both in recreational and technical sectors, and forms the bases for released tables, software, and decompression meters used by scientific, commercial, and research divers. The LANL Data Bank is described, and the methods used to deduce risk are detailed. Risk functions for dissolved gas and bubbles are summarized. Parameters that can be used to estimate profile risk are tallied. To fit data, a modified Levenberg-Marquardt routine is employed. The LANL Data Bank presently contains 2879 profiles with 20 cases of DCS across nitrox, trimix, and heliox deep and decompression diving. This work establishes needed correlation between global mixed gas diving, specific bubble model, and deep stop data. Our objective is operational diving, not clinical science. The fit of bubble model to deep stop data is chi squared significant to 93%, using the logarithmic likelihood ratio of null set (actual set) to fit set. The RGBM algorithm is thus validated within the LANL Data Bank. Extensive and safe utilization of the model reported in field user statistics for tables, meters, and software also suggests real world validation, that is, one without noted nor reported DCS spikes in the field. Copyright (c) 2009 Elsevier Ltd. All rights reserved.

  8. [Hyperbaric therapy and diving medicine - diving medicine - present state and prospects].

    Science.gov (United States)

    Winkler, Bernd; Muth, Claus-Martin; Piepho, Tim

    2015-10-01

    The diving accident (decompression incident, DCI) occurs in the decompression phase of dives. The DCI can either be caused by an arterial gas embolism (AGE) subsequent to a pulmonary barotrauma or by the formation of inert gas bubbles subsequent to a reduction of ambient pressure during the ascent from depth. In contrast to the traditional assumption that decompression incidents only occur if decompression rules are neglected, recent data indicate that a vast amount of diving accidents occur even though divers adhered to the rules. Hence, there is a large inter- and intraindividual variability in the predisposition for diving accidents. Within the past few years, the molecular understanding of the pathophysiology of diving accidents has improved considerably. It is now well accepted that pro-inflammatory and pro-coagulatory mechanisms play a central role. Moreover, microparticles are increasingly discussed in the pathogenesis of diving accidents. These new molecular findings have not yet resulted in new therapeutic approaches. However, new approaches of preconditioning before the dive have been developed which are intended to reduce the risk of diving accidents. The symptoms of a diving accident show a large variability and range. They reach from pruritus over tension in the female breast, marbled skin and pain in the joints to severe neurological disability like paraplegia or hemiplegia. Furthermore, pulmonary symptoms can be a result of a pulmonary gas embolism and/or a tension pneumothorax. Extreme cases can also manifest as generalized, difficult-to-treat seizures, loss of consciousness or even death. The evidence-based therapy of diving accidents consists of an immediate application of 100% inspiratory O2. This can be performed via a demand valve, face mask with reservoir bag or ventilation bag connected to a reservoir bag. Fluid substitution is performed by i. v. infusion of 500-1000ml/h of cristalloids. If consciousness is not impaired, the diver is

  9. Exercise intensity inferred from air consumption during recreational scuba diving.

    Science.gov (United States)

    Buzzacott, Peter; Pollock, Neal W; Rosenberg, Michael

    2014-06-01

    Episodic exercise is a risk factor for acute cardiac events and cardiac complications are increasingly recognized in fatalities during recreational scuba diving. What is not known is the exercise intensity involved in typical recreational diving. This study used pre- to post-dive gas cylinder pressure drop to estimate air consumption and, from that, exercise intensity during recreational dives. Dive profiles were captured electronically and divers self-reported cylinder pressure changes, perceived workload, thermal status and any problems during dives. Mean surface air consumption (SAC) rate per kg body weight and mean exercise intensity (reported in metabolic equivalents, MET multiples of assumed resting metabolic rate of 3.5 mL·kg⁻¹·min⁻¹) were then estimated. Data are reported as mean ± standard deviation. A total of 959 recreational air dives (20 ± 9 metres' sea water maximum depth; 50 ± 12 min underwater time) by 139 divers (42 ± 10 y age; 11 ± 10 y of diving; 12% smokers; 73% male) were monitored. Problems were reported with 129/959 dives: buoyancy (45%), equalization (38%), rapid ascent (10%), vertigo (5%) and other (2%). Assuming a 10% overestimate due to cylinder cooling and uncontrolled gas loss, the estimated exercise intensity associated with monitored dives was 5 ± 1 MET. Mean ± 2SD, or 7 MET, captures the effort associated with the vast majority of dives monitored. Our estimates suggest that uncomplicated recreational dives require moderate-intensity energy expenditure to complete, with a 7-MET capacity generally adequate. Higher levels of aerobic fitness are still strongly recommended to ensure ample reserves. Further research is needed to quantify energetic demands of recreational diving during both typical and emergent events in both experienced and less experienced divers.

  10. The diving behavior of blue and fin whales: is dive duration shorter than expected based on oxygen stores?

    Science.gov (United States)

    Croll, D A; Acevedo-Gutiérrez, A; Tershy, B R; Urbán-Ramírez, J

    2001-07-01

    Many diving seabirds and marine mammals have been found to regularly exceed their theoretical aerobic dive limit (TADL). No animals have been found to dive for durations that are consistently shorter than their TADL. We attached time-depth recorders to 7 blue whales and 15 fin whales (family Balaenopteridae). The diving behavior of both species was similar, and we distinguished between foraging and traveling dives. Foraging dives in both species were deeper, longer in duration and distinguished by a series of vertical excursions where lunge feeding presumably occurred. Foraging blue whales lunged 2.4 (+/-1.13) times per dive, with a maximum of six times and average vertical excursion of 30.2 (+/-10.04) m. Foraging fin whales lunged 1.7 (+/-0.88) times per dive, with a maximum of eight times and average vertical excursion of 21.2 (+/-4.35) m. The maximum rate of ascent of lunges was higher than the maximum rate of descent in both species, indicating that feeding lunges occurred on ascent. Foraging dives were deeper and longer than non-feeding dives in both species. On average, blue whales dived to 140.0 (+/-46.01) m and 7.8 (+/-1.89) min when foraging, and 67.6 (+/-51.46) m and 4.9 (+/-2.53) min when not foraging. Fin whales dived to 97.9 (+/-32.59) m and 6.3 (+/-1.53) min when foraging and to 59.3 (+/-29.67) m and 4.2 (+/-1.67) min when not foraging. The longest dives recorded for both species, 14.7 min for blue whales and 16.9 min for fin whales, were considerably shorter than the TADL of 31.2 and 28.6 min, respectively. An allometric comparison of seven families diving to an average depth of 80-150 m showed a significant relationship between body mass and dive duration once Balaenopteridae whales, with a mean dive duration of 6.8 min, were excluded from the analysis. Thus, the short dive durations of blue whales and fin whales cannot be explained by the shallow distribution of their prey. We propose instead that short duration diving in large whales results from

  11. Thermal comfort of diving dry suit with the use of the warp-knitted fabric

    Science.gov (United States)

    Lenfeldova, I.; Hes, L.; Annayeva, M.

    2016-07-01

    Achievement of a good level of thermal comfort of under-suits for dry suit diving which enable also the required mobility of the diver in water is inevitable not only for the scuba sport and commercial diving people but also for safety and activities of people who make research under water. The aim of this work is to verify whether selected knitted structures (which are not waterproof) can substitute the currently used textile materials (nonwovens). This dry-suit innovation is intended to increase the properties which correspond to the perception of thermal comfort of the diver in water. To achieve this objective, the Alambeta thermal tester was used in the study for experimental determination of thermal resistance of spacer warp knitted fabric at varying contact pressure. The studied textiles were expected to be very suitable for the intended application due to their low compressibility which yields relatively high thickness a hence increased thermal insulation.

  12. Deadly diving? Physiological and behavioural management of decompression stress in diving mammals

    Science.gov (United States)

    Hooker, S. K.; Fahlman, A.; Moore, M. J.; Aguilar de Soto, N.; Bernaldo de Quirós, Y.; Brubakk, A. O.; Costa, D. P.; Costidis, A. M.; Dennison, S.; Falke, K. J.; Fernandez, A.; Ferrigno, M.; Fitz-Clarke, J. R.; Garner, M. M.; Houser, D. S.; Jepson, P. D.; Ketten, D. R.; Kvadsheim, P. H.; Madsen, P. T.; Pollock, N. W.; Rotstein, D. S.; Rowles, T. K.; Simmons, S. E.; Van Bonn, W.; Weathersby, P. K.; Weise, M. J.; Williams, T. M.; Tyack, P. L.

    2012-01-01

    Decompression sickness (DCS; ‘the bends’) is a disease associated with gas uptake at pressure. The basic pathology and cause are relatively well known to human divers. Breath-hold diving marine mammals were thought to be relatively immune to DCS owing to multiple anatomical, physiological and behavioural adaptations that reduce nitrogen gas (N2) loading during dives. However, recent observations have shown that gas bubbles may form and tissue injury may occur in marine mammals under certain circumstances. Gas kinetic models based on measured time-depth profiles further suggest the potential occurrence of high blood and tissue N2 tensions. We review evidence for gas-bubble incidence in marine mammal tissues and discuss the theory behind gas loading and bubble formation. We suggest that diving mammals vary their physiological responses according to multiple stressors, and that the perspective on marine mammal diving physiology should change from simply minimizing N2 loading to management of the N2 load. This suggests several avenues for further study, ranging from the effects of gas bubbles at molecular, cellular and organ function levels, to comparative studies relating the presence/absence of gas bubbles to diving behaviour. Technological advances in imaging and remote instrumentation are likely to advance this field in coming years. PMID:22189402

  13. Diving dentistry: a review of the dental implications of scuba diving.

    Science.gov (United States)

    Zadik, Y; Drucker, S

    2011-09-01

    In light of the overwhelming popularity of self-contained underwater breathing apparatus (SCUBA) diving, general dental practitioners should be prepared to address complications arising as a result of diving and to provide patients with accurate information. The aim of this article was to introduce the concepts of diving medicine and dentistry to the dentist, and to supply the dental practitioner with some diagnostic tools as well as treatment guidelines. The literature was reviewed to address diving barotrauma (pressure-induced injury related to an air space) to the head, face and oral regions, as well as scuba mouthpiece-related oral conditions. The relevant conditions for dentists who treat divers include diving-associated headache (migraine, tension-type headache), barosinusitis and barotitis-media (sinus and middle ear barotrauma, respectively), neuropathy, trigeminal (CN V) or facial (CN VII) nerve baroparesis (pressure-induced palsy), dental barotrauma (barometric-related tooth injury), barodontalgia (barometric-related dental pain), mouthpiece-associated herpes infection, pharyngeal gag reflex and temporomandibular joint disorder (dysfunction). For each condition, a theoretical description is followed by practical recommendations for the dental practitioner for the prevention and management of the condition. © 2011 Australian Dental Association.

  14. Sudden infant death triggered by dive reflex

    Science.gov (United States)

    Matturri, L; Ottaviani, G; Lavezzi, A M

    2005-01-01

    The dive reflex is the reflex mechanism most frequently considered in the aetiopathogenesis of sudden infant death syndrome (SIDS). This seems to persist in human beings as an inheritance from diver birds and amphibians. It has been reported that washing the face with cold water or plunging into cold water can provoke cardiac deceleration through the intervention of the ambiguus and the vagal dorsal nuclei. This report describes a case of SIDS that offers a unique insight into the role of the dive reflex in determining a lethal outcome. Examination of the brainstem on serial sections revealed severe bilateral hypoplasia of the arcuate nucleus and gliosis of the other cardiorespiratory medullary nuclei. The coronary and cardiac conduction arteries presented early atherosclerotic lesions. The possible role of parental cigarette smoking in the pathogenesis of arcuate nucleus hypoplasia and early coronary atherosclerotic lesions is also discussed. PMID:15623488

  15. TEMPOROMANDIBULAR DISORDERS IN SCUBA DIVERS DURING DIVING CERTIFICATION TRAINING PROGRAMME

    OpenAIRE

    ÖZTÜRK, Özmen; Tek, Mustafa; Seven, Hüseyin

    2013-01-01

    Objective: The design of a diving regulator's mouth-piece is known to increase the risk of a temporomandibular disorder (TMD) in SCUBA divers. The total weight of a diving regulator is reflected directly on the temporomandibular joint (TMJ) causing articular and periarticular problems. In this study, the prevalence of TMD in SCUBA divers having a training for diving certification is investigated. We also aimed to determine the factors that lead to TMD, and clarify the observation that there i...

  16. Diving response in rats: role of the subthalamic vasodilator area.

    OpenAIRE

    Eugene Golanov; Shiflett, James M.; Britz, Gavin W.

    2016-01-01

    Diving response is a powerful integrative response targeted toward survival of the hypoxic/anoxic conditions. Being present in all animals and humans it allows to survive adverse conditions like diving. Earlier we discovered that forehead stimulation affords neuroprotective effect decreasing infarction volume triggered by permanent occlusion of the middle cerebral artery in rats. We hypothesized that cold stimulation of the forehead induces diving response in rats, which, in turn, exerts neur...

  17. Diving accidents: a cohort study from the Netherlands

    OpenAIRE

    Smithuis, J. W.; Gips, E.; van Rees Vellinga, T. P.; Gaakeer, M.I.

    2016-01-01

    Background Diving is, besides professional reasons, an increasingly popular leisure activity. Whilst statistically compared to other sports safe, diving accidents can result in serious complications. In order to treat this specific patient category adequately, early diagnosis is important. In this study, we explore various medical aspects of diving accidents. By sharing our experiences, we intend to create awareness and enhance urgent medical care for this specific category of patients. Metho...

  18. Scuba diving post-bleomycin therapy: a case report.

    Science.gov (United States)

    Gray, Richard N

    2010-01-01

    Though there are theoretical risks to scuba diving after undergoing chemotherapy with bleomycin, this case report demonstrates that it may be done without obvious injury if one takes adequate precautions. In this case, one year was allowed to elapse prior to a return to diving. Subsequently 52 dives have been accomplished with no observable adverse effects. Studies are recommended to determine what precautions should be instituted.

  19. Diving-Flight Aerodynamics of a Peregrine Falcon (Falco peregrinus)

    OpenAIRE

    Ponitz, Benjamin; Schmitz, Anke; Fischer, Dominik; Bleckmann, Horst; Brücker, Christoph

    2014-01-01

    This study investigates the aerodynamics of the falcon Falco peregrinus while diving. During a dive peregrines can reach velocities of more than 320 km h⁻¹. Unfortunately, in freely roaming falcons, these high velocities prohibit a precise determination of flight parameters such as velocity and acceleration as well as body shape and wing contour. Therefore, individual F. peregrinus were trained to dive in front of a vertical dam with a height of 60 m. The presence of a well-defined background...

  20. Oxidative stress in breath-hold divers after repetitive dives

    OpenAIRE

    Theunissen, S; Sponsiello, N; Rozloznik, M; Germonpre, P.; Guerrero, F.; Cialoni, D; Balestra, C.

    2013-01-01

    Introduction: Hyperoxia causes oxidative stress. Breath-hold diving is associated with transient hyperoxia followed by hypoxia and a build-up of carbon dioxide (CO2), chest-wall compression and significant haemodynamic changes. This study analyses variations in plasma oxidative stress markers after a series of repetitive breath-hold dives.Methods: Thirteen breath-hold divers were asked to perform repetitive breath-hold dives to 20 metres’ depth to a cumulative breath-hold time of approximatel...

  1. Diving costs as a component of daily energy budgets of aquatic birds and mammals : Generalizing the inclusion of dive-recovery costs demonstrated in tufted ducks

    NARCIS (Netherlands)

    deLeeuw, JJ

    1996-01-01

    Metabolic studies on freely diving birds and mammals are reviewed and allometric relations of diving costs are presented. A distinction can be made between three different types of diving costs: (1) metabolic rate during submergence, relevant in estimating aerobic dive limits, (2) average metabolic

  2. [Scuba diving in children: Physiology, risks and recommendations].

    Science.gov (United States)

    Cilveti, R; Osona, B; Peña, J A; Moreno, L; Asensio, O

    2015-12-01

    The increase in recreational scuba diving in recent years, including children, involves risks and the possibility of accidents. While legislation, conditions and risks of scuba diving are well documented in adults, scientific evidence in scuba diving by children and adolescents is sparse and isolated. Furthermore, existing guidelines and recommendations for adults cannot be transferred directly to children. These circumstances have led to the Group on Techniques of the Spanish Society of Pediatric Pulmonology (SENP) to perform a literature search to review and update the knowledge about scuba diving in children. Physiological adaptations of the body are examined during the dive, as well as the anatomical and physiological characteristics of children that should be taken into account in scuba diving. The most common types of accidents and its causes, as well as the risks of scuba diving practice in children with previous diseases are discussed, along with details of the medical and psychological requirements for scuba diving to be considered in the assessment of child and adolescent. A list of recommendations for scuba diving with compressed air in children is presented by a group of experts. Copyright © 2015 Asociación Española de Pediatría. Published by Elsevier España, S.L.U. All rights reserved.

  3. Gait switches in deep-diving beaked whales: biomechanical strategies for long-duration dives.

    Science.gov (United States)

    Martín López, Lucía Martina; Miller, Patrick J O; Aguilar de Soto, Natacha; Johnson, Mark

    2015-05-01

    Diving animals modulate their swimming gaits to promote locomotor efficiency and so enable longer, more productive dives. Beaked whales perform extremely long and deep foraging dives that probably exceed aerobic capacities for some species. Here, we use biomechanical data from suction-cup tags attached to three species of beaked whales (Mesoplodon densirostris, N=10; Ziphius cavirostris, N=9; and Hyperoodon ampullatus, N=2) to characterize their swimming gaits. In addition to continuous stroking and stroke-and-glide gaits described for other diving mammals, all whales produced occasional fluke-strokes with distinctly larger dorso-ventral acceleration, which we termed 'type-B' strokes. These high-power strokes occurred almost exclusively during deep dive ascents as part of a novel mixed gait. To quantify body rotations and specific acceleration generated during strokes we adapted a kinematic method combining data from two sensors in the tag. Body rotations estimated with high-rate magnetometer data were subtracted from accelerometer data to estimate the resulting surge and heave accelerations. Using this method, we show that stroke duration, rotation angle and acceleration were bi-modal for these species, with B-strokes having 76% of the duration, 52% larger body rotation and four times more surge than normal strokes. The additional acceleration of B-strokes did not lead to faster ascents, but rather enabled brief glides, which may improve the overall efficiency of this gait. Their occurrence towards the end of long dives leads us to propose that B-strokes may recruit fast-twitch fibres that comprise ∼80% of swimming muscles in Blainville's beaked whales, thus prolonging foraging time at depth. © 2015. Published by The Company of Biologists Ltd.

  4. 7 CFR 1000.19 - Commercial food processing establishment.

    Science.gov (United States)

    2010-01-01

    ... MARKETING SERVICE (Marketing Agreements and Orders; Milk), DEPARTMENT OF AGRICULTURE GENERAL PROVISIONS OF FEDERAL MILK MARKETING ORDERS Definitions § 1000.19 Commercial food processing establishment. Commercial...

  5. Using "Technical Diving" Techniques for Short Dives in the 80-100 MSW Range

    Science.gov (United States)

    2001-06-01

    adequate thermal protection, and appropriate redundancy. A typical dive to 80 msw for 20 min could use for the bottom mix a " trimix " of about 17...34 trimix " are regarded as being considerably safer than making equivalent dives with air as the breathing gas, because this avoids the narcosis in the...to relieve the narcosis, resulting in a " trimix " of oxygen, helium, and nitrogen The reason such mixes had not been used before was that there had been

  6. Provisions distributed

    NARCIS (Netherlands)

    Martin Olsthoorn; Evert Pommer; Michiel Ras; Ab van der Torre; Jean Marie Wildeboer Schut

    2017-01-01

    Original title: Voorzieningen verdeeld Citizens ‘profit’ from the government when they receive income support because they are unable to generate an income themselves. They also profit when they make use of provisions such as care, support, education, public transport, sport, culture

  7. Diving through the thermal window: implications for a warming world

    Science.gov (United States)

    Campbell, Hamish A.; Dwyer, Ross G.; Gordos, Matthew; Franklin, Craig E.

    2010-01-01

    Population decline and a shift in the geographical distribution of some ectothermic animals have been attributed to climatic warming. Here, we show that rises in water temperature of a few degrees, while within the thermal window for locomotor performance, may be detrimental to diving behaviour in air-breathing ectotherms (turtles, crocodilians, marine iguanas, amphibians, snakes and lizards). Submergence times and internal and external body temperature were remotely recorded from freshwater crocodiles (Crocodylus johnstoni) while they free-ranged throughout their natural habitat in summer and winter. During summer, the crocodiles' mean body temperature was 5.2 ± 0.1°C higher than in winter and the largest proportion of total dive time was composed of dive durations approximately 15 min less than in winter. Diving beyond 40 min during summer required the crocodiles to exponentially increase the time they spent on the surface after the dive, presumably to clear anaerobic debt. The relationship was not as significant in winter, even though a greater proportion of dives were of a longer duration, suggesting that diving lactate threshold (DLT) was reduced in summer compared with winter. Additional evidence for a reduced DLT in summer was derived from the stronger influence body mass exerted upon dive duration, compared to winter. The results demonstrate that the higher summer body temperature increased oxygen demand during the dive, implying that thermal acclimatization of the diving metabolic rate was inadequate. If the study findings are common among air-breathing diving ectotherms, then long-term warming of the aquatic environment may be detrimental to behavioural function and survivorship. PMID:20610433

  8. Effect of recreational diving on Patagonian rocky reefs.

    Science.gov (United States)

    Bravo, Gonzalo; Márquez, Federico; Marzinelli, Ezequiel M; Mendez, María M; Bigatti, Gregorio

    2015-03-01

    Tourism has grown considerably in the last decades, promoting activities such as recreational SCUBA diving that may affect marine benthic communities. In Puerto Madryn, Patagonia Argentina, sub-aquatic tourism areas (STA) receive about 7,000 divers per year. Diving is concentrated on a few small rocky reefs and 50% of the dives occur in summer. In this work, we evaluated the effect of recreational diving activities on benthic communities and determined whether diving causes a press (long-term) or a pulse (short-term) response. We quantified the percentage cover of benthic organisms and compared benthic assemblage structure and composition between two sites with contrasting usage by divers, 'highly disturbed' and 'moderately disturbed' sites, and two 'control' sites with similar physical characteristics but no diving activity, twice before and after the diving peak in summer. We found differences in benthic assemblage structure (identity and relative abundance of taxa) and composition (identity only) among diving sites and controls. These differences were consistent before and after the peak of diving in summer, suggesting that recreational diving may produce a press impact on overall benthic assemblage structure and composition in these STA. At the moderately disturbed site, however, covers of specific taxa, such as some key habitat-forming or highly abundant species, usually differed from those in controls only immediately after summer, after which they begun to resemble controls, suggesting a pulse impact. Thus, STA in Golfo Nuevo seem to respond differently to disturbances of diving depending on the usage of the sites. This information is necessary to develop sound management strategies in order to preserve local biodiversity. Copyright © 2014 Elsevier Ltd. All rights reserved.

  9. To dive or not to dive with bleomycin: a practical algorithm

    NARCIS (Netherlands)

    van Hulst, Robert A.; Rietbroek, Ronald C.; Gaastra, Menno T. W.; Schlösser, Noel J. J.

    2011-01-01

    Bleomycin is used in the treatment of different cancers, but possible side effects of interstitial pneumonitis and fibrosis are associated with increased concentrations of oxygen. Therefore, clinicians are reluctant to declare young people fit for scuba diving after bleomycin treatment, because

  10. Recent modifications to the investigation of diving related deaths.

    Science.gov (United States)

    Edmonds, Carl; Caruso, James

    2014-03-01

    The investigation of deaths that involve diving using a compressed breathing gas (SCUBA diving) is a specialized area of forensic pathology. Diving related deaths occur more frequently in certain jurisdictions, but any medical examiner or coroner's office may be faced with performing this type of investigation. In order to arrive at the correct conclusion regarding the cause and manner of death, forensic pathologists and investigators need to have a basic understanding of diving physiology, and should also utilize more recently developed technology and ancillary techniques. In the majority of diving related deaths, the cause of death is drowning, but this more often represents a final common pathway due to a water environment. The chain of events leading to the death is just as important to elucidate if similar deaths are to be minimized in the future. Re-enactment of accident scenarios, interrogation of dive computers, postmortem radiographic imaging, and slight alterations in autopsy technique may allow some of these diving related deaths to the better characterized. The amount and location of gas present in the body at the time of autopsy may be very meaningful or may simply represent a postmortem artifact. Medical examiners, coroners, and forensic investigators should consider employing select ancillary techniques to more thoroughly investigate the factors contributing a death associated with SCUBA diving.

  11. Scuba Diving and Kinesiology: Development of an Academic Program

    Science.gov (United States)

    Kovacs, Christopher R.; Walter, Daniel

    2015-01-01

    The use of scuba diving as a recreational activity within traditional university instructional programs has been well established. Departments focusing on kinesiology, physical education, or exercise science have often provided scuba diving lessons as part of their activity-based course offerings. However, few departments have developed an…

  12. Swimming & Diving: Special Olympics Sports Skills Instructional Program.

    Science.gov (United States)

    Joseph P. Kennedy, Jr. Foundation, Washington, DC.

    One of five parts of the Special Olympics' Sports Skills Instructional Program, the booklet addresses ways to teach swimming and diving to mentally retarded students. Short term objectives of the program encompass warmup, basic swimming and diving skills, safety, and good sportsmanship. The long term goal focuses on acquisition of basic skills,…

  13. 50 CFR 640.22 - Gear and diving restrictions.

    Science.gov (United States)

    2010-10-01

    ... 50 Wildlife and Fisheries 8 2010-10-01 2010-10-01 false Gear and diving restrictions. 640.22 Section 640.22 Wildlife and Fisheries FISHERY CONSERVATION AND MANAGEMENT, NATIONAL OCEANIC AND... ATLANTIC Management Measures § 640.22 Gear and diving restrictions. (a) Prohibited gear and methods. (1) A...

  14. Socio-economic aspects of the Sodwana Bay SCUBA diving ...

    African Journals Online (AJOL)

    Understanding socio-economic aspects of the diving industry at Sodwana Bay, including data on participant motivation and expenditure, is crucial for the effective management of the St Lucia and Maputaland marine protected areas, South Africa. Between July 2011 and July 2012 a total of 59 553 dives was conducted by ...

  15. Danish diving-related fatalities 1999-2012

    DEFF Research Database (Denmark)

    Vinkel, Julie; Bak, Peter; Hyldegaard, Ole

    2016-01-01

    AIM: The purpose was to explore causative tendencies among diving fatalities to prevent similar injuries in the future. METHODS: We report 33 fatal diving injuries that occurred among Danish divers during the period 1999-2012 in Scandinavian waters. The study was performed as a retrospective...

  16. 29 CFR 1926.1086 - Mixed-gas diving.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Mixed-gas diving. 1926.1086 Section 1926.1086 Labor Regulations Relating to Labor (Continued) OCCUPATIONAL SAFETY AND HEALTH ADMINISTRATION, DEPARTMENT OF LABOR... Mixed-gas diving. Note: The requirements applicable to construction work under this section are...

  17. 29 CFR 1910.425 - Surface-supplied air diving.

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 5 2010-07-01 2010-07-01 false Surface-supplied air diving. 1910.425 Section 1910.425... Procedures § 1910.425 Surface-supplied air diving. (a) General. Employers engaged in surface-supplied air... shall be available while a diver is in the water; (iii) A diver-carried reserve breathing gas supply...

  18. Effects of wetland management on carrying capacity of diving ducks and shorebirds in a coastal estuary

    Science.gov (United States)

    Brand, Arianna L.; Takekawa, John; Shinn, Joel; Graham, Tanya R.; Buffington, Kevin J.; Gustafson, K. Ben; Smith, Lacy M.; Spring, Sarah E.; Miles, A. Keith

    2014-01-01

    With global loss of natural wetlands, managed wetlands increasingly support energy requirements for wintering shorebirds and waterfowl. Despite numerous studies of avian bioenergetics in freshwater systems, less is known of the energetic capacity of estuarine systems. In San Francisco Bay, managed saline ponds converted from former commercial salt evaporation ponds form part of the largest wetland restoration project on the Pacific coast of North America. A daily-ration model was applied to assess carrying capacity for diving ducks and shorebirds during four winter seasons (2007–2010) in seasonal and circulation ponds, each in two salinity classes. Diving ducks comprised an estimated 35,450 ± 1,559 ( ± SE) in average years and 45,458 ± 1,653 in peak years with > 95% in circulation ponds. Shorebirds comprised 64,253 ± 14,838 ( ± SE) in average years and 108,171 ± 4,854 in peak years with > 64% in seasonal ponds. Macroinvertebrate energy density was highest in mesohaline (5–30 ppt) circulation ponds and lowest in seasonal ponds for both guilds. Energy requirements for diving ducks in mesohaline followed by low-hyperhaline (30–80 ppt) circulation ponds were mostly met by available prey energy. Available energy for shorebirds was substantially less than they required in seasonal ponds but exceeded their needs in mesohaline circulation ponds. Mesohaline circulation ponds supported 9,443 ± 1,649 ( ± SE) shorebird use-days·ha-1 of accessible habitat and 2,297 ± 402 diving duck use-days·ha-1 of accessible habitat, twice the capacity of low-hyperhaline circulation ponds and greater than five times that of seasonal ponds for both guilds. Our results indicated that reducing salinity to mesohaline levels and altering water depth to increase accessibility substantially increased energy available for these species in estuarine managed ponds.

  19. Danish diving-related fatalities 1999-2012

    DEFF Research Database (Denmark)

    Vinkel, Julie; Bak, Peter; Hyldegaard, Ole

    2016-01-01

    AIM: The purpose was to explore causative tendencies among diving fatalities to prevent similar injuries in the future. METHODS: We report 33 fatal diving injuries that occurred among Danish divers during the period 1999-2012 in Scandinavian waters. The study was performed as a retrospective...... overview. The empiric data consists of police reports, forensic autopsy reports and examination of the diving equipment. Data were assembled and analyzed using Pivot and Excel. Frequencies and means (± SD) were used to describe categorical and continuous variables respectively. RESULTS: The mean age was 38.......9 years and drowning was considered the cause of death in 24 of 28 divers for whom a diagnosis was possible. Elevated body mass index (18 of 22 divers had a BMI 〉 25) was overrepresented in our group compared to the background population. A drysuit was worn by 17 divers. Diving independently of a dive...

  20. Novel locomotor muscle design in extreme deep-diving whales.

    Science.gov (United States)

    Velten, B P; Dillaman, R M; Kinsey, S T; McLellan, W A; Pabst, D A

    2013-05-15

    Most marine mammals are hypothesized to routinely dive within their aerobic dive limit (ADL). Mammals that regularly perform deep, long-duration dives have locomotor muscles with elevated myoglobin concentrations that are composed of predominantly large, slow-twitch (Type I) fibers with low mitochondrial volume densities (V(mt)). These features contribute to extending ADL by increasing oxygen stores and decreasing metabolic rate. Recent tagging studies, however, have challenged the view that two groups of extreme deep-diving cetaceans dive within their ADLs. Beaked whales (including Ziphius cavirostris and Mesoplodon densirostris) routinely perform the deepest and longest average dives of any air-breathing vertebrate, and short-finned pilot whales (Globicephala macrorhynchus) perform high-speed sprints at depth. We investigated the locomotor muscle morphology and estimated total body oxygen stores of several species within these two groups of cetaceans to determine whether they (1) shared muscle design features with other deep divers and (2) performed dives within their calculated ADLs. Muscle of both cetaceans displayed high myoglobin concentrations and large fibers, as predicted, but novel fiber profiles for diving mammals. Beaked whales possessed a sprinter's fiber-type profile, composed of ~80% fast-twitch (Type II) fibers with low V(mt). Approximately one-third of the muscle fibers of short-finned pilot whales were slow-twitch, oxidative, glycolytic fibers, a rare fiber type for any mammal. The muscle morphology of beaked whales likely decreases the energetic cost of diving, while that of short-finned pilot whales supports high activity events. Calculated ADLs indicate that, at low metabolic rates, both beaked and short-finned pilot whales carry sufficient onboard oxygen to aerobically support their dives.

  1. Evaluation of decompression safety in an occupational diving group using self reported diving exposure and health status.

    Science.gov (United States)

    Doolette, D J; Gorman, D F

    2003-06-01

    Many occupational diving groups have substantially different diving patterns to those for which decompression schedules are validated. To evaluate tuna farm occupational diving practice against existing decompression models and describe a method for collecting and modelling self reported field decompression data. Machine readable objective depth/time profiles were obtained from depth/time recorders worn by tuna farm occupational divers. Divers' health status was measured at the end of each working day using a self administered health survey that produces an interval diver health score (DHS) with possible values ranging from 0 to 30. Depth/time profiles were analysed according to existing decompression models. The contribution of diving exposure and between diver variability to DHS was evaluated using linear regression. The mean risk of decompression sickness was calculated as 0.005 (SD 0.003, n = 383). The mean DHS following diving was 3 (SD 2, n = 383) and following non-diving activities was 1 (SD 1, n = 41). After accounting for between diver variability in intercept, DHS was found to increase one unit for every 1% increase in the risk of decompression sickness. A method has been established for the collection and analysis of self reported objective decompression data from occupational diving groups that can potentially be used as the basis for development of purpose designed occupational diving decompression schedules.

  2. Can dive cycle models predict patterns of foraging behaviour? Diving by common eiders in an Arctic polynya

    NARCIS (Netherlands)

    Heath, J.P.; Gilchrist, H.G.; Ydenberg, R.C.

    2007-01-01

    There has been wide empirical and theoretical interest in how diving animals allocate time between obtaining oxygen at the surface and foraging at depth. Assuming diminishing returns in oxygen gain at the surface, classic diving models predict that time on the surface should increase, while time

  3. Blood Oxygen Conservation in Diving Sea Lions: How Low Does Oxygen Really Go?

    Science.gov (United States)

    2014-09-30

    diving emperor penguins (Ponganis, unpublished data), and in deep-diving bottlenose dolphins ( Tursiops truncatus ), which also dive on inspiration...278-289. Williams, T.M., J.E. Haun and W.A. Friedl. 1999. The diving physiology of bottlenose dolphins ( Tursiops truncatus ). I. Balancing the

  4. Deep-Diving California Sea Lions: Are They Pushing Their Physiological Limit

    Science.gov (United States)

    2015-09-30

    in deep-diving emperor penguins (Wright et al. 2014), and in deep-diving bottlenose dolphins ( Tursiops truncatus ), which also dive on inspiration...Friedl. 1999. The diving physiology of bottlenose dolphins ( Tursiops truncatus ). I. Balancing the demands of exercise for energy conservation at depth

  5. Sports-related lung injury during breath-hold diving.

    Science.gov (United States)

    Mijacika, Tanja; Dujic, Zeljko

    2016-12-01

    The number of people practising recreational breath-hold diving is constantly growing, thereby increasing the need for knowledge of the acute and chronic effects such a sport could have on the health of participants. Breath-hold diving is potentially dangerous, mainly because of associated extreme environmental factors such as increased hydrostatic pressure, hypoxia, hypercapnia, hypothermia and strenuous exercise.In this article we focus on the effects of breath-hold diving on pulmonary function. Respiratory symptoms have been reported in almost 25% of breath-hold divers after repetitive diving sessions. Acutely, repetitive breath-hold diving may result in increased transpulmonary capillary pressure, leading to noncardiogenic oedema and/or alveolar haemorrhage. Furthermore, during a breath-hold dive, the chest and lungs are compressed by the increasing pressure of water. Rapid changes in lung air volume during descent or ascent can result in a lung injury known as pulmonary barotrauma. Factors that may influence individual susceptibility to breath-hold diving-induced lung injury range from underlying pulmonary or cardiac dysfunction to genetic predisposition.According to the available data, breath-holding does not result in chronic lung injury. However, studies of large populations of breath-hold divers are necessary to firmly exclude long-term lung damage. Copyright ©ERS 2016.

  6. Postmortem CT appearance of gas collections in fatal diving accidents.

    Science.gov (United States)

    Laurent, Pierre-Eloi; Coulange, Mathieu; Mancini, Julien; Bartoli, Christophe; Desfeux, Jacques; Piercecchi-Marti, Marie-Dominique; Gorincour, Guillaume

    2014-09-01

    OBJECTIVE. The purpose of our study was to define the postmortem CT semiology of gas collections linked to putrefaction, postmortem "off-gassing," and decompression illness after fatal diving accidents and to establish postmortem CT diagnostic criteria to distinguish the different causes of death in diving. SUBJECTS AND METHODS. A 4-year prospective study was conducted including cases of death during diving. A hyperbaric physician analyzed the circumstances of death and the dive profile, and an autopsy was performed. Subjects were divided into three groups according to the analysis from their dive profile: decompression illness, death after decompression dive without decompression illness, and death after nondecompression dive without decompression illness. Full-body postmortem CT was performed before autopsy. RESULTS. The presence of intraarterial gas associated with death by decompression illness had a negative predictive value (NPV) of 100%, but the positive predictive value (PPV) was only 54% because of postmortem off-gassing. The PPV reached 70% when considering pneumatization of the supraaortic trunks. Pneumothorax, subcutaneous emphysema, and intraarterial gas, all of which are classic criteria for decompression illness diagnosis, are not specific for decompression illness. CONCLUSION. This study is the first to show that pneumothorax, subcutaneous emphysema, and intraarterial gas, all of which are classic criteria for decompression illness diagnosis, are not specific for decompression illness. Complete pneumatization of supraaortic trunks is the best postmortem CT criteria to detect a fatal decompression illness when CT is performed within 24 hours after death.

  7. Early diving behaviour in juvenile penguins: improvement or selection processes.

    Science.gov (United States)

    Orgeret, Florian; Weimerskirch, Henri; Bost, Charles-André

    2016-08-01

    The early life stage of long-lived species is critical to the viability of population, but is poorly understood. Longitudinal studies are needed to test whether juveniles are less efficient foragers than adults as has been hypothesized. We measured changes in the diving behaviour of 17 one-year-old king penguins Aptenodytes patagonicus at Crozet Islands (subantartic archipelago) during their first months at sea, using miniaturized tags that transmitted diving activity in real time. We also equipped five non-breeder adults with the same tags for comparison. The data on foraging performance revealed two groups of juveniles. The first group made shallower and shorter dives that may be indicative of early mortality while the second group progressively increased their diving depths and durations, and survived the first months at sea. This surviving group of juveniles required the same recovery durations as adults, but typically performed shallower and shorter dives. There is thereby a relationship between improved diving behaviour and survival in young penguins. This long period of improving diving performance in the juvenile life stage is potentially a critical period for the survival of deep avian divers and may have implications for their ability to adapt to environmental change. © 2016 The Authors.

  8. Asthma and recreational SCUBA diving: a systematic review.

    Science.gov (United States)

    Koehle, Michael; Lloyd-Smith, Rob; McKenzie, Don; Taunton, Jack

    2003-01-01

    Asthma has traditionally been a contraindication to recreational self-contained underwater breathing apparatus (SCUBA) diving, although large numbers of patients with asthma partake in diving. The purpose of this paper is to review all the research relevant to the issue of the safety of asthma in divers. MEDLINE and MDConsult were searched for papers between 1980-2002. Keywords used for the search were 'asthma', 'SCUBA' and 'diving'. Additional references were reviewed from the bibliographies of received articles.A total of fifteen studies were identified as relevant to the area. These included three surveys of divers with asthma, four case series and eight mechanistic investigations of the effect of diving on pulmonary function. The survey data showed a high prevalence of asthma among recreational SCUBA divers, similar to the prevalence of asthma among the general population. There was some weak evidence for an increase in rates of decompression illness among divers with asthma. In healthy participants, wet hyperbaric chamber and open-water diving led to a decrease in forced vital capacity, forced expired volume over 1.0 second and mid-expiratory flow rates. In participants with asymptomatic respiratory atopy, diving caused a decrease in airway conductivity.There is some indication that asthmatics may be at increased risk of pulmonary barotrauma, but more research is necessary. Decisions regarding diving participation among asthmatics must be made on an individual basis involving the patient through informed, shared decision making.

  9. Diving response in rats: role of the subthalamic vasodilator area.

    Directory of Open Access Journals (Sweden)

    Eugene Golanov

    2016-09-01

    Full Text Available Diving response is a powerful integrative response targeted toward survival of the hypoxic/anoxic conditions. Being present in all animals and humans it allows to survive adverse conditions like diving. Earlier we discovered that forehead stimulation affords neuroprotective effect decreasing infarction volume triggered by permanent occlusion of the middle cerebral artery in rats. We hypothesized that cold stimulation of the forehead induces diving response in rats, which, in turn, exerts neuroprotection. We compared autonomic (AP, HR, CBF and EEG responses to the known diving response-triggering stimulus, ammonia stimulation of the nasal mucosa, cold stimulation of the forehead, and cold stimulation of the glabrous skin of the tail base in anesthetized rats. Responses in AP, HR, CBF and EEG to cold stimulation of the forehead and ammonia vapors instillation into the nasal cavity were comparable and differed significantly from responses to the cold stimulation of the tail base. Excitotoxic lesion of the subthalamic vasodilator area, which is known to participate in CBF regulation and to afford neuroprotection upon excitation, failed to affect autonomic components of the diving response evoked by forehead cold stimulation or nasal mucosa ammonia stimulation. We conclude that cold stimulation of the forehead triggers physiological response comparable to the response evoked by ammonia vapor instillation into the nasal cavity, which considered as stimulus triggering protective diving response. These observations may explain the neuroprotective effect of the forehead stimulation. Data demonstrate that subthalamic vasodilator area does not directly participate in the autonomic adjustments accompanying diving response, however, it is involved in diving-evoked modulation of EEG. We suggest that forehead stimulation can be employed as a stimulus capable of triggering oxygen-conserving diving response and can be used for neuroprotective therapy.

  10. Optimal diving behaviour and respiratory gas exchange in birds.

    Science.gov (United States)

    Halsey, Lewis G; Butler, Patrick J

    2006-11-01

    This review discusses the advancements in our understanding of the physiology and behaviour of avian diving that have been underpinned by optimal foraging theory and the testing of optimal models. To maximise their foraging efficiency during foraging periods, diving birds must balance numerous factors that are directly or indirectly related to the replenishment of the oxygen stores and the removal of excess carbon dioxide. These include (1) the time spent underwater (which diminishes the oxygen supply, increases carbon dioxide levels and may even include a build up of lactate due to anaerobic metabolism), (2) the time spent at the surface recovering from the previous dive and preparing for the next (including reloading their oxygen supply, decreasing their carbon dioxide levels and possibly also metabolising lactate) and (3) the trade-off between maximising oxygen reserves for consumption underwater by taking in more air to the respiratory system, and minimising the energy costs of positive buoyancy caused by this air, to maximise the time available underwater to forage. Due to its importance in avian diving, replenishment of the oxygen stores has become integral to models of optimal diving, which predict the time budgeting of animals foraging underwater. While many of these models have been examined qualitatively, such tests of predictive trends appear fallible and only quantifiable support affords strong evidence of their predictive value. This review describes how the quantification of certain optimal diving models, using tufted ducks, indeed demonstrates some predictive success. This suggests that replenishment of the oxygen stores and removal of excess carbon dioxide have significant influences on the duration of the surface period between dives. Nevertheless, present models are too simplistic to be robust predictors of diving behaviour for individual animals and it is proposed that they require refinement through the incorporation of other variables that also

  11. [Diagnosis and treatment of diving accidents. New German guidelines for diving accidents 2014-2017].

    Science.gov (United States)

    Jüttner, B; Wölfel, C; Liedtke, H; Meyne, K; Werr, H; Bräuer, T; Kemmerer, M; Schmeißer, G; Piepho, T; Müller, O; Schöppenthau, H

    2015-06-01

    In 2015 the German Society for Diving and Hyperbaric Medicine (GTÜM) and the Swiss Underwater and Hyperbaric Medical Society (SUHMS) published the updated guidelines on diving accidents 2014-2017. These multidisciplinary guidelines were developed within a structured consensus process by members of the German Interdisciplinary Association for Intensive Care and Emergency Medicine (DIVI), the Sports Divers Association (VDST), the Naval Medical Institute (SchiffMedInst), the Social Accident Insurance Institution for the Building Trade (BG BAU), the Association of Hyperbaric Treatment Centers (VDD) and the Society of Occupational and Environmental Medicine (DGAUM). This consensus-based guidelines project (development grade S2k) with a representative group of developers was conducted by the Association of Scientific Medical Societies in Germany. It provides information and instructions according to up to date evidence to all divers and other lay persons for first aid recommendations to physician first responders and emergency physicians as well as paramedics and all physicians at therapeutic hyperbaric chambers for the diagnostics and treatment of diving accidents. To assist in implementing the guideline recommendations, this article summarizes the rationale, purpose and the following key action statements: on-site 100% oxygen first aid treatment, still patient positioning and fluid administration are recommended. Hyperbaric oxygen (HBO) recompression remains unchanged the established treatment in severe cases with no therapeutic alternatives. The basic treatment scheme recommended for diving accidents is hyperbaric oxygenation at 280 kPa. For quality management purposes there is a need in the future for a nationwide register of hyperbaric therapy.

  12. Alveolar Hemorrhage After Scuba Diving: A Case Report

    Directory of Open Access Journals (Sweden)

    Ming-Ju Tsai

    2010-07-01

    Full Text Available Self-contained underwater breathing apparatus (scuba diving is increasingly popular in Taiwan. There are few references in the literature regarding pulmonary hemorrhage as the sole manifestation of pulmonary barotrauma in scuba divers, and no study from Taiwan was found in the literature. We present the case of a 25-year-old man who suffered alveolar hemorrhage related to pulmonary barotrauma as a complication of scuba diving. To our knowledge, this is the first case report describing a Taiwanese subject suffering from non-fatal pulmonary hemorrhage after scuba diving.

  13. Effects of successive air and trimix dives on human cardiovascular function.

    Science.gov (United States)

    Marinovic, Jasna; Ljubkovic, Marko; Obad, Ante; Bakovic, Darija; Breskovic, Toni; Dujic, Zeljko

    2009-12-01

    The use of trimix (a mixture of oxygen, helium, and nitrogen) has significantly increased among the diver population. However, data indicating how trimix dives at most common depths affect the cardiovascular function are sparse. The purpose of this study was to investigate the cardiovascular effects of trimix dives and compare them with air dives and to determine whether the repetition of dives in successive days affects their extent. Nine professional divers performed four dives in consecutive days where the dive depth was progressively increased to the maximum of 55 m. Divers used air in the first dive, nitrox 25 in the second, and trimix 20/30 in the third and fourth dives. Echocardiography was performed before and after each dive. After each dive, a significantly decreased left ventricular ejection fraction and fractional shortening and an increased end-systolic volume without a change in end-diastolic volume were found, indicating a depressed systolic function of the left side of the heart. Assessment of the ratio between pulmonary artery acceleration time and right ventricular ejection time (used as an indicator of pulmonary artery pressure (PAP)) revealed an increase in PAP after all the dives. No physiologically relevant cumulative effects of the multiple dives or signs of acclimatization were found. The current study shows that the cardiovascular effects of trimix dives do not differ from those of the dives with compressed air. However, it suggests that even a very safe and conservative trimix diving profile exerts significant cardiovascular effects.

  14. Governar o estado para a participação de entidades privadas na provisão, financiamento e gestão dos sistemas educativos na União Europeia Governing the State for the involvement of private commercial and non-commercial entities in the provision, financing and management of education systems in the European Union

    Directory of Open Access Journals (Sweden)

    Clementina Marques Cardoso

    2009-10-01

    Full Text Available A participação de entidades privadas comerciais¹ e não-comerciais na gestão, financiamento, provisão, avaliação e inspecção da educação na União Europeia é consolidada através de parcerias, contratação directa, criação de serviços paralelos. Essa consolidação é mediada pelas condições histórico-político-económicas de cada país e o seu quadro de acção distingue-se das regras de decisão pública. As funções do Estado e o papel do governo alteram-se para acompanhar e estimular essa participação e os efeitos desta alteração são vísiveis ao nível das regras da gestão, administração, financiamento e actividade reguladora que se reconfiguram como consequência da redefinição dos mecanismos de financiamento e do que se entende por autonomia escolar.The involvement of private commercial and noncommercial entities in the management, financing, provision, assessment and inspection of education in the European Union is consolidating through partnerships and commercial contracts and the creation of parallel services. This consolidation is mediated by each country's historical-political-economic conditions and its framework of action is different from public decision-making rules. The functions of the state and the role of governments are changing to follow and to stimulate such involvement. The effects of such changes can be seen in the rules of management, administration, financing and regulatory activities, which that are reconfigured by the redefinition of financing mechanisms and by what is understood to be school autonomy.

  15. The development of hyperbaric and diving medicine in Singapore.

    Science.gov (United States)

    Chng, J; Low, C T; Kang, W L

    2011-12-01

    Hyperbaric oxygen therapy is a noninvasive therapy used in the treatment of diving-related medical illnesses. It is an important adjunct in the management of a variety of medical conditions. The Republic of Singapore Navy Medical Service (NMS) is the main driver of the development of hyperbaric and diving medicine in Singapore. The practice of hyperbaric medicine has inherent risks, and unregulated application of this therapy may do more harm than good. NMS and Singapore General Hospital (SGH) signed a Memorandum of Understanding to combine NMS' experience with the clinical expertise of SGH to provide holistic care for diving and clinical hyperbaric treatment patients. This collaboration would increase the profile of this clinical specialty in Singapore, and help to establish safe clinical practice guidelines, training and accreditation requirements for diving and hyperbaric medicine practitioners in Singapore, thus ensuring that the practice of bona fide hyperbaric medicine is safeguarded and patient care is not compromised.

  16. Underwater and Dive Station Work-Site Noise Surveys

    National Research Council Canada - National Science Library

    Wolgemuth, Keith S; Cudahy, Edward A; Schwaller, Derek W

    2008-01-01

    Previous work performed by the Naval Submarine Medical Research Laboratory (NSMRL) had developed in-water permissible continuous noise exposure guidance Work performed by the Navy Experimental Diving Unit...

  17. Dives from missions of the NOAA ship Okeanos Explorer.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Dataset shows dives made by a Remotely Operated Vehicle (ROV) or an Autonomous Underwater Vehicle (AUV) from the NOAA ship Okeanos Explorer during expeditions from...

  18. Dive Tracks from missions of the NOAA ship Okeanos Explorer.

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Dataset shows dive tracks made by a Remotely Operated Vehicle (ROV) or an Autonomous Underwater Vehicle (AUV) from the NOAA ship Okeanos Explorer during expeditions...

  19. Preventable Diving-related Ocular Barotrauma: A Case Report

    Directory of Open Access Journals (Sweden)

    Serkan Ergözen

    2017-12-01

    Full Text Available The mystical beauty of the subaquatic world is undoubtedly attractive, and many techniques and forms of equipment have been developed in the last few decades to allow us to explore the underwater world. A swimmer or diver needs swimming goggles or a diving mask to have clear vision because of the refraction problem between the eye and the water interface. Although these items are effective for clear vision, they can result in “ocular or facial barotrauma of descent” during diving. It is possible to prevent these types of barotrauma with correct techniques and precautions, thus enabling the continuation of recreational diving without recurrence. In this paper, we report a case of subconjunctival hemorrhage caused by breath-hold diving and discuss the causes of ocular barotrauma of descent and preventive measures.

  20. Provisional Crown Dislodgement during Scuba Diving: A Case of Barotrauma

    OpenAIRE

    Meenal Nitin Gulve; Nitin Dilip Gulve

    2013-01-01

    Changes in ambient pressure, for example, during flying, diving, or hyperbaric oxygen therapy, can lead to barotrauma. Although it may seem that this issue was neglected in dental education and research in recent decades, familiarity with and understanding of these facts may be of importance for dental practitioners. We report the case of a patient who experienced barotrauma involving dislodgement of a provisional crown during scuba diving. Patients who are exposed to pressure changes as a pa...

  1. The Mammalian Diving Response: An Enigmatic Reflex to Preserve Life?

    Science.gov (United States)

    2013-01-01

    The mammalian diving response is a remarkable behavior that overrides basic homeostatic reflexes. It is most studied in large aquatic mammals but is seen in all vertebrates. Pelagic mammals have developed several physiological adaptations to conserve intrinsic oxygen stores, but the apnea, bradycardia, and vasoconstriction is shared with those terrestrial and is neurally mediated. The adaptations of aquatic mammals are reviewed here as well as the neural control of cardiorespiratory physiology during diving in rodents. PMID:23997188

  2. B-type natriuretic peptide secretion following scuba diving

    DEFF Research Database (Denmark)

    Passino, Claudio; Franzino, Enrico; Giannoni, Alberto

    2011-01-01

    To examine the neurohormonal effects of a scuba dive, focusing on the acute changes in the plasma concentrations of the different peptide fragments from the B-type natriuretic peptide (BNP) precursor.......To examine the neurohormonal effects of a scuba dive, focusing on the acute changes in the plasma concentrations of the different peptide fragments from the B-type natriuretic peptide (BNP) precursor....

  3. THE INFLUENCE OF AUTONOMOUS DIVING ON SENSES AND MENTAL PROCESSES

    Directory of Open Access Journals (Sweden)

    Dragan Krivokapić

    2010-09-01

    Full Text Available Diving is classified within a group of sports accompanied with an increased risk, yet it is a sport of full biological significance. Diving implies change of immediate human environment. Water, as the natural ambient for diving issues specific demands to the organism, which in turn influence decrease in psychophysical abilities when underwater, and in some instances, immediately after emerging from it. The most important factors influencing decrease in psychophysical abilities are: immersion, increased ambient pressure, characteristics of diving equipment and atmosphere separation. The senses and the mental processes of the diver are significantly altered during the autonomous diving. Loss of self-weight perception and pressure put on joints cause disorders in function of kinesthetic senses and vestibular apparatus, which in turn becomes reflected on proprioception. Coldness of water, especially at grater depths, induces decline in pain sensation as well as in aptness and mobility of fingers. Sight remains normal, but the image received is slightly changed due to refraction of light on boundary surfaces. Visual field is narrowed down to fit the limited diving mask field of view. At the same time, diffusion of light and color absorption brings about the loss of both ability to perceive things and contrasts when at depths .Objects tend to appear bigger and closer underwater. Hearing is changed owing to the fact that the sound is not carried through the air but through the water, yet the speed of transmission causes only slight difference of left and right ear stimulation. Mental processes, informationassessment, creation of clear mental images of the actual moment, abstract thinking, decision making, etc. are not effective and precise. This state can be partly ascribed to the above mentioned problems with senses, partly to the greater influence of emotional as opposed to rational, but also to the narcotic effect of nitrogen that is produced while

  4. Selective brain cooling and its vascular basis in diving seals.

    Science.gov (United States)

    Blix, Arnoldus Schytte; Walløe, Lars; Messelt, Edward B; Folkow, Lars P

    2010-08-01

    Brain (T(brain)), intra-aorta (T(aorta)), latissimus dorsi muscle (T(m)) and rectal temperature (T(r)) were measured in harp (Pagophilus groenlandicus) and hooded (Cystophora cristata) seals during experimental dives in 4 degrees C water. The median brain cooling was about 1 degrees C during 15 min diving, but in some cases it was as much as 2.5 degrees C. Cooling rates were slow for the first couple of minutes, but increased significantly after about 5 min of diving. The onset of cooling sometimes occurred before the start of the dive, confirming that the cooling is under cortical control, like the rest of the diving responses. T(aorta) also fell significantly, and was always lower than T(brain), while T(m) was fairly stable during dives. Detailed studies of the vascular anatomy of front flippers revealed that brachial arterial blood can be routed either through flipper skin capillaries for nutritive purposes and return through sophisticated vascular heat exchangers to avoid heat loss to the environment, or, alternatively, through numerous arterio-venous shunts in the skin and return by way of large superficial veins, which then carry cold blood to the heart. In the latter situation the extent to which the brain is cooled is determined by the ratio of carotid to brachial arterial blood flow, and water temperature, and the cooling is selective in that only those organs that are circulated will be cooled. It is concluded that T(brain) is actively down-regulated during diving, sometimes by as much as 2.5 degrees C, whereby cerebral oxygen requirements may be reduced by as much as 25% during extended dives.

  5. Techniques for Diving Deeper Than 1,500 Feet,

    Science.gov (United States)

    1980-03-01

    was injection of nitrogen 7 times during compres- sion every 100 m from 300 m rather than just at the start or end. Comex mnade a similar trimix dive...possibility and may, indeed, become hazardous at marginally deeper depths. The use of TRIMIX in diving to depths ranging from 150 m to 650 m appears to be...and significant evidence was presented that the addition of nitrogen to oxy-helium breathing mixtures ( TRIMIX ) is beneficial and opens up the

  6. Postural control in a simulated saturation dive to 240 msw.

    OpenAIRE

    Goplen, Frederik Kragerud; Aasen, T. B.; Nordahl, Stein Helge G

    2007-01-01

    INTRODUCTION: There is evidence that increased ambient pressure causes an increase in postural sway. This article documents postural sway at pressures not previously studied and discusses possible mechanisms. METHODS: Eight subjects participated in a dry chamber dive to 240 msw (2.5 MPa) saturation pressure. Two subjects were excluded due to unilateral caloric weakness before the dive. Postural sway was measured on a force platform. The path length described by the center of pr...

  7. Activation of Brainstem Neurons by Underwater Diving in the Rat

    Science.gov (United States)

    Panneton, W. Michael; Gan, Qi; Le, Jason; Livergood, Robert S.; Clerc, Philip; Juric, Rajko

    2012-01-01

    The mammalian diving response is a powerful autonomic adjustment to underwater submersion greatly affecting heart rate, arterial blood pressure, and ventilation. The bradycardia is mediated by the parasympathetic nervous system, arterial blood pressure is mediated via the sympathetic system and still other circuits mediate the respiratory changes. In the present study we investigate the cardiorespiratory responses and the brainstem neurons activated by voluntary diving of trained rats, and, compare them to control and swimming animals which did not dive. We show that the bradycardia and increase in arterial blood pressure induced by diving were significantly different than that induced by swimming. Neuronal activation was calculated after immunohistochemical processing of brainstem sections for Fos protein. Labeled neurons were counted in the caudal pressor area, the medullary dorsal horn, subnuclei of the nucleus tractus solitarii (NTS), the nucleus raphe pallidus (RPa), the rostroventrolateral medulla, the A5 area, the nucleus locus coeruleus, the Kölliker–Fuse area, and the external lateral and superior lateral subnuclei of the parabrachial nucleus. All these areas showed significant increases in Fos labeling when data from voluntary diving rats were compared to control rats and all but the commissural subnucleus of the NTS, A5 area, and RPa were significantly different from swimming rats. These data provide a substrate for more precise experiments to determine the role of these nuclei in the reflex circuits driving the diving response. PMID:22563319

  8. Poor flight performance in deep-diving cormorants.

    Science.gov (United States)

    Watanabe, Yuuki Y; Takahashi, Akinori; Sato, Katsufumi; Viviant, Morgane; Bost, Charles-André

    2011-02-01

    Aerial flight and breath-hold diving present conflicting morphological and physiological demands, and hence diving seabirds capable of flight are expected to face evolutionary trade-offs regarding locomotory performances. We tested whether Kerguelen shags Phalacrocorax verrucosus, which are remarkable divers, have poor flight capability using newly developed tags that recorded their flight air speed (the first direct measurement for wild birds) with propeller sensors, flight duration, GPS position and depth during foraging trips. Flight air speed (mean 12.7 m s(-1)) was close to the speed that minimizes power requirement, rather than energy expenditure per distance, when existing aerodynamic models were applied. Flights were short (mean 92 s), with a mean summed duration of only 24 min day(-1). Shags sometimes stayed at the sea surface without diving between flights, even on the way back to the colony, and surface durations increased with the preceding flight durations; these observations suggest that shags rested after flights. Our results indicate that their flight performance is physiologically limited, presumably compromised by their great diving capability (max. depth 94 m, duration 306 s) through their morphological adaptations for diving, including large body mass (enabling a large oxygen store), small flight muscles (to allow for large leg muscles for underwater propulsion) and short wings (to decrease air volume in the feathers and hence buoyancy). The compromise between flight and diving, as well as the local bathymetry, shape the three-dimensional foraging range (<26 km horizontally, <94 m vertically) in this bottom-feeding cormorant.

  9. Oxygen saturation in free-diving whales: optical sensor development

    Science.gov (United States)

    Gutierrez-Herrera, Enoch; Vacas-Jacques, Paulino; Anderson, Rox; Zapol, Warren; Franco, Walfre

    2013-02-01

    Mass stranding of live whales has been explained by proposing many natural or human-related causes. Recent necropsy reports suggest a link between the mass stranding of beaked whales and the use of naval mid-frequency sonar. Surprisingly, whales have experienced symptoms similar to those caused by inert gas bubbles in human divers. Our goal is to develop a compact optical sensor to monitor the consumption of the oxygen stores in the muscle of freely diving whales. To this end we have proposed the use of a near-infrared phase-modulated frequency-domain spectrophotometer, in reflectance mode, to probe tissue oxygenation. Our probe consists of three main components: radiofrequency (RF) modulated light sources, a high-bandwidth avalanche photodiode with transimpedance amplifier, and a RF gain and phase detector. In this work, we concentrate on the design and performance of the light sensor, and its corresponding amplifier unit. We compare three state-of-the-art avalanche photodiodes: one through-hole device and two surface-mount detectors. We demonstrate that the gain due to the avalanche effect differs between sensors. The avalanche gain near maximum bias of the through-hole device exceeds by a factor of 2.5 and 8.3 that of the surface-mount detectors. We present the behavior of our assembled through-hole detector plus high-bandwidth transimpedance amplifier, and compare its performance to that of a commercially available module. The assembled unit enables variable gain, its phase noise is qualitatively lower, and the form factor is significantly smaller. Having a detecting unit that is compact, flexible, and functional is a milestone in the development of our tissue oxygenation tag.

  10. Research on the performance of low-lift diving tubular pumping system by CFD and Test

    Science.gov (United States)

    Xia, Chenzhi; Cheng, Li; Liu, Chao; Zhou, Jiren; Tang, Fangping; Jin, Yan

    2016-11-01

    Post-diving tubular pump is always used in large-discharge & low-head irrigation or storm drainage pumping station, its impeller and motor share the same shaft. Considering diving tubular pump system's excellent hydraulic performance, compact structure, good noise resistance and low operating cost, it is used in Chinese pump stations. To study the hydraulic performance and pressure fluctuation of inlet and outlet passage in diving tubular pump system, both of steady and unsteady full flow fields are numerically simulated at three flow rate conditions by using CFD commercial software. The asymmetry of the longitudinal structure of inlet passage affects the flow pattern on outlet. Especially at small flow rate condition, structural asymmetry will result in the uneven velocity distribution on the outlet of passage inlet. The axial velocity distribution uniformity increases as the flow rate increases on the inlet of passage inlet, and there is a positive correlation between hydraulic loss in the passage inlet and flow rate's quadratic. The axial velocity distribution uniformity on the outlet of passage inlet is 90% at design flow rate condition. The predicted result shows the same trend with test result, and the range of high efficiency area between predicted result and test result is almost identical. The dominant frequency of pressure pulsation is low frequency in inlet passage at design condition. The dominant frequency is high frequency in inlet passage at small and large flow rate condition. At large flow rate condition, the flow pattern is significantly affected by the rotation of impeller in inlet passage. At off-design condition, the pressure pulsation is strong at outlet passage. At design condition, the dominant frequency is 35.57Hz, which is double rotation frequency.

  11. The impact of consecutive freshwater trimix dives at altitude on human cardiovascular function.

    Science.gov (United States)

    Lozo, Mislav; Madden, Dennis; Gunjaca, Grgo; Ljubkovic, Marko; Marinovic, Jasna; Dujic, Zeljko

    2015-03-01

    Self-contained underwater breathing apparatus (SCUBA) diving is regularly associated with numerous asymptomatic changes in cardiovascular function. Freshwater SCUBA diving presents unique challenges compared with open sea diving related to differences in water density and the potential for dive locations at altitude. The aim of this study was to evaluate the impact of freshwater trimix diving at altitude on human cardiovascular function. Ten divers performed two dives in consecutive days at 294 m altitude with the surface interval of 24 h. Both dives were at a depth of 45 m with total dive time 29 and 26 min for the first and second dive, respectively. Assessment of venous gas embolization, hydration status, cardiac function and arterial stiffness was performed. Production of venous gas emboli was low, and there were no significant differences between the dives. After the first dive, diastolic blood pressure was significantly reduced, which persisted up to 24 h. Left ventricular stroke volume decreased, and heart rate increased after both dives. Pulse wave velocity was unchanged following the dives. However, the central and peripheral augmentation index became more negative after both dives, indicating reduced wave reflection. Ejection duration and round trip travel time were prolonged 24 h after the first dive, suggesting longer-lasting suppression of cardiac and endothelial function. This study shows that freshwater trimix dives with conservative profiles and low venous gas bubble loads can result in multiple asymptomatic acute cardiovascular changes some of which were present up to 24 h after dive. © 2014 Scandinavian Society of Clinical Physiology and Nuclear Medicine. Published by John Wiley & Sons Ltd.

  12. Variation in depth of whitetip reef sharks: does provisioning ecotourism change their behaviour?

    Science.gov (United States)

    Fitzpatrick, Richard; Abrantes, Kátya G.; Seymour, Jamie; Barnett, Adam

    2011-09-01

    In the dive tourism industry, shark provisioning has become increasingly popular in many places around the world. It is therefore important to determine the impacts that provisioning may have on shark behaviour. In this study, eight adult whitetip reef sharks Triaenodon obesus were tagged with time-depth recorders at Osprey Reef in the Coral Sea, Australia. Tags collected time and depth data every 30 s. The absolute change in depth over 5-min blocks was considered as a proxy for vertical activity level. Daily variations in vertical activity levels were analysed to determine the effects of time of day on whitetip reef shark behaviour. This was done for days when dive boats were absent from the area, and for days when dive boats were present, conducting shark provisioning. Vertical activity levels varied between day and night, and with the presence of boats. In natural conditions (no boats present), sharks remained at more constant depths during the day, while at night animals continuously moved up and down the water column, showing that whitetip reef sharks are nocturnally active. When boats were present, however, there were also long periods of vertical activity during the day. If resting periods during the day are important for energy budgets, then shark provisioning may affect their health. So, if this behaviour alteration occurs frequently, e.g., daily, this has the potential to have significant negative effects on the animals' metabolic rates, net energy gain and overall health, reproduction and fitness.

  13. Long-term changes in species composition and relative abundances of sharks at a provisioning site.

    Directory of Open Access Journals (Sweden)

    Juerg M Brunnschweiler

    Full Text Available Diving with sharks, often in combination with food baiting/provisioning, has become an important product of today's recreational dive industry. Whereas the effects baiting/provisioning has on the behaviour and abundance of individual shark species are starting to become known, there is an almost complete lack of equivalent data from multi-species shark diving sites. In this study, changes in species composition and relative abundances were determined at the Shark Reef Marine Reserve, a multi-species shark feeding site in Fiji. Using direct observation sampling methods, eight species of sharks (bull shark Carcharhinus leucas, grey reef shark Carcharhinus amblyrhynchos, whitetip reef shark Triaenodon obesus, blacktip reef shark Carcharhinus melanopterus, tawny nurse shark Nebrius ferrugineus, silvertip shark Carcharhinus albimarginatus, sicklefin lemon shark Negaprion acutidens, and tiger shark Galeocerdo cuvier displayed inter-annual site fidelity between 2003 and 2012. Encounter rates and/or relative abundances of some species changed over time, overall resulting in more individuals (mostly C. leucas of fewer species being encountered on average on shark feeding dives at the end of the study period. Differences in shark community composition between the years 2004-2006 and 2007-2012 were evident, mostly because N. ferrugineus, C. albimarginatus and N. acutidens were much more abundant in 2004-2006 and very rare in the period of 2007-2012. Two explanations are offered for the observed changes in relative abundances over time, namely inter-specific interactions and operator-specific feeding protocols. Both, possibly in combination, are suggested to be important determinants of species composition and encounter rates, and relative abundances at this shark provisioning site in Fiji. This study, which includes the most species from a spatially confined shark provisioning site to date, suggests that long-term provisioning may result in competitive

  14. Long-term changes in species composition and relative abundances of sharks at a provisioning site.

    Science.gov (United States)

    Brunnschweiler, Juerg M; Abrantes, Kátya G; Barnett, Adam

    2014-01-01

    Diving with sharks, often in combination with food baiting/provisioning, has become an important product of today's recreational dive industry. Whereas the effects baiting/provisioning has on the behaviour and abundance of individual shark species are starting to become known, there is an almost complete lack of equivalent data from multi-species shark diving sites. In this study, changes in species composition and relative abundances were determined at the Shark Reef Marine Reserve, a multi-species shark feeding site in Fiji. Using direct observation sampling methods, eight species of sharks (bull shark Carcharhinus leucas, grey reef shark Carcharhinus amblyrhynchos, whitetip reef shark Triaenodon obesus, blacktip reef shark Carcharhinus melanopterus, tawny nurse shark Nebrius ferrugineus, silvertip shark Carcharhinus albimarginatus, sicklefin lemon shark Negaprion acutidens, and tiger shark Galeocerdo cuvier) displayed inter-annual site fidelity between 2003 and 2012. Encounter rates and/or relative abundances of some species changed over time, overall resulting in more individuals (mostly C. leucas) of fewer species being encountered on average on shark feeding dives at the end of the study period. Differences in shark community composition between the years 2004-2006 and 2007-2012 were evident, mostly because N. ferrugineus, C. albimarginatus and N. acutidens were much more abundant in 2004-2006 and very rare in the period of 2007-2012. Two explanations are offered for the observed changes in relative abundances over time, namely inter-specific interactions and operator-specific feeding protocols. Both, possibly in combination, are suggested to be important determinants of species composition and encounter rates, and relative abundances at this shark provisioning site in Fiji. This study, which includes the most species from a spatially confined shark provisioning site to date, suggests that long-term provisioning may result in competitive exclusion among shark

  15. Some new cave diving exploration results from Croatian karst area

    Science.gov (United States)

    Garasic, Davor; Garasic, Mladen

    2017-04-01

    In the recent years, several international cave diving expeditions took place in the Dinaric karst of Croatia. The objectives were conducting a new research of previously known karstic springs and also exploring new ones. The deepest karst cave in Croatia filled with water is Crveno jezero (lake) near Imotski town, with water depth of 281 meters and total cave depth of 528 meters. Volume of water in this cave is about 16 millions m3. Diving expeditions were held in 1997 and 1998.The deepest karst spring in the Dinaric karst of Croatia is Vrelo of Una River (with max discharge about 100 m3/s), where divers measured depth of -248 meters. Explorations were made in 2007 and 2016. Sinac spring in Pla\\vsko Polje has been dived to the depth of -203 meters. Cave diving was done in 1984, 1999, 2003, 2007 - 2016. Furthermore, very popular springs of the river Kupa (-155 m) in Gorski Kotar (explored since1995 till 2015), river Gacka (-105 in depth, 1150m in length) in Lika, explored from 1992 to 2016, river Cetina (-110 m in depth, 1300 m in length), cave diving explored from 2000 to 2016 in the Dalmatinska Zagora, Rumin Veliki spring (- 150 m in depth) in the Sinjska Krajina (explored and dived in 2006 and 2010), than rivers Krnjeza and Krupa in Ravni kotari with diving depths of over 100 meters (in 2004 and 2005) and so on. Along the Adriatic coast in Croatia there are many deep and long submarine springs (vrulje), ie. caves under seawater springs. called - vruljas for example Vrulja Zecica with over 900 meters ine length and Vrulja Modrič with completely flooded cave channels that extend over 2300 meters in length. Cave diving was conducted from 2010 to 2016. Vrulja Dubci is also worth mentioning (dived and explored in 2000), 161 meters deep and so on. Tectonic activity plays a dominant role in the creation and function of these caves. Geological, hydrogeological and lithostratigraphic conditions are also very important in speleogenesis of these caves in Croatian karst

  16. Bilateral sectioning of the anterior ethmoidal nerves does not eliminate the diving response in voluntarily diving rats

    Science.gov (United States)

    Chotiyanonta, Jill S; DiNovo, Karyn M; McCulloch, Paul F

    2013-01-01

    The diving response is characterized by bradycardia, apnea, and increased peripheral resistance. This reflex response is initiated by immersing the nose in water. Because the anterior ethmoidal nerve (AEN) innervates the nose, our hypothesis was that intact AENs are essential for initiating the diving response in voluntarily diving rats. Heart rate (HR) and arterial blood pressure (BPa) were monitored using implanted biotransmitters. Sprague-Dawley rats were trained to voluntarily swim 5 m underwater. During diving, HR decreased from 480 ± 15 to 99 ± 5 bpm and BPa increased from 136 ± 2 to 187 ± 3 mmHg. Experimental rats (N = 9) then received bilateral AEN sectioning, while Sham rats (N = 8) did not. During diving in Experimental rats 7 days after AEN surgery, HR decreased from 478 ± 13 to 76 ± 4 bpm and BPa increased from 134 ± 3 to 186 ± 4 mmHg. Responses were similar in Sham rats. Then, during nasal stimulation with ammonia vapors in urethane-anesthetized Experimental rats, HR decreased from 368 ± 7 to 83 ± 4 bpm, and BPa increased from 126 ± 7 to 175 ± 4 mmHg. Responses were similar in Sham rats. Thus, 1 week after being sectioned the AENs are not essential for initiating a full cardiorespiratory response during both voluntary diving and nasal stimulation. We conclude that other nerve(s) innervating the nose are able to provide an afferent signal sufficient to initiate the diving response, although neuronal plasticity within the medullary dorsal horn may be necessary for this to occur. PMID:24400143

  17. The Use of Artificial Reefs for Recreational Diving

    Directory of Open Access Journals (Sweden)

    Tuğçe ŞENSURAT GENÇ

    2017-11-01

    Full Text Available Scuba diving has become a burgeoning branch of the tourism service. Various activities of recreational diving do not especially necessitate natural reefs-any varied vehicle such as ship, plane and other large structures may be adequately attractive. Coastal groups are turning to these structures by the way of supplying new locations for scuba diving tourists. Despite the lack of a global database, our literature review indicated extensive use of artificial reefs for recreation in the United States, currently viewed as the pioneering puissance and professional in the field. Moreover, the Canadian and Australian governments have both promoted several “ships to reef” programs focused on recreation. However, the used of three-dimensional structures (ships, planes etc. as artificial reefs in sensitive ecosystems such as the Mediterranean and Red Sea is not a common practice. Although scuba divers are interested in such type of structures, ships to reef is a matter of debate especially in the Mediterranean region. In Turkey, a National Artificial Reef Program was drafted in 2008, however there is no regulation at present about intentionally sinking a ship for the creation of recreational diving destinations. The aim of this review was to investigate the use of man-made structures as artificial reefs for recreational diving around the world.

  18. Recreational Diving Practice for Stress Management: An Exploratory Trial

    Directory of Open Access Journals (Sweden)

    Frédéric Beneton

    2017-12-01

    Full Text Available Background: Within the components of Scuba diving there are similarities with meditation and mindfulness techniques by training divers to be in a state of open monitoring associated with slow and ample breathing. Perceived stress is known to be diminished during meditation practice. This study evaluates the benefits of scuba diving on perceived stress and mindful functioning.Method: A recreational diving group (RDG; n = 37 was compared with a multisport control group (MCG; n = 30 on perceived stress, mood, well-being and mindfulness by answering auto-questionnaires before and after a 1-week long UCPA course. For the diving group, stability of the effects was evaluated 1 month later using similar auto-questionnaires.Results: Perceived stress did not decrease after the course for the MCG [ The divers showed a significant reduction on the perceived stress score (p < 0.05 with a sustainable effect (p = 0.01]. An improvement in mood scale was observed in both groups. This was associated to an increase in mindfulness abilities.Conclusions: The practice of a recreational sport improves the mood of subjects reporting the thymic benefits of a physical activity performed during a vacation period. The health benefits of recreational diving appear to be greater than the practice of other sports in reducing stress and improving well-being.

  19. Comparative histology of muscle in free ranging cetaceans: shallow versus deep diving species

    OpenAIRE

    Sierra, E.; Fernández, A; Espinosa de los Monteros, A.; Díaz-Delgado, J.; Y. Bernaldo de Quirós; N. García-Álvarez; Arbelo, M.; Herráez, P

    2015-01-01

    Different marine mammal species exhibit a wide range of diving behaviour based on their breath-hold diving capabilities. They are classically categorized as long duration, deep-diving and short duration, shallow-diving species. These abilities are likely to be related to the muscle characteristics of each species. Despite the increasing number of publications on muscle profile in different cetacean species, very little information is currently available concerning the characteristics of other...

  20. Dive Tourism and Local Communities: Active Participation or Subject to Impacts?Case Studies from Malaysia

    OpenAIRE

    Daldeniz, Bilge; Hampton, Mark P.

    2013-01-01

    Dive tourism impacts were examined in three Malaysian islands: Perhentian(backpackers), Redang (package tourism) and Mabul (upmarket dive tourism). Qualitative local participation approaches were applied to investigate whether host communities were merely reactive to dive tourism’s impacts. Dive tourism affected many aspects of community life. Besides physical/environmental impacts (new infrastructure), research found varied economic impacts including employment/business opportunities and dif...

  1. [Breath-hold diving--an increasing adventure sport with medical risks].

    Science.gov (United States)

    Lindholm, Peter; Gennser, Mikael

    2004-02-26

    Breath-hold diving as a recreational and competitive sports activity is on the increase. In this review physiological limitations and medical risks associated with breath-hold diving are discussed. Specific topics include hypoxia, ascent blackout, hyperventilation, squeeze or barotrauma of descent including effects on the pulmonary system, glossopharyngeal breathing, and decompression illness. It is also concluded that the health requirements for competitive breath-hold diving should follow essentially the same standards as used for SCUBA-diving.

  2. Dive and Explore: An Interactive Web Visualization that Simulates Making an ROV Dive to an Active Submarine Volcano

    Science.gov (United States)

    Weiland, C.; Chadwick, W. W.

    2004-12-01

    Several years ago we created an exciting and engaging multimedia exhibit for the Hatfield Marine Science Center that lets visitors simulate making a dive to the seafloor with the remotely operated vehicle (ROV) named ROPOS. The exhibit immerses the user in an interactive experience that is naturally fun but also educational. The public display is located at the Hatfield Marine Science Visitor Center in Newport, Oregon. We are now completing a revision to the project that will make this engaging virtual exploration accessible to a much larger audience. With minor modifications we will be able to put the exhibit onto the world wide web so that any person with internet access can view and learn about exciting volcanic and hydrothermal activity at Axial Seamount on the Juan de Fuca Ridge. The modifications address some cosmetic and logistic ISSUES confronted in the museum environment, but will mainly involve compressing video clips so they can be delivered more efficiently over the internet. The web version, like the museum version, will allow users to choose from 1 of 3 different dives sites in the caldera of Axial Volcano. The dives are based on real seafloor settings at Axial seamount, an active submarine volcano on the Juan de Fuca Ridge (NE Pacific) that is also the location of a seafloor observatory called NeMO. Once a dive is chosen, then the user watches ROPOS being deployed and then arrives into a 3-D computer-generated seafloor environment that is based on the real world but is easier to visualize and navigate. Once on the bottom, the user is placed within a 360 degree panorama and can look in all directions by manipulating the computer mouse. By clicking on markers embedded in the scene, the user can then either move to other panorama locations via movies that travel through the 3-D virtual environment, or they can play video clips from actual ROPOS dives specifically related to that scene. Audio accompanying the video clips informs the user where they are

  3. Physiological constraints and energetic costs of diving behaviour in marine mammals: a review of studies using trained Steller sea lions diving in the open ocean.

    Science.gov (United States)

    Rosen, David A S; Hindle, Allyson G; Gerlinsky, Carling D; Goundie, Elizabeth; Hastie, Gordon D; Volpov, Beth L; Trites, Andrew W

    2017-01-01

    Marine mammals are characterized as having physiological specializations that maximize the use of oxygen stores to prolong time spent under water. However, it has been difficult to undertake the requisite controlled studies to determine the physiological limitations and trade-offs that marine mammals face while diving in the wild under varying environmental and nutritional conditions. For the past decade, Steller sea lions (Eumetopias jubatus) trained to swim and dive in the open ocean away from the physical confines of pools participated in studies that investigated the interactions between diving behaviour, energetic costs, physiological constraints, and prey availability. Many of these studies measured the cost of diving to understand how it varies with behaviour and environmental and physiological conditions. Collectively, these studies show that the type of diving (dive bouts or single dives), the level of underwater activity, the depth and duration of dives, and the nutritional status and physical condition of the animal affect the cost of diving and foraging. They show that dive depth, dive and surface duration, and the type of dive result in physiological adjustments (heart rate, gas exchange) that may be independent of energy expenditure. They also demonstrate that changes in prey abundance and nutritional status cause sea lions to alter the balance between time spent at the surface acquiring oxygen (and offloading CO2 and other metabolic by-products) and time spent at depth acquiring prey. These new insights into the physiological basis of diving behaviour further our understanding of the potential scope for behavioural responses of marine mammals to environmental changes, the energetic significance of these adjustments, and the consequences of approaching physiological limits.

  4. Probing the limits of human deep diving.

    Science.gov (United States)

    Bennett, P B; McLeod, M

    1984-01-07

    Divers breathing compressed air are restricted to 45 m depth because of the narcotic effects of nitrogen and toxic action of oxygen at increased pressures. Substitution of oxygen-helium for compressed air has permitted divers to reach 600 m. However, at depths greater than 160 m, signs and symptoms of the high pressure nervous syndrome (h.p.n.s.) occur, with tremors, myoclonic jerking, nausea, vomiting, fatigue, somnolence, e.e.g. changes, dyspnoea, and poor sleep with nightmares. It has been the objective of this Laboratory to ameliorate the symptoms of pressure-induced h.p.n.s. by the addition of small amounts of 'narcotic' nitrogen to the oxygen-helium mixture to form the Trimix breathing gas. In 1973, comparative experiments with oxygen-helium and the same divers, during compressions in only 33 min to 219.5 m and 305 m, showed such Trimix to be effective with 10% (by volume) nitrogen. Simulated dives, termed ATLANTIS, have been made with Trimix over the last 4 years to depths in excess of 610 m for 11 days, 650 m for 4 days and 686 m for 1 day. The objectives were to determine the effects of either slow or rapid rates of compression, and either 5% or 10% (by volume) nitrogen in Heliox, on the presence of h.p.n.s. or nitrogen narcosis. Measurements were made of intellectual and psychomotor performance, electrophysiological function of the brain and reflexes, lung and cardiovascular function, including arterial gas analysis at rest and work, blood chemistry and psychiatric and psychological status. The results permit the conclusion that divers may be compressed safely to depths as great as 686 m. The technique requires a slow exponential compression over days, with frequent stages lasting 14 h or more, the use of 5-8% (by volume) nitrogen in Heliox and careful selection of the divers.

  5. 29 CFR Appendix B to Subpart Y of... - Guidelines for Scientific Diving

    Science.gov (United States)

    2010-07-01

    ... 29 Labor 8 2010-07-01 2010-07-01 false Guidelines for Scientific Diving B Appendix B to Subpart Y... ADMINISTRATION, DEPARTMENT OF LABOR (CONTINUED) SAFETY AND HEALTH REGULATIONS FOR CONSTRUCTION Diving Pt. 1926, Subpt. Y, App. B Appendix B to Subpart Y of Part 1926—Guidelines for Scientific Diving Note: The...

  6. Deep-Diving California Sea Lions: Are They Pushing Their Physiological Limit?

    Science.gov (United States)

    2014-09-30

    bradycardia during descent occurs in deep-diving emperor penguins (Wright et al. 2014), and in deep-diving bottlenose dolphins ( Tursiops truncatus ...Experimental Biology 210: 278-289. Williams, T.M., J.E. Haun and W.A. Friedl. 1999. The diving physiology of bottlenose dolphins ( Tursiops truncatus ). I

  7. Blood Oxygen Conservation in Diving Sea Lions: How Low Does Oxygen Really Go

    Science.gov (United States)

    2015-09-30

    descent occurs in deep-diving emperor penguins (Ponganis, unpublished data), and in deep-diving bottlenose dolphins ( Tursiops truncatus ), which also dive...dolphins ( Tursiops truncatus ). I. Balancing the demands of exercise for energy conservation at depth. Journal of Experimental Biology 202: 2739-2748.

  8. THE PROCEDURE BY EVALUATION OF DIVERS FOR THE DEEP DIVING

    Directory of Open Access Journals (Sweden)

    Mihai DIACONU

    2014-05-01

    Full Text Available When a diver is selected to perform a deep diving course, he has to pass a medical test and isn’t affected by the HPNS (High Pressure Nervous Syndrome. When a diver is selected to perform a deep diving course, he has to pass an evaluation stage in order to prove his ability to tolerate the compression speed accompanied by the helium - oxygen breathing mixture without encountering the HPNS effects. The deep diving test consists in postural tremor and the EEG registration, in both conditions: at the atmospheric pressure and at 180 m deep too. Then the results obtained at the surface percentage limits are fixed for the maximum deflection agreed between the values registration made under pressure and the atmospheric pressure (surface values.

  9. 48 CFR 252.225-7010 - Commercial Derivative Military Article-Specialty Metals Compliance Certificate.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 3 2010-10-01 2010-10-01 false Commercial Derivative... SOLICITATION PROVISIONS AND CONTRACT CLAUSES Text of Provisions And Clauses 252.225-7010 Commercial Derivative... provision: Commercial Derivative Military Article—Specialty Metals Compliance Certificate (JUL 2009) (a...

  10. Underwater and Dive Station Work-Site Noise Surveys

    Science.gov (United States)

    2008-03-14

    ANU magnetic hydraulic drill press was used to extract coupons for this project. The drill press was powered by a hydraulic pressure unit ( HPU ...craft (Figure 6) as the diving platform with the HPU located aft approximately 15 feet from dive station on the starboard side of the boathouse. The...minutes yielded a total in- water noise dose of 45.7%. In air exposure to the HPU for the operator 1-2 feet from the unit was 100 dB (A) re 20µPa

  11. Seabird diving behaviour reveals the functional significance of shelf-sea fronts as foraging hotspots

    Science.gov (United States)

    Cox, S. L.; Miller, P. I.; Embling, C. B.; Scales, K. L.; Bicknell, A. W. J.; Hosegood, P. J.; Morgan, G.; Ingram, S. N.; Votier, S. C.

    2016-09-01

    Oceanic fronts are key habitats for a diverse range of marine predators, yet how they influence fine-scale foraging behaviour is poorly understood. Here, we investigated the dive behaviour of northern gannets Morus bassanus in relation to shelf-sea fronts. We GPS (global positioning system) tracked 53 breeding birds and examined the relationship between 1901 foraging dives (from time-depth recorders) and thermal fronts (identified via Earth Observation composite front mapping) in the Celtic Sea, Northeast Atlantic. We (i) used a habitat-use availability analysis to determine whether gannets preferentially dived at fronts, and (ii) compared dive characteristics in relation to fronts to investigate the functional significance of these oceanographic features. We found that relationships between gannet dive probabilities and fronts varied by frontal metric and sex. While both sexes were more likely to dive in the presence of seasonally persistent fronts, links to more ephemeral features were less clear. Here, males were positively correlated with distance to front and cross-front gradient strength, with the reverse for females. Both sexes performed two dive strategies: shallow V-shaped plunge dives with little or no active swim phase (92% of dives) and deeper U-shaped dives with an active pursuit phase of at least 3 s (8% of dives). When foraging around fronts, gannets were half as likely to engage in U-shaped dives compared with V-shaped dives, independent of sex. Moreover, V-shaped dive durations were significantly shortened around fronts. These behavioural responses support the assertion that fronts are important foraging habitats for marine predators, and suggest a possible mechanistic link between the two in terms of dive behaviour. This research also emphasizes the importance of cross-disciplinary research when attempting to understand marine ecosystems.

  12. Perceptions amongst Tasmanian recreational scuba divers of the value of a diving medical.

    Science.gov (United States)

    Baines, Carol

    2013-12-01

    An online survey was offered to recreational divers in Tasmania to ascertain if they have an understanding of how pressure affects their health and if they considered an annual dive medical necessary. A total of 98 recreational divers completed the survey, five of these had never had a dive medical while 74 felt that if they passed their dive medical they do not have any potential illness. Sixty five saw the dive medical as a comprehensive health check. This project provided an insight to Tasmanian recreational divers' understanding of and attitude towards the value of a dive medical.

  13. Persistent (patent) foramen ovale (PFO): implications for safe diving.

    Science.gov (United States)

    Germonpré, Peter

    2015-06-01

    Diving medicine is a peculiar specialty. There are physicians and scientists from a wide variety of disciplines with an interest in diving and who all practice 'diving medicine': the study of the complex whole-body physiological changes and interactions upon immersion and emersion. To understand these, the science of physics and molecular gas and fluid movements comes into play. The ultimate goal of practicing diving medicine is to preserve the diver's health, both during and after the dive. Good medicine starts with prevention. For most divers, underwater excursions are not a professional necessity but a hobby; avoidance of risk is generally a much better option than risk mitigation or cure. However, prevention of diving illnesses seems to be even more difficult than treating those illnesses. The papers contained in this issue of DHM are a nice mix of various aspects of PFO that divers are interested in, all of them written by specialist doctors who are avid divers themselves. However, diving medicine should also take advantage of research from the "non-diving" medicine community, and PFO is a prime example. Cardiology and neurology have studied PFO for as long, or even longer than divers have been the subjects of PFO research, and with much greater numbers and resources. Unexplained stroke has been associated with PFO, as has severe migraine with aura. As the association seems to be strong, investigating the effect of PFO closure was a logical step. Devices have been developed and perfected, allowing now for a relatively low-risk procedure to 'solve the PFO problem'. However, as with many things in science, the results have not been as spectacular as hoped for: patients still get recurrences of stroke, still have migraine attacks. The risk-benefit ratio of PFO closure for these non-diving diseases is still debated. For diving, we now face a similar problem. Let there be no doubt that PFO is a pathway through which venous gas emboli (VGE) can arterialize, given

  14. Detection of venous gas emboli after repetitive breath-hold dives: case report.

    Science.gov (United States)

    Cialoni, D; Pieri, M; Giunchi, G; Sponsiello, N; Lanzone, A M; Torcello, L; Boaretto, G; Marroni, A

    2016-01-01

    Neurological symptoms after breathhold (BH) diving are often referred to as "Taravana" and considered a form of decompression sickness. However, the presence of "high" gas embolism after BH diving has never been clearly shown. This study showed high bubble formation after BH diving. We performed transthoracic echocardiography on a 53-year-old male spearfishing diver (180 cm; 80 kg; BMI 24.7) 15 minutes before diving and at 15-minute intervals for 90 minutes after diving in a 42-meter-deep pool. Number of dives, bottom time and surface intervals were freely determined by the diver. Dive profiles were digitally recorded for depth, time and surface interval, using a freediving computer. Relative surface interval (surface interval/diving time) and gradient factor were calculated. High bubble grades were found in all the recorded echocardiograms. From the first to third recording (45 minutes), Grade 4 Eftedal-Brubakk (EB) bubbles were observed. The 60-, 75- and 90-minute recordings showed a reduction to Grades 3, 2 and 1 EB. Mean calculated GF for every BH dive was 0.22; maximum GF after the last dive was 0.33. High bubble grades can occur in BH diving, as confirmed by echocardiographic investigation. Ordinary methods to predict inert gas supersaturation may not able to predict Taravana cases.

  15. Analysis of dynamics and fit of diving suits

    Science.gov (United States)

    Mahnic Naglic, M.; Petrak, S.; Gersak, J.; Rolich, T.

    2017-10-01

    Paper presents research on dynamical behaviour and fit analysis of customised diving suits. Diving suits models are developed using the 3D flattening method, which enables the construction of a garment model directly on the 3D computer body model and separation of discrete 3D surfaces as well as transformation into 2D cutting parts. 3D body scanning of male and female test subjects was performed with the purpose of body measurements analysis in static and dynamic postures and processed body models were used for construction and simulation of diving suits prototypes. All necessary parameters, for 3D simulation were applied on obtained cutting parts, as well as parameters values for mechanical properties of neoprene material. Developed computer diving suits prototypes were used for stretch analysis on areas relevant for body dimensional changes according to dynamic anthropometrics. Garment pressures against the body in static and dynamic conditions was also analysed. Garments patterns for which the computer prototype verification was conducted were used for real prototype production. Real prototypes were also used for stretch and pressure analysis in static and dynamic conditions. Based on the obtained results, correlation analysis between body changes in dynamic positions and dynamic stress, determined on computer and real prototypes, was performed.

  16. A Measurement of "g" Using Alexander's Diving Bell

    Science.gov (United States)

    Quiroga, M.; Martinez, S.; Otranto, S.

    2010-01-01

    This paper describes a very simple exercise using an inverted test tube pushed straight down into a column of water to determine the free-fall acceleration "g". The exercise employs the ideal gas law and only involves the measurement of the displacement of the bottom of the "diving bell" and the water level inside the tube with respect to the…

  17. Diving behaviour of African penguins: do they differ from other ...

    African Journals Online (AJOL)

    African penguins Spheniscus demersus closely resemble Magellanic S. magellanicus and Humboldt S. humboldti penguins and have similar breeding and feeding ecologies. Adults feed on pelagic schooling fish in continental shelf waters, but African penguins have been reported to have shallower dive angles and remain ...

  18. Doppler Bubble Grades After Diving and Relevance of Body Fat

    NARCIS (Netherlands)

    Schellart, Nico A. M.; Vellinga, Tjeerd P. van Rees; Van Dijk, Frank J.; Sterk, Wouter

    2012-01-01

    SCHELLART NAM, VAN REES VELLINGA TP, VAN DIJK FJ, STERK W. Doppler bubble grades after diving and relevance of body fat. Aviat Space Environ Med 2012; 83:951-7. Background: From the literature on venous gas embolism (VGE) and decompression sickness (DCS), it remains unclear whether body fat is a

  19. Chromosomal analysis of some Egyptian diving beetles (Coleoptera ...

    African Journals Online (AJOL)

    Chromosomal analysis of some Egyptian diving beetles (Coleoptera: Dytiscidae). Rowaida Saleh Ahmed”, Robert B Angusz, Samy Zalatl and Fatma Shaarawi3. 1. Department of Zoology, Faculty of Science, Suez Canal University, lsmailia, Egypt. 2. Division of Biology, Royal Holloway, University of London, Egham, Surrey, ...

  20. Diving for dope” : Controlling underwater drug trafficking

    NARCIS (Netherlands)

    Eski, Y.

    2017-01-01

    This paper will offer an ethnographic account of the everyday reality of controlling illegal underwater drug trafficking in the global Port of Rotterdam (PoR). In so doing, it will explore what it means for customs diving officers to do drug inspections under challenging circumstances in order to

  1. Scuba diving injuries among Divers Alert Network members 2010-2011.

    Science.gov (United States)

    Ranapurwala, Shabbar I; Bird, Nicholas; Vaithiyanathan, Pachabi; Denoble, Petar J

    2014-06-01

    Scuba diving injuries vary greatly in severity and prognosis. While decompression sickness (DCS) and arterial gas embolism can be tracked easily, other forms of diving injury remain unaccounted for. The purpose of this paper is to assess rates of overall self-reported scuba-diving-related injuries, self-reported DCS-like symptoms, and treated DCS and their association with diver certification level, diving experience and demographic factors. We analyzed self-reported data from a Divers Alert Network membership health survey conducted during the summer of 2011. Poisson regression models with scaled deviance were used to model the relative rates of reported injuries. Models were adjusted for sex, age, body mass index (BMI) and average annual dives, based on the bias-variance tradeoff. The overall rate of diving-related injury was 3.02 per 100 dives, self-reported DCS symptoms was 1.55 per 1,000 dives and treated DCS was 5.72 per 100,000 dives. Diving-related injury and self-reported DCS symptom rates decreased for higher diver certification levels, increasing age, increasing number of average annual dives and for men; they increased for increasing BMI. Diving injury rates may be higher than previously thought, indicating a greater burden on the diving community. Self-reported DCS-like symptoms are a small fraction of all dive-related injuries and those receiving treatment for DCS are an even smaller fraction. The small number of divers seeking treatment may suggest the mild nature and a tendency towards natural resolution for most injuries.

  2. Diving-flight aerodynamics of a peregrine falcon (Falco peregrinus).

    Science.gov (United States)

    Ponitz, Benjamin; Schmitz, Anke; Fischer, Dominik; Bleckmann, Horst; Brücker, Christoph

    2014-01-01

    This study investigates the aerodynamics of the falcon Falco peregrinus while diving. During a dive peregrines can reach velocities of more than 320 km h⁻¹. Unfortunately, in freely roaming falcons, these high velocities prohibit a precise determination of flight parameters such as velocity and acceleration as well as body shape and wing contour. Therefore, individual F. peregrinus were trained to dive in front of a vertical dam with a height of 60 m. The presence of a well-defined background allowed us to reconstruct the flight path and the body shape of the falcon during certain flight phases. Flight trajectories were obtained with a stereo high-speed camera system. In addition, body images of the falcon were taken from two perspectives with a high-resolution digital camera. The dam allowed us to match the high-resolution images obtained from the digital camera with the corresponding images taken with the high-speed cameras. Using these data we built a life-size model of F. peregrinus and used it to measure the drag and lift forces in a wind-tunnel. We compared these forces acting on the model with the data obtained from the 3-D flight path trajectory of the diving F. peregrinus. Visualizations of the flow in the wind-tunnel uncovered details of the flow structure around the falcon's body, which suggests local regions with separation of flow. High-resolution pictures of the diving peregrine indicate that feathers pop-up in the equivalent regions, where flow separation in the model falcon occurred.

  3. Diving-flight aerodynamics of a peregrine falcon (Falco peregrinus.

    Directory of Open Access Journals (Sweden)

    Benjamin Ponitz

    Full Text Available This study investigates the aerodynamics of the falcon Falco peregrinus while diving. During a dive peregrines can reach velocities of more than 320 km h⁻¹. Unfortunately, in freely roaming falcons, these high velocities prohibit a precise determination of flight parameters such as velocity and acceleration as well as body shape and wing contour. Therefore, individual F. peregrinus were trained to dive in front of a vertical dam with a height of 60 m. The presence of a well-defined background allowed us to reconstruct the flight path and the body shape of the falcon during certain flight phases. Flight trajectories were obtained with a stereo high-speed camera system. In addition, body images of the falcon were taken from two perspectives with a high-resolution digital camera. The dam allowed us to match the high-resolution images obtained from the digital camera with the corresponding images taken with the high-speed cameras. Using these data we built a life-size model of F. peregrinus and used it to measure the drag and lift forces in a wind-tunnel. We compared these forces acting on the model with the data obtained from the 3-D flight path trajectory of the diving F. peregrinus. Visualizations of the flow in the wind-tunnel uncovered details of the flow structure around the falcon's body, which suggests local regions with separation of flow. High-resolution pictures of the diving peregrine indicate that feathers pop-up in the equivalent regions, where flow separation in the model falcon occurred.

  4. Recursive filtering for zero offset correction of diving depth time series with GNU R package diveMove.

    Directory of Open Access Journals (Sweden)

    Sebastián P Luque

    Full Text Available Zero offset correction of diving depth measured by time-depth recorders is required to remove artifacts arising from temporal changes in accuracy of pressure transducers. Currently used methods for this procedure are in the proprietary software domain, where researchers cannot study it in sufficient detail, so they have little or no control over how their data were changed. GNU R package diveMove implements a procedure in the Free Software domain that consists of recursively smoothing and filtering the input time series using moving quantiles. This paper describes, demonstrates, and evaluates the proposed method by using a "perfect" data set, which is subsequently corrupted to provide input for the proposed procedure. The method is evaluated by comparing the corrected time series to the original, uncorrupted, data set from an Antarctic fur seal (Arctocephalus gazella Peters, 1875. The Root Mean Square Error of the corrected data set, relative to the "perfect" data set, was nearly identical to the magnitude of noise introduced into the latter. The method, thus, provides a flexible, reliable, and efficient mechanism to perform zero offset correction for analyses of diving behaviour. We illustrate applications of the method to data sets from four species with large differences in diving behaviour, measured using different sampling protocols and instrument characteristics.

  5. Commercializing Patents

    National Research Council Canada - National Science Library

    Ted Sichelman

    2010-01-01

    .... Although more recent "prospect" theories properly recognize the importance of patent protection for commercializing inventions, they incorrectly conclude that strong, real property-like rights...

  6. 45 CFR 74.48 - Contract provisions.

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Contract provisions. 74.48 Section 74.48 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION UNIFORM ADMINISTRATIVE REQUIREMENTS FOR AWARDS AND SUBAWARDS TO INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, OTHER NONPROFIT ORGANIZATIONS, AND COMMERCIAL ORGANIZATIONS Post-Award...

  7. Turkish recreational divers: a comparative study of their demographics, diving habits, health and attitudes towards safety.

    Science.gov (United States)

    Mirasoglu, Bengusu; Aktas, Samil

    2017-09-01

    In Turkey, scuba diving has become more popular and accessible in the past decade and there has been a commensurate rise in the number of certified divers. This new generation of recreational divers has not been described in detail previously. The aim of this study was to profile this group, while investigating any gender differences and making comparisons with the global diving community. Turkish dive club members and diving forum⁄blog readers were invited to complete an online questionnaire investigating their demography, medical issues and diving history and habits. The questionnaire was completed by 303 female and 363 male divers. Significant differences were found between the sexes in terms of demographics, diving experience and attitudes toward safety. Previous or ongoing medical conditions were reported by 100 female divers and 141 males. Only 29% of females and 22% of males had been examined by a physician trained to conduct assessments of fitness to dive. Female divers did not report problems while diving during menstruation or while taking oral contraceptives. There was no significant difference in the occurrence of decompression sickness (DCS) and DCS-like symptoms between the sexes. This is the largest study to date conducted on recreational divers in Turkey and so carries some value. It profiles their physical and behavioral attributes as well as differences in diving practices between the sexes in Turkey. Our findings should have implications for medical screening and dive training standards.

  8. Argon used as dry suit insulation gas for cold-water diving

    Science.gov (United States)

    2013-01-01

    Background Cold-water diving requires good thermal insulation because hypothermia is a serious risk. Water conducts heat more efficiently compared to air. To stay warm during a dive, the choice of thermal protection should be based on physical activity, the temperature of the water, and the duration of exposure. A dry suit, a diving suit filled with gas, is the most common diving suit in cold water. Air is the traditional dry suit inflation gas, whereas the thermal conductivity of argon is approximately 32% lower compared to that of air. This study evaluates the benefits of argon, compared to air, as a thermal insulation gas for a dry suit during a 1-h cold-water dive by divers of the Royal Netherlands Navy. Methods Seven male Special Forces divers made (in total) 19 dives in a diving basin with water at 13°C at a depth of 3 m for 1 h in upright position. A rubber dry suit and woollen undergarment were used with either argon (n = 13) or air (n = 6) (blinded to the divers) as suit inflation gas. Core temperature was measured with a radio pill during the dive. Before, halfway, and after the dive, subjective thermal comfort was recorded using a thermal comfort score. Results No diver had to abort the test due to cold. No differences in core temperature and thermal comfort score were found between the two groups. Core temperature remained unchanged during the dives. Thermal comfort score showed a significant decrease in both groups after a 60-min dive compared to baseline. Conclusions In these tests the combination of the dry suit and undergarment was sufficient to maintain core temperature and thermal comfort for a dive of 1 h in water at 13°C. The use of argon as a suit inflation gas had no added value for thermal insulation compared to air for these dives. PMID:24438580

  9. Competitive apnea diving sessions induces an adaptative antioxidant response in mononucleated blood cells.

    Science.gov (United States)

    Sureda, A; Batle, J M; Tur, J A; Pons, A

    2015-09-01

    The aim was evaluating the effects of hypoxia/reoxygenation repetitive episodes during 5 days of apnea diving (3-day training/2-day competition) on peripheral blood mononuclear cells (PBMCs) antioxidant defenses, oxidative damage, and plasma xanthine oxidase activity. Blood samples, from seven professional apnea divers, were taken under basal conditions the previous morning to the first training session (pre-diving basal), 4 h after ending the competition (4 h post-diving) and the following morning (15 h after last dive) in basal conditions (post-diving basal). Glucose levels significantly decreased whereas triglycerides increased at 4 h post-diving, both returning to basal values at post-diving basal. Glutathione reductase and catalase activity significantly increased after 4 h post-diving remaining elevated at post-diving basal. Glutathione peroxidase and superoxide dismutase activities and catalase protein levels progressively increased after diving with significant differences respect to initial values at post-diving basal. No significant differences were observed in circulating PBMCs and oxidative damage markers. Plasma xanthine oxidase activity and nitrite levels, but not the inducible nitric oxide synthetase, significantly increased 4 h post-diving, returning to the basal values after 15 h. In conclusion, chronic and repetitive episodes of diving apnea during five consecutive days increased plasma xanthine oxidase activity and nitric oxide production which could enhance the signalling role of reactive oxygen and nitrogen species for PBMCs antioxidant adaptation against hypoxia/reoxygenation.

  10. Investigating Annual Diving Behaviour by Hooded Seals (Cystophora cristata) within the Northwest Atlantic Ocean

    Science.gov (United States)

    Andersen, Julie M.; Skern-Mauritzen, Mette; Boehme, Lars; Wiersma, Yolanda F.; Rosing-Asvid, Aqqalu; Hammill, Mike O.; Stenson, Garry B.

    2013-01-01

    With the exception of relatively brief periods when they reproduce and moult, hooded seals, Cystophora cristata, spend most of the year in the open ocean where they undergo feeding migrations to either recover or prepare for the next fasting period. Valuable insights into habitat use and diving behaviour during these periods have been obtained by attaching Satellite Relay Data Loggers (SRDLs) to 51 Northwest (NW) Atlantic hooded seals (33 females and 18 males) during ice-bound fasting periods (2004−2008). Using General Additive Models (GAMs) we describe habitat use in terms of First Passage Time (FPT) and analyse how bathymetry, seasonality and FPT influence the hooded seals’ diving behaviour described by maximum dive depth, dive duration and surface duration. Adult NW Atlantic hooded seals exhibit a change in diving activity in areas where they spend >20 h by increasing maximum dive depth, dive duration and surface duration, indicating a restricted search behaviour. We found that male and female hooded seals are spatially segregated and that diving behaviour varies between sexes in relation to habitat properties and seasonality. Migration periods are described by increased dive duration for both sexes with a peak in May, October and January. Males demonstrated an increase in dive depth and dive duration towards May (post-breeding/pre-moult) and August–October (post-moult/pre-breeding) but did not show any pronounced increase in surface duration. Females dived deepest and had the highest surface duration between December and January (post-moult/pre-breeding). Our results suggest that the smaller females may have a greater need to recover from dives than that of the larger males. Horizontal segregation could have evolved as a result of a resource partitioning strategy to avoid sexual competition or that the energy requirements of males and females are different due to different energy expenditure during fasting periods. PMID:24282541

  11. Argon used as dry suit insulation gas for cold-water diving.

    Science.gov (United States)

    Vrijdag, Xavier Ce; van Ooij, Pieter-Jan Am; van Hulst, Robert A

    2013-06-03

    Cold-water diving requires good thermal insulation because hypothermia is a serious risk. Water conducts heat more efficiently compared to air. To stay warm during a dive, the choice of thermal protection should be based on physical activity, the temperature of the water, and the duration of exposure. A dry suit, a diving suit filled with gas, is the most common diving suit in cold water. Air is the traditional dry suit inflation gas, whereas the thermal conductivity of argon is approximately 32% lower compared to that of air. This study evaluates the benefits of argon, compared to air, as a thermal insulation gas for a dry suit during a 1-h cold-water dive by divers of the Royal Netherlands Navy. Seven male Special Forces divers made (in total) 19 dives in a diving basin with water at 13 degrees C at a depth of 3 m for 1 h in upright position. A rubber dry suit and woollen undergarment were used with either argon (n = 13) or air (n = 6) (blinded to the divers) as suit inflation gas. Core temperature was measured with a radio pill during the dive. Before, halfway, and after the dive, subjective thermal comfort was recorded using a thermal comfort score. No diver had to abort the test due to cold. No differences in core temperature and thermal comfort score were found between the two groups. Core temperature remained unchanged during the dives. Thermal comfort score showed a significant decrease in both groups after a 60-min dive compared to baseline. In these tests the combination of the dry suit and undergarment was sufficient to maintain core temperature and thermal comfort for a dive of 1h in water at 13 degrees C. The use of argon as a suit inflation gas had no added value for thermal insulation compared to air for these dives.

  12. Investigating annual diving behaviour by hooded seals (Cystophora cristata within the Northwest Atlantic Ocean.

    Directory of Open Access Journals (Sweden)

    Julie M Andersen

    Full Text Available With the exception of relatively brief periods when they reproduce and moult, hooded seals, Cystophora cristata, spend most of the year in the open ocean where they undergo feeding migrations to either recover or prepare for the next fasting period. Valuable insights into habitat use and diving behaviour during these periods have been obtained by attaching Satellite Relay Data Loggers (SRDLs to 51 Northwest (NW Atlantic hooded seals (33 females and 18 males during ice-bound fasting periods (2004-2008. Using General Additive Models (GAMs we describe habitat use in terms of First Passage Time (FPT and analyse how bathymetry, seasonality and FPT influence the hooded seals' diving behaviour described by maximum dive depth, dive duration and surface duration. Adult NW Atlantic hooded seals exhibit a change in diving activity in areas where they spend >20 h by increasing maximum dive depth, dive duration and surface duration, indicating a restricted search behaviour. We found that male and female hooded seals are spatially segregated and that diving behaviour varies between sexes in relation to habitat properties and seasonality. Migration periods are described by increased dive duration for both sexes with a peak in May, October and January. Males demonstrated an increase in dive depth and dive duration towards May (post-breeding/pre-moult and August-October (post-moult/pre-breeding but did not show any pronounced increase in surface duration. Females dived deepest and had the highest surface duration between December and January (post-moult/pre-breeding. Our results suggest that the smaller females may have a greater need to recover from dives than that of the larger males. Horizontal segregation could have evolved as a result of a resource partitioning strategy to avoid sexual competition or that the energy requirements of males and females are different due to different energy expenditure during fasting periods.

  13. Investigating annual diving behaviour by hooded seals (Cystophora cristata) within the Northwest Atlantic Ocean.

    Science.gov (United States)

    Andersen, Julie M; Skern-Mauritzen, Mette; Boehme, Lars; Wiersma, Yolanda F; Rosing-Asvid, Aqqalu; Hammill, Mike O; Stenson, Garry B

    2013-01-01

    With the exception of relatively brief periods when they reproduce and moult, hooded seals, Cystophora cristata, spend most of the year in the open ocean where they undergo feeding migrations to either recover or prepare for the next fasting period. Valuable insights into habitat use and diving behaviour during these periods have been obtained by attaching Satellite Relay Data Loggers (SRDLs) to 51 Northwest (NW) Atlantic hooded seals (33 females and 18 males) during ice-bound fasting periods (2004-2008). Using General Additive Models (GAMs) we describe habitat use in terms of First Passage Time (FPT) and analyse how bathymetry, seasonality and FPT influence the hooded seals' diving behaviour described by maximum dive depth, dive duration and surface duration. Adult NW Atlantic hooded seals exhibit a change in diving activity in areas where they spend >20 h by increasing maximum dive depth, dive duration and surface duration, indicating a restricted search behaviour. We found that male and female hooded seals are spatially segregated and that diving behaviour varies between sexes in relation to habitat properties and seasonality. Migration periods are described by increased dive duration for both sexes with a peak in May, October and January. Males demonstrated an increase in dive depth and dive duration towards May (post-breeding/pre-moult) and August-October (post-moult/pre-breeding) but did not show any pronounced increase in surface duration. Females dived deepest and had the highest surface duration between December and January (post-moult/pre-breeding). Our results suggest that the smaller females may have a greater need to recover from dives than that of the larger males. Horizontal segregation could have evolved as a result of a resource partitioning strategy to avoid sexual competition or that the energy requirements of males and females are different due to different energy expenditure during fasting periods.

  14. Sperm whale dive behavior characteristics derived from intermediate-duration archival tag data.

    Science.gov (United States)

    Irvine, Ladd; Palacios, Daniel M; Urbán, Jorge; Mate, Bruce

    2017-10-01

    Here, we describe the diving behavior of sperm whales (Physeter macrocephalus) using the Advanced Dive Behavior (ADB) tag, which records depth data at 1-Hz resolution and GPS-quality locations for over 1 month, before releasing from the whale for recovery. A total of 27 ADB tags were deployed on sperm whales in the central Gulf of California, Mexico, during spring 2007 and 2008, of which 10 were recovered for data download. Tracking durations of all tags ranged from 0 to 34.5 days (median = 2.3 days), and 0.6 to 26.6 days (median = 5.0 days) for recovered tags. Recovered tags recorded a median of 50.8 GPS-quality locations and 42.6 dives per day. Dive summary metrics were generated for archived dives and were subsequently classified into six categories using hierarchical cluster analysis. A mean of 77% of archived dives per individual were one of four dive categories with median Maximum Dive Depth >290 m (V-shaped, Mid-water, Benthic, or Variable), likely associated with foraging. Median Maximum Dive Depth was whales remained near the tagging area during the tracking period, but one moved north of Isla Tiburón, where it appeared to regularly dive to, and travel along the seafloor. Three whales were tagged on the same day in 2007 and subsequently traveled in close proximity (<1 km) for 2 days. During this period, the depth and timing of their dives were not coordinated, suggesting they were foraging on a vertically heterogeneous prey field. The multiweek dive records produced by ADB tags enabled us to generate a robust characterization of the diving behavior, activity budget, and individual variation for an important predator of the mesopelagos over temporal and spatial scales not previously possible.

  15. Seagrass Importance in Food Provisioning Services: Fish Stomach ...

    African Journals Online (AJOL)

    i.e. the human benefits from those) are elusive. In this paper, the food provisioning service of seagrass meadows is operationalized through the study of the stomach contents of 13 important commercial fish species in. Chwaka Bay, Zanzibar.

  16. Provisional Crown Dislodgement during Scuba Diving: A Case of Barotrauma

    Directory of Open Access Journals (Sweden)

    Meenal Nitin Gulve

    2013-01-01

    Full Text Available Changes in ambient pressure, for example, during flying, diving, or hyperbaric oxygen therapy, can lead to barotrauma. Although it may seem that this issue was neglected in dental education and research in recent decades, familiarity with and understanding of these facts may be of importance for dental practitioners. We report the case of a patient who experienced barotrauma involving dislodgement of a provisional crown during scuba diving. Patients who are exposed to pressure changes as a part of their jobs or hobbies and their dentists should know the causes of barotrauma. In addition, the clinician must be aware of the possible influence of pressure changes on the retention of dental components.

  17. Passive acoustic detection of deep-diving beaked whales

    DEFF Research Database (Denmark)

    Zimmer, W.M.X.; Harwood, J.; Tyack, P.L.

    2008-01-01

    Beaked whales can remain submerged for an hour or more and are difficult to sight when they come to the surface to breathe. Passive acoustic detection (PAD) not only complements traditional visual-based methods for detecting these species but also can be more effective because beaked whales produce...... clicks regularly to echolocate on prey during deep foraging dives. The effectiveness of PAD for beaked whales depends not only on the acoustic behavior and output of the animals but also on environmental conditions and the quality of the passive sonar implemented. A primary constraint on the range....../s, a receiver close to the surface should be able to detect acoustically Cuvier's beaked whales with a high probability at distances up to 0.7  km, provided the listening duration exceeds the deep dive interval, about 2.5  h on average. Detection ranges beyond 4  km are unlikely and would require low ambient...

  18. A Review of SCUBA Diving Impacts and Implication for Coral Reefs Conservation and Tourism Management

    Directory of Open Access Journals (Sweden)

    Zainal Abidin Siti Zulaiha

    2014-01-01

    Full Text Available Dive tourism has become important in term of magnitude and significantly contributes to regional economies. Nevertheless, in the absence of proper controls and enforcement, unplanned tourism growth has caused environmental degradation which undermines the long-term sustainability of the tourism industry. The purpose of this paper is to explore factors that contribute to the SCUBA diving impacts on coral and fish communities. This paper explains the causes of a certain event, validating the problem of impacts, defining the core issues and identifies possible causes leading to an effect. The phenomenon of diving impacts on coral reefs is a result of intensive use of dive site over the long-term. The divers can reduce their impacts towards coral reefs through responsible diving behaviors. The causes of cumulative diver’s contacts are more complicated than it seems. In response, this paper proposes the best mitigation strategies that need to be considered for future dive tourism management.

  19. Comparative histology of muscle in free ranging cetaceans: shallow versus deep diving species.

    Science.gov (United States)

    Sierra, E; Fernández, A; Espinosa de los Monteros, A; Díaz-Delgado, J; Bernaldo de Quirós, Y; García-Álvarez, N; Arbelo, M; Herráez, P

    2015-10-30

    Different marine mammal species exhibit a wide range of diving behaviour based on their breath-hold diving capabilities. They are classically categorized as long duration, deep-diving and short duration, shallow-diving species. These abilities are likely to be related to the muscle characteristics of each species. Despite the increasing number of publications on muscle profile in different cetacean species, very little information is currently available concerning the characteristics of other muscle components in these species. In this study, we examined skeletal muscle fiber type, fiber size (cross sectional area and lesser diameter), intramuscular substrates, and perimysium-related structures, by retrospective study in 146 stranded cetaceans involving 15 different species. Additionally, we investigated diving profile-specific histological features. Our results suggest that deep diving species have higher amount of intramyocyte lipid droplets, and evidence higher percentage of intramuscular adipose tissue, and larger fibre sizes in this group of animals.

  20. Parasympathetic preganglionic cardiac motoneurons labeled after voluntary diving

    Directory of Open Access Journals (Sweden)

    W Michael ePanneton

    2014-01-01

    Full Text Available A dramatic bradycardia is induced by underwater submersion in vertebrates. The location of parasympathetic preganglionic cardiac motor neurons driving this aspect of the diving response was investigated using cFos immunohistochemistry combined with retrograde transport of cholera toxin subunit B (CTB to double-label neurons. After pericardial injections of CTB, trained rats voluntarily dove underwater, and their heart rates dropped immediately to 95±2bpm, an 80% reduction. After immunohistochemical processing, the vast majority of CTB labeled neurons were located in the reticular formation from the rostral cervical spinal cord to the facial motor nucleus, confirming previous studies. Labeled neurons caudal to the rostral ventrolateral medulla were usually spindle-shaped aligned along an oblique line running from the dorsal vagal nucleus to the ventrolateral reticular formation, while those more rostrally were multipolar with extended dendrites. Nine percent of retrogradely-labeled neurons were positive for both cFos and CTB after diving and 74% of these were found rostral to the obex. CTB also was transported transganglionically in primary afferent fibers, resulting in large granular deposits in dorsolateral, ventrolateral, and commissural subnuclei of the nucleus tractus solitarii and finer deposits in lamina I and IV-V of the trigeminocervical complex. The overlap of parasympathetic preganglionic cardiac motor neurons activated by diving with those activated by baro- and chemoreceptors in the rostral ventrolateral medulla is discussed. Thus the profound bradycardia seen with underwater submersion reinforces the notion that the mammalian diving response is the most powerful autonomic reflex known.

  1. Doppler bubble grades after diving and relevance of body fat.

    Science.gov (United States)

    Schellart, Nico A M; Vellinga, Tjeerd P van Rees; van Dijk, Frank J; Sterk, Wouter

    2012-10-01

    From the literature on venous gas embolism (VGE) and decompression sickness (DCS), it remains unclear whether body fat is a predisposing factor for VGE and DCS. Therefore, this study analyses body fat (range 16-44%) in relation to precordial VGE measured by Doppler bubble grades. Also examined is the effect of age (range 34-68 yr), body mass index (BMI; range 17-34 kg x m(-2)), and a model estimate of VO2(max) (maximal oxygen uptake; range 24-54 ml x kg(-1) x min(-1)). Bubble grades were determined in 43 recreational divers after an open sea air dive of 40 min to 20 m. Doppler bubble grade scores were transformed to the logarithm of the number of bubbles/cm2, logB, and the logarithm of the Kissman Integrated Severity Score (KISS) to allow numerical analysis. Statistical analyses were performed with Pearson's regular and partial correlations, and uni- and multivariate linear regressions. For divers in their midlife (and older), the analyses indicate that neither body fat nor BMI stimulate bubble formation, since correlations were nonsignificant. In contrast, age and especially VO2(max) appeared to determine VGE. For these types of dives it was found that logB = -1.1 + 0.02 age - 0.04Vo2(max). Based on these data we conclude that body fat and BMI seem less relevant for diving. We recommend that medical examinations pay more attention to VO2(max) and age, and that international dive institutions come to a consensus regarding VO2(max) criteria.

  2. Beaked Whale Group Deep Dive Behavior from Passive Acoustic Monitoring

    Science.gov (United States)

    2015-09-30

    1 DISTRIBUTION STATEMENT A. Approved for public release; distribution is unlimited. Beaked Whale Group Deep Dive Behavior from Passive...described explicitly, beaked whales are one of the cetacean taxa more sensitive to use of Navy sonar (Moretti et al., 2014; Tyack et al., 2011). Despite...their vulnerability, Blainville’s beaked whale , Mesoplodon densirostris (Md), are routinely detected year-round on the AUTEC range, coincident with

  3. Ultrasound lung "comets" increase after breath-hold diving.

    Science.gov (United States)

    Lambrechts, Kate; Germonpré, Peter; Charbel, Brian; Cialoni, Danilo; Musimu, Patrick; Sponsiello, Nicola; Marroni, Alessandro; Pastouret, Frédéric; Balestra, Costantino

    2011-04-01

    The purpose of the study was to analyze the ultrasound lung comets (ULCs) variation, which are a sign of extra-vascular lung water. Forty-two healthy individuals performed breath-hold diving in different conditions: dynamic surface apnea; deep variable-weight apnea and shallow, face immersed without effort (static maximal and non-maximal). The number of ULCs was evaluated by means of an ultrasound scan of the chest, before and after breath-hold diving sessions. The ULC score increased significantly from baseline after dynamic surface apnea (p = 0.0068), after deep breath-hold sessions (p = 0.0018), and after static maximal apnea (p = 0.031). There was no statistically significant difference between the average increase of ULC scores after dynamic surface apnea and deep breath-hold diving. We, therefore, postulate that extravascular lung water accumulation may be due to other factors than (deep) immersion alone, because it occurs during dynamic surface apnea as well. Three mechanisms may be responsible for this. First, the immersion-induced hydrostatic pressure gradient applied on the body causes a shift of peripheral venous blood towards the thorax. Second, the blood pooling effect found during the diving response Redistributes blood to the pulmonary vascular bed. Third, it is possible that the intense involuntary diaphragmatic contractions occurring during the "struggle phase" of the breath-hold can also produce a blood shift from the pulmonary capillaries to the pulmonary alveoli. A combination of these factors may explain the observed increase in ULC scores in deep, shallow maximal and shallow dynamic apneas, whereas shallow non-maximal apneas seem to be not "ULC provoking".

  4. Risk of Neurological Insult in Competitive Deep Breath-Hold Diving.

    Science.gov (United States)

    Tetzlaff, Kay; Schöppenthau, Holger; Schipke, Jochen D

    2017-02-01

    It has been widely believed that tissue nitrogen uptake from the lungs during breath-hold diving would be insufficient to cause decompression stress in humans. With competitive free diving, however, diving depths have been ever increasing over the past decades. A case is presented of a competitive free-diving athlete who suffered stroke-like symptoms after surfacing from his last dive of a series of 3 deep breath-hold dives. A literature and Web search was performed to screen for similar cases of subjects with serious neurological symptoms after deep breath-hold dives. A previously healthy 31-y-old athlete experienced right-sided motor weakness and difficulty speaking immediately after surfacing from a breathhold dive to a depth of 100 m. He had performed 2 preceding breath-hold dives to that depth with surface intervals of only 15 min. The presentation of symptoms and neuroimaging findings supported a clinical diagnosis of stroke. Three more cases of neurological insults were retrieved by literature and Web search; in all cases the athletes presented with stroke-like symptoms after single breath-hold dives of depths exceeding 100 m. Two of these cases only had a short delay to recompression treatment and completely recovered from the insult. This report highlights the possibility of neurological insult, eg, stroke, due to cerebral arterial gas embolism as a consequence of decompression stress after deep breath-hold dives. Thus, stroke as a clinical presentation of cerebral arterial gas embolism should be considered another risk of extreme breath-hold diving.

  5. High diving: evaluation of water impact and considerations on training methods

    OpenAIRE

    Napolitano, Salvatore; Di Tore, Pio Alfredo; Raiola, Gaetano

    2013-01-01

    High diving is a sport that became popular in recent years. Since 2013, FINA has added it to the official list of swimming disciplines. This pilot work focuses on two specific aspects of the High diving: 1. The impact with water: in high diving competitions the platforms are located at a height between 25 and 28 meters. The impact with the water exposes muscles, articulations and the whole athlete body to abnormal solicitations (Snyder & Snow, 1967). 2. The lack of opportunities for athletes ...

  6. Evaluating the Effects of Stressors on Immune Function during Simulated Dives in Marine Mammals

    Science.gov (United States)

    2015-04-24

    during Simulated Dives in Marine Mammals 5a. CONTRACT NUMBER 5b. GRANT NUMBER N00014-13-1-0768 5c. PROGRAM ELEMENT NUMBER 6. AUTHOR{S) Tracy...this study were to 1) gain understanding of marine mammal immunology and dive adaptation of the immune system by investigating the response of marine... mammal immune cells to simulated dives and 2) to evaluate the potential for additional stressors to alter the response of marine mammal immune cells to

  7. 46 CFR 197.434 - Surface-supplied mixed-gas diving.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 7 2010-10-01 2010-10-01 false Surface-supplied mixed-gas diving. 197.434 Section 197....434 Surface-supplied mixed-gas diving. The diving supervisor shall insure that— (a) When mixed-gas... supply meeting the requirements of § 197.340; and (k) The surface-supplied mixed-gas diver has the...

  8. A comparison of auditory brainstem responses across diving bird species

    Science.gov (United States)

    Crowell, Sara E.; Berlin, Alicia; Carr, Catherine E; Olsen, Glenn H.; Therrien, Ronald E; Yannuzzi, Sally E; Ketten, Darlene R

    2015-01-01

    There is little biological data available for diving birds because many live in hard-to-study, remote habitats. Only one species of diving bird, the black-footed penguin (Spheniscus demersus), has been studied in respect to auditory capabilities (Wever et al., Proc Natl Acad Sci USA 63:676–680, 1969). We, therefore, measured in-air auditory threshold in ten species of diving birds, using the auditory brainstem response (ABR). The average audiogram obtained for each species followed the U-shape typical of birds and many other animals. All species tested shared a common region of the greatest sensitivity, from 1000 to 3000 Hz, although audiograms differed significantly across species. Thresholds of all duck species tested were more similar to each other than to the two non-duck species tested. The red-throated loon (Gavia stellata) and northern gannet (Morus bassanus) exhibited the highest thresholds while the lowest thresholds belonged to the duck species, specifically the lesser scaup (Aythya affinis) and ruddy duck (Oxyura jamaicensis). Vocalization parameters were also measured for each species, and showed that with the exception of the common eider (Somateria mollisima), the peak frequency, i.e., frequency at the greatest intensity, of all species' vocalizations measured here fell between 1000 and 3000 Hz, matching the bandwidth of the most sensitive hearing range.

  9. Hemoptysis Due to Breath-Hold Diving Following Chemotherapy and Lung Irradiation

    OpenAIRE

    Gutsche, Markus; Kuschner, Ware G.

    2012-01-01

    Breath-hold diving, also known as free-diving, describes the practice of intentional immersion under water without an external supply of oxygen. Pulmonary hemorrhage with hemoptysis has been reported as a complication of immersion and breath-hold diving in young healthy athletes. We report the case of a 60-year-old man with a history of radiation and chemotherapy for breast carcinoma, who developed the abrupt onset of hemoptysis in the setting of swimming and breath-hold diving. A computed to...

  10. Epilepsy, scuba diving and risk assessment. Near misses and the need for ongoing vigilance.

    Science.gov (United States)

    Smart, David; Lippmann, John

    2013-03-01

    There is ongoing debate about the safety of scuba diving for individuals with a history of epilepsy. An in-water seizure is highly likely to be fatal. Recommendations for fitness to dive vary with some regarding epilepsy as an absolute contraindication to diving (South Pacific Underwater Medicine Society) and others permitting diving under strict criteria (United Kingdom Sport Diving Medical Committee) with diving to be postponed for a period of three to five years without seizures. Long-term follow up of people with epilepsy shows that at least one-third will have a recurrence and that the risk remains elevated for many years. We present three cases where individuals with a history of epilepsy (or likely epilepsy) almost fell through the cracks of health risk assessment, two with near-fatal consequences. These cases inform the on-going debate about fitness to dive for those with current or past epilepsy, and highlight the importance of education for doctors, dive professionals and divers about the risks associated with epilepsy and diving.

  11. [A CASE OF NATTOU (FERMENTED-SOYBEAN)-INDUCED LATE-ONSET ANAPHYLAXIS FOLLOWING SCUBA DIVING].

    Science.gov (United States)

    Nagakura, Toshikazu; Tanaka, Katsuichirou; Horikawa, Satoshi

    2015-06-01

    We here report a 34-years old male who had nattou-(fermented-soybean) induced late-onset anaphylaxis following SCUBA diving to about 20 m in the ocean off a small remote Japanese island (Kuroshima, Okinawa). He had eaten nattou for breakfast at 7:30 am. He traveled by boat to the dive site, dove twice and then ate lunch at 12:30 on the diving boat (no nattou at lunch). After lunch at 14:30 he dove again (third dive of the day) during which time itchiness started. Back on the diving boat, urticarial was noticed. At 15:30, while washing his diving gear at the diving shop near the harbor, he fainted. A physician arrived on the scene at 15:45. Chest sound was clear and SpO2 was 98%, and blood pressure was 60/- mmHg. Intra-venous hydrocortisone was given, however, his recovery was not satisfactory. Then he was transferred to the Yaeyama Hospital by helicopter at 17:45. The examination of diving computer analysis reveals no sign of increased residual nitrogen, denying the possibility of decompression syndrome. Prick to prick test shows a strongly positive response to nattou. Nattou-induced late-onset anaphylaxis following SCUBA diving was suspected.

  12. A methodology for identifying human error in U.S. Navy diving accidents.

    Science.gov (United States)

    O'Connor, Paul; O'Dea, Angela; Melton, John

    2007-04-01

    To better understand how human error contributes to U.S. Navy diving accidents. An analysis of 263 U.S. Navy diving accident and mishap reports revealed that the human factors classifications were not informative for further analysis, and 70% of mishaps were attributed to unknown causes; only 23% were attributed to human factors. Five diving fatality reports were examined using the consensual qualitative research (CQR) method to develop a taxonomy of six categories and 21 subcategories for classifying human errors in diving. In addition, 15 critical incident technique (CIT) interviews were conducted with U.S. Navy divers who had been involved in a diving accident or near miss and analyzed using the dive team error taxonomy. Overall, failures in situation awareness and leadership were the most common human errors made by the dive team. The dive team human error taxonomy could aid in accident investigation and in the training and evaluation of U.S. Navy divers. The development of the dive team human error taxonomy has generated a number of considerations that researchers should take into account when developing, or adapting, an error taxonomy from one industry to another.

  13. Argon used as dry suit insulation gas for cold-water diving

    OpenAIRE

    Vrijdag, Xavier CE; van Ooij, Pieter-Jan AM; van Hulst, Robert A

    2013-01-01

    Background Cold-water diving requires good thermal insulation because hypothermia is a serious risk. Water conducts heat more efficiently compared to air. To stay warm during a dive, the choice of thermal protection should be based on physical activity, the temperature of the water, and the duration of exposure. A dry suit, a diving suit filled with gas, is the most common diving suit in cold water. Air is the traditional dry suit inflation gas, whereas the thermal conductivity of argon is ap...

  14. Optimization of accelerated learning technique sport diving students of higher educational institutions

    National Research Council Canada - National Science Library

    Natalya Balamutova; Svetlana Shyryaeva

    2015-01-01

    Purpose: optimizing the learning process engineering sport diving students of higher educational institutions on the basis of experimental detection features changes leading factors in teaching swimming...

  15. Constraint lines and performance envelopes in behavioral physiology: the case of the aerobic dive limit.

    Directory of Open Access Journals (Sweden)

    Markus eHorning

    2012-09-01

    Full Text Available Constraint lines - the boundaries that delimit point clouds in bivariate scattergrams - have been applied in macro-ecology to quantify the effects of limiting factors on response variables, but have not been applied to the behavioral performance and physiological ecology of individual vertebrates. I propose that behavioral scattergrams of air-breathing, diving vertebrates contain informative edges that convey insights into physiological constraints that shape the performance envelopes of divers. In the classic example of repeated cycles of apnea and eupnea in diving, airbreathing vertebrates, the need to balance oxygen consumption and intake should differentially constrain recovery for dives within or exceeding the aerobic dive limit. However, the bulk of variance observed in recovery versus dive duration scattergrams originates from undetermined behavioral variables, and deviations from overall stasis may become increasingly apparent at progressively smaller scales of observation. As shown on dive records from 79 Galápagos fur seals, the selection of appropriate time scales of integration yields two distinct recovery boundaries for dive series within and beyond the estimated aerobic dive limit. An analysis of the corresponding constraint lines is independent of central tendencies in data and avoids violating parametric assumptions for large data sets where variables of interest account for only a small portion of observed variance. I hypothesize that the intercept between these constraint lines represents the effective aerobic dive limit, and present physiological and ecological considerations to support this hypothesis.

  16. Functional properties of myoglobins from five whale species with different diving capacities.

    Science.gov (United States)

    Helbo, Signe; Fago, Angela

    2012-10-01

    Whales show an exceptionally wide range of diving capabilities and many express high amounts of the O(2) carrier protein myoglobin (Mb) in their muscle tissues, which increases their aerobic diving capacity. Although previous studies have mainly focused on the muscle Mb concentration and O(2) carrying capacity as markers of diving behavior in whales, it still remains unexplored whether whale Mbs differ in their O(2) affinities and nitrite reductase and peroxidase enzymatic activities, all functions that could contribute to differences in diving capacities. In this study, we have measured the functional properties of purified Mbs from five toothed whales and two baleen whales and have examined their correlation with average dive duration. Results showed that some variation in functional properties exists among whale Mbs, with toothed whale Mbs having higher O(2) affinities and nitrite reductase activities (similar to those of horse Mb) compared with baleen whale Mbs. However, these differences did not correlate with average dive duration. Instead, a significant correlation was found between whale Mb concentration and average duration and depth of dives, and between O(2) affinity and nitrite reductase activity when including horse Mb. Despite the fact that the functional properties showed little species-specific differences in vitro, they may still contribute to enhancing diving capacity as a result of the increased muscle Mb concentration found in extreme divers. In conclusion, Mb concentration rather than specific functional reactivities may support whale diving performance.

  17. Deep-diving by narwhals Monodon monoceros: differences in foraging behavior between wintering areas?

    DEFF Research Database (Denmark)

    Laidre, K. L.; Heide-Jørgensen, M. P.; Dietz, R.

    2003-01-01

    -depth recorders (SLTDRs) were used to examine differences in narwhal Monodon monoceros diving behavior and habitat selection among 3 sub-populations in Canada and West Greenland (n = 16 individuals). The number of dives to different depths and time allocation within the water column was investigated in 3 seasons...... between summer and winter. Clear differences were observed between 2 wintering grounds. Whales occupying one wintering ground spent most of their time diving to between 200 and 400 m (25 dives per day, SE 3), confirmed by both depth and temperature recording tags. In contrast, narwhals in a separate...

  18. AFSC/ABL: Delta Submersible Dive Video Archive in Alaska, 1988-2009

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Seafloor habitat and fish data collected from videos obtained from Delta submarine dives conducted by Auke Bay Laboratories.

  19. Detection of venous gas emboli after repetitive breath-hold dives: case report

    OpenAIRE

    Cialoni, D; Pieri, M; Giunchi, G.; Sponsiello, N; Lanzone, MA; Torcello, L; Boaretto, G; Marroni, A.

    2016-01-01

    Introduction: Neurological symptoms after breath-hold (BH) diving are often referred to as “Taravana” and considered a form of decompression sickness. However, the presence of “high” gas embolism after BH diving has never been clearly shown. This study showed high bubble formation after BH diving. Materials and methods: We performed transthoracic echocardiography on a 53-year-old male spearfishing diver (180 cm; 80 kg; BMI 24.7) 15 minutes before diving and at 15-minute intervals for 90 m...

  20. Changes in dive behaviour during naval sonar exposure in killer whales, long-finned pilot whales and sperm whales

    Directory of Open Access Journals (Sweden)

    Lise Doksæter Sivle

    2012-10-01

    Full Text Available Anthropogenic underwater sound in the environment might potentially affect the behavior of marine mammals enough to have an impact on their reproduction and survival. Diving behavior of 5 killer whales (Orcinus orca, 7 long-finned pilot whales (Globicephala melas and 4 sperm whales (Physeter macrocephalus were studied during controlled exposures to naval sonar (LFAS: 1-2 kHz and MFAS: 6-7 kHz during three field seasons (2006-2009. Diving behavior was monitored before, during and after sonar exposure using an archival tag placed on the animal with suction cups. The tag recorded the animal’s vertical movement, and additional data on horizontal movement and vocalizations were used to determine behavioral modes. Killer whales that were conducting deep dives at sonar onset changed abruptly to shallow diving during LFAS, while killer whales conducting deep dives at the onset of MFAS did not alter dive mode. When in shallow diving mode at sonar onset, killer whales did not change their diving behavior. Pilot and sperm whales performed normal deep dives during MFAS exposure. During LFAS exposures, long-finned pilot whales mostly performed fewer deep dives and some sperm whales performed shallower and shorter dives. Acoustic recording data presented previously indicates that deep diving is associated with feeding. Therefore, the observed changes in dive behavior of the three species could potentially reduce the foraging efficiency of the affected animals.

  1. Brain damage in commercial breath-hold divers.

    Directory of Open Access Journals (Sweden)

    Kiyotaka Kohshi

    Full Text Available Acute decompression illness (DCI involving the brain (Cerebral DCI is one of the most serious forms of diving-related injuries which may leave residual brain damage. Cerebral DCI occurs in compressed air and in breath-hold divers, likewise. We conducted this study to investigate whether long-term breath-hold divers who may be exposed to repeated symptomatic and asymptomatic brain injuries, show brain damage on magnetic resonance imaging (MRI.Our study subjects were 12 commercial breath-hold divers (Ama with long histories of diving work in a district of Japan. We obtained information on their diving practices and the presence or absence of medical problems, especially DCI events. All participants were examined with MRI to determine the prevalence of brain lesions.Out of 12 Ama divers (mean age: 54.9±5.1 years, four had histories of cerebral DCI events, and 11 divers demonstrated ischemic lesions of the brain on MRI studies. The lesions were situated in the cortical and/or subcortical area (9 cases, white matters (4 cases, the basal ganglia (4 cases, and the thalamus (1 case. Subdural fluid collections were seen in 2 cases.These results suggest that commercial breath-hold divers are at a risk of clinical or subclinical brain injury which may affect the long-term neuropsychological health of divers.

  2. Does recreational scuba diving have clinically significant effect on routine haematological parameters?

    Science.gov (United States)

    Perovic, Antonija; Nikolac, Nora; Braticevic, Marina Njire; Milcic, Ana; Sobocanec, Sandra; Balog, Tihomir; Dabelic, Sanja; Dumic, Jerka

    2017-06-15

    Scuba diving represents a combination of exercise and changes in environmental conditions. This study aimed to evaluate changes in haematological parameters after recreational scuba diving in order to identify clinically significant changes. The study included males, 17 recreational divers, median age (range) 41 (30-52) years. Blood samples were taken before diving, immediately after diving to 30 meters for 30 minutes, 3 hours and 6 hours after diving. Complete blood counts were analyzed on the Cell Dyn Ruby haematology analyzer. Statistical significance between successive measurements was tested using Friedman test. The difference between the two measurements was judged against desirable bias (DSB) derived from biological variation and calculated reference change values (RCV). The difference higher than RCV was considered clinically significant. A statistically significant increase and difference judging against DSB was observed: for neutrophils immediately, 3 and 6 hours after diving (18%, 34% and 36%, respectively), for white blood cells (WBCs) 3 and 6 hours after diving (20% and 25%, respectively), for lymphocytes (20%) and monocytes (23%) 6 hours after diving. A statistically significant decrease and difference judging against DSB was found: immediately after diving for monocytes (- 15%), 3 and 6 hours after diving for red blood cells (RBCs) (- 2.6% and -2.9%, respectively), haemoglobin (- 2.1% and - 2.8%, respectively) and haematocrit (- 2.4% and - 3.2%, respectively). A clinically significant change was not found for any of the test parameters when compared to RCV. Observed statistically significant changes after recreational scuba diving; WBCs, neutrophils, lymphocytes, monocytes increase and RBCs, haemoglobin, haematocrit decrease, probably will not affect clinical decision.

  3. How man-made interference might cause gas bubble emboli in deep diving whales

    Directory of Open Access Journals (Sweden)

    Andreas eFahlman

    2014-01-01

    Full Text Available Recent cetacean mass strandings in close temporal and spatial association with sonar activity has raised the concern that anthropogenic sound may harm breath-hold diving marine mammals. Necropsy results of the stranded whales have shown evidence of bubbles in the tissues, similar to those in human divers suffering from decompression sickness (DCS. It has been proposed that changes in behavior or physiological responses during diving could increase tissue and blood N2 levels, thereby increasing DCS risk. Dive data recorded from sperm, killer, long-finned pilot, Blainville’s beaked and Cuvier’s beaked whales before and during exposure to low- (1-2 kHz and mid- (2-7 kHz frequency active sonar were used to estimate the changes in blood and tissue N2 tension (PN2. Our objectives were to determine if differences in 1 dive behavior or 2 physiological responses to sonar are plausible risk factors for bubble formation. The theoretical estimates indicate that all species may experience high N2 levels. However, unexpectedly, deep diving generally result in higher end-dive PN2 as compared with shallow diving. In this focused review we focus on three possible explanations: 1 We revisit an old hypothesis that CO2, because of its much higher diffusivity, form bubble precursors that continue to grow in N2 supersaturated tissues. Such a mechanism would be less dependent on the alveolar collapse depth but affected by elevated levels of CO2 following a burst of activity during sonar exposure. 2 During deep dives, a greater duration of time might be spent at depths where gas exchange continues as compared with shallow dives. The resulting elevated levels of N2 in deep diving whales might also make them more susceptible to anthropogenic disturbances. 3 Extended duration of dives even at depths beyond where the alveoli collapse could result in slow continuous accumulation of N2 in the adipose tissues that eventually becomes a liability.

  4. How man-made interference might cause gas bubble emboli in deep diving whales.

    Science.gov (United States)

    Fahlman, Andreas; Tyack, Peter L; Miller, Patrick J O; Kvadsheim, Petter H

    2014-01-01

    Recent cetacean mass strandings in close temporal and spatial association with sonar activity has raised the concern that anthropogenic sound may harm breath-hold diving marine mammals. Necropsy results of the stranded whales have shown evidence of bubbles in the tissues, similar to those in human divers suffering from decompression sickness (DCS). It has been proposed that changes in behavior or physiological responses during diving could increase tissue and blood N2 levels, thereby increasing DCS risk. Dive data recorded from sperm, killer, long-finned pilot, Blainville's beaked and Cuvier's beaked whales before and during exposure to low- (1-2 kHz) and mid- (2-7 kHz) frequency active sonar were used to estimate the changes in blood and tissue N2 tension (PN2 ). Our objectives were to determine if differences in (1) dive behavior or (2) physiological responses to sonar are plausible risk factors for bubble formation. The theoretical estimates indicate that all species may experience high N2 levels. However, unexpectedly, deep diving generally result in higher end-dive PN2 as compared with shallow diving. In this focused review we focus on three possible explanations: (1) We revisit an old hypothesis that CO2, because of its much higher diffusivity, forms bubble precursors that continue to grow in N2 supersaturated tissues. Such a mechanism would be less dependent on the alveolar collapse depth but affected by elevated levels of CO2 following a burst of activity during sonar exposure. (2) During deep dives, a greater duration of time might be spent at depths where gas exchange continues as compared with shallow dives. The resulting elevated levels of N2 in deep diving whales might also make them more susceptible to anthropogenic disturbances. (3) Extended duration of dives even at depths beyond where the alveoli collapse could result in slow continuous accumulation of N2 in the adipose tissues that eventually becomes a liability.

  5. Diving of great shearwaters (Puffinus gravis in cold and warm water regions of the South Atlantic Ocean.

    Directory of Open Access Journals (Sweden)

    Robert A Ronconi

    Full Text Available BACKGROUND: Among the most widespread seabirds in the world, shearwaters of the genus Puffinus are also some of the deepest diving members of the Procellariiformes. Maximum diving depths are known for several Puffinus species, but dive depths or diving behaviour have never been recorded for great shearwaters (P. gravis, the largest member of this genus. This study reports the first high sampling rate (2 s of depth and diving behaviour for Puffinus shearwaters. METHODOLOGY/PRINCIPAL FINDINGS: Time-depth recorders (TDRs were deployed on two female great shearwaters nesting on Inaccessible Island in the South Atlantic Ocean, recording 10 consecutive days of diving activity. Remote sensing imagery and movement patterns of 8 males tracked by satellite telemetry over the same period were used to identify probable foraging areas used by TDR-equipped females. The deepest and longest dive was to 18.9 m and lasted 40 s, but most (>50% dives were <2 m deep. Diving was most frequent near dawn and dusk, with <0.5% of dives occurring at night. The two individuals foraged in contrasting oceanographic conditions, one in cold (8 to 10°C water of the Sub-Antarctic Front, likely 1000 km south of the breeding colony, and the other in warmer (10 to 16°C water of the Sub-tropical Frontal Zone, at the same latitude as the colony, possibly on the Patagonian Shelf, 4000 km away. The cold water bird spent fewer days commuting, conducted four times as many dives as the warm water bird, dived deeper on average, and had a greater proportion of bottom time during dives. CONCLUSIONS/SIGNIFICANCE: General patterns of diving activity were consistent with those of other shearwaters foraging in cold and warm water habitats. Great shearwaters are likely adapted to forage in a wide range of oceanographic conditions, foraging mostly with shallow dives but capable of deep diving.

  6. CERN Computing in Commercial Clouds

    Science.gov (United States)

    Cordeiro, C.; Field, L.; Garrido Bear, B.; Giordano, D.; Jones, B.; Keeble, O.; Manzi, A.; Martelli, E.; McCance, G.; Moreno-García, D.; Traylen, S.

    2017-10-01

    By the end of 2016 more than 10 Million core-hours of computing resources have been delivered by several commercial cloud providers to the four LHC experiments to run their production workloads, from simulation to full chain processing. In this paper we describe the experience gained at CERN in procuring and exploiting commercial cloud resources for the computing needs of the LHC experiments. The mechanisms used for provisioning, monitoring, accounting, alarming and benchmarking will be discussed, as well as the involvement of the LHC collaborations in terms of managing the workflows of the experiments within a multicloud environment.

  7. 9 CFR 146.6 - Specific provisions for participating slaughter plants.

    Science.gov (United States)

    2010-01-01

    ... slaughter plants. 146.6 Section 146.6 Animals and Animal Products ANIMAL AND PLANT HEALTH INSPECTION SERVICE... General Provisions § 146.6 Specific provisions for participating slaughter plants. (a) Only commercial upland game bird, commercial waterfowl, meat-type chicken, and meat-type turkey slaughter plants that are...

  8. Body cooling and its energetic implications for feeding and diving of tufted ducks

    NARCIS (Netherlands)

    de Leeuw, JJ; Butler, PJ; Woakes, AJ; Zegwaard, F

    1998-01-01

    Wintering in a temperate climate with low water temperatures is energetically expensive for diving ducks. The energy costs associated with body cooling due to diving and ingesting large amounts of cold food were measured in tufted ducks (Aythya fuligula) feeding on zebra mussels (Dreissena

  9. Scientific Diving Training Course. Red Sea & Gulf of Aden Programme (PERSGA).

    Science.gov (United States)

    Arab Organization for Education and Science, Cairo (Egypt).

    This document presents the scientific diving training course organized by the Arab League Educational, Cultural and Scientific Organization (ALECSO) for the Program for Environmental Studies, Red Sea and Gulf of Aden (PERSGA). This course of six weeks duration aims to produce a person who is capable of carrying out scientific diving tasks in the…

  10. Shear force imaging of soft samples in liquid using a diving bell concept

    NARCIS (Netherlands)

    Koopman, M.; de Bakker, B.I.; Garcia Parajo, M.F.; van Hulst, N.F.

    2003-01-01

    We present a reliable and easy-to-use system, with a perfect analogy to a diving bell, to perform tuning fork based shear force microscopy o­n soft cells in liquid. Using the diving bell concept the tuning fork vibrates in air, while the tip is immersed in solution. In this way Q factors of 200 and

  11. Effects of diving and oxygen on autonomic nervous system and cerebral blood flow.

    Science.gov (United States)

    Winklewski, Pawel J; Kot, Jacek; Frydrychowski, Andrzej F; Nuckowska, Magdalena K; Tkachenko, Yurii

    2013-09-01

    Recreational scuba diving is a popular leisure activity with the number of divers reaching several millions worldwide. Scuba diving represents a huge challenge for integrative physiology. In mammalian evolution, physiological reflexes developed to deal with lack of oxygen, rather than with an excess, which makes adaptations to scuba diving more difficult to describe and understand than those associated with breath-hold diving. The underwater environment significantly limits the use of equipment to register the organism's functions, so, in most instances, scientific theories are built on experiments that model real diving to some extent, like hyperbaric exposures, dive reflexes or water immersion. The aim of this review is to summarise the current knowledge related to the influence exerted by physiological conditions specific to diving on the autonomic nervous system and cerebral blood flow. The main factors regulating cerebral blood flow during scuba diving are discussed as follows: 1) increased oxygen partial pressure; 2) immersion-related trigemino-cardiac reflexes and 3) exposure to cold, exercise and stress. Also discussed are the potential mechanisms associated with immersion pulmonary oedema.

  12. Biosonar, dive, and foraging activity of satellite tracked harbor porpoises (Phocoena phocoena)

    DEFF Research Database (Denmark)

    Linnenschmidt, Meike; Teilmann, Jonas; Akamatsu, Tomonari

    2013-01-01

    rates and higher dive activity at night. A female traveling in open waters showed no diel rhythm, but its sonar activity was three times higher compared to the males’. Considerable individual differences in dive and echolocation activity could have been influenced by biological and physical factors...

  13. Bubble formation after a 20-m dive: deep-stop vs. shallow-stop decompression profiles

    NARCIS (Netherlands)

    Schellart, Nico A. M.; Corstius, Jan-Jaap Brandt; Germonpré, Peter; Sterk, Wouter

    2008-01-01

    OBJECTIVES: It is claimed that performing a "deep stop," a stop at about half of maximal diving depth (MDD), can reduce the amount of detectable precordial bubbles after the dive and may thus diminish the risk of decompression sickness. In order to ascertain whether this reduction is caused by the

  14. Heart rate regulation in diving sea lions: the vagus nerve rules.

    Science.gov (United States)

    Ponganis, Paul J; McDonald, Birgitte I; Tift, Michael S; Williams, Cassondra L

    2017-04-15

    Recent publications have emphasized the potential generation of morbid cardiac arrhythmias secondary to autonomic conflict in diving marine mammals. Such conflict, as typified by cardiovascular responses to cold water immersion in humans, has been proposed to result from exercise-related activation of cardiac sympathetic fibers to increase heart rate, combined with depth-related changes in parasympathetic tone to decrease heart rate. After reviewing the marine mammal literature and evaluating heart rate profiles of diving California sea lions (Zalophus californianus), we present an alternative interpretation of heart rate regulation that de-emphasizes the concept of autonomic conflict and the risk of morbid arrhythmias in marine mammals. We hypothesize that: (1) both the sympathetic cardiac accelerator fibers and the peripheral sympathetic vasomotor fibers are activated during dives even without exercise, and their activities are elevated at the lowest heart rates in a dive when vasoconstriction is maximal, (2) in diving animals, parasympathetic cardiac tone via the vagus nerve dominates over sympathetic cardiac tone during all phases of the dive, thus producing the bradycardia, (3) adjustment in vagal activity, which may be affected by many inputs, including exercise, is the primary regulator of heart rate and heart rate fluctuations during diving, and (4) heart beat fluctuations (benign arrhythmias) are common in marine mammals. Consistent with the literature and with these hypotheses, we believe that the generation of morbid arrhythmias because of exercise or stress during dives is unlikely in marine mammals. © 2017. Published by The Company of Biologists Ltd.

  15. The potential for dive tourism led entrepreneurial marine protected areas in Curacao

    NARCIS (Netherlands)

    Groot, de J.; Bush, S.R.

    2010-01-01

    Despite the successful establishment of marine protected areas in the Netherlands Antilles, such as Saba and Bonaire, government-led protection of the reefs surrounding Curacao has repeatedly failed. In the absence of effective state regulation, dive operations have taken de facto control over dive

  16. Using Stimulation of the Diving Reflex in Humans to Teach Integrative Physiology

    Science.gov (United States)

    Choate, Julia K.; Denton, Kate M.; Evans, Roger G.; Hodgson, Yvonne

    2014-01-01

    During underwater submersion, the body responds by conserving O[subscript 2] and prioritizing blood flow to the brain and heart. These physiological adjustments, which involve the nervous, cardiovascular, and respiratory systems, are known as the diving response and provide an ideal example of integrative physiology. The diving reflex can be…

  17. Argon used as dry suit insulation gas for cold-water diving

    NARCIS (Netherlands)

    Vrijdag, Xavier C. E.; van Ooij, Pieter-Jan A. M.; van Hulst, Robert A.

    2013-01-01

    Cold-water diving requires good thermal insulation because hypothermia is a serious risk. Water conducts heat more efficiently compared to air. To stay warm during a dive, the choice of thermal protection should be based on physical activity, the temperature of the water, and the duration of

  18. The diving mouthpiece and the conditions of the temporomandibular joints. Preliminary study

    Directory of Open Access Journals (Sweden)

    Walczyńska – Dragon Karolina

    2016-06-01

    Full Text Available The article presents the results of research on the effects of a long-term exposure to non-physiological location of anatomical elements of the masticatory organ in the course of diving. The said exposure is connected with the utilisation of various types of diving mouthpieces.

  19. Role of cardiorespiratory abnormalities, smoking and dive characteristics in the manifestations of neurological decompression illness.

    Science.gov (United States)

    Wilmshurst, P; Davidson, C; O'Connell, G; Byrne, C

    1994-03-01

    1. Blind analysis of contrast echocardiograms to detect intracardiac shunts, blind analysis of lung function tests for evidence of small airways disease, smoking history and dive characteristics were examined in an attempt to explain neurological symptoms that occurred within 5 min of surfacing from unprovocative dives. 2. Pulmonary abnormalities were significantly more frequent in those divers without intracardiac shunts (50%) than in those with shunts (0%). Smoking was more common in those divers without shunts (55% versus 15%), although this just failed to reach conventional significance levels. Divers without shunts experienced cerebral rather than spinal symptoms after significantly shallower dives with lower tissue nitrogen loads. Depths of dives, tissue nitrogen loads and clinical manifestations in those divers without shunts were similar to the findings in divers who had symptoms after rapid ascents. Despite conservative dive profiles, clinical manifestations in divers with shunts resembled those observed after missed decompression stops. 3. The findings suggest that occult lung disease, and probably smoking, increase the risk of neurological symptoms, even after unprovocative dives, and the similarity of the dive profiles and clinical manifestations to cases with rapid ascents suggest that pulmonary barotrauma and arterial gas embolism are responsible. In divers with intracardiac shunts the different dive profiles and clinical manifestations imply that there is another mechanism, involving different tissue and bubble nitrogen kinetics resulting in venous gas liberation and peripheral amplification in embolized tissues, rather than paradoxical embolism per se.

  20. Constructing safety through “contrast” during training in scuba diving ...

    African Journals Online (AJOL)

    Safety is a very important aspect in scuba diving, as not complying with safety regulations can lead to serious injury or even death. In this article the researchers focused on the discursive construction of safety during training in scuba diving. The research position fell within the field of discursive psychology. The researcher ...

  1. Competitive Swimming and Diving. Official Rules, Officating. August 1983-August 1984. NAGWS Guide.

    Science.gov (United States)

    American Alliance for Health, Physical Education, Recreation and Dance, Reston, VA. National Association for Girls and Women in Sport.

    Arranged in three sections, this pamphlet details the rules, officiating techniques, and official records for girls' and womens' competitive swimming and diving. Section 1 lists members of the national rules committee, major rule changes for 1983-84, and official rules for swimming and diving competition. Section 2 contains officiating tips,…

  2. Changes in dive behavior during naval sonar exposure in killer whales, long-finned pilot whales, and sperm whales

    Science.gov (United States)

    Sivle, L. D.; Kvadsheim, P. H.; Fahlman, A.; Lam, F. P. A.; Tyack, P. L.; Miller, P. J. O.

    2012-01-01

    Anthropogenic underwater sound in the environment might potentially affect the behavior of marine mammals enough to have an impact on their reproduction and survival. Diving behavior of four killer whales (Orcinus orca), seven long-finned pilot whales (Globicephala melas), and four sperm whales (Physeter macrocephalus) was studied during controlled exposures to naval sonar [low frequency active sonar (LFAS): 1–2 kHz and mid frequency active sonar (MFAS): 6–7 kHz] during three field seasons (2006–2009). Diving behavior was monitored before, during and after sonar exposure using an archival tag placed on the animal with suction cups. The tag recorded the animal's vertical movement, and additional data on horizontal movement and vocalizations were used to determine behavioral modes. Killer whales that were conducting deep dives at sonar onset changed abruptly to shallow diving (ShD) during LFAS, while killer whales conducting deep dives at the onset of MFAS did not alter dive mode. When in ShD mode at sonar onset, killer whales did not change their diving behavior. Pilot and sperm whales performed normal deep dives (NDD) during MFAS exposure. During LFAS exposures, long-finned pilot whales mostly performed fewer deep dives and some sperm whales performed shallower and shorter dives. Acoustic recording data presented previously indicates that deep diving (DD) is associated with feeding. Therefore, the observed changes in dive behavior of the three species could potentially reduce the foraging efficiency of the affected animals. PMID:23087648

  3. Changes in dive behavior during naval sonar exposure in killer whales, long-finned pilot whales, and sperm whales.

    Science.gov (United States)

    Sivle, L D; Kvadsheim, P H; Fahlman, A; Lam, F P A; Tyack, P L; Miller, P J O

    2012-01-01

    Anthropogenic underwater sound in the environment might potentially affect the behavior of marine mammals enough to have an impact on their reproduction and survival. Diving behavior of four killer whales (Orcinus orca), seven long-finned pilot whales (Globicephala melas), and four sperm whales (Physeter macrocephalus) was studied during controlled exposures to naval sonar [low frequency active sonar (LFAS): 1-2 kHz and mid frequency active sonar (MFAS): 6-7 kHz] during three field seasons (2006-2009). Diving behavior was monitored before, during and after sonar exposure using an archival tag placed on the animal with suction cups. The tag recorded the animal's vertical movement, and additional data on horizontal movement and vocalizations were used to determine behavioral modes. Killer whales that were conducting deep dives at sonar onset changed abruptly to shallow diving (ShD) during LFAS, while killer whales conducting deep dives at the onset of MFAS did not alter dive mode. When in ShD mode at sonar onset, killer whales did not change their diving behavior. Pilot and sperm whales performed normal deep dives (NDD) during MFAS exposure. During LFAS exposures, long-finned pilot whales mostly performed fewer deep dives and some sperm whales performed shallower and shorter dives. Acoustic recording data presented previously indicates that deep diving (DD) is associated with feeding. Therefore, the observed changes in dive behavior of the three species could potentially reduce the foraging efficiency of the affected animals.

  4. Sebastian Pinnacles, Oculina Banks Clelia Dive 619 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  5. Jeff's Reef, Oculina Banks Clelia Dive 606 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These are data from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  6. Sebastian Pinnacles, Oculina Banks Clelia Dive 615 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  7. Eau Gallie, Oculina Banks Clelia Dive 609 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  8. Sebastian Pinnacles, Oculina Banks Clelia Dive 614 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  9. Chapman's Reef, Oculina Banks Clelia Dive 620 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  10. Cocoa Beach, Oculina Banks Clelia Dive 617 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of from fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance...

  11. Cape Canaveral, Oculina Banks Clelia Dive 616 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These are data from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  12. Eau Gallie, Oculina Banks Clelia Dive 608 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  13. Sebastian Pinnacles, Oculina Banks Clelia Dive 618 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  14. Chapman's Reef, Oculina Banks Clelia Dive 621 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These data are from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  15. Jeff's Reef Oculina Banks Clelia Dive 607 Narrative 2001 - Videotape and Visual Observations from Submersible Dives to the Oculina Banks Deep Sea Coral Reefs (NODC Accession 0047190)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — These are data from one of fourteen 2001 submersible "Clelia" dives. Narratives including habitat descriptions and estimates of megafaunal species abundance were...

  16. PNW cetacean muscle biochemistry - Muscle Myoglobin Content and Acid Buffering Capacity of Cetaceans from the Pacific Northwest to Assess Dive Capacity and the Development of Diving Capabilities

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This project assesses the development of two important skeletal muscle adaptations for diving (enhanced myoglobin content and acid buffering capacities) in a range...

  17. Chain of events analysis for a scuba diving fatality.

    Science.gov (United States)

    Lippmann, John; Stevenson, Christopher; McD Taylor, David; Williams, Jo; Mohebbi, Mohammadreza

    2017-09-01

    A scuba diving fatality usually involves a series of related events culminating in death. Several studies have utilised a chain of events-type analysis (CEA) to isolate and better understand the accident sequence in order to facilitate the creation of relevant countermeasures. The aim of this research was to further develop and better define a process for performing a CEA to reduce potential subjectivity and increase consistency between analysts. To develop more comprehensive and better-defined criteria, existing criteria were modified and a template was created and tested using a CEA. Modifications comprised addition of a category for pre-disposing factors, expansion of criteria for the triggers and disabling agents present during the incident, and more specific inclusion criteria to better encompass a dataset of 56 fatalities. Four investigators (raters) used both the previous criteria and this template, in randomly assigned order, to examine a sample of 13 scuba diver deaths. Individual results were scored against the group consensus for the CEA. Raters' agreement consistency was compared using the Index of Concordance and intra-class correlation coefficients (ICC). The template is presented. The index of concordance between the raters increased from 62% (194⁄312) using the previous criteria to 82% (257⁄312) with use of this template indicating a substantially higher inter-rater agreement when allocating criteria. The agreement in scoring with and without template use was also quantified by ICC which were generally graded as low, illustrating a substantial change in consistency of scoring before and after template use. The template for a CEA for a scuba diving fatality improves consistency of interpretation between users and may improve comparability of diving fatality reports.

  18. Experiment of nitrox saturation diving with trimix excursion.

    Science.gov (United States)

    Shi, Z Y

    1998-11-01

    Depth limitations to diving operation with air as the breathing gas are well known: air density, oxygen toxicity, nitrogen narcosis and requirement for decompression. The main objectives of our experiment were to assess the decompression, counterdiffusion and performance aspect of helium-nitrogen-oxygen excursions from nitrox saturation. The experiment was carried out in a wet diving stimulator with "igloo" attached to a 2-lock living chamber. Four subjects of two teams of 2 divers were saturated at 25 msw simulated depth in a nitrogen oxygen chamber environment for 8 days, during which period they performed 32 divers-excursions to 60 or 80 msw pressure. Excursion gas mix was trimix of 14.6% oxygen, 50% helium and 35.4% nitrogen, which gave a bottom oxygen partial pressure of 1.0 bars at 60 msw and 1.3 at 80 msw. Excursions were for 70 min at 60 msw with three 10-min work periods and 40 min at 80 msw with two 10-min work periods. Work was on a bicycle ergometer at a moderate level. We calculated the excursion decompression with M-Values based on methods of Hamilton (Hamilton et al., 1990). Staged decompression took 70 min for the 60 msw excursion and 98 min for 80 msw, with stops beginning at 34 or 43 msw respectively. After the second dive day bubbles were heard mainly in one diver but in three divers overall, to Spencer Grade III some times. No symptoms were reported. Saturation decompression using the Repex procedures began at 40 msw and was uneventful: Grade II and sometimes III bubbles persisted in 2 of the four divers until 24 hr after surfacing. We conclude that excursions with mixture rich in helium can be performed effectively to as deep as 80 msw using these procedures.

  19. On the adiabatic theorem when eigenvalues dive into the continuum

    DEFF Research Database (Denmark)

    Cornean, Decebal Horia; Jensen, Arne; Knörr, Hans Konrad

    For a Wigner-Weisskopf model of an atom consisting of a quantum dot coupled to an energy reservoir described by a three-dimensional Laplacian we study the survival probability of a bound state when the dot energy varies smoothly and adiabatically in time. The initial state corresponds to a discre...... eigenvalue which dives into the continuous spectrum and re-emerges from it as the dot energy is varied in time and finally returns to its initial value. Our main result is that for a large class of couplings, the survival probability of this bound state vanishes in the adiabatic limit....

  20. Suitability Analysis For Scuba Diving To Develop Marine Tourism At Saebus Island, East Java, Indonesia

    Science.gov (United States)

    Wijaya, Putranto; Putra, Tri; Hidayat, Fatra; Levraeni, Chandra; Rizmaadi, Mada; Ambariyanto, Ambariyanto

    2018-02-01

    Indonesian government currently has policies to improve the performance of the tourism sector, including marine tourism. One of the attractions of marine tourism is the coral ecosystem especially through scuba diving activities. The purpose of this study was to determine the suitability of the coral ecosystem on Saebus Island, East Java, to find appropriate locations for scuba diving activities. Purposive samplings were done around the island to determine four stations which will be assessed through suitability analysis. Tourism Suitability Index was used to assess all stations for scuba diving activities. The result showed that all four stations were categorized as very suitable with the score: 85%, 85%, 85% and 83%, respectively. Several aspects that need to be improved and anticipated for diving at all stations are coral coverage and water current. These results suggest that there are several spots around Saebus Island that are suitable for diving site, and can be promoted as marine tourism destination.

  1. Decompression from He-N2-O2 (TRIMIX) Bounce Dives Is Not More Efficient Than From He-O2 (HELIOX) Bounce Dives

    Science.gov (United States)

    2015-05-28

    SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT 18. NUMBER OF PAGES 19a. NAME OF RESPONSIBLE PERSON NEDU Librarian a. REPORT...abnormality. The Treatment Table 6 was completed without extensions and without incident, and the diver was observed for an abbreviated post-dive period...no extensions . DIVER ID 35, 17JUNE 2014 Background: A 44 year old male active duty who completed the Trimix Experimental Dive protocol at 12:58

  2. 77 FR 75400 - Labeling Requirements for Commercial and Industrial Equipment

    Science.gov (United States)

    2012-12-20

    ... (EPCA) of 1975, as amended (42 U.S.C. 6291 et seq.), sets forth various provisions designed to improve... water heaters, and unfired hot water storage tanks); commercial refrigerators, freezers, and refrigerator-freezers; automatic commercial icemakers; commercial clothes washers; and walk-in coolers and walk...

  3. 27 CFR 70.65 - Use of commercial banks.

    Science.gov (United States)

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 2 2010-04-01 2010-04-01 false Use of commercial banks... Excise and Special (Occupational) Tax Receipt of Payment § 70.65 Use of commercial banks. For provisions relating to the use of commercial banks and electronic fund transfer of taxpayment to the Treasury Account...

  4. Diving Related Changes in the Blood Oxygen Stores of Rehabilitating Harbor Seal Pups (Phoca vitulina).

    Science.gov (United States)

    Thomas, Amber; Ono, Kathryn

    2015-01-01

    Harbor seal (Phoca vitulina) pups begin diving within hours of birth, stimulating the development of the blood oxygen (O2) stores necessary to sustain underwater aerobic metabolism. Since harbor seals experience a brief nursing period, the early-life development of these blood O2 stores is necessary for successful post-weaning foraging. If mothers and pups become prematurely separated, the pup may be transported to a wildlife rehabilitation center for care. Previous studies suggest that the shallow pools and lack of diving in rehabilitation facilities may lead to under-developed blood O2 stores, but diving behavior during rehabilitation has not been investigated. This study aimed to simultaneously study the diving behaviors and blood O2 store development of rehabilitating harbor seal pups. Standard hematology measurements (Hct, Hb, RBC, MCV, MCH, MCHC) were taken to investigate O2 storage capacity and pups were equipped with time-depth recorders to investigate natural diving behavior while in rehabilitation. Linear mixed models of the data indicate that all measured blood parameters changed with age; however, when compared to literature values for wild harbor seal pups, rehabilitating pups have smaller red blood cells (RBCs) that can store less hemoglobin (Hb) and subsequently, less O2, potentially limiting their diving capabilities. Wild pups completed longer dives at younger ages (maximum reported dives were observed (maximum during rehabilitation: 13.6 min at 89 days of age). Further, this study suggests that there may be a positive relationship between RBC size and the frequency of long duration dives. Thus, rehabilitating harbor seal pups should be encouraged to make frequent, long duration dives to prepare themselves for post-release foraging.

  5. The rat: a laboratory model for studies of the diving response

    Science.gov (United States)

    Gan, Qi; Juric, Rajko

    2010-01-01

    Underwater submersion in mammals induces apnea, parasympathetically mediated bradycardia, and sympathetically mediated peripheral vasoconstriction. These effects are collectively termed the diving response, potentially the most powerful autonomic reflex known. Although these physiological responses are directed by neurons in the brain, study of neural control of the diving response has been hampered since 1) it is difficult to study the brains of animals while they are underwater, 2) feral marine mammals are usually large and have brains of variable size, and 3) there are but few references on the brains of naturally diving species. Similar responses are elicited in anesthetized rodents after stimulation of their nasal mucosa, but this nasopharyngeal reflex has not been compared directly with natural diving behavior in the rat. In the present study, we compared hemodynamic responses elicited in awake rats during volitional underwater submersion with those of rats swimming on the water's surface, rats involuntarily submerged, and rats either anesthetized or decerebrate and stimulated nasally with ammonia vapors. We show that the hemodynamic changes to voluntary diving in the rat are similar to those of naturally diving marine mammals. We also show that the responses of voluntary diving rats are 1) significantly different from those seen during swimming, 2) generally similar to those elicited in trained rats involuntarily “dunked” underwater, and 3) generally different from those seen from dunking naive rats underwater. Nasal stimulation of anesthetized rats differed most from the hemodynamic variables of rats trained to dive voluntarily. We propose that the rat trained to dive underwater is an excellent laboratory model to study neural control of the mammalian diving response, and also suggest that some investigations may be done with nasal stimulation of decerebrate preparations to decipher such control. PMID:20093670

  6. Diving behavior and movements of juvenile hawksbill turtles Eretmochelys imbricata on a Caribbean coral reef

    Science.gov (United States)

    Blumenthal, J. M.; Austin, T. J.; Bothwell, J. B.; Broderick, A. C.; Ebanks-Petrie, G.; Olynik, J. R.; Orr, M. F.; Solomon, J. L.; Witt, M. J.; Godley, B. J.

    2009-03-01

    As historically abundant spongivores, hawksbill turtles Eretmochelys imbricata likely played a key ecological role on coral reefs. However, coral reefs are now experiencing global declines and many hawksbill populations are critically reduced. For endangered species, tracking movement has been recognized as fundamental to management. Since movements in marine vertebrates encompass three dimensions, evaluation of diving behavior and range is required to characterize marine turtle habitat. In this study, habitat use of hawksbill turtles on a Caribbean coral reef was elucidated by quantifying diel depth utilization and movements in relation to the boundaries of marine protected areas. Time depth recorders (TDRs) and ultrasonic tags were deployed on 21 Cayman Islands hawksbills, ranging in size from 26.4 to 58.4 cm straight carapace length. Study animals displayed pronounced diel patterns of diurnal activity and nocturnal resting, where diurnal dives were significantly shorter, deeper, and more active. Mean diurnal dive depth (±SD) was 8 ± 5 m, range 2-20 m, mean nocturnal dive depth was 5 ± 5 m, range 1-14 m, and maximum diurnal dive depth was 43 ± 27 m, range 7-91 m. Larger individuals performed significantly longer dives. Body mass was significantly correlated with mean dive depth for nocturnal but not diurnal dives. However, maximum diurnal dive depth was significantly correlated with body mass, suggesting partitioning of vertical habitat by size. Thus, variable dive capacity may reduce intraspecific competition and provide resistance to degradation in shallow habitats. Larger hawksbills may also represent important predators on deep reefs, creating a broad ecological footprint over a range of depths.

  7. Drift dives and prolonged surfacing periods in Baikal seals: resting strategies in open waters?

    Science.gov (United States)

    Watanabe, Yuuki Y; Baranov, Eugene A; Miyazaki, Nobuyuki

    2015-09-01

    Many pinnipeds frequently rest on land or ice, but some species remain in open waters for weeks or months, raising the question of how they rest. A unique type of dive, called drift dives, has been reported for several pinnipeds with suggested functions of rest, food processing and predator avoidance. Prolonged surfacing periods have also been observed in captive seals and are thought to aid food processing. However, information from other species in a different environment would be required to better understand the nature and function of this behavior. In this study, we attached multi-sensor tags to Baikal seals Pusa sibirica, a rare, freshwater species that has no aquatic predators and few resting grounds during the ice-free season. The seals exhibited repeated drift dives (mean depth, 116 m; duration, 10.1 min) in the daytime and prolonged periods at the surface (mean duration, 1.3 h) mainly around dawn. Drift dives and prolonged surfacing periods were temporally associated and observed between a series of foraging dives, suggesting a similar function, i.e. a combination of resting and food processing. The maximum durations of both drift and foraging dives were 15.4 min, close to the aerobic dive limit of this species; therefore, metabolic rates might not be significantly depressed during drift dives, further supporting the function of food processing rather than purely resting. Our results also show that drift diving can occur in a predator-free environment, and thus predator avoidance is not a general explanation of drift dives in pinnipeds. © 2015. Published by The Company of Biologists Ltd.

  8. Diving Related Changes in the Blood Oxygen Stores of Rehabilitating Harbor Seal Pups (Phoca vitulina.

    Directory of Open Access Journals (Sweden)

    Amber Thomas

    Full Text Available Harbor seal (Phoca vitulina pups begin diving within hours of birth, stimulating the development of the blood oxygen (O2 stores necessary to sustain underwater aerobic metabolism. Since harbor seals experience a brief nursing period, the early-life development of these blood O2 stores is necessary for successful post-weaning foraging. If mothers and pups become prematurely separated, the pup may be transported to a wildlife rehabilitation center for care. Previous studies suggest that the shallow pools and lack of diving in rehabilitation facilities may lead to under-developed blood O2 stores, but diving behavior during rehabilitation has not been investigated. This study aimed to simultaneously study the diving behaviors and blood O2 store development of rehabilitating harbor seal pups. Standard hematology measurements (Hct, Hb, RBC, MCV, MCH, MCHC were taken to investigate O2 storage capacity and pups were equipped with time-depth recorders to investigate natural diving behavior while in rehabilitation. Linear mixed models of the data indicate that all measured blood parameters changed with age; however, when compared to literature values for wild harbor seal pups, rehabilitating pups have smaller red blood cells (RBCs that can store less hemoglobin (Hb and subsequently, less O2, potentially limiting their diving capabilities. Wild pups completed longer dives at younger ages (maximum reported <25 days of age: 9 min in previous studies than the captive pups in this study (maximum <25 days of age: 2.86 min. However, captivity may only affect the rate of development, as long duration dives were observed (maximum during rehabilitation: 13.6 min at 89 days of age. Further, this study suggests that there may be a positive relationship between RBC size and the frequency of long duration dives. Thus, rehabilitating harbor seal pups should be encouraged to make frequent, long duration dives to prepare themselves for post-release foraging.

  9. Assessment of extravascular lung water and cardiac function in trimix SCUBA diving.

    Science.gov (United States)

    Marinovic, Jasna; Ljubkovic, Marko; Obad, Ante; Breskovic, Toni; Salamunic, Ilza; Denoble, Petar J; Dujic, Zeljko

    2010-06-01

    An increasing number of recreational self-contained underwater breathing apparatus (SCUBA) divers use trimix of oxygen, helium, and nitrogen for dives deeper than 60 m of sea water. Although it was seldom linked to the development of pulmonary edema, whether SCUBA diving affects the extravascular lung water (EVLW) accumulation is largely unexplored. Seven divers performed six dives on consecutive days using compressed gas mixture of oxygen, helium, and nitrogen (trimix), with diving depths ranging from 55 to 80 m. The echocardiographic parameters (bubble grade, lung comets, mean pulmonary arterial pressure (PAP), and left ventricular function) and the blood levels of the N-terminal part of pro-brain natriuretic peptide (NT-proBNP) were assessed before and after each dive. Venous gas bubbling was detected after each dive with mean probability of decompression sickness ranging from 1.77% to 3.12%. After each dive, several ultrasonographically detected lung comets rose significantly, which was paralleled by increased pulmonary artery pressure (PAP) and decreased left ventricular contractility (reduced ejection fraction at higher end-systolic and end-diastolic volumes) as well as the elevated NT-proBNP. The number of ultrasound lung comets and mean PAP did not return to baseline values after each dive. This is the first report that asymptomatic SCUBA dives are associated with accumulation of EVLW with concomitant increase in PAP, diminished left ventricular contractility, and increased release of NT-proBNP, suggesting a significant cardiopulmonary strain. EVLW and PAP did not return to baseline during repetitive dives, indicating possible cumulative effect with increasing the risk for pulmonary edema.

  10. Successive deep dives impair endothelial function and enhance oxidative stress in man.

    Science.gov (United States)

    Obad, Ante; Marinovic, Jasna; Ljubkovic, Marko; Breskovic, Toni; Modun, Darko; Boban, Mladen; Dujic, Zeljko

    2010-11-01

    The aim of this study was to assess the effects of successive deep dives on endothelial function of large conduit arteries and plasma pro-oxidant and antioxidant activity. Seven experienced divers performed six dives in six consecutive days using a compressed mixture of oxygen, helium and nitrogen (trimix) with diving depths ranging from 55 to 80 m. Before and after first, third and sixth dive, venous gas emboli formation and brachial artery function (flow-mediated dilation, FMD) was assessed by ultrasound. In addition, plasma antioxidant capacity (AOC) was measured by ferric reducing antioxidant power, and the level of oxidative stress was assessed by thiobarbituric acid-reactive substances (TBARS) method. Although the FMD was reduced to a similar extent after each dive, the comparison of predive FMD showed a reduction from 8.6% recorded before the first dive to 6.3% before the third (P = 0.03) and 5.7% before the sixth dive (P = 0.003). A gradual shift in baseline was also detected with TBARS assay, with malondialdehyde values increasing from 0.10 ± 0.02 μmol l⁻¹ before the first dive to 0.16 ± 0.03 before the sixth (P = 0.005). Predive plasma AOC values also showed a decreasing trend from 0.67 ± 0.20 mmol l⁻¹ trolox equivalents (first day) to 0.56 ± 0.12 (sixth day), although statistical significance was not reached (P = 0.08). This is the first documentation of acute endothelial dysfunction in the large conduit arteries occurring after successive deep trimix dives. Both endothelial function and plasma pro-oxidant and antioxidant activity did not return to baseline during the course of repetitive dives, indicating possible cumulative and longer lasting detrimental effects. © 2010 The Authors. Clinical Physiology and Functional Imaging © 2010 Scandinavian Society of Clinical Physiology and Nuclear Medicine.

  11. Haemodynamic changes induced by submaximal exercise before a dive and its consequences on bubble formation

    Science.gov (United States)

    Blatteau, Jean‐Eric; Boussuges, Alain; Gempp, Emmanuel; Pontier, Jean‐Michel; Castagna, Olivier; Robinet, Claude; Galland, Francois‐Michel; Bourdon, Lionel

    2007-01-01

    Objectives To evaluate the effects of a submaximal exercise performed 2 h before a simulated dive on bubble formation and to observe the haemodynamic changes and their influence on bubble formation. Participants and methods 16 trained divers were compressed in a hyperbaric chamber to 400 kPa for 30 min and decompressed at a rate of 100 kPa/min with a 9 min stop at 130 kPa (French Navy MN90 procedure). Each diver performed two dives 3 days apart, one without exercise and one with exercise before the dive. All participants performed a 40 min constant‐load submaximal and calibrated exercise, which consisted of outdoor running 2 h before the dive. Circulating bubbles were detected with a precordial Doppler at 30, 60 and 90 min after surfacing. Haemodynamic changes were evaluated with Doppler echocardiography. Results A single bout of strenuous exercise 2 h before a simulated dive significantly reduced circulating bubbles. Post‐exercise hypotension (PEH) was observed after exercise with reductions in diastolic and mean blood pressure (DBP and MBP), but total peripheral resistance was unchanged. Stroke volume was reduced, whereas cardiac output was unchanged. Simulated diving caused a similar reduction in cardiac output independent of pre‐dive exercise, suggesting that pre‐dive exercise only changed DBP and MBP caused by reduced stroke volume. Conclusion A single bout of strenuous exercise 2 h before a dive significantly reduced the number of bubbles in the right heart of divers and protected them from decompression sickness. Declining stroke volume and moderate dehydration induced by a pre‐dive exercise might influence inert gas load and bubble formation. PMID:17138641

  12. Venous gas emboli are involved in post-dive macro, but not microvascular dysfunction.

    Science.gov (United States)

    Lambrechts, Kate; Balestra, Costantino; Theron, Michaël; Henckes, Anne; Galinat, Hubert; Mignant, Fanny; Belhomme, Marc; Pontier, Jean-Michel; Guerrero, François

    2017-02-01

    Previous studies have shown vascular dysfunction of main conductance arteries and microvessels after diving. We aim to evaluate the impact of bubble formation on vascular function and haemostasis. To achieve this, we used a vibration preconditioning to influence bubble levels without changing any other parameters linked to the dive. Twentty-six divers were randomly assigned to one of three groups: (1) the "vibrations-dive" group (VD; n = 9) was exposed to a whole-body vibration session 30 min prior the dive; (2) the "diving" group (D; n = 9) served as a control for the effect of the diving protocol; (3) The "vibration" protocol (V; n = 8) allowed us to assess the effect of vibrations without diving. Macro- and microvascular function was assessed for each subject before and after the dive, subsequently. Bubble grades were monitored with Doppler according to the Spencer grading system. Blood was taken before and after the protocol to assess any change of platelets or endothelial function. Bubble formation was lower in the VD than the diving group. The other measured parameters remained unchanged after the "vibration" protocol alone. Diving alone induced macrovascular dysfunction, and increased PMP and thrombin generation. Those parameters were no longer changed in the VD group. Conversely, a microvascular dysfunction persists despite a significant decrease of circulating bubbles. Finally, the results of this study suggest that macro- but not microvascular impairment results at least partly from bubbles, possibly related to platelet activation and generation of pro-coagulant microparticles.

  13. Diving behavior of sperm whales in relation to behavior of a major prey species, the jumbo squid, in the Gulf of California, Mexico

    OpenAIRE

    Gilly, W.; Bazzino, G.; Markaida, U.; Gendron, Diane; Jaquet, N; Davis, R.W.

    2007-01-01

    Sperm whales occur worldwide and feed largely on meso- and bathypelagic squid, but little is known about the behavioral ecology of this predator and its prey. In the Gulf of California, sperm whales are thought to feed on the abundant jumbo (Humboldt) squid, an ecologically and commercially important species. In this study, we attached satellite-linked dive recorders to 5 sperm whales and pop-up archival transmitting tags to 3 jumbo squid in the same area and time period in order to record th...

  14. Superior canal dehiscence syndrome associated with scuba diving.

    Science.gov (United States)

    Kitajima, Naoharu; Sugita-Kitajima, Akemi; Kitajima, Seiji

    2017-06-01

    A 28-year-old female diver presented with dizziness and difficulty clearing her left ear whilst scuba diving. Her pure-tone audiometry and tympanometry were normal. Testing of Eustachian tube function revealed tubal stenosis. Video-oculography revealed a predominantly torsional nystagmus while the patient was in the lordotic position. Fistula signs were positive. High-resolution computed tomography (HRCT) of the temporal bone revealed a diagnosis of bilateral superior semicircular canal dehiscence (SCDS). Cervical vestibular-evoked myogenic potential (cVEMP) testing showed that the amplitude of the cVEMP measured from her left ear was larger than that from the right. In electronystagmography (ENG), nose-pinched Valsalva manoeuvres caused eye movements to be mainly directed counterclockwise with a vertical component. Tullio phenomenon was also positive for both ears. SCDS patients tend to be misdiagnosed and misunderstood; common misdiagnoses in these cases are alternobaric vertigo (AV), inner ear barotrauma, and inner-ear decompression sickness. It is difficult to diagnose vertigo attacks after scuba diving as SCDS; however, when the patient develops sound- and/or pressure-induced vertical-torsional nystagmus, HRCT should be conducted to confirm a diagnosis of SCDS.

  15. Dumpster diving: Mezi etikou a zákonem

    Directory of Open Access Journals (Sweden)

    Jana Kliková

    2017-06-01

    Full Text Available The aim of this paper is to reflect on the ethical dilemma of researchers who encounter illegal activity during their research, or of researchers who are particularly interested in this kind of activity. The inspiration comes from research that we are currently conducting on dumpster diving as a source of creativity. We interview people in the Pilsen Region who pursue this activity, or who used to do so. Although dumpster diving is becoming more popular, it is not legal. Waste remains tangible property and therefore always belongs to someone. For this reason, its appropriation is not in agreement with the law. According to the codes of ethics of various anthropological associations, the researcher should always be mindful of respecting the privacy and safety of the people the researcher is scientifically interested in. This could be a significant problem in cases where the anthropologist witnesses an illegal activity. Since the law is formally superior to an ethical code, the researcher should notify the police, especially if the activity in question is subject to the duty to report a crime. The question is how to cope with this “ethically important moment in research” (Guillemin and Gillam 2004, 262.

  16. Extreme diving behaviour in devil rays links surface waters and the deep ocean

    KAUST Repository

    Thorrold, Simon R.

    2014-07-01

    Ecological connections between surface waters and the deep ocean remain poorly studied despite the high biomass of fishes and squids residing at depths beyond the euphotic zone. These animals likely support pelagic food webs containing a suite of predators that include commercially important fishes and marine mammals. Here we deploy pop-up satellite archival transmitting tags on 15 Chilean devil rays (Mobula tarapacana) in the central North Atlantic Ocean, which provide movement patterns of individuals for up to 9 months. Devil rays were considered surface dwellers but our data reveal individuals descending at speeds up to 6.0 ms-1 to depths of almost 2,000 m and water temperatures <4 C. The shape of the dive profiles suggests that the rays are foraging at these depths in deep scattering layers. Our results provide evidence of an important link between predators in the surface ocean and forage species occupying pelagic habitats below the euphotic zone in ocean ecosystems. 2014 Macmillan Publishers Limited. All rights reserved.

  17. Extreme diving behaviour in devil rays links surface waters and the deep ocean.

    Science.gov (United States)

    Thorrold, Simon R; Afonso, Pedro; Fontes, Jorge; Braun, Camrin D; Santos, Ricardo S; Skomal, Gregory B; Berumen, Michael L

    2014-07-01

    Ecological connections between surface waters and the deep ocean remain poorly studied despite the high biomass of fishes and squids residing at depths beyond the euphotic zone. These animals likely support pelagic food webs containing a suite of predators that include commercially important fishes and marine mammals. Here we deploy pop-up satellite archival transmitting tags on 15 Chilean devil rays (Mobula tarapacana) in the central North Atlantic Ocean, which provide movement patterns of individuals for up to 9 months. Devil rays were considered surface dwellers but our data reveal individuals descending at speeds up to 6.0 m s(-1) to depths of almost 2,000 m and water temperatures <4 °C. The shape of the dive profiles suggests that the rays are foraging at these depths in deep scattering layers. Our results provide evidence of an important link between predators in the surface ocean and forage species occupying pelagic habitats below the euphotic zone in ocean ecosystems.

  18. Dive and Explore: An Interactive Exhibit That Simulates Making an ROV Dive to a Submarine Volcano, Hatfield Marine Science Visitor Center, Newport, Oregon

    Science.gov (United States)

    Weiland, C.; Chadwick, W. W.; Hanshumaker, W.; Osis, V.; Hamilton, C.

    2002-12-01

    We have created a new interactive exhibit in which the user can sit down and simulate that they are making a dive to the seafloor with the remotely operated vehicle (ROV) named ROPOS. The exhibit immerses the user in an interactive experience that is naturally fun but also educational. This new public display is located at the Hatfield Marine Science Visitor Center in Newport, Oregon. The exhibit is designed to look like the real ROPOS control console and includes three video monitors, a PC, a DVD player, an overhead speaker, graphic panels, buttons, lights, dials, and a seat in front of a joystick. The dives are based on real seafloor settings at Axial seamount, an active submarine volcano on the Juan de Fuca Ridge (NE Pacific) that is also the location of a seafloor observatory called NeMO. The user can choose between 1 of 3 different dives sites in the caldera of Axial Volcano. Once a dive is chosen, then the user watches ROPOS being deployed and then arrives into a 3-D computer-generated seafloor environment that is based on the real world but is easier to visualize and navigate. Once on the bottom, the user is placed within a 360 degree panorama and can look in all directions by manipulating the joystick. By clicking on markers embedded in the scene, the user can then either move to other panorama locations via movies that travel through the 3-D virtual environment, or they can play video clips from actual ROPOS dives specifically related to that scene. Audio accompanying the video clips informs the user where they are going or what they are looking at. After the user is finished exploring the dive site they end the dive by leaving the bottom and watching the ROV being recovered onto the ship at the surface. The user can then choose a different dive or make the same dive again. Within the three simulated dives there are a total of 6 arrival and departure movies, 7 seafloor panoramas, 12 travel movies, and 23 ROPOS video clips. The exhibit software was created

  19. 12-lead Holter monitoring in diving and water sports: a preliminary investigation.

    Science.gov (United States)

    Bosco, Gerardo; De Marzi, Elena; Michieli, Pierantonio; Omar, Hesham R; Camporesi, Enrico M; Padulo, Johnny; Paoli, Antonio; Mangar, Devanand; Schiavon, Maurizio

    2014-12-01

    To demonstrate the utility of 12-lead Holter monitoring underwater. A Holter monitor, recording a 12-lead electrocardiogram (ECG) underwater, was applied to 16 pre-trained volunteer scuba divers (13 males and three females). Dive computers were synchronized with the Holter recorder to correlate the ECG tracings with diving events. Our main objective was to demonstrate the utility of recording over a period of time a good quality 12-lead ECG underwater. The ECGs were analyzed for heart rate (HR), arrhythmias, conduction abnormalities and ischaemic events in relation to various stages of diving as follows: baseline, pre diving, diving, and post diving. The ECG tracings were of good quality with minimal artefacts. Analysis of variance (ANOVA) demonstrated a significant difference in HR during the various diving stages (P < 0.0001). Other recorded ECG abnormalities included supraventricular ectopic beats (four cases), ventricular ectopic beats (eight cases) and ventricular couplets (two cases). Conduction abnormalities included rate-dependent right and left bundle branch block; however, these findings were previously known in these divers. No evidence of ischaemia was seen. Continuous 12-lead Holter monitoring underwater can produce good quality tracings. Further studies are necessary to assess its usefulness in divers at risk for or with known coronary artery disease, and its comparison with other forms of cardiac stress tests.

  20. Recreational scuba diving: negative or positive effects of oxidative and cardiovascular stress?

    Science.gov (United States)

    Perovic, Antonija; Unic, Adriana; Dumic, Jerka

    2014-01-01

    Environmental conditions and increased physical activity during scuba diving are followed by increased production of free radicals and disturbed redox balance. Redox balance disorder is associated with damage of cellular components, changes of cellular signaling pathways and alterations of gene expression. Oxidative stress leads to increased expression of sirtuins (SIRTs), molecules which play an important role in the antioxidant defense, due to their sensitivity to the changes in the redox status and their ability to regulate redox homeostasis. These facts make SIRTs interesting to be considered as molecules affected by scuba diving and in that sense, as potential biomarkers of oxidative status or possible drug targets in reduction of reactive oxygen species (ROS) accumulation. In addition, SIRTs effects through currently known targets make them intriguing molecules which can act positively on health in general and whose expression can be induced by scuba diving.A demanding physical activity, as well as other circumstances present in scuba diving, has the greatest load on the cardiovascular function (CV). The mechanisms of CV response during scuba diving are still unclear, but diving-induced oxidative stress and the increase in SIRTs expression could be an important factor in CV adaptation. This review summarizes current knowledge on scuba diving-induced oxidative and CV stress and describes the important roles of SIRTs in the (patho)physiological processes caused by the redox balance disorder.

  1. Body contact and synchronous diving in long-finned pilot whales.

    Science.gov (United States)

    Aoki, Kagari; Sakai, Mai; Miller, Patrick J O; Visser, Fleur; Sato, Katsufumi

    2013-10-01

    Synchronous behavior, as a form of social interaction, has been widely reported for odontocete cetaceans observed at the sea surface. However, few studies have quantified synchronous behavior underwater. Using data from an animal-borne data recorder and camera, we described how a pair of deep-diving odontocetes, long-finned pilot whales, coordinated diving behavior. Diving data during overlapping periods of 3.7 h were obtained from two whales within a stable trio. The tagged whales made highly synchronous movements, and their dive durations differed only slightly (3±3 s). The pair of whales maintained a constant and narrow vertical separation (ca. 3 m) throughout synchronous dives. The overall fluking rate for the same travel speed during synchronous dives was virtually the same as that during asynchronous dives, suggesting that synchronous behavior did not affect locomotion effort. In addition, a possible affiliative behavior was recorded by the animal-borne camera: another individual appeared in 8% of the frames, both with and without body contact to the tagged whale. The primary type of body contact was flipper-to-body. Our study, the first on underwater synchronous behavior and body contact of pilot whales, highlights the utility of using animal-borne devices for enabling new insights into social interactions. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. The comparative biology of diving in two genera of European Dytiscidae (Coleoptera).

    Science.gov (United States)

    Calosi, P; Bilton, D T; Spicer, J I; Verberk, W C E P; Atfield, A; Garland, T

    2012-02-01

    Surfacing behaviour is fundamental in the ecology of aquatic air-breathing organisms; however, it is only in vertebrates that the evolutionary ecology of diving has been well characterized. Here, we explore the diving behaviour of dytiscid beetles, a key group of surface-exchanging freshwater invertebrates, by comparing the dive responses of 25 taxa (Deronectes and Ilybius spp.) acclimated at two temperatures. The allometric slopes of dive responses in these dytiscids appear similar to those of vertebrate ectotherms, supporting the notion that metabolic mode shapes the evolution of diving performance. In both genera, beetles spend more time submerged than on the surface, and surface time does not vary with the temperature of acclimation. However, presumably in order to meet increased oxygen demand at higher temperatures, Deronectes species increase surfacing frequency, whereas Ilybius species decrease dive time, an example of 'multiple solutions.' Finally, widespread northern species appear to possess higher diving performances than their geographically restricted southern relatives, something which may have contributed to their range expansion ability. © 2011 The Authors. Journal of Evolutionary Biology © 2011 European Society For Evolutionary Biology.

  3. Children’s Understanding of No Diving Warning Signs: Implications for Preventing Childhood Injury

    Directory of Open Access Journals (Sweden)

    Barbara A. Morrongiello

    2016-07-01

    Full Text Available The current study examined children’s understanding of No Diving warning signs. Normally-developing 7 to 10 year olds were asked questions to assess their understanding of text, images, and main messages on No Diving warning signs. These structured interviews were audio recorded and responses were later coded. Results revealed that children understood the behavior advised against (diving, why it is prohibited (can hit head on the bottom, and what can happen (serious injury including hospitalization. They understood that breaking your neck results in limitations in mobility and can occur from diving, but they did not anticipate that such an injury is likely to occur. There were no gender and few age differences, but diving experience was associated with children significantly downplaying their risk of injury. The findings suggest that having No Diving warning signs explicitly mention a broken neck, may serve to remind children of this potential consequence at the time of decision making. Active adult supervision is particularly important for children who have prior positive diving experiences.

  4. Dive characteristics can predict foraging success in Australian fur seals (Arctocephalus pusillus doriferus as validated by animal-borne video

    Directory of Open Access Journals (Sweden)

    Beth L. Volpov

    2016-03-01

    Full Text Available Dive characteristics and dive shape are often used to infer foraging success in pinnipeds. However, these inferences have not been directly validated in the field with video, and it remains unclear if this method can be applied to benthic foraging animals. This study assessed the ability of dive characteristics from time-depth recorders (TDR to predict attempted prey capture events (APC that were directly observed on animal-borne video in Australian fur seals (Arctocephalus pusillus doriferus, n=11. The most parsimonious model predicting the probability of a dive with ≥1 APC on video included only descent rate as a predictor variable. The majority (94% of the 389 total APC were successful, and the majority of the dives (68% contained at least one successful APC. The best model predicting these successful dives included descent rate as a predictor. Comparisons of the TDR model predictions to video yielded a maximum accuracy of 77.5% in classifying dives as either APC or non-APC or 77.1% in classifying dives as successful verses unsuccessful. Foraging intensity, measured as either total APC per dive or total successful APC per dive, was best predicted by bottom duration and ascent rate. The accuracy in predicting total APC per dive varied based on the number of APC per dive with maximum accuracy occurring at 1 APC for both total (54% and only successful APC (52%. Results from this study linking verified foraging dives to dive characteristics potentially opens the door to decades of historical TDR datasets across several otariid species.

  5. Animal Models for Investigating the Central Control of the Mammalian Diving Response

    Science.gov (United States)

    McCulloch, Paul Frederick

    2012-01-01

    Pioneering studies by Per Scholander indicated that the diving response consists of reflexly induced apnea, bradycardia and an alteration of blood flow that maintains perfusion of the heart and brain. More recently field physiological studies have shown that many marine animals can adjust cardiorespiratory aspects of their diving response depending upon the behavioral situation. This could suggest that the very labile heart rate during diving is under direct cortical control. However, the final control of autonomic nervous system functioning resides within the brainstem and not the cortex. Many physiologists regard the brain as a “black box” where important neuronal functioning occurs, but the complexity of such functioning leaves systematic investigation a daunting task. As a consequence the central control of the diving response has been under-investigated. Thus, to further advance the field of diving physiology by understanding its central neuronal control, it would be first necessary to understand the reflex circuitry that exists within the brainstem of diving animals. To do this will require an appropriate animal model. In this review, two animals, the muskrat and rat, will be offered as animal models to investigate the central aspects of the diving response. Firstly, although these rodents are not marine animals, natural histories indicate that both animals can and do exploit aquatic environments. Secondly, physiological recordings during natural and simulated diving indicate that both animals possess the same basic physiological responses to underwater submersion that occur in marine animals. Thirdly, the size and ease of housing of both animals makes them attractive laboratory research animals. Finally, the enormous amount of scientific literature regarding rodent brainstem autonomic control mechanisms, and the availability of brain atlases, makes these animals ideal choices to study the central control of the mammalian diving response. PMID:22661956

  6. Effects of hyperbaric oxygen preconditioning on cardiac stress markers after simulated diving

    Science.gov (United States)

    Jørgensen, Arve; Foster, Philip P; Brubakk, Alf O; Eftedal, Ingrid

    2013-01-01

    Hyperbaric oxygen preconditioning (HBO-PC) can protect the heart from injury during subsequent ischemia. The presence of high loads of venous gas emboli (VGE) induced by a rapid ambient pressure reduction on ascent from diving may cause ischemia and acute heart failure. The aim of this study was to investigate the effect of diving-induced VGE formation on cardiac stress marker levels and the cardioprotective effect of HBO-PC. To induce high loads of VGE, 63 female Sprague–Dawley rats were subjected to a rapid ambient pressure reduction from a simulated saturation dive (50 min at 709 kPa) in a pressure chamber. VGE loads were measured for 60 min in anesthetized animals by the use of ultrasonography. The animals were divided into five groups. Three groups were exposed to either diving or to HBO-PC (100% oxygen, 38 min at 303 kPa) with a 45 or 180 min interval between HBO-PC and diving. Two additional groups were used as baseline controls for the measurements; one group was exposed to equal handling except for HBO-PC and diving, and the other group was completely unexposed. Diving caused high loads of VGE, as well as elevated levels of the cardiac stress markers, cardiac troponin T (cTnT), natriuretic peptide precursor B (Nppb), and αB-crystallin, in blood and cardiac tissue. There were strong positive correlations between VGE loads and stress marker levels after diving, and HBO-PC appeared to have a cardioprotective effect, as indicated by the lower levels of stress marker expression after diving-induced VGE formation. PMID:24400168

  7. A new method to quantify within dive foraging behaviour in marine predators.

    Directory of Open Access Journals (Sweden)

    Karine Heerah

    Full Text Available Studies on diving behaviour classically divide a dive into three phases: the descent, bottom and ascent phases, with foraging assumed to occur during the bottom phase. The greater complexity of dive revealed through modern, high resolution data highlights the need to re-assess this approach and to consider a larger number of phases within individual dives. Two southern elephant seals (SES were fitted with a head mounted Time Depth Recorder (TDR and an accelerometer from which prey capture attempts were estimated. A Weddell seal was also fitted with a TDR. TDRs for both species recorded depth once per second. We quantified the within dive behaviour using an automated broken stick algorithm identifying the optimal number of segments within each dive. The vertical sinuosity of the segments was used to infer two types of behaviours, with highly sinuous segments indicating "hunting" and less sinuous segments indicating "transiting". Using the broken stick method the seals alternated between "hunting" and "transit" modes with an average of 6±2 and 7±0.02 behavioural phases within each dive for the Weddell seal and SES, respectively. In SES, 77% of prey capture attempts (identified from the acceleration data occurred in highly sinuous phases ("hunting" as defined by our new approach. SES spent more time in transit mode within a dive, and hunting mostly occurred during the bottom phase. Conversely the Weddell seal spent more time in hunting mode which also occurred during bottom phase but occurred mostly at shallower depths. Such differences probably reflect different foraging tactics and habitat use. For both species, hunting time differs significantly from bottom time previously used as a proxy for the time spent foraging in a dive. The hunting time defined by our method therefore provides a more accurate fine-scale description of the seals' foraging behaviour.

  8. DIVE: a graph-based visual-analytics framework for big data.

    Science.gov (United States)

    Rysavy, Steven J; Bromley, Dennis; Daggett, Valerie

    2014-01-01

    The need for data-centric scientific tools is growing; domains such as biology, chemistry, and physics are increasingly adopting computational approaches. So, scientists must deal with the challenges of big data. To address these challenges, researchers built a visual-analytics platform named DIVE (Data Intensive Visualization Engine). DIVE is a data-agnostic, ontologically expressive software framework that can stream large datasets at interactive speeds. In particular, DIVE makes novel contributions to structured-data-model manipulation and high-throughput streaming of large, structured datasets.

  9. Aerobic dive limits of seals with mutant myoglobin using combined thermochemical and physiological data

    DEFF Research Database (Denmark)

    Dasmeh, Pouria; Davis, Randall W.; Kepp, Kasper Planeta

    2013-01-01

    This paper presents an integrated model of convective O2-transport, aerobic dive limits (ADL), and thermochemical data for oxygen binding to mutant myoglobin (Mb), used to quantify the impact of mutations in Mb on the dive limits of Weddell seals (Leptonychotes weddellii). We find that wild-type Mb...... traits are only superior under specific behavioral and physiological conditions that critically prolong the ADL, action radius, and fitness of the seals. As an extreme example, the mutations in the conserved His-64 reduce ADL up to 14±2 min for routine aerobic dives, whereas many other mutations...

  10. PROVISIONS – ACCOUNTING TOOLS OF RISK MITIGATION ECONOMIC

    Directory of Open Access Journals (Sweden)

    Lucica SINTEA (ANGHEL

    2016-07-01

    Full Text Available Provisions represent a defense of the economic entity against the risks they may face. These have an important role in funding decisions that will be taken in future when it is desirable an absorption fusion in the establishment or when it is desirable concluding contracts and /or commercial banking. As more provisions are created, even more protected, the company credibility with partners is higher. Any investor is interested in the transparency of accounts as they are the real economic picture of the entity and the basis from which to start making management decisions. Constituting provisions is accomplished after the inventory of patrimonial.

  11. Virtual Diving in the Underwater Archaeological Site of Cala Minnola

    Science.gov (United States)

    Bruno, F.; Lagudi, A.; Barbieri, L.; Muzzupappa, M.; Mangeruga, M.; Pupo, F.; Cozza, M.; Cozza, A.; Ritacco, G.; Peluso, R.; Tusa, S.

    2017-02-01

    The paper presents the application of the technologies and methods defined in the VISAS project for the case study of the underwater archaeological site of Cala Minnola located in the island of Levanzo, in the archipelago of the Aegadian Islands (Sicily, Italy). The VISAS project (http://visas-project.eu) aims to improve the responsible and sustainable exploitation of the Underwater Cultural Heritage by means the development of new methods and technologies including an innovative virtual tour of the submerged archaeological sites. In particular, the paper describes the 3D reconstruction of the underwater archaeological site of Cala Minnola and focus on the development of the virtual scene for its visualization and exploitation. The virtual dive of the underwater archaeological site allows users to live a recreational and educational experience by receiving historical, archaeological and biological information about the submerged exhibits, the flora and fauna of the place.

  12. A case of deep burns, while diving The Lusitania.

    LENUS (Irish Health Repository)

    Curran, John N

    2010-07-01

    We present the first documented case of severe burns, sustained by a diver as a result of auto-ignition of air-activated heat packs at high partial pressure of oxygen and high ambient pressure. Our patient was diving the shipwreck of The Lusitania off the south coast of Ireland. This is a significant wreck, lying 90 metres down on the seabed. Torpedoed by a German U-boat in 1915, its loss prompted American involvement in WW1. Several unlikely events combined in this case to bring about serious and life threatening injuries. Herein we discuss the case and explore some of the physical and chemical processes that lead to these injuries.

  13. The surface activity of pulmonary surfactant from diving mammals.

    Science.gov (United States)

    Miller, Natalie J; Daniels, Christopher B; Schürch, Samuel; Schoel, W Michael; Orgeig, Sandra

    2006-02-28

    Pinnipeds (seals and sea lions) have developed a specialised respiratory system to cope with living in a marine environment. They have a highly reinforced lung that can completely collapse and reinflate during diving without any apparent side effects. These animals may also have a specialised surfactant system to augment the morphological adaptations. The surface activity of surfactant from four species of pinniped (California sea lion, Northern elephant seal, Northern fur seal and Ringed seal) was measured using a captive bubble surfactometer (CBS), and compared to two terrestrial species (sheep and cow). The surfactant of Northern elephant seal, Northern fur seal and Ringed seal was unable to reduce surface tension (gamma) to normal levels after 5 min adsorption (61.2, 36.7, and 46.2 +/- 1.7 mN/m, respectively), but California sea lion was able to reach the levels of the cow and sheep (23.4 mN/m for California sea lion, 21.6 +/- 0.3 and 23.0 +/- 1.5 mN/m for cow and sheep, respectively). All pinnipeds were also unable to obtain the very low gamma(min) achieved by cow (1.4 +/- 0.1 mN/m) and sheep (1.5 +/- 0.4 mN/m). These results suggest that reducing surface tension to very low values is not the primary function of surfactant in pinnipeds as it is in terrestrial mammals, but that an anti-adhesive surfactant is more important to enable the lungs to reopen following collapse during deep diving.

  14. Epilepsy and recreational scuba diving: an absolute contraindication or can there be exceptions? A call for discussion.

    Science.gov (United States)

    Almeida, Maria do Rosario G; Bell, Gail S; Sander, Josemir W

    2007-05-01

    Recreational scuba diving is a popular sport, and people with epilepsy often ask physicians whether they may engage in diving. Scuba diving is not, however, without risk for anyone; apart from the risk of drowning, the main physiological problems, caused by exposure to gases at depth, are decompression illness, oxygen toxicity, and nitrogen narcosis. In the United Kingdom, the Sport Diving Medical Committee advises that, to dive, someone with epilepsy must be seizure free and off medication for at least 5 years. The reasons for this are largely theoretical. We review the available evidence in the medical literature and diving websites. The risk of seizures recurring decreases with increasing time in remission, but the risk is never completely abolished. We suggest that people with epilepsy who wish to engage in diving, and the physicians who certify fitness to dive, should be provided with all the available evidence. Those who have been entirely seizure-free on stable antiepileptic drug therapy for at least 4 years, who are not taking sedative antiepileptic drugs and who are able to understand the risks, should then be able to consider diving to shallow depths, provided both they and their diving buddy have fully understood the risks.

  15. Commercial applications

    Science.gov (United States)

    The near term (one to five year) needs of domestic and foreign commercial suppliers of radiochemicals and radiopharmaceuticals for electromagnetically separated stable isotopes are assessed. Only isotopes purchased to make products for sale and profit are considered. Radiopharmaceuticals produced from enriched stable isotopes supplied by the Calutron facility at ORNL are used in about 600,000 medical procedures each year in the United States. A temporary or permanent disruption of the supply of stable isotopes to the domestic radiopharmaceutical industry could curtail, if not eliminate, the use of such diagnostic procedures as the thallium heart scan, the gallium cancer scan, the gallium abscess scan, and the low radiation dose thyroid scan. An alternative source of enriched stable isotopes exist in the USSR. Alternative starting materials could, in theory, eventually be developed for both the thallium and gallium scans. The development of a new technology for these purposes, however, would take at least five years and would be expensive. Hence, any disruption of the supply of enriched isotopes from ORNL and the resulting unavailability of critical nuclear medicine procedures would have a dramatic negative effect on the level of health care in the United States.

  16. Submersible Data (Dive Trackpoints) for Bioluminescence 2009 - Office of Ocean Exploration and Research

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the Johnson Sea Link II during sixteen dives of the "Bioluminescence 2009" expedition sponsored by the National Oceanic and...

  17. Submersible Data (Dive Trackpoints) for Operation Deep Scope 2007 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link II along its track during nineteen dives of the 2007 "Operation Deep Scope" expedition sponsored...

  18. Indirect impacts of recreational scuba diving: patterns of growth and predation in branching stony corals

    National Research Council Canada - National Science Library

    Guzner, Barak; Novplansky, Ariel; Shalit, Or; Chadwick, Nanette E

    2010-01-01

    .... We compared coral skeletal growth and damage at sites that were protected vs unprotected from diving tourism, and identified tissue mortality through monthly monitoring of the branching stony coral Acropora hemprichii (Ehrenberg, 1834...

  19. Buoyancy Regulation and the Energetics of Diving in Dolphins Seals, Sea Lions and Sea Otters

    National Research Council Canada - National Science Library

    Costa, Daniel

    1998-01-01

    We examined swim speed and ascent descent rates in sea lions and elephant seals in order to make comparisons in their diving strategies and how these may be effected by different strategies of buoyancy regulation...

  20. Submersible Data (Dive Waypoints) for Bioluminescence 2009 - Office of Ocean Exploration and Research

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link II at waypoints along its track during seventeen dives of the 2009 "Bioluminescence" expedition...

  1. Non-Dive Activities for Lophelia II 2009 - Office of Ocean Exploration and Research

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Non-dive activities reported to the NOAA Office of Ocean Exploration and Research for the "Lophelia II" expedition, Aug. 19 through Sept. 12, 2009. Information...

  2. Non-Dive Activities for Davidson Seamount 2006 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Non-dive activities reported to the NOAA Office of Ocean Exploration for the "Davidson Seamount" expedition, January 26 through February 5, 2006. Information...

  3. EX1504L3 Dive02 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L3: CAPSTONE Leg III:...

  4. EX1504L4 Dive11 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to Address...

  5. EX1504L2 Dive04 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  6. EX1504L2 Dive14 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  7. EX1504L3 Dive06 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L3: CAPSTONE Leg III:...

  8. EX1504L2 Dive01 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  9. EX1504L4 Dive05 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to Address...

  10. EX1504L4 Dive12 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to Address...

  11. EX1504L4 Dive01 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to Address...

  12. EX1504L2 Dive17 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  13. EX1504L2 Dive08 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  14. EX1504L2 Dive07 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  15. EX1504L2 Dive05 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  16. EX1504L4 Dive09 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to Address...

  17. EX1504L2 Dive11 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  18. EX1504L4 Dive08 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to Address...

  19. EX1504L2 Dive16 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  20. EX1504L2 Dive12 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  1. Satellite-linked locational, mapping, and diving of sea turtles in pelagic and coastal benthic habitats

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Satellite telemetry determines migratory pathways to the foraging and nesting areas, degree of fixation on a foraging area, diving behaviors during the migrations,...

  2. Bermuda Deep Water Caves 2011: Dives of Discovery between 20110607 and 20110627

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — During the three week NOAA Ocean Exploration project, Bermuda Deep Water Caves 2011: Dives of Discovery, our four member deep team, aided by numerous assistants,...

  3. Dive Activities for Expedition to the Deep Slope 2006 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Information about dive activities were recorded by personnel during the "Expedition to the Deep Slope 2006" expedition, May 7 through June 2, 2006. Additional...

  4. Dive Activities for Expedition to the Deep Slope 2007 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Information about dive activities were recorded by personnel during the "Expedition to the Deep Slope 2007" expedition, June 4 through July 6, 2007. Additional...

  5. Non-Dive Activities for Life on the Edge 2005 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Information about non-dive activities were recorded into the Cruise Information Management System (CIMS) by the NOAA Office of Ocean Exploration's data manager...

  6. Non-Dive Activities for Investigating the Charleston Bump 2003 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Information about non-dive activities were recorded into the Cruise Information Management System (CIMS) by the NOAA Office of Ocean Exploration's data manager...

  7. Growing Evidence about the Relationship between Vessel Dissection and Scuba Diving

    Directory of Open Access Journals (Sweden)

    Simona Brajkovic

    2013-09-01

    Full Text Available Carotid and vertebral artery dissection are relatively frequent and risky conditions. In the last decade, different patients with extracranial (and in 1 case also intracranial dissections associated with the practice of scuba diving were reported. The connection between the two conditions has not been fully explained so far. In the present article, we report the case of a patient presenting with Claude Bernard-Horner syndrome and homolateral XII cranial nerve palsy, manifesting a few days after diving in the cold water of a lake. The patient ended up having internal carotid artery dissection associated with the formation of a pseudoaneurysm. Here, we offer a summary of all cases reported in the literature about scuba diving and arterial dissection, and provide a critical discussion about which scuba diving-related factors can trigger the dissection of cervical vessels.

  8. EX1504L3 Dive05 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L3: CAPSTONE Leg III:...

  9. EX1606 Dive04 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1606: CAPSTONE Wake Island...

  10. EX1605L3 Dive19 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1605L3: CAPSTONE CNMI &...

  11. EX1504L4 Dive03 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to Address...

  12. EX1504L2 Dive02 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  13. EX1504L2 Dive06 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  14. EX1504L2 Dive18 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  15. EX1504L3 Dive03 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L3: CAPSTONE Leg III:...

  16. EX1504L3 Dive07 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L3: CAPSTONE Leg III:...

  17. EX1504L2 Dive09 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  18. EX1504L2 Dive15 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  19. Submersible Data (Dive Trackpoints) for Life on the Edge 2004 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link I along its track during twenty-five dives of the 2004 "Life on the Edge" expedition sponsored by...

  20. Non-Dive Activities for Life on the Edge 2004 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Information about non-dive activities were recorded into the Cruise Information Management System (CIMS) by the NOAA Office of Ocean Exploration's data manager...

  1. New records of predaceous diving beetles (Coleoptera:Dytiscidae) in Maine

    Science.gov (United States)

    Boobar, L.R.; Gibbs, K.E.; Longcore, J.R.; Perillo, A.M.

    1996-01-01

    Locations, habitat descriptions, and collection dates are listed for new records of 4 genera and 12 species of predaceous diving beetles (Coleoptera: Dytiscidae) in Maine. Previously, 17 genera and 53 species of the aquatic beetle were reported from Maine.

  2. EX1504L4 Dive04 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to Address...

  3. EX1504L4 Dive06 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to Address...

  4. EX1504L4 Dive10 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to Address...

  5. EX1504L4 Dive02 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to Address...

  6. Dive Activities for Bioluminescence 2009 - Office of Ocean Exploration and Research

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Information about dive activities were recorded by personnel during the "Bioluminescence 2009" expedition, July 20 through 31, 2009. Additional information was...

  7. The diving reflex in healthy infants in the first year of life.

    Science.gov (United States)

    Pedroso, Fleming S; Riesgo, Rudimar S; Gatiboni, Tanira; Rotta, Newra T

    2012-02-01

    A cohort study was conducted with a random sample of 33 healthy infants evaluated at birth and at 1, 2, 3, 4, 5, 6, 9, and 12 months to determine the frequency of respiratory rate changes in response to air blown over the face (diving reflex) in the first year of life, and to standardize the description of diving reflex occurrence. All 33 infants remained neurologically normal throughout follow-up. Diving reflex was observed in 95.3% of newborns and in 100% of infants between 2 and 6 months of age. At 6 months, it started to decrease but persisted in 90% of the infants up to 12 months. The diving reflex is highly prevalent in the first year of life and can be easily elicited by applying a flow of air over the infant's face, particularly during crying.

  8. Non-Dive Activities for Operation Deep Scope 2005 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Information about non-dive activities were recorded into the Cruise Information Management System (CIMS) by the NOAA Office of Ocean Exploration's data manager...

  9. EX1605L3 Dive17 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1605L3: CAPSTONE CNMI &...

  10. EX1605L3 Dive22 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1605L3: CAPSTONE CNMI &...

  11. Submersible Data (Dive Waypoints) for Life on the Edge 2005 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link I at waypoints along its track during nineteen dives of the 2005 "Life on the Edge" expedition...

  12. Submersible Data (Dive Waypoints) for Investigating the Charleston Bump 2003 - Office of Ocean Exploration

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the submersible Johnson Sea-Link II at waypoints along its track during fourteen dives of the 2003 "Investigating the Charleston...

  13. Submersible Data (Dive Trackpoints) for Lophelia II 2008 - Office of Ocean Exploration and Research

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by the Remotely Operated Vehicle SeaEye Falcon along its track during four dives of the "Lophelia II 2008" expedition sponsored by the...

  14. EX1504L3 Dive04 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L3: CAPSTONE Leg III:...

  15. Submersible Data (Dive Trackpoints) for Bonaire 2008 - Office of Ocean Exploration and Research

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Data and information collected by Gavia AUVs along tracks during dives of the "Bonaire 2008" expedition sponsored by the National Oceanic and Atmospheric...

  16. Dive Activities for Bonaire 2008 - Office of Ocean Exploration and Research

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Information about dive activities were recorded by personnel during the "Bonaire 2008" expedition, January 7 through 30, 2008. Additional information was documented...

  17. Dive Behavior of Eastern Chukchi Beluga Whales (Delphinapterus leucas), 1998—2008

    National Research Council Canada - National Science Library

    JOHN J. CITTA; ROBERT S. SUYDAM; LORI T. QUAKENBUSH; KATHRYN J. FROST; GREGORY M. O'CORRY-CROWE

    2013-01-01

    We provide an exploratory description of the dive behavior of 23 beluga whales of the eastern Chukchi Sea stock, tagged with satellite-linked time and depth recorders at Point Lay, Alaska, between 1998 and 2007...

  18. EX1504L2 Dive03 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  19. EX1504L2 Dive10 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  20. EX1504L2 Dive13 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L2: Campaign to Address...

  1. EX1504L4 Dive07 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to Address...

  2. EX1605L3 Dive11 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1605L3: CAPSTONE CNMI &...

  3. EX1606 Dive03 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1606: CAPSTONE Wake Island...

  4. EX1605L3 Dive09 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1605L3: CAPSTONE CNMI &...

  5. EX1605L3 Dive02 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1605L3: CAPSTONE CNMI &...

  6. EX1606 Dive08 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1606: CAPSTONE Wake Island...

  7. EX1606 Dive13 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1606: CAPSTONE Wake Island...

  8. EX1605L3 Dive01 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1605L3: CAPSTONE CNMI &...

  9. EX1605L3 Dive16 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1605L3: CAPSTONE CNMI &...

  10. EX1606 Dive10 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1606: CAPSTONE Wake Island...

  11. EX1606 Dive05 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1606: CAPSTONE Wake Island...

  12. EX1606 Dive06 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1606: CAPSTONE Wake Island...

  13. EX1605L3 Dive10 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1605L3: CAPSTONE CNMI &...

  14. EX1605L3 Dive20 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1605L3: CAPSTONE CNMI &...

  15. EX1504L4 Dive13 Ancillary Data Collection including reports, kmls, spreadsheets, images and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1504L4: Campaign to Address...

  16. EX1605L3 Dive21 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1605L3: CAPSTONE CNMI &...

  17. EX1606 Dive01 Ancillary Data Collection including reports, kmls, spreadsheets, and data

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Standard suite of ancillary data files generated through a scripting process following an ROV dive on NOAA Ship Okeanos Explorer during EX1606: CAPSTONE Wake Island...

  18. Winter and spring diving behavior of bowhead whales relative to prey

    KAUST Repository

    Heide-Jørgensen, Mads

    2013-10-23

    Background Little is known about bowhead whale (Balaena mysticetus) foraging behavior and what concentrations of prey are required to balance the energetic trade-offs of feeding. We used satellite telemetry, archival depth recorders, and water column echo sounding data to study bowhead whale diving behavior relative to prey depth and concentration in Disko Bay, West Greenland. Results Between March and May 2008 to 2011, nine bowhead whales were tagged in Disko Bay, West Greenland with instruments that collected data on location and diving over a period of 1 to 33 days. The frequency of U-dives (presumed to be foraging dives) was low during winter months but more than doubled in spring concurrent with a decrease in diving depth. The mean speed of the horizontal bottom phase of the U-dives was 0.9 ms-1 and on average, whales spent 37% of their time at the bottom phase of the dive. In March, bowhead whales presumably fed on copepods (Calanus spp.) close to the seabed (between 100 and 400 m). In April and May, after the copepods ascended to shallower depths, bowhead whales also dove to shallower depths (approximately 30 m) more often. However, echo sounding surveys in the vicinity of feeding whales in early May indicated that patches of copepods could still be found close to the seabed. Conclusions There was a marked change in diving behavior from winter through spring and this was likely in response to the changes in sea ice conditions, primary production and potential copepod abundance in the upper part of the water column. Depth and duration of dives changed significantly during this period; however, other dive parameters (for example the proportion of time spent feeding on the bottom of U-dives) remained fairly constant indicating a constant feeding effort. Bowhead whales target copepods at or close to the seabed in winter months in Disko Bay and continue feeding on copepods when they migrate to the surface. However, bowhead whales leave West Greenland before peak

  19. Specialist advice may improve patient selection for decompression therapy following diving accidents: a retrospective observational study.

    Science.gov (United States)

    Steffensmeier, Daniel; Albrecht, Roland; Wendling, Jürg; Melliger, Roger; Spahn, Donat R; Stein, Philipp; Wyss, Christophe

    2017-10-19

    Even in a landlocked country like Switzerland recreational diving is becoming more and more popular. Smaller lakes in the Alps are located at an altitude of 2500 m above sea level. The incidence of diving accidents among all helicopter emergency service missions and the consecutive medical knowledge about decompression injuries is low. Thus, a collaboration between the Swiss Air-Ambulance (Rega) and the divers alert network (DAN) was initiated to improve patient treatment and identification of decompression injury and necessity of hyperbaric oxygen therapy (HBO). Retrospective observational study that includes all patients treated by the Rega which have been classified to have had a diving accident from 2005 to 2014. Patient and diving epidemiology was assessed and the impact of DAN collaboration on patient selection and identification of patients needing transport to HBO facilities were analysed. In the 10-year observational period 116 patients with diving accidents were treated by Rega. Mean patient age was 40 (SD 11) years and 95 (82%) were male. If the Rega emergency physician suspected a decompression injury (DCI), without DAN contact 27/28 (96%) of these patients were transported directly to a HBO facility, whereas with DAN contact only 53/63 (84%) needed transport to a HBO facility. DAN was involved in 66/96 (69%) of the cases with suspected DCI on scene, with a significant increase over time (p = 0.001). Mean flight time to HBO facilities was significantly longer (28.9, SD 17.7 min.), compared to non-HBO facilities (7.1, SD 3.2 min., p therapy can be provided by HEMS within less than 30 min all over Switzerland. For diving accidents among HEMS missions, specialist advice by diving medicine specialists (DAN) appears mandatory to accurately identify and transport patients with decompression injury, as exposure of emergency physicians towards diving accidents and the diagnosis of DCI is low.

  20. Specialist advice may improve patient selection for decompression therapy following diving accidents: a retrospective observational study

    OpenAIRE

    Steffensmeier, Daniel; Albrecht, Roland; Wendling, Jürg; Melliger, Roger; Spahn, Donat R.; Stein, Philipp; Wyss, Christophe

    2017-01-01

    Background Even in a landlocked country like Switzerland recreational diving is becoming more and more popular. Smaller lakes in the Alps are located at an altitude of 2500 m above sea level. The incidence of diving accidents among all helicopter emergency service missions and the consecutive medical knowledge about decompression injuries is low. Thus, a collaboration between the Swiss Air-Ambulance (Rega) and the divers alert network (DAN) was initiated to improve patient treatment and ident...

  1. A Review of SCUBA Diving Impacts and Implication for Coral Reefs Conservation and Tourism Management

    OpenAIRE

    Zainal Abidin Siti Zulaiha; Mohamed Badaruddin

    2014-01-01

    Dive tourism has become important in term of magnitude and significantly contributes to regional economies. Nevertheless, in the absence of proper controls and enforcement, unplanned tourism growth has caused environmental degradation which undermines the long-term sustainability of the tourism industry. The purpose of this paper is to explore factors that contribute to the SCUBA diving impacts on coral and fish communities. This paper explains the causes of a certain event, validating the pr...

  2. Can Foraging Ecology Drive the Evolution of Body Size in a Diving Endotherm?

    Science.gov (United States)

    Cook, Timothée R.; Lescroël, Amélie; Cherel, Yves; Kato, Akiko; Bost, Charles-André

    2013-01-01

    Within a single animal species, different morphs can allow for differential exploitation of foraging niches between populations, while sexual size dimorphism can provide each sex with access to different resources. Despite being potentially important agents of evolution, resource polymorphisms, and the way they operate in wild populations, remain poorly understood. In this study, we examine how trophic factors can select for different body sizes between populations and sexes in a diving endotherm. Dive depth and duration are positively related to body size in diving birds and mammals, a relationship explained by a lower mass-specific metabolic rate and greater oxygen stores in larger individuals. Based on this allometry, we predict that selection for exploiting resources situated at different depths can drive the evolution of body size in species of diving endotherms at the population and sexual level. To test this prediction, we studied the foraging ecology of Blue-eyed Shags, a group of cormorants with male-biased sexual size dimorphism from across the Southern Ocean. We found that mean body mass and relative difference in body mass between sexes varied by up to 77% and 107% between neighbouring colonies, respectively. Birds from colonies with larger individuals dived deeper than birds from colonies with smaller individuals, when accounting for sex. In parallel, males dived further offshore and deeper than females and the sexual difference in dive depth reflected the level of sexual size dimorphism at each colony. We argue that body size in this group of birds is under intense selection for diving to depths of profitable benthic prey patches and that, locally, sexual niche divergence selection can exaggerate the sexual size dimorphism of Blue-eyed Shags initially set up by sexual selection. Our findings suggest that trophic resources can select for important geographic micro-variability in body size between populations and sexes. PMID:23409169

  3. Design of an adaptive controller for dive-plane control of a torpedo-shaped AUV

    Science.gov (United States)

    Cao, Jian; Su, Yumin; Zhao, Jinxin

    2011-09-01

    Underwater vehicles operating in complex ocean conditions present difficulties in determining accurate dynamic models. To guarantee robustness against parameter uncertainty, an adaptive controller for dive-plane control, based on Lyapunov theory and back-stepping techniques, was proposed. In the closed-loop system, asymptotic tracking of the reference depth and pitch angle trajectories was accomplished. Simulation results were presented which show effective dive-plane control in spite of the uncertainties in the system parameters.

  4. How man-made interference might cause gas bubble emboli in deep diving whales

    OpenAIRE

    Andreas eFahlman; Tyack, Peter L; Patrick James Miller; Kvadsheim, Petter H.

    2014-01-01

    Recent cetacean mass strandings in close temporal and spatial association with sonar activity has raised the concern that anthropogenic sound may harm breath-hold diving marine mammals. Necropsy results of the stranded whales have shown evidence of bubbles in the tissues, similar to those in human divers suffering from decompression sickness (DCS). It has been proposed that changes in behavior or physiological responses during diving could increase tissue and blood N2 levels, thereby increasi...

  5. The political economy of dive tourism: precarity at the periphery in Malaysia

    OpenAIRE

    Hampton, Mark P.; Jeyacheya, Julia; Lee, Donna

    2017-01-01

    Using a critical political economy approach and the concept of labour precarity, the international dive tourism industry in Sabah, Malaysia and its workers’ vulnerabilities are interrogated. Fieldwork data highlights dive tourism’s socio-economic impacts and the precarity of labour within the international tourism sector and also critiques it as a development strategy for a peripheral region. The paper challenges the optimistic views of labour precarity found in the existing political economy...

  6. Predaceous diving beetles in Maine: Faunal list and keys to subfamilies

    Science.gov (United States)

    Boobar, L.R.; Spangler, P.J.; Gibbs, K.E.; Longcore, J.R.; Hopkins, K.M.

    1998-01-01

    Records of predaceous diving beetles (Coleoptera: Dytiscidae) collected in Maine are summarized. These records are augmented by field surveys of beetles in Aroostook Co., Maine during 1993-95. Keys to subfamilies are presented with color plates for selected species. A list of diving beetles that have been collected near Maine (state or province) is presented so that investigators will know what additional species might be expected in Maine. Basic taxonomy is presented to facilitate use of keys.

  7. Can foraging ecology drive the evolution of body size in a diving endotherm?

    Directory of Open Access Journals (Sweden)

    Timothée R Cook

    Full Text Available Within a single animal species, different morphs can allow for differential exploitation of foraging niches between populations, while sexual size dimorphism can provide each sex with access to different resources. Despite being potentially important agents of evolution, resource polymorphisms, and the way they operate in wild populations, remain poorly understood. In this study, we examine how trophic factors can select for different body sizes between populations and sexes in a diving endotherm. Dive depth and duration are positively related to body size in diving birds and mammals, a relationship explained by a lower mass-specific metabolic rate and greater oxygen stores in larger individuals. Based on this allometry, we predict that selection for exploiting resources situated at different depths can drive the evolution of body size in species of diving endotherms at the population and sexual level. To test this prediction, we studied the foraging ecology of Blue-eyed Shags, a group of cormorants with male-biased sexual size dimorphism from across the Southern Ocean. We found that mean body mass and relative difference in body mass between sexes varied by up to 77% and 107% between neighbouring colonies, respectively. Birds from colonies with larger individuals dived deeper than birds from colonies with smaller individuals, when accounting for sex. In parallel, males dived further offshore and deeper than females and the sexual difference in dive depth reflected the level of sexual size dimorphism at each colony. We argue that body size in this group of birds is under intense selection for diving to depths of profitable benthic prey patches and that, locally, sexual niche divergence selection can exaggerate the sexual size dimorphism of Blue-eyed Shags initially set up by sexual selection. Our findings suggest that trophic resources can select for important geographic micro-variability in body size between populations and sexes.

  8. Temporomandibular disorders in scuba divers-an increased risk during diving certification training.

    Science.gov (United States)

    Oztürk, Ozmen; Tek, Mustafa; Seven, Hüseyin

    2012-11-01

    The design of a diving regulator's mouthpiece increases the risk of a temporomandibular disorder (TMD) in scuba divers. The total weight of a diving regulator is reflected directly on the temporomandibular joint, causing articular and periarticular disorders. In the current study, the prevalence of TMD in scuba divers triggered during diving certification training is investigated. We also aimed to determine the factors that lead to TMD during diving training and clarify the observation that there is an increased incidence of TMD in inexperienced divers. The study was held between 2006 and 2011. Ninety-seven divers were referred with the complaint of pain around temporomandibular area. The divers were classified according to their diving experience. Symptoms and signs of TMD were graded. Fourteen divers were diagnosed with TMD. Temporomandibular disorder was seen more frequently in inexperienced divers than in experienced divers (P = 0.0434). The most prevalent symptom was an increased effort for mouthpiece gripping. Temporomandibular joint tenderness and trigger point activation were the mostly seen physical signs. Thirteen divers had an improvement with therapy. The increased effort for stabilizing the mouthpiece is a recognized factor in TMD development. Attention must be paid to an association of scuba diving with TMDs, especially in inexperienced divers having a scuba certification training.

  9. Hemoptysis due to breath-hold diving following chemotherapy and lung irradiation.

    Science.gov (United States)

    Gutsche, Markus; Kuschner, Ware G

    2012-08-01

    Breath-hold diving, also known as free-diving, describes the practice of intentional immersion under water without an external supply of oxygen. Pulmonary hemorrhage with hemoptysis has been reported as a complication of immersion and breath-hold diving in young healthy athletes. We report the case of a 60-year-old man with a history of radiation and chemotherapy for breast carcinoma, who developed the abrupt onset of hemoptysis in the setting of swimming and breath-hold diving. A computed tomography (CT) scan of the chest demonstrated an area of ground glass opacification, suggestive of pulmonary hemorrhage, superimposed on a background of reticular opacities within the prior radiation field. A follow-up CT scan of the chest, obtained 2 months after presentation, demonstrated resolution of the ground glass opacification, but persistence of fibrotic features attributable to prior radiation therapy. We postulate that prior irradiation of the chest resulted in lung injury and fibrosis which, in turn, rendered the affected region of the lung susceptible to "stress failure," due to an increase in the transcapillary pressure gradient arising from immersion and breath-hold diving. Patients with a history of lung injury resulting from chest irradiation should be cautioned about pulmonary hemorrhage and hemoptysis as a potential complication of swimming and breath-hold diving.

  10. Provisional report on diving-related fatalities in Australian waters 2009.

    Science.gov (United States)

    Lippmann, John; Lawrence, Chris; Fock, Andrew; Wodak, Thomas; Jamieson, Scott

    2013-12-01

    An individual case review of diving-related deaths reported as occurring in Australia in 2009 was conducted as part of the DAN Asia-Pacific Dive Fatality Reporting Project. The case studies were compiled using reports from witnesses, the police and coroners. In each case, the particular circumstances of the accident and details from the post-mortem examination, where available, are provided. In total, there were 21 reported fatalities (two more than in 2008), including 18 males and three females. Twelve deaths occurred while snorkelling and/or breath-hold diving, eight while scuba diving and one while using surface-supply breathing apparatus. Apneic hypoxia continues to be a problem with breath-hold divers and appears to have caused the death of three victims in this series. Cardiac-related issues were thought to have been the disabling injury in the deaths of at least three snorkel divers and at least three scuba divers. One of the victims was a student who became separated from her instructor on an introductory scuba dive in poor visibility. Apneic hypoxia, pre-existing medical conditions, snorkelling or diving alone, separation and inadequate supervision were once again features in several deaths in this series.

  11. Cervical spine injuries from diving accident: a 10-year retrospective descriptive study on 64 patients.

    Science.gov (United States)

    Chan-Seng, E; Perrin, F E; Segnarbieux, F; Lonjon, N

    2013-09-01

    Ninety percent of the lesions resulting from diving injuries affect the cervical spine and are potentially associated with spinal cord injuries. The objective is to determine the most frequent lesion mechanisms. Evaluate the therapeutic alternatives and the biomechanical evolution (kyphotic deformation) of diving-induced cervical spine injuries. Define epidemiological characteristics of diving injuries. A retrospective analysis over a period of 10 years was undertaken for patients admitted to the Department of Neurosurgery of Montpellier, France, with cervical spinal injuries due to a diving accident. Patients were re-evaluated and clinical and radiological evaluation follow-ups were done. This study included 64 patients. Cervical spine injuries resulting from diving predominantly affect young male subjects. They represent 9.5% of all the cervical spine injuries. In 22% of cases, patients presented severe neurological troubles (ASIA A, B, C) at the time of admission. A surgical treatment was done in 85% of cases, mostly using an anterior cervical approach. This is a retrospective study (type IV) with some limitations. The incidence of diving injuries in our region is one of the highest as compared to reports in the literature. Despite an increase of our surgical indications, 55% of these cases end up with a residual kyphotic deformation but there is no relationship between the severity of late vertebral deformity and high Neck Pain and Disability Scale (NPDS) scores. Level IV, retrospective study. Copyright © 2013 Elsevier Masson SAS. All rights reserved.

  12. Ecological carrying capacity assessment of diving site: A case study of Mabul Island, Malaysia.

    Science.gov (United States)

    Zhang, Li-Ye; Chung, Shan-Shan; Qiu, Jian-Wen

    2016-12-01

    Despite considered a non-consumptive use of the marine environment, diving-related activities can cause damages to coral reefs. It is imminent to assess the maximum numbers of divers that can be accommodated by a diving site before it is subject to irreversible deterioration. This study aimed to assess the ecological carrying capacity of a diving site in Mabul Island, Malaysia. Photo-quadrat line transect method was used in the benthic survey. The ecological carrying capacity was assessed based on the relationship between the number of divers and the proportion of diver damaged hard corals in Mabul Island. The results indicated that the proportion of diver damaged hard corals occurred exponentially with increasing use. The ecological carrying capacity of Mabul Island is 15,600-16,800 divers per diving site per year at current levels of diver education and training with a quarterly threshold of 3900-4200 per site. Our calculation shows that management intervention (e.g. limiting diving) is justified at 8-14% of hard coral damage. In addition, the use of coral reef dominated diving sites should be managed according to their sensitivity to diver damage and the depth of the reefs. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Presumed Arterial Gas Embolism After Breath-Hold Diving in Shallow Water.

    Science.gov (United States)

    Harmsen, Stefani; Schramm, Dirk; Karenfort, Michael; Christaras, Andreas; Euler, Michael; Mayatepek, Ertan; Tibussek, Daniel

    2015-09-01

    Dive-related injuries are relatively common, but almost exclusively occur in recreational or scuba diving. We report 2 children with acute central nervous system complications after breath-hold diving. A 12-year-old boy presented with unilateral leg weakness and paresthesia after diving beneath the water surface for a distance of ∼25 m. After ascent, he suddenly felt extreme thoracic pain that resolved spontaneously. Neurologic examination revealed right leg weakness and sensory deficits with a sensory level at T5. Spinal MRI revealed a nonenhancing T2-hyperintense lesion in the central cord at the level of T1/T2 suggesting a spinal cord edema. A few weeks later, a 13-year-old girl was admitted with acute dizziness, personality changes, confusion, and headache. Thirty minutes before, she had practiced diving beneath the water surface for a distance of ∼25 m. After stepping out, she felt sudden severe thoracic pain and lost consciousness. Shortly later she reported headache and vertigo, and numbness of the complete left side of her body. Neurologic examination revealed reduced sensibility to all modalities, a positive Romberg test, and vertigo. Cerebral MRI revealed no pathologic findings. Both children experienced a strikingly similar clinical course. The chronology of events strongly suggests that both patients were suffering from arterial gas embolism. This condition has been reported for the first time to occur in children after breath-hold diving beneath the water surface without glossopharyngeal insufflation. Copyright © 2015 by the American Academy of Pediatrics.

  14. Using stimulation of the diving reflex in humans to teach integrative physiology.

    Science.gov (United States)

    Choate, Julia K; Denton, Kate M; Evans, Roger G; Hodgson, Yvonne

    2014-12-01

    During underwater submersion, the body responds by conserving O2 and prioritizing blood flow to the brain and heart. These physiological adjustments, which involve the nervous, cardiovascular, and respiratory systems, are known as the diving response and provide an ideal example of integrative physiology. The diving reflex can be stimulated in the practical laboratory setting using breath holding and facial immersion in water. Our undergraduate physiology students complete a laboratory class in which they investigate the effects of stimulating the diving reflex on cardiovascular variables, which are recorded and calculated with a Finapres finger cuff. These variables include heart rate, cardiac output, stroke volume, total peripheral resistance, and arterial pressures (mean, diastolic, and systolic). Components of the diving reflex are stimulated by 1) facial immersion in cold water (15°C), 2) breathing with a snorkel in cold water (15°C), 3) facial immersion in warm water (30°C), and 4) breath holding in air. Statistical analysis of the data generated for each of these four maneuvers allows the students to consider the factors that contribute to the diving response, such as the temperature of the water and the location of the sensory receptors that initiate the response. In addition to providing specific details about the equipment, protocols, and learning outcomes, this report describes how we assess this practical exercise and summarizes some common student misunderstandings of the essential physiological concepts underlying the diving response. Copyright © 2014 The American Physiological Society.

  15. Blood platelet count and bubble formation after a dive to 30 msw for 30 min.

    Science.gov (United States)

    Pontier, Jean-Michel; Jimenez, Chantal; Blatteau, Jean-Eric

    2008-12-01

    Previous human studies reported that platelet count (PC) is decreased following decompression. Platelet aggregation and adherence to the bubble surface has been demonstrated in severe decompression sickness (DCS). The present study was designed to clarify the relationship between post-dive changes in blood PC and the level of bubble formation in divers. There were 40 healthy experienced divers who were assigned to 1 experimental group (N = 30) with an open-sea air dive to 30 msw for 30 min in field conditions and 1 control group (N = 10) without hyperbaric exposure. Bubble grades were monitored with a pulsed Doppler according to the Spencer scale and Kissman integrated severity score (KISS). Blood samples for red blood cell counts (RBC), hematocrit (Hct), and PC were taken 1 h before and after exposure in two groups. None of the divers developed any signs of DCS. In two groups, the results showed significant increase in RBC count and Hct related with hemoconcentration and no change in PC. Divers with a high KISS score (39 +/- 5.8; mean +/- SD) presented a significantly more pronounced percent fall in PC than divers with a lower KISS score. We found a significant correlation between the percent fall in PC after a dive and the bubble KISS score. The present study highlighted a relationship between the post-dive decrease in PC and the magnitude of bubble level after decompression. Our primary result is that the post-dive decrease in PC could be a predictor of decompression severity after diving.

  16. Physiological, morphological, and ecological tradeoffs influence vertical habitat use of deep-diving toothed-whales in the Bahamas.

    Science.gov (United States)

    Joyce, Trevor W; Durban, John W; Claridge, Diane E; Dunn, Charlotte A; Fearnbach, Holly; Parsons, Kim M; Andrews, Russel D; Ballance, Lisa T

    2017-01-01

    Dive capacity among toothed whales (suborder: Odontoceti) has been shown to generally increase with body mass in a relationship closely linked to the allometric scaling of metabolic rates. However, two odontocete species tagged in this study, the Blainville's beaked whale Mesoplodon densirostris and the Cuvier's beaked whale Ziphius cavirostris, confounded expectations of a simple allometric relationship, with exceptionally long (mean: 46.1 min & 65.4 min) and deep dives (mean: 1129 m & 1179 m), and comparatively small body masses (med.: 842.9 kg & 1556.7 kg). These two species also exhibited exceptionally long recovery periods between successive deep dives, or inter-deep-dive intervals (M. densirostris: med. 62 min; Z. cavirostris: med. 68 min). We examined competing hypotheses to explain observed patterns of vertical habitat use based on body mass, oxygen binding protein concentrations, and inter-deep-dive intervals in an assemblage of five sympatric toothed whales species in the Bahamas. Hypotheses were evaluated using dive data from satellite tags attached to the two beaked whales (M. densirostris, n = 12; Z. cavirostris, n = 7), as well as melon-headed whales Peponocephala electra (n = 13), short-finned pilot whales Globicephala macrorhynchus (n = 15), and sperm whales Physeter macrocephalus (n = 27). Body mass and myoglobin concentration together explained only 36% of the variance in maximum dive durations. The inclusion of inter-deep-dive intervals, substantially improved model fits (R2 = 0.92). This finding supported a hypothesis that beaked whales extend foraging dives by exceeding aerobic dive limits, with the extension of inter-deep-dive intervals corresponding to metabolism of accumulated lactic acid. This inference points to intriguing tradeoffs between body size, access to prey in different depth strata, and time allocation within dive cycles. These tradeoffs and resulting differences in habitat use have important implications for spatial distribution

  17. How Elephant Seals (Mirounga leonina Adjust Their Fine Scale Horizontal Movement and Diving Behaviour in Relation to Prey Encounter Rate.

    Directory of Open Access Journals (Sweden)

    Yves Le Bras

    Full Text Available Understanding the diving behaviour of diving predators in relation to concomitant prey distribution could have major practical applications in conservation biology by allowing the assessment of how changes in fine scale prey distribution impact foraging efficiency and ultimately population dynamics. The southern elephant seal (Mirounga leonina, hereafter SES, the largest phocid, is a major predator of the southern ocean feeding on myctophids and cephalopods. Because of its large size it can carry bio-loggers with minimal disturbance. Moreover, it has great diving abilities and a wide foraging habitat. Thus, the SES is a well suited model species to study predator diving behaviour and the distribution of ecologically important prey species in the Southern Ocean. In this study, we examined how SESs adjust their diving behaviour and horizontal movements in response to fine scale prey encounter densities using high resolution accelerometers, magnetometers, pressure sensors and GPS loggers. When high prey encounter rates were encountered, animals responded by (1 diving and returning to the surface with steeper angles, reducing the duration of transit dive phases (thus improving dive efficiency, and (2 exhibiting more horizontally and vertically sinuous bottom phases. In these cases, the distance travelled horizontally at the surface was reduced. This behaviour is likely to counteract horizontal displacement from water currents, as they try to remain within favourable prey patches. The prey encounter rate at the bottom of dives decreased with increasing diving depth, suggesting a combined effect of decreased accessibility and prey density with increasing depth. Prey encounter rate also decreased when the bottom phases of dives were spread across larger vertical extents of the water column. This result suggests that the vertical aggregation of prey can regulate prey density, and as a consequence impact the foraging success of SESs. To our knowledge

  18. The minimum air volume kept in diving Adelie penguins : evidence for regulation of air volume in the respiratory system

    OpenAIRE

    Sato, Katsufumi; Watanuki, Yutaka; Naito, Yasuhiko

    2006-01-01

    Penguins are outstanding divers. Particularly intriguing is the observation that they seem to dive on inspiration, which contributes to increasing oxygen stores but which increases their buoyancy. It has been concluded that buoyancy is a major factor in determining the energetics of shallow diving birds and there is a positive correlation between estimated air volume in the body (respiratory system and feathers) and the maximum depth in the dive of free-ranging penguins. However, it is not kn...

  19. The Effect of a Diving Mask on Intraocular Pressure in a Healthy Population

    Directory of Open Access Journals (Sweden)

    Catherina Josephine Goenadi

    2016-06-01

    Full Text Available Purpose: Swimming goggles increase the intraocular pressure (IOP via the periorbital frame pressure and suction effect. In comparison, diving masks have a larger frame rim and incorporate the nose. The exact effect(s of diving masks on IOP is unknown. This study evaluates the influence of diving masks on IOP in normal, healthy subjects. Methods: Tonometry was performed in both eyes of all subjects with an AVIA®Tono-Pen by a single investigator. Measurements were taken at baseline without the diving mask and with the subjects wearing a small-volume, double-window diving mask, but with the mask lenses removed. Two IOP readings in each eye were measured, and an additional reading was measured if the difference between the initial 2 was ≥2 mm Hg. Central corneal thickness (CCT was also measured in each eye, using a contact pachymeter (OcuScan®Alcon. Results: Forty eyes of 20 healthy volunteers (age 29.7 ± 9.3 years; range 21–52 were included. The mean CCT was 544.4 ± 43.5 µm. The mean IOP before the diving mask was worn had been 17.23 ± 2.18 mm Hg (n = 40. The IOP decreased by 0.43 mm Hg (p < 0.05 to 16.80 ± 2.57 mm Hg after the diving mask had been put on. There was no correlation between IOP change and age (r = 0.143, p = 0.337, gender (r = –0.174, p = 0.283 or CCT (r = –0.123, p = 0.445. Conclusion: There was no increase in IOP after the diving mask had been worn. A small but statistically significant decrease in IOP was observed. This study demonstrates that unlike swimming goggles, the strap tension and frame pressure on the periorbital tissue from a diving mask does not increase IOP. Diving masks may be a suitable alternative to swimming goggles for patients with advanced glaucoma or glaucoma filtration surgery.

  20. The Effect of a Diving Mask on Intraocular Pressure in a Healthy Population.

    Science.gov (United States)

    Goenadi, Catherina Josephine; Law, David Zhiwei; Lee, Jia Wen; Ong, Ee Lin; Chee, Wai Kitt; Cheng, Jason

    2016-01-01

    Swimming goggles increase the intraocular pressure (IOP) via the periorbital frame pressure and suction effect. In comparison, diving masks have a larger frame rim and incorporate the nose. The exact effect(s) of diving masks on IOP is unknown. This study evaluates the influence of diving masks on IOP in normal, healthy subjects. Tonometry was performed in both eyes of all subjects with an AVIA(®)Tono-Pen by a single investigator. Measurements were taken at baseline without the diving mask and with the subjects wearing a small-volume, double-window diving mask, but with the mask lenses removed. Two IOP readings in each eye were measured, and an additional reading was measured if the difference between the initial 2 was ≥2 mm Hg. Central corneal thickness (CCT) was also measured in each eye, using a contact pachymeter (OcuScan(®)Alcon). Forty eyes of 20 healthy volunteers (age 29.7 ± 9.3 years; range 21-52) were included. The mean CCT was 544.4 ± 43.5 µm. The mean IOP before the diving mask was worn had been 17.23 ± 2.18 mm Hg (n = 40). The IOP decreased by 0.43 mm Hg (p $1003c; 0.05) to 16.80 ± 2.57 mm Hg after the diving mask had been put on. There was no correlation between IOP change and age (r = 0.143, p = 0.337), gender (r = -0.174, p = 0.283) or CCT (r = -0.123, p = 0.445). There was no increase in IOP after the diving mask had been worn. A small but statistically significant decrease in IOP was observed. This study demonstrates that unlike swimming goggles, the strap tension and frame pressure on the periorbital tissue from a diving mask does not increase IOP. Diving masks may be a suitable alternative to swimming goggles for patients with advanced glaucoma or glaucoma filtration surgery.

  1. 78 FR 11728 - Pilot Project on NAFTA Trucking Provisions

    Science.gov (United States)

    2013-02-19

    ... border commercial zones as detailed in the Agency's April 13, 2011, Federal Register notice . The pilot... Federal Motor Carrier Safety Administration Pilot Project on NAFTA Trucking Provisions AGENCY: Federal... applied to participate in the Agency's long-haul pilot program. That action was required by the ``U.S...

  2. Security framework for virtualised infrastructure services provisioned on-demand

    NARCIS (Netherlands)

    Ngo, C.; Membrey, P.; Demchenko, Y.; de Laat, C.

    2011-01-01

    Cloud computing is developing as a new wave of ICT technologies, offering a common approach to on-demand provisioning computation, storage and network resources which are generally referred to as infrastructure services. Most of currently available commercial Cloud services are built and organized

  3. 45 CFR Appendix A to Part 74 - Contract Provisions

    Science.gov (United States)

    2010-10-01

    ... 45 Public Welfare 1 2010-10-01 2010-10-01 false Contract Provisions A Appendix A to Part 74 Public Welfare DEPARTMENT OF HEALTH AND HUMAN SERVICES GENERAL ADMINISTRATION UNIFORM ADMINISTRATIVE REQUIREMENTS FOR AWARDS AND SUBAWARDS TO INSTITUTIONS OF HIGHER EDUCATION, HOSPITALS, OTHER NONPROFIT ORGANIZATIONS, AND COMMERCIAL ORGANIZATIONS Pt. 74,...

  4. Seagrass Importance in Food Provisioning Services: Fish Stomach ...

    African Journals Online (AJOL)

    2008-05-21

    May 21, 2008 ... Abstract—The links between ecosystem processes and functions and ecosystem services (i.e. the human benefits from those) are elusive. In this paper, the food provisioning service of seagrass meadows is operationalized through the study of the stomach contents of 13 important commercial fish species ...

  5. Experimental Studies and Dynamics Modeling Analysis of the Swimming and Diving of Whirligig Beetles (Coleoptera: Gyrinidae)

    Science.gov (United States)

    Jia, Xinghua; Zhang, Mingjun

    2012-01-01

    Whirligig beetles (Coleoptera, Gyrinidae) can fly through the air, swiftly swim on the surface of water, and quickly dive across the air-water interface. The propulsive efficiency of the species is believed to be one of the highest measured for a thrust generating apparatus within the animal kingdom. The goals of this research were to understand the distinctive biological mechanisms that allow the beetles to swim and dive, while searching for potential bio-inspired robotics applications. Through static and dynamic measurements obtained using a combination of microscopy and high-speed imaging, parameters associated with the morphology and beating kinematics of the whirligig beetle's legs in swimming and diving were obtained. Using data obtained from these experiments, dynamics models of both swimming and diving were developed. Through analysis of simulations conducted using these models it was possible to determine several key principles associated with the swimming and diving processes. First, we determined that curved swimming trajectories were more energy efficient than linear trajectories, which explains why they are more often observed in nature. Second, we concluded that the hind legs were able to propel the beetle farther than the middle legs, and also that the hind legs were able to generate a larger angular velocity than the middle legs. However, analysis of circular swimming trajectories showed that the middle legs were important in maintaining stable trajectories, and thus were necessary for steering. Finally, we discovered that in order for the beetle to transition from swimming to diving, the legs must change the plane in which they beat, which provides the force required to alter the tilt angle of the body necessary to break the surface tension of water. We have further examined how the principles learned from this study may be applied to the design of bio-inspired swimming/diving robots. PMID:23209398

  6. CNS oxygen toxicity in closed-circuit diving: signs and symptoms before loss of consciousness.

    Science.gov (United States)

    Arieli, R; Arieli, Y; Daskalovic, Y; Eynan, M; Abramovich, A

    2006-11-01

    There is a dearth of information regarding CNS oxygen toxicity accidents in closed-circuit oxygen diving. The aims of the present study were to report the sensations and symptoms that accompany CNS oxygen toxicity accidents, and to evaluate whether loss of consciousness can occur without any warning signs. We documented 36 CNS oxygen toxicity accidents in closed-circuit oxygen diving. The full accident inquiry included the first report from the diving unit, an interview of the victim and his buddy by the researchers, and an examination of the diving equipment. The symptoms that appeared before termination of a dive, as reported by the victim or his buddy, were as follows (in descending order of frequency): limb convulsions; hyperventilation; difficulty maintaining a steady depth; headache; and visual disturbances. The symptoms that appeared after detachment from the mouthpiece were, in descending order of frequency: headache; loss of consciousness; confusion; weakness; dizziness; and facial muscle twitching and limb convulsions. A high inspired CO2 [mean 4.2 kPa (29.9 mmHg)] was connected with loss of consciousness. No dive was terminated before at least two symptoms (mean 3.4) had been noted a minimum of 5 min before termination. Symptoms that are accepted as being related to CNS oxygen toxicity, as well as others such as headache, difficulty maintaining a steady depth, hyperventilation, weakness, and a choking sensation, were more frequent among the O2 accident victims compared with divers who did not interrupt their dives. Awareness of any unusual sensation can prevent a potentially dangerous situation from arising.

  7. Blood platelet-derived microparticles release and bubble formation after an open-sea air dive.

    Science.gov (United States)

    Pontier, Jean-Michel; Gempp, Emmanuel; Ignatescu, Mihaela

    2012-10-01

    Bubble-induced platelet aggregation offers an index for evaluating decompression severity in humans and in a rat model of decompression sickness. Endothelial cells, blood platelets, or leukocytes shed microparticles (MP) upon activation and during cell apoptosis. The aim was to study blood platelet MP (PMP) release and bubble formation after a scuba-air dive in field conditions. Healthy, experienced divers were assigned to 1 experimental group (n = 10) with an open-sea air dive to 30 msw for 30 min and 1 control group (n = 5) during head-out water immersion for the same period. Bubble grades were monitored with a pulsed doppler according to Kissman Integrated Severity Score (KISS). Blood samples for platelet count (PC) and PMP (annexin V and CD41) were taken 1 h before and after exposure in both groups. The result showed a decrease in post-dive PC compared with pre-dive values in experimental group with no significant change in the control group. We observed a significant increase in PMP values after the dive while no change was revealed in the control group. There was a significant positive correlation between the PMP values after the dive and the KISS bubble score. The present study highlighted a relationship between the post-dive decrease in PC, platelet MP release, and bubble formation. Release of platelet MPs could reflect bubble-induced platelet aggregation and could play a key role in alteration of the coagulation. Further studies must investigate endothelial and leukocyte MP release in the same field conditions.

  8. Code of Practice for Scientific Diving: Principles for the Safe Practice of Scientific Diving in Different Environments. Unesco Technical Papers in Marine Science 53.

    Science.gov (United States)

    Flemming, N. C., Ed.; Max, M. D., Ed.

    This publication has been prepared to provide scientific divers with guidance on safe practice under varying experimental and environmental conditions. The Code offers advice and recommendations on administrative practices, insurance, terms of employment, medical standards, training standards, dive planning, safety with different breathing gases…

  9. Using Advanced Scientific Diving Technologies to Assess the Underwater Environment

    Energy Technology Data Exchange (ETDEWEB)

    Southard, John A.; Williams, Greg D.; Sargeant, Susan L.; Diefenderfer, Heida L.; Blanton, Michael L.

    2003-03-31

    Scientific diving can provide unique information for addressing complex environmental issues in the marine environment and is applied to a variety of increasingly important issues throughout Puget Sound, including habitat degradation, endangered species, biological availability of contaminants, and the effects of overwater structures and shoreline protection features. The Pacific Northwest National Laboratory, Battelle Marine Sciences Laboratory uses trained scientific divers in conjunction with advanced technologies to collect in-situ information best obtained through direct observation and requiring minimal environmental disturbance. For example, advances in underwater communications allow divers to discuss observations and data collection techniques in real time, both with each other and with personnel on the surface. Other examples include the use of Dual frequency IDentification SONar (DIDSON), an underwater camera used to capture digital images of benthic structures, fish, and organisms during low light and high turbidity levels; the use of voice-narrated underwater video; and the development of sediment collection methods yielding one-meter cores. The combination of using trained scientific SCUBA divers and advanced underwater technologies is a key element in addressing multifaceted environmental problems, resulting in a more comprehensive understanding of the underwater environment and more reliable data with which to make resource management decisions.

  10. Speciation of Iberian diving beetles in Pleistocene refugia (Coleoptera, Dytiscidae).

    Science.gov (United States)

    Ribera, Ignacio; Vogler, Alfried P

    2004-01-01

    The Mediterranean basin is an area of high diversity and endemicity, but the age and origin of its fauna are still largely unknown. Here we use species-level phylogenies based on approximately 1300 base pairs of the genes 16S rRNA and cytochrome oxidase I to establish the relationships of 27 of the 34 endemic Iberian species of diving beetles in the family Dytiscidae, and to investigate their level of divergence. Using a molecular clock approach, 18-19 of these species were estimated to be of Pleistocene origin, with four to six of them from the Late Pleistocene ( approximately 100 000 years). A second, lower speciation frequency peak was assigned to Late Miocene or Early Pliocene. Analysis of the distributional ranges showed that endemic species placed in the tip nodes of the trees are significantly more likely to be allopatric with their sisters than endemic species at lower node levels. Allopatric sister species are also significantly younger than sympatric clades, in agreement with an allopatric mode of speciation and limited subsequent range movement. These results strongly suggest that for some taxa Iberian populations were isolated during the Pleistocene long enough to speciate, and apparently did not expand their ranges to recolonize areas north of the Pyrenees. This is in contradiction to observations from fossil beetles in areas further north, which document large range movements associated with the Pleistocene glacial cycles hypothesized to suppress population isolation and allopatric speciation.

  11. The development of an intermediate-duration tag to characterize the diving behavior of large whales.

    Science.gov (United States)

    Mate, Bruce R; Irvine, Ladd M; Palacios, Daniel M

    2017-01-01

    The development of high-resolution archival tag technologies has revolutionized our understanding of diving behavior in marine taxa such as sharks, turtles, and seals during their wide-ranging movements. However, similar applications for large whales have lagged behind due to the difficulty of keeping tags on the animals for extended periods of time. Here, we present a novel configuration of a transdermally attached biologging device called the Advanced Dive Behavior (ADB) tag. The ADB tag contains sensors that record hydrostatic pressure, three-axis accelerometers, magnetometers, water temperature, and light level, all sampled at 1 Hz. The ADB tag also collects Fastloc GPS locations and can send dive summary data through Service Argos, while staying attached to a whale for typical periods of 3-7 weeks before releasing for recovery and subsequent data download. ADB tags were deployed on sperm whales (Physeter macrocephalus; N = 46), blue whales (Balaenoptera musculus; N = 8), and fin whales (B. physalus; N = 5) from 2007 to 2015, resulting in attachment durations from 0 to 49.6 days, and recording 31 to 2,539 GPS locations and 27 to 2,918 dives per deployment. Archived dive profiles matched well with published dive shapes of each species from short-term records. For blue and fin whales, feeding lunges were detected using peaks in accelerometer data and matched corresponding vertical excursions in the depth record. In sperm whales, rapid orientation changes in the accelerometer data, often during the bottom phase of dives, were likely related to prey pursuit, representing a relative measure of foraging effort. Sperm whales were documented repeatedly diving to, and likely foraging along, the seafloor. Data from the temperature sensor described the vertical structure of the water column in all three species, extending from the surface to depths >1,600 m. In addition to providing information needed to construct multiweek time budgets, the ADB tag is well

  12. ROV Dive Products Dataset for EX1502L3: Caribbean Exploration (ROV) on NOAA Ship Okeanos Explorer between 20150409 and 20150430

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Dataset of folders containing ROV dive products for each ROV dive performed during EX1502L3. The files within the folder are text, image, graph, comma-separated...

  13. Provisional report on diving-related fatalities in Australian waters 2008.

    Science.gov (United States)

    Lippmann, John; Walker, Douglas; Lawrence, Chris; Fock, Andrew; Wodak, Thomas; Harris, Richard; Jamieson, Scott

    2013-03-01

    An individual case review of diving-related deaths, reported as occurring in Australia in 2008, was conducted as part of the DAN Asia-Pacific dive fatality reporting project. The case studies were compiled using reports from witnesses, the police and coroners. In each case, the particular circumstances of the accident and details from the post-mortem examination, where available, are provided. In total, there were 19 reported fatalities (the same as for 2007), 17 involving males. Twelve deaths occurred while snorkelling and/or breath-hold diving,and six while scuba diving. One diver died while using surface-supply breathing apparatus. Two breath-hold divers appear to have died as a result of apnoeic hypoxia, at least one case likely associated with hyperventilation. Two deaths resulted from trauma: one from impact with a boat and the other from an encounter with a great white shark. Cardiac-related issues were thought to have contributed to the deaths of five snorkellers and at least two, possibly three, scuba divers. Trauma from a marine creature, snorkelling or diving alone, apnoeic hypoxia and pre-existing medical conditions were once again features in several deaths in this series.

  14. Provisional report on diving-related fatalities in Australian waters 2010.

    Science.gov (United States)

    Lippmann, John; Lawrence, Christopher; Fock, Andrew; Wodak, Thomas; Jamieson, Scott; Harris, Richard; Walker, Douglas

    2015-09-01

    An individual case review was conducted of known diving-related deaths that occurred in Australia in 2010. The case studies were compiled using statements from witnesses and reports of the police and coroners. In each case, the particular circumstances of the accident and details from the post-mortem examination, where available, are provided. A root cause analysis was made for each case. There were 20 reported fatalities, one less than the previous year. Five of the victims were female (four scuba divers) and 15 were males. Twelve deaths occurred while snorkelling and/or breath-hold diving, seven while scuba diving (one of whom was using a rebreather), and one diver died while using surface supplied breathing apparatus. At least two breath-hold divers likely drowned as a result of apnoeic hypoxia. Cardiac-related issues were thought to have contributed to the deaths of at least three and possibly five snorkellers, and of at least one, possibly two compressed gas divers. Snorkelling or diving alone, poor supervision, apnoeic hypoxia, pre-existing medical conditions, lack of recent experience and unfamiliar and/or poorly-functioning equipment were features in several deaths in this series. Reducing delays to CT-scanning and autopsy and coroners' reports documenting that the victim of a drowning was snorkelling or scuba diving at the time are aspects of the investigation of these fatalities that could be improved.

  15. Drift diving by hooded seals (Cystophora cristata in the Northwest Atlantic Ocean.

    Directory of Open Access Journals (Sweden)

    Julie M Andersen

    Full Text Available Many pinniped species perform a specific dive type, referred to as a 'drift dive', where they drift passively through the water column. This dive type has been suggested to function as a resting/sleeping or food processing dive, and can be used as an indication of feeding success by calculating the daily change in vertical drift rates over time, which reflects the relative fluctuations in buoyancy of the animal as the proportion of lipids in the body change. Northwest Atlantic hooded seals perform drift dives at regular intervals throughout their annual migration across the Northwest Atlantic Ocean. We found that the daily change in drift rate varied with geographic location and the time of year and that this differed between sexes. Positive changes in buoyancy (reflecting increased lipid stores were evident throughout their migration range and although overlapping somewhat, they were not statistically associated with high use areas as indicated by First Passage Time (FPT. Differences in the seasonal fluctuations of buoyancy between males and females suggest that they experience a difference in patterns of energy gain and loss during winter and spring, associated with breeding. The fluctuations in buoyancy around the moulting period were similar between sexes.

  16. Common metabolic constraints on dive duration in endothermic and ectothermic vertebrates

    Directory of Open Access Journals (Sweden)

    April Hayward

    2016-10-01

    Full Text Available Dive duration in air-breathing vertebrates is thought to be constrained by the volume of oxygen stored in the body and the rate at which it is consumed (i.e., “oxygen store/usage hypothesis”. The body mass-dependence of dive duration among endothermic vertebrates is largely supportive of this model, but previous analyses of ectothermic vertebrates show no such body mass-dependence. Here we show that dive duration in both endotherms and ectotherms largely support the oxygen store/usage hypothesis after accounting for the well-established effects of temperature on oxygen consumption rates. Analyses of the body mass and temperature dependence of dive duration in 181 species of endothermic vertebrates and 29 species of ectothermic vertebrates show that dive duration increases as a power law with body mass, and decreases exponentially with increasing temperature. Thus, in the case of ectothermic vertebrates, changes in environmental temperature will likely impact the foraging ecology of divers.

  17. Analytical approximations of diving-wave imaging in constant-gradient medium

    KAUST Repository

    Stovas, Alexey

    2014-06-24

    Full-waveform inversion (FWI) in practical applications is currently used to invert the direct arrivals (diving waves, no reflections) using relatively long offsets. This is driven mainly by the high nonlinearity introduced to the inversion problem when reflection data are included, which in some cases require extremely low frequency for convergence. However, analytical insights into diving waves have lagged behind this sudden interest. We use analytical formulas that describe the diving wave’s behavior and traveltime in a constant-gradient medium to develop insights into the traveltime moveout of diving waves and the image (model) point dispersal (residual) when the wrong velocity is used. The explicit formulations that describe these phenomena reveal the high dependence of diving-wave imaging on the gradient and the initial velocity. The analytical image point residual equation can be further used to scan for the best-fit linear velocity model, which is now becoming a common sight as an initial velocity model for FWI. We determined the accuracy and versatility of these analytical formulas through numerical tests.

  18. Diving under a microscope--a new simple and versatile in vitro diving device for fluorescence and confocal microscopy allowing the controls of hydrostatic pressure, gas pressures, and kinetics of gas saturation.

    Science.gov (United States)

    Wang, Qiong; Belhomme, Marc; Guerrero, François; Mazur, Aleksandra; Lambrechts, Kate; Theron, Michaël

    2013-06-01

    How underwater diving effects the function of the arterial wall and the activities of endothelial cells is the focus of recent studies on decompression sickness. Here we describe an in vitro diving system constructed to achieve real-time monitoring of cell activity during simulated dives under fluorescent microscopy and confocal microscopy. A 1-mL chamber with sapphire windows on both sides and located on the stage of an inverted microscope was built to allow in vitro diving simulation of isolated cells or arteries in which activities during diving are monitored in real-time via fluorescent microscopy and confocal microscopy. Speed of compression and decompression can range from 20 to 2000 kPa/min, allowing systemic pressure to range up to 6500 kPa. Diving temperature is controlled at 37°C. During air dive simulation oxygen partial pressure is optically monitored. Perfusion speed can range from 0.05 to 10 mL/min. The system can support physiological viability of in vitro samples for real-time monitoring of cellular activity during diving. It allows regulations of pressure, speeds of compression and decompression, temperature, gas saturation, and perfusion speed. It will be a valuable tool for hyperbaric research.

  19. DIVING OF OTTERS (LUTRA-LUTRA) IN A MARINE HABITAT - USE OF DEPTHS BY A SINGLE-PREY LOADER

    NARCIS (Netherlands)

    NOLET, BA; WANSINK, DEH; KRUUK, H

    1993-01-01

    1. We test the hypotheses that otters Lutra lutra, diving in a marine habitat, prefer shallow water because (a) breathing is more efficient, (b) searching is more efficient, or (c) body heat is lost less rapidly. 2. Otters were observed along the coast in Shetland over a 3-year period, and dives

  20. Scuba diving and otology: a systematic review with recommendations on diagnosis, treatment and post-operative care.

    Science.gov (United States)

    Livingstone, Devon M; Smith, Kristine A; Lange, Beth

    2017-06-01

    Scuba diving is a popular recreational and professional activity with inherent risks. Complications related to barotrauma and decompression illness can pose significant morbidity to a diver's hearing and balance systems. The majority of dive-related injuries affect the head and neck, particularly the outer, middle and inner ear. Given the high incidence of otologic complications from diving, an evidence-based approach to the diagnosis and treatment of otic pathology is a necessity. We performed a systematic and comprehensive literature review including the pathophysiology, diagnosis, and treatment of otologic pathology related to diving. This included inner, middle, and outer ear anatomic subsites, as well as facial nerve complications, mal de debarquement syndrome, sea sickness and fitness to dive recommendations following otologic surgery. Sixty-two papers on diving and otologic pathology were included in the final analysis. We created a set of succinct evidence-based recommendations on each topic that should inform clinical decisions by otolaryngologists, dive medicine specialists and primary care providers when faced with diving-related patient pathology.

  1. Endothelial function and cardiovascular stress markers after a single dive in aging rats (ApoE knockout rats)

    DEFF Research Database (Denmark)

    Berenji Ardestani, Simin; Pedersen, Michael

    Diving exposes body to a variety of stressors during the dive itself, and gas bubbles that develop during the decompression (ascent) phase. The compressed gas breath augments partial pressure of oxygen (PO2) causing the oxygen concentration of the blood to increase above normal (hyperoxia) likely...... causing excessive oxidative stress, including transient endothelial dysfunction in venous and arterial vessels....

  2. Case Control Study of Type II Decompression Sickness Associated with Patent Foramen Ovale in Experimental No-Decompression Dives

    Science.gov (United States)

    2010-05-01

    animal models or human studies. The presence of a PFO is not disqualifying for diving duty. The U.S. Navy does not currently evaluate asymptomatic diving...Carotid Endarterectomy Using Transcranial Doppler Ultrasonography ," Stroke, Vol. 21, No. 10 (1990), p. 1512. 10. D. C. Adornato et al, "Pathophysiology

  3. Adjustments in the diving time budgets of tufted duck and pochard : Is there evidence for a mix of metabolic pathways?

    NARCIS (Netherlands)

    Carbone, C; DeLeeuw, JJ; Houston, AI

    Predictions of models for the optimal allocation of time over the dive cycle for divers using aerobic and anaerobic respiration, were tested experimentally on the tufted duck, Aythya fuligula, and pochard, A. ferina. Patterns in the dive cycle were highly correlated with water depth. In both

  4. Dry diving as a human model of pulmonary microembolization

    Directory of Open Access Journals (Sweden)

    Željko Dujić

    2009-02-01

    Full Text Available Aim The human model of pulmonary embolism is currently unavailable.The objective of this study was to evaluate whether venousinert gas lung embolization after diving simulation is a modelof pulmonary embolism.Methods Twelve recreational divers underwent two single aircompressions, each in different post-compression posture, in thechamber to 30 m/40 min bottom time with standard decompressionand ascent rates. Cardiopulmonary variables and precordialbubble grade were measured in sitting or lying supine before and40, 70 and 100 min after the respective compression.Results The volume of airways decreased post-compression in supine(24%, p<0.01, as well as in sitting posture (28%, p<0.05.As a sign of lung embolization, the alveolar dead space increasedsignificantly only in supine posture (from 27 to 65 mL, p<0.05.Transcutaneous arterial oxygen tension decreased post-compressionfrom 11,8 to 9,5 kPa in supine posture (p<0.01 and from 11,3to 9,72 kPa in sitting posture (p<0.005. Minute ventilation andbreathing frequency increased significantly only in sitting posture.Cardiovascular depression was suggested from reductions in systolicblood pressure (both postures, heart rate and pulse pressure(sitting posture and from apparent, but not significant decreasesin cardiac output (both postures. Most of the signs were most pronouncedat 40 minutes post-compression and persisted at 100 minpost-compression.Conclusion Small, transient post-compression lung embolizationby inert gas bubbles induces some of the cardiopulmonary signsof pulmonary embolism, especially if the diver is lying after thecompression.

  5. Regulation of stroke pattern and swim speed across a range of current velocities: Diving by common eiders wintering in polynyas in the Canadian Arctic

    NARCIS (Netherlands)

    Heath, J.P.; Gilchrist, H.G.; Ydenberg, R.C.

    2006-01-01

    Swim speed during diving has important energetic consequences. Not only do costs increase as drag rises non-linearly with increasing speed, but speed also affects travel time to foraging patches and therefore time and energy budgets over the entire dive cycle. However, diving behaviour has rarely

  6. Phylogeny of diving beetles reveals a coevolutionary arms race between the sexes.

    Directory of Open Access Journals (Sweden)

    Johannes Bergsten

    Full Text Available BACKGROUND: Darwin illustrated his sexual selection theory with male and female morphology of diving beetles, but maintained a cooperative view of their interaction. Present theory suggests that instead sexual conflict should be a widespread evolutionary force driving both intersexual coevolutionary arms races and speciation. METHODOLOGY/PRINCIPAL FINDINGS: We combined Bayesian phylogenetics, complete taxon sampling and a multi-gene approach to test the arms race scenario on a robust diving beetle phylogeny. As predicted, suction cups in males and modified dorsal surfaces in females showed a pronounced coevolutionary pattern. The female dorsal modifications impair the attachment ability of male suction cups, but each antagonistic novelty in females corresponds to counter-differentiation of suction cups in males. CONCLUSIONS: A recently diverged sibling species pair in Japan is possibly one consequence of this arms race and we suggest that future studies on hypoxia might reveal the key to the extraordinary selection for female counter-adaptations in diving beetles.

  7. SCUBA divers as oceanographic samplers: The potential of dive computers to augment aquatic temperature monitoring

    Science.gov (United States)

    Wright, Serena; Hull, Tom; Sivyer, David B.; Pearce, David; Pinnegar, John K.; Sayer, Martin D. J.; Mogg, Andrew O. M.; Azzopardi, Elaine; Gontarek, Steve; Hyder, Kieran

    2016-01-01

    Monitoring temperature of aquatic waters is of great importance, with modelled, satellite and in-situ data providing invaluable insights into long-term environmental change. However, there is often a lack of depth-resolved temperature measurements. Recreational dive computers routinely record temperature and depth, so could provide an alternate and highly novel source of oceanographic information to fill this data gap. In this study, a citizen science approach was used to obtain over 7,000 scuba diver temperature profiles. The accuracy, offset and lag of temperature records was assessed by comparing dive computers with scientific conductivity-temperature-depth instruments and existing surface temperature data. Our results show that, with processing, dive computers can provide a useful and novel tool with which to augment existing monitoring systems all over the globe, but especially in under-sampled or highly changeable coastal environments. PMID:27445104

  8. Mental abilities and performance efficacy under a simulated 480 meters helium-oxygen saturation diving

    Directory of Open Access Journals (Sweden)

    gonglin ehou

    2015-07-01

    Full Text Available Stress in extreme environment severely disrupts human physiology and mental abilities. The present study investigated the cognition and performance efficacy of four divers during a simulated 480 meters helium-oxygen saturation diving. We analyzed the spatial memory, 2D/3D mental rotation functioning, grip strength, and hand-eye coordination ability in four divers during the 0 – 480 meters compression and decompression processes of the simulated diving. The results showed that except for its mild decrease on grip strength, the high atmosphere pressure condition significantly impaired the hand-eye coordination (especially at 300 meters, the reaction time and correct rate of mental rotation, as well as the spatial memory (especially as 410 meters, showing high individual variability. We conclude that the human cognition and performance efficacy are significantly affected during deep water saturation diving.

  9. Seasonal variability in voluntary dive duration of the Mediterranean loggerhead turtle, Caretta caretta

    Directory of Open Access Journals (Sweden)

    Flegra Bentivegna

    2003-09-01

    Full Text Available We characterised the effect of seasonal fluctuations in water temperature (Tw on the nonventilatory period (NVP of Mediterranean loggerhead turtles, Caretta caretta. Ten captive turtles, that were subject to the natural variations in Tw found in the Gulf of Naples, dived significantly longer when Tw decreased. More than 50% of summer and winter dives lasted between 2 and 10 min; the maximum dive duration (120 min occurred in winter at a Tw of 13°C. The longest NVP coincided with a low level of activity and a lower food consumption. This, and a reduced metabolic rate consequent to acclimatisation to a low Tw were likely to have influenced NVP.

  10. Calling under pressure: Short-finned pilot whales make social calls during deep foraging dives

    DEFF Research Database (Denmark)

    Jensen, Frants Havmand; Marrero Perez, Jacobo; Johnson, Mark

    2011-01-01

    Toothed whales rely on sound to echolocate prey and communicate with conspecifics, but little is known about how extreme pressure affects pneumatic sound production in deep-diving species with a limited air supply. The short-finned pilot whale (Globicephala macrorhynchus) is a highly social species...... among the deep-diving toothed whales, in which individuals socialize at the surface but leave their social group in pursuit of prey at depths of up to 1000 m. To investigate if these animals communicate acoustically at depth and test whether hydrostatic pressure affects communication signals, acoustic...... DTAGs logging sound, depth and orientation were attached to 12 pilot whales. Tagged whales produced tonal calls during deep foraging dives at depths of up to 800 m. Mean call output and duration decreased with depth despite the increased distance to conspecifics at the surface. This shows...

  11. Foul or dive? Motor contributions to judging ambiguous foul situations in football.

    Science.gov (United States)

    Renden, Peter G; Kerstens, Sander; Oudejans, Raôul R D; Cañal-Bruland, Rouwen

    2014-01-01

    Football (soccer) referees frequently face situations in which they have to distinguish dives and fouls. Yet, little is known about the contributing factors that characterise the ability to judge these ambiguous situations correctly. To this end, in the current article we tested the hypothesis that motor experience of observers contributes to the visual identification of deceptive actions. Thereto, we asked skilled football referees, skilled football players, wheelchair bounded football fans (thus with limited motor experience) and novices to judge whether potential tackle situations in football were either fouls or dives. Results revealed that the referees (accuracy 72.2%, s=6.2) and players (accuracy 72.0%, s=6.4) were better at discriminating fouls and dives than the fans (accuracy 61.1%, s=7.2) and the novices (accuracy 57.4%, s=7.0) (P < 0.001). The results seem to point to an added value of motor experience in detecting deceptive movements.

  12. AFSC/ABL: Rockfish Habitat Dive Video Transects

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — Many species of commercially valuable rockfish (Sebastes spp.) inhabit waters on the outer continental shelf in the Gulf of Alaska typically between depths of...

  13. Understanding scuba diving fatalities: carbon dioxide concentrations in intra-cardiac gas.

    Science.gov (United States)

    Varlet, Vincent; Dominguez, Alejandro; Augsburger, Marc; Lossois, Maisy; Egger, Coraline; Palmiere, Cristian; Vilarino, Raquel; Grabherr, Silke

    2017-06-01

    Important developments in the diagnosis of scuba diving fatalities have been made thanks to forensic imaging tool improvements. Multi-detector computed tomography (MDCT) permits reliable interpretation of the overall gaseous distribution in the cadaver. However, due to post-mortem delay, the radiological interpretation is often doubtful because the distinction between gas related to the dive and post-mortem decomposition artifactual gases becomes less obvious. We present six cases of fatal scuba diving showing gas in the heart and other vasculature. Carbon dioxide (CO₂) in cardiac gas measured by gas chromatography coupled to thermal conductivity detection were employed to distinguish decomposition from embolism based on the detection of decomposition gases (hydrogen, hydrogen sulfide and methane) and to confirm arterial gas embolism (AGE) or post-mortem offgasing diagnoses. A Radiological Alteration Index (RAI) was calculated from the scan. Based on the dive history, the intra-cadaveric gas was diagnosed as deriving from decomposition (one case, minimal RAI of 61), post-mortem decompression artifacts (two cases, intermediate RAI between 60 and 85) and barotrauma/AGE (three cases, maximal RAI between 85 and 100), illustrating a large distribution inside the bodies. MDCT scans should be interpreted simultaneously with compositional analysis of intra-cadaveric gases. Intra-cadaveric gas sampling and analysis may become useful tools for understanding and diagnosing scuba diving fatalities. In cases with short post-mortem delays, the CO₂ concentration of the cardiac gas provides relevant information about the circumstances and cause of death when this parameter is interpreted in combination with the diving profile.

  14. Rapid maturation of the muscle biochemistry that supports diving in Pacific walruses (Odobenus rosmarus divergens)

    Science.gov (United States)

    Norem, Shawn R.; Jay, Chadwick V.; Burns, Jennifer M.; Fischbach, Anthony S.

    2015-01-01

    Physiological constraints dictate animals’ ability to exploit habitats. For marine mammals, it is important to quantify physiological limits that influence diving and their ability to alter foraging behaviors. We characterized age-specific dive limits of walruses by measuring anaerobic (acid-buffering capacity) and aerobic (myoglobin content) capacities of the muscles that power hind (longissimus dorsi) and fore (supraspinatus) flipper propulsion. Mean buffering capacities were similar across muscles and age classes (a fetus, five neonatal calves, a 3 month old and 20 adults), ranging from 41.31 to 54.14 slykes and 42.00 to 46.93 slykes in the longissimus and supraspinatus, respectively. Mean myoglobin in the fetus and neonatal calves fell within a narrow range (longissimus: 0.92–1.68 g 100 g−1 wet muscle mass; supraspinatus: 0.88–1.64 g 100 g−1 wet muscle mass). By 3 months post-partum, myoglobin in the longissimus increased by 79%, but levels in the supraspinatus remained unaltered. From 3 months post-partum to adulthood, myoglobin increased by an additional 26% in the longissimus and increased by 126% in the supraspinatus; myoglobin remained greater in the longissimus compared with the supraspinatus. Walruses are unique among marine mammals because they are born with a mature muscle acid-buffering capacity and attain mature myoglobin content early in life. Despite rapid physiological development, small body size limits the diving capacity of immature walruses and extreme sexual dimorphism reduces the diving capacity of adult females compared with adult males. Thus, free-ranging immature walruses likely exhibit the shortest foraging dives while adult males are capable of the longest foraging dives.

  15. High incidence of venous and arterial gas emboli at rest after trimix diving without protocol violations.

    Science.gov (United States)

    Ljubkovic, Marko; Marinovic, Jasna; Obad, Ante; Breskovic, Toni; Gaustad, Svein E; Dujic, Zeljko

    2010-12-01

    SCUBA diving is associated with generation of gas emboli due to gas release from the supersaturated tissues during decompression. Gas emboli arise mostly on the venous side of circulation, and they are usually eliminated as they pass through the lung vessels. Arterialization of venous gas emboli (VGE) is seldom reported, and it is potentially related to neurological damage and development of decompression sickness. The goal of the present study was to evaluate the generation of VGE in a group of divers using a mixture of compressed oxygen, helium, and nitrogen (trimix) and to probe for their potential appearance in arterial circulation. Seven experienced male divers performed three dives in consecutive days according to trimix diving and decompression protocols generated by V-planner, a software program based on the Varying Permeability Model. The occurrence of VGE was monitored ultrasonographically for up to 90 min after surfacing, and the images were graded on a scale from 0 to 5. The performed diving activities resulted in a substantial amount of VGE detected in the right cardiac chambers and their frequent passage to the arterial side, in 9 of 21 total dives (42%) and in 5 of 7 divers (71%). Concomitant measurement of mean pulmonary artery pressure revealed a nearly twofold augmentation, from 13.6 ± 2.8, 19.2 ± 9.2, and 14.7 ± 3.3 mmHg assessed before the first, second, and the third dive, respectively, to 26.1 ± 5.4, 27.5 ± 7.3, and 27.4 ± 5.9 mmHg detected after surfacing. No acute decompression-related disorders were identified. The observed high gas bubble loads and repeated microemboli in systemic circulation raise questions about the possibility of long-term adverse effects and warrant further investigation.

  16. Bubble formation and endothelial function before and after 3 months of dive training.

    Science.gov (United States)

    Pontier, Jean-Michel; Guerrero, François; Castagna, Olivier

    2009-01-01

    It has been suggested that repeated compression-decompression cycles reduce diver susceptibility to decompression sickness (DCS). This study examined whether intensive scuba dive training would reduce bubble formation and modulate endothelial function as shown by skin circulation. There were 22 military divers who were studied before and after a 90-d program of physical training and open-sea air diving (mean 67 dives total). Skin blood flow in the forearm was measured at rest (baseline), during post-occlusive hyperemia (endothelium-dependent vasodilatation), and with local heating to 42 degrees C (maximal vasodilatation). Subjects were also examined by pulsed Doppler for venous bubbles 30, 60, and 90 min after surfacing from a hyperbaric exposure to 400 kPa (30 msw) for 30 min in a dry chamber. None of the divers experienced DCS during the training period. There was no change in weight, body mass index, maximal oxygen uptake, or endothelial function. Bubble grades by the Kisman Integrated Severity Score were significantly decreased immediately after the diving training period (3.6 +/- 9.2 vs. 16.4 +/- 14.3) and increased 3 mo after this period (10.3 +/- 13.9 vs. 3.6 +/- 9.2). The results highlight that repeated scuba dives and regular physical exercise activity reduce bubble formation and probably have a protective effect against DCS risk. Although this phenomenon has been observed for decades, the mechanism remains complex and the results cannot elucidate the effects of physical exercise and NO production. Bubble formation could activate the stress response which could be the basis for diving acclimatization.

  17. Feather Vibration as a Stimulus for Sensing Incipient Separation in Falcon Diving Flight

    OpenAIRE

    Brücker, C; Schlegel, D.; Triep, M.

    2016-01-01

    Based on our preceding studies on the aerodynamics of a falcoperegrinus in diving flight along a vertical dam it is known that even when the body shape of the bird is rather streamlined in V-shape some feathers tips may elevate in certain regions of the body. These regions were identified in wind tunnel tests for typical diving flight conditions as regions of locally separated flow. A life-size model in V-shape of a falcoperegrinus with artificial feathers fixed along the body was studied in ...

  18. Scuba diving induces nitric oxide synthesis and the expression of inflammatory and regulatory genes of the immune response in neutrophils.

    Science.gov (United States)

    Sureda, Antoni; Batle, Juan M; Capó, Xavier; Martorell, Miquel; Córdova, Alfredo; Tur, Josep A; Pons, Antoni

    2014-09-01

    Scuba diving, characterized by hyperoxia and hyperbaria, could increase reactive oxygen species production which acts as signaling molecules to induce adaptation against oxidative stress. The aim was to study the effects of scuba diving immersion on neutrophil inflammatory response, the induction of oxidative damage, and the NO synthesis. Nine male divers performed a dive at 50 m depth for a total time of 35 min. Blood samples were obtained at rest before the dive, after the dive, and 3 h after the diving session. Markers of oxidative and nitrosative damage, nitrite, and the gene expression of genes related with the synthesis of nitric oxide and lipid mediators, cytokine synthesis, and inflammation were determined in neutrophils. The mRNA levels of genes related with the inflammatory and immune response of neutrophils, except TNF-α, myeloperoxidase, and toll-like receptor (TLR) 2, significantly increased after the recovery period respect to predive and postdive levels. NF-κB, IL-6, and TLR4 gene expression reported significant differences immediately after diving respect to the predive values. Protein nitrotyrosine levels significantly rose after diving and remained high during recovery, whereas no significant differences were reported in malondialdehyde. Neutrophil nitrite levels as indicative of inducible nitric oxide synthase (iNOS) activity progressively increased after diving and recovery. The iNOS protein levels maintained the basal values in all situations. Scuba diving which combines hyperoxia, hyperbaria, and acute exercise induces nitrosative damage with increased nitrotyrosine levels and an inflammatory response in neutrophils. Copyright © 2014 the American Physiological Society.

  19. High diving metabolic rate indicated by high-speed transit to depth in negatively buoyant long-finned pilot whales.

    Science.gov (United States)

    Aoki, Kagari; Sato, Katsufumi; Isojunno, Saana; Narazaki, Tomoko; Miller, Patrick J O

    2017-10-15

    To maximize foraging duration at depth, diving mammals are expected to use the lowest cost optimal speed during descent and ascent transit and to minimize the cost of transport by achieving neutral buoyancy. Here, we outfitted 18 deep-diving long-finned pilot whales with multi-sensor data loggers and found indications that their diving strategy is associated with higher costs than those of other deep-diving toothed whales. Theoretical models predict that optimal speed is proportional to (basal metabolic rate/drag)1/3 and therefore to body mass0.05 The transit speed of tagged animals (2.7±0.3 m s-1) was substantially higher than the optimal speed predicted from body mass (1.4-1.7 m s-1). According to the theoretical models, this choice of high transit speed, given a similar drag coefficient (median, 0.0035) to that in other cetaceans, indicated greater basal metabolic costs during diving than for other cetaceans. This could explain the comparatively short duration (8.9±1.5 min) of their deep dives (maximum depth, 444±85 m). Hydrodynamic gliding models indicated negative buoyancy of tissue body density (1038.8±1.6 kg m-3, ±95% credible interval, CI) and similar diving gas volume (34.6±0.6 ml kg-1, ±95% CI) to those in other deep-diving toothed whales. High diving metabolic rate and costly negative buoyancy imply a 'spend more, gain more' strategy of long-finned pilot whales, differing from that in other deep-diving toothed whales, which limits the costs of locomotion during foraging. We also found that net buoyancy affected the optimal speed: high transit speeds gradually decreased during ascent as the whales approached neutral buoyancy owing to gas expansion. © 2017. Published by The Company of Biologists Ltd.

  20. Joint position statement on persistent foramen ovale (PFO) and diving. South Pacific Underwater Medicine Society (SPUMS) and the United Kingdom Sports Diving Medical Committee (UKSDMC).

    Science.gov (United States)

    Smart, David; Mitchell, Simon; Wilmshurst, Peter; Turner, Mark; Banham, Neil

    2015-06-01

    This consensus statement is the result of a workshop at the SPUMS Annual Scientific Meeting 2014 with representatives of the UK Sports Diving Medical Committee (UKSDMC) present, and subsequent discussions including the entire UKSDMC. Right-to-left shunt across a persistent or patent foramen ovale (PFO) is a risk factor for some types of decompression illness. It was agreed that routine screening for PFO is not currently justifiable, but certain high risk sub-groups can be identified. Divers with a history of cerebral, spinal, inner-ear or cutaneous decompression illness, migraine with aura, a family history of PFO or atrial septal defect and those with other forms of congenital heart disease are considered to be at higher risk. For these individuals, screening should be considered. If screening is undertaken it should be by bubble contrast transthoracic echocardiography with provocative manoeuvres, including Valsalva release and sniffing. Appropriate quality control is important. If a shunt is present, advice should be provided by an experienced diving physician taking into account the clinical context and the size of shunt. Reduction in gas load by limiting depth, repetitive dives and avoiding lifting and straining may all be appropriate. Divers may consider transcatheter device closure of the PFO in order to return to normal diving. If transcatheter PFO closure is undertaken, repeat bubble contrast echocardiography must be performed to confirm adequate reduction or abolition of the right-to-left shunt, and the diver should have stopped taking potent anti-platelet therapy (aspirin is acceptable).

  1. 78 FR 18349 - Federal Acquisition Regulation; Information Collection; Commercial Item Acquisitions

    Science.gov (United States)

    2013-03-26

    ... Secretariat (MVCB), 1275 First Street NE., Washington, DC 20417. ATTN: Hada Flowers/IC 9000-0136, Commercial... Regulation; Information Collection; Commercial Item Acquisitions AGENCY: Department of Defense (DOD), General... collection requirement concerning the clauses and provisions required for use in commercial item acquisitions...

  2. Construction of Tests in the Cognitive and Psychomotor Domains for Skin and Scuba Diving.

    Science.gov (United States)

    McCarthy, Jean

    The fundamental purposes of this study were to develop mastery tests in the cognitive and psychomotor domains for skin and scuba diving and to establish validity and reliability for the tests. A table of specifications was developed for each domain, and a pilot study refined the initial test batteries into their final form. In the main study,…

  3. Diving into Troubled Waters: Sexual Discrimination in a Male Dominated Recreational Culture.

    Science.gov (United States)

    Lagache, Edouard

    This paper presents results of a study of sex discrimination in the culture of scuba divers. The research grew out of class related conflicts that permitted observation in ethnographic field work, the character of gender relations in the recreational activity of scuba diving. The project was intended to investigate the role of communities of…

  4. Surveying, Modeling and 3d Representation of a wreck for Diving Purposes: Cargo Ship "vera"

    Science.gov (United States)

    Ktistis, A.; Tokmakidis, P.; Papadimitriou, K.

    2017-02-01

    This paper presents the results from an underwater recording of the stern part of a contemporary cargo-ship wreck. The aim of this survey was to create 3D representations of this wreck mainly for recreational diving purposes. The key points of this paper are: a) the implementation of the underwater recording at a diving site; b) the reconstruction of a 3d model from data that have been captured by recreational divers; and c) the development of a set of products to be used by the general public for the ex situ presentation or for the in situ navigation. The idea behind this project is to define a simple and low cost procedure for the surveying, modeling and 3D representation of a diving site. The perspective of our team is to repeat the proposed methodology for the documentation and the promotion of other diving sites with cultural features, as well as to train recreational divers in underwater surveying procedures towards public awareness and community engagement in the maritime heritage.

  5. USING DIRECT-PUSH TOOLS TO MAP HYDROSTRATIGRAPHY AND PREDICT MTBE PLUME DIVING

    Science.gov (United States)

    MTBE plumes have been documented to dive beneath screened intervals of conventional monitoring well networks at a number of LUST sites. This behavior makes these plumes difficult both to detect and remediate. Electrical conductivity logging and pneumatic slug testing performed in...

  6. A CATALOG OF GROUND WATER FLOW SOLUTIONS FOR PLUME DIVING CALCULATIONS

    Science.gov (United States)

    This report focuses on the problem of diving plumes, a term which generally refers to plumes that go deeper into aquifers with distances from their sources. This document presents the mathematical basis of software for real-time development and refinement of site conceptual model...

  7. Body contact and synchronous diving in long-finned pilot whales

    NARCIS (Netherlands)

    Aokia, K.; Sakai, M.; Miller, P.J.O.; Visser, F.; Sato, K.

    2013-01-01

    Synchronous behavior, as a form of social interaction, has been widely reported for odontocete cetaceans observed at the sea surface. However, few studies have quantified synchronous behavior underwater. Using data from an animal-borne data recorder and camera, we described how a pair of deep-diving

  8. Lower-extremity isokinetic strength ratios of elite springboard and platform diving athletes.

    Science.gov (United States)

    Vieira, Amilton; Alex, Savio; Martorelli, André; Brown, Lee E; Moreira, Ricardo; Bottaro, Martim

    2017-05-01

    The purpose of the present study was to examine knee extensor and flexor muscle strength ratios of an elite group of diving athletes. Sixteen divers (10 females and 6 males) from the Brazil national team were assessed for lower-body strength. They had participated in international competitions such as the 2016 Olympic Games and 2015 Pan American Games. The dynamic concentric torque of their knee flexor and extensor muscles were evaluated using a Biodex isokinetic dynamometer. Bilateral tests were performed at 60º s-1. Flexor to extensor (F/E) peak torque ratio and percentage bilateral difference (BD%) was also measured. The results revealed that elite diving athletes produced higher than usual reported in previous studies for relative knee extension torque (3.2 for females and 3.6 for males N∙m∙kg-1). However, they presented low levels of knee flexor torque (1.5 for females and 1.8 for males N∙m∙kg-1). These results are reflected in a low F/E ratio (0.39 to 0.49). Males presented a greater BD% in knee flexors when compared to females (12.4% vs 6.6%). Elite diving athletes demonstrated high knee extensor and low knee flexor strength. This partially explains their low F/E ratio, which might increase risk of knee injuries. Strength and conditioning programs should strive to correct knee strength imbalances in diving athletes where necessary.

  9. Diving behavior of the reef manta ray links coral reefs with adjacent deep pelagic habitats

    KAUST Repository

    Braun, Camrin D.

    2014-02-06

    Recent successful efforts to increase protection for manta rays has highlighted the lack of basic ecological information, including vertical and horizontal movement patterns, available for these species. We deployed pop-up satellite archival transmitting tags on nine reef manta rays, Manta alfredi, to determine diving behaviors and vertical habitat use. Transmitted and archived data were obtained from seven tagged mantas over deployment periods of 102-188 days, including three recovered tags containing 2.6 million depth, temperature, and light level data points collected every 10 or 15 seconds. Mantas frequented the upper 10 m during daylight hours and tended to occupy deeper water throughout the night. Six of the seven individuals performed a cumulative 76 deep dives (>150 m) with one individual reaching 432 m, extending the known depth range of this coastal, reef-oriented species and confirming its role as an ecological link between epipelagic and mesopelagic habitats. Mean vertical velocities calculated from high-resolution dive data (62 dives >150 m) from three individuals suggested that mantas may use gliding behavior during travel and that this behavior may prove more efficient than continuous horizontal swimming. The behaviors in this study indicate manta rays provide a previously unknown link between the epi- and mesopelagic layers of an extremely oligotrophic marine environment and provide evidence of a third marine species that utilizes gliding to maximize movement efficiency. © 2014 Braun et al.

  10. Biosonar, diving and movements of two tagged white-beaked dolphin in Icelandic waters

    DEFF Research Database (Denmark)

    Rasmussen, Marianne H.; Akamatsu, Tomonari; Teilmann, Jonas

    2013-01-01

    For the first time bio-logging tags were attached to free-ranging white-beaked dolphins, Lagenorhynchus albirostris. A satellite tag was attached to one animal while an acoustic A-tag, a time-depth recorder and a VHF transmitter complex was attached to a second dolphin with a suction cup....... The satellite tag transmitted for 201 days, during which time the dolphin stayed in the coastal waters of western Iceland. The acoustic tag complex was on the second animal for 13 hours and 40 minutes and provided the first insight in echolocation behaviour of a free-ranging white-beaked dolphin. The tag...... registered 162 dives. The dolphin dove to a maximum depth of 45 m, which is about the depth of the bay in which the dolphin was swimming. Two basic types of dives were identified; U-shaped and V-shaped dives. The dolphin used more time in U-shaped dives, more clicks and sonar signals with shorter click...

  11. Marine foraging ecology influences mercury bioaccumulation in deep-diving northern elephant seals

    Science.gov (United States)

    Peterson, Sarah H.; Ackerman, Joshua T.; Costa, Daniel P.

    2015-01-01

    Mercury contamination of oceans is prevalent worldwide and methylmercury concentrations in the mesopelagic zone (200–1000 m) are increasing more rapidly than in surface waters. Yet mercury bioaccumulation in mesopelagic predators has been understudied. Northern elephant seals (Mirounga angustirostris) biannually travel thousands of kilometres to forage within coastal and open-ocean regions of the northeast Pacific Ocean. We coupled satellite telemetry, diving behaviour and stable isotopes (carbon and nitrogen) from 77 adult females, and showed that variability among individuals in foraging location, diving depth and δ13C values were correlated with mercury concentrations in blood and muscle. We identified three clusters of foraging strategies, and these resulted in substantially different mercury concentrations: (i) deeper-diving and offshore-foraging seals had the greatest mercury concentrations, (ii) shallower-diving and offshore-foraging seals had intermediate levels, and (iii) coastal and more northerly foraging seals had the lowest mercury concentrations. Additionally, mercury concentrations were lower at the end of the seven-month-long foraging trip (n = 31) than after the two-month- long post-breeding trip (n = 46). Our results indicate that foraging behaviour influences mercury exposure and mesopelagic predators foraging in the northeast Pacific Ocean may be at high risk for mercury bioaccumulation.

  12. Locomotor muscle profile of a deep (Kogia breviceps) versus shallow (Tursiops truncatus) diving cetacean.

    Science.gov (United States)

    Kielhorn, Caitlin E; Dillaman, Richard M; Kinsey, Stephen T; McLellan, William A; Gay, D Mark; Dearolf, Jennifer L; Pabst, D Ann

    2013-06-01

    When a marine mammal dives, breathing and locomotion are mechanically uncoupled, and its locomotor muscle must power swimming when oxygen is limited. The morphology of that muscle provides insight into both its oxygen storage capacity and its rate of oxygen consumption. This study investigated the m. longissimus dorsi, an epaxial swimming muscle, in the long duration, deep-diving pygmy sperm whale (Kogia breviceps) and the short duration, shallow-diving Atlantic bottlenose dolphin (Tursiops truncatus). Muscle myoglobin content, fiber type profile (based upon myosin ATPase and succinate dehydrogenase assays), and fiber size were measured for five adult specimens of each species. In addition, a photometric analysis of sections stained for succinate dehydrogenase was used to create an index of mitochondrial density. The m. longissimus dorsi of K. breviceps displayed significantly a) higher myoglobin content, b) larger proportion of Type I (slow oxidative) fibers by area, c) larger mean fiber diameters, and d) lower indices of mitochondrial density than that of T. truncatus. Thus, this primary swimming muscle of K. breviceps has greater oxygen storage capacity, reduced ATP demand, and likely a reduced rate of oxygen consumption relative to that of T. truncatus. The locomotor muscle of K. breviceps appears able to ration its high onboard oxygen stores, a feature that may allow this species to conduct relatively long duration, deep dives aerobically. Copyright © 2013 Wiley Periodicals, Inc.

  13. Correction for adiabatic effects in lethe calculated instantaneous gas consumption of scuba dives

    NARCIS (Netherlands)

    Schellart, Nico A. M.; Le Péchon, Jean-Claude

    2015-01-01

    Introduction: In scuba-diving practice, instantaneous gas consumption is generally calculated from the fall in cylinder pressure without considering the effects of water temperature (heat transfer) and adiabatic processes. We aimed to develop a simple but precise method for calculating the

  14. Evolution of subterranean diving beetles (Coleoptera: Dytiscidae: Hydroporini, Bidessini) in the arid zone of Australia.

    Science.gov (United States)

    Leys, Remko; Watts, Chris H S; Cooper, Steve J B; Humphreys, William F

    2003-12-01

    Calcrete aquifers in arid inland Australia have recently been found to contain the world's most diverse assemblage of subterranean diving beetles (Coleoptera: Dytiscidae). In this study we test whether the adaptive shift hypothesis (ASH) or the climatic relict hypothesis (CRH) is the most likely mode of evolution for the Australian subterranean diving beetles by using a phylogeny based on two sequenced fragments of mitochondrial genes (CO1 and 16S-tRNA-ND1) and linearized using a relaxed molecular clock method. Most individual calcrete aquifers contain an assemblage of diving beetle species of distantly related lineages and/or a single pair of sister species that significantly differ in size and morphology. Evolutionary transitions from surface to subterranean life took place in a relatively small time frame between nine and four million years ago. Most of the variation in divergence times of the sympatric sister species is explained by the variation in latitude of the localities, which correlates with the onset of aridity from the north to the south and with an aridity maximum in the Early Pliocene (five mya). We conclude that individual calcrete aquifers were colonized by several distantly related diving beetle lineages. Several lines of evidence from molecular clock analyses support the CRH, indicating that all evolutionary transitions took place during the Late Miocene and Early Pliocene as a result of aridification.

  15. 75 FR 14493 - Safety Zone; Dive Platform, Pago Pago Harbor, American Samoa

    Science.gov (United States)

    2010-03-26

    ... temporary safety zone around the USNS Sioux or M/V EL LOBO GRANDE II dive platform and the 332-foot Tanker... CHEHALIS wreck. Background and Purpose On October 7, 1949 the 4,130-ton gasoline tanker CHEHALIS sank in... management systems practices) that are developed or adopted by voluntary consensus standards bodies. This...

  16. Diving behavior of the reef manta ray links coral reefs with adjacent deep pelagic habitats.

    Directory of Open Access Journals (Sweden)

    Camrin D Braun

    Full Text Available Recent successful efforts to increase protection for manta rays has highlighted the lack of basic ecological information, including vertical and horizontal movement patterns, available for these species. We deployed pop-up satellite archival transmitting tags on nine reef manta rays, Manta alfredi, to determine diving behaviors and vertical habitat use. Transmitted and archived data were obtained from seven tagged mantas over deployment periods of 102-188 days, including three recovered tags containing 2.6 million depth, temperature, and light level data points collected every 10 or 15 seconds. Mantas frequented the upper 10 m during daylight hours and tended to occupy deeper water throughout the night. Six of the seven individuals performed a cumulative 76 deep dives (>150 m with one individual reaching 432 m, extending the known depth range of this coastal, reef-oriented species and confirming its role as an ecological link between epipelagic and mesopelagic habitats. Mean vertical velocities calculated from high-resolution dive data (62 dives >150 m from three individuals suggested that mantas may use gliding behavior during travel and that this behavior may prove more efficient than continuous horizontal swimming. The behaviors in this study indicate manta rays provide a previously unknown link between the epi- and mesopelagic layers of an extremely oligotrophic marine environment and provide evidence of a third marine species that utilizes gliding to maximize movement efficiency.

  17. Foul or dive? Motor contributions to judging ambiguous foul situations in football

    NARCIS (Netherlands)

    Renden, P.G.; Kerstens, S.; Oudejans, R.R.D.; Canal Bruland, R.

    2014-01-01

    Football (soccer) referees frequently face situations in which they have to distinguish dives and fouls. Yet, little is known about the contributing factors that characterise the ability to judge these ambiguous situations correctly. To this end, in the current article we tested the hypothesis that

  18. 36 CFR 3.18 - May I snorkel or underwater dive in park waters?

    Science.gov (United States)

    2010-07-01

    ... 36 Parks, Forests, and Public Property 1 2010-07-01 2010-07-01 false May I snorkel or underwater dive in park waters? 3.18 Section 3.18 Parks, Forests, and Public Property NATIONAL PARK SERVICE... surface, submerging or surfacing the diver must remain within a 100 feet horizontal radius of the diver...

  19. Forensic Case Reports Presenting Immersion Pulmonary Edema as a Differential Diagnosis in Fatal Diving Accidents

    DEFF Research Database (Denmark)

    Vinkel, Julie; Bak, Peter; Juel Thiis Knudsen, Peter

    2018-01-01

    deaths, and through a thorough analysis of each case, including both diving physiology and forensic pathology, we present IPE as a differential diagnosis to drowning in four cases. Our findings propose that; absence of watery content in the stomach and conducting airways, and liquid filled lungs without...

  20. Socio-economic aspects of the tiger shark diving industry within the ...

    African Journals Online (AJOL)

    Understanding socio-economic aspects of the tiger shark Galeocerdo cuvier diving industry, including information on participant expectations, experiences and expenditure, is necessary for the effective management of the Aliwal Shoal Marine Protected Area on the east coast of South Africa. Between January and ...

  1. A comparison of blood nitric oxide metabolites and hemoglobin functional properties among diving mammals

    DEFF Research Database (Denmark)

    Fago, Angela; Parraga, Daniel Garcia; Petersen, Elin E

    2017-01-01

    in regulating blood flow, we measured concentration of nitrite and S-nitrosothiols (SNO), two metabolites of the vasodilator nitric oxide (NO), in the blood of 5 species of marine mammals differing in their dive duration: bottlenose dolphin, South American sea lion, harbor seal, walrus and beluga whale. We also...

  2. Genetic predisposition to breath-hold diving-induced hemoptysis: Preliminary study.

    OpenAIRE

    Cialoni, Danilo; Marabotti, Claudio C; Sponsiello, Nicola; Pieri, Massimo; Balestra, Costantino; Lucchini, Vittorio V; Marroni, Alessandro

    2015-01-01

    Breath-hold diving-induced hemoptysis (BH-DIH) has been reported in about 25% breath-hold divers (BHD) and is characterized by dyspnea, coughing, hemoptysis and chest pain. We investigated whether eNOS G894T, eNOS T786C and ACE insertion/deletion I/D genetic variants, are possible BH-DIH risk factors.

  3. Tools to Compare Diving-Animal Kinematics with Acoustic Behavior and Exposure

    Science.gov (United States)

    2011-09-30

    deterrent study (Figure 2), supported by the NOAA Gulf Apex Predator-prey program. These investigators succeeded without on-site support from the PI...Hildebrand. 2006. Kinematics of foraging dives and lunge -feeding in fin whales. J. Exp. Biol. 209:1231–1244. [published, refereed] Henthorn, R

  4. Co-discoverer of evidence for quarks killed in diving accident

    CERN Multimedia

    Nadis, S

    1999-01-01

    Henry Kendall died last week while scuba diving in a Florida lake. He was awarded the Nobel prize in 1990 along with Friedman and Taylor, for their work in the late 1960s that provided the first direct evidence for quarks (1 page).

  5. Bioenergetics and diving activity of internesting leatherback turtles Dermochelys coriacea at Parque Nacional Marino Las Baulas, Costa Rica.

    Science.gov (United States)

    Wallace, Bryan P; Williams, Cassondra L; Paladino, Frank V; Morreale, Stephen J; Lindstrom, R Todd; Spotila, James R

    2005-10-01

    Physiology, environment and life history demands interact to influence marine turtle bioenergetics and activity. However, metabolism and diving behavior of free-swimming marine turtles have not been measured simultaneously. Using doubly labeled water, we obtained the first field metabolic rates (FMRs; 0.20-0.74 W kg(-1)) and water fluxes (16-30% TBW day(-1), where TBW=total body water) for free-ranging marine turtles and combined these data with dive information from electronic archival tags to investigate the bioenergetics and diving activity of reproductive adult female leatherback turtles Dermochelys coriacea. Mean dive durations (7.8+/-2.4 min (+/-1 s.d.), bottom times (2.7+/-0.8 min), and percentage of time spent in water temperatures (Tw) or =0.99). This suggests that low FMRs and activity levels, combined with shuttling between different water temperatures, could allow leatherbacks to avoid overheating while in warm tropical waters. Additionally, internesting leatherback dive durations were consistently shorter than aerobic dive limits calculated from our FMRs (11.7-44.3 min). Our results indicate that internesting female leatherbacks maintained low FMRs and activity levels, thereby spending relatively little energy while active at sea. Future studies should incorporate data on metabolic rate, dive patterns, water temperatures, and body temperatures to develop further the relationship between physiological and life history demands and marine turtle bioenergetics and activity.

  6. Commercial Buildings Characteristics, 1992

    Energy Technology Data Exchange (ETDEWEB)

    1994-04-29

    Commercial Buildings Characteristics 1992 presents statistics about the number, type, and size of commercial buildings in the United States as well as their energy-related characteristics. These data are collected in the Commercial Buildings Energy Consumption Survey (CBECS), a national survey of buildings in the commercial sector. The 1992 CBECS is the fifth in a series conducted since 1979 by the Energy Information Administration. Approximately 6,600 commercial buildings were surveyed, representing the characteristics and energy consumption of 4.8 million commercial buildings and 67.9 billion square feet of commercial floorspace nationwide. Overall, the amount of commercial floorspace in the United States increased an average of 2.4 percent annually between 1989 and 1992, while the number of commercial buildings increased an average of 2.0 percent annually.

  7. Diving response after a one-week diet and overnight fasting.

    Science.gov (United States)

    Ghiani, Giovanna; Marongiu, Elisabetta; Olla, Sergio; Pinna, Marco; Pusceddu, Matteo; Palazzolo, Girolamo; Sanna, Irene; Roberto, Silvana; Crisafulli, Antonio; Tocco, Filippo

    2016-01-01

    We hypothesized that overnight fasting after a short dietary period, especially with carbohydrates, could allow performing breath-hold diving with no restraint for diaphragm excursion and blood shift and without any increase of metabolism, and in turn improve the diving response. During two separate sessions, 8 divers carried out two trials: (A) a 30-m depth dive, three hours after a normal breakfast and (B) a dive to the same depth, but after following a diet and fasting overnight. Each test consisted of 3 apnea phases: descent, static and ascent whose durations were measured by a standard chronometer. An impedance cardiograph, housed in an underwater torch, provided data on trans-thoracic fluid index (TFI), stroke volume (SV), heart rate (HR) and cardiac output (CO). Mean blood pressure (MBP), arterial O2 saturation (SaO2), blood glucose (Glu) and blood lactate (BLa) were also collected. In condition B, duration of the static phase of the dive was longer than A (37.8 ± 7.4 vs. 27.3 ± 8.4 s respectively, P fasting was lower than breakfast one (-2.6 ± 5.1 vs. 5.7 ± 7.6 ml, P fasting was lower than the same phase after breakfast (-0.4 ± 0.5 vs. 0.4 ± 0.5 L · min(-1) respectively, P fasting, SaO2 was higher than A (92.0 ± 2.7 vs. 89.4 ± 2.9 % respectively, P < 0.05) and BLa was lower in the same comparison (4.2 ± 0.7 vs. 5.3 ± 1.1 mmol∙L(-1), P < 0.05). An adequate balance between metabolic and splancnic status may improve the diving response during a dive at a depth of 30 m, in safe conditions for the athlete's health.

  8. Pre-dive Whole-Body Vibration Better Reduces Decompression-Induced Vascular Gas Emboli than Oxygenation or a Combination of Both

    Science.gov (United States)

    Balestra, Costantino; Theunissen, Sigrid; Papadopoulou, Virginie; Le Mener, Cedric; Germonpré, Peter; Guerrero, François; Lafère, Pierre

    2016-01-01

    Purpose: Since non-provocative dive profiles are no guarantor of protection against decompression sickness, novel means including pre-dive “preconditioning” interventions, are proposed for its prevention. This study investigated and compared the effect of pre-dive oxygenation, pre-dive whole body vibration or a combination of both on post-dive bubble formation. Methods: Six healthy volunteers performed 6 no-decompression dives each, to a depth of 33 mfw for 20 min (3 control dives without preconditioning and 1 of each preconditioning protocol) with a minimum interval of 1 week between each dive. Post-dive bubbles were counted in the precordium by two-dimensional echocardiography, 30 and 90 min after the dive, with and without knee flexing. Each diver served as his own control. Results: Vascular gas emboli (VGE) were systematically observed before and after knee flexing at each post-dive measurement. Compared to the control dives, we observed a decrease in VGE count of 23.8 ± 7.4% after oxygen breathing (p < 0.05), 84.1 ± 5.6% after vibration (p < 0.001), and 55.1 ± 9.6% after vibration combined with oxygen (p < 0.001). The difference between all preconditioning methods was statistically significant. Conclusions: The precise mechanism that induces the decrease in post-dive VGE and thus makes the diver more resistant to decompression stress is still not known. However, it seems that a pre-dive mechanical reduction of existing gas nuclei might best explain the beneficial effects of this strategy. The apparent non-synergic effect of oxygen and vibration has probably to be understood because of different mechanisms involved. PMID:27965591

  9. Judging complex movement performances for excellence: a principal components analysis-based technique applied to competitive diving.

    Science.gov (United States)

    Young, Cole; Reinkensmeyer, David J

    2014-08-01

    Athletes rely on subjective assessment of complex movements from coaches and judges to improve their motor skills. In some sports, such as diving, snowboard half pipe, gymnastics, and figure skating, subjective scoring forms the basis for competition. It is currently unclear whether this scoring process can be mathematically modeled; doing so could provide insight into what motor skill is. Principal components analysis has been proposed as a motion analysis method for identifying fundamental units of coordination. We used PCA to analyze movement quality of dives taken from USA Diving's 2009 World Team Selection Camp, first identifying eigenpostures associated with dives, and then using the eigenpostures and their temporal weighting coefficients, as well as elements commonly assumed to affect scoring - gross body path, splash area, and board tip motion - to identify eigendives. Within this eigendive space we predicted actual judges' scores using linear regression. This technique rated dives with accuracy comparable to the human judges. The temporal weighting of the eigenpostures, body center path, splash area, and board tip motion affected the score, but not the eigenpostures themselves. These results illustrate that (1) subjective scoring in a competitive diving event can be mathematically modeled; (2) the elements commonly assumed to affect dive scoring actually do affect scoring (3) skill in elite diving is more associated with the gross body path and the effect of the movement on the board and water than the units of coordination that PCA extracts, which might reflect the high level of technique these divers had achieved. We also illustrate how eigendives can be used to produce dive animations that an observer can distort continuously from poor to excellent, which is a novel approach to performance visualization. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. Buoyancy under control: underwater locomotor performance in a deep diving seabird suggests respiratory strategies for reducing foraging effort.

    Directory of Open Access Journals (Sweden)

    Timothée R Cook

    Full Text Available BACKGROUND: Because they have air stored in many body compartments, diving seabirds are expected to exhibit efficient behavioural strategies for reducing costs related to buoyancy control. We study the underwater locomotor activity of a deep-diving species from the Cormorant family (Kerguelen shag and report locomotor adjustments to the change of buoyancy with depth. METHODOLOGY/PRINCIPAL FINDINGS: Using accelerometers, we show that during both the descent and ascent phases of dives, shags modelled their acceleration and stroking activity on the natural variation of buoyancy with depth. For example, during the descent phase, birds increased swim speed with depth. But in parallel, and with a decay constant similar to the one in the equation explaining the decrease of buoyancy with depth, they decreased foot-stroke frequency exponentially, a behaviour that enables birds to reduce oxygen consumption. During ascent, birds also reduced locomotor cost by ascending passively. We considered the depth at which they started gliding as a proxy to their depth of neutral buoyancy. This depth increased with maximum dive depth. As an explanation for this, we propose that shags adjust their buoyancy to depth by varying the amount of respiratory air they dive with. CONCLUSIONS/SIGNIFICANCE: Calculations based on known values of stored body oxygen volumes and on deep-diving metabolic rates in avian divers suggest that the variations of volume of respiratory oxygen associated with a respiration mediated buoyancy control only influence aerobic dive duration moderately. Therefore, we propose that an advantage in cormorants--as in other families of diving seabirds--of respiratory air volume adjustment upon diving could be related less to increasing time of submergence, through an increased volume of body oxygen stores, than to reducing the locomotor costs of buoyancy control.

  11. Pressure Induced Changes in Adaptive Immune Function in Belugas (Delphinapterus leucas; implications for dive physiology and health

    Directory of Open Access Journals (Sweden)

    Laura A Thompson

    2016-09-01

    Full Text Available Increased pressure, associated with diving, can alter cell function through several mechanisms and has been shown to impact immune functions performed by peripheral blood mononuclear cells (PBMC in humans. While marine mammals possess specific adaptations which protect them from dive related injury, it is unknown how their immune system is adapted to the challenges associated with diving. The purpose of this study was to measure PBMC activation (IL2R expression and Concanavalin A induced lymphocyte proliferation (BrdU incorporation in belugas following in vitro pressure exposures during baseline, Out of Water Examination (OWE and capture/release conditions. Beluga blood samples (n=4 were obtained from animals at the Mystic Aquarium and from free ranging animals in Alaska (n=9. Human blood samples (n=4 (Biological Specialty Corporation were run for comparison. In vivo catecholamines and cortisol were measured in belugas to characterize the neuroendocrine response. Comparison of cellular responses between controls and pressure exposed cells, between conditions in belugas, between belugas and humans as well as between dive profiles, were run using mixed generalized linear models (α=0.05. Cortisol was significantly higher in wild belugas and OWE samples as compared with baseline for aquarium animals. Both IL2R expression and proliferation displayed significant pressure induced changes, and these responses varied between conditions in belugas. Both belugas and humans displayed increased IL2R expression, while lymphocyte proliferation decreased for aquarium animals and increased for humans and wild belugas. Results suggest beluga PBMC function is altered during diving and changes may represent dive adaptation as the response differs from humans, a non-dive adapted mammal. In addition, characteristics of a dive (i.e., duration, depth as well as neuroendocrine activity can alter the response of beluga cells, potentially impacting the ability of animals

  12. Extremely deep recreational dives: the risk for carbon dioxide (CO(2)) retention and high pressure neurological syndrome (HPNS).

    Science.gov (United States)

    Kot, Jacek

    2012-01-01

    Clear differences between professional and recreational deep diving are disappearing, at least when taking into account the types of breathing mixtures (oxygen, nitrox, heliox, and trimix) and range of dive parameters (depth and time). Training of recreational deep divers is conducted at depths of 120-150 metres and some divers dive to 180-200 metres using the same diving techniques. Extremely deep recreational divers go to depths of more than 200 metres, at which depths the physical and chemical properties of breathing gases create some physiological restrictions already known from professional deep diving. One risk is carbon dioxide retention due to limitation of lung ventilation caused by the high density of breathing gas mixture at great depths. This effect can be amplified by the introduction of the additional work of breathing if there is significant external resistance caused by a breathing device. The other risk for deep divers is High Pressure Neurological Syndrome (HPNS) caused by a direct compression effect, presumably on the lipid component of cell membranes of the central nervous system. In deep professional diving, divers use a mixture of helium and oxygen to decrease gas density, and nitrogen is used only in some cases for decreasing the signs and symptoms of HPNS. The same approach with decreasing the nitrogen content in the breathing mixture can also be observed nowadays in deep recreational diving. Moreover, in extremely deep professional diving, hydrogen has been used successfully both for decreasing the density of the breathing gas mixture and amelioration of HPNS signs and symptoms. It is fair to assume that the use of hydrogen will be soon "re-invented" by extremely deep recreational divers. So the scope of modern diving medicine for recreational divers should be expanded also to cover these problems, which previously were assigned exclusively to professional and military divers.

  13. A comparative evaluation of two decompression procedures for technical diving using inflammatory responses: compartmental versus ratio deco.

    Science.gov (United States)

    Spisni, Enzo; Marabotti, Claudio; De Fazio, Luigia; Valerii, Maria Chiara; Cavazza, Elena; Brambilla, Stefano; Hoxha, Klarida; L'Abbate, Antonio; Longobardi, Pasquale

    2017-03-01

    The aim of this study was to compare two decompression procedures commonly adopted by technical divers: the ZH-L16 algorithm modified by 30/85 gradient factors (compartmental decompression model, CDM) versus the 'ratio decompression strategy' (RDS). The comparison was based on an analysis of changes in diver circulating inflammatory profiles caused by decompression from a single dive. Fifty-one technical divers performed a single trimix dive to 50 metres' sea water (msw) for 25 minutes followed by enriched air (EAN50) and oxygen decompression. Twenty-three divers decompressed according to a CDM schedule and 28 divers decompressed according to a RDS schedule. Peripheral blood for detection of inflammatory markers was collected before and 90 min after diving. Venous gas emboli were measured 30 min after diving using 2D echocardiography. Matched groups of 23 recreational divers (dive to 30 msw; 25 min) and 25 swimmers were also enrolled as control groups to assess the effects of decompression from a standard air dive or of exercise alone on the inflammatory profile. Echocardiography at the single 30 min observation post dive showed no significant differences between the two decompression procedures. Divers adopting the RDS showed a worsening of post-dive inflammatory profile compared to the CDM group, with significant increases in circulating chemokines CCL2 (P = 0.001) and CCL5 (P = 0.006) levels. There was no increase in chemokines following the CDM decompression. The air scuba group also showed a statistically significant increase in CCL2 (P < 0.001) and CCL5 (P = 0.003) levels post dive. No cases of decompression sickness occurred. The ratio deco strategy did not confer any benefit in terms of bubbles but showed the disadvantage of increased decompression-associated secretion of inflammatory chemokines involved in the development of vascular damage.

  14. Diving physiology of seabirds and marine mammals: Relevance, challenges and some solutions for field studies.

    Science.gov (United States)

    Andrews, Russel D; Enstipp, Manfred R

    2016-12-01

    To fully understand how diving seabirds and marine mammals balance the potentially conflicting demands of holding their breath while living their lives underwater (and maintaining physiological homeostasis during exercise, feeding, growth, and reproduction), physiological studies must be conducted with animals in their natural environments. The purpose of this article is to review the importance of making physiological measurements on diving animals in field settings, while acknowledging the challenges and highlighting some solutions. The most extreme divers are great candidates for study, especially in a comparative and mechanistic context. However, physiological data are also required of a wide range of species for problems relating to other disciplines, in particular ecology and conservation biology. Physiological data help with understanding and predicting the outcomes of environmental change, and the direct impacts of anthropogenic activities. Methodological approaches that have facilitated the development of field-based diving physiology include the isolated diving hole protocol and the translocation paradigm, and while there are many techniques for remote observation, animal-borne biotelemetry, or "biologging", has been critical. We discuss issues related to the attachment of instruments, the retrieval of data and sensing of physiological variables, while also considering negative impacts of tagging. This is illustrated with examples from a variety of species, and an in-depth look at one of the best studied and most extreme divers, the emperor penguin (Aptenodytes forsteri). With a variety of approaches and high demand for data on the physiology of diving seabirds and marine mammals, the future of field studies is bright. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. Mobility, expansion and management of a multi-species scuba diving fishery in East Africa.

    Directory of Open Access Journals (Sweden)

    Hampus Eriksson

    Full Text Available BACKGROUND: Scuba diving fishing, predominantly targeting sea cucumbers, has been documented to occur in an uncontrolled manner in the Western Indian Ocean and in other tropical regions. Although this type of fishing generally indicates a destructive activity, little attention has been directed towards this category of fishery, a major knowledge gap and barrier to management. METHODOLOGY AND PRINCIPAL FINDINGS: With the aim to capture geographic scales, fishing processes and social aspects the scuba diving fishery that operate out of Zanzibar was studied using interviews, discussions, participant observations and catch monitoring. The diving fishery was resilient to resource declines and had expanded to new species, new depths and new fishing grounds, sometimes operating approximately 250 km away from Zanzibar at depths down to 50 meters, as a result of depleted easy-access stock. The diving operations were embedded in a regional and global trade network, and its actors operated in a roving manner on multiple spatial levels, taking advantage of unfair patron-client relationships and of the insufficient management in Zanzibar. CONCLUSIONS AND SIGNIFICANCE: This study illustrates that roving dynamics in fisheries, which have been predominantly addressed on a global scale, also take place at a considerably smaller spatial scale. Importantly, while proposed management of the sea cucumber fishery is often generic to a simplified fishery situation, this study illustrates a multifaceted fishery with diverse management requirements. The documented spatial scales and processes in the scuba diving fishery emphasize the need for increased regional governance partnerships to implement management that fit the spatial scales and processes of the operation.

  16. Neuroglobin of seals and whales: evidence for a divergent role in the diving brain.

    Science.gov (United States)

    Schneuer, M; Flachsbarth, S; Czech-Damal, N U; Folkow, L P; Siebert, U; Burmester, T

    2012-10-25

    Although many physiological adaptations of diving mammals have been reported, little is known about how their brains sustain the high demands for metabolic energy and thus O(2) when submerged. A recent study revealed in the deep-diving hooded seal (Cystophora cristata) a unique shift of the oxidative energy metabolism and neuroglobin, a respiratory protein that is involved in neuronal hypoxia tolerance, from neurons to astrocytes. Here we have investigated neuroglobin in another pinniped species, the harp seal (Pagophilus groenlandicus), and in two cetaceans, the harbor porpoise (Phocoena phocoena) and the minke whale (Balaenoptera acutorostrata). Neuroglobin sequences, expression levels and patterns were compared with those of terrestrial relatives, the ferret (Mustela putorius furo) and the cattle (Bos taurus), respectively. Neuroglobin sequences of whales and seals only differ in two or three amino acids from those of cattle and ferret, and are unlikely to confer functional differences, e.g. in O(2) affinity. Neuroglobin is expressed in the astrocytes also of P. groenlandicus, suggesting that the shift of neuroglobin and oxidative metabolism is a common adaptation in the brains of deep-diving phocid seals. In the cetacean brain neuroglobin resides in neurons, like in terrestrial mammals. However, neuroglobin mRNA expression levels were 4-15 times higher in the brains of harbor porpoises and minke whales than in terrestrial mammals or in seals. Thus neuroglobin appears to play a specific role in diving mammals, but seals and whales have evolved divergent strategies to cope with cerebral hypoxia. The specific function of neuroglobin that conveys hypoxia tolerance may either relate to oxygen supply or protection from reactive oxygen species. The different strategies in seals and whales resulted from a divergent evolution and an independent adaptation to diving. Copyright © 2012 IBRO. Published by Elsevier Ltd. All rights reserved.

  17. 'Sea legs': sharpened Romberg test after three days on a live-aboard dive boat.

    Science.gov (United States)

    Gibbs, Clinton R; Commons, Katherine H; Brown, Lawrence H; Blake, Denise F

    2010-12-01

    The sharpened Romberg test (SRT) is commonly used by diving and hyperbaric physicians as an indicator of neurological decompression illness (DCI). People who spend a prolonged time on a boat at sea experience impairment in their balance on returning to shore, a condition known as mal de debarquement ('sea legs'). This conditioning of the vestibular system to the rocking motion of a boat at sea may impact on the utility of the SRT in assessing a diver with potential DCI after a live-aboard dive trip. To assess the impact 'sea legs' has on the SRT after three days on a live-aboard dive trip. Thirty-nine staff and passengers of a three-day, live-aboard dive trip performed a SRT before and after their journey, with assessment of potential variables, including middle ear barotrauma, alcohol consumption, sea-sickness and occult DCI. There was no statistically significant impact on SRT performance, with 100% completion pre-trip and 35 out of 36 divers (97.2%) post-trip. There were trends towards more attempts being required and time needed for successful SRT post-trip, but these were not statistically significant. There was a small, but noteworthy incidence of middle-ear barotrauma, with seven people affected pre-trip, and 13 post-trip. There was a higher incidence in student divers. Middle-ear barotrauma did not appear to have a direct impact on SRT performance. There was no significant impact on SRT performance resulting from 'sea legs' after three days at sea. Recreational divers, especially dive students, have a substantial incidence of mild middle ear barotrauma.

  18. A prospective analysis of injury rates, patterns and causes in Cliff and Splash Diving.

    Science.gov (United States)

    Ernstbrunner, Lukas; Runer, Armin; Siegert, Paul; Ernstbrunner, Matthäus; Becker, Johannes; Freude, Thomas; Resch, Herbert; Moroder, Philipp

    2017-10-01

    Information about injuries and its differences in Cliff Diving (CD) and Splash Diving (SD) are unknown. It was the aim to analyse (1) injury rates, patterns and causes; (2) differences (in injuries) between both disciplines; and to (3) identify targets for future injury prevention interventions. From April to November 2013, 81 cliff and 51 splash divers were prospectively surveyed with an encrypted, monthly e-mail-based questionnaire. During a total of 7857h diving with an average diving height of 13 (±7)m, an overall injury rate of 7.9 injuries/1000h of sport exposure was reported. Cliff divers most commonly suffered from injuries of the foot and ankle (18%; n=24) and neck and cervical spine (14%; n=19). In SD, the lower limb (52%; n=43) and lower back (23%; n=19) were most frequently involved. In 79% (n=49) of the cases, the injury happened while entering the water. Cliff divers were in 52% (n=15) of the injuries in a feet-first and in 14% (n=4) in a head-first position. Splash divers were in 45% (n=9) of the injuries in a back- or buttocks-first position. Most of the injuries were bruises (47%; n=104) and muscle strains (13%; n=28). The injury risk during practice was significantly higher than in competition (11.3 vs. 4.5 injuries/1000h; OR 2.5; p=0.001). The injury risk of experts (15.4/1000h exposure) was significantly higher than in professionals (6.3/1000h exposure; OR 2.4; 95% CI, 3.3-1.9; pdiving height was significantly higher in professionals (19m±8 vs. 12m±6; pdiving conditions in practice to those in competition; dryland training courses; and instruction of non-professional divers to teach appropriate diving techniques. Copyright © 2017 Elsevier Ltd. All rights reserved.

  19. Grey Nurse Shark ( Carcharias taurus) Diving Tourism: Tourist Compliance and Shark Behaviour at Fish Rock, Australia

    Science.gov (United States)

    Smith, Kirby; Scarr, Mark; Scarpaci, Carol

    2010-11-01

    Humans can dive with critically endangered grey nurse sharks ( Carcharias taurus) along the east coast of Australia. This study investigated both compliance of tourist divers to a code of conduct and legislation and the behaviour of grey nurse sharks in the presence of divers. A total of 25 data collection dives were conducted from December 2008 to January 2009. Grey nurse shark and diver behaviour were documented using 2-min scan samples and continuous observation. The proportion of time spent observing human-shark interactions was 9.4% of total field time and mean human-shark interaction time was 15.0 min. Results were used to gauge the effectiveness of current management practices for the grey nurse shark dive industry at Fish Rock in New South Wales, Australia. Grey nurse shark dive tourists were compliant to stipulations in the code of conduct and legislation (compliance ranged from 88 to 100%). The research detailed factors that may promote compliance in wildlife tourism operations such as the clarity of the stipulations, locality of the target species and diver perceptions of sharks. Results indicated that grey nurse sharks spent the majority of their time milling (85%) followed by active swimming (15%). Milling behaviour significantly decreased in the presence of more than six divers. Distance between sharks and divers, interaction time and number of sharks were not significantly correlated with grey nurse shark school behaviour. Jaw gaping, rapid withdrawal and stiff or jerky movement were the specific behaviours of grey nurse sharks that occurred most frequently and were associated with distance between divers and sharks and the presence of six or more divers. Revision of the number of divers allowed per interaction with a school of grey nurse sharks and further research on the potential impacts that shark-diving tourism may pose to grey nurse sharks is recommended.

  20. Grey nurse shark (Carcharias taurus) diving tourism: Tourist compliance and shark behaviour at Fish Rock, Australia.

    Science.gov (United States)

    Smith, Kirby; Scarr, Mark; Scarpaci, Carol

    2010-11-01

    Humans can dive with critically endangered grey nurse sharks (Carcharias taurus) along the east coast of Australia. This study investigated both compliance of tourist divers to a code of conduct and legislation and the behaviour of grey nurse sharks in the presence of divers. A total of 25 data collection dives were conducted from December 2008 to January 2009. Grey nurse shark and diver behaviour were documented using 2-min scan samples and continuous observation. The proportion of time spent observing human-shark interactions was 9.4% of total field time and mean human-shark interaction time was 15.0 min. Results were used to gauge the effectiveness of current management practices for the grey nurse shark dive industry at Fish Rock in New South Wales, Australia. Grey nurse shark dive tourists were compliant to stipulations in the code of conduct and legislation (compliance ranged from 88 to 100%). The research detailed factors that may promote compliance in wildlife tourism operations such as the clarity of the stipulations, locality of the target species and diver perceptions of sharks. Results indicated that grey nurse sharks spent the majority of their time milling (85%) followed by active swimming (15%). Milling behaviour significantly decreased in the presence of more than six divers. Distance between sharks and divers, interaction time and number of sharks were not significantly correlated with grey nurse shark school behaviour. Jaw gaping, rapid withdrawal and stiff or jerky movement were the specific behaviours of grey nurse sharks that occurred most frequently and were associated with distance between divers and sharks and the presence of six or more divers. Revision of the number of divers allowed per interaction with a school of grey nurse sharks and further research on the potential impacts that shark-diving tourism may pose to grey nurse sharks is recommended.