WorldWideScience

Sample records for high-capacity firefighting foam-dispensing

  1. Refinement of Foam Backfill Technology for Expedient Airfield Damage Repair; Phase 2: Development of Prototype Foam Dispensing Equipment and Improved Tactics, Techniques and Procedures

    Science.gov (United States)

    2017-12-01

    ER D C TR -1 7- 14 U.S. Air Force Rapid Airfield Damage Repair Modernization Program Refinement of Foam Backfill Technology for...Backfill Technology for Expedient Airfield Damage Repair Phase II: Development of Prototype Foam Dispensing Equipment and Improved Tactics...procedures (TTPs) for rapid airfield damage repair (RADR) using foam backfill technology . Three different prototype foam dispensing systems were

  2. CSTI High Capacity Power

    International Nuclear Information System (INIS)

    Winter, J.M.

    1989-01-01

    The SP-100 program was established in 1983 by DOD, DOE, and NASA as a joint program to develop the technology necessary for space nuclear power systems for military and civil application. During FY-86 and 87, the NASA SP-100 Advanced Technology Program was devised to maintain the momentum of promising technology advancement efforts started during Phase 1 of SP-100 and to strengthen, in key areas, the chances for successful development and growth capability of space nuclear reactor power systems for future space applications. In FY-88, the Advanced Technology Program was incorporated into NASA's new Civil Space Technology Initiative (CSTI). The CSTI Program was established to provide the foundation for technology development in automation and robotics, information, propulsion, and power. The CSTI High Capacity Power Program builds on the technology efforts of the SP-100 program, incorporates the previous NASA SP-100 Advanced Technology project, and provides a bridge to NASA Project Pathfinder. The elements of CSTI High Capacity Power development include Conversion Systems, Thermal Management, Power Management, System Diagnostics, and Environmental Interactions. Technology advancement in all areas, including materials, is required to assure the high reliability and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall program will develop and demonstrate the technology base required to provide a wide range of modular power systems as well as allowing mission independence from solar and orbital attitude requirements. Several recent advancements in CSTI High Capacity power development will be discussed

  3. 1990s: High Capacity Backbones

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. 1990s: High Capacity Backbones. Backbone capacities increased from 2.5 Gb/s to 100s of Gb/s during the 1990's. Wavelength division multiplexing with 160 waves of 10 Gb/s was commercially available. Several high-capacity backbones built in the US and Europe.

  4. Biomonitoring in California Firefighters

    Science.gov (United States)

    Israel, Leslie; McNeel, Sandra; Voss, Robert; Wang, Miaomiao; Gajek, Ryszard; Park, June-Soo; Harwani, Suhash; Barley, Frank; She, Jianwen; Das, Rupali

    2015-01-01

    Objective: To assess California firefighters' blood concentrations of selected chemicals and compare with a representative US population. Methods: We report laboratory methods and analytic results for cadmium, lead, mercury, and manganese in whole blood and 12 serum perfluorinated chemicals in a sample of 101 Southern California firefighters. Results: Firefighters' blood metal concentrations were all similar to or lower than the National Health and Nutrition Examination Survey (NHANES) values, except for six participants whose mercury concentrations (range: 9.79 to 13.42 μg/L) were close to or higher than the NHANES reporting threshold of 10 μg/L. Perfluorodecanoic acid concentrations were elevated compared with NHANES and other firefighter studies. Conclusions: Perfluorodecanoic acid concentrations were three times higher in this firefighter group than in NHANES adult males. Firefighters may have unidentified sources of occupational exposure to perfluorinated chemicals. PMID:25563545

  5. Respiratory Symptoms in Firefighters

    NARCIS (Netherlands)

    Greven, Frans E.; Rooyackers, Jos M.; Kerstjens, Huib A. M.; Heederik, Dick J.

    Background The aim of the present study was to determine the prevalence and risk factors associated with respiratory symptoms in common firefighters in the Netherlands. Methods A total of 1,330 firefighters from the municipal fire brigades of three provinces of the Netherlands were included in the

  6. Future High Capacity Backbone Networks

    DEFF Research Database (Denmark)

    Wang, Jiayuan

    are proposed. The work focuses on energy efficient routing algorithms in a dynamic optical core network environment, with Generalized MultiProtocol Label Switching (GMPLS) as the control plane. Energy ef- ficient routing algorithms for energy savings and CO2 savings are proposed, and their performance...... aiming for reducing the dynamic part of the energy consumption of the network may increase the fixed part of the energy consumption meanwhile. In the second half of the thesis, the conflict between energy efficiency and Quality of Service (QoS) is addressed by introducing a novel software defined......This thesis - Future High Capacity Backbone Networks - deals with the energy efficiency problems associated with the development of future optical networks. In the first half of the thesis, novel approaches for using multiple/single alternative energy sources for improving energy efficiency...

  7. Cancer incidence among firefighters

    DEFF Research Database (Denmark)

    Pukkala, Eero; Martinsen, Jan Ivar; Weiderpass, Elisabete

    2014-01-01

    OBJECTIVES: Firefighters are potentially exposed to a wide range of known and suspected carcinogens through their work. The objectives of this study were to examine the patterns of cancer among Nordic firefighters, and to compare them with the results from previous studies. METHODS: Data for this......OBJECTIVES: Firefighters are potentially exposed to a wide range of known and suspected carcinogens through their work. The objectives of this study were to examine the patterns of cancer among Nordic firefighters, and to compare them with the results from previous studies. METHODS: Data...... for this study were drawn from a linkage between the census data for 15 million people from the five Nordic countries and their cancer registries for the period 1961-2005. SIR analyses were conducted with the cancer incidence rates for the entire national study populations used as reference rates. RESULTS......: A total of 16 422 male firefighters were included in the final cohort. A moderate excess risk was seen for all cancer sites combined, (SIR=1.06, 95% CI 1.02 to 1.11). There were statistically significant excesses in the age category of 30-49 years in prostate cancer (SIR=2.59, 95% CI 1.34 to 4...

  8. Firefighter Nozzle Reaction

    DEFF Research Database (Denmark)

    Chin, Selena K.; Sunderland, Peter B.; Jomaas, Grunde

    2017-01-01

    to anchor forces, the hose becomes straight. The nozzle reaction is found to equal the jet momentum flow rate, and it does not change when an elbow connects the hose to the nozzle. A forward force must be exerted by a firefighter or another anchor that matches the forward force that the jet would exert...... on a perpendicular wall. Three reaction expressions are derived, allowing it to be determined in terms of hose diameter, jet diameter, flow rate, and static pressure upstream of the nozzle. The nozzle reaction predictions used by the fire service are 56% to 90% of those obtained here for typical firefighting hand...

  9. CERN's first female firefighter

    CERN Multimedia

    Alizée Dauvergne

    2010-01-01

    Until recently, the women's changing room in the Fire Station, built in 2005, has always been empty. With the arrival of Séverine Peverelly, CERN's first female firefighter, it now has a purpose. Séverine Peverelly took up her post as a firefighter in April. Séverine, who comes from Gap in France, took up her post as a firefighter in the CERN fire brigade at the beginning of April. "We were looking for a new member," explains David Peyron, Head of the Fire and Rescue Service. It didn't matter if it was a man or a woman; we needed a firefighter with the right skills, and Séverine just happened to have them." With ten years experience working in French fire services, Séverine was looking for a new challenge. "What attracted me to CERN was the international dimension, because that creates additional challenges," she explains. And these can be considerable! For one thing, every country has its own way of worki...

  10. Firefighter Nozzle Reaction

    DEFF Research Database (Denmark)

    Chin, Selena K.; Sunderland, Peter B.; Jomaas, Grunde

    2017-01-01

    Nozzle reaction and hose tension are analyzed using conservation of fluid momentum and assuming steady, inviscid flow and a flexible hose in frictionless contact with the ground. An expression that is independent of the bend angle is derived for the hose tension. If this tension is exceeded owing...... to anchor forces, the hose becomes straight. The nozzle reaction is found to equal the jet momentum flow rate, and it does not change when an elbow connects the hose to the nozzle. A forward force must be exerted by a firefighter or another anchor that matches the forward force that the jet would exert...... on a perpendicular wall. Three reaction expressions are derived, allowing it to be determined in terms of hose diameter, jet diameter, flow rate, and static pressure upstream of the nozzle. The nozzle reaction predictions used by the fire service are 56% to 90% of those obtained here for typical firefighting hand...

  11. Preventing Firefighter Exposure Hazards

    Science.gov (United States)

    2017-09-01

    exposed to whenever they remove their self- contained breathing equipment at the scene of a fire. If the high percentage of synthetic materials used...from their self- contained portable breathing apparatus.56 In February 1991, three firefighters died at the Meridian high -rise fire in Philadelphia... AVAILABILITY STATEMENT Approved for public release. Distribution is unlimited. 12b. DISTRIBUTION CODE 13. ABSTRACT (maximum 200words) This thesis

  12. FIREGUIDE: Firefighter guide and tracker.

    Science.gov (United States)

    Gandhi, Siddhesh Rajan; Ganz, Aura; Mullett, G

    2010-01-01

    In this paper, we introduce an indoor location tracking and navigation system (FIREGUIDE) using Bluetooth and RFID technology. FIREGUIDE assists the firefighters to find the nearest exit location and presents the Incident Commander the current firefighter's location superimposed on a map of the building floor. We envision that the FIREGUIDE system will save significant number of fire fighters and victims' lives.

  13. High capacity photonic integrated switching circuits

    NARCIS (Netherlands)

    Albores Mejia, A.

    2011-01-01

    As the demand for high-capacity data transfer keeps increasing in high performance computing and in a broader range of system area networking environments; reconfiguring the strained networks at ever faster speeds with larger volumes of traffic has become a huge challenge. Formidable bottlenecks

  14. Halon firefighting agents

    International Nuclear Information System (INIS)

    Pope, P.R.; Dalzell, G.A.

    1991-01-01

    This paper examines the current state of the International agreements on the use of halons and the subsequent National and industry approaches to the subject. It examines the definition of Essential Use and gives particular examples to clarify its interpretation. Alternative methods of loss control are reviewed. It does not address alternative active firefighting agents but examines the need for protection in particular areas. It addresses reduction of the hazards and consequences so that the need for protection can be minimized. Practical measures to minimize the installed quantities of halon are described. This covers specifications for new, essential, systems and the short term reduction of inventories in existing systems. The causes of leakage and accidental releases are studied and preventive measures are proposed. The paper concludes with an overview of the current research into replacement agents and the future outlook

  15. High Capacity cylinder roller bearing; High Capacity Zylinderrollenlager. Ein vollrolliges Lager mit Kaefig

    Energy Technology Data Exchange (ETDEWEB)

    Reichert, J.; Baum, J. [SKF, Schweinfurt (Germany)

    2007-07-15

    The high capacity cylinder roller bearing is an example for continuous development of SKF products and does an effective contribution to increase operational safety and offers the possibility to reduce weight and compact design. (GL)

  16. Acute effects of firefighting on cardiac performance.

    Science.gov (United States)

    Fernhall, Bo; Fahs, Christopher A; Horn, Gavin; Rowland, Thomas; Smith, Denise

    2012-02-01

    This study examined standard echocardiographic measures of cardiac size and performance in response to a 3-h firefighting training exercise. Forty experienced male personnel completed a standardized 3 h live firefighting exercise. Before and after the firefighting activities, participants were weighed, height, heart rate, blood pressure and blood samples were obtained, and echocardiographic measurements were made. Firefighting produced significant decreases in left ventricular diastolic dimension, stroke volume, fractional shortening, and mitral E velocity, tachycardia, a rise in core temperature, and a reduction in calculated plasma volume. On tissue Doppler imaging, there were no changes in systolic contractile function, but a decreased lateral wall diastolic velocity was observed. These findings show that 3 h of live firefighting produced cardiac changes consistent with cardiac fatigue, coupled with a decrease in systemic arterial compliance. These data show that live firefighting produces significant cardiovascular changes and future work is needed to evaluate if these changes are related to the increase in cardiovascular risk during live firefighting.

  17. High-capacity neutron activation analysis facility

    International Nuclear Information System (INIS)

    Hochel, R.C.

    1979-01-01

    A high-capacity neutron activation analysis facility, the Reactor Activation Facility, was designed and built and has been in operation for about a year at one of the Savannah River Plant's production reactors. The facility determines uranium and about 19 other trace elements in hydrogeochemical samples collected in the National Uranium Resource Evaluation program. The facility has a demonstrated average analysis rate of over 10,000 samples per month, and a peak rate of over 16,000 samples per month. Uranium is determined by cyclic activation and delayed neutron counting of the U-235 fission products; other elements are determined from gamma-ray spectra recorded in subsequent irradiation, decay, and counting steps. The method relies on the absolute activation technique and is highly automated for round-the-clock unattended operation

  18. High Capacity Radio over Fiber Transmission Links

    DEFF Research Database (Denmark)

    Caballero Jambrina, Antonio

    . This achievement has satisfied the requirements on transmission robustness and high capacity of next generation hybrid optical fibre-wireless networks. One important contribution of this thesis is the novel concept of photonic downconversion with free-running pulsed laser source for phase modulated Radio-over-Fiber......This thesis expands the state-of-the-art on the detection of high speed wireless signals using optics. Signal detection at speeds over 1 Gbps at carrier Radio Frequency (RF) ranging from 5 GHz to 100 GHz have been achieved by applying novel concepts on optical digital coherent receivers......-wave frequencies at carrier frequencies exceeding 60 GHz, using photonic baseband technologies. For signal generation, high spectral-efficient optical modulation technologies are used together with optical heterodyning. In the detection side, the mm-wave signal is modulated in the optical domain and received using...

  19. High Capacity Hydrogen Storage on Nanoporous Biocarbon

    Science.gov (United States)

    Burress, Jacob; Wood, Mikael; Gordon, Michael; Parilla, Phillip; Benham, Michael; Wexler, Carlos; Hawthorne, Fred; Pfeifer, Peter

    2008-03-01

    The Alliance for Collaborative Research in Alternative Fuel Technology (http://all-craft.missouri.edu) has been optimizing nanoporous biocarbon for high capacity hydrogen storage. The hydrogen storage was measured gravimetrically and volumetrically (Sievert's apparatus). These measurements have been validated by NREL and Hiden Isochema. Sample S-33/k, our current best performer, stores 73-91 g H2/kg carbon at 77 K and 47 bar, and 1.0-1.6 g H2/kg carbon at 293 K and 47 bar. Hydrogen isotherms run by Hiden Isochema have given experimental binding energies of 8.8 kJ/mol compared to the binding energy of graphite of 5 kJ/mol. Results from a novel boron doping technique will also be presented. The benefits and validity of using boron-doping on carbon will also be discussed.

  20. High-capacity neutron activation analysis facility

    International Nuclear Information System (INIS)

    Hochel, R.C.; Bowman, W.W.; Zeh, C.W.

    1980-01-01

    A high-capacity neutron activation analysis facility, the Reactor Activation Facility, was designed and built and has been in operation for about a year at one of the Savannah River Plant's production reactors. The facility determines uranium and about 19 other elements in hydrogeochemical samples collected in the National Uranium Resource Evaluation program, which is sponsored and funded by the United States Department of Energy, Grand Junction Office. The facility has a demonstrated average analysis rate of over 10,000 samples per month, and a peak rate of over 16,000 samples per month. Uranium is determined by cyclic activation and delayed neutron counting of the U-235 fission products; other elements are determined from gamma-ray spectra recorded in subsequent irradiation, decay, and counting steps. The method relies on the absolute activation technique and is highly automated for round-the-clock unattended operation

  1. The NASA CSTI High Capacity Power Project

    International Nuclear Information System (INIS)

    Winter, J.; Dudenhoefer, J.; Juhasz, A.; Schwarze, G.; Patterson, R.; Ferguson, D.; Schmitz, P.; Vandersande, J.

    1992-01-01

    This paper describes the elements of NASA's CSTI High Capacity Power Project which include Systems Analysis, Stirling Power Conversion, Thermoelectric Power Conversion, Thermal Management, Power Management, Systems Diagnostics, Environmental Interactions, and Material/Structural Development. Technology advancement in all elements is required to provide the growth capability, high reliability and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall project will develop and demonstrate the technology base required to provide a wide range of modular power systems compatible with the SP-100 reactor which facilitates operation during lunar and planetary day/night cycles as well as allowing spacecraft operation at any attitude or distance from the sun. Significant accomplishments in all of the project elements will be presented, along with revised goals and project timeliness recently developed

  2. The NASA CSTI High Capacity Power Program

    International Nuclear Information System (INIS)

    Winter, J.M.

    1991-09-01

    The SP-100 program was established in 1983 by DOD, DOE, and NASA as a joint program to develop the technology necessary for space nuclear power systems for military and civil applications. During 1986 and 1987, the NASA Advanced Technology Program was responsible for maintaining the momentum of promising technology advancement efforts started during Phase 1 of SP-100 and to strengthen, in key areas, the chances for successful development and growth capability of space nuclear reactor power systems for future space applications. In 1988, the NASA Advanced Technology Program was incorporated into NASA's new Civil Space Technology Initiative (CSTI). The CSTI program was established to provide the foundation for technology development in automation and robotics, information, propulsion, and power. The CSTI High Capacity Power Program builds on the technology efforts of the SP-100 program, incorporates the previous NASA advanced technology project, and provides a bridge to the NASA exploration technology programs. The elements of CSTI high capacity power development include conversion systems: Stirling and thermoelectric, thermal management, power management, system diagnostics, and environmental interactions. Technology advancement in all areas, including materials, is required to provide the growth capability, high reliability, and 7 to 10 year lifetime demanded for future space nuclear power systems. The overall program will develop and demonstrate the technology base required to provide a wide range of modular power systems while minimizing the impact of day/night operations as well as attitudes and distance from the Sun. Significant accomplishments in all of the program elements will be discussed, along with revised goals and project timelines recently developed

  3. Building the UPPA high capacity tensiometer

    Directory of Open Access Journals (Sweden)

    Mendes Joao

    2016-01-01

    Full Text Available High capacity tensiometers (HCTs are sensors capable of directly measuring tensile pore water pressure (suction in soils. HCTs are typically composed of a casing that encapsulates a high air entry value ceramic filter, a water reservoir and a pressure sensing element. Since the creation of the first HCT by Ridley and Burland in 1993 at Imperial College London, HCTs have been almost exclusively built and used in academic research. The limited use in industrial applications can be explained by a lack of unsaturated soil mechanics knowledge among engineering practitioners but also by the technical difficulties associated to the direct measurement of tensile water pressures beyond the cavitation limit of -100kPa. In this paper, we present the recent design and manufacture of a new HCT at the Université de Pau et des Pays de l’Adour (UPPA in France. Different prototypes were tried by changing the main components of the device including the type of ceramic filter, pressure transducer and geometry of the external casing. In particular, two ceramic filters of distinct porosity, three pressure transducers with distinct materials/geometries and four casing designs were tested.

  4. High capacity getter pump for UHV operation

    International Nuclear Information System (INIS)

    Manini, P.; Marino, M.; Belloni, F.; Porro, M.

    1993-01-01

    UHV pumps based on non-evaporable getter coated strips find widespread use in particle accelerators, synchrotron radiation machines and nuclear fusion experimental devices. Depending on the geometric constraints, pressure operation conditions and the foreseen gas loads, optimized getter structures, such as modules and cartridges, can be designed and assembled into a high-efficiency pump. In the present paper, the design and performance of a newly conceived High Capacity Getter Pump (HCGP) based on sintered getter bodies, in the shape of blades instead of strips, is illustrated. The porosity and the specific surface area of the blades and their arrangement in the cartridge have been optimized to significantly increase sorption capacity at a given speed. These pumps are well suited for those applications where a very high gas load is expected during the machine operation. The sintered getter bodies increase surface area and capacity, requiring less frequent reactivation and facilitating greater overall life of the pump. A discussion of the experimental results in terms of sorption speed and capacity for various gases is presented

  5. Development of high-capacity antimatter storage

    International Nuclear Information System (INIS)

    Howe, Steven D.; Smith, Gerald A.

    2000-01-01

    Space is vast. Over the next few decades, humanity will strive to send probes farther and farther into space to establish long baselines for interferometry, to visit the Kuiper Belt, to identify the heliopause, or to map the Oort cloud. In order to solve many of the mysteries of the universe or to explore the solar system and beyond, one single technology must be developed--high performance propulsion. In essence, future missions to deep space will require specific impulses between 50,000 and 200,000 seconds and energy densities greater than 10 14 j/kg in order to accomplish the mission within the career lifetime of an individual, 40 years. Only two technologies available to mankind offer such performance--fusion and antimatter. Currently envisioned fusion systems are too massive. Alternatively, because of the high energy density, antimatter powered systems may be relatively compact. The single key technology that is required to enable the revolutionary concept of antimatter propulsion is safe, reliable, high-density storage. Under a grant from the NASA Institute of Advanced Concepts, we have identified two potential mechanisms that may enable high capacity antimatter storage systems to be built. We will describe planned experiments to verify the concepts. Development of a system capable of storing megajoules per gram will allow highly instrumented platforms to make fast missions to great distances. Such a development will open the universe to humanity

  6. Towards green high capacity optical networks

    Science.gov (United States)

    Glesk, I.; Mohd Warip, M. N.; Idris, S. K.; Osadola, T. B.; Andonovic, I.

    2011-09-01

    The demand for fast, secure, energy efficient high capacity networks is growing. It is fuelled by transmission bandwidth needs which will support among other things the rapid penetration of multimedia applications empowering smart consumer electronics and E-businesses. All the above trigger unparallel needs for networking solutions which must offer not only high-speed low-cost "on demand" mobile connectivity but should be ecologically friendly and have low carbon footprint. The first answer to address the bandwidth needs was deployment of fibre optic technologies into transport networks. After this it became quickly obvious that the inferior electronic bandwidth (if compared to optical fiber) will further keep its upper hand on maximum implementable serial data rates. A new solution was found by introducing parallelism into data transport in the form of Wavelength Division Multiplexing (WDM) which has helped dramatically to improve aggregate throughput of optical networks. However with these advancements a new bottleneck has emerged at fibre endpoints where data routers must process the incoming and outgoing traffic. Here, even with the massive and power hungry electronic parallelism routers today (still relying upon bandwidth limiting electronics) do not offer needed processing speeds networks demands. In this paper we will discuss some novel unconventional approaches to address network scalability leading to energy savings via advance optical signal processing. We will also investigate energy savings based on advanced network management through nodes hibernation proposed for Optical IP networks. The hibernation reduces the network overall power consumption by forming virtual network reconfigurations through selective nodes groupings and by links segmentations and partitionings.

  7. Firefighter Workplace Learning: An Exploratory Case Study

    Science.gov (United States)

    Tracey, Edward A.

    2014-01-01

    Despite there being a significant amount of research investigating workplace learning, research exploring firefighter workplace learning is almost nonexistent. The purpose of this qualitative multi-case study was to explore how firefighters conceptualize, report, and practice workplace learning. The researcher also investigated how firefighters…

  8. Pulmonary function in portuguese firefighters

    OpenAIRE

    A G Almeida; R Duarte; L Mieiro; A C Paiva; A M Rodrigues; M H Almeida; C Bárbara

    2007-01-01

    Introduction: Portugal has had a high rate of forest fires in recent years. Inhaled wood smoke can have short- and long-term effects on the lung function of people exposed to it. Study objectives: To assess the lung function of active wildland (forest) firefighters. Methods: Cross-sectional study. A self-questionnaire on personal and work habits was used and spirometry values were obtained using Piko-6® for a 209 people sample. Results: We found a high rate of smoking (42.9%) and an 11.8% pre...

  9. The development and application of high-capacity thickening techniques

    International Nuclear Information System (INIS)

    Ji Zhenwan; Song Yuejie

    1995-01-01

    On the basis of sedimentation theory and comparison between the high-capacity and conventional thickening techniques, the authors analyse the ways to increase capacity and to improve technological parameters of thickeners, describes the construction features, development, application, automatic control and test installations of high-capacity thickeners at home and abroad

  10. Autonomy and Firefighting: Perceived Competence and Stress.

    Science.gov (United States)

    Chiang, Evelyn S; Baley, John; Ponder, Joy; Padilla, Miguel A

    2016-12-01

    In workplace settings, autonomy is implicated in employee motivation as well as supervisor autonomy support. As a profession of risk, firefighters may experience greater levels of stress. A self-determination paradigm was applied to the firefighter workplace. Of particular interest were perceived competence (to perform job duties) and the experience of stress. Firefighters' levels of autonomous and controlled regulation were surveyed, along with their perceptions of the autonomy support of their immediate supervisor. Autonomous regulation was positively related to perceived competence, whereas controlled regulation was negatively related. Higher levels of controlled regulation were also connected with greater stress. In contrast, greater perceived autonomy support was associated with decreased stress. Both perceived competence and stress are related to firefighter motivation and autonomy support. Recommendations are offered to increase autonomy support by chief officers.

  11. Safety climate and firefighting: Focus group results.

    Science.gov (United States)

    DeJoy, David M; Smith, Todd D; Dyal, Mari-Amanda

    2017-09-01

    Firefighting is a hazardous occupation and there have been numerous calls for fundamental changes in how fire service organizations approach safety and balance safety with other operational priorities. These calls, however, have yielded little systematic research. As part of a larger project to develop and test a model of safety climate for the fire service, focus groups were used to identify potentially important dimensions of safety climate pertinent to firefighting. Analyses revealed nine overarching themes. Competency/professionalism, physical/psychological readiness, and that positive traits sometimes produce negative consequences were themes at the individual level; cohesion and supervisor leadership/support at the workgroup level; and politics/bureaucracy, resources, leadership, and hiring/promotion at the organizational level. A multi-level perspective seems appropriate for examining safety climate in firefighting. Safety climate in firefighting appears to be multi-dimensional and some dimensions prominent in the general safety climate literature also seem relevant to firefighting. These results also suggest that the fire service may be undergoing transitions encompassing mission, personnel, and its fundamental approach to safety and risk. These results help point the way to the development of safety climate measures specific to firefighting and to interventions for improving safety performance. Copyright © 2017 National Safety Council and Elsevier Ltd. All rights reserved.

  12. 20 CFR 404.1212 - Police officers and firefighters.

    Science.gov (United States)

    2010-04-01

    ... 20 Employees' Benefits 2 2010-04-01 2010-04-01 false Police officers and firefighters. 404.1212... May Be Covered § 404.1212 Police officers and firefighters. (a) General. For Social Security coverage purposes under section 218 of the Act, a police officer's or firefighter's position is any position so...

  13. High capacity anode materials for lithium ion batteries

    Science.gov (United States)

    Lopez, Herman A.; Anguchamy, Yogesh Kumar; Deng, Haixia; Han, Yongbon; Masarapu, Charan; Venkatachalam, Subramanian; Kumar, Suject

    2015-11-19

    High capacity silicon based anode active materials are described for lithium ion batteries. These materials are shown to be effective in combination with high capacity lithium rich cathode active materials. Supplemental lithium is shown to improve the cycling performance and reduce irreversible capacity loss for at least certain silicon based active materials. In particular silicon based active materials can be formed in composites with electrically conductive coatings, such as pyrolytic carbon coatings or metal coatings, and composites can also be formed with other electrically conductive carbon components, such as carbon nanofibers and carbon nanoparticles. Additional alloys with silicon are explored.

  14. Fitness for Work Evaluation of Firefighters in Tehran

    Directory of Open Access Journals (Sweden)

    Ramin Mehrdad

    2013-04-01

    Full Text Available Firefighting is extremely strenuous and physically demanding work and involves ability to cope with emergency life-or-death situations. Because of the high physical demands of firefighting, successful job performance and minimizing of morbidity and mortality depends on fitness for duty. The firefighting department of Tehran does not perform periodic medical assessment for firefighters. The aim of this study was to evaluate medical fitness among firefighters in Tehran. In this cross sectional study we examined 147 firefighters. Medical and occupational history obtained by interview, then we performed physical examination, blood tests, ECG, spirometry and audiometry. Then results compared with guidelines for firefighters in the USA, Australia and the United Kingdom. Seven percent of our participants had a kind of pulmonary dysfunction and 25% had some degrees of hearing loss. A considerable percent of them had modifiable coronary heart disease risk factors. Thirteen participitants were unfit for this job that among them; ten firefighters were unfit based on vision capability, one case due to hypertention and two cases because of pulmonary dysfunction. Because of hazardouse nature of firefighting; preplacement, periodic medical evaluations and assesment of fitness for firefighters in Iran is highly recommended. Establishment of fitness criteria for firefighters in Iran is necessery to perform assigned functions safely.

  15. Efforts to update firefighter safety zone guidelines

    Science.gov (United States)

    Bret Butler

    2009-01-01

    One of the most critical decisions made on wildland fires is the identification of suitable safety zones for firefighters during daily fire management operations. To be effective (timely, repeatable, and accurate), these decisions rely on good training and judgment, but also on clear, concise guidelines. This article is a summary of safety zone guidelines and the...

  16. Addressing firefighter safety around solar PV systems

    Energy Technology Data Exchange (ETDEWEB)

    Harris, B. [Sustainable Energy Technologies, Calgary, AB (Canada)

    2010-11-15

    The article discussed new considerations for installing photovoltaic (PV) systems that address the needs of fire service personnel. The presence of a PV system presents a multitude of dangers for firefighters, including electrical shock, the inhalation of toxic gases from being unable to cut a hole through the roof, falling debris and flying glass, and dead loading on a compromised structure and tripping on conduits. Mapping systems should be modified so that buildings with PV systems are identified for first responders, including firefighters who should learn that solar modules present an electrical hazard during the day but not at night; covering PV modules with foam or salvage covers may not shut the system down to a safe level; it takes a few moments for the power in PV modules to reduce to zero; and PV modules or conduit should never be cut, broke, chopped, or walked upon. The California Department of Forestry and Fire Protection recommends creating pathways and allowing easier access to the roof by setting the modules back from roof edges, creating a structurally sound pathway for firefighters to walk on and space to cut ventilation holes. However, the setback rule makes the economics of solar installation less viable for residential applications. The technological innovations aimed at addressing system safety all focus on limiting firefighter contact with live electrical components to within the extra-low-voltage (ELV) band. Some of the inverters on the market that support ELV system architecture were described. 1 fig.

  17. Recent findings relating to firefighter safety zones

    Science.gov (United States)

    Bret Butler; Russ Parsons; William Mell

    2015-01-01

    Designation of safety zones is a primary duty of all wildland firefighters. Unfortunately, information regarding what constitutes an adequate safety zone is inadequately defined. Measurements of energy release from wildland fires have been used to develop an empirically based safety zone guideline. The basis for this work is described here.

  18. Depression and heart rate variability in firefighters

    Directory of Open Access Journals (Sweden)

    Li-Mei Liao

    2014-07-01

    Full Text Available Introduction: Depression has been found to increase the risk of mortality in patients with coronary artery disease through a mechanism of changing cardiac autonomic tone which is reflected by alteration of heart rate variability indices. This study investigated whether such mechanism existed in firefighters who were at high risk of depression and sudden cardiac death. Methods and results: In total, 107 firefighters were recruited. All completed Beck Depression Inventory and underwent 24-h ambulatory electrocardiographic monitoring. The root-mean-square of successive differences, standard deviation of all normal-to-normal intervals index, and the percentage of differences between adjacent normal-to-normal intervals >50 ms were significantly lower in depressed than in non-depressed firefighters after controlling for hypertension, age, and body mass index (40.1 ± 18.8 vs 62.5 ± 77.4, p < 0.01; 63.0 ± 19.2 vs 72.1 ± 34.8, p < 0.01; 8.4 ± 7.2 vs 12.7 ± 10.9, p < 0.01, respectively. Conclusion: Decreased vagal tone is a possible mechanism linking depression and sudden cardiac death in firefighters.

  19. Firefighters' noise exposure: A literature review

    Directory of Open Access Journals (Sweden)

    Taxini, Carla Linhares

    2013-01-01

    Full Text Available Aim: To review the literature about the effects of environmental noise on the hearing ability of firefighters. Method: The PubMed and Scielo databases were searched and studies from 2002 to 2012 that included the keywords firefighters, noise, and hearing loss were identified. Initially, 24 studies were selected, but only 10 met the inclusion criteria of investigating the effects of occupational noise on firefighters. Results: Only 2 (20% studies quantified levels of sound pressure and performed audiological tests to identify associations with noise intensity and 3 (30% questionnaire-based studies reported that these professionals are more susceptible to hearing loss. Four (50% studies found that noise exposure damages the auditory system in this population. Discussion: These findings indicate that there is a necessity for preventive measures to be adopted by this population since it is considered to be at risk. Conclusion: In recent years, there have been few studies of firefighters' exposure to occupational noise, but our findings show the importance of new studies that include proper means of quantifying their exposure to noise in different work environments, in order to identify possible adverse conditions as well as to aid in the diagnosis of hearing loss.

  20. Recycling rice husks for high-capacity lithium battery anodes.

    Science.gov (United States)

    Jung, Dae Soo; Ryou, Myung-Hyun; Sung, Yong Joo; Park, Seung Bin; Choi, Jang Wook

    2013-07-23

    The rice husk is the outer covering of a rice kernel and protects the inner ingredients from external attack by insects and bacteria. To perform this function while ventilating air and moisture, rice plants have developed unique nanoporous silica layers in their husks through years of natural evolution. Despite the massive amount of annual production near 10(8) tons worldwide, so far rice husks have been recycled only for low-value agricultural items. In an effort to recycle rice husks for high-value applications, we convert the silica to silicon and use it for high-capacity lithium battery anodes. Taking advantage of the interconnected nanoporous structure naturally existing in rice husks, the converted silicon exhibits excellent electrochemical performance as a lithium battery anode, suggesting that rice husks can be a massive resource for use in high-capacity lithium battery negative electrodes.

  1. High-capacity nanocarbon anodes for lithium-ion batteries

    International Nuclear Information System (INIS)

    Zhang, Haitao; Sun, Xianzhong; Zhang, Xiong; Lin, He; Wang, Kai; Ma, Yanwei

    2015-01-01

    Highlights: • The nanocarbon anodes in lithium-ion batteries deliver a high capacity of ∼1100 mA h g −1 . • The nanocarbon anodes exhibit excellent cyclic stability. • A novel structure of carbon materials, hollow carbon nanoboxes, has potential application in lithium-ion batteries. - Abstract: High energy and power density of secondary cells like lithium-ion batteries become much more important in today’s society. However, lithium-ion battery anodes based on graphite material have theoretical capacity of 372 mA h g −1 and low charging-discharging rate. Here, we report that nanocarbons including mesoporous graphene (MPG), carbon tubular nanostructures (CTN), and hollow carbon nanoboxes (HCB) are good candidate for lithium-ion battery anodes. The nanocarbon anodes have high capacity of ∼1100, ∼600, and ∼500 mA h g −1 at 0.1 A g −1 for MPG, CTN, and HCB, respectively. The capacity of 181, 141, and 139 mA h g −1 at 4 A g −1 for MPG, CTN, and HCB anodes is retained. Besides, nanocarbon anodes show high cycling stability during 1000 cycles, indicating formation of a passivating layer—solid electrolyte interphase, which support long-term cycling. Nanocarbons, constructed with graphene layers which fulfill lithiation/delithiation process, high ratio of graphite edge structure, and high surface area which facilitates capacitive behavior, deliver high capacity and improved rate-capability

  2. Biomonitoring in California firefighters: metals and perfluorinated chemicals.

    Science.gov (United States)

    Dobraca, Dina; Israel, Leslie; McNeel, Sandra; Voss, Robert; Wang, Miaomiao; Gajek, Ryszard; Park, June-Soo; Harwani, Suhash; Barley, Frank; She, Jianwen; Das, Rupali

    2015-01-01

    To assess California firefighters' blood concentrations of selected chemicals and compare with a representative US population. We report laboratory methods and analytic results for cadmium, lead, mercury, and manganese in whole blood and 12 serum perfluorinated chemicals in a sample of 101 Southern California firefighters. Firefighters' blood metal concentrations were all similar to or lower than the National Health and Nutrition Examination Survey (NHANES) values, except for six participants whose mercury concentrations (range: 9.79 to 13.42 μg/L) were close to or higher than the NHANES reporting threshold of 10 μg/L. Perfluorodecanoic acid concentrations were elevated compared with NHANES and other firefighter studies. Perfluorodecanoic acid concentrations were three times higher in this firefighter group than in NHANES adult males. Firefighters may have unidentified sources of occupational exposure to perfluorinated chemicals.

  3. Colloidal silica films for high-capacity DNA arrays

    Science.gov (United States)

    Glazer, Marc Irving

    The human genome project has greatly expanded the amount of genetic information available to researchers, but before this vast new source of data can be fully utilized, techniques for rapid, large-scale analysis of DNA and RNA must continue to develop. DNA arrays have emerged as a powerful new technology for analyzing genomic samples in a highly parallel format. The detection sensitivity of these arrays is dependent on the quantity and density of immobilized probe molecules. We have investigated substrates with a porous, "three-dimensional" surface layer as a means of increasing the surface area available for the synthesis of oligonucleotide probes, thereby increasing the number of available probes and the amount of detectable bound target. Porous colloidal silica films were created by two techniques. In the first approach, films were deposited by spin-coating silica colloid suspensions onto flat glass substrates, with the pores being formed by the natural voids between the solid particles (typically 23nm pores, 35% porosity). In the second approach, latex particles were co-deposited with the silica and then pyrolyzed, creating films with larger pores (36 nm), higher porosity (65%), and higher surface area. For 0.3 mum films, enhancements of eight to ten-fold and 12- to 14-fold were achieved with the pure silica films and the films "templated" with polymer latex, respectively. In gene expression assays for up to 7,000 genes using complex biological samples, the high-capacity films provided enhanced signals and performed equivalently or better than planar glass on all other functional measures, confirming that colloidal silica films are a promising platform for high-capacity DNA arrays. We have also investigated the kinetics of hybridization on planar glass and high-capacity substrates. Adsorption on planar arrays is similar to ideal Langmuir-type adsorption, although with an "overshoot" at high solution concentration. Hybridization on high-capacity films is

  4. Cycloaddition in peptides for high-capacity optical storage

    DEFF Research Database (Denmark)

    Lohse, Brian; Berg, Rolf Henrik; Hvilsted, Søren

    2006-01-01

    Photodimerization of chromophores attached to a short peptide chain is investigated for high-capacity optical digital storage with UV lasers. The length and rigidity of the peptide chain assure an optimal distance and orientation of the chromophores for effective photodimerization. Using a theory...... developed by Tomlinson, the absorption cross section for the dimerization process in a uracil-ornithine-based hexamer is determined to be 9 x 10(-20) cm(2). A large change in the transmission due to irradiation in the UV area may make it possible to realize multilevel storage in a thin film of the peptides....

  5. Effect of Aspirin Supplementation on Hemodynamics in Older Firefighters.

    Science.gov (United States)

    Lane-Cordova, Abbi D; Ranadive, Sushant M; Yan, Huimin; Kappus, Rebecca M; Sun, Peng; Bunsawat, Kanokwan; Smith, Denise L; Horn, Gavin P; Ploutz-Snyder, Robert; Fernhall, B O

    2015-12-01

    Cardiovascular events are the leading cause of line-of-duty fatality for firefighters. Aspirin reduces the risk of cardiovascular events in men and may reduce fatalities in older (>40 yr) firefighters. We hypothesized that both chronic and acute aspirin supplementation would improve vascular function after live firefighting but that chronic supplementation would also improve resting hemodynamics. Twenty-four firefighters (40-60 yr) were randomly assigned to acute or chronic aspirin supplementation or placebo in a balanced, crossover design. Arterial stiffness, brachial and central blood pressures, as well as forearm vasodilatory capacity and blood flow were measured at rest and immediately after live firefighting. Total hyperemic blood flow (area under the curve (AUC)) was increased (P 0.05 for interaction). Arterial stiffness/central blood pressure increased (P < 0.04) with no effect of aspirin (from 0.0811 ± 0.001 to 0.0844 ± 0.003 m·s·mm⁻¹ Hg⁻¹ in aspirin condition versus 0.0802 ± 0.002 to 0.0858 ± 0.002 m·s⁻¹·mm Hg⁻¹ in placebo condition), whereas peripheral and central systolic and pulse pressures decreased after firefighting across conditions (P < 0.05). Live firefighting resulted in increased AUC and pressure-controlled arterial stiffness and decreased blood pressure in older firefighters, but aspirin supplementation did not affect macro- or microvascular responsiveness at rest or after firefighting.

  6. CERN firefighters win medals in New York

    CERN Multimedia

    Joannah Caborn Wengler

    2011-01-01

    This year CERN's firefighters have taken part for the first time in the World Police and Fire Games,held in New York at the end of August. After an intensive training programme and some glorious achievements, the members of the CERN Fire Brigade taking part in the event enthusiastically share their experience with us.   Tomi Salmi (left) and Toni Rasanen (next to him) with their medals. Everybody has heard of the Olympic Games, but did you know that every two years firefighters and police officers from around the world hold their own version, which is second in size only to the Olympics? Since the mid-1980s, the World Police and Fire Games have taken place on three different continents, making waves in the cities that have hosted them. This year, the CERN Fire Brigade was part of a 10-day sports extravaganza in the city that never sleeps. Five CERN firefighters, two from Britain and three from Finland, participated in the Games in their chosen disciplines of triple jump, open water ...

  7. Learning fire-fighting lessons after Chernobyl

    International Nuclear Information System (INIS)

    Anon.

    1990-01-01

    Fire protection measures in Soviet nuclear power plants were set out in November 1987, in the Nuclear Power Plant Design Fire Protection Standards (VSN 01-87, USSR Ministry of Atomic Energy). The most important of these measures are. Avoiding as far as possible the use of combustible materials in plant structures and equipment. Dividing buildings and areas into suitable fire-fighting zones. Ensuring reliable fire protection of the control and safety systems. Protecting technical personnel from the dangers of a fire while they are performing essential accident-repair work and facilitating evacuation procedures (providing at least two evacuation routes and exits, anti-smoke protection of evacuation routes and control panel areas etc). Installing automatic fire-extinguishing and fire alarm systems. Providing various stationary facilities and equipment to assist the use of mobile fire-fighting appliances. In addition, a special fire-fighting division is being set up in every nuclear power plant while the first unit is still being constructed. These divisions work in close co-operation with the technical personnel management of the plant and with the bodies responsible for monitoring nuclear safety. (author)

  8. Firefighting and mental health: Experiences of repeated exposure to trauma.

    Science.gov (United States)

    Jahnke, Sara A; Poston, Walker S Carlos; Haddock, Christopher K; Murphy, Beth

    2016-02-15

    Firefighters must be ready to respond to a broad range of emergencies every duty day. In the course of many of these emergencies, firefighters witness events which have the potential to induce emotional trauma, such as badly injured people, deceased children, and individuals who are highly distraught. Previous research suggests that repeated exposure to these traumas (RET) may have negative impacts on the emotional and mental health of fire service personnel. Research on the mental health of firefighters has been limited to small surveys reporting the prevalence of specific mental health problems such as depression and post-traumatic stress disorder among firefighters. Despite the likelihood that RET leads to negative outcomes in firefighters, data is lacking on how exposure impacts fire service personnel. The current study examines the experiences of firefighters related to RET. Using formative research methods, we examined the beliefs and experiences of firefighters and administrators from across the United States regarding the impact of RET on firefighter health. Study findings highlight the cumulative psychological toll of repeated exposure to traumatic events including desensitization, flashbacks, and irritability. Results of the current study suggest that RET is a significant concern for emergency responders that warrants additional research and attention. It is likely that the long term consequences of RET are closely intertwined with other mental health outcomes and general well-being of this important occupational group.

  9. The communicative construction of safety in wildland firefighting (Proceedings)

    Science.gov (United States)

    Jody Jahn

    2012-01-01

    This dissertation project used a two-study mixed methods approach, examining the communicative accomplishment of safety from two perspectives: high reliability organizing (Weick, Sutcliffe, & Obstfeld 1999), and safety climate (Zohar 1980). In Study One, 27 firefighters from two functionally similar wildland firefighting crews were interviewed about their crew-...

  10. EMPLOYING SENSOR NETWORK TO GUIDE FIREFIGHTERS IN DANGEROUS AREA

    DEFF Research Database (Denmark)

    Koohi, Hamidreza; Nadernejad, Ehsan; Fathi, Mahmoud

    2010-01-01

    In this paper, we intend to focus on the sensor network applications in firefighting. A distributed algorithm is developed for the sensor network to guide firefighters through a burning area. The sensor network models the danger of the area under coverage as obstacles, and has the property to adapt...... itself against possible changes. The protocol developed, will integrate the artificial potential field of the sensors with the information of the intended place of moving firefighter so that it guides the firefighter step by step through the sensor network by choosing the safest path in dangerous zones....... This protocol is simulated by Visual-Sense and the simulation results are available. Keyword: Firefighter, Sensor Network, Potential Field, Area’s Danger, Navigation...

  11. A Concept for Support of Firefighter Frontline Communication

    Directory of Open Access Journals (Sweden)

    Tobias Dyrks

    2013-04-01

    Full Text Available In an indoor firefighter mission, coordination and communication support are of the utmost importance. We present our experience from over five years of research with current firefighter support technology. In contrast to some large scale emergency response research, our work is focused on the frontline interaction between teams of firefighters and the incident commander on a single site. In this paper we investigate the flaws in firefighter communication systems. Frequent technical failures and the high cognitive costs incurred by communicating impede coordination. We then extract a list of requirements for an assistant emergency management technology from expert interviews. Thirdly, we provide a system concept and explore challenges for building a novel firefighter support system based on our previous work. The system has three key features: robust ad-hoc network, telemetry and text messaging, as well as implicit interaction. The result would provide a complementary mode of communication in addition to the current trunked radio.

  12. High-Capacity, High-Voltage Composite Oxide Cathode Materials

    Science.gov (United States)

    Hagh, Nader M.

    2015-01-01

    This SBIR project integrates theoretical and experimental work to enable a new generation of high-capacity, high-voltage cathode materials that will lead to high-performance, robust energy storage systems. At low operating temperatures, commercially available electrode materials for lithium-ion (Li-ion) batteries do not meet energy and power requirements for NASA's planned exploration activities. NEI Corporation, in partnership with the University of California, San Diego, has developed layered composite cathode materials that increase power and energy densities at temperatures as low as 0 degC and considerably reduce the overall volume and weight of battery packs. In Phase I of the project, through innovations in the structure and morphology of composite electrode particles, the partners successfully demonstrated an energy density exceeding 1,000 Wh/kg at 4 V at room temperature. In Phase II, the team enhanced the kinetics of Li-ion transport and electronic conductivity at 0 degC. An important feature of the composite cathode is that it has at least two components that are structurally integrated. The layered material is electrochemically inactive; however, upon structural integration with a spinel material, the layered material can be electrochemically activated and deliver a large amount of energy with stable cycling.

  13. Space qualification of high capacity grooved heat pipes

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, M; Mullender, B; Druart, J [SABCA, Societe Anomyme Belgel de Construction Aeronautique (Belgium); Supper, W; Beddows, A [ESTEC-The (Netherlands)

    1997-12-31

    Based on the thermal requirements of the future telecommunication satellites, the development of a High Capacity Grooved Heat Pipe (HPG), was contracted by ESA to SABCA leading to an aluminium extruded heat pipe (outer diameter of 25 mm) based on a multi re-entrant grooves design. After an intensive acceptance test campaign whose results showed a good confidence in the design and the fulfillment of the required specifications of heat transport and on tilt capability (experimental maximum heat transport capability of 1500 Watt metres for a vapour temperature of 20 deg C), similar heat pipes have been developed with various outer diameters (11 mm, 15 mm and 20 mm) and with various shapes (circular outer shapes, integrated saddles). Several of these heat pipes were tested during two parabolic flight campaigns, by varying the heat loads during the micro-gravity periods. This HGP heat pipe family is now being submitted to a space qualification program according to ESA standards (ESA PSS-49), both in straight and bent configuration. Within this qualification, the heat pipes are submitted to an extended test campaign including environmental (random/sinus vibration, constant acceleration) and thermal tests (thermal performance, thermal cycle, thermal soak, ageing). (authors) 9 refs.

  14. High-capacity aqueous zinc batteries using sustainable quinone electrodes

    Science.gov (United States)

    Zhao, Qing; Huang, Weiwei; Luo, Zhiqiang; Liu, Luojia; Lu, Yong; Li, Yixin; Li, Lin; Hu, Jinyan; Ma, Hua; Chen, Jun

    2018-01-01

    Quinones, which are ubiquitous in nature, can act as sustainable and green electrode materials but face dissolution in organic electrolytes, resulting in fast fading of capacity and short cycle life. We report that quinone electrodes, especially calix[4]quinone (C4Q) in rechargeable metal zinc batteries coupled with a cation-selective membrane using an aqueous electrolyte, exhibit a high capacity of 335 mA h g−1 with an energy efficiency of 93% at 20 mA g−1 and a long life of 1000 cycles with a capacity retention of 87% at 500 mA g−1. The pouch zinc batteries with a respective depth of discharge of 89% (C4Q) and 49% (zinc anode) can deliver an energy density of 220 Wh kg−1 by mass of both a C4Q cathode and a theoretical Zn anode. We also develop an electrostatic potential computing method to demonstrate that carbonyl groups are active centers of electrochemistry. Moreover, the structural evolution and dissolution behavior of active materials during discharge and charge processes are investigated by operando spectral techniques such as IR, Raman, and ultraviolet-visible spectroscopies. Our results show that batteries using quinone cathodes and metal anodes in aqueous electrolyte are reliable approaches for mass energy storage. PMID:29511734

  15. Space qualification of high capacity grooved heat pipes

    Energy Technology Data Exchange (ETDEWEB)

    Dubois, M.; Mullender, B.; Druart, J. [SABCA, Societe Anomyme Belgel de Construction Aeronautique (Belgium); Supper, W.; Beddows, A. [ESTEC-The (Netherlands)

    1996-12-31

    Based on the thermal requirements of the future telecommunication satellites, the development of a High Capacity Grooved Heat Pipe (HPG), was contracted by ESA to SABCA leading to an aluminium extruded heat pipe (outer diameter of 25 mm) based on a multi re-entrant grooves design. After an intensive acceptance test campaign whose results showed a good confidence in the design and the fulfillment of the required specifications of heat transport and on tilt capability (experimental maximum heat transport capability of 1500 Watt metres for a vapour temperature of 20 deg C), similar heat pipes have been developed with various outer diameters (11 mm, 15 mm and 20 mm) and with various shapes (circular outer shapes, integrated saddles). Several of these heat pipes were tested during two parabolic flight campaigns, by varying the heat loads during the micro-gravity periods. This HGP heat pipe family is now being submitted to a space qualification program according to ESA standards (ESA PSS-49), both in straight and bent configuration. Within this qualification, the heat pipes are submitted to an extended test campaign including environmental (random/sinus vibration, constant acceleration) and thermal tests (thermal performance, thermal cycle, thermal soak, ageing). (authors) 9 refs.

  16. High-Capacity Spacesuit Evaporator Absorber Radiator (SEAR)

    Science.gov (United States)

    Izenson, Michael G.; Chen, Weibo; Phillips, Scott; Chepko, Ariane; Bue, Grant; Quinn, Gregory

    2015-01-01

    Future human space exploration missions will require advanced life support technology that can operate across a wide range of applications and environments. Thermal control systems for space suits and spacecraft will need to meet critical requirements for water conservation and multifunctional operation. This paper describes a Space Evaporator Absorber Radiator (SEAR) that has been designed to meet performance requirements for future life support systems. A SEAR system comprises a lithium chloride absorber radiator (LCAR) for heat rejection coupled with a space water membrane evaporator (SWME) for heat acquisition. SEAR systems provide heat pumping to minimize radiator size, thermal storage to accommodate variable environmental conditions, and water absorption to minimize use of expendables. We have built and tested a flight-like, high-capacity LCAR, demonstrated its performance in thermal vacuum tests, and explored the feasibility of an ISS demonstration test of a SEAR system. The new LCAR design provides the same cooling capability as prior LCAR prototypes while enabling over 30% more heat absorbing capacity. Studies show that it should be feasible to demonstrate SEAR operation in flight by coupling with an existing EMU on the space station.

  17. Prevalence of Metabolic syndrome in Tabriz city firefighters

    Directory of Open Access Journals (Sweden)

    Mehrangiz Ebrahimi-Mameghani

    2011-09-01

    Full Text Available Background: Metabolic syndrome (Metsyn is closely associated with cardiovascular disease (CVD particularly in stressful jobs such as firefighting. As studies assessing prevalence of Metsyn among firefighters are rare, this study was aimed to assess prevalence of Metsyn, insulin resistance and LP(a level among firefighters in Tabriz city.Methods: 76 firefighters and 73 official staffs in Tabriz firefighting organization were compared for demographic characteristics, anthropometric and blood pressure level. Obesity was defined using three indexes including body mass index (BMI, waist circumference (WC and waist-to-hip ratio (WHR. Fasting serum was used for assessing lipid profile, LP(a and HOMA score. Metsyn was determined using international diabetes federation (IDF criteria.Results: Prevalence of obesity was more based on the waist circumference compared with other obesity indexes, 28.9 % and 35.6 % in firefighters and staffs, respectively. Around half of the cases and controls suffered from hypertension. Prevalence of Metsyn was found in 56/6 % of firefighters and 60/3% of staffs. The mean of LP(a and HOMA score in firefighters and staffs was 18.40 mg/dl and 1.17 vs. 18.15 mg/dl and 1.48, respectively. Neither LP(a (P=0.823 and HOMA score (P=0.668 nor biochemical parameters were statistically different between two groups.Conclusion: Obesity and Metsyn were common among firefighters and the staffs. Knowledge promotion focusing on lifestyle modification such as physical activity and healthy eating is suggested.

  18. Physical and thermal strain of firefighters according to the firefighting tactics used to suppress wildfires.

    Science.gov (United States)

    Rodríguez-Marroyo, J A; Villa, J G; López-Satue, J; Pernía, R; Carballo, B; García-López, J; Foster, C

    2011-11-01

    The aim of this study was to analyse the physiological strain of firefighters, using heart rate (HR) and core temperature, during real wildfire suppression according to the type of attack performed (direct, indirect or mixed). Three intensity zones were established according to the HR corresponding to the ventilatory threshold (VT) and respiratory compensation threshold (RCT): zone 1, RCT. The exercise workload (training impulse (TRIMP)), the physiological strain index (PSI) and the cumulative heat strain index(CHSI) were calculated using the time spent in each zone, and the HR and core temperature, respectively. Significantly higher mean HR, time spent in Z2 and Z3 and TRIMP h(-1) were found in direct and mixed versus indirect attacks. The highest PSI and CHSI were observed in the direct attack. In conclusion, exercise strain and combined thermal strain, but not core temperature during wildfire suppression, are related to the type of attack performed. STATEMENT OF RELEVANCE: Our findings demonstrated that wildfire firefighting is associated with high physiological demands, which vary significantly depending on the tactics chosen for performing the task. These results should be kept in mind when planning programmes to improve wildland firefighters' physical fitness, which will allow improvement in their performance.

  19. CERN firefighters have got your back covered

    CERN Multimedia

    The Fire Brigade

    2011-01-01

    There’s not much room in the centre of a detector. Ensuring the safety of technicians who have to work on components close to the collision point is an absolute priority. With this firmly in mind, the Fire Brigade has recently acquired a back immobilisation device known as a spine splint.   CERN firefighters show off their new spine splint. Conscious of the potential safety hazards for personnel working on ALICE’s inner detectors, the collaboration’s GLIMOS, Fernando Pedrosa, asked the Fire Brigade to organise an exercise in March to simulate the emergency evacuation of a person from the centre of the detector. Despite the exceptionally limited space available in the centre of ALICE, the Fire Brigade successfully met the challenge. However, although specially designed for emergency evacuations, the cumbersome dimensions of the stretcher used in this first exercise caused many problems.   Following the exercise, the Fire Brigade therefore inves...

  20. Lung function changes in wildland firefighters working at prescribed burns.

    Energy Technology Data Exchange (ETDEWEB)

    Adetona, Olorunfemi; Hall, Daniel, B.; Naeher, L,P.

    2011-10-01

    Although decline in lung function across workshift has been observed in wildland firefighters, measurements have been restricted to days when they worked at fires. Consequently, such results could have been confounded by normal circadian variation associated with lung function. We investigated the across-shift changes in lung function of wildland firefighters, and the effect of cumulative exposure on lung function during the burn season.

  1. The effect of terrain slope on firefighter safety zone effectiveness

    Science.gov (United States)

    Bret Butler; J. Forthofer; K. Shannon; D. Jimenez; D. Frankman

    2010-01-01

    The current safety zone guidelines used in the US were developed based on the assumption that the fire and safety zone were located on flat terrain. The minimum safe distance for a firefighter to be from a flame was calculated as that corresponding to a radiant incident energy flux level of 7.0kW-m-2. Current firefighter safety guidelines are based on the assumption...

  2. Estimation of Forest Fire-fighting Budgets Using Climate Indexes

    OpenAIRE

    Zhen Xu; G. Cornelis van Kooten

    2012-01-01

    Given the complexity and relative short length of current predicting system for fire behavior, it is inappropriate to be referred for planning fire-fighting budgets of BC government due to the severe uncertainty of fire behavior across fire seasons. Therefore, a simple weather derived index for predicting fire frequency and burned area is developed in this paper to investigate the potential feasibility to predict fire behavior and fire-fighting expenses for the upcoming fire season using clim...

  3. The Development and Design of a Prototype Ultra High Pressure P-19 Firefighting Vehicle

    National Research Council Canada - National Science Library

    Menchini, Christopher P; Dierdorf, Douglas; Kalberer, Jennifer L; McDonald, Michael J; Cozart, Kristofor S; Casarez, Adriana; Carr, Jr, Virgil J

    2007-01-01

    ...) and combined agent firefighting using compressed air foam (CAF) and dry chemical. The latest demonstrator uniquely incorporating both UHP and combined agent firefighting capability is a retrofitted P-19...

  4. High-capacity, selective solid sequestrants for innovative chemical separation: Inorganic ion exchange approach

    International Nuclear Information System (INIS)

    Bray, L.

    1995-01-01

    The approach of this task is to develop high-capacity, selective solid inorganic ion exchangers for the recovery of cesium and strontium from nuclear alkaline and acid wastes. To achieve this goal, Pacific Northwest Laboratories (PNL) is collaborating with industry and university participants to develop high capacity, selective, solid ion exchangers for the removal of specific contaminants from nuclear waste streams

  5. 46 CFR 167.45-30 - Use of approved fire-fighting equipment.

    Science.gov (United States)

    2010-10-01

    ... PUBLIC NAUTICAL SCHOOL SHIPS Special Firefighting and Fire Prevention Requirements § 167.45-30 Use of approved fire-fighting equipment. Portable fire extinguishers or fire-extinguishing systems which conform... 46 Shipping 7 2010-10-01 2010-10-01 false Use of approved fire-fighting equipment. 167.45-30...

  6. Firefighter Down! How to Rapidly Remove Turnout Gear.

    Science.gov (United States)

    ALexander, John G

    2016-04-01

    The rescue of an injured colleague--and probably a good friend--is an emotionally charged event. A common initial response could be to remove everything as quickly as possible. Keep in mind that we have accepted practices for the removal of motorcycle equipment and football gear. There are also procedures for removing a patient from a vehicle or swimming pool. These all exist to protect a patient from further injury. We now have established practices for removing a firefighter from a window, or down a ladder. Why then do the procedures stop? Once a firefighter is rescued from a hot zone, he deserves the same level of consideration a football player, motorcycle rider or any other patient receives. We should not be in such a hurry that we don't care how we remove a protective ensemble. The injured firefighter deserves a system, or a procedure, that may be practiced by others and reduce the chance of further injury during

  7. CERN’s firefighters hone their trauma response skills

    CERN Multimedia

    Anaïs Schaeffer

    2016-01-01

    Seven CERN firefighters have been trained in how to treat trauma victims. This training forms part of the Fire Brigade’s efforts to acquire specialist knowledge.   The fifteen trainees who took the PHTLS course at CERN, with the instructor team. On 23 and 24 May, the CERN Fire Brigade welcomed five instructors from Life Support France, an association that offers training in pre-hospital emergency treatment, to provide a course on Pre-Hospital Trauma Life Support (PHTLS). Fifteen “trainees” – seven CERN firefighters and eight rescue and healthcare professionals from outside the Organization (nurses, paramedics and firefighters) – took part in the course, at the end of which they were awarded an official PHTLS certificate, valid for four years. Of course, the whole PHTLS programme cannot be covered in just two days, so several months of additional work were required in advance of the course, particularly to acquire the necessary theoretical knowledg...

  8. Analysis of the risk of injury to firefighters based on a functional assessment using the Functional Movement Screen test

    Directory of Open Access Journals (Sweden)

    Krystian Kałużny

    2017-05-01

    Conclusions. 1. In examined firefighters, abnormalities in basic motor patterns are observed in the FMS test. 2. The risk of injury in FMS surveyed firefighters is very high. 3. The FMS test results correlate with BMI, work experience and age of firefighters. 4. No correlation was found between injuries and injuries and physical activity in firefighters and the FMS test result.

  9. Effect of heat on firefighters' work performance and physiology.

    Science.gov (United States)

    Larsen, Brianna; Snow, Rodney; Aisbett, Brad

    2015-10-01

    Wildland firefighters often perform their duties under both hot and mild ambient temperatures. However, the direct impact of different ambient temperatures on firefighters' work performance has not been quantified. This study compared firefighters' work performance and physiology during simulated wildland firefighting work in hot (HOT; 32°C, 43% RH) and temperate (CON; 19°C, 56% RH) conditions. Firefighters (n=38), matched and allocated to either the CON (n=18) or HOT (n=20) condition, performed simulated self-paced wildland fire suppression tasks (e.g., hose rolling/dragging, raking) in firefighting clothing for six hours, separated by dedicated rest breaks. Task repetitions were counted (and converted to distance or area). Core temperature (Tc), skin temperature (Tsk), and heart rate were recorded continuously throughout the protocol. Urine output was measured before and during the protocol, and urine specific gravity (USG) analysed, to estimate hydration. Ad libitum fluid intake was also recorded. There were no differences in overall work output between conditions for any physical task. Heart rate was higher in the HOT (55±2% HRmax) compared to the CON condition (51±2% HRmax) for the rest periods between bouts, and for the static hose hold task (69±3% HRmax versus 65±3% HRmax). Tc and Tsk were 0.3±0.1°C and 3.1±0.2°C higher in the HOT compared to the CON trial. Both pre- and within- shift fluid intake were increased two-fold in the heat, and participants in the heat recorded lower USG results than their CON counterparts. There was no difference between the CON and HOT conditions in terms of their work performance, and firefighters in both experimental groups increased their work output over the course of the simulated shift. Though significantly hotter, participants in the heat also managed to avoid excessive cardiovascular and thermal strain, likely aided by the frequent rest breaks in the protocol, and through doubling their fluid intake. Therefore

  10. Exploring occupational and health behavioral causes of firefighter obesity: a qualitative study.

    Science.gov (United States)

    Dobson, Marnie; Choi, BongKyoo; Schnall, Peter L; Wigger, Erin; Garcia-Rivas, Javier; Israel, Leslie; Baker, Dean B

    2013-07-01

    Firefighters, as an occupational group, have one of the highest prevalence rates of obesity. A qualitative study investigated occupational and health behavioral determinants of obesity among firefighters. Four focus groups were conducted with firefighters of every rank as Phase I of the FORWARD study which was designed to assess health behavioral and occupational characteristics related to obesity in firefighters. Analysis revealed five main themes of central importance to firefighters: (1) fire station eating culture; (2) night calls and sleep interruption; (3) supervisor leadership and physical fitness; (4) sedentary work; and (5) age and generational influences. The results showed a strong interrelationship between occupational and health behavioral causes of obesity in firefighters. The relevance of these qualitative findings are discussed along with the implications for future obesity interventions with firefighters. Copyright © 2013 Wiley Periodicals, Inc.

  11. Mesoporous Silicon-Based Anodes for High Capacity, High Performance Li-ion Batteries, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A new high capacity anode composite based on mesoporous silicon is proposed. By virtue of a structure that resembles a pseudo one-dimensional phase, the active anode...

  12. Risk of health complaints and disabilities among Dutch firefighters

    NARCIS (Netherlands)

    Bos, J; Mol, E.; Visser, B.; Frings-Dresen, M.H.W.

    2004-01-01

    Objectives: The purpose of the present study was threefold: (1) to compare the work demands on firefighters (FFs) and office workers (OWs), (2) to compare the prevalence of health complaints and disabilities in the work situation in these two groups, and (3) to explore the effect of work demands on

  13. Firefighter Math - a web-based learning tool

    Science.gov (United States)

    Dan Jimenez

    2010-01-01

    Firefighter Math is a web based interactive resource that was developed to help prepare wildland fire personnel for math based training courses. The website can also be used as a refresher for fire calculations including slope, flame length, relative humidity, flow rates, unit conversion, etc. The website is designed to start with basic math refresher skills and...

  14. Impact of Chronic Diseases on Work Ability in Ageing Firefighters

    NARCIS (Netherlands)

    Plat, Marie-Christine J.; Frings-Dresen, Monique H. W.; Sluiter, Judith K.

    2012-01-01

    Impact of Chronic Diseases on Work Ability in Ageing Firefighters: Marie-Christine J PLAT, et al. Academic Medical Center, University of Amsterdam, Department of Coronel Institute of Occupational Health, The Netherlands-Objectives: The aim of this study was to study the impact of chronic diseases on

  15. Behind the Brotherhood: Rewards and Challenges for Wives of Firefighters

    Science.gov (United States)

    Regehr, Cheryl; Dimitropoulos, Gina; Bright, Elaine; George, Sharon; Henderson, Joscelyn

    2005-01-01

    Support of family is paramount to reducing the impact of highly stressful work on firefighters. Yet the degree of stress encountered by the family members, particularly spouses, resulting from ongoing job demands and exposure to traumatic situations is unclear. This qualitative study examined the effects of emergency service work on spouses of…

  16. Estimation of Forest Fire-fighting Budgets Using Climate Indexes

    NARCIS (Netherlands)

    Xu, Z.; Kooten, van G.C.

    2012-01-01

    Given the complexity and relative short length of current predicting system for fire behavior, it is inappropriate to be referred for planning fire-fighting budgets of BC government due to the severe uncertainty of fire behavior across fire seasons. Therefore, a simple weather derived index for

  17. Evaluation of two cooling systems under a firefighter coverall

    NARCIS (Netherlands)

    Teunissen, L.P.J.; Wang, L.C.; Chou, S.N.; Huang, C.; Jou, G.T.; Daanen, H.A.M.

    2014-01-01

    Firemen often suffer from heat strain. This study investigated two chest cooling systems for use under a firefighting suit. In nine male subjects, a vest with water soaked cooling pads and a vest with water perfused tubes were compared to a control condition. Subjects performed 30 min walking and 10

  18. Pilot task-based assessment of noise levels among firefighters.

    Science.gov (United States)

    Neitzel, Rl; Hong, O; Quinlan, P; Hulea, R

    2013-11-01

    Over one million American firefighters are routinely exposed to various occupational hazards agents. While efforts have been made to identify and reduce some causes of injuries and illnesses among firefighters, relatively little has been done to evaluate and understand occupational noise exposures in this group. The purpose of this pilot study was to apply a task-based noise exposure assessment methodology to firefighting operations to evaluate potential noise exposure sources, and to use collected task-based noise levels to create noise exposure estimates for evaluation of risk of noise-induced hearing loss by comparison to the 8-hr and 24-hr recommended exposure limits (RELs) for noise of 85 and 80.3 dBA, respectively. Task-based noise exposures (n=100 measurements) were measured in three different fire departments (a rural department in Southeast Michigan and suburban and urban departments in Northern California). These levels were then combined with time-at-task information collected from firefighters to estimate 8-hr noise exposures for the rural and suburban fire departments (n=6 estimates for each department). Data from 24-hr dosimetry measurements and crude self-reported activity categories from the urban fire department (n=4 measurements) were used to create 24-hr exposure estimates to evaluate the bias associated with the task-based estimates. Task-based noise levels were found to range from 82-109 dBA, with the highest levels resulting from use of saws and pneumatic chisels. Some short (e.g., 30 min) sequences of common tasks were found to result in nearly an entire allowable daily exposure. The majority of estimated 8-hr and 24-hr exposures exceeded the relevant recommended exposure limit. Predicted 24-hr exposures showed substantial imprecision in some cases, suggesting the need for increased task specificity. The results indicate potential for overexposure to noise from a variety of firefighting tasks and equipment, and suggest a need for further

  19. Psychological stress during exercise: lymphocyte subset redistribution in firefighters.

    Science.gov (United States)

    Huang, Chun-Jung; Webb, Heather E; Garten, Ryan S; Kamimori, Gary H; Acevedo, Edmund O

    2010-10-05

    The purpose of this study examined the changes in heart rate (HR), catecholamines (NE, EPI) and percentages of blood lymphocyte subsets (CD3+ T cells, CD3+CD4+ helper T cells, CD3+CD8+ cytotoxic T cells, CD3- CD56+ NK cells, CD4/CD8 ratio, CD19+ B cells, and total lymphocytes [NK cells+T cells+B cells]) in firefighters exposed to a computerized firefighting strategies and tactics decision-making challenge while participating in moderate intensity exercise. Furthermore, this study also examined the possible relationships between catecholamines (NE and EPI) and blood lymphocyte subsets following combined mental and physical challenge. Ten professional male firefighters participated in two counterbalanced exercise conditions on a cycle ergometer: (1) 37min of cycle ergometry at 60% VO(2max) (exercise alone condition; EAC) and (2) 37min of cycle ergometry at 60% VO(2max) along with 20min of a computerized firefighting strategies and tactics decision-making challenge (firefighting strategies condition; FSC). FSC elicited significantly greater HR, NE, and EPI when compared to EAC. Both EAC and FSC elicited increases in CD3- CD56+ NK cells. The percentages of CD3+ T cells, CD3+CD4+ helper T cells, CD4/CD8 ratio, CD19+ B cells, and total lymphocytes were lower immediately following both conditions. Following dual challenge NE AUC was negatively correlated with percentage of CD19+ B cells immediately post challenge, and HR was negatively associated with the percent change in the CD4/CD8 ratio from pre to post challenge. These elevations in NE and heart rate simultaneously in response to the dual challenge suggest greater sympathetic activation that in turn would possibly explain the alteration in the distribution of lymphocyte subsets. Published by Elsevier Inc.

  20. Firefighter health and fitness assessment: a call to action.

    Science.gov (United States)

    Storer, Thomas W; Dolezal, Brett A; Abrazado, Marlon L; Smith, Denise L; Batalin, Maxim A; Tseng, Chi-Hong; Cooper, Christopher B

    2014-03-01

    Sudden cardiac deaths experienced by firefighters in the line of duty account for the largest proportion of deaths annually. Several fire service standards for fitness and wellness have been recommended but currently only 30% of U.S. fire departments are implementing programs for this purpose. The Department of Homeland Security Science and Technology Directorate has initiated the Physiological Health Assessment System for Emergency Responders (PHASER) program aiming to reduce these line-of-duty deaths through an integration of medical science and sensor technologies. Confirming previous reports, PHASER comprehensive risk assessment has identified lack of physical fitness with propensity for overexertion as a major modifiable risk factor. We sought to determine if current levels of fitness and cardiovascular disease (CVD) risk factors in a contemporary cohort of firefighters were better than those reported over the past 30 years. Fifty-one firefighters from a Southern California department were characterized for physical fitness and CVD risk factors using standard measures. Overall, physical fitness and risk factors were not different from previous reports of firefighter fitness and most subjects did not achieve recommended fitness standards. Considering the lack of widespread implementation of wellness/fitness programs in the U.S. fire service together with our findings that low physical fitness and the presence of CVD risk factors persist, we issue a call to action among health and fitness professionals to assist the fire service in implementing programs for firefighters that improve fitness and reduce CVD risk factors. Fitness professionals should be empowered to work with fire departments lending their expertise to guide programs that achieve these objectives, which may then lead to reduced incidence of sudden cardiac death or stroke.

  1. Firefighter burn injuries: predictable patterns influenced by turnout gear.

    Science.gov (United States)

    Kahn, Steven A; Patel, Jignesh H; Lentz, Christopher W; Bell, Derek E

    2012-01-01

    Approximately 100 firefighters suffer fatal injuries annually and tens of thousands receive nonfatal injuries. Many of these injuries require medical attention and restricted activity but may be preventable. This study was designed to elucidate etiology, circumstances, and patterns of firefighter burn injury so that further prevention strategies can be designed. In particular, modification of protective equipment, or turnout gear, is one potential strategy to prevent burn injury. An Institutional Review Board-approved retrospective review was conducted with records of firefighters treated for burn injury from 2005 to 2009. Data collected included age, gender, TBSA, burn depth, anatomic location, total hospital days per patient, etiology, and circumstances of injury. Circumstances of injury were stratified into the following categories: removal/dislodging of equipment, failure of equipment to protect, training errors, and when excessive external temperatures caused patient sweat to boil under the gear. Over the 4-year period, 20 firefighters were treated for burn injury. Mean age was 38.9 ± 8.9 years and 19 of 20 patients were male. Mean burn size was 1.1 ± 2.7% TBSA. Eighteen patients suffered second-degree burns, while two patients suffered first-degree burns. Mean length of hospitalization was 2.45 days. Scald burns were responsible for injury to 13 firefighters (65%). Flame burns caused injury to four patients (20%). Only three patients received contact burns (15%). The face was the site most commonly burned, representing 29% of injuries. The hand/wrist and ears were the next largest groups, with 23 and 16% of the injuries, respectively. Other areas burned included the neck (10%), arm (6.5%), leg (6.5%), knees (3%), shoulders (3%), and head (3%). Finally, the circumstance of injury was evaluated for each patient. Misuse and noncontiguous areas of protective equipment accounted for 14 of the 20 injuries (70%). These burns were caused when hot steam

  2. Impact of Different Personal Protective Clothing on Wildland Firefighters' Physiological Strain

    OpenAIRE

    Carballo-Leyenda, Belén; Villa, José G.; López-Satué, Jorge; Rodríguez-Marroyo, Jose A.

    2017-01-01

    Wildfire firefighting is an extremely demanding occupation performed under hot environment. The use of personal protective clothing (PPC) is needed to protect subjects from the thermal exposure. However, the additional use of PPC may increase the wildland firefighters' physiological strain, and consequently limit their performance. The aim of this study was to analyze the effect of four different PPC on the physiological strain of wildland firefighters under moderate conditions (30?C and 30% ...

  3. Exploring occupational and behavioral risk factors for obesity in firefighters: A theoretical framework and study design

    OpenAIRE

    Choi, BK; Schnall, P; Dobson, M; Israel, L; Landsbergis, P; Galassetti, P; Pontello, A; Kojaku, S; Baker, D

    2011-01-01

    Firefighters and police officers have the third highest prevalence of obesity among 41 male occupational groups in the United States (US). However, few studies have examined the relationship of firefighter working conditions and health behaviors with obesity. This paper presents a theoretical framework describing the relationship between working conditions, health behaviors, and obesity in firefighters. In addition, the paper describes a detailed study plan for exploring the role of occupatio...

  4. EFFICIENCY OF FIRE-FIGHTING PROTECTION OBJECTS IN PROVISION OF FIRE SAFETY AT INDUSTRIAL ENTERPRISES

    OpenAIRE

    A. V. Zhovna

    2008-01-01

    The paper gives an analysis of economic results pertaining to organization of a system for fire-fighting protection of industrial enterprises in theRepublicofBelarus. Statistical data on operational conditions of technical means of fire-fighting protection, particularly, automatic systems for detection and extinguishing of fires, systems of internal fire-fighting water-supply.  Requirements and provisions  of normative and technical documents are thoroughly studied. Observance of these docume...

  5. Mechanics of high-capacity electrodes in lithium-ion batteries

    International Nuclear Information System (INIS)

    Zhu, Ting

    2016-01-01

    Rechargeable batteries, such as lithium-ion batteries, play an important role in the emerging sustainable energy landscape. Mechanical degradation and resulting capacity fade in high-capacity electrode materials critically hinder their use in high-performance lithium-ion batteries. This paper presents an overview of recent advances in understanding the electrochemically-induced mechanical behavior of the electrode materials in lithium-ion batteries. Particular emphasis is placed on stress generation and facture in high-capacity anode materials such as silicon. Finally, we identify several important unresolved issues for future research. (topical review)

  6. ACUTE CARDIOVASCULAR EFFECTS OF FIREFIGHTING AND ACTIVE COOLING DURING REHABILITATION

    Science.gov (United States)

    Burgess, Jefferey L.; Duncan, Michael D.; Hu, Chengcheng; Littau, Sally R.; Caseman, Delayne; Kurzius-Spencer, Margaret; Davis-Gorman, Grace; McDonagh, Paul F.

    2012-01-01

    Objectives To determine the cardiovascular and hemostatic effects of fire suppression and post-exposure active cooling. Methods Forty-four firefighters were evaluated prior to and after a 12 minute live-fire drill. Next, 50 firefighters undergoing the same drill were randomized to post-fire forearm immersion in 10°C water or standard rehabilitation. Results In the first study, heart rate and core body temperature increased and serum C-reactive protein decreased but there were no significant changes in fibrinogen, sE-selectin or sL-selectin. The second study demonstrated an increase in blood coagulability, leukocyte count, factors VIII and X, cortisol and glucose, and a decrease in plasminogen and sP-selectin. Active cooling reduced mean core temperature, heart rate and leukocyte count. Conclusions Live-fire exposure increased core temperature, heart rate, coagulability and leukocyte count; all except coagulability were reduced by active cooling. PMID:23090161

  7. 75 FR 54026 - Salvage and Marine Firefighting Requirements; Vessel Response Plans for Oil

    Science.gov (United States)

    2010-09-03

    ... information for resource providers for each vessel with appropriate equipment and resources located in each... appropriate salvage and marine firefighting resources were identified and available for responding to...

  8. [Severe Eyeball and Facial Skeletal Injuries Caused by Firefighting Sport].

    Science.gov (United States)

    Rusňák, Š; Maranová, Z; Kasl, Z; Hecová, L; Voigt, E; Raiskup, F

    2017-07-01

    The aim of this work is to draw attention to possible injuries of the eye and the facial skeleton caused by firefighting sport. There was a group of 9 patients presented who were treated from 2006 to 2015 in the Department of Ophthalmology at the University Hospital in Pilsen and diagnosed with severe eyeball contusion after being hit by a jet of water and/or a water pipe. Three cases are presented in detail. Georg Thieme Verlag KG Stuttgart · New York.

  9. Firefighter injuries are not just a fireground problem.

    Science.gov (United States)

    Frost, D M; Beach, T A C; Crosby, I; McGill, S M

    2015-01-01

    Linking firefighter injury reporting to general motion patterns may provide insight into potential injury mechanisms and the development of prevention strategies. To characterize the injuries sustained by members of a large Canadian metropolitan fire department over a 5-year span. Data were taken from injury reports filed by career firefighters between 2007 and 2011. Injuries were described by job duty, type, body part affected, and the general motion pattern employed at the time of injury (e.g. lifting). Of the 1311 injuries reported, 64% were categorized as sprains and strains (musculoskeletal disorders -MSDs), the most frequent of which affected the back (32%). Categorized by job duty, 65% of MSDs were sustained while working at the fire station or during physical training-related activities. Only 15% were attributed to fireground operations. Furthermore, the associated job duty could not differentiate the types of injuries sustained; back injuries occurred primarily while lifting, knee injuries while stepping, and shoulder injuries during pushing/pulling-related activities. Firefighter injuries are not just a fireground problem. Injury causation may be better understood by linking the injury location and type with motion patterns rather than job duties. This information could assist in developing general prevention strategies for the fire service.

  10. Beyond the magic number four: Remapping high-capacity, pre-attentive, fragile working memory

    NARCIS (Netherlands)

    Zerr, P.; Gayet, S.; Mulder, K.T.; Sligte, I.G.; Stigchel, S. van der

    2017-01-01

    Visual short term memory allows us to access visual information after termination of its retinal input. Generally, a distinction is made between a robust, capacity-limited form (working memory, WM) and high-capacity, pre-attentive, maskable forms (sensory memory, e.g. fragile memory, FM). Eye

  11. Impact of Work Task-Related Acute Occupational Smoke Exposures on Select Proinflammatory Immune Parameters in Wildland Firefighters

    Science.gov (United States)

    Objective: A repeated measures study was used to assess the effect of work tasks on select proinflammatory biomarkers in firefighters working at prescribed burns. Methods: Ten firefighters and two volunteers were monitored for particulate matter and carbon monoxide on workdays, ...

  12. Relationship between burnout and PTSD symptoms in firefighters: the moderating effects of a sense of calling to firefighting.

    Science.gov (United States)

    Jo, Insung; Lee, Songhee; Sung, Gyhye; Kim, Minkyoung; Lee, Sanghyuk; Park, Jooeon; Lee, Kangsoo

    2018-01-01

    Firefighting has been reported to lead to burnout and posttraumatic stress disorder (PTSD). However, burnout and PTSD symptoms may vary depending on personal characteristics, such as having a sense of calling. This study examined the role of calling in the association between burnout and PTSD symptoms. We hypothesized that burnout would be associated with more severe PTSD symptoms and calling would buffer the relationship between burnout and PTSD symptoms. The Korean version of the Maslach Burnout Inventory-General Survey, Sense of Calling Subscale of the Professionalism Scale, and the Impact of Event Scale-Revised-Korean version were used to measure burnout, calling, and PTSD symptoms. Data from 109 of 127 firefighters from Gyeonggi-do, South Korea were analyzed using hierarchical linear regression. Burnout was a significant predictor of PTSD symptoms. Furthermore, the interaction term between burnout and calling accounted for a significant variance in PTSD symptoms. Higher burnout was associated with severe PTSD symptoms, but this relationship differed by the level of calling. The increase in PTSD symptoms due to increased burnout in the high calling group was relatively higher than in the low and average calling groups. Calling, though perceived as a positive variable, can be hazardous to exhausted people. A sense of calling as part of one's job identity should not be encouraged until personal circumstances and characteristics, such burnout symptoms, are evaluated. Identifying context and variables associated with PTSD for interventions with firefighters and persons in other dangerous occupations should aid in their recovery from trauma exposure.

  13. 33 CFR 155.4035 - Required pre-incident information and arrangements for the salvage and marine firefighting...

    Science.gov (United States)

    2010-07-01

    ... and arrangements for the salvage and marine firefighting resource providers listed in response plans... marine firefighting resource providers listed in response plans. (a) You must provide the information listed in §§ 155.1035(c) and 155.1040(c) to your salvage and marine firefighting resource providers. (b...

  14. Evaluation of Ultra High Pressure (UHP) Firefighting in a Room-and-Contents Fire

    Science.gov (United States)

    2017-03-15

    legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or...venomous insects. Abort Criteria and Procedures If a fire has already been lit and an abort is necessary, the firefighter(s) will attempt to put

  15. Firefighters United for Safety, Ethics, and Ecology (FUSEE): Torchbearers for a new fire management paradigm

    Science.gov (United States)

    Timothy Ingalsbee; Joseph Fox; Patrick Withen

    2007-01-01

    Firefighters United for Safety, Ethics, and Ecology (FUSEE) is a nonprofit organization promoting safe, ethical, ecological wildland fire management. FUSEE believes firefighter and community safety are ultimately interdependent with ethical public service, wildlands protection, and ecological restoration of fire-adapted ecosystems. Our members include current, former,...

  16. The Relationship between Physical Activity and Thermal Protective Clothing on Functional Balance in Firefighters

    Science.gov (United States)

    Kong, Pui W.; Suyama, Joe; Cham, Rakie; Hostler, David

    2012-01-01

    We investigated the relationship between baseline physical training and the use of firefighting thermal protective clothing (TPC) with breathing apparatus on functional balance. Twenty-three male firefighters performed a functional balance test under four gear/clothing conditions. Participants were divided into groups by physical training status,…

  17. Cardiorespiratory Fitness Is Associated with Gait Changes among Firefighters after a Live Burn Training Evolution

    Directory of Open Access Journals (Sweden)

    Deanna Colburn

    2017-06-01

    Conclusion: A 14-MET criterion failed to distinguish gait or balance characteristics in this group. However, less fit firefighters did require more time to complete the balance test (p = 0.003. Aerobic fitness alone does not predict gait changes among firefighters following a live burn evolution but does appear to influence functional balance.

  18. 14 CFR 139.315 - Aircraft rescue and firefighting: Index determination.

    Science.gov (United States)

    2010-01-01

    ... 14 Aeronautics and Space 3 2010-01-01 2010-01-01 false Aircraft rescue and firefighting: Index... CERTIFICATION OF AIRPORTS Operations § 139.315 Aircraft rescue and firefighting: Index determination. (a) An index is required by paragraph (c) of this section for each certificate holder. The Index is determined...

  19. Physiological responses to simulated stair climbing in professional firefighters wearing rubber and leather boots.

    Science.gov (United States)

    Huang, Chun-Jung; Garten, Ryan S; Wade, Chip; Webb, Heather E; Acevedo, Edmund O

    2009-09-01

    No studies have considered whether a firefighter's boots are a factor influencing physiological responses. The purpose of this study was to examine physiological responses to a fire simulation activity (stair climb) in professional firefighters wearing rubber boots (RB) and leather boots (LB). Twelve professional firefighters participated in two counterbalanced simulated firefighter stair climb (SFSC) sessions, one wearing RB and the other wearing LB. Heart rate, oxygen uptake (VO(2)), expiratory ventilation (V(E)), blood lactate (BLa), salivary cortisol (SCORT), and leg strength were assessed prior to and following a SFSC. LB elicited significantly greater SCORT values and knee flexion time to peak torque. Furthermore, RB revealed significantly greater ankle dorsiflexion peak torque after SFSC. BLa was positively related to knee flexion peak torque after SFSC in the RB. Firefighters when wearing the RB may be more effective at resisting fatigue and increase more force production.

  20. Estimation of Parameters Obtained by Electrochemical Impedance Spectroscopy on Systems Containing High Capacities

    Directory of Open Access Journals (Sweden)

    Mirjana Rajčić Vujasinović

    2009-09-01

    Full Text Available Electrochemical systems with high capacities demand devices for electrochemical impedance spectroscopy (EIS with ultra-low frequencies (in order of mHz, that are almost impossible to accomplish with analogue techniques, but this becomes possible by using a computer technique and accompanying digital equipment. Recently, an original software and hardware for electrochemical measurements, intended for electrochemical systems exhibiting high capacities, such as supercapacitors, has been developed. One of the included methods is EIS. In this paper, the method of calculation of circuit parameters from an EIS curve is described. The results of testing on a physical model of an electrochemical system, constructed of known elements (including a 1.6 F capacitor in a defined arrangement, proved the validity of the system and the method.

  1. Radiation and temperature effects on electronic components investigated under the CSTI high capacity power project

    International Nuclear Information System (INIS)

    Schwarze, G.E.; Niedra, J.M.; Frasca, A.J.; Wieserman, W.R.

    1993-01-01

    The effects of nuclear radiation and high temperature environments must be fully known and understood for the electronic components and materials used in both the Power Conditioning and Control subsystem and the reactor Instrumentation and Control subsystem of future high capacity nuclear space power systems. This knowledge is required by the designer of these subsystems in order to develop highly reliable, long-life power systems for future NASA missions. A review and summary of the experimental results obtained for the electronic components and materials investigated under the power management element of the CSTI high capacity power project will be presented in this paper: (1) Neutron, gamma ray, and temperature effects on power semiconductor switches, (2) Temperature and frequency effects on soft magnetic materials; and (3) Temperature effects on rare-earth permanent magnets

  2. High-Capacity Hydrogen-Based Green-Energy Storage Solutions For The Grid Balancing

    Science.gov (United States)

    D'Errico, F.; Screnci, A.

    One of the current main challenges in green-power storage and smart grids is the lack of effective solutions for accommodating the unbalance between renewable energy sources, that offer intermittent electricity supply, and a variable electricity demand. Energy management systems have to be foreseen for the near future, while they still represent a major challenge. Integrating intermittent renewable energy sources, by safe and cost-effective energy storage systems based on solid state hydrogen is today achievable thanks to recently some technology breakthroughs. Optimized solid storage method made of magnesium-based hydrides guarantees a very rapid absorption and desorption kinetics. Coupled with electrolyzer technology, high-capacity storage of green-hydrogen is therefore practicable. Besides these aspects, magnesium has been emerging as environmentally friend energy storage method to sustain integration, monitoring and control of large quantity of GWh from high capacity renewable generation in the EU.

  3. Radiation and temperature effects on electronic components investigated under the CSTI High Capacity Power Project

    International Nuclear Information System (INIS)

    Shwarze, G.E.; Wieserman, W.R.

    1994-01-01

    The effects of nuclear radiation and high temperature environments must be fully known and understood for the electronic components and materials used in both the Power Conditioning and Control subsystem and the reactor Instrumentation and Control subsystem of future high capacity nuclear space power systems. This knowledge is required by the designer of these subsystems in order to develop highly reliable, long-life power systems for future NASA missions. A review and summary of the experimental results obtained for the electronic components and materials investigated under the power management element of the CSTI high capacity power project will be presented in this paper: (1) Neutron, gamma ray, and temperature effects on power semiconductor switches, (2) Temperature and frequency effects on soft magnetic materials; and (3) Temperature effects on rare earth permanent magnets

  4. Silicon oxide based high capacity anode materials for lithium ion batteries

    Science.gov (United States)

    Deng, Haixia; Han, Yongbong; Masarapu, Charan; Anguchamy, Yogesh Kumar; Lopez, Herman A.; Kumar, Sujeet

    2017-03-21

    Silicon oxide based materials, including composites with various electrical conductive compositions, are formulated into desirable anodes. The anodes can be effectively combined into lithium ion batteries with high capacity cathode materials. In some formulations, supplemental lithium can be used to stabilize cycling as well as to reduce effects of first cycle irreversible capacity loss. Batteries are described with surprisingly good cycling properties with good specific capacities with respect to both cathode active weights and anode active weights.

  5. Very Long (> 48 hours) Shifts and Cardiovascular Strain in Firefighters: a Theoretical Framework.

    Science.gov (United States)

    Choi, Bongkyoo; Schnall, Peter L; Dobson, Marnie; Garcia-Rivas, Javier; Kim, Hyoungryoul; Zaldivar, Frank; Israel, Leslie; Baker, Dean

    2014-03-06

    Shift work and overtime have been implicated as important work-related risk factors for cardiovascular disease (CVD). Many firefighters who contractually work on a 24-hr work schedule, often do overtime (additional 24-hr shifts) which can result in working multiple, consecutive 24-hr shifts. Very little research has been conducted on firefighters at work that examines the impact of performing consecutive 24-hr shifts on cardiovascular physiology. Also, there have been no standard field methods for assessing in firefighters the cardiovascular changes that result from 24-hr shifts, what we call "cardiovascular strain". The objective of this study, as the first step toward elucidating the role of very long (> 48 hrs) shifts in the development of CVD in firefighters, is to develop and describe a theoretical framework for studying cardiovascular strain in firefighters on very long shifts (i.e., > 2 consecutive 24-hr shifts). The developed theoretical framework was built on an extensive literature review, our recently completed studies with firefighters in Southern California, e-mail and discussions with several firefighters on their experiences of consecutive shifts, and our recently conducted feasibility study in a small group of firefighters of several ambulatory cardiovascular strain biomarkers (heart rate, heart rate variability, blood pressure, salivary cortisol, and salivary C-reactive protein). The theoretical framework developed in this study will facilitate future field studies on consecutive 24-hr shifts and cardiovascular health in firefighters. Also it will increase our understanding of the mechanisms by which shift work or long work hours can affect CVD, particularly through CVD biological risk factors, and thereby inform policy about sustainable work and rest schedules for firefighters.

  6. Reversible anionic redox chemistry in high-capacity layered-oxide electrodes

    Science.gov (United States)

    Sathiya, M.; Rousse, G.; Ramesha, K.; Laisa, C. P.; Vezin, H.; Sougrati, M. T.; Doublet, M.-L.; Foix, D.; Gonbeau, D.; Walker, W.; Prakash, A. S.; Ben Hassine, M.; Dupont, L.; Tarascon, J.-M.

    2013-09-01

    Li-ion batteries have contributed to the commercial success of portable electronics and may soon dominate the electric transportation market provided that major scientific advances including new materials and concepts are developed. Classical positive electrodes for Li-ion technology operate mainly through an insertion-deinsertion redox process involving cationic species. However, this mechanism is insufficient to account for the high capacities exhibited by the new generation of Li-rich (Li1+xNiyCozMn(1-x-y-z)O2) layered oxides that present unusual Li reactivity. In an attempt to overcome both the inherent composition and the structural complexity of this class of oxides, we have designed structurally related Li2Ru1-ySnyO3 materials that have a single redox cation and exhibit sustainable reversible capacities as high as 230 mA h g-1. Moreover, they present good cycling behaviour with no signs of voltage decay and a small irreversible capacity. We also unambiguously show, on the basis of an arsenal of characterization techniques, that the reactivity of these high-capacity materials towards Li entails cumulative cationic (Mn+→M(n+1)+) and anionic (O2-→O22-) reversible redox processes, owing to the d-sp hybridization associated with a reductive coupling mechanism. Because Li2MO3 is a large family of compounds, this study opens the door to the exploration of a vast number of high-capacity materials.

  7. High-Capacity Cathode Material with High Voltage for Li-Ion Batteries.

    Science.gov (United States)

    Shi, Ji-Lei; Xiao, Dong-Dong; Ge, Mingyuan; Yu, Xiqian; Chu, Yong; Huang, Xiaojing; Zhang, Xu-Dong; Yin, Ya-Xia; Yang, Xiao-Qing; Guo, Yu-Guo; Gu, Lin; Wan, Li-Jun

    2018-03-01

    Electrochemical energy storage devices with a high energy density are an important technology in modern society, especially for electric vehicles. The most effective approach to improve the energy density of batteries is to search for high-capacity electrode materials. According to the concept of energy quality, a high-voltage battery delivers a highly useful energy, thus providing a new insight to improve energy density. Based on this concept, a novel and successful strategy to increase the energy density and energy quality by increasing the discharge voltage of cathode materials and preserving high capacity is proposed. The proposal is realized in high-capacity Li-rich cathode materials. The average discharge voltage is increased from 3.5 to 3.8 V by increasing the nickel content and applying a simple after-treatment, and the specific energy is improved from 912 to 1033 Wh kg -1 . The current work provides an insightful universal principle for developing, designing, and screening electrode materials for high energy density and energy quality. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Physical and psychological determinants of injury in Ontario forest firefighters.

    Science.gov (United States)

    Gordon, H; Larivière, M

    2014-12-01

    Forest firefighters are faced with multiple physical and psychological challenges as a result of their duties. Little is known about the determinants of injury among these workers. The Ontario Ministry of Natural Resources (OMNR) Aviation, Forest Fire and Emergency Services (AFFES) records detailed information on two mutually exclusive types of workplace injury: First aid (self-reported) and Workplace Safety Insurance Board (WSIB, i.e. received medical attention). To identify the contributions of physical and psychological factors on the likelihood of injury among forest firefighters. Participants were male and female forest firefighters aged between 18 and 65. Data were collected using two self-administered instruments: The NEO Personality Inventory and the Job Stress Survey. Secondary data were collected from the OMNR AFFES and data were analysed by way of multivariate statistical procedures. There were 252 participants. Those who were older, had a history of injury, had high scores for the personality construct of Neuroticism or low scores for the Openness construct were significantly more likely to incur a first aid injury, while those with high experience levels were significantly less likely to incur injury (P First aid and WSIB injuries in the OMNR AFFES were quite distinct phenomena and different factors need consideration in their prediction. It is recommended that managers and decision-makers in this field consider factors such as job stress, personality and the prior occurrence of injuries in their assessment of risk. © The Author 2014. Published by Oxford University Press on behalf of the Society of Occupational Medicine. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  9. Prediction of dry ice mass for firefighting robot actuation

    Science.gov (United States)

    Ajala, M. T.; Khan, Md R.; Shafie, A. A.; Salami, MJE; Mohamad Nor, M. I.

    2017-11-01

    The limitation in the performance of electric actuated firefighting robots in high-temperature fire environment has led to research on the alternative propulsion system for the mobility of firefighting robots in such environment. Capitalizing on the limitations of these electric actuators we suggested a gas-actuated propulsion system in our earlier study. The propulsion system is made up of a pneumatic motor as the actuator (for the robot) and carbon dioxide gas (self-generated from dry ice) as the power source. To satisfy the consumption requirement (9cfm) of the motor for efficient actuation of the robot in the fire environment, the volume of carbon dioxide gas, as well as the corresponding mass of the dry ice that will produce the required volume for powering and actuation of the robot, must be determined. This article, therefore, presents the computational analysis to predict the volumetric requirement and the dry ice mass sufficient to power a carbon dioxide gas propelled autonomous firefighting robot in a high-temperature environment. The governing equation of the sublimation of dry ice to carbon dioxide is established. An operating time of 2105.53s and operating pressure ranges from 137.9kPa to 482.65kPa were achieved following the consumption rate of the motor. Thus, 8.85m3 is computed as the volume requirement of the CAFFR while the corresponding dry ice mass for the CAFFR actuation ranges from 21.67kg to 75.83kg depending on the operating pressure.

  10. The Influence of Exposure to Natural Disasters on Depression and PTSD Symptoms among Firefighters.

    Science.gov (United States)

    Pennington, Michelle L; Carpenter, Thomas P; Synett, Samantha J; Torres, Victoria A; Teague, Jennifer; Morissette, Sandra B; Knight, Jeffrey; Kamholz, Barbara W; Keane, Terence M; Zimering, Rose T; Gulliver, Suzy B

    2018-02-01

    Introduction Firefighters represent an important population for understanding the consequences of exposure to potentially traumatic stressors. Hypothesis/Problem The researchers were interested in the effects of pre-employment disaster exposure on firefighter recruits' depression and posttraumatic stress disorder (PTSD) symptoms during the first three years of fire service and hypothesized that: (1) disaster-exposed firefighters would have greater depression and PTSD symptoms than non-exposed overall; and (2) depression and PTSD symptoms would worsen over years in fire service in exposed firefighters, but not in their unexposed counterparts. In a baseline interview, 35 male firefighter recruits from seven US cities reported lifetime exposure to natural disaster. These disaster-exposed male firefighter recruits were matched on age, city, and education with non-exposed recruits. A generalized linear mixed model revealed a significant exposure×time interaction (e coef =1.04; Pdisaster exposure only. This pattern persisted after controlling for social support from colleagues (e coefficient=1.05; Pdisaster exposure only, even after controlling for social support. Posttraumatic stress disorder symptoms did not vary between exposure groups. Pennington ML , Carpenter TP , Synett SJ , Torres VA , Teague J , Morissette SB , Knight J , Kamholz BW , Keane TM , Zimering RT , Gulliver SB . The influence of exposure to natural disasters on depression and PTSD symptoms among firefighters. Prehosp Disaster Med. 2018;33(1):102-108.

  11. Most cancer in firefighters is due to radio-frequency radiation exposure not inhaled carcinogens.

    Science.gov (United States)

    Milham, S

    2009-11-01

    Recent reviews and reports of cancer incidence and mortality in firefighters conclude that they are at an increased risk of a number of cancers. These include leukemia, multiple myeloma, non-Hodgkin's lymphoma, male breast cancer, malignant melanoma, and cancers of the brain, stomach, colon, rectum, prostate, urinary bladder, testes, and thyroid. Firefighters are exposed to a long list of recognized or probable carcinogens in combustion products and the presumed route of exposure to these carcinogens is by inhalation. Curiously, respiratory system cancers and diseases are usually not increased in firefighters as they are in workers exposed to known inhaled carcinogens. The list of cancers with increased risk in firefighters strongly overlaps the list of cancers at increased risk in workers exposed to electromagnetic fields (EMF) and radiofrequency radiation (RFR). Firefighters have increased exposure to RFR in the course of their work, from the mobile two-way radio communications devices which they routinely use while fighting fires, and at times from firehouse and fire vehicle radio transmitters. I suggest that some of the increased cancer risk in firefighters is caused by RFR exposure, and is therefore preventable. The precautionary principle should be applied to reduce the risk of cancer in firefighters, and workman's compensation rules will necessarily need to be modified.

  12. Prevalence rate of post-traumatic stress disorders (PTSD and other psychological disorders among Saudi firefighters

    Directory of Open Access Journals (Sweden)

    Mohammed Alghamd

    2013-08-01

    Full Text Available Background: Firefighters have a high probability of being exposed to a variety of traumatic events. Potentially traumatic events can occur during a single rescue such as: providing aid to seriously injured or helpless victims. Moreover, firefighters who are injured in the line of duty may have to retire as a consequence of their injury. The psychological cost of this exposure may increase the risk of long-term problems, such as post-traumatic stress disorder (PTSD symptoms, depression, and anxiety. Objective: The purpose of this study was to investigate the prevalence of PTSD symptoms, depression, anxiety, and assess related variables such as coping strategies and social support among Saudi firefighters. Method: Two hundred firefighters completed the Fire-fighter Trauma History Screen (FTHS to measure the number of traumatic events, Screen for Post-traumatic Stress Symptoms (SPTSS scale to assess the prevalence of PTSD symptoms, Hospital Anxiety and Depression Scales (HADS to assess depression and anxiety, Brief Cope (BC scale to measure coping strategies used, and Social Support scale was used to evaluate the firefighter's support received. Results: The results showed that 84% (169/200 of firefighters were exposed to at least one traumatic event. The result presented that 57% (96/169 of exposure firefighters fully met the DSM-IV criteria for PTSD with high levels of depression and anxiety; 39% (66/169 partially met the PTSD criteria. However, only 4% participants have not met the PTSD criteria. The results also revealed that adaptive coping strategies and higher perceived social support was associated with lower levels of PTSD. Conclusion: The high prevalence rate of PTSD related to the type and severity of the traumatic events and years of experience in the job. Accordingly, many firefighters were severely affected by their experiences, and we should be developing methods to help them.

  13. Obesity and Injury-Related Absenteeism in a Population-Based Firefighter Cohort

    Science.gov (United States)

    Poston, Walker S.C.; Jitnarin, Nattinee; Haddock, C. Keith; Jahnke, Sara A.; Tuley, Brianne C.

    2018-01-01

    A consistent relationship has been demonstrated between obesity and absenteeism in the workplace. However, most studies have focused on primarily sedentary occupational groups. Firefighting is a physically demanding profession that involves significant potential for exposure to dangerous situations and strenuous work. No studies to date have evaluated the impact of obesity on risk for absenteeism among firefighters. We examined the cross-sectional association between BMI and obesity and injury-related absenteeism. BMI, body fat percentage (BF%), waist circumference (WC), injury, and injury-related absenteeism were assessed in 478 career male firefighters. One hundred and fifteen firefighters reported an injury in the previous year and the number of days absent from work due to their injury. BMI was an independent predictor of absenteeism due to injury even after adjustment for confounding variables. Firefighters meeting the definition of class II and III obesity had nearly five times (odds ratio (OR) = 4.89; 95% confidence interval (CI) = 3.63–6.58) the number missed work days due to injury when compared to their normal weight counterparts and their elevated risk was greater than firefighters with class I obesity (OR = 2.71; 95% CI = 2.01–3.65) or those who were overweight (OR = 2.55; 95% CI = 1.90–3.41). The attributable per capita costs of class II and III obesity-related absenteeism over the last year were $1,682.90 per firefighter, $254.00 per firefighter for class I obesity, and $74.41 per firefighter for overweight. Our findings suggest that class II and III obesity were associated with substantial attributable costs to employers and our cost estimates probably underestimate the actual financial burden. PMID:21633400

  14. Serum heavy metals and hemoglobin related compounds in Saudi Arabia firefighters

    Directory of Open Access Journals (Sweden)

    Al-Malki Abdulrahman L

    2009-07-01

    Full Text Available Abstract Background Firefighters are frequently exposed to significant concentrations of hazardous materials including heavy metals, aldehydes, hydrogen chloride, dichlorofluoromethane and some particulates. Many of these materials have been implicated in the triggering of several diseases. The aim of the present study is to investigate the effect of fire smoke exposure on serum heavy metals and possible affection on iron functions compounds (total iron binding capacity, transferrin saturation percent, ferritin, unsaturated iron-binding capacity blood hemoglobin and carboxyhemoglobin,. Subjects and methods Two groups of male firefighter volunteers were included; the first included 28 firefighters from Jeddah city, while the second included 21 firefighters from Yanbu city with an overall age rang of 20–48 years. An additional group of 23 male non-firefighters volunteered from both cities as normal control subjects. Blood samples were collected from all volunteer subjects and investigated for relevant parameters. Results The results obtained showed that there were no statistically significant changes in the levels of serum heavy metals in firefighters as compared to normal control subjects. Blood carboxyhemoglobin and serum ferritin were statistically increased in Jeddah firefighters, (p Conclusion Such results might point to the need for more health protective and prophylactic measures to avoid such hazardous health effects (elevated Blood carboxyhemoglobin and serum ferritin and decreased serum TIBC and UIBC that might endanger firefighters working under dangerous conditions. Firefighters must be under regular medical follow-up through standard timetabled medical laboratory investigations to allow for early detection of any serum biochemical or blood hematological changes.

  15. Titanium-decorated graphene for high-capacity hydrogen storage studied by density functional simulations

    International Nuclear Information System (INIS)

    Liu Yali; Ren Ling; He Yao; Cheng Haiping

    2010-01-01

    We present results of density functional theory (DFT) calculations of the adsorption of hydrogen molecules on Ti-decorated graphene. Our results indicate that the binding energies of molecular hydrogen on Ti-decorated graphene can be dramatically enhanced to 0.23-0.60 eV. The hybridization of the Ti 3d orbitals with the H 2 σ and σ* orbitals plays a central role in the enhanced binding. There is also a contribution from the attractive interaction between the surface dipole and the dipole of polarized H 2 . It can be expected that Ti-decorated graphene could be considered as a potential high-capacity hydrogen storage medium.

  16. The Sensory Components of High-Capacity Iconic Memory and Visual Working Memory

    OpenAIRE

    Bradley, Claire; Pearson, Joel

    2012-01-01

    Early visual memory can be split into two primary components: a high-capacity, short-lived iconic memory followed by a limited-capacity visual working memory that can last many seconds. Whereas a large number of studies have investigated visual working memory for low-level sensory features, much research on iconic memory has used more “high-level” alphanumeric stimuli such as letters or numbers. These two forms of memory are typically examined separately, despite an intrinsic overlap in their...

  17. OTDM Networking for Short Range High-Capacity Highly Dynamic Networks

    DEFF Research Database (Denmark)

    Medhin, Ashenafi Kiros

    This PhD thesis aims at investigating the possibility of designing energy-efficient high-capacity (up to Tbit/s) optical network scenarios, leveraging on the effect of collective switching of many bits simultaneously, as is inherent in high bit rate serial optical data signals. The focus...... is on short range highly dynamic networks, catering to data center needs. The investigation concerns optical network scenarios, and experimental implementations of high bit rate serial data packet generation and reception, scalable optical packet labeling, simple optical label extraction and stable ultra...

  18. Development and Testing of a High Capacity Plasma Chemical Reactor in the Ukraine

    Energy Technology Data Exchange (ETDEWEB)

    Reilly, Raymond W.

    2012-07-30

    This project, Development and Testing of a High Capacity Plasma Chemical Reactor in the Ukraine was established at the Kharkiv Institute of Physics and Technology (KIPT). The associated CRADA was established with Campbell Applied Physics (CAP) located in El Dorado Hills, California. This project extends an earlier project involving both CAP and KIPT conducted under a separate CRADA. The initial project developed the basic Plasma Chemical Reactor (PCR) for generation of ozone gas. This project built upon the technology developed in the first project, greatly enhancing the output of the PCR while also improving reliability and system control.

  19. The sensory components of high-capacity iconic memory and visual working memory

    OpenAIRE

    Claire eBradley; Claire eBradley; Joel ePearson

    2012-01-01

    Early visual memory can be split into two primary components: a high-capacity, short-lived iconic memory followed by a limited-capacity visual working memory that can last many seconds. Whereas a large number of studies have investigated visual working memory for low-level sensory features, much research on iconic memory has used more high-level alphanumeric stimuli such as letters or numbers. These two forms of memory are typically examined separately, despite an intrinsic overlap in their c...

  20. The Big Five Personality Traits and French Firefighter Burnout: The Mediating Role of Achievement Goals.

    Science.gov (United States)

    Vaulerin, Jérôme; Colson, Serge S; Emile, Mélanie; Scoffier-Mériaux, Stéphanie; d'Arripe-Longueville, Fabienne

    2016-04-01

    We investigated the associations between the Big Five personality traits and occupational burnout in firefighters and the mediating role of achievement goals in this relationship. Two hundred twenty male firefighters from 20 to 62 years old participated and mediation analyses were performed. The results showed that neuroticism was positively related to the three dimensions of burnout, both directly and through mastery avoidance goals. Mastery approach goals mediated the relationships between conscientiousness and physical fatigue and between openness to experience and physical fatigue. Three of the Big Five personality traits, neuroticism, conscientiousness and openness to experience, and achievement goals, may be important factors in understanding and preventing firefighter burnout.

  1. Charge Modulation in Graphitic Carbon Nitride as a Switchable Approach to High-Capacity Hydrogen Storage.

    Science.gov (United States)

    Tan, Xin; Kou, Liangzhi; Tahini, Hassan A; Smith, Sean C

    2015-11-01

    Electrical charging of graphitic carbon nitride nanosheets (g-C4 N3 and g-C3 N4 ) is proposed as a strategy for high-capacity and electrocatalytically switchable hydrogen storage. Using first-principle calculations, we found that the adsorption energy of H2 molecules on graphitic carbon nitride nanosheets is dramatically enhanced by injecting extra electrons into the adsorbent. At full hydrogen coverage, the negatively charged graphitic carbon nitride achieves storage capacities up to 6-7 wt %. In contrast to other hydrogen storage approaches, the storage/release occurs spontaneously once extra electrons are introduced or removed, and these processes can be simply controlled by switching on/off the charging voltage. Therefore, this approach promises both facile reversibility and tunable kinetics without the need of specific catalysts. Importantly, g-C4 N3 has good electrical conductivity and high electron mobility, which can be a very good candidate for electron injection/release. These predictions may prove to be instrumental in searching for a new class of high-capacity hydrogen storage materials. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. High capacity fiber optic sensor networks using hybrid multiplexing techniques and their applications

    Science.gov (United States)

    Sun, Qizhen; Li, Xiaolei; Zhang, Manliang; Liu, Qi; Liu, Hai; Liu, Deming

    2013-12-01

    Fiber optic sensor network is the development trend of fiber senor technologies and industries. In this paper, I will discuss recent research progress on high capacity fiber sensor networks with hybrid multiplexing techniques and their applications in the fields of security monitoring, environment monitoring, Smart eHome, etc. Firstly, I will present the architecture of hybrid multiplexing sensor passive optical network (HSPON), and the key technologies for integrated access and intelligent management of massive fiber sensor units. Two typical hybrid WDM/TDM fiber sensor networks for perimeter intrusion monitor and cultural relics security are introduced. Secondly, we propose the concept of "Microstructure-Optical X Domin Refecltor (M-OXDR)" for fiber sensor network expansion. By fabricating smart micro-structures with the ability of multidimensional encoded and low insertion loss along the fiber, the fiber sensor network of simple structure and huge capacity more than one thousand could be achieved. Assisted by the WDM/TDM and WDM/FDM decoding methods respectively, we built the verification systems for long-haul and real-time temperature sensing. Finally, I will show the high capacity and flexible fiber sensor network with IPv6 protocol based hybrid fiber/wireless access. By developing the fiber optic sensor with embedded IPv6 protocol conversion module and IPv6 router, huge amounts of fiber optic sensor nodes can be uniquely addressed. Meanwhile, various sensing information could be integrated and accessed to the Next Generation Internet.

  3. E- and W-band high-capacity hybrid fiber-wireless link

    DEFF Research Database (Denmark)

    Vegas Olmos, Juan José; Pang, Xiaodan; Tafur Monroy, Idelfonso

    2014-01-01

    In this paper we summarize the work conducted in our group in the area of E- and W-band optical high-capacity fiber-wireless links. We present performance evaluations of E- and W-band mm-wave signal generation using photonic frequency upconversion employing both VCSELs and ECLs, along with transm...... in mobile backhaul/fronthaul applications, dense distributed antenna systems and fiber-over-radio scenarios.......In this paper we summarize the work conducted in our group in the area of E- and W-band optical high-capacity fiber-wireless links. We present performance evaluations of E- and W-band mm-wave signal generation using photonic frequency upconversion employing both VCSELs and ECLs, along...... with transmission over different type of optical fibers and for a number of values for the wireless link distance. Hybrid wireless-optical links can be composed of mature and resilient technology available off-the-shelf, and provide functionalities that can add value to optical access networks, specifically...

  4. Review on anionic redox for high-capacity lithium- and sodium-ion batteries

    International Nuclear Information System (INIS)

    Zhao, Chenglong; Lu, Yaxiang; Hu, Yong-Sheng; Chen, Liquan; Wang, Qidi; Li, Baohua

    2017-01-01

    Rechargeable batteries, especially lithium-ion batteries, are now widely used as power sources for portable electronics and electric vehicles, but material innovations are still needed to satisfy the increasing demand for larger energy density. Recently, lithium- and sodium-rich electrode materials, including the A 2 MO 3 -family layered compounds (A  =  Li, Na; M  =  Mn 4+ , Ru 4+ , etc), have been extensively studied as potential high-capacity electrode materials for a cumulative cationic and anionic redox activity. Negatively charged oxide ions can potentially donate electrons to compensate for the absence of oxidable transition metals as a redox center to further increase the reversible capacity. Understanding and controlling the state-of-the-art anionic redox processes is pivotal for the design of advanced energy materials, highlighted in rechargeable batteries. Hence, experimental and theoretical approaches have been developed to consecutively study the diverting processes, states, and structures involved. In this review, we attempt to present a literature overview and provide insight into the reaction mechanism with respect to the anionic redox processes, proposing some opinions as target oriented. It is hoped that, through this discussion, the search for anionic redox electrode materials with high-capacity rechargeable batteries can be advanced, and practical applications realized as soon as possible. (topical review)

  5. Final Scientific/Technical Report for Low Cost, High Capacity Non- Intercalation Chemistry Automotive Cells

    Energy Technology Data Exchange (ETDEWEB)

    Berdichevsky, Gene [Sila Nanotechnologies, Inc., Alameda, CA (United States)

    2017-09-08

    Commercial Li-ion batteries typically use Ni- and Co-based intercalation cathodes. As the demand for improved performance from batteries increases, these cathode materials will no longer be able to provide the desired energy storage characteristics since they are currently approaching their theoretical limits. Conversion cathode materials are prime candidates for improvement of Li-ion batteries. On both a volumetric and gravimetric basis they have higher theoretical capacity than intercalation cathode materials. Metal fluoride (MFx) cathodes offer higher specific energy density and dramatically higher volumetric energy density. Challenges associated with metal fluoride cathodes were addressed through nanostructured material design and synthesis. A major goal of this project was to develop and demonstrate Li-ion cells based on Si-comprising anodes and metal fluoride (MFx) comprising cathodes. Pairing the high-capacity MFx cathode with a high-capacity anode, such as an alloying Si anode, allows for the highest possible energy density on a cell level. After facing and overcoming multiple material synthesis and electrochemical instability challenges, we succeeded in fabrication of MFx half cells with cycle stability in excess of 500 cycles (to 20% or smaller degradation) and full cells with MFx-based cathodes and Si-based anodes with cycle stability in excess of 200 cycles (to 20% or smaller degradation).

  6. Crack-resistant polyimide coating for high-capacity battery anodes

    Science.gov (United States)

    Li, Yingshun; Wang, Shuo; Lee, Pui-Kit; He, Jieqing; Yu, Denis Y. W.

    2017-10-01

    Electrode cracking is a serious problem that hinders the application of many next-generation high-capacity anode materials for lithium-ion batteries. Even though nano-sizing the material can reduce fracturing of individual particles, capacity fading is still observed due to large volume change and loss of contact in the electrode during lithium insertion and extraction. In this study, we design a crack-resistant high-modulus polyimide coating with high compressive strength which can hold multiple particles together during charge and discharge to maintain contact. The effectiveness of the coating is demonstrated on tin dioxide, a high-capacity large-volume-change material that undergoes both alloy and conversion reactions. The polyimide coating improves capacity retention of SnO2 from 80% to 100% after 80 cycles at 250 mA g-1. Stable capacity of 585 mAh g-1 can be obtained even at 500 mA g-1 after 300 cycles. Scanning electron microscopy and in-situ dilatometry confirm that electrode cracking is suppressed and thickness change is reduced with the coating. In addition, the chemically-stable polyimide film can separate the surface from direct contact with electrolyte, improving coulombic efficiency to ∼100%. We expect the novel strategy of suppressing electrode degradation with a crack-resistant coating can also be used for other alloy and conversion-based anodes.

  7. The sensory components of high-capacity iconic memory and visual working memory.

    Science.gov (United States)

    Bradley, Claire; Pearson, Joel

    2012-01-01

    EARLY VISUAL MEMORY CAN BE SPLIT INTO TWO PRIMARY COMPONENTS: a high-capacity, short-lived iconic memory followed by a limited-capacity visual working memory that can last many seconds. Whereas a large number of studies have investigated visual working memory for low-level sensory features, much research on iconic memory has used more "high-level" alphanumeric stimuli such as letters or numbers. These two forms of memory are typically examined separately, despite an intrinsic overlap in their characteristics. Here, we used a purely sensory paradigm to examine visual short-term memory for 10 homogeneous items of three different visual features (color, orientation and motion) across a range of durations from 0 to 6 s. We found that the amount of information stored in iconic memory is smaller for motion than for color or orientation. Performance declined exponentially with longer storage durations and reached chance levels after ∼2 s. Further experiments showed that performance for the 10 items at 1 s was contingent on unperturbed attentional resources. In addition, for orientation stimuli, performance was contingent on the location of stimuli in the visual field, especially for short cue delays. Overall, our results suggest a smooth transition between an automatic, high-capacity, feature-specific sensory-iconic memory, and an effortful "lower-capacity" visual working memory.

  8. Does visual short-term memory have a high-capacity stage?

    Science.gov (United States)

    Matsukura, Michi; Hollingworth, Andrew

    2011-12-01

    Visual short-term memory (VSTM) has long been considered a durable, limited-capacity system for the brief retention of visual information. However, a recent work by Sligte et al. (Plos One 3:e1699, 2008) reported that, relatively early after the removal of a memory array, a cue allowed participants to access a fragile, high-capacity stage of VSTM that is distinct from iconic memory. In the present study, we examined whether this stage division is warranted by attempting to corroborate the existence of an early, high-capacity form of VSTM. The results of four experiments did not support Sligte et al.'s claim, since we did not obtain evidence for VSTM retention that exceeded traditional estimates of capacity. However, performance approaching that observed in Sligte et al. can be achieved through extensive practice, providing a clear explanation for their findings. Our evidence favors the standard view of VSTM as a limited-capacity system that maintains a few object representations in a relatively durable form.

  9. Study on the flow nonuniformity in a high capacity Stirling pulse tube cryocooler

    Science.gov (United States)

    You, X.; Zhi, X.; Duan, C.; Jiang, X.; Qiu, L.; Li, J.

    2017-12-01

    High capacity Stirling-type pulse tube cryocoolers (SPTC) have promising applications in high temperature superconductive motor and gas liquefaction. However, with the increase of cooling capacity, its performance deviates from well-accepted one-dimensional model simulation, such as Sage and Regen, mainly due to the strong field nonuniformity. In this study, several flow straighteners placed at both ends of the pulse tube are investigated to improve the flow distribution. A two-dimensional model of the pulse tube based on the computational fluid dynamics (CFD) method has been built to study the flow distribution of the pulse tube with different flow straighteners including copper screens, copper slots, taper transition and taper stainless slot. A SPTC set-up which has more than one hundred Watts cooling power at 80 K has been built and tested. The flow straighteners mentioned above have been applied and tested. The results show that with the best flow straightener the cooling performance of the SPTC can be significantly improved. Both CFD simulation and experiment show that the straighteners have impacts on the flow distribution and the performance of the high capacity SPTC.

  10. The sensory components of high-capacity iconic memory and visual working memory

    Directory of Open Access Journals (Sweden)

    Claire eBradley

    2012-09-01

    Full Text Available Early visual memory can be split into two primary components: a high-capacity, short-lived iconic memory followed by a limited-capacity visual working memory that can last many seconds. Whereas a large number of studies have investigated visual working memory for low-level sensory features, much research on iconic memory has used more high-level alphanumeric stimuli such as letters or numbers. These two forms of memory are typically examined separately, despite an intrinsic overlap in their characteristics. Here, we used a purely sensory paradigm to examine visual short-term memory for 10 homogeneous items of 3 different visual features (colour, orientation and motion across a range of durations from 0 to 6 seconds. We found that the amount of information stored in iconic memory is smaller for motion than for colour or orientation. Performance declined exponentially with longer storage durations and reached chance levels after ~2 seconds. Further experiments showed that performance for the 10 items at 1 second was contingent on unperturbed attentional resources. In addition, for orientation stimuli, performance was contingent on the location of stimuli in the visual field, especially for short cue delays. Overall, our results suggest a smooth transition between an automatic, high-capacity, feature-specific sensory-iconic memory and an effortful ‘lower-capacity’ visual working memory.

  11. Safety Gear Decontamination Practices Among Florida Firefighters: Analysis of a Text-Based Survey Methodology.

    Science.gov (United States)

    Moore, Kevin J; Koru-Sengul, Tulay; Alvarez, Armando; Schaefer-Solle, Natasha; Harrison, Tyler R; Kobetz, Erin N; Caban-Martinez, Alberto J

    2018-02-01

    Despite the National Fire Protection Association (NFPA) 1851 Personal Protective Equipment Care and Maintenance guidelines, little is known about the routine cleaning of firefighter bunker gear. In collaboration with a large Florida firefighter union, a mobile phone text survey was administered, which included eight questions in an item logic format. In total, 250 firefighters participated in the survey of which 65% reported cleaning their bunker gear in the past 12 months. Approximately 32% ( n = 52) indicated that they had above average confidence in gear cleaning procedures. Arriving at a fire incident response was a significant predictor of gear cleaning in the 12 months preceding survey administration. Using mobile phone-based texting for periodic queries on adherence to NFPA cleaning guidelines and safety message distribution may assist firefighters to increase decontamination procedure frequency.

  12. EFFICIENCY OF FIRE-FIGHTING PROTECTION OBJECTS IN PROVISION OF FIRE SAFETY AT INDUSTRIAL ENTERPRISES

    Directory of Open Access Journals (Sweden)

    A. V. Zhovna

    2008-01-01

    Full Text Available The paper gives an analysis of economic results pertaining to organization of a system for fire-fighting protection of industrial enterprises in theRepublicofBelarus. Statistical data on operational conditions of technical means of fire-fighting protection, particularly, automatic systems for detection and extinguishing of fires, systems of internal fire-fighting water-supply.  Requirements and provisions  of normative and technical documents are thoroughly studied. Observance of these documents is to ensure the required level of  fire safety. On the basis of the obtained results concerning  economic analysis of efficiency optimization directions are defined for selection of technical means of fire-fighting protection at objects of industrial purpose.

  13. Firefighter's compressed air breathing system pressure vessel development program

    Science.gov (United States)

    Beck, E. J.

    1974-01-01

    The research to design, fabricate, test, and deliver a pressure vessel for the main component in an improved high-performance firefighter's breathing system is reported. The principal physical and performance characteristics of the vessel which were required are: (1) maximum weight of 9.0 lb; (2) maximum operating pressure of 4500 psig (charge pressure of 4000 psig); (3) minimum contained volume of 280 in. 3; (4) proof pressure of 6750 psig; (5) minimum burst pressure of 9000 psig following operational and service life; and (6) a minimum service life of 15 years. The vessel developed to fulfill the requirements described was completely sucessful, i.e., every category of performence was satisfied. The average weight of the vessel was found to be about 8.3 lb, well below the 9.0 lb specification requirement.

  14. Rope rescue in National fire-fighting and rescue system

    OpenAIRE

    SOCHACKI MARIAN

    2008-01-01

    Автор описывает организацию, функционирование и место системы спасения с высоты в Государственной спасательно-гасящей системе.The author describes organization, working and place of rope rescue in National Firefighting and Rescue System (KSRG).

  15. Dietary Preferences and Nutritional Information Needs Among Career Firefighters in the United States

    OpenAIRE

    Yang, Justin; Farioli, Andrea; Korre, Maria; Kales, Stefanos N.

    2015-01-01

    Background: Considerable cardiovascular disease and cancer risk among firefighters are attributable to excess adiposity. Robust evidence confirms strong relationships between dietary patterns and the risk of chronic disease. Dietary modification is more likely to be effective when the strategy is appealing and addresses knowledge gaps. Objective: To assess career firefighters' diet practices and information needs, compare the relative appeal of proposed diet plans, and examine how these vary ...

  16. Surviving Rates of Graphs with Bounded Treewidth for the Firefighter Problem

    DEFF Research Database (Denmark)

    Cai, Leizhen; Cheng, Yongxi; Verbin, Elad

    2010-01-01

    The firefighter problem is the following discrete-time game on a graph. Initially, a fire starts at a vertex of the graph. In each round, a firefighter protects one vertex not yet on fire, and then the fire spreads to all unprotected neighbors of the vertices on fire. The objective of the firefig...... of Cai and Wang [SIAM J. Discrete Math., 23 (2009), pp. 1814-1826] in affirmative....

  17. Accuracy of Body Mass Index-defined Obesity Status in US Firefighters

    OpenAIRE

    Jitnarin, Nattinee; Poston, Walker S.C.; Haddock, Christopher K.; Jahnke, Sara A.; Day, Rena S.

    2014-01-01

    Obesity is a significant problem affecting United States (US) firefighters. While body mass index (BMI) is widely used to diagnose obesity, its use for this occupational group has raised concerns about validity. We examined rates and types of misclassification of BMI-based obesity status compared to body fat percentage (BF%) and waist circumference (WC). Male career firefighters (N = 994) from 20 US departments completed all three body composition assessments. Mean BMI, BF%, and WC were 29 kg...

  18. Anxiety sensitivity and suicide risk among firefighters: A test of the depression-distress amplification model.

    Science.gov (United States)

    Stanley, Ian H; Smith, Lia J; Boffa, Joseph W; Tran, Jana K; Schmidt, N Brad; Joiner, Thomas E; Vujanovic, Anka A

    2018-04-07

    Firefighters represent an occupational group at increased suicide risk. How suicidality develops among firefighters is poorly understood. The depression-distress amplification model posits that the effects of depression symptoms on suicide risk will be intensified in the context of anxiety sensitivity (AS) cognitive concerns. The current study tested this model among firefighters. Overall, 831 firefighters participated (mean [SD] age = 38.37 y [8.53 y]; 94.5% male; 75.2% White). The Center for Epidemiologic Studies Depression Scale (CES-D), Anxiety Sensitivity Index-3 (ASI-3), and Suicidal Behaviors Questionnaire-Revised (SBQ-R) were utilized to assess for depression symptoms, AS concerns (cognitive, physical, social), and suicide risk, respectively. Linear regression interaction models were tested. The effects of elevated depression symptoms on increased suicide risk were augmented when AS cognitive concerns were also elevated. Unexpectedly, depression symptoms also interacted with AS social concerns; however, consistent with expectations, depression symptoms did not interact with AS physical concerns in the prediction of suicide risk. In the context of elevated depression symptoms, suicide risk is potentiated among firefighters reporting elevated AS cognitive and AS social concerns. Findings support and extend the depression-distress amplification model of suicide risk within a sample of firefighters. Interventions that successfully impact AS concerns may, in turn, mitigate suicide risk among this at-risk population. Copyright © 2018 Elsevier Inc. All rights reserved.

  19. Exploring Occupational and Behavioral Risk Factors for Obesity in Firefighters: A Theoretical Framework and Study Design

    Directory of Open Access Journals (Sweden)

    BongKyoo Choi

    2011-12-01

    Full Text Available Firefighters and police officers have the third highest prevalence of obesity among 41 male occupational groups in the United States (US. However, few studies have examined the relationship of firefighter working conditions and health behaviors with obesity. This paper presents a theoretical framework describing the relationship between working conditions, health behaviors, and obesity in firefighters. In addition, the paper describes a detailed study plan for exploring the role of occupational and behavioral risk factors in the development of obesity in firefighters enrolled in the Orange County Fire Authority Wellness Fitness Program. The study plan will be described with emphasis on its methodological merits: adopting a participatory action research approach, developing a firefighter-specific work and health questionnaire, conducting both a cross-sectional epidemiological study using the questionnaire and a sub-study to assess the validity of the questionnaire with dietary intake and physical activity measures, and evaluating the strengths and weaknesses of the body mass index as an obesity measure in comparison to skinfold-based percent body fat. The study plan based on a theoretical framework can be an essential first step for establishing effective intervention programs for obesity among professional and voluntary firefighters.

  20. Occupational stress and suicidality among firefighters: Examining the buffering role of distress tolerance.

    Science.gov (United States)

    Stanley, Ian H; Boffa, Joseph W; Smith, Lia J; Tran, Jana K; Schmidt, N Brad; Joiner, Thomas E; Vujanovic, Anka A

    2018-05-24

    Past research indicates that firefighters are at increased risk for suicide. Firefighter-specific occupational stress may contribute to elevated suicidality. Among a large sample of firefighters, this study examined if occupational stress is associated with multiple indicators of suicide risk, and whether distress tolerance, the perceived and/or actual ability to endure negative emotional or physical states, attenuates these associations. A total of 831 firefighters participated (mean [SD] age = 38.37y[8.53y]; 94.5% male; 75.2% White). The Sources of Occupational Stress-14 (SOOS-14), Distress Tolerance Scale (DTS), and Suicidal Behaviors Questionnaire-Revised (SBQ-R) were utilized to examine firefighter-specific occupational stress, distress tolerance, and suicidality, respectively. Consistent with predictions, occupational stress interacted with distress tolerance, such that the effects of occupational stress on suicide risk, broadly, as well as lifetime suicide threats and current suicidal intent, specifically, were attenuated at high levels of distress tolerance. Distress tolerance may buffer the effects of occupational stress on suicidality among firefighters. Pending replication, findings suggest that distress tolerance may be a viable target for suicide prevention initiatives within the fire service. Copyright © 2018 Elsevier B.V. All rights reserved.

  1. Occupational Exposure to Polycyclic Aromatic Hydrocarbon of Wildland Firefighters at Prescribed and Wildland Fires.

    Science.gov (United States)

    Navarro, Kathleen M; Cisneros, Ricardo; Noth, Elizabeth M; Balmes, John R; Hammond, S Katharine

    2017-06-06

    Wildland firefighters suppressing wildland fires or conducting prescribed fires work long shifts during which they are exposed to high levels of wood smoke with no respiratory protection. Polycyclic aromatic hydrocarbons (PAHs) are hazardous air pollutants formed during incomplete combustion. Exposure to PAHs was measured for 21 wildland firefighters suppressing two wildland fires and 4 wildland firefighters conducting prescribed burns in California. Personal air samples were actively collected using XAD4-coated quartz fiber filters and XAD2 sorbent tubes. Samples were analyzed for 17 individual PAHs through extraction with dichloromethane and gas chromatograph-mass spectrometer analysis. Naphthalene, retene, and phenanthrene were consistently the highest measured PAHs. PAH concentrations were higher at wildland fires compared to prescribed fires and were highest for firefighters during job tasks that involve the most direct contact with smoke near an actively burning wildland fire. Although concentrations did not exceed current occupational exposure limits, wildland firefighters are exposed to PAHs not only on the fire line at wildland fires, but also while working prescribed burns and while off-duty. Characterization of occupational exposures from wildland firefighting is important to understand better any potential long-term health effects.

  2. High capacity argon extraction and purification system. [Suitable for age estimation of rocks

    Energy Technology Data Exchange (ETDEWEB)

    Balogh, K; Morik, Gy [Magyar Tudomanyos Akademia Atommag Kutato Intezete, Debrecen

    1979-01-01

    A high capacity metal-glass argon extraction and purification system has been developed for K/Ar dating of geologic materials. A set of samples can be loaded simultaneously and degassed in turn in the system by high frequency induction heating in a molybdenum crucible. The argon purification is carried out by titanium sponge, molecular sieve, copper oxide and glass and charcoal filled traps cooled by liquid nitrogen. The /sup 38/Ar spike and the atmospheric argon used for calibrating the mass spectrometer are dispensed by a gas-pipette system. 80-120 minutes after starting the degassing of the sample, the purified argon can be introduced into the mass spectrometer; the gettering materials regenerate in 1-5 hours, thus 1-3 samples may be analysed a day. The atmospheric argon inflow during an experimental process is less than 5x10/sup -8/ cc STP.

  3. Design of a Two-stage High-capacity Stirling Cryocooler Operating below 30K

    Science.gov (United States)

    Wang, Xiaotao; Dai, Wei; Zhu, Jian; Chen, Shuai; Li, Haibing; Luo, Ercang

    The high capacity cryocooler working below 30K can find many applications such as superconducting motors, superconducting cables and cryopump. Compared to the GM cryocooler, the Stirling cryocooler can achieve higher efficiency and more compact structure. Because of these obvious advantages, we have designed a two stage free piston Stirling cryocooler system, which is driven by a moving magnet linear compressor with an operating frequency of 40 Hz and a maximum 5 kW input electric power. The first stage of the cryocooler is designed to operate in the liquid nitrogen temperature and output a cooling power of 100 W. And the second stage is expected to simultaneously provide a cooling power of 50 W below the temperature of 30 K. In order to achieve the best system efficiency, a numerical model based on the thermoacoustic model was developed to optimize the system operating and structure parameters.

  4. Key technology studies of GY-20 and GY-40 High-capacity cobalt-60 transport casks

    International Nuclear Information System (INIS)

    Liu Huifang; Zhang Xin

    2012-01-01

    GY-20 and GY-40 high-capacity cobalt-60 transport casks are used to transport cobalt-60 industrial irradiators and cobalt-60 bundles. The radioactive contents have special features of high-activity and high residual heat, so only a few countries such as Canada, England and Russia have design capacity. The key technologies and corresponding solutions were studied for the design and manufacture of the cask taking into account the structural, thermal, mechanics and shield requests. A series of tests prove that the cask structure design, design criteria for lead coating structure and quality control measurements are reasonable and effective, and the cask shield integrity can be ensured for all conditions. The casks have ability to transport high-activity sealed sources safely, and the design of cask satisfies the requirement of design code and standard. It can provide reference for other B type package. (authors)

  5. Development of high-capacity nickel-metal hydride batteries using superlattice hydrogen-absorbing alloys

    Science.gov (United States)

    Yasuoka, Shigekazu; Magari, Yoshifumi; Murata, Tetsuyuki; Tanaka, Tadayoshi; Ishida, Jun; Nakamura, Hiroshi; Nohma, Toshiyuki; Kihara, Masaru; Baba, Yoshitaka; Teraoka, Hirohito

    New R-Mg-Ni (R: rare earths) superlattice alloys with higher-capacity and higher-durability than the conventional Mm-Ni alloys with CaCu 5 structure have been developed. The oxidation resistibility of the superlattice alloys has been improved by optimizing the alloy composition by such as substituting aluminum for nickel and optimizing the magnesium content in order to prolong the battery life. High-capacity nickel-metal hydride batteries for the retail market, the Ni-MH2500/900 series (AA size type 2500 mAh, AAA size type 900 mAh), have been developed and commercialized by using an improved superlattice alloy for negative electrode material.

  6. High-Capacity Hybrid Optical Fiber-Wireless Communications Links in Access Networks

    DEFF Research Database (Denmark)

    Pang, Xiaodan

    of broadband services access. To realize the seamless convergence between the two network segments, the lower capacity of wireless systems need to be increased to match the continuously increasing bandwidth of fiber-optic systems. The research works included in this thesis are devoted to experimental...... investigations of photonic-wireless links with record high capacities to fulfill the requirements of next generation hybrid optical fiber-wireless access networks. The main contributions of this thesis have expanded the state-of-the-art in two main areas: high speed millimeter-wave (mm-wave) communication links......Integration between fiber-optic and wireless communications systems in the "last mile" access networks is currently considered as a promising solution for both service providers and users, in terms of minimizing deployment cost, shortening upgrading period and increasing mobility and flexibility...

  7. A micro-structured Si-based electrodes for high capacity electrical double layer capacitors

    International Nuclear Information System (INIS)

    Krikscikas, Valdas; Oguchi, Hiroyuki; Hara, Motoaki; Kuwano, Hiroki; Yanazawa, Hiroshi

    2014-01-01

    We challenged to make basis for Si electrodes of electric double layer capacitors (EDLC) used as a power source of micro-sensor nodes. Mcroelectromechanical systems (MEMS) processes were successfully introduced to fabricate micro-structured Si-based electrodes to obtain high surface area which leads to high capacity of EDLCs. Study of fundamental properties revealed that the microstructured electrodes benefit from good wettability to electrolytes, but suffer from electric resistance. We found that this problem can be solved by metal-coating of the electrode surface. Finally we build an EDLC consisting of Au-coated micro-structured Si electrodes. This EDLC showed capacity of 14.3 mF/cm 2 , which is about 530 times larger than that of an EDLC consisting of flat Au electrodes

  8. An FDMA system concept for 30/20 GHz high capacity domestic satellite service

    Science.gov (United States)

    Berk, G.; Jean, P. N.; Rotholz, E.; White, B. E.

    1982-01-01

    The paper summarizes a feasibility study of a multibeam FDMA satellite system operating in the 30/20 GHz band. The system must accommodate a very high volume of traffic within the restrictions of a 5 kW solar cell array and a 2.5 GHz bandwidth. Multibeam satellite operation reduces the DC power demand and allows reuse of the available bandwidth. Interferences among the beams are brought to acceptable levels by appropriate frequency assignments. A transponder design is presented; it is greatly simplified by the application of a regional concept. System analysis shows that MSK modulation is appropriate for a high-capacity system because it conserves the frequency spectrum. Rain attenuation, a serious problem in this frequency band, is combatted with sufficient power margins and with coding. Link budgets, cost analysis, and weight and power calculations are also discussed. A satellite-routed FDMA system compares favorably in performance and cost with a satellite-switched TDMA system.

  9. Operating experience with a high capacity helium pump under supercritical conditions

    International Nuclear Information System (INIS)

    Lehmann, W.; Minges, J.

    1984-01-01

    This chapter discusses the development and testing of a high-capacity piston pump to provide forced cooling for large superconducting magnets. The pump is a three cylinder, vertically arranged single-acting piston pump equipped with a frequency controlled three-phase geared motor operating at room temperature. The pump is capable of delivering up to 150 g/s at a maximum speed of 310 rpm and under the inlet conditions of 4 bar/4.5 K. No decline was noticed in delivery head and efficiencies during more than 560 hours of operation. It is concluded that the pump satisfies all requirements for circulating large mass flows across great pressure differences as needed (e.g. in fusion magnet design)

  10. Porous carbon with small mesoporesas an ultra-high capacity adsorption medium

    Science.gov (United States)

    Gao, Biaofeng; Zhou, Haitao; Chen, De; Yang, Jianhong

    2017-10-01

    Resins (732-type), abundant and inexpensive resources were used to prepare porous carbon with small mesopores (CSM) by carbonization and post-chemical-activation with potassium hydroxide (KOH). The N2 adsorption measurements revealed that CSM had high surface areas (1776.5 m2 g-1), large pore volumes (1.10 cm3 g-1), and nearly optimal narrow small mesopore sizes ranging from 2 to 7 nm. CSM was used as adsorbent to investigate the adsorption behavior for Rhodamine B (RhB). Due to the optimal pore size distributions (PSD), intensive-stacking interaction, S-doped, and electrostatic attraction, the CSM exhibited an ultra-high-capacity of 1590 mg g-1 for RhB in aqueous solutions.

  11. Flower-like SnO2/graphene composite for high-capacity lithium storage

    International Nuclear Information System (INIS)

    Liu Hongdong; Huang Jiamu; Li Xinlu; Liu Jia; Zhang Yuxin; Du Kun

    2012-01-01

    Flower-like SnO 2 /graphene composite is synthesized by a simple hydrothermal method for high-capacity lithium storage. The as-prepared products are characterized by XRD, FTIR, FESEM, TGA and Nitrogen adsorption/desorption. The electrochemical performance of the flower-like SnO 2 /graphene composite is measured by cyclic voltammetry and galvanostatic charge/discharge cycling. The results show that the flower-like SnO 2 nanorod clusters are 800 nm in size and homogeneously adhere on graphene sheets. The flower-like SnO 2 /graphene composite displays superior Li-battery performance with large reversible capacity, excellent cyclic performance and good rate capability.

  12. Development of high-capacity nickel-metal hydride batteries using superlattice hydrogen-absorbing alloys

    International Nuclear Information System (INIS)

    Yasuoka, Shigekazu; Magari, Yoshifumi; Murata, Tetsuyuki; Tanaka, Tadayoshi; Ishida, Jun; Nakamura, Hiroshi; Nohma, Toshiyuki; Kihara, Masaru; Baba, Yoshitaka; Teraoka, Hirohito

    2006-01-01

    New R-Mg-Ni (R: rare earths) superlattice alloys with higher-capacity and higher-durability than the conventional Mm-Ni alloys with CaCu 5 structure have been developed. The oxidation resistibility of the superlattice alloys has been improved by optimizing the alloy composition by such as substituting aluminum for nickel and optimizing the magnesium content in order to prolong the battery life. High-capacity nickel-metal hydride batteries for the retail market, the Ni-MH2500/900 series (AA size type 2500mAh, AAA size type 900mAh), have been developed and commercialized by using an improved superlattice alloy for negative electrode material. alized by using an improved superlattice alloy for negative electrode material. (author)

  13. Durability testing of the high-capacity GA-4/GA-9 trailer

    International Nuclear Information System (INIS)

    Zimmer, A.

    1993-01-01

    General Atomics (GA) is under contract to the US Department of Energy (DOE), Idaho Field Office, to develop two legal-weight truck from-reactor spent-fuel shipping casks with trailers. GA is developing these high capacity transport systems to support the Office of Civilian Radioactive Waste Management's (OCRWM) mission to transport spent fuel from reactors to a permanent disposal site. GA's goal is to maximize the number of fuel assemblies that the transport system can safely carry. The GA-4 Cask is being designed to transport four pressurized-water-reactor (PWR) spent-fuel assemblies, and the GA-9 Cask is being designed to transport nine boiling-water-reactor (BWR) spent-fuel assemblies. The use of these high-capacity transport systems will have a large benefit to-public safety since the number of legal-weight truck shipments will be reduced by at least a factor of four over existing spent-fuel shipping cask systems. Achieving these capacities requires that the weight of each component of the transport system. i.e., cask, trailer and tractor, be minimized. The weight of the trailer is of particular importance. With a high load-to-weight ratio, the durability and reliability of the trailer become significant factors in the success of the transport system. In order to verify that the trailer design will meet the durability and performance requirements to safely transport spent-fuel, GA has planned an extensive testing program. The testing program includes non-destructive examination (NDE) of the trailer welds, operational testing, a static load test, an over-the-road performance test, and a test to verify the durability of the trailer up to its 1,000,000-mile design life. Since a prototype cask will not be available for the testing, GA designed and built a dummy payload that simulates the correct weight distribution and approximates the dynamic response of the prototype cask

  14. High-capacity quantum secure direct communication with two-photon six-qubit hyperentangled states

    Science.gov (United States)

    Wu, FangZhou; Yang, GuoJian; Wang, HaiBo; Xiong, Jun; Alzahrani, Faris; Hobiny, Aatef; Deng, FuGuo

    2017-12-01

    This study proposes the first high-capacity quantum secure direct communication (QSDC) with two-photon six-qubit hyper-entangled Bell states in two longitudinal momentum and polarization degrees of freedom (DOFs) of photon pairs, which can be generated using two 0.5 mm-thick type-I β barium borate crystal slabs aligned one behind the other and an eight-hole screen. The secret message can be independently encoded on the photon pairs with 64 unitary operations in all three DOFs. This protocol has a higher capacity than previous QSDC protocols because each photon pair can carry 6 bits of information, not just 2 or 4 bits. Our QSDC protocol decreases the influence of decoherence from environment noise by exploiting the decoy photons to check the security of the transmission of the first photon sequence. Compared with two-way QSDC protocols, our QSDC protocol is immune to an attack by an eavesdropper using Trojan horse attack strategies because it is a one-way quantum communication. The QSDC protocol has good applications in the future quantum communication because of all these features.

  15. High-capacity, high-strength trailer designs for the GA-4/GA-9 casks

    International Nuclear Information System (INIS)

    Rickard, N.D.; Kissinger, J.A.; Taylor, C.; Zimmer, A.

    1991-01-01

    General Atomics (GA) is developing final designs for two dedicated legal-weight trailers to transport the GA-4 and GA-9 Spent-Fuel Casks. The basic designs for these high-capacity, high-strength trailers are essentially identical except for small modifications to account for the differences in cask geometry. The authors are designing both trailers to carry a 55,000 lb (24,900 kg) payload and to withstand a 2.5 g vertical design load. The GA-4 and GA-9 trailers are designed for significantly higher loads than are typical commercial semitrailers, which are designed to loads in the range of 1.7 to 2.0 g. To meet the federal gross vehicle weight limit for legal-weight trucks, GA has set a target design weight for the trailers of 9000 lb (4080 kg). This weight includes the personnel barrier, cask tiedowns, and impact limiter removal and storage system. Based on the preliminary trailer designs, the final design weight will to be very close to this target weight

  16. High-capacity method for hiding data in the discrete cosine transform domain

    Science.gov (United States)

    Qazanfari, Kazem; Safabakhsh, Reza

    2013-10-01

    Steganography is the art and science of hiding data in different media such as texts, audios, images, and videos. Data hiding techniques are generally divided into two groups: spatial and frequency domain techniques. Spatial domain methods generally have low security and, as a result, are less attractive to researchers. Discrete cosine transform (DCT) is the most common transform domain used in steganography and JPEG compression. Since a large number of the DCT coefficients of JPEG images are zero, the capacity of DCT domain-based steganography methods is not very high. We present a high-capacity method for hiding messages in the DCT domain. We describe the method in two classes where the receiver has and where the receiver does not have the cover image. In each class, we consider three cases for each coefficient. By considering n coefficients, there are 3n different situations. The method embeds ⌊log2 3n⌋ bits in these n coefficients. We show that the maximum reachable capacity by our method is 58% higher than the other general steganography methods. Experimental results show that the histogram-based steganalysis methods cannot detect the stego images produced by the proposed method while the capacity is increased significantly.

  17. Carbon Nanofiber/3D Nanoporous Silicon Hybrids as High Capacity Lithium Storage Materials.

    Science.gov (United States)

    Park, Hyeong-Il; Sohn, Myungbeom; Kim, Dae Sik; Park, Cheolho; Choi, Jeong-Hee; Kim, Hansu

    2016-04-21

    Carbon nanofiber (CNF)/3D nanoporous (3DNP) Si hybrid materials were prepared by chemical etching of melt-spun Si/Al-Cu-Fe alloy nanocomposites, followed by carbonization using a pitch. CNFs were successfully grown on the surface of 3DNP Si particles using residual Fe impurities after acidic etching, which acted as a catalyst for the growth of CNFs. The resulting CNF/3DNP Si hybrid materials showed an enhanced cycle performance up to 100 cycles compared to that of the pristine Si/Al-Cu-Fe alloy nanocomposite as well as that of bare 3DNP Si particles. These results indicate that CNFs and the carbon coating layer have a beneficial effect on the capacity retention characteristics of 3DNP Si particles by providing continuous electron-conduction pathways in the electrode during cycling. The approach presented here provides another way to improve the electrochemical performances of porous Si-based high capacity anode materials for lithium-ion batteries. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. State Violence and Oppositional Protest in High-Capacity Authoritarian Regimes

    Directory of Open Access Journals (Sweden)

    Hank Johnston

    2012-05-01

    Full Text Available This examination of the mobilization-repression nexus in high-capacity authoritarian regimes draws on examples from China, Russia, Iran, and several Middle Eastern states to develop a framework for analyzing state violence and how political oppositions are organized. The study examines middle and low levels of state violence, the provincial and municipal organization of party and regime, and the police, private militias, and thugs as low-level enforcers, and focuses on: (1 the complexity of the state’s apparatus of repression and control and how different levels exercise different forms of violence against activists; (2 the creativity of the opposition’s actions to voice its demands and avoid repression and surveillance; and (3 the recursive relationship between the two, a dark dance between state and opposition with high stakes for both. Hierarchical analysis at national, provincial, and local levels, and lateral analysis across these levels, where elite interests frequently diverge, show that intersections and gaps on both axes can create lapses in social control and openings the opposition. These free spaces of speech and innovative action give rise to novel ways to keep oppositional sentiments in the public forum. The article offers several propositions for analyzing repression and state violence at various levels, and, similarly, the various ways that these free spaces occur.

  19. Study on a high capacity two-stage free piston Stirling cryocooler working around 30 K

    Science.gov (United States)

    Wang, Xiaotao; Zhu, Jian; Chen, Shuai; Dai, Wei; Li, Ke; Pang, Xiaomin; Yu, Guoyao; Luo, Ercang

    2016-12-01

    This paper presents a two-stage high-capacity free-piston Stirling cryocooler driven by a linear compressor to meet the requirement of the high temperature superconductor (HTS) motor applications. The cryocooler system comprises a single piston linear compressor, a two-stage free piston Stirling cryocooler and a passive oscillator. A single stepped displacer configuration was adopted. A numerical model based on the thermoacoustic theory was used to optimize the system operating and structure parameters. Distributions of pressure wave, phase differences between the pressure wave and the volume flow rate and different energy flows are presented for a better understanding of the system. Some characterizing experimental results are presented. Thus far, the cryocooler has reached a lowest cold-head temperature of 27.6 K and achieved a cooling power of 78 W at 40 K with an input electric power of 3.2 kW, which indicates a relative Carnot efficiency of 14.8%. When the cold-head temperature increased to 77 K, the cooling power reached 284 W with a relative Carnot efficiency of 25.9%. The influences of different parameters such as mean pressure, input electric power and cold-head temperature are also investigated.

  20. On-demand high-capacity ride-sharing via dynamic trip-vehicle assignment.

    Science.gov (United States)

    Alonso-Mora, Javier; Samaranayake, Samitha; Wallar, Alex; Frazzoli, Emilio; Rus, Daniela

    2017-01-17

    Ride-sharing services are transforming urban mobility by providing timely and convenient transportation to anybody, anywhere, and anytime. These services present enormous potential for positive societal impacts with respect to pollution, energy consumption, congestion, etc. Current mathematical models, however, do not fully address the potential of ride-sharing. Recently, a large-scale study highlighted some of the benefits of car pooling but was limited to static routes with two riders per vehicle (optimally) or three (with heuristics). We present a more general mathematical model for real-time high-capacity ride-sharing that (i) scales to large numbers of passengers and trips and (ii) dynamically generates optimal routes with respect to online demand and vehicle locations. The algorithm starts from a greedy assignment and improves it through a constrained optimization, quickly returning solutions of good quality and converging to the optimal assignment over time. We quantify experimentally the tradeoff between fleet size, capacity, waiting time, travel delay, and operational costs for low- to medium-capacity vehicles, such as taxis and van shuttles. The algorithm is validated with ∼3 million rides extracted from the New York City taxicab public dataset. Our experimental study considers ride-sharing with rider capacity of up to 10 simultaneous passengers per vehicle. The algorithm applies to fleets of autonomous vehicles and also incorporates rebalancing of idling vehicles to areas of high demand. This framework is general and can be used for many real-time multivehicle, multitask assignment problems.

  1. Fast and simple high-capacity quantum cryptography with error detection

    Science.gov (United States)

    Lai, Hong; Luo, Ming-Xing; Pieprzyk, Josef; Zhang, Jun; Pan, Lei; Li, Shudong; Orgun, Mehmet A.

    2017-04-01

    Quantum cryptography is commonly used to generate fresh secure keys with quantum signal transmission for instant use between two parties. However, research shows that the relatively low key generation rate hinders its practical use where a symmetric cryptography component consumes the shared key. That is, the security of the symmetric cryptography demands frequent rate of key updates, which leads to a higher consumption of the internal one-time-pad communication bandwidth, since it requires the length of the key to be as long as that of the secret. In order to alleviate these issues, we develop a matrix algorithm for fast and simple high-capacity quantum cryptography. Our scheme can achieve secure private communication with fresh keys generated from Fibonacci- and Lucas- valued orbital angular momentum (OAM) states for the seed to construct recursive Fibonacci and Lucas matrices. Moreover, the proposed matrix algorithm for quantum cryptography can ultimately be simplified to matrix multiplication, which is implemented and optimized in modern computers. Most importantly, considerably information capacity can be improved effectively and efficiently by the recursive property of Fibonacci and Lucas matrices, thereby avoiding the restriction of physical conditions, such as the communication bandwidth.

  2. High-capacity, high-strength trailer designs for the GA-4/GA-9 Casks

    International Nuclear Information System (INIS)

    Kissinger, J.A.; Rickard, N.D.; Taylor, C.; Zimmer, A.

    1991-01-01

    General Atomics (GA) is developing final designs for two dedicated legal-weight trailers to transport the GA-4 and GA-9 Spent-Fuel Casks. The basic designs for these high-capacity, high-strength trailers are essentially identical except for small modifications to account for the differences in cask geometry. We are designing both trailers to carry a 55,000 lb (24,900 kg) payload and to withstand a 2.5 g vertical design load. The GA-4 and GA-9 trailers are designed for significantly higher loads than are typical commercial semitrailers, which are designed to loads in the range of 1.7 to 2.0 g. To meet the federal gross vehicle weight limit for legal-weight trucks, GA has set a target design weight for the trailers of 9000 lb (4080 kg). This weight includes the personnel barrier, cask tiedowns, and impact limiter removal and storage system. Based on the preliminary trailer designs, the final design weight is expected to be very close to this target weight. 3 refs., 3 figs

  3. High capacity for extracellular acid-base regulation in the air-breathing fish Pangasianodon hypophthalmus.

    Science.gov (United States)

    Damsgaard, Christian; Gam, Le Thi Hong; Tuong, Dang Diem; Thinh, Phan Vinh; Huong Thanh, Do Thi; Wang, Tobias; Bayley, Mark

    2015-05-01

    The evolution of accessory air-breathing structures is typically associated with reduction of the gills, although branchial ion transport remains pivotal for acid-base and ion regulation. Therefore, air-breathing fishes are believed to have a low capacity for extracellular pH regulation during a respiratory acidosis. In the present study, we investigated acid-base regulation during hypercapnia in the air-breathing fish Pangasianodon hypophthalmus in normoxic and hypoxic water at 28-30°C. Contrary to previous studies, we show that this air-breathing fish has a pronounced ability to regulate extracellular pH (pHe) during hypercapnia, with complete metabolic compensation of pHe within 72 h of exposure to hypoxic hypercapnia with CO2 levels above 34 mmHg. The high capacity for pHe regulation relies on a pronounced ability to increase levels of HCO3(-) in the plasma. Our study illustrates the diversity in the physiology of air-breathing fishes, such that generalizations across phylogenies may be difficult. © 2015. Published by The Company of Biologists Ltd.

  4. Fast and simple high-capacity quantum cryptography with error detection.

    Science.gov (United States)

    Lai, Hong; Luo, Ming-Xing; Pieprzyk, Josef; Zhang, Jun; Pan, Lei; Li, Shudong; Orgun, Mehmet A

    2017-04-13

    Quantum cryptography is commonly used to generate fresh secure keys with quantum signal transmission for instant use between two parties. However, research shows that the relatively low key generation rate hinders its practical use where a symmetric cryptography component consumes the shared key. That is, the security of the symmetric cryptography demands frequent rate of key updates, which leads to a higher consumption of the internal one-time-pad communication bandwidth, since it requires the length of the key to be as long as that of the secret. In order to alleviate these issues, we develop a matrix algorithm for fast and simple high-capacity quantum cryptography. Our scheme can achieve secure private communication with fresh keys generated from Fibonacci- and Lucas- valued orbital angular momentum (OAM) states for the seed to construct recursive Fibonacci and Lucas matrices. Moreover, the proposed matrix algorithm for quantum cryptography can ultimately be simplified to matrix multiplication, which is implemented and optimized in modern computers. Most importantly, considerably information capacity can be improved effectively and efficiently by the recursive property of Fibonacci and Lucas matrices, thereby avoiding the restriction of physical conditions, such as the communication bandwidth.

  5. Li2C2, a High-Capacity Cathode Material for Lithium Ion Batteries.

    Science.gov (United States)

    Tian, Na; Gao, Yurui; Li, Yurong; Wang, Zhaoxiang; Song, Xiaoyan; Chen, Liquan

    2016-01-11

    As a typical alkaline earth metal carbide, lithium carbide (Li2C2) has the highest theoretical specific capacity (1400 mA h g(-1)) among all the reported lithium-containing cathode materials for lithium ion batteries. Herein, the feasibility of using Li2C2 as a cathode material was studied. The results show that at least half of the lithium can be extracted from Li2C2 and the reversible specific capacity reaches 700 mA h g(-1). The C≡C bond tends to rotate to form C4 (C≡C⋅⋅⋅C≡C) chains during lithium extraction, as indicated with the first-principles molecular dynamics (FPMD) simulation. The low electronic and ionic conductivity are believed to be responsible for the potential gap between charge and discharge, as is supported with density functional theory (DFT) calculations and Arrhenius fitting results. These findings illustrate the feasibility to use the alkali and alkaline earth metal carbides as high-capacity electrode materials for secondary batteries. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. High-capacity NO2 denuder systems operated at various temperatures (298-473 K).

    Science.gov (United States)

    Wolf, Jan-Christoph; Niessner, Reinhard

    2012-12-01

    In this study, we investigated several coatings for high-temperature, high-capacity, and high-efficiency denuder-based NO(2) removal, with the scope to face the harsh conditions and requirements of automotive exhaust gas sampling. As first coating, we propose a potassium iodide (KI)/polyethylene glycol coating with a high removal efficiency (ε > 98%) for about 2 h and 50 ppm NO(2) at room temperature (298 K). At elevated temperatures (423 K), the initial capacity (100 ppmh) is decreased to 15 ppmh. Furthermore, this is the first proposal of the ionic liquid methyl-butyl-imidazolium iodide ([BMIm(+)][I(-)]) as denuder coating material. At room temperature, this ionic liquid exhibits far greater capacity (300 ppmh) and NO(2) removal efficiency (ε > 99.9%) than KI. Nevertheless, KI exhibits a slightly (~10%) higher capacity at elevated temperatures than [BMIm(+)][I(-)]. Both coatings presented are suitable for applications requiring selective denuding of NO(2) at temperatures up to 423 K.

  7. High-capacity transport, floor area ratio and its relationship with urbanization of metropolitan areas

    Energy Technology Data Exchange (ETDEWEB)

    Carvalho da Costa, B.L. de; Carvalho da Costa, F.B. de

    2016-07-01

    Most of the world’s population lives in urban areas (54%). Near 42% of the global urban population live in cities with more than 1 million inhabitants, where problems associated with urban sprawl such as informal settlement, social-economic changes, environmental degradation and deficient high-capacity transport (HCT) systems are common. Meanwhile, urbanization and its associated transportation infrastructure define the relationship between city and countryside, between the city’s inner core and the periphery, between the citizen and his right to move. This article discusses and presents an overview about the relationship between the planning and extension of HCT systems and urban planning, (in the figure of the floor-area ratio - FAR- prescribed in regulations). The methodological approach consists of drawing a conceptual framework and studying 33 different cities of metropolitan areas on five continents. It’s noticed that areas in cities with a high construction potential but with an insufficient HCT negatively influence in urban mobility and hence the right to the city. We consider right to the city the various social and fundamental rights that, among others, includes the right to public transportation. Therefore there’s a real need of an integrated approach of community participation, FAR distribution, urban planning and transportation planning and so that urbanization, inevitable these days, takes place in a fair and harmonious way. (Author)

  8. Evaluation of burnup credit for accommodating PWR spent nuclear fuel in high-capacity cask designs

    International Nuclear Information System (INIS)

    Wagner, John C.

    2003-01-01

    This paper presents an evaluation of the amount of burnup credit needed for high-density casks to transport the current U.S. inventory of commercial spent nuclear fuel (SNF) assemblies. A prototypic 32-assembly cask and the current regulatory guidance were used as bases for this evaluation. By comparing actual pressurized-water-reactor (PWR) discharge data (i.e., fuel burnup and initial enrichment specifications for fuel assemblies discharged from U.S. PWRs) with actinide-only-based loading curves, this evaluation finds that additional negative reactivity (through either increased credit for fuel burnup or cask design/utilization modifications) is necessary to accommodate the majority of SNF assemblies in high-capacity storage and transportation casks. The impact of varying selected calculational assumptions is also investigated, and considerable improvement in effectiveness is shown with the inclusion of the principal fission products (FPs) and minor actinides and the use of a bounding best-estimate approach for isotopic validation. Given sufficient data for validation, the most significant component that would improve accuracy, and subsequently enhance the utilization of burnup credit, is the inclusion of FPs. (author)

  9. An Aqueous Redox-Flow Battery with High Capacity and Power: The TEMPTMA/MV System.

    Science.gov (United States)

    Janoschka, Tobias; Martin, Norbert; Hager, Martin D; Schubert, Ulrich S

    2016-11-07

    Redox-flow batteries (RFB) can easily store large amounts of electric energy and thereby mitigate the fluctuating output of renewable power plants. They are widely discussed as energy-storage solutions for wind and solar farms to improve the stability of the electrical grid. Most common RFB concepts are based on strongly acidic metal-salt solutions or poorly performing organics. Herein we present a battery which employs the highly soluble N,N,N-2,2,6,6-heptamethylpiperidinyl oxy-4-ammonium chloride (TEMPTMA) and the viologen derivative N,N'-dimethyl-4,4-bipyridinium dichloride (MV) in a simple and safe aqueous solution as redox-active materials. The resulting battery using these electrolyte solutions has capacities of 54 Ah L -1 , giving a total energy density of 38 Wh L -1 at a cell voltage of 1.4 V. With peak current densities of up to 200 mA cm -2 the TEMPTMA/MV system is a suitable candidate for compact high-capacity and high-power applications. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Association Between Leisure Time Physical Activity, Cardiopulmonary Fitness, Cardiovascular Risk Factors, and Cardiovascular Workload at Work in Firefighters.

    Science.gov (United States)

    Yu, Clare C W; Au, Chun T; Lee, Frank Y F; So, Raymond C H; Wong, John P S; Mak, Gary Y K; Chien, Eric P; McManus, Alison M

    2015-09-01

    Overweight, obesity, and cardiovascular disease risk factors are prevalent among firefighters in some developed countries. It is unclear whether physical activity and cardiopulmonary fitness reduce cardiovascular disease risk and the cardiovascular workload at work in firefighters. The present study investigated the relationship between leisure-time physical activity, cardiopulmonary fitness, cardiovascular disease risk factors, and cardiovascular workload at work in firefighters in Hong Kong. Male firefighters (n = 387) were randomly selected from serving firefighters in Hong Kong (n = 5,370) for the assessment of cardiovascular disease risk factors (obesity, hypertension, diabetes mellitus, dyslipidemia, smoking, known cardiovascular diseases). One-third (Target Group) were randomly selected for the assessment of off-duty leisure-time physical activity using the short version of the International Physical Activity Questionnaire. Maximal oxygen uptake was assessed, as well as cardiovascular workload using heart rate monitoring for each firefighter for four "normal" 24-hour working shifts and during real-situation simulated scenarios. Overall, 33.9% of the firefighters had at least two cardiovascular disease risk factors. In the Target Group, firefighters who had higher leisure-time physical activity had a lower resting heart rate and a lower average working heart rate, and spent a smaller proportion of time working at a moderate-intensity cardiovascular workload. Firefighters who had moderate aerobic fitness and high leisure-time physical activity had a lower peak working heart rate during the mountain rescue scenario compared with firefighters who had low leisure-time physical activities. Leisure-time physical activity conferred significant benefits during job tasks of moderate cardiovascular workload in firefighters in Hong Kong.

  11. The Impact of Sleep Restriction and Simulated Physical Firefighting Work on Acute Inflammatory Stress Responses.

    Science.gov (United States)

    Wolkow, Alexander; Ferguson, Sally A; Vincent, Grace E; Larsen, Brianna; Aisbett, Brad; Main, Luana C

    2015-01-01

    This study investigated the effect restricted sleep has on wildland firefighters' acute cytokine levels during 3 days and 2 nights of simulated physical wildfire suppression work. Firefighters completed multiple days of physical firefighting work separated by either an 8-h (Control condition; n = 18) or 4-h (Sleep restriction condition; n = 17) sleep opportunity each night. Blood samples were collected 4 times a day (i.e., 06:15, 11:30, 18:15, 21:30) from which plasma cytokine levels (IL-6, IL-8, IL-1β, TNF-α, IL-4, IL-10) were measured. The primary findings for cytokine levels revealed a fixed effect for condition that showed higher IL-8 levels among firefighters who received an 8-h sleep each night. An interaction effect demonstrated differing increases in IL-6 over successive days of work for the SR and CON conditions. Fixed effects for time indicated that IL-6 and IL-4 levels increased, while IL-1β, TNF-α and IL-8 levels decreased. There were no significant effects for IL-10 observed. Findings demonstrate increased IL-8 levels among firefighters who received an 8-h sleep when compared to those who had a restricted 4-h sleep. Firefighters' IL-6 levels increased in both conditions which may indicate that a 4-h sleep restriction duration and/or period (i.e., 2 nights) was not a significant enough stressor to affect this cytokine. Considering the immunomodulatory properties of IL-6 and IL-4 that inhibit pro-inflammatory cytokines, the rise in IL-6 and IL-4, independent of increases in IL-1β and TNF-α, could indicate a non-damaging response to the stress of simulated physical firefighting work. However, given the link between chronically elevated cytokine levels and several diseases, further research is needed to determine if firefighters' IL-8 and IL-6 levels are elevated following repeated firefighting deployments across a fire season and over multiple fire seasons.

  12. Impact of Different Personal Protective Clothing on Wildland Firefighters' Physiological Strain.

    Science.gov (United States)

    Carballo-Leyenda, Belén; Villa, José G; López-Satué, Jorge; Rodríguez-Marroyo, Jose A

    2017-01-01

    Wildfire firefighting is an extremely demanding occupation performed under hot environment. The use of personal protective clothing (PPC) is needed to protect subjects from the thermal exposure. However, the additional use of PPC may increase the wildland firefighters' physiological strain, and consequently limit their performance. The aim of this study was to analyze the effect of four different PPC on the physiological strain of wildland firefighters under moderate conditions (30°C and 30% RH). Eight active and healthy wildland firefighters performed a submaximal walking test wearing a traditional short sports gear and 4 different PPC. The materials combination (viscose, Nomex, Kevlar, P-140 and fire resistant cotton) used during the PPC manufacturing process was different. During all tests, to simulate a real scenario subjects wore a backpack pump (20 kg). Heart rate, respiratory gas exchange, gastrointestinal temperature, blood lactate concentration, perceived exertion and temperature and humidity underneath the PPC were recorded throughout tests. Additionally, parameters of heat balance were estimated. Wearing a PPC did not cause a significant increase in the subjects' physiological response. The gastrointestinal temperature increment, the relative humidity of the microclimate underneath the PPC, the sweat residue in PPC, the sweat efficiency, the dry heat exchange and the total clothing insulation were significantly affected according to the PPC fabric composition. These results suggest that the PPC composition affect the moisture management. This might be taken into account to increase the wildland firefighters' protection in real situations, when they have to work close to the flames.

  13. Impact of Different Personal Protective Clothing on Wildland Firefighters' Physiological Strain

    Directory of Open Access Journals (Sweden)

    Belén Carballo-Leyenda

    2017-08-01

    Full Text Available Wildfire firefighting is an extremely demanding occupation performed under hot environment. The use of personal protective clothing (PPC is needed to protect subjects from the thermal exposure. However, the additional use of PPC may increase the wildland firefighters' physiological strain, and consequently limit their performance. The aim of this study was to analyze the effect of four different PPC on the physiological strain of wildland firefighters under moderate conditions (30°C and 30% RH. Eight active and healthy wildland firefighters performed a submaximal walking test wearing a traditional short sports gear and 4 different PPC. The materials combination (viscose, Nomex, Kevlar, P-140 and fire resistant cotton used during the PPC manufacturing process was different. During all tests, to simulate a real scenario subjects wore a backpack pump (20 kg. Heart rate, respiratory gas exchange, gastrointestinal temperature, blood lactate concentration, perceived exertion and temperature and humidity underneath the PPC were recorded throughout tests. Additionally, parameters of heat balance were estimated. Wearing a PPC did not cause a significant increase in the subjects' physiological response. The gastrointestinal temperature increment, the relative humidity of the microclimate underneath the PPC, the sweat residue in PPC, the sweat efficiency, the dry heat exchange and the total clothing insulation were significantly affected according to the PPC fabric composition. These results suggest that the PPC composition affect the moisture management. This might be taken into account to increase the wildland firefighters' protection in real situations, when they have to work close to the flames.

  14. Aviation-Related Wildland Firefighter Fatalities--United States, 2000-2013.

    Science.gov (United States)

    Butler, Corey R; O'Connor, Mary B; Lincoln, Jennifer M

    2015-07-31

    Airplanes and helicopters are integral to the management and suppression of wildfires, often operating in high-risk, low-altitude environments. To update data on aviation-related wildland firefighting fatalities, identify risk factors, and make recommendations for improved safety, CDC's National Institute for Occupational Safety and Health (NIOSH) analyzed reports from multiple data sources for the period 2000-2013. Among 298 wildland firefighter fatalities identified during 2000-2013, 78 (26.2%) were aviation-related occupational fatalities that occurred during 41 separate events involving 42 aircraft. Aircraft crashes accounted for 38 events. Pilots, copilots, and flight engineers represented 53 (68%) of the aviation-related fatalities. The leading causes of fatal aircraft crashes were engine, structure, or component failure (24%); pilot loss of control (24%); failure to maintain clearance from terrain, water, or objects (20%); and hazardous weather (15%). To reduce fatalities from aviation-related wildland firefighting activities, stringent safety guidelines need to be followed during all phases of firefighting, including training exercises. Crew resource management techniques, which use all available resources, information, equipment, and personnel to achieve safe and efficient flight operations, can be applied to firefighting operations.

  15. Women Firefighters and Workplace Harassment: Associated Suicidality and Mental Health Sequelae.

    Science.gov (United States)

    Hom, Melanie A; Stanley, Ian H; Spencer-Thomas, Sally; Joiner, Thomas E

    2017-12-01

    This cross-sectional study investigated the association between harassment, career suicidality, and psychiatric symptoms among women firefighters. Women firefighters (n = 290) completed self-report measures of experiences with harassment on the job, career suicidality, and various psychiatric symptoms. Logistic regression analyses and one-way analyses of variance were used to address study aims. Of the sample, 21.7% reported having experienced sexual harassment and 20.3% reported having been threatened or harassed in another way on their firefighting job. Sexual harassment and other threats/harassment on the job were both significantly associated with a greater likelihood of reporting career suicidal ideation, as well as reporting more severe psychiatric symptoms. Harassment and threats experienced on the job may be associated with increased suicide risk and more severe psychiatric symptoms among women firefighters. Efforts are needed to reduce the occurrence of harassment and threats within the fire service and provide support for women firefighters who have been harassed or threatened.

  16. Dietary Preferences and Nutritional Information Needs Among Career Firefighters in the United States.

    Science.gov (United States)

    Yang, Justin; Farioli, Andrea; Korre, Maria; Kales, Stefanos N

    2015-07-01

    Considerable cardiovascular disease and cancer risk among firefighters are attributable to excess adiposity. Robust evidence confirms strong relationships between dietary patterns and the risk of chronic disease. Dietary modification is more likely to be effective when the strategy is appealing and addresses knowledge gaps. To assess career firefighters' diet practices and information needs, compare the relative appeal of proposed diet plans, and examine how these vary in association with body composition. Cross-sectional, online survey distributed to members of the International Association of Fire Fighters. Most firefighters do not currently follow any specific dietary plan (71%) and feel that they receive insufficient nutrition information (68%), but most are interested in learning more about healthy eating (75%). When presented with written descriptions of diets without names or labels and asked to rank them in order of preference, firefighters most often rated the Mediterranean diet as their favorite and gave it a more favorable distribution of relative rankings (PPaleo, Atkins, Therapeutic Lifestyle Changes, and Esselsteyn Engine 2 (low-fat, strictly plant-based) diets. Obese respondents reported more limited nutritional knowledge (Pdiet; however, 75% want to learn more about healthy eating. Among popular dietary choices, firefighters were most receptive to a Mediterranean diet and least receptive to a strictly plant-based diet.

  17. The effectiveness of Narrative Exposure Therapy with traumatised firefighters in Saudi Arabia: a randomized controlled study.

    Science.gov (United States)

    Alghamdi, Mohammed; Hunt, Nigel; Thomas, Shirley

    2015-03-01

    Firefighters are exposed to many traumatic events. The psychological costs of this exposure increase the risk of Post-Traumatic Stress disorder (PTSD), depression and anxiety. This study examined the effectiveness of Narrative Exposure Therapy (NET) as a short-term treatment for reducing PTSD symptoms among Saudi firefighters. A randomized waiting-list control study was conducted with 34 traumatized firefighters were randomly allocated to NET or Waiting-list Control (WLC). The NET group received four therapy sessions of 60-90 min over a three-week period; those in the WLC condition received the same sessions after a three-week waiting period. Participants in both groups were assessed at baseline, immediately post-intervention and at 3 and 6 month follow ups. NET led to significant reductions in PTSD symptoms, anxiety and depression compared with WLC. After the WLC group received treatment, it showed the same improvements as the NET group. This occurred immediately post-treatment in both groups, but was not sustained at 3 and 6 month follow ups. Coping strategies and social support led to significant changes only in follow up times. NET was effective in reducing PTSD symptoms in traumatised Saudi firefighters. This finding could be helpful in the management of PTSD among people who work as first responders such as firefighters, police officers and emergency medical personal, as well as security officers. Copyright © 2015. Published by Elsevier Ltd.

  18. Fatigue risk management by volunteer fire-fighters: Use of informal strategies to augment formal policy.

    Science.gov (United States)

    Dawson, Drew; Mayger, Katherine; Thomas, Matthew J W; Thompson, Kirrilly

    2015-11-01

    An increasing number and intensity of catastrophic fire events in Australia has led to increasing demands on a mainly volunteer fire-fighting workforce. Despite the increasing likelihood of fatigue in the emergency services environment, there is not yet a systematic, unified approach to fatigue management in fire agencies across Australia. Accordingly, the aim of this study was to identify informal strategies used in volunteer fire-fighting and examine how these strategies are transmitted across the workforce. Thirty experienced Australian volunteer fire-fighters were interviewed in August 2010. The study identified informal fatigue-management behaviours at the individual, team and brigade level that have evolved in fire-fighting environments and are regularly implemented. However, their purpose was not explicitly recognized as such. This apparent paradox - that fatigue proofing behaviours exist but that they are not openly understood as such - may well resolve a potential conflict between a culture of indefatigability in the emergency services sector and the frequent need to operate safely while fatigued. However, formal controls require fire-fighters and their organisations to acknowledge and accept their vulnerability. This suggests two important areas in which to improve formal fatigue risk management in the emergency services sector: (1) identifying and formalising tacit or informal fatigue coping strategies as legitimate elements of the fatigue risk management system; and (2) developing culturally appropriate techniques for systematically communicating fatigue levels to self and others. Copyright © 2015 Elsevier Ltd. All rights reserved.

  19. Outbreak of cryptosporidiosis associated with a firefighting response - Indiana and Michigan, June 2011.

    Science.gov (United States)

    2012-03-09

    On June 20, 2011, the Indiana Department of Homeland Security notified the Indiana State Department of Health (ISDH) of an Indiana fire station that reported gastrointestinal illness among a substantial percentage of their workers, causing missed workdays and one hospitalization as a result of cryptosporidiosis. All ill firefighters had responded to a barn fire in Michigan, 15 miles from the Michigan-Indiana border on June 6; responding firefighters from Michigan also had become ill. ISDH immediately contacted the Michigan Department of Community Health (MDCH) concerning this outbreak. The investigation was led by MDCH in partnership with ISDH and the Michigan local health department (LHD). Among 34 firefighters who responded to the fire, 33 were interviewed, and 20 (61%) reported gastrointestinal illness ≤12 days after the fire. Cryptosporidium parvum was identified in human stool specimens, calf fecal samples, and a swimming pond. Based on these findings, the following public health recommendations were issued: 1) discontinue swimming in the pond, 2) practice thorough hygiene to reduce fecal contamination and fecal-oral exposures, and 3) decontaminate firefighting equipment properly. No additional primary or secondary cases associated with this exposure have been reported. The findings highlight a novel work-related disease exposure for firefighters and the need for public education regarding cryptosporidiosis prevention.

  20. 33 CFR 155.4045 - Required agreements or contracts with the salvage and marine firefighting resource providers.

    Science.gov (United States)

    2010-07-01

    ... with the salvage and marine firefighting resource providers. 155.4045 Section 155.4045 Navigation and... agreements or contracts with the salvage and marine firefighting resource providers. (a) You may only list resource providers in your plan that have been arranged by contract or other approved means. (b) You must...

  1. Adding sleep restriction to the equation: impact on wildland firefighters' work performance and physiology in hot conditions.

    Science.gov (United States)

    Vincent, Grace E; Ferguson, Sally; Larsen, Brianna; Ridgers, Nicola D; Snow, Rod; Aisbett, Brad

    2018-04-06

    To examine the effects of sleep restriction on firefighters' physical task performance, physical activity, and physiological and perceived exertion during simulated hot wildfire conditions. 31 firefighters were randomly allocated to either the hot (n = 18, HOT; 33 °C, 8-h sleep opportunity) or hot and sleep restricted (n = 13, HOT + SR; 33 °C, 4-h sleep opportunity) condition. Intermittent, self-paced work circuits of six firefighting tasks were performed for 3 days. Firefighters self-reported ratings of perceived exertion. Heart rate, core temperature, and physical activity were measured continuously. Fluids were consumed ad libitum, and all food and fluids consumed were recorded. Urine volume and urine specific gravity (USG) were analysed and sleep was assessed using polysomnography (PSG). There were no differences between the HOT and HOT + SR groups in firefighters' physical task performance, heart rate, core temperature, USG, or fluid intake. Ratings of perceived exertion were higher (p HOT + SR group for two of the six firefighting tasks. The HOT group spent approximately 7 min more undertaking moderate physical activity throughout the 2-h work circuits compared to the HOT + SR group. Two nights of sleep restriction did not influence firefighters' physical task performance or physiological responses during 3 days of simulated wildfire suppression. Further research is needed to explore firefighters' pacing strategies during real wildfire suppression.

  2. Occupational stress and strain in relation to personal protective equipment of Japanese firefighters assessed by a questionnaire.

    Science.gov (United States)

    Son, Su-Young; Lee, Joo-Young; Tochihara, Yutaka

    2013-01-01

    The purpose of the present study was to elucidate differences in actual work environments, mobility and satisfaction between firefighters wearing aluminized and non-aluminized personal protective equipment (PPE), and to suggest a proper standard test method for Japanese firefighters' PPE. A survey from two cities in Japan (City A: aluminized PPE; City B: non aluminized PPE) was undertaken. A total of 525 firefighters from City A and 757 from City B participated. Firefighters spent 22.5 min (City A) and 27.3 min (City B) on average firefighting with the full set of PPE in one incident, but the heat strain experienced among firefighters from City A was twice that of firefighters from City B (57.5% and 28.4%). Firefighters spent 65.9 min on one incident and 24.2 min for suppression of fire with the full set of PPE on average. The toughest task that caused physical strain in City A was 'stair climbing' and in City B was 'drawing up a hose filled with water'. The most restricted body region due to PPE was the knee for both groups. Evaluations revealed that the aluminized fire jacket had worse ventilation and mobility than the non-aluminized, while the non-aluminized one received with more unfavorable evaluations for water resistance and maintainability.

  3. Personal PM2.5 exposure among wildland firefighters working at prescribed forest burns in southeastern United States

    Science.gov (United States)

    O Adetona; K Dunn; Gary Achtemeier; A Stock; L Naeher

    2011-01-01

    Wildland firefighters are primarily responsible forwildfire suppression in wildlands, including forests, grasslands, and brush, but also engage in prescribed burning. Prescribed burns, as opposed to wildfires, are intentionally set by firefighters and are used as a land management tool for improving forage value of the forests, and reducing wildfire hazard and...

  4. The Impact of Heat Exposure and Sleep Restriction on Firefighters' Work Performance and Physiology during Simulated Wildfire Suppression.

    Science.gov (United States)

    Vincent, Grace E; Aisbett, Brad; Larsen, Brianna; Ridgers, Nicola D; Snow, Rod; Ferguson, Sally A

    2017-02-12

    This study was designed to examine the effects of ambient heat on firefighters' physical task performance, and physiological and perceptual responses when sleep restricted during simulated wildfire conditions. Thirty firefighters were randomly allocated to the sleep restricted ( n = 17, SR; 19 °C, 4-h sleep opportunity) or hot and sleep restricted ( n = 13, HOT + SR; 33 °C, 4-h sleep opportunity) condition. Firefighters performed two days of simulated, intermittent, self-paced work circuits comprising six firefighting tasks. Heart rate, and core temperature were measured continuously. After each task, firefighters reported their rating of perceived exertion and thermal sensation. Effort sensation was also reported after each work circuit. Fluids were consumed ad libitum. Urine volume and urine specific gravity were analysed. Sleep was monitored using polysomnography. There were no differences between the SR and HOT + SR groups in firefighters' physiological responses, hydration status, ratings of perceived exertion, motivation, and four of the six firefighting tasks (charged hose advance, rake, hose rolling, static hose hold). Black out hose and lateral repositioning were adversely affected in the HOT + SR group. Working in hot conditions did not appear to consistently impair firefighters work performance, physiology, and perceptual responses. Future research should determine whether such findings remain true when individual tasks are performed over longer durations.

  5. Copper sulfide microspheres wrapped with reduced graphene oxide for high-capacity lithium-ion storage

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yiyong; Li, Kun; Wang, Yunhui; Zeng, Jing; Ji, Panying; Zhao, Jinbao, E-mail: jbzhao@xmu.edu.cn

    2016-11-15

    Highlights: • We prepare the nanocomposites of Cu{sub x}S microspheres wrapped with rGO. • As-prepared Cu{sub x}S/rGO can effectively accommodate large volume changes. • As-prepared Cu{sub x}S/rGO supply a 2D conductive network. • As-prepared Cu{sub x}S/rGO trap the polysulfides generated during the discharge–charge. • The Cu{sub x}S/rGO has high capacity, cycle stability and excellent rate capability. - Abstract: In this study, a facile two-step approach was developed to prepare the nanocomposites (Cu{sub x}S/rGO) of copper sulfide (Cu{sub x}S) microspheres wrapped with reduced graphene oxide (rGO). The morphology and structure of Cu{sub x}S/rGO materials were researched by using SEM, XRD and laser Raman spectroscopy. As-prepared Cu{sub x}S/rGO nanocomposites, as an active anode material in LIBs, showed distinctly improved electrochemical characteristics, superior cycling stability and high rate capability. Due to the synergistic effect between the Cu{sub x}S microspheres and the rGO nanosheets, as-prepared Cu{sub x}S/rGO nanocomposites could effectively alleviate large volume changes, provide a 2D conductive network and trap the diffusion of polysulfides during the discharge–charge processes, therefore, the Cu{sub x}S/rGO nanocomposites showed excellent electrochemical characteristics.

  6. High-capacity thermo-responsive magnetic molecularly imprinted polymers for selective extraction of curcuminoids.

    Science.gov (United States)

    You, Qingping; Zhang, Yuping; Zhang, Qingwen; Guo, Junfang; Huang, Weihua; Shi, Shuyun; Chen, Xiaoqin

    2014-08-08

    Thermo-responsive magnetic molecularly imprinted polymers (TMMIPs) for selective recognition of curcuminoids with high capacity and selectivity have firstly been developed. The resulting TMMIPs were characterized by TEM, FT-IR, TGA, VSM and UV, which indicated that TMMIPs showed thermo-responsiveness [lower critical solution temperature (LCST) at 33.71°C] and rapid magnetic separation (5s). The polymerization, adsorption and release conditions were optimized in detail to obtain the highest binding capacity, selectivity and release ratio. We found that the adopted thermo-responsive monomer [N-isopropylacrylamide (NIPAm)] could be considered not only as inert polymer backbone for thermo-responsiveness but also as functional co-monomers combination with basic monomer (4-VP) for more specific binding sites when ethanol was added in binding solution. The maximum adsorption capacity with highest selectivity of curcumin was 440.3μg/g (1.93 times that on MMIPs with no thermosensitivity) at 45°C (above LCST) in 20% (v/v) ethanol solution on shrunk TMMIPs, and the maximum release proportion was about 98% at 20°C (below LCST) in methanol-acetic acid (9/1, v/v) solution on swelled TMMIPs. The adsorption process between curcumin and TMMIPs followed Langumuir adsorption isotherm and pseudo-first-order reaction kinetics. The prepared TMMIPs also showed high reproducibility (RSD<6% for batch-to-batch evaluation) and stability (only 7% decrease after five cycles). Subsequently, the TMMIPs were successfully applied for selective extraction of curcuminoids from complex natural product, Curcuma longa. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Groundwater-Surface water interaction in agricultural watershed that encompasses dense network of High Capacity wells

    Science.gov (United States)

    Talib, A.; Desai, A. R.

    2017-12-01

    The Central Sands region of Wisconsin is characterized by productive trout streams, lakes, farmland and forest. However, stream channelization, past wetland drainage, and ground water withdrawals have disrupted the hydrology of this Central Sands region. Climatically driven conditions in last decade (2000-2008) alone are unable to account for the severely depressed water levels. Increased interception and evapotranspiration from afforested areas in central sand Wisconsin may also be culprit for reduced water recharge. Hence, there is need to study the cumulative effects of changing precipitation patterns, groundwater withdrawals, and forest evapotranspiration to improve projections of the future of lake levels and water availability in this region. Here, the SWAT-MODFLOW coupled model approach was applied at large spatio-temporal scale. The coupled model fully integrates a watershed model (SWAT) with a groundwater flow model (MODFLOW). Surface water and ground water flows were simulated integratively at daily time step to estimate the groundwater discharge to the stream network in Central Sands that encompasses high capacity wells. The model was calibrated (2010-2013) and validated (2014-2017) based on streamflow, groundwater extraction, and water table elevation. As the long-term trends in some of the primary drivers is presently ambiguous in Central Sands under future climate, as is the case for total precipitation or timing of precipitation, we relied on a sensitivity student to quantitatively access how primary and secondary drivers may influence future net groundwater recharge. We demonstrate how such an approach could then be coupled with decision-making models to evaluate the effectiveness of groundwater withdrawal policies under a changing climate.

  8. A Low Cost, High Capacity Regenerable Sorbent for Pre-combustion CO{sub 2} Capture

    Energy Technology Data Exchange (ETDEWEB)

    Alptekin, Gokhan

    2012-09-30

    The overall objective of the proposed research is to develop a low cost, high capacity CO{sub 2} sorbent and demonstrate its technical and economic viability for pre-combustion CO{sub 2} capture. The specific objectives supporting our research plan were to optimize the chemical structure and physical properties of the sorbent, scale-up its production using high throughput manufacturing equipment and bulk raw materials and then evaluate its performance, first in bench-scale experiments and then in slipstream tests using actual coal-derived synthesis gas. One of the objectives of the laboratory-scale evaluations was to demonstrate the life and durability of the sorbent for over 10,000 cycles and to assess the impact of contaminants (such as sulfur) on its performance. In the field tests, our objective was to demonstrate the operation of the sorbent using actual coal-derived synthesis gas streams generated by air-blown and oxygen-blown commercial and pilot-scale coal gasifiers (the CO{sub 2} partial pressure in these gas streams is significantly different, which directly impacts the operating conditions hence the performance of the sorbent). To support the field demonstration work, TDA collaborated with Phillips 66 and Southern Company to carry out two separate field tests using actual coal-derived synthesis gas at the Wabash River IGCC Power Plant in Terre Haute, IN and the National Carbon Capture Center (NCCC) in Wilsonville, AL. In collaboration with the University of California, Irvine (UCI), a detailed engineering and economic analysis for the new CO{sub 2} capture system was also proposed to be carried out using Aspen PlusTM simulation software, and estimate its effect on the plant efficiency.

  9. MX 8: the next generation high capacity system for the transport of fresh MOX fuel

    International Nuclear Information System (INIS)

    Potelle, F.; Issard, H.

    1998-01-01

    The choice of reprocessing policy was made a long time ago in France, leading to the development of an advanced Pu recycling industry. In 1987, Saint Laurent was the first French reactor to be loaded with fresh MOX fuel. Transnucleaire, then in charge of transport packaging development, created the FS 69 concept, derived from the classical RCC concept for the transport of UO 2 fresh fuel. On the other hand, Cogema, as the main actor in the field of fuel cycle and thus in transport matters, developed the associated security truck and security caisson in order to provide the transport system with the acceptable Physical Protection devices required by French Authorities. As a whole, the security truck and the FS 69 have now been used for more than ten years with a remarkable level of efficiency and safety. Indeed, more than 600 fresh MOX fuel elements have been delivered, without any incident, both regarding safety or fuel integrity requirements. But, as a matter of fact, the replacement of FS 69 transport system is now scheduled for several reasons. First of all, the burnups achieved with UO 2 fuel progressed together with its enrichment within the last ten years, and the MOX 'equivalence' also implies that its Pu content be increased to enhance its reactor performances: from 5.25 % of Pu content today, the MOX fuel will reach 7% tomorrow, and almost 10% the day after tomorrow. Lastly, the reprocessing/recycling policy has been confirmed and amplified, leading to an increasing number of 'moxified' reactors. As a consequence, the French utility (EDF), the fuel designer (Fragema, the joint venture between Framatome and Cogema), the fuel manufacturer (Cogema), and the transporter (Transnucleaire) joined in a specific working group devoted to the development of the MX 8, the next generation high capacity system for the land transport of MOX fuel. (authors)

  10. Binders and Hosts for High-Capacity Lithium-ion Battery Anodes

    Science.gov (United States)

    Dufficy, Martin Kyle

    Lithium-ion batteries (LIBs) are universal electrochemical energy storage devices that have revolutionized our mobile society. Nonetheless, societal and technological advances drive consumer demand for LIBs with enhanced electrochemical performance, such as higher charge capacity and longer life, compared to conventional LIBs. One method to enhance LIB performance is to replace graphite, the industry standard anode since commercialization of LIBs in 1991, with high-charge capacity materials. Implementing high-capacity anode materials such as tin, silicon, and manganese vanadates, to LIBs presents challenges; Li-insertion is destructive to anode framework, and increasing capacity increases structural strains that pulverize anode materials and results in a short-cycle life. This thesis reports on various methods to extended the cycle life of high-capacity materials. Most of the work is conducted on nano-sized anode materials to reduce Li and electron transport pathway length (facilitating charge-transfer) and reduce strains from volume expansions (preserving anode structure). The first method involves encapsulating tin particles into a graphene-containing carbon nanofiber (CNF) matrix. The composite-CNF matrix houses tin particles to assume strains from tin-volume expansions and produces favorable surface-electrolyte chemistries for stable charge-discharge cycling. Before tin addition, graphene-containing CNFs are produced and assessed as anode materials for LIBs. Graphene addition to CNFs improves electronic and mechanical properties of CNFs. Furthermore, the 2-D nature of graphene provides Li-binding sites to enhance composite-CNF both first-cycle and high-rate capacities > 150% when compared to CNFs in the absence of graphene. With addition of Sn, we vary loadings and thermal production temperature to elucidate structure-composition relationships of tin and graphene-containing CNF electrodes that lead to increased capacity retention. Of note, electrodes containing

  11. Firefighters and on-duty deaths from coronary heart disease: a case control study

    Directory of Open Access Journals (Sweden)

    Soteriades Elpidoforos S

    2003-11-01

    Full Text Available Abstract Background Coronary heart disease (CHD is responsible for 45% of on-duty deaths among United States firefighters. We sought to identify occupational and personal risk factors associated with on-duty CHD death. Methods We performed a case-control study, selecting 52 male firefighters whose CHD deaths were investigated by the National Institute for Occupational Safety and Health. We selected two control populations: 51 male firefighters who died of on-duty trauma; and 310 male firefighters examined in 1996/1997, whose vital status and continued professional activity were re-documented in 1998. Results The circadian pattern of CHD deaths was associated with emergency response calls: 77% of CHD deaths and 61% of emergency dispatches occurred between noon and midnight. Compared to non-emergency duties, fire suppression (OR = 64.1, 95% CI 7.4–556; training (OR = 7.6, 95% CI 1.8–31.3 and alarm response (OR = 5.6, 95% CI 1.1–28.8 carried significantly higher relative risks of CHD death. Compared to the active firefighters, the CHD victims had a significantly higher prevalence of cardiovascular risk factors in multivariate regression models: age ≥ 45 years (OR 6.5, 95% CI 2.6–15.9, current smoking (OR 7.0, 95% CI 2.8–17.4, hypertension (OR 4.7, 95% CI 2.0–11.1, and a prior diagnosis of arterial-occlusive disease (OR 15.6, 95% CI 3.5–68.6. Conclusions Our findings strongly support that most on-duty CHD fatalities are work-precipitated and occur in firefighters with underlying CHD. Improved fitness promotion, medical screening and medical management could prevent many of these premature deaths.

  12. An Internet-based tailored hearing protection intervention for firefighters: development process and users' feedback.

    Science.gov (United States)

    Hong, OiSaeng; Eakin, Brenda L; Chin, Dal Lae; Feld, Jamie; Vogel, Stephen

    2013-07-01

    Noise-induced hearing loss is a significant occupational injury for firefighters exposed to intermittent noise on the job. It is important to educate firefighters about using hearing protection devices whenever they are exposed to loud noise. Computer technology is a relatively new health education approach and can be useful for tailoring specific aspects of behavioral change training. The purpose of this study is to present the development process of an Internet-based tailored intervention program and to assess its efficacy. The intervention programs were implemented for 372 firefighters (mean age = 44 years, Caucasian = 82%, male = 95%) in three states (California, Illinois, and Indiana). The efficacy was assessed from firefighters' feedback through an Internet-based survey. A multimedia Internet-based training program was developed through (a) determining program content and writing scripts, (b) developing decision-making algorithms for tailoring, (c) graphic design and audio and video productions, (d) creating computer software and a database, and (e) postproduction quality control and pilot testing. Participant feedback regarding the training has been very positive. Participants reported that they liked completing the training via computer (83%) and also that the Internet-based training program was well organized (97%), easy to use (97%), and effective (98%) and held their interest (79%). Almost all (95%) would recommend this Internet training program to other firefighters. Interactive multimedia computer technology using the Internet was a feasible mode of delivery for a hearing protection intervention among firefighters. Participants' favorable feedback strongly supports the continued utilization of this approach for designing and developing interventions to promote healthy behaviors.

  13. Exploratory breath analyses for assessing toxic dermal exposures of firefighters during suppression of structural burns.

    Science.gov (United States)

    Pleil, Joachim D; Stiegel, Matthew A; Fent, Kenneth W

    2014-09-01

    Firefighters wear fireproof clothing and self-contained breathing apparatus (SCBA) during rescue and fire suppression activities to protect against acute effects from heat and toxic chemicals. Fire services are also concerned about long-term health outcomes from chemical exposures over a working lifetime, in particular about low-level exposures that might serve as initiating events for adverse outcome pathways (AOP) leading to cancer. As part of a larger US National Institute for Occupational Safety and Health (NIOSH) study of dermal exposure protection from safety gear used by the City of Chicago firefighters, we collected pre- and post-fire fighting breath samples and analyzed for single-ring and polycyclic aromatic hydrocarbons as bioindicators of occupational exposure to gas-phase toxicants. Under the assumption that SCBA protects completely against inhalation exposures, any changes in the exhaled profile of combustion products were attributed to dermal exposures from gas and particle penetration through the protective clothing. Two separate rounds of firefighting activity were performed each with 15 firefighters per round. Exhaled breath samples were collected onto adsorbent tubes and analyzed with gas-chromatography-mass spectrometry (GC-MS) with a targeted approach using selective ion monitoring. We found that single ring aromatics and some PAHs were statistically elevated in post-firefighting samples of some individuals, suggesting that fire protective gear may allow for dermal exposures to airborne contaminants. However, in comparison to a previous occupational study of Air Force maintenance personnel where similar compounds were measured, these exposures are much lower suggesting that firefighters' gear is very effective. This study suggests that exhaled breath sampling and analysis for specific targeted compounds is a suitable method for assessing systemic dermal exposure in a simple and non-invasive manner.

  14. Body mass index and body composition among rescue firefighters personnel in Selangor, Malaysia

    Science.gov (United States)

    Rahimi, Nor Atiqah; Sedek, Razalee; Teh, Arnida Hani

    2016-11-01

    Obesity is a major public health problem in general population and there is no exception for firefighters. This disorder is definitely a burden for firefighters as they needed to be physically fit in order to work in dangerous situation and extinguishing fires. The purposes of this study were to determine physical characteristics and body composition among Malaysian Firefighters (MF) and to explore their association. This cross-sectional study involved 330 rescue firefighters aged between 20-50 years old from nine different districts in Selangor conducted between August and November 2015. Anthropometric measurements included height, weight and waist circumference (WC). Body composition was measured using bioelectrical impedance. The mean height, weight, body mass index (BMI), WC and body fat percentage were 169.4±5.3 cm, 74.5±12.2 kg, 25.9±3.82 kg/m2, 90.7±48.3 cm and 25.8±6.2 % respectively. The results also showed that 0.6% of them were underweight, 41.5% were normal, 44.8% were overweight and 13% were obese. The percentage of 34.8% firefighters with WC values of more than 90 cm means that they were at greater risk to have cardiovascular and diabetes disease. Body composition analysis showed that 75.5% of the subjects have high body fat level, 19.7% subjects were in healthy range but only 4.8% were considered as lean subjects. BMI was highly correlated with weight (r=0.917, p<0.01), WC (r=0.858, p<0.01) and body fat percentage (r=0.757, <0.01). Body fat percentage also showed to have a high correlation with BMI (r=0.757, p<0.01) and WC (r=0.693, p<0.01). Furthermore, overweight and obesity were found to be more prevalent among firefighters personnel of older age, married, less educated and have longer duration of services. It can be concluded that more than half of the firefighter personnel were either overweight or obese and 35% of them were at greater risk of having non-communicable diseases. This study provides useful information and serves as a source of

  15. Impact of work pressure, work stress and work-family conflict on firefighter burnout.

    Science.gov (United States)

    Smith, Todd D; DeJoy, David M; Dyal, Mari-Amanda Aimee; Huang, Gaojian

    2017-10-25

    Little research has explored burnout and its causes in the American fire service. Data were collected from career firefighters in the southeastern United States (n = 208) to explore these relationships. A hierarchical regression model was tested to examine predictors of burnout including sociodemographic characteristics (model 1), work pressure (model 2), work stress and work-family conflict (model 3) and interaction terms (model 4). The main findings suggest that perceived work stress and work-family conflict emerged as the significant predictors of burnout (both p < .001). Interventions and programs aimed at these predictors could potentially curtail burnout among firefighters.

  16. Work Functioning Among Firefighters: A Comparison Between Self-Reported Limitations and Functional Task Performance.

    Science.gov (United States)

    MacDermid, Joy C; Tang, Kenneth; Sinden, Kathryn E; D'Amico, Robert

    2018-05-25

    Purpose Performance-based and disease indicators have been widely studied in firefighters; self-reported work role limitations have not. The aim of this study was to describe the distributions and correlations of a generic self-reported Work Limitations Questionnaire (WLQ-26) and firefighting-specific task performance-based tests. Methods Active firefighters from the City of Hamilton Fire Services (n = 293) were recruited. Participants completed the WLQ-26 to quantify on-the-job difficulties over five work domains: work scheduling (4 items), output demands (7 items), physical demands (8 items), mental demands (4 items), and social demands (3 items). A subset of participants (n = 149) were also assessed on hose drag and stair climb with a high-rise pack performance-based tests. Descriptive statistics and correlations were used to compare item/subscale performance; and to describe the inter-relationships between tests. Results The mean WLQ-26 item scores (/5) ranged from 4.1 to 4.4 (median = 5 for all items); most firefighters (54.5-80.5%) selected "difficult none of the time" response option on all items. A substantial ceiling effect was observed across all five WLQ-26 subscales as 44.0-55.6% were in the highest category. Subscale means ranged from 61.8 (social demands) to 78.7 (output demands and physical demands). Internal consistency exceeded 0.90 on all subscales. For the hose drag task, the mean time-to-completion was 48.0 s (SD = 14.5; range 20.4-95.0). For the stair climb task, the mean time-to-completion was 76.7 s (SD = 37.2; range 21.0-218.0). There were no significant correlations between self-report work limitations and performance of firefighting tasks. Conclusions The WLQ-26 measured five domains, but had ceiling effects in firefighters. Performance-based testing showed wider score range, lacked ceiling effects and did not correlate to the WLQ-26. A firefighter-specific, self-report role functioning scale may be needed to identify

  17. Improving Reliability of a fire-fighting pump set with Axiomatic Design

    Directory of Open Access Journals (Sweden)

    Arcidiacono Gabriele

    2017-01-01

    Full Text Available This paper introduces a case study featuring Axiomatic Design and Multi-Level Hierarchical model (MLH applied to redesign a fire-fighting pump set. In particular, two different design concepts are presented to be applied to the supporting frame of the system to limit a vibration problem that can arise during potential malfunctioning of the fire-fighting pump. The selection of the best design has been carried out through reliability evaluation process and through the cost of failure based on the MLH model.

  18. A WSN-based tool for urban and industrial fire-fighting.

    Science.gov (United States)

    De San Bernabe Clemente, Alberto; Martínez-de Dios, José Ramiro; Ollero Baturone, Aníbal

    2012-11-06

    This paper describes a WSN tool to increase safety in urban and industrial fire-fighting activities. Unlike most approaches, we assume that there is no preexisting WSN in the building, which involves interesting advantages but imposes some constraints. The system integrates the following functionalities: fire monitoring, firefighter monitoring and dynamic escape path guiding. It also includes a robust localization method that employs RSSI-range models dynamically trained to cope with the peculiarities of the environment. The training and application stages of the method are applied simultaneously, resulting in significant adaptability. Besides simulations and laboratory tests, a prototype of the proposed system has been validated in close-to-operational conditions.

  19. Preparation of surface modified zinc oxide nanoparticle with high capacity dye removal ability

    International Nuclear Information System (INIS)

    Mahmoodi, Niyaz Mohammad; Najafi, Farhood

    2012-01-01

    Highlights: ► Amine-functionalized zinc oxide nanoparticle (AFZON) was synthesized. ► Isotherm and kinetics data followed Langmuir isotherm and pseudo-second order kinetic model, respectively. ► Q 0 of ZON for AB25, DR23 and DR31 was 20, 12 and 15 mg/g, respectively. ► Q 0 of AFZON for AB25, DR23 and DR31 was 1250, 1000 and 1429 mg/g, respectively. ► AFZON was regenerated at pH 12. -- Abstract: In this paper, the surface modification of zinc oxide nanoparticle (ZON) by amine functionalization was studied to prepare high capacity adsorbent. Dye removal ability of amine-functionalized zinc oxide nanoparticle (AFZON) and zinc oxide nanoparticle (ZON) was also investigated. The physical characteristics of AFZON were studied using Fourier transform infrared (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). Acid Blue 25 (AB25), Direct Red 23 (DR23) and Direct Red 31 (DR31) were used as model compounds. The effect of operational parameters such as dye concentration, adsorbent dosage, pH and salt on dye removal was evaluated. The isotherm and kinetic of dye adsorption were studied. The maximum dye adsorption capacity (Q 0 ) was 20 mg/g AB25, 12 mg/g DR23 and 15 mg/g DR31 for ZON and 1250 mg/g AB25, 1000 mg/g DR23 and 1429 mg/g DR31 for AFZON. It was found that dye adsorption followed Langmuir isotherm. Adsorption kinetic of dyes was found to conform to pseudo-second order kinetics. Dye desorption tests (adsorbent regeneration) showed that the maximum dye release of 90% AB25, 86% for DR23 and 90% for DR31 were achieved in aqueous solution at pH 12. Based on the data of the present investigation, it can be concluded that the AFZON being an adsorbent with high dye adsorption capacity might be a suitable alternative to remove dyes from colored aqueous solutions.

  20. Technology Assessment of High Capacity Data Storage Systems: Can We Avoid a Data Survivability Crisis?

    Science.gov (United States)

    Halem, M.; Shaffer, F.; Palm, N.; Salmon, E.; Raghavan, S.; Kempster, L.

    1998-01-01

    This technology assessment of long-term high capacity data storage systems identifies an emerging crisis of severe proportions related to preserving important historical data in science, healthcare, manufacturing, finance and other fields. For the last 50 years, the information revolution, which has engulfed all major institutions of modem society, centered itself on data-their collection, storage, retrieval, transmission, analysis and presentation. The transformation of long term historical data records into information concepts, according to Drucker, is the next stage in this revolution towards building the new information based scientific and business foundations. For this to occur, data survivability, reliability and evolvability of long term storage media and systems pose formidable technological challenges. Unlike the Y2K problem, where the clock is ticking and a crisis is set to go off at a specific time, large capacity data storage repositories face a crisis similar to the social security system in that the seriousness of the problem emerges after a decade or two. The essence of the storage crisis is as follows: since it could take a decade to migrate a peta-byte of data to a new media for preservation, and the life expectancy of the storage media itself is only a decade, then it may not be possible to complete the transfer before an irrecoverable data loss occurs. Over the last two decades, a number of anecdotal crises have occurred where vital scientific and business data were lost or would have been lost if not for major expenditures of resources and funds to save this data, much like what is happening today to solve the Y2K problem. A pr-ime example was the joint NASA/NSF/NOAA effort to rescue eight years worth of TOVS/AVHRR data from an obsolete system, which otherwise would have not resulted in the valuable 20-year long satellite record of global warming. Current storage systems solutions to long-term data survivability rest on scalable architectures

  1. Low-cost and high-capacity short-range optical interconnects using graded-index plastic optical fiber

    NARCIS (Netherlands)

    Tangdiongga, E.; Yang, H.; Lee, S.C.J.; Okonkwo, C.M.; Boom, van den H.P.A.; Randel, S.; Koonen, A.M.J.

    2010-01-01

    We demonstrate a transmission rate of 51.8 Gb/s over 100-meters of perfluorinated multimode graded-index plastic optical fiber using discrete multitone modulation. The results prove suitability of plastic fibers for low-cost high-capacity optical interconnects.

  2. Spongelike Nanosized Mn 3 O 4 as a High-Capacity Anode Material for Rechargeable Lithium Batteries

    KAUST Repository

    Gao, Jie; Lowe, Michael A.; Abruña, Héctor D.

    2011-01-01

    Mn3O4 has been investigated as a high-capacity anode material for rechargeable lithium ion batteries. Spongelike nanosized Mn 3O4 was synthesized by a simple precipitation method and characterized by powder X-ray diffraction, Raman scattering

  3. Amine-Functionalized Amino Acid-based Ionic Liquids as Efficient and High-Capacity Absorbents for CO2

    DEFF Research Database (Denmark)

    Shunmugavel, Saravanamurugan; Kunov-Kruse, Andreas Jonas; Fehrmann, Rasmus

    2014-01-01

    Ionic liquids (ILs) comprised of ammonium cations and anions of naturally occurring amino acids containing an additional amine group (e.g., lysine, histidine, asparagine, and glutamine) were examined as high-capacity absorbents for CO2. An absorption capacity of 2.1 mol CO2 per mol of IL (3.5 mol...

  4. Post-9/11 cancer incidence in World Trade Center-exposed New York City firefighters as compared to a pooled cohort of firefighters from San Francisco, Chicago and Philadelphia (9/11/2001-2009)

    Science.gov (United States)

    Moir, William; Zeig-Owens, Rachel; Daniels, Robert D; Hall, Charles B; Webber, Mayris P; Jaber, Nadia; Yiin, James H; Schwartz, Theresa; Liu, Xiaoxue; Vossbrinck, Madeline; Kelly, Kerry; Prezant, David J

    2016-01-01

    Background We previously reported a modest excess of cancer cases in World Trade Center (WTC) exposed firefighters as compared with the general population. This study aimed to separate the potential carcinogenic effects of firefighting and WTC-exposure by using a cohort of non-WTC-exposed firefighters as the referent group. Methods Relative rates (RRs) for all cancers combined and individual cancer subtypes from 9/11/2001-12/31/2009 were modelled using Poisson regression comparing 11,457 WTC-exposed firefighters to 8,220 non-WTC-exposed firefighters from San Francisco, Chicago, and Philadelphia. Results Compared with non-WTC-exposed firefighters, there was no difference in the RR of all cancers combined for WTC-exposed firefighters (RR=0.96, 95% CI: 0.83–1.12). Thyroid cancer was significantly elevated (RR=3.82, 95% CI: 1.07–20.81) over the entire study; this was attenuated (RR=3.43, 95% CI: 0.94–18.94) and non-significant in a secondary analysis controlling for possible surveillance bias. Prostate cancer was elevated during the latter half (1/1/2005-12/31/2009; RR=1.38, 95% CI: 1.01–1.88). Conclusions Further follow-up is needed with this referent population to assess the relationship between WTC-exposure and cancers with longer latency periods. PMID:27582474

  5. SLC2A9 is a high-capacity urate transporter in humans.

    Directory of Open Access Journals (Sweden)

    Mark J Caulfield

    2008-10-01

    ] 0.9 to 1.05, p > 0.33 by meta-analysis of an SLC2A9 variant in six case-control studies including 11,897 participants. In a separate meta-analysis of four population studies including 11,629 participants we found no association of SLC2A9 with systolic (effect size -0.12 mm Hg, 95% CI -0.68 to 0.43, p = 0.664 or diastolic blood pressure (effect size -0.03 mm Hg, 95% CI -0.39 to 0.31, p = 0.82.This study provides evidence that SLC2A9 splice variants act as high-capacity urate transporters and is one of the first functional characterisations of findings from genome-wide association scans. We did not find an association of the SLC2A9 gene with blood pressure in this study. Our findings suggest potential pathogenic mechanisms that could offer a new drug target for gout.

  6. Self-reported cardiac risks and interest in risk modification among volunteer firefighters: a survey-based study.

    Science.gov (United States)

    Scanlon, Patrick; Ablah, Elizabeth

    2008-12-01

    Coronary heart disease causes approximately 45% of firefighter deaths annually. Although firefighters have clinically significant cardiac risks, a paucity of research and data exists. To evaluate firefighters' cardiac risk factors as well as their motivation to resolve these risk factors. During a 3-month period, volunteer firefighters representing the 79 fire departments serving Nassau and Suffolk counties in Long Island, NY, were asked to complete a nonvalidated, 19-item questionnaire regarding their health habits, medical history, and demographics. A total of 730 surveys were returned among a potential study population of 20,590 volunteer firefighters. More than three-quarters of respondents met the criteria for being overweight or obese, and nearly 40% reported having high blood pressure, high cholesterol, or both. Most respondents expressed at least some interest in attending a fire department-sponsored health lecture and participating in a fitness program. Firefighters expressed desire to learn more about risk factor modifications and have fire departments take a more active role in helping firefighters improve their health. The effectiveness of resources and intervention programs should be assessed.

  7. Review of the health effects of wildland fire smoke on wildland firefighters and the public

    Science.gov (United States)

    Olorunfemi Adetona; Timothy E. Reinhardt; Joe Domitrovich; George Broyles; Anna M. Adetona; Michael T. Kleinman; Roger D. Ottmar; Luke P. Naeher

    2016-01-01

    Each year, the general public and wildland firefighters in the US are exposed to smoke from wildland fires. As part of an effort to characterize health risks of breathing this smoke, a review of the literature was conducted using five major databases, including PubMed and MEDLINE Web of Knowledge, to identify smoke components that present the highest hazard potential,...

  8. Analysis of working conditions focusing on biological risk: firefighters in Campo Grande, MS, Brazil.

    Science.gov (United States)

    Contrera-Moreno, Luciana; de Andrade, Sonia Maria Oliveira; Motta-Castro, Ana Rita Coimbra; Pinto, Alexandra Maria Almeida Carvalho; Salas, Frederico Reis Pouso; Stief, Alcione Cavalheiros Faro

    2012-01-01

    Firefighters are exposed to a wide range of risks, among them, biological risk. The objective was to analyze working conditions of firefighters in the city of Campo Grande, MS, Brazil, focusing on risk conditions of exposure to biological material. Three hundred and seven (307) firefighters were interviewed for data collection and observed for ergonomic job analysis (AET). 63.5% of the firefighters suffered some kind of job related accident with blood or body fluids. Statistically significant association was found between having suffered accidents at work and incomplete use of personal protective equipment (PPE). About AET regarding the biological risks, 57.1% of all patients had blood or secretions, which corresponds in average to 16.0% of the total work time, based on a working day of 24 h. Besides biological risks, other stressing factors were identified: emergency and complexity of decision, high responsibility regarding patients and environment, and conflicts. Health promotion and accident prevention actions must be emphasized as measures to minimize these risks.

  9. Spirometry and impulse oscillometry (IOS) for detection of respiratory abnormalities in metropolitan firefighters.

    NARCIS (Netherlands)

    Schermer, T.R.J.; Malbon, W.; Newbury, W.; Holton, C.; Smith, M.; Morgan, M.; Crockett, A.

    2010-01-01

    BACKGROUND AND OBJECTIVE: As firefighters are at increased risk of adverse health effects, periodic examination of their respiratory health is important. The objective of this study was to establish whether the use of impulse oscillometry (IOS) reveals respiratory abnormalities in metropolitan

  10. Fire characteristics associated with firefighter injury on large federal wildland fires.

    Science.gov (United States)

    Britton, Carla; Lynch, Charles F; Torner, James; Peek-Asa, Corinne

    2013-02-01

    Wildland fires present many injury hazards to firefighters. We estimate injury rates and identify fire-related factors associated with injury. Data from the National Interagency Fire Center from 2003 to 2007 provided the number of injuries in which the firefighter could not return to his or her job assignment, person-days worked, and fire characteristics (year, region, season, cause, fuel type, resistance to control, and structures destroyed). We assessed fire-level risk factors of having at least one reported injury using logistic regression. Negative binomial regression was used to examine incidence rate ratios associated with fire-level risk factors. Of 867 fires, 9.5% required the most complex management and 24.7% required the next-highest level of management. Fires most often occurred in the western United States (82.8%), during the summer (69.6%), caused by lightening (54.9%). Timber was the most frequent fuel source (40.2%). Peak incident management level, person-days of exposure, and the fire's resistance to control were significantly related to the odds of a fire having at least one reported injury. However, the most complex fires had a lower injury incidence rate than less complex fires. Although fire complexity and the number of firefighters were associated with the risk for at least one reported injury, the more experienced and specialized firefighting teams had lower injury incidence. Copyright © 2013 Elsevier Inc. All rights reserved.

  11. 33 CFR 155.4050 - Ensuring that the salvors and marine firefighters are adequate.

    Science.gov (United States)

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Ensuring that the salvors and marine firefighters are adequate. 155.4050 Section 155.4050 Navigation and Navigable Waters COAST GUARD..., water turbidity, water depth, sea state and temperature extremes). (13) Resource provider has the...

  12. 24 CFR 291.530 - Eligible firefighter/emergency medical technicians.

    Science.gov (United States)

    2010-04-01

    ... medical technicians. 291.530 Section 291.530 Housing and Urban Development Regulations Relating to Housing... medical technicians. A person qualifies as a firefighter/emergency medical technician for the purposes of... technician by a fire department or emergency medical services responder unit of the federal government, a...

  13. The health of volunteer firefighters three years after a technological disaster.

    NARCIS (Netherlands)

    Morren, M.; IJzermans, C.J.; Nispen, R.M.A. van; Wevers, S.J.M.

    2005-01-01

    On May 13, 2000, a firework depot exploded in a residential area of the city of Enschede, The Netherlands. Many disaster workers responded, including volunteer firefighters, a group that has received little attention in disaster research. This study examined the presence of health problems in

  14. Occupational Stress and Mental Health Symptoms: Examining the Moderating Effect of Work Recovery Strategies in Firefighters.

    Science.gov (United States)

    Sawhney, Gargi; Jennings, Kristen S; Britt, Thomas W; Sliter, Michael T

    2017-06-12

    The goal of this research was to examine the moderating effect of work recovery strategies on the relationship between occupational stress experienced by firefighters and mental health symptoms. Work recovery strategies were identified through semistructured interviews with 20 firefighters and a literature search on recovery strategies. A total of 7 work recovery strategies emerged using the 2 methods: work-related talks, stress-related talks, time with coworkers/supervisor, exercise, recreational activities, relaxation, and mastery experiences. Using a prospective study design with a 1-month time interval in a sample of 268 firefighters, experienced occupational stress at Time 1 was positively related to mental health symptoms at Time 2. In addition, with the exception of spending time with coworkers/supervisor, exercise and mastery experiences, recovery strategies at Time 1 were negatively related to mental health symptoms at Time 2. Lastly, all work recovery strategies, except stress-related talks and relaxation, moderated the relationship between experienced occupational stress at Time 1 and mental health symptoms at Time 2. Specifically, the positive relationship between experienced occupational stress and mental health symptoms was stronger when firefighters engaged in low, rather than high, work recovery strategies. Implications for research and practice are discussed. (PsycINFO Database Record (c) 2017 APA, all rights reserved).

  15. STS-31 crew training: firefighting, food tasting, EVA prep and post

    Science.gov (United States)

    1990-03-01

    The Space Shuttle crew is shown lighting a pond of gasoline and then performing firefighting tasks. The crew is also shown tasting food including lemonade, chicken casserole, and tortillas, and performing extravehicular activity (EVA) equipment checkouts in the CCT middeck and airlock.

  16. Analysis of Moisture Evaporation from Underwear Designed for Fire-Fighters

    Directory of Open Access Journals (Sweden)

    Elena Onofrei

    2015-03-01

    Full Text Available In this study we analysed the effect of moisture on the thermal protective performance of fire-fighter clothing in case of routine fire-fighting conditions. In the first stage of this research we investigated simultaneous heat and moisture transfer through a single-layer fabric, used as underwear for fire-fighters, at different moisture conditions. In the second stage of the study, the underwear in dry and wet state was tested together with protective clothing systems for fire-fighter consisting of three or four layers. It was found that during the evaporation of the moisture, a temperature plateau appeared during which temperatures hardly rose. The energy consumption used for the phase change of moisture located in the assembly dominated the heat transfer process as long as there was moisture present. As soon as all water had evaporated, the temperatures approached the temperatures measured for dry samples. The moisture within the clothing assembly did not lead to increased temperatures compared with the measurements with dry samples. This research has confirmed that moisture can positively affect the thermal protection of a clothing system.

  17. Impact of a supervised worksite exercise program on back and core muscular endurance in firefighters.

    Science.gov (United States)

    Mayer, John M; Quillen, William S; Verna, Joe L; Chen, Ren; Lunseth, Paul; Dagenais, Simon

    2015-01-01

    Low back pain is a leading cause of disability in firefighters and is related to poor muscular endurance. This study examined the impact of supervised worksite exercise on back and core muscular endurance in firefighters. A cluster randomized controlled trial was used for this study. The study occurred in fire stations of a municipal fire department (Tampa, Florida). Subjects were 96 full-duty career firefighters who were randomly assigned by fire station to exercise (n = 54) or control (n = 42) groups. Exercise group participants completed a supervised exercise targeting the back and core muscles while on duty, two times per week for 24 weeks, in addition to their usual fitness regimen. Control group participants continued their usual fitness regimen. Back and core muscular endurance was assessed with the Biering-Sorensen test and plank test, respectively. Changes in back and core muscular endurance from baseline to 24 weeks were compared between groups using analysis of covariance and linear mixed effects models. After 24 weeks, the exercise group had 12% greater (p = .021) back muscular endurance and 21% greater (p = .0006) core muscular endurance than did the control group. The exercise intervention did not disrupt operations or job performance. A supervised worksite exercise program was safe and effective in improving back and core muscular endurance in firefighters, which could protect against future low back pain.

  18. Risk perception of different emergencies in a sample of European firefighters.

    Science.gov (United States)

    Prati, Gabriele; Pietrantoni, Luca; Saccinto, Elisa; Kehl, Doris; Knuth, Daniela; Schmidt, Silke

    2013-01-01

    Firefighters frequently incur injuries while providing emergency services. Risk perception has been found to be associated with injury and safety behavior. This study examined risk perception of different emergency situations among firefighters. Along with risk perceptions, we investigated the role of practical experience, perceived training, tenure, and acute stress related to different emergency situations. Participants were a sample of 1324 firefighters from Germany and Italy. A questionnaire was administered to participants on risk perceptions, practical experience, perceived training, tenure, and acute stress. The results showed that different levels of risk perception are related to different practical experience, acute stress reactions, and training. Higher risk perception was associated with higher perceived training, practical experience, and acute stress reactions. A significant difference was found between the German and the Italian sample in risk perceptions. More specifically the Italian sample perceived disasters (e.g., earthquakes) as more risky. Moreover, there were some differences in perceived training and practical experience about the different emergency situations, in the two samples. The results underline the importance of considering organizational factors in the prediction of risk perception among firefighters.

  19. Firefighter Safety Zone: The effect of terrain slope of separation distance

    Science.gov (United States)

    Bret Butler; Jason Forthofer

    2010-01-01

    Perhaps one of the most critical decisions made on wildland fires is the identification of suitable safety zones for firefighters during daily fire management operations. To be effective (timely, repeatable, and accurate), these decisions rely on good training and good judgement. The current safety zone guidelines used in the US (see fig. 1) and published in the...

  20. Validation of the Athens Insomnia Scale for screening insomnia in South Korean firefighters and rescue workers.

    Science.gov (United States)

    Jeong, Hyeonseok S; Jeon, Yujin; Ma, Jiyoung; Choi, Yera; Ban, Soonhyun; Lee, Sooyeon; Lee, Bora; Im, Jooyeon Jamie; Yoon, Sujung; Kim, Jieun E; Lim, Jae-Ho; Lyoo, In Kyoon

    2015-10-01

    Sleep problems are a major cause of occupational stress in firefighters and rescue workers. We evaluated the psychometric properties of the Athens Insomnia Scale (AIS) among South Korean firefighters and rescue workers. Structured clinical interviews and self-report questionnaires were administered to 221 firefighters and rescue workers. The Pittsburgh Sleep Quality Index (PSQI), Insomnia Severity Index (ISI), Epworth Sleepiness Scale (ESS), Short-Form 36-item Health Survey (SF36), and Alcohol Use Disorder Identification Test-Consumption (AUDIT-C) were used to examine convergent and divergent validity. Test-retest reliability was calculated from a subsample (n = 24). Analysis of internal consistency, factor analysis, and receiver operator characteristic curve analysis were conducted. Cronbach's alpha was 0.88. The mean item-total correlation coefficient was 0.73. The test-retest reliability was excellent (ICC = 0.94). Significant correlations of the AIS with the PSQI, ISI, ESS, and SF36 confirmed convergent validity. Nonsignificant associations of the AIS with the AUDIT-C and socioeconomic status showed divergent validity. Factor analysis revealed a one-factor structure. For groups with different symptom severity, group-specific cutoff scores which may improve positive predictive values were suggested. The AIS may be a useful tool with good reliability and validity for screening insomnia symptoms in firefighters and rescue workers.

  1. 5 CFR 842.405 - Air traffic controllers, firefighters, law enforcement officers, and nuclear materials couriers.

    Science.gov (United States)

    2010-01-01

    ... 5 Administrative Personnel 2 2010-01-01 2010-01-01 false Air traffic controllers, firefighters, law enforcement officers, and nuclear materials couriers. 842.405 Section 842.405 Administrative Personnel OFFICE OF PERSONNEL MANAGEMENT (CONTINUED) CIVIL SERVICE REGULATIONS (CONTINUED) FEDERAL EMPLOYEES RETIREMENT SYSTEM-BASIC ANNUITY Computations ...

  2. Indicator Systems for School and Teacher Evaluation: Fire-Fighting It Is!

    Science.gov (United States)

    Fitz-Gibbon, C. T.

    In 1979, Gene Glass suggested that it might not be possible to evaluate schools nor to create widely applicable research findings, but that the complexity of education was such that merely "fire-fighting," establishing monitoring systems to alert about educational events, was the best approach. In the United Kingdom, monitoring systems…

  3. Career stages in wildland firefighting: Implications for voice in risky situations

    Science.gov (United States)

    Alexis Lewis; Troy E. Hall; Anne Black

    2011-01-01

    Avoidance of injury and death on the fireline may depend on firefighters voicing their concerns, but often this does not occur. Reasons for employee reticence identified in the literature include a perception of various personal costs or a belief that raising concerns is futile. Additionally, the social context may play a significant role. In a qualitative study using...

  4. A practical cooling strategy for reducing the physiological strain associated with firefighting activity in the heat.

    Science.gov (United States)

    Barr, D; Gregson, W; Sutton, L; Reilly, T

    2009-04-01

    The aim of this study was to establish whether a practical cooling strategy reduces the physiological strain during simulated firefighting activity in the heat. On two separate occasions under high ambient temperatures (49.6 +/- 1.8 degrees C, relative humidity (RH) 13 +/- 2%), nine male firefighters wearing protective clothing completed two 20-min bouts of treadmill walking (5 km/h, 7.5% gradient) separated by a 15-min recovery period, during which firefighters were either cooled (cool) via application of an ice vest and hand and forearm water immersion ( approximately 19 degrees C) or remained seated without cooling (control). There was no significant difference between trials in any of the dependent variables during the first bout of exercise. Core body temperature (37.72 +/- 0.34 vs. 38.21 +/- 0.17 degrees C), heart rate (HR) (81 +/- 9 vs. 96 +/- 17 beats/min) and mean skin temperature (31.22 +/- 1.04 degrees C vs. 33.31 +/- 1 degrees C) were significantly lower following the recovery period in cool compared with control (p second bout of activity in cool compared to control. Mean skin temperature, HR and thermal sensation were significantly lower during bout 2 in cool compared with control (p < 0.05). It is concluded that this practical cooling strategy is effective at reducing the physiological strain associated with demanding firefighting activity under high ambient temperatures.

  5. Physiological and Perceived Effects of Forearm or Head Cooling During Simulated Firefighting Activity and Rehabilitation

    Science.gov (United States)

    Yeargin, Susan; McKenzie, Amy L.; Eberman, Lindsey E.; Kingsley, J. Derek; Dziedzicki, David J.; Yoder, Patrick

    2016-01-01

    Context: Cooling devices aim to protect firefighters by attenuating a rise in body temperature. Devices for head cooling (HC) while firefighting and forearm cooling (FC) during rehabilitation (RHB) intervals are commonly marketed, but research regarding their efficacy is limited. Objective: To investigate the physiological and perceived effects of HC and FC during firefighting drills and RHB. Design: Randomized controlled clinical trial. Setting: Firefighter training center. Patients or Other Participants: Twenty-seven male career firefighters (age = 39 ± 7 years; height = 169 ± 7 cm; weight = 95.4 ± 16.8 kg). Intervention(s): Firefighters were randomly assigned to 1 condition: HC (n = 9), in which participants completed drills wearing a cold gel pack inside their helmet; FC (n = 8), in which participants sat on a collapsible chair with water-immersion arm troughs during RHB; or control (n = 10), in which participants used no cooling devices. Firefighters completed four 15-minute drills (D1−D4) wearing full bunker gear and breathing apparatus. Participants had a 15-min RHB after D2 (RHB1) and D4 (RHB2). Main Outcome Measure(s): Change (Δ) in gastrointestinal temperature (TGI), heart rate (HR), physiological strain index, and perceived thermal sensation. Results: The TGI increased similarly in the HC and control groups, respectively (D1: 0.57°C ± 0.41°C, 0.73°C ± 0.30°C; D2: 0.92°C ± 0.28°C, 0.85°C ± 0.27°C; D3: −0.37°C ± 0.34°C, −0.01°C ± 0.72°C; D4: 0.25°C ± 0.42°C, 0.57°C ± 0.26°C; P > .05). The ΔHR, Δ physiological strain index, and Δ thermal sensation were similar between the HC and control groups during drills (P > .05). The FC group demonstrated a decreased TGI compared with the control group after RHB1 (−1.61°C ± 0.35°C versus −0.23°C ± 0.34°C; P .05). Conclusions: The HC did not attenuate rises in physiological or perceptual variables during firefighting drills. The FC effectively reduced TGI and the

  6. BALANCE ABILITIES OF WORKERS IN PHYSICALLY DEMANDING JOBS: WITH SPECIAL REFERENCE TO FIREFIGHTERS OF DIFFERENT AGES

    Directory of Open Access Journals (Sweden)

    Anne Punakallio

    2005-05-01

    Full Text Available The objectives of the present study were to investigate the associations between balance abilities and age, occupation and the use of fire-protective equipment (FPE in different visual conditions, and the associations of slip and fall risk with balance abilities among workers in physically demanding jobs, especially among workers in fire and rescue work. The reliability and predictive values of balance tests in respect to perceived work ability were also studied. The professional firefighters aged 30 to 56-years (n = 29-135, construction workers (n = 52, home care workers (n = 66 and nursing workers (n = 51 aged 23 to 61 years participated in this study. The data were obtained with balance tests with the use of a force platform, functional balance tests, slipping tests and questionnaires. In one study the balance tests were carried out with and without FPE. The slipping tests with FPE were carried out on a straight 8-m long path that had one area covered by water and detergent or glycerol. Perceived work ability at baseline and after a 3-year follow-up was determined with the use of the work ability index (WAI. In the reliability study, the dynamic balance tests were repeated six times in two testing periods at an interval of 2 months. The results indicated that the balance abilities of firefighters over 49 years of age were significantly poorer than those of firefighters in the age groups of <40 and 40-49 years. The decline of balance abilities among construction, home care and nursing workers was not as consistent. Postural balance was also more harmfully affected among the older firefighters (43-56 years than among the younger ones (33-38 years by the use of FPE without visual input. Self-contained breathing apparatus was the most significant single piece of FPE to impair balance in both groups. Furthermore, fast and controlled performance in the dynamic stability test based on visual feedback was related to smaller slip and fall risk with

  7. Examining Physical and Sexual Abuse Histories as Correlates of Suicide Risk Among Firefighters.

    Science.gov (United States)

    Hom, Melanie A; Matheny, Natalie L; Stanley, Ian H; Rogers, Megan L; Cougle, Jesse R; Joiner, Thomas E

    2017-12-01

    Research indicates that physical and sexual abuse are associated with increased suicide risk; however, these associations have not been investigated among firefighters-an occupational group that has been shown to be at elevated suicide risk. This study examined whether physical and sexual abuse histories are associated with (a) career suicide ideation, plans, and attempts; and (b) current suicide risk (controlling for theoretically relevant symptoms) in this occupational group. A sample of 929 U.S. firefighters completed self-report surveys that assessed lifetime history of physical and sexual abuse; career suicide ideation, plans, and attempts; current suicide risk; and theoretically relevant symptoms. Logistic regression analyses revealed that individuals who reported a history of physical abuse were significantly more likely to report career suicide ideation, adjusted odds ratio [AOR] = 6.12, plans, AOR = 13.05, and attempts, AOR = 23.81, than those who did not. A similar pattern of findings emerged for individuals who reported a sexual abuse history, AORs = 7.83, 18.35, and 29.58 respectively. Linear regression analyses revealed that physical and sexual abuse histories each significantly predicted current suicide risk, even after controlling for theoretically relevant symptoms and demographics, pr 2 = .07 and .06, respectively. Firefighters with a history of physical and/or sexual abuse may be at increased risk for suicidal thoughts and behaviors. A history of physical and sexual abuse were each significantly correlated with current suicide risk in this population, even after accounting for the effects of theoretically relevant symptoms. Thus, when conceptualizing suicide risk among firefighters, factors not necessarily related to one's firefighter career should be considered. Copyright © 2017 International Society for Traumatic Stress Studies.

  8. Deployment of an Advanced Electrocardiographic Analysis (A-ECG) to Detect Cardiovascular Risk in Career Firefighters

    Science.gov (United States)

    Dolezal, B. A.; Storer, T. W.; Abrazado, M.; Watne, R.; Schlegel, T. T.; Batalin, M.; Kaiser, W.; Smith, D. L.; Cooper, C. B.

    2011-01-01

    INTRODUCTION: Sudden cardiac death is the leading cause of line of duty death among firefighters, accounting for approximately 45% of fatalities annually. Firefighters perform strenuous muscular work while wearing heavy, encapsulating personal protective equipment in high ambient temperatures, under chaotic and emotionally stressful conditions. These factors can precipitate sudden cardiac events like myocardial infarction, serious dysrhythmias, or cerebrovascular accidents in firefighters with underlying cardiovascular disease. PURPOSE: The purpose of this study was to deploy and then evaluate the contribution of resting advanced ECG (A-ECG) in addition to other screening tools (family history, lipid profiles, and cardiopulmonary exercise tests, XT) in assessment of an individual fs cardiac risk profile. METHODS: Forty-four career firefighters were recruited to perform comprehensive baseline assessments including tests of aerobic performance, fasting lipids and glucose. Five-min resting 12-lead A-ECGs were obtained in a subset of firefighters (n=21) and transmitted over a secure networked system to a NASA physician collaborator. Using myocardial perfusion and other imaging as the gold standard, A-ECG scoring has been proven useful in accurately identifying a number of cardiac pathologies including coronary artery disease (CAD), left ventricular hypertrophy, hypertrophic cardiomyopathy, and non-ischemic and ischemic cardiomyopathy. RESULTS: Subjects f mean (SD) age was 43 (8) years, weight 91 (13) kg, and BMI 28 (3) kg/m2. Fifty-one percent of subjects had .3 cardiovascular risk factors. One subject had ST depression on XT ECG, at least one positive A-ECG score for CAD, and documented CAD based on cardiology referral. While all other subjects, including those with fewer risk factors, higher aerobic fitness, and normal exercise ECGs, were classified as healthy by A-ECG, there was no trend for association between risk factors and any of 20 A-ECG parameters in the

  9. Job stress and its related factors in Tehran firefighters in year 2000

    Directory of Open Access Journals (Sweden)

    Yazdi SM

    2001-11-01

    Full Text Available Job stress results from a mismatch between job requirements and capabilities, resources, or needs of the worker. Physiological, psychological and behavioral outcomes caused by job stress not only hurt the person but also impose expensive costs on organizations. Firefighting is a job that exposes workers to job stress. The purpose of this study is to determine the level of job stress and some related factors in firefighters of Tehran safety services and firefighters organization. This cross sectional study includes 155 male firefighters whom had selected randomly. In this research we used Leiden University Questionnaire. Also Karasek Questionnaire is used for classification of workers according to karasek’s model. Collected data were analyzed by spss9 software. The final grade of firefighter’s job stress shows a significant positive relationship with second job and a significant negative relationship with age. The level of job satisfaction have a significant negative relationship with job insecurity and lack of meaningfulness, and a significant positive relationship with skill discretion, social support supervisor and social support co-workers. According to karasek classification this job is grouped in active not in high strain grup. The highest level of job stress was seen in physical exertion and hazardous exposure factors. Also in work and time pressure factor, job stress level is high. But job stress is in a moderate or low level in other factors. The level of job stress in younger firefighters and in individuals with a second job indicate a significant increase. However, in western country’s studies, this job is classified as high-strain but in this research it is classified as active group.

  10. The Effects of Injury and Accidents on Self-rated Depression in Male Municipal Firefighters

    Science.gov (United States)

    Chung, Yun Kyung

    2011-01-01

    Objectives The present study aims to determine the causal relationship between self-rated depression and experiences of injury and accidents in municipal firefighters. Methods A panel survey of 186 municipal firefighters measured with depressive symptoms according to the Beck's depression index (BDI) was conducted. The effects of job-related injuries and accidents were evaluated using self-administered questionnaires that were taken once in a 12-month period from 2005 to 2006. Firefighters were classified into the Depression Group or Control Group based on follow-up BDI results with a cutoff level that was set to having "over mild depression." Results The depression Group was comprised of 17 (9.1%) workers, including 9 firefighters who met had sufficient BDI scores twice in the 2-year test period and newly sufficient BDI scores in the follow-up test. A significantly higher number of subjects in the Depression Group experienced injuries and accidents in the 2-year test period as compared to the Control Group (15.4% vs. 1.5%, p=0.04). Firefighters who experienced injuries and accidents in the 2-year test period had a 7.4 times higher risk of being in the Depression Group than those who had not. As compared to accidents, near-miss accidents revealed stronger risks related to being classified as in the Depression group (adjusted odds ratio [OR] = 4.58, 95% confidence interval [CI] = 1.15-18.18 vs. Adjusted OR = 4.22, 95% CI = 1.08-16.58). Conclusion The above results suggest that we should establish an effective program to promote mental health for groups at high risk for self-rated depression, including persons who have experienced consecutive injuries and accidents as well as near-miss injuries. PMID:22953198

  11. Morphology control of ordered mesoporous carbons for high capacity lithium sulfur batteries

    Energy Technology Data Exchange (ETDEWEB)

    Schuster, Joerg David

    2011-06-07

    The focus of this thesis concerns the morphology control of ordered mesoporous carbon (OMC) materials. Ordered mesoporous carbons with diverse morphologies, that are thin films, fibers - embedded in anodic alumina membranes and free-standing - or spherical nanoparticles, have been successfully prepared by soft-templating procedures. The mechanisms of structure formation and processing were investigated with in-situ SAXS measurements and their application in high capacity lithium-sulfur batteries was successfully tested in cooperation with Guang He and Linda Nazar from the University of Waterloo in Canada. The Li-S batteries receive increasing attention due to their high theoretical energy density which is 3 to 5 times higher than from lithium-ion batteries. For this type of battery the specific pore volume is crucial for the content of the active component (sulfur) in the cathode and therefore correlates with the capacity and gravimetric energy density of the battery. At first, mesoporous thin films with 2D-hexagonal structure were obtained through organic-organic self-assembly of a preformed oligomeric resol precursor and the triblock copolymer template Pluronic P123. The formation of a condensed-wall material through thermopolymerization of the precursor oligomers resulted in mesostructured phenolic resin films. Subsequent decomposition of the surfactant and partial carbonization were achieved through thermal treatment in inert atmosphere. The films were crack-free with tunable homogenous thicknesses, and showed either 2D-hexagonal or lamellar mesostructure. An additional, yet unknown 3D-mesostructure was also found. In the second part, cubic and circular hexagonal mesoporous carbon phases in the confined environment of tubular anodic alumina membrane (AAM) pores were obtained by self-assembly of the mentioned resol precursor and the triblock copolymer templates Pluronic F127 or P123, respectively. Casting and solvent-evaporation were also followed by

  12. Criminal Use of Assault Weapons and High-Capacity Semiautomatic Firearms: an Updated Examination of Local and National Sources.

    Science.gov (United States)

    Koper, Christopher S; Johnson, William D; Nichols, Jordan L; Ayers, Ambrozine; Mullins, Natalie

    2017-10-02

    Policies restricting semiautomatic assault weapons and large-capacity ammunition magazines are intended to reduce gunshot victimizations by limiting the stock of semiautomatic firearms with large ammunition capacities and other military-style features conducive to criminal use. The federal government banned such weaponry from 1994 to 2004, and a few states currently impose similar restrictions. Recent debates concerning these weapons have highlighted their use in mass shootings, but there has been little examination of their use in gun crime more generally since the expiration of the federal ban. This study investigates current levels of criminal activity with assault weapons and other high-capacity semiautomatics in the USA using several local and national data sources including the following: (1) guns recovered by police in ten large cities, (2) guns reported by police to federal authorities for investigative tracing, (3) guns used in murders of police, and (4) guns used in mass murders. Results suggest assault weapons (primarily assault-type rifles) account for 2-12% of guns used in crime in general (most estimates suggest less than 7%) and 13-16% of guns used in murders of police. Assault weapons and other high-capacity semiautomatics together generally account for 22 to 36% of crime guns, with some estimates upwards of 40% for cases involving serious violence including murders of police. Assault weapons and other high-capacity semiautomatics appear to be used in a higher share of firearm mass murders (up to 57% in total), though data on this issue are very limited. Trend analyses also indicate that high-capacity semiautomatics have grown from 33 to 112% as a share of crime guns since the expiration of the federal ban-a trend that has coincided with recent growth in shootings nationwide. Further research seems warranted on how these weapons affect injuries and deaths from gun violence and how their regulation may impact public health.

  13. Longitudinal Pulmonary Function in Newly Hired, Non-World Trade Center-Exposed Fire Department City of New York Firefighters

    Science.gov (United States)

    Ye, Fen; Hall, Charles B.; Webber, Mayris P.; Cohen, Hillel W.; Dinkels, Michael; Cosenza, Kaitlyn; Weiden, Michael D.; Nolan, Anna; Christodoulou, Vasilios; Kelly, Kerry J.; Prezant, David J.

    2013-01-01

    Background: Few longitudinal studies characterize firefighters’ pulmonary function. We sought to determine whether firefighters have excessive FEV1 decline rates compared with control subjects. Methods: We examined serial measurements of FEV1 from about 6 months prehire to about 5 years posthire in newly hired male, never smoking, non-Hispanic black and white firefighters, hired between 2003 and 2006, without prior respiratory disease or World Trade Center exposure. Similarly defined Emergency Medical Service (EMS) workers served as control subjects. Results: Through June 30, 2011, 940 firefighters (82%) and 97 EMS workers (72%) who met study criteria had four or more acceptable posthire spirometries. Prehire FEV1% averaged higher for firefighters than EMS workers (99% vs 95%), reflecting more stringent job entry criteria. FEV1 (adjusted for baseline age and height) declined by an average of 45 mL/y both for firefighters and EMS workers, with Fire − EMS decline rate differences averaging 0.2 mL/y (CI, −9.2 to 9.6). Four percent of each group had FEV1 less than the lower limit of normal before hire, increasing to 7% for firefighters and 17.5% for EMS workers, but similar percentages of both groups had adjusted FEV1 decline rates ≥ 10%. Mixed effects modeling showed a significant influence of weight gain but not baseline weight: FEV1 declined by about 8 mL/kg gained for both groups. Adjusting for weight change, FEV1 decline averaged 38 mL/y for firefighters and 34 mL/y for EMS workers. Conclusions: During the first 5 years of duty, firefighters do not show greater longitudinal FEV1 decline than EMS control subjects, and fewer of them develop abnormal lung function. Weight gain is associated with a small loss of lung function, of questionable clinical relevance in this fit and active population. PMID:23188136

  14. Impacts of fire, fire-fighting chemicals and post-fire stabilization techniques on the soil-plant system

    OpenAIRE

    Fernández Fernández, María

    2017-01-01

    Forest fires, as well as fire-fighting chemicals, greatly affect the soil-plant system causing vegetation loss, alterations of soil properties and nutrient losses through volatilization, leaching and erosion. Soil recovery after fires depends on the regeneration of the vegetation cover, which protects the soil and prevents erosion. Fire-fighting chemicals contain compounds potentially toxic for plants and soil organisms, and thus their use might hamper the regeneration of burnt ecosystems. In...

  15. Deployment of an Advanced Electrocardiographic Analysis (A-ECG) to Detect Cardiovascular Risk in Career Firefighters

    Science.gov (United States)

    Dolezal, B. A.; Storer, T. W.; Abrazado, M.; Watne, R.; Schlegel, T. T.; Batalin, M.; Kaiser, W.; Smith, D. L.; Cooper, C. B.

    2011-01-01

    INTRODUCTION Sudden cardiac death is the leading cause of line of duty death among firefighters, accounting for approximately 45% of fatalities annually. Firefighters perform strenuous muscular work while wearing heavy, encapsulating personal protective equipment in high ambient temperatures, under chaotic and emotionally stressful conditions. These factors can precipitate sudden cardiac events like myocardial infarction, serious dysrhythmias, or cerebrovascular accidents in firefighters with underlying cardiovascular disease. Screening for cardiovascular risk factors is recommended but not always followed in this population. PHASER is a project charged with identifying and prioritizing risk factors in emergency responders. We have deployed an advanced ECG (A-ECG) system developed at NASA for improved sensitivity and specificity in the detection of cardiac risk. METHODS Forty-four professional firefighters were recruited to perform comprehensive baseline assessments including tests of aerobic performance and laboratory tests for fasting lipid profiles and glucose. Heart rate and conventional 12-lead ECG were obtained at rest and during incremental treadmill exercise testing (XT). In addition, a 5-min resting 12-lead A-ECG was obtained in a subset of firefighters (n=18) and transmitted over a secure networked system to a physician collaborator at NASA for advanced-ECG analysis. This A-ECG system has been proven, using myocardial perfusion and other imaging, to accurately identify a number of cardiac pathologies including coronary artery disease (CAD), left ventricular hypertrophy, hypertrophic cardiomyopathy, non-ischemic cardiomyopathy, and ischemic cardiomyopathy. RESULTS Subjects mean (SD) age was 43 (8) years, weight 91 (13) kg, and BMI of 28 (3) kg/square meter. Maximum oxygen uptake (VO2max) was 39 (9) ml/kg/min. This compares with the 45th %ile in healthy reference values and a recommended standard of 42 ml/kg/min for firefighters. The metabolic threshold (VO

  16. Development of a new biofertilizer with a high capacity for N2 fixation, phosphate and potassium solubilization and auxin production.

    Science.gov (United States)

    Leaungvutiviroj, Chaveevan; Ruangphisarn, Pimtida; Hansanimitkul, Pikul; Shinkawa, Hidenori; Sasaki, Ken

    2010-01-01

    Biofertilizers that possess a high capacity for N(2) fixation (Azotobacter tropicalis), and consist of phosphate solubilizing bacteria (Burkhoderia unamae), and potassium solubilizing bacteria (Bacillus subtilis) and produce auxin (KJB9/2 strain), have a high potential for growth and yield enhancement of corn and vegetables (Chinese kale). For vegetables, the addition of biofertilizer alone enhanced growth 4 times. Moreover, an enhancement of growth by 7 times was observed due to the addition of rock phosphate and K-feldspar, natural mineral fertilizers, in combination with the biofertilizer.

  17. Lithographically encoded polymer microtaggant using high-capacity and error-correctable QR code for anti-counterfeiting of drugs.

    Science.gov (United States)

    Han, Sangkwon; Bae, Hyung Jong; Kim, Junhoi; Shin, Sunghwan; Choi, Sung-Eun; Lee, Sung Hoon; Kwon, Sunghoon; Park, Wook

    2012-11-20

    A QR-coded microtaggant for the anti-counterfeiting of drugs is proposed that can provide high capacity and error-correction capability. It is fabricated lithographically in a microfluidic channel with special consideration of the island patterns in the QR Code. The microtaggant is incorporated in the drug capsule ("on-dose authentication") and can be read by a simple smartphone QR Code reader application when removed from the capsule and washed free of drug. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. An empirical investigation of job and family stressors amongst firefighters in the South African context

    Directory of Open Access Journals (Sweden)

    R M Oosthuizen

    2007-10-01

    Full Text Available The general aim of the research was to theoretically and empirically study and evaluate job and family stressors amongst firefighters in the South African context. This also included an empirical evaluation of the stress symptoms of firefighters. The research was quantitative, consisting of a survey design. Three measuring instruments were used, namely the Experience of Work and Life Circumstances questionnaire, the Stress questionnaire as well as a biographical questionnaire. Task characteristics, organisational functioning, physical working conditions and job equipment, career and social matters, remuneration, fringe benefits and personnel policy were identified as causes of job stress originating within the work situation. Marital dysfunction and divorce, limited time with the family, problems with children, alcohol and drug abuse, lack of exercise, suicide, anger aimed at family members, physical and emotional exhaustion, lonely marital partners, unavailability to help the family when needed and depression were identified as causes of family stress arising outside the work situation.

  19. A WSN-Based Tool for Urban and Industrial Fire-Fighting

    Directory of Open Access Journals (Sweden)

    Aníbal Ollero Baturone

    2012-11-01

    Full Text Available This paper describes a WSN tool to increase safety in urban and industrial fire-fighting activities. Unlike most approaches, we assume that there is no preexisting WSN in the building, which involves interesting advantages but imposes some constraints. The system integrates the following functionalities: fire monitoring, firefighter monitoring and dynamic escape path guiding. It also includes a robust localization method that employs RSSI-range models dynamically trained to cope with the peculiarities of the environment. The training and application stages of the method are applied simultaneously, resulting in significant adaptability. Besides simulations and laboratory tests, a prototype of the proposed system has been validated in close-to-operational conditions.

  20. Firefighter safety for PV systems: Overview of future requirements and protection systems

    DEFF Research Database (Denmark)

    Spataru, Sergiu; Sera, Dezso; Blaabjerg, Frede

    2013-01-01

    for operators during maintenance or fire-fighting. One of the solutions is individual module shutdown by short-circuiting or disconnecting each PV module from the PV string. However, currently no standards have been adopted either for implementing or testing these methods, or doing an evaluation of the module...... shutdown procedures. This paper gives an overview on the most recent fire - and firefighter safety requirements for PV systems, with focus on system and module shutdown systems. Several solutions are presented, analyzed and compared by considering a number of essential characteristics, including......An important and highly discussed safety issue for photovoltaic systems is that, as long as they are illuminated, a high voltage is present at the PV string terminals and cables between the string and inverters, independent of the state of the inverter's dc disconnection switch, which poses a risk...

  1. Expanded access to naloxone among firefighters, police officers, and emergency medical technicians in Massachusetts.

    Science.gov (United States)

    Davis, Corey S; Ruiz, Sarah; Glynn, Patrick; Picariello, Gerald; Walley, Alexander Y

    2014-08-01

    Naloxone is a medication that reverses respiratory depression from opioid overdose if given in time. Paramedics routinely administer naloxone to opioid overdose victims in the prehospital setting, and many states are moving to increase access to the medication. Several jurisdictions have expanded naloxone administration authority to nonparamedic first responders, and others are considering that step. We report here on policy change in Massachusetts, where several communities have equipped emergency medical technicians, law enforcement officers, and firefighters with naloxone.

  2. Twenty-four-hour shift work, depressive symptoms, and job dissatisfaction among Japanese firefighters.

    Science.gov (United States)

    Saijo, Yasuaki; Ueno, Takeji; Hashimoto, Yoshihiro

    2008-05-01

    The influence of a 24-hr shift-work burden on firefighters' mental health has not been fully investigated. The purpose of this study is to clarify the relationships between specific workload items among firefighters engaged in 24-hr shift work and job stress as estimated by the generic job-stress questionnaire on depressive symptoms and job dissatisfaction from the National Institute for Occupational Safety and Health (NIOSH). The subjects were 1,301 firefighters. The questionnaire covered age, gender, job type, job class, marital status, smoking and drinking habits, number of attendances, turnout time, extra work hours, average nap-time, the Center for Epidemiologic Studies Depression Scale (CES-D), and questions from the NIOSH generic job-stress questionnaire, including those on job satisfaction. In multivariate logistic regression analyses, a model that included all variables except the measures from the NIOSH generic job-stress questionnaire showed that shorter nap-time had significant higher odds ratios (ORs) for depressive symptoms and job dissatisfaction, but the significances disappeared in a fully adjusted model. In fully adjusted logistic regression analyses, low quantitative workload, low variance in workload, high intra- and intergroup conflict, low social support from a supervisor, high role conflict and ambiguity, and low self-esteem had significant higher ORs for depressive symptoms and/or job dissatisfaction. Amount of workload, variance in workload, intra- and intergroup conflict, social support from a supervisor, role conflict and ambiguity, and self-esteem were significantly related to depressive symptoms and/or job dissatisfaction among Japanese firefighters. Moreover, inadequate nap-time may affect their mental health. (c) 2008 Wiley-Liss, Inc.

  3. Maximal oxygen consumption, respiratory volume and some related factors in fire-fighting personnel

    Directory of Open Access Journals (Sweden)

    Touraj Khazraee

    2017-01-01

    Full Text Available Background: Firefighters for difficult activities and rescue of damaged people must be in appropriate physical ability. Maximal oxygen capacity is an indicator for diagnosis of physical ability of workers. This study aimed to assess the cardiorespiratory system and its related factors in firefighters. Methods: This study was conducted on 110 firefighters from various stations. An self-administered questionnaire (respiratory disorders questionnaire, Tuxworth-Shahnavaz step test, and pulmonary function test was used to collection of required data. Average of humidity and temperature was 52% and 17°C, respectively. Background average noise levels were between 55 and 65 dB. Data were analyzed using SPSS software (version 19. Results: The mean age of the study participants was 32 ± 6.2 years. The means of forced vital capacity (FVC, forced expiratory volume in 1 s (FEV1, and FEV1/FVC were 92% ±9.4%, 87% ±9.2%, and 80% ±6.1%, respectively. The participants' mean VO2-max was 2.79 ± 0.29 L/min or 37.34 ± 4.27 ml/kg body weight per minute. The results revealed that weight has a direct association with vital capacity (VC, FVC, and peak expiratory flow. In addition, height was directly associated with VC, FVC, and VO2-max (P < 0.05. However, there was an inverse and significant association between height and FEV1/FVC (r = −0.23,P< 0.05. Height, weight, body mass index, and waist circumference were directly associated with VO2-max. Conclusions: The findings of this study showed that the amount of maximum oxygen consumption is close with the proposed range of this parameter among firefighters in other studies. Furthermore, the results of the study revealed that individuals had normal amounts of lung volume index. This issue can be attributed to the appropriate usage of respiratory masks.

  4. The H_6_0Si_6C_5_4 heterofullerene as high-capacity hydrogen storage medium

    International Nuclear Information System (INIS)

    Yong, Yongliang; Zhou, Qingxiao; Li, Xiaohong; Lv, Shijie

    2016-01-01

    With the great success in Si atoms doped C_6_0 fullerene and the well-established methods for synthesis of hydrogenated carbon fullerenes, this leads naturally to wonder whether Si-doped fullerenes are possible for special applications such as hydrogen storage. Here by using first-principles calculations, we design a novel high-capacity hydrogen storage material, H_6_0Si_6C_5_4 heterofullerene, and confirm its geometric stability. It is found that the H_6_0Si_6C_5_4 heterofullerene has a large HOMO-LUMO gap and a high symmetry, indicating it is high chemically stable. Further, our finite temperature simulations indicate that the H_6_0Si_6C_5_4 heterofullerene is thermally stable at 300 K. H_2 molecules would enter into the cage from the Si-hexagon ring because of lower energy barrier. Through our calculation, a maximum of 21 H_2 molecules can be stored inside the H_6_0Si_6C_5_4 cage in molecular form, leading to a gravimetric density of 11.11 wt% for 21H_2@H_6_0Si_6C_5_4 system, which suggests that the hydrogenated Si_6C_5_4 heterofullerene could be suitable as a high-capacity hydrogen storage material.

  5. When High-Capacity Readers Slow Down and Low-Capacity Readers Speed Up: Working Memory and Locality Effects.

    Science.gov (United States)

    Nicenboim, Bruno; Logačev, Pavel; Gattei, Carolina; Vasishth, Shravan

    2016-01-01

    We examined the effects of argument-head distance in SVO and SOV languages (Spanish and German), while taking into account readers' working memory capacity and controlling for expectation (Levy, 2008) and other factors. We predicted only locality effects, that is, a slowdown produced by increased dependency distance (Gibson, 2000; Lewis and Vasishth, 2005). Furthermore, we expected stronger locality effects for readers with low working memory capacity. Contrary to our predictions, low-capacity readers showed faster reading with increased distance, while high-capacity readers showed locality effects. We suggest that while the locality effects are compatible with memory-based explanations, the speedup of low-capacity readers can be explained by an increased probability of retrieval failure. We present a computational model based on ACT-R built under the previous assumptions, which is able to give a qualitative account for the present data and can be tested in future research. Our results suggest that in some cases, interpreting longer RTs as indexing increased processing difficulty and shorter RTs as facilitation may be too simplistic: The same increase in processing difficulty may lead to slowdowns in high-capacity readers and speedups in low-capacity ones. Ignoring individual level capacity differences when investigating locality effects may lead to misleading conclusions.

  6. Fabrication of high-capacity polyelectrolyte brush-grafted porous AAO-silica composite membrane via RAFT polymerization.

    Science.gov (United States)

    Song, Cunfeng; Wang, Meijie; Liu, Xin; Wang, He; Chen, Xiaoling; Dai, Lizong

    2017-09-01

    Surface-initiated reversible addition-fragmentation chain transfer (RAFT) polymerization has been utilized to fabricate high-capacity strong anion-exchange (AEX) membrane for the separation of protein. By means of RAFT polymerization, quaternized poly(3-(methacrylamidomethyl)-pyridine) brushes formed 3-dimensional nanolayers on the surface of porous anodic aluminum oxide (AAO)-silica composite membrane. The surface properties of the membranes were analyzed by SEM, water contact angle, ATR-FTIR, XPS and TGA. To investigate the adsorption performance, the new AEX membranes were applied to recover a model protein, ovalbumin (OVA). High adsorption capacities of 95.8mg/g membranes (static) and 65.3mg/g membranes (dynamic) were obtained at ambient temperature. In the further studies, up to 90% of the adsorbed OVA was efficiently eluted by using phosphate buffer-1M NaCl as elution medium. The successful separation of OVA with high purity from a mixture protein solution was also achieved by using the AEX membranes. The present study demonstrated that under mild reaction condition, RAFT polymerization can be used to fabricate ion-exchange membrane which has many remarkable features, such as high capacity and selectivity, easy elution and so on. Copyright © 2017. Published by Elsevier B.V.

  7. When high-capacity readers slow down and low-capacity readers speed up: Working memory and locality effects

    Directory of Open Access Journals (Sweden)

    Bruno eNicenboim

    2016-03-01

    Full Text Available We examined the effects of argument-head distance in SVO and SOV languages (Spanish and German, while taking into account readers’ working memory capacity and controlling for expectation (Levy, 2008 and other factors. We predicted only locality effects, that is, a slow-down produced by increased dependency distance (Gibson, 2000; Lewis & Vasishth, 2005. Furthermore, we expected stronger locality effects for readers with low working memory capacity. Contrary to our predictions, low-capacity readers showed faster reading with increased distance, while high-capacity readers showed locality effects. We suggest that while the locality effects are compatible with memory-based explanations, the speedup of low-capacity readers can be explained by an increased probability of retrieval failure. We present a computational model based on ACT-R built under the previous assumptions, which is able to give a qualitative account for the present data and can be tested in future research. Our results suggest that in some cases, interpreting longer RTs as indexing increased processing difficulty and shorter RTs as facilitation may be too simplistic: The same increase in processing difficulty may lead to slowdowns in high-capacity readers and speedups in low-capacity ones. Ignoring individual level capacity differences when investigating locality effects may lead to misleading conclusions.

  8. Life cycle environmental impact of high-capacity lithium ion battery with silicon nanowires anode for electric vehicles.

    Science.gov (United States)

    Li, Bingbing; Gao, Xianfeng; Li, Jianyang; Yuan, Chris

    2014-01-01

    Although silicon nanowires (SiNW) have been widely studied as an ideal material for developing high-capacity lithium ion batteries (LIBs) for electric vehicles (EVs), little is known about the environmental impacts of such a new EV battery pack during its whole life cycle. This paper reports a life cycle assessment (LCA) of a high-capacity LIB pack using SiNW prepared via metal-assisted chemical etching as anode material. The LCA study is conducted based on the average U.S. driving and electricity supply conditions. Nanowastes and nanoparticle emissions from the SiNW synthesis are also characterized and reported. The LCA results show that over 50% of most characterized impacts are generated from the battery operations, while the battery anode with SiNW material contributes to around 15% of global warming potential and 10% of human toxicity potential. Overall the life cycle impacts of this new battery pack are moderately higher than those of conventional LIBs but could be actually comparable when considering the uncertainties and scale-up potential of the technology. These results are encouraging because they not only provide a solid base for sustainable development of next generation LIBs but also confirm that appropriate nanomanufacturing technologies could be used in sustainable product development.

  9. The reciprocal relationship between work characteristics and employee burnout and engagement: a longitudinal study of firefighters.

    Science.gov (United States)

    Ângelo, R P; Chambel, M J

    2015-04-01

    The paradigm of this study is positive occupational psychology, with the job demands-resources model as the research model and the Conservation of Resources theory as the general stress theory. The research design analyses the job demands-resources model's dynamic nature with normal and reversed causation effects between work characteristics and psychological well-being among Portuguese firefighters. In addition, we analyse a positive (engagement) dimension and a negative (burnout) dimension in the firefighters' well-being, because previously, studies have merely focused on the strain or stress of these professionals. The research questionnaire was distributed to a sample of 651 firefighters, and a two-wave full panel design was used. Cross-lagged panel analyses indicated that the causal direction of the relationship between organizational demands and burnout is reciprocal. Also, we found that the reciprocal model, including cross-lagged reciprocal relationships between organizational demands/supervisory support and burnout/engagement, respectively, is what fits the data best. Practical implications to develop organizational change programmes and suggestions for future research regarding the promotion of occupational health are discussed. Copyright © 2013 John Wiley & Sons, Ltd.

  10. Analysis of foot clearance in firefighters during ascent and descent of stairs.

    Science.gov (United States)

    Kesler, Richard M; Horn, Gavin P; Rosengren, Karl S; Hsiao-Wecksler, Elizabeth T

    2016-01-01

    Slips, trips, and falls are a leading cause of injury to firefighters with many injuries occurring while traversing stairs, possibly exaggerated by acute fatigue from firefighting activities and/or asymmetric load carriage. This study examined the effects that fatigue, induced by simulated firefighting activities, and hose load carriage have on foot clearance while traversing stairs. Landing and passing foot clearances for each stair during ascent and descent of a short staircase were investigated. Clearances decreased significantly (p < 0.05) post-exercise for nine of 12 ascent parameters and increased for two of eight descent parameters. Load carriage resulted in significantly decreased (p < 0.05) clearance over three ascent parameters, and one increase during descent. Decreased clearances during ascent caused by fatigue or load carriage may result in an increased trip risk. Increased clearances during descent may suggest use of a compensation strategy to ensure stair clearance or an increased risk of over-stepping during descent. Copyright © 2015 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  11. Physical fitness profile of professional Italian firefighters: differences among age groups.

    Science.gov (United States)

    Perroni, Fabrizio; Cignitti, Lamberto; Cortis, Cristina; Capranica, Laura

    2014-05-01

    Firefighters perform many tasks which require a high level of fitness and their personal safety may be compromised by the physiological aging process. The aim of the study was to evaluate strength (bench-press), power (countermovement jump), sprint (20 m) and endurance (with and without Self Contained Breathing Apparatus - S.C.B.A.) of 161 Italian firefighters recruits in relation to age groups (profile for each parameter and to assess differences (p < 0.05) among age groups. Anthropometric values showed an age-effect for height and BMI, while performances values showed statistical differences for strength, power, sprint tests and endurance test with S.C.B.A. Wearing the S.C.B.A., 14% of all recruits failed to complete the endurance test. We propose that the firefighters should participate in an assessment of work capacity and specific fitness programs aimed to maintain an optimal fitness level for all ages. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  12. The Prevalence of Cardiovascular Disease Risk Factors and Obesity in Firefighters

    Directory of Open Access Journals (Sweden)

    Denise L. Smith

    2012-01-01

    Full Text Available Obesity is associated with increased risk of cardiovascular disease (CVD mortality. CVD is the leading cause of duty-related death among firefighters, and the prevalence of obesity is a growing concern in the Fire Service. Methods. Traditional CVD risk factors, novel measures of cardiovascular health and a measurement of CVD were described and compared between nonobese and obese career firefighters who volunteered to participate in this cross-sectional study. Results. In the group of 116 men (mean age 43±8 yrs, the prevalence of obesity was 51.7%. There were no differences among traditional CVD risk factors or the coronary artery calcium (CAC score (criterion measure between obese and nonobese men. However, significant differences in novel markers, including CRP, subendocardial viability ratio, and the ejection duration index, were detected. Conclusions. No differences in the prevalence of traditional CVD risk factors between obese and nonobese men were found. Additionally, CAC was similar between groups. However, there were differences in several novel risk factors, which warrant further investigation. Improved CVD risk identification among firefighters has important implications for both individual health and public safety.

  13. Accuracy of Body Mass Index-defined Obesity Status in US Firefighters

    Directory of Open Access Journals (Sweden)

    Nattinee Jitnarin

    2014-09-01

    Full Text Available Obesity is a significant problem affecting United States (US firefighters. While body mass index (BMI is widely used to diagnose obesity, its use for this occupational group has raised concerns about validity. We examined rates and types of misclassification of BMI-based obesity status compared to body fat percentage (BF% and waist circumference (WC. Male career firefighters (N = 994 from 20 US departments completed all three body composition assessments. Mean BMI, BF%, and WC were 29 kg/m2, 23%, and 97 cm, respectively. Approximately 33% and 15% of BF%- and WC-defined obese participants were misclassified as non-obese (false negatives using BMI, while 8% and 9% of non-obese participants defined by BF% and WC standards were identified as obese (false positives using BMI. When stratified by race/ethnicity, Pacific Islanders showed high rates of false positive misclassification. Precision in obesity classification would be improved by using WC along with BMI to determine firefighters' weight status.

  14. Criticality and fire-fighting - Recent developments at Westinghouse, Springfields Fuels Limited

    International Nuclear Information System (INIS)

    Hill, D. A.; Clemson, P. D.

    2009-01-01

    Fire-fighting advice in criticality-controlled areas has traditionally presented unique challenges to the nuclear industry, primarily because of the introduction of moderators / reflectors from water and foam and the potential rearrangement of materials. In an actual emergency, the decision to use water-based fire extinguishing methods is best influenced by a consensus between the criticality and fire specialists as part of the emergency planning process. A recent review of the fire-fighting arrangements at the site operated by Springfields Fuels Limited (SFL) in Preston in the United Kingdom has identified that more detailed guidance may be valuable relating to the specific areas and materials at risk, particularly to highlight the degree of risk and provide guidance on the risk of criticality if water-based fire extinguishing methods were deemed necessary. This has prompted consideration of a criticality 'Fire Tag' system, consisting of colour coded markers in the area (an immediate visual indicator of both the degree of risk and the appropriate fire-fighting response) and single sheet cards (specific guidance for the areas and materials at risk), with the process supported by appropriate training. The approach is currently being trialled on a small scale, and initial feedback from personnel has been positive. (authors)

  15. Effects of caffeine and menthol on cognition and mood during simulated firefighting in the heat.

    Science.gov (United States)

    Zhang, Yang; Balilionis, Gytis; Casaru, Catalina; Geary, Colleen; Schumacker, Randall E; Neggers, Yasmin H; Curtner-Smith, Matthew D; Richardson, Mark T; Bishop, Phillip A; Green, James M

    2014-05-01

    This study examined the separate effects of caffeine and menthol on cognition and mood during simulated firefighting in the heat. Participants (N = 10) performed three trials in a counterbalanced order, either with 400 mg caffeine, menthol lozenges, or placebo. The simulated firefighting consisted of 2 bouts of 20-min treadmill exercise and one bout of 20-min stepping exercise in the heat with two brief 15-min rest periods between each exercise phase. Exercise induced significant dehydration (>3%) and elevated rectal temperature (>38.9 °C), for all three conditions. Neither caffeine nor menthol reduced perceived exertion compared to placebo (p > 0.05). Mood ratings (i.e., alertness, hedonic tone, tension) significantly deteriorated over time (p memory, and retrieval memory did not alter with treatments or repeated evaluations. Reaction accuracy from a math test remained unchanged throughout the experimental period; reaction time from the math test was significantly faster after exposure to the heat (p < 0.05). It is concluded that, exhaustive exercise in the heat severely impacted mood, but minimally impacted cognition. These treatments failed to show ergogenic benefits in a simulated firefighting paradigm in a hot environment. Copyright © 2013 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  16. The Impact of Firefighter Personal Protective Equipment and Treadmill Protocol on Maximal Oxygen Uptake

    Science.gov (United States)

    Lee, Joo-Young; Bakri, Ilham; Kim, Jung-Hyun; Son, Su-Young; Tochihara, Yutaka

    2015-01-01

    This study investigated the effects of firefighter personal protective equipment (PPE) on the determination of maximal oxygen uptake (VO2max) while using two different treadmill protocols: a progressive incline protocol (PIP) and a progressive speed protocol (PSP), with three clothing conditions (Light-light clothing; Boots-PPE with rubber boots; Shoes-PPE with running shoes). Bruce protocol with Light was performed for a reference test. Results showed there was no difference in VO2max between Bruce Light, PIP Light, and PSP Light. However, VO2max was reduced in Boots and Shoes with shortened maximal performance time (7 and 6 min reduced for PIP Boots and Shoes, respectively; 11 and 9 min reduced for PSP Boots and Shoes, respectively), whereas the increasing rate of VO2 in Boots and Shoes during submaximal exercise was greater compared with Light. Wearing firefighter boots compared with wearing running shoes also significantly affected submaximal VO2 but not VO2max. These results suggest that firefighters’ maximal performance determined from a typical VO2max test without wearing PPE may overestimate the actual performance capability of firefighters wearing PPE. PMID:23668854

  17. Association between job stress and occupational injuries among Korean firefighters: a nationwide cross-sectional study.

    Science.gov (United States)

    Kim, Yeong-Kwang; Ahn, Yeon-Soon; Kim, KyooSang; Yoon, Jin-Ha; Roh, Jaehoon

    2016-11-25

    We aimed to assess the nature of association between job stress and occupational injuries among firefighters in Korea. Cross-sectional study. We conducted a nationwide survey using self-reported questionnaires in South Korea. A survey was conducted among 30 630 firefighters; 25 616 (83.6%) responded. Our study included firefighters who were 20-59 years old. Individuals with occupational injury; high job demands (OR=1.22, 95% CI 1.01 to 1.47) were also associated with the frequency of injuries. Among emergency medical services personnel, high job demands (OR=1.26, 95% CI 1.03 to 1.54), high interpersonal conflicts (OR=1.40, 95% CI 1.19 to 1.66), a poor organisational system (OR=1.55, 95% CI 1.30 to 1.85), lack of reward (OR=1.43, 95% CI 1.21 to 1.69) and a negative workplace environment (OR=1.30, 95% CI 1.10 to 1.54) were associated with the occurrence of occupational injury; low job control (OR=1.20, 95% CI 1.04 to 1.38), high interpersonal conflicts (OR=1.18, 95% CI 1.03 to 1.36), lack of reward (OR=1.17, 95% CI 1.02 to 1.35) and a negative workplace climate (OR=1.16, 95% CI 1.01 to 1.34) were also associated with a greater number of injuries. Among officers, high job demands (OR=1.96, 95% CI 1.35 to 2.85) and a negative workplace environment (OR=1.54, 95% CI 1.13 to 2.10) were associated with the occurrence of occupational injuries; however, there was no significant correlation between job stress and the number of injuries. High job stress among firefighters was associated with both the occurrence of occupational injury, and also with an increased frequency of injuries. Therefore, job stress should be addressed to prevent occupational injuries among firefighters. Published by the BMJ Publishing Group Limited. For permission to use (where not already granted under a licence) please go to http://www.bmj.com/company/products-services/rights-and-licensing/.

  18. Spongelike Nanosized Mn 3 O 4 as a High-Capacity Anode Material for Rechargeable Lithium Batteries

    KAUST Repository

    Gao, Jie

    2011-07-12

    Mn3O4 has been investigated as a high-capacity anode material for rechargeable lithium ion batteries. Spongelike nanosized Mn 3O4 was synthesized by a simple precipitation method and characterized by powder X-ray diffraction, Raman scattering and scanning electron microscopy. Its electrochemical performance, as an anode material, was evaluated by galvanostatic discharge-charge tests. The results indicate that this novel type of nanosized Mn3O4 exhibits a high initial reversible capacity (869 mA h/g) and significantly enhanced first Coulomb efficiency with a stabilized reversible capacity of around 800 mA h/g after over 40 charge/discharge cycles. © 2011 American Chemical Society.

  19. Random oriented hexagonal nickel hydroxide nanoplates grown on graphene as binder free anode for lithium ion battery with high capacity

    Science.gov (United States)

    Du, Yingjie; Ma, Hu; Guo, Mingxuan; Gao, Tie; Li, Haibo

    2018-05-01

    In this work, two-step method has been employed to prepare random oriented hexagonal hydroxide nanoplates on graphene (Ni(OH)2@G) as binder free anode for lithium ion battery (LIB) with high capacity. The morphology, microstructure, crystal phase and elemental bonding have been characterized. When evaluated as anode for LIB, the Ni(OH)2@G exhibited high initial discharge capacity of 1318 mAh/g at the current density of 50 mA/g. After 80 cycles, the capacity was maintained at 834 mAh/g, implying 63.3% remaining. Even the charge rate was increased to 2000 mA/g, an impressive capacity of 141 mAh/g can be obtained, indicating good rate capability. The superior LIB behavior of Ni(OH)2@G is ascribed to the excellent combination between Ni(OH)2 nanoplates and graphene via both covalent chemical bonding and van der Waals interactions.

  20. Topology of genetic associations between regional gray matter volume and intellectual ability: Evidence for a high capacity network.

    Science.gov (United States)

    Bohlken, Marc M; Brouwer, Rachel M; Mandl, René C W; Hedman, Anna M; van den Heuvel, Martijn P; van Haren, Neeltje E M; Kahn, René S; Hulshoff Pol, Hilleke E

    2016-01-01

    Intelligence is associated with a network of distributed gray matter areas including the frontal and parietal higher association cortices and primary processing areas of the temporal and occipital lobes. Efficient information transfer between gray matter regions implicated in intelligence is thought to be critical for this trait to emerge. Genetic factors implicated in intelligence and gray matter may promote a high capacity for information transfer. Whether these genetic factors act globally or on local gray matter areas separately is not known. Brain maps of phenotypic and genetic associations between gray matter volume and intelligence were made using structural equation modeling of 3T MRI T1-weighted scans acquired in 167 adult twins of the newly acquired U-TWIN cohort. Subsequently, structural connectivity analyses (DTI) were performed to test the hypothesis that gray matter regions associated with intellectual ability form a densely connected core. Gray matter regions associated with intellectual ability were situated in the right prefrontal, bilateral temporal, bilateral parietal, right occipital and subcortical regions. Regions implicated in intelligence had high structural connectivity density compared to 10,000 reference networks (p=0.031). The genetic association with intelligence was for 39% explained by a genetic source unique to these regions (independent of total brain volume), this source specifically implicated the right supramarginal gyrus. Using a twin design, we show that intelligence is genetically represented in a spatially distributed and densely connected network of gray matter regions providing a high capacity infrastructure. Although genes for intelligence have overlap with those for total brain volume, we present evidence that there are genes for intelligence that act specifically on the subset of brain areas that form an efficient brain network. Copyright © 2015 Elsevier Inc. All rights reserved.

  1. Bridging the divide between fire safety research and fighting fire safely: How do we convey research innovation to contribute more effectively to wildland firefighter safety?

    Science.gov (United States)

    Theodore Ted Adams; Bret W. Butler; Sara Brown; Vita Wright; Anne Black

    2017-01-01

    Creating a safe workplace for wildland firefighters has long been at the centre of discussion for researchers and practitioners. The goal of wildland fire safety research has been to protect operational firefighters, yet its contributions often fall short of potential because much is getting lost in the translation of peer-reviewed results to potential and intended...

  2. Final Report: DE- FC36-05GO15063, Fundamental Studies of Advanced High-Capacity, Reversible Metal Hydrides

    Energy Technology Data Exchange (ETDEWEB)

    Jensen, Craig [Univ. of Hawaii, Honolulu, HI (United States); McGrady, Sean [Univ. of New Brunswick, Fredericton NB (Canada); Severa, Godwin [Univ. of Hawaii, Honolulu, HI (United States); Eliseo, Jennifer [Univ. of Hawaii, Honolulu, HI (United States); Chong, Marina [Univ. of Hawaii, Honolulu, HI (United States)

    2013-05-31

    The project was component of the US DOE, Metal Hydride Center of Excellence (MHCoE). The Sandia National Laboratory led center was established to conduct highly collaborative and multi-disciplinary applied R&D to develop new reversible hydrogen storage materials that meet or exceed DOE/FreedomCAR 2010 and 2015 system targets for hydrogen storage materials. Our approach entailed a wide variety of activities ranging from synthesis, characterization, and evaluation of new candidate hydrogen storage materials; screening of catalysts for high capacity materials requiring kinetics enhancement; development of low temperature methods for nano-confinement of hydrides and determining its effects on the kinetics and thermodynamics of hydrides; and development of novel processes for the direct re-hydrogenation of materials. These efforts have resulted in several advancements the development of hydrogen storage materials. We have greatly extended the fundamental knowledge about the highly promising hydrogen storage carrier, alane (AlH3), by carrying out the first crystal structure determinations and the first determination of the heats of dehydrogenation of β–AlH3 and γ-AlD3. A low-temperature homogenous organometallic approach to incorporation of Al and Mg based hydrides into carbon aerogels has been developed that that allows high loadings without degradation of the nano-porous scaffold. Nano-confinement was found to significantly improve the dehydrogenation kinetics but not effect the enthalpy of dehydrogenation. We conceived, characterized, and synthesized a novel class of potential hydrogen storage materials, bimetallic borohydrides. These novel compounds were found to have many favorable properties including release of significant amounts of hydrogen at moderate temperatures (75-190 º C). However, in situ IR studies in tandem with thermal gravimetric analysis have shown that about 0.5 equivalents of diborane are released during the

  3. Influence of Lower Extremity Muscle Size and Quality on Stair-Climb Performance in Career Firefighters.

    Science.gov (United States)

    Kleinberg, Craig R; Ryan, Eric D; Tweedell, Andrew J; Barnette, Timothy J; Wagoner, Chad W

    2016-06-01

    The purpose of this study was to examine the influence of lower extremity muscular size and quality on stair-climb performance (SCP) in career firefighters. Forty-six male career firefighters (age = 37.0 ± 7.2 years; stature = 180.2 ± 6.9 cm; body mass = 108.0 ± 19.8 kg) volunteered for this study. Panoramic ultrasound images of the vastus lateralis and rectus femoris were obtained to determine cross-sectional area (CSA) and echo intensity (EI) of each muscle. The CSA of each muscle was then summed together and normalized to body mass (CSA/BM [QCSA]). Additionally, EI was averaged across both muscles (QEI). Participants then performed a timed and weighted SCP assessment where they ascended and descended 26 stairs 4 times as quickly as possible while wearing a weighted vest (22.73 kg) to simulate the weight of their self-contained breathing apparatus and turnout gear. Bivariate correlations and stepwise regression analyses were used to examine the relationships among variables and the relative contributions of QCSA and QEI to SCP. Partial correlations were used to examine the relationship between QCSA and SCP and QEI and SCP while controlling for age and body mass index (BMI). The results indicated that QCSA and QEI were significantly related to SCP before (r = -0.492, p = 0.001; r = 0.363, p = 0.013, respectively) and after accounting for age and BMI (r = -0.324, p = 0.032; r = 0.413, p = 0.005, respectively). Both QCSA and QEI contributed significantly to the prediction of SCP (r = 0.560, p < 0.001). These findings indicate that lower extremity muscle size and quality are important contributors to critical firefighting tasks, which have been shown to be improved with resistance training.

  4. Assessment of exposure to carbon monoxide group of firefighters from fire fighting and rescue units

    Directory of Open Access Journals (Sweden)

    Jadwiga Lembas-Bogaczyk

    2011-03-01

    Full Text Available Firemen threat during fire burning of chemical substances indicated presence of carbon monoxide (CO in all cases. Carbon monoxide causes death of fire. Inhaled through respiratory system, links with hemoglobin, thus blocking transport and distribution of oxygen in the body. This leads to tissue anoxia, which is a direct threat to firefighters’ life. The purpose of this study was to assess the exposure to carbon monoxide of participating firefighters extinguishing fire. Estimation of carbon monoxide quantity absorbed by firefighters was isolated in a group of 40 firefighters from Fire Extinguishing and Rescue Unit of State Fire in Nysa. The study was conducted by measuring carbon monoxide in exhaled air. For measurement of carbon monoxide concentration in exhaled air Micro CO meter was used. Results were demonstrated separately for nonsmokers (n425 and smokers (n415. Mean COHb[%] levels in nonsmokers, measured prior the rescue action was 0,3950,3% and increased statistically significant after the action to 0,6150,34%, while in the group smokers, this level was 2,1750,64% before the action and increased insignificantly after the action to 2,3350,63%. The average COHb level in the same groups before and after exercise, was respectively: for nonsmokers prior to exercise was 0,4850,28% and after exercise decreased statistically significant to 0,3050,27%. In the group of smokers before exercise was 2,2350,61% and decreased statistically significant up to 1,5450,71%. It was no difference between the group of age and time of employment.

  5. LAFD: TA-15 DARHT Firefighter Facility Familiarization Tour, OJT 53044, Revision 0.2

    Energy Technology Data Exchange (ETDEWEB)

    Rutherford, Victor Stephen [Los Alamos National Laboratory; Priestley, Terry B. [Los Alamos National Laboratory; Maestas, Marvin Manuel [Los Alamos National Laboratory

    2016-03-17

    The Los Alamos National Laboratory (LANL or the Lab) will conduct familiarization tours for the Los Alamos County Fire Department (LAFD) at the Dual-Axis Radiographic Hydrodynamic Test (DARHT) Facility, TA-15-0312. The purpose of these tours is to orient LAFD firefighters to the DARHT facility layout and hazards. This document provides information and figures to supplement the familiarization tours. The document will be distributed to the trainees at the time of the familiarization tour. A checklist (Attachment A) has also been developed to ensure that all required information is consistently presented to LAFD personnel during the familiarization tours.

  6. Weight- perception in male career firefighters and its association with cardiovascular risk factors

    Directory of Open Access Journals (Sweden)

    Baur Dorothee M

    2012-06-01

    Full Text Available Abstract Background The prevalence of obesity has reached epidemic proportions worldwide, and is also increasing among public safety professionals like firefighters who are expected to be fit and more active. The present study evaluates the associations among Body Mass Index (BMI, weight perception and cardiovascular risk factors in 768 male career firefighters from two Midwestern states in the United States. Methods A physical examination was performed and fasting blood samples were taken. Cardio-respiratory fitness (CRF was determined from symptom- limited maximal treadmill exercise testing with electrocardiogram (ECG monitoring and estimation of oxygen consumption (metabolic equivalents, METS using the Bruce protocol. A health and lifestyle questionnaire was administered with standardized written instructions for completion. Self-reports of weight perception were extracted from responses to the completed multiple choice questionnaire. Baseline characteristics were described using the mean (standard deviation for continuous variables and frequency for categorical variables. Group comparisons were calculated using analysis of variance (ANOVA. Linear models and logistic regression models were used to adjust for possible confounders. Logistic regression analyses were used to calculate the odds ratios of underestimating one’s weight category. Results A high proportion of overweight and obese male career firefighters underestimate their weight categories (68%. The risk of underestimating one’s weight category increased by 24% with each additional unit of increasing BMI after adjustment for age and CRF. When divided into six groups based on combinations of measured BMI category and weight perception, there were significant differences among the groups for most cardiovascular risk factors. After adjustment for age and BMI, these differences remained statistically significant for CRF, amount of weekly exercise, prevalence of Metabolic Syndrome

  7. Physiological responses and air consumption during simulated firefighting tasks in a subway system.

    Science.gov (United States)

    Williams-Bell, F Michael; Boisseau, Geoff; McGill, John; Kostiuk, Andrew; Hughson, Richard L

    2010-10-01

    Professional firefighters (33 men, 3 women), ranging in age from 30 to 53 years, participated in a simulation of a subway system search and rescue while breathing from their self-contained breathing apparatus (SCBA). We tested the hypothesis that during this task, established by expert firefighters to be of moderate intensity, the rate of air consumption would exceed the capacity of a nominal 30-min cylinder. Oxygen uptake, carbon dioxide output, and air consumption were measured with a portable breath-by-breath gas exchange analysis system, which was fully integrated with the expired port of the SCBA. The task involved descending a flight of stairs, walking, performing a search and rescue, retreat walking, then ascending a single flight of stairs to a safe exit. This scenario required between 9:56 and 13:24 min:s (mean, 12:10 ± 1:10 min:s) to complete, with an average oxygen uptake of 24.3 ± 4.5 mL kg(-1) min(-1) (47 ± 10 % peak oxygen uptake) and heart rate of 76% ± 7% of maximum. The highest energy requirement was during the final single-flight stair climb (30.4 ± 5.4 mL kg(-1) min(-1)). The average respiratory exchange ratio (carbon dioxide output/oxygen uptake) throughout the scenario was 0.95 ± 0.08, indicating a high carbon dioxide output for a relatively moderate average energy requirement. Air consumption from the nominal "30-min" cylinder averaged 51% (range, 26%-68%); however, extrapolation of these rates of consumption suggested that the low-air alarm, signalling that only 25% of the air remains, would have occurred as early as 11 min for an individual with the highest rate of air consumption, and at 16 min for the group average. These data suggest that even the moderate physical demands of walking combined with search and rescue while wearing full protective gear and breathing through the SCBA impose considerable physiological strain on professional firefighters. As well, the rate of air consumption in these tasks classed as moderate, compared

  8. The impact of total sleep deprivation upon cognitive functioning in firefighters

    Directory of Open Access Journals (Sweden)

    Kujawski S

    2018-05-01

    Full Text Available Sławomir Kujawski,1 Joanna Słomko,1 Małgorzata Tafil-Klawe,2 Monika Zawadka-Kunikowska,1 Justyna Szrajda,1 Julia L Newton,3 Paweł Zalewski,1 Jacek J Klawe1 1Department of Hygiene, Epidemiology and Ergonomics, Nicolaus Copernicus University, Toruń, Poland; 2Department of Human Physiology, Nicolaus Copernicus University, Toruń, Poland; 3Institute for Cellular Medicine, Faculty of Medical Sciences, Newcastle University, Framlington Place, Newcastle-upon-Tyne, UK Introduction: Firefighters as a profession are required to maintain high levels of attention for prolonged periods. However, total sleep deprivation (TSD could influence negatively upon performance, particularly when the task is prolonged and repetitive. Purpose: The aim of this study is to examine the influence of TSD on cognitive functioning in a group of firefighters. Subjects and methods: Sixty volunteers who were active male fire brigade officers were examined with a computerized battery test that consisted of simple reaction time (SRT (repeated three times, choice reaction time, visual attention test, and delayed matching to sample. Six series of measurements were undertaken over a period of TSD. Results: Performance in the second attempt in SRT test was significantly worse in terms of increased number of errors and, consequently, decreased number of correct responses during TSD. In contrast, the choice reaction time number of correct responses as well as the visual attention test reaction time for all and correct responses significantly improved compared to initial time points. Conclusion: The study has confirmed that subjects committed significantly more errors and, consequently, noted a smaller number of correct responses in the second attempt of SRT test. However, the remaining results showed reversed direction of TSD influence. TSD potentially leads to worse performance in a relatively easy task in a group of firefighters. Errors during repetitive tasks in firefighting

  9. Three-dimensional carbon network confined antimony nanoparticle anodes for high-capacity K-ion batteries.

    Science.gov (United States)

    Han, Chunhua; Han, Kang; Wang, Xuanpeng; Wang, Chenyang; Li, Qi; Meng, Jiashen; Xu, Xiaoming; He, Qiu; Luo, Wen; Wu, Liming; Mai, Liqiang

    2018-04-19

    Antimony (Sb) represents a promising anode for K-ion batteries (KIBs) due to its high theoretical capacity and suitable working voltage. However, the large volume change that occurs in the potassiation/depotassiation process can lead to severe capacity fading. Herein, we report a high-capacity anode material by in situ confining Sb nanoparticles in a three-dimensional carbon framework (3D SbNPs@C) via a template-assisted freeze-drying treatment and subsequent carbothermic reduction. The as-prepared 3D SbNPs@C hybrid material delivers high reversible capacity and good cycling stability when used as the anode for KIBs. Furthermore, cyclic voltammetry and in situ X-ray diffraction analysis were performed to reveal the intrinsic mechanism of a K-Sb alloying reaction. Therefore, this work is of great importance to understand the electrochemical process of the Sb-based alloying reaction and will pave the way for the exploration of high performance KIB anode materials.

  10. Addition of titanium as a potential catalyst for a high-capacity hydrogen storage medium (abstract only)

    International Nuclear Information System (INIS)

    Zuliani, F; Baerends, E J

    2008-01-01

    In recent years there has been increased interest in the characterization of titanium as a catalyst for high-capacity hydrogen storage materials. A first-principles study (Yildirim and Ciraci 2005 Phys. Rev. Lett. 94 175501) demonstrated that a single Ti atom coated on a single-walled nanotube (SWNT) binds up to four hydrogen molecules. The bonding was claimed to be an 'unusual combination of chemisorption and physisorption'. We report an ab initio study by means of the ADF program, which provides a complete insight into the donation/back-donation mechanism characterizing the bond between the Ti atom and the four H 2 molecules, and a full understanding of the catalytic role played by the Ti atom. In addition, we found that the same amount of adsorbed hydrogen can be stored using benzene support for Ti in place of the SWNT, due to the dominant local contribution of the hexagonal carbon ring surrounding the Ti atom. The benzene-Ti-H 2 bonding is discussed on the basis of molecular orbital interaction schemes as provided by ADF. This result advances our insight into the role of titanium as a catalyst and suggests new routes to better storage through different combinations of supports and catalysts

  11. Manganese Sesquioxide as Cathode Material for Multivalent Zinc Ion Battery with High Capacity and Long Cycle Life

    International Nuclear Information System (INIS)

    Jiang, Baozheng; Xu, Chengjun; Wu, Changle; Dong, Liubing; Li, Jia; Kang, Feiyu

    2017-01-01

    Highlights: • Manganese oxides with Mn(III) state is firstly reported to store zinc ion. • Zinc ion battery with α-Mn 2 O 3 cathode is assembled. • Storage mechanism of zinc ion in α-Mn 2 O 3 is investigated. - Abstract: Rechargeable zinc ion battery is considered as one of the most potential energy storage devices for large-scale energy storage system due to its safety, low-cost, high capacity and nontoxicity. However, only a few cathode materials have been studied for rechargeable zinc ion batteries. Here, we firstly report manganese sesquioxide (Mn 2 O 3 ) with Mn(III) state as cathode material for rechargeable zinc ion battery. The α-Mn 2 O 3 cathode displays a reversible capacity of 148 mAh g −1 , which is relatively high among all the reported cathode materials for ZIB. The cathode also exhibits good rate capability and excellent cycling stability with a long cycle life up to 2000 times. The ion storage mechanism of α-Mn 2 O 3 in zinc ion battery was also revealed. The pristine α-Mn 2 O 3 undergoes a reversible phase transition from bixbyite structure to layered-type zinc birnessite during the electrochemical zinc ion insertion and extraction. The results not only benefit for the practical application of rechargeable zinc ion battery, but also broaden the horizons of understanding the electrochemical behavior and mechanism of rechargeable zinc ion batteries.

  12. Criticality safety and shielding design issues in the development of a high-capacity cask for truck transport

    International Nuclear Information System (INIS)

    Boshoven, J.K.

    1992-01-01

    General Atomics (GA) will be submitting an application for certification to the US Nuclear Regulatory Commission (NRC) for the GA-4 and GA-9 Casks In 1992. The GA-4 and GA-9 Casks are high-capacity legal weight truck casks designed to transport light water reactor spent fuel assemblies. To maintain a capacity of four pressurized-water-reactor (PWR) spent fuel assemblies, the GA-4 Cask uses burnup credit as part of the criticality control for initial enrichments over 3.0 wt% U-235. Using the US Department of Energy (DOE) Burnup Credit Program as a basis, GA has performed burnup credit analysis which is included in the Safety Analysis Report for Packaging (SARP). The GA-9 Cask can meet the criticality safety requirements using the ''fresh fuel'' assumption. Our approach to shielding design is to optimize the GA-4 and GA-9 Cask shielding configurations for minimum weights and maximum payloads. This optimization involves the use of the most effective shielding material, square cross-section geometry with rounded corners and tapered neutron shielding sections in the non-fuel regions

  13. Atomistic Origins of High Capacity and High Structural Stability of Polymer-Derived SiOC Anode Materials.

    Science.gov (United States)

    Sun, Hong; Zhao, Kejie

    2017-10-11

    Capacity and structural stability are often mutually exclusive properties of electrodes in Li-ion batteries (LIBs): a gain in capacity is usually accompanied by the undesired large volumetric change of the host material upon lithiation. Polymer-derived ceramics, such as silicon oxycarbide (SiOC) of hybrid Si-O-C bonds, show an exceptional combination of high capacity and superior structural stability. We investigate the atomistic origins of the unique chemomechanical performance of carbon-rich SiOC using the first-principles theoretical approach. The atomic model of SiOC is composed of continuous Si-O-C units caged by a graphene-like cellular network and percolated nanovoids. The segregated sp 2 carbon network serves as the backbone to maintain the structural stability of the lattice. Li insertion is first absorbed at the nanovoid sites, and then it is accommodated by the SiOC tetrahedral units, excess C atoms, and topological defects at the edge of or within the segregated carbon network. SiOC expands up to 22% in volumetric strain at the fully lithiated capacity of 1230 mA h/g. We examine in great detail the evolution of the microscopic features of the SiOC molecule in the course of Li reactions. The first-principles modeling provides a fundamental understanding of the physicochemical properties of Si-based glass ceramics for their application in LIBs.

  14. Recent advances in high-capacity free-space optical and radio-frequency communications using orbital angular momentum multiplexing

    Science.gov (United States)

    Ren, Yongxiong; Xie, Guodong; Yan, Yan; Li, Long; Zhao, Zhe; Wang, Jian; Tur, Moshe; Molisch, Andreas F.; Ashrafi, Solyman

    2017-01-01

    There is a continuing growth in the demand for data bandwidth, and the multiplexing of multiple independent data streams has the potential to provide the needed data capacity. One technique uses the spatial domain of an electromagnetic (EM) wave, and space division multiplexing (SDM) has become increasingly important for increased transmission capacity and spectral efficiency of a communication system. A subset of SDM is mode division multiplexing (MDM), in which multiple orthogonal beams each on a different mode can be multiplexed. A potential modal basis set to achieve MDM is to use orbital angular momentum (OAM) of EM waves. In such a system, multiple OAM beams each carrying an independent data stream are multiplexed at the transmitter, propagate through a common medium and are demultiplexed at the receiver. As a result, the total capacity and spectral efficiency of the communication system can be multiplied by a factor equal to the number of transmitted OAM modes. Over the past few years, progress has been made in understanding the advantages and limitations of using multiplexed OAM beams for communication systems. In this review paper, we highlight recent advances in the use of OAM multiplexing for high-capacity free-space optical and millimetre-wave communications. We discuss different technical challenges (e.g. atmospheric turbulence and crosstalk) as well as potential techniques to mitigate such degrading effects. This article is part of the themed issue ‘Optical orbital angular momentum’. PMID:28069770

  15. Enabling the high capacity of lithium-rich anti-fluorite lithium iron oxide by simultaneous anionic and cationic redox

    Science.gov (United States)

    Zhan, Chun; Yao, Zhenpeng; Lu, Jun; Ma, Lu; Maroni, Victor A.; Li, Liang; Lee, Eungje; Alp, Esen E.; Wu, Tianpin; Wen, Jianguo; Ren, Yang; Johnson, Christopher; Thackeray, Michael M.; Chan, Maria K. Y.; Wolverton, Chris; Amine, Khalil

    2017-12-01

    Anionic redox reactions in cathodes of lithium-ion batteries are allowing opportunities to double or even triple the energy density. However, it is still challenging to develop a cathode, especially with Earth-abundant elements, that enables anionic redox activity for real-world applications, primarily due to limited strategies to intercept the oxygenates from further irreversible oxidation to O2 gas. Here we report simultaneous iron and oxygen redox activity in a Li-rich anti-fluorite Li5FeO4 electrode. During the removal of the first two Li ions, the oxidation potential of O2- is lowered to approximately 3.5 V versus Li+/Li0, at which potential the cationic oxidation occurs concurrently. These anionic and cationic redox reactions show high reversibility without any obvious O2 gas release. Moreover, this study provides an insightful guide to designing high-capacity cathodes with reversible oxygen redox activity by simply introducing oxygen ions that are exclusively coordinated by Li+.

  16. Systems-level computational modeling demonstrates fuel selection switching in high capacity running and low capacity running rats

    Science.gov (United States)

    Qi, Nathan R.

    2018-01-01

    High capacity and low capacity running rats, HCR and LCR respectively, have been bred to represent two extremes of running endurance and have recently demonstrated disparities in fuel usage during transient aerobic exercise. HCR rats can maintain fatty acid (FA) utilization throughout the course of transient aerobic exercise whereas LCR rats rely predominantly on glucose utilization. We hypothesized that the difference between HCR and LCR fuel utilization could be explained by a difference in mitochondrial density. To test this hypothesis and to investigate mechanisms of fuel selection, we used a constraint-based kinetic analysis of whole-body metabolism to analyze transient exercise data from these rats. Our model analysis used a thermodynamically constrained kinetic framework that accounts for glycolysis, the TCA cycle, and mitochondrial FA transport and oxidation. The model can effectively match the observed relative rates of oxidation of glucose versus FA, as a function of ATP demand. In searching for the minimal differences required to explain metabolic function in HCR versus LCR rats, it was determined that the whole-body metabolic phenotype of LCR, compared to the HCR, could be explained by a ~50% reduction in total mitochondrial activity with an additional 5-fold reduction in mitochondrial FA transport activity. Finally, we postulate that over sustained periods of exercise that LCR can partly overcome the initial deficit in FA catabolic activity by upregulating FA transport and/or oxidation processes. PMID:29474500

  17. Hiding Electronic Patient Record (EPR) in medical images: A high capacity and computationally efficient technique for e-healthcare applications.

    Science.gov (United States)

    Loan, Nazir A; Parah, Shabir A; Sheikh, Javaid A; Akhoon, Jahangir A; Bhat, Ghulam M

    2017-09-01

    A high capacity and semi-reversible data hiding scheme based on Pixel Repetition Method (PRM) and hybrid edge detection for scalable medical images has been proposed in this paper. PRM has been used to scale up the small sized image (seed image) and hybrid edge detection ensures that no important edge information is missed. The scaled up version of seed image has been divided into 2×2 non overlapping blocks. In each block there is one seed pixel whose status decides the number of bits to be embedded in the remaining three pixels of that block. The Electronic Patient Record (EPR)/data have been embedded by using Least Significant and Intermediate Significant Bit Substitution (ISBS). The RC4 encryption has been used to add an additional security layer for embedded EPR/data. The proposed scheme has been tested for various medical and general images and compared with some state of art techniques in the field. The experimental results reveal that the proposed scheme besides being semi-reversible and computationally efficient is capable of handling high payload and as such can be used effectively for electronic healthcare applications. Copyright © 2017. Published by Elsevier Inc.

  18. FDM and DMT performance comparison in high capacity point-to-point fibre links for intra/inter-datacentre connections

    Science.gov (United States)

    Gatto, A.; Parolari, P.; Boffi, P.

    2018-05-01

    Frequency division multiplexing (FDM) is attractive to achieve high capacities in multiple access networks characterized by direct modulation and direct detection. In this paper we take into account point-to-point intra- and inter-datacenter connections to understand the performance of FDM operation compared with the ones achievable with standard multiple carrier modulation approach based on discrete multitone (DMT). DMT and FDM allow to match the non-uniform and bandwidth-limited response of the system under test, associated with the employment of low-cost directly-modulated sources, such as VCSELs with high-frequency chirp, and with fibre-propagation in presence of chromatic dispersion. While for very short distances typical of intra-datacentre communications, the huge number of DMT subcarriers permits to increase the transported capacity with respect to the FDM employment, in case of few tens-km reaches typical of inter-datacentre connections, the capabilities of FDM are more evident, providing system performance similar to the case of DMT application.

  19. Mn 3 O 4 −Graphene Hybrid as a High-Capacity Anode Material for Lithium Ion Batteries

    KAUST Repository

    Wang, Hailiang

    2010-10-13

    We developed two-step solution-phase reactions to form hybrid materials of Mn3O4 nanoparticles on reduced graphene oxide (RGO) sheets for lithium ion battery applications. Selective growth of Mn3O 4 nanoparticles on RGO sheets, in contrast to free particle growth in solution, allowed for the electrically insulating Mn3O4 nanoparticles to be wired up to a current collector through the underlying conducting graphene network. The Mn3O4 nanoparticles formed on RGO show a high specific capacity up to ∼900 mAh/g, near their theoretical capacity, with good rate capability and cycling stability, owing to the intimate interactions between the graphene substrates and the Mn 3O4 nanoparticles grown atop. The Mn3O 4/RGO hybrid could be a promising candidate material for a high-capacity, low-cost, and environmentally friendly anode for lithium ion batteries. Our growth-on-graphene approach should offer a new technique for the design and synthesis of battery electrodes based on highly insulating materials. © 2010 American Chemical Society.

  20. Nanoscale surface modification of Li-rich layered oxides for high-capacity cathodes in Li-ion batteries

    Science.gov (United States)

    Lan, Xiwei; Xin, Yue; Wang, Libin; Hu, Xianluo

    2018-03-01

    Li-rich layered oxides (LLOs) have been developed as a high-capacity cathode material for Li-ion batteries, but the structural complexity and unique initial charging behavior lead to several problems including large initial capacity loss, capacity and voltage fading, poor cyclability, and inferior rate capability. Since the surface conditions are critical to electrochemical performance and the drawbacks, nanoscale surface modification for improving LLO's properties is a general strategy. This review mainly summarizes the surface modification of LLOs and classifies them into three types of surface pre-treatment, surface gradient doping, and surface coating. Surface pre-treatment usually introduces removal of Li2O for lower irreversible capacity while surface doping is aimed to stabilize the structure during electrochemical cycling. Surface coating layers with different properties, protective layers to suppress the interface side reaction, coating layers related to structural transformation, and electronic/ionic conductive layers for better rate capability, can avoid the shortcomings of LLOs. In addition to surface modification for performance enhancement, other strategies can also be investigated to achieve high-performance LLO-based cathode materials.

  1. Changes in permeability of the alveolar-capillary barrier in firefighters.

    Science.gov (United States)

    Minty, B D; Royston, D; Jones, J G; Smith, D J; Searing, C S; Beeley, M

    1985-09-01

    The effect on alveolar-capillary barrier permeability of chronic exposure to a smoke produced by the partial combusion of diesel oil, paraffin, and wood was examined. An index of permeability was determined from the rate of transfer from the lung into the blood of the hydrophilic, labelled chelate 99mTc diethylene triamine penta-acetate (MW 492 dalton). The results of this test were expressed as the half time clearance of the tracer from the lung into the blood (T1/2 LB). The study was carried out at the Royal Naval Firefighting School, HMS Excellent. Permeability index was measured on seven non-smoking naval firefighting instructors who had worked at the school for periods of longer than two and a half months. Tests of airway function and carbon monoxide transfer factor were performed on four of these seven instructors. The results of the permeability index showed a T1/2 LB of 26 min +/- 5 (SEM) which differed significantly from that of normal non-smokers. By contrast all other lung function tests had values within the predicted normal range.

  2. Pain, health perception and sleep: impact on the quality of life of firefighters/rescue professionals

    Directory of Open Access Journals (Sweden)

    Rafael Silva Marconato

    2015-12-01

    Full Text Available Objective: to evaluate the quality of life of firefighters and rescue professionals, and characterize their socio-demographic, health, work and lifestyle profile. Methods: cross-sectional study that used a socio-demographic, lifestyle, health, work data questionnaire and the WHOQOL-BREF quality of life aspects, in Fire Department bases, Civil Air Patrol Group of the Military Police and Rescue Group of Emergency Services. Results: ninety professionals participated in this study - 71 firefighters, 9 nurses, 7 doctors and 3 flight crew members. The average age of the group was 36.4 ± 7.8 years; they worked about 63.7 hours per week; 20.2% reported pain in the last week and 72.7% had body mass index above 25 kg/m2. The average of the WHOQOL-BREF domains was: physical (74.6, psychological (75.2, social (76.5 and environmental (58.7. Significant association was found (Mann-Whitney test and Spearman correlation between the WHOQOL-BREF domains and pain in the past six months, in the last week, health perception, job satisfaction, hours of sleep, domestic tasks and study. Conclusion: the main factors related to quality of life were presence of pain, health perception, sleep and domestic activity.

  3. High-intensity Fitness Training Among a National Sample of Male Career Firefighters

    Directory of Open Access Journals (Sweden)

    Sara A. Jahnke

    2015-03-01

    Full Text Available Obesity and fitness have been identified as key health concerns among USA firefighters yet little is known about the current habits related to exercise and diet. In particular, high-intensity training (HIT has gained increasing popularity among this population but limited quantitative data are available about how often it is used and the relationship between HIT and other outcomes. Using survey methodology, the current study evaluated self-reported HIT and diet practice among 625 male firefighters. Almost one-third (32.3% of participants reported engaging in HIT. Body composition, as measured by waist circumference and percentage body fat, was significantly related to HIT training, with HIT participants being approximately half as likely to be classified as obese using body fat [odds ratio (OR = 0.52, 95% confidence interval (CI = 0.34–0.78] or waist circumference (OR = 0.61, 95% CI = 0.37–0.98. Those who engaged in HIT were more than twice as likely as those who did not (OR = 2.24, 95% CI = 1.42–3.55 to meet fitness recommendations. Findings highlight directions for future prevention and intervention efforts.

  4. A review of heat transfer phenomena and the impact of moisture on firefighters' clothing and protection.

    Science.gov (United States)

    Morel, Aude; Bedek, Gauthier; Salaün, Fabien; Dupont, Daniel

    2014-01-01

    Protective clothing with high insulation properties helps to keep the wearer safe from flames and other types of hazards. Such protection presents some drawbacks since it hinders movement and decreases comfort, in particular due to heat stress. In fact, sweating causes the accumulation of moisture which directly influences firefighters' performance, decreasing protection due to the increase in radiant heat flux. Vaporisation and condensation of hot moisture also induces skin burn. To evaluate the heat protection of protective clothing, Henrique's equation is used to predict the time leading to second-degree burn. The influence of moisture on protection is complex, i.e., at low radiant heat flux, an increase in moisture content increases protection, and also changes thermal properties. Better understanding of heat and mass transfer in protective clothing is required to develop enhanced protection and to prevent burn injuries. This paper aims to contribute to a better understanding of heat and mass transfer inside firefighters' protective clothing to enhance safety. The focus is on the influence of moisture content and the prevention of steam burn.

  5. Comparison of Melatonin Profile and Alertness of Firefighters with Different Work Schedules

    Science.gov (United States)

    Kazemi, Reza; Zare, Sajad

    2018-01-01

    Introduction: A two-shift work schedule with different rotations is common among firefighters in Iranian petrochemical companies. This study compared salivary melatonin and sleepiness on the last night before turning to day shift at 19:00, 23:00, 3:00, and 7:00 among petrochemical firefighters (PFFs) working seven and four consecutive night shifts. Methods: Sixty four PFFs working in the petrochemical industry were selected. To measure melatonin, saliva samples were taken, whereas the KSS index was used to assess sleepiness. Chi-square and independent samples t-test were carried out to analyze the data, and generalized linear model (GLM) was employed to determine the effect of confounding factors such as lighting and caffeine. Results: The levels of melatonin at 3:00 and 7:00, and the overall changes during the shift in the two shift patterns under the study were different (P shift patterns, while the effects of lighting and caffeine on melatonin changes were not significant (P > 0.05). Conclusion: It seems that a slow shift rotation is better because it reduces the secretion of melatonin (hence reducing sleepiness during the night) and changes the peak of melatonin secretion to the daytime, which is a sign of adaptation.

  6. Effect of Air Gap Entrapped in Firefighter Protective Clothing on Thermal Resistance and Evaporative Resistance

    Directory of Open Access Journals (Sweden)

    He Hualing

    2018-03-01

    Full Text Available Heat and water vapor transfer behavior of thermal protective clothing is greatly influenced by the air gap entrapped in multilayer fabric system. In this study, a sweating hot plate method was used to investigate the effect of air gap position and size on thermal resistance and evaporative resistance of firefighter clothing under a range of ambient temperature and humidity. Results indicated that the presence of air gap in multilayer fabric system decreased heat and water vapor transfer abilities under normal wear. Moreover, the air gap position slightly influenced the thermal and evaporative performances of the firefighter clothing. In this study, the multilayer fabric system obtained the highest thermal resistance, when the air space was located at position B. Furthermore, the effect of ambient temperature on heat and water vapor transfer properties of the multilayer fabric system was also investigated in the presence of a specific air gap. It was indicated that ambient temperature did not influence the evaporative resistance of thermal protective clothing. A thermographic image was used to test the surface temperature of multilayer fabric system when an air gap was incorporated. These results suggested that a certain air gap entrapped in thermal protective clothing system could affect wear comfort.

  7. Pain, health perception and sleep: impact on the quality of life of firefighters/rescue professionals.

    Science.gov (United States)

    Marconato, Rafael Silva; Monteiro, Maria Ines

    2015-01-01

    To evaluate the quality of life of firefighters and rescue professionals, and characterize their socio-demographic, health, work and lifestyle profile. Cross-sectional study that used a socio-demographic, lifestyle, health, work data questionnaire and the WHOQOL-BREF quality of life aspects, in Fire Department bases, Civil Air Patrol Group of the Military Police and Rescue Group of Emergency Services. Ninety professionals participated in this study - 71 firefighters, 9 nurses, 7 doctors and 3 flight crew members. The average age of the group was 36.4 ± 7.8 years; they worked about 63.7 hours per week; 20.2% reported pain in the last week and 72.7% had body mass index above 25 kg/m2. The average of the WHOQOL-BREF domains was: physical (74.6), psychological (75.2), social (76.5) and environmental (58.7). Significant association was found (Mann-Whitney test and Spearman correlation) between the WHOQOL-BREF domains and pain in the past six months, in the last week, health perception, job satisfaction, hours of sleep, domestic tasks and study. The main factors related to quality of life were presence of pain, health perception, sleep and domestic activity.

  8. Fire protection at hot laboratories: Prevention, surveillance and fire-fighting

    International Nuclear Information System (INIS)

    Chappellier, A.M.

    1976-01-01

    After pointing out that fire in a hot laboratory can be an important factor contributing to a radioactivity accident, the author briefly recalls the items to be taken into account in a fire hazard analysis. He then describes various important aspects of prevention, detection and fire-fighting which - at the French Commissariat a l'Energie Atomique - are governed by already defined rules or by guidelines which are sufficiently advanced to give a clear idea of the final conclusions to be drawn therefrom. From the point of view protection, the concept of fire sector has been evolved, at hot laboratories, becomes the fire and contamination sector, so as to ensure under all circumstances the containment of any radioactive materials dispersed in the premises on fire. Regarding fire detection, a study should be made on the constraints specific to the facility and liable to affect detector operation. These include ventilation, radiations, neutral or corrosive atmosphere, etc. As regards fire-fighting, two particular aspects are dealt with, namely the question of using water in case of fire and action to be taken concerning ventilation. A practical example - the protection of a ventilation system - is described. In conclusion the paper refers to the need for a thorough analysis specific to each hot laboratory, and to the importance of preparing an operational plan so as to avoid any dangerous improvisations in case of an accident. (author)

  9. The cost and distribution of firefighter injuries in a large Canadian Fire Department.

    Science.gov (United States)

    Frost, D M; Beach, T A C; Crosby, I; McGill, S M

    2016-11-22

    There is limited data available regarding the cost of firefighter injuries. This information is necessary to develop targeted injury prevention strategies. To categorize the cost of injuries filed in 2012 by firefighters from a from a large department by job duty, injury type, body part affected, and the general motion pattern employed at the time of injury. Data were taken from reports filed by CFD personnel and claims filed with the Workers' Compensation Board (WCB) of Alberta between January 1, 2012 and December 31, 2012. Of the 244 injuries reported, 65% were categorized as sprains and strains, the most frequent of which affected the back (32%). The total cost of all claims was $555,955; 77% were sprain/strain-related. Knee and back injuries were most costly ($157,383 and $100,459). Categorized by job duty, most sprains/strains (31%) were sustained while attending to fire station responsibilities, although physical training was associated with the highest costs (34%). Fireground operations were attributed to 18% of sprains/strains and 16% of costs. Lifting injuries were more frequent (23%) and costly (20%) than all injuries. The most common and costly injuries occurred while attending to fire station-related responsibilities and during physical training.

  10. A fractionation of the physiological burden of the personal protective equipment worn by firefighters.

    Science.gov (United States)

    Taylor, Nigel A S; Lewis, Michael C; Notley, Sean R; Peoples, Gregory E

    2012-08-01

    Load carriage increases physiological strain, reduces work capacity and elevates the risk of work-related injury. In this project, the separate and combined physiological consequences of wearing the personal protective equipment used by firefighters were evaluated. The overall impact upon performance was first measured in 20 subjects during a maximal, job-related obstacle course trial and an incremental treadmill test to exhaustion (with and without protective equipment). The fractional contributions of the thermal protective clothing, helmet, breathing apparatus and boots were then separately determined during steady-state walking (4.8 km h(-1), 0% gradient) and bench stepping (20 cm at 40 steps min(-1)). The protective equipment reduced exercise tolerance by 56% on a treadmill, with the ambulatory oxygen consumption reserve (peak minus steady-state walking) being 31% lower. For the obstacle course, performance declined by 27%. Under steady-state conditions, the footwear exerted the greatest relative metabolic impact during walking and bench stepping, being 8.7 and 6.4 times greater per unit mass than the breathing apparatus. Indeed, the relative influence of the clothing on oxygen cost was at least three times that of the breathing apparatus. Therefore, the most efficient way to reduce the physiological burden of firefighters' protective equipment, and thereby increase safety, would be to reduce the mass of the boots and thermal protective clothing.

  11. What Does It Cost to Prevent On-Duty Firefighter Cardiac Events? A Content Valid Method for Calculating Costs

    Directory of Open Access Journals (Sweden)

    P. Daniel Patterson

    2013-01-01

    Full Text Available Cardiac arrest is a leading cause of mortality among firefighters. We sought to develop a valid method for determining the costs of a workplace prevention program for firefighters. In 2012, we developed a draft framework using human resource accounting and in-depth interviews with experts in the firefighting and insurance industries. The interviews produced a draft cost model with 6 components and 26 subcomponents. In 2013, we randomly sampled 100 fire chiefs out of >7,400 affiliated with the International Association of Fire Chiefs. We used the Content Validity Index (CVI to identify the content valid components of the draft cost model. This was accomplished by having fire chiefs rate the relevancy of cost components using a 4-point Likert scale (highly relevant to not relevant. We received complete survey data from 65 fire chiefs (65% response rate. We retained 5 components and 21 subcomponents based on CVI scores ≥0.70. The five main components include, (1 investment costs, (2 orientation and training costs, (3 medical and pharmaceutical costs, (4 education and continuing education costs, and (5 maintenance costs. Data from a diverse sample of fire chiefs has produced a content valid method for calculating the cost of a prevention program among firefighters.

  12. The toxic exposure of flamingos to per- and Polyfluoroalkyl substances (PFAS) from firefighting foam applications in Bonaire.

    NARCIS (Netherlands)

    de Vries, Pepijn; Slijkerman, Diana M E; Kwadijk, Christiaan J A F; Kotterman, Michiel J J; Posthuma, Leo; de Zwart, Dick; Murk, Albertinka J; Foekema, Edwin M

    2017-01-01

    In 2010 an oil terminal next to nature reservation Saliña Goto (Bonaire) caught fire. Firefighting resulted in elevated per- and polyfluoroalkyl substances (PFAS) concentrations in the salt lake. Within months flamingo abundance in Goto dropped to near complete absence. After statistical analysis,

  13. The toxic exposure of flamingos to per - and Polyfluoroalkyl substances (PFAS) from firefighting foam applications in Bonaire

    NARCIS (Netherlands)

    Vries, De Pepijn; Slijkerman, Diana M.E.; Kwadijk, Christiaan J.A.F.; Kotterman, Michael; Posthuma, Leo; Zwart, De Dick; Murk, A.J.; Foekema, Edwin M.

    2017-01-01

    In 2010 an oil terminal next to nature reservation Saliña Goto (Bonaire) caught fire. Firefighting resulted in elevated per- and polyfluoroalkyl substances (PFAS) concentrations in the salt lake. Within months flamingo abundance in Goto dropped to near complete absence. After statistical analysis,

  14. The toxic exposure of flamingos to per- and Polyfluoroalkyl substances (PFAS) from firefighting foam applications in Bonaire

    NARCIS (Netherlands)

    de Vries, P.; Slijkerman, D.M.E.; Kwadijk, C.J.A.F.; Kotterman, M.J.J.; Posthuma, L.; De Zwart, D.; Murk, A.J.; Foekema, E.M.

    2017-01-01

    In 2010 an oil terminal next to nature reservation Saliña Goto (Bonaire) caught fire. Firefighting resulted in elevated per- and polyfluoroalkyl substances (PFAS) concentrations in the salt lake. Within months flamingo abundance in Goto dropped to near complete absence. After statistical analysis,

  15. Skin sites to predict deep-body temperature while wearing firefighters' personal protective equipment during periodical changes in air temperature.

    Science.gov (United States)

    Kim, Siyeon; Lee, Joo-Young

    2016-04-01

    The aim of this study was to investigate stable and valid measurement sites of skin temperatures as a non-invasive variable to predict deep-body temperature while wearing firefighters' personal protective equipment (PPE) during air temperature changes. Eight male firefighters participated in an experiment which consisted of 60-min exercise and 10-min recovery while wearing PPE without self-contained breathing apparatus (7.75 kg in total PPE mass). Air temperature was periodically fluctuated from 29.5 to 35.5 °C with an amplitude of 6 °C. Rectal temperature was chosen as a deep-body temperature, and 12 skin temperatures were recorded. The results showed that the forehead and chest were identified as the most valid sites to predict rectal temperature (R(2) = 0.826 and 0.824, respectively) in an environment with periodically fluctuated air temperatures. This study suggests that particular skin temperatures are valid as a non-invasive variable when predicting rectal temperature of an individual wearing PPE in changing ambient temperatures. Practitioner Summary: This study should offer assistance for developing a more reliable indirect indicating system of individual heat strain for firefighters in real time, which can be used practically as a precaution of firefighters' heat-related illness and utilised along with physiological monitoring.

  16. Nanoelectrospray high capacity ion trap multiple stage mass spectrometry for the structural analysis of human brain gangliosides

    International Nuclear Information System (INIS)

    Vukelic, Zeljka; Ratiu, Cornelia; Grozescu, Ioan; Zamfir, Alina Diana

    2006-01-01

    Full text: A novel protocol based on electrospray ionization (ESI) multiple stage high capacity ion trap (HCT) mass spectrometry (MS) was developed for glycosphingolipidomic surveys. The method was optimized for detailed structural elucidation of human brain gangliosides and particularly applied to human hippocampus-associated structures. The multiple stage MS experiments allowed for a complete structural characterization of GM1 ganglioside species, which was achieved by elucidation of the oligosaccharide sequence, identification of the GM1 a structural isomer from the data upon sialic acid localization along the sugar backbone and determination of the d18:1/18:0 of fatty acid/sphingoid base composition of the ceramide moiety. The methodology developed here is of general practical applicability for glycolipids and represents a step forward in the implementation of the advanced and most modern MS methods in glycomics. Gangliosides are glycosphingolipids, which consist of a mono- to polysialylated oligosaccharide chain of variable length attached to a ceramide portion of different composition with respect to the type of sphingoid base and fatty acid residues. Among all body systems, the central nervous system (CNS) possesses the highest content of gangliosides and they are playing a particularly important biological role at this level. Specific changes in the ganglioside expression and type of the expressed structures were observed to occur during brain development, maturation, and aging, and due to diseases or neurodegeneration processes. Gangliosides represent, therefore, an important class of biomarkers, carriers of information upon various CNS processes and events. Though in the human brain, their expression was observed to have a regional and tissue development induced specificity, the differences in ganglioside structure, composition and quantity were not systematically investigated or rigorously determined so far. (authors)

  17. Stress Dispersed Cu Metal Anode by Laser Multiscale Patterning for Lithium-Ion Batteries with High Capacity

    Directory of Open Access Journals (Sweden)

    Jin-Young So

    2018-06-01

    Full Text Available Electric power production continues to increase as the industry advances, and the demand for high-capacity batteries for efficient operation of the electric power produced is higher than ever before. Si has been attracting a great deal of attention recently as an anode electrode material because of its high theoretical capacity. However, it suffers from significant capacity-loss, resulting from the volume-expansion of Si during charge and discharge cycles. Inspired by the multiscale structures commonly found in nature, we attempt to solve this problem by patterning the surface of the Cu current-collector. To this end, we develop a direct, one-step method using laser patterning to manufacture a multiscale structure on the surface of the current-collector. The inherent exfoliation characteristic of the Cu current-collector allows the spontaneous formation of the multiscale structure while being irradiated with a laser. A micro/nano structure, with a different surface area, is fabricated by varying the laser output at three levels, and the batteries prepared with the fabricated Cu current-collector are tested to evaluate their charge-discharge characteristics and electrochemical impedance. The results show that the multiscale structure reduces mechanical stress. The initial capacity of the Cu current-collector is proportional to the laser output, and the initial capacity of the coin cell prepared with the Cu current-collector, fabricated at the highest laser output, is 396.7% higher than that of the coin cell prepared with a bare Cu current-collector. The impedance is inversely proportional to the laser output. The charge transfer resistance of the coin cell prepared with the Cu current-collector and irradiated with the highest laser output is 190.2% lower than that of the coin cell prepared with the bare Cu current-collector.

  18. Development and evaluation of a low-cost and high-capacity DICOM image data storage system for research.

    Science.gov (United States)

    Yakami, Masahiro; Ishizu, Koichi; Kubo, Takeshi; Okada, Tomohisa; Togashi, Kaori

    2011-04-01

    Thin-slice CT data, useful for clinical diagnosis and research, is now widely available but is typically discarded in many institutions, after a short period of time due to data storage capacity limitations. We designed and built a low-cost high-capacity Digital Imaging and COmmunication in Medicine (DICOM) storage system able to store thin-slice image data for years, using off-the-shelf consumer hardware components, such as a Macintosh computer, a Windows PC, and network-attached storage units. "Ordinary" hierarchical file systems, instead of a centralized data management system such as relational database, were adopted to manage patient DICOM files by arranging them in directories enabling quick and easy access to the DICOM files of each study by following the directory trees with Windows Explorer via study date and patient ID. Software used for this system was open-source OsiriX and additional programs we developed ourselves, both of which were freely available via the Internet. The initial cost of this system was about $3,600 with an incremental storage cost of about $900 per 1 terabyte (TB). This system has been running since 7th Feb 2008 with the data stored increasing at the rate of about 1.3 TB per month. Total data stored was 21.3 TB on 23rd June 2009. The maintenance workload was found to be about 30 to 60 min once every 2 weeks. In conclusion, this newly developed DICOM storage system is useful for research due to its cost-effectiveness, enormous capacity, high scalability, sufficient reliability, and easy data access.

  19. High-Capacity Micrometer-Sized Li 2 S Particles as Cathode Materials for Advanced Rechargeable Lithium-Ion Batteries

    KAUST Repository

    Yang, Yuan

    2012-09-19

    Li 2S is a high-capacity cathode material for lithium metal-free rechargeable batteries. It has a theoretical capacity of 1166 mAh/g, which is nearly 1 order of magnitude higher than traditional metal oxides/phosphates cathodes. However, Li 2S is usually considered to be electrochemically inactive due to its high electronic resistivity and low lithium-ion diffusivity. In this paper, we discover that a large potential barrier (∼1 V) exists at the beginning of charging for Li 2S. By applying a higher voltage cutoff, this barrier can be overcome and Li 2S becomes active. Moreover, this barrier does not appear again in the following cycling. Subsequent cycling shows that the material behaves similar to common sulfur cathodes with high energy efficiency. The initial discharge capacity is greater than 800 mAh/g for even 10 μm Li 2S particles. Moreover, after 10 cycles, the capacity is stabilized around 500-550 mAh/g with a capacity decay rate of only ∼0.25% per cycle. The origin of the initial barrier is found to be the phase nucleation of polysulfides, but the amplitude of barrier is mainly due to two factors: (a) charge transfer directly between Li 2S and electrolyte without polysulfide and (b) lithium-ion diffusion in Li 2S. These results demonstrate a simple and scalable approach to utilizing Li 2S as the cathode material for rechargeable lithium-ion batteries with high specific energy. © 2012 American Chemical Society.

  20. Conductive Boron-Doped Graphene as an Ideal Material for Electrocatalytically Switchable and High-Capacity Hydrogen Storage.

    Science.gov (United States)

    Tan, Xin; Tahini, Hassan A; Smith, Sean C

    2016-12-07

    Electrocatalytic, switchable hydrogen storage promises both tunable kinetics and facile reversibility without the need for specific catalysts. The feasibility of this approach relies on having materials that are easy to synthesize, possessing good electrical conductivities. Graphitic carbon nitride (g-C 4 N 3 ) has been predicted to display charge-responsive binding with molecular hydrogen-the only such conductive sorbent material that has been discovered to date. As yet, however, this conductive variant of graphitic carbon nitride is not readily synthesized by scalable methods. Here, we examine the possibility of conductive and easily synthesized boron-doped graphene nanosheets (B-doped graphene) as sorbent materials for practical applications of electrocatalytically switchable hydrogen storage. Using first-principle calculations, we find that the adsorption energy of H 2 molecules on B-doped graphene can be dramatically enhanced by removing electrons from and thereby positively charging the adsorbent. Thus, by controlling charge injected or depleted from the adsorbent, one can effectively tune the storage/release processes which occur spontaneously without any energy barriers. At full hydrogen coverage, the positively charged BC 5 achieves high storage capacities up to 5.3 wt %. Importantly, B-doped graphene, such as BC 49 , BC 7 , and BC 5 , have good electrical conductivity and can be easily synthesized by scalable methods, which positions this class of material as a very good candidate for charge injection/release. These predictions pave the route for practical implementation of electrocatalytic systems with switchable storage/release capacities that offer high capacity for hydrogen storage.

  1. Fetal muscle gene transfer is not enhanced by an RGD capsid modification to high-capacity adenoviral vectors.

    Science.gov (United States)

    Bilbao, R; Reay, D P; Hughes, T; Biermann, V; Volpers, C; Goldberg, L; Bergelson, J; Kochanek, S; Clemens, P R

    2003-10-01

    High levels of alpha(v) integrin expression by fetal muscle suggested that vector re-targeting to integrins could enhance adenoviral vector-mediated transduction, thereby increasing safety and efficacy of muscle gene transfer in utero. High-capacity adenoviral (HC-Ad) vectors modified by an Arg-Gly-Asp (RGD) peptide motif in the HI loop of the adenoviral fiber (RGD-HC-Ad) have demonstrated efficient gene transfer through binding to alpha(v) integrins. To test integrin targeting of HC-Ad vectors for fetal muscle gene transfer, we compared unmodified and RGD-modified HC-Ad vectors. In vivo, unmodified HC-Ad vector transduced fetal mouse muscle with four-fold higher efficiency compared to RGD-HC-Ad vector. Confirming that the difference was due to muscle cell autonomous factors and not mechanical barriers, transduction of primary myogenic cells isolated from murine fetal muscle in vitro demonstrated a three-fold better transduction by HC-Ad vector than by RGD-HC-Ad vector. We hypothesized that the high expression level of coxsackievirus and adenovirus receptor (CAR), demonstrated in fetal muscle cells both in vitro and in vivo, was the crucial variable influencing the relative transduction efficiencies of HC-Ad and RGD-HC-Ad vectors. To explore this further, we studied transduction by HC-Ad and RGD-HC-Ad vectors in paired cell lines that expressed alpha(v) integrins and differed only by the presence or absence of CAR expression. The results increase our understanding of factors that will be important for retargeting HC-Ad vectors to enhance gene transfer to fetal muscle.

  2. High-capacity lithium-ion battery conversion cathodes based on iron fluoride nanowires and insights into the conversion mechanism.

    Science.gov (United States)

    Li, Linsen; Meng, Fei; Jin, Song

    2012-11-14

    The increasing demands from large-scale energy applications call for the development of lithium-ion battery (LIB) electrode materials with high energy density. Earth abundant conversion cathode material iron trifluoride (FeF(3)) has a high theoretical capacity (712 mAh g(-1)) and the potential to double the energy density of the current cathode material based on lithium cobalt oxide. Such promise has not been fulfilled due to the nonoptimal material properties and poor kinetics of the electrochemical conversion reactions. Here, we report for the first time a high-capacity LIB cathode that is based on networks of FeF(3) nanowires (NWs) made via an inexpensive and scalable synthesis. The FeF(3) NW cathode yielded a discharge capacity as high as 543 mAh g(-1) at the first cycle and retained a capacity of 223 mAh g(-1) after 50 cycles at room temperature under the current of 50 mA g(-1). Moreover, high-resolution transmission electron microscopy revealed the existence of continuous networks of Fe in the lithiated FeF(3) NWs after discharging, which is likely an important factor for the observed improved electrochemical performance. The loss of active material (FeF(3)) caused by the increasingly ineffective reconversion process during charging was found to be a major factor responsible for the capacity loss upon cycling. With the advantages of low cost, large quantity, and ease of processing, these FeF(3) NWs are not only promising battery cathode materials but also provide a convenient platform for fundamental studies and further improving conversion cathodes in general.

  3. Compressed air demand-type firefighter's breathing system, volume 1. [design analysis and performance tests

    Science.gov (United States)

    Sullivan, J. L.

    1975-01-01

    The commercial availability of lightweight high pressure compressed air vessels has resulted in a lightweight firefighter's breathing apparatus. The improved apparatus, and details of its design and development are described. The apparatus includes a compact harness assembly, a backplate mounted pressure reducer assembly, a lightweight bubble-type facemask with a mask mounted demand breathing regulator. Incorporated in the breathing regulator is exhalation valve, a purge valve and a whistle-type low pressure warning that sounds only during inhalation. The pressure reducer assembly includes two pressure reducers, an automatic transfer valve and a signaling device for the low pressure warning. Twenty systems were fabricated, tested, refined through an alternating development and test sequence, and extensively examined in a field evaluation program. Photographs of the apparatus are included.

  4. The Prediction of Training Proficiency in Firefighters: A Study of Predictive Validity in Spain

    Directory of Open Access Journals (Sweden)

    Alfredo Berges

    2018-02-01

    Full Text Available The present study provides results of criterion validity in the selection of firefighters in Spain. The predictors were cognitive skills, job knowledge, and physical aptitudes, and the criterion was training proficiency. The process involves 639 candidates, but only 44 complete successfully the selection process. Our results support previous evidence showing that general cognitive ability is the best predictor of training proficiency, with an operational validity of .57. With respect to the other predictors, job knowledge presented an operational validity of .55 and physical tests of .49. In addition, multiple regression analysis showed that cognitive aptitude explains 33% of the variance, but when physical aptitudes are included the explained variance increases to 50%. If we also add job knowledge, explained variance increases to 55%. Our study offers recent results of criterion validity in a barely investigated job, gathered in a country other than the one where prior research had been carried out.

  5. Variability in performance on a work simulation test of physical fitness for firefighters.

    Science.gov (United States)

    Boyd, Liam; Rogers, Todd; Docherty, David; Petersen, Stewart

    2015-04-01

    The Canadian Forces Firefighter Physical Fitness Maintenance Evaluation (FF PFME) requires firefighters in full fire-protective ensemble, including self-contained breathing apparatus, to correctly complete 10 work-related tasks on a measured and calibrated course. Fitness for duty is inferred from completion time of the course. We hypothesized that completion time may be dependent on pacing strategy and day-to-day fluctuations in biological function. To examine variability in performance, 20 females and 31 males (mean ± SD; age, 27.6 ± 10.5 years; height, 176.7 ± 8.3 cm; mass, 77.3 ± 13.4 kg) were familiarized with the FF PFME and then completed the test on 6 separate days. Pre-test behaviours (e.g., sleep, diet) and test conditions (e.g., calibration, time of day) were consistent. Repeated-measures ANOVA revealed a significant decrease in completion time between tests 1 and 6 (18.7%) and between all sequential pairs (e.g., tests 1 and 2). There was also a small but significant increase in the fraction of total test time for task completion and a corresponding decrease in the time to transition between tasks. The performance improvements cannot be explained by differences in effort (heart rate and perceived exertion). Coefficient of variation for tests 1, 2, and 3 was 7% and for tests 4, 5, and 6 was 2.6%. The results indicate the importance of practice on performance and the potential for false-positive or false-negative decision errors if biological variability is not taken into account.

  6. Multiple Days of Heat Exposure on Firefighters' Work Performance and Physiology.

    Science.gov (United States)

    Larsen, Brianna; Snow, Rod; Vincent, Grace; Tran, Jacqueline; Wolkow, Alexander; Aisbett, Brad

    2015-01-01

    This study assessed the accumulated effect of ambient heat on the performance of, and physiological and perceptual responses to, intermittent, simulated wildfire fighting tasks over three consecutive days. Firefighters (n = 36) were matched and allocated to either the CON (19°C) or HOT (33°C) condition. They performed three days of intermittent, self-paced simulated firefighting work, interspersed with physiological testing. Task repetitions were counted (and converted to distance or area) to determine work performance. Participants were asked to rate their perceived exertion and thermal sensation after each task. Heart rate, core temperature (Tc), and skin temperature (Tsk) were recorded continuously throughout the simulation. Fluids were consumed ad libitum. Urine volume was measured throughout, and urine specific gravity (USG) analysed, to estimate hydration. All food and fluid consumption was recorded. There was no difference in work output between experimental conditions. However, significant variation in performance responses between individuals was observed. All measures of thermal stress were elevated in the HOT, with core and skin temperature reaching, on average, 0.24 ± 0.08°C and 2.81 ± 0.20°C higher than the CON group. Participants' doubled their fluid intake in the HOT condition, and this was reflected in the USG scores, where the HOT participants reported significantly lower values. Heart rate was comparable between conditions at nearly all time points, however the peak heart rate reached each circuit was 7 ± 3% higher in the CON trial. Likewise, RPE was slightly elevated in the CON trial for the majority of tasks. Participants' work output was comparable between the CON and HOT conditions, however the performance change over time varied significantly between individuals. It is likely that the increased fluid replacement in the heat, in concert with frequent rest breaks and task rotation, assisted with the regulation of physiological responses

  7. Multiple Days of Heat Exposure on Firefighters' Work Performance and Physiology.

    Directory of Open Access Journals (Sweden)

    Brianna Larsen

    Full Text Available This study assessed the accumulated effect of ambient heat on the performance of, and physiological and perceptual responses to, intermittent, simulated wildfire fighting tasks over three consecutive days. Firefighters (n = 36 were matched and allocated to either the CON (19°C or HOT (33°C condition. They performed three days of intermittent, self-paced simulated firefighting work, interspersed with physiological testing. Task repetitions were counted (and converted to distance or area to determine work performance. Participants were asked to rate their perceived exertion and thermal sensation after each task. Heart rate, core temperature (Tc, and skin temperature (Tsk were recorded continuously throughout the simulation. Fluids were consumed ad libitum. Urine volume was measured throughout, and urine specific gravity (USG analysed, to estimate hydration. All food and fluid consumption was recorded. There was no difference in work output between experimental conditions. However, significant variation in performance responses between individuals was observed. All measures of thermal stress were elevated in the HOT, with core and skin temperature reaching, on average, 0.24 ± 0.08°C and 2.81 ± 0.20°C higher than the CON group. Participants' doubled their fluid intake in the HOT condition, and this was reflected in the USG scores, where the HOT participants reported significantly lower values. Heart rate was comparable between conditions at nearly all time points, however the peak heart rate reached each circuit was 7 ± 3% higher in the CON trial. Likewise, RPE was slightly elevated in the CON trial for the majority of tasks. Participants' work output was comparable between the CON and HOT conditions, however the performance change over time varied significantly between individuals. It is likely that the increased fluid replacement in the heat, in concert with frequent rest breaks and task rotation, assisted with the regulation of

  8. The impact of the World Trade Center attack on FDNY firefighter retirement, disabilities, and pension benefits.

    Science.gov (United States)

    Niles, J K; Webber, M P; Gustave, J; Zeig-Owens, R; Lee, R; Glass, L; Weiden, M D; Kelly, K J; Prezant, D J

    2011-09-01

    Our goal was to examine the effect of the World Trade Center (WTC) attack and subsequent New York City Fire Department (FDNY) rescue/recovery activities on firefighter retirements. We also analyzed the financial impact associated with the increased number and proportion of service-connected "accidental" disability retirements on the FDNY pension system. A total of 7,763 firefighters retired between 9/11/1994 and 9/10/2008. We compared the total number of retirements and the number and proportion of accidental disability retirements 7 years before and 7 years after the WTC attack. We categorized WTC-related accidental disability retirements by medical cause and worked with the New York City Office of the Actuary to approximate the financial impact by cause. In the 7 years before 9/11 there were 3,261 retirements, 48% (1,571) of which were accidental disability retirements. In the 7 years after 9/11, there were 4,502 retirements, 66% (2,970) were accidental disability retirements, of which 47% (1,402) were associated with WTC-related injuries or illnesses. After 9/11, the increase in accidental disability retirements was, for the most part, due to respiratory-related illnesses. Additional increases were attributed to psychological-related illnesses and musculoskeletal injuries incurred at the WTC site. Pension benefits associated with WTC-related accidental disability retirements have produced an increased financial burden of over $826 million on the FDNY pension system. The WTC attacks affected the health of the FDNY workforce resulting in more post-9/11 retirements than expected, and a larger proportion of these retirees with accidental disability pensions. Copyright © 2011 Wiley-Liss, Inc.

  9. Low Cost, High Capacity Regenerable Sorbent for Carbon Dioxide Capture from Existing Coal-fired Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Alptekin, Gokhan [TDA Research, Inc., Wheat Ridge, CO (United States); Jayaraman, Ambalavanan [TDA Research, Inc., Wheat Ridge, CO (United States); Dietz, Steven [TDA Research, Inc., Wheat Ridge, CO (United States)

    2016-03-03

    In this project TDA Research, Inc (TDA) has developed a new post combustion carbon capture technology based on a vacuum swing adsorption system that uses a steam purge and demonstrated its technical feasibility and economic viability in laboratory-scale tests and tests in actual coal derived flue gas. TDA uses an advanced physical adsorbent to selectively remove CO2 from the flue gas. The sorbent exhibits a much higher affinity for CO2 than N2, H2O or O2, enabling effective CO2 separation from the flue gas. We also carried out a detailed process design and analysis of the new system as part of both sub-critical and super-critical pulverized coal fired power plants. The new technology uses a low cost, high capacity adsorbent that selectively removes CO2 in the presence of moisture at the flue gas temperature without a need for significant cooling of the flue gas or moisture removal. The sorbent is based on a TDA proprietary mesoporous carbon that consists of surface functionalized groups that remove CO2 via physical adsorption. The high surface area and favorable porosity of the sorbent also provides a unique platform to introduce additional functionality, such as active groups to remove trace metals (e.g., Hg, As). In collaboration with the Advanced Power and Energy Program of the University of California, Irvine (UCI), TDA developed system simulation models using Aspen PlusTM simulation software to assess the economic viability of TDA’s VSA-based post-combustion carbon capture technology. The levelized cost of electricity including the TS&M costs for CO2 is calculated as $116.71/MWh and $113.76/MWh for TDA system integrated with sub-critical and super-critical pulverized coal fired power plants; much lower than the $153.03/MWhand $147.44/MWh calculated for the corresponding amine based systems. The cost of CO2 captured for TDA’s VSA based system is $38

  10. Cobalt Oxide Porous Nanofibers Directly Grown on Conductive Substrate as a Binder/Additive-Free Lithium-Ion Battery Anode with High Capacity.

    Science.gov (United States)

    Liu, Hao; Zheng, Zheng; Chen, Bochao; Liao, Libing; Wang, Xina

    2017-12-01

    In order to reduce the amount of inactive materials, such as binders and carbon additives in battery electrode, porous cobalt monoxide nanofibers were directly grown on conductive substrate as a binder/additive-free lithium-ion battery anode. This electrode exhibited very high specific discharging/charging capacities at various rates and good cycling stability. It was promising as high capacity anode materials for lithium-ion battery.

  11. The Effects of Simulated Wildland Firefighting Tasks on Core Temperature and Cognitive Function under Very Hot Conditions

    Directory of Open Access Journals (Sweden)

    F. Michael Williams-Bell

    2017-10-01

    Full Text Available Background: The severity of wildland fires is increasing due to continually hotter and drier summers. Firefighters are required to make life altering decisions on the fireground, which requires analytical thinking, problem solving, and situational awareness. This study aimed to determine the effects of very hot (45°C; HOT conditions on cognitive function following periods of simulated wildfire suppression work when compared to a temperate environment (18°C; CON.Methods: Ten male volunteer firefighters intermittently performed a simulated fireground task for 3 h in both the CON and HOT environments, with cognitive function tests (paired associates learning and spatial span assessed at baseline (cog 1 and during the final 20-min of each hour (cog 2, 3, and 4. Reaction time was also assessed at cog 1 and cog 4. Pre- and post- body mass were recorded, and core and skin temperature were measured continuously throughout the protocol.Results: There were no differences between the CON and HOT trials for any of the cognitive assessments, regardless of complexity. While core temperature reached 38.7°C in the HOT (compared to only 37.5°C in the CON; p < 0.01, core temperature declined during the cognitive assessments in both conditions (at a rate of −0.15 ± 0.20°C·hr−1 and −0.63 ± 0.12°C·hr−1 in the HOT and CON trial respectively. Firefighters also maintained their pre-exercise body mass in both conditions, indicating euhydration.Conclusions: It is likely that this maintenance of euhydration and the relative drop in core temperature experienced between physical work bouts was responsible for the preservation of firefighters' cognitive function in the present study.

  12. Hearing effects from intermittent and continuous noise exposure in a study of Korean factory workers and firefighters

    Directory of Open Access Journals (Sweden)

    Chung In-Sung

    2012-01-01

    Full Text Available Abstract Background South Korea and surrounding countries in East Asia are believed to have the highest proportion in the world of high frequency hearing loss due to occupational noise exposure, yet there has been limited information published in international journals, and limited information for control of noise in local workplaces beyond strategies from western countries. We exploit medical surveillance information from two worker groups to enhance local knowledge about noise-induced hearing loss and explore the possible importance of shift work to risk. Methods Four-years of hearing data were evaluated for 81 male farm machine factory workers and 371 male firefighters who had successfully completed a health examination and questionnaires for the duration of the study period. The averages of hearing thresholds at 2, 3, and 4 kHz were used as the primary end-point for comparison. Repeat measure analysis adjusted for age, exposure duration and smoking status was used to measure the difference in hearing threshold between the two groups. Results Noise levels were measured in the factory at a mean of 82 dBA, with a range of 66-97. No concurrent measurements were taken for the firefighters, but historic comparison values showed a wider range but a similar mean of 76-79 dBA. Although losses during follow-up were negligible, the factory workers had significantly (P 25 dB loss. Firefighters also showed increased losses associated with longer exposure duration, but these were significantly less marked. Losses at lower frequencies ( Conclusions Korean work environments with continuous noise exposure in the measured range should consider implementation of a hearing conservation program. Further evaluation of hearing loss in workers exposed to irregular or intermittent high noise levels, such as firefighters, is also warranted.

  13. Exercise and cancer: return to work as a firefighter with ostomy after rectal carcinoma - a case report.

    Science.gov (United States)

    Wiskemann, Joachim; Schommer, Kai; Jaeger, Dirk; Scharhag-Rosenberger, Friederike

    2016-07-01

    Colorectal cancer survivors are deconditioned through anticancer therapy. Furthermore, about 10% of them have a permanent ostomy which is associated with weakened abdominal muscles and an increased risk of a hernia. This case study reports on how a firefighter with rectal carcinoma and ostomy was trained to regain operational fitness. A 44-year-old firefighter (178 cm, 82 kg) with an adenocarcinoma of the rectum (diagnosed 24 months prior) had been treated with neoadjuvant radiochemotherapy and surgery. After 2 temporary ileostomies, a permanent colostomy was performed 14 weeks before the start of a 9-months training program. The program included sensorimotor, endurance, and strength training of increasing volume and intensity. Endurance, strength, and patient reported outcomes were assessed every 2 to 3 months. Training frequency varied from 1 to 3 sessions/week, although 3 to 5 sessions/week were prescribed. Peak power output was 150, 158, 167, 192, and 175 watts at baseline, 2, 4, 6, and 9 months. Maximal oxygen uptake increased from 1.56 L/min (19.0 mL/min/kg) to 2.39 L/min (28.8 mL/min/kg) after 6 months. Maximal isokinetic peak torque (MIPT) of the knee extensors were 138.0 and 196.5 Nm (Newton meter) at baseline and 6 months. MIPT of the elbow and hip flexors increased from 51.8 to 66.0 Nm and 213.8 to 239.7 Nm, respectively, after 6 months. Physical fatigue decreased by 65% and distress by about 50% after 9 months. The firefighter passed a test for occupational fitness after 6 months and was permitted to work with an exterior crew on a pump truck. It is possible for colorectal cancer survivors with ostomy to regain occupational fitness for physically demanding tasks like firefighting through an individually tailored and supervised training program.

  14. Summary of efficiency testing of standard and high-capacity high-efficiency particulate air filters subjected to simulated tornado depressurization and explosive shock waves

    International Nuclear Information System (INIS)

    Smith, P.R.; Gregory, W.S.

    1985-04-01

    Pressure transients in nuclear facility air cleaning systems can originate from natural phenomena such as tornadoes or from accident-induced explosive blast waves. This study was concerned with the effective efficiency of high-efficiency particulate air (HEPA) filters during pressure surges resulting from simulated tornado and explosion transients. The primary objective of the study was to examine filter efficiencies at pressure levels below the point of structural failure. Both standard and high-capacity 0.61-m by 0.61-m HEPA filters were evaluated, as were several 0.2-m by 0.2-m HEPA filters. For a particular manufacturer, the material release when subjected to tornado transients is the same (per unit area) for both the 0.2-m by 0.2-m and the 0.61-m by 0.61-m filters. For tornado transients, the material release was on the order of micrograms per square meter. When subjecting clean HEPA filters to simulated tornado transients with aerosol entrained in the pressure pulse, all filters tested showed a degradation of filter efficiency. For explosive transients, the material release from preloaded high-capacity filters was as much as 340 g. When preloaded high-capacity filters were subjected to shock waves approximately 50% of the structural limit level, 1 to 2 mg of particulate was released

  15. The impact of different types of textile liners used in protective footwear on the subjective sensations of firefighters.

    Science.gov (United States)

    Irzmańska, Emilia

    2015-03-01

    The paper presents ergonomic evaluation of footwear used with three types of textile liners differing in terms of design and material composition. Two novel textile composite liners with enhanced hygienic properties were compared with a standard liner used in firefighter boots. The study involved 45 healthy firefighters from fire and rescue units who wore protective footwear with one of the three types of liners. The study was conducted in a laboratory under a normal atmosphere. The ergonomic properties of the protective footwear and liners were evaluated according to the standard EN ISO 20344:2012 as well as using an additional questionnaire concerning the thermal and moisture sensations experienced while wearing the footwear. The study was conducted on a much larger group of subjects (45) than that required by the ISO standard (3) to increase the reliability of subjective evaluations. Some statistically significant differences were found between the different types of textile liners used in firefighter boots. It was confirmed that the ergonomic properties of protective footwear worn in the workplace may be improved by the use of appropriate textile components. Copyright © 2014 Elsevier Ltd and The Ergonomics Society. All rights reserved.

  16. The Effect of Various Hot Environments on Physiological Responses and Information Processing Performance Following Firefighting Activities in a Smoke-Diving Room.

    Science.gov (United States)

    Hemmatjo, Rasoul; Motamedzade, Majid; Aliabadi, Mohsen; Kalatpour, Omid; Farhadian, Maryam

    2017-12-01

    Fire service workers often implement multiple duties in the emergency conditions, with such duties being mostly conducted in various ambient temperatures. The aim of the current study was to assess the firefighters' physiological responses, information processing, and working memory prior to and following simulated firefighting activities in three different hot environments. Seventeen healthy male firefighters performed simulated firefighting tasks in three separate conditions, namely (1) low heat (LH; 29-31°C, 55-60% relative humidity), (2) moderate heat (MH; 32-34°C, 55-60% relative humidity), and (3) severe heat (SH; 35-37°C, 55-60% relative humidity). It took about 45-50 minutes for each firefighter to finish all defined firefighting activities and the paced auditory serial addition test (PASAT). At the end of all the three experimental conditions, heart rate (HR) and tympanic temperature (TT) increased, while PASAT scores as a measure of information processing performance decreased relative to baseline. HR and TT were significantly higher at the end of the experiment in the SH (159.41 ± 4.25 beats/min; 38.22 ± 0.10°C) compared with the MH (156.59 ± 3.77 beats/min; 38.20 ± 0.10°C) and LH (154.24 ± 4.67 beats/min; 38.17 ± 0.10°C) conditions ( p   0.05). Nonetheless, there was a measurable difference in PASAT scores between LH and SH ( p  information processing and working memory during firefighting activity.

  17. The impact of fire suppression tasks on firefighter hydration: a critical review with consideration of the utility of reported hydration measures.

    Science.gov (United States)

    Walker, Adam; Pope, Rodney; Orr, Robin Marc

    2016-01-01

    Firefighting is a highly stressful occupation with unique physical challenges, apparel and environments that increase the potential for dehydration. Dehydration leaves the firefighter at risk of harm to their health, safety and performance. The purpose of this review was to critically analyse the current literature investigating the impact of fighting 'live' fires on firefighter hydration. A systematic search was performed of four electronic databases for relevant published studies investigating the impact of live fire suppression on firefighter hydration. Study eligibility was assessed using strict inclusion and exclusion criteria. The included studies were critically appraised using the Downs and Black protocol and graded according to the Kennelly grading system. Ten studies met the eligibility criteria for this review. The average score for methodological quality was 55 %, ranging from 50 % ('fair' quality) to 61 % ('good' quality) with a 'substantial agreement' between raters ( k  = .772). Wildfire suppression was considered in five studies and structural fire suppression in five studies. Results varied across the studies, reflecting variations in outcome measures, hydration protocols and interventions. Three studies reported significant indicators of dehydration resulting from structural fire suppression, while two studies found mixed results, with some measures indicating dehydration and other measures an unchanged hydration status. Three studies found non-significant changes in hydration resulting from wildfire firefighting and two studies found significant improvements in markers of hydration. Ad libitum fluid intake was a common factor across the studies finding no, or less severe, dehydration. The evidence confirms that structural and wildfire firefighting can cause dehydration. Ad libitum drinking may be sufficient to maintain hydration in many wildfire environments but possibly not during intense, longer duration, hot structural fire operations

  18. The European, Japanese and US protective helmet, gloves and boots for firefighters: thermoregulatory and psychological evaluations.

    Science.gov (United States)

    Lee, Joo-Young; Yamamoto, Yota; Oe, Riichi; Son, Su-Young; Wakabayashi, Hitoshi; Tochihara, Yutaka

    2014-01-01

    The purpose of this study was to investigate the physiological and subjective responses of the European, Japanese (JPN) and US firefighters' helmet, gloves and boots for international standardisation. Three experimental conditions were evaluated (clothing mass: 9.4, 8.2 and 10.1 kg for the three conditions, respectively) at the air temperature of 32°C and 60% relative humidity. The results showed that there was no significant difference among the three conditions in oxygen consumption, heart rate, total sweat rate, rectal temperature and mean skin temperature, whereas peripheral temperatures and subjective perceptions were lower in the JPN condition than in the other conditions (P < 0.05). These results indicate that a 0.5-kg reduction in helmet mass and a 1.1-kg reduction in boot mass during exercise resulted in a significant decrease in head and leg temperatures and subjective perceptions, while a 1.9-kg reduction in total clothing mass had insignificant influences on the metabolic burden and overall body temperature.

  19. Superposed Redox Chemistry of Fused Carbon Rings in Cyclooctatetraene-Based Organic Molecules for High-Voltage and High-Capacity Cathodes.

    Science.gov (United States)

    Zhao, Xiaolin; Qiu, Wujie; Ma, Chao; Zhao, Yingqin; Wang, Kaixue; Zhang, Wenqing; Kang, Litao; Liu, Jianjun

    2018-01-24

    Even though many organic cathodes have been developed and have made a significant improvement in energy density and reversibility, some organic materials always generate relatively low voltage and limited discharge capacity because their energy storage mechanism is solely based on redox reactions of limited functional groups [N-O, C═X (X = O, N, S)] linking to aromatic rings. Here, a series of cyclooctatetraene-based (C 8 H 8 ) organic molecules were demonstrated to have electrochemical activity of high-capacity and high-voltage from carbon rings by means of first-principles calculations and electronic structure analysis. Fused molecules of C 8 -C 4 -C 8 (C 16 H 12 ) and C 8 -C 4 -C 8 -C 4 -C 8 (C 24 H 16 ) contain, respectively, four and eight electron-deficient carbons, generating high-capacity by their multiple redox reactions. Our sodiation calculations predict that C 16 H 12 and C 24 H 16 exhibit discharge capacities of 525.3 and 357.2 mA h g -1 at the voltage change from 3.5 to 1.0 V and 3.7 to 1.3 V versus Na + /Na, respectively. Electronic structure analysis reveals that the high voltages are attributed to superposed electron stabilization mechanisms, including double-bond reformation and aromatization from carbon rings. High thermodynamic stability of these C 24 H 16 -based systems strongly suggests feasibility of experimental realization. The present work provides evidence that cyclooctatetraene-based organic molecules fused with the C 4 ring are promising in designing high-capacity and high-voltage organic rechargeable cathodes.

  20. Increased productivity in construction of civil and mining tunnels through the use of high-capacity tunnel-boring machines and continuous belt conveyor muck haulage

    Energy Technology Data Exchange (ETDEWEB)

    Beatty, J.G.; Ganey, R.J.; Killingsworth, J.E. [Perini Corp., Chicago, IL (United States). US Heavy Division

    1994-12-31

    The use of a large diameter high production tunnel boring machine interfaced with a high capacity continuous belt conveyor system provides a highly productive and cost effective construction system for both civil and mining tunnels. Continuous advance of the tunnel boring machine for a distance of 1,000 feet (305 m) allows for very efficient operation of the system. The available cost reductions will likely prove that this approach to waste handling will make marginally viable projects economically feasible. 9 refs., 10 figs., 1 tab.

  1. Bead Injection Extraction Chromatography using High-capacity Lab-on-Valve as a Front End to Inductively Coupled Plasma Mass Spectrometry for Rapid Urine Radiobioassay

    DEFF Research Database (Denmark)

    Qiao, Jixin; Hou, Xiaolin; Roos, Per

    2013-01-01

    A novel bead injection (BI) extraction chromatographic microflow system exploiting high-capacity lab-on-valve (LOV) platform coupled with inductively coupled plasma mass spectrometric detection is developed for rapid and automated determination of plutonium in human urine. A microconduit (1 m......L) incorporated within the LOV processing unit is loaded on-line with a metered amount of disposable extraction chromatographic resin (up to 330 mg of TEVA) through programmable beads transport. Selective capture and purification of plutonium onto the resin beads is then performed by pressure driven flow after...

  2. Role of H2O2 on the kinetics of low-affinity high-capacity Na+-dependent alanine transport in SHR proximal tubular epithelial cells

    International Nuclear Information System (INIS)

    Pinto, Vanda; Pinho, Maria Joao; Jose, Pedro A.; Soares-da-Silva, Patricio

    2010-01-01

    Research highlights: → H 2 O 2 in excess is required for the presence of a low-affinity high-capacity component for the Na + -dependent [ 14 C]-L-alanine uptake in SHR PTE cells only. → It is suggested that Na + binding in renal ASCT2 may be regulated by ROS in SHR PTE cells. -- Abstract: The presence of high and low sodium affinity states for the Na + -dependent [ 14 C]-L-alanine uptake in immortalized renal proximal tubular epithelial (PTE) cells was previously reported (Am. J. Physiol. 293 (2007) R538-R547). This study evaluated the role of H 2 O 2 on the Na + -dependent [ 14 C]-L-alanine uptake of ASCT2 in immortalized renal PTE cells from Wistar Kyoto rat (WKY) and spontaneously hypertensive rat (SHR). Na + dependence of [ 14 C]-L-alanine uptake was investigated replacing NaCl with an equimolar concentration of choline chloride in vehicle- and apocynin-treated cells. Na + removal from the uptake solution abolished transport activity in both WKY and SHR PTE cells. Decreases in H 2 O 2 levels in the extracellular medium significantly reduced Na + -K m and V max values of the low-affinity high-capacity component in SHR PTE cells, with no effect on the high-affinity low-capacity state of the Na + -dependent [ 14 C]-L-alanine uptake. After removal of apocynin from the culture medium, H 2 O 2 levels returned to basal values within 1 to 3 h in both WKY and SHR PTE cells and these were found stable for the next 24 h. Under these experimental conditions, the Na + -K m and V max of the high-affinity low-capacity state were unaffected and the low-affinity high-capacity component remained significantly decreased 1 day but not 4 days after apocynin removal. In conclusion, H 2 O 2 in excess is required for the presence of a low-affinity high-capacity component for the Na + -dependent [ 14 C]-L-alanine uptake in SHR PTE cells only. It is suggested that Na + binding in renal ASCT2 may be regulated by ROS in SHR PTE cells.

  3. The H{sub 60}Si{sub 6}C{sub 54} heterofullerene as high-capacity hydrogen storage medium

    Energy Technology Data Exchange (ETDEWEB)

    Yong, Yongliang, E-mail: ylyong@haust.edu.cn [College of Physics and Engineering, Henan University of Science and Technology, Luoyang 471003 (China); Department of Physics, Zhejiang University, Hangzhou 310027 (China); Zhou, Qingxiao; Li, Xiaohong; Lv, Shijie [College of Physics and Engineering, Henan University of Science and Technology, Luoyang 471003 (China)

    2016-07-15

    With the great success in Si atoms doped C{sub 60} fullerene and the well-established methods for synthesis of hydrogenated carbon fullerenes, this leads naturally to wonder whether Si-doped fullerenes are possible for special applications such as hydrogen storage. Here by using first-principles calculations, we design a novel high-capacity hydrogen storage material, H{sub 60}Si{sub 6}C{sub 54} heterofullerene, and confirm its geometric stability. It is found that the H{sub 60}Si{sub 6}C{sub 54} heterofullerene has a large HOMO-LUMO gap and a high symmetry, indicating it is high chemically stable. Further, our finite temperature simulations indicate that the H{sub 60}Si{sub 6}C{sub 54} heterofullerene is thermally stable at 300 K. H{sub 2} molecules would enter into the cage from the Si-hexagon ring because of lower energy barrier. Through our calculation, a maximum of 21 H{sub 2} molecules can be stored inside the H{sub 60}Si{sub 6}C{sub 54} cage in molecular form, leading to a gravimetric density of 11.11 wt% for 21H{sub 2}@H{sub 60}Si{sub 6}C{sub 54} system, which suggests that the hydrogenated Si{sub 6}C{sub 54} heterofullerene could be suitable as a high-capacity hydrogen storage material.

  4. Electrostatic Self-Assembly of Fe3O4 Nanoparticles on Graphene Oxides for High Capacity Lithium-Ion Battery Anodes

    Directory of Open Access Journals (Sweden)

    Jung Kyoo Lee

    2013-09-01

    Full Text Available Magnetite, Fe3O4, is a promising anode material for lithium ion batteries due to its high theoretical capacity (924 mA h g−1, high density, low cost and low toxicity. However, its application as high capacity anodes is still hampered by poor cycling performance. To stabilize the cycling performance of Fe3O4 nanoparticles, composites comprising Fe3O4 nanoparticles and graphene sheets (GS were fabricated. The Fe3O4/GS composite disks of mm dimensions were prepared by electrostatic self-assembly between negatively charged graphene oxide (GO sheets and positively charged Fe3O4-APTMS [Fe3O4 grafted with (3-aminopropyltrimethoxysilane (APTMS] in an acidic solution (pH = 2 followed by in situ chemical reduction. Thus prepared Fe3O4/GS composite showed an excellent rate capability as well as much enhanced cycling stability compared with Fe3O4 electrode. The superior electrochemical responses of Fe3O4/GS composite disks assure the advantages of: (1 electrostatic self-assembly between high storage-capacity materials with GO; and (2 incorporation of GS in the Fe3O4/GS composite for high capacity lithium-ion battery application.

  5. Exposure–response relationships for select cancer and non-cancer health outcomes in a cohort of US firefighters from San Francisco, Chicago and Philadelphia (1950–2009)

    Science.gov (United States)

    Daniels, Robert D.; Bertke, Stephen; Dahm, Matthew M.; Yiin, James H.; Kubale, Travis L.; Hales, Thomas R.; Baris, Dalsu; Zahm, Shelia H.; Beaumont, James J.; Waters, Kathleen M.; Pinkerton, Lynne E.

    2015-01-01

    Objectives To examine exposure–response relationships between surrogates of firefighting exposure and select outcomes among previously studied US career firefighters. Methods Eight cancer and four non-cancer outcomes were examined using conditional logistic regression. Incidence density sampling was used to match each case to 200 controls on attained age. Days accrued in firefighting assignments (exposed-days), run totals (fire-runs) and run times (fire-hours) were used as exposure surrogates. HRs comparing 75th and 25th centiles of lagged cumulative exposures were calculated using loglinear, linear, log-quadratic, power and restricted cubic spline general relative risk models. Piecewise constant models were used to examine risk differences by time since exposure, age at exposure and calendar period. Results Among 19 309 male firefighters eligible for the study, there were 1333 cancer deaths and 2609 cancer incidence cases. Significant positive associations between fire-hours and lung cancer mortality and incidence were evident. A similar relation between leukaemia mortality and fire-runs was also found. The lung cancer associations were nearly linear in cumulative exposure, while the association with leukaemia mortality was attenuated at higher exposure levels and greater for recent exposures. Significant negative associations were evident for the exposure surrogates and colorectal and prostate cancers, suggesting a healthy worker survivor effect possibly enhanced by medical screening. Conclusions Lung cancer and leukaemia mortality risks were modestly increasing with firefighter exposures. These findings add to evidence of a causal association between firefighting and cancer. Nevertheless, small effects merit cautious interpretation. We plan to continue to follow the occurrence of disease and injury in this cohort. PMID:25673342

  6. Examining anxiety sensitivity as a mediator of the association between PTSD symptoms and suicide risk among women firefighters.

    Science.gov (United States)

    Stanley, Ian H; Hom, Melanie A; Spencer-Thomas, Sally; Joiner, Thomas E

    2017-08-01

    Posttraumatic stress disorder (PTSD) symptoms are associated with increased suicide risk. Anxiety sensitivity (AS)-the fear of anxiety-related sensations-is both a vulnerability factor for and consequence of PTSD symptoms. AS also predicts suicide risk. To our knowledge, no study has examined whether AS concerns account for the association between PTSD symptoms and suicide risk. A total of 254 women firefighters completed a web-based mental health survey. The Life Events Checklist for DSM-5 (LEC-5) was administered as a prelude to the PTSD Checklist for DSM-5 (PCL-5) to assess for exposure to a Criterion A event. The PCL-5, Anxiety Sensitivity Index-3 (ASI-3), and Suicidal Behaviors Questionnaire-Revised (SBQ-R) were utilized to assess PTSD symptoms, AS concerns, and suicide risk, respectively. Bootstrap mediation analyses were conducted, controlling for depression symptoms as measured by the Center for Epidemiologic Studies Depression Scale-Revised (CESD-R). Global and cognitive AS concerns, but neither physical nor social AS concerns, were statistically significant mediators of the relationship between PTSD symptoms (total score, re-experiencing and numbing clusters) and suicide risk. Alternate mediation models testing PTSD symptoms as a mediator of the relationship between AS concerns and suicide risk were not statistically significant, supporting the specificity of our proposed model. Anxiety sensitivity concerns-specifically, cognitive AS concerns-account for the link between PTSD symptoms and suicide risk among women firefighters. Among firefighters with elevated PTSD symptoms, interventions that address cognitive AS concerns may thwart the trajectory to suicidal thoughts and behaviors. Copyright © 2017 Elsevier Ltd. All rights reserved.

  7. Responding to Terrorist Incidents in Your Community: Flammable-Liquid Fire Fighting Techniques for Municipal and Rural Firefighters

    Energy Technology Data Exchange (ETDEWEB)

    Denise Baclawski

    2010-03-08

    The University of Nevada, Reno Fire Science Academy (FSA) applied for grant funding to develop and deliver programs for municipal, rural, and volunteer firefighters. The FSA specializes in preparing responders for a variety of emergency events, including flammable liquid fires resulting from accidents, intentional acts, or natural disasters. Live fire training on full scale burnable props is the hallmark of FSA training, allowing responders to practice critical skills in a realistic, yet safe environment. Unfortunately, flammable liquid live fire training is often not accessible to municipal, rural, or volunteer firefighters due to limited department training budgets, even though most department personnel will be exposed to flammable liquid fire incidents during the course of their careers. In response to this training need, the FSA developed a course during the first year of the grant (Year One), Responding to Terrorist Incidents in Your Community: Flammable-Liquid Fire Fighting Techniques for Municipal and Rural Firefighters. During the three years of the grant, a total of 2,029 emergency responders received this training. In Year Three, two new courses, a train-the-trainer for Responding to Terrorist Incidents in Your Community and Management of Large-Scale Disasters for Public Officials were developed and pilot tested during the Real-World Disaster Management Conference held at the FSA in June of 2007. Two research projects were conducted during Years Two and Three. The first, conducted over a two year period, evaluated student surveys regarding the value of the flammable liquids training received. The second was a needs assessment conducted for rural Nevada. Both projects provided important feedback and a basis for curricula development and improvements.

  8. The impact of different cooling modalities on the physiological responses in firefighters during strenuous work performed in high environmental temperatures.

    Science.gov (United States)

    Barr, David; Reilly, Thomas; Gregson, Warren

    2011-06-01

    This study investigated the impact of ice vests and hand/forearm immersion on accelerating the physiological recovery between two bouts of strenuous exercise in the heat [mean (SD), 49.1(1.3)°C, RH 12 (1)]. On four occasions, eight firefighters completed two 20-min bouts of treadmill walking (5 km h, 7.5% gradient) while wearing standard firefighter protective clothing. Each bout was separated by a 15-min recovery period, during which one of four conditions were administered: ice vest (VEST), hand/forearm immersion (W), ice vest combined with hand/forearm immersion (VEST + W) and control (CON). Core temperature was significantly lower at the end of the recovery period in the VEST + W (37.97 ± 0.23°C) and W (37.96 ± 0.19°C) compared with the VEST (38.21 ± 0.12°C) and CON (38.29 ± 0.25°C) conditions and remained consistently lower throughout the second bout of exercise. Heart rate responses during the recovery period and bout 2 were similar between the VEST + W and W conditions which were significantly lower compared with the VEST and CON which did not differ from each other. Mean skin temperature was significantly lower at the start of bout 2 in the cooling conditions compared with CON; these differences reduced as exercise progressed. These findings demonstrate that hand/forearm immersion (~19°C) is more effective than ice vests in reducing the physiological strain when firefighters re-enter structural fires after short rest periods. Combining ice vests with hand/forearm immersion provides no additional benefit.

  9. A Stochastic Integer Programming Model for Minimizing Cost in the Use of Rain Water Collectors for Firefighting

    Directory of Open Access Journals (Sweden)

    Luis A. Rivera-Morales

    2014-01-01

    Full Text Available In this paper we propose a stochastic integer programming optimization model to determine the optimal location and number of rain water collectors (RWCs for forest firefighting. The objective is to minimize expected total cost to control forest fires. The model is tested using a real case and several additional realistic scenarios. The impact on the solution of varying the limit on the number of RWCs, the RWC water capacity, the aircraft capacity, the water demands, and the aircraft operating cost is explored. Some observations are that the objective value improves with larger RWCs and with the use of aircraft with greater capacity.

  10. Effect of Menthol on Respiratory and Perceptual Responses to Exercise in Firefighter Protective Gear

    Directory of Open Access Journals (Sweden)

    Yang Zhang

    2015-09-01

    Full Text Available Impaired respiration reduces firefighters’ work capacity. This study evaluated the effect of menthol lozenge on respiratory and perceptual responses during exercise in a hot environment. Ten participants wearing firefighter protective gear performed two repeated exercise and rest trials in a counter-balanced order. Exercise consisted of two bouts of 20-min treadmill exercise at 60% of maximal oxygen uptake and one bout of 20-min stepping exercise at a wet bulb global temperature of 35°C. Participants either took 10-mg menthol or control lozenges prior to the beginning of each exercise bout. Respiratory gas exchange, heart rate, thermal sensation, and breathing comfort were continuously recorded. Menthol lozenges significantly increased pulmonary ventilation (menthol: 45.0±6.6 L•min-1 vs. control: 41.4±5.8 L•min-1 and menthol: 52.7±9.7 L•min-1 vs. control: 46.5±7.0 L•min-1, for the 1st and 2nd treadmill exercise, respectively and oxygen consumption (menthol: 26.7±2.0 ml•kg-1•min-1 vs. control: 25.2±2.3 ml•kg-1•min-1 and menthol: 28.8±2.3 ml•kg-1•min-1 vs. control: 26.9±1.9 ml•kg-1•min-1, for the 1st and 2nd treadmill exercise, respe¬cti¬ve¬ly (p0.05. The ventilatory equivalents though were not different throughout the exercise (p>0.05. Ratings of thermal sensation and breathing comfort were not different (p>0.05. It was concluded that menthol could alter breathing pattern and increase respiratory responses during strenuous exercise in the heat. There was no favorable effect of menthol on respiratory or perceptual responses under exercise-heat stress.

  11. High capacity carbon dioxide sorbent

    Science.gov (United States)

    Dietz, Steven Dean; Alptekin, Gokhan; Jayaraman, Ambalavanan

    2015-09-01

    The present invention provides a sorbent for the removal of carbon dioxide from gas streams, comprising: a CO.sub.2 capacity of at least 9 weight percent when measured at 22.degree. C. and 1 atmosphere; an H.sub.2O capacity of at most 15 weight percent when measured at 25.degree. C. and 1 atmosphere; and an isosteric heat of adsorption of from 5 to 8.5 kilocalories per mole of CO.sub.2. The invention also provides a carbon sorbent in a powder, a granular or a pellet form for the removal of carbon dioxide from gas streams, comprising: a carbon content of at least 90 weight percent; a nitrogen content of at least 1 weight percent; an oxygen content of at most 3 weight percent; a BET surface area from 50 to 2600 m.sup.2/g; and a DFT micropore volume from 0.04 to 0.8 cc/g.

  12. Stable High-Capacity Lithium Ion Battery Anodes Produced by Supersonic Spray Deposition of Hematite Nanoparticles and Self-Healing Reduced Graphene Oxide

    International Nuclear Information System (INIS)

    Lee, Jong-Gun; Joshi, Bhavana N.; Lee, Jong-Hyuk; Kim, Tae-Gun; Kim, Do-Yeon; Al-Deyab, Salem S.; Seong, Il Won; Swihart, Mark T.; Yoon, Woo Young; Yoon, Sam S.

    2017-01-01

    Hematite (Fe 2 O 3 ) nanoparticles and reduced graphene oxide (rGO) were supersonically sprayed onto copper current collectors to create high-performance, binder-free lithium ion battery (LIB) electrodes. Supersonic spray deposition is rapid, low-cost, and suitable for large-scale production. Supersonic impact of rGO sheets and Fe 2 O 3 nanoparticles on the substrate produces compacted nanocomposite films with short diffusion lengths for Li + ions. This structure produces high reversible capacity and markedly improved capacity retention over many cycles. Decomposition of lithium oxide generated during cycling activates the solid electrolyte interface layer, contributing to high capacity retention. The optimal composition ratio of rGO to Fe 2 O 3 was 9.1 wt.%, which produced a reversible capacity of 1242 mAh g −1 after N = 305 cycles at a current density of 1000 mA g −1 (1C).

  13. Psychological factors influence the gastroesophageal reflux disease (GERD) and their effect on quality of life among firefighters in South Korea.

    Science.gov (United States)

    Jang, Seung-Ho; Ryu, Han-Seung; Choi, Suck-Chei; Lee, Sang-Yeol

    2016-10-01

    The purpose of this study was to examine psychosocial factors related to gastroesophageal reflux disease (GERD) and their effects on quality of life (QOL) in firefighters. Data were collected from 1217 firefighters in a Korean province. We measured psychological symptoms using the scale. In order to observe the influence of the high-risk group on occupational stress, we conduct logistic multiple linear regression. The correlation between psychological factors and QOL was also analyzed and performed a hierarchical regression analysis. GERD was observed in 32.2% of subjects. Subjects with GERD showed higher depressive symptom, anxiety and occupational stress scores, and lower self-esteem and QOL scores relative to those observed in GERD - negative subject. GERD risk was higher for the following occupational stress subcategories: job demand, lack of reward, interpersonal conflict, and occupational climate. The stepwise regression analysis showed that depressive symptoms, occupational stress, self-esteem, and anxiety were the best predictors of QOL. The results suggest that psychological and medical approaches should be combined in GERD assessment.

  14. Do Teachers Make Decisions Like Firefighters? Applying Naturalistic Decision-Making Methods to Teachers' In-Class Decision Making in Mathematics

    Science.gov (United States)

    Jazby, Dan

    2014-01-01

    Research into human decision making (DM) processes from outside of education paint a different picture of DM than current DM models in education. This pilot study assesses the use of critical decision method (CDM)--developed from observations of firefighters' DM -- in the context of primary mathematics teachers' in-class DM. Preliminary results…

  15. An Educational Intervention for Police and Firefighters for Elders at Risk: Limits of Education Alone as a Strategy for Behavior Change

    Science.gov (United States)

    Nusbaum, N. J.; Mistretta, M.; Wegner, J.

    2007-01-01

    As part of a research project aimed at the health care needs of the vulnerable community-dwelling elderly, an educational intervention was delivered to police and firefighters in worksite settings. A single educational intervention proved insufficient to produce lasting attitudinal and behavioral change as measured by follow-up surveys 3 and 6…

  16. New Ways of Learning to Fight Fires? Learning Processes and Contradictions in Distance and On-Campus Firefighter Training in Sweden

    Science.gov (United States)

    Holmgren, Robert

    2015-01-01

    This article reports on findings from a comparative study on firefighter students' learning processes in a technology-supported distance training course and a traditional campus training course in Sweden. Based on student interviews and observations of exercises, the article aims to describe and analyse the impact on learning processes when…

  17. Measurement of functional capacity requirements to aid in development of an occupation-specific rehabilitation training program to help firefighters with cardiac disease safely return to work.

    Science.gov (United States)

    Adams, Jenny; Roberts, Joanne; Simms, Kay; Cheng, Dunlei; Hartman, Julie; Bartlett, Charles

    2009-03-15

    We designed a study to measure the functional capacity requirements of firefighters to aid in the development of an occupation-specific training program in cardiac rehabilitation; 23 healthy male firefighters with no history of heart disease completed a fire and rescue obstacle course that simulated 7 common firefighting tasks. They wore complete personal protective equipment and portable metabolic instruments that included a data collection mask. We monitored each subject's oxygen consumption (VO(2)) and working heart rate, then calculated age-predicted maximum heart rates (220 - age) and training target heart rates (85% of age-predicted maximum heart rate). During performance of the obstacle course, the subjects' mean working heart rates and peak heart rates were higher than the calculated training target heart rates (t(22) = 5.69 [working vs target, p functional capacity greatly exceeded that typically attained by patients in traditional cardiac rehabilitation programs (5 to 8 METs). In conclusion, our results indicate the need for intense, occupation-specific cardiac rehabilitation training that will help firefighters safely return to work after a cardiac event.

  18. Cold-water immersion and iced-slush ingestion are effective at cooling firefighters following a simulated search and rescue task in a hot environment.

    Science.gov (United States)

    Walker, Anthony; Driller, Matthew; Brearley, Matt; Argus, Christos; Rattray, Ben

    2014-10-01

    Firefighters are exposed to hot environments, which results in elevated core temperatures. Rapidly reducing core temperatures will likely increase safety as firefighters are redeployed to subsequent operational tasks. This study investigated the effectiveness of cold-water immersion (CWI) and iced-slush ingestion (SLUSH) to cool firefighters post-incident. Seventy-four Australian firefighters (mean ± SD age: 38.9 ± 9.0 years) undertook a simulated search and rescue task in a heat chamber (105 ± 5 °C). Testing involved two 20-min work cycles separated by a 10-min rest period. Ambient temperature during recovery periods was 19.3 ± 2.7 °C. Participants were randomly assigned one of three 15-min cooling protocols: (i) CWI, 15 °C to umbilicus; (ii) SLUSH, 7 g·kg(-1) body weight; or (iii) seated rest (CONT). Core temperature and strength were measured pre- and postsimulation and directly after cooling. Mean temperatures for all groups reached 38.9 ± 0.9 °C at the conclusion of the second work task. Both CWI and SLUSH delivered cooling rates in excess of CONT (0.093 and 0.092 compared with 0.058 °C·min(-1)) and reduced temperatures to baseline measurements within the 15-min cooling period. Grip strength was not negatively impacted by either SLUSH or CONT. CWI and SLUSH provide evidence-based alternatives to passive recovery and forearm immersion protocols currently adopted by many fire services. To maximise the likelihood of adoption, we recommend SLUSH ingestion as a practical and effective cooling strategy for post-incident cooling of firefighters in temperate regions.

  19. The management of heat stress for the firefighter: a review of work conducted on behalf of the Toronto Fire Service.

    Science.gov (United States)

    McLellan, Tom M; Selkirk, Glen A

    2006-07-01

    This report provides a summary of research conducted through a grant provided by the Workplace Safety Insurance Board of Ontario. The research was divided into two phases; first, to define safe work limits for firefighters wearing their protective clothing and working in warm environments; and, the second, to examine strategies to reduce the thermal burden and extend the operational effectiveness of the firefighter. For the first phase, subjects wore their protective ensemble and carried their self-contained breathing apparatus (SCBA) and performed very light, light, moderate or heavy work at 25 degrees C, 30 degrees C or 35 degrees C. Thermal and evaporative resistance coefficients were obtained from thermal manikin testing that allowed the human physiological responses to be compared with modeled data. Predicted continuous work times were then generated using a heat strain model that established limits for increases in body temperature to 38.0 degrees C, 38.5 degrees C and 39.0 degrees C. Three experiments were conducted for the second phase of the project. The first study revealed that replacing the duty uniform pants that are worn under the bunker pants with shorts reduced the thermal strain for activities that lasted longer than 60 min. The second study examined the importance of fluid replacement. The data revealed that fluid replacement equivalent to at least 65% of the sweat lost increased exposure time by 15% compared with no fluid replacement. The last experiment compared active and passive cooling. Both the use of a mister or forearm and hand submersion in cool water significantly increased exposure time compared with passive cooling that involved only removing most of the protective clothing. Forearm and hand submersion proved to be most effective and produced dramatic increases in exposure time that approximated 65% compared with the passive cooling procedure. When the condition of no fluid replacement and passive cooling was compared with fluid

  20. Multiwalled carbon nanotube@a-C@Co9S8 nanocomposites: a high-capacity and long-life anode material for advanced lithium ion batteries

    Science.gov (United States)

    Zhou, Yanli; Yan, Dong; Xu, Huayun; Liu, Shuo; Yang, Jian; Qian, Yitai

    2015-02-01

    A one-dimensional MWCNT@a-C@Co9S8 nanocomposite has been prepared via a facile solvothermal reaction followed by a calcination process. The amorphous carbon layer between Co9S8 and MWCNT acts as a linker to increase the loading of sulfides on MWCNT. When evaluated as anode materials for lithium ion batteries, the MWCNT@a-C@Co9S8 nanocomposite shows the advantages of high capacity and long life, superior to Co9S8 nanoparticles and MWCNT@Co9S8 nanocomposites. The reversible capacity could be retained at 662 mA h g-1 after 120 cycles at 1 A g-1. The efficient synthesis and excellent performances of this nanocomposite offer numerous opportunities for other sulfides as a new anode for lithium ion batteries.A one-dimensional MWCNT@a-C@Co9S8 nanocomposite has been prepared via a facile solvothermal reaction followed by a calcination process. The amorphous carbon layer between Co9S8 and MWCNT acts as a linker to increase the loading of sulfides on MWCNT. When evaluated as anode materials for lithium ion batteries, the MWCNT@a-C@Co9S8 nanocomposite shows the advantages of high capacity and long life, superior to Co9S8 nanoparticles and MWCNT@Co9S8 nanocomposites. The reversible capacity could be retained at 662 mA h g-1 after 120 cycles at 1 A g-1. The efficient synthesis and excellent performances of this nanocomposite offer numerous opportunities for other sulfides as a new anode for lithium ion batteries. Electronic supplementary information (ESI) available: Infrared spectrogram (IR) of glucose treated MWCNT; TEM images of MWCNT@a-C treated by different concentrations of glucose; SEM and TEM images of the intermediate product obtained from the solvothermal reaction between thiourea and Co(Ac)2; EDS spectrum of MWCNT@a-C@Co9S8 composites; SEM and TEM images of MWCNT@Co9S8 nanocomposites obtained without the hydrothermal treatment by glucose; SEM and TEM images of Co9S8 nanoparticles; Galvanostatic discharge-charge profiles and cycling performance of MWCNT@a-C; TEM images

  1. Final Project Report for DOE/EERE High-Capacity and Low-Cost Hydrogen-Storage Sorbents for Automotive Applications

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Hong-Cai [Texas A & M Univ., College Station, TX (United States); Liu, Di-Jia [Texas A & M Univ., College Station, TX (United States)

    2017-12-01

    This report provides a review of the objectives, progress, and milestones of the research conducted during this project on the topic of developing innovative metal-organic frameworks (MOFs) and porous organic polymers (POPs) for high-capacity and low-cost hydrogen-storage sorbents in automotive applications.1 The objectives of the proposed research were to develop new materials as next-generation hydrogen storage sorbents that meet or exceed DOE’s 2017 performance targets of gravimetric capacity of 0.055 kg H2/kgsystem and volumetric capacity of 0.040 kg H2/Lsystem at a cost of $400/kg H2 stored. Texas A&M University (TAMU) and Argonne National Laboratory (ANL) collaborated in developing low-cost and high-capacity hydrogen-storage sorbents with appropriate stability, sorption kinetics, and thermal conductivity. The research scope and methods developed to achieve the project’s goals include the following: Advanced ligand design and synthesis to construct MOF sorbents with optimal hydrogen storage capacities, low cost and high stability; Substantially improve the hydrogen uptake capacity and chemical stability of MOF-based sorbents by incorporating high valent metal ions during synthesis or through the post-synthetic metal metathesis oxidation approach; Enhance sorbent storage capacity through material engineering and characterization; Generate a better understanding of the H2-sorbent interaction through advanced characterization and simulation. Over the course of the project 5 different MOFs were developed and studied: PCN-250, PCN-12, PCN-12’, PCN-608 and PCN-609.2-3 Two different samples were submitted to the National Renewable Energy Laboratory (NREL) in order to validate their hydrogen adsorption capacity, PCN-250 and PCN-12. Neither of these samples reached the project’s Go/No-Go requirements but the data obtained did further prove the hypothesis that the presence of open metal

  2. Proposal for the conclusion of a partnership agreement, without competitive tendering, for the management of medical emergencies on the CERN site and the training of CERN's medical staff and firefighters in emergency situations

    CERN Document Server

    2014-01-01

    Proposal for the conclusion of a partnership agreement, without competitive tendering, for the management of medical emergencies on the CERN site and the training of CERN's medical staff and firefighters in emergency situations

  3. High Capacity of Hard Carbon Anode in Na-Ion Batteries Unlocked by PO x Doping

    Energy Technology Data Exchange (ETDEWEB)

    Li, Zhifei; Ma, Lu; Surta, Todd Wesley; Bommier, Clement; Jian, Zelang; Xing, Zhenyu; Stickle, William F.; Dolgos, Michelle; Amine, Khalil; Lu, Jun; Wu, Tianpin; Ji, Xiulei

    2016-08-12

    The capacity of hard carbon anodes in Na-ion batteries 2.5 rarely reaches values beyond 300 mAh/g. We report that doping POx into local structures of hard carbon increases its reversible capacity from 283 to 359 mAh/g. We confirm that the doped POx is redox inactive by X-ray adsorption near edge structure measurements, thus not contributing to the higher capacity. We observe two significant changes of hard carbon's local structures caused by doping. First, the (002) d-spacing inside the turbostratic nanodomains is increased, revealed by both laboratory and synchrotron X-ray diffraction. Second, doping turns turbostratic nanodomains more defective along ab planes, indicated by neutron total scattering and the associated pair distribution function studies. The local structural changes of hard carbon are correlated to the higher capacity, where both the plateau and slope regions in the potential profiles are enhanced. Our study demonstrates that Na-ion storage in hard carbon heavily depends on carbon local structures, where such structures, despite being disordered, can be tuned toward unusually high capacities.

  4. High-capacity hollow porous dummy molecular imprinted polymers using ionic liquid as functional monomer for selective recognition of salicylic acid.

    Science.gov (United States)

    Xiang, Haiyan; Peng, Mijun; Li, Hui; Peng, Sheng; Shi, Shuyun

    2017-01-30

    The existence of strong intramolecular hydrogen bond in salicylic acid (SA) weakens its intermolecular hydrogen bonding with functional monomer, then it is a challenge work to fabricate molecularly imprinted polymers (MIPs) for SA recognition with high capacity and good selectivity. Here, hollow porous dummy MIPs (HPDMIPs) were prepared using benzoic acid (BA) as dummy template, ionic liquid (i.e. 1-vinyl-3-methylimidazolium chloride) as functional monomer, and MCM-48 as sacrificial support. Factors that affected adsorption, such as type of template and porogen, mole ratio of template-functional monomer-cross-linker and type of binding solvent, were optimized in detail. Multiple strong interactions between SA and ionic liquid in HPDMIPs deduced higher binding capacity (29.75mg/g), imprinting factor (5.61) and selectivity than any previously reported MIPs by traditional or surface imprinting technology. The large surface area (543.9m 2 /g) with hollow porous structure resulted in faster kinetic binding (25min). The equilibrium data fitted well to Freundlich equation and the adsorption process could be described by pseudo-second order model. Finally, HPDMIPs were successfully applied to selectively extract and enrich SA from Actinidia chinensis with a relatively high recovery (84.6-94.5%). Copyright © 2016 Elsevier B.V. All rights reserved.

  5. Three-dimensionally interconnected Si frameworks derived from natural halloysite clay: a high-capacity anode material for lithium-ion batteries.

    Science.gov (United States)

    Wan, Hao; Xiong, Hao; Liu, Xiaohe; Chen, Gen; Zhang, Ning; Wang, Haidong; Ma, Renzhi; Qiu, Guanzhou

    2018-05-23

    On account of its high theoretical capacity, silicon (Si) has been regarded as a promising anode material for Li-ion batteries. Extracting Si content from earth-abundant and low-cost aluminosilicate minerals, rather than from artificial silica (SiO2) precursors, is a more favorable and practical method for the large-scale application of Si anodes. In this work, three-dimensionally interconnected (3D-interconnected) Si frameworks with a branch diameter of ∼15 nm are prepared by the reduction of amorphous SiO2 nanotubes derived from natural halloysite clay. Benefiting from their nanostructure, the as-prepared 3D-interconnected Si frameworks yield high reversible capacities of 2.54 A h g-1 at 0.1 A g-1 after 50 cycles, 1.87 A h g-1 at 0.5 A g-1 after 200 cycles, and 0.97 A h g-1 at 2 A g-1 after a long-term charge-discharge process of 500 cycles, remarkably outperforming the commercial Si material. Further, when the as-prepared Si frameworks and commercial LiCoO2 cathodes are paired in full cells, a high anode capacity of 0.98 A h g-1 is achieved after 100 cycles of rapid charge/discharge at 2 A g-1. This work provides a new strategy for the synthesis of high-capacity Si anodes derived from natural aluminosilicate clay.

  6. Numerical and Experimental Study on Manufacture of a Novel High-Capacity Engine Oil Pan Subjected to Hydro-Mechanical Deep Drawing

    Science.gov (United States)

    Chen, D. Y.; Xu, Y.; Zhang, S. H.; El-Aty, A. Abd; Ma, Y.

    2017-09-01

    The oil pan is equipped at the bottom of engine crankcase of the automobile to prevent impurity and collect the lubrication oil from the surfaces of the engine which is helpful for heat dissipation and oxidation prevention. The present study aims at manufacturing a novel high-capacity engine oil pan, which is considered as a complex shaped component with features of thin wall, large size and asymmetric deep cavity through both numerical and experimental methods. The result indicated that it is difficult to form the current part through the common deep drawing process. Accordingly, the hydro-mechanical deep drawing technology was conducted, which consisted of two steps, previous local drawing and the final integral deep drawing with hydraulic pressure. The finite element analysis (FEA) was carried out to investigate the influence of initial blank dimension and the key process parameters such as loading path, draw-bead force and fillet radius on the formability of the sheet blank. Compared with the common deep drawing, the limit drawing ratio by hydro-mechanical deep drawing can be increased from 2.34 to 2.77, while the reduction in blank wall thickness can be controlled in the range of 28%. The formability is greatly improved without any defects such as crack and wrinkle by means of parameters optimisation. The results gained from simulation keep a reasonable agreement with that obtained from experiment trials.

  7. Characterization of the cloned full-length and a truncated human target of rapamycin: Activity, specificity, and enzyme inhibition as studied by a high capacity assay

    International Nuclear Information System (INIS)

    Toral-Barza, Lourdes; Zhang Weiguo; Lamison, Craig; LaRocque, James; Gibbons, James; Yu, Ker

    2005-01-01

    The mammalian target of rapamycin (mTOR/TOR) is implicated in cancer and other human disorders and thus an important target for therapeutic intervention. To study human TOR in vitro, we have produced in large scale both the full-length TOR (289 kDa) and a truncated TOR (132 kDa) from HEK293 cells. Both enzymes demonstrated a robust and specific catalytic activity towards the physiological substrate proteins, p70 S6 ribosomal protein kinase 1 (p70S6K1) and eIF4E binding protein 1 (4EBP1), as measured by phosphor-specific antibodies in Western blotting. We developed a high capacity dissociation-enhanced lanthanide fluorescence immunoassay (DELFIA) for analysis of kinetic parameters. The Michaelis constant (K m ) values of TOR for ATP and the His6-S6K substrate were shown to be 50 and 0.8 μM, respectively. Dose-response and inhibition mechanisms of several known inhibitors, the rapamycin-FKBP12 complex, wortmannin and LY294002, were also studied in DELFIA. Our data indicate that TOR exhibits kinetic features of those shared by traditional serine/threonine kinases and demonstrate the feasibility for TOR enzyme screen in searching for new inhibitors

  8. Quantifying the environmental impact of a Li-rich high-capacity cathode material in electric vehicles via life cycle assessment.

    Science.gov (United States)

    Wang, Yuqi; Yu, Yajuan; Huang, Kai; Chen, Bo; Deng, Wensheng; Yao, Ying

    2017-01-01

    A promising Li-rich high-capacity cathode material (xLi 2 MnO 3 ·(1-x)LiMn 0.5 Ni 0.5 O 2 ) has received much attention with regard to improving the performance of lithium-ion batteries in electric vehicles. This study presents an environmental impact evaluation of a lithium-ion battery with Li-rich materials used in an electric vehicle throughout the life cycle of the battery. A comparison between this cathode material and a Li-ion cathode material containing cobalt was compiled in this study. The battery use stage was found to play a large role in the total environmental impact and high greenhouse gas emissions. During battery production, cathode material manufacturing has the highest environmental impact due to its complex processing and variety of raw materials. Compared to the cathode with cobalt, the Li-rich material generates fewer impacts in terms of human health and ecosystem quality. Through the life cycle assessment (LCA) results and sensitivity analysis, we found that the electricity mix and energy efficiency significantly influence the environmental impacts of both battery production and battery use. This paper also provides a detailed life cycle inventory, including firsthand data on lithium-ion batteries with Li-rich cathode materials.

  9. Organic cation transporter 2 (SLC22A2), a low-affinity and high-capacity choline transporter, is preferentially enriched on synaptic vesicles in cholinergic neurons.

    Science.gov (United States)

    Nakata, T; Matsui, T; Kobayashi, K; Kobayashi, Y; Anzai, N

    2013-11-12

    Organic cation transporters (OCTs) are expressed mainly in the kidney and liver. OCTs transport intrinsic organic cations, including monoamine, dopamine, serotonine and choline, across the plasma membrane. Here, we demonstrate that OCT2 (SLC22A2) is expressed in cholinergic neurons, motoneurons in the anterior horn of the spinal cord, and is implicated in acetylcholine (Ach) recycling in presynaptic terminals. Application of rabbit anti-peptide antibody revealed that OCT2 was expressed in the anterior horn of the spinal cord. Double immunostaining of muscle sections with anti-OCT2 and alpha-bungarotoxin (BTX) revealed that OCT2 was localized in the neuromuscular junctions (NMJs). Immunoelectron microscopy revealed that OCT2 was localized both in synaptic vesicles (SVs) in presynaptic terminals around the motoneurons (C-terminals) and in SVs in nerve terminals in NMJs. The similarity in the distribution of OCT2 in cholinergic neurons and that of vesicular acetyl choline transporter (VAchT), and the fact that OCT2 can transport choline suggest that OCT2 could work as a low-affinity and high-capacity choline transporter at presynaptic terminals in cholinergic neurons in a firing-dependent manner. Copyright © 2013 IBRO. Published by Elsevier Ltd. All rights reserved.

  10. Efficient fabrication of high-capacity immobilized metal ion affinity chromatographic media: The role of the dextran-grafting process and its manipulation.

    Science.gov (United States)

    Zhao, Lan; Zhang, Jingfei; Huang, Yongdong; Li, Qiang; Zhang, Rongyue; Zhu, Kai; Suo, Jia; Su, Zhiguo; Zhang, Zhigang; Ma, Guanghui

    2016-03-01

    Novel high-capacity Ni(2+) immobilized metal ion affinity chromatographic media were prepared through the dextran-grafting process. Dextran was grafted to an allyl-activated agarose-based matrix followed by functionalization for the immobilized metal ion affinity chromatographic media. With elaborate regulation of the allylation degree, dextran was completely or partly grafted to agarose microspheres, namely, completely dextran-grafted agarose microspheres and partly dextran-grafted ones, respectively. Confocal laser scanning microscope results demonstrated that a good adjustment of dextran-grafting degree was achieved, and dextran was distributed uniformly in whole completely dextran-grafted microspheres, while just distributed around the outside of the partly dextran-grafted ones. Flow hydrodynamic properties were improved greatly after the dextran-grafting process, and the flow velocity increased by about 30% compared with that of a commercial chromatographic medium (Ni Sepharose FF). A significant improvement of protein binding performance was also achieved by the dextran-grafting process, and partly dextran-grafted Ni(2+) chelating medium had a maximum binding capacity for His-tagged lactate dehydrogenase about 2.5 times higher than that of Ni Sepharose FF. The results indicated that this novel chromatographic medium is promising for applications in high-efficiency and large-scale protein purification. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Preparation of high-capacity, weak anion-exchange membranes by surface-initiated atom transfer radical polymerization of poly(glycidyl methacrylate) and subsequent derivatization with diethylamine

    International Nuclear Information System (INIS)

    Qian, Xiaolei; Fan, Hua; Wang, Chaozhan; Wei, Yinmao

    2013-01-01

    Ion-exchange membrane is of importance for the development of membrane chromatography. In this work, a high-capacity anion-exchange membrane was prepared by grafting of glycidyl methacrylate (GMA) onto the surface of regenerated cellulose (RC) membranes via surface-initiated atom transfer radical polymerization (SI-ATRP) and subsequent derivatization with diethylamine. Attenuated total reflectance Fourier-transform infrared (ATR-FTIR), X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM) were used to characterize changes in the chemical functionality, surface topography and pore morphology of the modified membranes. The static capacity of the prepared anion-exchange membrane was evaluated with bovine serum albumin (BSA) as a model protein. The results indicated that the anion-exchange membrane which could reach a maximum capacity of 96 mg/mL for static adsorption possesses a higher adsorption capacity, and the adsorption capacity increases with the polymerization time. The effect of pH and salt concentration confirmed that the adsorption of BSA followed ion-exchange mechanism. The established method would have potential application in the preparation of anion-exchange membrane.

  12. Vasoactive intestinal peptide (VIP) binds to guinea pig peritoneal eosinophils: A single class of binding sites with low affinity and high capacity

    International Nuclear Information System (INIS)

    Sakakibara, H.; Shima, K.; Takamatsu, J.; Said, S.I.

    1990-01-01

    VIP binds to specific receptors on lymphocytes and mononuclear cells and exhibits antiinflammatory properties. Eosinophils (Eos) contribute to inflammatory reactions but the regulation of Eos function is incompletely understood. The authors examined the binding of monoradioiodinated VIP, [Tyr( 125 I) 10 ] VIP ( 125 I-VIP), to Eos in guinea pigs. The interaction of 125 i-VIP with Eos was rapid, reversible, saturable and linearly dependent on the number of cells. At equilibrium the binding was competitively inhibited by native peptide or by the related peptide helodermin. Scatchard analysis suggested the presence of a single class of VIP binding sites with a low affinity and a high capacity. In the presence of isobutyl-methylxanthine, VIP, PHI or helodermin did not stimulate cyclic AMP accumulation in intact Eos, while PGE 2 or 1-isoproterenol did. VIP also did not inhibit superoxide anion generation from Eos stimulated by phorbol myristate acetate. The authors conclude that: (1) VIP binds to low-affinity, specific sites on guinea pig peritoneal eosinophils; (2) this binding is not coupled to stimulation of adenylate cyclase; and (3) the possible function of these binding sites is at present unknown

  13. Three-dimensional hierarchical porous flower-like nickel-cobalt oxide/multi-walled carbon nanotubes nanocomposite for high-capacity supercapacitors

    International Nuclear Information System (INIS)

    Liu, Peipei; Hu, Zhonghua; Liu, Yafei; Yao, Mingming; Zhang, Qiang

    2015-01-01

    Highlights: • 3D hierarchical porous flower-like Ni-Co oxide/MWCNTs was synthesized. • The electrode shows a large specific surface area and desirable mesoporosity. • High specific capacitances and outstanding stability were obtained. • The content of MWCNTs affects the electrochemical properties of the electrode. - Abstract: Three-dimensional (3D) hierarchical porous flower-like nickel-cobalt oxide/multi-walled carbon nanotubes (Ni-Co oxide/MWCNTs) nanocomposites were fabricated by a facile and template-free hydrothermal method as electrodes for high-capacity supercapacitors. The samples were characterized by energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption-desorption and thermal gravimetric analysis (TGA). The electrochemical performance was investigated by cyclic voltammetry (CV), galvanostatic charge-discharge, and cycle life. It was found that Ni-Co oxide/MWCNTs nanocomposites displayed a high specific capacitance (1703 F g −1 at a discharge current density of 1 A g −1 ) and, additionally, an excellent cycling performance, retaining 97% of the maximum capacitance after 2000 cycles at 10 A g −1 . Even at a high current density (20 A g −1 ), the specific capacitance was still up to 1309 F g −1 . This outstanding capacitive performance may be attributed to the ideal composition of the material and to its unique 3D hierarchical porous flower-like architecture

  14. Determination of airborne, volatile amines from polyurethane foams by sorption onto a high-capacity cation-exchange resin based on poly(succinic acid).

    Science.gov (United States)

    Seeber, G; Buchmeiser, M R; Bonn, G K; Bertsch, T

    1998-06-05

    A high-capacity carboxylic acid-functionalized resin prepared by ring-opening metathesis polymerization based on cross-linked endo,endo-poly(norborn-2-ene-5,6-dicarboxylic acid) was used for the sampling of volatile, airborne amines from polyurethane (PU) foams. Six tertiary amines which represent commonly used promotors for the formation of PUs from diisocyanates and polyols, namely pentamethyldiethylenetriamine, diazabicyclooctane, N-methylmorpholine, N-ethylmorphine, 1,4-dimethylpiperazine and N,N-dimethylethanolamine, were sorbed onto the new resin. The sorption behavior of the new material was investigated in terms of loading capacities, the influence of concentration, flow-rate as well as of the amount of resin. Breakthrough curves were recorded from each single component as well as of mixtures thereof. Finally, the resin was used for the sampling of amines evaporating from PU foams applied in buildings. Further information about time dependent concentration profiles were obtained using a combination of GC-MS and Fourier transform IR spectroscopy.

  15. The toxic exposure of flamingos to per- and Polyfluoroalkyl substances (PFAS) from firefighting foam applications in Bonaire.

    Science.gov (United States)

    de Vries, Pepijn; Slijkerman, Diana M E; Kwadijk, Christiaan J A F; Kotterman, Michiel J J; Posthuma, Leo; de Zwart, Dick; Murk, Albertinka J; Foekema, Edwin M

    2017-11-15

    In 2010 an oil terminal next to nature reservation Saliña Goto (Bonaire) caught fire. Firefighting resulted in elevated per- and polyfluoroalkyl substances (PFAS) concentrations in the salt lake. Within months flamingo abundance in Goto dropped to near complete absence. After statistical analysis, rainfall was deemed an unlikely cause for this decline. Toxicological effects on abundance of prey are likely the main cause for the flamingo absence. This reduced PFAS exposure via food and thus risk towards flamingos during the first years after the fires. Although the sediment is still polluted with persistent PFAS, flamingos returned, and started to feed on organisms with PFAS levels that exceed safety thresholds, placing the birds and other wildlife at risk. Monitoring bird populations is advised to assess potential toxic effects on birds and their offspring. This case suggests that applying persistent chemicals to reduce incident impacts may be more harmful than the incident itself. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Cooling hyperthermic firefighters by immersing forearms and hands in 10 degrees C and 20 degrees C water.

    Science.gov (United States)

    Giesbrecht, Gordon G; Jamieson, Christopher; Cahill, Farrell

    2007-06-01

    Firefighters experience significant heat stress while working with heavy gear in a hot, humid environment. This study compared the cooling effectiveness of immersing the forearms and hands in 10 and 20 degrees C water. Six men (33 +/- 10 yr; 180 +/- 4 cm; 78 +/- 9 kg; 19 +/- 5% body fat) wore firefighter 'turn-out gear' (heavy clothing and breathing apparatus weighing 27 kg) in a protocol including three 20-min exercise bouts (step test, 78 W, 40 degrees C air, 40% RH) each followed by a 20-min rest/cooling (21 degrees C air); i.e., 60 min of exercise, 60 min of cooling. Turn-out gear was removed during rest/cooling periods and subjects either rested (Control), immersed their hands in 10 or 20 degrees C water (H-10, H-20), or immersed their hands and forearms in 10 or 20 degrees C water (HF-10, HF-20). In 20 degrees C water, hand immersion did not reduce core temperature compared with Control; however, including forearm immersion decreased core temperature below Control values after both the second and final exercise periods (p hand immersion produced a lower core temperature (0.8 degrees C above baseline) than all other conditions (1.1 to 1.4 degrees C above baseline) after the final exercise period (p Hand and forearm immersion in cool water is simple, reduces heat strain, and may increase work performance in a hot, humid environment. With 20 degrees C water, forearms should be immersed with the hands to be effective. At lower water temperatures, forearm and/or hand immersion will be effective, although forearm immersion will decrease core temperature further.

  17. Three-dimensional hierarchical porous flower-like nickel-cobalt oxide/multi-walled carbon nanotubes nanocomposite for high-capacity supercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Peipei; Hu, Zhonghua, E-mail: huzh@tongji.edu.cn; Liu, Yafei; Yao, Mingming; Zhang, Qiang

    2015-02-15

    Highlights: • 3D hierarchical porous flower-like Ni-Co oxide/MWCNTs was synthesized. • The electrode shows a large specific surface area and desirable mesoporosity. • High specific capacitances and outstanding stability were obtained. • The content of MWCNTs affects the electrochemical properties of the electrode. - Abstract: Three-dimensional (3D) hierarchical porous flower-like nickel-cobalt oxide/multi-walled carbon nanotubes (Ni-Co oxide/MWCNTs) nanocomposites were fabricated by a facile and template-free hydrothermal method as electrodes for high-capacity supercapacitors. The samples were characterized by energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscopy (SEM), transmission electron microscopy (TEM), nitrogen adsorption-desorption and thermal gravimetric analysis (TGA). The electrochemical performance was investigated by cyclic voltammetry (CV), galvanostatic charge-discharge, and cycle life. It was found that Ni-Co oxide/MWCNTs nanocomposites displayed a high specific capacitance (1703 F g{sup −1} at a discharge current density of 1 A g{sup −1}) and, additionally, an excellent cycling performance, retaining 97% of the maximum capacitance after 2000 cycles at 10 A g{sup −1}. Even at a high current density (20 A g{sup −1}), the specific capacitance was still up to 1309 F g{sup −1}. This outstanding capacitive performance may be attributed to the ideal composition of the material and to its unique 3D hierarchical porous flower-like architecture.

  18. Environmentally benign and scalable synthesis of LiFePO4 nanoplates with high capacity and excellent rate cycling performance for lithium ion batteries

    International Nuclear Information System (INIS)

    Zhao, Chunsong; Wang, Lu-Ning; Chen, Jitao; Gao, Min

    2017-01-01

    Highlights: •LiFePO 4 precursors were successfully prepared in pure water phase under atmosphere. •LiFePO 4 nanostructures were also regenerated by recycling filtrate. •LiFePO 4 /C delivers high discharge capacity of 160 mAh g −1 at 0.2 C and high rate capacity of 107 mAh g −1 at 20C. •LiFePO 4 /C delivers a capacity retention rate closed to 97% after 240 cycles at 20C. -- Abstract: An economical and scalable synthesis route of LiFePO 4 nanoplate precursors is successfully prepared in pure water phase under atmosphere without employing environmentally toxic surfactants or high temperature and high pressure compared with traditional hydrothermal or solvothermal methods, which also involves recycling the filtrate to regenerate LiFePO 4 nanoplate precursors and collecting by-product Na 2 SO 4 . The LiFePO 4 precursors present a plate-like morphology with mean thickness and length of 50–100 and 100–300 nm, respectively. After carbon coating, the LiFePO 4 /C nanoparticles with particle size around 200 nm can be observed which exhibit a high discharge capacity of 160 mAh g −1 at 0.2 C and 107 mAh g −1 at 20 C. A high capacity retention closed to 91% can be reached after 500 cycles even at a high current rate of 20C with coulombic efficiency of 99.5%. This work suggests a simple, economic and environmentally benign method in preparation of LiFePO 4 /C cathode material for power batteries that would be feasible for large scale industrial production.

  19. High-Capacity and Long-Cycle Life Aqueous Rechargeable Lithium-Ion Battery with the FePO4 Anode.

    Science.gov (United States)

    Wang, Yuesheng; Yang, Shi-Ze; You, Ya; Feng, Zimin; Zhu, Wen; Gariépy, Vincent; Xia, Jiexiang; Commarieu, Basile; Darwiche, Ali; Guerfi, Abdelbast; Zaghib, Karim

    2018-02-28

    Aqueous lithium-ion batteries are emerging as strong candidates for a great variety of energy storage applications because of their low cost, high-rate capability, and high safety. Exciting progress has been made in the search for anode materials with high capacity, low toxicity, and high conductivity; yet, most of the anode materials, because of their low equilibrium voltages, facilitate hydrogen evolution. Here, we show the application of olivine FePO 4 and amorphous FePO 4 ·2H 2 O as anode materials for aqueous lithium-ion batteries. Their capacities reached 163 and 82 mA h/g at a current rate of 0.2 C, respectively. The full cell with an amorphous FePO 4 ·2H 2 O anode maintained 92% capacity after 500 cycles at a current rate of 0.2 C. The acidic aqueous electrolyte in the full cells prevented cathodic oxygen evolution, while the higher equilibrium voltage of FePO 4 avoided hydrogen evolution as well, making them highly stable. A combination of in situ X-ray diffraction analyses and computational studies revealed that olivine FePO 4 still has the biphase reaction in the aqueous electrolyte and that the intercalation pathways in FePO 4 ·2H 2 O form a 2-D mesh. The low cost, high safety, and outstanding electrochemical performance make the full cells with olivine or amorphous hydrated FePO 4 anodes commercially viable configurations for aqueous lithium-ion batteries.

  20. Rationale and design of feeding America's bravest: Mediterranean diet-based intervention to change firefighters' eating habits and improve cardiovascular risk profiles.

    Science.gov (United States)

    Sotos-Prieto, Mercedes; Cash, Sean B; Christophi, Costas A; Folta, Sara; Moffatt, Steven; Muegge, Carolyn; Korre, Maria; Mozaffarian, Dariush; Kales, Stefanos N

    2017-10-01

    Among US firefighters, cardiovascular disease is the leading cause of on-duty death. Poor diet contributes to this burden, but effective strategies to encourage healthy eating in the fire service are not established. "Feeding America's Bravest" motivates firefighters and their families to modify their food culture and reduce cardiometabolic risk profiles by adopting Mediterranean diet principles. Feeding America's Bravest is a cluster-randomized, controlled trial within the 44 stations of the Indianapolis Fire Department, including about 1000 firefighters. It compares a Mediterranean Diet Nutritional Intervention (MDNI) (group 1) vs. usual care (group 2) for 12months; followed by 12months of self-sustained continuation phase in the group 1 and cross-over to Mediterranean Diet Nutritional Intervention in group 2. Group 2 will receive the MDNI for 6months to test the efficacy of a shorter intervention followed by 6months of self-sustained phase. The intervention includes behavioral and environmental components. The primary outcome is 12-month change in Mediterranean diet score comparing group 1 vs. group 2; we will also assess 12- and 24-month change in group 1, and 6- and 12-month change in group 2, from baseline. Secondary outcomes are changes in body weight, body composition and other cardiometabolic risk markers; and correlations between self-reported dietary habits and biomarkers of dietary adherence. This innovative trial tests a novel worksite approach to introduce Mediterranean diet among US firefighters, through multi-pronged MDNI combining evidence-based behavior change strategies with economic incentives, family and peer support and environmental changes, informing recommendations for the US fire service and potentially other similar workforces. NCT02941757. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Searching for Effective Training Solutions for Firefighting: The Analysis of Emergency Responses and Line of Duty Death Reports for Low Frequency, High Risk Events

    Science.gov (United States)

    2017-09-01

    From the more common problems of pre-existing hazardous structures to the rare events of temperature inversion creating a dangerous environment...the Academy’s burn building. These training scenarios allow firefighters to practice search methods while simultaneously dealing with the heat, smoke...fire behavior (RFB), 32 • secondary collapse (SC), • standard op procedures training (SOP), • temperature inversion (TI), • unrestricted flow

  2. The analysis outlining the occurrence and consequences of accidents in the work environment of the firefighters employed by the State Fire Service in Poland in 2008-2013.

    Science.gov (United States)

    Pawlak, Agata; Gotlib, Joanna; Gałązkowski, Robert

    2016-01-01

    Due to the specifics of their work and to being exposed to a wide range of hazards, firefighters working for the State Fire Service (SFS) face the risk of work-related accidents more often than members of other occupational groups. The aim of this paper is to analyze the occurrence and consequences of accidents in the work environment of the SFS officers in Poland between the years 2008-2013. The material analyzed is based on aggregate data collected by the Headquarters of the State Fire Service. Figures regarding accidents in the period between 1 January 2008 and 31 December 2013 show that 8518 work-related accidents occurred in that period and 8635 people were injured. The data shows that neither the number of accidents nor their frequency indicator underwent any significant fluctuations over the 6 years under consideration. The group that is most exposed to accidents on duty in the profession includes active firefighters serving in rescue and fire extinguishment divisions. According to the data, the greatest number of trauma incidents in the SFS between the years 2008-2013 occurred during sporting activities. The predominant cause of these was inappropriate behavior or the lack of proper care. The most frequent injuries sustained during the accidents were broken or fractured bones and sprained joints. Accidents on duty occur significantly more often when firefighters are at their stations, during sporting classes, exercises or maneuvers, than in the course of actual rescue operations. The firefighters of the State Fire Services are insufficiently prepared for their sporting activities. This work is available in Open Access model and licensed under a CC BY-NC 3.0 PL license.

  3. Suicidal thoughts and behaviors among women firefighters: An examination of associated features and comparison of pre-career and career prevalence rates.

    Science.gov (United States)

    Stanley, Ian H; Hom, Melanie A; Spencer-Thomas, Sally; Joiner, Thomas E

    2017-10-15

    Women protective service workers die by suicide at a higher rate than women workers in other occupational groups. However, no study has examined rates and correlates of suicidal thoughts and behaviors among women firefighters, despite the potential for these data to inform suicide screening, prevention, and intervention initiatives. The purpose of this study is to describe and compare pre-career and career rates of suicidal thoughts and behaviors and identify their sociodemographic and occupational correlates among women firefighters. Data were obtained from 313 current U.S. women firefighters who completed a web-based survey (mean age = 37.30y, SD = 9.70y, 92.7% White). Pre-career rates of suicide ideation, plans, attempts, and non-suicidal self-injury (NSSI) were found to be 28.4%, 10.2%, 5.8%, and 11.2%, respectively. Career rates of suicide ideation, plans, attempts, and NSSI were found to be 37.7%, 10.9%, 3.5%, and 9.3%, respectively. Pre-career rates of suicide ideation (OR = 4.760, 95% CI = 2.820-8.034, p harassment) are needed. Copyright © 2017 Elsevier B.V. All rights reserved.

  4. Synthesis and characterization of advanced high capacity cathode active nanomaterials with three integrated spinel-layered phases for Li-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Bulut, Emrah, E-mail: ebulut@sakarya.edu.tr [Department of Chemistry, Sakarya University, 54187 Serdivan, Sakarya (Turkey); Can, Mustafa, E-mail: mstfacan@gmail.com [Vocational School of Arifiye, Sakarya University, 54580 Arifiye, Sakarya (Turkey); Özacar, Mahmut, E-mail: nmozacart@hotmail.com [Department of Chemistry, Sakarya University, 54187 Serdivan, Sakarya (Turkey); Akbulut, Hatem, E-mail: akbulut@Sakarya.edu.tr [Department of Metallurgical and Materials Engineering, Sakarya University, 54187 Serdivan, Sakarya (Turkey)

    2016-06-15

    .1C rate. • High capacity retentions were achieved for undoped and doped materials in 50 cycles.

  5. A kinetic-based sigmoidal model for the polymerase chain reaction and its application to high-capacity absolute quantitative real-time PCR

    Directory of Open Access Journals (Sweden)

    Stewart Don

    2008-05-01

    with the LinReg and Miner automated qPCR data processing packages further demonstrated the superior performance of this kinetic-based methodology. Conclusion Called "linear regression of efficiency" or LRE, this novel kinetic approach confers the ability to conduct high-capacity absolute quantification with unprecedented quality control capabilities. The computational simplicity and recursive nature of LRE quantification also makes it amenable to software implementation, as demonstrated by a prototypic Java program that automates data analysis. This in turn introduces the prospect of conducting absolute quantification with little additional effort beyond that required for the preparation of the amplification reactions.

  6. Exposure-response relationships for select cancer and non-cancer health outcomes in a cohort of U.S. firefighters from San Francisco, Chicago and Philadelphia (1950-2009).

    Science.gov (United States)

    Daniels, Robert D; Bertke, Stephen; Dahm, Matthew M; Yiin, James H; Kubale, Travis L; Hales, Thomas R; Baris, Dalsu; Zahm, Shelia H; Beaumont, James J; Waters, Kathleen M; Pinkerton, Lynne E

    2015-10-01

    To examine exposure-response relationships between surrogates of firefighting exposure and select outcomes among previously studied US career firefighters. Eight cancer and four non-cancer outcomes were examined using conditional logistic regression. Incidence density sampling was used to match each case to 200 controls on attained age. Days accrued in firefighting assignments (exposed-days), run totals (fire-runs) and run times (fire-hours) were used as exposure surrogates. HRs comparing 75th and 25th centiles of lagged cumulative exposures were calculated using loglinear, linear, log-quadratic, power and restricted cubic spline general relative risk models. Piecewise constant models were used to examine risk differences by time since exposure, age at exposure and calendar period. Among 19,309 male firefighters eligible for the study, there were 1333 cancer deaths and 2609 cancer incidence cases. Significant positive associations between fire-hours and lung cancer mortality and incidence were evident. A similar relation between leukaemia mortality and fire-runs was also found. The lung cancer associations were nearly linear in cumulative exposure, while the association with leukaemia mortality was attenuated at higher exposure levels and greater for recent exposures. Significant negative associations were evident for the exposure surrogates and colorectal and prostate cancers, suggesting a healthy worker survivor effect possibly enhanced by medical screening. Lung cancer and leukaemia mortality risks were modestly increasing with firefighter exposures. These findings add to evidence of a causal association between firefighting and cancer. Nevertheless, small effects merit cautious interpretation. We plan to continue to follow the occurrence of disease and injury in this cohort. 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.

  7. Creation of a retrospective job-exposure matrix using surrogate measures of exposure for a cohort of US career firefighters from San Francisco, Chicago and Philadelphia.

    Science.gov (United States)

    Dahm, Matthew M; Bertke, Stephen; Allee, Steve; Daniels, Robert D

    2015-09-01

    To construct a cohort-specific job-exposure matrix (JEM) using surrogate metrics of exposure for a cancer study on career firefighters from the Chicago, Philadelphia and San Francisco Fire Departments. Departmental work history records, along with data on historical annual fire-runs and hours, were collected from 1950 to 2009 and coded into separate databases. These data were used to create a JEM based on standardised job titles and fire apparatus assignments using several surrogate exposure metrics to estimate firefighters' exposure to the combustion byproducts of fire. The metrics included duration of exposure (cumulative time with a standardised exposed job title and assignment), fire-runs (cumulative events of potential fire exposure) and time at fire (cumulative hours of potential fire exposure). The JEM consisted of 2298 unique job titles alongside 16,174 fire apparatus assignments from the three departments, which were collapsed into 15 standardised job titles and 15 standardised job assignments. Correlations were found between fire-runs and time at fires (Pearson coefficient=0.92), duration of exposure and time at fires (Pearson coefficient=0.85), and duration of exposure and fire-runs (Pearson coefficient=0.82). Total misclassification rates were found to be between 16-30% when using duration of employment as an exposure surrogate, which has been traditionally used in most epidemiological studies, compared with using the duration of exposure surrogate metric. The constructed JEM successfully differentiated firefighters based on gradient levels of potential exposure to the combustion byproducts of fire using multiple surrogate exposure metrics. 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.

  8. Use of participant focus groups to identify barriers and facilitators to worksite exercise therapy adherence in randomized controlled trials involving firefighters

    Directory of Open Access Journals (Sweden)

    Mayer JM

    2013-03-01

    Full Text Available John M Mayer,1 James L Nuzzo,1 Simon Dagenais2 1School of Physical Therapy and Rehabilitation Sciences, College of Medicine, University of South Florida, Tampa, FL, 2Palladian Health, West Seneca, NY, USA Background: Firefighters are at increased risk for back injuries, which may be mitigated through exercise therapy to increase trunk muscle endurance. However, long-term adherence to exercise therapy is generally poor, limiting its potential benefits. Focus groups can be used to identify key barriers and facilitators to exercise adherence among study participants. Objective: To explore barriers and facilitators to worksite exercise therapy adherence among firefighters to inform future randomized controlled trials (RCTs. Methods: Participants enrolled in a previous RCT requiring twice-weekly worksite exercise therapy for 24 weeks were asked to take part in moderated focus group discussions centered on eight open-ended questions related to exercise adherence. Responses were analyzed qualitatively using a social ecological framework to identify key intrapersonal, interpersonal, and institutional barriers and potential facilitators to exercise adherence. Results: A total of 27 participants were included in the four focus group discussions, representing 50% of those assigned to a worksite exercise therapy group in the previous RCT, in which only 67% of scheduled exercise therapy sessions were completed. Lack of self-motivation was cited as the key intrapersonal barrier to adherence, while lack of peer support was the key interpersonal barrier reported, and lack of time to exercise during work shifts was the key institutional barrier identified. Conclusion: Focus group discussions identified both key barriers and potential facilitators to increase worksite exercise therapy adherence among firefighters. Future studies should consider educating and reminding participants about the benefits of exercise, providing individual and group incentives based on

  9. Exercise-Based Performance Enhancement and Injury Prevention for Firefighters: Contrasting the Fitness- and Movement-Related Adaptations to Two Training Methodologies.

    Science.gov (United States)

    Frost, David M; Beach, Tyson A C; Callaghan, Jack P; McGill, Stuart M

    2015-09-01

    Using exercise to enhance physical fitness may have little impact on performers' movement patterns beyond the gym environment. This study examined the fitness and movement adaptations exhibited by firefighters in response to 2 training methodologies. Fifty-two firefighters were assigned to a movement-guided fitness (MOV), conventional fitness (FIT), or control (CON) group. Before and after 12 weeks of training, participants performed a fitness evaluation and laboratory-based test. Three-dimensional lumbar spine and frontal plane knee kinematics were quantified. Five whole-body tasks not included in the interventions were used to evaluate the transfer of training. FIT and MOV groups exhibited significant improvements in all aspects of fitness; however, only MOV exhibited improvements in spine and frontal plane knee motion control when performing each transfer task (effect sizes [ESs] of 0.2-1.5). FIT exhibited less controlled spine and frontal plane knee motions while squatting, lunging, pushing, and pulling (ES: 0.2-0.7). More MOV participants (43%) exhibited only positive posttraining changes (i.e., improved control), in comparison with FIT (30%) and CON (23%). Fewer negative posttraining changes were also noted (19, 25, and 36% for MOV, FIT, and CON). These findings suggest that placing an emphasis on how participants move while exercising may be an effective training strategy to elicit behavioral changes beyond the gym environment. For occupational athletes such as firefighters, soldiers, and police officers, this implies that exercise programs designed with a movement-oriented approach to periodization could have a direct impact on their safety and effectiveness by engraining desirable movement patterns that transfer to occupational tasks.

  10. Assessment of serum PCDD, RCDF and PCB levels in firefighters exposed to combustion products during the 1992 ''Irkutskcable'' factory fire in the city of Shelekhov, Russia

    Energy Technology Data Exchange (ETDEWEB)

    Chernyak, Y.; Merinova, A. [Inst. of Occupational Health and Human Ecology of the Siberian Branch of Academy of Medical Sciences, Angarsk (Russian Federation); Grassman, J. [Brooklyn Coll.-CUNY, Health and Nutrition Sciences, Brooklyn, NY (United States); Brodsky, E.; Shelepchikov, A.; Mir-Kadyrova, E.; Feshin, D.; Zhilnikov, V. [Severtsov Inst. of Ecology and Evolution of the Russian Academy of Sciences, Moscow (Russian Federation)

    2004-09-15

    In December 1992, a fire broke out in a warehouse of the ''Irkutskcable'' factory in the city of Shelekhov, Russia. Over the next three days, the fire destroyed four additional factory warehouses. The building in which the factory was located was sufficiently large, twelve-meters high, to permit the entry of firefighters and their trucks during the fire. The total area affected by the fire was 16280 m{sup 2}. The rest of the approximately 60000 m{sup 2} building was not damaged. Temperatures exceeding 600 C deformed the roof causing it to collapse with the resultant ignition of the technical and raw materials kept in the shops and storerooms. Combustion products were drawn into the air systems of the shops and immediate environment. The height of the air emissions during the first hours of the fire reached 100 m. The ignition of 250 tons of cable oil made it impossible for the firefighters to use their closed circuit respirators because of the danger of explosion. Only the firefighters of one division were provided with compressed air equipment, and they worked in the most difficult areas. According to existing records, 522 firefighters and 12 individuals from the factory fire department participated in the fire liquidation. Moreover, 230 teaching officers and students from Irkutsk Firefighters School were involved. The fire destroyed about 1000 tons of various raw materials, mainly polyvinylchloride and polyethylene. The firefighters had varying degrees of involvement with the liquidation of the fire, during which they were exposed to a complex mixture of toxic compounds that contained dioxins. An estimated, 22 to 57 g of dioxins (in I-TEQ{sub DF}) were formed during the fire. Previously, we described the health disorders of this cohort of firefighters in detail. Dioxin toxicity due to the short but intense respiratory exposure could be responsible for the observed health effects. Following is a report of new data examining dioxin levels in 15

  11. Lactic acidosis occurrence during exercises in the smoke chamber in a 53-year-old firefighter with no significant medical history

    Directory of Open Access Journals (Sweden)

    Agata Bronisz

    2014-04-01

    Full Text Available Lactic acidosis is a form of metabolic acidosis with a high anion gap, reduced rate of arterial blood pH under 7.35 mmol/l, and lactic acid concentration over 7 mmol/l. In the literature we can find some descriptions of the cases of lactic acidosis in patients with severe systemic diseases (cancer, acquired immunodeficiency syndrome, sepsis, diabetes with cardiovascular disease and after organ transplantations. We present the case of lactic acidosis in a patient with no chronic disease - a firefighter in whom lactic acidosis has developed during standard exercises in the smoke chamber.

  12. Cardiovascular Disease Biomarkers Predict Susceptibility or Resistance to Lung Injury in World Trade Center Dust Exposed Firefighters

    Science.gov (United States)

    Weiden, Michael D.; Naveed, Bushra; Kwon, Sophia; Cho, Soo Jung; Comfort, Ashley L.; Prezant, David J.; Rom, William N.; Nolan, Anna

    2013-01-01

    Pulmonary vascular loss is an early feature of chronic obstructive pulmonary disease. Biomarkers of inflammation and of metabolic syndrome, predicts loss of lung function in World Trade Center Lung Injury (WTC-LI). We investigated if other cardiovascular disease (CVD) biomarkers also predicted WTC-LI. This nested case-cohort study used 801 never smoker, WTC exposed firefighters with normal pre-9/11 lung function presenting for subspecialty pulmonary evaluation (SPE) before March, 2008. A representative sub-cohort of 124/801 with serum drawn within six months of 9/11 defined CVD biomarker distribution. Post-9/11/01 FEV1 at subspecialty exam defined cases: susceptible WTC-LI cases with FEV1≤77% predicted (66/801) and resistant WTC-LI cases with FEV1≥107% (68/801). All models were adjusted for WTC exposure intensity, BMI at SPE, age at 9/11, and pre-9/11 FEV1. Susceptible WTC-LI cases had higher levels of Apo-AII, CRP, and MIP-4 with significant RRs of 3.85, 3.93, and 0.26 respectively with an area under the curve (AUC) of 0.858. Resistant WTC-LI cases had significantly higher sVCAM and lower MPO with RRs of 2.24, and 2.89 respectively; AUC 0.830. Biomarkers of CVD in serum six-month post-9/11 predicted either susceptibility or resistance to WTC-LI. These biomarkers may define pathways producing or protecting subjects from pulmonary vascular disease and associated loss of lung function after an irritant exposure. PMID:22903969

  13. Does Suspected Sleep Disordered Breathing Impact on the Sleep and Performance of Firefighting Volunteers during a Simulated Fire Ground Campaign?

    Directory of Open Access Journals (Sweden)

    Sarah M. Jay

    2016-01-01

    Full Text Available Adequate sleep is fundamental to workplace performance. For volunteer firefighters who work in safety critical roles, poor performance at work can be life threatening. Extended shifts and sleeping conditions negatively impact sleep during multi-day fire suppression campaigns. Having sleep disordered breathing (SDB could contribute further to sleep deficits. Our aim was to investigate whether those with suspected SDB slept and performed more poorly during a fire ground simulation involving sleep restriction. Participants, n = 20 participated in a 3-day-4-night fire ground simulation. Based on oximetry desaturation index data collected during their participation, participants were retrospectively allocated to either a SDB (n = 8 or a non-SDB group (n = 12. The simulation began with an 8 h Baseline sleep (BL followed by two nights of restricted (4 h sleep and an 8 h recovery sleep (R. All sleeps were recorded using a standard electroencephalography (EEG montage as well as oxygen saturation. During the day, participants completed neurobehavioral (response time, lapses and subjective fatigue tasks. Mixed effects ANOVA were used to compare differences in sleep and wake variables. Analyses revealed a main effect of group for Total sleep (TST, REM , wake after sleep onset (WASO and Arousals/h with the SDB group obtaining less TST and REM and greater WASO and Arousals/h. The group × night interaction was significant for N3 with the SDB group obtaining 42 min less during BL. There was a significant main effect of day for RRT, lapses and subjective fatigue and a significant day × group interaction for RRT. Overall, the SDB group slept less, experienced more disturbed sleep and had poorer response time performance, which was exacerbated by the second night of sleep restriction. This could present a safety concern, particularly during longer campaigns and is worthy of further investigation. In addition, we would recommend promotion of awareness of SDB, its

  14. Use of the bootstrap method to develop a physical fitness test for public safety officers who serve as both police officers and firefighters.

    Science.gov (United States)

    Adams, Jenny; Cheng, Dunlei; Lee, John; Shock, Tiffany; Kennedy, Kathleen; Pate, Scotty

    2014-07-01

    Physical fitness testing is a common tool for motivating employees with strenuous occupations to reach and maintain a minimum level of fitness. Nevertheless, the use of such tests can be hampered by several factors, including required compliance with US antidiscrimination laws. The Highland Park (Texas) Department of Public Safety implemented testing in 1991, but no single test adequately evaluated its sworn employees, who are cross-trained and serve as police officers and firefighters. In 2010, the department's fitness experts worked with exercise physiologists from Baylor Heart and Vascular Hospital to develop and evaluate a single test that would be equitable regardless of race/ethnicity, disability, sex, or age >50 years. The new test comprised a series of exercises to assess overall fitness, followed by two sequences of job-specific tasks related to firefighting and police work, respectively. The study group of 50 public safety officers took the test; raw data (e.g., the number of repetitions performed or the time required to complete a task) were collected during three quarterly testing sessions. The statistical bootstrap method was then used to determine the levels of performance that would correlate with 0, 1, 2, or 3 points for each task. A sensitivity analysis was done to determine the overall minimum passing score of 17 points. The new physical fitness test and scoring system have been incorporated into the department's policies and procedures as part of the town's overall employee fitness program.

  15. Novel fluorinated surfactants tentatively identified in firefighters using liquid chromatography quadrupole time-of-flight tandem mass spectrometry and a case-control approach.

    Science.gov (United States)

    Rotander, Anna; Kärrman, Anna; Toms, Leisa-Maree L; Kay, Margaret; Mueller, Jochen F; Gómez Ramos, María José

    2015-02-17

    Fluorinated surfactant-based aqueous film-forming foams (AFFFs) are made up of per- and polyfluorinated alkyl substances (PFAS) and are used to extinguish fires involving highly flammable liquids. The use of perfluorooctanesulfonic acid (PFOS) and other perfluoroalkyl acids (PFAAs) in some AFFF formulations has been linked to substantial environmental contamination. Recent studies have identified a large number of novel and infrequently reported fluorinated surfactants in different AFFF formulations. In this study, a strategy based on a case-control approach using quadrupole time-of-flight tandem mass spectrometry (QTOF-MS/MS) and advanced statistical methods has been used to extract and identify known and unknown PFAS in human serum associated with AFFF-exposed firefighters. Two target sulfonic acids [PFOS and perfluorohexanesulfonic acid (PFHxS)], three non-target acids [perfluoropentanesulfonic acid (PFPeS), perfluoroheptanesulfonic acid (PFHpS), and perfluorononanesulfonic acid (PFNS)], and four unknown sulfonic acids (Cl-PFOS, ketone-PFOS, ether-PFHxS, and Cl-PFHxS) were exclusively or significantly more frequently detected at higher levels in firefighters compared to controls. The application of this strategy has allowed for identification of previously unreported fluorinated chemicals in a timely and cost-efficient way.

  16. Physical employment standard for Canadian wildland firefighters: examining test-retest reliability and the impact of familiarisation and physical fitness training.

    Science.gov (United States)

    Gumieniak, Robert J; Gledhill, Norman; Jamnik, Veronica K

    2018-05-04

    To assess the impact of repeat performances (familiarisation) plus exercise training on completion time for the Ontario Wildland Firefighter (WFF) Fitness Test circuit (WFX-FIT), normally active general population participants (n = 145) were familiarised to the protocol then randomised into (i) exercise training, (ii) circuit only weekly performances or (iii) controls. At Baseline, the WFX-FIT pass rate for all groups combined was 11% for females and 73% for males, indicating that the Ontario WFX-FIT standard had a possible adverse impact on females. Following test familiarisation, mean circuit completion times improved by 11.9% and 10.2% for females and males, respectively. There were significant improvements in completion time for females (19.8%) and males (16.9%) who trained, plus females (12.2%) and males (9.8%) who performed the circuit only, while control participants were unchanged. Post training, the pass rate of the training group was 80% for females and 100% for males. Practitioner Summary: This paper details the impact of familiarisation plus exercise training as accommodation to mitigate potential adverse impact on initial attack wildland firefighter test performance. The results underscore the importance of test familiarisation opportunities and physical fitness training programmes that are specific to the demands of the job.

  17. An Analysis on the Moisture and Thermal Protective Performance of Firefighter Clothing Based on Different Layer Combinations and Effect of Washing on Heat Protection and Vapour Transfer Performance

    Directory of Open Access Journals (Sweden)

    Ozgur Atalay

    2015-01-01

    Full Text Available Fabric assemblies for firefighting clothing have been tested for heat protection and comfort. The constituent materials and fabric structures have been specifically selected and tailored for firefighters’ clothing. In order to do this, four types of outer shell fabrics, four types of moisture barrier fabrics, and four types of heat barriers with different weights and material compositions were used to make a multilayered fabric assembly. Heat transfer (flame, heat transfer (radiant, and water vapour resistance tests were conducted according to the latest EN469 test standard which also recommends washing tests. These tests reveal that material content and material brand have considerable effect on the required performance levels of heat protection. In addition, while washing tests have improved water vapor transfer properties, they have a deteriorating effect on heat protection performance. Considering heat protection and moisture comfort properties, the optimal assemblies are thereby identified.

  18. How Do Meaning in Life and Positive Affect Relate to Adaptation to Stress? The Case of Firefighters Following the Mount Carmel Forest Fire.

    Science.gov (United States)

    Shrira, Amit; Shmotkin, Dov; Palgi, Yuval; Soffer, Yechiel; Hamama Raz, Yaira; Tal-Katz, Patricia; Ben-Ezra, Menachem; Benight, Charles C

    2015-01-01

    We examined how positive affect (PA) and meaning in life (MIL) conjointly regulate posttraumatic stress disorder (PTSD) symptoms and perceived coping self-efficacy. Hypotheses were guided by a recent holistic model, according to which PA and MIL should compensate for each other in relating to adaptation to high stress. The sample included 75 Israeli firefighters who took active part in extinguishing the 2010 Mount Carmel forest fire. PA and MIL helped to compensate for the other, demonstrating that when one of them was low, the other related to higher adaptation. That is, under low MIL, PA related to PTSD symptoms and coping self-efficacy, and under low PA, MIL related to PTSD symptoms and coping self-efficacy. The study design was cross-sectional and therefore precluded any causal inferences. The findings lend additional support to the holistic model and help to understand how subjective well-being and MIL correlate with adaptation to stress.

  19. Aerobic Capacity, Physical Activity and Metabolic Risk Factors in Firefighters Compared with Police Officers and Sedentary Clerks.

    Science.gov (United States)

    Leischik, Roman; Foshag, Peter; Strauß, Markus; Littwitz, Henning; Garg, Pankaj; Dworrak, Birgit; Horlitz, Marc

    2015-01-01

    This study examined the association between the physical work environment and physiological performance measures, physical activity levels and metabolic parameters among German civil servants. A main focus in this study was to examine the group differences rather than measuring the absolute values in an occupational group. We prospectively examined 198 male German civil servants (97 firefighters [FFs], 55 police officers [POs] and 46 sedentary clerks [SCs]). For each parameter, the groups were compared using a linear regression adjusted for age. The 97 FFs showed a similar maximal aerobic power (VO2max l/min) of 3.17±0.44 l/min compared with the POs, who had a maximal aerobic power of 3.13±0.62 l/min (estimated difference, POs vs. FFs: 0.05, CI: -0.12-0.23, p=0.553). The maximal aerobic power of the FFs was slightly higher than that of the SCs, who had a maximal aerobic power of 2.85±0.52 l/min (-0.21, CI: -0.39-0.04, p=0.018 vs. FFs). The average physical activity (in metabolic equivalents [METS]/week) of the FFs was 3953±2688, whereas those of the POs was 2838±2872 (vs. FFs: -985, CI: -1941-30, p = 0.043) and of the SCs 2212±2293 (vs. FFs: -1598.8, CI: -2477-721, p = 0.000; vs. POs: -613.6, CI: -1617.4–390.3, p = 0.229), respectively [corrected]. For the FFs, the average body fat percentage was 17.7%±6.2, whereas it was 21.4%±5.6 for the POs (vs. FFs: 2.75, CI: 0.92-4.59, p=0.004) and 20.8%±6.5 for the SCs (vs. FFs: 1.98, CI: -0.28-4.25, p=0.086; vs. POs: -0.77, CI: 3.15-1.61, p=0.523). The average waist circumference was 89.8 cm±10.0 for the FFs, 97.8 cm±12.4 (5.63, CI: 2.10-9.15, p=0.002) for the POs, and 97.3±11.7 (vs. FFs: -4.89, CI: 1.24-8.55, p=0.009; vs. POs: -0.73, CI: -5.21-3.74, p=0.747) for the SCs. The FFs showed significantly higher physical activity levels compared with the SCs. The PO group had the highest cardiovascular risk of all of the groups because it included more participants with metabolic syndrome; furthermore, the POs had

  20. Aerobic Capacity, Physical Activity and Metabolic Risk Factors in Firefighters Compared with Police Officers and Sedentary Clerks.

    Directory of Open Access Journals (Sweden)

    Roman Leischik

    Full Text Available This study examined the association between the physical work environment and physiological performance measures, physical activity levels and metabolic parameters among German civil servants. A main focus in this study was to examine the group differences rather than measuring the absolute values in an occupational group.We prospectively examined 198 male German civil servants (97 firefighters [FFs], 55 police officers [POs] and 46 sedentary clerks [SCs]. For each parameter, the groups were compared using a linear regression adjusted for age.The 97 FFs showed a similar maximal aerobic power (VO2max l/min of 3.17±0.44 l/min compared with the POs, who had a maximal aerobic power of 3.13±0.62 l/min (estimated difference, POs vs. FFs: 0.05, CI: -0.12-0.23, p=0.553. The maximal aerobic power of the FFs was slightly higher than that of the SCs, who had a maximal aerobic power of 2.85±0.52 l/min (-0.21, CI: -0.39-0.04, p=0.018 vs. FFs. The average physical activity (in metabolic equivalents [METS]/week of the FFs was 3953±2688, whereas those of the POs was 2838±2872 (vs. FFs: -985, CI: -1941-30, p = 0.043 and of the SCs 2212±2293 (vs. FFs: -1598.8, CI: -2477-721, p = 0.000; vs. POs: -613.6, CI: -1617.4–390.3, p = 0.229, respectively [corrected]. For the FFs, the average body fat percentage was 17.7%±6.2, whereas it was 21.4%±5.6 for the POs (vs. FFs: 2.75, CI: 0.92-4.59, p=0.004 and 20.8%±6.5 for the SCs (vs. FFs: 1.98, CI: -0.28-4.25, p=0.086; vs. POs: -0.77, CI: 3.15-1.61, p=0.523. The average waist circumference was 89.8 cm±10.0 for the FFs, 97.8 cm±12.4 (5.63, CI: 2.10-9.15, p=0.002 for the POs, and 97.3±11.7 (vs. FFs: -4.89, CI: 1.24-8.55, p=0.009; vs. POs: -0.73, CI: -5.21-3.74, p=0.747 for the SCs.The FFs showed significantly higher physical activity levels compared with the SCs. The PO group had the highest cardiovascular risk of all of the groups because it included more participants with metabolic syndrome; furthermore, the POs

  1. Sorbent amendment as a remediation strategy to reduce PFAS mobility and leaching in a contaminated sandy soil from a Norwegian firefighting training facility.

    Science.gov (United States)

    Hale, Sarah E; Arp, Hans Peter H; Slinde, Gøril Aasen; Wade, Emma Jane; Bjørseth, Kamilla; Breedveld, Gijs D; Straith, Bengt Fredrik; Moe, Kamilla Grotthing; Jartun, Morten; Høisæter, Åse

    2017-03-01

    Aqueous film-forming foams (AFFF) containing poly- and perfluoroalkyl substances (PFAS) used for firefighting have led to the contamination of soil and water at training sites. The unique physicochemical properties of PFAS results in environmental persistency, threatening water quality and making remediation of such sites a necessity. This work investigated the role of sorbent amendment to PFAS contaminated soils in order to immobilise PFAS and reduce mobility and leaching to groundwater. Soil was sampled from a firefighting training facility at a Norwegian airport and total and leachable PFAS concentrations were quantified. Perfluorooctanesulfonic acid (PFOS) was the most dominant PFAS present in all soil samples (between 9 and 2600 μg/kg). Leaching was quantified using a one-step batch test with water (L/S 10). PFOS concentrations measured in leachate water ranged between 1.2 μg/L and 212 μg/L. Sorbent amendment (3%) was tested by adding activated carbon (AC), compost soil and montmorillonite to selected soils. The extent of immobilisation was quantified by measuring PFAS concentrations in leachate before and after amendment. Leaching was reduced between 94 and 99.9% for AC, between 29 and 34% for compost soil and between 28 and 40% for the montmorillonite amended samples. Sorbent + soil/water partitioning coefficients (K D ) were estimated following amendment and were around 8 L/kg for compost soil and montmorillonite amended soil and ranged from 1960 to 16,940 L/kg for AC amended soil. The remediation of AFFF impacted soil via immobilisation of PFAS following sorbent amendment with AC is promising as part of an overall remediation strategy. Copyright © 2016 Elsevier Ltd. All rights reserved.

  2. Does the knowledge-to-action (KTA) framework facilitate physical demands analysis development for firefighter injury management and return-to-work planning?

    Science.gov (United States)

    Sinden, Kathryn; MacDermid, Joy C

    2014-03-01

    Employers are tasked with developing injury management and return-to-work (RTW) programs in response to occupational health and safety policies. Physical demands analyses (PDAs) are the cornerstone of injury management and RTW development. Synthesizing and contextualizing policy knowledge for use in occupational program development, including PDAs, is challenging due to multiple stakeholder involvement. Few studies have used a knowledge translation theoretical framework to facilitate policy-based interventions in occupational contexts. The primary aim of this case study was to identify how constructs of the knowledge-to-action (KTA) framework were reflected in employer stakeholder-researcher collaborations during development of a firefighter PDA. Four stakeholder meetings were conducted with employee participants who had experience using PDAs in their occupational role. Directed content analysis informed analyses of meeting minutes, stakeholder views and personal reflections recorded throughout the case. Existing knowledge sources including local data, stakeholder experiences, policies and priorities were synthesized and tailored to develop a PDA in response to the barriers and facilitators identified by the firefighters. The flexibility of the KTA framework and synthesis of multiple knowledge sources were identified strengths. The KTA Action cycle was useful in directing the overall process but insufficient for directing the specific aspects of PDA development. Integration of specific PDA guidelines into the process provided explicit direction on best practices in tailoring the PDA and knowledge synthesis. Although the themes of the KTA framework were confirmed in our analysis, order modification of the KTA components was required. Despite a complex context with divergent perspectives successful implementation of a draft PDA was achieved. The KTA framework facilitated knowledge synthesis and PDA development but specific standards and modifications to the KTA

  3. High capacity hydrogen storage nanocomposite materials

    Science.gov (United States)

    Zidan, Ragaiy; Wellons, Matthew S.

    2017-12-12

    A novel hydrogen absorption material is provided comprising a mixture of a lithium hydride with a fullerene. The subsequent reaction product provides for a hydrogen storage material which reversibly stores and releases hydrogen at temperatures of about 270.degree. C.

  4. High capacity carrier ethernet transport networks

    DEFF Research Database (Denmark)

    Rasmussen, Anders; Zhang, Jiang; Yu, Hao

    2009-01-01

    OAM functions, survivability and the increased bandwidth requirements of carrier class systems. This article provides an overview of PBB-TE and T-MPLS and demonstrates how IPTV services can be realized in the framework of Carrier Ethernet. In addition we provide a case study on performing bit error...

  5. A high capacity FASTBUS multiple event buffer

    International Nuclear Information System (INIS)

    Appel, J.A.; Farr, W.D.; Kaplan, D.M.; Levit, L.B.; Napier, T.M.

    1985-01-01

    We have developed a front-end data acquisition and event buffering memory. This single-width FASTBUS module has a capacity of 256K X 32 bits plus parity. The module is dual ported, and its front panel ECLport accepts data at up to 20 MB/sec. It may also be written to and read from as a standard FASTBUS Slave. The module records events as variable length records. Each record is accepted or rejected via front panel control signal. Circuitry to automate FASTBUS record readout and record skip is provided. In its ''linear'' mode, the module may be used as a single pass list. Alternatively, in the ''circular'' mode, the module's internal read pointer can follow its write pointer continuously around the memory. Circular mode is well suited to handling of a continuous data stream. Modules may be linked for larger memory capacity

  6. Designs of new plants of high capacity

    International Nuclear Information System (INIS)

    Borges R, Diego A

    1999-01-01

    The Caracas electricity in their desire to lend the best service to the community is doing the necessary projects of generation expansion to fulfill and requirements of demand of next decade in to the metropolitan area. The projects of the new plants of Recifes and El Sitio, have been conceptualized in way of executing the engineering and patterns construction of highest quality and once setting in service, to reach the highest indexes of operative. To reach these goals it is planned to use the most advanced technological designs that are in the market at the moment to world in generation and transmission of power

  7. The mediation effect of PTSD, perceived job stress and resilience on the relationship between trauma exposure and the development of depression and alcohol use problems in Korean firefighters: A cross-sectional study.

    Science.gov (United States)

    Kim, Johanna Inhyang; Park, Heyeon; Kim, Jeong-Hyun

    2018-03-15

    Firefighters constitute a high-risk group for depression and alcohol use disorders (AUDs) due to frequent exposure to trauma. Perceived job stress and resilience are powerful factors affecting the occurrence of depression and AUDs; however, research on this subject is scarce. We investigated the relationship of perceived job stress and resilience with depression or AUDs in firefighters. A total of 7151 Korean firefighters were included for analysis. Participants completed self-report scales, including a self-reported number of exposure to incident stressors, the Korean Occupational Stress Scale - Short Form, the Post-traumatic Stress Disorder (PTSD) Symptoms Checklist - Civilian version, the Patient Health Questionnaire 9, the Brief Resilience Scale, and the Alcohol Use Disorders Identification Test. Hierarchical multivariable linear regression analyses were performed to identify the relationship of perceived job stress and resilience with depression or AUDs. Path analyses were applied to investigate the mediation effects of PTSD, perceived job stress and resilience between trauma exposure and depression or AUDs. There were significant associations of perceived job stress and resilience with depression and AUDs, respectively, even after adjusting for demographic factors, number of traumatic events, and PTSD symptoms. The relationship between trauma exposure and depression/AUDs was mediated by PTSD symptoms, which had both direct and indirect effects on depression and AUDs; indirect effect was mediated by job stress and resilience. The findings in this study demonstrated that PTSD, perceived job stress and resilience can mediate the development of depression or AUDs following trauma exposure in firefighters. Efforts to prevent PTSD, reduce job stress and increase individual resilience could help prevent depression and AUDs. The cross-sectional study design and self-report nature of the assessment tools limit the current findings. Copyright © 2018 Elsevier B.V. All

  8. Safety profile, efficacy, and biodistribution of a bicistronic high-capacity adenovirus vector encoding a combined immunostimulation and cytotoxic gene therapy as a prelude to a phase I clinical trial for glioblastoma

    Energy Technology Data Exchange (ETDEWEB)

    Puntel, Mariana [Department of Neurosurgery, The University of Michigan School of Medicine, MSRB II, RM 4570C, 1150 West Medical Center Drive, Ann Arbor, MI 48109-5689 (United States); Department of Cell and Developmental Biology, The University of Michigan School of Medicine, MSRB II, RM 4570C, 1150 West Medical Center Drive, Ann Arbor, MI 48109-5689 (United States); Gene Therapeutics Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048 (United States); Ghulam, Muhammad A.K.M. [Gene Therapeutics Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048 (United States); Farrokhi, Catherine [Department of Psychiatry and Behavioral Neurosciences, Cedars Sinai Medical Center, Los Angeles, CA 90048 (United States); VanderVeen, Nathan; Paran, Christopher; Appelhans, Ashley [Department of Neurosurgery, The University of Michigan School of Medicine, MSRB II, RM 4570C, 1150 West Medical Center Drive, Ann Arbor, MI 48109-5689 (United States); Department of Cell and Developmental Biology, The University of Michigan School of Medicine, MSRB II, RM 4570C, 1150 West Medical Center Drive, Ann Arbor, MI 48109-5689 (United States); Kroeger, Kurt M.; Salem, Alireza [Gene Therapeutics Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048 (United States); Lacayo, Liliana [Department of Psychiatry and Behavioral Neurosciences, Cedars Sinai Medical Center, Los Angeles, CA 90048 (United States); Pechnick, Robert N. [Department of Psychiatry and Behavioral Neurosciences, Cedars Sinai Medical Center, Los Angeles, CA 90048 (United States); Department of Psychiatry and Behavioral Neurosciences, David Geffen School of Medicine, University of California, Los Angeles, CA (United States); Kelson, Kyle R.; Kaur, Sukhpreet; Kennedy, Sean [Gene Therapeutics Research Institute, Cedars-Sinai Medical Center, Los Angeles, CA 90048 (United States); Palmer, Donna; Ng, Philip [Department of Molecular and Human Genetics, Baylor College of Medicine, Houston, TX 77030 (United States); and others

    2013-05-01

    Adenoviral vectors (Ads) are promising gene delivery vehicles due to their high transduction efficiency; however, their clinical usefulness has been hampered by their immunogenicity and the presence of anti-Ad immunity in humans. We reported the efficacy of a gene therapy approach for glioma consisting of intratumoral injection of Ads encoding conditionally cytotoxic herpes simplex type 1 thymidine kinase (Ad-TK) and the immunostimulatory cytokine fms-like tyrosine kinase ligand 3 (Ad-Flt3L). Herein, we report the biodistribution, efficacy, and neurological and systemic effects of a bicistronic high-capacity Ad, i.e., HC-Ad-TK/TetOn-Flt3L. HC-Ads elicit sustained transgene expression, even in the presence of anti-Ad immunity, and can encode large therapeutic cassettes, including regulatory elements to enable turning gene expression “on” or “off” according to clinical need. The inclusion of two therapeutic transgenes within a single vector enables a reduction of the total vector load without adversely impacting efficacy. Because clinically the vectors will be delivered into the surgical cavity, normal regions of the brain parenchyma are likely to be transduced. Thus, we assessed any potential toxicities elicited by escalating doses of HC-Ad-TK/TetOn-Flt3L (1 × 10{sup 8}, 1 × 10{sup 9}, or 1 × 10{sup 10} viral particles [vp]) delivered into the rat brain parenchyma. We assessed neuropathology, biodistribution, transgene expression, systemic toxicity, and behavioral impact at acute and chronic time points. The results indicate that doses up to 1 × 10{sup 9} vp of HC-Ad-TK/TetOn-Flt3L can be safely delivered into the normal rat brain and underpin further developments for its implementation in a phase I clinical trial for glioma. - Highlights: ► High capacity Ad vectors elicit sustained therapeutic gene expression in the brain. ► HC-Ad-TK/TetOn-Flt3L encodes two therapeutic genes and a transcriptional switch. ► We performed a dose escalation study at

  9. Effects of fire and three fire-fighting chemicals on main soil properties, plant nutrient content and vegetation growth and cover after 10 years

    Energy Technology Data Exchange (ETDEWEB)

    Fernández-Fernández, M., E-mail: mariafernandez@iiag.csic.es; Gómez-Rey, M.X., E-mail: mxgomez@iiag.csic.es; González-Prieto, S.J., E-mail: serafin@iiag.csic.es

    2015-05-15

    The study addresses a knowledge-gap in the long-term ecological consequences of fire and fire-fighting chemicals. Ten years after a prescribed fire and the application of three fire-fighting chemicals, their effects on the soil–plant system were evaluated. Five treatments were established: unburnt soils (US) and burnt soils treated with water alone (BS), foaming agent (BS + Fo), Firesorb (BS + Fi) and ammonium polyphosphate (BS + Ap). Soils (0–2 cm depth) and foliar material of shrubs (Erica umbellata, Pterospartum tridentatum and Ulex micranthus) and trees (Pinus pinaster) were analysed for total N, δ{sup 15}N, and soil-available and plant total macronutrients and trace elements. Soil pH, NH{sub 4}{sup +}–N and NO{sub 3}{sup −}–N; pine basal diameter and height; and shrub cover and height were also measured. Compared with US plots, burnt soils had less nitrates and more Mo. Although differences were not always significant, BS + Ap had the highest levels of soil available P, Na and Al. Plants from BS + Ap plots had higher values of δ{sup 15}N (P. pinaster and E. umbellata), P (all species), Na (P. tridentatum and U. micranthus) and Mg (E. umbellata and P. tridentatum) than other treatments; while K in plants from BS + Ap plots was the highest among treatments for P. pinaster and the lowest for the shrubs. Pines in US plots were higher and wider than in burnt treatments, except for BS + Ap, where the tallest and widest trees were found, although half of them were either dead (the second highest mortality after BS + Fi) or had a distorted trunk. BS + Ap was the treatment with strongest effects on plants, showing E. umbellata the lowest coverage and height, P. tridentatum the highest coverage, U. micranthus one of the lowest coverages and being the only treatment where Genista triacanthos was absent. Consequently, it is concluded that both fire and ammonium polyphosphate application had significant effects on the soil–plant system after 10 years

  10. Effects of fire and three fire-fighting chemicals on main soil properties, plant nutrient content and vegetation growth and cover after 10 years

    International Nuclear Information System (INIS)

    Fernández-Fernández, M.; Gómez-Rey, M.X.; González-Prieto, S.J.

    2015-01-01

    The study addresses a knowledge-gap in the long-term ecological consequences of fire and fire-fighting chemicals. Ten years after a prescribed fire and the application of three fire-fighting chemicals, their effects on the soil–plant system were evaluated. Five treatments were established: unburnt soils (US) and burnt soils treated with water alone (BS), foaming agent (BS + Fo), Firesorb (BS + Fi) and ammonium polyphosphate (BS + Ap). Soils (0–2 cm depth) and foliar material of shrubs (Erica umbellata, Pterospartum tridentatum and Ulex micranthus) and trees (Pinus pinaster) were analysed for total N, δ 15 N, and soil-available and plant total macronutrients and trace elements. Soil pH, NH 4 + –N and NO 3 − –N; pine basal diameter and height; and shrub cover and height were also measured. Compared with US plots, burnt soils had less nitrates and more Mo. Although differences were not always significant, BS + Ap had the highest levels of soil available P, Na and Al. Plants from BS + Ap plots had higher values of δ 15 N (P. pinaster and E. umbellata), P (all species), Na (P. tridentatum and U. micranthus) and Mg (E. umbellata and P. tridentatum) than other treatments; while K in plants from BS + Ap plots was the highest among treatments for P. pinaster and the lowest for the shrubs. Pines in US plots were higher and wider than in burnt treatments, except for BS + Ap, where the tallest and widest trees were found, although half of them were either dead (the second highest mortality after BS + Fi) or had a distorted trunk. BS + Ap was the treatment with strongest effects on plants, showing E. umbellata the lowest coverage and height, P. tridentatum the highest coverage, U. micranthus one of the lowest coverages and being the only treatment where Genista triacanthos was absent. Consequently, it is concluded that both fire and ammonium polyphosphate application had significant effects on the soil–plant system after 10 years. - Highlights: • We hypothesized

  11. Effects of fire and three fire-fighting chemicals on main soil properties, plant nutrient content and vegetation growth and cover after 10 years.

    Science.gov (United States)

    Fernández-Fernández, M; Gómez-Rey, M X; González-Prieto, S J

    2015-05-15

    The study addresses a knowledge-gap in the long-term ecological consequences of fire and fire-fighting chemicals. Ten years after a prescribed fire and the application of three fire-fighting chemicals, their effects on the soil-plant system were evaluated. Five treatments were established: unburnt soils (US) and burnt soils treated with water alone (BS), foaming agent (BS+Fo), Firesorb (BS+Fi) and ammonium polyphosphate (BS+Ap). Soils (0-2 cm depth) and foliar material of shrubs (Erica umbellata, Pterospartum tridentatum and Ulex micranthus) and trees (Pinus pinaster) were analysed for total N, δ(15)N, and soil-available and plant total macronutrients and trace elements. Soil pH, NH₄(+)-N and NO₃(-)-N; pine basal diameter and height; and shrub cover and height were also measured. Compared with US plots, burnt soils had less nitrates and more Mo. Although differences were not always significant, BS+Ap had the highest levels of soil available P, Na and Al. Plants from BS+Ap plots had higher values of δ(15)N (P. pinaster and E. umbellata), P (all species), Na (P. tridentatum and U. micranthus) and Mg (E. umbellata and P. tridentatum) than other treatments; while K in plants from BS+Ap plots was the highest among treatments for P. pinaster and the lowest for the shrubs. Pines in US plots were higher and wider than in burnt treatments, except for BS+Ap, where the tallest and widest trees were found, although half of them were either dead (the second highest mortality after BS+Fi) or had a distorted trunk. BS+Ap was the treatment with strongest effects on plants, showing E. umbellata the lowest coverage and height, P. tridentatum the highest coverage, U. micranthus one of the lowest coverages and being the only treatment where Genista triacanthos was absent. Consequently, it is concluded that both fire and ammonium polyphosphate application had significant effects on the soil-plant system after 10 years. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. High-Affinity Low-Capacity and Low-Affinity High-Capacity N-Acetyl-2-Aminofluorene (AAF) Macromolecular Binding Sites Are Revealed During the Growth Cycle of Adult Rat Hepatocytes in Primary Culture.

    Science.gov (United States)

    Koch, Katherine S; Moran, Tom; Shier, W Thomas; Leffert, Hyam L

    2018-05-01

    Long-term cultures of primary adult rat hepatocytes were used to study the effects of N-acetyl-2-aminofluorene (AAF) on hepatocyte proliferation during the growth cycle; on the initiation of hepatocyte DNA synthesis in quiescent cultures; and, on hepatocyte DNA replication following the initiation of DNA synthesis. Scatchard analyses were used to identify the pharmacologic properties of radiolabeled AAF metabolite binding to hepatocyte macromolecules. Two classes of growth cycle-dependent AAF metabolite binding sites-a high-affinity low-capacity site (designated Site I) and a low-affinity high-capacity site (designated Site II)-associated with two spatially distinct classes of macromolecular targets, were revealed. Based upon radiolabeled AAF metabolite binding to purified hepatocyte genomic DNA or to DNA, RNA, proteins, and lipids from isolated nuclei, Site IDAY 4 targets (KD[APPARENT] ≈ 2-4×10-6 M and BMAX[APPARENT] ≈ 6 pmol/106 cells/24 h) were consistent with genomic DNA; and with AAF metabolized by a nuclear cytochrome P450. Based upon radiolabeled AAF binding to total cellular lysates, Site IIDAY 4 targets (KD[APPARENT] ≈ 1.5×10-3 M and BMAX[APPARENT] ≈ 350 pmol/106 cells/24 h) were consistent with cytoplasmic proteins; and with AAF metabolized by cytoplasmic cytochrome P450s. DNA synthesis was not inhibited by concentrations of AAF that saturated DNA binding in the neighborhood of the Site I KD. Instead, hepatocyte DNA synthesis inhibition required higher concentrations of AAF approaching the Site II KD. These observations raise the possibility that carcinogenic DNA adducts derived from AAF metabolites form below concentrations of AAF that inhibit replicative and repair DNA synthesis.

  13. Systems for the calculation of electrical parameters and energy efficiency for high-capacity hydroelectric generators; Sistemas para el calculo de parametros electricos y eficiencia energetica para generadores hidroelectricos de gran capacidad

    Energy Technology Data Exchange (ETDEWEB)

    Reyes Martinez, Oscar Alfonso; Pascacio de los Santos, Alberth; Perez Abad, Carlos Alberto [Instituto de Investigaciones Electricas, Cuernavaca, Morelos (Mexico); Leon Rivera, Nicolas [CFE-LAPEM, Irapuato, Guanajuato (Mexico)

    2012-07-01

    In recent years, the Comision Federal de Electricidad (CFE) has developed important hydroelectrical power projects in Mexico. Most of them are located in the Santiago River Hydrological System in Nayarit, Mexico. A total of 27 projects with a capacity of 4,300 MW are considered but only 32% of them have been carried out. One of the most ambitious projects that continue in process of construction is the Hydroelectrical Plant La Yesca. This project will conclude in late 2012 and consists of two electric generators of 375 MW, 17 kV. It will be second in power and the third in electrical generation at the system. According to national and international standards, a set of static and dynamic tests must be performed in these generators before commissioning, to ensure their proper operation. Winding stator high voltage endurance test, three phase sudden short circuit test and energy efficiency calculation are some of the most important tests to be performed in a new electrical generator. These tests are difficult to perform on-site due to the equipment capacity required, so very few companies in the world can conduct them. In Mexico no one has the necessary infrastructure for testing in high capacity hydroelectric generators such as those from La Yesca, so the Laboratorio de Pruebas a Equipos y Materiales (LAPEM) has invested in projects to improve this project in order to meet the needs of the Mexican electricity sector. This paper is a description of the systems developed for the calculation of electrical parameters and energy efficiency for this class of generators. [Spanish] En los ultimos anos, la Comision Federal de Electricidad (CFE) ha desarrollado importantes proyectos hidroelectricos en Mexico. La mayor parte se ubican en el Sistema Hidrologico del Rio Santiago en Nayarit, Mexico. Se consideran un total de 27 proyectos con capacidad de 4300 MW, pero solo 32 % de ellos se han llevado a cabo. Uno de los proyectos mas ambiciosos que continua en proceso de

  14. Pulmonary function in portuguese firefighters

    OpenAIRE

    Almeida, A G; Duarte, R; Mieiro, L; Paiva, C; Rodrigues, A M; Almeida, M H; Bárbara, C

    2007-01-01

    Introdução: Nos últimos anos, Portugal tem sido afectado por muitos incêndios florestais. O fumo produzido pela combustão de material orgânico é responsável por efeitos a curto e longo prazo na função respiratória de indivíduos expostos. Objectivo: Caracterizar a função respiratória de bombeiros voluntários portugueses no activo expostos a fumo de incêndio florestal. Métodos: Estudo descritivo transversal. Aplicou-se um questionário individual sobre hábitos pessoais e ocupacionais e mediram-s...

  15. Firefighter Safety for PV Systems

    DEFF Research Database (Denmark)

    Mathe, Laszlo; Sera, Dezso; Spataru, Sergiu

    2015-01-01

    An important and highly discussed safety issue for photovoltaic (PV) systems is that as long as the PV panels are illuminated, a high voltage is present at the PV string terminals and cables between the string and inverters that is independent of the state of the inverter's dc disconnection switch...

  16. High-Capacity Short-Range Optical Communication Links

    DEFF Research Database (Denmark)

    Tatarczak, Anna

    Over the last decade, we have observed a tremendous spread of end-user mobile devices. The user base of a mobile application can grow or shrink by millions per day. This situation creates a pressing need for highly scalable server infrastructure; a need nowadays satisfied through cloud computing...... offered by data centers. As the popularity of cloud computing soars, the demand for high-speed, short-range data center links grows. Vertical cavity surface emitting lasers (VCSEL) and multimode fibers (MMF) prove especially well-suited for such scenarios. VCSELs have high modulation bandwidths......, we achieve 10 Gbps over 400 m and then conrm the approach in an optimized system at 25 Gbps over 300 m. The techniques described in this thesis leverage additional degrees of freedom to better utilize the available resources of short-range links. The proposed schemes enable higher speeds and longer...

  17. High-Capacity Transmission Using High-Density Multicore Fiber

    DEFF Research Database (Denmark)

    Morioka, Toshio

    2017-01-01

    There have been intense research activities on SDM technologies including SDM fibers, MC-, MM-amplifiers, DEMUXs/DEMUXs with record-breaking transmission demonstrations up to 2 Pbit/s. 100 (20 dB) SDM gain, i.e. 10 Pbit/s per fiber will be a short-term goal in order for the new fibers to be consi......There have been intense research activities on SDM technologies including SDM fibers, MC-, MM-amplifiers, DEMUXs/DEMUXs with record-breaking transmission demonstrations up to 2 Pbit/s. 100 (20 dB) SDM gain, i.e. 10 Pbit/s per fiber will be a short-term goal in order for the new fibers...... to be considered for installation in the future systems although the far long term demand should be transporting 1 Ebit/s per fiber over 1000 km meaning Zbit/s-km. Cost effective network capability such as ADM and XC should also be investigated based on the new SDM schemes. In the 10-20 years time frame, we need...

  18. High Capacity Anodes for Advanced Lithium Ion Batteries, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Lithium-ion batteries are slowly being introduced into satellite power systems, but their life still presents concerns for longer duration missions. Future NASA...

  19. Progress in development of high capacity magnetic HTS bearings

    International Nuclear Information System (INIS)

    Kummeth, P.; Nick, W.; Neumueller, H.-W.

    2005-01-01

    HTS magnetic bearings are inherently stable without an active feedback system. They provide low frictional losses, no wear and allow operation at high rotational speed without lubrication. So they are very promising for use in motors, generators and turbines. We designed and constructed an HTS radial bearing for use with a 400 kW HTS motor. It consists of alternating axially magnetized permanent magnet rings on the rotor and a segmented YBCO stator. Stator cooling is performed by liquid nitrogen, the temperature of the stator can be adjusted by varying the pressure in the cryogenic vessel. At 68 K maximum radial forces of more than 3.7 kN were found. These results range within the highest radial bearing capacities reported worldwide. The encouraging results lead us to develop a large heavy load HTS radial bearing. Currently a high magnetic gradient HTS bearing for a 4 MVA synchronous HTS generator is under construction

  20. Battery designs with high capacity anode materials and cathode materials

    Energy Technology Data Exchange (ETDEWEB)

    Masarapu, Charan; Anguchamy, Yogesh Kumar; Han, Yongbong; Deng, Haixia; Kumar, Sujeet; Lopez, Herman A.

    2017-10-03

    Improved high energy capacity designs for lithium ion batteries are described that take advantage of the properties of high specific capacity anode active compositions and high specific capacity cathode active compositions. In particular, specific electrode designs provide for achieving very high energy densities. Furthermore, the complex behavior of the active materials is used advantageously in a radical electrode balancing design that significantly reduced wasted electrode capacity in either electrode when cycling under realistic conditions of moderate to high discharge rates and/or over a reduced depth of discharge.

  1. Edge-riched graphene nanoribbon for high capacity electrode materials

    International Nuclear Information System (INIS)

    Ping, Yunjie; Zhang, Yupeng; Gong, Youning; Cao, Bing; Fu, Qiang; Pan, Chunxu

    2017-01-01

    Highlights: •The graphene nanoribbon has been successfully synthesized by longitudinal unzipping of carbon nanotubes with oxidants KMnO 4 . •Compared with graphene oxide and carbon nanotubes, graphene nanoribbon shows the largest capacitance up to ∼202F/g at a scan rate of 5 mV/s. •The importance of the location of functional groups and the importance of the edge structure. •The pseudo-capacitance material should have high electron transfer and rapid ion diffusion. -- Abstract: Carbon materials have attracted great attention for their diversified applications in supercapacitors, and different structures of carbon have been reported to exhibit dissimilar electrochemical properties. In the past, activated carbons, carbon nanotubes (CNTs), carbon nanofibers and graphene have been shown to have excellent electrochemical performances, but it still remains a problem on how to improve the capacitance of carbon-based materials effectively from the viewpoint of their giant commercial potential. Noticing that connecting chemical groups to carbon can provide large pseudo-capacitance, we hereby demonstrated that the position of the chemical groups also plays an important role in the pseudo-capacitance. In our work, we synthesized graphene nanoribbon (GNR), graphene oxide (GO) and functional MWCNTs and showed that GNR has larger capacitance (calculated to be 202 F/g at a scan rate of 5 mV/s) and energy density compared to CNTs and GO when using as electrode materials. Furthermore, the supercapacitor device based on as-synthesized GNR exhibits excellent cycle stability and rate capability which evident is potential in high performance supercapacitor. Revealing the source of the capacitance, we found that though GNR has less oxygen-containing groups, it has larger pseudo-capacitance than GO and CNTs due to the remarkable edge-riched structure with high activity in electrochemical reactions. This finding highlights the importance of edge structure in carbon-based pseudo supercapacitor and suggests a new insight for the development of pseudo-capacitance electrode materials.

  2. Ultra-High Capacity Silicon Photonic Interconnects through Spatial Multiplexing

    Science.gov (United States)

    Chen, Christine P.

    The market for higher data rate communication is driving the semiconductor industry to develop new techniques of writing at smaller scales, while continuing to scale bandwidth at low power consumption. Silicon photonic (SiPh) devices offer a potential solution to the electronic interconnect bandwidth bottleneck. SiPh leverages the technology commensurate of decades of fabrication development with the unique functionality of next-generation optical interconnects. Finer fabrication techniques have allowed for manufacturing physical characteristics of waveguide structures that can support multiple modes in a single waveguide. By refining modal characteristics in photonic waveguide structures, through mode multiplexing with the asymmetric y-junction and microring resonator, higher aggregate data bandwidth is demonstrated via various combinations of spatial multiplexing, broadening applications supported by the integrated platform. The main contributions of this dissertation are summarized as follows. Experimental demonstrations of new forms of spatial multiplexing combined together exhibit feasibility of data transmission through mode-division multiplexing (MDM), mode-division and wavelength-division multiplexing (MDM-WDM), and mode-division and polarization-division multiplexing (MDM-PDM) through a C-band, Si photonic platform. Error-free operation through mode multiplexers and demultiplexers show how data can be viably scaled on multiple modes and with existing spatial domains simultaneously. Furthermore, we explore expanding device channel support from two to three arms. Finding that a slight mismatch in the third arm can increase crosstalk contributions considerably, especially when increasing data rate, we explore a methodical way to design the asymmetric y-junction device by considering its angles and multiplexer/demultiplexer arm width. By taking into consideration device fabrication variations, we turn towards optimizing device performance post-fabrication. Through ModePROP simulations, optimizing device performance dynamically post-fabrication is analyzed, through either electro-optical or thermo-optical means. By biasing the arm introducing the slight spectral offset, we can quantifiably improve device performance. Scaling bandwidth is experimentally demonstrated through the device at 3 modes, 2 wavelengths, and 40 Gb/s data rate for 240 Gb/s aggregate bandwidth, with the potential to reduce power penalty per the device optimization process we described. A main motivation for this on-chip spatial multiplexing is the need to reduce costs. As the laser source serves as the greatest power consumer in an optical system, mode-division multiplexing and other forms of spatial multiplexing can be implemented to push its potentially prohibitive cost metrics down. In order to demonstrate an intelligent platform capable of dynamically multicasting data and reallocating power as needed by the system, we must first initialize the switch fabric to control with an electronic interface. A dithering mechanism, whereby exact cross, bar, and sub-percentage states are enforced through the device, is described here. Such a method could be employed for actuating the device table of bias values to states automatically. We then employ a dynamic power reallocation algorithm through a data acquisition unit, showing real-time channel recovery for channels experiencing power loss by diverting power from paths that could tolerate it. The data that is being multicast through the system is experimentally shown to be error-free at 40 Gb/s data rate, when transmitting from one to three clients and going from automatic bar/cross states to equalized power distribution. For the last portion of this topic, the switch fabric was inserted into a high-performance computing system. In order to run benchmarks at 10 Gb/s data ontop of the switch fabric, a newer model of the control plane was implemented to toggle states according to the command issued by the server. Such a programmable mechanism will prove necessary in future implementations of optical subsystems embedded inside larger systems, like data centers. Beyond the specific control plane demonstrated, the idea of an intelligent photonic layer can be applied to alleviate many kinds of optical channel abnormalities or accommodate for switching based on different patterns in data transmission. Finally, the experimental demonstration of a coherent perfect absorption Si modulator is exhibited, showing a viable extinction ratio of 24.5 dB. Using this coherent perfect absorption mechanism to demodulate signals, there is the added benefit of differential reception. Currently, an automated process for data collection is employed at a faster time scale than instabilities present in fibers in the setup with future implementations eliminating the off-chip phase modulator for greater signal stability. The field of SiPh has developed to a stage where specific application domains can take off and compete according to industrial-level standards. The work in this dissertation contributes to experimental demonstration of a newly developing area of mode-division multiplexing for substantially increasing bandwidth on-chip. While implementing the discussed photonic devices in dynamic systems, various attributes of integrated photonics are leveraged with existing electronic technologies. Future generations of computing systems should then be designed by implementing both system and device level considerations. (Abstract shortened by ProQuest.).

  3. Burnup credit applications in a high-capacity truck cask

    International Nuclear Information System (INIS)

    Boshoven, J.K.

    1992-09-01

    General Atomics (GA) has designed two legal weight truck (LWT) casks, the GA-4 and GA-9, to carry four pressurized-water-reactor (PWR) and nine boiling-water-reactor (BWR) fuel assemblies, respectively. GA plans to submit applications for certification to the US Nuclear Regulatory Commission (NRC) for the two casks in mid-1993. GA will include burnup credit analysis in the Safety Analysis Report for Packaging (SARP) for the GA-4 Cask. By including burnup credit in the criticality safety analysis for PWR fuels with initial enrichments above 3% U-235, public and occupation risks are reduced and cost savings are realized. The GA approach to burnup credit analysis incorporates the information produced in the US Department of Energy Burnup Credit Program. This paper describes the application of burnup credit to the criticality control design of the GA-4 Cask

  4. Porous graphene for high capacity lithium ion battery anode material

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Yusheng, E-mail: xxwysheng@163.com [College of Mathematics and Information Science, North China University of Water Resources and Electric Power, Zhengzhou 450011 (China); School of Physics and Engineering, Zhengzhou University, Zhengzhou 450001 (China); Zhang, Qiaoli; Jia, Min; Yang, Dapeng [College of Mathematics and Information Science, North China University of Water Resources and Electric Power, Zhengzhou 450011 (China); Wang, Jianjun; Li, Meng [College of Science, Zhongyuan University of Technology, Zhengzhou 450007 (China); Zhang, Jing [College of Mathematics and Information Science, North China University of Water Resources and Electric Power, Zhengzhou 450011 (China); Sun, Qiang [School of Physics and Engineering, Zhengzhou University, Zhengzhou 450001 (China); Jia, Yu, E-mail: jiayu@zzu.edu.cn [School of Physics and Engineering, Zhengzhou University, Zhengzhou 450001 (China)

    2016-02-15

    Graphical abstract: - Highlights: • Porous graphene sheet as Li storage media. • Excellent mobility both along in-plane and out-plane directions. • The interactions can be easily tuned by an applied strain. - Abstract: Based on density functional theory calculations, we studied the Li dispersed on porous graphene (PG) for its application as Li ion battery anode material. The hybridization of Li atoms and the carbon atoms enhanced the interaction between Li atoms and the PG. With holes of specific size, the PG can provide excellent mobility with moderate barriers of 0.37–0.39 eV. The highest Li storage composite can be LiC{sub 0.75}H{sub 0.38} which corresponds to a specific capacity of 2857.7 mA h/g. Both specific capacity and binding energy are significantly larger than the corresponding value of graphite, this makes PG a promising candidate for the anode material in battery applications. The interactions between the Li atoms and PG can be easily tuned by an applied strain. Under biaxial strain of 16%, the binding energy of Li to PG is increased by 17% compared to its unstrained state.

  5. Development of High Capacity Split Stirling Cryocooler for HTS

    Science.gov (United States)

    Yumoto, Kenta; Nakano, Kyosuke; Hiratsuka, Yoshikatsu

    Sumitomo Heavy Industries, Ltd. (SHI) developed a high-power Stirling-type pulse tube cryocooler for cooling high-temperature superconductor (HTS) devices, such as superconductor motors, superconducting magnetic energy storage (SMES), and fault current limiters. The experimental results of a prototype pulse tube cryocooler were reported in September 2013. For a U-type expander, the cooling capacity was 151 W at 70 K with a compressor input power of 4 kW. Correspondingly, the coefficient of performance (COP) was about 0.038. However, the efficiency of the cryocooler is required to be COP > 0.1 and it was found that, theoretically, it is difficult to further improve the efficiency of a pulse tube cryocooler because the workflow generated at the hot end of the pulse tube cannot be recovered. Therefore, it was decided to change the expander to a free-piston type from a pulse tube type. A prototype was developed and preliminary experiments were conducted. A cooling capacity of 120 W at 70 K with a compressor input power of 2.15 kW with corresponding COP of 0.056, was obtained. The detailed results are reported in this paper.

  6. Remapping high-capacity, pre-attentive, fragile sensory memory.

    Science.gov (United States)

    Zerr, Paul; Gayet, Surya; Mulder, Kees; Pinto, Yaïr; Sligte, Ilja; Van der Stigchel, Stefan

    2017-11-21

    Humans typically make several saccades per second. This provides a challenge for the visual system as locations are largely coded in retinotopic (eye-centered) coordinates. Spatial remapping, the updating of retinotopic location coordinates of items in visuospatial memory, is typically assumed to be limited to robust, capacity-limited and attention-demanding working memory (WM). Are pre-attentive, maskable, sensory memory representations (e.g. fragile memory, FM) also remapped? We directly compared trans-saccadic WM (tWM) and trans-saccadic FM (tFM) in a retro-cue change-detection paradigm. Participants memorized oriented rectangles, made a saccade and reported whether they saw a change in a subsequent display. On some trials a retro-cue indicated the to-be-tested item prior to probe onset. This allowed sensory memory items to be included in the memory capacity estimate. The observed retro-cue benefit demonstrates a tFM capacity considerably above tWM. This provides evidence that some, if not all sensory memory was remapped to spatiotopic (world-centered, task-relevant) coordinates. In a second experiment, we show backward masks to be effective in retinotopic as well as spatiotopic coordinates, demonstrating that FM was indeed remapped to world-centered coordinates. Together this provides conclusive evidence that trans-saccadic spatial remapping is not limited to higher-level WM processes but also occurs for sensory memory representations.

  7. Remapping high-capacity, pre-Attentive, fragile sensory memory

    NARCIS (Netherlands)

    Zerr, Paul; Gayet, Surya; Mulder, Kees; Pinto, Yaïr; Sligte, Ilja; Van Der Stigchel, Stefan

    2017-01-01

    Humans typically make several saccades per second. This provides a challenge for the visual system as locations are largely coded in retinotopic (eye-centered) coordinates. Spatial remapping, the updating of retinotopic location coordinates of items in visuospatial memory, is typically assumed to be

  8. Remapping high-capacity, pre-attentive, fragile sensory memory

    NARCIS (Netherlands)

    Zerr, P.; Gayet, S.; Mulder, K.T.; Pinto, Y.; Sligte, I.G.; Stigchel, S. van der

    2017-01-01

    Humans typically make several saccades per second. This provides a challenge for the visual system as locations are largely coded in retinotopic (eye-centered) coordinates. Spatial remapping, the updating of retinotopic location coordinates of items in visuospatial memory, is typically assumed to be

  9. Jet Engines as High-Capacity Vacuum Pumps

    Science.gov (United States)

    Wojciechowski, C. J.

    1983-01-01

    Large diffuser operations envelope and long run times possible. Jet engine driven ejector/diffuser system combines two turbojet engines and variable-area-ratio ejector in two stages. Applications in such industrial proesses as handling corrosive fumes, evaporation of milk and fruit juices, petroleum distillation, and dehydration of blood plasma and penicillin.

  10. Fibre and components induced limitations in high capacity optical networks

    DEFF Research Database (Denmark)

    Peucheret, Christophe

    2003-01-01

    The design of future all-optical networks relies on the knowledge of the physical layer transport properties. In this thesis, we focus on two types of system impairments: those induced by the non-ideal transfer functions of optical filters to be found in network elements such as optical add...... design in order to maximise the spectral efficiency in a four add-drop node ring network. The concept of "normalised transmission sections" is introduced in order to ease the dimensioning of transparent domains in future all-optical networks. Normalised sections based on standard single mode fibre (SMF......-drop multiplexers (OADM) and optical cross-connects (OXC), as well as those due to the interaction of group-velocity dispersion, optical fibre non-linearities and accumulation of amplifier noise in the transmission path. The dispersion of fibre optics components is shown to limit their cascadability. Dispersion...

  11. Multicore fibers for high-capacity submarine transmission systems

    DEFF Research Database (Denmark)

    Nooruzzaman, Md.; Morioka, Toshio

    2018-01-01

    Applications of multicore fibers (MCFs) in undersea transmission systems are investigated, and various potential architectures of branching units for MCF-based undersea transmission systems are presented. Some MCF-based submarine network architectures based on the amount of data traffic are also...

  12. Photodimerization in dipeptides for high capacity optical digital storage

    DEFF Research Database (Denmark)

    Ramanujam, P.S.; Berg, R.H.

    2004-01-01

    We have developed peptide materials with chromophores that undergo cycloaddition, suitable for terabit optical digital storage in a 5.25 in. disc. The rationale behind this design is that the length and rigidity of the backbone can be adjusted to facilitate the formation of a photodimer without...... large physical movements of the chromophores on exposure to UV light. Initially strongly absorbing films transmit up to 50% of light on irradiation at dimerizing wavelengths. This property can be utilized to record grey levels. An intensity-dependent transmission behavior has been observed that may...

  13. Highly efficient distributed generation and high-capacity energy storage

    DEFF Research Database (Denmark)

    Hemmes, Kas; Guerrero, Josep M.; Zhelev, Toshko

    2012-01-01

    With the growing amount of decentralized power production the design and operation of the grid has to be reconsidered. New problems include the two-way flow of electricity and maintaining the power balance given the increased amount of uncertain and fluctuating renewable energy sources like wind...... and solar that deliver electricity to the grid. Solution directions are the development of smart grids, demand side management, virtual power plants and storage of electricity. These are directions that, rightly so, are already attracting a lot of attention and R&D funding. In this paper critical issues...... and fuel that can also fulfill a storage function....

  14. Why high-capacity manipulators and lead glass windows

    International Nuclear Information System (INIS)

    Grisham, D.L.; Lambert, J.E.

    1981-01-01

    The Monitor remote-handling system was developed to maintain the main experimental beam line at the Clinton P. Anderson Meson Physics Facility (LAMPF) of the Los Alamos National Laboratory. The technology and operating experience developed at LAMPF can be applied to other areas where handling of radioactive, hazardous, or toxic materials is required. These could include radiological incidents similar to Three Mile Island and toxic material spills, such as chlorine tank car derailments, where no provision for remote-handling exists. The technology can also be applied to routine radioactive remote-handling operations now conducted in conventional hot cells. These operations are normally done using mechanical master-slave manipulators with viewing through lead glass windows. The conventional facility can be replaced by a plain shielded box with an equivalent of the front end of Monitor inside. Master-slave manipulators of the future should be of 10-kg capacity with a force-reflection threshold of 0.2, minimum size, and provision for total sealing

  15. Burnup credit applications in a high-capacity truck cask

    International Nuclear Information System (INIS)

    Boshoven, J.K.

    1993-01-01

    The use of burnup credit in the criticality safety analysis of the GA-4 Cask increases the cask's capacity from three spent fuel assemblies to four, resulting in reduced public and occupational risk and reduced life cycle costs. GA's criticality calculations for burnup credit, including the associated uncertainties and analytical bias, establish the minimum burnup required as a function of initial enrichment to maintain K eff ≤ 0.95 under any conceivable condition. The minimum burnup requirement as a function of initial enrichment has been determined to be 15,000 MWd/MTU for 3.5 wt% U-235 fuel, 20,000 MWd/MTU for 4.0 wt% U-235 fuel and 25,000 MWd/MTU for 4.5 wt% U-235 fuel. The minimum burnup requirement as a function of enrichment is well below the typical burnup levels seen in the current and projected spent fuel inventory. (J.P.N.)

  16. High Capacity Optical Channels for Bioinformation Transfer: Acupuncture Meridians

    Czech Academy of Sciences Publication Activity Database

    Pokorný, Jiří; Martan, Tomáš; Foletti, A.

    2012-01-01

    Roč. 5, č. 1 (2012), s. 34-41 ISSN 2005-2901 R&D Projects: GA ČR(CZ) GAP102/11/0649 Institutional support: RVO:67985882 Keywords : Electromagnetic fields * Cellular biophysics * Cancer Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering

  17. High-capacity composite adsorbents for nucleic acids.

    Science.gov (United States)

    Tiainen, Peter; Rokebul Anower, M; Larsson, Per-Olof

    2011-08-05

    Cytopore™ is a bead-shaped, macroporous and easily compressible cellulose-based anion-exchange material intended for cultivation of anchor-dependent animal cells. Reticulated vitreous carbon (RVC) is a strong, non-compressible, high voidage (97%) matrix material that can be cut to desired geometrical shapes. Cytopore and RVC were combined to cylindrical composites (25 mm × 10 mm) fitted inside chromatography columns. The composite combined the advantageous properties of both its constituents, making it suitable for column chromatography. The composite could withstand very high flow rates without compaction of the bed (>25 column volumes/min; 4000 cm h(-1)). Chromatography runs with tracers showed a low HETP value (0.3mm), suggesting that pore flow was in operation. The dynamic binding capacities (10% breakthrough) per gram of dry weight Cytopore were determined for several compounds including DNA and RNA and were found to be 240-370 mg/g. The composite was used to isolate pUC 18-type plasmids from a cleared alkaline lysate in a good yield. Confocal microscopy studies showed that plasmids were bound not only to the surface of the Cytopore material but also within the matrix walls, thus offering an explanation to the very high binding capacities observed. The concept of using a composite prepared from a mechanically weak, high-binding material and a strong scaffold material may be applied to other systems as well. Copyright © 2011 Elsevier B.V. All rights reserved.

  18. Selection of local extremophile lactic acid bacteria with high capacity ...

    African Journals Online (AJOL)

    This study is related to the isolation and identification of strains of local thermophilic lactic acid bacteria belonging to the species, Streptococcus thermophilus and Lactobacillus bulgaricus. These bacteria can exist under extreme conditions of the digestive tract (acidity and high concentration of bile salts) and have a high ...

  19. High capacity adsorption media and method of producing

    Science.gov (United States)

    Tranter, Troy J.; Mann, Nicholas R.; Todd, Terry A.; Herbst, Ronald S.

    2010-10-05

    A method of producing an adsorption medium to remove at least one constituent from a feed stream. The method comprises dissolving and/or suspending at least one metal compound in a solvent to form a metal solution, dissolving polyacrylonitrile into the metal solution to form a PAN-metal solution, and depositing the PAN-metal solution into a quenching bath to produce the adsorption medium. The at least one constituent, such as arsenic, selenium, or antimony, is removed from the feed stream by passing the feed stream through the adsorption medium. An adsorption medium having an increased metal loading and increased capacity for arresting the at least one constituent to be removed is also disclosed. The adsorption medium includes a polyacrylonitrile matrix and at least one metal hydroxide incorporated into the polyacrylonitrile matrix.

  20. High capacity, high speed histogramming data acquisition memory

    International Nuclear Information System (INIS)

    Epstein, A.; Boulin, C.

    1996-01-01

    A double width CAMAC DRAM store module was developed for use as a histogramming memory in fast time-resolved synchrotron radiation applications to molecular biology. High speed direct memory modify (3 MHz) is accomplished by using a discrete DRAM controller and fast page mode access. The module can be configured using standard SIMMs to sizes of up to 64M-words. The word width is 16 bit and the module can handle overflows by storing the overflow addresses in a dedicated FIFO. Simultaneous front panel DMM/DMI access and CAMAC readout of the overflow addresses is supported

  1. High-capacity electrode materials for electrochemical energy storage

    Indian Academy of Sciences (India)

    2015-06-02

    Jun 2, 2015 ... We discuss the role of nanoscale effects on the electrochemical ..... tems and BASF for developing high energy density lithium ion cells for plug-in electric ..... SEM and STEM images showing typical shapes and sizes of FeF2 ...

  2. Ultra-High Capacity Networking Enabled By Optical Technologies

    Science.gov (United States)

    2003-08-01

    17 vi 150 3.1.1 The Microkernel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 19 3.1.2 Vertically...Architectures . . . . . . . . . . . . . . . . . . 84 7.2.1 Microkernels . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 7.2.2 Vertically...18 3.2 Microkernel -based operating system structure . . . . . . . . . . . . . . . . . 20 3.3 Vertically

  3. Photonics applications in high-capacity data link terminals

    Science.gov (United States)

    Shi, Zan; Foshee, James J.

    2001-12-01

    Radio systems and, in particular, RF data link systems are evolving toward progressively more bandwidth and higher data rates. For many military RF data link applications the data transfer requirements exceed one Gigabit per second. Airborne collectors need to transfer sensor information and other large data files to ground locations and other airborne terminals, including the rel time transfer of files. It is a challenge to the system designer to provide a system design, which meets the RF link budget requirements for a one Gigabit per second data link; and there is a corresponding challenge in the development of the terminal architecture and hardware. The utilization of photonic circuitry and devices as a part of the terminal design offers the designer some alternatives to the conventional RF hardware design within the radio. Areas of consideration for the implementation of photonic technology include Gigabit per second baseband data interfaces with fiber along with the associated clocking rates and extending these Gigabit data rates into the radio for optical processing technology; optical interconnections within the individual circuit boards in the radio; and optical backplanes to allow the transfer of not only the Gigabit per second data rates and high speed clocks but other RF signals within the radio. True time delay using photonics in phased array antennas has been demonstrated and is an alternative to the conventional phase shifter designs used in phased array antennas, and remoting of phased array antennas from the terminal electronics in the Ku and Ka frequency bands using fiber optics as the carrier to minimize the RF losses, negate the use of the conventional waveguides, and allow the terminal equipment to be located with other electronic equipment in the aircraft suitable for controlled environment, ready access, and maintenance. The various photonics design alternatives will be discussed including specific photonic design approaches. Packaging, performance, and affordability of the various design alternatives will also be discussed.

  4. Early Elevation of Serum MMP-3 and MMP-12 Predicts Protection from World Trade Center-Lung Injury in New York City Firefighters: A Nested Case-Control Study

    Science.gov (United States)

    Echevarria, Ghislaine C.; Comfort, Ashley L.; Naveed, Bushra; Prezant, David J.; Rom, William N.; Nolan, Anna

    2013-01-01

    Objective After 9/11/2001, some Fire Department of New York (FDNY) workers had excessive lung function decline. We hypothesized that early serum matrix metalloproteinases (MMP) expression predicts World Trade Center-Lung Injury (WTC-LI) years later. Methods This is a nested case-control analysis of never-smoking male firefighters with normal pre-exposure Forced Expiratory Volume in one second (FEV1) who had serum drawn up to 155 days post 9/11/2001. Serum MMP-1, 2,3,7,8, 9, 12 and 13 were measured. Cases of WTC-LI (N = 70) were defined as having an FEV1 one standard deviation below the mean (FEV1≤77%) at subspecialty pulmonary evaluation (SPE) which was performed 32 months (IQR 21–53) post-9/11. Controls (N = 123) were randomly selected. We modeled MMP's ability as a predictor of cases status with logistic regression adjusted for time to blood draw, exposure intensity, weight gain and pre-9/11 FEV1. Results Each log-increase in MMP-3 and MMP-12 showed reduced odds of developing WTC-LI by 73% and 54% respectively. MMP-3 and MMP-12 consistently clustered together in cases, controls, and the cohort. Increasing time to blood draw significantly and independently increased the risk of WTC-LI. Conclusions Elevated serum levels of MMP-3 and MMP-12 reduce the risk of developing WTC-LI. At any level of MMP-3 or 12, increased time to blood draw is associated with a diminished protective effect. PMID:24146820

  5. Early elevation of serum MMP-3 and MMP-12 predicts protection from World Trade Center-lung injury in New York City Firefighters: a nested case-control study.

    Directory of Open Access Journals (Sweden)

    Sophia Kwon

    Full Text Available OBJECTIVE: After 9/11/2001, some Fire Department of New York (FDNY workers had excessive lung function decline. We hypothesized that early serum matrix metalloproteinases (MMP expression predicts World Trade Center-Lung Injury (WTC-LI years later. METHODS: This is a nested case-control analysis of never-smoking male firefighters with normal pre-exposure Forced Expiratory Volume in one second (FEV1 who had serum drawn up to 155 days post 9/11/2001. Serum MMP-1, 2,3,7,8, 9, 12 and 13 were measured. Cases of WTC-LI (N = 70 were defined as having an FEV1 one standard deviation below the mean (FEV1 ≤ 77% at subspecialty pulmonary evaluation (SPE which was performed 32 months (IQR 21-53 post-9/11. Controls (N = 123 were randomly selected. We modeled MMP's ability as a predictor of cases status with logistic regression adjusted for time to blood draw, exposure intensity, weight gain and pre-9/11 FEV1. RESULTS: Each log-increase in MMP-3 and MMP-12 showed reduced odds of developing WTC-LI by 73% and 54% respectively. MMP-3 and MMP-12 consistently clustered together in cases, controls, and the cohort. Increasing time to blood draw significantly and independently increased the risk of WTC-LI. CONCLUSIONS: Elevated serum levels of MMP-3 and MMP-12 reduce the risk of developing WTC-LI. At any level of MMP-3 or 12, increased time to blood draw is associated with a diminished protective effect.

  6. An exploration of warfighting and firefighting doctrine

    Science.gov (United States)

    Michael T. DeGrosky; Alen Slijepcevic

    2015-01-01

    Over the past two decades, wildland fire professionals have been confronted with worsening conditions and complex challenges that cry out for change and new ways of thinking. However, change requires a framework within which people reliably translate policy into timely, effective action. Doctrine, or a body of teachings, instructions, taught principles, or positions,...

  7. Fire-fighting burning oil wells

    International Nuclear Information System (INIS)

    Newbury, Herbert; Risk, Stewart.

    1993-01-01

    A method of extinguishing burning oil wells is presented which involves dispensing liquid nitrogen to the burning site to prevent or inhibit oxygen from fuelling the flames. To carry out the method a remotely operated vehicle is described which is provided with a source of liquid nitrogen and an articulated deployment boom capable of supplying the liquid nitrogen to the site of a burning oil well. (Author)

  8. Risk complexity and the wildland firefighter

    Science.gov (United States)

    Ivan Pupulidy

    2012-01-01

    Between 2000 and 2010 the US Forest Service and the Department of the Interior experienced 82 wildland fire fatalities. Our most recent organizational focus has been to eliminate fatalities. The chief of the USFS, in a letter to all employees, asked us to "suspend disbelief" with regard to the concept of a "zero fatality organization". This plea...

  9. The PHLAME firefighters' study: feasibility and findings.

    Science.gov (United States)

    Elliot, Diane L; Goldberg, Linn; Duncan, Terry E; Kuehl, Kerry S; Moe, Esther L; Breger, Rosemary K R; DeFrancesco, Carol L; Ernst, Denise B; Stevens, Victor J

    2004-01-01

    To assess efficacy of 2 worksite health promotion interventions. Randomly assign 3 fire stations to (a) team-based curriculum, (b) individual counselor meetings, and (c) control. Both interventions were feasible and acceptable, and they resulted in significant reductions in LDL cholesterol. The team approach significantly increased coworker cohesion, personal exercise habits, and coworkers' healthy behaviors. The one-on-one strategy significantly increased dietary self-monitoring, decreased fat intake, and reduced depressed feelings. Although both interventions promoted healthy behaviors, specific outcomes differed and reflected their conceptual underpinnings. The team-based curriculum is innovative and may enlist influences not accessed with individual formats.

  10. Fractionation of whey proteins with high-capacity superparamagnetic ion-exchangers

    DEFF Research Database (Denmark)

    Heebøll-Nielsen, Anders; Justesen, S.F.L.; Thomas, Owen R. T.

    2004-01-01

    to particles activated in sequential reactions with allyl bromide and N-bromosuccinimide yielded a maximum bovine serum albumin binding capacity of 156 mg g(-1) combined with a dissociation constant of 0.60 muM, whereas ion-exchangers created by linking polyethylene imine through superficial aldehydes bound up...... was then contacted with the anion-exchanger. For both adsorbent classes of ion-exchanger, desorption selectivity was subsequently studied by sequentially increasing the concentration of NaCl in the elution buffer. In the initial cation-exchange step quantitative removal of lactoferrin (LF) and lactoperoxidase (LPO......) was achieved with some simultaneous binding of immunoglobulins (1g). The immunoglobulins were separated from the other two proteins by desorbing with a low concentration of NaCl (less than or equal to0.4 M), whereas lactoferrin and lactoperoxidase were co-eluted in significantly purer form, e...

  11. Orbital Angular Momentum-based Space Division Multiplexing for High-capacity Underwater Optical Communications

    Science.gov (United States)

    Ren, Yongxiong; Li, Long; Wang, Zhe; Kamali, Seyedeh Mahsa; Arbabi, Ehsan; Arbabi, Amir; Zhao, Zhe; Xie, Guodong; Cao, Yinwen; Ahmed, Nisar; Yan, Yan; Liu, Cong; Willner, Asher J.; Ashrafi, Solyman; Tur, Moshe; Faraon, Andrei; Willner, Alan E.

    2016-09-01

    To increase system capacity of underwater optical communications, we employ the spatial domain to simultaneously transmit multiple orthogonal spatial beams, each carrying an independent data channel. In this paper, we show up to a 40-Gbit/s link by multiplexing and transmitting four green orbital angular momentum (OAM) beams through a single aperture. Moreover, we investigate the degrading effects of scattering/turbidity, water current, and thermal gradient-induced turbulence, and we find that thermal gradients cause the most distortions and turbidity causes the most loss. We show systems results using two different data generation techniques, one at 1064 nm for 10-Gbit/s/beam and one at 520 nm for 1-Gbit/s/beam; we use both techniques since present data-modulation technologies are faster for infrared (IR) than for green. For the 40-Gbit/s link, data is modulated in the IR, and OAM imprinting is performed in the green using a specially-designed metasurface phase mask. For the 4-Gbit/s link, a green laser diode is directly modulated. Finally, we show that inter-channel crosstalk induced by thermal gradients can be mitigated using multi-channel equalisation processing.

  12. Concepts for a low emittance-high capacity storage ring for the Diamond Light Source

    CERN Document Server

    Bartolini, Riccardo; Evans, Gwyndaf; Sawhney, Kawal; Zegenhagen, Joerg

    2017-01-01

    The Diamond Light Source is investigating several paths for a possible machine upgrade to Diamond II. The exercise is driven by a joint assessment of the science capabilities opened by a very low emittance ring and the machine design that will underpin them. The consultation is made on a beamline-by-beamline basis and has highlighted a significant preference for lattices that combine both a low emittance and large capacity for IDs.

  13. Crystalline-Amorphous Core−Shell Silicon Nanowires for High Capacity and High Current Battery Electrodes

    KAUST Repository

    Cui, Li-Feng

    2009-01-14

    Silicon is an attractive alloy-type anode material for lithium ion batteries because of its highest known capacity (4200 mAh/g). However silicon\\'s large volume change upon lithium insertion and extraction, which causes pulverization and capacity fading, has limited its applications. Designing nanoscale hierarchical structures is a novel approach to address the issues associated with the large volume changes. In this letter, we introduce a core-shell design of silicon nanowires for highpower and long-life lithium battery electrodes. Silicon crystalline- amorphous core-shell nanowires were grown directly on stainless steel current collectors by a simple one-step synthesis. Amorphous Si shells instead of crystalline Si cores can be selected to be electrochemically active due to the difference of their lithiation potentials. Therefore, crystalline Si cores function as a stable mechanical support and an efficient electrical conducting pathway while amorphous shells store Li ions. We demonstrate here that these core-shell nanowires have high charge storage capacity (̃1000 mAh/g, 3 times of carbon) with ̃90% capacity retention over 100 cycles. They also show excellent electrochemical performance at high rate charging and discharging (6.8 A/g, ̃20 times of carbon at 1 h rate). © 2009 American Chemical Society.

  14. Synthesis of high capacity cation exchangers from a low-grade Chinese natural zeolite

    International Nuclear Information System (INIS)

    Wang Yifei; Lin Feng

    2009-01-01

    The Chinese natural zeolite, in which clinoptilolite coexists with quartz was treated hydrothermally with NaOH solutions, either with or without fusion with NaOH powder as pretreatment. Zeolite Na-P, Na-Y and analcime were identified as the reacted products, depending on the reaction conditions such as NaOH concentration, reaction time and hydrothermal temperature. The products were identified by X-ray diffraction, and characterized by Fourier transform IR and ICP. With hydrothermal treatment after fusion of natural zeolite with NaOH, high purity of zeolite Na-Y and Na-P can be selectively formed, their cation exchange capacity (CEC) are 275 and 355 meq/100 g respectively, which are greatly higher than that of the natural zeolite (97 meq/100 g). Furthermore, the ammonium removal by the synthetic zeolite Na-P in aqueous solution was also studied. The equilibrium isotherms have been got and the influence of other cations present in water upon the ammonia uptake suggested an order of preference Ca 2+ > K + > Mg 2+ .

  15. Microwave photonics technologies supporting high capacity and flexible wireless communications systems

    DEFF Research Database (Denmark)

    Lu, Xiaofeng; Tatarczak, Anna; Rommel, Simon

    2015-01-01

    Emerging 5G wireless systems require technologies for increased capacity, guarantee robustness, low latency and flexibility. We review a number of approaches to provide the above based on microwave photonics and hybrid optical fiber-wireless communication techniques....

  16. β-Cobalt sulfide nanoparticles decorated graphene composite electrodes for high capacity and power supercapacitors

    Science.gov (United States)

    Qu, Baihua; Chen, Yuejiao; Zhang, Ming; Hu, Lingling; Lei, Danni; Lu, Bingan; Li, Qiuhong; Wang, Yanguo; Chen, Libao; Wang, Taihong

    2012-11-01

    Electrochemical supercapacitors have drawn much attention because of their high power and reasonably high energy densities. However, their performances still do not reach the demand of energy storage. In this paper β-cobalt sulfide nanoparticles were homogeneously distributed on a highly conductive graphene (CS-G) nanocomposite, which was confirmed by transmission electron microscopy analysis, and exhibit excellent electrochemical performances including extremely high values of specific capacitance (~1535 F g-1) at a current density of 2 A g-1, high-power density (11.98 kW kg-1) at a discharge current density of 40 A g-1 and excellent cyclic stability. The excellent electrochemical performances could be attributed to the graphene nanosheets (GNSs) which could maintain the mechanical integrity. Also the CS-G nanocomposite electrodes have high electrical conductivity. These results indicate that high electronic conductivity of graphene nanocomposite materials is crucial to achieving high power and energy density for supercapacitors.

  17. A high-capacity carbon prepared from renewable chicken feather biopolymer for supercapacitors

    Science.gov (United States)

    Wang, Qiang; Cao, Qi; Wang, Xianyou; Jing, Bo; Kuang, Hao; Zhou, Ling

    2013-03-01

    Micropopous chicken feather carbon (CFC) severing as electrode materials for the first time is prepared via the activation with KOH agent to different extents. The structure and electrochemical properties of CFC materials are characterized with N2 adsorption/desorption measurements, X-ray diffraction (XRD), transmission electron microscope (TEM), cyclic voltammetry (CV), galvanostatic charge/discharge cycling and electrochemical impedance spectroscopy (EIS). The obtained results show that CFC activated by KOH with KOH/CFC weight ratio of 4/1 (CFCA4) possesses the specific surface area of 1839 m2 g-1, average micropore diameter of 1.863 nm, and exhibits the highest initial specific capacitance of 302 F g-1 at current density of 1 A g-1 in 1 M H2SO4, and that even after 5000 cycles, CFCA4 specific capacitance is still as high as 253 F g-1. Furthermore, CFCA4 also delivers specific capacitance of 181 F g-1 at current density of 5 A g-1 and 168 F g-1 at current density of 10 A g-1. Accordingly, the microporous activated carbon material derived from chicken feather provides favorable prospect in electrode materials application in supercapacitors.

  18. Energy Saving High-Capacity Moderate Pressure Carbon Dioxide Storage System, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Our approach to high-pressure carbon dioxide storage will directly address the challenges associated with storage of compressed carbon dioxide - the need to reduce...

  19. Surface and bulk modified high capacity layered oxide cathodes with low irreversible capacity loss

    Science.gov (United States)

    Manthiram, Arumugam (Inventor); Wu, Yan (Inventor)

    2010-01-01

    The present invention includes compositions, surface and bulk modifications, and methods of making of (1-x)Li[Li.sub.1/3Mn.sub.2/3]O.sub.2.xLi[Mn.sub.0.5-yNi.sub.0.5-yCo.sub.2- y]O.sub.2 cathode materials having an O3 crystal structure with a x value between 0 and 1 and y value between 0 and 0.5, reducing the irreversible capacity loss in the first cycle by surface modification with oxides and bulk modification with cationic and anionic substitutions, and increasing the reversible capacity to close to the theoretical value of insertion/extraction of one lithium per transition metal ion (250-300 mAh/g).

  20. Crystalline-Amorphous Core−Shell Silicon Nanowires for High Capacity and High Current Battery Electrodes

    KAUST Repository

    Cui, Li-Feng; Ruffo, Riccardo; Chan, Candace K.; Peng, Hailin; Cui, Yi

    2009-01-01

    fading, has limited its applications. Designing nanoscale hierarchical structures is a novel approach to address the issues associated with the large volume changes. In this letter, we introduce a core-shell design of silicon nanowires for highpower

  1. Hydroxylamine hydrochloride: A novel anode material for high capacity lithium-ion batteries

    Science.gov (United States)

    Shao, Lianyi; Shu, Jie; Lao, Mengmeng; Lin, Xiaoting; Wu, Kaiqiang; Shui, Miao; Li, Peng; Long, Nengbing; Ren, Yuanlong

    2014-12-01

    H3NOHCl is used for the first time as anode material for lithium-ion batteries. Electrochemical results show that H3NOHCl with particle size of 4-12 μm can deliver an initial charge capacity of 1018.6 mAh g-1, which is much higher than commercial graphite. After 30 cycles, the reversible capacity can be kept at 676.1 mAh g-1 at 50 mA g-1. Up to 50 cycles, H3NOHCl still maintains a lithium storage capacity of 368.9 mAh g-1. Even cycled at 200 mA g-1, H3NOHCl can deliver a charge capacity of 715.7 mAh g-1. It suggests that H3NOHCl has high lithium storage capacity, excellent cycling stability and outstanding rate performance. Besides, the electrochemical reaction between H3NOHCl and Li is also investigated by various ex-situ techniques. It can be found that H3NOHCl irreversibly decomposes into Li3N and LiCl during the initial discharge process and LiNO2 can be formed after a reverse charge process.

  2. Fiber-wireless links supporting high-capacity W-band channels

    DEFF Research Database (Denmark)

    Vegas Olmos, Juan José; Tafur Monroy, Idelfonso

    2013-01-01

    Seamless convergence of fiber-optic and the wireless networks is of great interest for enabling transparent delivery of broadband services to users in different locations, including both metropolitan and rural areas. Current demand of bandwidth by end-users, especially using mobile devices...... latest findings and experimental results on the W-band, specifically on its 81-86GHz sub-band. These include photonic generation of millimeter-wave carriers and transmission performance of broadband signals on different types of fibers and span lengths....

  3. High capacity hybrid optical fiber-wireless links in 75–300GHz band

    DEFF Research Database (Denmark)

    Cavalcante, Lucas Costa Pereira; Vegas Olmos, Juan José; Tafur Monroy, Idelfonso

    2014-01-01

    Seamless convergence of fiber-optic and the wireless networks is of great interest for enabling transparent delivery of broadband services to users in different locations, including both metropolitan and rural areas. Current demand of bandwidth by end-users, especially using mobile devices......, is seeding the need to use bands located at the millimeter-wave region (30–300 GHz), mainly because of its inherent broadband nature. In our lab, we have conducted extensive research on high-speed photonic-wireless links in the W-band (75–110GHz). In this paper, we will present our latest findings...

  4. Optical signal processing for enabling high-speed, highly spectrally efficient and high capacity optical systems

    Science.gov (United States)

    Fazal, Muhammad Irfan

    The unabated demand for more capacity due to the ever-increasing internet traffic dictates that the boundaries of the state of the art maybe pushed to send more data through the network. Traditionally, this need has been satisfied by multiple wavelengths (wavelength division multiplexing), higher order modulation formats and coherent communication (either individually or combined together). WDM has the ability to reduce cost by using multiple channels within the same physical fiber, and with EDFA amplifiers, the need for O-E-O regenerators is eliminated. Moreover the availability of multiple colors allows for wavelength-based routing and network planning. Higher order modulation formats increases the capacity of the link by their ability to encode data in both the phase and amplitude of light, thereby increasing the bits/sec/Hz as compared to simple on-off keyed format. Coherent communications has also emerged as a primary means of transmitting and receiving optical data due to its support of formats that utilize both phase and amplitude to further increase the spectral efficiency of the optical channel, including quadrature amplitude modulation (QAM) and quadrature phase shift keying (QPSK). Polarization multiplexing of channels can double capacity by allowing two channels to share the same wavelength by propagating on orthogonal polarization axis and is easily supported in coherent systems where the polarization tracking can be performed in the digital domain. Furthermore, the forthcoming IEEE 100 Gbit/s Ethernet Standard, 802.3ba, provides greater bandwidth, higher data rates, and supports a mixture of modulation formats. In particular, Pol-MUX QPSK is increasingly becoming the industry's format of choice as the high spectral efficiency allows for 100 Gbit/s transmission while still occupying the current 50 GHz/channel allocation of current 10 Gbit/s OOK fiber systems. In this manner, 100 Gbit/s transfer speeds using current fiber links, amplifiers, and filters may be possible. Recently, interest has increased in exploring the spatial dimension of light to increase capacity, both in fiber as well as free-space communication channels. The orbital angular momentum (OAM) of light, carried by Laguerre-Gaussian (LG) beams have the interesting property that, in theory, an infinite number of OAMs can be transmitted; which due to its inherent orthogonality will not affect each other. Thus, in theory, one can increase the channel capacity arbitrarily. However, in practice, the device dimensions will reduce the number of OAMs used. In addition to advanced modulation formats, it is expected that optical signal processing may play a role in the future development of more efficient optical transmission systems. The hope is that performing signal processing in the optical domain may reduce optical-to-electronic conversion inefficiencies, eliminate bottlenecks and take advantage of the ultrahigh bandwidth inherent in optics. While 40 to 50 Gbit/s electronic components are the peak of commercial technology and 100 Gbit/s capable RF components are still in their infancy, optical signal processing of these high-speed data signals may provide a potential solution. Furthermore, any optical processing system or sub-system must be capable of handling the wide array of data formats and data rates that networks may employ. The work presented in this Ph.D. dissertation attempts at addressing the issue of optical processing for advanced optical modulation formats, and particularly explores the state of the art in increasing the capacity of an optical link by a combination of wavelength/phase/polarization/OAM dimensions of light. Spatial multiplexing and demultiplexing of both coherently and directly detected signals at the 100 Gbit/s Ethernet standard is addressed. The application of a continuously tunable all-optical delay for all-optical functionality like time-slot interchange at high data-rates is presented. Moreover the interplay of chirp generated by differently cross-phase modulation wavelength-convertors based on SOA-MZI with the residual dispersion of a fiber link is studied and the optimal operating conditions are explored

  5. Aluminum and silicon based phase change materials for high capacity thermal energy storage

    International Nuclear Information System (INIS)

    Wang, Zhengyun; Wang, Hui; Li, Xiaobo; Wang, Dezhi; Zhang, Qinyong; Chen, Gang; Ren, Zhifeng

    2015-01-01

    Six compositions of aluminum (Al) and silicon (Si) based materials: 87.8Al-12.2Si, 80Al–20Si, 70Al–30Si, 60Al–40Si, 45Al–40Si–15Fe, and 17Al–53Si–30Ni (atomic ratio), were investigated for potentially high thermal energy storage (TES) application from medium to high temperatures (550–1200 °C) through solid–liquid phase change. Thermal properties such as melting point, latent heat, specific heat, thermal diffusivity and thermal conductivity were investigated by differential scanning calorimetry and laser flash apparatus. The results reveal that the thermal storage capacity of the Al–Si materials increases with increasing Si concentration. The melting point and latent heat of 45Al–40Si–15Fe and 17Al–53Si–30Ni are ∼869 °C and ∼562 J g −1 , and ∼1079 °C and ∼960 J g −1 , respectively. The measured thermal conductivity of Al–Si binary materials depend on Si concentration and is higher than 80 W m −1  K −1 from room temperature to 500 °C, which is almost two orders of magnitude higher than those of salts that are commonly used phase change material for thermal energy storage. - Highlights: • Six kinds of materials were investigated for thermal energy storage (550–1200 °C). • Partial melting of Al–Si materials show progressively changing temperatures. • Studied materials can be used in three different working temperature ranges. • Materials are potentially good candidates for thermal energy storage applications.

  6. Autonomous Vehicles with High Capacity Computational Power Used in Remote Sensing Applications

    Data.gov (United States)

    National Aeronautics and Space Administration — The Unmanned Aerial System (UAS) industry in the United States is still very much in its infancy, but its potential impacts on the geospatial mapping and surveying...

  7. DNA MemoChip: Long-Term and High Capacity Information Storage and Select Retrieval.

    Science.gov (United States)

    Stefano, George B; Wang, Fuzhou; Kream, Richard M

    2018-02-26

    Over the course of history, human beings have never stopped seeking effective methods for information storage. From rocks to paper, and through the past several decades of using computer disks, USB sticks, and on to the thin silicon "chips" and "cloud" storage of today, it would seem that we have reached an era of efficiency for managing innumerable and ever-expanding data. Astonishingly, when tracing this technological path, one realizes that our ancient methods of informational storage far outlast paper (10,000 vs. 1,000 years, respectively), let alone the computer-based memory devices that only last, on average, 5 to 25 years. During this time of fast-paced information generation, it becomes increasingly difficult for current storage methods to retain such massive amounts of data, and to maintain appropriate speeds with which to retrieve it, especially when in demand by a large number of users. Others have proposed that DNA-based information storage provides a way forward for information retention as a result of its temporal stability. It is now evident that DNA represents a potentially economical and sustainable mechanism for storing information, as demonstrated by its decoding from a 700,000 year-old horse genome. The fact that the human genome is present in a cell, containing also the varied mitochondrial genome, indicates DNA's great potential for large data storage in a 'smaller' space.

  8. Nanostructured Block Polymer Membranes as High Capacity Adsorbers for the Capture of Metal Ions from Water

    Science.gov (United States)

    Boudouris, Bryan; Weidman, Jacob; Mulvenna, Ryan; Phillip, William

    The efficient removal of metal ions from aqueous streams is of significant import in applications ranging from industrial waste treatment to the purification of drinking water. An emerging paradigm associated with this separation is one that utilizes membrane adsorbers as a means by which to bind metal salt contaminants. Here, we demonstrate that the casting of an A-B-C triblock polymer using the self-assembly and non-solvent induced phase separation (SNIPS) methodology results in a nanoporous membrane geometry. The nature of the triblock polymer affords an extremely high density of binding sites within the membrane. As such, we demonstrate that the membranes with binding capacities equal to that of state-of-the-art packed bed columns. Moreover, because the affinity of the C moiety can be tuned, highly selective binding events can occur based solely on the chemistry of the block polymer and the metal ions in solution (i.e., in a manner that is independent of the size of the metal ions). Due to these combined facts, these membranes efficiently remove heavy metal (e.g., lead- and cadmium-based) salts from contaminated water streams with greater than 95% efficiency. Finally, we show that the membranes can be regenerated through a simple treatment in order to provide long-lasting adsorber systems as well. Thus, it is anticipated that these nanostructured triblock polymer membranes are a platform by which to obtain next-generation water purification processes.

  9. A High-Capacity Image Data Hiding Scheme Using Adaptive LSB Substitution

    Directory of Open Access Journals (Sweden)

    H. Yang

    2009-12-01

    Full Text Available Many existing steganographic methods hide more secret data into edged areas than smooth areas in the host image, which does not differentiate textures from edges and causes serious degradation in actual edge areas. To avoid abrupt changes in image edge areas, as well as to achieve better quality of the stego-image, a novel image data hiding technique by adaptive Least Significant Bits (LSBs substitution is proposed in this paper. The scheme exploits the brightness, edges, and texture masking of the host image to estimate the number k of LSBs for data hiding. Pixels in the noise non-sensitive regions are embedded by a k-bit LSB substitution with a lager value of k than that of the pixels in noise sensitive regions. Moreover, an optimal pixel adjustment process is used to enhance stego-image visual quality obtained by simple LSB substitution method. To ensure that the adaptive number k of LSBs remains unchanged after pixel modification, the LSBs number is computed by the high-order bits rather than all the bits of the image pixel value. The theoretical analyses and experiment results show that the proposed method achieves higher embedding capacity and better stegoimage quality compared with some existing LSB methods.

  10. Step by step replacement of aging electronic equipment: a way to maintain high capacity factors

    International Nuclear Information System (INIS)

    Wilder, O.

    1990-01-01

    The paper discusses the following topics: replacement concept, aging, replacement, strategy and the Swedish situation. The replacement of important central systems started already 1986 in Oskarshamn 1

  11. Final Report: Laboratory Development of a High Capacity Gas-Fired Paper Dryer

    Energy Technology Data Exchange (ETDEWEB)

    Yaroslav Chudnovsky; Aleksandr Kozlov; Lester Sherrow

    2005-09-30

    Paper drying is the most energy-intensive and temperature-critical aspect of papermaking. It is estimated that about 67% of the total energy required in papermaking is used to dry paper. The conventional drying method uses a series of steam-heated metal cylinders that are required to meet ASME codes for pressure vessels, which limits the steam pressure to about 160 psig. Consequently, the shell temperature and the drying capacity are also limited. Gas Technology Institute together with Boise Paper Solutions, Groupe Laperrier and Verreault (GL&V) USA Inc., Flynn Burner Corporation and with funding support from the U.S. Department of Energy, U.S. natural gas industry, and Gas Research Institute is developing a high efficiency gas-fired paper dryer based on a combination of a ribbon burner and advanced heat transfer enhancement technique. The Gas-Fired Paper Dryer (GFPD) is a high-efficiency alternative to conventional steam-heated drying drums that typically operate at surface temperatures in the 300 deg F range. The new approach was evaluated in laboratory and pilot-scale testing at the Western Michigan University Paper Pilot Plant. Drum surface temperatures of more than 400 deg F were reached with linerboard (basis weight 126 lb/3000 ft2) production and resulted in a 4-5 times increase in drying rate over a conventional steam-heated drying drum. Successful GFPD development and commercialization will provide large energy savings to the paper industry and increase paper production rates from dryer-limited (space- or steam-limited) paper machines by an estimated 10 to 20%, resulting in significant capital costs savings for both retrofits and new capacity.

  12. Laboratory Development of A High Capacity Gas-Fired paper Dryer

    Energy Technology Data Exchange (ETDEWEB)

    Chudnovsky, Yaroslav [Gas Technology Institute, Des Plaines, IL (United States); Kozlov, Aleksandr [Gas Technology Institute, Des Plaines, IL (United States); Sherrow, Lester [Gas Technology Institute, Des Plaines, IL (United States)

    2005-09-30

    Paper drying is the most energy-intensive and temperature-critical aspect of papermaking. It is estimated that about 67% of the total energy required in papermaking is used to dry paper. The conventional drying method uses a series of steam-heated metal cylinders that are required to meet ASME codes for pressure vessels, which limits the steam pressure to about 160 psig. Consequently, the shell temperature and the drying capacity are also limited. Gas Technology Institute together with Boise Paper Solutions, Groupe Laparrier and Verreault (GL&V) USA Inc., Flynn Burner Corporation and with funding support from the U.S. Department of Energy, U.S. natural gas industry, and Gas Research Institute is developing a high efficiency gas-fired paper dryer based on a combination of a ribbon burner and advanced heat transfer enhancement technique. The Gas-Fired Paper Dryer (GFPD) is a high-efficiency alternative to conventional steam-heated drying drums that typically operate at surface temperatures in the 300ºF range. The new approach was evaluated in laboratory and pilot-scale testing at the Western Michigan University Paper Pilot Plant. Drum surface temperatures of more than 400ºF were reached with linerboard (basis weight 126 lb/3000 ft2) production and resulted in a 4-5 times increase in drying rate over a conventional steam-heated drying drum. Successful GFPD development and commercialization will provide large energy savings to the paper industry and increase paper production rates from dryer-limited (space- or steam-limited) paper machines by an estimated 10 to 20%, resulting in significant capital costs savings for both retrofits and new capacity.

  13. High Capacity Cathode and Carbon Nanotube-Supported Anode for Enhanced Energy Density Batteries

    Science.gov (United States)

    2017-09-07

    110-118, 2014. [15] J. B. Fei, et al., “Controlled preparation of MnO2 hierarchical hollow nanostructures and their application in water treatment ...and fixed load step ( grey shading) cell voltage and electrode potentials plotted vs. cell capacity, (b) 5th cycle discharge and fixed load step ( grey ...42  Figure 26. (a) 5th cycle discharge and fixed load step ( grey

  14. High capacity hydrogen absorption in transition-metal ethylene complexes: consequences of nanoclustering

    International Nuclear Information System (INIS)

    Phillips, A B; Shivaram, B S

    2009-01-01

    We have recently shown that organo-metallic complexes formed by laser ablating transition metals in ethylene are high hydrogen absorbers at room temperature (Phillips and Shivaram 2008 Phys. Rev. Lett. 100 105505). Here we show that the absorption percentage depends strongly on the ethylene pressure. High ethylene pressures (>100 mTorr) result in a lowered hydrogen uptake. Transmission electron microscopy measurements reveal that while low pressure ablations result in metal atoms dispersed uniformly on a near atomic scale, high pressure ones yield distinct nanoparticles with electron energy-loss spectroscopy demonstrating that the metal atoms are confined solely to the nanoparticles.

  15. Development of a Process for a High Capacity Arc Heater Production of Silicon for Solar Arrays

    Science.gov (United States)

    Reed, W. H.

    1979-01-01

    A program was established to develop a high temperature silicon production process using existing electric arc heater technology. Silicon tetrachloride and a reductant (sodium) are injected into an arc heated mixture of hydrogen and argon. Under these high temperature conditions, a very rapid reaction is expected to occur and proceed essentially to completion, yielding silicon and gaseous sodium chloride. Techniques for high temperature separation and collection were developed. Included in this report are: test system preparation; testing; injection techniques; kinetics; reaction demonstration; conclusions; and the project status.

  16. Development of a process for high capacity arc heater production of silicon for solar arrays

    Science.gov (United States)

    Meyer, T. N.

    1980-01-01

    A high temperature silicon production process using existing electric arc heater technology is discussed. Silicon tetrachloride and a reductant, liquid sodium, were injected into an arc heated mixture of hydrogen and argon. Under these high temperature conditions, a very rapid reaction occurred, yielding silicon and gaseous sodium chloride. Techniques for high temperature separation and collection of the molten silicon were developed. The desired degree of separation was not achieved. The electrical, control and instrumentation, cooling water, gas, SiCl4, and sodium systems are discussed. The plasma reactor, silicon collection, effluent disposal, the gas burnoff stack, and decontamination and safety are also discussed. Procedure manuals, shakedown testing, data acquisition and analysis, product characterization, disassembly and decontamination, and component evaluation are reviewed.

  17. Lithium decoration of three dimensional boron-doped graphene frameworks for high-capacity hydrogen storage

    International Nuclear Information System (INIS)

    Wang, Yunhui; Meng, Zhaoshun; Liu, Yuzhen; You, Dongsen; Wu, Kai; Lv, Jinchao; Wang, Xuezheng; Deng, Kaiming; Lu, Ruifeng; Rao, Dewei

    2015-01-01

    Based on density functional theory and the first principles molecular dynamics simulations, a three-dimensional B-doped graphene-interconnected framework has been constructed that shows good thermal stability even after metal loading. The average binding energy of adsorbed Li atoms on the proposed material (2.64 eV) is considerably larger than the cohesive energy per atom of bulk Li metal (1.60 eV). This value is ideal for atomically dispersed Li doping in experiments. From grand canonical Monte Carlo simulations, high hydrogen storage capacities of 5.9 wt% and 52.6 g/L in the Li-decorated material are attained at 298 K and 100 bars

  18. High-Capacity Quantum Secure Direct Communication Based on Quantum Hyperdense Coding with Hyperentanglement

    International Nuclear Information System (INIS)

    Wang Tie-Jun; Li Tao; Du Fang-Fang; Deng Fu-Guo

    2011-01-01

    We present a quantum hyperdense coding protocol with hyperentanglement in polarization and spatial-mode degrees of freedom of photons first and then give the details for a quantum secure direct communication (QSDC) protocol based on this quantum hyperdense coding protocol. This QSDC protocol has the advantage of having a higher capacity than the quantum communication protocols with a qubit system. Compared with the QSDC protocol based on superdense coding with d-dimensional systems, this QSDC protocol is more feasible as the preparation of a high-dimension quantum system is more difficult than that of a two-level quantum system at present. (general)

  19. Synthesis, characterization and dye removal ability of high capacity polymeric adsorbent: Polyaminoimide homopolymer

    Energy Technology Data Exchange (ETDEWEB)

    Mahmoodi, Niyaz Mohammad, E-mail: nm_mahmoodi@aut.ac.ir [Department of Environmental Research, Institute for Color Science and Technology, Tehran (Iran, Islamic Republic of); Najafi, Farhood [Department of Resin and Additives, Institute for Color Science and Technology, Tehran (Iran, Islamic Republic of); Khorramfar, Shooka [Department of Environmental Research, Institute for Color Science and Technology, Tehran (Iran, Islamic Republic of); Textile Engineering Department, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of); Amini, Farrokhlegha [Department of Environmental Research, Institute for Color Science and Technology, Tehran (Iran, Islamic Republic of); Arami, Mokhtar [Textile Engineering Department, Amirkabir University of Technology, Tehran (Iran, Islamic Republic of)

    2011-12-30

    Highlights: Black-Right-Pointing-Pointer Polyaminoimide homopolymer (PAIHP) was synthesized and characterized. Black-Right-Pointing-Pointer Kinetics data followed pseudo-second order kinetic model. Black-Right-Pointing-Pointer Isotherm data followed Langmuir isotherm. Black-Right-Pointing-Pointer Q{sub 0} for DR31, DR23, DB22 and AB25 was 6667, 5555, 9090 and 5882 mg/g, respectively. Black-Right-Pointing-Pointer PAIHP was regenerated at pH 12. - Abstract: In this paper, polyaminoimide homopolymer (PAIHP) was synthesized and its dye removal ability was investigated. Physical characteristics of PAIHP were studied using Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). Direct Red 31 (DR31), Direct Red 23 (DR23), Direct Black 22 (DB22) and Acid Blue 25 (AB25) were used as model compounds. The kinetic and isotherm of dye adsorption were studied. The effect of operational parameter such as adsorbent dosage, pH and salt on dye removal was evaluated. Adsorption kinetic of dyes followed pseudo-second order kinetics. The maximum dye adsorption capacity (Q{sub 0}) of PAIHP was 6667 mg/g, 5555 mg/g, 9090 mg/g and 5882 mg/g for DR31, DR23, DB22 and AB25, respectively. It was found that adsorption of DR31, DR23, DB22 and AB25 onto PAIHP followed with Langmuir isotherm. Dye desorption tests (adsorbent regeneration) showed that the maximum dye release of 90% for DR31, 86% for DR23, 87% for DB22 and 90% for AB25 were achieved in aqueous solution at pH 12. The results showed that the PAIHP as a polymeric adsorbent with high dye adsorption capacity might be a suitable alternative to remove dyes from colored wastewater.

  20. Synthesis, characterization and dye removal ability of high capacity polymeric adsorbent: Polyaminoimide homopolymer

    International Nuclear Information System (INIS)

    Mahmoodi, Niyaz Mohammad; Najafi, Farhood; Khorramfar, Shooka; Amini, Farrokhlegha; Arami, Mokhtar

    2011-01-01

    Highlights: ► Polyaminoimide homopolymer (PAIHP) was synthesized and characterized. ► Kinetics data followed pseudo-second order kinetic model. ► Isotherm data followed Langmuir isotherm. ► Q 0 for DR31, DR23, DB22 and AB25 was 6667, 5555, 9090 and 5882 mg/g, respectively. ► PAIHP was regenerated at pH 12. - Abstract: In this paper, polyaminoimide homopolymer (PAIHP) was synthesized and its dye removal ability was investigated. Physical characteristics of PAIHP were studied using Fourier transform infrared (FTIR) and scanning electron microscopy (SEM). Direct Red 31 (DR31), Direct Red 23 (DR23), Direct Black 22 (DB22) and Acid Blue 25 (AB25) were used as model compounds. The kinetic and isotherm of dye adsorption were studied. The effect of operational parameter such as adsorbent dosage, pH and salt on dye removal was evaluated. Adsorption kinetic of dyes followed pseudo-second order kinetics. The maximum dye adsorption capacity (Q 0 ) of PAIHP was 6667 mg/g, 5555 mg/g, 9090 mg/g and 5882 mg/g for DR31, DR23, DB22 and AB25, respectively. It was found that adsorption of DR31, DR23, DB22 and AB25 onto PAIHP followed with Langmuir isotherm. Dye desorption tests (adsorbent regeneration) showed that the maximum dye release of 90% for DR31, 86% for DR23, 87% for DB22 and 90% for AB25 were achieved in aqueous solution at pH 12. The results showed that the PAIHP as a polymeric adsorbent with high dye adsorption capacity might be a suitable alternative to remove dyes from colored wastewater.

  1. Sc-Decorated Porous Graphene for High-Capacity Hydrogen Storage: First-Principles Calculations.

    Science.gov (United States)

    Chen, Yuhong; Wang, Jing; Yuan, Lihua; Zhang, Meiling; Zhang, Cairong

    2017-08-02

    The generalized gradient approximation (GGA) function based on density functional theory is adopted to investigate the optimized geometrical structure, electron structure and hydrogen storage performance of Sc modified porous graphene (PG). It is found that the carbon ring center is the most stable adsorbed position for a single Sc atom on PG, and the maximum number of adsorbed H₂ molecules is four with the average adsorption energy of -0.429 eV/H₂. By adding a second Sc atom on the other side of the system, the hydrogen storage capacity of the system can be improved effectively. Two Sc atoms located on opposite sides of the PG carbon ring center hole is the most suitable hydrogen storage structure, and the hydrogen storage capacity reach a maximum 9.09 wt % at the average adsorption energy of -0.296 eV/H₂. The adsorption of H₂ molecules in the PG system is mainly attributed to orbital hybridization among H, Sc, and C atoms, and Coulomb attraction between negatively charged H₂ molecules and positively charged Sc atoms.

  2. Fe3O4/carbon hybrid nanoparticle electrodes for high-capacity electrochemical capacitors.

    Science.gov (United States)

    Lee, Jun Seop; Shin, Dong Hoon; Jun, Jaemoon; Lee, Choonghyeon; Jang, Jyongsik

    2014-06-01

    Fe3O4/carbon hybrid nanoparticles (FeCHNPs) were fabricated using dual-nozzle electrospraying, vapor deposition polymerization (VDP), and carbonization. FeOOH nanoneedles decorated with polypyrrole (PPy) nanoparticles (FePNPs) were fabricated by electrospraying pristine PPy mixed with FeCl3 solution, followed by heating stirring reaction. A PPy coating was then formed on the FeOOH nanoneedles through a VDP process. FeCHNPs were produced through carbonization of PPy and FeOOH phase transitions. These hybrid carbon nanoparticles (NPs) were used to build electrodes of electrochemical capacitors. The specific capacitance of the FeCHNPs was 455 F g(-1), which is larger than that of pristine PPy NPs (105 F g(-1)) or other hybrid PPy NPs. Furthermore, the FeCHNP-based capacitors exhibited better cycle stability during charge-discharge cycling than other hybrid NP capacitors. This is because the carbon layer on the Fe3 O4 surface formed a protective coating, preventing damage to the electrode materials during the charge-discharge processes. This fabrication technique is an effective approach for forming stable carbon/metal oxide nanostructures for energy storage applications. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Multiband Carrierless Amplitude Phase Modulation for High Capacity Optical Data Links

    DEFF Research Database (Denmark)

    Iglesias Olmedo, Miguel; Zuo, Tianjian; Jensen, Jesper Bevensee

    2014-01-01

    . The reported experiment uses MultiCAP to achieve 102.4 Gb/s transmission, corresponding to a data payload of 95.2 Gb/s error free transmission by using a 7% forward error correction (FEC) code. The signal is successfully recovered after 15 km of standard single mode fiber (SSMF) in a system limited by a 3 d......Short range optical data links are experiencing bandwidth limitations making it very challenging to cope with the growing data transmission capacity demands. Parallel optics appears as a valid short-term solution. It is, however, not a viable solution in the long-term because of its complex optical...... packaging. Therefore, increasing effort is now put into the possibility of exploiting higher order modulation formats with increased spectral efficiency and reduced optical transceiver complexity. As these type of links are based on intensity modulation and direct detection, modulation formats relying...

  4. NOVEL POLY-GLUTAMIC ACID FUNCTIONALIZED MICROFILTRATION MEMBRANES FOR SORPTION OF HEAVY METALS AT HIGH CAPACITY

    Science.gov (United States)

    Various sorbent/ion exchange materials have been reported in the literature for metal ion entrapment. We have developed a highly innovative and new approach to obtain high metal pick-up utilizing poly-amino acids (poly-L-glutamic acid, 14,000 MW) covalently attached to membrane p...

  5. High capacity V-based metal hydride electrodes for rechargeable batteries

    OpenAIRE

    Yang, Heng; Weadock, Nicholas J.; Tan, Hongjin; Fultz, Brent

    2017-01-01

    We report the successful development of Ti_(29)V_(62−x)Ni_9Cr_x (x = 0, 6, 12) body centered cubic metal hydride (MH) electrodes by addressing vanadium corrosion and dissolution in KOH solutions. By identifying oxygen as the primary source of corrosion and eliminating oxygen with an Ar-purged cell, the Cr-free Ti_(29)V_(62)Ni_9 alloy electrode achieved a maximum capacity of 594 mAh g^(-1), double the capacity of commercial AB_5 MH electrodes. With coin cells designed to minimize oxygen evolut...

  6. Development of high capacity, high rate lithium ion batteries utilizing metal fiber conductive additives

    Science.gov (United States)

    Ahn, Soonho; Kim, Youngduk; Kim, Kyung Joon; Kim, Tae Hyung; Lee, Hyungkeun; Kim, Myung H.

    As lithium ion cells dominate the battery market, the performance improvement is an utmost concern among developers and researchers. Conductive additives are routinely employed to enhance electrode conductivity and capacity. Carbon particulates—graphite or carbon black powders—are conventional and popular choices as conductive fillers. However, percolation requirements of particles demand significant volumetric content of impalpable, and thereby high area conductive fillers. As might be expected, the electrode active surface area escalates unnecessarily, resulting in overall increase in reaction with electrolytes and organic solvents. The increased reactions usually manifest as an irreversible loss of anode capacity, gradual oxidation and consumption of electrolyte on the cathode—which causes capacity decline during cycling—and an increased threat to battery safety by gas evolution and exothermic solvent oxidation. In this work we have utilized high aspect ratio, flexible, micronic metal fibers as low active area and high conductivity additives. The metal fibers appear well dispersed within the electrode and to satisfy percolation requirements very efficiently at very low volumetric content compared to conventional carbon-based conductive additives. Results from 18650-type cells indicate significant enhancements in electrode capacity and high rate capability while the irreversible capacity loss is negligible.

  7. Nitrogen Doped Macroporous Carbon as Electrode Materials for High Capacity of Supercapacitor

    Directory of Open Access Journals (Sweden)

    Yudong Li

    2017-01-01

    Full Text Available Nitrogen doped carbon materials as electrodes of supercapacitors have attracted abundant attention. Herein, we demonstrated a method to synthesize N-doped macroporous carbon materials (NMC with continuous channels and large size pores carbonized from polyaniline using multiporous silica beads as sacrificial templates to act as electrode materials in supercapacitors. By the nice carbonized process, i.e., pre-carbonization at 400 °C and then pyrolysis at 700/800/900/1000 °C, NMC replicas with high BET specific surface areas exhibit excellent stability and recyclability as well as superb capacitance behavior (~413 F ⋅ g−1 in alkaline electrolyte. This research may provide a method to synthesize macroporous materials with continuous channels and hierarchical pores to enhance the infiltration and mass transfer not only used as electrode, but also as catalyst somewhere micro- or mesopores do not work well.

  8. β-Cobalt sulfide nanoparticles decorated graphene composite electrodes for high capacity and power supercapacitors.

    Science.gov (United States)

    Qu, Baihua; Chen, Yuejiao; Zhang, Ming; Hu, Lingling; Lei, Danni; Lu, Bingan; Li, Qiuhong; Wang, Yanguo; Chen, Libao; Wang, Taihong

    2012-12-21

    Electrochemical supercapacitors have drawn much attention because of their high power and reasonably high energy densities. However, their performances still do not reach the demand of energy storage. In this paper β-cobalt sulfide nanoparticles were homogeneously distributed on a highly conductive graphene (CS-G) nanocomposite, which was confirmed by transmission electron microscopy analysis, and exhibit excellent electrochemical performances including extremely high values of specific capacitance (~1535 F g(-1)) at a current density of 2 A g(-1), high-power density (11.98 kW kg(-1)) at a discharge current density of 40 A g(-1) and excellent cyclic stability. The excellent electrochemical performances could be attributed to the graphene nanosheets (GNSs) which could maintain the mechanical integrity. Also the CS-G nanocomposite electrodes have high electrical conductivity. These results indicate that high electronic conductivity of graphene nanocomposite materials is crucial to achieving high power and energy density for supercapacitors.

  9. High-capacity nanostructured germanium-containing materials and lithium alloys thereof

    Energy Technology Data Exchange (ETDEWEB)

    Graetz, Jason A. (Upton, NY); Fultz, Brent T. (Pasadena, CA); Ahn, Channing (Pasadena, CA); Yazami, Rachid (Los Angeles, CA)

    2010-08-24

    Electrodes comprising an alkali metal, for example, lithium, alloyed with nanostructured materials of formula Si.sub.zGe.sub.(z-1), where 0

  10. High-capacity nanostructured germanium-containing materials and lithium alloys thereof

    Science.gov (United States)

    Graetz, Jason A.; Fultz, Brent T.; Ahn, Channing; Yazami, Rachid

    2010-08-24

    Electrodes comprising an alkali metal, for example, lithium, alloyed with nanostructured materials of formula Si.sub.zGe.sub.(z-1), where 0electrodes made from graphite. These electrodes are useful as anodes for secondary electrochemical cells, for example, batteries and electrochemical supercapacitors.

  11. CLSM: COUPLE LAYERED SECURITY MODEL A HIGH-CAPACITY DATA HIDING SCHEME USING WITH STEGANOGRAPHY

    Directory of Open Access Journals (Sweden)

    Cemal Kocak

    2017-03-01

    Full Text Available Cryptography and steganography are the two significant techniques used in secrecy of communications and in safe message transfer. In this study CLSM – Couple Layered Security Model is suggested which has a hybrid structure enhancing information security using features of cryptography and steganography. In CLSM system; the information which has been initially cryptographically encrypted is steganographically embedded in an image at the next step. The information is encrypted by means of a Text Keyword consisting of maximum 16 digits determined by the user in cryptography method. Similarly, the encrypted information is processed, during the embedding stage, using a 16 digit pin (I-PIN which is determined again by the user. The carrier images utilized in the study have been determined as 24 bit/pixel colour. Utilization of images in .jpeg, .tiff, .pnp format has also been provided. The performance of the CLSM method has been evaluated according to the objective quality measurement criteria of PSNR-dB (Peak Signal-to-Noise Ratio and SSIM (Structural Similarity Index. In the study, 12 different sized information between 1000 and 609,129 bits were embedded into images. Between 34.14 and 65.8 dB PSNR values and between 0.989 and 0.999 SSIM values were obtained. CLSM showed better results compared to Pixel Value Differencing (PVD method, Simulated Annealing (SA Algorithm and Mix column transform based on irreducible polynomial mathematics methods.

  12. Development and characterization of a high capacity lithium/thionyl chloride battery

    Science.gov (United States)

    Boyle, Gerald H.; Goebel, Franz

    A 30 V lithium/thionyl chloride battery with 320 Ah capacity capable of operating at currents of 14 to 75 A has been developed and tested over a temperature range from 15 to 71 °C. The 81 lb battery consists of nine series connected cylindrical cells in a three-by-three arrangement within an aluminum case. The cells are of a parallel disc electrode design with a total active surface area of 10 200 cm 2. Cells and batteries have each been tested for safety, performance and to a space environment. The battery has clearly performed in excess of the specification requirements. The cell design is very adaptable to many battery design requirements.

  13. Development and characterization of a high capacity lithium/thionyl chloride battery

    Energy Technology Data Exchange (ETDEWEB)

    Boyle, G.H. [Yardney Technical Products, Inc., Pawcatuck, CT (United States); Goebel, F. [Yardney Technical Products, Inc., Pawcatuck, CT (United States)

    1995-04-01

    A 30 V lithium/thionyl chloride battery with 320 Ah capacity capable of operating at currents of 14 to 75 A has been developed and tested over a temperature range from 15 to 71 C. The 81 lb battery consists of nine series connected cylindrical cells in a three-by-three arrangement within an aluminum case. The cells are of a parallel disc electrode design with a total active surface area of 10 200 cm{sup 2}. Cells and batteries have each been tested for safety, performance and to a space environment. The battery has clearly performed in excess of the specification requirements. The cell design is very adaptable to many battery design requirements. (orig.)

  14. Durability testing of the high-capacity GA-4/GA-9 trailer

    International Nuclear Information System (INIS)

    Zimmer, A.; Lyon, T.

    1995-01-01

    GA designed trailers to transport the GA-4 and GA-9 LWT from-reactor spent nuclear fuel shipping casks. GA designed and fabricated the GA-9 trailer to ANSI N14.30 requirements and is now performing a durability test at the AlliedSignal Automotive Proving Grounds. The trailer, simulated cask and tractor. The test program objective is to evaluate and improve, as necessary, the trailer's durability, reliability and performance

  15. Robust, High Capacity, High Power Lithium Ion Batteries for Space Systems, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Lithium ion battery technology provides the highest energy density of all rechargeable battery technologies available today. However, the majority of the research...

  16. Mouse lung contains endothelial progenitors with high capacity to form blood and lymphatic vessels

    Directory of Open Access Journals (Sweden)

    Barleon Bernhard

    2010-07-01

    Full Text Available Abstract Background Postnatal endothelial progenitor cells (EPCs have been successfully isolated from whole bone marrow, blood and the walls of conduit vessels. They can, therefore, be classified into circulating and resident progenitor cells. The differentiation capacity of resident lung endothelial progenitor cells from mouse has not been evaluated. Results In an attempt to isolate differentiated mature endothelial cells from mouse lung we found that the lung contains EPCs with a high vasculogenic capacity and capability of de novo vasculogenesis for blood and lymph vessels. Mouse lung microvascular endothelial cells (MLMVECs were isolated by selection of CD31+ cells. Whereas the majority of the CD31+ cells did not divide, some scattered cells started to proliferate giving rise to large colonies (> 3000 cells/colony. These highly dividing cells possess the capacity to integrate into various types of vessels including blood and lymph vessels unveiling the existence of local microvascular endothelial progenitor cells (LMEPCs in adult mouse lung. EPCs could be amplified > passage 30 and still expressed panendothelial markers as well as the progenitor cell antigens, but not antigens for immune cells and hematopoietic stem cells. A high percentage of these cells are also positive for Lyve1, Prox1, podoplanin and VEGFR-3 indicating that a considerabe fraction of the cells are committed to develop lymphatic endothelium. Clonogenic highly proliferating cells from limiting dilution assays were also bipotent. Combined in vitro and in vivo spheroid and matrigel assays revealed that these EPCs exhibit vasculogenic capacity by forming functional blood and lymph vessels. Conclusion The lung contains large numbers of EPCs that display commitment for both types of vessels, suggesting that lung blood and lymphatic endothelial cells are derived from a single progenitor cell.

  17. A Blind High-Capacity Wavelet-Based Steganography Technique for Hiding Images into other Images

    Directory of Open Access Journals (Sweden)

    HAMAD, S.

    2014-05-01

    Full Text Available The flourishing field of Steganography is providing effective techniques to hide data into different types of digital media. In this paper, a novel technique is proposed to hide large amounts of image data into true colored images. The proposed method employs wavelet transforms to decompose images in a way similar to the Human Visual System (HVS for more secure and effective data hiding. The designed model can blindly extract the embedded message without the need to refer to the original cover image. Experimental results showed that the proposed method outperformed all of the existing techniques not only imperceptibility but also in terms of capacity. In fact, the proposed technique showed an outstanding performance on hiding a secret image whose size equals 100% of the cover image while maintaining excellent visual quality of the resultant stego-images.

  18. A high capacity text steganography scheme based on LZW compression and color coding

    Directory of Open Access Journals (Sweden)

    Aruna Malik

    2017-02-01

    Full Text Available In this paper, capacity and security issues of text steganography have been considered by employing LZW compression technique and color coding based approach. The proposed technique uses the forward mail platform to hide the secret data. This algorithm first compresses secret data and then hides the compressed secret data into the email addresses and also in the cover message of the email. The secret data bits are embedded in the message (or cover text by making it colored using a color coding table. Experimental results show that the proposed method not only produces a high embedding capacity but also reduces computational complexity. Moreover, the security of the proposed method is significantly improved by employing stego keys. The superiority of the proposed method has been experimentally verified by comparing with recently developed existing techniques.

  19. Process for the generation of high capacity pulses from an inductive energy storage device

    International Nuclear Information System (INIS)

    Maier, F.; Maier, S.

    1984-01-01

    An inductive storage circuit for generating high voltage pulses includes a quenching circuit and a discharge circuit each connected in parallel with a storage inductor. One branch of the quenching circuit includes a quenching capacitor and one branch of the discharge circuit includes a resistor and a diode in series. These two branches have a common junction, to which is connected a quenching thyristor that forms the second branch of each of the quenching and discharge circuits. Thus, the quenching thyristor is in series with each of the quenching capacitor and the discharge resistor

  20. High capacity electrode materials for batteries and process for their manufacture

    Science.gov (United States)

    Johnson, Christopher S.; Xiong, Hui; Rajh, Tijana; Shevchenko, Elena; Tepavcevic, Sanja

    2018-04-03

    The present invention provides a nanostructured metal oxide material for use as a component of an electrode in a lithium-ion or sodium-ion battery. The material comprises a nanostructured titanium oxide or vanadium oxide film on a metal foil substrate, produced by depositing or forming a nanostructured titanium dioxide or vanadium oxide material on the substrate, and then charging and discharging the material in an electrochemical cell from a high voltage in the range of about 2.8 to 3.8 V, to a low voltage in the range of about 0.8 to 1.4 V over a period of about 1/30 of an hour or less. Lithium-ion and sodium-ion electrochemical cells comprising electrodes formed from the nanostructured metal oxide materials, as well as batteries formed from the cells, also are provided.

  1. A biomimetic high-capacity phenazine-based anolyte for aqueous organic redox flow batteries

    Science.gov (United States)

    Hollas, Aaron; Wei, Xiaoliang; Murugesan, Vijayakumar; Nie, Zimin; Li, Bin; Reed, David; Liu, Jun; Sprenkle, Vincent; Wang, Wei

    2018-06-01

    Aqueous soluble organic (ASO) redox-active materials have recently attracted significant attention as alternatives to traditional transition metal ions in redox flow batteries (RFB). However, reported reversible capacities of ASO are often substantially lower than their theoretical values based on the reported maximum solubilities. Here, we describe a phenazine-based ASO compound with an exceptionally high reversible capacity that exceeds 90% of its theoretical value. By strategically modifying the phenazine molecular structure, we demonstrate an increased solubility from near-zero with pristine phenazine to as much as 1.8 M while also shifting its redox potential by more than 400 mV. An RFB based on a phenazine derivative (7,8-dihydroxyphenazine-2-sulfonic acid) at its near-saturation concentration exhibits an operating voltage of 1.4 V with a reversible anolyte capacity of 67 Ah l-1 and a capacity retention of 99.98% per cycle over 500 cycles.

  2. Frequency Assignment for Joint Aerial Layer Network High-Capacity Backbone

    Science.gov (United States)

    2017-08-11

    Two Frequency Assignment Problems (FAPs) are considered in this work, which are called MMC-FAP and MS-FAP. MMC-FAP is to minimize the frequency usage... minimize the frequency span in both frequency bands. By exploiting problem-specific properties, MMC-FAP can be formulated as a Mixed Integer Linear...considered for JALN HCB. The first FAP problem, called MMC- FAP, is to minimize the frequency usage of the most congested aerial platform in both

  3. Carbon−Silicon Core−Shell Nanowires as High Capacity Electrode for Lithium Ion Batteries

    KAUST Repository

    Cui, Li-Feng

    2009-09-09

    We introduce a novel design of carbon-silicon core-shell nanowires for high power and long life lithium battery electrodes. Amorphous silicon was coated onto carbon nanofibers to form a core-shell structure and the resulted core-shell nanowires showed great performance as anode material. Since carbon has a much smaller capacity compared to silicon, the carbon core experiences less structural stress or damage during lithium cycling and can function as a mechanical support and an efficient electron conducting pathway. These nanowires have a high charge storage capacity of ∼2000 mAh/g and good cycling life. They also have a high Coulmbic efficiency of 90% for the first cycle and 98-99.6% for the following cycles. A full cell composed of LiCoO2 cathode and carbon-silicon core-shell nanowire anode is also demonstrated. Significantly, using these core-shell nanowires we have obtained high mass loading and an area capacity of ∼4 mAh/cm2, which is comparable to commercial battery values. © 2009 American Chemical Society.

  4. Magnesium stannide as a high-capacity anode for magnesium-ion batteries

    Science.gov (United States)

    Nguyen, Dan-Thien; Song, Seung-Wan

    2017-11-01

    Driven by the limited global resources of lithium, magnesium metal batteries are considered as potential energy storage systems. The battery chemistry of magnesium metal anode, however, limits the selection of electrolytes, cathode materials and working temperature, making the realization of magnesium metal batteries complicated. Herein, we report the development of a new magnesium-insertion anode, magnesium stannide (Mg2Sn), and demonstrate reversible electrochemical Mg2+-extraction and insertion of Mg2Sn anode at 0.2 V versus Mg, delivering discharge capacity of 270 mAhg-1 in a half-cell with the electrolyte of PhMgCl/THF and enabling of room temperature magnesium-ion batteries with Mg2Sn anode combined with Mg-free oxide cathode and conventional-type electrolyte of Mg(TFSI)2/diglyme. The combination of Mg2Sn anode with various cathodes and electrolytes holds great promise for enabling room temperature magnesium-ion batteries.

  5. Quad-Polarization Transmission for High-Capacity IM/DD Links

    DEFF Research Database (Denmark)

    Estaran Tolosa, Jose Manuel; Castaneda, Mario A. Usuga; Porto da Silva, Edson

    2014-01-01

    We report the first experimental demonstration of IM/DD links usi ng four states of polarization. Fiber - Induced polarization rotation is compensated with a simple tracking algorithm operating on the Stokes space. The principle is prove n at 128 Gb/s over 2 - km SSMF......We report the first experimental demonstration of IM/DD links usi ng four states of polarization. Fiber - Induced polarization rotation is compensated with a simple tracking algorithm operating on the Stokes space. The principle is prove n at 128 Gb/s over 2 - km SSMF...

  6. Quaternary Polarization-Multiplexed Subsystem for High-Capacity IM/DD Optical Data Links

    DEFF Research Database (Denmark)

    Estaran Tolosa, Jose Manuel; Usuga Castaneda, Mario A.; Porto da Silva, Edson

    2015-01-01

    We demonstrate for the first time an intensitymodulated direct-detection link using four states of polarization. The four data-independent tributaries are each assigned distinct states of polarization to enable the receiver to separate the signals. Polarization rotation due to propagation over op...

  7. Nanoscale zinc-based metal-organic framework with high capacity for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Changdong [Changzhou University, School of Petrochemical Engineering, Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, and Advanced Catalysis and Green Manufacturing Collaborative Innovation Center (China); Gao, Yuanrui; Liu, Lili [Shanghai University, Department of Chemistry, College of Science (China); Song, Yidan; Wang, Xianmei [Changzhou University, School of Petrochemical Engineering, Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, and Advanced Catalysis and Green Manufacturing Collaborative Innovation Center (China); Liu, Hong-Jiang, E-mail: liuhj@shu.edu.cn [Shanghai University, Department of Chemistry, College of Science (China); Liu, Qi, E-mail: liuqi62@163.com [Changzhou University, School of Petrochemical Engineering, Jiangsu Key Laboratory of Advanced Catalytic Materials and Technology, and Advanced Catalysis and Green Manufacturing Collaborative Innovation Center (China)

    2016-12-15

    Layered zinc-based metal-organic framework ([Zn(4,4′-bpy)(tfbdc)(H{sub 2}O){sub 2}], Zn-LMOF) nanosheets were synthesized by a facile hydrothermal method (4,4′-bpy = 4,4′-bipyridine, H{sub 2}tfbdc = tetrafluoroterephthalic acid). The materials were characterized by IR spectrum, elemental analysis, thermogravimetric analysis, powder X-ray diffraction, transmission electron microscope (TEM), scanning electron microscope (SEM), and the Brunauer–Emmett–Teller (BET) surface. When the Zn-LMOF nanosheets with the thickness of about 24 ± 8 nm were used as an anode material of lithium-ion batteries, not only the Zn-LMOF electrode shows a high reversible capacity, retaining 623 mAh g{sup −1} after 100 cycles at a current density of 50 mA g{sup −1} but also exhibits an excellent cyclic stability and a higher rate performance.

  8. High-capacity quantum key distribution via hyperentangled degrees of freedom

    International Nuclear Information System (INIS)

    Simon, David S; Sergienko, Alexander V

    2014-01-01

    Quantum key distribution (QKD) has long been a promising area for the application of quantum effects in solving real-world problems. However, two major obstacles have stood in the way of its widespread application: low secure key generation rates and short achievable operating distances. In this paper, a new physical mechanism for dealing with the first of these problems is proposed: the interplay between different degrees of freedom in a hyperentangled system (parametric down-conversion) is used to increase the Hilbert space dimension available for key generation while maintaining security. Polarization-based Bell tests provide security checking, while orbital angular momentum (OAM) and total angular momentum (TAM) provide a higher key generation rate. Whether to measure TAM or OAM is decided randomly in each trial. The concurrent noncommutativity of TAM with OAM and polarization provides the physical basis for quantum security. TAM measurements link polarization to OAM, so that if the legitimate participants measure OAM while the eavesdropper measures TAM (or vice-versa), then polarization entanglement is lost, revealing the eavesdropper. In contrast to other OAM-based QKD methods, complex active switching between OAM bases is not required; instead, passive switching by beam splitters combined with much simpler active switching between polarization bases makes implementation at high OAM more practical. (paper)

  9. High-Capacity Multi-Core Fibers for Space-Division Multiplexing

    DEFF Research Database (Denmark)

    Ye, Feihong

    The transmission capacity of the present optical fiber communication systems based on time division multiplexing (TDM) and wavelength-division multiplexing (WDM) using single-mode fibers (SMFs) is reaching its limit of around 100 Tbit/s per fiber due to the fiber nonlinearities, fiber fuse...... phenomenon and the optical amplifier bandwidth. To meet the ever increasing global data traffic growth and to overcome the looming capacity crunch, a new multiplexing technology using new optical fibers is urgently needed. Space-division multiplexing (SDM) is a promising scheme to overcome the capacity limit...... of the present SMF-based systems. Among the proposed SDM schemes, the one based on uncoupled multi-core fibers (MCFs) having multiple cores in a mutual cladding has proven effective in substantially increasing the transmission capacity per fiber with least system complexity as demonstrated in several state...

  10. Thermal management for high-capacity large format Li-ion batteries

    Science.gov (United States)

    Wang, Hsin; Kepler, Keith Douglas; Pannala, Sreekanth; Allu, Srikanth

    2017-05-30

    A lithium ion battery includes a cathode in electrical and thermal connection with a cathode current collector. The cathode current collector has an electrode tab. A separator is provided. An anode is in electrical and thermal connection with an anode current collector. The anode current collector has an electrode tab. At least one of the cathode current collector and the anode current collector comprises a thermal tab for heat transfer with the at least one current collector. The thermal tab is separated from the electrode tab. A method of operating a battery is also disclosed.

  11. Lithium alloys and metal oxides as high-capacity anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Liang, Chu; Gao, Mingxia; Pan, Hongge; Liu, Yongfeng; Yan, Mi

    2013-01-01

    Highlights: •Progress in lithium alloys and metal oxides as anode materials for lithium-ion batteries is reviewed. •Electrochemical characteristics and lithium storage mechanisms of lithium alloys and metal oxides are summarized. •Strategies for improving electrochemical lithium storage properties of lithium alloys and metal oxides are discussed. •Challenges in developing lithium alloys and metal oxides as commercial anodes for lithium-ion batteries are pointed out. -- Abstract: Lithium alloys and metal oxides have been widely recognized as the next-generation anode materials for lithium-ion batteries with high energy density and high power density. A variety of lithium alloys and metal oxides have been explored as alternatives to the commercial carbonaceous anodes. The electrochemical characteristics of silicon, tin, tin oxide, iron oxides, cobalt oxides, copper oxides, and so on are systematically summarized. In this review, it is not the scope to retrace the overall studies, but rather to highlight the electrochemical performances, the lithium storage mechanism and the strategies in improving the electrochemical properties of lithium alloys and metal oxides. The challenges and new directions in developing lithium alloys and metal oxides as commercial anodes for the next-generation lithium-ion batteries are also discussed

  12. Carbon−Silicon Core−Shell Nanowires as High Capacity Electrode for Lithium Ion Batteries

    KAUST Repository

    Cui, Li-Feng; Yang, Yuan; Hsu, Ching-Mei; Cui, Yi

    2009-01-01

    We introduce a novel design of carbon-silicon core-shell nanowires for high power and long life lithium battery electrodes. Amorphous silicon was coated onto carbon nanofibers to form a core-shell structure and the resulted core-shell nanowires

  13. Technology Assessment of High Capacity Data Storage Systems: Can We Avoid a Data Survivability Crisis?

    Science.gov (United States)

    Halem, Milton

    1999-01-01

    In a recent address at the California Science Center in Los Angeles, Vice President Al Gore articulated a Digital Earth Vision. That vision spoke to developing a multi-resolution, three-dimensional visual representation of the planet into which we can roam and zoom into vast quantities of embedded geo-referenced data. The vision was not limited to moving through space, but also allowing travel over a time-line, which can be set for days, years, centuries, or even geological epochs. A working group of Federal Agencies, developing a coordinated program to implement the Vice President's vision, developed the definition of the Digital Earth as a visual representation of our planet that enables a person to explore and interact with the vast amounts of natural and cultural geo-referenced information gathered about the Earth. One of the challenges identified by the agencies was whether the technology existed that would be available to permanently store and deliver all the digital data that enterprises might want to save for decades and centuries. Satellite digital data is growing by Moore's Law as is the growth of computer generated data. Similarly, the density of digital storage media in our information-intensive society is also increasing by a factor of four every three years. The technological bottleneck is that the bandwidth for transferring data is only growing at a factor of four every nine years. This implies that the migration of data to viable long-term storage is growing more slowly. The implication is that older data stored on increasingly obsolete media are at considerable risk if they cannot be continuously migrated to media with longer life times. Another problem occurs when the software and hardware systems for which the media were designed are no longer serviced by their manufacturers. Many instances exist where support for these systems are phased out after mergers or even in going out of business. In addition, survivability of older media can suffer from physical breakdown of components (e.g. tapes simply lose their magnetic properties after a long time in storage). As a result, a potential data survivability crisis is emerging. The scale of the crisis is comparable to that facing the Social Security System. Sometime in one or two decades, the exponential growth of data will become so great that many enterprises will not be able to migrate through their data to more permanent media during the lifetime of the media on which it resides. This will result in significant losses of data and their resultant impacts. To avoid this crisis, we need to plan and devote greater financial and intellectual resources are needed for the development and refinement of new storage media and migration technologies in order to preserve all data any organization determines worth saving permanently. This talk will explore technological solutions and suggested recommendations to address this technological data crisis.

  14. Technology Assessment of High Capacity Data Storage Systems: Can We Avoid a Data Survivability Crisis

    Science.gov (United States)

    Halem, M.; Shaffer, F.; Palm, N.; Salmon, E.; Raghavan, S.; Kempster, L.

    1998-01-01

    The density of digital storage media in our information-intensive society increases by a factor of four every three years, while the rate at which this data can be migrated to viable long-term storage has been increasing by a factor of only four every nine years. Meanwhile, older data stored on increasingly obsolete media, are at considerable risk. When the systems for which the media were designed are no longer serviced by their manufacturers (many of whom are out of business), the data will no longer be accessible. In some cases, older media suffer from a physical breakdown of components - tapes simply lose their magnetic properties after a long time in storage. The scale of the crisis is compatible to that facing the Social Security System. Greater financial and intellectual resources to the development and refinement of new storage media and migration technologies in order to preserve as much data as possible.

  15. 75 FR 10860 - Preparation of an Alternatives Analysis and Environmental Impact Statement for High Capacity...

    Science.gov (United States)

    2010-03-09

    ..., social, and economic impacts to be analyzed; and (f) the evaluation approach to be used to select the LPA... justice, aesthetics, air quality, noise and vibration, wildlife, vegetation, threatened and endangered...

  16. Approach for implementing burnup credit in high-capacity truck casks

    International Nuclear Information System (INIS)

    Boshoven, J.; Hopf, J.; Su, S.

    1991-01-01

    General Atomics (GA) will be submitting an application for certification to the US Nuclear Regulatory Commission (NRC) for the GA-4 and GA-9 Casks in 1992. To maintain a capacity of four pressurized-water-reactor (PWR) spent fuel assemblies, the GA-4 Cask uses burnup credit as part of the criticality control for the higher enrichments. Using the US Department of Energy (DOE) Burnup Credit Program as a basis, GA presents here an approach to burnup credit analysis to be included in the Safety Analysis Report for Packaging (SARP). 6 refs., 2 figs., 5 tabs

  17. Hierarchically structured lithium titanate for ultrafast charging in long-life high capacity batteries

    Science.gov (United States)

    Odziomek, Mateusz; Chaput, Frédéric; Rutkowska, Anna; Świerczek, Konrad; Olszewska, Danuta; Sitarz, Maciej; Lerouge, Frédéric; Parola, Stephane

    2017-05-01

    High-performance Li-ion batteries require materials with well-designed and controlled structures on nanometre and micrometre scales. Electrochemical properties can be enhanced by reducing crystallite size and by manipulating structure and morphology. Here we show a method for preparing hierarchically structured Li4Ti5O12 yielding nano- and microstructure well-suited for use in lithium-ion batteries. Scalable glycothermal synthesis yields well-crystallized primary 4-8 nm nanoparticles, assembled into porous secondary particles. X-ray photoelectron spectroscopy reveals presence of Ti+4 only; combined with chemical analysis showing lithium deficiency, this suggests oxygen non-stoichiometry. Electron microscopy confirms hierarchical morphology of the obtained material. Extended cycling tests in half cells demonstrates capacity of 170 mAh g-1 and no sign of capacity fading after 1,000 cycles at 50C rate (charging completed in 72 s). The particular combination of nanostructure, microstructure and non-stoichiometry for the prepared lithium titanate is believed to underlie the observed electrochemical performance of material.

  18. School Improvement in High-Capacity Schools: Educational Leadership and Living-Systems Ontology

    Science.gov (United States)

    Mitchell, Coral; Sackney, Larry

    2016-01-01

    Although school improvement continues to present as an unresolved educational problem, the required changes are relatively straightforward. Essentially, schools need to be retooled with students' experiences and high-quality instruction at the center of the design. In this article, we present the findings of research into the leadership of…

  19. The European BOOM project :silicon photonics for high-capacity optical packet routers

    NARCIS (Netherlands)

    Stampoulidis, L.; Vyrsokinos, K.; Voigt, K.; Zimmermann, L.; Gomez-Agis, F.; Dorren, H.J.S.; Sheng, Z.; Thourhout, Van D.; Moerl, L.; Kreissl, J.; Sedighi, B.; Scheytt, J.C.; Pagano, A.; Riccardi, E.

    2010-01-01

    During the past years, monolithic integration in InP has been the driving force for the realization of integrated photonic routing systems. The advent of silicon as a basis for cost-effective integration and its potential blend with III–V material is now opening exciting opportunities for the

  20. High-capacity conductive nanocellulose paper sheets for electrochemically controlled extraction of DNA oligomers.

    Directory of Open Access Journals (Sweden)

    Aamir Razaq

    Full Text Available Highly porous polypyrrole (PPy-nanocellulose paper sheets have been evaluated as inexpensive and disposable electrochemically controlled three-dimensional solid phase extraction materials. The composites, which had a total anion exchange capacity of about 1.1 mol kg(-1, were used for extraction and subsequent release of negatively charged fluorophore tagged DNA oligomers via galvanostatic oxidation and reduction of a 30-50 nm conformal PPy layer on the cellulose substrate. The ion exchange capacity, which was, at least, two orders of magnitude higher than those previously reached in electrochemically controlled extraction, originated from the high surface area (i.e. 80 m(2 g(-1 of the porous composites and the thin PPy layer which ensured excellent access to the ion exchange material. This enabled the extractions to be carried out faster and with better control of the PPy charge than with previously employed approaches. Experiments in equimolar mixtures of (dT(6, (dT(20, and (dT(40 DNA oligomers showed that all oligomers could be extracted, and that the smallest oligomer was preferentially released with an efficiency of up to 40% during the reduction of the PPy layer. These results indicate that the present material is very promising for the development of inexpensive and efficient electrochemically controlled ion-exchange membranes for batch-wise extraction of biomolecules.