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Sample records for hotel sekonomit na

  1. 54. VIEW LOOKING NORTHEAST AT DENNIS HOTEL, BLENHEIM HOTEL AND ...

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

    54. VIEW LOOKING NORTHEAST AT DENNIS HOTEL, BLENHEIM HOTEL AND MARLBOROUGH HOTEL (LEFT TO RIGHT) - Marlborough, Blenheim & Dennis Hotels (aerial views), Between Park Place, Michigan Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  2. 57. VIEW LOOKING NORTH OF DENNIS HOTEL. BLENHEIM HOTEL IS ...

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

    57. VIEW LOOKING NORTH OF DENNIS HOTEL. BLENHEIM HOTEL IS PARTLY VISABLE TO THE RIGHT; SHELBOURNE HOTEL IS PARTLY VISABLE TO THE LEFT - Marlborough, Blenheim & Dennis Hotels (aerial views), Between Park Place, Michigan Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  3. 66. VIEW LOOKING NORTH AT THE MARLBOROUGH HOTEL. BLENHEIM HOTEL ...

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

    66. VIEW LOOKING NORTH AT THE MARLBOROUGH HOTEL. BLENHEIM HOTEL IS PARTIALLY VIASBLE TO THE LEFT. CLARIDGE HOTEL IS VISABLE TO THE RIGHT - Marlborough, Blenheim & Dennis Hotels (aerial views), Between Park Place, Michigan Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  4. 41. VIEW LOOKING NORTHWEST AT THE DENNIS HOTEL, BLENHEIM HOTEL ...

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

    41. VIEW LOOKING NORTHWEST AT THE DENNIS HOTEL, BLENHEIM HOTEL AND MARLBOROUGH HOTEL (LEFT TO RIGHT). CLARIDGE HOTEL IS PARTLY VISABLE TO THE RIGHT - Marlborough, Blenheim & Dennis Hotels (aerial views), Between Park Place, Michigan Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  5. The Infinite Hotel

    ERIC Educational Resources Information Center

    Wanko, Jeffrey J.

    2009-01-01

    This article provides a historical context for the debate between Georg Cantor and Leopold Kronecker regarding the cardinality of different infinities and incorporates the short story "Welcome to the Hotel Infinity," which uses the analogy of a hotel with an infinite number of rooms to help explain this concept. Wanko makes use of this history and…

  6. Crime wave in hotels.

    PubMed

    1998-04-03

    A National Development and Research Institutes study of New York's residential hotels, housing 400 AIDS patients, found rampant criminal activity. The 113-page report, commissioned by Mayor Guiliani, found prostitution, loan sharking, extortion, and theft to be commonplace, some of it perpetrated by hotel managers and employees. The unsafe conditions force some residents to miss medical treatments or drug rehabilitation because they are afraid to leave their rooms.

  7. 1. EAST FACADE OF THE MARCUS DALY HOTEL. THE HOTEL ...

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

    1. EAST FACADE OF THE MARCUS DALY HOTEL. THE HOTEL WAS CONSTRUCTED IN A U SHAPE, WITH THE ENTRANCE ARCADE FORMING THE FORTH SIDE OF THE RECTANGLE - Anaconda Historic District, Marcus Daly Hotel, 200-208 Main Street, Anaconda, Deer Lodge County, MT

  8. 52. VIEW LOOKING EAST WITH THE MARLBOROUGH HOTEL, BLENHEIM HOTEL ...

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

    52. VIEW LOOKING EAST WITH THE MARLBOROUGH HOTEL, BLENHEIM HOTEL AND THE DENNIS HI=OTEL (TOP TO BOTTOM) IN THE CENTER OF THE PHOTOGRAPH - Marlborough, Blenheim & Dennis Hotels (aerial views), Between Park Place, Michigan Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  9. Quantum Hilbert Hotel.

    PubMed

    Potoček, Václav; Miatto, Filippo M; Mirhosseini, Mohammad; Magaña-Loaiza, Omar S; Liapis, Andreas C; Oi, Daniel K L; Boyd, Robert W; Jeffers, John

    2015-10-16

    In 1924 David Hilbert conceived a paradoxical tale involving a hotel with an infinite number of rooms to illustrate some aspects of the mathematical notion of "infinity." In continuous-variable quantum mechanics we routinely make use of infinite state spaces: here we show that such a theoretical apparatus can accommodate an analog of Hilbert's hotel paradox. We devise a protocol that, mimicking what happens to the guests of the hotel, maps the amplitudes of an infinite eigenbasis to twice their original quantum number in a coherent and deterministic manner, producing infinitely many unoccupied levels in the process. We demonstrate the feasibility of the protocol by experimentally realizing it on the orbital angular momentum of a paraxial field. This new non-Gaussian operation may be exploited, for example, for enhancing the sensitivity of NOON states, for increasing the capacity of a channel, or for multiplexing multiple channels into a single one.

  10. Quantum Hilbert Hotel

    NASA Astrophysics Data System (ADS)

    Potoček, Václav; Miatto, Filippo M.; Mirhosseini, Mohammad; Magaña-Loaiza, Omar S.; Liapis, Andreas C.; Oi, Daniel K. L.; Boyd, Robert W.; Jeffers, John

    2015-10-01

    In 1924 David Hilbert conceived a paradoxical tale involving a hotel with an infinite number of rooms to illustrate some aspects of the mathematical notion of "infinity." In continuous-variable quantum mechanics we routinely make use of infinite state spaces: here we show that such a theoretical apparatus can accommodate an analog of Hilbert's hotel paradox. We devise a protocol that, mimicking what happens to the guests of the hotel, maps the amplitudes of an infinite eigenbasis to twice their original quantum number in a coherent and deterministic manner, producing infinitely many unoccupied levels in the process. We demonstrate the feasibility of the protocol by experimentally realizing it on the orbital angular momentum of a paraxial field. This new non-Gaussian operation may be exploited, for example, for enhancing the sensitivity of NOON states, for increasing the capacity of a channel, or for multiplexing multiple channels into a single one.

  11. An Imaginary Community--Hotel.

    ERIC Educational Resources Information Center

    Allan, Jan

    1969-01-01

    An English class at Newtyle Secondary School, Scotland, spent four periods a week for 6 weeks on an anthological project entitled "hotel". Students assumed roles in an imaginary hotel community, wrote advertisements, brochures, and business letters, and participated in interviews, discussions, and dramatizations of specific hotel problems. Besides…

  12. [Deaths in hotels].

    PubMed

    Risse, Manfred; Weilbächer, Nadine; Birngruber, Christoph; Verhoff, Marcel A

    2010-01-01

    There are no verified statistics about deaths occurring in hotels, and only a few cases have been described in the literature. A recent case induced us to conduct a systematic search for deaths in hotels in the autopsy reports of the Institute of Legal Medicine in Giessen for the period from 1968 to 2009. This search yielded 22 evaluable cases in which persons had been found dead or had died in hotels. Data evaluated in the study were sex and age of the deceased, reason for the stay in the hotel and cause of death. Among the deaths, 18 were males and 4 females and the average age was 41 and 40 years respectively. 6 of the male guests had died from a natural and 10 from a non-natural cause. In the remaining two cases, the cause of death could not be determined, but as there was no evidence that another party had been involved, the cases were not further investigated. Of the 4 female guests, 3 had died of a natural cause; in one case, the cause of death remained unclear even after morphological and toxicological investigations. Surprisingly, a third of the men were found to be temporarily living in hotels due to social circumstances. This was not true for any of the women. Our retrospective analysis is based on a comparatively small number of deaths in what were mostly hotels in small to medium-sized towns. Interestingly, the gender ratio of 18:4 for deceased men and women was significantly higher than the usual gender ratio of 2:1 found for forensic autopsies. To be able to draw further conclusions, a greater number of cases would have to be analysed, for example by recruiting additional case files from other institutes of legal medicine. This would also open up the option of investigating possible regional variations.

  13. 27 CFR 31.82 - Hotels.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2012-04-01 2012-04-01 false Hotels. 31.82 Section 31... Same Premises § 31.82 Hotels. The proprietor of a hotel who conducts the sale of liquors throughout the hotel premises is only required to register under this part for one place. For example, different...

  14. 27 CFR 31.82 - Hotels.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2014-04-01 2014-04-01 false Hotels. 31.82 Section 31... Same Premises § 31.82 Hotels. The proprietor of a hotel who conducts the sale of liquors throughout the hotel premises is only required to register under this part for one place. For example, different...

  15. 27 CFR 31.82 - Hotels.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2013-04-01 2013-04-01 false Hotels. 31.82 Section 31... Same Premises § 31.82 Hotels. The proprietor of a hotel who conducts the sale of liquors throughout the hotel premises is only required to register under this part for one place. For example, different...

  16. 27 CFR 31.82 - Hotels.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2011-04-01 2011-04-01 false Hotels. 31.82 Section 31... Same Premises § 31.82 Hotels. The proprietor of a hotel who conducts the sale of liquors throughout the hotel premises is only required to register under this part for one place. For example, different...

  17. 27 CFR 31.82 - Hotels.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Hotels. 31.82 Section 31... Same Premises § 31.82 Hotels. The proprietor of a hotel who conducts the sale of liquors throughout the hotel premises is only required to register under this part for one place. For example, different...

  18. Towards Universal Design Hotels in Denmark.

    PubMed

    Grangaard, Sidse

    2016-01-01

    Based on the research project 'Accessible Hotel Rooms' that studies the balance between the experience of supply and demand regarding accessibility features in Danish hotel rooms, this paper demonstrates factors having an influence on Universal Design hotels in Denmark. The research project was financed by the Danish Transport and Construction Agency. Different notions in the hotel sector of the current supply and demand for Universal Design hotel rooms are identified, as well as future demand. Despite supplying accessible rooms, some hotels do not advertise their accessibility features on their website. There exists an attitude in the hotel sector that functions as a barrier for Universal Design: if there are enough guests, for example business travellers, then why market the hotel on Universal Design? The paper points out the coherence between the understanding of the users and the view of demand. Another important factor is Corporate Social Responsibility, which can be regarded as a strategy or platform towards Universal Design hotels.

  19. 27. VIEW LOOKING NORTH AT ROOFS OF DENNIS HOTEL AND ...

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

    27. VIEW LOOKING NORTH AT ROOFS OF DENNIS HOTEL AND BLENHEIM HOTEL. MARLBOROUGH HOTEL IS PARTLY VISIBLE TO THE RIGHT - Marlborough, Blenheim & Dennis Hotels (aerial views), Between Park Place, Michigan Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  20. 6. VIEW LOOKING NORTH TO NORTHEAST OF DENNIS HOTEL, BLENHEIM ...

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

    6. VIEW LOOKING NORTH TO NORTHEAST OF DENNIS HOTEL, BLENHEIM HOTEL AND MARLBOROUGH HOTEL (LEFT TO RIGHT) IN THE CENTER OF THE PHOTO - Marlborough, Blenheim & Dennis Hotels (aerial views), Between Park Place, Michigan Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  1. Hotels Make Room for Fitness.

    ERIC Educational Resources Information Center

    Koszuta, Laurie Einstein

    1986-01-01

    Hotels, in hopes of gaining a competitive edge, are offering workout rooms, exercise equipment, fitness trails, and jogging tracks, but no standards have been set for safety of the facilities or staff preparedness in exercise screening, equipment use, injury prevention, or first aid. (MT)

  2. CONTEXTUAL VIEW FROM HOTEL; HAMILTON BUNGALOW IN FOREGROUND; BUNGALOW NO. ...

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

    CONTEXTUAL VIEW FROM HOTEL; HAMILTON BUNGALOW IN FOREGROUND; BUNGALOW NO. 3 DIRECTLY BEHIND; HINDS & CONNER AND "A" BUNGALOWS IN REAR. VISTA DEL ARROYO HOTEL ON RIGHT - Vista del Arroyo Hotel, 125 South Grand Avenue, Pasadena, Los Angeles County, CA

  3. 33. VIEW LOOKING NORTHNORTHWEST AT THE DENNIS HOTEL (PARTIAL VIEW ...

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

    33. VIEW LOOKING NORTH-NORTHWEST AT THE DENNIS HOTEL (PARTIAL VIEW OF THE BLENHEIM HOTEL) - Marlborough, Blenheim & Dennis Hotels (aerial views), Between Park Place, Michigan Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  4. 1. General view of the Moody Hotel, Tremont Square. The ...

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

    1. General view of the Moody Hotel, Tremont Square. The hotel was built by William Emerson in 1890-92. - Claremont Village Industrial District, Moody Hotel, Tremont Square, Claremont, Sullivan County, NH

  5. 39. VIEW LOOKING NORTHNORTHEAST AT THE MARLBOROUGH HOTEL WITH THE ...

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

    39. VIEW LOOKING NORTH-NORTHEAST AT THE MARLBOROUGH HOTEL WITH THE BLENHEIM HOTEL IN THE BACKGROUND - Marlborough, Blenheim & Dennis Hotels (aerial views), Between Park Place, Michigan Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  6. 88. VIEW LOOKING FROM THE BRIDGE FROM THE MARLBOROUGH HOTEL ...

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

    88. VIEW LOOKING FROM THE BRIDGE FROM THE MARLBOROUGH HOTEL TOWARD THE READING LOUNGE OUTSIDE OF THE MAIN DINING ROOM OF THE BLENHEIM HOTEL - Blenheim Hotel, Ohio Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  7. 43. VIEW LOOKING WEST AT THE MARLBOROUGH HOTEL WITH THE ...

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

    43. VIEW LOOKING WEST AT THE MARLBOROUGH HOTEL WITH THE BLENHEIM, DENNIS,AND SHELBOURNE HOTELS BEYOUND - Marlborough, Blenheim & Dennis Hotels (aerial views), Between Park Place, Michigan Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  8. 4. photocopy of an advertisement (from Penn Alto Hotel archives, ...

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

    4. photocopy of an advertisement (from Penn Alto Hotel archives, Altoona, Pennsylvania) ADVERTISEMENT TO SELL STOCK IN PENN ALTO HOTEL - Penn Alto Hotel, 1120-1130 Thirteenth Avenue, Altoona, Blair County, PA

  9. 3. photocopy of an advertisement (from Penn Alto Hotel archives, ...

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

    3. photocopy of an advertisement (from Penn Alto Hotel archives, Altoona, Pennsylvania) ADVERTISEMENT TO SELL STOCK IN PENN ALTO HOTEL - Penn Alto Hotel, 1120-1130 Thirteenth Avenue, Altoona, Blair County, PA

  10. Promotion of responsible drinking in hotels.

    PubMed

    McLean, S; Wood, L J; Montgomery, I M; Davidson, J; Jones, M E

    1994-01-01

    This study reports on an intervention programme to promote responsible drinking in hotels. The licensees of eight hotels agreed to participate in a trial of measures designed to assist patrons to avoid drink-driving, and seven other hotels were used as controls. The interventions acceptable to licensees comprised commercial-quality promotional material with the theme "0.05 Know Your Limits", and a breath analysis machine and poster on its use. Patrons leaving the hotels on Thursday, Friday and Saturday nights were interviewed and breath-tested. Although the intervention material had been seen by one-third of patrons in the intervention hotels, there was no significant difference between them and control hotel patrons in either median BAC or the proportion who were going to drive with BAC over the legal limit. There was poor compliance by hotels with the intervention procedures, indicating that a major impediment to the implementation and evaluation of programmes to promote responsible drinking is a lack of motivation by many licensees, despite support by some licensees and the Australian Hotels Association.

  11. Fireguard Training for Hotel Employees: Sprinkler Module.

    ERIC Educational Resources Information Center

    Mason, James

    This thesis examines the analysis, design, development, implementation, and evaluation of an instructional development project addressing hotel fireguards. Systematic techniques were applied to produce a session to train the appropriate hotel employees to qualify as fireguards. The portion of training represented in this report is the sprinkler…

  12. Housekeeping ESL. Workplace Literacy Curriculum for Hotels.

    ERIC Educational Resources Information Center

    Van Duzer, Carol; And Others

    This curriculum for hotel employees is based on the analyses of worksite tasks and interactions. Hotel housekeepers were observed on the job, supervisors were consulted, and existing resources were reviewed to determine the language and basic skills needed to effectively and efficiently perform job duties. Twelve curriculum units were developed,…

  13. Hotel Housekeeping Work Influences on Hypertension Management

    PubMed Central

    Sanon, Marie-Anne

    2013-01-01

    Background Characteristics of hotel housekeeping work increase the risk for hypertension development. Little is known about the influences of such work on hypertension management. Methods For this qualitative study, 27 Haitian immigrant hotel housekeepers from Miami-Dade County, FL were interviewed. Interview transcripts were analyzed with the assistance of the Atlas. ti software for code and theme identification. Results Influences of hotel housekeeping work on hypertension management arose both at the individual and system levels. Factors at the individual level included co-worker dynamics and maintenance of transmigrant life. Factors at the system level included supervisory support, workload, work pace, and work hiring practices. No positive influences were reported for workload and hiring practices. Conclusions Workplace interventions may be beneficial for effective hypertension management among hotel housekeepers. These work influences must be considered when determining effective methods for hypertension management among hotel housekeepers. PMID:23775918

  14. 30. VIEW LOOKING NORTH AT DENNIS HOTEL SOUTH ELEVATION. BLENHEIM ...

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

    30. VIEW LOOKING NORTH AT DENNIS HOTEL SOUTH ELEVATION. BLENHEIM HOTEL SOUTH ELEVATION IS PARTIALLY VISIBLE TO THE RIGHT. SHELBOURNE HOTEL IS PARTIALLY VISIBLE TO THE LEFT - Marlborough, Blenheim & Dennis Hotels (aerial views), Between Park Place, Michigan Avenue & Boardwalk, Atlantic City, Atlantic County, NJ

  15. Geography Matters in Online Hotel Reviews

    NASA Astrophysics Data System (ADS)

    Wang, Mingshu; Zhou, Xiaolu

    2016-06-01

    In resonance with the popularity of user-generated contents (UGC) and the volunteered geographic information (VGI), this study crowdsourced 77,098 hotel reviews of 220 hotels provided by U.S. reviewers in the city of San Francisco, 2002 to 2015. In this exploratory analysis, we have revealed that there is spatial dependence of customer satisfaction at different locations (of hotels), which violates the assumption that ordinary least-square (OLS) is the best linear unbiased estimator (BLUE); therefore, spatial model might be required for analysing any antecedents and consequences of such phenomena. These results have implications in marketing and management strategies.

  16. The homeless: help from hotels and restaurants.

    PubMed

    Hales, A; Eyster, J J; Ford, J L

    1993-07-01

    Specific examples and information are given to service providers to address the needs of homeless people. Together nurses and restaurant and hotel managers combined their expertise to assist local agencies in their community kitchens and shelters.

  17. Rosebud Casino and Hotel NPDES Permit

    EPA Pesticide Factsheets

    Under NPDES permit SD-0034584, Rosebud Casino and Hotel, South Dakota, is authorized to discharge from its wastewater treatment facility in Todd County, South Dakota to an unnamed drainageway(s) tributary to Rock Creek.

  18. Spinning reserve from hotel load response

    SciTech Connect

    Kirby, Brendan; Kueck, John; Laughner, Theo; Morris, Keith

    2008-12-15

    Even though preliminary tests were not conducted during times of highest system or hotel loading during the summer, they showed that hotel load can be curtailed by 22 to 37 percent depending on the outdoor temperature and time of day. Full response occurred in 12 to 60 seconds from when the system operator's command to shed load was issued and the load drop was very rapid. (author)

  19. Traveler's encounter with nymphs in a hotel bed.

    PubMed

    Sandlund, Johanna; Banaei, Niaz

    2014-01-01

    This case illustrates skin lesions in a traveler staying in a hotel bed infested with tics. Although infestation of hotels with bedbugs belonging to the Cimex genus is a growing problem worldwide, tick infestation has never been reported before.

  20. Detail, Scandia Hotel, view to southwest showing details of balloon ...

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

    Detail, Scandia Hotel, view to southwest showing details of balloon framing, including full two-story studs notched to carry girts supporting second story floor joists (210mm lens) - Scandia Hotel, 225 First Street, Eureka, Humboldt County, CA

  1. Divisive normalization in channelized Hotelling observer

    NASA Astrophysics Data System (ADS)

    Luo, Tao; Mou, Xuanqin

    2010-02-01

    Channelized Hotelling observers have been evaluated in signal detection in medical images. However, these model observers fall short of overestimate of detection performance compared with human observers. Here, we present a modified channelized Hotelling observer with divisive normalization mechanism. In this model, images first traverse a series of Gabor filters of different orientations, phases and spatial frequencies. Then, the channels outputs pass through a nonlinear process and pool in several channels. Finally, these channels responses are normalized through a divisive operation. Human performances of nodule detection in chest radiography are evaluated by 2AFC experiments. The same detection tasks are performed by the model observers. The results show that the modified channelized Hotelling observer can well predict the human performances.

  2. 40 CFR 30.18 - Hotel and motel fire safety.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 1 2012-07-01 2012-07-01 false Hotel and motel fire safety. 30.18... EDUCATION, HOSPITALS, AND OTHER NON-PROFIT ORGANIZATIONS Pre-Award Requirements § 30.18 Hotel and motel fire safety. The Hotel and Motel Fire Safety Act of 1990 (Public Law 101-391) establishes a number of...

  3. 40 CFR 30.18 - Hotel and motel fire safety.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 1 2014-07-01 2014-07-01 false Hotel and motel fire safety. 30.18... EDUCATION, HOSPITALS, AND OTHER NON-PROFIT ORGANIZATIONS Pre-Award Requirements § 30.18 Hotel and motel fire safety. The Hotel and Motel Fire Safety Act of 1990 (Public Law 101-391) establishes a number of...

  4. 40 CFR 30.18 - Hotel and motel fire safety.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 1 2011-07-01 2011-07-01 false Hotel and motel fire safety. 30.18... EDUCATION, HOSPITALS, AND OTHER NON-PROFIT ORGANIZATIONS Pre-Award Requirements § 30.18 Hotel and motel fire safety. The Hotel and Motel Fire Safety Act of 1990 (Public Law 101-391) establishes a number of...

  5. 40 CFR 30.18 - Hotel and motel fire safety.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 1 2013-07-01 2013-07-01 false Hotel and motel fire safety. 30.18... EDUCATION, HOSPITALS, AND OTHER NON-PROFIT ORGANIZATIONS Pre-Award Requirements § 30.18 Hotel and motel fire safety. The Hotel and Motel Fire Safety Act of 1990 (Public Law 101-391) establishes a number of...

  6. 40 CFR 30.18 - Hotel and motel fire safety.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 1 2010-07-01 2010-07-01 false Hotel and motel fire safety. 30.18... EDUCATION, HOSPITALS, AND OTHER NON-PROFIT ORGANIZATIONS Pre-Award Requirements § 30.18 Hotel and motel fire safety. The Hotel and Motel Fire Safety Act of 1990 (Public Law 101-391) establishes a number of...

  7. Hotel Employees' Japanese Language Experiences: Implications and Suggestions.

    ERIC Educational Resources Information Center

    Makita-Discekici, Yasuko

    1998-01-01

    Analyzes the Japanese language learning experiences of 13 hotel employees in Guam. Results of the study present implications and suggestions for a Japanese language program for the hotel industry. The project began as a result of hotel employees frustrations when they were unable to communicate effectively with their Japanese guests. (Auth/JL)

  8. The Application of Intelligent Building Technologies to Space Hotels

    NASA Astrophysics Data System (ADS)

    Fawkes, S.

    This paper reports that over the last few years Intelligent Building technologies have matured and standardised. It compares the functions of command and control systems in future large space facilities such as space hotels to those commonly found in Intelligent Buildings and looks at how Intelligent Building technologies may be applied to space hotels. Many of the functions required in space hotels are the same as those needed in terrestrial buildings. The adaptation of standardised, low cost, Intelligent Building technologies would reduce capital costs and ease development of future space hotels. Other aspects of Intelligent Buildings may also provide useful models for the development and operation of space hotels.

  9. Women in the Hotel and Catering Industry.

    ERIC Educational Resources Information Center

    Hotel and Catering Training Board, Wembley (England).

    A study of the employment of women in the hotel and catering industry indicated that the industry employs nearly 17 percent of the entire paid female work force in the United Kingdom. Women constitute 75 percent of the industry's work force, and 47 percent of its managers are women. Women's position in the industry is characterized by their…

  10. Smoking in hotels: prevalence, and opinions about restrictions.

    PubMed

    Semmonds, A; Bailey, K; Bentley, S; Chase, V; Fernando, S; Guruge, A; King, M; Tan, O M; Walsh, R

    1995-02-01

    Exposure to high levels of environmental tobacco smoke can occur in hotels. Controversy exists about smoking regulation on licensed premises. This survey of 138 people attending one of three Newcastle hotels during 1993 found that 57 per cent of respondents were nonsmokers. Fifty-eight per cent (95 per cent confidence interval (CI) 50 to 66 per cent) of respondents in these hotels believed their health was being adversely affected by other people's smoke in the hotel. Seventy per cent (CI 62 to 78 per cent), including half the smokers, were in favour of restriction of smoking in the hotels. Most preferred the establishment of smoke-free areas to the introduction of total smoking bans in hotels. The failure of hotels to regulate smoking suggests that a legislative approach is required. The case for legislation would be strengthened by a larger study elsewhere in Australia.

  11. Legionellosis Outbreak Associated With a Hotel Fountain

    PubMed Central

    Smith, Shamika S.; Ritger, Kathy; Samala, Usha; Black, Stephanie R.; Okodua, Margaret; Miller, Loretta; Kozak-Muiznieks, Natalia A.; Hicks, Lauri A.; Steinheimer, Craig; Ewaidah, Saadeh; Presser, Lance; Siston, Alicia M.

    2015-01-01

    Background. In August 2012, the Chicago Department of Public Health (CDPH) was notified of acute respiratory illness, including 1 fatality, among a group of meeting attendees who stayed at a Chicago hotel during July 30–August 3, 2012. Suspecting Legionnaires' disease (LD), CDPH advised the hotel to close their swimming pool, spa, and decorative lobby fountain and began an investigation. Methods. Case finding included notification of individuals potentially exposed during July 16–August 15, 2012. Individuals were interviewed using a standardized questionnaire. An environmental assessment was performed. Results. One hundred fourteen cases were identified: 11 confirmed LD, 29 suspect LD, and 74 Pontiac fever cases. Illness onsets occurred July 21–August 22, 2012. Median age was 48 years (range, 22–82 years), 64% were male, 59% sought medical care (15 hospitalizations), and 3 died. Relative risks for hotel exposures revealed that persons who spent time near the decorative fountain or bar, both located in the lobby were respectively 2.13 (95%, 1.64–2.77) and 1.25 (95% CI, 1.09–1.44) times more likely to become ill than those who did not. Legionella pneumophila serogroup 1 was isolated from samples collected from the fountain, spa, and women's locker room fixtures. Legionella pneumophila serogroup 1 environmental isolates and a clinical isolate had matching sequence-based types. Hotel maintenance records lacked a record of regular cleaning and disinfection of the fountain. Conclusions. Environmental testing identified Legionella in the hotel's potable water system. Epidemiologic and laboratory data indicated the decorative fountain as the source. Poor fountain maintenance likely created favorable conditions for Legionella overgrowth. PMID:26716104

  12. Legionellosis Outbreak Associated With a Hotel Fountain.

    PubMed

    Smith, Shamika S; Ritger, Kathy; Samala, Usha; Black, Stephanie R; Okodua, Margaret; Miller, Loretta; Kozak-Muiznieks, Natalia A; Hicks, Lauri A; Steinheimer, Craig; Ewaidah, Saadeh; Presser, Lance; Siston, Alicia M

    2015-12-01

    Background.  In August 2012, the Chicago Department of Public Health (CDPH) was notified of acute respiratory illness, including 1 fatality, among a group of meeting attendees who stayed at a Chicago hotel during July 30-August 3, 2012. Suspecting Legionnaires' disease (LD), CDPH advised the hotel to close their swimming pool, spa, and decorative lobby fountain and began an investigation. Methods.  Case finding included notification of individuals potentially exposed during July 16-August 15, 2012. Individuals were interviewed using a standardized questionnaire. An environmental assessment was performed. Results.  One hundred fourteen cases were identified: 11 confirmed LD, 29 suspect LD, and 74 Pontiac fever cases. Illness onsets occurred July 21-August 22, 2012. Median age was 48 years (range, 22-82 years), 64% were male, 59% sought medical care (15 hospitalizations), and 3 died. Relative risks for hotel exposures revealed that persons who spent time near the decorative fountain or bar, both located in the lobby were respectively 2.13 (95%, 1.64-2.77) and 1.25 (95% CI, 1.09-1.44) times more likely to become ill than those who did not. Legionella pneumophila serogroup 1 was isolated from samples collected from the fountain, spa, and women's locker room fixtures. Legionella pneumophila serogroup 1 environmental isolates and a clinical isolate had matching sequence-based types. Hotel maintenance records lacked a record of regular cleaning and disinfection of the fountain. Conclusions.  Environmental testing identified Legionella in the hotel's potable water system. Epidemiologic and laboratory data indicated the decorative fountain as the source. Poor fountain maintenance likely created favorable conditions for Legionella overgrowth.

  13. Chronic disease risk factors among hotel workers

    PubMed Central

    Gawde, Nilesh Chandrakant; Kurlikar, Prashika R.

    2016-01-01

    Context: Non-communicable diseases have emerged as a global health issue. Role of occupation in pathogenesis of non-communicable diseases has not been explored much especially in the hospitality industry. Aims: Objectives of this study include finding risk factor prevalence among hotel workers and studying relationship between occupational group and chronic disease risk factors chiefly high body mass index. Settings and Design: A cross-sectional study was conducted among non-managerial employees from classified hotels in India. Materials and Methods: The study participants self-administered pre-designed pilot-tested questionnaires. Statistical analysis used: The risk factor prevalence rates were expressed as percentages. Chi-square test was used for bi-variate analysis. Overweight was chosen as ‘outcome’ variable of interest and binary multi-logistic regression analysis was used to identify determinants. Results: The prevalence rates of tobacco use, alcohol use, inadequate physical activity and inadequate intake of fruits and vegetables were 32%, 49%, 24% and 92% respectively among hotel employees. Tobacco use was significantly common among those in food preparation and service, alcohol use among those in food service and security and leisure time physical activity among front office workers. More than two-fifths (42.7%) were overweight. Among the hotel workers, those employed in food preparation and security had higher odds of 1.650 (CI: 1.025 – 2.655) and 3.245 (CI: 1.296 – 8.129) respectively of being overweight. Conclusions: Prevalence of chronic disease risk factors is high among hotel workers. Risk of overweight is significantly high in food preparation and security departments and workplace interventions are necessary to address these risks PMID:27390474

  14. Design challenges and coordination issues in hotel projects

    NASA Astrophysics Data System (ADS)

    Saunders, Melvin L., IV; Marsh, David

    2002-11-01

    The design of a Five Star hotel facility encompasses a myriad of design dilemmas. On the same note, the design of a One Star or Two Star hotel has many dilemmas of its own. The ability of an acoustical consultant, as an integral part of the design team, to recognize the differences between these types of projects can be the difference between a successful hotel project and miserable failure. Different quality hotels require different levels of design criteria. Proper coordination and timing between trades and installations, such as loudspeakers, ceiling coffers, chandeliers, sprinkler heads, and ductwork, is also very important for the success of the overall project. This paper will discuss techniques and methods to produce successful hotel projects, as well as various noise sources throughout these spaces. It will also highlight a number of tips learned through many hotel design experiences.

  15. Isolation of Legionella pneumophila from hotels of Greece.

    PubMed

    Alexiou, S D; Antoniadis, A; Papapaganagiotou, J; Stefanou, T

    1989-03-01

    Twenty water samples collected from 6 hotels situated in various areas of Greece were examined for the presence of Legionella pneumophila and Legionella-like organisms. Five of the six hotels included in this investigation were associated with cases of legionellosis. Legionella pneumophila serogroups 1 and 8 were isolated from four of six hotels, mainly from the hot water supply system. This is the first isolation and identification of L. pneumophila in Greece.

  16. Occupational exposures and health outcomes among Latina hotel cleaners.

    PubMed

    Hsieh, Yu-Chin Jerrie; Apostolopoulos, Yorghos; Hatzudis, Kiki; Sönmez, Sevil

    2014-01-01

    The poor working conditions of Latina hotel cleaners render them particularly vulnerable to elevated occupational hazards that lead to adverse health outcomes. This article presents a comprehensive review of occupational risks (including physical, chemical, biological, and psychosocial risk factors) and health outcomes (including musculoskeletal disorders, respiratory diseases, dermatological diseases and allergies, and psychological disorders) for Latina hotel cleaners, within their unique sociocultural contexts. Preventive interventions for improving Latina hotel cleaners' work and health conditions are recommended.

  17. Chinese hotel general managers' perspectives on energy-saving practices

    NASA Astrophysics Data System (ADS)

    Zhu, Yidan

    As hotels' concern about sustainability and budget-control is growing steadily, energy-saving issues have become one of the important management concerns hospitality industry face. By executing proper energy-saving practices, previous scholars believed that hotel operation costs can decrease dramatically. Moreover, they believed that conducting energy-saving practices may eventually help the hotel to gain other benefits such as an improved reputation and stronger competitive advantage. The energy-saving issue also has become a critical management problem for the hotel industry in China. Previous research has not investigated energy-saving in China's hotel segment. To achieve a better understanding of the importance of energy-saving, this document attempts to present some insights into China's energy-saving practices in the tourist accommodations sector. Results of the study show the Chinese general managers' attitudes toward energy-saving issues and the differences among the diverse hotel managers who responded to the study. Study results indicate that in China, most of the hotels' energy bills decrease due to the implementation of energy-saving equipments. General managers of hotels in operation for a shorter period of time are typically responsible for making decisions about energy-saving issues; older hotels are used to choosing corporate level concerning to this issue. Larger Chinese hotels generally have official energy-saving usage training sessions for employees, but smaller Chinese hotels sometimes overlook the importance of employee training. The study also found that for the Chinese hospitality industry, energy-saving practices related to electricity are the most efficient and common way to save energy, but older hotels also should pay attention to other ways of saving energy such as water conservation or heating/cooling system.

  18. Renovation And Modernization Of Hotel Buildings - Case Studies In Silesia

    NASA Astrophysics Data System (ADS)

    Bradecki, Tomasz; Uherek-Bradecka, Barbara

    2015-12-01

    The cultural heritage of Silesia has different backgrounds and is often characterized by difficult to assess values. There is doubt as to whether some of the existing buildings should be modernized. Since 2000, an increase in the amount of investments in hotel buildings and conference venues in Poland has been observed. The functions and roles of hotels within a city have also changed. The paper presents examples of original projects and realizations of hotel buildings in Silesia. A discussion was also held regarding the issue of adapting and modernizing hotel buildings.

  19. Hotel & Food Service Industries. Workforce & Workplace Literacy Series.

    ERIC Educational Resources Information Center

    BCL Brief, 1992

    1992-01-01

    This brief gives an overview of the topic of workplace literacy for the hotel and food service industries and lists program contacts. The following organizations operate employee basic skills programs for hotel and food service employees, provide technical assistance, or operate grant programs: Essential Skills Resource Center; Language Training…

  20. VIEW LOOKING WEST TOWARD RESERVOIR HILL. THE SPRR HOTEL WAS ...

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

    VIEW LOOKING WEST TOWARD RESERVOIR HILL. THE SPRR HOTEL WAS LOCATED IN THE STRIPED AREA AT THE BOTTOM OF THE IMAGE, AND THE TRACK RAN BETWEEN THE HILL AND THE HOTEL. - Southern Pacific Railroad Water Settling Reservoir, Yuma Crossing, south bank of Colorado River at foot of Madison Avenue, Yuma, Yuma County, AZ

  1. New Employment Forecasts. Hotel and Catering Industry 1988-1993.

    ERIC Educational Resources Information Center

    Measurement for Management Decision, Ltd., London (England).

    Econometric forecasting models were used to forecast employment levels in the hotel and catering industry in Great Britain through 1993 under several different forecasting scenarios. The growth in employment in the hotel and catering industry over the next 5 years is likely to be broadly based, both across income levels of domestic consumers,…

  2. Management Trainees in the Hotel Industry: What Do Managers Expect?

    ERIC Educational Resources Information Center

    Baum, Tom

    1991-01-01

    Comparison of a survey of 118 United Kingdom hotel managers (53 percent response) with a similar study of 75 U.S. managers found key differences reflecting the impact of cultures on management expectations. Significant similarities support development of an internationally transferable core curriculum for hotel management. (SK)

  3. Changing Occupational Profiles in the Hotel Industry: Case Studies in France, Italy and Spain. Synthesis Report.

    ERIC Educational Resources Information Center

    Gatti, Mario; Grazia Mereu, Maria; Tagliaferro, Claudio

    Changing occupational profiles in the hotel industry in France, Italy, and Spain were examined in case studies that included interviews with hotel managers, human resource managers, and individuals employed in hotel occupations identified as new or entailing new skills. The study focused on the following topics: (1) changes in the hotel industry…

  4. Structure-borne noise at hotels

    NASA Astrophysics Data System (ADS)

    Wilson, George Paul; Jue, Deborah A.

    2002-11-01

    Hotels present a challenging environment for building designers to provide suitable noise and vibration isolation between very incompatible uses. While many are familiar with ways to reduce traditional sources of airborne noise and vibration, structure-borne noise and vibration are often overlooked, often with costly repercussions. Structure-borne noise can be very difficult to pinpoint, and troubleshooting the sources of the vibration can be a tedious process. Therefore, the best approach is to avoid the problem altogether during design, with attention to the building construction, potential vibration sources, building uses and equipment locations. In this paper, the relationship between structure-borne vibration and noise are reviewed, typical vibration sources discussed (e.g., aerobic rooms, laundry rooms, mechanical equipment/building services, and subway rail transit), and key details and design guidance to minimize structure-borne noise provided.

  5. Occupational Programs for the Restaurant/Hotel Business

    ERIC Educational Resources Information Center

    Hoenninger, Ronald W.; Riegel, Carl D.

    1978-01-01

    Describes the development of a Hotel and Restaurant Management Program, designed to provide career training, develop educational opportunities, and provide a forum through which the continuing education needs of the local hospitality industry could be assessed and evaluated. (TP)

  6. PERSPECTIVE VIEW OF THE C. 1925 HOTEL BENTON, LOCATED AT ...

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

    PERSPECTIVE VIEW OF THE C. 1925 HOTEL BENTON, LOCATED AT 408 MONROE AVENUE, VIEW LOOKING SOUTHWEST. - Corvallis Downtown Historic District, Bounded by First & Sixth Streets, Van Buren & Western Avenues, Corvallis, Benton County, OR

  7. 7. FOURTH FLOOR, DETAIL OF HOTEL SOAP LINE TO WEST: ...

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

    7. FOURTH FLOOR, DETAIL OF HOTEL SOAP LINE TO WEST: FERGUSON & HAAS AUTOMATIC WRAPPING MACHINE INSTALLED BY 1929 - Colgate & Company Jersey City Plant, Building No. B-15, 90-96 Greene Street, Jersey City, Hudson County, NJ

  8. 5. FOURTH FLOOR, HOTEL SOAP LINES TO NORTHWEST: PRESS (LEFT ...

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

    5. FOURTH FLOOR, HOTEL SOAP LINES TO NORTHWEST: PRESS (LEFT CENTER), MANUAL CUTTERS (CENTER, RIGHT CENTER) - Colgate & Company Jersey City Plant, Building No. B-15, 90-96 Greene Street, Jersey City, Hudson County, NJ

  9. Move to outpatient settings may boost medical hotels.

    PubMed

    Burns, J

    1992-06-08

    The shift of surgeries to outpatient settings could be healthy for medical hotels, those amenity-equipped facilities originally developed to ease patients out of costly acute-care beds. Because fewer hospitals have a pressing need to use such alternative lodging, some medical hotels are hoping to hitch their fortunes to the outpatient trade, keeping patients overnight after surgeries that don't require hospital admission.

  10. Hellish conditions at single-room occupancy hotels.

    PubMed

    Foley, D

    1998-08-01

    Poor conditions exist in many of the commercial single-room occupancy (SRO) hotels for people who are HIV-positive. Living conditions are unsanitary, brutal, and dangerous, and occupants often experience harassment from the hotel owners and staff. Many of the occupants are drug abusers or are mentally incapacitated, and therefore may not have the ability to secure better housing. The situation in the California Suites, an SRO in Manhattan, is described.

  11. Spinning Reserve from Hotel Air Conditioning Load - SHORT VERSION

    SciTech Connect

    Kueck, John D; Kirby, Brendan J

    2008-01-01

    Even though preliminary tests were not conducted during times of highest system or hotel loading during the summer, they showed that hotel load can be curtailed by 22 to 37 percent depending on the outdoor temperature and time of day. Full response occurred in 12 to 60 seconds from when the system operator's command to shed load was issued and the load drop was very rapid.

  12. Research on the Hotel Image Based on the Detail Service

    NASA Astrophysics Data System (ADS)

    Li, Ban; Shenghua, Zheng; He, Yi

    Detail service management, initially developed as marketing programs to enhance customer loyalty, has now become an important part of customer relation strategy. This paper analyzes the critical factors of detail service and its influence on the hotel image. We establish the theoretical model of influencing factors on hotel image and propose corresponding hypotheses. We use applying statistical method to test and verify the above-mentioned hypotheses. This paper provides a foundation for further study of detail service design and planning issues.

  13. Discrimination against same-sex couples in hotel reservation policies.

    PubMed

    Jones, D A

    1996-01-01

    Discrimination against same-sex couples in hotel reservations policies was investigated. Hotels and bed and breakfast establishments (N = 320) were sent letters from either a same-sex or opposite-sex couple, requesting weekend reservations for a room with one bed. Same-sex couples were granted significantly fewer reservations than opposite-sex couples, suggesting that there was indeed discrimination against same-sex couples.

  14. Hotel in the Bahamas profits from solar hot water system

    SciTech Connect

    Not Available

    1993-01-01

    On Paradise Island, located in the Bahamas, American Energy Technologies Inc. (AET) recently designed and supplied a domestic solar water heating system for the new Comfort Suites Hotel. AET is a Florida manufacturer of solar thermal collectors. The hotel has 150 rooms. Hot water usage entails the laundry facilities and the limited kitchen facilities. Access to hot showers is more of a luxury in some places, but guests at the Comfort Suites Hotel need not be concerned. During the development of the hotel, it was noted that the high heating costs of the propane-fueled hotel boiler were somewhat prohibitive. Propane cost approximately $1.67/gallon, causing the cost of heating water for the hotel to be estimated at over $1,000 per month. To offset the high heating costs, a 49-collector system on a 3200 gallon storage tank was designed into the plans for the new facility. The 49 roof mounted collectors were placed on a direct solar link to the 3200 gallon storage tank. The water is preheated before it gets to the boiler, cutting costs tremendously.

  15. Legionella contamination in hot water of Italian hotels.

    PubMed

    Borella, Paola; Montagna, Maria Teresa; Stampi, Serena; Stancanelli, Giovanna; Romano-Spica, Vincenzo; Triassi, Maria; Marchesi, Isabella; Bargellini, Annalisa; Tatò, Daniela; Napoli, Christian; Zanetti, Franca; Leoni, Erica; Moro, Matteo; Scaltriti, Stefania; Ribera D'Alcalà, Gabriella; Santarpia, Rosalba; Boccia, Stefania

    2005-10-01

    A cross-sectional multicenter survey of Italian hotels was conducted to investigate Legionella spp. contamination of hot water. Chemical parameters (hardness, free chlorine concentration, and trace element concentrations), water systems, and building characteristics were evaluated to study risk factors for colonization. The hot water systems of Italian hotels were strongly colonized by Legionella; 75% of the buildings examined and 60% of the water samples were contaminated, mainly at levels of > or =10(3) CFU liter(-1), and Legionella pneumophila was the most frequently isolated species (87%). L. pneumophila serogroup 1 was isolated from 45.8% of the contaminated sites and from 32.5% of the hotels examined. When a multivariate logistic model was used, only hotel age was associated with contamination, but the risk factors differed depending on the contaminating species and serogroup. Soft water with higher chlorine levels and higher temperatures were associated with L. pneumophila serogroup 1 colonization, whereas the opposite was observed for serogroups 2 to 14. In conclusion, Italian hotels, particularly those located in old buildings, represent a major source of risk for Legionnaires' disease due to the high frequency of Legionella contamination, high germ concentration, and major L. pneumophila serogroup 1 colonization. The possible role of chlorine in favoring the survival of Legionella species is discussed.

  16. Bias in Hotelling observer performance computed from finite data

    NASA Astrophysics Data System (ADS)

    Kupinski, Matthew A.; Clarkson, Eric; Hesterman, Jacob Y.

    2007-03-01

    An observer performing a detection task analyzes an image and produces a single number, a test statistic, for that image. This test statistic represents the observers "confidence" that a signal (e.g., a tumor) is present. The linear observer that maximizes the test-statistic SNR is known as the Hotelling observer. Generally, computation of the Hotelling SNR, or Hotelling trace, requires the inverse of a large covariance matrix. Recent developments have resulted in methods for the estimation and inversion of these large covariance matrices with relatively small numbers of images. The estimation and inversion of these matrices is made possible by a covariance matrix decomposition that splits the full covariance matrix into an average detector-noise component and a background-variability component. Because the average detector-noise component is often diagonal and/or easily estimated, a full-rank, invertible covariance matrix can be produced with few images. We have studied the bias of estimates of the Hotelling trace using this decomposition for high-detector-noise and low-detector noise situations. In extremely low-noise situations, this covariance decomposition may result in a significant bias. We will present a theoretical evaluation of the Hotelling-trace bias, as well as extensive simulation studies.

  17. Ergonomics and accessibility for people with visual impairment in hotels.

    PubMed

    Dos Santos, Larissa Nascimento; de Carvalho, Ricardo José Matos

    2012-01-01

    This article presents a diagnosis of luxury or superior hotels in the city of Natal, located in the state of Rio Grande do Norte, in northeastern Brazil, in what concerns accessibility to the visually impaired. The main objective is to present the guiding principles to design actions and interventions that must be considered in the preparation or revision of technical standards and manuals of good practice in accessibility related to people with visual impairments who are hotel users. The survey showed that the hotels do not meet the normative indications of accessibility, their facilities are in-accessible (have prevented access) or of reduced accessibility and its employees are not prepared to provide adequate hospital services for people with visual impairment. It was concluded that some of the accessibility problems faced by people with visual impairments are also faced by people in general.

  18. Space-Hotel Early Bird - Visions for a Commercial Space Hotel

    NASA Astrophysics Data System (ADS)

    Amekrane, R.; Holze, C.; Apel, U.

    2002-01-01

    rachid.amekrane@astrium-space.com/Fax: +49 421 539-24801, cholze@zarm.uni-bremen.de/Fax: +49 421 218-7473, The International Space Station was planed for research purposes. In 2001 the first private man, Denis Tito,visited the ISS and the second private man, Mark Shuttleworth is following him. The gate towards the commercial utilization of manned space flight has been pushed open. Space pioneers as Wernher von Braun and Sir Arthur C. Clarke had the dream that one day a space station in earth orbit will host tourists. It is evident that the ISS is not designed to host tourists. Therefore the dream of the pioneers is still open. By asking the question "how should a space station should look like to host tourists?", the German Aerospace Society DGLR e.V. organized a contest under the patronage of Mr. Joerg Feustel-Buechl, the Director of Manned Spaceflight and Microgravity, European Space Agency (ESA) in April 2001. Because the definition and design of living space is the content of architecture the approach was to gather new ideas from young architects in cooperation with space experts. This contest was directed at students of architecture and the task set was to design a hotel for the earth orbit and to accommodate 220 guests. The contest got the name "Early Bird - Visions of a Space Hotel". The results and models of the student's work were shown in an exhibition in Hamburg/Germany, which was open to the public from September 19th till October 20th 2001. During the summer term of 2001 seventeen designs were completed. Having specialists, as volunteers, in the field of space in charge meant that it could be ensured that the designs reflected a certain possibility of being able to be realized. Within this interdisciplinary project both parties learned from each other. The 17 different designs were focused on the expectations and needs of a future space tourist. The designs are for sure not feasible today, but the designs are in that sense realistic that they could be

  19. 77 FR 37326 - Safety Zone; Grand Hotel 125th Anniversary Fireworks Celebration, Mackinaw Island, MI

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-06-21

    ... SECURITY Coast Guard 33 CFR Part 165 RIN 1625-AA00 Safety Zone; Grand Hotel 125th Anniversary Fireworks... launched from a point on Lake Huron to commemorate the Grand Hotel's 125th anniversary. The Captain of the Port, Sector Sault Sainte Marie, has determined that the Grand Hotel Celebration Fireworks Display...

  20. Employment Prospects in the Hotel and Catering Trade: A Franco-American Comparison.

    ERIC Educational Resources Information Center

    Meriot, Sylvie-Anne

    2000-01-01

    In both France and the United States, restaurants remain the hotel and catering sector's main employer. In France, 25% of hotel and catering personnel are self-employers versus fewer than 5% in the United States; however, the growth of hotel and restaurant chains in France may eventually limit opportunities for creating an independent activity.…

  1. Evaluation of internal noise methods for Hotelling observers

    NASA Astrophysics Data System (ADS)

    Zhang, Yani; Pham, Binh T.; Eckstein, Miguel P.

    2005-04-01

    Including internal noise in computer model observers to degrade model observer performance to human levels is a common method to allow for quantitatively comparisons of human and model performance. In this paper, we studied two different types of methods for injecting internal noise to Hotelling model observers. The first method adds internal noise to the output of the individual channels: a) Independent non-uniform channel noise, b) Independent uniform channel noise. The second method adds internal noise to the decision variable arising from the combination of channel responses: a) internal noise standard deviation proportional to decision variable's standard deviation due to the external noise, b) internal noise standard deviation proportional to decision variable's variance caused by the external noise. We tested the square window Hotelling observer (HO), channelized Hotelling observer (CHO), and Laguerre-Gauss Hotelling observer (LGHO). The studied task was detection of a filling defect of varying size/shape in one of four simulated arterial segment locations with real x-ray angiography backgrounds. Results show that the internal noise method that leads to the best prediction of human performance differs across the studied models observers. The CHO model best predicts human observer performance with the channel internal noise. The HO and LGHO best predict human observer performance with the decision variable internal noise. These results might help explain why previous studies have found different results on the ability of each Hotelling model to predict human performance. Finally, the present results might guide researchers with the choice of method to include internal noise into their Hotelling models.

  2. Automatic recognition of biological shapes using the Hotelling transform.

    PubMed

    Sanchez-Marin, F J

    2001-03-01

    We present two contour-based techniques, for computerized object recognition that avoid the difficulties due to translations, rotations and scaling. Our techniques do not require any shape representation. The first technique uses the scale-space filtered coordinate functions of contours and their "largest diameters". The second, uses the Hotelling transform of the vector representations of the points of contours. We applied both techniques to recognize human corneal endothelial cells, embedded in a sample of tissue. The results obtained using the Hotelling transform represent a considerable improvement when compared to those previously obtained using the coordinate functions, the curvature function and Fourier descriptors as representations of shape.

  3. Spinning Reserve From Hotel Load Response: Initial Progress

    SciTech Connect

    Kueck, John D; Kirby, Brendan J

    2008-11-01

    This project was motivated by the fundamental match between hotel space conditioning load response capability and power system contingency response needs. As power system costs rise and capacity is strained demand response can provide a significant system reliability benefit at a potentially attractive cost. At ORNL s suggestion, Digital Solutions Inc. adapted its hotel air conditioning control technology to supply power system spinning reserve. This energy saving technology is primarily designed to provide the hotel operator with the ability to control individual room temperature set-points based upon occupancy (25% to 50% energy savings based on an earlier study [Kirby and Ally, 2002]). DSI added instantaneous local load shedding capability in response to power system frequency and centrally dispatched load shedding capability in response to power system operator command. The 162 room Music Road Hotel in Pigeon Forge Tennessee agreed to host the spinning reserve test. The Tennessee Valley Authority supplied real-time metering equipment in the form of an internet connected Dranetz-BMI power quality meter and monitoring expertise to record total hotel load during both normal operations and test results. The Sevier County Electric System installed the metering. Preliminary testing showed that hotel load can be curtailed by 22% to 37% depending on the outdoor temperature and the time of day. These results are prior to implementing control over the common area air conditioning loads. Testing was also not at times of highest system or hotel loading. Full response occurred in 12 to 60 seconds from when the system operator s command to shed load was issued. The load drop was very rapid, essentially as fast as the 2 second metering could detect, with all units responding essentially simultaneously. Load restoration was ramped back in over several minutes. The restoration ramp can be adjusted to the power system needs. Frequency response testing was not completed. Initial

  4. Health status of hotel workers with special reference to high risk practices and STDs.

    PubMed

    Pawar, A T; Kakrani, V A

    2007-01-01

    A cross sectional study was conducted on health status of hotel workers of Pune city. Out of estimated 1000 hotel workers 516 were selected by stratified random sampling technique. The study revealed that 71.5% hotel workers were suffering from one or other type of morbid condition. Anemia was the commonest morbidity with prevalence of 40.3%. 187 (36.2%) of hotel workers had extramarital sexual relations. A total of 77 (14.9%) hotel workers were having STDs at the time of study.

  5. Understanding Work-Family Spillover in Hotel Managers

    PubMed Central

    Lawson, Katie M.; Davis, Kelly D.; Crouter, Ann C.; O’Neill, John W.

    2013-01-01

    The present study examined the experience of work-family spillover among 586 hotel managers (HMs) working in 50 full-service hotels throughout the U.S. Work-family spillover occurs when behaviors, moods, stresses, and emotions from work spill over into family. We first investigated which hotel managers were more likely to experience spillover and stressful work conditions based on their life circumstances (gender, parental status, age, decision-making latitude at work). Second, we investigated which work conditions (hours worked per week, organizational time expectations, emotional labor, and permeable boundaries) predicted more work-family spillover. Women, employees without children at home, and younger adults experienced the highest levels of negative work-family spillover. Work conditions, particularly organizational time expectations, put HMs at risk for experiencing more negative and less positive work-family spillover. The results provide evidence that modifying certain work conditions in the hotel industry may be helpful in improving the quality of HMs’ jobs and retention. PMID:23888092

  6. Residents' Coping Strategies in an Extended-Stay Hotel Home

    ERIC Educational Resources Information Center

    Lewinson, Terri

    2010-01-01

    Some families live in extended-stay hotels as a solution after housing displacement. This temporary accommodation provides a furnished home environment with resources such as a kitchenette, bed, heating/air conditioning, and room services with one payment that can be made weekly or monthly without a credit check or rent deposit. Despite these…

  7. Food and Beverage Industry ESL Workplace Literacy Curriculum for Hotels.

    ERIC Educational Resources Information Center

    Van Duzer, Carol; And Others

    The Workplace Literacy Curriculum for Food and Beverage was developed for English-as-a-Second-Language classes for workers in participating hotels in Arlington County, Virginia, through a national workplace literacy grant with the cooperation of the Arlington County Chamber of Commerce. It is based on an analysis of tasks and interactions at the…

  8. OpinionSeer: interactive visualization of hotel customer feedback.

    PubMed

    Wu, Yingcai; Wei, Furu; Liu, Shixia; Au, Norman; Cui, Weiwei; Zhou, Hong; Qu, Huamin

    2010-01-01

    The rapid development of Web technology has resulted in an increasing number of hotel customers sharing their opinions on the hotel services. Effective visual analysis of online customer opinions is needed, as it has a significant impact on building a successful business. In this paper, we present OpinionSeer, an interactive visualization system that could visually analyze a large collection of online hotel customer reviews. The system is built on a new visualization-centric opinion mining technique that considers uncertainty for faithfully modeling and analyzing customer opinions. A new visual representation is developed to convey customer opinions by augmenting well-established scatterplots and radial visualization. To provide multiple-level exploration, we introduce subjective logic to handle and organize subjective opinions with degrees of uncertainty. Several case studies illustrate the effectiveness and usefulness of OpinionSeer on analyzing relationships among multiple data dimensions and comparing opinions of different groups. Aside from data on hotel customer feedback, OpinionSeer could also be applied to visually analyze customer opinions on other products or services.

  9. Competency Needs in Irish Hotels: Employer and Graduate Perspectives

    ERIC Educational Resources Information Center

    Nolan, Ciara; Conway, Edel; Farrell, Tara; Monks, Kathy

    2010-01-01

    Purpose: The purpose of this study is to investigate hotel industry employers' expectations of, and satisfaction with, graduate competencies in comparison with graduate perceptions of what is required for their roles and their satisfaction with how well their education experience prepared them. Design/methodology/approach: The research involved a…

  10. The Crystal Hotel: A Microfluidic Approach to Biomimetic Crystallization.

    PubMed

    Gong, Xiuqing; Wang, Yun-Wei; Ihli, Johannes; Kim, Yi-Yeoun; Li, Shunbo; Walshaw, Richard; Chen, Li; Meldrum, Fiona C

    2015-12-02

    A "crystal hotel" microfluidic device that allows crystal growth in confined volumes to be studied in situ is used to produce large calcite single crystals with predefined crystallographic orientation, microstructure, and shape by control of the detailed physical environment, flow, and surface chemistry. This general approach can be extended to form technologically important, nanopatterned single crystals.

  11. Solar-Cooled Hotel in the Virgin Islands

    NASA Technical Reports Server (NTRS)

    Harber, H.

    1982-01-01

    Performance of solar cooling system is described in 21-page report. System provides cooling for public areas including ball rooms, restaurant, lounge, lobby and shops. Chilled water from solar-cooling system is also used to cool hot water from hotel's desalinization plant.

  12. Understanding Work-Family Spillover in Hotel Managers.

    PubMed

    Lawson, Katie M; Davis, Kelly D; Crouter, Ann C; O'Neill, John W

    2013-06-01

    The present study examined the experience of work-family spillover among 586 hotel managers (HMs) working in 50 full-service hotels throughout the U.S. Work-family spillover occurs when behaviors, moods, stresses, and emotions from work spill over into family. We first investigated which hotel managers were more likely to experience spillover and stressful work conditions based on their life circumstances (gender, parental status, age, decision-making latitude at work). Second, we investigated which work conditions (hours worked per week, organizational time expectations, emotional labor, and permeable boundaries) predicted more work-family spillover. Women, employees without children at home, and younger adults experienced the highest levels of negative work-family spillover. Work conditions, particularly organizational time expectations, put HMs at risk for experiencing more negative and less positive work-family spillover. The results provide evidence that modifying certain work conditions in the hotel industry may be helpful in improving the quality of HMs' jobs and retention.

  13. 13. DETAIL OF REMOVED PLODDER (LOWER HALF) FROM HOTEL SOAP ...

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

    13. DETAIL OF REMOVED PLODDER (LOWER HALF) FROM HOTEL SOAP LINE No. 6 STORED IN G BLOCK (HAER No. NJ-71-NN) - Colgate & Company Jersey City Plant, Building No. B-14, 54-58 Grand Street, Jersey City, Hudson County, NJ

  14. 6. FOURTH FLOOR, DETAIL OF HOTEL SOAP LINE TO NORTH: ...

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

    6. FOURTH FLOOR, DETAIL OF HOTEL SOAP LINE TO NORTH: AMERICAN CAR & FOUNDRY COMPANY MANUAL SOAP CUTTER INSTALLED 1932 (FOREGROUND); CONVEYORS; AND R.A. JONES & COMPANY HORIZONTAL PRESS INSTALLED 1931 (BACKGROUND) - Colgate & Company Jersey City Plant, Building No. B-15, 90-96 Greene Street, Jersey City, Hudson County, NJ

  15. 12. DETAIL OF REMOVED PLODDER (UPPER HALF) FROM HOTEL SOAP ...

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

    12. DETAIL OF REMOVED PLODDER (UPPER HALF) FROM HOTEL SOAP LINE No. 6 STORED IN G BLOCK (HAER No. NJ-71-NN) - Colgate & Company Jersey City Plant, Building No. B-14, 54-58 Grand Street, Jersey City, Hudson County, NJ

  16. Women's Path to Management in the Hotel and Catering Industry.

    ERIC Educational Resources Information Center

    Hotel and Catering Training Board, Wembley (England).

    A study examined the employment patterns of women working in the United Kingdom's hotel and catering industry and the opportunities for vocational education that would lead to careers in management. Sixty-four women from different sectors of the industry were interviewed (including women in senior and middle management and some still looking to be…

  17. Paperwork Plus: Literacy Materials for the Service Industry. Hotel Edition.

    ERIC Educational Resources Information Center

    Bond, Judith; McGill, Teresa

    The instructional materials are intended for use in teaching vocational English and English literacy to limited-English-speaking personnel in the hotel industry. They are designed for learners at three instructional levels, and address job-specific literacy tasks. An introductory section describes the materials and offers suggestions for…

  18. ESL for Hotel/Hospitality Industry. Level: Beginner.

    ERIC Educational Resources Information Center

    Western Suffolk County Board of Cooperative Educational Services, Northport, NY.

    This document contains eight lesson plans for a beginning course in work-related English for non-English or limited-English speaking entry-level employees in the hotel and hospitality industry. Course objectives include the following: helping participants understand and use job-specific vocabulary; receive and understand job-related instructions;…

  19. Evaluation of internal noise methods for Hotelling observer models

    SciTech Connect

    Zhang Yani; Pham, Binh T.; Eckstein, Miguel P.

    2007-08-15

    The inclusion of internal noise in model observers is a common method to allow for quantitative comparisons between human and model observer performance in visual detection tasks. In this article, we studied two different strategies for inserting internal noise into Hotelling model observers. In the first strategy, internal noise was added to the output of individual channels: (a) Independent nonuniform channel noise, (b) independent uniform channel noise. In the second strategy, internal noise was added to the decision variable arising from the combination of channel responses. The standard deviation of the zero mean internal noise was either constant or proportional to: (a) the decision variable's standard deviation due to the external noise, (b) the decision variable's variance caused by the external noise, (c) the decision variable magnitude on a trial to trial basis. We tested three model observers: square window Hotelling observer (HO), channelized Hotelling observer (CHO), and Laguerre-Gauss Hotelling observer (LGHO) using a four alternative forced choice (4AFC) signal known exactly but variable task with a simulated signal embedded in real x-ray coronary angiogram backgrounds. The results showed that the internal noise method that led to the best prediction of human performance differed across the studied model observers. The CHO model best predicted human observer performance with the channel internal noise. The HO and LGHO best predicted human observer performance with the decision variable internal noise. The present results might guide researchers with the choice of methods to include internal noise into Hotelling model observers when evaluating and optimizing medical image quality.

  20. How Clean Are Hotel Rooms? Part II: Examining the Concept of Cleanliness Standards.

    PubMed

    Almanza, Barbara A; Kirsch, Katie; Kline, Sheryl Fried; Sirsat, Sujata; Stroia, Olivia; Choi, Jin Kyung; Neal, Jay

    2015-01-01

    Hotel room cleanliness is based on observation and not on microbial assessment even though recent reports suggest that infections may be acquired while staying in hotel rooms. Exploratory research in the first part of the authors' study was conducted to determine if contamination of hotel rooms occurs and whether visual assessments are accurate indicators of hotel room cleanliness. Data suggested the presence of microbial contamination that was not reflective of visual assessments. Unfortunately, no standards exist for interpreting microbiological data and other indicators of cleanliness in hotel rooms. The purpose of the second half of the authors' study was to examine cleanliness standards in other industries to see if they might suggest standards in hotels. Results of the authors' study indicate that standards from other related industries do not provide analogous criteria, but do provide suggestions for further research.

  1. Evaluation of the channelized Hotelling observer for signal detection in 2D tomographic imaging

    NASA Astrophysics Data System (ADS)

    LaRoque, Samuel J.; Sidky, Emil Y.; Edwards, Darrin C.; Pan, Xiaochuan

    2007-03-01

    Signal detection by the channelized Hotelling (ch-Hotelling) observer is studied for tomographic application by employing a small, tractable 2D model of a computed tomography (CT) system. The primary goal of this manuscript is to develop a practical method for evaluating the ch-Hotelling observer that can generalize to larger 3D cone-beam CT systems. The use of the ch-Hotelling observer for evaluating tomographic image reconstruction algorithms is also demonstrated. For a realistic model for CT, the ch-Hotelling observer can be a good approximation to the ideal observer. The ch-Hotelling observer is applied to both the projection data and the reconstructed images. The difference in signal-to-noise ratio for signal detection in both of these domains provides a metric for evaluating the image reconstruction algorithm.

  2. Perspective view of the Drexel (or Vale) Hotel (Building L), ...

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

    Perspective view of the Drexel (or Vale) Hotel (Building L), located at 123 Main Street South, view looking southwest. This building is a National Register listed property - Vale Commercial Historic District, A Street between Holland & Longfellow Streets, north side of B Street between Holland & Main Streets, Main Street South from A Street through B Street, & Stone House at 283 Main Street South, Vale, Malheur County, OR

  3. Single-room occupancy hotels: possible solutions and alternatives.

    PubMed

    Foley, D

    1998-09-01

    New York City's Division of AIDS Services and Income Support (DASIS) places clients in economical, commercial residences in one of 33 hotels in the New York City area, termed single-room occupancy (SRO) hotels. There have been many problems with these hotels in terms of safety and health. One problem is how to enforce housing laws when city agencies have had drastic personnel cutbacks, and landlords are not held accountable for repairs and building conditions. Without a strategic plan to supplement SROs with necessary services, and a way to deal with homeless people with AIDS, it will be difficult to redeem the condition of SROs and lessen dependency on them as a long-term solution. The West Side SRO Law Project offers tips on how tenants in SROs can safeguard their rights and document their cases if they feel that their rights have been violated. Included is a resource list for legal help and emergency numbers for the Department of Buildings in New York City and the surrounding boroughs.

  4. Work Stress and Well-being in the Hotel Industry

    PubMed Central

    O'Neill, John W.; Davis, Kelly

    2013-01-01

    Employee stress is a significant issue in the hospitality industry, and it is costly for employers and employees alike. Although addressing and reducing stress is both a noble goal and is capable of resulting in expense reductions for employers, the nature and quantity of hospitality employee stress is not fully understood. The first aim of this study was to identify common work stressors in a sample of 164 managerial and hourly workers employed at 65 different hotels who were each interviewed for eight consecutive days. The two most common stressors were interpersonal tensions at work and overloads (e.g., technology not functioning). The second aim was to determine whether there were differences in the types and frequency of work stressors by job type (i.e., managers v. non-managers), gender, and marital status. Hotel managers reported significantly more stressors than hourly employees. There were no significant differences by gender or marital status. The third aim was to investigate whether the various stressors were linked to hotel employee health and work outcomes. More employee and coworker stressors were linked to more negative physical health symptoms. Also, interpersonal tensions at work were linked to lower job satisfaction and greater turnover intentions. PMID:23794780

  5. Work Stress and Well-being in the Hotel Industry.

    PubMed

    O'Neill, John W; Davis, Kelly

    2011-06-01

    Employee stress is a significant issue in the hospitality industry, and it is costly for employers and employees alike. Although addressing and reducing stress is both a noble goal and is capable of resulting in expense reductions for employers, the nature and quantity of hospitality employee stress is not fully understood. The first aim of this study was to identify common work stressors in a sample of 164 managerial and hourly workers employed at 65 different hotels who were each interviewed for eight consecutive days. The two most common stressors were interpersonal tensions at work and overloads (e.g., technology not functioning). The second aim was to determine whether there were differences in the types and frequency of work stressors by job type (i.e., managers v. non-managers), gender, and marital status. Hotel managers reported significantly more stressors than hourly employees. There were no significant differences by gender or marital status. The third aim was to investigate whether the various stressors were linked to hotel employee health and work outcomes. More employee and coworker stressors were linked to more negative physical health symptoms. Also, interpersonal tensions at work were linked to lower job satisfaction and greater turnover intentions.

  6. The Hotel Payload, plans for the period 2003-2006

    NASA Astrophysics Data System (ADS)

    Hansen, Gudmund; Mikalsen, Per-Arne

    2003-08-01

    The cost and complexity of scientific experiments, carried by traditional sounding rocket payloads, are increasing. At the same time the scientific environment faces declining funding for this basic research. In order to meet the invitation from the science community, Andøya Rocket Range runs a programme for developing a sounding rocket payload, in order to achieve an inexpensive and cost-effective tool for atmosphere research and educational training. The Hotel Payload is a new technological payload concept in the sounding rocket family. By means of standardized mechanical structures and electronics, flexibility in data collection and transmission, roomy vehicles are affordable to most of the scientific research environments as well as for educational training. A complete vehicle - ready for installation of scientific experiments - is offered to the scientists to a fixed price. The fixed price service also includes launch services. This paper describes the Hotel Payload concept and its technology. In addition the three year plan for the development project is discussed. The opportunity of using the Hotel Payload as a platform for a collaborative triangle between research, education and industry is also discussed.

  7. Use of hygiene protocols to control the spread of viruses in a hotel.

    PubMed

    Sifuentes, Laura Y; Koenig, David W; Phillips, Ronnie L; Reynolds, Kelly A; Gerba, Charles P

    2014-09-01

    The goals of this study were to observe the spread of viruses in a hotel setting and to assess the effectiveness of a hygiene intervention in reducing their spread. Selected fomites in one hotel room were inoculated with bacteriophage ϕx-174, and fomites in a conference center within the same hotel were inoculated using bacteriophage MS2. Cleaning of the contaminated room resulted in the spread of viruses to other rooms by the housekeeping staff. Furthermore, viruses were transferred by hotel guests to the conference center and a communal kitchen area. Additionally, conference attendees transferred viruses from the conference center to their hotel rooms and a communal kitchen area. This study demonstrated how viruses can be spread throughout a hotel setting by both housekeepers and guests. A hygiene intervention, which included providing hand hygiene products and facial tissues to the guests and disinfecting solutions with disposable wipes to the housekeeping staff, was successful in reducing the spread of viruses between the hotel guest rooms and conference center. The hygiene intervention resulted in significantly reduced transfer of the ϕx-174 between the contaminated hotel room and other hotel rooms, communal areas, and the conference center (p = 0.02).

  8. Impact of the Great East Japan Earthquake on Hotel Industry in Pacific Tohoku Prefectures ---From Spatio-Temporal Dependence of Hotel Availability---

    NASA Astrophysics Data System (ADS)

    Sato, A.

    This paper investigates the impact of the Great Japan Earthquake(and subsequent tsunami turmoil) on socio-economic activities by using data on hotel opportunities collected from an electronic hotel booking service. A method to estimate both primary and secondary regional effects of a natural disaster on human behavior is proposed. It is confirmed that temporal variation in the regional share of available hotels before and after a natural disaster may be an indicator to measure the socio-economic impact at each district.

  9. Hotel and Restaurant Management; A Bibliography of Books and Audio-Visual Materials.

    ERIC Educational Resources Information Center

    Malkames, James P.; And Others

    This bibliography represents a collection of 1,300 book volumes and audiovisual materials collected by the Luzerne County Community College Library in support of the college's Hotel and Restaurant Management curriculum. It covers such diverse topics as advertising, business practices, decoration, nutrition, hotel law, insurance landscaping, health…

  10. Hospitality Service: Hotel and Restaurant Management and Culinary Arts Curriculum Guide.

    ERIC Educational Resources Information Center

    Joliet Junior Coll., IL.

    This publication contains competency-based materials for hotel/restaurant management and culinary arts. The materials are designed for students to learn from a work station concept by rotating through a variety of real work settings in a hotel/restaurant environment. In addition, the materials indicate whether or not the students have developed…

  11. REEP/Hotel Workplace Literacy Project. Evaluation Report. 1988-1990 Grant Period.

    ERIC Educational Resources Information Center

    Peterson, Morris

    The Arlington Education and Employment Program (REEP)/Hotel Workplace Literacy Project served 230 functionally illiterate adults working in hotels and a real estate maintenance firm in Virginia. Job-related English and math, citizenship preparation, and work awareness instruction was provided. An evaluation found that: (1) the project effectively…

  12. Human Resource Development in the Irish Hotel Industry: The Case of the Small Firm.

    ERIC Educational Resources Information Center

    Nolan, Clara

    2002-01-01

    A profile of small businesses in the Irish hotel industry shows that all claim to believe in human resource development but few practice it. Small hotels favor informal, specific job training focused on solution of immediate problems rather than long-term development. (Contains 119 references.) (SK)

  13. The impact of virtual reality functions of a hotel website on travel anxiety.

    PubMed

    Lee, Ook; Oh, Ji-Eun

    2007-08-01

    This study deals with the impact of virtual reality (VR) features that are embedded in a hotel website on travelers' anxiety. Having more information is thought to be a factor in relieving anxiety in travel. A hotel website can be a good place for gathering information about the accommodation. In this study, we posit that a hotel website with VR functions should lead to a reduction in travelers' anxiety about travel. We built a website of a hotel and used VR functions to show the exterior, the lobby, a guest room, and a restaurant through an interactive and spatial shot of the hotel images. The experiment was conducted with a premise that the subjects were about to embark on a journey to an unknown place and to stay at an unknown hotel whose website contained VR functions. The subjects were asked to play with VR functions of the hotel website and then to complete a survey with questions regarding the degree of anxiety on the travel and psychological relief that might have been perceived by the subjects. The result confirms our hypothesis that there is a statistically significant relationship between the degree of travel anxiety and psychological relief caused by the use of VR functions of a hotel website.

  14. What Makes Hotel Expatriates Remain in Their Overseas Assignments: A Grounded Theory Study

    ERIC Educational Resources Information Center

    Ho, Zoe Ju-Yu

    2012-01-01

    In this study the researcher uses a qualitative research design to discover what makes hotel expatriates remain in their overseas assignments. In-depth interviews, participant observations, and personal documents are used as data collection methods. Four hotel expatriates are recruited as participants of the study. The collected interview…

  15. Does Embedding Social Media Channels in Hotel Websites Influence Travelers' Satisfaction and Purchase Intentions?

    ERIC Educational Resources Information Center

    Aluri, Ajay Kumar

    2012-01-01

    In the Internet world today, social media channels have emerged as a top share of Internet usage, and more travelers have started using them to make their hotel plans and purchases. Because of the recommendations of researchers and practitioners, hotel organizations have already embraced social media and have embedded their links on their host…

  16. CAREER TRAINING IN HOTEL AND RESTAURANT OPERATION...AT CITY COLLEGE OF SAN FRANCISCO.

    ERIC Educational Resources Information Center

    BATMALE, LOUIS F.; MULLANY, GEORGE G.

    THE HOTEL AND RESTAURANT PROGRAM, ONE OF 35 SEMIPROFESSIONAL TRAINING PROGRAMS AT CITY COLLEGE OF SAN FRANCISCO, COMBINES GENERAL EDUCATION, RELATED BUSINESS INSTRUCTION, HOTEL AND RESTAURANT CLASSES, FOOD PREPARATION AND SERVICE TRAINING, AND WORK EXPERIENCE. THIS DESCRIPTION OF THE PROGRAM INCLUDES (1) PURPOSES AND OBJECTIVES, (2) CURRICULUM,…

  17. A Trip to the Statler Hilton Hotel. The Special Education Curriculum Series.

    ERIC Educational Resources Information Center

    Kendall, Muriel

    A program designed for high school level work-study classes for students of limited mental ability presents specific curriculum methods and materials to teach information regarding positions available in the hotel industry. A field trip tour of the Boston Statler Hilton Hotel if the focal activity of the unit, and is accompanied by a history of…

  18. The Marketing Effectiveness of Hotel Facebook Pages: From Perspectives of Customers and Messages

    ERIC Educational Resources Information Center

    Leung, Xi Yu

    2012-01-01

    In the hotel industry, social media marketing has become a new trend hoteliers are chasing and an increasing number of hotels are using social media to promote their business. However, the marketing effectiveness of social media is still a big challenge in both academic and business world. Since social media marketing is totally different from…

  19. Parameters for an Effective Entrepreneurial, Regional, Hotel/Restaurant Management Training Program in Manitoba, Canada.

    ERIC Educational Resources Information Center

    Rossing, Rainer C.

    Owners or managers of 34 small and medium-sized hotels and restaurants in the Assiniboine Community College area were interviewed to acquire information for an entrepreneurial, regional hotel and restaurant (H/R) management training program in Manitoba. A literature review revealed the following: employability, vocational technical, and business…

  20. Optimized MBR for greywater reuse systems in hotel facilities.

    PubMed

    Atanasova, Natasa; Dalmau, Montserrat; Comas, Joaquim; Poch, Manel; Rodriguez-Roda, Ignasi; Buttiglieri, Gianluigi

    2017-05-15

    Greywater is an important alternative water source, particularly in semi-arid, touristic areas, where the biggest water demand is usually in the dry period. By using this source wisely, tourist facilities can substantially reduce the pressure to scarce water resources. In densely urbanized touristic areas, where space has high value, compact solutions such as MBR based greywater reuse systems appear very appropriate. This research focuses on technical and economical evaluation of such solution by implementing a pilot MBR to a hotel with separated grey water. The pilot was operated for 6 months, with thorough characterisation of the GW performed, its operation was monitored and its energy consumption was optimized by applying a control system for the air scour. Based on the pilot operation a design and economic model was set to estimate the feasibility (CAPEX, OPEX, payback period of investment) of appropriate scales of MBR based GW systems, including separation of GW, MBR technology, clean water storage and disinfection. The model takes into account water and energy prices in Spain and a planning period of 20 years. The results demonstrated an excellent performance in terms of effluent quality, while the energy demand for air-scour was reduced by up to 35.2%, compared to the manufacturer recommendations. Economical evaluation of the entire MBR based GW reuse system shows its feasibility for sizes already at 5 m(3)/day (60 PE). The payback period of the investment for hotels like the demonstration hotel, treating 30 m(3)/day is 3 years.

  1. 24 CFR 203.16 - Certificate and contract regarding use of dwelling for transient or hotel purposes.

    Code of Federal Regulations, 2011 CFR

    2011-04-01

    ... use of dwelling for transient or hotel purposes. 203.16 Section 203.16 Housing and Urban Development... use of dwelling for transient or hotel purposes. Every application filed with respect to insurance of... housing or any part thereof covered by the mortgage for transient or hotel purposes, together with...

  2. 24 CFR 203.16 - Certificate and contract regarding use of dwelling for transient or hotel purposes.

    Code of Federal Regulations, 2012 CFR

    2012-04-01

    ... use of dwelling for transient or hotel purposes. 203.16 Section 203.16 Housing and Urban Development... use of dwelling for transient or hotel purposes. Every application filed with respect to insurance of... housing or any part thereof covered by the mortgage for transient or hotel purposes, together with...

  3. 24 CFR 203.16 - Certificate and contract regarding use of dwelling for transient or hotel purposes.

    Code of Federal Regulations, 2014 CFR

    2014-04-01

    ... use of dwelling for transient or hotel purposes. 203.16 Section 203.16 Housing and Urban Development... use of dwelling for transient or hotel purposes. Every application filed with respect to insurance of... housing or any part thereof covered by the mortgage for transient or hotel purposes, together with...

  4. 24 CFR 203.16 - Certificate and contract regarding use of dwelling for transient or hotel purposes.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... use of dwelling for transient or hotel purposes. 203.16 Section 203.16 Housing and Urban Development... use of dwelling for transient or hotel purposes. Every application filed with respect to insurance of... housing or any part thereof covered by the mortgage for transient or hotel purposes, together with...

  5. 24 CFR 203.16 - Certificate and contract regarding use of dwelling for transient or hotel purposes.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... use of dwelling for transient or hotel purposes. 203.16 Section 203.16 Housing and Urban Development... use of dwelling for transient or hotel purposes. Every application filed with respect to insurance of... housing or any part thereof covered by the mortgage for transient or hotel purposes, together with...

  6. Primary group interaction of residents in a retirement hotel.

    PubMed

    Hampe, G D; Blevins, A L

    1975-01-01

    The interaction patterns of sixty-three residents age 55 and over living in a retirement hotel for three types of primary groups-kin, friends, and neighbors-were studied. Almost all residents voiced high housing satisfaction and were involved to various degrees in their primary group network. The relative with whom visited the most, usually the adult child, influences the primary group interaction the most, but at the same time may contribute to feelings of uselessness on the part of the retired residents of the apartment complex.

  7. Solar cooling system performance, Frenchman's Reef Hotel, Virgin Islands

    NASA Technical Reports Server (NTRS)

    Harber, H.

    1981-01-01

    The operational and thermal performance of a variety of solar systems are described. The Solar Cooling System was installed in a hotel at St. Thomas, U. S. Virgin Islands. The system consists of the evacuated glass tube collectors, two 2500 gallon tanks, pumps, computerized controller, a large solar optimized industrial sized lithium bromide absorption chiller, and associated plumbing. Solar heated water is pumped through the system to the designed public areas such as lobby, lounges, restaurant and hallways. Auxiliary heat is provided by steam and a heat exchanger to supplement the solar heat.

  8. Solar cooling system performance, Frenchman's Reef Hotel, Virgin Islands

    NASA Astrophysics Data System (ADS)

    Harber, H.

    1981-09-01

    The operational and thermal performance of a variety of solar systems are described. The Solar Cooling System was installed in a hotel at St. Thomas, U. S. Virgin Islands. The system consists of the evacuated glass tube collectors, two 2500 gallon tanks, pumps, computerized controller, a large solar optimized industrial sized lithium bromide absorption chiller, and associated plumbing. Solar heated water is pumped through the system to the designed public areas such as lobby, lounges, restaurant and hallways. Auxiliary heat is provided by steam and a heat exchanger to supplement the solar heat.

  9. Prevalence of Legionella spp. in water systems of hospitals and hotels in South Western Greece.

    PubMed

    Fragou, K; Kokkinos, P; Gogos, C; Alamanos, Y; Vantarakis, A

    2012-01-01

    The aim of the present study was to determine the prevalence of Legionella spp. in water systems of hospitals and hotels located in South Western Greece, to study the molecular epidemiology of the isolated strains and their possible association with bacterial contamination (total count and Pseudomonas aeruginosa), the water pH, and temperature. A prevalence survey for Legionella spp. by culturing techniques in water distribution systems of eight hospitals and nine hotels occurred in South Western Greece. Water sampling and microbiological analysis were carried out following the ISO methods. Legionella pneumophila was detected in 33% and 36% of the distribution systems of hospitals and hotels, respectively. Our survey results suggest a frequent prevalence of elevated concentrations of Legionella spp. in water systems of hospitals and hotels. Our investigation has confirmed the need to regularly monitor the microbiological condition of water systems in hospitals and hotels.

  10. Creating Innovative Solutions for Future Hotel Rooms with Intelligent Multimedia and Pervasive Computing

    NASA Astrophysics Data System (ADS)

    Sharda, Nalin K.

    Pervasive computing and intelligent multimedia technologies are becoming increasingly important to the modern way of living. However, many of their potential applications have not been fully realized yet. This chapter explores how innovative applications can be developed to meet the needs of the next generation hotels. Futuristic hotel rooms aim to be more than “home-away-from-home,” and as a consequence, offer tremendous opportunities for developing innovative applications of pervasive computing and intelligent multimedia. Next generation hotels will make increased use of technology products to attract new customers. High end TV screens, changeable room ambiance, biometric guest recognition, and electronic check-in facilities are some of the features already being implemented by some hotels. Entirely futuristic hotels in the sea, the stratosphere or the outer space, are also being proposed. All of these provide many novel opportunities for developing innovative solutions using intelligent multimedia and ubiquitous computing.

  11. Indoor radon levels in selected hot spring hotels in Guangdong, China.

    PubMed

    Song, Gang; Zhang, Boyou; Wang, Xinming; Gong, Jingping; Chan, Daniel; Bernett, John; Lee, S C

    2005-03-01

    Guangdong is one of the provinces that have most hot springs in China, and many hotels have been set up near hot springs, with spring water introduced into the bath inside each hotel room for hot spring bathing to attract tourists. In the present study, we measured radon in indoor and outdoor air, as well as in hot spring waters, in four hot spring hotels in Guangdong by using NR-667A (III) continuous radon detector. Radon concentrations ranged 53.4-292.5 Bq L(-1) in the hot spring water and 17.2-190.9 Bq m(-3) in outdoor air. Soil gas intrusion, indoor hot spring water use and inefficient ventilation all contributed to the elevated indoor radon levels in the hotel rooms. From the variation of radon levels in closed unoccupied hotel rooms, soil gas intrusion was found to be a very important source of indoor radon in hotel rooms with floors in contact with soils. When there was spring water bathing in the bathes, average radon levels were 10.9-813% higher in the hotel rooms and 13.8-489% higher in bathes compared to their corresponding average levels when there was no spring water use. Spring water use in the hotel rooms had radon transfer coefficients from 1.6x10(-4) to 5.0x10(-3). Radon in some hotel rooms maintained in concentrations much higher than guideline levels might thus have potential health risks to the hotel workers, and technical and management measures should be taken to lower their exposure of radon through inhalation.

  12. What do hotels and hospitals have in common? How we can learn from the hotel industry to take better care of patients

    PubMed Central

    Zygourakis, Corinna C.; Rolston, John D.; Treadway, James; Chang, Susan; Kliot, Michel

    2014-01-01

    Despite widely divergent public perceptions and goals, hotels and hospitals share many core characteristics. Both serve demanding and increasingly well-informed clienteles, both employ a large hierarchy of workers with varying levels of responsibility, and both have payments that are increasingly tied to customer/patient evaluations. In the hotel industry, decades of management experience and market research have led to widespread improvements and innovations that improve customer satisfaction. But there has been incredibly little cross-fertilization between the hotel and hospital industries. In this paper, we first consider the changes in the healthcare system that are forcing hospitals to become more concerned with patient satisfaction. We discuss the similarities and differences between the hotel and hospital industries, and then outline several of the unique challenges that neurosurgeons face in taking care of patients and increasing their comfort. We cite specific lessons from the hotel industry that can be applied to patients’ preadmission, check-in, hospital stay, discharge planning, and poststay experiences. We believe that hospitals can and should leverage the successful advances within the hotel industry to improve patient satisfaction, without having to repeat identical research or market experimentation. We hope this will lead to rapid improvements in patient experiences and overall wellbeing. PMID:24818061

  13. What do hotels and hospitals have in common? How we can learn from the hotel industry to take better care of patients.

    PubMed

    Zygourakis, Corinna C; Rolston, John D; Treadway, James; Chang, Susan; Kliot, Michel

    2014-01-01

    Despite widely divergent public perceptions and goals, hotels and hospitals share many core characteristics. Both serve demanding and increasingly well-informed clienteles, both employ a large hierarchy of workers with varying levels of responsibility, and both have payments that are increasingly tied to customer/patient evaluations. In the hotel industry, decades of management experience and market research have led to widespread improvements and innovations that improve customer satisfaction. But there has been incredibly little cross-fertilization between the hotel and hospital industries. In this paper, we first consider the changes in the healthcare system that are forcing hospitals to become more concerned with patient satisfaction. We discuss the similarities and differences between the hotel and hospital industries, and then outline several of the unique challenges that neurosurgeons face in taking care of patients and increasing their comfort. We cite specific lessons from the hotel industry that can be applied to patients' preadmission, check-in, hospital stay, discharge planning, and poststay experiences. We believe that hospitals can and should leverage the successful advances within the hotel industry to improve patient satisfaction, without having to repeat identical research or market experimentation. We hope this will lead to rapid improvements in patient experiences and overall wellbeing.

  14. Best practices to reduce the accident rate hotel

    NASA Astrophysics Data System (ADS)

    García Revilla, M. R.; Kahale Carrillo, D. T.

    2014-10-01

    Examining the available databases and existing tourism organizations can conclude that appear studies on accidents and their relationship with other variables. But in our case we want to assess this relationship in the performance of the hotel in relation to lower the accident rate. The Industrial Safety studies analyzing this accident causes (why they happen), their sources (committed activities), their agents (participants work means), its type (how the events occur or develop), all in order to develop prevention. In our case, as accidents happen because people commit wrongful acts or because the equipment, tools, machinery or workplaces are not in proper conditions, the preventive point of view we analyze through the incidence of workplace accidents hotel subsector. The crash occurs because there is a risk, so that adequate control of it would avoid despite individual factors. Absenteeism or absence from work was taken into account first by Dubois in 1977, as he realized the time lost in the nineteenth century due to the long working hours, which included the holidays. Motivation and job satisfaction were the elements that have been most important in the phenomenon of social psychology.

  15. Comparison of non-prewhitening and Hotelling observer models

    NASA Astrophysics Data System (ADS)

    Burgess, Arthur E.

    1995-04-01

    Recent investigations of human signal detection performance for noise limited tasks have used statistically defined signal or image parameters. The Bayesian ideal observer procedure is then nonlinear and analysis becomes mathematically intractable. Linear, but suboptimal, observer models have been proposed for mathematical convenience. Experiments by Rolland and Barrett involving detection of completely defined signals in white noise superimposed on statistically defined (Lumpy) backgrounds showed that the Fisher-Hotelling model gave a good fit while the simple nonprewhitening (NPW) matched filter gave a poor fit. Burgess showed that the NPW model can be modified to fit their data by adding a spatial frequency filter with response similar to the human contrast sensitivity function. New experimental results will be presented demonstrating that neither model is satisfactory. The results of our experiments done with a variety of spectral densities for the background can be described by a Fisher-Hotelling model modified to include simple circularly symmetric spatial frequency channels as proposed by Myers and Barrett. However, results of our variable viewing distance experiments do not agree with predictions of this simple channelized model. It will be necessary to use a more complex F model with physiologically reasonable spatial frequency channels.

  16. Human annoyance and reactions to hotel room specific noises

    NASA Astrophysics Data System (ADS)

    Everhard, Ian L.

    2004-05-01

    A new formula is presented where multiple annoyance sources and transmission loss values of any partition are combined to produce a new single number rating of annoyance. The explanation of the formula is based on theoretical psychoacoustics and survey testing used to create variables used to weight the results. An imaginary hotel room is processed through the new formula and is rated based on theoretical survey results that would be taken by guests of the hotel. The new single number rating compares the multiple sources of annoyance to a single imaginary unbiased source where absolute level is the only factor in stimulating a linear rise in annoyance [Fidell et al., J. Acoust. Soc. Am. 66, 1427 (1979); D. M. Jones and D. E. Broadbent, ``Human performance and noise,'' in Handbook of Noise Control, 3rd ed., edited by C. M. Harris (ASA, New York, 1998), Chap. 24; J. P. Conroy and J. S. Roland, ``STC Field Testing and Results,'' in Sound and Vibration Magazine, Acoustical Publications, pp. 10-15 (July 2003)].

  17. One for the road: on the utility of citation data for identifying problem hotels.

    PubMed

    Wood, L J; McLean, S; Davidson, J; Montgomery, I M

    1995-01-01

    Drink drivers arrested in Tasmania are routinely asked by police where they had last been drinking, and these data were examined for 716 drivers arrested in Southern Tasmania during a 4-month period in 1992. Nearly half (43%) of arrested drink drivers cited individual hotels as the place where they had last been drinking. This enabled a citation score to be assigned to each of the 82 hotels in metropolitan Hobart. The distribution of citation scores was highly skewed, with eight hotels accounting for 45% of hotel citations, and two accounting for 20%. The hotels' citation scores were compared in relation to the rank order of their licence fees, since better measures of patronage proved unobtainable. Some hotels with small total alcohol sales did appear to have an unexpectedly large number of citations, suggesting less than responsible serving practices. Hoteliers' comments were sought on the interpretation of citation scores, and incorporated into a discussion of the limitations of the data in determining the extent of individual hotel responsibility for drink drivers. Important questions remaining include (1) what is the validity of citations made by drink drivers at the time of arrest; (2) what appropriate and quantifiable denominator can be used to adjust the number of citations to the level of patronage; and (3) what level of citations is too high and requires action?

  18. The reproductive experience of women living in hotels for the homeless in New York City.

    PubMed

    Chavkin, W; Kristal, A; Seabron, C; Guigli, P E

    1987-01-01

    Incidence of low birth weight, infant mortality and attendance at prenatal care were estimated for 401 residents of welfare hotels in New York City and compared to data from housing project residents and the city-wide population. Hotel residents and the pertinent data were ascertained from children's birth certificates dating from January 1982 to June 1984. In 1984 there were 2889 families (3498 adults and 6789 children) housed in 48 privately managed hotels and 7 shelters in the city, set up as emergency housing for the homeless. Most of these families were single women; over 50% were under 25. The racial and ethnic composition of hotel residents was similar to that of housing project tenants. The hotel residents have high birth rates: from 7/month in 1982 to 23/month in 1984. They receive significantly less prenatal care than project or city dwellers; more than half have 0-3 visits. The hotel residents had 2.5 times the likelihood of getting no prenatal care than project tenants, and 4.12 times the likelihood than the citywide population. Mean birth weight for hotel infants was 2979 g; for project infants 3128 g; for city infants 3253 g. Both welfare groups were significantly lower than citywide average birth weights. The infant mortality was 24.9 per 1000 for the hotel group, 16.6 for the project group, and 12.0 for the city population. The stress and inconvenience of living far from social service offices, clinics, schools and shops was considered the likely cause of poor attendance at prenatal care. It was recommended that the city provide on-site health education and care, social and nutrition services in the hotels, and refrigerators for mothers with newborn children.

  19. Early Bird Visions and Telchnology for Space Hotel

    NASA Astrophysics Data System (ADS)

    Amekrane, R.; Holze, C.

    2002-01-01

    The International Space Station was planed for research purposes. In 2001 the first private man, Denis Tito, visited the ISS and the second private man, Mark Shuttleworth is following him. Space pioneers as Wernher von Braun and Sir Arthur C. Clarke had the dream that one day a space station in earth orbit will host tourists. It is evident that the ISS is not designed to host tourists. Therefore the dream is still open. Asking the question "how should a space station should look like to host tourists?" the German Aerospace Society DGLR e.V. initiated in April 2001 a contest under the patronage of . Mr. Joerg Feustel-Buechl, the Director of Manned Spaceflight and Microgravity, European Space Agency (ESA). Because the definition and design of living space is the content of architecture the approach was to gather new ideas from young architects in cooperation with space experts. This contest was directed at students of architecture and the task set was to design a hotel for the earth orbit and to accommodate 220 guests. The contest got the name "Early Bird - Visions of a Space Hotel". The results and models of the student's work were shown in an exhibition in Hamburg/Germany, which was open to the public from September 19th till October 20th 2001. During the summer term 2001 fifty students from the university occupied themselves with the topic, "Design of a hotel for space". During this time seventeen designs were completed. Having specialists, as volunteers, in the field of space in charge meant that it could be ensured that the designs reflected a certain possibility of being able to be realized. Within this interdisciplinary project both parties learned from each other. The 17 different designs were focused on the expectations and needs of a future space tourist. The design are for sure not feasible today, but the designs are in that sense realistic that they could be built in future. This paper will present an overview of the 17 designs as a vision of a future

  20. How Clean Are Hotel Rooms? Part I: Visual Observations vs. Microbiological Contamination.

    PubMed

    Almanza, Barbara A; Kirsch, Katie; Kline, Sheryl Fried; Sirsat, Sujata; Stroia, Olivia; Choi, Jin Kyung; Neal, Jay

    2015-01-01

    Current evidence of hotel room cleanliness is based on observation rather than empirically based microbial assessment. The purpose of the study described here was to determine if observation provides an accurate indicator of cleanliness. Results demonstrated that visual assessment did not accurately predict microbial contamination. Although testing standards have not yet been established for hotel rooms and will be evaluated in Part II of the authors' study, potential microbial hazards included the sponge and mop (housekeeping cart), toilet, bathroom floor, bathroom sink, and light switch. Hotel managers should increase cleaning in key areas to reduce guest exposure to harmful bacteria.

  1. Factors Influencing e-Business Adoption in the Greek Hotel Sector

    NASA Astrophysics Data System (ADS)

    Samanta, Ir.; Kyriazopoulos, P.

    The purpose of this research is to identify the impact of business process improvement in the area of e-marketing in the hotel industry. The research identifies the barriers which block organizational change effort. A sample of thirty hotels in the city of Athens was used.This paper presents a SWOT analysis of the hotel sector, identifying the strengths, weaknesses, opportunities and threats that firms faced in the process of change. The results show that the majority of firms use, to a small extent, the e-marketing concept to improve their communication strategy and reach market segments.

  2. A fuzzy MCDM model with objective and subjective weights for evaluating service quality in hotel industries

    NASA Astrophysics Data System (ADS)

    Zoraghi, Nima; Amiri, Maghsoud; Talebi, Golnaz; Zowghi, Mahdi

    2013-12-01

    This paper presents a fuzzy multi-criteria decision-making (FMCDM) model by integrating both subjective and objective weights for ranking and evaluating the service quality in hotels. The objective method selects weights of criteria through mathematical calculation, while the subjective method uses judgments of decision makers. In this paper, we use a combination of weights obtained by both approaches in evaluating service quality in hotel industries. A real case study that considered ranking five hotels is illustrated. Examples are shown to indicate capabilities of the proposed method.

  3. Shared-savings cuts hotel's losses from EMS removal

    SciTech Connect

    Galvin, C.

    1982-11-08

    A shared-savings contract will minimize the Myrtle Beach, SC Downtown Holiday Inn's losses of replacing a poorly performing Energy Master energy-management system with Scientific Atlanta equipment. The contract with Energy Master Inc. (EMI), which saved Holiday Inn the $80,000 to $90,000 purchase price, also permitted removal (a year after installation) of the equipment when it failed to generate energy savings. A dispute between Associated Energy Consultants (AEC), which was to receive half the savings in exchange for arranging the equipment financing, is described. At $51,745, the 262-point Scientific Atlanta system should have a 1.7-year payback. The hotel's electric bills were $2000 a month lower during the first three months of operation. (DCK)

  4. Search and selection hotel system in Surabaya based on geographic information system (GIS) with fuzzy logic

    NASA Astrophysics Data System (ADS)

    Purbandini, Taufik

    2016-03-01

    Surabaya is a metropolitan city in Indonesia. When the visitor has an interest in Surabaya for several days, then the visitor was looking for lodging that is closest to the interests of making it more efficient and practical. It was not a waste of time for the businessman because of congestion and so we need full information about the hotel as an inn during a stay in Surabaya began name, address of the hotel, the hotel's website, the distance from the hotel to the destination until the display of the map along the route with the help of Google Maps. This system was designed using fuzzy logic which aims to assist the user in making decisions. Design of hotel search and selection system was done through four stages. The first phase was the collection of data and as the factors that influence the decision-making along with the limit values of these factors. Factors that influence covers a distance of the hotel, the price of hotel rooms, and hotel reviews. The second stage was the processing of data and information by creating membership functions. The third stage was the analysis of systems with fuzzy logic. The steps were performed in systems analysis, namely fuzzification, inference using Mamdani, and defuzzification. The last stage was the design and construction of the system. Designing the system using use case diagrams and activity diagram to describe any process that occurs. Development system includes system implementation and evaluation systems. Implementation of mobile with Android-based system so that these applications were user friendly.

  5. Fungal DNA in hotel rooms in Europe and Asia--associations with latitude, precipitation, building data, room characteristics and hotel ranking.

    PubMed

    Norbäck, Dan; Cai, Gui-Hong

    2011-10-01

    There is little information on the indoor environment in hotels. Analysis of fungal DNA by quantitative PCR (qPCR) is a new method which can detect general and specific sequences. Dust was collected through swab sampling of door frames in 69 hotel rooms in 20 countries in Europe and Asia (2007-2009). Five sequences were detected by qPCR: total fungal DNA, Aspergillus and Penicillium DNA (Asp/Pen DNA), Aspergillus versicolor (A. versicolor DNA), Stachybotrys chartarum (S. chartarum DNA) and Streptomyces spp. (Streptomyces DNA). Associations were analysed by multiple linear regression. Total fungal DNA (GM = 1.08 × 10(8) cell equivalents m(-2); GSD = 6.36) and Asp/Pen DNA (GM = 1.79 × 10(7) cell equivalents m(-2); GSD = 10.12) were detected in all rooms. A. versicolor DNA, S. chartarum DNA and Streptomyces DNA were detected in 84%, 28% and 47% of the samples. In total, 20% of the rooms had observed dampness/mould, and 30% had odour. Low latitude (range 1.5-64.2 degrees) was a predictor of Asp/Pen DNA. Seaside location, lack of mechanical ventilation, and dampness or mould were other predictors of total fungal DNA and Asp/Pen DNA. Hotel ranking (Trip Advisor) or self-rated quality of the interior of the hotel room was a predictor of total fungal DNA, A. versicolor DNA and Streptomyces DNA. Odour was a predictor of S. chartarum DNA. In conclusion, fungal DNA in swab samples from hotel rooms was related to latitude, seaside location, ventilation, visible dampness and indoor mould growth. Hotels in tropical areas may have 10-100 times higher levels of common moulds such as Aspergillus and Penicillium species, as compared to a temperate climate zone.

  6. A framework for stochastic simulation of distribution practices for hotel reservations

    SciTech Connect

    Halkos, George E.; Tsilika, Kyriaki D.

    2015-03-10

    The focus of this study is primarily on the Greek hotel industry. The objective is to design and develop a framework for stochastic simulation of reservation requests, reservation arrivals, cancellations and hotel occupancy with a planning horizon of a tourist season. In Greek hospitality industry there have been two competing policies for reservation planning process up to 2003: reservations coming directly from customers and a reservations management relying on tour operator(s). Recently the Internet along with other emerging technologies has offered the potential to disrupt enduring distribution arrangements. The focus of the study is on the choice of distribution intermediaries. We present an empirical model for the hotel reservation planning process that makes use of a symbolic simulation, Monte Carlo method, as, requests for reservations, cancellations, and arrival rates are all sources of uncertainty. We consider as a case study the problem of determining the optimal booking strategy for a medium size hotel in Skiathos Island, Greece. Probability distributions and parameters estimation result from the historical data available and by following suggestions made in the relevant literature. The results of this study may assist hotel managers define distribution strategies for hotel rooms and evaluate the performance of the reservations management system.

  7. "There's no-fresh air there": narratives of smoke exposure among residents of extended-stay hotels.

    PubMed

    Lewinson, Terri; Bryant, Lawrence Oliver

    2015-05-01

    Hotel environments have been identified as places where hospitality workers and patrons are at an increased risk for smoke exposure and associated health hazards. However, little research has been conducted to understand experiences of long-term hotel residents. This article presents narrative accounts of tobacco smoke exposure from 37 residents at extended-stay hotels in a large metropolitan Atlanta county. Residents' narratives included an awareness of smoking as an unhealthy habit but a shared activity that facilitates social engagement at the hotel. Secondhand smoke narratives included descriptions of exposure from roommates and hotel neighbors. Thirdhand smoke narratives included reports of persistent pollution and smoke residue in the hotel environment. These results suggest a need for further research to understand the extent and impact of tobacco smoke exposure among this understudied population. The implications of this research support the efforts of social workers to engage in clean air advocacy and policy making for a vulnerable population.

  8. A Study of the Geographic Origin, Education, and Experience of Hotel General Managers. RHI 590 Individual Project

    DTIC Science & Technology

    1993-04-01

    Department of Restaurant, Hotel, Institutional, and Tourism Management; West Lafayette, IN. Mobil Travel Guide. (1992). Seven regional editions. New...DEPARTMENT OF RESTAURANT, HOTEL, INSTITUTIONAL, AND TOURISM MANAGEMENT 93-19390..9 8 19 1.00’,ltl/i/lI/l•li!l!!•I• II A STUDY OF THE GEOGRAPHIC ORIGIN...DEPARTMENT OF RESTAURANT, HOTEL, INSTITUTIONAL, AND TOURISM MANAGEMENT TABLE OF CONTENTS T A B L E O F C O N T E N T S

  9. Preliminary report: outbreak of Legionnaires disease in a hotel in Calp, Spain, update on 22 February 2012.

    PubMed

    Vanaclocha, H; Guiral, S; Morera, V; Calatayud, M A; Castellanos, M; Moya, V; Jerez, G; Gonzalez, F

    2012-02-23

    Research is ongoing on eighteen cases of Legionellosis, including four deaths, identified among tourists and employees in a hotel in Calp, Spain. Cases occurred during a period of two months, indicating the possibility of a point-source transmission at the hotel. An environmental investigation identified several positive samples in the hotel, which as a precautionary measure, was closed until requested improvements were made. Surveillance measures currently remain active.

  10. The isolation of low frequency impact sounds in hotel construction

    NASA Astrophysics Data System (ADS)

    LoVerde, John J.; Dong, David W.

    2002-11-01

    One of the design challenges in the acoustical design of hotels is reducing low frequency sounds from footfalls occurring on both carpeted and hard-surfaced floors. Research on low frequency impact noise [W. Blazier and R. DuPree, J. Acoust. Soc. Am. 96, 1521-1532 (1994)] resulted in a conclusion that in wood construction low frequency impact sounds were clearly audible and that feasible control methods were not available. The results of numerous FIIC (Field Impact Insulation Class) measurements performed in accordance with ASTM E1007 indicate the lack of correlation between FIIC ratings and the reaction of occupants in the room below. The measurements presented include FIIC ratings and sound pressure level measurements below the ASTM E1007 low frequency limit of 100 Hertz, and reveal that excessive sound levels in the frequency range of 63 to 100 Hertz correlate with occupant complaints. Based upon this history, a tentative criterion for maximum impact sound level in the low frequency range is presented. The results presented of modifying existing constructions to reduce the transmission of impact sounds at low frequencies indicate that there may be practical solutions to this longstanding problem.

  11. [Evaluation of a Legionella outbreak emerged in a recently opening hotel].

    PubMed

    Erdoğan, Haluk; Arslan, Hande

    2013-04-01

    Legionnaires' disease (LD) is a systemic infection caused by Legionella species especially colonized in the water systems. Hotels are common locations in which waterwork-associated sporadic or epidemic legionellosis can be detected. The aim of this study was to evaluate a small Legionella outbreak emerged in a recently opened 600-bed hotel in Alanya, a touristic county in Mediterranean part of Turkey. A 66 years old male patient who stayed in this hotel opened on May 15th, 2009, was admitted to our hospital on May 21st, 2009 with the complaints of high fever, headache and diarrhea lasting for three days. Since chest X-ray revealed non-homogenous density increase in left middle and inferior zone, the patient was diagnosed as atypical pneumoniae and LD was confirmed by positive urinary Legionella antigen test (Card test, BinaxNOW®Legionella Urinary Antigen Test; Alere Co, USA) result. Following the identification of the index case, the records of our hospital were reviewed and revealed another case being treated with the diagnosis of community acquired pneumonia who was also the guest of the same hotel. This patient was then diagnosed as LD by positive urinary antigen test. Since new cases were identified during the following days (May 22, 25 and 26) the Antalya County Health Department and hotel management were informed about a cluster of LD. In addition subsequent investigation for environmental surveillance and water sampling were conducted. The LD diagnosis and environmental inspections were performed according to the procedure described in the guideline from "Turkish Ministry of Health Travel-Associated Legionnaires' Disease Control Programme". Five definitive cases and one presumptive case of LD were identified during the outbreak period (May 20-26, 2009). All of the cases were successfully treated (intravenous ciprofloxacin or levofloxacin or clarithromycin), however one patient died due to sudden death during sleep after being discharged. Since sputum

  12. Suicide by jumping from high-rise hotels. Fulton County, Georgia, 1967-1986.

    PubMed

    Hanzlick, R; Masterson, K; Walker, B

    1990-12-01

    During a 20-year period from 1967 through 1986, 19 suicidal jumps from high-rise hotels (HRHs) accounted for 24% of all fatal jumping episodes and 1% of all suicides in Fulton County, Georgia, U.S.A. The rate of suicidal jumps from HRHs did not increase during the study period. The number of fatal jumps per hotel-year correlated with the height of the interior hotel atrium. The mean age for all victims was 34 years, and 63% of victims were white males. The majority of victims were local residents who were alone when they jumped and were not registered hotel guests. Registered guests tended to jump from the floor on which their room was located whereas nonregistered individuals tended to jump from the upper-most floors in the hotel. Of 19 HRH jumps, 13 occurred from the inside. Suicide notes were found in 37% of cases. HRH jumps were least common between 6 p.m. and midnight, all decedents were dressed in street clothing, only one was heard to have screamed, and all but one were dead on the scene. Alcohol and drug involvement was minimal. We hope that this information will be useful to those who investigate such deaths and to those who study the behavioral manifestations of suicide.

  13. Spatio-temporal Hotelling observer for signal detection from image sequences

    PubMed Central

    Caucci, Luca; Barrett, Harrison H.; Rodríguez, Jeffrey J.

    2010-01-01

    Detection of signals in noisy images is necessary in many applications, including astronomy and medical imaging. The optimal linear observer for performing a detection task, called the Hotelling observer in the medical literature, can be regarded as a generalization of the familiar prewhitening matched filter. Performance on the detection task is limited by randomness in the image data, which stems from randomness in the object, randomness in the imaging system, and randomness in the detector outputs due to photon and readout noise, and the Hotelling observer accounts for all of these effects in an optimal way. If multiple temporal frames of images are acquired, the resulting data set is a spatio-temporal random process, and the Hotelling observer becomes a spatio-temporal linear operator. This paper discusses the theory of the spatio-temporal Hotelling observer and estimation of the required spatio-temporal covariance matrices. It also presents a parallel implementation of the observer on a cluster of Sony PLAYSTATION 3 gaming consoles. As an example, we consider the use of the spatio-temporal Hotelling observer for exoplanet detection. PMID:19550494

  14. Spatio-temporal Hotelling observer for signal detection from image sequences.

    PubMed

    Caucci, Luca; Barrett, Harrison H; Rodriguez, Jeffrey J

    2009-06-22

    Detection of signals in noisy images is necessary in many applications, including astronomy and medical imaging. The optimal linear observer for performing a detection task, called the Hotelling observer in the medical literature, can be regarded as a generalization of the familiar prewhitening matched filter. Performance on the detection task is limited by randomness in the image data, which stems from randomness in the object, randomness in the imaging system, and randomness in the detector outputs due to photon and readout noise, and the Hotelling observer accounts for all of these effects in an optimal way. If multiple temporal frames of images are acquired, the resulting data set is a spatio-temporal random process, and the Hotelling observer becomes a spatio-temporal linear operator. This paper discusses the theory of the spatio-temporal Hotelling observer and estimation of the required spatio-temporal covariance matrices. It also presents a parallel implementation of the observer on a cluster of Sony PLAYSTATION 3 gaming consoles. As an example, we consider the use of the spatio-temporal Hotelling observer for exoplanet detection.

  15. Economic analysis of the water demand in the hotels and restaurants sector: Shadow prices and elasticities

    NASA Astrophysics Data System (ADS)

    Angulo, Ana; Atwi, Majed; Barberán, Ramón; Mur, Jesús

    2014-08-01

    Despite the growing economic importance of tourism, and its impact on relative water shortage, little is known about the role that water plays in the productive process of hotels and restaurants and, therefore, the possible implications of water demand management policy for this sector. This study aims to fill this gap. It is based on the microdata of 676 firms in the sector, operating in the city of Zaragoza (Spain) for a 12 year period. Based on the Translog cost function, we estimate the shadow price of water in the short run and, from a long-run perspective, its direct price elasticity, its cross elasticities relative to labor, capital, and supplies, and its elasticity with respect to the level of output. The results obtained show that water provides sector firms returns that are on average higher than its price, although in the case of hotels the margin is really narrow. This situation provides policy makers with a margin for applying price increases without affecting the sector's viability, with some caution in the case of hotels. Water demand elasticity equals -0.38 in the case of hotels, but it is not significant in the case of restaurants and bar-cafes; hence, only in hotels is there potential for influencing water use patterns, encouraging the resource's conservation through pricing policy. Moreover, capital is a substitutive factor of water, and the elasticity of water with respect to output is 0.40, all of which should also be considered by policy makers in water resource management.

  16. Energy End-Use Patterns in Full-Service Hotels: A Case Study

    SciTech Connect

    Placet, Marylynn; Katipamula, Srinivas; Liu, Bing; Dirks, James A.; Xie, YuLong; Sullivan, Greg; Walent, Jim; Williamson, Rebecca

    2010-06-30

    The U.S. Department of Energy (DOE) recently initiated a program -- Commercial Building Partnerships (CBP) -- to work with private-sector companies in the design of highly-efficient retrofit and new construction projects. Pacific Northwest National Laboratory (PNNL) is conducting a project with a major hotel company to retrofit a full-service, large hotel with the goal of reducing energy consumption by at least 30%. The first step of the project was an intensive metering and monitoring effort aimed at understanding energy end use patterns in the hotel. About 10% of the guest rooms (32), as well as circuits for most of the end uses in public spaces (lighting, elevators, air handlers and other HVAC system components, and various equipment), were equipped with meters. Data are being collected at 1- or 5-minute intervals and downloaded on a monthly basis for analysis. This paper presents results from the first four months of the monitoring effort, which revealed energy end-use consumption patterns, variability of guest room energy use, daily load curves, monthly variations, and other aspects of hotel energy use. Metered end-use data for hotels at this level of detail are not available from any currently-available public sources. This study presents unique information and insight into energy end-use patterns in the lodging sector of commercial buildings and can also serve as a case study of a complex sub-metering project.

  17. Theoretical performance analysis of multislice channelized Hotelling observers

    NASA Astrophysics Data System (ADS)

    Goossens, Bart; Platiša, Ljiljana; Philips, Wilfried

    2012-02-01

    Quality assessment of 3D medical images is becoming increasingly important, because of clinical practice rapidly moving in the direction of volumetric imaging. In a recent publication, three multi-slice channelized Hotelling observer (msCHO) models are presented for the task of detecting 3D signals in multi-slice images, where each multi-slice image is inspected in a so called stack-browsing mode. The observer models are based on the assumption that humans observe multi-slice images in a simple two stage process, and each of the models implement this principle in a different way. In this paper, we investigate the theoretical performance, in terms of detection signal-to-noise-ratio (SNR) of msCHO models, for the task of detecting a separable signal in a Gaussian background with separable covariance matrix. We find that, despite the differences in architecture of the three models, they all have the same asymptotical performance in this task (i.e., when the number of training images tends to infinity). On the other hand, when backgrounds with nonseparable covariance matrices are considered, the third model, msCHOc, is expected to perform slightly better than the other msCHO models (msCHOa and msCHOb), but only when sufficient training images are provided. These findings suggest that the choice between the msCHO models mainly depends on the experiment setup (e.g., the number of available training samples), while the relation to human observers depends on the particular choice of the "temporal" channels that the msCHO models use.

  18. Lack of hygiene routines among patients and family members at patient hotels--a possible route for transmitting puerperal fever.

    PubMed

    Starlander, Gustaf; Lytsy, Birgitta; Melhus, Asa

    2010-07-01

    The use of patient hotels for ambulatory care of women with uncomplicated deliveries has become a routine in Sweden. This report describes a minor outbreak of a group A Streptococcus strain in 2 newly delivered mothers and their newborn babies at a patient hotel.

  19. Meeting Competence Needs in the Hotel and Catering Industry Now and in the Future. Research Report 1992.

    ERIC Educational Resources Information Center

    Walker, Anne, Ed.; Hayter, Roy, Ed.

    The hotel and catering industry in the United Kingdom is estimated to have employed 2,392,000 people in 1990--about 9 percent of the total work force in employment in the country. These figures came from a major study into the skills needs of the hotel and catering industry in relation to the current provision of vocational education. Data are…

  20. Work Conditions and Health and Well-Being of Latina Hotel Housekeepers.

    PubMed

    Hsieh, Yu-Chin; Apostolopoulos, Yorghos; Sönmez, Sevil

    2016-06-01

    Hotel housekeepers are exposed to a plethora of disproportionately high work-induced hazards that can lead to adverse health consequences. Latina hotel housekeepers are rendered particularly vulnerable to elevated occupational hazards and resultant health strains due to their socioeconomic status, immigration status, language barriers, and lack of access to healthcare services. The findings from the 27 interviews with Latina hotel housekeepers indicated that the interviewees were exposed to physical, chemical, and social hazards in the workplace and suffered musculoskeletal injuries. In terms of psychological wellness, the time pressure of cleaning rooms quickly and work-related stress stemming from workplace mistreatment emerged as major work-related stressors. Recommendations are made for the introduction of multilevel interventions designed to prevent work-related injuries and illnesses and to promote healthier workplaces.

  1. A room with a viewpoint revisited: descriptive norms and hotel guests' towel reuse behavior.

    PubMed

    Bohner, Gerd; Schlüter, Lena E

    2014-01-01

    Field experiments on descriptive norms as a means to increase hotel guests' towel reuse [1] were replicated and extended. In two hotels in Germany (Study 1: N = 724; Study 2: N = 204), descriptive norm messages suggesting that 75% of guests had reused their towels, or a standard message appealing to environmental concerns, were placed in guests' bathrooms. Descriptive norm messages varied in terms of proximity of the reference group ("hotel guests" vs. "guests in this room") and temporal proximity (currently vs. two years previous). Reuse of towels was unobtrusively recorded. Results showed that reuse rates were high overall and that both standard and descriptive norm messages increased reuse rates compared to a no-message baseline. However, descriptive norm messages were not more effective than the standard message, and effects of proximity were inconsistent across studies. Discussion addresses cultural and conceptual issues in comparing the present findings with previous ones.

  2. [Duration of sick-leave and the moment of recovery in the hotel industry].

    PubMed

    Folgerø, I S; Larsen, S

    1991-09-10

    The paper addresses the problem of sick leave in the hotel industry. It was hypothesized that there would be a tendency for granted sick leaves to include weekends, thus imposing an additional financial burden on the hotel in question. A total of 401 medical certificates from a large city hotel were reviewed. According to these certificates one third of the patients regained their health between Sunday and Monday. Of the patients with "short" sick leaves (less than a fortnight), 40% recovered between Sunday and Monday. The average duration of the sick leave for this group was 1.3 days longer than that of the patients whose sick leaves ended on other days of the week. The results are discussed in terms of the ambiguous position of the medical practitioner.

  3. A gastroenteritis outbreak due to norovirus associated with a Colorado hotel.

    PubMed

    Dippold, Laura; Lee, Robin; Selman, Carol; Monroe, Steve; Henry, Chuck

    2003-12-01

    Describing the system components of norovirus outbreaks is important in understanding how to prevent future outbreaks. Investigation of these components includes environmental, epidemiologic, and laboratory perspectives. This study describes how an investigation from these three perspectives was conducted and the significance of each component in understanding norovirus outbreaks. On May 23, 2000, members of a professional group attending two meetings at a local hotel in Englewood, Colorado, began to complain of gastrointestinal illness. Sixty-nine illnesses were reported among 133 attendees. Eight hotel employees also complained of illness. Staff from the Tri-County Health Department and the Centers for Disease Control and Prevention investigated the outbreak. Three stool specimens collected from ill attendees contained norovirus. While the epidemiologic component did not identify a specific vehicle of transmission, the environmental investigation revealed food-handling practices, food handler perceptions, and hotel policies that may have contributed to disease transmission.

  4. Welfare Hotels. Uses, Costs, and Alternatives. Briefing Report to the Chairman, Subcommittee on Oversight and Investigations, Committee on Energy and Commerce, House of Representatives.

    ERIC Educational Resources Information Center

    General Accounting Office, Washington, DC. Div. of Human Resources.

    "Welfare hotels" are commercially-owned, single- or multi-story hotels or motels providing shelter to a clientele composed exclusively or primarily of homeless families receiving public assistance. They often provide inadequate physical conditions and services. Information in the following areas is given about welfare hotels: (1)…

  5. Optimum contracted-for water supply for hotels in arid coastal regions.

    PubMed

    Lamei, A; von Münch, E; van der Zaag, P; Imam, E

    2009-01-01

    Hotels in arid coastal areas use mainly desalinated water for their domestic water demands, and treated wastewater for irrigating green areas. Private water companies supply these hotels with their domestic water needs. There is normally a contractual agreement stating a minimum requirement that has to be supplied by the water company and that the hotel management has to pay for regardless of its actual consumption ("contracted-for water supply"). This paper describes a model to determine what value a hotel should choose for its contracted-for water supply in order to minimize its total annual water costs. An example from an arid coastal tourism-dominated city is presented: Sharm El Sheikh, Egypt.The managers of hotels with expected high occupancy rates (74% and above) can contract for more than 80%. On the other hand, hotels with expected lower occupancy rates (60% and less) can contract for less than 70% of the peak daily domestic water demand. With a green area ratio of 40 m(2)/room or less, an on-site wastewater treatment plant can satisfy the required irrigation demand for an occupancy rate as low as 42%. Increasing the ratio of green irrigated area to 100 m(2)/room does not affect the contracted-for water supply at occupancy rates above 72%; at lower occupancy rates, however, on-site treated wastewater is insufficient for irrigating the green areas. Increasing the green irrigated area to 120 m(2)/room increases the need for additional water, either from externally sourced treated wastewater or potable water. The cost of the former is much lower than the latter (0.58 versus 1.52 to 2.14 US$/m(3) in the case study area).

  6. A towel less: social norms enhance pro-environmental behavior in hotels.

    PubMed

    Reese, Gerhard; Loew, Kristina; Steffgen, Georges

    2014-01-01

    Previous research has shown that normative appeals to engage in environmentally friendly behavior were most effective when they were accompanied by a provincial norm (e.g., when norms matched individuals' immediate situational circumstances). Analyzing hotel guests' towel-use during their stay, the current study tests whether messages employing provincial norms were more effective in reducing towel-use than standard environmental messages. In line with previous findings, guests of two hotels used significantly fewer towels when provincial normative appeals--rather than standard environmental messages--were communicated. These findings corroborate to the body of research demonstrating the power of social norms on environmental behavior.

  7. Comparison of patrons of hotels with early opening and standard hours.

    PubMed

    Smith, D I

    1986-02-01

    A comparison was made of 72 men who were patrons in hotels with 6 A.M. or 7 A.M. opening, with a control group of 87 men interviewed in nearby hotels with 10 A.M. opening. The two groups were very similar on biographical characteristics, yet the men in the early-opening group consumed significantly more alcohol, had more drinking sessions, spent longer in drinking, and had significantly higher SMAST scores. The early opening was apparently facilitating problem drinking.

  8. Outbreaks of infectious intestinal disease associated with person to person spread in hotels and restaurants.

    PubMed

    McDonnell, R J; Wall, P G; Adak, G K; Evans, H S; Cowden, J M; Caul, E O

    1995-09-15

    Twenty-eight outbreaks of infectious intestinal disease, reported as being transmitted mainly by the person to person route, were identified in association with retail catering premises, such as hotels, restaurants, and public houses, in England and Wales between 1992 and 1994. Five thousand and forty-eight people were at risk in these outbreaks and 1234 were affected. Most of the outbreaks (over 90%) occurred in hotels. Small round structured viruses were the most commonly detected pathogens. Diarrhoea and vomiting were common symptoms and most of the outbreaks occurred in the summer months. Control measures to contain infectious individuals and improved hygiene measures are necessary to contain such outbreaks.

  9. Hotel water consumption at a seasonal mass tourist destination. The case of the island of Mallorca.

    PubMed

    Deyà Tortella, Bartolomé; Tirado, Dolores

    2011-10-01

    While it is true that tourism is one of the main driving forces behind economic growth in several world regions, it is also true that tourism can have serious negative environmental impacts, especially with regard to water resources. The tourist water demand can generate big problems of sustainability, mainly in those regions where water is scarce, as occurs in most coastal and small island destinations where a large part of world tourism is concentrated. Given the shortage of literature on the subject, further research into the tourist water demand is required, with particular attention to the hotel sector, since hotels are the most popular option for tourists, displaying higher levels of water consumption. The main purpose of this study is to develop a model to analyse hotel water consumption at a mature sun and sand destination with a strong seasonal pattern and scarcity of water; characteristics shared by some of the world's main tourist destinations. Our model includes a set of different hotel variables associated with physical, seasonal and management-related factors and it improves on the capacity to explain water consumption at such destinations. Following a hierarchical regression methodology, the model is empirically tested through a survey distributed to managers of a representative sample of hotels on the island of Mallorca. From the obtained results, interesting recommendations can be made for both hotel managers and policy makers. Among these, it should be highlighted that the strategic move contemplated by many mature destinations towards a higher quality, low-season model could have significant negative effects in terms of the sustainability of water resources. Our results also conclude that managerial decisions, like the system of accommodation that is offered (i.e. the proliferation of the "all-inclusive" formula, both at mature and new destinations), could give rise to the same negative effect. Development of water saving initiatives (usually

  10. Improving service quality in NHS Trust hospitals: lessons from the hotel sector.

    PubMed

    Desombre, T; Eccles, G

    1998-01-01

    This article looks to review recent practice undertaken within the UK hotel sector to improve customer service, and suggests ideals that could be implemented within National Health (NHS) Trust hospitals. At a time of increasing competition, hotel firms are using service enhancement as a means to gain competitive advantage, and therefore developing a range of techniques to measure levels of service quality improvement. With continued change in the health service, where greater focus now lies with patient satisfaction, so there is a requirement for managers to adapt techniques presently being offered in other service industries to improve levels of customer service and ensure patients are targeted to define their levels of satisfaction.

  11. The Role of Mathematics in Hotel, Catering and Institutional Management HND and FM Courses.

    ERIC Educational Resources Information Center

    Roberts, I. M.; Ineson, Elizabeth M.

    1980-01-01

    Research was conducted from the viewpoints of students, teaching staff, and industry in relation to mathematical abilities of students taking hotel, catering, and institutional management courses, content and structure of Higher National Diploma and Final Membership courses, industrial applications, and learning strategies. (CT)

  12. Evaluation of Hotel, Restaurant, and Institutional Management Graduates: A Ten Year Review.

    ERIC Educational Resources Information Center

    Johnson, Dona, Comp.; And Others

    A study of graduates from the Hotel, Restaurant, and Institutional Management program at St. Louis Community College at Forest Park was conducted, primarily in order to elicit information from graduates regarding potentially effective recruitment methods for minority groups and women. The study also sought to obtain evaluation of course curriculum…

  13. The Special Needs of Homeless Children: Early Intervention at a Welfare Hotel.

    ERIC Educational Resources Information Center

    Grant, Roy

    1991-01-01

    This case study of 72 homeless families and their 78 children in day care at a large welfare hotel in New York City evaluates the children's health status, separation and attachment, sleep patterns, eating patterns, emotional status, attention span, gross motor development, speech and language development, and cognitive development. (JDD)

  14. 'Bee hotels' as tools for native pollinator conservation: a premature verdict?

    PubMed

    MacIvor, J Scott; Packer, Laurence

    2015-01-01

    Society is increasingly concerned with declining wild bee populations. Although most bees nest in the ground, considerable effort has centered on installing 'bee hotels'--also known as nest boxes or trap nests--which artificially aggregate nest sites of above ground nesting bees. Campaigns to 'save the bees' often promote these devices despite the absence of data indicating they have a positive effect. From a survey of almost 600 bee hotels set up over a period of three years in Toronto, Canada, introduced bees nested at 32.9% of sites and represented 24.6% of more than 27,000 total bees and wasps recorded (47.1% of all bees recorded). Native bees were parasitized more than introduced bees and females of introduced bee species provisioned nests with significantly more female larva each year. Native wasps were significantly more abundant than both native and introduced bees and occupied almost 3/4 of all bee hotels each year; further, introduced wasps were the only group to significantly increase in relative abundance year over year. More research is needed to elucidate the potential pitfalls and benefits of using bee hotels in the conservation and population dynamics of wild native bees.

  15. Colonization of Legionella species in Turkish baths in hotels in Alanya, Turkey.

    PubMed

    Erdogan, Haluk; Arslan, Hande

    2015-05-01

    This study evaluated the prevalence of Legionella species in water samples collected from Turkish baths in hotels in Alanya, Turkey, from August 2003 to September 2013. Water samples were collected in 100-mL sterile containers and then concentrated by filtration. Heat treatment was used to eliminate other microorganisms from the samples, which were then spread on Legionella-selective-buffered charcoal yeast extract alpha (BCYE-α) agar and on BCYE-α agar supplemented with glycine, vancomycin, polymyxin, and cycloheximide. Cysteine-dependent colonies were identified by latex agglutination. In total, 135 samples from 52 hotels with Turkish baths were evaluated. Legionella species were identified in 11/52 (21.2%) hotels and 18/135 (13.3%) samples. The most frequently isolated species was Legionella pneumophila, with most isolates belonging to serogroups 6 (55.6%) and 1 (22.2%). The colony count was <100 colony-forming units (CFU) mL(-1) in nine samples, from 100 to 1000 CFU mL(-1) in six samples, and >1000 CFU mL(-1) in three samples. These findings suggest that the hot water systems of Turkish baths in hotels must be viewed as a possible source of travel-associated Legionnaires' disease, and preventative measures should be put in place.

  16. Tourists’ attitudes towards ban on smoking in air-conditioned hotel lobbies in Thailand

    PubMed Central

    Viriyachaiyo, V; Lim, A

    2009-01-01

    Background: Thailand is internationally renowned for its stringent tobacco control measures. In Thailand, a regulation banning smoking in air-conditioned hotel lobbies was issued in late 2006, causing substantial apprehension within the hospitality industry. A survey of tourists’ attitudes toward the ban was conducted. Methods: A cross-sectional survey of 5550 travellers staying in various hotels in Bangkok, Surat Thani, Phuket, Krabi and Songkhla provinces, October 2005 to December 2006. Travellers aged 15 years or older with a check-in duration of at least one day and willing to complete the questionnaire were requested by hotel staff to fill in the 5-minute questionnaire at check-in or later at their convenience. Results: Secondhand cigarette smoke was recognised as harmful to health by 89.7% of respondents. 47.8% of travellers were aware of the Thai regulation banning smoking in air-conditioned restaurants. 80.9% of the respondents agreed with the ban, particularly female non-smokers. 38.6% of survey respondents indicated that they would be more likely to visit Thailand again because of the regulation, 53.4% that the regulation would not affect their decision and 7.9% that they would be less likely to visit Thailand again. Conclusion: Banning smoking in air-conditioned hotel lobbies in Thailand is widely supported by tourists. Enforcement of the regulation is more likely to attract tourists than dissuade them from holidaying in Thailand. PMID:19364754

  17. REEP Hotels/Chambers Federal Workplace Literacy Project. April 1, 1990-December 31, 1991.

    ERIC Educational Resources Information Center

    Arlington County Public Schools, VA. REEP, Arlington Education and Employment Program.

    In an expansion of an earlier National Workplace Literacy Program project, this document reports on a workplace literacy model operated by the Arlington Education and Employment Program (REEP) that includes the Alexandria and Arlington, Virginia Public Schools, the chambers of commerce of both cities, and 14 local hotels. The project provided…

  18. The effect of the water tariff structures on the water consumption in Mallorcan hotels

    NASA Astrophysics Data System (ADS)

    Deyà-Tortella, Bartolomé; Garcia, Celso; Nilsson, William; Tirado, Dolores

    2016-08-01

    Tourism increases water demand, especially in coastal areas and on islands, and can also cause water shortages during the dry season and the degradation of the water supply. The aim of this study is to evaluate the impact of water price structures on hotel water consumption on the island of Mallorca (Spain). All tourist municipalities on the island use different pricing structures, such as flat or block rates, and different tariffs. This exogenous variation is used to evaluate the effect of prices on water consumption for a sample of 134 hotels. The discontinuity of the water tariff structure and the fixed rate, which depends on the number of hotel beds, generate endogeneity problems. We propose an econometric model, an instrumental variable quantile regression for within artificial blocks transformed data, to solve both problems. The coefficients corresponding to the price variables are not found to be significantly different from zero. The sign of the effect is negative, but the magnitude is negligible: a 1% increase in all prices would reduce consumption by an average of only 0.024%. This result is probably due to the small share of water costs with respect to the total hotel operational costs (around 4%). Our regression model concludes that the introduction of water-saving initiatives constitutes an effective way to reduce consumption.

  19. Family Hotel Businesses: Strategic Planning and the Need for Education and Training

    ERIC Educational Resources Information Center

    Peters, Mike; Buhalis, Dimitrios

    2004-01-01

    Small businesses dominate the tourism and hospitality industry worldwide and are of critical importance for the competitiveness of destinations. Small family hotel businesses are characterised by a number of specific business processes which generate particular training and educational needs. It is increasingly clear that small businesses are not…

  20. Devolving HRM and HRD to Line managers: The Case of Hilton International's UK Hotels

    ERIC Educational Resources Information Center

    Maxwell, Gillian; Watson, Sandra

    2004-01-01

    This paper explores line manager responsibility for human resource management (HRM) and human resource development (HRD) in an international hotel organisation. The results identify a strong support system for line managers in relation to training and good relations with HR specialists. However, less evident is senior management support coupled…

  1. Analyzing the Training and Internship Needs Assessment of Verbal Communication Skills amongst Hotel Practitioners

    ERIC Educational Resources Information Center

    Rahim, Suzana Ab.; Tazijan, Farina

    2011-01-01

    There is a need to expose the learners in the hospitality industry to real workplace requirement in terms of communication skills. In view of its importance, human resource managers, researchers and educators in the field of hospitality management or the hotel practitioners have to pay more serious attention to it. Thus, it is pertinent that both…

  2. Respiratory and ocular symptoms among employees of a hotel indoor waterpark resort--Ohio, 2007.

    PubMed

    2009-02-06

    During January--March 2007, the Warren County Combined Health District (WCCHD) received 665 reports of respiratory and eye irritation from patrons and lifeguards at a hotel indoor waterpark resort in Ohio. Tests revealed normal water chemistry and air chlorine concentrations, and exposure to airborne trichloramine in the waterpark was suspected as the cause of the symptoms. Because of the number of symptom reports and WCCHD's limited ability to measure trichloramine, the district requested an investigation by CDC's National Institute for Occupational Safety and Health (NIOSH). This report describes the results of that investigation, which revealed that trichloramine concentrations in the waterpark ranged from below the limit of detection to 1.06 mg/m3, and some concentrations were at levels that have been reported to cause irritation symptoms (>/=0.5 mg/m3). Lifeguards reported significantly more work-related symptoms (e.g., cough, wheezing, shortness of breath, chest tightness, and eye irritation) than unexposed hotel employees. Lifeguards also reported significantly more eye irritation and cough on days when hotel occupancy was high versus low. Insufficient air movement and distribution likely led to accumulation of trichloramine and exacerbation of symptoms. Based on recommendations to increase air movement and distribution at pool deck level, hotel management modified the ventilation system extensively, and subsequently no new cases were reported to WCCHD. The results of this investigation emphasize the importance of appropriate design and monitoring of ventilation and water systems in preventing illness in indoor waterparks.

  3. Perceptions toward the Value of Higher Education for Hotel Professionals in Las Vegas: A Case Study

    ERIC Educational Resources Information Center

    Deel, Gary Lee

    2015-01-01

    This study concerns a qualitative investigation of the views toward higher education and its importance to hospitality career success among hotel professionals in the Las Vegas, Nevada area. Existing literature supported the premise that education may be important to professional career success in several different ways, and that values concerning…

  4. The Matching Process in E-Mentoring: A Case Study in Luxury Hotels

    ERIC Educational Resources Information Center

    Simmonds, David; Lupi, Anne Marie Zammit

    2010-01-01

    Purpose: This paper seeks to examine the effectiveness of an innovative e-mentoring programme introduced in an international group of luxury hotels. Design/methodology/approach: The paper employs the survey method, with quantitative and qualitative data analysis. The research model was developed from a literature review. Findings: While mentoring…

  5. Genomic Investigation of a Legionellosis Outbreak in a Persistently Colonized Hotel

    PubMed Central

    Sánchez-Busó, Leonor; Guiral, Silvia; Crespi, Sebastián; Moya, Víctor; Camaró, María L.; Olmos, María P.; Adrián, Francisco; Morera, Vicente; González-Morán, Francisco; Vanaclocha, Hermelinda; González-Candelas, Fernando

    2016-01-01

    Objectives: A long-lasting legionellosis outbreak was reported between November 2011 and July 2012 in a hotel in Calpe (Spain) affecting 44 patients including six deaths. Intensive epidemiological and microbiological investigations were performed in order to detect the reservoirs. Methods: Clinical and environmental samples were tested for the presence and genetic characterization of Legionella pneumophila. Six of the isolates were subjected to whole-genome sequencing. Results: Sequencing of 14 clinical and 260 environmental samples revealed sequence type (ST) 23 as the main responsible strain for the infections. This ST was found in the spa pool, from where it spread to other hotel public spaces, explaining the ST23 clinical cases, including guests who had not visited the spa. Uncultured clinical specimens showed profiles compatible with ST23, ST578, and mixed patterns. Profiles compatible with ST578 were obtained by direct sequencing from biofilm samples collected from the domestic water system, which provided evidence for the source of infection for non ST23 patients. Whole genome data from five ST23 strains and the identification of different STs and Legionella species showed that different hotel premises were likely colonized since the hotel opening thus explaining how different patients had been infected by distinct STs. Conclusions: Both epidemiological and molecular data are essential in the investigation of legionellosis outbreaks. Whole-genome sequencing data revealed significant intra-ST variability and allowed to make further inference on the short-term evolution of a local colonization of L. pneumophila. PMID:26834713

  6. Project EXCEL: Sheraton Palace Hotel, Laundry Department. A Beginning Laundry Curriculum.

    ERIC Educational Resources Information Center

    Career Resources Development Center, Inc., San Francisco, CA.

    Project EXCEL is a federally-funded workplace literacy program involving hotel enterprises in the San Francisco (California) Bay area. Its focus is on identification and instruction of literacy skills essential to job success for limited-English-proficient (LEP) workers. Training is intended to enable employees to understand written work orders,…

  7. French for "Hotellies": A Recently Instituted Course at the Cornell School of Hotel Administration.

    ERIC Educational Resources Information Center

    Grandjean-Levy, Andree

    The Cornell School of Hotel Administration in collaboration with the Department of Modern Languages and Linguistics offers a course in French for a small group of students who have had the equivalent of at least two semesters of college French. The course emphasizes oral/aural French with very little class time spent on grammar study. Grammar…

  8. 11. 4TH FLOOR, HOTEL SOAP LINE No. 6 TO NORTHEAST, ...

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

    11. 4TH FLOOR, HOTEL SOAP LINE No. 6 TO NORTHEAST, WITH WRAPPER (LEFT), PRESS (CENTER), AND CUTTER (RIGHT, BEHIND CHUTE); BUCKET CONVEYOR AT RIGHT MOVED WASTE FROM PRESS TO 5TH FLOOR FOR RE-MANUFACTURE - Colgate & Company Jersey City Plant, Building No. B-14, 54-58 Grand Street, Jersey City, Hudson County, NJ

  9. Workforce Education. Hotel and Motel Workers. A Section 353 Demonstration Project.

    ERIC Educational Resources Information Center

    Polk County Public Schools, Bartow, FL.

    This guide provides an overall view of a program designed to educate adult basic education (ABE) and English-as-a-Second-Language (ESL) students in job-related, language-oriented skills vital to their positions in the hotel/motel industry. The program was designed for the employees of Grenelefe Resort and Conference Center in Haines City, Florida,…

  10. Basic Skills in the Hotel & Food Service Industries. Workforce & Workplace Literacy Series. Revised.

    ERIC Educational Resources Information Center

    BCEL Brief, 1993

    1993-01-01

    This report contains a list of 21 contacts and 9 references concerned with workplace literacy programs in the hotel and food service industries. Each listing includes addresses and telephone numbers, prices if applicable, and a brief description of the resource or materials. The materials listed are mostly reports of workplace literacy projects in…

  11. Career Preparation for Hotel-Motel Management and Services. Grade 11, Phase I.

    ERIC Educational Resources Information Center

    Montgomery County Public Schools, Rockville, MD.

    Suggestions arising from a curriculum development workshop led to a curriculum in hotel-motel management and services for high school students which aims to provide them with an opportunity to explore careers in the lodging and hospitality industries. Students will spend half the time in school study of three required subjects and the other half…

  12. ESL for Hotel/Hospitality Industry. Level: Advanced Beginner/Intermediate.

    ERIC Educational Resources Information Center

    Western Suffolk County Board of Cooperative Educational Services, Northport, NY.

    This document contains 16 lesson plans for an advanced beginning and intermediate course in work-related English for non-English- or limited-English-speaking entry-level employees in the hotel and hospitality industry. Course objectives are as follows: helping participants understand and use job-specific vocabulary; receive and understand…

  13. 76 FR 69753 - Agency Information Collection Activities: Proposed Collection; Comment Request, Federal Hotel and...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-11-09

    ...; Comment Request, Federal Hotel and Motel Fire Safety Declaration Form AGENCY: Federal Emergency Management....regulations.gov . FOR FURTHER INFORMATION CONTACT: Bruce Hensler, Fire Program Specialist, FEMA/U.S. Fire... accommodation meeting minimum requirements for protection of life from fire; the list is known as the...

  14. Occupations in the Hotel Tourist Sector within the European Community. A Comparative Analysis.

    ERIC Educational Resources Information Center

    Peroni, Giovanni; Guerra, Duccio

    This report contains a directory of job profiles in the tourist/hotel sector that is based on seven national monographs. It provides an instrument for comparing factors that characterize practitioners working in the sector in Germany, Spain, France, Greece, Italy, Portugal, and the United Kingdom. A methodological note discusses study objectives,…

  15. Inventory analysis and carbon footprint of coastland-hotel services: A Spanish case study.

    PubMed

    Puig, Rita; Kiliç, Eylem; Navarro, Alejandra; Albertí, Jaume; Chacón, Lorenzo; Fullana-I-Palmer, Pere

    2017-04-03

    Tourism is a key industry in the Spanish economy. Spain was in the World top three ranking by international tourist arrivals and by income in 2015. The development of the tourism industry is essential to maintain the established economic system. However, if the environmental requirements were not taken into account, the country would face a negative effect on depletion of local environmental resources from which tourism depends. This case study evaluates, through a life cycle perspective, the average carbon footprint of an overnight stay in a Spanish coastland hotel by analyzing 14 two-to-five-stars hotels. Inventory and impact data are analyzed and presented both for resource use and greenhouse gases emissions, with the intention of helping in the environmental decision-making process. The main identified potential hotspots are electricity and fuels consumption (6 to 30kWh/overnight stay and 24 to 127MJ/overnight stay respectively), which are proportional to the number of stars and unoccupancy rate and they produce more than 75% of the impact. It is also revealed that voluntary implementation of environmental monitoring systems (like EMAS regulation) promotes collection of more detailed and accurate data, which helps in a more efficient use of resources. A literature review on LCA and tourism is also discussed. Spanish hotels inventory data presented here for the first time will be useful for tourism related managers (destination managers, policy makers and hotel managers among others) to calculate sustainability key indicators, which can lead to achieve real sustainable-tourism goals. Further data collection will be needed in future projects to gather representative data from more hotels, other accommodation facilities and also other products/services offered by tourist sector in Spain (like transport of tourists, food and beverage, culture-sports & recreation and others).

  16. "Front Desk? Send Me a Computer!" The Hotel and Tourism Sector: New Technology Spawns a Revolution in Travel Jobs.

    ERIC Educational Resources Information Center

    World of Work, 1997

    1997-01-01

    The computer and new technologies are revolutionizing the hotel, catering, and tourism businesses. There is consensus that formal training for these changes falls short of new requirements and that schools are having difficulty keeping up. (JOW)

  17. Biogas from bio-waste-potential for an ecological waste and energy management in resort hotels

    SciTech Connect

    Steinbach, D.; Schultheis, A.

    1996-12-31

    This paper gives an overview about waste management in holiday resorts. The objective is to determine the composition of waste and the specific waste quantities per guest. This data represents the basis for planning recycling measures and corresponding treatment facilities. The sorting analyses show the great potential of organic material suitable for biological treatment. Because of the characteristics (water content, structure) of these organic materials, composting is not as suitable as fermentation. Fermentation tests with hotel bio-waste turned out a much higher rate of biogas compared with communal bio-waste. Until now, biogas as a possibility of regenerative energy, has not been taken into consideration for big hotels or holiday resorts. Using biogas as an additional source of energy and the fermentation products as fertilizer would be a further step to an ecologically beneficial tourism.

  18. The Impact of e-Customer Relationship Marketing in Hotel Industry

    NASA Astrophysics Data System (ADS)

    Samanta, Irene

    The present research investigates the extent to which Greek hotels had developed the electronic customer relationship marketing (E-CRM). The study verifies the practices that frequently appear in relationship marketing process within online operations or whether their Internet presence mainly depends on the basic actions of "supplying information" and "reservations". Also, it investigates the effects of e-CRM system on customer loyalty and satisfaction as well as the impact of relationship marketing practices to customer retention and acquisition. They have understood the importance of using electronic channels instead of traditional ones to implement their marketing strategies. Thus, e-crm system has assisted hotel business to manage more effectively their reservations and serve their customers as fast and as effective as possible. They did not seem to apply many of the relationship marketing strategies to emphasize customer retention and continual satisfaction because of difficulties in staff training.

  19. Bit-plane-channelized hotelling observer for predicting task performance using lossy-compressed images

    NASA Astrophysics Data System (ADS)

    Schmanske, Brian M.; Loew, Murray H.

    2003-05-01

    A technique for assessing the impact of lossy wavelet-based image compression on signal detection tasks is presented. A medical image"s value is based on its ability to support clinical decisions such as detecting and diagnosing abnormalities. Image quality of compressed images is, however, often stated in terms of mathematical metrics such as mean square error. The presented technique provides a more suitable measure of image degradation by building on the channelized Hotelling observer model, which has been shown to predict human performance of signal detection tasks in noise-limited images. The technique first decomposes an image into its constituent wavelet subband coefficient bit-planes. Channel responses for the individual subband bit-planes are computed, combined,and processed with a Hotelling observer model to provide a measure of signal detectability versus compression ratio. This allows a user to determine how much compression can be tolerated before signal detectability drops below a certain threshold.

  20. Analytical approximations to the Hotelling trace for digital x-ray detectors

    NASA Astrophysics Data System (ADS)

    Clarkson, Eric; Pineda, Angel R.; Barrett, Harrison H.

    2001-06-01

    The Hotelling trace is the signal-to-noise ratio for the ideal linear observer in a detection task. We provide an analytical approximation for this figure of merit when the signal is known exactly and the background is generated by a stationary random process, and the imaging system is an ideal digital x-ray detector. This approximation is based on assuming that the detector is infinite in extent. We test this approximation for finite-size detectors by comparing it to exact calculations using matrix inversion of the data covariance matrix. After verifying the validity of the approximation under a variety of circumstances, we use it to generate plots of the Hotelling trace as a function of pairs of parameters of the system, the signal and the background.

  1. Geothermal district heating and cooling of hotel/casinos in downtown Reno, Nevada

    SciTech Connect

    Cerci, Y.; Kanoglu, M.; Cengel, Y.A.; Turner, R.H.

    1996-12-31

    In this paper, potential revenues from the proposed geothermal district heating/cooling system for the hotel/casino complexes in downtown Reno, Nevada are estimated by analyzing their actual electricity and natural gas bills during 1993 through 1994. The geothermal system appears to be feasible, and financially very attractive. The geothermal district system can meet the entire heating and cooling requirements of the hotel/casinos, generating total potential revenues of $3,486,000 per year. Also, other buildings around the downtown area such as Saint Mary`s Hospital, several motels, business complexes, Washoe County School District Building, and even the UNR campus will add extra potential revenues, if these buildings are connected to the geothermal grid. Since most buildings around the downtown use central heating and cooling system, the retrofit costs for the both system should be minimal.

  2. Evaluation of the Implementation of Good Handling Practices in Food and Beverage Areas of Hotels.

    PubMed

    Serafim, A L; Hecktheuer, L H R; Stangarlin-Fiori, L; Medeiros, L B; Martello, L; Machado, C E

    2015-11-01

    Because of the major international-level events that have recently been held in Brazil, concerns about the sensory and hygienic-sanitary conditions of food have increased. The objective of this study was to evaluate the implementation of good handling practices in food and beverage areas of hotels, with and without outsourced professional intervention. We evaluated 19 food and beverage areas in hotels in Porto Alegre, Rio do Sul, Brazil, using a checklist that was developed by a municipal surveillance team based on existing laws for good handling practices. The evaluation was done by a skilled professional in the food safety area on two occasions, at the beginning of the study (January to May 2013) and at the end (July to November 2014), and the establishments were classified as good, regular, or poor. After the baseline evaluation, an action plan listing the noncompliance found at each location was given to those responsible for the establishments, and a period of 1 year 6 months was stipulated for improvements to be made. In the repeat evaluation, those responsible for the establishments were asked whether they had hired an outsourced professional to assist them in the improvements. The hotels showed improvement during the repeat evaluation, but a significant increase in the percentage of overall adequacy was seen only in the food and beverages areas of the 12 hotels that used the intervention of an outsourced professional. The better percentage of adequacy in establishments with outsourced professional intervention underlines the importance of an external and impartial view of routine activities in the implementation of good handling practices.

  3. Critical Infrastructure Protection: How to Assess and Provide Remedy to Vulnerabilities in Telecom Hotels

    DTIC Science & Technology

    2006-09-01

    infrastructure due to convergence. Not only are phone calls to mom affected in a failure, but also all internet traffic. This includes B2B (Business to...infrastructure in the United States. The study focuses on “telecom hotels”—large facilities that house several network carriers, telephone and internet service...data center, gateway, network exchange center, commercial internet exchange, mondo condo, internet farm, cyber hotel and data bunker. It is a

  4. 10. 4TH FLOOR, HOTEL SOAP LINE No. 6 TO SOUTHWEST, ...

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

    10. 4TH FLOOR, HOTEL SOAP LINE No. 6 TO SOUTHWEST, WITH AUTOMATIC CUTTER (LEFT), PRESS (CENTER), AND WRAPPER (RIGHT); LARGE CHUTE AT CENTER FROM 5TH FLOOR BINS TO 3RD FLOOR SOAP MILLS; OVERHEAD AND FLOOR (LOWER RIGHT) FINISHED GOODS CONVEYORS TO G BLOCK (HAER NO. NJ-71-NN) - Colgate & Company Jersey City Plant, Building No. B-14, 54-58 Grand Street, Jersey City, Hudson County, NJ

  5. What is a health worker? How spa therapists in a Norwegian health hotel understand their work.

    PubMed

    Anderssen, Jorid

    2016-01-01

    In Norway, as in many other wealthy countries, the number of health-related services that are being offered outside of the health sector is increasing. The present paper is based on qualitative interviews that were conducted with providers of health-related services at a commercial health hotel in Norway. The hotel is marketed as a health hotel - that is, a place for people with health problems and for those who need relaxation and an escape from their stressful everyday lives. The paper discusses whether the providers of this kind of service consider it a health service or if they distinguish and distance themselves from the health system. The interviews showed that they consider themselves health workers and refer to themselves as therapists. Even though they use therapy in the health sector as a model, they distinguish themselves from therapists in the health sector. They do not want to treat what they call sick people. Most of their therapy is directed toward cultivating or improving people's bodies and souls. These service providers think that they contribute to improving their guests' health by teaching them how to take care of themselves; enjoying oneself (for instance, by receiving skin treatment or a massage) is an important aspect of good health. According to the therapists, modern-day women, in particular, are often worn-out, and they deserve, and are entitled, to enjoy themselves. In these ways, the therapists use health to legitimize their services, and they challenge the current understanding of health.

  6. A large common-source outbreak of norovirus gastroenteritis in a hotel in Singapore, 2012.

    PubMed

    Raj, P; Tay, J; Ang, L W; Tien, W S; Thu, M; Lee, P; Pang, Q Y; Tang, Y L; Lee, K Y; Maurer-Stroh, S; Gunalan, V; Cutter, J; Goh, K T

    2017-02-01

    An outbreak of gastroenteritis affected 453 attendees (attack rate 28·5%) of six separate events held at a hotel in Singapore. Active case detection, case-control studies, hygiene inspections and microbial analysis of food, environmental and stool samples were conducted to determine the aetiology of the outbreak and the modes of transmission. The only commonality was the food, crockery and cutlery provided and/or handled by the hotel's Chinese banquet kitchen. Stool specimens from 34 cases and 15 food handlers were positive for norovirus genogroup II. The putative index case was one of eight norovirus-positive food handlers who had worked while they were symptomatic. Several food samples and remnants tested positive for Escherichia coli or high faecal coliforms, aerobic plate counts and/or total coliforms, indicating poor food hygiene. This large common-source outbreak of norovirus gastroenteritis was caused by the consumption of contaminated food and/or contact with contaminated crockery or cutlery provided or handled by the hotel's Chinese banquet kitchen.

  7. Assessment of a fluorescence-enhanced optical imaging system using the Hotelling observer

    NASA Astrophysics Data System (ADS)

    Sahu, Amit K.; Joshi, Amit; Kupinski, Matthew A.; Sevick-Muraca, Eva M.

    2006-08-01

    This study represents a first attempt to assess the detection capability of a fluorescence-enhanced optical imaging system as quantified by the Hotelling observer. The imaging system is simulated by the diffusion approximation of the time-dependent radiative transfer equation, which describes near infra-red (NIR) light propagation through clinically relevant tissue volumes. The random structures in the background are introduced using a lumpy-object model as a representation of anatomical structure as well as non-uniform distribution of disease markers. The systematic errors and noise associated with the actual experimental conditions are incorporated into the simulated boundary measurements to acquire imaging data sets. A large number of imaging data sets are considered in order to perform Hotelling observer studies. We find that the signal-to-noise ratio (SNR) of Hotelling observer (i) decreases as the strength of lumpy perturbations in the background increases, (ii) decreases as the target depth increases, and (iii) increases as excitation light leakage decreases, and reaches a maximum for filter optical density values of 5 or higher.

  8. Key facilitators and best practices of hotel-style room service in hospitals.

    PubMed

    Sheehan-Smith, Lisa

    2006-04-01

    This qualitative study sought to identify the features, advantages, and disadvantages of hotel-style room service; the barriers to, and facilitators for, implementing the process; and "best practices." The study took place in four heterogeneous hospitals. Participants included hospital administrators, managers, and room-service employees. Data-collection methods included semi-structured interviews, observations, and document analysis. Common features of hotel-style room service were meal delivery within 30 to 45 minutes, a restaurant-style menu, procedures to feed ineligible patients, tray assembly on demand, scripting, and waitstaff uniforms for room-service employees. The major barrier to implementing room service was obtaining nursing support. The key facilitators were the hospital's service-oriented culture, using a multidisciplinary planning team, engaging nursing departments early in the planning stages, and intense customer-service training of room-service employees. The overwhelming advantage was patients' control over their food choices. The main disadvantage was cost. Initial best practices in hotel-style room service include: (a) taking a multidisciplinary team approach for developing and implementing the process, (b) customer-service training, (c) using a customer-driven menu, (d) wearing waitstaff uniforms, and (e) using carts with airpots for dispensing hot beverages.

  9. Norovirus outbreak associated with a hotel in the west of Ireland, 2006.

    PubMed

    Michel, A; Fitzgerald, R; Whyte, D; Fitzgerald, A; Beggan, E; O'Connell, N; Greally, T

    2007-07-01

    An outbreak of gastrointestinal disease (nausea, vomiting or diarrhoea) occurred among a party of wedding guests, staff and other guests in a hotel in the west of Ireland, in October 2006. Upon notification, a multi-disciplinary outbreak control team was convened to investigate and control the outbreak. In all, 98 people were ascertained ill. The median duration of illness was 48 hours. The attack rate ranged between 48 and 85%. The hotel voluntarily notified health authorities and co-operated fully with investigation and control measures. Strict prevention and control measures were instituted promptly, including air ventilation, enhanced hand hygiene, isolation of cases, temporary "cooked food only", temporary alternative accommodation and specialised cleaning. Three cases of norovirus infection were laboratory-confirmed. There was no evidence of food- or water-borne transmission. Clinical and epidemiological findings indicated person-to-person transmission of norovirus. This report highlights the potential for large social gatherings to facilitate the spread of viral gastroenteritis by person-to-person transmission and via contaminated environment. Effective community management of this outbreak appears to have prevented its having an impact on local acute hospital services. The authors conclude that in addition to the existing national guidelines on the management of outbreaks of norovirus in healthcare settings, agreed guidelines for the management of norovirus outbreaks in the hotel and tourism industry are needed in Ireland.

  10. The world's largest photovoltaic hotel roof project: A case study of the Mauna Lani Bay Hotel PowerGuard{reg_sign} system

    SciTech Connect

    Shugar, D.S.; Saito, R.

    1999-07-01

    This paper presents design, performance, and economic feasibility information of the Mauna Lani Bay Hotel and Bungalows 100 KWp photovoltaic (PV) roofing system supplied by PowerLight Corporation. The system, called PowerGuard{reg_sign}, was installed in May 1998. Several months of operating data are presented together with information regarding the value of the system. The project achieved several milestones for building-integrated PV (BIPV), such as (1) the largest BIPV project in the USA, (2) the largest PV project in Hawaii by a factor of five, (3) a demonstration of the practicality for constructing BIPV in a premium resort location during normal operations, and (4) a strong economic return for BIPV in tropical applications.

  11. Employee Relations. A Guide and Reference Book for Those Involved or Training to Be Involved in Employee Relations in the Hotel and Catering Industry. Seventh Edition.

    ERIC Educational Resources Information Center

    Martin, Rodney; Hayter, Roy, Ed.

    This guide and reference book is designed to help those involved or training to be involved in employee relations in the hotel and catering industry. Chapter 1 attempts to define employee relations. Chapter 2 describes the institutions and parties involved in employee relations in the hotel and catering industry. The focus of chapter 3 is on…

  12. [Changes of bacterial community structure on reusing domestic sewage of Daoxianghujing Hotel to landscape water].

    PubMed

    Zhu, Jing-nan; Wang, Xiao-dan; Zhai, Zhen-hua; Ma, Wen-lin; Li, Rong-qi; Wang, Xue-lian; Li, Yan-hong

    2010-05-01

    A 16S rDNA library was used to evaluate the bacterial diversity and identify dominant groups of bacteria in different treatment pools in the domestic sewage system of the Beijing Daoxianghujing Hotel. The results revealed that there were many types of bacteria in the hotel domestic sewage, and the bacterial Shannon-Weaver diversity index was 3.12. In addition, epsilon Proteobacteria was found to be the dominant group with the ratio of 32%. In addition, both the CFB phylum, Fusobacteria, gamma Proteobacteria and Firmicutes were also reached to 9%-15%. After treated with the reclaimed water station, the bacterial Shannon-Weaver diversity index was reduced to 2. 41 and beta Proteobacteria became the dominant group and occupied 73% of the total clones. However, following artificial wetland training, the bacterial Shannon-Weaver diversity index in the sample increased to 3.38, Actinobacteria arrived to 33% and became the most dominant group; Cyanobacteria reached to 26%, and was the second dominant group. But, the control sample comprised 38% Cyanobacteria, and mainly involved in Cyanobium, Synechoccus and Microcystis, with ratios of 47.1%, 17.6% and 8.8%, respectively. Some bacteria of Microcystis aenruginosa were also detected, which probably resulted in the light bloom finally. Therefore, the bacterial diversity and community structures changed in response to treatment of the hotel domestic sewage; there was no cyanobacteria bloom explosion in the treated water. This study will aid in investigation the changes of microbial ecology in different types of water and providing the useful information for enhancing the cyanobacteria blooms control from ecological angle.

  13. Flame retardants in indoor dust and air of a hotel in Japan.

    PubMed

    Takigami, Hidetaka; Suzuki, Go; Hirai, Yasuhiro; Ishikawa, Yukari; Sunami, Masakiyo; Sakai, Shin-ichi

    2009-05-01

    Occurrence of flame retardants (FRs) in the indoor environment of highly flame-retarded public facilities is an important concern from the viewpoint of exposure because it is likely that FRs are used to a greater degree in these facilities than in homes. For this study, brominated flame-retardants (BFRs) and organophosphate flame-retardants and plasticizers (OPs), and brominated dibenzo-p-dioxins/furans (PBDD/DFs) were measured in eight floor dust samples taken from a Japanese commercial hotel that was assumed to have many flame-retardant materials. Concentrations of polybrominated diphenylethers (PBDEs) and hexabromocyclododecanes (HBCDs) varied by about two orders of magnitude, from 9.8-1700 ng/g (median of 1200 ng/g) and from 72-1300 ng/g (median of 740 ng/g), respectively. Concentrations of the two types of BFRs described above were most dominant among the investigated BFRs in the dust samples. It is inferred that BFR and PBDD/DF concentrations are on the same level as those in house and office dust samples reported based on past studies. Regarding concentrations of 11 OPs, 7 OPs were detected on the order of micrograms per gram, which are equivalent to or exceed the BFR concentrations such as PBDEs and HBCDs. Concentrations of the investigated compounds were not uniform among dust samples collected throughout the hotel: concentrations differed among floors, suggesting that localization of source products is associated with FR concentrations in dust. Passive air sampling was also conducted to monitor BFRs in the indoor air of hotel rooms: the performance of an air cleaner placed in the room was evaluated in terms of reducing airborne BFR concentrations. Monitoring results suggest that operation of an appropriate air cleaner can reduce both gaseous and particulate BFRs in indoor air.

  14. Hotel-based ambulatory care for complex cancer patients: a review of the University College London Hospital experience.

    PubMed

    Sive, Jonathan; Ardeshna, Kirit M; Cheesman, Simon; le Grange, Franel; Morris, Stephen; Nicholas, Claire; Peggs, Karl; Statham, Paula; Goldstone, Anthony H

    2012-12-01

    Since 2005, University College London Hospital (UCLH) has operated a hotel-based Ambulatory Care Unit (ACU) for hematology and oncology patients requiring intensive chemotherapy regimens and hematopoietic stem cell transplants. Between January 2005 and 2011 there were 1443 patient episodes, totaling 9126 patient days, with increasing use over the 6-year period. These were predominantly for hematological malignancy (82%) and sarcoma (17%). Median length of stay was 5 days (range 1-42), varying according to treatment. Clinical review and treatment was provided in the ACU, with patients staying in a local hotel at the hospital's expense. Admission to the inpatient ward was arranged as required, and there was close liaison with the inpatient team to preempt emergency admissions. Of the 523 unscheduled admissions, 87% occurred during working hours. An ACU/hotel-based treatment model can be safely used for a wide variety of cancers and treatments, expanding hospital treatment capacity, and freeing up inpatient beds for those patients requiring them.

  15. Tuberculosis screening among homeless persons with AIDS living in single-room-occupancy hotels.

    PubMed

    Layton, M C; Cantwell, M F; Dorsinville, G J; Valway, S E; Onorato, I M; Frieden, T R

    1995-11-01

    Congregate facilities for homeless persons with the acquired immunodeficiency syndrome (AIDS) are often endemic for tuberculosis. We evaluated tuberculosis screening methods at single-room-occupancy hotels housing persons with AIDS. Residents were screened by cross matching the New York City Tuberculosis Registry, interviewing for tuberculosis history, skin testing, and chest radiography. Cases were classified as either previously or newly diagnosed. Among the 106 participants, 16 (15%) previously diagnosed tuberculosis cases were identified. Participants' tuberculosis histories were identified by the questionnaire (100%) or by registry match (69%). Eight participants (50%) were noncompliant with therapy. These findings prompted the establishment of a directly observed therapy program on site.

  16. Expanding Midscale Solar: Examining the Economic Potential, Barriers, and Opportunities at Offices, Hotels, Warehouses, and Universities

    SciTech Connect

    Bird, Lori; Gagnon, Pieter; Heeter, Jenny

    2016-09-01

    The midscale market for solar photovoltaics (PV), defined as behind-the-meter systems between 100 kW and 2 MW, has grown more slowly than other PV market segments in recent years. A number of key barriers have impeded growth, including tenant and landlord split incentives, contracting challenges, the mismatch in building lease and PV financing terms, and high transaction costs relative to project sizes. This report explores prospects for expansion of the midscale solar market, with a focus on four building segments: offices, hotels, warehouses, and universities.

  17. The effects of converting wheels on housekeeping carts in a large urban hotel. Program evaluation.

    PubMed

    Intilli, H

    1999-10-01

    Occupational and environmental health nurses can identify the causes of injuries and use analytical skills to show how the prevention of a problem can save the company money and demonstrate a caring attitude from management. Nurses can expand their traditional roles to position themselves as both advocates for the employees and profit enhancers to management as demonstrated by this program evaluation project. Initial outcomes included improved employee morale and reduced soft tissue injuries in hotel housekeeping employees. Changes in the workplace made by a proactive occupational and environmental health nurse and a committed management can reap rewards beneficial for both the employer and the work force.

  18. Covariance approximation for fast and accurate computation of channelized Hotelling observer statistics

    SciTech Connect

    Bonetto, Paola; Qi, Jinyi; Leahy, Richard M.

    1999-10-01

    We describe a method for computing linear observer statistics for maximum a posteriori (MAP) reconstructions of PET images. The method is based on a theoretical approximation for the mean and covariance of MAP reconstructions. In particular, we derive here a closed form for the channelized Hotelling observer (CHO) statistic applied to 2D MAP images. We show reasonably good correspondence between these theoretical results and Monte Carlo studies. The accuracy and low computational cost of the approximation allow us to analyze the observer performance over a wide range of operating conditions and parameter settings for the MAP reconstruction algorithm.

  19. [To smoke or not to smoke, in restaurants, hotels, and bars].

    PubMed

    López-Antuñano, Francisco Javier; Tovar-Guzmán, Victor José

    2002-01-01

    A MEDLINE search was conducted to identify relevant references, to review the information on adverse effects of tobacco smoking and environmental tobacco smoke (ETS). Occupational exposure to ETS causes significant damages to food industry workers. High levels of mutagenic substances have been demonstrated in restaurant air as well as in the urine samples from those workers. Exposition to 3-aminophenyl, a hemoglobin-associated carcinogen. The best way to protect these workers is the reduction of tobacco smoking in restaurants, hotels, bars and taverns. In restaurant workers, ETS attributable risk for lung cancer is evident.

  20. The ambivalence of the work of the hotel managers: an approach to ergonomics.

    PubMed

    de Gois Leite, Cyntia Maria; de Carvalho, Ricardo Josématos

    2012-01-01

    This article uses the contributions of ergonomics to understand the work performed by hotel managers. The concern to understand the job of managers is something new in the ergonomics and few studies address this issue, especially in what concerns the work of hotel managers and its aspects of performance and health, which is the focus of this article. Through a literature review on the subject, it is sought to understand the managers' work activity, the impacts on their health and their organizational performance, as managers take an ambivalent position in organizations, since they have to deal directly with the demands of upper and lower hierarchies in a context of high competition, organizational changes and user requirements. It is then inferred there is a risk of increased work density for managers, bringing negative consequences to their health and organizational performance. This phenomenon, still poorly covered by ergonomics, contributes to a certain invisibility of the manager's work in society as a whole, when the manager may suffer from health problems, which are also common in certain populations of workers who do not take the managerial function.

  1. Application of the Hotelling and ideal observers to detection and localization of exoplanets

    PubMed Central

    Caucci, Luca; Barrett, Harrison H.; Devaney, Nicholas; Rodríguez, Jeffrey J.

    2008-01-01

    The ideal linear discriminant or Hotelling observer is widely used for detection tasks and image-quality assessment in medical imaging, but it has had little application in other imaging fields. We apply it to detection of planets outside of our solar system with long-exposure images obtained from ground-based or space-based telescopes. The statistical limitations in this problem include Poisson noise arising mainly from the host star, electronic noise in the image detector, randomness or uncertainty in the point-spread function (PSF) of the telescope, and possibly a random background. PSF randomness is reduced but not eliminated by the use of adaptive optics. We concentrate here on the effects of Poisson and electronic noise, but we also show how to extend the calculation to include a random PSF. For the case where the PSF is known exactly, we compare the Hotelling observer to other observers commonly used for planet detection; comparison is based on receiver operating characteristic (ROC) and localization ROC (LROC) curves. PMID:18059905

  2. HIV type 1 subtypes among bar and hotel workers in Moshi, Tanzania.

    PubMed

    Kiwelu, Ireen E; Renjifo, Boris; Chaplin, Beth; Sam, Noel; Nkya, Watoky M M M; Shao, John; Kapiga, Saidi; Essex, Max

    2003-01-01

    The HIV-1 prevalence among bar and hotel workers in Tanzania suggests they are a high-risk group for HIV-1 infection. We determined the HIV-1 subtype of 3'-p24/5'-p7 gag and C2-C5 env sequences from 40 individuals representing this population in Moshi. Genetic patterns composed of A(gag)-A(env), C(gag)-C(env), and D(gag)-D(env) were found in 19 (48.0%), 8 (20.0%), and 3 (8.0%) samples, respectively. The remaining 10 samples (25%) had different subtypes in gag and env, indicative of intersubtype recombinants. Among these recombinants, two contained sequences from HIV-1 subsubtype A2, a new genetic variant in Tanzania. Five bar and hotel workers may have been infected with viruses from a common source, based on phylogenetic analysis. The information obtained by surveillance of HIV-1 subtypes in a high-risk population should be useful in the design and evaluation of behavioral, therapeutic, and vaccine trial interventions aimed at reducing HIV-1 transmission.

  3. Precarious employment, working hours, work-life conflict and health in hotel work.

    PubMed

    McNamara, Maria; Bohle, Philip; Quinlan, Michael

    2011-01-01

    Precarious or temporary work is associated with adverse outcomes including low control over working hours, work-life conflict and stress. The rise in precarious employment is most marked in the service sector but little research has been done on its health effects in this sector. This study compares permanent and temporary workers in the hotel industry, where working hours are highly variable. Survey data from 150 workers from eight 3-Star hotels in urban and regional areas around Sydney were analyzed. Forty-five per cent were male and 52 per cent were female. Fifty four per cent were permanent full-time and 46 per cent were temporary workers. The effects of employment status on perceived job security, control over working hours, and work-life conflict are investigated using PLS-Graph 3.0. The effects of control over working hours, on work-life conflict and subsequent health outcomes are also explored. Temporary workers perceived themselves as less in control of their working hours, than permanent workers (β = .27). However, they also reported lower levels of work intensity (β = .25) and working hours (β = .38). The effects of low hours control (β = .20), work intensity (β = .29), and excessive hours (β = .39) on work-life conflict (r² = .50), and subsequent health effects (r² = .30), are illustrated in the final structural equation model.

  4. Salmonella Litchfield outbreak associated with a hotel restaurant--Atlantic City, New Jersey, 2007.

    PubMed

    2008-07-18

    On July 10, 2007, the Pennsylvania Department of Health notified the New Jersey Department of Health and Senior Services (NJDHSS) of three culture-confirmed cases of Salmonella Litchfield infection with matching pulsed-field gel electrophoresis (PFGE) patterns. Data from PulseNet, the national molecular subtyping network for foodborne disease surveillance, confirmed 11 cases (including the three from Pennsylvania) of this rarely identified Salmonella serotype in five states during a 5-week period; seven of the 11 patients had reported recent travel history to Atlantic City, New Jersey. This report describes the subsequent investigation led by NJDHSS and the Atlantic City Health Department (ACHD), which associated the outbreak with a hotel restaurant in Atlantic City. In all, 30 confirmed or probable cases of illness with S. Litchfield infection were identified among persons from eight states who had eaten at the hotel restaurant, including 10 restaurant food handlers. Investigators concluded that the outbreak most likely was associated with fruit salad, particularly the honeydew melon component, and that contamination likely resulted from an ill food handler. This investigation illustrates the potential for recurring food contamination by ill and asymptomatic food handlers and underscores the utility of PulseNet to link illnesses that might appear unrelated.

  5. Application of the Hotelling and ideal observers to detection and localization of exoplanets.

    PubMed

    Caucci, Luca; Barrett, Harrison H; Devaney, Nicholas; Rodríguez, Jeffrey J

    2007-12-01

    The ideal linear discriminant or Hotelling observer is widely used for detection tasks and image-quality assessment in medical imaging, but it has had little application in other imaging fields. We apply it to detection of planets outside of our solar system with long-exposure images obtained from ground-based or space-based telescopes. The statistical limitations in this problem include Poisson noise arising mainly from the host star, electronic noise in the image detector, randomness or uncertainty in the point-spread function (PSF) of the telescope, and possibly a random background. PSF randomness is reduced but not eliminated by the use of adaptive optics. We concentrate here on the effects of Poisson and electronic noise, but we also show how to extend the calculation to include a random PSF. For the case where the PSF is known exactly, we compare the Hotelling observer to other observers commonly used for planet detection; comparison is based on receiver operating characteristic (ROC) and localization ROC (LROC) curves.

  6. Starting Up Your Own Business in the Hotel and Catering Industry. A Self-Help Guide from the Small Business Service of the Hotel and Catering Industry Training Board.

    ERIC Educational Resources Information Center

    Hotel and Catering Training Board, Wembley (England).

    This guide is intended to assist the potential small business proprietor in successfully starting a business in the hotel and catering industry. It is divided into five sections. The first section discusses factors to be considered in making the initial decision of whether or not to seek self-employment in the industry (options, potential…

  7. Towards Customer-Driven Management in Hospitality Education: A Case Study of the Higher Hotel Institute, Cyprus.

    ERIC Educational Resources Information Center

    Varnavas, Andreas P.; Soteriou, Andreas C.

    2002-01-01

    Presents and discusses the approach used by the Higher Hotel Institute in Cyprus to incorporate total quality management through establishment of a customer-driven management culture in its hospitality education program. Discusses how it collects and uses service-quality related data from future employers, staff, and students in pursuing this…

  8. Development and application of an integrated indoor air quality audit to an international hotel building in Taiwan.

    PubMed

    Kuo, Nae-Wen; Chiang, Hsin-Chen; Chiang, Che-Ming

    2008-12-01

    Indoor air quality (IAQ) has begun to surface as an important issue that affects the comfort and health of people; however, there is little research concerned about the IAQ monitoring of hotels up to now. Hotels are designed to provide comfortable spaces for guests. However, most complaints related to uncomfortable thermal environment and inadequate indoor air quality appear. In addition, microbial pollution can affect the health of tourists such as the Legionnaire's disease and SARS problems. This study is aimed to establish the comprehensive IAQ audit approach for hotel buildings with portable equipment, and one five-star international hotel in Taiwan was selected to exam this integrated approach. Finally, four major problems are identified after the comprehensive IAQ audit. They are: (1) low room temperature (21.8 degrees C), (2) insufficient air exchange rate (<1.5 h(-1)), (3) formaldehyde contamination (>0.02 ppm), and (4) the microbial pollution (total bacteria: 2,624-3,799 CFU/m(3)). The high level of formaldehyde may be due to the emission from the detergent and cleaning agents used for housekeeping.

  9. Building a University-Community Partnership to Explore Health Challenges among Residents at Extended-Stay Hotels

    ERIC Educational Resources Information Center

    Lewinson, Terri

    2014-01-01

    Extended-stay hotels are housing solutions for some older adults on the fringe of street homelessness. Research indicates that these environments can produce negative health outcomes for older adults. Strategies for managing negative environmental conditions must be identified to help older adults manage health outcomes. This paper describes a…

  10. Checking into China's cow hotels: have policies following the milk scandal changed the structure of the dairy sector?

    PubMed

    Mo, D; Huang, J; Jia, X; Luan, H; Rozelle, S; Swinnen, J

    2012-05-01

    China's milk scandal is well known for causing the nation's largest food safety crisis and for its effect on thousands of children. Less, however, is known about the effect on the other victim: China's small dairy farmers. Although small backyard producers were not the ones that added melamine to the milk supply, the incomes of dairy farmers fell sharply after the crisis. In response, one of the actions taken by the government was to encourage small dairy producers to check into production complexes that were supposed to supply services, new technologies, and provide for easy/bulk procurement of the milk produced by the cows of the farmers. Because both farmers and their cows were living (and working) away from home, in the rest of the paper we call these complexes cow hotels. In this paper we examine the dynamics of China's dairy production structure before and after the milk scandal. In particular, we seek to gain a better understanding about how China's policies have been successful in encouraging farmers to move from the backyard into cow hotels. We also seek to find if larger or smaller farmers respond differently to these policy measures. Using data from a sample of farmers from dairy-producing villages in Greater Beijing, our empirical analysis finds that 1 yr after the milk scandal, the dairy production structure changed substantially. Approximately one quarter (26%) of the sample checked into cow hotels after the milk scandal, increasing from 2% before the crisis. Our results also demonstrate that the increase in cow hotel production can largely be attributed to China's dairy policies. Finally, our results suggest that the effects of government policy differ across farm sizes; China's dairy policies are more likely to persuade larger farms to join cow hotels. Apparently, larger farms benefit more when they join cow hotels. Overall, these results suggest that during the first year after the crisis, the government policies were effective in moving some of

  11. Consumer Decision-Making Based on Review Websites: Are There Differences Between Choosing a Hotel and Choosing a Physician?

    PubMed Central

    Germeni, Evi; Schulz, Peter J

    2016-01-01

    Background Web users are increasingly encouraged to rate and review consumer services (eg, hotels, restaurants) and, more recently, this is also the case for physicians and medical services. The resemblance in the setup and design of commercial rating websites (CRWs) and Web-based physician rating websites (PRWs) raises the question of whether choice-making processes based on the two types of websites could also be similar. Objective This qualitative study sought to explore the extent to which consumer decision making based on Web-based reviews is the same for consumer services (ie, choice of a hotel) and health services (ie, choice of a pediatrician), while providing an in-depth understanding of potential differences or similarities. Methods Between June and August 2015, we carried out a total of 22 qualitative interviews with young parents residing in the German-speaking part of Switzerland. Participants were invited to complete 2 choice tasks, which involved (1) choosing a hotel based on the commercial Web-based rating website TripAdvisor and (2) selecting a pediatrician based on the PRW Jameda. To better understand consumers’ thought processes, we instructed participants to “think aloud”, namely to verbalize their thinking while sorting through information and reaching decisions. Using a semistructured interview guide, we subsequently posed open-ended questions to allow them to elaborate more on factors influencing their decision making, level of confidence in their final choice, and perceived differences and similarities in their search for a hotel and a physician. All interviews were recorded, transcribed, and analyzed using an inductive thematic approach. Results Participants spent on average 9:57 minutes (standard deviation=9:22, minimum=3:46, maximum=22:25) searching for a hotel and 6:17 minutes (standard deviation=4:47, minimum=00:38, maximum=19:25) searching for a pediatrician. Although the choice of a pediatrician was perceived as more important

  12. A Model for Sustainable Building Energy Efficiency Retrofit (BEER) Using Energy Performance Contracting (EPC) Mechanism for Hotel Buildings in China

    NASA Astrophysics Data System (ADS)

    Xu, Pengpeng

    Hotel building is one of the high-energy-consuming building types, and retrofitting hotel buildings is an untapped solution to help cut carbon emissions contributing towards sustainable development. Energy Performance Contracting (EPC) has been promulgated as a market mechanism for the delivery of energy efficiency projects. EPC mechanism has been introduced into China relatively recently, and it has not been implemented successfully in building energy efficiency retrofit projects. The aim of this research is to develop a model for achieving the sustainability of Building Energy Efficiency Retrofit (BEER) in hotel buildings under the Energy Performance Contracting (EPC) mechanism. The objectives include: • To identify a set of Key Performance Indicators (KPIs) for measuring the sustainability of BEER in hotel buildings; • To identify Critical Success Factors (CSFs) under EPC mechanism that have a strong correlation with sustainable BEER project; • To develop a model explaining the relationships between the CSFs and the sustainability performance of BEER in hotel building. Literature reviews revealed the essence of sustainable BEER and EPC, which help to develop a conceptual framework for analyzing sustainable BEER under EPC mechanism in hotel buildings. 11 potential KPIs for sustainable BEER and 28 success factors of EPC were selected based on the developed framework. A questionnaire survey was conducted to ascertain the importance of selected performance indicators and success factors. Fuzzy set theory was adopted in identifying the KPIs. Six KPIs were identified from the 11 selected performance indicators. Through a questionnaire survey, out of the 28 success factors, 21 Critical Success Factors (CSFs) were also indentified. Using the factor analysis technique, the 21 identified CSFs in this study were grouped into six clusters to help explain project success of sustainable BEER. Finally, AHP/ANP approach was used in this research to develop a model to

  13. Individual- and Organization-Level Work-to-Family Spillover Are Uniquely Associated with Hotel Managers' Work Exhaustion and Satisfaction

    PubMed Central

    Lee, Soomi; Davis, Kelly D.; Neuendorf, Claudia; Grandey, Alicia; Lam, Chun Bun; Almeida, David M.

    2016-01-01

    Purpose: Building on the Conservation of Resources theory, this paper examined the unique and interactive associations of negative and positive work-to-family spillover (NWFS and PWFS, respectively) at the individual and organizational level with hotel managers' work exhaustion and satisfaction, beyond job demands and supervisors' leadership style. Design/Methodology/Approach: Guided by the levels of analysis framework, we first tested the unique associations of NWFS and PWFS with emotional exhaustion and job satisfaction at the individual level (571 hotel managers), beyond job demands supervisors' leadership style. Second, using multilevel modeling, we tested the climate effects of NWFS and PWFS on emotional exhaustion and job satisfaction aggregated at the organizational level (41 hotels). Third, we examined the role of the organizational climate of PWFS in the associations of individual-level NWFS with emotional exhaustion and job satisfaction. Findings: Beyond the effects of psychological job demands and supervisor's transformational leadership, at the individual level, hotel managers who experienced higher NWFS than other managers reported more exhaustion and lower job satisfaction, whereas those with higher PWFS reported less exhaustion and higher satisfaction. At the organizational level, working in hotels where the average level of NWFS was higher than other hotels was associated with feeling more exhaustion of the individual members; working in hotels with higher PWFS was associated with feeling less exhaustion. The negative link between individual-level NWFS and job satisfaction was buffered when organization-level PWFS was higher, compared to when it was lower. Originality/Value: This study moves beyond a focus on traditional job characteristics, toward considering individual and organizational experiences in the work-family interface as unique predictors of work exhaustion and satisfaction. Strengths of the study include illuminating organizational work

  14. Integrating wastewater reuse in water resources management for hotels in arid coastal regions - Case Study of Sharm El Sheikh, Egypt.

    PubMed

    Lamei, A; van der Zaag, P; Imam, E

    2009-01-01

    Hotels in arid coastal areas use mainly desalinated water (using reverse osmosis) for their domestic water supply, and treated wastewater for irrigating green areas. Private water companies supply these hotels with their potable and non-potable water needs. There is normally a contractual agreement stating a minimum amount of water that has to be supplied by the water company and that the hotel management has to pay for regardless of its actual consumption ("contracted-for water supply"). Hotels have to carefully analyse their water requirements in order to determine which percentage of the hotel's peak water demand should be used in the contract in order to reduce water costs and avoid the risk of water shortage. This paper describes a model to optimise the contracted-for irrigation water supply with the objective function to minimise total water cost to hotels. It analyses what the contracted-for irrigation water supply of a given hotel should be, based on the size of the green irrigated area on one hand and the unit prices of the different types of water on the other hand. An example from an arid coastal tourism-dominated city is presented: Sharm El Sheikh (Sharm), Egypt. This paper presents costs of wastewater treatment using waste stabilisation ponds, which is the prevailing treatment mechanism in the case study area for centralised plants, as well as aerobic/anaerobic treatment used for decentralised wastewater treatment plants in the case study area. There is only one centralised wastewater treatment plant available in the city exerting monopoly and selling treated wastewater to hotels at a much higher price than the actual cost that a hotel would bear if it treated its own wastewater. Contracting for full peak irrigation demand is the highest total cost option. Contracting for a portion of the peak irrigation demand and complementing the rest from desalination water is a cheaper option. A better option still is to complement the excess irrigation demand

  15. Space-Hotel EARLY BIRD - A Visionary Prospect of a Space Station

    NASA Astrophysics Data System (ADS)

    Amekrane, R.; Holze, C.

    2002-01-01

    rachid.amekrane@astrium-space.com/Fax: +49 421 539-24801, cholze@zarm.uni-bremen.de/Fax: The International Space Station was planed for research purposes. In 2001 the first private man, Denis Tito,visited the ISS and the second private man, Mark Shuttleworth is following him. Space pioneers as Wernher von Braun, Sir Arthur C. Clarke had the dream that one day a space station in earth orbit will host tourists. It is evident that the ISS is not designed to host tourists. Therefore this dream is still open. Asking the question "how should a space station should look like to host tourists?" the German Aerospace Society DGLR e.V. initiated in April 2001 a contest under the patronage of Mr. Joerg Feustel-Buechl, the Director of Manned Spaceflight and Microgravity, European Space Agency (ESA). Because the definition and design of living space is the content of architecture the approach was to gather new ideas from young architects in cooperation with space experts. This contest was directed at students of architecture and the task set was to design a hotel for the earth orbit and to accommodate 220 guests. The contest got the name "Early Bird - Visions of a Space Hotel". The results and models of the student's work were shown in an exhibition in Hamburg/Germany, which was open to the public from September 19th till October 20th 2001. During the summer term of 2001 seventeen designs were completed. Having specialists, as volunteers, in the field of space in charge meant that it could be ensured that the designs reflected a certain possibility of being able to be realized. Within this interdisciplinary project both parties learned from each other. The 17 different designs were focused on the expectations and needs of a future space tourist. The design are for sure not feasible today, but the designs are in that sense realistic that they could be built in future. This paper will present the overview of the 17 designs as visions of a future space hotel. The designs used

  16. [Prevalence and risk factors of urinary incontinence in female workers of hotels].

    PubMed

    Fontana, L; Falconi, G; Di Martino, T; Iavicoli, I

    2007-01-01

    The International Continence Society defines urinary incontinence (UI) as "a condition in which involuntary loss of urine is a social or hygienic problem and is objectively demonstrable". There are three different jorms of UI. stress urinary incontinence, urge urinary incontinence and mixed incontinence. The aim of this study was to investigate the prevalence of UI in a group of female workers in the hotel sector. The International Consultation on Incontinence Questionnaire Urinary Incontinence short form (ICIQ-UI Short Form) was administered to all female workers and data were collected about age, body mass index, number of vaginal and Caesarean delivery. Results showed a prevalence of UI widely bigger in the plans waitress than in video display terminal workers and suggest the hypothesis that manual handling of loads representing a possible occupational risk for UI.

  17. Space-Hotel Early Bird - An Educational and Public Outreach Approach

    NASA Astrophysics Data System (ADS)

    Amekrane, R.; Holze, C.

    2002-01-01

    In April 2001 the German Aerospace Society DGLR e.V. in cooperation with the Technical University of Darmstadt, Germany initiated an interdisciplinary students contest, under the patronage of Mr. Joerg Feustel-Buechl, the Director of Manned Spaceflight and Microgravity, European Space Agency (ESA), for the summer term 2001. It was directed to graduated architecture students, who had to conceive and design a space-hotel with specific technical, economical and social requirements. The to be developed Space Hotel for a low earth orbit has to accommodate 220 guests. It was of utmost importance that this contest becomes an integral part of the student's tuition and that professors of the different academic and industrial institutions supported the project idea. During the summer term 2001 about fifty students occupied themselves with the topic, "design of an innovative space-hotel". The overall challenge was to create rooms used under microgravity environment, which means to overcome existing definitions and to find a new definition of living space. Because none of the students were able to experience such a room under microgravity they were forced to use the power of their imagination capability. The students attended moreover a number of lectures on different technical subjects focusing on space and went on several space-related excursions. Having specialists, as volunteers, in the field of space in charge meant that it could be ensured that the designs reflected a certain possibility of being able to be realized. Within the summer term seventeen major designs developed from the conceptual status to high sophisticated concepts and later on also to respective models. A competition combined with a public exhibition, that took place within the Annual German Aeronautics and Astronautics Congress, and intense media relations finalized this project. The project idea of "Early Bird - Visions of a Space Hotel" which was developed within six month is a remarkable example, how

  18. The Relationship between Musculoskeletal Symptoms and Work-related Risk Factors in Hotel Workers

    PubMed Central

    2013-01-01

    Objectives To identify work-related musculoskeletal symptoms and any associated work-related risk factors, focusing on structural labor factors among hotel workers. Methods A total of 1,016 hotel workers (620 men and 396 women) were analyzed. The questionnaire surveyed participants’ socio-demographics, health-related behaviors, job-related factors, and work-related musculoskeletal symptoms. Work-related musculoskeletal symptoms were assessed using the Nordic musculoskeletal questionnaire. All analyses were stratified by gender, and multiple logistic regression modeling was used to determine associations between work-related musculoskeletal symptoms and work-related risk factors. Results The risk of developing work-related musculoskeletal symptoms was 1.9 times higher among male workers in the kitchen department than males in the room department (OR = 1.92, 95% CI = 1.03-3.79), and 2.5 times higher among male workers with lower sleep satisfaction than those with higher sleep satisfaction (OR = 2.52, 95% CI = 1.57-4.04). All of the aforementioned cases demonstrated a statistically significant association with work-related musculoskeletal symptoms. Moreover, the risk of developing work-related musculoskeletal symptoms was 3.3 times higher among female workers aged between 30 and 34 than those aged 24 or younger (OR = 3.32, 95% CI = 1.56-7.04); 0.3 times higher among females in the back office department than those in the room department (OR = 0.34, 95% CI = 0.12-0.91); 1.6 times higher among females on shift schedules than those who were not (OR = 1.60, 95% CI = 1.02-2.59); 1.8 times higher among females who performed more intensive work than those who performed less intensive work (OR = 1.88, 95% CI = 1.17-3.02), and; 2.1 times higher among females with lower sleep satisfaction than those with higher sleep satisfaction (OR = 2.17, 95% CI = 1.34-3.50). All of the aforementioned cases also displayed a statistically significant association with work

  19. Workplace Flexibility and Daily Stress Processes in Hotel Employees and their Children

    PubMed Central

    Almeida, David M.; Davis, Kelly D.

    2013-01-01

    Our research aims to understand the consequences of inadequate workplace flexibility through the lens of daily stress processes. Using a sample of hourly hotel employees with children aged 10 to 18 who participated in a daily diary study, we compared workers with low and high flexibility on stressor exposure, reactivity, and transmission. Our findings showed a consistent pattern of hourly workers with low flexibility having greater exposure to work stressors in general and to work place arguments in particular. Workers with low flexibility were also more emotional and physically reactive to work stressors. There was some evidence of stressor transmission to children when parents had low flexibility. Increasing workplace flexibility could serve as a protective factor in exposure and reactivity to stressors that are experienced in daily life. PMID:23833321

  20. Workplace Flexibility and Daily Stress Processes in Hotel Employees and their Children.

    PubMed

    Almeida, David M; Davis, Kelly D

    2011-11-01

    Our research aims to understand the consequences of inadequate workplace flexibility through the lens of daily stress processes. Using a sample of hourly hotel employees with children aged 10 to 18 who participated in a daily diary study, we compared workers with low and high flexibility on stressor exposure, reactivity, and transmission. Our findings showed a consistent pattern of hourly workers with low flexibility having greater exposure to work stressors in general and to work place arguments in particular. Workers with low flexibility were also more emotional and physically reactive to work stressors. There was some evidence of stressor transmission to children when parents had low flexibility. Increasing workplace flexibility could serve as a protective factor in exposure and reactivity to stressors that are experienced in daily life.

  1. Combined Heating and Power Using Microturbines in a Major Urban Hotel

    SciTech Connect

    Sweetser, Richard; Wagner, Timothy; Leslie, Neil; Stovall, Therese K

    2009-01-01

    This paper describes the results of a cooperative effort to install and operate a Cooling, Heating and Power (CHP) System at a major hotel in San Francisco, CA. The packaged CHP System integrated four microturbines, a double-effect absorption chiller, two fuel gas boosters, and the control hardware and software to ensure that the system operated predictably, reliably, and safely. The chiller was directly energized by the recycled hot exhaust from the microturbines, and could be configured to provide either chilled or hot water. As installed, the system was capable of providing up to 227 kW of net electrical power and 142 Refrigeration Tons (RT) of chilled water at a 59oF (15oC) ambient temperature. For the year, the CHP efficiency was 54 percent. Significant lessons learned from this test and verification project are discussed as well as measured performance and economic considerations.

  2. Development of desiccant based air conditioning for hotels and motels. Final report, phase 1

    SciTech Connect

    Banks, N.J.

    1994-10-01

    This report contains final reports from two phases of field tests: Phase I at the Marriott Courtyard in West Palm Beach, completed in October 1991, and Phase II at the Walt Disney World Swan Hotel in Orlando, completed in August 1993. The goal was to measure the performance and reliability of the desiccant units. The successfull program proved the value of the gas-fired desiccant technology to the hospitality industry. The desiccant units reduced moisture by 15 to 20% relative humidity. Measurements of temperature, humidity, and wallboard moisture content showed a dramatic reduction in the humidity levels experienced prior to installation of the units and in the control areas without desiccants. Moisture damage was kept in check and remodelling due to it was eliminated.

  3. Assessing the Feasibility of Comprehensive Energy Efficiency Upgrades at Potawatomi Carter Casino Hotel

    SciTech Connect

    Karman, Nathan A.

    2014-03-31

    The Forest County Potawatomi Community, a federally-recognized Indian Tribe with a strong commitment to the natural environment, sought and obtained funding to investigate energy efficient improvements to its Potawatomi Carter Casino & Hotel and the adjacent Potawatomi Carter C-Store and Smoke Shop. The resulting energy studies recommended energy conservation measures that would collectively reduce energy use by more than 30% at the facilities and would save approximately $200,000 per year in energy costs. Consistent with its commitment to the natural environment, and to advance its goal of energy independence using Carbon free or Carbon neutral renewable resources, the Community has already begun implementing certain measures and continues to seek funding sources necessary to implement the remaining measures.

  4. Thermal disinfection of hotels, hospitals, and athletic venues hot water distribution systems contaminated by Legionella species.

    PubMed

    Mouchtouri, Varvara; Velonakis, Emmanuel; Hadjichristodoulou, Christos

    2007-11-01

    Legionella spp. (> or = 500 cfu liter(-1)) were detected in 92 of 497 water distribution systems (WDS) examined. Thermal disinfection was applied at 33 WDS. After the first and second application of the disinfection procedure, 15 (45.4%) and 3 (9%) positive for remedial actions WDS were found, respectively. Legionella pneumophila was more resistant to thermal disinfection than Legionella non-pneumophila spp. (relative risk [RR]=5.4, 95% confidence intervals [CI]=1-35). WDS of hotels with oil heater were more easily disinfected than those with electrical or solar heater (RR=0.4 95% CI=0.2-0.8). Thermal disinfection seems not to be efficient enough to eliminate legionellae, unless repeatedly applied and in combination with extended heat flushing, and faucets chlorine disinfection.

  5. Evidence for airborne transmission of Norwalk-like virus (NLV) in a hotel restaurant.

    PubMed

    Marks, P J; Vipond, I B; Carlisle, D; Deakin, D; Fey, R E; Caul, E O

    2000-06-01

    An outbreak of gastroenteritis followed a meal in a large hotel during which one of the diners vomited. The clinical features of the illness suggested Norwalk-like virus (NLV, small round structured virus) infection, and this was confirmed by electron microscopy and reverse transcriptase polymerase chain reaction (RT-PCR) of stool samples. Further characterization of the virus by nucleotide sequence analysis of the PCR amplicons revealed identical strains in all the affected individuals. The foods served at the meal could not be demonstrated to be the cause of the outbreak. Analysis of attack rates by dining table showed an inverse relationship with the distance from the person who vomited. No one eating in a separate restaurant reported illness. Transmission from person-to-person or direct contamination of food seems unlikely in this outbreak. However, the findings are consistent with airborne spread of NLV with infection by inhalation with subsequent ingestion of virus particles.

  6. Live from the Mars Hotel - Space Locations and the Film Industry

    NASA Astrophysics Data System (ADS)

    Sivier, D.

    Space exploration is the subject of intense media interest in a way unparalleled in any other branch of science. It is the subject of countless films and television programmes, both fact and fiction, many using original footage from space. Astronauts have broadcast live from the Moon, and TV journalists have travelled to Mir, similar to the use of exotic terrestrial locations for filming by professional film crews. Although prohibitively expensive at the moment, the next generation of spacecraft may lower launch costs to an affordable level, so that space locations become competitive against computer graphics and model work. The construction of orbital hotels will create the demand for human interest stories similar to those set in holiday locations like the south of France and Italy made just after the Second World War, at a time when mass tourism on foreign holidays was just beginning, aided by the development of large transport aircraft able to cater to the demand for mass flight.

  7. Exploring the Legionella pneumophila positivity rate in hotel water samples from Antalya, Turkey.

    PubMed

    Sepin Özen, Nevgün; Tuğlu Ataman, Şenay; Emek, Mestan

    2017-03-29

    The genus Legionella is a fastidious Gram-negative bacteria widely distributed in natural waters and man made water supply systems. Legionella pneumophila is the aetiological agent of approximately 90% of reported Legionellosis cases, and serogroup 1 is the most frequent cause of infections. Legionnaires' disease is often associated with travel and continues to be a public health concern at present. The correct water management quality practices and rapid methods for analyzing Legionella species in environmental water is a key point for the prevention of Legionnaires' disease outbreaks. This study aimed to evaluate the positivity rates and serotyping of Legionella species from water samples in the region of Antalya, Turkey, which is an important tourism center. During January-December 2010, a total of 1403 samples of water that were collected from various hotels (n = 56) located in Antalya were investigated for Legionella pneumophila. All samples were screened for L. pneumophila by culture method according to "ISO 11731-2" criteria. The culture positive Legionella strains were serologically identified by latex agglutination test. A total of 142 Legionella pneumophila isolates were recovered from 21 (37.5%) of 56 hotels. The total frequency of L. pneumophila isolation from water samples was found as 10.1%. Serological typing of 142 Legionella isolates by latex agglutination test revealed that strains belonging to L. pneumophila serogroups 2-14 predominated in the examined samples (85%), while strains of L. pneumophila serogroup 1 were less numerous (15%). According to our knowledge, our study with the greatest number of water samples from Turkey demonstrates that L. pneumophila serogroups 2-14 is the most common isolate. Rapid isolation of L. pneumophila from environmental water samples is essential for the investigation of travel related outbreaks and the possible resources. Further studies are needed to have epidemiological data and to determine the types of L

  8. Model-based condition monitoring of PEM fuel cell using Hotelling T 2 control limit

    NASA Astrophysics Data System (ADS)

    Xue, X.; Tang, J.; Sammes, N.; Ding, Y.

    Although a variety of design and control strategies have been proposed to improve the performance of polymer electrolyte membrane (PEM) fuel cell systems, temporary faults in such systems still might occur during operations due to the complexity of the physical process and the functional limitations of some components. The development of an effective condition monitoring system that can detect these faults in a timely manner is complicated by the operating condition variation, the significant variability/uncertainty of the fuel cell system, and the measurement noise. In this research, we propose a model-based condition monitoring scheme that employs the Hotelling T 2 statistical analysis for fault detection of PEM fuel cells. Under a given operating condition, the instantaneous load current, the temperature and fuel/gas source pressures of the fuel cell are measured. These measurements are then fed into a lumped parameter dynamic fuel cell model for the establishment of the baseline under the same operating condition for comparison. The fuel cell operation is simulated under statistical sampling of parametric uncertainties with specified statistics (mean and variance) that account for the system variability/uncertainty and measurement noise. This yields a group of output voltages (under the same operating condition but with uncertainties) as the baseline. Fault detection is facilitated by comparing the real-time measurement of the fuel cell output voltage with the baseline voltages by employing the Hotelling T 2 statistical analysis. The baseline voltages are used to evaluate the output T 2 statistics under normal operating condition. Then, with a given confidence level the upper control limit can be specified. Fault condition will be declared if the T 2 statistics of real-time voltage measurement exceeds the upper control limit. This model-based robust condition monitoring scheme can deal with the operating condition variation, various uncertainties in a fuel cell

  9. A food-borne outbreak of cryptosporidiosis among guests and staff at a hotel restaurant in Stockholm county, Sweden, September 2008.

    PubMed

    Insulander, M; de Jong, B; Svenungsson, B

    2008-12-18

    In September 2008, 21 cases of cryptosporidiosis occurred among guests and staff at a wedding reception in a hotel restaurant in Stockholm county, Sweden. The most probable source of the outbreak was bearnaise sauce containing chopped fresh parsley.

  10. Identification of the infectious source of an unusual outbreak of histoplasmosis, in a hotel in Acapulco, state of Guerrero, Mexico.

    PubMed

    Taylor, Maria Lucia; Ruíz-Palacios, Guillermo M; del Rocío Reyes-Montes, María; Rodríguez-Arellanes, Gabriela; Carreto-Binaghi, Laura E; Duarte-Escalante, Esperanza; Hernández-Ramírez, Aurora; Pérez, Armando; Suárez-Alvarez, Roberto O; Roldán-Aragón, Yuri A; Romero-Martínez, Rafael; Sahaza-Cardona, Jorge H; Sifuentes-Osornio, José; Soto-Ramírez, Luis E; Peña-Sandoval, Gabriela R

    2005-09-01

    Three isolates of Histoplasma capsulatum were identified from mice lung, liver, and spleen inoculated with soil samples of the X hotel's ornamental potted plants that had been fertilized with organic material known as compost. The presence of H. capsulatum in the original compost was detected using the dot-enzyme-linked immunosorbent assay. Nested-PCR, using a specific protein Hcp100 coding gene sequence, confirmed the fungal identification associated with an unusual histoplasmosis outbreak in Acapulco. Although, diversity between the H. capsulatum isolate from the hotel and some clinical isolates from Guerrero (positive controls) was observed using random amplification of polymorphic DNA based-PCR, sequence analyses of H-anti and ole fragment genes revealed a high homology (92-99%) between them.

  11. [High time for a total ban on smoking in the hotel, restaurant and catering industry: the arguments are mounting].

    PubMed

    Hassink, R J; Franke, L J A

    2007-02-24

    Active and passive smoking are well-known causes of disease, including respiratory and cardiovascular disease and cancer. In 2004 the Dutch government introduced new legislation to regulate smoking in the workplace. However, smoking is still allowed in hotels, bars and restaurants, despite the fact that two-thirds of the Dutch population support a total ban on smoking in public places. Several other European countries and American states have banned smoking in public places. Studies performed in these regions show that the new smoking regulations have had no negative economic effects. Moreover, various studies have shown that smoking bans have a positive impact on public health, even in the short-term, including a significant decrease in respiratory and cardiovascular disease. There is therefore no reason to continue to exclude hotels, bars and restaurants from the smoking ban in all public places in The Netherlands.

  12. Genetic hotels for the standard genetic code: evolutionary analysis based upon novel three-dimensional algebraic models.

    PubMed

    José, Marco V; Morgado, Eberto R; Govezensky, Tzipe

    2011-07-01

    Herein, we rigorously develop novel 3-dimensional algebraic models called Genetic Hotels of the Standard Genetic Code (SGC). We start by considering the primeval RNA genetic code which consists of the 16 codons of type RNY (purine-any base-pyrimidine). Using simple algebraic operations, we show how the RNA code could have evolved toward the current SGC via two different intermediate evolutionary stages called Extended RNA code type I and II. By rotations or translations of the subset RNY, we arrive at the SGC via the former (type I) or via the latter (type II), respectively. Biologically, the Extended RNA code type I, consists of all codons of the type RNY plus codons obtained by considering the RNA code but in the second (NYR type) and third (YRN type) reading frames. The Extended RNA code type II, comprises all codons of the type RNY plus codons that arise from transversions of the RNA code in the first (YNY type) and third (RNR) nucleotide bases. Since the dimensions of remarkable subsets of the Genetic Hotels are not necessarily integer numbers, we also introduce the concept of algebraic fractal dimension. A general decoding function which maps each codon to its corresponding amino acid or the stop signals is also derived. The Phenotypic Hotel of amino acids is also illustrated. The proposed evolutionary paths are discussed in terms of the existing theories of the evolution of the SGC. The adoption of 3-dimensional models of the Genetic and Phenotypic Hotels will facilitate the understanding of the biological properties of the SGC.

  13. Sanitary status and incidence of methicillin-resistant Staphylococcus aureus and Clostridium difficile within Canadian hotel rooms.

    PubMed

    Xu, Changyun; Weese, Scott J; Namvar, Azadeh; Warriner, Keith

    2015-04-01

    The study described in this article aimed at establishing a baseline assessment of the sanitary status of ice and guest rooms within Canadian hotels. Collectively, 54 hotel rooms belonging to six different national chains were sampled. High-contact surfaces (comforter, alarm clock, bedside lamp, TV remote, bathroom countertop, faucet, and toilet seat) were sampled using adenosine triphosphate (ATP) swabs and replicate organism detection and counting plates. ATP swab readings ranged from 2.12 to 4.42 log relative light units. Coliforms were recovered from 36% of surfaces with high prevalence being recovered from the comforter, TV remote, bathroom countertop, faucet, and toilet seat. Oxacillin-resistant bacteria were recovered from 19% of surfaces with 46% of isolates confirmed as methicillin-resistant Staphylococcus aureus. Two toxigenic Clostridium difficile isolates were recovered in the course of the study. Collectively, 24% of the ice samples harbored coliforms with a single sample testing positive for E. coli. The authors' study demonstrates that hotel rooms represent a potential source of community-acquired infections and the need for enhanced sanitation practices.

  14. Indoor and outdoor carbonyl compounds in the hotel ballrooms in Guangzhou, China

    NASA Astrophysics Data System (ADS)

    Feng, Yanli; Wen, Sheng; Wang, Xinming; Sheng, Guoying; He, Qiusheng; Tang, Jianhui; Fu, Jiamo

    Twenty-one carbonyl compounds were measured simultaneously at four hotel ballrooms in urban Guangzhou during the autumn, 2002. In each ballroom, measurements were carried out in business hours in the evening (20:30-24:00) on 7 consecutive days without any disturbance of the ballroom's normal operation. Nineteen out of the 21 target carbonyl compounds were identified in indoor and outdoor air. In the outdoor environment, formaldehyde was the most abundant carbonyl, followed by acetaldehyde, and there existed a strong correlation between formaldehyde and acetaldehyde. In the indoor air, however, acetaldehyde was the most abundant carbonyl, its concentrations seemed to be affected significantly by smoking. The indoor concentrations of carbonyls were found higher than their outdoor counterparts with only a few exceptions. Further studies concerning the indoor/outdoor ratios and mutual correlation of the carbonyls indicated that apart from direct emission from indoor materials and infiltration of outdoor air, other anthropogenic sources, e.g. tobacco smoke, also significantly contributed to carbonyl compounds. The possible sources of some high molecular weight carbonyls, e.g. nonanaldehyde, were also discussed briefly. Preliminary estimate of the exposures and risks due to carbonyls in the ballrooms was made, which indicated that long-term exposure in such places might cause increased chance of developing cancers.

  15. Household, hotel and market waste audits for composting in Vietnam and Laos.

    PubMed

    Byer, Philip H; Hoang, Chi Phuong; Nguyen, Thi Thuc Thuy; Chopra, Sangeeta; Maclaren, Virginia; Haight, Murray

    2006-10-01

    In Da Nang and Ha Long, Vietnam and in Vientiane, Laos, there was interest by local authorities in separating and composting waste in order to reduce environmental and health problems at the local landfills and to produce a soil conditioner for local agricultural use. To assist in the planning of composting projects, three studies were carried out to estimate waste quantities and composition. 1. A 9-day audit of waste from 45 vendors in a market in Vientiane, the capital of Laos. The total quantity of waste and the quantity in each of nine categories were estimated for each of six different types of vendors. 2. A 7-day audit of waste disposed by three hotels in the tourist area of Ha Long, Vietnam. Waste quantities were estimated in total, on a per guest basis, and in three main categories: compostables, recyclables and miscellaneous. 3. A 7-day audit of waste collected from 74 households in Da Nang, the fourth largest city in Vietnam. Waste from each household was separated into compostable and non-compostable waste. Over 60% of each waste source comprised compostable waste and this was considered significant enough to warrant further planning of composting operations.

  16. Image-domain sampling properties of the Hotelling Observer in CT using filtered back-projection

    NASA Astrophysics Data System (ADS)

    Sanchez, Adrian A.; Sidky, Emil Y.; Pan, Xiaochuan

    2015-03-01

    The Hotelling Observer (HO),1 along with its channelized variants,2 has been proposed for image quality evaluation in x-ray CT.3,4 In this work, we investigate HO performance for a detection task in parallel-beam FBP as a function of two image-domain sampling parameters, namely pixel size and field-of-view. These two parameters are of central importance in adapting HO methods to use in CT, since the large number of pixels in a single image makes direct computation of HO performance for a full image infeasible in most cases. Reduction of the number of image pixels and/or restriction of the image to a region-of-interest (ROI) has the potential to make direct computation of HO statistics feasible in CT, provided that the signal and noise properties lead to redundant information in some regions of the image. For small signals, we hypothesize that reduction of image pixel size and enlargement of the image field-of-view are approximately equivalent means of gaining additional information relevant to a detection task. The rationale for this hypothesis is that the backprojection operation in FBP introduces long range correlations so that, for small signals, the reconstructed signal outside of a small ROI is not linearly independent of the signal within the ROI. In this work, we perform a preliminary investigation of this hypothesis by sweeping these two sampling parameters and computing HO performance for a signal detection task.

  17. Hydrologic data, 1974-77, Stovepipe Wells Hotel area, Death Valley National Monument, Inyo County, California

    USGS Publications Warehouse

    Lamb, Charles Edwin; Downing, D.J.

    1979-01-01

    Ground-water levels in most wells did not change significantly from 1974 to 1977 in the Stovepipe Wells Hotel area, California. The average water-level decline was less than 0.10 foot between August 1974 and August 1977 in 10 observation wells. Water-level contours show a depression centered on the two pumping wells, but this depression existed before the National Park Service started pumping its well. The chemical quality of the ground water is poor. Dissolved-solids concentrations in water samples ranged from 2,730 to 6,490 milligrams per liter. Analyses of water samples from two wells showed large changes in some constituents from 1976 to 1977. Streamflow in Salt Creek has been monitored since February 1974. Base flow is seasonal, being 0.10 to 0.20 cubic foot per second during the summer and as much as three times that amount during the winter. Two chemical analyses of water from Salt Creek, representing summer and winter flow conditions, show large differences for many constituents. (Woodard-USGS)

  18. A Waterborne Gastroenteritis Outbreak Caused by Norovirus GII.17 in a Hotel, Hebei, China, December 2014.

    PubMed

    Qin, Meng; Dong, Xiao-Gen; Jing, Yan-Yan; Wei, Xiu-Xia; Wang, Zhao-E; Feng, Hui-Ru; Yu, Hong; Li, Jin-Song; Li, Jie

    2016-09-01

    Norovirus (NoV) is responsible for an estimated 90 % of all epidemic nonbacterial outbreaks of gastroenteritis worldwide. Waterborne outbreaks of NoV are commonly reported. A novel GII.17 NoV strain emerged as a major cause of gastroenteritis outbreaks in China during the winter of 2014/2015. During this time, an outbreak of gastroenteritis occurred at a hotel in a ski park in Hebei Province, China. Epidemiological investigations indicated that one water well, which had only recently been in use, was the probable source. GII.17 NoV was detected by real-time reverse-transcription polymerase chain reaction from samples taken from cases, from concentrated water samples from water well, and from the nearby sewage settling tank. Nucleotide sequences of NoV extracted from clinical and water specimens were genetically identical and had 99 % homology with Beijing/CHN/2015. All epidemiological data indicated that GII.17 NoV was responsible for this outbreak. This is the first reported laboratory-confirmed waterborne outbreak caused by GII.17 NoV genotype in China. Strengthening management of well drinking water and systematica monitoring of NoV is essential for preventing future outbreaks.

  19. SKE/BKE task-based methodology for calculating Hotelling observer SNR in mammography

    NASA Astrophysics Data System (ADS)

    Liu, Haimo; Kyprianou, Iacovos S.; Badano, Aldo; Myers, Kyle J.; Jennings, Robert J.; Park, Subok; Kaczmarek, Richard V.; Chakrabarti, Kish

    2009-02-01

    A common method for evaluating projection mammography is Contrast-Detail (CD) curves derived from the CD phantom for Mammography (CDMAM). The CD curves are derived either by human observers, or by automated readings. Both methods have drawbacks which limit their reliability. The human based reading is significantly affected by reader variability, reduced precision and bias. On the other hand, the automated methods suffer from limited statistics. The purpose of this paper is to develop a simple and reliable methodology for the evaluation of mammographic imaging systems using the Signal Known Exactly/Background Known Exactly (SKE/BKE) detection task for signals relevant to mammography. In this paper, we used the spatial definition of the ideal, linear (Hotelling) observer to calculate the task-specific SNR for mammography and discussed the results. The noise covariance matrix as well as the detector response H matrix of the imaging system were estimated and used to calculate the SNRSKEBKE for the simulated discs of the CDMAM. The SNR as a function of exposure, disc diameter and thickness were calculated.

  20. Individual treatment of hotel and restaurant waste water in rural areas.

    PubMed

    Van Hulle, S W H; Ghyselbrecht, N; Vermeiren, T J L; Depuydt, V; Boeckaert, C

    2012-01-01

    About 25 hotels, restaurants and pubs in the rural community Heuvelland are situated in the area designated for individual water treatment. In order to meet the legislation by the end of 2015, each business needs to install an individual waste water treatment system (IWTS). To study this situation, three catering businesses were selected for further research. The aim of the study was to quantify the effluent quality and to assess IWTS performance for these catering businesses. First of all, the influence of discharging untreated waste water on the receiving surface water was examined. The results showed a decrease in water quality after the discharge point at every business. With the collected data, simulations with the software WEST were performed. With this software two types of IWTSs with different (buffer) volumes were modelled and tested for each catering business. The first type is a completely mixed activated sludge reactor and the second type is a submerged aerobic fixed-bed reactor. The results of these simulations demonstrate that purification with an IWTS is possible if the capacity is large enough and if an adequate buffer volume is installed and if regular maintenance is performed.

  1. Academic medicine amenities unit: developing a model to integrate academic medical care with luxury hotel services.

    PubMed

    Kennedy, David W; Kagan, Sarah H; Abramson, Kelly Brennen; Boberick, Cheryl; Kaiser, Larry R

    2009-02-01

    The interface between established values of academic medicine and the trend toward inpatient amenities units requires close examination. Opinions of such units can be polarized, reflecting traditional reservations about the ethical dilemma of offering exclusive services only to an elite patient group. An amenities unit was developed at the University of Pennsylvania Health System in 2007, using an approach that integrated academic medicine values with the benefits of philanthropy and service excellence to make amenities unit services available to all patients. Given inherent internal political concerns, a broadly based steering committee of academic and hospital leadership was developed. An academically appropriate model was conceived, anchored by four principles: (1) integration of academic values, (2) interdisciplinary senior leadership, (3) service excellence, and (4) recalibrated occupancy expectations based on multiple revenue streams. Foremost is ensuring the same health care is afforded all patients throughout the hospital, thereby overcoming ethical challenges and optimizing teaching experiences. Service excellence frames the service ethic for all staff, and this, in addition to luxury hotel-style amenities, differentiates the style and feel of the unit from others in the hospital. Recalibrated occupancy creates program viability given revenue streams redefined to encompass gifts and patient revenue, including both reimbursement and self-pay. The medical-surgical amenities patient-care unit has enjoyed a successful first year and a growing stream of returning patients and admitting physicians. Implications for other academic medical centers include opportunities to extrapolate service excellence throughout the hospital and to cultivate philanthropy to benefit services throughout the medical center.

  2. The use of kernel local Fisher discriminant analysis for the channelization of the Hotelling model observer

    NASA Astrophysics Data System (ADS)

    Wen, Gezheng; Markey, Mia K.

    2015-03-01

    It is resource-intensive to conduct human studies for task-based assessment of medical image quality and system optimization. Thus, numerical model observers have been developed as a surrogate for human observers. The Hotelling observer (HO) is the optimal linear observer for signal-detection tasks, but the high dimensionality of imaging data results in a heavy computational burden. Channelization is often used to approximate the HO through a dimensionality reduction step, but how to produce channelized images without losing significant image information remains a key challenge. Kernel local Fisher discriminant analysis (KLFDA) uses kernel techniques to perform supervised dimensionality reduction, which finds an embedding transformation that maximizes betweenclass separability and preserves within-class local structure in the low-dimensional manifold. It is powerful for classification tasks, especially when the distribution of a class is multimodal. Such multimodality could be observed in many practical clinical tasks. For example, primary and metastatic lesions may both appear in medical imaging studies, but the distributions of their typical characteristics (e.g., size) may be very different. In this study, we propose to use KLFDA as a novel channelization method. The dimension of the embedded manifold (i.e., the result of KLFDA) is a counterpart to the number of channels in the state-of-art linear channelization. We present a simulation study to demonstrate the potential usefulness of KLFDA for building the channelized HOs (CHOs) and generating reliable decision statistics for clinical tasks. We show that the performance of the CHO with KLFDA channels is comparable to that of the benchmark CHOs.

  3. A Channelized Hotelling Observer Study of Lesion Detection in SPECT MAP Reconstruction Using Anatomical Priors

    PubMed Central

    Kulkarni, S.; Khurd, P.; Hsiao, I.; Zhou, L.; Gindi, G.

    2010-01-01

    In emission tomography, anatomical side information, in the form of organ and lesion boundaries, derived from intra-patient coregistered CT or MR scans can be incorporated into the reconstruction. Our interest is in exploring the efficacy of such side information for lesion detectability. To assess detectability we used the SNR of a channelized Hotelling observer and a signal-known exactly/background known exactly detection task. In simulation studies we incorporated anatomical side information into a SPECT MAP (maximum a posteriori) reconstruction by smoothing within but not across organ or lesion boundaries. A non-anatomical prior was applied by uniform smoothing across the entire image. We investigated whether the use of anatomical priors with organ boundaries alone or with perfect lesion boundaries alone would change lesion detectability relative to the case of a prior with no anatomical information. Furthermore, we investigated whether any such detectability changes for the organ-boundary case would be a function of the distance of the lesion to the organ boundary. We also investigated whether any detectability changes for the lesion-boundary case would be a function of the degree of proximity, i.e. a difference in the radius of the true functional lesion and the radius of the anatomical lesion boundary. Our results showed almost no detectability difference with vs without organ boundaries at any lesion-to-organ boundary distance. Our results also showed no difference in lesion detectability with and without lesion boundaries, and no variation of lesion detectability with degree of proximity. PMID:17664562

  4. Occurrence and parameters of frequency of Legionella in warm water systems of hospitals and hotels in Lower Saxony.

    PubMed

    Habicht, W; Müller, H E

    1988-03-01

    A total of 1241 water samples was investigated from 103 hospitals and 62 hotels in Lower Saxony 1985-87. 331 of 949 samples from hospitals and 26 of 292 samples from hotels were Legionella positive. All together 70% of the hospitals and 18% of the hotels investigated were Legionella positive, and 836 strains of Legionella were isolated (Table 1). As they could be diagnosed they belong to L. pneumophila SG1 306 strains, SG2 36 strains, SG3 127 strains, SG4 45 strain, SG5 29 strain, SG6 106 strains, SG9 13 strains and SG10 13 strains. Further 134 strains belonging to L. pneumophila but not to SG1-SG12 show cross reactions with serogroups 5, 8, and 10. Finally, 16 strains belong to L. dumoffii and 1 strain to L. anisa (Table 2). The following parameters of water samples were studied, too: temperature, pH value, conductivity, concentration of iron, of organic matter, of other bacteria, occurrence of amoebas, and the materials of water plumbing systems. Most samples contained concentrations of Legionella in the range of 10(1)-10(3) CFU/ml, highest concentrations were 10(5) CFU/ml (Fig. 1). Most frequently, Legionella were isolated within the range of temperature of 35-45 degrees C. However, a few of the water samples were positive for Legionella even up to 66 degrees C (Fig. 3). The conductivity has no and the pH value (Fig. 2) has only little influence on the occurrence of Legionella. There is a positive correlation between concentration of iron and frequency of Legionella (Fig. 4). Also organic matter (Fig. 6) and amoebas (Table 3) seem to enhance the occurrence of Legionella. Plumbing systems consisting of copper showed an inhibitory effect on Legionella during the first five years, whereas no effect could be detected in older systems (Fig. 5).

  5. Auroras Now! - Auroral nowcasting service for Hotels in Finnish Lapland and its performance during winter 2003-2004

    NASA Astrophysics Data System (ADS)

    Kauristie, K.; Mälkki, A.; Pulkkinen, A.; Nevanlinna, H.; Ketola, A.; Tulkki, V.; Raita, T.; Blanco, A.

    2004-12-01

    European Space Agency is currently supporting 17 Service Development Activities (SDA) within its Space Weather Pilot Project. Auroras Now!, one of the SDAs, has been operated during November 2003 - March 2004 as its pilot season. The service includes a public part freely accessible in Internet (http://aurora.fmi.fi) and a private part visible only to the customers of two hotels in the Finnish Lapland through the hotels' internal TV-systems. The nowcasting system is based on the magnetic recordings of two geophysical observatories, Sodankylä (SOD, MLAT ~64 N) and Nurmijärvi (NUR, MLAT ~57 N). The probability of auroral occurrence is continuously characterised with an empirically determined three-level scale. The index is updated once per hour and based on the magnetic field variations recorded at the observatories. During dark hours the near-real time auroral images acquired at SOD are displayed. The hotel service also includes cloudiness predictions for the coming night. During the pilot season the reliability of the three-level magnetic alarm system was weekly evaluated by comparing its prediction with auroral observations by the nearby all-sky camera. Successful hits and failures were scored according to predetermined rules. The highest credit points when it managed to spot auroras in a timely manner and predict their brightness correctly. Maximum penalty points were given when the alarm missed clear bright auroras lasting for more than one hour. In this presentation we analyse the results of the evaluation, present some ideas to further sharpen the procedure, and discuss more generally the correlation between local auroral and magnetic activity.

  6. Health-seeking behavior and social networks of the aged living in single-room occupancy hotels.

    PubMed

    Cohen, C I; Sokolovsky, J

    1979-06-01

    The elderly who reside in single-room occupancy (SRO) hotels often have been depicted as "isolates," lacking the interest or ability to engage primary or secondary support systems. This characterization has not enhanced understanding of how the SRO aged are able to survive in the community. With the use of network analysis techniques, this study demonstrates the inaccuracy of the assertion that these old persons lack significant social support. The data pointed to differences in network size, complexity, intensity, connectedness, and directionality in relation to varying degrees of physical and psychiatric health.

  7. Special report. Hospitals that are becoming 'hotel friendly' to guests ... and the role played by security officers.

    PubMed

    1996-01-01

    Faced with increasing competition, hospitals in New York City are developing programs to become more user friendly and, like hotels, to treat patients more as "guests" than as "customers." These programs, which have particular applications for security personnel, are also seeking to improve communications and relationships among the hospital's medical staff and other employees. In this report, we'll describe some of these efforts in which hospitals are turning to hoteliers, consultants, and others for advice in the area of customer service, and the role seen for hospital security.

  8. A model project in community mental health: Consultation to an urban welfare center serving a single-room occupancy hotel.

    PubMed

    Levitt, L I; Brownlee, W H; Lewars, M H

    1968-12-01

    A continuing consultative relationship between a general hospital department of psychiatry and an urban welfare center serving the residents of a privately owned hotel is described-the relationship is based on biweekly seminars. Individual case study is the method of training, and an activity program the vehicle for development of indigenous resident leadership. Problems in residents' relationship to their community, worker-resident relationships, resistances of residents, anticipating both workers and residents' readiness to assume responsibility, and defining the role of consultant were confronted. The project demonstrates the effectiveness of the technique, pointing up the need for refinement of the process and the development of tools for measurement.

  9. Analysis of Sleep Parameters in Patients with Obstructive Sleep Apnea Studied in a Hospital vs. a Hotel-Based Sleep Center

    PubMed Central

    Hutchison, Kimberly N.; Song, Yanna; Wang, Lily; Malow, Beth A.

    2008-01-01

    Background: Polysomnography is associated with changes in sleep architecture called the first-night effect. This effect is believed to result from sleeping in an unusual environment and the technical equipment used to study sleep. Sleep experts hope to decrease this variable by providing a more familiar, comfortable atmosphere for sleep testing through hotel-based sleep centers. In this study, we compared the sleep parameters of patients studied in our hotel-based and hospital-based sleep laboratories. Methods: We retrospectively reviewed polysomnograms completed in our hotel-based and hospital-based sleep laboratories from August 2003 to July 2005. All patients were undergoing evaluation for obstructive sleep apnea. Hospital-based patients were matched for age and apnea-hypopnea index with hotel-based patients. We compared the sleep architecture changes associated with the first-night effect in the two groups. The associated conditions and symptoms listed on the polysomnography referral forms are also compared. Results: No significant differences were detected between the two groups in sleep onset latency, sleep efficiency, REM sleep latency, total amount of slow wave sleep (NREM stages 3 and 4), arousal index, and total stage 1 sleep. Conclusions: This pilot study failed to show a difference in sleep parameters associated with the first-night effect in patients undergoing sleep studies in our hotel and hospital-based sleep laboratories. Future studies need to compare the first-night effect in different sleep disorders, preferably in multi-night recordings. Citation: Hutchison KN; Song Y; Wang L; Malow BA. Analysis of sleep parameters in patients with obstructive sleep apnea studied in a hospital vs. A hotel-based sleep center. J Clin Sleep Med 2008;4(2):119–122. PMID:18468309

  10. Microbiological levels of randomly selected food contact surfaces in hotels located in Spain during 2007-2009.

    PubMed

    Doménech-Sánchez, Antonio; Laso, Elena; Pérez, María José; Berrocal, Clara Isabel

    2011-09-01

    The aim of this study was to survey the microbial levels of food contact surfaces in hotels. Microbiological levels of 4611 surfaces (chopping machines, kitchenware, knives, worktops, and cutting boards) from 280 different facilities in Spain were determined in a 3-year period. The contact-plate technique was used throughout the survey. Overall, the mean of the log of total aerobic count cm(-2) was 0.62, better than those reported for child-care and assisted living facilities. Significant differences were detected among different types of surfaces, time of sampling, season, and year. The majority (74%) of food contact surfaces sampled in Spanish hotels was within the recommended standard of <1.3 log CFU cm(-2), and differences depend on several factors. Our results set a representative picture of the actual situation in our resorts and establish the basis for the development of educational programs to improve food handlers' knowledge of foodborne diseases and their transmission via food contact surfaces.

  11. Evaluation of increases in dissolved solids in ground water, Stovepipe Wells Hotel, Death Valley National Monument, California

    USGS Publications Warehouse

    Buono, Anthony; Packard, E.M.

    1982-01-01

    Increases in dissolved solids have been monitored in two observation wells near Stovepipe Wells Hotel, Death Valley National Monument, California. One of the hotel 's supply wells delivers water to a reverse-osmosis treatment plant that produces the area 's potable water supply. Should water with increased dissolved solids reach the supply well, the costs of production of potable water will increase. The reverse-osmosis plant supply well is located about 0.4 mile south of one of the wells where increases have been monitored, and 0.8 mile southwest of the well where the most significant increases have been monitored. The direction of local ground-water movement is eastward, which reduces the probability of the supply well being affected. Honey mesquite, a phreatophyte located about 1.5 miles downgradient from the well where the most significant increases have been monitored, might be adversely affected should water with increased dissolved solids extend that far. Available data and data collected during this investigation do not indicate the source of the dissolved-solids increases. Continued ground-water-quality monitoring of existing wells and the installation of additional wells for water-quality monitoring would be necessary before the area affected by the increases, and the source and direction of movement of the water with increased dissolved solids, can be determined. (USGS)

  12. Task specific evaluation of clinical full field digital mammography systems using the Fourier definition of the Hotelling observer SNR

    NASA Astrophysics Data System (ADS)

    Liu, Haimo; Badano, Aldo; Benevides, Luis; Chakrabarti, Kish; Kaczmarek, Richard V.; Kyprianou, Iacovos S.

    2010-04-01

    Pixel Signal to Noise Ratio (SNR) is a commonly used clinical metric for evaluating mammography. However, we showed in this paper, the pixel SNR can produce misleading system detectability when image processing is utilized. We developed a simple, reliable and clinically applicable methodology to evaluate mammographic imaging systems using a task SNR that accounts for the imaging system performance in the presence of the patient. We used the Hotelling observer method in spatial frequency domain to calculate the task SNR of small disk test objects embedded in the breast tissue-equivalent series (BRTES) phantom for GE Senographe DS Full Field Digital Mammography (FFDM) system. The results were compared to the calculation of pixel SNR. We calculated the Hotelling observer SNR by estimating the generalized modulation transfer function (GMTF), generalized normalized noise power spectrum (GNNPS) and generalized noise equivalent quanta (GNEQ) in the presence of the breast phantom. The task SNR we calculated increased with the square root of the exposure as expected. Furthermore, we showed that the method is stable under image processing. The task SNR is a more reliable method for evaluating the performance of imaging systems especially under realistic clinical conditions where patient equivalent phantoms or image processing is used.

  13. A hotel-based outbreak of Salmonella enterica subsp. Enterica serovar Enteritidis (Salmonella Enteritidis) in the United Kingdom, 2006.

    PubMed

    Calvert, N; Murphy, L; Smith, A; Copeland, D

    2007-03-01

    An outbreak of food-borne Salmonella Enteritidis PT4 occurred in Cumbria, in north-west England, in the summer of 2006. Fifteen people, all with positive stool samples, met the case definition; three of these were admitted to hospital, including one patient who died. Preliminary investigations suggested a link to a meal served at a local hotel. A case control study was implemented, together with microbiological and environmental investigations. Fifteen microbiologically confirmed cases and 27 unmatched controls were included in the study, controls being randomly selected from people who had eaten at the hotel on the same day. The epidemiological evidence indicated a very strong association between infection and consumption of tiramisu made with raw shell eggs, although none were available for microbiological investigation. These results are in line with other salmonellosis outbreaks that have been associated with the use of raw shell eggs in food manufacturing and production. This paper highlights the continuing need for a greater awareness by those who work in the food industry of the health risks associated with the consumption of raw shell eggs.

  14. HIV-1 pol diversity among female bar and hotel workers in Northern Tanzania.

    PubMed

    Kiwelu, Ireen E; Novitsky, Vladimir; Kituma, Elimsaada; Margolin, Lauren; Baca, Jeannie; Manongi, Rachel; Sam, Noel; Shao, John; McLane, Mary F; Kapiga, Saidi H; Essex, M

    2014-01-01

    A national ART program was launched in Tanzania in October 2004. Due to the existence of multiple HIV-1 subtypes and recombinant viruses co-circulating in Tanzania, it is important to monitor rates of drug resistance. The present study determined the prevalence of HIV-1 drug resistance mutations among ART-naive female bar and hotel workers, a high-risk population for HIV-1 infection in Moshi, Tanzania. A partial HIV-1 pol gene was analyzed by single-genome amplification and sequencing in 45 subjects (622 pol sequences total; median number of sequences per subject, 13; IQR 5-20) in samples collected in 2005. The prevalence of HIV-1 subtypes A1, C, and D, and inter-subtype recombinant viruses, was 36%, 29%, 9% and 27%, respectively. Thirteen different recombination patterns included D/A1/D, C/A1, A1/C/A1, A1/U/A1, C/U/A1, C/A1, U/D/U, D/A1/D, A1/C, A1/C, A2/C/A2, CRF10_CD/C/CRF10_CD and CRF35_AD/A1/CRF35_AD. CRF35_AD was identified in Tanzania for the first time. All recombinant viruses in this study were unique, suggesting ongoing recombination processes among circulating HIV-1 variants. The prevalence of multiple infections in this population was 16% (n = 7). Primary HIV-1 drug resistance mutations to RT inhibitors were identified in three (7%) subjects (K65R plus Y181C; N60D; and V106M). In some subjects, polymorphisms were observed at the RT positions 41, 69, 75, 98, 101, 179, 190, and 215. Secondary mutations associated with NNRTIs were observed at the RT positions 90 (7%) and 138 (6%). In the protease gene, three subjects (7%) had M46I/L mutations. All subjects in this study had HIV-1 subtype-specific natural polymorphisms at positions 36, 69, 89 and 93 that are associated with drug resistance in HIV-1 subtype B. These results suggested that HIV-1 drug resistance mutations and natural polymorphisms existed in this population before the initiation of the national ART program. With increasing use of ARV, these results highlight the importance of drug

  15. Task-based optimization of dedicated breast CT via Hotelling observer metrics

    PubMed Central

    Sanchez, Adrian A.; Sidky, Emil Y.; Pan, Xiaochuan

    2014-01-01

    Purpose: The purpose of this work is to develop and demonstrate a set of practical metrics for CT systems optimization. These metrics, based on the Hotelling observer (HO) figure of merit, are task-based. The authors therefore take the specific example of optimizing a dedicated breast CT system, including the reconstruction algorithm, for two relevant tasks, signal detection and Rayleigh discrimination. Methods: A dedicated breast CT system is simulated using specifications in the literature from an existing prototype. The authors optimize configuration and image reconstruction algorithm parameters for two tasks: the detection of simulated microcalcifications and the discrimination of two adjacent, high-contrast signals, known as the Rayleigh discrimination task. The effects on task performance of breast diameter, signal location, image grid size, projection view number, and reconstruction filter were all investigated. Two HO metrics were evaluated: the percentage of correct decisions in a two-alternative forced choice experiment (equivalent to area under the ROC curve or AUC), and the HO efficiency, defined as the squared ratio of HO signal-to-noise ratio (SNR) in the reconstructed image to HO SNR in the projection data. Results: The ease and efficiency of the HO metric computation allows a rapid high-resolution survey of many system parameters. Optimization of a range of system parameters using the HO results in images that subjectively appear optimal for the tasks investigated. Further, the results of assessment through the HO reproduce closely many existing results in the literature regarding the impact of parameter selection on image quality. Conclusions: This study demonstrates the utility of a task-based approach to system design, evaluation, and optimization. The methodology presented is equally applicable to determining the impact of a wide range of factors, including patient parameters, system and acquisition design, and the reconstruction algorithm. The

  16. Testing Na+ in blood

    PubMed Central

    Lava, Sebastiano A.G.; Bianchetti, Mario G.; Milani, Gregorio P.

    2017-01-01

    Abstract Both direct potentiometry and indirect potentiometry are currently used for Na+ testing in blood. These measurement techniques show good agreement as long as protein and lipid concentrations in blood remain normal. In severely ill patients, indirect potentiometry commonly leads to relevant errors in Na+ estimation: 25% of specimens show a disagreement between direct and indirect potentiometry, which is ≥4 mmol/L (mostly spuriously elevated Na+ level due to low circulating albumin concentration). There is a need for increased awareness of the poor performance of indirect potentiometry in some clinical settings.

  17. Effects of farmhouse hotel and paper mill effluents on bacterial community structures in sediment and surface water of Nanxi River, China.

    PubMed

    Lu, Xiao-Ming; Lu, Peng-Zhen

    2014-11-01

    The pyrosequencing technique was used to evaluate bacterial community structures in sediment and surface water samples taken from Nanxi River receiving effluents from a paper mill and a farmhouse hotel, respectively. For each sample, 4,610 effective bacterial sequences were selected and used to do the analysis of diversity and abundance, respectively. Bacterial phylotype richness in the sediment sample without effluent input was higher than the other samples, and the surface water sample with addition of effluent from the paper mill contained the least richness. Effluents from both the paper mill and farmhouse hotel have a potential to reduce the bacterial diversity and abundance in the sediment and surface water, especially it is more significant in the sediment. The effect of the paper mill effluent on the sediment and surface water bacterial communities was more serious than that of the farmhouse hotel effluent. Characterization of microbial community structures in the sediment and surface water from two tributaries of the downstream river indicated that various effluents from the paper mill and farmhouse hotel have the similar potential to decrease the natural variability in riverine microbial ecosystems.

  18. Wheelchairmanship Project. A Program to Educate Personnel in the Transportation, Hotel and Restaurant, and Entertainment Industries in Improved Techniques for Serving Disabled People. Final Report.

    ERIC Educational Resources Information Center

    Smith, Anita P.; And Others

    In a project designed to train customer service personnel in improved methods of assisting the physically disabled, audio-visual training materials were developed and presented during 2-week courses involving 1,058 employees at transportation, hotel/restaurant, and entertainment centers in 25 cities. The participants judged the training program…

  19. 41 CFR 301-74.14 - Are there any special requirements for sponsoring or funding a conference at a hotel, motel or...

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 41 Public Contracts and Property Management 4 2011-07-01 2011-07-01 false Are there any special requirements for sponsoring or funding a conference at a hotel, motel or other place of public accommodation... Responsibilities § 301-74.14 Are there any special requirements for sponsoring or funding a conference at a...

  20. 41 CFR 301-74.14 - Are there any special requirements for sponsoring or funding a conference at a hotel, motel or...

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 41 Public Contracts and Property Management 4 2012-07-01 2012-07-01 false Are there any special requirements for sponsoring or funding a conference at a hotel, motel or other place of public accommodation... Responsibilities § 301-74.14 Are there any special requirements for sponsoring or funding a conference at a...

  1. 41 CFR 301-74.9 - Are there any special requirements for sponsoring or funding a conference at a hotel, motel or...

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 41 Public Contracts and Property Management 4 2014-07-01 2014-07-01 false Are there any special requirements for sponsoring or funding a conference at a hotel, motel or other place of public accommodation... Responsibilities § 301-74.9 Are there any special requirements for sponsoring or funding a conference at a...

  2. 41 CFR 301-74.14 - Are there any special requirements for sponsoring or funding a conference at a hotel, motel or...

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 41 Public Contracts and Property Management 4 2013-07-01 2012-07-01 true Are there any special requirements for sponsoring or funding a conference at a hotel, motel or other place of public accommodation... Responsibilities § 301-74.14 Are there any special requirements for sponsoring or funding a conference at a...

  3. Increasing Performance of the Two-Role Work Strategy: A Study of the International College Hotel and Training Center in Thailand

    ERIC Educational Resources Information Center

    Dhevabanchachai, Nate-tra; Wattanacharoensil, Walanchalee

    2013-01-01

    This research paper aims to identify the factors that will increase the performance and professionalism of the associates by using the study of the Salaya Pavilion Hotel Training Center (SPH) in Thailand as a case sample. In the study, staffs with two roles, called associates, were assessed for their job performance and motivation. Employing…

  4. [Preventive health control of U. S. emigrants at the beginning of 20th century on the example of hotel "Emigrants" in Rijeka].

    PubMed

    Rotim Malvić, Jasna

    2015-01-01

    Rijeka inscribed herself on the list of great European emigration ports like Hamburg, Bremen, Liverpool in the end of the year 1903 when a ship of the British Cunard Line established a travel line from Rijeka to New York. Up to the year 1914, 317639 passengers - emigrants travelled to America from the port of Rijeka. The large flow of people caused problems for the city, for that reason, already in 1906 did the Hungarian ministry of home affairs started the construction of a grandiose building intended for the emigrants. When it was opened in 1908 it was named Hotel Emigrants and had a capacity of 2500 guests. The name Hotel was given to him because of the highest construction and sanitary standards applied during his construction, but also because of comfort provided for the emigrants, large bright dormitories, living rooms, one big and spacious terrace and a number of smaller ones indicated more to a touristic hotel than to a house for emigrants. Health surveillance of emigrants was performed by Dr. David Friedman, Dr. Arturo Jellouscheg and Dr. Emil Tauffer. They were in charge in front of the Maritime Gubernia in Rijeka, the U.S. consulate in Rijeka and the Adria Maritime Society. Although the city authorities and the Hungarian authorities boasted of the hotel and the rigid medical control over immigrants which was done there, American authorities have still often returned some emigrants, at the expense of the company, after inspection at Ellis Island revealing that before landing some individuals are sick.

  5. 41 CFR 301-74.14 - Are there any special requirements for sponsoring or funding a conference at a hotel, motel or...

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 41 Public Contracts and Property Management 4 2010-07-01 2010-07-01 false Are there any special requirements for sponsoring or funding a conference at a hotel, motel or other place of public accommodation... Responsibilities § 301-74.14 Are there any special requirements for sponsoring or funding a conference at a...

  6. An Evaluation of Manpower Training Needs in the Hotel-Restaurant Industry on Kauai, 1968, with Recommendations on Programs, Sources of Students, Instructors, and Funds.

    ERIC Educational Resources Information Center

    Lloyd, Robert W.

    This report, requested and funded by a committee of community leaders, investigates the recruiting, training and employment of cooks, waitresses, maids, and small business managers needed on the island of Kauai through the year 1973. Projected increases in tourism and hotel construction indicate substantial need for well trained personnel. Courses…

  7. Forecasting Training Needs in the Hotel, Catering and Tourism Sector: A Comparative Analysis of Results from Regional Studies in Three European Countries.

    ERIC Educational Resources Information Center

    Giffard, Andre; Guegnard, Christine; Strietska-Ilina, Olga

    2001-01-01

    A pilot study on the hotel, catering, and tourism sector was conducted in the Burgundy region of France, Northwest region of the Czech Republic, and Podravje region of Slovenia. Three main kinds of factors of change were brought out. The first, evoked in Slovenia and the Czech Republic, concerned the opening of borders. Typical trends were…

  8. Comparison of human and Hotelling observer performance for a fan-beam CT signal detection task

    PubMed Central

    Sanchez, Adrian A.; Sidky, Emil Y.; Reiser, Ingrid; Pan, Xiaochuan

    2013-01-01

    Purpose: A human observer study was performed for a signal detection task for the case of fan-beam x-ray computed tomography. Hotelling observer (HO) performance was calculated for the same detection task without the use of efficient channels. By considering the full image covariance produced by the filtered backprojection (FBP) algorithm and avoiding the use of channels in the computation of HO performance, the authors establish an absolute upper bound on signal detectability. Therefore, this study serves as a baseline for relating human and ideal observer performance in the case of fan-beam CT. Methods: Eight human observers participated in a two-alternative forced choice experiment where the signal of interest was a small simulated ellipsoid in the presence of independent, identically distributed Gaussian detector noise. Theoretical performance of the HO, which is equivalent to the ideal observer in this case (see Sec. 13.2.12 in Barrett and Myers [Foundations of Image Science (Wiley, Hoboken, NJ, 2004)], was also computed and compared to the performance of the human observers. In addition to a reference FBP implementation, two FBP implementations with inherent loss of HO signal detectability (e.g., by apodizing the ramp filter) were also investigated. Each of these latter two implementations takes the form of a discrete-to-discrete linear operator (i.e., a matrix), which has a nontrivial null-space resulting in the loss of detectability. Results: Estimated observer detectability index (\\documentclass[12pt]{minimal}\\begin{document}$\\hat{d}_A$\\end{document}d^A) values for the human observers and SNR values for the HO were obtained. While Hanning filtering in the FBP implementation with a cutoff frequency of 1/4 of the Nyquist frequency reduces HO SNR (due to the reconstruction matrix's nontrivial null-space), this filtering was shown to consistently improve human observer performance. By contrast, increasing the image pixel size was seen to have a comparable

  9. Investigation of sudden death from Mycobacterium tuberculosis in a foreign-born worker at a resort hotel.

    PubMed

    Grabau, John C; Hughes, Stephen E; Rodriguez, Edwin M; Sommer, Jamie N; Troy, Eleanor T

    2004-01-01

    A 60 year-old man born in Central America died suddenly in the hallway of his residence on the grounds of a resort hotel where he worked as a dishwasher. The dishwashing station was in a large, poorly ventilated area where a substantial number of food service workers (cooks, wait staff, bus persons, dishwashers, supervisors, etc.) shared air space with the index patient. Several social contacts of the patient reported that he had been coughing for many months before his death. The County Department Of Health conducted a contact investigation, which identified 171 individuals in need of follow-up. Thirty-six percent of those tested in the first round were tuberculin skin test-positive; a second round of testing yielded a 15% (8 of 52) conversion rate.

  10. Factors affecting the quality of hospital hotel services from the patients and their companions’ point of view: A national study in Iran

    PubMed Central

    Shirzadi, Seyed Majid; Raeissi, Pouran; Nasiripour, Amir Ashkan; Tabibi, Seyed Jamaleddin

    2016-01-01

    Background: The hospitality design of a hospital is a complex process that depends on careful planning, systematic thinking, and consideration of various factors. This study aimed to determine the viewpoints of patients and their relatives on factors affecting hospital hotel services in Iran in 2015. The results of this study can be used to design a suitable model for the assessment and improvement of hospitality service quality. Materials and Methods: In this cross-sectional descriptive study, 10 hospitals of Iran were included. The subjects of the study included 480 patients and their companions from different internal and surgical wards. Simple random sampling method was performed at the hospitals, where patients were selected through stratified sampling based on hospital wards, and in each ward, through systematic sampling based on the bed numbers. A researcher-made questionnaire was used as the study tool which was developed through reviewing the literature and opinions of experts. Its internal reliability was determined based on Cronbach's alpha coefficient (α =0.85). Results: In reviewing the eleven aspects of hospital hotel services regarding the patients’ and their companions’ viewpoint, services related to all aspects, whether human, economic, operational, personnel identification, safety, health care services, physical, clinical welfare, cultural, patient guidance, or public welfare services, received mean scores of higher than three (out of five). Conclusion: The present study showed that in the patients’ and their companions’ viewpoint, factors affecting hospital hotel services in the country are very important. The tool used in this study can be a criterion for assessing the status of the hotel services of the country's major hospitals, so accordingly, the assessment and improvement of the existing conditions can be possible. PMID:27904592

  11. Contribution of (222)Rn-bearing water to indoor radon and indoor air quality assessment in hot spring hotels of Guangdong, China.

    PubMed

    Song, Gang; Wang, Xinming; Chen, Diyun; Chen, Yongheng

    2011-04-01

    This study investigates the contribution of radon ((222)Rn)-bearing water to indoor (222)Rn in thermal baths. The (222)Rn concentrations in air were monitored in the bathroom and the bedroom. Particulate matter (PM, both PM(10) and PM(2.5)) and carbon dioxide (CO(2)) were also monitored with portable analyzers. The bathrooms were supplied with hot spring water containing 66-260 kBq m(-3) of (222)Rn. The results show that the spray of hot spring water from the bath spouts is the dominant mechanism by which (222)Rn is released into the air of the bathroom, and then it diffuses into the bedroom. Average (222)Rn level was 110-410% higher in the bedrooms and 510-1200% higher in the bathrooms compared to the corresponding average levels when there was no use of hot spring water. The indoor (222)Rn levels were influenced by the (222)Rn concentrations in the hot spring water and the bathing times. The average (222)Rn transfer coefficients from water to air were 6.2 × 10(-4)-4.1 × 10(-3). The 24-h average levels of CO(2) and PM(10) in the hotel rooms were 89% and 22% higher than the present Indoor Air Quality (IAQ) standard of China. The main particle pollutant in the hotel rooms was PM(2.5). Radon and PM(10) levels in some hotel rooms were at much higher concentrations than guideline levels, and thus the potential health risks to tourists and especially to the hotel workers should be of great concern, and measures should be taken to lower inhalation exposure to these air pollutants.

  12. Direct estimation and correction of bias from temporally variable non-stationary noise in a channelized Hotelling model observer

    NASA Astrophysics Data System (ADS)

    Fetterly, Kenneth A.; Favazza, Christopher P.

    2016-08-01

    Channelized Hotelling model observer (CHO) methods were developed to assess performance of an x-ray angiography system. The analytical methods included correction for known bias error due to finite sampling. Detectability indices ({{d}\\prime} ) corresponding to disk-shaped objects with diameters in the range 0.5-4 mm were calculated. Application of the CHO for variable detector target dose (DTD) in the range 6-240 nGy frame-1 resulted in {{d}\\prime} estimates which were as much as 2.9×  greater than expected of a quantum limited system. Over-estimation of {{d}\\prime}<˜ 3.0 was presumed to be a result of bias error due to temporally variable non-stationary noise. Statistical theory which allows for independent contributions of ‘signal’ from a test object (o) and temporally variable non-stationary noise (ns) was developed. The theory demonstrates that the biased dβ\\prime is the sum of the detectability indices associated with the test object ≤ft(d\\text{o}\\prime\\right) and non-stationary noise (d\\text{ns}\\prime ). Given the nature of the imaging system and the experimental methods, d\\text{o}\\prime cannot be directly determined independent of d\\text{ns}\\prime . However, methods to estimate d\\text{ns}\\prime independent of d\\text{o}\\prime were developed. In accordance with the theory, d\\text{ns}\\prime was subtracted from experimental estimates of dβ\\prime , providing an unbiased estimate of d\\text{o}\\prime . Estimates of d\\text{o}\\prime exhibited trends consistent with expectations of an angiography system that is quantum limited for high DTD and compromised by detector electronic readout noise for low DTD conditions. Results suggest that these methods provide d\\text{o}\\prime estimates which are accurate and precise for d\\text{o}\\prime~≥slant ˜ 1.0 . Further, results demonstrated that the source of bias was detector electronic readout noise. In summary, this work presents theory and methods to test for the presence of bias

  13. Combining a wavelet transform with a channelized Hotelling observer for tumor detection in 3D PET oncology imaging

    NASA Astrophysics Data System (ADS)

    Lartizien, Carole; Tomei, Sandrine; Maxim, Voichita; Odet, Christophe

    2007-03-01

    This study evaluates new observer models for 3D whole-body Positron Emission Tomography (PET) imaging based on a wavelet sub-band decomposition and compares them with the classical constant-Q CHO model. Our final goal is to develop an original method that performs guided detection of abnormal activity foci in PET oncology imaging based on these new observer models. This computer-aided diagnostic method would highly benefit to clinicians for diagnostic purpose and to biologists for massive screening of rodents populations in molecular imaging. Method: We have previously shown good correlation of the channelized Hotelling observer (CHO) using a constant-Q model with human observer performance for 3D PET oncology imaging. We propose an alternate method based on combining a CHO observer with a wavelet sub-band decomposition of the image and we compare it to the standard CHO implementation. This method performs an undecimated transform using a biorthogonal B-spline 4/4 wavelet basis to extract the features set for input to the Hotelling observer. This work is based on simulated 3D PET images of an extended MCAT phantom with randomly located lesions. We compare three evaluation criteria: classification performance using the signal-to-noise ratio (SNR), computation efficiency and visual quality of the derived 3D maps of the decision variable λ. The SNR is estimated on a series of test images for a variable number of training images for both observers. Results: Results show that the maximum SNR is higher with the constant-Q CHO observer, especially for targets located in the liver, and that it is reached with a smaller number of training images. However, preliminary analysis indicates that the visual quality of the 3D maps of the decision variable λ is higher with the wavelet-based CHO and the computation time to derive a 3D λ-map is about 350 times shorter than for the standard CHO. This suggests that the wavelet-CHO observer is a good candidate for use in our guided

  14. Na+ coordination at the Na2 site of the Na+/I- symporter.

    PubMed

    Ferrandino, Giuseppe; Nicola, Juan Pablo; Sánchez, Yuly E; Echeverria, Ignacia; Liu, Yunlong; Amzel, L Mario; Carrasco, Nancy

    2016-09-13

    The sodium/iodide symporter (NIS) mediates active I(-) transport in the thyroid-the first step in thyroid hormone biosynthesis-with a 2 Na(+): 1 I(-) stoichiometry. The two Na(+) binding sites (Na1 and Na2) and the I(-) binding site interact allosterically: when Na(+) binds to a Na(+) site, the affinity of NIS for the other Na(+) and for I(-) increases significantly. In all Na(+)-dependent transporters with the same fold as NIS, the side chains of two residues, S353 and T354 (NIS numbering), were identified as the Na(+) ligands at Na2. To understand the cooperativity between the substrates, we investigated the coordination at the Na2 site. We determined that four other residues-S66, D191, Q194, and Q263-are also involved in Na(+) coordination at this site. Experiments in whole cells demonstrated that these four residues participate in transport by NIS: mutations at these positions result in proteins that, although expressed at the plasma membrane, transport little or no I(-) These residues are conserved throughout the entire SLC5 family, to which NIS belongs, suggesting that they serve a similar function in the other transporters. Our findings also suggest that the increase in affinity that each site displays when an ion binds to another site may result from changes in the dynamics of the transporter. These mechanistic insights deepen our understanding not only of NIS but also of other transporters, including many that, like NIS, are of great medical relevance.

  15. Risk factors of alcohol problem drinking among female bar/hotel workers in Moshi, Tanzania: a multi-level analysis.

    PubMed

    Ao, Trong Thanh-Hoang; Sam, Noel; Kiwelu, Ireen; Mahal, Ajay; Subramanian, S V; Wyshak, Grace; Kapiga, Saidi

    2011-02-01

    There is limited information on alcohol problem drinking, which has been associated with sexually transmitted infections (STIs), including HIV, among female bar/hotel workers in Africa. This paper aimed to identify the individual- and facility-level determinants of alcohol problem drinking in this setting. Problem drinking was defined based on the CAGE alcohol screening scale. Multi-level logistic regression was used to identify individual- and facility-level factors associated with problem drinking. About 37.3% of women (N = 1629) were classified as having probable or definite problem drinking. In multi-level analysis, main characteristics associated with problem drinking included: having 3-4 partners in the past 5 years compared to having 1-2, used a condom in the last sex comparing to non-use, history of transactional sex, having more pregnancies, and facilities whose employees do not live on the premises. Interventions which combine alcohol and sexual risk reduction counseling are urgently needed in this population.

  16. Tomography-like retrieval of auroral volume emission ratios for the 31 January 2008 Hotel Payload 2 event

    NASA Astrophysics Data System (ADS)

    Enell, C.-F.; Gustavsson, B.; Brändström, B. U. E.; Sergienko, T. I.; Verronen, P. T.; Rydesäter, P.; Sandahl, I.

    2012-01-01

    Quantitative tomography-like volume estimates of the N2+(1N) emission at 427.8 nm, the O(1S) emission at 557.7 nm and the O(1D) emission at 630.0 nm can be retrieved from data from the Auroral Large Imaging System (ALIS) remote-controlled spectral imagers operated at field stations in northern Sweden and Norway. This paper presents a case study of a quiet auroral arc passing over the common volume of the imagers in the evening of 31 January 2008, before the launch of the Hotel Payload 2 (HotPay 2) rocket from Andøya Rocket Range. The reconstructed spectroscopic ratios at the lower altitudes close to the mesopause region can be used as indicators of the NO and O profiles, as the atomic oxygen O(1S) and O(1D) states are excited partly through chemical reactions. The profiles of the ratios of the volume emission rates ɛ557.7 and ɛ427.8 observed by ALIS over northern Norway show nothing unambiguously unusual within the accuracy of the calibration and retrieval, whereas HotPay 2 indicated subsidence of lower thermospheric air, with higher NO concentrations. This is consistent with observations of NO and CO by satellite instruments, which indicate subsidence in vortex filaments only in the NW as seen from the Scandinavian mainland.

  17. A Multi-Period Optimization Model for Service Providers Using Online Reservation Systems: An Application to Hotels.

    PubMed

    Xu, Ming; Jiao, Yan; Li, Xiaoming; Cao, Qingfeng; Wang, Xiaoyang

    2015-01-01

    This paper presents a multi-period optimization model for high margin and zero salvage products in online distribution channels with classifying customers based on number of products required. Taking hotel customers as an example, one is regular customers who reserve rooms for one day, and the other is long term stay (LTS) customers who reserve rooms for a number of days. LTS may guarantee a specific amount of demand and generate opportunity income for a certain number of periods, meanwhile with risk of punishment incurred by overselling. By developing an operational optimization model and exploring the effects of parameters on optimal decisions, we suggest that service providers should make decisions based on the types of customers, number of products required, and duration of multi-period to reduce the loss of reputation and obtain more profit; at the same time, multi-period buying customers should buy products early. Finally, the paper conducts a numerical experiment, and the results are consistent with prevailing situations.

  18. Delineation and hydrologic effects of a gasoline leak at Stovepipe Wells Hotel, Death Valley National Monument, California

    USGS Publications Warehouse

    Buono, A.; Packard, Elaine M.

    1982-01-01

    Ground water is the only local source of water available to the Stovepipe Wells Hotel facilities of the Death Valley National Monument, California. A leak in a service station storage tank caused the formation of a gasoline layer overlying the water table, creating the potential for contamination of the water supply. The maximum horizontal extent of the gasoline layer was mathematically estimated to be 1,300 feet downgradient from the leaky gasoline tank. Exploratory drilling detected the gasoline layer between 900 and 1,400 feet downgradient and between 50 and 150 feet upgradient from the source. Traces of the soluble components of gasoline were also found in the aquifer 150 feet upgradient, and 250 feet distant from the source perpendicular to the direction of ground-water movement. The gasoline spill is not likely to have an effect on the supply wells located 0.4 mile south of the leak source, which is nearly perpendicular to the direction of ground-water movement and the primary direction of gasoline movement in the area. No effect on phreatophytes 2 miles downgradient from the layer is likely, but the potential effects of gasoline vapors within the unsaturated zone on local xerophytes are not known. (USGS)

  19. Evaluation of six channelized Hotelling observers in combination with a contrast sensitivity function to predict human observer performance

    NASA Astrophysics Data System (ADS)

    Goffi, Marco; Veldkamp, Wouter J. H.; van Engen, Ruben E.; Bouwman, Ramona W.

    2015-03-01

    Standard methods to quantify image quality (IQ) may not be adequate for clinical images since they depend on uniform backgrounds and linearity. Statistical model observers are not restricted to these limitations and might be suitable for IQ evaluation of clinical images. One of these statistical model observers is the channelized Hotelling observer (CHO), where the images are filtered by a set of channels. The aim of this study was to evaluate six different channel sets, with an additional filter to simulate the human contrast sensitivity function (CSF), in their ability to predict human observer performance. For this evaluation a two alternative forced choice experiment was performed with two types of background structures (white noise (WN) and clustered lumpy background (CLB)), 5 disk-shaped objects with different diameters and 3 different signal energies. The results show that the correlation between human and model observers have a diameter dependency for some channel sets in combination with CLBs. The addition of the CSF reduces this diameter dependency and in some cases improves the correlation coefficient between human- and model observer. For the CLB the Partial Least Squares channel set shows the highest correlation with the human observer (r2=0.71) and for WN backgrounds it was the Gabor-channel set with CSF (r2=0.72). This study showed that for some channels there is a high correlation between human and model observer, which suggests that the CHO has potential as a tool for IQ analysis of digital mammography systems.

  20. Internal noise in channelized Hotelling observer (CHO) study of detectability index-differential phase contrast CT vs. conventional CT

    NASA Astrophysics Data System (ADS)

    Tang, Xiangyang; Yang, Yi

    2014-03-01

    The channelized Hotelling observer (CHO) model, wherein internal noise plays an important role to account for the psychophysiological uncertainty in human's visual perception, has found extensive applications in the assessment of image quality in nuclear medicine, mammography and conventional CT. Recently, we extended its application to investigating the detectability index of differential phase contrast (DPC) CT-an emerging CT technology with the potential of increasing the capability in soft tissue differentiation. We found that the quantitative determination of internal noise in the CHO study of DPC-CT's detectability index should differ from that in the conventional CT. It is believed that the root cause of such a difference lies in the distinct noise spectra between the DPC-CT and conventional CT. In this paper, we present the preliminary results and investigate the adequate strategies to quantitatively determine the internal noise of CHO model for its application in the assessment of image quality in DPC-CT and its comparison with that of the conventional CT.

  1. Optimization of medical imaging display systems: using the channelized Hotelling observer for detecting lung nodules: experimental study

    NASA Astrophysics Data System (ADS)

    Platisa, Ljiljana; Vansteenkiste, Ewout; Goossens, Bart; Marchessoux, Cédric; Kimpe, Tom; Philips, Wilfried

    2009-02-01

    Medical-imaging systems are designed to aid medical specialists in a specific task. Therefore, the physical parameters of a system need to optimize the task performance of a human observer. This requires measurements of human performance in a given task during the system optimization. Typically, psychophysical studies are conducted for this purpose. Numerical observer models have been successfully used to predict human performance in several detection tasks. Especially, the task of signal detection using a channelized Hotelling observer (CHO) in simulated images has been widely explored. However, there are few studies done for clinically acquired images that also contain anatomic noise. In this paper, we investigate the performance of a CHO in the task of detecting lung nodules in real radiographic images of the chest. To evaluate variability introduced by the limited available data, we employ a commonly used study of a multi-reader multi-case (MRMC) scenario. It accounts for both case and reader variability. Finally, we use the "oneshot" methods to estimate the MRMC variance of the area under the ROC curve (AUC). The obtained AUC compares well to those reported for human observer study on a similar data set. Furthermore, the "one-shot" analysis implies a fairly consistent performance of the CHO with the variance of AUC below 0.002. This indicates promising potential for numerical observers in optimization of medical imaging displays and encourages further investigation on the subject.

  2. [New scientific arguments for further reducing the use of tobacco, also in the hotel, restaurant and catering business].

    PubMed

    Peters, R J G

    2007-01-20

    The prohibition of smoking in public places that has been implemented in various European countries has led to a noticeable decrease in the number of hospital admissions for acute myocardial infarction. This effect became manifest within one year after the adoption of the measure. A significant proportion of the benefit can probably be ascribed to the reduction of passive smoking. The recently published INTERHEART study is a case-control study involving approximately 12,500 patients who had been admitted for an acute myocardial infarction and approximately 14,500 apparently healthy controls. The study was carried out in 52 countries and reveals that an increased risk of acute myocardial infarction as the result of tobacco use can be seen in all investigated countries and races. Smoking as well as the chewing or sniffing of tobacco are associated with an increased risk; there is also a clear proportional relationship between the level of tobacco use and the degree of risk. Moreover, passive smoking was again shown to be an important and avoidable cause ofacute myocardial infarction. In the Netherlands, smoking in public buildings has been prohibited since 1990, with the exception of the hotel, restaurant and catering industry. It would be a good thing if this exception were eliminated in our country as well.

  3. A Multi-Period Optimization Model for Service Providers Using Online Reservation Systems: An Application to Hotels

    PubMed Central

    Xu, Ming; Jiao, Yan; Li, Xiaoming; Cao, Qingfeng; Wang, Xiaoyang

    2015-01-01

    This paper presents a multi-period optimization model for high margin and zero salvage products in online distribution channels with classifying customers based on number of products required. Taking hotel customers as an example, one is regular customers who reserve rooms for one day, and the other is long term stay (LTS) customers who reserve rooms for a number of days. LTS may guarantee a specific amount of demand and generate opportunity income for a certain number of periods, meanwhile with risk of punishment incurred by overselling. By developing an operational optimization model and exploring the effects of parameters on optimal decisions, we suggest that service providers should make decisions based on the types of customers, number of products required, and duration of multi-period to reduce the loss of reputation and obtain more profit; at the same time, multi-period buying customers should buy products early. Finally, the paper conducts a numerical experiment, and the results are consistent with prevailing situations. PMID:26147663

  4. Na Cauda do Cometa

    NASA Astrophysics Data System (ADS)

    Voelzke, M. R.

    2009-01-01

    Quando viam um cometa, os antigos gregos imaginavam uma estrela com uma vasta cabeleira. Não à toa, a palavra deriva do termo koma, que significa cabelo. Constituídos por fragmentos de gelo e gases, os cometas possuem um núcleo sólido, que pode ter vários quilômetros de diâmetro, e uma cauda que sempre aponta na direção contrária ao Sol, devido aos ventos solares. Graças à aparência de pontos luminosos em movimento (ao contrário de outros astros, que parecem estáticos), esses corpos celestes foram interpretados por diferentes povos com muito misticismo, inspirando mitos tanto de boas-novas como de maus presságios. Conheça algumas dessas histórias:

  5. Antibiotic resistance and mecA characterization of coagulase-negative staphylococci isolated from three hotels in London, UK.

    PubMed

    Xu, Zhen; Mkrtchyan, Hermine V; Cutler, Ronald R

    2015-01-01

    Antibiotic resistance in bacteria isolated from non-healthcare environments, is a potential problem to public health. In our survey a total of 71 coagulase negative staphylococci (CNS) belonging to 11 different species were isolated from three large hotels in London, UK. The most prevalent species was Staphylococcus haemolyticus, with S. hominis, S. warneri, S. cohnii, and Staphylococcus epidermidis commonly detected. Antimicrobial susceptibilities and carriage of the mecA gene were determined for all of these isolates. Most (85.9%) staphylococci were resistant to multiple antibiotics with all displaying increased susceptibility toward penicillin, fusidic acid, erythromycin, and cefepime. Twenty-one (29.5%) of the isolates were mecA positive, however MIC values to oxacillin, normally associated with the carriage of mecA, varied widely in this group (from 0.06 to 256 mg/L). Fifteen of the twenty-one mecA positive isolates carried SCCmec of these seven were type V, one type I, one type II, and one type IV. Additionally, five of these 15 isolates carried a previously unreported type, 1A, which involves an association between class A mec complex and ccr type 1. The remaining six of the 21 isolates were non-typeable and carried a combination of class A mec complex and ccrC. In addition to this, we also report on new MLST types which were assigned for five S. epidermidis isolates. Four out of these five isolates had MICs between 0.06 and 256 mg/L to oxacillin and would be regarded as clinically susceptible but one isolate had a high oxacillin MIC of 256 mg/L. We demonstrated widespread multiple drug resistance among different staphylococcal species isolated from non-healthcare environments highlighting the potential for these species to act as a reservoir for methicillin and other forms of drug resistance.

  6. Comparison of Channelized Hotelling and Human Observers inDetermining Optimum OS-EM Reconstruction Parameters for MyocardialSPECT

    SciTech Connect

    Gilland, Karen L.; Tsui, Benjamin M.W.; Qi, Yujin; Gullberg,Grant T.

    2005-07-01

    The performance of the Channelized Hotelling Observer (CHO)was compared to that of human observers for determining optimumparameters for the iterative OS-EM image reconstruction method for thetask of defect detection in myocardial SPECT images. The optimumparameters were those that maximized defect detectability in the SPECTimages. Low noise, parallel SPECT projection data, with and without ananterior, inferior or lateral LV wall defect, were simulated using theMonte Carlo method. Poisson noise was added to generate noisyrealizations. Data were reconstructed using OS-EM at 1&4subsets/iteration and at 1, 3, 5, 7&9 iterations. Images wereconverted to 2D short-axis slices with integer pixel values. The CHO used3 radially-symmetric, 2D channels, with varying levels of internalobserver noise. For each parameter setting, 600 defect-present and 600defect-absent image vectors were used to calculate the detectabilityindex (dA). The human observers rated the likelihood that a defect waspresent in a specified location. For each parameter setting, the AUC wasestimated from 48 defect-present and 48 defect-absent images. Thecombined human observer results showed the optimum parameter settingcould be in the range 5-36 updates ([number of subsets]/iteration enumber of iterations). The CHO results showed the optimum parametersetting to be 4-5 updates. The performance of the CHO was much moresensitive to the reconstruction parameter setting than was that of thehuman observers. The rankings of the CHO detectability values did notchange with varying levels of internal noise.

  7. Development and application of a channelized Hotelling observer for DBT optimization on structured background test images with mass simulating targets

    NASA Astrophysics Data System (ADS)

    Petrov, Dimitar; Michielsen, Koen; Cockmartin, Lesley; Zhang, Gouzhi; Young, Kenneth; Marshall, Nicholas; Bosmans, Hilde

    2016-03-01

    Digital breast tomosynthesis (DBT) is a 3D mammography technique that promises better visualization of low contrast lesions than conventional 2D mammography. A wide range of parameters influence the diagnostic information in DBT images and a systematic means of DBT system optimization is needed. The gold standard for image quality assessment is to perform a human observer experiment with experienced readers. Using human observers for optimization is time consuming and not feasible for the large parameter space of DBT. Our goal was to develop a model observer (MO) that can predict human reading performance for standard detection tasks of target objects within a structured phantom and subsequently apply it in a first comparative study. The phantom consists of an acrylic semi-cylindrical container with acrylic spheres of different sizes and the remaining space filled with water. Three types of lesions were included: 3D printed spiculated and non-spiculated mass lesions along with calcification groups. The images of the two mass lesion types were reconstructed with 3 different reconstruction methods (FBP, FBP with SRSAR, MLTRpr) and read by human readers. A Channelized Hotelling model observer was created for the non-spiculated lesion detection task using five Laguerre-Gauss channels, tuned for better performance. For the non-spiculated mass lesions a linear relation between the MO and human observer results was found, with correlation coefficients of 0.956 for standard FBP, 0.998 for FBP with SRSAR and 0.940 for MLTRpr. Both the MO and human observer percentage correct results for the spiculated masses were close to 100%, and showed no difference from each other for every reconstruction algorithm.

  8. Na+ coordination at the Na2 site of the Na+/I− symporter

    PubMed Central

    Ferrandino, Giuseppe; Nicola, Juan Pablo; Sánchez, Yuly E.; Echeverria, Ignacia; Liu, Yunlong; Amzel, L. Mario; Carrasco, Nancy

    2016-01-01

    The sodium/iodide symporter (NIS) mediates active I− transport in the thyroid—the first step in thyroid hormone biosynthesis—with a 2 Na+: 1 I− stoichiometry. The two Na+ binding sites (Na1 and Na2) and the I− binding site interact allosterically: when Na+ binds to a Na+ site, the affinity of NIS for the other Na+ and for I− increases significantly. In all Na+-dependent transporters with the same fold as NIS, the side chains of two residues, S353 and T354 (NIS numbering), were identified as the Na+ ligands at Na2. To understand the cooperativity between the substrates, we investigated the coordination at the Na2 site. We determined that four other residues—S66, D191, Q194, and Q263—are also involved in Na+ coordination at this site. Experiments in whole cells demonstrated that these four residues participate in transport by NIS: mutations at these positions result in proteins that, although expressed at the plasma membrane, transport little or no I−. These residues are conserved throughout the entire SLC5 family, to which NIS belongs, suggesting that they serve a similar function in the other transporters. Our findings also suggest that the increase in affinity that each site displays when an ion binds to another site may result from changes in the dynamics of the transporter. These mechanistic insights deepen our understanding not only of NIS but also of other transporters, including many that, like NIS, are of great medical relevance. PMID:27562170

  9. Solidification of NaCl-NaF eutectic in space

    NASA Technical Reports Server (NTRS)

    Yue, A. S.; Yu, J. G.

    1974-01-01

    Continuous and discontinuous NaF fibers, embedded in a NaCl matrix, have been produced in space and on earth, respectively. The production of continuous fibers in a eutectic mixture was attributed to the absence of convection current in the liquid during solidification in space. Image transmission and optical transmittance measurements of transverse sections of the space-grown and earth-grown ingots were made with a light microscope and a spectrometer. It was found that better optical properties were obtained from samples grown in space. This was attributed to a better alignment of NaF fibers along the ingot axis.

  10. WE-E-18A-09: Application of a Channelized Hotelling Observer Model to Evaluate Angiographic Imaging Equipment

    SciTech Connect

    Favazza, C; Fetterly, K; Hangiandreou, N; Leng, S; Schueler, B

    2014-06-15

    Purpose: To develop and apply an observer model to objectively evaluate and compare the performance of different angiographic imaging equipment and acquisition variables. Methods: Image Acquisition— Iodine-based phantoms were created with target diameters: 0.5, 1, 2, and 4 mm. The phantoms were imaged using both planes of a bi-plane angiography system with detector pixel dimensions 0.1542 mm{sup 2} and 0.1842 mm{sup 2}, respectively. All four phantoms were imaged with magnification factors 1.5, 1.25 and 1 and with the large and small focal spots. Phantom position and the dose per frame (0.12– 0.24 μ Gy/frame) were varied for a single phantom size, magnification and focal spot. Observer Model— For each experimental condition, 1200 signal-present and signal-absent images were acquired and a detectability index (d') was calculated with a Gabor-channelized Hotelling observer (CHO) model. Detectability indices were evaluated as a function of dose, phantom size, and magnification. The model was then applied to compare d' of the two imaging planes and focal spots. Uncertainty in d' was estimated by bootstrapping the data and by examining the shift-variance of systems. Results: Detectability indices varied linearly with magnification and the square root of dose. For the 2 and 4 mm phantoms, d' varied linearly with diameter. For the 0.5 and 1 mm phantoms, d' expectedly deviated from this linear relationship due to substantial detector and focal spot blurring of the phantoms. The small focal spot yielded up to 50% greater d' values than the large focal spot. For the two detectors, differences in d' did not exceed the estimated ∼7% error. Conclusions: The detectability indices predictably scaled with dose, diameter, magnification, and focal spot size and serve to validate the model. Results demonstrate statistically similar target detectability for both investigated detectors, despite differences in pixel dimensions. This CHO model provides a framework to evaluate

  11. Na+ recirculation and isosmotic transport.

    PubMed

    Larsen, E H; Møbjerg, N

    2006-01-01

    The Na(+) recirculation theory for solute-coupled fluid absorption is an expansion of the local osmosis concept introduced by Curran and analyzed by Diamond & Bossert. Based on studies on small intestine the theory assumes that the observed recirculation of Na(+) serves regulation of the osmolarity of the absorbate. Mathematical modeling reproducing bioelectric and hydrosmotic properties of small intestine and proximal tubule, respectively, predicts a significant range of observations such as isosmotic transport, hyposmotic transport, solvent drag, anomalous solvent drag, the residual hydraulic permeability in proximal tubule of AQP1 (-/-) mice, and the inverse relationship between hydraulic permeability and the concentration difference needed to reverse transepithelial water flow. The model reproduces the volume responses of cells and lateral intercellular space (lis) following replacement of luminal NaCl by sucrose as well as the linear dependence of volume absorption on luminal NaCl concentration. Analysis of solvent drag on Na(+) in tight junctions provides explanation for the surprisingly high metabolic efficiency of Na(+) reabsorption. The model predicts and explains low metabolic efficiency in diluted external baths. Hyperosmolarity of lis is governed by the hydraulic permeability of the apical plasma membrane and tight junction with 6-7 mOsm in small intestine and < or = 1 mOsm in proximal tubule. Truly isosmotic transport demands a Na(+) recirculation of 50-70% in small intestine but might be barely measurable in proximal tubule. The model fails to reproduce a certain type of observations: The reduced volume absorption at transepithelial osmotic equilibrium in AQP1 knockout mice, and the stimulated water absorption by gallbladder in diluted external solutions. Thus, it indicates cellular regulation of apical Na(+) uptake, which is not included in the mathematical treatment.

  12. Lesson Plans Used with Housekeeping Employees of the Sheraton Anchorage Hotel. Conversation and Reading Skills Correlated with Skill Books 1-3 of the "Laubach Way to English." Workplace Curriculum.

    ERIC Educational Resources Information Center

    Smith, Polly; King, Richard

    This packet contains four sets of lesson plans designed for the workplace curriculum for housekeeping employees at the Sheraton Anchorage Hotel (Anchorage, Alaska), as part of the Anchorage Workplace Literacy Program. The lesson plans, which are correlated with Laubach literacy method skills books levels 1-3, include conversation (dialogue,…

  13. Vocational Education and Training for the Hotel and Catering Industry in the Federal Republic of Germany. Report of a Visiting Party. Studies in Vocational Education and Training in the Federal Republic of Germany. Number Eight.

    ERIC Educational Resources Information Center

    Ripper, Chris, Ed.; Russell, Russ, Ed.

    A party of vocational educators from the United Kingdom (UK) traveled to the Federal Republic of Germany (FRG) to examine West German vocational education and training for the hotel and catering industry. During the study, the investigators examined the training with respect to regulations, the content of training, and the structure of the…

  14. From hotel to home.

    PubMed

    Philpot, Terry

    In the heart of Manhattan, the Common Ground organisation helps the city's low paid and homeless to find health care and work. Man of these people have complex needs, including mental health and drug and alcohol problems.

  15. Aquifer-test evaluation and potential effects of increased ground-water pumpage at the Stovepipe Wells Hotel area, Death Valley National Monument, California

    USGS Publications Warehouse

    Woolfenden, L.R.; Martin, Peter; Baharie, Brian

    1988-01-01

    Ground-water use in the Stovepipe Wells Hotel area in Death Valley National Monument is expected to increase significantly if the nonpotable, as well as potable, water supply is treated by reverse osmosis. During the peak tourist season, October through March, ground-water pumpage could increase by 37,500 gallons per day, or 76%. The effects of this additional pumpage on water levels in the area, particularly near a strand of phreatophytes about 10,000 feet east of the well field, are of concern. In order to evaluate the effects of increased pumpage on water levels in the Stovepipe Wells Hotel area well field, two aquifer tests were performed at the well field to determine the transmissivity and storage coefficients of the aquifer. Analysis of the aquifer test determined that a transmissivity of 1,360 feet squared per day was representative of the aquifer. The estimated value of transmissivity and the storage-coefficient values that are representative of confined (1.2 x .0004) and unconfined (0.25) conditions were used in the Theis equation to calculate the additional drawdown that might occur after 1, 10, and 50 years of increased pumpage. The drawdown calculated by using the lower storage-coefficient value represents the maximum additional drawdown that might be expected from the assumed increase in pumpage; the drawdown calculated by using the higher storage-coefficient value represents the minimum additional drawdown. Calculated additional drawdowns after 50 years of pumping range from 7.8 feet near the pumped well to 2.4 feet at the phreatophyte stand assuming confined conditions, and from 5.7 feet near the pumped well to 0.3 foot at the phreatophyte stand assuming unconfined conditions. Actual drawdowns probably will be somewhere between these values. Drawdowns measured in observation wells during 1973-85, in response to an average pumpage of 34,200 gallons per day at the Stovepipe Wells Hotel well field, are similar to the drawdowns calculated by the Theis

  16. The influence of corporate social responsibility, ability, reputation, and transparency on hotel customer loyalty in the U.S.: a gender-based approach.

    PubMed

    Kim, Sung-Bum; Kim, Dae-Young

    2016-01-01

    This research explored a conceptual framework incorporating interrelationships among corporate social responsibility (CSR), corporate ability (CA), corporate reputation (CR), and CSR-related transparency on customer loyalty within the hotel context. In this study, we also analyzed consumers' propensity to support CSR initiatives through the socio-demographic indicator of gender. We used independent sample t test and multiple regression analysis to test hypotheses based on 487 responses from American participants. Four antecedents (i.e., CSR, CA, CR, and transparency) exhibited favorable effects on customer loyalty. Among these four factors, the positively perceived CSR initiatives had a greater impact on customer loyalty. In addition, according to our findings, female participants were more likely to have a positive perception of the four antecedents than males.

  17. Transactions of the twenty-third water reactor safety information meeting to be held at Bethesda Marriott Hotel, Bethesda, Maryland, October 23--25, 1995

    SciTech Connect

    Monteleone, S.

    1995-09-01

    This report contains summaries of papers on reactor safety research to be presented at the 23rd Water Reactor Safety Information Meeting at the Bethesda Marriott Hotel, Bethesda, Maryland, October 23--25, 1995. The summaries briefly describe the programs and results of nuclear safety research sponsored by the Office of Nuclear Regulatory, Research, US NRC. Summaries of invited papers concerning nuclear safety issues from US government laboratories, the electric utilities, the nuclear industry, and from foreign governments and industry are also included. The summaries have been compiled in one report to provide a basis for meaningful discussion and information exchange during the course of the meeting and are given in the order of their presentation in each session.

  18. Sexual behavior, psychosocial and knowledge differences between consistent, inconsistent and non-users of condoms: a study of female bar and hotel workers in Moshi, Tanzania.

    PubMed

    Tassiopoulos, Katherine K; Seage, George R; Sam, Noel E; Ao, Trong T H; Masenga, Elisante J; Hughes, Michael D; Kapiga, Saidi H

    2006-07-01

    Understanding psychosocial, sexual behavior and knowledge differences between never, inconsistent and consistent condom users can improve interventions to increase condom use in resource-poor countries, but they have not been adequately studied. We examined these differences in a cohort of 961 female hotel and bar workers in Moshi, Tanzania. Forty-nine percent of women reported no condom use; 39% reported inconsistent use, and 12% reported consistent use. Women with multiple sexual partners in the past five years were less likely to be consistent rather than inconsistent users as were women who had ever exchanged sex for gifts or money. Inconsistent users had higher condom knowledge and higher perceived acceptability of condom use than did never users, but they did not differ from consistent users by these factors. There are important differences between women by level of condom use. These findings can help inform interventions to increase condom use.

  19. Proceedings of the Annual Symposium on Frequency Control (37th). 1-3 June 1983, Marriott Hotel, Philadelphia, Pennsylvania.

    DTIC Science & Technology

    1983-06-03

    Multiple Frequency Microwave Source. AD-P002 459 Synchronization and Tracking with Synchronous Oscillators. AD-P002 460 Frequency (Standard) Combiner...Behavior in the System H2 0-NaOH- Si02 and its Relationship to the Hydrothermal Growth of Quartz. AD-P002 469 Standard Characterization Methods for the...COMPONENT PART NOTICE (CON’T) AD#: TITLE: AD-P002 491 A New Frequency for Piezoelectric Resonator Measurement. AD-P002 492 Measuring Method of Equivalent

  20. Astrocytes generate Na+-mediated metabolic waves.

    PubMed

    Bernardinelli, Yann; Magistretti, Pierre J; Chatton, Jean-Yves

    2004-10-12

    Glutamate-evoked Na+ increase in astrocytes has been identified as a signal coupling synaptic activity to glucose consumption. Astrocytes participate in multicellular signaling by transmitting intercellular Ca2+ waves. Here we show that intercellular Na+ waves are also evoked by activation of single cultured cortical mouse astrocytes in parallel with Ca2+ waves; however, there are spatial and temporal differences. Indeed, maneuvers that inhibit Ca2+ waves also inhibit Na+ waves; however, inhibition of the Na+/glutamate cotransporters or enzymatic degradation of extracellular glutamate selectively inhibit the Na+ wave. Thus, glutamate released by a Ca2+ wave-dependent mechanism is taken up by the Na+/glutamate cotransporters, resulting in a regenerative propagation of cytosolic Na+ increases. The Na+ wave gives rise to a spatially correlated increase in glucose uptake, which is prevented by glutamate transporter inhibition. Therefore, astrocytes appear to function as a network for concerted neurometabolic coupling through the generation of intercellular Na+ and metabolic waves.

  1. Europlanet NA2 Science Networking

    NASA Astrophysics Data System (ADS)

    Harri, Ari-Matti; Szego, Karoly; Genzer, Maria; Schmidt, Walter; Krupp, Norbert; Lammer, Helmut; Kallio, Esa; Haukka, Harri

    2013-04-01

    Europlanet RI / NA2 Science Networking [1] focused on determining the major goals of current and future European planetary science, relating them to the Research Infrastructure that the Europlanet RI project [2] developed, and placing them in a more global context. NA2 also enhanced the ability of European planetary scientists to participate on the global scene with their own agenda-setting projects and ideas. The Networking Activity NA2 included five working groups, aimed at identifying key science issues and producing reference books on major science themes that will bridge the gap between the results of present and past missions and the scientific preparation of the future ones. Within the Europlanet RI project (2009-2012) the NA2 and NA2-WGs organized thematic workshops, an expert exchange program and training groups to improve the scientific impact of this Infrastructure. The principal tasks addressed by NA2 were: • Science activities in support to the optimal use of data from past and present space missions, involving the broad planetary science community beyond the "space club" • Science activities in support to the preparation of future planetary missions: Earth-based preparatory observations, laboratory studies, R&D on advanced instrumentation and exploration technologies for the future, theory and modeling etc. • Develop scientific activities, joint publications, dedicated meetings, tools and services, education activities, engaging the public and industries • Update science themes and addressing the two main scientific objectives • Prepare and support workshops of the International Space Science Institute (ISSI) in Bern and • Support Trans National Activities (TNAs), Joined Research Activities (JRAs) and the Integrated and Distributed Information Service (IDIS) of the Europlanet project These tasks were achieved by WG workshops organized by the NA2 working groups, by ISSI workshops and by an Expert Exchange Program. There were 17 official WG

  2. Sodium iron hexacyanoferrate with high Na content as a Na-rich cathode material for Na-ion batteries

    DOE PAGES

    You, Ya; Yu, Xi -Qian; Yin, Ya -Xia; ...

    2014-10-27

    Owing to the worldwide abundance and low-cost of Na, room-temperature Na-ion batteries are emerging as attractive energy storage systems for large-scale grids. Increasing the Na content in cathode material is one of the effective ways to achieve high energy density. Prussian blue and its analogues (PBAs) are promising Na-rich cathode materials since they can theoretically store two Na ions per formula. However, increasing the Na content in PBAs cathode materials is a big challenge in the current. Here we show that sodium iron hexacyanoferrate with high Na content could be obtained by simply controlling the reducing agent and reaction atmospheremore » during synthesis. The Na content can reach as high as 1.63 per formula, which is the highest value for sodium iron hexacyanoferrate. This Na-rich sodium iron hexacyanoferrate demonstrates a high specific capacity of 150 mA h g-1 and remarkable cycling performance with 90% capacity retention after 200 cycles. Furthermore, the Na intercalation/de-intercalation mechanism is systematically studied by in situ Raman, X-ray diffraction and X-ray absorption spectroscopy analysis for the first time. As a result, the Na-rich sodium iron hexacyanoferrate could function as a plenteous Na reservoir and has great potential as a cathode material toward practical Na-ion batteries.« less

  3. Sodium iron hexacyanoferrate with high Na content as a Na-rich cathode material for Na-ion batteries

    SciTech Connect

    You, Ya; Yu, Xi -Qian; Yin, Ya -Xia; Nam, Kyung -Wan; Guo, Yu -Guo

    2014-10-27

    Owing to the worldwide abundance and low-cost of Na, room-temperature Na-ion batteries are emerging as attractive energy storage systems for large-scale grids. Increasing the Na content in cathode material is one of the effective ways to achieve high energy density. Prussian blue and its analogues (PBAs) are promising Na-rich cathode materials since they can theoretically store two Na ions per formula. However, increasing the Na content in PBAs cathode materials is a big challenge in the current. Here we show that sodium iron hexacyanoferrate with high Na content could be obtained by simply controlling the reducing agent and reaction atmosphere during synthesis. The Na content can reach as high as 1.63 per formula, which is the highest value for sodium iron hexacyanoferrate. This Na-rich sodium iron hexacyanoferrate demonstrates a high specific capacity of 150 mA h g-1 and remarkable cycling performance with 90% capacity retention after 200 cycles. Furthermore, the Na intercalation/de-intercalation mechanism is systematically studied by in situ Raman, X-ray diffraction and X-ray absorption spectroscopy analysis for the first time. As a result, the Na-rich sodium iron hexacyanoferrate could function as a plenteous Na reservoir and has great potential as a cathode material toward practical Na-ion batteries.

  4. Ionic regulation of Na absorption in proximal colon: cation inhibition of electroneutral Na absorption

    SciTech Connect

    Sellin, J.H.; De Soignie, R.

    1987-01-01

    Active Na absorption (J/sub net//sup NA/) in rabbit proximal colon in vitro is paradoxically stimulated as (Na) in the bathing media is lowered with constant osmolarity. J/sub m..-->..s//sup Na/ increases almost linearly from 0 to 50 mM (Na)/sub 0/ but then plateaus and actually decreases from 50 to 140 mM (Na)/sub 0/, consistent with inhibition of an active transport process. Both lithium and Na are equally effective inhibitors of J/sub net//sup Na/, whereas choline and mannitol do not block the high rate of J/sub net//sup Na/ observed in decreased (Na)/sub 0/. Either gluconate or proprionate replacement of Cl inhibits J/sub net//sup Na/. J/sub net//sup Na/ at lowered (Na)/sub 0/ is electrically silent and is accompanied by increased Cl absorption; it is inhibited by 10/sup -3/ M amiloride and 10/sup -3/ theophylline but not by 10/sup -4/ M bumetanide. Epinephrine is equally effective at stimulating Na absorption at 50 and 140 mM (Na). Na gradient experiments are consistent with a predominantly serosal effect of the decreased (Na)/sub 0/. These results suggest that 1) Na absorption in rabbit proximal colon in vitro is stimulated by decreased (Na); 2) the effect is cation specific, both Na and Li blocking the stimulatory effect; 3) the transport is mediated by Na-H exchange and is Cl dependent but 4) is under different regulatory mechanisms than the epinephrine-sensitive Na-Cl cotransport previously described in proximal colon. Under the appropriate conditions, proximal colon absorbs Na extremely efficiently. Na-H exchange in this epithelium is cation inhibitable, either directly or by a secondary regulatory process.

  5. Deliquescence of NaCl-NaNO3 and KNO3-NaNO3 Salt Mixtures at 90C

    SciTech Connect

    Carroll, S; Craig, L; Wolery, T

    2003-12-29

    We conducted reversed deliquescence experiments in saturated NaCl-NaNO3-H2O and KNO{sub 3}-NaNO{sub 3}-H{sub 2}O systems at 90 C to determine relative humidity and solution composition. NaCl, NaNO{sub 3}, and KNO{sub 3} represent members of dust salt assemblages that are likely to deliquesce and form concentrated brines on high-level radioactive waste package surfaces in a repository environment at Yucca Mountain, NV, USA. Model predictions agree with experimental results for the NaCl-NaNO{sub 3}-H{sub 2}O system, but underestimate relative humidity by as much as 8% and solution composition by as much as 50% in the KNO{sub 3}-NaNO{sub 3}-H{sub 2}O system.

  6. Na+ Tolerance and Na+ Transport in Higher Plants

    PubMed Central

    TESTER, MARK; DAVENPORT, ROMOLA

    2003-01-01

    Tolerance to high soil [Na+] involves processes in many different parts of the plant, and is manifested in a wide range of specializations at disparate levels of organization, such as gross morphology, membrane transport, biochemistry and gene transcription. Multiple adaptations to high [Na+] operate concurrently within a particular plant, and mechanisms of tolerance show large taxonomic variation. These mechanisms can occur in all cells within the plant, or can occur in specific cell types, reflecting adaptations at two major levels of organization: those that confer tolerance to individual cells, and those that contribute to tolerance not of cells per se, but of the whole plant. Salt‐tolerant cells can contribute to salt tolerance of plants; but we suggest that equally important in a wide range of conditions are processes involving the management of Na+ movements within the plant. These require specific cell types in specific locations within the plant catalysing transport in a coordinated manner. For further understanding of whole plant tolerance, we require more knowledge of cell‐specific transport processes and the consequences of manipulation of transporters and signalling elements in specific cell types. PMID:12646496

  7. Conversion and Distribution of Lead and Tin in NaOH-NaNO3 Fusion Process

    NASA Astrophysics Data System (ADS)

    Liu, Jingxin; Guo, Xueyi

    2017-04-01

    Oxidizing alkali fusion process has been studied to extract amphoteric metals. Transformation and distribution behaviors of typical amphoteric metals Pb and Sn in the NaOH-NaNO3 fusion process are systemically studied by theoretical analysis and experimental verification done in this work. Functions of NaOH and NaNO3 in the fusion process were also investigated. The results show the fused products, Na2PbO3 and Na2SnO3, are captured in the flux, and Na2PbO4 is speculated to reduce to Pb(II) in the following leaching process. By measuring solubility data of NaOH-Na2SnO3-PbO-H2O system, a strategy of crystallization is proposed to separate Sn with Pb in concentrated alkaline solution, and slice Na2Sn(OH)6 is obtained as a product.

  8. Conversion and Distribution of Lead and Tin in NaOH-NaNO3 Fusion Process

    NASA Astrophysics Data System (ADS)

    Liu, Jingxin; Guo, Xueyi

    2016-12-01

    Oxidizing alkali fusion process has been studied to extract amphoteric metals. Transformation and distribution behaviors of typical amphoteric metals Pb and Sn in the NaOH-NaNO3 fusion process are systemically studied by theoretical analysis and experimental verification done in this work. Functions of NaOH and NaNO3 in the fusion process were also investigated. The results show the fused products, Na2PbO3 and Na2SnO3, are captured in the flux, and Na2PbO4 is speculated to reduce to Pb(II) in the following leaching process. By measuring solubility data of NaOH-Na2SnO3-PbO-H2O system, a strategy of crystallization is proposed to separate Sn with Pb in concentrated alkaline solution, and slice Na2Sn(OH)6 is obtained as a product.

  9. A long-life Na-air battery based on a soluble NaI catalyst.

    PubMed

    Yin, Wen-Wen; Shadike, Zulipiya; Yang, Yin; Ding, Fei; Sang, Lin; Li, Hong; Fu, Zheng-Wen

    2015-02-11

    A Na-air battery with NaI dissolved in a typical organic electrolyte could run up to 150 cycles with a capacity limit of 1000 mA h g(-1). The low charge voltage plateau of 3.2 V vs. Na(+)/Na in a Na-air battery should mainly be attributed to the oxidation reaction of active iodine anions.

  10. Silicene for Na-ion battery applications

    NASA Astrophysics Data System (ADS)

    Zhu, Jiajie; Schwingenschlögl, Udo

    2016-09-01

    Na-ion batteries are promising candidates to replace Li-ion batteries in large scale applications because of the advantages in natural abundance and cost of Na. Silicene has potential as the anode in Li-ion batteries but so far has not received attention with respect to Na-ion batteries. In this context, freestanding silicene, a graphene-silicene-graphene heterostructure, and a graphene-silicene superlattice are investigated for possible application in Na-ion batteries, using first-principles calculations. The calculated Na capacities of 954 mAh/g for freestanding silicene and 730 mAh/g for the graphene-silicene superlattice (10% biaxial tensile strain) are highly competitive and potentials of \\gt 0.3 {{V}} against the Na{}+/Na potential exceed the corresponding value of graphite. In addition, the diffusion barriers are predicted to be \\lt 0.3 {eV}.

  11. Traumatic impact of a fire disaster on survivors--a 25-year follow-up of the 1978 hotel fire in Borås, Sweden.

    PubMed

    Lundin, Tom; Jansson, Lennart

    2007-01-01

    The objective of this study was to investigate the long-term psychological and mental health outcomes among survivors of a disastrous hotel fire. A 25-year follow-up investigation among adolescent and young adult survivors of a fire disaster was conducted in Borås, Sweden. A self-evaluation questionnaire and four self-rating scales - the IES-22, PTSS-10, GHQ-28 and SoC - were sent by mail to the participants. The results from the self-reported data showed low levels of psychiatric illness. Moreover, the respondents reported a low level of traumatic stress symptoms. More than 50% of the participants stated that the fire had a determining effect on their lives. Sixteen (21.3%) respondents indicated that the fire still had an impact on their daily lives. Differences between men and women were reported in most of the self-rating scales. The results indicate that a traumatizing experience (such as a fire disaster) still had a small effect on psychological health in a long-term perspective.

  12. Perceived discrimination and smoking among rural-to-urban migrant women working as restaurant/hotel workers and sex workers in China

    PubMed Central

    Shin, Sanghyuk S.; Wan, Xia; Wang, Qian; Raymond, H. Fisher; Liu, Huilin; Ding, Ding; Yang, Gonghuan; Novotny, Thomas E.

    2013-01-01

    Background Smoking may be a coping mechanism for psychosocial stress caused by discrimination. Methods We conducted a cross-sectional survey of rural-to-urban migrant women working as restaurant/hotel workers (RHWs) and those working as sex workers (FSWs) in 10 Chinese cities to investigate whether perceived discrimination is associated with smoking. We interviewed RHWs at medical examination clinics and FSWs at entertainment venues. Modified Poisson regression was used to estimate prevalence ratios. Results Of the 1696 RHWs and 532 FSWs enrolled, 155 (9.1%) and 63 (11.8%) reported perceived discrimination, respectively. Perceived discrimination was independently associated with ever tried smoking (prevalence ratio [PR], 1.71; 95% confidence interval [CI], 1.31–2.23) and current smoking (PR, 2.52; 95% CI, 1.32–4.79) among RHWs and ever tried smoking (PR, 1.36; 95% CI, 1.16–1.61) and current smoking (PR, 1.63; 95% CI, 1.28–2.06) among FSWs. Discussion Perceived discrimination is associated with higher prevalence of smoking among rural-to-urban migrant women in China. PMID:22389186

  13. Revisiting the hydration structure of aqueous Na().

    PubMed

    Galib, M; Baer, M D; Skinner, L B; Mundy, C J; Huthwelker, T; Schenter, G K; Benmore, C J; Govind, N; Fulton, J L

    2017-02-28

    A combination of theory, X-ray diffraction (XRD) and extended x-ray absorption fine structure (EXAFS) are used to probe the hydration structure of aqueous Na(+). The high spatial resolution of the XRD measurements corresponds to Qmax = 24 Å(-1) while the first-reported Na K-edge EXAFS measurements have a spatial resolution corresponding to 2k = Qmax = 16 Å(-1). Both provide an accurate measure of the shape and position of the first peak in the Na-O pair distribution function, gNaO(r). The measured Na-O distances of 2.384 ± 0.003 Å (XRD) and 2.37 ± 0.024 Å (EXAFS) are in excellent agreement. These measurements show a much shorter Na-O distance than generally reported in the experimental literature (Na-Oavg ∼ 2.44 Å) although the current measurements are in agreement with recent neutron diffraction measurements. The measured Na-O coordination number from XRD is 5.5 ± 0.3. The measured structure is compared with both classical and first-principles density functional theory (DFT) simulations. Both of the DFT-based methods, revPBE and BLYP, predict a Na-O distance that is too long by about 0.05 Å with respect to the experimental data (EXAFS and XRD). The inclusion of dispersion interactions (-D3 and -D2) significantly worsens the agreement with experiment by further increasing the Na-O distance by 0.07 Å. In contrast, the use of a classical Na-O Lennard-Jones potential with SPC/E water accurately predicts the Na-O distance as 2.39 Å although the Na-O peak is over-structured with respect to experiment.

  14. The effect of Na vapor on the Na content of chondrules

    NASA Technical Reports Server (NTRS)

    Lewis, R. Dean; Lofgren, Gary E.; Franzen, Hugo F.; Windom, Kenneth E.

    1993-01-01

    Chondrules contain higher concentrations of volatiles (Na) than expected for melt droplets in the solar nebula. Recent studies have proposed that chondrules may have formed under non-canonical nebular conditions such as in particle/gas-rich clumps. Such chondrule formation areas may have contained significant Na vapor. To test the hypothesis of whether a Na-rich vapor would minimize Na volatilization reaction rates in a chondrule analog and maintain the Na value of the melt, experiments were designed where a Na-rich vapor could be maintained around the sample. A starting material with a melting point lower that typical chondrules was required to keep the logistics of working with Na volatilization from NaCl within the realm of feasibility. The Knippa basalt, a MgO-rich alkali olivine basalt with a melting temperature of 1325 +/- 5 C and a Na2O content of 3.05 wt%, was used as the chondrule analog. Experiments were conducted in a 1 atm, gas-mixing furnace with the fO2 controlled by a CO/CO2 gas mixture and fixed at the I-W buffer curve. To determine the extent of Na loss from the sample, initial experiments were conducted at high temperatures (1300 C - 1350 C) for duration of up to 72 h without a Na-rich vapor present. Almost all (up to 98%) Na was volatilized in runs of 72 h. Subsequent trials were conducted at 1330 C for 16 h in the presence of a Na-rich vapor, supplied by a NaCl-filled crucible placed in the bottom of the furnace. Succeeding Knudsen cell weight-loss mass-spectrometry analysis of NaCl determined the P(sub Na) for these experimental conditions to be in the 10(exp -6) atm range. This value is considered high for nebula conditions but is still plausible for non-canonical environments. In these trials the Na2O content of the glass was maintained or in some cases increased; Na2O values ranged from 2.62% wt to 4.37% wt. The Na content of chondrules may be controlled by the Na vapor pressure in the chondrule formation region. Most heating events capable

  15. Growth of binary organic NLO crystals: m.NA-p.NA and m.NA-CNA system

    NASA Technical Reports Server (NTRS)

    Singh, N. B.; Henningsen, T.; Hopkins, R. H.; Mazelsky, R.

    1993-01-01

    Experiments were carried out to grow 3.Nitroaniline (m.NA) crystals doped with 4.Nitroaniline (p.NA) and 2.chloro 4.Nitroaniline (CNA). The measured undercooling for m.NA, p.NA, and CNA were 0.21 tm K, 0.23 tm K, and 0.35 tm K respectively, where tm represents the melting temperature of the pure component. Because of the crystals' large heat of fusion and large undercooling, it was not possible to grow good quality crystals with low thermal gradients. In the conventional two-zone Bridgman furnace we had to raise the temperature of the hot zone above the decomposition temperature of CNA, p.NA, and m.NA to achieve the desired thermal gradient. To avoid decomposition, we used an unconventional Bridgman furnace. Two immiscible liquids, silicone oil and ethylene glycol, were used to build a special two-zone Bridgman furnace. A temperature gradient of 18 K/cm was achieved without exceeding the decomposition temperature of the crystal. The binary crystals, m.NA-p.NA and m.NA-CNA, were grown in centimeter size in this furnace. X-ray and optical characterization showed good optical quality.

  16. Modification of single Na+ channels by batrachotoxin.

    PubMed Central

    Quandt, F N; Narahashi, T

    1982-01-01

    The modifications in the properties of voltage-gated Na+ channels caused by batrachotoxin were studied by using the patch clamp method for measuring single channel currents from excised membranes of N1E-115 neuroblastoma cells. The toxin-modified open state of the Na+ channel has a decreased conductance in comparison to that of normal Na+ channels. The lifetime of the modified open state is drastically prolonged, and channels now continue to open during a maintained depolarization so that the probability of a channel being open becomes constant. Modified and normal open states of Na+ channels coexist in batrachotoxin-exposed membrane patches. Unlike the normal condition, Na+ channels exposed to batrachotoxin open spontaneously at large negative potentials. These spontaneous openings apparently cause the toxin-induced increase in Na+ permeability which, in turn, causes membrane depolarization. PMID:6292915

  17. Maintaining the NA atmosphere of Mercury

    NASA Astrophysics Data System (ADS)

    Killen, R. M.; Morgan, T. H.

    1993-02-01

    The possible sources of the Na atmosphere of Mercury are calculatively studied. The likely structure, composition, and temperature of the planet's upper crust is examined along with the probable flux of Na from depth by grain boundary diffusion and by Knudsen flow. The creation of fresh regolith is considered along with mechanisms for supplying Na from the surface to the exosphere. The implications of the calculations for the probable abundances in the regolith are discussed.

  18. Maintaining the Na atmosphere of Mercury

    NASA Technical Reports Server (NTRS)

    Killen, Rosemary M.; Morgan, Thomas H.

    1993-01-01

    The possible sources of the Na atmosphere of Mercury are calculatively studied. The likely structure, composition, and temperature of the planet's upper crust is examined along with the probable flux of Na from depth by grain boundary diffusion and by Knudsen flow. The creation of fresh regolith is considered along with mechanisms for supplying Na from the surface to the exosphere. The implications of the calculations for the probable abundances in the regolith are discussed.

  19. NA-NET numerical analysis net

    SciTech Connect

    Dongarra, J. . Dept. of Computer Science Oak Ridge National Lab., TN ); Rosener, B. . Dept. of Computer Science)

    1991-12-01

    This report describes a facility called NA-NET created to allow numerical analysts (na) an easy method of communicating with one another. The main advantage of the NA-NET is uniformity of addressing. All mail is addressed to the Internet host na-net.ornl.gov'' at Oak Ridge National Laboratory. Hence, members of the NA-NET do not need to remember complicated addresses or even where a member is currently located. As long as moving members change their e-mail address in the NA-NET everything works smoothly. The NA-NET system is currently located at Oak Ridge National Laboratory. It is running on the same machine that serves netlib. Netlib is a separate facility that distributes mathematical software via electronic mail. For more information on netlib consult, or send the one-line message send index'' to netlib{at}ornl.gov. The following report describes the current NA-NET system from both a user's perspective and from an implementation perspective. Currently, there are over 2100 members in the NA-NET. An average of 110 mail messages pass through this facility daily.

  20. NA-NET numerical analysis net

    SciTech Connect

    Dongarra, J. |; Rosener, B.

    1991-12-01

    This report describes a facility called NA-NET created to allow numerical analysts (na) an easy method of communicating with one another. The main advantage of the NA-NET is uniformity of addressing. All mail is addressed to the Internet host ``na-net.ornl.gov`` at Oak Ridge National Laboratory. Hence, members of the NA-NET do not need to remember complicated addresses or even where a member is currently located. As long as moving members change their e-mail address in the NA-NET everything works smoothly. The NA-NET system is currently located at Oak Ridge National Laboratory. It is running on the same machine that serves netlib. Netlib is a separate facility that distributes mathematical software via electronic mail. For more information on netlib consult, or send the one-line message ``send index`` to netlib{at}ornl.gov. The following report describes the current NA-NET system from both a user`s perspective and from an implementation perspective. Currently, there are over 2100 members in the NA-NET. An average of 110 mail messages pass through this facility daily.

  1. Simulation study of Na-majorite

    NASA Astrophysics Data System (ADS)

    Dymshits, A.; Vinograd, V.; Paulsen, N.; Winkler, B.; Perchuk, L.; Bobrov, A.

    2009-04-01

    Garnets, which are found as inclusions in diamonds, often have the excess of Na2O and SiO2 [Stachel, 2001]. Experimental studies suggest that Na is incorporated in pyrope-rich garnet via the coupled substitution Mg+Al=Na+Si [Bobrov et al., 2008]. This study is concerned with the determination of the structure and the thermodynamic properties of NaGrt (Na2MgSi5O12), which is assumed to be the end-member of pyrope-rich garnets with the excess of Na2O and SiO2. Static lattice energy calculations were performed with the program GULP [Gale & Rohl, 2003] using the force-field model [Vinograd et al., 2007] for 200 structures of Na2MgSi5O12 composition. These structures were prepared from Ia3-d pyrope Mg3Al2Si3O12 by replacing all octahedral Al atoms with Si and 2/3 of Mg atoms with Na. The distribution of Mg and Na was varied randomly. The static energies of these structures were cluster expanded using 8 pairwise effective cluster interactions (ECI). The ECIs were used to constrain Monte Carlo simulations within a 4×4×4 supercell (NNN exchangeable sites). The annealing experiments have shown that the lowest energy structure has the space group I4

  2. Painful Na-channelopathies: an expanding universe.

    PubMed

    Waxman, Stephen G

    2013-07-01

    The universe of painful Na-channelopathies--human disorders caused by mutations in voltage-gated sodium channels--has recently expanded in three dimensions. We now know that mutations of sodium channels cause not only rare genetic 'model disorders' such as inherited erythromelalgia and channelopathy-associated insensitivity to pain but also common painful neuropathies. We have learned that mutations of NaV1.8, as well as mutations of NaV1.7, can cause painful Na-channelopathies. Moreover, recent studies combining atomic level structural models and pharmacogenomics suggest that the goal of genomically guided pain therapy may not be unrealistic.

  3. Na+/Ca2+ exchange and Na+/K+-ATPase in the heart

    PubMed Central

    Shattock, Michael J; Ottolia, Michela; Bers, Donald M; Blaustein, Mordecai P; Boguslavskyi, Andrii; Bossuyt, Julie; Bridge, John H B; Chen-Izu, Ye; Clancy, Colleen E; Edwards, Andrew; Goldhaber, Joshua; Kaplan, Jack; Lingrel, Jerry B; Pavlovic, Davor; Philipson, Kenneth; Sipido, Karin R; Xie, Zi-Jian

    2015-01-01

    This paper is the third in a series of reviews published in this issue resulting from the University of California Davis Cardiovascular Symposium 2014: Systems approach to understanding cardiac excitation–contraction coupling and arrhythmias: Na+ channel and Na+ transport. The goal of the symposium was to bring together experts in the field to discuss points of consensus and controversy on the topic of sodium in the heart. The present review focuses on cardiac Na+/Ca2+ exchange (NCX) and Na+/K+-ATPase (NKA). While the relevance of Ca2+ homeostasis in cardiac function has been extensively investigated, the role of Na+ regulation in shaping heart function is often overlooked. Small changes in the cytoplasmic Na+ content have multiple effects on the heart by influencing intracellular Ca2+ and pH levels thereby modulating heart contractility. Therefore it is essential for heart cells to maintain Na+ homeostasis. Among the proteins that accomplish this task are the Na+/Ca2+ exchanger (NCX) and the Na+/K+ pump (NKA). By transporting three Na+ ions into the cytoplasm in exchange for one Ca2+ moved out, NCX is one of the main Na+ influx mechanisms in cardiomyocytes. Acting in the opposite direction, NKA moves Na+ ions from the cytoplasm to the extracellular space against their gradient by utilizing the energy released from ATP hydrolysis. A fine balance between these two processes controls the net amount of intracellular Na+ and aberrations in either of these two systems can have a large impact on cardiac contractility. Due to the relevant role of these two proteins in Na+ homeostasis, the emphasis of this review is on recent developments regarding the cardiac Na+/Ca2+ exchanger (NCX1) and Na+/K+ pump and the controversies that still persist in the field. PMID:25772291

  4. Objective comparison of lesion detectability in low and medium-energy collimator iodine-123 mIBG images using a channelized Hotelling observer

    NASA Astrophysics Data System (ADS)

    Gregory, Rebecca A.; Murray, Iain; Gear, Jonathan; Aldridge, Matthew D.; Levine, Daniel; Fowkes, Lucy; Waddington, Wendy A.; Chua, Sue; Flux, Glenn

    2017-01-01

    Iodine-123 mIBG imaging is widely regarded as a gold standard for diagnostic studies of neuroblastoma and adult neuroendocrine cancer although the optimal collimator for tumour imaging remains undetermined. Low-energy (LE) high-resolution (HR) collimators provide superior spatial resolution. However due to septal penetration of high-energy photons these provide poorer contrast than medium-energy (ME) general-purpose (GP) collimators. LEGP collimators improve count sensitivity. The aim of this study was to objectively compare the lesion detection efficiency of each collimator to determine the optimal collimator for diagnostic imaging. The septal penetration and sensitivity of each collimator was assessed. Planar images of the patient abdomen were simulated with static scans of a Liqui-Phil™ anthropomorphic phantom with lesion-shaped inserts, acquired with LE and ME collimators on 3 different manufacturers’ gamma camera systems (Skylight (Philips), Intevo (Siemens) and Discovery (GE)). Two-hundred normal and 200 single-lesion abnormal images were created for each collimator. A channelized Hotelling observer (CHO) was developed and validated to score the images for the likelihood of an abnormality. The areas under receiver-operator characteristic (ROC) curves, Az, created from the scores were used to quantify lesion detectability. The CHO ROC curves for the LEHR collimators were inferior to the GP curves for all cameras. The LEHR collimators resulted in statistically significantly smaller Azs (p  <  0.05), of on average 0.891  ±  0.004, than for the MEGP collimators, 0.933  ±  0.004. In conclusion, the reduced background provided by MEGP collimators improved 123I mIBG image lesion detectability over LEHR collimators that provided better spatial resolution.

  5. Task-based detectability comparison of exponential transformation of free-response operating characteristic (EFROC) curve and channelized Hotelling observer (CHO)

    NASA Astrophysics Data System (ADS)

    Khobragade, P.; Fan, Jiahua; Rupcich, Franco; Crotty, Dominic J.; Gilat Schmidt, Taly

    2016-03-01

    This study quantitatively evaluated the performance of the exponential transformation of the free-response operating characteristic curve (EFROC) metric, with the Channelized Hotelling Observer (CHO) as a reference. The CHO has been used for image quality assessment of reconstruction algorithms and imaging systems and often it is applied to study the signal-location-known cases. The CHO also requires a large set of images to estimate the covariance matrix. In terms of clinical applications, this assumption and requirement may be unrealistic. The newly developed location-unknown EFROC detectability metric is estimated from the confidence scores reported by a model observer. Unlike the CHO, EFROC does not require a channelization step and is a non-parametric detectability metric. There are few quantitative studies available on application of the EFROC metric, most of which are based on simulation data. This study investigated the EFROC metric using experimental CT data. A phantom with four low contrast objects: 3mm (14 HU), 5mm (7HU), 7mm (5 HU) and 10 mm (3 HU) was scanned at dose levels ranging from 25 mAs to 270 mAs and reconstructed using filtered backprojection. The area under the curve values for CHO (AUC) and EFROC (AFE) were plotted with respect to different dose levels. The number of images required to estimate the non-parametric AFE metric was calculated for varying tasks and found to be less than the number of images required for parametric CHO estimation. The AFE metric was found to be more sensitive to changes in dose than the CHO metric. This increased sensitivity and the assumption of unknown signal location may be useful for investigating and optimizing CT imaging methods. Future work is required to validate the AFE metric against human observers.

  6. WE-G-204-02: Utility of a Channelized Hotelling Model Observer Over a Large Range of Angiographic Exposure Levels

    SciTech Connect

    Fetterly, K; Favazza, C

    2015-06-15

    Purpose: Mathematical model observers provide a figure of merit that simultaneously considers a test object and the contrast, noise, and spatial resolution properties of an imaging system. The purpose of this work was to investigate the utility of a channelized Hotelling model observer (CHO) to assess system performance over a large range of angiographic exposure conditions. Methods: A 4 mm diameter disk shaped, iodine contrast test object was placed on a 20 cm thick Lucite phantom and 1204 image frames were acquired using fixed x-ray beam quality and for several detector target dose (DTD) values in the range 6 to 240 nGy. The CHO was implemented in the spatial domain utilizing 96 Gabor functions as channels. Detectability index (DI) estimates were calculated using the “resubstitution” and “holdout” methods to train the CHO. Also, DI values calculated using discrete subsets of the data were used to estimate a minimally biased DI as might be expected from an infinitely large dataset. The relationship between DI, independently measured CNR, and changes in results expected assuming a quantum limited detector were assessed over the DTD range. Results: CNR measurements demonstrated that the angiography system is not quantum limited due to relatively increasing contamination from electronic noise that reduces CNR for low DTD. Direct comparison of DI versus CNR indicates that the CHO relatively overestimates DI for low DTD and/or underestimates DI values for high DTD. The relative magnitude of the apparent bias error in the DI values was ∼20% over the 40x DTD range investigated. Conclusion: For the angiography system investigated, the CHO can provide a minimally biased figure of merit if implemented over a restricted exposure range. However, bias leads to overestimates of DI for low exposures. This work emphasizes the need to verify CHO model performance during real-world application.

  7. Computation of the ensemble channelized Hotelling observer signal-to-noise ratio for ordered-subset image reconstruction using noisy data

    NASA Astrophysics Data System (ADS)

    Soares, Edward J.; Gifford, Howard C.; Glick, Stephen J.

    2003-05-01

    We investigated the estimation of the ensemble channelized Hotelling observer (CHO) signal-to-noise ratio (SNR) for ordered-subset (OS) image reconstruction using noisy projection data. Previously, we computed the ensemble CHO SNR using a method for approximating the channelized covariance of OS reconstruction, which requires knowledge of the noise-free projection data. Here, we use a "plug-in" approach, in which noisy data is used in place of the noise-free data in the aforementioned channelized covariance approximation. Additionally, we evaluated the use of smoothing of the noisy projections before use in the covariance approximation. Additionally, we evaluated the use of smoothing of the noisy projections before use in the covariance calculation. The task was detection of a 10% contrast Gaussian signal within a slice of the MCAT phantom. Simulated projections of the MCAT phantom were scaled and Poisson noise was added to create 100 noisy signal-absent data sets. Simulated projections of the scaled signal were then added to the noisy background projections to create 100 noisy signal-present data set. These noisy data sets were then used to generate 100 estimates of the ensemble CHO SNR for reconstructions at various iterates. For comparison purposes, the same calculation was repeated with the noise-free data. The results, reported as plots of the average CHO SNR generated in this fashion, along with 95% confidence intervals, demonstrate that this approach works very well, and would allow optimization of imaging systems and reconstruction methods using a more accurate object model (i.e., real patient data).

  8. A contrast-sensitive channelized-Hotelling observer to predict human performance in a detection task using lumpy backgrounds and Gaussian signals

    NASA Astrophysics Data System (ADS)

    Park, Subok; Badano, Aldo; Gallas, Brandon D.; Myers, Kyle J.

    2007-03-01

    Previously, a non-prewhitening matched filter (NPWMF) incorporating a model for the contrast sensitivity of the human visual system was introduced for modeling human performance in detection tasks with different viewing angles and white-noise backgrounds by Badano et al. But NPWMF observers do not perform well detection tasks involving complex backgrounds since they do not account for random backgrounds. A channelized-Hotelling observer (CHO) using difference-of-Gaussians (DOG) channels has been shown to track human performance well in detection tasks using lumpy backgrounds. In this work, a CHO with DOG channels, incorporating the model of the human contrast sensitivity, was developed similarly. We call this new observer a contrast-sensitive CHO (CS-CHO). The Barten model was the basis of our human contrast sensitivity model. A scalar was multiplied to the Barten model and varied to control the thresholding effect of the contrast sensitivity on luminance-valued images and hence the performance-prediction ability of the CS-CHO. The performance of the CS-CHO was compared to the average human performance from the psychophysical study by Park et al., where the task was to detect a known Gaussian signal in non-Gaussian distributed lumpy backgrounds. Six different signal-intensity values were used in this study. We chose the free parameter of our model to match the mean human performance in the detection experiment at the strongest signal intensity. Then we compared the model to the human at five different signal-intensity values in order to see if the performance of the CS-CHO matched human performance. Our results indicate that the CS-CHO with the chosen scalar for the contrast sensitivity predicts human performance closely as a function of signal intensity.

  9. Exploration of NaVOPO4 as a cathode for a Na-ion battery.

    PubMed

    Song, Jie; Xu, Maowen; Wang, Long; Goodenough, John B

    2013-06-11

    Monoclinic NaVOPO4 is explored as a cathode material for a sodium ion battery. It exhibits electrochemical activity operating at an average potential of 3.6 V (vs. Na(+)/Na) and delivers a reversible capacity of 90 mA h g(-1) at 1/15 C.

  10. Negative electrodes for Na-ion batteries.

    PubMed

    Dahbi, Mouad; Yabuuchi, Naoaki; Kubota, Kei; Tokiwa, Kazuyasu; Komaba, Shinichi

    2014-08-07

    Research interest in Na-ion batteries has increased rapidly because of the environmental friendliness of sodium compared to lithium. Throughout this Perspective paper, we report and review recent scientific advances in the field of negative electrode materials used for Na-ion batteries. This paper sheds light on negative electrode materials for Na-ion batteries: carbonaceous materials, oxides/phosphates (as sodium insertion materials), sodium alloy/compounds and so on. These electrode materials have different reaction mechanisms for electrochemical sodiation/desodiation processes. Moreover, not only sodiation-active materials but also binders, current collectors, electrolytes and electrode/electrolyte interphase and its stabilization are essential for long cycle life Na-ion batteries. This paper also addresses the prospect of Na-ion batteries as low-cost and long-life batteries with relatively high-energy density as their potential competitive edge over the commercialized Li-ion batteries.

  11. High NA Nicrostepper Final Optical Design Report

    SciTech Connect

    Hudyma, R

    1999-09-24

    The development of a new EUV high NA small-field exposure tool has been proposed for obtaining mask defect printability data in a timeframe several years before beta-tools are available. The imaging system for this new Micro-Exposure Tool (MET), would have a numerical aperture (NA) of about 0.3, similar to the NA for a beta-tool, but substantially larger than the 0.10 NA for the Engineering Test Stand (ETS) and 0.088 NA for the existing 10x Microstepper. This memorandum discusses the development and summarizes the performance of the camera for the MET and includes a listing of the design prescription, detailed analysis of the distortion, and analysis demonstrating the capability to resolution 30 nm features under the conditions of partially coherent illumination.

  12. Na+ binding to the Na(+)-glucose cotransporter is potential dependent.

    PubMed

    Bennett, E; Kimmich, G A

    1992-02-01

    Activity of the Na(+)-glucose cotransporter in LLC-PK1 epithelial cells was assayed by measuring sugar-induced currents (IAMG) using whole cell recording techniques. IAMG was compared among cells by standardizing the measured currents to cell size using cell capacitance measurements. IAMG at a given membrane potential was measured as a function of alpha-methylglucoside (AMG) concentration and can be fit to Michaelis-Menten kinetics. IAMG at varying Na+ concentrations can be described by the Hill equation with a Hill coefficient of 1.6 at all tested potentials. At high external Na+ levels (155 mM), Na+ is at least 90% saturating at all tested potentials. Maximal currents at a given membrane potential (Im) are calculated from the Michaelis-Menten equation fit to data measuring IAMG vs. AMG concentration at a constant Na+ concentration. Im showed potential dependence under all conditions. Potential-dependent Na+ binding rate(s) cannot alone explain the observed potential dependence of Im under saturating Na+ conditions. Therefore, because Im is potential dependent, at least one step of the transport cycle other than external Na+ binding must be potential dependent. Im was also calculated from data taken at 40 mM external Na+. At all potentials studied, Im at 155 mM Na+ is greater than Im calculated at 40 mM Na+. This implies that the rate of external Na+ binding to the transporter at 40 mM also affects the maximal transport rate. Furthermore, Im at 40 mM external Na+ increases with hyperpolarization faster than Im at 155 mM Na+. Together, these facts indicate that the rate at which Na+ binds to the transporter is also potential dependent.(ABSTRACT TRUNCATED AT 250 WORDS)

  13. Pharmacological modulation of human cardiac Na+ channels.

    PubMed

    Krafte, D S; Davison, K; Dugrenier, N; Estep, K; Josef, K; Barchi, R L; Kallen, R G; Silver, P J; Ezrin, A M

    1994-02-15

    Pharmacological modulation of human sodium current was examined in Xenopus oocytes expressing human heart Na+ channels. Na+ currents activated near -50 mV with maximum current amplitudes observed at -20 mV. Steady-state inactivation was characterized by a V1/2 value of -57 +/- 0.5 mV and a slope factor (k) of 7.3 +/- 0.3 mV. Sodium currents were blocked by tetrodotoxin with an IC50 value of 1.8 microM. These properties are consistent with those of Na+ channels expressed in mammalian myocardial cells. We have investigated the effects of several pharmacological agents which, with the exception of lidocaine, have not been characterized against cRNA-derived Na+ channels expressed in Xenopus oocytes. Lidocaine, quinidine and flecainide blocked resting Na+ channels with IC50 values of 521 microM, 198 microM, and 41 microM, respectively. Use-dependent block was also observed for all three agents, but concentrations necessary to induce block were higher than expected for quinidine and flecainide. This may reflect differences arising due to expression in the Xenopus oocyte system or could be a true difference in the interaction between human cardiac Na+ channels and these drugs compared to other mammalian Na+ channels. Importantly, however, this result would not have been predicted based upon previous studies of mammalian cardiac Na+ channels. The effects of DPI 201-106, RWJ 24517, and BDF 9148 were also tested and all three agents slowed and/or removed Na+ current inactivation, reduced peak current amplitudes, and induced use-dependent block. These data suggest that the alpha-subunit is the site of interaction between cardiac Na+ channels and Class I antiarrhythmic drugs as well as inactivation modifiers such as DPI 201-106.

  14. Na-doped optical Germanium bulk crystals

    NASA Astrophysics Data System (ADS)

    Pekar, G. S.; Singaevsky, A. F.

    2012-09-01

    In an effort to develop a material for infrared (IR) optics with improved parameters, bulk crystals of optical germanium doped with Na have been first grown and studied. Single-crystalline and coarse-crystalline Ge:Na boules of different shapes and dimensions, up to 10 kg by weight, have been grown. Sodium was incorporated into the Ge crystal during the crystal growing from the melt. Despite the fact that Na contamination in the source material was not strictly controlled, the density of Na in the grown crystals determined by the neutron activation analysis as well as by the glow discharge mass spectrometry did not exceed 1015 cm-3. Just this value may be supposed to be close to the solubility limit of Na incorporated in Ge in the course of bulk crystal growth. A first demonstration of donor behavior of Na in bulk Ge crystals is made by means of a thermoelectric type of testing. An interstitial location of Na impurity has been verified by experiments on donor drift in the dc electric field. The crystals are grown with free electron density in the range from 5ṡ1013 to 4ṡ1014 cm-3 which is optimal for using Ge crystals as an optical material for fabricating passive elements of the IR technique. A comparison between the properties of Ge:Na crystals and Ge crystals doped with Sb, a conventional impurity in optical germanium, grown under the same technological conditions and from the same intrinsic Ge as a source material, revealed a number of advantages of Ge:Na crystals; among them, the higher transparency in the IR region, smaller radiation scattering and higher regular optical transmission, lower dislocation density, more uniform distribution of electrical and optical characteristics over the crystal volume, the identity of optical parameters in the single-crystalline, and coarse-crystalline boules. No degradation of optical elements fabricated from Ge:Na crystals was detected in the course of their commercial application, starting from 1998.

  15. Anomalously high Na(+) and low Li(+) mobility in intercalated Na2Ti6O13.

    PubMed

    Ling, Chen; Zhang, Ruigang

    2017-04-12

    We report an anomalous diffusion behavior in intercalated Na2Ti6O13. Using first-principles calculations, the direct migration of inserted Na(+) along the tunnel direction is predicted to have a barrier of 0.24-0.44 eV, while the migration of inserted Li(+) along the tunnel direction has a barrier of 0.86-1.15 eV. Although Li(+) can also diffuse along a zig-zag path in the tunnel, the barrier of 0.86-0.99 eV is still much higher than that for Na(+). Our results surprisingly lead to the conclusion that the diffusion of larger Na(+) is 4-8 orders of magnitude faster than Li(+) in the same host lattice, and explain the experimentally observed exceptional rate capability of Na2Ti6O13 as the Na-ion battery anode. The anomalous diffusion behavior is attributed to the geometric features of Na2Ti6O13. For migration of Li(+) it is necessary to weaken Li-O bonds and to overcome the repulsion between Li and host Na ions simultaneously, while for Na(+) diffusion the improved Na-O bonding at the transition state partially compensates for the energy penalty from the repulsion of host Na ions.

  16. Cytosolic Na+ Controls an Epithelial Na+ Channel Via the Go Guanine Nucleotide-Binding Regulatory Protein

    NASA Astrophysics Data System (ADS)

    Komwatana, P.; Dinudom, A.; Young, J. A.; Cook, D. I.

    1996-07-01

    In tight Na+-absorbing epithelial cells, the rate of Na+ entry through amiloride-sensitive apical membrane Na+ channels is matched to basolateral Na+ extrusion so that cell Na+ concentration and volume remain steady. Control of this process by regulation of apical Na+ channels has been attributed to changes in cytosolic Ca2+ concentration or pH, secondary to changes in cytosolic Na+ concentration, although cytosolic Cl- seems also to be involved. Using mouse mandibular gland duct cells, we now demonstrate that increasing cytosolic Na+ concentration inhibits apical Na+ channels independent of changes in cytosolic Ca2+, pH, or Cl-, and the effect is blocked by GDP-β -S, pertussis toxin, and antibodies against the α -subunits of guanine nucleotide-binding regulatory proteins (Go). In contrast, the inhibitory effect of cytosolic anions is blocked by antibodies to inhibitory guanine nucleotide-binding regulatory proteins (Gi1/Gi2. It thus appears that apical Na+ channels are regulated by Go and Gi proteins, the activities of which are controlled, respectively, by cytosolic Na+ and Cl-.

  17. Cytosolic Na+ controls and epithelial Na+ channel via the Go guanine nucleotide-binding regulatory protein.

    PubMed Central

    Komwatana, P; Dinudom, A; Young, J A; Cook, D I

    1996-01-01

    In tight Na+-absorbing epithelial cells, the fate of Na+ entry through amiloride-sensitive apical membrane Na+ channels is matched to basolateral Na+ extrusion so that cell Na+ concentration and volume remain steady. Control of this process by regulation of apical Na+ channels has been attributed to changes in cytosolic Ca2+ concentration or pH, secondary to changes in cytosolic Na+ concentration, although cytosolic Cl- seems also to be involved. Using mouse mandibular gland duct cells, we now demonstrate that increasing cytosolic Na+ concentration inhibits apical Na+ channels independent of changes in cytosolic Ca2+, pH, or Cl-, and the effect is blocked by GDP-beta-S, pertussis toxin, and antibodies against the alpha-subunits of guanine nucleotide-binding regulatory proteins (Go). In contrast, the inhibitory effect of cytosolic anions is blocked by antibodies to inhibitory guanine nucleotide-binding regulatory proteins (Gi1/Gi2. It thus appears that apical Na+ channels are regulated by Go and Gi proteins, the activities of which are controlled, respectively, by cytosolic Na+ and Cl-. Images Fig. 4 PMID:8755611

  18. Laser-induced ionization of Na vapor

    SciTech Connect

    Wu, R.C.Y.; Judge, D.L.; Roussel, F.; Carre, B.; Breger, P.; Spiess, G.

    1982-01-01

    The production of Na/sub 2//sup +/ ions by off-resonant laser excitation in the 5800-6200A region mainly results from two-photon absorption by the Na/sub 2/ molecule to highly excited gerade states followed by (a) direct ionization by absorbing a third photon or (b) coupling to the molecular Na/sub 2/ D/sup 1/PI..mu.. Rydberg state which is subsequently ionized by absorbing a third photon. This mechanism, i.e., a two-photon resonance three photon ionization process, explains a recent experimental observation of Roussel et al. It is suggested that the very same mechanism is also responsible for a similar observation reported by Polak-Dingels et al in their work using two crossed Na beams. In the latter two studies the laser-induced associative ionization processes were reported to be responsible for producing the Na/sub 2//sup +/ ion. From the ratio of molecular to atomic concentration in the crossed beam experiment of Polak-Dingels et al we estimate that the cross section for producing Na/sub 2//sup +/ through laser-induced associative ionization is at least four orders of magnitude smaller than ionization through the two-photon resonance three photon ionization process in Na/sub 2/ molecules.

  19. Laser-induced ionization of Na vapor

    NASA Astrophysics Data System (ADS)

    Wu, C. Y. Robert; Judge, D. L.; Roussel, F.; Carré, B.; Breger, P.; Spiess, G.

    1982-09-01

    The production of Na2+ ions by off-resonant laser excitation in the 5800-6200Å region mainly results from two-photon absorption by the Na2 molecule to highly excited gerade states followed by (a) direct ionization by absorbing a third photon or (b) coupling to the molecular Na2 D1Πu Rydberg state which is subsequently ionized by absorbing a third photon. This mechanism, i.e., a two-photon resonance three photon ionization process, explains a recent experimental observation of Roussel et al. It is suggested that the very same mechanism is also responsible for a similar observation reported by Polak-Dingels et al in their work using two crossed Na beams. In the latter two studies the laser-induced associative ionization processes were reported to be responsible for producing the Na2+ ion. From the ratio of molecular to atomic concentration in the crossed beam experiment of Polak-Dingels et al. we estimate that the cross section for producing Na2+ through laser-induced associative ionization is at least four orders of magnitude smaller than ionization through the two-photon resonance three photon ionization process in Na2 molecules.

  20. NMR studies on Na+ transport in Synechococcus PCC 6311

    NASA Technical Reports Server (NTRS)

    Nitschmann, W. H.; Packer, L.

    1992-01-01

    The freshwater cyanobacterium Synechococcus PCC 6311 is able to adapt to grow after sudden exposure to salt (NaCl) stress. We have investigated the mechanism of Na+ transport in these cells during adaptation to high salinity. Na+ influx under dark aerobic conditions occurred independently of delta pH or delta psi across the cytoplasmic membrane, ATPase activity, and respiratory electron transport. These findings are consistent with the existence of Na+/monovalent anion cotransport or simultaneous Na+/H+ +anion/OH- exchange. Na+ influx was dependent on Cl-, Br-, NO3-, or NO2-. No Na+ uptake occurred after addition of NaI, NaHCO3, or Na2SO4. Na+ extrusion was absolutely dependent on delta pH and on an ATPase activity and/or on respiratory electron transport. This indicates that Na+ extrusion via Na+/H+ exchange is driven by primary H+ pumps in the cytoplasmic membrane. Cells grown for 4 days in 0.5 m NaCl medium, "salt-grown cells," differ from control cells by a lower maximum velocity of Na+ influx and by lower steady-state ratios of [Na+]in/[Na+]out. These results indicate that cells grown in high-salt medium increase their capacity to extrude Na+. During salt adaptation Na+ extrusion driven by respiratory electron transport increased from about 15 to 50%.

  1. Multi-domain training in healthy old age: Hotel Plastisse as an iPad-based serious game to systematically compare multi-domain and single-domain training

    PubMed Central

    Binder, Julia C.; Zöllig, Jacqueline; Eschen, Anne; Mérillat, Susan; Röcke, Christina; Schoch, Sarah F.; Jäncke, Lutz; Martin, Mike

    2015-01-01

    Finding effective training interventions for declining cognitive abilities in healthy aging is of great relevance, especially in view of the demographic development. Since it is assumed that transfer from the trained to untrained domains is more likely to occur when training conditions and transfer measures share a common underlying process, multi-domain training of several cognitive functions should increase the likelihood of such an overlap. In the first part, we give an overview of the literature showing that cognitive training using complex tasks, such as video games, leisure activities, or practicing a series of cognitive tasks, has shown promising results regarding transfer to a number of cognitive functions. These studies, however, do not allow direct inference about the underlying functions targeted by these training regimes. Custom-designed serious games allow to design training regimes according to specific cognitive functions and a target population's need. In the second part, we introduce the serious game Hotel Plastisse as an iPad-based training tool for older adults that allows the comparison of the simultaneous training of spatial navigation, visuomotor function, and inhibition to the training of each of these functions separately. Hotel Plastisse not only defines the cognitive functions of the multi-domain training clearly, but also implements training in an interesting learning environment including adaptive difficulty and feedback. We propose this novel training tool with the goal of furthering our understanding of how training regimes should be designed in order to affect cognitive functioning of older adults most broadly. PMID:26257643

  2. Multi-domain training in healthy old age: Hotel Plastisse as an iPad-based serious game to systematically compare multi-domain and single-domain training.

    PubMed

    Binder, Julia C; Zöllig, Jacqueline; Eschen, Anne; Mérillat, Susan; Röcke, Christina; Schoch, Sarah F; Jäncke, Lutz; Martin, Mike

    2015-01-01

    Finding effective training interventions for declining cognitive abilities in healthy aging is of great relevance, especially in view of the demographic development. Since it is assumed that transfer from the trained to untrained domains is more likely to occur when training conditions and transfer measures share a common underlying process, multi-domain training of several cognitive functions should increase the likelihood of such an overlap. In the first part, we give an overview of the literature showing that cognitive training using complex tasks, such as video games, leisure activities, or practicing a series of cognitive tasks, has shown promising results regarding transfer to a number of cognitive functions. These studies, however, do not allow direct inference about the underlying functions targeted by these training regimes. Custom-designed serious games allow to design training regimes according to specific cognitive functions and a target population's need. In the second part, we introduce the serious game Hotel Plastisse as an iPad-based training tool for older adults that allows the comparison of the simultaneous training of spatial navigation, visuomotor function, and inhibition to the training of each of these functions separately. Hotel Plastisse not only defines the cognitive functions of the multi-domain training clearly, but also implements training in an interesting learning environment including adaptive difficulty and feedback. We propose this novel training tool with the goal of furthering our understanding of how training regimes should be designed in order to affect cognitive functioning of older adults most broadly.

  3. Characteristics and pharmacological regulation of epithelial Na+ channel (ENaC) and epithelial Na+ transport.

    PubMed

    Marunaka, Yoshinori

    2014-01-01

    Epithelial Na(+) transport participates in control of various body functions and conditions: e.g., homeostasis of body fluid content influencing blood pressure, control of amounts of fluids covering the apical surface of alveolar epithelial cells at appropriate levels for normal gas exchange, and prevention of bacterial/viral infection. Epithelial Na(+) transport via the transcellular pathway is mediated by the entry step of Na(+) across the apical membrane via Epithelial Na(+) Channel (ENaC) located at the apical membrane, and the extrusion step of Na(+) across the basolateral membrane via the Na(+),K(+)-ATPase located at the basolateral membrane. The rate-limiting step of the epithelial Na(+) transport via the transcellular pathway is generally recognized to be the entry step of Na(+) across the apical membrane via ENaC. Thus, up-/down-regulation of ENaC essentially participates in regulatory systems of blood pressure and normal gas exchange. Amount of ENaC-mediated Na(+) transport is determined by the number of ENaCs located at the apical membrane, activity (open probability) of individual ENaC located at the apical membrane, single channel conductance of ENaC located at the apical membrane, and driving force for the Na(+) entry via ENaCs across the apical membrane. In the present review article, I discuss the characteristics of ENaC and how these factors are regulated.

  4. Glutathionylation-Dependence of Na(+)-K(+)-Pump Currents Can Mimic Reduced Subsarcolemmal Na(+) Diffusion.

    PubMed

    Garcia, Alvaro; Liu, Chia-Chi; Cornelius, Flemming; Clarke, Ronald J; Rasmussen, Helge H

    2016-03-08

    The existence of a subsarcolemmal space with restricted diffusion for Na(+) in cardiac myocytes has been inferred from a transient peak electrogenic Na(+)-K(+) pump current beyond steady state on reexposure of myocytes to K(+) after a period of exposure to K(+)-free extracellular solution. The transient peak current is attributed to enhanced electrogenic pumping of Na(+) that accumulated in the diffusion-restricted space during pump inhibition in K(+)-free extracellular solution. However, there are no known physical barriers that account for such restricted Na(+) diffusion, and we examined if changes of activity of the Na(+)-K(+) pump itself cause the transient peak current. Reexposure to K(+) reproduced a transient current beyond steady state in voltage-clamped ventricular myocytes as reported by others. Persistence of it when the Na(+) concentration in patch pipette solutions perfusing the intracellular compartment was high and elimination of it with K(+)-free pipette solution could not be reconciled with restricted subsarcolemmal Na(+) diffusion. The pattern of the transient current early after pump activation was dependent on transmembrane Na(+)- and K(+) concentration gradients suggesting the currents were related to the conformational poise imposed on the pump. We examined if the currents might be accounted for by changes in glutathionylation of the β1 Na(+)-K(+) pump subunit, a reversible oxidative modification that inhibits the pump. Susceptibility of the β1 subunit to glutathionylation depends on the conformational poise of the Na(+)-K(+) pump, and glutathionylation with the pump stabilized in conformations equivalent to those expected to be imposed on voltage-clamped myocytes supported this hypothesis. So did elimination of the transient K(+)-induced peak Na(+)-K(+) pump current when we included glutaredoxin 1 in patch pipette solutions to reverse glutathionylation. We conclude that transient K(+)-induced peak Na(+)-K(+) pump current reflects the effect

  5. Interaction between Na+ and H+ ions on Na-H exchange in sheep cardiac Purkinje fibers.

    PubMed

    Wu, M L; Vaughan-Jones, R D

    1997-04-01

    The interaction between Na+ and H+ ions upon Na-H exchange (NHE) was examined in sheep cardiac Purkinje fibers. Acid equivalent fluxes through NHE were examined using recordings of intracellular pH and Na+ in isolated preparations measured with ion selective microelectrodes. The extent of acid-extrusion by NHE was estimated from pH(i) recovery-rate, multiplied by beta(i) (intracellular buffering power) in response to an internal acid load induced by 20 mm NH4Cl removal (nominally HCO3- free media). A mixed inhibitory effect was found of extracellular H+ on external Na+-activation of NHE (i.e. an increase, at low pH(o), in the apparent Michaelis constant for external Na+ ions [K(Nao)(0.5)] and a decrease in the maximum transport rate [V(Nao)(max)]). In addition, we confirmed that the stoichiometry of Na(o) binding is unaffected by the pH(o) (between 7.5 and 6.5), showing a Hill coefficient close to one. The interaction between Na+ and H+ ions at the internal face of the cardiac NHE was also studied. Our evidence suggests that an increase in the intracellular Na+ ion concentration ([Na+]i) inhibits acid efflux and that this inhibition can be approximated by the decrease in thermodynamic driving force caused by reducing the transmembrane Na+ gradient. It appears, however, that small variations in [Na+]i from the normal resting level (intracellular sodium activity, a(i)Na = 7 to 13 mm) have little or no effect on acid efflux, suggesting that variation of a(i)Na is not a physiologically important controller of NHE activity in heart.

  6. Single Room Occupancy (SRO) hotels as mental health risk environments among impoverished women: the intersection of policy, drug use, trauma, and urban space

    PubMed Central

    Knight, Knight R.; Lopez, Andrea M.; Comfort, Megan; Shumway, Martha; Cohen, Jennifer; Riley, Elise

    2014-01-01

    Due to the significantly high levels of comorbid substance use and mental health diagnosis among urban poor populations, examining the intersection of drug policy and place requires a consideration of the role of housing in drug user mental health. In San Francisco, geographic boundedness and progressive health and housing polices have coalesced to make single room occupancy hotels (SROs) a key urban built environment used to house poor populations with co-occurring drug use and mental health issues. Unstably housed women who use illicit drugs have high rates of lifetime and current trauma, which manifests in disproportionately high rates of post-traumatic stress disorder (PTSD), anxiety, and depression when compared to stably housed women. We report data from a qualitative interview study (n=30) and four years of ethnography conducted with housing policy makers and unstably housed women who use drugs and live in SROs. Women in the study lived in a range of SRO built environments, from publicly-funded, newly built SROs to privately-owned, dilapidated buildings, which presented a rich opportunity for ethnographic comparison. Applying Rhodes et al.’s framework of socio-structural vulnerability, we explore how SROs can operate as “mental health risk environments” in which macro-structural factors (housing policies shaping the built environment) interact with meso-level factors (social relations within SROs) and micro-level, behavioral coping strategies to impact women’s mental health. The degree to which SRO built environments were “trauma-sensitive” at the macro level significantly influenced women’s mental health at meso- and micro- levels. Women who were living in SROs which exacerbated fear and anxiety attempted, with limited success, to deploy strategies on the meso- and micro- level to manage their mental health symptoms. Study findings underscore the importance of housing polices which consider substance use in the context of current and

  7. Prediction of human observer performance in a 2-alternative forced choice low-contrast detection task using channelized Hotelling observer: Impact of radiation dose and reconstruction algorithms

    SciTech Connect

    Yu Lifeng; Leng Shuai; Chen Lingyun; Kofler, James M.; McCollough, Cynthia H.; Carter, Rickey E.

    2013-04-15

    Purpose: Efficient optimization of CT protocols demands a quantitative approach to predicting human observer performance on specific tasks at various scan and reconstruction settings. The goal of this work was to investigate how well a channelized Hotelling observer (CHO) can predict human observer performance on 2-alternative forced choice (2AFC) lesion-detection tasks at various dose levels and two different reconstruction algorithms: a filtered-backprojection (FBP) and an iterative reconstruction (IR) method. Methods: A 35 Multiplication-Sign 26 cm{sup 2} torso-shaped phantom filled with water was used to simulate an average-sized patient. Three rods with different diameters (small: 3 mm; medium: 5 mm; large: 9 mm) were placed in the center region of the phantom to simulate small, medium, and large lesions. The contrast relative to background was -15 HU at 120 kV. The phantom was scanned 100 times using automatic exposure control each at 60, 120, 240, 360, and 480 quality reference mAs on a 128-slice scanner. After removing the three rods, the water phantom was again scanned 100 times to provide signal-absent background images at the exact same locations. By extracting regions of interest around the three rods and on the signal-absent images, the authors generated 21 2AFC studies. Each 2AFC study had 100 trials, with each trial consisting of a signal-present image and a signal-absent image side-by-side in randomized order. In total, 2100 trials were presented to both the model and human observers. Four medical physicists acted as human observers. For the model observer, the authors used a CHO with Gabor channels, which involves six channel passbands, five orientations, and two phases, leading to a total of 60 channels. The performance predicted by the CHO was compared with that obtained by four medical physicists at each 2AFC study. Results: The human and model observers were highly correlated at each dose level for each lesion size for both FBP and IR. The

  8. Evaluation of the channelized Hotelling observer with an internal-noise model in a train-test paradigm for cardiac SPECT defect detection

    NASA Astrophysics Data System (ADS)

    Brankov, Jovan G.

    2013-10-01

    The channelized Hotelling observer (CHO) has become a widely used approach for evaluating medical image quality, acting as a surrogate for human observers in early-stage research on assessment and optimization of imaging devices and algorithms. The CHO is typically used to measure lesion detectability. Its popularity stems from experiments showing that the CHO's detection performance can correlate well with that of human observers. In some cases, CHO performance overestimates human performance; to counteract this effect, an internal-noise model is introduced, which allows the CHO to be tuned to match human-observer performance. Typically, this tuning is achieved using example data obtained from human observers. We argue that this internal-noise tuning step is essentially a model training exercise; therefore, just as in supervised learning, it is essential to test the CHO with an internal-noise model on a set of data that is distinct from that used to tune (train) the model. Furthermore, we argue that, if the CHO is to provide useful insights about new imaging algorithms or devices, the test data should reflect such potential differences from the training data; it is not sufficient simply to use new noise realizations of the same imaging method. Motivated by these considerations, the novelty of this paper is the use of new model selection criteria to evaluate ten established internal-noise models, utilizing four different channel models, in a train-test approach. Though not the focus of the paper, a new internal-noise model is also proposed that outperformed the ten established models in the cases tested. The results, using cardiac perfusion SPECT data, show that the proposed train-test approach is necessary, as judged by the newly proposed model selection criteria, to avoid spurious conclusions. The results also demonstrate that, in some models, the optimal internal-noise parameter is very sensitive to the choice of training data; therefore, these models are prone

  9. Evaluation of the channelized Hotelling observer with an internal-noise model in a train-test paradigm for cardiac SPECT defect detection.

    PubMed

    Brankov, Jovan G

    2013-10-21

    The channelized Hotelling observer (CHO) has become a widely used approach for evaluating medical image quality, acting as a surrogate for human observers in early-stage research on assessment and optimization of imaging devices and algorithms. The CHO is typically used to measure lesion detectability. Its popularity stems from experiments showing that the CHO's detection performance can correlate well with that of human observers. In some cases, CHO performance overestimates human performance; to counteract this effect, an internal-noise model is introduced, which allows the CHO to be tuned to match human-observer performance. Typically, this tuning is achieved using example data obtained from human observers. We argue that this internal-noise tuning step is essentially a model training exercise; therefore, just as in supervised learning, it is essential to test the CHO with an internal-noise model on a set of data that is distinct from that used to tune (train) the model. Furthermore, we argue that, if the CHO is to provide useful insights about new imaging algorithms or devices, the test data should reflect such potential differences from the training data; it is not sufficient simply to use new noise realizations of the same imaging method. Motivated by these considerations, the novelty of this paper is the use of new model selection criteria to evaluate ten established internal-noise models, utilizing four different channel models, in a train-test approach. Though not the focus of the paper, a new internal-noise model is also proposed that outperformed the ten established models in the cases tested. The results, using cardiac perfusion SPECT data, show that the proposed train-test approach is necessary, as judged by the newly proposed model selection criteria, to avoid spurious conclusions. The results also demonstrate that, in some models, the optimal internal-noise parameter is very sensitive to the choice of training data; therefore, these models are prone

  10. Thermodynamic Model for the Solubility of Cr(OH)(3)(am) in Concentrated NaOH and NaOH-NaNO3 Solutions

    SciTech Connect

    Rai, Dhanpat ); Hess, Nancy J. ); Rao, Linfeng; Zhang, Zhicheng; Felmy, Andrew R. ); Moore, Dean A. ); Clark, Sue B.; Lumetta, Gregg J. )

    2001-12-01

    The objectives of this study were to develop a reliable thermodynamic model for predicting Cr(III) behavior in concentrated NaOH and in mixed NaOH-NaNO3 solutions for application to effective caustic leaching strategies for high-level tank sludges. To meet these objectives, the solubility of Cr(OH)3(am) was measured in 0.003 to 10.5 m NaOH, 3.0 m es in NaOH concentration...

  11. Hydrogen-fluorine exchange in NaBH4-NaBF4.

    PubMed

    Rude, L H; Filsø, U; D'Anna, V; Spyratou, A; Richter, B; Hino, S; Zavorotynska, O; Baricco, M; Sørby, M H; Hauback, B C; Hagemann, H; Besenbacher, F; Skibsted, J; Jensen, T R

    2013-11-07

    Hydrogen-fluorine exchange in the NaBH4-NaBF4 system is investigated using a range of experimental methods combined with DFT calculations and a possible mechanism for the reactions is proposed. Fluorine substitution is observed using in situ synchrotron radiation powder X-ray diffraction (SR-PXD) as a new Rock salt type compound with idealized composition NaBF2H2 in the temperature range T = 200 to 215 °C. Combined use of solid-state (19)F MAS NMR, FT-IR and DFT calculations supports the formation of a BF2H2(-) complex ion, reproducing the observation of a (19)F chemical shift at -144.2 ppm, which is different from that of NaBF4 at -159.2 ppm, along with the new absorption bands observed in the IR spectra. After further heating, the fluorine substituted compound becomes X-ray amorphous and decomposes to NaF at ~310 °C. This work shows that fluorine-substituted borohydrides tend to decompose to more stable compounds, e.g. NaF and BF3 or amorphous products such as closo-boranes, e.g. Na2B12H12. The NaBH4-NaBF4 composite decomposes at lower temperatures (300 °C) compared to NaBH4 (476 °C), as observed by thermogravimetric analysis. NaBH4-NaBF4 (1:0.5) preserves 30% of the hydrogen storage capacity after three hydrogen release and uptake cycles compared to 8% for NaBH4 as measured using Sievert's method under identical conditions, but more than 50% using prolonged hydrogen absorption time. The reversible hydrogen storage capacity tends to decrease possibly due to the formation of NaF and Na2B12H12. On the other hand, the additive sodium fluoride appears to facilitate hydrogen uptake, prevent foaming, phase segregation and loss of material from the sample container for samples of NaBH4-NaF.

  12. Deliquescence of NaCl-NaNO3, KNO3-NaNO3, and NaCl-KNO3 Salt Mixtures From 90 to 120?C

    SciTech Connect

    Carroll, S A; Craig, L; Wolery, T J

    2004-10-20

    We conducted reversed deliquescence experiments in saturated NaCl-NaNO{sub 3}-H{sub 2}O, KNO{sub 3}-NaNO{sub 3}-H{sub 2}O, and NaCl-KNO{sub 3}-H{sub 2}O systems from 90 to 120 C as a function of relative humidity and solution composition. NaCl, NaNO{sub 3}, and KNO{sub 3} represent members of dust salt assemblages that are likely to deliquesce and form concentrated brines on high-level radioactive waste package surfaces in a repository environment at Yucca Mountain, NV, USA. Discrepancy between model prediction and experimental code can be as high as 8% for relative humidity and 50% for dissolved ion concentration. The discrepancy is attributed primarily to the use of 25 C models for Cl-NO{sub 3} and K-NO{sub 3} ion interactions in the current Yucca Mountain Project high-temperature Pitzer model to describe the non-ideal behavior of these highly concentrated solutions.

  13. Vascular contractile reactivity in hypotension due to reduced renal reabsorption of Na(+) and restricted dietary Na().

    PubMed

    Alshahrani, Saeed; Rapoport, Robert M; Soleimani, Manoocher

    2017-03-01

    Reduced renal Na(+) reabsorption along with restricted dietary Na(+) depletes intravascular plasma volume which can then result in hypotension. Whether hypotension occurs and the magnitude of hypotension depends in part on compensatory angiotensin II-mediated increased vascular resistance. We investigated whether the ability of vascular resistance to mitigate the hypotension was compromised by decreased contractile reactivity. In vitro reactivity was investigated in aorta from mouse models of reduced renal Na(+) reabsorption and restricted dietary Na(+) associated with considerable hypotension and renin-angiotensin system activation: (1) the Na(+)-Cl(-)-Co-transporter (NCC) knockout (KO) with Na(+) restricted diet (0.1%, 2 weeks) and (2) the relatively more severe pendrin (apical chloride/bicarbonate exchanger) and NCC double KO. Contractile sensitivity to KCl, phenylephrine, and/or U46619 remained unaltered in aorta from both models. Maximal KCl and phenylephrine contraction expressed as force/aorta length from NCC KO with Na(+)-restricted diet remained unaltered, while in pendrin/NCC double KO were reduced to 49 and 64%, respectively. Wet weight of aorta from NCC KO with Na(+)-restricted diet remained unaltered, while pendrin/NCC double KO was reduced to 67%, consistent with decreased medial width determined with Verhoeff-Van Gieson stain. These findings suggest that hypotension associated with severe intravascular volume depletion, as the result of decreased renal Na(+) reabsorption, may in part be due to decreased contractile reactivity as a consequence of reduced vascular hypertrophy.

  14. Glutamate Water Gates in the Ion Binding Pocket of Na(+) Bound Na(+), K(+)-ATPase.

    PubMed

    Han, Minwoo; Kopec, Wojciech; Solov'yov, Ilia A; Khandelia, Himanshu

    2017-01-13

    The dynamically changing protonation states of the six acidic amino acid residues in the ion binding pocket of the Na(+), K(+) -ATPase (NKA) during the ion transport cycle are proposed to drive ion binding, release and possibly determine Na(+) or K(+) selectivity. We use molecular dynamics (MD) and density functional theory (DFT) simulations to determine the protonation scheme of the Na(+) bound conformation of NKA. MD simulations of all possible protonation schemes show that the bound Na(+) ions are most stably bound when three or four protons reside in the binding sites, and that Glu954 in site III is always protonated. Glutamic acid residues in the three binding sites act as water gates, and their deprotonation triggers water entry to the binding sites. From DFT calculations of Na(+) binding energies, we conclude that three protons in the binding site are needed to effectively bind Na(+) from water and four are needed to release them in the next step. Protonation of Asp926 in site III will induce Na(+) release, and Glu327, Glu954 and Glu779 are all likely to be protonated in the Na(+) bound occluded conformation. Our data provides key insights into the role of protons in the Na(+) binding and release mechanism of NKA.

  15. Anion-coupled Na efflux mediated by the human red blood cell Na/K pump

    PubMed Central

    1990-01-01

    The red cell Na/K pump is known to continue to extrude Na when both Na and K are removed from the external medium. Because this ouabain- sensitive flux occurs in the absence of an exchangeable cation, it is referred to as uncoupled Na efflux. This flux is also known to be inhibited by 5 mM Nao but to a lesser extent than that inhibitable by ouabain. Uncoupled Na efflux via the Na/K pump therefore can be divided into a Nao-sensitive and Nao-insensitive component. We used DIDS- treated, SO4-equilibrated human red blood cells suspended in HEPES- buffered (pHo 7.4) MgSO4 or (Tris)2SO4, in which we measured 22Na efflux, 35SO4 efflux, and changes in the membrane potential with the fluorescent dye, diS-C3 (5). A principal finding is that uncoupled Na efflux occurs electroneurally, in contrast to the pump's normal electrogenic operation when exchanging Nai for Ko. This electroneutral uncoupled efflux of Na was found to be balanced by an efflux of cellular anions. (We were unable to detect any ouabain-sensitive uptake of protons, measured in an unbuffered medium at pH 7.4 with a Radiometer pH-STAT.) The Nao-sensitive efflux of Nai was found to be 1.95 +/- 0.10 times the Nao-sensitive efflux of (SO4)i, indicating that the stoichiometry of this cotransport is two Na+ per SO4=, accounting for 60-80% of the electroneutral Na efflux. The remainder portion, that is, the ouabain-sensitive Nao-insensitive component, has been identified as PO4-coupled Na transport and is the subject of a separate paper. That uncoupled Na efflux occurs as a cotransport with anions is supported by the result, obtained with resealed ghosts, that when internal and external SO4 was substituted by the impermeant anion, tartrate i,o, the efflux of Na was inhibited 60-80%. This inhibition could be relieved by the inclusion, before DIDS treatment, of 5 mM Cli,o. Addition of 10 mM Ko to tartrate i,o ghosts, with or without Cli,o, resulted in full activation of Na/K exchange and the pump's electrogenicity

  16. Glutamate Water Gates in the Ion Binding Pocket of Na+ Bound Na+, K+-ATPase

    PubMed Central

    Han, Minwoo; Kopec, Wojciech; Solov’yov, Ilia A.; Khandelia, Himanshu

    2017-01-01

    The dynamically changing protonation states of the six acidic amino acid residues in the ion binding pocket of the Na+, K+ -ATPase (NKA) during the ion transport cycle are proposed to drive ion binding, release and possibly determine Na+ or K+ selectivity. We use molecular dynamics (MD) and density functional theory (DFT) simulations to determine the protonation scheme of the Na+ bound conformation of NKA. MD simulations of all possible protonation schemes show that the bound Na+ ions are most stably bound when three or four protons reside in the binding sites, and that Glu954 in site III is always protonated. Glutamic acid residues in the three binding sites act as water gates, and their deprotonation triggers water entry to the binding sites. From DFT calculations of Na+ binding energies, we conclude that three protons in the binding site are needed to effectively bind Na+ from water and four are needed to release them in the next step. Protonation of Asp926 in site III will induce Na+ release, and Glu327, Glu954 and Glu779 are all likely to be protonated in the Na+ bound occluded conformation. Our data provides key insights into the role of protons in the Na+ binding and release mechanism of NKA. PMID:28084301

  17. Stoichiometry and Na+ binding cooperativity of rat and flounder renal type II Na+-Pi cotransporters.

    PubMed

    Forster, I C; Loo, D D; Eskandari, S

    1999-04-01

    The stoichiometry of the rat and flounder isoforms of the renal type II sodium-phosphate (Na+-Pi) cotransporter was determined directly by simultaneous measurements of phosphate (Pi)-induced inward current and uptake of radiolabeled Pi and Na+ in Xenopus laevis oocytes expressing the cotransporters. There was a direct correlation between the Pi-induced inward charge and Pi uptake into the oocytes; the slope indicated that one net inward charge was transported per Pi. There was also a direct correlation between the Pi-induced inward charge and Na+ influx; the slope indicated that the influx of three Na+ ions resulted in one net inward charge. This behavior was similar for both isoforms. We conclude that for both Na+-Pi cotransporter isoforms the Na+:Pi stoichiometry is 3:1 and that divalent Pi is the transported substrate. Steady-state activation of the currents showed that the Hill coefficients for Pi were unity for both isoforms, whereas for Na+, they were 1.8 (flounder) and 2.5 (rat). Therefore, despite significant differences in the apparent Na+ binding cooperativity, the estimated Na+:Pi stoichiometry was the same for both isoforms.

  18. Theoretical study of Na-atom emission from NaCl (100) surfaces

    NASA Astrophysics Data System (ADS)

    Puchin, Vladimir; Shluger, Alexander; Nakai, Yasuo; Itoh, Noriaki

    1994-04-01

    Several models for the elementary processes causing the emission of alkali atoms by electronic excitation of NaCl (100) surfaces have been investigated theoretically. First, the desorption of a Na atom neighboring an electronically excited F center on the surface is simulated using a quantum-mechanical embedded-cluster technique. It is shown that emission of a Na atom is energetically favorable. The kinetics of this process is shown to be controlled by the probability of a nonradiative transition between the two states: the excited state of the F center and that corresponding to a Na atom desorbing from the surface. The potential barrier for desorption of an excited Na atom from the excited F-center state is found to be 2.1 eV. It is also found that the energy for emission of a Na atom from a cluster of F centers (the F3 center) is considerably reduced (for a certain configuration of the defect) with respect to the similar energy for a single F center. The energy barrier for emission of a Na atom neighboring an F' center on the surface is calculated to be 1 eV. It is shown that the electronic excitation of kinklike sites, with a Na atom at the edge, can lead to a barrierless emission of a Na atom, leaving a Vk-type defect behind. The results of calculations are discussed critically on the basis of existing experimental data.

  19. Influence of sodium halides (NaF, NaCl, NaBr, NaI) on the photocatalytic performance of hydrothermally synthesized hematite photoanodes.

    PubMed

    Wang, Tsinghai; Huang, Mao-Chia; Hsieh, Yi-Kong; Chang, Wen-Sheng; Lin, Jing-Chie; Lee, Chih-Hao; Wang, Chu-Fang

    2013-08-28

    It has been suggested that a high concentration of Fe(3+) in solution, a low pH, and noncomplexing ions of high ionic strength are all essential for developing a high-quality hematite array. Our curiosity was piqued regarding the role of the electrolyte ions in the hydrothermal synthesis of hematite photoanodes. In this study, we prepared hematite photoanodes hydrothermally from precursor solutions of 0.1 M FeCl3 at pH 1.55 with a background electrolyte of 1.0 M sodium halide (NaF, NaCl, NaBr, or NaI). We compared the structures and properties of the as-obtained hematite photoanodes with those of the material prepared in 1.0 M NaNO3, the most widely adopted electrolyte in previous studies. Among our studied systems, we found that the hematite photoanode prepared in NaCl solution was the only one possessing properties similar to those of the sample obtained from the NaNO3 solution-most importantly in terms of photoelectrochemical performance (ca. 0.2 mA/cm(2) with +0.4 V vs SCE). The hematites obtained from the NaF, NaBr, and NaI solutions exhibited much lower (by approximately 2 orders of magnitude) photocurrent densities under the same conditions, possibly because of their relatively less ordered crystallinity and the absence of rodlike morphologies. Because the synthetic protocol was identical in each case, we believe that these two distinct features reflect the environments in which these hematite photoanodes were formed. Consistent with the latest studies reported in the literature of the X-ray photoelectron spectra of fast-frozen hematite colloids in aqueous solutions, it appears that the degree of surface ion loading at the electrolyte-hematite interface (Stern layer) is critical during the development of hematite photoanodes. We suspect that a lower ion surface loading benefits the hematite developing relatively higher-order and a rodlike texture, thereby improving the photoelectrochemical activity.

  20. Elastic Coulomb breakup of 34Na

    NASA Astrophysics Data System (ADS)

    Singh, G.; Shubhchintak, Chatterjee, R.

    2016-08-01

    Background: 34Na is conjectured to play an important role in the production of seed nuclei in the alternate r -process paths involving light neutron rich nuclei very near the β -stability line, and as such, it is important to know its ground state properties and structure to calculate rates of the reactions it might be involved in, in the stellar plasma. Found in the region of `island of inversion', its ground state might not be in agreement with normal shell model predictions. Purpose: The aim of this paper is to study the elastic Coulomb breakup of 34Na on 208Pb to give us a core of 33Na with a neutron and in the process we try and investigate the one neutron separation energy and the ground state configuration of 34Na. Method: A fully quantum mechanical Coulomb breakup theory within the architecture of post-form finite range distorted wave Born approximation extended to include the effects of deformation is used to research the elastic Coulomb breakup of 34Na on 208Pb at 100 MeV/u. The triple differential cross section calculated for the breakup is integrated over the desired components to find the total cross-section, momentum, and angular distributions as well as the average momenta, along with the energy-angular distributions. Results: The total one neutron removal cross section is calculated to test the possible ground state configurations of 34Na. The average momentum results along with energy-angular calculations indicate 34Na to have a halo structure. The parallel momentum distributions with narrow full widths at half-maxima signify the same. Conclusion: We have attempted to analyze the possible ground state configurations of 34Na and in congruity with the patterns in the `island of inversion' conclude that even without deformation, 34Na should be a neutron halo with a predominant contribution to its ground state most probably coming from 33Na(3 /2+)⊗ 2 p3 /2ν configuration. We also surmise that it would certainly be useful and rewarding to test our

  1. The National Crisis in Education: An Appeal to the People. Report of the Proceedings of the National Citizens Conference on Education Called by the United States Commissioner of Education and Held at the Washington Hotel, Washington, D. C.. May 19, 20, 21, 1920. Bulletin, 1920, No. 29

    ERIC Educational Resources Information Center

    Bawden, William, Ed.

    1920-01-01

    This publication presents the papers presented at the Proceedings of the National Citizens Conference on Education held at the Washington Hotel, Washington last May 19-21, 1920. The purpose of the conference is to capitalize for the new era the interest in education that is springing up in all parts of the country, and to organize it for effective…

  2. Quasi-solid state rechargeable Na-CO2 batteries with reduced graphene oxide Na anodes.

    PubMed

    Hu, Xiaofei; Li, Zifan; Zhao, Yaran; Sun, Jianchao; Zhao, Qing; Wang, Jianbin; Tao, Zhanliang; Chen, Jun

    2017-02-01

    Na-CO2 batteries using earth-abundant Na and greenhouse gas CO2 are promising tools for mobile and stationary energy storage, but they still pose safety risks from leakage of liquid electrolyte and instability of the Na metal anode. These issues result in extremely harsh operating conditions of Na-CO2 batteries and increase the difficulty of scaling up this technology. We report the development of quasi-solid state Na-CO2 batteries with high safety using composite polymer electrolyte (CPE) and reduced graphene oxide (rGO) Na anodes. The CPE of PVDF-HFP [poly(vinylidene fluoride-co-hexafluoropropylene)]-4% SiO2/NaClO4-TEGDME (tetraethylene glycol dimethyl ether) has high ion conductivity (1.0 mS cm(-1)), robust toughness, a nonflammable matrix, and strong electrolyte-locking ability. In addition, the rGO-Na anode presents fast and nondendritic Na(+) plating/stripping (5.7 to 16.5 mA cm(-2)). The improved kinetics and safety enable the constructed rGO-Na/CPE/CO2 batteries to successfully cycle in wide CO2 partial pressure window (5 to 100%, simulated car exhaust) and especially to run for 400 cycles at 500 mA g(-1) with a fixed capacity of 1000 mA·hour g(-1) in pure CO2. Furthermore, we scaled up the reversible capacity to 1.1 A·hour in pouch-type batteries (20 × 20 cm, 10 g, 232 Wh kg(-1)). This study makes quasi-solid state Na-CO2 batteries an attractive prospect.

  3. Quasi–solid state rechargeable Na-CO2 batteries with reduced graphene oxide Na anodes

    PubMed Central

    Hu, Xiaofei; Li, Zifan; Zhao, Yaran; Sun, Jianchao; Zhao, Qing; Wang, Jianbin; Tao, Zhanliang; Chen, Jun

    2017-01-01

    Na-CO2 batteries using earth-abundant Na and greenhouse gas CO2 are promising tools for mobile and stationary energy storage, but they still pose safety risks from leakage of liquid electrolyte and instability of the Na metal anode. These issues result in extremely harsh operating conditions of Na-CO2 batteries and increase the difficulty of scaling up this technology. We report the development of quasi–solid state Na-CO2 batteries with high safety using composite polymer electrolyte (CPE) and reduced graphene oxide (rGO) Na anodes. The CPE of PVDF-HFP [poly(vinylidene fluoride-co-hexafluoropropylene)]–4% SiO2/NaClO4–TEGDME (tetraethylene glycol dimethyl ether) has high ion conductivity (1.0 mS cm−1), robust toughness, a nonflammable matrix, and strong electrolyte-locking ability. In addition, the rGO-Na anode presents fast and nondendritic Na+ plating/stripping (5.7 to 16.5 mA cm−2). The improved kinetics and safety enable the constructed rGO-Na/CPE/CO2 batteries to successfully cycle in wide CO2 partial pressure window (5 to 100%, simulated car exhaust) and especially to run for 400 cycles at 500 mA g−1 with a fixed capacity of 1000 mA·hour g−1 in pure CO2. Furthermore, we scaled up the reversible capacity to 1.1 A·hour in pouch-type batteries (20 × 20 cm, 10 g, 232 Wh kg−1). This study makes quasi–solid state Na-CO2 batteries an attractive prospect. PMID:28164158

  4. Electrophysiological Determination of Submembrane Na(+) Concentration in Cardiac Myocytes.

    PubMed

    Hegyi, Bence; Bányász, Tamás; Shannon, Thomas R; Chen-Izu, Ye; Izu, Leighton T

    2016-09-20

    In the heart, Na(+) is a key modulator of the action potential, Ca(2+) homeostasis, energetics, and contractility. Because Na(+) currents and cotransport fluxes depend on the Na(+) concentration in the submembrane region, it is necessary to accurately estimate the submembrane Na(+) concentration ([Na(+)]sm). Current methods using Na(+)-sensitive fluorescent indicators or Na(+) -sensitive electrodes cannot measure [Na(+)]sm. However, electrophysiology methods are ideal for measuring [Na(+)]sm. In this article, we develop patch-clamp protocols and experimental conditions to determine the upper bound of [Na(+)]sm at the peak of action potential and its lower bound at the resting state. During the cardiac cycle, the value of [Na(+)]sm is constrained within these bounds. We conducted experiments in rabbit ventricular myocytes at body temperature and found that 1) at a low pacing frequency of 0.5 Hz, the upper and lower bounds converge at 9 mM, constraining the [Na(+)]sm value to ∼9 mM; 2) at 2 Hz pacing frequency, [Na(+)]sm is bounded between 9 mM at resting state and 11.5 mM; and 3) the cells can maintain [Na(+)]sm to the above values, despite changes in the pipette Na(+) concentration, showing autoregulation of Na(+) in beating cardiomyocytes.

  5. Voltage dependence of Na translocation by the Na/K pump.

    PubMed

    Nakao, M; Gadsby, D C

    During each complete reaction cycle, the Na/K pump transports three Na ions out across the cell membrane and two K ions in. The resulting net extrusion of positive charge generates outward membrane current but, until now, it was unclear how that net charge movement occurs. Reasonable possibilities included a single positive charge moving outwards during Na translocation; or a single negative charge moving inwards during K translocation; or either positive or negative charges moving during both translocation steps, but in unequal quantities. Any step that involves net charge movement through the membrane must have voltage-dependent transition rates. Here we report measurements of transient, voltage-dependent, displacement currents generated by the pump when its normal Na/K transport cycle has been interrupted by removal of external K and it is thus constrained to carry out Na/Na exchange. The quantity and voltage sensitivity of the charge moved during these transient currents suggests that Na translocation includes a voltage-dependent transition involving movement of one positive charge across the membrane. This single step can thus fully account for the electrogenic nature of Na/K exchange. The result provides important new insight into the molecular mechanism of active cation transport.

  6. Interaction of NaCl(g) and HCl(g) with condensed NA2SO4

    NASA Technical Reports Server (NTRS)

    Stearns, C. A.; Kohl, F. J.; Fryburg, G. C.; Miller, R. A.

    1977-01-01

    The interaction of Na2SO4(l) with NaCl(g), HCl(g) and H2O(g) was studied in atmospheric pressure flowing air and oxygen at Na2SO4(l) temperatures of 900 and 1000 C. Thermomicrogravimetric and high pressure mass spectrometric sampling techniques were used. Experimental results establish that previously reported enhanced rates of weight loss of Na2SO4(l) in the presence of NaCl(g) are due to the reaction: Na2SO4(c) + 2HCl(g) = 2NaCl(g) + SO2(g) + H2O(g) + 1/2O2(g) being driven to the right in flowing gas systems. The HCl(g) is the product of hydrolysis of NaCl caused by small but significant amounts of H2O(g) present in the system. Thermochemical calculations are used to show that even with sub-ppm levels of H2O(g) present, significant quantities of HCl(g) are produced.

  7. Dynamics of Na(+)(Benzene) + Benzene Association and Ensuing Na(+)(Benzene)2* Dissociation.

    PubMed

    Paul, Amit K; Kolakkandy, Sujitha; Hase, William L

    2015-07-16

    Chemical dynamics simulations were used to study Bz + Na(+)(Bz) → Na(+)(Bz)2* association and the ensuing dissociation of the Na(+)(Bz)2* cluster (Bz = benzene). An interesting and unexpected reaction found from the simulations is direct displacement, for which the colliding Bz molecule displaces the Bz molecule attached to Na(+), forming Na(+)(Bz). The rate constant for Bz + Na(+)(Bz) association was calculated at 750 and 1000 K, and found to decrease with increase in temperature. By contrast, the direct displacement rate constant increases with temperature. The cross section and rate constant for direct displacement are approximately an order of magnitude lower than those for association. The Na(+)(Bz)2* cluster, formed by association, dissociates with a biexponential probability, with the rate constant for the short-time component approximately an order of magnitude larger than that for the longer time component. The latter rate constant agrees with that of Rice-Ramsperger-Kassel-Marcus (RRKM) theory, consistent with rapid intramolecular vibrational energy redistribution (IVR) and intrinsic RRKM dynamics for the Na(+)(Bz)2* cluster. A coupled phase space model was used to analyze the biexponential dissociation probability.

  8. Low-affinity Na+ uptake in the halophyte Suaeda maritima.

    PubMed

    Wang, Suo-Min; Zhang, Jin-Lin; Flowers, Timothy J

    2007-10-01

    Na(+) uptake by plant roots has largely been explored using species that accumulate little Na(+) into their shoots. By way of contrast, the halophyte Suaeda maritima accumulates, without injury, concentrations of the order of 400 mM NaCl in its leaves. Here we report that cAMP and Ca(2+) (blockers of nonselective cation channels) and Li(+) (a competitive inhibitor of Na(+) uptake) did not have any significant effect on the uptake of Na(+) by the halophyte S. maritima when plants were in 25 or 150 mM NaCl (150 mM NaCl is near optimal for growth). However, the inhibitors of K(+) channels, TEA(+) (10 mM), Cs(+) (3 mM), and Ba(2+) (5 mM), significantly reduced the net uptake of Na(+) from 150 mM NaCl over 48 h, by 54%, 24%, and 29%, respectively. TEA(+) (10 mM), Cs(+) (3 mM), and Ba(2+) (1 mm) also significantly reduced (22)Na(+) influx (measured over 2 min in 150 mM external NaCl) by 47%, 30%, and 31%, respectively. In contrast to the situation in 150 mm NaCl, neither TEA(+) (1-10 mM) nor Cs(+) (0.5-10 mM) significantly reduced net Na(+) uptake or (22)Na(+) influx in 25 mM NaCl. Ba(2+) (at 5 mm) did significantly decrease net Na(+) uptake (by 47%) and (22)Na(+) influx (by 36% with 1 mM Ba(2+)) in 25 mM NaCl. K(+) (10 or 50 mM) had no effect on (22)Na(+) influx at concentrations below 75 mM NaCl, but the influx of (22)Na(+) was inhibited by 50 mM K(+) when the external concentration of NaCl was above 75 mM. The data suggest that neither nonselective cation channels nor a low-affinity cation transporter are major pathways for Na(+) entry into root cells. We propose that two distinct low-affinity Na(+) uptake pathways exist in S. maritima: Pathway 1 is insensitive to TEA(+) or Cs(+), but sensitive to Ba(2+) and mediates Na(+) uptake under low salinities (25 mM NaCl); pathway 2 is sensitive to TEA(+), Cs(+), and Ba(2+) and mediates Na(+) uptake under higher external salt concentrations (150 mM NaCl). Pathway 1 might be mediated by a high-affinity K transporter

  9. Anion-coupled Na efflux mediated by the human red blood cell Na/K pump

    SciTech Connect

    Dissing, S.; Hoffman, J.F. )

    1990-07-01

    The red cell Na/K pump is known to continue to extrude Na when both Na and K are removed from the external medium. Because this ouabain-sensitive flux occurs in the absence of an exchangeable cation, it is referred to as uncoupled Na efflux. This flux is also known to be inhibited by 5 mM Nao but to a lesser extent than that inhibitable by ouabain. Uncoupled Na efflux via the Na/K pump therefore can be divided into a Nao-sensitive and Nao-insensitive component. We used DIDS-treated, SO4-equilibrated human red blood cells suspended in HEPES-buffered (pHo 7.4) MgSO4 or (Tris)2SO4, in which we measured 22Na efflux, 35SO4 efflux, and changes in the membrane potential with the fluorescent dye, diS-C3 (5). A principal finding is that uncoupled Na efflux occurs electroneurally, in contrast to the pump's normal electrogenic operation when exchanging Nai for Ko. This electroneutral uncoupled efflux of Na was found to be balanced by an efflux of cellular anions. (We were unable to detect any ouabain-sensitive uptake of protons, measured in an unbuffered medium at pH 7.4 with a Radiometer pH-STAT.) The Nao-sensitive efflux of Nai was found to be 1.95 +/- 0.10 times the Nao-sensitive efflux of (SO4)i, indicating that the stoichiometry of this cotransport is two Na+ per SO4=, accounting for 60-80% of the electroneutral Na efflux. The remainder portion, that is, the ouabain-sensitive Nao-insensitive component, has been identified as PO4-coupled Na transport and is the subject of a separate paper. That uncoupled Na efflux occurs as a cotransport with anions is supported by the result, obtained with resealed ghosts, that when internal and external SO4 was substituted by the impermeant anion, tartrate i,o, the efflux of Na was inhibited 60-80%. This inhibition could be relieved by the inclusion, before DIDS treatment, of 5 mM Cli,o.

  10. A thermochemical explanation for the stability of NaCl3 and NaCl7

    NASA Astrophysics Data System (ADS)

    Fernandes de Farias, Robson

    2017-03-01

    Thermodynamically stable cubic and orthorhombic NaCl3 as well as NaCl7 have been synthesized (Zhang et al., 2013). In the present work, a thermochemical explanation for the stability of such unusual sodium chlorides is provided, based on lattice energy values. Using the Glasser-Jenkins generalized equation (Glasser and Jenkins, 2000) lattice energies (kJ mol-1) of -162.5, -168.9 and -113.1 are calculated for Pm3n NaCl3, Pnma NaCl3 and NaCl7, respectively. It is postulated that any NaxCly compound could be synthesized, if the ionic character of the Nasbnd Cl bond in the prepared compound remains around 80%, and the sodium charge below unit.

  11. Changes in Intracellular Na+ following Enhancement of Late Na+ Current in Virtual Human Ventricular Myocytes.

    PubMed

    Cardona, Karen; Trenor, Beatriz; Giles, Wayne R

    2016-01-01

    The slowly inactivating or late Na+ current, INa-L, can contribute to the initiation of both atrial and ventricular rhythm disturbances in the human heart. However, the cellular and molecular mechanisms that underlie these pro-arrhythmic influences are not fully understood. At present, the major working hypothesis is that the Na+ influx corresponding to INa-L significantly increases intracellular Na+, [Na+]i; and the resulting reduction in the electrochemical driving force for Na+ reduces and (may reverse) Na+/Ca2+ exchange. These changes increase intracellular Ca2+, [Ca2+]i; which may further enhance INa-L due to calmodulin-dependent phosphorylation of the Na+ channels. This paper is based on mathematical simulations using the O'Hara et al (2011) model of baseline or healthy human ventricular action potential waveforms(s) and its [Ca2+]i homeostasis mechanisms. Somewhat surprisingly, our results reveal only very small changes (≤ 1.5 mM) in [Na+]i even when INa-L is increased 5-fold and steady-state stimulation rate is approximately 2 times the normal human heart rate (i.e. 2 Hz). Previous work done using well-established models of the rabbit and human ventricular action potential in heart failure settings also reported little or no change in [Na+]i when INa-L was increased. Based on our simulations, the major short-term effect of markedly augmenting INa-L is a significant prolongation of the action potential and an associated increase in the likelihood of reactivation of the L-type Ca2+ current, ICa-L. Furthermore, this action potential prolongation does not contribute to [Na+]i increase.

  12. Changes in Intracellular Na+ following Enhancement of Late Na+ Current in Virtual Human Ventricular Myocytes

    PubMed Central

    Giles, Wayne R.

    2016-01-01

    The slowly inactivating or late Na+ current, INa-L, can contribute to the initiation of both atrial and ventricular rhythm disturbances in the human heart. However, the cellular and molecular mechanisms that underlie these pro-arrhythmic influences are not fully understood. At present, the major working hypothesis is that the Na+ influx corresponding to INa-L significantly increases intracellular Na+, [Na+]i; and the resulting reduction in the electrochemical driving force for Na+ reduces and (may reverse) Na+/Ca2+ exchange. These changes increase intracellular Ca2+, [Ca2+]i; which may further enhance INa-L due to calmodulin-dependent phosphorylation of the Na+ channels. This paper is based on mathematical simulations using the O’Hara et al (2011) model of baseline or healthy human ventricular action potential waveforms(s) and its [Ca2+]i homeostasis mechanisms. Somewhat surprisingly, our results reveal only very small changes (≤ 1.5 mM) in [Na+]i even when INa-L is increased 5-fold and steady-state stimulation rate is approximately 2 times the normal human heart rate (i.e. 2 Hz). Previous work done using well-established models of the rabbit and human ventricular action potential in heart failure settings also reported little or no change in [Na+]i when INa-L was increased. Based on our simulations, the major short-term effect of markedly augmenting INa-L is a significant prolongation of the action potential and an associated increase in the likelihood of reactivation of the L-type Ca2+ current, ICa-L. Furthermore, this action potential prolongation does not contribute to [Na+]i increase. PMID:27875582

  13. Targeting voltage gated sodium channels NaV1.7, Na V1.8, and Na V1.9 for treatment of pathological cough.

    PubMed

    Muroi, Yukiko; Undem, Bradley J

    2014-02-01

    Recent advances in our understanding of voltage-gated sodium channels (NaVs) lead to the rational hypothesis that drugs capable of selective blockade of NaV subtypes may be a safe and effective strategy for the treatment of unwanted cough. Among the nine NaV subtypes (NaV1.1-NaV1.9), the afferent nerves involved in initiating cough, in common with nociceptive neurons in the somatosensory system, express mainly NaV1.7, NaV1.8, and NaV1.9. Although knowledge about the effect of selectively blocking these channels on the cough reflex is limited, their biophysical properties indicate that each may contribute to the hypertussive and allotussive state that typifies subacute and chronic nonproductive cough.

  14. Intracellular [Na+], Na+ pathways, and fluid transport in cultured bovine corneal endothelial cells.

    PubMed

    Kuang, Kunyan; Li, Yansui; Yiming, Maimaiti; Sánchez, José M; Iserovich, Pavel; Cragoe, E J; Diecke, Friedrich P J; Fischbarg, Jorge

    2004-07-01

    The mechanism of fluid transport across corneal endothelium remains unclear. We examine here the relative contributions of cellular mechanisms of Na+ transport and the homeostasis of intracellular [Na+] in cultured bovine corneal endothelial cells, and the influence of ambient Na+ and HCO3- on the deturgescence of rabbit cornea. Bovine corneal endothelial cells plated on glass coverslips were incubated for 60 min with 10 microm of the fluorescent Na+ indicator SBFI precursor in HCO3- HEPES (BH) Ringer's solution. After loading, cells were placed in a perfusion chamber. Indicator fluorescence (490 nm) was determined with a Chance-Legallais time-sharing fluorometer. Its voltage output was the ratio of the emissions excited at 340 and 380 nm. For calibration, cells were treated with gramicidin D. For fluid transport measurements, rabbit corneas were mounted in a Dikstein-Maurice chamber, and stromal thickness was measured with a specular microscope. The steady-state [Na+]i in BH was 14.36+/-0.38 mM (n = mean+/-s.e.). Upon exposure to Na+ -free BH solution (choline substituted), [Na+]i decreased to 1.81+/-0.20mM (n = 19). When going from Na+ -free plus 100 microm ouabain to BH plus ouabain, [Na+]i increased to 46.17+/-2.50 (n = 6) with a half time of 1.26+/-0.04 min; if 0.1 microm phenamil plus ouabain were present, it reached only 21.78+/-1.50mm. The exponential time constants (min-1) were: 0.56+/-0.04 for the Na+ pump; 0.39+/-0.01 for the phenamil sensitive Na+ channel; and 0.17+/-0.02 for the ouabain-phenamil-insensitive pathways. In HCO3- free medium (gluconate substituted), [Na+]i was 14.03+/-0.11mM; upon changing to BH medium, it increased to 30.77+/-0.74 mm. This last [Na+]i increase was inhibited 66% by 100 microm DIDS. Using BH medium, corneal thickness remained nearly constant, increasing at a rate of only 2.9+/-0.9 microm hr-1 during 3 hr. However, stromal thickness increased drastically (swelling rate 36.1+/-2.6 microm hr-1) in corneas superfused with BH

  15. Compact clinical high-NA multiphoton endoscopy

    NASA Astrophysics Data System (ADS)

    Weinigel, Martin; Breunig, Hans Georg; Fischer, Peter; Kellner-Höfer, Marcel; Bückle, Rainer; König, Karsten

    2012-02-01

    Multiphoton imaging methods are excellent for non-invasive imaging of living tissue without any need of additional contrast agents. The increasing demand for endoscopic techniques has forced the development of multiphoton endoscopes for imaging of areas with reduced accessibility like chronic wounds. Gradient index (GRIN) lenses can miniaturize the bulky distal focusing optics of conventional tomographs to a diameter of less than 1.4 mm and a numerical aperture (NA) of 0.8. We combined a high NA clinical multiphoton endoscope with existing multiphoton tomographs like the DermaInspect® and the MPTflex® to enable the examination of wound healing processes.

  16. Sodium-difluoro(oxalato)borate (NaDFOB): a new electrolyte salt for Na-ion batteries.

    PubMed

    Chen, Juner; Huang, Zhenguo; Wang, Caiyun; Porter, Spencer; Wang, Baofeng; Lie, Wilford; Liu, Hua Kun

    2015-06-18

    A new electrolyte salt, sodium-difluoro(oxalato)borate (NaDFOB), was synthesized and studied, which enables excellent reversible capacity and high rate capability when used in Na/Na0.44MnO2 half cells. NaDFOB has excellent compatibility with various common solvents used in Na-ion batteries, in strong contrast to the solvent dependent performances of NaClO4 and NaPF6. In addition, NaDFOB possesses good stability and generates no toxic or dangerous products when exposed to air and water. All these properties demonstrate that NaDFOB could be used to prepare high performance electrolytes for emerging Na-ion batteries.

  17. Role of the Na(+)-translocating NADH:quinone oxidoreductase in voltage generation and Na(+) extrusion in Vibrio cholerae.

    PubMed

    Vorburger, Thomas; Nedielkov, Ruslan; Brosig, Alexander; Bok, Eva; Schunke, Emina; Steffen, Wojtek; Mayer, Sonja; Götz, Friedrich; Möller, Heiko M; Steuber, Julia

    2016-04-01

    For Vibrio cholerae, the coordinated import and export of Na(+) is crucial for adaptation to habitats with different osmolarities. We investigated the Na(+)-extruding branch of the sodium cycle in this human pathogen by in vivo (23)Na-NMR spectroscopy. The Na(+) extrusion activity of cells was monitored after adding glucose which stimulated respiration via the Na(+)-translocating NADH:quinone oxidoreductase (Na(+)-NQR). In a V. cholerae deletion mutant devoid of the Na(+)-NQR encoding genes (nqrA-F), rates of respiratory Na(+) extrusion were decreased by a factor of four, but the cytoplasmic Na(+) concentration was essentially unchanged. Furthermore, the mutant was impaired in formation of transmembrane voltage (ΔΨ, inside negative) and did not grow under hypoosmotic conditions at pH8.2 or above. This growth defect could be complemented by transformation with the plasmid encoded nqr operon. In an alkaline environment, Na(+)/H(+) antiporters acidify the cytoplasm at the expense of the transmembrane voltage. It is proposed that, at alkaline pH and limiting Na(+) concentrations, the Na(+)-NQR is crucial for generation of a transmembrane voltage to drive the import of H(+) by electrogenic Na(+)/H(+) antiporters. Our study provides the basis to understand the role of the Na(+)-NQR in pathogenicity of V. cholerae and other pathogens relying on this primary Na(+) pump for respiration.

  18. Electronic Polarisability of NaNO2-NaNO3 and NaOH-NaNO3 Ionic Melts and Effective Ionic Radius of OH-

    NASA Astrophysics Data System (ADS)

    Iwadate, Yasuhiko; Ohnishi, Ryosuke; Ohkubo, Takahiro

    2017-01-01

    Molar volumes and refractive indexes of molten NaNO2-NaNO3 and NaOH-NaNO3 systems were measured by dilatometry and goniometry, respectively. The molar volumes of both systems increased with increasing temperature. Refractive indexes decreased with a rise of temperature or with increasing wavelength of the incident visible light. Assuming that the electronic polarisability is inherent in an ion, the electronic polarisability of a OH- ion in the melt was estimated from the Lorentz-Lorenz equation to be 1.26×10-30 m3, being comparable with that in the crystal. The effective ionic radius of a OH- ion was evaluated from the obtained electronic polarisability to be 1.34×10-10 m, using the correlation between the third power of the ionic radius and the electronic polarisability of an ion so far reported. The effective ionic radius obtained in this work was in good agreement with that assigned by Shannon.

  19. Recent results and prospects from NA62

    NASA Astrophysics Data System (ADS)

    Bizzeti, Andrea

    2016-11-01

    A large sample of charged kaon decays in 2007 has been collected by the NA62 experiment at CERN SPS using the experimental setup of the former NA48 experiment. Its intense kaon beam provides an abundant source of tagged neutral pions in vacuum. A measurement of the electromagnetic transition form factor slope of the neutral pion from 1:05 × 106 fully reconstructed π0 Dalitz decays is presented. The obtained preliminary value a = (3.70 ± 0.53stat ± 0.36syst) × 10-2 is the first 5.8σ observation of a non-zero slope in the time-like region of momentum transfer. K+ → π+ vv¯ is a theoretically very clean decay where indirect effects of new physics may be detectable. The NA62 apparatus has been significantly upgraded between 2008 and 2014 in order to measure the branching ratio of this decay with 10% precision. The NA62 experiment took data with the new setup in pilot runs in 2014 and 2015, reaching the design beam intensity. Results of first data quality studies in view of the 2016-2017 physics runs are presented.

  20. Light-induced drift of Na atoms

    NASA Astrophysics Data System (ADS)

    Werij, H. G. C.; Woerdman, J. P.

    1988-10-01

    Light can induce a flux of optically absorbing particles immersed in a buffer gas, when these particles have a different mobility in the ground and excited state. This paper presents a study of light-induced drift (LID) of Na atoms in noble gases, which can be regarded as the “canonical” system for experiments in this field. We have experimentally studied the LID effect in the optically thin and the optically thick regimes. Parameters which have been varied are laser frequency, laser intensity, buffer gas pressure and buffer gas species. This work gives the first critical comparison of LID experiments with realistic theory in which the multilevel complications of the Na atom have been incorporated. In the optically thick case (“optical piston”) one can distinguish the open cell and the closed cell regimes. Effects of adsorption and desorption of Na atoms at the surface of the cell wall have been incorporated into the theory. The experimental data are in excellent agreement with the results of a four-level rate-equation model for LID which incorporates the fine and hyperfine structure of the level scheme of the Na absorbers.

  1. Mechanisms contributing to the cardiac inotropic effect of Na pump inhibition and reduction of extracellular Na

    PubMed Central

    1987-01-01

    Reduction of the transsarcolemmal [Na] gradient in rabbit cardiac muscle leads to an increase in the force of contraction. This has frequently been attributed to alteration of Ca movements via the sarcolemmal Na/Ca exchange system. However, the specific mechanisms that mediate the increased force at individual contractions have not been clearly established. In the present study, the [Na] gradient was decreased by reduction of extracellular [Na] or inhibition of the Na pump by either the cardioactive steroid acetylstrophanthidin or by reduction of extracellular [K]. Contractile performance and changes in extracellular Ca (sensed by double-barreled Ca-selective microelectrodes) were studied in order to elucidate the underlying basis for the increase in force. In the presence of agents that inhibit sarcoplasmic reticulum (SR) function (10 mM caffeine, 100-500 nM ryanodine), reduction of the [Na] gradient produced increases in contractile force similar to that observed in the absence of caffeine or ryanodine. It is concluded that an intact, functioning SR is not required for the inotropic effect of [Na] gradient reduction (at least in rabbit ventricle). However, this does not exclude a possible contribution of enhanced SR Ca release in the inotropic response to [Na] gradient reduction in the absence of caffeine or ryanodine. Acetylstrophanthidin (3-5 microM) usually leads to an increase in the magnitude of extracellular Ca depletions associated with individual contractions. However, acetylstrophanthidin can also increase extracellular Ca accumulation during the contraction, especially at potentiated contractions. This extracellular Ca accumulation can be suppressed by ryanodine and it is suggested that this apparent enhancement of Ca efflux is secondary to an enhanced release of Ca from the SR. Under conditions where Ca efflux during contractions is minimized (after a rest interval in the presence of ryanodine), acetylstrophanthidin increased both the rate and the

  2. Intracellular Na(+) and metabolic modulation of Na/K pump and excitability in the rat suprachiasmatic nucleus neurons.

    PubMed

    Wang, Yi-Chi; Yang, Jyh-Jeen; Huang, Rong-Chi

    2012-10-01

    Na/K pump activity and metabolic rate are both higher during the day in the suprachiasmatic nucleus (SCN) that houses the circadian clock. Here we investigated the role of intracellular Na(+) and energy metabolism in regulating Na/K pump activity and neuronal excitability. Removal of extracellular K(+) to block the Na/K pump excited SCN neurons to fire at higher rates and return to normal K(+) to reactivate the pump produced rebound hyperpolarization to inhibit firing. In the presence of tetrodotoxin to block the action potentials, both zero K(+)-induced depolarization and rebound hyperpolarization were blocked by the cardiac glycoside strophanthidin. Ratiometric Na(+) imaging with a Na(+)-sensitive fluorescent dye indicated saturating accumulation of intracellular Na(+) in response to pump blockade with zero K(+). The Na(+) ionophore monensin also induced Na(+) loading and hyperpolarized the membrane potential, with the hyperpolarizing effect of monensin abolished in zero Na(+) or by pump blockade. Conversely, Na(+) depletion with Na(+)-free pipette solution depolarized membrane potential but retained residual Na/K pump activity. Cyanide inhibition of oxidative phosphorylation blocked the Na/K pump to depolarize resting potential and increase spontaneous firing in most cells, and to raise intracellular Na(+) levels in all cells. Nonetheless, the Na/K pump was incompletely blocked by cyanide but completely blocked by iodoacetate to inhibit glycolysis, indicating the involvement of both oxidative phosphorylation and glycolysis in fueling the Na/K pump. Together, the results indicate the importance of intracellular Na(+) and energy metabolism in regulating Na/K pump activity as well as neuronal excitability in the SCN neurons.

  3. [Regulation of the Na/Ca exchanger].

    PubMed

    DiPolo, R; Rojas, H; Beaugé, L

    1993-01-01

    The introduction of the squid giant axon preparation to studies on Ca homeostasis has proven very useful in laying the foundations in the study of Ca regulation. In particular the Na/Ca exchange mechanism has been characterized in terms of its regulatory processes using the well define technique of intracellular dialysis and membrane potential control. The Na/Ca exchange countertransport system plays a critical role in physiological processes including cardiac contractility and photoreception. It has also been implicate in the etiology of essential hypertension, cardiac arrhythmias and cell death. The ability of the Na/Ca exchanger to regulate the intracellular ionized Ca concentration ([Ca2+i]) under physiological conditions, is determined by the direction (net Ca efflux or Ca influx), and magnitude of transport. The direction of Ca transport is decided by the chemical gradient of sodium and calcium. The magnitude of the exchange is regulated by kinetic factors. This kinetic factors are critical since they decide whether the exchanger will mediate a net Ca movement under certain conditions. Recently, a large effort has been put together to characterize the secondary modulation of the Na/Ca exchanger. In particular modulation by MgATP and intracellular Ca2+. In nerve cells we have discover that MgATP regulates the exchanger through as phosphorylation-dephosphorylation processes most probably relate to the action of a kinase-phosphatase system. The other important ligand that regulates the exchange activity is the level of [Ca2+i]. We have found the presence of a regulatory site in the cytoplasmic face of the exchanger different from the transport site and probably responsible for turning the carrier "on" or "off". In this article we will depict some of the processes involved in the metabolic and ionic regulation of the Na/Ca exchanger.

  4. Laser trapping of {sup 21}Na atoms

    SciTech Connect

    Lu, Zheng-Tian

    1994-09-01

    This thesis describes an experiment in which about four thousand radioactive {sup 21}Na (t{sub l/2} = 22 sec) atoms were trapped in a magneto-optical trap with laser beams. Trapped {sup 21}Na atoms can be used as a beta source in a precision measurement of the beta-asymmetry parameter of the decay of {sup 21}Na {yields} {sup 21}Ne + {Beta}{sup +} + v{sub e}, which is a promising way to search for an anomalous right-handed current coupling in charged weak interactions. Although the number o trapped atoms that we have achieved is still about two orders of magnitude lower than what is needed to conduct a measurement of the beta-asymmetry parameter at 1% of precision level, the result of this experiment proved the feasibility of trapping short-lived radioactive atoms. In this experiment, {sup 21}Na atoms were produced by bombarding {sup 24}Mg with protons of 25 MeV at the 88 in. Cyclotron of Lawrence Berkeley Laboratory. A few recently developed techniques of laser manipulation of neutral atoms were applied in this experiment. The {sup 21}Na atoms emerging from a heated oven were first transversely cooled. As a result, the on-axis atomic beam intensity was increased by a factor of 16. The atoms in the beam were then slowed down from thermal speed by applying Zeeman-tuned slowing technique, and subsequently loaded into a magneto-optical trap at the end of the slowing path. The last two chapters of this thesis present two studies on the magneto-optical trap of sodium atoms. In particular, the mechanisms of magneto-optical traps at various laser frequencies and the collisional loss mechanisms of these traps were examined.

  5. The Na4(+3) Clusters in Sodium Sodalite

    DTIC Science & Technology

    1992-05-15

    ATES COVOIN0i-15-92 Technical 06-01-91 to 05-31-92 4. TITLE ANA SUGTITLE S. RNORNG NUMBER The Na4+ 3 Clusters in Sodium Sodalite NN l14-e0-J-se59a 𔄀...3 [AlSiO 4]3 sodalite prepared by high vacuum deposition of sodium atoms. The samples with a Na 43 +:Na33+ cluster ratio up to 1:10 show a single...absorption feature with -m. = 628 nm (1.99 eV). The absorption originates from the individual sodalite cages containing Na 43+ cluster. For the Na 43+:Na

  6. The solubility of Cr(OH){sub 3}(am) in concentrated NaOH and NaOH-NaNO{sub 3} solutions

    SciTech Connect

    Felmy, A.R.; Rai, D.; Fulton, R.W.

    1994-08-01

    Chromium is a major component of the Hanford waste tank sludges, and the presence of Cr in the sludges is a significant concern in the disposal of these sludges because Cr can interfere with the formation of waste glasses. One of the current pretreatment strategies for removing constituents that can interfere with glass formation, such as P and Cr, is to wash/dissolve the sludges in basic NaOH solutions. The solubility of Cr(OH){sub 3}(am) was measured in concentrated NaOH ranging in concentration from 0.1M to 6.0M and in NaOH-NaNO{sub 3} solutions with fixed NaOH concentration and variable NaNO{sub 3} concentration at room temperature (22--23 C). Equilibrium between solids and solutions was approached relatively slowly and required approximately 60--70 days before steady-state concentrations were reached. A thermodynamic model, based upon the Pitzer equations, was developed from the solubility data in NaOH, which includes only two aqueous Cr species (Cr(OH){sub 4}{sup {minus}} and NaCr(OH){sub 4}(aq)) and ion-interaction parameters for Na{sup +} with Cr(OH){sub 4}{sup {minus}}. This model was then tested in the mixed NaOH-NaNO{sub 3} solutions and found to be reliable.

  7. Effects of non-uniform root zone salinity on water use, Na+ recirculation, and Na+ and H+ flux in cotton.

    PubMed

    Kong, Xiangqiang; Luo, Zhen; Dong, Hezhong; Eneji, A Egrinya; Li, Weijiang

    2012-03-01

    A new split-root system was established through grafting to study cotton response to non-uniform salinity. Each root half was treated with either uniform (100/100 mM) or non-uniform NaCl concentrations (0/200 and 50/150 mM). In contrast to uniform control, non-uniform salinity treatment improved plant growth and water use, with more water absorbed from the non- and low salinity side. Non-uniform treatments decreased Na(+) concentrations in leaves. The [Na(+)] in the '0' side roots of the 0/200 treatment was significantly higher than that in either side of the 0/0 control, but greatly decreased when the '0' side phloem was girdled, suggesting that the increased [Na(+)] in the '0' side roots was possibly due to transportation of foliar Na(+) to roots through phloem. Plants under non-uniform salinity extruded more Na(+) from the root than those under uniform salinity. Root Na(+) efflux in the low salinity side was greatly enhanced by the higher salinity side. NaCl-induced Na(+) efflux and H(+) influx were inhibited by amiloride and sodium orthovanadate, suggesting that root Na(+) extrusion was probably due to active Na(+)/H(+) antiport across the plasma membrane. Improved plant growth under non-uniform salinity was thus attributed to increased water use, reduced leaf Na(+) concentration, transport of excessive foliar Na(+) to the low salinity side, and enhanced Na(+) efflux from the low salinity root.

  8. Synthesis of Na-A and/or Na-X zeolite/porous carbon composites from carbonized rice husk

    NASA Astrophysics Data System (ADS)

    Katsuki, Hiroaki; Komarneni, Sridhar

    2009-07-01

    Na-A and/or Na-X zeolite/porous carbon composites were prepared under hydrothermal conditions by NaOH dissolution of silica first from carbonized rice husk followed by addition of NaAlO 2 and in situ crystallization of zeolites i.e., using a two-step process. When a one-step process was used, both Na-A and Na-X zeolites crystallized on the surface of carbon. Na-A or Na-X zeolite crystals were prepared on the porous carbonized rice husk at 90 °C for 2-6 h by changing the SiO 2/Al 2O 3, H 2O/Na 2O and Na 2O/SiO 2 molar ratios of precursors in the two-step process. The surface area and NH 4+-cation exchange capacity (CEC) of Na-A zeolite/porous carbon were found to be 171 m 2/g and 506 meq/100 g, respectively, while those of Na-X zeolite/porous carbon composites were 676 m 2/g and 317 meq/100 g, respectively. Na-A and Na-X zeolites are well-known microporous and hydrophilic materials while carbonized rice husk was found to be mesoporous (pores of ˜3.9 nm) and hydrophobic. These hybrid microporous-mesoporous and hydrophilic-hydrophobic composites are expected to be useful for decontamination of metal cations as well as organic contaminants simultaneously.

  9. Regulation of cardiac myocyte contractility by phospholemman: Na+/Ca2+ exchange versus Na+ -K+ -ATPase.

    PubMed

    Song, Jianliang; Zhang, Xue-Qian; Wang, JuFang; Cheskis, Ellina; Chan, Tung O; Feldman, Arthur M; Tucker, Amy L; Cheung, Joseph Y

    2008-10-01

    Phospholemman (PLM) regulates cardiac Na(+)/Ca(2+) exchanger (NCX1) and Na(+)-K(+)-ATPase in cardiac myocytes. PLM, when phosphorylated at Ser(68), disinhibits Na(+)-K(+)-ATPase but inhibits NCX1. PLM regulates cardiac contractility by modulating Na(+)-K(+)-ATPase and/or NCX1. In this study, we first demonstrated that adult mouse cardiac myocytes cultured for 48 h had normal surface membrane areas, t-tubules, and NCX1 and sarco(endo)plasmic reticulum Ca(2+)-ATPase levels, and retained near normal contractility, but alpha(1)-subunit of Na(+)-K(+)-ATPase was slightly decreased. Differences in contractility between myocytes isolated from wild-type (WT) and PLM knockout (KO) hearts were preserved after 48 h of culture. Infection with adenovirus expressing green fluorescent protein (GFP) did not affect contractility at 48 h. When WT PLM was overexpressed in PLM KO myocytes, contractility and cytosolic Ca(2+) concentration ([Ca(2+)](i)) transients reverted back to those observed in cultured WT myocytes. Both Na(+)-K(+)-ATPase current (I(pump)) and Na(+)/Ca(2+) exchange current (I(NaCa)) in PLM KO myocytes rescued with WT PLM were depressed compared with PLM KO myocytes. Overexpressing the PLMS68E mutant (phosphomimetic) in PLM KO myocytes resulted in the suppression of I(NaCa) but had no effect on I(pump). Contractility, [Ca(2+)](i) transient amplitudes, and sarcoplasmic reticulum Ca(2+) contents in PLM KO myocytes overexpressing the PLMS68E mutant were depressed compared with PLM KO myocytes overexpressing GFP. Overexpressing the PLMS68A mutant (mimicking unphosphorylated PLM) in PLM KO myocytes had no effect on I(NaCa) but decreased I(pump). Contractility, [Ca(2+)](i) transient amplitudes, and sarcoplasmic reticulum Ca(2+) contents in PLM KO myocytes overexpressing the S68A mutant were similar to PLM KO myocytes overexpressing GFP. We conclude that at the single-myocyte level, PLM affects cardiac contractility and [Ca(2+)](i) homeostasis primarily by its direct

  10. Na/beta-alumina/NaAlCl4, Cl2/C circulating cell

    NASA Astrophysics Data System (ADS)

    Cherng, Jing-Yih; Bennion, Douglas N.

    1987-09-01

    A study was made of a high specific energy battery based on a sodium negative electrode and a chlorine positive electrode with molten AlCl3-NaCl electrolyte and a solid beta alumina separator. The basic performance of a Na beta-alumina NaAlCl4, Cl2/C circulating cell at 200 C was demonstrated. This cell can be started at 150 C. The use of melting sodium chloroaluminate electrolyte overcomes some of the material problems associated with the high working temperatures of present molten salt systems, such as Na/S and LiAl/FeS, and retains the advantages of high energy density and relatively efficient electrode processes. Preliminary investigations were conducted on a sodium-chlorine static cell, material compability, electrode design, wetting, and theoretical calculations to assure a better chance of success before assembling a Na/Cl2 circulating cell. Mathematical models provide a theoretical explanation for the performance of the NaCl2 battery. The results of mathematical models match the experimental results very well. According to the result of the mathematical modeling, an output at 180 mA/sq cm and 3.2 V can be obtained with optimized cell design.

  11. Final-state symmetry of Na 1s core-shell excitons in NaCl and NaF

    SciTech Connect

    Nagle, K.P.; Seidler, G.T.; Shirley, E.L.; Fister, T.T.; Bradley, J.A.; Brown, F.C.

    2009-08-13

    We report measurements of the Na 1s contribution to the nonresonant inelastic x-ray scattering (NRIXS) from NaCl and NaF. Prior x-ray absorption studies have observed two pre-edge excitons in both materials. The momentum-transfer dependence (q dependence) of the measured NRIXS cross section and of real-space full multiple scattering and Bethe-Salpeter calculations determine that the higher-energy core excitons are s type for each material. The lower-energy core excitons contribute at most weakly to the NRIXS signal and we propose that these may be surface core excitons, as have been observed in several other alkali halides. The analysis of the orbital angular momentum of these features leads to a discussion of the limited sensitivity of NRIXS measurements to d-type final states when investigating 1s initial states. In this case the s- and p-type final density of states can be characterized by measurements at a small number of momentum transfers. This is in contrast to the case of more complex initial states for which measurements at a large number of momentum transfers are needed to separate the rich admixture of accessible and contributing final-state symmetries.

  12. Computational interpretation of 23Na MQMAS NMR spectra: A comprehensive investigation of the Na environment in silicate glasses

    NASA Astrophysics Data System (ADS)

    Gambuzzi, Elisa; Charpentier, Thibault; Menziani, Maria Cristina; Pedone, Alfonso

    2014-09-01

    Molecular dynamics, density functional theory calculations and 23Na NMR experiments have been used to inspect the chemical and structural characteristics of the Na environment in soda-lime silicate (CSN) and aluminosilicate (CASN) glasses. The use of an improved 3QMAS pulse sequence has allowed a clear identification of different Na sites. Average coordination numbers have been extracted by fitting the 23Na 3QMAS spectra with the computed NMR parameters. The results show that the 23Na δiso values correlate with the average <Na-O> distances only when the different coordination numbers are explicitly taken into account.

  13. Elementary immunology: Na(+) as a regulator of immunity.

    PubMed

    Schatz, Valentin; Neubert, Patrick; Schröder, Agnes; Binger, Katrina; Gebhard, Matthias; Müller, Dominik N; Luft, Friedrich C; Titze, Jens; Jantsch, Jonathan

    2017-02-01

    The skin can serve as an interstitial Na(+) reservoir. Local tissue Na(+) accumulation increases with age, inflammation and infection. This increased local Na(+) availability favors pro-inflammatory immune cell function and dampens their anti-inflammatory capacity. In this review, we summarize available data on how NaCl affects various immune cells. We particularly focus on how salt promotes pro-inflammatory macrophage and T cell function and simultaneously curtails their regulatory and anti-inflammatory potential. Overall, these findings demonstrate that local Na(+) availability is a promising novel regulator of immunity. Hence, the modulation of tissue Na(+) levels bears broad therapeutic potential: increasing local Na(+) availability may help in treating infections, while lowering tissue Na(+) levels may be used to treat, for example, autoimmune and cardiovascular diseases.

  14. Mechanisms and regulation of Na(+) uptake by freshwater fish.

    PubMed

    Kumai, Yusuke; Perry, Steve F

    2012-12-01

    Mechanisms of ion uptake by freshwater (FW) fish have received considerable attention over the past 80 years. Through an assortment of techniques incorporating whole animal physiology, electrophysiology and molecular biological approaches, three models have been proposed to account for Na(+) uptake. (1) Direct exchange of Na(+) and H(+) via one or more types of Na(+)/H(+) exchanger (slc9), (2) uptake of Na(+) through epithelial Na(+) channels energized by an electrical gradient created by H(+)-ATPase and (3) Na(+)/Cl(-) co-transport (slc12). While each mechanism is supported at least in part by theoretical or experimental data, there are several outstanding questions that have not yet been fully resolved. Furthermore, there are few details concerning how these Na(+) uptake mechanisms are fine tuned in response to the fluctuating FW environments. In this review, we summarize the current understanding of these three Na(+) uptake mechanisms and discuss their regulation by endocrine (cortisol and prolactin) and neurohumoral (catecholamines) factors.

  15. An enhancement to the NA4 gear vibration diagnostic parameter

    NASA Technical Reports Server (NTRS)

    Decker, Harry J.; Handschuh, Robert F.; Zakrajsek, James J.

    1994-01-01

    A new vibration diagnostic parameter for health monitoring of gears, NA4*, is proposed and tested. A recently developed gear vibration diagnostic parameter NA4 outperformed other fault detection methods at indicating the start and initial progression of damage. However, in some cases, as the damage progressed, the sensitivity of the NA4 and FM4 parameters tended to decrease and no longer indicated damage. A new parameter, NA4* was developed by enhancing NA4 to improve the trending of the parameter. This allows for the indication of damage both at initiation and also as the damage progresses. The NA4* parameter was verified and compared to the NA4 and FM4 parameters using experimental data from single mesh spur and spiral bevel gear fatigue rigs. The primary failure mode for the test cases was naturally occurring tooth surface pitting. The NA4* parameter is shown to be a more robust indicator of damage.

  16. U. S. EPA’S NA APPROACH FOR PETROLEUM HYDROCARBONS

    EPA Science Inventory

    Most evaluations of NA of petroleum hydrocarbons use geochemical data to document the NA through biodegradation. The expected trends during biodegradation (plume interior vs. background concentrations) are Dissolved oxygen concentrations below background, Nitrate concentrations ...

  17. Inelastic and reactive collisions with polarized excited Na atoms

    SciTech Connect

    Schmidt, H.; Hertel, I.V.; Lee, Y.T.

    1985-07-01

    Polarization effects in inelastic collisions of laser state-prepared Na(3/sup 2/P, M/sub J/) with Na/sup +/ leading to Na(3/sup 2/D) or Na(3/sup 2/S) are discussed for the energy range E/sub cm/ = 5-47.5eV. Studies with linearly polarized light can be explained with a simple ''locking'' model of the Na(P)-orbital. The investigations employing circularly polarized light are a very sensitive test of the models describing the nonadiabatic angular momentum coupling between electronic and nuclear motion. The dynamical effects of the electronic spin on the angular momentum transfer are discussed. Recent crossed-beam experiments on the Na + O/sub 2/ -> NaO = O reaction in the energy range E/sub cm/ = 0/3-0.8eV show a pronounced dependence on the electric electronic symmetry of Na. 17 refs., 11 figs.

  18. Design of Na(+) -Selective Fluorescent Probes: A Systematic Study of the Na(+) -Complex Stability and the Na(+) /K(+) Selectivity in Acetonitrile and Water.

    PubMed

    Schwarze, Thomas; Müller, Holger; Schmidt, Darya; Riemer, Janine; Holdt, Hans-Jürgen

    2017-02-14

    There is a tremendous demand for highly Na(+) -selective fluoroionophores to monitor the top analyte Na(+) in life science. Here, we report a systematic route to develop highly Na(+) /K(+) selective fluorescent probes. Thus, we synthesized a set of fluoroionophores 1, 3, 4, 5, 8 and 9 (see Scheme ) to investigate the Na(+) /K(+) selectivity and Na(+) - complex stability in CH3 CN and H2 O. These Na(+) -probes bear different 15-crown-5 moieties to bind Na(+) stronger than K(+) . In the set of the diethylaminocoumarin-substituted fluoroionophores 1-5, the following trend of fluorescence quenching 1>3>2>4>5 in CH3 CN was observed. Therefore, the flexibility of the aza-15-crown-5 moieties in 1-4 determines the conjugation of the nitrogen lone pair with the aromatic ring. As a consequence, 1 showed in CH3 CN the highest Na(+) -induced fluorescence enhancement (FE) by a factor of 46.5 and a weaker K(+) induced FE of 3.7. The Na(+) -complex stability of 1-4 in CH3 CN is enhanced in the following order of 2>4>3>1, assuming that the O-atom of the methoxy group in the ortho-position, as shown in 2, strengthened the Na(+) -complex formation. Furthermore, we found for the N-(o-methoxyphenyl)aza-15-crown-5 substituted fluoroionophores 2, 8 and 9 in H2 O, an enhanced Na(+) -complex stability in the following order 8>2>9 and an increased Na(+) /K(+) selectivity in the reverse order 9>2>8. Notably, the Na(+) -induced FE of 8 (FEF=10.9), 2 (FEF=5.0) and 9 (FEF=2.0) showed a similar trend associated with a decreased K(+) -induced FE [8 (FEF=2.7)>2 (FEF=1.5)>9 (FEF=1.1)]. Here, the Na(+) -complex stability and Na(+) /K(+) selectivity is also influenced by the fluorophore moiety. Thus, fluorescent probe 8 (Kd =48 mm) allows high-contrast, sensitive, and selective Na(+) measurements over extracellular K(+) levels. A higher Na(+) /K(+) selectivity showed fluorescent probe 9, but also a higher Kd value of 223 mm. Therefore, 9 is a suitable tool to measure Na(+) concentrations up to

  19. Na+-driven bacterial flagellar motors.

    PubMed

    Imae, Y; Atsumi, T

    1989-12-01

    Bacterial flagellar motors are the reversible rotary engine which propels the cell by rotating a helical flagellar filament as a screw propeller. The motors are embedded in the cytoplasmic membrane, and the energy for rotation is supplied by the electrochemical potential of specific ions across the membrane. Thus, the analysis of motor rotation at the molecular level is linked to an understanding of how the living system converts chemical energy into mechanical work. Based on the coupling ions, the motors are divided into two types; one is the H+-driven type found in neutrophiles such as Bacillus subtilis and Escherichia coli and the other is the Na+-driven type found in alkalophilic Bacillus and marine Vibrio. In this review, we summarize the current status of research on the rotation mechanism of the Na+-driven flagellar motors, which introduces several new aspects in the analysis.

  20. The two C-terminal tyrosines stabilize occluded Na/K pump conformations containing Na or K ions.

    PubMed

    Vedovato, Natascia; Gadsby, David C

    2010-07-01

    Interactions of the three transported Na ions with the Na/K pump remain incompletely understood. Na/K pump crystal structures show that the extended C terminus of the Na,K-adenosine triphosphatase (ATPase) alpha subunit directly contacts transmembrane helices. Deletion of the last five residues (KETYY in almost all Na/K pumps) markedly lowered the apparent affinity for Na activation of pump phosphorylation from ATP, a reflection of cytoplasmic Na affinity for forming the occluded E1P(Na3) conformation. ATPase assays further suggested that C-terminal truncations also interfere with low affinity Na interactions, which are attributable to extracellular effects. Because extracellular Na ions traverse part of the membrane's electric field to reach their binding sites in the Na/K pump, their movements generate currents that can be monitored with high resolution. We report here electrical measurements to examine how Na/K pump interactions with extracellular Na ions are influenced by C-terminal truncations. We deleted the last two (YY) or five (KESYY) residues in Xenopus laevis alpha1 Na/K pumps made ouabain resistant by either of two kinds of point mutations and measured their currents as 10-mM ouabain-sensitive currents in Xenopus oocytes after silencing endogenous Xenopus Na/K pumps with 1 microM ouabain. We found the low affinity inhibitory influence of extracellular Na on outward Na/K pump current at negative voltages to be impaired in all of the C-terminally truncated pumps. Correspondingly, voltage jump-induced transient charge movements that reflect pump interactions with extracellular Na ions were strongly shifted to more negative potentials; this signals a several-fold reduction of the apparent affinity for extracellular Na in the truncated pumps. Parallel lowering of Na affinity on both sides of the membrane argues that the C-terminal contacts provide important stabilization of the occluded E1P(Na3) conformation, regardless of the route of Na ion entry into the

  1. The NA62 experiment at CERN

    NASA Astrophysics Data System (ADS)

    Venditti, Stefano

    2016-12-01

    The goal of the NA62 experiment at CERN is to collect O(100) events of the ultrarare K+→ π +ν bar {ν } decay in two years. After a long R&D phase and a successful pilot run in 2014, the first data-taking phase took place in 2015. In this paper the importance of the experiment's physics goal, as well as the experimental solutions adopted in order to attain it, will be reviewed.

  2. The complex lightcurve of 1992 NA

    NASA Technical Reports Server (NTRS)

    Wisniewski, Wieslaw Z.; Harris, A. W.

    1994-01-01

    Amor asteroid 1992 NA was monitored during three nights at a large phase angle of -65 deg. The lightcurves obtained did not reveal a repeatable curve with two maxima and two minima. However, some features suggested a periodicity with three maxima and three minima. A satisfactory composite lightcurve of this form was obtained by means of an 'eyeball' fit and by Fourier analysis. Individual and composite lightcurves are presented. The observed colors are consistent with the C class.

  3. Spontaneous NA+ transients in individual mitochondria of intact astrocytes.

    PubMed

    Azarias, Guillaume; Van de Ville, Dimitri; Unser, Michael; Chatton, Jean-Yves

    2008-02-01

    Mitochondria in intact cells maintain low Na(+) levels despite the large electrochemical gradient favoring cation influx into the matrix. In addition, they display individual spontaneous transient depolarizations. The authors report here that individual mitochondria in living astrocytes exhibit spontaneous increases in their Na(+) concentration (Na(mit)(+) spiking), as measured using the mitochondrial probe CoroNa Red. In a field of view with approximately 30 astrocytes, up to 1,400 transients per minute were typically detected under resting conditions. Na(mit)(+) spiking was also observed in neurons, but was scarce in two nonneural cell types tested. Astrocytic Na(mit)(+) spikes averaged 12.2 +/- 0.8 s in duration and 35.5 +/- 3.2 mM in amplitude and coincided with brief mitochondrial depolarizations; they were impaired by mitochondrial depolarization and ruthenium red pointing to the involvement of a cation uniporter. Na(mit)(+) spiking activity was significantly inhibited by mitochondrial Na(+)/H(+) exchanger inhibition and sensitive to cellular pH and Na(+) concentration. Ca(2+) played a permissive role on Na(mit)(+) spiking activity. Finally, the authors present evidence suggesting that Na(mit)(+) spiking frequency was correlated with cellular ATP levels. This study shows that, under physiological conditions, individual mitochondria in living astrocytes exhibit fast Na(+) exchange across their inner membrane, which reveals a new form of highly dynamic and localized functional regulation.

  4. Glial Na(+) -dependent ion transporters in pathophysiological conditions.

    PubMed

    Boscia, Francesca; Begum, Gulnaz; Pignataro, Giuseppe; Sirabella, Rossana; Cuomo, Ornella; Casamassa, Antonella; Sun, Dandan; Annunziato, Lucio

    2016-10-01

    Sodium dynamics are essential for regulating functional processes in glial cells. Indeed, glial Na(+) signaling influences and regulates important glial activities, and plays a role in neuron-glia interaction under physiological conditions or in response to injury of the central nervous system (CNS). Emerging studies indicate that Na(+) pumps and Na(+) -dependent ion transporters in astrocytes, microglia, and oligodendrocytes regulate Na(+) homeostasis and play a fundamental role in modulating glial activities in neurological diseases. In this review, we first briefly introduced the emerging roles of each glial cell type in the pathophysiology of cerebral ischemia, Alzheimer's disease, epilepsy, Parkinson's disease, Amyotrophic Lateral Sclerosis, and myelin diseases. Then, we discussed the current knowledge on the main roles played by the different glial Na(+) -dependent ion transporters, including Na(+) /K(+) ATPase, Na(+) /Ca(2+) exchangers, Na(+) /H(+) exchangers, Na(+) -K(+) -Cl(-) cotransporters, and Na(+) - HCO3- cotransporter in the pathophysiology of the diverse CNS diseases. We highlighted their contributions in cell survival, synaptic pathology, gliotransmission, pH homeostasis, and their role in glial activation, migration, gliosis, inflammation, and tissue repair processes. Therefore, this review summarizes the foundation work for targeting Na(+) -dependent ion transporters in glia as a novel strategy to control important glial activities associated with Na(+) dynamics in different neurological disorders. GLIA 2016;64:1677-1697.

  5. Route, mechanism, and implications of proton import during Na+/K+ exchange by native Na+/K+-ATPase pumps.

    PubMed

    Vedovato, Natascia; Gadsby, David C

    2014-04-01

    A single Na(+)/K(+)-ATPase pumps three Na(+) outwards and two K(+) inwards by alternately exposing ion-binding sites to opposite sides of the membrane in a conformational sequence coupled to pump autophosphorylation from ATP and auto-dephosphorylation. The larger flow of Na(+) than K(+) generates outward current across the cell membrane. Less well understood is the ability of Na(+)/K(+) pumps to generate an inward current of protons. Originally noted in pumps deprived of external K(+) and Na(+) ions, as inward current at negative membrane potentials that becomes amplified when external pH is lowered, this proton current is generally viewed as an artifact of those unnatural conditions. We demonstrate here that this inward current also flows at physiological K(+) and Na(+) concentrations. We show that protons exploit ready reversibility of conformational changes associated with extracellular Na(+) release from phosphorylated Na(+)/K(+) pumps. Reversal of a subset of these transitions allows an extracellular proton to bind an acidic side chain and to be subsequently released to the cytoplasm. This back-step of phosphorylated Na(+)/K(+) pumps that enables proton import is not required for completion of the 3 Na(+)/2 K(+) transport cycle. However, the back-step occurs readily during Na(+)/K(+) transport when external K(+) ion binding and occlusion are delayed, and it occurs more frequently when lowered extracellular pH raises the probability of protonation of the externally accessible carboxylate side chain. The proton route passes through the Na(+)-selective binding site III and is distinct from the principal pathway traversed by the majority of transported Na(+) and K(+) ions that passes through binding site II. The inferred occurrence of Na(+)/K(+) exchange and H(+) import during the same conformational cycle of a single molecule identifies the Na(+)/K(+) pump as a hybrid transporter. Whether Na(+)/K(+) pump-mediated proton inflow may have any physiological or

  6. pNaKtide inhibits Na/K-ATPase reactive oxygen species amplification and attenuates adipogenesis

    PubMed Central

    Sodhi, Komal; Maxwell, Kyle; Yan, Yanling; Liu, Jiang; Chaudhry, Muhammad A.; Getty, Morghan; Xie, Zijian; Abraham, Nader G.; Shapiro, Joseph I.

    2015-01-01

    Obesity has become a worldwide epidemic and is a major risk factor for metabolic syndrome. Oxidative stress is known to play a role in the generation and maintenance of an obesity phenotype in both isolated adipocytes and intact animals. Because we had identified that the Na/K-ATPase can amplify oxidant signaling, we speculated that a peptide designed to inhibit this pathway, pNaKtide, might ameliorate an obesity phenotype. To test this hypothesis, we first performed studies in isolated murine preadipocytes (3T3L1 cells) and found that pNaKtide attenuated oxidant stress and lipid accumulation in a dose-dependent manner. Complementary experiments in C57Bl6 mice fed a high-fat diet corroborated our in vitro observations. Administration of pNaKtide in these mice reduced body weight gain, restored systemic redox and inflammatory milieu, and, crucially, improved insulin sensitivity. Thus, we propose that inhibition of Na/K-ATPase amplification of oxidative stress may ultimately be a novel way to combat obesity, insulin resistance, and metabolic syndrome. PMID:26601314

  7. Zero-gravity growth of NaF-NaCl eutectics in the NASA Skylab program

    NASA Technical Reports Server (NTRS)

    Yue, A. S.; Allen, F. G.; Yu, J. G.

    1976-01-01

    Continuous and discontinuous NaF fibers, embedded in a NaCl matrix, were produced in space and on earth. The production of continuous fibers in a eutectic mixture is attributed to the absence of convection current in the liquid during solidification in space. Image transmission and optical transmittance measurements of transverse sections of the space-grown and earth-grown ingots were made with a light microscope and a spectrometer. It is shown that better optical properties were obtained from samples grown in space. This was attributed to a better alignment of NaF fibers along the ingot axis. A new concept is advanced to explain the phenomenon of transmittance versus far infrared wavelength of the directionally solidified NaCl-NaF eutectic in terms of the two-dimensional Bragg Scattering and the polarization effect of Rayleigh scattering. This concept can be applied to other eutectic systems as long as the index of refraction of the matrix over a range of wavelengths is known. Experimental data are in agreement with the theoretical prediction.

  8. Plant Defensins NaD1 and NaD2 Induce Different Stress Response Pathways in Fungi

    PubMed Central

    Dracatos, Peter M.; Payne, Jennifer; Di Pietro, Antonio; Anderson, Marilyn A.; Plummer, Kim M.

    2016-01-01

    Nicotiana alata defensins 1 and 2 (NaD1 and NaD2) are plant defensins from the ornamental tobacco that have antifungal activity against a variety of fungal pathogens. Some plant defensins interact with fungal cell wall O-glycosylated proteins. Therefore, we investigated if this was the case for NaD1 and NaD2, by assessing the sensitivity of the three Aspergillus nidulans (An) O-mannosyltransferase (pmt) knockout (KO) mutants (An∆pmtA, An∆pmtB, and An∆pmtC). An∆pmtA was resistant to both defensins, while An∆pmtC was resistant to NaD2 only, suggesting NaD1 and NaD2 are unlikely to have a general interaction with O-linked side chains. Further evidence of this difference in the antifungal mechanism was provided by the dissimilarity of the NaD1 and NaD2 sensitivities of the Fusarium oxysporum f. sp. lycopersici (Fol) signalling knockout mutants from the cell wall integrity (CWI) and high osmolarity glycerol (HOG) mitogen-activated protein kinase (MAPK) pathways. HOG pathway mutants were sensitive to both NaD1 and NaD2, while CWI pathway mutants only displayed sensitivity to NaD2. PMID:27598152

  9. Effect of Na+ on surface fractal dimension of compacted bentonite

    NASA Astrophysics Data System (ADS)

    Xiang, G. S.; Xu, Y. F.; Jiang, H.

    2015-05-01

    Compacted Tsukinuno bentonite was immersed into NaCl solutions of different concentrations in oedometers, and the surface fractal dimension of bentonite-saline association was measured by nitrogen adsorption isotherms. The application of the Frenkel-Halsey-Hill equation and the Neimark thermodynamic method to nitrogen adsorption isotherms indicated that the surface roughness was greater for the bentonite-saline association. The surface fractal dimension of bentonite increased in the NaCl solution with low Na+ concentration, but decreased at high Na+ concentration. This process was accompanied by the same tendency in specific surface area and microporosity with the presence of Na+ coating in the clay particles.

  10. Na+-K+ pump regulation and skeletal muscle contractility.

    PubMed

    Clausen, Torben

    2003-10-01

    In skeletal muscle, excitation may cause loss of K+, increased extracellular K+ ([K+]o), intracellular Na+ ([Na+]i), and depolarization. Since these events interfere with excitability, the processes of excitation can be self-limiting. During work, therefore, the impending loss of excitability has to be counterbalanced by prompt restoration of Na+-K+ gradients. Since this is the major function of the Na+-K+ pumps, it is crucial that their activity and capacity are adequate. This is achieved in two ways: 1) by acute activation of the Na+-K+ pumps and 2) by long-term regulation of Na+-K+ pump content or capacity. 1) Depending on frequency of stimulation, excitation may activate up to all of the Na+-K+ pumps available within 10 s, causing up to 22-fold increase in Na+ efflux. Activation of the Na+-K+ pumps by hormones is slower and less pronounced. When muscles are inhibited by high [K+]o or low [Na+]o, acute hormone- or excitation-induced activation of the Na+-K+ pumps can restore excitability and contractile force in 10-20 min. Conversely, inhibition of the Na+-K+ pumps by ouabain leads to progressive loss of contractility and endurance. 2) Na+-K+ pump content is upregulated by training, thyroid hormones, insulin, glucocorticoids, and K+ overload. Downregulation is seen during immobilization, K+ deficiency, hypoxia, heart failure, hypothyroidism, starvation, diabetes, alcoholism, myotonic dystrophy, and McArdle disease. Reduced Na+-K+ pump content leads to loss of contractility and endurance, possibly contributing to the fatigue associated with several of these conditions. Increasing excitation-induced Na+ influx by augmenting the open-time or the content of Na+ channels reduces contractile endurance. Excitability and contractility depend on the ratio between passive Na+-K+ leaks and Na+-K+ pump activity, the passive leaks often playing a dominant role. The Na+-K+ pump is a central target for regulation of Na+-K+ distribution and excitability, essential for second

  11. Na+ channel function, regulation, structure, trafficking and sequestration

    PubMed Central

    Chen-Izu, Ye; Shaw, Robin M; Pitt, Geoffrey S; Yarov-Yarovoy, Vladimir; Sack, Jon T; Abriel, Hugues; Aldrich, Richard W; Belardinelli, Luiz; Cannell, Mark B; Catterall, William A; Chazin, Walter J; Chiamvimonvat, Nipavan; Deschenes, Isabelle; Grandi, Eleonora; Hund, Thomas J; Izu, Leighton T; Maier, Lars S; Maltsev, Victor A; Marionneau, Celine; Mohler, Peter J; Rajamani, Sridharan; Rasmusson, Randall L; Sobie, Eric A; Clancy, Colleen E; Bers, Donald M

    2015-01-01

    This paper is the second of a series of three reviews published in this issue resulting from the University of California Davis Cardiovascular Symposium 2014: Systems approach to understanding cardiac excitation–contraction coupling and arrhythmias: Na+ channel and Na+ transport. The goal of the symposium was to bring together experts in the field to discuss points of consensus and controversy on the topic of sodium in the heart. The present review focuses on Na+ channel function and regulation, Na+ channel structure and function, and Na+ channel trafficking, sequestration and complexing. PMID:25772290

  12. Jahn–Teller Assisted Na Diffusion for High Performance Na Ion Batteries

    SciTech Connect

    Li, Xin; Wang, Yan; Wu, Di; Liu, Lei; Bo, Shou-Hang; Ceder, Gerbrand

    2016-08-30

    Na energy storage technology is strategically attractive for large scale applications such as grid energy storage. Here, we show in this paper that there is a clear relation between the Jahn$-$Teller activity of a transition metal ion at the end of charge and the mobility of Na in a cathode material. This is particularly important as mobility at the end of charge limits the capacity of current materials. Consequently, by using this classical piece of physics in the battery world, it is possible to create higher capacity Na-cathode materials. Even more exciting is that the ideal element to impart this effect on cathodes is Fe, which is the least expensive of the transition metal oxides and can therefore enable low cost cathode materials.

  13. Synthesis of Na-A and/or Na-X zeolite/porous carbon composites from carbonized rice husk

    SciTech Connect

    Katsuki, Hiroaki; Komarneni, Sridhar

    2009-07-15

    Na-A and/or Na-X zeolite/porous carbon composites were prepared under hydrothermal conditions by NaOH dissolution of silica first from carbonized rice husk followed by addition of NaAlO{sub 2} and in situ crystallization of zeolites i.e., using a two-step process. When a one-step process was used, both Na-A and Na-X zeolites crystallized on the surface of carbon. Na-A or Na-X zeolite crystals were prepared on the porous carbonized rice husk at 90 deg. C for 2-6 h by changing the SiO{sub 2}/Al{sub 2}O{sub 3}, H{sub 2}O/Na{sub 2}O and Na{sub 2}O/SiO{sub 2} molar ratios of precursors in the two-step process. The surface area and NH{sub 4}{sup +}-cation exchange capacity (CEC) of Na-A zeolite/porous carbon were found to be 171 m{sup 2}/g and 506 meq/100 g, respectively, while those of Na-X zeolite/porous carbon composites were 676 m{sup 2}/g and 317 meq/100 g, respectively. Na-A and Na-X zeolites are well-known microporous and hydrophilic materials while carbonized rice husk was found to be mesoporous (pores of {approx}3.9 nm) and hydrophobic. These hybrid microporous-mesoporous and hydrophilic-hydrophobic composites are expected to be useful for decontamination of metal cations as well as organic contaminants simultaneously. - Graphical Abstract: Novel Na-X zeolite/porous carbon composite.

  14. Specific oxidation pattern of soluble starch with TEMPO-NaBr-NaClO system.

    PubMed

    Hao, Jie; Lu, Jiaojiao; Xu, Naiyu; Linhardt, Robert J; Zhang, Zhenqing

    2016-08-01

    Oxidized starch, one of the most important starch derivatives, has many different properties and applications. Currently, there are two ways to produce oxidized starch, through specific and nonspecific oxidation. Specific oxidation using the stable nitroxyl radical, 2,2,6,6-tetramethyl preparidinloxy (TEMPO), with NaBr and NaClO can produce oxidized starches with different properties under good quality control. In the current study, we examine the products of specifically oxidized starch. As the amount of oxidant and the temperature, two critical factors impacting the oxidation of starch were thoroughly investigated. Analysis of the molecular weight (MW), degree of oxidization (DO) and the detailed structures of corresponding products was accomplished using gel permeation chromatography with multi-angle laser light scattering (GPC-MALLS), infrared (IR) spectroscopy, nuclear magnetic resonance (NMR) spectroscopy, and quadrapole time-of-flight mass spectrometry (Q/TOF-MS). According to the analytical results, the oxidation patterns of starch treated with specific oxidant TEMPO-NaBr-NaClO were established. When high amounts of oxidant was applied, more glucose residues within starch were oxidized to glucuronic acids (higher DO) and substantial degradation to starch oligosaccharides was observed. By selecting a reaction temperature of 25°C a high DO could be obtained for a given amount of oxidant. The reducing end sugar residue within oxidized starch was itself oxidized and ring opened in all TEMPO-NaBr-NaClO reactions. Furthermore, extra oxidant generated additional novel structures in the reducing end residues of some products, particularly in low temperature reactions.

  15. Neutron spectroscopy of water dynamics in NaX and NaA zeolites

    NASA Astrophysics Data System (ADS)

    Kamitakahara, William A.; Wada, Noboru

    2008-04-01

    We have investigated the dynamics of water molecules in zeolites NaA and NaX by high-resolution quasielastic neutron scattering methods. Between 260 and 310 K, the local translational diffusive motion of water in the zeolites is one to two orders of magnitude slower than in bulk water. The Q dependence of the scattering shows effects of confinement and the presence of both relatively mobile and immobile molecules. The speed of the diffusive motion depends strongly on hydration level. Comparison with other hydrated siliceous materials indicates that the host charge per water molecule is a major factor in determining the time scale of diffusion.

  16. Design and implementation of the NaI(Tl)/CsI(Na) detectors output signal generator

    NASA Astrophysics Data System (ADS)

    Zhou, Xu; Liu, Cong-Zhan; Zhao, Jian-Ling; Zhang, Fei; Zhang, Yi-Fei; Li, Zheng-Wei; Zhang, Shuo; Li, Xu-Fang; Lu, Xue-Feng; Xu, Zhen-Ling; Lu, Fang-Jun

    2014-02-01

    We designed and implemented a signal generator that can simulate the output of the NaI(Tl)/CsI(Na) detectors' pre-amplifier onboard the Hard X-ray Modulation Telescope (HXMT). Using the development of the FPGA (Field Programmable Gate Array) with VHDL language and adding a random constituent, we have finally produced the double exponential random pulse signal generator. The statistical distribution of the signal amplitude is programmable. The occurrence time intervals of the adjacent signals contain negative exponential distribution statistically.

  17. FT-IR and XRD analysis of natural Na-bentonite and Cu(II)-loaded Na-bentonite.

    PubMed

    Zhirong, Liu; Azhar Uddin, Md; Zhanxue, Sun

    2011-09-01

    Na-bentonite has been studied extensively because of its strong adsorption capacity and complexation ability. In this work, surface area, total pore volume, mean pore diameter, TG, DTA, FT-IR and XRD were carried out in order to reveal the characteristics of natural Na-bentonite. XRD and FT-IR of natural Na-bentonite (China) and Cu-loaded Na-bentonite as a function of Na-bentonite dosage and temperature using batch technique were characterized in detail, respectively.

  18. FT-IR and XRD analysis of natural Na-bentonite and Cu(II)-loaded Na-bentonite

    NASA Astrophysics Data System (ADS)

    Zhirong, Liu; Azhar Uddin, Md.; Zhanxue, Sun

    2011-09-01

    Na-bentonite has been studied extensively because of its strong adsorption capacity and complexation ability. In this work, surface area, total pore volume, mean pore diameter, TG, DTA, FT-IR and XRD were carried out in order to reveal the characteristics of natural Na-bentonite. XRD and FT-IR of natural Na-bentonite (China) and Cu-loaded Na-bentonite as a function of Na-bentonite dosage and temperature using batch technique were characterized in detail, respectively.

  19. The NA62 experiment at CERN

    NASA Astrophysics Data System (ADS)

    Piccini, Mauro

    2016-11-01

    The rare decays K → πvv¯ are excellent processes to make tests of new physics at the highest scale complementary to LHC thanks to their theoretically cleanness. The NA62 experiment at CERN SPS aims to collect of the order of 100 events in two years of data taking for the decay K+ → π+vv¯, keeping the background at the level of 10%. Part of the experimental apparatus has been commissioned during a technical run in 2012. The diverse and innovative experimental techniques will be explained and some preliminary results obtained during the 2014 pilot run will be reviewed.

  20. Status of the NA62 Experiment

    NASA Astrophysics Data System (ADS)

    Palladino, Vito

    2016-04-01

    The rare decays {{{K}}^ + } to {π ^ + }{{ν bar ν }} are excellent processes to make tests of new physics at the highest scale complementary to LHC thanks to their theoretically cleaness. The NA62 experiment at CERN SPS aims to collect of the order of 100 events in two years of data taking, keeping the background at the level of 10%. Part of the experimental apparatus has been commissioned during a technical run in 2012. The physics prospects and the status of the experiment will be reviewed after the commissioning run of 2014 and the data taking in 2015.

  1. The NA62 Gigatracker pixel detector system

    NASA Astrophysics Data System (ADS)

    Mazza, G.; Ceccucci, A.; Cortina, E.; Cotta Ramusino, A.; Dellacasa, G.; Fiorini, M.; Garbolino, S.; Jarron, P.; Kaplon, J.; Kluge, A.; Marchetto, F.; Martin, E.; Martoiu, S.; Noy, M.; Petrucci, F.; Riedler, P.; Rivetti, A.; Tiuraniemi, S.

    2010-05-01

    The silicon tracker for the NA62 experiment has to provide both a time resolution of 150 ps rms and a space resolution of about 100 μm rms. These challenging specifications require the development of a new readout electronics in order to address the problem of measuring the tracks arrival time with such a high channel density. Moreover, the high particle density (up to 1.5 MHz/mm2 in the center and 0.8-1 GHz in total) requires a high speed measurement and data transmission in order to keep the dead time below 1%.

  2. Novel regulation of cell [Na(+)] in macula densa cells: apical Na(+) recycling by H-K-ATPase.

    PubMed

    Peti-Peterdi, János; Bebok, Zsuzsa; Lapointe, Jean-Yves; Bell, P Darwin

    2002-02-01

    Na-K-ATPase is the nearly ubiquitous enzyme that maintains low-Na(+), high-K(+) concentrations in cells by actively extruding Na(+) in exchange for K(+). The prevailing paradigm in polarized absorbing epithelial cells, including renal nephron segments and intestine, has been that Na-K-ATPase is restricted to the basolateral membrane domain, where it plays a prominent role in Na(+) absorption. We have found, however, that macula densa (MD) cells lack functionally and immunologically detectable amounts of Na-K-ATPase protein. In fact, these cells appear to regulate their cytosolic [Na(+)] via another member of the P-type ATPase family, the colonic form of H-K-ATPase, which is located at the apical membrane in these cells. We now report that this constitutively expressed apical MD colonic H-K-ATPase can function as a Na(H)-K-ATPase and regulate cytosolic [Na(+)] in a novel manner. This apical Na(+)-recycling mechanism may be important as part of the sensor function of MD cells and represents a new paradigm in cell [Na(+)] regulation.

  3. Penning and associative ionization in crossed-beam Na/Na collisions assisted by strong resonant laser fields

    SciTech Connect

    Weiner, J.; Polak-Dingels, P.

    1981-01-01

    We observe the production of Na/sub 2//sup +/ and Na/sup +/ arising from single collisions between crossed beams of sodium atoms when a laser field is tuned near the Na(3p /sup 2/P/sub 3/2/) and Na(3p /sup 2/P/sub 1/2/) transitions. Measurements of ion intensity vs laser intensity show that at moderately high power true laser-induced processes dominate over purely collisional effects. Relative intensity of mass-selected ions produced at either member of the Na resonance doublet shows conclusively that Na/sup +/ does not arise simply from photodissociation of Na/sub 2//sup +/ but must result from a direct, laser-induced collisional ionization.

  4. Vanadate sensitivity of Na+, K+-ATPase from Schistosoma mansoni and its modulation by Na+, K+ and Mg2+.

    PubMed

    Noel, F; Pardon, R S

    1989-01-01

    Vanadate inhibitory effects on Na+, K+-ATPases from carcass of Schistosoma mansoni and from lamb kidney outer medulla were compared in the presence of various concentrations of Na+, K+ and Mg2+. Depending on the ionic conditions, the schistosomal Na+, K+-ATPase was 2.4- to 175-fold less sensitive to vanadate than the lamb kidney enzyme. In 100 mM Na+, 3 mM K+ and 3 mM Mg2+, schistosomal Na+, K+-ATPase was surprisingly resistant to vanadate (I50 = 944 microM). The difference in vanadate sensitivity between schistosomal and lamb Na+, K+-ATPases may be due to a species difference in the efficacy of Na+, K+ and Mg2+ in promoting conformational changes between E1 and E2 forms of the enzyme.

  5. NaSrMn2F7, NaCaFe2F7, and NaSrFe2F7: novel single crystal pyrochlore antiferromagnets

    NASA Astrophysics Data System (ADS)

    Sanders, M. B.; Krizan, J. W.; Plumb, K. W.; McQueen, T. M.; Cava, R. J.

    2017-02-01

    The crystal structures and magnetic properties of three previously unreported A2B2F7 pyrochlore materials, NaSrMn2F7, NaCaFe2F7, and NaSrFe2F7 are presented. In these compounds, either S  =  2Fe2+ or S  =  5/2Mn2+ is on the B site, while nonmagnetic Na and Ca (Na and Sr) are disordered on the A site. The materials, which were grown as crystals via the floating zone method, display high effective magnetic moments and large Curie-Weiss thetas. Despite these characteristics, no ordering transition is detected. However, freezing of the magnetic spins, characterized by peaks in the susceptibility or specific heat, is observed at very low temperatures. The empirical frustration index, f  =  -θ CW/T f, for the materials are 36 (NaSrMn2F7), 27 (NaSrFe2F7), and 19 (NaCaFe2F7). AC susceptibility, DC susceptibility, and heat capacity measurements are used to characterize the observed spin glass behavior. The results suggest that the compounds are frustrated pyrochlore antiferromagnets with weak bond disorder. The magnetic phenomena that these fluoride pyrochlores exhibit, in addition to their availability as relatively large single crystals, make them promising candidates for the study of geometric magnetic frustration.

  6. The NA62 GigaTracker

    NASA Astrophysics Data System (ADS)

    Aglieri Rinella, G.; Feito, D. Alvarez; Arcidiacono, R.; Biino, C.; Bonacini, S.; Ceccucci, A.; Chiozzi, S.; Gil, E. Cortina; Ramusino, A. Cotta; Degrange, J.; Fiorini, M.; Gamberini, E.; Gianoli, A.; Kaplon, J.; Kluge, A.; Mapelli, A.; Marchetto, F.; Minucci, E.; Morel, M.; Noël, J.; Noy, M.; Perktold, L.; Perrin-Terrin, M.; Petagna, P.; Petrucci, F.; Poltorak, K.; Romagnoli, G.; Ruggiero, G.; Velghe, B.; Wahl, H.

    2017-02-01

    The GigaTracker is a hybrid silicon pixel detector built for the NA62 experiment aiming at measuring the branching fraction of the ultra-rare kaon decay K+ →π+ ν ν bar at the CERN SPS. The detector has to track particles in a beam with a flux reaching 1.3 MHz/mm2 and provide single-hit timing with 200 ps RMS resolution for a total material budget of less than 0.5% X0 per station. The tracker comprises three 60.8 mm×27 mm stations installed in vacuum (∼10-6 mbar) and cooled with liquid C6F14 circulating through micro-channels etched inside a few hundred micron thick silicon plates. Each station is composed of a 200 μm thick silicon sensor read out by 2×5 custom 100 μm thick ASICs, called TDCPix. Each chip contains 40×45 asynchronous pixels, 300 μm×300 μm each and is instrumented with 100 ps bin time-to-digital converters. In order to cope with the high rate, the TDCPix is equipped with four 3.2 Gb/s serialisers sending out the data. We will describe the detector and the results from the 2014 and 2015 NA62 runs.

  7. Elevated intracellular Na(+) concentrations in developing spinal neurons.

    PubMed

    Lindsly, Casie; Gonzalez-Islas, Carlos; Wenner, Peter

    2017-03-01

    Over 25 years ago it was first reported that intracellular chloride levels (Cl(-)in ) were higher in developing neurons than in maturity. This finding has had significant implications for understanding the excitability of developing networks and recognizing the underlying causes of hyperexcitability associated with disease and neural injury. While there is some evidence that intracellular sodium levels (Na(+)in ) change during the development of non-neural cells, it has largely been assumed that Na(+)in is the same in developing and mature neurons. Here, using the sodium indicator SBFI, we test this idea and find that Na(+)in is significantly higher in embryonic spinal motoneurons and interneurons than in maturity. We find that Na(+)in reaches ~ 60 mM in mid-embryonic development and is then reduced to ~ 30 mM in late embryonic development. By retrogradely labeling motoneurons with SBFI we can reliably follow Na(+)in levels in vitro for hours. Bursts of spiking activity, and blocking voltage-gated sodium channels did not influence observed motoneuron sodium levels. On the other hand, Na(+)in was reduced by blocking the Na(+) -K(+) -2Cl(-) cotransporter NKCC1, and was highly sensitive to changes in external Na(+) and a blocker of the Na(+) /K(+) ATPase. Our findings suggest that the Na(+) gradient is weaker in embryonic neuronal development and strengthens in maturity in a manner similar to that of Cl(-) .

  8. Minimizing Load Effects on NA4 Gear Vibration Diagnostic Parameter

    NASA Technical Reports Server (NTRS)

    Dempsey, Paula J.; Zakrajsek, James J.

    2001-01-01

    NA4 is a vibration diagnostic parameter, developed by researchers at NASA Glenn Research Center, for health monitoring of gears in helicopter transmissions. The NA4 reacts to the onset of gear pitting damage and continues to react to the damage as it spreads. This research also indicates NA4 reacts similarly to load variations. The sensitivity of NA4 to load changes will substantially affect its performance on a helicopter gearbox that experiences continuously changing load throughout its flight regimes. The parameter NA4 has been used to monitor gear fatigue tests at constant load. At constant load, NA4 effectively detects the onset of pitting damage and tracks damage severity. Previous research also shows that NA4 reacts to changes in load applied to the gears in the same way it reacts to the onset of pitting damage. The method used to calculate NA4 was modified to minimize these load effects. The modified NA4 parameter was applied to four sets of experimental data. Results indicate the modified NA4 is no longer sensitive to load changes, but remains sensitive to pitting damage.

  9. Rydberg States of Na-doped Helium Nanodroplets

    NASA Astrophysics Data System (ADS)

    Drabbels, Marcel

    2008-03-01

    The dynamics of excited states of Na atoms deposited on the surface of helium nanodroplets has been investigated with velocity map ion imaging, photoelectron spectroscopy and time-of-flight mass-spectroscopy. For the first time, the excitation spectra of Na-doped helium nanodroplets corresponding to Rydberg states of Na atoms have been measured from the lowest excited 3p state up to the ionization threshold. All lines in the excitation spectra are shifted and broadened with respect to the corresponding atomic lines. In addition to bare Na* atoms also Na*HeN (N = 1-6) exciplexes are detected upon excitation. Photoelectron spectroscopy reveals the desorption of Na* not only in the initially excited states but also in lower lying states, indicating that relaxation plays an important role. The recorded velocity distributions show interesting characteristics: for the lowest states the mean kinetic energy of Na* increases linearly with excitation energy. The velocity distributions of Na*HeN exciplexes do not manifest such remarkable properties. The observations can be largely explained by assuming that the interaction of Na* with the helium nanodroplet can be described by the sum of Na*-He pair potentials.

  10. The natural course of disease following HIV-1 infection in dar es salaam, Tanzania: a study among hotel workers relating clinical events to CD4 T-lymphocyte counts.

    PubMed

    Bakari, Muhammad; Urassa, Willy; Pallangyo, Kisali; Swai, Andrew; Mhalu, Fred; Biberfeld, Gunnel; Sandström, Eric

    2004-01-01

    Current HIV management guidelines are based on natural history studies from the developed world. Data on the similarity of the natural course of HIV-1 infection conflict with studies in the developing world. A cohort of 1887 hotel workers with no access to antiretroviral therapy was followed between 1990 and 1998 in Dar es Salaam through annual clinical evaluations and CD4+ T-lymphocyte (CD4 cell) count determinations. 196 (10.4%) were HIV-1 sero-prevalents; 133 (7.9%) were HIV-1 sero-incidents; and 1558 (82.6%) remained HIV seronegative. Follow-up duration was 13,719 and 82,742 months for HIV-1 seropositives and HIV seronegatives respectively. Clinical events occurred at median CD4 cell counts similar to those previously reported from the developed world, but death occurred at higher counts. Off-duty last 6 months, chronic diarrhoea and a faster CD4 cell count decline were associated with faster disease progression and death. In Tanzania HIV natural history is similar to that from the developed world and similar management guidelines could be employed.

  11. Direct interaction of Na-azide with the KATP channel.

    PubMed

    Trapp, S; Ashcroft, F M

    2000-11-01

    1. The effects of the metabolic inhibitor sodium azide were tested on excised macropatches from Xenopus oocytes expressing cloned ATP-sensitive potassium (KATP) channels of the Kir6.2/SUR1 type. 2. In inside-out patches from oocytes expressing Kir6.2 delta C36 (a truncated form of Kir6.2 that expresses in the absence of SUR), intracellular Na-azide inhibited macroscopic currents with an IC50 of 11 mM. The inhibitory effect of Na-azide was mimicked by the same concentration of NaCl, but not by sucrose. 3. Na-azide and NaCl blocked Kir6.2/SUR1 currents with IC50 of 36 mM and 19 mM, respectively. Inhibition was abolished in the absence of intracellular Mg2+. In contrast, Kir6.2 delta C36 currents were inhibited by Na-azide both in the presence or absence of intracellular Mg2+. 4. Kir6.2/SUR1 currents were less sensitive to 3 mM Na-azide in the presence of MgATP. This apparent reduction in sensitivity is caused by a small activatory effect of Na-azide conferred by SUR. 5. We conclude that, in addition to its well-established inhibitory effect on cellular metabolism, which leads to activation of KATP channels in intact cells, intracellular Na-azide has direct effects on the KATP channel. Inhibition is intrinsic to Kir6.2, is mediated by Na+, and is modulated by SUR. There is also a small, ATP-dependent, stimulatory effect of Na-azide mediated by the SUR subunit. The direct effects of 3 mM Na-azide on KATP channels are negligible in comparison to the metabolic activation produced by the same Na-azide concentration.

  12. Theoretical calculation of low-lying states of NaAr and NaXe

    NASA Technical Reports Server (NTRS)

    Laskowski, B. C.; Langhoff, S. R.; Stallcop, J. R.

    1981-01-01

    Potential curves as well as dipole moments and linking transition moments are calculated for the ground X 2 Sigma + and low lying excited A 2 Pi, B 2 Sigma +, C 2 Sigma +, (4) 2 Sigma +, (2) 2 Pi and (1) 2 Delta states of NaAr and NaXe. Calculations are performed using a self-consistent field plus configuration-interaction procedure with the core electrons replaced by an ab initio effective core potential. The potential curves obtained are found to be considerably less repulsive than the semiempirical curves of Pascale and Vandeplanque (1974) and to agree well with existing experimental data, although the binding energies of those states having potential minima due to van der Waals interactions are underestimated. Emission bands are also calculated for the X 2 Sigma + - C 2 Sigma + excimer transitions of NaAr and NaXe using the calculated transition moments and potential curves, and shown to agree well with experiment on the short-wavelength side of the maximum.

  13. 24Mg(p, α)21Na reaction study for spectroscopy of 21Na

    DOE PAGES

    Cha, S. M.; Chae, K. Y.; Kim, A.; ...

    2015-11-03

    The Mg-24(p, alpha)Na-21 reaction was measured at the Holifield Radioactive Ion Beam Facility at Oak Ridge National Laboratory in order to better constrain the spins and parities of the energy levels in Na-21 for the astrophysically important F-17(alpha, p)Ne-20 reaction rate calculation. 31-MeV proton beams from the 25-MV tandem accelerator and enriched Mg-24 solid targets were used. When recoiling He-4 particles from the Mg-24(p, alpha)Na-21 reaction we used a highly segmented silicon detector array to detect them; it measured the yields of He-4 particles over a range of angles simultaneously. A observed a new level at 6661 ± 5 keVmore » in the present work. The extracted angular distributions for the first four levels of Na-21 and the results from distorted wave Born approximation (DWBA) calculations were compared to verify and extract the angular momentum transfer.« less

  14. Regulation of persistent Na current by interactions between beta subunits of voltage-gated Na channels.

    PubMed

    Aman, Teresa K; Grieco-Calub, Tina M; Chen, Chunling; Rusconi, Raffaella; Slat, Emily A; Isom, Lori L; Raman, Indira M

    2009-02-18

    The beta subunits of voltage-gated Na channels (Scnxb) regulate the gating of pore-forming alpha subunits, as well as their trafficking and localization. In heterologous expression systems, beta1, beta2, and beta3 subunits influence inactivation and persistent current in different ways. To test how the beta4 protein regulates Na channel gating, we transfected beta4 into HEK (human embryonic kidney) cells stably expressing Na(V)1.1. Unlike a free peptide with a sequence from the beta4 cytoplasmic domain, the full-length beta4 protein did not block open channels. Instead, beta4 expression favored open states by shifting activation curves negative, decreasing the slope of the inactivation curve, and increasing the percentage of noninactivating current. Consequently, persistent current tripled in amplitude. Expression of beta1 or chimeric subunits including the beta1 extracellular domain, however, favored inactivation. Coexpressing Na(V)1.1 and beta4 with beta1 produced tiny persistent currents, indicating that beta1 overcomes the effects of beta4 in heterotrimeric channels. In contrast, beta1(C121W), which contains an extracellular epilepsy-associated mutation, did not counteract the destabilization of inactivation by beta4 and also required unusually large depolarizations for channel opening. In cultured hippocampal neurons transfected with beta4, persistent current was slightly but significantly increased. Moreover, in beta4-expressing neurons from Scn1b and Scn1b/Scn2b null mice, entry into inactivated states was slowed. These data suggest that beta1 and beta4 have antagonistic roles, the former favoring inactivation, and the latter favoring activation. Because increased Na channel availability may facilitate action potential firing, these results suggest a mechanism for seizure susceptibility of both mice and humans with disrupted beta1 subunits.

  15. [Na] and [K] dependence of the Na/K pump current-voltage relationship in guinea pig ventricular myocytes

    PubMed Central

    1989-01-01

    Na/K pump current was determined between -140 and +60 mV as steady- state, strophanthidin-sensitive, whole-cell current in guinea pig ventricular myocytes, voltage-clamped and internally dialyzed via wide- tipped pipettes. Solutions were designed to minimize all other components of membrane current. A device for exchanging the solution inside the pipette permitted investigation of Na/K pump current-voltage (I-V) relationships at several levels of pipette [Na] [( Na]pip) in a single cell; the effects of changes in external [Na] [( Na]o) or external [K] [( K]o) were also studied. At 50 mM [Na]pip, 5.4 mM [K]o, and approximately 150 mM [Na]o, Na/K pump current was steeply voltage dependent at negative potentials but was approximately constant at positive potentials. Under those conditions, reduction of [Na]o enhanced pump current at negative potentials but had little effect at positive potentials: at zero [Na]o, pump current was only weakly voltage dependent. At 5.4 mM [K]o and approximately 150 mM [Na]o, reduction of [Na]pip from 50 mM scaled down the sigmoid pump I-V relationship and shifted it slightly to the right (toward more positive potentials). Pump current at 0 mV was activated by [Na]pip according to the Hill equation with best-fit K0.5 approximately equal to 11 mM and Hill coefficient nH approximately equal to 1.4. At zero [Na]o, reduction of [Na]pip seemed to simply scale down the relatively flat pump I-V relationship: Hill fit parameters for pump activation by [Na]pip at 0 mV were K0.5 approximately equal to 10 mM, nH approximately equal to 1.4. At 50 mM [Na]pip and high [Na]o, reduction of [K]o from 5.4 mM scaled down the sigmoid I-V relationship and shifted it slightly to the right: at 0 mV, K0.5 approximately equal to 1.5 mM and nH approximately equal to 1.0. At zero [Na]o, lowering [K]o simply scaled down the flat pump I-V relationships yielding, at 0 mV, K0.5 approximately equal to 0.2 mM, nH approximately equal to 1.1. The voltage

  16. Coordinated regulation of cardiac Na(+)/Ca (2+) exchanger and Na (+)-K (+)-ATPase by phospholemman (FXYD1).

    PubMed

    Cheung, Joseph Y; Zhang, Xue-Qian; Song, Jianliang; Gao, Erhe; Chan, Tung O; Rabinowitz, Joseph E; Koch, Walter J; Feldman, Arthur M; Wang, JuFang

    2013-01-01

    Phospholemman (PLM) is the founding member of the FXYD family of regulators of ion transport. PLM is a 72-amino acid protein consisting of the signature PFXYD motif in the extracellular N terminus, a single transmembrane (TM) domain, and a C-terminal cytoplasmic tail containing three phosphorylation sites. In the heart, PLM co-localizes and co-immunoprecipitates with Na(+)-K(+)-ATPase, Na(+)/Ca(2+) exchanger, and L-type Ca(2+) channel. The TM domain of PLM interacts with TM9 of the α-subunit of Na(+)-K(+)-ATPase, while its cytoplasmic tail interacts with two small regions (spanning residues 248-252 and 300-304) of the proximal intracellular loop of Na(+)/Ca(2+) exchanger. Under stress, catecholamine stimulation phosphorylates PLM at serine(68), resulting in relief of inhibition of Na(+)-K(+)-ATPase by decreasing K(m) for Na(+) and increasing V(max), and simultaneous inhibition of Na(+)/Ca(2+) exchanger. Enhanced Na(+)-K(+)-ATPase activity lowers intracellular Na(+), thereby minimizing Ca(2+) overload and risks of arrhythmias. Inhibition of Na(+)/Ca(2+) exchanger reduces Ca(2+) efflux, thereby preserving contractility. Thus, the coordinated actions of PLM during stress serve to minimize arrhythmogenesis and maintain inotropy. In acute cardiac ischemia and chronic heart failure, either expression or phosphorylation of PLM or both are altered. PLM regulates important ion transporters in the heart and offers a tempting target for development of drugs to treat heart failure.

  17. Pyrophosphate-Fueled Na+ and H+ Transport in Prokaryotes

    PubMed Central

    Malinen, Anssi M.; Luoto, Heidi H.

    2013-01-01

    SUMMARY In its early history, life appeared to depend on pyrophosphate rather than ATP as the source of energy. Ancient membrane pyrophosphatases that couple pyrophosphate hydrolysis to active H+ transport across biological membranes (H+-pyrophosphatases) have long been known in prokaryotes, plants, and protists. Recent studies have identified two evolutionarily related and widespread prokaryotic relics that can pump Na+ (Na+-pyrophosphatase) or both Na+ and H+ (Na+,H+-pyrophosphatase). Both these transporters require Na+ for pyrophosphate hydrolysis and are further activated by K+. The determination of the three-dimensional structures of H+- and Na+-pyrophosphatases has been another recent breakthrough in the studies of these cation pumps. Structural and functional studies have highlighted the major determinants of the cation specificities of membrane pyrophosphatases and their potential use in constructing transgenic stress-resistant organisms. PMID:23699258

  18. The paranodal cytoskeleton clusters Na(+) channels at nodes of Ranvier.

    PubMed

    Amor, Veronique; Zhang, Chuansheng; Vainshtein, Anna; Zhang, Ao; Zollinger, Daniel R; Eshed-Eisenbach, Yael; Brophy, Peter J; Rasband, Matthew N; Peles, Elior

    2017-01-30

    A high density of Na(+) channels at nodes of Ranvier is necessary for rapid and efficient action potential propagation in myelinated axons. Na+ channel clustering is thought to depend on two axonal cell adhesion molecules that mediate interactions between the axon and myelinating glia at the nodal gap (i.e., NF186) and the paranodal junction (i.e., Caspr). Here we show that while Na(+) channels cluster at nodes in the absence of NF186, they fail to do so in double conditional knockout mice lacking both NF186 and the paranodal cell adhesion molecule Caspr, demonstrating that a paranodal junction-dependent mechanism can cluster Na(+) channels at nodes. Furthermore, we show that paranode-dependent clustering of nodal Na(+) channels requires axonal βII spectrin which is concentrated at paranodes. Our results reveal that the paranodal junction-dependent mechanism of Na(+)channel clustering is mediated by the spectrin-based paranodal axonal cytoskeleton.

  19. Neutron diffraction studies of the Na-ion battery electrode materials NaCoCr2(PO4)3, NaNiCr2(PO4)3, and Na2Ni2Cr(PO4)3

    NASA Astrophysics Data System (ADS)

    Yahia, H. Ben; Essehli, R.; Avdeev, M.; Park, J.-B.; Sun, Y.-K.; Al-Maadeed, M. A.; Belharouak, I.

    2016-06-01

    The new compounds NaCoCr2(PO4)3, NaNiCr2(PO4)3, and Na2Ni2Cr(PO4)3 were synthesized by sol-gel method and their crystal structures were determined by using neutron powder diffraction data. These compounds were characterized by galvanometric cycling and cyclic voltammetry. NaCoCr2(PO4)3, NaNiCr2(PO4)3, and Na2Ni2Cr(PO4)3 crystallize with a stuffed α-CrPO4-type structure. The structure consists of a 3D-framework made of octahedra and tetrahedra that are sharing corners and/or edges generating channels along [100] and [010], in which the sodium atoms are located. Of significance, in the structures of NaNiCr2(PO4)3, and Na2Ni2Cr(PO4)3 a statistical disorder Ni2+/Cr3+ was observed on both the 8g and 4a atomic positions, whereas in NaCoCr2(PO4)3 the statistical disorder Co2+/Cr3+ was only observed on the 8g atomic position. When tested as negative electrode materials, NaCoCr2(PO4)3, NaNiCr2(PO4)3, and Na2Ni2Cr(PO4)3 delivered specific capacities of 352, 385, and 368 mA h g-1, respectively, which attests to the electrochemical activity of sodium in these compounds.

  20. Simulation of Na D emission near Europa during eclipse

    USGS Publications Warehouse

    Cassidy, T.A.; Johnson, R.E.; Geissler, P.E.; Leblanc, F.

    2008-01-01

    The Cassini imaging science subsystem observed Europa in eclipse during Cassini's Jupiter flyby. The disk-resolved observations revealed a spatially nonuniform emission in the wavelength range of 200-1050 nm (clear filters). By building on observations and simulations of Europa's Na atmosphere and torus we find that electron-excited Na in Europa's tenuous atmosphere can account for the observed emission if the Na is ejected preferentially from Europa's dark terrain. Copyright 2008 by the American Geophysical Union.

  1. Magnesium correction to the NaKCa chemical geothermometer

    USGS Publications Warehouse

    Fournier, R.O.; Potter, R.W.

    1979-01-01

    Equations and graphs have been devised to correct for the adverse effects of magnesium upon the Na-K-Ca chemical geothermometer. Either the equations or graphs can be used to determine appropriate temperature corrections for given waters with calculated NaKCa temperatures > 70??C and R 50 are probably derived from relatively cool aquifers with temperatures approximately equal to the measured spring temperature, irrespective of much higher calculated Na-K-Ca temperatures. ?? 1979.

  2. Kinetic properties and Na+ dependence of rheogenic Na(+)-HCO3- co-transport in frog retinal pigment epithelium.

    PubMed Central

    la Cour, M

    1991-01-01

    1. Na(+)-HCO3- co-transport across the retinal membrane of the frog retinal pigment epithelium was studied by means of double-barrelled pH-selective microelectrodes. Transient changes in the intracellular pH were monitored in response to abrupt changes in the Na+ concentration on the retinal side of the epithelium. 2. The experiments were performed as follows. The Na(+)-HCO3- co-transport was inhibited by perfusing the retinal side of the epithelium with a Na(+)-free solution. The co-transport was then stimulated by changing the perfusate from the Na(+)-free solution to a solution which contained from 5 to 110 mM-Na+. The resulting inward Na(+)-HCO3- co-transport produced an intracellular alkalinization, the initial rate of which was used to calculate the initial rate of Na(+)-HCO3- co-transport, JHCO3-. 3. The Na+ dependence of the Na(+)-HCO3- co-transport was studied at two different values of extracellular pH (7.40 and 7.10), at constant extracellular HCO3- concentration (27.5 mM) and at two different extracellular HCO3- concentrations (27.5 mM and 55 mM) at constant extracellular pH (7.40). In these experiments, the calculated values of JHCO3- followed single Michaelis-Menten kinetics with respect to the extracellular Na+ concentration. 4. The data are consistent with a model in which the co-transporter has a single binding site for the Na+ ion with an apparent affinity constant (apparent Km) of 37 mM. The apparent affinity constant for Na+ was independent of the extracellular concentration of CO3(2-) in the range of 16-65 microM, and of the extracellular HCO3- concentration in the range 27.5-55 mM. 5. The NaCO3- ion-pair hypothesis, in which sodium binds to the co-transporter and is translocated across the cell membrane as the NaCO3- ion pair, was analysed. For stoichiometries 1:2 and 1:3 of the Na(+)-HCO3- co-transport, the NaCO3- ion-pair hypothesis was found incompatible with the data. 6. The intracellular buffer capacity as measured by the CO2 method was

  3. The NA49 large acceptance hadron detector

    NASA Astrophysics Data System (ADS)

    Afanasiev, S.; Alber, T.; Appelshäuser, H.; Bächler, J.; Barna, D.; Barnby, L. S.; Bartke, J.; Barton, R. A.; Betev, L.; Bialkowska, H.; Bieser, F.; Billmeier, A.; Blyth, C. O.; Bock, R.; Bormann, C.; Bracinik, J.; Brady, F. P.; Brockmann, R.; Brun, R.; Buncic, P.; Caines, H. L.; Cebra, D.; Cooper, G. E.; Cramer, J. G.; Csato, P.; Cyprian, M.; Dunn, J.; Eckardt, V.; Eckhardt, F.; Empl, T.; Eschke, J.; Ferguson, M. I.; Fessler, H.; Fischer, H. G.; Flierl, D.; Fodor, Z.; Frankenfeld, U.; Foka, P.; Freund, P.; Friese, V.; Ftacnik, J.; Fuchs, M.; Gabler, F.; Gal, J.; Ganz, R.; Gaździcki, M.; Gładysz, E.; Grebieszkow, J.; Günther, J.; Harris, J. W.; Hegyi, S.; Henkel, T.; Hill, L. A.; Hlinka, V.; Huang, I.; Hümmler, H.; Igo, G.; Irmscher, D.; Ivanov, M.; Janik, R.; Jacobs, P.; Jones, P. G.; Kadija, K.; Kolesnikov, V. I.; Kowalski, M.; Lasiuk, B.; Lévai, P.; Liebicher, K.; Lynen, U.; Malakhov, A. I.; Margetis, S.; Markert, C.; Marks, C.; Mayes, B.; Melkumov, G. L.; Mock, A.; Molnár, J.; Nelson, J. M.; Oldenburg, M.; Odyniec, G.; Palla, G.; Panagiotou, A. D.; Pestov, Y.; Petridis, A.; Pikna, M.; Pimpl, W.; Pinsky, L.; Piper, A.; Porter, R. J.; Poskanzer, A. M.; Poziombka, S.; Prindle, D. J.; Pühlhofer, F.; Rauch, W.; Reid, J. G.; Renfordt, R.; Retyk, W.; Ritter, H. G.; Röhrich, D.; Roland, C.; Roland, G.; Rudolph, H.; Rybicki, A.; Sammer, T.; Sandoval, A.; Sann, H.; Schäfer, E.; Schmidt, R.; Schmischke, D.; Schmitz, N.; Schönfelder, S.; Semenov, A. Yu.; Seyboth, J.; Seyboth, P.; Seyerlein, J.; Sikler, F.; Sitar, B.; Skrzypczak, E.; Squier, G. T. A.; Stelzer, H.; Stock, R.; Strmen, P.; Ströbele, H.; Struck, C.; Susa, T.; Szarka, I.; Szentpetery, I.; Szymański, P.; Sziklai, J.; Toy, M.; Trainor, T. A.; Trentalange, S.; Ullrich, T.; Vassiliou, M.; Veres, G.; Vesztergombi, G.; Vranic, D.; Wang, F. Q.; Weerasundara, D. D.; Wenig, S.; Whitten, C.; Wieman, H.; Wienold, T.; Wood, L.; Yates, T. A.; Zimanyi, J.; Zhu, X.-Z.; Zybert, R.

    1999-07-01

    The NA49 detector is a wide acceptance spectrometer for the study of hadron production in p+p, p+A, and A+A collisions at the CERN SPS. The main components are 4 large-volume TPCs for tracking and particle identification via d E/d x. TOF scintillator arrays complement particle identification. Calorimeters for transverse energy determination and triggering, a detector for centrality selection in p+A collisions, and beam definition detectors complete the set-up. A description of all detector components is given with emphasis on new technical realizations. Performance and operational experience are discussed in particular with respect to the high track density environment of central Pb+Pb collisions.

  4. Pion and kaon freezeout in NA44

    SciTech Connect

    NA44 Collaboration

    1994-12-01

    The NA44 spectrometer is optimized for the study of single and two-particle particle spectra near mid-rapidity for transverse momenta below {approx} 1 GeV/c. A large fraction of all pairs in the spectrometer`s acceptance are at low relative momenta, resulting in small statistical uncertainties on the extracted size parameters. In addition, the spectrometer`s clean particle identification allows the authors to measure correlation functions for pions, kaons, and protons. This contribution will concentrate on the source size parameters determined from pion and kaon correlation functions. These size parameters will be compared to calculations from the RQMD event generator and also interpreted in the context of a hydrodynamic model. Finally, the measured single particle spectra will be examined from the viewpoint of hydrodynamics.

  5. Na-Zn liquid metal battery

    NASA Astrophysics Data System (ADS)

    Xu, Junli; Kjos, Ole Sigmund; Osen, Karen Sende; Martinez, Ana Maria; Kongstein, Ole Edvard; Haarberg, Geir Martin

    2016-11-01

    A new kind of membrane free liquid metal battery was developed. The battery employs liquid sodium and zinc as electrodes both in liquid state, and NaCl-CaCl2 molten salts as electrolyte. The discharge flat voltage is in the range of about 1.4 V-1.8 V, and the cycle efficiency achieved is about 90% at low discharge current densities (below 40 mA cm-2). Moreover, this battery can also be charged and discharged at high current density with good performance. The discharge flat voltage is above 1.1 V when it is discharged at 100 mA cm-2, while it is about 0.8 V with 100% cycle efficiency when it is discharged at 200 mA cm-2. Compared to other reported liquid metal battery, this battery has lower cost, which suggests broad application prospect in energy storage systems for power grid.

  6. Study of OSL in NaF: Ca,Cu

    NASA Astrophysics Data System (ADS)

    More, Y. K.; Wankhede, S. P.; Moharil, S. V.

    2013-06-01

    Sodium Fluoride containing Cu+ ions was prepared by R.A.P. followed by melt-quenching technique. Results on photo, thermo and optically stimulated luminescence in NaF:Ca,Cu are reported. OSL sensitivity of NaF:Ca,Cu is approximately 2 times than that of standard phosphor LMP. The rate of OSL depletion for 90% decay for NaF:Ca,Cu is 0.3 times as that of OSL phosphor LMP. NaF:Ca,Cu thus deserves much more attention than it has received up till now.

  7. New solid conductors of Na/+/ and K/+/ ions

    NASA Technical Reports Server (NTRS)

    Singer, J.; Fielder, W. L.; Kautz, H. E.; Fordyce, J. S.

    1976-01-01

    About 40 structure types for solid conductors of Na(+) and K(+) ions are surveyed. Five compounds in three structure types are discovered to be good solid conductors of alkali metal ions, capable of ion transport with conductivities in the vicinity of 0.00001/ohm-cm at 25 C. These compounds are a bcc form of NaSbO3, an orthorhombic layer structure of the composition 2M2O.3Nb2O5 with M equal to Na or K, and the Na pyrochlores NaTa2O5F and NaTaWO6. Ion exchange is required to produce each of these Na compounds. Only the 2K2O.3Nb2O5 can so far be synthesized directly from the oxides and thus is the only one which can be sintered readily. The niobate is about as good a conductor of K(+) ion as is K-beta alumina. The NaSbO3 compares well with Na beta at 280 C. A number of phase diagrams are developed.

  8. The Physiological Relevance of Na+-Coupled K+-Transport.

    PubMed Central

    Maathuis, FJM.; Verlin, D.; Smith, F. A.; Sanders, D.; Fernandez, J. A.; Walker, N. A.

    1996-01-01

    Plant roots utilize at least two distinct pathways with high and low affinities to accumulate K+. The system for high-affinity K+ uptake, which takes place against the electrochemical K+ gradient, requires direct energization. Energization of K+ uptake via Na+ coupling has been observed in algae and was recently proposed as a mechanism for K+ uptake in wheat (Triticum aestivum L.). To investigate whether Na+ coupling has general physiological relevance in energizing K+ transport, we screened a number of species, including Arabidopsis thaliana L. Heynh. ecotype Columbia, wheat, and barley (Hordeum vulgare L.), for the presence of Na+-coupled K+ uptake. Rb+-flux analysis and electrophysiological K+-transport assays were performed in the presence and absence of Na+ and provided evidence for a coupling between K+ and Na+ transport in several aquatic species. However, all investigated terrestrial species were able to sustain growth and K+ uptake in the absence of Na+. Furthermore, the addition of Na+ was either without effect or inhibited K+ absorption. The latter characteristic was independent of growth conditions with respect to Na+ status and pH. Our results suggest that in terrestrial species Na+-coupled K+ transport has no or limited physiological relevance, whereas in certain aquatic angiosperms and algae this type of secondary transport energization plays a significant role. PMID:12226467

  9. Influenza virus neuraminidase (NA): a target for antivirals and vaccines.

    PubMed

    Jagadesh, Anitha; Salam, Abdul Ajees Abdul; Mudgal, Piya Paul; Arunkumar, Govindakarnavar

    2016-08-01

    Influenza, the most common infectious disease, poses a great threat to human health because of its highly contagious nature and fast transmissibility, often leading to high morbidity and mortality. Effective vaccination strategies may aid in the prevention and control of recurring epidemics and pandemics associated with this infectious disease. However, antigenic shifts and drifts are major concerns with influenza virus, requiring effective global monitoring and updating of vaccines. Current vaccines are standardized primarily based on the amount of hemagglutinin, a major surface antigen, which chiefly constitutes these preparations along with the varying amounts of neuraminidase (NA). Anti-influenza drugs targeting the active site of NA have been in use for more than a decade now. However, NA has not been approved as an effective antigenic component of the influenza vaccine because of standardization issues. Although some studies have suggested that NA antibodies are able to reduce the severity of the disease and induce a long-term and cross-protective immunity, a few major scientific issues need to be addressed prior to launching NA-based vaccines. Interestingly, an increasing number of studies have shown NA to be a promising target for future influenza vaccines. This review is an attempt to consolidate studies that reflect the strength of NA as a suitable vaccine target. The studies discussed in this article highlight NA as a potential influenza vaccine candidate and support taking the process of developing NA vaccines to the next stage.

  10. Tuning NaYF4 Nanoparticles through Alkaline Earth Doping

    PubMed Central

    Chen, Xian; Peng, Dengfeng; Wang, Feng

    2013-01-01

    Phase and size of lanthanide-doped nanoparticles are the most important characteristics that dictate optical properties of these nanoparticles and affect their technological applications. Herein, we present a systematic study to examine the effect of alkaline earth doping on the formation of NaYF4 upconversion nanoparticles. We show that alkaline earth doping has a dual function of tuning particle size of hexagonal phase NaYF4 nanoparticles and stabilizing cubic phase NaYF4 nanoparticles depending on composition and concentration of the dopant ions. The study described here represents a facile and general strategy to tuning the properties of NaYF4 upconversion nanoparticles. PMID:28348353

  11. Kaolin-based geopolymers with various NaOH concentrations

    NASA Astrophysics Data System (ADS)

    Heah, C. Y.; Kamarudin, H.; Mustafa Al Bakri, A. M.; Bnhussain, M.; Luqman, M.; Khairul Nizar, I.; Ruzaidi, C. M.; Liew, Y. M.

    2013-03-01

    Kaolin geopolymers were produced by the alkali-activation of kaolin with an activator solution (a mixture of NaOH and sodium silicate solutions). The NaOH solution was prepared at a concentration of 6-14 mol/L and was mixed with the sodium silicate solution at a Na2SiO3/NaOH mass ratio of 0.24 to prepare an activator solution. The kaolin-to-activator solution mass ratio used was 0.80. This paper aimed to analyze the effect of NaOH concentration on the compressive strength of kaolin geopolymers at 80°C for 1, 2, and 3 d. Kaolin geopolymers were stable in water, and strength results showed that the kaolin binder had adequate compressive strength with 12 mol/L of NaOH concentration. When the NaOH concentration increased, the SiO2/Na2O decreased. The increased Na2O content enhanced the dissolution of kaolin as shown in X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analyses. However, excess in this content was not beneficial for the strength development of kaolin geopolymers. In addition, there was the formation of more geopolymeric gel in 12 mol/L samples. The XRD pattern of the samples showed a higher amorphous content and a more geopolymer bonding existed as proved by FTIR analysis.

  12. Transcriptional regulators of Na,K-ATPase subunits

    PubMed Central

    Li, Zhiqin; Langhans, Sigrid A.

    2015-01-01

    The Na,K-ATPase classically serves as an ion pump creating an electrochemical gradient across the plasma membrane that is essential for transepithelial transport, nutrient uptake and membrane potential. In addition, Na,K-ATPase also functions as a receptor, a signal transducer and a cell adhesion molecule. With such diverse roles, it is understandable that the Na,K-ATPase subunits, the catalytic α-subunit, the β-subunit and the FXYD proteins, are controlled extensively during development and to accommodate physiological needs. The spatial and temporal expression of Na,K-ATPase is partially regulated at the transcriptional level. Numerous transcription factors, hormones, growth factors, lipids, and extracellular stimuli modulate the transcription of the Na,K-ATPase subunits. Moreover, epigenetic mechanisms also contribute to the regulation of Na,K-ATPase expression. With the ever growing knowledge about diseases associated with the malfunction of Na,K-ATPase, this review aims at summarizing the best-characterized transcription regulators that modulate Na,K-ATPase subunit levels. As abnormal expression of Na,K-ATPase subunits has been observed in many carcinoma, we will also discuss transcription factors that are associated with epithelial-mesenchymal transition, a crucial step in the progression of many tumors to malignant disease. PMID:26579519

  13. Mercury's Na Exosphere from MESSENGER Data

    NASA Technical Reports Server (NTRS)

    Killen, Rosemary M.; Burger, M. H.; Cassidy, T. A.; Sarantos, M.; Vervack, R. J.; McClintock, W. El; Merkel, A. W.; Sprague, A. L.; Solomon, S. C.

    2012-01-01

    MESSENGER entered orbit about Mercury on March 18, 2011. Since then, the Ultraviolet and Visible Spectrometer (UWS) channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer (MASCS) has been observing Mercury's exosphere nearly continuously. Daily measurements of Na brightness were fitted with non-uniform exospheric models. With Monte Carlo sampling we traced the trajectories of a representative number of test particles, generally one million per run per source process, until photoionization, escape from the gravitational well, or permanent sticking at the surface removed the atom from the simulation. Atoms were assumed to partially thermally accommodate on each encounter with the surface with accommodation coefficient 0.25. Runs for different assumed source processes are run separately, scaled and co-added. Once these model results were saved onto a 3D grid, we ran lines of sight from the MESSENGER spacecraft :0 infinity using the SPICE kernels and we computed brightness integrals. Note that only particles that contribute to the measurement can be constrained with our method. Atoms and molecules produced on the nightside must escape the shadow in order to scatter light if the excitation process is resonant-light scattering, as assumed here. The aggregate distribution of Na atoms fits a 1200 K gas, with a PSD distribution, along with a hotter component. Our models constrain the hot component, assumed to be impact vaporization, to be emitted with a 2500 K Maxwellian. Most orbits show a dawnside enhancement in the hot component broadly spread over the leading hemisphere. However, on some dates there is no dawn/dusk asymmetry. The portion of the hot/cold source appears to be highly variable.

  14. Mercury's Na Exosphere from MESSENGER data

    NASA Astrophysics Data System (ADS)

    Killen, Rosemary M.; Burger, M. H.; Cassidy, T. A.; Sarantos, M.; Vervack, R. J.; McClintock, W. E.; Merkel, A. W.; Sprague, A. L.; Solomon, S. C.

    2012-10-01

    MESSENGER entered orbit about Mercury on March 18, 2011. Since then, the Ultraviolet and Visible Spectrometer (UVVS) channel of MESSENGER's Mercury Atmospheric and Surface Composition Spectrometer (MASCS) has been observing Mercury's exosphere nearly continuously. Daily measurements of Na brightness were fitted with non-uniform exospheric models. With Monte Carlo sampling we traced the trajectories of a representative number of test particles, generally one million per run per source process, until photoionization, escape from the gravitational well, or permanent sticking at the surface removed the atom from the simulation. Atoms were assumed to partially thermally accommodate on each encounter with the surface with accommodation coefficient 0.25. Runs for different assumed source processes are run separately, scaled and co-added. Once these model results were saved onto a 3D grid, we ran lines of sight from the MESSENGER spacecraft to infinity using the SPICE kernels and we computed brightness integrals. Note that only particles that contribute to the measurement can be constrained with our method. Atoms and molecules produced on the nightside must escape the shadow in order to scatter light if the excitation process is resonant-light scattering, as assumed here. The aggregate distribution of Na atoms fits a 1200 K gas, with a PSD distribution, along with a hotter component. Our models constrain the hot component, assumed to be impact vaporization, to be emitted with a 2500 K Maxwellian. Most orbits show a dawnside enhancement in the hot component broadly spread over the leading hemisphere. However, on some dates there is no dawn/dusk asymmetry. The hot portion of the source appears to be highly variable. The authors acknowledge support from NASA through the MESSENGER Participating Scientist Program and Planetary Atmospheres research grants.

  15. Attenuation of Na/K-ATPase Mediated Oxidant Amplification with pNaKtide Ameliorates Experimental Uremic Cardiomyopathy

    PubMed Central

    Liu, Jiang; Tian, Jiang; Chaudhry, Muhammad; Maxwell, Kyle; Yan, Yanling; Wang, Xiaoliang; Shah, Preeya T.; Khawaja, Asad A.; Martin, Rebecca; Robinette, Tylor J.; El-Hamdani, Adee; Dodrill, Michael W.; Sodhi, Komal; Drummond, Christopher A.; Haller, Steven T.; Kennedy, David J.; Abraham, Nader G.; Xie, Zijian; Shapiro, Joseph I.

    2016-01-01

    We have previously reported that the sodium potassium adenosine triphosphatase (Na/K-ATPase) can effect the amplification of reactive oxygen species. In this study, we examined whether attenuation of oxidant stress by antagonism of Na/K-ATPase oxidant amplification might ameliorate experimental uremic cardiomyopathy induced by partial nephrectomy (PNx). PNx induced the development of cardiac morphological and biochemical changes consistent with human uremic cardiomyopathy. Both inhibition of Na/K-ATPase oxidant amplification with pNaKtide and induction of heme oxygenase-1 (HO-1) with cobalt protoporphyrin (CoPP) markedly attenuated the development of phenotypical features of uremic cardiomyopathy. In a reversal study, administration of pNaKtide after the induction of uremic cardiomyopathy reversed many of the phenotypical features. Attenuation of Na/K-ATPase oxidant amplification may be a potential strategy for clinical therapy of this disorder. PMID:27698370

  16. Scintillation efficiency measurement of Na recoils in NaI(Tl) below the DAMA/LIBRA energy threshold

    NASA Astrophysics Data System (ADS)

    Xu, Jingke; Shields, Emily; Calaprice, Frank; Westerdale, Shawn; Froborg, Francis; Suerfu, Burkhant; Alexander, Thomas; Aprahamian, Ani; Back, Henning O.; Casarella, Clark; Fang, Xiao; Gupta, Yogesh K.; Ianni, Aldo; Lamere, Edward; Lippincott, W. Hugh; Liu, Qian; Lyons, Stephanie; Siegl, Kevin; Smith, Mallory; Tan, Wanpeng; Kolk, Bryant Vande

    2015-07-01

    The dark matter interpretation of the DAMA modulation signal depends on the NaI(Tl) scintillation efficiency of nuclear recoils. Previous measurements for Na recoils have large discrepancies, especially in the DAMA/LIBRA modulation energy region. We report a quenching effect measurement of Na recoils in NaI(Tl) from 3 to 52 keVnr, covering the whole DAMA/LIBRA energy region for dark matter-Na scattering interpretations. By using a low-energy, pulsed neutron beam, a double time-of-flight technique, and pulse-shape discrimination methods, we obtained the most accurate measurement of this kind for NaI(Tl) to date. The results differ significantly from the DAMA reported values at low energies but fall between the other previous measurements. We present the implications of the new quenching results for the dark matter interpretation of the DAMA modulation signal.

  17. Decomposition reactions for NaAl H4 , Na3 Al H6 , and NaH: First-principles study

    NASA Astrophysics Data System (ADS)

    Ke, Xuezhi; Tanaka, Isao

    2005-01-01

    The electronic properties and lattice dynamics of the sodium alanate phases have been studied by the density functional calculations. The phases include NaAlH4 (space group, I41/a ), Na3AlH6 (space group, P21/n ), and NaH (space group, Fm-3m ). The electronic properties are discussed on the basis of the electronic band structures, the atomic charges, the bond overlap population analysis, and the Born effective charges. The phonon dispersion relations and phonon density of states (DOS) of the phases are calculated by a direct force-constant method. Within the quasiharmonic approximation, the calculated thermodynamic functions including the heat capacity, the vibrational enthalpy, and the vibrational entropy are in good agreement with experimental values. Three decomposition reactions are studied based on the thermodynamic functions. The reactions are (1) NaAlH4→(1)/(3)Na3AlH6+(2)/(3)Al+H2 , (2) (1)/(3)Na3AlH6→NaH+(1)/(3)Al+(1)/(2)H2 , and (3) NaH→Na+(1)/(2)H2 . The reactions (1), (2), and (3) are predicted to take place at 285, 390, and 726K , respectively, which are in good agreement with the experiment (353, 423, and 698K , respectively). The individual contributions to the reactions including the enthalpy and entropy are investigated. We found that the enthalpy for the reaction is almost constant, and the net entropy contribution ( TΔS ) to the reaction is approximately equal to the entropy contribution of the H2 gas molecule (produced in that reaction).

  18. RNA adducts with Na 2SeO 4 and Na 2SeO 3 - Stability and structural features

    NASA Astrophysics Data System (ADS)

    Nafisi, Shohreh; Manouchehri, Firouzeh; Montazeri, Maryam

    2011-12-01

    Selenium compounds are widely available in dietary supplements and have been extensively studied for their antioxidant and anticancer properties. Low blood Se levels were found to be associated with an increased incidence and mortality from various types of cancers. Although many in vivo and clinical trials have been conducted using these compounds, their biochemical and chemical mechanisms of efficacy are the focus of much current research. This study was designed to examine the interaction of Na 2SeO 4 and Na 2SeO 3 with RNA in aqueous solution at physiological conditions, using a constant RNA concentration (6.25 mM) and various sodium selenate and sodium selenite/polynucleotide (phosphate) ratios of 1/80, 1/40, 1/20, 1/10, 1/5, 1/2 and 1/1. Fourier transform infrared, UV-Visible spectroscopic methods were used to determine the drug binding modes, the binding constants, and the stability of Na 2SeO 4 and Na 2SeO 3-RNA complexes in aqueous solution. Spectroscopic evidence showed that Na 2SeO 4 and Na 2SeO 3 bind to the major and minor grooves of RNA ( via G, A and U bases) with some degree of the Se-phosphate (PO 2) interaction for both compounds with overall binding constants of K(Na 2SeO 4-RNA) = 8.34 × 10 3 and K(Na 2SeO 3-RNA) = 4.57 × 10 3 M -1. The order of selenium salts-biopolymer stability was Na 2SeO 4-RNA > Na 2SeO 3-RNA. RNA aggregations occurred at higher selenium concentrations. No biopolymer conformational changes were observed upon Na 2SeO 4 and Na 2SeO 3 interactions, while RNA remains in the A-family structure.

  19. A 23Na magic angle spinning nuclear magnetic resonance, XANES, and high-temperature X-ray diffraction study of NaUO3, Na4UO5, and Na2U2O7.

    PubMed

    Smith, A L; Raison, P E; Martel, L; Charpentier, T; Farnan, I; Prieur, D; Hennig, C; Scheinost, A C; Konings, R J M; Cheetham, A K

    2014-01-06

    The valence state of uranium has been confirmed for the three sodium uranates NaU(V)O3/[Rn](5f(1)), Na4U(VI)O5/[Rn](5f(0)), and Na2U(VI)2O7/[Rn](5f(0)), using X-ray absorption near-edge structure (XANES) spectroscopy. Solid-state (23)Na magic angle spinning nuclear magnetic resonance (MAS NMR) measurements have been performed for the first time, yielding chemical shifts at -29.1 (NaUO3), 15.1 (Na4UO5), and -14.1 and -19 ppm (Na1 8-fold coordinated and Na2 7-fold coordinated in Na2U2O7), respectively. The [Rn]5f(1) electronic structure of uranium in NaUO3 causes a paramagnetic shift in comparison to Na4UO5 and Na2U2O7, where the electronic structure is [Rn]5f(0). A (23)Na multi quantum magic angle spinning (MQMAS) study on Na2U2O7 has confirmed a monoclinic rather than rhombohedral structure with evidence for two distinct Na sites. DFT calculations of the NMR parameters on the nonmagnetic compounds Na4UO5 and Na2U2O7 have permitted the differentiation between the two Na sites of the Na2U2O7 structure. The linear thermal expansion coefficients of all three compounds have been determined using high-temperature X-ray diffraction: αa = 22.7 × 10(-6) K(-1), αb = 12.9 × 10(-6) K(-1), αc = 16.2 × 10(-6) K(-1), and αvol = 52.8 × 10(-6) K(-1) for NaUO3 in the range 298-1273 K; αa = 37.1 × 10(-6) K(-1), αc = 6.2 × 10(-6) K(-1), and αvol = 81.8 × 10(-6) K(-1) for Na4UO5 in the range 298-1073 K; αa = 6.7 × 10(-6) K(-1), αb = 14.4 × 10(-6) K(-1), αc = 26.8 × 10(-6) K(-1), αβ = -7.8 × 10(-6) K(-1), and αvol = -217.6 × 10(-6) K(-1) for Na2U2O7 in the range 298-573 K. The α to β phase transition reported for the last compound above about 600 K was not observed in the present studies, either by high-temperature X-ray diffraction or by differential scanning calorimetry.

  20. Limitation of heavy-ion fusion: Fusion of aligned /sup 23/Na with /sup 23/Na

    SciTech Connect

    Blatt, K.; Becker, K.; Heck, B.; Jaensch, H.; Leucker, H.; Fick, D.; Chacekaplar, R.; Butsch, R.; Kraemer, D.; Moebius, K.h.

    1986-08-18

    The excitation function for fusion of /sup 23/Na with /sup 23/Na was measured in the energy range 40 less than or equal to E/sub c.m./less than or equal to 88.5 MeV. Additionally the tensor analyzing power T/sub 20/ was determined to be T/sub 20/ = -0.0060 +- 0.0125 at E/sub c.m./ = 85 MeV. The results are discussed in terms of an entrance-channel versus a compound-nucleus model for the observed limitation of fusion. A typical entrance-channel model, the surface-friction model, which is able to describe all fusion excitation functions leading to /sup 46/Ti, fails to reproduce the observed value of T/sub 20/. The data are consistent, on the other hand, with the compound-nucleus interpretation.

  1. Path integral study of the correlated electronic states of Na4-Na6

    NASA Astrophysics Data System (ADS)

    Hall, Randall W.

    1990-12-01

    Feynman's path integral formulation of quantum mechanics is used to study the correlated electronic states of Na4-Na6. Two types of simulations are performed: in the first, the nuclei are allowed to move at finite temperature in order to find the most stable geometries. In agreement with previous calculations, we find that planar structures are the most stable and that there is significant vibrational amplitude at finite temperatures, indicating that the Born-Oppenheimer surface is relatively flat. In the second type of simulation, the nuclei are held fixed at symmetric and asymmetric geometries and the correlated electron density is found. Our results show that the electrons are localized, rather than delocalized as previous workers have concluded from examination of the single-particle orbitals. We find that the best picture of these clusters is that they contain three-center, two-electron bonds.

  2. Expression of diverse Na+ channel messenger RNAs in rat myocardium. Evidence for a cardiac-specific Na+ channel.

    PubMed Central

    Sills, M N; Xu, Y C; Baracchini, E; Goodman, R H; Cooperman, S S; Mandel, G; Chien, K R

    1989-01-01

    This study examined the diversity of Na+ channel gene expression in intact cardiac tissue and purified myocardial cells. The screening of neonatal rat myocardial cell cDNA libraries with a conserved rat brain Na+ channel cDNA probe, resulted in the isolation and characterization of a putative rat cardiac Na+ channel cDNA probe (pCSC-1). The deduced amino acid sequence of pCSC-1 displayed a striking degree of homology with the eel, rat brain-1, and rat brain-2 Na+ channel, thereby identifying pCSC-1 as a related member of the family of Na+ channel genes. Northern blot analysis revealed the expression of a 7-kb CSC-1 transcript in rat cardiac tissue and purified myocardial cells, but little or no detectable expression of CSC-1 in rat brain, skeletal muscle, denervated skeletal muscle, or liver. Using RNase protection and Northern blot hybridization with specific rat brain Na+ channel gene probes, expression of the rat brain-1 Na+ channel was observed in rat myocardium, but no detectable expression of the rat brain-2 gene was found. This study provides evidence for the expression of diverse Na+ channel mRNAs in rat myocardium and presents the initial characterization of a new, related member of the family of Na+ channel genes, which appears to be expressed in a cardiac-specific manner. Images PMID:2544627

  3. Estimating the hydrogen ion concentration in concentrated NaCl and Na{sub 2}SO{sub 4} electrolytes

    SciTech Connect

    Rai, D.; Felmy, A.R.; Juracich, S.P.; Rao, F.

    1995-06-01

    Combination glass electrodes were tested for determining H{sup +} concentrations in concentrated pure and mixed NaCl and Na{sub 2}SO{sub 4} solutions, as well as natural brine systems. NaCl, Na{sub 2}SO{sub 4}, and mixtures of NaCl and Na{sub 2}SO{sub 4} solutions were analyzed. Correction factors for estimating pC{sub H}{sup +} (negative logarithm of H{sup +} concentration) were determined from measured/observed pH values. Required Gran-type titrations were done with HCl and/or NaOH. The titration method is described and a step-by-step procedure provided; it has been used previously for determining pC{sub H}{sup +} values of synthetic chloride-dominated brines. Precautions are required to determine correction factors for electrolytes that react with H{sup +} or OH{sup {minus}} [sulfate brines for titration with acid; magnesium brines for titration with base because of precipitation of Mg(OH)2]. Correction factors A (pC{sub H}{sup +} = pH{sub ob} + A) from HCl titrations were similar to those from NaOH titrations where the concentration of free H{sup +} was calculated using a thermodynamic model. These values should be applicable to solns with a very large range in measured pH values (2 to 12). Because a large number of solns were titrated with HCl and the A values are similar for HCl and NaOH titrations, the A values for NaCl and Na2SO4 solns were fit as a function of molality to allow extrapolation. For NaCl solns 0 to 6.0 M, A can be obtained by multiplying the molality by 0.159. For Na2SO4 solns 0 to 2.0 M, the values of A can be obtained from (0.221 {minus} 0.549X + 0.201X{sup 2}), where X is the molality of Na{sub 2}SO{sub 4}. Orion-Ross electrode evaluations indicated that the A values did not differ significantly for different electrodes. Results suggest that the data in this report can be used to estimate A values for different NaCl and Na{sub 2}SO{sub 4} solns even for noncalibrated electrodes.

  4. Temperature-dependent formation of NaCl dihydrate in levitated NaCl and sea salt aerosol particles.

    PubMed

    Peckhaus, Andreas; Kiselev, Alexei; Wagner, Robert; Duft, Denis; Leisner, Thomas

    2016-12-28

    Recent laboratory studies indicate that the hydrated form of crystalline NaCl is potentially important for atmospheric processes involving depositional ice nucleation on NaCl dihydrate particles under cirrus cloud conditions. However, recent experimental studies reported a strong discrepancy between the temperature intervals where the efflorescence of NaCl dihydrate has been observed. Here we report the measurements of the volume specific nucleation rate of crystalline NaCl in the aqueous solution droplets of pure NaCl suspended in an electrodynamic balance at constant temperature and humidity in the range from 250 K to 241 K. Based on these measurements, we derive the interfacial energy of crystalline NaCl dihydrate in a supersaturated NaCl solution and determined its temperature dependence. Taking into account both temperature and concentration dependence of nucleation rate coefficients, we explain the difference in the observed fractions of NaCl dihydrate reported in the previous studies. Applying the heterogeneous classical nucleation theory model, we have been able to reproduce the 5 K shift of the NaCl dihydrate efflorescence curve observed for the sea salt aerosol particles, assuming the presence of super-micron solid inclusions (hypothetically gypsum or hemihydrate of CaSO4). These results support the notion that the phase transitions in microscopic droplets of supersaturated solution should be interpreted by accounting for the stochastic nature of homogeneous and heterogeneous nucleation and cannot be understood on the ground of bulk phase diagrams alone.

  5. Na+ and K+ levels in living cells: do they depend on the rate of outward transport of Na+?

    PubMed

    Ling, G N; Ochsenfeld, M M

    1976-01-01

    At 25 degrees C, frog sartorius muslces rapidly gained Na+ and lost K+ in iodoacetamide and pure nitrogen. Beginning at normal levels, the concentrations of these ions in the cells reached those in the surrounding Ringer solution in 140 min. Yet during that time the Na+ efflux rate showed no sign of the slowing down demanded by Na-pump theory. The data support the view that maintenance and alterations of N1+ levels in frog muslce cells reflect adsorption on protein sites and the solubility property of bulk phase water and are independent of the rate at which Na+ leaves the cell surface.

  6. Kinetics and stoichiometry of coupled Na efflux and Ca influx (Na/Ca exchange) in barnacle muscle cells

    PubMed Central

    1989-01-01

    Coupled Na+ exit/Ca2+ entry (Na/Ca exchange operating in the Ca2+ influx mode) was studied in giant barnacle muscle cells by measuring 22Na+ efflux and 45Ca2+ influx in internally perfused, ATP-fueled cells in which the Na+ pump was poisoned by 0.1 mM ouabain. Internal free Ca2+, [Ca2+]i, was controlled with a Ca-EGTA buffering system containing 8 mM EGTA and varying amounts of Ca2+. Ca2+ sequestration in internal stores was inhibited with caffeine and a mitochondrial uncoupler (FCCP). To maximize conditions for Ca2+ influx mode Na/Ca exchange, and to eliminate tracer Na/Na exchange, all of the external Na+ in the standard Na+ sea water (NaSW) was replaced by Tris or Li+ (Tris-SW or LiSW, respectively). In both Na-free solutions an external Ca2+ (Cao)-dependent Na+ efflux was observed when [Ca2+]i was increased above 10(-8) M; this efflux was half-maximally activated by [Ca2+]i = 0.3 microM (LiSW) to 0.7 microM (Tris-SW). The Cao-dependent Na+ efflux was half-maximally activated by [Ca2+]o = 2.0 mM in LiSW and 7.2 mM in Tris-SW; at saturating [Ca2+]o, [Ca2+]i, and [Na+]i the maximal (calculated) Cao-dependent Na+ efflux was approximately 75 pmol#cm2.s. This efflux was inhibited by external Na+ and La3+ with IC50's of approximately 125 and 0.4 mM, respectively. A Nai-dependent Ca2+ influx was also observed in Tris-SW. This Ca2+ influx also required [Ca2+]i greater than 10(-8) M. Internal Ca2+ activated a Nai-independent Ca2+ influx from LiSW (tracer Ca/Ca exchange), but in Tris-SW virtually all of the Cai-activated Ca2+ influx was Nai-dependent (Na/Ca exchange). Half-maximal activation was observed with [Na+]i = 30 mM. The fact that internal Ca2+ activates both a Cao-dependent Na+ efflux and a Nai- dependent Ca2+ influx in Tris-SW implies that these two fluxes are coupled; the activating (intracellular) Ca2+ does not appear to be transported by the exchanger. The maximal (calculated) Nai-dependent Ca2+ influx was -25 pmol/cm2.s. At various [Na+]i between 6 and 106 m

  7. Clinical and therapeutic significance of the Na+,K+ pump*.

    PubMed

    Clausen, T

    1998-07-01

    1. The Na+,K+-ATPase or Na+,K+-pump, mediating the active transport of Na+ and K+, which was first identified 40 years ago, is a central target for acute and long-term regulation, as well as for therapeutic intervention. Acute stimulation of the Na+,K+-pump in skeletal muscle by insulin, catecholamines, beta2-agonists or theophylline increases the intracellular uptake of K+ and accounts for the hypokalaemia elicited by these agents. Conversely, digitalis intoxication elicits hyperkalaemia via acute inhibition of the Na+, K+-pump. 2. Simple and accurate methods have been developed for the quantification of the total concentration of Na+,K+-pumps in small (0.5-5 mg) fresh or frozen biopsies of human skeletal muscle, myocardium or other tissues. This has allowed the identification of several long-term regulatory changes in the concentration of this transport system in human tissues. In skeletal muscle, upregulation is induced by training, thyroid hormones or glucocorticoids. Downregulation is seen in hypothyroidism, cardiac insufficiency, myotonic dystrophy, McArdle disease, K+ deficiency and after muscle inactivity. 3. Since the skeletal muscles contain one of the major pools of Na+,K+-pumps, these changes are important for the ability to counterregulate the hyperkalaemia elicited by exercise or the ingestion of K+. Moreover, downregulation or inhibition of the Na+, K+-pumps in skeletal muscle interferes with contractile performance. Since digitalis glycosides bind to the Na+,K+-pump, the muscles constitute a large distribution volume for these agents and are therefore an important determinant for their plasma level. 4. In cardiac insufficiency, the decrease in the concentration of Na+, K+-pumps in the myocardium is over a wide range correlated to the concomitant reduction in ejection fraction. The regulatory and pathophysiological changes in the activity and concentration of Na+, K+-pumps are important for the contractile function of skeletal muscle and heart as

  8. North America and South America (NA-SA) neuropathy project.

    PubMed

    Pasnoor, Mamatha; Nascimento, Osvaldo J M; Trivedi, Jaya; Wolfe, Gil I; Nations, Sharon; Herbelin, Laura; de Freitas, M G; Quintanilha, Giseli; Khan, Saud; Dimachkie, Mazen; Barohn, Richard

    2013-08-01

    Peripheral neuropathy is a common neurological disorder. There may be important differences and similarities in the diagnosis of peripheral neuropathy between North America (NA) and South America (SA). Neuromuscular databases were searched for neuropathy diagnosis at two North American sites, University of Kansas Medical Center and University of Texas Southwestern Medical Center, and one South American site, Federal Fluminense University in Brazil. All patients were included into one of the six major categories: immune-mediated, diabetic, hereditary, infectious/inflammatory, systemic/metabolic/toxic (not diabetic) and cryptogenic. A comparison of the number of patients in each category was made between North America and South America databases. Total number of cases in North America was 1090 and in South America was 1034 [immune-mediated: NA 215 (19.7%), SA 191 (18%); diabetic: NA 148 (13.5%), SA 236 (23%); hereditary: NA 292 (26.7%), SA 103 (10%); infectious/inflammatory: NA 53 (4.8%), SA 141 (14%); systemic/metabolic/toxic: NA 71 (6.5%), SA 124 (12%); cryptogenic: NA 311 (28.5%), SA 239 (23%)]. Some specific neuropathy comparisons were hereditary neuropathies [Charcot-Marie-Tooth (CMT) cases] in NA 246/292 (84.2%) and SA 60/103 (58%); familial amyloid neuropathy in SA 31/103 (30%) and none in NA. Among infectious neuropathies, cases of human T-lymphotropic virus type 1 (HTLV-1) neuropathy in SA were 36/141(25%), Chagas disease in SA were 13/141(9%) and none for either in NA; cases of neuropathy due to leprosy in NA were 26/53 (49%) and in SA were 39/141(28%). South American tertiary care centers are more likely to see patients with infectious, diabetic and hereditary disorders such as familial amyloid neuropathies. North American tertiary centers are more likely to see patients with CMT. Immune neuropathies and cryptogenic neuropathies were seen equally in North America and South America.

  9. 33 CFR 147.833 - Na Kika FDS safety zone.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 33 Navigation and Navigable Waters 2 2010-07-01 2010-07-01 false Na Kika FDS safety zone. 147.833 Section 147.833 Navigation and Navigable Waters COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) OUTER CONTINENTAL SHELF ACTIVITIES SAFETY ZONES § 147.833 Na Kika FDS safety zone. (a) Description....

  10. Direct Measurement of {sup 21}Na+{alpha} Stellar Reaction

    SciTech Connect

    Binh, D. N.; Kubono, S.; Yamaguchi, H.; Hayakawa, S.; Hashimoto, T.; Kahl, D.; Teranishi, T.; Iwasa, N.; Kume, N.; Kato, S.; Khiem, L. H.; Tho, N. T.; Wakabayashi, Y.

    2010-08-12

    The measurement of the resonant alpha scattering and the {sup 21}Na({alpha}, p) reaction were performed for the first time in inverse kinematics with the thick target method using a {sup 21}Na radioisotope (RI) beam. This paper reports the current result of alpha scattering measurement and its astrophysics implication.

  11. Naïve Bayes classification in R

    PubMed Central

    2016-01-01

    Naïve Bayes classification is a kind of simple probabilistic classification methods based on Bayes’ theorem with the assumption of independence between features. The model is trained on training dataset to make predictions by predict() function. This article introduces two functions naiveBayes() and train() for the performance of Naïve Bayes classification. PMID:27429967

  12. Resurgent current of voltage-gated Na+ channels

    PubMed Central

    Lewis, Amanda H; Raman, Indira M

    2014-01-01

    Resurgent Na+ current results from a distinctive form of Na+ channel gating, originally identified in cerebellar Purkinje neurons. In these neurons, the tetrodotoxin-sensitive voltage-gated Na+ channels responsible for action potential firing have specialized mechanisms that reduce the likelihood that they accumulate in fast inactivated states, thereby shortening refractory periods and permitting rapid, repetitive, and/or burst firing. Under voltage clamp, step depolarizations evoke transient Na+ currents that rapidly activate and quickly decay, and step repolarizations elicit slower channel reopening, or a ‘resurgent’ current. The generation of resurgent current depends on a factor in the Na+ channel complex, probably a subunit such as NaVβ4 (Scn4b), which blocks open Na+ channels at positive voltages, competing with the fast inactivation gate, and unblocks at negative voltages, permitting recovery from an open channel block along with a flow of current. Following its initial discovery, resurgent Na+ current has been found in nearly 20 types of neurons. Emerging research suggests that resurgent current is preferentially increased in a variety of clinical conditions associated with altered cellular excitability. Here we review the biophysical, molecular and structural mechanisms of resurgent current and their relation to the normal functions of excitable cells as well as pathophysiology. PMID:25172941

  13. Unidirectional Flux Balance of Monovalent Ions in Cells with Na/Na and Li/Na Exchange: Experimental and Computational Studies on Lymphoid U937 Cells

    PubMed Central

    Vereninov, Igor A.; Yurinskaya, Valentina E.; Model, Michael A.; Vereninov, Alexey A.

    2016-01-01

    Monovalent ion traffic across the cell membrane occurs via various pathways. Evaluation of individual fluxes in whole cell is hampered by their strong interdependence. This difficulty can be overcome by computational analysis of the whole cell flux balance. However, the previous computational studies disregarded ion movement of the self-exchange type. We have taken this exchange into account. The developed software allows determination of unidirectional fluxes of all monovalent ions via the major pathways both under the balanced state and during transient processes. We show how the problem of finding the rate coefficients can be solved by measurement of monovalent ion concentrations and some of the fluxes. Interdependence of fluxes due to the mandatory conditions of electroneutrality and osmotic balance and due to specific effects can be discriminated, enabling one to identify specific changes in ion transfer machinery under varied conditions. To test the effectiveness of the developed approach we made use of the fact that Li/Na exchange is known to be an analogue of the coupled Na/Na exchange. Thus, we compared the predicted and experimental data obtained on U937 cells under varied Li+ concentrations and following inhibition of the sodium pump with ouabain. We found that the coupled Na/Na exchange in U937 cells comprises a significant portion of the entire Na+ turnover. The data showed that the loading of the sodium pump by Li/Na exchange involved in the secondary active Li+ transport at 1–10 mM external Li+ is small. This result may be extrapolated to similar Li+ and Na+ flux relationships in erythrocytes and other cells in patients treated with Li+ in therapeutic doses. The developed computational approach is applicable for studying various cells and can be useful in education for demonstrating the effects of individual transporters and channels on ion gradients, cell water content and membrane potential. PMID:27159324

  14. Unidirectional Flux Balance of Monovalent Ions in Cells with Na/Na and Li/Na Exchange: Experimental and Computational Studies on Lymphoid U937 Cells.

    PubMed

    Vereninov, Igor A; Yurinskaya, Valentina E; Model, Michael A; Vereninov, Alexey A

    2016-01-01

    Monovalent ion traffic across the cell membrane occurs via various pathways. Evaluation of individual fluxes in whole cell is hampered by their strong interdependence. This difficulty can be overcome by computational analysis of the whole cell flux balance. However, the previous computational studies disregarded ion movement of the self-exchange type. We have taken this exchange into account. The developed software allows determination of unidirectional fluxes of all monovalent ions via the major pathways both under the balanced state and during transient processes. We show how the problem of finding the rate coefficients can be solved by measurement of monovalent ion concentrations and some of the fluxes. Interdependence of fluxes due to the mandatory conditions of electroneutrality and osmotic balance and due to specific effects can be discriminated, enabling one to identify specific changes in ion transfer machinery under varied conditions. To test the effectiveness of the developed approach we made use of the fact that Li/Na exchange is known to be an analogue of the coupled Na/Na exchange. Thus, we compared the predicted and experimental data obtained on U937 cells under varied Li+ concentrations and following inhibition of the sodium pump with ouabain. We found that the coupled Na/Na exchange in U937 cells comprises a significant portion of the entire Na+ turnover. The data showed that the loading of the sodium pump by Li/Na exchange involved in the secondary active Li+ transport at 1-10 mM external Li+ is small. This result may be extrapolated to similar Li+ and Na+ flux relationships in erythrocytes and other cells in patients treated with Li+ in therapeutic doses. The developed computational approach is applicable for studying various cells and can be useful in education for demonstrating the effects of individual transporters and channels on ion gradients, cell water content and membrane potential.

  15. Interplanetary dust distribution and temporal variability of Mercury's atmospheric Na

    NASA Astrophysics Data System (ADS)

    Kameda, Shingo; Yoshikawa, Ichiro; Kagitani, Masato; Okano, Shoichi

    2009-08-01

    The interplanetary dust (IPD) distribution in the inner solar system is not yet well understood because of lack of direct dust measurements in the inner solar system and so one needs to rely on zodiacal light observations that are difficult to interpret. Mercury has an unstable atmosphere, and the source processes of Na in its atmosphere are unclear. Results of past observations have revealed that the atmospheric Na density has no or low correlation with the solar flux, sunspot number, heliocentric distance, or solar radiation pressure. We show that the variability of Mercury's atmospheric Na density depends strongly on the IPD distribution. That is, Na density is low (high) when Mercury is far away from (close to) the symmetry plane of IPD, and so one can infer the IPD distribution near Mercury orbit from the temporal variability of Na density in Mercury's atmosphere.

  16. Trisodium citrate, Na3(C6H5O7)

    PubMed Central

    Rammohan, Alagappa; Kaduk, James A.

    2016-01-01

    The crystal structure of anhydrous tris­odium citrate, Na3(C6H5O7), has been solved and refined using synchrotron X-ray powder diffraction data, and optimized using density functional theory (DFT). There are two independent five-coordinate Na+ and one six-coordinate Na+ cations in the asymmetric unit. The [NaO5] and [NaO6] polyhedra share edges and corners to form a three-dimensional framework. There are channels parallel to the a and b axes in which the remainder of the citrate anions reside. The only hydrogen bonds are an intra­molecular one between the hy­droxy group and one of the terminal carboxyl­ate O atoms and an intermolecular one between a methylene group and the hydroxyl O atom. PMID:27308044

  17. Feasibility study for a secondary Na/S battery

    NASA Technical Reports Server (NTRS)

    Abraham, K. M.; Schiff, R.; Brummer, S. B.

    1979-01-01

    The feasibility of a moderate temperature Na battery was studied. This battery is to operate at a temperature in the range of 100-150 C. Two kinds of cathode were investigated: (1) a soluble S cathode consisting of a solution of Na2Sn in an organic solvent and (2) an insoluble S cathode consisting of a transition metal dichalcogenide in contact with a Na(+)ion conducting electrolyte. Four amide solvents, dimethyl acetamide, diethyl acetamide, N-methyl acetamide and acetamide, were investigated as possible solvents for the soluble S cathode. Results of stability and electrochemical studies using these solvents are presented. The dialkyl substituted amides were found to be superior. Although the alcohol 1,3-cyclohexanediol was found to be stable in the presence of Na2Sn at 130 C, its Na2Sn solutions did not appear to have suitable electrochemical properties.

  18. Na-rich layered Na2Ru0.95Zr0.05O3 cathode material for Na-ion batteries

    NASA Astrophysics Data System (ADS)

    Song, Shufeng; Kotobuki, Masashi; Zheng, Feng; Li, Qibin; Xu, Chaohe; Wang, Yu; Li, Wei Dong Z.; Hu, Ning; Lu, Li

    2017-02-01

    Structures and electrochemical performances of Na-rich layered cathode Na2RuO3 are studied by substitution of Zr for Ru. Na2Ru0.95Zr0.05O3 exhibits a combination of disordered and ordered stacking state with a weight fraction of ∼61.57% and 38.43%, respectively. The disordered and ordered Na2Ru0.95Zr0.05O3 exhibits reversible capacity of 137 mAh g-1 that is consistent with the theoretical capacity at a current density of 1 C. In addition, the material shows good cyclability with a capacity retention of 77% after 200 cycles at current density of 1 C, and the Coulombic efficiency remains at about 99% during cycling. The structural evolutions of the Na-rich layered Na2Ru0.95Zr0.05O3 during de(sodiation) have been investigated and found to proceed via a biphasic mechanism.

  19. Role of Na+,K+-pumps and transmembrane Na+,K+-distribution in muscle function. The FEPS lecture - Bratislava 2007.

    PubMed

    Clausen, T

    2008-03-01

    Na(+),K(+)-ATPase situated in the plasma membrane mediates active extrusion of Na(+) and intracellular accumulation of K(+). This transport system the Na(+),K(+)-pump is the major regulator of the transmembrane distribution of Na(+) and K(+), and is itself subject to regulation by a wide variety of factors in skeletal muscles. The excitation of skeletal muscles is elicited by a rapid influx of Na(+), followed by an equivalent efflux of K(+) across sarcolemmal and t-tubular membranes. Due to their size and sudden onset, these events constitute the major transport challenge for the Na(+),K(+)-pumps. Skeletal muscles contain the largest single pool of K(+) in the organism. During intense exercise, the Na(+),K(+)-pumps cannot readily reaccumulate K(+) into the muscle cells. Therefore, the working muscles undergo a net loss of K(+), causing up to a doubling of the K(+) concentration in the arterial blood plasma in less than 1 min and even larger increases in interstitial K(+). This may induce depolarization, loss of excitability and force, in particular in muscles, where the excitation-induced passive Na(+),K(+)-fluxes are large. During continuous stimulation of isolated rat muscles, there is a highly significant correlation between the rise in extracellular K(+) and the rate of force decline. Fortunately, excitation increases the Na(+),K(+)-pumping rate within seconds. Thus, maximum activation of up to 20-fold above the resting transport rate may be reached in 10 s, with utilization of all available Na(+),K(+)-pumps. In muscles, where excitability is reduced by pre-exposure to high [K(+)]o, acute activation of the Na(+),K(+)-pumps by hormones or intermittent electrical stimulation restores excitability and contractility. In working muscles, the Na(+),K(+)-pumps, due to rapid activation of their large transport capacity, play a dynamic regulatory role in the from second to second ongoing restoration and maintenance of excitability and force. Excitation is a self

  20. Single Na+ channels activated by veratridine and batrachotoxin

    PubMed Central

    1987-01-01

    Voltage-sensitive Na+ channels from rat skeletal muscle plasma membrane vesicles were inserted into planar lipid bilayers in the presence of either of the alkaloid toxins veratridine (VT) or batrachotoxin (BTX). Both of these toxins are known to cause persistent activation of Na+ channels. With BTX as the channel activator, single channels remain open nearly all the time. Channels activated with VT open and close on a time scale of 1-10 s. Increasing the VT concentration enhances the probability of channel opening, primarily by increasing the rate constant of opening. The kinetics and voltage dependence of channel block by 21-sulfo-11-alpha-hydroxysaxitoxin are identical for VT and BTX, as is the ionic selectivity sequence determined by bi-ionic reversal potential (Na+ approximately Li+ greater than K+ greater than Rb+ greater than Cs+). However, there are striking quantitative differences in open channel conduction for channels in the presence of the two activators. Under symmetrical solution conditions, the single channel conductance for Na+ is about twice as high with BTX as with VT. Furthermore, the symmetrical solution single channel conductances show a different selectivity for BTX (Na+ greater than Li+ greater than K+) than for VT (Na+ greater than K+ greater than Li+). Open channel current-voltage curves in symmetrical Na+ and Li+ are roughly linear, while those in symmetrical K+ are inwardly rectifying. Na+ currents are blocked asymmetrically by K+ with both BTX and VT, but the voltage dependence of K+ block is stronger with BTX than with VT. The results show that the alkaloid neurotoxins not only alter the gating process of the Na+ channel, but also affect the structure of the open channel. We further conclude that the rate-determining step for conduction by Na+ does not occur at the channel's "selectivity filter," where poorly permeating ions like K+ are excluded. PMID:2435846