Safety Priorities and Underestimations in Recreational Scuba Diving Operations: A European Study Supporting the Implementation of New Risk Management Programmes.

PubMed

Lucrezi, Serena; Egi, Salih Murat; Pieri, Massimo; Burman, Francois; Ozyigit, Tamer; Cialoni, Danilo; Thomas, Guy; Marroni, Alessandro; Saayman, Melville

2018-01-01

Introduction: Scuba diving is an important marine tourism sector, but requires proper safety standards to reduce the risks and increase accessibility to its market. To achieve safety goals, safety awareness and positive safety attitudes in recreational scuba diving operations are essential. However, there is no published research exclusively focusing on scuba divers' and dive centres' perceptions toward safety. This study assessed safety perceptions in recreational scuba diving operations, with the aim to inform and enhance safety and risk management programmes within the scuba diving tourism industry. Materials and Methods: Two structured questionnaire surveys were prepared by the organisation Divers Alert Network and administered online to scuba diving operators in Italy and scuba divers in Europe, using a mixture of convenience and snowball sampling. Questions in the survey included experience and safety offered at the dive centre; the buddy system; equipment and accessories for safe diving activities; safety issues in the certification of new scuba divers; incidents/accidents; and attitudes toward safety. Results: 91 scuba diving centres and 3,766 scuba divers participated in the study. Scuba divers gave importance to safety and the responsiveness of service providers, here represented by the dive centres. However, they underestimated the importance of a personal emergency action/assistance plan and, partly, of the buddy system alongside other safety procedures. Scuba divers agreed that some risks, such as those associated with running out of gas, deserve attention. Dive centres gave importance to aspects such as training and emergency action/assistance plans. However, they were limitedly involved in safety campaigning. Dive centres' perceptions of safety in part aligned with those of scuba divers, with some exceptions. Conclusion: Greater responsibility is required in raising awareness and educating scuba divers, through participation in prevention campaigns and training. The study supports the introduction of programmes aiming to create a culture of safety among dive centres and scuba divers. Two examples, which are described in this paper, include the Hazard Identification and Risk Assessment protocol for dive centres and scuba divers, and the Diving Safety Officer programme to create awareness, improve risk management, and mitigate health and safety risks.

Safety Priorities and Underestimations in Recreational Scuba Diving Operations: A European Study Supporting the Implementation of New Risk Management Programmes

PubMed Central

Lucrezi, Serena; Egi, Salih Murat; Pieri, Massimo; Burman, Francois; Ozyigit, Tamer; Cialoni, Danilo; Thomas, Guy; Marroni, Alessandro; Saayman, Melville

2018-01-01

Introduction: Scuba diving is an important marine tourism sector, but requires proper safety standards to reduce the risks and increase accessibility to its market. To achieve safety goals, safety awareness and positive safety attitudes in recreational scuba diving operations are essential. However, there is no published research exclusively focusing on scuba divers’ and dive centres’ perceptions toward safety. This study assessed safety perceptions in recreational scuba diving operations, with the aim to inform and enhance safety and risk management programmes within the scuba diving tourism industry. Materials and Methods: Two structured questionnaire surveys were prepared by the organisation Divers Alert Network and administered online to scuba diving operators in Italy and scuba divers in Europe, using a mixture of convenience and snowball sampling. Questions in the survey included experience and safety offered at the dive centre; the buddy system; equipment and accessories for safe diving activities; safety issues in the certification of new scuba divers; incidents/accidents; and attitudes toward safety. Results: 91 scuba diving centres and 3,766 scuba divers participated in the study. Scuba divers gave importance to safety and the responsiveness of service providers, here represented by the dive centres. However, they underestimated the importance of a personal emergency action/assistance plan and, partly, of the buddy system alongside other safety procedures. Scuba divers agreed that some risks, such as those associated with running out of gas, deserve attention. Dive centres gave importance to aspects such as training and emergency action/assistance plans. However, they were limitedly involved in safety campaigning. Dive centres’ perceptions of safety in part aligned with those of scuba divers, with some exceptions. Conclusion: Greater responsibility is required in raising awareness and educating scuba divers, through participation in prevention campaigns and training. The study supports the introduction of programmes aiming to create a culture of safety among dive centres and scuba divers. Two examples, which are described in this paper, include the Hazard Identification and Risk Assessment protocol for dive centres and scuba divers, and the Diving Safety Officer programme to create awareness, improve risk management, and mitigate health and safety risks. PMID:29628904

Do not fear the Framingham: Practical application to properly evaluate and modify cardiovascular risk in commercial divers.

PubMed

Suresh, Rahul; Pavela, James; Kus, Marcus S; Alleman, Tony; Sanders, Robert

2018-01-01

In April 2016 the Association of Diving Contractors International (ADCI) consensus guidelines began recommending annual cardiovascular risk stratification of commercial divers using the Framingham Risk Score (FRS). For those at elevated risk, further testing is recommended. This approach has raised concerns about potential operational and financial impacts. However, the prevalence of elevated cardiovascular risk and need for additional testing among commercial divers is not known. Clinical data required to calculate the FRS was abstracted for 190 commercial divers in two cohorts. Population demographics, FRS distribution, contributions of risk factors and effect of interventions on reducing risk-factor burden were assessed. Mean FRS score was 1.68 ± 6.35 points, with 13 divers (6.8%) at intermediate risk and none at high 10-year risk. In these 13 divers, the mean contributions to the FRS were from age (6.5 points), cholesterol (3.1 pts.), smoking (1.3 pts.), highdensity lipoprotein (1 pt.), and systolic blood pressure (0.8 pts). The youngest age group had a significantly higher modifiable risk core than the oldest age group (5.87 vs. 1.2 points, P ⟨ 0.001). All 13 intermediate risk divers could have been reclassified as low-risk with successful treatment of modifiable risk factors. The prevalence of elevated cardiovascular risk among commercial divers is low, and treatment of modifiable risk factors could reclassify those at intermediate risk to low risk. Therefore, FRS implementation coupled with intensive risk-reduction strategies for at risk-divers may help improve diver health and prolong the careers of divers while limiting the need for additional testing and adverse operational impact. Copyright© Undersea and Hyperbaric Medical Society.

46 CFR 71.50-27 - Alternative Hull Examination (AHE) program options: Divers or underwater remotely operated...

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 3 2010-10-01 2010-10-01 false Alternative Hull Examination (AHE) program options...-27 Alternative Hull Examination (AHE) program options: Divers or underwater remotely operated vehicle... operations; (2) Provide permanent hull markings, a temporary grid system of wires or cables spaced not more...

Recreational Diving Impacts on Coral Reefs and the Adoption of Environmentally Responsible Practices within the SCUBA Diving Industry

NASA Astrophysics Data System (ADS)

Roche, Ronan C.; Harvey, Chloe V.; Harvey, James J.; Kavanagh, Alan P.; McDonald, Meaghan; Stein-Rostaing, Vivienne R.; Turner, John R.

2016-07-01

Recreational diving on coral reefs is an activity that has experienced rapidly growing levels of popularity and participation. Despite providing economic activity for many developing coastal communities, the potential role of dive impacts in contributing to coral reef damage is a concern at heavily dived locations. Management measures to address this issue increasingly include the introduction of programmes designed to encourage environmentally responsible practices within the dive industry. We examined diver behaviour at several important coral reef dive locations within the Philippines and assessed how diver characteristics and dive operator compliance with an environmentally responsible diving programme, known as the Green Fins approach, affected reef contacts. The role of dive supervision was assessed by recording dive guide interventions underwater, and how this was affected by dive group size. Of the 100 recreational divers followed, 88 % made contact with the reef at least once per dive, with a mean (±SE) contact rate of 0.12 ± 0.01 per min. We found evidence that the ability of dive guides to intervene and correct diver behaviour in the event of a reef contact decreases with larger diver group sizes. Divers from operators with high levels of compliance with the Green Fins programme exhibited significantly lower reef contact rates than those from dive operators with low levels of compliance. The successful implementation of environmentally responsible diving programmes, which focus on influencing dive industry operations, can contribute to the management of human impacts on coral reefs.

29 CFR 1910.427 - Liveboating.

Code of Federal Regulations, 2010 CFR

2010-07-01

... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Commercial Diving Operations Specific Operations Procedures § 1910.427... of 220 fsw; (3) Using mixed gas at depths greater than 220 fsw; (4) In rough seas which significantly... while a diver is in the water. (5) A diver-carried reserve breathing gas supply shall be carried by each...

Recreational Diving Impacts on Coral Reefs and the Adoption of Environmentally Responsible Practices within the SCUBA Diving Industry.

PubMed

Roche, Ronan C; Harvey, Chloe V; Harvey, James J; Kavanagh, Alan P; McDonald, Meaghan; Stein-Rostaing, Vivienne R; Turner, John R

2016-07-01

Recreational diving on coral reefs is an activity that has experienced rapidly growing levels of popularity and participation. Despite providing economic activity for many developing coastal communities, the potential role of dive impacts in contributing to coral reef damage is a concern at heavily dived locations. Management measures to address this issue increasingly include the introduction of programmes designed to encourage environmentally responsible practices within the dive industry. We examined diver behaviour at several important coral reef dive locations within the Philippines and assessed how diver characteristics and dive operator compliance with an environmentally responsible diving programme, known as the Green Fins approach, affected reef contacts. The role of dive supervision was assessed by recording dive guide interventions underwater, and how this was affected by dive group size. Of the 100 recreational divers followed, 88 % made contact with the reef at least once per dive, with a mean (±SE) contact rate of 0.12 ± 0.01 per min. We found evidence that the ability of dive guides to intervene and correct diver behaviour in the event of a reef contact decreases with larger diver group sizes. Divers from operators with high levels of compliance with the Green Fins programme exhibited significantly lower reef contact rates than those from dive operators with low levels of compliance. The successful implementation of environmentally responsible diving programmes, which focus on influencing dive industry operations, can contribute to the management of human impacts on coral reefs.

New Polish occupational health and safety regulations for underwater works.

PubMed

Kot, Jacek; Sićko, Zdzisław

2007-01-01

In Poland, the new regulation of the Ministry of Health on Occupational Health for Underwater Works (dated 2007) pursuant to the Act on Underwater Works (dated 2003) has just been published. It is dedicated for commercial, non-military purposes. It defines health requirements for commercial divers and candidates for divers, medical assessment guide with a list of specific medical tests done on initial and periodical medical examination in order for a diver or a candidate for diver to be recognised fit for work, health surveillance during diving operations, compression and decompression procedures, list of content for medical equipment to be present at any diving place, formal qualifications for physicians conducting medical assessment of divers, requirements for certifications confirming the medical status of divers and candidates for divers. Decompression tables cover divings up to 120 meters of depth using compressed air, oxygen, nitrox and heliox as breathing mixtures. There are also decompression tables for repetitive diving, altitude diving and diving in the high-density waters (mud diving). It this paper, general description of health requirements for divers, as well as decompression tables that are included in the new Regulation on Occupational Health for Underwater Works are presented.

Experiments on the mechanism of underwater hearing.

PubMed

Pau, Hans Wilhelm; Warkentin, Mareike; Specht, Olaf; Krentz, Helga; Herrmann, Anne; Ehrt, Karsten

2011-12-01

The findings suggest that underwater sound perception is realized by the middle ear rather than by bone conduction, at least in shallow water conditions. To prove whether underwater sound perception is effected by bone conduction or by conduction via the middle ear. Five divers, breathing through snorkels, were tested in a swimming pool, to determine whether a sound was louder when the acoustic source placed was in front of the head in comparison with a lateral application facing the ear region. The second experiment investigated whether sound perception is influenced by ear protection plugs in underwater conditions. Also, the effect of a 5 mm thick neoprene hood was determined, with and without an additional perforation in the ear region. Sounds were louder when applied from a position laterally facing the ear, louder without than with a protection plug, louder without than with a neoprene hood on, and louder when the neoprene hood had a perforation in the region of the ear than with an intact hood.

Commercial diving fatalities.

PubMed

Bradley, M E

1984-08-01

The distributions of fatal diving accidents in commercial diver populations were examined in the Gulf of Mexico from 1968 to 1975 and in the British sector of the North Sea from 1971 to 1978. Influences and causes of death were analyzed by examining the interaction between host, environmental and agent factors. The interaction of host and environmental factors appeared to be the greatest contributing factor to diving fatalities among the estimated 900 commercial divers in the Gulf of Mexico and the 700 in the North Sea. The most significant host factors were level of experience and behavioral dysfunction. They are also the host characteristics most amenable to change through improved and more thorough training. The most significant environmental factors were equipment failure and supervisor/tender errors. These factors would be minimized by improved selection, maintenance and operation of equipment, together with improved operating and emergency diving procedures. In recent years there has been a significant downward trend in mortality rates in the commercial diver populations of this study due to improved diving techniques and operations. Further research is needed, however, on the cause(s) of diver unconsciousness and inexplicable actions that occur at depths below 91.44m (300 ft.).

CERC Field Research Facility Environmental Data Summary, 1977-79.

DTIC Science & Technology

1982-12-01

Motorola "Mini-Ranger," coupled to a Hewlett-Packard Mini-Computer and flatbed plotter. This positioning system was put together and operated by Prank... laminations within the core. While one diver collected the sample, the second diver recorded conditions on the bottom. This description included sediment

Advanced deep sea diving equipment

NASA Technical Reports Server (NTRS)

Danesi, W. A.

1972-01-01

Design requirements are generated for a deep sea heavy duty diving system to equip salvage divers with equipment and tools that permit work of the same quality and in times approaching that done on the surface. The system consists of a helmet, a recirculator for removing carbon dioxide, and the diver's dress. The diver controls the inlet flow by the recirculatory control valve and is able to change closed cycle operation to open cycle if malfunction occurs. Proper function of the scrubber in the recirculator minimizes temperature and humidity effects as it filters the returning air.

ROV's: The key is cost effectiveness

DOE Office of Scientific and Technical Information (OSTI.GOV)

Saunders, E.

1986-10-01

Although diver-support activities will continue to be required in terms of monitoring and assistance, low-cost, remotely operated vehicles (ROV's) will have an increasing presence in the oil industry and other fields provided there is ongoing improvement in management, preparation, and execution of work. Beyond the safety aspect, the key is cost effectiveness. It is the company's intention wherever possible, and within realistic constraints, to take the man out of the water either by direct ROV replacement of the diver or by assisting him. Shell's exploration and production operations are based in three main areas: the southern, central, and northern Northmore » Sea. These developed fields, which consist of 26 various structures (interconnected), are connected to the mainland by over 1,100 km of submarine pipeline. Maintenance and underwater engineering costs in northern operations alone exceed pounds40 million/year (about $60 million/year) where typical support is an estimated 700 ROV days/year. The utilization analysis indicates a major use in ''eyeball'' vehicles for diver monitoring, and a large percentage for pipeline survey with only a limited amount on structural work and other special applications. The ''Bondi initiative'' in the late 1970s was intended to remove the diver from the water by ROV replacement, but due to lack of development, the capability in many areas has not evolved.« less

Estimating the risk of a scuba diving fatality in Australia.

PubMed

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.

Optimizing Optics For Remotely Controlled Underwater Vehicles

NASA Astrophysics Data System (ADS)

Billet, A. B.

1984-09-01

The past decade has shown a dramatic increase in the use of unmanned tethered vehicles in worldwide marine fields. These vehicles are used for inspection, debris removal and object retrieval. With advanced robotic technology, remotely operated vehicles (ROVs) are now able to perform a variety of jobs previously accomplished only by divers. The ROVs can be used at greater depths and for riskier jobs, and safety to the diver is increased, freeing him for safer, more cost-effective tasks requiring human capabilities. Secondly, the ROV operation becomes more cost effective to use as work depth increases. At 1000 feet a diver's 10 minutes of work can cost over $100,000 including support personnel, while an ROV operational cost might be 1/20 of the diver cost per day, based on the condition that the cost for ROV operation does not change with depth, as it does for divers. In the ROV operation the television lens must be as good as the human eye, with better light gathering capability than the human eye. The RCV-150 system is an example of these advanced technology vehicles. With the requirements of manueuverability and unusual inspection, a responsive, high performance, compact vehicle was developed. The RCV-150 viewing subsystem consists of a television camera, lights, and topside monitors. The vehicle uses a low light level Newvicon television camera. The camera is equipped with a power-down iris that closes for burn protection when the power is off. The camera can pan f 50 degrees and tilt f 85 degrees on command from the surface. Four independently controlled 250 watt quartz halogen flood lamps illuminate the viewing area as required; in addition, two 250 watt spotlights are fitted. A controlled nine inch CRT monitor provides real time camera pictures for the operator. The RCV-150 vehicle component system consists of the vehicle structure, the vehicle electronics, and hydraulic system which powers the thruster assemblies and the manipulator. For this vehicle, a light weight, high response hydraulic system was developed in a very small package.

A subjective evaluation of a drinking system for saturation divers.

PubMed

Hope, Arvid; Brekken, Rudolf

2010-03-01

Studies have shown that divers may lose large volumes of body fluids in hot water suit (HWS) dives lasting for four hours or longer, and that this dehydration is mainly caused by sweating. Body fluid balance may be impaired and the diver's alertness and power of judgement could be influenced by such imbalance. The main objective of the present study was to obtain a subjective judgement of a drinking system for divers (DSFD) and to obtain information related to body fluid loss during long saturation lock-out dives. Via a suction pipe imbedded in the microphone unit in the oronasal mask, the DSFD makes it possible for the diver to drink while in the water. Ten divers tested the drinking system during 12 saturation lock-out dives lasting on average for 5.5 h. A questionnaire was answered after each dive. The divers drank 21 times (range 5-30 times) during the dives, and the average drinking volume was 1.4 litre (range 1.0-1.5 litre) but only drank 0.04 litre (range 0-0.3 litre) in the bell after diving. The system was easy to operate and preparation and clothing did not cause any delay. The suction pipe did not intrude and the microphone performed excellently. The work in water was not hindered by DSFD and all divers were very satisfied with the drinking system. It was obvious that the need for fluid intake after a dive with DSFD was markedly reduced; another good indication of maintained body fluid balance.

Exercising divers' thermal protection as a function of water temperature.

PubMed

Pendergast, David R; Mollendorf, Joseph

2011-01-01

Physiological adjustments and passive thermal insulation are not sufficient to protect divers in the cold and warm waters experienced by sport, professional and military divers. In a previous study of resting subjects, divers were protected by actively heated/cooled water that perfused a six-zone (head, torso, arms, hands, legs and feet) tube suit. Subsequently a self-contained diver thermal protection system (DTPS) was developed and used in this study to test male divers (n = 8) wearing a 6-mm foam neoprene wetsuit in water temperatures (T(W)) of 10 degrees C-39 degrees C at 4 feet in depth. The DTPS is a scuba backpack containing five thermoelectric devices that heat/cool water to 30 degrees C, six pumps that circulate the water through a six-zone tube suit via two manifolds, and an electronic controller. Skin temperatures (T(S), n = 17) and core temperature (T(C), capsule) were measured. The DTPS and each zone of the tube suit were also instrumented. Divers were tested with the DTPS operational (protected) and turned off (unprotected) for 90 minutes. In the unprotected condition, T(S) decreased and approached T(W), while T(C) trended to decrease over the exposure time. Mean T(S) as a function of T(W) was T(S) = 0.44 T(W) + 21.23 degrees C while unprotected, but T(S) = 0.19 T(W) + 27.1 degrees C when the diver was protected. The average total heating/cooling power required to protect the diver was 166 +/- 78W, 86 +/- 95W, 9 +/- 75W, 72 +/- 45W, 135 +/- 73W, 279 +/- 87W and 336 +/- 95W at 10, 15, 20, 25, 30, 35 and 39 degrees C water temperatures, respectively. This power requirement was nominally split 4%, 22%, 22%, 14%, 25% and 13% for head, torso, arms, hands, legs and feet, respectively. While unprotected, divers T(S) and T(C) did not remain within acceptable limits in T(W) below 25 degrees C or above 30 degrees C. When using the DTPS, however, they did remain within acceptable limits, and the divers reported they were comfortable.

Accident rates at a busy diving centre.

PubMed

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 time off work. Many of these were secondary to lifting and carrying heavy diving equipment, particularly dive tanks. This indicates an area where improved practices by staff could be achieved. We believe these injury data are robust and provide an accurate picture of a single, mainstream, international tourism diving centre in temperate waters, and indicate a low rate of injury, comparable to the international literature.

Estimation of peacock bass (Cichla spp.) mortality rate during catch-release fishing employing different post-capture procedures.

PubMed

Barroco, L S A; Freitas, C E C; Lima, Á C

2018-05-01

The effect of catch-and-release fishing on the survival of peacock bass (Cichla spp.) was evaluated by comparing two types of artificial bait (jig and shallow-diver plugs) and two types of post-catch confinement. Two experiments were conducted during the periods January-February and October-November 2012 in the Unini River, a right-bank tributary of the Negro River. In total, 191 peacock bass were captured. Both groups of fish were subjected to experimental confinement (collective and individual) for three days. Additionally, 11 fish were tagged with radio transmitters for telemetry monitoring. Mortality rate was estimated as the percentage of dead individuals for each type of bait and confinement. For peacock bass caught with jig baits, mortality was zero. The corresponding figure for shallow-diver bait was 1.66% for fish in collective containment, 18.18% for fish monitored by telemetry and 0% for individuals confined individually. Our results show low post-release mortality rates for peacock bass. Furthermore, neither the type of confinement nor the type of bait had a statistically significant influence on mortality rates. While future studies could include other factors in the analysis, our results show that catch-and-release fishing results in low mortality rates.

Grey nurse shark (Carcharias taurus) diving tourism: Tourist compliance and shark behaviour at Fish Rock, Australia.

PubMed

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.

Grey Nurse Shark ( Carcharias taurus) Diving Tourism: Tourist Compliance and Shark Behaviour at Fish Rock, Australia

NASA Astrophysics Data System (ADS)

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.

Orion's Neutral Buoyancy Lab (NBL) Activities

NASA Image and Video Library

2016-09-21

U.S. Navy divers are training in the Neutral Buoyancy Laboratory at NASA’s Johnson Space Center in Houston. Navy divers, Air Force pararescuemen and Coast Guard rescue swimmers practice Orion underway recovery techniques using a test version of the Orion spacecraft. Training will help the team prepare for Underway Recovery Test 5 for Exploration Mission 1 aboard the USS San Diego in the Pacific Ocean off the coast of California in October. The Ground Systems Development and Operations Program, along with the U.S. Navy and Lockheed Martin, are preparing the recovery team, hardware and operations to support EM-1 recovery.

Ketogenic diet for high partial pressure oxygen diving.

PubMed

Valadao, Jason M; Vigilante, John A; DiGeorge, Nicholas W; O'Connor, Sunila E; Bear, Alexandria; Kenyon, Jeffrey; Annis, Heather; Dituri, Joseph; Dituri, Amy E; Whelan, Harry T

2014-01-01

A ketogenic diet (KD) may decrease central nervous system oxygen toxicity symptoms in divers, and in view of this implication a feasibility/ toxicity pilot study was performed to demonstrate tolerance of KD while performing normal diving profiles. The exact mechanism of neuroprotection from the KD remains unknown; however, evidence to support the efficacy of the KD in reducing seizures is present in epilepsy and oxygen toxicity studies, and may provide valuable insight in diving activities. Three divers (two males and one female ages 32-45 with a history of deep diving and high pO2 exposure) on the KD made dives to varying depths in Hawaii using fully closed-circuit MK-15 and Inspiration rebreathers. These rebreathers have an electronically controlled set point, allowing the divers to monitor and control the oxygen level in the breathing loop, which can be varied manually by the divers. Oxygen level was varied during descent, bottom depth and ascent (decompression). Divers fasted for 12-18 hours before diet initiation. The ketosis level was verified by urinating on a Ketostix (reagent strips for urinalysis). Ketosis was achieved and was easily monitored with Ketostix in the simulated operational environment. The KD did not interfere with the diving mission; no seizure activity or signs or symptoms of CNS toxicity were observed, and there were no adverse effects noted by the divers while on the KD.

Smith and Navistar Electric and Plug-In Hybrid Vehicle Testing |

Science.gov Websites

plug-in hybrid electric vehicles operated by a variety of companies in diverse climates across the plug-in hybrid electric drive systems in medium-duty trucks operating in fleet service across the nation. U.S. companies agreeing to participate in this evaluation project received funding from the

Standards on medical fitness examinations for Navy divers.

PubMed

Weiss, Michael

2003-01-01

The German Navy employs approximately 480 divers in their primary and secondary role. Before entering diving training, every diver has to pass an intensive physical examination programme at the German Naval Medical Institute (NMI) in Kiel-Kronshagen. Annual follow-ups ensure the currency of the medical findings. Criteria of medical fitness for diving reflect industrial medical standards for hyperbaric workers as well as the general medical guidelines for NATO divers. A diving examination consists of the individual medical history, a physical examination including the neurological status and the assessment of the cardiovascular fitness by ECG and bicycle ergometry. The respiratory system is screened by regular chest x-rays and spirometry or body plethysmography. Blood and urine samples are taken to look for abnormal haematological and metabolic conditions as well as disorders of the genito-urinary system. In order to determine visual fitness, diver's visual acuity, colour vision and stereopsis as well as eye fundi are examined by an eye specialist. Also the ENT examination involves a speciality consultant and consists of audiometry, inspection of the external ear and tympanic membrane and functional tests. To ensure a high standard of dental fitness, screening by a dental officer is part of the annual check-up. Every routine diving medical examination at the NMI includes a pressure test in the hyperbaric chamber. Divers who use nitrox or oxygen-rebreather devices have to pass successfully an oxygen tolerance test under hyperbaric conditions. The annual routine diving medical examination contributes to minimize the risk of accidents in military diving operations.

Diver Operated Tools and Applications for Underwater Construction

DTIC Science & Technology

1987-01-01

subsurface construction. rhe list is by no means exhaustive and new 3 methods and requirements continue to evolve. * 8 I NCUAPTUN TIM DIVINO OPMATIONS...length suit that permitted the exhaust air to escape under the hem. By 1840, Siebe made a full length waterproof suit and added an exhaust valve to...The open circuit scuba takes 3 air from the supply tank, is inhaled by th& diver, and then exhausted directly to the surrounding water. 3 The basic

Odyne Plug-In Hybrid Electric Utility Truck Testing | Transportation

Science.gov Websites

Research | NREL Odyne Plug-In Hybrid Electric Utility Truck Evaluation Odyne Plug-In Hybrid data on plug-in hybrid electric utility trucks operated by a variety of companies. Photo courtesy of Odyne, NREL NREL is evaluating the in-service performance of about 120 plug-in hybrid electric utility

Sharks and people: insight into the global practices of tourism operators and their attitudes to shark behaviour.

PubMed

Richards, Kirsty; O'Leary, Bethan C; Roberts, Callum M; Ormond, Rupert; Gore, Mauvis; Hawkins, Julie P

2015-02-15

Shark tourism is a popular but controversial activity. We obtained insights into this industry via a global e-mailed questionnaire completed by 45 diving/snorkelling operators who advertised shark experiences (shark operators) and 49 who did not (non-shark operators). 42% of shark operators used an attractant to lure sharks and 93% stated they had a formal code of conduct which 86% enforced "very strictly". While sharks were reported to normally ignore people, 9 operators had experienced troublesome behaviour from them. Whilst our research corroborates previous studies indicating minimal risk to humans from most shark encounters, a precautionary approach to provisioning is required to avoid potential ecological and societal effects of shark tourism. Codes of conduct should always stipulate acceptable diver behaviour and appropriate diver numbers and shark operators should have a moral responsibility to educate their customers about the need for shark conservation. Copyright © 2014 Elsevier Ltd. All rights reserved.

Protection Against Hearing Loss in General Aviation Operations, Phase II

NASA Technical Reports Server (NTRS)

Parker, J. F., Jr.

1972-01-01

An inflight evaluation of four aural protectors is presented. The hearing protection devices studied were ear muffs, plastic ear plugs, rubber ear plugs, and wax ear plugs. It is concluded that ear plugs are satisfactory for providing adequate sound attenuation in general aviation aircraft. However, two problems were found in the use of ear plugs; comfort and interference with cabin communications.

Rotating arc spark plug

DOEpatents

Whealton, John H.; Tsai, Chin-Chi

2003-05-27

A spark plug device includes a structure for modification of an arc, the modification including arc rotation. The spark plug can be used in a combustion engine to reduce emissions and/or improve fuel economy. A method for operating a spark plug and a combustion engine having the spark plug device includes the step of modifying an arc, the modifying including rotating the arc.

Evaluation of Head Mounted and Head Down Information Displays During Simulated Mine-Countermeasures Dives to 42 msw

DTIC Science & Technology

2008-04-01

visualisation tête basse (VTB) ou d’un visiocasque pour l’exécution de leurs tâches courantes sous l’eau. Neuf plongeurs de lutte contre les mines ont...existe peu d’information empirique sur l’aptitude des plongeurs à utiliser un dispositif multifonction de visualisation tête basse (VTB) ou d’un...experiment, the diver was also linked to the researchers and operations crew via audio communications. 11 Display Screen Chamber Laptop Diver

Orion Neutral Buoyancy Lab (NBL) Activities

NASA Image and Video Library

2016-09-20

NASA astronaut Dan Burbank speaks to a group of U.S. Navy divers at the Neutral Buoyancy Laboratory (NBL) at the agency’s Johnson Space Center in Houston. Navy divers, Air Force pararescuemen and Coast Guard rescue swimmers are preparing to practice Orion underway recovery techniques with a test version of the Orion spacecraft. Training will help the team prepare for Underway Recovery Test 5 for Exploration Mission 1 aboard the USS San Diego in the Pacific Ocean off the coast of California in October. The Ground Systems Development and Operations Program, along with the U.S. Navy and Lockheed Martin, are preparing the recovery team, hardware and operations to support EM-1 recovery.

Nuclear reactor apparatus

DOEpatents

Wade, Elman E.

1978-01-01

A lifting, rotating and sealing apparatus for nuclear reactors utilizing rotating plugs above the nuclear reactor core. This apparatus permits rotation of the plugs to provide under the plug refueling of a nuclear core. It also provides a means by which positive top core holddown can be utilized. Both of these operations are accomplished by means of the apparatus lifting the top core holddown structure off the nuclear core while stationary, and maintaining this structure in its elevated position during plug rotation. During both of these operations, the interface between the rotating member and its supporting member is sealingly maintained.

40 CFR 146.92 - Injection well plugging.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 40 Protection of Environment 24 2012-07-01 2012-07-01 false Injection well plugging. 146.92... to Class VI Wells § 146.92 Injection well plugging. (a) Prior to the well plugging, the owner or operator must flush each Class VI injection well with a buffer fluid, determine bottomhole reservoir...

Playing with Plug-ins

ERIC Educational Resources Information Center

Thompson, Douglas E.

2013-01-01

In today's complex music software packages, many features can remain unexplored and unused. Software plug-ins--available in most every music software package, yet easily overlooked in the software's basic operations--are one such feature. In this article, I introduce readers to plug-ins and offer tips for purchasing plug-ins I have…

40 CFR 144.62 - Cost estimate for plugging and abandonment.

Code of Federal Regulations, 2010 CFR

2010-07-01

... 40 Protection of Environment 22 2010-07-01 2010-07-01 false Cost estimate for plugging and... Waste Injection Wells § 144.62 Cost estimate for plugging and abandonment. (a) The owner or operator must prepare a written estimate, in current dollars, of the cost of plugging the injection well in...

Versatile Friction Stir Welding/Friction Plug Welding System

NASA Technical Reports Server (NTRS)

Carter, Robert

2006-01-01

A proposed system of tooling, machinery, and control equipment would be capable of performing any of several friction stir welding (FSW) and friction plug welding (FPW) operations. These operations would include the following: Basic FSW; FSW with automated manipulation of the length of the pin tool in real time [the so-called auto-adjustable pin-tool (APT) capability]; Self-reacting FSW (SRFSW); SR-FSW with APT capability and/or real-time adjustment of the distance between the front and back shoulders; and Friction plug welding (FPW) [more specifically, friction push plug welding] or friction pull plug welding (FPPW) to close out the keyhole of, or to repair, an FSW or SR-FSW weld. Prior FSW and FPW systems have been capable of performing one or two of these operations, but none has thus far been capable of performing all of them. The proposed system would include a common tool that would have APT capability for both basic FSW and SR-FSW. Such a tool was described in Tool for Two Types of Friction Stir Welding (MFS- 31647-1), NASA Tech Briefs, Vol. 30, No. 10 (October 2006), page 70. Going beyond what was reported in the cited previous article, the common tool could be used in conjunction with a plug welding head to perform FPW or FPPW. Alternatively, the plug welding head could be integrated, along with the common tool, into a FSW head that would be capable of all of the aforementioned FSW and FPW operations. Any FSW or FPW operation could be performed under any combination of position and/or force control.

40 CFR 146.92 - Injection well plugging.

Code of Federal Regulations, 2011 CFR

2011-07-01

... operator must flush each Class VI injection well with a buffer fluid, determine bottomhole reservoir... for determining bottomhole reservoir pressure; (2) Appropriate testing methods to ensure external... accurate by the owner or operator and by the person who performed the plugging operation (if other than the...

Scientific Diving

EPA Pesticide Factsheets

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.

29 CFR 1910.424 - SCUBA diving.

Code of Federal Regulations, 2010 CFR

2010-07-01

... OCCUPATIONAL SAFETY AND HEALTH STANDARDS Commercial Diving Operations Specific Operations Procedures § 1910.424... physically confining spaces. (4) A diver-carried reserve breathing gas supply shall be provided for each... breathing gas supply shall be in the closed position prior to the dive. ...

Aeroacoustics of contoured and solid/porous conical plug-nozzle supersonic jet flows

NASA Technical Reports Server (NTRS)

Dosanjh, D. S.; Das, I. S.

1985-01-01

The acoustic far field, the shock-associated noise and characteristics of the repetitive shock structure of supersonic jet flows issuing from a contoured plug-nozzle and uncontoured plug-nozzle having a short conical plug of either a solid or a combination of solid/porous surface with pointed termination operated at a range of supercritical pressure are reported. The contoured and the uncontoured plug-nozzles had the same throat area and the same annular-radius ratio.

Assessing the Social Carrying Capacity of Diving Sites in Mabul Island, Malaysia

NASA Astrophysics Data System (ADS)

Zhang, Liye; Chung, ShanShan

2015-12-01

This study has explored social carrying capacity of an underwater environment based on divers' perceived crowding. Two dimensions were assessed, the number of divers seen and the proximity of diver. Data were obtained from a survey of 132 divers dived in Mabul Island, Malaysia during 2013-2014. Photographs depicting four levels of diver number and four levels of diver proximity in different combinations were shown to the respondents for assessing their acceptability. Between the two variables, the "number of divers" was the most influential factor for divers' perceived crowding. Divers would start to feel unacceptably crowded if 8-9 divers were visible to them at one time. Based on this, it is likely that the use level of diving sites in Mabul Island has already exceeded its social carrying capacity. Implications for future research and diving tourism management for Mabul Island are also discussed in the paper.

Assessing the Social Carrying Capacity of Diving Sites in Mabul Island, Malaysia.

PubMed

Zhang, Liye; Chung, ShanShan

2015-12-01

This study has explored social carrying capacity of an underwater environment based on divers' perceived crowding. Two dimensions were assessed, the number of divers seen and the proximity of diver. Data were obtained from a survey of 132 divers dived in Mabul Island, Malaysia during 2013-2014. Photographs depicting four levels of diver number and four levels of diver proximity in different combinations were shown to the respondents for assessing their acceptability. Between the two variables, the "number of divers" was the most influential factor for divers' perceived crowding. Divers would start to feel unacceptably crowded if 8-9 divers were visible to them at one time. Based on this, it is likely that the use level of diving sites in Mabul Island has already exceeded its social carrying capacity. Implications for future research and diving tourism management for Mabul Island are also discussed in the paper.

[Dampness in an electric plug as a cause of electricity failure in an operation theatre].

PubMed

Andersen, C; Pold, R; Nielsen, H D

2000-02-07

Two cases of electricity failure in an operation theatre during open heart surgery are discussed. The fuse for the patient monitor, ventilator, surgery instruments and heart lung machine was blown. Short-circuit was established because of humidity in the plug of the heater for fluid and blood. We recommend sealed or founded plugs and that anaesthesia equipment should not be used as an electrical supply for other electronic apparatus.

Innovations for ISS Plug-In Plan (IPiP) Operations

NASA Technical Reports Server (NTRS)

Moore, Kevin D.

2013-01-01

Limited resources and increasing requirements will continue to influence decisions on ISS. The ISS Plug-In Plan (IPiP) supports power and data for utilization, systems, and daily operations through the Electrical Power System (EPS) Secondary Power/Data Subsystem. Given the fluid launch schedule, the focus of the Plug-In Plan has evolved to anticipate future requirements by judicious development and delivery of power supplies, power strips, Alternating Current (AC) power inverters, along with innovative deployment strategies. A partnership of ISS Program Office, Engineering Directorate, Mission Operations, and International Partners poses unique solutions with existing on-board equipment and resources.

Method for preventing plugging in the pyrolysis of agglomerative coals

DOEpatents

Green, Norman W.

1979-01-23

To prevent plugging in a pyrolysis operation where an agglomerative coal in a nondeleteriously reactive carrier gas is injected as a turbulent jet from an opening into an elongate pyrolysis reactor, the coal is comminuted to a size where the particles under operating conditions will detackify prior to contact with internal reactor surfaces while a secondary flow of fluid is introduced along the peripheral inner surface of the reactor to prevent backflow of the coal particles. The pyrolysis operation is depicted by two equations which enable preselection of conditions which insure prevention of reactor plugging.

36 CFR 3.8 - What vessel operations are prohibited?

Code of Federal Regulations, 2010 CFR

2010-07-01

..., except at a launch site designated by the superintendent. (3) Operating a power-driven vessel on waters... power-driven or sailing vessel within 100 feet of a diver's flag except a vessel in support of dive... paragraph. (5) Unless a designated area is marked otherwise, operating a power-driven or sailing vessel...

The induction and compensation of asymmetric eye movements following unilateral blockage of a horizontal semicircular canal in the rabbit.

PubMed

Barmack, N H; Pettorossi, V E

1988-08-01

The influence of unilateral plugs of the left horizontal semicircular canal (LHC plugs) of rabbits on the development and compensation of asymmetric eye movements evoked by horizontal vestibular stimulation was studied. LHC plugs caused an immediate reduction of 50-65% in the gain of the horizontal vestibuloocular reflex (HVOR). This reduction in gain was achieved without altering the symmetry of the HVOR, and was accompanied by a change in the axial alignment of eye movements evoked by vestibular stimulation about the vertical (HVOR) and longitudinal (VVOR) axes. Postoperative asymmetry of eye movements developed 12-48 hr after the plugging operation. The development of asymmetry was reduced if the rabbit was restrained for 24 hr, thereby minimizing vestibular stimulation following the plugging operation. Over a 3-4 week period, the normal symmetry of eye movements was restored and the axial alignments of the HVOR and VVOR returned to the preoperative values. The gain of the HVOR did not recover. The horizontal cervicoocular reflex (HCOR) was examined before the plugging operation and after compensation of asymmetry was complete. The gain and phase of the HCOR were not altered. A relatively simple set of explanations at a cellular level is proposed to account for the induction and compensation of asymmetric eye movements following a unilateral plug of the horizontal semicircular canal.

Research on ultrasonic excitation for the removal of drilling fluid plug, paraffin deposition plug, polymer plug and inorganic scale plug for near-well ultrasonic processing technology.

PubMed

Wang, Zhenjun; Zeng, Jing; Song, Hao; Li, Feng

2017-05-01

Near-well ultrasonic processing technology attracts more attention due to its simple operation, high adaptability, low cost and no pollution to the formation. Although this technology has been investigated in detail through laboratory experiments and field tests, systematic and intensive researches are absent for certain major aspects, such as whether ultrasonic excitation is better than chemical agent for any plugs removal; whether ultrasound-chemical combination plug removal technology has the best plugs removal effect. In this paper, the comparison of removing drilling fluid plug, paraffin deposition plug, polymer plug and inorganic scale plug using ultrasonic excitation, chemical agent and ultrasound-chemical combination plug removal technology is investigated. Results show that the initial core permeability and ultrasonic frequency play a significant role in plug removal. Ultrasonic excitation and chemical agent have different impact on different plugs. The comparison results show that the effect of removing any plugs using ultrasound-chemicals composite plug removal technology is obviously better than that using ultrasonic excitation or chemical agent alone. Such conclusion proves that ultrasonic excitation and chemical agent can cause synergetic effects. Copyright © 2016 Elsevier B.V. All rights reserved.

Porous plug for Gravity Probe B

NASA Astrophysics Data System (ADS)

Wang, Suwen; Everitt, C. W. Francis; Frank, David J.; Lipa, John A.; Muhlfelder, Barry F.

2015-11-01

The confinement of superfluid helium for a Dewar in space poses a unique challenge due to its propensity to minimize thermal gradients by essentially viscous-free counterflow. This poses the risk of losing liquid through a vent pipe, reducing the efficiency of the cooling process. To confine the liquid helium in the Gravity Probe B (GP-B) flight Dewar, a porous plug technique was invented at Stanford University. Here, we review the history of the porous plug and its development, and describe the physics underlying its operation. We summarize a few missions that employed porous plugs, some of which preceded the launch of GP-B. The design, manufacture and flight performance of the GP-B plug are described, and its use resulted in the successful operation of the 2441 l flight Dewar on-orbit for 17.3 months.

30 CFR 250.402 - When and how must I secure a well?

Code of Federal Regulations, 2011 CFR

2011-07-01

..., DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Drilling Operations General Requirements § 250.402 When and how must I secure a well? Whenever you interrupt drilling operations, you must install a downhole safety device, such as a cement plug, bridge plug...

Distributed ignition method and apparatus for a combustion engine

DOEpatents

Willi, Martin L.; Bailey, Brett M.; Fiveland, Scott B.; Gong, Weidong

2006-03-07

A method and apparatus for operating an internal combustion engine is provided. The method comprises the steps of introducing a primary fuel into a main combustion chamber of the engine, introducing a pilot fuel into the main combustion chamber of the engine, determining an operating load of the engine, determining a desired spark plug ignition timing based on the engine operating load, and igniting the primary fuel and pilot fuel with a spark plug at the desired spark plug ignition timing. The method is characterized in that the octane number of the pilot fuel is lower than the octane number of the primary fuel.

Female professional divers. Similarities and differences between male and female professional divers.

PubMed

Irgens, Ågot; Troland, Kari; Grønning, Marit

2017-01-01

The aim of the present study was to explore the potential differences between female and male professional divers with regards to demographics, diving certificates, areas of diving, diving activity and health effects. The Norwegian Labour Inspection Authority's Diving certificate register contains data on all professional inshore divers who have held a certificate at any time since 1980. Forty nine per cent of these divers responded to the "Norwegian diver 2011" questionnaire. Of these divers 64 female and 1327 male divers completed the questionnaire about their professional diving career, certificate, year of onset and the year they stopped diving professionally if they were not still active in the diving industry. The level of general education was higher among female divers. More males than females were fully certified in diving. The mean age was lower among female than male fully certified divers. Fully certified female divers reported a lower total number of dives, shallower dives and diving for a shorter period of time than the male divers. They also had a lower percentage of work within the quay/construction sector and more often worked as teachers/instructors. A lower percentage of fully certified females than males had experienced decompression sickness (16.7% vs. 26.9%). Life-threatening events and psychologically challenging events were less common among females, as were adverse health effects. No such gender differences were seen for divers with a restricted certificate. The fully certified, female professional divers in our study had a very short diving career, reported fewer and shallower dives, and chose less physically demanding jobs than their male counterparts. They also had a higher level of education, reported less health problems and a better quality of life. The health effects seem to be related to the type of work rather than to gender.

Chronic daily headache with analgesics overuse in professional women breath-hold divers.

PubMed

Choi, Jay Chol; Lee, Jung Seok; Kang, Sa-Yoon; Kang, Ji-Hoon; Bae, Jong-Myon

2008-07-01

The object of this study is to investigate the prevalence and characteristics of headache in Korean professional women breath-hold divers, including their overuse of analgesics. Headache is a common problem encountered in clinical practice, and undersea divers exhibit unique causes of headache in addition to other common primary headaches. Many scuba divers are known to use various types of drugs to overcome dive-related symptoms or to enhance their underwater performance. The target population of this study was women divers in the northern district of Jeju Island who were registered in the divers' union. Data were collected using telephone interviews with a structured questionnaire. Headache was diagnosed and classified according to criteria of the International Headache Society. Nine hundred and eleven (80.3%) divers responded to the telephone interview. The prevalence rates of headache were 21.4% for tension-type headache and 9.1% for migraine. One hundred and four divers (11.4%) fulfilled the criteria for chronic daily headache (CDH). Overuse of combination analgesics was reported by 70.7% of divers. Women divers with CDH were significantly older and they complained more of tinnitus and dizziness, and had a greater history of hypertension than divers without headache. The prevalence of CDH is high in Korean professional women breath-hold divers, with many of them being combination-analgesics overusers.

78 FR 35976 - Petitions for Modification of Application of Existing Mandatory Safety Standards

Federal Register 2010, 2011, 2012, 2013, 2014

2013-06-14

.... (4) Training will be provided for operators to lower the grader blade to provide additional stopping... surface: (1) The operator will pump expanding cement slurry down the well to form a plug which runs from... operator will pump expanding cement slurry down the well to form a plug which runs from at least 200 feet...

Spark Plug Defects and Tests

NASA Technical Reports Server (NTRS)

Silsbee, F B; Loeb, L B; Sawyer, L G; Fonseca, E L; Dickinson, H C; Agnew, P G

1920-01-01

The successful operation of the spark plug depends to a large extent on the gas tightness of the plug. Part 1 of this report describes the method used for measuring the gas tightness of aviation spark plugs. Part 2 describes the methods used in testing the electrical conductivity of the insulation material when hot. Part 3 describes the testing of the cold dielectric strength of the insulation material, the resistance to mechanical shock, and the final engine test.

Peripheral cold acclimatization in Antarctic scuba divers.

PubMed

Bridgman, S A

1991-08-01

Peripheral acclimatization to cold in scuba divers stationed at the British Antarctic Survey's Signy Station was investigated during a year in Antarctica. Five divers and five non-diver controls underwent monthly laboratory tests of index finger immersion in cold water for 30 min. Index finger pulp temperature and time of onset of cold-induced vasodilatation (CIVD) were measured. Pain was recorded with verbal and numerical psychophysical subjective pain ratings. Average finger temperatures and median finger pain from 6-30 min of immersion, maximum finger temperatures during the first CIVD cycle, and finger temperatures at the onset of CIVD were calculated. Comparison of the variables recorded from divers and non-divers were performed with analysis of variance. No significant differences were found among the variables recorded from divers and non-divers. From a review of the literature, divers have responses typical of non-cold-adapted Caucasians. There is, therefore, no evidence that Signy divers peripherally acclimatized to cold. We suggest that these findings occur because either the whole body cooling which divers undergo inhibits peripheral acclimatization or because of insufficiently frequent or severe cold exposure while diving. Further basic studies on the duration, frequency and severity of cold exposure necessary to induce peripheral cold acclimatization are required before this question can be satisfactorily answered.

Divers Alert Network

MedlinePlus

... is Your Dive Safety Association Divers Alert Network DAN is Divers Alert Network, the diving industry’s largest ... Serving scuba divers for more than 30 years, DAN provides emergency assistance, medical information resources, educational opportunities ...

Oceanography for Divers: Waves, Tides, and Currents. Diver Education Series.

ERIC Educational Resources Information Center

Somers, Lee H.

To dive safely, it is suggested that the diver have a working knowledge of waves, tides, currents, and water quality. Lack of understanding and respect for ocean currents and surf can be of serious consequence to the diver. This paper on the diving environment is designed to provide the diver with a general understanding of the physical…

Knowing Your Partner: The Evolution of Brazilian Special Operations Forces

DTIC Science & Technology

2012-08-01

Government Palace in Port au Prince, Haiti. (Photo courtesy Brazilian Army Special Operations Brigade) Bottom left: Members from the Navy Combat Divers...States Government , Department of Defense, United States Special Operations Command, the Joint Special Operations University, or the Government of...its people, its economy, its government , and Brazilian policy toward the United States. General Pinheiro then presents a history and overview of

Reconnaissance of intertidal and subtidal zones of Back Island, Behm Canal, Southeast Alaska

DOE Office of Scientific and Technical Information (OSTI.GOV)

Strand, J.A.; Young, J.S.

1986-09-01

A diver reconnaissance of the intertidal and subtidal zones of Back Island, Southeast Alaska, was performed May 20-22, 1986. The specific objectives were to catalog potentially vulnerable shellfish, other invertebrates, and plant resources, and to identify potential herring spawning sites. This effort was designed to supplement the existing ecological data base for Back Island that would be used during the National Environmental Policy Act (NEPA) documentation process. A NEPA document will be prepared that describes the site environment and assesses impacts from the proposed construction and operation of the Southeast Alaska Acoustic Measurement Facility (SEAFAC). Nine diver transects were establishedmore » around Back Island. Particular attention was devoted to proposed locations for the pier and float facilities and range-operations and shore-power cable run-ups.« less

Joule-Thomson valves for long term service in space cryocoolers

NASA Technical Reports Server (NTRS)

Lester, J. M.; Benedict, B.

1985-01-01

Joule-Thomson valves for small cryocoolers have throttling passages on the order of 0.1 millimeter in diameter. Consequently, they can become plugged easily and stop the operation of the cooler. Plugging can be caused by solid particles, liquids or gases. Plugging is usually caused by the freezing of contaminant gases from the process stream. In small open loop coolers and in closed loop coolers where periodic maintenance is allowed, the problem is overcome by using careful assembly techniques, pure process gases, warm filters and cold adsorbers. A more thorough approach is required for closed loop cryocoolers which must operate unattended for long periods. This paper presents the results of an effort to solve this problem. The causes of plugging are examined, and various ways to eliminate plugging are discussed. Finally, the development of a J-T defroster is explained. It is concluded that a combination of preventive measures and a defroster will reduce the chance of cooler failure by plugging to such a degree that J-T coolers can be used for long term space missions.

Aeroacoustics of supersonic jet flows from contoured and solid/porous conical plug-nozzles

NASA Technical Reports Server (NTRS)

Dosanjh, Darshan S.; Das, Indu S.

1987-01-01

The results of an experimental study of the acoustic far-field, the shock associated noise, and the nature of the repetitive shock structure of supersonic jet flows issuing from plug-nozzles having externally-expanded plugs with pointed termination operated at a range of supercritical pressure ratios Xi approaching 2 to 4.5 are reported. The plug of one of these plug-nozzles was contoured. The other plug-nozzles had short conical plugs with either a solid surface or a combination of solid/porous surface of different porosities. The contoured and the uncontoured plug-nozzles had the same throat area and the same annulus-radius ratio K = R sub p/R sub N = 0.43. As the result of modifications of the shock structure, the acoustic performance of improperly expanded jet flows of an externally-expanded short uncontoured plug of an appropriate geometry with suitably perforated plug and a pointed termination, is shown to approach the acoustic performance of a shock-free supersonic jet issuing from an equivalent externally-expanded contoured plug-nozzle.

Plug-in nanoliter pneumatic liquid dispenser with nozzle design flexibility

PubMed Central

Choi, In Ho; Kim, Hojin; Lee, Sanghyun; Baek, Seungbum; Kim, Joonwon

2015-01-01

This paper presents a novel plug-in nanoliter liquid dispensing system with a plug-and-play interface for simple and reversible, yet robust integration of the dispenser. A plug-in type dispenser was developed to facilitate assembly and disassembly with an actuating part through efficient modularization. The entire process for assembly and operation of the plug-in dispenser is performed via the plug-and-play interface in less than a minute without loss of dispensing quality. The minimum volume of droplets pneumatically dispensed using the plug-in dispenser was 124 nl with a coefficient of variation of 1.6%. The dispensed volume increased linearly with the nozzle size. Utilizing this linear relationship, two types of multinozzle dispensers consisting of six parallel channels (emerging from an inlet) and six nozzles were developed to demonstrate a novel strategy for volume gradient dispensing at a single operating condition. The droplet volume dispensed from each nozzle also increased linearly with nozzle size, demonstrating that nozzle size is a dominant factor on dispensed volume, even for multinozzle dispensing. Therefore, the proposed plug-in dispenser enables flexible design of nozzles and reversible integration to dispense droplets with different volumes, depending on the application. Furthermore, to demonstrate the practicality of the proposed dispensing system, we developed a pencil-type dispensing system as an alternative to a conventional pipette for rapid and reliable dispensing of minute volume droplets. PMID:26594263

Plug-in nanoliter pneumatic liquid dispenser with nozzle design flexibility.

PubMed

Choi, In Ho; Kim, Hojin; Lee, Sanghyun; Baek, Seungbum; Kim, Joonwon

2015-11-01

This paper presents a novel plug-in nanoliter liquid dispensing system with a plug-and-play interface for simple and reversible, yet robust integration of the dispenser. A plug-in type dispenser was developed to facilitate assembly and disassembly with an actuating part through efficient modularization. The entire process for assembly and operation of the plug-in dispenser is performed via the plug-and-play interface in less than a minute without loss of dispensing quality. The minimum volume of droplets pneumatically dispensed using the plug-in dispenser was 124 nl with a coefficient of variation of 1.6%. The dispensed volume increased linearly with the nozzle size. Utilizing this linear relationship, two types of multinozzle dispensers consisting of six parallel channels (emerging from an inlet) and six nozzles were developed to demonstrate a novel strategy for volume gradient dispensing at a single operating condition. The droplet volume dispensed from each nozzle also increased linearly with nozzle size, demonstrating that nozzle size is a dominant factor on dispensed volume, even for multinozzle dispensing. Therefore, the proposed plug-in dispenser enables flexible design of nozzles and reversible integration to dispense droplets with different volumes, depending on the application. Furthermore, to demonstrate the practicality of the proposed dispensing system, we developed a pencil-type dispensing system as an alternative to a conventional pipette for rapid and reliable dispensing of minute volume droplets.

Isolation, Enumeration, and Characterization of Aeromonas from Polluted Waters Encountered in Diving Operations

PubMed Central

Seidler, Ramon J.; Allen, D. A.; Lockman, H.; Colwell, R. R.; Joseph, S. W.; Daily, O. P.

1980-01-01

Counts of total viable, aerobic, heterotrophic bacteria, indicator organisms, and Aeromonas spp. were made at a diver training site on the Anacostia River in Washington, D.C. The numbers of Aeromonas cells in Anacostia River sediment and water increased during periods of elevated water temperature, to maxima of 4 × 105 cells per g of sediment and 300 cells per ml of water. Correspondingly, Aeromonas counts dropped 2 to 4 logs as the water temperature decreased to 0 to 0.5°C. Cultures taken by sterile swabs from the ears and face masks of divers after a 30-min swim in the Anacostia River yielded bacterial types and numbers similar to those found in the river. The nasal passages of the divers apparently did not become contaminated by swimming, possibly because of the protective effect of the face masks used by the divers. Properties associated with virulence in Aeromonas hydrophila and Aeromonas sobria strains isolated from the river, sediment, and divers were investigated. Nearly 40% of the strains of both species collected during the study produced cytotoxic activity for mouse Y-1 adrenal cells, as well as elastase. Enterotoxin activity, as detected by the Y-1 assay, was observed in 3% (1 of 35) of the strains of A. sobria and in 6% (19 of 330) of the A. hydrophila strains. Fluid accumulation in rabbit ileal loops induced by both species of Aeromonas varied greatly among the 17 strains examined. Fluid accumulation of at least 0.4 ml/cm was correlated with positive cytotoxin- or enterotoxin-like response in the Y-1 tissue culture assay. PMID:7396482

Procedures manual for compressed air diving (scuba mode).

DOT National Transportation Integrated Search

1980-01-01

The Virginia Department of Highways and Transportation conducts underwater inspection, maintenance, and salvage activities as part of its routine operations. These activities are carried out by divers from the private sector working on a contract bas...

Macromolecular crystal growing system

NASA Technical Reports Server (NTRS)

Snyder, Robert S. (Inventor); Herren, Blair J. (Inventor); Carter, Daniel C. (Inventor); Yost, Vaughn H. (Inventor); Bugg, Charles E. (Inventor); Delucas, Lawrence J. (Inventor); Suddath, Fred L. (Inventor)

1991-01-01

A macromolecular crystal growing system especially designed for growing crystals in the low gravity of space as well as the gravity of earth includes at least one tray assembly, a carrier assembly which receives the tray, and a refrigeration-incubation module in which the carrier assembly is received. The tray assembly includes a plurality of sealed chambers with a plastic syringe and a plug means for the double tip of the syringe provided therein. Ganging mechanisms operate the syringes and plugs simultaneously in a precise and smooth operation. Preferably, the tray assemblies are mounted on ball bearing slides for smooth operation in inserting and removing the tray assemblies into the carrier assembly. The plugging mechanism also includes a loading control mechanism. A mechanism for leaving a syringe unplugged is also provided.

Correlation between 99Tcm-HMPAO-SPECT brain image and a history of decompression illness or extent of diving experience in commercial divers.

PubMed Central

Shields, T G; Duff, P M; Evans, S A; Gemmell, H G; Sharp, P F; Smith, F W; Staff, R T; Wilcock, S E

1997-01-01

OBJECTIVES: To explore the use of 99technetiumm-hexamethyl propylene amine oxime single photon computed tomography (HMPAO-SPECT) of the brain as a means of detecting nervous tissue damage in divers and to determine if there is any correlation between brain image and a diver's history of diving or decompression illness (DCI). METHODS: 28 commercial divers with a history of DCI, 26 divers with no history of DCI, and 19 non-diving controls were examined with brain HMPAO-SPECT. Results were classified by observer assessment as normal (I) or as a pattern variants (II-V). The brain images of a subgroup of these divers (n = 44) and the controls (n = 17) were further analysed with a first order texture analysis technique based on a grey level histogram. RESULTS: 15 of 54 commercial divers (28%) were visually assessed as having HMPAO-SPECT images outside normal limits compared with 15.8% in appropriately identified non-diver control subjects. 18% of divers with a history of DCI were classified as having a pattern different from the normal image compared with 38% with no history of DCI. No association was established between the presence of a pattern variant from the normal image and history of DCI, diving, or other previous possible neurological insult. On texture analysis of the brain images, divers had a significantly lower mean grey level (MGL) than non-divers. Divers with a history of DCI (n = 22) had a significantly lower MGL when compared with divers with no history of DCI (n = 22). Divers with > 14 years professional diving or > 100 decompression days a year had a significantly lower MGL value. CONCLUSIONS: Observer assessment of HMPAO-SPECT brain images can lead to disparity in results. Texture analysis of the brain images supplies both an objective and consistent method of measurement. A significant correlation was found between a low measure of MGL and a history of DCI. There was also an indication that diving itself had an effect on texture measurement, implying that it had caused subclinical nervous tissue damage. PMID:9166130

LOX/Methane Main Engine Glow Plug Igniter Tests and Modeling

NASA Technical Reports Server (NTRS)

Breisacher, Kevin; Ajmani, Kumud

2009-01-01

Ignition data for tests with a LOX/methane igniter that utilized a glow plug as the ignition source are presented. The tests were conducted in a vacuum can with thermally conditioned (cold) hardware. Data showing the effects of glow plug geometry, type, and igniter operating conditions are discussed. Comparisons between experimental results and multidimensional, transient computer models are also made.

Shock-operated valve would automatically protect fluid systems

NASA Technical Reports Server (NTRS)

Branum, L. W.; Wells, G. H.

1966-01-01

Glandless valve shuts down high-pressure fluid systems when severe shock from an explosion or earthquake occurs. The valve uses a pendulum to support the valve closure plug in the open position. When jarred, the valve body is moved relative to the pendulum and the plug support is displaced, allowing the plug to seat and be held by spring pressure.

Diver-based integrated navigation/sonar sensor

NASA Astrophysics Data System (ADS)

Lent, Keith H.

1999-07-01

Two diver based systems, the Small Object Locating Sonar (SOLS) and the Integrated Navigation and Sonar Sensor (INSS) have been developed at Applied Research Laboratories, the University of Texas at Austin (ARL:UT). They are small and easy to use systems that allow a diver to: detect, classify, and identify underwater objects; render large sector visual images; and track, map and reacquire diver location, diver path, and target locations. The INSS hardware consists of a unique, simple, single beam high resolution sonar, an acoustic navigation systems, an electronic depth gauge, compass, and GPS and RF interfaces, all integrated with a standard 486 based PC. These diver sonars have been evaluated by the very shallow water mine countermeasure detachment since spring 1997. Results are very positive, showing significantly greater capabilities than current diver held systems. For example, the detection ranges are increased over existing systems, and the system allows the divers to classify mines at a significant stand off range. As a result, the INSS design has been chosen for acquisition as the next generation diver navigation and sonar system. The EDMs for this system will be designed and built by ARL:UT during 1998 and 1999 with production planned in 2000.

[Patent foramen ovale and decompression illness in divers].

PubMed

Sivertsen, Wiebke; Risberg, Jan; Norgård, Gunnar

2010-04-22

About 25 % of the population has patent foramen ovale, and the condition has been assumed to be a causal factor in decompressive illness. Transcatheter closure is possible and is associated with a relatively low risk, but it has not been clarified whether there is an indication for assessment and treatment of the condition in divers. The present study explored a possible relationship between a patent foramen ovale and the risk for decompression illness in divers, if there are categories of divers that should be screened for the condition and what advice should be given to divers with this condition. The review is based on literature identified through a search in Pubmed and the authors' long clinical experience in the field. The risk of decompression illness for divers with a persistent foramen ovale is about five times higher than that in divers without this condition, but the absolute risk for decompression illness is only 2.5 after 10,000 dives. A causal association has not been shown between patent foramen ovale and decompression illness. Even if closure of patent foramen ovale may be done with relatively small risk, the usefulness of the procedure has not been documented in divers. We do not recommend screening for patent foramen ovale in divers because the absolute risk of decompression illness is small and transcatheter closure is only indicated after decompression illness in some occupational divers.

KSC-02pd1298

NASA Image and Video Library

2002-09-12

KENNEDY SPACE CENTER, FLA. -- Andy Fish, an SRB retrieval diver and diver medical technician with United Space Alliance, is in the spotlight for helping rescue a diver in distress off Cape Canaveral Sept. 11. Fish and others were on a certification exercise on board Freedom Star, one of the Shuttle Rocket Booster retrieval ships, manned by USA workers. The ship was near the location of a lobster diving boat that radioed the U.S. Coast Guard for help when one of the divers experienced difficulty breathing on his return to the surface. Hearing the call for help, the captain of the Freedom Star offered to help. Fish had experience with distressed divers. He stayed with the diver in the recompression chamber aboard the Freedom Star until the ship reached Port Canaveral where a KSC Occupational Health doctor waited. The diver was stabilized and taken to Florida Hospital. .

Use of handheld sonar to locate a missing diver.

PubMed

McGrane, Owen; Cronin, Aaron; Hile, David

2013-03-01

The purpose of this study was to investigate whether a handheld sonar device significantly reduces the mean time needed to locate a missing diver. This institutional review board approved, prospective, crossover study used a voluntary convenience sample of 10 scuba divers. Participants conducted both a standard and modified search to locate a simulated missing diver. The standard search utilized a conventional search pattern starting at the point where the missing diver (simulated) was last seen. The modified search used a sonar beacon to augment the search. For each search method, successful completion of the search was defined as locating the missing diver within 40 minutes. Twenty total dives were completed. Using a standard search pattern, the missing diver was found by only 1 diver (10%), taking 18 minutes and 45 seconds. In the sonar-assisted search group, the missing diver was found by all 10 participants (100%), taking an average of 2 minutes and 47 seconds (SD 1 minute, 20 seconds). Using the nonparametric related samples Wilcoxon signed rank test, actual times between the sonar group and the standard group were significant (P < .01). Using paired samples t tests, the sonar group's self-assessed confidence increased significantly after using the sonar (P < .001), whereas the standard group decreased in confidence (not statistically significant, P = .111). Handheld sonar significantly reduces the mean duration to locate a missing diver as well as increasing users' confidence in their ability to find a missing diver when compared with standard search techniques. Copyright © 2013 Wilderness Medical Society. Published by Elsevier Inc. All rights reserved.

A Lot of Good Physics in the Cartesian Diver

ERIC Educational Resources Information Center

De Luca, Roberto; Ganci, Salvatore

2011-01-01

The Cartesian diver experiment certainly occupies a place of honour in old physics textbooks as a vivid demonstration of Archimedes' buoyancy. The original experiment, as described in old textbooks, shows Archimedes buoyancy qualitatively: when the increased weight of the diver is not counterbalanced by Archimedes' buoyancy, the diver sinks. When…

46 CFR 197.346 - Diver's equipment.

Code of Federal Regulations, 2012 CFR

2012-10-01

... breathing gas supply with a cylinder pressure gage readable by the diver during the dive; and (ii) A diver... (8) A depth gage. (b) Each diver using a heavyweight diving outfit must— (1) Have a helmet group consisting of helmet, breastplate, and associated valves and connections; (2) Have a diving dress group...

46 CFR 197.346 - Diver's equipment.

Code of Federal Regulations, 2013 CFR

2013-10-01

... breathing gas supply with a cylinder pressure gage readable by the diver during the dive; and (ii) A diver... (8) A depth gage. (b) Each diver using a heavyweight diving outfit must— (1) Have a helmet group consisting of helmet, breastplate, and associated valves and connections; (2) Have a diving dress group...

Quantum well infrared photodetectors (QWIP) with selectively regrown N-GaAs plugs

NASA Astrophysics Data System (ADS)

Matsukura, Yusuke; Nishino, Hironori; Tanaka, Hitoshi; Fujii, Toshio

2001-10-01

We fabricated the GaAs/AlGaAs Quantum Well Infrared Photo detector (QWIP) focal plane array with selectively re-grown N- GaAs interconnection plugs and demonstrated its device operation, in order to establish the technology to obtain both complex device functions and device manufacturability. MBE (Molecular Beam Epitaxy) grown QWIP MQW wafers were covered with SiON and SiNx mask films to obtain selectivity of the re-growth process. N-GaAs plugs were re-grown selectively with low-pressure MOCVD (Metal-Organic Chemical Vapor Deposition) with AsH3 and Dimethylgalliumchloride as precursors, only on the bottom surfaces of the holes for the interconnection to extract the electrodes from the underlying epilayer. Cross- sectional SEM observation revealed that the feature of the re- grown N-GaAs plugs was triangular, rather than rectangular as expected. The reason for this discrepancy is not yet clear. The electrical contact between the epilayer and re-grown N- GaAs plug was 'ohmic-like,' without any trace of interfacial barrier. The Current-Voltage characteristics of the fabricated QWIP device showed no tangible leakage current between the N- GaAs plug and device structure, indicating that electrical insulation between the N-GaAs plugs and device structure was sufficient. Fabricated devices were successfully operated as a hybrid focal plane array, indicating the selective re-growth was a promising technique to realize complex QWIP based devices.

Liquid microjunction surface sampling probe fluid dynamics: Characterization and application of an analyte plug formation operational mode

DOE Office of Scientific and Technical Information (OSTI.GOV)

ElNaggar, Mariam S.; Van Berkel, Gary J.

2011-08-10

The recently discovered sample plug formation and injection operational mode of a continuous flow, coaxial tube geometry, liquid microjunction surface sampling probe (LMJ-SSP) (J. Am. Soc. Mass Spectrom, 2011) was further characterized and applied for concentration and mixing of analyte extracted from multiple areas on a surface and for nanoliter-scale chemical reactions of sampled material. A transparent LMJ-SSP was constructed and colored analytes were used so that the surface sampling process, plug formation, and the chemical reactions could be visually monitored at the sampling end of the probe before being analyzed by mass spectrometry of the injected sample plug. Injectionmore » plug peak widths were consistent for plug hold times as long as the 8 minute maximum attempted (RSD below 1.5%). Furthermore, integrated injection peak signals were not significantly different for the range of hold times investigated. The ability to extract and completely mix individual samples within a fixed volume at the sampling end of the probe was demonstrated and a linear mass spectral response to the number of equivalent analyte spots sampled was observed. Lastly, using the color and mass changing chemical reduction of the redox dye 2,6-dichlorophenol-indophenol with ascorbic acid, the ability to sample, concentrate, and efficiently run reactions within the same plug volume within the probe was demonstrated.« less

Extending lean operating limit and reducing emissions of methane spark-ignited engines using a microwave-assisted spark plug

DOE PAGES

Rapp, Vi H.; DeFilippo, Anthony; Saxena, Samveg; ...

2012-01-01

Amore » microwave-assisted spark plug was used to extend the lean operating limit (lean limit) and reduce emissions of an engine burning methane-air. In-cylinder pressure data were collected at normalized air-fuel ratios of λ = 1.46, λ = 1.51, λ = 1.57, λ = 1.68, and λ = 1.75. For each λ , microwave energy (power supplied to the magnetron per engine cycle) was varied from 0 mJ (spark discharge alone) to 1600 mJ. At lean conditions, the results showed adding microwave energy to a standard spark plug discharge increased the number of complete combustion cycles, improving engine stability as compared to spark-only operation. Addition of microwave energy also increased the indicated thermal efficiency by 4% at λ = 1.68. At λ = 1.75, the spark discharge alone was unable to consistently ignite the air-fuel mixture, resulting in frequent misfires. Although microwave energy produced more consistent ignition than spark discharge alone at λ = 1.75, 59% of the cycles only partially burned. Overall, the microwave-assisted spark plug increased engine performance under lean operating conditions (λ = 1.68) but did not affect operation at conditions closer to stoichiometric.« less

Managing scuba divers to meet ecological goals for coral reef conservation.

PubMed

Sorice, Michael G; Oh, Chi-Ok; Ditton, Robert B

2007-06-01

Marine protected areas increasingly are challenged to maintain or increase tourism benefits while adequately protecting resources. Although carrying capacity strategies can be used to cope with use-related impacts, there is little understanding of divers themselves, their management preferences, and how preferences relate to conservation goals. By using a stated preference choice modeling approach, we investigated the choices divers make in selecting diving trips to marine protected areas as defined by use level, access, level of supervision, fees, conservation education, and diving expectations. Logit models showed that divers preferred a more restrictive management scenario over the status quo. Divers favored reductions in the level of site use and increased levels of conservation education. Divers did not favor fees to access protected areas, having less access to the resource, or extensive supervision. Finally, divers were much more willing to accept increasingly restrictive management scenarios when they could expect to see increased marine life.

Understanding the underwater behaviour of scuba divers in Hong Kong.

PubMed

Chung, Shan-Shan; Au, Alfred; Qiu, Jian-Wen

2013-04-01

Diving-related activities may constitute a major threat to coral reefs. This study aimed to quantify the impact of diving in Hong Kong on hard corals and understand how socio-economic characteristics and experience level of divers influence diver-inflicted damage. We recorded and analysed the underwater behaviour of 81 recreational divers. On average, a diver was in contact with marine biota 14.7 times with about 40% of contacts involved corals and 38% were damaging contacts with corals or other biota in a single dive. The most harm-inflicting groups included inexperienced and camera-carrying divers. Although Hong Kong divers did not make many damaging contacts with corals, there is still an imminent need to determine the scale of damage from diving activities on the marine ecosystem given the rapid development of marine-based tourism and the limited coral-inhabited areas in Hong Kong where the marine environment is already under stress from anthropogenic activities.

Understanding the Underwater Behaviour of Scuba Divers in Hong Kong

NASA Astrophysics Data System (ADS)

Chung, Shan-shan; Au, Alfred; Qiu, Jian-Wen

2013-04-01

Diving-related activities may constitute a major threat to coral reefs. This study aimed to quantify the impact of diving in Hong Kong on hard corals and understand how socio-economic characteristics and experience level of divers influence diver-inflicted damage. We recorded and analysed the underwater behaviour of 81 recreational divers. On average, a diver was in contact with marine biota 14.7 times with about 40 % of contacts involved corals and 38 % were damaging contacts with corals or other biota in a single dive. The most harm-inflicting groups included inexperienced and camera-carrying divers. Although Hong Kong divers did not make many damaging contacts with corals, there is still an imminent need to determine the scale of damage from diving activities on the marine ecosystem given the rapid development of marine-based tourism and the limited coral-inhabited areas in Hong Kong where the marine environment is already under stress from anthropogenic activities.

Friction plug welding

NASA Technical Reports Server (NTRS)

Takeshita, Riki (Inventor); Hibbard, Terry L. (Inventor)

2001-01-01

Friction plug welding (FPW) usage is advantageous for friction stir welding (FSW) hole close-outs and weld repairs in 2195 Al--Cu--Li fusion or friction stir welds. Current fusion welding methods of Al--Cu--Li have produced welds containing varied defects. These areas are found by non-destructive examination both after welding and after proof testing. Current techniques for repairing typically small (<0.25) defects weaken the weldment, rely heavily on welders' skill, and are costly. Friction plug welding repairs increase strength, ductility and resistance to cracking over initial weld quality, without requiring much time or operator skill. Friction plug welding while pulling the plug is advantageous because all hardware for performing the weld can be placed on one side of the workpiece.

Prolonged dry apnoea: effects on brain activity and physiological functions in breath-hold divers and non-divers.

PubMed

Ratmanova, Patricia; Semenyuk, Roxana; Popov, Daniil; Kuznetsov, Sergey; Zelenkova, Irina; Napalkov, Dmitry; Vinogradova, Olga

2016-07-01

The aim of the study was to investigate the effects of voluntary breath-holding on brain activity and physiological functions. We hypothesised that prolonged apnoea would trigger cerebral hypoxia, resulting in a decrease of brain performance; and the apnoea's effects would be more pronounced in breath-hold divers. Trained breath-hold divers and non-divers performed maximal dry breath-holdings. Lung volume, alveolar partial pressures of O2 and CO2, attention and anxiety levels were estimated. Heart rate, blood pressure, arterial blood oxygenation, brain tissue oxygenation, EEG, and DC potential were monitored continuously during breath-holding. There were a few significant changes in electrical brain activity caused by prolonged apnoea. Brain tissue oxygenation index and DC potential were relatively stable up to the end of the apnoea in breath-hold divers and non-divers. We also did not observe any decrease of attention level or speed of processing immediately after breath-holding. Interestingly, trained breath-hold divers had some peculiarities in EEG activity at resting state (before any breath-holding): non-spindled, sharpened alpha rhythm; slowed-down alpha with the frequency nearer to the theta band; and untypical spatial pattern of alpha activity. Our findings contradicted the primary hypothesis. Apnoea up to 5 min does not lead to notable cerebral hypoxia or a decrease of brain performance in either breath-hold divers or non-divers. It seems to be the result of the compensatory mechanisms similar to the diving response aimed at centralising blood circulation and reducing peripheral O2 uptake. Adaptive changes during apnoea are much more prominent in trained breath-hold divers.

Injury survey in scuba divers of British Sub-Aqua Club: A retrospective study

PubMed Central

Hyun, Gwang-Suk; Jee, Yong-Seok; Park, Jung-Min; Cho, Nam-Heung; Cha, Jun-Youl

2015-01-01

Scuba diving itself is generally known as a safe sports. However, various injury accidents can happen, and the incidences vary depending on divers’ education grade levels about the risks. Therefore, the study set out to identify and analyze the causes and patterns of injuries depending on the divers’ safety education grade levels through a questionnaire survey targeting ocean divers (n=12), sports divers (n=16), and dive leaders (n=15), all of whom belong to the British Sub-Aqua Club. After conducting a frequency analysis on the collected questionnaires, the conclusions are made as follows. First, in terms of diving depth, the most frequent diving depth was 15–20 m among ocean divers, 20–25 m among sports divers, and 15–20 m in case of dive leaders. Second, with regard to the causes of injuries, the most frequently answered causes are ‘overtension’ and ‘low skill’ among ocean divers; ‘low skill’ among sports divers; ‘overaction’ among dive leaders. Third, in terms of injury patterns, the most frequently answered injury patterns are ‘ear’ injuries among ocean divers; ‘ankle’ injuries among sports divers; ‘ankle’ and ‘calf’ injuries among dive leaders. Fourth, with regard to who performed first-aid when an injury accident happened, the most frequent answers are ‘instructor’ among ocean divers; ‘instructor’ and ‘self’ among sports divers; ‘self’ among dive leaders. We might suggest that more efforts need to be made to improve divers’ low dependence on specialists for treatment and consultation so that we can prevent an injury from leading to the second injury accident. PMID:26730384

Normative tolerances for scuba divers and snorkelers: An application of the Potential for Conflict index2

Treesearch

Lauren M. Heesemann; Jerry J. Vaske; David K. Loomis

2010-01-01

This study examines Florida Keys snorkeler and SCUBA diver encounter norms using the Potential for Conflict Index2 (PCI2). Snorkelers and SCUBA divers evaluated the acceptability of encountering a specific number of other snorkelers and SCUBA divers on a 7-point scale ranging from extremely acceptable (3) to extremely...

A suspended dive-net technique for catching territorial divers

USGS Publications Warehouse

Uher-Koch, Brian D.; Rizzolo, Daniel; Wright, Kenneth G.; Schmutz, Joel A.

2016-01-01

A variety of methods such as night-lighting and lift nets have been used to catch divers (Gavidae), although 24-hour daylight in the Arctic summer and the remote nature of field sites can make the use of these traditional methods impossible. Our research required capture of adult divers at remote locations in northern Alaska. Here we describe a suspended dive-net technique that we used to safely capture territorial White-billed Gavia adamsii and Pacific Divers G. pacifica and that is lightweight and easy to set up. We also were able to capture divers with chicks, and failed breeders, and suggest that this method could be used to catch other territorial aquatic diving birds, especially other diver species.

Analytical and experimental study of axisymmetric truncated plug nozzle flow fields

NASA Technical Reports Server (NTRS)

Muller, T. J.; Sule, W. P.; Fanning, A. E.; Giel, T. V.; Galanga, F. L.

1972-01-01

Experimental and analytical investigation of the flow field and base pressure of internal-external-expansion truncated plug nozzles are discussed. Experimental results for two axisymmetric, conical plug-cylindrical shroud, truncated plug nozzles are presented for both open and closed wake operations. These results include extensive optical and pressure data covering nozzle flow field and base pressure characteristics, diffuser effects, lip shock strength, Mach disc behaviour, and the recompression and reverse flow regions. Transonic experiments for a special planar transonic section are presented. An extension of the analytical method of Hall and Mueller to include the internal shock wave from the shroud exit is presented for closed wake operation. Results of this analysis include effects on the flow field and base pressure of ambient pressure ratio, nozzle geometry, and the ratio of specific heats. Static thrust is presented as a function of ambient pressure ratio and nozzle geometry. A new transonic solution method is also presented.

Multi-Scale Measures of Rugosity, Slope and Aspect from Benthic Stereo Image Reconstructions

PubMed Central

Friedman, Ariell; Pizarro, Oscar; Williams, Stefan B.; Johnson-Roberson, Matthew

2012-01-01

This paper demonstrates how multi-scale measures of rugosity, slope and aspect can be derived from fine-scale bathymetric reconstructions created from geo-referenced stereo imagery. We generate three-dimensional reconstructions over large spatial scales using data collected by Autonomous Underwater Vehicles (AUVs), Remotely Operated Vehicles (ROVs), manned submersibles and diver-held imaging systems. We propose a new method for calculating rugosity in a Delaunay triangulated surface mesh by projecting areas onto the plane of best fit using Principal Component Analysis (PCA). Slope and aspect can be calculated with very little extra effort, and fitting a plane serves to decouple rugosity from slope. We compare the results of the virtual terrain complexity calculations with experimental results using conventional in-situ measurement methods. We show that performing calculations over a digital terrain reconstruction is more flexible, robust and easily repeatable. In addition, the method is non-contact and provides much less environmental impact compared to traditional survey techniques. For diver-based surveys, the time underwater needed to collect rugosity data is significantly reduced and, being a technique based on images, it is possible to use robotic platforms that can operate beyond diver depths. Measurements can be calculated exhaustively at multiple scales for surveys with tens of thousands of images covering thousands of square metres. The technique is demonstrated on data gathered by a diver-rig and an AUV, on small single-transect surveys and on a larger, dense survey that covers over . Stereo images provide 3D structure as well as visual appearance, which could potentially feed into automated classification techniques. Our multi-scale rugosity, slope and aspect measures have already been adopted in a number of marine science studies. This paper presents a detailed description of the method and thoroughly validates it against traditional in-situ measurements. PMID:23251370

Cohort Study of Multiple Brain Lesions in Sport Divers: Role of a Patent Foramen Ovale

NASA Technical Reports Server (NTRS)

Knauth, Michael; Ries, Stefan; Pohimann, Stefan; Kerby, Tina; Forstring, Michael; Daffertshofer, Michael; Hennerici,Michael; Sartor, Klaus

1997-01-01

To investigate the role of a patent foramen ovale in the pathogenesis of multiple brain lesions acquired by sport divers in the absence of reported decompression symptoms. Design: Prospective double blind cohort study. . Setting Diving clubs around Heidelberg and departments of neuroradiology and neurology. Subjects: 87 sport divers with a minimum of 160 scuba dives (dives with self contained underwater breathing apparatus). Main outcome measures: Presence of multiple brain lesions visualised by cranial magnetic resonance imaging and presence and size of patent foramen ovale as documented by echocontrast transcranial Doppler ultrasonograhy. Results: 25 subjects were found to have a right-to-left shunt, 13 with a patent foramen ovale of high haemodynamic relevance. A total of 41 brain lesions were detected in 11 divers. There were seven brain lesions in seven divers without a right-to-left shunt and 34 lesions in four divers with a right-to-left shunt Multiple brain lesions occurred exclusively in three divers with a large patent foramen ovale (P=0.004). Conclusions: Multiple brain lesions in sport divers were associated with presence of a large patent foramen ovale. This association suggests paradoxical gas embolism as the pathological mechanism. A patent foramen ovale of high haemodynamic relevance seems to be an important risk factor for developing multiple brain lesions in sport divers.

The Cartesian Diver, Surface Tension and the Cheerios Effect

ERIC Educational Resources Information Center

Chen, Chi-Tung; Lee, Wen-Tang; Kao, Sung-Kai

2014-01-01

A Cartesian diver can be used to measure the surface tension of a liquid to a certain extent. The surface tension measurement is related to the two critical pressures at which the diver is about to sink and about to emerge. After sinking because of increasing pressure, the diver is repulsed to the centre of the vessel. After the pressure is…

Are the Keys loved to death? A study of diver specialization levels and preferences in the Florida Keys

Treesearch

Shona Paterson; David K. Loomis

2010-01-01

This paper presents research conducted for the Florida Reef Resilience Program on nonresident recreational SCUBA divers in three zones of the Florida Keys. When divers were segmented into specialization subgroups for analysis, divers in different subgroups tended to use different geographic locations. These results suggest differences in user preferences; yet when...

U.S., Pennsylvania Collaborate on Well-Plugging Case to Protect Drinking Water

EPA Pesticide Factsheets

A case that led to prison and fines for an operator who improperly plugged old oil wells in the Allegheny Forest in Elk County, Pennsylvania, began when EPA’s Dave Rectenwald noticed something amiss.

Comparative incidences of decompression illness in repetitive, staged, mixed-gas decompression diving: is 'dive fitness' an influencing factor?

PubMed

Sayer, Martin Dj; Akroyd, Jim; Williams, Guy D

2008-06-01

Wreck diving at Bikini Atoll consists of a relatively standard series of decompression dives with maximum depths in the region of 45-55 metres' sea water (msw). In a typical week of diving at Bikini, divers can perform up to 12 decompression dives to these depths over seven days; on five of those days, divers can perform two decompression dives per day. All the dives employ multi-level, staged decompression schedules using air and surface-supplied nitrox containing 80% oxygen. Bikini is serviced by a single diving operator and so a relatively precise record exists both of the actual number of dives undertaken and of the decompression illness incidents both for customer divers and the dive guides. The dive guides follow exactly the dive profiles and decompression schedules of the customers. Each dive guide will perform nearly 400 decompression dives a year, with maximum depths mostly around 50 msw, compared with an average of 10 (maximum of 12) undertaken typically by each customer diver in a week. The incidence of decompression illness for the customer population (presumed in the absence of medical records) is over ten times higher than that for the dive guides. The physiological reasons for such a marked difference are discussed in terms of customer demographics and dive-guide acclimatization to repetitive decompression stress. The rates of decompression illness for a range of diving populations are reviewed.

Benefits of Using Remotely Operated Vehicles to Inspect USACE Navigation Structures

DTIC Science & Technology

2007-03-01

ER D C/ CR R EL T R -0 7 -4 Benefits of Using Remotely Operated Vehicles to Inspect USACE Navigation Structures James H. Lever, Gary E...release; distribution is unlimited. ERDC/CRREL TR-07-4 March 2007 Benefits of Using Remotely Operated Vehicles to Inspect USACE Navigation...with inspections using divers or dewatering. In each case, benefits from reduced labor costs, shipping delays, and lost power production far exceed

Otorhinolaryngologic disorders and diving accidents: an analysis of 306 divers.

PubMed

Klingmann, Christoph; Praetorius, Mark; Baumann, Ingo; Plinkert, Peter K

2007-10-01

Diving is a very popular leisure activity with an increasing number of participants. As more than 80% of the diving related problems involve the head and neck region, every otorhinolaryngologist should be familiar with diving medical standards. We here present an analysis of more than 300 patients we have treated in the past four years. Between January 2002 and October 2005, 306 patients presented in our department with otorhinological disorders after diving, or after diving accidents. We collected the following data: name, sex, age, date of treatment, date of accident, diagnosis, special aspects of the diagnosis, number of dives, diving certification, whether and which surgery had been performed, history of acute diving accidents or follow up treatment, assessment of fitness to dive and special remarks. The study setting was a retrospective cohort study. The distribution of the disorders was as follows: 24 divers (8%) with external ear disorders, 140 divers (46%) with middle ear disorders, 56 divers (18%) with inner ear disorders, 53 divers (17%) with disorders of the nose and sinuses, 24 divers (8%) with decompression illness (DCI) and 9 divers (3%) who complained of various symptoms. Only 18% of the divers presented with acute disorders. The most common disorder (24%) was Eustachian tube dysfunction. Female divers were significantly more often affected. Chronic sinusitis was found to be associated with a significantly higher number of performed dives. Conservative treatment failed in 30% of the patients but sinus surgery relieved symptoms in all patients of this group. The middle ear is the main problem area for divers. Middle ear ventilation problems due to Eustachian tube dysfunction can be treated conservatively with excellent results whereas pathology of the tympanic membrane and ossicular chain often require surgery. More than four out of five patients visited our department to re-establish their fitness to dive. Although the treatment of acute diving-related disorders is an important field for the treatment of divers, the main need of divers seems to be assessment and recovery of their fitness to dive.

City of Las Vegas Plug-in Hybrid Electric Vehicle Demonstration Program

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2013-12-31

The City of Las Vegas was awarded Department of Energy (DOE) project funding in 2009, for the City of Las Vegas Plug-in Hybrid Electric Vehicle Demonstration Program. This project allowed the City of Las Vegas to purchase electric and plug-in hybrid electric vehicles and associated electric vehicle charging infrastructure. The City anticipated the electric vehicles having lower overall operating costs and emissions similar to traditional and hybrid vehicles.

Incidence and Features of Barodontalgia Among Military Divers.

PubMed

Gunepin, Mathieu; Derache, Florence; Blatteau, Jean-Eric; Nakdimon, Idan; Zadik, Yehuda

2016-02-01

Divers are vulnerable to barodontalgia (atmospheric pressure change related dental pain), which may jeopardize diving safety and mission completion. Our aim was to investigate the experience of barodontalgia among western military divers. French Armed Forces diving personnel were asked to answer a structured questionnaire including questions regarding their oral health, diving and career features, and barodontalgia while diving. For analysis, the participants were divided into commando/clearance divers (Group A) and ship divers (Group B). All the requested 1389 divers agreed to participate in the study (100%) and 1317 divers (94.8%) who fully completed the questionnaire were included in the analysis. Of these 1317 individuals, 96 (7.3%) suffered from at least 1 episode of barodontalgia while diving, with a total of 119 episodes of barodontalgia. Barodontalgia was more frequent in the upper (62.2%) than the lower dentition (37.8%) (OR = 2.7; 95% CI, 1.6-4.5) and appeared more common during descent (77.3%) than ascent (22.7%) (OR = 11.6; 95% CI, 6.3-31.3). Barodontalgia experience was higher in divers who have an examination less than once per year (14.5%) in comparison to divers who usually have a dental examination once a year or more (6.3%) (OR = 2.5; 95% CI, 1.5-4.2). Barodontalgia mostly appeared in the maxilla and during descent; therefore, a great role for barosinusitis in the etiology of oral pain while diving may be suggested. The infrequent experience of barodontalgia in divers who routinely visit the dentist once a year or more suggests that the risk of barodontalgia might decrease with the maintenance of a good oral status.

Back pain and degenerative abnormalities in the spine of young elite divers: a 5-year follow-up magnetic resonance imaging study.

PubMed

Baranto, Adad; Hellström, Mikael; Nyman, Rickard; Lundin, Olof; Swärd, Leif

2006-09-01

Several studies have been published on disc degeneration among young athletes in sports with great demands on the back, but few on competitive divers; however, there are no long-term follow-up studies. Twenty elite divers between 10 and 21 years of age, with the highest possible national ranking, were selected at random without knowledge of previous or present back injuries or symptoms for an MRI study of the thoraco-lumbar spine in a 5-year longitudinal study. The occurrence of MRI abnormalities and their correlation with back pain were evaluated. Eighty-nine percent of the divers had a history of back pain and the median age at the first episode of back pain was 15 years. Sixty-five percent of the divers had MRI abnormalities in the thoraco-lumbar spine already at baseline. Only one diver without abnormalities at baseline had developed abnormalities at follow-up. Deterioration of any type of abnormality was found in 9 of 17 (53%) divers. Including all disc levels in all divers, the total number of abnormalities increased by 29% at follow-up, as compared to baseline. The most common abnormalities were reduced disc signal, Schmorl's nodes, and disc height reduction. Since almost all divers had previous or present back pain, a differentiated analysis of the relationship between pain and MRI findings was not possible. However, the high frequency of both back pain and MRI changes suggests a causal relationship. In conclusion, elite divers had high frequency of back pain at young ages and they run a high risk of developing degenerative abnormalities of the thoraco-lumbar spine, probably due to injuries to the spine during the growth spurt.

Carotid duplex ultrasound and transcranial Doppler findings in commercial divers and pilots.

PubMed

Dormanesh, Banafshe; Vosoughi, Kia; Akhoundi, Fahimeh H; Mehrpour, Masoud; Fereshtehnejad, Seyed-Mohammad; Esmaeili, Setareh; Sabet, Azin Shafiee

2016-12-01

The risky working environments of divers and pilots, and the possible role of extreme ambient pressure in carotid stenosis, make ischemic stroke an important occupational concern among these professionals. In this study, we aimed to evaluate the association of being exposed to hyperbaric or hypobaric conditions with carotid artery stenosis by comparing common carotid intima-media thickness (CCIMT) and blood flow velocities of cerebral arteries in divers and pilots using carotid duplex ultrasound (CDUS) and transcranial Doppler (TCD). CDUS and transtemporal TCD were performed in 29 divers, 36 pilots and 30 control participants. Medical history, blood pressure, lipid profile and blood sugar were recorded to control the previously well-known risk factors of atherosclerosis. Findings of the CDUS and TCD [including: CCIMT and blood flow velocities of internal carotid artery (ICA), common carotid artery (CCA), and middle cerebral artery (MCA)] of divers and pilots were compared with those of the control group using regression analysis models. Both right and left side CCIMT were significantly higher in divers (P < 0.05) and pilots (P < 0.05) in comparison with the control group. Carotid index [peak systolic velocity (PSV) of ICA/PSV of CCA) of divers and pilots were also higher than the control group. TCD findings were not significantly different between divers, pilots, and the control group. Increased CCIMT and carotid index in diver and pilot groups appear to be suggestive of accelerated atherosclerosis of carotid artery in these occupational groups.

46 CFR 71.50-27 - Alternative Hull Examination (AHE) program options: Divers or underwater remotely operated...

Code of Federal Regulations, 2011 CFR

2011-10-01

... accuracy; (3) Take ultrasonic thickness gaugings at a minimum of 5 points on each plate, evenly spaced; (4... must be accepted by the Officer in Charge, Marine Inspection (OCMI) prior to the survey. If you choose...

46 CFR 71.50-27 - Alternative Hull Examination (AHE) program options: Divers or underwater remotely operated...

Code of Federal Regulations, 2013 CFR

2013-10-01

... accuracy; (3) Take ultrasonic thickness gaugings at a minimum of 5 points on each plate, evenly spaced; (4... must be accepted by the Officer in Charge, Marine Inspection (OCMI) prior to the survey. If you choose...

46 CFR 71.50-27 - Alternative Hull Examination (AHE) program options: Divers or underwater remotely operated...

Code of Federal Regulations, 2012 CFR

2012-10-01

... accuracy; (3) Take ultrasonic thickness gaugings at a minimum of 5 points on each plate, evenly spaced; (4... must be accepted by the Officer in Charge, Marine Inspection (OCMI) prior to the survey. If you choose...

46 CFR 71.50-27 - Alternative Hull Examination (AHE) program options: Divers or underwater remotely operated...

Code of Federal Regulations, 2014 CFR

2014-10-01

... accuracy; (3) Take ultrasonic thickness gaugings at a minimum of 5 points on each plate, evenly spaced; (4... must be accepted by the Officer in Charge, Marine Inspection (OCMI) prior to the survey. If you choose...

36 CFR 3.18 - May I snorkel or underwater dive in park waters?

Code of Federal Regulations, 2011 CFR

2011-07-01

..., DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.18 May I snorkel or underwater dive in park... open to the use of vessels, a diver must prominently display a dive flag during dive operations. A dive...

36 CFR 3.18 - May I snorkel or underwater dive in park waters?

Code of Federal Regulations, 2010 CFR

2010-07-01

..., DEPARTMENT OF THE INTERIOR BOATING AND WATER USE ACTIVITIES § 3.18 May I snorkel or underwater dive in park... open to the use of vessels, a diver must prominently display a dive flag during dive operations. A dive...

Evaluating the attractiveness and effectiveness of artificial coral reefs as a recreational ecosystem service.

PubMed

Belhassen, Yaniv; Rousseau, Meghan; Tynyakov, Jenny; Shashar, Nadav

2017-12-01

Artificial reefs are increasingly being used around the globe to attract recreational divers, for both environmental and commercial reasons. This paper examines artificial coral reefs as recreational ecosystem services (RES) by evaluating their attractiveness and effectiveness and by examining divers' attitudes toward them. An online survey targeted at divers in Israel (n = 263) indicated that 35% of the dives in Eilat (a resort city on the shore of the Red Sea) take place at artificial reefs. A second study monitored divers' behavior around the Tamar artificial reef, one of the most popular submerged artificial reefs in Eilat, and juxtaposed it with divers' activities around two adjacent natural reefs. Findings show that the average diver density at the artificial reef was higher than at the two nearby natural knolls and that the artificial reef effectively diverts divers from natural knolls. A third study that examined the attitudes towards natural vs. artificial reefs found that the artificial reefs are considered more appropriate for training, but that divers feel less relaxed around them. By utilizing the RES approach as a framework, the study offers a comprehensive methodology that brings together the aesthetic, behavioral, and attitudinal aspects in terms of which artificial reefs can be evaluated. Copyright © 2017 Elsevier Ltd. All rights reserved.

Underwater Acoustic Source Localisation Among Blind and Sighted Scuba Divers: Comparative study.

PubMed

Cambi, Jacopo; Livi, Ludovica; Livi, Walter

2017-05-01

Many blind individuals demonstrate enhanced auditory spatial discrimination or localisation of sound sources in comparison to sighted subjects. However, this hypothesis has not yet been confirmed with regards to underwater spatial localisation. This study therefore aimed to investigate underwater acoustic source localisation among blind and sighted scuba divers. This study took place between February and June 2015 in Elba, Italy, and involved two experimental groups of divers with either acquired (n = 20) or congenital (n = 10) blindness and a control group of 30 sighted divers. Each subject took part in five attempts at an under-water acoustic source localisation task, in which the divers were requested to swim to the source of a sound originating from one of 24 potential locations. The control group had their sight obscured during the task. The congenitally blind divers demonstrated significantly better underwater sound localisation compared to the control group or those with acquired blindness ( P = 0.0007). In addition, there was a significant correlation between years of blindness and underwater sound localisation ( P <0.0001). Congenital blindness was found to positively affect the ability of a diver to recognise the source of a sound in an underwater environment. As the correct localisation of sounds underwater may help individuals to avoid imminent danger, divers should perform sound localisation tests during training sessions.

Recreational Diver Behavior and Contacts with Benthic Organisms in the Abrolhos National Marine Park, Brazil

NASA Astrophysics Data System (ADS)

Giglio, Vinicius J.; Luiz, Osmar J.; Schiavetti, Alexandre

2016-03-01

In the last two decades, coral reefs have become popular among recreational divers, especially inside marine protected areas. However, the impact caused by divers on benthic organisms may be contributing to the degradation of coral reefs. We analyzed the behavior of 142 scuba divers in the Abrolhos National Marine Park, Brazil. We tested the effect of diver profile, reef type, use of additional equipment, timing, and group size on diver behavior and their contacts with benthic organisms. Eighty-eight percent of divers contacted benthic organism at least once, with an average of eight touches and one damage per dive. No significant differences in contacts were verified among gender, group size, or experience level. Artificial reef received a higher rate of contact than pinnacle and fringe reefs. Specialist photographers and sidemount users had the highest rates, while non-users of additional equipment and mini camera users had the lowest contact rates. The majority of contacts were incidental and the highest rates occurred in the beginning of a dive. Our findings highlight the need of management actions, such as the provision of pre-dive briefing including ecological aspects of corals and beginning dives over sand bottoms or places with low coral abundance. Gathering data on diver behavior provides managers with information that can be used for tourism management.

Recreational Diver Behavior and Contacts with Benthic Organisms in the Abrolhos National Marine Park, Brazil.

PubMed

Giglio, Vinicius J; Luiz, Osmar J; Schiavetti, Alexandre

2016-03-01

In the last two decades, coral reefs have become popular among recreational divers, especially inside marine protected areas. However, the impact caused by divers on benthic organisms may be contributing to the degradation of coral reefs. We analyzed the behavior of 142 scuba divers in the Abrolhos National Marine Park, Brazil. We tested the effect of diver profile, reef type, use of additional equipment, timing, and group size on diver behavior and their contacts with benthic organisms. Eighty-eight percent of divers contacted benthic organism at least once, with an average of eight touches and one damage per dive. No significant differences in contacts were verified among gender, group size, or experience level. Artificial reef received a higher rate of contact than pinnacle and fringe reefs. Specialist photographers and sidemount users had the highest rates, while non-users of additional equipment and mini camera users had the lowest contact rates. The majority of contacts were incidental and the highest rates occurred in the beginning of a dive. Our findings highlight the need of management actions, such as the provision of pre-dive briefing including ecological aspects of corals and beginning dives over sand bottoms or places with low coral abundance. Gathering data on diver behavior provides managers with information that can be used for tourism management.

Possible central nervous system oxygen toxicity seizures among US recreational air or enriched air nitrox open circuit diving fatalities 2004-2013.

PubMed

Buzzacott, P; Denoble, P J

2017-01-01

The first diver certification programme for recreational 'enriched air nitrox' (EAN) diving was released in 1985. Concerns were expressed that many EAN divers might suffer central nervous system (CNS) oxygen toxicity seizures and drown. US fatalities on open-circuit scuba occurring between 2004-2013, where the breathing gas was either air or EAN, were identified. Causes of death and preceding circumstances were examined by a medical examiner experienced in diving autopsies. Case notes were searched for witnessed seizures at elevated partial pressures of oxygen. The dataset comprised 344 air divers (86%) and 55 divers breathing EAN (14%). EAN divers' fatal dives were deeper than air divers' (28 msw vs 18 msw, p < 0.0001). Despite this, of the 249 cases where a cause of death was established, only three EAN divers were considered to have possibly died following CNS oxygen toxicity seizures at depth (ppO2 132, 142 and 193 kPa). The analysis of recreational diving fatalities in the US over 10 years found just one death likely from CNS oxygen toxicity among EAN divers. A further two possible, although unlikely, cases were also found. Fears of commonplace CNS oxygen toxicity seizures while EAN diving have not apparently been realized.

Diver Relative UUV Navigation for Joint Human-Robot Operations

DTIC Science & Technology

2013-09-01

loop response: (10) where Kej is the gain that scales the position error to force . Substituting the measured values for ζ and ων as well as the...Underwater Vehicle; Tethered ; Hovering; Autonomous Underwater Vehicle; Joint human-robot operations; dynamic, uncertain environments 15. NUMBER OF PAGES...4   Figure 3.   The SeaBotix vLBV300 tethered AUV platform (left), and the planar vectored thruster

Brain MRI signal abnormalities and right-to-left shunting in asymptomatic military divers.

PubMed

Gempp, Emmanuel; Sbardella, Fabrice; Stephant, Eric; Constantin, Pascal; De Maistre, Sebastien; Louge, Pierre; Blatteau, Jean-Eric

2010-11-01

We conducted a controlled study to assess the prevalence of brain MRI hyperintense signals and their correlation with right-to-left shunting (RLS) in military divers. We prospectively enrolled 32 asymptomatic military divers under 41 yr of age and 32 non-diving healthy subjects matched with respect to age and vascular disease risk factors. We examined both groups with a 3-Tesla brain MRI; RLS was detected using transcranial pulsed Doppler in divers only. Hyperintense spots were observed in 43.7% of the divers and 21.8% of the control subjects. In particular, divers with significant shunting exhibited a higher prevalence of hyperintensities compared to those with slight or no RLS (75% vs. 25%, respectively). Linear trend analysis also revealed a positive correlation between focal white matter changes, determined using a validated visual rating scale and the RLS grade. Healthy military divers with a hemodynamically relevant RLS have an increased likelihood of cerebral hyperintense spots compared to age-matched normal subjects. The clinical relevance of these MRI signal abnormalities and their causal relationship with diving remain unclear.

A Mathematical Model to Predict and Maintain the Neutral Buoyancy of Suited Astronauts

NASA Technical Reports Server (NTRS)

Clowers, Kurt; Jaramillo, Marcos; Nguyen, Daniel; Sweet, Robert; Rajulu, Sudhakar

2006-01-01

A previous study reported that inadequate weigh outs of suited subjects contribute to fatigue and the risk of injury during training in the Neutral Buoyancy Laboratory (NBL). Another study suggested that shoulder injuries observed in suited subjects who train in the NBL may be attributed to excessive righting moments caused by a non-optimal weigh out. The purpose of this study was to develop a mathematical model to predict and maintain the neutral buoyancy of suited subjects during training operations at the NBL. Due to time constraints, one certified NBL support diver served as a subject (height: 66.54 in; weight: 182 lbs) for this study and only one complete test was conducted. The study was divided into two runs for which the first run required the NBL divers to perform a weigh out similar to a suited astronaut on a scuba diver wearing a mock Portable Life Support System and a Displays and Control Module. For the second run, the same subject and equipment were weighed out according to the mathematical model. The objective of each run was to achieve a neutrally buoyant subject floating 450 to the pool floor. Motion data was collected using two underwater cameras and analyzed using Dartfish video analysis software while force and moment data were recorded using an AMTI force plate. The results from the NBL divers visual run indicate that the subject was floating at an angle of 29.50 while the resultant force and moment data were 1.139 lb and 1.125 ft-lb respectively. The mathematical model s weigh out resulted in the subject floating at an angle of 37.40 and a resultant force of 0.765 lb and resultant moment of 1.248 ft-lb. The mathematical model was better able to orient the subject and reduce resultant moment and force as compared to the NBL divers.

Low power integrated pumping and valving arrays for microfluidic systems

DOEpatents

Krulevitch, Peter A [Pleasanton, CA; Benett, William J [Livermore, CA; Rose, Klint A [Livermore, CA; Hamilton, Julie [Tracy, CA; Maghribi, Mariam [Davis, CA

2006-04-11

Low power integrated pumping and valving arrays which provide a revolutionary approach for performing pumping and valving approach for performing pumping and valving operations in microfabricated fluidic systems for applications such as medical diagnostic microchips. Traditional methods rely on external, large pressure sources that defeat the advantages of miniaturization. Previously demonstrated microfabrication devices are power and voltage intensive, only function at sufficient pressure to be broadly applicable. This approach integrates a lower power, high-pressure source with a polymer, ceramic, or metal plug enclosed within a microchannel, analogous to a microsyringe. When the pressure source is activated, the polymer plug slides within the microchannel, pumping the fluid on the opposite side of the plug without allowing fluid to leak around the plug. The plugs also can serve as microvalves.

Piezoelectric valve

DOEpatents

Petrenko, Serhiy Fedorovich

2013-01-15

A motorized valve has a housing having an inlet and an outlet to be connected to a pipeline, a saddle connected with the housing, a turn plug having a rod, the turn plug cooperating with the saddle, and a drive for turning the valve body and formed as a piezoelectric drive, the piezoelectric drive including a piezoelectric generator of radially directed standing acoustic waves, which is connected with the housing and is connectable with a pulse current source, and a rotor operatively connected with the piezoelectric generator and kinematically connected with the rod of the turn plug so as to turn the turn plug when the rotor is actuated by the piezoelectric generator.

Design and Testing of a Diver Thermal Protection Garment

DTIC Science & Technology

2008-05-01

Felske JD.. Bardy E., Cuviello R. , Walcztk J ., Reynolds D and Janish J and their citations are shown below. The extensive evaluation of the thermal...indefinitely which we have demonstrate in a few divers. We have performed these tests in resting divers ( Bardy et al 2007) and in exercising divers...PUBLICATIONS: 1. Felske JD. Effective thermal conductivity of composite spheres in a continuous medium with contact resistance. Int J Heat & Mass Transfer 47

KSC-02pd1302

NASA Image and Video Library

2002-09-11

KENNEDY SPACE CENTER, FLA. -- An Air Care team from Orlando take a distressed lobster diver to the helicopter to take him to Florida Hospital. The diver was picked up by the Freedom Star, one of the Shuttle Rocket Booster retrieval ships, on a certification exercise and near the location of a lobster diving boat that radioed the U.S. Coast Guard for help when one of the divers experienced difficulty breathing on his return to the surface. Hearing the call for help, the captain of the Freedom Star offered to help. The ship had a dive team on board, including a diver medical technician, Andy Fish, as well as a hyperbaric chamber. Fish stayed with the diver in the recompression chamber aboard the Freedom Star until the ship reached Port Canaveral where a KSC Occupational Health doctor waited. The diver was stabilized and then taken to Florida Hospital.

KSC-02pd1301

NASA Image and Video Library

2002-09-11

KENNEDY SPACE CENTER, FLA. - United Space Alliance workers on board the Freedom Star, one of the Shuttle Rocket Booster retrieval ships, release a distressed lobster diver to an Air Care Team from Orlando for transfer to a hospital. The ship and its dive team, including a diver medical technician, Andy Fish, were instrumental in rescuing the diver off Cape Canaveral Sept. 11. The ship was on a certification exercise and near the location of a lobster diving boat that radioed the U.S. Coast Guard for help when one of the divers experienced difficulty breathing on his return to the surface. Hearing the call for help, the captain of the Freedom Star offered to help. Fish stayed with the diver in the recompression chamber aboard the Freedom Star until the ship reached Port Canaveral where a KSC Occupational Health doctor waited. The diver was stabilized and then taken to Florida Hospital.

46 CFR 197.450 - Breathing gas tests.

Code of Federal Regulations, 2010 CFR

2010-10-01

... taken at the connection point to the distribution system— (1) Every 6 months; and (2) After every repair or modification. (b) Purchased supplies of breathing mixtures supplied to a diver are checked before... commencement of diving operations, at the umbilical or underwater breathing apparatus connection point for the...

30 CFR 250.1727 - What information must I include in my final application to remove a platform or other facility?

Code of Federal Regulations, 2010 CFR

2010-07-01

... MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER... are placing the explosives inside or outside of the pilings; (3) If you will use divers or acoustic...

Sponge divers of the Aegean and medical consequences of risky compressed-air dive profiles.

PubMed

Toklu, Akin Savas; Cimsit, Maide

2009-04-01

Historically, Turkey once had a substantial number of professional sponge divers, a population known for a relatively high incidence of diving-related conditions such as decompression sickness (DCS) and dysbaric osteonecrosis (DON). Sponge diving ended in the mid-1980s when nearly all of the sponges in the Aegean and Mediterranean Seas contracted a bacterial disease and the occupation became unprofitable. We reviewed the records of Turkish sponge divers for information on their level of knowledge, diving equipment, dive profiles, and occupational health problems. Information was collected by: 1) interviewing former sponge divers near Bodrum, where most of them had settled; 2) reviewing the relevant literature; and 3) examining the medical records of sponge divers who underwent recompression treatment. These divers used three types of surface-supplied equipment, including hard helmets, Fernez apparatus, and hookahs; the latter were preferred because they allowed divers the greatest freedom of movement while harvesting sponges underwater. These divers used profiles that we now know involved a high risk for DCS and DON. We were able to access the records of 58 divers who had received recompression treatment. All of the cases involved severe DCS and delays from dive to recompression that averaged 72 h. Complete resolution of symptoms occurred in only 11 cases (19%). Thus, we were able to document the several factors that contributed to the risks in this occupational group, including unsafe dive profiles, resistance to seeking treatment, long delays before recompression, and the fact that recompression treatment used air rather than oxygen.

A Framework for Managing Diver Impacts on Historic Shipwrecks

NASA Astrophysics Data System (ADS)

Edney, Joanne

2016-12-01

Shipwrecks are becoming increasingly popular and, therefore important attractions for recreational scuba divers. Divers' usage of these sites has the potential to create a range of adverse impacts on their cultural heritage values. Impacts associated with recreational scuba diving include boat anchor and mooring damage, impairment of site integrity and stability, the effects of intentional and unintentional contact with shipwrecks and artifacts, as well as divers' exhaled air bubbles coming into contact with shipwrecks. While these consequences may not present a major threat in comparison to other human impacts, such as fishing activities, extractive industries or commercial salvage, their cumulative effect can be significant, particularly at sites where visitation levels are high. Unlike natural events such as storms, diver impacts can be controlled and managing these impacts is an important component of a heritage management strategy for any site. Heritage managers face the difficult challenge of, on the one hand, balancing divers' access to important underwater cultural heritage sites, and on the other hand, protecting these sites. This paper outlines the causes and nature of potential recreational diver impacts on shipwrecks, briefly describing a range of management approaches that can mitigate such impacts, and presents a framework for the management of diver impacts on cultural heritage values of historic shipwrecks. The framework is designed to assist managers in deciding on appropriate management actions and priorities for particular sites.

Underwater Acoustic Source Localisation Among Blind and Sighted Scuba Divers

PubMed Central

Cambi, Jacopo; Livi, Ludovica; Livi, Walter

2017-01-01

Objectives Many blind individuals demonstrate enhanced auditory spatial discrimination or localisation of sound sources in comparison to sighted subjects. However, this hypothesis has not yet been confirmed with regards to underwater spatial localisation. This study therefore aimed to investigate underwater acoustic source localisation among blind and sighted scuba divers. Methods This study took place between February and June 2015 in Elba, Italy, and involved two experimental groups of divers with either acquired (n = 20) or congenital (n = 10) blindness and a control group of 30 sighted divers. Each subject took part in five attempts at an under-water acoustic source localisation task, in which the divers were requested to swim to the source of a sound originating from one of 24 potential locations. The control group had their sight obscured during the task. Results The congenitally blind divers demonstrated significantly better underwater sound localisation compared to the control group or those with acquired blindness (P = 0.0007). In addition, there was a significant correlation between years of blindness and underwater sound localisation (P <0.0001). Conclusion Congenital blindness was found to positively affect the ability of a diver to recognise the source of a sound in an underwater environment. As the correct localisation of sounds underwater may help individuals to avoid imminent danger, divers should perform sound localisation tests during training sessions. PMID:28690888

Fast-Acting Valve

NASA Technical Reports Server (NTRS)

Wojciechowski, Bogdan V. (Inventor); Pegg, Robert J. (Inventor)

2003-01-01

A fast-acting valve includes an annular valve seat that defines an annular valve orifice between the edges of the annular valve seat, an annular valve plug sized to cover the valve orifice when the valve is closed, and a valve-plug holder for moving the annular valve plug on and off the annular valve seat. The use of an annular orifice reduces the characteristic distance between the edges of the valve seat. Rather than this distance being equal to the diameter of the orifice, as it is for a conventional circular orifice, the characteristic distance equals the distance between the inner and outer radii (for a circular annulus). The reduced characteristic distance greatly reduces the gap required between the annular valve plug and the annular valve seat for the valve to be fully open, thereby greatly reducing the required stroke and corresponding speed and acceleration of the annular valve plug. The use of a valve-plug holder that is under independent control to move the annular valve plug between its open and closed positions is important for achieving controllable fast operation of the valve.

Functional response of sport divers to lobsters with application to fisheries management.

PubMed

Eggleston, David B; Parsons, Darren M; Kellison, G Todd; Plaia, Gayle R; Johnson, Eric G

2008-01-01

Fishery managers must understand the dynamics of fishers and their prey to successfully predict the outcome of management actions. We measured the impact of a two-day exclusively recreational fishery on Caribbean spiny lobster in the Florida Keys, USA, over large spatial scales (>100 km) and multiple years and used a theoretical, predator-prey functional response approach to identify whether or not sport diver catch rates were density-independent (type I) or density-dependent (type II or III functional response), and if catch rates were saturated (i.e., reached an asymptote) at relatively high lobster densities. We then describe how this predator-prey framework can be applied to fisheries management for spiny lobster and other species. In the lower Keys, divers exhibited a type-I functional response, whereby they removed a constant and relatively high proportion of lobsters (0.74-0.84) across all pre-fishing-season lobster densities. Diver fishing effort increased in a linear manner with lobster prey densities, as would be expected with a type-I functional response, and was an order of magnitude lower in the upper Keys than lower Keys. There were numerous instances in the upper Keys where the density of lobsters actually increased from before to after the fishing season, suggesting some type of "spill-in effect" from surrounding diver-disturbed areas. With the exception of isolated reefs in the upper Keys, the proportion of lobsters removed by divers was density independent (type-I functional response) and never reached saturation at natural lobster densities. Thus, recreational divers have a relatively simple predatory response to spiny lobster, whereby catch rates increase linearly with lobster density such that catch is a reliable indicator of abundance. Although diver predation is extremely high (approximately 80%), diver predation pressure is not expected to increase proportionally with a decline in lobster density (i.e., a depensatory response), which could exacerbate local extinction. Furthermore, management actions that reduce diver effort should have a concomitant and desired reduction in catch. The recreational diver-lobster predator-prey construct in this study provides a useful predictive framework to apply to both recreational and commercial fisheries, and on which to build as management actions are implemented.

Preliminary Investigation of Methods to Increase Base Pressure of Plug Nozzles at Mach 0.9

NASA Technical Reports Server (NTRS)

Salmi, Reino J

1956-01-01

The effects of various afterbody changes on the base pressure of a nacelle-type isentropic plug nozzle installation operating at lower-than-design jet pressure ratios were investigated at a Mach number of 0.9. Although the estimates of the net propulsive force contain some uncertainties, the results indicate that both a plain-ring base shroud and a circular-arc boattail fairing reduced the loss in net propulsive force experienced with a cylindrical nacelle installation of the plug nozzle.

[APPLICATION OF FISTULA PLUG WITH THE FIBRIN ADHESIVE IN TREATMENT OF RECTAL FISTULAS].

PubMed

Aydinova, P R; Aliyev, E A

2015-05-01

Results of surgical treatment of 21 patients, suffering high transsphincteric and extrasphincteric rectal fistulas, were studied. In patients of Group I the fistula passage was closed, using fistula plug obturator; and in patients of Group II--by the same, but preprocessed by fibrin adhesive. The fistula aperture germeticity, prophylaxis of rude cicatrices development in operative wound zone, promotion of better fixation of bioplastic material were guaranteed, using fistula plug obturator with preprocessing, using fibrin adhesive.

The Role of PWC in Declaring a Diver Fit

DTIC Science & Technology

2001-06-01

Conditions [les Questions medicales a caractere oprationel liees aux conditions hypobares ou hyperbares ] To order the complete compilation report...Approved for public release, distribution unlimited This paper is part of the following report: TITLE: Operational Medical Issues in Hypo-and Hyperbaric ...on "Operational Medical Issues in Hypo- and Hyperbaric Conditions", held in Toronto, Canada, 16-19 October 2000, and published in RTO MP-062. 18-2

46 CFR 176.600 - Drydock and internal structural examination intervals.

Code of Federal Regulations, 2010 CFR

2010-10-01

... States port, it must undergo the required examination before sailing. (c) If your vessel is not operated... exclusively by divers, the vessel must undergo two alternate hull exams and two internal structural exams within any five-year period. If a vessel completes a satisfactory alternate hull exam, with the...

Visual observation of fishes and aquatic habitat [Chapter 17

Treesearch

Russell F. Thurow; C. Andrew Dolloff; J. Ellen Marsden

2012-01-01

Whether accomplished above the water surface or performed underwater by snorkel, scuba, or hookah divers or remotely operated vehicles (ROVs); direct observation techniques are among the most effective means for obtaining accurate and often unique information on aquatic organisms in their natural surroundings. Many types of studies incorporate direct observation...

75 FR 33241 - Submission for OMB Review; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2010-06-11

... submit to the Office of Management and Budget (OMB) for clearance the following proposal for collection... information gained will be used to develop management strategies and an outreach and education plan intended..., surfers, beach goers, divers, operators and patrons of commercial water sports tours, and hotel managers...

Nozzle dam having a unitary plug

DOEpatents

Veronesi, L.; Wepfer, R.M.

1992-12-15

Apparatus for sealing the primary-side coolant flow nozzles of a nuclear steam generator is disclosed. The steam generator has relatively small diameter manway openings for providing access to the interior of the steam generator including the inside surface of each nozzle, the manway openings having a diameter substantially less than the inside diameter of each nozzle. The apparatus includes a bracket having an outside surface for matingly sealingly engaging the inside surface of the nozzle. The bracket also has a plurality of openings longitudinally therethrough and a plurality of slots transversely therein in communication with each opening. A plurality of unitary plugs sized to pass through the manway opening are matingly sealingly disposed in each opening of the bracket for sealingly plugging each opening. Each plug includes a plurality of arms operable to engage the slots of the bracket for connecting each plug to the bracket, so that the nozzle is sealed as the plugs seal the openings and are connected to the bracket. 16 figs.

Nozzle dam having a unitary plug

DOEpatents

Veronesi, Luciano; Wepfer, Robert M.

1992-01-01

Apparatus for sealing the primary-side coolant flow nozzles of a nuclear steam generator. The steam generator has relatively small diameter manway openings for providing access to the interior of the steam generator including the inside surface of each nozzle, the manway openings having a diameter substantially less than the inside diameter of each nozzle. The apparatus includes a bracket having an outside surface for matingly sealingly engaging the inside surface of the nozzle. The bracket also has a plurality of openings longitudinally therethrough and a plurality of slots transversely therein in communication with each opening. A plurality of unitary plugs sized to pass through the manway opening are matingly sealingly disposed in each opening of the bracket for sealingly plugging each opening. Each plug includes a plurality of arms operable to engage the slots of the bracket for connecting each plug to the bracket, so that the nozzle is sealed as the plugs seal the openings and are connected to the bracket.

Association of microparticles and neutrophil activation with decompression sickness.

PubMed

Thom, Stephen R; Bennett, Michael; Banham, Neil D; Chin, Walter; Blake, Denise F; Rosen, Anders; Pollock, Neal W; Madden, Dennis; Barak, Otto; Marroni, Alessandro; Balestra, Costantino; Germonpre, Peter; Pieri, Massimo; Cialoni, Danilo; Le, Phi-Nga Jeannie; Logue, Christopher; Lambert, David; Hardy, Kevin R; Sward, Douglas; Yang, Ming; Bhopale, Veena B; Dujic, Zeljko

2015-09-01

Decompression sickness (DCS) is a systemic disorder, assumed due to gas bubbles, but additional factors are likely to play a role. Circulating microparticles (MPs)--vesicular structures with diameters of 0.1-1.0 μm--have been implicated, but data in human divers have been lacking. We hypothesized that the number of blood-borne, Annexin V-positive MPs and neutrophil activation, assessed as surface MPO staining, would differ between self-contained underwater breathing-apparatus divers suffering from DCS vs. asymptomatic divers. Blood was analyzed from 280 divers who had been exposed to maximum depths from 7 to 105 meters; 185 were control/asymptomatic divers, and 90 were diagnosed with DCS. Elevations of MPs and neutrophil activation occurred in all divers but normalized within 24 h in those who were asymptomatic. MPs, bearing the following proteins: CD66b, CD41, CD31, CD142, CD235, and von Willebrand factor, were between 2.4- and 11.7-fold higher in blood from divers with DCS vs. asymptomatic divers, matched for time of sample acquisition, maximum diving depth, and breathing gas. Multiple logistic regression analysis documented significant associations (P < 0.001) between DCS and MPs and for neutrophil MPO staining. Effect estimates were not altered by gender, body mass index, use of nonsteroidal anti-inflammatory agents, or emergency oxygen treatment and were modestly influenced by divers' age, choice of breathing gas during diving, maximum diving depth, and whether repetitive diving had been performed. There were no significant associations between DCS and number of MPs without surface proteins listed above. We conclude that MP production and neutrophil activation exhibit strong associations with DCS. Copyright © 2015 the American Physiological Society.

Reef fish communities are spooked by scuba surveys and may take hours to recover

PubMed Central

Cheal, Alistair J.; Miller, Ian R.

2018-01-01

Ecological monitoring programs typically aim to detect changes in the abundance of species of conservation concern or which reflect system status. Coral reef fish assemblages are functionally important for reef health and these are most commonly monitored using underwater visual surveys (UVS) by divers. In addition to estimating numbers, most programs also collect estimates of fish lengths to allow calculation of biomass, an important determinant of a fish’s functional impact. However, diver surveys may be biased because fishes may either avoid or are attracted to divers and the process of estimating fish length could result in fish counts that differ from those made without length estimations. Here we investigated whether (1) general diver disturbance and (2) the additional task of estimating fish lengths affected estimates of reef fish abundance and species richness during UVS, and for how long. Initial estimates of abundance and species richness were significantly higher than those made on the same section of reef after diver disturbance. However, there was no evidence that estimating fish lengths at the same time as abundance resulted in counts different from those made when estimating abundance alone. Similarly, there was little consistent bias among observers. Estimates of the time for fish taxa that avoided divers after initial contact to return to initial levels of abundance varied from three to 17 h, with one group of exploited fishes showing initial attraction to divers that declined over the study period. Our finding that many reef fishes may disperse for such long periods after initial contact with divers suggests that monitoring programs should take great care to minimise diver disturbance prior to surveys. PMID:29844998

Cerebral magnetic resonance imaging of compressed air divers in diving accidents.

PubMed

Gao, G K; Wu, D; Yang, Y; Yu, T; Xue, J; Wang, X; Jiang, Y P

2009-01-01

To investigate the characteristics of the cerebral magnetic resonance imaging (MRI) of compressed air divers in diving accidents, we conducted an observational case series study. MRI of brain were examined and analysed on seven cases compressed air divers complicated with cerebral arterial gas embolism CAGE. There were some characteristics of cerebral injury: (1) Multiple lesions; (2) larger size; (3) Susceptible to parietal and frontal lobe; (4) Both cortical grey matter and subcortical white matter can be affected; (5) Cerebellum is also the target of air embolism. The MRI of brain is an sensitive method for detecting cerebral lesions in compressed air divers in diving accidents. The MRI should be finished on divers in diving accidents within 5 days.

Can Artificial Reef Wrecks Reduce Diver Impacts on Shipwrecks? The Management Dimension

NASA Astrophysics Data System (ADS)

Edney, Joanne; Spennemann, Dirk H. R.

2015-08-01

Managers have been advocating the use of artificial reef wrecks to diversify the experiences of recreational divers and thereby reduce the well-known impact on reefs. To examine whether artificial reef wrecks can serve as substitutes for historic shipwrecks this paper discusses the attitude of Australian divers to wreck diving in general and to artificial reef wrecks in particular. While the overwhelming majority of divers surveyed accepted the need for control, the experienced divers were less interested in artificial reef wrecks and less prepared to tolerate controls over their perceived freedom to dive wrecks. We present projections that show that this legacy issue will have largely resolved itself by 2025 due to attrition and natural ageing.

40 CFR 86.1816-18 - Emission standards for heavy-duty vehicles.

Code of Federal Regulations, 2014 CFR

2014-07-01

... as specified in this section. (4) Measure emissions from hybrid electric vehicles (including plug-in hybrid electric vehicles) as described in 40 CFR part 1066, subpart F, except that these procedures do not apply for plug-in hybrid electric vehicles during charge-depleting operation. (b) Tier 3 exhaust...

Plug-in Sensors for Air Pollution Monitoring.

ERIC Educational Resources Information Center

Shaw, Manny

Faristors, a type of plug-in sensors used in analyzing equipment, are described in this technical report presented at the 12th Conference on Methods in Air Pollution and Industrial Hygiene Studies, University of Southern California, April, 1971. Their principles of operation, interchangeability, and versatility for measuring air pollution at…

Association between right-to-left shunts and brain lesions in sport divers.

PubMed

Gerriets, Tibo; Tetzlaff, Kay; Hutzelmann, Alfred; Liceni, Thomas; Kopiske, Gerrit; Struck, Niklas; Reuter, Michael; Kaps, Manfred

2003-10-01

Recent studies suggest that healthy sport divers may develop clinically silent brain damage, based on the association between a finding of multiple brain lesions on MRI and the presence of right-to-left shunt, a pathway for venous gas bubbles to enter the arterial system. We performed echocontrast transcranial Doppler sonography in 42 sport divers to determine the presence of a right-to-left shunt. Cranial MRI was carried out using a 1.5 T magnet. A lesion was counted if it was hyperintense on both T2-weighted and T2-weighted fluid attenuated inversion recovery sequences. To test the hypothesis that the occurrence of postdive arterial gas emboli is related to brain lesions on MRI, we measured postdive intravascular bubbles in a subset of 15 divers 30 min after open water scuba dives. Echocontrast transcranial Doppler sonography revealed a right-to-left shunt in 16 of the divers (38%). Only one hyperintensive lesion of the central white matter was found and that was in a diver with no evidence of a right-to-left shunt. Postdive arterial gas emboli were detected in 3 out of 15 divers; they had a right-to-left shunt, but no pathologic findings on cranial magnetic resonance imaging. Our data support the theory that right-to-left shunts can serve as a pathway for venous gas bubbles into the arterial circulation. However, we could not confirm an association between brain lesions and the presence of a right-to-left shunt in sport divers.

Two-Liquid Cartesian Diver

ERIC Educational Resources Information Center

Planinsic, G.; Kos, M.; Jerman, R.

2004-01-01

It is quite easy to make a version of the well known Cartesian diver experiment that uses two immiscible liquids. This allows students to test their knowledge of density and pressure in explaining the diver's behaviour. Construction details are presented here together with a mathematical model to explain the observations.

Demonstration of catalytic combustion with residual fuel

NASA Technical Reports Server (NTRS)

Dodds, W. J.; Ekstedt, E. E.

1981-01-01

An experimental program was conducted to demonstrate catalytic combustion of a residual fuel oil. Three catalytic reactors, including a baseline configuration and two backup configurations based on baseline test results, were operated on No. 6 fuel oil. All reactors were multielement configurations consisting of ceramic honeycomb catalyzed with palladium on stabilized alumina. Stable operation on residual oil was demonstrated with the baseline configuration at a reactor inlet temperature of about 825 K (1025 F). At low inlet temperature, operation was precluded by apparent plugging of the catalytic reactor with residual oil. Reduced plugging tendency was demonstrated in the backup reactors by increasing the size of the catalyst channels at the reactor inlet, but plugging still occurred at inlet temperature below 725 K (845 F). Operation at the original design inlet temperature of 589 K (600 F) could not be demonstrated. Combustion efficiency above 99.5% was obtained with less than 5% reactor pressure drop. Thermally formed NO sub x levels were very low (less than 0.5 g NO2/kg fuel) but nearly 100% conversion of fuel-bound nitrogen to NO sub x was observed.

46 CFR 176.650 - Alternative Hull Examination Program options: Divers or underwater ROV.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Alternative Hull Examination Program options: Divers or...) SMALL PASSENGER VESSELS (UNDER 100 GROSS TONS) INSPECTION AND CERTIFICATION Hull and Tailshaft Examinations § 176.650 Alternative Hull Examination Program options: Divers or underwater ROV. To complete the...

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

PubMed

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.

Inner ear decompression sickness in compressed-air diving.

PubMed

Klingmann, Christoph

2012-01-01

Inner ear decompression sickness (IEDCS) has become more frequently reported in recreational diving. We examined 34 divers after IEDCS and analyzed their dive profiles, pattern of symptoms, time of symptom onset and the association with a right-to left shunt (r/l shunt). Four divers used mixed gas and were excluded from the analysis. Of the remaining 30 divers, 25 presented with isolated IEDCS alone, while five divers had additional skin and neurological symptoms. All divers presented with vertigo (100%), and 12 divers reported additional hearing loss (40%). All symptoms occurred within 120 minutes (median 30 minutes) of ascent. Twenty-two of 30 divers (73.3%) showed a r/l shunt. A possible explanation for the frequent association of a r/l shunt and the dominance of vestibular rather than cochlear symptoms could be attributed to the different blood supply of the inner ear structures and the different size of the labyrinthine compartments. The cochlea has a blood supply up to four times higher than the vestibular part of the inner ear, whereas the vestibular fluid space is 30% larger. The higher prevalence of symptoms referrable to the less well-perfused vestibular organ provides further evidence that persistent local inert gas supersaturation may cause growth of incoming arterial bubbles and may therefore be an important pathophysiological factor in IEDCS.

Ecological carrying capacity assessment of diving site: A case study of Mabul Island, Malaysia.

PubMed

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.

Unconventional nozzle tradeoff study. [space tug propulsion

NASA Technical Reports Server (NTRS)

Obrien, C. J.

1979-01-01

Plug cluster engine design, performance, weight, envelope, operational characteristics, development cost, and payload capability, were evaluated and comparisons were made with other space tug engine candidates using oxygen/hydrogen propellants. Parametric performance data were generated for existing developed or high technology thrust chambers clustered around a plug nozzle of very large diameter. The uncertainties in the performance prediction of plug cluster engines with large gaps between the modules (thrust chambers) were evaluated. The major uncertainty involves, the aerodynamics of the flow from discrete nozzles, and the lack of this flow to achieve the pressure ratio corresponding to the defined area ratio for a plug cluster. This uncertainty was reduced through a cluster design that consists of a plug contour that is formed from the cluster of high area ratio bell nozzles that have been scarfed. Light-weight, high area ratio, bell nozzles were achieved through the use of AGCarb (carbon-carbon cloth) nozzle extensions.

The Effects of Shoaling Internal Tides on Benthic Exchange Events and Near-Boundary Mixing Along the Continental Shelf

DTIC Science & Technology

2013-06-01

Washington headquarters Services, Directorate for Information Operations and Reports, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202...4302, and to the Office of Management and Budget, Paperwork Reduction Project (0704-0188) Washington DC 20503. 1. AGENCY USE ONLY (Leave blank) 2...column currents, turbidity, and turbulence potentially have a large effect on divers and subsurface operating vehicles. Further research is required

The Elimination of Fire Hazard Due to Back Fires

NASA Technical Reports Server (NTRS)

Theodorsen, Theodore; Freeman, Ira M

1933-01-01

A critical study was made of the operation of a type of back-fire arrester used to reduce the fire hazard of aircraft engines. A flame arrester consisting of a pack or plug of alternate flat and corrugated plates of thin metal was installed in the intake pipe of a gasoline engines; an auxiliary spark plug inserted in the intake manifold permitted the production of artificial back fires at will. It was found possible to design a plug which prevented all back fires from reaching the carburetor.

AVTA Federal Fleet PEV Readiness Data Logging and Characterization Study for NASA White Sands Test Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schey, Stephen; Francfort, Jim

This report focuses on the NASA White Sands Test Facility (WSTF) fleet to identify daily operational characteristics of select vehicles and report findings on vehicle and mission characterizations to support the successful introduction of plug-in electric vehicles (PEVs) into the agencies’ fleets. Individual observations of these selected vehicles provide the basis for recommendations related to electric vehicle adoption and whether a battery electric vehicle (BEV) or plug-in hybrid electric vehicle (PHEV) (collectively plug-in electric vehicles, or PEVs) can fulfill the mission requirements.

AVTA Federal Fleet PEV Readiness Data Logging and Characterization Study for National Institute of Health

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schey, Stephen; Francfort, Jim

2014-11-01

This report focuses on the National Institute of Health (NIH) fleet to identify daily operational characteristics of select vehicles and report findings on vehicle and mission characterizations to support the successful introduction of plug-in electric vehicles (PEVs) into the agencies’ fleets. Individual observations of these selected vehicles provide the basis for recommendations related to electric vehicle adoption and whether a battery electric vehicle (BEV) or plug-in hybrid electric vehicle (PHEV) (collectively plug-in electric vehicles, or PEVs) can fulfill the mission requirements.

Coordinating plug-in electric vehicle charging with electric grid: Valley filling and target load following

NASA Astrophysics Data System (ADS)

Zhang, Li; Jabbari, Faryar; Brown, Tim; Samuelsen, Scott

2014-12-01

Plug-in electric vehicles (PEVs) shift energy consumption from petroleum to electricity for the personal transportation sector. This work proposes a decentralized charging protocol for PEVs with grid operators updating the cost signal. Each PEV calculates its own optimal charging profile only once based on the cost signal, after it is plugged in, and sends the result back to the grid operators. Grid operators only need to aggregate charging profiles and update the load and cost. The existing PEV characteristics, national household travel survey (NHTS), California Independent System Operator (CAISO) demand, and estimates for future renewable generation in California are used to simulate PEV operation, PEV charging profiles, grid demand, and grid net load (demand minus renewable). Results show the proposed protocol has good performance for overnight net load valley filling if the costs to be minimized are proportional to the net load. Annual results are shown in terms of overnight load variation and comparisons are made with grid level valley filling results. Further, a target load can be approached in the same manner by using the gap between current load and the target load as the cost. The communication effort involved is quite modest.

40 CFR 146.71 - Closure.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Waste Injection Wells § 146.71 Closure. (a) Closure Plan. The owner or operator of a Class I hazardous waste injection well shall prepare, maintain, and comply with a plan for closure of the well that meets... of material to be used in plugging; (iv) The method of placement of the plugs; (v) Any proposed test...

[Plug-in Based Centralized Control System in Operating Rooms].

PubMed

Wang, Yunlong

2017-05-30

Centralized equipment controls in an operating room (OR) is crucial to an efficient workflow in the OR. To achieve centralized control, an integrative OR needs to focus on designing a control panel that can appropriately incorporate equipment from different manufactures with various connecting ports and controls. Here we propose to achieve equipment integration using plug-in modules. Each OR will be equipped with a dynamic plug-in control panel containing physically removable connecting ports. Matching outlets will be installed onto the control panels of each equipment used at any given time. This dynamic control panel will be backed with a database containing plug-in modules that can connect any two types of connecting ports common among medical equipment manufacturers. The correct connecting ports will be called using reflection dynamics. This database will be updated regularly to include new connecting ports on the market, making it easy to maintain, update, expand and remain relevant as new equipment are developed. Together, the physical panel and the database will achieve centralized equipment controls in the OR that can be easily adapted to any equipment in the OR.

Monitoring diver kinematics with dielectric elastomer sensors

NASA Astrophysics Data System (ADS)

Walker, Christopher R.; Anderson, Iain A.

2017-04-01

Diving, initially motivated for food purposes, is crucial to the oil and gas industry, search and rescue, and is even done recreationally by millions of people. There is a growing need however, to monitor the health and activity of divers. The Divers Alert Network has reported on average 90 fatalities per year since 1980. Furthermore an estimated 1000 divers require recompression treatment for dive-related injuries every year. One means of monitoring diver activity is to integrate strain sensors into a wetsuit. This would provide kinematic information on the diver potentially improving buoyancy control assessment, providing a platform for gesture communication, detecting panic attacks and monitoring diver fatigue. To explore diver kinematic monitoring we have coupled dielectric elastomer sensors to a wetsuit worn by the pilot of a human-powered wet submarine. This provided a unique platform to test the performance and accuracy of dielectric elastomer strain sensors in an underwater application. The aim of this study was to assess the ability of strain sensors to monitor the kinematics of a diver. This study was in collaboration with the University of Auckland's human-powered submarine team, Team Taniwha. The pilot, completely encapsulated in a hull, pedals to propel the submarine forward. Therefore this study focused on leg motion as that is the primary motion of the submarine pilot. Four carbon-filled silicone dielectric elastomer sensors were fabricated and coupled to the pilot's wetsuit. The first two sensors were attached over the knee joints, with the remaining two attached between the pelvis and thigh. The goal was to accurately measure leg joint angles thereby determining the position of each leg relative to the hip. A floating data acquisition unit monitored the sensors and transmitted data packets to a nearby computer for real-time processing. A GoPro Hero 4 silver edition was used to capture the experiments and provide a means of post-validation. The ability of the sensors to measure joint angles was assessed by examining GoPro footage in the image processing software, ImageJ. This paper applies dielectric elastomer sensor technology to monitoring the leg motion of a diver. The experimental set-up and results are presented and discussed.

Three year follow up of a self certification system for the assessment of fitness to dive in Scotland

PubMed Central

Glen, S

2004-01-01

Background: The need for routine medical examinations of sport divers in the Scottish Sub-Aqua Club (Scot-SAC) was revised in March 2000, and a new system using a self administered screening questionnaire was developed to allow divers to be assessed when necessary by doctors with diving medicine experience. Objective: To assess the effect of the new medical system on medical referee workload, diver exclusion rates, and diving incident frequency. Methods: All divers were required to complete a questionnaire to screen for conditions that might affect fitness to dive. Divers answering "Yes" to any of the questions had their medical background assessed by a diving doctor, and, if necessary, received a clinical examination or investigation. The rate of diver exclusions based on the questionnaire response was recorded in conjunction with analysis of the incident reports. Results: The number of forms requiring review by diving doctors increased from 1.2% to 5.7% (p<0.0001, 95% confidence interval (CI) –0.06 to –0.03) in the year after the introduction of the new medical system and gradually increased in subsequent years to 7.7% (p<0.0001, 95% CI –0.08 to –0.05). The number of divers failing to be certified fit to dive increased slightly from 0.7% to 1.0% after one year (p = 0.26, 95% CI –0.01 to 0.00) and subsequently to 2.0% (p = 0.0003, 95% CI 0.02 to –0.01) after three years. Most divers were certified fit to dive on the basis of the questionnaire alone, and only 0.9% required objective investigation (such as exercise testing or echocardiography). Analysis of the incidents during three years of follow up confirmed that no incident occurred because of an undetected pre-existing medical condition. Two incidents involved divers with hypertension, but both had received medical examinations and investigation based on their responses to the questionnaire. Conclusion: The new self administered questionnaire system appears to be an effective screening tool for the detection of divers requiring detailed assessment by doctors with diving medicine experience. PMID:15562174

Effects of external stream flow and afterbody variations on the performance of a plug nozzle

NASA Technical Reports Server (NTRS)

Salmi, R J; Cortright, E M , Jr

1956-01-01

The off-design operation of an isentropic plug nozzle designed for a jet pressure ratio of 15 was investigated experimentally at subsonic Mach numbers up to 0.9 and jet pressure ratios up to 5. When installed in a cylindrical nacelle with a sharp turn at the nozzle lip, the interaction of the jet and the external stream produced low pressures on the base formed by the high lip angle. These low pressures increased the nacelle drag and caused an overexpansion of the jet, which resulted in lower pressures on the plug and, hence, reduced thrust. With a boattail ahead of the plug nozzle, the base pressures were increased and the jet overexpansion significantly reduced.

46 CFR 197.310 - Air compressor system.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 46 Shipping 7 2012-10-01 2012-10-01 false Air compressor system. 197.310 Section 197.310 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.310 Air compressor system. A compressor used to supply breathing air to a diver must have— (a) A volume tank that is— (1) Built and stamped in...

46 CFR 197.310 - Air compressor system.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 46 Shipping 7 2013-10-01 2013-10-01 false Air compressor system. 197.310 Section 197.310 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.310 Air compressor system. A compressor used to supply breathing air to a diver must have— (a) A volume tank that is— (1) Built and stamped in...

Geotechnical Diver Tools Operation and Maintenance Manual

DTIC Science & Technology

1988-10-01

taking a core with the least amount of 4. Screw piston onto bottom of piston rod; disturbance. The piston is unscrewed from lubricate U-packing seal on...corer head onto piston road. 3. Screw piston onto piston rods check U-pecking seal for proper direction (see manual). 4. Slide aore tube over piston and

46 CFR 197.310 - Air compressor system.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 7 2011-10-01 2011-10-01 false Air compressor system. 197.310 Section 197.310 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.310 Air compressor system. A compressor used to supply breathing air to a diver must have— (a) A volume tank that is— (1) Built and stamped in...

46 CFR 197.310 - Air compressor system.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Air compressor system. 197.310 Section 197.310 Shipping... GENERAL PROVISIONS Commercial Diving Operations Equipment § 197.310 Air compressor system. A compressor used to supply breathing air to a diver must have— (a) A volume tank that is— (1) Built and stamped in...

Apollo 9 crewman crawls onto life raft after splashdown in Atlantic

NASA Technical Reports Server (NTRS)

1969-01-01

Aerial view of an Apollo 9 crewman egressing the command module onto a life raft after splashdown in the Atlantic recovery area and a successful ten-day, earth-orbital space mission. Navy divers have already attached a flotation collar to the command module and are assisting with recovery operations.

Divers revisited: The ventilatory response to carbon dioxide in experienced scuba divers.

PubMed

Earing, Christopher Matthew Norton; McKeon, Damian John; Kubis, Hans-Peter

2014-05-01

To investigate the ventilatory response to CO2 in hyperoxia, hypoxia, and during exercise amongst experienced scuba divers and matched controls. Two studies were performed. The first investigated the CO2 sensitivity in rest and exercise using CO2 rebreathing in hyperoxia at a workload typical for diving with divers (n = 11) and controls (n = 11). The second study examined the respiratory drive of divers (n = 10) and controls (n = 10) whilst breathing four different gas mixtures balanced with N2 (ambient air; 25% O2/6% CO2; 13% O2; 13% O2/6% CO2) to assess the combined response to hypercapnia and moderate hypoxia. Exercise at a load typical for diving was found to have no effect on the ventilatory sensitivity to CO2 in divers (rest: 1.49 ± 0.33; exercise: 1.22 ± 0.55 [l/min × mmHg(-1)]) and controls (rest: 2.08 ± 0.71; exercise: 2.05 ± 0.98 [l/min × mmHg(-1)]) while differences in sensitivity remained between the groups. Inhalation of the four gas mixtures revealed the tested oxygen pressures caused no significant alteration in the ventilatory sensitivity to CO2 in divers and controls. Experienced divers possess a lower ventilatory response to CO2 which was not affected by exercise or the tested oxygen pressures suggesting a dominant adaptation of central CO2 sensitivity. Copyright © 2014 Elsevier Ltd. All rights reserved.

Oceanography for Divers: Hazardous Marine Life. Diver Education Series.

ERIC Educational Resources Information Center

Somers, Lee H.

Most people find that the life of the marine environment is beautiful and fascinating. Of the thousands of marine animals and plants, relatively few constitute a real hazard to the diver. Although some species are dangerous and may, in some instances, inflict serious wounds, with a few exceptions marine animals are not aggressive. Most…

Funding conservation through use and potentials for price discrimination among scuba divers at Sipadan, Malaysia.

PubMed

Emang, Diana; Lundhede, Thomas Hedemark; Thorsen, Bo Jellesmark

2016-11-01

The protected coral reefs off the coast of Malaysia receive numerous tourists, while also being as fishing grounds. These joint environmental pressures raise the need for additional costly conservation measures. It is natural to consider the potential for expanding the 'user pays' principle, already implemented in the form of various user fees. This study explores the potential for price discrimination among scuba divers at Sipadan in Malaysia. The study applies a choice experiment to estimate scuba divers willingness to pay higher user fees for avoiding decreases of or getting improvements in environmental and recreational aspects of the diving experience. We investigate how sensitivity to fee size and hence willingness to pay vary with suitable selected characteristics of divers. We find potentials for a third degree price discrimination strategy exploiting higher willingness to pay among foreign divers (45%), male divers (16%) and people who has visited Sipadan several times (25%). Thus, revised pricing structures could significantly increase funds for the preservation of Sipadan. Copyright © 2016 Elsevier Ltd. All rights reserved.

KSC-02pd1300

NASA Image and Video Library

2002-09-11

KENNEDY SPACE CENTER, FLA. -- United Space Alliance workers on board the Freedom Star, one of the Shuttle Rocket Booster retrieval ships, check the controls on the recompression chamber at right. The ship and its dive team, including a diver medical technician, Andy Fish, were instrumental in rescuing a lobster diver in distress off Cape Canaveral Sept. 11. The ship was on a certification exercise and near the location of a lobster diving boat that radioed the U.S. Coast Guard for help when one of the divers experienced difficulty breathing on his return to the surface. Hearing the call for help, the captain of the Freedom Star offered to help. Fish stayed with the diver in the recompression chamber aboard the Freedom Star until the ship reached Port Canaveral where a KSC Occupational Health doctor waited. The diver was stabilized and taken to Florida Hospital.

An Adaptive Approach for Precise Underwater Vehicle Control in Combined Robot-Diver Operations

DTIC Science & Technology

2015-03-01

addressing rigid body and added mass, Coriolis effects , damping and restoring forces. 3. System Modeling for THAUS-like Platforms Yuh [3] presents...term, ( )C  is the rigid body and added mass Coriolis effects , ( )D  is the damping term, and )(g  is the reactionary force term. The second...operations potentially increase the efficiency, effectiveness and safety of the tasks they perfonn. The utilization of an autonomous unde1water vehicle

Recreational SCUBA divers' willingness to pay for marine biodiversity in Barbados.

PubMed

Schuhmann, Peter W; Casey, James F; Horrocks, Julia A; Oxenford, Hazel A

2013-05-30

The use of natural resources and the services they provide often do not have an explicit price and are therefore undervalued in decision-making, leading to environmental degradation. To 'monetize' the benefits from these services requires the use of non-market valuation techniques. Using a stated preference survey of recreational divers in Barbados conducted between 2007 and 2009, the economic value of marine biodiversity to recreational SCUBA divers in Barbados was estimated. In addition to a variety of demographic variables, divers were asked about their level of experience, expenditures related to travel and diving, and encounters with fish and sea turtles. Divers then completed a choice experiment, selecting between alternative dives with varying characteristics including price, crowding, fish diversity, encounters with sea turtles, and coral cover. Results indicate that divers in Barbados have a clear appreciation of reef quality variables. Willingness to pay for good coral cover, fish diversity and presence of sea turtles is significantly higher than prices paid for dives. In general, divers valued reef attributes similarly, although their appreciation of low density of divers at a site and high coral cover varied with prior diving experience. The results of this study demonstrate the economic value generated in Barbados by the recreational SCUBA diving industry and highlight the potential for substantial additional economic contributions with improvements to the quality of a variety of reef attributes. These results could inform management decisions regarding reef use and sea turtle conservation, and could aid in the development of informed 'win-win' policies aimed at maximizing returns from diving while reducing negative impacts often associated with tourism activities. Copyright © 2013 Elsevier Ltd. All rights reserved.

Violations of safe diving practices among 122 diver fatalities.

PubMed

Shreeves, Karl; Buzzacott, Peter; Hornsby, Al; Caney, Mark

2018-01-01

Diving is a popular recreation with an excellent safety record, with an estimated 1.8 deaths per 1 million dives. This study investigated the relationship between intentional deviation from accepted diving practices (violations) and diver fatalities. The authors examined 119 incidents/122 diver fatalities that did not involve diver training in North America and the Caribbean, and identified the presence of violations of accepted diving safety practices, as well as if the death was associated with an acute medical event such as heart attack. Of the 122 fatalities, 57% (n = 70) were associated with a medical event and 43% (n = 52) were non-medical. Violations were found in 45% of fatalities (n = 55) overall. Violations were recorded for 23% of the 70 medical and 75% of the 52 non-medical fatalities. Divers who died from something other than a medical cause were 7 times as likely to have one or more violations associated with the fatality (OR 7.3, 95% CI 2.3-23.2). The odds of dying from something other than a medical condition increased approximately 60% for each additional 10 metres of depth. The odds of a death being associated with a medical condition increased approximately 9% per year of age, or 2.4 times for every 10 years older a diver was. Medical events are associated with over half of the non-training related diver fatalities in North America and the Caribbean, with the odds of death being associated with a medical condition doubling each decade of additional age. These data support recommendations that divers stay physically fit and have regular medical checkups, particularly as they get older. They also strongly support the safety benefit of adhering to established safe diving practices.

Learning from a dive show in an aquarium setting

NASA Astrophysics Data System (ADS)

Walsh, Lori M.

A study was conducted at an aquarium next to a theme park to understand information recalled from two versions of shows viewed at the largest display. The goal of this research was to determine if learning was enhanced by having a diver in water as the treatment group. This project focused on the knowledge recalled about shark and ray feeding adaptations, the information recalled about the mentioned conservation message about sustainable seafood and the potential of the two shows to make memorable experiences. During the project, 30 adult participants from each group were given a survey with five open-ended questions. Results suggest that the diver might distract from biological content information, or that the diver is such a novel element that it interferes with recall. While guests seemed to recall information about rays and sharks, the amount of information was not substantial. It appears that the diver does not affect content messaging but does impact whether guests attend to Seafood Watch messaging. The diver may have been so novel that the treatment group could not attend to the conservation message that was delivered, regardless of topic, or the control group recalled the message because the guests were not distracted by the diver or feeding. The absence of a diver seems to allow the guests to better attend to what is happening outside of the tank. While adding a diver increases photo opportunities and may bring guests to a show, the results seem to indicate that it does not significantly increase recall. The results of this study show that guests in a theme park setting can recall information from an educational program. Guests may not enter this hybrid aquarium with the intention of learning, but recall, one of the components in learning, does occur.

Gut fermentation seems to promote decompression sickness in humans.

PubMed

de Maistre, Sébastien; Vallee, Nicolas; Gempp, Emmanuel; Louge, Pierre; Duchamp, Claude; Blatteau, Jean-Eric

2016-10-01

Massive bubble formation after diving can lead to decompression sickness (DCS) that can result in neurological disorders. In experimental dives using hydrogen as the diluent gas, decreasing the body's H 2 burden by inoculating hydrogen-metabolizing microbes into the gut reduces the risk of DCS. In contrast, we have shown that gut bacterial fermentation in rats on a standard diet promotes DCS through endogenous hydrogen production. Therefore, we set out to test these experimental results in humans. Thirty-nine divers admitted into our hyperbaric center with neurological DCS (Affected Divers) were compared with 39 healthy divers (Unaffected Divers). Their last meal time and composition were recorded. Gut fermentation rate was estimated by measuring breath hydrogen 1-4 h after the dive. Breath hydrogen concentrations were significantly higher in Affected Divers (15 ppm [6-23] vs. 7 ppm [3-12]; P = 0.0078). With the use of a threshold value of 16.5 ppm, specificity was 87% [95% confidence interval (CI) 73-95] for association with neurological DCS onset. We observed a strong association between hydrogen values above this threshold and an accident occurrence (odds ratio = 5.3, 95% CI 1.8-15.7, P = 0.0025). However, high fermentation potential foodstuffs consumption was not different between Affected and Unaffected Divers. Gut fermentation rate at dive time seemed to be higher in Affected Divers. Hydrogen generated by fermentation diffuses throughout the body and could increase DCS risk. Prevention could be helped by excluding divers who are showing a high fermentation rate, by eliminating gas produced in gut, or even by modifying intestinal microbiota to reduce fermentation rate during a dive. Copyright © 2016 the American Physiological Society.

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

The first controlled-temperature ice plug in the bend of an offshore gas trunkline has been carried out for Phillips Petroleum Co. Norway on its Norpipe A.S. platform in the German sector of the North Sea. The procedure was part of a subsea valve repair operation. The ice plug was successfully formed offshore and tested to a differential pressure of 1,450 psi. Repair of two valves required only 5 days during which time gas production was operating at close to 50--60% via the platform bypass, says the service company. The paper discusses the procedure.

KSC-02pd1299

NASA Image and Video Library

2002-09-11

KENNEDY SPACE CENTER, FLA. - On board the Freedom Star, one of the Shuttle Rocket Booster retrieval ships, workers with United Space Alliance help finalize the rescue of a lobster diver in distress after their return to port Sept. 11. The ship was on a certification exercise and near the location of a lobster diving boat that radioed the U.S. Coast Guard for help when one of the divers experienced difficulty breathing on his return to the surface. Hearing the call for help, the captain of the Freedom Star offered to help. On board the ship was a dive team, including a diver medical technician, Andy Fish, who are trained to assist in case of a dive accident during a retrieval mission. Fish stayed with the diver in the recompression chamber aboard the Freedom Star until the ship reached Port Canaveral where a KSC Occupational Health doctor waited. The diver was stabilized and taken to Florida Hospital.

Thermal and metabolic responses of military divers during a 6-hour static dive in cold water.

PubMed

Riera, Florence; Horr, Reed; Xu, Xiaojiang; Melin, Bruno; Regnard, Jacques; Bourdon, Lionel

2014-05-01

Human thermal responses during prolonged whole-body immersion in cold water are of interest for the military, especially French SEALS. This study aims at describing the thermo-physiological responses. There were 10 male military divers who were randomly assigned to a full immersion in neutral (34 degrees C), moderately cold (18 degrees C), and cold (10 degrees C) water wearing their operational protective devices (5.5 mm wetsuit with 3.0 mm thick underwear) for 6 h in a static position. Rectal temperature (T(re)) and 14 skin temperatures (T(sk)), blood analysis (stress biomarkers, metabolic substrates), and oxygen consumption (Vo2) were collected. At 34 degrees C, there were no significant modifications of the thermo-physiological responses over time. The most interesting result was that rates of rectal temperature decrease (0.15 +/- 0.02 degrees C x min(-1)) were the same between the two cold stress experimental conditions (at 18 degrees C and 10 degrees C). At the final experiment, rectal temperature was not significantly different between the two cold stress experimental conditions. Mean T(sk) decreased significantly during the first 3 h of immersion and then stabilized at a lower level at 10 degrees C (25.6 +/- 0.8 degrees C) than at 18 degrees C (29.3 +/- 0.9 degrees C). Other results demonstrate that the well-trained subjects developed effective physiological reactions. However, these reactions are consistently too low to counterbalance the heat losses induced by cold temperature conditions and long-duration immersion. This study shows that providing divers with thermal protection is efficient for a long-duration immersion from a medical point of view, but not from an operational one when skin extremities were taken into account.

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

PubMed

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 sufficiently favourable circumstances (such as: a large quantity of VGE, size of the PFO, straining or provocation manoeuvres inducing increased right atrial pressure, delayed tissue desaturation so that seeding arterial gas emboli (AGE) grow instead of shrink, and there may be other, as yet unknown factors). There is no doubt that closing a PFO, either surgically or using a catheter-delivered device, can reduce the number of VGE becoming AGE. There is also no doubt that the procedure itself carries some health risks which are, at 1% or higher risk of serious complications, an order of magnitude greater than the risk for decompression illness (DCI) in recreational diving. Scientists seek the 'truth', but the truth about how much of a risk PFO represents for divers is not likely to be discovered nor universally accepted. First of all, the exact prevalence of PFO in divers is not known. As it has been pointed out in the recent literature, a contrast echocardiography (be it transthoracic or transoesophageal) or Doppler examination is only reliable if performed according to a strict protocol, taking into account the very many pitfalls yielding false negative results. The optimal procedure for injection of contrast medium was described several years ago, but has not received enough attention. Indeed, it is our and others' experience that many divers presenting with PFO-related DCI symptoms initially are declared "PFO-negative" by eminent, experienced cardiologists! Failing a prospective study, the risks of diving with a right-to left vascular shunt can only be expressed as an 'odds ratio', which is a less accurate measure than is 'relative risk'. The DAN Europe Carotid Doppler Study, started in 2001, is nearing completion and will provide more insight into the actual risks of DCI for recreational divers. The degree of DCI risk reduction from closing a PFO is thus not only dependent on successful closure but also (mostly?) on how the diver manages his/her dive and decompression in order to reduce the incidence of VGE. It has been convincingly shown that conservative dive profiles reduce DCI incidence even in divers with large PFOs, just as PFO closure does not protect completely from DCI if the dive profiles are aggressive. Prospective studies should not only focus on the reduction of DCI incidence after closure, but should take into account the costs and side effects of the procedure, as has been done in the cardiology and neurology studies. Imagine lung transplants becoming a routine operation, costly but with a high success rate; imagine also a longterm smoker suffering from a mild form of obstructive lung disease and exercise-limiting dyspnoea. Which of two options would you recommend: having a lung transplant and continue smoking as before, or quit smoking and observe a progressive improvement of pulmonary and cardiac pathology? As opposed to patients with thrombotic disease and migraine, divers can choose to reduce DCI risk. In fact, all it takes is acceptance that some types of diving carry too high a health risk - whether it is because of a PFO or another 'natural' factor. It would be unethical to promote PFO closure in divers solely on the basis of its efficacy of shunt reduction. Unfortunately, at least one device manufacturer has already done so in the past, citing various publications to specifically target recreational divers. Some technical diving organizations even have recommended preventive PFO closure in order to undertaking high-risk dive training. As scientists, we must not allow ourselves to be drawn into intuitive diver fears and beliefs. Nor should we let ourselves be blinded by the ease and seemingly low risk of the procedure. With proper and objective information provided by their diving medicine specialist, divers could make an informed decision, rather than focus on the simplistic idea that they need 'to get it fixed' in order to continue diving. A significant relationship between PFO and cerebral damage, in the absence of high-risk diving or DCI, has yet to be confirmed. Studying PFO-related DCI provides us with unique opportunities to learn more about the effect of gas bubbles in various tissues, including the central vascular bed and neurological tissue. It may also serve to educate divers that safe diving is something that needs to be learned, not something that can be implanted.

Free jet feasibility study of a thermal acoustic shield concept for AST/VCE application-dual flow. Comprehensive data report. Volume 1: Test nozzles and acoustic data

NASA Technical Reports Server (NTRS)

Janardan, B. A.; Brausch, J. F.; Price, A. O.

1984-01-01

Acoustic and diagnostic data that were obtained to determine the influence of selected geometric and aerodynamic flow variables of coannular nozzles with thermal acoustic shields are summarized in this comprehensive data report. A total of 136 static and simulated flight acoustic test points were conducted with 9 scale-model nozzles The tested nozzles included baseline (unshielded), 180 deg shielded, and 360 deg shielded dual flow coannular plug configurations. The baseline configurations include a high radius ratio unsuppressed coannular plug nozzle and a coanuular plug nozzle and a coannular plug nozzle with a 20-chute outer stream suppressor. The tests were conducted at nozzle temperatures and pressure typical of operating conditions of variable cycle engine.

AVTA Federal Fleet PEV Readiness Data Logging and Characterization Study for the National Park Service: Sleeping Bear Dunes National Lakeshore

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schey, Stephen; Francfort, Jim

This report focuses on the Sleeping Bear Dunes National Lakeshore (SLBE) fleet to identify daily operational characteristics of select vehicles and report findings on vehicle and mission characterizations to support the successful introduction of plug-in electric vehicles (PEVs) into the agencies’ fleets. Individual observations of these selected vehicles provide the basis for recommendations related to electric vehicle adoption and whether a battery electric vehicle (BEV) or plug-in hybrid electric vehicle (PHEV) (collectively plug-in electric vehicles, or PEVs) can fulfill the mission requirements.

Demonstration of Remotely Operated Vehicles to Aid Underwater Inspection of Corps of Engineers Navigation Structures. Winfield Locks and Dam 13-17 August 2007

DTIC Science & Technology

2008-09-01

2 Deep Ocean Engineering Triggerfish ...Figures Figure 1. Deep Ocean Engineering Triggerfish ROV carried by two divers (top)................................... 4 Figure 2. SeaBotix...the physical parameters and approximate costs of the systems as tested. Deep Ocean Engineering Triggerfish Figure 1 shows the Deep Ocean

Apollo 9 crewman in rescue net being hoisted up to helicopter

NASA Image and Video Library

1969-03-13

Aerial view of an Apollo 9 crewman in a new rescue net (a Billy Pugh net) being hoisted aboard a Navy helicopter after splashdown in the Atlantic recovery area and a successful ten-day, earth-orbital space mission. Navy divers have already attached a flotation collar to the command module and are assisting with recovery operations.

SEALIFT

DTIC Science & Technology

2012-03-01

Dolores Chouest served primarily as a platform for U.S. and Canadian divers to conduct diving operations. MSC Maritime Prepositioning Force ship...Kanawha also performed an underway replenishment following a short-fused request by Canadian navy frigate HMCS Vancouver, allowing Vancouver to bypass...planning careers within the maritime industry . Fourteen MSCPAC and Ship Sup- port Unit San Diego employees served as MSC representatives at the

Differences in SCUBA diver motivations based on level of development

Treesearch

Sharon L. Todd; Alan R. Graefe; Walter Mann

2002-01-01

This study examined SCUBA divers' level of development in relationship to their motivations to dive. During the fall of 1999,869 divers ranging from beginners to post-experts were surveyed (37% response rate). Respondents ranked 24 motives on a 5-point importance scale. When the data were reduced using factor analysis to tease out major themes, six factors (...

Are recreational SCUBA divers with asthma at increased risk?

PubMed

Ustrup, Amalie S; Ulrik, Charlotte S

2017-10-01

Asthma has traditionally been regarded as a contraindication to self-contained underwater breathing apparatus (SCUBA) diving, although large numbers of patients with asthma dive. The aim of the review is to provide an update on current knowledge on potential disease-related hazards in SCUBA divers with asthma. Systematic literature review based on the Preferred Reporting Items for Systematic reviews and Meta-Analyses (PRISMA) guidelines. Seven studies met the criteria for inclusion in the review (comprising a total of 560 subjects). Five studies reported an increased risk for developing diving-related injuries in divers with asthma, based on case reports (n = 1), case history combined with objective assessment (n = 1), and dives and/or simulated dives (n = 3). The remaining studies (n = 2) were based on self-reported diving habits in divers suffering from asthma, obtained from anonymous questionnaires in diving magazines, reported no diving-related injuries among respondents. Due to limited evidence it is difficult to draw valid conclusions, but there are indications that recreational divers with asthma may be at increased risk for diving-related injuries compared to non-asthmatic divers. However, it is of at most importance to obtain further evidence from large-scale, well-designed studies.

The neuropsychology of repeated 1- and 3-meter springboard diving among college athletes.

PubMed

Zillmer, Eric A

2003-01-01

This study examined the neuropsychological effects of repeated springboard diving. It was hypothesized that the impact velocity, which can range from 20 to 30 mph, and accompanying deceleration in the water may lead to concussions and affect the diver's cognitive function. Six varsity National Collegiate Athletic Association Division 1 springboard divers participated in the study. Each diver performed a total of 50 practice dives from either the 1- or 3-m springboard. After each set of 10 dives, the participants were immediately evaluated at poolside using the Symbol Digit Modalities Test, the Stroop Color Word Test, and the Trail Making Test B. Baseline testing revealed, consistent with their athletic specialty, clear neurocognitive strengths among the divers on tests sensitive to proprioception, motor speed, and visual-spatial organization. Results from the serial assessments indicated no detectable neuropsychological deficits among competitive divers compared to baseline testing. Skilled diving at the collegiate level appears to be a safe sport and water appears to present the perfect medium for gradual deceleration. More studies, however, are warranted for 5-, 7.5-, and 10-m platform diving since the impact velocity of the diver from these heights is higher.

Forensic Fluid Dynamics and the Indian Spring (1991) cave collapse problem

NASA Astrophysics Data System (ADS)

Nof, D.

2013-05-01

The collapse of the Indian spring cave (Florida) in 1991 was unique because it occurred while cave divers were in the cave. For the most part, the submerged cave is large enough to accommodate a passing truck so the cave divers were not in touch with its walls and it is hard to imagine why would it naturally collapse just when the divers were in it. Recently, Nof and Paldor (2010) resolved this apparent paradox by suggesting that resonance in the air pockets in the cavern, created by breathing (open circuit) divers, may have contributed to the collapse. In this scenario, divers present in the cavern during the dive may have (unknowingly) caused the collapse through the pressurized air/gas that they release with each breath. When the breathing period of the diver(s) matches the natural oscillations period of the "cave oscillator", the ensuing resonance causes the air pressure in the pockets to increase uncontrollably. Here, we place the above theory on a more solid ground. To do so, we first extended the resonance theory from our original two-pockets, symmetrical U-tube model (with two identical branches that were not specifically identified within the cave system) to a one (identified) pocket in the cavern and a very broad basin (identified, of course) that serves as the other branch of the U-tube. Our methodology is to apply familiar fluid dynamics principles to the situation that occurred in the cave. We did so, step-by-step, on the basis of our interviews with four out of the five surviving cave-divers. Namely, we dissected their testimonies to arrive at a physically plausible scenario determined on basis of a fluid dynamics application to the natural flow in the cave and the flow induced by the compressed air released by the divers as well as the collapsed mud. We found that the oscillation period was larger than what we earlier calculated (still relevant to the case, nevertheless), and that, in contrast to what most cave divers believe, there was a temporary flow blocking during the collapse but no total flow reversal within the cave. Observed swirling in the basin during the collapse is attributed to a dipole flow corresponding to an inflow and outflow from the cave.

NaK Plugging Meter Design for the Feasibility Test Loops

NASA Technical Reports Server (NTRS)

Pearson, J. Boise; Godfroy, Thomas J.; Reid, Robert S.; Polzin, Kurt A.

2008-01-01

The design and predicted performance of a plugging meter for use in the measurement of NaK impurity levels are presented. The plugging meter is incorporated into a Feasibility Test Loop (FTL), which is a small pumped-NaK loop designed to enable the rapid, small-scale evaluation of techniques such as in situ purification methods and to permit the measurement of bulk material transport effects (not mechanisms) under flow conditions that are representative of a fission surface power reactor. The FTL operates at temperatures similar to those found in a reactor, with a maximum hot side temperature of 900 K and a corresponding cold side temperature of 860 K. In the plugging meter a low flow rate bypass loop is cooled until various impurities (primarily oxides) precipitate out of solution. The temperatures at which these impurities precipitate are indicative of the level of impurities in the NaK. The precipitates incrementally plug a small orifice in the bypass loop, which is detected by monitoring changes in the liquid metal flow rate.

Patent foramen ovale influences the presentation of decompression illness in SCUBA divers.

PubMed

Liou, Kevin; Wolfers, Darren; Turner, Robert; Bennett, Michael; Allan, Roger; Jepson, Nigel; Cranney, Greg

2015-01-01

Few have examined the influence of patent foramen ovale (PFO) on the phenotype of decompression illness (DCI) in affected divers. A retrospective review of our database was performed for 75 SCUBA divers over a 10-year period. Overall 4,945 bubble studies were performed at our institution during the study period. Divers with DCI were more likely to have positive bubble studies than other indications (p<0.001). Major DCI was observed significantly more commonly in divers with PFO than those without (18/1,000 v.s. 3/1,000, p=0.02). Divers affected by DCI were also more likely to require a longer course of hyperbaric oxygen therapy (HBOT) if PFO was present (p=0.038). If the patient experienced one or more major DCI symptoms, the odds ratio of PFO being present on a transoesophageal echocardiogram was 3.2 (p=0.02) compared to those who reported no major DCI symptoms. PFO is highly prevalent in selected SCUBA divers with DCI, and is associated with a more severe DCI phenotype and longer duration of HBOT. Patients with unexpected DCI with one or more major DCI symptoms should be offered PFO screening if they choose to continue diving, as it may have considerable prognostic and therapeutic implications. Copyright © 2014 Australian and New Zealand Society of Cardiac and Thoracic Surgeons (ANZSCTS) and the Cardiac Society of Australia and New Zealand (CSANZ). Published by Elsevier B.V. All rights reserved.

Comparison of the size of persistent foramen ovale and atrial septal defects in divers with shunt-related decompression illness and in the general population.

PubMed

Wilmshurst, Peter T; Morrison, W Lindsay; Walsh, Kevin P

2015-06-01

Decompression illness (DCI) is associated with a right-to-left shunt, such as persistent foramen ovale (PFO), atrial septal defect (ASD) and pulmonary arteriovenous malformations. About one-quarter of the population have a PFO, but considerably less than one-quarter of divers suffer DCI. Our aim was to determine whether shunt-related DCI occurs mainly or entirely in divers with the largest diameter atrial defects. Case control comparison of diameters of atrial defects (PFO and ASD) in 200 consecutive divers who had transcatheter closure of an atrial defect following shunt-related DCI and in an historic group of 263 individuals in whom PFO diameter was measured at post-mortem examination. In the divers who had experienced DCI, the median atrial defect diameter was 10 mm and the mean (standard deviation) was 9.9 (3.6) mm. Among those in the general population who had a PFO, the median diameter was 5 mm and mean was 4.9 (2.6) mm. The difference between the two groups was highly significant (P < 0.0001). Of divers with shunt-related DCI, 101 (50.5%) had an atrial defect 10 mm diameter or larger, but only 1.3% of the general population studied had a PFO that was 10 mm diameter of larger. The risk of a diver suffering DCI is related to the size of the atrial defect rather than just the presence of a defect.

Experimental investigation of shock-cell noise reduction for dual-stream nozzles in simulated flight

NASA Technical Reports Server (NTRS)

Janardan, B. A.; Yamamoto, K.; Majjigi, R. K.; Brausch, J. F.

1984-01-01

Six scale-model nozzles were tested in an anechoic facility to evauate the effectiveness of convergent-divergent (C-D) terminations in reducing shock-cell noise of unsuppressed and mechanically suppressed coannular plug nozzles. One hundred fifty-three acoustic test points with inverted velocity profiles were conducted under static and simulated flight conditions. Diagnostic flow visualization with a shadowgraph and velocity measurements with a laser velocimeter were performed on selected plumes. Shock-cells were identified on the plug and downstream of the plug of the unsuppressed convergent coannular nozzle with truncated plug. Broadband peak frequencies predicted with the two shock-cell structures were correlated with the observed spectra using the measured shock-cell spacings. Relative to a convergent circular nozzle, the perceived noise level (PNL) data at an observer angle of 60 deg relative to inlet, indicated a reduction of (1) 6.5 dB and 9.2 dB with unsuppressed C-D coannular nozzle with truncated plug and (2) 7.7 dB and 8.3 dB with suppressed C-D coannular nozzle under static and simulated flight conditions, espectively. The unsuppressed C-D coannular nozzle with truncated plug, operating at the C-D design condition, had shock-cells downstream of the plug with no shock-cells on the plug. The downstream shock-cells were eliminated by replacing the truncated plug with a smooth extension to obtain an additional 2.4 dB and 3 dB front quadrant PNL reduction, under static and simulated flight conditions, respectively. Other results are discussed.

Supervisory Control of Remote Manipulation with Compensation for Moving Target.

DTIC Science & Technology

1980-07-21

Continue on reveree aide if neceeary and Identify by block number) ’The aim of this project is to evaluate automatic compensation for moving tar- gets ...slave control. Operating manipulators in this way is a tiring job and the operator gets exhausted after j a short time of work. The use of the computer...THE MANIPULATION OF MOVING OBJECTS Undersea tasks done by human divers are getting more and more costly and hazardous as they have to be done at

A Modified Prophylactic Regimen for the Prevention of Otitis Externa in Saturation Divers

DTIC Science & Technology

2013-10-01

Prophylactic Regimen for the Prevention of Otitis Externa in Saturation Divers Authors: DISTRIBUTION STATEMENT A. Paul C. Algra, LT, MC...May 2012 – May 2013 4. TITLE AND SUBTITLE A Modified Prophylactic Regimen for the Prevention of Otitis Externa in Saturation Divers...SUPPLEMENTARY NOTES 14. ABSTRACT To prevent acute otitis externa (AOE) in the saturation setting and to decrease the side effects

The Relationship between Diver Experience Levels and Perceptions of Attractiveness of Artificial Reefs - Examination of a Potential Management Tool

PubMed Central

Kirkbride-Smith, Anne E.; Wheeler, Philip M.; Johnson, Magnus L.

2013-01-01

Artificial reefs are increasingly used worldwide as a method for managing recreational diving since they have the potential to satisfy both conservation goals and economic interests. In order to help maximize their utility, further information is needed to drive the design of stimulating resources for scuba divers. We used a questionnaire survey to explore divers’ perceptions of artificial reefs in Barbados. In addition, we examined reef resource substitution behaviour among scuba divers. Divers expressed a clear preference for large shipwrecks or sunken vessels that provided a themed diving experience. Motives for diving on artificial reefs were varied, but were dominated by the chance of viewing concentrated marine life, increased photographic opportunities, and the guarantee of a ‘good dive’. Satisfaction with artificial reef diving was high amongst novices and declined with increasing experience. Experienced divers had an overwhelming preference for natural reefs. As a management strategy, our results emphasize the capacity of well designed artificial reefs to contribute towards the management of coral reef diving sites and highlight a number of important areas for future research. Suggested work should validate the present findings in different marine tourism settings and ascertain support of artificial reefs in relationship to level of diver specialization. PMID:23894372

Provisional report on diving-related fatalities in Australian waters in 2011.

PubMed

Lippmann, John; Lawrence, Christopher; Fock, Andrew; Jamieson, Scott; Harris, Richard

2016-12-01

An individual case review of diving-related deaths reported as occurring in Australia in 2011 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, where available, details from the post-mortem examination are provided. A chain of events analysis was conducted for each case. In total, there were 30 reported fatalities (10 more than in 2010). These included 15 snorkel/breath-hold divers, 14 scuba divers and one diver using surface-supplied breathing apparatus. Twenty-four victims were males. The mean age of snorkelling victims was 49.6 (range 23-75) years and compressed gas divers 42.2 (range 23-55) years. Cardiac-related issues were thought to have been the disabling injury in the deaths of at least seven snorkel divers and five scuba divers. Immersion pulmonary oedema was implicated in at least one death; and three fatalities resulted from attacks by marine animals. Two novices died while under instruction/supervision after separation from their instructor in poor visibility. Pre-existing medical conditions, separation and inadequate supervision and seafood collection in areas frequented by marine predators were once again features in several deaths in this series.

Asystole and increased serum myoglobin levels associated with 'packing blackout' in a competitive breath-hold diver.

PubMed

Andersson, Johan P A; Linér, Mats H; Jönsson, Henrik

2009-11-01

Many competitive breath-hold divers use 'glossopharyngeal insufflation', also called 'lung packing', to overfill their lungs above normal total lung capacity. This increases intrathoracic pressure, decreases venous return, compromises cardiac pumping, and reduces arterial blood pressure, possibly resulting in a syncope breath-hold divers call 'packing blackout'. We report a case with a breath-hold diver who inadvertently experienced a packing blackout. During the incident, an electrocardiogram (ECG) and blood pressure were recorded, and blood samples for determinations of biomarkers of cardiac muscle perturbation (creatine kinase-MB isoenzyme (CK-MB), cardiac troponin-T (TnT), and myoglobin) were collected. The ECG revealed short periods of asystole during the period of 'packing blackout', simultaneous with pronounced reductions in systolic, diastolic, and pulse pressures. Serum myoglobin concentration was elevated 40 and 150 min after the incident, whereas there were no changes in CK-MB or TnT. The ultimate cause of syncope in this diver probably was a decrease in cerebral perfusion following glossopharyngeal insufflation. The asystolic periods recorded in this diver could possibly indicate that susceptible individuals may be put at risk of a serious cardiac incident if the lungs are excessively overinflated by glossopharyngeal insufflation. This concern is further substantiated by the observed increase in serum myoglobin concentration after the event.

Modelling of plug and play interface for energy router based on IEC61850

NASA Astrophysics Data System (ADS)

Shi, Y. F.; Yang, F.; Gan, L.; He, H. L.

2017-11-01

Under the background of the “Internet Plus”, as the energy internet infrastructure equipment, energy router will be widely developed. The IEC61850 standard is the only universal standard in the field of power system automation which realizes the standardization of engineering operation of intelligent substation. To eliminate the lack of International unified standard for communication of energy router, this paper proposes to apply IEC61850 to plug and play interface and establishes the plug and play interface information model and information transfer services. This paper provides a research approach for the establishment of energy router communication standards, and promotes the development of energy router.

Comparison of an Inductance In-Line Oil Debris Sensor and Magnetic Plug Oil Debris Sensor

NASA Technical Reports Server (NTRS)

Dempsey, Paula J.; Tuck, Roger; Showalter, Stephen

2012-01-01

The objective of this research was to compare the performance of an inductance in-line oil debris sensor and magnetic plug oil debris sensor when detecting transmission component health in the same system under the same operating conditions. Both sensors were installed in series in the NASA Glenn Spiral Bevel Gear Fatigue Rig during tests performed on 5 gear sets (pinion/gear) when different levels of damage occurred on the gear teeth. Results of this analysis found both the inductance in-line oil debris sensor and magnetic plug oil debris sensor have benefits and limitations when detecting gearbox component damage.

Oxygen monitor for semi-closed rebreathers: design and use for estimating metabolic oxygen consumption

NASA Astrophysics Data System (ADS)

Clarke, John R.; Southerland, David

1999-07-01

Semi-closed circuit underwater breathing apparatus (UBA) provide a constant flow of mixed gas containing oxygen and nitrogen or helium to a diver. However, as a diver's work rate and metabolic oxygen consumption varies, the oxygen percentages within the UBA can change dramatically. Hence, even a resting diver can become hypoxic and become at risk for oxygen induced seizures. Conversely, a hard working diver can become hypoxic and lose consciousness. Unfortunately, current semi-closed UBA do not contain oxygen monitors. We describe a simple oxygen monitoring system designed and prototyped at the Navy Experimental Diving Unit. The main monitor components include a PIC microcontroller, analog-to-digital converter, bicolor LED, and oxygen sensor. The LED, affixed to the diver's mask is steady green if the oxygen partial pressure is within pre- defined acceptable limits. A more advanced monitor with a depth senor and additional computational circuitry could be used to estimate metabolic oxygen consumption. The computational algorithm uses the oxygen partial pressure and the diver's depth to compute O2 using the steady state solution of the differential equation describing oxygen concentrations within the UBA. Consequently, dive transients induce errors in the O2 estimation. To evalute these errors, we used a computer simulation of semi-closed circuit UBA dives to generate transient rich data as input to the estimation algorithm. A step change in simulated O2 elicits a monoexponential change in the estimated O2 with a time constant of 5 to 10 minutes. Methods for predicting error and providing a probable error indication to the diver are presented.

Nutritional recommendations for divers.

PubMed

Benardot, Dan; Zimmermann, Wes; Cox, Gregory R; Marks, Saul

2014-08-01

Competitive diving involves grace, power, balance, and flexibility, which all require satisfying daily energy and nutrient needs. Divers are short, well-muscled, and lean, giving them a distinct biomechanical advantage. Although little diving-specific nutrition research on performance and health outcomes exists, there is concern that divers are excessively focused on body weight and composition, which may result in reduced dietary intake to achieve desired physique goals. This will result in low energy availability, which may have a negative impact on their power-to-weight ratio and health risks. Evidence is increasing that restrictive dietary practices leading to low energy availability also result in micronutrient deficiencies, premature fatigue, frequent injuries, and poor athletic performance. On the basis of daily training demands, estimated energy requirements for male and female divers are 3,500 kcal and 2,650 kcal, respectively. Divers should consume a diet that provides 3-8 g/kg/day of carbohydrate, with the higher values accommodating growth and development. Total daily protein intake (1.2-1.7 g/kg) should be spread evenly throughout the day in 20 to 30 g amounts and timed appropriately after training sessions. Divers should consume nutrient-dense foods and fluids and, with medical supervision, certain dietary supplements (i.e., calcium and iron) may be advisable. Although sweat loss during indoor training is relatively low, divers should follow appropriate fluid-intake strategies to accommodate anticipated sweat losses in hot and humid outdoor settings. A multidisciplinary sports medicine team should be integral to the daily training environment, and suitable foods and fluids should be made available during prolonged practices and competitions.

16. NBS TOPSIDE CONTROL ROOM, THE NBS HYPERBARIC CHAMBER IS ...

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

16. NBS TOPSIDE CONTROL ROOM, THE NBS HYPERBARIC CHAMBER IS VERY CLOSE TO THE WATER'S EDGE AND HERE FOR DIVER EMERGENCY SUPPORT. A MEDICAL STAFF IS LOCATED ON THE MARSHALL SPACE FLIGHT CENTER (MSFC) AND SUPPORTS THE NBS PERSONNEL WHEN HYPERBARIC CHAMBER OPERATION IS NECESSARY. - Marshall Space Flight Center, Neutral Buoyancy Simulator Facility, Rideout Road, Huntsville, Madison County, AL

Semiclosed-circuit atmosphere control in a portable recompression chamber

NASA Technical Reports Server (NTRS)

Riegel, P. S.; Caudy, D. W.

1972-01-01

A small portable recompression chamber is described that can be used both to treat a diver for decompression sickness or to transport him to a larger chamber complex. The device can be operated in either open circuit or semiclosed circuit atmospheres, permits two way conversation between patient and attendant, and uses an air injector for circulation of the chamber atmosphere.

Comparison of Reef Fish Survey Data Gathered by Open and Closed Circuit SCUBA Divers Reveals Differences in Areas With Higher Fishing Pressure

PubMed Central

Stamoulis, Kostantinos A.; Boland, Raymond C.; Lino, Kevin C.; Hauk, Brian B.; Leonard, Jason C.; Asher, Jacob M.; Lopes, Keolohilani H.; Kosaki, Randall K.

2016-01-01

Visual survey by divers using open-circuit (OC) SCUBA is the most widely used approach to survey coral reef fishes. Therefore, it is important to quantify sources of bias in OC surveys, such as the possibility that avoidance of OC divers by fishes can lead to undercounting in areas where targeted species have come to associate divers with a risk of being speared. One potential way to reduce diver avoidance is to utilize closed circuit rebreathers (CCRs), which do not produce the noise and bubbles that are a major source of disturbance associated with OC diving. For this study, we conducted 66 paired OC and CCR fish surveys in the Main Hawaiian Islands at locations with relatively high, moderate, and light fishing pressure. We found no significant differences in biomass estimates between OC and CCR surveys when data were pooled across all sites, however there were differences at the most heavily fished location, Oahu. There, biomass estimates from OC divers were significantly lower for several targeted fish groups, including surgeonfishes, targeted wrasses, and snappers, as well as for all targeted fishes combined, with mean OC biomass between 32 and 68% of mean CCR biomass. There were no clear differences between OC and CCR biomass estimates for these groups at sites with moderate or low fishing pressure, or at any location for other targeted fish groups, including groupers, parrotfishes, and goatfishes. Bias associated with avoidance of OC divers at heavily fished locations could be substantially reduced, or at least calibrated for, by utilization of CCR. In addition to being affected by fishing pressure, the extent to which avoidance of OC divers is problematic for visual surveys varies greatly among taxa, and is likely to be highly influenced by the survey methodology and dimensions used. PMID:27936044

Comparison of Reef Fish Survey Data Gathered by Open and Closed Circuit SCUBA Divers Reveals Differences in Areas With Higher Fishing Pressure.

PubMed

Gray, Andrew E; Williams, Ivor D; Stamoulis, Kostantinos A; Boland, Raymond C; Lino, Kevin C; Hauk, Brian B; Leonard, Jason C; Rooney, John J; Asher, Jacob M; Lopes, Keolohilani H; Kosaki, Randall K

2016-01-01

Visual survey by divers using open-circuit (OC) SCUBA is the most widely used approach to survey coral reef fishes. Therefore, it is important to quantify sources of bias in OC surveys, such as the possibility that avoidance of OC divers by fishes can lead to undercounting in areas where targeted species have come to associate divers with a risk of being speared. One potential way to reduce diver avoidance is to utilize closed circuit rebreathers (CCRs), which do not produce the noise and bubbles that are a major source of disturbance associated with OC diving. For this study, we conducted 66 paired OC and CCR fish surveys in the Main Hawaiian Islands at locations with relatively high, moderate, and light fishing pressure. We found no significant differences in biomass estimates between OC and CCR surveys when data were pooled across all sites, however there were differences at the most heavily fished location, Oahu. There, biomass estimates from OC divers were significantly lower for several targeted fish groups, including surgeonfishes, targeted wrasses, and snappers, as well as for all targeted fishes combined, with mean OC biomass between 32 and 68% of mean CCR biomass. There were no clear differences between OC and CCR biomass estimates for these groups at sites with moderate or low fishing pressure, or at any location for other targeted fish groups, including groupers, parrotfishes, and goatfishes. Bias associated with avoidance of OC divers at heavily fished locations could be substantially reduced, or at least calibrated for, by utilization of CCR. In addition to being affected by fishing pressure, the extent to which avoidance of OC divers is problematic for visual surveys varies greatly among taxa, and is likely to be highly influenced by the survey methodology and dimensions used.

Anaerobic co-digestion of dairy manure and potato waste

NASA Astrophysics Data System (ADS)

Yadanaparthi, Sai Krishna Reddy

Dairy and potato are two important agricultural commodities in Idaho. Both the dairy and potato processing industries produce a huge amount of waste which could cause environmental pollution. To minimize the impact of potential pollution associated with dairy manure (DM) and potato waste (PW), anaerobic co-digestion has been considered as one of the best treatment process. The purpose of this research is to evaluate the anaerobic co-digestion of dairy manure and potato waste in terms of process stability, biogas generation, construction and operating costs, and potential revenue. For this purpose, I conducted 1) a literature review, 2) a lab study on anaerobic co-digestion of dairy manure and potato waste at three different temperature ranges (ambient (20-25°C), mesophilic (35-37°C) and thermophilic (55-57°C) with five mixing ratios (DM:PW-100:0, 90:10, 80:20, 60:40, 40:60), and 3) a financial analysis for anaerobic digesters based on assumed different capital costs and the results from the lab co-digestion study. The literature review indicates that several types of organic waste were co-digested with DM. Dairy manure is a suitable base matter for the co-digestion process in terms of digestion process stability and methane (CH4) production (Chapter 2). The lab tests showed that co-digestion of DM with PW was better than digestion of DM alone in terms of biogas and CH4 productions (Chapter 3). The financial analysis reveals DM and PW can be used as substrate for full size anaerobic digesters to generate positive cash flow within a ten year time period. Based on this research, the following conclusions and recommendations were made: ▸ The ratio of DM:PW-80:20 is recommended at thermophilic temperatures and the ratio of DM:PW-90:10 was recommended at mesophilic temperatures for optimum biogas and CH4 productions. ▸ In cases of anaerobic digesters operated with electricity generation equipment (generators), low cost plug flow digesters (capital cost of 600/cow) operating at thermophilic temperatures are recommended. • The ratio of DM:PW-90:10 or 80:20 is recommended while operating low cost plug flow digesters at thermophilic temperatures. ▸ In cases of anaerobic digesters operated without electricity generation equipment (generators), completely mixed or high or low cost plug flow digesters can be used. • The ratio of DM:PW-80:20 is recommended for completely mixed digesters operated at thermophilic temperatures; • The ratio of DM:PW-90:10 or 80:20 is recommended for high cost plug flow digesters (capital cost of 1,000/cow) operated at thermophilic temperatures; • All of the four co-digested mixing ratios (i.e. DM:PW-90:10 or 80:20 or 60:40 or 40:60) are good for low cost plug flow digesters (capital cost of $600/cow) operated at thermophilic temperatures. The ratio of DM:PW-90:10 is recommended for positive cash flow within the ten year period if the low cost plug flow digesters are operated at mesophilic temperatures.

Coil-On-Plug Ignition for Oxygen/Methane Liquid Rocket Engines in Thermal-Vacuum Environments

NASA Technical Reports Server (NTRS)

Melcher, John C.; Atwell, Matthew J.; Morehead, Robert L.; Hurlbert, Eric A.; Bugarin, Luz; Chaidez, Mariana

2017-01-01

A coil-on-plug ignition system has been developed and tested for Liquid Oxygen (LOX)/liquid methane (LCH4) rocket engines operating in thermal vacuum conditions. The igniters were developed and tested as part of the Integrated Cryogenic Propulsion Test Article (ICPTA), previously tested as part of the Project Morpheus test vehicle. The ICPTA uses an integrated, pressure-fed, cryogenic LOX/LCH4 propulsion system including a reaction control system (RCS) and a main engine. The ICPTA was tested at NASA Glenn Research Center's Plum Brook Station in the Spacecraft Propulsion Research Facility (B-2) under vacuum and thermal vacuum conditions. A coil-on-plug ignition system has been developed to successfully demonstrate ignition reliability at these conditions while preventing corona discharge issues. The ICPTA uses spark plug ignition for both the main engine igniter and the RCS. The coil-on-plug configuration eliminates the conventional high-voltage spark plug cable by combining the coil and the spark plug into a single component. Prior to ICPTA testing at Plum Brook, component-level reaction control engine (RCE) and main engine igniter testing was conducted at NASA Johnson Space Center (JSC), which demonstrated successful hot-fire ignition using the coil-on-plug from sea-level ambient conditions down to 10(exp -2) torr. Integrated vehicle hot-fire testing at JSC demonstrated electrical and command/data system performance. Lastly, hot-fire testing at Plum Brook demonstrated successful ignitions at simulated altitude conditions at 30 torr and cold thermal-vacuum conditions at 6 torr. The test campaign successfully proved that coil-on-plug technology will enable integrated LOX/LCH4 propulsion systems in future spacecraft.

Coil-On-Plug Ignition for LOX/Methane Liquid Rocket Engines in Thermal Vacuum Environments

NASA Technical Reports Server (NTRS)

Melcher, John C.; Atwell, Matthew J.; Morehead, Robert L.; Hurlbert, Eric A.; Bugarin, Luz; Chaidez, Mariana

2017-01-01

A coil-on-plug ignition system has been developed and tested for Liquid Oxygen (LOX) / liquid methane rocket engines operating in thermal vacuum conditions. The igniters were developed and tested as part of the Integrated Cryogenic Propulsion Test Article (ICPTA), previously tested as part of the Project Morpheus test vehicle. The ICPTA uses an integrated, pressure-fed, cryogenic LOX/methane propulsion system including a reaction control system (RCS) and a main engine. The ICPTA was tested at NASA Glenn Research Center's Plum Brook Station in the Spacecraft Propulsion Research Facility (B-2) under vacuum and thermal vacuum conditions. In order to successfully demonstrate ignition reliability in the vacuum conditions and eliminate corona discharge issues, a coil-on-plug ignition system has been developed. The ICPTA uses spark-plug ignition for both the main engine igniter and the RCS. The coil-on-plug configuration eliminates the conventional high-voltage spark plug cable by combining the coil and the spark-plug into a single component. Prior to ICPTA testing at Plum Brook, component-level reaction control engine (RCE) and main engine igniter testing was conducted at NASA Johnson Space Center (JSC), which demonstrated successful hot-fire ignition using the coil-on-plug from sea-level ambient conditions down to 10(exp.-2) torr. Integrated vehicle hot-fire testing at JSC demonstrated electrical and command/data system performance. Lastly, Plum Brook testing demonstrated successful ignitions at simulated altitude conditions at 30 torr and cold thermal-vacuum conditions at 6 torr. The test campaign successfully proved that coil-on-plug technology will enable integrated LOX/methane propulsion systems in future spacecraft.

Sink or Swim: The Cartesian Diver.

ERIC Educational Resources Information Center

Pinkerton, K. David

2001-01-01

Presents the activity of Cartesian divers which demonstrates the relationship between pressure, temperature, volume, and buoyancy. Includes both instructor information and student activity sheet. (YDS)

25 CFR 226.22 - Prohibition of pollution.

Code of Federal Regulations, 2014 CFR

2014-04-01

... all times conduct their operations and drill, equip, operate, produce, plug and abandon all wells drilled for oil or gas, service wells or exploratory wells (including seismic, core and stratigraphic... LANDS FOR OIL AND GAS MINING Operations § 226.22 Prohibition of pollution. (a) All operators...

25 CFR 226.22 - Prohibition of pollution.

Code of Federal Regulations, 2013 CFR

2013-04-01

... all times conduct their operations and drill, equip, operate, produce, plug and abandon all wells drilled for oil or gas, service wells or exploratory wells (including seismic, core and stratigraphic... LANDS FOR OIL AND GAS MINING Operations § 226.22 Prohibition of pollution. (a) All operators...

25 CFR 226.22 - Prohibition of pollution.

Code of Federal Regulations, 2012 CFR

2012-04-01

... all times conduct their operations and drill, equip, operate, produce, plug and abandon all wells drilled for oil or gas, service wells or exploratory wells (including seismic, core and stratigraphic... LANDS FOR OIL AND GAS MINING Operations § 226.22 Prohibition of pollution. (a) All operators...

Dysbaric Osteonecrosis in Divers. 1. A Survey of 611 Selected U. S. Navy Divers

DTIC Science & Technology

1976-02-24

ed., Academic Press, New York, 1971, pp 251- 262. 10 7. Asahi, S. H. Ohiwa, and I. Nashimoto, " Avascular Bone Necrosis in Japanese Diving...bone necrosis has been confirmed. 4>5 The confirmation of aseptic bone necrosis in Caisson workers prompted several studies of divers to determine...de- scribe the radiological observations of bone density and structure variations which appear to be aseptic bone necrosis occurring in

Measurement of fatigue following 18 msw dry chamber dives breathing air or enriched air nitrox.

PubMed

Harris, R J D; Doolette, D J; Wilkinson, D C; Williams, D J

2003-01-01

Many divers report less fatigue following diving breathing oxygen rich N2-O2 mixtures compared with breathing air. In this double blinded, randomized controlled study 11 divers breathed either air or Enriched Air Nitrox 36% (oxygen 36%, nitrogen 64%) during an 18 msw (281 kPa(a)) dry chamber dive for a bottom time of 40 minutes. Two periods of exercise were performed during the dive. Divers were assessed before and after each dive using the Multidimensional Fatigue Inventory-20, a visual analogue scale, Digit Span Tests, Stroop Tests, and Divers Health Survey (DHS). Diving to 18m produced no measurable difference in fatigue, attention levels, ability to concentrate or DHS scores, following dives using either breathing gas.

Signal processing for passive detection and classification of underwater acoustic signals

NASA Astrophysics Data System (ADS)

Chung, Kil Woo

2011-12-01

This dissertation examines signal processing for passive detection, classification and tracking of underwater acoustic signals for improving port security and the security of coastal and offshore operations. First, we consider the problem of passive acoustic detection of a diver in a shallow water environment. A frequency-domain multi-band matched-filter approach to swimmer detection is presented. The idea is to break the frequency contents of the hydrophone signals into multiple narrow frequency bands, followed by time averaged (about half of a second) energy calculation over each band. Then, spectra composed of such energy samples over the chosen frequency bands are correlated to form a decision variable. The frequency bands with highest Signal/Noise ratio are used for detection. The performance of the proposed approach is demonstrated for experimental data collected for a diver in the Hudson River. We also propose a new referenceless frequency-domain multi-band detector which, unlike other reference-based detectors, does not require a diver specific signature. Instead, our detector matches to a general feature of the diver spectrum in the high frequency range: the spectrum is roughly periodic in time and approximately flat when the diver exhales. The performance of the proposed approach is demonstrated by using experimental data collected from the Hudson River. Moreover, we present detection, classification and tracking of small vessel signals. Hydroacoustic sensors can be applied for the detection of noise generated by vessels, and this noise can be used for vessel detection, classification and tracking. This dissertation presents recent improvements aimed at the measurement and separation of ship DEMON (Detection of Envelope Modulation on Noise) acoustic signatures in busy harbor conditions. Ship signature measurements were conducted in the Hudson River and NY Harbor. The DEMON spectra demonstrated much better temporal stability compared with the full ship spectra and were measured at distances up to 7 km. The combination of cross-correlation and DEMON methods allows separation of the acoustic signatures of ships in busy urban environments. Finally, we consider the extension of this algorithm for vessel tracking using phase measurement of the DEMON signal recorded by two or more hydrophones. Tests conducted in the Hudson River and NY Bay confirmed opportunity of Direction of Arrival (DOA) funding using the phase DEMON method.

The effectiveness of plug-in hybrid electric vehicles and renewable power in support of holistic environmental goals: Part 2 - Design and operation implications for load-balancing resources on the electric grid

NASA Astrophysics Data System (ADS)

Tarroja, Brian; Eichman, Joshua D.; Zhang, Li; Brown, Tim M.; Samuelsen, Scott

2015-03-01

A study has been performed that analyzes the effectiveness of utilizing plug-in vehicles to meet holistic environmental goals across the combined electricity and transportation sectors. In this study, plug-in hybrid electric vehicle (PHEV) penetration levels are varied from 0 to 60% and base renewable penetration levels are varied from 10 to 63%. The first part focused on the effect of installing plug-in hybrid electric vehicles on the environmental performance of the combined electricity and transportation sectors. The second part addresses impacts on the design and operation of load-balancing resources on the electric grid associated with fleet capacity factor, peaking and load-following generator capacity, efficiency, ramp rates, start-up events and the levelized cost of electricity. PHEVs using smart charging are found to counteract many of the disruptive impacts of intermittent renewable power on balancing generators for a wide range of renewable penetration levels, only becoming limited at high renewable penetration levels due to lack of flexibility and finite load size. This study highlights synergy between sustainability measures in the electric and transportation sectors and the importance of communicative dispatch of these vehicles.

Health Survey of U.S. Navy Divers from 1960 to 1990: A First Look

DTIC Science & Technology

2011-09-01

Married divers represented 87% of the participants; divorced or widowed, 11%; and never married, 1%. Of all these divers, 60% now receive disability ...care and benefits for what they feel are “service-connected” health problems related to their participation in activities during those careers. These...diving but not related to unsafe practice.” “Long-term,” this statement continues, is defined as “persisting beyond the acute phase and rehabilitation

Time to stop mucking around? Impacts of underwater photography on cryptobenthic fauna found in soft sediment habitats.

PubMed

De Brauwer, Maarten; Saunders, Benjamin J; Ambo-Rappe, Rohani; Jompa, Jamaluddin; McIlwain, Jennifer L; Harvey, Euan S

2018-07-15

Scuba diving tourism is a sustainable source of income for many coastal communities, but can have negative environmental impacts if not managed effectively. Diving on soft sediment habitats, typically referred to as 'muck diving', is a growing multi-million dollar industry with a strong focus on photographing cryptobenthic fauna. We assessed how the environmental impacts of scuba divers are affected by the activity they are engaged in while diving and the habitat they dive in. To do this, we observed 66 divers on coral reefs and soft sediment habitats in Indonesia and the Philippines. We found diver activity, specifically interacting with and photographing fauna, causes greater environmental disturbances than effects caused by certification level, gender, dive experience or age. Divers touched the substrate more often while diving on soft sediment habitats than on coral reefs, but this did not result in greater environmental damage on soft sediment sites. Divers had a higher impact on the substrate and touch animals more frequently when observing or photographing cryptobenthic fauna. When using dSLR-cameras, divers spent up to five times longer interacting with fauna. With the unknown, long-term impacts on cryptobenthic fauna or soft sediment habitats, and the increasing popularity of underwater photography, we argue for the introduction of a muck diving code of conduct. Copyright © 2018 Elsevier Ltd. All rights reserved.

Brief communication: Self-reported health and activity habits and attitudes in saturation divers.

PubMed

Dolan, Eimear; Deb, Sanjoy; Stephen, Graeme; Swinton, Paul

2016-01-01

Exposure to the confined hyperbaric, hyperoxic environment of the saturation chamber poses a number of unique physiological challenges to divers. Appropriately tailored training, nutrition and health programs may help support the body to cope with and overcome these challenges. To describe the self-reported habits and attitudes of saturation divers toward issues related to health, lifestyle, nutrition and physical activity. A questionnaire was developed to elicit information related to four key areas: 1) respondent demographics; 2) physical activity habits and attitudes; 3) nutritional attitudes; and 4) general lifestyle and health information. Respondents (n = 89/45%) reported a generally healthy lifestyle, including high physical activity levels while onshore, low tobacco use and alcohol intakes within U.K.-recommended guidelines. Responses to in-chamber items demonstrated reduced physical activity, disrupted sleep and distorted taste and smell perception. In addition, lethargy, headaches and musculoskeletal stiffness/soreness were reported as frequent symptoms following a period of time spent in saturation. Results of this study provide an in-sight into the self-reported practices and attitudes of saturation divers and appear to indicate a generally healthy lifestyle in the respondents. Some themes emerged which may impact on diver health and performance while in saturation. The results of this report may help provide a platform to generate hypotheses for further research and facilitate development of appropriately tailored nutrition and training-based strategies for saturation divers.

A comparison between boat-based and diver-based methods for quantifying coral bleaching

USGS Publications Warehouse

Zawada, David G.; Ruzicka, Rob; Colella, Michael A.

2015-01-01

Recent increases in both the frequency and severity of coral bleaching events have spurred numerous surveys to quantify the immediate impacts and monitor the subsequent community response. Most of these efforts utilize conventional diver-based methods, which are inherently time-consuming, expensive, and limited in spatial scope unless they deploy large teams of scientifically-trained divers. In this study, we evaluated the effectiveness of the Along-Track Reef Imaging System (ATRIS), an automated image-acquisition technology, for assessing a moderate bleaching event that occurred in the summer of 2011 in the Florida Keys. More than 100,000 images were collected over 2.7 km of transects spanning four patch reefs in a 3-h period. In contrast, divers completed 18, 10-m long transects at nine patch reefs over a 5-day period. Corals were assigned to one of four categories: not bleached, pale, partially bleached, and bleached. The prevalence of bleaching estimated by ATRIS was comparable to the results obtained by divers, but only for corals > 41 cm in size. The coral size-threshold computed for ATRIS in this study was constrained by prevailing environmental conditions (turbidity and sea state) and, consequently, needs to be determined on a study-by-study basis. Both ATRIS and diver-based methods have innate strengths and weaknesses that must be weighed with respect to project goals.

In-use measurement of activity, energy use, and emissions of a plug-in hybrid electric vehicle.

PubMed

Graver, Brandon M; Frey, H Christopher; Choi, Hyung-Wook

2011-10-15

Plug-in hybrid electric vehicles (PHEVs) could reduce transportation air emissions and energy use. However, a method is needed for estimating on-road emissions of PHEVs. To develop a framework for quantifying microscale energy use and emissions (EU&E), measurements were conducted on a Toyota Prius retrofitted with a plug-in battery system on eight routes. Measurements were made using the following: (1) a data logger for the hybrid control system; (2) a portable emissions measurement system; and (3) a global positioning system with barometric altimeter. Trends in EU&E are estimated based on vehicle specific power. Energy economy is quantified based on gasoline consumed by the engine and grid energy consumed by the plug-in battery. Emissions from electricity consumption are estimated based on the power generation mix. Fuel use is approximately 30% lower during plug-in battery use. Grid emissions were higher for CO₂, NO(x), SO₂, and PM compared to tailpipe emissions but lower for CO and hydrocarbons. EU&E depends on engine and plug-in battery operation. The use of two energy sources must be addressed in characterizing fuel economy; overall energy economy is 11% lower if including grid energy use than accounting only for fuel consumption.

Achieve efficient nitrogen removal from real sewage in a plug-flow integrated fixed-film activated sludge (IFAS) reactor via partial nitritation/anammox pathway.

PubMed

Yang, Yandong; Zhang, Liang; Cheng, Jun; Zhang, Shujun; Li, Baikun; Peng, Yongzhen

2017-09-01

This study tested the feasibility of plug-flow integrated fixed-film activated sludge (IFAS) reactor in applying sewage partial nitritation/anammox (PN/A) process. The IFAS reactor was fed with real pre-treated sewage (C/N ratio=1.3) and operated for 200days. High nitrogen removal efficiency of 82% was achieved with nitrogen removal rates of 0.097±0.019kgN/(m 3 ·d). Therefore, plug-flow IFAS reactor could be an alternative to applying sewage PN/A process. Besides, it was found that the stability of sewage PN/A process was significantly affected by residual ammonium. Nitrate accumulated in effluent and PN/A performance deteriorated when residual ammonium was below 1mg/L. On the contrary, long-term stable PN/A operation was achieved when residual ammonium was over 3mg/L. Copyright © 2017 Elsevier Ltd. All rights reserved.

Effects of oxygen-enriched air on cognitive performance during SCUBA-diving - an open-water study.

PubMed

Brebeck, Anne-Kathrin; Deussen, Andreas; Schmitz-Peiffer, Henning; Range, Ursula; Balestra, Costantino; Cleveland, Sinclair; Schipke, Jochen D

2017-01-01

Backround: Nitrogen narcosis impairs cognitive function, a fact relevant during SCUBA-diving. Oxygen-enriched air (nitrox) became popular in recreational diving, while evidence of its advantages over air is limited. Compare effects of nitrox28 and air on two psychometric tests. In this prospective, double-blind, open-water study, 108 advanced divers (38 females) were randomized to an air or a nitrox-group for a 60-min dive to 24 m salt water. Breathing gas effects on cognitive performance were assessed during the dive using a short- and long-term memory test and a number connection test. Nitrox28 divers made fewer mistakes only on the long-term memory test (p = 0.038). Female divers remembered more items than male divers (p < 0.001). There were no significant differences in the number connection test between the groups. Likely owing to the comparatively low N 2 reduction and the conservative dive, beneficial nitrox28 effects to diver performance were moderate but could contribute to diving safety.

Porous plug phase separator and superfluid film flow suppression system for the soft x-ray spectrometer onboard ASTRO-H

NASA Astrophysics Data System (ADS)

Ezoe, Yuichiro; Ishikawa, Kumi; Mitsuishi, Ikuyuki; Ohashi, Takaya; Mitsuda, Kazuhisa; Fujimoto, Ryuichi; Murakami, Masahide; Kanao, Kenichi; Yoshida, Seiji; Tsunematsu, Shoji; DiPirro, Michael; Shirron, Peter

2016-07-01

Suppression of super fluid helium flow is critical for the Soft X-ray Spectrometer onboard ASTRO-H (Hitomi). In nominal operation, a small helium gas flow of 30 μg/s must be safely vented and a super fluid film flow must be sufficiently small <2 μg/s. To achieve a life time of the liquid helium, a porous plug phase separator and a film flow suppression system composed of an orifice, a heat exchanger, and knife edge devices are employed. In this paper, design, on-ground testing results and in-orbit performance of the porous plug and the film flow suppression system are described.

Mind Your Risks

MedlinePlus

... Diver Poster Rock Climber Poster Sky Diver Poster Social Media Graphics ... THE CAMPAIGN Mind Your Risks® is a public health campaign that educates people with high blood pressure about the importance of ...

Plug-in hybrid electric vehicle LiFePO4 battery life implications of thermal management, driving conditions, and regional climate

NASA Astrophysics Data System (ADS)

Yuksel, Tugce; Litster, Shawn; Viswanathan, Venkatasubramanian; Michalek, Jeremy J.

2017-01-01

Battery degradation strongly depends on temperature, and many plug-in electric vehicle applications employ thermal management strategies to extend battery life. The effectiveness of thermal management depends on the design of the thermal management system as well as the battery chemistry, cell and pack design, vehicle system characteristics, and operating conditions. We model a plug-in hybrid electric vehicle with an air-cooled battery pack composed of cylindrical LiFePO4/graphite cells and simulate the effect of thermal management, driving conditions, regional climate, and vehicle system design on battery life. We estimate that in the absence of thermal management, aggressive driving can cut battery life by two thirds; a blended gas/electric-operation control strategy can quadruple battery life relative to an all-electric control strategy; larger battery packs can extend life by an order of magnitude relative to small packs used for all-electric operation; and batteries last 73-94% longer in mild-weather San Francisco than in hot Phoenix. Air cooling can increase battery life by a factor of 1.5-6, depending on regional climate and driving patterns. End of life criteria has a substantial effect on battery life estimates.

Scuba Weights

NASA Technical Reports Server (NTRS)

1995-01-01

The Attitude Adjuster is a system for weight repositioning corresponding to a SCUBA diver's changing positions. Compact tubes on the diver's air tank permit controlled movement of lead balls within the Adjuster, automatically repositioning when the diver changes position. Manufactured by Think Tank Technologies, the system is light and small, reducing drag and energy requirements and contributing to lower air consumption. The Mid-Continent Technology Transfer Center helped the company with both technical and business information and arranged for the testing at Marshall Space Flight Center's Weightlessness Environmental Training Facility for astronauts.

Neurologic outcome of controlled compressed-air diving.

PubMed

Cordes, P; Keil, R; Bartsch, T; Tetzlaff, K; Reuter, M; Hutzelmann, A; Friege, L; Meyer, T; Bettinghausen, E; Deuschl, G

2000-12-12

The authors compared the neurologic, neuropsychological, and neuroradiologic status of military compressed-air divers without a history of neurologic decompression illness and controls. No gross differences in the neuropsychometric test results or abnormal neurologic findings were found. There was no correlation between test results, diving experience, and number and size of cerebral MRI lesions. Prevalence of cerebral lesions was not increased in divers. These results suggest that there are no long-term CNS sequelae in military divers if diving is performed under controlled conditions.

76 FR 66090 - Facility Operating License Amendment From Virginia Electric and Power Company, Surry Power...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-10-25

... operating pressures, leakage from primary water stress corrosion cracking below the proposed limited... discussed in Regulatory Guide (RG) 1.121, ``Bases for Plugging Degraded PWR [Pressurized-Water Reactor...

Pacific Gas & Electric Plug-In Hybrid Electric Utility Truck Testing |

Science.gov Websites

improving efficiency and decreasing emissions during various modes of operation NREL results will help issues and requirements associated with vehicle operation, and fine-tune the design of such vehicles

Morphometrics of the avian lung. 4. The structural design of the charadriiform lung.

PubMed

Maina, J N

1987-04-01

The lungs of five charadriiform species of bird, two of which are good divers and three predominantly flyers (soarers and gliders) have been analysed by morphometric techniques. Largely the morphometric structural values in the divers significantly exceeded those of the flyers (gulls). The average weight specific surface area of the blood-gas (tissue) barrier in the divers (28.45 +/- 2.05 cm2 X g-1 SD) surpassed that of the flyers (23.5 +/- 3.61 cm2 X g-1 SD). The divers had a higher volume of the pulmonary capillary blood per unit body weight (4.42 +/- 0.11 cm3 X kg-1 SD) than the flyers (2.84 +/- 0.58 cm3 X kg-1 SD). The weight specific volume of the lung in the divers (34.90 +/- 3.11 cm3 X kg-1 SD) exceeded that of the flyers (26.94 +/- 3.15 cm3 X kg-1 SD). The total morphometric pulmonary diffusing capacity per unit body weight in the divers (4.73 +/- 0.05 ml O2 X (min X mm Hg X kg)-1 SD) was higher than that of the flyers (3.09 +/- 0.47 ml O2 X (min X mm Hg X kg)-1 SD). The divers, however, had a notably thicker blood-gas (tissue) barrier with a harmonic mean thickness of 0.212 +/- 0.03 micron SD compared to that of the flyers (0.138 +/- 0.02 micron SD). The data acquired here commensurate the modes of life exhibited by these two groups of bird. The divers, which are relatively energetic birds, expend a lot of energy to move and stay underwater, concomitantly undergoing prolonged asphyxia during submergence and may hence need to extract as much of the oxygen in the pulmonary air as possible to prolong a dive. These birds appear in general to have structurally better adapted lungs than those of the gulls, birds which to a large extent exhibit relatively less energetic soaring and gliding flights.

Orion's Neutral Buoyancy Lab (NBL) Activities

NASA Image and Video Library

2016-09-21

Tim Goddard, center, NASA Open Water Recovery Operations director, briefs U.S. Navy divers, Air Force pararescuemen and Coast Guard rescue swimmers during training in the Neutral Buoyancy Laboratory at NASA’s Johnson Space Center in Houston. The group will practice Orion underway recovery techniques using a test version of the Orion spacecraft. Training will help the team prepare for Underway Recovery Test 5 for Exploration Mission 1 aboard the USS San Diego in the Pacific Ocean off the coast of California in October. The Ground Systems Development and Operations Program, along with the U.S. Navy and Lockheed Martin, are preparing the recovery team, hardware and operations to support EM-1 recovery.

Undersea applications of dexterous robotics

NASA Technical Reports Server (NTRS)

Gittleman, Mark M.

1994-01-01

The revolution and application of dexterous robotics in the undersea energy production industry and how this mature technology has affected planned SSF dexterous robotic tasks are examined. Undersea telerobotics, or Remotely Operated Vehicles (ROV's), have evolved in design and use since the mid-1970s. Originally developed to replace commercial divers for both planned and unplanned tasks, they are now most commonly used to perform planned robotic tasks in all phases of assembly, inspection, and maintenance of undersea structures and installations. To accomplish these tasks, the worksites, the tasks themselves, and the tools are now engineered with both the telerobot's and the diver's capabilities in mind. In many cases, this planning has permitted a reduction in telerobot system complexity and cost. The philosophies and design practices that have resulted in the successful incorporation of telerobotics into the highly competitive and cost conscious offshore production industry have been largely ignored in the space community. Cases where these philosophies have been adopted or may be successfully adopted in the near future are explored.

5 CFR 532.281 - Special wage schedules for divers and tenders.

Code of Federal Regulations, 2010 CFR

2010-01-01

... REGULATIONS PREVAILING RATE SYSTEMS Prevailing Rate Determinations § 532.281 Special wage schedules for divers and tenders. (a) Agencies are authorized to establish special schedule payments for prevailing rate...

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

PubMed

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.

The use of drugs by UK recreational divers: illicit drugs.

PubMed

Dowse, Marguerite St Leger; Shaw, Steve; Cridge, Christine; Smerdon, Gary

2011-03-01

Anecdotal observations suggest the use of illicit drugs takes place amongst recreational divers but, to date, there has been little open debate within the diving community concerning possible prevalence. This study investigated the prevalence and type of illicit drugs used by recreational divers in the United Kingdom (UK). Anonymous questionnaires were circulated via UK dive clubs, dive schools, dive shows and conferences. Questions incorporated diver and diving demographics and general health, which included anxiety, depression and panic attacks, alcohol use, smoking and illicit drug use since learning to dive and closest time to a dive. Questions pertaining to over-the-counter and prescription drug use were also asked. 479 divers responded (66% males and 34% females) in the age range 16 to 59 years. Of the respondents, 22% had used one or more illicit drug since learning to dive, reporting benzodiazepines, amphetamines, cocaine, ecstasy, LSD, cannabis, heroin, and 'magic mushrooms'. Illicit drugs had been used by 3.5% of respondents in the last 12 months, and 3% in the last month. Cannabis, cocaine and ecstasy use was reported within 6 hours of a dive. Logistic regression confirmed a relationship between illicit drug use and depression (P = 0.014), and also between illicit drug use and anxiety (P = 0.024). These data support anecdotal reports that recreational divers use a range of illicit drugs. The significant relationship between illicit drug use and depression and anxiety supports the literature in non-diving populations.

Prevalence and causes of loss of consciousness in former North Sea occupational divers.

PubMed

Sundal, Endre; Irgens, Ågot; Troland, Kari; Thorsen, Einar; Grønning, Marit

2013-01-01

Loss of consciousness (LOC) is a serious event during diving. The purpose of this study wasto estimate the prevalence and causes of LOC during diving in former North Sea divers, and the impacton health-related quality of life. Up to 1990 a total of 373 Norwegian offshore divers worked in the North Sea. From 2000 to 2011, 221 of these were referred to the Department of Occupational Medicine at Haukeland University Hospital for examination due to health complaints. They filled in a questionnaire for registration of diving experience and health complaints, including the SF-36 version 1 for the assessment of quality oflife. The questionnaire and the hospital records were systematically reviewed by 2 independent observers. Episodes of LOC during diving and the causes were registered. All participants underwent a clinical neurological examination. Electroencephalogram (EEG) and the event-related brain potential (P300) were recorded. One or more episodes of LOC were reported by 58 of 219 divers. LOC due to gas cut was reportedby 27 of these. Divers having experienced LOC due to gas cut had lower SF-36 sub-scores then the rest of the diving population. EEG and P300 recordings did not differ between the groups. A high proportion of former Norwegian North Sea divers reported episodes of LOC, for whichgas cut was the most common cause. Both hypoxia and peritraumatic stress associated with the episodecould have a long term impact on the quality of life. Neurophysiological functions, however, did not differbetween the groups.

Underwater speech communications with a modulated laser

NASA Astrophysics Data System (ADS)

Woodward, B.; Sari, H.

2008-04-01

A novel speech communications system using a modulated laser beam has been developed for short-range applications in which high directionality is an exploitable feature. Although it was designed for certain underwater applications, such as speech communications between divers or between a diver and the surface, it may equally be used for air applications. With some modification it could be used for secure diver-to-diver communications in the situation where untethered divers are swimming close together and do not want their conversations monitored by intruders. Unlike underwater acoustic communications, where the transmitted speech may be received at ranges of hundreds of metres omnidirectionally, a laser communication link is very difficult to intercept and also obviates the need for cables that become snagged or broken. Further applications include the transmission of speech and data, including the short message service (SMS), from a fixed installation such as a sea-bed habitat; and data transmission to and from an autonomous underwater vehicle (AUV), particularly during docking manoeuvres. The performance of the system has been assessed subjectively by listening tests, which revealed that the speech was intelligible, although of poor quality due to the speech algorithm used.

Progress on ITER Diagnostic Integration

NASA Astrophysics Data System (ADS)

Johnson, David; Feder, Russ; Klabacha, Jonathan; Loesser, Doug; Messineo, Mike; Stratton, Brentley; Wood, Rick; Zhai, Yuhu; Andrew, Phillip; Barnsley, Robin; Bertschinger, Guenter; Debock, Maarten; Reichle, Roger; Udintsev, Victor; Vayakis, George; Watts, Christopher; Walsh, Michael

2013-10-01

On ITER, front-end components must operate reliably in a hostile environment. Many will be housed in massive port plugs, which also shield the machine from radiation. Multiple diagnostics reside in a single plug, presenting new challenges for developers. Front-end components must tolerate thermally-induced stresses, disruption-induced mechanical loads, stray ECH radiation, displacement damage, and degradation due to plasma-induced coatings. The impact of failures is amplified due to the difficulty in performing robotic maintenance on these large structures. Motivated by needs to minimize disruption loads on the plugs, standardize the handling of shield modules, and decouple the parallel efforts of the many parties, the packaging strategy for diagnostics has recently focused on the use of 3 vertical shield modules inserted from the plasma side into each equatorial plug structure. At the front of each is a detachable first wall element with customized apertures. Progress on US equatorial and upper plugs will be used as examples, including the layout of components in the interspace and port cell regions. Supported by PPPL under contract DE-AC02-09CH11466 and UT-Battelle, LLC under contract DE-AC05-00OR22725 with the U.S. DOE.

Operational Considerations for the Standby Diver in CUMA Dives

DTIC Science & Technology

2010-11-01

avec ACDSM R.Y. Nishi; A.J. Ward; D.J. Eaton; DRDC Toronto TM 2010-082; R & D pour la défense Canada – Toronto; Novembre 2010. Introduction ou...11  Figure A-5. Computed inert gas loading in first and second compartments for 5 min at 9 msw .. 13 ... 13   Figure A-7. Computed inert gas loading in first and second compartments for 30

Neuropsychometric Test in Royal Netherlands Navy Mine-Clearance Divers

DTIC Science & Technology

2001-06-01

Issues in Hypo-and Hyperbaric Conditions [les Questions medicales a caractere oprationel liees aux conditions hypobares ou hyperbares ] To order the...Digit Memo Sjan Test (F/B DMST-F/B Learnin /memoie Paper presented at the RTO HFM Symposium on "Operational Medical Issues in Hypo- and Hyperbaric ... Hyperbaric Medicine Annual Meeting 1995, Florida, USA. Abstract 46: 35. 6. Baker EL, R Letz, A Fidler. A computer-administered Neurobehavioural Evaluation

AGOR 28

DTIC Science & Technology

2015-11-20

unclassified c. THIS PAGE unclassified Standard Form 298 (Rev. 8-98) Prescribed by ANSI Std Z39-18 2 Exhaust Baffles • December Dry ...Docking Canceled – The floating dry dock is not certified so the docking has been canceled. Divers should do hull and prop cleaning prior to builders...operating temperature of 125-degrees F. A cooler may be necessary to correct this issue. • Uncontaminated Sea Chest – Reports from Armstrong indicate

VSF Measurements and Inversion for RaDyO

DTIC Science & Technology

2012-09-30

near-surface waters, including the surf zone. APPROACH MASCOT (Multi-Angle SCattering Optical Tool) has a 30 mW 658 nm laser diode source...in Santa Barbara Channel are provided in Fig. 1. Despite the widespread use of polarized laser sources across a diversity of Navy applications, this...operations that rely on divers, cameras, laser imaging systems, and active and passive remote sensing systems. These include mine countermeasures, harbor

Volumetric neuroimage analysis extensions for the MIPAV software package.

PubMed

Bazin, Pierre-Louis; Cuzzocreo, Jennifer L; Yassa, Michael A; Gandler, William; McAuliffe, Matthew J; Bassett, Susan S; Pham, Dzung L

2007-09-15

We describe a new collection of publicly available software tools for performing quantitative neuroimage analysis. The tools perform semi-automatic brain extraction, tissue classification, Talairach alignment, and atlas-based measurements within a user-friendly graphical environment. They are implemented as plug-ins for MIPAV, a freely available medical image processing software package from the National Institutes of Health. Because the plug-ins and MIPAV are implemented in Java, both can be utilized on nearly any operating system platform. In addition to the software plug-ins, we have also released a digital version of the Talairach atlas that can be used to perform regional volumetric analyses. Several studies are conducted applying the new tools to simulated and real neuroimaging data sets.

Nuclear reactor pressure vessel support system

DOEpatents

Sepelak, George R.

1978-01-01

A support system for nuclear reactor pressure vessels which can withstand all possible combinations of stresses caused by a postulated core disrupting accident during reactor operation. The nuclear reactor pressure vessel is provided with a flange around the upper periphery thereof, and the flange includes an annular vertical extension formed integral therewith. A support ring is positioned atop of the support ledge and the flange vertical extension, and is bolted to both members. The plug riser is secured to the flange vertical extension and to the top of a radially outwardly extension of the rotatable plug. This system eliminates one joint through which fluids contained in the vessel could escape by making the fluid flow path through the joint between the flange and the support ring follow the same path through which fluid could escape through the plug risers. In this manner, the sealing means to prohibit the escape of contained fluids through the plug risers can also prohibit the escape of contained fluid through the securing joint.

Cognitive symptoms and welding fume exposure.

PubMed

Ross, John A S; Macdiarmid, Jennifer I; Semple, Sean; Watt, Stephen J; Moir, Gill; Henderson, George

2013-01-01

Prevalence of moderate to severe cognitive symptoms is markedly higher in UK professional divers who have also worked as a welder (28%) than in either divers who have not welded (18%) or offshore workers who have worked neither as a diver nor as a welder (6%). To determine whether cognitive symptoms are related to welding fume exposure or diving. Three age-matched groups of male workers were studied using postal questionnaire: professional divers who had worked as a welder (PDW, n = 361), professional welders who had not dived (NDW, n = 352), and offshore oil field workers who had neither dived nor welded (NDNW, n =503). Health-related quality of life was assessed by the Short Form 12 questionnaire (SF12). Cognitive symptomatology was assessed using the Cognitive Failures Questionnaire (CFQ). A single variable for welding fume exposure (mg m(-3) days) was calculated, incorporating welding experience in different environments and using different welding techniques and respiratory protective equipment. The level of fume exposure during hyperbaric welding operations was measured during such work as ambient PM(10) (particles of 10 µm or less). Diving exposure was assessed as the number of dives performed plus the number of days spent working during saturation diving. Questionnaires were returned by 153 PDW, 108 NDW, and 252 NDNW. SF12 scores were the same in all groups and fell within normative values. Mean (95% CI) CFQ scores were higher in PDW [40.3 (37.7-42.9)] than in both NDW [34.6 (31.6-37.7)] and NDNW [32.1 (30.4-33.9)], but the scores in no groups fell outside the normative range. The mean PM(10) exposure during hyperbaric welding operations was 2.58 mg m(-3). The geometric mean mg m(-3) days (95% CI) for welding fume exposure in NDW [33 128 (24 625-44 567) n = 85] was higher than for that in PDW [10 904 (8103-14 673) n = 112]. For PDW the geometric mean (95% CI) diving exposure was 1491 [(1192-1866) n = 94] dives and days in saturation. In the general linear model regression analyses adjusted for age, alcohol consumption, and somatization, there was no signification association of CFQ score with either welding fume exposure (F = 0.072, P = 0.79, n = 152) or diving exposure (F = 0.042, P = 0.84, n = 74). In conclusion, cognitive sympomatology was not related to retrospectively assessed measures of welding fume exposure or diving experience. In addition, the levels of cognitive symptomatology, even in PDW, did not exceed normative values.

A comparative evaluation of two decompression procedures for technical diving using inflammatory responses: compartmental versus ratio deco.

PubMed

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.

Chest sonography detects lung water accumulation in healthy elite apnea divers.

PubMed

Frassi, Francesca; Pingitore, Alessandro; Cialoni, Danilo; Picano, Eugenio

2008-10-01

Ultrasound lung comets (ULCs) detected by chest sonography are a simple, noninvasive, semiquantitative sign of increased extravascular lung water. Pulmonary edema may occur in elite apnea divers, possibly triggered by centralization of blood flow from the periphery to pulmonary vessels. We assessed the prevalence of ULCs in top-level breath-hold divers after immersion. We evaluated 31 consecutive healthy, top-level, breath-hold divers (10 female, 21 male; age 31 +/- 5 years) participating in a yearly international apnea diving contest in Sharm-el-Sheik, Egypt, November 1 to 3, 2007. We performed chest and cardiac sonography with a transthoracic probe (2.5-3.5 MHz, Esaote Mylab) in all divers, both on the day before and 10 +/- 9 minutes after immersion. In a subset of 4 divers, chest scan was also repeated at 24 hours after immersion. ULCs were evaluated on the anterior and posterior chest at 61 predefined scanning sites. An independent sonographer, blind to both patient identity and status (pre- or post-diving), scored ULCs. Diving depth ranged from 31 to 112 m. Duration of immersion ranged from 120 to 225 seconds. The ULC score was 0.5 +/- 1.5 at baseline and 13 +/- 21 after diving (P = .012). At individual patient analysis, ULCs appeared in 14 athletes (45%) after diving. Of these 14 athletes, 4 were asymptomatic, 6 showed aspecific symptoms with transient loss of motor control ("Samba"), 2 had palpitations with frequent premature ventricular contractions, and 2 had persistent cough with hemoptysis and pulmonary crackles. In a subset of 4 athletes with post-diving ULCs in whom late follow-up study also was available, chest sonography findings fully normalized at 24 hours of follow-up. In top-level breath-hold divers, chest sonography frequently reveals an increased number of ULCs after immersion, indicating a relatively high prevalence of (often subclinical) reversible extravascular lung water accumulation.

Oxygen, the lung and the diver: friends and foes?

PubMed

van Ooij, Pieter-Jan A M; Sterk, Peter J; van Hulst, Robert A

2016-12-01

Worldwide, the number of professional and sports divers is increasing. Most of them breathe diving gases with a raised partial pressure of oxygen (P O 2 ). However, if the P O 2 is between 50 and 300 kPa (375-2250 mmHg) (hyperoxia), pathological pulmonary changes can develop, known as pulmonary oxygen toxicity (POT). Although in its acute phase, POT is reversible, it can ultimately lead to non-reversible pathological changes. Therefore, it is important to monitor these divers to prevent them from sustaining irreversible lesions.This review summarises the pulmonary pathophysiological effects when breathing oxygen with a P O 2 of 50-300 kPa (375-2250 mmHg). We describe the role and the limitations of lung function testing in monitoring the onset and development of POT, and discuss new techniques in respiratory medicine as potential markers in the early development of POT in divers. Copyright ©ERS 2016.

Flying after diving: should recommendations be reviewed? In-flight echocardiographic study in bubble-prone and bubble-resistant divers.

PubMed

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

2015-03-01

Inert gas accumulated after multiple recreational dives can generate tissue supersaturation and bubble formation when ambient pressure decreases. We hypothesized that this could happen even if divers respected the currently recommended 24-hour pre-flight surface interval (PFSI). We performed transthoracic echocardiography (TTE) on a group of 56 healthy scuba divers (39 male, 17 female) as follows: first echo--during the outgoing flight, no recent dives; second echo--before boarding the return flight, after a multiday diving week in the tropics and a 24-hour PFSI; third echo--during the return flight at 30, 60 and 90 minutes after take-off. TTE was also done after every dive during the week's diving. Divers were divided into three groups according to their 'bubble-proneness': non-bubblers, occasional bubblers and consistent bubblers. During the diving, 23 subjects never developed bubbles, 17 only occasionally and 16 subjects produced bubbles every day and after every dive. Bubbles on the return flight were observed in eight of the 56 divers (all from the 'bubblers' group). Two subjects who had the highest bubble scores during the diving were advised not to make the last dive (increasing their PFSI to approximately 36 hours), and did not demonstrate bubbles on the return flight. Even though a 24-hour PFSI is recommended on the basis of clinical trials showing a low risk of decompression sickness (DCS), the presence of venous gas bubbles in-flight in eight of 56 divers leads us to suspect that in real-life situations DCS risk after such a PFSI is not zero.

Memory and metacognition in dangerous situations: investigating cognitive impairment from gas narcosis in undersea divers.

PubMed

Hobbs, Malcolm; Higham, Philip A; Kneller, Wendy

2014-06-01

The current study tested whether undersea divers are able to accurately judge their level of memory impairment from inert gas narcosis. Inert gas narcosis causes a number of cognitive impairments, including a decrement in memory ability. Undersea divers may be unable to accurately judge their level of impairment, affecting safety and work performance. In two underwater field experiments, performance decrements on tests of memory at 33 to 42 m were compared with self-ratings of impairment and resolution. The effect of depth (shallow [I-II m] vs. deep [33-42 m]) was measured on free-recall (Experiment I; n = 41) and cued-recall (Experiment 2; n = 39) performance, a visual-analogue self-assessment rating of narcotic impairment, and the accuracy of judgements-of-learning JOLs). Both free- and cued-recall were significantly reduced in deep, compared to shallow, conditions. This decrement was accompanied by an increase in self-assessed impairment. In contrast, resolution (based on JOLs) remained unaffected by depth. The dissociation of memory accuracy and resolution, coupled with a shift in a self-assessment of impairment, indicated that divers were able to accurately judge their decrease in memory performance at depth. These findings suggest that impaired self-assessment and resolution may not actually be a symptom of narcosis in the depth range of 33 to 42 m underwater and that the divers in this study were better equipped to manage narcosis than prior literature suggested. The results are discussed in relation to implications for diver safety and work performance.

The healthy diver: A cross-sectional survey to evaluate the health status of recreational scuba diver members of Divers Alert Network (DAN).

PubMed

Ranapurwala, Shabbar I; Kucera, Kristen L; Denoble, Petar J

2018-01-01

Scuba diver fitness is paramount to confront environmental stressors of diving. However, the diving population is aging and the increasing prevalence of diseases may be a concern for diver fitness. The purpose of this study is to assess the demographics, lifestyle factors, disease prevalence, and healthcare access and utilization of Divers Alert Network (DAN) members and compare them with those from the general population. DAN membership health survey (DMHS) was administered online in 2011 to DAN members in the United States (US). Health status of DMHS respondents was compared with the general US population data from the Center for Disease Control and Prevention's Behavioral Risk Factor Surveillance System using two-sided student's t-tests and Mantel-Haenszel chi-square tests. Univariate and multivariate logistic regression analyses were conducted to identify factors associated with healthcare utilization among the DMHS participants. Compared to the general US population, the DMHS population had lower prevalence of asthma, heart attack, angina, stroke, diabetes, hypertension, hypercholesterolemia, and disabilities (p<0.01); more heavy alcohol drinkers, and fewer smokers (p<0.01); and greater access and utilization (routine checkup) of healthcare (p<0.01). Healthcare utilization in males was lower than among females. Increasing age and increase in the number of chronic illnesses were associated with increased healthcare utilization. DAN members are healthier than the general US population. DAN members also have better access to healthcare and utilize healthcare for preventive purposes more often than the general population. DAN members appear to have a better fitness level than their non-diving peers.

Dotette: Programmable, high-precision, plug-and-play droplet pipetting.

PubMed

Fan, Jinzhen; Men, Yongfan; Hao Tseng, Kuo; Ding, Yi; Ding, Yunfeng; Villarreal, Fernando; Tan, Cheemeng; Li, Baoqing; Pan, Tingrui

2018-05-01

Manual micropipettes are the most heavily used liquid handling devices in biological and chemical laboratories; however, they suffer from low precision for volumes under 1  μ l and inevitable human errors. For a manual device, the human errors introduced pose potential risks of failed experiments, inaccurate results, and financial costs. Meanwhile, low precision under 1  μ l can cause severe quantification errors and high heterogeneity of outcomes, becoming a bottleneck of reaction miniaturization for quantitative research in biochemical labs. Here, we report Dotette, a programmable, plug-and-play microfluidic pipetting device based on nanoliter liquid printing. With automated control, protocols designed on computers can be directly downloaded into Dotette, enabling programmable operation processes. Utilizing continuous nanoliter droplet dispensing, the precision of the volume control has been successfully improved from traditional 20%-50% to less than 5% in the range of 100 nl to 1000 nl. Such a highly automated, plug-and-play add-on to existing pipetting devices not only improves precise quantification in low-volume liquid handling and reduces chemical consumptions but also facilitates and automates a variety of biochemical and biological operations.

Multiphysics Object-Oriented Simulation Environment (MOOSE)

ScienceCinema

None

2017-12-09

Nuclear reactor operators can expand safety margins with more precise information about how materials behave inside operating reactors. INL's new simulation platform makes such studies easier & more informative by letting researchers "plug-n-play" their mathematical models, skipping years of computer code development.

Combustion engine variable compression ratio apparatus and method

DOEpatents

Lawrence,; Keith, E [Peoria, IL; Strawbridge, Bryan E [Dunlap, IL; Dutart, Charles H [Washington, IL

2006-06-06

An apparatus and method for varying a compression ratio of an engine having a block and a head mounted thereto. The apparatus and method includes a cylinder having a block portion and a head portion, a piston linearly movable in the block portion of the cylinder, a cylinder plug linearly movable in the head portion of the cylinder, and a valve located in the cylinder plug and operable to provide controlled fluid communication with the block portion of the cylinder.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lemonds, David Preston

A breech lock for a glove box is provided that may be used to transfer one or more items into the glove box. The breech lock can be interchangeably installed in place of a plug, glove, or other device in a port or opening of a glove box. Features are provided to aid the removal of items from the breech lock by a gloved operator. The breech lock can be reused or, if needed, can be replaced with a plug, glove, or other device at the port or opening of the glove box.

Phenytoin as a countermeasure for motion sickness in NASA maritime operations

NASA Technical Reports Server (NTRS)

Woodard, Daniel; Knox, Glenn; Myers, K. J.; Chelen, William; Ferguson, Becki

1993-01-01

Seasickness is the most prevalent form of motion sickness and is an operational problem during Space Shuttle Solid-fueled Rocket Booster (SRB) retrieval. Phenytoin has been shown to protect against motion sickness induced by Coriolis stress. We exposed SRB recovery personnel to off-vertical rotation and sea motion after phenytoin or placebo. Phenytoin blood levels of at least 9 micrograms/ml were protective against motion sickness at sea. No change in susceptibility to nitrogen narcosis was seen in divers in chamber tests at 460 KPa. Phenytoin was used during the performance of critical and hazardous tasks during training and actual SRB recovery operations. Phenytoin is an effective operational countermeasure for motion sickness for selected SRB crew members.

Questions Students Ask: How Can a Downhill Skier Move Faster than a Sky Diver?

ERIC Educational Resources Information Center

Armenti, Angelo, Jr.

1984-01-01

Discusses the relationship of gravity, coefficient of friction, surface area, and Newton's second law to explain the physics involved in downhill skiers being able to move faster than sky divers in free fall. (JM)

Incidence of Decompression Illness and Other Diving Related Medical Problems Amongst Royal Navy Divers 1995-1999

DTIC Science & Technology

1999-01-01

conditions hypobares ou hyperbares ] To order the complete compilation report, use: ADA395680 The component part is provided here to allow users access to...following report: TITLE: Operational Medical Issues in Hypo-and Hyperbaric Conditions [les Questions medicales a caractere oprationel liees aux...Navy diving accidents, and with the assistance of the British Hyperbaric Association (BHA) all civilian cases of decompression illness treated by member

A Biomedical Assessment of a One-Atmosphere Diving System: JIM-4.

DTIC Science & Technology

1981-12-01

physiological adaptation is required, work methods are based on support vehicles , which can provide recompression chambers for divers after deep diving, and on...Charles Brooner HMI Steve Hall NMRI Charles Flynn Cliff Newell Operational and Technical Support NOAA ENCM( MDV ) William W. Winters MRCS( MDV ) Charles...Submergence Rescue Vehicle (DSRV), as shown in Fig. 26. It was assumed that in the event a submarine was incapacitated at great depths, a JIM

Journal of Special Operations Medicine. Volume 7, Edition 4, Fall 2007

DTIC Science & Technology

2007-01-01

which demonstrated massive amounts of pericardial fat , but no blood (a false positive FAST). Exploratory laparatomy revealed a catastrophic supra...ARTERIAL GAS EMBOLISM An additional concern in the unconscious diver is barotrauma and arterial gas embolism (AGE). Boyle’s law states that as pressure...ment in 32 cases of air embolism (abs). Proceedings: Joint Meeting on Diving andHyperbaric Medicine, 11-18 August. Amsterdam, The Netherlands, pg. 90. 13

Marine Mammals Ashore: A Field Guide for Strandings. Second Edition

DTIC Science & Technology

2005-01-01

Cruz, CA (Ch. 9); Diana M. Antochiw-Alonzo, Red de Varamientos, Yucatan (Ch. 2, 6); James Barnett, British Divers Marine Life Rescue, London, UK (Ch...diagnosed in free-ranging ringed seals" at a time when persistent ice interfered with food production. Nutritional stress also has been implicated in...emergency treatment, nutrition , surgery, quarantine, chronic care, and raising orphaned pups. Some operations continue around the clock. It also serves as a

Force Reconnaissance: A Key Enabler in the Marine Air Ground Task Force and Beyond

DTIC Science & Technology

2012-03-13

round Task Force Advance Force Operations, Deep Reconnaissance, Military Free Fall (MFF), Marine Combatar t Diver ( MCD ), Joint Terminal Attack...Marine Division. These early years focused on developing the doctrine and insertion skills became legendary in the crucible of South East Asia , and...potential for regional powers to threaten critical U.S. interests. Areas of particular concern in the QDR are the Middle East and Asia .41 The United

'Weightless' acrylic painting by Jack Kroehnke

NASA Technical Reports Server (NTRS)

1987-01-01

'Weightless' acrylic painting by Jack Kroehnke depicts STS-26 Discovery, Orbiter Vehicle (OV) 103, Mission Specialist (MS) David C. Hilmers participating in extravehicular activity (EVA) simulation in JSC Weightless Environment Training Facility (WETF) Bldg 29. In the payload bay (PLB) mockup, Hilmers, wearing extravehicular mobility unit (EMU), holds onto the mission-peculiar equipment support structure in foreground while SCUBA-equipped diver monitors activity overhead and camera operator records EVA procedures. Copyrighted art work for use by NASA.

Diving accidents in sports divers in Orkney waters.

PubMed

Trevett, A J; Forbes, R; Rae, C K; Sheehan, C; Ross, J; Watt, S J; Stephenson, R

2001-12-01

Scapa Flow in Orkney is one of the major world centres for wreck diving. Because of the geography of Orkney and the nature of the diving, it is possible to make relatively accurate estimates of the number of dives taking place. The denominator of dive activity allows the unusual opportunity of precise calculation of accident rates. In 1999, one in every 178 sports divers visiting Orkney was involved in a significant accident, in 2000 the figure was one in 102. Some of these accidents appear to have been predictable and could be avoided by better education and preparation of visiting divers.

Heat loss and hypothermia in free diving: Estimation of survival time under water

NASA Astrophysics Data System (ADS)

Aguilella-Arzo, Marcel; Alcaraz, Antonio; Aguilella, Vicente M.

2003-04-01

The heat exchange between a diver and the colder surrounding water is analyzed on the basis of the fundamental equations of thermal transport. To estimate the decrease in the diver's body temperature as a function of time, we discuss the complex interplay of several factors including the body heat production rate, the role of the diver's wet suit, and the way different heat exchange mechanisms (conduction, convection, and radiation) contribute to thermal transport. This knowledge could be useful to prevent physiological disorders that occur when the human body temperature drops below 35 °C.

Development of a Hydrogen-Fueled Diver Heater.

DTIC Science & Technology

1982-05-01

HHV ) of 319 B/lb, and a lower heating value ( LHV ) of 270 B/lb. The difference between HHV and LHV is the energy of water con- Sdensation. For an...AO-A115 173 BATTELLE COLUSUIJA LAOS 0O4 F/0 6/17 DEVELOPMNT OF A MYDR(N- FUELED DIVER IEATER. CU) MCAY U P 5 RIEGEL M61331-81-C-00?S I 4KLASSIFIED ML... FUELED DIVER HEATER to I NAVAL COASTAL SYSTEMS CENTER May 1982 by P. S. RIEGEL Contract No. N61331-81-C-0075 it Columbus Laboratories 505 King Avenue JUNO

A day in the life of a diabetic diver: the Undersea and Hyperbaric Medical Society/Divers Alert Network protocol for diving with diabetes in action.

PubMed

Johnson, Rebecca

2016-09-01

Some people with well-managed insulin-dependent diabetes can dive safely. Those cleared to participate should control tightly the variables that impact blood glucose levels, including activity, timing, food and insulin. Honest self-assessment is critical. A diabetic diver should cancel a dive if seasick, unusually anxious, or following significant high or low blood glucose levels in the preceding 24 hours. The diver should enter the water with a blood glucose level above 8.3 mmol·L⁻¹ and below 14 mmol·L⁻¹ with a stable or rising trend in blood glucose established with glucose tests at 90, 60, and 30 minutes prior to a dive. The diver should carry emergency glucose at all times and brief dive buddies about hypoglycaemia procedures. This is a personal account of the author's experience diving with type 1 diabetes and details how the UHMS/DAN recommendations are put into practice on dive days. Key elements of the self-assessment process, long- and rapid-acting insulin adjustments, meal timing, responses to blood glucose trends, handling hypoglycaemia and approaching multi-dive days are described. Some considerations for people using insulin pumps are also briefly discussed.

A case-control study evaluating relative risk factors for decompression sickness: a research report.

PubMed

Suzuki, Naoko; Yagishita, Kazuyosi; Togawa, Seiichiro; Okazaki, Fumihiro; Shibayama, Masaharu; Yamamoto, Kazuo; Mano, Yoshihiro

2014-01-01

Factors contributing to the pathogenesis of decompression sickness (DCS) in divers have been described in many studies. However, relative importance of these factors has not been reported. In this case-control study, we compared the diving profiles of divers experiencing DCS with those of a control group. The DCS group comprised 35 recreational scuba divers who were diagnosed by physicians as having DCS. The control group consisted of 324 apparently healthy recreational divers. All divers conducted their dives from 2009 to 2011. The questionnaire consisted of 33 items about an individual's diving profile, physical condition and activities before, during and just after the dive. To simplify dive parameters, the dive site was limited to Izu Osezaki. Odds ratios and multiple logistic regression were used for the analysis. Odds ratios revealed several items as dive and health factors associated with DCS. The major items were as follows: shortness of breath after heavy exercise during the dive (OR = 12.12), dehydration (OR = 10.63), and maximum dive depth > 30 msw (OR = 7.18). Results of logistic regression were similar to those by odds ratio analysis. We assessed the relative weights of the surveyed dive and health factors associated with DCS. Because results of several factors conflict with previous studies, future studies are needed.

Better Building Alliance, Plug and Process Loads in Commercial Buildings: Capacity and Power Requirement Analysis (Brochure)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

2014-09-01

This brochure addresses gaps in actionable knowledge that can help reduce the plug load capacities designed into buildings. Prospective building occupants and real estate brokers lack accurate references for plug and process load (PPL) capacity requirements, so they often request 5-10 W/ft2 in their lease agreements. This brochure should be used to make these decisions so systems can operate more energy efficiently; upfront capital costs will also decrease. This information can also be used to drive changes in negotiations about PPL energy demands. It should enable brokers and tenants to agree about lower PPL capacities. Owner-occupied buildings will also benefit.more » Overestimating PPL capacity leads designers to oversize electrical infrastructure and cooling systems.« less

43 CFR 3162.3-4 - Well abandonment.

Code of Federal Regulations, 2011 CFR

2011-10-01

... 43 Public Lands: Interior 2 2011-10-01 2011-10-01 false Well abandonment. 3162.3-4 Section 3162.3... Operating Rights Owners and Operators § 3162.3-4 Well abandonment. (a) The operator shall promptly plug and... newly completed or recompleted well in which oil or gas is not encountered in paying quantities or which...

43 CFR 3162.3-4 - Well abandonment.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 43 Public Lands: Interior 2 2012-10-01 2012-10-01 false Well abandonment. 3162.3-4 Section 3162.3... Operating Rights Owners and Operators § 3162.3-4 Well abandonment. (a) The operator shall promptly plug and... newly completed or recompleted well in which oil or gas is not encountered in paying quantities or which...

43 CFR 3162.3-4 - Well abandonment.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 43 Public Lands: Interior 2 2014-10-01 2014-10-01 false Well abandonment. 3162.3-4 Section 3162.3... Operating Rights Owners and Operators § 3162.3-4 Well abandonment. (a) The operator shall promptly plug and... newly completed or recompleted well in which oil or gas is not encountered in paying quantities or which...

43 CFR 3162.3-4 - Well abandonment.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 43 Public Lands: Interior 2 2013-10-01 2013-10-01 false Well abandonment. 3162.3-4 Section 3162.3... Operating Rights Owners and Operators § 3162.3-4 Well abandonment. (a) The operator shall promptly plug and... newly completed or recompleted well in which oil or gas is not encountered in paying quantities or which...

Orion Neutral Buoyancy Lab (NBL) Activities

NASA Image and Video Library

2016-09-20

Tim Goddard, NASA Open Water Recovery Operations director, briefs U.S. Navy divers, Air Force pararescuemen and Coast Guard rescue swimmers during training in the Neutral Buoyancy Laboratory at NASA’s Johnson Space Center in Houston. The group is preparing to practice Orion underway recovery techniques using a test version of the Orion spacecraft. Training will help the team prepare for Underway Recovery Test 5 for Exploration Mission 1 aboard the USS San Diego in the Pacific Ocean off the coast of California in October. The Ground Systems Development and Operations Program, along with the U.S. Navy and Lockheed Martin, are preparing the recovery team, hardware and operations to support EM-1 recovery.

Orion's Neutral Buoyancy Lab (NBL) Activities

NASA Image and Video Library

2016-09-21

Tim Goddard, center, NASA Open Water Recovery Operations director, reviews recovery procedures with U.S. Navy divers, Air Force pararescuemen and Coast Guard rescue swimmers during training in the Neutral Buoyancy Laboratory at NASA’s Johnson Space Center in Houston. The group is practicing Orion underway recovery techniques using a test version of the Orion spacecraft. Training will help the team prepare for Underway Recovery Test 5 for Exploration Mission 1 aboard the USS San Diego in the Pacific Ocean off the coast of California in October. The Ground Systems Development and Operations Program, along with the U.S. Navy and Lockheed Martin, are preparing the recovery team, hardware and operations to support EM-1 recovery.

Orion Neutral Buoyancy Lab (NBL) Activities

NASA Image and Video Library

2016-09-20

Tim Goddard, far right, NASA Open Water Recovery Operations director, briefs U.S. Navy divers, Air Force pararescuemen and Coast Guard rescue swimmers during training in the Neutral Buoyancy Laboratory at NASA’s Johnson Space Center in Houston. The group is preparing to practice Orion underway recovery techniques using a test version of the Orion spacecraft. Training will help the team prepare for Underway Recovery Test 5 for Exploration Mission 1 aboard the USS San Diego in the Pacific Ocean off the coast of California in October. The Ground Systems Development and Operations Program, along with the U.S. Navy and Lockheed Martin, are preparing the recovery team, hardware and operations to support EM-1 recovery.

Performance of life support breathing apparatus for under-ice diving operations.

PubMed

Lang, Michael A; Clarke, John R

2017-01-01

Single-hose scuba regulators dived in very cold water may suffer first- or second-stage malfunction, yielding complete occlusion of air flow or massive freeflow that rapidly expends a diver's air supply. This study, conducted in Antarctica, evaluated the under-ice performance of a sampling of commercially available regulators. Seventeen science divers logged a total of 305 dives in -1.86°C seawater under 6-meter-thick Antarctic fast-ice over two field seasons in 2008 and 2009. Dive profiles had an average depth of 30 msw and dive time of 29 minutes, including a mandatory three-minute safety stop at 6 msw. Sixty-nine unmodified regulator units (17 models) from 12 different manufacturers underwent standardized pre-dive regulator care and were randomly assigned to divers. Depths and times of onset of second-stage regulator freeflow were recorded. In 305 dives, there were 65 freeflows. The freeflows were not evenly distributed across the regulator brands. Regulator failure rates fell into two categories (⟨ 11% and ⟩ 26%). The regulators classified for the purpose of the test as "acceptable" (⟨ 11% failure rate: Dive-Rite Jetstream, Sherwood Maximus SRB3600, Poseidon Xstream Deep, Poseidon Jetstream, Sherwood Maximus SRB7600, Poseidon Cyklon, Mares USN22 Abyss) experienced only nine freeflows out of 146 exposures for a 6% overall freeflow incidence. Those classified as "unacceptable" (⟨ 26% failure rate) suffered 56 freeflows out of 159 exposures (35% freeflow incidence.). Contrary to expectations, the pooled incidences for the seven best performing regulators was significantly different by Chi-square test from the 10 remaining regulators (P ⟨ 0.001).

A novel model of acellular dermal matrix plug for anal fistula treatment. Report of a case and surgical consideration based on first utility in Poland.

PubMed

Bobkiewicz, Adam; Krokowicz, Łukasz; Borejsza-Wysocki, Maciej; Banasiewicz, Tomasz

2017-08-31

Anal fistula (AF) is a pathological connection between anus and skin in its surroundings. The main reason for the formation of anal fistula is a bacterial infection of the glands within the anal crypts. One of the modern techniques for the treatment of fistulas that do not interfere with the sphincters consists in implantation of a plug made from collagen material. We are presenting the first Polish experience with a new model of biomaterial plug for the treatment of anal fistula. We also point out key elements of the procedure (both preoperative and intraoperative) associated with this method. In the authors' opinion, the method is simple, safe and reproducible. Innovative shape of the plug minimizes the risk of its migration and rotation. It also perfectly blends with and adapts to the course and shape of the fistula canal, allowing it to become incorporated and overgrown with tissue in the fistula canal. The relatively short operation time, minor postoperative pain and faster convalescence are with no doubt additional advantages of the method. Long-term observation involving more patients is essential for evaluation of the efficacy of the treatment of fistulas with the new type of plug.

Do reef fish habituate to diver presence? Evidence from two reef sites with contrasting historical levels of SCUBA intensity in the Bay Islands, Honduras.

PubMed

Titus, Benjamin M; Daly, Marymegan; Exton, Dan A

2015-01-01

Contact between humans and the marine environment is increasing, but the capacity of communities to adapt to human presence remains largely unknown. The popularization of SCUBA diving has added a new dimension to human impacts in aquatic systems and, although individual-level impacts have been identified, cumulative effects on ecosystem function and community-wide responses are unclear. In principle, habituation may mitigate the consequences of human presence on the biology of an individual and allow the quick resumption of its ecological roles, but this has not been documented in aquatic systems. Here, we investigate the short-term impact of human presence and the long-term habituation potential of reef-fish communities to recreational SCUBA divers by studying symbiotic cleaning interactions on coral reefs with differing levels of historical contact with divers. We show that incidences of human contact result in a smaller decline in ecosystem function and more rapid resumption of baseline services on a reef in Utila, Honduras that has heavy historical levels of SCUBA diver presence, compared to an un-dived reef site in the Cayos Cochinos Marine Protected Area (CCMPA). Nonetheless, despite the generally smaller change in ecosystem function and decades of regular contact with divers, cleaning behavior is suppressed by >50% at Utila when divers are present. We hypothesize that community-wide habituation of reef fish is not fully achievable and may be biologically restricted to only partial habituation. Differential responses to human presence impacts the interpretation and execution of behavioral research where SCUBA is the predominant means of data collection, and provides an important rationale for future research investigating the interplay between human presence, ecosystem function, and community structure on coral reefs.

The healthy diver: A cross-sectional survey to evaluate the health status of recreational scuba diver members of Divers Alert Network (DAN)

PubMed Central

Kucera, Kristen L.; Denoble, Petar J.

2018-01-01

Background Scuba diver fitness is paramount to confront environmental stressors of diving. However, the diving population is aging and the increasing prevalence of diseases may be a concern for diver fitness. Purpose The purpose of this study is to assess the demographics, lifestyle factors, disease prevalence, and healthcare access and utilization of Divers Alert Network (DAN) members and compare them with those from the general population. Methods DAN membership health survey (DMHS) was administered online in 2011 to DAN members in the United States (US). Health status of DMHS respondents was compared with the general US population data from the Center for Disease Control and Prevention’s Behavioral Risk Factor Surveillance System using two-sided student’s t-tests and Mantel-Haenszel chi-square tests. Univariate and multivariate logistic regression analyses were conducted to identify factors associated with healthcare utilization among the DMHS participants. Results Compared to the general US population, the DMHS population had lower prevalence of asthma, heart attack, angina, stroke, diabetes, hypertension, hypercholesterolemia, and disabilities (p<0.01); more heavy alcohol drinkers, and fewer smokers (p<0.01); and greater access and utilization (routine checkup) of healthcare (p<0.01). Healthcare utilization in males was lower than among females. Increasing age and increase in the number of chronic illnesses were associated with increased healthcare utilization. Conclusions DAN members are healthier than the general US population. DAN members also have better access to healthcare and utilize healthcare for preventive purposes more often than the general population. DAN members appear to have a better fitness level than their non-diving peers. PMID:29566018

Improved pulmonary function in working divers breathing nitrox at shallow depths

NASA Technical Reports Server (NTRS)

Fitzpatrick, Daniel T.; Conkin, Johnny

2003-01-01

INTRODUCTION: There is limited data about the long-term pulmonary effects of nitrox use in divers at shallow depths. This study examined changes in pulmonary function in a cohort of working divers breathing a 46% oxygen enriched mixture while diving at depths less than 12 m. METHODS: A total of 43 working divers from the Neutral Buoyancy Laboratory (NBL), NASA-Johnson Space Center completed a questionnaire providing information on diving history prior to NBL employment, diving history outside the NBL since employment, and smoking history. Cumulative dive hours were obtained from the NBL dive-time database. Medical records were reviewed to obtain the diver's height, weight, and pulmonary function measurements from initial pre-dive, first year and third year annual medical examinations. RESULTS: The initial forced vital capacity (FVC) and forced expiratory volume in 1 s (FEV1) were greater than predicted, 104% and 102%, respectively. After 3 yr of diving at the NBL, both the FVC and FEV1 showed a significant (p < 0.01) increase of 6.3% and 5.5%, respectively. There were no significant changes in peak expiratory flow (PEF), forced mid-expiratory flow rate (FEF(25-75%)), and forced expiratory flow rates at 25%, 50%, and 75% of FVC expired (FEF25%, FEF50%, FEF75%). Cumulative NBL dive hours was the only contributing variable found to be significantly associated with both FVC and FEV1 at 1 and 3 yr. CONCLUSIONS: NBL divers initially belong to a select group with larger than predicted lung volumes. Regular diving with nitrox at shallow depths over a 3-yr period did not impair pulmonary function. Improvements in FVC and FEV1 were primarily due to a training effect.

Method To Display Data On A Face Mask

NASA Technical Reports Server (NTRS)

Moore, Kevin-Duron

1995-01-01

Proposed electronic instrument displays information on diver's or firefighter's face mask. Includes mask, prism, electronic readouts, transceiver and control electronics. Mounted at periphery of diver's field of view to provide data on elapsed time, depth, pressure, and temperature. Provides greater safety and convenience to user.

46 CFR 197.204 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-10-01

... the diver access to the surrounding environment, and is capable of being used as a refuge during... supervisor. Diver means a person working beneath the surface, exposed to hyperbaric conditions, and using.... Injurious corrosion means an advanced state of corrosion which may impair the structural integrity or safe...

Severe capillary leak syndrome after inner ear decompression sickness in a recreational scuba diver.

PubMed

Gempp, Emmanuel; Lacroix, Guillaume; Cournac, Jean-Marie; Louge, Pierre

2013-07-01

Post-decompression shock with plasma volume deficit is a very rare event that has been observed under extreme conditions of hypobaric and hyperbaric exposure in aviators and professional divers. We report a case of severe hypovolemic shock due to extravasation of plasma in a recreational scuba diver presenting with inner ear decompression sickness. Impaired endothelial function can lead to capillary leak with hemoconcentration and hypotension in severe cases. This report suggests that decompression-induced circulating bubbles may have triggered the endothelial damage, activating the classic inflammatory pathway of increased vascular permeability. This observation highlights the need for an accurate diagnosis of this potentially life-threatening condition at the initial presentation in the Emergency Department after a diving-related injury. An elevated hematocrit in a diver should raise the suspicion for the potential development of capillary leak syndrome requiring specific treatment using albumin infusion as primary fluid replacement. Copyright © 2013 Elsevier Inc. All rights reserved.

An overview of changes in pressure values of the middle ear using impedance audiometry among diver candidates in a hyperbaric chamber before and after a pressure test

NASA Astrophysics Data System (ADS)

Anoraga, J. S.; Bramantyo, B.; Bardosono, S.; Simanungkalit, S. H.; Basiruddin, J.

2017-08-01

Impedance audiometry is not yet routinely used in pressure tests, especially in Indonesia. Direct exposure to pressure in a hyperbaric chamber is sometimes without any assessment of the middle ear or the Eustachian tube function (ETF) of ventilation. Impedance audiometry examinations are important to assess ETF ventilation. This study determined the middle ear pressure value changes associated with the ETF (ventilation) of prospective divers. This study included 29 prospective divers aged 20-40 years without conductive hearing loss. All subjects underwent a modified diving impedance audiometry examination both before and after the pressure test in a double-lock hyperbaric chamber. Using the Toynbee maneuver, the values obtained for changes of pressure in the middle ear were significant before and after the pressure test in the right and left ears: p < 0.001 and p = 0.018, respectively. The impedance audiometry examination is necessary for the selection of candidate divers undergoing pressure tests within a hyperbaric chamber.

Exposure to enteroviruses and hepatitis A virus among divers in environmental waters in France, first biological and serological survey of a controlled cohort.

PubMed Central

Garin, D.; Fuchs, F.; Crance, J. M.; Rouby, Y.; Chapalain, J. C.; Lamarque, D.; Gounot, A. M.; Aymard, M.

1994-01-01

An epidemiological study of hepatitis A and enteroviruses was conducted in a military diving training school, by evaluating the viral contamination of water using an ultrafiltration concentration technique, and assessing seroconversion and the presence of virus in stool specimens obtained from 109 divers and 48 controls. Three of 29 water specimens were positive for enterovirus by cell culture and 9 by molecular hybridization. There was little or no risk of virus infection during the training course (49 h exposure) because there was no significant difference between divers and controls for both viral isolation and seroconversion. However, a higher percentage of coxsackievirus B4 and B5 seropositive divers suggests that these were more exposed during previous water training. No hepatitis A virus (HAV) detection and no seroconversion to HAV was observed. The rate of HAV seropositive subjects was 17% in this 24.5-year-old population. PMID:7995363

Cancer risks in naval divers with multiple exposures to carcinogens.

PubMed Central

Richter, Elihu D; Friedman, Lee S; Tamir, Yuval; Berman, Tamar; Levy, Or; Westin, Jerome B; Peretz, Tamar

2003-01-01

We investigated risks for cancer and the case for a cause-effect relationship in five successive cohorts of naval commando divers (n = 682) with prolonged underwater exposures (skin, gastrointestinal tract, and airways) to many toxic compounds in the Kishon River, Israel's most polluted waterway, from 1948 to 1995. Releases of industrial, ship, and agricultural effluents in the river increased substantially, fish yields decreased, and toxic damage to marine organisms increased. Among the divers (16,343 person-years follow-up from 18 years of age to year 2000), the observed/expected ratio for all tumors was 2.29 (p<0.01). Risks increased in cohorts first diving after 1960 compared to risks in earlier cohorts, notably for hematolymphopoietic, central nervous system, gastrointestinal, and skin cancer; induction periods were often brief. The findings suggest that the increases in risk for cancer and short induction periods resulted from direct contact with and absorption of multiple toxic compounds. Early toxic effects in marine life predicted later risks for cancer in divers. PMID:12676624

Change of occurance of type 1 and type 2 decompression sickness of divers treated at the Croatian Naval Medical Institute in the period from 1967 to 2000.

PubMed

Andrić, Dejan; Petri, Nadan M; Stipancević, Hrvoje; Petri, Lena Vranjković; Kovacević, Hasan

2003-01-01

A significant change of occurrence (p=0.0343) of type 1 and type 2 decompression sickness (DCS) of divers in Croatia was observed in the period from 1991 to 2002 (type 1: n=26, 37.68% and type 2: n=43, 62.32%) compared with the period from 1967 to 1990 (type 1: n=93, 52.84% and type 2: n=83, 47.16%). The change was attributed to the extensive usage of diving computers and artificial gas mixtures which enable extended bottom times and deeper dives, thus putting divers at an increased decompression risk. The importance of the results of this report is in the fact that permanent neurological deficit occurs only after type 2 DCS. Injured divers with permanent loss after type 2 DCS are not fit for diving and require a long term medical care, thus becoming a significant public health problem.

Decompression illness secondary to occupational diving: recommended management based current legistation and practice in Malaysia.

PubMed

Rozali, A; Khairuddin, H; Sherina, M S; Zin, B Mohd; Sulaiman, A

2008-06-01

Occupational divers are exposed to hazards which contribute to the risk of developing decompression illnesses (DCI). DCI consists of Type I decompression sickness (DCS), Type II DCS and arterial gas embolism (AGE), developed from formation of bubbles in the tissues or circulation as a result of inadequate elimination of inert gas (nitrogen) after a dive. In Malaysia, DCI is one of the significant contributions to mortality and permanent residual morbidity in diving accidents. This is a case of a diver who suffered from Type II DCS with neurological complications due to an occupational diving activity. This article mentions the clinical management of the case and makes several recommendations based on current legislations and practise implemented in Malaysia in order to educate medical and health practitioners on the current management of DCI from the occupational perspective. By following these recommendations, hopefully diving accidents mainly DCI and its sequalae among occupational divers can be minimized and prevented, while divers who become injured receive the proper compensation for their disabilities.

Integrating plug-in electric vehicles into the electric power system

NASA Astrophysics Data System (ADS)

Wu, Di

This dissertation contributes to our understanding of how plug-in hybrid electric vehicles (PHEVs) and plug-in battery-only electric vehicles (EVs)---collectively termed plug-in electric vehicles (PEVs)---could be successfully integrated with the electric power system. The research addresses issues at a diverse range of levels pertaining to light-duty vehicles, which account for the majority of highway vehicle miles traveled, energy consumed by highway travel modes, and carbon dioxide emissions from on-road sources. Specifically, the following topics are investigated: (i) On-board power electronics topologies for bidirectional vehicle-to-grid and grid-to-vehicle power transfer; (ii) The estimation of the electric energy and power consumption by fleets of light-duty PEVs; (iii) An operating framework for the scheduling and dispatch of electric power by PEV aggregators; (iv) The pricing of electricity by PHEV aggregators and how it affects the decision-making process of a cost-conscious PHEV owner; (v) The impacts on distribution systems from PEVs under aggregator control; (vi) The modeling of light-duty PEVs for long-term energy and transportation planning at a national scale.

Multi-Day Air Saturation at 20 and 22 FSW With Direct Ascent: Data Report on Project 92-09

DTIC Science & Technology

2002-03-01

0802 0 air L/S; Divers 7, 8, 9, 10, 11, 12 0803 22 air R/B Feb 09 1919 22 air DMO entry, Diver 12 has scratchy throat and post-nasal drip, given aspirin...10,11, fsw 12 _ Galley is shipshape as is food. 1919 8 OK Robinson 12 describes scratchy throat & post nasal drip with ????? with purulent nasal...Ball 12 scratchy throat , sniffles, ASA 2 PO every 4 hrs 9 no c/o 7 no c/o 10 no c/o 11 mild congestion, Sudafed 60 mg Divers in good spirits 1250 8

Possible behavioural, energetic and demographic effects of displacement of red-throated divers

USGS Publications Warehouse

Dierschke, Volker; Furness, Robert W.; Gray, Carrie E.; Petersen, Ib Krag; Schmutz, Joel A.; Zydelis, Ramunas; Daunt, Francis

2017-01-01

This report comprises the main points of discussion and agreement during a workshop, held in Edinburgh in May 2017, to discuss how displacement might affect individuals and the Red-throated diver population; with additional information added by the scientists following the workshop.

76 FR 4529 - Safety Zone; Underwater Hazard, Gravesend Bay, Brooklyn, NY

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-26

... divers, U.S. Navy Explosive Ordnance Disposal divers from Naval Weapons Station Earle conducted... Government and Indian tribes. Energy Effects We have analyzed this rule under Executive Order 13211, Actions Concerning Regulations That Significantly Affect Energy Supply, Distribution, or Use. We have determined that...

Orion Underway Recovery Test 5 (URT-5)

NASA Image and Video Library

2016-10-28

U.S. Navy divers and other personnel in a rigid hull inflatable boat are handling tether lines attached to a test version of the Orion crew module during Underway Recovery Test 5 in the Pacific Ocean off the coast of California. U.S. Navy divers in a smaller watercraft called a Zodiac boat are farther away. NASA's Ground Systems Development and Operations Program and the U.S. Navy are conducting a series of tests using the well deck of the USS San Diego, several watercraft and personnel to prepare for recovery of Orion on its return from deep space missions. The testing will allow the team to demonstrate and evaluate recovery processes, procedures, hardware and personnel in open waters. Orion is the exploration spacecraft designed to carry astronauts to destinations not yet explored by humans, including an asteroid and NASA's Journey to Mars. It will have emergency abort capability, sustain the crew during space travel and provide safe re-entry from deep space return velocities. Orion is scheduled to launch on NASA's Space Launch System in late 2018. For more information, visit http://www.nasa.gov/orion.

Interim Air Purity Guidelines for Dry Deck Shelter (DDS) Operations

DTIC Science & Technology

1990-10-01

The acceptable limits for gaseous contaminants in submarine compressed air for use as diver’s breathing air are derived from the 8-hour Time Weighted...accompanying documentation. Cylinders must be declared as hazardous cargo (" Air , Compressed Non-Flammable Gas") prior to air transport. Analysis of cylinder...capi NAVAL MEDICAL RESEARCH INSTITUTE Bethesda, MD 20889-5055 NMRI 90-109 October 1990 AD-A231 432 INTERIM AIR PURITY GUIDELINES FOR DRY DECK

[Professional divers: analysis of critical issues and proposal of a health protocol for work fitness].

PubMed

Pedata, Paola; Corvino, Anna Rita; Napolitano, Raffaele Carmine; Garzillo, Elpidio Maria; Furfaro, Ciro; Lamberti, Monica

2016-01-20

From many years now, thanks to the development of modern diving techniques, there has been a rapid spread of diving activities everywhere. In fact, divers are ever more numerous both among the Armed Forces and civilians who dive for work, like fishing, biological research and archeology. The aim of the study was to propose a health protocol for work fitness of professional divers keeping in mind the peculiar work activity, existing Italian legislation that is almost out of date and the technical and scientific evolution in this occupational field. We performed an analysis of the most frequently occurring diseases among professional divers and of the clinical investigation and imaging techniques used for work fitness assessment of professional divers. From analysis of the health protocol recommended by D.M. 13 January 1979 (Ministerial Decree), that is most used by occupational health physician, several critical issues emerged. Very often the clinical investigation and imaging techniques still used are almost obsolete, ignoring the execution of simple and inexpensive investigations that are more useful for work fitness assessment. Considering the out-dated legislation concerning diving disciplines, it is necessary to draw up a common health protocol that takes into account clinical and scientific knowledge and skills acquired in this area. This protocol's aim is to propose a useful tool for occupational health physicians who work in this sector.

Dynamic Cerebral Autoregulation Is Acutely Impaired during Maximal Apnoea in Trained Divers

PubMed Central

Cross, Troy J.; Kavanagh, Justin J.; Breskovic, Toni; Johnson, Bruce D.; Dujic, Zeljko

2014-01-01

Aims To examine whether dynamic cerebral autoregulation is acutely impaired during maximal voluntary apnoea in trained divers. Methods Mean arterial pressure (MAP), cerebral blood flow-velocity (CBFV) and end-tidal partial pressures of O2 and CO2 (PETO2 and PETCO2) were measured in eleven trained, male apnoea divers (28±2 yr; 182±2 cm, 76±7 kg) during maximal “dry” breath holding. Dynamic cerebral autoregulation was assessed by determining the strength of phase synchronisation between MAP and CBFV during maximal apnoea. Results The strength of phase synchronisation between MAP and CBFV increased from rest until the end of maximal voluntary apnoea (P<0.05), suggesting that dynamic cerebral autoregulation had weakened by the apnoea breakpoint. The magnitude of impairment in dynamic cerebral autoregulation was strongly, and positively related to the rise in PETCO2 observed during maximal breath holding (R 2 = 0.67, P<0.05). Interestingly, the impairment in dynamic cerebral autoregulation was not related to the fall in PETO2 induced by apnoea (R 2 = 0.01, P = 0.75). Conclusions This study is the first to report that dynamic cerebral autoregulation is acutely impaired in trained divers performing maximal voluntary apnoea. Furthermore, our data suggest that the impaired autoregulatory response is related to the change in PETCO2, but not PETO2, during maximal apnoea in trained divers. PMID:24498340

43 CFR 3253.11 - Must I notify BLM when I have completed my exploration operations?

Code of Federal Regulations, 2011 CFR

2011-10-01

... (Continued) BUREAU OF LAND MANAGEMENT, DEPARTMENT OF THE INTERIOR MINERALS MANAGEMENT (3000) GEOTHERMAL...) Complete any geophysical exploration operations; (b) Complete the drilling of temperature gradient well(s... gradient well; and (d) Plug shot holes and reclaim all exploration sites. ...

43 CFR 3931.20 - Reclamation.

Code of Federal Regulations, 2012 CFR

2012-10-01

..., must be closed to the BLM's satisfaction. For in situ operations, all drilled holes must be plugged and...) The operator or lessee must substantially fill in, fence, protect, or close all surface openings... areas must be maintained in a secure condition during the term of the lease or exploration license...

43 CFR 3931.20 - Reclamation.

Code of Federal Regulations, 2013 CFR

2013-10-01

..., must be closed to the BLM's satisfaction. For in situ operations, all drilled holes must be plugged and...) The operator or lessee must substantially fill in, fence, protect, or close all surface openings... areas must be maintained in a secure condition during the term of the lease or exploration license...

43 CFR 3931.20 - Reclamation.

Code of Federal Regulations, 2014 CFR

2014-10-01

..., must be closed to the BLM's satisfaction. For in situ operations, all drilled holes must be plugged and...) The operator or lessee must substantially fill in, fence, protect, or close all surface openings... areas must be maintained in a secure condition during the term of the lease or exploration license...

43 CFR 3931.20 - Reclamation.

Code of Federal Regulations, 2011 CFR

2011-10-01

..., must be closed to the BLM's satisfaction. For in situ operations, all drilled holes must be plugged and...) The operator or lessee must substantially fill in, fence, protect, or close all surface openings... areas must be maintained in a secure condition during the term of the lease or exploration license...

Low current extended duration spark ignition system

DOEpatents

Waters, Stephen Howard; Chan, Anthony Kok-Fai

2005-08-30

A system for firing a spark plug is disclosed. The system includes a timing controller configured to send a first timing signal and a second timing signal. The system also includes an ignition transformer having a primary winding and a secondary winding and a spark-plug that is operably associated with the secondary winding. A first switching element is disposed between the timing controller and the primary winding of the ignition transformer. The first switching element controls a supply of power to the primary winding based on the first timing signal. Also, a second switching element is disposed between the timing controller and the primary winding of the ignition transformer. The second switching element controls the supply of power to the primary winding based on the second timing signal. A method for firing a spark plug is also disclosed.

Experimental Study of Ignition by Hot Spot in Internal Combustion Engines

NASA Technical Reports Server (NTRS)

Serruys, Max

1938-01-01

In order to carry out the contemplated study, it was first necessary to provide hot spots in the combustion chamber, which could be measured and whose temperature could be changed. It seemed difficult to realize both conditions working solely on the temperature of the cooling water in a way so as to produce hot spots on the cylinder wall capable of provoking autoignition. Moreover, in the majority of practical cases, autoignition is produced by the spark plug, one of the least cooled parts in the engine. The first procedure therefore did not resemble that which most generally occurs in actual engine operation. All of these considerations caused us to reproduce similar hot spots at the spark plugs. The hot spots produced were of two kinds and designated with the name of thermo-electric spark plug and of metallic hot spot.

ITER Port Interspace Pressure Calculations

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carbajo, Juan J; Van Hove, Walter A

The ITER Vacuum Vessel (VV) is equipped with 54 access ports. Each of these ports has an opening in the bioshield that communicates with a dedicated port cell. During Tokamak operation, the bioshield opening must be closed with a concrete plug to shield the radiation coming from the plasma. This port plug separates the port cell into a Port Interspace (between VV closure lid and Port Plug) on the inner side and the Port Cell on the outer side. This paper presents calculations of pressures and temperatures in the ITER (Ref. 1) Port Interspace after a double-ended guillotine break (DEGB)more » of a pipe of the Tokamak Cooling Water System (TCWS) with high temperature water. It is assumed that this DEGB occurs during the worst possible conditions, which are during water baking operation, with water at a temperature of 523 K (250 C) and at a pressure of 4.4 MPa. These conditions are more severe than during normal Tokamak operation, with the water at 398 K (125 C) and 2 MPa. Two computer codes are employed in these calculations: RELAP5-3D Version 4.2.1 (Ref. 2) to calculate the blowdown releases from the pipe break, and MELCOR, Version 1.8.6 (Ref. 3) to calculate the pressures and temperatures in the Port Interspace. A sensitivity study has been performed to optimize some flow areas.« less

Hydrogen-fueled diesel engine without timed ignition

NASA Technical Reports Server (NTRS)

Homan, H. S.; De Boer, P. C. T.; Mclean, W. J.; Reynolds, R. K.

1979-01-01

Experiments were carried out to investigate the feasibility of converting a diesel engine to hydrogen-fueled operation without providing a timed ignition system. Use was made of a glow plug and a multiple-strike spark plug. The glow plug was found to provide reliable ignition and smooth engine operation. It caused the hydrogen to ignite almost immediately upon the start of injection. Indicated mean effective pressures were on the order of 1.3 MPa for equivalence ratios between 0.1 and 0.4 at a compression ratio of 18. This is significantly higher than the corresponding result obtained with diesel oil (about 0.6 MPa for equivalence ratios between 0.3 and 0.9). Indicated thermal efficiencies were on the order of 0.4 for hydrogen and 0.20-0.25 for diesel oil. Operation with the multiple-strike spark system yielded similar values for IMEP and efficiency, but gave rise to large cycle-to-cycle variations in the delay between the beginning of injection and ignition. Large ignition delays were associated with large amplitude pressure waves in the combustion chamber. The measured NO(x) concentrations in the exhaust gas were of the order of 50-100 ppm. This is significantly higher than the corresponding results obtained with premixed hydrogen and air at low equivalence ratios. Compression ignition could not be achieved even at a compression ratio of 29.

AVTA Federal Fleet PEV Readiness Data Logging and Characterization Study for Department of Veterans Affairs – VA Manhattan Campus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stephen Schey; Jim Francfort

2014-10-01

This report focuses on the Department of Veterans Affairs, VA Manhattan Campus (VA- Manhattan) fleet to identify the daily operational characteristics of select vehicles and report findings on vehicle and mission characterizations to support successful introduction of plug-in electric vehicles (PEVs) into the agency’s fleet. Individual observations of these selected vehicles provide the basis for recommendations related to electric vehicle adoption and whether a battery electric vehicle or plug-in hybrid electric vehicle (collectively called PEVs) can fulfill the mission requirements.

Recording Rapidly Changing Cylinder-wall Temperatures

NASA Technical Reports Server (NTRS)

Meier, Adolph

1942-01-01

The present report deals with the design and testing of a measuring plug suggested by H. Pfriem for recording quasi-stationary cylinder wall temperatures. The new device is a resistance thermometer, the temperature-susceptible part of which consists of a gold coating applied by evaporation under high vacuum and electrolytically strengthened. After overcoming initial difficulties, calibration of plugs up to and beyond 400 degrees C was possible. The measurements were made on high-speed internal combustion engines. The increasing effect of carbon deposit at the wall surface with increasing operating period is indicated by means of charts.

30 CFR 250.1742 - What other methods can I use to verify that a site is clear?

Code of Federal Regulations, 2010 CFR

2010-07-01

...— And you must— (a) Sonar cover 100 percent of the appropriate grid area listed in § 250.1741(a) Use a sonar signal with a frequency of at least 500 kHz. (b) A diver ensure that the diver visually inspects...

PHYSIOLOGICAL EVALUATION OF A FREE-FLOODING DIVER HEAT REPLACEMENT GARMENT.

DTIC Science & Technology

The general capabilities of a free-flooding heat replacement garment in maintaining thermal comfort in 40F water, at both surface and deep diving...recorded. Suit inlet temperatures which produce a subjective response of thermal comfort by the diver (Comfort Zone Inlet Temperature) at various flow

Vapor Cartesian Diver

ERIC Educational Resources Information Center

Grebenev, Igor V.; Lebedeva, Olga V.; Polushkina, Svetlana V.

2018-01-01

The article proposes a new research object for a general physics course--the vapour Cartesian diver, designed to study the properties of saturated water vapour. Physics education puts great importance on the study of the saturated vapour state, as it is related to many fundamental laws and theories. For example, the temperature dependence of the…

Consequences of U.S. Navy Diving Mishaps: Air Embolism and Barotrauma.

DTIC Science & Technology

1985-12-01

diver), displacement of the intervertebral disc (I diver), and various combinations of hearing impairment, otitis ", media , otitis externa, and other...hospitalization for otitis media , otitis externa, and other diseases of the ear and mastoid process (8 days later)/ released from active duty (2 yrs, 4

46 CFR 115.650 - Alternative Hull Examination (AHE) Program options: Divers or underwater ROV.

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Alternative Hull Examination (AHE) Program options... MORE THAN 49 PASSENGERS INSPECTION AND CERTIFICATION Hull and Tailshaft Examinations § 115.650 Alternative Hull Examination (AHE) Program options: Divers or underwater ROV. To complete your underwater...

Finding Environmental Knowledge in SCUBA-Based Textual Materials

ERIC Educational Resources Information Center

Gündogdu, Cemal; Aygün, Yalin; Ilkim, Mehmet

2018-01-01

As marine environments within the adventure domain are future key-settings for recreational SCUBA diving experience, SCUBA-based textual materials should provide insight into environmental knowledge that is well connected to the novice divers' behaviour and attitude. This research is concerned with a major recreational SCUBA diver manual for…

Orion's Neutral Buoyancy Lab (NBL) Activities

NASA Image and Video Library

2016-09-21

U.S. Navy divers, Air Force pararescuemen and Coast Guard rescue swimmers practice Orion recovery techniques at the Neutral Buoyancy Laboratory (NBL) at the agency’s Johnson Space Center in Houston. The recovery team is practicing underway recovery techniques using a test version of the Orion spacecraft. Training will help the team prepare for Underway Recovery Test 5 for Exploration Mission 1 aboard the USS San Diego in the Pacific Ocean off the coast of California in October. The Ground Systems Development and Operations Program, along with the U.S. Navy and Lockheed Martin, are preparing the recovery team, hardware and operations to support EM-1 recovery.

AVTA Federal Fleet PEV Readiness Data Logging and Characterization Study: Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schey, Stephen; Francfort, Jim

2015-06-01

Collect and evaluate data on federal fleet operations as part of the Advanced Vehicle Testing Activity’s Federal Fleet Vehicle Data Logging and Characterization Study. The Advanced Vehicle Testing Activity study seeks to collect and evaluate data to validate the utilization of advanced plug-in electric vehicle (PEV) transportation. This report summarizes the fleets studied to identify daily operational characteristics of select vehicles and report findings on vehicle and mission characterizations to support the successful introduction of PEVs into the agencies’ fleets. Individual observations of these selected vehicles provide the basis for recommendations related to electric vehicle adoption and whether a batterymore » electric vehicle or plug-in hybrid electric vehicle (collectively referred to as PEVs) can fulfill the mission requirements.« less

Small Scale Mass Flow Plug Calibration

NASA Technical Reports Server (NTRS)

Sasson, Jonathan

2015-01-01

A simple control volume model has been developed to calculate the discharge coefficient through a mass flow plug (MFP) and validated with a calibration experiment. The maximum error of the model in the operating region of the MFP is 0.54%. The model uses the MFP geometry and operating pressure and temperature to couple continuity, momentum, energy, an equation of state, and wall shear. Effects of boundary layer growth and the reduction in cross-sectional flow area are calculated using an in- integral method. A CFD calibration is shown to be of lower accuracy with a maximum error of 1.35%, and slower by a factor of 100. Effects of total pressure distortion are taken into account in the experiment. Distortion creates a loss in flow rate and can be characterized by two different distortion descriptors.

40 CFR 144.63 - Financial assurance for plugging and abandonment.

Code of Federal Regulations, 2011 CFR

2011-07-01

... Regional Administrator consents to termination of the policy by the owner or operator as specified in... the trust agreement to the Regional Administrator. An owner or operator of a Class I well injecting hazardous waste must submit the originally signed duplicate of the trust agreement to the Regional...

76 FR 1644 - Biweekly Notice; Applications and Amendments to Facility Operating Licenses Involving No...

Federal Register 2010, 2011, 2012, 2013, 2014

2011-01-11

... tubesheet in that region. At normal operating pressures, leakage from primary water stress corrosion... cause failure. The EDG reliability will thereby be potentially increased by reducing the stresses on the..., ``Bases for Plugging Degraded PWR [pressurized-water reactor] Steam Generator Tubes,'' margins against...

40 CFR 144.52 - Establishing permit conditions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... comply with the financial responsibility requirements of subpart F of this part. (8) Mechanical integrity. A permit for any Class I, II or III well or injection project which lacks mechanical integrity shall... Administrator. (6) After a cessation of operations of two years the owner or operator shall plug and abandon the...

40 CFR 144.52 - Establishing permit conditions.

Code of Federal Regulations, 2013 CFR

2013-07-01

... the financial responsibility requirements set forth in § 146.85 of this chapter. (8) Mechanical integrity. A permit for any Class I, II, III or VI well or injection project which lacks mechanical... cessation of operations of two years the owner or operator shall plug and abandon the well in accordance...

40 CFR 144.52 - Establishing permit conditions.

Code of Federal Regulations, 2012 CFR

2012-07-01

... the financial responsibility requirements set forth in § 146.85 of this chapter. (8) Mechanical integrity. A permit for any Class I, II, III or VI well or injection project which lacks mechanical... cessation of operations of two years the owner or operator shall plug and abandon the well in accordance...

40 CFR 144.52 - Establishing permit conditions.

Code of Federal Regulations, 2014 CFR

2014-07-01

... the financial responsibility requirements set forth in § 146.85 of this chapter. (8) Mechanical integrity. A permit for any Class I, II, III or VI well or injection project which lacks mechanical... cessation of operations of two years the owner or operator shall plug and abandon the well in accordance...

40 CFR 144.52 - Establishing permit conditions.

Code of Federal Regulations, 2011 CFR

2011-07-01

... the financial responsibility requirements set forth in § 146.85 of this chapter. (8) Mechanical integrity. A permit for any Class I, II, III or VI well or injection project which lacks mechanical... cessation of operations of two years the owner or operator shall plug and abandon the well in accordance...

30 CFR 250.602 - Equipment movement.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Workover Operations § 250.602 Equipment movement... surface with a pump-through-type tubing plug and at the surface with a closed master valve prior to moving...

30 CFR 250.502 - Equipment movement.

Code of Federal Regulations, 2010 CFR

2010-07-01

... Mineral Resources MINERALS MANAGEMENT SERVICE, DEPARTMENT OF THE INTERIOR OFFSHORE OIL AND GAS AND SULPHUR OPERATIONS IN THE OUTER CONTINENTAL SHELF Oil and Gas Well-Completion Operations § 250.502 Equipment movement... surface with a pump-through-type tubing plug and at the surface with a closed master valve prior to moving...

Experimental investigation of gas hydrate formation, plugging and transportability in partially dispersed and water continuous systems

NASA Astrophysics Data System (ADS)

Vijayamohan, Prithvi

As oil/gas subsea fields mature, the amount of water produced increases significantly due to the production methods employed to enhance the recovery of oil. This is true especially in the case of oil reservoirs. This increase in the water hold up increases the risk of hydrate plug formation in the pipelines, thereby resulting in higher inhibition cost strategies. A major industry concern is to reduce the severe safety risks associated with hydrate plug formation, and significantly extending subsea tieback distances by providing a cost effective flow assurance management/safety tool for mature fields. Developing fundamental understanding of the key mechanistic steps towards hydrate plug formation for different multiphase flow conditions is a key challenge to the flow assurance community. Such understanding can ultimately provide new insight and hydrate management guidelines to diminish the safety risks due to hydrate formation and accumulation in deepwater flowlines and facilities. The transportability of hydrates in pipelines is a function of the operating parameters, such as temperature, pressure, fluid mixture velocity, liquid loading, and fluid system characteristics. Specifically, the hydrate formation rate and plugging onset characteristics can be significantly different for water continuous, oil continuous, and partially dispersed systems. The latter is defined as a system containing oil/gas/water, where the water is present both as a free phase and partially dispersed in the oil phase (i.e., entrained water in the oil). Since hydrate formation from oil dispersed in water systems and partially dispersed water systems is an area which is poorly understood, this thesis aims to address some key questions in these systems. Selected experiments have been performed at the University of Tulsa flowloop to study the hydrate formation and plugging characteristics for the partially dispersed water/oil/gas systems as well as systems where the oil is completely dispersed in water. These experiments indicate that the partially dispersed systems tend to be problematic and are more severe cases with respect to flow assurance when compared to systems where the water is completely dispersed in oil. We have found that the partially dispersed systems are distinct, and are not an intermediate case between water dominated, and water-in-oil emulsified systems. Instead the experiments indicate that the hydrate formation and plugging mechanism for these systems are very complex. Hydrate growth is very rapid for such systems when compared to 100% water cut systems. The plugging mechanism for these systems is a combination of various phenomena (wall growth, agglomeration, bedding/settling, etc). Three different oils with different viscosities have been used to investigate the transportability of hydrates with respect to oil properties. The experiments indicate that the transportability of hydrates increases with increase in oil viscosity. The data from the tests performed provide the basis for a mechanistic model for hydrate formation and plugging in partially dispersed systems. It is found that in systems that were in stratified flow regime before hydrate onset, the hydrates eventually settled on the pipe walls thereby decreasing the flow area for the flow of fluids. In systems that were in the slug flow regime before hydrate formation, moving beds of hydrates were the main cause for plugging. In both the flow regimes, the systems studied entered a plugging regime beyond a certain hydrate concentration. This is termed as φplugging onset and can be used as an indicator to calculate the amount of hydrates that can be transported safely without requiring any additional treatment for a given set of flow characteristics. A correlation to calculate this hydrate concentration based on easily accessible parameters is developed in terms of flow characteristics and oil properties. The work performed in this thesis has enhanced the understanding of the hydrate plug mechanism in pipelines having high amounts of water. This work has also shown the effect of hydrate formation in different flow regimes thereby shedding light on the effects of hydrates on multiphase flow and vice versa. Lessons resulting from this work could be incorporated into flow assurance models, as well as operating company production strategies to reduce or mitigate hydrate plugging risks in complex multiphase systems.

Comparison of remote video and diver's direct observations to quantify reef fishes feeding on benthos in coral and rocky reefs.

PubMed

Longo, G O; Floeter, S R

2012-10-01

This study compared remote underwater video and traditional direct diver observations to assess reef fish feeding impact on benthos across multiple functional groups within different trophic categories (e.g. herbivores, zoobenthivores and omnivores) and in two distinct reef systems: a subtropical rocky reef and a tropical coral reef. The two techniques were roughly equivalent, both detecting the species with higher feeding impact and recording similar bite rates, suggesting that reef fish feeding behaviour at the study areas are not strongly affected by the diver's presence. © 2012 The Authors. Journal of Fish Biology © 2012 The Fisheries Society of the British Isles.

Decompression sickness in a vegetarian diver: are vegetarian divers at risk? A case report.

PubMed

van Hulst, Robert A; van der Kamp, Wim

2010-01-01

We present a case of a diver who suffered decompression sickness (DCS), but who also was a strict vegetarian for more than 10 years. He presented with symptoms of tingling of both feet and left hand, weakness in both legs and sensory deficits for vibration and propriocepsis after two deep dives with decompression. The initial clinical features of this case were most consistent with DCS, possibly because of a vulnerable spinal cord due to cobalamin deficiency neuropathy. This case illustrates the similarities between DCS and a clinically defined vitamin B12 deficiency. The pathophysiology of vitamin B12 deficiency and common pathology and symptoms of DCS are reviewed.

Operating and Maintaining Energy Smart Schools Action Plan Template - All Action Plans

DOE Office of Scientific and Technical Information (OSTI.GOV)

none,

2009-07-01

EnergySmart Schools action plan templates for benchmarking, lighting, HVAC, water heating, building envelope, transformer, plug loads, kitchen equipment, swimming pool, building automation system, other.

Experimental Study on Environment Friendly Tap Hole Clay for Blast Furnace

NASA Astrophysics Data System (ADS)

Siva kumar, R.; Mohammed, Raffi; Srinivasa Rao, K.

2018-03-01

Blast furnace (BF) is the best possible route of iron production available. Blast furnace is a high pressure vessel where iron ore is melted and liquid iron is produced. The liquid iron is tapped through the hole in Blast Furnace called tap hole. The tapped liquid metal flowing through the tap hole is plugged using a clay called tap hole clay. Tap hole clay (THC) is a unshaped refractory used to plug the tap hole. The tap hole clay extruded through the tap hole using a gun. The tap hole clay is designed to expand and plug the tap hole. The tap hole filled with clay is drilled using drill bit and the hole made through the tap hole to tap the liquid metal accumulated inside the furnace. The number of plugging and drilling varies depending on the volume of the furnace. The tap hole clay need to have certain properties to avoid problems during plugging and drilling. In the present paper tap hole clay properties in industrial use was tested and studied. The problems were identified related to tap hole clay manufacturing. Experiments were conducted in lab scale to solve the identified problems. The present composition was modified with experimental results. The properties of the modified tap hole clay were found suitable and useful for blast furnace operation with lab scale experimental results.

NREL Helps Utilities Develop Next Generation Plug-in Hybrid Electric Trucks

Science.gov Websites

operation, and fine-tune the design of such vehicles before expanding their use in the PG&E or other Vehicle Performance Data Based on Real-World Operation "NREL has been working with PG&E to accessories function in real-world operation." To date, NREL has captured and is currently analyzing four

DEVICE FOR CHARGING OR DISCHARGING

DOEpatents

Untemeyer, S.; Hutter, E.

1959-01-13

A loading and unloading device is presented for loading objects into and unloading them from an apparatus in which fluid under pressure is employed, such as a heterogeneous rcactor wherein the fuel elements are in the form of slugs. This device is comprised essentially of a cylindrical member disposed coaxially with and as an accessible extension of an internal tube member of the apparatus in which the objects, or fuel elements, are normally disposed in use. The outermost end of the cylindrical extension is closed by a removable seal plug. The lower end of the cylindrical extension is separated from the intennal tube by a disk valve which is operated externally. A source of pressure fluid and a drain line are provided in communication with the interior of the cylindrical extension. To load an object into the internal tube, the disk valve is closed, the seal plug is renmoved, an object is placed in the cylindrical extension, and the seal plug is replaced. The disk valve is then opened and ihe pressure of the fluid within the cylindrical extension is increased until it is greater than the pressure within the internal tube and forces the object out of the cylindrical extension into the internal tube. To remove an object from the tube the disk valve is opened and the intenior of thc cylindnical extension is connected to the drain line whereby the operating pressure within the intennal tube forces the object out of the internal tube and up into the cylindrical extension. The disk valve is then closed and the seal plug is removed to permit removal of the object.

Military Curricula for Vocational & Technical Education. Diver Second Class, 15-3.

ERIC Educational Resources Information Center

Ohio State Univ., Columbus. National Center for Research in Vocational Education.

This curriculum outline, student guide, and instructor guide for a secondary-postsecondary-level course in scuba diving (diver second class) is one of a number of military-developed curriculum packages selected for adaptation to vocational instruction and curriculum development in a civilian setting. Purpose stated for the 425-hour course is to…

STS-26 MS Hilmers floats in life raft during JSC WETF exercises

NASA Technical Reports Server (NTRS)

1988-01-01

STS-26 Discovery, Orbiter Vehicle (OV) 103, Mission Specialist (MS) David C. Hilmers, wearing the newly designed launch and entry suit (LES), floats in single-occupant life raft in JSC Weightless Environment Training Facility (WETF) Bldg 29 pool. Hilmers pulls his legs into the inflating raft while he is assisted by two SCUBA-equipped divers. The simulation of the escape and rescue operations utilized the crew escape system (CES) pole method of egress from the Space Shuttle.

STS-26 Commander Hauck floats in life raft during JSC WETF exercises

NASA Technical Reports Server (NTRS)

1988-01-01

STS-26 Discovery, Orbiter Vehicle (OV) 103, Commander Frederick H. Hauck, wearing the newly designed launch and entry suit (LES), floats in single-occupant life raft in JSC Weightless Environment Training Facility (WETF) Bldg 29 pool. Removing water from his raft, Hauck awaits the assistance of SCUBA-equipped divers (one of whom is partially visible at bottom right). The simulation of the escape and rescue operations utilized the crew escape system (CES) pole method of egress from the Space Shuttle.

Alterations in Body Fluid Balance During Fin Swimming in 29 °C Water in a Population of Special Forces Divers.

PubMed

Castagna, O; Desruelle, A V; Blatteau, J E; Schmid, B; Dumoulin, G; Regnard, J

2015-12-01

Highly trained "combat swimmers" encounter physiological difficulties when performing missions in warm water. The aim of this study was to assess the respective roles of immersion and physical activity in perturbing fluid balance of military divers on duty in warm water. 12 trained divers performed 2 dives each (2 h, 3 m depth) in fresh water at 29 °C. Divers either remained Static or swam continuously (Fin) during the dive. In the Fin condition, oxygen consumption and heart rate were 2-fold greater than during the Static dive. Core and skin temperatures were also higher (Fin: 38.5±0.4 °C and 36.2±0.3 °C and Static: 37.2±0.3 °C and 34.3±0.3 °C; respectively p=0.0002 and p=0.0003). During the Fin dive, the average mass loss was 989 g (39% urine loss, 41% sweating and 20% insensible water loss and blood sampling); Static divers lost 720 g (84% urine loss, 2% sweating and 14% insensible water loss and blood sampling) (p=0.003). In the Fin condition, a greater decrease in total body mass and greater sweating occurred, without effects on circulating renin and aldosterone concentrations; diuresis was reduced, and plasma volume decreased more than in the Static condition. © Georg Thieme Verlag KG Stuttgart · New York.

Beneficial effect of enriched air nitrox on bubble formation during scuba diving. An open-water study.

PubMed

Brebeck, Anne-Kathrin; Deussen, Andreas; Range, Ursula; Balestra, Costantino; Cleveland, Sinclair; Schipke, Jochen D

2018-03-01

Bubble formation during scuba diving might induce decompression sickness. This prospective randomised and double-blind study included 108 advanced recreational divers (38 females). Fifty-four pairs of divers, 1 breathing air and the other breathing nitrox28 undertook a standardised dive (24 ± 1 msw; 62 ± 5min) in the Red Sea. Venous gas bubbles were counted (Doppler) 30-<45 min (early) and 45-60 min (late) post-dive at jugular, subclavian and femoral sites. Only 7% (air) vs. 11% (air28®) (n.s.) were bubble-free after a dive. Independent of sampling time and breathing gas, there were more bubbles in the jugular than in the femoral vein. More bubbles were counted in the air-group than in the air28-group (pooled vein: early: 1845 vs. 948; P = 0.047, late: 1817 vs. 953; P = 0.088). The number of bubbles was sex-dependent. Lastly, 29% of female air divers but only 14% of male divers were bubble-free (P = 0.058). Air28® helps to reduce venous gas emboli in recreational divers. The bubble number depended on the breathing gas, sampling site and sex. Thus, both exact reporting the dive and in particular standardising sampling characteristics seem mandatory to compare results from different studies to further investigate the hitherto incoherent relation between inert gas bubbles and DCS.

Portable musical instrument amplifier

DOEpatents

Christian, David E.

1990-07-24

The present invention relates to a musical instrument amplifier which is particularly useful for electric guitars. The amplifier has a rigid body for housing both the electronic system for amplifying and processing signals from the guitar and the system's power supply. An input plug connected to and projecting from the body is electrically coupled to the signal amplifying and processing system. When the plug is inserted into an output jack for an electric guitar, the body is rigidly carried by the guitar, and the guitar is operatively connected to the electrical amplifying and signal processing system without use of a loose interconnection cable. The amplifier is provided with an output jack, into which headphones are plugged to receive amplified signals from the guitar. By eliminating the conventional interconnection cable, the amplifier of the present invention can be used by musicians with increased flexibility and greater freedom of movement.

Plug and Process Loads Capacity and Power Requirements Analysis

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sheppy, M.; Gentile-Polese, L.

2014-09-01

This report addresses gaps in actionable knowledge that would help reduce the plug load capacities designed into buildings. Prospective building occupants and real estate brokers lack accurate references for plug and process load (PPL) capacity requirements, so they often request 5-10 W/ft2 in their lease agreements. Limited initial data, however, suggest that actual PPL densities in leased buildings are substantially lower. Overestimating PPL capacity leads designers to oversize electrical infrastructure and cooling systems. Better guidance will enable improved sizing and design of these systems, decrease upfront capital costs, and allow systems to operate more energy efficiently. The main focus ofmore » this report is to provide industry with reliable, objective third-party guidance to address the information gap in typical PPL densities for commercial building tenants. This could drive changes in negotiations about PPL energy demands.« less

Use of a contoured bioresorbable plate with a hemostatic plug to control life-threatening bleeding from the superior sagittal sinus during hemispherotomy: technical note.

PubMed

Tuite, Gerald F; Carey, Carolyn M; Nelson, William W; Raffa, Scott J; Winesett, S Parrish

2016-10-01

Profuse bleeding originating from an injured cerebral sinus can be a harrowing experience for any surgeon, particularly during an operation on a young child. Common surgical remedies include sinus ligation, primary repair, placement of a hemostatic plug, and patch or venous grafting that may require temporary stenting. In this paper the authors describe the use of a contoured bioresorbable plate to hold a hemostatic plug in place along a tear in the inferomedial portion of a relatively inaccessible part of the posterior segment of the superior sagittal sinus in an 11-kg infant undergoing hemispherotomy for epilepsy. This variation on previously described hemostatic techniques proved to be easy, effective, and ultimately lifesaving. Surgeons may find this technique useful in similar dire circumstances when previously described techniques are ineffective or impractical.

Psychological and physical correlates of musculoskeletal symptoms in male professional divers and offshore workers

PubMed Central

2013-01-01

Background Underwater divers are more likely to complain of musculoskeletal symptoms than a control population. Accordingly, we conducted a study to determine whether musculoskeletal symptoms reflected observable physical disorder, to ascertain the relationship between symptoms and measures of mood, memory and executive function and to assess any need for future screening. Methods A 10% random sample of responders to a prior postal health questionnaire was examined (151 divers, 120 non-diving offshore workers). Participants underwent physical examination and a neuropsychological test battery for memory and executive function. Participants also completed the Hospital Anxiety and Depression Scale for anxiety (HADSa) and depression (HADSd), and questionnaires for physical health-related quality of life (SF36 PCS), mental health-related quality of life (SF36 MCS), memory (Cognitive Failures Questionnaire (CFQ), Prospective and Retrospective Memory Questionnaire (PRMQ)), executive function (dysexecutive syndrome questionnaire (DEX)), musculoskeletal symptoms (MSS) and general unrelated symptom reporting. Results Of participants with moderate/severe musculoskeletal symptoms, 52% had physical signs, and of participants with no symptoms, 73% had no physical signs. There was no difference in the prevalence of signs or symptoms between groups. Musculoskeletal symptoms were associated with lower SF36 PCS for both groups. In divers, musculoskeletal symptoms were associated with higher general unrelated symptom reporting and poorer scoring for HADSa, PRMQ, CFQ and DEX with scores remaining within the normative range. A positive physical examination was associated with general unrelated symptom reporting in divers. There were no differences in neuropsychological test scores attributable to either group or musculoskeletal symptoms. Conclusions Musculoskeletal symptoms were associated with physical signs, but this was not a strong effect. Reporting of musculoskeletal symptoms by the divers studied was also associated with a tendency to report symptoms generally or somatisation, and caution should be exercised regarding their interpretation as an indication of physical disease or their use for health screening. PMID:23849557

The Race Toward Becoming Operationally Responsive in Space

NASA Astrophysics Data System (ADS)

Nagy, J.; Hernandez, V.; Strunce, R.

The US Air Force Research Laboratory (AFRL) is currently supporting the joint Operationally Responsive Space (ORS) program with two aggressive research space programs. The goal of the ORS program is to improve the responsiveness of space capabilities to meet national security requirements. ORS systems aim to provide operational space capabilities as well as flexibility and responsiveness to the theater that do not exist today. ORS communication, navigation, and Intelligence, Surveillance and Reconnaissance (ISR) satellites are being designed to rapidly meet near term space needs of in-theater tactical forces by supporting contingency operations, such as increased communication bandwidth, and ISR imagery over the theater for a limited period to support air, ground, and naval force missions. This paper will discuss how AFRL/RHA is supporting the ORS effort and describe the hardware and software being developed with a particular focus on the Satellite Design Tool for plug-n-play satellites (SDT). AFRLs Space Vehicles Directorate together with the Scientific Simulation, Inc. was the first to create the Plug-and-play (PnP) satellite design for rapid construction through modular components that encompass the structural panels, as well as the guidance and health/status components. Expansion of the PnP technology is currently being led by AFRL's Human Effectiveness Directorate and Star Technologies Corp. by pushing the boundaries of mobile hardware and software technology through the development of the teams "Training and Tactical ORS Operations (TATOO) Laboratory located in Great Falls, VA. The TATOO Laboratory provides a computer-based simulation environment directed at improving Warfighters space capability responsiveness by delivering the means to create and exercise methods of in-theater tactical satellite tasking for and by the Warfighter. In an effort to further support the evolution of ORS technologies with Warfighters involvement, Star recently started coordinating the integration of the TATOO Laboratory with a satellite robotics test bed. Accessible via the TATOO Lab, the robotics test bed will be used to demonstrate and evaluate leading edge satellite technologies, such as Guidance Navigation and Control, attitude control, formation flying, and plug-and-play electronics. The test bed will consist of a Mission Control Center with wireless control and telemetry, an exceptionally flat and smooth floor area, and two robotic satellite simulators equipped with next generation plug-and-play hardware.

A Plug and Play Pathway Approach for Operations Management Games Development

ERIC Educational Resources Information Center

Tan, Kim Hua; Tse, Ying Kei; Chung, Pui Ling

2010-01-01

Many researchers have advocated the use of games (and simulations) to enhance students' learning. Research has shown that in order to promote a deeper understanding of material, students ought to be engaged with what they are doing. However, there are limited interactive games for classroom teaching, especially within the operations management…

Plug and Play Solar Power: Simplifying the Integration of Solar Energy in Hybrid Applications; Cooperative Research and Development Final Report, CRADA Number CRD-13-523

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lundstrom, Blake R.

The Commonwealth Scientific and Industrial Research Organisation (CSIRO) is Australia's national science agency. CSIRO received funding from the Australian Solar Institute (ASI) for the United States-Australia Solar Energy Collaboration (USASEC) project 1-USO032 Plug and Play Solar Power: Simplifying the Integration of Solar Energy in Hybrid Applications (Broader Project). The Australian Solar Institute (ASI) operated from August 2009 to December 2012 before being merged into the Australian Renewable Energy Agency (ARENA). The Broader Project sought to simplify the integration, accelerate the deployment, and lower the cost of solar energy in hybrid distributed generation applications by creating plug and play solar technology.more » CSIRO worked with the National Renewable Energy Laboratory (NREL) as set out in a Joint Work Statement to review communications protocols relevant to plug-and-play technology and perform prototype testing in its Energy System Integration Facility (ESIF). For the avoidance of doubt, this CRADA did not cover the whole of the Broader Project and only related to the work described in the Joint Work Statement, which was carried out by NREL.« less

Effects of spark plug configuration on combustion and emission characteristics of a LPG fuelled lean burn SI engine

NASA Astrophysics Data System (ADS)

Ravi, K.; Khan, Manazir Ahmed; Pradeep Bhasker, J.; Porpatham, E.

2017-11-01

Introduction of technological innovation in automotive engines in reducing pollution and increasing efficiency have been under contemplation. Gaseous fuels have proved to be a promising way to reduce emissions in Spark Ignition (SI) engines. In particular, LPG settled to be a favourable fuel for SI engines because of their higher hydrogen to carbon ratio, octane rating and lower emissions. Wide ignition limits and efficient combustion characteristics make LPG suitable for lean burn operation. But lean combustion technology has certain drawbacks like poor flame propagation, cyclic variations etc. Based on copious research it was found that location, types and number of spark plug significantly influence in reducing cyclic variations. In this work the influence of single and dual spark plugs of conventional and surface discharge electrode type were analysed. Dual surface discharge electrode spark plug enhanced the brake thermal efficiency and greatly reduced the cyclic variations. The experimental results show that rate of heat release and pressure rise was more and combustion duration was shortened in this configuration. On the emissions front, the NOx emission has increased whereas HC and CO emissions were reduced under lean condition.

Selecting a Control Strategy for Plug and Process Loads

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lobato, C.; Sheppy, M.; Brackney, L.

2012-09-01

Plug and Process Loads (PPLs) are building loads that are not related to general lighting, heating, ventilation, cooling, and water heating, and typically do not provide comfort to the building occupants. PPLs in commercial buildings account for almost 5% of U.S. primary energy consumption. On an individual building level, they account for approximately 25% of the total electrical load in a minimally code-compliant commercial building, and can exceed 50% in an ultra-high efficiency building such as the National Renewable Energy Laboratory's (NREL) Research Support Facility (RSF) (Lobato et al. 2010). Minimizing these loads is a primary challenge in the designmore » and operation of an energy-efficient building. A complex array of technologies that measure and manage PPLs has emerged in the marketplace. Some fall short of manufacturer performance claims, however. NREL has been actively engaged in developing an evaluation and selection process for PPLs control, and is using this process to evaluate a range of technologies for active PPLs management that will cap RSF plug loads. Using a control strategy to match plug load use to users' required job functions is a huge untapped potential for energy savings.« less

Plug cluster module demonstration

NASA Technical Reports Server (NTRS)

Rousar, D. C.

1978-01-01

The low pressure, film cooled rocket engine design concept developed during two previous ALRC programs was re-evaluated for application as a module for a plug cluster engine capable of performing space shuttle OTV missions. The nominal engine mixture ratio was 5.5 and the engine life requirements were 1200 thermal cycles and 10 hours total operating life. The program consisted of pretest analysis; engine tests, performed using residual components; and posttest analysis. The pretest analysis indicated that operation of the operation of the film cooled engine at O/F = 5.5 was feasible. During the engine tests, steady state wall temperature and performance measurement were obtained over a range of film cooling flow rates, and the durability of the engine was demonstrated by firing the test engine 1220 times at a nominal performance ranging from 430 - 432 seconds. The performance of the test engine was limited by film coolant sleeve damage which had occurred during previous testing. The post-test analyses indicated that the nominal performance level can be increased to 436 seconds.

INL Fleet Vehicle Characterization Study for the U.S. Department of Navy

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bennett, Brion Dale; Francfort, James Edward; Smart, John Galloway

Battelle Energy Alliance, LLC, managing and operating contractor for the U.S. Department of Energy’s Idaho National Laboratory, is the lead laboratory for U.S. Department of Energy Advanced Vehicle Testing. Battelle Energy Alliance, LLC collected and evaluated data on federal fleet operations as part of the Advanced Vehicle Testing Activity’s Federal Fleet Vehicle Data Logging and Characterization Study. The Advanced Vehicle Testing Activity’s study seeks to collect and evaluate data to validate use of advanced plug-in electric vehicle (PEV) transportation. This report focuses on US Department of Navy's fleet to identify daily operational characteristics of select vehicles and report findings onmore » vehicle and mission characterizations to support the successful introduction of PEVs into the agency’s fleets. Individual observations of these selected vehicles provide the basis for recommendations related to electric vehicle adoption and whether a battery electric vehicle or plug-in hybrid electric vehicle (collectively referred to as PEVs) can fulfill the mission requirements.« less

Moon Diver: A Discovery Mission Concept for Understanding the History of the Mare Basalts Through the Exploration of a Lunar Mare Pit

NASA Astrophysics Data System (ADS)

Kerber, L.; Nesnas, I.; Keszthelyi, L.; Head, J. W.; Denevi, B.; Hayne, P. O.; Mitchell, K.; Ashley, J. W.; Whitten, J. L.; Stickle, A. M.; Parness, A.; McGarey, P.; Paton, M.; Donaldson-Hanna, K.; Anderson, R. C.; Needham, D.; Isaacson, P.; Jozwiak, L.; Bleacher, J.; Parcheta, C.

2018-04-01

Moon Diver is a Discovery-class mission concept designed to explore a lunar mare pit. It would be the first mission to examine an in-place bedrock stratigraphy on the Moon, and the first to venture into the subsurface of another planetary body.

Fatal dissecting aneurysm of the aorta in a diver.

PubMed

James, R; Hayman, J A

1986-07-01

A 20-yr-old trained sports diver developed severe chest pain shortly after decompressing from a 40 m repetitive freshwater sinkhole dive, and died 6 h later. An autopsy examination showed a dissecting aneurysm of the aorta with rupture into the left pleural cavity. The relationship between the fatal event and the diving is discussed.

IMPROVED WELL PLUGGING EQUIPMENT AND WASTE MANGEMENT TECHNIQUES EXCEED ALARA GOALS AT THE OAK RIDGE NATIONAL LABORATORY

DOE Office of Scientific and Technical Information (OSTI.GOV)

Whiteside, R.; Pawlowicz, R.; Whitehead, L.

2002-02-25

In 2000, Bechtel Jacobs Company LLC (BJC) contracted Tetra Tech NUS, Inc. (TtNUS) and their sub-contractor, Texas World Operations, Inc. (TWO), to plug and abandon (P&A) 111 wells located in the Melton Valley area of Oak Ridge National Laboratory (ORNL). One hundred and seven of those wells were used to monitor fluid movement and subsurface containment of the low level radioactive liquid waste/grout slurry that was injected into the Pumpkin Valley Shale Formation, underlying ORNL. Four wells were used as hydrofracture injection wells to emplace the waste in the shale formation. Although the practice of hydrofracturing was and is consideredmore » by many to pose no threat to human health or the environment, the practice was halted in 1982 after the Federal Underground Injection Control regulations were enacted by United States Environmental Protection Agency (USEPA) making it necessary to properly close the wells. The work is being performed for the United States Department of Energy Oak Ridge Operations (DOE ORO). The project team is using the philosophy of minimum waste generation and the principles of ALARA (As Low As Reasonably Achievable) as key project goals to minimize personnel and equipment exposure, waste generation, and project costs. Achievement of these goals was demonstrated by the introduction of several new pieces of custom designed well plugging and abandonment equipment that were tested and used effectively during field operations. Highlights of the work performed and the equipment used are presented.« less

Comparison Between Botulinum Toxin A Injection and Lacrimal Punctal Plugs for the Control of Post-LASIK Dry Eye Manifestations: A Prospective Study.

PubMed

Fouda, Sameh M; Mattout, Hala K

2017-06-01

Laser in situ keratomelieusis (LASIK) is one of the commonest refractive procedures performed nowadays. The dry eye problem is nearly universal in all patients after LASIK and it can be so annoying that the post-operative patient satisfaction is sometimes precluded. Conventional treatment includes the use of artificial tears. Alternative methods such as punctal plugs and botulinum toxin injection can be used for the management of post-LASIK dry eye. The aim of this study is to compare botulinum toxin injection in the orbicularis muscle to lacrimal punctal plugs for the control of post-LASIK dry eye manifestations. This is a prospective study that included 60 patients who had LASIK eye surgery for correction of refractive errors. Patients were randomly assigned to one of three methods of dry eye management; the first method was conventional medical treatment with preservative-free tear substitutes only (group A: 20 patients = 40 eyes); the second method was intraoperative injection of botulinum toxin A (BTA) in the orbicularis muscle below the lower punctum of both eyes (group B: 20 patients = 40 eyes) and the third method was intraoperative insertion of temporary extended duration silicone punctal plugs in the lower punctum of both eyes (group C: 20 patients = 40 eyes). In the first follow-up visit after 2 weeks, the two test groups (B, C) showed a statistically significant increase in both tear film break up time (TBUT) and Schirmer test score with a decrease in the OSDI score and daily frequency of lubricants used in comparison to the control group A. These differences were maintained in the next follow-up visit but they became statistically insignificant at the 3rd and 6th post-operative months. Complications were encountered more in the punctal plug patients (60%) than in BTA patients (25%) and this difference was statistically significant. The use of BTA injection to control dry eye symptoms by inducing temporary punctal ectropion is an effective method to improve patient satisfaction after LASIK eye surgery. It has higher level of patient satisfaction and fewer complications in comparison to punctal plugs or topical standard dry eye treatment.

Assessing Caribbean Shallow and Mesophotic Reef Fish Communities Using Baited-Remote Underwater Video (BRUV) and Diver-Operated Video (DOV) Survey Techniques.

PubMed

Andradi-Brown, Dominic A; Macaya-Solis, Consuelo; Exton, Dan A; Gress, Erika; Wright, Georgina; Rogers, Alex D

2016-01-01

Fish surveys form the backbone of reef monitoring and management initiatives throughout the tropics, and understanding patterns in biases between techniques is crucial if outputs are to address key objectives optimally. Often biases are not consistent across natural environmental gradients such as depth, leading to uncertainty in interpretation of results. Recently there has been much interest in mesophotic reefs (reefs from 30-150 m depth) as refuge habitats from fishing pressure, leading to many comparisons of reef fish communities over depth gradients. Here we compare fish communities using stereo-video footage recorded via baited remote underwater video (BRUV) and diver-operated video (DOV) systems on shallow and mesophotic reefs in the Mesoamerican Barrier Reef, Caribbean. We show inconsistent responses across families, species and trophic groups between methods across the depth gradient. Fish species and family richness were higher using BRUV at both depth ranges, suggesting that BRUV is more appropriate for recording all components of the fish community. Fish length distributions were not different between methods on shallow reefs, yet BRUV recorded more small fish on mesophotic reefs. However, DOV consistently recorded greater relative fish community biomass of herbivores, suggesting that studies focusing on herbivores should consider using DOV. Our results highlight the importance of considering what component of reef fish community researchers and managers are most interested in surveying when deciding which survey technique to use across natural gradients such as depth.

Assessing Caribbean Shallow and Mesophotic Reef Fish Communities Using Baited-Remote Underwater Video (BRUV) and Diver-Operated Video (DOV) Survey Techniques

PubMed Central

Macaya-Solis, Consuelo; Exton, Dan A.; Gress, Erika; Wright, Georgina; Rogers, Alex D.

2016-01-01

Fish surveys form the backbone of reef monitoring and management initiatives throughout the tropics, and understanding patterns in biases between techniques is crucial if outputs are to address key objectives optimally. Often biases are not consistent across natural environmental gradients such as depth, leading to uncertainty in interpretation of results. Recently there has been much interest in mesophotic reefs (reefs from 30–150 m depth) as refuge habitats from fishing pressure, leading to many comparisons of reef fish communities over depth gradients. Here we compare fish communities using stereo-video footage recorded via baited remote underwater video (BRUV) and diver-operated video (DOV) systems on shallow and mesophotic reefs in the Mesoamerican Barrier Reef, Caribbean. We show inconsistent responses across families, species and trophic groups between methods across the depth gradient. Fish species and family richness were higher using BRUV at both depth ranges, suggesting that BRUV is more appropriate for recording all components of the fish community. Fish length distributions were not different between methods on shallow reefs, yet BRUV recorded more small fish on mesophotic reefs. However, DOV consistently recorded greater relative fish community biomass of herbivores, suggesting that studies focusing on herbivores should consider using DOV. Our results highlight the importance of considering what component of reef fish community researchers and managers are most interested in surveying when deciding which survey technique to use across natural gradients such as depth. PMID:27959907

Get the Power You Need, When and Where You Need It Aboard the International Space Station (ISS) Using the ISS Plug-In Plan (IPiP) Requirement Request Process

NASA Technical Reports Server (NTRS)

Moore, Kevin D.

2017-01-01

Trying to get your experiment aboard ISS? You likely will need power. Many enditem providers do. ISS Plug-In Plan (IPiP) supports power and data for science, Payloads (or Utilization), vehicle systems, and daily operations through the Electrical Power System (EPS) Secondary Power/Data Subsystem. Yet limited resources and increasing requirements continue to influence decisions on deployment of ISS end items. Given the fluid launch schedule and the rapidly- increasing number of end item providers requiring power support, the focus of the Plug-In Plan has evolved from a simple FIFO recommendation to provide power to end item users, to anticipating future requirements by judicious development and delivery of support equipment (cables, power supplies, power strips, and alternating current (AC) power inverters), employing innovative deployment strategies, and collaborating on end item development. This paper describes the evolution of the ISS Program Office, Engineering Directorate, Flight Operations Directorate (FOD), International Partners and the end item provider relationship and how collaboration successfully leverages unique requirements with limited on- board equipment and resources, tools and processes which result in more agile integration, and describes the process designed for the new ISS end item provider to assure that their power requirements will be met.

Three phase AC motor controller

DOEpatents

Vuckovich, Michael; Wright, Maynard K.; Burkett, John P.

1984-03-20

A motor controller for a three phase AC motor (10) which is adapted to operate bidirectionally from signals received either from a computer (30) or a manual control (32). The controller is comprised of digital logic circuit means which implement a forward and reverse command signal channel (27, 29) for the application of power through the forward and reverse power switching relays (16, 18, 20, 22). The digital logic elements are cross coupled to prevent activation of both channels simultaneously and each includes a plugging circuit (65, 67) for stopping the motor upon the removal of control signal applied to one of the two channels (27, 29) for a direction of rotation desired. Each plugging circuit (65, 67) includes a one-shot pulse signal generator (88, 102) which outputs a single pulse signal of predetermined pulsewidth which is adapted to inhibit further operation of the application of power in the channel which is being activated and to apply a reversal command signal to the other channel which provides a reversed phase application of power to the motor for a period defined by the pulse-width output of the one-shot signal generator to plug the motor (10) which will then be inoperative until another rotational command signal is applied to either of the two channels.

Monitoring techniques for high accuracy interference fit assembly processes

NASA Astrophysics Data System (ADS)

Liuti, A.; Vedugo, F. Rodriguez; Paone, N.; Ungaro, C.

2016-06-01

In the automotive industry, there are many assembly processes that require a high geometric accuracy, in the micrometer range; generally open-loop controllers cannot meet these requirements. This results in an increased defect rate and high production costs. This paper presents an experimental study of interference fit process, aimed to evaluate the aspects which have the most impact on the uncertainty in the final positioning. The press-fitting process considered, consists in a press machine operating with a piezoelectric actuator to press a plug into a sleeve. Plug and sleeve are designed and machined to obtain a known interference fit. Differential displacement and velocity measurements of the plug with respect to the sleeve are measured by a fiber optic differential laser Doppler vibrometer. Different driving signals of the piezo actuator allow to have an insight into the differences between a linear and a pulsating press action. The paper highlights how the press-fit assembly process is characterized by two main phases: the first is an elastic deformation of the plug and sleeve, which produces a reversible displacement, the second is a sliding of the plug with respect to the sleeve, which results in an irreversible displacement and finally realizes the assembly. The simultaneous measurements of the displacement and the force have permitted to define characteristic features in the signal useful to identify the start of the irreversible movement. These indicators could be used to develop a control logic in a press assembly process.

40 CFR 147.2918 - Permit application information.

Code of Federal Regulations, 2010 CFR

2010-07-01

... location, depth, date drilled, and record of plugging and/or completion. (3) Operating data: (i) Maximum... logging and testing data on the well (for existing wells, i.e., wells to be converted or wells previously...

Flow equation for porous plug and capillary tube flow restrictors

NASA Technical Reports Server (NTRS)

Davis, W. S.

1972-01-01

Development of flow measuring apparatus for determining low flow performance of resistojet thruster is discussed. Diagram of test equipment is presented. Operation of test equipment is described and numerical relationships are explained.

The Cartesian Diver as an Aid for Teaching Respiratory Physiology

ERIC Educational Resources Information Center

Fitch, Greg K.

2004-01-01

The mechanism by which air enters the mammalian lung is difficult for many students of physiology. In particular, some students have trouble seeing how pressure can be transmitted through a fluid such as the intrapleural fluid and how the magnitude of that pressure can change. A Cartesian diver, an old-time child's toy, may be used as a visual aid…

Scuba diving & underwater cultural resources: differences in environmental beliefs, ascriptions of responsibility, and management preferences based on level of development

Treesearch

Sharon L. Todd; Tiffany Cooper; Alan R. Graefe

2001-01-01

This study examined SCUBA divers' level of development in relationship to environmental beliefs, ascriptions of responsibility, and management preferences concerning the use and management of New York's Great Lakes' underwater cultural resources. More than 850 New York State divers were surveyed during the fall of 1999, ranging from novices to experts...

Nitrogen narcosis and tactile shape memory in low visibility.

PubMed

van Wijk, Charles H; Meintjes, W A J

2014-01-01

Commercial diving often occurs in low visibility, where divers are reliant on their tactile senses. This study examined the effect of nitrogen narcosis on tactile memory for shapes as well as the influence of psychological and biographical factors on this relationship. This crossover study tested 139 commercial divers in a dry hyperbaric chamber at 101.325 and 607.95 kPa (1 and 6 atmospheres absolute/atm abs). Divers memorized shapes while blindfolded, using their tactile senses only. Delayed recall was measured at the surface after each dive. Psychological and biographical data were also collected. A significant effect of hyperbaric pressure on tactile memory was demonstrated, and a further effect of sequence of testing found. Thus, divers' delayed shape recall deteriorated by 8% after learning material at depth, compared to learning on the surface. There were also significant but small effects of psychological and biographical markers on tactile memory performance, with lower trait anxiety associated with better recall, and lower education associated with poorer recall. The findings emphasize the importance of utilizing other forms of recording of events or objects at depth, particularly in conditions of low visibility during deeper diving, to aid memory encoding and subsequent recall at the surface.

Preliminary observations on the effect of hypoxic and hyperbaric stress on pulmonary gas exchange in breath-hold divers.

PubMed

Garbella, Erika; Piarulli, Andrea; Fornai, Edo; Pingitore, Alessandro; Prediletto, Renato

2011-06-01

To evaluate pulmonary alveolar-capillary membrane integrity and ventilation/perfusion mismatch after breath-hold diving. Pulmonary diffusing capacity to carbon monoxide (DLCO) and nitric oxide (DLNO), haemoglobin (Hb) and haematocrit (Hct) were measured in six elite divers before and at 2, 10 and 25 minutes after a maximal breath-hold dive to a depth of 10 metres' sea water. Compared to pre-dive, DLCO showed a slight increase at 2 minutes in five subjects and a tendency to decrease at 25 minutes (P < 0.001) in all subjects. DLNO showed an increase at 10 minutes in three divers and a slight decrease at 25 minutes in five subjects. There was a small but significant (P < 0.001) increase in Hb and Hct at 2 minutes, possibly affecting the DLCO measurements. An early but transient increase in DLCO in five divers may reflect the central shift in blood volume during a breath-hold dive. The late parallel decrease in DLCO and DLNO likely reflects alveolar-capillary distress (interstitial oedema). The DLNO increase in three subjects at 10 minutes may suggest ventilation/perfusion mismatch.

Cold injury to a diver's hand after a 90-min dive in 6 degrees C water.

PubMed

Laden, Gerard D M; Purdy, Gerard; O'Rielly, Gerard

2007-05-01

We present here a case of non-freezing cold injury (NFCI) in a sport scuba diver. There are similarities between the presenting symptoms of NFCI and decompression sickness, e.g., pain and/or altered sensation in an extremity, often reported as numbness. In both conditions patients have been known to describe their lower limbs or feet as feeling woolly. Both conditions are the result of environmental exposure. Additionally, there are no good (high sensitivity and specificity) diagnostic tests for either condition. Diagnosis is made based on patient history, clinical presentation, and examination. NFCI is most frequently seen in military personnel, explorers, and the homeless. When affecting the feet of soldiers it is often referred to as "trench foot." Historically, NFCI has been and continues to be of critical importance in infantry warfare in cold and wet environments. A high priority should be given to prevention of NFCI during military operational planning. With the advent of so-called "technical diving" characterized by going deeper for longer (often in cold water) and adventure tourism, this extremely painful condition is likely to increase in prevalence. NFCI is treated symptomatically.

Friction pull plug welding: chamfered heat sink pull plug design

NASA Technical Reports Server (NTRS)

Coletta, Edmond R. (Inventor); Cantrell, Mark A. (Inventor)

2002-01-01

Friction Pull Plug Welding (FPPW) is a solid state repair process for defects up to one inch in length, only requiring single sided tooling (OSL) for usage on flight hardware. Experimental data has shown that the mass of plug heat sink remaining above the top of the plate surface after a weld is completed (the plug heat sink) affects the bonding at the plug top. A minimized heat sink ensures complete bonding of the plug to the plate at the plug top. However, with a minimal heat sink three major problems can arise, the entire plug could be pulled through the plate hole, the central portion of the plug could be separated along grain boundaries, or the plug top hat can be separated from the body. The Chamfered Heat Sink Pull Plug Design allows for complete bonding along the ISL interface through an outside diameter minimal mass heat sink, while maintaining enough central mass in the plug to prevent plug pull through, central separation, and plug top hat separation.

Press-fit stability of an osteochondral autograft: Influence of different plug length and perfect depth alignment.

PubMed

Kock, Niels B; Van Susante, Job L C; Buma, Pieter; Van Kampen, Albert; Verdonschot, Nico

2006-06-01

Osteochondral autologous transplantation is used for the treatment of full-thickness articular cartilage lesions of a joint. Press-fit stability is an important factor for good survival of the transplanted plugs. 36 plugs of three different lengths were transplanted in fresh-frozen human knees. On one condyle, 3 plugs were exactly matched to the depth of the recipient site ("bottomed" plugs) and on the opposite condyle 3 plugs were 5 mm shorter than the depth of the recipient site ("unbottomed" plugs). Plugs were left protruding and then pushed in until flush, and then to 2 mm below flush level, using a loading apparatus. Longer plugs needed higher forces to begin displacement. At flush level, bottomed plugs needed significantly higher forces than unbottomed plugs to become displaced below flush level (mean forces of 404 N and 131 N, respectively). Shorter bottomed plugs required higher forces than longer bottomed ones. Bottomed plugs generally provide much more stability than unbottomed ones. Short bottomed plugs are more stable than long bottomed plugs. Thus, in clinical practice it is advisable to use short bottomed plugs. If, however, unbottomed plugs are still chosen, the longer the plug the higher the resulting stability will be because of higher frictional forces.

Highly-reliable operation of 638-nm broad stripe laser diode with high wall-plug efficiency for display applications

NASA Astrophysics Data System (ADS)

Yagi, Tetsuya; Shimada, Naoyuki; Nishida, Takehiro; Mitsuyama, Hiroshi; Miyashita, Motoharu

2013-03-01

Laser based displays, as pico to cinema laser projectors have gathered much attention because of wide gamut, low power consumption, and so on. Laser light sources for the displays are operated mainly in CW, and heat management is one of the big issues. Therefore, highly efficient operation is necessitated. Also the light sources for the displays are requested to be highly reliable. 638 nm broad stripe laser diode (LD) was newly developed for high efficiency and highly reliable operation. An AlGaInP/GaAs red LD suffers from low wall plug efficiency (WPE) due to electron overflow from an active layer to a p-cladding layer. Large optical confinement factor (Γ) design with AlInP cladding layers is adopted to improve the WPE. The design has a disadvantage for reliable operation because the large Γ causes high optical density and brings a catastrophic optical degradation (COD) at a front facet. To overcome the disadvantage, a window-mirror structure is also adopted in the LD. The LD shows WPE of 35% at 25°C, highest record in the world, and highly stable operation at 35°C, 550 mW up to 8,000 hours without any catastrophic optical degradation.

Modular "plug-and-play" capsules for multi-capsule environment in the gastrointestinal tract.

PubMed

Phee, S J; Ting, E K; Lin, L; Huynh, V A; Kencana, A P; Wong, K J; Tan, S L

2009-01-01

The invention of wireless capsule endoscopy has opened new ways of diagnosing and treating diseases in the gastrointestinal tract. Current wireless capsules can perform simple operations such as imaging and data collection (like temperature, pressure, and pH) in the gastrointestinal tract. Researchers are now focusing on adding more sophisticated functions such as drug delivery, surgical clips/tags deployment, and tissue samples collection. The finite on-board power on these capsules is one of the factors that limits the functionalities of these wireless capsules. Thus multiple application-specific capsules would be needed to complete an endoscopic operation. This would give rise to a multi-capsule environment. Having a modular "plug-and-play" capsule design would facilitate doctors in configuring multiple application-specific capsules, e.g. tagging capsule, for use in the gastrointestinal tract. This multi-capsule environment also has the advantage of reducing power consumption through asymmetric multi-hop communication.

Self-learning control system for plug-in hybrid vehicles

DOEpatents

DeVault, Robert C [Knoxville, TN

2010-12-14

A system is provided to instruct a plug-in hybrid electric vehicle how optimally to use electric propulsion from a rechargeable energy storage device to reach an electric recharging station, while maintaining as high a state of charge (SOC) as desired along the route prior to arriving at the recharging station at a minimum SOC. The system can include the step of calculating a straight-line distance and/or actual distance between an orientation point and the determined instant present location to determine when to initiate optimally a charge depleting phase. The system can limit extended driving on a deeply discharged rechargeable energy storage device and reduce the number of deep discharge cycles for the rechargeable energy storage device, thereby improving the effective lifetime of the rechargeable energy storage device. This "Just-in-Time strategy can be initiated automatically without operator input to accommodate the unsophisticated operator and without needing a navigation system/GPS input.

Comprehensive Performance Limits for Divers’ Underwater Breathing Gear: Consequences of Adopting Diver-Focused Limits

DTIC Science & Technology

2007-01-01

Tidal PCO 2," Undersea Biomed. Res., Vol. 15 (Suppl., 1988), p. 39. 17. D. Warkander, G. K. Nagasawa, W. T. Norfleet, and C. E. G. Lundgren, "Dyspnea...Workshop, Bethesda, MD, 1989. 35. D. E. Warkander, W. T. Norfleet, G. K. Nagasawa, and C. E. G. Lundgren, "CO2 Retention with Minimal Symptoms but Severe

Device for Automated Cutting and Transfer of Plant Shoots

NASA Technical Reports Server (NTRS)

Cipra, Raymond; Das, Hari; Ali, Khaled; Hong, Dennis

2003-01-01

A device that enables the automated cutting and transfer of plant shoots is undergoing development for use in the propagation of plants in a nursery or laboratory. At present, it is standard practice for a human technician to use a knife and forceps to cut, separate, and grasp a plant shoot. The great advantage offered by the present device is that its design and operation are simpler than would be those of a device based on the manual cutting/separation/grasping procedure. [The present device should not be confused with a prior device developed for partly the same purpose and described in Compliant Gripper for a Robotic Manipulator (NPO-21104), NASA Tech Briefs, Vol. 27, No. 3 (March 2003), page 59.]. The device (see figure) includes a circular tube sharpened at its open (lower) end and mounted on a robotic manipulator at its closed (upper) end. The robotic manipulator simply pushes the sharpened open end of the tube down onto a bed of plants and rotates a few degrees clockwise then counterclockwise about the vertical axis, causing the tube to cut a cylindrical plug of plant material. Exploiting the natural friction between the tube and plug, the tube retains the plug, without need for a gripping mechanism and control. The robotic manipulator then retracts the tube, translates it to a new location over a plant-growth tray, and inserts the tube part way into the growth medium at this location in the tray. A short burst of compressed air is admitted to the upper end of the tube to eject the plug of plant material and drive it into the growth medium. A prototype has been tested and verified to function substantially as intended. It is projected that in the fully developed robotic plant-propagation system, the robot control system would include a machine- vision subsystem that would automatically guide the robotic manipulator in choosing the positions from which to cut plugs of plant material. Planned further development efforts also include more testing and refinement of the design and operation described above.

Iraqi Perspectives Project. Primary Source Materials for Saddam and Terrorism: Emerging Insights from Captured Iraqi Documents. Volume 5 (Redacted)

DTIC Science & Technology

2007-11-01

whether the latter are serving near or far in espionage missions. This experiment started on 6/25/1958. It involved telepathy , and it ended with a 70...Atlantic. Rather, a new kind ofweapon was used in this operation, namely parapsychology - by using a specialized diver and telepathy . (11-22... dream that a flame emerged from him, spread throughout the land, and started to bum everyone that had an encounter with it. He told of his dream to

Day 3 on the USS Anchorage for the Recovery of Orion

NASA Image and Video Library

2014-12-03

On the third day of preparations for recovery of Orion, U.S. Navy divers in two rigid hull inflatable boats and two Zodiac boats practice recovery procedures nearby the USS Anchorage in the Pacific Ocean about 600 miles off the coast of Baja, California. NASA, Lockheed Martin and U.S. Navy personnel are preparing for recovery of the Orion crew module, forward bay cover and parachutes after its return from space and splashdown in the Pacific Ocean. The Ground Systems Development and Operations Program is leading the recovery efforts.

Day 3 on the USS Anchorage for the Recovery of Orion

NASA Image and Video Library

2014-12-03

On the third day of preparations for recovery of Orion after its splashdown in the Pacific Ocean, U.S. Navy Divers prepare to embark from the well deck of the USS Anchorage in a rigid hull Zodiac boat about 600 miles off the coast of Baja, California. NASA, Lockheed Martin and U.S. Navy personnel are preparing for recovery of the crew module, forward bay cover and parachutes on its return from space and splashdown in the Pacific Ocean. The Ground Systems Development and Operations Program is leading the recovery efforts.

Orion Splashdown Recovery

NASA Image and Video Library

2014-12-05

NASA's Orion spacecraft splashed down in the Pacific Ocean after its first flight test atop a Delta IV Heavy rocket from Space Launch Complex 37 at Cape Canaveral Air Force Station in Florida. U.S. Navy divers in Zodiac boats prepare to recover Orion and tow her in to the well deck of the USS Anchorage. NASA's Orion spacecraft completed a two-orbit, four-and-a-half hour mission to test systems critical to crew safety, including the launch abort system, the heat shield and the parachute system. The Ground Systems Development and Operations Program is leading the recovery efforts.

Day 3 on the USS Anchorage for the Recovery of Orion

NASA Image and Video Library

2014-12-03

On the third day of preparations for recovery of Orion after its splashdown in the Pacific Ocean, U.S. Navy Divers prepare to embark from the well deck of the USS Anchorage in two rigid hull Zodiac boats about 600 miles off the coast of Baja, California. NASA, Lockheed Martin and U.S. Navy personnel are preparing for recovery of the crew module, forward bay cover and parachutes on its return from space and splashdown in the Pacific Ocean. The Ground Systems Development and Operations Program is leading the recovery efforts.

NASA Extreme Environments Mission Operations 10 - Evaluation of Robotic and Sensor Technologies for Surgery in Extreme Environments

DTIC Science & Technology

2006-11-01

ExPOC), LinkQUest, and working w/ ExPOC, go to the known locations identified in the site survey exercise. 1. Does the direction a diver is...map/ survey an area MD-5 7 April 06 08:30 & 14:20 hrs MD-9 08:15 Prior to EVA surface exploration, robotic rovers could potentially identify...What ROV tasks can be controlled from the ground and what have to be controlled from w/in the habitat SITE SURVEY ROV Objectives (all on

AVTA Federal Fleet PEV Readiness Data Logging and Characterization Study for NASA Glenn Research Center

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schey, Stephen; Francfort, Jim

The Advanced Vehicle Testing Activity’s study seeks to collect and evaluate data to validate the utilization of advanced plug-in electric vehicle (PEV) transportation. This report focuses on the NASA Glenn Research Center (GRC) fleet to identify daily operational characteristics of select vehicles and report findings on vehicle and mission characterizations to support the successful introduction of PEVs into the agencies’ fleets. Individual observations of these selected vehicles provide the basis for recommendations related to electric vehicle adoption and whether a battery electric vehicle or plug-in hybrid electric vehicle (collectively referred to as PEVs) can fulfill the mission requirements.

Nonexpansiveness of a linearized augmented Lagrangian operator for hierarchical convex optimization

NASA Astrophysics Data System (ADS)

Yamagishi, Masao; Yamada, Isao

2017-04-01

Hierarchical convex optimization concerns two-stage optimization problems: the first stage problem is a convex optimization; the second stage problem is the minimization of a convex function over the solution set of the first stage problem. For the hierarchical convex optimization, the hybrid steepest descent method (HSDM) can be applied, where the solution set of the first stage problem must be expressed as the fixed point set of a certain nonexpansive operator. In this paper, we propose a nonexpansive operator that yields a computationally efficient update when it is plugged into the HSDM. The proposed operator is inspired by the update of the linearized augmented Lagrangian method. It is applicable to characterize the solution set of recent sophisticated convex optimization problems found in the context of inverse problems, where the sum of multiple proximable convex functions involving linear operators must be minimized to incorporate preferable properties into the minimizers. For such a problem formulation, there has not yet been reported any nonexpansive operator that yields an update free from the inversions of linear operators in cases where it is utilized in the HSDM. Unlike previously known nonexpansive operators, the proposed operator yields an inversion-free update in such cases. As an application of the proposed operator plugged into the HSDM, we also present, in the context of the so-called superiorization, an algorithmic solution to a convex optimization problem over the generalized convex feasible set where the intersection of the hard constraints is not necessarily simple.

Effect of Biodegradable Scleral Plugs Containing Curcumin on Proliferative Vitreoretinopathy.

PubMed

Zhang, Jun; Zhou, Nalei; Zhang, Bin; Ma, Jingxue

2018-01-01

This study aimed to explore the inhibitory effect of biodegradable scleral plugs containing curcumin on rabbits with proliferative vitreoretinopathy (PVR). The biodegradable scleral plugs containing curcumin were prepared by dissolving PLGA [poly(lactide-co-glycolide)] and curcumin. In total, 30 rabbits were divided into 2 groups: the model group received a vitreous injection of self-blood, and the treatment group received a vitreous injection of self-blood plus biodegradable scleral implants containing 1.5 mg of curcumin. On days 1, 3, 7, 14, 21, and 28 after the operation, clinical observations and PVR classifications were performed. Then, after vitreous samples were collected, different cytokines were detected using antibody chip technology. The scleral plug was 5 mm in length and 1 mm in diameter. Clinical observation showed marked inflammation in the model group. The development grade of PVR in the treatment group was lower than that in the model group (p < 0.05). The outcome of antibody chip technology showed that the expression levels of IL-1α, IL-1β, IL-8, leptin, MMP-9, NCAM, and TNF-α in the treatment group at different time points were significantly lower than those in the model group (p < 0.05). Curcumin might have great potential as a therapeutic agent for PVR by inhibiting various inflammatory factors. © 2017 S. Karger AG, Basel.

Middleware for Plug and Play Integration of Heterogeneous Sensor Resources into the Sensor Web

PubMed Central

Toma, Daniel M.; Jirka, Simon; Del Río, Joaquín

2017-01-01

The study of global phenomena requires the combination of a considerable amount of data coming from different sources, acquired by different observation platforms and managed by institutions working in different scientific fields. Merging this data to provide extensive and complete data sets to monitor the long-term, global changes of our oceans is a major challenge. The data acquisition and data archival procedures usually vary significantly depending on the acquisition platform. This lack of standardization ultimately leads to information silos, preventing the data to be effectively shared across different scientific communities. In the past years, important steps have been taken in order to improve both standardization and interoperability, such as the Open Geospatial Consortium’s Sensor Web Enablement (SWE) framework. Within this framework, standardized models and interfaces to archive, access and visualize the data from heterogeneous sensor resources have been proposed. However, due to the wide variety of software and hardware architectures presented by marine sensors and marine observation platforms, there is still a lack of uniform procedures to integrate sensors into existing SWE-based data infrastructures. In this work, a framework aimed to enable sensor plug and play integration into existing SWE-based data infrastructures is presented. First, an analysis of the operations required to automatically identify, configure and operate a sensor are analysed. Then, the metadata required for these operations is structured in a standard way. Afterwards, a modular, plug and play, SWE-based acquisition chain is proposed. Finally different use cases for this framework are presented. PMID:29244732

[Plug-technique for umbilical hernia repair in the adult].

PubMed

Brancato, G; Privitera, A; Gandolfo, L; Donati, M; Caglià, P

2002-02-01

Umbilical hernia represents 6% of all abdominal wall hernias in the adult. Surgical repair should always be carried out due to possible occurrence of complications. Aim of this paper is to evaluate the efficacy of the plug-technique. From October 1995 to April 2000, the authors performed 21 operations for acquired umbilical hernia with a defect smaller than 4 cm. Local anesthesia was used and a light intravenous sedation added in particularly anxious patients. The repair was achieved by insertion of a polypropylene dart plug sutured to the margins of the hernial defect. All patients were up and about straightaway and were discharged within 24 hours of surgery. Postoperative pain was mild and required hospital analgesia in only 19% of cases and domiciliary analgesia in 24%. During a follow-up ranging from 6 to 60 months (mean 30), only one recurrence has been recorded. This tension-free technique allows immediate rehabilitation, with few complications and a low recurrence rate.

Annular flow diverter valve

DOEpatents

Rider, Robert L.

1980-01-01

A valve for diverting flow from the center of two concentric tubes to the annulus between the tubes or, operating in the reverse direction, for mixing fluids from concentric tubes into a common tube and for controlling the volume ratio of said flow consists of a toroidal baffle disposed in sliding engagement with the interior of the inner tube downstream of a plurality of ports in the inner tube, a plurality of gates in sliding engagement with the interior of the inner tube attached to the baffle for movement therewith, a servomotor having a bullet-shaped plug on the downstream end thereof, and drive rods connecting the servomotor to the toroidal baffle, the servomotor thereby being adapted to move the baffle into mating engagement with the bullet-shaped plug and simultaneously move the gates away from the ports in the inner tube and to move the baffle away from the bullet-shaped plug and simultaneously move the gates to cover the ports in the inner tube.

A Plug and Play GNC Architecture Using FPGA Components

NASA Technical Reports Server (NTRS)

KrishnaKumar, K.; Kaneshige, J.; Waterman, R.; Pires, C.; Ippoloito, C.

2005-01-01

The goal of Plug and Play, or PnP, is to allow hardware and software components to work together automatically, without requiring manual setup procedures. As a result, new or replacement hardware can be plugged into a system and automatically configured with the appropriate resource assignments. However, in many cases it may not be practical or even feasible to physically replace hardware components. One method for handling these types of situations is through the incorporation of reconfigurable hardware such as Field Programmable Gate Arrays, or FPGAs. This paper describes a phased approach to developing a Guidance, Navigation, and Control (GNC) architecture that expands on the traditional concepts of PnP, in order to accommodate hardware reconfiguration without requiring detailed knowledge of the hardware. This is achieved by establishing a functional based interface that defines how the hardware will operate, and allow the hardware to reconfigure itself. The resulting system combines the flexibility of manipulating software components with the speed and efficiency of hardware.

Managing Dive Tourism for the Sustainable Use of Coral Reefs: Validating Diver Perceptions of Attractive Site Features

NASA Astrophysics Data System (ADS)

Uyarra, Maria C.; Watkinson, Andrew R.; Côté, Isabelle M.

2009-01-01

It has been argued that strategies to manage natural areas important for tourism and recreation should integrate an understanding of tourist preferences for specific natural features. However, the accuracy of tourist recalled perceptions of environmental attributes, which are usually derived from post hoc surveys and used to establish management priorities, is currently unmeasured. We tested the validity of the relationship between tourist-stated preferences and actual condition of coral reefs around the Caribbean island of Bonaire. Using standardized questionnaires, we asked 200 divers to select their most and least favorite dive sites and the attributes that contributed to that selection. We also carried out ecological surveys at 76 of the 81 dives sites around the island to assess the actual conditions of the attributes indicated as important for site selection. Fish- and coral-related attributes were key features affecting dive enjoyment. In general, divers appeared to be able to perceive differences between sites in the true condition of biological attributes such as fish species richness, total number of fish schools, live coral cover, coral species richness, and reef structural complexity, although men and women divers differed in their ability to perceive/recall some of the attributes. Perceived differences in environmental attributes, such as surface conditions, underwater current, and the likelihood of encountering rare fish and sea turtles, were not empirically validated. The fact that divers perceive correctly differences in the condition of some of the key biological attributes that affect dive enjoyment reinforces the need to maintain overall reef condition at satisfactory levels. However, variation in accuracy of perceptions owing to demographic factors and attribute type suggests the need for caution when using public perceptions to develop environmental management strategies, particularly for coral reefs.

Managing dive tourism for the sustainable use of coral reefs: validating diver perceptions of attractive site features.

PubMed

Uyarra, Maria C; Watkinson, Andrew R; Côté, Isabelle M

2009-01-01

It has been argued that strategies to manage natural areas important for tourism and recreation should integrate an understanding of tourist preferences for specific natural features. However, the accuracy of tourist recalled perceptions of environmental attributes, which are usually derived from post hoc surveys and used to establish management priorities, is currently unmeasured. We tested the validity of the relationship between tourist-stated preferences and actual condition of coral reefs around the Caribbean island of Bonaire. Using standardized questionnaires, we asked 200 divers to select their most and least favorite dive sites and the attributes that contributed to that selection. We also carried out ecological surveys at 76 of the 81 dives sites around the island to assess the actual conditions of the attributes indicated as important for site selection. Fish- and coral-related attributes were key features affecting dive enjoyment. In general, divers appeared to be able to perceive differences between sites in the true condition of biological attributes such as fish species richness, total number of fish schools, live coral cover, coral species richness, and reef structural complexity, although men and women divers differed in their ability to perceive/recall some of the attributes. Perceived differences in environmental attributes, such as surface conditions, underwater current, and the likelihood of encountering rare fish and sea turtles, were not empirically validated. The fact that divers perceive correctly differences in the condition of some of the key biological attributes that affect dive enjoyment reinforces the need to maintain overall reef condition at satisfactory levels. However, variation in accuracy of perceptions owing to demographic factors and attribute type suggests the need for caution when using public perceptions to develop environmental management strategies, particularly for coral reefs.

Sink fast and swim harder! Round-trip cost-of-transport for buoyant divers.

PubMed

Miller, Patrick J O; Biuw, Martin; Watanabe, Yuuki Y; Thompson, Dave; Fedak, Mike A

2012-10-15

Efficient locomotion between prey resources at depth and oxygen at the surface is crucial for breath-hold divers to maximize time spent in the foraging layer, and thereby net energy intake rates. The body density of divers, which changes with body condition, determines the apparent weight (buoyancy) of divers, which may affect round-trip cost-of-transport (COT) between the surface and depth. We evaluated alternative predictions from external-work and actuator-disc theory of how non-neutral buoyancy affects round-trip COT to depth, and the minimum COT speed for steady-state vertical transit. Not surprisingly, the models predict that one-way COT decreases (increases) when buoyancy aids (hinders) one-way transit. At extreme deviations from neutral buoyancy, gliding at terminal velocity is the minimum COT strategy in the direction aided by buoyancy. In the transit direction hindered by buoyancy, the external-work model predicted that minimum COT speeds would not change at greater deviations from neutral buoyancy, but minimum COT speeds were predicted to increase under the actuator disc model. As previously documented for grey seals, we found that vertical transit rates of 36 elephant seals increased in both directions as body density deviated from neutral buoyancy, indicating that actuator disc theory may more closely predict the power requirements of divers affected by gravity than an external work model. For both models, minor deviations from neutral buoyancy did not affect minimum COT speed or round-trip COT itself. However, at body-density extremes, both models predict that savings in the aided direction do not fully offset the increased COT imposed by the greater thrusting required in the hindered direction.

Decreasing carbon monoxide in the diving air of artisanal fishermen in the Yucatán peninsula by separation of engine exhaust from compressor intake.

PubMed

Chin, Walter; Huchim-Lara, Oswaldo; Salas, Silvia

2016-01-01

Artisanal fishermen in the Yucatán Peninsula utilize hookah dive systems (HDS). The air compressors in these HDS are not filtered, and the intake is near the engine exhaust. This proximity allows carbon monoxide (CO) from the exhaust to directly enter the HDS volume tank and contaminate the fishermen diver's air supply. Conservative safety standards permit a diver's air supply to contain 10 parts per million (ppm) of CO. This study quantified the levels of CO in the diver's air supply both before and after physical separation of the engine exhaust from the compressor intake. CO levels in seven volume tanks were analyzed before and after a 1-inch hose was attached to the compressor intake and elevated 5 feet above the engine exhaust. The tanks were drained and refilled before collecting each set of pre- and post-intervention gas samples. Four CO measurements were collected before and after the intervention from each volume tank. A C-Squared© CO Analyzer (± 1 ppm), calibrated with a Praxair 70 ppm CON2 gas (± 5%), was used to analyze the gas samples. A paired samples t-test shows a statistically significant difference in average CO values before and after the intervention (t = 6.8674, df: 27; p⟨0.0001). The physical separation of the engine exhaust from the compressor intake reduced the CO contamination of the diver air supply by 72%. This intervention could be applied to the hookah systems in the rest of the fishing cooperative to reduce the divers' risk of CO poisoning. Copyright© Undersea and Hyperbaric Medical Society.

Very Few Exercise-Induced Arterialized Gas Bubbles Reach the Cerebral Vasculature.

PubMed

Barak, Otto F; Madden, Dennis; Lovering, Andrew T; Lambrechts, Kate; Ljubkovic, Marko; Dujic, Zeljko

2015-09-01

Arterialization of venous gas emboli (VGE) formed after surfacing from SCUBA diving can become arterial gas emboli (AGE) through intrapulmonary arterial-venous anastomoses that open with exercise. We recruited twenty patent foramen ovale-negative SCUBA divers and conducted a field and a laboratory study with the aim of investigating the appearance of AGE in intracranial vessels. At the field, they performed a single dive to a depth of 18-m sea water with a 47-min bottom time and a direct ascent to the surface. Transthoracic echocardiography was used to score VGE and AGE, and transcranial Doppler was used to visualize middle and posterior cerebral arteries with automated objective bubble detection. Observations were conducted for 45-min after dive at rest and at the laboratory after agitated saline injection at rest and throughout an incremental cycle supine exercise test until exhaustion and for 10 min of recovery. After resurfacing, all divers presented endogenous VGE and arterialization was present in three divers. Saline contrast injection led to AGE in nine of 19 subjects at rest. AGE that reached the cerebral arteries after dive were recorded in two divers at 60 W, three at 90 W, five at 120 W, six at 150 W, and four at 180 W and in three, four, five, nine, and nine, respectively, after saline contrast injection in the laboratory. All divers had AGE grades of 1 or 2, and only single AGE reached the cerebral vasculature. These data suggest that few emboli of venous origin reach the brain through exercise-induced intrapulmonary arterial-venous anastomoses but cerebral embolization is not high risk in the studied population.

Alternative Fuels Data Center: How Do Hybrid Electric Cars Work?

Science.gov Websites

, and the air/fuel mix is ignited by the spark from a spark plug. Power electronics controller: This maintains a proper operating temperature range of the engine, electric motor, power electronics, and other

"Invisible" Killer

MedlinePlus

... allow CO to come indoors. In addition, install battery-operated CO alarms or plug-in CO alarms with battery back-up in your home. Every home should ... Test your CO alarms frequently and replace dead batteries. A CO alarm can provide added protection, but ...

78 FR 44599 - Notice of Lodging of Proposed Consent Decree Under the Clean Water Act

Federal Register 2010, 2011, 2012, 2013, 2014

2013-07-24

... plugs at Defendant's existing and new natural gas wells within EPA Region 3; implementation of standard operating procedures for tank loading and unloading; and an obligation to increase recycling of produced...

Electric vehicle fleet implications and analysis : final research project report.

DOT National Transportation Integrated Search

2016-11-01

The objective of this project was to evaluate the implementation and effectiveness of : electric vehicles (EVs) used in fleet operations. The study focuses on Battery-Electric : Vehicles (BEVs) and Plug-In Hybrid Electric Vehicles (PHEVs); collective...

Research on Nitride Thin Films, Advanced Plasma Diagnostics, and Charged-Particle Processes

DTIC Science & Technology

2006-07-01

Additionally, these components are being placed closer to the point of use--requiring that they operate in extreme temperature environments ...reasons for component failure. To operate in extreme temperature environments , electronic and electrical components must withstand higher ambient...hybrid and plug-in hybrid-powered automobiles, heart defibrillators , and industrial equipment will benefit from a new generation of capacitors. High

AUTOMOTIVE DIESEL MAINTENANCE 1. UNIT XXVIII, I--CATERPILLAR STARTING (PONEY) ENGINE (PART II), II--UNDERSTANDING MORE ABOUT STARTING DEVICES.

ERIC Educational Resources Information Center

Human Engineering Inst., Cleveland, OH.

THIS MODULE OF A 30-MODULE COURSE IS DESIGNED TO DEVELOP AN UNDERSTANDING OF THE OPERATION AND MAINTENANCE OF DIESEL ENGINE STARTING ENGINES. TOPICS ARE (1) STARTING ENGINE MAGNETO (WICO), (2) MAGNETO MAINTENANCE, (3) SPARK PLUGS, (4) GENERAL DESCRIPTION (STARTING DEVICES), (5) OPERATING (STARTING DEVICES), (6) LUBRICATION (STARTING DEVICES), (7)…

Underway Recovery Test 6 (URT-6) - Day 5 Activities

NASA Image and Video Library

2018-01-21

Navy Diver 2nd Class Laethem and his fellow divers get briefed before heading out to sea to recover the Orion test article during Underway Recovery Test 6 off the coast of San Diego. Kennedy Space Center’s NASA Recovery Team works with the U.S. Navy to improve recovery procedures and hardware ahead of Orion's next flight, Exploration Mission-1, when it splashes down in the Pacific Ocean.

Air Purity in Diving from Submarines. 1. Review and Preliminary Analyses

DTIC Science & Technology

1987-12-01

Nathaniel Howard for technical assistance, and Susan Cecire for editorial assistance. iv INTRODUCTION The need for divers to use compressed air from...pneumatic control systems) and emergency submarine functions, and submarine interior air is frequently compressed back into the bank which will cycle...breathe the interior air for long periods, so why the concern for divers? First, the processes of compression (by multi-stage oil lubricated

Incidence of CNS Oxygen Toxicity with Mild Hyperoxia: A Literature and Data Review

DTIC Science & Technology

2013-04-01

multi-depth profiles.16,17 One diver reported numbness, tingling, poor concentration and dizziness after only 5 minutes. One diver reported tinnitus ...function dives,22, 24, 26, 28 the symptoms considered to be CNS oxygen toxicity during the training dives--nausea, dizziness, tinnitus ...models accumulate risk from prior exposure but do not (and cannot) consider other possible changes caused by immediate history , e.g., sensitization or

MOCHA - Multi-Study Ocean Acoustics Human Effects Analysis

DTIC Science & Technology

2015-09-30

understanding of the response of marine mammals to navy sonar and other acoustic stimuli, by maximizing the information gain from Behavioral Response Studies...focussed on a functional/taxonomic group of marine mammals (deep divers, other odontocetes, pilot whales and baleen whales). We began with deep divers...Controlled Exposure Experiments component of the Marine Mammals and Biology Program, and it will also address broader commitments of the Navy for

Modular radiochemistry synthesis system

DOEpatents

Satyamurthy, Nagichettiar; Barrio, Jorge R.; Amarasekera, Bernard; Van Dam, Michael R.; Olma, Sebastian; Williams, Dirk; Eddings, Mark; Shen, Clifton Kwang-Fu

2016-11-01

A modular chemical production system includes multiple modules for performing a chemical reaction, particularly of radiochemical compounds, from a remote location. One embodiment comprises a reaction vessel including a moveable heat source with the position thereof relative to the reaction vessel being controllable from a remote position. Alternatively the heat source may be fixed in location and the reaction vial is moveable into and out of the heat source. The reaction vessel has one or more sealing plugs, the positioning of which in relationship to the reaction vessel is controllable from a remote position. Also the one or more reaction vessel sealing plugs can include one or more conduits there through for delivery of reactants, gases at atmospheric or an elevated pressure, inert gases, drawing a vacuum and removal of reaction end products to and from the reaction vial, the reaction vial with sealing plug in position being operable at elevated pressures. The modular chemical production system is assembled from modules which can each include operating condition sensors and controllers configured for monitoring and controlling the individual modules and the assembled system from a remote position. Other modules include, but are not limited to a Reagent Storage and Delivery Module, a Cartridge Purification Module, a Microwave Reaction Module, an External QC/Analysis/Purification Interface Module, an Aliquotting Module, an F-18 Drying Module, a Concentration Module, a Radiation Counting Module, and a Capillary Reactor Module.

Modular radiochemistry synthesis system

DOEpatents

Satyamurthy, Nagichettiar; Barrio, Jorge R.; Amarasekera, Bernard; Van Dam, R. Michael; Olma, Sebastian; Williams, Dirk; Eddings, Mark; Shen, Clifton Kwang-Fu

2015-12-15

A modular chemical production system includes multiple modules for performing a chemical reaction, particularly of radiochemical compounds, from a remote location. One embodiment comprises a reaction vessel including a moveable heat source with the position thereof relative to the reaction vessel being controllable from a remote position. Alternatively the heat source may be fixed in location and the reaction vial is moveable into and out of the heat source. The reaction vessel has one or more sealing plugs, the positioning of which in relationship to the reaction vessel is controllable from a remote position. Also the one or more reaction vessel sealing plugs can include one or more conduits there through for delivery of reactants, gases at atmospheric or an elevated pressure, inert gases, drawing a vacuum and removal of reaction end products to and from the reaction vial, the reaction vial with sealing plug in position being operable at elevated pressures. The modular chemical production system is assembled from modules which can each include operating condition sensors and controllers configured for monitoring and controlling the individual modules and the assembled system from a remote position. Other modules include, but are not limited to a Reagent Storage and Delivery Module, a Cartridge Purification Module, a Microwave Reaction Module, an External QC/Analysis/Purification Interface Module, an Aliquotting Module, an F-18 Drying Module, a Concentration Module, a Radiation Counting Module, and a Capillary Reactor Module.

Modular radiochemistry synthesis system

DOEpatents

Satyamurthy, Nagichettiar; Barrio, Jorge R; Amarasekera, Bernard; Van Dam, R. Michael; Olma, Sebastian; Williams, Dirk; Eddings, Mark A; Shen, Clifton Kwang-Fu

2015-02-10

A modular chemical production system includes multiple modules for performing a chemical reaction, particularly of radiochemical compounds, from a remote location. One embodiment comprises a reaction vessel including a moveable heat source with the position thereof relative to the reaction vessel being controllable from a remote position. Alternatively the heat source may be fixed in location and the reaction vial is moveable into and out of the heat source. The reaction vessel has one or more sealing plugs, the positioning of which in relationship to the reaction vessel is controllable from a remote position. Also the one or more reaction vessel sealing plugs can include one or more conduits there through for delivery of reactants, gases at atmospheric or an elevated pressure, inert gases, drawing a vacuum and removal of reaction end products to and from the reaction vial, the reaction vial with sealing plug in position being operable at elevated pressures. The modular chemical production system is assembled from modules which can each include operating condition sensors and controllers configured for monitoring and controlling the individual modules and the assembled system from a remote position. Other modules include, but are not limited to a Reagent Storage and Delivery Module, a Cartridge Purification Module, a Microwave Reaction Module, an External QC/Analysis/Purification Interface Module, an Aliquotting Module, an F-18 Drying Module, a Concentration Module, a Radiation Counting Module, and a Capillary Reactor Module.

40 CFR 144.19 - Transitioning from Class II to Class VI.

Code of Federal Regulations, 2014 CFR

2014-07-01

... primary purpose of long-term storage into an oil and gas reservoir must apply for and obtain a Class VI...) Quality of abandoned well plugs within the area of review; (7) The owner's or operator's plan for recovery...

40 CFR 144.19 - Transitioning from Class II to Class VI.

Code of Federal Regulations, 2013 CFR

2013-07-01

... primary purpose of long-term storage into an oil and gas reservoir must apply for and obtain a Class VI...) Quality of abandoned well plugs within the area of review; (7) The owner's or operator's plan for recovery...

40 CFR 144.19 - Transitioning from Class II to Class VI.

Code of Federal Regulations, 2012 CFR

2012-07-01

... primary purpose of long-term storage into an oil and gas reservoir must apply for and obtain a Class VI...) Quality of abandoned well plugs within the area of review; (7) The owner's or operator's plan for recovery...

How Schools Can Plug the Energy Drain

ERIC Educational Resources Information Center

Nation's Schools, 1973

1973-01-01

Schools could conserve energy by following recommendations by Educational Facilities Laboratories: (1) review operations and maintenance personnel qualifications to handle mechanical-electrical equipment, (2) analyze energy consumption to identify waste sources in schools, (3) incorporate energy conservation into all architectural programs for…

Alternate tube plugging criteria for steam generator tubes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cueto-Felgueroso, C.; Aparicio, C.B.

1997-02-01

The tubing of the Steam Generators constitutes more than half of the reactor coolant pressure boundary. Specific requirements governing the maintenance of steam generator tubes integrity are set in Plant Technical Specifications and in Section XI of the ASME Boiler and Pressure Vessel Code. The operating experience of Steam Generator tubes of PWR plants has shown the existence of some types of degradatory processes. Every one of these has an specific cause and affects one or more zones of the tubes. In the case of Spanish Power Plants, and depending on the particular Plant considered, they should be mentioned themore » Primary Water Stress Corrosion Cracking (PWSCC) at the roll transition zone (RTZ), the Outside Diameter Stress Corrosion Cracking (ODSCC) at the Tube Support Plate (TSP) intersections and the fretting with the Anti-Vibration Bars (AVBs) or with the Support Plates in the preheater zone. The In-Service Inspections by Eddy Currents constitutes the standard method for assuring the SG tubes integrity and they permit the monitoring of the defects during the service life of the plant. When the degradation reaches a determined limit, called the plugging limit, the SG tube must be either repaired or retired from service by plugging. Customarily, the plugging limit is related to the depth of the defect. Such depth is typically 40% of the wall thickness of the tube and is applicable to any type of defect in the tube. In its origin, that limit was established for tubes thinned by wastage, which was the predominant degradation in the seventies. The application of this criterion for axial crack-like defects, as, for instance, those due to PWSCC in the roll transition zone, has lead to an excessive and unnecessary number of tubes being plugged. This has lead to the development of defect specific plugging criteria. Examples of the application of such criteria are discussed in the article.« less

Friction pull plug welding: chamfered heat sink pull plug design

NASA Technical Reports Server (NTRS)

Coletta, Edmond R. (Inventor); Cantrell, Mark A. (Inventor)

2005-01-01

The average strength of a pull plug weld is increased and weak bonding eliminated by providing a dual included angle at the top one third of the pull plug. Plugs using the included angle of the present invention had consistent high strength, no weak bonds and were substantially defect free. The dual angle of the pull plug body increases the heat and pressure of the weld in the region of the top one third of the plug. This allows the plug to form a tight high quality solid state bond. The dual angle was found to be successful in elimination of defects on both small and large plugs.

Friction pull plug welding: dual chamfered plate hole

NASA Technical Reports Server (NTRS)

Coletta, Edmond R. (Inventor); Cantrell, Mark A. (Inventor)

2001-01-01

Friction Pull Plug Welding (FPPW) is a solid state repair process for defects up to one inch in length, only requiring single sided tooling (OSL) for usage on flight hardware. Early attempts with FPPW followed the matching plug/plate geometry precedence of the successful Friction Push Plug Welding program, however no defect free welds were achieved due to substantial plug necking and plug rotational stalling. The dual chamfered hole has eliminated plug rotational stalling, both upon initial plug/plate contact and during welding. Also, the necking of the heated plug metal under a tensile heating/forging load has been eliminated through the usage of the dual chamfered plate hole.

Clearance of a Mucus Plug

NASA Astrophysics Data System (ADS)

Bian, Shiyao; Zheng, Ying; Grotberg, James B.

2008-11-01

Mucus plugging may occur in pulmonary airways in asthma, chronic obstructive pulmonary disease (COPD) and cystic fibrosis. How to clear the mucus plug is essential and of fundamental importance. Mucus is known to have a yield stress and a mucus plug behaves like a solid plug when the applied stresses are below its yield stress τy. When the local stresses reaches τy, the plug starts to move and can be cleared out of the lung. It is then of great importance to examine how the mucus plug deforms and what is the minimum pressure required to initiate its movement. The present study used the finite element method (FEM) to study the stress distribution and deformation of a solid mucus plug under different pressure loads using ANSYS software. The maximum shear stress is found to occur near the rear transition region of the plug, which can lead to local yielding and flow. The critical pressure increases linearly with the plug length and asymptotes when the plug length is larger than the half channel width. Experimentally a mucus simulant is used to study the process of plug deformation and critical pressure difference required for the plug to propagate. Consistently, the fracture is observed to start at the rear transition region where the plug core connects the films. However, the critical pressure is observed to be dependent on not only the plug length but also the interfacial shape.

KSC-02pd1410

NASA Image and Video Library

2002-09-30

KENNEDY SPACE CENTER, FLA. - Jack Wilcox (at the microphone) answers questions from the media during a reunion with his rescuers at the Hangar AF docks, Cape Canaveral Air Force Station. At right is his wife, Patty. Wilcox reunited with the men aboard KSC's Freedom Star SRB retrieval ship that was in the vicinity when Wilcox suffered decompression sickness on a diving expedition 20 miles off shore in the Atlantic Ocean. When the Freedom Star team heard the call for help, they asked the Coast Guard if they could assist. The ship was out on a crane certification exercise and coincidentally had a diver medical technician and other divers training on the crane. The ship's divers were trained for the hyperbaric chamber on board. Upon reaching the Army dock, KSC Occupational Health physician Skip Beeler entered the chamber and continued the process of helping to stabilize Wilcox. After several hours in the chamber, Wilcox, who lives in Orlando, was airlifted to Florida Hospital Orlando.

Blood lactate changes in professional Indian divers under hyperbaric conditions

PubMed Central

Sikri, Gaurav; Singh, S.P.; Srinivasa, A.B.; Chaudhry, H.B.S.

2016-01-01

Background Hyperoxia due to hyperbaric conditions influences lactate metabolism. Previous studies on lactate levels in hyperbaric conditions have reported varied results depending on the depth of evaluation and breathing gas mixture used. Methods This study compared post-exercise blood lactate levels of Indian professional male divers (breathing ambient air under normobaric conditions) with their post-exercise blood lactate levels measured under simulated hyperbaric conditions. Result In the present study, blood lactate levels in divers were found to have decreased significantly during recovery phase of exercise in hyperbaric conditions of dry diving at 2.8 Atmospheres Absolute (ATA) as compared to normobaric conditions. A significant improvement was observed in physical performance in terms of HR max and duration of exercise. Conclusion This study revealed that hyperoxia due to moderate hyperbaric condition leads to improvement in lactate metabolism in muscles and organs (liver and heart) for its removal. PMID:26900221

2007 Stability, Security, Transition and Reconstruction Operations Conference

DTIC Science & Technology

2007-11-28

narcotics Foster sustainable economy U.S.PRT tasks Jalalabad June 2007 Who can respond to which challeges ? 2. Battlespace or Humanitarian Space...Education Integrated Interagency Stabilization and Reconstruction Training Plug and Play System Lessons Learned from the Field USAID NGOs World Bank ...World Bank , IMF? Expanding the Focus… At the US and NATO Strategic/Operational Level Enhanced/new structures and procedures to improve: Interaction

[Evidence of lacrimal plugs via high resolution ultrasound].

PubMed

Tost, Frank H W; Darman, Jacques

2003-07-01

The practical value of high-frequency ultrasound (transducer frequency of 20 MHz) for studying lacrimal plugs positioned into canaliculi was proved. Twelve patients with twenty intracanalicular plugs and two punctum plugs were examined via high-frequency B-scan ultrasonography using 20 MHz transducer (model I3 Sacramento, USA). Detection and localisation of the intracanalicular plugs was made by a 20 MHz sector scanner. The ultrasound examinations were performed 1 - 24 month after the placement of lacrimal plugs. After patient's head positioning, the high-frequency ultrasound investigation was done via immersion fluid (2 % methylcellulose). All patients with dry eye treated by lacrimal plug implant showed echographic structure in the lacrimal canaliculus. In transversal echograms it was possible to image both canaliculi together when the lids were half-closed. Contrary to the normal state, it was not necessary to inject viscous fluid into the canaliculus. High-resolution ultrasound was able to differentiate the normal canaliculus from the findings after plug placement. The echograms can vary from one plug type to another. Highly reflective structures were found after the placement of silicone intracanalicular plugs, e. g. HERRICK-Plug. In contrast, the ultrasonic image taken through acrylic polymer intracanalicular plugs showed homogeneous small reflective inner structure, e. g. SMART-Plug. However, smooth and flat acoustic interface between acrylic polymer plug and the lacrimal canaliculus produced strong echoes. 20 MHz ultrasound seems to be well suited for the detection and localisation of intracanalicular plugs. By use of 20 MHz ultrasound scans it is possible to get high-quality images of the intracanalicular plug and around lacrimal canaliculus. Compared with UBM, the depth of penetration is much higher with negligible resolution. On the whole, we believe that 20 MHz ultrasound can become a useful tool for evaluating the placement of intracanalicular plugs after insertion.

The HomePlanet project: a HAVi multi-media network over POF

NASA Astrophysics Data System (ADS)

Roycroft, Brendan; Corbett, Brian; Kelleher, Carmel; Lambkin, John; Bareel, Baudouin; Goudeau, Jacques; Skiczuk, Peter

2005-06-01

This project has developed a low cost in-home network compatible with network standard IEEE1394b. We have developed all components of the network, from the red resonant cavity LEDs and VCSELs as light sources, the driver circuitry, plastic optical fibres for transmission, up to the network management software. We demonstrate plug-and-play operation of S100 and S200 (125 and 250Mbps) data streams using 650nm RCLEDs, and S400 (500 Mbps) data streams using VCSELs. The network software incorporates Home Audio Video interoperability (HAVi), which allows any HAVi device to be hot-plugged into the network and be instantly recognised and controllable over the network.

Wavelength-addressed intra-board optical interconnection by plug-in alignment with a micro hole array

NASA Astrophysics Data System (ADS)

Nakama, Kenichi; Tokiwa, Yuu; Mikami, Osamu

2010-09-01

Intra-board interconnection between optical waveguide channels is suitable for assembling high-speed optoelectronic printed wiring boards (OE-PWB). Here, we propose a novel optical interconnection method combining techniques for both wavelength-based optical waveguide addressing and plug-in optical waveguide alignment with a micro-hole array (MHA). This array was fabricated by the mask transfer method. For waveguide addressing, we used a micro passive wavelength selector (MPWS) module, which is a type of Littrow mount monochromator consisting of an optical diffraction grating, a focusing lens, and the MHA. From the experimental results, we found that the wavelength addressing operation of the MPWS module was effective for intra-board optical interconnection.

Retail Buildings: Assessing and Reducing Plug and Process Loads in Retail Buildings (Fact Sheet)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

2013-04-01

Plug and process loads (PPLs) in commercial buildings account for almost 5% of U.S. primary energy consumption. Minimizing these loads is a primary challenge in the design and operation of an energy-efficient building. PPLs are not related to general lighting, heating, ventilation, cooling, and water heating, and typically do not provide comfort to the occupants. They use an increasingly large fraction of the building energy use pie because the number and variety of electrical devices have increased along with building system efficiency. Reducing PPLs is difficult because energy efficiency opportunities and the equipment needed to address PPL energy use inmore » retail spaces are poorly understood.« less

Space shuttle orbit maneuvering engine reusable thrust chamber. Task 13: Subscale helium ingestion and two dimensional heating test report

NASA Technical Reports Server (NTRS)

Tobin, R. D.

1974-01-01

Descriptions are given of the test hardware, facility, procedures, and results of electrically heated tube, channel and panel tests conducted to determine effects of helium ingestion, two dimensional conduction, and plugged coolant channels on operating limits of convectively cooled chambers typical of space shuttle orbit maneuvering engine designs. Helium ingestion in froth form, was studied in tubular and rectangular single channel test sections. Plugged channel simulation was investigated in a three channel panel. Burn-out limits (transition of film boiling) were studied in both single channel and panel test sections to determine 2-D conduction effects as compared to tubular test results.

46 CFR 58.25-5 - General.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., means a ball, plug, spool, or similar valve with a handle connected for quick manual operation. Followup... its associated electrical equipment, including motor controller, disconnect switch, and feeder circuit. (2) In the case of an electro-hydraulic steering gear, an electric motor, connected pump, and...

Epidemiology of National Collegiate Athletic Association men's and women's swimming and diving injuries from 2009/2010 to 2013/2014.

PubMed

Kerr, Zachary Y; Baugh, Christine M; Hibberd, Elizabeth E; Snook, Erin M; Hayden, Ross; Dompier, Thomas P

2015-04-01

Recent injury data for collegiate-level swimming and diving are limited. This study describes the epidemiology of men's and women's swimming and diving injuries reported by the National Collegiate Athletic Association (NCAA) Injury Surveillance Program (ISP) during the 2009/2010 to 2013/2014 academic years. Injuries and athlete-exposure (AE) data reported within 9 men's and 13 women's swimming and diving programmes were analysed. Injury rates, injury rate ratios (IRR), and injury proportions by body site, diagnosis and mechanism were reported with 95% CIs. The ISP captured 149 and 208 injuries for men's and women's swimming and diving, respectively, leading to injury rates of 1.54/1000 and 1.71/1000 AEs. Among females, divers had a higher injury rate (2.49/1000 AEs) than swimmers (1.63/1000 AEs; IRR=1.53; 95% CI 1.07 to 2.19). Injury rates for male divers (1.94/1000 AEs) and swimmers (1.48/1000 AEs) did not differ (IRR=1.33; 95% CI 0.85 to 2.31). Most injuries occurred to the shoulder, resulted in strains and were classified as overuse or non-contact. Female swimmers had a higher overuse injury rate (1.04/1000 AEs) than male swimmers (0.66/1000 AEs; IRR=1.58; 95% CI 1.14 to 2.19). Overuse injury rates for female divers (0.54/1000 AEs) and male divers (0.46/1000 AEs) did not differ (IRR=1.16; 95% CI 0.40 to 3.34). Injury rates in 2012/2013-2013/2014 were lower than those in 2009/2010-2011/2012 for women's swimming (IRR=0.70; 95% CI 0.52 to 0.95) and diving (IRR=0.56; 95% CI 0.30 to 1.08), respectively. No time trends existed for men's swimmers or divers. Shoulder, strain and overuse injuries were common in collegiate men's and women's swimming and diving. Female swimmers were more likely to suffer an overuse injury than male swimmers. In addition, divers may have higher injury rates than swimmers, although small reported numbers warrant additional research. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://group.bmj.com/group/rights-licensing/permissions.

To assess the efficacy of socket plug technique using platelet rich fibrin with or without the use of bone substitute in alveolar ridge preservation: a prospective randomised controlled study.

PubMed

Girish Kumar, N; Chaudhary, Rupanzal; Kumar, Ish; Arora, Srimathy S; Kumar, Nilesh; Singh, Hem

2018-06-01

The purpose of this study is to evaluate the efficacy of Platelet Rich Fibrin (PRF) as a socket plug with or without use of Plaster of Paris (POP) as bone substitute to preserve the alveolar ridge post-extraction. A prospective randomised single blind controlled study, was conducted for 18 months from November 2014 to May 2016 on 48 patients requiring extraction. All teeth were extracted atraumatically using periotomes and luxators without raising mucoperiosteal flap. Sockets were randomly allotted to groups A, B and C. Group A sockets were chosen as control, where figure of eight suture was placed. In group B sockets, PRF obtained by centrifugation was used as a socket plug and stabilised with figure of eight suture. Group C sockets were filled with POP and then covered with PRF. The socket was then closed with a figure of eight suture. Patients were informed of need for 6 months follow-up. Ninety sockets in 48 patients were subjected to our study. We found that results in the sockets where we have grafted POP showed better ridge preservation and post-operative comfort even though the difference in ridge resorption between the three groups was not statistically significant. Powered by Editorial Manager® and ProduXion Manager® from the Aries Systems Corporation. Atraumatic extraction may minimise the post-operative pain and discomfort to patient as well as the post-extraction alveolar height and width changes. The use of PRF and/or bone substitute even though clinically contributes to better post-operative healing and minimal loss of alveolar width and height, the values were not statistically significant.

Integrated core-log petrofacies analysis in the construction of a reservoir geomodel: A case study of a mature Mississippian carbonate reservoir using limited data

USGS Publications Warehouse

Bhattacharya, S.; Doveton, J.H.; Carr, T.R.; Guy, W.R.; Gerlach, P.M.

2005-01-01

Small independent operators produce most of the Mississippian carbonate fields in the United States mid-continent, where a lack of integrated characterization studies precludes maximization of hydrocarbon recovery. This study uses integrative techniques to leverage extant data in an Osagian and Meramecian (Mississippian) cherty carbonate reservoir in Kansas. Available data include petrophysical logs of varying vintages, limited number of cores, and production histories from each well. A consistent set of assumptions were used to extract well-level porosity and initial saturations, from logs of different types and vintages, to build a geomodel. Lacking regularly recorded well shut-in pressures, an iterative technique, based on material balance formulations, was used to estimate average reservoir-pressure decline that matched available drillstem test data and validated log-analysis assumptions. Core plugs representing the principal reservoir petrofacies provide critical inputs for characterization and simulation studies. However, assigning plugs among multiple reservoir petrofacies is difficult in complex (carbonate) reservoirs. In a bottom-up approach, raw capillary pressure (Pc) data were plotted on the Super-Pickett plot, and log- and core-derived saturation-height distributions were reconciled to group plugs by facies, to identify core plugs representative of the principal reservoir facies, and to discriminate facies in the logged interval. Pc data from representative core plugs were used for effective pay evaluation to estimate water cut from completions, in infill and producing wells, and guide-selective perforations for economic exploitation of mature fields. The results from this study were used to drill 22 infill wells. Techniques demonstrated here can be applied in other fields and reservoirs. Copyright ?? 2005. The American Association of Petroleum Geologists. All rights reserved.

The History and Implications of Design Standards for Underwater Breathing Apparatus - 1954 to 2015

DTIC Science & Technology

2015-02-11

respiratory loading using both simple models of fluid mechanics and experimental evidence. An understanding of the influence of both respiratory ventilatory... fluid dynamics of flow in divers’ airways. It allows testing laboratories to make maximum use of all of their testing data, and lo present that data in...tireless efforts of numerous military divers at Navy Experimental Diving Unit in Panama City, FL and Naval Medical Research Institute, Bethesda, MD

Central Nervous System Oxygen Toxicity in Closed-Circuit Scuba Divers

DTIC Science & Technology

1986-03-01

CENTRAL NERVOUS SYSTEM OXYGEN TOXICITY IN CLOSED -CIRCUIT SCUBA DIVERS III By F. K. Butler, Jr., LCDR, MC, USN NAVY EXPERIMENTAL DIVING UNIT DTIC...PANAMA CITY. FLORIDA 321407 IN. aLV OMW Vol NAVY EXPERIMENTAL DIVING UNIT REPORT NO. 5-86 CENTRAL NERVOUS SYSTEM OXYGEN TOXICITY IN CLOSED -CIRCUIT SCUBA...BUTLER, Jr. J . .d.M. HAMILTON LCDR, MC, USK CDR, MC, USK CDR, USKN Medical Research Officer Senior Medical Officer Comanding Officer UNCLASSIFIED 4

Decompression illness in divers treated in Auckland, New Zealand, 1996-2012.

PubMed

Haas, Rachel M; Hannam, Jacqueline A; Sames, Christopher; Schmidt, Robert; Tyson, Andrew; Francombe, Marion; Richardson, Drew; Mitchell, Simon J

2014-03-01

The treatment of divers for decompression illness (DCI) in Auckland, New Zealand, has not been described since 1996, and subsequent trends in patient numbers and demographics are unmeasured. This was a retrospective audit of DCI cases requiring recompression in Auckland between 01 January 1996 and 31 December 2012. Data describing patient demographics, dive characteristics, presentation of DCI and outcomes were extracted from case notes and facility databases. Trends in annual case numbers were evaluated using Spearman's correlation coefficients (ρ) and compared with trends in entry-level diver certifications. Trends in patient demographics and delay between diving and recompression were evaluated using regression analyses. There were 520 DCI cases. Annual caseload decreased over the study period (ρ = 0.813, P < 0.0001) as did entry level diving certifications in New Zealand (ρ = 0.962, P < 0.0001). Mean diver age was 33.6 (95% confidence limits (CI) 32.7 to 34.5) years and age increased (P < 0.0001) over the study period. Median (range) delay to recompression was 2.06 (95% CI 0.02 to 23.6) days, and delay declined over the study period (P = 0.005). Numbers of DCI cases recompressed in Auckland have declined significantly over the last 17 years. The most plausible explanation is declining diving activity but improvements in diving safety cannot be excluded. The delay between diving and recompression has reduced.

Essential Hypertension: Cardiovascular Response to Breath Hold Combined with Exercise.

PubMed

Hoffmann, U; Urban, P; Koschate, J; Drescher, U; Pfister, R; Michels, G

2015-07-01

Essential hypertension (EH) is a widespread disease and might be prevalent in apnea divers and master athletes. Little is known about the influence of EH and the antihypertensive drugs (AHD) on cardiovascular reactions to combined breath hold (BH) and exercise. In this pilot study, healthy divers (HCON) were compared with treated hypertensive divers with regard to heart rate (HR) and mean blood-pressure (MAP) responses to BH, exercise and the combination of both. Ten subjects with EH and ten healthy divers were tested. 3 different 20 s stimuli were applied: BH combined with 30 W or 150 W and 150 W without BH. The time-charts during the stress intervals and during recovery were compared. Subjects treated with an angiotensin-converting enzyme (ACE) inhibitor showed higher changes for MAP values if breath hold was performed. HR responses were obviously changed if a β-blocker was part of the medication. One subject showed extreme MAP responses to all stimuli and conspicuous HR if BH was involved. The modulation of HR-/MAP-response in EH subjects depends on the mechanisms of antihypertensive agents. The combination of an ACE inhibitor and a β-blocker may give the best protection. It is recommended to include short apnea tests in the fitness-to-dive examination to individually predict potential endangerment. © Georg Thieme Verlag KG Stuttgart · New York.

Day 3 on the USS Anchorage for the Recovery of Orion

NASA Image and Video Library

2014-12-03

On the third day of preparations for recovery of Orion after its splashdown in the Pacific Ocean, the well deck of the USS Anchorage has been filled with water and recovery hardware is in place. U.S. Navy divers have embarked from ship to practice recovery procedures in rigid hull inflatable boats and Zodiac boats. NASA, Lockheed Martin and U.S. Navy personnel are preparing for recovery of the crew module, forward bay cover and parachutes on its return from space and splashdown in the Pacific Ocean. The Ground Systems Development and Operations Program is leading the recovery efforts.

Seawater Hydraulics: Development and Evaluation of an Experimental Diver Tool System.

DTIC Science & Technology

1984-02-01

wrench was operated, it ran irregularly and with low power; third, the motor would not always tart when the valve was actuated . Investigation revealed...I’’r Iulticctlic.4X N (4M144 i , I1.401 . (L(It I A,-- II N1I I I \\k RI Cit I X I)H ( 4 Wit IN ( N I (41lnson. XXaisli,, iot , D)4 NI I M4 I lid. Ill...its primary distribution lists. SUBJECT CATEGORIES 28 ENERGY/POWER GENERATION 29 Thermal conservation (thermal engineering of buildings. HVAC I SHORE

An underwater work systems package. [remote handling

NASA Technical Reports Server (NTRS)

Estabrook, N. B.

1975-01-01

A modular unit which is adaptable to several existing deep sea submersibles was developed to extend their working abilities and acquire knowledge of components and techniques for working in the deep sea environment. This work systems package is composed of an aluminum pipe structure on which are mounted two six-function grabber arms, a seven function manipulator, tool suit, 1,000/lb. capacity winch, electrohydraulic power supply, electronics housing, lights, and television. The unit is designed to be operated by itself either remotely or with divers, attached to manned submersibles, or mounted on unmanned cable-controlled submersibles.

STS-26 MS Nelson during Crew escape system (CES) testing in JSC WETF Bldg 29

NASA Image and Video Library

1988-07-08

S88-42409 (20 July 1988) --- STS-26 Discovery, Orbiter Vehicle (OV) 103, Mission Specialist (MS) George D. Nelson participates in crew escape system (CES) testing in JSC Weightless Environment Training Facility (WETF) Bldg 29. Nelson, wearing the newly designed (navy blue) launch and entry suit (LES), floats in WETF pool with the aid of an underarm flotation device (modern version of Mas West floats). He awaits the assistance of SCUBA-equipped divers during a simulation of escape and rescue operations utilizing a new CES pole for emergency exit from the Space Shuttle.

Operation and testing of Mark 10 Mod 3 underwater breathing apparatus

NASA Technical Reports Server (NTRS)

Milwee, W. I., Jr.

1972-01-01

Performance tests on a closed circuit, mixed gas underwater breathing apparatus are reported. The equipment is designed to provide a minimum diving duration of four hours at 1500 ft below sea surface; it senses oxygen partial pressure in the breathing gas mix and controls oxygen content of the breathing gas within narrow limits about a preset value. The breathing circuit subsystem provides respirable gas to the diver and removes carbon dioxide and moisture from the expired gas. Test results indicate undesirable variations in oxygen partial pressure with oxygen addition and insufficient carbon dioxide absorption.

STS-26 MS Lounge floats in life raft during JSC WETF exercises

NASA Technical Reports Server (NTRS)

1988-01-01

STS-26 Discovery, Orbiter Vehicle (OV) 103, Mission Specialist (MS) John M. Lounge, wearing the newly designed launch and entry suit (LES), floats in single-occupant life raft in JSC Weightless Environment Training Facility (WETF) Bldg 29 pool. Lounge pulls cord on life raft and enlists the aid of a SCUBA-equipped diver. The simulation of the escape and rescue operations utilized the crew escape system (CES) pole method of egress from the Space Shuttle. Lounge is wearing gear like that each STS-26 crewmember and subsequent crews will carry onboard during launch.

STS-55 MS2 Precourt in life raft during egress exercises at JSC's WETF

NASA Technical Reports Server (NTRS)

1992-01-01

Using a small single person life raft, STS-55 Mission Specialist 2 (MS2) Charles J. Precourt floats in the pool located in JSC's Weightless Environment Training Facility (WETF) Bldg 29. Precourt, wearing a launch and entry suit (LES) and launch and entry helmet (LEH), operates the Space Shuttle Search and Rescue Satellite Aided Tracking (SARSAT) portable locating beacon (PLC) as SCUBA-equipped diver looks on. Precourt, along with other crewmembers, practiced launch emergency egress (bailout). STS-55 with the Spacelab Deutsche 2 (SL-D2) payload will fly aboard Columbia, Orbiter Vehicle (OV) 102, in 1993.

Strategy Planning Visualization Tool (SPVT) for the Air Operations Center (AOC). Volume 2: Information Operations (IO) Planning Enhancements

DTIC Science & Technology

2009-12-31

Status and Assessment data interfaces leverage the TBONE Services and data model. The services and supporting Java 2 Platform Enterprise Edition (J2EE...existing Java ™ and .Net developed “Fat Clients.” The IOPC-X design includes an Open Services Gateway Initiative (OSGi) compliant plug-in...J2EE Java 2 Platform Enterprise Edition JAOP Joint Air Operations Plan JAST JAOP AOD Status Tool JFACC Joint Forces Air Component Commander Data

Ferroresonant Flux-Coupled Battery Charger

NASA Technical Reports Server (NTRS)

Mclyman, C. W.

1986-01-01

Portable battery charger operates at about 20 kHz to take advantage of relatively low weight and low acoustical noise of ferroresonant circuits operating in this frequency range. Charger split into stationary unit connected to powerline and mobile unit connected to battery or other load. Power transferred to mobile unit by magnetic coupling between mating transformer halves. Advantage where sparking at electrical connection might pose explosion hazard or where operator disabled and cannot manipulate plug into wall outlet. Likely applications for charger include wheelchairs and robots.

Plug into a Network.

ERIC Educational Resources Information Center

Vander Linden, Doug; Clark, Larry

1994-01-01

Stand-alone, single-user software programs for classroom use can be prohibitively expensive, compared to information-sharing network systems. Based on a Kansas district's experience, this article explains three types of networks (device-sharing, operating-system-based, and client-server-based) and discusses network protocols, software choices,…

30 CFR 250.1616 - Supervision, surveillance, and training.

Code of Federal Regulations, 2013 CFR

2013-07-01

... 30 Mineral Resources 2 2013-07-01 2013-07-01 false Supervision, surveillance, and training. 250... Operations § 250.1616 Supervision, surveillance, and training. (a) The lessee shall provide onsite...-floor surveillance continuously, unless the well is secured with BOP's, bridge plugs, packers, or cement...

30 CFR 250.1616 - Supervision, surveillance, and training.

Code of Federal Regulations, 2011 CFR

2011-07-01

... 30 Mineral Resources 2 2011-07-01 2011-07-01 false Supervision, surveillance, and training. 250... Operations § 250.1616 Supervision, surveillance, and training. (a) The lessee shall provide onsite...-floor surveillance continuously, unless the well is secured with BOP's, bridge plugs, packers, or cement...

30 CFR 250.1616 - Supervision, surveillance, and training.

Code of Federal Regulations, 2012 CFR

2012-07-01

... 30 Mineral Resources 2 2012-07-01 2012-07-01 false Supervision, surveillance, and training. 250... Operations § 250.1616 Supervision, surveillance, and training. (a) The lessee shall provide onsite...-floor surveillance continuously, unless the well is secured with BOP's, bridge plugs, packers, or cement...

Online Oxide Contamination Measurement and Purification Demonstration

NASA Technical Reports Server (NTRS)

Bradley, D. E.; Godfroy, T. J.; Webster, K. L.; Garber, A. E.; Polzin, K. A.; Childers, D. J.

2011-01-01

Liquid metal sodium-potassium (NaK) has advantageous thermodynamic properties indicating its use as a fission reactor coolant for a surface (lunar, martian) power system. A major area of concern for fission reactor cooling systems is system corrosion due to oxygen contaminants at the high operating temperatures experienced. A small-scale, approximately 4-L capacity, simulated fission reactor cooling system employing NaK as a coolant was fabricated and tested with the goal of demonstrating a noninvasive oxygen detection and purification system. In order to generate prototypical conditions in the simulated cooling system, several system components were designed, fabricated, and tested. These major components were a fully-sealed, magnetically-coupled mechanical NaK pump, a graphite element heated reservoir, a plugging indicator system, and a cold trap. All system components were successfully demonstrated at a maximum system flow rate of approximately 150 cc/s at temperatures up to 550 C. Coolant purification was accomplished using a cold trap before and after plugging operations which showed a relative reduction in oxygen content.

Reducing Plug Loads in Office Spaces: Hawaii and Guam Energy Improvement Technology Demonstration Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Sheppy, M.; Metzger, I.; Cutler, D.

2014-01-01

As part of its overall strategy to meet its energy goals, the Naval Facilities Engineering Command (NAVFAC) partnered with the Department of Energy's National Renewable Energy Laboratory (NREL) to rapidly demonstrate and deploy cost-effective renewable energy and energy efficiency technologies. This project was one of several demonstrations of new or underutilized commercial energy technologies. The common goal was to demonstrate and measure the performance and economic benefit of the system while monitoring any ancillary impacts to related standards of service and operation and maintenance (O&M) practices. In short, demonstrations at naval facilities simultaneously evaluate the benefits and compatibility of themore » technology with the U.S. Department of Defense (DOD) mission, and with NAVFAC's design, construction, operations, and maintenance practices, in particular. This project demonstrated the performance of commercially available advanced power strips (APSs) for plug load energy reductions in building A4 at Joint Base Pearl Harbor-Hickam (JBPHH), Hawaii.« less

InGaN/GaN light-emitting diode having direct hole injection plugs and its high-current operation.

PubMed

Kim, Sungjoon; Cho, Seongjae; Jeong, Jaedeok; Kim, Sungjun; Hwang, Sungmin; Kim, Garam; Yoon, Sukho; Park, Byung-Gook

2017-03-20

The light-emitting diode (LED) with an improved hole injection and straightforward process integration is proposed. p-type GaN direct hole injection plugs (DHIPs) are formed on locally etched multiple-quantum wells (MQWs) by epitaxial lateral overgrowth (ELO) method. We confirm that the optical output power is increased up to 23.2% at an operating current density of 100 A/cm². Furthermore, in order to identify the origin of improvement in optical performance, the transient light decay time and light intensity distribution characteristics were analyzed on the DHIP LED devices. Through the calculation of the electroluminescence (EL) decay time, internal quantum efficiency (IQE) is extracted along with the recombination parameters, which reveals that the DHIPs have a significant effect on enhancement of radiative recombination and reduction of efficiency droop. Furthermore, the mapping PL reveals that the DHIP LED also has a potential to improve the light extraction efficiency by hexagonal pyramid shaped DHIPs.

Orthogonal optimization of a water hydraulic pilot-operated pressure-reducing valve

NASA Astrophysics Data System (ADS)

Mao, Xuyao; Wu, Chao; Li, Bin; Wu, Di

2017-12-01

In order to optimize the comprehensive characteristics of a water hydraulic pilot-operated pressure-reducing valve, numerical orthogonal experimental design was adopted. Six parameters of the valve, containing diameters of damping plugs, volume of spring chamber, half cone angle of main spool, half cone angle of pilot spool, mass of main spool and diameter of main spool, were selected as the orthogonal factors, and each factor has five different levels. An index of flowrate stability, pressure stability and pressure overstrike stability (iFPOS) was used to judge the merit of each orthogonal attempt. Embedded orthogonal process turned up and a final optimal combination of these parameters was obtained after totally 50 numerical orthogonal experiments. iFPOS could be low to a fairly low value which meant that the valve could have much better stabilities. During the optimization, it was also found the diameters of damping plugs and main spool played important roles in stability characteristics of the valve.

Patterns of surface burrow plugging in a colony of black-tailed prairie dogs occupied by black-footed ferrets

USGS Publications Warehouse

Eads, David E.; Biggins, Dean E.

2012-01-01

Black-tailed prairie dogs (Cynomys ludovicianus) can surface-plug openings to a burrow occupied by a black-footed ferret (Mustela nigripes). At a coarse scale, surface plugs are more common in colonies of prairie dogs occupied by ferrets than in colonies without ferrets. However, little is known about spatial and temporal patterns of surface plugging in a colony occupied by ferrets. In a 452-ha colony of black-tailed prairie dogs in South Dakota, we sampled burrow openings for surface plugs and related those data to locations of ferrets observed during spotlight surveys. Of 67,574 burrow openings in the colony between June and September 2007, 3.7% were plugged. In a colony-wide grid of 80 m × 80 m cells, the occurrence of surface plugging (≥1 opening plugged) was greater in cells used by ferrets (93.3% of cells) than in cells not observably used by ferrets (70.6%). Rates of surface plugging (percentages of openings plugged) were significantly higher in cells used by ferrets (median = 3.7%) than in cells without known ferret use (median = 3.2%). Also, numbers of ferret locations in cells correlated positively with numbers of mapped surface plugs in the cells. To investigate surface plugging at finer temporal and spatial scales, we compared rates of surface plugging in 20-m-radius circle-plots centered on ferret locations and in random plots 1–4 days after observing a ferret (Jun–Oct 2007 and 2008). Rates of surface plugging were greater in ferret-plots (median = 12.0%) than in random plots (median = 0%). For prairie dogs and their associates, the implications of surface plugging could be numerous. For instance, ferrets must dig to exit or enter plugged burrows (suggesting energetic costs), and surface plugs might influence microclimates in burrows and consequently influence species that cannot excavate soil (e.g., fleas that transmit the plague bacterium Yersinia pestis).

Concierge: Personal Database Software for Managing Digital Research Resources

PubMed Central

Sakai, Hiroyuki; Aoyama, Toshihiro; Yamaji, Kazutsuna; Usui, Shiro

2007-01-01

This article introduces a desktop application, named Concierge, for managing personal digital research resources. Using simple operations, it enables storage of various types of files and indexes them based on content descriptions. A key feature of the software is a high level of extensibility. By installing optional plug-ins, users can customize and extend the usability of the software based on their needs. In this paper, we also introduce a few optional plug-ins: literature management, electronic laboratory notebook, and XooNlps client plug-ins. XooNIps is a content management system developed to share digital research resources among neuroscience communities. It has been adopted as the standard database system in Japanese neuroinformatics projects. Concierge, therefore, offers comprehensive support from management of personal digital research resources to their sharing in open-access neuroinformatics databases such as XooNIps. This interaction between personal and open-access neuroinformatics databases is expected to enhance the dissemination of digital research resources. Concierge is developed as an open source project; Mac OS X and Windows XP versions have been released at the official site (http://concierge.sourceforge.jp). PMID:18974800

Can citizen science contribute to fish assemblages monitoring in understudied areas? The case study of Tunisian marine protected areas

NASA Astrophysics Data System (ADS)

Ben Lamine, Emna; Di Franco, Antonio; Romdhane, Mohamed Salah; Francour, Patrice

2018-01-01

Resource monitoring is a key issue in ecosystem management especially for marine protected areas (MPAs), where information on the composition and structure of fish assemblages is crucial to design a sound management plan. Data on fish assemblage are usually collected using Underwater Visual Censuses (UVC). However, fish assemblages monitoring in MPAs usually calls for considerable resources in terms of costs, time and technical/scientific skills. Financial resources and trained scientific divers may, however, not be available in certain geographical areas, that are thus understudied. Therefore, involving citizen volunteer divers in fish assemblage monitoring and adopting easy-to-use underwater visual census methods could be an effective way to collect crucial data. Citizen science can be used only if it can provide information that is consistent with that collected using standard scientific monitoring. Here, we aim to: 1) compare the consistency of results from a Standard scientific UVC (S-UVC) and an Easy-to-use UVC (E-UVC) method in assessing fish assemblage spatial variability, and 2) test the consistency of data collected by Scientific Divers (SD) and Scientifically-Trained Volunteer divers (STV), using E-UVC. We used, in two consecutive years, three Tunisian future Marine Protected Areas (MPAs) and adjacent areas as case studies. E-UVC and S-UVC data were consistent in highlighting the same spatial patterns for the three MPAs (between MPAs and, inside and outside each one). No significant difference was recorded between data collected by SD or STV. Our results suggest that E-UVC can provide information representing simplified proxies for describing fish assemblages and can therefore be a valuable tool for fish monitoring by citizen divers in understudied areas. This evidence could foster citizen science as an effective tool to raise environmental awareness and involve stakeholders in resource management.

Epidemiology of National Collegiate Athletic Association men’s and women’s swimming and diving injuries from 2009/10 to 2013/14

PubMed Central

Kerr, Zachary Y.; Baugh, Christine M.; Hibberd, Elizabeth E.; Snook, Erin M.; Hayden, Ross; Dompier, Thomas P.

2015-01-01

Background/Aim Recent injury data for collegiate-level swimming and diving is limited. Previous data is limited to single seasons, elite and national team athletes, or emergency department data. This study describes the epidemiology of men’s and women’s swimming and diving injuries reported by the National Collegiate Athletic Association (NCAA) Injury Surveillance Program (ISP) during the 2009/10-2013/14 academic years. Methods Injuries and athlete-exposure (AE) data reported within nine men’s and 13 women’s swimming and diving programs were analyzed. Injury rates, injury rate ratios (IRR), and injury proportions by body site, diagnosis, and mechanism were reported with 95% confidence intervals (CI). Results The ISP captured 149 and 208 injuries for men’s and women’s swimming and diving, respectively, leading to injury rates of 1.54/1000AEs and 1.71/1000AEs. Among females, divers had a higher injury rate (2.49/1000AEs) than swimmers (1.63/1000AEs; IRR=1.53; 95%CI: 1.07, 2.19). Injury rates for male divers (1.94/1000AEs) and swimmers (1.48/1000AEs) did not differ (IRR=1.33; 95%CI: 0.85, 2.31). Most injuries occurred to the shoulder and resulted in strains. Many injuries were classified as overuse or non-contact. Female swimmers had a higher overuse injury rate (1.04/1000AEs) than male swimmers (0.66/1000AEs; IRR=1.58; 95%CI: 1.14, 2.19). Overuse injury rates for female divers (0.54/1000AEs) and male divers (0.46/1000AEs) did not differ (IRR=1.16; 95%CI: 0.40, 3.34). Conclusions Shoulder, strain, and overuse injuries were common in collegiate men’s and women’s swimming and diving. In addition, divers may have higher injury rates than swimmers, although small reported numbers in this study warrant additional research. PMID:25633831

Intraoperative visualization and assessment of electromagnetic tracking error

NASA Astrophysics Data System (ADS)

Harish, Vinyas; Ungi, Tamas; Lasso, Andras; MacDonald, Andrew; Nanji, Sulaiman; Fichtinger, Gabor

2015-03-01

Electromagnetic tracking allows for increased flexibility in designing image-guided interventions, however it is well understood that electromagnetic tracking is prone to error. Visualization and assessment of the tracking error should take place in the operating room with minimal interference with the clinical procedure. The goal was to achieve this ideal in an open-source software implementation in a plug and play manner, without requiring programming from the user. We use optical tracking as a ground truth. An electromagnetic sensor and optical markers are mounted onto a stylus device, pivot calibrated for both trackers. Electromagnetic tracking error is defined as difference of tool tip position between electromagnetic and optical readings. Multiple measurements are interpolated into the thin-plate B-spline transform visualized in real time using 3D Slicer. All tracked devices are used in a plug and play manner through the open-source SlicerIGT and PLUS extensions of the 3D Slicer platform. Tracking error was measured multiple times to assess reproducibility of the method, both with and without placing ferromagnetic objects in the workspace. Results from exhaustive grid sampling and freehand sampling were similar, indicating that a quick freehand sampling is sufficient to detect unexpected or excessive field distortion in the operating room. The software is available as a plug-in for the 3D Slicer platforms. Results demonstrate potential for visualizing electromagnetic tracking error in real time for intraoperative environments in feasibility clinical trials in image-guided interventions.

Friction pull plug welding: top hat plug design

NASA Technical Reports Server (NTRS)

Coletta, Edmond R. (Inventor); Cantrell, Mark A. (Inventor)

2001-01-01

Friction Pull Plug Welding is a solid state repair process for defects up to one inch in length, only requiring single sided tooling, or outside skin line (OSL), for preferred usage on flight hardware. The most prevalent defect associated with Friction Pull Plug Welding (FPPW) was a top side or inside skin line (ISL) lack of bonding. Bonding was not achieved at this location due to the reduction in both frictional heat and welding pressure between the plug and plate at the end of the weld. Thus, in order to eliminate the weld defects and increase the plug strength at the plug `top` a small `hat` section is added to the pull plug for added frictional heating and pressure.

Friction pull plug welding: top hat plug design

NASA Technical Reports Server (NTRS)

Coletta, Edmond R. (Inventor); Cantrell, Mark A. (Inventor)

2002-01-01

Friction Pull Plug Welding is a solid state repair process for defects up to one inch in length, only requiring single sided tooling, or outside skin line (OSL), for preferred usage on flight hardware. The most prevalent defect associated with Friction Pull Plug Welding (FPPW) was a top side or inside skin line (ISL) lack of bonding. Bonding was not achieved at this location due to the reduction in both frictional heat and welding pressure between the plug and plate at the end of the weld. Thus, in order to eliminate the weld defects and increase the plug strength at the plug `top` a small `hat` section is added to the pull plug for added frictional heating and pressure.

Comparative performance of fixed-film biological filters: Application of reactor theory

USGS Publications Warehouse

Watten, B.J.; Sibrell, P.L.

2006-01-01

Nitrification is classified as a two-step consecutive reaction where R1 represents the rate of formation of the intermediate product NO2-N and R2 represents the rate of formation of the final product NO3-N. The relative rates of R1 and R2 are influenced by reactor type characterized hydraulically as plug-flow, plug-flow with dispersion and mixed-flow. We develop substrate conversion models for fixed-film biofilters operating in the first-order kinetic regime based on application of chemical reactor theory. Reactor type, inlet conditions and the biofilm kinetic constants Ki (h-1) are used to predict changes in NH4-N, NO2-N, NO3-N and BOD5. The inhibiting effects of the latter on R1 and R2 were established based on the ?? relation, e.g.:{A formula is presented}where BOD5,max is the concentration that causes nitrification to cease and N is a variable relating Ki to increasing BOD5. Conversion models were incorporated in spreadsheet programs that provided steady-state concentrations of nitrogen and BOD5 at several points in a recirculating aquaculture system operating with input values for fish feed rate, reactor volume, microscreen performance, make-up and recirculating flow rates. When rate constants are standardized, spreadsheet use demonstrates plug-flow reactors provide higher rates of R1 and R2 than mixed-flow reactors thereby reducing volume requirements for target concentrations of NH4-N and NO2-N. The benefit provided by the plug-flow reactor varies with hydraulic residence time t as well as the effective vessel dispersion number, D/??L. Both reactor types are capable of providing net increases in NO2-N during treatment but the rate of decrease in the mixed-flow case falls well behind that predicted for plug-flow operation. We show the potential for a positive net change in NO2-N increases with decreases in the dimensionless ratios K2, (R2 )/K1,( R1 ) and [NO2-N]/[NH4-N] and when the product K1, (R1) t provides low to moderate NH4-N conversions. Maintaining high levels of the latter reduces the effective reactor utilization rate (%) defined here as (RNavg/RNmax)100 where RNavg is the mean reactive nitrogen concentration ([NH4-N] + [NO2-N]) within the reactor, and RNmax represents the feed concentration of the same. Low utilization rates provide a hedge against unexpected increases in substrate loading and reduce water pumping requirements but force use of elevated reactor volumes. Further ?? effects on R1 and R2 can be reduced through use of a tanks-in-series versus a single mixed-flow reactor configuration and by improving the solids removal efficiency of microscreen treatment.

Aspergillus fumigatus colonization of punctal plugs.

PubMed

Tabbara, Khalid F

2007-01-01

Punctal plugs are used in patients with dry eye syndrome to preserve the tears. In this report, I present two cases of Aspergillus fumigatus colonization of punctal plugs. Observational series of two cases. Approval was obtained from the institutional review board. Two men aged 29 and 31 years developed black spots inside the hole of punctal plug, which looked like eyeliner deposits. The deposits inside the hole of the plug in each patient were removed and cultured. Cultures of the two punctal plugs black deposits grew A fumigatus. Bacterial cultures were negative. Colonization of the punctal plug hole with A fumigatus was observed in two cases. It is recommended that punctal plugs be removed in patients undergoing refractive or intraocular procedures or in patients who are receiving topical corticosteroids. Current punctal plugs should be redesigned to avoid the presence of an inserter hole.

Aseptic Bone Necrosis Among U.S. Navy Divers: Survey of 934 Nonrandomly Selected Personnel

DTIC Science & Technology

1977-06-01

Health, Education, and Welfare, Washington, D.C. Kawashima, M., T. Torisu, K. Hayashi, and Y. Kamo. 1974. Avascular bone necrosis in Japanese diving...5ÜL ^4- P=- 7 RESEM^a^ATORY SUBMARINE BASE, GROTON, CONN. REPORT NUMBER 854 ASEPTIC BONE NECROSIS AMONG U. S. NAVY DIVERS: Survey of 934...Approved for public release; distribution unlimited SUMMARY PAGE THE PROBLEM Aseptic boire~ necrosis tABN) has beelTknown toT5e~ associated with

Human/computer control of undersea teleoperators

NASA Technical Reports Server (NTRS)

Sheridan, T. B.; Verplank, W. L.; Brooks, T. L.

1978-01-01

The potential of supervisory controlled teleoperators for accomplishment of manipulation and sensory tasks in deep ocean environments is discussed. Teleoperators and supervisory control are defined, the current problems of human divers are reviewed, and some assertions are made about why supervisory control has potential use to replace and extend human diver capabilities. The relative roles of man and computer and the variables involved in man-computer interaction are next discussed. Finally, a detailed description of a supervisory controlled teleoperator system, SUPERMAN, is presented.

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

DTIC Science & Technology

2015-05-28

Diver Characteristics Appendix E Diving Schedule Appendix F Medical Incidents Appendix G UBA Gas Compositions iv ACKNOWLEDGEMENTS The...experimental dives (median = 3). The schedule of each diver’s participation in experimental dives is given in Appendix E . Divers were required to avoid any...divers’ participation on each test schedule is given in Appendix E . The numbers of completed man-dives on the two schedules are not multiples of the

New Technology Sparks Smoother Engines and Cleaner Air

NASA Technical Reports Server (NTRS)

2001-01-01

Automotive Resources, Inc. (ARI) has developed a new device for igniting fuel in engines-the SmartPlug.TM SmartPlug is a self-contained ignition system that may be retrofitted to existing spark-ignition and compression-ignition engines. The SmartPlug needs as little as six watts of power for warm-up, and requires no electricity at all when the engine is running. Unlike traditional spark plugs, once the SmartPlug ignites the engine, and the engine heats up, the power supply for the plug is no longer necessary. In the utility industry, SmartPlugs can be used in tractors, portable generators, compressors, and pumps. In addition to general-purpose applications, such as lawn mowers and chainsaws, SmartPlugs can also be used in the recreational, marine, aviation, and automotive industries. Unlike traditional ignition systems, the SmartPlug system requires no distributor, coil points, or moving parts. SmartPlugs are non-fouling, with a faster and cleaner burn than traditional spark plugs. They prevent detonation and are not sensitive to moisture, allowing them to be used on a variety of engines. Other advantages include no electrical noise, no high voltage, exceptionally high altitude capabilities, and better cold-start statistics than those of standard spark ignition systems. Future applications for the SmartPlug are being evaluated by manufacturers in the snowmobile industry.

40 CFR 146.91 - Reporting requirements.

Code of Federal Regulations, 2012 CFR

2012-07-01

... any event that exceeds operating parameters for annulus pressure or injection pressure specified in the permit; (4) A description of any event which triggers a shut-off device required pursuant to § 146... plugging reports, post-injection site care data, including, if appropriate, data and information used to...

EPA Hydraulic Fracturing Study Technical Workshop #2 March 10-11, 2011: Well Integrity Case Study by Lloyd H. Hetrick

EPA Pesticide Factsheets

This case study defines well integrity by the prevention of vertical migration of fluids to protect drinking water resources. A generic shale development well is presented, including design, construction, operational phase, and its plug and abandonment.

A dynamic plug flow reactor model for a vanadium redox flow battery cell

NASA Astrophysics Data System (ADS)

Li, Yifeng; Skyllas-Kazacos, Maria; Bao, Jie

2016-04-01

A dynamic plug flow reactor model for a single cell VRB system is developed based on material balance, and the Nernst equation is employed to calculate cell voltage with consideration of activation and concentration overpotentials. Simulation studies were conducted under various conditions to investigate the effects of several key operation variables including electrolyte flow rate, upper SOC limit and input current magnitude on the cell charging performance. The results show that all three variables have a great impact on performance, particularly on the possibility of gassing during charging at high SOCs or inadequate flow rates. Simulations were also carried out to study the effects of electrolyte imbalance during long term charging and discharging cycling. The results show the minimum electrolyte flow rate needed for operation within a particular SOC range in order to avoid gassing side reactions during charging. The model also allows scheduling of partial electrolyte remixing operations to restore capacity and also avoid possible gassing side reactions during charging. Simulation results also suggest the proper placement for cell voltage monitoring and highlight potential problems associated with setting the upper charging cut-off limit based on the inlet SOC calculated from the open-circuit cell voltage measurement.

Accelerating Acceptance of Fuel Cell Backup Power Systems - Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Petrecky, James; Ashley, Christopher

2014-07-21

Since 2001, Plug Power has installed more than 800 stationary fuel cell systems worldwide. Plug Power’s prime power systems have produced approximately 6.5 million kilowatt hours of electricity and have accumulated more than 2.5 million operating hours. Intermittent, or backup, power products have been deployed with telecommunications carriers and government and utility customers in North and South America, Europe, the United Kingdom, Japan and South Africa. Some of the largest material handling operations in North America are currently using the company’s motive power units in fuel cell-powered forklifts for their warehouses, distribution centers and manufacturing facilities. The low-temperature GenSys fuelmore » cell system provides remote, off-grid and primary power where grid power is unreliable or nonexistent. Built reliable and designed rugged, low- temperature GenSys delivers continuous or backup power through even the most extreme conditions. Coupled with high-efficiency ratings, low-temperature GenSys reduces operating costs making it an economical solution for prime power requirements. Currently, field trials at telecommunication and industrial sites across the globe are proving the advantages of fuel cells—lower maintenance, fuel costs and emissions, as well as longer life—compared with traditional internal combustion engines.« less

AVTA Federal Fleet PEV Readiness Data Logging and Characterization Study for NASA Stennis Space Center

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schey, Stephen; Francfort, Jim

Federal agencies are mandated to purchase alternative fuel vehicles, increase consumption of alternative fuels, and reduce petroleum consumption. Available plug-in electric vehicles (PEVs) provide an attractive option in the selection of alternative fuel vehicles. PEVs, which consist of both battery electric vehicles (BEVs) and plug-in hybrid electric vehicles (PHEVs), have significant advantages over internal combustion engine (ICE) vehicles in terms of energy efficiency, reduced petroleum consumption, and reduced production of greenhouse gas (GHG) emissions, and they provide performance benefits with quieter, smoother operation. This study intended to evaluate the extent to which NASA Stennis Space Center (Stennis) could convert partmore » or all of their fleet of vehicles from petroleum-fueled vehicles to PEVs.« less

Volumetric dispenser for small particles from plural sources

DOEpatents

Bradley, R.A.; Miller, W.H.; Sease, J.D.

1975-12-16

Apparatus is described for rapidly and accurately dispensing measured volumes of small particles from a supply hopper. The apparatus includes an adjustable, vertically oriented measuring tube and orifice member defining the volume to be dispensed, a ball plug valve for selectively closing the bottom end of the orifice member, and a compression valve for selectively closing the top end of the measuring tube. A supply hopper is disposed above and in gravity flow communication with the measuring tube. Properly sequenced opening and closing of the two valves provides accurate volumetric discharge through the ball plug valve. A dispensing system is described wherein several appropriately sized measuring tubes, orifice members, and associated valves are arranged to operate contemporaneously to facilitate blending of different particles.

Integration Issues of Cells into Battery Packs for Plug-in and Hybrid Electric Vehicles: Preprint

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pesaran, A. A.; Kim, G. H.; Keyser, M.

2009-05-01

The main barriers to increased market share of hybrid electric vehicles (HEVs) and commercialization of plug-in HEVs are the cost, safety, and life of lithium ion batteries. Significant effort is being directed to address these issues for lithium ion cells. However, even the best cells may not perform as well when integrated into packs for vehicles because of the environment in which vehicles operate. This paper discusses mechanical, electrical, and thermal integration issues and vehicle interface issues that could impact the cost, life, and safety of the system. It also compares the advantages and disadvantages of using many small cellsmore » versus a few large cells and using prismatic cells versus cylindrical cells.« less

A new ImageJ plug-in "ActogramJ" for chronobiological analyses.

PubMed

Schmid, Benjamin; Helfrich-Förster, Charlotte; Yoshii, Taishi

2011-10-01

While the rapid development of personal computers and high-throughput recording systems for circadian rhythms allow chronobiologists to produce huge amounts of data, the software to analyze them often lags behind. Here, we announce newly developed chronobiology software that is easy to use, compatible with many different systems, and freely available. Our system can perform the most frequently used analyses: actogram drawing, periodogram analysis, and waveform analysis. The software is distributed as a pure Java plug-in for ImageJ and so works on the 3 main operating systems: Linux, Macintosh, and Windows. We believe that this free software raises the speed of data analyses and makes studying chronobiology accessible to newcomers. © 2011 The Author(s)

Method of measuring material properties of rock in the wall of a borehole

DOEpatents

Overmier, David K.

1985-01-01

To measure the modulus of elasticity of the rock in the wall of a borehole, a plug is cut in the borehole wall. The plug, its base attached to the surrounding rock, acts as a short column in response to applied forces. A loading piston is applied to the top of the plug and compression of the plug is measured as load is increased. Measurement of piston load and plug longitudinal deformation are made to determine the elastic modulus of the plug material. Poisson's ratio can be determined by simultaneous measurements of longitudinal and lateral deformation of the plug in response to loading. To determine shear modulus, the top of the plug is twisted while measurements are taken of torsional deformation.

Method of measuring material properties of rock in the wall of a borehole

DOEpatents

Overmier, D.K.

1984-01-01

To measure the modulus of elasticity of the rock in the wall of a borehole, a plug is cut in the borehole wall. The plug, its base attached to the surrounding rock, acts as a short column in response to applied forces. A loading piston is applied to the top of the plug and compression of the plug is measured as load is increased. Measurements of piston load and plug longitudinal deformation are made to determine the elastic modulus of the plug material. Poisson's ratio can be determined by simultaneous measurements of longitudinal and lateral deformation of the plug in response to loading. To determine shear modulus, the top of the plug is twisted while measurements are taken of torsional deformation.

Final report: Initial ecosystem response of salt marshes to ditch plugging and pool creation: Experiments at Rachel Carson National Wildlife Refuge (Maine)

USGS Publications Warehouse

Adamowicz, S.C.; Roman, C.T.

2002-01-01

This study evaluates the response of three salt marshes, associated with the Rachel Carson National Wildlife Refuge (Maine), to the practice of ditch plugging. Drainage ditches, originally dug to drain the marsh for mosquito control or to facilitate salt hay farming, are plugged with marsh peat in an effort to impound water upstream of the plug, raise water table levels in the marsh, and increase surface water habitat. At two study sites, Moody Marsh and Granite Point Road Marsh, ditch plugs were installed in spring 2000. Monitoring of hydrology, vegetation, nekton and bird utilization, and marsh development processes was conducted in 1999, before ditch plugging, and then in 2000 and 2001 (all parameters except nekton), after ditch plugging. Each study site had a control marsh that was monitored simultaneously with the plugged marsh, and thus, we employed a BACI study design (before, after, control, impact). A third site, Marshall Point Road Marsh, was plugged in 1998. Monitoring of the plugged and control sites was conducted in 1999 and 2000, with limited monitoring in 2001, thus there was no ?before? plug monitoring. With ditch plugging, water table levels increased toward the marsh surface and the areal extent of standing water increased. Responding to a wetter substrate, a vegetation change from high marsh species (e.g., Spartina patens) to those more tolerant of flooded conditions (e.g., Spartina alterniflora) was noted at two of the three ditch plugged sites. Initial response of the nekton community (fishes and decapod crustaceans) was evaluated by monitoring utilization of salt marsh pools using a 1m2 enclosure trap. In general, nekton species richness, density, and community structure remained unchanged following ditch plugging at the Moody and Granite Point sites. At Marshall Point, species richness and density (number of individuals per m2) were significantly greater in the experimental plugged marsh than the control marsh (<2% of the control marsh was open water habitat vs. 11% of the plugged marsh). The response of birds, categorized as waterfowl & waterbirds, shorebirds & wading birds, gulls & terns, and miscellaneous (raptors, passerines, other), was variable. Following ditch plugging, bird species richness increased at the Granite Point site (1999 pre-plug = 15.4, 2000 post-plug = 26.2, 2001 post-plug = 38.7). Because of a low sample size at Moody Marsh, reliable statements on species richness cannot be made. Density of birds (no. of birds per ha) remained unchanged with ditch plugging at Granite Point Marsh, although there was a strong, but not statistically significant, trend toward increased density. This study only reports on initial responses of marsh functions to ditch plugging. Monitoring should continue at these sites, and perhaps at additional sites, for the next decade or so. A monitoring plan is recommended. Long-term monitoring will include evaluation of salt marsh development processes using SET (surface elevation table) methodology. There is concern, although not confirmed, that as ditch-plugged marshes become wetter and marsh grass production declines their ability to keep pace with sea level rise could be jeopardized. It is suggested that ditch plugging should be considered an experimental marsh management technique. Additional monitoring on the physical and habitat responses of ditch-plugged marshes is required, along with assessments of other techniques aimed at restoring open water habitat to the marsh surface.

Assessing the suitability of a remotely operated vehicle (ROV) to study the fish community associated with offshore gas platforms in the Ionian Sea: a comparative analysis with underwater visual censuses (UVCs)

NASA Astrophysics Data System (ADS)

Andaloro, Franco; Ferraro, Maria; Mostarda, Edoardo; Romeo, Teresa; Consoli, Pierpaolo

2013-06-01

The effectiveness of a remotely operated vehicle (ROV) to describe the fish communities of three gas platforms located offshore Crotone (Italy, Ionian Sea) was investigated by comparing its observations with underwater visual censuses (UVCs). The study was carried out at two depth layers (0-6 and 12-18 m). Moreover, the ROV was used to survey three deeper depth layers up to 76 m. Overall, the ROV surveys failed to give a truthful representation of the fish communities underestimating the number of species and their abundances as compared to UVCs. The main discrepancies in data regarded crypto-benthic and nekto-benthic species, whereas the ROV proved to be a suitable method to census low-mobile and abundant planktivorous species. The differences between the fish assemblage described by the ROV, with respect to the one depicted by UVC, should be considered in the light of the technical limits of the recording camera, whose resolution and field of vision is clearly lower than the diver's eye. In addition, video images did not allow for the acquisition of a correct estimate of the distance between the individuals and the platform structures. This led, almost certainly, to an under- or over-estimation of fish abundance as regards to the censused volume. In spite of this, as a result of its capacity to reach depths inaccessible to scuba divers and then to add complementary information, the ROV could be used jointly with UVCs, in studies having as their objective the description of the fish communities associated with offshore platforms.

KSC-02pd1405

NASA Image and Video Library

2002-09-30

KENNEDY SPACE CENTER, FLA. -- Jack Wilcox, right, returns to the ship that helped rescue him at sea Sept. 11. With him is his wife, Patty. Wilcox reunited with the men aboard KSC's Freedom Star SRB retrieval ship that was in the vicinity when Wilcox suffered decompression sickness on a diving expedition 20 miles off shore in the Atlantic Ocean. When the Freedom Star team heard the call for help, they asked the Coast Guard if they could assist. The ship was out on a crane certification exercise and coincidentally had a diver medical technician and other divers training on the crane. The ship's divers were trained for the hyperbaric chamber on board. Upon reaching the Army dock, KSC Occupational Health physician Skip Beeler entered the chamber and continued the process of helping to stabilize Wilcox. After several hours in the chamber, Wilcox, who lives in Orlando, was airlifted to Florida Hospital Orlando. The reunion was held at the Hangar AF docks on the Cape Canaveral Air Force Station.

KSC-02pd1409

NASA Image and Video Library

2002-09-30

KENNEDY SPACE CENTER, FLA. - KENNEDY SPACE CENTER, FLA. - Jack Wilcox answers questions from the media during a reunion at the Hangar AF docks, Cape Canaveral Air Force Station, with his rescuers. At right is his wife, Patty. Wilcox reunited with the men aboard KSC's Freedom Star SRB retrieval ship that was in the vicinity when Wilcox suffered decompression sickness on a diving expedition 20 miles off shore in the Atlantic Ocean. When the Freedom Star team heard the call for help, they asked the Coast Guard if they could assist. The ship was out on a crane certification exercise and coincidentally had a diver medical technician and other divers training on the crane. The ship's divers were trained for the hyperbaric chamber on board. Upon reaching the Army dock, KSC Occupational Health physician Skip Beeler entered the chamber and continued the process of helping to stabilize Wilcox. After several hours in the chamber, Wilcox, who lives in Orlando, was airlifted to Florida Hospital Orlando.

Metabolomic approach with LC-MS reveals significant effect of pressure on diver's plasma.

PubMed

Ciborowski, Michal; Javier Rupérez, F; Martínez-Alcázar, Ma Paz; Angulo, Santiago; Radziwon, Piotr; Olszanski, Romuald; Kloczko, Janusz; Barbas, Coral

2010-08-06

Professional and recreational diving are growing activities in modern life. Diving has been associated with increased prevalence of stroke, hypertension, asthma, diabetes, or bone necrosis. We evaluated the effect of increased pressure equivalent to diving at 30 and 60 m for 30 min in two groups of divers using an untargeted approach with LC-MS fingerprinting of plasma. We found over 100 metabolites to be altered in plasma post exposure and after the corresponding decompression procedures. Among them, a group of lysophosphatidylcholines and lysophosphatidylethanolamines were increased, including lysoplasmalogen, a thrombosis promoter, together with changes in metabolic rate-associated molecules such as acylcarnitines and hemolysis-related compounds. Moreover, three metabolites that could be associated to bone degradation show different intensities between experimental groups. Ultimately, this nontargeted, short-term study opens the possibility of discovering markers of long-term effect of pressure that could be employed in routine health control of divers and could facilitate the development of safer decompression procedures.

RELEVANCE OF WHOLE BODY VIBRATION EXERCISE IN SPORT: A SHORT REVIEW WITH SOCCER, DIVER AND COMBAT SPORT.

PubMed

Morel, Danielle Soares; Dionello, Carla da Fontoura; Moreira-Marconi, Eloá; Brandão-Sobrinho-Neto, Samuel; Paineiras-Domingos, Laisa Liane; Souza, Patrícia Lopes; Sá-Caputo, Danúbia da Cunha; Dias, Glenda; Figueiredo, Claudia; Carmo, Roberto Carlos Resende; Paiva, Patrícia de Castro; Sousa-Gonçalves, Cintia Renata; Kütter, Cristiane Ribeiro; Guedes-Aguiar, Eliane de Oliveira; Cloak, Ross; Bernardo-Filho, Mario

2017-01-01

Whole body vibration exercise (WBVE) has been used as a safe and accessible exercise and important reviews have been published about the use of this exercise to manage diseases and to improve physical conditions of athletes The aim of this paper is to highlight the relevance of WBVE to soccer players, divers and combat athletes. This study was made through a systematic review of publications involving WBVE and the selected sports in two databases (Pubmed and PEDRo). It were identified 10 studies involving WBVE and sports (6 of soccer, 2 of diving and 2 of sport combat) with 156 subjects (80 soccer players, 32 divers and 44 combat athletes), with age from 17 to 44 years old. The use of WBVE has proven to be a safe and useful strategy to improve the physical conditions of players of different sports. These findings may have clinical relevance and should be considered as a strategy to be used to try improve the physical conditions of players.

Provisional report on diving-related fatalities in Australian waters 2003.

PubMed

Walker, Douglas; Lippmann, John

2009-03-01

An individual case review of the diving-related deaths that were reported to have occurred in Australia in 2003 was conducted as part of the combined Project Stickybeak/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 are provided, as well as details from the post mortem examination, where available. In total there were 22 reported fatalities, 18 men and four women. Twelve deaths occurred while snorkelling and/or breath-hold diving, nine while scuba diving and one while using surface-supply breathing apparatus. Cardiac-related issues were thought to have contributed to the deaths of six snorkel divers (50%) and four scuba divers (44%) in this series. There were three deaths in breath-hold divers likely to have been associated with apnoeic hypoxia blackout. Inexperience, time away from diving and lack of common sense were features in several scuba deaths.

Provisional report on diving-related fatalities in Australian waters 2005.

PubMed

Walker, Douglas; Lippmann, John; Lawrence, Chris; Fock, Andrew; Wodak, Thomas; Jamieson, Scott

2010-09-01

An individual case review of diving-related deaths reported as occurring in Australia in 2005 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 24 reported fatalities, comprising four females and 20 males. Fourteen deaths occurred while snorkelling and/or breath-hold diving, nine while scuba diving, and one while using surface-supply breathing apparatus. Four deaths from large marine animal attacks were recorded. Once again, cardiac-related issues were thought to have contributed to some deaths: five snorkel divers and at least two but possibly up to four scuba divers. Three of the deaths in breath-hold divers were likely to have been associated with apnoeic hypoxia blackout. Pre-existing medical conditions, trauma from marine creatures and snorkelling or diving alone were features in several deaths in this series.

Underwater and hyperbaric medicine as a branch of occupational and environmental medicine.

PubMed

Lee, Young Il; Ye, Byeong Jin

2013-12-19

Exposure to the underwater environment for occupational or recreational purposes is increasing. As estimated, there are around 7 million divers active worldwide and 300,000 more divers in Korea. The underwater and hyperbaric environment presents a number of risks to the diver. Injuries from these hazards include barotrauma, decompression sickness, toxic effects of hyperbaric gases, drowning, hypothermia, and dangerous marine animals. For these reasons, primary care physicians should understand diving related injuries and assessment of fitness to dive. However, most Korean physicians are unfamiliar with underwater and hyperbaric medicine (UHM) in spite of scientific and practical values.From occupational and environmental medicine (OEM) specialist's perspective, we believe that UHM should be a branch of OEM because OEM is an area of medicine that deals with injuries caused by physical and biological hazards, clinical toxicology, occupational diseases, and assessment of fitness to work. To extend our knowledge about UHM, this article will review and update on UHM including barotrauma, decompression illness, toxicity of diving gases and fitness for diving.

Corneal sensitivity, ocular surface health and tear film stability after punctal plug therapy of aqueous deficient dry eye

PubMed Central

Said, Azza Mohamed Ahmed; Farag, Mona Elsayed; Abdulla, Tarek Mohamed; Ziko, Othman Ali Othman; Osman, Wesam Mohamed

2016-01-01

AIM To evaluate the effect of punctal occlusion using thermosensitive (smart plug) versus silicone plug for management of aqueous deficient dry eye on corneal sensitivity, ocular surface health and tear film stability. METHODS A comparative prospective interventional case study included 45 patients with bilateral severe form of aqueous deficient dry eye. In each patient, the smart plug was inserted in the lower punctum of the right eye which was considered as study group 1 and silicone plug was inserted in the lower punctum of the left eye of the same patient which was considered as study group 2. All patients were subjected to careful history taking and questionnaire for subjective assessment of severity of symptoms. Corneal sensitivity, corneal fluorescein, rose bengal staining, Schirmer's I test, tear film break up time and conjunctival impression cytology were performed pre and 1, 3 and 6mo post plug insertion. RESULTS A statistically significant improvement in subjective and objective manifestations occurred following treatment with both types of plugs (P<0.01). The thermosensitive plug caused significant overall improvement, decrease in frequency of application of tear substitutes and improvement of conjunctival impression cytology parameters in the inserted side (P<0.01). Canaliculitis was reported in two eyes (4.4%) following punctal occlusion using thermosensitive plug (study group 1). Spontaneous plug loss occurred in 21 eyes (46.6%) in the silicone plug group (study group 2). CONCLUSION Improvement of subjective and objective manifestations of aqueous deficient dry eye occurs following punctal plug occlusion. Thermosensitive plug has good patient's compliance with fewer complications and lower rates of loss compared to the silicone plug. PMID:27990362

Intergovernmental Advanced Stationary PEM Fuel Cell System Demonstration Final Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rich Chartrand

A program to complete the design, construction and demonstration of a PEMFC system fuelled by Ethanol, LPG or NG for telecom applications was initiated in October 2007. Early in the program the economics for Ethanol were shown to be unfeasible and permission was given by DOE to focus on LPG only. The design and construction of a prototype unit was completed in Jun 2009 using commercially available PEM FC stack from Ballard Power Systems. During the course of testing, the high pressure drop of the stack was shown to be problematic in terms of control and stability of the reformer.more » Also, due to the power requirements for air compression the overall efficiency of the system was shown to be lower than a similar system using internally developed low pressure drop FC stack. In Q3 2009, the decision was made to change to the Plug power stack and a second prototype was built and tested. Overall net efficiency was shown to be 31.5% at 3 kW output. Total output of the system is 6 kW. Using the new stack hardware, material cost reduction of 63% was achieved over the previous Alpha design. During a November 2009 review meeting Plug Power proposed and was granted permission, to demonstrate the new, commercial version of Plug Power's telecom system at CERL. As this product was also being tested as part of a DOE Topic 7A program, this part of the program was transferred to the Topic 7A program. In Q32008, the scope of work of this program was expanded to include a National Grid demonstration project of a micro-CHP system using hightemperature PEM technology. The Gensys Blue system was cleared for unattended operation, grid connection, and power generation in Aug 2009 at Union College in NY state. The system continues to operate providing power and heat to Beuth House. The system is being continually evaluated and improvements to hardware and controls will be implemented as more is learned about the system's operation. The program is instrumental in improving the efficiency and reducing costs of PEMFC based power systems using LPG fuel and continues to makes steps towards meeting DOE's targets. Plug Power would like to thank DOE for their support of this program.« less

30 CFR 18.6 - Applications.

Code of Federal Regulations, 2014 CFR

2014-07-01

... metal and not have a compartment exceeding ten (10) feet in length. Glass or polycarbonate materials... polycarbonate windows and lenses shall not exceed 115 °C (240 °F), in normal operation. Other non-metallic... metallic conduit are not permitted. (H) Unused lead entrances shall be closed with a metal plug that is...